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7785787
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Combined left ventricular wall motion and myocardial perfusion stress imaging in the initial assessment of patients with a recent uncomplicated myocardial infarction.
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The aim of the study was to examine the ability to simultaneously assess left ventricular function and myocardial perfusion by using a single injection of technetium-99m sestamibi at rest and during submaximal exercise to identify high-risk patients with left main, proximal left anterior descending (LAD), or three-vessel coronary artery disease (CAD) after an uncomplicated acute myocardial infarction (AMI). Multiple studies have evaluated the separate value of the exercise ECG, myocardial perfusion scintigraphy, and radionuclide angiocardiography (RNA) for identifying patients with severe CAD. The availability of technetium-99m (Tc99m)-labeled myocardial imaging agents offers the opportunity to evaluate simultaneously ventricular function and myocardial perfusion during a single exercise session. Only limited data are available about the value of this combined technique in the workout of patients early after an uncomplicated AMI. Combined first-pass RNA and myocardial perfusion tomoscintigraphy (SPECT) at rest and during submaximal exercise were performed in 52 patients, less than six weeks after an uncomplicated AMI, with use of Tc99m sestamibi. Patients were classified in two subgroups according to the presence of left main, proximal LAD, or three-vessel CAD. Stepwise logistic regression analysis was used to determine the independent predictors of severe CAD. All patients underwent the exercise testing without any medical complication. On univariate analysis, the global left ventricular ejection fraction (LVEF), wall motion score, and myocardial perfusion score, both at rest and at submaximal exercise, were significantly associated with the presence of severe CAD. The response of LVEF to exercise, and the presence of exercise-induced wall motion or myocardial perfusion abnormalities, were not associated with the severity of CAD. On multivariant analysis only the wall motion score during exercise was an independent predictor for the presence of severe CAD (P < 0.001, r = 0.6). In analyzing patients with anterior AMI separately, LVEF at submaximal exercise was the most accurate predictive parameter. If a cutoff value of 40% was chosen, the LVEF at exercise had a sensitivity of 85% and a specificity of 78% for the detection of severe CAD. In patients with inferior AMI, neither LVEF nor wall motion or myocardial perfusion scores were useful for differentiating the two subgroups. In these patients the presence of an additional perfusion defect during exercise in one of the anterior wall segments yielded a sensitivity of 70% and a specificity of 75% for the presence of severe CAD. simultaneous evaluation of LV function and myocardial perfusion at submaximal exercise, using a single injection of Tc99m-sestamibi, is a safe and accurate technique for selecting patients with severe CAD after an uncomplicated AMI.
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7785786
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Contraction of isolated porcine coronary arteries is inhibited by high concentrations of propranolol.
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Isometric tension responses of isolated porcine coronary artery rings were studied in the presence of concentrations of propranolol higher than those necessary to block effects mediated by beta-adrenergic receptors. Propranolol (50-300 microM) inhibited contractions induced by 30 mM KCl and by histamine, norepinephrine, and acetylcholine in a concentration-dependent, noncompetitive fashion. The (+) propranolol isomer and the racemic mixture were equipotent inhibitors of contraction. Propranolol inhibition was partly reversed by increased extracellular Ca++. These effects of propranolol thus appeared to be independent of beta-blockade and could be relevant to some of the drug's observed but still unexplained in vivo actions.
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7785785
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Isolation of pure populations of epithelial and myoepithelial cells from the normal human mammary gland using immunomagnetic separation with Dynabeads.
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Monoclonal antibodies to epithelial membrane antigen and common acute lymphoblastic leukemia antigen were bound to second antibody-coated magnetic microspheres. These specific antibody/bead complexes were then used to directly isolate purified epithelial and myoepithelial cells from normal breast organoid cell preparations by magnetic separation. Near homogeneous cell populations were selected with yields of 10-20 x 10(6) epithelial and myoepithelial cells per organoid preparation. Repeated purification steps allowed almost complete depletion of myoepithelial cells for RNA studies. Tissue culture of separated cell populations in appropriate defined media further ensured purity of cell type and was unimpeded by Dynabead attachment.
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7785784
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A microtiter plate-based high-throughput DNA purification method.
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A fast, reliable, inexpensive, and high-throughput method to purify DNA has been developed. It is based on DNA amplification by polymerase chain reaction utilizing a mini spin-column made from a 96-well membrane-bottomed assay plate. With this method, 50% of the DNA is recovered routinely using Sephacryl-500HR as filtration media. Purified DNA can then be used in various enzymatic manipulations, such as sequencing and hybridization. This provides an economical alternative protocol for routine large-scale purification of DNA templates for sequencing or other enzymatic manipulations.
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7785783
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A quantitative test for copper using bicinchoninic acid.
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We describe a direct colorimetric assay for copper in serum and biological samples using 2,2'-bicinchoninic acid (BCA), a common reagent in most laboratories. BCA offers the advantage of being highly sensitive and specific for Cu(I) which rapidly forms an intense purple complex in the presence of BCA. The complex has peak absorbances at 562 and 354.5 nm with molar absorptivities of 7.7 x 10(3) liter mol-1 cm-1 and 4.6 x 10(4) liter mol-1 cm-1, respectively. Interference by other metal ions, pH, and detergents is minimal and the results correlate strongly with atomic absorption spectrophotometry.
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7785782
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Simultaneous determination of enzyme activity and enzyme quantity in single human erythrocytes.
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An integrated laser-based fluorescence enzyme assay and particle-counting immunoassay system with zeptomole sensitivity has been developed for simultaneous determinations of activity and concentration of enzymes in single erythrocytes. The product NADPH of the reaction between glucose-6-phosphate and NADP+ catalyzed by glucose-6-phosphate dehydrogenase (G6PDH) is monitored. Simultaneously, the agglutination of antibody-coated particles in the presence of G6PDH produces large particles which are counted by light scattering. The correlation between the two parameters indicates that on average only about 35% of the enzyme in individual cells is active. There is more than a 10-fold cell-to-cell variation in the ratios of the two parameters. This indicates that there are multiple mechanisms for the degradation of intracellular enzymes as a function of cell age.
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7785780
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Imaging and quantitation of chemiluminescence using photoexcitable storage phosphor screen.
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A novel storage phosphor (SrS:Ce,Sm) imaging screen optimized for the detection of luminescence has been developed. When coupled with an appropriate scanning system, this screen exhibits the following characteristics: (i) a range of visible light detection between 400 and 500 nm with a peak response at 450 nm; (ii) sensitivity comparable to X-ray film; (iii) 200-microns resolution; (iv) linear dynamic range greater than four orders of magnitude; and (v) a uniformity of response of +/- 1.32% coefficient of variation. These features facilitate the detection and accurate quantitation of light radiation produced from the enzymatic catalysis of chemiluminescent substrates such as 1,2-dioxetanes and luminol. Its suitability for chemiluminescent applications is demonstrated by the analysis of cosmid hybridization and enzyme-linked immunosorbent assay samples.
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7785781
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A continuous spectrophotometric assay for protein phosphatases.
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A continuous spectrophotometric assay for the determination of protein phosphatase activity is presented. The assay incorporates the coupled enzyme system of Webb (M. R. Webb, 1992, Proc. Natl. Acad. Sci. USA 89, 4884-4887), which used purine nucleoside phosphorylase and the chromophoric substrate 7-methyl-6-thioguanosine for the quantitation of inorganic phosphate. The assay is exemplified and validated here for the phosphorylase phosphatase activity of protamine-stimulated protein phosphatase 2A1 (PP-2A1). The effects of reaction components on the activities of both PP-2A1 and purine nucleoside phosphorylase were studied. The application of the coupled assay system to kinetic analysis of the phosphorylase phosphatase activity of PP-2A1 and to the assay of the catalytic subunits of type 1 and 2A protein phosphatases and a recombinant type 1 catalytic subunit is demonstrated. The applicability of this coupled enzyme system to the assay of other protein phosphatases is discussed.
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7785779
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Correlation of electrophoretic mobilities of proteins and peptides with their physicochemical properties.
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Electrophoretic mobilities, mu, of nine proteins (M(r) 14,200 to 70,000) in 28 mM Tris/47 mM glycine buffer at pH 8.77 and 5 mM ionic strength were measured by laser Doppler velocimetry and correlated to ratios of charge (q) to molecular weight (M(r)) and shape factor (f/f0) by the equation mu(f/f0) = (Aq/Mpr-B). This correlation was previously reported for peptides and proteins for mu measured at 100 mM ionic strength. When A = 6.048 x 10(-3), B = 1.13 x 10(-5), and p = 2/3, the correlation fitted 51 measured and literature values over the molecular weight range of 178 to 140,000 for components whose electrophoretic mobilities ranged from +13.35 x 10(-5) to -19.7 x 10(-5) cm2/(V.s). The experimental measurements confirm the general suitability of p = 2/3 and show that the familiar charge/mass relation for electrophoresis is applicable to proteins in low-ionic-strength buffers which are typical of electrochromatography systems. Extrapolation of the correlation to different ionic strengths indicates that a low-ionic-strength buffer amplifies differences of electrophoretic mobility as a function of charge/mass, while high ionic strength diminishes such differences.
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7785778
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A double labeling procedure for lipoproteins: independent visualization of dual ligand-receptor interaction with colloidal gold- and 125I-labeled ligands.
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The analysis of multiple ligand binding to a single receptor molecule poses a methodological challenge. The chicken oocyte 95-kDa receptor for the uptake of the two major yolk lipoprotein precursors very low-density lipoprotein (VLDL) and vitellogenin (VTG) is such a multipotent transport receptor. Here we describe methods for rapid independent and simultaneous analysis of VLDL and VTG binding to this receptor, termed VLDL/VTG receptor. First, further development of a one-step labeling protocol for chicken lipoproteins with colloidal gold (Au) to visualize independently the binding of VLDL and VTG to the chicken VLDL/VTG receptor is reported. The advantage of this protocol is that the preparation of the Au-lipoprotein conjugates is rapid, and utilization of Au-lipoprotein complexes in ligand blots does not require their further purification, while signal enhancement by silver staining is still applicable. Second, the simultaneous use of 125I- and Au-labeled ligands in a one-step ligand blotting procedure facilitates the direct demonstration of the competitive interaction of VLDL and VTG with the receptor. Following sequential processing of the nitrocellulose strips, binding of differently labeled ligands can be studied independently. In summary, we describe a procedure for differential labeling of lipoproteins and its application toward the analysis of receptors that bind more than one ligand.
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7785777
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Precipitation of Hevea brasiliensis latex proteins with trichloroacetic acid and phosphotungstic acid in preparation for the Lowry protein assay.
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Many proteins derived from the latex of Hevea brasiliensis that remain soluble in trichloroacetic acid (TCA) can be precipitated by phosphotungstic acid (PTA). A combination of 5% TCA and 0.2% PTA precipitates a wide range of proteins effectively even when they are present in low concentrations (below 1 microgram ml-1). In addition to its protein purification function, acid precipitation also increases the sensitivity of the subsequent protein assay by allowing the test sample to be concentrated. Another advantage of protein precipitation by TCA and PTA is that very small amounts of protein (of the order of 10 micrograms) can be repeatably recovered without the use of precipitate-bulking agents such as sodium deoxycholate. This general procedure of protein purification and concentration is simple and rapid, but the use of PTA may not be fully compatible with the Bradford protein assay. A modified Lowry microassay is described which enables about 3 micrograms ml-1 to be quantitated at the photometric absorbance of 0.05. When used in conjunction with protein concentration by precipitating with TCA/PTA, approximately 0.4 microgram ml-1 protein present in 6 ml of solution can be assayed.
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7785775
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A comparison of methods for determining total body protein.
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The aim of the study was to find the optimal method (with respect to convenience and accuracy) for determining total protein in whole-body homogenates of rats. Three different protein extraction methods and five different protein concentration methods were assessed. The results were compared against a reference value measured by complete amino acid analysis after acid hydrolysis. The data demonstrated that extraction with 5% (w/v) sodium dodecylsulfate (SDS) in 0.5 N NaOH was far superior to that with water alone or to 6 N guanidine-HCl. A comparison of the Biuret, Bradford, and bicinchoninic acid methods on the SDS-NaOH-extracted samples showed that the Biuret method was optimal, giving a value that was 90% of the reference value with a small variation (2.4% of the mean). The Kjeldahl method gave the correct protein concentration only when a nitrogen factor of 5.51 +/- 0.03 (N = 5) was applied. The results suggest that extraction with SDS-NaOH followed by the Biuret procedure is a good method for measuring protein concentrations in whole body rat homogenates.
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7785776
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Reduction of strong lipase-polyclonal antibodies binding by limited proteolysis.
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Initial attempts to purify Geotrichum candidum lipase (EC 3.1.1.3) using immunoaffinity chromatography have been hampered by the tight binding of the lipase to the immobilized rabbit anti-GCL IgG. Stringent elution conditions were unable to release more than a few percent of the antigen. To decrease the tight binding, the immunosorbent was treated with minute amounts of different proteases, of which elastase proved to be most effective. Using the elastase-treated immunosorbent both natural and recombinant GCL II were purified to homogeneity with 30% of lipase recovered from the immunoaffinity chromatography step.
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7785768
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A bisulfite method of 5-methylcytosine mapping that minimizes template degradation.
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The bisulfite method is a highly sensitive approach to 5-methylcytosine mapping that utilizes the capability of the polymerase chain reaction to exponentially amplify DNA. We have observed that the bisulfite reaction results in a significant level of template degradation due to DNA depurination. Furthermore, our data suggest that the DNA fragmentation which occurs limits the sensitivity of the method. We describe a simple solution to limit degradation of the DNA template.
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7785769
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Correlation between the light scattering and the mitochondrial content of normal tissues and transplantable rodent tumors.
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The development of noninvasive optical studies necessitates an understanding of the biological parameters which affect light propagation in soft tissues. In the present report, we have measured the optical properties of various normal (i.e., perfused liver, brain, skeletal muscle, white adipose tissue) and neoplastic rodent tissues (i.e., glioma, hepatoma, mammary adenocarcinoma) by using time-resolved spectroscopy. The contribution of the hemoglobin (+ myoglobin in the case of muscle) to the total light absorption at 780 nm has been determined. This contribution varies from about 25% (brain, skeletal muscle) to about 100% (white adipose tissue, 13762A mammary adenocarcinoma, 9L glioma). These results are explained by different blood volume fractions in the tissues and by the existence at 780 nm of other chromophores, such as the mitochondrial cytochrome oxidase. Secondly, the dependence of the light scattering of the tissue on both the cell and the mitochondrial content has been analyzed. The results indicate that there is no correlation between the light scattering and the DNA content, measured as an indicator of the cell number in the tissue. The scattering coefficient is proportional to both the succinate dehydrogenase activity and the mitochondrial protein content of the tissue, which are indicators of the mitochondria content of the tissue when based upon estimates of tissue wet weight.
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7785766
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Simplified high-sensitivity sequencing of a major histocompatibility complex class I-associated immunoreactive peptide using matrix-assisted laser desorption/ionization mass spectrometry.
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Cytotoxic T cells (CTL) are known to recognize small peptide fragments of cytoplasmic proteins bound to major histocompatibility complex (MHC) class I molecules on cell surfaces. Recent work indicates that tumor antigens are processed and presented in a manner similar to viral antigens. Identification of the peptides recognized by tumor-specific CTL would provide valuable information about their parent proteins, as well as allowing for the development of recombinant antigen-specific tumor vaccines. While highly represented MHC-bound peptides have been routinely purified by reversed-phase HPLC for Edman degradation sequencing, identification and sequencing of infrequent peptides that represent the biologically relevant targets of tumor-specific CTL have proved elusive. We have combined matrix-assisted laser desorption/ionization mass spectrometry with on-slide exopeptidase digestion to successfully identify and directly sequence a model tumor-specific peptide antigen derived from an integrated viral gene. The enhanced sensitivity of this technique (femtomolar range) allows for the sequencing of specific MHC-bound peptides derived from as few as 1 x 10(9) cells.
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7785767
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An assay for galactosyltransferase-I activity in articular cartilage.
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UDP-D-Galactose:D-xylose galactosyltransferase (Galactosyltransferase-I) is an enzyme involved in the synthesis of the linkage region of chondroitin sulfate. Measurement of galactosyltransferase-I in mature articular cartilage has depended on milling such tissue in liquid nitrogen to break open the cells and enable interaction of exogenous substrates with galactosyltransferase-I. This process requires large amounts (approximately 1 g wet wt) of cartilage. This paper reports the development of an assay for galactosyltransferase-I in articular cartilage where 10-25 mg (wet wt) of the tissue was extracted with a buffer containing the detergent Thesit. This assay was more time efficient, required less tissue, and was linear for up to 6 h. It was effective on both mature bovine articular cartilage and embryonic chick epiphyseal cartilage, detecting 100 and 68% of total galactosyltransferase-I activity, respectively. The higher number of measurements available allowed kinetic studies to be conducted on bovine articular cartilage explant cultures under conditions of up- and down-regulation. Incubation with fetal calf serum resulted in an increase in galactosyltransferase-I activity. Galactosyltransferase-I activity, however, did not change markedly in cartilage cultured in the absence of fetal calf serum or in the presence of cycloheximide. A soluble preparation of galactosyltransferase-I, extracted from bovine articular cartilage using Thesit, eluted from a Superose-6 column, with a molecular mass of about 55 kDa.
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7785765
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Fluorescence-based enzymatic assay by capillary electrophoresis laser-induced fluorescence detection for the determination of a few beta-galactosidase molecules.
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beta-Galactosidase can be assayed by monitoring the generation of the fluorescent products, fluorescein-mono-beta-D-galactopyranoside and fluorescein, when the fluorogenic substrate fluorescein-di-beta-D-galactopyranoside is used. We have used capillary electrophoresis with ultrasensitive laser-induced fluorescence detection to monitor the formation of the fluorescent products of off-column enzymatic reactions. By analyzing as little as 40 pl of the enzymatic mixture we obtain limits of detection of 6.5 x 10(-14) M beta-galactosidase or 1.6 molecules based on the detection of fluorescein-mono-beta-D-galactopyranoside.
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7785764
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Identification of neutral and sialyl N-linked oligosaccharide structures from human serum glycoproteins using three kinds of high-performance liquid chromatography.
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The distribution of neutral and sialyl N-linked oligosaccharides from human serum glycoproteins has been studied using three kinds of HPLC columns as described below. N-linked oligosaccharides were released from chymotrypsin- and trypsin-digested glycopeptides of human serum by means of glycoamidase (from almond) digestion. The reducing ends of the oligosaccharides were derivatized with the fluorescent reagent 2-aminopyridine (PA). The mixture of PA-oligosaccharides was separated by high-performance liquid chromatography on a diethylaminoethyl column according to the sialic acid content. Each fraction separated was then applied on an octadecylsilyl (ODS) column, and the elution volume of each peak was recorded as a glucose unit on the X-axis. Then, each of the separated oligosaccharides was applied to the amide column. Each peak's elution volume was recorded as a glucose unit on the Y-axis. The elution volumes from these two columns (ODS and amide) provide a unique set of coordinates. The structure of each sialyl oligosaccharide fraction was analyzed by the same two-dimensional sugar-mapping technique as previously developed for neutral oligosaccharides. This was combined with exoglycosidase digestion and high-resolution proton NMR measurement. Fourteen neutral, eight mon-sialyl, four di-sialyl, and five tri-sialyl oligosaccharides were isolated from human serum and their structures were characterized.
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7785763
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Preparation and characterization of RNA standards for use in quantitative branched DNA hybridization assays.
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RNA standards were developed for use in quantitative hybridization assays such as the Quantiplex HCV RNA Assay and Quantiplex HIV RNA Assay, which are based on branched DNA signal amplification. In vitro transcripts ranging in size from 0.5 to 9.4 kb were prepared and purified by phenol extraction following gel electrophoresis or column chromatography. Aliquots of the transcripts were digested to nucleosides and phosphate and then quantified by phosphate analysis against the U.S. National Institute of Standards and Technology phosphate standard. The quantitation was checked by OD260 and by either hyperchromicity or isotopic tracer analysis. The quantitation of each lot of RNA agreed within 20% by the three methods. The reproducibility of the methods was tested by preparing a total of 13 lots of standard RNAs. The average percentage full-length RNA of the 13 lots was 82%, with a range of 59 to 97%. The standard RNAs were used to test the ability of the branched DNA hybridization assay to quantify all target RNAs accurately regardless of size or slight variations in sequence. Standard Hepatitis C virus (HCV) RNAs of 1.3, 2.2, and 3.2 kb showed that size has no detectable effect on quantitation in the branched DNA hybridization assay. Three different lots of standard 3.2-kb HCV RNA were serially diluted and quantified over a thousand-fold range in the branched DNA hybridization assay. The average signal per attomole of target varied by less than 20% among the 3 lots. Standard HCV RNA transcripts were also prepared from clones of HCV subtypes 1b and 3a to study the effects of target sequence diversity and probe design on quantitation by hybridization.(ABSTRACT TRUNCATED AT 250 WORDS)
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7785762
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A complete platelet system for metabolic studies: pure, defined, and viable over 8 hours.
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We have been using a human platelet preparation to investigate various aspects of cellular metabolism. These experiments require a pure, quantitated platelet preparation that is viable for up to 8 h. The purity of the preparation has previously been characterized and we have now assessed its viability over 8 h and developed a simple spectrophotometric counting method. This method of counting results in estimations that are within 6% of those from an electronic cell counter (Coulter). Pure platelets stored in a Hepes physiological saline were resuspended periodically in autologous plasma to assess function over 24 h. The platelets consumed oxygen, changed shape, aggregated, and released dense granule ATP at all times. There was a slow and linear decrease in the various processes with time, ranging from 1.7% per hour for oxygen consumption to 3.8% per hour for percentage aggregation. The preparation is therefore not stable, but the changes with time are small and defined and it represents a useful system for the study of platelet and cell biology.
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7785761
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Isotopomer study of lipogenesis in human hepatoma cells in culture: contribution of carbon and hydrogen atoms from glucose.
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Recent developments in the application of stable isotopes and mass spectrometry have permitted the estimation of precursor enrichment and fractional synthesis of the product through mass isotopomer analysis. Thus, the application of isotopomer analysis in studies with 2H- and 13C-labeled glucose may potentially overcome the limitations of traditional methods which can only estimate the fractional use of carbon and hydrogen from glucose for lipogenesis. To illustrate this approach, isotope incorporation and mass isotopomer distribution were determined in fatty acids and cholesterol from a hepatoma cell line (Hep G2) grown in media containing specific (C1 or C6) 2H- or 13C-labeled glucose. Using the binomial model, the respective precursor enrichment, and fractional synthesis of palmitate, stearate and cholesterol were determined using mass isotopomer distribution analysis. In 1 week, 80% of palmitate, 65.5% of stearate, and 50% of cholesterol molecules in the cell extract were derived from de novo synthesis. Under serum-free condition, glucose contributed about 80% of the carbon of the newly synthesized lipids. Using the relative isotope yield of [1-13C] and [6-13C]glucose and a standard formula, the contribution of the pentose pathway to glucose catabolism was calculated to be 4.7%. Fractional syntheses of palmitate, stearate, and cholesterol determined using [1-2H]glucose agreed well with values determined using 13C-labeled glucose. After correcting for the contribution of deuterium label from the glycolytic pathway, the deuterium from [1-2H]glucose contributed 4.7% of the total reducing equivalents for lipogenesis. Unlike radioisotope studies, the stable isotope approach provides information from the perspective of the product and insight into the economy of acetyl units and reducing equivalents which were otherwise not available.
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7785760
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Development and application of a fluorometric assay for mammalian membrane dipeptidase.
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Membrane dipeptidase (EC 3.4.13.19) is a widely distributed mammalian cell surface enzyme involved in the metabolism of glutathione, leukotriene D4, and certain beta-lactam antibiotics. In this study we have developed a sensitive and rapid assay for membrane dipeptidase based on the fluorometric detection of the D-Phe released from the model substrate Gly-D-Phe. The released D-Phe is first acted on by D-amino acid oxidase in the presence of flavin adenine dinucleotide. The resulting hydrogen peroxide is then metabolized by peroxidase in the presence of the acceptor substrate p-hydroxyphenylacetic acid which is converted to a highly fluorescent compound. The assay configuration is sensitive down to 0.1 nmol D-Phe and can accurately measure membrane dipeptidase activity even in the presence of large amounts of contaminating protein. The membrane dipeptidase assay and the subsequent fluorometric detection of the released D-Phe can be performed in microtiter plates, thus taking less than 1 h to process 96 samples. This sensitive and rapid assay will be useful for the routine measurement of membrane dipeptidase activity in a number of different applications.
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7785759
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[Controlled hypotension].
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Induced hypotension is defined as a reduction in mean arterial blood pressure to 50-60 mm Hg in normotensive subjects. The aim of induced hypotension is to decrease intraoperative blood loss, decrease the need for blood transfusions and improve operating conditions. Most studies indicate that induced hypotension can decrease intraoperative blood loss by 50% in many surgical procedures; however, some studies report that blood loss is not significantly reduced. Current methods of induced hypotension are based on the use of rapid and short-acting vasodilators as primary agents (nitroprusside, nitroglycerine, urapidil), supplemented by volatile anesthetics (isoflurane) and/or beta-blockers (esmolol) to improve effect, reduce dosage and prevent side effects (reflex tachycardia, tachyphylaxis, rebound hypertension). Proper positioning of the patient and controlled ventilation aid in reducing blood loss. Major risks of induced hypotension are a reduction in blood flow (i.e. ischaemia) of vital organs (brain, myocardium) and elevation of intracranial pressure in neurosurgical patients. Thus, major contraindications of induced hypotension are severe coronary artery disease, hypertension combined with arteriosclerosis of cerebral vessels and increased intracranial pressure in patients with cerebral disease. Complications are rare in otherwise healthy patients, but may be higher in elderly patients and those with underlying organ dysfunction. Therefore, careful assessment and selection of patients, together with consideration of the potential complications, appropriate choice of drugs and invasive beat-by-beat monitoring, are essential for the safe practice of induced hypotension.
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7785758
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[Intravenous administration of ondansetron vs. metoclopramide for the prophylaxis of postoperative nausea and vomiting].
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This randomized, double-blind, multicentre, parallel-group study compared the efficacy and safety of an intravenous dose of ondansetron 4 mg for the prevention of postoperative nausea and vomiting (PONV) with metoclopramide 10 mg and placebo in patients undergoing major gynaecological surgery. A total of 1044 patients (465 ondansetron, 462 metoclopramide, 117 placebo) received study medication immediately prior to induction of anaesthesia and were included in the analysis of data. The proportion of patients experiencing no emesis and no nausea or provided with rescue antiemetic medication, the number of emetic episodes, and the duration and severity of nausea were recorded during the 24-h period after recovery. Significantly more patients who received ondansetron had no emetic episodes (44%) than those who received metoclopramide (36%, P = 0.049) or placebo (25%, P < 0.001). A higher proportion of patients receiving ondansetron (32%) did not experience nausea (metoclopramide 24%, P = 0.009; placebo 16%, P < 0.001). Significantly fewer patients in the ondansetron group required rescue medication or were withdrawn due to treatment failure (P < 0.05). In the ondansetron group the total number of emetic episodes, the median time to the first emetic episode or treatment failure, and the duration and severity of nausea were reduced significantly compared with metoclopramide or placebo (P < 0.05). The safety profile was similar for each treatment group.
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7785756
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[Heat and moisture exchangers for conditioning of inspired air of intubated patients in intensive care. The humidification properties of passive air exchangers under clinical conditions].
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Heat and moisture exchangers (HME) are used as artificial noses for intubated patients to prevent tracheo-bronchial or pulmonary damage resulting from dry and cold inspired gases. HME are mounted directly on the tracheal tube, where they collect a large fraction of the heat and moisture of the expired air, adding this to the subsequent inspired breath. The effective performance depends on the water-retention capacity of the HME: the amount of water added to the inspired gas cannot exceed the stored water uptake of the previous breath. This study evaluates the efficiency of four different HME under laboratory and clinical conditions using a new moisture-measuring device. METHODS. In a first step, the absolute efficiency of four different HME (DAR Hygrobac, Gibeck Humid-Vent 2P, Pall BB 22-15 T, and Pall BB 100) was evaluated using a lung model simulating physiological heat and humidity conditions of the upper airways. The model was ventilated with tidal volumes of 500, 1,000, and 1,500 ml and different flow rates. The water content of the ventilated air was determined between tracheal tube and HME using a new high-resolution humidity meter and compared with the absolute water loss of the exhaled air at the gas outlet of a Siemens Servo C ventilator measured with a dew-point hygrometer. Secondly, the moisturizing efficiency was evaluated under clinical conditions in an intensive care unit with 25 intubated patients. Maintaining the ventilatory conditions for each patient, the HME were randomly changed. The humidity data were determined as described above and compared with the laboratory findings. RESULTS AND DISCUSSION. The water content at the respirator outlet is inversely equivalent to the humidity of the inspired gases and represents the water loss from the respiratory tract if the patient is ventilated with dry gases. Moisture retention and heating capacity decreased with higher volumes and higher flow rates. These data are simple to obtain without affecting the patient and can easily be interpreted. It was demonstrated that, compared to physiological conditions, the DAR Hygrobac and Gibeck Humid Vent 2P-HME coated with hygroscopic salts-were able to maintain sufficient inspiratory humidity and heat. The Pall-HME, solely a condensation humidifier, did not meet the physiological requirements.
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7785757
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[Three isoflurane preparations from various manufacturers. A comparison of isoflurane concentrations in fresh gas after vaporization with a Drager vaporizer type 19.3].
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The purpose of this study was to check the precision of the Dräger vaporizer model 19.3 when filled with three different preparations of isoflurane. Six Dräger vaporizers model 19.3 calibrated with forene were filled with forene (Abbott), isoflurane (Lilly) and isoflurane (Pharmacia); gas output was measured by infrared absorption (Irina, Dräger) at vaporizer settings of 0.2, 0.4, 0.6, 0.8, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0 and 5.0 vol%, starting with a fresh gas flow of 2 1/min followed by 4, 6 and 12 1/min. Thus each of the three isoflurane preparations was checked in six different vaporizers and with four different fresh gas flows. Within the concentration range used in clinical practice there was no significant difference in the delivery of the three isoflurane preparations. Each of the six vaporizers produced a controllable and predictable concentration of the three preparations. Vaporizers of Dräger type 19.n calibrated with forene deliver the same predictable concentration of the volatile anaesthetic when filled with isoflurane from Lilly or isoflurane from Pharmacia instead of forene and may be used without impairment in patient safety. In addition, no specific calibration with one of the new isoflurane preparations is required.
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7785755
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[Postoperative pulmonary function after lung surgery. Total intravenous anesthesia with propofol in comparison to balanced anesthesia with isoflurane].
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After lung resection, early extubation and the rapid return of the patients ability to cooperate is the predominant goal. Propofol anaesthesia is characterised by rapid awakening and recovery of cognitive and psychomotor functions and is consequently desirable for such operations. Experience so far in lung surgery, however, is limited. Besides the level of consciousness we investigated various spirometric parameters after lung resection. Total intravenous anaesthesia was performed with propofol, while balanced anaesthesia was performed with isoflurane. METHODS. A total of 93 patients evaluated electively for wedge excision or lobectomy were enrolled in an open, prospective, randomised, interindividual comparative study. Sixty-three patients could be evaluated with complete data sets. In the evening and the morning before the operation the patients were premedicated orally with clorazepate 0.5-0.7 mg/kg. Anaesthesia was induced in group 1 with propofol (1.0-2.5 mg/kg) and maintained with propofol (4-12 mg/kg) in 50% O2/air. The patients in group 2 received methohexital (1-2 mg/kg) for induction and isoflurane (0.4-2.0 vol%) in 50% O2/air for the maintenance of general anaesthesia. In both groups analgesia was achieved by using fentanyl (up to 10 micrograms/kg) and muscle relaxation by using atracurium. Psychomotor tests (minimal mental state, reaction time) were performed the day before the operation (t1), immediately prior to induction of anaesthesia (t2) and 5 min, 30 min, 60 min, 90 min, 24 h, and 7 days after extubation (t3-t8). Spirometry (forced expiratory volume in 1 s, FEV1; forced vital capacity, FVC; peak expiratory flow, PEF) was carried out at times t1, t2 and t5-t8. RESULTS. The two groups were comparable regarding preoperative status (age, sex, preoperative risk score, psychomotor tests, and spirometric values) and the operation performed (wedge excision/lobectomy, duration of anaesthesia). The extubation time was slightly shorter in the propofol group (18 +/- 8 min) than in the isoflurane group (20 +/- 6 min). Also, the results of the psychomotor tests were somewhat better in the propofol group than those in the isoflurane group. The clearest differences were found in the early postoperative period, but not all differences were significant. Statistically highly significant differences between the two groups were found for the three spirometric parameters. Based on the FEV1 value of the 7th postoperative day, FEV1 taken 60 min after extubation declined by 27.9% in the propofol group vs. 51.7% in the isoflurane group (P = 0.01). At 90 min after extubation the corresponding decline in the propofol group was 26.6%, in the isoflurane group 51.1% (P = 0.003). In addition, the decline of FVC and PEF measured 60 min and 90 min after extubation was significantly smaller in the propofol group than in the isoflurane group. CONCLUSION. The postoperative impairment of lung function after lung resection under propofol anaesthesia is statistically significantly smaller than under isoflurane anaesthesia. Total intravenous anaesthesia with propofol is particularly suitable for this kind of operation.
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7785754
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[Operations with a heart-lung machine in adult members of Jehovah's Witnesses].
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Members of Jehovah's Witnesses refuse blood transfusions and blood products under any circumstances. Because of an improvement in blood salvage techniques in our centre, they are not excluded from open-heart surgery. In recent years recombinant human erythropoietin (rhEPO) has been applied to correct perioperative anemia in these patients. METHODS. Seventeen members of Jehovah's Witnesses who were more than 18 years of age were operated on using various blood salvage technique, e.g., haemoseparation and a high dose of Aprotinin. We present the first three patients treated with 4 x 500 U of i.v. rhEPO/kg body wt. given within 11 days preoperatively. Thirteen of the patients operated on had elevated preoperative risk factors, for instance poor left ventricle, severe aortic valve stenosis, metabolic syndrome, age older than 70 years, etc. In other centres that perform cardiac operations on members of Jehovah's Witnesses, these risk factors represent contraindications for open-heart surgery in these patients. RESULTS. Patients with rhEPO treatment showed a preoperative hematocrit increase of 7 Vol.% within 10 days and no postoperative complications. At the 6th postoperative hour the hematocrit returned to the starting values; in patients without rhEPO, however, the hematocrit generally had not increased to preoperative values even by the 8th day after operation. In 9 patients with preoperative elevated risk factors and a postoperative relative decrease in hematocrit below 33% we observed an uncomplicated postoperative period. Four patients with these risk factors, a pronounced decrease in hematocrit and blood loss postoperatively had various severe complications. CONCLUSIONS. Preoperative treatment with a high dose of rhEPO to enhance the hematocrit and maturity by precursor red blood cells in patients with a hematocrit below 45 Vol.% is a possibility to compensate for the blood loss perioperatively and to avoid complications from a decrease in oxygen transport capacity. The anaemia and high blood loss postoperatively are the main causes for a slightly elevated operation risk in members of Jehovah's Witnesses in all heart centres that perform cardiac operations on these patients. Nevertheless, Jehovah's Witnesses should be not excluded from cardiac operations, since open-heart surgery without use of homologous blood is becoming a routine procedure.
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7785753
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[Anesthesia for heart transplantation in newborn and suckling infants. Special aspects of the hypoplastic left heart syndrome].
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Paediatric cardiac transplantation (pHTX) has gained widespread acceptance as a therapy in end-stage myocardial failure and some forms of congenital heart disease, particularly hypoplastic left heart syndrome (HLHS). The major problems to the anaesthesiologist in these patients are induction of anaesthesia in infants with HLHS and treatment of pulmonary hypertension in the early post-bypass period. PATIENTS AND METHODS. Anaesthesia for pHTX was performed in 15 children < 1 year of age (4-237 days); 12 suffered from HLHS, 2 from endocardial fibroelastosis, and 1 from dilatative cardiomyopathy. Induction of anaesthesia in patients with HLHS IS a challenge to the anaesthesiologist, as he has to maintain the delicate balance between pulmonary and systemic blood flow. Anaesthesia was induced with fentanyl (10-15 micrograms/kg) and pancuronium (0.2-0.4 mg/kg) and maintained with fentanyl (total dosage 70-100 micrograms/kg). Modification of ventilatory parameters such as FiO2, PaCO2, and airway pressure (PEEP, I:E ratio) was used to influence systemic and pulmonary blood distribution in the pre-bypass period according to changes in haemodynamics (target: O2 saturation approximately 75%-80%, PaCO2 45-50 mmHg). Treatment of pulmonary hypertension in the weaning and early post-bypass period consisted of respiratory (PaCO2 < 30 mmHg) and metabolic alkalinisation (pH 7.45-7.55, BE > +3 mmol/l), the use of prostaglandin E1 (3-6-12 micrograms/kg.h), and the phosphodiesterase inhibitor enoximone (10-15 micrograms/kg.min). Additional positive inotropic support was achieved with dobutamine (5-10 micrograms/kg.min), adrenaline (0.1-0.5 micrograms/kg.min), and/or orciprenaline (0.1-0.2 micrograms/kg.min) and calcium chloride (25-100 mg/kg). RESULTS. Two children died intraoperatively and 1 on the 1st postoperative day from overwhelming pulmonary vascular resistance and right ventricular failure. Three children died between 3 and 4 weeks postoperatively, 1 from cytomegalovirus infection, 1 from sepsis, and 1 from acute rejection. Nine patients survived and are well up to 5.5 years after transplantation. CONCLUSION. Pulmonary hypertension in the weaning and early post-bypass period is the main anaesthesiological problem of pHTX, particularly in children with HLHS. A polypragmatic approach to this problem consisting of alkalinisation, pulmonary vasodilatation, and inotropic support is presented and seems to be effective. Further improvements in concepts of pHTX are limited by the lack of donor organs. Though the experience with pHTX in neonates and infants is growing slowly, it might be a routine procedure from the anaesthesiological point of view within a few years in some selected centres.
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7785752
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[Quality control in anesthesiology. Results of a prospective study following the recommendations of the German Society of Anesthesiology and Intensive Care].
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The German Social Law has required quality assurance (QA) procedures since 1989. The measures must be suitable to allow "comparing investigations". In 1992 the German Society of Anaesthesiology and Intensive Care Medicine published recommendations for QA in anaesthesia: most problems during an anaesthetic should be documented in a standardised manner, and thus, a list of 63 pitfalls, events, and complications (PECs) and five degrees of severity were defined. The goal of this study was to determine the frequency of PECs in anaesthesia and to correlate PECs with procedures and preoperative health status. MATERIALS AND METHODS. Demographic data, preoperative findings, type and duration of anaesthesia and operation, and kind and severity of PECs were integrated in an automatically readable anaesthetic data record (ARADR). During 12 months all anaesthetics in our department were documented by the ARADR; the records were read by a reading device and the data stored in a modern SQL database (Informix). Degrees of severity: I. PEC leads to reaction of anaesthetist, no impact for recovery room (RR); II. impact for RR, no impact on transfer to ward; III. significant prolongation of RR stay or additional monitoring on ward; IV. PEC leads to intensive care unit admission; V. disabling damage or death. RESULTS. In all, 18350 anaesthetics were recorded (9055 male, 9295 female); the median age was 41 years (1 day-99 years). In 4251 (23.2%) anaesthetics 5927 PECs occurred, 3412 of them involving the cardiovascular and 949 the respiratory system, the latter with a tendency to higher degrees of severity. PECs caused by technical equipment (126) or lesions caused by anaesthesists (342) had no fatal outcomes and were less severe. Patients in ASA class I had 12.3% anaesthetics with PECs, ASA II 23.3%, ASA III 33.8%, ASA IV 34.9%, and ASA V 58.5%. PECs of degrees IV and V showed a higher incidence in the higher ASA classes. There was no fatal PEC in an ASA class I patient and only one (of 13615) in an elective procedure. Emergency cases had more frequent and more severe PECs: 16 of 19 PECs of degree V were in ASA class IV and V patients and 15 in emergency situations, all of them in surgical patients. Patients with cardiovascular disease had a more frequent incidence of PECs by a factor of 1.39 to 5.93 than those without such disease. CONCLUSIONS. Standardised incident reporting by defined PECs seems a good way to describe problems in anaesthesia. The types of PECs in our study had a similar distribution to those in other investigations, but there was a tendency to less frequent fatal PECs in ASA classes I to IV and more frequent ones in ASA class V. We expect better comparability when multicenter studies are done using identical methods in the next few years. Perhaps different patients collectives with special risks will be detected; efforts in quality improvement could focus on these patients.
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7785751
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[The role of autologous blood transfusion in the the Federal Republic of Germany. Results of a 1993 questionnaire. 1. The reunited Germany].
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The objective of the study was to evaluate the role of autologous blood transfusion in current clinical practice in the Federal Republic of Germany after reunification. Questionnaires were sent to the anaesthesia departments of 684 German hospitals in January 1993. The sample consisted of 400 randomly selected hospitals from the former West Germany ("old federal states") and 284 hospitals from the former German Democratic Republic ("new federal states"). Only hospitals with more than 25 surgical beds were included in the study. The questionnaire contained 36 questions related to (1) general information on the hospital, (2) preoperative autologous blood donation (PABD), (3) preoperative plasmapheresis, (4) isovolaemic haemodilution, (5) perioperative blood salvage, and (6) general management of blood transfusion. A total of 502 completed questionnaires (73%) were returned, 305 from hospitals in the "old federal states" and 197 from hospitals in the former German Democratic Republic. Nine per cent of the responding hospitals were running their own transfusion services, and 56% were located in the vicinity of a regional blood bank. The overall proportion of surgical procedures requiring perioperative blood transfusion ranged from 1% to 90% (median 10%). PABD was performed "not at all" in 18%, "rarely" in 20% "occasionally" in 27%, "frequently" in 17%, and "mostly" in 16% of the responding hospitals. The principal use of PABD was in orthopaedic surgery and cardiac surgery (83% and 70% of the departments in question, respectively). In more than 50% of the hospitals reporting, the PABD service was run by the anaesthesia department. Patients not meeting the established criteria for homologous blood donors were accepted for autologous blood donation "frequently" and "mostly" in 20% and 12% of the hospitals, respectively, but at most "occasionally" in 63% of the hospitals. Preoperative plasmapheresis was performed in 12% of the responding hospitals. Autologous fresh frozen plasma predominantly was used for volume replacement, and for prevention of coagulation disorders when major blood loss was anticipated. Isovolaemic haemodilution was performed "not at all" in 28%, "rarely" in 19%, "occasionally" in 28%, "frequently" in 16%, and "mostly" in 8% of the responding hospitals. The reasons most frequently invoked for not performing haemodilution were "too time consuming" and "too little blood-saving effect". Cell separators for perioperative blood salvage were available in 30% of the responding hospitals. Of the other hospitals not equipped with cell-washing devices, 11% performed perioperative blood salvage of unprocessed blood by means of simple collection devices. Some 80% of those hospitals using intraoperative autotransfusion devices also performed blood salvage postoperatively. The principal use of perioperative blood salvage was in cardiac surgery, orthopaedics, and vascular surgery (90%, 54%, and 54% of departments, respectively). Some 48% of the responding anaesthetists "mostly" considered haemoglobin levels of 8-10 g/dl acceptable in patients without cardiopulmonary disease, but only 18% did so in patients with cardiopulmonary disease. Although available in the majority of hospitals surveyed, the simple techniques of both PABD and isovolaemic haemodilution are unduly neglected in routine clinical practice. The consistent use of both of these techniques, and the careful weighing up of the indication for every single blood transfusion, would not only effectively reduce homologous blood transfusions, but also enable even small hospitals to run successful autologous transfusion programmes without expensive cell-washing and plasmapheresis devices.
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7785750
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[Cerebral vasospasm following aneurysmal subarachnoid hemorrhage. Therapeutic value of treatment with calcium antagonists, hypervolemic hemodilution and induced arterial hypertension].
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Only 53%-58% of patients with a subarachnoid haemorrhage (SAB) following the rupture of a cerebral aneurysm survive without neurological damage. Morbidity and mortality are closely related to the delayed ischaemic neurological deficit due to cerebral vasospasm. The following review gives an account of pathophysiological mechanisms; the importance of treatment with calcium antagonists, hypervolaemic haemodilution, and induced arterial hypertension is discussed in light of the current literature. PATHOPHYSIOLOGY. In addition to other vasoactive substances in the blood, haemoglobin, which is released from lysed erythrocytes on the 2nd to 4th day after the haemorrhage, plays an important role in inducing vasospasm. An inflammatory angiopathy ensues, with complete resolution after 6-12 weeks. The cerebral blood flow (CBF) is reduced depending on the extent of vasospasm. Irreversible infarction may follow the decrease of CBF below a critical value. Severe vasospasm causes autoregulatory disturbances and reduced responsiveness of cerebral vessels to CO2. CALCIUM ANTAGONISTS. The calcium blocker nimodipine causes dilatation of small pial vessels with increased CBF. However, systemic vasodilation with the subsequent fall in blood pressure may limit the increase in CBF. Furthermore, it is known that nimodipine decreases intracellular calcium concentrations resulting in some protection against ischaemic cellular injury. Seven placebo-controlled clinical studies have shown that nimodipine improves the outcome of patients with severe neurological damage due to cerebral vasospasm. HYPERVOLAEMIC HAEMODILUTION. Volume expansion and haemodilution to a hematocrit of 30%-33% is suggested to improve cerebral perfusion during vasospasm. The central venous and pulmonary capillary wedge pressures should be 10-12 mm Hg and 15-18 mm Hg, respectively. But there is no evidence of improved outcome with this measure, and pulmonary edema is a frequent side effect. However, impairment of cerebral perfusion and increased neurological damage can be demonstrated with hypovolaemia and haemoconcentration. INDUCED ARTERIAL HYPERTENSION. In the presence of cerebral vasospasm and resulting autoregulatory disturbances, cerebral perfusion can be increased by raising systemic arterial pressure. This measure, too, fails to improve neurological outcome. CONCLUSION. Treatment of cerebral vasospasm following a SAB aims to avoid any impairment of cerebral perfusion. Hypovolaemia and haemoconcentration have to be corrected. Normoventilation should be established to avoid hypocapnic vasoconstriction. Nimodipine should be administered continuously after a SAB. In view of the autoregulatory disturbances, systemic hypotension with its danger of decreased CBF must be prevented. The importance of hypervolaemic haemodilution and/or induced arterial hypertension is not clear. Despite therapeutic efforts, the number of patients who have survived a SAB without a substantial neurological deficit has not increased.
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7785749
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The pathophysiology of ocular allergy: current thinking.
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Seasonal allergic conjunctivitis is the only ocular disease to involve solely Type-1 hypersensitivity, the other main forms of ocular allergy--perennial allergic conjunctivitis, vernal and atopic keratoconjunctivitis and giant papillary conjunctivitis--each having a more complex immunological basis and a chronic inflammatory component. Involvement of secondary inflammatory cells, particularly eosinophils, in addition to the mast cells resident in the conjunctival substantia propria, can lead to more serious corneal damage with vision-threatening potential. Thoughtful management of allergic conjunctivitis is needed in order to control the ocular inflammation without incurring steroid-induced side-effects, and patient education is also an important factor in maintaining optimal allergen avoidance, especially in the more severe and chronic cases. Laboratory models can be helpful in assessing the potential of new drugs, and SWR mice (topically sensitised and challenged with short ragweed) show clinical signs of allergic conjunctivitis, together with mast cell and eosinophil involvement, remarkably similar to the human pathophysiology. The antiinflammatory activity of both steroids and nedocromil sodium observed in this animal model supports therapeutic evidence of the usefulness of second-generation mast cell stabilising drugs in the treatment of ocular allergy.
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7785748
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Current practice: diagnosis and treatment in primary healthcare.
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In a primary healthcare facility, there are certain 'rules of thumb' that can be recommended for the diagnosis and treatment of conjunctivitis. The type of discharge is a crucial factor in the differential diagnosis and can also be a clue towards the management in primary care. It is important to identify whether the conjunctivitis is an isolated case or part of another disease, and if it is acute or chronic, and I would suggest taking a smear or culture sample whenever possible. When the aetiology is not clear, I would try antibiotics. If the patient is allergic, and an allergic conjunctivitis is suspected, the best management today is to use mast cell stabilisers, and combine these with conservative measures of frequent washings, and compresses. If the aetiology remains doubtful, or if there is no obvious improvement using these treatments, the patient should be re-evaluated and/or referred to an ophthalmologist or specialist eye centre. The use of corticosteroids for conjunctivitis should certainly be avoided in primary healthcare. Conjunctivitis is often self-limited and the drug-induced consequences of improper management can be far more devastating than the disease itself.
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7785747
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Comparative therapeutic studies with Tilavist.
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Comparative clinical trials which include known therapies as well as placebos are essential in constructing a solid basis from which to 'launch' any new drug. This applies especially to eye drops for treatment of seasonal allergic conjunctivitis, where the symptomatology, already dependent on the vagaries of the natural pollen challenge season, is further influenced by a positive washing action of the placebo eye drops. Tilavist (2% nedocromil sodium ophthalmic solution) has therefore been compared with sodium cromoglycate eye drops and non-sedating antihistamine tablets, both mainstays in the treatment of seasonal allergy, in a series of double-masked, placebo-controlled, mainly multicentre studies. Nedocromil sodium, twice or four times daily, proved as effective overall as sodium cromoglycate (2% or 4% four times daily) in three seasonal trials, and was the more effective treatment in a study of patients with vernal keratoconjunctivitis. Its efficacy was most evident during peak periods of pollen challenge, when neither placebo nor sodium cromoglycate eye drops controlled breakthrough symptoms. Three further seasonal studies showed nedocromil sodium eye drops to be as effective as standard oral doses of astemizole and terfenadine, whilst a faster onset of action than terfenadine was reported in one multicentre study.
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7785746
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Clinical experience with Tilavist: an overview of efficacy and safety.
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A programme of clinical studies was carried out to determine the basic efficacy and safety of 2% nedocromil sodium eye drops (Tilavist) in treating allergic conjunctivitis, in 2,905 patients from 3-76 years of age. Results of all the double-masked placebo comparative studies completed to date-five in vernal keratoconjunctivitis (VKC), five in perennial (PAC) and 16 in seasonal allergic conjunctivitis (SAC)-have been assessed in a statistical overview analysis. Nedocromil sodium, administered four times daily to 153 patients with VKC, was significantly more effective than placebo (155 patients) and in the clinicians' opinion gave good control in 76% of cases, compared with 46% for placebo (p < 0.001). Patients with chronic symptoms of PAC also responded better to nedocromil sodium given four times daily (n = 146) rather than twice daily (n = 86), and significantly more patients (p < 0.001) were effectively controlled by four times daily treatment with nedocromil sodium (72%) than with placebo (47%; n = 156). Twice-daily dosage with nedocromil sodium (n = 677) was adequate for SAC, however, and the treatment was statistically better than placebo (p < 0.01-p < 0.001) whether dosed twice or four times daily. Speed of action was assessed in seven SAC studies in which 79% of all patients (n = 295) using nedocromil sodium had experienced relief of symptoms when questioned, half of them within 15 minutes and 74% during the first hour after dosing. Test treatments were well-accepted by both adults and children, and there were no major adverse events. Minor irritations reported more frequently with nedocromil sodium than placebo were stinging or burning of the eyes on application of the drops and a distinctive taste, noted by 5% of the active treatment group (n = 1,552).
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7785737
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[The prevention of the adhesive process after surgical interventions in gynecological patients in the reproductive period].
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Dynamic laparoscopy making use of special tubes was carried out in 149 patients (30 with acute inflammatory diseases of the uterine tubes, 80 following reconstructive surgery on the tubes suffering from tuboperitoneal sterility, 9 operated on the internal genitals). Repeated laparoscopic examinations were carried out in the course of 14 days, every 2-3 days. The course of the postoperative period was assessed by the presence of adhesions, hyperemia, edema, and exudation. Adhesions were separated, during mixtures were delivered including antibiotics, corticosteroids, enzymes, rheopolygluquins; chromohydrotubations was carried out. Dynamic laparoscopy in patients with inflammatory diseases of the internal genitals helped detect positive results 2-3 days after intensive care was started and prevent adhesions. This method appears to be particularly valuable if used after inflammatory processes and interventions on the internal genitals in young, more so in nulliparous women planning to have children in future.
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7785738
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[Changes in the phosphoinositide metabolism in the blood and tissues of benign and malignant uterine tumors].
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Measurements of phosphoinositide levels in the blood, immunocompetent cells, and tumors of 105 patients with uterine myomas, 24 patients with cancer of the corpus uteri, and 17 ones with uterine sarcoma showed that the parameters of phosphoinositide metabolism in the blood of patients with tumors of the uterus reliably differed from those in healthy women. The content of phosphatidylinosites and other phosphoinositide fractions in patients with uterine myomas reliably differed from those in patients with malignant tumors of the uterus, this permitting the use of such measurements in the differential diagnosis. Phosphoinositide mechanism of development of tumors of the uterus is discussed, which is related to the "new" phosphoinositides and secondary messengers directly participating in transfer of cell growth signals.
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7785734
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[The importance of the vertical transmission of enteroviruses in the epidemiology of congenital viral infections].
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A total of 814 newborns were examined using a highly sensitive method of indication of viral antigens. A high incidence of congenital viral infection was revealed: 450 per 1000 live-born children. Enteroviral infections (mainly Coxsackie) ranked first in prevalence. These infections in the newborns are mainly caused by the vertical transmission of enteroviruses from mothers with persistent forms of infections. Virtually all the other viruses (influenza viruses, cytomegalovirus, herpes simplex virus, parainfluenza, measles, and rubella viruses) are detected in the newborns included in the group at a high risk of vertical transmissions of enteroviral infections. In the majority of cases the said viruses were detected in association with enteroviruses.
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7785736
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[The clinical importance of the dopplerometric study of the blood flow in the normal iliac, uterine and ovarian arteries, in myoma and in endometriosis interna of the corpus uteri].
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Dopplerometric investigation of pelvic arteries was carried out in 30 women without gynecologic diseases, in 51 patients with internal endometriosis, and 48 ones with uterine myomas. Internal endometriosis of the uterus was found to be characterized by specific qualitative changes in spectral curves of bloodstream velocity in the internal iliac and uterine arteries. Moreover, progressive changes in spectral curves related to dissemination of endometrioid heterotopias were revealed. In patients with uterine myomas combined with internal endometriosis disorders of peripheral circulation typical of endometriosis predominated.
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7785733
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[The steroid content of the amniotic fluid in the 1st and 2nd pregnancy trimesters in 21-hydroxylase insufficiency and in fetal central nervous system defects].
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A total of 103 samples of amniotic fluid obtained by transabdominal amniocentesis were examined, 52 of these from women at a high risk of giving birth to children with congenital adrenal hyperplasia due to 21-hydroxylase (21-OH) deficiency and 30 ones with fetuses with different neural tube malformations. 17-Hydroxyprogesterone was found to be a reliable marker indicating the disease in fetuses from the group at risk of hereditary 21-OH deficiency. This marker can be effectively used as early as in the 1 gestation trimester. Fetal CNS defects are associated with hypofunction of the adrenal cortex in the II gestation trimester, observed in 60-63% of cases with hydrocephalus, anencephaly, or microcephaly. Since the function of fetal adrenals is of paramount importance for the development and maturation of a fetus, it should be examined in case of developmental defects of the neural tube, in order to predict the effect of prenatal treatment.
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7785732
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[A prospective study of antipyrine pharmacokinetics in pregnancy].
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Pharmacokinetics of a single dose of antipyrin (10 mg/kg) subjected to biotransformation at the expense of microsomal oxidation of its molecule in the liver was studied in 6 healthy nonpregnant women and in 24 women within the frames of a prospective follow-up starting from the early terms of gestation; 7 of these women developed edemas, proteinuria and/or hypertension in the course of follow-up. The results permit us consider that a test with a single antipyrin dose may be used as a marker to characterize drugs with similar metabolic transformations when used in pregnant women. The identity of pharmacokinetic regularities of antipyrin in samples of blood plasma and saliva permit the use of saliva as biological material for assessment of the metabolic profile of pregnant women. The problem of drug therapy in the third trimester is closely connected with specific features of pharmacokinetic profile detected by antipyrin test both in normal and complicated gestation. Our data evidence that the third trimester is characterized by special tension of the metabolic processes. A complicated course is associated with unambiguous changes in the metabolic activity of drugs, this necessitating special attention of a physician to drug dose.
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7785731
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[The transplacental passage and distribution of ceftazidime in the fetal and maternal organs in a 2nd-trimester abortion].
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Transplacental passage of ceftazidime was studied in 17 women with second-trimester pregnancy which had to be discontinued for medical causes. A single intramuscular injection of the antibiotic resulted in creation of therapeutically active concentrations in fetal blood and organs, amniotic fluid, and placenta. Transplacental passage of ceftazidime from the mother to the fetus was 19.12%, diffusions to the amniotic fluid 14.46%, diffusion to the placenta 48.46%. Ceftazidime may be effective for the prevention and therapy of fetal intrauterine infection and chorioamnionitis.
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7785728
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Brief communication: estimation of adult stature from the calcaneus and talus.
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Calcanei and tali of 100 skeletons in the Hamann-Todd Collection at the Cleveland Museum of Natural History were measured. The skeletons represented 50 males and 50 females distributed equally by race, i.e., whites and blacks. Linear-regression equations, with standard errors ranging from 4.09 to 6.11 cm, were derived from these measurements for the purpose of estimating stature. Two independent control samples, including one comprised of remains of American servicemen lost in World War II and the Korea and Vietnam wars, were tested with relatively accurate results.
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7785727
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Enamel hypoplasia in the middle pleistocene hominids from Atapuerca (Spain).
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The prevalence and chronology of enamel hypoplasias were studied in a hominid dental sample from the Sima de los Huesos (SH) Middle Pleistocene site at the Sierra de Atapuerca (Burgos, northern Spain). A total of 89 permanent maxillary teeth, 143 permanent mandibular teeth, and one deciduous lower canine, belonging to a minimum of 29 individuals, were examined. Excluding the antimeres (16 maxillary and 37 mandibular cases) from the sample, the prevalence of hypoplasias in the permanent dentition is 12.8% (23/179), whereas the deciduous tooth also showed an enamel defect. No statistically significant differences were found between both arcades and between the anterior and postcanine teeth for the prevalence of hypoplasias. In both the maxilla and the mandible the highest frequency of enamel hypoplasias was recorded in the canines. Only one tooth (a permanent upper canine) showed two different enamel defects, and most of the hypoplasias were expressed as faint linear horizontal defects. Taking into account the limitations that the incompleteness of virtually all permanent dentitions imposes, we have estimated that the frequency by individual in the SH hominid sample was not greater than 40%. Most of the hypoplasias occurred between birth and 7 years (N = 18, X = 3.5, SD = 1.3). Both the prevalence and severity of the hypoplasias of the SH hominid sample are significantly less than those of a large Neandertal sample. Furthermore, prehistoric hunter-gatherers and historic agricultural and industrial populations exhibit a prevalence of hypoplasias generally higher than that of the SH hominids. Implications for the survival strategies and life quality of the SH hominids are also discussed.
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7785726
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Pattern profile analysis of hominid and chimpanzee hand bones.
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In a study designed to complement morphological research on hominid hand bones, length and width measurements of the thumb, index, and middle rays were obtained from radiographs of modern human hands. These rays are primary in precision-gripping postures and are therefore the ones most relevant for investigating evolutionary changes in fine manipulation. Pattern profile analysis allows individuals or samples to be plotted against a reference sample in standard deviation units, or Z-scores. It provides an indication of how different measurements are from modern human averages, while taking into consideration the degree of variation present within modern human samples. A pattern profile for chimpanzees is clearly distinct from humans but quite similar to that of a bonobo, demonstrating the promise of pattern analysis. Partial pattern profiles of several of the more complete early hominid bones from Hadar, Swartkrans, and Olduvai (O.H. 7) are presented and compared. Hadar bones are long and wide at midshaft relative to articular widths; both body-size effects and functional differences are likely. Thumb distal phalanges from Swartkrans and Olduvai both have relatively small base widths, but they differ in other proportions. Two first metacarpals from Swartkrans show distinct patterns. The profiles of La Ferrassie I and Shanidar IV show the characteristically large Neanderthal distal phalanges. Profiles of Skhul IV and Predmost III are alike in some regions with reference to modern North American white males, though they are less similar overall than are those of the two Neanderthals.
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7785725
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Nonlinearity in the relationship between bone Sr/Ca and diet: paleodietary implications.
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Strontium in archaeological human bones is widely, almost paradigmatically, used as a measure of the relative dietary abundances of plants and meat. Quantitative modeling reveals, however, that there is not a simple proportional relationship between bone strontium and the dietary plant/meat ratio. While knowledge of specific foods and their compositions may permit accurate calculation of average bone strontium levels, knowledge of bone strontium does not inversely allow accurate calculation of specific foods. Although bone strontium quantitatively reflects the average dietary Sr/Ca ratio, it is disproportionately sensitive to high-calcium foods and can be easily affected by minor dietary constituents and culinary practices. Bone strontium, and by analogy, barium, should be seen as a reflection of the high-mineral dietary components rather than a quantitative index of trophic position.
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7785724
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Sexual dimorphism in the snub-nosed langurs (Colobinae: Rhinopithecus).
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Sexual dimorphism in the dentition and skeleton of the four extant species of snub-nosed langurs, Rhinopithecus (R.) bieti, R. (R.) brelichi, R. (R.) roxellana and R. (Presbytiscus) avunculus, was studied. The species shared a similar general pattern of sexual dimorphism, but were found to differ in respects that appear to reflect the influence of disparate socioecological and environmental factors. All the species showed marked canine dimorphism but the very high degree of canine dimorphism in R. bieti appeared to be due to the intensity of intermale competition for mates during a temporally restricted breeding season, and possibly also to the intensity of competition between males for other resources during other times of the year. Sexual dimorphism in the postcranial skeleton of Rhinopithecus species was also most pronounced in R. bieti and may be related to the relatively higher frequency of terrestrial locomotion in males of the species.
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7785723
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Faunal assemblage seriation of southern African Pliocene and Pleistocene fossil deposits.
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Fossil assemblages from the Pliocene and Pleistocene of southern Africa were seriated in order to give a better idea of their relative chronology. Time-sensitive mammals were selected for calculation of the Faunal Resemblance Index among 17 site units. On the basis of a logistical seriation and subsequent site analysis, the following sequence of sites was deemed most probable: Makapansgat Member 3, Makapansgat Member 4, Taung Dart deposits, Sterkfontein Member 4 and Taung Hrdlicka deposits, Sterkfontein Member 5 (in part) and Kromdraai B, Kromdraai A and Swartkrans Member 1, Swartkrans Member 2, Swartkrans Member 3, Plovers Lake, Cornelia, Elandsfontein Main Site, Cave of Hearths Acheulian levels, Florisbad and Equus Cave and Klasies River Mouth.
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7785722
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Ohalo II H2: a 19,000-year-old skeleton from a water-logged site at the Sea of Galilee, Israel.
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The discovery of well-preserved human remains at the site of Ohalo II in the northern Jordan Valley substantially augments the meager fossil record of the Levantine late Upper Pleistocene. The Ohalo II H2 specimen, dated to ca. 19,000 B.P., is the most complete early Epipaleolithic hominid discovered in Israel and promises to contribute to the clarification of a number of problematic issues in the local evolution of anatomically modern humans. In addition to a description of the burial and its Kebaran context, a detailed anatomical description of the skeleton is offered and morphometric comparisons are made to other Upper Paleolithic hominids. Ohalo II H2 is shown to demonstrate affinities in the craniofacial skeleton to fossils from the early Upper Paleolithic and late Epi-Paleolithic of the Levant.
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7785720
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Vestibular rehabilitation with graded occupations.
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These three case reports are examples of the use of graded, purposeful activities in remediating the symptoms of vestibular disorders. Therapists can design individualized treatment plans for each patient by incorporating activities of interest to the patient. The treatment activities must include the particular head movements and positions that elicit vertigo during assessment. Additionally, activities must be interesting to the individual patient. Use of interesting activities may sustain the patient's interest and motivation for the treatment program and enable the patient to relate the learning process to real life experience. The principle that graded, repetitive head movement exercise is efficacious in reducing vertigo and disequilibrium in patients with vestibular disorders is now well accepted among physicians and therapists who treat these patients. The principle of adding meaning or purpose to otherwise rote exercise is well accepted among occupational therapists and is supported by evidence from the empirical literature (Heck, 1988; Kircher, 1984; Yoder, Nelson, & Smith, 1989). This concept of adding purpose to repetitive exercise may now be extended to the treatment of patients with peripheral vestibular disorders.
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7785718
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A group approach to mental health fieldwork.
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Fieldwork opportunities in mental health settings are limited and difficult to find. There is increased pressure for occupational therapy supervisors to accept more students although they have less time to devote to them. This article describes a group approach to training occupational therapy students that was used at one fieldwork site. The occupational therapy staff members were each responsible for specific teaching assignments that allowed them to work with a number of students simultaneously. Program development and evaluation meetings created an alternative forum for exploring ideas and practice issues and for providing guidance and supervision. This approach reduced the amount of time each therapist spent with students, provided students with several role models, and encouraged independent thinking in students.
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7785717
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Using the case method to develop clinical reasoning skills in problem-based learning.
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Clinical reasoning is increasingly recognized as a crucial component of the occupational therapy process. Different types of clinical reasoning used by occupational therapists have been identified, including scientific, procedural, interactive, narrative, conditional, and pragmatic reasoning. This article describes the use of the case method in the University of New Mexico undergraduate occupational therapy curriculum to facilitate development of occupational therapy students' problem-solving and reasoning abilities. The case method is a component of problem-based learning that emphasizes small group work to solve clinical problems that are presented as case studies. Students are presented with a variety of case formulas including paper or written cases, videotape cases, simulated client cases, and real client cases to promote the development of specific types of clinical reasoning. Problem-based learning may also hold promise as an educational strategy for fieldwork students and clinicians.
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7785716
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A problem-based learning curriculum for occupational therapy education.
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To prepare practitioners and researchers who are well equipped to deal with the inevitable myriad changes in health care and in society coming in the 21st century, a new focus is needed in occupational therapy education. In addition to proficiency in clinical skills and technical knowledge, occupational therapy graduates will need outcome competencies underlying the skills of critical reflection. In this article, the author presents (a) the rationale for the need for change in occupational therapy education, (b) key concepts of clinical reasoning and critical reflection pertaining to the outcome such change in occupational therapy education should address, (c) problem-based learning as a process and educational method to prepare occupational therapists in these competencies, and (d) the experience of the Program in Occupational Therapy at Shenandoah University in Winchester, Virginia, in implementing a problem-based learning curriculum.
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7785715
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Functional capacity evaluations of persons with chronic fatigue immune dysfunction syndrome.
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Chronic Fatigue Immune Dysfunction Syndrome (CFIDS) is estimated to affect 2 to 5 million people in the United States. Despite its high incidence, persons with CFIDS have been neglected by the medical community mainly because there is no singular confirming diagnostic test or proven effective treatment. The CFIDS population is incorrectly stereotyped as upper-middle-class, white, female hypochondriacs; consequently, symptoms often are belittled or ignored. In reality, CFIDS is a severe medical condition that affects women, men, and children of any race and often causes long-term or total disability. The results of a modified functional capacity evaluation developed by the author and completed on 86 persons with CFIDS between 1988 and 1990 confirm that this population has severe physical and cognitive disabilities that affect their professional, familial, and social lives. The results of these evaluations are used to present a profile of persons with CFIDS that can serve as a basis for understanding this population and for guiding intervention.
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7785714
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Spherical grip strength in children 3 to 6 years of age.
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The purpose of this study was to establish normative data on spherical grip strength of children 3 to 6 years of age with the Martin Vigorimeter. Two hundred twenty-five preschoolers in the Kalamazoo, Michigan, area were tested with standardized positioning and instructions. The mean of three trials for each hand was used as the grip-strength score. A repeated measure design was used and the right and left hands were alternated during testing to allow a 20-sec rest period between trials. Hand width also was measured in inches from the head of the second metacarpal to the head of the fifth metacarpal. Hand width and grip strength were significantly correlated for both the right (p < .0001) and the left hands (p < .001). Grip strength increased linearly across all of the age groups (p < .001). The results of paired t tests did not show a significant difference in grip strength between the right and left hands or between boys and girls. A table of mean grip-strength scores and hand width measurements along with their standard deviations is presented for clinical use. The vigorimeter could be used to assess the grip strength of children with rheumatic disorders without putting excessive pressure on the joints or skin of the hand.
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7785712
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Building inclusive community: a challenge for occupational therapy. 1994 Eleanor Clarke Slagle Lecture.
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Occupational therapy was founded on values of choice, relevance, and active participation in meaningful occupations. To assure choice in daily living, learning, work, and play for persons with disabilities or significant health issues, occupational therapy practitioners are challenged to gain increased understanding of the unique culture and community of each person and family with whom they work; create opportunities for these persons to develop their capabilities in community settings of their choice; promote more interactive models of practice in which the practitioner affects the arrangements between the person and society; work with communities to welcome the gifts of diversity; and develop skill in analyzing environments and facilitating environmental interaction. The environment category of the spatiotemporal adaptation theory is expanded and a communication model for collaboration in building individual community is proposed as means for addressing the challenges.
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7785713
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Reasoning and the art of therapy for spinal cord injury.
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In this pilot study, qualitative methodology was used to examine the clinical reasoning of four experienced occupational therapists as they presented and modified therapeutic activities to treat patients with spinal cord injuries. The therapists demonstrated the multi-layered thinking discovered in previous research, but hierarchical structuring of knowledge emerged as an unexpectedly dominant theme in their reasoning. Examples of hierarchical thinking about therapeutic activity included creating mental files of therapy tasks and materials sequenced from elementary to advanced and determining the level of difficulty at which to present an activity in order to build the patient's skills in a stepwise manner. The therapists reported that they learned to make decisions about the use of activities in treatment by observing skilled clinicians and by treating patients.
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7785706
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Horner's syndrome in subadventitial carotid artery dissection and the role of magnetic resonance angiography.
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A 47-year-old man with a postganglionic Horner's syndrome and severe right facial pain was found to have a normal carotid angiogram. We obtained a magnetic resonance angiogram of the neck because of our continued clinical suspicion of dissection. An area of hyperintensity was identified along the lumen of the right internal carotid artery, suggesting a subadventitial dissection. Magnetic resonance angiography is a noninvasive, sensitive technique for identifying some carotid dissections.
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7785705
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Tonic pupil and orbital glial-neural hamartoma in infancy.
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Tonic pupils in early childhood are rare. We studied an otherwise healthy 31/2-month-old girl who had a right pupil that was poorly reactive to light, without other signs of oculomotor nerve palsy. Constriction of the right pupil after instillation of 0.125% pilocarpine eyedrops confirmed denervation hypersensitivity, consistent with a tonic pupil. There was no strabismus or proptosis. A magnetic resonance imaging scan demonstrated a right orbital mass, interposed between the lateral and inferior recti muscles. Biopsy was consistent with a benign, glial-neural hamartoma. Thus, in this young patient, a tonic pupil was associated with a benign orbital mass.
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7785703
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Branch retinal vein occlusion in a child with ocular sarcoidosis.
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A 13-year-old girl had unilateral iridocyclitis and periphlebitis. The periphlebitis exacerbated, and macular edema as well as branch retinal vein occlusion developed. The patient was treated with systemic corticosteroids. The lesions responded well to systemic corticosteroids. Histologic diagnosis of sarcoidosis was obtained by transbronchial lung biopsy. Ocular lesions in this child were similar to those seen in adult sarcoidosis. Branch retinal vein occlusion may occur as a rare vascular complication of sarcoidosis.
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7785704
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Duane's retraction syndrome associated with chromosome 4q27-31 segment deletion.
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A 15-year-old boy with bilateral blepharoptosis, bilateral type 1 Duane's retraction syndrome, and mild learning difficulties underwent chromosomal analysis. A de novo deletion of a segment of the long arm of chromosome 4 (4q27-31) was found. To our knowledge, no other individuals with this chromosome deletion have Duane's retraction syndrome. The chromosome defect lies close to the epidermal growth factor gene, 4q25, which was recently linked to Rieger's syndrome. We suggest that families with Duane's retraction syndrome should be assessed for linkage to the area of 4q27-31.
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7785702
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White-centered retinal hemorrhages as an early sign of preeclampsia.
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We examined a pregnant patient who had symptomatic white-centered retinal hemorrhages. Severe preeclampsia rapidly developed despite the patient not having hypertension, proteinuria, or edema at initial examination. Retinal hemorrhages gradually resolved without treatment and visual acuity returned to 20/20 six months after emergency delivery of a healthy infant. Retinal or choroidal vascular abnormalities in pregnant patients may be caused by early preeclampsia and immediate obstetric referral is indicated.
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7785701
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Scleromalacia after retinal detachment surgery.
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A 34-year-old man developed severe scleral thinning with imminent prolapse after conventional retinal detachment repair, including pars plana vitrectomy, endolaser photocoagulation, and perfluoropropane injection. Cadaveric dura mater was used to repair the scleral defect. The cause of scleromalacia in this case remains to be determined. Commercially prepared cadaveric dura mater can be successfully used as a tectonic graft for the treatment of scleral thinning.
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7785699
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Psoriatic corneal abscess.
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We examined a patient with psoriasis and stromal infiltrate that was treated with topical corticosteroids. The patient gradually improved and the stromal infiltrate diminished. The cause of psoriasis and its ocular manifestations remains unknown. A corneal abscess without epithelial infiltration that responds to topical corticosteroid therapy may represent a specific ocular manifestation of psoriasis.
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7785700
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Asymmetric canthaxanthin retinopathy.
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We studied a case of crystalline retinopathy occurring after prolonged use of oral canthaxanthin. The patient was followed up for 38 months during which time she sustained a branch retinal vein occlusion in her left eye. An asymmetric appearance to the crystalline deposition was noted with increased sedimentation seen in the left eye. Vascular alterations after a branch retinal vein occlusion may lead to local stasis that may exacerbate the development of canthaxanthin retinopathy.
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7785698
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Infection after radial keratotomy.
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Eight years after eight-incision radial keratotomy, a corneal ulcer developed around the inferotemporal incision in an otherwise healthy 39-year-old man. There was no history of corneal trauma or contact lens wear. Both Fusarium and Acanthamoeba organisms were eventually isolated from the ulcer. A therapeutic keratoplasty was performed. Inferotemporal incisions may be predisposed to epithelial breakdown and infection many years after radial keratotomy.
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7785697
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Possible role of herpes simplex virus in the origin of Posner-Schlossman syndrome.
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We conducted this study to determine if the herpesviruses are possible etiologic agents in Posner-Schlossman syndrome. We aspirated aqueous humor samples from patients during acute attacks of the syndrome. Ten normal aqueous humor specimens from patients undergoing cataract surgery were used as controls. DNA was extracted and subjected to polymerase chain reaction amplification and Southern blot hybridization. All three specimens were positive for amplified genomic fragments of herpes simplex virus and negative for varicella-zoster virus and cytomegalovirus. Ten normal aqueous specimens were negative for all three. Herpes simplex virus may play a role in the origin of Posner-Schlossman syndrome.
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7785696
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Diagnostic criteria for Graves' ophthalmopathy.
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To propose criteria for the diagnosis of Graves' ophthalmopathy. We reviewed the evolution of nomenclature describing Graves' ophthalmopathy. and the diagnostic schema used in key published reports. A laboratory test or clinical finding pathognomonic for Graves' ophthalmopathy currently is not available or recognized. Extant diagnostic criteria may exclude appropriate cases. Graves' ophthalmopathy is considered to be present if eyelid retraction occurs in association with objective evidence of thyroid dysfunction or abnormal regulation, exophthalmos, optic nerve dysfunction, or extraocular muscle involvement. The ophthalmic signs may be unilateral or bilateral, and confounding causes must be excluded. If eyelid retraction is absent, then Graves' ophthalmopathy may be diagnosed only if exophthalmos, optic nerve involvement, or restrictive extraocular myopathy is associated with thyroid dysfunction or abnormal regulation and if no other cause for the ophthalmic feature is apparent.
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7785695
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No demonstrated effect of pre-enucleation irradiation on survival of patients with uveal melanoma.
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To evaluate the hypothetical effect of pre-enucleation irradiation on survival of patients with uveal melanoma. In a prospective study between 1978 and 1990, 145 patients with uveal melanoma were treated by irradiation in two fractions of 4 Gy before enucleation. A historical control group of 89 patients with uveal melanoma treated by enucleation alone was operated on between 1971 and 1990. Patients were followed up until December 1992 or until death. The mean follow-up period was 65 months in the irradiated group and 88 months in the control group. The preoperatively irradiated group of patients showed no significant improvement of the survival rate after 7 1/2 years (75.9%) compared with the control group (72.1%). Preoperative irradiation was not associated with survival (P = .93), as assessed by Cox proportional hazard analysis, adjusted for age, gender, tumor location, tumor size, cell type, and year of enucleation. Women in both the irradiated and control groups had a better prognosis than men (P = .002). Preoperative irradiation in this nonrandomized study had no effect on survival of patients with uveal melanoma.
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7785694
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Metastatic tumors to the pituitary.
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To illustrate how the ophthalmologist can distinguish a metastatic tumor to the pituitary from a pituitary adenoma through clinical, particularly ophthalmic, findings. We studied three patients with metastatic disease to the pituitary. One patient had a history of breast cancer without known metastatic disease, and two patients had no previous diagnosis of malignancy. We reviewed the literature with respect to signs and symptoms that may differentiate such lesions from histologically benign pituitary adenomas. Including our patients and the recent cases in the literature, 42% of patients with metastatic tumors had oculomotor palsies, compared with less than 5% of patients with pituitary adenomas. Of patients with metastatic tumors, 33% had diabetes insipidus, compared with 1% who had pituitary adenomas. Furthermore, with respect to differentiating a pituitary adenoma from a metastatic process, radiographic examinations were not helpful, and histopathologic examination was occasionally incorrect. The ophthalmologist can potentially differentiate a metastatic tumor to the pituitary from a pituitary adenoma, thereby assisting in the proper treatment of patients.
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7785693
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Vancomycin levels in the vitreous cavity after intravenous administration.
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We studied the effects of inflammation, repeated antibiotic doses, and the surgical status of the eye on penetration of vancomycin hydrochloride into the rabbit vitreous cavity after intravenous administration. We studied three anatomic states (phakic, aphakic, and aphakic, vitrectomy-treated eyes) subdividing each into inflamed and noninflamed groups. Intravenous vancomycin hydrochloride (15 mg/kg of body weight) was administered every 12 hours for 48 hours. Eyes were harvested for the assay of vitreous cavity antibiotic levels at various intervals from one to 49 hours. We determined concentrations and calculated mean values and S.E.M. Therapeutic levels were not established in the vitreous cavity at any time period in the two phakic groups. At 25 hours, the inflamed aphakic eyes had concentrations of 5.05 +/- 1.9 micrograms/ml and the control noninflamed aphakic eyes 4.5 +/- 1.23 micrograms/ml; slight increases were found by 49 hours. Concentrations tested in the aphakic, vitrectomy-treated eyes at two, 13, 25, and 49 hours demonstrated progressive increases both in the inflamed eyes (5.4 +/- 2.4 micrograms/ml, 9.64 +/- 4.25 micrograms/ml, 9.2 +/- 3.96 micrograms/ml, 10.34 +/- 4.49 micrograms/ml) and noninflamed eyes (3.52 +/- 2.1 micrograms/ml, 5.4 +/- 1.96 micrograms/ml, 6.8 +/- 2.53 micrograms/ml, 8.7 +/- 5.44 micrograms/ml). Vitreous vancomycin concentrations in aphakic and aphakic, vitrectomy-treated eyes after intravenous administration exceed the minimal inhibitory concentrations for the usual gram-positive pathogens that create endophthalmitis, suggesting a role for intravenous vancomycin in the treatment of bacterial endophthalmitis.
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7785692
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Accidental Nd:YAG laser injuries to the macula.
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To study the clinical course of accidental, single-focus Nd:YAG laser injuries to the macula. We reviewed the clinical course of five eyes (four patients) that sustained macular injuries from a Nd:YAG laser. All patients were examined within 24 hours of injury and were observed without surgical intervention for a mean of 20 months (range, 12 to 32 months). A single full-thickness foveal or parafoveal retinal hole was apparent in all eyes either on initial examination or within two weeks of injury. All macular holes were within 650 microns of the foveal center. The mean final visual acuity was 20/60 (range, 20/25 to 20/400) and was related to the distance between the macular hole and the foveal center. None of the eyes developed either subretinal neovascularization or clinically significant epiretinal membrane formation during the study period. Despite initial poor visual acuity in patients who had a full-thickness foveal or parafoveal retinal hole, visual acuity improved without treatment when the site of the laser injury was located outside the foveal center.
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7785691
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Quantitation of retinal ablation in proliferative diabetic retinopathy.
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We studied 294 eyes of 182 patients, to quantitate the amount of retinal ablation required for regression of proliferative diabetic retinopathy. Eyes included in the study had two or more proliferative diabetic retinopathy risk factors, received panretinal photocoagulation, and had a minimum follow-up of one year. Laser photocoagulation or cryotherapy was given to eyes that failed to regress or had progression of retinopathy. Eyes treated by other physicians, treated with xenon arc photocoagulation, or undergoing laser treatment or vitrectomy for other retinal conditions were excluded. The total area of retina ablated was calculated and used as a quantitative measure of treatment. Regression was observed in 275 eyes (93%); 19 eyes (7%) failed to regress and eventually required vitrectomy. Panretinal photocoagulation alone successfully led to regression in 229 eyes (77%), whereas 46 eyes (15.6%) required both photocoagulation and peripheral anterior retinal cryotherapy. An average of 1.7 treatments per eye led to regression. Eyes were bimodally distributed by requirement for treatment, into low and high treatment groups. Low treatment eyes received an average of 510 mm2 of retinal ablation (2,600 500-microns burns), and high treatment eyes, 1,280 mm2 (6,500 500-microns burns). More extensive treatment was required with more retinopathy risk factors (P = .002 for four vs three risk factors and P = .0007 for four vs two risk factors); duration of diabetes mellitus longer than 15 years (P = .004), and onset of diabetes mellitus before 30 years of age (P = .0008). Patients with proliferative diabetic retinopathy should be treated aggressively with panretinal photocoagulation, cryotherapy, or both. The amount of initial treatment required for regression may be considerably more than that recommended by the Diabetic Retinopathy Study.
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7785689
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Diode laser photocoagulation for threshold retinopathy of prematurity in eyes with tunica vasculosa lentis.
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To determine possible side effects of diode laser photocoagulation for threshold retinopathy of prematurity in eyes with tunica vasculosa lentis. In a prospective clinical study, threshold retinopathy of prematurity was treated in 14 eyes of seven consecutive preterm infants with tunica vasculosa lentis (birth weight, 480 to 980 g; mean +/- S.D., 777 +/- 175 g; gestational age, 24 to 27 weeks; mean +/- S.D., 25.7 +/- 0.9 weeks) by using the diode laser indirect ophthalmoscope. Main outcome measure was the incidence of adverse treatment effects. Follow-up included anterior segment examination with a hand-held slit lamp and ranged from seven to 17 months (12.6 +/- 3.5 months). The tunica vasculosa lentis did not interfere with photocoagulation in any of the 14 eyes. Laser power ranged from 200 to 400 mW (260 +/- 52 mW). Duration of a single spot was 200 msec. Number of burns ranged from 1,060 to 2,132 (1,556 +/- 315). Retinopathy of prematurity regressed in all eyes, and the outcome was a flat, attached retina. A small amount of postoperative anterior chamber bleeding was noticed in one eye (7% of the eyes, 14% of the patients). There were neither lenticular opacities nor cataract formation. Diode laser photocoagulation with the laser indirect ophthalmoscope can be used safely in eyes with tunica vasculosa lentis. At the laser energy levels used in our study, no transient lens opacities or cataract formation occurred. However, the results of this study are limited by a relatively small number of patients and a relatively short follow-up.
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7785690
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Reappraisal of biomicroscopic classification of stages of development of a macular hole.
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To update the biomicroscopic classification and anatomic interpretations of the stages of development of age-related macular hole and provide explanations for the remarkable recovery of visual acuity that occurs in some patients after vitreous surgery. Recent biomicroscopic observations of various stages of macular holes are used to postulate new anatomic explanations for these stages. Biomicroscopic observations include the following: (1) the change from a yellow spot (stage 1-A) to a yellow ring (stage 1-B) during the early stages of foveal detachment is unique to patients at risk of macular hole; (2) the prehole opacity with a small stage 2 hole may be larger than the hole diameter; and (3) the opacity resembling an operculum that accompanies macular holes is indistinguishable from a pseudo-operculum found in otherwise normal fellow eyes. The change from a yellow spot (stage 1-A) to a yellow ring (stage 1-B) is caused primarily by centrifugal displacement of retinal receptors after a dehiscence at the umbo. The hole may be hidden by semiopaque contracted prefoveolar vitreous cortex bridging the yellow ring (stage 1-B occult hole). Stage 1-B occult holes become manifest (stage 2 holes) either after early separation of the contracted prefoveolar vitreous cortex from the retina surrounding a small hole or as an eccentric can-opener-like tear in the contracted prefoveolar vitreous cortex, at the edge of larger stage 2 holes. Most prehole opacities probably contain no retinal receptors (pseudo-opercula). Surgical reattachment of the retina surrounding the hole and centripetal movement of the foveolar retina induced by gliosis may restore foveal anatomy and function to near normal.
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7785688
|
The prevalence of dissociated vertical deviation in patients with sensory heterotropia.
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We reviewed 281 consecutive patients with sensory esotropia or exotropia to determine the prevalence of dissociated vertical deviation in patients with sensory strabismus. We reviewed the charts of all patients who received a diagnosis of sensory heterotropia or dissociated vertical deviation and who were examined at the Pediatric Ophthalmology Service at the Texas Children's Hospital between 1973 and 1992. Statistical analyses of the prevalence of dissociated vertical deviation were determined after evaluating the direction of the accompanying horizontal strabismus and examining the temporal relationship of the unilateral vision loss. Dissociated vertical deviation was diagnosed in 35 patients (12.5%). It occurred more frequently in sensory esotropia (22 patients, 18.3%) than exotropia (13 patients, 8.1%) (P = .009). The age at which unilateral visual loss occurred did not influence the development of dissociated vertical deviation. Dissociated vertical deviation in patients with acquired loss of vision does not support the contention that dissociated vertical deviation is a genetically predetermined anomaly of binocular vision.
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7785687
|
The effect of cleaning and disinfection of soft contact lenses on corneal infectivity in an animal model.
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Bacterial contamination of previously worn soft contact lenses, especially at sites of lens deposits, might play a role in the pathogenesis of lens-associated bacterial keratitis. We studied the effects of three commercial contact lens cleaners and disinfectants in a rabbit model to determine whether cleaning and disinfection reduced infectivity. Duragel 75 soft contact lenses, designed to fit the eyes of rabbits, were worn by rabbits under tarsorrhaphies, then were removed and cleaned in one of three cleaner and disinfectant solutions according to the manufacturers' instructions. The lenses were contaminated by overnight incubation in a suspension of 10(8) Pseudomonas aeruginosa/ml and were placed under tarsorrhaphies on the eyes of fresh rabbits. The rabbits were observed for two weeks for signs of infection. Control rabbits wore new, uncleaned but contaminated lenses or worn, uncleaned but contaminated lenses. The rates of infection with the three commercial cleaner and disinfectant solutions ranged from 18% (two of 11) to 31% (four of 13); these incidences were not significantly different from one another or from the 19% (three of 16) incidence with new, contaminated but uncleaned lenses. By contrast, when worn, uncleaned but contaminated lenses were placed in rabbits' eyes, seven of eight were infected, a rate that is significantly higher than that of the other four groups (P = .0003). These data indicate that the three commercial lens cleaner and disinfectant solutions were of similar efficacy in reducing the infectivity of contaminated contact lenses to a level similar to that of new, unworn lenses.(ABSTRACT TRUNCATED AT 250 WORDS)
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7785686
|
Refractive changes at extreme altitude after radial keratotomy.
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We studied the effects of altitude on four corneas that had undergone radial keratotomy and four normal corneas exposed to increasing elevation during a high-altitude excursion. We measured visual acuity, cycloplegic refraction, keratometry, and intraocular pressure at sea level and after 24-hour exposure to 12,000 and 17,000 ft. We observed a significant increase in spherical equivalence (hyperopic shift) in radial keratotomy eyes exposed to altitude as compared to controls (P < .0001). The average change in spherical equivalent cycloplegic refraction from sea level to 12,000 ft was 1.03 +/- 0.16 diopters and from sea level to 17,000 ft was 1.94 +/- 0.26 diopters. We also observed a significant decrease in keratometry values at altitude as compared with control corneas (P < .0001). The average change in keratometry from sea level to 12,000 ft was 0.59 +/- 0.19 diopter and from sea level to 17,000 ft was 1.75 +/- 0.27 diopters. Although the specific origin of these changes is open to question, we hypothesize that hypoxic corneal expansion in the area of the radial keratotomy incisions may lead to central corneal flattening and a hyperopic shift in refractive error. The cornea that has undergone radial keratotomy appears to adjust constantly to changing environmental oxygen concentration, producing a new refractive error over a period of 24 hours or more. Additional study is required to identify with certainty the specific origin of the hyperopic shift at high altitude.
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7785685
|
Assessment of the power and height of radial aspheres reported by a computer-assisted keratoscope.
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The two purposes of this study were (a) to assess the accuracy with which a keratoscope, the Topographic Modeling System (TMS-1), calculated the heights and powers of rotationally symmetric, radially aspheric test surfaces and (b) to determine whether the TMS-1 used an axial solution for radius of curvature to determine the power of a sphere that would produce the same semichord as would the test surface on a keratograph. The TMS-1 heights and powers were studied for four test surfaces that had radial profiles similar to those of normal corneas. The powers of the surfaces were calculated from the local radius of curvature derived from the surfaces' manufacturing formulas. The heights and powers that would result from an axial solution were calculated in a TMS-1 simulator. TMS-1 data were compared with data from the surfaces' formulas and with data from the simulation. The TMS-1 data were almost identical to the heights and powers calculated from the simulated axial solution. The TMS-1 data were similar to the heights and powers calculated from the mathematical formulas from the apex to 2 mm from the apex but differed by up to 85 microns of height and 10 diopters of power in the periphery. The TMS-1 appeared to use the axial solution that does not calculate power from local radius of curvature. Clinicians should use caution when inferring corneal shape from power maps based on an axial solution, especially outside the central 2-mm radius of a normal cornea, because such power does not depict corneal curvature.
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7785683
|
Membranous outgrowth suggesting lens epithelial cell proliferation in pseudophakic eyes.
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We sought to determine the incidence and structure of membranous outgrowth, which extends from the anterior capsular opening onto the intraocular lens surface in pseudophakic eyes. Thirty-four eyes of 31 patients with age-related cataract were prospectively studied. No patient had any abnormality other than cataract. Each patient underwent continuous circular capsulorhexis, phacoemulsification, and implantation within the capsule of a three-piece posterior chamber lens. A slit lamp and specular microscope were used to observe and photograph the intraocular lens surface and anterior capsular opening every day for the first postoperative week, and at days 14, 21, and 28. We counted the number of eyes with the membranous outgrowth and graded the outgrowth according to its shape and length at each postoperative period. In total, 27 of 34 (79%) eyes had the membranous outgrowth from the anterior capsular opening onto the intraocular lens surface. The membrane was first observed on day 3. Three of 34 eyes had the dendritic or fan-shaped structure, which extended less than 0.5 mm from the capsular edge. The membranes were most frequently found on day 7. Twenty-five of 34 eyes had the outgrowth in various grades. After four weeks, no membranes were observed. The time course and structure of the membranous outgrowth we observed were comparable to those of the outgrowth of lens epithelial cells under tissue culture conditions. The membranous outgrowth may be the result of a transient but active proliferation of human lens epithelial cells onto the intraocular lens surface.
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7785682
|
Color Doppler ultrasound analysis of ocular circulation after topical calcium channel blocker.
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To investigate the effect of topical administration of the calcium channel blocker verapamil on intraocular pressure and retrobulbar hemodynamics. In this randomized, prospective, double-masked study, we examined the effects of single-dose topical administration of verapamil in ten normal human volunteers by using color Doppler ultrasound imaging to measure hemodynamic parameters. Limitations of this study include single-dose application of verapamil and relatively small sample size. No systemic effect on heart rate or blood pressure was detected after administration of topical verapamil. The intraocular pressure significantly decreased compared with baseline two hours after topical 0.125% and 0.25% verapamil (P = .015 and .040, respectively). Pourcelot's ratio, an index of vascular resistance, measured in the central retinal artery was significantly reduced after topical application of 0.125% verapamil (P = .008). The change in Pourcelot's ratio primarily resulted from an increased end diastolic velocity in the central retinal artery. No significant differences compared with baseline values were detected in the color Doppler ultrasound measurements of the posterior ciliary arteries and the central retinal vein two hours after topically administered verapamil. Topical administration of verapamil decreases intraocular pressure and alters ocular hemodynamics, reducing the vascular resistance index in the central retinal artery.
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7785684
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The effect of artificial tears on computer-assisted corneal topography in normal eyes and after penetrating keratoplasty.
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To examine the effect of adding artificial tears for one minute to normal eyes and eyes that have undergone keratoplasty by using computer-assisted videokeratography. We prospectively analyzed 24 normal corneas (24 patients) chosen by random number table (reproducibility section [10 eyes], tear section [14 eyes]) as well as 14 postkeratoplasty corneas. The parametric descriptors analyzed statistically included the simulated keratometry value, surface asymmetry index, surface regularity index, power at the vertex normal, and the pupil offsets from the visual axis. Vectoral analysis was used to calculate the difference in power and axis between the simulated keratometry values before and after tear instillation. In normal eyes, tear instillation increased the surface asymmetry index (0.28 +/- 0.34, P = .01), changed the simulated keratometry value (0.23 diopter by 27.8 degrees), and power (0.79 +/- 0.82 diopters, P = .004) and location (0.91 +/- 0.76 mm) of the steepest point of the cornea changed. In postkeratoplasty eyes, the surface regularity index decreased (0.49 +/- 0.80, P = .04), surface asymmetry index decreased (0.37 +/- 1.03, P = .21), mean simulated keratometry value changed (1.04 diopters by 1.01 degrees), and power (0.70 +/- 2.34 diopters, P = .28) and location (1.04 +/- 1.17 mm) of the steepest point of the cornea changed. Changes were greater than the variability of the surface regularity index (0.07 +/- 0.05), surface asymmetry index (0.04 +/- 0.03), simulated keratometry value power (0.08 +/- 0.06 diopter), and axis (4.6 +/- 5 degrees). The addition of artificial tears to normal or regular and symmetric eyes that have undergone keratoplasty worsened symmetry and changed the power and location of the steepest point. However, the addition of artificial tears to irregular eyes that have undergone penetrating keratoplasty created a more regular and symmetric surface and significantly altered the simulated keratometry values. We recommend that corneal topography be performed before the application of artificial tears.
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7785681
|
Color Doppler imaging and spectral analysis of the optic nerve vasculature in glaucoma.
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We used color Doppler imaging to study blood flow velocity in the central retinal artery and the short posterior ciliary arteries in patients with glaucoma. Fifty-two patients with chronic open-angle glaucoma, 24 patients with normal-tension glaucoma, and 28 normal subjects were studied. The mean of the peak systolic velocity, the end diastolic velocity, and the resistive index were compared in the three groups. Compared with the normal subjects, the patients with chronic open-angle glaucoma showed a statistically significant (P < .05) decrease in the mean end diastolic velocity and an increase in the mean resistive index in all vessels studied. The patients with normal-tension glaucoma showed similar changes, achieving significance most prominently in the central retinal arteries, compared with normal subjects (P < .05). There were no statistically significant differences between the patients with chronic open-angle glaucoma and those with normal-tension glaucoma. Open-angle glaucoma appears to be associated with a decreased mean flow velocity and an increased mean resistive index in the ocular vasculature. These changes are in keeping with possibly compromised circulation in this region.
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7785679
|
Control sampling strategies for case-crossover studies: an assessment of relative efficiency.
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The case-crossover study design is a method to assess the effect of transient exposures on the risk of onset of acute events. Control information for each case is based on his/her past exposure experience, and a self-matched analysis is conducted. Empiric evaluation of five approaches to the analysis of case-crossover data from a study of heavy physical exertion and acute myocardial infarction onset is shown. The data presented are from the Onset Study, a case-crossover study of the determinants of myocardial infarction onset conducted in 45 centers from August 1989 to October 1992. In model 1, exactly one control period (matched on clock-time) was sampled per case. In models 2-4, up to 25 control periods were sampled, and the effect of clock-time on the baseline hazard of infarction was modeled. In model 5, a census of the person-time experienced by each subject over the year preceding the infarction was sampled. The 95% confidence interval for model 1 was 2.7 times wider, and the relative efficiency, defined as v infinity/vM, where vM represents the asymptotic variance estimate of the estimated log relative risk with M control periods sampled per case, was only about 14% of model 5. In models 2-4, the efficiency increased with the number of control periods, regardless of the modeling assumptions. Even with many control periods sampled, models 2-4 achieved only half the efficiency of model 5. The control sampling strategy in any given case-crossover study should be selected with the trade-offs between precision and potential biases of the estimates in mind.
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7785678
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Fetal growth retardation in sudden infant death syndrome (SIDS) babies and their siblings.
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To evaluate the intrauterine growth potential of infants that die from sudden infant death syndrome (SIDS), the authors compared SIDS infants with their surviving siblings. The SIDS sibships themselves were also compared with sibships where all infants survived. Data from the population-based Medical Birth Registry of Norway, with 1.3 million births during 1967-1988, were used. From the birth cohorts, 1,984 SIDS cases were identified. All births were linked into sibships. The mean birth weight and gestational age were calculated across sibships of different sizes for first to fourth birth order. In a further analysis, birth weights were standardized to adjust for gestational age. Mothers of SIDS infants give birth to smaller babies in general. SIDS infants weighed, on average, 85 g less at birth than their siblings and 164 g less compared with babies in nonaffected sibships. When birth weights were standardized for gestational age, most of the weight difference between SIDS infants and siblings was due to a shorter gestational age of SIDS infants, while the difference between surviving siblings of SIDS infants and births from nonaffected sibships remained. All births in sibships with a SIDS infant were intrauterine growth retarded. This may reflect factors that contribute to SIDS risk (such as maternal smoking). The factors that contribute to shorter gestational age and further slowing of growth in the SIDS infants may specifically influence the SIDS infant and not its siblings.
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7785677
|
Irritable bowel syndrome in a community: symptom subgroups, risk factors, and health care utilization.
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The clinical relevance of subdividing the irritable bowel syndrome (IBS) into subgroups based on bowel habit is largely unknown. We therefore obtained an age- and sex-stratified random sample of Olmsted County, Minnesota, residents aged 20-95 years. All subjects were mailed a valid self-report questionnaire during the years 1988-1993; the response rate was 74% (n = 3,022). Among subjects with IBS (n = 536), four symptom-based subgroups of similar size were identified: constipation predominant, diarrhea predominant, alternating constipation and diarrhea, and neither. The prevalence of IBS was significantly greater in females, primarily because of a higher prevalence of constipation-predominant IBS in women. Of persons > or = 60 years of age, 23% reported the initial onset of IBS in the previous year compared with 10% in younger subjects; the age at onset of IBS was similar among the subgroups. Marital status, education level, smoking, and alcohol use were not significantly different among the subgroups. Of those with IBS, 25% reported visiting a physician for abdominal pain or disturbed defecation in the prior year compared with only 8% of persons without IBS. Female sex, an increased number of Manning's symptom criteria, and the individual IBS subgroups were not associated with higher rates of physician visits. We conclude that the onset of IBS may not be limited to early adulthood and that subgroups of IBS based on bowel patterns may not identify clinically distinct entities.
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7785676
|
Incidence of benign gastrointestinal tumors among atomic bomb survivors.
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Using the Hiroshima and Nagasaki tumor and tissue registries, benign tumors of the stomach, colon, and rectum were identified among members of the Life Span Study cohort of atomic bomb survivors. During the period 1958-1989, a total of 470 cases with histologically confirmed benign gastrointestinal tumors (163 stomach, 215 colon, and 92 rectum) were identified among approximately 80,000 Life Span Study members with known radiation doses, who were alive in 1958. Restricting the analysis to adenomatous tumors not detected at autopsy, a dose-response relation was observed for stomach tumors (excess relative risk at 1 sievert (ERR1Sv) = 0.53; 95% confidence interval (CI) -0.01 to 1.43). However, there was little evidence of a dose response for colon tumors (ERR1Sv = 0.14; 95% CI -0.20 to 0.76), and no evidence was present for rectal tumors (ERR1Sv = -0.25; 95% CI undetermined to 0.80). The excess relative risk (ERR) for benign tumors of the stomach is consistent with the excess found for stomach cancer. For cancer of the rectum, the dose response was not significant, but the point estimate of the excess relative risk was positive. The excess relative risk for benign colon tumors is less than that reported for colon cancer (ERR1Sv = 0.72). The authors observed a dramatic increase in colon tumors detected after 1985, suggesting that the relatively recent introduction of colonoscopy may be influencing these results.
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7785675
|
Effects of question order on estimates of the prevalence of attempted weight loss.
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Although numerous surveys have been conducted to estimate the prevalence of attempted weight loss, little information is available on the possible effects of question order on the prevalence estimates. The authors examined data collected from 231,852 respondents to surveys conducted in the District of Columbia and 20 states that participated in the Behavioral Risk Factor Surveillance System between 1985 and 1992. In surveys conducted from 1985 to 1988, respondents (n = 117,827) were first asked their body weight and then were asked if they were trying to lose weight; 48% of the women and 29% of the men reported that they were trying to lose weight. In 1989, 1991, and 1992 (no questions about weight control were asked in 1990), the order of the questions was reversed so that respondents (n = 114,025) were asked whether they were trying to lose weight before they were asked to report their weight; 41% of the women and 26% of the men reported that they were trying to lose weight. The authors conclude that survey respondents, especially women, may be more likely to report that they are trying to lose weight when questions about weight control practices immediately follow questions on current weight. This apparent effect of question order points to the need for caution in comparing prevalence estimates across surveys in which the questions are not asked in a similar order, even when the questions are worded identically.
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7785674
|
Relation of body fat distribution to ischemic heart disease. The National Health and Nutrition Examination Survey I (NHANES I) Epidemiologic Follow-up Study.
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Although an excess of adipose tissue in the abdominal and truncal regions is associated with various metabolic alterations, relatively few cohort studies have examined its importance in the development of ischemic heart disease, and little information is available from black populations. The authors examined the relation of central obesity, as characterized by a thick subscapular skinfold relative to the triceps skinfold, to the incidence of ischemic heart disease among 9,822 persons in the Epidemiologic Follow-up Study of the National Health and Nutrition Examination Survey I; baseline data were collected in 1971-1975 and follow-up was through 1987. We found that, independently of relative weight, cigarette smoking, and other covariates, the hazard rate ratios for ischemic heart disease incidence contrasting the upper and lower quintiles of central obesity were 1.75 (95% confidence interval 1.3-2.3) among women and 1.65 (95% confidence interval 1.3-2.2) among men. Although central obesity was related similarly to disease among white and black men, the association among women differed between whites (rate ratio = 1.94) and blacks (rate ratio = 0.73); p = 0.002 for race x the central obesity product term. Additional research is needed to clarify the relation of various anthropometric measurements to ischemic heart disease, particularly among blacks, but the assessment of fat distribution may help identify high-risk persons for whom weight loss might be most beneficial.
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7785673
|
Coronary heart disease mortality and sudden death: trends and patterns in 35- to 44-year-old white males, 1970-1990.
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Trends in coronary heart disease mortality and sudden death were studied in 35- to 44-year-old white male residents of Allegheny County, Pennsylvania. Deaths coded as any cardiac or vascular disease, diabetes, unexplained sudden death, and other rubrics were eligible for investigation, and the cause of death was validated by physicians examining multiple data sources about the deaths. During 1970-1990, 1,424 white male deaths were investigated, with 903 validated as coronary heart disease. In that time span, white male coronary heart disease mortality fell from 93.4 to 36.7 per 100,000 population per year, a 60% decline. Little proportionate change was seen in characteristics of the deaths, which were predominantly sudden and out-of-hospital. Diabetes mellitus history increased proportionately over time, largely because diabetics' mortality rates, unlike those of all other subgroups, did not fall. These observations support the contention that the decline in coronary heart disease mortality relates to risk factor modification more than to improvements in the treatment of coronary heart disease. Differences in death certification practices must be considered when interpreting and comparing vital statistics data.
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7785672
|
Clustering of risk habits in young adults. The Cardiovascular Risk in Young Finns Study.
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The authors studied the occurrence of common lifestyle risk factors, namely, nonprudent diet, smoking, physical inactivity, and frequent inebriation by alcohol in a cohort of young adults aged 18, 21, and 24 years (n = 484) as part of the Cardiovascular Risk in Young Finns Study in 1986. Risk habits showed significant clustering; the number of subjects was greater than expected in groups with zero and three of four risk habits and less than expected in the group with only one or two risk habits. Stepwise logistic regression analysis was used to find independent determinants for this clustering from a set of socioeconomic, demographic, and behavioral (type A components) determinants. The logistic model suggested several independent risk factors for risk habit clustering. These included male sex, aggressiveness, and past unemployment. Paying a lot of attention to health habits, higher education (being a student), good self-perceived health, and a high sense of responsibility seemed to be protective factors against risk habit clustering. The accumulation of risk habits was also associated with an atherogenic lipid and blood pressure profile (clustering of high density lipoprotein cholesterol/total cholesterol ratio, triglycerides, and diastolic blood pressure in their extreme tertiles). These findings show that common risk habits cluster among young adults. Knowledge about the determinants of this clustering will aid in the planning of future preventive strategies against cardiovascular diseases in young people.
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7785670
|
Air pollution and hospital admissions for cardiovascular disease in Detroit, Michigan.
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In the December 1952 smog disaster in London, a substantial increase in mortality was closely associated with the increase in air pollution. Deaths from cardiovascular causes were elevated as well as respiratory deaths. The increase was greatest in the elderly. Hospital admissions were increased for both respiratory and cardiovascular diseases. Since then, many studies have reported associations between lower concentrations of air pollution and daily mortality. Little attention has been paid to the question of hospital admissions for cardiovascular illness, however. This study examined the association between air pollution and cardiovascular hospital admissions for persons aged 65 years and older in the Detroit, Michigan, metropolitan area during the years 1986-1989. After controlling for seasonal and other long-term temporal trends, temperature, and dew point temperature, the particulate matter with an aerodiameter of < or = 10 microns (PM10) was associated with daily admissions for ischemic heart disease (relative risk (RR) = 1.018, 95% confidence interval (CI) 1.005-1.032 for an interquartile range (32 micrograms/m3) increase in pollution). SO2, CO, and ozone made no independent contribution to ischemic heart disease admissions. Both PM10 (RR = 1.024, 95% CI 1.004-1.044) and CO (RR = 1.022, 95% CI 1.010-1.034 for an interquartile range (1.28 ppm) increase in pollution) showed independent associations with heart failure admissions. These results were robust to alternate methods of estimation and weather control.
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7785669
|
Associations between ambient particulate sulfate and admissions to Ontario hospitals for cardiac and respiratory diseases.
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The association of daily cardiac and respiratory admissions to 168 acute care hospitals in Ontario, Canada, with daily levels of particulate sulfates was examined over the 6-year period 1983-1988. Sulfate levels were recorded at nine monitoring stations in regions of southern and central Ontario spanned by three monitoring networks. A 13-micrograms/m3 increase in sulfates recorded on the day prior to admission (the 95th percentile) was associated with a 3.7% (p < 0.0001) increase in respiratory admissions and a 2.8% (p < 0.0001) increase in cardiac admissions. Increases were observed for all age groups examined. Admissions for cardiac diseases increased 2.5% for those under 65 years and 3.5% for those 65 years and older. After adjusting for ambient temperature and ozone, similar increases in respiratory admissions were observed in the period from April to September (3.2%) and in the period from October to March (2.8%). A 3.2% increase was observed for cardiac admissions in the period from April to September, and a 3.4% increase was observed in the period from October to March after adjusting for ambient temperature and ozone.
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7785662
|
Posttransplantation lymphoproliferative disorders in solid organ recipients are predominantly aggressive tumors of host origin.
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Patients immunosuppressed after organ transplantation have an increased frequency of lymphoproliferative disorders, known as posttransplantation lymphoproliferative disorders (PTLDs). In recipients of bone marrow allografts. PTLDs are often of donor origin. In only a few cases of lymphoma arising in solid-organ transplant recipients has the origin from host or donor lymphocytes been established. The authors have analyzed 11 cases of PTLD from Massachusetts General Hospital, arising in seven male and four female patients, aged 8 to 63, five with renal, four with cardiac, and two with hepatic allografts. Using the polymerase chain reaction (PCR) to investigate genetic polymorphism at the D4S174 locus on chromosome 4, the Rb1.20 locus on chromosome 13, and the D19S178 locus on chromosome 19, only one tumor (previously reported) was of donor origin, whereas 10 were of host origin. Follow-up revealed that six patients died of PTLD, one was alive with recurrent PTLD, and four were alive and well or had died of other causes, including the patient with donor-origin PTLD. Based on these cases and on a review of previously reported cases, the authors conclude that the majority of PTLDs in solid organ recipients are of host origin. There appears to be a trend toward a greater likelihood of persistent or recurrent PTLD among solid organ recipients with host-origin tumors than among those with donor-origin tumor.
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7785663
|
Lymphocytosis of gamma/delta T cells in human ehrlichiosis.
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The majority of T cells in peripheral blood express a T-cell receptor (TCR) comprised of alpha and beta chains. An alternate form of the TCR is comprised of gamma and delta chains. These gamma/delta T cells are associated with certain infectious lesions, and modestly elevated in peripheral blood in certain disease states. Human ehrlichiosis is characterized by hematologic abnormalities including multi-lineage cytopenias. In most cases reported, a lymphocytopenia has been present either at diagnosis, or at some time during the illness. Early in the course of antibiotic treatment (48-72 hours), the lymphocytopenia corrects itself and is rapidly followed by a lymphocytosis of T cells that express CD3, but are negative for CD4 and CD8, as well as the major form of the TCR formed by the alpha/beta heterodimer. Instead, these CD3+4-8- T cells express the gamma/delta heterodimer associated with V gamma 9 and V delta 2 chains, a population of cells usually the distinctive minority of peripheral blood T cells, but constituting the major phenotype of peripheral gamma/delta T cells.
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7785661
|
The effect of a heparin removal filter on platelet aggregation studies in heparin-induced thrombocytopenia.
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Patients having a heparin-associated platelet antibody who are receiving heparin at the time of testing for heparin-induced thrombocytopenia (HIT) by platelet aggregometry may exhibit aggregation in the negative control channel. Filtering plasma to remove the heparin in may produce a nonaggregating negative control channel. The effect of the Pall Hepchek (Pall Biomedical, East Hills, NY) heparin removal filter on platelet aggregation studies was evaluated. Samples were studied from 10 patients with clinically established HIT. The pre-filtration platelet aggregation studies were unequivocally positive for heparin antibody. The remainder of each sample was filtered and the aggregation studies were repeated. Of the four patients on IV heparin, only one remained positive post-filtration. Of the six patients receiving subcutaneous heparin or flushes, one remained strongly positive, one was borderline, and four became negative. Pall Hepchek heparin filtration unpredictably alters the results of platelet aggregation studies, and should not be used routinely to remove heparin in the presence of aggregation in the negative control.
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7785660
|
Platelet satellitism is Fc gamma RIII (CD16) receptor-mediated.
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Platelet satellitism (PS), the phenomenon of platelet rosetting around polymorphonuclear neutrophils (PMN), which is observed in ethylenediamineetetraacetic acid (EDTA)-anticoagulated blood at room temperature, is caused by the presence of IgG autoantibodies in the serum. Fourteen patients with PS were studied, and the presence of both EDTA-dependent antiplatelet and EDTA-dependent antineutrophil IgG (auto)antibodies were found in their sera. Anti-neutrophil activity was completely abolished when the sera were absorbed on normal platelets, which suggests that a single antibody is involved. Inhibition studies with monoclonal antibodies indicated that this IgG autoantibody is directed against the glycoprotein IIb/IIIa complex of the platelet membrane, as well as the neutrophil Fc gamma receptor III (Fc gamma RIII). In addition, the antibody did not react with platelets from a patient with type I Glanzmann's disease, nor with neutrophils from a patient with congenital Fc gamma RIII absence (NAnull phenotype), thus confirming both specificities. As in other literature cases, a clear correlation between the presence of this IgG and a specific clinical situation, disease, or use of drugs could not be shown. Therefore, these antibodies, which are present in some normal individuals, might occur naturally. Because of the exposure of particular cryptoantigenic structures present on EDTA-modified platelet and PMNs, they may manifest themselves by triggering the PS phenomenon.
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7785659
|
Heparin-induced increase in the international normalized ratio. Responses of 10 commercial thromboplastin reagents.
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A clinician's concern about an erratic response to oral anticoagulation in a patient treated concurrently with heparin and warfarin led the authors to investigate the effect of heparin on INR values obtained with various commercial thromboplastin reagents. Studies conducted with pooled normal plasma and with pooled plasma from patients treated long-term with oral anticoagulants demonstrated a wide range of sensitivities to heparin of these reagents as characterized by prolongation of INR values. Innovin was unaffected by concentrations of heparin as high as 1 U/mL. In contrast, Ortho thromboplastin showed the greatest increase in INR values over the range of heparin concentrations studied. Three other thromboplastins including Neoplastine CI, Dade thromboplastin, and Simplastin A demonstrated only limited sensitivity to heparin. Prolongation of the INR by heparin was reversed by protamine in a dose-related manner and also by preincubation of the plasma with heparinase. Some patients treated with warfarin while on the authors' institutional protocol for heparin had plasma concentrations greater than 0.8 U/mL. When thromboplastin reagents sensitive to heparin were used with such specimens, the INR values obtained were falsely elevated. The authors suggest that reagents insensitive to heparin be employed to avoid this difficulty.
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