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7788303
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Antiproliferative actions of 7-substituted 1,3-dihydroxyacridones; possible involvement of DNA topoisomerase II and protein kinase C as biochemical targets.
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7-Chloro-1,3-dihydroxyacridone (1) reversibly inhibited growth of KB and vero cell lines with IC50's of 35 and 40 microM, respectively, and a topoisomerase II-mediated multidrug resistant KB sub-clone was found to be about three-fold more susceptible to 1. In contrast, two cell lines of lymphoid origin were killed following treatments with 60 microM and at higher concentrations of 1. KB cell growth inhibition correlated with a rapid, reversible suppression of thymidine incorporation. Uridine but not leucine incorporation was also rapidly suppressed. The in vitro activities of DNA topoisomerase II and novel protein kinase C-subtype delta were inhibited at effective concentrations in tissue-culture, but 1 did not stimulate intracellular protein-associated DNA breaks nor interfere initially with topoisomerase II-mediated DNA cleavage in KB cells. In addition to antiproliferative effects against cells, the compound was weakly virustatic for herpes simplex virus type I with an IC50 of 8 microM. Limited studies comparing three 1-congeners and citpressine-I, an acridone alkaloid with reported antiherpes activity, demonstrated that 7-substituted 1,3-dihydroxyacridones are novel antiproliferative agents which share similar biological and biochemical properties.
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7788305
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Structurally designed novel furogamma lactams as inhibitors for bacterial propagations.
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Some novel furogamma lactams have been synthesised by one step condensation of arylaminomalonates with substituted furyl acryloyl chlorides. The annulation of substituted monocyclic gammalactams followed by cyclization produced novel tricyclic furogamma lactams. Some of these furogammalactams are found to exhibit Gram-positive and Gram-negative antibacterial activity at very high concentrations.
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7788304
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Phage display of catalytically active staphylococcal nuclease.
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Staphylococcal nuclease (SNase), a 14 kD enzyme that catalyzes the hydrolysis of single- and double-stranded nucleic acid, was fused to the N-terminus of the gene III (pIII) protein of filamentous phage fdtet. The SNase-pIII protein is infective and the catalyzes DNA hydrolysis, demonstrating that functional SNase can be displayed on the phage surface.
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7788301
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Iron(II)/reductant(DH2)-induced activation of dioxygen for the hydroxylation and ketonization of hydrocarbons; mimics for the cytochrome P-450 hydroxylase/reductase system.
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Several metal complexes [(FeII(DPAH)2 (DPAH2 = 2,6-dicarboxyl pyridine), FeII(PA)2 (PAH = picolinic acid), FeII(bpy)2(2+), FeII(OPPh3)4(2+), (Cl8TPP)FeIIIX (X = Cl, OH, SCH2Ph) [Cl8TPP = tetrakis (2,6-dichlorophenyl)porphyrin], (TPP) FeIIICl (TPP = tetraphenylporphyrin), and CuI(tpy)2+ (typ = 2,2'-6,2"-terpyridine)] in combination with one of several reductants [DH2; PhNHNHPh (mimic of dihydroflavin), PhNHNH2, ascorbic acid (H2asc), and PhCH2SH (model ligand for cysteine residue)] catalytically activate O2 (1 atm) for the hydroxylation of saturated hydrocarbons (e.g. c-C6H12-->c-C6H11OH). This chemistry closely parallels that of cytochrome P-450 proteins, and both appear to involve a Fenton-like reactive intermediate), [LxFeOOH(DH)]. With cyclohexane as the substrate the dominant product is its ketone (as well as significant amounts of its hydroperoxide). 1,4-Cyclohexadiene (with two double-allylic carbon centers) undergoes dehydrogenation to give benzene, but also yields substantial amounts of phenol via ketonization of an allylic carbon. The 1:1 FeII(bpy)2(2+)/(PhNHNH2 or H2asc), FeII(PA)2/H2asc, and (Cl8TPP)FeIIICl/PhNHNH2 combinations initiate the autoxidation of 1,4-cyclohexadiene with turnover numbers (moles of product per mole of reductant) from 71 to 26, respectively (alpha-tocophenol reduces the turnover numbers by 20-80%). With respect to aerobic biology, the present results indicate that dysfunctional transition metals (degradation products of metalloproteins) in combination with biological reductants activate O2 for reaction with organic substrates. The level of activation is similar to that for Fenton reagents and cytochrome P-450 hydroxylases. Hence, dysfunctional transition metals, reductants, and O2 are a hazardous combination within a biological matrix.
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7788302
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Synthesis of novel water-soluble 7-(aminoacylhydrazono)-formyl camptothecins with potent inhibition of DNA topoisomerase I.
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Eighteen new water-soluble 7-(aminoacylhydrazono)-formyl camptothecins were synthesized and evaluated for their ability to cause protein-linked DNA breaks and to inhibit topoisomerase I activity. Compared with camptothecin, five of the compounds were as potent or more potent in these tw assays but were less toxic in several cancer cell lines. The results suggest that the 7 position in the B ring is a suitable location for introducing a polar moiety into camptothecin producing analogues with enhanced topoisomerase I inhibiting activity.
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7788300
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Synthesis, absolute configuration, conformational analysis and binding affinity properties of enantiomeric forms of DAU 5750, a novel M1-M3 muscarinic receptor antagonist.
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Both the enantiomeric forms of DAU 5750, a novel muscarinic receptor antagonist, have been synthesized in order to assess the relevance of configurational/conformational features for high affinity binding to muscarinic receptor subtypes. The attribution of absolute stereochemistry and conformational analysis by means of molecular modelling and NMR techniques are also reported.
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7788299
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A novel biotinylated heterobifunctional cross-linking reagent bearing an aromatic diazirine.
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The synthesis of a p-[(3-trifluoromethyl)diazirine-3-yl]benzoic acid derivative is described as a new carbene generating heterobifunctional cross-linking reagent. The cross-linker carries a biotin moiety in order to make use of avidin-biotin technology for specific manipulation of cross-linked components. To evaluate the ability of this reagent, the inter-subunit cross-linking of egg-white avidin tetramer was investigated. As a typical application of avidin-biotin technology for cross-linking experiments, a chemiluminescent detection method was examined to identify photobiotinylated components. A cross-linked dimeric product with an apparent molecular mass of 38 kDa was clearly visualized by the combined use of a horseradish peroxidase-streptavidin conjugate and a luminol-based chemiluminescent system.
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7788296
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The catalytic site of serine proteinases as a specific binding cavity for xenon.
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Under moderate pressure, xenon can bind to proteins and form weak but specific interactions. Such protein-xenon complexes can be used as isomorphous derivatives for phase determination in X-ray crystallography. Investigation of the serine proteinase class of enzymes shows that the catalytic triad, the common hydrolytic motif of these enzymes, is a specific binding site for one xenon atom and shows high occupancy at pressures below 12 bar. Complexes of xenon with two different serine proteinases, elastase and collagenase, were analyzed and refined to 2.2 A and 2.5 A resolution, respectively. In both cases, a single xenon atom with a low temperature factor is located in the active site at identical positions. Weak interactions exist with several side chains of conserved amino acids at the active site. Xenon binding does not induce any major changes in the protein structure and, as a consequence, crystals of the xenon complexes are highly isomorphous with the native protein structures. Xenon is also found to bind to the active site of subtilisin Carlsberg, a bacterial serine proteinase, that also has a catalytic triad motif. As the region around the active site shows conserved structural homology in all serine proteinases, it is anticipated that xenon binding will prove to be a general feature of this class of proteins.
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7788298
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Potential radioprotective agents--IV. Schiff bases.
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Twelve Schiff bases were prepared using salicylaldehyde, one with 5-chlorosalicylaldehyde, one with benzaldehyde, and a series of anilines substituted in the m- or p-positions. They were assayed for radioprotective activity in male, Swiss mice irradiated with a nearly lethal dose (950 cGy) of 6 mV photons produced by a linear accelerator, and were compared with the parent amines. Schiff base formation reduced toxicity of the parent amines; its effect on radioprotective activity was erratic, increasing activity in some cases, decreasing activity in others, and having no effect in still others. Radioprotective activity appears to be unrelated to a number of molecular descriptors. The highest radioprotection (100%) was observed for mixtures of p-aminopropiophenone with its Schiff base, or with the Schiff base of 1-(p-aminophenyl)-1-propanol (95%).
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7788297
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Appraisal of a glycopeptide cloaking strategy for a therapeutic oligopeptide: glycopeptide analogs of the renin inhibitor ditekiren.
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Among the limitations to the practical therapeutic oligopeptide are low oral availability, indifferent aqueous solubility, and an astonishing efficient sequestration and biliary elimination by a multi-capacity liver transporter. Given the purposed use of N- and O- linked saccharides as functional appendages of eukaryotic peptides and proteins, a strategy of glycopeptide mimicry was examined for the oligopeptide renin inhibitor, ditekiren. The anticipation was that the saccharide would impart significant aqueous solubility, and might impact beneficially on the remaining two limitations. Execution of this approach was achieved by the removal of the (dimethylethoxy)carbonyl amino terminus of ditekiren, and its substitution by Boc-L-asparagine N-linked mono- and disaccharides. Potent hypotensive activity, as measured by a human renin-infused rat assay, is observed for virtually all of these structures (N-linked beta-pyranose D-N-acetyglucosaminyl, D-glucosaminyl, D-N-acetylgalactosaminyl, D-mannosyl, D-galactosyl, D-maltosyl, D-cellobiosyl, D-chitobiosyl, but not L-fucosyl). The basis for this dramatic improvement (relative to ditekiren in the same assay) is the diversion of the peptide clearance from rapid liver biliary clearance to slower urinary clearance (Fisher, J. F.; Harrison, A. W.; Wilkinson, K. F.; Rush, B. R.; Ruwart, M. J. J. Med. Chem. 1991, 34, 3140). Guided by the human renin-infused rat hypertension assay, an evaluation of the linker-saccharide pairing was made. Loss of hypotensive activity is observed upon substitution of the Boc-L-asn by Boc-D-asn, and by removal of the Boc amino terminus of the glycopeptide. Potent hypotensive activity is preserved by replacement of the Boc-L-asn linker by succinate, malate, tartrate, and adipate linkers. With the longer adipate spacer, attachment of the saccharide to the P-3 phenylalanine--with omission of the P-4 proline--retains activity. These data suggest value to the glycopeptide guise for preserving the in vivo activity, and for the beneficial manipulation of pharmacodynamics, of this renin inhibitory oligopeptide. This strategy may have general applicability.
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7788295
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Solution structure of human thioredoxin in a mixed disulfide intermediate complex with its target peptide from the transcription factor NF kappa B.
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Human thioredoxin is a 12 kDa cellular redox protein that plays a key role in maintaining the redox environment of the cell. It has recently been shown to be responsible for activating the DNA-binding properties of the cellular transcription factor, NF kappa B, by reducing a disulfide bond involving Cys62 of the p50 subunit. Using multidimensional heteronuclear-edited and hetero-nuclear-filtered NMR spectroscopy, we have solved the solution structure of a complex of human thioredoxin and a 13-residue peptide extending from residues 56-68 of p50, representing a kinetically stable mixed disulfide intermediate along the reaction pathway. The NF kappa B peptide is located in a long boot-shaped cleft on the surface of human thioredoxin delineated by the active-site loop, helices alpha 2, alpha 3 and alpha 4, and strands beta 3 and beta 4. The peptide adopts a crescent-like conformation with a smooth 110 degrees bend centered around residue 60 which permits it to follow the path of the cleft. In addition to the intermolecular disulfide bridge between Cys32 of human thioredoxin and Cys62 of the peptide, the complex is stabilized by numerous hydrogen-bonding, electrostatic and hydrophobic interactions which involve residues 57-65 of the NF kappa B peptide and confer substrate specificity. These structural features permit one to suggest the specificity requirements for human thioredoxin-catalyzed disulfide bond reduction of proteins.
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7788294
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Structure of uncomplexed and linoleate-bound Candida cylindracea cholesterol esterase.
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Candida cylindracea cholesterol esterase (CE) reversibly hydrolyzes cholesteryl linoleate and oleate. CE belongs to the same alpha/beta hydrolase superfamily as triacylglycerol acyl hydrolases and cholinesterases. Other members of the family that have been studied by X-ray crystallography include Torpedo californica acetylcholinesterase, Geotrichum candidum lipase and Candida rugosa lipase. CE is homologous to C. rugosa lipase 1, a triacylglycerol acyl hydrolase, with which it shares 89% sequence identity. The present study explores the details of dimer formation of CE and the basis for its substrate specificity. The structures of uncomplexed and linoleate-bound CE determined at 1.9 A and 2.0 A resolution, respectively, reveal a dimeric association of monomers in which two active-site gorges face each other, shielding hydrophobic surfaces from the aqueous environment. The fatty-acid chain is buried in a deep hydrophobic pocket near the active site. The positioning of the cholesteryl moiety of the substrate is equivocal, but could be modeled in the hydrophobic core of the dimer interface. The monomer structure is the same in both the complexed and uncomplexed crystal forms. The dimers differ in the relative positions of the two monomers at the dimer interface. Of the 55 residues that are different in CE from those in C. rugosa lipase 1, 23 are located in the active site and at the dimer interface. The altered substrate specificity is a direct consequence of these substitutions.
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7788293
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Crystal structure of the C2 fragment of streptococcal protein G in complex with the Fc domain of human IgG.
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Streptococcal protein G comprises two or three domains that bind to the constant Fc region of most mammalian immunoglobulin Gs (IgGs). Protein G is functionally related to staphylococcal protein A, with which it shares neither sequence nor structural homology. To understand the competitive binding of these two proteins to the Fc region, the crystal structure of a single Ig-binding domain of streptococcal protein G was determined at 3.5 A resolution in complex with the Fc fragment of human IgG and compared with the structures of protein A:Fc and protein G:Fab complexes. Protein G binds to the interface between the second and third heavy chain constant domains of Fc, which is roughly the same binding site used by protein A. Protein G comprises one alpha-helix packed onto a four-stranded beta-sheet. Residues from protein G that are involved in binding are situated within the C-terminal part of the alpha-helix, the N-terminal part of the third beta-strand and the loop region connecting these two structural elements. The identified Fc-binding region of protein G agrees well with both biochemical and NMR spectroscopic data. However, the Fc-binding helices of protein G and protein A are not superimposable. Protein G and protein A have developed different strategies for binding to Fc. The protein G:Fc complex involves mainly charged and polar contacts, whereas protein A and Fc are held together through non-specific hydrophobic interactions and a few polar interactions. Several residues of Fc are involved in both the protein G:Fc and the protein A:Fc interaction, which explains the competitive binding of the two proteins. The apparent differences in their Fc-binding activities result from additional unique interactions.
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7788292
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Crystal structure of the MS2 coat protein dimer: implications for RNA binding and virus assembly.
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The coat protein in RNA bacteriophages binds and encapsidates viral RNA, and also acts as translational repressor of viral replicase by binding to an RNA hairpin in the RNA genome. Because of its dual function, the MS2 coat protein is an interesting candidate for structural studies of protein-RNA interactions and protein-protein interactions. In this study, unassembled MS2 coat protein dimers were selected to analyze repressor activity and virus assembly. The crystal structure of a mutant MS2 coat protein that is defective in viral assembly yet retains repressor activity has been determined at 2.0 A resolution. The unassembled dimer is stabilized by interdigitation of alpha-helices, and the formation of a 10-stranded antiparallel beta-sheet across the interface between monomers. The substitution of arginine for tryptophan at residue 82 results in the formation of two new inter-subunit hydrogen bonds that further stabilize the dimer. Residues that influence RNA recognition, identified by molecular genetics, were located across the beta-sheet. Two of these residues (Tyr85 and Asn87) are displaced in the unliganded dimer and are located in the same beta-strand as the Trp-->Arg mutation. When compared with the structure of the coat protein in the assembled virus, differences in orientation of residues 85 and 87 suggest conformational adjustment on binding RNA in the first step of viral assembly. The substitution at residue 82 may affect virus assembly by imposing conformational restriction on the loop that makes critical inter-subunit contacts in the capsid.
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7788290
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Thioredoxin--a fold for all reasons.
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The thioredoxin fold is a characteristic protein structural motif that has been found in five distinct classes of proteins that have the common property of interacting with cysteine-containing substrates.
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7788289
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Thioredoxin structure and mechanism: conformational changes on oxidation of the active-site sulfhydryls to a disulfide.
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The recent high-resolution solution structures of human and Escherichia coli thioredoxin in their oxidized and reduced states support a catalytic model of protein disulfide reduction involving binding of a target protein and nucleophilic attack by the active-site Cys32 thiolate to form a transition state mixed disulfide.
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7788288
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Annexins: a novel family of calcium- and membrane-binding proteins in search of a function.
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Although the annexins have been extensively studied and much detailed structural information is available, their in vivo function has yet to be established.
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7788281
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Pathology of the transmissible spongiform encephalopathies with special emphasis on ultrastructure.
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The transmissible spongiform encephalopathies are a group of genetic and infectious disorders which are exemplified by scrapie in animals and Creutzfeldt-Jakob disease in humans. The spongiform encephalopathies are characterized by symmetrical vacuolation of neurons and neuropil. Amyloid plaque formation similar to that found in Alzheimer's disease is conspicuous in many, but not all, of these diseases. The sub-cellular pathology features of the spongiform encephalopathies have been studied by conventional transmission electron microscopy, scanning electron microscopy, freeze fracture, negative staining and most recently by application of immunogold labelling methods. Although these studies have revealed many unusual structures, convincing virus-like particles have not been demonstrated. Considerable data, including important transgenic mouse studies, now suggest that a single cellular protein, designated prion protein, is necessary for infection. Ultrastructural immunogold studies have shown that prion protein is released from the surface of neurons and neurites, diffuses through the extracellular space around infected cells where it accumulates and finally becomes aggregated as amyloid fibrils. It is likely that the accumulation of prion protein within the extracellular space is instrumental in causing nerve cell dysfunction and, ultimately, neurological disease.
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7788280
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Electron microscopic studies on intracellular phage development--history and perspectives.
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This review is centered on the applications of thin sections to the study of intracellular precursors of bacteriophage heads. Results obtained with other preparation methods are included in so far as they are essential for the comprehension of the biological problems. This type of work was pioneered with phage T4, which contributed much to today's understanding of morphogenesis and form determination. The T4 story is rich in successes, but also in many fallacies. Due to its large size, T4 is obviously prone to preparation artefacts such as emptying, flattening and others. Many of these artefacts were first encountered in T4. Artefacts are mostly found in lysates, however, experience shows that they are not completely absent from thin sections. This can be explained by the fact that permeability changes induced by fixatives occur. The information gained from T4 was profitably used for the study of other phages. They are included in this review as far as electron microscopic studies played a major role in the elucidation of their morphogenetic pathways. Research on phage assembly pathways and form determination is a beautiful illustration for the power of the integrated approach which combines electron microscopy with biochemistry, genetics and biophysics. As a consequence, we did not restrict ourselves to the review of electron microscopic work but tried to integrate pertinent data which contribute to the understanding of the molecular mechanisms acting in determining the form of supramolecular structures.
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7788266
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Natural filling cystometry in infants and children.
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To evaluate natural filling cystometry in infants and young children. The study group comprised 37 infants and young children (mean age, 4.1 years) with various urological conditions. Suprapubic catheters were used in all patients with urethral sensation. Natural filling urodynamic (NFU) studies were performed using an ambulatory recorder and with an observer present throughout. For comparison, 17 of the 37 patients also had slow filling conventional cystometry (CMG). All NFU studies were successfully completed and the great majority of patients were unaffected by the investigation procedures. In comparison with conventional cystometry there were significant differences. For NFU, there was a lower bladder capacity (means, NFU 122 mL vs CMG 188 mL, P < 0.03); lower pressure rise on filling (means, NFU 5.7 cmH2O vs CMG 16.1 cmH2O, P < 0.001) and higher maximum detrusor pressures during micturition (means, NFU 130 cmH2O vs CMG 78 cmH2O, P < 0.01). Voiding efficiency was also slightly greater with NFU compared with CMG. Detrusor instability was recorded in five patients only during NFU and in two other patients only during CMG. A natural filling cystometry method which incorporates an unobtrusive recording system is likely to be superior to conventional CMG for assessing bladder function in infants and children. This is because (i) bladder function is investigated in near to natural conditions, (ii) the patients are mostly unaffected by the investigation procedures, (iii) there are significant differences between NFU and CMG in the measurements obtained, indicating that CMG may give false indices of bladder function.
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7788267
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Endoscopic treatment of vesico-ureteric reflux and urinary incontinence: technical problems in the paediatric patient.
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Bovine collagen has been successfully used for the endoscopic treatment of urinary incontinence (UI) and vesico-ureteric reflux (VUR) in children for more than 8 years, although its long-term efficacy has sometimes been questioned. Its failure is generally ascribed either to technical difficulties or to instability of collagen at the site of the implant. To assess the efficacy of the procedure we evaluated the children treated at this hospital between 1990 and 1993. A total of 156 children, aged 5 months to 13 years, were treated for VUR. Over the same period, 25 patients aged between 2 and 14 years (nine with neuropathic bladder and 16 with exstrophy-epispadias complex who were still incontinent after bladder neck reconstruction) had periurethral or pericervical glutaraldehyde cross-linked bovine collagen injection for UI. Five more children with exstrophy-epispadias complex (aged 1-3 years) underwent periurethral collagen injection to stimulate bladder enhancement and allow subsequent bladder neck reconstruction. In children treated for VUR, a single injection proved successful in 72.2% of cases (127 ureters); a second collagen injection raised the success rate to 81%. Continence improved in all nine neuropathic bladders and in 10 of 16 children with exstrophy-epispadias complex treated for UI after bladder neck reconstruction. In four of the five exstrophy-epispadias complex patients who were treated to stimulate bladder enhancement, bladder capacity increased by 25%. Endoscopic treatment of VUR seems to be a valid alternative to open surgery, even though concerns remain about the long-term efficacy of collagen implantation. An important distinction should be made between early and late failure of the procedure. Early failure, which we define as persistence of reflux, is usually due to incorrect technique or technical difficulties. Late failure, or recurrence of reflux, which has previously been attributed to the biodegradability of collagen, seems to be due to the displacement of the injected collagen. Micturition itself or high bladder pressure (such as detrusor instability) could be responsible for the displacement of the injected collagen medially and distally, where it can no longer support the submucosal ureteric tunnel. In the treatment of urinary incontinence, both the implant technique and the choice of the site of injection seem to have a considerable effect on the results. In our experience, endoscopic collagen injection is effective in the treatment of both urinary incontinence and VUR in paediatric patients. Accurate selection of patients and technical adjustments and refinements are essential to obtain the best results.
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7788268
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Delayed management of posterior urethral disruption in children.
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To review the results of delayed operative treatment of total disruption of the posterior urethra in children. Twelve boys (3-12 years, mean 7.5) with a suprapubic catheter were referred after primary management in other hospitals. All but one had been involved in road traffic accidents. In addition to their urethral injury, they all had pelvic fractures and the majority also had other major associated injuries. Six to 14 months after injury, abdominoperineal transpubic urethroplasty was performed in 11 patients according to Turner-Warwick. In one case a perineal anastomotic urethroplasty was performed. After the operation, voiding cysto-urethrography showed a wide anastomosis in all cases. After 3 to 45 months follow-up, there were no strictures. Eight boys were continent, two were totally incontinent, two had stress incontinence and one nocturnal enuresis. All patients with confirmed erections after injury also had erections after their operation. Primary suprapubic cystostomy and delayed repair can be used successfully for the treatment of posterior urethral disruption in children.
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7788265
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'Congenital' hydronephrosis: limitations of diagnosis by fetal ultrasonography.
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To determine whether children presenting clinically with pelvi-ureteric junction obstruction had fetal hydronephrosis. Forty-three children, born during or after 1985, presented clinically with pelvi-ureteric junction obstruction. Records of the maternal pregnancies were reviewed with reference to the findings of any fetal ultrasonography. In 25 patients fetal ultrasonography was performed at or beyond 30 weeks' gestation (mean 33.2). None had significant fetal hydronephrosis. Hydronephrosis due to pelvi-ureteric obstruction is not necessarily congenital and patients presenting clinically may differ inherently from those detected fetally.
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7788264
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Laparoscopic varicocelectomy: technique and results.
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To determine the safety and efficacy of laparoscopic varicocelectomy in the treatment of symptomatic varicocele. Indications for surgery were subfertility in 98 patients and pain in nine. All varicoceles were confirmed on Doppler ultrasound. Seventy-two per cent of the patients had left-sided varicoceles and bilateral varicoceles were seen in 27%. A three-puncture technique was used with carbon dioxide insufflation. The spermatic vessels were individually identified and clips were used to ligate the veins. The spermatic artery was preserved in all cases. The operation was performed on a day surgery basis with an average operative time of 61.4 min (56.6 min for unilateral and 75.8 min for bilateral varicocelectomy). Morbidity was low, with pneumoscrotum in two patients and wound infection in two others. Sixty-one patients for whom pre- and post-operative seminal analyses were available showed improvement in sperm count and motility, with a concomitant fall in the percentage of abnormal sperm forms. Laparoscopic varicocelectomy is safe and effective, causing minimal discomfort and allowing patients an early return to activity.
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7788263
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Nitric oxide and cyclic GMP formation following relaxant nerve stimulation in isolated human corpus cavernosum.
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To investigate further the role of the nitric oxide (NO)-cyclic GMP pathway as the mediator of relaxant neurotransmission in human corpus cavernosum and to establish whether impaired activity of this pathway contributes to the pathophysiology of impotence. Samples of cavernosal tissue were obtained from 59 men undergoing penile operations. The controls comprised four men with penile carcinoma and 17 with Peyronie's disease. Of the impotent men, 35 had clinical evidence of penile vascular disease on pre-operative investigation, whilst three had non-vascular impotence. Each biopsy was divided into two strips which were then suspended under tension in organ bath chambers. The relaxant innervation of one strip of each pair was stimulated electrically whilst the other strip was left unstimulated. The formation of NO and cyclic GMP was calculated by comparing their respective tissue content in the stimulated and unstimulated strips. Overall, stimulation of the relaxant innervation produced significant increases in the tissue content of both NO and cyclic GMP. Incubation with an inhibitor of NO biosynthesis abolished the mechanical relaxant response and the formation of both NO and cyclic GMP. The magnitude of relaxant response and the formation of NO was diminished in tissue from men with vascular impotence compared to controls. The increase in cyclic GMP content was similar in both these groups. Relaxant response, NO formation and cyclic GMP formation in tissue from men with non-vascular impotence was similar to controls. This study provides further evidence that the NO-cyclic GMP pathway acts as the mediator of nerve-evoked smooth muscle relaxation in human corpus cavernosum. Diminished NO formation following relaxant nerve stimulation may account for impaired relaxant responses found in tissue from men with vascular impotence and may contribute to the cause of their erectile dysfunction.
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7788262
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Kinetic analysis of prostatic volume in patients with stage D prostatic cancer treated with LHRH analogues in relation to prognosis.
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To evaluate the clinical usefulness of the kinetic analysis of prostatic volume in the prognosis of patients with Stage D prostatic cancer treated using luteinizing hormone-releasing hormone (LHRH) analogues. The reduction of prostatic volume was monitored in 12 patients with Stage D prostatic cancer using transrectal ultrasonography (TRUS) after treatment with LHRH analogues. Data obtained from the kinetic analysis of prostatic volume were compared with the prognosis. All the patients having a reduction time, tau (derived from the kinetic analysis of prostatic volume change with time), of less than 41 days had neither clinical progression within 15 months nor death caused by prostatic cancer during the 5-year follow-up, while the disease-specific 5-year survival rate in patients having a tau of greater than 42 days was as low as 17%. The difference in both the progression and disease-specific survival between these groups was statistically significant (P < 0.05) despite the limited number of patients. In contrast, conventional prognostic parameters showed no significant predictability for prognosis with the exception of prostatic acid phosphatase, which correlated strongly with the occurrence of progression within 15 months. The kinetic analysis of the change of prostatic volume using TRUS shows promise in the prognosis of the patients with Stage D prostatic cancer.
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7788261
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Computerized analysis of transrectal ultrasonography images in the detection of prostate carcinoma.
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To report on the use of automated image analysis in the interpretation of transrectal ultrasonographic images of the prostate. During transrectal ultrasonography, images were recorded from biopsies performed in 127 patients. Subsequently in the image, the puncture place was marked and analysed. Analysis of the images was performed with the Automated Urologic Diagnostic Expert (AUDEX) system, consisting of a personal computer connected to the ultrasound machine. From the images collected, parameters can be calculated for image classification. The parameters obtained with this procedure were correlated with the histological result. Evaluation showed a sensitivity of 84.8% and specificity of 87.5%. The positive and negative predictive values, to predict prostate carcinoma, were 84.8% and 87.5%, respectively. Automated image analysis can help in the diagnosis of prostate carcinoma. In patients with non-palpable lesions or with poorly visualized tumours, image analysis is superior to the standard current diagnostic techniques.
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7788260
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Correlation of morphometry, nucleolar organizer regions, proliferating cell nuclear antigen and Ki67 antigen expression with grading and staging in urinary bladder carcinomas.
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To investigate the correlation of four different indicators of proliferation--mean nuclear area (MNA) morphometry, nucleolar organizer region (NOR) count, proliferating cell nuclear antigen (PCNA) and Ki67 antigen expression--in specimens of invasive and non-invasive urinary bladder carcinomas with the grading and staging of the tumour and to determine which indicator is most suitable for discriminating between non-invasive and invasive carcinomas. Biopsies of 58 urinary bladder carcinomas of different grade and stage (38 invasive, 20 non-invasive) and 11 carcinomata in situ were included in the study. Ten specimens of normal bladder mucosa served as controls. Analysis of indicators was performed on sequential serial paraffin sections of the same tissue, applying each test once to one of four serial sections. In comparison to normal bladder mucosa the values of the four indicators were significantly greater (P < 0.001) in all carcinomata in situ and in carcinomas. Values also increased from grade 1 to grade 3 carcinomas, but indicator values were similar for carcinomata in situ and grade 2 carcinomas. All indicators correlated with each other and allowed a significant discrimination between grade 1 and 2 or grade 2 and 3 carcinomas. Non-invasive carcinomas (Ta) showed a significantly lower proliferative activity (P < 0.001) than invasive carcinomas but there were overlapping values within the invasive carcinomas (T1,T2 and T3/4). MNA, NOR count, PCNA index and Ki67 index could be correlated with tumour grade, but not with stage, of transitional bladder carcinoma. Of the indicators studied the Ki67 antigen was the most useful in differentiating between invasive and non-invasive carcinomas. This could be of prognostic relevance, especially for the heterogeneous group of grade 2 carcinomas.
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7788259
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Is there a role for in vivo methylene blue staining in the prediction of bladder tumour recurrence?
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To assess the role of in vivo staining with intravesical methylene blue in predicting tumour recurrence. Thirty-nine patients (27 men and 12 women, age range 43-75 years) newly diagnosed with bladder tumours were prospectively studied and followed for a minimum of 2 years. Potential biopsy sites were identified by staining intravesically with a 1% methylene blue solution and compared with random biopsy sites. Biopsy directed by methylene blue staining detected carcinoma in situ more often than random biopsy. Rates of recurrence were similar in both stained and unstained groups. Methylene blue staining does not add significantly to the management of patients presenting with bladder tumours.
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7788258
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Numerical chromosome aberrations in bladder cancer detected by in situ hybridization.
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To investigate the relationship between interphase cytogenetics and the grade and stage of bladder cancer in patients with transitional cell carcinomas of the urinary bladder. By use of in situ hybridization with chromosome-specific DNA probes, the copy number of pericentromeric sequences on chromosomes 7, 10, 11, 17, 18, X and Y was detected within interphase nuclei in formalin-fixed and paraffin-embedded sections of the routinely processed bladder cancers from 20 patients. The percentage of hyperdiploid cells (three or more spots) was estimated using light microscopy. The percentage of hyperdiploid cells for chromosomes 7, 11 and 17 was highly correlated with increasing tumour grade (P < 0.01, Spearman rank correlation) or increasing pathological stage (P < 0.01). The percentage of hyperdiploid cells for chromosome Y was not correlated with either grade or stage (P > 0.05). As high tumour grade and stage are both indicative of more aggressive tumour behaviour and a worse prognosis, these findings suggest that the percentage of hyperdiploid cells, especially for chromosomes 7, 11 and 17, may be highly predictive of bladder tumour aggressiveness. These preliminary results suggest that measurement of numerical chromosome aberrations using in situ hybridization in bladder cancer may offer a new objective and quantitative assay of the biological potential of individual tumours.
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7788257
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Ploidy and Tn-antigen expression in the detection of transitional cell neoplasia in non-tumour-bearing patients.
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To study the effectiveness of combining DNA ploidy and the blood-group related membrane antigen Tn as bladder tumour markers which have been individually associated with high tumour grade and poor prognosis. In particular to (i) determine whether use of these two markers would improve tumour detection compared with either alone, particularly of high grade disease and (ii) determine whether intermediate rates of marker expression would occur in bladder cancer patients with no current tumour compared with those with a tumour and a control group with benign prostatic hypertrophy. A total of 102 patients undergoing cystoscopic monitoring for either benign prostatic hyperplasia (BPH) or for transitional cell carcinoma (TCC) at the Repatriation Hospital and Flinders Medical Centre were included in the study. The patients comprised three study groups, those with BPH (n = 37), with TCC but no tumour present (n = 38) and those with TCC and a tumour present at cystoscopy (n = 27). Exfoliated cells obtained from bladder washings at cystoscopy were double-labelled using a monoclonal antibody to the Tn antigen and a DNA stain, propidium iodide and examined by flow cytometry. Rates of marker expression in 27 patients with tumours were 30% for Tn antigen, 30% for aneuploidy and 48% for either marker. Marker expression was strongly associated with tumour grade, with no expression at grade 1, 38% (3/8) tumours at grade 2 and 90% (9/10) at grade 3. In patients with a history of bladder tumours but no current tumour, rates were intermediate (30%) compared with patients with current transitional cell carcinoma (42%) and control patients (19%). The use of Tn antigen combined with DNA flow cytometry can increase tumour detection, particularly of high grade, aggressive disease. Gradation of expression of these markers across patient groups at increasing risk of a tumour, with intermediate expression in patients with no current tumour, suggests that marker expression may be detecting a preneoplastic stage of the disease, which is not possible with cytology. Given two parallel disease processes for superficial papillary and for high grade disease with invasive potential, the expression of high grade tumour markers in cells from cystoscopically normal bladders may represent a pre-clinical stage of aggressive disease. The identification of patients at risk of invasive disease using combinations of tumour markers may offer advantages in clinical management, particularly when no tumour is present and therefore no histopathological assessment is made.
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7788255
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Trospium chloride versus oxybutynin: a randomized, double-blind, multicentre trial in the treatment of detrusor hyper-reflexia.
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To compare trospium chloride (TCl), a quaternary ammonium derivative with atropine-like effects and predominantly antispasmodic activity, with oxybutynin (Oxy) in terms of efficacy and adverse effects. In a randomized, double-blind, multicentre trial, 95 patients with spinal cord injuries and detrusor hyper-reflexia were studied. Treatment consisted of three doses per day over a 2 week period, with either Oxy (5 mg three times daily) or with TCl (20 mg twice daily) with an additional placebo at midday. The results were evaluated with regard to changes in objective (urodynamic) data and subjective symptoms as well as the incidence/severity of adverse effects. With both drugs there was a significant increase in maximum bladder capacity, a significant decrease in maximum voiding detrusor pressure and a significant increase in compliance and residual urine; there were no statistically significant differences between the treatment groups. The percentage of patients who reported severe dryness of the mouth was considerably lower (4%) in those receiving TCl 2 x 20 mg/day than in those receiving Oxy (23%) 3 x 5 mg/day. Withdrawal from treatment was also less frequent in those receiving TCl (6%) than in those receiving Oxy (16%). Trospium chloride and oxybutynin, judged in terms of objective urodynamic parameters, are of substantially equal value as parasympathetic antagonists. However, assessment of tolerance in terms of adverse drug effects showed that TCl had certain advantages.
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7788256
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Should Stamey colposuspension be our primary surgery for stress incontinence?
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To evaluate the outcome of the Stamey procedure for stress incontinence and to decide if it is an acceptable first-line option for the treatment of patients. Between June 1987 and March 1993 67 women had Stamey bladder neck suspension carried out for the treatment of stress incontinence. In September 1993 all patients received a detailed questionnaire to ascertain their present status. Immediately after surgery 70% of patients were dry and 15% were much improved. At 6 months 56% of patients were dry and 21% were much improved. More than 1 year following surgery, of 58 patients responding only 31% were dry and 28% were much improved. More than 5 years after surgery only 18% of the 28 women responding were dry. The factors which were significantly associated with failure were obesity (P < 0.005) and the number of pads used per day (P < 0.05). Previous surgery may also be an important factor. The Stamey vesical neck suspension has a good early success rate but the results in the longer term are not acceptable. This operation should not be used as a first-line treatment for stress incontinence and should be reserved for specific patient subgroups.
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7788254
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Different susceptibilities of lymphokine-activated killer cells (LAK cells) among primary and metastatic renal cell carcinoma derived from the same patient.
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To investigate the susceptibility of primary renal cell carcinoma (RCC) and metastatic RCC to lymphokine-activated killer (LAK) cells using three RCC cell lines derived from the primary and metastatic tumours in a male patient with advanced RCC. Three RCC cell lines (named HANKS) were derived from a 44-year-old man with advanced RCC. HANKS-Pr, HANKS-Lu and HANKS-LN were established from the primary lesion and the metastatic lung and lymph node lesions, respectively. The susceptibility of HANKS cell lines to 18 different LAK cells obtained from either patients with urological cancer or from healthy volunteers was studied. The three groups of LAK cells were divided as follows: (A) LAK cells from RCC patients (n = 6); (B) LAK cells from patients with transitional cell carcinoma (TCC)/prostatic carcinoma (CaP) (n = 4) and (C) healthy volunteers (n = 8). A 51Cr-releasing cytotoxic assay was used to determine susceptibility. The mean percentage lysis of the HANKS cell lines to the 18 allogenic LAK cells were 28.1% in HANKS-Pr, 20.2% in HANKS-Lu and 10.4% in HANKS-LN. The susceptibility of HANKS-LN to LAK cells was significantly lower than that of HANKS-Pr and HANKS-Lu in all three groups (P < 0.05). In contrast, the susceptibility of HANKS-Pr was significantly higher than HANKS-Lu in group A only (P < 0.01). This is the first report to describe the different susceptibilities of primary RCC and metastatic RCC derived from the same patient. HANKS-LN itself might be the least susceptible to LAK cells because it was not related to the source of LAK cells. Furthermore, RCC may affect the cytotoxicity of LAK cells to HANKS-Pr. These data indicate there are at least two different types of mechanisms leading to the different susceptibilities of HANKS cells to LAK cells.
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7788253
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Surgery of lung metastases in renal cell carcinoma.
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To examine the impact on survival of pulmonary resection in the treatment of renal cell carcinoma that has metastasized to the lung. From June 1986 to July 1991, 19 patients were submitted to synchronous or asynchronous lung metastasectomy. Histological examination confirmed the presence of lung metastases from renal cell carcinoma in 16 cases (six synchronous and 10 asynchronous with a mean disease-free interval of 23 months). In the other three cases, histological examination revealed tuberculomas, chondroid hamartoma and foci of anthracosis. To date, among the six patients with synchronous lung metastases, three have died, two are progressing and one has no evident disease after a mean survival of 24 months. Among the 10 patients who underwent surgical resection of metachronous lung metastases, one has died, three are progressing and six have no evident disease (mean survival time, 43 months). While the presence of synchronous lung metastases is an unfavourable prognostic factor even after surgical removal (five out of six patients died or are in progression shortly after metastasectomy), the results after surgery of asynchronous lung metastases are encouraging, although the real efficacy of this treatment is still to be confirmed.
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7788252
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Involvement of the inferior vena cava by renal tumour: surgical excision using hypothermic circulatory arrest.
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To evaluate the immediate and long-term results of a radical surgical technique in the treatment of renal tumours with extensive involvement of the inferior vena cava (IVC). Seven patients with extensive involvement of renal tumours into the IVC were operated upon using a cardiopulmonary by-pass, hypothermia and cardiac arrest to facilitate surgery. Wide exposure of the IVC in a bloodless field permitted complete removal of all visible tumour in each case. Histological sections confirmed renal cell cancer in six patients and Wilms tumour in a 15-year-old girl. All patients recovered well from their surgery with no major complications and spent one or two days in the Intensive Treatment Unit and an average of 13 days in hospital after the operation. Of the seven patients, four are alive and well with no obvious disease after an average follow-up time of 30 months (range 8-54). The other three patients have died from disseminated renal cancer. This procedure provides good local control of the tumour and offers the only hope of cure in patients with this disease. In collaboration with the surgical cardiac team it can be safely carried out with acceptable morbidity and mortality.
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7788251
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Extracorporeal piezoelectric shock wave lithotripsy as mono and multiple therapy of large renal calculi including staghorn stones in unanaesthetized patients under semi-ambulant conditions.
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To examine the effectiveness and complication rate of extracorporeal piezoelectric shock wave lithotripsy (EPL) as monotherapy for the treatment of large renal calculi. Treatment consisted of semiambulant EPL as monotherapy combined with protective ureteric stenting in 84 patients. Three groups were established according to stone volume (borderline-stone, partial and complete staghorn). An average of 18,230 shock waves was applied in 3.76 sessions to each patient. No major complications were observed but there were minor complications in 33% of patients. Invasive auxiliary methods were necessary in only 12%. After a mean follow-up of 9 months (n = 72), 54% of patients were stone-free and in 22% the fragments passed spontaneously. Thus the success rate was 76%. Analysis of the three groups showed no difference in stone status during follow-up. There was no relation between the outcome of treatment and stone volume. Analysis of the patients who failed to respond to treatment showed that they were treated for longer than the stone-free group, with significantly fewer sessions per week (0.71 vs 1.28 sessions/week). It appears that higher rates of stone removal can be achieved with more frequent treatment sessions at shorter intervals. We consider semi-ambulant EPL monotherapy to be a minimally invasive alternative treatment in patients with large renal calculi, including staghorn stones.
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7788250
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Nocturnal enuresis.
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Nocturnal enuresis is common. Although its aetiology remains unclear recent evidence increasingly supports the lack of a normal nocturnal increase in ADH leading to nocturnal polyuria exceeding functional bladder capacity. Sleep patterns are probably normal although an arousal disorder might be a factor. Treatment should follow careful evaluation to determine if one is dealing with 'uncomplicated' or 'complicated' enuresis. Complicated enuresis requires further investigation. 'Uncomplicated enuresis' always requires reassurance and patient and parent education. Resource centres such as ERIC can provide information and advice. Active treatment should be tailored to the patients age, motivation and parental wishes. Behavioural modification techniques yield the highest long-term cure rate but require the most commitment and are rarely successful before the age of 7-8 years. Pharmacotherapy has been revolutionized by DDAVP which gives a response rate of up to 70% relatively free from side-effects but at the price of a high relapse rate after medication. Imipramine is less expensive than DDAVP but may be fatal in overdose. Anticholinergics should be reserved for those patients with significant diurnal symptoms or those who fail first-line pharmacotherapy. Overall patients and parents should be reassured by the high spontaneous cure rate.
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7788245
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Case report: variable imaging appearances of angiomyolipomas of the liver.
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Angiomyolipomas of the liver are rare benign tumours. We describe the variable imaging appearances of these tumours in three women. The first two patients underwent ultrasound, computed tomography (CT) and angiography, which demonstrated lesions resembling focal nodular hyperplasia and hepatocellular carcinoma, respectively. Both had histologically-proven liver angiomyolipomas surgically resected. The third patient was incidentally found to have typical features of multicomponented liver angiomyolipoma on CT. Variable proportions of fatty tissue in these tumours are the most likely explanation for their different imaging appearances on CT.
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7788243
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Case report: septic arthritis of the hip following ureteric stent insertion.
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Urinary infection is a recognized complication of ureteric stent insertion. We present a case of pelvic abscess and avascular necrosis of the hip following insertion of a stent for ureteric obstruction.
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7788242
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Case report: computed tomography in the investigation of bilateral mandibular coronoid hyperplasia.
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Bilateral mandibular coronoid hyperplasia is characterized by restricted mouth opening due to impingement of the coronoid processes on the zygomatic arches. The condition is unfamiliar to many clinicians and may be significantly under-reported. The presented case highlights the benefits of computed tomography (CT) in the diagnosis and surgical evaluation of this disorder.
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7788241
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Technical note: digital radiographic pelvimetry--a novel, low dose, accurate technique.
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A technique is described for lateral pelvimetry which results in a lower radiation dose than that resulting from conventional film-screen pelvimetry and computed tomography (CT) pelvimetry. It uses digital radiographic imaging thereby closely matching conventional techniques yet additionally providing post-processing facilities including distance measurement and contrast adjustment. The digital technique was evaluated with an anthropomorphic phantom and compared with the conventional technique by measuring entrance surface doses on two groups of post-natal patients. Digital radiography gave radiation doses 10 times lower than those using conventional techniques.
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7788240
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Technical note: a radiological education system--organization of an image library.
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A successful radiological library and teaching system should be easy to compile, user-friendly, dynamic and flexible. Nowadays it must be amenable to incorporation into digitally-based communication systems such as personal computers (pc) and picture archiving and communication systems (PACS). This article describes the structural organization and capabilities of such a digital radiological education system, and demonstrates how it fulfils these aims.
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7788239
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Technical note: maxillofacial biomodelling--preliminary result.
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A new technique of manufacturing three-dimensional (3D) hard tissue biomodels is described. The models, derived from computed tomography data, were constructed by a computer-controlled manufacturing device known as stereolithography apparatus (SLA). Selected cases of patients with facial deformities were presented to illustrate clinical applications of the SLA biomodelling. Physical demonstration of the bony internal anatomy in these patients promoted better conceptualization of the disease process, allowing optimal input into the management decision, pre-operative planning and choice of surgical technique with a consequent reduction in operating time and potential reduction in peri-operative morbidity. Limitations of the solid modelling technique include cost, a lengthy production time which renders it unsuitable for emergency cases, and radiation exposure of the patient. With wider use and further technological development, these drawbacks will be minimized. The 3D SLA biomodels may in future become an adjunct, not only to maxillofacial surgery, but also to other medical specialties.
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7788238
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Technical note: compression stockings and posture: a comparative study of their effects on the proximal deep veins of the leg at rest.
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Graduated compression stockings have been shown to reduce the incidence of deep venous thrombosis. While they are thought to act primarily by increasing venous flow velocity, their mode of action remains uncertain. Doppler ultrasound was employed to study the relative effects of three types of support stocking on the deep venous diameter, flow velocity and pulsatility in 10 non-pregnant female subjects. In addition, the effect of altered posture on the same parameters was assessed. Significant effects of the graduated stockings were found at the level of the popliteal vein, where a reduction in both the diameter and the amplitude of respiratory phasicity was recorded (p < 0.05). No significant increase in flow velocities was recorded. Adopting the left lateral position significantly increased flow velocity in the right common femoral vein (p < 0.05). The application of stockings in this position produced no additional increase in flow velocities, but did alter the amplitude of respiratory phasicity. These data do not support the widely held view that graduated compression stockings increase flow velocities at rest. Adopting a lateral recumbent position significantly increases flow velocity in the non-dependent leg.
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7788237
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Analysis of patient doses for myelogram and discogram examinations and their reduction through changes in equipment set-up.
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Patient doses for myelogram and discogram examinations performed on two C-arm X-ray units have been measured using dose-area product meters. Contributions to the dose from fluoroscopy and radiography have been obtained from analysis of results for a selection of examinations. Information was recorded about the individual beam projections used, in order to allow estimates of effective dose. Effective doses for lumbar myelograms were 3-4 mSv and for cervical myelograms and discograms were 1 mSv. The doses on the two units were similar, but contributions from the various parts of the examinations were different. Quality assurance (QA) measurements of dose variables were used to determine reasons for these differences in performance. Fluoroscopic doses are influenced by image intensifier dose rate and by the way in which exposure factor selection has been set up for the automatic exposure control (AEC) system. Doses from digital fluorography on units for specialized applications may be greater than those with standard film/screen systems. Recommendations have been made concerning ways in which doses on each unit might be reduced. Detailed assessments of doses resulting from AEC set-up options, made during QA tests, can help to ensure that the optimum balance between patient dose and image quality is achieved.
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7788236
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Assessment of organ radiation doses and associated risk for digital bifemoral arteriography.
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An assessment has been made of the absorbed dose associated with femoral arteriography using a digital imaging system. A bilateral femoral arteriogram was performed on 17 patients, using a filmless 1024 matrix digital image acquisition system with a discrete stepping tube-stand and 40 cm image intensifier. A standardized protocol of manual patient/tube-stand positioning under fluoroscopic control and automatic stepping digital acquisition was followed. Skin entry doses were measured with a dose-area product meter for each stage of the procedure, and the total gonad dose was assessed with thermoluminescent dosimeters (TLDs). Published Monte Carlo simulations were supplemented with further calculations to evaluate organ doses from the dose-area products measured. Comparison with the TLD measurements indicated that this technique over-estimated organ doses by about 30%. A mean effective dose of 3.1 +/- 1.8 mSv was calculated for the procedure, with the greatest dose burden being imposed by fluoroscopy during catheter manipulation. The related radiation detriment is 0.018%, which is insignificant when compared with the overall mortality from peripheral vascular disease.
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7788235
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Patient and staff dosimetry in neuroradiological procedures.
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Cerebral angiography provides valuable information for use in the clinical management of patients but can result in relatively high radiation doses to patients and staff due to the extended fluoroscopy time and number of images acquired during an examination. In this study, extremity doses to radiologists and scrub nurses working in a neuroradiological centre were monitored during a 3 month period using thermoluminescent dosemeters (TLDs). Electronic personal dosemeters were also used to monitor doses above the lead apron at chest height to the radiologists, radiographers and the scrub nurses. Patient doses were recorded using a dose-area product meter whilst patient thyroid dose was measured using TLDs. Two types of examination were studied: cerebral angiography and arterial embolization. It was deduced from the results of the study that the radiologist may expect to receive a mean dose above the lead apron at chest height of 11 microSv and 25 microSv per examination when performing cerebral angiography and arterial embolization, respectively. A radiologist mean hand dose of 19.3 microSv per examination was found, whilst the average eye dose for both radiologist and scrub nurse was 13.4 microSv per examination. The patient dosimetry results revealed a mean thyroid dose of 1.7 mSv and a dose-area product of 48.5 Gy cm2 for cerebral angiography. Average dose-area product for arterial embolization was 122.2 Gy cm2 along with a mean patient thyroid dose of 3.3 mSv. More detailed patient dosimetry was also performed using a Rando anthropomorphic phantom loaded with TLDs to measure organ doses and hence estimate effective dose. A typical four vessel angiogram was found to result in a patient effective dose of 3.6 mSv.
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7788233
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Dosimetric considerations in 131I-MIBG therapy for neuroblastoma in children.
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Dosimetric calculations have been made for organ doses in patients receiving 131I-MIBG therapy as treatment for neuroblastoma. As well as whole body and liver dose, consideration has been given to dosimetry of organs (lung, urinary bladder) whose tolerance may become treatment limiting when 131I-MIBG is given as part of combined modality therapy. Data from both adults and children receiving radiolabelled MIBG for diagnostic or therapeutic purposes have been compared in constructing dosimetry models for children. A recently published urodynamic model has been used in the estimation of radiation dose to the bladder. The results show that liver and lung may receive doses greater than the average total body dose (0.58 mGy MBq-1 and 0.35 mGy MBq-1, respectively, as compared with 0.25 mGy MBq-1 to the whole body). The organ dose estimates do not differ greatly from previous analyses except in the case of the bladder for which the new modelling studies have resulted in lower dose estimates (0.76 mGy MBq-1 administered, for dose to bladder surface from bladder contents) than in some published series. This may result from differing assumptions regarding parameters such as bladder content and urine flow rate, an enhanced fluid intake being assumed in the present bladder dose estimates. Average doses to the bladder wall from the contents were estimated to be 7.4-11.3% of the surface doses. The urodynamic modelling analysis shows that the bladder could receive a much greater dose (by an order of magnitude) in patients who were inadequately hydrated or had impaired renal function.
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7788234
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Entrance doses during lateral lumbar spine and antero-posterior abdomen examinations: generator waveform dependence.
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In North Trent, UK, an entrance dose survey of lateral lumbar spine and antero-posterior (AP) abdomen examinations has been carried out in 17 radiology departments. The survey comprised 294 lateral lumbar spine and 322 AP abdomen entrance dose measurements. The mean entrance doses were found to be approximately half of the relevant national reference entrance dose levels of 30 mGy and 10 mGy, respectively. The effect of generator waveform on entrance dose was studied by separating the generators into two types: "pulsating potential" (PP) generators and "constant potential" (CP) generators for each examination. PP generators comprised 23% of the total number of examinations. The mean entrance dose and radiographic exposure factors from CP generators were found to be significantly lower than those from PP generators. The use of CP type generators, together with low attenuation components can significantly reduce patient entrance doses for these examinations.
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7788232
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Ultrasound in the evaluation of osteoporosis: a comparison with bone mineral density at distal radius.
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It is proven that, from a technical point of view, ultrasound transmission velocity (UTV) measurement can easily be taken at the distal end of the radius. The reproducibility of UTV is good (coefficient of variation 0.3% intraoperator and 0.5% interoperator). 248 normal and 65 osteoporotic women were then studied to establish the range of UTV values and to compare the ability of UTV and bone mineral density (BMD) measurement, taken at the same skeletal sites, to detect osteoporotic fragility. Osteoporosis was defined by the presence of atraumatic vertebral fractures on an X-ray of the spine. Ultrasound velocity averaged 1570.5 +/- 43.3 m s-1 in normal and 1519.2 +/- 15.2 m s-1 in osteoporotic women; the difference is also statistically significant (p < 0.01) for BMD. Both BMD and UTV decline after menopause and are significantly correlated with age. A weak correlation (r = 0.68) was found between UTV and BMD; this supports the thesis that ultrasound velocity measures bone mass as well as other fragility components of bone distinct from the decrease of mass. Receiver operating characteristic (ROC) curve analysis showed that UTV discriminates between normal and osteoporotic patients at least as well as radial BMD, indicating that UTV is a new available diagnostic modality which can be used to screen osteoporotic subjects.
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7788231
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Measurement of human pancreatic perfusion using dynamic computed tomography with perfusion imaging.
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Absolute quantification of pancreatic perfusion in man has been extremely difficult to date. This paper describes a relatively simple application of dynamic computed tomography to provide perfusion imaging of the human pancreas. Values for perfusion in eight normal pancreases ranged between 1.25 and 1.66 ml min-1 ml-1 (mean: 1.52 ml min-1 ml-1). Increased perfusion values were present in a patient with an islet cell tumour (overall perfusion 2.11 ml min-1 ml-1) and a patient with Wilson's disease (3.43 ml min-1 ml-1). Pancreatic perfusion was reduced in a patient with diabetes (0.60 ml min-1 ml-1) and in a failing pancreatic transplant (0.97 ml min-1 ml-1). The combination of functional information and good spatial detail afforded by computed tomography (CT) perfusion imaging means the technique is well suited for the evaluation of the human pancreas. It is currently the only technique which allows non-invasive absolute quantification of pancreatic perfusion.
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7788230
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Magnetic resonance imaging in the detection of focal liver lesions: comparison of dynamic contrast-enhanced TurboFLASH and T2 weighted spin echo images.
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In a previous study using dynamic contrast-enhanced TurboFLASH (DCETF) for demonstration of the portal venous system we found that this technique showed more liver lesions than T2 weighted spin echo (T2WSE) imaging in the same patients. In this study we have formally compared axial T2WSE images (TR 2000, TE 45/90) with TurboFLASH images (TR 135, TE 4, FA 80 degrees) acquired immediately after bolus injection of Gd-DTPA (0.1 mmol kg-1) in 41 patients referred for hepatic magnetic resonance imaging (MRI) prior to surgery for liver lesions. The images of each sequence were independently reviewed by two observers. The lesions were counted and each sequence was scored for conspicuity, level of artefact and subjective image quality. Contrast-to-noise ratios using user defined regions of interest were calculated. Significantly more lesions were seen on DCETF (n = 186) images than on T2WSE (n = 123) images (p < 0.001). Lesion conspicuity was equal in 53% of cases, better on DCETF in 36% and better on T2WSE in 11%. Contrast-to-noise ratios were significantly higher on DCETF images (p < 0.05). DCETF imaging provided a substantial improvement in lesion detection compared with T2WSE imaging.
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7788229
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Prediction of gall stone composition by ultrasound: implications for non-surgical therapy.
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Oral cholecystography is the basic radiodiagnostic procedure required to assess chemical composition of gallstones as well as functional status of gall bladder prior to non-surgical management of gallstones. However, the value of ultrasound in non-surgical management of gallstones is yet to be proved. In this study we attempt to establish sonographic criteria which will predict the composition of gallstones prior to their non-surgical treatment. For this purpose the ultrasonographic characteristics of 233 patients with gallstone disease and functioning gall bladders were studied and an effort was made to correlate cholesterol and calcium content of different types of stones (as estimated by X-Ray powder diffraction study and atomic absorption spectrophotometry) with their ultrasonographic characteristics. Sonographic criteria for the presence of cholesterol stones were those which were floating and gallstones producing acoustic shadowing without internal echoes from within the stone. In detecting findings which would predict the presence of cholesterol stones on ultrasound, ultrasound had a sensitivity of 72.90% and a specificity of 100%. The predictive values of positive findings and negative findings were 100% and 93.4%, respectively. The demonstration of typical features of cholesterol stones on ultrasound obviates the need for oral cholecystography.
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7788228
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Ultrasound of the Achilles tendon after surgical repair: morphology and function.
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Ultrasound is a well established method for the examination of the Achilles tendon. The objective of the study was to provide answers to the following questions: What ultrasonographic structural changes are long lasting after surgical repair? How important is ultrasound with regards to the functional evaluation of late results? 60 patients were examined at an average 11 years (2-19) after surgical repair of Achilles tendon rupture. In only four patients sonographic morphology of the tendon was according to the non-injured side. A variety of distinct basic alterations in ultrasound morphology was found: a hypoechogenic ribbon ventrally to the dorsal paratenon (n = 40), spots of hypoechogenic areas in the tendon (n = 18), dishomogeneous hyperechogenicity with preservation (n = 12) or dissolving (n = 22) of its fibrillar components along the longitudinal axis. In most of the cases the paratenon was thickened or could not be differentiated. In the dynamic ultrasound examination gliding mechanism of the achilles tendon was limited in 41 patients. Extensive functional subjective and objective parameters of all patients were evaluated in an Achilles tendon score. The results were rated as excellent (n = 18), good (n = 29), satisfactory (n = 12) and poor (n = 1). There was no statistical correlation between ultrasound morphology and clinical outcome. Therefore, it was concluded that ultrasound examination is able to reveal long-lasting alterations in echogenicity of the tendon but is only of limited value with regards to evaluation of the functional results after surgical repair.
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7788227
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Mammographic features of invasive lobular and invasive ductal carcinoma of the breast: a comparative analysis.
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The mammographic appearances of 86 invasive lobular carcinomas were compared with those of 86 invasive ductal carcinomas of no special type matched for age, size and stage. There was no significant difference in the frequency of a mammographic abnormality consistent with malignancy between the lobular carcinoma (90%) and ductal carcinoma (96%) groups. A spiculate mass was the commonest feature in both groups (69% and 63%, respectively). There were no differences in the imaging features of masses in the two groups. In the lobular carcinoma group any mammographic abnormality was more likely to be seen on only one view and calcifications were less frequently observed. Multiple lesions were more frequent in the ductal carcinoma group. However, although these differences appeared to reach statistical significance, as they were only apparent in a study with a large number of comparisons, it is unlikely that these differences are practically significant. Analysis of the lobular invasive group failed to demonstrate any significant differences in the imaging features of the classical and mixed sub-types, a spiculate mass being the most common single abnormality in both. No mammographic differences of practical use to distinguish invasive lobular from invasive ductal carcinoma of no special type were demonstrated.
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7788226
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Predicting local recurrence by correlating pre-operative mammographic findings with pathological risk factors in patients with breast cancer.
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The pre-operative mammograms for 231 patients undergoing conservation surgery for breast cancer between March 1988 and September 1992 were analysed for features that may predict the presence of pathological risk factors of local recurrence (residual microscopic disease, extensive intraduct carcinoma (EIC) and lymphatic/vascular invasion). Residual microscopic disease was detected in 40% of patients and was associated with a DY mammographic pattern (p = 0.03), casting calcification (p = 0.0002) and absence of mammographic nidus (p = 0.0006). Residual microscopic disease was found in 75-88.9% of patients when two of these preoperative mammographic features were present in combination. The mean lumpectomy diameter was significantly smaller for patients with DY compared to N1 mammographic pattern on Wolfe grade (p = 0.039). Both residual disease and Wolfe grade were related to age (p = 0.0032 and p < 0.0001). EIC was found in 22% of patients and was associated with casting (p < 0.0001) and non-casting (p = 0.04) calcification, absence of mammographic nidus (p < 0.0001) and stellate mammographic nidus (p = 0.02). No significant association was found between mammographic features and lymphatic/vascular invasion. Pre-operative mammographic features can predict patients likely to have residual microscopic disease or EIC following conservation surgery for breast cancer. These patients should be selected for wider primary excision.
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7788223
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Reproducibility of cardiorespiratory measurements during submaximal and maximal running in children.
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With the increased use of oxygen consumption measurements in clinical and sporting studies, measurement variability has become more important to both the paediatric clinician and the sports scientist. In this study we assessed the reproducibility of cardiorespiratory measurements during submaximal and maximal running in children. Ten healthy, physically active boys (mean(s.d.) age 10.7(0.71) years) performed two submaximal and two maximal running tests within a 4 week period. The submaximal protocol consisted of three 6 minute runs at 7.2, 8.0 and 8.8 km/h. Every attempt was made to minimize the sources of non-biological variability at each testing session. During submaximal exercise, oxygen consumption (VO2), heart rate (HR) and fractional utilization appeared to be the most reliable measures accounting for over two-thirds of the total variation (coefficients of reliability (CR) of 68%, 94% and 82% respectively). Ventilation (Ve) and respiratory exchange ratio (RER) proved to be only moderately reliable accounting for less than half of the total variation (CR 50% and 45% respectively). At maximal exercise, VO2, Ve and time to exhaustion were most reliable, accounting for approximately two-thirds of the total variation (CR 65%, 63% and 63% respectively). Within this test environment, a two visit submaximal assessment was capable of estimating VO2 with a standard error of +/- 1.25 ml/kg/min. Similarly, for maximal testing a two visit assessment estimated peak VO2 with a standard error of +/- 2.28 ml/kg/min. On the evidence of these results a two visit assessment for submaximal and maximal exercise testing seems adequate to estimate the stability of submaximal cardiorespiratory measures and peak VO2 in healthy, normally active boys.
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7788222
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Leucocyte and erythrocyte counts during a multi-stage cycling race ('the Milk Race').
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Venous blood samples were taken from eight competitors in mid-evening after a racing day, and in the early morning before the next day's race, three times during the course of the Milk Race, 1992. These were used to gather information about the changes in circulating leucocyte levels in response to the exceptionally high sustained daily workload required during a major multi-stage race. The primary objective was to provide knowledge of 'normal' values against which future clinical judgements of abnormality might be made in these unusual circumstances. During the race, estimated energy output was about 25 MJ (6000 kCal)/day. The mean total circulating leucocyte numbers (per litre of blood), and those of individual leucocyte classes (neutrophil, lymphocyte, monocyte, eosinophil and basophil) were all inside the normal range both in the morning and in the evening. Evening counts were, however, 30-50% higher than morning counts, for all classes except eosinophils. We conclude that individual clinical decisions about leucocyte levels can best be made using normal (sedentary man) values if a morning sample is taken.
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7788221
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Rating of perceived exertion and heart rate relative to ventilatory threshold in women.
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Forty women took part in a study designed to investigate self-selected exercise intensity relative to ventilatory threshold during circuit weight training (CWT) and exercise-to-music (ETM) sessions. Subjects were assigned to one of two groups which were beginners (B) or habitual exercisers (HE) on the basis of their exercise habits. All subjects first underwent a laboratory cycle ergometer test involving a continuous incremental exercise protocol from which ventilatory threshold (VT) was determined using piecewise linear regression analysis. This point was expressed in terms of heart rate (VTHR) and rating of perceived exertion (VTRPE). These points were then compared with those determined during exercise training sessions (TRAHR and TRARPE respectively). The results showed that mean(s.d.) TRARPE (13.5(1.1) was not significantly different to mean(s.d.) VTRPE (12.8(0.5); P > 0.05) but that mean(s.d.) VTHR (134.8(13.5) beats min-1) and TRAHR (154.9(12.0) beats min-1) were different (P < 0.05). Beginners trained at a significantly higher percentage above VTHR than habitual exercisers (118(3.1) versus 111(2.8)% P < 0.05). During CWT the mean(s.d.) TRAHR for beginners (143.2(7.6) beats min-1) was significantly lower than that for habitual exercisers (152.5(10.1) beats min-1; P < 0.05), but not different during ETM (P < 0.05). When these TRAHR values were expressed relative to an estimated maximum heart rate (EMHR) they represented 86.5% in ETM and 80.5% in CWT which were different (P < 0.05). These results suggest that regardless of habitual exercise level and training mode, these women selected a common intensity of effort that was compatible with the described RPE.
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7788220
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Validity of conventional anthropometric techniques for predicting body composition in healthy Chinese adults.
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There is little information on the application of generalized prediction equations to ethnic groups other than Europeans and groups of European descent. The purpose of this study was to crossvalidate conventional equations on a group of 56 Chinese adults. Body density was assessed by underwater weighing and also predicted by equations which use a combination of selected skinfolds-biceps, triceps, pectoral, subscapular, abdominal, suprailiac, thigh and calf. There were significant correlations (P < 0.01) between the various methods of predicting percentage fat. However, analysis of variance revealed significant differences (P < 0.01) between mean values. In the men, the Jackson and Pollock equation underestimated, and the Durnin and Womersley equation overestimated, the percentage fat predicted by underwater weighing. The best predictor site in this group was the medial calf skinfold (r = 0.81), which is not included in either equation. In the women, the best predictor sites were the triceps, suprailiac and thigh. As these sites are also used in the Jackson et al. equation, it is not surprising that there was no difference between the prediction of percentage fat by this equation and underwent weight. It is concluded that the Durnin and Womersley and Jackson and Pollock equations tend to overestimate and underestimate, respectively, the percentage fat in Chinese men. Alternative equations which use the calf skinfold may be more appropriate for this ethnic group. In Chinese women, there appears to be good agreement between Jackson and Pollock and hydrodensitometric estimations of percentage fat.
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7788219
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Implications of health and safety legislation for the professional sportsperson.
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There are a large number of injuries in most professional sports every year, and research interest has usually centred around the medical aspects of these injuries. However, health and safety legislation also applies to professional sport, and it is important, as with any other occupation, to understand the underlying causes of the incidents leading to the injuries and to take steps to minimize future injuries. The introduction of the Management of Health and Safety at Work Regulations 1992 formalized a risk assessment approach to health and safety issues; an approach that has always been implicit in the Health and Safety at Work etc. Act 1974. This review assesses how the relevant UK health and safety legislation impacts on the professional sportsperson.
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7788218
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The estimation of body density in rugby union football players.
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The general regression equation of Durnin and Womersley for estimating body density from skinfold thicknesses in young men, was examined by comparing the estimated density from this equation, with the measured density of a group of 45 rugby union players of similar age. Body density was measured by hydrostatic weighing with simultaneous measurement of residual volume. Additional measurements included stature, body mass and skinfold thicknesses at the biceps, triceps, subscapular and suprailiac sites. The estimated density was significantly different from the measured density (P < 0.001), equivalent to a mean overestimation of relative fat of approximately 4%. A new set of prediction equations for estimating density was formulated from linear regression using the logarithm of single and sums of skinfold thicknesses. Equations were derived from a validation sample (n = 22) and tested on a crossvalidation sample (n = 23). The standard error of the estimate (s.e.e.) of the equations ranged from 0.0058 to 0.0062 g ml-1. The derived equations were successfully crossvalidated. Differences between measured and estimated densities were not significant (P > 0.05), total errors ranging from 0.0067 to 0.0092 g ml-1. An exploratory assessment was also made of the effect of fatness and aerobic fitness on the prediction equations. The equations should be applied to players of similar age and playing ability, and for the purpose of identifying group characteristics. Application of the equations to individuals may give rise to errors of between -3.9% to +2.5% total body fat in two-thirds of cases.
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7788217
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The physiological demands of Gaelic football.
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Match-lay demands of Gaelic football and fitness profiles were assessed at club competitive level. English Gaelic football club championship players (n = 11) were assessed for anthropometry, leg strength and time to exhaustion on a treadmill run. A similar test battery was administered to a reference group of University competitive soccer players (n = 12). Heart rate was recorded during match-play using radio telemetry and blood lactate concentrations were determined at half-time and after full-time. No differences (p > 0.05) were observed between the Gaelic and soccer players in: body mass (70.7 +/- 10.3 vs 76.6 +/- 10.3 kg); height (176 +/- 5.9 vs 177.7 +/- 6.4 cm); leg to trunk ratio (0.53 +/- 0.01 vs 0.54 +/- 0.03); adiposity (12.2 +/- 2.1 vs 13.5 +/- 3.2% body fat); mean somatotype (2.8 - 4.3-2.0 vs 2.4-4.2-2.4); leg strength measures; and performance on the treadmill. The percentage muscle mass values were lower for the Gaelic players compared to the soccer players (41.9 +/- 5.4 vs 47.3 +/- 5.2%; p > 0.005). For the Gaelic and soccer players, respectively, mean heart rate recorded during each half of match-play were (157 +/- 10 and 158 +/- 12 beats/min) and (164 +/- 10 and 157 +/- 11 beats/min), whilst blood lactates measured at the end of each half, were (4.3 +/- 1 and 3.4 +/- 1.6 mmol/l) and (4.4 +/- 1.2 and 4.5 +/- 2.1 mmol/l). Gaelic footballers at English club championship level seem to exhibit similar fitness profiles, and are subject to broadly similar physiological demands as University-level competitive soccer players.
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7788216
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Personal health benefits of Masters athletics competition.
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Questionnaires (750 respondents, 44.4% response rate) examined the long-term health value of endurance exercise training in older age-classed competitors ('Masters Athletes', 551 men and 199 women) over a 7-year period (1985-1992). The majority had initially completed maximal exercise tests. The weekly time devoted to training, competition and exercise-related travel was 10 to 30 h, and the annual expenditure on clothing, equipment and entrance fees was typically in the range Canadian $500-1500. Despite their age (mean(s.d.) 58(10), current range 40-81 years), only 1.4% reported sustaining a non-fatal heart attack and 0.6% had required bypass surgery over the 7-year interval. The majority (90%) were very interested in good health; 76% considered themselves as less vulnerable to viral illnesses than their peers, and 68% regarded their quality of life as much better than that of their sedentary friends. The majority of former smokers had stopped smoking before they began training, but 37% indicated that exercise had helped them in smoking withdrawal. In keeping with their health-conscious attitude, 59% had regular medical check-ups, and 86% obeyed legislation requiring use of a seat-belt when driving. In contrast with many older people, 88% slept well or very well. Slightly over half of the sample (57%) had sustained some injury which had limited their training for one or more weeks over the 7-year study. Although participation in Masters competition appears to carry considerable health benefits, gains may in part reflect an overall healthy lifestyle.
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7788215
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Pain and pain tolerance in professional ballet dancers.
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Pain experience in sport had been the subject of increasing research in recent years. While sports professionals have generally been found to have higher pain thresholds than control subjects the reasons for this are not entirely clear. The present study seeks to investigate one possible explanatory factor, the importance of the popular image of the physical activity and of the self-image of its participants, by examining pain experience in professional ballet dancers. Like sports professionals, dancers were found to have higher pain and pain tolerance thresholds than age matched controls in the Cold Pressor Test. However, they also reported a more acute experience of the sensory aspects of the pain. Explanations of this apparent paradox are discussed both in terms of the neuroticism scores of the two groups and in terms of the dancers' greater experience of pain and its relationship with physical activity. The results illustrated the importance of using multidimensional measures of pain in this type of investigation.
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7788213
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Amino acid metabolism in tennis and its possible influence on the neuroendocrine system.
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To investigate amino acid metabolism during endurance exercise as well as its influence on plasma prolactin (PRL) we subjected eight nationally ranked tennis players (mean(s.d.) age 25.6(2.8) years, mean(s.d.) weight 83.9(5.7) kg, mean(s.d.) height 184.4(4.6) cm) to 4h of continuous tournament tennis. Venous and capillary blood samples were taken before and after the exercise. Amino acids were measured by HPLC-fluorescence detection as o-phthalaldehyde derivatives; nonesterified fatty acids (NEFA), ammonia, total protein, glucose insulin and PRL by enzymatic methods. Exercise caused a decline of branched-chain amino acids (BCAA) by 28(14)%. Elevation of NEFA resulted in a significant mean(s.d.) increase of free tryptophan (TRP) (9.7(2.6) [pmol/microliter] vs 17.8(6.4) [pmol/microliter]. The mean(s.d.) ratio of free TRP:BCAA increased by 165%(90) which favours entry of free TRP into the brain. However, PRL did not change significantly. We conclude that during long-lasting interval sports BCAA contribute as energy substrates. Alterations in competition of amino acids at the blood-brain barrier favour entry of free TRP into the brain. PRL changes cannot be explained by the increase in plasma level of free TRP or the ratio of free TRP:BCAA.
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7788211
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Prediction of endurance running performance for middle-aged and older runners.
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The purpose of this study was to develop regression equations that would sufficiently predict the endurance running performance (ERP) of middle-aged and older runners (n = 55, 43-79 years). Among many independent variables which were selected as possible predictors of the ERP, oxygen uptake corresponding to the lactate threshold (VO2@LT), or age was found to be the single best predictor. Some variables representing training habits correlated significantly but only moderately with the ERP. Linear multiple regression equations developed in this study were: V5km = 4.203 + 0.054X1 - 0.028X2 (r = 0.87) V5km = 4.436 + 0.045X1 - 0.033X2 + 0.005X3 (r = 0.89) V10km = 4.252 + 0.042X1 - 0.026X2 (r = 0.79) V10km = 4.371 + 0.037X1 - 0.031X2 + 0.005X3 (r = 0.82) VM = 3.207 + 0.048X1 - 0.022X2 (r = 0.91) VM = 3.707 + 0.038X1 - 0.031X2 + 0.005X3 (r = 0.93) where V5km, V10km and VM are the mean running velocity at 5 km, 10 km and marathon races, respectively, and X1 = VO2@LT (ml kg-1 min-1), X2 = age (year), and X3 = average running duration per workout (min). We suggest that the ERP of middle-aged and older runners can be predicted from a linear combination of VO2@LT and age or a combination of these variables plus average running duration per workout.
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7788212
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Monitoring altitude acclimatization--a case study of an élite woman athlete.
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A simple study monitoring altitude acclimatization, which is not intrusive to the athlete's training, is described. Particular attention is drawn to the change in production of lactate in response to steady state exercise, before and after altitude. The results suggest that a more thorough assessment of aerobic ability at altitude is required than that described in the British Association of Sports and Exercise Science (BASES) guidelines. It is also relevant to note that elevations in haemoglobin, promoted by altitude, can mask iron abnormalities. It is therefore recommended to assay for iron in addition to haemoglobin.
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7788210
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Do the competition rules of synchronized swimming encourage undesirable levels of hypoxia?
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Recent anecdotal reports that some synchronized swimmers have become dizzy or disorientated towards the end of their performance, and in the worst cases fainted underwater, have caused concern. However, the rules of synchronized swimming encourage slow performance of compulsory figures, and an analysis of the competition placings and duration of underwater sequences showed that the highest rankings were gained by slowly performed compulsory figures and free programmes containing a long underwater sequence. The combination of breath-holding and the vigorous exercise involved suggests that some of the symptoms complained of by the swimmers might be due to hypoxia. We therefore studied the alveolar gas tensions in nine members of the Great Britain National Squad immediately following the performance of set figures and the initial underwater sequence of their free routine in a swimming-bath. All were cyanosed after the underwater sequences of the free routine and reported being mildly confused. The mean(s.d.) alveolar PO2 at this stage was 5.07(1.1) KPa, while three girls had an alveolar PO2 below 4 KPa, the lowest being 3.67 KPa. These gas tensions suggest that potentially dangerous levels of hypoxia may develop during competitive synchronized swimming and that prolonged underwent sequences should not be encouraged.
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7788209
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Physical and physiological profiles of Malaysian dragon boat rowers.
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Maximal oxygen consumption (VO2max) and maximal workload attained (WLmax) were determined in 28 Malaysian dragon boat rowers who were exercised to exhaustion on an arm ergometer. Mean VO2max was 2.75 l min-1 at a mean WLmax of 195.5 W. Anaerobic endurance power of the arms, determined by cranking at 100 RPM at a workload of 400 W and the time taken to maintain the cadence until it fell to 75 RPM, was 34.9(+/- 2.3) s. Leg performance, as determined by standing long jump and vertical jump, was 140.0(+/- 4.5) kg m and 100.3(+/- 3.1) kg m s-1 respectively. Right hand grip strength was significantly (p < 0.001) greater than the left hand. Percentage body fat of the rowers was 11.8(+/- 0.6)%. These values represent the first measurements of their kind performed on dragon boat rowers in Malaysia.
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7788207
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Surgical stabilization of spondylolisthesis in a wrestler.
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Sporting activity in wrestlers operated on for spondylolisthesis is not well documented in the literature. We present the case of a wrestler with a grade I L5-S1 spondylolisthesis who was L4-S1 arthrodesed due to pain not relieved by conservative methods. One year after surgery he had returned to full wrestling activity, including competitions. Two years later, he continues to wrestle at the same level of competition.
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7788208
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Bungee running: a further report.
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Further to the report from Queen Mary's NHS Trust on bungee running affecting children, we present three cases of injury in adults. Two cases of injury presented to Noble's (Isle of Man) Hospital and one to Whiston Hospital, Merseyside. In all three cases, the competitors were trying to stretch the 'bungee' to grasp a pint of beer as a prize, much enthusiasm being shown by spectators. All injuries occurred when the competitors were catapulted backwards with some force.
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7788205
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[The history and present status of biotechnology in the Czech Republic].
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The paper outlines the historical milestones in the development of biotechnology in the Czech Republic in the fields of research, education and manufacture. The section dealing with the present state describes fundamental research carried out in the institutes of the Academy of Sciences of the Czech Republic and the universities and technical colleges, the institutes of applied research subsidized by the pertinent ministries as well as privatized institutes. The numbers of institutes and researchers before and after the political changes in 1989 are compared and the grant agencies for support of science and research are listed. The section dealing with biotechnological industry characterizes the firms manufacturing the products and devices for pharmacy, agriculture, food industry and ecology.
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7788199
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[Arytenoid subluxation following endotracheal intubation--a case report].
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A previously healthy 39-yr-old man was scheduled for exploratory laparotomy due to acute abdomen. There was no sign of difficult intubation. After induction of anesthesia with thiopental and succinylcholine, the trachea was easily intubated with a 7.0 mm cuffed endotracheal tube. Surgery for a ruptured appendix with 2 drainage tubes lasted for 75 min was uneventful. At the end of surgery, the endotracheal tube was removed without difficulty. On the 1st postoperative day, the patient developed stridor. The symptom persisted even after conservative treatment and removal of NG tube. On the 12th postoperative day, a telescopic videolarygoscopy revealed immobile right vocal cord with anterior and medial displacement to the right. Arytenoid cartilage was moderately edematous. A diagnosis of right arytenoid subluxation was then made. On the 17th postoperative day, a closed reduction of right arytenoid cartilage using direct laryngoscope was performed successively under general anesthesia. Eight weeks after the reduction, his voice and laryngoscopic findings were normal. There has been only 18 reports with 27 cases of this complication found in the literature. However, it is generally believed that it is not so unusual. The post-intubation syndromes, such as sore throat, dysphonia, odynophagia, difficulty in swallowing or breathing which persists beyond 5 days warrant ENT consultation. Abnormal mobility of vocal cord, edema over arytenoid area found by indirect laryngoscopy should suggest the complication. Further confirmation is then needed. Although the result of our case is good, the reduction should ideally be done within 24-48 h after the incidence to avoid unfavorable long-term sequelae.
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7788204
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Inhaled fenoterol pretreatment attenuates airway resistance response to endotracheal intubation.
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Endotracheal intubation may induce vagal mediated bronchoconstriction. As fenoterol possesses bronchodilation effects, we studied the efficacy of fenoterol pretreatment on the increased resistance of total respiratory system (Rrs) caused by reflex bronchoconstriction in endotracheal intubation. Fifty patients were randomly allocated into two groups; group A (n = 25) with fenoterol inhaled and group B (n = 25) with placebo inhaled 10 min before induction. Patients were induced with sodium thiopental and vecuronium and resistance was measured 2 and 5 min after intubation with a Bicore pulmonary function monitor. Suctioning of the airway was performed 1 min before each measurement. Patients were further categorized into four conditions by smoking history and the presence of sputum in the suctionings. Condition I included patients that were smokers with no sputum collected. Condition II had non-smokers with no sputum collected. Condition III had patients with sputum collected but with no smoking history and condition IV were patients who had sputum collected and had a smoking history. Patient who received fenoterol have significant lower total respiratory after intubation than those receiving placebo. There were no significant differences in post-intubation Rrs between smokers and non-smokers. Patients with sputum had the highest resistance after intubation with the placebo group. Heart rate and blood pressure were augmented in both groups. Fenoterol pretreatment produced lower post-intubation Rrs after intubation when compared with the placebo group suggesting of a protective effect in vagal mediated bronchoconstriction.
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7788202
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An urgent technique of applying high frequency jet ventilation in patients with extreme periglottic stenosis.
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Applying high frequency jet ventilation (HFJV) to patients with extreme periglottic stenosis (EPS) carries high risk of barotrauma or severe circulatory depression, since the stenotic airway will result in inadequate outflow tract obstructing the passage of the expired gas. We encountered with emergent obstruction of the outflow tract in 13 patients with EPS during HFJV in endolaryngeal microsurgery (ELM) procedures. The phenomenon of progressive gas trapping occurred within seconds in all patients. Barotrauma and disastrous circulatory depression would occur if we had not recognized them and then taken some measures immediately. We surmounted these potentially lethal events without interrupting the surgical procedures and found neither hypoxia nor barotrauma in all these patients. This may attribute to an urgent technique, i.e., intermittent disconnecting the jet conduit at the junction of the proximal end of the insufflation catheter and the distal end of the patient connecting tube of jet ventilator during HFJV.
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7788201
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[Complications of massive blood transfusion after intrathoracic hemorrhage--a case report].
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Acute hemorrhage leading to acute hypovolomic shock is a medical emergency carrying high mortality. It therefore requires prompt and effective treatment. We reported a case of lung tumor receiving lobectomy at our hospital. Repeated internal bleeding due to subclavian artery perforation occurred three times within three weeks after the surgery. During the period of resuscitation, the patient received emergently massive blood transfusion. Some complications of massive blood transfusion. Some complications of massive blood transfusion were noted later. A total of 89 units of whole blood, 34 units of fresh frozen plasma and 28 units of platelet was given.
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7788198
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Foley catheter used as bronchial blocker for one lung ventilation in a patient with tracheostomy--a case report.
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Anesthesia with one-lung ventilation is a good anesthetic technique for patients receiving thoracotomy in various underlying diseases. One lung ventilation can be achieved successfully by the application of a double-lumen endotracheal tube through the oral route. However, there are several situations such as low body weight, young age, difficult intubation, anatomic anomaly, and tamponading endobronchial bleeding in some adult patients, etc., in which lung separation by a double-lumen endotracheal tube may be relatively contraindicated because insertion is either difficult or dangerous. Bronchial blocker with a Fogarty embolectomy catheter has been used successfully for such situations. Here, we reported the clinical experience in using the Foley catheter as the bronchial blocker in a patient with tracheostomy.
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7788197
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Anesthesia for elective cardioversion: a comparison of thiopentone and propofol.
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Cardioversion is still a trend of therapy for cardiac dysrhythmias. With the application of new intravenous anesthetics, cardioversion can be performed safely and effectively with rapid onset of and quicker recovery from anesthesia. We compared the anesthetic effects of a new synthetic agent, propofol, with thiopentone which was mostly used in the past. Twenty four ASA class II to III adult patients scheduled for elective cardioversion in the coronary care unit were included in this study. All patients were given fentanyl (2 micrograms/kg, i.v.) three min before induction and were randomly assigned to receive either thiopentone 1.5 mg/kg (group 1) or propofol 1 mg/kg (group 2) for induction of anesthesia. Supplementary oxygenation was administered throughout. Both drugs could provide satisfactory anesthesia for elective cardioversion without major complications. Recovery time was shorter with propofol (p < 0.05). Comparing with previous reports, a higher incidence of apnea and prolonged sedation were noted in this study. This might be due to the additive effect of thiopentone or propofol with fentanyl. Both anesthetics were suitable for elective cardioversion with negligible side effects in hemodynamically stable patients.
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7788196
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[Clinical experience of laryngeal mask airway in lateral position during anesthesia].
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The laryngeal mask airway (LMA), inserted blindly into hypopharynx in patients in supine position, has been reported to be successful in the management of the airway and can provide adequate ventilation during anesthesia. In our study, we used LMA to maintain airway during anesthesia in patients in lateral position. Eighty surgical patients, ASA class I-II, undergoing hemorrhoidectomy, were placed in lateral surgical position before induction. The induction agents were propofol (2 mg/kg), fentanyl (2 micrograms/kg) and atracurium (0.5 mg/kg, i.v.). When mouth opening can be done passively, a LMA was inserted into the mouth and advanced blindly over the tongue into the pharynx until resistance was felt. The rim was immediately inflated with air and several manual positive pressure ventilatory breaths were given to the patient to check for leaks in the LMA system. Chest movement was observed and bilateral lung ausculation was performed to confirm the adequacy of ventilation. Once the LMA was in place, enflurane with oxygen was administered until operation was completed. During the anesthetic course, EKG, blood pressure, pulse oximeter, end-tidal CO2 and inspiratory pressure were monitored. Blind insertion of LMA in lateral position was successful in the first attempt in 70% (56/80) of patients. Twenty (18/80) patients required a second or third trial making the total successful rate of LMA insertion as high as 90% (74/80). In four patients, airway control through LMA was unsatisfactory due to large air leakage during manual ventilation. In two patients the LMA could not be inserted in proper position for maintaining airway. In six cases, the LMA was immediately removed and was substituted by face-mask for anesthesia. Two patients complained of postoperative sore throat. No other specific complications such as cough, laryngospasm and aspiration was noted. We demonstrated that LMA can be easily inserted and can provide effective patency of airway during anesthesia even in lateral position. It can be used as a substitute for face-mask in anesthesia in this position to prevent complications such as pressure injury that a face-mask may cause.
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7788195
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Prior epidural injection of 10 ml normal saline reduces the incidence of inadvertant venous puncture in epidural catheterization.
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Anesthetically, epidural neural blockade is widely used in the fields of surgery and obstetrics as well as in diagnosis and management of acute and chronic pain. However, inadvertent epidural venous puncture might be a serious problem, or even life-threatening particularly when drug is erronaneously injected and prompt diagnosis is not made correct and treatment is not instituted. Although many anesthesiologists suggested that injection of fluid into the epidural space before catheter insertion could prevent an epidural venous puncture, some others did not agree to it. This study aimed a assess the effect of injection of different volumes of saline into the epidural space before catheter insertion on the incidence of epidural venous puncture. Three hundred ASA I or II patients receiving Extracorporeal Shock Wave Lithotripsy (ESWL) were randomly divided into three groups: group A (no saline), group B (5 ml of saline) and group C (10 ml of saline). After the injection of different volume of saline into the epidural space, an epidural catheter was inserted into the epidural space via a Touhy needle. The incidence of epidural venous puncture in each group was compared. The incidence of epidural venous puncture in group A and B was 14% and 11%, respectively. However, the incidence in group C (1%) was significantly lower than the other two groups. Our results suggest that injection of 10 ml saline into the epidural space before catheter insertion could significantly diminish the incidence of epidural venous puncture.
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7788194
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Use of a single lumen endotracheal tube and continuous CO2 insufflation in transthoracic endoscopic sympathectomy.
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Transthoracic endoscopic sympathectomy (TES) is an accepted standard surgical treatment for palmar hyperhidrosis. For anesthetic management, a double lumen endobronchial tube is usually used to deflate the lung on the operative side. Recently we have applied continuous insufflation of carbon dioxide (CO2) into the pleural cavity to merely compress one lung while ventilating both lungs with a conventional single lumen endotracheal tube. We have studied 45 patients (ASA I and II) who underwent bilateral TES, Thirty-three were ventilated by single lumen tube and the other 12 by double lumen endobronchial tube with one lung ventilation. In both groups I and II, CO2 was insufflated slowly through the scope to a intrapleural pressure of 20 cm H2O. Both lungs were ventilated with peak pressure of less than 20 cmH2O at tidal volume of 5-12 ml/kg at 10-16 beats/min. In these patients, no CO2 retention was noted. Oxygenation and cardiovascular stability were maintained and there were no complications. In the double lumen series, we found that oxygen saturation was less uniform and less stable than those in the single lumen series. It is concluded that the use of single lumen endotracheal tube with continuous insufflation of CO2 in TES is easy, simple and safe.
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7788193
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[The thermoregulatory threshold during surgery with propofol-nitrous oxide anaesthesia].
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Thermoregulatory responses are thought to be drastically suppressed by general anesthesia. In previous studies, it was shown that halothane, isoflurane and fentanyl-N2O combination decrease the threshold of vasoconstriction in general anesthesia. Propofol is a recently introduced intravenous anesthetic. The thermoregulatory threshold of its administration during surgery has not been quantified. Fourteen unpremedicated ASA class I patients were anesthetized with N2O (67%) and propofol (2 mg/kg in bolus followed by 6 mg/kg/h infusion) during elective surgery of free flap. Patients were randomly assigned either to receive additional warming (n = 5) or standard (n = 9) management. Significant vasoconstriction was prospectively defined as the temperature gradient between forearm surface and finger-tip surface is > or = 4 degrees C, and the thermoregulatory threshold was defined as the esophageal temperature (core temperature) at a point where the skin temperature gradient between two tested zones exceeds 4 degrees C. Vasoconstriction did not occur in patients who received additional warming and they remained in nearly normothermia. The average minimum core temperature was 36.3 +/- 0.4 degrees C. In patients who underwent standard management the core temperature ranged from 32.8 to 34.6 degrees C (33.6 +/- 0.7 degrees C), signifying significant vasoconstriction. General anesthesia with propofol/N2O during surgery drastically inhibits thermoregulatory vasoconstriction. This effect should also be noted during long-term use of propofol (e.g. ICU-sedation).
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7788192
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The physiological effect of CO2 pneumoperitoneum in pediatric laparoscopy.
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The physiological effect of CO2 pneumoperitoneum during laparoscopy is a great concern of the anesthesiologists. Its effect in pediatric laparoscopy has not been previously reported. The purpose of this study was to examine the physiological alteration of pediatric patients during CO2 pneumoperitoneum. One hundred and twenty six children aged from 11 mon to 13 yr undergoing laparoscopic inguinal exploration were divided into three groups based on age orientation: group I comprising 40 children with age from 11 mon to 2 yr; group II 46 children with age between 2 to 5 yr; and group III 40 children aged from 5 to 13 yr. All patients received endotracheal anesthesia with halothane-N2O in 50% O2 and atracurium for muscle relaxation. Respiration was controlled by an Ohmeda 7000 ventilator with constant minute ventilation to maintain baseline end-tidal CO2 tension (PETCO2) between 32-33 mmHg. After anesthesia, CO2 was insufflated into the peritoneal cavity via the opened hernia sac. The intraabdominal pressure exerted by CO2 was 10 mmHg and the duration of pneumoperitoneum and laparoscopy was 15 min. We recorded airway pressure, PETCO2, body temperature, blood pressure, heart rate, heart rhythm, and oxygen saturation simultaneously at 1 min interval before, during, and after laparoscopy. The airway pressure and PETCO2 showed significant increases during laparoscopy (15-18% and 18-20% respectively) in all cases, but the percentage of increases were not significantly different among groups. However, the PETCO2 change in terms of time lag were different between groups: (1) the time lag from CO2 insufflation to the emergence of PETCO2 change (latent period) was respectively 0.7 +/- 0.1 (mean +/- SD) min in group I, 0.9 +/- 0.2 min in group II and 1.5 +/- 0.2 min in group III (p < 0.05); (2) the PETCO2 change from baseline to a plateau (ascending period) was respectively 4.2 +/- 0.6 min in group I, 6.3 +/- 1.0 min in group II and 9.1 +/- 1.1 min in group III (p < 0.05); (3) the PETCO2 decline from plateau to baseline after CO2 deflation (descending period) was respectively 6.2 +/- 0.5 min in group I, 8.3 +/- 0.8 min in group II and 12.0 +/- 1.3 min in group III (p < 0.05). The body temperature and hemodynamics including blood pressure, heart rate, heart rhythm, oxygen saturation were not significantly changed during laparoscopy in all groups. The changes of PETCO2 during laparoscopy did not influence the hemodynamic stability in our study. The younger children give a faster reaction time of PETCO2 change after CO2 insufflation than do the older children which may be related to the variation of physiological exhibition at different state of development.
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7788179
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The association between physical function and psychological problems in children with juvenile chronic arthritis.
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Twenty-nine children with juvenile chronic arthritis, aged from 7 to 16 yr were studied using the Juvenile Arthritis Functional Assessment Report for Children and Parents questionnaires (JAFAR-C and JAFAR-P). The results showed that JAFAR-C and JAFAR-P were highly correlated (P < 0.001) with each other and also with a predicted JAFAR score (P < 0.05). The JAFAR score correlated with the arthritic joint count at the time of the study (P < 0.01), Steinbrocker classification (P < 0.001), pain score (P < 0.01) and stiffness score (P < 0.005). Evidence of psychological dysfunction was found in eight of the 29 children (27%). Six children (21%) scored 13 or more on the Rutter A(2) for parents and one patient scored more than nine on the Rutter B(2) for teachers. Only one child had a score on the Birleson self-rating scale that was high enough to suggest a likely diagnosis of depression. The median Lipsitt self-concept scale score was 86, that expected for a healthy population. There was no correlation between the psychological scores and any of the other functional measurements, although the numbers affected were small. There was no significant difference between type of arthritis at onset with regard to any of the scores obtained.
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7788177
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Antinuclear antibodies in early onset pauciarticular juvenile chronic arthritis (JCA) are associated with HLA-DQB1*0603: a possible JCA-associated human leucocyte antigen haplotype.
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A panel of 43 early onset pauciarticular (EOPA) juvenile chronic arthritis (JCA) patients have been typed for human leucocyte antigens (HLA) DRB1, DPB1, DQA1 alleles, and DQB1*0603 status using molecular-based methods. Increased frequencies of DRB1*08 [odds ratio (OR) 7.7, 95% confidence interval (CI) 2.6-22.3], DRB1*11 (OR 3.1, 95% CI 1.2-8.1), DRB1*1301 (OR 7.7, 95% CI 2.6-22.3), DPB1*0201 (OR 3.5, 95% CI 1.6-8.0), DQA1*0103 (OR 4.4, 95% CI 1.5-13.3), DQA1*0501 (OR 2.9, 95% CI 1.3-6.6), DQA1*0601 (OR 30, 95% CI 3.6-241) and DQB1*0603 (OR 7.3, 95% CI 3.0-17.6) were found in the EOPA-JCA group compared with Caucasoid controls. Stratification of the EOPA-JCA group into antinuclear antibody (ANA) positive (n = 18) and ANA negative (n = 25) individuals revealed that ANA positivity was only associated with DRB1*1301 (OR 4.2, 95% CI 1.0-17.3), DPB1*0201 (OR 4.0, 95% CI 1.0-15.7) and DQB1*0603 (OR 11.5, 95% CI 2.5-53.4). Further analysis of the relative contributions of HLA antigens to ANA status revealed that DQB1*0603 determined the primary HLA effect. No apparent interaction between DQB1*0603 and DRB1*1301 or between DQB1*0603 and DPB1*0201 was found to contribute to the association with ANA. We suggest that those ANA positive individuals with a restricted HLA background, (DQB1*0603 positive), defines a group of EOPA-JCA patients which will be especially valuable in the characterization of the ANA associated with EOPA-JCA.
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7788178
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Increase of activated factor VIIA and haemostatic molecular markers in juvenile chronic arthritis.
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Activated factor VIIa (FVIIa), von Willebrand factor antigen (vWF:Ag), D-dimer and thrombin-antithrombin III complex (TAT) were measured to monitor coagulation status in patients with juvenile chronic arthritis (JCA). Subjects included 14 patients with systemic JCA, 16 with pauciarticular JCA and 16 with polyarticular JCA without disseminated intravascular coagulopathy, thrombosis or liver dysfunction. All types of JCA showed an increase of FVIIa, D-dimer and TAT, indicating enhanced activation of coagulation. In systemic JCA only there was also characteristically an elevation of vWF:Ag. We conclude that all types of JCA constitute a state of subclinical hypercoagulopathy caused by tissue damage and that additionally systemic JCA involves a prothrombotic state associated with or precipitated by vasculitis.
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7788176
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Inflammatory cytokine responses in juvenile chronic arthritis.
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The inflammatory cytokines interleukin 1 beta (IL-1 beta) interleukin 6 (IL-6), tumour necrosis factor alpha (TNF alpha) and the anti-inflammatory peptide--the interleukin 1 (IL-1) receptor antagonist--were measured in the plasma of children with juvenile chronic arthritis (JCA). In the two subgroups studied (polyarticular JCA and systemic JCA), there was good correlation between laboratory measures of disease activity C-reactive protein (CRP), erythrocyte sedimentation rate and clinical scores for disease activity. Despite higher levels of CRP in the systemic group IL-1 beta levels were lower and regression analysis recorded a difference in the relationship between CRP and IL-1 beta within the two clinical groups. In contrast, IL-6 levels were high in the systemic group and correlated with disease activity. No such correlation was observed in the polyarticular group. Five children with systemic JCA were studied during the febrile phase of their illness. IL-6 levels rose and fell with the fever. TNF alpha levels also rose and fell but out of phase with the fever. In contrast IL-1 beta levels were either undetectable throughout the febrile episode or only became detectable as the temperature reduced to normal. The IL-1 receptor antagonist was usually found in 1000-fold excess over IL-1 beta, levels rising and falling with the fever. These results demonstrate difference in the cytokine profiles and acute phase protein responses in polyarticular and systemic JCA. This would suggest different pathogenic mechanisms for these two groups of JCA with IL-6 being the more important cytokine in systemic JCA.
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7788175
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Intra-articular and soft tissue injections: a survey of current practice.
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Intra-articular and soft tissue injections are the two most frequently used procedures in rheumatological practice. A questionnaire completed by 172 consultant rheumatologists aimed to ascertain the techniques used in these procedures. The results showed a wide divergence of practice in almost every aspect of technique. Respondents were willing to undertake injections in almost any location, but differed widely regarding personal and patient preparation before injection. About one-quarter used no local anaesthetic, the majority using local anaesthetic before or with the corticosteroid. Admission overnight or as a day case for injection of weight-bearing joints was practised by 18%. Post-injection advice was extremely variable. The results suggest that there is at present no single consensus technique for intra-articular and soft tissue injections amongst British consultant rheumatologists.
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7788173
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Shoulder pain in a community-based rheumatology clinic.
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The objective of this study was to assess the prevalence of different shoulder disorders likely to be experienced by a rheumatologist in a community-based rheumatology clinic. We assessed patients with shoulder pain presenting to a large general practice at a community-based rheumatology clinic. It was found that the more common conditions seen were rotator cuff lesions (65%), pericapsular soft tissue pain (11%), acromioclavicular joint pain (10%) and referred pain from cervical spine (5%). In conclusion this study has established the spectrum of shoulder disorders referred from general practice to a highly accessible community-based rheumatology clinic. The diagnostic processes to distinguish the different conditions rely chiefly on an accurate history and directed examination.
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7788172
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Sulphasalazine-induced autoimmune abnormalities in patients with rheumatic disease.
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Sulphasalazine is a commonly used second line agent in rheumatoid arthritis (RA) and other inflammatory joint diseases and is reported to be one of the least toxic of this group of drugs. Recently a severe allergic reaction and cases of lupus-like disease have been described in patients with RA after treatment with sulphasalazine. We describe five patients, all with inflammatory arthropathy who developed cutaneous vasculitis, lupus-like disease or atypical serology after exposure to sulphasalazine. Three of four cases investigated were found to have the slow acetylator phenotype. These reactions can complicate the diagnosis and delay discontinuation of the drug. Moreover, present guidelines for the diagnosis of drug-induced lupus do not apply to the majority of patients with sulphasalazine-induced lupus.
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7788171
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Adult onset Still's disease in northern India: comparison with juvenile onset Still's disease.
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The present study compared the clinical and laboratory picture, the disease course and outcome in 31 patients having adult onset Still's disease (AOSD) with 23 patients having juvenile onset Still's disease (JOSD). The median age at disease onset was 20 and 7 yr for AOSD and JOSD patients, respectively. On analysing and comparing our data on these two groups, no significant differences emerged except that adults had a significantly lower time interval from disease onset to remission as compared to juveniles. Upon comparison of data on our AOSD patients with that published from abroad, rash, adenopathy and sore throat were less frequent. No clinical or laboratory variables were found to predict the subsequent disease course and outcome in either group. The functional outcome was good in about 70% of both groups and mortality was low. It is concluded that the clinical picture and outcome in AOSD is similar to that of JOSD.
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7788170
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Total and free methotrexate pharmacokinetics, with and without piroxicam, in rheumatoid arthritis patients.
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The pharmacokinetic profile of total and free methotrexate (MTX) and the effect of piroxicam on MTX pharmacokinetics was studied in 20 rheumatoid arthritis patients receiving a stable dosage of MTX (10 mg/week). Plasma protein binding ranged from 25 to 55%. To describe the variations with time of the unbound fractions a mathematical characterization relationship between the total and free MTX was used. Total and free MTX were correlated with the sigmoid maximum effect model. The slope factor (gamma) was proportional to the number of binding sites. The free fraction for a given patient can be evaluated from this relationship. Total clearance of MTX was not statistically different with piroxicam (8.0 l/h for total MTX, 13.7 l/h for free MTX) vs without piroxicam. Likewise, there were no significant difference in tmax, area under the plasma concentration vs time curve, distribution and elimination half-lives, mean resonance time, and volumes of distribution. Although the highest observed total MTX concentration was significantly lower with piroxicam, there were no significant pharmacokinetic interactions between low-dose MTX and piroxicam.
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7788169
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Antibodies to Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis in the sera of ankylosing spondylitis patients with/without iritis and enthesitis.
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IgM, IgG and IgA class serum antibodies against the whole Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis bacteria, as well as against K. pneumoniae and E. coli lipopolysaccharides (LPSs) were studied earlier in the sera of 98 patients with ankylosing spondylitis (AS) and in 102 healthy blood donors by enzyme immunoassay. In this study the patients were divided into groups according to the clinical picture, i.e. presence or absence of iritis and enthesitis. The previous major finding of increased IgA class antibody levels against the whole K. pneumoniae bacteria in AS patients when compared to the healthy controls was not specifically associated with any single patient group in the present study. However, the patients with iritis had higher levels of IgA class antibodies to LPS of K. pneumoniae and E. coli when compared to the patients without iritis. In addition, the patients without enthesitis had higher level of IgG class antibodies against whole K. pneumoniae bacteria compared to the patients with enthesitis. The increased IgA class antibody levels against K. pneumoniae and E. coli LPS in AS patients with iritis may reflect an inflammatory process in the gut area. Furthermore, there were certain other differences in the immunological parameters between the AS patients with and without iritis or enthesitis and the possibility that they reflect different mechanisms involved in the disease processes cannot be excluded.
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7788168
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Antibodies to Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis in the sera of patients with axial and peripheral form of ankylosing spondylitis.
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IgM, IgG and IgA class serum antibodies against the whole Klebsiella pneumoniae, Escherichia coli and Proteus mirabilis bacteria, as well as against K. pneumoniae and E. coli lipopolysaccharides (LPSs) were studied earlier in two separate patient populations of 99 and 85 patients with ankylosing spondylitis (AS) and in 102 healthy blood donors by enzyme immunoassay. In this study the patients were divided into groups according to the presence or absence of peripheral arthritis. The patients with peripheral type AS had increased levels of IgM and IgA class antibodies against K. pneumoniae, whereas the patients with axial type AS had increased levels of IgG and IgA class antibodies to K. pneumoniae, as well as IgA class antibodies against E. coli and P. mirabilis bacteria. Sulphasalazine treatment decreased the IgM and IgA class antibodies in peripheral AS and IgA class antibodies in axial AS against K. pneumoniae LPS. The antibody levels were also decreased against E. coli and P. mirabilis bacteria in the sera of patients with axial AS. The immunological findings in patients with peripheral and axial form of AS were different from each other and thus may reflect different aetiopathogenetic mechanisms for these two types of AS.
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7788167
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Frequency of autoantibodies to a major epitope on the carboxyl terminal fragment of CENP-B in patients with autoimmune disease.
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The carboxyl-terminal fragment of CENP-B contains a major epitope for anti-centromere antibodies (ACA). We have developed an enzyme-linked immunoassay (ELISA) for measuring antibodies to the 147-carboxyl-terminal amino acids of CENP-B expressed as a beta-galactosidase fusion protein. The ELISA was 98% sensitive and 95% specific for detecting ACA in a population which included 46 patients with ACA detected by other means. Therefore, the CENP-B ELISA should prove a valuable tool in screening for ACA in populations at risk of developing systemic sclerosis, such as those with Raynaud's phenomenon. Levels of anti-CENP-B antibodies were not increased in unaffected relatives of probands with ACA.
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7788158
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Steroid myopathy induced by epidural triamcinolone injection.
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Epidural steroid injections are widely used for the treatment of lumbago and sciatica although their efficacy has not yet been demonstrated in a convincing way. Moreover, systemic complications, although rare, have been documented. The present case report illustrates that even a single low-dose epidural injection may induce Cushing's syndrome and even steroid myopathy.
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7788157
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Sulphasalazine-induced lupus in psoriatic arthritis.
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Lupus syndromes have been described in rheumatoid arthritis and inflammatory bowel diseases treated with sulphasalazine. We describe two cases of lupus with clinical and serological disease, developing in seronegative, immunologically nude psoriatic arthritis following sulphasalazine treatment. On cessation of sulphasalazine the clinical and serologic features of lupus disappeared. This suggests that the lupus syndrome was induced by sulphasalazine rather than unmasked by it.
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7788156
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Role of prophylactic antibiotics in the prevention of late infection of prosthetic joints. Results of a questionnaire and review of the literature.
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A postal survey has revealed wide variation in attitudes towards the need for prophylactic antibiotics in patients with implants who develop intercurrent infections, or who undergo surgical procedures. The available evidence is insufficient to reach any firm conclusions, however any patient who has an implant should receive swift treatment for intercurrent infections.
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