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7787977
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Gait analysis of the donor foot in microsurgical reconstruction of the thumb.
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Clinical and step evaluations by a piezoelectric system board were performed in 54 patients who underwent microsurgical reconstruction of the thumb by great or second toe transfer. Forty-four patients were male and 10 were female. In 13 cases, the thumb was reconstructed by the Morrison wrap-around technique. In 27 cases, an extended variant of the Morrison technique was used in which the whole distal phalanx was harvested with skin and nail apparatus. Four patients were treated by great toe transfer and 10 were treated by second toe transfer. Follow-up ranged from 2 to 144 months. The group of patients treated by the wrap-around technique presented hallux rigidus in 38.5% of cases. The group of patients treated by the extended variant of the Morrison technique presented a lesser tendency to hallux rigidus but a clear reduction of the pushing phase of hallux. The group of patients treated by second toe transfer presented a third and fourth metatarsal bone overload that was confirmed by a statistical Wilcoxon test: overload was linked to a plantar hyperkeratosis at the third metatarsal (20%), fourth metatarsal (10%), or fifth metatarsal bone (20%). A claw deformity of the third and fourth toes was observed in 20% of these patients. The four patients who underwent microsurgical reconstruction of the thumb by great toe transfer exhibited an overload of central and lateral metatarsal bones. Second toe transfer is not associated with the functional or cosmetic changes seen in great toe transfer and is therefore preferred.(ABSTRACT TRUNCATED AT 250 WORDS)
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7787976
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Distraction osteogenesis for congenitally short lesser metatarsals.
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Six lesser metatarsal lengthening procedures were performed in three patients using a miniature external fixator to perform distraction osteogenesis. The metatarsals were lengthened an average of 15.5 mm. The external fixator was left in place for an average of 15.5 weeks, with additional time in a cast or cast shoe. Complications included five occurrences of infection, two cases of premature healing of the osteotomy, one nondisplaced fracture through the new bone formation, and hypertrophic granulation at a pin site. While all metarasals were successfully lengthened, two rays (one patient) had symptomatic stiffness at the metatarsophalangeal joint with continued metatarsalgia.
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7787972
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Hallux valgus correction using a modified Hohmann technique.
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In 181 patients presenting with hallux valgus (247 toes), we performed a modified Hohmann procedure with Kirschner wire fixation of the osteotomy. Follow-up by a questionnaire was possible in 159 patients representing 217 operated toes (21 reoperations), and roentgenograms of bony healing were assessed in all these patients. The questionnaire was returned by 91% (145/159) of the patients. The average observation time was 52 months (25-97 months). The average correction of the hallux valgus angle was 10 degrees, ranging from 31.4 degrees before surgery to 21.4 degrees after surgery. Eighty-eight percent of the patients stated that they had an excellent or good/fair result, and 12% had pain or problems with footwear. We found a positive correlation among the correction of the valgus angle, the lateral displacement, shortening of the first metatarsal, and the overall result. No correlation was found among the plantar displacement, correction of the intermetatarsal angle and the result. The modified Hohmann procedure is, in our opinion, a safe and reliable procedure for treating hallux valgus deformity of the foot.
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7787975
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The strength of Achilles tendon repair: an in vitro study of the biomechanical behavior in human cadaver tendons.
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Eighteen fresh frozen human Achilles tendons were used to test the ultimate strength of repaired tendon "ruptures." Three methods, the Kessler, the Bunnell, and the locking loop, were used to test the initial strength of Achilles tendon repair. The Kessler and Bunnell methods are current standard clinical configurations described for Achilles tendon repair. Under uniform and standardized laboratory conditions, the specimens were loaded to failure. The locking loop suture method was substantially stronger than either of the other two standard configurations. The latter two did not differ significantly from each other. The results of this study may be clinically relevant in terms of the choice of the repair method for surgically treated Achilles tendon ruptures.
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7787971
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Effect of grape seed tannins on the activity of some rat intestinal enzyme activities.
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The present study was designed to investigate the effects of grape seed tannins on rat intestinal alkaline phosphatase (AP), sucrase and dipeptidyl peptidase IV (DPP IV) activities. An experiment was performed in vivo by dietary supplementation with 2% tannins; this diet was tested on an experimental group of rats; a control group received a diet without tannins. After 31 days, tannins intake significantly decreased middle-jejunal AP from 123 to 45 mU/mg protein and sucrase activities from 310 to 195 mU/mg protein, while no significant difference appeared at the duodenal stage (p < 0.05). Ileal DPP IV activity was also significantly reduced (p < 0.05) from 190 to 110 mU/mg protein after tannin intake. Using in vitro experiments on purified brush border membranes, AP activity was found to be inhibited by grape tannins; this inhibition was prevented by the detergent Triton X-100. The addition of pancreatic-biliary (PB) juice to the incubation medium prevented or reversed the tannin-inhibited enzyme activity. The present data indicate that in the duodenal lumen, alkalinity and detergency from the PB secretion neutralized the ability of tannins to inactivate brush border hydrolase activities and suggest that enzyme inhibition took place once bile salts were reabsorbed while moving down the gut. This was confirmed by in vitro experiments where sucrase and DPP IV activities inhibited by grape seed tannins were largely recovered after the addition of PB juice to the incubation medium.
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7787973
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The short oblique fracture of the distal fibula without medial injury: an assessment of displacement.
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Eighteen patients with ankle injuries presenting as short oblique fractures of the distal fibula with no clinical or radiographic evidence of injury to the medial ankle were studied for fracture displacement. Plain radiographs and computed tomography were used for analysis. All fractures were clinically diagnosed as supination-external rotation stage 2 (SE-II) injuries under the Lauge-Hansen scheme. All exhibited slight displacement on plain radiographs and were treated nonoperatively. Computerized tomography using axial cuts across the fracture site and ankle mortise revealed normal positioning of the talus beneath the tibial plafond, as evidenced by no abnormality of the medial joint space in all patients. In the majority of patients, the relationship between the talus and distal fibula also appeared undisturbed, with fracture displacement being confined to a change in position of the proximal fibular fragment relative to the tibia as compared with the contralateral ankle. In a minority of cases, in addition to the above-described displacement of the proximal fibular fragment, the distal fibular fragment was noted to shift slightly laterally relative to the talus, with mild widening of the lateral joint space. Occult-associated avulsion fractures off the distal tibia were present in 39% of the cases.
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7787974
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Distal tibia bone graft for arthrodesis of the foot and ankle.
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Forty patients since 1988 have had distal tibial bone grafting for 41 arthrodeses of the foot and ankle. Bone graft is obtained through a cortical window made just above the medial metaphyseal distal tibial flare. Average follow-up was 23.3 months. Forty of 41 arthrodesis sites fused; there was only one nonunion. There were no delayed unions. There were no complications at the donor site based on patient examination and radiographs. Ipsilateral ankle motion was not affected by the bone graft procedure. Cited complications from iliac crest bone graft include donor site pain, blood loss, heterotopic bone formation, pelvic instability, iliac hernia, infection, fracture, and deformity. Complications with allografts include disease transmission and immune response. These are avoided by using locally obtained distal tibia autograft for arthrodeses in the foot and ankle.
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7787970
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Purification of human and rat kidney aldose reductase.
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In the present study we report on a rapid two-step affinity chromatographic procedure to purify aldose reductase from human and rat kidney papilla and inner medulla. This enzyme, which is responsible for sorbitol formation in the kidney, was purified 145-fold from rat and 76-fold from human kidneys by consecutive Blue Sepharose and Matrex Orange chromatography. SDS-PAGE showed a single band of 38 kD for the human enzyme and a doublet of similar molecular weight for the rat kidney aldose reductase. The enzyme was characterized by substrate specificity and kinetic constants found identical to that of other organs purified previously.
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7787969
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Induced expression of alpha-enolase in differentiated diffuse large cell lymphoma.
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A unique protein has been detected that is associated with the differentiation of diffuse large cell lymphoma (DLCL). The WSU-DLCL human cell line was cultured in the absence or presence of the biological agent, Bryostatin 1 (Bryo1). Cellular proteins of parent and differentiated WSU-DLCL cells were analyzed using one- and two-dimensional polyacrylamide gel electrophoresis (1D and 2D PAGE). In the 1D PAGE, a unique protein band of molecular mass approximately 47 kD was detected in the differentiated, but not the parent cells. Amino acid sequence of the band indicated the presence of more than one protein. The 2D PAGE analysis showed that one of the proteins of interest had an isoelectric point of 7.4. Partial amino acid sequencing of the spot by tryptic digest showed 100% homology with alpha-enolase. alpha-Enolase is a nonneuronal enzyme involved in the glycolytic pathway. This is the first report on the induction of alpha-enolase in human DLCL after treatment with the natural biological agent, Bryo1. We suggest that alpha-enolase may play a significant role in the differentiation of lymphoma in man.
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7787968
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Structural characterization of cytosolic NADP(+)-dependent isocitrate dehydrogenase from rat ovary.
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Cytosolic NADP(+)-dependent isocitrate dehydrogenase was purified to homogeneity from superovulated rat ovaries. Amino acid sequence information was obtained by analyzing peptides generated by digestion with either cyanogen bromide or trypsin. Eleven peptides were sequenced and a total of 146 amino acids were identified. Nine of these peptides were found to be 60-100% identical with sequences from mitochondrial NADP(+)-dependent isocitrate dehydrogenase. Conservation of amino acids was observed for residues that were previously identified as potentially binding isocitrate-Mg2+. Circular dichroism measurements showed that the structure is composed of approximately 35% alpha-helix and 21% beta-sheet segments. Temperature denaturation studies indicated that the enzyme is more stable in the presence of isocitrate.
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7787967
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Clinical evaluation of serum ornithine carbamoyltransferase by enzyme-linked immunosorbent assay in patients with liver diseases.
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We developed a sensitive enzyme-linked immunosorbent assay (ELISA) for serum ornithine carbamoyltransferase (OCT) protein, and examined serum OCT concentrations in patients with various liver diseases. OCT concentrations were markedly elevated in cases of hepatic encephalopathy, 'acute on chronic', and those with the acute phase of acute hepatitis, moderately in chronic hepatitis, liver cirrhosis, hepatocellular carcinoma, primary biliary cirrhosis, and slightly in those with a fatty liver. High percentages (92-98%) of patients with chronic hepatitis, liver cirrhosis and hepatocellular carcinoma had higher than normal concentrations of serum OCT protein. There was a close correlation with aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities and moderate correlations with those of mitochondrial AST, glutamate dehydrogenase and gamma-glutamyltranspeptidase. The OCT/ALT ratio was higher in patients with liver cirrhosis than in those with chronic hepatitis (p < 0.001), and was still higher in cases of hepatocellular carcinoma (p < 0.05). In 2 patients with 'acute on chronic' disease, OCT concentrations decreased similarly with or more rapidly than AST or ALT activities after admission. In 2 patients with hepatic encephalopathy, the OCT concentrations changed similarly with AST and ALT activities. This OCT ELISA system will aid in diagnosing various liver diseases and in the follow-up of the patients, and the OCT/ALT ratio may serve for a differential diagnosis of liver diseases.
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7787966
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A sensitive enzyme-linked immunosorbent assay of serum ornithine carbamoyltransferase.
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Ornithine carbamoyltransferase (OCT), a urea cycle enzyme, is located almost exclusively in liver mitochondria. We designed a sensitive enzyme-linked immunosorbent assay (ELISA) of serum OCT protein using an antibody against purified bovine enzyme. OCT protein measured using this method showed a good correlation with OCT activity (r = 0.961), and was much higher in patients with liver diseases than in the controls. Measurements of serum OCT protein in 442 healthy blood donors gave the upper limit of normal range of 23 ng Eq/ml (equivalent to the bovine enzyme) for males, 8 ng Eq/ml for females, and 16 ng Eq/ml for males plus females. The values differ significantly between the sexes and depending on ages. This ELISA system is expected to be used as a pertinent liver function test.
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7787965
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Kinetics of irreversible inhibition of creatine kinase during modification by o-phthaldehyde.
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It has been previously reported that, with a fluorescence probe formed from o-phthaldehyde (OPTA) and the thiol and amino groups at or near the active site of creatine kinase, inactivation and exposure of the probe take place simultaneously and well before unfolding of the molecule as a whole. In this study, the inactivation and modification kinetics of purified rabbit muscle creatine kinase by OPTA have been compared, the former by following the substrate reaction in the presence of a previously described inactivator. The microscopic rate constants for the reaction of the inactivator with the free enzyme and with the enzyme-substrate complexes were determined. From the results obtained it appears that OPTA is noncompetitive with respect to both substrates. The inactivation kinetics is monophasic with OPTA, and neither ATP nor creatine alone affect the rate constant of inactivation of the enzyme, indicating that the irreversible inhibition of creatine kinase by OPTA is of the noncompetitive type.
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7787964
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Orthotic treatment of the hand. What's new?
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Keeping abreast of the latest orthotic products is challenging. Commercial orthoses need to be critically evaluated for their applicability to the person with rheumatic disease. Custom-made orthoses play an invaluable role in achieving a wide range of therapeutic goals: improving function and pinch, stabilizing individual joints, preventing positional contractures, protecting joints from trauma, stretching the intrinsic muscles, correcting joint- and soft-tissue contractures, and controlling inflammation.
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7787960
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Ombudsmen, patient complaints, and total quality management: an examination of fit.
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In response to mounting health care costs in the United States and Canada, there is considerable national discussion of health care quality, including the importance of assessing and monitoring patient satisfaction and of responding to complaints. Many physicians and health care administrators cringe at the mention of using patient complaints and satisfaction levels as quality measures; others perceive the need to develop multiple source indicators of patient care. At the same time, leaders are seeking programs and methods that contribute to the continuous improvement of all aspects of health care organizations. The use of patient ombudsmen and patient complaints in quality management programs is reviewed and the relation between the two functions--ombudsmen/complaint handling and total quality management--is discussed. Purposes, objectives, problem-solving processes, program operations, data use, and the outcomes of ombudsmen efforts are reviewed. Since ombudsmen programs value patient feedback, empower customers, and help contribute to the diagnosis of organizational areas for improvement, they are consistent with the intent and workings of quality teams. The activities of ombudsmen can contribute to the broader effort to manage the whole organization toward the continuous improvement of quality.
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7787959
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Computer-assisted quality improvement in an ambulatory care setting: a follow-up report.
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The Quality Care Program (QCP), introduced into the Swedish Family Medicine Clinic in 1992, is a comprehensive computer-assisted program of quality improvement for the medical office. Its goal is to improve specific aspects of ambulatory patient care: disease prevention, cancer detection, immunization compliance, risk management, outcomes monitoring, and patient education. The QCP uses a computer-generated worksheet that is attached to the medical record at each patient visit. It is a multipurpose worksheet that displays important clinical information and functions as part of an overall strategy to manage key aspects of the patient's care. The system enhances patient and physician performance of health maintenance and continuity of care, and it allows for the quantification and display of performance indicators without exclusive reliance on chart review. Physician reliability in recommending health maintenance interventions has improved to nearly 100%, and patient compliance with these recommendations has significantly increased. The test results tracking system has found test data that would have otherwise been lost, and the outcomes monitoring has resulted in measurable system improvements. There has been a modest increase in provider workload to meet these aggressive QCP goals, but measures of provider satisfaction have increased nonetheless. Ambulatory care, increasingly the focus of attention in the United States, can be difficult to perform well. The QCP, part of an overall quality improvement initiative, gathers and displays clinical information, reminds patients and physicians to do health maintenance, and refuses to let physicians and patients forget about specific aspects of patient care.
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7787957
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Prognostic factors for preoperative consultation of women desiring sterilization: findings of a retrospective analysis.
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In this exploratory study, 37 sterilized women applying for sterilization reversal were questioned thoroughly to establish why they had decided to undergo sterilization and why they now wished for it to be reversed. Taking an interactive behavioral model as our starting point, we concentrated on the psychosocial circumstances leading to the definitive decision to be sterilized. A relationship crisis at the time of sterilization was found to be a prognostically unfavorable factor. Furthermore, 20 of the 37 patients cited new partnerships as their main reason for seeking reversal. Those who felt pressurized by their gynecologist or partner into undergoing sterilization had significantly more problems in overcoming the psychological stress accompanying such an operation than those who, through a series of consultations on contraception, had had sufficient time and opportunity to make their own decisions. Sterilization performed for medical reasons was found to have particularly problematical consequences, especially where the doctor had made the decision largely on his own, failing to give an adequate explanation for the medical necessity of the operation. Regarding the time chosen for sterilization, the study revealed that the patient's postoperative psychological condition was significantly worse when sterilization was carried out immediately after a delivery, after abortion or after Caesarean section, rather than in the interval between pregnancies. The resulting increase in the incidence of psychosomatic complaints and depressive states is also confirmed in the literature. The findings of this study offer practical suggestions for improved preoperative consultation and should help to determine the course of action to be taken when a patient wishes to be sterilized.
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7787958
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Public reporting of performance measures in home care.
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In 1992 DependiCare Home Health, Inc (Broadview, Ill), a 62-employee home medical equipment/respiratory therapy (HME) business in the Chicago metropolitan area, discovered that managed care organizations need quantifiable data from vendors in the form of measurements or outcomes. In response to this need, DependiCare developed its "Under the Microscope" program. This program provides quarterly reports (starting in April 1994) on service efficiency, patient satisfaction, and outcome statistics to referral sources, including physicians, discharge planners, and hospital executives. Performance measures, which represent information from DependiCare's internal operations, can be viewed as the company's quarterly report card. Areas reported on include target-time performance, same-day and under-two-hour delivery, patient (and referral source) satisfaction, equipment breakdown, and fillrate statistics. Outcome statistics include discontinuation of service by diagnosis and number of months on oxygen by diagnosis. USE OF RESULTS: Measurements help to identify weaknesses that need to be addressed by organizational or operational changes, as well as to uncover strengths that can be capitalized on for sales and marketing. Hospital-based discharge planning departments, a substantial referral source, most often use the Under the Microscope program to justify referring patients to DependiCare. Little is known about managed care customers' use of the data. In the long term, an integrated, automated way to track individual patients across the continuum of care from the physician, to the hospital, and to home care is needed. A centralized database of patient experience, including outcomes, could assist in health care decision making.
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7787956
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University students' subjective experiences of oral contraceptive use.
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A substantial proportion of women who commence oral contraceptive discontinue usage due to unwanted side-effects. In investigations of side-effects in current users, such women are excluded, and hence such studies will tend to underestimate the prevalence of side-effects. One hundred and forty-five female university students (both former and current users) completed a questionnaire focusing on their experiences of the impact of oral contraceptives upon their psychological and physical well-being. Although, on average, over half the women reported no effect, the vast majority of those who did report a change in well-being deemed this to be negative. The only exception was pelvic pain which was reported to be improved by oral contraceptive use.
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7787955
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Premenstrual complaints: an idiosyncratic syndrome.
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The two issues of premenstrual syndrome (PMS) symptom heterogeneity and symptom severity are addressed in an examination of the idiosyncratic nature of premenstrual complaints. Analyses of PMS symptoms reported during the first assessment month by a group of treatment-seeking women revealed that when presented with a prepared list of symptoms (Menstrual Distress Questionnaire), they select many more symptoms than when self-reporting their complaints in ranked order of severity. In this study of a sample of 98 women, most of the women reported only four rank-ordered symptoms. Symptom profiles from five symptom categories were constructed for each of the women and from a possible 86 different profiles 84 were discovered. Of these, psychological profiles dominated the total reports. These findings, together with results of previous research, lead to two conclusions. First, that PMS, though multidimensional, may be defined for each woman by a limited number of symptoms; and second, that PMS is highly idiosyncratic in nature.
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7787954
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Medical history in women with premenstrual syndrome.
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This study was designed to identify significant factors in the medical history of women with premenstrual syndrome (PMS). Medical history variables of 190 women with PMS were compared with those of a group of 182 women without premenstrual symptoms who sought gynecological care (control group). All the participants were carefully selected by interview and designated questionnaires. Women with a past or present psychiatric history were excluded. The results showed that age, number of children, age of menarche, smoking history and family history of psychiatric disorders of the women with PMS and the controls were similar. Women with PMS exhibited a significantly greater frequency of postpartum depression (43% versus 12%), past birth control pill use (91.6% versus 45.9%), alcohol use (39.5% versus 14.8%) and drug use (48.4% versus 14.1%) than did the controls respectively; all p values were < 0.05). Our data suggest an association between these factors and PMS. They should be identified in women with premenstrual complaints during the initial visit, and the roles of these factors in the pathophysiology of PMS need to be further investigated.
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7787953
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Non-traditional mothers: single heterosexual/lesbian women and lesbian couples electing motherhood via donor insemination.
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The purpose of the project was to explore the motivation, reproductive and postdelivery experiences, and future concerns of single heterosexual and lesbian women and lesbian couples who attempted conception via donor insemination (DI). All women who had completed at least one cycle of DI between 1987 and 1992 at a large medical school infertility program were mailed a comprehensive 'Motherhood' questionnaire. Forty-five women completed the survey (response rate = 88%) of whom 14 were lesbians, 28 were heterosexuals, two were bisexual and one was celibate. The only major differences between the heterosexual women and the lesbian women were that the heterosexual women were older and had started DI attempts at an older age than the lesbian women. The majority of women reported that four major considerations prompted their decision to initiate DI when they did: feeling secure in their employment, the sense that time was running out, feeling that they had 'worked through' concerns about parenting, and that they had sufficient social support. Three characteristics were deemed moderately or very important in their selection of sperm donors: ethnicity, education and height. After achieving a pregnancy, most women wished to know more detailed information about their donor. Unlike heterosexual couples, all single and lesbian women planned to disclose the fact of DI to their offspring but were uncertain of when or how to accomplish this. The greatest worry reported by respondents was how their child would deal with the absence of a known designated father. Overall, the women were gratified with their experience of DI, and the majority would 'absolutely' recommend it to a friend.
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7787952
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Private health insurance and a healthy personality: new risk factors for obstetric intervention?
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In this study 242 nulliparous pregnant women completed standardized psychometric questionnaires and semi-structured interviews in the latter half of pregnancy and again 4-6 weeks postpartum. Discriminant function analysis revealed that the use of operative obstetric interventions was measurably influenced by psychosocial factors. Privately insured women were significantly more likely to experience instrumentally assisted (relative risk = 1.53, 95% CI: 1.05, 2.25) and Caesarean (relative risk = 1.91, 95% CI: 1.05, 3.46) deliveries than those receiving care in the public hospital system. The likelihood of experiencing these procedures was increased further among those who in late pregnancy were thinking clearly, had high self-esteem, mature means of dealing with anxiety, were confident in their knowledge of childbirth procedures and in secure partnerships with highly educated men. There was no evidence that either elevated anxiety or abnormalities of personality contributed to obstetric outcome. These findings indicate that obstetric decision-making is significantly influenced by patient personality and socioeconomic circumstances. In particular, they suggest that fear of malpractice litigation, physician convenience factors and the response of obstetricians to assured, well pregnancy-educated pregnant women may be influencing the use of operative intervention in delivery.
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7787949
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Intracellular correlates of hippocampal theta rhythm in identified pyramidal cells, granule cells, and basket cells.
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The cellular-synaptic generation of rhythmic slow activity (RSA or theta) in the hippocampus has been investigated by intracellular recording from principal cells and basket cells in anesthetized rats. In addition, the voltage-, coherence-, and phase versus depth profiles were examined by simultaneously recording field activity at 16 sites in the intact rat, during urethane anesthesia, and after bilateral entorhinal cortex lesion. In the extracellular experiments the large peak of theta at the hippocampal fissure was attenuated by urethane anesthesia and abolished by entorhinal cortex lesion. The phase versus depth profiles were similar during urethane anesthesia and following entorhinal cortex lesion but distinctly different in the intact, awake rat. These observations suggest that dendritic currents underlying theta in the awake rat may not be revealed under urethane anesthesia. The frequency of theta-related membrane potential oscillation was voltage-independent in pyramidal neurons, granule cells, and basket cells. On the other hand, the phase and amplitude of intracellular theta were voltage-dependent in all three cell types with an almost complete phase reversal at chloride equilibrium potential in pyramidal cells and basket cells. At strong depolarization levels (less than 30 mV) pyramidal cells emitted calcium spike oscillations, phase-locked to theta. Basket cells possessed the most regular membrane oscillations of the three cell types. All neurons of this study were verified by intracellular injection of biocytin. The observations provide direct evidence that theta-related rhythmic hyper-polarization of principal cells is brought about by the rhythmically discharging basket neurons.(ABSTRACT TRUNCATED AT 250 WORDS)
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7787950
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Simultaneous blockade of non-NMDA ionotropic receptors and NMDA receptor-associated ionophore partially protects hippocampal slices from protein synthesis impairment due to simulated ischemia.
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A large body of evidence exists to demonstrate that excitatory amino acids (EAA) and their receptors are involved in the pathophysiological mechanisms linking several acute brain insults, such as cerebral ischemia, to neuronal degeneration and death. Accordingly, the use of EAA receptor antagonists can be beneficial in attenuating or preventing the neuronal irreversible damage subsequent to various neuropathological syndromes. We have investigated the effect of 15 min of simulated ischemic conditions, i.e., oxygen/glucose deprivation, on hippocampal slices preparation measuring, as neurotoxicity indexes, both the amino acids efflux in the incubation medium, detected by HPLC, and the inhibition of protein synthesis, evaluated as 3H-Leucine incorporation into proteins. Accumulation of neurotransmitter amino acids was measured in the medium during the "ischemic" period. Glutamate increased 30-fold over the basal level while aspartate was sevenfold and GABA 12-fold higher than in normal conditions. After a reoxygenation period of 30 min, the rate of protein synthesis of hippocampal slices subjected to "ischemia" was reduced to 35-50% of controls. The non-competitive NMDA antagonist MK-801 (100 microM) and the competitive NMDA antagonist CGP 39551 (100-250 microM) as well as the non-NMDA receptor antagonists NBQX (100 microM) and AP3 (300 microM) were unable to counteract the metabolic impairment when they were present alone in the incubation fluid during simulated "ischemia." An incomplete, but highly significant (p < 0.001), protection from protein synthesis impairment was achieved in the presence of an equimolar concentration (100 microM) of MK-801 and NBQX.(ABSTRACT TRUNCATED AT 250 WORDS)
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7787948
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Adenosine antagonists have differential effects on induction of long-term potentiation in hippocampal slices.
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How adenosine leakage and tetanic release might affect long-term potentiation (LTP) was investigated by applying adenosine antagonists 8(p-sulfophenyl)theophylline (8SPT) or 8-cyclopentyl-3,7-dihydro-1,3-dipropyl-1H-purine-2,6-dione (DPCPX) to slices, while recording CA1 field EPSPs and population spikes. In the first series of experiments, we applied weak double tetani (at 100 Hz, for 1 s) that were subliminal for evoking LTP in initial control runs. In the presence of 8SPT--at concentrations (10-50 microM) which block both A1 and A2 receptors--the same tetani consistently evoked LTP of population spikes but not of excitatory postsynaptic potentials (EPSPs), whereas DPCPX (50 nM), which blocks only A1 receptors, facilitated LTP of both EPSPs and population spikes. These results are consistent with previous evidence that tetanic adenosine release on the one hand depresses LTP via A1 receptors but on the other facilitates LTP via A2 receptors. In a second set of experiments, 8SPT (50-100 microM) did not prevent the induction of LTP of both EPSPs and population spikes by stronger tetanic stimulation. Therefore A2 receptor activation is not essential for the induction of LTP when stronger tetani are applied. Overall, the main effect of endogenous adenosine release is to oppose LTP induction.
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7787947
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NADPH diaphorase-positive neurons in the lizard hippocampus: a distinct subpopulation of GABAergic interneurons.
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We analyzed the distribution and light-microscopic features of the NADPH diaphorase-containing structures in the lizard hippocampus, likely to correspond to nitric oxide synthase-containing cells and fibers, and thus likely to release nitric oxide. We also studied co-localization of NADPH diaphorase with the neurotransmitter GABA, the calcium-binding protein parvalbumin, and the neuropeptide somatostatin, in order to examine whether putative nitric oxide-synthesizing neurons represent a different subpopulation of GABA cells, on which the authors recently reported in lizards. We also studied co-localization of NADPH diaphorase with parvalbumin or somatostatin in mice to ascertain whether the characteristics of this population in reptiles parallel the situation in mammals. Most of the positive NADPH diaphorase neurons were stained in a Golgi-like manner and were in the plexiform layers of the lizard hippocampus with morphologies ranging from bipolar to multipolar. Co-localization with GABA was 100%, and NADPH diaphorase-positive neurons in the lizard hippocampus did not contain parvalbumin or somatostatin. The results indicate that putative nitric oxide-synthesizing neurons represent a distinct subpopulation of GABA interneurons in the lizard hippocampus. Two different types of fibers were described in the plexiform layers: one type bearing thick varicosities, and the other thinner ones. We discuss the possibility that at least part of the positive fibers arise from a hypothalamic aminergic nucleus contacting the third ventricle, the periventricular hypothalamic organ. Most radial glia were stained almost completely and formed typical end-feet both at the pia and around capillaries. The results of this study confirm that the capacity for synthesizing nitric oxide is linked to a determined set of neuronal markers depending on the specific brain region, and they provide new resemblances between hippocampal regions in different classes of vertebrates.
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7787946
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Reduction of the threshold for long-term potentiation by prior theta-frequency synaptic activity.
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Activation of the lateral perforant path input to the dentate gyrus with theta-patterned conditioning trains produced LTP of synaptic efficacy that changed in magnitude as an inverted U-shaped function of the number of trains. The LTP induction function was not fixed, however, and could be shifted to the left by administering 5 Hz "priming" stimulation to the lateral path 10 min prior to the conditioning trains. The priming effect was input specific and selective to a narrow window of stimulus frequencies. The shift to the left of the LTP induction function by priming stimulation was blocked by the muscarinic receptor antagonist atropine sulphate. Nimodipine, an antagonist of L-type voltage-sensitive calcium channels, did not mimic the priming effect but instead produced a general facilitation of LTP induction. These data demonstrate that the degree to which LTP is induced in the lateral path is a non-linear function of afferent activity, and that this function, including LTP threshold, can be shifted to the left by prior synaptic activity at hippocampal theta-rhythm frequencies.
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7787945
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Activation of somatostatin-synthesizing neurons in the hippocampal formation through kindling-induced seizures.
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The present study was designed to determine if and to what extent somatostatin (SST) synthesizing neurons of the hippocampal formation are activated during seizures, elicited through kindling of the perforant pathway. Tissue was used and analyzed from animals which had experienced a single after discharge, or a stage 3 or stage 5 seizure. The protein expression of the oncogene c-fos in activated, depolarizing neurons was utilized to identify seizure-activated SST-synthesizing neurons. Combined immunocytochemical and in situ hybridization methods were used to identify these double-labeled, Fos protein, and SST mRNA-containing neurons. The results were quantified and compared across seizure stages. The resulting data demonstrate that at every stage of seizure development, a majority of SST-synthesizing neurons is activated, but that these activated SST mRNA-containing neurons represent only a minority of all seizure-activated, Fos-expressing neurons in the hippocampal formation. The data further reveal a numerical hierarchy in which the majority of double-labeled neurons is present in the hilus of the dentate, followed by the stratum oriens of CA1. It is concluded that SST-synthesizing neurons represent an integral component of the kindling activated neuronal network and, since the SST synthesizing neurons represent the minority of all seizure-activated neurons in the hippocampal formation, that this neuronal network is likely to be of considerable neurochemical complexity.
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7787944
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Correlation of anoxic neuronal responses and calbindin-D28k localization in stratum pyramidale of rat hippocampus.
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Immunohistochemical staining for the calcium-binding protein calbindin-D28k (CaBP) was combined with Lucifer Yellow (LY) identification and intracellular recording of changes in membrane parameters of pyramidal neurons in CA2, CA1, and the subiculum of rat hippocampal slices during brief exposure (4.0 +/- 0.19 min) to N2. Anoxia evoked either a depolarization or hyperpolarization of membrane potential (VM) (+21.5 +/- 2.79 mV above VM = -70.5 +/- 1.50 mV, n = 30 and -7.2 +/- 0.72 mV below VM = -68.2 +/- 1.34 mV, n = 24, respectively) and a fall in membrane resistance of approximately 20%. Differences in the response could be correlated with the presence or absence of CaBP and the localization of neurons in different layers of stratum pyramidale and sectors of the hippocampus. For neurons immunopositive for calbindin (CaBP(+)), depolarization was observed more frequently (83%) than hyperpolarization (17%); in contrast, 44% of responses of calbindin-negative (CaBP(-)) neurons were depolarizing and 56% were hyperpolarizing. Depolarizations of CaBP(+) neurons were more gradual in slope, and more rapidly reached a plateau in comparison with those recorded in CaBP(-) neurons. Responses of neurons in the superficial layer of stratum pyramidale (in which 79% of CaBP(+) pyramidal neurons were situated) were mainly depolarizing (91%), while for those in the deep layer (which contained 89% of the CaBP(-) cells) such responses were observed less often (45%). Depolarization was also more common than hyperpolarization for cells located in CA2/CA1c/CA1b (63%) than in the CA1a/subicular region (37%). The depolarizing response of the majority of pyramidal neurons which are CaBP(+), superficial, and closer to CA3 may reflect an efficient buffering of intracellular Ca2+, which maintains a low [Ca2+]i, steep gradient for Ca2+ influx and may facilitate the movement of Ca2+ away from points of entry. The neurons which are CaBP(-), deep, and closer to subiculum and in which N2 evokes hyperpolarization, on the other hand, may have a sustained elevation/accumulation of cytosolic Ca2+ which could activate K+ conductance, inhibit Ca2+ influx, and stabilize the membrane potential. These experiments provide a functional correlate for CaBP and suggest that it may have a significant role in Ca2+ homeostasis and the determination of selective neuronal vulnerability.
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7787943
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Interhippocampal synthesis of lateralized place navigation engrams.
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Rats were trained in a water maze in a dark room with the extramaze cues restricted to only dimly back-lit shapes. We used lidocaine to reversibly lesion the dorsal hippocampus and this controlled-cue room in order to examine interhippocampal synthesis of lateralized place engrams. Experiment 1 showed that lidocaine injected into both hippocampi effectively abolished place navigation for up to 25 min but not at 45 min. In experiment 2, each day under lidocaine blockade of one hippocampus, pretrained rats were trained in the water maze to locate the target according to two cues (e.g., AB). Two hours later, the contralateral hippocampus was inactivated and the rats were trained to the same location with two other cues (CD). On day 5, intact brain retrieval was tested in one of three conditions: ACQ (e.g., AB), one of the pairs of cues used in acquisition training; SYNTH (e.g., AC), one cue from each of the pairs used in acquisition; CONT (e.g., AE), one cue that was used in acquisition training and a novel cue. The results show that the hippocampi learned the two tasks independently and similarly [latency (L) at the asymptote = 7 s]. Retrieval performance was at the asymptote for ACQ (AB) and SYNTH (AC) (L = 6 and 7, respectively) but was disrupted for CONT (L = 12). In experiment 3 as in experiment 2, the rats were trained, under unilateral blockade, to a new place for 4 days. On day 5, retrieval with the trained hippocampus blocked was worse (L = 11) than with the untrained side blocked (L = 5).(ABSTRACT TRUNCATED AT 250 WORDS)
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7787942
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Dentate gyrus destruction and spatial learning impairment after corticosteroid removal in young and middle-aged rats.
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We investigated the functional and behavioral implications of chronic corticosteroid removal in young and middle-aged rats. Prepubertal and 13-month-old rats were adrenalectomized (ADX) or sham operated (SHAM). The young ADX rats were divided further into three groups: ADX with no hormone replacement, ADX given corticosterone chronically, (chCORT), and ADX given corticosterone acutely at the time of Morris water maze testing (acCORT). All rats were run on the Morris water maze 12 weeks after surgery. They were then sacrificed and the brains were removed for histological analysis. The results showed that prolonged corticosteroid absence caused major damage to the dentate gyrus and learning impairment on the Morris water maze. The chCORT rats had little dentate gyrus cell loss and were as efficient as the controls in Morris water maze performance, whereas the acCORT rats had dentate gyrus cell loss and were impaired in the spatial acquisition task. Furthermore, exogenously administered corticosterone had an interactive effect on ADX rats. Water maze performance was improved in dentate gyrus damaged rats (acCORT) compared to ADX rats not given corticosterone, whereas ADX rats with very little dentate gyrus damage (chCORT) did not exhibit better water maze performance relative to controls. Middle-aged ADX rats lost cells only in the dorsal blade of the dentate gyrus but they did not show a learning impairment in the Morris water maze relative to the middle-aged controls. These results indicate that corticosteroids are trophic for the dentate gyrus, that mature granule cells are less affected by adrenalectomy, that corticosteroid absence is responsible for some water maze impairment in ADX rats, but that in addition to corticosteroid absence, a substantial amount of dentate gyrus damage is necessary to impair spatial learning.
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7787941
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Child abuse, sudden infant death syndrome, and attention-deficit hyperactivity disorder.
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A review of recent literature helps to clarify normal variations in the physical examination of children who are thought to have been sexually abused. In many instances, no abnormal physical findings are discovered. Clinicians must continue to pay careful attention to the history and work with other professionals to implement appropriate management, despite the lack of physical findings. Guidelines for evaluating sudden and unexpected infant deaths are reviewed. The current recommendations of the American Academy of Pediatrics for infant sleep positions are discussed in light of epidemiologic studies in the United States and other countries. Attention-deficit hyperactivity disorder appears to respond best to a combination of stimulant medication, parent training in coping with behavior of affected children, and social skill training for the affected children themselves. A review of recent research failed to reach consistent correlations between resistance to thyroid hormone and attention-deficit hyperactivity disorder.
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7787940
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Pharmacogenetics and development: are infants and children at increased risk for adverse outcomes?
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Over the past two decades, pharmacokinetic data have clearly demonstrated that development can markedly influence the absorption, distribution, excretion, and metabolism of xenobiotics. With respect to many of the processes that govern drug metabolism, the underlying pharmacogenetic determinants that may control either the affinity or the capacity of a drug or toxicant substrate for the enzymes responsible for its biotransformation appear to be altered as a function of development by mechanisms that are, for the most part, not well defined. Nonetheless, for many xenobiotics, the pharmacogenetic-developmental interface produces a "pattern" for drug metabolism that, when characterized, supports the pharmacokinetic properties (eg, drug clearance) reported for many agents across the pediatric age spectrum. With the exception of a few relatively well-characterized adverse drug effects (eg, toxicity of 6-mercaptopurine in patients with absent thiopurine methyltransferase activity, increased incidence of hepatotoxicity to valproic acid in young infants), the relationship of development and pharmacogenetics to enhanced toxicity risk from xenobiotic exposure is poorly defined. However, failure to adequately appreciate the pharmacokinetic consequences of the pharmacogenetic-developmental interface and to individualize therapy accordingly may lead to a clinically significant risk of drug therapy, namely, over- or underdosing.
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7787939
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Therapy of pediatric AIDS.
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Therapy of pediatric AIDS utilizes antiretroviral compounds; antibiotic, antifungal, and antiparasitic agents; and both active and passive immunization in a multifactorial approach. Currently, newly diagnosed pediatric AIDS cases are acquired predominantly through vertical transmission from HIV-infected mothers. Pediatric AIDS research is focused on strategies to prevent vertical transmission of HIV infection as well as therapy against opportunistic and progressive HIV disease. Zidovudine remains first-choice therapy for HIV infection and can reduce the rate of vertical transmission of HIV. Didanosine is also approved to treat HIV infection in pediatric AIDS. Other reverse transcriptase inhibitors are under investigation as alternative or combination therapies because of HIV resistance to zidovudine and didanosine. Alternative therapies for opportunistic infections are being investigated. Passive immunity with intravenous immunoglobulin is being reevaluated to determine efficacy in combination with other therapies. Finally, vaccination against usual childhood diseases with standard immunization schedules produces limited immunity, and alternative vaccination protocols warrant further investigation.
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7787938
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Renal toxicity of cancer chemotherapeutic agents in children: ifosfamide and cisplatin.
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Ifosfamide and cisplatin are two commonly used cancer chemotherapeutic agents associated with significant acute and chronic renal toxicity. The clinical characteristics of ifosfamide-induced renal injury are proximal tubular wasting of glucose, phosphate, bicarbonate, sodium, potassium, and amino acids; proteinuria; and decreased glomerular filtration rate. Cisplatin administration may result in a dose-dependent reduction of glomerular filtration rate, hypomagnesemia, hypokalemia, and polyuria. The characteristics of renal toxicity associated with each of these agents are discussed with attention to possible mechanisms of injury and long-term clinical outcome.
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7787937
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Pharmacotherapy of depression in children.
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Depression can interfere with the overall functioning of children and adolescents. It can impair normal cognitive and social development. The use of antidepressant medications in children and adolescents has grown in the past decade. Newer antidepressant agents, the selective serotonin reuptake inhibitors, appear very promising, but their safety and efficacy have not been established for children. This review focuses on depression and the design of studies for its treatment with newer antidepressant drugs in children.
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7787935
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Genetic renal diseases in children.
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In this review, a survey is given of genetic renal diseases in which recent progress has been made regarding the study of their molecular genetics. Diseases in which the responsible gene has been identified are discussed first, followed by a description of diseases in which successful chromosomal mapping has been achieved. The recent progress in this field will lead to advances in the diagnosis and understanding of the pathogenic mechanisms of genetic renal diseases and, potentially, will have implications for therapeutic interventions. The International Studies of Genetic Renal Diseases, which promotes the study of genetic renal disease, has recently provided an international database called kidbase, which is accessible via the Internet.
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7787936
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Status of drug approval processes and regulation of medications for children.
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The term therapeutic orphan was coined in 1968 to describe the exclusion of infants and children from approved indications for use of the majority of drugs approved by the US Food and Drug Administration (FDA). Although the 1962 Kefauver-Harris amendments to the Food, Drug, and Cosmetic Act were designed to insure the efficacy and safety of drugs approved for human use, infants and children have largely been excluded from the protection of the law. Approximately 80% of the drugs approved by the FDA during the past 30 years have been approved with a labeling disclaimer for use by children. This high percentage is due largely to the lack of studies in children to document safety and efficacy or a failure to use available data to amend labeling to include pediatric indications. Recently, several initiatives by the FDA and the National Institute of Child Health and Human Development have been implemented that promise to increase the number of drugs studied and labeled for children. These initiatives may introduce a new era of drug development for children in which pediatric investigators, the FDA, the National Institutes of Health, and the pharmaceutical industry join together to bring the same level of pharmacotherapeutic safety and efficacy to children that adult patients enjoy.
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7787934
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Focal segmental glomerulosclerosis in children.
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Idiopathic focal segmental glomerulosclerosis is a histologic diagnosis that usually presents as the nephrotic syndrome but, unlike minimal change disease, often leads to renal failure in children. Standard therapies used to treat the proteinuria are often futile, and thus patients are at risk for the multiple complications resulting from persistent, severe proteinuria. Eventually, end-stage renal failure ensues, and the possibility of the disease recurring in the transplanted renal allograft is worrisome. This report reviews the clinical features and outcomes of idiopathic focal segmental glomerulosclerosis in children, the response to newer treatment options, and new insights into understanding what factors may be involved in causing the disorder.
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7787933
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Chronic renal disease and growth in childhood.
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Growth failure, sometimes of a severe nature, has been recognized for many years as a consequence of chronic renal insufficiency (CRI) in childhood. The factors associated with growth failure, including renal osteodystrophy, anorexia and malnutrition, acidosis, salt wasting, and anemia, have also been recognized for many years. Despite vigorous treatment of these factors, patients with CRI continue to grow poorly. It was hoped that, with modern dialysis and transplantation, these patients would have normal growth or even catch-up growth and therefore overcome the height deficit that accrued during the time they had CRI. Unfortunately, this has not been the case. Although normal growth may be seen after transplantation, catch-up growth is rare. In the past year, studies have been reported demonstrating that supraphysiologic doses of growth hormone will produce catch-up growth in children with CRI. These reports are encouraging and are reviewed here.
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7787932
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Reflux nephropathy, urinary tract infection, and voiding disorders.
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Urinary tract infection (UTI), vesicoureteral reflux (VUR), and certain voiding disorders result in renal damage. In the past few years, the increasing use of 99mTc-dimercaptosuccinic acid renal scans, urodynamic testing, and antenatal sonography have helped shed light on the interrelationship of these disorders. Renal parenchymal involvement during acute febrile UTI and subsequent renal scarring are quite commonly observed in the absence of VUR, suggesting that the presence of reflux is not a prerequisite for renal damage. In infants with gross VUR, renal damage is often present at birth even before the development of any UTI. High intravesical pressures during bladder filling and voiding are commonly observed in infants with gross VUR, reflecting an underlying voiding dysfunction. High voiding detrusor pressures are also commonly observed in infants presenting with symptomatic UTI who do not have VUR. Children with dysfunctional voiding states are at risk for development of VUR and UTI. Renal damage in these children may occur in the absence of one or the other. This review elucidates how voiding dysfunction predisposes children to bacterial colonization of the bladder, the development or perpetuation of VUR, and renal damage.
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7787931
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Hemolytic uremic syndrome in children.
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The majority of postdiarrheal hemolytic uremic syndrome is caused by Escherichia coli O157:H7. The organisms are carried in the intestines of cattle; partially cooked contaminated hamburger is the single most common vector. The E. coli produce a potent cytotoxin that gains access to the circulation, is taken up by glycolipid receptors on glomerular endothelial cells, is internalized, and causes cell death. Associated phenomena include the activation of platelets, leukocytes, and the coagulation cascade, as well as the production of cytokines. Although some patients experience a mild or incomplete syndrome, life-threatening multisystem involvement can occur. Treatment is supportive, but plasma exchange may be useful in selected high-risk subsets. Efforts to prevent colitis from evolving into hemolytic uremic syndrome include the oral administration of material to bind the toxin in the gut. Mortality remains at 5% to 10%; about 4% are left with end-stage renal failure, and approximately 50% suffer mild chronic kidney damage.
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7787928
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Nutrition in the neonate.
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Good nutrition is of great importance for all living individuals, especially for the rapidly growing newborn infant. Nutrition is needed not only for the maintenance of physiologic functions but also for growth. Despite extensive research in this field, numerous questions remain regarding the nutrition of the term as well as the preterm infant. It should be stressed that the requirements of term infants are different from those of preterm infants, and a further distinction has to be made between very low birth weight and extremely low birth weight infants. In this review, the following issues are addressed: breastfeeding versus formula feeding, the role of polyunsaturated fatty acids, nutrition of the infant with bronchopulmonary dysplasia, and parenteral nutrition.
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7787927
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Potential for treatment of anemia of prematurity with recombinant human erythropoietin.
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Anemia of prematurity (AOP) results from several interacting processes, including phlebotomy losses, a temporary failure to release erythropoietin in response to anemia, a short life span of erythrocytes, and rapid growth of body mass and, hence, blood volume after the first few weeks of life. Infants with AOP have erythroid progenitors that respond to erythropoietin in vitro, suggesting that treatment with recombinant erythropoietin might reduce the need for transfusions for AOP. Many pilot studies were needed to define the dose of recombinant erythropoietin (500 to 750 U/kg/wk) that stimulated the early onset of erythropoiesis in infants with AOP. Three large controlled trials have demonstrated that recombinant erythropoietin therapy reduces transfusions in AOP and is apparently safe. Unresolved issues include the ideal dose, the optimal nutrition needed during therapy, the target population, and timing of the start of treatment.
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7787926
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Cerebral perfusion, metabolism, and outcome.
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Factors contributing to brain damage and an adverse outcome are complex. Both severe hypoxia-ischemia and prolonged hypoxia of lesser severity may cause brain damage. Compromised cerebral perfusion leads to ischemia. Fetal brain damage may begin because of a redistribution rather than reduction of cerebral blood flow. Normal newborn cerebral blood flow is low; fetal asphyxia at birth causes delayed cerebral hyperperfusion in the neonate. The threshold of newborn cerebral blood flow that is associated with brain damage has not yet been established. Hypoxia-ischemia will disrupt cerebral metabolism. The fetus can compensate for hypoxia up to a point; however, decompensation will occur when acidosis becomes severe. Normal newborn cerebral oxygen consumption is low compared with that in the adult; however, asphyxia, causing brain damage, is associated with abnormal newborn cerebral metabolism. Supplementary glucose may have a protective effect in the newborn brain. Hypoxia-ischemia will cause brain damage in the human fetus and neonate. There is a threshold of fetal asphyxia at birth when brain damage may occur. Sustained neonatal hypotension and hypoxemia are associated with brain damage and an adverse outcome.
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7787925
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Fetal toxicology of environmental tobacco smoke.
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During the past decade, new evidence has been collected regarding the fetal risks of environmental tobacco smoke. Throughout gestation, the unborn baby is exposed to increasing concentrations of nicotine through maternal blood and gastrointestinal and skin absorption of the nicotine in the amniotic fluid. Recent research shows measurable concentrations of cotinine in the hair of infants born to passively smoking mothers. This exposure has been recently associated with effects on fetal growth.
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7787923
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Associations between human and farm animal infections with Salmonella typhimurium DT104 in Herefordshire.
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Reports of human infection with Salmonella typhimurium definitive type (DT) 104 have generated considerable interest. We undertook a descriptive study of infections with S. typhimurium DT 104 infection in humans and farm animals in Herefordshire between 1991 and 1993. Laboratory reports of human salmonellosis, sent to the consultant in communicable disease control, were compared with cases identified using Statutory Incident Reports of salmonella in animals, birds and their products, received from the Ministry of Agriculture, Fisheries and Food. Six separate associations of infection between farming families and their livestock were identified. Nine out of 23 human cases, including three family outbreaks, were associated with animal infection. This study suggests that occupationally acquired infection in farmers and their families may be contributing to the national increase in cases, and shows the value of drawing together data from human and animal sources for the surveillance, investigation, and control of human infection with S. typhimurium DT104.
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7787922
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A case control study of infection with an epidemic strain of multiresistant Salmonella typhimurium DT104 in England and Wales.
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Laboratory reports of a multiresistant strain of Salmonella typhimurium definitive type (DT) 104 rose in 1993; this led the Public Health Laboratory Service to investigate cases and identify possible risk factors for infection. Information derived from questionnaires, and details of previous isolations of S. typhimurium DT104 from food and animals, were used to design an unmatched case control study. Eighty-three cases whose isolations were of the same plasmid profile type (the 'epidemic strain') and 235 controls were included in the analysis. Illness was independently associated with the consumption of several food items and contact with animals, particularly ill farm animals. The number of isolations of this organism continues to rise, and control measures may include reducing infection in animals used for food, reducing the risk of contamination at all stages of the food chain, and raising awareness of measures to prevent food poisoning among food handlers and the general public.
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7787920
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Outcome of an exercise to notify patients treated by an obstetrician/gynaecologist infected with HIV-1.
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Experience with hepatitis B suggests that the risk of HIV transmission from a health care worker infected with HIV to a patient will be greatest during major surgical procedures. The number of patients worldwide who are known to have undergone such procedures, been notified, and subsequently tested is still too small to be confident that the risk of HIV transmission in these circumstances is negligible. We describe a patient notification exercise, undertaken in the United Kingdom in 1991. Attempts were made to contact 1217 patients, in three health districts (A, B, and C), who had undergone surgical procedures performed by an obstetrician/gynaecologist who was infected with HIV. The exercise aimed to offer the patients reassurance, counselling and--if they wished--HIV testing. One thousand one hundred and forty-two patients (94%) were contacted, and all 520 who elected to be tested were negative for anti-HIV. The proportion of identified patients tested was 63% in district A, 35% in district B, and 61% in district C. Surgical procedures were classified retrospectively according to the likely risk (none, possible, or high) of exposure to the doctor's blood and, therefore, risk of HIV transmission. One hundred and ninety-five of those tested had undergone a procedure that carried a high risk of exposure; 179 had undergone a procedure thought to carry no risk. Patients in districts A and C who had undergone a procedure that carried a high risk of exposure were more likely to be tested than those who had not; 206 patients overall had undergone procedures that carried a high risk of exposure but were not subsequently tested.(ABSTRACT TRUNCATED AT 250 WORDS)
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7787919
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Sudden death in athletes.
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HCM, as well as coronary and myocardial structural abnormalities, is the most common pathology leading to SCD in young athletes. Furthermore, SCD from fatal arrhythmia seems to be the most common mechanism of death. In this population, however, data are insufficient to support either invasive or noninvasive approaches to clarify risk stratification for SCD. Because of the large population, variants of normal found within the athletic population, and the rarity of the disease, screening for individuals at risk is neither practical nor cost-effective. Not all athletes with HCM are at the same risk for SCD; a thorough history and physical examination should alert the health professional to potential risk factors. Efforts are under way to stratify athletes at risk for SCD to determine who can participate in competitive sports and who should not. However, until research can accurately define variables of hemodynamic and electrical instability that permit reliable identification of athletes with HCM who are at risk for SCD, the recommendation is to disqualify athletes with confirmed HCM from moderate- to high-intensity competitive sports. This recommendation includes athletes with or without symptoms or left ventricular outflow obstruction. Due to the decreased risk of SCD in older athletes, individual judgment of eligibility may be used. Athletes thought to have had myocarditis should be withdrawn from all competitive sports for a convalescent period of approximately 6 months, with thorough cardiac assessment and testing performed before returning to training. Athletes with atrial or ventricular tachyarrhythmia must be screened for structural abnormality, heart response during exercise, and the frequency and duration of the arrhythmia.(ABSTRACT TRUNCATED AT 250 WORDS)
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7787918
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Psychophysiologic responses of mechanically ventilated patients to music: a pilot study.
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Although mechanically ventilated patients experience numerous stressors, they have not been included in music therapy stress reduction and relaxation studies. To examine selected psychophysiologic responses of mechanically ventilated patients to music. A two-group experimental design with pretest, posttest, and repeated measures was used. Twenty mechanically ventilated patients were randomized to a music-listening group or a nonmusic (headphones only) group. Physiologic dependent measures--heart rate and rhythm, respiratory rate, systolic and diastolic blood pressure, oxygen saturation, and airway pressure--were collected at timed intervals. Psychologic data were collected before and after intervention using the Profile of Mood States. Using repeated measures analysis of variance, results for heart rate and respiratory rate over time and over time between groups were significant. Between-group differences were significant for respiratory rate. Significant differences were found via t test for the music group's Profile of Mood States scores. No adverse cardiovascular responses were noted for either group. Data indicated that music listening decreased heart rate, respiratory rate, and Profile of Mood States scores, indicating relaxation and mood improvement.
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7787917
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The unconscious experience.
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Although considerable research has been done on pathophysiology, metabolic and physical causes, and prognostic indicators, little is known about unconsciousness or coma from the perspective of the patient. To describe the experiences of patients who were once documented as being unconscious. Phenomenologic interviews were conducted with 100 patients whose records indicated that they had been unconscious during hospitalization. Interviews were also attempted with primary family members, significant others, or other external observers. Chart audits documenting the unconscious episode, medications, and diagnoses were also carried out. Data were compared, using van Kaam's method, and contrasted. Patients experienced one or more of five states: unconsciousness, inner consciousness, perceived unconsciousness, distorted consciousness, and paranormal experiences. They described hearing, understanding, and responding emotionally to what was being said when it was assumed they were not aware. In addition, 23 subjects reported near-death experiences or visits, out-of-body experiences, or some other paranormal experience. Patients' unconscious experiences can cause long-term effects. Patients often need reassurance that other patients subjected to similar conditions also have these experiences.
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7787916
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A randomized clinical trial of the effect of bed position after PTCA.
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After percutaneous transluminal coronary angioplasty, prolonged supine bedrest with the bed flat frequently causes back pain. This study was conducted to examine whether percutaneous transluminal coronary angioplasty patients could adjust their bed position to make themselves comfortable without increasing the frequency or severity of bleeding complications. To determine whether the risk of bleeding increased in patients who were allowed to use their bed controls to make themselves comfortable, and if the difference in comfort was significant between patients who controlled and elevated their bed position and patients who remained flat in bed. A randomized clinical trial was conducted; 54 patients undergoing percutaneous transluminal coronary angioplasty were randomly assigned to either the control group, in which patients remained flat in bed, or the experimental group, in which they controlled their bed position. Outcome measures included amount of bleeding at the catheter sites and patient comfort. No difference in the amount of bleeding at catheter insertion sites was found between the two groups. Few subjects reported pain at any time. Back pain at dinner and bedtime was higher in the control group, but only the bedtime difference was statistically significant. We conclude that patients may be allowed to adjust their bed position to 30 degrees for comfort without incurring increased risk of catheter entry site bleeding and that requiring patients to remain flat in bed has no scientific basis.
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7787915
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Postoperative circadian rhythms and cortisol stress response to two types of cardiac surgery.
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Although endocrine stress responses of coronary artery bypass patients have been reported, similar studies have not been conducted in patients undergoing implantation of an automatic cardioverter/defibrillator device. To compare patterns and magnitudes of intra- and postoperative cortisol stress responses in patients undergoing two types of surgery; rate at which postoperative cortisol levels return to presurgical levels; and whether stressors associated with these two procedures affect postoperative circadian rhythms of cortisol, heart rate, and body temperature. A time-series, small-group design was used to investigate 16 coronary artery bypass graft and 9 automatic cardioverter defibrillator patients. For the cortisol stress study, blood samples were obtained pre-, intra-, and postoperatively until day 6. For the circadian rhythm aspect, cortisol circadian rhythm aspect, cortisol levels, heart rate, and oral temperatures were measured every 2 hours for 24 hours beginning on postoperative day 1. Plasma cortisol levels increased significantly toward the latter part of surgery. Generally, no significant group differences were found in cortisol magnitude during and after surgery. Postoperative cortisol levels were significantly elevated from preoperative levels for both groups; however, the automatic cardioverter defibrillator group's cortisol levels declined at a slower rate. The stressors associated with these surgeries were sufficient to disrupt or abolish circadian rhythms for the measured variables. The elevated postoperative cortisol levels and altered circadian rhythms may contribute to increased vulnerability by dampening patients' anti-inflammatory and immunologic responses and adversely affecting their sense of well-being. The clinical significance of these findings is yet to be determined; more research is warranted.
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7787914
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Infectious complications associated with ventricular assist devices.
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Improvements in technology, patient selection, and patient management have led to a wider clinical application of mechanical circulatory support. Critically ill patients often develop multiorgan ischemia and are prone to multiple complications. Despite these advances, infection is a common and sometimes lethal complication of support with ventricular assist devices. This article provides guidelines for the prevention and management of infection in patients who require such support.
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7787913
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Comparison of nasogastric tube securing methods and tube types in medical intensive care patients.
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Nasogastric tube displacement can result in serious complications such as aspiration and inadvertent migration of the tube into the lungs. Replacement of the tubes is costly, time- and effort-intensive, uncomfortable for the patients, and potentially dangerous. To determine the best of three methods for securing nasogastric tubes in a medical intensive care population and to identify variables related to the failure of tube securing methods. A convenience sample of 103 patients requiring duodenal or standard gastric tubes for feeding, medication delivery, or decompression were randomly assigned to one of three taping methods: pink tape, clear tape, or "butterfly," for a total of 264 taping episodes. Data collection included the mean time until failure of the securing methods as well as variables such as patient alertness and mobility. The mean time until failure was 100 hours with pink tape versus 56 hours with clear tape and 30 hours with the "butterfly." Differences were significant. Duodenal tubes stayed secured longer than standard sump tubes (mean time until failure was 86 vs 41 hours) for all taping methods, but not significant relationship was demonstrated between mean time until failure and variables such as alertness, sedation, confusion, mobility, and the use of restraints. Our results showed that the pink tape method was superior. Nasogastric tube securing methods in adult critical care patients vary in efficacy and should be selected carefully.
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7787912
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Effect of a standardized rewarming protocol and acetaminophen on core temperature after coronary artery bypass.
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Cardiac surgical patients who require hypothermic cardiopulmonary bypass experience hypothermia, normothermia, and hyperthermia during the early postoperative period. Research-based rewarming protocols are needed to manage temperature variations. To describe the effect of a standardized rewarming protocol and acetaminophen on the following outcome variables: core temperature, peak core temperature, rewarming time, and hyperthermia. Patients (N = 60) were rewarmed using a standardized rewarming protocol. Electric heating blankets were used for subjects with core temperatures less than 36 degrees C on admission to the intensive care unit; other subjects were covered with cotton bath blankets. Subjects were also assigned to one of three acetaminophen groups (650 mg at 38.1 degrees C, 650 mg at 37 degrees C, 1300 mg at 37 degrees C). Using the protocol, subjects warmed to normothermia in 3.6 to 6 hours. The 16-hour core temperature thermal curves of heating blanket versus cotton bath blanket subjects differed significantly; thermal curves of the acetaminophen groups were similar. Peak core temperature was significantly lower in heating blanket subjects and unaffected by acetaminophen group. The onset of hyperthermia was not significantly affected by the method of rewarming (electric heating blanket versus cotton blankets) or acetaminophen group. Rewarming time was significantly longer for electric heating blanket subjects. Our results indicate that mildly hypothermic subjects rewarmed with electric heating blankets during the early postoperative period have lower peak core temperatures and longer rewarming times than those rewarmed with cotton bath blankets. Acetaminophen administration at normothermia does not significantly affect peak core temperature or the onset of hyperthermia.
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7787911
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Acute care nurse practitioner curriculum: content and development process.
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Curriculum development for preparation of acute care nurse practitioners requires a comprehensive process. To develop a program for their preparation at a large university, the faculty examined needs of the target patient population and care delivery system; scope of acute care nurse practitioner practice; current guidelines for the education of primary care nurse practitioners; evolving guidelines for the didactic and clinical education of acute care nurse practitioners; educational requirements of governing or licensing and certifying bodies; and placement of this new role within the existing healthcare team structure. A curriculum was then developed using a collaborative, multidisciplinary approach.
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7787888
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Position and orientation independent transactivation by c-Myc.
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The c-myc oncogene c-Myc is commonly activated in cancer and transactivates gene expression by binding to CACGTG DNA sequences as a heterodimeric complex with Max. The ornithine decarboxylase (ODC), p53, prothymosin alpha and ECA39 promoters are transactivated by c-Myc, and are considered direct targets, as activation is mediated by CACGTG sequences. Interestingly, the c-Myc-responsive CACGTG sequences in the p53, prothymosin alpha, ECA39 and murine ODC genes are all downstream of the RNA CAP site, suggesting that downstream sequences are preferred c-Myc targets. Using a series of heterologous reporter constructs, we have tested the effects of position and orientation of c-Myc-responsive CACGTG sequences on c-Myc's ability to activate transcription. A single binding site conferred c-Myc-responsiveness independent of position and orientation, and over distances of 1.7 kbp. The extent of transactivation was not significantly influenced by position of the responsive elements. By contrast, the extent of transactivation was dependent upon the number of c-Myc binding sites. The results demonstrate that c-Myc activates transcription independent of position and orientation and that considerable flexibility exists in the interaction of c-Myc transactivation domains with the general transcription machinery.
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7787887
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Cloning of the chandipura virus phosphoprotein encoding gene and its expression in Escherichia coli.
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Chandipura (CHP) virus, a member of the vesiculovirus genus within the Rhabdoviridae family, was first isolated from human patients in India. The full length phosphoprotein P gene of CHP have been cloned and expressed in Escherichia coli using the T7 polymerase-based pET-3 series of expression vectors. Under optimal conditions of induction with IPTG, the recombinant P protein constituted 35% of the total bacterial protein. The bacterially expressed protein was found to be phosphate-free. Deletion analysis suggested that the anomalous mobility of the P protein was due to its high acidity. The expressed protein can be phosphorylated in vitro by the extracts prepared from baby hamster kidney cells or rabbit reticulocytes. The cellular kinase involved in phosphorylation appears to be casein kinase II.
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7787886
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Dinucleotide repeat polymorphisms at nine loci in sporadic colorectal cancer.
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Genomic instability in the form of microsatellite alterations at nine loci on chromosomes 2p, 8p, 10p, 11p, and nm23-H1 locus on 17q21.3 were studied in sporadic colorectal tumors. Alterations in dinucleotide repeats in tumor DNA as larger allele, smaller allele, or loss of heterozygosity (LOH) were observed. Forty percent of tumor showed an RER+ phenotype. A significantly high number of alterations was detected at loci of chromosome 8p. The markers on chromosomes 2p, 10p, and 11p did not show such significant alteration. LOH was found to be associated with the nm23-H1 locus. No correlation was found between the age, site of tumor occurrence, or metastasis and the microsatellite instability.
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7787885
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Characterization of the interactions between double-stranded RNA and the double-stranded RNA binding domain of the interferon induced protein kinase.
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The interferon-inducible protein kinase, PKR, requires double-stranded (ds) RNA for its activation. We have previously mapped its dsRNA-binding domain (DRBD) to the amino terminal 170 residues (Patel and Sen, 1992). In the present study, we have characterized in detail the interactions between dsRNA and DRBD. For this purpose, DRBD was produced in bacteria as a polyhistidine-tagged protein and purified by affinity chromatography. A polyclonal antibody was raised against purified DRBD. For studying dsRNA-DRBD interactions, a Northwestern assay and an electrophoretic mobility shift assay (EMSA) using a radiolabeled in vitro transcribed 82 bp dsRNA probe was developed. The antiserum reacted with both DRBD and PKR but did not prevent their interactions with dsRNA. DRBD, on the other hand, blocked the activation of PKR by dsRNA. DRBD and the dsRNA probe formed multimeric complexes which were separable by EMSA. The antibody could interact with these complexes and supershift their mobility. Competition with unlabeled dsRNA revealed that the dimeric DRBD-dsRNA complex was much more stable than the monomeric complex. Similar competition assays using 11 different synthetic and natural RNA molecules revealed that only authentic dsRNA molecules could effectively compete with the probe for binding DRBD in a sequence-independent fashion.
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7787884
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Emergence of antigenic variants of simian immunodeficiency virus (SIVmac) in a seronegative macaque after SIVmac239 infection.
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Infection with the macaque strain of the simian immunodeficiency virus (SIVmac) induces simian immunodeficiency syndrome in rhesus macaques. This report describes the isolation and identification of antigenic variants of SIVmac in one of the infected monkeys (macaque #22803). Eight naive rhesus monkeys were inoculated with a titered viral stock of the molecularly cloned SIVmac239. Standard serological analysis revealed that all but two were seroconverted. Western blot analysis confirmed the seronegativity of macaque #22803. In addition, sera recovered from this monkey were not able to neutralize the parent SIVmac239. However, virus could be isolated from all of the infected animals, including macaque #22803. Sera recovered were reactive to the autologous virus. The results suggest that the virus from macaque #22803 may have undergone extensive antigenic shift in vivo. To test this hypothesis, a portion of the gag gene was amplified by the polymerase chain reaction (PCR), cloned, and sequenced. Sequence analysis revealed amino acid changes that were clustered between amino acids 200-245. Evaluation of the possible selective pressures contributing to the observed viral mutation revealed that in comparison with the other SIVmac239-infected monkeys, macaque #22803 produced an unusually high T cell proliferative response toward mitogen stimulation before infection, and continued to display a persistently high plasma viremia titer after infection.
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7787883
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TGF-beta 1 augments expression of the TIS10/prostaglandin synthase-2 gene in intestinal epithelial cells.
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Treatment of nontransformed rat intestinal crypt epithelial IEC-6 cells with tetradecanoyl phorbol acetate (TPA) + calcium ionophore (A23187) induces both the synthesis of prostacyclin and the expression of the TIS10/PGS-2 gene, a primary response gene encoding a second form of prostaglandin synthase (PGS). In addition to pharmacological induction by TPA + A23187, TIS10/PGS-2 message is also induced by the inflammatory cytokine interleukin 1-beta (IL-1 beta). Transforming growth factor beta 1 (TGF-beta), a potent cytokine known to modulate a variety of biological responses, does not by itself induce either prostanoid accumulation or TIS10/PGS-2 gene expression. TGF-beta does, however, augment both induced prostacyclin accumulation and the induced synthesis and accumulation of TIS10/PGS-2 protein and message in IEC-6 cells. TGF-beta concentrations in the range of 0.1-1.0 ng/ml (4.0-40 pM) maximally augment accumulation of TIS10/PGS-2 message. In contrast, dexamethasone attenuates prostacyclin production, TIS10/PGS-2 protein accumulation, and TIS10/PGS-2 message induction in IEC-6 cells. These results suggest that steroids and cytokines such as TGF-beta may (i) modulate intestinal epithelial cell growth and differentiation and (ii) influence gastrointestinal diseases such as gastric ulcers and colon cancer by modulating eicosanoid production.
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7787882
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In vivo binding of proteins to stably integrated MMTV DNA in murine cell lines: occupancy of NFI and OTF1 binding sites in the absence and presence of glucocorticoids.
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Activation of expression at the mouse mammary tumor virus (MMTV) promoter is thought to be controlled by nucleosome positioning. On stably integrated MMTV DNA, the long terminal repeat (LTR) region is organized in a phased array of nucleosomes which allegedly occludes transcription factors such as NFI from binding. NFI only binds to the promoter region when the ordered nucleosome structure is apparently disrupted by activated steroid hormone receptors in hormone induced transcription. In certain cell lines, binding sites for the transcription factors NFI and OTF1 are however required for hormone-independent expression of MMTV. We have used stably transfected mouse NIH3T3 and GR cells that exhibit detectable MMTV expression in the absence of hormone for in vivo determination of proteins binding to the MMTV promoter. Here, we present in vivo dimethyl sulfate footprinting data that show that the NFI and OTF binding sites are permanently occupied in vivo in these cells. The contacting guanine residues identified in vivo were demonstrated in in vitro methylation interference assays to correspond to binding by NFI and OTF1. These results demonstrate a novel feature of transcription factor occupancy at the MMTV LTR promoter.
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7787881
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Translational regulation of the mammalian growth-related protein P23: involvement of eIF-4E.
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Synthesis of the mammalian growth-related protein P23 is rapidly induced after serum stimulation of mouse fibroblasts and Ehrlich ascites tumour cells. This induction occurs at the translational level. Growth-induction leads also to an increase in phosphorylation of the rate-limiting initiation factor eIF-4E. Here, we present the following evidence indicating the involvement of eIF-4E in the regulation of P23 synthesis: 1) P23 synthesis is induced by the same mitogenic stimuli which lead to enhanced eIF-4E phosphorylation. 2) Upon heat shock treatment of Ehrlich ascites cells (which results in immediate dephosphorylation and concomitant inactivation of eIF-4E), P23 synthesis is rapidly shut off. 3) In control NIH 3T3 cells, P23 synthesis is readily induced by growth stimulation. This response is strongly diminished in cells overexpressing eIF-4E, and the basal level of P23 synthesis is elevated in these cells. Overexpression of a nonfunctional mutant of eIF-4E diminishes the basal level of P23 synthesis as well as the serum-response of the cells with respect to P23 induction. 4) Cells transformed by overexpression of the ras or src genes in which eIF-4E is highly phosphorylated do not show any inducibility of P23 synthesis. 5) HeLa cells expressing antisense RNA of eIF-4E, have reduced levels of eIF-4E/F and show reduced rates of growth and protein synthesis. In these cells the total amount of P23 protein is about 50% compared with control cells. The results suggest that P23 is one of the gene products, the synthesis of which is regulated by eIF-4E activity.
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7787880
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Identification of a rat protein tyrosine phosphatase gene preferentially expressed in the embryonal brain.
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We have identified a novel protein tyrosine phosphatase gene from an embryonal rat brain by reverse transcription-based polymerase chain reaction. Its transcription is specific to brain and is developmentally regulated, as it is expressed at high levels in embryonal and neonatal stages but scarcely in an adult. Southern blot analysis indicates that the gene exists as a single copy and is conserved among various species. Homology search of the deduced amino acid sequence suggests that this gene belongs to the same family of the membrane-type tyrosine phosphatase gene of Drosophila (DPTP10D), whose expression is specific to an central nervous system of fly embryo.
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7787879
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The tyrosinase gene family--interactions of melanogenic proteins to regulate melanogenesis.
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Several genes critical to the regulation of melanin production in mammals have recently been cloned and characterized. They map to the albino, brown, and slaty loci in mice, and encode proteins with similar structures and features, but with distinct catalytic capacities. The albino locus encodes tyrosinase, an enzyme with three distinct melanogenic functions, the brown locus encodes TRP1 (tyrosinase-related protein-1), and the slaty locus encodes TRP2, another tyrosinase related-protein. TRP2 functions as DOPAchrome tautomerase, an enzyme that preserves the carboxylic acid content of melanins, which would be spontaneously lost in its absence, while TRP1 is able to oxidize the DHICA produced by TRP2. In this study we have used three different systems (immune-affinity purified melanogenic enzymes, mutant melanocytes, and transfected cells) to examine the enzymatic interactions of these proteins, and their stabilization in a complex which significantly increases their physiological half-life. When extrapolated to the melanocyte, our results demonstrate the catalytic functions of these proteins and suggest how they might stably interact within a melanogenic complex in the melanosome to regulate the quantity and quality of melanin synthesized.
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7787878
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Apoptosis and the cell cycle.
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This brief review examines the strict relationships between cell apoptosis and G1 cyclins. It has been shown that the basic role of G1 cyclins is in regulating G1 progression and G1/S transition (the critical cycle point for cell program decisions, including apoptosis) a fatal program for cells unable to bypass G1/S checkpoint 1. Notably, both of the two giant regulators of checkpoint 1 (i.e., p105RB [retinoblastoma oncosuppressor-encoded protein] and p53 dependent WAF1/CIP1) are influenced by or influence G1 cyclins: cyclin E/cdk2 kinase complexes hyperphosphorylate p105RB, induce E2F release, and free G1 exit. On the other hand, p21-WAF1/CIP1 is an inhibitor of cyclin-dependent kinases blocking cells at G1/S. Thus, G1 cyclin activity appears as a conditio sine qua non for G1 exit and apoptosis escape.
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7787872
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[Transduodenal endoscopic drainage of pancreatic pseudocysts and peripancreatic collection].
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Until recently, the treatment of pancreatic pseudocysts was mainly surgical. However, two non-surgical invasive approaches are now possible: percutaneous aspiration under ultrasonic or CT monitoring and endoscopic drainage. PURPOSE--To report the result obtained using endoscopic drainage of pancreatic pseudocysts. METHODS--11 consecutive patients admitted with pancreatic pseudocyst had chronic pancreatitis and 1 patient had a well defined paraduodenal collection originated from acute necrotising pancreatitis. Endoscopic cystoduodenostomy was performed in the area of close contact with the digestive wall. A standard Olympus duodenoscope was used to reach the bulging wall and to allow the diatermic fistula. RESULTS--The success rate was 91.7%. Hemorrhage occurred in 1 patient (8.3%) controlled without blood transfusion. Endoscopic cystoduodenostomy was the definitive treatment in 10 patients 36 months after the procedure. One patient underwent gastrojejunostomy after 14 months for duodenal obstruction following relapsing pancreatitis. There was no relapsing cyst. There was no death following the endoscopic procedure. CONCLUSION--the endoscopic cystoduodenostomy constitutes an alternative procedure for the drainage of paraduodenal pseudocysts whenever restricted to the precise morphological indication of paraintestinal pseudocyst bulging into the duodenal lumen.
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7787874
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[Deprofessionalization or reprofessionalization: a study comparing law and medicine].
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The author discusses and compares the transformations in the profession of lawyers in the United States of America and the doctors in Brazil according to a theoretical analysis based upon the classical theory of the Sociology of the Professions. The discussion about the deprofessionalization of Medicine is conducted along some of the characteristics outlined by the theory. The author concludes that the challenge that faces medicine is a kind of re-organization that will change necessarily the profession as we know it today, but this change will not affect the professional autonomy or any other of its essential characteristics.
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7787873
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[Indications of exploration and repair of the orbital floor in fractures of the maxillozygomatic complex].
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Patients with orbital fractures may develop late complications like enophthalmos, orbital dystopia or diplopia, as a result of untreated orbital floor lesions, with herniation of orbital fat. Clinical and radiological findings are not enough for diagnostic and indication of orbital floor repair. To evaluate the indication of repair of the orbital floor, during the surgical treatment of maxillozygomatic or zygomatic-maxillary compound fractures, by means of systemic exploration and to compare clinical with surgical findings. 112 patients with unilateral zygomatic-maxillary compound fracture were submitted to exploration of the orbital floor, during the surgical treatment of the fracture. Open reduction and rigid internal fixation was performed with steel wire or miniplates. An autogenous conchal cartilage graft was used to repair the floor lesion, when there was bone loss of the inferior orbital wall and periorbita discontinuity, with fat herniation. The repair of the orbital floor was indicated in 46.4% of the patients. Early diplopia (before surgery) was observed in 26.6% and enophthalmos in 3.30% of the cases. Among patients with early diplopia, 60% needed repair, while 36.6% of the patients without early diplopia received cartilage graft. No important complications was observed. Orbital floor exploration is a complementary maneuver for the treatment of zygomatic-maxillary compound fractures that permits the precise diagnostic of the lesion and the correct indication of repair.
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7787871
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[Leprosy and pregnancy].
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We followed 20 cases of pregnant women with leprosy: eight lepromatous (L), seven "borderline", four turbeculoid and only one indeterminate (I) and their newborns. Three patients showed the first symptoms during pregnancy and another one in postpartum. One patient was sick during sixteen years and another one was treated during fourteen years. The bacterioscopic examination was positive in thirteen and negative in seven patients. The Mitsuda test was negative in sixteen, positive in two and in two others was not performed. The treatment in fourteen patients was polychimiotherapy (diamino diphenylsulfone, rifampicin and clofazimine). Three patients received dapsone monotherapy. Three women started the treatment postpartum. Reactions states were treated with corticosteroids and acetylsalicylic acid. The therapy was Irregular in nine and Regular in eight cases. Ten patients showed reactions: eight during pregnancy, one in puerperium and one in the lactation period. Eight showed erythema nodosum leprosum and two reversal reaction. One patient showed false positive biologic test for syphilis and another one had positive bacterioscopic examination in the lactation period. One patient showed false positive biologic test for syphilis and another had positive bacterioscopic examination in the lactation period. One newborn showed exfoliative dermatitis in the first hours of life and his mother had used sulfone during pregnancy. Among the twenty babies five had less than 2,500g in weight and four were premature. The reaction states of patients and low birth weight of premature babies occurred in lepromatous and "borderline" cases.
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7787870
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[Microneurography: technique to study cardiovascular regulation by the sympathetic nervous system in humans].
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Microneurography is a valuable and safe method for direct intraneural recording of sympathetic nerve activity to muscle and skin in humans. The technique and its application for the study of autonomic function will be briefly discussed. The regulation of muscle sympathetic nerve activity will be focused in different clinical situations and or stimuli, such as: essential hypertension, mineralocorticoid induced hypertension, exercise mental arithmetic stress, cold pressor test, hyperinsulinemia, oral alcohol ingestion.
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7787869
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[Practicability of cataract surgery at university hospitals: searching for an economic model].
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Resources available for health care all over the world are not enough to cover all the demand in this sector. Cataract Free Zones conducted in many regions of the country show that only 10% to 20% of blind patients caused by senile cataract can get operated on. To demonstrate feasibility of a model for cataract surgery with intraocular lens implantation at the Clinical Hospital from the University of Campinas, Unicamp, São Paulo, when considering the remuneration payed by the government for universitary services. Costs with disposable material were collected for extracapsular cataract surgery, with posterior intraocular lens implant, at the Clinical Hospital, Unicamp. The model includes outpatient surgery under local anesthesia, and costs rationalization in acquisition and wear of material. University Hospitals have a different situation in the health system, where fixed costs and part of the variable costs of cataract surgery are subsidized by the State government. Cataract surgery performed under the proposed methodology is economically feasible, considering disposable components only, and the price achieved was US$ 77 with government payment of US$ 474. More surgical interventions increases the efficiency of the institution, provides more surgical training to residents and better community health care. The authors consider that it is an obligation of University Hospitals, regard their commitment with training, research and quality of eye care deliverance, to increase the number of cataract surgeries for the lowest possible price.
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7787868
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Anatomical terms of Yanomani Indians translated into Portuguese and English.
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The authors translated into Portuguese and English the basic anatomical terminology used by the Yanomani indians. The knowledge of the names of organs and other parts of the human body and of a few having a clinical meaning should help those interested in the study of and in interaction with the Yanomanis.
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7787867
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[Serum beta 2 microglobulin (beta 2M) following renal transplantation].
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Although there was an important improvement in graft and patient survival the last 10 years, graft rejection continues to be a major barrier to the success of renal transplantation. Identification of a laboratory test that could help to diagnose graft rejection would facilitate the management of renal transplanted patients. PURPOSE--To evaluate the utility of monitoring serum beta 2M in recently transplanted patients. METHODS--We daily determined serum beta 2M levels in 20 receptors of renal grafts (10 from living related and 10 from cadaveric donors) and compared them to their clinical and laboratory evolution. RESULTS--Eight patients who presented immediate good renal function following grafting and did not have rejection had a mean serum beta 2M of 3.7 mg/L on the 4th day post transplant. The sensitivity of the test for the diagnosis of acute rejection was 87.5%, but the specificity was only 46%. Patients who presented acute tubular necrosis (ATN) without rejection had a progressive decrease in their serum levels of beta 2M, while their serum creatinine changed as they were dialyzed. In contrast, patients with ATN and concomitance of acute rejection or CSA nephrotoxicity presented elevated beta 2M and creatinine serum levels. CONCLUSION--Daily monitoring of serum beta 2M does not improve the ability to diagnose acute rejection in patients with good renal function. However, serum beta 2M levels seemed to be useful in diagnosing acute rejection or CSA nephrotoxicity in patients with ATN.
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7787866
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[Pharmacokinetics of cyclosporine and its metabolites in patients undergoing kidney transplantation].
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Pharmacokinetics of cyclosporine shows high inter and intra-individual variability and changes in several parameters are often found after kidney transplantation. PURPOSE--Evaluate serial studies of the pharmacokinetics of cyclosporine and its metabolites in patients undergoing kidney transplantation. METHODS--The pharmacokinetics of cyclosporine and its metabolites were analyzed in 70 studies performed in 29 patients, 26 before and 44 after kidney transplantation. The blood cyclosporine concentration was determined in 17 samples obtained after is oral or intravenous administration, using radioimmunoassay with specific (RIE-MoSP) and nonspecific (RIE-MoNP) monoclonal antibodies. RESULTS--The values of area-under-the-time-concentration curve (AUC), bioavailability (F), peak concentration (Cmax) and the 12 and 24 trough levels (C12 and C24), determined with RIE-MoSP, were lower than that obtained with RIE-MoNP, and the clearance (CL) and the volume of distribution (Vd) were higher. The elimination half-lives (t1/2) for both methods were not different. The absorption followed a zero order kinetic, demonstrating an inverse correlation between cyclosporine dose (mg/kg) and AUC/dose (r = -0.55, RIE-MoSP and r = -0.42, RIE-MoNP). Bioavailability ranged between 18% and 68% (RIE-MoSP) and were overestimated when calculated using RIE-MoNP (38% to 100%) owing to extensive cyclosporine metabolization during the first passage through the intestine and the liver. The metabolic rate analyzed by the ratio of blood concentrations determined with RIE-MoNP and RIE-MoSP (NP/SP), increased during the first 12 hours after cyclosporine administration, and was higher after oral dosing. The hematocrit and the serum lipoproteins concentrations significantly correlated with several pharmacokinetics parameters, mainly when they were determined with RIE-MoSP. The correlation between one sample obtained at any time after cyclosporine administration and the AUC were unsatisfactory, even the trough levels of 12 and 24 hours. AUCs calculated with 3 selected samples chosen by multiple linear regression correlated with AUC calculated using 17 samples, with a determination coefficient higher than 0.95 (RIE-MoSP, r = 0.975; RIE-MoNP, r = 0.974). CONCLUSION--Among all the parameters calculated, parameters of total exposure to the drug (AUC, AUC/dose, Cssav) showed the best correlation with the dose of cyclosporine, hematocrit and serum lipoproteins concentration. The methodology simplification, reducing the number of samples to calculate AUC, could be a good strategy to apply routinely these parameters in clinical transplantation.
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7787865
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[Ophthalmological manifestations in AIDS: evaluation of 445 patients in one year].
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The authors prospectively evaluated 445 HIV positive patients for the presence of ophthalmological manifestations. PURPOSE--To evaluate patients HIV positive with or without AIDS and correlate the data with the ocular findings mentioned in the literature. METHODS--445 HIV positive patients (66% with AIDS) were evaluated in one year at the Paulista School of Medicine, São Paulo Hospital, Brazil. There was a predominance of males (87%) and homosexuals (58.2%). RESULTS--Of the 445 patients, 52% presented ocular findings secondary to HIV infection at the first examination. The diagnosis included: CMV retinitis (25%), ocular toxoplasmosis (8.5%), herpes retinitis (3.6%), papilledema (2.2%), optic atrophy (1.6%), phthisis bulbi (1.5%), multifocal choroiditis (1.2%), retinal hemorrhages (0.9%), syphilitic uveitis (0.6%) and central vein occlusion (0.2%). CONCLUSION--The incidence of ophthalmic manifestations of AIDS in Brazil is similar to that found in the international literature. We found though a higher incidence of ocular toxoplasmosis than that in other countries. No ocular pneumocystosis was presents in the population evaluated by us.
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7787864
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[Placenta: a barrier for renotrophic factor?].
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To evaluate if the renotrophic factor can pass through the placenta and act on the fetal kidney. Twenty pregnant rats were divided into 4 groups of 5 animals: 1-control; 2-sham operated animals; 3-right nephfrectomy; 4-right nephrectomy--left polar nephrectomy. All rats were operated on during the 14 or 15 day of pregnancy. Maternal weight, serum urea and creatinine, number of fetal rats, fetal body and renal weight; DNA, RNA, protein and the amount of water in fetal kidneys were evaluated. Fetal kidneys showed a fall in weight in groups 3 and 4. In these groups tissue water concentration was lesser than groups 1 and 2. Fetal kidneys amounts of DNA, RNA and protein were similar in all groups. This study suggest that renotrophin could be a multifactorial system that can cross the placenta. The fall in renal fetal weight following maternal nephrectomy was consequent to a lesser tissue water content. Hypoplasia or hypotrophy did not play a role in this event. However, the fall in fetal kidney water was independent of the amount of maternal renal tissue that was removed.
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7787863
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[Protective effects of glutamine and elemental diet in acute actinic enterocolitis: histological evaluation].
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Radiotherapy plays nowadays an important role in malignancies treatment. However, collateral effects and severe complications owing to cellular damage of peritumoral tissues may occur. Different nutritional resources have been recently indicated to achieve intestinal protection during cancer irradiation. PURPOSE--The aim of this study was to set the role of glutamine and elemental diets in acute actinic enteritis prevention. METHOD--Sixty-five adult male Wistar rats with average weight of 200g were maintained in individual metabolic cages; daily body weight and food ingestion were carefully monitored. The animals were randomized into three groups and fed isocaloric and isonitrogenous diets: 1) CRt-polymeric-casein diet; 2) GRt-polymeric-casein diet supplemented with 2% glutamine and 3) ERt-elemental diet supplemented with 2% glutamine. After an adaptation period (seven days), all rats received abdominal radiation in five daily doses of 300cGy. Four days after the rats were operated on to resect the small intestine and colon for histological evaluation. RESULTS--Small intestine histological data in ERt and GRt rats were better than CRt rats, by preserving mucosal cellularity and increasing mitosis number and villi length. Simultaneously, ERt group had greater number of rats with normal villus-crypt relation than CRt or GRt groups. Large intestine histological data showed that the average crypts length in ERt and GRt rats were greater than in CRt ones. CONCLUSION--Glutamine-supplemented polymeric or elemental diets given to rats before, during and after abdominal radiotherapy showed protective effects against radiation injury, by supporting mucosal structure and recovery.
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7787861
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[Echo-guided percutaneous treatment of intraprostatic cysts].
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Diagnostic and therapeutic values regarding echoguided percutaneous treatment of intraprostatic cysts are reviewed and discussed. Since 1987 we have detected by ultrasonography 48 intraprostatic cysts, 22 asymptomatic patients were evaluated periodically. A ultrasound guided percutaneous puncture was performed in 26 symptomatic patients. 10 patients affected by dysuria were treated by aspiration and injection of antibiotics. 14 oligospermic patients underwent cyst aspiration followed by introduction of sclerosing agents (aethoxysclerol or alcohol). In one communicating cyst simple aspiration has been performed. A giant cystoadenoma has been resolved by surgical procedure. In the follow-up (2 months - 6 years) we observed: 5 recurrences (50%) in the cysts treated with antibiotics and 6 (43%) recurrences in the cysts treated with sclerosing agents. However, 8 patients out of 10 obtained a resolution of the urinary symptoms and 8 patients out of 14 improved their seminal parameters. On our experience, percutaneous echoguided treatment of prostatic cysts is a suitable and safe technique because of the possibility to resolve some clinic problems, although an high recurrence rate.
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7787860
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[Transrectal echography in laser treatment of incidental prostatic carcinoma].
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This report is concerning on our experience in the management of the incidental prostatic cancer treated by laser irradiation and transrectal ultrasounds (TRUS). 22 patients, with stage A incidental prostatic cancer, underwent preliminary TRUS to evaluate suspected areas of residual tumor and/or the capsule thickness. 5 patients, before the laser irradiation, have been treated with 2nd look TURP because residual tumor or much residual prostatic tissue was present. Following TRUS evaluation all the patients underwent a laser irradiation with TRUS guidance. During the laser irradiation TRUS evaluation allows to recognize the anatomy of the prostatic capsule, the thickness of the capsule and to perform a safety and complete laser irradiation of the prostatic capsule with a depth laser irradiation. In the postoperative follow-up the TRUS demonstrated, in 18 patients, a complete laser induced fibrosis of the capsule. In conclusion the TRUS represents a good technique for pre and postoperative evaluation in the patients of stage A prostatic cancer treated with laser irradiation.
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7787858
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[Bladder hernia: a clinical case].
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The Authors report a case of inguinal bladder hernia and briefly refer about the different kinds of this rare pathology which is often associated to the commonest inguinal hernia. They, moreover, point out the surgical treatment which has to aim to the repositioning of the bladder and to solve the cervicovesical obstruction.
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7787859
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[Correlation between ultrasonography imaging and surgical findings in scrotal trauma].
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The Authors report their experience of 20 cases of scrotal trauma. The etiopathogenesis of lesions are stressed as well as the importance of an early diagnosis, in order to plan a correct treatment avoiding immunological and atrophic outcomes. All of the patients underwent a diagnostic ultrasonographic examination. Eighteen of them were surgically treated, whereas last two recovered by means of a week antibiotic and anti-inflammatory medical therapy. The scrotal sonography showed a 100% sensibility for testis injuries and a 80% specificity for albuginea fractures. In fact a fracture of the tunica albuginea was found in two cases although they showed a normal scrotal sonogram. It is worth of mention that in the authors' experience the ultrasonography generally understages the testis damages. Only the surgical exploration is believed to be able to make a sure diagnosis of type and seriousness of the scrotal injury.
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7787857
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[Prognostic predictive factors of the clinical response to immunotherapy with subcutaneous interleukin-2, in patients with metastatic renal carcinoma: analysis of 60 cases].
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The intravenous immunotherapy with high-dose interleukin-2 (IL-2) would constitute one of the most effective treatments of metastatic renal cell carcinoma (RCC). More recently, IL-2 subcutaneous therapy has also appeared active, either alone or in association with interferon, with results comparable to those found with the intravenous route of injection, but with a lower toxicity. On this basis, we have designed a protocol of treatment with low-dose IL-2 alone given subcutaneously as a first or a second line therapy in metastatic RCC. The study included 60 consecutive patients (pts) (M/F: 39/21, median age 56 years, range 26/74). IL-2 was given at a dose of 3 millions IU twice/day for 5 days/week, for 6 weeks, corresponding to one cycle. In non progressed pts a second cycle was repeated after a 28-day rest period. Dominant metastasis sites were, as follows: soft tissues: 8; bone: 11; lung: 29; liver: 3; liver plus lung: 7; adrenal: 2. The minimum follow-up was 18 months and the median follow-up was 34 months (range 18-48). A complete response (CR) was achieved in 2/60 (3%) pts. A partial response (PR) was obtained in 15/60 (25%). Therefore, tumor objective rate (CR + PR) was 17/60 (28%). The median duration of response was 13 months (4-33).(ABSTRACT TRUNCATED AT 250 WORDS)
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7787856
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[Lymphocyte levels before treatment with subcutaneous interleukin-2 and during maintenance treatment in relation to the clinical efficacy in metastatic renal carcinoma].
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the antitumor activity of IL-2 is mediated by an increase in lymphocyte number. Moreover, our previous studies have shown that therapy for 1 week/month with low-dose subcutaneous IL-2 is sufficient to maintain high levels of lymphocytes in cancer patients who have had tumor regression or stable disease (SD) in response to IL-2 immunotherapeutic cycles. This study was performed to establish whether tumor progression in cancer patients chronically treated with IL-2 may be associated with lymphocyte number decline. the study included 60 metastatic renal cell patients, who were treated with 2 induction cycles of IL-2 subcutaneous immunotherapy (6 million IU/day for 5 days/week for 6 weeks, corresponding to one cycle). Tumor regression occurred in 17/60 patients, 23 patients a SD, and the remaining 20 cases progressed. Non-progressed patients (n = 40) underwent a maintenance therapy consisting of one week of therapy every month. After a median follow-up of 18 months, 29/40 patients with response or SD had progressed. The immune investigation consisted of lymphocyte, T lymphocytes, NK cell number determination and sCD25 level detection. the mean number of lymphocytes, T lymphocytes and NK cells observed on IL-2 maintenance therapy was significantly higher than that seen before beginning the immunotherapy. Moreover, mean number of lymphocytes and mean levels of sCD25 observed at the time of tumor progression were respectively lower and higher than those seen on maintenance therapy in the same patients, without, however, significant differences. despite the importance of lymphocytes in mediating the antitumor activity of IL-2, this study shows that tumor progression in cancer patients chronically treated with low-dose IL-2 after response or SD during IL-2 induction cycles is not associated with a significant decline in lymphocyte, T lymphocyte or NK cell numbers. Further studies, carried out to analyze the functional status of immune cells at the time of tumor progression, will be necessary to define the role of immunity in cancer patients progressing under IL-2 chronic therapy.
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7787855
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[Abnormal production of oxygen free radicals by low leukocytospermia in purified fractions of semen from infertile patients].
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Seminal leucocytes (WBC) play an important role, whereas this is still unknown. Quantitative normal threshold-value for leucocytospermia (Ls) (WBC < or = 1 million/ml) seems not to be a safety predictive marker of male accessory gland infection (MAGI) and/or MAGI-related adverse effects on semen quality and/or fertility because several drawbacks: a) inadequate staining techniques are responsible of an underestimated WBC concentration in spermatic fractions (100%) obtained from high-density Percoli gradient (Pc 100%); b) Ls could be correlated far better to the clinical findings and/or outcomes if some biochemical data on L metabolism are also studied (Radical Oxygen Species-ROS-generation, phagocytosis, leucotoxins). In order to point out importance about an joint morphological/biochemical analysis about Ls, we recruited 76 selected infertile (from 2-7 yrs) patients (aged 32-45 yrs) who, in their 50% Percoli fractions, had previously produced WBC-ROS > 95th percentile values registered from our control group (n = 28, fertile men). In all infertile population we have analysed through Pc100 fraction either the percentage of WBC-negative patient's specimens (group A) and within WBC-positive ones if a significant difference was present in the maximal WBC-ROS production among different subgroups at WBC concentrations (group B:0.01-0.09, group C:1-10, group D: > 10 x 10(4) WBC/10(7) spermatozoa).(ABSTRACT TRUNCATED AT 250 WORDS)
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7787854
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[Our experience with the orthotopic continent colonic neobladder].
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In the last years particular surgery operations became refined for the techniques and therapeutics progresses also developed in this field. This has allowed with major security to accomplish engagemently reconstruction operations after removal of the bladder, especially for cases of neoplastic pathology, to offer the patients a more normal quality of life avoiding urinary derivations that should change the performance of "EGO". After the operations of radical cystoprostatovesciculectomy different methods have been presented for the construction of heterotopical and orthotopical neobladder; among these the continent colic orthotopical neovesica of Goldwassern which uses the detubulization right colon, in our opinion could offer best functional and clinic results in virtue of easier execution and to use of minor number of intestinal segments. Moreover, for the peculiar characteristics of colic segment, allow to make a wide tank at low pression with perfect diurnal and nocturnal continence. We have, therefore, presenting the results of our experience regarding 12 cases of continent colic orthotopical neovesica, by Goldwasser, with a follow-up of 1-6 years which have comforted us with the results predicted. Although other techniques may offer similar results we believe that the Goldwasser method is still valid for all the above reasons.
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7787850
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Energy expenditure of below-knee amputees during harness-supported treadmill ambulation.
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Traditional rehabilitation of amputees is primarily aimed at strengthening remaining musculature necessary for prosthetic use and gait training. Available gait training time, however, is often limited by pain, residual limb skin tolerance, and the patient's cardiovascular endurance. Harness-supported treadmill ambulation is a rehabilitation technique being used by physical therapists to decrease an individual's body weight by a given percentage during exercise. This, theoretically, allows an amputee to ambulate on a prosthesis at a lower energy cost. The purpose of this study was to compare the energy expenditure of healthy below-knee amputee volunteers with healthy able-bodied volunteers during harness-supported treadmill ambulation in order to determine if energy conservation is achieved. Subjects were tested on a treadmill, walking at .67 m/sec (1.5 mph) and 1.34 m/sec (3.0 mph) during each of the following randomized harness-supported treadmill ambulation situations: full body weight, 20% body weight supported, and 40% body weight supported. During the last minute of each trial, rate of perceived exertion, heart rate, and standardized indirect calorimetry oxygen consumption (VO2, ml/kg/min) measures were collected. Caloric expenditure (kl/min) was calculated using metabolic conversion equations. Peak heart rate, peak VO2, and peak kl/min were measured after the conclusion of the last walking trial by taking each subject to volitional fatigue. Data were analyzed for each harness-supported treadmill ambulation situation and group using analysis of variance (ANOVA). The researchers identified significantly lower ratings of perceived exertion, heart rates, and VO2s for able-bodied subjects vs. below-knee amputees for all trials. Both groups demonstrated significantly lower heart rates, VO2s, and kl/min at 1.34 m/sec with 40% body weight supported.(ABSTRACT TRUNCATED AT 250 WORDS)
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7787853
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Posture in patients with shoulder overuse injuries and healthy individuals.
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Assessment of posture is an integral component of patient evaluation with shoulder overuse injuries. However, the professional literature contains relatively few studies that have assessed the relationship between posture, function, and injury. The purpose of this study was to determine the relationship and differences in postural variables within and between subjects with overuse injuries to the shoulder of healthy subjects. Thirty patient subjects and 30 healthy subjects matched for age and gender were recruited. Scapular protraction and rotation, forward head position, midthoracic curvature, and passive humeral elevation in the plane of the scapula were measured randomly in standing. All measurement techniques were standardized and validated. Intrarater and interrater reliability for all clinical measures were established before data collection. Forward head position was significantly greater (p < .001) in the patient group than the healthy group; humeral elevation was significantly greater (p < .001) in the healthy group than in the patient group and in the uninvolved shoulders (p < .01) than the involved shoulders within the patient group. Scapular protraction, rotation, midthoracic curvature, and scapular symmetry were not significantly different between groups. Scapula protraction and rotation were significantly related (p < .05) in the patient group. No other postural variables were related. Conclusions regarding the influence of posture to shoulder injury are inconclusive based on several confounding variables that may have affected the outcome.
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7787852
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The effects of therapeutic application of heat or cold followed by static stretch on hamstring muscle length.
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Hamstring stretching is an important part of treatment programs aimed at decreasing the likelihood of hamstring injury. Few studies have examined the use of superficial thermal modalities in conjunction with hamstring stretching. The purpose of this study was to determine if the application of a superficial heating or cooling modality, followed by static stretch, increased the efficacy of static stretching of the hamstring muscles. This study examined 12 male and 12 female subjects, ages 18-38. All subjects received each of the following treatments: heat followed by static stretch, cold followed by static stretch, and static stretch alone. Each treatment was separated by at least 1 week. Pre- and post-treatment measurements of hamstring length were obtained using the Active-Knee-Extension (AKE) test. The data were analyzed via a 2 x 3 analysis of variance experimental design. Results indicated that there was an increase in hamstring length regardless of stretch treatment used, with F(1,23) = 35.49, p < .001. However, no significant differences were detected among stretch treatments, F < 1.0, nor among interaction effects, F < 1.0. The results of this study suggest that adequate hamstring stretching can occur without the use of a superficial thermal modality.
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7787851
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Patellofemoral joint compressive forces in forward and backward running.
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The use of backward running is becoming more common in the rehabilitation setting. In particular, backward running has been suggested as a treatment modality in patients experiencing patellofemoral pain syndrome. To date, no study has examined the loads at the patellofemoral joint during backward running. The purpose of this study was to compare patellofemoral joint compressive forces during forward and backward running. Ground reaction force and kinematic data were collected on five male joggers during free speed forward and backward running. A floor reaction force vector model was used to calculate the stance phase knee extension moments. The distance used for the extensor muscle lever arm was 4.9 cm. Patellar mechanism angle was calculated based on knee joint angle. There was a reduction in the peak patellofemoral joint compressive forces in backward compared with forward running (2277 +/- 192N vs. 4253 +/- 1292N; p < 0.05) at self-selected speeds. Peak patellofemoral joint compressive force occurred significantly later (p < 0.05) in the stance phase of backward running (52 +/- 4%) than in forward running (35 +/- 3%). The peak patellofemoral joint compressive force normalized to subject body weight was 5.6 +/- 1.3 body weight in forward running and 3.0 +/- 0.6 body weight in backward running. The results suggest that backward running at a self-selected speed may reduce patellofemoral joint compressive forces and, coupled with the quadriceps strengthening that has previously been reported, may be beneficial in the rehabilitation of patellofemoral pain syndrome in runners. However, constant speed comparisons or other models may yield different results.
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7787849
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The effect of two types of foot orthoses on rearfoot mechanics.
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Little experimental data exist regarding the comparative biomechanical of various foot orthoses. This study evaluated the comparative effect of biomechanical orthoses and over-the-counter arch supports on controlling rearfoot pronation. Twenty-four patients with forefoot varus deformity were studied while walking on a treadmill. Two-dimensional, videotape motion analysis was used for studying rearfoot mechanics with three experimental conditions: 1) shoes only, 2) shoes plus arch supports, and 3) shoes plus biomechanical orthoses. The variables studied were: maximum pronation, calcaneal eversion, maximum pronation velocity, time-to-maximum pronation, and total pronation. No difference was noted in maximum pronation, calcaneal eversion, and total pronation between the three conditions. The data for maximum pronation velocity and time-to-maximum pronation were not reliable. Based on the results of this study, padded arch supports nor biomechanical orthoses can be preferentially recommended for their ability to control maximum pronation, calcaneal eversion, and total pronation during walking. Additional research is necessary to: 1) identify the biomechanical effects that are responsible for the clinical success of foot orthoses, and 2) determine better designs for controlling rearfoot movement.
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7787848
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Proximal tibiofibular subluxation relationship to lateral knee pain: a review of proximal tibiofibular joint pathologies.
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Proximal tibiofibular subluxation is the symptomatic hypermobility of the proximal tibiofibular joint. Pain along the lateral aspect of the knee must be carefully evaluated as the anatomy and biomechanics of this region are very complex. Anatomical variants of the proximal tibiofibular joint may be key to understanding the pathomechanics and, thus, treatment of this joint. The "horizontal" proximal tibiofibular joint has a higher degree of mobility, while the "oblique" joint is relatively immobile to rotational forces on the fibula. Increased fibular external rotation will result in injury to the anterior capsule and ligaments of the proximal tibiofibular joint causing common complaints of "popping" and lateral knee pain. Treatment of proximal tibiofibular subluxation will involve modifications of a patient's activity level and training programs, utilization of a supportive strap, lower leg strengthening, and modifications in the lower kinetic chain biomechanics.
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7787847
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A Drosophila gene that encodes a member of the protein disulfide isomerase/phospholipase C-alpha family.
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Screening of a Drosophila genomic DNA library at reduced stringency hybridization conditions using a rat PLC alpha cDNA probe yielded a gene which encodes a member of the protein disulfide isomerase/PLC alpha family. The gene has been localized to band 74C on the left arm of the third chromosome and has been designated dpdi. Northern analysis shows that the dpdi gene encodes a transcript that is 2.3 kb in length and is present throughout development as well as in both heads and bodies of adults. The deduced dpdi protein is 496 amino acids in length and contains two domains exhibiting high similarity to thioredoxin, two regions that are similar to the hormone binding domain of human estrogen receptor, and a sequence of four amino acids (KDEL) at the C-terminus which has been described by others as being responsible for retention of proteins in the endoplasmic reticulum. Overall, dpdi contains a higher similarity to rat protein disulfide isomerase (53% identical) than to rat PLC alpha (30% identical). However, it is unclear whether dpdi functions in vivo as a PDI or as a PLC, or both. Drosophila, with its well characterized genetics and the ability to generate mutants in a gene that has been cloned, provides an excellent system in which to resolve this issue.
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7787846
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Phylogenetic position of yeast-like symbiotes of rice planthoppers based on partial 18S rDNA sequences.
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The rice planthoppers, Nilaparvata lugens, Sogatella furcifera, and Laodelphax striatellus, harbor intracellular yeast-like symbiotes (YLS) in the fat body. The YLS are obligated endosymbiotes and are transovarially inherited. Nucleotide sequences of the 18S rRNA genes from the YLS were analyzed by direct sequencing. The YLS of the three species of planthoppers were monophyletic and their taxonomic positions were in the class Pyrenomycetes in the subphylum Ascomycotina.
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7787843
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Characterization of Aphidius ervi (Hymenoptera, Braconidae) ribosomal genes and identification of site-specific insertion elements belonging to the non-LTR retrotransposon family.
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We performed a molecular analysis of the Aphidius ervi ribosomal gene structure. This insect belongs to a set of closely related Aphidiinae species of the genus Aphidius Nees, of relevant interest in biological control. We constructed A. ervi genomic libraries, cloned and characterized several rDNA repeating units and sequenced different regions of the rDNA cistrons. We have found that insertion sequences interrupt the A. ervi 28S rDNA genes: the sequences of the two 5' and 3' insertion-28S junctions show that the elements are present at the position where R1 elements have been found in various insect species. In addition, the insertion of the element produces a duplication of the 14 nt target region. The sequence analysis indicates that the A. ervi elements belong to the R1 retrotransposon family with a highly conserved reverse transcriptase domain.
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7787844
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Characterization of a salivary gland-specific esterase in the vector mosquito, Aedes aegypti.
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Esterase enzymatic activity was investigated in salivary gland lysates of adult Aedes aegypti. Esterases in lysates made from female glands had higher specific activity than those in lysates from male glands towards beta-naphthyl acetate but showed no difference with alpha-naphthyl butyrate as a substrate. Female salivary gland lysates showed no difference in activity to alpha- and beta-forms of naphthyl acetate and no discernable activity towards alpha-naphthyl caprate. Both female and male salivary gland lysates exhibited phosphatase enzymatic activity but the specific activities were lower than those seen for the esterase enzymatic activity. Salivary gland esterase activity was inhibited completely by paraoxon, para-hydroxymercurobenzoate, tetraethylammonium iodide and moderately by diisopropylfluorophosphate. Eserine and phenylmethylsulfonylfluoride had no effect on enzyme activity. In a probing assay, adults of both sexes were shown to secrete esterase in saliva. Esterase activity was present in the saliva of females probing for either a sugar meal or a blood meal. Furthermore, esterase was secreted from female salivary glands in culture. Histochemical analysis of dissected salivary glands showed that the majority of the esterase enzymatic activity was in the distal-lateral lobes of the female tissues, although the proximal-lateral and medial lobes also had activity. Male salivary glands stained uniformly over all of the lobes. A salivary gland-specific esterase, designated SG-EST, appears to account for the majority of enzyme activity in the glands. SG-EST was partially purified by electroelution of an active protein from native polyacrylamide gels, and has an approximate molecular weight of 65,000 Da. In separate experiments, affinity chromatography independently identified a single 65,000 Da protein likely to be SG-EST. Native electrophoretic analysis of salivary glands revealed that, while most enzyme activity is due to SG-EST, there are two other esterases present. One of these minor moieties is present in adult tissues in addition to the salivary gland, and the other is present throughout development. Possible functions of the salivary gland esterase are discussed.
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