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Biomedical subjects

L Simon

Publications and source records attributed to L Simon.

At least 19 recordsLinked to original sources
PubMed1999

B lymphocyte antigen D8/17 and repetitive behaviors in autism.

OBJECTIVE: Monoclonal antibody D8/17 identifies a B lymphocyte antigen with expanded expression in rheumatic fever, Sydenham's chorea, and subgroups of obsessive-compulsive disorder and Tourette's syndrome with repetitive behaviors. The authors examined the rate of D8/17 expression in children with autism and its correlation with severity of repetitive behaviors. METHOD: Blood samples from 18 patients with autism and 14 comparable medically ill children were evaluated for percentage of D8/17-positive B cells by immunofluorescence and for streptococcal antibodies. Severity of repetitive behaviors was also determined. RESULTS: The frequency of individuals with > or =11% D8/17-positive cells was significantly higher in the autistic patients (78%) than the comparison subjects (21%), severity of repetitive behaviors significantly correlated with D8/17 expression, and D8/17-positive patients had significantly higher compulsion scores than D8/17-negative patients. CONCLUSIONS: D8/17 expression is high in patients with autism and may serve as a marker for compulsion severity within autism.

Adolescent↗
PubMed1999

Imaging in rheumatoid arthritis: results of group discussions.

None of the current scoring methods for radiological damage in rheumatoid arthritis (RA) is ideal. The objective for RA imaging at OMERACT IV was to start discussion about the problems and applicability of the current scoring methods for radiological damage and to start discussion on the challenge of new imaging techniques. The RA imaging module comprised preconference reading material, plenary sessions, small group discussions, and a plenary report of the group sessions, combined with interactive voting. The OMERACT filter guided the discussions. Priorities for further research in imaging studies were: (1) pathologies versus features on radiographs; (2) relation with longterm outcome; and (3) definition of minimum clinically important difference.

Arthritis, Rheumatoid↗
PubMed1999

Randomized clinical trials and longitudinal observational studies in systemic lupus erythematosus: consensus on a preliminary core set of outcome domains.

The OMERACT module on systemic lupus erythematosus (SLE) dealt with the definition of preliminary core sets of outcome domains for randomized clinical trials (RCT) and longitudinal observational studies (LOS). After lectures introducing the problems and addressing the key issues, 6 discussion groups, 3 each for LOS and RCT, discussed and weighted more than a dozen possible items for use as outcome domains. The means of the respective 3 groups were calculated. For both RCT and LOS the same outcome domains received more than 10 of a total maximum of 100 points: disease activity, health related quality of life (HRQOL), damage, and toxicity/adverse events. However, the weights for HRQOL and damage were different for LOS and RCT. A final vote led to the acceptance of these 4 variables as a preliminary core set for outcome in SLE by more than 80% of the participants. This core set will allow for improved design, performance, and evaluation of future studies in SLE. However, a number of domains not included in the core set were regarded as important for further analysis and research.

Decision Making↗
PubMed1998

Detection of adenovirus in the waters of the Seine River estuary by nested-PCR.

Several systems for isolating viruses from environmental samples have been tested. The most promising method is based on genomic amplification. The authors attempted to detect adenovirus in nucleic-acid extracts from the Seine River estuary by a two-step amplification of a 220-bp segment of the conserved coding region of type 2 adenovirus hexon protein L3. The primers used in this study detected the most prevalent adenovirus serotypes in human disease in France, but not other virus strains or bacteria. The sensitivity of the nested polymerase chain reaction (PCR) amplification was estimated to be 10(2) copies of the adenovirus target sequence per ml of Seine River water. Nucleic-acid extracts from Seine River estuary waters were analysed and some tested positive for the presence of adenoviruses.

Adenoviridae↗
PubMed1998

[Prolonged curarization with suxamethonium in a four-week old infant].

A case of a 28-day-old infant who developed suxamethonium apnoea is described. He was found to be homozygous for atypical cholinesterase. Main characteristics of this disorder are reviewed. Other causes of prolonged apnoea in infants recovering from anaesthesia for surgery of pyloric stenosis are discussed.

Apnea↗
PubMed1998

[Toward a medical approach to the evaluation of activity in a physician-staffed mobile intensive care unit].

OBJECTIVE: To test the ability of various medical criteria for classifying the patients in a physician-staffed mobile intensive care unit (MICU) by referring to intervention times. STUDY DESIGN: Prospective, open study. PATIENTS AND METHODS: For all the on-scene interventions of the MICUs over a 10-month period, the following data were prospectively collected: pre-hospital diagnosis, initial severity score, medical care score, immediate outcome and three intervention times: on-scene time (OS), time spent with the patient by the MICU team (MT), total duration of intervention (TD). RESULTS: A total of 3,672 MICU interventions were included. Median times were 45 min (32-59) for OS, 66 min (41-91) for MT and 85 min (61-116) for TD. The amount of interventions in a city was correlated with the population (R = 0.95; P < 0.001). The medical care score was greater than one in more than half of the patients. It defined five groups of patients which were different for the three intervention times (P < or = 0.001). A third of the patients were directly transported by the MICU to an ICU. For the median test, immediate outcome groups were different for the three intervention times (P < 0.001). After exclusion of patients with initial cardiac arrest, initial severity score defined five groups of patients which were different for the three intervention times (P < 0.002). Initial severity score and medical care score were correlated (R = 0.37; P < 0.001). CONCLUSION: A classification of the patients based on immediate outcome would be a more accurate indicator of the variability in medical care and consumption of resources in a physician-staffed MICU. In addition, a medical intervention score should be developed to better characterise this medical activity.

Adult↗
PubMed1998

Terror management and aggression: evidence that mortality salience motivates aggression against worldview-threatening others.

The hypothesis that mortality salience (MS) motivates aggression against worldview-threatening others was tested in 4 studies. In Study 1, the experimenters induced participants to write about either their own death or a control topic, presented them with a target who either disparaged their political views or did not, and gave them the opportunity to choose the amount of hot sauce the target would have to consume. As predicted, MS participants allocated a particularly large amount of hot sauce to the worldview-threatening target. In Studies 2 and 3, the authors found that following MS induction, the opportunity to express a negative attitude toward the critical target eliminated aggression and the opportunity to aggress against the target eliminated derogation. This suggests that derogation and aggression are two alternative modes of responding to MS that serve the same psychological function. Finally, Study 4 showed that MS did not encourage aggression against a person who allocated unpleasant juice to the participant, supporting the specificity of MS-induced aggression to worldview-threatening others.

Adult↗
PubMed1998

Acute pancreatitis after orthotopic liver transplantation in children: incidence, contributing factors, and outcome.

BACKGROUND: Acute pancreatitis after orthotopic liver transplantation is a well-known complication in adults that has never been described in children. In adults, end-stage liver disease related to hepatitis B, intraoperative pancreatic injury caused by extensive peripancreatic dissection, the type of biliary anastomosis performed, and numerous drugs, have all been described as predisposing factors in acute pancreatitis after liver transplantation. The current retrospective review was undertaken to identify the incidence, the contributing factors, and the outcome of acute pancreatitis after liver transplantation in children. METHODS: During a 10-year period, 375 children underwent 434 liver transplantations in the authors' institution. In seven patients (1.9%), clinical acute pancreatitis developed after orthotopic liver transplantation. Indication for initial liver transplantation was biliary atresia (n = 3), acute liver failure (n = 3), and type 1 Crigler-Najjar syndrome. In all seven patients, liver graft function was initially adequate. The diagnosis of acute pancreatitis was based on clinical, biochemical, ultrasonographic, and surgical signs. RESULTS: In six patients, acute pancreatitis appeared within the first week after transplantation. The diagnosis was confirmed by abdominal laparotomy in five children. In the current series, emergency liver transplantation (p < 0.001), retransplantations (p < 0.001), and infectious peritonitis (p < 0.001) were contributing factors. Despite supportive measures, three patients died (43%) because of multiple organ dysfunction syndrome. CONCLUSIONS: Acute pancreatitis is an uncommon but life-threatening complication after liver transplantation in children. Early diagnosis and aggressive treatment of infectious complications are major elements in the management of acute pancreatitis after liver transplantation.

Acute Disease↗
PubMed1998

Terror management and meaning: evidence that the opportunity to defend the worldview in response to mortality salience increases the meaningfulness of life in the mildly depressed.

Previous terror management research has demonstrated that mildly depressed participants show a greater increase in worldview defense in response to reminders of their mortality than do nondepressed participants. Because the cultural worldview is posited to provide a meaningful conception of life, we hypothesized that mildly depressed participants who defend their worldview in response to mortality salience (MS) would increase their perception that the world is meaningful. A preliminary study first examined the Kunzendorf No Meaning Scale as a measure to assess perceptions of meaning. In the primary study, mildly depressed and nondepressed participants contemplated their own mortality or a neutral topic, evaluated two targets in a manner that either allowed them to defend their worldview or that did not, and then completed the Kunzendorf No Meaning Scale. As predicted, mildly depressed participants who had the opportunity to defend their worldview in response to mortality salience reported greater meaning in life than did mildly depressed participants who did not have the opportunity to defend their worldview, or mildly depressed participants not exposed to mortality salience. Implications for understanding and treating depression are briefly discussed.

Adult↗
PubMed1998

Intestinal uptake of particulate material by dexamethasone-treated rats: use of a novel technique to avoid intestinal mucosal contamination.

The aim of this study was to investigate the effect of immune suppression on the uptake of particles across the wall of the intestine and the dissemination of the particles to systemic organs. Normal and dexamethasone-immunosuppressed rats were dosed orally with 0.5 mL distilled water or fluorescent polystyrene latex particle suspension containing 2.33 x 10(9) 2-microm diameter particles. One hour after particle dosing, the animals were killed by CO2 asphyxiation. The intestinal tissues and systemic organs were sampled for particle quantitation. To avoid contamination by particles adherent to intestinal mucosa the epithelium of intestinal tissue samples was removed before quantification. The number of fluorescent particles in tissues was determined by fluorescence microscopy of digests of selected samples. The uptake of particulate material across the intestinal wall was significantly (P < 0.05) increased in rats treated with dexamethasone but the number of particles transferred to systemic organs did not differ from values found for control animals. The results suggest that although dexamethasone increased intestinal permeability the apparatus or mechanisms involved in particle transport to distal sites were not affected during immune suppression.

Administration, Oral↗
PubMed1998

Transepithelial transport of large particles in rat: a new model for the quantitative study of particle uptake.

The transport of large particles across the intestinal mucosa and the mechanisms of transfer of the particles into the body are still little understood. Fluorescent polystyrene latex particles (2 microm diam.) were administered orally to young male Sprague-Dawley rats in doses of 2.33 x 10(3), 2.33 x 10(6) and 2.33 x 10(9) particles. After 60 min, Peyer's patches and Peyer's patch-free tissues were collected from the small intestine and colon. A novel technique was used to exclude non-translocated particles adherent to the mucosal surface; the intestinal epithelium was stripped from the intestine by immersion in Hanks' balanced salt solution containing 1.5 mM EDTA. Particles in solubilized samples of intact and epithelium-stripped Peyer's patches and Peyer's patch-free intestinal tissue and colon were quantified by fluorescence microscopy. The location of particles within the intact and epithelium-stripped gut samples was revealed by confocal microscopy. Particles were shown to have been taken up along the entire length of the small and large intestines via both Peyer's patches and the normal intestinal epithelium. The number of particles detected in the distal region was greater than in the proximal part of the small intestine, although the difference was not statistically significant. This study has revealed that large numbers of non-translocated particles adhered to the mucosal surface resulting in a high background count. The assay system was considerably improved by the epithelium-stripping technique. The process of transepithelial uptake is a potentially important route of uptake of toxic, immunologically active and radioactive substances. These particles are much larger than the conventionally accepted upper limit for absorbed materials.

Administration, Oral↗
PubMed1998

[Multiple osteonecrosis in a patient with chronic alcoholism].

The osteonecrosis is usually due to various precipitating circumstances or predisposing factors that quite often appear mixed, although it can also appear with no evident cause. In this report, we provide a case of multiple osteonecrosis caused by chronic alcoholism, we review the literature and go over the general characteristics of the aseptic necrosis.

Aged↗
PubMed1997

Preclinical studies for cell transplantation: isolation of primate fetal hepatocytes, their cryopreservation, and efficient retroviral transduction.

Fetal hepatocytes are an attractive target for in utero cellular transplantation. Their use could provide a very efficient way for implanting normal or transduced cells into the livers of affected fetuses. Marking cells with recombinant retroviruses is a powerful tool for evaluating the chimerism of grafted animals. The technique relies on the ex vivo transduction efficiency of the engrafted cells. We have isolated fetal primary hepatocytes from nonhuman primates. The cells were cultured and transduced with a retroviral vector carrying the Escherichia coli beta-galactosidase gene. Optimal gene transfer efficiency was obtained 48-60 hr after plating and was as high as 90%. Cryopreservation had little effect on cell viability and infectivity: The viability of thawed hepatocytes remained high (75-85%) and the infection efficiency was identical to that of freshly isolated cells. Efficient ex vivo retroviral gene transfer into fetal hepatocytes provides an appropriate system for testing allogenic grafting and for modifying immunogenicity of engrafted cells. These results open up new perspectives for cell transplantation through cell banking.

Animals↗
PubMed1997

Anatomical basis of a common embryological origin for epispadias and bladder or cloacal exstrophies.

Epispadias, bladder exstrophy and its variants are in the first place usually considered as urological anomalies. Embryological theses and therapeutic approaches are mainly based upon this aspect. We challenge this point of view, in order to bring out a new axis of research about this still misknown pathologic field. A review of 16 cases of bladder exstrophy, 6 epispadias cases, and one cloacal exstrophy case, which had never been described before, revealed that the almost constant bony defect of the pelvic ring was linked with the severity of the visceral features, and with the continence status in epispadias cases. The commonly admitted theories about exstrophy development are based on a primary defect of the cloacal membrane. We suggest that the first anomaly could lie in a lack of rotation in the pelvic ring primordia.

Bladder Exstrophy↗
PubMed1997

[Evaluation of hemostasis before obstetrical epidural anesthesia: a survey in 435 French obstetric departments].

OBJECTIVES: To specify by which means French anaesthesiologists evaluate the haemostasis profile of pregnant women before epidural analgesia. STUDY DESIGN: Nationwide retrospective survey. MATERIAL: Questionnaire sent of 847 French obstetrical units. METHODS: Comparison of categorical qualitative parameters using a chi 2 test. RESULTS: Answers from 435 centres, including 1,834 anaesthesiologists, performing 227 x 10(3) epidurals for 411 x 10(3) deliveries/year were obtained. A preanaesthetic clinical assessment was performed systematically in two out of three units, and blood samples for PT, aPTT and platelet count were taken in more than 90% of the centres. These laboratory examinations were often made during the 9th month of pregnancy (74%). For more than one-third of the anaesthesiologists, biological data are not essential before epidural puncture. In addition, the lower limits considered as being safe before epidural puncture were highly variable between the teams. CONCLUSIONS: Coagulation laboratory tests are almost always ordered before epidural obstetrical analgesia in France. The rationale to perform them is not always related to pregnancy induced haemostatic changes. Therefore, this problem should be clarified by a consensus conference for both practical and economical reasons.

Adult↗
PubMed1997

[Agranulocytosis after application of silver sulfadiazine in a 2-month old infant].

BACKGROUND: A granulocytosis associated with the use of silver sulfadiazine has been described in burn patients. This agranulocytosis may be due to either an allergic reaction or a bone marrow toxicity by silver sulfadiazine. CASE REPORT: A 1-month old baby was hospitalized in pediatric intensive care unit after a stage one repair of a tracheoesophegeal fistula. Gastroesophageal reflux and tracheomalacia appeared in the post operative period. When she was 2-months old, she developed a perineal erythema. A topical therapy was begun, with daily applications of silver sulfadiazine and ketoconazole. Five days later, agranulocytosis (granulocytes = 0.21 x 10(9).L-1) occurred. Silver sulfadiazine therapy was immediately stopped. Granulocyte count returned to normal over a few days. No other etiology than silver sulfadiazine could be found to explain agranulocytosis. The small surface of administration, the chronology of the events and the rapid correction of the disorders after silver sulfadiazine interruption argued for an immuno-allergic reaction to this drug. Medical problems were easily controlled and the patient recovered well. CONCLUSION: This event occurred when sulfadiazine was applied in a small cutaneous area in a young baby. This may be an argument for an allergic reaction; alternatively, it could be explained by an increased cutaneous absorption of a cytotoxic drug in younger people.

Agranulocytosis↗
PubMed1997

Effect of solid and liquid diet on uptake of large particulates across intestinal epithelium in rats.

The effect of diet composition on the uptake of particulates across the gastrointestinal epithelium has been examined in fasted male weanling Sprague-Dawley rats by estimating the systemic uptake of orally administered 2-microns latex polystyrene microspheres. Using a tissue solubilization assay, particle transfer in animals maintained on a fluid diet was determined. A larger number of particles was transferred from the gut lumen to the internal organs, including the mesenteric lymph node, spleen, bone marrow, liver, kidney, and heart of animals fed solid pelleted diet than those maintained on a fluid-diet 4 hr after oral administration of particles. The increase in particle number in rats fed the solid diet was only statistically significant (P < 0.05) for brain tissue in the analysis for trend. However, the number of particles retained in the proximal region of the gut at the end of this period was greater in animals fed the fluid diet. This work demonstrates that diet composition is important in gastrointestinal transepithelial translocation of microspheres.

Adolescent↗