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In light of evidence of linkage of obesity to chromosome 2q31-q37, we hypothesized that the calpain-10 gene 'high-risk' haplotype combination for non-insulin-dependent diabetes mellitus (NIDDM) is involved in early onset obesity. We screened the NIDDM 'high-risk'-haplotype combination formed by the alleles 112 and 121 of the polymorphisms UCSNP-43, -19, and -63 in 166 families consisting of an extremely obese child or adolescent (mean BMI percentile: 99.3+/-1.38), one or more obese sibs (mean BMI percentile: 97.42+/-2.88), and both of their parents. Genotyping for three calpain-10 gene polymorphisms was performed by polymerase chain reaction (PCR) with (a) length polymorphism detection (UCSNP-19) or (b) allele-specific PCR (UCSNP-43 and -63). To allow for correct haplotype assignment all individuals were additionally genotyped for two microsatellite markers (D2S125 and D2S2338). We followed a hierarchical test procedure. As the first step, model-free linkage analysis was performed using maximum likelihood binomial statistics. The second stage consisted of a one-sided asymptotic pedigree disequilibrium test for the UCSNP-43 and on an exploratory level for the other SNP-markers and all haplotypes formed by the three SNPs. The final stage investigated the reported haplotype combination. We failed to detect an initial linkage of obesity to this region (LOD score <0.4). All subsequent exploratory analyses were negative. Our analysis of the relationship between the NIDDM 'high-risk' haplotype combination and extreme early onset obesity revealed no evidence for linkage and association.  相似文献   
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The random amino acid copolymers FYAK and VWAK ameliorate EAE in a humanized mouse model expressing both a human transgenic myelin basic protein (MBP)85-99-specific T cell receptor and HLA-DR2. Here we show that microglia isolated from the central nervous system (CNS) of humanized mice with EAE induced by MBP85-99 and treated with these copolymers had reduced expression of HLA-DR, and thus reduced capacity to present MBP85-99 and activate transgenic T cells. In vitro microglia up-regulated empty HLA-DR2 upon activation with GM-CSF with or without LPS or IFN-gamma, but not with IL-4 or IL-10. Correspondingly, gene chip arrays showed that the CNS of untreated and YFAK-treated mice differentially expressed pro- and anti-inflammatory molecules during MBP85-99-induced EAE. Interestingly, microglia expressed the full-length gammabeta and alphabeta subunits of the tetrameric adaptor protein complexes AP-1 and AP-2 respectively, but after treatment with GM-CSF these complexes were cleaved, as had been found in immature dendritic cells derived from bone marrow. Strikingly, in vivo the perivascular lymphocyte infiltration seen in untreated mice immunized with MBP85-99 was composed of equal numbers of hVbeta2+ MPB85-99-specific transgenic and hVbeta2- endogenous T cells, while the much smaller infiltration seen after treatment with YFAK was composed predominantly of hVbeta2- endogenous T cells.  相似文献   
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During thymic development, immature thymocytes expressing major histocompatibility complex (MHC) class I-restricted T cell receptors (TcR) differentiate into CD8+ T cells with cytolytic functions. To evaluate the role of CD8 in positive and negative selection during thymic ontogeny, mice rendered CD8-null by gene targeting were bred with three lines of transgenic mice expressing unique MHC class I-restricted TcR. In all three instances CD8 was required for positive selection of MHC class I-restricted transgenic T cells. The efficiency of positive selection decreased in accordance with a reduced level of CD8 expression on thymocytes. Surprisingly, there was a differential requirement for CD8 expression in negative selection of MHC class I-restricted thymocytes, depending on the antigen specificity of TcR. These observations show that CD8 is essential for positive selection but is differentially required for negative selection of MHC class I-restricted T cells. Thus thymic selection, at least for negative selection, can occur in the absence of the CD8 accessory molecule.  相似文献   
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BACKGROUND: The aim of this study was to analyze changes of coping strategies in severely injured accident victims over time and to compare patients with high and low posttraumatic stress disorder (PTSD) symptom levels with regard to their coping patterns and accident-related cognitions. METHODS: 106 consecutive patients with severe accidental injuries admitted to a trauma surgery intensive care unit (ICU) were assessed within 1 month after the trauma and 6 and 12 months later. Assessments included a clinical interview, the Freiburg Questionnaire of Coping with Illness, the patients' accident-related cognitions, the Clinician-Administered PTSD Scale, the 90-item revised Symptom Checklist (SCL-90-R), and the Sense of Coherence Questionnaire (SOC). Patients who met the criteria for either full or subsyndromal PTSD at least once over the observation period (36 subjects; 34.0%) were assigned to a highly symptomatic group (HSG), the remainder (70 subjects; 66.0%) to a less symptomatic group. RESULTS: Overall, active problem-focused coping was predominant immediately after the accident and declined over time, with a stronger decrease in the HSG. Patients in the HSG scored higher on the SCL Global Severity Index and lower on the SOC. The patients' subjective appraisal of accident severity was higher in the HSG, whereas there was no group difference with regard to accident-related variables such as type of accident, injury severity and mild to moderate traumatic brain injury. CONCLUSIONS: Active problem-focused coping, although utilized most frequently and often regarded as protective, might be an inadequate strategy in face of acute stress following a severe accident. Clinicians should not expect their patients to cope very actively in the acute ICU phase. In the subsequent rehabilitation, active coping seems to be more adaptive.  相似文献   
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The T cell-mediated cytotoxic response against autologous cells modified with the sulfhydryl reagent I-AED (N-iodoacetyl-N'-(5-sulfonic-1-naphthyl) ethylene diamine) is hapten specific and H-2 restricted (Levy, R. B., Shearer, G. M., Richardson, J. C. and Henkart, P. A., J. Immunol. 1981. 127: 523). We have produced a monoclonal antibody (V-6-3, IgM) which binds to AED-modified cells and proteins. Competition experiments by free hapten indicated that the binding was AED specific. The effect of the mAb on AED-specific cytotoxic T cell recognition at the effector and induction stage has been examined. Anti-AED mAb inhibited the cell-mediated lysis of some but not all AED-specific, H-2b-restricted long-term cytotoxic T cell clones and of bulk-cultured C57BL/6 anti-AED-self effector cells. This blocking was not due to nonspecific agglutination of targets since lysis of AED-modified target cells by alloreactive effector cells was not affected by this mAb under comparable conditions. Furthermore anti-AED mAb specifically inhibited the antigen-induced proliferation of AED-specific long-term cytotoxic T cell clones and the generation of AED-specific cytotoxic effector cells in secondary cultures. This monoclonal anti-AED antibody bound to cells modified by the recently described aminoreactive reagent AED-NH2 (Takai, Y., Mizuochi, H., Fujiwava, H. and Hamaoka, T., J. Immunol. 1984. 132: 57); these same target cells were, however, not lysed by AED-SH-specific cytotoxic T cell clones.  相似文献   
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Zusammenfassung Nach multiplem Trauma sinken intracelluläre Aktivität und Konzentration der Elastase in polymorphkernigen Leukocyten (PMNL), die aus Blut ( = 67 U und 6154 g/109 PMNL) und bronchoalveolärer Lavage (BAL)-Flüssigkeit ( = 44 U und 5957 g/109 PMNL) isoliert wurden im Vergleich zu PMNL Gesunder ( = 106 U und 9962 g/109 PMNL). Gleichzeitig wurde ein Anstieg der extracellulären Elastase-Konzentration in Plasma von = 84 g/1 auf = 399 g/1 und in BAL Flüssigkeit von = 8 g/1 auf = 561 g/1 beobachtet. Die durch Stimulation freigesetzte Elastase wird teilweise von einem spezifischen Receptor auf PMNL erneut gebunden. Die Ergebnisse unterstützen die PMNL-vermittelte ARDS-Pathogenese.  相似文献   
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OBJECTIVE: To acquire data on pediatric nosocomial infections (NIs), which are associated with substantial morbidity and mortality and for which data are scarce. DESIGN: Prevalence survey and evaluation of a new comorbidity index. SETTING: Seven Swiss pediatric hospitals. PATIENTS: Those hospitalized for at least 24 hours in a medical, surgical, intensive care, or intermediate care ward. RESULTS: Thirty-five NIs were observed among 520 patients (6.7%; range per hospital, 1.4% to 11.8%). Bacteremia was most frequent (2.5 per 100 patients), followed by urinary tract infection (1.3 per 100 patients) and surgical-site infection (1.1 per 100 patients; 3.2 per 100 patients undergoing surgery). The median duration until the onset of infection was 19 days. Independent risk factors for NI were age between 1 and 12 months, a comorbidity score of 2 or greater, and a urinary catheter. Among surgical patients, an American Society of Anesthesiologists (ASA) score of 2 or greater was associated with any type of NI (P = .03). Enterobacteriaceae were the most frequent cause of NI, followed by coagulase-negative staphylococci; viruses were rarely the cause. CONCLUSIONS: This national prevalence survey yielded valuable information about the rate and risk factors of pediatric NI. A new comorbidity score showed promising performance. ASA score may be a predictor of NI. The season in which a prevalence survey is conducted must be considered, as this determines whether seasonal viral infections are observed. Periodic prevalence surveys are a simple and cost-effective method for assessing NI and comparing rates among pediatric hospitals.  相似文献   
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Male strain A/J mice were exposed for six hours a day, five days a week for six months to either full tobacco smoke or to tobacco smoke drawn through a HEPA filter that removed more than 99% of particulate matter. After another four months in air, the animals were sacrificed and lung tumors were counted for calculation of multiplicities and incidences. Analysis of the chamber atmospheres showed that in the filtered smoke the concentrations of polycyclic aromatic hydrocarbons and tobacco smoke specific nitrosamines were reduced to from below 18% to even nondetectable levels of the original values measured in the unfiltered smoke. Aldehydes and other volatile organic compounds such as 1,3-butadiene, benzene, or acrolein were reduced to about 50 to 90% of the concentrations found in unfiltered smoke. Some potentially carcinogenic metals reached levels in filtered smoke ranging from 77% to less than 1% found in full smoke. The mice exposed to the filtered smoke atmosphere had practically identical lung tumor multiplicities and incidence as had the animals exposed to full smoke, significantly higher than in air exposed controls. Diets containing 0.5% beta-carotene or 0.4% N-acetylcysteine afforded some chemoprevention. It was tentatively concluded that 1,3-butadiene might be an important contributor to lung tumorigenesis in this mouse model of tobacco smoke carcinogenesis.  相似文献   
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