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31.
Human chromosome 6 encodes both the interferon gamma receptor as well as the class I major histocompatability complex antigens, HLA-A, -B, and -C. However, the presence of chromosome 6 in somatic cell hybrids is insufficient to confer sensitivity to human interferon gamma (Hu-IFN-) as assayed by class I HLA induction; it is necessary for both human chromosomes 6 and 21 to reside in the hybrid to generate a response to Hu-IFN-. Treatment of such a hamster-human hybrid, Q72-18, with Hu-IFN- induces the class I HLA antigens. Q72-18 cells selected by fluorescence-activated cell sorting for the loss of class I HLA induction also lost human chromosome 21. Fusions of such cells to a hybrid that contains only human chromosome 21 reconstitutes HLA antigen induction by Hu-IFN-. Furthermore, fusions of hybrids containing a translocated human chromosome 6q and the HLA-B7 gene to a line containing only human chromosome 21 or a translocated 21q also reconstitutes HLA-B7 mRNA and antigen induction by Hu-IFN-. Thus the segregation of cells on the basis of a biological effect by fluorescence-activated cell sorting and reconstitution by hybrid fusion provides a strategy by which some biological pathways can be mapped at a chromosomal level.  相似文献   
32.
Acute rejection is a major determinant of chronic allograft dysfunction and graft survival. This study evaluated the effect of basiliximab (Simulect®), a 156-kDa chimeric monoclonal antibody (human and murine) directed against the alpha chain of the interleukin (IL)-2 receptor of human lymphocytes, on acute rejection in pediatric renal transplantation. Data were collected from two pediatric renal transplantation centers. Forty transplantations (22 males and 18 females; mean age 14.8±3.6 years) were performed between 1996 and 2001. Twelve of the grafts came from cadaveric donors and 28 from living-related donors. Twenty-four of the patients were on hemodialysis, 15 were on peritoneal dialysis, and one case was a pre-emptive transplantation. All patients were placed on triple-drug immunosuppression [prednisolone + (azathioprine or mycophenolate mofetil) +(cyclosporine or tacrolimus)]. Basiliximab was also administered in 17 cases. The respective rates of biopsy-proven acute rejection in the basiliximab group and the standard-regimen group were 0% vs. 17.4% ( P >0.05) at 1 month post-transplantation; 0% vs. 26.1% ( P <0.05) at 3 months; and 0% vs. 26.1% ( P <0.05) at 6 months. Thirty and 16 patients had completed 1- and 3-year follow ups, respectively, at the time of writing; the 1- and 3-year graft survival rates were 96% (29/30) and 81% (13/16), respectively.
Basiliximab significantly reduced the rates of acute rejection at 3- and 6 months post-pediatric renal transplantation. It was well tolerated by all patients, and caused no significant adverse effects. The effect of basiliximab on long-term graft survival and chronic allograft dysfunction deserves further investigation.  相似文献   
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Machado-Joseph disease (MJD) is an autosomal dominant neurodegenerative disorder caused by unstable expansion of a CAG repeat in the MJD1 gene at 14q32.1. To identify elements affecting the intergenerational instability of the CAG repeat, we investigated whether the CGG/GGG polymorphism at the 3' end of the CAG repeat affects intergenerational instability of the CAG repeat. The [expanded (CAG)n-CGG]/[normal (CAG)n- GGG] haplotypes were found to result in significantly greater instability of the CAG repeat compared to the [expanded (CAG)n- CGG]/[normal (CAG)n-CGG] or [expanded (CAG)nGGG]/[normal (CAG)n-GGG] haplotypes. Multiple stepwise logistic regression analysis revealed that the relative risk for a large intergenerational change in the number of CAG repeat units (< -2 or > 2) is 7.7-fold (95% CI: 2.5-23.9) higher in the case of paternal transmission than in that of maternal transmission and 7.4-fold (95% CI: 2.4-23.3) higher in the case of transmission from a parent with the [expanded (CAG)n-CGG]/[normal (CAG)n-GGG] haplotypes than in that of transmission from a parent with the [expanded (CAG)n-CGG]/[normal (CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal (CAG)n-GGG] haplotypes. The combination of paternal transmission and the [expanded (CAG)n-CGG]/[normal (CAG)n-GGG] haplotypes resulted in a 75.2-fold (95% CI: 9.0-625.0) increase in the relative risk compared with that of maternal transmission and the [expanded (CAG)n-CGG]/[normal (CAG)n-CGG] or [expanded (CAG)n- GGG]/[normal (CAG)n-GGG] haplotypes. The results suggest that an inter- allelic interaction is involved in the intergenerational instability of the expanded CAG repeat.   相似文献   
35.
The problem of morphine tolerance and dependence is a universal phenomenon threatening social health everywhere the world. The major objective of this paper was to investigate the effects of fruit essential oil (FEO) of Cuminum cyminum on acquisition and expression of morphine tolerance and dependence in mice. Animals were rendered dependent on morphine using the well-established method in which was morphine (50, 50, 75 mg/kg; s.c.) injected three times daily for 3 days. In experimental groups, administration of FEO (0.001, 0.01, 0.1, 0.5, 1 and 2%; 5 ml/kg; i.p.) or Tween-80 (5 ml/kg; i.p.) was performed 60 min prior to each morphine injection (for acquisition) or the last injection of morphine on test day (for expression). Morphine tolerance was measured by tail-flick before and after administration of a single dose of morphine (50 mg/kg; s.c.) in test day (4th day). Morphine dependence was also evaluated by counting the number of jumps after injection of naloxone (5 mg/kg; i.p.) on the test day. The results showed that Cumin FEO, only at the dose of 2%, significantly attenuated the development of morphine tolerance (P < 0.01) and dependence (P < 0.05) while it could be significantly effective on expression of morphine tolerance (1 and 2%) and dependence (0.5, 1 and 2%) in a dose-dependent manner. Solely Cumin FEO injection (0.001–2%) did not show any analgesic effect. In conclusion, the essential oil of Cuminum cyminum seems to ameliorate the morphine tolerance and dependence in mice.  相似文献   
36.
Varicella-zoster virus (VZV) DNA was detectable by in-situ hybridization in blood mononuclear cells (MNCs) of patients with varicella or zoster for 2–56 days after the onset of a rash. VZV DNA was present in many MNCs from one acute varicella patient 2 days after the onset of the rash and was rarely found in MNCs during acute zoster, convalescent zoster, and convalescent varicella. The morphology of MNCs containing VZV was heterogenous, although most viral-DNA-containing MNCs were large monocytoid cells. Serial examination of blood MNCs from one adult with varicella revealed VZV DNA up until 8 weeks, but not 16 weeks, after the appearance of the rash; parallel studies in four zoster patients showed VZV DNA up until 3 weeks, but not later than 7 weeks after the appearance of the rash. These results indicate that MNCs become infected with VZV during the primary encounter with VZV (varicella) and during reactivation (zoster) and that infection continues for weeks after the onset of the skin rash. Furthermore, the detection of VZV DNA in blood MNCs of uncomplicated zoster patients coincides with the period during which these patients experience pain.  相似文献   
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38.
Immunologic enhancement of renal allografts from (Lewis times Brown Norway) F1 to Lewis rats was achieved by administering a single dose of antidonor serum at the time of transplantation. A series of grafts functioning for 1 to 4 months after transplantation were examined by light and immunofluorescence microscopy to evaluate the long-term protective effects of the enhancing serum and to determine if previously unobserved lesions appeared in long survivors. Despite the absence of detectable circulating cytotoxic alloantibody, long-term allografts showed necrotizing glomerular and arterial lesions which resembled those seen in acutely rejecting grafts and were compatible with humoral rejection. Thus, in this model, there is a late decline in the ability of passive enhancement to inhibit humoral rejection. Long-term grafts also developed tubular lesions with deposition of immunoglobulin and complement on the tubular basement membranes (TBM). Anti-TBM antibodies were demonstrated in recipients' sera and found to be organ specific but not major histocompatibility antigen or species specific. This tubular lesion is therefore a unique form of allograft injury in which the immune response is directed against tissue antigen(s) which are distinct from the major histocompatibility antigens that induce rejection.  相似文献   
39.
A Pakistani kindred comprising 5 generations contained 9 males and 4 females with alopecia universalis as a single abnormality without any associated defects. The skin biopsy from the scalp showed hair follicles without hair. Analysis of the pedigree is strongly suggestive of autosomal recessive inheritance, and consanguineous loops could account for all affected persons being homozygous for the abnormal allele. © 1993 Wiley-Liss, Inc.  相似文献   
40.
Stability of Th1 and Th2 populations   总被引:19,自引:0,他引:19  
Using an in vitro model for the development of IFN-y-producIng(Th1) and IL-4-produclng (Th1) cells from CD4 T lymphocytesexpressing a transgenlc TCR, we show that IL-12 and IL-4 arethe most potent stimuli for the differentiation of naive T cellsto effector populations. When combinations of cytokines arepresent during T cell priming, the effect of IL-4 Is dominant.Furthermore, differentiated Th1 cells can be converted intoIL-4 producers by exposure to IL-4, but the Th2 phenotype Isnot reversible. The stability of Th2 populations may limit theability to regulate Th2-domlnant responses In pathologic situations.  相似文献   
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