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31.
Cells from three patients with early gonadal failure and a balanced reciprocal translocation involving the long arm of the X chromosome and an autosome were studied. Fibroblasts from a patient with a similar balanced reciprocal translocation but normal reproductive capabilities were also studied. Two of the four patients were found to have serologically detectable H-Y antigen on their cells. Since H-Y antigen has been found on the cells of other patients with X chromosome abnormalities but without a Y chromosome, it is thought that the X chromosome plays a role in the regulation of H-Y antigen expression. This study suggests that the long arm of the X chromosome may be involved but the location of a regulatory gene cannot be identified in these studies. These cases do not permit us to implicate H-Y antigen as a cause of gonadal dysgenesis and early gonadal failure in females who have structurally abnormal X chromosomes.  相似文献   
32.
Differential effects of interleukin-4 in peptide induced autoimmunity   总被引:1,自引:0,他引:1  
BALB/c mice immunized with multimeric DWEYSVWLSN develop IgG1 anti-DNA antibodies and glomerular immunoglobulin deposits, leading us to investigate the role of IL-4 in this model of antigen induced lupus. Splenocytes from DWEYSVWLSN immunized mice secreted IL-4 but not gamma-interferon. Following peptide immunization, IgG1 anti-peptide and anti-DNA antibodies were significantly higher in IL-4 wild type mice, while IgM and IgG3 anti-DNA levels were significantly higher in IL-4 knockout mice. Titers of IgG anti-laminin and anti-histone, but not anti-Sm/RNP and anti-cardiolipin antibodies, were significantly higher in the IL-4 wild type group. Glomerular immunoglobulin deposition was substantially decreased in IL-4 knockout mice. We conclude that while IL-4 does not materially affect the generation of some autoantibody responses associated with peptide induced autoimmunity, IL-4 deficiency inhibits kidney immunoglobulin deposition. The effect of IL-4 on humoral autoimmunity in lupus is complex, and is dependent on genetic background, the antigenic trigger and stage of disease.  相似文献   
33.
It is increasingly recognized that the identification of t(11;22)(q24;q12) is a useful aid in the accurate diagnosis of Ewing's sarcoma and related tumours. However, cytogenetic studies have a low success rate and adequate tumour is not always available. This study describes the use of fluorescence in situ hybridization (FISH) to detect translocations at 22q12, the site of the EWS gene involved in t(11;22)(q24;q12), on tumour touch imprints made from true cut core-needle biopsy and frozen tumour. Of the seven tumours analysed, five diagnosed as Ewing's sarcoma or primitive neuroectodermal tumour demonstrated chromosome translocation at 22q12. This is a rapid and reliable method to detect a diagnostically relevant chromosome translocation using minimal amounts of fresh or frozen tumour.  相似文献   
34.
In order to evaluate the relationship between serum concentrations of interleukin-10 (IL-10), IL-6, and acute phase proteins in rheumatoid arthritis (RA) patients treated with methotrexate (MTX) or intramuscular gold (IMG) we determined IL-10, IL-6, C-reactive protein (CRP), alpha-1-acid glycoprotein (AGP) and alpha-1-antichymotrypsin (ACT) in the sera of 35 RA patients. IL-10 and IL-6 levels were evaluated using an enzyme-linked immunoassay (ELISA). AGP and ACT level were measured using rocket immunoelectrophoresis. IL-10 serum level was not increased in RA patients as compared to controls (58.7 ± 18.1 pg/ml vs. 57.2 ± 11.9 pg/ml). IL-6 level was significantly elevated (91.6 ± 46.9 pg/ml vs. 45 ± 19 pg/ml, p < 0.05). CRP was significantly increased as compared to healthy controls (35 ± 19 mg/l vs. 3 ± 2 mg/l, p < 0.05). Patients treated with MTX or IMG presented an increased level of IL-10 and decreased amounts of IL-6, as compared to those treated with NSAID only. However, only changes between patients treated with IMG and NSAID were found to be statistically significant. A good negative correlation between IL-10 and IL-6 serum level was found (r = –0.75, p < 0.05). A positive significant correlation between IL-6 serum level and CRP (r = 0.62, p < 0.05), AGP (r = 0.78, p < 0.05) and ACT (r = 0.45, p < 0.05) was established. On the other hand, a negative correlation between IL-10 and serum level of CRP (r = –0.76, p < 0.05), AGP (r = –0.64, p < 0.05) and ACT (r = –0.38, p < 0.05) was also observed. Moreover, these relationships were maintained when patients treated with MTX, IMG, or NSAID were analyzed independently. According to the data thus far obtained, it seems that IL-10 decreases IL-6 production, and thereby indirectly affects the acute phase response, decreasing CRP, AGP, and ACT concentration in RA patients.Abbreviations ACT -1-antichymotrypsin - AGP 1-acid glycoprotein - APP acute phase protein - CRP C-reactive protein - CSF colony stimulating factor - IFN interferon - IL interleukin - IMG intramuscular gold - MTX methotrexate - NSAID non-steroidal anti-inflammatory drug - RA rheumatoid arthritis  相似文献   
35.
The focus of our research is to understand the immune response to foreign tissue. We believe that adichotomy exists within the immune response to an allograft such that part of the response is dedicated to the protection of the graft. Nevertheless, in a dominantly graft-aggressive environment, rejection typically ensues. In this article, we describe models that have been set up to test directly the ability of potentially protective aspects of the immune response to prevent allograft rejection. We discussour data in the context of a growing body of exciting and often controversial literature.  相似文献   
36.
We found a HhaI/BstUI polymorphism in the 3′ untranslated region of a novel gene which was localized to 11p15.5. This region is one of prominent imprinting domains and contains multiple imprinted genes, such as H19, IGF2 , KVLQT1, and p57 KIP2 , which suggests that regional factors might contribute to the imprinting. This polymorphism will be useful in the allelic analysis of expression and methylation of the novel gene. Received: July 24, 1998 / Accepted: July 29, 1998  相似文献   
37.
Experiments on cats showed that injury to the medial forebrain bundle (MFB) and also partly to the preoptic region on the side of application of penicillin to the cerebral cortex (middle suprasylvian gyrus) causes depression of paroxysmal activity (spike potentials) in the penicillin focus, and also in a secondary mirror focus arising in the symmetrical zone of the opposite cortex. Injury to MFB on the side of the mirror focus causes depression of paroxysmal spike potentials only in that focus and does not affect activity in the primary epileptiform focus. The effects described are examined from the standpoint of views regarding the role of the determinant dispatch station (DDS) in the activity of the CNS: A primary epileptiform focus is a hyperactive DDS which induces the appearance of secondary foci, supports them, and determines the character of their activity. The results of the investigation suggests a role for MFB in the modulation of cortical epileptiform activity.Laboratory of General Pathology of the Nervous System, Institute of General Pathology and Pathophysiology, Academy of Medical Sciences of the USSR, Moscow. Laboratory of Electrophysiology, V. F. Filatov Odessa Research Institute for Eye Diseases and Tissue Therapy, Ministry of Health of the Ukrainian SSR. Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 82, No. 12, pp. 1413–1416, December, 1976.  相似文献   
38.
We report the unusual occurrence of Kaposi’s sarcoma following asbestos-related malignant mesothelioma, in a human deficiency virus (HIV)-negative Italian man. Seropositivity to human herpes virus 8 (HHV8) was documented at the time of mesothelioma diagnosis and preceded the onset of Kaposi’ sarcoma with a time lapse of 13 months. HHV8 DNA was detected by polymerase chain reaction in lesional Kaposi’s sarcoma but not within mesothelioma. By immunostaining, mesothelioma cells expressed interleukin-6 and platelet-derived growth factor, which are important for survival of Kaposi’s sarcoma cells. Besides the possibility of a casual association, we hypothesize that mesothelioma-linked factors may have contributed to the development of Kaposi’sarcoma in the presence of HHV8 infection. Received: 12 April 1999 / Accepted: 24 June 1999  相似文献   
39.
The effects of gangliosides on human plasma cell responses were studied. Among the various gangliosides tested, only GM1 enhanced immunoglobulin (Ig) production and proliferation in the human plasma cell lines, IM-9 and AF-10, while other gangliosides (GM2, GM3, GD1a, GD1b, GD3, GT1b, and GQ1b) had no effect. Among the various cytokines tested, including interleukin (IL)-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-10, IL-12, IL-13, interferon (IFN)-α and IFN-γ, only IL-6 enhanced Ig production and proliferation in IM-9 and AF-10 cells. However, the enhancement of plasma cell responses by GM1 was specific and was not mediated by IL-6, since GM1 activity was blocked by anti-GM1 monoclonal antibody (mAb), but not by control IgM, anti-IL-6 Ab or the anti-IL-6 receptor mAb, PM1. Conversely, the enhancement by IL-6 was blocked by anti-IL-6 Ab and PM1, but not by anti-GM1 mAb. GM1, but not other gangliosides, also enhanced Ig production and proliferation in freshly separated plasma cells from patients with plasma cell leukemia and in plasma cells generated in vitro. These actions of GM1 were specifically blocked by anti-GM1 mAb, but not by anti-IL-6 Ab or PM1. These results indicate that GM1 may be an important regulator of plasma cell responses.  相似文献   
40.
P15E is a specific sequence among the envelope gene (env)-encoded transmembrane proteins of exogenous and endogenous retroviruses. A synthetic peptide (CKS-17) that shows homology to this p15E region in several species of retrovirus is known to induce immune abnormalities. In this study, we examined the effect of a synthetic peptide derived from a region of human endogenous retrovirus (HERV) clone 4-1 ( 4-1) similar to sequences of CKS-17 on the induction of systemic lupus erythematosus (SLE)-related immune abnormalities. Our results indicated that this peptide could induce T-cell activation and anergy in normal peripheral blood mononuclear cells, and the peptide could also promote the production of interleukins IL-6 and IL-16. These phenomena are representative immune abnormalities observed in SLE patients. Thus, our findings support the possibility that HERV acts as a pathogen in human SLE.  相似文献   
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