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51.
Deletions of 22qll cause DiGeorge sequence (DGS), velo-cardio-facial syndrome (VCFS), conotruncal anomaly face syndrome, and some isolated conotruncal heart anomalies. Demonstration of a 22qll deletion in a patient with manifestations of DGS and Noonan syndrome (NS) has raised the question of whether NS is another of the chromosome 22 microdeletion syndromes. This prompted us to evaluate a cohort of patients with NS for evidence of 22qll deletions. Five of 6 NS propositi studied in our laboratory with marker N25 (D22S75) did not have a 22qll deletion. A 2-month-old infant with several findings suggestive of NS did have a 22qll deletion, suggesting that a small number of 22qll deletion propositi may present with a NS-like picture. However, most cases of NS must have another cause. © 1995 Wiley-Liss, Inc.  相似文献   
52.
Human keratinocytes (HK) generate nitric oxide (NO) and proinflammatory mediators following activation with either IgE/anti-IgE immune complexes or a combination of lipopolysaccharide (LPS) and interferon-γ (IFN-γ). Recently, interleukin-10 (IL-10) has been shown to down-regulate various inflammatory responses and to be secreted by lymphocytes and dendritic cells during skin inflammatory reactions. We show here that IL-10 down-regulates the production of tumor necrosis factor (TNF)-α and IL-6 by activated HK. Also, induction of inducible nitric oxide synthase (iNOS) expression in HK by IgE/anti-IgE or LPS/IFN-γ is significantly reduced by the addition of IL-10. This effect is dose dependent and correlates with reduction of iNOS mRNA production and enzyme level. Therefore, IL-10 down-regulates NO-mediated HK inflammatory responses and may thus participate in the regulation of the skin immune network.  相似文献   
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Cytogenetic studies in peripheral blood and bone marrow cells from a female patient (aged 31 years) with inherited aplastic anemia and without other congenital anomalies are reported. Endoreduplication was increased in stimulated peripheral lymphocytes in several investigations. Chromosome breaks were shown to be near the control frequency, although chromatid exchange figures and dicentrics were present. Cytogenetic analysis was extended to the three children of our patient. Abnormal clones were detected in bone marrow preparations of our patient in all cytogenetic investigations. At the first examination, two of these clones were prevalent, with their karyotypes being 48,XX,+9,+16 and 46,XX,dup(1)(q24→q32),t(17;?)(p12–13;?). The prevailing karyotype after 2 years was 46,XX,t(17;?)(p12–13;?). Involvement of chromosomes #1 and #17 is discussed, taking into account data from the literature concerning several human neoplasias.  相似文献   
55.
Several multiple, large-scale, genetic studies on autoimmune-disease-associated SNPs have been reported recently: peptidylarginine deiminase type 4 (PADI4) in rheumatoid arthritis (RA); solute carrier family 22 members 4 and 5 (SLC22A4 and 5) in RA and Crohns disease (CD); programmed cell death 1 (PDCD1) in systemic lupus erythematosus (SLE), type 1 diabetes mellitus (T1D), and RA; and protein tyrosine phosphatase nonreceptor type 22 (PTPN22) in T1D, RA, and SLE. Because these reports on association were not always evaluated in multiple ethnic groups and because ethnic difference in allele frequency of the variants has been also reported, we investigated allele frequencies of nine SNPs in four autoimmune-disease-associated loci in Caucasian, African-descent, and Japanese populations. Although SNPs in PADI4 had similar allele frequency among three groups [maximal difference 11%; (P >0.05)], the other three loci revealed statistically significant allele frequency differences (maximal difference 39% (P <0.00001), 13% (P <0.00001), and 8% (P <0.00001) in SLC22A4, PDCD1, and PTPN22, respectively). Of note, three SNPs in the three loci that had allele frequency more than 8% in the Caucasian population were either not polymorphic at all or extremely rare in the Japanese population. Our data suggest that ethnic variations of polymorphisms should be evaluated in detail, and differences should be incorporated into investigations of susceptibility variants for common diseases.  相似文献   
56.
Malignant rhabdoid tumor (MRT) is a highly malignant pediatric cancer, which arises in various sites such as the kidney, brain, and soft tissues. Cytogenetic studies have revealed alterations of 22q11 in MRT. Recently, deletions and mutations of the SNF5/INI1 locus in 22q11.2 have been reported in MRT, suggesting that SNF5/INI1 is a tumor suppressor gene for MRT. Here we report our molecular cytogenetic study for a newly established cell line from extrarenal MRT with t(1;22)(p36;q11.2). Consequently, the reciprocal translocation was associated with the interstitial deletion of a small segment including SNF5/INI1, and another, chromosome 22, showed terminal deletion, the breakpoint of which was located 70–80 kb centromeric to SNF5/INI1, resulting in homozygous deletion of SNF5/INI1 in this cell line.  相似文献   
57.
IL-13对大鼠急性肾缺血再灌注时IL-1β表达的影响   总被引:2,自引:0,他引:2  
目的:观察IL-13对急性肾缺血再灌注时IL-1β表达的影响。方法:Wistar雄性大鼠57只,随机分为8组:正常组(normal);假手术组(sham);缺血组:(I)缺血再灌注组(I/R);治疗对照组-1(C-1);治疗对照组-2(C-2);治疗组-1(T-1)和治疗组-2(T-2)。阻断大鼠双侧肾脏血流45min再灌注24h建立急性肾缺血再灌注模型;治疗组分别于阻断血流前、后分别从双侧肾动脉开口注射入1.5μg/50gbw鼠重组白细胞介素13(rmIL-13);检测各组大鼠IL-1β血清水平和肾脏表达,以及肾功能和肾脏病理。结果:(1)治疗组肾脏IL-1β基因(TtoC:P<0.01)和蛋白表达(T-1toC-1:P<0.01;T-2toC-2:P<0.05)明显减少,血清IL-1β水平明显下降;(2)肾功能障碍和肾组织病理变化明显减轻,肾小管损害评分减少(C-1toT-1:45.20±8.64to21.05±8.82,P<0.01;C-2toT-2:42.25±11.15to23.25±7.31,P<0.01);(3)血清IL-1β水平与BUN、Cr成正相关(r=0.708,P<0.01;r=0.770,P<0.01)。结论:IL-13能有效地抑制大鼠急性肾缺血再灌注损伤IL-1β的表达。  相似文献   
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59.
Extracts of Tripterygium wilfordii Hook F.(TWHF ) are effective in traditional Chinesemedicine for treatment of autoimmune diseasessuch as rheumatoid arthritis, systemic lupus ery thematosus, nephritis and asthma [1, 2]. Trip tolide, a diterpenoid triepoxide, is derived fromTWHF and is responsible for most of the immuno suppressive and anti inflammatory effects ofTWHF. Triptolide has been shown to be effectivein the treatment of autoimmune diseases, …  相似文献   
60.
目的:通过研究细胞因子对FN表达的调节,探讨FN在围着床期子宫内膜表达的调节机理。方法:给孕早期小鼠注射不同的细胞因子,收集子宫内膜。分别用Immuno-blot法及RT-PCR法测定子宫内膜FN蛋白和nRNA的水平。结果:LIF低、高剂量组的FNmRNA和蛋白水平都比对照组高,统计分析差异有显著性(P<0.05,P<0.01),IL-1和IL-1ra各组FN水平与对照组比无显著差异。结论:LIF在转录和转录后水平上调早期子宫内膜FN的表达,LIF参与着床与调节粘附分子的表达有关。IL-1系统则不影响子宫内膜FN的合成。  相似文献   
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