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Hyperekplexia is a rare, autosomal dominant neurological disorder characterized by hypertonia, especially in infancy, and by an exaggerated startle response. This disorder is caused by mutations in the ?1 subunit of the inhibitory glycine receptor (GLRA1). We previously reported two GLRA1 point mutations detected in 4 unrelated hyperekplexia families; both mutations were at nucleotide 1192 and resulted in the replacement of Arg271 by a glutamine (R271Q) in one case and a leucine (R271L) in the other. Here, 5 additional hyperekplexia families are shown to have the most common G-to-A transition mutation at nucleotide 1192. Haplotype analysis using polymorphisms within and close to the GLRA1 locus suggests that this mutation has arisen at least twice (and possibly four times). In 2 additional families, a third mutation is also presented that changes a tyrosine at amino acid 279 to a cysteine (Y279C). Five patients with atypical clinical features and equivocal or absent family history of hyperekplexia and 1 patient with a classical presentation but no family history are presented in whom a mutation in the GLRA1 gene was not detected. Thus, only clinically typical hyperekplexia appears to be consistently associated with GLRA1 mutations, and these affect a specific extracellular domain of the protein.  相似文献   
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The proportion and changes of CD4 CD25high regulatory T cells (Trs) in peripheral blood of non-small cell lung cancer (NSCLC) patients were analyzed and their clinical significance explored. The peripheral blood was collected from 61 patients with NSCLC and 15 healthy controls. By using monoclonal antibodies, the blood samples were evaluated with the flow cytometry for lymphocyte subsets (CD3 , CD4 and CD8 ) and CD4 CD25high Tr cells. The results showed that the proportion of CD4 CD25high Tr cells in NSCLC group was significantly higher than in control group [(4.36±2.07) % vs (2.04±1.03) %, P<0.01]. The proportion of CD4 CD25 high Tr cells in late stage was higher than that in early stage [stages I II (2.26 0.6) %; stage III (3.28 1.38) %; stage IV (6.06±4.08) %] (P<0.05). Kaplan-Meier survival analysis revealed that the prognosis of the patients who had higher proportion of CD4 CD25high Tr cells in peripheral blood was worse (P=0.0026). In conclusion, the relative increase in CD4 CD25high Tr cells in peripheral blood may be related to im-munosuppression and tumor progression in patients with NSCLC. This finding suggests that CD4 CD25 high Tr cells in peripheral blood of NSCLC may be positive for prognosis analysis. The use of depletion of the CD4 CD25high Tr cell therapy to treat NSCLC patients may be an effective strategy.  相似文献   
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本文应用先进的极限稀释微孔培养技术,成功地培养出人骨髓粒-单祖细胞(CFU-GM),并在方法学上作了改进,能够获得完整清晰的集落形态。采用线性回归分析、标记性染色体、3_H-TdR参入、扫描电镜等多种手段证实了CFU-GM的克隆性生长和极限稀释微孔培养CFU-GM的优点。  相似文献   
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BACKGROUND/AIMS: Central vein catheters for patients receiving total parenteral nutrition have a high incidence of colonized catheters and catheter-related bloodstream infections. However, the actual incidence and bacterial pattern have not been well studied. This study was undertaken to investigate the difference in bacteriology between colonized catheters and catheter-related bloodstream infections. METHODOLOGY: From January 1997 to March 1998, 354 patients receiving total parenteral nutrition were included in this study. The patients ranged in age from 49 to 80 years, 151 women and 203 men. Colonized catheters and catheter-related bloodstream infections were defined. RESULTS: The culture was performed in 249 catheter tips (249 of 614, 40.6%). Sixty tips were found to have organisms. The organisms cultured from colonized catheters were Gram(+) aerobic bacteria (34, 56.7%), fungi (14, 23.3%), and Gram(-) aerobic bacteria (12, 20%). The organisms cultured from catheter-related bloodstream infections were fungi (16, 64%), Gram(-) aerobic bacteria (5, 20%), and Gram(+) aerobic bacteria (4, 16%). Dermatogenic infection in colonized catheters should be stressed, but systemic fungal infection in catheter-related bloodstream infections should be emphasized. CONCLUSIONS: A striking difference exists in bacterial species between colonized catheters and catheter-related bloodstream infections. Further studies on different treatment strategy for colonized catheters and catheter-related bloodstream infections should be undertaken. The combined approach of a total parenteral nutrition team, sterile protocols, and early diagnosis of fungemia should be advocated for the total parenteral nutrition patients.  相似文献   
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Journal of Autism and Developmental Disorders - Atypical eating behaviors displayed by children with autism spectrum disorder (ASD) predispose them to unhealthy weight gain. We determined the...  相似文献   
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PURPOSE: Regulatory T cells (T-reg) that control harmful autoimmune T cells in the periphery may also suppress the immune response against cancer. In this study we investigated the possible involvement of CD4(+)CD25(high) T-reg in the immune impairment of patients with acute myeloid leukemia (AML). EXPERIMENTAL DESIGN: The frequencies and phenotypes of CD4(+)CD25(high) T cells in the peripheral blood of AML patients were determined by flow cytometry. To assess the functional activity of CD4(+)CD25(high) T cells, CD4(+)CD25(high), and CD4(+)CD25(-) T cells were sorted from peripheral blood mononuclear cells with FACS Vantage. The immunoregulatory properties of CD4(+)CD25(high) and CD4(+)CD25(-) T cells were characterized by proliferation assays and cytokine production assays. In addition, the frequency of apoptotic and proliferating cells in CD4(+)CD25(high) T cells were respectively evaluated by 7AAD and ki67 binding cells using flow cytometry. RESULTS: Compared with healthy controls, AML patients had a higher proportion of CD4(+)CD25(high) T cells in peripheral blood. These cells were CD45-RA(-), CD69(-), CD45-RO(+), CD95(+), and intercellular CTLA-4(+), and secreted low levels of TNF-alpha and IL-10, but no IL-2, IL-4, IL-5, and IFN-gamma. They inhibited the proliferation and cytokine production (IL-2, IFN-gamma) of CD4(+)CD25(-) T cells, but improved IL-10 production under the co-culture of both subsets with stimulation, thus behaving as T-reg. Notably, CD4(+)CD25(high) T cells in AML patients presented significantly higher apoptosis and proliferation than that of healthy individuals. CONCLUSIONS: The frequency of CD4(+)CD25(high) T-reg in peripheral blood in AML patients is significantly higher when compared with healthy individuals, likely due to the increasing proliferation of CD4(+)CD25(high) T cells.  相似文献   
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Objective To investigate the effects of soluble factors secreted by acute myeloid leukemia (AML) cells on the phenotypical and functional properties of DCs derived from normal mononuclear cells. Methods Mononuclear cells were cultured with interleukin-4 (IL-4) and granulocyte-macrophage colony-stimulating factor (GM-CSF), in the presence or absence of 24 h culture supernatants from fresh primary AML cells, to generate immature DCs. The maturation of DCs was induced by cytokines IL-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), and prostaglandin-2 (PGE-2). The phenotypic alterations of DCs and DCs-primed CD4 T cells were evaluated using flow cytometry. Precursor frequency (PF) was calculated to monitor the allostimulatory effects of DCs on CD4 and CD8 T cells. ResultsAML cell supernatant-treated DCs showed significantly lower expression of co-stimulatory molecules CD80 and CD86, and reduced response to cytokines IL-1beta, IL-6, TNF-alpha,and PGE-2. The allostimulatory effects of AML cell supernatant-treated DCs on CD4 and CD8 T cells were significantly lower than those of normal mature DCs [PF (1.8±0.5)% vs. (5.2±1.6)% for CD4 T cells, (2.1±0.6)% vs. (6.5±2.0)%for CD8 T cells, P<0.01]. These AML supematant-induced DCs could also induce allogeneic CD4 T cells to differentiate into CD4 CD25high T cells, which had immunophenotyping characteristics of regulatory T cells, i.e. they expressed Foxp3 but not active maker CD69. Conclusion This study demonstrates that soluble factors secreted by AML cells can inhibit development and functions of DCs. In addition, AML supematant-induced DCs can induce the generation of CD4 CD25high T cells from CD4 T cells, which may be a mechanism of increased prevalence of CD4 CD25high regulatory T cells and immune dysfunction in AML patients.  相似文献   
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