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51.
​Multicentric osteolysis nodulosis and arthropathy (MONA) is an infrequently described autosomal recessive skeletal dysplasia characterized by progressive osteolysis and arthropathy. Inactivating mutations in MMP2, encoding matrix metalloproteinase‐2, are known to cause this disorder. Fifteen families with mutations in MMP2 have been reported in literature. In this study we screened thirteen individuals from eleven families for MMP2 mutations and identified eight mutations (five novel and three known variants). We characterize the clinical, radiographic and molecular findings in all individuals with molecularly proven MONA from the present cohort and previous reports, and provide a comprehensive review of the MMP2 related disorders. © 2015 Wiley Periodicals, Inc.
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Trichothiodystrophy, non‐photosensitive type 4 (TTD4), is a rare genetic disorder with an autosomal recessive mode of inheritance. It is characterized by coarse and brittle hair, anomalies of the tissues derived from the neuro‐ectoderm (skin, hair, and nails) and intellectual disability. We herein report two male siblings aged 13 and 16 years with TTD4 and a known homozygous pathogenic variant, c.229del [p.(Arg77Glyfs*76)] in exon 1 of MPLKIP (NM_138701.3). We herein highlight the clinical and molecular findings of the first reported case of TTD4 in probands of Indian ethnicity.  相似文献   
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Objective  

To study the outcome of HIV exposed infants in terms of mortality, morbidity, nutritional status and HIV infection status.  相似文献   
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Nifedipine and verapamil (Martin et al. Science 1987;235:899-901) are a class of calcium channel blockers involved in the reversal of chloroquine (CQ) drug resistance in CQ-sensitive Plasmodium spp. Nifedipine alters calcium-dependent functions of macrophages and neutrophils during Plasmodium berghei malaria. However, knowledge of nifedipine-induced immunomodulation of T cell functions during P. berghei malaria is still limited. We investigated the effect of nifedipine on the immune status of splenic T cells during P. berghei malaria. The intracellular calcium levels were determined in the FURA-2A/M loaded T cells by spectrofluorometry. Splenic T cell proliferation, phosphatidylserine (PS) externalization, Fas expression and Bcl2/Bax expression were determined by flow cytometry. We report a significant increase in mean percent parasitemia in nifedipine-treated and P. berghei-infected mice. Although nifedipine treatment alone did not affect the resting state free calcium levels in splenic T cells, the rise in intracellular calcium levels of T cells following P. berghei infection was significantly less in nifedipine-treated mice compared to untreated groups at various parasitemia levels. Antigen-specific splenic T cell proliferation and apoptosis was ablated in nifedipine-treated and untreated groups at various parasitemia levels. The study unequivocally reflects the suppression of P. berghei-specific T cell immune responses by nifedipine.  相似文献   
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Cross-reactive CD8+ T cell epitopes identified in US adolescent minorities   总被引:3,自引:0,他引:3  
Vaccines designed to bring forth CD8+ T cell responses in different racial and ethnic groups will require inclusion of T cell epitopes presented by various MHC class I molecules. This study was designed to identify new CD8+ T cell epitopes in HIV-infected African American and Hispanic youth as well as to determine the frequency of responses to both novel and previously described HIV-1 epitopes in a cohort of racially and ethnically diverse individuals. We found 8 MHC class I-restricted CD8+ T cell epitopes that had not been previously described, another 8 epitopes that were restricted by class I alleles not previously associated with these epitopes, and 8 additional epitopes that have been described previously. In a larger cohort, we demonstrated that 11 (69%) of these 16 newly described immunogens were recognized by individuals of different race or ethnicity. Most HIV-1-specific CD8+ T cell epitopes identified were either novel or restricted by alternative MHC class I alleles. Frequent recognition of several of these CTL epitopes in persons of diverse racial backgrounds bodes well for the development of a broadly reactive HIV-1 vaccine.  相似文献   
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目的观察骨形态蛋白2(BMP-2)在糖尿病肾病(DN)大鼠肾实质内小动脉上的表达及其变化规律,探讨其对糖尿病肾病血管病变的影响。方法设对照组(N组)、DN组两组,建立STZ诱导的DN大鼠模型。茜素红染色观察肾实质内小动脉周围钙盐沉积,并分别采用免疫组化及mRNA原位杂交法检测BMP-2在肾实质内小动脉上的蛋白表达及基因定位。结果 (1)茜素红染色DN组第4~12周时偶见肾内小动脉少许点状红色钙盐沉积,第24周时可见肾实质内小动脉及周围组织有较多红色点片状沉积;N组茜素红染色为阴性。(2)DN组肾实质内小动脉BMP-2蛋白及mRNA在4周时已有表达,随时间延长表达逐渐增强,各时间点均明显高于N组;N组各时间点表达差异无统计学意义。结论 (1)DN大鼠肾内小动脉钙化前即已有BMP-2的表达;(2)BMP-2可能是糖尿病血管钙化的重要转录因子及早期生物学标志之一;(3)肾内小动脉上BMP-2的表达变化可能参与DN进展。  相似文献   
60.
Langerhans cells develop from a lymphoid-committed precursor   总被引:7,自引:3,他引:4       下载免费PDF全文
Anjuère F  del Hoyo GM  Martín P  Ardavín C 《Blood》2000,96(5):1633-1637
Langerhans cells (LCs) are specialized dendritic cells (DCs) strategically located in stratified epithelia, such as those of the skin, oral cavity, pharynx, esophagus, upper airways, urethra, and female reproductive tract, which are exposed to a wide variety of microbial pathogens. LCs play an essential role in the induction of T-lymphocyte responses against viruses, bacteria, and parasites that gain access to those epithelial surfaces, due to their high antigen capture and processing potential and their capacity to present antigen peptides to T cells on migration to the lymph nodes.(1) Although LCs have been classically considered of myeloid origin, recent reports, which demonstrate the existence of lymphoid DCs derived from multipotent lymphoid precursors devoid of myeloid differentiation potential,(2-5) raise the question of the lymphoid or myeloid origin of LCs. The present study shows that mouse lymphoid-committed CD4(low) precursors, with the capacity to generate T cells, B cells, CD8(+) lymphoid DCs, and natural killer cells,(26) also generate epidermal LCs on intravenous transfer, supporting the view that LCs belong to the lymphoid lineage. (Blood. 2000;96:1633-1637)  相似文献   
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