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951.
Association of HLA genes with ankylosing spondylitis in Han population of eastern China 总被引:1,自引:0,他引:1
Fang M Chen R Cai Q Duan S Lv K Cheng N Sun S 《Scandinavian journal of immunology》2007,65(6):559-566
Ankylosing spondylitis (AS) is a chronic inflammatory disorder with a multifactorial genetic basis. HLA-B27 was reported with the greatest susceptibility to AS but did not act alone. The aim of this study was to search for other gene(s) associated with AS independently of HLA-B27 using 13 microsatellite markers spanning 1.5 Mb from locus TAP1 to HLA-Cw and a single-nucleotide polymorphism marker within NFkappaBIL1 gene promoter. Genotyping for microsatellites was performed in 175 AS patients of eastern Chinese and 219 ethnically matched healthy controls using polymerase chain reaction with fluorescence-labelled primers, whereas the SNP marker was genotyped by direct DNA sequencing. Allele as well as haplotype frequencies were compared between cases and controls, and a linkage disequilibrium analysis was performed to estimate the LD relationship between the candidate regions. The frequencies of alleles D6S2811*128, STR_MICA*A5.1 and D6S2672*109, as well as haplotypes D6S2811*128-D6S2927*213-D6S2810*340, D6S2927* 221-D6S2810*350-MICA*A5.1, and D6S2810*350-MICA*A5.1-D6S2800* 136 were significantly increased in B27-positive AS patients when compared with B27-positive controls. The results indicated that there may be other gene(s) within the HLA region, especially around locus HLA-B or HLA-Cw, with susceptibility to AS independently of HLA-B27. 相似文献
952.
953.
Norris EH Uryu K Leight S Giasson BI Trojanowski JQ Lee VM 《The American journal of pathology》2007,170(2):658-666
The factors initiating or contributing to the pathogenesis of Parkinson's disease and related neurodegenerative synucleinopathies are still largely unclear, but environmental factors such as pesticides have been implicated. In this study, A53T mutant human alpha-synuclein transgenic mice (M83), which develop alpha-synuclein neuropathology, were treated with the pesticides paraquat and maneb (either singly or together), and their effects were analyzed. Immunohistochemical and biochemical analyses showed that chronic treatment of M83 transgenic mice with both pesticides (but not with either pesticide alone) drastically increased neuronal alpha-synuclein pathology throughout the central nervous system including the hippocampus, cerebellum, and sensory and auditory cortices. alpha-Synuclein-associated mitochondrial degeneration was observed in M83 but not in wild-type alpha-synuclein transgenic mice. Because alpha-synuclein inclusions accumulated in pesticide-exposed M83 transgenic mice without a motor phenotype, we conclude that alpha-synuclein aggregate formation precedes disease onset. These studies support the notion that environmental factors causing nitrative damage are closely linked to mechanisms underlying the formation of alpha-synuclein pathologies and the onset of Parkinson's-like neurodegeneration. 相似文献
954.
TDP-43 in familial and sporadic frontotemporal lobar degeneration with ubiquitin inclusions 总被引:23,自引:0,他引:23
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Cairns NJ Neumann M Bigio EH Holm IE Troost D Hatanpaa KJ Foong C White CL Schneider JA Kretzschmar HA Carter D Taylor-Reinwald L Paulsmeyer K Strider J Gitcho M Goate AM Morris JC Mishra M Kwong LK Stieber A Xu Y Forman MS Trojanowski JQ Lee VM Mackenzie IR 《The American journal of pathology》2007,171(1):227-240
TAR DNA-binding protein 43 (TDP-43) is a major pathological protein of sporadic and familial frontotemporal lobar degeneration with ubiquitin-positive, tau-negative inclusions (FTLD-U) with or without motor neuron disease (MND). Thus, TDP-43 defines a novel class of neurodegenerative diseases called TDP-43 proteinopathies. We performed ubiquitin and TDP-43 immunohistochemistry on 193 cases of familial and sporadic FTLD with or without MND. On selected cases, immunoelectron microscopy and biochemistry were performed. Clinically defined frontotemporal dementias (FTDs) included four groups: 1) familial FTD with mutations in progranulin (n = 36), valosin-containing protein (n = 5), charged multivesicular body protein 2B (n = 4), and linked to chromosome 9p (n = 7); 2) familial cases of FTD with unknown gene association (n = 29); 3) sporadic FTD (n = 72); and 4) familial and sporadic FTD with MND (n = 40). Our studies confirm that the spectrum of TDP-43 proteinopathies includes most cases of sporadic and familial FTLD-U with and without MND and expand this disease spectrum to include reported families with FTD linked to chromosome 9p but not FTD with charged multivesicular body protein 2B mutations. Thus, despite significant clinical, genetic, and neuropathological heterogeneity of FTLD-U, TDP-43 is a common pathological substrate underlying a large subset of these disorders, thereby implicating TDP-43 in novel and unifying mechanisms of FTLD pathogenesis. 相似文献
955.
Li Y Chang Q Rubin BP Fletcher CD Morgan TW Mentzer SJ Sugarbaker DJ Fletcher JA Xiao S 《The Journal of pathology》2007,211(5):550-554
Solitary fibrous tumours (SFTs) are known to overexpress insulin-like growth factor 2 (IGF-2). The down-stream oncogenic pathways of IGF-2, however, are not clear. Here we report uniform activation of the insulin receptor (IR) pathway in SFTs, which are mesenchymal tumours frequently associated with hypoglycaemia. Whereas the IR and its downstream signalling pathways were constitutively activated in SFTs, insulin-like growth factor 1 receptor (IGF-1R) was not expressed in these tumours. We also find that SFT cells secrete IGF-2 and proliferate in serum-free medium, consistent with an IGF-2/IR autocrine loop. The aetiological relevance of IGF-2 is supported by expression of IR-A, the IR isoform with high affinity for IGF-2, in all SFTs. Our studies suggest that IR activation plays an oncogenic role in SFTs. 相似文献
956.
Duan B Croker BP Morel L 《Laboratory investigation; a journal of technical methods and pathology》2007,87(1):14-28
The NZM2410 and NZM TAN (TAN) are two of 27 inbred strains derived from an intercross between the NZW and NZB strains. NZM2410 mice develop a highly penetrant lupus nephritis mediated by three susceptibility loci, Sle1, Sle2 and Sle3. These three loci have been combined on a C57BL/6 background in a triple congenic strain that reconstitutes the NZM2410 autoimmune phenotype. Remarkably, inspite of the presence of Sle1, Sle2 and Sle3, TAN mice display a mild autoimmune phenotype reminiscent of NZW. Contrary to the lupus-prone strains, the majority of TAN CD4(+) T cells are in a na?ve-inactivated stage. TAN mice show B-cell developmental abnormalities similar to lupus-prone mice, such an accumulation of transitional T1 cells and peritoneal B-1a cells. TAN mice show, however, a unique expansion of the splenic marginal zone, in which B cells express high levels of CD5 and CD9, fail to migrate to the follicles in response to LPS, and show sub-optimal binding of T-independent type 2 antigens. Therefore, TAN mice present a functional silencing of marginal zone B cells, which have been previously implicated with autoimmune process. The TAN strain thus provides a novel model for the analysis of the genetic determinants of B-cell autoreactivity. 相似文献
957.
群体感应系统(quorum sensing system, QS)是一种微生物细胞与细胞间的交流系统。铜绿假单胞菌是该系统的典型代表,可调控细菌产生对抗生素的耐药、形成生物膜、产生毒力因子,并且减弱宿主的免疫应答。群体感应系统抑制剂(quorum sensing inhibitors, QSIs)在不影响细菌生长的前提下可降低细菌的毒性,且增强细菌生物膜对抗生素治疗的敏感性,这些特点使QSIs成为目前抗感染领域的研发热点。本文就铜绿假单胞菌的群体感应系统及QSIs的研究进展进行了综述。 相似文献
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