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1.
The Arg753GLn polymorphism of the human toll-like receptor 2 gene in tuberculosis disease. 总被引:16,自引:0,他引:16
A C Ogus B Yoldas T Ozdemir A Uguz S Olcen I Keser M Coskun A Cilli O Yegin 《The European respiratory journal》2004,23(2):219-223
Toll-like receptor 2 (TLR2), a member of the Toll-like receptor family, plays an important role in recognition of, and subsequent immune response activation against, mycobacteria. The genetic polymorphism of TLR2 (arginine to glutamine substitution at residue 753 (Arg753Gln)) has been associated with a negative influence on TLR2 function, which may, in turn, determine the innate host response to mycobacteria. The aim of the present study was to investigate the Arg753Gln single nucleotide polymorphism of the TLR2 gene in tuberculosis (TB) patients compared to healthy controls. A retrospective case/control study was carried out. The Arg753Gln polymorphism of the TLR2 gene was studied in 151 TB patients compared to 116 ethnically and age-matched healthy control subjects. The TLR2 polymorphism (adenine (A) allele) was observed in 17.9 and 7.7% of TB patients and controls, respectively. When the ratios of the three genotypes were compared between the two groups, the AA genotype was found to be more significantly associated with TB. Allele frequencies for guanine (G) and A were found to be 0.95 and 0.05 in the control group and 0.86 and 0.14 in the TB patient group, respectively. The risk of developing TB disease was increased 6.04- and 1.60-fold for carriers of the AA and GA genotypes, respectively. In conclusion, the present data suggest that the arginine to glutamine substitution at residue 753 polymorphism of the Toll-like receptor 2 gene influences the risk of developing tuberculosis. 相似文献
2.
Some 2-methyl-3-triazole-substituted-4(3H)-quinazolinones 3a-f were prepared and tested for their H1- and H2-antihistaminic activities. In addition these compounds are central nervous system depressants and anticonvulsants. 3e shows highly significant decrease of locomotor activity. 相似文献
3.
Researchers usually employ orthogonal arrays or D-optimal designs with little or no attribute overlap in stated-choice surveys. The challenge is to balance statistical efficiency and respondent burden to minimize the overall error in the survey responses. This study examined whether simplifying the choice task, by using a design with more overlap, provides advantages over standard minimum-overlap methods. We administered two designs for eliciting HIV test preferences to split samples. Surveys were undertaken at four HIV testing locations in San Francisco, California. Personal characteristics had different effects on willingness to pay for the two treatments, and gains in statistical efficiency in the minimal-overlap version more than compensated for possible imprecision from increased measurement error. 相似文献
4.
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Two seemingly unrelated events--decentralization of the nursing organization and promotion of nurse executives into patient care services vice presidencies with authority over many departments--prompt the authors to ask the question, "Who is leading the nursing department?" The authors discuss the impact of these trends on the nursing organization and make suggestions for ensuring strong nursing leadership. 相似文献
6.
Ozdemir O 《The Journal of allergy and clinical immunology》2005,116(5):1165-6; author reply 1166-7
7.
In vitro comparisons of induction of perforin (PFP), granzyme B (GRB), production of cytokines, and cell-mediated cytotoxicity by interleukin-2 (IL-2), interleukin-15 (IL-15), or combinational IL-2/IL-15-induced lymphokine-activated killer cells were studied in this study. Whereas IL-2-induction was associated with a decrease in cultured cell population over a 7-day period, IL-15 alone or in combination with IL-2 resulted in significant increase including cytotoxic T lymphocytes and subsets of CD56+ lymphocytes, particularly cytokine-induced killer and cytolytic natural killer-T lymphocytes. The overall PFP, GRB, and tumor necrosis factor-alpha expression in different subtypes were also significantly higher with IL-15 alone or in combination with IL-2 induction with resultant superior cytotoxicity compared to IL-2 treatment. There was no significant advantage of addition of IL-2 over IL-15 induction. These results offer further information on the cytotoxic potency of these cytokines and their mechanisms of action implicating potential use of IL-15 as part of cytokine adoptive immunotherapy. 相似文献
8.
Retroperitoneal cystic lymphangioma is a rare congenital malformation. The majority of lymphangiomas are present at birth and nearly all present before the age of two years. We report a case of giant cystic retroperitoneal lymphangioma in a patient who first presented with symptoms at the age of 7, underwent surgery, and who then suffered a recurrent mass 11 years later. 相似文献
9.
Robert R Nail S Marot-Leblond A Cottin J Miegeville M Quenouillere S Mahaza C Senet JM 《Infection and immunity》2000,68(2):570-576
The in vivo interactions of platelets with Candida species yeast cells were investigated in a murine model. Mice were injected intravenously via the lateral caudal vein, and blood drawn by periorbital puncture was collected in phosphate-buffered saline-formaldehyde to avoid in vitro platelet activation. The study of the clearance of blastoconidia of Candida albicans and Candida glabrata showed that these cells disappeared quickly from the bloodstream. Microscopic observation of blood samples, stained by Calcofluor white or May Grunwald Giemsa, demonstrated the rapid attachment of platelets to fungal elements of all the Candida spp. tested. The attachment of murine platelets to C. albicans cells, observed by scanning electron microscopy, revealed morphological changes. The platelets lost their discoid shape, generated pseudopodia, and flattened against the yeast cells. The reversibility of platelet binding to C. albicans by chelating agents suggests a cation-dependent link. In contrast, the fixation of C. glabrata and Candida tropicalis was not modified by chelating agents. The mechanisms involved in the in vivo adherence of platelets to Candida cells may therefore differ according to the species of Candida. 相似文献
10.
Novel ENAM mutation responsible for autosomal recessive amelogenesis imperfecta and localised enamel defects 总被引:4,自引:0,他引:4 下载免费PDF全文
Hart TC Hart PS Gorry MC Michalec MD Ryu OH Uygur C Ozdemir D Firatli S Aren G Firatli E 《Journal of medical genetics》2003,40(12):900-906
The genetic basis of non-syndromic autosomal recessive forms of amelogenesis imperfecta (AI) is unknown. To evaluate five candidate genes for an aetiological role in AI. In this study 20 consanguineous families with AI were identified in whom probands suggested autosomal recessive transmission. Family members were genotyped for genetic markers spanning five candidate genes: AMBN and ENAM (4q13.3), TUFT1 (1q21), MMP20 (11q22.3-q23), and KLK4 (19q13). Genotype data were evaluated to identify homozygosity in affected individuals. Mutational analysis was by genomic sequencing. Homozygosity linkage studies were consistent for localisation of an AI locus in three families to the chromosome 4q region containing the ENAM gene. ENAM sequence analysis in families identified a 2 bp insertion mutation that introduced a premature stop codon in exon 10. All three probands were homozygous for the same g.13185_13186insAG mutation. These probands presented with a generalised hypoplastic AI phenotype and a class II openbite malocclusion. All heterozygous carriers of the g.13185_13186insAG mutation had localised hypoplastic enamel pitting defects, but none had AI or openbite. The phenotype associated with the g.13185_13186insAG ENAM mutation is dose dependent such that ARAI with openbite malocclusion segregates as a recessive trait, and enamel pitting as a dominant trait. 相似文献