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41.
Oindrila Raha Biswanath Sarkar Bhaskar VKS Lakkakula Veerraju Pasumarthy Sudhakar Godi Subhankar Chowdhury Pradip Raychaudhuri Raghavendra Rao Vadlamudi 《Journal of biomedical science》2013,20(1):12
Background
Several studies have demonstrated a fundamental role for the HLA in the susceptibility of, or protection to, type 1 diabetes mellitus (T1DM). However, this has not been adequately studied in Asian Indian populations. To assess the frequency of HLA class II (DPA1, DPB1, DQA1, DQB1 and DRB1) associated to susceptibility or protection toT1DM in a Bengali population of India with diabetes.Results
Single nucleotide polymorphism study. The HLA genotyping was performed by a polymerase chain reaction followed by their HLA-DP, DQ, and DRB1 genotypes and haplotypes by sequencing method. The results are studied by Plink software. The χ2 tests were used for the inferential statistics. To our knowledge, this study is the first of a kind which has attempted to check the HLA association with T1DM by SNPs analysis. The study recruited 151 patients with T1DM and same number of ethno-linguistic, sex matched non-diabetic controls. The present study found a significant SNP rs7990 of HLA-DQA1 (p = 0.009) negative correlation, again indicating that risk from HLA is considerably more with T1DM.Conclusions
This study demonstrates that the HLA class-II alleles play a major role in genetic basis of T1DM. 相似文献42.
《Electromagnetic biology and medicine》2013,32(2):161-168
Cultured fibroblasts isolated from murine livers by tissue trypsinization were exposed to a static magnetic field (0.490 T) and to extremely low frequency (ELF) magnetic field (50 Hz, 0.020 T). The cultures were exposed to magnetic fields on four consecutive days for exposure times of 2, 4, 8, 16, 32, and 64 min. After such exposures and obtaining of fibroblast subcellular fractions, lipid peroxidation product—malondialdehyde (MDA) was measured. Increased peroxidation of fibroblasts' membrane structures exposed to an ELF magnetic field was observed in subcellular fractions—microsomal, mitochondrial, and nuclear. No changes in peroxidation of membrane structures were found in fibroblasts exposed to a static magnetic field. 相似文献
43.
Katherine E. Eisen Amy C. Wruck Monica A. Geber 《Evolution; international journal of organic evolution》2020,74(8):1682-1698
Although the evolution and diversification of flowers is often attributed to pollinator-mediated selection, interactions between co-occurring plant species can alter patterns of selection mediated by pollinators and other agents. The extent to which both floral density and congeneric species richness affect patterns of net and pollinator-mediated selection on multiple co-occurring species in a community is unknown and is likely to depend on whether co-occurring plants experience competition or facilitation for reproduction. We conducted an observational study of selection on four species of Clarkia (Onagraceae) and tested for pollinator-mediated selection on two Clarkia species in communities differing in congeneric species richness and local floral density. When selection varied with community context, selection was generally stronger in communities with fewer species, where local conspecific floral density was higher, and where local heterospecific floral density was lower. These patterns suggest that intraspecific competition at high densities and interspecific competition at low densities may affect the evolution of floral traits. However, selection on floral traits was not pollinator mediated in Clarkia cylindrica or Clarkia xantiana, despite variation in pollinator visitation and the extent of pollen limitation across communities for C. cylindrica. As such, interactions between co-occurring species may alter patterns of selection mediated by abiotic agents of selection. 相似文献
44.
Wei-Bin Yang Hai-Lin Wang Jian-Ting Mao Zhen Chen Jin-Wei Xu Lian-Hong Wang Min Xu Xin Zhang 《Journal of cellular physiology》2020,235(12):9370-9377
The aim is to investigate the correlation between computed tomography (CT) features and insulin resistance levels in patients with type 2 diabetes mellitus (T2DM) complicated with primary pulmonary tuberculosis (PTB). Nearly, 268 untreated PTB patients complicated with T2DM were divided into two groups according to the optimal cutoff value of HOMA-IR score for the Chinese population: HOMA-IR ≤ 2.69 (Group I: 74 patients), >2.69 (Group II: 194 patients). The basic characteristics and changes of CT manifestations were analyzed. In the two groups, the detection rate of large segmented leafy shadow was 39.2% and 78.9%; the air bronchogram sign detection rate was 40.5% and 80.9%; the discovery rate of mouth-eaten cavity was 33.8% and 73.7%; the thin-walled cavity detection rate was 2.7% and 16.0%; the rate of multiple cavities was 35.1% and 69.6%; and bronchial tuberculosis was found in 4.1% and 35.6%, respectively. The detection rates of lesions in Group II were significantly higher than in Group I (p < .05). HOMA-IR was found independently associated with large segmented leafy shadow, air bronchial sign, thin-walled cavity, and bronchial tuberculosis. The level of insulin resistance can effectively reflect the severity of PTB patients with T2DM. CT scan can directly provide image information in clinics. These two examinations can guide clinicians to accurately formulate subsequent treatment plans. 相似文献
45.
46.
Genetic polymorphisms of glutathione S-transferases (GSTs) and type 2 diabetes mellitus (T2DM) risk have been widely studied, however, the results were somewhat conflicting. To evaluate the association of GSTs (GSTM1, GSTT1 and GSTP1) gene polymorphisms with T2DM, a meta-analysis was performed before October, 2012. ORs were pooled according to random-effects model. There were a total of 1354/1666 (n = 9) cases/controls (studies) for GSTM1, 1271/1470 (n = 8) for GSTT1, and 1205/1250 (n = 7) for GSTM1. There were significant associations between GSTM1 polymorphism, GSTT1 polymorphism and T2DM in the contrast of present genotype vs. null genotype, with pooled OR = 1.99 (95%CI = 1.46–2.71) and OR = 1.61 (95%CI = 1.19–2.17), respectively. Yet no significant association of GSTP1 polymorphism and T2DM was showed. When stratified by ethnicity, the significant associations were also existed in Asians for GSTM1 and GSTT1, but not GSTP1. No publication bias but some extent of heterogeneity was observed. Finally, the accumulated evidence proved the obvious associations of GSTM1 and GSTT1 polymorphisms with an increased risk of T2DM. 相似文献
47.
Marijana Popović Hadžija Marina Korolija Nikolina Jemin Iva Pavković Pajica Pavković Edita Pape Medvidović Mirko Hadžija 《Gene》2013
Genetic variants of IL-18 and IL-12B may be important in immunoregulatory abnormalities, observed in the patients with Type 1 diabetes mellitus (T1DM), that contribute to individual differences in response to a treatment. Therefore, we examined the significance of IL-18-137G/C, IL-18-607C/A, and IL-12B A/C polymorphisms in Croatians (187 patients, 236 controls), not only as factors that contribute to susceptibility to T1DM, but also as determinants of the clinical presentation of disease. 相似文献
48.
D. Jeya Sundara Sharmila K. Veluraja 《Journal of biomolecular structure & dynamics》2013,31(6):641-656
Abstract Molecular mechanics and molecular dynamics studies are performed to investigate the conformational preference of cell surface higher gangliosides (GT1A and GT1B) and their interaction with Cholera Toxin. The water mediated hydrogen bonding network exists between sugar residues in gangliosides. An integrated molecular modeling, molecular mechanics, and molecular dynamics calculation of cholera toxin complexed with GT1A and GT1B reveal that, the active site of cholera toxin can accommodate these higher gangliosides. Direct and water mediated hydrogen bonding interactions stabilize these binding modes and play an essential role in defining the order of specificity for different higher ganglioside towards cholera toxin. This study identifies that the binding site of cholera toxin is shallow and can accommodate a maximum of two NeuNAc residues. The NeuNAc binding site of cholera toxin may be crucial for the design of inhibitors that can prevent the infection of cholera. 相似文献
49.
Marijke de Jong-Brink H. M. Koop W. F. de Roos J. M. Bergamin-Sassen 《Invertebrate reproduction & development.》2013,57(4):207-219
The secretory activity of the albumen gland of the freshwater snail Lymnaea stagnalis was studied morphometrically (both at the light- and at the electron-microscope level) and biochemically under the following experimental conditions: (1) glandular tissue was implanted into acceptor snails and the glandular activity of the implants was compared to that of the glands of the donors and acceptors; (2) glandular activity was measured at various periods after oviposition; and (3) the activity was measured during a 24 h cycle (diurnal activity). The results indicate that cellular release of secretion material is regulated by a nervous mechanism, whereas synthetic activity is under hormonal control. 相似文献
50.
Adriana Simionescu-Bankston Giovanna Leoni Yanru Wang Peter P. Pham Arivudainambi Ramalingam James B. DuHadaway Victor Faundez Asma Nusrat George C. Prendergast Grace K. Pavlath 《Developmental biology》2013
Actin dynamics are necessary at multiple steps in the formation of multinucleated muscle cells. BAR domain proteins can regulate actin dynamics in several cell types, but have been little studied in skeletal muscle. Here, we identify novel functions for the N-BAR domain protein, Bridging integrator 3 (Bin3), during myogenesis in mice. Bin3 plays an important role in regulating myofiber size in vitro and in vivo. During early myogenesis, Bin3 promotes migration of differentiated muscle cells, where it colocalizes with F-actin in lamellipodia. In addition, Bin3 forms a complex with Rac1 and Cdc42, Rho GTPases involved in actin polymerization, which are known to be essential for myotube formation. Importantly, a Bin3-dependent pathway is a major regulator of Rac1 and Cdc42 activity in differentiated muscle cells. Overall, these data classify N-BAR domain proteins as novel regulators of actin-dependent processes in myogenesis, and further implicate BAR domain proteins in muscle growth and repair. 相似文献