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991.
Yan‐Yan Li Wei Gao Si‐Si Pang Xiao‐Yan Min Zhi‐Jian Yang Hui Wang Xin‐Zheng Lu Lian‐Sheng Wang Xiang‐Ming Wang Yun Qian Chuan‐Wei Zhou Jun Wu Ai‐Ling Chen 《Journal of cellular and molecular medicine》2014,18(5):929-937
Transporter associated with antigen processing 1 (TAP1) I333V gene polymorphism has been suggested to be associated with type 1 diabetes mellitus (T1DM) susceptibility. However, the results from individual studies are inconsistent. To explore the association of TAP1 I333V gene polymorphisms with T1DM, a meta‐analysis involving 2246 cases from 13 individual studies was conducted. The pooled odd ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were evaluated by a fixed‐effect model. A significant relationship was observed between TAP1 I333V gene polymorphism and T1DM in allelic (OR: 1.35, 95% CI: 1.08–1.68, P = 0.007), dominant (OR: 1.462, 95% CI: 1.094–1.955, P = 0.010), homozygous (OR: 1.725, 95% CI: 1.082–2.752, P = 0.022), heterozygous (OR: 1.430, 95% CI: 1.048–1.951, P = 0.024) and additive (OR: 1.348, 95% CI: 1.084–1.676, P = 0.007) genetic models. No significant association between TAP1 I333V gene polymorphism and T1DM was detected in a recessive genetic model (OR: 1.384, 95% CI: 0.743–2.579, P = 0.306) in the entire population, especially among Caucasians. No significant association between them was found in an Asian or African population. TAP1 I333V gene polymorphism was significantly associated with increased T1DM risk. V allele carriers might be predisposed to T1DM susceptibility. 相似文献
992.
Shangqian Wang Wei Wang Yang Xu Min Tang Jianzheng Fang Hongyong Sun Yangyang Sun Meijuan Gu Zhili Liu Zhaoxia Zhang Faxi Lin Ting Wu Ninghong Song Zengjun Wang Wei Zhang Changjun Yin 《Proteomics》2014,14(2-3):298-310
Human sperm cryopreservation in assisted reproductive technology is the only proven method that enables infertile men to father their own children. However, freezing and thawing reduces spermatozoon motility, viability, and fertilizing ability. An association between dysfunctional spermatozoa due to cryoinjury and protein changes has not been established. We investigated through proteomic analysis the differential protein characteristics between freeze‐thawed and fresh sperm samples obtained from nine normozoospermic donors. Twenty‐seven proteins differed in abundance between the two groups, and results were verified for four proteins via Western blot and immunofluorescent staining. These proteins are putatively involved in sperm motility, viability, acrosomal integrity, ATP and isocitrate content, mitochondrial membrane potential, capacitation, acrosome reaction, and intracellular calcium concentration. These marked differences suggest that dysfunctional spermatozoon after cryopreservation may be due to protein degradation and protein phosphorylation. 相似文献
993.
Fengyan Xu Guiqin Zhou Shaoli Han Weiguang Yuan Shuang Chen Zhenkun Fu Dalin Li Hua Zhang Dianjun Li Da Pang 《PloS one》2014,9(7)
Background
The interaction of tumor necrosis factor-α (TNF-α) with its receptors: TNFRSF1A and TNFRSF1B is critical for the promotion of tumor growth, invasion and metastasis. To better understand the roles of single nucleotide polymorphisms (SNPs) in the TNF-α, TNFRSF1A and TNFRSF1B genes in the development of breast cancer, we explored the associations between SNPs in these three genes and breast cancer susceptibility in northeast Chinese Han women.Methodology/Principal Findings
This case-control study was conducted among 1016 breast cancer patients and 806 age-matched healthy controls. Seven SNPs in the TNF-α (rs1800629, rs361525), TNFRSF1A (rs767455, rs4149577 and rs1800693) and TNFRSF1B (rs1061622 and rs1061624) genes were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. In TNFRSF1B, the rs1061622 GT genotype and the G allele conferred a reduced susceptibility to breast cancer (P = 0.000662, OR = 0.706, 95% CI: 0.578–0.863; P = 0.002, OR = 0.769, 95% CI; 0.654–0.905, respectively). Moreover, the AG genotype, the AA genotype and the A allele in rs1061624 conferred an increased risk of breast cancer (P = 0.007, OR = 1.470, 95% CI:1.112–1.943; P = 0.00109, OR = 1.405 95% CI:1.145–1.724; P = 0.001, OR = 1.248 95% CI:1.092–1.426, respectively). These two SNPs also had associations with breast cancer risk under the dominant model. In haplotype analysis, the CTA (rs767455 C-rs4149577 T-rs1800693 A) haplotype in TNFRSF1A and the TA (rs1061622 T-rs1061624 A) haplotype in TNFRSF1B had higher frequencies in breast cancer patients (P = 0.00324; P = 0.000370, respectively), but the frequency of GG (rs1061622 G-rs1061624 G) haplotype in TNFRSF1B was lower in breast cancer patients (P = 0.000251). The associations of the three haplotypes remained significant after correcting for multiple testing. In addition, significant associations were also observed between TNFRSF1A polymorphisms and lymph node metastasis, P53, estrogen receptor (ER) and progesterone receptor (PR) statuses.Conclusions
Our results suggest that rs1061622 and rs1061624 in TNFRSF1B may affect breast cancer risk, and SNPs in TNFRSF1A are associated with the clinical features of breast cancer. 相似文献994.
Jeffrey B Driban Lori Lyn Price Grace H Lo Jincheng Pang David J Hunter Eric Miller Robert J Ward Charles B Eaton John A Lynch Timothy E McAlindon 《Arthritis research & therapy》2013,15(5):R112
Introduction
Bone marrow lesion (BML) size may be an important imaging biomarker for osteoarthritis-related clinical trials and reducing BML size may be an important therapeutic goal. However, data on the interrelationships between BML size, pain, and structural progression are inconsistent and rarely examined in the same cohort. Therefore, we evaluated the cross-sectional and longitudinal associations of BML volume with knee pain and joint space narrowing (JSN).Methods
A BML volume assessment was performed on magnetic resonance images of the knee collected at the 24- and 48-month Osteoarthritis Initiative visits from a convenience sample of 404 participants in the progression cohort. During the same visits, knee pain was assessed with WOMAC pain scores and knee radiographs were acquired and scored for JSN. BML volume was summed to generate a total knee volume and an index tibiofemoral compartment volume (compartment with greater baseline JSN). Primary analyses included multiple linear regressions (outcome = pain, predictor = total knee BML volume) and logistic regressions (outcome = JSN, predictor = index tibiofemoral compartment BML volume).Results
This sample was 49% female with a mean age of 63 (9.2 standard deviation (SD)) years, and 71% had radiographic osteoarthritis in the study knee. Larger baseline BMLs were associated with greater baseline knee pain (P = 0.01), the presence of JSN at baseline (odds ratio (OR) = 1.50, 95% confidence interval (CI) = 1.23 to 1.83), and JSN progression (OR = 1.27, 95%CI = 1.11 to 1.46). Changes in total knee BML volume had a positive association with changes in knee pain severity (P = 0.004) and this association may be driven by knees that were progressing from no or small baseline BMLs to larger BMLs. In contrast, we found no linear positive relationship between BML volume change and JSN progression. Instead, regression of medial tibiofemoral BML volume was associated with JSN progression compared to knees with no or minimal changes in BML volume (OR = 3.36, 95%CI = 1.55 to 7.28). However, follow-up analyses indicated that the association between JSN progression and BML volume change may primarily be influenced by baseline BML volume.Conclusion
Large baseline BMLs are associated with greater baseline knee pain, the presence of JSN at baseline, and disease progression. Additionally, BML regression is associated with decreased knee pain but not a reduced risk of concurrent JSN progression. 相似文献995.
生物钟现象是一种普遍存在于生物界细胞的内源节律性保持机制。生物钟机制的存在可以使生物体的代谢行为产生并维持以24 h为周期的昼夜节律,从而更好地适应于地球自转所产生的环境条件昼夜间节律性变化。蓝藻是目前生物钟分子机制研究中的模式生物,其依赖于k ai基因家族成员的核心生物钟调控模式已经被众多研究者详细阐明。蓝藻生物钟的核心振荡器是由蓝藻k aiA/B/C的编码产物来调控的,Kai蛋白的表达模式具有节律性。KaiC蛋白磷酸化状态的节律性循环及输入、输出途径相关组成蛋白的翻译后修饰状态节律性循环共同组成其反馈回路,负责维持生物钟节律性振荡的持续进行并与环境周期保持同步。传统的蓝藻生物钟分子机制模型认为,节律性表达基因翻译产物的转录/翻译负反馈抑制环是生物节律性维持和输出的关键。遗憾的是,在其它物种生物钟分子机制研究中未发现由kai基因家族成员同源基因组成的节律性标签,这表明以k aiA/B/C为核心振荡器的生物钟系统并不是一种跨物种保守的生物钟系统。近期,人们发现非转录/翻译依赖的振荡器(NTO)也具有成为生物节律性产生和维持的“源动力”的可能。过氧化物氧化还原酶(PRX)氧化还原状态节律性是第一种被报道的跨物种保守的NTO节律性标签,这也日渐成为蓝藻生物钟分子机制研究新的热点。 相似文献
996.
997.
998.
Effects of light intensity on the epiphytic bacterial community of sporelings of Saccharina japonica
Journal of Applied Phycology - In the artificial hatchery of Saccharina japonica, sporelings suffer from various diseases caused by improper irradiance. On the other hand, the outbreaks of diseases... 相似文献
999.
1000.