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111.
112.
The aim of our meta-analysis was to quantitatively summarize the association of TYK2 gene polymorphisms with autoimmune and inflammatory diseases. 11 studies that included data from 21497 cases and 22647 controls were identified. OR was used as a measure of the effect of the association in a fixed/random effect model. Meta-analysis was performed for six TYK2 gene polymorphisms (rs34536443, rs2304256, rs280523, rs280519, rs12720270 and rs12720356). Significant association was found in rs34536443 (C versus G: OR = 0.76, 95% CI = 0.69–0.84, P < 0.00001; GC + CC versus GG: OR = 0.78, 95% CI = 0.68–0.90, P = 0.0005; CC versus GG + GC: OR = 0.76, 95% CI = 0.28–2.05, P = 0.58; CC versus GG: OR = 0.74, 95% CI = 0.27–2.02, P = 0.56; GC versus GG: OR = 0.78, 95% CI = 0.68–0.90, P = 0.0006) and rs2304256 (A versus C: OR = 0.78, 95% CI = 0.70–0.87, P < 0.0001; CA + AA versus CC: OR = 0.69, 95% CI = 0.59–0.81, P < 0.0001; AA versus CC + CA: OR = 0.75, 95% CI = 0.66–1.00, P = 0.05; AA versus CC: OR = 0.64, 95% CI = 0.47–0.86, P = 0.003; CA versus CC: OR = 0.70, 95% CI = 0.60–0.83, P < 0.0001) in TYK2 gene, but not for the other polymorphisms (rs280523, rs280519, rs12720270, and rs12720356). This meta-analysis demonstrates that autoimmune and inflammatory diseases is associated with TYK2 gene rs34536443 and rs2304256 polymorphisms, but not rs280523, rs280519, rs12720270 and rs12720356.  相似文献   
113.
Ponatinib (AP24534) was previously identified as a pan-BCR-ABL inhibitor that potently inhibits the T315I gatekeeper mutant, and has advanced into clinical development for the treatment of refractory or resistant CML. In this study, we explored a novel series of five and six membered monocycles as alternate hinge-binding templates to replace the 6,5-fused imidazopyridazine core of ponatinib. Like ponatinib, these monocycles are tethered to pendant toluanilides via an ethynyl linker. Several compounds in this series displayed excellent in vitro potency against both native BCR-ABL and the T315I mutant. Notably, a subset of inhibitors exhibited desirable PK and were orally active in a mouse model of T315I-driven CML.  相似文献   
114.
Chicken cystatin (cC) mutant I66Q is located in the hydrophobic core of the protein and increases the propensity for amyloid formation. Here, we demonstrate that under physiological conditions, the replacement of Ile with the Gln in the I66Q mutant increases the susceptibility for the disulfide bond Cys71–Cys81 to be reduced when compared to the wild type (WT) cC. Molecular dynamics (MD) simulations under conditions favoring cC amyloid fibril formation are in agreement with the experimental results. MD simulations were also performed to investigate the impact of disrupting the Cys71–Cys81 disulfide bond on the conformational stability of cC at the atomic level, and highlighted major disruption to the cC appendant structure. Domain swapping and extensive unfolding has been proposed as one of the possible mechanisms initiating amyloid fibril formation by cystatin. Our in silico studies suggest that disulfide bond formation between residues Cys95 and Cys115 is necessary to maintain conformational stability of the I66Q mutant following breakage of the Cys71–Cys81 disulfide bridge. Subsequent breakage of disulfide bond Cys95–Cys115 resulted in large structural destabilization of the I66Q mutant, which increased the α–β interface distance and expanded the hydrophobic core. These experimental and computational studies provide molecular-level insight into the relationship between disulfide bond formation and progressive unfolding of amyloidogenic cC mutant I66Q.

An animated Interactive 3D Complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:JBSD:23  相似文献   
115.
[目的]观察比较鼠脑复壮前后狂犬病毒的形态变化,并观察病毒感染BHK-21细胞后不同时间的形态发生情况.[方法]以保存时间较长的SRV9毒株为原始材料,经乳鼠脑传代复壮后接种BHK-21细胞,浓缩、纯化后观察.[结果](1)未经复壮的病毒中DI粒子占较高比例,典型粒子只占少数,而复壮后典型粒子所占比例升高到病毒粒子总数的90%.(2)感染24h后在细胞浆内可以观察到典型病毒粒子,其数量随着培养时间的延长而增加.带毒传代之后的培养过程中细胞内病毒数量增加不明显.(3)病毒可以在细胞内的空泡膜表面以多种方式成堆出芽.[结论](1)鼠脑复壮可恢复狂犬病毒中典型粒子所占比例.(2)带毒传代1~2次时为狂犬病毒收获的最佳时机.(3)本研究为狂犬病毒的装配机制补充了数据.  相似文献   
116.
王曦  张磊  周士胜  邹伟 《微生物学报》2008,24(3):521-524
介绍了一种如何合理的利用蛋白质免疫沉淀和蛋白质免疫印迹相结合的方法检测大鼠心肌细胞钾离子通道蛋白Kv1.2和Kv1.5的表达与活化水平。实验结果表明, 与单独利用免疫印迹的方法相比较, 本实验是对钾离子通道蛋白及其它亚家族的钾通道蛋白磷酸化表达水平检测方法的一种优化, 从而获得一套可行、简单、合理的实验方案, 同时也提高了检测的准确性, 敏感性及特异性。  相似文献   
117.
本工作采用无血清原供培养大鼠肝细胞法,观察了重组人肝细胞生长因子对四氯化碳致大鼠肝细胞损伤的保护作用。结果表明,r-hHGF对CCl4染毒肝细胞有明显的保护作用。r-hHGF保护组较CCl4染毒组细胞存活率显著升高,细胞内丙氨酸转氨酶,钾离子漏出明显降低。  相似文献   
118.
The aim of this study was to establish plasma cytokine/chemokine profiles in patients with 3 different presentations of active tuberculosis (TB), compared to the profiles observed in bacillus Calmette-Guérin (BCG)-vaccinated healthy individuals and patients with other pulmonary diseases (non-TB patients). To this end, plasma samples were collected from 151 TB patients including 68 pulmonary TB (PTB), 43 endobronchial TB, and 40 tuberculosis pleurisy (TP) patients, as well as 107 no-TB cases including 26 non-TB patients and 81 BCG-vaccinated healthy controls. A liquid array-based multiplexed immunoassay was used to screen plasma samples for 20 distinct cytokines and chemokines. Multinomial logistic regression was used to analyze associations between cytokines/chemokines and TB/non-TB patients. Compared to our findings with the no-TB donors, the median plasma levels of the proinflammatory cytokines/chemokines TNF-α, IL-6, IP-10, IFN-γ, and MIP-1β were significantly elevated in TB patients, suggesting their potential use as biomarkers for diagnosing TB patients. Further comparisons with healthy donors showed that only the median TNF-α plasma level was highly produced in the plasma of all 3 types of TB patients. Plasma IL-6 production was higher only in TP patients, while the plasma levels of IP-10, IFN-γ, and MIP-1β were markedly enhanced in both PTB and TP patients. Unexpectedly, among the above cytokines/chemokines, MIP-1β was also highly expressed in non-TB patients, compared with healthy donors. Our results suggested that TNF-α may be an ideal biomarker for diagnosing the 3 forms of TB presentation, while the other factors (IL-6, IP-10, MCP-1, and IFN-γ) can potentially facilitate differential diagnosis for the 3 TB presentation types. Further characterization of immune responses associated with different types of TB diseases will provide a basis for developing novel TB diagnostics.  相似文献   
119.
Myeloperoxidase (MPO), a heme protein existing in neutrophil and monocyte, is implicated in various stages of inflammatory conditions with the production of a variety of potent oxidants. To investigate the extent of the involvement of MPO in aging, we measured MPO activities in kidney of rats at different ages maintained with an ad libitum (AL) or a calorie restriction (CR) dietary regimen. Results showed that the MPO activities increased during aging in AL rats, but were significantly attenuated by CR. This result was consistent with altered protein level of MPO during aging. In addition, we were able to detect dityrosine that is a stable end MPO-oxidation product. The amount of dityrosine increased in old AL, but not in old CR rats. To examine the source responsible for increased MPO activity during aging for leukocyte recruitment and infiltration, the levels of vascular cell adhesion molecule (VCAM-1) protein were measured. The level of VCAM-1 showed age-dependent increase in AL rats, which was correlated with higher activity of MPO in old AL rats. Furthermore, we have found that LPS-induced inflammation increased the activity and protein levels of MPO, and VCAM-1 expression in young rat kidneys. These findings suggest that increased MPO activity with aging may related to increased recruitment of inflammatory cells, contributing to protein oxidation accumulation in the aging process. We propose that age-related alterations of MPO, dityrosine, and VCAM were modulated by CR through its anti-inflammatory action.  相似文献   
120.
Li X  Ji C  Gu J  Xu J  Jin Z  Sun L  Zou X  Lin Y  Sun R  Wang P  Gu S  Mao Y 《Molecular biology reports》2005,32(2):127-131
Triple-A syndrome (MIM 231550; also known as Allgrove syndrome) is an autosomal recessive disorder characterized by adrenocorticotropin hormone (ACTH)-resistant adrenal insufficiency, achalasia of the oesophageal cardia and alacrima. Much initial molecular analysis supported that Triple-A syndrome was caused by mutations in AAAS, a WD-repeat protein gene. Here we report cloning and characterization of a novel splice variant of human AAAS, which we named AAAS-v2, which is located on the human chromosome 12p13. The cDNA is 1703bp, encoding a 513-amino acid polypeptide, which contains three WD40 domains, one less than the original which we called AAAS-v1 (Gen Bank: NM_015665.3). RT-PCR analysis in our work revealed that AAAS-v2 and AAAS-v1 were ubiquitously detected in human multiple tissue cDNA (MTC) panels (CLONTECH).The nucleotide sequence reported in this paper has been submitted to GenBank under accession number AY237818.Xin Li: These two authors contributed equally to this paper.Chaoneng Ji: These two authors contributed equally to this paper.  相似文献   
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