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81.
Lei Cai Shao-Li Deng Li Liang Hui Pan Jia Zhou Mei-Yan Wang Jun Yue Chun-Ling Wan Guang He Lin He 《Human genetics》2013,132(3):265-273
Genetic factors play important roles in the development of tuberculosis (TB). SP110 is a promising candidate target for controlling TB infections. However, several studies associating SP110 single nucleotide polymorphisms (SNPs) with TB have yielded conflicting results. This may be partly resolved by studying other genes associated with SP110, such as MYBBP1A and RELA. Here, we genotyped 6 SP110 SNPs, 8 MYBBP1A SNPs and 5 RELA SNPs in 702 Chinese pulmonary TB patients and 425 healthy subjects using MassARRAY and SNaPshot methods. Using SNP-based analysis with Bonferroni correction, rs3809849 in MYBBP1A [Pcorrected (cor) = 0.0038] and rs9061 in SP110 (Pcor = 0.019) were found to be significantly associated with TB. Furthermore, meta-analysis of rs9061 in East Asian populations showed that the rs9061 T allele conferred significant risk for TB [P = 0.002, pooled odds ratio (OR), 1.24, 95 % confidence interval (CI) = 1.08–1.43]. The MYBBP1A GTCTTGGG haplotype and haplotypes CGACCG/TGATTG within SP110 were found to be markedly and significantly associated with TB (P = 2.00E?06, 5.00E?6 and 2.59E?4, respectively). Gene-based analysis also demonstrated that SP110 and MYBBP1A were each associated with TB (Pcor = 0.011 and 0.035, respectively). The logistic regression analysis results supported interactions between SP110 and MYBBP1A, indicating that subjects carrying a GC/CC genotype in MYBBP1A and CC genotype in SP110 possessed the high risk of developing TB (P = 1.74E?12). Our study suggests that a combination of SP110 and MYBBP1A gene polymorphisms may serve as a novel marker for identifying the risk of developing TB in the Chinese Han population. 相似文献
82.
83.
Jian-Guo Hu Xing-Jun Wu Yi-Fan Feng Gang-ming Xi Ling-Xiao Deng Zhen-Huan Wang Rui Wang Lin Shen Jian-Sheng Zhou He-Zuo Lü 《Neurochemical research》2013,38(3):601-609
The conditioned medium from B104 neuroblastoma cells (B104CM) induces proliferation of oligodendrocyte progenitor cells (OPCs) in vitro. However, the molecular events that occur during B104CM-induced proliferation of OPCs has not been well clarified. In the present study, using OPCs immunopanned from embryonic day 14 Sprague–Dawley rat spinal cords, we explored the activation of several signaling pathways and the expression of several important immediate early genes (IEGs) and cyclins in OPCs in response to B104CM. We found that B104CM can induce OPC proliferation through the activation of the extracellular signal-regulated kinases 1 and 2 (Erk1/2), but not PI3K or p38 MAPK signaling pathways in vitro. The IEGs involved in B104CM-induced OPC proliferation include c-fos, c-jun and Id2, but not c-myc, fyn, or p21. The cyclins D1, D2 and E are also involved in B104CM-stimulated proliferation of OPCs. The activation of Erk results in subsequent expression of IEGs (such as c-fos, c-jun and Id-2) and cyclins (including cyclin D1, D2 and E), which play key roles in cell cycle initiation and OPC proliferation. Collectively, these results suggest that the phosphorylation of Erk1/2 is an important molecular event during OPC proliferation induced by B104CM. 相似文献
84.
In this communication, the effect of acute treatment with lamotrigine (LTG) was investigated on release of main excitatory amino acids (EAA) such as glutamate (Glu) and aspartate (Asp) in the hippocampus of pentylenetetrazol (PTZ)-induced and PTZ-kindled freely moving rats using micro dialysis. The results show that, levels of Glu and Asp significantly increased in the rat hippocampus during the seizure/interical periods for PTZ-status epilepticus (SE) and PTZ-kindled epileptic (EP) rats. The levels of Glu and Asp increased more in EP rat hippocampus than in SE rat hippocampus. After administration of 20 mg/kg LTG, the levels of Glu and Asp significantly decreased in the SE and EP rat hippocampus. The results indicate that: (a) excitability of the PTZ-kindled epileptogenic model is higher than that of the status epilepticus model; (b) the modulation of LTG on the EAA neurotransmitters certainly plays an important role in antiepileptic efficacy, especially in PTZ-kindled epileptic model where the release of EAA was influenced more markedly by acute application of 20 mg/kg LTG. 相似文献
85.
Xia Chen Aiqing Deng Hongzhi Zhou Jinhua Gu 《Molecular and cellular biochemistry》2013,373(1-2):149-159
In the present investigation, we used directed evolution approach to engineer a lipase from metagenomic origin. A variant S311C, was generated, characterized in detail and compared with wild type. Wild type and variant lipases were overexpressed and purified to homogeneity. The temperature optima of the purified lipases (Variant and wild type) were almost same, and found to be 45 and 50 °C, respectively. The variant protein was highly thermostable (54 times) as compared with the wild type at 60 °C. The variant displayed very high kinetic efficiency over the wild type protein. Analysis of the homology models of wild type and variant lipase showed that the substitution is on the surface of the protein. This substitution, along with hydrophobic residues in near vicinity may be involved in formation of strong hydrophobic channel leading to active site. This study identifies the role of hydrophobic interactions in protein stability along with enhancement of enzyme activity. 相似文献
86.
87.
Q. T. Kong W. Q. Zhou J. Feng H. Sang D. Q. Deng Z. Wang J. Li Q. L. Shi B. Wu W. D. Liu 《Mycopathologia》2013,175(1-2):187-191
A 62-year-old immunocompetent rural woman who represents an isolated cryptococcal skull infection without systematic involvement is described. Diagnosis was based on positive India ink staining, positive histopathologic examination, and positive culture. Species identification was performed by growth on Sabouraud dextrose agar and CHROMagar medium and by sequencing of the intergenic and internal transcribed spacer regions of the rRNA genes. This case describes a rare presentation of Cryptococcus neoformans infection in a human immunodeficiency virus-negative patient. The lesions were significantly improved with treatment of daily oral itraconazole 400 mg. A maintenance therapy with a low-dose itraconazole was prescribed to warrant a clinical and mycological eradication. A two-year follow-up did not show any recurrence of infection. 相似文献
88.
Maozi Liu Linjing Yang Wenli Deng Ming Su Chen Wang Shuu-Bin Lin 《Journal of biomolecular structure & dynamics》2013,31(5):895-903
Abstract Three triplex DNAs containing 5-bromocytosine[BrC] were studied by vibrational spectroscopy and molecular modelling. Firstly, three oligodeoxypyrimidines of 5′-(TC)3- T4-(BrCT)3 [CBrC], 5′-(TBrC)3-T4-(CT)3 pCC] and 5′-(TBC)3-T4-(BrCT)3 [BrCBC] were synthesized and then reacted with an oligodeoxypurine of 5′-(AG)3 at pH=4.5 in phosphate buffer respectively to form three comparative hairpin triplex named CY,YC and YY. The results of FT-Raman and IR revealed that YY is almost in A-like form, CY and YC are combinations of A-like form and B-like form, but A-form dominates in CY while B-form is equivalent as A-form in YC. The result is consistent with the theoretical analysis. 相似文献
89.
Di Fang Xue Liu Ruichang Zhang Wenjing Deng Lixiang Zhou 《Geomicrobiology journal》2013,30(6):473-478
The potential of a hybrid process incorporating sulfur-based bioleaching and sulfide-based precipitation for treatment of metal-contaminated soil was examined in batch-type experiments. The sulfur-based soil bioleaching process with Acidithiobacillus sp. could be initiated at a wide range of initial pH from 4.0 to 6.3. After 15 days, 98% of Zn, 89% of Cu and 79% of Cd was bioleached. The gaseous sulfides recycling from Desulfovibrio sp.-mediated sulfate-reducing reactor via N2 sparging efficiently treated metal-loaded soil leachate. With a sulfide/metal ratio of 3.0, 88% of Zn, 100% of Cu and 95% of Cd were precipitated, resulting in effluent metal concentrations of 3.5 mg Zn2+/L, 0.2 mg Cu2+/L and 0.03 mg Cd2+/L. Supplemental materials are available for this article. Go to the publisher's online edition of Geomicrobiology Journal to view the supplemental file. 相似文献
90.
Rongya Tao Xiwen Xiong Ronald A. DePinho Chu-Xia Deng X. Charlie Dong 《Journal of lipid research》2013,54(10):2745-2753
Cholesterol homeostasis is crucial for cellular function and organismal health. The key regulator for the cholesterol biosynthesis is sterol-regulatory element binding protein (SREBP)-2. The biochemical process and physiological function of SREBP-2 have been well characterized; however, it is not clear how this gene is epigenetically regulated. Here we have identified sirtuin (Sirt)6 as a critical factor for Srebp2 gene regulation. Hepatic deficiency of Sirt6 in mice leads to elevated cholesterol levels. On the mechanistic level, Sirt6 is recruited by forkhead box O (FoxO)3 to the Srebp2 gene promoter where Sirt6 deacetylates histone H3 at lysines 9 and 56, thereby promoting a repressive chromatin state. Remarkably, Sirt6 or FoxO3 overexpression improves hypercholesterolemia in diet-induced or genetically obese mice. In summary, our data suggest an important role of hepatic Sirt6 and FoxO3 in the regulation of cholesterol homeostasis. 相似文献