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941.
Background
Glutathione S-transferase (GST) variants have been considered as risk factors for the pathogenesis of primary open angle glaucoma (POAG). However, the results have been inconsistent. In this study, we performed a meta-analysis to assess the association between GSTM1 and GSTT1 null genotypes and the risk for POAG.Methods
Published literature from PubMed and EMBASE databases was retrieved. All studies evaluating the association between GSTM1/GSTT1 variants and POAG were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed- or random-effects model.Results
14 studies (1711 POAG cases and 1537 controls) were included in the meta-analysis of GSTM1 genotypes and 10 studies (1306 POAG cases and 1114 controls) were included in the meta-analysis of GSTT1 genotypes. The overall result showed that the association between GSTM1 and GSTT1 null genotypes and risk for POAG was not statistically significant (GSTM1: OR = 1.19, 95% CI = 0.82–1.73, p = 0.361; GSTT1: OR = 1.26, 95% CI = 0.77–2.06, p = 0.365). The results by ethnicity showed that the association between the GSTM1 null genotype and risk for POAG is statistically significant in East Asians (OR = 1.41, 95% CI = 1.04–1.90, p = 0.026), but not in Caucasians (OR = 1.13, 95% CI = 0.69–1.84, p = 0.638) and Latin-American (OR = 1.09, 95% CI = 0.62–1.92, p = 0.767). In addition, there was no significant association of GSTT1 null genotype with risk for POAG in either ethnic population.Conclusions
The present meta-analysis suggested that there might be a significant association of GSTM1 null genotype with POAG risk in East Asians. 相似文献942.
Yang Zhou Lu Gao Haifeng Shi Hengchuan Xia Li Gao Chaoqun Lian Liang Chen Qin Yao Keping Chen Xiaoyong Liu 《Genomics》2013,101(4):256-262
To investigate the molecular mechanism of silkworm resistance to BmNPV infection, we constructed a near-isogenic line (BC8) with BmNPV resistance using highly resistant (NB) and highly susceptible parental strains (306). We investigated variations in the gene expression in the midguts of BmNPV-infected BC8 and 306 at 12 h pi using the microarray. 92 differentially expressed genes were identified. Real-time qPCR analysis confirmed that 10 genes were significantly up-regulated or down-regulated in the midguts of BC8 and NB compared to 306. To our knowledge, we first defined the role of the amino acid transporter and 26S proteasome in insect antiviral. However, serine protease was not completely consistent with data of reported previously in insect antiviral. The role of the 5 genes (Bm123, Bm122, COP β′, aquaporin, glycoside hydrolases) was also demonstrated in insect antiviral. Our results provided new insights into the molecular mechanism of the Bombyx mori immune response against BmNPV infection. 相似文献
943.
Luís Roque Noélia Duarte Maria Rosário Bronze Catarina Garcia Julia Alopaeus Jesus Molpeceres 《Biofouling》2013,29(8):880-892
AbstractGlycyrrhiza glabra L. is considered an important source of bioactive compounds. This study aimed at the development of an efficient solution for the treatment of oral candidiasis. Several extracts of Glycyrrhiza glabra L. were prepared using different solvents and their potential in vitro antifungal activity was assessed. Ethanolic extracts showed the most promising results against C. albicans. This extract was incorporated into mucoadhesive nanoparticles (PLA, PLGA and alginate), which were further included in an oral gel, an oral film and a toothpaste, respectively. The results showed that nanoparticles were successfully produced, presenting a mean size among 100–900?nm with high encapsulation efficiency. In vitro studies showed that the most bioadhesive formulation was the oral film with extract-loaded PLGA nanoparticles, followed by the toothpaste with extract-loaded alginate nanoparticles and the oral gel with extract-loaded PLA nanoparticles. 相似文献
944.
The meso-scale structure of symmetric diblock copolymer under cylindrical confinement is studied by dissipative particle dynamics (DPD). The simulation results show that coiled cylindrical geometry is favored in the presence of larger cylinder radius (R/L 0>~1.5), and the number of rings depends on the cylinder radius. Because of the cylinder wall's selectivity, each block can form the central core, but only the preferential block forms the outmost layer. An approximately linear relationship exists between structure transition point, which is approximately in proportion to the 3/5 exponential of chain length of copolymer and number of layers. As the cylinder radius is decreased, a helical morphology is found. Lamellae parallel to the underside of the cylinder appear when the cylinder radius is made smaller (R/L 0 < ~1.1). 相似文献
945.
The mechanism and dynamical properties for the title reaction have been investigated theoretically. Three reaction pathways have been found. Geometries, vibrational frequencies, infra-red (IR) intensities and relative energies for various stationary points in the three reaction channels have been determined respectively. The corresponding rate constants at the B3LYP/6-31++G(2d,2p) level have been deduced over a wide temperature range of 200–2000 K by using canonical variational transition state theory with small curvature tunnelling effect. Solvent effects are taken into account via the Onsager model of self-constant reaction field at the same level of theory. This preliminary study shows that the complex formation is favoured by the use of water solvent. 相似文献
946.
Patrícia Patrício António Mateus-Pinheiro Nuno Sousa Luísa Pinto 《Molecular neurobiology》2013,48(1):84-96
Since adult neurogenesis became a widely accepted phenomenon, much effort has been put in trying to understand the mechanisms involved in its regulation. In addition, the pathophysiology of several neuropsychiatric disorders, such as depression, has been associated with imbalances in adult hippocampal neurogenesis. These imbalances may ultimately reflect alterations at the cell cycle level, as a common mechanism through which intrinsic and extrinsic stimuli interact with the neurogenic niche properties. Thus, the comprehension of these regulatory mechanisms has become of major importance to disclose novel therapeutic targets. In this review, we first present a comprehensive view on the cell cycle components and mechanisms that were identified in the context of the homeostatic adult hippocampal neurogenic niche. Then, we focus on recent work regarding the cell cycle changes and signaling pathways that are responsible for the neurogenesis imbalances observed in neuropathological conditions, with a particular emphasis on depression. 相似文献
947.
Dah-Yuu Lu Bor-Ren Huang Wei-Lan Yeh Hsiao-Yun Lin Shiang-Suo Huang Yu-Shu Liu Yueh-Hsiung Kuo 《Molecular neurobiology》2013,48(3):863-874
Accumulating evidence suggests that inflammatory processes in the central nervous system that are mediated by microglial activation play important roles in several neurodegenerative disorders. Therefore, development of methods for microglial inhibition is considered an important strategy in the search for neuroprotective agents. Caffeic acid phenethyl ester (CAPE) is distributed wildly in nature, but rapid decomposition by esterase leads to its low bioavailability. In this study, we investigated the effects of KS370G, a novel caffeic acid phenylethyl amide, on microglial activation. KS370G significantly inhibited the release of nitric oxide (NO) and the expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Treatment with KS370G also induced heme oxygenase (HO)-1 and suppressors of cytokine signaling (SOCS)-3 expression in the microglia. Furthermore, the anti-inflammatory effects of KS370G were found to be regulated by phosphorylated adenosine monophosphate-activated protein kinase-α (AMPK-α) translocated to the nucleus. Moreover, KS370G showed significant anti-neuroinflammatory effects on microglial activation in vivo and on motor behavior as well. The protective effect of KS370G was weakened by an AMPK inhibitor Compound C. This study focuses on the importance of key molecular determinants of inflammatory homeostasis, AMPK, HO-1, and SOCS-3, and their possible involvement in anti-neuroinflammatory responses. 相似文献
948.
Si‐Yuan Sun Yu‐Qing Wang Li‐Ping Li Lu Wang Su Zeng Hui Zhou Hui‐Di Jiang 《Chirality》2013,25(1):43-47
Tetrahydropalmatine (THP), with one chiral center, is an alkaloid that possesses analgesic and many other pharmacological actives. The aim of the present study is to investigate stereoselective metabolism of THP enantiomers in human liver microsomes (HLM) and elucidate which cytochrome P450 (CYP) isoforms contribute to the stereoselective metabolism in HLM. Additionally, the inhibitions of THP enantiomers on activity of CYP enzymes are also investigated. The results demonstrated that (+)‐THP was preferentially metabolized by HLM. Ketoconazole (inhibitor of CYP3A4/5) inhibited metabolism of (?)‐THP or (+)‐THP at same degree, whereas the inhibition of fluvoxamine (inhibitor of CYP1A2) on metabolism of (+)‐THP was greater than that of (?)‐THP; moreover, the metabolic rate of (+)‐THP was 5.3‐fold of (?)‐THP in recombinant human CYP1A2. Meanwhile, THP enantiomers did not show obvious inhibitory effect on the activity of various CYP isoforms (CYP1A2, 2A6, 2C8, 2C9, 2C19, 2E1, and 3A4/5), whereas (?)‐THP, but not (+)‐THP, significantly inhibited the activity of CYP2D6 with the Ki value of 6.42 ± 0.38 μM. The results suggested that THP enantiomers were predominantly metabolized by CYP3A4/5 and CYP1A2 in HLM, and (+)‐THP was preferentially metabolized by CYP1A2, whereas CYP3A4/5 contributed equally to metabolism of (?)‐THP or (+)‐THP. Besides, the inhibition of CYP2D6 by (?)‐THP may cause drug–drug interaction, which should be considered. Chirality 25:43–47, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
949.
950.