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141.
Le Wang Xiaodong She Guixia Lv Yongnian Shen Qing Cai Rong Zeng Caixia Li Yiping Ge Shuwen Deng G. S. de Hoog Min Li Weida Liu 《Mycopathologia》2013,175(3-4):331-338
We report a case of mucocutaneous phaeohyphomycosis caused by Exophiala spinifera. Crusty plaques and nodules were major clinical features. Histological examination revealed brown yeast-like cells and hyphae. Mycological and molecular data identified E. spinifera as etiologic agent. Oral itraconazole was effective, which was in accordance with the results of in vitro susceptibility testing. We speculated that her pregnancy may play a role of risk factor in the infection by E. spinifera. 相似文献
142.
Shutian Tao Shaoling Zhang Rong Tsao Marie Thérèse Charles Raymond Yang 《Archives Of Phytopathology And Plant Protection》2013,46(16):1564-1578
Six selected antioxidants (catechin, quercetin-3-galactoside, cyanidin-3-glucoside, pelargonidin-3-glucoside, ellagic and gallic acids) were evaluated in vitro for their antifungal activities and mode of action on Botrytis cinerea Pers., one of the most important pathogens of strawberries. Inhibitory effects were found for all the tested antioxidants, but varied at different fungal developmental stages. Catechin and quercetin-3-galactoside showed linear inhibitory effects on germ tube elongation, with the highest suppression ratios of 54.8% and 58.8% respectively. No significant effect was found on spore germination between treatments and control. Gallic acid showed very strong and linear inhibition on spore germination (r = ?0.95), but the effect diminished after spore germination. Cyanidin-3-glucoside and pelargonidin-3-glucoside provided effective control on the fungi as concentrations increased. The arresting effect of ellagic acid on development of B. cinerea was quadratic. Ellagic acid inhibited germ tube elongation and mycelial growth at its highest and lowest concentrations, while no effects were observed at its medium concentration used in this study. 相似文献
143.
Yujing Huang Ying Qi Yanping Ma Rong He Yaohua Ji Zhengrong Sun Qiang Ruan 《Journal of biosciences》2013,38(3):479-485
MicroRNAs (miRNAs) are small RNAs, 19–23 nucleotides in length, which regulate a variety of cellular processes. Human cytomegalovirus (HCMV) encodes only one intronic miRNA: human cytomegalovirus microRNA UL36 (hcmv-miR-UL36). In this study, we found that over-expression of hcmv-miR-UL36 resulted in a more than threefold increase in HCMV DNA synthesis at 24 h post infection. Fifteen putative targets of hcmv-miR-UL36 were identified using hybrid PCR, one being the HCMV UL138 gene that has previously been identified as a novel latency-associated determinant of HCMV infection. Down-regulation of UL138 expression by hcmv-miR-UL36 was validated using luciferase reporter assays and Western blot analysis in HEK293 cells. In the presence of hcmv-miR-UL36, we observed a 74.6% decrease in luciferase activity and a 46.2% decrease in HCMV UL138 protein expression. Our results indicate that hcmv-miR-UL36 may be a viral miRNA contributing to HCMV replication. 相似文献
144.
The association between CD14 gene C-260T polymorphism and coronary heart disease risk: a meta-analysis 总被引:1,自引:0,他引:1
Hong Pu Jiong Yin Yan Wu Dongming Zhang Yanian Wang Rong Zhou Lijuan Jiang Yan Liu 《Molecular biology reports》2013,40(6):4001-4008
Monocyte differentiation antigen CD14 is considered an important cell-activating mediator of inflammatory responses that may result in atherosclerosis, coronary heart disease (CHD), thrombus formation, and myocardial infarction (MI). A common C-260T polymorphism in the promoter of the CD14 gene, the trans-membrane receptor of lipopolysaccharides, has been inconsistently associated with CHD. To investigate this inconsistency, we performed a meta-analysis of 28 studies involving a total of 13,335 CHD cases and 7,979 controls for C-260T of the CD14 gene to evaluate the effect of CD14 on genetic susceptibility for CHD. An overall random effects odds ratio of 1.24 (95 % CI: 1.12–1.36, P < 10?5) was found for T allele. Significant results were also observed using dominant (OR = 1.34, 95 % CI: 1.17–1.54, P < 10?4) or recessive genetic model (OR = 1.25, 95 % CI: 1.10–1.41, P = 0.0004). There was strong evidence of heterogeneity (P < 10?5), which largely disappeared after stratification by ethnicity. After stratified by ethnicity, significant results were found in East Asians; whereas no significant associations were found among Caucasians and other ethnic populations in all genetic models. In the stratified analysis according to sample size, CHD endpoints, and HWE status, significantly increased risks for the polymorphism were found in all genetic models. In conclusion, our results indicate that the CD14 C-260T polymorphism is a risk factor of CHD, especially in East Asians. However, additional very large-scale studies are warranted to confirm our results. 相似文献
145.
Twelve groups of fossils, including graptolites, brachiopods, nautiloids, trilobites, corals, crinoids, bryozoans, conodonts, ostracods, gastropods, chitinozoans, and acritarchs expired in different but substantial magnitude and global extent during the late Caradoc to latest Ashgill. It indicates a multiple‐episodic mass extinction containing the possible Prologue (late Caradoc), Climax episode (Rawtheyan) and Epilogue (late Hirnantian). The main causes of this mass extinction are recognized as a global sea‐level lowering in the climax and remarkable rapid rise at the final, and global cooling. The Chinese data, especially from the South China Paleoplate, are evaluated first. They are significant for explaining this global bioevent. 相似文献
146.
Rong Huang Daifang Wang Shuzhen Liu Longhua Guo Fangfang Wang Zhenyu Lin Bin Qiu Guonan Chen 《Chirality》2013,25(11):751-756
The preparative‐scale separation of chiral compounds is vitally important for the pharmaceutical industry and related fields. Herein we report a simple approach for rapid preparative separation of enantiomers using functional nucleic acids modified gold nanoparticles (AuNPs). The separation of DL‐tryptophan (DL‐Trp) is demonstrated as an example to show the feasibility of the approach. AuNPs modified with enantioselective aptamers were added into a racemic mixture of DL‐Trp. The aptamer‐specific enantiomer (L‐Trp) binds to the AuNPs surface through aptamer‐L‐Trp interaction. The separation of DL‐Trp is then simply accomplished by centrifugation: the precipitate containing L‐Trp bounded AuNPs is separated from the solution, while the D‐Trp remains in the supernatant. The precipitate is then redispersed in water. The aptamer is denatured under 95 °C and a second centrifugation is then performed, resulting in the separation of AuNPs and L‐Trp. The supernatant is finally collected to obtain pure L‐Trp in water. The results show that the racemic mixture of DL‐Trp is completely separated into D‐Trp and L‐Trp, respectively, after 5 rounds of repeated addition of fresh aptamer‐modified AuNPs to the DL‐Trp mixture solution. Additionally, the aptamer‐modified AuNPs can be repeatedly used for at least eight times without significant loss of its binding ability because the aptamer can be easily denatured and renatured in relatively mild conditions. The proposed approach could be scaled up and extended to the separation of other enantiomers by the adoption of other enantioselective aptamers. Chirality 25:751–756, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
147.
Jay S. Berger James A. Ernst Angelo C. Nicoletta Leslie A. Hull Jianxin Yang Rong Qiu 《Journal of biomolecular structure & dynamics》2013,31(3):285-291
Abstract Whether or not surface salt bridges have a strong stabilizing effect on the native structure in proteins remains uncertain. Previous studies of model peptides have shown that salt bridges spaced at i,i+4 along the chain are more stabilizing than those spaced at i,i+3, with a preference for the order acid-base rather than base-acid from N to C terminus. An analysis of the effect of spacing the ion pairs in short helical peptides is presented, in which acidic and basic side chains spaced two or three residues apart alternate along the chain. The mixed spacing proves to be stabilizing relative to pure spacings. A control peptide in which salt bridges were spaced uniformly three residues apart proved to form a β-sheet structure rather than a-helix. This is due to formation of a silk-like apolar face consisting of alanine side chains; the mesoscopic structure formed by these sheets can be imaged by scanning microscopy. 相似文献
148.
Hydrocotyle peltiformis R.Li & H.Li,sp.nov.
盾叶天胡荽 (S1-2.Fig.1,S1-3.Fig.2)
Type:China.Yunnan:Baoshan Prefecture,Longyang,Mangkuang township,Baihualing village,spring pool,east side of Gaoligong Shan,second evergreen broad-leaved forest,growing along trail,25°18′20.9″(N,98°47′59.7″ E,alt.1600 m,2007-10-12,H.Li R.Li & X.C.Shi 1337 (holotype,KUN). 相似文献
149.
Qian Lu Chong Wang Rong Pan Xinghua Gao Zhifeng Wei Yufeng Xia Yue Dai 《Journal of cellular biochemistry》2013,114(5):1009-1019
Histamine, a major mediator present in mast cells that is released into the extracellular milieu upon degranulation, is well known to possess a wide range of biological activities in several classic physiological and pathological processes. However, whether and how it participates in angiogenesis remains obscure. In the present study, we observed its direct and synergistic action with basic fibroblast growth factor (bFGF), an important inducer of angiogenesis, on in vitro angiogenesis models of endothelial cells. Data showed that histamine (0.1, 1, 10 µM) itself was absent of direct effects on the processes of angiogenesis, including the proliferation, migration, and tube formation of endothelial cells. Nevertheless, it could concentration‐dependently enhance bFGF‐induced angiogenesis as well as production of vascular endothelial growth factor (VEGF) from endothelial cells. The synergistic effect of histamine on VEGF production could be reversed by pretreatments with diphenhydramine (H1‐receptor antagonist), SB203580 (selective p38 mitogen‐activated protein kinase (MAPK) inhibitor) and L ‐NAME (nitric oxide synthase (NOS) inhibitor), but not with cimetidine (H2‐receptor antagonist) and indomethacin (cyclooxygenase (COX) inhibitor). Moreover, histamine could augment bFGF‐incuced phosphorylation and degradation of IκBα, a key factor accounting for the activation and translocation of nuclear factor κB (NF‐κB) in endothelial cells. These findings indicated that histamine was able to synergistically augment bFGF‐induced angiogenesis, and this action was linked to VEGF production through H1‐receptor and the activation of endothelial nitric oxide synthase (eNOS), p38 MAPK, and IκBα in endothelial cells. J. Cell. Biochem. 114: 1009–1019, 2013. © 2012 Wiley Periodicals, Inc. 相似文献