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941.
Ahmed A. ElSharawy Guoyi Yang Xiaoping Hu 《Archives Of Phytopathology And Plant Protection》2013,46(8):646-663
Verticillium dahliae is one of the most important pathogens causing Verticillium wilt. We studied the characterisation of the genetic relationship between virulence, vegetative compatibility groups (VCGs) and inter-simple sequence repeat (ISSR). A total of 48 V. dahliae isolates, in which 16 are collected from different cotton growing regions in China and 4 isolates belonged to all known VCGs, are used. Half of them were found highly virulent. Mutants (565) were obtained using the nitrate non-utilising mutant. These mutants were grouped into three VCGs: VCG1 (27 isolates), VCG 2 (14 isolates) and VCG 3 (7 isolates). Use of ISSR indicated two main clusters that were related to VCG and virulence. Genetic diversity lineages were obviously correlated to VCGs and ISSRs according to their geographical origin, virulence and ISSR genetic variation. This study could be useful to design and develop effective management strategies beside for quarantine purposes on Verticillium wilt control. 相似文献
942.
943.
Wu Song Chun-Fu Wu Ping Liu Rong-Wu Xiang Fang Wang Ying-Xu Dong Jing-Yu Yang 《Neurochemical research》2013,38(1):153-161
Uridine, a pyrimidine nucleoside, has been proposed to be a potential signaling molecule in the central nervous system. The understanding of uridine release in the brain is therefore of fundamental importance. The present study was performed to determine the characteristics of basal and morphine-induced uridine release in the striatum of freely moving mice by using the microdialysis technique. To ascertain whether extracellular uridine was derived from neuronal release, the following criteria were applied: sensitivity to (a) K+ depolarization, (b) Na+ channel blockade and (c) removal of extracellular Ca2+. Uridine levels were not greatly affected by infusion of tetrodotoxin (TTX) and were unaffected by either Ca2+-free medium or in the presence of EGTA (a calcium chelator), suggesting that basal extracellular uridine levels were maintained mainly by non-vesicular release mechanisms. In addition, both systemic and local application of morphine increased striatal uridine release. The morphine-induced release was reversed by naloxone pretreatment, but was unaffected by TTX or EGTA infusion. Moreover, co-administration of morphine and nitrobenzylthioinosine (NBTI, an inhibitor of nucleotide transporter) produced increases of uridine levels similar to that produced by NBTI or morphine alone, suggesting a nucleotide transporter mechanism involved. Taken together, these findings suggest that morphine produces a μ-opioid receptor-mediated uridine release via nucleoside transporters in a TTX- and calcium-independent manner. 相似文献
944.
Genetic heterogeneity could reduce the power of linkage analysis to detect risk loci for complex traits such as alcohol dependence (AD). Previously, we performed a genomewide linkage analysis for AD in African-Americans (AAs) (Biol Psychiatry 65:111–115, 2009). The power of that linkage analysis could have been reduced by the presence of genetic heterogeneity owing to differences in admixture among AA families. We hypothesized that by examining a study sample whose genetic ancestry was more homogeneous, we could increase the power to detect linkage. To test this hypothesis, we performed ordered subset linkage analysis in 384 AA families using admixture proportion as a covariate to identify a more homogeneous subset of families and determine whether there is increased evidence for linkage with AD. Statistically significant increases in lod scores in subsets relative to the overall sample were identified on chromosomes 4 (P = 0.0001), 12 (P = 0.021), 15 (P = 0.026) and 22 (P = 0.0069). In a subset of 44 families with African ancestry proportions ranging from 0.858 to 0.996, we observed a genomewide significant linkage at 180 cM on chromosome 4 (lod = 4.24, pointwise P < 0.00001, empirical genomewide P = 0.008). A promising candidate gene located there, GLRA3, which encodes a subunit of the glycine neurotransmitter receptor. Our results demonstrate that admixture proportion can be used as a covariate to reduce genetic heterogeneity and enhance the detection of linkage for AD in an admixed population such as AAs. This approach could be applied to any linkage analysis for complex traits conducted in an admixed population. 相似文献
945.
Yi Hong Juan Yang Xin Shen Huifen Zhu Xiaoxu Sun Xue Wen Jing Bian Heyu Hu Lu Yuan Juan Tao Ping Lei Guanxin Shen 《Cancer immunology, immunotherapy : CII》2013,62(3):447-454
Transferrin receptor (TfR) has been used as a target for the antibody-based therapy of cancer due to its higher expression in tumors relative to normal tissues. Great potential has been shown by anti-TfR antibodies combined with chemotherapeutic drugs as a possible cancer therapeutic strategy. In our study, we investigated the anti-tumor effects of anti-TfR monoclonal antibody (mAb) alone or in combination with sinomenine hydrochloride in vitro. Results suggested that anti-TfR mAb or sinomenine hydrochloride could induce apoptosis, inhibit proliferation, and affect the cell cycle. A synergistic effect was found in relation to tumor growth inhibition and the induction of apoptosis when anti-TfR mAb and sinomenine hydrochloride were used simultaneously. The expression of COX-2 and VEGF protein in HepG2 cells treated with anti-TfR mAb alone was increased in line with increasing dosage of the agent. In contrast, COX-2 expression was dramatically decreased in HepG2 cells treated with sinomenine hydrochloride alone. Furthermore, we demonstrated that the inhibitory effects of sinomenine hydrochloride and anti-TfR mAb administered in combination were more prominent than when the agents were administered singly. To sum up, these results showed that the combined use of sinomenine hydrochloride and anti-TfR mAb may exert synergistic inhibitory effects on human hepatoma HepG2 cells in a COX-2-dependent manner. This finding provides new insight into how tumor cells overcome the interference of iron intake to survive and forms the basis of a new therapeutic strategy involving the development of anti-TfR mAb combined with sinomenine hydrochloride for liver cancer. 相似文献
946.
A targeted approach for direct topical antimicrobial delivery involving the formulation of impregnated freeze-dried wafers prepared from a natural polymer has been assessed to consider potential for treatment of wounded skin. The synthetic cationic antimicrobial peptides (CAPs) NP101 and NP108 were found to have modest in vitro activity against bacterial species commonly associated with wound infections. Minimum inhibitory concentration/minimum bactericidal concentrations against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa were found to be 0.31 mg/ml for NP101 and 0.25–0.5 mg/ml for NP108. Rapid, substantial cytoplasmic potassium loss was induced by NP108 in E. coli, but not the other species. Through scanning electron microscopy, both CAPs were observed to alter cell morphology, prevent normal septation, promote cell aggregation and trigger release or formation of extracellular filaments. Wafers harbouring these agents displayed substantial antibacterial activity when assessed by standard diffusion assay. These data confirm that topical delivery of CAPs, through their incorporation within freeze-dried wafer formulations prepared from natural polymers, represents a potential viable approach for treating skin infection. 相似文献
947.
948.
Chuanyan Yang Lingling Wang Qiufen Jiang Jingjing Wang Feng Yue Huan Zhang Zhibin Sun Linsheng Song 《Gene》2013
Metallothioneins (MTs), a superfamily of cysteine-rich proteins, perform multiple functions, such as maintaining homeostasis of essential metals, detoxification of toxic metals and scavenging of oxyradicals. In this study, the promoter region of a metallothionein (MT) gene from Bay scallop Argopecten irradians (designed as AiMT1) was cloned by the technique of genomic DNA walking, and the polymorphisms in this region were screened to find their association with susceptibility or tolerance to high temperature stress. One insert–deletion (ins–del) polymorphism and sixteen single nucleotide polymorphisms (SNPs) were identified in the amplified promoter region. Two SNPs, − 375 T–C and − 337 A–C, were selected to analyze their distribution in the two Bay scallop populations collected from southern and northern China coast, which were identified as heat resistant and heat susceptible stocks, respectively. There were three genotypes, T/T, T/C and C/C, at locus − 375, and their frequencies were 25%, 61.1% and 13.9% in the heat susceptible stock, while 34.2%, 42.1% and 23.7% in the resistant stock, respectively. There was no significant difference in the frequency distribution of different genotypes between the two stocks (P > 0.05). In contrast, at locus − 337, three genotypes A/A, A/C and C/C were revealed with the frequencies of 11.6%, 34.9% and 53.5% in the heat susceptible stock, while 45.7%, 32.6% and 21.7% in the heat resistant stock, respectively. The frequency of C/C genotype in the heat susceptible stock was significantly higher (P < 0.01) than that in the heat resistant stock, while the frequency of A/A in the heat resistant stock was significantly higher (P < 0.01) than that in the heat susceptible stock. Furthermore, the expression of AiMT1 mRNA in scallops with C/C genotype was significantly higher than that with A/A genotype (P < 0.05) after an acute heat treatment at 28 °C for 120 min. These results implied that the polymorphism at locus − 337 of AiMT1 was associated with the susceptibility/tolerance of scallops to heat stress, and the − 337 A/A genotype could be a potential marker available in future selection of Bay scallop with heat tolerance. 相似文献
949.
Yi Huang Jianqing Zhou Huadan Ye Limin Xu Yanping Le Xi Yang Weifeng Xu Xiaoyan Huang Jiangfang Lian Shiwei Duan 《Gene》2013
The goal of our study is to evaluate the contribution of CXCL12 rs1746048 (hg19, chr10:44775574) to the risk of CHD in Han Chinese, and to summarize its role in CHD through meta-analysis of existing studies among various ethnic groups. Significant association is observed between rs1746048-C and an increased risk of CHD in Han Chinese (χ2 = 5.41, df = 1, P = 0.02). Post hoc analysis reveals an even stronger association of rs1746048 with the risk of CHD for subjects aged 65 years or older (genotype: χ2 = 8.39, df = 2, P = 0.015; allele: χ2 = 9.13, df = 1, P = 0.003, odd ratio (OR) = 1.91, 95% confidential interval (CI) = 1.25–2.91). A break down analysis by gender shows that rs1746048 is likely a CHD risk factor under the recessive model in males (CC + CT versus TT: P = 0.05, χ2 = 3.59, df = 1, OR = 1.72, 95% CI = 1.00–3.04). In addition, a meta-analysis of ten studies among over 107,000 individuals confirms that rs1746048 is a risk factor of CHD (P < 0.0001, OR = 1.12, 95% CI = 1.09–1.15) and this agrees with the findings of our case–control study in Han Chinese. 相似文献
950.
包括过氧化氢(Hzoz)在内的活性氧通过引起细胞内钙的变化而造成细胞损伤。然而,不同浓度的H202可以导致细胞内不同的钙变化,并激活不同的信号通路。细胞内钙振荡是其中的一种钙信号变化形式,钙振荡可以调控转录因子NF—KB的活性。该研究探讨可以诱导支气管上皮细胞内钙振苏发生的H2o2浓度。体外培养人支气管上皮细胞,采取钙离子荧光探针Fura_2标记细胞。并使用离子成像系统,观测不同浓度的H:0:(0~1000μmol/L)作用下细胞内钙浓度的变化。结果发现,低于50μmol/L的H202仅仅引起“钙火花”;50~500μmol/L的H202导致细胞内钙振荡的发生;而1000μmol/L的H202引起细胞内持续的高钙;同时也证实150μmol/L的H202诱发明显的钙振荡,而钙振荡随后引起了NF—KB活性的升高。该研究提示,适当浓度的H:0:可以诱发支气管上皮细胞内钙振荡的发生,推测可能是活性氧导致慢性气道炎症损伤的一个机制。 相似文献