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961.

Background

We present the first comprehensive analysis of Mycobacterium tuberculosis (MTB) isolates circulating in southern Taiwan. In this 9-year population-based study, the TB situation in the Kaohsiung region was characterized by genotypic analysis of 421 MTB isolates.

Methods

All 421 isolates of MTB were analyzed by spoligotyping and MIRU-VNTR typing. Drug-resistance patterns were also analyzed.

Results

The percentage of EAI (East African-Indian) strains increased across sampling years (2000–2008) in southern Taiwan, whereas the proportion of Beijing lineages remained unchanged. Clustering was more frequent with EAI genotype infections (odds ratio = 3.6, p<0.0001) when compared to Beijing genotypes. Notably, MTB resistance to streptomycin (STR) had significantly increased over time, but resistance to other antibiotics, including multidrug resistance, had not. Three major genes (gidB, rpsL and rrs) implicated in STR resistance were sequenced and specific mutations identified.

Conclusions

This study revealed that EAI strains were highly transmissible and that STR resistance has increased between 2000 and 2008 in Kaohsiung, Taiwan.  相似文献   
962.
研究不同pH值下,口服靶向FOXO1与GDF-8基因反义RNA寡核苷酸药物对药效的影响.化学合成靶向FOXO1与GDF-8基因的有效反义RNA寡核苷酸片段,调节药物PH值,通过灌胃方式给药,给药20 d后处死小鼠,进行体重,腿部肌肉增长情况分析.提取腿部肌肉组织总RNA,用real time PCR检测FOXO1与GDF-8基因的表达.结果表明,服用RNA oligos的试验组小鼠腿部肌肉重量均比对照组肌肉重量增长快.其中pH为7.0的RNA oligos的效果比pH为5.0的效果好, pH9.0的RNA oligos的作用效果最弱.与小鼠体重变化结果一致,real time PCR检测实验组FOXO1与GDF-8基因转录水平较对照组均有明显下降,其中服用pH为7.0的RNA oligos的下降最多.因此,口服靶向FOXO1与GDF-8基因的反义RNA寡核苷酸药物的最适pH值应为中性偏酸.  相似文献   
963.
TRAF2 is an adaptor protein that regulates the activation of the c-Jun N-terminal kinase (JNK) and IkappaB kinase (IKK) signaling cascades in response to tumor necrosis factor alpha (TNF-alpha) stimulation. Although the downstream events in TNF-alpha signaling are better understood, the membrane-proximal events are still elusive. Here, we demonstrate that TNF-alpha and cellular stresses induce TRAF2 phosphorylation at serine 11 and that this phosphorylation is required for the expression of a subset of NF-kappaB target genes. Although TRAF2 phosphorylation had a minimal effect on the TNF-alpha-induced rapid and transient IKK activation, it was essential for secondary and prolonged IKK activation. Consistent with this, TRAF2 phosphorylation is not required for its recruitment to the TNFR1 complex in response to TNF-alpha stimulation but is required for its association with a cytoplasmic complex containing RIP1 and IKK. In addition, TRAF2 phosphorylation was essential for the full TNF-alpha-induced activation of JNK. Notably, TRAF2 phosphorylation increased both basal and inducible c-Jun and NF-kappaB activities and rendered cells resistant to stress-induced apoptosis. Moreover, TRAF2 was found to be constitutively phosphorylated in some lymphomas. These results unveil a new, finely tuned mechanism for TNF-alpha-induced IKK activation modulated by TRAF2 phosphorylation and suggest that TRAF2 phosphorylation contributes to elevated levels of basal NF-kappaB activity in certain human cancers.  相似文献   
964.
Aquatic plants develop strong fragment propagation and colonization ability to endure the natural disturbances. However, detailed research of ability to endure the natural disturbances has been lacking to date. Therefore, reproduction (shoot) and colonization (root) of shoot fragments of Potamogeton crispus L. with or without apices were investigated for the effect of apical dominance, and the growth of decapitated shoot fragments at three lengths (2, 4, 6 cm) was compared. Meanwhile, fragment propagation at levels of bud position was studied for bud position effect after escaping from apical dominance. The results showed significant increases occurred in the outgrowth of lateral branches on fragments decapitated compared with the fragments with apices, implying that apical dominance exists. Different lengths of fragments showed little difference in biomass allocations, but significant differences were noted in their propagation. Meanwhile, the effect of bud position was verified, due to the significant difference of average reproduction per node among the three length groups. Thus, the present study has made progress in the current understanding of aquatic plant dispersion among natural systems and contributes to improve methods of in vitro propagation for re-implantation purposes.  相似文献   
965.
By using a modified biotin–streptavidin capture method, a total of 12 microsatellite loci were developed and characterized for Michelia coriacea (Magnoliaceae), a critically endangered endemic to Southeast Yunnan, China. The number of alleles (A) ranged from two to six in 30 samples of this species. The ranges of observed (H O ) and expected (H E ) heterozygosities were 0.033–0.8000 and 0.033–0.7910, respectively. Cross-species amplification in M. yunnanensis showed that a subset of these markers holds promise for congeneric species. These polymorphic SSR markers would be useful tools for population genetics studies on M. coriacea and other congeneric species.  相似文献   
966.
We sought to identify cells and cytokines in bronchoalveolar lavage (BAL) fluids that distinguish asthma from healthy control subjects and those that distinguish controlled asthma from uncontrolled asthma. Following informed consent, 36 human subjects were recruited for this study. These included 11 healthy control subjects, 15 subjects with controlled asthma with FEV1≥80% predicted and 10 subjects with uncontrolled asthma with FEV1 <80% predicted. BAL fluid was obtained from all subjects. The numbers of different cell types and the levels of 48 cytokines were measured in these fluids. Compared to healthy control subjects, patients with asthma had significantly more percentages of eosinophils and neutrophils, IL-1RA, IL-1α, IL-1β, IL-2Rα, IL-5, IL-6, IL-7, IL-8, G-CSF, GROα (CXCL1), MIP-1β (CCL4), MIG (CXCL9), RANTES (CCL5) and TRAIL in their BAL fluids. The only inflammatory markers that distinguished controlled asthma from uncontrolled asthma were neutrophil percentage and IL-8 levels, and both were inversely correlated with FEV1. We examined whether grouping asthma subjects on the basis of BAL eosinophil % or neutrophil % could identify specific cytokine profiles. The only differences between neutrophil-normal asthma (neutrophil≤2.4%) and neutrophil-high asthma (neutrophils%>2.4%) were a higher BAL fluid IL-8 levels, and a lower FEV1 in the latter group. By contrast, compared to eosinophil-normal asthma (eosinophils≤0.3%), eosinophil-high asthma (eosinophils>0.3%) had higher levels of IL-5, IL-13, IL-16, and PDGF-bb, but same neutrophil percentage, IL-8, and FEV1. Our results identify neutrophils and IL-8 are the only inflammatory components in BAL fluids that distinguish controlled asthma from uncontrolled asthma, and both correlate inversely with FEV1.  相似文献   
967.
This study was designed to evaluate significant associations between single nucleotide polymorphisms (SNPs) and milk composition and milk production traits in Chinese Holstein cows. Six SNPs were identified in the κ-casein gene using pooled DNA sequencing. The identified SNPs were genotyped by Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) methods from 507 individuals. Out of six, we identified three non-synonymous SNPs (g.10888T>C, g.10924C>A and g.10944A>G) that changed in the protein product. SIFT (Sorting_Intolerant_From_Tolerant) prediction score (0.01) demonstrated that protein changed Isoleucine > Threonine (g.10888T>C) will affect the phenotypes. Significant associations between identified SNPs and three yield traits (milk, protein and fat) and two composition traits (fat and protein percentages) were found whereas it did not reach significance for fat percentage in haplotypes association. Importantly, the significant SNPs in our results showed a large proportion of the phenotypic variation of milk protein yield and concentration. Our results suggest that CSN3 is an important candidate gene that influences milk production traits, and identified polymorphisms and haplotypes could be used as a genetic marker in programs of marker-assisted selection for the genetic improvement of milk production traits in dairy cattle.  相似文献   
968.
杨顺  孙微  刘杏忠  向梅春 《生物多样性》2016,24(9):1068-125
石生真菌是一类生长在裸露岩石上形成紧凑暗色菌落的特殊生命, 在自然界未发现其有性生殖结构, 它们具有丰富的物种多样性。石生真菌是地球上最具耐受力的一种真核生命, 具有独特的适应性, 并进化出各种适应机制以占据严酷的生态位, 它们在细胞结构、代谢方式、抗逆机制等方面具有特殊性。尽管石生真菌很常见,但由于其体积小、生长缓慢并且缺乏明显的形态特征而常常被人们忽视。本文在介绍石生真菌的多样性、研究方法和研究历史的基础上, 重点介绍石生真菌的逆境耐受性和抗逆机制以及石生真菌的应用研究。以期能引起科学工作者对这类特殊生境里的真菌研究的重视, 更好地理解这类真菌在地球上的重要作用。  相似文献   
969.
970.

Background

We aimed to compare the long-term survival outcomes and acute toxicity of cisplatin administered weekly versus every three weeks concurrently with intensity-modulated radiotherapy (IMRT) in patients with nasopharyngeal carcinoma (NPC).

Methods

This was a retrospective review of 154 patients with histologically proven, non-disseminated NPC who were treated using IMRT between January 2003 and December 2007. Seventy-three patients (47.4%) received 5–7 weeks of 30–40 mg/m2 cisplatin weekly; 81 patients (52.6%) received two or three cycles of 80 mg/m2 cisplatin every three weeks. IMRT was delivered at 68 Gy/30 fractions to the nasopharyngeal gross target volume and 60–66 Gy to the involved neck area.

Results

The clinical characteristics and treatment factors of the two groups were well-balanced. The median follow-up was 74 months (range, 6–123 months), and the 5-year overall survival, disease-free survival, locoregional relapse-free survival, and distant metastasis–free survival rates were 85.2% vs. 78.9% (P = 0.318), 71.6% vs. 71.0% (P = 0.847), 93.5% vs. 92.6% (P = 0.904), and 80.9% vs. 80.1% (P = 0.925) for the group treated every three weeks and weekly, respectively. Subgroup analyses indicated no significant differences in the survival rates of the two groups among patients with early- or advanced-stage disease. The incidence of acute toxicities was similar between groups.

Conclusion

IMRT with concurrent cisplatin administered weekly or every three weeks leads to similar long-term survival outcomes and acute toxicity in NPC regardless of whether patients have early- or advanced-stage disease.  相似文献   
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