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261.
Microglial-mediated neuroinflammation has been established as playing a vital role in pathogenesis of neurodegenerative disorders. Thus, rational regulation of microglia functions to inhibit inflammation injury may be a logical and promising approach to neurodegenerative disease therapy. The purposes of the present study were to explore the neuroprotective effects and potential molecular mechanism of Schizandrin A (Sch A), a lignin compound isolated from Schisandra chinesnesis. Our observations showed that Sch A could significantly down-regulate the increased production of nitric oxide (NO), tumor necrosis factor (TNF)-α and interleukin (IL)-6 induced by lipopolysaccharide (LPS) both in BV-2 cells and primary microglia cells. Moreover, Sch A exerted obvious neuroprotective effects against inflammatory injury in neurons when exposed to microglia-conditioned medium. Investigations of the mechanism showed the anti-inflammatory effect of Sch A involved the inhibition of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) expression levels and inhibition of the LPS-induced TRAF6-IKKβ-NF-κB pathway. Furthermore, inhibition of Jak2-Stat3 pathway activation and Stat3 nuclear translocation also was observed. In conclusion, SchA can exert anti-inflammatory and neuroprotective effects by alleviating microglia-mediated neuroinflammation injury through inhibiting the TRAF6-IKKβ-NF-κB and Jak2-Stat3 signaling pathways. 相似文献
262.
Mingqiang Zeng Ling Wang Caifang Chen Fanchang Zeng Liang Huang Ruizhi Xue Junjie Chen Benmin Gao Zhengyan Tang 《PloS one》2016,11(2)
Background
Male circumcision (MC) has been shown to reduce the risk of male genital diseases. MC is not commonly practiced among Chinese males and little is known about the factors associated with their knowledge of and willingness for MC. This study was to explore the knowledge regarding the foreskin among Chinese males and to identify factors associated with their willingness to undergo circumcision.Methods
A total of 237 patients with redundant prepuce/phimosis were interviewed through face-to-face interviews. The items on the questionnaire included: demographics, an objective scale assessing knowledge about the foreskin, willingness to have MC, the attitudes of sexual partners and doctors toward redundant prepuce/phimosis, and the approaches that patients used to acquire knowledge regarding the prepuce. Univariate analysis and multiple logistic regression analysis were performed to identify factors that are associated with willingness to be circumcised (WTC).Results
A total of 212 patients completed the interview. Multivariable logistic regression showed that three factors were significantly associated with WTC: being married (OR = 0.43), perceiving redundant prepuce/phimosis as a disease (OR = 1.93), and if a patient’s partner supported MC (OR = 1.39). 58% (n = 122) had received information about the foreskin from another party: 18% (n = 37) from school, 8% (n = 17) from family, 17% (n = 36) from friends, 27% (n = 57) from health care providers. About 4% (n = 8) believed that their partners disliked their redundant prepuce/phimosis. 20% (n = 42) had received doctors’ advice to undergo circumcision.Conclusion
Knowledge about the foreskin was low among Chinese males. Our study elucidates the factors associated with WTC and suggests that more education of the population about the foreskin can help improve the recognition of a correctible abnormality and help patients assess the potential role of MC in their health. 相似文献263.
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Weiliang Qi Yao Tang Wei Zhu Daiyan Li Chengdou Diao Lili Xu Jian Zeng Yi Wang Xing Fan Lina Sha Haiqin Zhang Youliang Zheng Yonghong Zhou Houyang Kang 《Planta》2016,244(2):405-416
Main conclusion
A new wheat-rye 1BL?1RS translocation line, with the characteristics of superior stripe rust resistance and high thousand-kernel weight and grain number per spike, was developed and identified from progenies of wheat-rye- Psathyrostachys huashanica trigeneric hybrids.Abstract
The wheat-rye 1BL?1RS translocation line from Petkus rye has contributed substantially to the world wheat production. However, due to extensive growing of cultivars with disease resistance genes from short arm of rye chromosome 1R and coevolution of pathogen virulence and host resistance, these cultivars successively lost resistance to pathogens. In this study, a new wheat-rye line K13-868, derived from the progenies of wheat-rye-Psathyrostachys huashanica trigeneric hybrids, was identified and analyzed using fluorescence in situ hybridization (FISH), genomic in situ hybridization (GISH), acid polyacrylamide gel electrophoresis (A-PAGE), and molecular markers. Cytological studies indicated that the mean chromosome configuration of K13-868 at meiosis was 2n = 42 = 0.14 I + 18.78 II (ring) + 2.15 II (rod). Sequential FISH and GISH results demonstrated that K13-868 was a compensating wheat-rye 1BL?1RS Robertsonian translocation line. Acid PAGE analysis revealed that clear specific bands of rye 1RS were expressed in K13-868. Simple sequence repeat (SSR) and rye 1RS-specific markers ω-sec-p1/ω-sec-p2 and O-SEC5′-A/O-SEC3′-R suggested that the 1BS arm of wheat had been substituted by the 1RS arm of rye. At the seedling and adult growth stage, compared with its recurrent wheat parent SM51 and six other wheat cultivars containing the 1RS arm in southwestern China, K13-868 showed high levels of resistance to stripe rust (Puccinia striiformis f. sp. tritici, Pst) pathogens prevalent in China, which are virulent to Yr10 and Yr24/Yr26. In addition, K13-868 expresses higher thousand-kernel weight and more grain number per spike than these controls in two growing seasons, suggesting that this line may carry yield-related genes of rye. This translocation line, with significant characteristics of resistance to stripe rust and high thousand-kernel weight and grain number per spike, could be utilized as a valuable germplasm for wheat improvement.266.
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Xiangqian Zhang Xu Zheng Shanwen Ke Haitao Zhu Fang Liu Zemin Zhang Xinxiang Peng Lin Guo Ruizhen Zeng Pei Hou Ziqiang Liu Suowei Wu Meifang Song Jianping Yang Guiquan Zhang 《Plant molecular biology》2016,92(6):701-715
Most environmental perturbations have a direct or indirect deleterious impact on photosynthesis, and, in consequence, the overall energy status of the cell. Despite our increased understanding of convergent energy and stress signals, the connections between photosynthesis, energy and stress signals through putative common nodes are still unclear. Here we identified an endoplasmic reticulum (ER)-localized adenine nucleotide transporter1 (ER-ANT1), whose deficiency causes seedling lethality in air but viable under high CO2, exhibiting the typical photorespiratory phenotype. Metabolic analysis suggested that depletion of ER-ANT1 resulted in circadian rhythm disorders in sucrose synthesis and induced sucrose signaling pathways, indicating that the ER is involved in the regulation of vital energy metabolism in plants. In addition, the defect of ER-ANT1 triggers ER stress and activates the unfolded protein response in plant cells, suggesting ER stress and photorespiration are closely linked. These findings provide an important evidence for a key role of ER-localized ER-ANT1 in convergent energy and stress signals in rice. Our findings support the idea that ATP is a central signal involved in the plant response to a variety of stresses. 相似文献
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270.
Mark C. Vanderwel Hongcheng Zeng John P. Caspersen Georges Kunstler Jeremy W. Lichstein 《Ecology letters》2016,19(4):414-423
Ecologists have limited understanding of how geographic variation in forest biomass arises from differences in growth and mortality at continental to global scales. Using forest inventories from across North America, we partitioned continental‐scale variation in biomass growth and mortality rates of 49 tree species groups into (1) species‐independent spatial effects and (2) inherent differences in demographic performance among species. Spatial factors that were separable from species composition explained 83% and 51% of the respective variation in growth and mortality. Moderate additional variation in mortality (26%) was attributable to differences in species composition. Age‐dependent biomass models showed that variation in forest biomass can be explained primarily by spatial gradients in growth that were unrelated to species composition. Species‐dependent patterns of mortality explained additional variation in biomass, with forests supporting less biomass when dominated by species that are highly susceptible to competition (e.g. Populus spp.) or to biotic disturbances (e.g. Abies balsamea). 相似文献