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901.
Xu Wei Shuangshuang Guo Lin-Feng Gong Gaoyang He Ka-Lai Pang 《Geomicrobiology journal》2018,35(9):790-797
The diversity of fungi in the marine environment has been extensively studied, but their denitrification activity has rarely been reported to date. In the present study, we used six different media to isolate fungi from 10 sediment samples collected at five different locations of the East Pacific Ocean with water depths ranging from 4545 to 7068?m. Fungal identification and phylogenetic diversity analysis were conducted based on morphological characteristics and internal transcribed spacers of ribosomal DNA (ITS-rRNA) sequencing. A total of 106 fungal isolates, belonging to 12 genera, including Aspergillus (five strains), Aureobasidium (three strains), Candida (two strains), Cladosporium (56 strains), Cystobasidium (one strain), Devriesia (nine strains), Knufia (one strain), Nigrospora (three strains), Penicillium (18 strains), Rhodotorula (four strains), Sarocladium (three strains), and unclassified Xylariales (one strain) were obtained. The most dominant culturable genus was Cladosporium. One possible novel fungal strains showed less than 97% similarity to their closest matches of unclassified Xylariales in the Genbank. In addition, we used nirK gene as the molecular marker to detect denitrifying fungi among the cultivable fungal isolates. The nirK gene was detected in Aspergillus niger and Penicillium chrysogenum. Our research indicated that diverse fungi from the deep sea sediments of the East Pacific Ocean and highlighted the involvement of these fungi in denitrification process. 相似文献
902.
903.
There is a global consensus on the fact that human activities are increasingly eroding biodiversity, especially in many ecologically rich regions of the world. Quantifying these biodiversity losses over large administrative areas, along with the impacts of the respective driving factors is necessary for biodiversity conservation. In this study, we used readily available spatial data on infrastructure, fragmentation, and land use together with ecological data on terrestrial arthropods (as species surrogate) to carry out spatial assessment and mapping of biodiversity values in the Western Region of Ghana, a highly degraded part of the West African biodiversity hotspot. Compared with its pristine condition, our results show that the region has a remaining mean species abundance (MSA) of approximately 52%, indicating a loss of 48% due to anthropogenic activities (mainly cocoa and oil palm farming). Areas of national protection (i.e. national parks and forest reserves) did not prove to have much promise for biodiversity conservation in the region since many were found to have low MSA values. Moreover, according to our arthropod data, no areas of high MSA values were found outside protected areas. However, because the thick, continuous, structurally complex canopies of these orchards responsible for the biodiversity loss provide natural connectivity between protected reserves, diversification of understory vegetation and a reduction in the use of agrochemicals particularly weedicides and pesticides may yield significant conservation outcomes. 相似文献
904.
905.
Dan Du Tao Jin Rui Zhang Liqiang Hu Zhihua Xing Na Shi Yan Shen Meng Gong 《Bioorganic & medicinal chemistry letters》2017,27(6):1467-1470
One new bibenzyl (1) and one new phenanthrene (2), together with two known bibenzyls (3–4) and four known diarylheptanoids (5–8) were isolated from the rhizomes of Dioscorea zingiberensis. The structures of 1–2 were elucidated by spectroscopic methods including 1D and 2D NMR. Phenols 1–8 were evaluated for their anti-pancreatitic activities on sodium taurocholate (NaT)-induced pancreatic acinars necrosis. Notably, 0.5 mM of compound 6 exhibited comparable inhibitory effect with 5 mM of caffeine. Furthermore, compound 6 prevented the ATP depletion and excessive ROS production which could be also involved in mitochondria-mediated injuries in acute pancreatitis. As a result, compound 6 has been demonstrated to be a potential candidate for mediating mitochondrial dysfunction to prevent pancreatic necrosis. This study is also the first report on the isolation of bibenzyls and diarylheptanoids from this plant. 相似文献
906.
Xiaoqing Sun Zexin Hong Moyi Liu Su Guo Di Yang Yong Wang Tian Lan Linyu Gao Hongxia Qi Ping Gong Yajing Liu 《Bioorganic & medicinal chemistry》2017,25(10):2800-2810
A series of novel tetrahydropyrazolopyridone derivatives containing 1,3,4-triazole, triazolylmethyl, and partially saturated heterocyclic moieties as P2 binding element was designed, synthesized, and evaluated in vitro for anticoagulant activity in human and rabbit plasma. All compounds showed moderate to significant potency, and compounds 15b, 15c, 20b, 20c, and 22b were further examined for their inhibitory activity against human FXa in vitro. While compounds 15c and 22b were tested for rat venous thrombosis in vivo. The most promising compound 15c, with an IC50 (FXa) value of 0.14 μM and 98% inhibition rate, warranted further investigation as an FXa inhibitor. 相似文献
907.
Han?Y.?Gong Yang?Li Gen?Fang Dao?H.?Hu Zhao?H.?Wang Guang?H.?Yu Yang?S.?LiEmail author 《Plant Molecular Biology Reporter》2017,35(6):619-633
Two cyanobacterial genes ccaA and FBP/SBPase related to CO2 hydration and Calvin cycle were induced into rice plants. Three homologous transgenic strains were generated with ccaA and FBP/SBPase alone or in combination independently and grown under field conditions. The biochemical, physiological, and leaf anatomic results indicated that stomatal and mesophyll conductance to CO2, net photosynthetic rate, carboxylation efficiency, and other physiological and biochemical parameters increased significantly in the overexpression strains with FBP/SBPase and CcaA + FBP/SBPase but not in the CcaA strain. Leaf anatomy structure showed no significant modifications between the transgenic and wild-type strains. The CcaA protein was shown to be located in the cytoplasm. These results showed that the effect on improving photosynthetic capacity by FBP/SBPase was better than by CcaA, and only when CcaA was co-transformed with FBP/SBPase was the synergistic effect observed. The multigene-stacking approaches and their synergistic action for improving the photosynthetic capacity in rice are discussed. 相似文献
908.
Haipeng Gong 《Proteins》2017,85(12):2162-2169
Helix‐helix interactions are crucial in the structure assembly, stability and function of helix‐rich proteins including many membrane proteins. In spite of remarkable progresses over the past decades, the accuracy of predicting protein structures from their amino acid sequences is still far from satisfaction. In this work, we focused on a simpler problem, the prediction of helix‐helix interactions, the results of which could facilitate practical protein structure prediction by constraining the sampling space. Specifically, we started from the noisy 2D residue contact maps derived from correlated residue mutations, and utilized ridge detection to identify the characteristic residue contact patterns for helix‐helix interactions. The ridge information as well as a few additional features were then fed into a machine learning model HHConPred to predict interactions between helix pairs. In an independent test, our method achieved an F‐measure of ~60% for predicting helix‐helix interactions. Moreover, although the model was trained mainly using soluble proteins, it could be extended to membrane proteins with at least comparable performance relatively to previous approaches that were generated purely using membrane proteins. All data and source codes are available at http://166.111.152.91/Downloads.html or https://github.com/dpxiong/HHConPred . 相似文献
909.
Fisetin provides antidepressant effects by activating the tropomyosin receptor kinase B signal pathway in mice 下载免费PDF全文
Yamin Wang Bin Wang Jiaqi Lu Haixia Shi Siyi Gong Yufan Wang Ronald C. Hamdy Balvin H. L. Chua Lingli Yang Xingshun Xu 《Journal of neurochemistry》2017,143(5):561-568
910.
Rui Li Yanqing Wu Shuang Zou Xiaofang Wang Yiyang Li Ke Xu Fanghua Gong Yanlong Liu Jian Wang Yi Liao Xiaokun Li Jian Xiao 《Neurochemical research》2017,42(11):3005-3018
Diabetic peripheral neuropathy (DPN) is one of the most common and troublesome complications of diabetes mellitus. It has been demonstrated that nerve growth factor (NGF) exerts a pivotal role in the regulation of neuronal growth and the promotion of DPN recovery. However, the exact molecular mechanisms are not well understood. Recent studies have indicated that as a novel therapeutic target, endoplasmic reticulum (ER) stress participates in the onset and progression of DPN. In the present study, it has been demonstrated that NGF prevents the sciatic nerve from degeneration and demyelination in DPN rats. Thus, RSC 96 cells, which retain the characteristic features of Schwann cells (SCs), were cultured in medium containing 30 mM glucose (high glucose, HG) to mimic SCs in DPN mice. The 50-ng/ml dose of NGF was identified to be the optimal concentration for treating an excessive ER stress level under HG conditions for 24 h. We found that NGF treatment significantly inhibits HG-induced ER stress and subsequently suppresses ER-related apoptosis. Further, NGF administration also activates the upstream signaling pathway of ER stress, PI3K/Akt/GSK3β signaling and ERK1/2 signaling. Co-treatment with the PI3K inhibitor LY294002 or ERK1/2 inhibitor U0126 significantly reverses the protective role of NGF on HG-induced excessive ER stress and subsequent apoptosis. These observations suggest that the neuroprotective role of NGF in DPN is mediated by the inhibition of excessive ER stress via the activation of the PI3K/Akt/GSK3β and ERK1/2 signaling pathways. 相似文献