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151.
目的分离培养普通卷甲虫肠道中的可培养细菌,筛选有产消化酶活性的细菌,推测其在协助普通卷甲虫消化食物中的作用。方法通过传统分离培养法分离普通卷甲虫肠道中的可培养细菌,利用平板透明圈法筛选产淀粉酶、蛋白酶、纤维素酶和脂肪酶活性的细菌,利用水解圈与菌落直径的比值,比较不同细菌的产消化酶活性。利用SPSS 20.0软件进行统计学分析,组间比较采用单因素方差分析。结果在普通卷甲虫肠道中分离出4个属9种细菌,其中气单胞菌属3种,假芽胞杆菌属和柠檬酸杆菌属各2种,芽胞杆菌属和假单胞菌属各1种。9种细菌中弗氏柠檬酸杆菌、豚鼠气单胞菌、南海假芽胞杆菌等3种细菌可产蛋白酶,嗜水气单胞菌、波特卡伦柠檬酸杆菌、水生气单胞菌、豚鼠气单胞菌和南海假芽胞杆菌等5种细菌可产纤维素酶,嗜水气单胞菌、波特卡伦柠檬酸杆菌、印度芽胞杆菌、水生气单胞菌、嗜盐假芽胞杆菌、豚鼠气单胞菌和南海假芽胞杆菌等7种细菌可产淀粉酶,未筛选到产脂肪酶细菌。统计学分析表明,3种产蛋白酶细菌和5种产纤维素酶细菌的产酶活性差异无统计学意义。而7种产淀粉酶细菌产酶的活力间差异有统计学意义,水生气单胞菌的产淀粉酶活性能力最强。结论普通卷甲虫肠道可培养细菌结构简单,但有消化酶活性的细菌种类多,5种细菌有产2种以上消化酶功能,说明肠道细菌可能在普通卷甲虫食物消化中起着重要作用。 相似文献
152.
Li-Ping Nan Feng Wang Yang Liu Zhong Wu Xin-Min Feng Jun-Jian Liu Liang Zhang 《World journal of stem cells》2020,12(12):1603-1622
BACKGROUNDTo date, there has been no effective treatment for intervertebral disc degeneration (IDD). Nucleus pulposus-derived mesenchymal stem cells (NPMSCs) showed encouraging results in IDD treatment, but the overexpression of reactive oxygen species (ROS) impaired the endogenous repair abilities of NPMSCs. 6-gingerol (6-GIN) is an antioxidant and anti-inflammatory reagent that might protect NPMSCs from injury.AIMTo investigate the effect of 6-GIN on NPMSCs under oxidative conditions and the potential mechanism.METHODSThe cholecystokinin-8 assay was used to evaluate the cytotoxicity of hydrogen peroxide and the protective effects of 6-GIN. ROS levels were measured by 2´7´-dichlorofluorescin diacetate analysis. Matrix metalloproteinase (MMP) was detected by the tetraethylbenzimidazolylcarbocyanine iodide assay. TUNEL assay and Annexin V/PI double-staining were used to determine the apoptosis rate. Additionally, autophagy-related proteins (Beclin-1, LC-3, and p62), apoptosis-associated proteins (Bcl-2, Bax, and caspase-3), and PI3K/Akt signaling pathway-related proteins (PI3K and Akt) were evaluated by Western blot analysis. Autophagosomes were detected by transmission electron microscopy in NPMSCs. LC-3 was also detected by immunofluorescence. The mRNA expression of collagen II and aggrecan was evaluated by real-time polymerase chain reaction (RT-PCR), and the changes in collagen II and MMP-13 expression were verified through an immunofluorescence assay.RESULTS6-GIN exhibited protective effects against hydrogen peroxide-induced injury in NPMSCs, decreased hydrogen peroxide-induced intracellular ROS levels, and inhibited cell apoptosis. 6-GIN could increase Bcl-2 expression and decrease Bax and caspase-3 expression. The MMP, Annexin V-FITC/PI flow cytometry and TUNEL assay results further confirmed that 6-GIN treatment significantly inhibited NPMSC apoptosis induced by hydrogen peroxide. 6-GIN treatment promoted extracellular matrix (ECM) expression by reducing the oxidative stress injury-induced increase in MMP-13 expression. 6-GIN activated autophagy by increasing the expression of autophagy-related markers (Beclin-1 and LC-3) and decreasing the expression of p62. Autophagosomes were visualized by transmission electron microscopy. Pretreatment with 3-MA and BAF further confirmed that 6-GIN-mediated stimulation of autophagy did not reduce autophagosome turnover but increased autophagic flux. The PI3K/Akt pathway was also found to be activated by 6-GIN. 6-GIN inhibited NPMSC apoptosis and ECM degeneration, in which autophagy and the PI3K/Akt pathway were involved.CONCLUSION6-GIN efficiently decreases ROS levels, attenuates hydrogen peroxide-induced NPMSCs apoptosis, and protects the ECM from degeneration. 6-GIN is a promising candidate for treating IDD. 相似文献
153.
Jun Sun Xiaoping Chen Mantang Wang Jinlong Li Quanlin Zhong Dongliang Cheng 《Ecology and evolution》2020,10(23):13395
Understanding the scaling between leaf size and leafing intensity (leaf number per stem size) is crucial for comprehending theories about the leaf costs and benefits in the leaf size–twig size spectrum. However, the scaling scope of leaf size versus leafing intensity changes along the twig leaf size variation in different leaf habit species remains elusive. Here, we hypothesize that the numerical value of scaling exponent for leaf mass versus leafing intensity in twig is governed by the minimum leaf mass versus maximum leaf mass (M min versus M max) and constrained to be ≤−1.0. We tested this hypothesis by analyzing the twigs of 123 species datasets compiled in the subtropical mountain forest. The standardized major axis regression (SMA) analyses showed the M min scaled as the 1.19 power of M max and the ‐α (−1.19) were not statistically different from the exponents of M min versus leafing intensity in whole data. Across leaf habit groups, the M max scaled negatively and isometrically with respect to leafing intensity. The pooled data''s scaling exponents ranged from −1.14 to −0.96 for M min and M max versus the leafing intensity based on stem volume (LIV). In the case of M min and M max versus the leafing intensity based on stem mass (LIM), the scaling exponents ranged from −1.24 to −1.04. Our hypothesis successfully predicts that the scaling relationship between leaf mass and leafing intensity is constrained to be ≤−1.0. More importantly, the lower limit to scaling of leaf mass and leafing intensity may be closely correlated with M min versus M max. Besides, constrained by the maximum leaf mass expansion, the broad scope range between leaf size and number may be insensitive to leaf habit groups in subtropical mountain forest. 相似文献
154.
Cross Adam T. Stevens Jason C. Sadler Rohan Moreira-Grez Benjamin Ivanov Dmitry Zhong Hongtao Dixon Kingsley W. Lambers Hans 《Plant and Soil》2021,460(1-2):163-176
Plant and Soil - In water-limited areas, shrubs influence biological soil crust (biocrust) composition and diversity via soil microenvironment alterations and through modifying biotic interactions... 相似文献
155.
156.
157.
Molecular Biology Reports - Chemosensory receptors in the dendritic membrane of olfactory cells are critical for the molecular recognition and discrimination of odorants. Tropidothorax elegans is a... 相似文献
158.
Wang Lingfeng Guo Ying Ye Jiayi Pan Zeyue Hu Peihao Zhong Xiaoming Qiu Fengmei Zhang Danni Huang Zhen 《Neurochemical research》2021,46(7):1869-1880
Neurochemical Research - Piceatannol is a natural plant-derived compound with protective effects against cardiovascular diseases. However, its effect on cerebral ischaemia–reperfusion injury... 相似文献
159.
Zhong Zhe Chen Weijie Gao Huan Che Ningning Xu Min Yang Lanqing Zhang Yingfang Ye Min 《Neurochemical research》2021,46(11):3050-3058
Neurochemical Research - Gut microbiota is closely related to the Parkinson’s disease (PD) pathogenesis. Additionally, aggregation of α-synuclein (α-syn) is central to PD... 相似文献
160.
Minh Thuy Nguyen Lu Haoran Zhang Pengmin Li Wenfeng Zhong Shihua Ding Xiaodong Xiao Jialei Li Qiang 《Plant Molecular Biology Reporter》2021,39(4):792-800
Plant Molecular Biology Reporter - Plant SnRK1 kinases have been reported to participate in regulating many aspects of plant biology including resistance to biotic and abiotic stresses. Wild... 相似文献