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991.
BackgroundPancreatic inflammation plays a key role in diabetes pathogenesis and progression. Urolithin A (UA), an intestinal flora metabolite of pomegranate, has anti-diabetic, anti-inflammatory and kidney protection effects among others. However, its effects on pancreatic inflammation and the potential mechanisms have not been clearly established.PurposeThis study aimed at investigating the molecular mechanisms of UA anti-pancreatic inflammation under a diabetic environment.MethodsDiabetes induction in male C57BL/6 mice was achieved by a high fat diet and intraperitoneal streptozotocin injections. Then, diabetic mice were orally administered with UA for 8 weeks. In vitro, endoplasmic reticulum stress and MIN6 pancreatic β cell inflammation were induced using 25 mM glucose and 0.5 mM palmitic acid. The effects of UA were evaluated by immunohistochemistry, Western blot, and enzyme linked immunosorbent assays. Finally, the underlying mechanisms were elucidated using an autophagy inhibitor (chloroquine, CQ) and an AMPK inhibitor (dorsomorphin dihydrochloride).ResultsUA significantly inhibited IL-1β secretion and TXNIP/NLRP3 expression in the pancreas of diabetic mice and in MIN6 pancreatic cells. UA downregulated the ER stress protein, p-PERK, and promoted AMPK phosphorylation. UA activated autophagy to inhibit TXNIP/NLRP3 IL-1β inflammatory signal, an effect that was reversed by CQ. Dorsomorphin 2HCL, reversed the autophagy-activation and anti-inflammatory effects of UA. Verapamil, clinically applied as an antiarrhythmic drug, is a TXNIP inhibitor for prevention of beta cell loss and diabetes development, but limited by its cardiac toxicity. In this study, verapamil (as positive control) inhibited NLRP3 /IL-1β signaling in MIN6 cells. Inhibitory effects of UA on TXNIP and IL-1β were weaker than those of verapamil (both at 50 μM, p < 0.05, p < 0.01). Conversely, inhibitory effects of UA on p62 were stronger, relative to those of verapamil (p < 0.05), and there were no differences in AMPK activation and LC3 enhancement effects between UA and verapamil.ConclusionUA is a potential anti-pancreatic inflammation agent that activates AMPK and autophagy to inhibit endoplasmic reticulum stress associated TXNIP/NLRP3/IL-1β signal pathway.  相似文献   
992.
International Journal of Peptide Research and Therapeutics - Chickpea (Cicer arietinum L.) is the second most widely cultivated leguminous plant in the world. In this study, the chickpea sprout...  相似文献   
993.
The chemical profile and allelopathic action of the volatiles produced by Artemisia selengensis were studied. Artemisia selengensis was found to release volatile chemicals to the environment to influence other plants’ growth, which suppressed the root length of Amaranthus retroflexus and Poa annua by 50.46 % and 87.83 % under 80 g/1.5 L treatment, respectively. GC/MS analysis led to the identification of 41 compounds (by hydrodistillation, HD) and 48 compounds (by headspace solid-phase microextraction, HS-SPME), with eucalyptol (15.45 % by HD and 28.09 % by HS-SPME) being detected as the most abundant constituent. The essential oil (EO) of A. selengensis completely inhibited the seed germination of A. retroflexus and P. annua at 1 mg/mL and 0.5 mg/mL, respectively. However, eucalyptol displayed much weaker activity compared with the EO, indicating that other less abundant constituents might contribute significantly to the EO's activity. Our study is the first report on the phytotoxicity of A. selengensis EO, suggesting that A. selengensis might release allelopathic volatile agents into the environment that negatively affect other plants’ development so as to facilitate its own dominance; the potential value of utilizing A. selengensis EO as an environmentally friendly herbicide is also discussed.  相似文献   
994.
为明确七星瓢虫成虫对棉蚜的自然控制能力,本文通过密度-天敌双因素控制试验分析了不同棉蚜初始密度(200头/株、400头/株、800头/株)和不同七星瓢虫数量(0头、1头、2头、4头)组合处理下棉蚜的种群动态;使用棉蚜种群增长率、益害比、控制效果等指标评估了天敌的控制能力,并建立简单的模型来明确天敌有效控制棉蚜的益害比.结果表明,七星瓢虫和棉蚜初始密度显著影响着棉蚜的种群数量,且两者存在交互作用;益害比与控制效果存在显著的正相关性,种群增长率与控制效果又存在显著的负相关性.投放七星瓢虫5 d后,当益害比达到1∶720以下时,七星瓢虫可有效控制棉蚜(种群增长率r≤0),此时控制效果达44%以上;此外,当益害比为1∶671时,七星瓢虫对棉蚜种群的控制效果达50%,益害比低于1∶360以下时,七星瓢虫对棉蚜种群的控制效果可达80%以上.因此,本文通过控制试验建立了七星瓢虫成虫控制棉蚜的防治指标,可以依据该阈值来指导田间棉蚜的综合防治.  相似文献   
995.
ABI3是ABA信号通路中关键的转录调控因子, 参与种子休眠、质体发育及苔藓耐干等重要生理过程, 在植物抗逆中发挥关键作用。以荒漠耐干苔藓——齿肋赤藓(Syntrichia caninervis)为材料, 克隆了抗逆基因ScABI3并获得3个独立的pCAMBIA1301-ScABI3转基因拟南芥(Arabidopsis thaliana)纯合株系。结果表明, 转基因拟南芥叶片气孔孔径增大, 单位面积气孔数量减少, 植株水分利用效率提高; 在干旱处理14天后转基因拟南芥植株存活率显著高于野生型, 离体叶片失水率显著低于野生型。进一步研究发现, ScABI3转基因拟南芥通过提高自身活性氧(ROS)清除能力增强植株抗旱性。研究结果可为开发利用荒漠植物基因资源培育抗逆作物品种奠定基础。  相似文献   
996.
目的:研究针灸联合十八段锦治疗对中风偏瘫患者运动功能的影响。方法:选择2017年1月~2019年12月我院中医科针灸门诊针灸治疗的201例中风偏瘫患者,随机分为两组。对照组采用常规治疗,观察组采用针灸联合十八段锦治疗。治疗前后,比较两组的血清基质金属蛋白酶-9 (Matrix metalloproteinases-9,MMP-9)、促红细胞生成素(Erythropoietin,EPO)、同型半胱氨酸(Homocysteine,Hcy)水平、Tinetti步态评估量表(Tinetti gait assessment,TGA)以及功能性步行量表(functional ambulation category,FAC)评分。结果:观察组中风偏瘫患者的有效率明显高于对照组(P<0.05);治疗后,两组的血清MMP-9、EPO、Hcy水平均明显降低(P<0.05),FAC分级和TGA评分均明显升高(P<0.05),且观察组上述指标低于对照组(P<0.05)。结论:针灸联合十八段锦治疗能明显改善中风偏瘫患者的运动功能,提高疗效,其机制可能与降低血清MMP-9、EPO、Hcy水平有关,值得进行推广。  相似文献   
997.
四种荒漠植物保色浸渍标本实验研究   总被引:1,自引:0,他引:1  
冯缨  谷忠义  闫小飞 《植物研究》2008,28(6):764-766
利用浸制标本能较长时间地保持原植物的形态、色泽、质地。以CuSO4溶液浓度的不同梯度,选用L9(34)表进行4种荒漠植物保色浸渍标本正交试验研究,结果表明梭梭(Haloxylon ammodendron(C.A.Mey.)Bge.)在15%CuSO4、沙拐枣(Calligonum mongolicum Turcz.)在10%CuSO4溶液、中麻黄(Ephedra intermedia Schrenk)在5%CuSO4溶液、多枝柽柳(Tamarix ramosissima Ledeb.)在5%CuSO4溶液中浸渍效果最佳,推导出的最优配方与试验结果有很好的拟合性,有一定的实验价值。  相似文献   
998.
In this paper, chlorophytes collected from 253 biological soil crust samples in Gurbantunggut Desert in Xinjiang Autonomous Region, China were studied by field investigation and microscopical observation in lab. The flora composition, ecological distribution of chlorophytes in the desert and dynamic changes of species composition of chlorophytes in different developing stages of biological soil crusts are preliminarily analyzed. Results showed that there were 26 species belonging to 14 genera and 10 families, in which unicellular chlorophytes were dominant. There existed some differences in distribution of varied sand dune positions. The taxa of chlorophytes in leeward of sand dunes are most abundant, but the taxa in windward, interdune and the top of sand dunes reduced gradually. Chlorophytes were mainly distributed within the crust and the taxa of chlorophytes decrease obviously under the crust. In the devel-oping stages of the biological soil crust, species diversity of chlorophytes changed a little, but species composition pre-sented some differences. Chlorococcum humicola, Chlorella vulgaris, Chlamydomonas ovalis and Chlamydomonas sp. nearly existed in all developing stages of biological crusts. In several former stages of the biological soil crust there were spherical chlorophytes and filamentous ones. When moss crust formed, filamentous chlorophytes disappeared, such as Microspora and Ulothrix.  相似文献   
999.
Fertilization has been shown to have suppressive effects on arbuscular mycorrhizal fungi (AMF) and root hemiparasites separately in numerous investigations, but its effects on AMF in the presence of root hemiparasites remain untested. In view of the contrasting nutritional effects of AMF and root hemiparasites on host plants, we tested the hypothesis that fertilization may not show strong suppressive effects on AMF when a plant community was infested by abundant hemiparasitic plants. Plants and soil samples were collected from experimental field plots in Bayanbulak Grassland, where N and P fertilizers had been applied for three continuous years for control against a spreading root hemiparasite, Pedicularis kansuensis. Shoot and root biomass of each plant functional group were determined. Root AMF colonization levels, soil spore abundance, and extraradical hyphae length density were measured for three soil depths (0-10 cm, 10-20 cm, 20-30 cm). Partial 18S rRNA gene sequencing was used to detect AMF diversity and community composition. In addition, we analyzed the relationship between relative abundance of different AMF genera and environmental factors using Spearman's correlation method. In contrast to suppressive effects reported by many previous studies, fertilization showed no significant effects on AMF root colonization or AMF species diversity in the soil. Instead, a marked increase in soil spore abundance and extraradical hyphae length density were observed. However, fertilization altered relative abundance and AMF composition in the soil. Our results support the hypothesis that fertilization does not significantly influence the abundance and diversity of AMF in a plant community infested by P. kansuensis.  相似文献   
1000.
新疆伊贝母有效成分含量与气候因子相关性分析   总被引:1,自引:0,他引:1  
应用系统相关分析法和灰色关联度分析法,研究伊贝母(新疆贝母Fritillaria walujewii、伊犁贝母F. pallidiflora)有效成分含量与气候因子的相关性,筛选影响其质量的主导因子。结果表明,新疆不同产地气候因子存在较大差异,伊贝母总生物碱和西贝母碱含量与年均气温、地面温度、日照时数、相对湿度、降水量等5个气候因子无显著相关性;西贝母碱苷含量与年均相对湿度有极显著正相关(P<0.01),与年均地面温度有显著正相关(P<0.05),与年均日照时数有显著负相关(P<0.05);水溶性成分腺苷含量与年均降水量和地面温度均有显著正相关(P<0.05);水溶性成分β-胸苷含量与年均气温、相对湿度和地面温度均有显著正相关(P<0.05),与年均日照时数有显著负相关(P<0.05)。上述相关分析结果与灰色关联度分析结果一致。年均气温、降水量、相对湿度和地面温度升高有助于伊贝母中西贝母碱苷、腺苷和β-胸苷的形成与积累,年均日照时数升高则抑制西贝母碱苷和β-胸苷的形成与积累。伊贝母最佳适宜生长的气候条件为年均气温13~27℃,降水量169~288 mm,相对湿度55%~66%,日照时数2140~2547 h,地面温度26~41 ℃。  相似文献   
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