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81.
AIM: To investigate the effects of progesterone on the cell viability and expression of glucose transporter type 3(GLUT3) in PC12 cells injured by oxygen-glucose deprivation (OGD) in attempt to prove the neuroprotection of progesterone (PROG) against the hypoxic-ischemic injury in cultured cells in vitro. METHODS: Well-differentiated PC12 cells induced by nerve growth factor were randomly divided into 3 groups. In normal group, the cells were cultured without OGD treatment. In OGD group, the culture medium was replaced by glucose-free medium and the cells were transferred to a humidified incubation chamber flushed by a gas mixture of 95% N2 and 5% CO2 for 30 min. After that, the cells were fed with glucose-supplemented medium and cultured under normoxic condition for 24 h. In PROG+OGD group, the cells were given the same treatments as those in OGD group except that the medium contained progesterone at concentration of 10 nmol/L. Cellular morphological changes were observed after OGD for 30 min. The cell viability was assessed by WST-8 assay. The degree of the cell damage was evaluated by determining lactate dehydrogenase (LDH) leakage. The expression of GLUT3 at mRNA and protein levels was examined by RT-PCR and Western blotting, respectively. RESULTS: Progesterone attenuated the cellular swelling, decreased the leakage of LDH and improved the viability of PC12 cells injured by OGD (P<0.01). The expression of GLUT3 at mRNA and protein levels in PC12 cells in PROG+OGD group was significantly higher than that in OGD group (P<0.05). CONCLUSION: Progesterone has protective effect on in vitro cultured PC12 cells injured by OGD. The mechanism may be related to the up-regulation of GLUT3 protein. 相似文献
82.
AIM:To explore the effect of hyperhomocysteinemia on the Alzheimer-like pathological changes in the brain of aged rat. METHODS:The rats were treated with homocysteine(Hcy) by intravenous injection through vena caudalis with or without a simultaneous supplementation of folate and Vitamin B12(FB) in the drinking water for 28 weeks. The distribution and aggregation of tau protein were detected by Bielschowsky silver staining. Western blotting was used to determine the protein levels of tau phosphorylation, glycogen synthase kinase 3β(GSK-3β) and protein phosphatase 2A(PP2A). RESULTS:Treatment with Hcy induced hyperhomocysteinemia in aged rats and resulted in the formation of neurofibrillary tangles in the brain. Supplementation of FB effectively reduced the tangles. Hyperhomocysteinemia also induced Alzheimer-like tau hyperphosphorylation at multiple sites(Ser199/202and Ser396). Hyperhomocysteinemia activated GSK-3β and inhibited the activity of PP2A. Supplementation of FB alleviated the changes of tau and the activities of GSK-3β and PP2A. CONCLUSION:Supplementation of FB ameliorates the hyperhomocysteinemia-induced Alzheimer-like pathological changes of tau protein possibly through regulating the activity of GSK-3β and PP2A in aged rats. 相似文献
83.
CoCl_2对酸胁迫下多花黑麦草种子萌发及幼苗抗性的影响 总被引:1,自引:0,他引:1
本研究以多花黑麦草(Lolium multiflorum)为试验材料,采用不同浓度CoCl2溶液浸种的处理方法,就CoCl2对酸胁迫下多花黑麦草种子萌发、幼苗生长及抗逆性的影响进行了探讨。酸胁迫过程中多花黑麦草种子的发芽势、发芽率、发芽指数、活力指数、叶绿素含量和超氧化物歧化酶(SOD)活性随着处理液酸度的增强显著下降,根长抑制指数、丙二醛(MDA)含量、 O-2·产生速率和H2O2含量明显增大,过氧化物酶(POD)活性先增加后下降,细胞膜稳定指数(MSI)下降。0.1 mmol·L-1 CoCl2明显促进酸胁迫下多花黑麦草种子萌发,提高幼苗叶绿素含量、芽长、地上部干质量和SOD活性,降低MDA含量和POD活性。从整体上看,0.1 mmol·L-1 CoCl2对多花黑麦草种子萌发及幼苗生长有促进作用,并提高了多花黑麦草的抗酸胁迫能力。 相似文献
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《African Zoology》2013,48(2):291-298
The amphibian Amietophrynus regularis is distributed throughout equatorial Africa, with presumed introduced populations in the Cape Verde archipelago. Portions of the 12S and 16S rRNA mitochondrial regions of 30 specimens from Kenya, Uganda, Niger, Mali, Burkina-Faso, Ghana, Guinea-Bissau and Cape Verde were used to assess genetic diversity and to identify the most probable geographic origin for the introduction of this toad on the latter archipelago. Two lineages with 1.4% genetic divergence between them were identified in western and eastern Africa. All sequences from the different Cape Verde Islands were identical to each other and to the Guinea-Bissau samples, indicating, together with other historical evidences, that an anthropogenic introduction event probably occurred, possibly from Guinea-Bissau, but further work is needed to confirm this. As previously noted, several individuals from previous genetic studies seem to have been misidentified. 相似文献
88.
以西藏11个地区的牦牛类群共计110头为研究对象,采用PCR方法,首次从耳组织总DNA中扩增出了线粒体12SrRNA基因,并进行了序列测定及分析。结果表明,该基因的长962~965bp;序列分析表明12SrRNA基因有较高的进化速率,11个地区的牦牛品种同源性相对较高;对11种类群的牦牛及亚洲水牛、非洲水牛、欧洲野牛和家牛四种牛亚科的12SrRNA基因序列建立NJ和ME分子进化树,结果显示帕里牦牛、斯布牦牛、巴青牦牛、丁青牦牛、江达牦牛、工布江达牦牛、康布牦牛与桑日牦牛的亲缘关系最近。 相似文献
89.
克隆奶牛S100A12基因并在大肠杆菌中高效表达.采用RT-PCR扩增奶牛外周血白细胞中S100A12基因,构建原核表达载体pCold TF-S100A12,在大肠杆菌BL21(DE3)中IPTG诱导表达并纯化.SDS-PAGE和Westernblotting分析显示S100A12基因以融合蛋白形式表达,表达量占菌体总蛋白的46.7%,纯化的重组蛋白(80 mg/L).琼脂扩散法测定重组蛋白对乳腺炎主要致病菌大肠杆菌和金黄色葡萄球菌的抗菌活性.结果显示:重组蛋白对大肠杆菌有抗菌活性,而对金黄色葡萄球菌无抗菌活性.本研究为S100A12蛋白抗体制备及基因功能研究奠定了基础. 相似文献
90.
Nguyen Phuong Thao Nguyen Xuan Cuong Bui Thi Thuy Luyen Tran Hong Quang Tran Thi Hong Hanh Sohyun Kim Young-Sang Koh Nguyen Hoai Nam Phan Van Kiem Chau Van Minh Young Ho Kim 《Marine drugs》2013,11(8):2917-2926
Inflammation is important in biomedical research, because it plays a key role in inflammatory diseases including rheumatoid arthritis and other forms of arthritis, diabetes, heart disease, irritable bowel syndrome, Alzheimer’s disease, Parkinson’s disease, allergies, asthma, and even cancer. In the present study, we describe the inhibitory effect of crude extracts and steroids isolated from the starfish Astropecten polyacanthus on pro-inflammatory cytokine (Interleukin-12 (IL-12) p40, interleukin-6 (IL-6), and tumor necrosis factor α (TNF-α)) production in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs). Among those tested, compounds 5 and 7 showed potent inhibitory effects on the production of all three pro-inflammatory cytokines with IC50 values ranging from 1.82 ± 0.11 to 7.00 ± 0.16 μM. Potent inhibitory activities were also observed for compound 1 on the production of IL-12 p40 and IL-6 with values of 3.96 ± 0.12 and 4.07 ± 0.13 μM, respectively, and for compounds 3 and 4 on the production of IL-12 p40 with values of 6.55 ± 0.18 and 5.06 ± 0.16 μM, respectively. Moreover, compounds 2 (IC50 = 34.86 ± 0.31 μM) and 6 (IC50 = 79.05 ± 2.05 μM) exhibited moderate inhibitory effects on the production of IL-12 p40, whereas compounds 3 (IC50 = 22.80 ± 0.21 μM) and 4 (IC50 = 16.73 ± 0.25 μM) moderately inhibited the production of TNF-α and IL-6, respectively. 相似文献