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991.
992.
Obesity and its associated metabolic disorders such as diabetes, hepatic steatosis and chronic heart diseases are affecting billions of individuals. However there is no satisfactory drug to treat such diseases. In this study, we found that alisol A, a major active triterpene isolated from the Chinese traditional medicine Rhizoma Alismatis, could significantly attenuate high‐fat‐diet‐induced obesity. Our biochemical detection demonstrated that alisol A remarkably decreased lipid levels, alleviated glucose metabolism disorders and insulin resistance in high‐fat‐diet‐induced obese mice. We also found that alisol A reduced hepatic steatosis and improved liver function in the obese mice model.In addition, protein expression investigation revealed that alisol A had an active effect on AMPK/ACC/SREBP‐1c pathway. As suggested by the molecular docking study, such bioactivity of alisol A may result from its selective binding to the catalytic region of AMPK.Therefore, we believe that Alisol A could serve as a promising agent for treatment of obesity and its related metabolic diseases.  相似文献   
993.
994.
Zhang L  Meng F  Li Y  Kang M  Guo X  Xu B 《BMB reports》2012,45(5):293-298
The p38 mitogen-activated protein kinase (MAPK) is involved in various processes, including stress responses, development, and differentiation. However, little information on p38 MAPK in insects is available. In this study, a p38 MAPK gene, Accp38b, was isolated from Apis cerana cerana and characterized. The quantitative real-time PCR (Q-PCR) analysis revealed that Accp38b was induced by multiple stressors. Notably, the expression of Accp38b was relatively higher in the pupae phase than in other developmental phases. During the pupae phase, Accp38b expression was higher in the thorax than in the head and abdomen and higher in the fat body than in the muscle and midgut. Immunohistochemisty showed significant positive staining of Accp38b in sections from the brain, eyes, fat body, and midgut of A. cerana cerana. These results suggest that Accp38b may play a crucial role in stress responses and have multiple aspects function during development.  相似文献   
995.
Adult T-cell leukemia (ATL) and HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP) are associated with Human T-cell lymphotropic virus type 1 (HTLV-1) infection. The viral transactivator, Tax is able to mediate the cell cycle progression by targeting key regulators of the cell cycle such as p21/waf1, p16/ink4a, p53, cyclins D1-3/cdk complexes, and the mitotic spindle checkpoint MAD apparatus, thereby deregulating cellular DNA damage and checkpoint control. Genome expression profiling of infected cells exemplified by the development of DNA microarrays represents a major advance in genome-wide functional analysis. Utilizing cDNA microarray analysis, we have observed an apparent opposing and paradoxical regulatory network of host cell gene expression upon the introduction of DNA damage stress signal. We find the apparent induction of cell cycle inhibitors, and pro- as well as anti-apoptotic gene expression is directly linked to whether cells are at either G1, S, or G2/M phases of the cell cycle. Specifically, a G1/S block is induced by p21/waf1 and p16/ink4a, while pro-apoptotic expression at S, and G2/M is associated with caspase activation, and anti-apoptotic gene expression is associated with up regulation of Bcl-2 family member, namely bfl-1 gene. Therefore, the microarray results indicating expression of both pro- and anti-apoptotic genes could easily be explained by the particular stage of the cell cycle. Mechanism and the functional outcome of induction for both pathways are discussed.  相似文献   
996.
997.
Using the fluorescent dyes calcein and alcian blue, we stained the F3 generation of chemically (ENU) mutagenized zebrafish embryos and larvae, and screened for mutants with defects in bone development. We identified a mutant line, bone calcification slow (bcs), which showed delayed axial vertebra calcification during development. Before 4–5 days post-fertilization (dpf), the bcs embryos did not display obvious abnormalities in bone development (i.e., normal number, size and shape of cartilage and vertebrae). At 5–6 dpf, when vertebrae calcification starts, bcs embryos began to show defects. At 7 dpf, for example, in most of the bcs embryos examined, calcein staining revealed no signals of vertebrae mineralization, whereas during the same developmental stages, 2–14 mineralized vertebrae were observed in wild-type animals. Decreases in the number of calcified vertebrae were also observed in bcs mutants when examined at 9 and 11 dpf, respectively. Interestingly, by 13 dpf the defects in bcs mutants were no longer evident. There were no significant differences in the number of calcified vertebrae between wild-type and mutant animals. We examined the expression of bone development marker genes (e.g., Sox9b, Bmp2b, and Cyp26b1, which play important roles in bone formation and calcification). In mutant fish, we observed slight increases in Sox9b expression, no alterations in Bmp2b expression, but significant increases in Cyp26b1 expression. Together, the data suggest that bcs delays axial skeletal calcification, but does not affect bone formation and maturation.  相似文献   
998.
川鄂山茱萸不同部位中熊果酸的含量测定   总被引:2,自引:0,他引:2  
目的:测定川鄂山茱萸不同部位中熊果酸的含量,筛选含量最高的部位,为充分利用川鄂山茱萸野生资源提供依据。方法:采用SymmetrySheild TM RP18色谱柱4.6mm×250mm,5μm);乙腈-水-磷酸(80∶20∶0.1)为流动相;检测波长为206nm;流速为1.0mL/min;柱温为30℃。结果:熊果酸在0.42mg~2.94mg范围内呈良好的线性关系(r=0.9998),平均回收率为96.27%,RSD为1.4%。结论:川鄂山茱萸不同部位均含有熊果酸,且含量有明显差别。川鄂山茱萸总苞片的熊果酸含量为1.1044%,有一定的开发价值。  相似文献   
999.
Zhang Z  Wei T  Hou J  Li G  Yu S  Xin W 《Life sciences》2003,72(22):2465-2472
Tetramethylpyrazine is one of the active ingredients of the Chinese herb Ligusticum wallichii Franchat. By electron spin resonance spin trapping methods, effects of tetramethylpyrazine on superoxide anion and nitric oxide generated by human polymorphonuclear leukocytes were studied. During the respiratory burst of polymorphonuclear leukocytes induced by N-formylmethionyl-leucyl-phenylalanine, tetramethylpyrazine scavenges superoxide anion dose-dependently, and decreases the production of nitric oxide significantly, but shows no influence on oxygen consumption. These results suggest that the effective protection of tetramethylpyrazine against ischemic brain injury might be due to its scavenging of reactive oxygen species and regulation on nitric oxide production, and consequent prevention of peroxynitrite formation.  相似文献   
1000.
红掌原产于南美洲热带雨林,其具有色彩艳丽的佛焰苞,在适宜的条件下可周年开花,是一种具有极高观赏价值的盆花和切花植物.夏季高温严重影响红掌的生长和观赏价值,增加了红掌的种植成本.对高温胁迫影响红掌外观形态、光合作用、细胞膜热稳定性、渗透调节物质、保护酶活性进行了讨论分析,对高温褪色机理及其应对措施进行了归纳总结,以期为进...  相似文献   
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