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Adipose tissue macrophage (ATM) plays a central role in obesity-associated inflammation and insulin resistance. Quercetin, a dietary flavonoid, possesses anti-inflammation and anti-insulin resistance properties. However, it is unclear whether quercetin can alleviate high-fat diet (HFD)-induced ATM infiltration and inflammation in mice. In this study, 5-week-old C57BL/6 mice were fed low-fat diet, HFD, or HFD with 0.l% quercetin for 12 weeks, respectively. Dietary quercetin reduced HFD-induced body weight gain and improved insulin sensitivity and glucose intolerance in mice. Meanwhile, dietary quercetin enhanced glucose transporter 4 translocation and protein kinase B signal in epididymis adipose tissues (EATs), suggesting that it heightened glucose uptake in adipose tissues. Histological and real-time PCR analysis revealed that quercetin attenuated mast cell and macrophage infiltration into EATs in HFD-fed mice. Dietary quercetin also modified the phenotype ratio of M1/M2 macrophages, lowered the levels of proinflammatory cytokines, and enhanced adenosine monophosphate-activated protein kinase (AMPK) α1 phosphorylation and silent information regulator 1 (SIRT1) expression in EATs. Further, using AMPK activator 5-aminoimidazole-4-carboxamide-1-β4-ribofuranoside and inhibitor Compound C, we found that quercetin inhibited polarization and inflammation of mouse bone marrow-derived macrophages through an AMPKα1/SIRT1-mediated mechanism. In conclusion, dietary quercetin might suppress ATM infiltration and inflammation through the AMPKα1/SIRT1 pathway in HFD-fed mice  相似文献   
997.

Background

The coverage of HIV testing among Chinese men who have sex with men (MSM) remains low after the scale-up of free HIV testing at government-sponsored testing sites. We evaluated the feasibility of home-based HIV self-testing and the willingness to be HIV tested at community-based organizations (CBO).

Methods

We recruited MSM via on-line advertisement, where they completed an on-line informed consent and subsequent questionnaire survey. Eligible MSM received HIV rapid testing kits by mail, performed the test themselves and reported the result remotely.

Results

Of the 220 men taking a home-based HIV self-testing, 33 MSM (15%) were seropositive. Nearly 65% of the men reported that they were willing to take HIV testing at CBO, while 28% preferred receiving free HIV testing in the government programs at local Centers for Disease Control and Prevention (CDC). Older and lower-income MSM, those who self-reported homosexual orientation, men with no history of sexually transmitted diseases and a lower number of sexual partners in the past six months were associated with preference for taking HIV testing at CBOs. The top three self-reported existing barriers for HIV testing were: no perception of HIV risk (56%), fear of an HIV positive result being reported to the government (41%), and fear of a positive HIV test result (36%).

Conclusion

Home-based HIV self-testing is an alternative approach for increasing the coverage of HIV testing among Chinese MSM. CBO-based HIV testing is a potential alternative, but further studies are needed to evaluate its feasibility.  相似文献   
998.
用PRV和SOM免疫荧光双标记法研究了大鼠中缝核群中SOM样神经元对咽肌前运动神经元的调控。PRV注射大鼠咽肌后,在中缝苍白核、中缝隐核、中缝大核和中缝背核中可见少量PRV和SOM双标记细胞。首次证明了大鼠中缝核群中SOM样神经元对咽肌前运动神经元的支配。推测中缝核群中的SOM可能和咽肌运动的精确调控有关。  相似文献   
999.
A marine actinomycete, designated strain BM-17, was isolated from a sediment sample collected in the Arctic Ocean. The strain was identified as Nocardia dassonvillei based on morphological, cultural, physiological, biochemical characteristics, along with the cell wall analysis and 16S rDNA gene sequence analysis. A new secondary metabolite (1), N-(2-hydroxyphenyl)-2-phenazinamine (NHP), and six known antibiotics (27) have been isolated from the saline culture broth of the stain by sequentially purification over macroporous resin D101, silica gel, Sephadex LH-20 column chromatography and preparative HPLC after the stain was incubated in soy bean media at 28 °C for 7 days. The chemical structures of the compounds were elucidated on the basis of spectroscopic analysis, including two-dimensional (2D) NMR and HR-ESI-MS data. The new compound showed significant antifungal activity against Candida albicans, with a MIC of 64 μg/ml and high cancer cell cytotoxicity against HepG2, A549, HCT-116 and COC1 cells.  相似文献   
1000.
The shell color polymorphism widely exists in economic shellfish, which not only results in a better visual perception but also shows great value as an economic trait for breeding. Small numbers of reddish-orange shell Yesso scallops, Patinopecten yessoensis, were found in cultured populations compared to the brown majority. In this study, a genome-wide association study was conducted to understand the genetic basis of shell color. Sixty-six 2b-RAD libraries with equal numbers of reddish-orange and brown shell individuals were constructed and sequenced using the Illumina HiSeq 2000 platform. A total of 322,332,684 high-quality reads were obtained, and the average sequencing depth was 18.4×. One genomic region on chromosome 11 that included 239 single-nucleotide polymorphisms (SNPs) was identified as significantly associated with shell color. After verification by high-resolution melting in another population, two SNPs were selected as specific loci for reddish-orange shell color. These two SNPs could be used to improve the selective breeding progress of true-breeding strains with complete reddish-orange scallops. In addition, within the significantly associated genomic region, candidate genes were identified using marker sequences to search the draft genome of Yesso scallop. Three genes (LDLR, FRIS, and FRIY) with known functions in carotenoid metabolism were identified. Further study using high-performance liquid chromatography proved that the relative level of carotenoids in the reddish-orange shells was 40 times higher than that in the brown shells. These results suggested that the accumulation of carotenoids contributes to the formation of reddish-orange shells.  相似文献   
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