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201.
202.
Obesity can be associated with systemic low-grade inflammation that contributes to obesity-related metabolic disorders. Recent studies raise the possibility that hypothalamic inflammation contributes to the pathogenesis of diet-induced obesity (DIO), while another study reported that obesity decreases the expression of pro-inflammatory cytokines in spleen. The following study examines the hypothesis that obesity suppresses the splenic synthesis of the anti-inflammatory cytokine, interleukin (IL)-10, thereby resulting in chronic hypothalamic inflammation. The results showed that due to oxidative stress or apoptosis, the synthesis of splenic IL-10 was decreased in DIO when compared with non-obesity rats. Splenectomy (SPX) accelerated DIO-induced inflammatory responses in the hypothalamus. Interestingly, SPX suppressed the DIO-induced increases in food intake and body weight and led to a hypothalamic pro-inflammatory state that was similar to that produced by DIO, indicating that hypothalamic inflammation exerts a dual effect on energy metabolism. These SPX-induced changes were inhibited by the systemic administration of IL-10. Moreover, SPX had no effect on hypothalamic inflammatory responses in IL-10-deficient mice. These data suggest that spleen-derived IL-10 plays an important role in the prevention of hypothalamic inflammation and may be a therapeutic target for the treatment of obesity and hypothalamic inflammation.  相似文献   
203.
The factors responsible for conferring germline competence in embryonic stem (ES) cell lines remain unidentified. In the present study, rat ES cell lines (n = 17) were established with 3i medium (SU5402, PD0325901, CHIR99021), 2i medium (PD0325901, CHIR99021) or 2iF medium (PD0325901, CHIR99021, forskolin), and their potential for germline transmission to the G1 generation was examined. Rat strains were divided into an albino group (F344, Wistar or CAG/Venus transgenic rats with the Wistar background) or a colored coat group (Brown-Norway, Dark-Agouti, or BLK rats selected from >F3 generations of Wistar × Dark-Agouti rats based on their black coat color). Successful germline transmission was observed in 57 % (4/7), 40 % (2/5) and 100 % (5/5) of the ES cells established with 3i, 2i and 2iF media, respectively. ES cell lines from the homozygous CAG/Venus transgenic rats were established in all three media, but only the lines established with the 2iF medium were germline-competent. Neither coat-color (albino: 64 %, 7/11; colored: 67 %, 4/6) nor gender of the ES cell lines (XX: 67 %, 2/3; XY: 64 %, 9/14) were likely to affect germline transmission.  相似文献   
204.
An improved fluorometric HPLC method for sialic acid determination was developed by employing synthetic N-propionylneuraminic acid (NPNA) as an internal standard. A fixed amount of NPNA was added to a sialoglycoconjugate sample. After hydrolyzing sialioglycoconjugates with diluted sulfuric acid, the released sialic acids and NPNA were derivatized with a fluorogenic compound, 1,2-diamino-4,5-(methylenedioxy)benzene (DMB), followed by fluorometric HPLC. The fluorescent derivative of NPNA was separated from those of N-acetylneuraminic acid, N-glycolylneuraminic acid, 2-keto-3-deoxy-D-glycero-D-galacto-nonoic acid, and 2-keto-3-deoxyoctanoate on HPLC. The separation of NPNA derivative on HPLC was not interfered by components of biological samples such as human sera. Using this internal standard method, low amounts of NANA (0.15-1.0 ng) were quantified with the coefficient of variation values below 4%. Using this method, the sialic acid content of human apolipoprotein E was successfully determined. The present method is useful for sensitive and accurate quantification of sialic acids of different molecular species in biological samples.  相似文献   
205.
We recently identified a novel cDNA encoding a small secretory protein of 80 amino acid residues, termed neurosecretory protein GL (NPGL), from the chicken hypothalamus. Homologs of NPGL have been reported to be present in mammals, such as human and rat. NPGL is amidated at its C‐terminus, contains an intramolecular disulfide bond, and is hydrophobic in nature. In this study, we have optimized the synthesis of the entire 80‐amino acid peptide sequence of rat NPGL by microwave‐assisted solid‐phase peptide synthesis. NPGL was obtained with a 10% yield when the coupling reactions were performed using 1‐[Bis(dimethylamino)methylene]‐1H‐1,2,3‐triazolo[4,5‐b]pyridinium‐3‐oxid hexafluorophosphate (HATU) at 50 °C for 5 min, and Fmoc deprotections were performed using 40% piperidine containing 0.1 M HOBt. Furthermore, the disulfide bond of NPGL was formed with 20% yield with the use of glutathione‐containing redox buffer and 50% acetonitrile. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.  相似文献   
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207.
Abstract The complete nucleotide sequence of pNS1 (3879 bp), a tetracycline-resistance (TcR) plasmid drived from staphylococcal plasmid pTP5, has been determined and compared with that of the staphylococcal TcR plasmid pT181 [6]. The nucleotide sequences of the 2 plasmids are in agreement, except for 18 nucleotides, but these differences are significant in that they give rise to new open reading frames (ORFs). A short ORF-D is found in the copy control region, and the TcR region contains a single large ORF-A, that encodes the Tet protein (50 kDa). The upstream region of ORF-A contains 3 inverted repeat sequences, which can generate structures very similar in conformation of the structure of the control region of the inducible erythromycin-resistance gene of pE194.  相似文献   
208.
209.
The proteasome subunit beta type 8 (PSMB8) gene encodes a catalytic subunit of immunoproteasome that plays a central role in the processing of antigenic peptides presented by major histocompatibility complex class I molecules. The A- and F-type alleles defined by the 31st amino acid residue determining cleaving specificity have been identified from ray-finned fish, amphibia, and reptiles. These two types show extremely long-term trans-species polymorphism in Polypteriformes, Cypriniformes, and Salmoniformes, suggesting the presence of very ancient lineages termed A and F. To elucidate the evolution of the PSMB8 dimorphism in basal ray-finned fish, we analyzed Pantodon buchholzi (Osteoglossiformes), seven species of Anguilliformes, and Hypomesus nipponensis (Osmeriformes). Both A and F lineage sequences were identified from P. buchholzi and H. nipponensis, confirming that these two lineages have been conserved by basal ray-finned fish. However, both the A- and F-type alleles found in Anguilliformes species belonged to the F lineage irrespective of their types. This apparently suggests that the A lineage was lost in the common ancestor of Anguilliformes, and recovery of the A type within the F lineage occurred in Anguilliformes. The apparent loss of the F lineage and recovery of the F type within the A lineage have already been reported from tetrapods and higher teleosts. However, this is the first report on the reverse situation and reveals the dynamic evolution of the PSMB8 dimorphism.  相似文献   
210.
The mutagenicities of naturally occurring xanthones were tested in Salmonella typhimurium TA100, TA98, TA97, and TA2637 by the preincubation method. Xanthydrol, gentisein, gentisin, isogentisin, 1-hydroxy-3,7-dimethoxyxanthone, 1,3,7,-trimethoxyxanthone, desmethylbellidifolin, bellidifolin and dimethylbellidifolin were mutagenic, but unsubstituted xanthone was not mutagenic to TA100, TA98, TA97 and TA2637 with or without a metabolic activation system. The β-O-glucosides, norswertianolin and swertianolin, were only mutagenic when a metabolic activation system containing β-glucosidase was used, and the C-glucoside mangiferin was not mutagenic even with this system.  相似文献   
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