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111.
Liu Xianchen Yang Yanyun Liu Zhen-Zhen Luo Yachen Fan Fang Jia Cun-Xian 《Sleep and biological rhythms》2019,17(3):339-348
Sleep and Biological Rhythms - Insomnia is prevalent in adolescents. Although several insomnia scales/questionnaires are available to assess insomnia symptoms and severity for adults, no insomnia... 相似文献
112.
The use of monoclonal antibodies to fragments of chicken type IV collagen in structural and localization studies 总被引:6,自引:0,他引:6
R Mayne R D Sanderson H Wiedemann J M Fitch T F Linsenmayer 《The Journal of biological chemistry》1983,258(9):5794-5797
In previous experiments, three pepsin-resistant fragments of type IV collagen were isolated from chicken gizzards and designated 7S, F3, and (F1)2F2 (Mayne, R., and Zettergren, J. G. (1980) Biochemistry 19, 4065-4072). In the present experiments, a series of monoclonal antibodies to type IV collagen were prepared, each one of which recognized an epitope present in only one of the three fragments. A high molecular weight fraction of type IV collagen (designated 7S + arms (215 nm)) was isolated after agarose gel filtration and characterized by electron microscopy after rotary shadowing and by gel electrophoresis. Analysis of 7S + arms (215 nm) by inhibition enzyme-linked immunosorbent assay demonstrated the presence of the epitopes for 7S and F3 but not for (F1)2F2. This result, therefore, provides additional evidence that the order of the pepsin-resistant fragments of chicken type IV collagen is 7S-F3-(F1)2F2. 相似文献
113.
114.
H R Habibi T A Marchant C S Nahorniak H Van der Loo R E Peter J E Rivier W W Vale 《Biology of reproduction》1989,40(6):1152-1161
The relationship between gonadotropin-releasing hormone (GnRH) receptor binding and biological activity in the goldfish pituitary for mammalian and salmon GnRH (sGnRH) analogs with structural modification at the C terminus involving replacement of glycine amide with an alkyl amine and replacement of the Gly6 residue with D amino acids was examined. The GnRH receptor binding data were analyzed with a computerized curve-fitting program (LIGAND) for a single as well as two classes of binding sites; analysis based on one site fit estimated binding affinity and capacity for one class of binding site, and analysis based on two-site fit estimated binding affinity and capacity for two classes of binding sites (high-affinity/low-capacity and low-affinity/high-capacity binding sites). The estimated receptor affinity values were then used to determine the correlation between binding affinity and gonadotropin (GTH)-release potency in vitro. The highest correlation between biological activity and receptor binding affinity was obtained for the high-affinity/low-capacity binding sites and GnRH analogs containing Trp7 and Leu8 residues (i.e., the salmon GnRH structural format) (R = 0.940 +/- 0.150). For the same group of GnRH analogs, there was no significant correlation between the relative GTH-release potency and binding affinity of the low-affinity/high-capacity sites (R = 0.159 +/- 0.434), or that obtained from a one-site fit (R = 0.198 +/- 0.431). Similarly, for mammalian GnRH analogs, significant correlation between binding affinity and biological activity (R = 0.406 +/- 0.049) was only obtained for the high-affinity sites, although the degree of correlation was significantly lower than that obtained for salmon GnRH analogs. The present findings provide strong support for the hypothesis that high-affinity GnRH receptors are involved in the control of GTH release in the goldfish pituitary. In addition, the results demonstrate clearly that the presence of Trp7, Leu8 residues in salmon GnRH molecule, a native peptide in goldfish, is important for recognition of the ligand by the GnRH receptors in the goldfish pituitary, and that structural modifications at positions 6 and 10 in this peptide can increase receptor binding affinity and biological activity at the pituitary level. The most active sGnRH analog identified to date is [D-Arg6, Pro9-NEt]-sGnRH. 相似文献
115.
Kuankuan Ai Yanli Jia Jin Li Chong Wang Yan Wang 《Journal of cellular biochemistry》2019,120(5):8069-8077
Gastric cancer (GC) is the second most common cause of cancer death worldwide but could be more curable if diagnosed at an earlier stage. At present, the capability to predict the efficaciousness of molecular diagnosis for GC for each patient remains elusive. The purpose of this study was to identify tumor biomarkers through systems analysis of multigene predictors exploiting the available data resource. In this study, we investigated the top 10% overexpressed genes in GC from five data sets of the Oncomine platform, with 265 GC samples versus 174 normal gastric mucosa samples. Sixteen candidate genes were identified as predictors of GC, of which 14 genes were verified through the comparison of expression levels in specimens from normal (chronic gastritis, 21 samples) and GC groups (38 samples). In addition, unique molecular portraits of diffuse adenocarcinoma (DA), intestinal adenocarcinoma (IA), and mixed adenocarcinoma (MA) were studied through Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis, where DA showed higher extracellular matrix alteration while IA and MA showed higher cell-cycle alteration than other types. We also found that the elevated expressions of genes during GC progression were independent of gene mutations, and high core-binding factor subunit β expression is correlated with a high overall survival rate in GC patients. Our research may provide an efficient clinical diagnosis of GC at an early stage with high accuracy and thus help improve the overall survival rate through early therapeutic interventions. 相似文献
116.
Identification,Design and Bio-Evaluation of Novel Hsp90 Inhibitors by Ligand-Based Virtual Screening
JianMin Jia XiaoLi Xu Fang Liu XiaoKe Guo MingYe Zhang MengChen Lu LiLi Xu JinLian Wei Jia Zhu ShengLie Zhang ShengMiao Zhang HaoPeng Sun QiDong You 《PloS one》2013,8(4)
Heat shock protein 90 (Hsp90), whose inhibitors have shown promising activity in clinical trials, is an attractive anticancer target. In this work, we first explored the significant pharmacophore features needed for Hsp90 inhibitors by generating a 3D-QSAR pharmacophore model. It was then used to virtually screen the SPECS databases, identifying 17 hits. Compound S1 and S13 exhibited the most potent inhibitory activity against Hsp90, with IC50 value 1.61±0.28 μM and 2.83±0.67 μM, respectively. Binding patterns analysis of the two compounds with Hsp90 revealed reasonable interaction modes. Further evaluation showed that the compounds exhibited good anti-proliferative effects against a series of cancer cell lines with high expression level of Hsp90. Meanwhile, S13 induced cell apoptosis in a dose-dependent manner in different cell lines. Based on the consideration of binding affinities, physicochemical properties and toxicities, 24 derivatives of S13 were designed, leading to the more promising compound S40, which deserves further optimization. 相似文献
117.
118.
Taxonomy and phylogeny of Ceriporia (Polyporales,Basidiomycota) with an emphasis of Chinese collections 总被引:1,自引:0,他引:1
Bi-Si Jia Li-Wei Zhou Bao-Kai Cui Bernard Rivoire Yu-Cheng Dai 《Mycological Progress》2014,13(1):81-93
Ceriporia accommodates a kind of wood-inhabiting polypores producing resupinate basidiocarps and causing a white rot. More than 30 species of this genus have been described; however, only a few species were referred to molecular phylogeny. In this study, a total of 203 specimens of Ceriporia were studied morphologically, and the ITS and/or nLSU regions from 42 samples, representing 18 species, were sequenced for phylogenetic analysis. Based on both morphological and phylogenetic analyses, three new species of Ceriporia, C. bubalinomarginata, C. pseudocystidiata and C. variegata, are described and illustrated. An annotated identification key is provided for all 20 species of this genus thus far known in China. Our phylogeny shows that (1) Ceriporia is not monophyletic, (2) C. spissa and C. viridans as morphologically circumscribed are polyphyletic, (3) C. inflata is retained for both C. inflata and C. jiangxiensis, and (4) presence or absence of hymenial cystidia is not a useful character in delimiting species relationships in Ceriporia. 相似文献
119.
120.
Zhihui Feng Zhongbo Liu Xuesen Li Haiqun Jia Lijuan Sun Chuan Tian Lihong Jia Jiankang Liu 《The Journal of nutritional biochemistry》2010,21(12):1222-1231
Vitamin E has long been identified as a major lipid-soluble chain-breaking antioxidant in mammals. α-Tocopherol is a vitamin E component and the major form in the human body. We propose that, besides its direct chain-breaking antioxidant activity, α-tocopherol may exert an indirect antioxidant activity by enhancing the cell's antioxidant system as a Phase II enzyme inducer. We investigated α-tocopherol's inducing effect on Phase II enzymes and its protective effect on acrolein-induced toxicity in a human retinal pigment epithelial (RPE) cell line, ARPE-19. Acrolein, a major component of cigarette smoke and also a product of lipid peroxidation, at 75 μmol/L over 24 h, caused significant loss of ARPE-19 cell viability, increased oxidative damage, decreased antioxidant defense, inactivation of the Keap1/Nrf2 pathway, and mitochondrial dysfunction. ARPE-19 cells have been used as a model of smoking- and age-related macular degeneration. Pretreatment with α-tocopherol activated the Keap1/Nrf2 pathway by increasing Nrf2 expression and inducing its translocation to the nucleus. Consequently, the expression and/or activity of the following Phase II enzymes increased: glutamate cysteine ligase, NAD(P)H:quinone oxidoreductase 1, heme-oxygenase 1, glutathione S-transferase and superoxide dismutase; total antioxidant capacity and glutathione also increased. This antioxidant defense enhancement protected ARPE-19 cells from an acrolein-induced decrease in cell viability, lowered reactive oxygen species and protein oxidation levels, and improved mitochondrial function. These results suggest that α-tocopherol protects ARPE-19 cells from acrolein-induced cellular toxicity, not only as a chain-breaking antioxidant, but also as a Phase II enzyme inducer. 相似文献