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91.
92.
Identification and Characterization of a Constitutively Active STAT5 Mutant That Promotes Cell Proliferation 总被引:26,自引:2,他引:24
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Hiroko Yamada Kazuaki Takahashi Olline Lim Somana Svay Channarena Chuon Sirany Hok Son Huy Do Mayumi Fujimoto Tomoyuki Akita Noboru Goto Keiko Katayama Masahiro Arai Junko Tanaka 《PloS one》2015,10(8)
Hepatitis E virus (HEV) is a growing public health problem in many countries. In this study, we investigated HEV seroprevalence among the general population in the Siem Reap province, Cambodia, and performed HEV genetic analysis with the aim to develop an HEV prevention strategy. This seroepidemiological cross-sectional study conducted from 2010 to 2014 included 868 participants from four different locations in Siem Reap province, Cambodia. They answered questionnaires and provided blood samples for the analysis of hepatitis virus infections. Among the participants (360 men and 508 women; age range, 7–90 years), the prevalence of anti-HEV IgG was 18.4% (95% confidence interval: 15.9–21.0); HEV RNA was detected in two participants (0.23%) and was classified as genotype 3 and 4. Full-length genome of the genotype 4 isolate, CVS-Sie10, was sequenced; it contained 7,222 nucleotides and three ORFs and demonstrated high sequence identity with the swine China isolates swGX40 (95.57%), SS19 (94.37%), and swDQ (91.94%). Multivariate logistic regression analysis revealed that men, elderly people, and house workers were risk groups significantly associated with the positivity for anti-HEV IgG. This is the first report on the detection of HEV genotype 4 in humans in Cambodia and on the complete genome sequence of HEV genotype 4 from this country. Our study demonstrates that new HEV infection cases occur frequently among the general population in Cambodia, and effective preventive measures are required. 相似文献
95.
Kanae Tashiro Mayumi Shishido Keiko Fujimoto Yuko Hirota Kazuyuki Yo Takamasa Gomi Yoshitaka Tanaka 《Biochemical and biophysical research communications》2014
Autophagy is an intracellular degradative system that is believed to be involved in the aging process. The contribution of autophagy to age-related changes in the human skin is unclear. In this study, we examined the relationship between autophagy and skin aging. Transmission electron microscopy and immunofluorescence microscopy analyses of skin tissue and cultured dermal fibroblasts derived from women of different ages revealed an increase in the number of nascent double-membrane autophagosomes with age. Western blot analysis showed that the amount of LC3-II, a form associated with autophagic vacuolar membranes, was significantly increased in aged dermal fibroblasts compared with that in young dermal fibroblasts. Aged dermal fibroblasts were minimally affected by inhibition of autophagic activity. Although lipofuscin autofluorescence was elevated in aged dermal fibroblasts, the expression of Beclin-1 and Atg5—genes essential for autophagosome formation—was similar between young and aged dermal fibroblasts, suggesting that the increase of autophagosomes in aged dermal fibroblasts was due to impaired autophagic flux rather than an increase in autophagosome formation. Treatment of young dermal fibroblasts with lysosomal protease inhibitors, which mimic the condition of aged dermal fibroblasts with reduced autophagic activity, altered the fibroblast content of type I procollagen, hyaluronan and elastin, and caused a breakdown of collagen fibrils. Collectively, these findings suggest that the autophagy pathway is impaired in aged dermal fibroblasts, which leads to deterioration of dermal integrity and skin fragility. 相似文献
96.
Alimjan Idiris Hideki Tohda Mayumi Sasaki Katsunori Okada Hiromichi Kumagai Yuko Giga-Hama Kaoru Takegawa 《Applied microbiology and biotechnology》2010,85(3):667-677
Previously, we achieved approximately 30-fold enhanced secretion of the protease-sensitive model protein human growth hormone
(hGH) by multiple gene deletion of seven obstructive proteases in the fission yeast Schizosaccharomyces pombe. However, intracellular retention of secretory hGH was found in the resultant multiprotease-deficient strains. As a solution,
genetic modification of the intracellular trafficking pathway that is related to intracellular retention of hGH was attempted
on a protease octuple deletant strain. Vacuolar accumulation of the intracellularly retained hGH was identified by secretory
expression of hGH fused with EGFP, and three vacuolar protein sorting (vps)-deficient strains, vps10Δ, vps22Δ, and vps34Δ, were determined on account of their hGH secretion efficiency. The mutant vps10Δ was found to be effective for hGH secretion, which suggested a role for vps10 in the vacuolar accumulation of the intracellularly retained hGH. Finally, vps10 deletion was performed on the protease octuple deletant strain, which led to an approximately 2-fold increase in hGH secretion.
This indicated the possible application of secretory-pathway modification and multiple protease deletion for improving heterologous
protein secretion from the fission yeast S. pombe. 相似文献
97.
Okabe T Yamazaki Y Shiotani M Suzuki T Shiohara M Kasuga E Notake S Yanagisawa H 《Microbiological research》2010,165(1):11-20
Haemophilus influenzae is a common pathogen of respiratory infections. We examined whether beta-lactamase-negative ampicillin-resistant (BLNAR) strains that are known to have ampicillin resistance due to a substitution of amino acid of penicillin binding protein (PBP)-3, differ from beta-lactamase-negative ampicillin-susceptible strains with regard to invasion of bronchial epithelium. After 3h incubation of each of 34 beta-lactamase-negative ampicillin-susceptible and 57 BLNAR strains in the presence of BEAS-2B cells, a human bronchial epithelium cell line, extracellular bacteria were killed using gentamicin and intracellular bacteria numbered. All nine strains in which the efficiency of invasion was 1% or higher were BLNAR strains. The rate of invasion was significantly greater in strains with PBP-3 amino acid substitution (Met377 to Ile, Ser385 to Thr, Leu389 to Phe, and Asn526 to Lys) (n=34) than in those with no amino acid substitution. Electron microscopy showed that high invasive BLNAR strains were observed in cytoplasm of BEAS-2B cell layer. The injured cells were 9.44+/-1.76% among attaching cells examined by trypan blue staining after 6h. These data may suggest that the amino acid substitution of the PBP in BLNAR strains may at least partly play roles in macropinocytosis, leading to the invasion and injury to epithelial cells. 相似文献
98.
Pyrrole derivatives as potent inhibitors of lymphocyte-specific kinase: Structure,synthesis, and SAR
Tetsuo Takayama Hiroki Umemiya Hideaki Amada Tetsuya Yabuuchi Fumiyasu Shiozawa Hironori Katakai Akiko Takaoka Akie Yamaguchi Mayumi Endo Masakazu Sato 《Bioorganic & medicinal chemistry letters》2010,20(1):108-111
We have described the synthesis, enzyme inhibitory activity, structure–activity relationships, and proposed binding mode of a novel series of pyrrole derivatives as lymphocyte-specific kinase (Lck) inhibitors. The most potent analogs exhibited good enzyme inhibitory activity (IC50s <10 nM) for Lck kinase inhibition. 相似文献
99.
Shunsuke Ohashi Tatsuya Iemura Naoki Okada Shingo Itoh Hayato Furukawa Masaaki Okuda Mayumi Ohnishi-Kameyama Takuro Ogawa Hideaki Miyashita Tadashi Watanabe Shigeru Itoh Hirozo Oh-oka Kazuhito Inoue Masami Kobayashi 《Photosynthesis research》2010,104(2-3):305-319
Minor but key chlorophylls (Chls) and quinones in photosystem (PS) I-type reaction centers (RCs) are overviewed in regard to their molecular structures. In the PS I-type RCs, the prime-type chlorophylls, namely, bacteriochlorophyll (BChl) a′ in green sulfur bacteria, BChl g′ in heliobacteria, Chl a′ in Chl a-type PS I, and Chl d′ in Chl d-type PS I, function as the special pairs, either as homodimers, (BChl a′)2 and (BChl g′)2 in anoxygenic organisms, or heterodimers, Chl a/a′ and Chl d/d′ in oxygenic photosynthesis. Conversions of BChl g to Chl a and Chl a to Chl d take place spontaneously under mild condition in vitro. The primary electron acceptors, A 0, are Chl a-derivatives even in anoxygenic PS I-type RCs. The secondary electron acceptors are naphthoquinones, whereas the side chains may have been modified after the birth of cyanobacteria, leading to succession from menaquinone to phylloquinone in oxygenic PS I. 相似文献
100.