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941.
Jing Lu Shengchang Xin Huan Meng Matt Veldman David Schoenfeld Chao Che Ruibin Yan Hanbing Zhong Song Li Shuo Lin 《PloS one》2013,8(4)
Polo-like kinase 1 (PLK1), one of the key regulators of mitosis, is a target for cancer therapy due to its abnormally high activity in several tumors. Plk1 is highly conserved and shares a nearly identical 3-D structure between zebrafish and humans. The initial 10 mitoses of zebrafish embryonic cleavages occur every∼30 minutes, and therefore provide a rapid assay to evaluate mitosis inhibitors including those targeting Plk1. To increase efficiency and specificity, we first performed a computational virtual screen of∼60000 compounds against the human Plk1 3-D structure docked to both its kinase and Polo box domain. 370 candidates with the top free-energy scores were subjected to zebrafish assay and 3 were shown to inhibit cell division. Compared to general screen for compounds inhibiting zebrafish embryonic cleavage, computation increased the efficiency by 11 folds. One of the 3 compounds, named I2, was further demonstrated to effectively inhibit multiple tumor cell proliferation in vitro and PC3 prostate cancer growth in Xenograft mouse model in vivo. Furthermore, I2 inhibited Plk1 enzyme activity in a dose dependent manner. The IC50 values of I2 in these assays are compatible to those of ON-01910, a Plk1 inhibitor currently in Phase III clinic trials. Our studies demonstrate that zebrafish assays coupled with computational screening significantly improves the efficiency of identifying specific regulators of biological targets. The PLK1 inhibitor I2, and its analogs, may have potential in cancer therapeutics. 相似文献
942.
Yi-Hsuan Lin Yi-Chun Chen Yen-Han Tseng Ming-Hwai Lin Shinn-Jang Hwang Tzeng-Ji Chen Li-Fang Chou 《PloS one》2013,8(4)
Aims
The palliative care has spread rapidly worldwide in the recent two decades. The development of hospice services in rural areas usually lags behind that in urban areas. The aim of our study was to investigate whether the urban-rural disparity widens in a country with a hospital-based hospice system.Methods
From the nationwide claims database within the National Health Insurance in Taiwan, admissions to hospices from 2000 to 2006 were identified. Hospices and patients in each year were analyzed according to geographic location and residence.Results
A total of 26,292 cancer patients had been admitted to hospices. The proportion of rural patients to all patients increased with time from 17.8% in 2000 to 25.7% in 2006. Although the numbers of beds and the utilizations in both urban and rural hospices expanded rapidly, the increasing trend in rural areas was more marked than that in urban areas. However, still two-thirds (898/1,357) of rural patients were admitted to urban hospices in 2006.Conclusions
The gap of hospice utilizations between urban and rural areas in Taiwan did not widen with time. There was room for improvement in sufficient supply of rural hospices or efficient referral of rural patients. 相似文献943.
Zhen-Zhu Su Li-Juan Mao Na Li Xiao-Xiao Feng Zhi-Lin Yuan Li-Wei Wang Fu-Cheng Lin Chu-Long Zhang 《PloS one》2013,8(4)
The mutualism pattern of the dark septate endophyte (DSE) Harpophora oryzae in rice roots and its biocontrol potential in rice blast disease caused by Magnaporthe oryzae were investigated. Fluorescent protein-expressing H. oryzae was used to monitor the colonization pattern. Hyphae invaded from the epidermis to the inner cortex, but not into the root stele. Fungal colonization increased with root tissue maturation, showing no colonization in the meristematic zone, slight colonization in the elongation zone, and heavy colonization in the differentiation zone. H. oryzae adopted a biotrophic lifestyle in roots accompanied by programmed cell death. Real-time PCR facilitated the accurate quantification of fungal growth and the respective plant response. The biocontrol potential of H. oryzae was visualized by inoculation with eGFP-tagged M. oryzae in rice. H. oryzae protected rice from M. oryzae root invasion by the accumulation of H2O2 and elevated antioxidative capacity. H. oryzae also induced systemic resistance against rice blast. This systemic resistance was mediated by the OsWRKY45-dependent salicylic acid (SA) signaling pathway, as indicated by the strongly upregulated expression of OsWRKY45. The colonization pattern of H. oryzae was consistent with the typical characteristics of DSEs. H. oryzae enhanced local resistance by reactive oxygen species (ROS) and high antioxidative level and induced OsWRKY45-dependent SA-mediated systemic resistance against rice blast. 相似文献
944.
945.
946.
I-Cheng Lee Chen-Hao Lin Yi-Hsiang Huang Teh-Ia Huo Chien-Wei Su Ming-Chih Hou Hui-Chun Huang Kuei-Chuan Lee Che-Chang Chan Ming-Wei Lin Han-Chieh Lin Shou-Dong Lee 《PloS one》2013,8(2)
Background & Aims
The clinical relevance of single nucleotide polymorphisms (SNPs) near the IL28B gene is controversial in patients with hepatitis B virus (HBV) infection. This study aimed to investigate the role of viral and host factors, including IL28B genotypes, in the natural course of chronic hepatitis B (CHB).Methods
The study enrolled consecutive 115 treatment-naive CHB patients. HBV viral loads, genotypes, precore and basal core promotor mutations, serum hepatitis B surface antigen (HBsAg) and interferon-gamma inducible protein 10 (IP-10) levels as well as four SNPs of IL28B were determined. Serial alanine transaminase (ALT) levels in the previous one year before enrollment at an interval of three months were recorded. Factors associated with active hepatitis, defined as persistent ALT >2× upper limit of normal (ULN) or a peak ALT level >5× ULN, were evaluated.Results
The prevalence of rs8105790 TT, rs12979860 CC, rs8099917 TT, and rs10853728 CC genotypes were 88.3%, 87.4%, 88.4% and 70.9%, respectively. In HBeAg-positive patients (n = 48), HBV viral load correlated with active hepatitis, while in HBeAg-negative patients (n = 67), rs10853728 CC genotype (p = 0.032) and a trend of higher IP-10 levels (p = 0.092) were associated with active hepatitis. In multivariate analysis, high viral load (HBV DNA >108 IU/mL, p = 0.042, odds ratio = 3.946) was significantly associated with HBeAg-positive hepatitis, whereas rs10853728 CC genotype (p = 0.019, odds ratio = 3.927) was the only independent factor associated with active hepatitis in HBeAg-negative population.Conclusions
HBV viral load and IL28B rs10853728 CC genotype correlated with hepatitis activity in HBeAg-positive and HBeAg-negative CHB, respectively. Both viral and host factors play roles in disease activity during different phases of CHB. 相似文献947.
Yike Yuan Yuwei Zhao Shengchang Xin Ni Wu Jiaolin Wen Song Li Lijuan Chen Yuquan Wei Hanshuo Yang Shuo Lin 《PloS one》2013,8(4)
The Hedgehog (Hh) pathway inhibitors have shown great promise in cancer therapeutics. SANT75, a novel compound we previously designed to specially inhibit the Smoothened (SMO) protein in the Hh pathway, has greater inhibitory potency than many of commonly used Hh inhibitors. However, preclinical studies of SANT75 revealed water insolubility and acute toxicity. To overcome these limitations, we developed a liposomal formulation of SANT75 and investigated its antitumor efficacy in vitro and in vivo. We encapsulated SANT75 into PEGylated liposome and the mean particle size distribution and zeta-potential (ZP) of liposomes were optimized. Using the Shh-light2 cell and Gli-GFP or Flk-GFP transgenic reporter zebrafish, we confirmed that liposome-encapsulated SANT75 inhibited Hh activity with similar potency as the original SANT75. SANT75 encapsulated into liposome exerted strong tumor growth-inhibiting effects in vitro and in vivo. In addition, the liposomal SANT75 therapy efficiently improved the survival time of tumor-bearing mice without obvious systemic toxicity. The pathological morphology and immunohistochemistry staining revealed that liposomal SANT75 induced tumor cell apoptosis, inhibited tumor angiogenesis as assessed by CD31 and down-regulated the expression of Hh target protein Gli-1 in tumor tissues. Our findings suggest that liposomal formulated SANT75 has improved solubility and bioavailability and should be further developed as a drug candidate for treating tumors with abnormally high Hh activity. 相似文献
948.
Jiaojiao Chu Hangxiang Zhang Xiuqing Huang Yajun Lin Tao Shen Beidong Chen Yong Man Shu Wang Jian Li 《PloS one》2013,8(2)
Apelin, a novel adipokine, is the specific endogenous ligand of G protein-coupled receptor APJ. Consistent with its putative role as an adipokine, apelin has been linked to states of insulin resistance. However, the function of apelin in hepatic insulin resistance, a vital part of insulin resistance, and its underlying mechanisms still remains unclear. Here we define the impacts of apelin on TNF-α-induced reduction of glycogen synthesis in the hepatocytes. Our studies indicate that apelin reversed TNF-α-induced reduction of glycogen synthesis in HepG2 cells, mouse primary hepatocytes and liver tissues of C57BL/6J mice by improving JNK-IRS1-AKT-GSK pathway. Moreover, Western blot revealed that APJ, but not apelin, expressed in the hepatocytes and liver tissues of mice. We found that F13A, a competitive antagonist for G protein-coupled receptor APJ, suppressed the effects of apelin on TNF-α-induced reduction of glycogen synthesis in the hepatocytes, suggesting APJ is involved in the function of apelin. In conclusion, we show novel evidence suggesting that apelin ameliorates TNF-α-induced reduction of glycogen synthesis in the hepatocytes through G protein-coupled receptor APJ. Apelin appears as a beneficial adipokine with anti-insulin resistance properties, and thus as a promising therapeutic target in metabolic disorders. 相似文献
949.
Guo-Xin Hu Han Lin Qing-Quan Lian Shu-Hua Zhou Jingjing Guo Hong-Yu Zhou Yanhui Chu Ren-Shan Ge 《PloS one》2013,8(3)
Background
11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) activates glucocorticoid locally in liver and fat tissues to aggravate metabolic syndrome. 11β-HSD1 selective inhibitor can be used to treat metabolic syndrome. Curcumin and its derivatives as selective inhibitors of 11β-HSD1 have not been reported.Methodology
Curcumin and its 12 derivatives were tested for their potencies of inhibitory effects on human and rat 11β-HSD1 with selectivity against 11β-HSD2. 200 mg/kg curcumin was gavaged to adult male Sprague-Dawley rats with high-fat-diet-induced metabolic syndrome for 2 months.Results and Conclusions
Curcumin exhibited inhibitory potency against human and rat 11β-HSD1 in intact cells with IC50 values of 2.29 and 5.79 µM, respectively, with selectivity against 11β-HSD2 (IC50, 14.56 and 11.92 µM). Curcumin was a competitive inhibitor of human and rat 11β-HSD1. Curcumin reduced serum glucose, cholesterol, triglyceride, low density lipoprotein levels in high-fat-diet-induced obese rats. Four curcumin derivatives had much higher potencies for Inhibition of 11β-HSD1. One of them is (1E,4E)-1,5-bis(thiophen-2-yl) penta-1,4-dien-3-one (compound 6), which had IC50 values of 93 and 184 nM for human and rat 11β-HSD1, respectively. Compound 6 did not inhibit human and rat kidney 11β-HSD2 at 100 µM. In conclusion, curcumin is effective for the treatment of metabolic syndrome and four novel curcumin derivatives had high potencies for inhibition of human 11β-HSD1 with selectivity against 11β-HSD2. 相似文献950.
Kuo-Lun Huang Kun-Ju Lin Ing-Tsung Hsiao Hung-Chou Kuo Wen-Chuin Hsu Wen-Li Chuang Mei-Ping Kung Shiaw-Pyng Wey Chia-Ju Hsieh Yau-Yau Wai Tzu-Chen Yen Chin-Chang Huang 《PloS one》2013,8(3)