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991.
HM Manir Ahmed Jan-Ying Yeh Yi-Chia Tang Winston Teng-Kuei Cheng Bor-Rung Ou 《Journal of biosciences》2014,39(3):453-461
Estrogen and progestins have adverse effects, and many of these adverse effects are caused by progestins. Due to this, many women choose to use botanical alternatives for hormone replacement therapy, which does not trigger steroidogenic properties. Therefore, it is necessary to screen these herbs for progestogenic and anti-progestogenic properties. Extract of 13 Chinese medicinal plants were analysed for progestogenic and anti-progestogenic activities by using progesterone response element-driven luciferase reporter gene bioassay. MTT assay was carried out to investigate the cytotoxic effect of herb extract on PAE cells. Among the 13 herbs, Dipsacus asperoides extract exhibited progestogenic activity, and 10 species – Cortex eucommiae, Folium artemisiae argyi, Glycyrrhiza uralensis, Angelica sinensis, Atractylodes macrocephala koidz, Scutellaria baicalensis, Cuscuta chinensis, Euscaphis japonica, Ailanthus altissima, and Dioscorea opposita – were recognized to have anti-progestogenic like activities. Extract of Dipsacus asperoides demonstrated dose-dependent progestogenic activity, and the progestogenic activity of 100 μg/mL extracts was equivalent to 31.45 ng/mL progesterone activity. Herbs extracts that exhibited anti-progestogenic-like activity also inhibited the 314.46 ng/mL progesterone activity in a dose-response manner. None of the herb extracts shown significant toxic effect on PAE cells at 40–100 μg/mL compared to control. This discovery will aid selection of suitable herbs for hormone replacement therapy. 相似文献
992.
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994.
Transgenic rice endosperm as a bioreactor for molecular pharming 总被引:1,自引:0,他引:1
Jiquan Ou Zhibin Guo Jingni Shi Xianghong Wang Jingru Liu Bo Shi Fengli Guo Chufu Zhang Daichnag Yang 《Plant cell reports》2014,33(4):585-594
Plants provide a promising expression platform for producing recombinant proteins with several advantages in terms of high expression level, lower production cost, scalability, and safety and environment-friendly. Molecular pharming has been recognized as an emerging industry with strategic importance that could play an important role in economic development and healthcare in China. Here, this review represents the significant advances using transgenic rice endosperm as bioreactor to produce various therapeutic recombinant proteins in transgenic rice endosperm and large-scale production of OsrHSA, and discusses the challenges to develop molecular pharming as an emerging industry with strategic importance in China. 相似文献
995.
Asymmetric Addition of Triethylaluminium to Aromatic Aldehydes Catalyzed by Titanium‐(5,5’‐Biquinoline‐6,6’‐Diol) Complexes 下载免费PDF全文
Qian Chen Jun Ou Guo‐Shu Chen Tian‐Hui Liu Bin Xie Hai‐Bo Liang Li‐Qiong Xie Yi‐Xin Chen 《Chirality》2014,26(5):268-271
A novel convenient procedure for the resolution of 5,5’‐biquinoline‐6,6’‐diol (BIQOL) was achieved by separating the corresponding diastereomeric mixture of (S)‐(+)‐camphorsulfonates on a semiprepared XDB‐C8 column followed by hydrolysis. The efficient asymmetric addition of triethylaluminium to aromatic aldehydes catalyzed by Ti‐(+)/(–)BIQOL complexes under mild conditions is described. The reactions led to the formation of 1‐arylpropan‐1‐ol in up to 87.5% ee. Chirality 26:268‐271, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
996.
Raquel González Ghyslain Mombo-Ngoma Sma?la Ouédraogo Mwaka A. Kakolwa Salim Abdulla Manfred Accrombessi John J. Aponte Daisy Akerey-Diop Arti Basra Valérie Briand Meskure Capan Michel Cot Abdunoor M. Kabanywanyi Christian Kleine Peter G. Kremsner Eusebio Macete Jean-Rodolphe Mackanga Achille Massougbodgi Alfredo Mayor Arsenio Nhacolo Golbahar Pahlavan Michael Ramharter María Rupérez Esperan?a Sevene Anifa Vala Rella Zoleko-Manego Clara Menéndez 《PLoS medicine》2014,11(9)
Background
Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended by WHO to prevent malaria in African pregnant women. The spread of SP parasite resistance has raised concerns regarding long-term use for IPT. Mefloquine (MQ) is the most promising of available alternatives to SP based on safety profile, long half-life, and high efficacy in Africa. We evaluated the safety and efficacy of MQ for IPTp compared to those of SP in HIV-negative women.Methods and Findings
A total of 4,749 pregnant women were enrolled in an open-label randomized clinical trial conducted in Benin, Gabon, Mozambique, and Tanzania comparing two-dose MQ or SP for IPTp and MQ tolerability of two different regimens. The study arms were: (1) SP, (2) single dose MQ (15 mg/kg), and (3) split-dose MQ in the context of long lasting insecticide treated nets. There was no difference on low birth weight prevalence (primary study outcome) between groups (360/2,778 [13.0%]) for MQ group and 177/1,398 (12.7%) for SP group; risk ratio [RR], 1.02 (95% CI 0.86–1.22; p = 0.80 in the ITT analysis). Women receiving MQ had reduced risks of parasitemia (63/1,372 [4.6%] in the SP group and 88/2,737 [3.2%] in the MQ group; RR, 0.70 [95% CI 0.51–0.96]; p = 0.03) and anemia at delivery (609/1,380 [44.1%] in the SP group and 1,110/2743 [40.5%] in the MQ group; RR, 0.92 [95% CI 0.85–0.99]; p = 0.03), and reduced incidence of clinical malaria (96/551.8 malaria episodes person/year [PYAR] in the SP group and 130/1,103.2 episodes PYAR in the MQ group; RR, 0.67 [95% CI 0.52–0.88]; p = 0.004) and all-cause outpatient attendances during pregnancy (850/557.8 outpatients visits PYAR in the SP group and 1,480/1,110.1 visits PYAR in the MQ group; RR, 0.86 [0.78–0.95]; p = 0.003). There were no differences in the prevalence of placental infection and adverse pregnancy outcomes between groups. Tolerability was poorer in the two MQ groups compared to SP. The most frequently reported related adverse events were dizziness (ranging from 33.9% to 35.5% after dose 1; and 16.0% to 20.8% after dose 2) and vomiting (30.2% to 31.7%, after dose 1 and 15.3% to 17.4% after dose 2) with similar proportions in the full and split MQ arms. The open-label design is a limitation of the study that affects mainly the safety assessment.Conclusions
Women taking MQ IPTp (15 mg/kg) in the context of long lasting insecticide treated nets had similar prevalence rates of low birth weight as those taking SP IPTp. MQ recipients had less clinical malaria than SP recipients, and the pregnancy outcomes and safety profile were similar. MQ had poorer tolerability even when splitting the dose over two days. These results do not support a change in the current IPTp policy.Trial registration
ClinicalTrials.gov ; NCT 00811421Pan African Clinical Trials Registry PACTR 2010020001429343 Please see later in the article for the Editors'' Summary 相似文献997.
摘要目的:牙周病是由多种因素引起的,特别是人牙周膜细胞的缺失。转化生长因子-β1(TGF-β1)是一种多功能细胞因子,在治
疗牙周病中发挥重要的作用,但很少有人清楚地研究TGF-β1 对人牙周膜细胞的影响。因此,本研究的目的是探讨TGF-β1诱导
人牙周膜细胞细胞骨架重排的信号通路。方法:人牙周膜细胞取自健康的前磨牙,并向同步化处理的细胞中加入10 ng / ml 的
TGF-β1,并通过相差显微镜观察它们的形态学变化。通过免疫组化和共聚焦显微镜观察F-肌动蛋白重排。用Western blot 分析蛋
白表达情况。结果:我们发现TGF-β1 诱导人牙周膜细胞细胞骨架重排,激活ROCK 蛋白的表达,并增加p-lIMK 和p-cofilin 的
蛋白表达。ROCK 抑制剂Y-27632 使ROCK,p-lIMK 和p-cofilin 的蛋白表达下降。结论:TGF-β1可以诱导人牙周膜细胞细胞骨架
重排,并且是通过上凋ROCK,p-lIMK 和p-cofilin 的活性完成的。本研究可以增强对TGF-β1 在治疗牙周疾病方面的作用机制的
了解。 相似文献
998.
J.M. Ou Z.Y. Yu M.K. Qiu Y.X. Dai Q. Dong J. Shen P. Dong X.F. Wang Y.B. Liu Z.W. Quan Z.W. Fei 《European journal of histochemistry : EJH》2014,58(1)
Angiogenesis is a process of development and growth of new capillary blood vessels from pre-existing vessels. Angiogenic growth factors play important roles in the development and maintenance of some malignancies, of which vascular endothelial growth factor (VEGF)/VEGFR2 interactions are involved in proliferation, migration, and survival of many cancer cells. The aim of this study was to investigate the function of VEGFR2 in human hemangiomas (HAs). Using immunohistochemistry assay, we examined the expression levels of VEGF, VEGFR2, Ki-67, glucose transporter-1 (Glut-1), phosphorylated protein kinase B (p-AKT) and p-ERK in different phases of human HAs. Positive expression of VEGF, VEGFR2, Ki-67, Glut-1, p-AKT and p-ERK was significantly increased in proliferating phase HAs, while decreased in involuting phase HAs (P=0.001; P=0.003). In contrast, cell apoptotic indexes were decreased in proliferating phase HAs, but increased in involuting phase HAs (P<0.01). Furthermore, we used small hairpin RNA (shRNA)-mediated VEGFR2 knockdown in primary HA-derived endothelial cells (HemECs) to understand the role of VEGF/VEGFR2 signaling. Knockdown of VEGFR2 by Lv-shVEGFR2 inhibited cell viability and induced apoptosis in primary HemECs companied with decreased expression of p-AKT, p-ERK, p-p38MAPK and Ki-67 and increased expression of caspase-3 (CAS-3); Overexpression of VEGFR2 promoted cell viability and blocked apoptosis in Lv-VEGFR2-transfected HemECs. Taken together, our findings demonstrate that, increased expression of VEGFR2 is involved in the development of primary HemECs possibly through regulation of the AKT and ERK pathways, suggesting that VEGFR2 may be a potential therapeutic target for HAs.Key words: vascular endothelial growth factor receptor 2, hemangioma, proliferation, apoptosis 相似文献
999.
Hui?Wang Cheng-Gang?Ou Fei-Yun?ZhuangEmail author Zhen-Guo?Ma 《Molecular breeding : new strategies in plant improvement》2014,34(4):2065-2079
Carrot (Daucus carota L.) is an important food crop and is useful for studying carotenogenesis due to the quantity and diversity of carotenoids in its roots. Phytoene synthase catalyzes the first committed step in the carotenoid biosynthesis pathway, and its overexpression is the main driving force in the orange phenotype. At present, we lack fundamental knowledge of the role of these genes and their effects on carotenoid accumulation in leaves. In the present study, three backcross inbred lines (BC2S4) with different colored roots derived from a cross between the orange inbred line (Af) and related wild species were used to investigate the role of the duplicated DcPSY genes in root carotenogenesis. Promoter analysis showed that DcPSY genes have diverged substantially in their regulatory sequences after gene duplication. Expression levels of DcPSY1 and DcPSY2 were generally positively correlated with carotenoid content during root development. In mature leaves, total carotenoid content was higher than that in the roots, DcPSY1 expression increased extremely higher than DcPSY2 expression compared with roots, and DcPSY1 was more sensitive than DcPSY2 during leaf de-etiolation under sunlight. These results suggest that DcPSY1 seems to make an important contribution to carotenoid accumulation in the leaves and is important for photosynthesis and photoprotection, but they are not the determining factors of root color. This expands our understanding of the regulation of carotenoid biosynthesis in carrot. 相似文献
1000.
Fei Gao Yudong Xia Junwen Wang Zhilong Lin Ying Ou Xing Liu Weilong Liu Boping Zhou Huijuan Luo Baojin Zhou Bo Wen Xiuqing Zhang Jian Huang 《Genome biology》2014,15(12)