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61.
Caenorhabditis elegans is a simple genetic organism amenable to large-scale forward and reverse genetic screens and chemical genetic screens. The C. elegans genome includes potential antipsychotic drug (APD) targets conserved in humans, including genes encoding proteins required for neurotransmitter synthesis and for synaptic structure and function. APD exposure produces developmental delay and/or lethality in nematodes in a concentration-dependent manner. These phenotypes are caused, in part, by APD-induced inhibition of pharyngeal pumping1,2. Thus, the developmental phenotype has a neuromuscular basis, making it useful for pharmacogenetic studies of neuroleptics. Here we demonstrate detailed procedures for testing APD effects on nematode development and pharyngeal pumping. For the developmental assay, synchronized embryos are placed on nematode growth medium (NGM) plates containing APDs, and the stages of developing animals are then scored daily. For the pharyngeal pumping rate assay, staged young adult animals are tested on NGM plates containing APDs. The number of pharyngeal pumps per unit time is recorded, and the pumping rate is calculated. These assays can be used for studying many other types of small molecules or even large molecules. 相似文献
62.
Late-acting self-incompatibility in tea plant (<Emphasis Type="Italic">Camellia sinensis</Emphasis>)
The self-incompatibility of tea plant (Camellia sinensis (L.) O. Kuntze) was studied with the methods of aniline blue fluorescence assay and paraffin sections. The characteristics
of pollen tube elongation after hand pollination was analyzed in 4 tea cultivars, including ‘Keemenzhong’, ‘Longjing-changye’,
‘Fuding-dabaicha’ and ‘Yabukita’, under self-pollination and cross-pollination, respectively. Although there were some difference
among cultivars, pollen tubes elongated through the style and reach the ovary successfully at 48 h after pollination for both
cross- and self-pollen tubes in all the four cultivars of tea. Pollen tubes entered into the ovule micropyles, however, only
for cross-pollination, but not for self-pollination. Pollen tubes of selfing plants, failed in fertilizing, seemed have some
difficulties to enter the ovule. All of which indicated that the self-incompatibility of tea plant is a late-acting self-incompatibility
system (LSI) or an ovarian sterility (OS), in which the self incompatibility was due to none self pollen tube penetrating
into the ovule and no fertilization. 相似文献
63.
Wen-Jie Mu Wen-Jing Zhong Ji-Yi Yao Lu-Jing Li Yu-lan Peng Yi Wang Li-sha Liu Ying Xiao Shou-jun Liu Chang-jun Wu Yu-xin Jiang Shyam Sundar Parajuly Ping Xu Yi Hao Jing Li Bao-Ming Luo Hui Zhi 《PloS one》2016,11(2)
Background
This study aimed to confirm whether strain ratio should be added after evaluation of lesions with 5-point elasticity scoring for differentiating benign and malignant breast lesions on ultrasonographic elastography(UE).Materials and Methods
From June 2010 to March 2012, 1080 consecutive female patients with breast lesions were recruited into a multicenter retrospective study, which involved 8 centers across China. Each institutional ethic review board approved the study, and all the patients gave written informed consent. All the patients underwent the UE procedure and the strain ratios were calculated and the final diagnosis was made by histological findings. The sensitivity, specificity, accuracy, PPV and NPV were calculated for each of the two evaluation systems and the areas under the ROC curve were compared.Results
The strain ratios of benign lesions (mean, 2.6±2.0) and malignant lesions (mean,7.9±5.8) were significantly different (p <0.01). When the cutoff point was 3.01, strain ratio method had 79.8% sensitivity, 82.8% specificity, and 81.3% accuracy, while the 5-point scoring method had 93.1% sensitivity, 73.0% specificity, and 76.8% accuracy. The areas under the ROC curve with the strain ratio method and 5-point scoring method were 0.863 and 0.865, respectively(p>0.05). The strain ratio method shows better a diagnosis performance of the lesions with elasticity score 3 and 4.Conclusions
Although the two UE methods have similar diagnostic performance, separate calculation of the strain ratios seems compulsory, especially for the large solid breast lesions and the lesions with elasticity score 3 and 4. 相似文献64.
Activation of brain steroidogenesis and neurogenesis during the gonadal differentiation in protandrous black porgy,Acanthopagrus schlegelii 下载免费PDF全文
Chien‐Ju Lin Yi‐Chun Fan‐Chiang Sylvie Dufour Ching‐Fong Chang 《Developmental neurobiology》2016,76(2):121-136
The early brain development, at the time of gonadal differentiation was investigated using a protandrous teleost, black porgy. This natural model of monosex juvenile fish avoids the potential complexity of sexual dimorphism. Brain neurogenesis was evaluated by histological analyses of the diencephalon, at the time of testicular differentiation (in fish between 90 and 150 days after hatching). Increases in the number of both Nissl‐stained total brain cells, and Pcna‐immunostained proliferative brain cells were observed in specific area of the diencephalon, such as ventromedialis thalami and posterior preoptic area, revealing brain cell proliferation. qPCR analyses showed significantly higher expression of the radial glial cell marker blbp and neuron marker bdnf. Strong immunohistochemical staining of Blbp and extended cellular projections were observed. A peak expression of aromatase (cyp19a1b), as well as an increase in estradiol (E2) content were also detected in the early brain. These data demonstrate that during gonadal differentiation, the early brain exhibits increased E2 synthesis, cell proliferation, and neurogenesis. To investigate the role of E2 in early brain, undifferentiated fish were treated with E2 or aromatase inhibitor (AI). E2 treatment upregulated brain cyp19a1b and blbp expression, and enhanced brain cell proliferation. Conversely, AI reduced brain cell proliferation. Castration experiment did not influence the brain gene expression patterns and the brain cell number. Our data clearly support E2 biosynthesis in the early brain, and that brain E2 induces neurogenesis. These peak activity patterns in the early brain occur at the time of gonad differentiation but are independent of the gonads. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 121–136, 2016 相似文献
65.
Resveratrol (trans-3,4,5’ –trihydroxystilbene) is an active compound in food, such as red grapes, peanuts, and berries. Resveratrol exhibits an anticancer effect on various human cancer cells. However, the mechanism of resveratrol-induced anti-cancer effect at the molecular level remains to be elucidated. In this study, the mechanism underlying the anti-cancer effect of resveratrol in human ovarian cancer cells (OVCAR-3 and Caov-3) was investigated using various molecular biology techniques, such as flow cytometry, western blotting, and RNA interference, with a major focus on the potential role of autophagy in resveratrol-induced apoptotic cell death. We demonstrated that resveratrol induced reactive oxygen species (ROS) generation, which triggers autophagy and subsequent apoptotic cell death. Resveratrol induced ATG5 expression and promoted LC3 cleavage. The apoptotic cell death induced by resveratrol was attenuated by both pharmacological and genetic inhibition of autophagy. The autophagy inhibitor chloroquine, which functions at the late stage of autophagy, significantly reduced resveratrol-induced cell death and caspase 3 activity in human ovarian cancer cells. We also demonstrated that targeting ATG5 by siRNA also suppressed resveratrol-induced apoptotic cell death. Thus, we concluded that a common pathway between autophagy and apoptosis exists in resveratrol-induced cell death in OVCAR-3 human ovarian cancer cells. 相似文献
66.
在黄花蒿(Artemisia annua L.)发根液体培养中,黄花蒿内生炭疽菌(Colletotrichum sp. B501)细胞壁寡糖提取物可促进发根青蒿素的合成.经寡糖诱导子(20 mg/L)处理4 d后,发根青蒿素含量达1.15 mg/g, 比对照高出64.29%.诱导作用与诱导子浓度、作用时间相关.诱导处理1 d后,X射线能谱分析表明黄花蒿发根细胞中Ca2+积累量显著增高,电镜观察发现液泡内出现高电子致密物,具活性氧清除作用的过氧化物酶表现出高活性(6.5 unit*min-1*g-1 FW).诱导处理第三天,细胞核DNA呈梯度条带降解,部分细胞出现程序化死亡.内生菌细胞壁寡糖提取物引起的生理反应有利于细胞中青蒿素的生物合成. 相似文献
67.
Asymmetric distribution of phosphatidylethanolamine in the membrane of vesicular stomatitis virus. 总被引:3,自引:3,他引:3 下载免费PDF全文
The membrane-impermeable reagent trinitrobenzenesulfonate has been shown to react only with the surface components of vesicular stomatitis virus (VSV) membranes. When the amount of phosphatidylethanolamine (PE) available to modification by trinitrobenzenesulfonate in intact virions was determined, it was found that 36% of the total membrane PE was converted to the trinitrophenyl derivative. The same proportion of the total membrane PE was reactive after removal of the surface glycoprotein by trypsin digestion, but disruption of the virus membrane by sonication rendered all of the PE reactive. These results indicate that PE is asymmetrically distributed in the VSV membrane; 36% is present in the outer lipid leaflet, whereas 64% is found on the inner layer. 相似文献
68.
Rong Xu QingFeng Han TongYing Zhu Yeping Ren JiangHua Chen HuiPing Zhao MengHua Chen Jie Dong Yue Wang ChuanMing Hao Rui Zhang Xiaohui Zhang Mei Wang Na Tian HaiYan Wang 《PloS one》2013,8(11)
Background
Diabetic patients on peritoneal dialysis (PD) have lower survival and are more likely complicated with inflammation than their non-diabetic counterparts. Here, we explored the interaction effects between diabetes and inflammation on the survival of PD patients.Methods
Overall, 2,264 incident patients were enrolled from a retrospective cohort study in China. Patients were grouped according to the baseline levels of high-sensitive C-reactive protein (hsCRP, ≤3 mg/L or >3 mg/L) or serum albumin (SA, ≥38 g/L or <38 g/L). Then, several multivariable adjusted stratified Cox regression models were constructed for these groups to explore the predicted role of diabetes on all-cause or cardiovascular death under inflammatory or non-inflammatory conditions.Results
Diabetics on PD were more likely to have inflammation than non-diabetics on PD, and they presented with elevated hsCRP (52.7% vs. 47.3%, P = 0.03) or decreased SA (77.9% vs. 62.7%, P < 0.001) levels. After stratification by size of center and controlling for confounding factors, diabetes was found to predict all-cause death in patients with hsCRP >3 mg/L or SA <38 g/L but not in patients with hsCRP ≤3 mg/L or SA ≥38 g/L. Similarly, the presence of diabetes was an indication of cardiovascular death in patients with hsCRP >3 mg/L or SA <38 g/L. However, if further adjusted by baseline cardiovascular disease, the predicted role of diabetes on death related to cardiovascular disease in patients with SA <38 g/L disappeared.Conclusion
Diabetic patients could do as well as non-diabetic patients without inflammation on peritoneal dialysis. Active strategies should be implemented to improve inflammation status in diabetic patients on PD. 相似文献69.
David Fong Martine Bisson Gino Laberge Stephen McManus Guillaume Grenier Nathalie Faucheux Sophie Roux 《Cellular signalling》2013,25(4):717-728
BMP-9 is a potent osteogenic factor; however, its effects on osteoclasts, the bone-resorbing cells, remain unknown. To determine the effects of BMP-9 on osteoclast formation, activity and survival, we used human cord blood monocytes as osteoclast precursors that form multinucleated osteoclasts in the presence of RANKL and M-CSF in long-term cultures. BMP-9 did not affect osteoclast formation, but adding BMP-9 at the end of the culture period significantly increased bone resorption compared to untreated cultures, and reduced both the rate of apoptosis and caspase-9 activity. BMP-9 also significantly downregulated the expression of pro-apoptotic Bid, but only after RANKL and M-CSF, which are both osteoclast survival factors, had been eliminated from the culture medium. To investigate the mechanisms involved in the effects of BMP-9, we first showed that osteoclasts expressed some BMP receptors, including BMPR-IA, BMPR-IB, ALK1, and BMPR-II. We also found that BMP-9 was able to induce the phosphorylation of Smad-1/5/8 and ERK 1/2 proteins, but did not induce p38 phosphorylation. Finally, knocking down the BMPR-II receptor abrogated the BMP-9-induced ERK-signaling, as well as the increase in bone resorption. In conclusion, these results show for the first time that BMP-9 directly affects human osteoclasts, enhancing bone resorption and protecting osteoclasts against apoptosis. BMP-9 signaling in human osteoclasts involves the canonical Smad-1/5/8 pathway, and the ERK pathway. 相似文献
70.
Leixiang Yang Jingxu Gong Feng Wang Yongmin Zhang Yanguang Wang Xiaojiang Hao 《Journal of enzyme inhibition and medicinal chemistry》2013,28(4):399-404
In this work, we evaluated the antioxidant properties of the eight novel silybin analogues for their capacity to scavenge free radicals including superoxide anion radicals and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals in vitro. Compound 7d demonstrated an excellent antioxidant effect in scavenging superoxide anion free radical with an IC50 value of 26.5 μM, while the IC50 of quercetin (the reference compound) was 38.1 μM. Compounds 7b, 7e, 7h showed certain scavenging activities for both types of free radicals. 相似文献