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981.
Allelopathy of diterpenoids extracted from plants of the genus Robdosia on three common species of soil ciliates, Colpoda inflata, Colpoda cucullus and Euplotes muscicola, was studied by acute toxicity test, sub-lethal effect test and morphological observation. Acute toxicity test showed that there was remarkable toxicity of the diterpenoids on the individuals of the three soil ciliate species, and there was close correlation between toxicity and concentration of the diterpenoids. 12 h-LC50 values of the diterpenoids on the individuals of C. inflata, C. cucullus and E. muscicola were 161.40 mg L?1, 94.80 mg L?1 and 83.70 mg L?1 respectively, and 24 h-LC50 values were 114.90 mg L?1, 92.30 mg L?1and 65.80 mg L?1 separately. Sub-lethal effect test of soil ciliates suggested that there existed significant inhibition of the diterpenoids on population growth of the three ciliates with dose-dependant relationships, population density and growth rate of the test group was obviously lower than that of the control group. Morphological observation indicated that diterpenoids affected the body shapes of the three ciliates and made them shorter and thicker, and the higher the concentration of diterpenoids, the greater the affection. The results are of great significance for understanding the functions of ciliates and their relationships to other organisms, and for the application of allelopathy in biological pest control in the soil ecosystems. 相似文献
982.
Protein splicing is a precise post-translational process mediated by inteins. Inteins are intervening proteins that cleave
themselves from a precursor protein while joining the flanking sequences. Here we report the 15N, 13C, and 1H chemical shift assignments of the intein from DNA polymerase II of Pyrococcus abyssi (Pab PolII intein), which has been recombinantly overexpressed and isotopically labeled. The NMR assignments of Pab PolII intein are essential for solution structure determination and protein dynamics study. 相似文献
983.
Boden G Song W Duan X Cheung P Kresge K Barrero C Merali S 《Obesity (Silver Spring, Md.)》2011,19(7):1366-1373
Endoplasmic reticulum (ER) stress has recently been implicated as a cause for obesity-related insulin resistance; however, what causes ER stress in obesity has remained uncertain. Here, we have tested the hypothesis that macronutrients can cause acute (ER) stress in rat liver. Examined were the effects of intravenously infused glucose and/or lipids on proximal ER stress sensor activation (PERK, eIF2-α, ATF4, Xbox protein 1 (XBP1s)), unfolded protein response (UPR) proteins (GRP78, calnexin, calreticulin, protein disulphide isomerase (PDI), stress kinases (JNK, p38 MAPK) and insulin signaling (insulin/receptor substrate (IRS) 1/2 associated phosphoinositol-3-kinase (PI3K)) in rat liver. Glucose and/or lipid infusions, ranging from 23.8 to 69.5 kJ/4 h (equivalent to between ~17% and ~50% of normal daily energy intake), activated the proximal ER stress sensor PERK and ATF6 increased the protein abundance of calnexin, calreticulin and PDI and increased two GRP78 isoforms. Glucose and glucose plus lipid infusions induced comparable degrees of ER stress, but only infusions containing lipid activated stress kinases (JNK and p38 MAPK) and inhibited insulin signaling (PI3K). In summary, physiologic amounts of both glucose and lipids acutely increased ER stress in livers 12-h fasted rats and dependent on the presence of fat, caused insulin resistance. We conclude that this type of acute ER stress is likely to occur during normal daily nutrient intake. 相似文献
984.
Dufau S Duñabeitia JA Moret-Tatay C McGonigal A Peeters D Alario FX Balota DA Brysbaert M Carreiras M Ferrand L Ktori M Perea M Rastle K Sasburg O Yap MJ Ziegler JC Grainger J 《PloS one》2011,6(9):e24974
Investigating human cognitive faculties such as language, attention, and memory most often relies on testing small and homogeneous groups of volunteers coming to research facilities where they are asked to participate in behavioral experiments. We show that this limitation and sampling bias can be overcome by using smartphone technology to collect data in cognitive science experiments from thousands of subjects from all over the world. This mass coordinated use of smartphones creates a novel and powerful scientific "instrument" that yields the data necessary to test universal theories of cognition. This increase in power represents a potential revolution in cognitive science. 相似文献
985.
986.
Background
Coronary atherosclerosis, the main cause of cardiovascular disease, is a progressive disease. Recent Genome Wide Association Studies (GWASs) discovered several novel loci associated with coronary artery disease (CAD) or its main complication myocardial infarction (MI). In this study, we investigated the associations between previously reported CAD- and MI-associated variants and coronary atherosclerosis in Chinese Han population.Methodology/Principal Findings
We performed a case-control association study with 2,335 coronary atherosclerosis patients and 1,078 controls undergoing coronary angiography of Chinese Han from China. Fourteen single nucleotide polymorphisms (SNPs), located at 1p13.3, 1q41, 2q36.3, 6q25.1, 9p21.3, 10q11.21 and 15q22.33, were genotyped in our sample collection. Six SNPs at 9p21 were associated with coronary atherosclerosis susceptibility (Ptrend<0.05) and rs10757274 showed the most significant association (P = 2.38×10−08, OR = 1.34). These associations remained significant after adjustment for multiple comparisons. Rs17465637 at 1q41 (Ptrend = 6.83×10−03, OR = 0.86) also showed significant association with coronary atherosclerosis, but the association was not significant after multiple comparisons. Additionally, rs501120 (P = 8.36×10−03, OR = 0.80) at 10q11.21 was associated with coronary atherosclerosis in females, but did not show association in males and all participants. Variants at 1p13.3, 2q36.3, 6q25.1 and 15q22.33 showed no associations with coronary atherosclerosis and main cardiovascular risk factors in our data.Conclusions/Significance
Our findings indicated variants at 9p21 were significantly associated with coronary atherosclerosis in Han Chinese. Variants at 1q41 showed suggestive evidence of association and variants at 10q11.21 showed suggestive evidence of association in females, which warrant further study in a larger sample. 相似文献987.
Identification of miRs-143 and -145 that is associated with bone metastasis of prostate cancer and involved in the regulation of EMT 总被引:1,自引:0,他引:1
Peng X Guo W Liu T Wang X Tu X Xiong D Chen S Lai Y Du H Chen G Liu G Tang Y Huang S Zou X 《PloS one》2011,6(5):e20341
The principal problem arising from prostate cancer (PCa) is its propensity to metastasize to bone. MicroRNAs (miRNAs) play a crucial role in many tumor metastases. The importance of miRNAs in bone metastasis of PCa has not been elucidated to date. We investigated whether the expression of certain miRNAs was associated with bone metastasis of PCa. We examined the miRNA expression profiles of 6 primary and 7 bone metastatic PCa samples by miRNA microarray analysis. The expression of 5 miRNAs significantly decreased in bone metastasis compared with primary PCa, including miRs-508-5p, -145, -143, -33a and -100. We further examined other samples of 16 primary PCa and 13 bone metastases using real-time PCR analysis. The expressions of miRs-143 and -145 were verified to down-regulate significantly in metastasis samples. By investigating relationship of the levels of miRs-143 and -145 with clinicopathological features of PCa patients, we found down-regulations of miRs-143 and -145 were negatively correlated to bone metastasis, the Gleason score and level of free PSA in primary PCa. Over-expression miR-143 and -145 by retrovirus transfection reduced the ability of migration and invasion in vitro, and tumor development and bone invasion in vivo of PC-3 cells, a human PCa cell line originated from a bone metastatic PCa specimen. Their upregulation also increased E-cadherin expression and reduced fibronectin expression of PC-3 cells which revealed a less invasive morphologic phenotype. These findings indicate that miRs-143 and -145 are associated with bone metastasis of PCa and suggest that they may play important roles in the bone metastasis and be involved in the regulation of EMT Both of them may also be clinically used as novel biomarkers in discriminating different stages of human PCa and predicting bone metastasis. 相似文献
988.
989.
Herpesvirus of turkey (HVT) is being widely used as a vector for development of recombinant vaccines and US2 and US10 genes are often chosen as insertion sites for targeted gene expression. However, the different effects of the two genes for generation of recombinant HVT vaccines were unknown. In order to compare the effects of inserted genes in the two sites on the efficacy of the recombinant vaccines, host-protective haemagglutinin (HA) gene of the highly pathogenic avian influenza virus (HPAIV) H5N1 was inserted into either US2 or US10 gene locus of the HVT. The resulting US2 (rHVT-US2-HA) or US10 (rHVT-US10-HA) recombinant HVT viruses were used to infect chicken embryo fibroblasts. Plaques and the growth kinetics of rHVT-US2-HA-infected chicken embryo fibroblasts were similar to those of parental HVT whereas rHVT-US10-HA infected chicken embryo fibroblasts had different growth kinetics and plaque formation. The viremia levels in rHVT-US10-HA virus-infected chickens were significantly lower than those of rHVT-US2-HA group on 28 days post infection. The vaccine efficacy of the two recombinant viruses against H5N1 HPAIV and virulent Marek's disease virus was also evaluated in 1-day-old vaccinated chickens. rHVT-US2-HA-vaccinated chickens were better protected with reduced mortality than rHVT-US10-HA-vaccinated animals following HPAIV challenge. Furthermore, the overall hemaglutination inhibition antibody titers of rHVT-US2-HA-vaccinated chickens were higher than those of rHVT-US10-HA-vaccinated chickens. Protection levels against Marek's disease virus challenge following vaccination with either rHVT-US2-HA or rHVT-US10-HA, however, were similar to those of the parental HVT virus. These results, for the first time, indicate that US2 gene provides a favorable foreign gene insertion site for generation of recombinant HVT vaccines. 相似文献
990.