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961.
962.
The dysregulation of miR-137 plays vital roles in the oncogenesis and progression of various types of cancer, but its role in prognosis of gastric cancer patients remains unknown. This study was designed to investigate the expression and prognostic significance of miR-137 in gastric cancer patients after radical gastrectomy. Quantitative real-time PCR (qRT-PCR) was performed to evaluate the expression of miR-137 in human gastric cancer cell lines and tissues in patients with gastric adenocarcinoma. Results were assessed for association with clinical factors and overall survival by using Kaplan-Meier analysis. Prognostic values of miR-137 expression and clinical outcomes were evaluated by Cox regression analysis. The results exhibited that the expression level of miR-137 was decreased in human gastric cancer cell lines and tissues, and down-regulated expression of miR-137 was associated with tumor cell differentiation, N stage, and TNM stage. Decreased miR-137 expression in gastric cancer tissues was positively correlated with poor overall survival of gastric cancer patients. Further multivariate Cox regression analysis suggested that miR-137 expression was an independent prognostic indicator for gastric cancer except for TNM stage. Applying the prognostic value of miR-137 expression to TNM stage III group showed a better risk stratification for overall survival. In conclusion, the results reinforced the critical role for the down-regulated miR-137 expression in gastric cancer and suggested that miR-137 expression could be a prognostic indicator for this disease. In addition, these patients with TNM stage III gastric cancer and low miR-137 expression might need more aggressive postoperative treatment and closer follow-up. 相似文献
963.
Xiangrong Dong Bing Tian Shang Dai Tao Li Linna Guo Zhongfang Tan Zhen Jiao Qingsheng Jin Yanping Wang Yuejin Hua 《PloS one》2015,10(11)
PprI is a general switch protein that regulates the expression of certain proteins involved in pathways of cellular resistance in the extremophilic bacterium Deinococcus radiodurans. In this study, we transformed pprI into Lactococcus lactis strain MG1363 using the lactococcal shuttle vector pMG36e and investigated its effects on the tolerance and lactic acid production of L. lactis while under stress. PprI was stably expressed in L. lactis as confirmed by western blot assays. L. lactis expressing PprI exhibited significantly improved resistance to oxidative stress and high osmotic pressure. This enhanced cellular tolerance to stressors might be due to the regulation of resistance-related genes (e.g., recA, recO, sodA, and nah) by pprI. Moreover, transformed L. lactis demonstrated increased lactic acid production, attributed to enhanced lactate dehydrogenase activity. These results suggest that pprI can improve the tolerance of L. lactis to environmental stresses, and this transformed bacterial strain is a promising candidate for industrial applications of lactic acid production. 相似文献
964.
Objective
This study aimed to determine the optimal Foley catheter balloon volume (30-mL vs. 80-mL) and the maximum time for cervical ripening (12 hours vs. 24 hours) to improve vaginal delivery rate within 24 hours of induction.Methods
We conducted an open-label, randomized controlled trial in a teaching hospital in China. Women with a term singleton pregnancy, cephalic presentation, intact membrane and an unfavorable cervix (Bishop score <6) were randomly allocated, in 1:1:1:1 ratio, to receive either one of the four treatments: (1) 30-mL balloon for a maximum of 12 hours, (2) 30-mL balloon for a maximum of 24 hours, (3) 80-mL balloon for a maximum of 12 hours, and (4) 80-mL balloon for a maximum of 24 hours. The primary outcome was vaginal delivery within 24 hours. Secondary outcomes included cesarean section rate and maternal/neonatal morbidity. Data were analyzed on a per-protocol basis.Results
Five hundred and four women were recruited and randomized (126 women in each group); nine women did not receive the assigned intervention. More women achieved vaginal delivery within 24 hours in 12-hour Foley catheter groups than in the 24-hour Foley catheter groups (30-mL/12 hours: 54.5%, 30-mL/24 hours: 33.1%, 80-mL/12 hours: 46.4%, 80-mL/24 hours: 24.0%, p < 0.001). Cesarean section rates and the incidence of chorioaminonitis were comparable among four groups. After adjustment for confounding factors, both ripening time and balloon size did not affect the proportion of women delivered vaginally within 24 hours of induction.Conclusion
For women with an unfavorable cervix at term, induction of labor with a Foley catheter is safe and effective. Higher balloon volume (80-mL vs. 30-mL) and longer ripening time (24 hours vs. 12 hours) would not shorten induction to delivery interval or reduce cesarean section rate.Trial Registration
Chinese Clinical trial registry (ChiCTR-TRC-13003044) 相似文献965.
Northeast China is an intensive area of resource-exhausted city, which is facing the challenges of industry conversion and sustainable development. In order to evaluate the soil environmental quality influenced by mining activities over decades, the concentration and spatial distribution of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and Zinc (Zn) in surface soils (0-20cm) of a typical resource-exhausted city were investigated by analyzing 306 soil samples. The results showed that the average concentrations in the samples were 6.17 mg/kg for As, 0.19 mg/kg for Cd, 51.08 mg/kg for Cr, 23.27 mg/kg for Cu, 31.15 mg/kg for Ni, 22.17 mg/kg for Pb, and 54.21 mg/kg for Zn. Metals distribution maps produced by using the inverse distance weighted interpolation method and results revealed that all investigated metals showed distinct geographical patterns, and the concentrations were higher in urban and industrial areas than in farmland. Pearson correlation and principal component analysis showed that there were significant positive correlations (p<0.05) between all of the metals, and As, Cd, Cr, Mn, Ni, Pb, and Zn were closely associated with the first principal component (PC1), which explained 39.81% of the total variance. Cu and As were mainly associated with the second component (PC2). Based on the calculated Nemerow pollution index, percentage for slightly polluted (1<P ≤ 2) surface soils were reached 57.33%, while 42.65% topsoil samples are moderate polluted (2<P≤ 3). According to the results above-mentioned, different soil environmental function areas were classified and proper soil environmental management policy was proposed to decrease the environmental risks in the process of industrial city transformation. 相似文献
966.
Kawsar R. Talaat Subash Babu Pradeep Menon N. Kumarasamy Jabin Sharma Jeeva Arumugam Kalaivani Dhakshinamurthy Ramalingam Srinivasan S. Poongulali Wenjuan Gu Michael P. Fay Soumya Swaminathan Thomas B. Nutman 《PLoS neglected tropical diseases》2015,9(3)
BackgroundThe disease course of human immunodeficiency virus (HIV) is often altered by existing or newly acquired coincident infections.Conclusions/SignificanceWe were unable to find a significant effect of W. bancrofti infection or its treatment on HIV clinical course or surrogate markers of HIV disease progression though we recognized that our study was limited by the smaller than predicted sample size and by the use of ART in half of the patients. Treatment of W. bancrofti coinfection in HIV positive subjects (as is usual in mass drug administration campaigns) did not represent an increased risk to the subjects, and should therefore be considered for PLWHA living in W. bancrofti endemic areas.
Trial Registration
ClinicalTrials.gov NCT00344279相似文献967.
Effect of Bcl‐xL overexpression on sialylation of Fc‐fusion protein in recombinant Chinese hamster ovary cell cultures 下载免费PDF全文
The sialic acid of glycoproteins secreted by recombinant Chinese hamster ovary (rCHO) cells can be impaired by sialidase under culture conditions which promote the extracellular accumulation of this enzyme. To investigate the effect of Bcl‐xL overexpression on the sialylation of glycoproteins produced in rCHO cell culture, two rCHO cell lines producing the same Fc‐fusion protein, which were derived from DUKX‐B11 and DG44, respectively, were engineered to have regulated Bcl‐xL overexpression using the Tet‐off system. For both cell lines, Bcl‐xL overexpression improved cell viability and extended culture longevity in batch cultures. As a result, a maximum Fc‐fusion protein titer increased by Bcl‐xL overexpression though the extent of titer enhancement differed between the two cell lines. With Bcl‐xL overexpression, the sialylation of Fc‐fusion protein, which was assessed by isoelectric focusing gel and sialic acid content analyses, decreased more slowly toward the end of batch cultures. This was because Bcl‐xL overexpression delayed the extracellular accumulation of sialidase activity by reducing cell lysis during batch cultures. Taken together, Bcl‐xL overexpression in rCHO cell culture increased Fc‐fusion protein production and also reduced the impairment of sialylation of Fc‐fusion protein by maintaining high viability during batch cultures. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1133–1136, 2015 相似文献
968.
Haifeng Zhang Na Gao Tingting Liu Yan Fang Bing Qi Qiang Wen Jun Zhou Linjing Jia Hailing Qiao 《PloS one》2015,10(6)
Human cytochrome b5 (Cyt b5) plays important roles in cytochrome P450 (CYP)-mediated drug metabolism. However, the expression level of Cyt b5 in normal human liver remains largely unknown. The effect of Cyt b5 on overall CYP activity in human liver microsomes (HLM) has rarely been reported and the relationship between Cyt b5 and the activity of polymorphic CYP has not been systematically investigated. In this study, we found that the median value of Cyt b5 protein was 270.01 pmol/mg from 123 HLM samples, and 12- and 19-fold individual variation was observed in Cyt b5 mRNA and protein levels, respectively. Gender and smoking clearly influenced Cyt b5 content. In addition, we found that Cyt b5 protein levels significantly correlated with the overall activity of CYP1A2, 2B6, and 2E1 in HLM. However, when the CYP activities were sorted by single nucleotide polymorphisms (SNP), the effect of Cyt b5 protein on the kinetic parameters varied greatly. There were significant correlations between Cyt b5 content and Vmax and CLint of CYP1A2 wild-types (3860GG, 2159GG, and 5347CC) as well as homozygous mutants (163AA and 3113GG). In contrast to Vmax and CLint, the Km of CYP2B6 516GG and 785AA genotypes was inversely associated with Cyt b5 content. Correlations between Cyt b5 content and Vmax and CLint of CYP2E1 -1293GG, -1293GC, 7632TT, 7632TA, -333TT, and -352AA genotypes were also observed. In conclusion, Cyt b5 expression levels varied considerably in the Chinese cohort from this study. Cyt b5 had significant impact on the overall activity of CYP1A2, 2B6, and 2E1 in HLM and the effects of Cyt b5 protein on polymorphic CYP1A2, 2B6, and 2E1 activity were SNP-dependent. These findings suggest that Cyt b5 plays an important role in CYP-mediated activities in HLM and may possibly be a contributing factor for the individual variation observed in CYP enzyme activities. 相似文献
969.
Noelle A. Benzekri Jacques Sambou Binetou Diaw El Hadji Ibrahima Sall Fatima Sall Alassane Niang Selly Ba Ndèye Fatou Ngom Guèye Mouhamadou Ba?la Diallo Stephen E. Hawes Moussa Seydi Geoffrey S. Gottlieb 《PloS one》2015,10(11)