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161.
Lectin from crude extract of small black kidney bean (Phaseolus vulgaris) was successfully extracted using the reversed micellar extraction (RME). The effects of water content of organic phase (Wo), ionic strength, pH, Aerosol-OT (AOT) concentration and extraction time on the forward extraction and the pH and ionic strength in the backward extraction were studied to optimize the extraction efficiency and purification factor. Forward extraction of lectin was found to be maximum after 15 min of contact using 50 mM AOT in organic phase with Wo 27 and 10 mM citrate-phosphate buffer at pH 5.5 containing 100 mM NaCl in the aqueous phase. Lectin was backward extracted into a fresh aqueous phase using sodium-phosphate buffer (10 mM, pH 7.0) containing 500 mM KCl. The overall yield of the process was 53.28% for protein recovery and 8.2-fold for purification factor. The efficiency of the process was confirmed by gel electrophoresis analysis. 相似文献
162.
Li-Hai Fan Zi-Jian Zhang Xiao-Yu Yu Ya-Xu Xue Miao-Miao Wang Tian-Wei Tan 《Process Biochemistry》2013,48(3):430-437
The present paper reports in vitro strategies for assembly of minicellulosomes with two miniscaffoldins on the Saccharomyces cerevisiae cell surface. It was carried out through incubation of the yeast cells displaying scaffoldins with Escherichia coli lysates containing recombinant cellulases, or using a four-population yeast consortium. The results showed that the display level of miniscaffoldin II was distinctly increased by moving the cellulases production into E. coli or other yeast cells, indicating that the metabolic burden of the yeast host was decreased. The yeast consortium did not show any cellulolytic activity, while the E. coli lysates-treated yeast, whose anchoring miniscaffoldin length was optimized, was able to produce ~1138 mg/L ethanol from microcrystalline cellulose within 4 days. We also confirmed that the yeast-associated minicellulosome moreover showed both higher thermal stability and lower protease accessibility than free minicellulosome. This research promotes the application of S. cerevisiae as a consolidated bioprocessing (CBP) microorganism in cellulosic bioethanol production. 相似文献
163.
164.
Aihong Li Cunhong Pan Linbo Wu Zhengyuan Dai Shimin Zuo Nin Xiao Ling Yu Yuhong Li Xiaoxiang Zhang Wenxia Xue Hongxi Zhang Xuebiao Pan 《Molecular breeding : new strategies in plant improvement》2013,32(1):1-13
Rice black streaked-dwarf virus (RBSDV) disease is recently expanding in southern China and poses a serious threat to rice crops. Few studies related to the genetics and breeding of RBSDV resistance have been reported. We have previously mapped a number of quantitative trait loci (QTLs) for RBSDV resistance by using a recombinant inbred line population of ‘Zhenshan 97’ (ZS97, susceptible)/‘Minghui 63’ (MH63, resistant) with natural infection data in two locations. In the present study, we confirmed the presence of a number of resistant QTLs on chromosomes 6, 7, and 9 from MH63 by using the same population in four different locations. We then focused on a major QTL, qRBSDV-6 MH , on chromosome 6 and introduced it into a highly susceptible japonica rice variety, ‘Huaidao 5’, using MH63 as the donor via marker-assisted selection, to generate seven backcross inbred lines (BILs). Natural infection and artificial inoculation-based tests revealed that all of the BILs had a significantly higher resistance to RBSDV than the recurrent parent. These results demonstrate that qRBSDV-6 MH is a stable major resistance QTL of high breeding value. We also constructed a set of chromosome segment substitution lines (CSSLs) specific to the qRBSDV-6 MH region and these used as fine mapping population. Combining the genotypes of CSSLs with the phenotypes from natural infection data in a highly RBSDV epidemic area during two different sowing seasons, we were able to precisely map qRBSDV-6 MH to the markers S18 and S23 at a physical distance of 627.6 kb on the Nipponbare reference genome. 相似文献
165.
Guihua Jiang Xue Wen Yingwei Qiu Ruibin Zhang Junjing Wang Meng Li Xiaofen Ma Junzhang Tian Ruiwang Huang 《PloS one》2013,8(12)
Neuroimaging studies have shown that heroin addiction is related to abnormalities in widespread local regions and in the functional connectivity of the brain. However, little is known about whether heroin addiction changes the topological organization of whole-brain functional networks. Seventeen heroin-dependent individuals (HDIs) and 15 age-, gender-matched normal controls (NCs) were enrolled, and the resting-state functional magnetic resonance images (RS-fMRI) were acquired from these subjects. We constructed the brain functional networks of HDIs and NCs, and compared the between-group differences in network topological properties using graph theory method. We found that the HDIs showed decreases in the normalized clustering coefficient and in small-worldness compared to the NCs. Furthermore, the HDIs exhibited significantly decreased nodal centralities primarily in regions of cognitive control network, including the bilateral middle cingulate gyrus, left middle frontal gyrus, and right precuneus, but significantly increased nodal centralities primarily in the left hippocampus. The between-group differences in nodal centralities were not corrected by multiple comparisons suggesting these should be considered as an exploratory analysis. Moreover, nodal centralities in the left hippocampus were positively correlated with the duration of heroin addiction. Overall, our results indicated that disruptions occur in the whole-brain functional networks of HDIs, findings which may be helpful in further understanding the mechanisms underlying heroin addiction. 相似文献
166.
Li Wei Tao Xue Hong Yang Guang-Yue Zhao Geng Zhang Zhi-Hong Lu Yan-Hong Huang Xiang-Dong Ma Hai-Xia Liu Sheng-Ru Liang Fang Yang Bi-Liang Chen 《PloS one》2013,8(11)
Objective
To develop an orthotopic, allogeneic, uterine transplantation technique and an effective immunosuppressive protocol in the sheep model.Methods
In this pilot study, 10 sexually mature ewes were subjected to laparotomy and total abdominal hysterectomy with oophorectomy to procure uterus allografts. The cold ischemic time was 60 min. End-to-end vascular anastomosis was performed using continuous, non-interlocking sutures. Complete tissue reperfusion was achieved in all animals within 30 s after the vascular re-anastomosis, without any evidence of arterial or venous thrombosis. The immunosuppressive protocol consisted of tacrolimus, mycophenolate mofetil and methylprednisolone tablets. Graft viability was assessed by transrectal ultrasonography and second-look laparotomy at 2 and 4 weeks, respectively.Results
Viable uterine tissue and vascular patency were observed on transrectal ultrasonography and second-look laparotomy. Histological analysis of the graft tissue (performed in one ewe) revealed normal tissue architecture with a very subtle inflammatory reaction but no edema or stasis.Conclusion
We have developed a modified procedure that allowed us to successfully perform orthotopic, allogeneic, uterine transplantation in sheep, whose uterine and vascular anatomy (apart from the bicornuate uterus) is similar to the human anatomy, making the ovine model excellent for human uterine transplant research. 相似文献167.
IGFBP3, a Transcriptional Target of Homeobox D10, Is Correlated with the Prognosis of Gastric Cancer
Meng Xue Yanfei Fang Guoming Sun Wei Zhuo Jing Zhong Cuijuan Qian Lan Wang Liangjing Wang Jianmin Si Shujie Chen 《PloS one》2013,8(12)
Homeobox D10 (HoxD10) plays important roles in the differentiation of embryonic cells and progression of breast cancer. Our previous report revealed that insulin-like growth factor binding protein-3 (IGFBP3) was regulated by HoxD10 in gastric cancer cells; however, the functional roles and underlying mechanisms of IGFBP3 in gastric cancer remain unclear. Here, we found that the expression of IGFBP3 were upregulated after ectopic expression of HoxD10 in gastric cancer cells. Chromatin immunoprecipitation assay showed that HoxD10 bound to three potential regions of IGFBP3 promoter. Exogenous HoxD10 significantly enhanced the activity of luciferase reporter containing these binding regions in gastric cancer cells. Further data showed that all of these binding sites had Hox binding element “TTAT”. Immunohistochemical staining results revealed that IGFBP3 expression was significantly downregulated in 86 gastric adenocarcinomas tissues relative to their adjacent non-cancerous tissues (p<0.001). Moreover, IGFBP3 expression was significantly lower in gastric tumor with lymph node metastasis compared with that without lymph node metastasis (p=0.045). Patients with high expression level of IGFBP3 showed favorable 5 year overall survival (p=0.011). Knockdown of IGFBP3 accelerated gastric cancer cell migration and invasion and induced the expression of invasive factors including MMP14, uPA and uPAR. Thus, our data suggest that HoxD10-targeted gene IGFBP3 may suppress gastric cancer cell invasion and favors the survival of gastric cancer patients. 相似文献
168.
Yuanliang Xie Mengjie Wang Youjie Zhang Shijun Zhang Aihua Tan Yong Gao Zhengjia Liang Deyi Shi Zhang Huang Haiying Zhang Xiaobo Yang Zheng Lu Chunlei Wu Ming Liao Yu Sun Xue Qin Yanling Hu Li Li Tao Peng Zhixian Li Xiaoli Yang Zengnan Mo 《PloS one》2013,8(7)
Increased serum uric acid (SUA) levels may be involved in the development of non-alcoholic fatty liver disease (NAFLD) in men presenting with metabolic syndrome (MetS) and/or insulin resistance. We aimed to determine the independent relationship between SUA and NAFLD in non-diabetic Chinese male population, and to explore the determinants of SUA levels among indexes of adiposity, lipid, and genotypes pertaining to triglycerides metabolism, inflammation, oxidative stress, and SUA concentrations. A total of 1440 men, classified depending on the presence of ultrasonographically detected NAFLD, underwent a complete healthy checkup program. Genotypes were extracted from our previously established genome-wide association study database. After adjusting for age, smoking, drinking, body mass index, homeostasis model assessment of insulin resistance, C-reactive protein, creatinine, alanine aminotransferase (ALT) and components of metabolic syndrome, the odds ratio for NAFLD, comparing the highest with the lowest SUA quartile, was 2.81 (95% confidence interval 1.66–4.76). A stepwise multivariate linear regression analysis (R2 = 0.238, P<0.001) retained age, waist circumference, serum creatinine, triglycerides, the Q141K variant in ABCG2 (rs2231142) and NAFLD as significant predictors of SUA levels (all P<0.001). Besides, ALT and Met196Arg variant in TNFRSF1B (rs1061622) additionally associated with SUA among individuls with NAFLD. Our data suggest that in Chinese men, elevated SUA is significantly associated with NAFLD, independent of insulin resistance and other metabolic disorders, such as central obesity or hypertriglyceridemia. Meanwhile, among subjects with NAFLD, index of liver damage, such as elevated ALT combined with genetic susceptibility to inflammation associated with increased SUA levels. 相似文献
169.
Purpose
It remains controversial whether mini-incision (MI) benefits patients in total hip arthroplasty (THA). We performed a meta-analysis of randomized controlled trials (RCTs) to assess the effects of MI on surgical and functional outcomes in THA patients.Methods
A systematic electronic literature search (up to May 2013) was conducted to identify RCTs comparing MI with standard incision (SI) THA. The primary outcome measures were surgical and functional outcomes. According to the surgical approach taken, MI THA patients were divided into four subgroups for sub-group meta-analysis. Standardized mean differences (SMDs) or risk differences (RDs) with accompanying 95% confidence intervals (CIs) were calculated and pooled using a fixed-effect or random-effect model according to the heterogeneity.Results
A total of 14 RCTs involving THA 1,174 patients met the inclusion criteria. The trials were medium risk of bias. The overall meta-analysis showed MI THA reduced total blood loss (95% CI, -201.83 to -21.18; p=.02) and length of hospital stay ( 95% CI, -0.67 to -0.08; p=.01) with significant heterogeneity. However, subgroup meta-analysis revealed posterior MI THA had perioperative advantages of reduced surgical duration ( 95% CI, -8.45 to -2.67; P<.001), less blood loss ( 95% CI, -107.20 to -1.73; P=.04) and shorter hospital stay ( 95% CI, -0.74 to -0.06; p=.002) with low heterogeneity. There were no significant differences between MI and SI THA groups in term of pain medication dose, functional outcome (HHS), radiological outcome or complications (P>.05, respectively).Conclusions
Although no definite overall conclusion can be arrived at on whether MI THA is superior to SI THA, posterior MI THA clearly result in a significant decrease in surgical duration, blood loss and hospital stay. It seems to be a safe minimally invasive surgical procedure without increasing the risk of component malposition or complications. 相似文献170.
Yu Chen Huadan Xue Zheng-yu Jin Jie Zhang Hao Sun Xuan Wang Zhu-hua Zhang Da-ming Zhang Guang-ming Lu Zhao-qi Zhang U. Joseph Schoepf Andreas M. Bucher Christopher D. Wolla Yun Wang 《PloS one》2013,8(11)