1.Preparation of liposomal pemetrexed and its effects on breast cancer
Fang BAI ; Ting CHEN ; Yan LIU ; Kejin WU ; Qing CHEN ; Yunshu LU ; Meixin GE
Journal of Shanghai Jiaotong University(Medical Science) 2017;37(2):190-192
Objective · To prepare the liposomal pemetrexed and investigate its effects on MCF-7 breast cancer cells in vitro and nude mice bearing MCF-7 xenograft tumors. Methods · Liposomal pemetrexed was prepared by film dispersion method. Inhibition of MCF-7 breast cancer cell lines was evaluated by CCK-8 method, and anti-tumor effects were investigated on Balb/c nude mice bearing MCF-7 xenograft tumors. Results · Liposomal pemetrexed inhibited the growth of MCF-7 cells. When the concentrations of pemetrexed were 0.20, 0.40 and 10.00 μg/mL, the cell viability in experiment group (liposomal pemetrexed) was significantly lower than that in control group (pemetrexed of same concentration gradient), with P values of 0.013, 0.035 and 0.041, respectively. Compared with blank group (same volume of PBS), the volumes and weights of tumors of nude mice in experiment group(liposomal pemetrexed) and control group (same volume of pemetrexed) were significantly lower, and the volume and weight of tumor in experiment group were also significantly lower than those in control group (P=0.000). Conclusion · Compared to bulk drug of pemetrexed, liposomal pemetrexed can inhibit the growth of MCF-7 breast cancer cells and the Balb/c nude mice bearing MCF-7 xenograft tumors.
2.The Effects of Dilute Acid Hydrolysate By-products of Corn Stover on Ethanol Fermentation of Xylose-utilising Saccharomyces cerevisiae 6508-127
Bei LIN ; Xin-Qing ZHAO ; Xu-Meng GE ; Feng-Wu BAI ;
China Biotechnology 2006;0(07):-
During the dilute acid pretreatment of lignocellulosic materials such as corn stover, hemicellulose is hydrolyzed into monosaccharides, and meanwhile, toxic by-products are simultaneously generated, which may influence ethanol fermentation thereafter. Studies on the inhibitory effects of the by-products on ethanol fermentation are of practical use for further improvement of ethanol yield from lignocellulosic materials. Five by-products, including acetic acid, formic acid, vanillin, furfural and 5-hydroxymethylfurfural, were identified to be the main components in the hydrolysate of dilute acid pretreatment of local corn stover, which were added into the medium at different concentrations to study their impacts on the growth and ethanol fermentation of a recombinant xylose-utilizing yeast strain, S. cerevisiae 6508-127. The ethanol production was inhibited by formic acid and acetic acid to a lesser extent than that to the growth, and formic acid was shown to be much more toxic than acetic acid, showing severe inhibitory effects at the concentration of 1g/L, half of the concentration for acetic acid which showed remarkably negative effects on ethanol fermentation. Vanillin caused a much longer lag-phase in growth when the concentration was 2g/L, and the lag-phase was not obvious at lower concentrations. At the concentration of 6g/L, vanillin completely inhibited the fermentation as well as the cell growth. 5-Hydroxymethylfurfural was showed to remarkably inhibit ethanol production, but the biomass yield was higher by exogenous addition of 5-Hydroxymethylfurfural than control. Furfural at 0.5~1.5g/L inhibited the cell growth, but the ethanol yield was higher than that of the control experiment. It was also found that vanillin, furfural and 5-hydroxymethylfurfural could be assimilated and metabolized by S. cerevisiae 6508-127 under the experimental conditions.
3.Predictive effect of back propagation neural network model on hematoma enlargement in patients with cerebral hemorrhage
Gang WU ; Guoyu XU ; Ying BAI ; Qing ZHOU ; Ce LIU ; Pengfei CHANG
Chinese Journal of Cerebrovascular Diseases 2015;(10):505-510
Objective To study predicting results of the back propagation (BP)neural network model for hematoma enlargement (HE)in patients with intracerebral hemorrhage. Methods The clinical data of 128 patients with cerebral hemorrhage admitted to the 309th hospital of People′s Liberation Army from January 2011 to December 2014 were analyzed retrospectively. The Matlab 7. 14 software was used to achieve BP neural network model for predicting hematoma enlargement within 24 hours in patients with intracerebral hemorrhage (HE ≥6. 0 ml and HE ≥12. 5 ml). The mean square error (MSE)of the model and the accuracy of the overall prediction were calculated. The receiver operation characteristic (ROC) curve was drawn for predicting HE. Results When the BP neural network predicted HE ≥6. 0 ml and HE ≥12. 5 ml,the mean square deviations of the training set,validation set,and test set were 0. 061, 0. 143,0. 052 and 0. 023,0. 057,and 0. 065,respectively. The best fitting performance verification of hematoma enlargement was as follows:≥ 6. 0 ml for network training 11 times and the error value 0. 224;≥12. 5 ml for network training 20 times,and the error value 0. 057. The overall accuracies of predicting HE ≥6. 0 ml and HE ≥12. 5 ml were 92. 2% (118/ 128)and 96. 9% (124/ 128)respectively. Conclusion The BP neural network model have no special limitation for data. It can accurately fit the hematoma expansion model of cerebral hemorrhage.
4.Challenges and countermeasures to the clinical teaching of oncology
Renhua WU ; Wanping TANG ; Juan BAI ; Yi QING
Chinese Journal of Medical Education Research 2020;19(10):1154-1158
Aiming at the contradiction between the current oncology teaching model and the rapid development of modern oncology, this study proposes to use precision medicine principles, integrated medicine (MDT treatment) and problem-based, evidence-based CSCO guide learning in clinical oncology teaching. Through specific cases, students are instructed to study the guidelines, and cultivate students' concepts of evidence-based medicine, students' interest in participating in oncology teaching, and they can initially form treatment strategies. The prospects have been put forward from the establishment of a clinical oncology curriculum system, the construction of a single-disease diagnosis and treatment teaching environment and a team of teaching staff, the reinforcement of students' basic experiments and evidence-based clinical data cross-application learning, and the enhancement of humanistic quality education.
5.Agroinfiltration, a useful technique in plant molecular biology research.
Zhao-Ming LIU ; Zong-Zhi LIU ; Qing-Wu BAI ; Rong-Xiang FANG
Chinese Journal of Biotechnology 2002;18(4):411-414
Agroinfiltration is a newly developed plant transient gene expression technique, which is simple, rapid and reproducible. It has been widely used in analyses of foreign gene expression, hypersensitive reaction, gene silencing, promoter activity and identification of new disease-resistance genes. In this paper, we describe the principle and the operation procedure of Agroinfiltration and its application in diverse aspects of plant molecular biology research. Our experiences in modification of the Agroinfiltration technique are also provided.
Agrobacterium tumefaciens
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genetics
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Genetic Vectors
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genetics
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Plants
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genetics
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Plants, Genetically Modified
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Research Design
6.Breeding of Yeast Fusant for Efficient Ethanol Fermentation from Xylose
Jie LI ; Fan LI ; Chen-Guang LIU ; Jian-Gang REN ; Xin-Qing ZHAO ; Xue-Meng GE ; Feng-Wu BAI ;
China Biotechnology 2006;0(06):-
Yeast strains with improved ethanol yield are important for efficient bioconversion of lignocellulosic biomass for fuel ethanol.Candida shehatae CICC1766 was adapted to 4%(v/v)ethanol,and then subjected to UV mutagenesis.One respiration deficient mutant Rd-5 with improved xylose fermentation capability was selected.Protoplasts of Rd-5 were inactivated by UV treatment,followed by the PEG-mediated protoplast fusion with a Saccharomyces cerevisiae strain with good ethanol-fermenting capability.The xylose fermenting capability of the fusants was investigated,and the fusant F6 demonstrated good ethanol fermentation performance,producing 18.75g/L ethanol from 50g/L xylose with an ethanol yield of 0.375 or 73.4% of its theoretical value of 0.511.Comparing with its parent Candida shehatae strain,the ethanol yield of F6 was increased by 28%.
7.Adaptive Evolution of cry Genes in Bacillus thuringiensis:Implications for Their Specificity Determination
Wu JIN-YU ; Zhao FANG-QING ; Bai JIE ; Deng GANG ; Qin SONG ; Bao QI-YU
Genomics, Proteomics & Bioinformatics 2007;5(2):102-110
The cry gene family, produced during the late exponential phase of growth in Bacillus thuringiensis, is a large, still-growing family of homologous genes, in which each gene encodes a protein with strong specific activity against only one or a few insect species. Extensive studies are mostly focusing on the structural and functional relationships of Cry proteins, and have revealed several residues or domains that are important for the target recognition and receptor attachment. In this study,we have employed a maximum likelihood method to detect evidence of adaptive evolution in Cry proteins, and have identified 24 positively selected residues, which are all located in Domain Ⅱ or Ⅲ. Combined with known data from mutagenesis studies, the majority of these residues, at the molecular level, contribute much to the insect specificity determination. We postulate that the potential pressures driving the diversification of Cry proteins may be in an attempt to adapt for the "arm race" between δ-endotoxins and the targeted insects, or to enlarge their target spectra, hence result in the functional divergence. The sites identified to be under positive selection would provide targets for further structural and functional analyses on Cry proteins.
8.Influence on the adhesion and growth of dermal papilla cells by chondroitin sulfate and heparin sulfate
Bo CHENG ; Jin-Jin WU ; Yue MAI ; Rong-Qing LIU ; Bai-Yu ZHONG ; Shu-Qian TANG
Journal of Third Military Medical University 2001;23(4):451-453
Objective To investigate the actions of extra cellular medium in growth and differentiation of hair follicle and to look for growth adjusting factors for dermal papilla cells (DPC). Methods Dermal papilla cells were isolated and cultivated with two steps method and the cells were identified by immunohistochemical staining for actin. Influence was examined on the adhesion and growth of dermal papilla cells by chondroitin sulfate A, chondroitin sulfate C and heparin sulfate. Results Two steps method of enzyme digestion for isolating and cultivating dermal papilla cells was an efficient method and large amount of dermal papilla of high purity were harvested with this method. The method is very simple and easy to manege with. Increased adhesion and growth of dermal papilla cells were observed in specimen treated with chondroitin A and heparin sulfate. No significant effects was observed in the cells treated with chondroit in sulfate C. Conclusion Some extra cellular medium can regulate the adhesion and growth of dermal papilla cells and therefore influence the growth and development of hair follicle.
9.On-site assessment on the definition and classification of suspected cases in the manual of WHO Japanese Encephalitis Surveillance Standards
Xiao-Qiang QIU ; Bai-Qing DONG ; Jin-Ye YANG ; Mei LIN ; Yi TAN ; Xing-Hua WU ; Yi-Xing LI ; Hadler STEPHEN
Chinese Journal of Epidemiology 2011;32(1):38-41
Objective To assess the new edition of WHO Japanese Encephalitis (JE) Surveillance Standards (WHO Standards) based on syndrome surveillance data and to provide field evidence regarding the standards. Methods Based on syndrome surveillance data, acute encephalitis syndrome (AES) case was categorized, according to the WHO Standards. A cohort study was applied to estimate the AES definition set in the Standard and relative risk was computed to estimate the existence and intensity of statistical correlation between AES and JE cases. Percentage of attributable risk was counted to describe the coverage of AES for JE cases in the studied population. Sensitivity,specificity, Youden index and positive predictive value of AES components were calculated for the purpose of identifying the clinical values under the screening program. Results 1424 suspected cases were evaluated in the surveillance program and 1396 cases with ELISA result, of which 109 positive cases were detected. According to the "standardized" classification, a total of 706 cases in line with AES case deftuition, were categorized into 83 cases of JE, 425 cases of AES unknown and 198 cases of AES other agent. In the cohort study,a relative risk of 4.62 (95% CI:2.80-7.63 ) and the percentage of attributable risk as 78.35% (95% CI: 64.25% -86.89% ) were observed. Conclusion The AES definition for JE was significantly effecting on the screening programs and a strong correlation strength was observed in the study. AES syndrome could cover most of the JE cases. "Convulsions",with appreciative screening value, was recommended to be involved into the new version of the WHO Standards.
10.Factors related to collagen gel contraction in hair follicle organotypic culture.
Zhong-fa LU ; Jin-jin WU ; Rong-qing LIU ; Bai-yu ZHONG ; Min ZHENG
Journal of Zhejiang University. Medical sciences 2003;32(4):323-326
OBJECTIVETo investigate the effects of rat tail collagen, hair follicle dermal papilla cells and hair follicle epithelium cells on collagen gel contraction in organotypic culture.
METHODSThe hair follicle organotypic culture was prepared with different concentrations of rat tail collagen, different number of dermal papilla cells and hair follicle epithelium cells in DMEM medium, after cultured for 10 days the diameter of collagen gel was measured.
RESULTThe concentration of rat tail collagen, hair follicle dermal papilla cells and hair follicle epithelium cells significantly influenced on collagen gel contraction in organotypic culture (P<0.01). The contraction of collagen gel was negatively related to the concentration of rat tail collagen, while the concentration of dermal papilla cells and hair follicle epithelium cells was positively related to the contraction of collagen gel.
CONCLUSIONThe key factor influencing collagen gel contraction in organotypic culture is the concentration of rat tail collagen, hair follicle dermal papilla cells and hair follicle epithelium cells.
Animals ; Cell Division ; Cells, Cultured ; Collagen ; physiology ; Gels ; Hair Follicle ; cytology ; Rats