2.Study of Breeding Saccharomyces cerevisiae with Improved Temperature and Ethanol Tolerance by Genome Shuffling
Hao WANG ; Hang WANG ; Chun MENG ; Yang-Hao GUO ;
Microbiology 1992;0(04):-
By UV induced mutagenesis of protoplasts of Saccharomyces cerevisiae strain f4, f5 and f6, and screening on plates containing different concertration of ethanol at different temperature, we obtained improved strains, such as f4.2, f5.1, f6.2, f4.5. By using a DES to deal with all the improved strains, We obtained two mutants, f5.1.1 and f4.2.1,which have improved ethanol torlerance. We made use of genome shuffling to generate improved strains in this work. We shuffled twice these improved strains by protoplast fusion and finally obtained strains with higher temperature and ethanol tolerance. we also identified shuffled strains that produced more ethanol by shake-flask experments. At the 35℃, the ethanol yield of R24 strain got to 12.93% (W/V), and were almost 5% higher than that of stain f4.
4.Clinical analysis of 109 cases of isolated fetal pyelectasis and pregnancy outcome
Hao ZHU ; Chun SHEN ; Xiaotian LI
Chinese Journal of Perinatal Medicine 2015;18(9):683-686
Objective To investigate the prognosis of isolated fetal pyelectasis detected by ultrasound.Methods A total of 109 cases of isolated fetal pyelectasis (renal pelvis anteroposterior diameter ≥ 5 mm by ultrasound screening at any gestational age without structural or chromosome abnormalities) detected by prenatal ultrasound screening from March 2004 to July 2014 in Obstetrics & Gynecology Hospital of Fudan University,were delivered and followed up until neonatal period on chromosome examination,prenatal B ultrasound and outcome of neonates.Receiver operating characteristics curves were plotted and used to predict the optimal critical point of poor prognosis and the warning point of follow-up.Results Among the 109 cases,83 cases tended to have a natural recovery during pregnancy,71 of them had normal renal pelvis.Two of the neonates died,9 cases needed surgical treatment,and 98 cases had normal renal pelvis or need follow-up only.The area under the receiver operating characteristics curves was 0.860 (95%CI:0.860± 1.96 × 0.112).The optimal critical point of poor prognosis was determined at ≥ 11 mm in anteroposterior diameter with sensitivity 81.8%,and specificity 83.7%,and the warning point of prenatal follow-up was at ≥ 7 mm in anteroposterior diameter with sensitivity 100.0% and specificity 50.0%.Conclusions The prognosis of isolated fetal pyelectasis is mostly good.The fetus with pyelectasis thicker than 7 mm should be followed-up closely during prenatal and neonatal period,and the fetus with pyelectasis thicker than 11 mm is likely to have poor prognosis in neonatal period.
5.Silencing of miR-21 influences the function of colon cancer cell line HT-29 and the expression of PDCD4
Yupeng REN ; Chun SONG ; Hao ZHANG
China Oncology 2015;(1):6-12
Background and purpose: PDCD4 may be inhibited by miR-21 to regulate the malignant behaviors of colon cancer such as invasion and migration. This study aimed to explore the function of colon cancer HT-29 cell lines by downregulating miR-21 expression and discuss the mechanisms and relationship between miR-21 and PDCD4 in colon cancer malignant behaviors. Methods:simiR-21 was transfected into colon cancer cell line HT-29 to downregulate the expression of miR-21. Proliferation, apoptosis, migration and invasion were detected by MTT, flow cytometry and Transwell assay after transfection. PDCD4 expression was detected by Western blot and qRT-PCR. Results:The qRT-PCR analysis result proved that the transfection efifciency was 60%-65%. MTT analysis result showed that the proliferations of HT-29 cells were inhibited after the transfection of miR-21 for 72, 96, 120 h (t=1.276, P<0.05;t=3.276, P<0.01;t=4.523, P<0.01). Comparing with si-negative control and miR-21 groups, lfow cytometry result showed that the apoptosis rate was increased after miR-21 expression downregulated (t=2.132, P<0.05;t=3.524, P<0.05). Transwell assay result showed that migration (t=2.423, P<0.05; t=3.153, P<0.05) and invasion(t=3.245, P<0.05; t=5.236, P<0.05) were inhibited;Western blot result showed that PDCD4 expression was up-regulated at protein level(t=2.342, P<0.05;t=4.215, P<0.05);qRT-PCR result showed that PDCD4 expression was up-regulated at mRNA level(t=2.261, P<0.05; t=3.492, P<0.05). Conclusion: The proliferation, migration and invasion are the inhibited, and apoptosis is attenuated after miR-21 downregulated by simiR-21 transfection, PDCD4 expression is up-regulated. miR-21 may enhance the malignant behavior of cancer cells by downregulating the PDCD4 expression, miR-21 might be a target gene for colon cancer therapy.
7.MeaSurement of Relative Affinity and Specificity of Monoclonal Antibodies
Chun-Hai HAO ; Yuan-Yao CHEN ;
Chinese Journal of Immunology 1985;0(05):-
To measure the relative affinity and type Specificity of neutralizing monoclonal antibodies against the hexon antigen of adenovirus type 7,a simple ELISA double antibody binding system has been developed.By this method,ralative affinity of nine MAbs was estimated from the antibody concentrations at approximately 50% of plateau binding and were ranked.The theoretical basis for this method was discussed. Hybridomas secreting antibodies of desired affinity can be selected at an early stage after fussion by measuring relative affinity of hybridomas supernatants.The type specificity was judged by the difference between end-point concentration against adeno- virus type 7 and type 3.And the relation between affinity and specificity of MAbs was discussed.
9.Establishment of a rat model of atrioventricular block by chemical ablation
Xuemei WANG ; Mei MA ; Chun ZHANG ; Xi SHOU ; Hao WEN
Journal of Medical Postgraduates 2014;(4):378-381
Objective Preparation of a stable and reliable atrioventricular blockage ( AVB) animal model is of great im-portance to anti-arrhythmic drugs and biological engineering research .The aim of the article was to establish a rat model of AVB in-duced by chemical ablation, providing an effective animal model for the development of new drugs . Methods 60 adult SD rats were randomly divided into 4 groups(n=15): normal saline (NS) group, Verapmil (Ver) group, chemical ablation group 1 and chemical ablation group 2.0.9%NaCl (5 mg/kg) was injected into caudal vein of each rat in NS group .Verapmil (5 mg/kg) was injected into the caudal vein in Ver group.Anhydrous ethanol(50μL)was injected into atrioventricular groove area in chemical abla-tion group 1.Anhydrous ethanol(50μL) was injected into atrioventricular node area in chemical ablation group 2.The electrocardio-grams of the rats were examined by electrophysiological recorder.HE staining and Connexin 43 (CX43) immunohistochemical tech-nique were applied to atrioventricular junctions of the rats . Results A rat model of AVB was successfully established .Compared with NS group([45 ±2.24]per field of view), there was a significant decrease in the CX43 expressions of chemical ablation group 1 and group 2 ([15.20 ±2.23]per field of view, [22.10 ±4.70]per field of view)(P<0.05).Concerning NS group and Ver group, myocyte tissues of the atrioventricular nodal region were detected to remain in order without obvious changes and the expres-sion of CX43 immunoreactive protein was obvious under light microscope.As to chemical ablation group 1 and group 2, myocyte tissues were in degenerative necrosis and the expression of CX43 im-munoreactive protein was in lighter staining.Compared with Ver group, the incidence rate(73.3%, 60.6%) and the mortality rate (33.3%, 26.7%)of third-degree AVB decreased remarkably(P<0.05). Conclusion Chemical ablation can be induced to estab-lish a stable and reliable rat model of AVB , providing an effective
animal model for the research and development of new anti-arrhythmic drugs.
10.Effects of SPARC on expression of TGF-βl and collagen type Ⅰ in keloid fibroblasts
Chun WANG ; Xiaojing LI ; Chaohua LIU ; Xiaojuan WENG ; Dongyue HAO
Chinese Journal of Medical Aesthetics and Cosmetology 2011;17(5):377-380
Objective To observe the effects of secreted protein,acidic and rich in cysteine (SPARC) on the expression of TGF-β1 and collagen type Ⅰ in cultured human keloid fibroblasts by real-time fluorescence quantitative RT-PCR.Methods In vitro keloid fibroblasts were stimulated by different concentrations of recombinant human SPARC,and with the control group for comparison,real-time fluorescence quantitative RT-PCR to detect expression of TGFβ1 and collagen type Ⅰ.Results Compared with the control group,the expression of TGF-β1 and collagen type Ⅰ was significantly increased in the experimental group.Conclusions SPARC could enhance the expression of TGF-β1 and collagen type Ⅰ in keloid fibroblasts significantly.