|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Morphological and functional changes of mitochondria in apoptotic esophageal carcinoma cells induced by arsenic trioxide显示文摘AIM:To demonstrate that mitochondrial morphological andfunctional changes are an important intermediate link in thecourse of apoptosis in esophageal carcinoma calls inducedby As_2O_3.METHODS:The esophageal carcinoma call line SHEEC1,established in our laboratory,was cultured in 199 growthmedium,supplemented with 100mL·L^(-1)calf serum and3 mol·L^(-1)As_2O_3(the same below).After 2,4,6,12,24 hof drug adding,the SHEECl calls were collected for light-and electron-microscopic examination.The mitochondriawere labeled by Rhodamine fluorescence probe and thefluorescence intensity of the mitochondria was measured byflow cytorneter and cytofluorimetric analysis.Further,themitochondrial transmembrane potential(MTP,ΔΨm)change was also calculated.RESULTS:The mitochondrial morphological change afteradding As_2O_3 could be divided into three stages.In theearly-stage(2-6h)after adding As203,an adaptiveproliferation of mitochondria appeared;in the mid-stage(6-12 h)a degenerative change was observed;and in the late-stage(12-24 h)the mitochondria swelled with outermembrane broken down and then calls death with apoptoticchanges of nucleus.The functional change of themitochondria indicated by fluorescent intensity,whichreflected the MTP status of mitochondria,was in accordancewith morphological change of the mitochondria.Thefluorescent intensity increased at early-stage,decUned inmid-stage and decreased to the lowest in the late-stage.24h after As_2O_3 adding,the cell nucleus showed typicalapoptotic changes.CONCLUSION:Under the inducement of As_2O_3,the earlyapoptotic changes of SHEEC1 cells ware the apparentmorphological and functional changes of mitochondria,afterwards the nucleus changes followed.It is consideredthat changes of mitochondria are an important intermediatelink in the course of apoptosis of esophageal carcinoma cells induced by As_2O_3. | Zhong-Ying Shen Jian Shen Qiao-Shan Li Department of Pathology,Medical College of Shantou University,Shantou 515031,Guandong Province,China Cai-Yun Chen Central Lab.Medical College of Shantou University Jiong-Yu Chen Central Lab.of Tumor Hospital,Medical College of Shantou University Yi Zeng Institute of Virology,Chinese Academy of Preventive Medicine,Beijing 100052,China | 2002 | World Journal of Gastroenterology2002，8，1： | 35 |
| 2 | Telomere and telomerase in the initial stage of immortalization of esophageal epithelial cell显示文摘AIM: To search for the biomarker of cellular immortalization,the telomere length, telomerase activity and its subunits incultured epithelial cells of human fetal esophagus in theprocess of immortalization.METHODS: The transgenic cell line of human fetalesophageal epithelium (SHEE) was established with E6 E7genes of bt man papillomavirus (HPV) type 18 in ourlaboratory. Morphological phenotype of cultured SHEE cellsfrom the 6th to 30th passages, was examined by phasecontrast microscopy, the telomere length was assayed bySouthern blot method, and the activity of telomerase wasanalyzed by telomeric repeat amplification protocol (TRAP).Expressions of subunits of telomerase, hTR and hTERT,were assessed by RT-PCR. DNA content in cell cycle wasdetected by flow cytometry. The cell apoptosis wasexamined by electron microscopy (EM) and TUNEL label.RESULTS: SHEE cells from the 6 th to 10 th passagesshowed cellular proliferation with a good differentiation.From the 12 th to the 16 th passages, many senescent andapoptotic cells appeared, and the telomere length sharplyshortened from 23 kb to 17 kb without expression of hTERTand telornerase activity. At the 20 th passage, SHEE cellsovercame the senescence and apoptosis and restored theirproliferative activity with expression of telomerase andhTERT at low levels, but the telomere length shortenedcontinuously to the lowest of 3 kb. After the 30 th passagecells proliferation was restored by increment of cells at S andG2M phase in the cell cycle end telomerase activity expressedat high levels and with maintenance of telomere length.CONCLUSION: At the early stage of SHEE cells, telomeresare shortened without expression of telomerase and hTERTcausing cellular senescence and cell death. From the 20 thto the 30 th passages, the activation of telomerase andmaintenance of telomere length show a progressive processfor immortalization of esophageal epithelial cells. Theexpression of telomerase may constitute a biomarker fordetection of immortalization of cells. | Zhong-Ying Shen Li-Yan Xu Wei-Jia Cai Min-Hua Chen Jian Shen,Department of Tumor Pathology,Medical College of Shantou University,Shantou 515031,Guangdong Province,China En-Min Li,Department of Biochemistry and Molecular Biology,Medical College of Shantou University,Shantou 515031,Guangdong Province,China Yi Zeng,Institute of Virology,Chinese Academy of Preventive Medicine,Beijing 100052,China | 2002 | World Journal of Gastroenterology2002，8，2： | 21 |
| 3 | Overexpression of p27^(KIP1)induced cell cycle arrest in G_1 phase and subsequent apoptosis in HCC-9204 cell line显示文摘AIM We have previously reported that inducibleover-expression of Bak may prolong cell cycle inG1 phase and lead to apoptosis in HCC-9204 cells.This study is to investigate whether p27KIP1playsan important role in this process.METHODS In order to elucidate the exactfunction of p27KIP1in this process,a zinc induciblep27KIP1stable transfectant and transient p27KIP1-GFP fusion transfectant were constructed.Theeffects of inducible,p27KIP1on cell growth,cellcycle arrest and apoptosis were examined in themock,control pMD vector,and pMD-KIP1transfected HCC-9204 cells.RESULTS This p27KIP1-GFP transfectant maytransiently express the fusion gene.The cellgrowth was reduced by 35% at 48 h of p27KIP1induction with zinc treatment as determined bytrypan blue exclusion assay.These differencesremained the same after 72 h of p27KIP1expression,p27KIP1caused cell cycle arrest after24 h of induction,with 40% increase in G1population.Prolonged p27KIP1expression in thiscell line induced apoptotic cell death reflected byTUNEL assay.Fourty-eight h and 72 h of p27KIP1expression showed a characteristic DNA ladder onagarose gel electrophoresis. CONCLUSION Bak may induce cell cycle arrest inG1 phase through upregulating expression ofp27KIP1and subsequently lead to apoptosis inHCC-9204 cells.The p27KIP1-GFP fusion proteincan be transiently expressed in HCC-9204 cells.The inducible p27KIP1-expressing cell line providesa model to assess p27KIP1function. | Jiang Li Xin Ke Yang Xin Xin Yu Meng Liang Ge Wen Liang Wang Jie Zhang Yun De Hou Department of Pathology,Fourth Military Medical University,Xi’an 710033,Shaanxi Province,China State Key Laboratory for Molecular Virology and Genetic Engineering,Beijing 100052,China Department of Dermatology,Beijing Hospital,Beijing 100016,China Institute of Radiation Medicine,Beijing 100085,China | 2000 | World Journal of Gastroenterology2000，6，4： | 20 |
| 4 | Detection of anti-preS1 antibodies for recovery of hepatitis B patients by immunoassay显示文摘AIM: To establish a convenient immuncassay method based on recombinant antigen preS1(21-1l9aa) to detect anti-preS1antibodies and evaluate the clinical significance of antibodies in hepatitis B.METHODS: The expression plasmid pET-28a-preS1 wasconstructed, and a large quantity of preS1 (21-119aa)fragment of the large HBsAg protein was obtained. ThepreS1 fragment purified by Ni2+ -IDA affinity chromatographywas used as coated antigen to establish the indirect ELISAbased on streptavidin-biotin system for detection of the anti-preS1 antibodies in sera from HBV-infected patients. Forfollow-up study, serial sera were collected during theclinical course of 21 HBV-infected patients and anti-preS1antibodies, preS1 antigen, HBV-DNA and other serologicalHBV markers were analyzed.RESULTS: preS1 (21-119aa) fragment was highly expressedfrom the plasmid pET-28a-preS1 in a soluble form in E. Coli(30 rog@ L-1 ), and easily purified to high purity over 90 % byone step of Ni2+ -IDA-sepharose 6B affinity chromatography.The purity and antigenicity of the purified preS1 (21-119aa)protein was determined by 150 g@ L-1 SDS-PAGE, Westemblot and a direct ELISA. Recombinant preS1 (21-119aa)protein was successfully applied in the immunoessay whichcould sensitively detect the anti-preS1 antibodies in serumspecimens of acute or chronic hepatitis B patients. Resultsshowed that more than half of 19 acute hepatitis B patientsproduced anti-preS1 antibodies during recovery of thedisease, however, the response was only found in a few ofchronic patients. In the clinical follow-up study of 11patients with anti-preS1 positive serological profile, HBsAgand HBV-DNA clearance occurred in 6 of 10 acute hepatitis Bpatients in 5-6 months, and seroconversion of HBeAg anddisappearance of HBV-DNA occurred in 1 chronic patientstreated with lavumidine, a antiviral agent.CONCLUSION: The high-purity preS1 ( 21-119aa) coatedantigen was successfully prepared by gene expression andaffinity chromatography. Using this antigen, a convenientlydetective system of anti-preS1 antibodies in sero wasestablished. Preliminarily clinical trial the occurrence of anti-preSl antibodies in acute hepatitis B patients suggests theclearance of HBV from serum in a short-term time, and anti-preS1 positive in chronic patients means health improvementor recovery from the disease. | Jun Wei Guang-Di Li Yuan Wang Zu-Chuan Zhang,Institute of Biochemsitry and Cell Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China Yu-Qin Wang Zhi-Meng Lu,Department of Clinical virology,Rui-Jin Hospital,Shanghai Second Medical University 200025,Shanghai,China | 2002 | World Journal of Gastroenterology2002，8，2： | 15 |
| 5 | Generation of a recombinant herpes simplex virus which can provide packaging function for recombinant adeno-associated virus显示文摘The generation of a recombinant HSV (rHSV) that can provide packaging function for rAAV production is described. A set of cosmids including cos48, cos28, cos6, cos14 and cos56, which represents the HSV-1 genome was used for generation of this rHSV. Rep and cap genes of AAV-2 were inserted into Xba Ⅰ site of UL2 gene on cos6, generating cos6-rcΔUL2. After being digested with Pac Ⅰ , cos6-rcΔUL2 and the other 4 cosmids were cotrans-fected into BHK-21 cells. The recombinant virus HSV1-rc/ΔUL2 carrying rep and cap genes was generated due to the homologous recombination of the 5 cosmids. The results showed that the existence of rep and cap genes on this rHSV was stable from passage to passage and the rHSV could support the packaging of rAAV either in cells transiently transfected with AAV vector or in stable cell line harboring AAV vector. Further modification of this rHSV and optimization of conditions involved in rAAV preparation may lead to a large-scale production of rAAV in the near future. | WU Zhijian, WU Xiaobing and HOU YundeState Key Laboratory for Molecular Virology and Genetic Engineering , Institute of Virology , Chinese Academy of Preventive Medicine , Beijing 100052, China Corresponding author | 1999 | Chinese Science Bulletin1999，44，8： | 15 |
| 6 | Cross-reactivity of hypervariable region 1 chimera of hepatitis C virus显示文摘AIM: To analyze the amino acid sequences of hypervariable region 1 (HVR1) of HCV isolates in China and to construct a combinatorial chimeric HVR1 protein having a very broad high cross-reactivity.
METHODS: All of the published HVR1 sequences from China were collected and processed with a computer program.Several representative HVR1's sequences were formulated based on a consensus profile and homology within certain subdivision. A few reported HVR1 mimotope sequences were also included for a broader representation. All of them were cloned and expressed in E.coli. The cross-reactivity of the purified recombinant HVR1 antigens was tested by ELISA with a panel of sera from HCV infected patients in China.Some of them were further ligated together to form a combinatorial HVR1 chimera.
RESULTS: Altogether 12 HVR1s were selected and expressed in E. coli and purified to homogeneity. All of these purified antigens showed some cross-reactivity with sera in a 27 HCV positive panel. Recombinant HVR1s of No. 1, 2, 4, and 8# showing broad cross-reactivities and complementarity with each other, were selected for the ligation elements. The chimera containing these 4 HVR1s was highly expressed in E. coli. The purified chimeric antigen could react not only with all the HCV antibody positive sera in the panel but also with 90/91 sera of HCV -infected patients.
CONCLUSION: The chimeric antigen was shown to have a broad cross-reactivity. It may be helpful for solving the problem caused by high variability of HCV, and in the efforts for a novel vaccine against the virus. | Bing-Shui Xiu Shi-Gan Ling Xiao-Guo Song He-Qiu Zhang Kun Chen Cui-Xia Zhu Laboratory of Molecular Virology,Institute of Basic Medical Sciences,Academy of Military Medical Sciences,Beijing 100850,China | 2003 | World Journal of Gastroenterology2003，9，6： | 11 |
| 7 | Human papillomavirus DNA and P16~(INK4A) expression in concurrent esophageal and gastric cardia cancers显示文摘AIM:To investigate the relationship between human papillomavirus (HPV) infection and concurrent esophagus and gastric cardia cancer from the same patient (CC) and examine the significance of P16 INK4A protein expression.METHODS:Polymerase chain reaction was used to detect the presence of HPV type16 (HPV16).The expression of P16 INK4A protein was detected using immunohistochemistry.RESULTS:Among the CC specimens,HPV16-DNA was found in eight cases of esophageal squamous cell carcinoma (ESCC) and five cases of gastric cardia adenocarcinoma (GCA),respectively (47% vs 29%),and two of both ESCC and GCA.P16 INK4A was highly expressed in both ESCC and GCA.In the HPV-associated positive CC,higher P16 INK4A expression was observed in the GCA than in the ESCC (75% vs 25%,P < 0.05).CONCLUSION:HPV16 as a correlated risk factor may play an important role in the development of ESCC and GCA.P16 INK4A may be a screening index in the HPVassociated carcinoma of gastric cardia. | Guang-Cheng Ding,Tao Guo,Department of Gastroenterology,The First Affiliated Hospital and The Fifth Affiliated Hospital,Zhengzhou University,Zhengzhou 450052,Henan Province,China Jing-Li Ren,Xin Song,Sheng-Li Zhou,Zong-Min Fan,LiDong Wang,Henan Key Laboratory for Esophageal Cancer Research,Department of Gastroenterology,The First Affiliated Hospital,College of Basic Medicine,Zhengzhou University,Zhengzhou 450052,Henan Province,China Fu-Bao Chang,Department of Thoracic Surgery,Linzhou Center Hospital,Linzhou 456500,Henan Province,China Ji-Lin Li,Department of Pathology,Yaocun Esophageal Cancer Hospital,Linzhou 456500,Henan Province,China Ling Yuan,Department of Oncoradiotherapy,Henan Province Tumor Hospital,Zhengzhou 450003,Henan Province,China Yi Zeng,Institute of Virology,Chinese Academy of Preventive Medicine,Beijing 100052,China | 2010 | World Journal of Gastroenterology2010，16，46： | 11 |
| 8 | Effects of HBV gene variations on disease development and antiviral therapy for patients with chronic hepatitis B显示文摘Viral variation may change pathogenicity, escape immunity, lead to persistence infection, and cause drug resistance against antiviral therapy. This study was undertaken to investigate the effects of HBV gene variation on the progression of disease and on the efficacy of antiviral therapy for patients with chronic hepatitis B(CHB). METHODS:Hepatitis B virus (HBV) gene mutational sites were detected using gene chip in selected hepatitis B patients. RESULTS:In the patients HBeAg did not show serologic conversion or HBeAg(-)/anti-HBe(+), but their HBV DNA remained positive 24 weeks after α-interferon therapy, which was associated with mutations of nt1896, nt1814, nt1762 and nt1764. In the patients, that HBV DNA levels decreased or were undetectable, but rebounded later after antiviral therapy by lamivudine was associated with mutations of aa528 and(or) aa552(i.e.YMDD mutation), which resulted in lamivudine-resistance. YMDD mutation was prone to occur 52 weeks after lamivudine therapy in some chronic hepatitis B patients (26.4%). Nt1896 mutation was common in most chronic hepatitis B patients (68.5%). Chronic severe hepatitis, cirrhosis, and primary liver carcinoma were related to the mutations of nt1896, nt1762 and nt1764. CONCLUSIONS:HBV gene mutations could aggravate patient’s condition and affect the efficacy of antiviral therapy. The regular detection of HBV gene mutation is helpful for identification of disease prognosis and adjustment of therapeutic strategy. | Shenzhen Eastlake Hospital, Shenzhen 518020, China (Chen JY) and National Key Laboratory of Virology (Wuhan University) Department of Infectious Diseases, Renmin Hospital, Wuhan University, Wuhan 430060, China(Wang LW, Sun XM and Gong ZJ) | 2005 | Hepatobiliary & Pancreatic Diseases International2005，4，3： | 8 |
| 9 | Progressive transformation of immortalized esophageal epithelial cells显示文摘AIM: To investigate the progressive transformation of immortal cells of human fetal esophageal epithelium induced by human papillomavirus, and to examine biological criteria of sequential passage of cells, including cellular phenotype, proliferative rate, telomerase, chromosome and tumorigenicity.METHODS: The SHEE cell series consisted of immortalized embryonic esophageal epithelium which was in malignant transformation when cultivated over sixty passages without co-carcinogens. Cells of the 10th, 31st, 60th and 85th passages were present in progressive development after being transfected with HPV. Cells were cultivated in a culture flask and 24-hole cultural plates. Progressive changes of morphology, cell growth, contact-inhibition, and anchoragedependent growth characteristics were examined by phase contrast microscopy. The cell proliferation rate was assayed by flow cytometry. The modal number of chromosomes was analyzed. HPV18E6E7 was detected by Western blot methods and activities of telomerase were analyzed by TRAP.Tumorigenicity of cells was detected with soft agar plates cultivated and with tumor formation in SCID mice.RESULTS: In morphological examination the 10th passage cells were in good differentiation, the 60th and 85th passages cells were in relatively poor differentiation, and the 31st passage cells had two distinct differentiations. The characteristics of the 85th and 60th passage cells were weakened at contact-inhibition and anchorage-dependent growth. Karyotypes of four stages of cells belonged to hyperdiploid or hypotriploid, and bimodal distribution of chromosomes appeared in the 31st and 60th passage cells. All of these characteristics combined with a increasing trend. The activities of telomerase were expressed in the latter three passages. Four fourths of SCID mice in the 85th passage cells and one fourth of SCID mice in the 60th passage cells developed tumors, but the cells in the 10th and 31st passage displayed no tumor formation.CONCLUSION: In continual cultivation of fetal esophageal epithelial cells with transduction of HPV18E6E7, cells from the 10th to the 85th passage were changed gradually from preimmortal, immortal, precancerous to malignantly transformed stages. All of these changes were in a dynamic progressive process. The establishment of a continuous line of esophageal epithelium may provide a in vitro model of carcinogenesis induced by HPV. | Zhong-Ying Shen Li-Yan Xu Min-Hua Chen Jian Shen WeiJia Cai,Department of Tumor Pathology Medical College of Shantou University,Shantou 515031,Guangdong Province,China Yi Zeng,Institute of Virology,Chinese Academy of Preventive Medicine.Beijing 100052,China | 2002 | World Journal of Gastroenterology2002，8，6： | 8 |
| 10 | Genomic research for important pathogenic bacteria in China显示文摘Rapid accumulation of bacterial genomic data offered an unprecedented opportunity to understand bacterial biology from a holistic view of point.We can thus closely look at the way in which a pathogen is evolved,and these data has been applied to molecular epidemiology and microbial forensics,and screening of novel diagnostic,vaccine and drug targets.The newly developed high-throughput low-cost sequencing technologies,such as 454,Solexa and SOLiD,will promote the acquisition and application of genomic data in new research areas that we dared not imagine previously,such as the metagenomics of human gastric-intestinal tract,for better and comprehensive understanding of human health and disease. | YANG RuiFu1,GUO XiaoKui2,YANG Jian3,JIANG YongQiang1,PANG Bo4,CHEN Chen5,YAO YuFeng2,QIN JinHong2 & LI QingTian2 1 Laboratory of Analytical Microbiology,State Key Laboratory of Pathogen and Biosecurity,Beijing Institute of Microbiology and Epidemiology,Beijing 100071,China 2 Department of Medical Microbiology and Parasitology,Institutes of Medical Sciences,Shanghai Jiao Tong University School of Medicine,Shanghai 200025,China 3 State Key Laboratory for Molecular Virology and Genetic engineering,Institute of Pathogen Biology,Chinese Academy of Medical Sciences,Beijing 100176,China 4 State Key Laboratory for Infectious Disease Prevention and Control,Institute for Communicable Disease Control and Prevention,Chinese Center for Disease Control and Prevention,Beijing 102206,China 5 Beijing Genomics Institute at Shenzhen,Shenzhen 518083,China | 2009 | Science China(Life Sciences)2009，52，1： | 8 |
| 11 | High-yield expression of recombinant SARS coronavirus nudeocapsid protein in methylotrophic yeast Pichia pastoris显示文摘AIM: Nucleocapsid (N) protein plays an important role in reproduction and pathological reaction of severe acute respiratory syndrome (SARS) coronavirus (SCoV), the antigenicity of the protein is better than spike (S) protein.This study was to find a highly specific and antigenic recombinant SCoV nucleocapsid (rSCoVN) protein, and to provide a basis for further researches on early diagnosis of SARS.METHODS: Full length cDNA of SCoV nucleocapsid (SCoVN) protein was amplified through polymerase chain reaction (PCR) and cloned into yeast expression vector pPIC3.5K to construct plasmid of pPIC3.5K-SCoVN. The plasmid was linearized and then transformed into Pichia pastoris (P.pastoris) GS115 (His^+ Mut^+) by electroporation. His^+Mut^+ recombinant strains were identified by PCR and cultivated on MM/MD plates. The influence of different factors on biomass and rSCoVN protein production during induction phase, such as various induction media, dissolved oxygen (DO) and different final concentrations of methanol, was subsequently studied. The expression level and activation were detected by SDS-PAGE and Western-blot respectively.RESULTS: All of the recombinants were His^+Mut^+ after transformation of P.pastoris with linearized plasmids. The BMMY medium was optimal for recombinant ScoVN (rSCoVN) protein expression and growth of the recombinant strains.The final optimal concentration of methanol was 20 ml_/L,the DO had a significant effect on rSCoVN protein expression and growth of recombinant strains. The rSCoVN protein expressed in recombinant strains was about 8% of the total cell protein, 520 mg/L of rSCoVN protein was achieved,and a maximum cell A at 600 nm of 62 was achieved in shake flask culture. The rSCoVN protein had a high specificity against mouse-anti-SARS-CoVN-mAb and SARS positive sera, but had no cross-reaction with normal human serum.The biological activity of rSCoVN expressed in P.pastoris was about 4-fold higher than that expressed in Ecoliwhen the same rSCoVN protein quantity was used.CONCLUSION: Active recombinant severe acute respiratory syndrome (SARS) coronavirus nucleocapsid (rSCoVN) protein can be successfully expressed in recombinant methylotrophic yeast P.pastoris GSl15. The rSCoVN protein has a high specificity against SARS-CoVN-mAb and SARS positive sera, but has no cross-reaction with normal human serum.This provides a basis for further researches on the early diagnosis of SARS and the mechanism of SCoV. | Ru-Shi Liu Kun-Yu Yang Jian Lin Yi-Wei Lin Zhi-Hong Zhang Jun Zhang Ning-Shao Xia The Key Laboratory for Cell Biology and Tumor Cell Engineering of the Ministry of Education The Research Center for Medical Molecular Virology of Fujian Province,Xiamen University,Xiamen 361005,Fujian Province,China | 2004 | World Journal of Gastroenterology2004，10，24： | 8 |
| 12 | Engineering infectious foot-and-mouth disease virus in vivo from a full-length genomic cDNA clone of the A/AKT/58 strain显示文摘Two full-length genomic cDNA clones, pTA/FMDV and pCA/FMDV, were constructed that contained three point-mutants [A174G and A308G (not present in pTA/FMDV); T1029G] in the genome compared with the wild type A/AKT/58 strain of foot-and-mouth disease virus. These two viruses were rescued by co-transfection of pCA/FMDV with pCT7RNAP, which can express T7 RNA polymerase in BHK-21 cell-lines, or by transfection of the in vitro transcribed RNA. Their biological properties were analyzed for their antigenicity, virulence in suckling-mice (LD50) and growth kinetics in BHK-21 cells. The in vivo rescued viruses showed high pathogenicity for 3-day-old unweaned mice (LD50=10?7.5). However, the in vitro transcribed RNA derived from pTA/FMDV had lower pathogenicity for suckling-mice (LD50=10?6), and the in vivo transcribed RNA recovered from pCA/FMDV co-transfected with pCT7RNAP showed no significant differences from the wild type virus. These data showed that recovery of the infectious foot-and-mouth disease virus directly from the use of in vivo techniques was better than from in vitro methods. Furthermore, the reverse genetic procedure technique was simplified to a faster one-step procedure based on co-transfection with pCT7RNAP. These results suggest that in vivo RNA tran- scripts may be more valuable for engineering recombinant foot-and-mouth disease virus than in vitro RNA transcripts, and may contribute to further understanding of the biological properties, such as replication, maturation and quasispecies, of the foot-and-mouth disease virus. | BAI XingWen1, LI PingHua1, CAO YiMei1, LI Dong1, LU ZengJun1, GUO JianHong1, SUN DeHui1, ZHENG HaiXue2, SUN Pu1, LIU XiangTao1, LUO JianXun1 & LIU ZaiXin1 1 Key Laboratory of Animal Virology of Ministry of Agriculture, National Foot-and-Mouth Disease Reference Laboratory of China, State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute of Chinese Academy of Agricultural Sciences, Lanzhou 730046, China 2 Veterinary Research Institute, Guangdong Agricultural Academy of Sciences, Guangzhou 510640, China | 2009 | Science China(Life Sciences)2009，52，2： | 6 |
| 13 | Structural and functional analysis of denitrification genes in Pseudomonas stutzeri A1501显示文摘Four gene clusters associated with denitrification were identified in the genome of A1501 strain, nar, nir, nor and nos, including 40 genes totally, which encode proteins for sub-stance transportation, gene regulation and reductases. The three gene clusters, nir, nor and nos are adjacent on chromosome and are far from nar gene cluster. Compared with other denitrifying bacteria, the 40 denitrification genes in A1501 strain compose a complete denitrification catalysis system. In A1501 strain, this system has the following characteristics: (i) only one copy of narK gene is found in nar gene cluster; (ii) a narM gene is present between narK and narG; (iii) two genes, dnarE and orfl are identified at downstream of narX and narL genes, of which dnrE per-haps is a transcriptional factor belonging to FNR family; (iv) there are 16 nir genes in A1501, the most in the known denitrifying bacteria; (v) it is for the first time that norR gene has been found in A1501 and also in Pseudomonas; (vi) nos gene cluster is relatively conservative, with a com-pletely identical composition and arrangement of genome to the reference bacteria strain. | YAN Yongliang1,2, YANG Jian2, CHEN Lihong2, YANG Fan2, DONG Jie2, XUE Ying2, XU Xingye2, ZHU Yafang2, YAO Zhijian3, LIN Min4, WANG Yiping5 & JIN Qi1,2 1. College of Biological Sciences, China Agricultural University, Beijing 100094, China 2. State Key Laboratory for Moleclular Virology and Genetic Engineering, Beijing 100176, China 3. National Center for Human Genome Research, Beijing 100176, China 4. Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing 100081, China 5. College of Life Sciences, Peking University, Beijing 100871, China | 2005 | Science China(Life Sciences)2005，48，6： | 6 |
| 14 | Effects of quorum sensing autoinducer degradation gene on virulence and biofilm formation of Pseudomonas aeruginosa显示文摘The aiiA gene from Bacillus thuringiensis was cloned into the Pseudomonas/E. coli shuttle vector and transformed into Pseudomonas aeruginosa strain PAO1. Western blotting showed that the AiiA protein was expressed in PAO1. After induction by IPTG for 6 h and 18 h, expression of the aiiA gene in PAO1 completely degraded the quorum sensing autoinducers N-acylhomoserine lactones (AHLs): N-oxododecanoyl-L-homoserine lactone (OdDHL) and N-butyryl-L-homoserine lactone (BHL). The re- duced amount of AHLs in PAO1 was also correlated with decreased expression and production of several virulence factors such as elastase and pyocyanin. AiiA expression also influenced bacterial swarming motility. Most importantly, our studies indicated that aiiA played significant roles in P. aeruginosa biofilm formation and dispersion, as observed by the differences of the biofilm formation on liquid and solid surfaces, and biofilm structures under a scanning electron microscope. | WANG Yao1, DAI Yue1,2, ZHANG Yong1,2, HU YangBo1,2, YANG BaoYu1 & CHEN ShiYun1 1 Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China | 2007 | Science China(Life Sciences)2007，50，3： | 6 |
| 15 | Recent advances in molecular diagnostics of hepatitis Bvirus显示文摘Hepatitis B virus(HBV)is one of the important global health problems today.Infection with HBV can lead to a variety of clinical manifestations including severe hepatic complications like liver cirrhosis and hepatocellular carcinoma.Presently,routine HBV screening and diagnosis is primarily based on the immuno-detection of HBV surface antigen(HBsAg).However,identification of HBV DNA positive cases,who do not have detectable HBsAg has greatly encouraged the use of nucleic acid amplification based assays,that are highly sensitive,specific and are to some extent tolerant to sequence variation.In the last few years,the field of HBV molecular diagnostics has evolved rapidly with advancements in the molecular biology tools,such as polymerase chain reaction(PCR)and real-time PCR.Recently,apart of PCR based amplification methods,a number of isothermal amplification assays,such as loop mediated isothermal amplification,transcription mediated amplification,ligase chain reaction,and rolling circle amplification have been utilized for HBV diag-nosis.These assays also offer options for real time detection and integration into biosensing devices.In this manuscript,we review the molecular technologies that are presently available for HBV diagnostics,with special emphasis on isothermal amplification based technologies.We have also included the recent trends in the development of biosensors and use of next generation sequencing technologies for HBV. | Sibnarayan Datta Soumya Chatterjee Vijay Veer Molecular Virology Laboratory | 2014 | World Journal of Gastroenterology2014，20，40： | 6 |
| 16 | Complex positive selection pressures drive the evolution of HIV-1 with different co-receptor tropisms显示文摘HIV-1 co-receptor tropism is central for understanding the transmission and pathogenesis of HIV-1 infection. We performed a genome-wide comparison between the adaptive evolution of R5 and X4 variants from HIV-1 subtypes B and C. The results showed that R5 and X4 variants experienced differential evolutionary patterns and different HIV-1 genes encountered various positive selection pressures, suggesting that complex selection pressures are driving HIV-1 evolution. Compared with other hypervariable regions of Gp120, significantly more positively selected sites were detected in the V3 region of subtype B X4 variants, V2 region of subtype B R5 variants, and V1 and V4 regions of subtype C X4 variants, indicating an association of positive selection with co-receptor recognition/binding. Intriguingly, a significantly higher proportion (33.3% and 55.6%, P<0.05) of positively selected sites were identified in the C3 region than other conserved regions of Gp120 in all the analyzed HIV-1 variants, indicating that the C3 region might be more important to HIV-1 adaptation than previously thought. Approximately half of the positively selected sites identified in the env gene were identical between R5 and X4 variants. There were three common positively selected sites (96, 113 and 281) identified in Gp41 of all X4 and R5 variants from subtypes B and C. These sites might not only suggest a functional importance in viral survival and adaptation, but also imply a potential cross-immunogenicity between HIV-1 R5 and X4 variants, which has important implications for AIDS vaccine development. | ZHANG ChiYu1*, DING Na1, CHEN KePing1 & YANG RongGe2* 1Institute of Life Sciences, Jiangsu University, Zhenjiang 212013, China 2HIV Molecular Epidemiology and Virology Research Group, State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China | 2010 | Science China(Life Sciences)2010，53，10： | 5 |
| 17 | Prokaryotical expression of structural and non-structural proteins of hepatitis G virus显示文摘AIM To study the epitope distribution of hepatitis G virus (HGV) and to seek for the potential recombinant antigens for the development of HGV diagnositic reagents.METHODS Fourteen clones encompassing HGV gene fragments from core to NS3 and NS5 were constructed using prokaryotic expression vector pRSET and (or)pGEX. and expressed in E. coli. Western blotting and ELISA were used to detect the immunoreactivity of these recombinant proteins.``RESULTS One clone with HGV fragment from core to El(Gl). one from E2 (G31), three from NS3 (G6, G61, G7),one from NS5B (G821) and one chimeric fragment from NS3and NS5B (G61 821) could be expressed well and showed obvious immunoreactivity by Western blotting.One clone with I-KGV framment from NS5B (G82) was also well expressed, but could not show immunoreactivity by Western blotting. No obvious expression was found in the other six clones. All the expressed recombinant proteins were in inclusion body form, except the protein G61 which could be expressed in soluble form. Further purified recombinant proteins Gl, G,31, G61, G821 and G61 821were detected in indirected ELISA as coating antigen respectively. Only recombinant Gl could still show immunoreactivity, and the other four recombinant proteins failed to react to the HGV antibody positive sera.Western blotting results indicated that the immunoactivity of these four recombinant proteins were lost during purification.``CONCLUSION Core to El, E2. NS3 and NS5 fragment of HGV contain antigenic epitopes, which could be produced in prokaryotically expressed recombinant proteins. A high. yield recombinant protein (Gl) located in HGV core to E1 could remain its epitope after purification, which showed the potential that G1 could be used as a coating antigen to develop an ELISA kit for HGV specific antibody diagnosis. | Ning-Shao Xia~1 Hai-Jie Yang~1 Jun Zhang~1 Chang-Qing Lin~1 Ying-Bin Wang~1 Juan Wang~1 Mei-Yun Zhan~2 MH Ng~3 1 Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering,Xiamen University,Xiamen 361005,Fujian Province,China2 Institute of Virology,Chinese Academy of Preventive Medicine Beijing 100052,China3 Department of Microbiology,Hoog Kong University,Hongkong,China | 2001 | World Journal of Gastroenterology2001，7，5： | 4 |
| 18 | Comparative analysis of whole genome structure of Streptococcus suis using whole genome PCR scanning显示文摘An outbreak associated with Streptococcus suis infection in humans emerged in Sichuan province, China in 2005. The outbreak is atypical for the apparent large number of human cases, high fatality rate and geographical spread. To determine whether the bacterium has changed, we compared both human and animal isolates from the Sichuan outbreak with those collected previously within China and in other countries using whole genome PCR scanning (WGPScaning) comparative sequencing of several known virulence factor genes and multilocus sequence typing (MLST) analysis. WGPScanning analysis showed that all primer pairs yielded PCR products of the expected sizes in all four strains tested. The nucleotide sequences of all the detected virulence factor genes are identical in the four strains and MLST results showed that the four isolates studied and reference strain all belonged to the ST1 com-plex. No new genetic changes were found in the genome structure of the isolates from this Sichuan outbreak. | XIONG ZhaoHui1*, WEI CanDong1*, YANG Jian1, PENG JunPing1, XU XingYe1, WANG Yu2 & JIN Qi1,3 1 State Key Lab for Molecular Virology and Genetic Engineering, Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 100176, China 2 Chinese Center for Disease Control and Prevention, Beijing 100050, China 3 Institute of Pathogen Biology, Chinese Academy of Medical Sciences, Beijing 100730, China | 2008 | Science China(Life Sciences)2008，51，1： | 4 |
| 19 | The flhDC gene affects motility and biofilm formation in Yersinia pseudotuberculosis显示文摘The flagella master regulatory gene flhDC of Yersinia pseudotuberculosis serotype III (YPIII) was mu- tated by deleting the middle region and replaced by a tetracycline resistant gene, and the subsequent mutant strain named YPIII?flhDC was obtained. Swimming assay showed that the swimming motility of the mutant strain was completely abolished. The promoter region of the flagella second-class regula- tory gene fliA was fused with the lux box, and was conjugated with the mutant and the parent strains respectively for the first cross. LUCY assay result demonstrated that flhDC regulated the expression of fliA in YPIII as reported in E. coli. Biofilm formation of the mutant strain on abiotic and biotic surfaces was observed and quantified. The results showed that mutation of flhDC decreased biofilm formation on both abiotic and biotic surfaces, and abated the infection on Caenorhabdtis elegans. Our results suggest that mutation of the flagella master regulatory gene flhDC not only abolished the swimming motility, but also affected biofilm formation of YPIII on different surfaces. The new function of flhDC identified in this study provides a novel viewpoint for the control of bacterial biofilm formation. | WANG Yao1, DING LiSha1,2, HU YangBo1,2, ZHANG Yong1,2, YANG BaoYu1 & CHEN ShiYun1 1 Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China | 2007 | Science China(Life Sciences)2007，50，6： | 4 |
| 20 | The developmental fate of green fluorescent mouse embryonic germ cells in chimeric embryos显示文摘Primordial germ cells (PGCs), as precursors of mam-malian germ lineage, have been gaining more attention as anew resource of pluripotent stem cells, which bring a greatpossibility to study developmental events of germ cell invitro and at animal level. EG4 cells derived from 10.5 dayspost coitum (dpc) PGCs of l29/svJ strain mouse wereestablished and maintained in an undifferentiated state.With an attempt to study the differentiation capability ofEG4 cells with a reporter protein: green fluorescence pro-tein, and the possible application of EG4 cells in the re-search of germ cell development, we have generated severalEG4-GFP cell lines expressing enhanced green fluorescenceprotein (EGFP) and still maintaining typicaI characteris-tics of pluripotent stem cells. Then, the differentiation ofEG4-GFP cells in vitro as well as their developmental fatein chimeric embryos which were produced by aggregatingEG4-GFP cells to 8-cell stage embryos were studied. Theresults showed that EG4 cells carrying green fluorescencehave a potential use in the research of germ cell develop-ment and other related studies. | XU XIN YONG SHEN YU HSIAO CHlEN TSUNGSUMIO SUGANO YUAN CHANG YAN(Shanghai Institute of Cell BiolOgy, Chinese Academy ofScience, Shanghai 200031, China)(Department of Virology, The Institute oj Medical Sci-ence) The University of Tokyo, Tokyo, Japan) | 1999 | Cell Research1999，9，3： | 3 |
您所在的机构暂未开通此部分的功能，请联系管理员