2003 Vol.18(6)

Research Article

Targeting the 5 untranslated Region ofHepatitis C virus by Intracellularly Expressed Small Interfering RNA

WU Shu.wen, FANG Cong, PAN Ji-an, TIAN Bo, GUO Deyin

2003, 18(6): 518

Abstract:In this study,we inserted the 5 untranslated region(UTR)of Hepatitis C virus(HCV) genome into the upstream of the reporter genes of enhanced green fluorescent protein (eGFP)and luciferase.an d we also constructed the expression vector that Can express the short interfering RNAs (siRNA) against the HCV 5 .UTR.The 5 .UTR.eGFP/luciferase an d the siRNA-prod ucing plasmid were cotran sfected into Hela cells,an d the inhibition efect was detected by the intensity of the fluorescence an d luminescence.Th e vesults showed that the light from the cotransfected cells was obviously weaker than the negative control both in quality an d in quan tities,while density of the cotran sfected cells had no diference with the control plasmid as detected by nucleus staining.TlliS work demonstratedthat certain siRNA Can targetthe 5 UTR ofHCV whilenotoxic efecthadbeenobserved in the cells.TlliS work is the basis for future research in which RNAi activity is supposed to be utilized in the gene therapy with the the HCV infection.The siRNA is expressed intracellularly by vectors instead of chemical synthesis,an d a new method Can be used as a model to quickly an d safely screen effcctive siI AstargetingHCV

Efect of Human Cytomegalovirus on Proliferation of M ulfipotential Hematopoietic Progenitors in vitro

LIU Bin, LIU Wen-jun, HU Xiao, GUt Qu, DEN Zheng, LIN Jiang, ZHAN Pin

2003, 18(6): 519

Abstract:To investigate the suppression effect of Human cytomegalovirus(HCMV)on multipotential hematopoietic progenitors(CFU—Mix)in vitro,colony forming unit—assay was applied to observe the effect of HCM V—AD169 strain on CFU—M ix of cord blood.1[11e technique of PCR Was used to demonstrate the existence of HCM V-DNA in the colony cells of cultured CFU-M ix.The numbers of CFU—M ix colonies in the groups infected with HCM V were significan tly less than that in control group, an d it showed an increase tendency with the decrease of HCMV concentration.1[11e suppression efect showed a dose—dependent fashion:the higher the HCM V.At)169 conce ntration.the more the CFU—Mix colonies decreased .111e pcak of CFU—M ix colonies in control groups an d groups infected with HCM V appeared on the same time(10~12th day),the lasting time of the CFU—Mix colonies in groups infected with HCM V Was significan tly shorter than that in control groups.HCNⅣ 一DNA Was positively detected in the colony cells of viral infected groups by PCR.while negative in the control groups.HC Ⅳ 一AD169 strain inhibited the diferentiation and proliferation of CFU—Mix by infec ting the hematopo ietic progenitors.HCMV may cause the suppression of hematopoiesis by direct infection,which may be the main reason of HCMV infection associated with anemia,neutropenia an d thrombocytope nia.

DNA M icroarray for M onitoring Genetic Variability ofHepatitis B virus during Lamivudine Therapy

GAO Ying, CHEN Rui, SONG Wen, CHEN Cheng-bin, QI Zhi-, JING Li, SUN Jin-ying, QIAN Shao

2003, 18(6): 523

Abstract:The Hepatitis B virus(HBV)oligochip was made according to the sequence of HBV polymerase gene.7 genotypes and 4 sero—subtypes of HBV,as well as position rtV173,~.L180,rtlVl21M, rtV207 in the reverse transcriptase(rt)domain of HBV polymerase,were detected with the chip.45 patients were divided into A an d B groups according to their ALT levels.Serum samples for chip analysis were obtained at 0,3,6,9,12 months of treatment.Among 45 patients,39 were genotype C and subtype adr,6 were genotype B an d subtype adw.Among 38 patients whom were treated continuously for 12 months,1 lamivudine resistant mutan t was discovered in 17 of A group with high ATL level,4 varian ts were momtored in 21 of B group with normal ALT leve1.All varian ts were rtM 204V an d rtL180M ,2 of them were mixed with HBV wild type .Th e rtM 204V mutan t was found at 6 months of thempy,the~L180M mutant was detected afterward.Th e results obtained by sequencing ofthe 10 PCR products an d chip arraying were almost the same,the only diferent was that 1 varian t at position rtV173 Was not detected by the gene chip.Further an alysing HBV DNA values,ALT levels an d HBeAg seroconversion in relation to HBV mutants,the results showed that a more rapid occurrence of varian t Was assoc iated with HBV DNA re—elevation.whereas not associated with HBV DNA values an d ALT levels of pretreatm ent.Th e HBV gene chip could monitor genetic variability of HBV,it is a promi sing method forevaluating effects oflamivudine therapy.

Cloning,Expression and Analysis of HCV Ns5b Polymerase gene from Chinese serum

YANG Zhen, JIANG Jiang—dong, QI Zi—bai, CHEN Hong—shan, Zhang Hua—yuan, LI He—ming

2003, 18(6): 530

Abstract:To ampUfy Hepatitis C virus(HCV)polymerase sequence and express HCV NS5b protein in order to,in the next,establish a molecular model of HCV replication.RT—PCR method was used to amplify HCV NS5b polymerase gene from a Chinese HCV(+1 patient’S serum. e polymerase fragment Was constructed in the plasmid pET一30a an d expressed in E coli.HCV NS5b protein Was identified by W lestern blot with a monoclonal an tibody against HCV NS5b.Sequence analysis showed tllat the isolate had 69% 一95% an d 89%一97% homologies to the reported HCV sequences in respect to nucleotide an d amino acid respectively.HCV NS5b gene was expressed at a high level an d the molecular weight ofthe expressed prod uct was 65kDa.which was within the ran ge of expectation.This protein Was confirmed to be HCV NS5b by Western blot.HCV NS5b from a Chinese patient Can be Success—fully cloned an d expressed with pET一30a plasmid an d E coli. is protein could be used to establish a molecular mod el of HCV replication.

Antiviral Activity of Algefacient and Anti-inflammatory Against Influenza Virus in vitro and in vivo

LIU Zhao, YANG Zhan, XIAO Hong, WEN Lil, WANG Zhen

2003, 18(6): 534

Abstract:To observe the antiviral activity of Algefacient and anti-inflammatory(AI)against influenza virus,cell culture technique was used in M DCK cells to get virus inhibitory rate an d virus tiler by MTT assay an d hemagglitination test.Influenza virus infection model was established in mice,to observe the protection efect to mi ce death ,the inhibitory efect to pulmonary index and pulmonary virus titer.The results showed that 160ug/mL Algefacient an d anti-inflammatory Can completely inhibit the proliferation of influenza virus in MDCK cel1.0.1 gg, 0.5g/kg.1.2g,/kg dosage med cme orally given for 5 days could significan tly decrease the mortality rate,prolong the living time of infec ted mi ce, decrease the pulmonary index and pulmonary virus hemagglitination titer(PO.oi).This efect is similar to that of virazole at the same dosage leve1.W e conclude that AI is an efective anti-influenz a virus.compound/n vitro and in vivo.

Construction of an Eukaryotic Vector Containing the Full-length HCV cDNA and Its Expression in M ammalian Cell

JIAO Cheng.Song, WANG Sheng.Qi, ZHANG He.Qiu, LING Shi.Gan

2003, 18(6): 538

An eukaryotic vector containing the full—length Hepatitis C virus(HCV)gene,pCi—HCV,was successfully constructed in this study.After~ansfected into HepG2 cells.it Was revealed to expleSS HCV C and NS3 proteins in the cloned cells by immunofluorescence and immunohistochemistry as Say respectively.It could be used for the experiments of the construction of HCV transgenic cellular model and the further study on the replication of HCV through cDNA.

SARS-CoV Infection Induces Apoptosis of Vero E6

YAN Ran, SHEN Chao, LEI Lei, ZHENG Cong—yi, XIAO Geng—fu, GUO De—yin, ZHU Ymg, YAN Hui一min

2003, 18(6): 541

Abstract:To determine if SARS—associated coronavirus(SARS—CoV)induces apoptosis.we studied the SARS—CoV infected Vero E6 cells by agarose gel electrophoresis.indirect fluorescent staining for infection an d Hoechst 33528 staining for nuclei,as well as by flow cytometry.It was found that SARS—C0V infected Vero E6 cells showed typical apoptosis characteristics.Au the typical apoptotic ceHs were in late—infection period.Most of the cells with cytopathic effect(CPE)showed nuclei witll condensed chromatin or fragmented into apoptotic bodies.It was suggested that SARS—CoV infection induces apoptosis of Vero E6.

Isolation and Identification of SARS.CoronaviFUS

JIANG Li—fang, ZHAO Wei, YAN Hui-jun, FANG Dan.yun, ZHOU Jing-jiao, LONG bei-guo, WU yi.fang, ZHOU Jun.mei, LIANG Yu, ZHANG Wen.bing, WU Qiang, GUO Hui—yu

2003, 18(6): 544

Abstract:To isolate and identify the etiologic agent of severe acute respiratory syndrome(SARS), the throat swabs an d gargle of patients with SARS were collected.We inoculated the specimens onto a number of cell lines including Vero,Vero E6,M DCK,Hela,Hep一2,HP an d HEL cells.The isolates were identified by thin—section electron.microscopy,indirect.immunofluorescence,neutralization test, RT—PCR an d nucleotide sequence an alysis.Using cell culture techniques.a coronavirus was isolated from patient with SARS.Four celllines,Vero,Vero E6,HP an d MDCK cells,showed cytopathic efec t. 1]he infected cells showed strong cytoplasmi c an d membran ous staining with a convalescent—phase seruln from the patients with SARS in an indirect—immunofluorescence staining.The cytopathic efect of the viruses clould been neutralized by convalescent serum.Under elec tron—microscopy,a large num be r of coronavirus—like particles were obsewed in the infected cells.W ith specific primers.the specific cDNA fragments were amplified by reverse transcription—polymerase chain reaction(RT—PCR1 from infected cels an d the nucleotide sequence analysis showed that homology of the amplified fragm ents to the SARS—coronavirus(SARS·CoV)previously reported was 100%.A SARS—CoV Was isolated from patients with SARS.T}liS virus was closely associated with SARS.

Coexpression and Application ofN Gene ofPorcine reproductive and respiratory syndrome virus and HA gene ofInfluenza Virus

XU Li, SU Xiao, WANG Ling, SU Xin, REN Xue, SU Chun, CHEN Pu

2003, 18(6): 548

Abstract:From to the nucleotide sequences of haemoagglutinin gene of Influenza virus and Porcine R rD c and Respiratory Syndrome Virus(PRRSV)VR2332 in GenBank,a pair of primers which includes the main sequences of haemoagglutinin(HA)gene(33bp)was designed to amplify N gene (ORF7)of PRRSV by RT—PCR.The amplified fragment and pET一32a plasmid were digested by BamHI and XhoI.A recombinant plasmid nam ed pETHN was constructed and transformed into BL21(DE3). Consequently,the target protein was expressed by IPTG induction,and the purified fusion protein was obtained by His—binding purification kit.As a result latex—agglutination test Was set up an d plenty of serum sam ples were tested by the method.Th e results showed the method had same sensitivity and specificity and had 93.8% accord rate compared with ELISA(IDEXX)diagnosis kit.

Isolation and Identification of Swine hlfIuenza Virus

WU Rui, JIN Mei—fin, CHEN Huan-chuen, WANG Guei-hua, JIANG Zeng-hai

2003, 18(6): 553

Abstract:Three H3 subtype strains of Swine influenza virus(SlV),which were named SSH1,SFJ1 and SHB1,were isolated from Shanghai,Fujian and Hubei.These isolates could grow and replicate in chicken emb~o,and the hemagglutinin(HA)values were 1:2 ,1:2 and 1:2 ,respectively.The hemagglutinin inhibitor(HI)titers of H subtype antiserum were 1:2 ,1:2 and 1:2。,respectively, whereas they were negative in HI assays with Newcastle disease an tiserum.Under electron micrograph, the virions showed various shapes.The mice infected witl1 allantoic fluid could arise syndromes an d pathology;SIV could be isolated again and amplified by RT-PCR from the lung.RNA Was extracted from SIV which Was purified from infected allantoic fluid,an d expected ban d Was observed via RT—PCR.

Variant Analysis and Three-Dimensional Structure Prediction of the Capsid Protein ofthe Chinese Early Isolate NJ85 ofRabbithemorrhagic disease virus

WANG Yong—shan 一, LU Cheng—ping, ZHOU Zong—an

2003, 18(6): 557

Abstract:The capsid protein gene(vp60)of Rabbit hemorrhagic disease virus(RHDV)isolate NJ85 was amplified and sequenced.vp60 gene of NJ85 was in size of 1 740nt an d encoding 579aa. Comparison with other Chinese field isolates W X84 an d TP showed that the homology were 92.7% an d 97.2% for nucleofide sequence;96.1% an d 98.6% for amino acid sequence respectively.Alignment with other 16 sequences of RHDV isolated from other countries registe in GenBank showed that the homology was 83.7% ~ 97.0% for nucleotide and 90.5%~ 99.0% for amino acid sequence.The results indicated that the sequence of vp60 in diferent RHDV isolates was highly homologous.In the all six regions ofvp60 gene,low degree ofvariation ofvp60 was found in the regions A,B,D,F and relative high degree of variation in the regions C and E.Based on vp60 sequence,phylogenetic an alysis showed that the historic RHDV isolates were divided into 3 branches of the lineage of RHDV according to the am ino acid sequences and 4 branches according to the nucleotide sequences.Th ere was no obvious correlation between geographical region,historic period and homological degree.Three Chinese field isolates lay in 2 diferent branches of the RHDV lineage,while EBHSV formed an other fineage.Th e molecular weight,isoelectric point,hydrophobicity,2-dimensional an d 3-dimensional structure of NJ85 vp60 were de~rmined and predicted on the theory of bioinformatics.The major secondary structure,13 一sheet,contributed to the stability of vp60.Based on the structural model,the architecture of NJ85 capsid was 32 cup—shaped depressions.Th e capsid was composed of 90 A/B5 an d C/C2 dimers formed by the single unit of vp60.Th e conformation of the single unit in dimer existed in thre forms of A,B and C.Th e single unit of Vp60 had a protruding(P)domain connected by a flexible hinge to a shell(S) domain.P domain was subdivided into two subdomains,P1 an d P2.P2 subdomain that located at the surface of the capsid contained the determinants of strain specificity an d erythrocyte binding site.

Isolation and Identification of a M ouse Poxvirus an d Its Infectivit

AN Xue-fang, LIU Feng-song, FANG Ming-gang, ZHU You-, WANG Han-zhong

2003, 18(6): 563

Mousepoxvirus has been isolated from diferent pathological tissues in deed mouse that natively infected by virus.In negative stained preparations.the size of the virus particles Was l60~ 19Ohm X250~ 300nm and the virus the particle revealed ovoid·shape.Tl1e healthy Blab/C mouse were infected by injection with purified virus particles,resulting in the death of mouse and producing the same virus particles as inoculated virus.Ttle electron microscopy of an ultrathin section confirmed that viral replication an d assembly of virions occurred in the cytoplasm of diferent pathological tissues infec ted by viruses such as liver,lung.kidney,intestine an d pan creas.These results demonstratedⅡlat the virus should been classified into Poxviridae.

The Study on the Infection of Rabbits with Bovine Foamy Virus 3026’

YU Hong, KONG Xiaohong, XUAN Chenghao, WANG Jinzhong, CHEN Qi—rain, GENG Yun-qi

2003, 18(6): 566

Abstract:Rabbits were injected with a single intravenation of Bovine foamy virus 3026(BFV3026)· infected cells in the ear and monitored for sera-conversion serologically up t0 l year.Results of the serological an d virus-rescue assays indicated that all animals were persistently infected with BFV3026 an d showed sustained BFV3O26.spec ific humoral immune response.BFv3026 Was rescued by co-cultivation with fetal bovine lung(FBL)cells from the spleen,kidney,lung,liver and peripheral blood leukocytes of the infected an imals.Virus sequence in poZ was、recovered an d amplified from the tissues where the virus Was rescued from,such as from the heart,brain,bone marrow,mesentery an d the pan creas.In addition.BFv transcripts could be detected in PBL by RT.PCR. S animal model might be usefulfor studyingtheinteractionbe tweenBFv an dBIV

Cloning and Expression of Superoxide Dismutase Gene Encoded by Spotoptera exigua Multi Nucleopolyhedrovirus

ZHANG Hai—yuan, NIU Guo—dong, HONG Jing-jun, ZHANG Zhong—xin

2003, 18(6): 576

Abstract:Superoxide dismutases scavenge superoxide radicals and protect cells from oxidative stress sod gene of Spotoptera exigua Multi Nucleopoleohedrovirus(SeMNPV)from China has been cloned an d expressed in E.coli with the activity of SOD being 29 1.1 9U,mL.DNA sequence an alysis showed mat sod gene of SeMNPv encoded 1 5 1 amino acids.The sequences homology between SeMNPv sod gene an d human sodl gene was 50% ,an d 64% between SeM NPV an d LdNPV,63% be tw e n SeM an d HaSNPV,HcNPV,BmNPV,65% between SeMNPv and AcNPV

Nucleotide Sequence Analysis and Prokaryotic Expression of S7 cDNA from Dendrolimus punctatus CPV Hunan Strain

HONG Jing-jun, ZHANG Hai, ZHAO Shu, DUAN Jia, PENG Hui-yin

2003, 18(6): 581

Abstract:The nucleotide sequence of genome S7 cDNA (AY 1 80908) from Dendrolimus punctatus cypovirus l Hunan strain(DpCPV—HN )was determined.S7 cDNA consists of 1 501 nucleotides and encodes a protein of 448 amino acids with a molecular mass of 49.8 kDa.Th e 5 .an d 3 .terminus conserved sequences are 5 一AGTAA一3 and 5 一GTTAGCC一3 。respectively. en compared wim S7 an d its putative protein of Lyman tria dispar cypovirus l an d Bombyx moil cypovirus 1.97.2% an d 87.0% identities in the nucleotide leve1.and 98.7% an d 92.8% identities in the amino acid level were found。repectively.BLAST search program revealed some similarity between DpCPV·HN P50 an d DnaK·like protein of Mycoplasma hominis.The cDNA fragment encoding DpCPV—HN P50 C259 was also cloned an d inserted into pET.28a expressive vector after being digested with BamH I an d日 d m to construct pET一28a/$7(59 1.1 37 1)recombinant expression vector.Expression of the fusion protein was induced by IPTG in E.col BL21.Th e results indicated that the fusion protein with a molecular mass of 37.3 kDa containing P50C259 was expressed abundan tly,and the fusion protein had an optional level when induced by 1.0mmol/L IPTG over about 2 hours.

Helicoverpa armigera Nucleopolyhedrovirus Triggered Se-UCR Apoptosis is Blocked by Spodoptera exigua Nucleopolyhedrovirus

CHENG Rui, LIANG Chang, NAN Fang, HU Zhi, VLAK M, CHEN Xin-wen

2003, 18(6): 587

Abstract:Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus(HaSNPV)and Spodoptera exigua muUicapsid nucleopolyhedrovirus(SeMNPV)are commercially produced as pesticides.As pe sticides,both viruses have very narrow host range and Can not make cross infection.Trying tO generate a rec ombinant baculovirus with broader host range by CO—infection and co-transfection,we found that HaSNPV could trigger apoptosis of a exigua cell line Se·UCR.which could be blocked by SeM NPV,but apoptosis did not occur in Se一30 1,a cell line also from exigua.W hen infected Se-UCR with 5M OI,theapoptoticbodywasIn’stfound at 12hpi,obvious apoptosis couldbe observedat 24hpi, at the end almost all ceHs were dead at 72 hpi.Those observations were confu-med by genome DNA fragmen-ration analysis.Dot blot an alysis indicated that SeMNPV could also help HaSNPV genome DNA an d then virus repficafion in Se-UCR cells,but not in Se-301.

Cloning and Analysis of Oedaleus asiaticus Entomopoxvirus Spheroidin Gene

ZHAO Chao—yang, W ANG Li-ying, LI Yong-dan, YUN Gui-ling

2003, 18(6): 593

Abstract:TIle coding region of Oedaleus asiaticus EPV spheroidin gene was obtained by PCR.and this fragment Was subsequently cloned,seq uenced an d an alyzed.Tlle data shows OaEPV sph coding re on is 2967bp in size which encodes a ll l l(Da protein.Homology an alysis demonstrated that 0aEPV is closer to Orthoptcran EPVS than Lepidopteran an d Coleopteran EPVS.Phylogenetic tree derived from all known EPVS spheroidin gene indicates that the order of the EPV host is in relationship with the genus of corresponding EPV.which agres wit|l a recent point that “Lepidopteran EPVs an d Orthopteran EPVS should be divided into two distinct genus”.Hydrophobicity plots of these kn own speroidin show that the more distan t relationship of the orders the viruses hOsts be long to.the more diverse of the property of EPV spheroidin to each other.It may be explained as the result of CO.evolutionbe tweentheEPVSan dtheirhos

Prokaryotic Expression of Three bro Genes from Helicoverpa armigera Singlenucleocapsid Nucleopolyhedrovirus and Generation of Antibodies

CHEN M ing—ruing, WU Dong, YUAN Li, CHEN Xin—wen, HU Zhi—hong

2003, 18(6): 597

Abstract:Three baculovirus repeated open reading frame(bro)genes were amplified by PCR from the genome DNA of HaSNPV.The PCR products were cloned into pBluescript KS(+)plasmid.The genes were introd uced into the expression vector pProExHTb.After IFFG induction.the E coli DH5a strain containing each of the recombinant plasmids expressed proteins with molecular weights of 32 kDa、64 kDa an d 58 kDa,respectively,which were in agreement with the prospeetation.Th e purified recombinant proteins were used to immune the rabbits separately.Western blot an alysis using the multiclonal an tibodies derived from the rabbits indicated that these an tibodies could react specifically with thetargetproteinsan dwere suitableto beusedforfurtherfunctional an alysisofthebrogenes.

Pathogenic and Immunohistochemical Studies of the HaSNPV Infected Helicoverpa armigera Larvae

OUYANG Zhi-quart, SUN Xiu-lian, DENG Fei, YUAN Li, HU Zhihong

2003, 18(6): 603

Abstract:Here we report the pathogensis process of Helicoverpa armigera larvae infected with Helicoverpa armigera single nucleocapsid nucleopolyhedrovirus(HaSNPV)using H.E staining and immunohistoc hemistry with an tibody against polyhedrin.The fourth instar Helicoverpa armigera larvae were injected with 5×l PFU HaSNPV per larva.H.E staining showed that no apparent pathogensis could be detected in all tissues at 24 hours post infection(hpi).But at 48 hpi,the nucleus ofthe fat body an d trachea epidermis became swollen,an d the shape ofthe cells in these tissues were chan g~ .At 72 h P i,significant hispathogensis were observed in fat body,trachea epidermis an d the epidermis,while no chan ges were found in midgut an d muscles.At 96 hpi,the constitution of the fat body,trachea and epidermis were destroyed.Th e immunohistoc hemistry results indicated the po lyhedrin protein could not be detected at 24 hpi.At 48 hpi,it was found partially expressed in the tissues of fat body,trachea epidermis an d epidermis.From 72 to 96 hpi,the po lyhedrin was found heavily expressed in fat body, trachea epidermis and epidermis.No po lyhedrin was found expressed in midgut untill larvae dead an d themusculewasnotbe infected allthetime.

Harpin Expression and Induction of Bioactivity to Anti-TMV Infection

XU Jin-ping, MENG Xiao-lin, WANG Jian, LU Wei, ZHANG Jun-jie

2003, 18(6): 607

Abstract:Harpin gene A,B,C and D fragments of Erwinia amylovora(Ea)were synthesized.The full length Harpin gene was constructed by ligation,and then cloned into pET-23(+).Th e fusion Harpin protein Was expressed in E.coli BL2 1,purified by His Bind Resin Ni”chromatography and subjected to SDS—PAGE an d Western blot.The Mr of the Harpin was 45 kDa.5pL 301ag/mE Harpin induced hypersensitive response on tobacco or capsicum leaves by using punctures or injection along nervation in laminae respectively.Tobacco an d capsicum were treated with 30pg/mE Harpin protein by spraying over the plant,and then Tobacco mosaic virus(TMV)was inoculated in the plants by mechanical inoc ulation after 5 days.Th e TM V concentration in leaves was determined by ELISA.TM V infection in tobacco an d capsicum treated with Harpin was repressed to a certain extent.

Eficiency and Safety Evaluation of HaNPV Suspension Formulation Containing Chlorfluazuron

ZHANG Zhong—xin, ZHANG Hal—yuan, NIU Guo—dong, YUAN Ke-jing, DUAN Zhi—yong, ZHANG Qiu—hong

2003, 18(6): 571

Abstract:The chlorfluazuron,a chitinase inhibitor acting on pest like a biological agent was selected for enhance Helicoverpa口, era nucleopolyhedrovirus(HaNPV)pesticide.The third instar larvae were infected with the virus mixed witI1 4.2ppm chlofluazuron,the LT50 value Was reduced to 2.44 days, while the larvae infected only with the virus,the LTso was 4.9O days,and only 4.2 ppm chlofluazum did not cause the larva death.TIle H V suspension formulation pesticide.which containing chlorfluazuron,Was produced in the factory.In field test,the 2nd or 4th generation larvae Was controlled by the viral pesticide,7 days after spaying the pesticide,the efi ciency were 85.2%,-,86.3% an d 69.6% —暑2.9% respectively,only slight efec t of the viral pe sticide on the nature enemi es Was observed .
Brief Reports

Genotyping of Hepatitis C Virus in Hebei Province

NIU Jian, XU Ruo, BAI Rui, TIAN Cha, ZHANG Li-ping, M ENG

2003, 18(6): 611

Abstract:Using nested RT—PCR an d type special primers of HCV,we performed genotype an alysis of HCV RNA from five representative cities in Hebei Province.Among 168 samples with HCV RNA,104 sera was typelb(61.9%),type 2a account for 22.6% (38/168),and lb/2a mixed—type was 15.5% (26/168).The results indicate that typelb is the dominance strain in Hebei Province.Compared with type 2a,type lb has important relationship with chronic hepatitis C.This study build 叩some foundations for diagnosis,treatment and vaccine study of hepatitis C.

Rapid M olecular Diagnosis of Concurrent Infection of Porcine Reproductive and Respiratory Syndrome an d Pseudorabies

XU Li, WANG Ling, SU Xin, WAN G, W U, CHEN Pu

2003, 18(6): 614

Abstract:According to the nucleotide sequences of Porcine Reproductive and Respiratory Synd rome V/ms VR2332 strain and Pseudorabies virus shan ghai strain provided in GenBank, two pairs of primersweredesignedto amplifytheN geneofPRRSV byRT—PCR an dTkgeneofPRV byPCR. As a result, a rapid molecular diagn osis with high specificity an d accuracy was set up.The result indicated that PRRSV Was detected from 11 out of 33 samples, PRV was detected from 9 out of 33 samples, and CO—infec tion by PRRSV an d PRV was confirmed in 8 samples, the rate of co-infection Was at24.2% .

A Possible Association of Virus Infection with Obesity

LI Ai-chun

2003, 18(6): 616