1995 Vol.10(1)
In this paper,a vaccinia vector pJE-RGN for co-expression of rabbies virus G and N protein was constructed.
cDNA probe of the partial genome segment of URV nineth gene was labelled with DIG by thetechnlque of PCR.DNA-RNA dot blot hybrid izat ion results showed the proporties of HRV A groupspeci ficity of this probe,The results were consistent by the method or loading the sam ple supornatantdirectly or loading after the extraction of fecal sample nucleic acld.We also compared the resul ts ofdot blot hybridlZation and PAG E.It was strongly ind icated in this ex periment that the Dig-labelledHRV cDNA probe prepared directly by PcR appeared to be convenient,fast,high labelling rate andhighly specific.
We analysed the BamHl EZ fragment of Epstein—Barr Virus in 21 cases of tissues from nas opha．ry'ngeal c~rcinoma(NPC)by polymerase chain reaction(PCR)and,r~quence analysis．The 2．99kb deletions within lhmHl EZ fragment were found in 1 1 sfm1DIes，the deletions wei'~similar to those 0f Raji
EBV which is latent in Burkitt s lymphoma．The BZLF1 gene of EBV locates within Bam HI EZ fragment an d has an impor~nt role in reproduc~ve cycle of EBV．Two point m utatioas were also found in the first exon of BZLFt gcne from a sam ple analyzed ，com pared to the standard B9S．8 EBV． The m uta
tions above may affect the latency~disrupting function of Epstein Barr Virus
In this study we evaluated the effects of four antisense oligodeoxynucl eotide phosphorothioates(ODN)asainst antigen expression of HBV gene,Four ODNs were synthesized with an average length of fifteen bases directed against the region upstream of the core gene initiation cedon(#1893-1907),against the region upstream and downstream of the polymerase codin8 gene initiation codon(#2297-2313,# 2797-2813),against the 3 region of 3.5 kb RNA for initiation of reverse transcription(#1817-l831).An ODN with random sequences was also synthesized as control.ODNs were tested agair1st HBV in both HBV transient and stable expressing systems.When being added to epG2 2.2.15 cells at 20 μmol/L every other day,compared to control,all our ODNs showed variable ex tent of inhibition on the expression of HBsAg.The inhibiting rates at day 4 were:C-ODN,24.5%;P-ODN,13%.PM-ODN,38.4%;PBS-ODN,28.4%,However all ODNs had no effect on the ex pression of HBeAg in th is cell line,After being cotransfected into the HepG2 cells with HBV DNA dime
Seventeen naturally occurring B strains of RSV selected directly from 73 strains circulating in nature． The ts character was exam ined by parallel plaque assay and reexam ined three times for each strain．Based oi"1 the 33℃ ／39．5℃ 1gPFU difference，the RSV circulating strains could be divided into three groups of strain，namely．Our study suggested that there a more naturally 0e curring ts strains arnmag the subtype B RSV than am ng subtype A(P< 0．05)，and the proportion of ts strab~s of RSV in oatu re was appro ximately the e from l987 to 1992． Prelim inary experiments showed tha t the rmruraily occurring ts strains of RSV are genetically stable．
In situ hybridization was used for detection of hantavirus RNA in the tissues of 1 9 cadavers with hemorrhagic fever w ith renal syndrome (HFRS) collected from different HFRS endemic foei in China． Viral RNA wiLq detec ted in a11 the 1 9 cases． It was mainly located in epithelial or parenchymal
ca lls of various organs with the positive cells in scattered，focal or wide distribution in the eases from Shaanxi and Shenyang，and in vascular endothelial cells of various organs as well as part of pa renchy real cells in the cases from Jiangxi，while in the case from Guangzhou．it was positive in focal necrotihe，alveolar sa ，renal interstit~l va u1a【urcs，etc．V RNA mainly I．oc,~liz．oci in the cytoplasms with ‰ rse grarlales orfine powdery specking staining．to a lesser extent also over cellular nucleus~ Besides．the po r,itive hybridization signals were also demonstrated in extrace linlar space~and oil RBC in some tissues and cases．The results suggest that hantavirus infection in human wz~ls ImntroDic and pred ilec tion for epithelial or endothelial cells an d th e latter may be caused by the difference of strain or scrotype of mfec ted virus，and may result to the variance in nathogenesis of HFRs．
The part of effects and characters of infection with Buzura suppressaria nuclear polyhedrosis virus(BsNPV)for Bs484 cells in the different media and cultural time were reported in this peper.The re sults showed that the types of media and the time after passage for Bs484 cells could produce distinct in-fluences on the rate of viral infection and the ytelds of polyhedra from BsNPV-infected Bs484 cells as ell as the other infective characters,The Bs484 cells of three days after psaseage simultaneously in the group of Grace media was a relatively pragmatic testing system of infection with BsNPV through expor imental comparision. In addition,this exporiment also found that the healthy hemolymph from the o-riginal insects could increase the cellular activity and the effects of viral infection.
The Lymantria,xylina Swinhoe cytoplasmic polyhedra xhows a quite difference ranging from 0.8 to2.lμm in diameter.The virions were randomly distributed in a polyhedron;The virions show icosahedron, and about 60 nm in diameter with l2 spikes.By the analysis of SDS-PAG E,the polyhedral pro-teins contain one major band(31000 Dalton)and three minor tsands.The virlon has 6 polypoptidesranging from 12600 to 33000 Daltons,The protein from LxCPV is rich in aslxirtic acid,glutamic acidand tyrosine,but poorer in cystein and methionine; The ratio of basic amino to acidic amino is l.43.By the stability test of the LxCPV RNA to RNase ,DNase and formaldehyde,the staining reaction ofacridine orange,the RNA is demontrated as double-strand RNA(dsRNA)with a Tm of 87℃.TheRNA genome consists of ten molecular mass from 2.46 to 0.35 MD,and with a totol estimated moleeular mass of l4.42 MD,Three distributive peaks of LxCPV RNA segments contour length are foundat 0.5μm,1.0μm and l.3μm respectlvely by electron micrcacopic analysis.
The cDNA of potato leafroll virus coat protein gene and cDNA by random primer were used as probe labeled with 32p by nick translation.
A virus isolate(B一935A)from faba 13e2．n w collected in Hangzhou．Zhejiang province．The isolate could infect 1 2 plant species in tkrce families． On faba bean，the isolate produced mosaic symptoms and necrosis．Its thermal inactivaflon point was 85— 90℃ ，dilution end po int was 1 0一一1 0 ．The virus particles wore rod—shaped with the length of 300nm ． The capsid protein of B一935A containod one po lypeptide with molecular weight of 1 7500．Th e viral genon~ consisted single strand RNA with the approximate length of 6．4kb． 1m muno-serological electron m icroscopy r ISEM ) and agro
ge1 double diffusion test showed B一935A strongly reacted with the antisera of TMV． On the basis of these characteristics the B一935A w／Is identified lis a faba bean sCraM of TM V．This is the first report of TIVlV on faba bean and first repo rt ofTM V on legum inous cropsin China.
The morpho8enesis of bovine viral diarrhca virus(BVDV)strain Oregon C24V in bovine testiscell culture was exam ined by electron micraseopy,Virions were roughly round and approx imately 50nm in diameter with a 30nm core,Virus replication took piace within cytoplasm of hcot cells. Budding of BVDV through membrane of medified rough endoplasmic reticulum was obeer ved.The virusmight be released by exocytosis or by disintegration of the vacuoles containing virus after cell death.
The sixth stadium larvae of massonpine caterpillar in the overwintered,first and third generationswere infected with CPV of Dendrolimus spectabilis at the same ineeulation of 1×107 PIB/ml in forest.The results suggested that the larvae of overwintered generation could be chosen as the best carrier forvirus large preduction, and the stage, when the midgut was fully infected and became yellow or whitein color,was the optimum poried for collection.
This paper reports that EHFV were isolated from the larvae of the m ites which have no biting and the sucking nⅡce bitter by these ae could be infected with EHFv、It showed tl-,at these |arvae Disess natural infection of EHFV and can spread EHFv by biting ．furthermore．the EHFV of the lar
Vae natural infection may a．Jly be spread over by eggs．The results showed that ， n(L．)wo are has an impor~ ．L role in sprea ding EⅧ by rats and in the maintenance of the epidemic focas area．
