Since 2000,most of H5N1 subtype influenza A virus had a unique mutation of NS gene with 15base pair deletion from 263 to 277. In order to investigate the bio-characteristics of this mutation,two different NS recombinants,RWSN-248 and RWSN-m248,were generated via plasmid rescue from A/WSN/33(H1N1) and A/SD/04(H5N1). RWSN-248 had a higher viral titer than RWSN-m248 in MDCK and COS-1 cells that have an IFN response,but they had the similar growth ability in Vero cells that lack an IFN response. Both of two recombinants grew well in embryonated chicken eggs and had the similar viral titer and MDT. The results above revealed that the deletion from 263 to 277 sites of NS gene did not influence viral virulence to but decreased viral anti-IFN ability of H5N1.

Air ; Humans ; Workplace

Aged ; Humans ; Male ; Pharyngeal Neoplasms ; Polyps ; Pyriform Sinus ; pathology

To standardize the harvest ways of Dendrobium officinale and improve the quality and yield of D. officinale, a field experiment was carried out to study the effect of two kinds of harvest ways, which were keeping some of the axial shoot and harvesting all of the shoot by the end of the year. Then, the agronomic traits and yield were measured and the contents of polysaccharides and extractum were determined. The results showed that the harvest ways significantly affected the growth of D. officinale. Keeping some of the axial shoot could significantly improved the number of sprout, stem length, internode number and the internodal length, which also triggered increase the weight of fresh stems, leaves and the total of them and dry stems in per unit area, but it could not promote the stem diameter and the polysaccharide content in stems. Keeping some of the axial shoot moderately was conducive to the improvement of the production of medicinal materials in the process of harvesting by promoting the germination and growth of new buds, and to ensure the polysaccharide content by regulating the illumination and the density of cultivation.
Agriculture ; methods ; Dendrobium ; chemistry ; growth & development ; Drugs, Chinese Herbal ; analysis ; Plant Leaves ; chemistry ; growth & development ; Plant Stems ; chemistry ; growth & development

The high-copy-number plasmid pcDNA3.1+ is unstable within S almonella typhimurium. A novel plasmid pmcDNA3.1+ was constructed by removin g the promoter sequence of ampicillin resistance gene (bla gene) in plasmid pcDNA3.1+. In contrast to pcDNA3.1+, pmcDNA3.1+ was stable within Salmonel la typhimurium SL7207 in LB medium with or without ampicillin. Further experi ments showed the ?-lactamase activity of Salmonella typhimurium SL7207(pmc DNA3.1+) was apparently lowered than that of Salmonella typhimurium SL7207( pcDNA3.1+) and the high ampicillin concentration was maintained longer in LB me dium culturing Salmonella typhimurium SL7207(pmcDNA3.1+). When mice were a dministered with Salmonella typhimurium SL7207(pmcDNA3.1+) intraperitoneall y, more than 95% of Salmonella cells separated from the spleen still harbore d the plasmid pmcDNA3.1+ 7 days later; but 99% of Salmonella cells lost the plasmid pcDNA3.1+ at day 3 in mice innoculated with Salmonella typhimurium SL7207(pcDNA3.1+). By lowering the expression of bla gene, the rapid deco mposition of ampicillin in LB medium was avoided and the metabolic pressure was relieved for the host cells. This method offers a solution for the problem of t he instability of high-copy-number plasmid within Salmonella typhimurium.

BADH-CMO double gene,CMO gene and DREB1A gene were transformed respectively to embryonic callus of Kentucky bluegrass by particle bombardment. Then the embryonic callas of kentucky bluegrass were put in meclium for subculture which is mixed with 100mg/L hygromycin and the meclium for plantlet regeneration which mixell with 50mg/L hy gromycin about one month. Thus,the hygromycin-selectecl plants were obtained and were transplantecl into tlowerpots. The results of the PCR and Southern blot analysis indicated that the DREB1A gene,CMO gene and BADH-CMO double-gene were integrated into the genomic DNA of Kentucky bluegrass.

With the constant rise of energy price,it has a great practical meaning of using lignocellulose to produce ethanol.Xylose is a kind of monosaccharide whose content is only less than glucose in most lignocellulosic hydrolysates.There is some difficulty of producing ethanol from lignocellulose by the traditional ethanol production strain Saccharomyces cerevisiae,because it cannot metabolize xylose.People have tried to use genetic engineering technology and cell fusion method to modify Saccharomyces cerevisiae to make it metabolize xylose and produce ethanol for many years.This review indroduced the progress in this field.

Objective To explore the sensitivity and accuracy of directly sequenced core and non-structrural protein (NS)5B regions for hepatitis C virus (HCV)genotyping.Methods Fifty-one serum samples from chronic hepatitis C patients were collected in the study.Reverse transcription-polymerase chain reaction was used to amplify core and NS5B regions.Genotypes or subtypes were determined by the phylogenetic analysis of directly sequenced core and NS5B regions.Results Among the 51 samples,49 (96.1 %)were successfully typed by phylogenetic analysis of directly sequenced core region.There were overall five genotypes determined in the area,including 1b (61 .2%,30/49 ),2a (20.4%,10/49 ),2b (2.0%,1/49),3a (4.1 %,2/49 )and 6a (12.2%,6/49 ).The positive rate of HCV genotying was 88.2% (45/51 )on the basis of NS5B region.HCV genotypes 1b,2a,2b,3a and 6a were found in 62.2% (28/45),20.0% (9/45 ),2.2% (1/45 ),4.4% (2/45 )and 11 .1 % (5/45 )of the patients, respectively.Conclusion The HCV genotyping based on core regions,compared with that based on NS5B,shows the advantages of primer design,amplification efficiency and accuracy,suggesting that it has the priority to be used in the epidemiological and clinical study of HCV genotyping.

Background Epidemiological investigation in human has been conclusive. In postmenopausal women,the incidence of cataract is higher than men at the same age. In addition,hormone replacement therapy may protect against the development of cataract. However,this role of androgen is not clear. Objective This study was to explore the effects of estrogen and androgen on anti-oxidative ability of lens after ovariectomy. Methods Fifty-six three-month-old clean female Wistar rats were randomly divided into normal control group,sham operation group, castration group,estrogen eyedrops group;estrogen injection group;androgen eyedrops group;androgen injection group and 8 rats for each. Ovariectomy was performed in the rats of castration group and gonadal hormone application group, and estradiol benzoate solution or testosterone propionate solution were utilized topically or systemly in 5 months after ovariectomy for 6 weeks respectively. Only abdominal cut was curried out in sham operation group. The lenses of rats were examined weekly under the slit lamp. The serum estrogen and androgen levels of rats were detected before,after operation and 6 weeks following the administration of gonadal hormone. The contents of superoxide dismutase( SOD) , glutathione( GSH) ,malondialdehyde( MDA) and water-soluble protein ( WSP) in rat lens homogenate were detected at the end of the experiment. Utilization of animals complied with the Regulation for the Administration of Affair Concerning Experimental Animals by State Science and Technology Commission. Results No opacity of lenses was found during the experiment duration in various groups. The serum estradiol levels of rats in sham group were insignificantly different from normal groups in various time points( P>0. 05). The evident decline of serum estradiol was detected in the rats of castration group and gonadal hormone application groups compared with sham group in 5 months after operation( all P<0. 01). However,at the sixth weeks after the system use of estradiol or testosterone,the serum estradiol levels were significantly higher than the castration group and topical application groups of gonadal hormone(P<0. 01). The contents of SOD,GSH and WSP in lenses were considerably increased,but the MDA level in lenses was decreased after system use of estrogen ( P<0. 01). The activity of SOD and GSH were lower after system use of testosterone in comparison with castration rats ( P < 0. 05 ). Conclusion Estrogen can protect lens against oxidation damage. However, androgen, to a certain extent, may contribute to the development of oxidative damage in OVX female rats.

The study reports the detection of neuroprotective effect of 10 kinds of coumarin derivatives and explores their possible mechanism. MTT method was used to screen the neuroprotective effect of 10 coumarin derivatives on neurotoxic agents (Aβ25-35 and rotenone) or OGD (oxygen-glucose deprivation). A compound with better protective effect was obtained. Then the effect of this compound on neurotoxic agents on PC12 was detected by the morphological observation. Furthermore, the effect of compound 3 on microglia with lipopolysaccharide (LPS) induced inflammation was detected. And the inflammatory factor was tested. Finally, direct free radical scavenging ability was detected. Compound 3 was found to be the best compound through three neurons toxic models. Not only compound 3 ameliorated cell viability reduced by three neurons toxic models, but also significantly inhibited the production of inflammatory factor (TNF-α and IL-1β). And its free radical scavenging ability is very good, especially the effect on superoxide anion, which is comparable with vitamin C. The significant scavenging effect of compound 3 on superoxide anion might be the mechanism of the neuroprotection. Compound 3 as a potential neural cell protective agent merits further investigation.
Animals ; Coumarins ; chemistry ; Free Radical Scavengers ; chemistry ; Inflammation ; Microglia ; drug effects ; Neurons ; drug effects ; Neuroprotective Agents ; chemistry ; PC12 Cells ; Rats