OBJECTIVE To investigate the present situation of hand-washing among medical staff then explore more suitable hand-washing methods and monitoring measure. METHODS By surveying the hand-washing situation of 96 medical staff in our hospital through the method of sampling,the different germ eradication rate between routine soap hand-washing and disinfectant wet towel hand-wiping as well as hand-washing rate in all candidate population during practical work were observed. RESULTS The germ eradication rate after routine soap hand-washing was 86.0%,while by disinfectant wet towel wiping it was increased to 91.3%.The washing rate after above former method was 18.3% and after above two methods combined was increased to 43.6%,and after health propaganding and training was up to 60.6%. CONCLUSIONS Disinfectant wet towel hand-wiping is convenient,practical and effective which would be more suitable for clinical practice when combined with routine soap washing method.

Objective To study the influence of sunscreens with different efficacy on delayed type hypersensitivity (DTH) and their immunoprotective effect in mice.Methods A cohort of mice were randomly divided into 5 groups with 10 mice in each group:group 1 as the positive control without irradiation,group 2 receiving solar-simulated radiation (SSR) only,group 3 receiving SSR and protected by sunscreen l with sun protection factor 15(SPF15)and persistent pigment darkening(PPD)12,group 4 receiving SSR and protected by sunscreen 2 with SPF 50 and PPD 28,and group 5 as the negative contml receiving SSR only.SSR was carried out on the back of mice with the UVA dose being 1.4 J/cm2 and UVB dose being 100 mJ/cm2 for 10 days.After a 5-day irradiation,the groups 1 to 4 were immunized by intraperitoneal injection with 100 μl(107 cells/ml) of Candida albicans suspension.On the 10th day both sides of the posterior foot pad were measured;then the foot pads were injected with additional 50 μl of the Candida albicans suspension.Twenty-four hours after the injection,the thickness of each foot pad was measured,and immunosuppression rate was calculated.Finally,the mice were sacrificed and skin samples were obtained from the back of these mice followed by the examination of CDla, CD80 and CD86 expression by Western blot.Resets The thickness of edema in foot pads was 0.41±0.38 mm,0.21±0.23 mm and 0.30 ± 0.25 mm in group 1,3 and 4,respectively,significantly higher than in group 5 and 2(0.04±0.03 mm,0.14±0.12 mm,respectively,all P<0.05),while no significant difference was observed between the group 3 and 4(P>0.05).Significant differences were observed in the immunosuppression rate between group 2,3 and 4(73.0%±11.3%,54.1%±6.4%,29.7%±7.5%,respectively,all P<0.01).Western blot revealed a significant increment in the expression of CDla protein in group 1 compared with group 2 as well as in the expression of CD86 protein in group 1 and group 3 compamd with group 2 and group 5(all P<0.05),but no statistical difference was observed between the other groups in the expression level of CDla,CD80 or CD86(P>0.05).Conclusions The exposure to sub-erythema dose of UV can induce DTH,and sunscreens have an immunoprotective effect in this process.Epidermal Langerhans cells are not essential for UV-induced immunosuppression.

Objective To investigate the drug-resistance of Staphylococcus aureus induced by erythromycin in vitro and its changes in growth and susceptibility of antibiotics.Methods Erythromycin in vitro induction was conducted with the S.au-reus reference strain ATCC25923 on the serial of erythromycin agar plates.The growth of S.aureus,and the susceptibility a-gainst other antibiotics was compared after induced to the parent strain.Results Resistance to erythromycin was successful-ly,and themaximum MIC was over 256 mg/L.The Erythromycin-resistant S.aureus grew much slower than the susceptible parent,and the strains didn’t have cross-resistance to other antibiotics.Conclusion S.aureus could be induced resistance in vitro by erythromycin,and this resistance inherited stably.Some phenotype and biochemical characteristic features of the strain were changed after induced.

Objective To evaluate effects of tea polyphenols on the mRNA and nucleoprotein expression of Nrf2/Bach1 in human skin fibroblasts (HSFs).Methods Some HSFs were incubated with tea polyphenols at different concentrations of 0,2.5,5,10,20 and 40 mg/L for 24 hours.Methyl thiazolyl tetrazolium (MTT) assay was conducted to evaluate the proliferative activity of HSFs to screen the optimal concentration of tea polyphenols.Then,some other HSFs were treated with tea polyphenols at this optimal concentration for 24 hours.Real-time quantitative PCR (RT-qPCR) was performed to determine mRNA expression of Nrf2 and Bach1,Western blot analysis to measure nuclear expression of Nrf2 and Bach1 proteins,and immunofluorescence assay to determine the distribution of Nrf2 and Bach1 protein in the cell nucleus.Results MTT assay showed that 5 mg/L tea polyphenols had no obvious effects on the proliferation of HSFs,so 5 mg/L was chosen as the optimal concentration of tea polyphenols for subsequent experiments.HSFs cultured without tea polyphenols served as control group.After the treatment,the 5-mg/L tea polyphenol group showed significantly decreased mRNA and nuclear protein expression of Bach 1 (mRNA:0.629 ± 0.077 vs.0.940 ± 0.033,t =6.397,P ＜ 0.05;protein:1.424 ± 0.171 vs.16.966 ± 1.702,t =15.730,P ＜ 0.05),but significantly increased mRNA and nuclear protein expression of Nrf2 (mRNA:1.467 ± 0.076 vs.0.977 ± 0.091,t =7.133,P ＜ 0.05;protein:6.929 ± 0.121 vs.3.537 ± 0.126,t =33.636,P ＜ 0.05) compared with the control group.Immunofluorescence assay showed increased accumulation of Nrf2 protein,but decreased accumulation of Bach1 protein in the nucleus.Conclusion Tea polyphenols can promote the mRNA and nuclear protein expression as well as nuclear distribution of Nrf2,but suppress the mRNA and nuclear protein expression as well as nuclear distribution of Bach 1,finally exerting antioxidative effects.

Objective To evaluate the scavenging effect of crude polysaccharides extracted from Lycium barbarum (LBP) on reactive oxygen species in ultraviolet radiation-induced HaCaT cells,and to explore its possible mechanism.Methods Cultured immortalized human keratiuocyte HaCaT cells were divided into 6 groups:blank control group receiving no treatment,LBP group treated with crude LBP alone,ultraviolet A (UVA) group treated with UVA radiation alone,ultraviolet B (UVB) group treated with UVB radiation alone,UVA + LBP group treated with crude LBP for 24 hours followed by UVA radiation,and UVB + LBP group treated with crude LBP for 24 hours followed by UVB radiation.MTT colorimetry was performed to evaluate the cellular proliferative activity,UV spectrophotometric method to measure the UVA and UVB absorption of crude LBP,dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescent probe assay to detect the level of ROS,enzymatic-biochemical method to estimate the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px),as well as to detect the leakage of lactate dehydrogenase (LDH).Results Crude LBP at different concentrations of 0,100,200,300,400,500,600,1 500,2 000 mg/L had no obvious effects on the proliferative activity of HaCaT cells.Crude LBP had a high transmittance of ultraviolet rays at 280-400 nm.Compared with the blank control group,the UVA group and UVB group both showed significantly higher LDH leakage and ROS level,lower activities of SOD and GSH-Px (P ＜ 0.001 or 0.05).Pretreatment with crude LBP before the ultraviolet radiation could significantly increase the activities of SOD and GSH-Px,decrease the LDH leakage and ROS level in the UVA + LBP group and UVB + LBP group compared with the UVA group or UVB group (P ＜ 0.05).Conclusion Crude LBP have no effect of sunscreening agents,but can effectively scavenge ROS,decrease LDH leakage,inhibit ultraviolet radiation-induced photodamage in HaCaT cells,which may be associated with the enhancement of antioxidant enzyme activity.

After sequencing the Asia 1 foot-and-mouth disease virus (FMDV) (As01 strain), we amplified the two fragments covering the whole genome by overlapping PCR and long PCR. The 5' fragment was 1.8 kb in length including 15Cs, and the 3' fragment was 6.7 kb in length. The two fragments were cloned into the pBluescript SK vector to construct recombinant plasmid pBSAs carrying the full-length cDNA of FMDV As01 strain. The RNA transcript was synthesized in vitro using T7 polymerase and transfected into BHK-21 cells. We observed the typical CPE caused by rescued FMDV. The harvested virus was confirmed to be Asia 1 FMDV by RT-PCR, indirect immunofluorescence assay (IFA) and electron microscope observation. The rescued virus showed a similar pathogenicity in suckling mouse (LD50) compared to its wild-type virus. The infectious cDNA clone of the FMDV As01 strain laid a new ground for further investigation of FMDV virulence determinants and development of novel vaccines against FMD.
3' Untranslated Regions ; 5' Untranslated Regions ; Animals ; Base Sequence ; Cattle ; Cell Line ; Cloning, Molecular ; DNA, Complementary ; genetics ; Foot-and-Mouth Disease ; metabolism ; virology ; Foot-and-Mouth Disease Virus ; classification ; genetics ; growth & development ; Genome, Viral ; Mice ; Molecular Sequence Data ; Plasmids ; RNA, Viral ; genetics ; Transfection ; Virulence ; Virus Replication

Objective To investigate the dynamic changes of three types of anti-poliovirus neutralizing antibodies and anti-hepatitis A virus (HAV) IgG antibody in children who were immunized with inactivated enterovirus 71 (EV71) vaccine (human diploid cell).Methods Serum samples were collected from the subjects immunized with inactivated EV71 vaccine.Neutralizing antibodies against EV71 and poliovirus were detected by micro-cytopathic effect neutralization test.Enzyme linked immunosorbent assay (ELISA) was used to detect IgG antibody against HAV.Results The geometric mean titers (GMTs) of anti-EV71 neutralizing antibody increased to 4.85 following the first-dose injection of inactivated EV71 vaccine.A significant increase of GMTs (up to 64.37) could be observed 28 days after the second-dose vaccination.Meanwhile, results of the dynamic monitor showed that there were slight fluctuations in the neutralizing antibodies against three types of poliovirus on day 28 (28 days after the first-dose vaccination) compared with those on day 0 (before vaccination) (P<0.05);types Ⅰ and Ⅲ anti-poliovirus neutralizing antibodies on day 56 (28 days after the second-dose vaccination) remained slightly different from those on day 0 (P<0.05), but type Ⅱ anti-poliovirus neutralizing antibody on day 56 had restored to normal level (P>0.05).The level of anti-HAV IgG antibody was stable and no significant difference was found during the observation period (P>0.05).Conclusion This study shows that inactivated EV71 vaccine has no impact on anti-HAV IgG antibody in Children during the two-dose vaccination and in anti-EV71 antibody-producing period, but has slight influence on the anti-poliovirus antibodies.In general, changes in antibody profile do not affect the clinical efficacy of immune response.

Objective To investigate the protective effect of lycium barbarum polysaccharide (LBP) on DNA damage of HSF cells induced by UV.Methods We established the model of UV induced photo damage in HSF cells.We detected the viability of HSF cells by using MTT colorimetry.The UV absorption spectrum of LBP was also measured by UV spectrophotometer.The level of ROS was detected by DCFH-DA fluorescent probe method.Comet assay was employed to evaluate the DNA strand breakage damage.Results When the concentration of LBP was less than or equal to 300μg/ml,there was no significant effect on the proliferation of HSF cells (P＞0.05).When the concentration was more than 300 μg/ml,it could inhibit the cell proliferative activities (P＜0.05).Compared to the UV groups,UV+LBP groups can respectively improve the cell proliferation activity (P＜0.05).The absorbance was slight range 280 from 400 nm.Compared with the UV group,the relative fluorescence intensity and the migration distance of UV+ LBP groups were significantly decreased (P＜0.05).Conclusions Lycium barbarum polysaccharide can effectively inhibit the proliferation activity and protect the breakage of DNA strand induced by UV,which is probably due to its action of removing free radicals.