An exogenous avian leukosis virus (ALV) strain SDAU09C1 was isolated in DF-1 cells from one of 240 imported 1-day-old white meat-type grand parent breeder chicks. Inoculation of SDAU09C1 in ALV-free chickens induced antibody reactions specific to subgroup A or B. But gp85 amino acid sequence comparisons indicated that SDAU09C1 fell into subgroup A; it had homology of 88.8% - 90.3% to 6 reference strains of subgroup A, much higher compared to other subgroups including subgroup B. This is the first report for ALV of subgroup A isolated from imported breeders.

Objective To explor the ultrasonography methodology of the fetal ductus arteriosus.Methods Based on the fetal four-chamber sight, the characteristic ultrasound images were observed by moving probe,such as "V-shape" sign,"three-finger" sign,"Z-shape" sign and"hockey-handle" sign making up of the ductus arteriosus and the nearby structures were observed by moving probe. The inner diameter,the systole flow velocity,the diastole flow velocity and the resistance index of the ductus arteriosus via the "V-shape" sign section were measured. Results Among the 365 normal fetus cases,355 "V-shape" sign cases,237 "three-finger" sign cases,298 "Z-shape" sign cases and 331 "hockey-handle" sign cases were identified. The inner diameter of the fetal ductus arteriosus increases gradually with the growth of the gestational weeks and the flow velocity increases gradually too, while the resistance index had no obvious variation with the growth of the gestational weeks. Conclusions According to the characteristic ultrasound images, such as "V-shape" sign, "three-finger" sign, "Z-shape" sign and "hockey-handle" sign, the fetal ductus arteriosus can be identified promptly.

Objective To understand the prevalence of HIV infection,syphilis and hepatitis C and related behavioral factors in female sex workers (FSWs) and other 6 risk populations in Tibet Autonomous Region.Methods A cross-sectional survey was conducted among 2 000 FSWs,200 men who have sex with men (MSM),200 drug users,1 200 male migrants,5 600 young students,as well as hospital patients and pregnant women in Lhasa,Qamdo,Nyingchi,Xigaze Shannan,Ali and Nagqum from June to December 2015.Face to face interviews were conducted to collect their demographic and behavioral information,and blood samples were collected for the tests of HIV,syphilis and hepatitis C virus (HCV) antibodies.The enumeration data were described by using rate and constituent.Results A total of 20 597 participants were involved in cross-sectional survey.The positive rates of HIV and syphilis antibodies were 5.81％(124/2 133) and 0.05％ (1/2 133) respectively among FSWs.The positive rates of HIV and syphilis antibodies were the same (9.80％,10/102) among MSM.There were no HIV infection detected in among drug users,male migrants and young students,but the positive rates of syphilis antibody were 4.00％(4/100),0.33％ (4/1 297) and 0.08％ (4/5 095)respectively.The positive rates of HIV and syphilis antibodies were 0.04％(2/5 565) and 1.64％(91/5565) among hospital patients.The positive rates of HIV and syphilis antibodies were 0.11％(7/6 305)and 1.19％(75/6 305)among pregnant women.The positive rates of HCV antibody were 1.00％ (1/100)among drug users and less than 0.50％ in other risk populations.The overall consistent condom use rate was low.Conclusions In Tibet,HIV infection mainly occurred in the MSM,syphilis mainly occurred in FSWs and MSM,HCV infection mainly occurred in drug users.The AIDS related knowledge awareness rate was low in these risk populations,and less of them received intervention service.

Objective To explore the HIV epidemic and related factors among MSM in Jilin province.Methods During the implementation of sentinel surveillance program from 2010 to 2015,continuous cross-sectional studies were conducted to monitor the awareness of AIDS,sexual behavior,HIV and syphilis positive rates,with the sample size no less than 400 in each surveillance site.Results From 2010 to 2015,a total of 7 823 MSM were involved in this study.The overall HIV prevalence among MSM was 5.4％ (42/7 823),with an increasing trend during 2010 and 2015 (Trend testx2=110.023,P＜0.001).The rates of awareness on AIDS were higher than 90.0％.The proportion of consistent condom use was 27.0％ (2 112/7 823) in the last 6 months,and significant differences were found in these years (x 2=234.038,P＜0.001).Results from multivariate logistic regression analysis showed that the HIV infection related risk factors among MSM in Jilin province would include:residency from other provinces (aOR=1.797,95％ CI:1.185-2.726),recruitment through internet (aOR=1.717,95％CI:1.332-2.215),diagnosed of having sexually transmitted diseases in the previous year (aOR=1.893,95％CI:1.356-2.643) and positive testing on syphilis (aOR=4.309,95％CI:3.097-5.995).And consistent condom uses in the last 6 months (aOR=0.387,95％CI:0.143-0.557),tested HIV in the last year (aOR=0.632,95％CI:0.375-0.891) were preventive factors.Conclusions HIV prevalence was increasing among MSM in Jilin province,but both the proportion of consistent condom use and the former HIV testing rate were at a low level.Aggressive measurement including consistent condom use and periodical HIV testing among MSM was warranted.

Objective: To investigate cardiovascular disease (CVD) prevention status among residents with intra-urban migration in Central China, so as to provide insights into targeted prevention and control of CVD. Methods: Basic data of residents aged 35 to 75 years who participated in Early Screening and Comprehensive Intervention Project for CVD high-risk populations in Central China from September 2015 to August 2020 were collected. According to birth place, type of registered residence and current residence, residents were divided into four groups: local residents in old urban area, local residents in new urban area, other urban migrants and other rural migrants. The status of CVD primary and secondary prevention, were analysed by using a robust Poisson regression model. Results: A total of 76 513 residents were recruited, including 29 420 males (38.45%) and 47 093 females (61.55%), and had a mean age of (56.36±9.84) years. There were 45 087 (58.93%) local residents in old urban area, 23 868 (31.19%) local residents in new urban area, 5 668 (7.41%) other urban migrants and 1 890 (2.47%) other rural migrants. After adjusting for variables such as age, gender and educational level, the results of robust Poisson regression analysis showed that compared with local residents in old urban area, local residents in new urban area had lower compliance rates of non- or moderate-drinking (RR=0.987, 95%CI: 0.975-1.000) and healthy diet (RR=0.535, 95%CI: 0.365-0.782), lower proportion of using aspirin as primary prevention in CVD high-risk population (RR=0.616, 95%CI: 0.511-0.741), lower awareness (RR=0.873, 95%CI: 0.782-0.974) and control rates (RR=0.730, 95%CI: 0.627-0.849) of hypertension; other urban migrants had higher compliance rate of non-smoking (RR=1.045, 95%CI: 1.017-1.075); other rural migrants had lower proportion of using aspirin as primary prevention in CVD high-risk population (RR=0.826, 95%CI: 0.707-0.966). Conclusion The CVD primaryprevention among local residents in new urban area is relatively poor among four groups of residents in Central China, and key interventions are needed.

Objective To analyze the serological results and sexual behavior among different types of drug users (DUS) at the HIV sentinel surveillance sites.Methods Sentinel surveillance programs were conducted between April and June annually.DUS were those involved in custodies,living at the communities and those attending the methadone maintenance treatment clinics but with positive urine tests one month before blood sampling collected and questionnaire survey started.Results 116 279 drug abusers were included in the analysis.The prevalence rates of HIV,Syphilis and HCV among traditional drug(heroin,etc.)users were 5.0％,4.4％ and 49.4％,while the prevalence rates of new narcotic (meth,etc.) users were 0.5％,4.6％,15.2％,respectively.The prevalence rates of HIV,syphilis among traditional drug uses were higher than the new narcotic users (P＜0.01).The proportion of sexual behavior in last month and the proportion of sexual behavior with casual and commercial sexual partners were 46.3％,87.2％ and 28.1％ among the new narcotic users,respectively,which were higher than those among traditional drug users (40.7％,82.8％ and 22.2％).The proportion of using condom in last sexual contact with casual sexual partner was 33.3％ among the new narcotic users which was less than traditional drug users (36.2％).The proportion of condom use in the last commercial sexual contact was 65.l％ which was higher than those traditional drug users (62.9％).The proportion of never using condom with casual and commercial sexual partners in the past year was 43.2％ and 19.0％ among the traditional drug users,which were higher than those among new narcotic users (41.3％,15.3％).Conclusion Compared with the traditional drug abusers,the sexual behavior of new narcotic users seemed more active,less engaging in condom use but with higher risk of HIV transmission through sexual contact.

OBJECTIVETo develop a RT-PCR method for a rapid and sensitive detection of Salmonella in poultry samples.

METHODSThe RT-PCR method was established and its specificity was testified on the basis of invA gene. Serial 10-fold diluted pure suspension culture of CMCC 50041 was detected by RT-PCR, the standard curve was constructed and the amplification efficiency was calculated. Artificially contaminated experiment was done, six artificially-inoculated samples containing final concentration of Salmonella CMCC 50041 (1, 10, 10(2), 10(3), 10(4), 10(5) and 10(6) CFU per 25 g poultry samples) were prepared respectively. All the samples were incubated for 0, 4, 8, 12 and 18 h and the DNA was extracted for RT-PCR detection, meanwhile by PCR detection and the traditional method. The sensitiveness and specificity were compared among the three methods. At the same time, 16 samples of retail whole poultry were collected from markets and detected by the above three methods as well, and thereby to further compare the positive detection among the three methods.

RESULTSThe established RT-PCR method was specific for the detection of Salmonella. The sensitivity was 5.2×10(3) CFU/ml for pure Salmonella culture without enrichment. Correlation coefficients of standard curves constructed using the Ct versus log value of concentration of Salmonella showed good linearity over a 8-log dynamic range (5.2×10(3)-5.2×10(10) CFU/ml), with the R(2) at 0.999. RT-PCR detection limit for artificially contaminated samples after enriching for 12 h was 1 CFU/25 g sample, which was the same with the limit of PCR and 10 times more sensitive than the limit of traditional method. Standard curve of sample after enrichment for 12 h was established. Seven of 16 samples were detected positive by RT-PCR, which were also tested positive by PCR, while only five samples were positive by traditional method. The positive ones were quantitatively analyzed using standard curve of sample and determined the initial Salmonella numbers of CFU/25 g.

CONCLUSIONThe established RT-PCR technology was simple, rapid, sensitive and specific, which was suitable to quickly detect Salmonella in poultry samples.

Objective To understand the trends on HIV and syphilis infections,as well as on risk behaviors and intervention among MSM in China from 2010 to 2013 so as to provide information for the development of intervention strategies for MSM. Methods Study population involved MSM who were recruited for the national HIV sentinel surveillance between 2010 and 2013. Demographic information,HIV related risk behaviors,and results on HIV and syphilis infections were described and trend analysis was performed. Results Between 2010 and 2013,the total number of MSM under survey was 149 848. As for sources of the studied population,12.3% of them were from public bathrooms (Group A),30.1% from internet (Group B),and 57.5% were others (Group C). Proportions of three groups were similar between 2010 and 2013. The proportion of always using condom in the last six months increased from 30.2%to 37.8%,from 34.7%to 42.9%and from 35.3%to 43.1%in group A,B or C( trend:P<0.01),from 2010 to 2013. The proportion of using condom in group A was the lowest among the three groups. The prevalence rate of HIV increased from 7.8%in 2010 to 9.2%in 2013 among group A,from 5.0%in 2010 to 6.8%in 2013 among group B,from 5.6%in 2010 to 6.5%in 2013 among group C(trend:P<0.01). The prevalence rate of syphilis decreased from 13.2% in 2010 to 9.5% in 2013 among group A,from 6.1% in 2010 to 5.7% in 2013 among group B,from 8.7% in 2010 to 6.2% in 2013 among group C (trend:P<0.01). In this MSM population,77.1%of them were at age 21-40,9.4%were at age 41-50 and 2.8%were older than 50 years of age. Both the prevalence rates of HIV and syphilis were the highest-10.1%and 13.6%,among age group of over 50s,respectively. Conclusion HIV prevalence among MSM increased rapidly in the last four years,especially in older age groups and from public bathrooms. More intervention efforts should be targeting on MSM with the above mentioned characters.

A chronic refractory wound is caused by continuous skin damage. At the same time， it may be formed due to repeated infection， vascular insufficiency， diabetes， tumors， chronic osteomyelitis， and other reasons， resulting in wound repair interruption and recovery delay. Chronic refractory wound seriously affects the quality of life of patients and consumes a lot of medical resources. Polysaccharides in traditional Chinese medicine （TCM） are the effective components of most TCM. Modern pharmacological studies have found that polysaccharides contained in TCM have anti-inflammatory， antioxidant， anti-radiation， hypoglycemic， antiviral， anti-tumor， hypolipidemic， and immunomodulatory effects. Through the summary and analysis of the literature， it was found that the mechanism of polysaccharides in TCM to promote chonic refractory wound repair was mainly realized from the following aspects： firstly， regulating inflammatory cytokines like interleukin-4 （IL-4）， interleukin-10 （IL-10）， interleukin-8 （IL-8）， and tumor necrosis factor-α （TNF-α） or regulating macrophage-related inflammatory proteins and chemotactic proteins like MIP-2， MCP-1， to shorten the inflammatory period. Secondly， activating growth factors like platelet-derived growth fator （PDGF）， basic fibroblast growth factor （bFGF）， TGF-α， and vascular endothelial growth factor （VEGF） to recruit endothelial cells and fibroblasts into tissue proliferation. Thirdly， activationg VEGF and its downstream receptor vascular endothelial growth factor receptor-1 （VEGFR-1） and vascular endothelial growth factor receptor-2 （VEGFR-2）-mediatated protein kinase C/extracellular regulated kinases （PKC/ERK） signaling pathway or promoting angiogenesie and improving wound blood flow through angiotensin （ANG）. Fourthly， promoting the ablility of collagen synthesis by enhancing the secretion of hydroxyproline and hyaluronic acid （HA） from fibroblasts （FB） and regulating relevant matrix metalloenzymes and their enzyme inhibitor to regulate the extracellular matrix. Fifthly， eliminating free radiccals to reduce the damage caused by oxidative stress to tissue. Sixthly， enhancing the phagocytic ability of macrophages， the activity of natural killer cells， and the proliferation of T cells to improve the defense ability of tissue. Polysaccharides in TCM can repair wounds in many ways at the same time. Its advantage lies in the multiple targets and multiple pathways. It is expected that the research will pay more attention to the mechanism of wound repair by polysaccharide components in TCM when improving the treatment of chronic refractory wounds.

Objective:To evaluate the residual risk (RR) of transfusion transmitted HIV (TT-HIV) after the implementation of nucleic acid amplification test (NAT) in blood screening test among blood centers in China.Methods:The data of blood donors and HIV infection markers from 2017 to 2020 were collected from 28 blood centers via the Platform of Comparison of blood establishments Practice in Chinese Mainland. The new infection rate/window period mathematical model was used for two types of blood screening strategies, namely, two rounds ELISA plus individual NAT take turn with pooling NAT (2ELISA+ ID-NAT/MP-NAT) and two ELISA plus one round pooling NAT (2ELISA+ MP-NAT), and the RR of HIV infection was estimated also based on first donors (FDs) and repeated donors (RDs) in different blood donation years. T-test analyses were conducted for comparing TT HIV RR among FDs and RDs in different blood donation years with two blood screening strategies, and the variation trend of RR in HIV test was observed.Results:From 2017 to 2020, the RR of FDs in 2ELISA+ ID-NAT/MP-NAT blood screening strategy was 2.869/10 6 person-year, 3.795/10 6 persons-year, 3.879/10 6 person-year, and 2.890/10 6 person-year respectively. The RR of RDs was 1.797/10 6 person-year, 1.502/10 6 person-year, 1.857/10 6 person-year, and 1.483/10 6 person-year respectively. Significant difference exists between RR of FDs and RDs, with F=9.898 and p<0.05. In 2ELISA+ MP-NAT strategy, the RR of FDs was 3.508/10 6 person-year, 1.868/10 6 person-year, 2.204/10 6 person-year, and 1.765/10 6 person-year respectively. The RR of RDs was 0.948/10 6 person-year, 0.926/10 6 person-year, 0.748/10 6 person-year, and 0.682/10 6 person-year respectively. Statistical difference existed between RR of FDs and RDs, with F=17.126 and P<0.05. There was no significant difference between the RR of FDs in these two strategies with F=3.493 and P>0.05, while there was a difference between the RR of RDs in these two strategies with F=24.516 and P<0.05, and a difference between the RR of total donors (TDs) in these two strategies F=20.216 and P<0.05. Conclusions:The RR of TT HIV significantly decreased after the introduction of NAT into blood test among blood centers in China. There were some differences in the RR of HIV testing among different blood screening strategies. There could be significant differences in the RR of HIV testing among different groups of blood donors. Compared with FDs, RDs is the low risk group for HIV.