Comparative Evaluation of Standard RT-PCR Assays and Commercial Real-Time RT-PCR Kits for Detection of Lassa Virus.

Lassa virus (LASV) is a causative agent of hemorrhagic fever epidemic in West Africa. In recent years, it has been transmitted several times to North America, Europe, and Asia. Standard reverse transcription (RT)-PCR and real-time RT-PCR are extensively used for early detection of LASV. However, the high nucleotide diversity of LASV strains complicates the development of appropriate diagnostic assays. Here, we analyzed LASV diversity clustered with geographic location and evaluated the specificity and sensitivity of two standard RT-PCR methods (GPC RT-PCR/1994 and 2007) and four commercial real-time RT-PCR kits (namely, Da an, Mabsky, Bioperfectus, and ZJ) to detect six representative LASV lineages using in vitro synthesized RNA templates. The results showed that the GPC RT-PCR/2007 assay had better sensitivity compared to the GPC RT-PCR/1994 assay. The Mabsky and ZJ kits were able to detect all RNA templates of six LASV lineages. Contrastingly, the Bioperfectus and Da an kits failed to detect lineages IV and V/VI. The limit of detection for lineage I with the Da an, Bioperfectus, and ZJ kits were significantly higher than that of the Mabsky kit at an RNA concentration of 1 × 1010 to 1 × 1011 copies/mL. The Bioperfectus and Da an kits detected lineages II and III at an RNA concentration of 1 × 109 copies/mL, higher than that of the other kits. In conclusion, the GPC RT-PCR/2007 assay and the Mabsky kit were suitable assays for the detection of LASV strains based on good analytical sensitivity and specificity. IMPORTANCE Lassa virus (LASV) is a significant human pathogen causing hemorrhagic fever in West Africa. Increased traveling around the world raises the risk of imported cases to other countries. The high nucleotide diversity of LASV strains clustered with geographic location complicates the development of appropriate diagnostic assays. In this study, we showed that the GPC reverse transcription (RT)-PCR/2007 assay and the Mabsky kit are suitable for detecting most LASV strains. Future assays for molecular detection of LASV should be based on specific countries/regions along with new variants.

Neurotoxic effect of the complex of the ovine prion protein (OvPrP(C)) and RNA on the cultured rat cortical neurons.

Prion diseases are conformational diseases, many factors are involved in altering the conformation of prion, such as RNA, DNA, pH, and copper etc. However the neurotoxic mechanism of prion diseases is not clear yet. The aim of this study is to investigate the effect of the nucleoprotein complex of RNA and recombinant ovine prion protein (OvPrP(C)) on the cultured rat cortical neurons in vitro. Our previous study revealed that the nucleoprotein complex (OvPrP(C)-RNA) is characterized with high ß sheet conformation and proteinase K resistance. Here we found that the OvPrP(C)-RNA induced marked neuronal cell death by the MTT (3-(4,5-dimethyl-thiazole -2-yl)-2,5-diphenyl -tetrazolium bromide) and TUNEL (TdT mediated biotin-dUTP nicked-end labeling) assay, and the neurotoxic effects were confirmed by testing the content of Bcl-2 Associated X protein (Bax) in the immunoprecipitation assay and Western blot assay. Compared to the control group, there is no significant difference of active Bax or total Bax after RNA alone treatment or OvPrP(C) alone treatment, but the OvPrP(C)-RNA induced significant increases of active Bax level, while the contents of total Bax had no obvious changes after OvPrP(C)-RNA treatment. The results suggested that OvPrP(C)-RNA is neurotoxic in vitro, which added further evidence to the current understanding of mechanism of cellular injury by RNA molecules for transformation of the PrP(C) to PrP(Sc).

[Factors associated with attitudes toward tobacco control policy in public places among adults in three counties of China].

OBJECTIVE: vestigate the attitudes of urban and rural community members toward total banning on smoking in public places and to explore the factors associated with these attitudes, in three counties/cities in China. METHODS: A cross-sectional study was conducted in three counties/cities in 2004, including Xin' an county of Henan province, Anyi county of Jiangxi province, and Mianzhu city of Sichuan province. A total of 5642 residents at age of 18-69 years old were interviewed face-to-face with a uniform questionnaire by locally-trained interviewers, through a random three-stage stratified sampling in each county. Factors were assumed to be associated with attitudes, using chi-square test in univariate analysis and non-conditional logistic regression model in multivariate analysis. RESULTS: The prevalence of current smoking among respondents was 44.3%. 80.7% (1379/1709) of the current smokers reported smoking often or sometimes in public places. Only 9.6% (479/4983) of the respondents reported that their indoor workplaces had totally banned on smoking. 43.5% of the respondents supported a total smoking ban strategy in pubic venues. The results of multivariate logistic regression model showed that eight factors were significantly associated with support for the total smoking ban in public places included region, residency, age, gender, education, smoking status, awareness about passive smoking hazards, and hearing of any message on tobacco control through media differences of rates regarding the factors as: residents in urban to rural areas (OR = 1.29), elderly to youngsters (30-49 vs. 18-29, OR = 1.46; 50-69 vs. 18-29, OR = 1.71), female to male (OR = 1.27), high-educated to less-educated ones, quitters to current smokers (OR = 1.90), nonsmokers to current smokers (OR = 2.01). Those who know messages on health hazards of passive smoking (OR = 2.26), or heard of message on tobacco control through media (OR = 1.43). CONCLUSION: Results from our study revealed that a thorough smoke-free policy in public places should be developed and implemented in these three counties/cities.

[The current status of passive smoking in Chinese families and associated factors].

OBJECTIVE: To understand the prevalence of passive smoking in Chinese families and discuss its associated factors, as to providing scientific evidence for establishing tobacco control measures in China. METHOD: Cross-sectional survey: from June to September, 2004, we randomly selected six counties in three different provinces ( Mianzhu and Xichong of Sichuan Province; Anyi and Hukou of Jiangxi Province; Xinan and Yanshi of Henan Province) and performed face-to-face questionnaire survey on citizens between 18 and 69 years old. All the data were double independently input by professional data entry company to ensure data accuracy. The prevalence of home passive smoking exposure in families with different demographic characteristics was described by using prevalence, and the possible correlated factors of home passive smoking exposure as independent variables, multiple factors were analyzed using Logistic Stepwise Regression Analysis method. RESULTS: The analysis on 8142 nonsmokers revealed that the rate of passive smoking was 28.42%, with 27.38% of male and 28.93% of female suffering from passive smoking. All 87.19% of the smokers would smoke in front of their families. As many as 42.14% of the nonsmokers would offer cigarettes to their guests, while about 46.82% of the nonsmokers would suggest smokers to smoke outdoor. Home restriction on tobacco was extremely rare and only 6.33% of all the families completely forbade smoking. Multivariate logistic regression analysis of non-conditions revealed that, there was a lower level of involuntary tobacco smoke exposure in female, older age group, lower education level, divorced, or widowed families. There was no difference in involuntary tobacco smoke exposure between town dwellers and county dwellers, but such difference did exist in different districts. CONCLUSION: The three provinces under investigation should have severe involuntary tobacco smoking exposure. Gender, age, literacy level, occupation and region should be all factors that influence the status of involuntary tobacco smoking exposure in different families. There is a high percentile that smokers would smoke in front of their families and kids and a relative low pressure against smoking from nonsmokers. Cigarette offering is very prevalence. The knowledge and attitude about passive smoking should be separated from the situation of passive smoking exposure.

Exploring barriers to implementation of smoking policies: a qualitative study on health professionals from three county-level hospitals.

OBJECTIVE: This study was to identify factors limiting the implementation of smoking policies in county-level hospitals. METHODS: We conducted qualitative interviews (17 focus groups discussions and 6 one-to-one in depth interviews) involving 103 health professionals from three target county-level hospitals. A combination of purposive and convenience sampling was used to recruit subjects and gain a broad range of perspectives on issues emerging from ongoing data-analysis until data saturation occurred. The transcripts were analyzed for themes and key points. RESULTS: The main themes that emerged suggested that both smokers and non-smokers viewed smoking very negatively. However, it was clear that, underlying this acceptance of the health risks of smoking, there was a wide range of beliefs. Most of the health professionals pointed out that, as smoking was legal, addictive, and influenced by social norms, currently it was almost unrealistic to expect all smokers to give up smoking or not to smoke in the hospitals. Furthermore, they were concerned about the potentially detrimental effects of providing counseling advice to all smokers on the interpersonal relationship among colleagues or between doctors and patients. In addition, low level of employee participation influenced the sustainable implementation of smoking policies. CONCLUSIONS: Simply being aware of the health risks about smoking did not necessarily result in successful implementation of the smoking policies. Application of comprehensive intervention strategies such as implementing smoking policies in public places at the county level, creating supportive environments, promoting community participation, and conducting health education, may be more effective.

Passive smoking in China: contributing factors and areas for future interventions.

OBJECTIVE: To reduce tobacco consumption and exposure to passive smoking in China. METHODS: Discussion consisting of 80 focus groups and 35 interviews were held in three rural intervention counties of Jiangxi, Henan, and Sichuan Provinces. Participants came from hospitals, schools, rural areas, and urban areas. RESULTS: Tobacco use and exposure to passive smoking were widely prevalent in the investigated schools, hospitals, county towns, and rural areas. Knowledge of the risks for passive smoking on health is lacking, especially in rural areas. Barriers to the control of tobacco use in public places include reluctance of administrators to implement tobacco control policies, lack of consistent policies, difficulties with regulations and enforcement, and reluctance of non-smokers to exercise their right to clean air. CONCLUSION: To curb the current tobacco epidemic in China, tobacco control efforts must focus on reducing exposure to passive smoking. A strategy should be formulated to reduce the factors that contribute to tobacco use and exposure to passive smoking.