Sero-epidemiological investigation on hepatitis B among permanent residents in Shenzhen area / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the infection status and epidemiological features of HBV in permanent residents of Shenzhen city.</p><p><b>METHODS</b>A multi-stage stratified random sampling method was performed for questionnaire survey to permanently-registered residents of 1-59 years old in Luohu and Baoan district of Shenzhen in 2010, and blood samples of the subjects were collected. Hepatitis B virus-related surface antigen (HBsAg) and hepatitis B virus surface antibody (anti-HBs) were detected with ELISA.</p><p><b>RESULTS</b>The total 3771 studied population showed 252 HBsAg positive and 2712 anti-HBs positive residents with the standardization prevalence as 9.73% and 72.83% , respectively. The difference of the prevalence of HBsAg and anti-HBs between males and females were not statistically significant (P > 0.05). The prevalence of HBsAg was reduced with increasing age. The differences of the prevalence of HBsAg between Shenzhen permanent registered and non-permanent registered population were not significant, but the prevalence of anti-HBs in Permanent registered residents (78.32%) was higher than in non-permanent (66.03%, χ(2) = 41.613, P < 0.001). The prevalence of HBsAg was significantly different in various occupational and educational levels. Peasants had the highest prevalence (24.13%) and medical workers had the highest prevalence of anti-HBs (89.10% ). People with junior high school education had the highest prevalence of HBsAg (12.76%) and the lowest of anti-HBs (62.45%). Population with high-level education had the highest prevalence of anti-HBs(81.00% average). The prevalence of HBsAg was over 10% in people who were born in Shenzhen and Guangdong province, and the anti-HBs was the highest in Shenzhen population with the prevalence as 74.48% and 76.47% , respectively.</p><p><b>CONCLUSION</b>In the Shenzhen resident population, the overall prevalence of HBV was lower than the average level of Guangdong province, but higher than the national wide.</p>

A Meta-analysis on the association between maternal passive smoking during pregnancy and small-for-gestational-age infants / 中华流行病学杂志

Objective To study the association between maternal passive smoking during pregnancy and the small-for-gestational-age (SGA) infants and to analyze independent factors on duration,in different areas.Methods Totally,8 retrospective studies published in PubMed (no year limited),OVID-MEDLINE (no year limited),CNKI (from 1911 to 2008),VIP (from 1989 to 2008),and CBM (no year limited),on maternal passive smoking during pregnancy and SGA were analyzed synthetically by Meta-analysis.Results The unadjusted pooled OR value on the association between maternal passive smoking during pregnancy and SGA was 1.45 (95%CI: 1.05-2.01).Data showed that the adjusted pooled OR value was 1.76 (95%Ch 1.15-2.69).Maternal passive smoking in early pregnancy was a risk factor for SGA(OR=1.85,95%Ch 1.25-2.72),and so was the exposure in mid or late pregnancy (OR=2.12,95%Ch 1.43-3.13).No statistically significant relationship between SGA and passive smoking at home or at workplace was found.Conclusion Avoiding passive smoking in pregnancy for mothers could reduce the possibility of delivering SGA infants.Other than at home or at workplace,problem of passive smoking in other places should also be brought up.

Potential infections of H5N1 and H9N2 avian influenza do exist in Guangdong populations of China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Southeast China is one of the sites of influenza origin. During 2003--2004, nine avian influenza outbreaks took place in Guangdong Province. But no human case was reported. To examine the status of potential human infection by human influenza (H1N1, H3N2) and avian influenza (H5N1, H7N7, H9N2) in the avian influenza epidemic area of Guangdong Province, China, we conducted a seroepidemiologic survey in the people of this area from April to June of 2004.</p><p><b>METHODS</b>Three out of 9 H5N1 avian influenza affected poultry areas in Guangdong were randomly selected, and the population living within 3 kilometers of the affected poultries were chosen as the survey subjects. One thousand two hundred and fourteen people were selected from 3 villages at random. Human and avian influenza antibody titers were determined by hemagglutination-inhibition (HI) test and microneutralization test (MNT).</p><p><b>RESULTS</b>The positive rate of antibody to H5N1 was 3.03% in the occupational exposure group and 2.34% in general citizens group; that of H9N2 was 9.52% in the occupational exposure group and 3.76% in the general citizens group. Moreover one case in the occupational exposure group was positive for H7N7. One year later, all previously positive cases had become negative except for one H5N1-positive case.</p><p><b>CONCLUSION</b>The observations imply that H5N1 and H9N2 avian influenza silent infections exist in Guangdong populations.</p>

Study on the impact of related psychological stress and fatigue to different smoking behaviors among undergraduate students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the relationship between psychological stress, fatigue and different smoking behaviors among undergraduate students.</p><p><b>METHODS</b>8138 undergraduate students in grade 1 to 3 were sampled with cluster sampling method from a comprehensive university in Guangzhou, and were studied on their psychological stress, peer and self smoking behaviors, as well as socio-demographic factors with a self-administered questionnaire. Physical and mental fatigue was measured by Chalder fatigue scale. A multinomial logistic regression analysis was performed to explore the association between psychological stress, fatigue and different smoking behaviors with 'non-smokers' defined as control group while 'triers' and 'current smokers' as case group, respectively.</p><p><b>RESULTS</b>There were students trying to smoke or becoming current smokers on university campus. After adjusting the effect of relevant socio-demographic factors and peer smoking behavior, physical fatigue (OR = 1.044, 95% CI: 1.013-1.075) and 'worry about current academic and future work' (OR = 1.020, 95% CI: 1.001-1.040) were the risk factors of trying to smoke among male students, while 'study stress (OR = 1.063,95% CI: 1.012-1.117) was the risk factor for female students when start smoking. 'Personnel relationship and environment stress' (OR = 1.152, 95% CI: 1.012-1.312) were the risk factors for female students' current smoking behavior.</p><p><b>CONCLUSION</b>Psychological stress and fatigue were moderately associated with smoking behavior among undergraduate students and the impact was different on different gender and smoking behaviors that suggesting that some specific psychological measures should be taken so as to control different smoking behaviors among undergraduate students.</p>

The effect of anthocyanins on cholesterol efflux from mouse peritoneal macrophage-derived foam cells and its possible molecular mechanism / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the potential role of anthocyanins on modulating cholesterol efflux in mouse peritoneal macrophage-derived foam cells and related molecular mechanisms.</p><p><b>METHODS</b>The macrophages were isolated from pathogen-free NIH mice and were loaded with 50 microg/ml oxLDL for 24 hours, newly formed foam cells were then treated with anthocyanins (cyanidin-3-glucoside, Cy-3-g; or peonidin-3-glucoside, Pn-3-g) at the concentrations of 1 micromol/L, 10 micromol/L, 100 micromol/L for 0 to 36 hours, respectively. The enzymatic-fluorescent method was used to determine cholesterol content in culture medium. ABCA1 expressions at mRNA and protein level were detected by real-time PCR and confocal microscope.</p><p><b>RESULTS</b>Cholesterol efflux of macrophage-derived foam cells increased in a time- and dose-dependent manner post anthocyanins treatment. ABCA1 expressions at mRNA and protein levels were also significantly enhanced after anthocyanins treatment in these cells and these effects could be blocked by co-treatment with DIDS, an inhibitor of the transport activities of ABCA1 and blocker of apoAI-mediated cholesterol efflux.</p><p><b>CONCLUSION</b>These data demonstrate that anthocyanins induce cholesterol efflux from mouse peritoneal macrophage-derived foam cells via regulating ABCA1 expression.</p>

Possibility and predictors of successful cigarette purchase attempts by 201 primary school students in Guangzhou, China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the access to tobacco and exam the predictors of successful tobacco purchase attempts among Chinese minors.</p><p><b>METHODS</b>A simulative trial of purchasing cigarettes was participated by 201 sixth grade students to assess the prevalence of illegal cigarette sales to minors in Guangzhou. Methods of Chi-square and unconditional logistic regression were used to identify the significant predictors,with the result of tobacco purchase as the dependent variable and the characteristics of stores, retailers and minors as the independent variables.</p><p><b>RESULTS</b>A total of 165 students succeeded in purchasing cigarettes but 36 failed, and the percentage of successful purchase attempts was 82. 1% . Data from univariate analysis indicated that 9 factors were significantly associated with students' success in purchasing cigarettes. They were age and height of the purchasers, types of stores, seller's gender and age, posting cigarette advertisements,showing warning signs of 'no cigarette selling to minors' ,asking buyer's age,and asking whom you buy the cigarettes for. The results of multivariable analysis showed that only three variables entering the final logistic regression: the age of students, the type of stores, and showing warning signs of 'no cigarette selling to minors'.</p><p><b>CONCLUSION</b>Chinese minors have easy access to purchasing cigarettes, especially in groceries and small markets. Selling cigarettes by sellers to minors should be monitored and managed in the future.</p>

Process evaluation on a health promotion model regarding smoking prevention among Chinese secondary school students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the process of smoking prevention and control among Chinese adolescent with a model on health promotion in junior high school.</p><p><b>METHODS</b>A cluster-randomized, controlled and schooled-based trial on smoking prevention was conducted among 2343 students at four secondary schools in Huangpu District of Guangzhou. Students 'reports and investigators' daily records were used to evaluate the intervention measures.</p><p><b>RESULTS</b>During the one-year period of intervention (Dec. 2004 through Dec. 2005), eighteen activities had been implemented among students, teachers, parents and cigarette retailers. Ranked by the rate of awareness, the top six activities were shown as follows: "the nicotine toxicity experiment" (90.7%), "agreement of building families free of smoking"(77.7%), "a letter to parents" (77.1%), "no-smoking signs" (76.5%), "Blackboard information about health and smoking" (75.0%), and "signature on the 18th World Day of No Smoking" (70.2%). Among all the activities, "the nicotine toxicity experiment" had the highest rate of participation (88.5%), followed by "a letter to parents" (73.6%), "agreement of building families free of smoking" (69.8%), "health education through experiments"(68.6%), "health education through multimedia" (65.7%) and "signature on the 18th World Day of No Smoking" (65.6%). The top seven activities in which students showed greatest interests were "the nicotine toxicity experiment" (64.5%), "signature on the 18th World Day of No Smoking" (33.0%), "health education through experiments" (31.2%), "health education through multimedia" (29.8%), "class meetings with a thesis of smoking" (26.8%), "health pamphlets" (26.6%), "specific textbooks" (25.9%). The extent of students' general satisfaction to the work of tobacco control in school during the last year was 52.4%. The biggest perceived shortcoming for the intervention plan was the low participation of students.</p><p><b>CONCLUSION</b>Some intervention measures had not been fully carried out among the students and only covered part of them. It is necessary to adjust the previous intervention measures through keeping the nicotine toxicity experiment, health education through multimedia and other measures with extensive participation of students and at the same time, to avoid literal materials, exhibition boards and traditional single-way health education program.</p>

Study on the determinants of 'signing agreements' to establish smoke-free homes among 2019 parents of the secondary school students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the determinants of 'signing a agreement for establishing smoke-free homes' among the parents of secondary school students.</p><p><b>METHODS</b>2019 parents were surveyed with self-administered questionnaires on their socio-demographic characteristics, smoking behaviors, attitude toward tobacco control at home and related data of their children. At the same time, parents were asked to sign an agreement for making the 'home as smoking-free'. 'Parents signing the agreement' was defined as dependent variable (0=no, 1=yes), and parent's age, gender, educational level, etc. were defined as independent ones. Multi-variant logistic regression analysis was conducted for identifying the determinants of the parents to sign an agreement for establishing 'smoking-free homes'.</p><p><b>RESULTS</b>Of the 2019 surveyed parents, 1047 (51.86%) had signed the agreement including 49.25% of the fathers and 55.73% of the mothers. The results from multi-variant logistic regression analysis indicated that father's 'signing action' was significantly associated with (a) their intention of carrying out the agreements (OR = 3.37), (b) to teach their children about the consequence between smoking and health (OR = 2.10), (c) knowing tobacco control program at school (OR = 1.38), (d) reading tobacco control material provided by school (OR = 1.38), (e) being current smoker (OR = 0.53) compare to that the mother's 'signing action' was significantly associated to (a) intention to carrying out agreements (OR = 2.36), (b) teaching children not to smoke (OR = 2.22), (c) reading tobacco control material provided by school (OR = 1.57).</p><p><b>CONCLUSION</b>Changing parental cognition and attitude toward smoking was beneficial to promote parental participation in tobacco control campaign and to establish 'smoking-free homes'.</p>

Analysis on factors influencing the smoking behaviors among male secondary school students under the structural equation model / 中华流行病学杂志

<p><b>OBJECTIVE</b>To analyze the direct and indirect outcomes of influencing factors on smoking behaviors among adolescents.</p><p><b>METHODS</b>Self-administered questionnaires were used to collect smoking-related information from 2021 respondents. Measurement models were built by confirmatory factor analysis and parameters were estimated by ERLS method. The final structural equation model was determined by comprehensive evaluation and necessary modification.</p><p><b>RESULTS</b>Three latent variables were extracted from 10 manifest variables of environment, while only one latent variable was identified from 9 manifest variables of attitudes. The goodness of fit for the structural equation model was satisfactory that all indices had met corresponding requirements. The final model could explain 38.8% of the variance of smoking behaviors. Four factors (smoking environment, smoking restriction from parents and teachers, determination of cigarette refusal and attitudes toward smoking) were directly affecting the smoking behaviors, while another three factors (grade, health knowledge and school environment) had indirect impacts. According to the percentages of their contribution, the risk factors were ranked as follows: smoking environment (45.76%), attitudes toward smoking (19.88%) and grade at school (0.44%). Similarly, the top protective factor were: determination of cigarette refusal (16.61%), followed by smoking restriction from parents and teachers (10.51%), health knowledge (3.89%) and school environment (2.92%).</p><p><b>CONCLUSIONS</b>Heath knowledge had minor effect on smoking in adolescents but could indirectly affect their smoking behaviors through changing their belief. Grade at school had a doubled influence on smoking, but mainly served as a risk factor. Tobacco control measures for adolescents should not only be limited to health education but environment factors as well.</p>

Relationship between paraoxonase 1 55 Met/Leu, paraoxonase 2 148 Ala/Gly genetic polymorphisms and coronary artery disease / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the relationships between paraoxonase 1 55 Met/Leu (PON1 55Met/Leu), paraoxonase 2 148 Ala/Gly(PON2 148Ala/Gly) genetic polymorphisms and coronary artery disease(CAD), plasma activities of paraoxonase (PON), total superoxide dismutase (T-SOD), as well as plasma concentration of maleic dialdehyde (MDA).</p><p><b>METHODS</b>The PCR-RFLP method was applied to identify the genetic polymorphisms of PON1 55Met/Leu and PON2 148Ala/Gly, and the colorimetry way was used to detect plasma activities of PON, T-SOD and plasma MDA concentration of 262 CAD patients and 100 controls.</p><p><b>RESULTS</b>Comparing with control, the CAD patient had the obviously lower activities of enzymes PON (349.27+/- 138.36 nmol/min.mL vs 454.75+/- 166.00 nmol/min.mL, P< 0.001) and T-SOD (23.61+/- 16.51 U/mL vs 44.01+/- 22.68 U/mL, P< 0.001) while getting the plasma MDA concentration increased markedly(2.47+/- 0.73 nmol/mL vs2.15+/- 0.55 nmol/mL, P< 0.01). The CAD patient had more LM genotype and M allele of PON1 55Met/Leu(24.8% vs 1.4%, P< 0.001 and 12.4% vs 0.5%, P was 0.001 respectively), GG and AG genotype and G allele of PON2 148 Ala/Gly(11.8% vs 5.0%, P< 0.001; 48.1% vs 24.0%, P< 0.001 and 36.0% vs 17.0%, P< 0.001 respectively) than control did. The activities of plasma PON and T-SOD were lower in individuals with PON??1 55 LM genotype than those with LL genotype(304.73+/- 125.04 vs 394.84+/- 154.87 nmol/min.mL and 24.89+/- 16.14 vs 30.22+/- 21.29 U/mL, P< 0.001 and P< 0.05 respectively). The activity of plasma PON was also lower in individuals with PON2 148 GG/AG genotype than that with AA genotype(281.47+/- 84.70 vs 356.00+/- 145.95 vs 417.34+/- 159.00 nmol/min.mL, P< 0.001). Logistic regression analysis showed that PON1 55 LM genotype (OR 29.08, 95%CI 2.88-294.04, P was 0.004) and M allele(OR 15.17, 95%CI 1.32-174.29, P was 0.029), PON2 148 GG/AG genotype (OR 2.32, 95%CI 1.52-3.54, P< 0. 001) and G allele (OR 3.24, 95%CI 1.38-7.61, P was 0.007) were independent risk factors for CAD.</p><p><b>CONCLUSION</b>The CAD patient has the obviously low activities of plasma PON and T-SOD but on the contrary, get the plasma MDA concentration increased markedly. PON1 55 LM genotype and M allele, PON2 148 GG/AG genotype and G allele are the risk factors for coronary artery disease, and the activity of plasma PON is also markedly reduced in individuals with above genotypes.</p>

Study of the association between paraoxonase1 55 Met/Leu, paraoxonase2 148 Ala/Gly and manganese superoxide dismutase (MnSOD) 9 Ala/Val genetic polymorphisms and coronary heart disease / 中华流行病学杂志

<p><b>OBJECTIVE</b>To study the associations between paraoxonase, 55 Met/Leu (PON1 55 Met/ Leu), paraoxonase2 148 Ala/Gly (PON2 148 Ala/Gly) and manganese superoxide dismutase 9 Ala/Val (MnSOD 9 Ala/Val) genetic polymorphisms and coronary heart disease (CHD), plasma activities of paraoxonase (PON), total superoxide dismutase (T-SOD), MnSOD, as well as plasma concentration of maleic dialdehyde (MDA).</p><p><b>METHODS</b>Using PCR-RFLP method to identify genotype of PON1 55 Met/Leu, PON2 148 Ala/Gly and MnSOD 9 Ala/Val genetic polymorphisms, and using colorimetry to detect plasma activities of PON, T-SOD, MnSOD and plasma concentration of MDA in 262 CHD patients and 100 controls.</p><p><b>RESULTS</b>Compared with controls, the plasma activities of PON [(349.27 +/- 138.36 vs. 454.75 +/- 166.00) nmol x min(-1) x ml(-1), P < 0.001], T-SOD [(23.61 +/- 16.51 vs. 44.01 +/- 22.68) U/ml, P < 0.001] and MnSOD [(21.56 +/- 13.11 vs. 28.79 +/- 8.65) U/ml, P < 0.001] reduced obviously,while plasma MDA concentration increased markedly [(2.47 +/- 0.73 vs. 2.15 +/- 0.55)nmol/ml, P < 0.01] in CHD patients. There were more LM genotype and Met allele of PON, 55 Met/Leu (24.8% vs. 1.4%, P < 0.001 and 12.4% vs. 0.5%, P = 0.001, respectively), GG and AG genotype and G allele of PON2 148 Ala/Gly (11.8% vs. 5.0%, P < 0.001, 48.1% vs. 24.0%, P < 0.001 and 36.0% vs. 17.0%, P < 0.001, respectively) and AA genotype, A allele of MnSOD 9 Ala/Val genetic polymorphisms (64.2% vs. 43.0%, P = 0.001 and 80.0% vs. 67.0%, P = 0.014, respectively) in CHD patients than in controls. The activities of plasma PON and T-SOD were lower in individuals with PON1 55 LM genotype than those with LL genotype. The activity of plasma PON was also lower in individuals with PON2 148 GG/AG genotype than those with AA genotype. The activities of plasma PON and MnSOD depressed in individuals with MnSOD AA genotype compared with those with VV genotype. Logistic regression analysis demonstrated that PON1 55 LM genotype, PON2 148 GG/AG genotype and G allele were independent risk factors for CHD.</p><p><b>CONCLUSION</b>The antioxidative ability decreased, while lipid superoxide increased in CHD patients. Gene polymorphisms of PON1 55 Met/Leu, PON2 148 Ala/Gly and MnSOD 9 Ala/Val seemed to involve in the morbidity of CHD by influencing the plasma activities of PON and MnSOD.</p>

Variation analysis of the severe acute respiratory syndrome coronavirus putative non-structural protein 2 gene and construction of three-dimensional model / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The rapid transmission and high mortality rate made severe acute respiratory syndrome (SARS) a global threat for which no efficacious therapy is available now. Without sufficient knowledge about the SARS coronavirus (SARS-CoV), it is impossible to define the candidate for the anti-SARS targets. The putative non-structural protein 2 (nsp2) (3CL(pro), following the nomenclature by Gao et al, also known as nsp5 in Snidjer et al) of SARS-CoV plays an important role in viral transcription and replication, and is an attractive target for anti-SARS drug development, so we carried on this study to have an insight into putative polymerase nsp2 of SARS-CoV Guangdong (GD) strain.</p><p><b>METHODS</b>The SARS-CoV strain was isolated from a SARS patient in Guangdong, China, and cultured in Vero E6 cells. The nsp2 gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into eukaryotic expression vector pCI-neo (pCI-neo/nsp2). Then the recombinant eukaryotic expression vector pCI-neo/nsp2 was transfected into COS-7 cells using lipofectin reagent to express the nsp2 protein. The expressive protein of SARS-CoV nsp2 was analyzed by 7% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The nucleotide sequence and protein sequence of GD nsp2 were compared with that of other SARS-CoV strains by nucleotide-nucleotide basic local alignment search tool (BLASTN) and protein-protein basic local alignment search tool (BLASTP) to investigate its variance trend during the transmission. The secondary structure of GD strain and that of other strains were predicted by Garnier-Osguthorpe-Robson (GOR) Secondary Structure Prediction. Three-dimensional-PSSM Protein Fold Recognition (Threading) Server was employed to construct the three-dimensional model of the nsp2 protein.</p><p><b>RESULTS</b>The putative polymerase nsp2 gene of GD strain was amplified by RT-PCR. The eukaryotic expression vector (pCI-neo/nsp2) was constructed and expressed the protein in COS-7 cells successfully. The result of sequencing and sequence comparison with other SARS-CoV strains showed that nsp2 gene was relatively conservative during the transmission and total five base sites mutated in about 100 strains investigated, three of which in the early and middle phases caused synonymous mutation, and another two base sites variation in the late phase resulted in the amino acid substitutions and secondary structure changes. The three-dimensional structure of the nsp2 protein was successfully constructed.</p><p><b>CONCLUSIONS</b>The results suggest that polymerase nsp2 is relatively stable during the phase of epidemic. The amino acid and secondary structure change may be important for viral infection. The fact that majority of single nucleotide variations (SNVs) are predicted to cause synonymous, as well as the result of low mutation rate of nsp2 gene in the epidemic variations, indicates that the nsp2 is conservative and could be a target for anti-SARS drugs. The three-dimensional structure result indicates that the nsp2 protein of GD strain is high homologous with 3CL(pro) of SARS-CoV urbani strain, 3CL(pro) of transmissible gastroenteritis virus and 3CL(pro) of human coronavirus 229E strain, which further suggests that nsp2 protein of GD strain possesses the activity of 3CL(pro).</p>

Study on the related factors of smoking behavior transition at different stages among undergraduate students / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the influencing factors of smoking behavior transition at different stage of smoking among undergraduate students.</p><p><b>METHODS</b>8138 undergraduate students from grade 1 to 3 were selected using cluster sampling method from an university in Guangzhou with their smoking behaviors and relevant factors studied through a self-administered questionnaire. Beginners, un-regular smokers and regular smokers were defined as "case group", while non-smokers, beginners and un-regular smokers were defined as "control group" accordingly. Three multivariable logistic regressions were separately conducted to explore the influencing factors of behavioral transition at different stage of smoking.</p><p><b>RESULTS</b>Of the 8138 students investigated, the prevalence rates of beginners, un-regular smokers and regular smokers were 19.6%, 2.0% and 1.1%, respectively; while all of the above said three rates increased with grades of the students. Some students might still try to smoke or become regular smoker in the university. In male undergraduate students, determinants for the transition from non-smokers to s mokers were: source of students, father' s educational level, smoking-related knowledge and belief, and smoking habit of the roommates. Risks that influencing the transition from beginners to un-regular smokers were: being non-medical students,smoking-related belief, roommates and classmates who were smokers and transition from un-regular smokers to regular smokers would include father' s educational level and average income of family. In female undergraduate students,influencing factors from non-smokers to beginners were mother's educational level, smoking-related belief, and roommates smokers, while father's educational level, roommates and classmates' smoking habits were significant associated with beginners' change to un-regular smokers.</p><p><b>CONCLUSION</b>The influencing factors related to the transition of different stage on smoking would be different in undergraduate students,and some specific measures should be taken based on the different stage of smoking.</p>

Effects of LOX-1 on expression of adhesion molecules induced by ox-LDL in HUVECs / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the effects of oxidized low-density lipoprotein receptor 1 (LOX-1) on secretion of adhesive molecules mediated by ox-LDL in human umbilical endothelial cells (HUVECs).</p><p><b>METHODS</b>HUVECs with different concentration of ox-LDL (0, 10, 20, 50, 100 microg/ml) were incubated for 24 h, or HUVECs were pretreated with 250 microg/ml poly (I) or 250 microg/ml carrageenan for 2 h and then incubated with 50 microg/ml ox-LDL for another 24 h. Expression of LOX-1 was determined by realtime RT-PCR and Western blot. mRNA and protein of ICAM-1, VCAM-1 and E-selectin were examined by RT-PCR and Western blot respectively.</p><p><b>RESULTS</b>Incubation of HUVECs with ox-LDL (10-100 microg/ml) enhanced the expressions of LOX-1, ICAM-1 and E-selectin in a concentration-dependent manner (P < 0.01). On the contrary, ox-LDL did not affect the expression of VCAM-1 by HUVECs. The expression of LOX-1, ICAM-1 and E-selectin induced by ox-LDL were reduced in HUVECs pretreated with 250 microg/ml poly (I) or 250 microg/ml carrageenan for 2 h and then incubated with 50 microg/ml ox-LDL for 24 h. This showed that both poly (I) and carrageenan obviously decreased the expression of LOX-1, ICAM-1 and E-selectin induced by ox-LDL.</p><p><b>CONCLUSION</b>ox-LDL may upregulate the expression of LOX-1, ICAM-1 and E-selectin, and LOX-1 blocker may partly inhibit this upregulation. The results suggest that the expression of inflammatory molecules induced by ox-LDL in HUVECs is mediated by LOX-1.</p>

Humoral immune responses in rabbits induced by an experimental inactivated severe acute respiratory syndrome coronavirus vaccine prepared from F69 strain / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The etiologic agent of severe acute respiratory syndrome (SARS) has been confirmed to be a novel coronavirus (CoV), namely SARS-CoV. Developing safe and effective SARS-CoV vaccines is essential for us to prevent the possible reemergence of its epidemic. Previous experiences indicate that inactivated vaccine is conventional and more hopeful to be successfully developed. Immunogenicity evaluation of an experimental inactivated SARS-CoV vaccine in rabbits was conducted and reported in this paper.</p><p><b>METHODS</b>The large-scale cultured SARS-CoV F69 strain was inactivated with 0.4% formaldehyde and purified, then used as the immunogen combined with Freund's adjuvant. Eight adult New Zealand rabbits were immunized four times with this experimental inactivated vaccine. Twelve sets of rabbit serum were sampled from the third day to the seventy-fourth day after the first vaccination. The titers of specific anti-SARS-CoV IgG antibody were determined by indirect enzyme-linked immunosorbent assay, and the neutralizing antibody titers were detected with micro-cytopathic effect neutralization test.</p><p><b>RESULTS</b>Rapid and potent humoral immune responses were induced by the inactivated SARS-CoV vaccine in all the eight test rabbits. Titers of both specific IgG antibody and neutralizing antibody peaked at about six weeks after first vaccination, with the maximum value of 1:81 920 and 1:20 480, respectively. After that, serum antibody levels remained at a plateau or had a slight decrease, though two boosters were given in the succedent 4 to 5 weeks. Cross neutralization response existed between SARS-CoV F69 strain and Z2-Y3 strain.</p><p><b>CONCLUSIONS</b>The inactivated SARS-CoV vaccine made from F69 strain owns strong immunogenicity, and the cross neutralization response between the two different SARS-CoV strains gives a hint of the similar neutralizing epitopes, which provide stable bases for the development of inactivated SARS-CoV vaccines.</p>