OBJECTIVE: To assess the performance of a high-definition CT (HDCT) for imaging small caliber coronary stents (< or = 3 mm) by comparing different scan modes of a conventional 64-row standard-definition CT (SDCT). MATERIALS AND METHODS: A cardiac phantom with twelve stents (2.5 mm and 3.0 mm in diameter) was scanned by HDCT and SDCT. The scan modes were retrospective electrocardiography (ECG)-gated helical and prospective ECG-triggered axial with tube voltages of 120 kVp and 100 kVp, respectively. The inner stent diameters (ISD) and the in-stent attenuation value (AVin-stent) and the in-vessel extra-stent attenuation value (AVin-vessel) were measured by two observers. The artificial lumen narrowing (ALN = [ISD - ISDmeasured]/ISD) and artificial attenuation increase between in-stent and in-vessel (AAI = AVin-stent - AVin-vessel) were calculated. All data was analyzed by intraclass correlation and ANOVA-test. RESULTS: The correlation coefficient of ISD, AVin-vessel and AVin-stent between the two observers was good. The ALNs of HDCT were statistically lower than that of SDCT (30 +/- 5.7% versus 35 +/- 5.4%, p < 0.05). HDCT had statistically lower AAI values than SDCT (15.7 +/- 81.4 HU versus 71.4 +/- 90.5 HU, p < 0.05). The prospective axial dataset demonstrated smaller ALN than the retrospective helical dataset on both HDCT and SDCT (p < 0.05). Additionally, there were no differences in ALN between the 120 kVp and 100 kVp tube voltages on HDCT (p = 0.05). CONCLUSION: High-definition CT helps improve measurement accuracy for imaging coronary stents compared to SDCT. HDCT with 100 kVp and the prospective ECG-triggered axial technique, with a lower radiation dose than 120 kVp application, may be advantageous in evaluating coronary stents with smaller calibers (< or = 3 mm).
Analysis of Variance ; Cardiac-Gated Imaging Techniques/methods ; Coronary Disease/*radiography/*therapy ; Humans ; Phantoms, Imaging ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted ; *Stents ; Tomography, Spiral Computed/*methods

Objective To assess the prevalence of HIV and risky sexual behaviors among university students who have sex with men(MSM)in Beijing.Methods MSM students in the universities were mainly recruited via internet.Questionnaires were self-administered to collect social demographic information and AIDS-related risky sexual behaviors.After completing the questionnaire,blood sample was collected to determine HIV infection through serological testing.X2 test and logistic regression were employed for univariate and multivariate analysis,respectively.Results A total of 157 students were recruited with mean age of 22.7±2.8 years old,12.1%of them were minorities and 77.7% were self-identified as homosexual.98.1% had engaged in anal intercourse(AI)in their lifetime and 73.9%reported that AI was common sexual behavior they often practised.In the past 6 months,58.6% had ever had unprotected anal intercourse(UAI),58.0% never used condoms during oral intercourse,and 59.2% had multiple sex partners(≥2).Nearly half of them believed that they were at low or no risk of contracting HIV and the prevalence of HIV infection was 2.5%.Data from logistic regression analysis showed that ever having had sex with a casual partner in a lifetime (OR=13.10).understanding that serving an insertive role had less risk than being receptive during the AI (OR=3.37),and ever having been to a gay bar(OR=2.49)was independently related to having multiple sex partners in the past 6 months.Conclusion Despite the extensive programs on education,behaviors regarding UAI and ever having had multiple sex partners were silll commonly seen among university MSM students.Interventions were needed to prevent HIV transmission in this population.

OBJECTIVETo describe the characteristics and factors associated with long-term retention for methadone maintenance treatment (MMT) patients.

METHODSThis study was conducted in eight MMT clinics located in Sichuan, Yunnan, Guangxi, Guizhou and Zhejiang provinces. Five hundred and thirty-nine MMT patients who enrolled in MMT clinics in 2004 and retained in treatment by June 2010 were selected as study subjects. Chi-square tests were used to compare the demographics and drug abuse history at enrollment and treatment characteristics during the follow-up period between continuous treatment patients and discontinuous treatment patients.

RESULTSOf the 539 patients, 110 (20.4%) were continuous treatment patients whereas 429 (79.6%) were discontinuous treatment patients. Of these 429 discontinuous treatment patients, 84.1% (361/429) had 2-4 treatment episodes whereas 15.9% (68/429) had 5 or more episodes during follow-up period. When continuous treatment patients were compared with discontinuous treatment patients, living with family members or friends (88.2% (97/110), 78.5% (337/429)), age of first drug use under 25 (61.8% (68/110), 71.3% (306/429)), low urine morphine positive test results (67.3% (74/110), 38.2% (164/429)) and living within 5 kilometers of the MMT clinic (72.7% (80/110), 61.3% (263/429)) were positively associated with higher possibility of continuous treat retention (P < 0.05). Demographics and drug abuse characteristics at enrollment, including gender, age, employment status, family relationship, injection, needle sharing, criminal behavior, contacts with drug users, MMT daily dosage and family members receiving MMT were not significantly associated with treatment retention (P > 0.05).

CONCLUSIONIllicit drug use during the treatment and longer distance travelling to MMT clinic might have negative impact on patients' continuous treatment retention. Mobile MMT vehicles and expanded MMT service sites could be introduced to improve compliance of treatment retention of MMT patients.

Adult ; Female ; Humans ; Longitudinal Studies ; Male ; Methadone ; administration & dosage ; therapeutic use ; Patient Compliance ; statistics & numerical data ; Substance-Related Disorders ; drug therapy ; Treatment Outcome

OBJECTIVETo explore the family aggregation and risk factors of hepatitis B virus (HBV) transmission in Chaoyang district of Beijing.

METHODSA total of 5266 families were randomly selected for the multi-stage cluster sampling study in Chaoyang district of Beijing in 2010. The family members who aged between 1 and 70 years old and lived constantly in Beijing for over half a year, were recruited as subjects. There were 14 491 subjects in total, including temporary residents who did not have Beijing household account, except foreigners. 5 ml venous blood was drawn from every subject. A self-designed questionnaire was used to collect the basic information of the population and the risk factors of the hepatitis B transmission. Microparticle enzyme-linked immunoassay was applied to test five indicators of hepatitis B. Negative binomial distribution test was used among the HBsAg positive families to calculate the family aggregation rate of hepatitis B. Single factor analysis and multi-factor logistic regression model were used to analyze the risk factors of HBV transmission.

RESULTSIn all, 308 out of 5266 families had HBsAg positive members, accounting for 5.85%.383 out of 14 410 subjects were HBsAg positive, rating at 2.66%. The HBsAg positive rate among subjects under 14 years old was the lowest, at 0.56% (9/1603); and the positive rate among subjects aging between 35 and 44 years old was the highest, at 4.27% (47/1029). Negative binomial distribution test showed that the family aggregation rate of HBV infection was 7.66% (χ² = 15.10, P < 0.05). The analysis of family aggregation of HBsAg positive showed that 17.39% (8/46) of the transmission was from father to child, 13.04% (6/46) was from mother to child, 30.44% (14/46) was between couples, and another 39.13% (18/46) was between siblings or other relatives. Both single factor analysis and multi-factor logistic regression analysis showed that hepatitis B positive family members (OR = 5.40, 95%CI: 5.24 - 5.55), hepatitis B positive friends and colleagues (OR = 1.55, 95%CI: 1.11 - 1.99) and blood donation and transfusion history (OR = 1.96, 95%CI: 1.76 - 2.15) were the risk factors of HBV infection.

CONCLUSIONHBV transmission showed family aggregation in Beijing, however, the risk factors needed further studies.

Adolescent ; Adult ; Aged ; Carrier State ; Child ; Child, Preschool ; China ; epidemiology ; Family Characteristics ; Female ; Hepatitis B ; epidemiology ; transmission ; Hepatitis B virus ; Humans ; Infant ; Male ; Middle Aged ; Risk Factors ; Young Adult

OBJECTIVETo evaluate the effectiveness of the first eight pilot methadone maintenance treatment (MMT) clinics in China.

METHODSA questionnaire survey of the clients at the 8 pilot MMT clinics was performed at entry, 6 month and 12 month follow-up. Drug using behaviors, drug related crime behaviors, and relationships in families were compared among at entry, 6 and 12 months follow-up.

RESULTSThere were 585, 609 and 468 clients involved at baseline, 6 month and 12 month follow-up surveys, respectively. At entry, 6 month and 12 month follow-up, the proportion of clients whose injection of drugs reduced from 69.1% to 8.9% and 8.8%, and the frequency of injection in the past month had reduced from 90 times per month to 2 times per month. Employment rate increased from 22.9% to 43.2% and 40.6%, and self-reported criminal behaviors reduced from 20.7% to 3.6% and 3.8%. At 12 month follow-up, 65.8% of clients reported a healthy family relationship, increased from 46.8% at entry, 95.9% of clients reported that they were satisfied with the MMT service.

CONCLUSIONPilot MMT program reduced drug use, drug injecting behaviors, drug related criminal behaviors, and improved relationship with family members. Therefore, MMT clinic should be considered as a platform for providing comprehensive services to drug users.

Adult ; Analgesics, Opioid ; administration & dosage ; China ; Follow-Up Studies ; Humans ; Methadone ; administration & dosage ; Opioid-Related Disorders ; rehabilitation ; Outcome Assessment (Health Care) ; methods ; Program Evaluation ; methods ; Substance Abuse Treatment Centers ; organization & administration ; standards ; Surveys and Questionnaires

OBJECTIVETo explore seroepidemiological status and vaccine coverage of hepatitis B in children aging under 15 years old in Chaoyang district of Beijing.

METHODSA total of 1602 children aging under 15 years old, residents or floating population who had lived here more than six months, were randomly selected by multistage cluster sampling, from Chaoyang district of Beijing in year 2010. The demographic information and vaccine coverage of hepatitis B vaccine (HepB) were collected by self-designed questionnaire.5 ml blood was collected from each subject and the serum HBsAg, anti-HBs and anti-HBc were detected by Abbott microparticle enzyme-linked immunoassay. Those whose HBsAg was positive were then tested HBeAg and anti-HBe. The positive rate of hepatitis B indicators and coverage rate of HepB in different population were compared.

RESULTSThe positive rate of HBsAg, anti-HBs and anti-HBc were 0.56% (9/1602), 64.17% (1028/1602) and 2.12% (34/1602), respectively; while the age standardized rates were separately 0.57%, 66.36% and 1.98%; and the gender-adjusted rates were 0.56%, 64.23% and 2.12% respectively. The positive rate of anti-HBs was statistically significant (χ(2) = 165.445, P = 0.000). The positive rate of anti-HBs was up to 90.73% (235/259) among 1-2 years old children, followed by 76.22% (141/185) among 13 - 15 years old children, 67.21% (166/247) among 3 - 4 years old children, 61.22% (150/245) among 9 - 10 years old children, 60.68% (142/234) among 11 - 12 years old children, 49.05% (103/210) among 5 - 6 years old children and 40.99% (91/222) among 7 - 8 years old children. The average coverage rate of HepB was 90.44% (1371/1516), separately 93.76% (661/705) in residents and 87.55% (719/811) in floating population. The difference was statistically significant (χ(2) = 16.829, P = 0.000).

CONCLUSIONHBsAg positive rate in children under 15 years old in Chaoyang district of Beijing dropped to less than 1% and the coverage rate of HepB had reached over 90%. It is suggested that we should pay more attention to increase the coverage rate of HepB among floating children under 15 years old.

Adolescent ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Hepatitis B ; epidemiology ; prevention & control ; Hepatitis B Antibodies ; blood ; Hepatitis B Vaccines ; administration & dosage ; Humans ; Infant ; Male ; Seroepidemiologic Studies ; Vaccination ; statistics & numerical data

OBJECTIVETo explore the affecting factors on coronary heart disease among people over 40 years of age in Guangxi area, China.

METHODSBaseline data was gathered through the Third National Blood Pressure Survey in 1991 in China. A total number of 11 818 adults over 40 years old had been studied in Guangxi province. Data of morbidity and mortality of coronary heart disease was obtained.

RESULTSCardiovascular events were related to systolic blood pressure, diastolic blood pressure, pulse pressure, smoking, BMI regardless of their myocardial infarct (MI) history. Cox regression analysis showed that the relative risk for cardiovascular events increased by 21 [95% confidence interval (CI): 9.06-48.44] times for those people having MI history. When pulse pressure, systolic blood pressure, diastolic blood pressure increased by every 10 mm Hg, the relative risk for cardiovascular events increased by 1.29 (95% CI: 1.11-1.49), 1.18 (95% CI: 1.02-1.22), 1.13 (95% CI: 1.05-1.28) respectively. There was 1.23 (95% Cl: 1.05-1.45) times higher in smoker than non-smoker on relative risk for cardiovascular events. When BMI increasing 1, the relative risk for cardiovascular events would increase 1.03 (95% CI: 1.01-1 .05) times.

CONCLUSIONHypertension, smoking, increase of BMI were the risk factors of coronary heart disease among people who were over 40 years of age.

Adult ; Body Mass Index ; China ; epidemiology ; Cohort Studies ; Confidence Intervals ; Coronary Disease ; epidemiology ; etiology ; Health Surveys ; Humans ; Hypertension ; complications ; Myocardial Infarction ; Proportional Hazards Models ; Risk Factors ; Smoking ; adverse effects

OBJECTIVE To study the methodology of achieving stable co-expression of drug-metab?olizing enzymes in the HepG2 cells by the piggyBac (PB) transposon system. METHODS N-terminal attachment of enhanced green fluorscent protein plasmid (pEGFP- N2) and 2A peptide linked recombinant PB transposon plasmid containing dual-genes encoding drug metabolizing enzymes cyto?chrome P450 3A4 (CYP3A4) and CYP2C19 (pPB-CYP3A4-2A-2C19) were transfected into HepG2 cells respectively by Lipofectamine?LTX reagent, GenJetTM (Ver.Ⅱ) reagent and Neon?Transfection System reagent, which were widely used for large-sized DNA fragments transfection. 48 h later, the transfection efficiency and cell toxicity were detected and compared between the three methods so as to find a method with relatively high efficiency and low toxicity for later transfection.Then,three groups of recombinant PB transposons-single-gene transposon (PB-CYP3A4), 2A peptide linked dual-gene transposon (PB-CYP3A4-2A-2C19) and multiple single-gene transposon mixture〔PB-CYP3A4, PB-CYP2C8, PB-CYP2A6, organic anion transporting polypeptide 1B1 PB transposon (PB-OATP1B1)〕-were transfected into HepG2 cells respectively with the above established method.The puromycin (Puro)-resistant and GFP positive cell clones were picked up and further cultured. The mRNA, protein and metabolic levels of drug-metabolizing enzymes in monoclonal cell lines were detected by quantitative real-time PCR,Western blotting and high performance liquid chromatography-tandem mass spectrometry respectively after screening by Puro and green fluorescence. Comparisons of different groups were made using statistical analysis. RESULTS The comparison of three different transfection methods indi?cated that the transfection efficiency of GenJetTMwas up to(94.2±2.5)% and (89.3±3.3)%,significantly higher than those of the other two methods (P<0.01), along with lower cytotoxicity. Then GenJetTMwas chosen for later transfection. In the Puro-resistant monoclonal cell lines of single transposon PB-CYP3A4,PB-CYP3A4-2A-2C19 groups,the mRNA,protein and enzyme activity levels of drug-metabo?lizing enzymes were significantly increased respectively.The recombinant transposon (PB-CYP3A4-2A-2C19) containing 2A peptide could achieve stable and efficient co-expression of two metabolizing enzymes CYP3A4 and CYP2C19,while the expression of drug-metabolizing enzymes remained unbal?anced and random in those of multiple single-gene transposon mixture group (PB-CYP3A4, PB-CYP2C8,PB-CYP2A6,PB-OATP 1B1)(CYP3A4 was expressed in some cell clones only).CONCLUSION GenJetTM could be an effective method for the PB recombinant transposon transfection into HepG2 cells, by which the PB transposon could mediate stable expression of drug-metabolizing enzymes. In terms of multi-gene expression,a low and unbalanced expression is found by multiple transposons co-transfection method,which is different from that by virus mediated method.In contrast,mono-PB trans?poson linked by 2A peptide can achieve stable expression of multi-genes.

Objective To evaluate the long-term effectiveness of the first set 8 methadone maintenance treatment (MMT) clinics in China. Methods Repeated cross-sectional surveys were conducted on the first month after the enrollment and 5 years later,among drug users who received MMT,using a standard questionnaire.Data on demographic characteristics,HIV-related high-risk bchaviors,criminal records associatcd with drug use and related family/social functions were collected and analyzed.Results There were 252 and 195 participants being interviewed at the baseline and the 5-year surveys,respectively,.Of them,66 participants were involved in both surveys.There was no significant differences on factors as ethnicity,level of education,working status,marital status and living status (P＞0.05) between the baselinc and the 5-year surveys.Compared with data from the baseline survey,participants' behavior on drug abuse (100.0％ vs.24.1％,P＜0.001 ),needle sharing behavior ( 19.4％ vs.0.0％,P ＜ 0.001 ),and exchanging sex for drugs ( 34.5 ％ vs.0.0％,P＜0.001 ) had significant decreases at the 5-year survey.Rates on condom use ( 10.6％ vs.25.0％,P=0.004),and having jobs (27.8％ vs.47.7％,P＜0.001 ) had been improved significantly,while self-reported criminal cases related to drug use (15.1％ vs.1.5％,P＜0.001) and the contacts with drug users (88.9％ vs.31.3％,P＜0.001) had been significantly reduced after joining the MMT program.Conclusion MMT could play an active role in reducing the HIV-related high-risk behaviors,criminal cases associated with drug abuse as well as enhancing the family and social functions of the MMT patients.Providing high quality service to the MMT clinic and trying to keep the drug users stick to the program remain difficult.It was also important to improve the training programs for staff working at the MMT clinics.

OBJECTIVETo study the prevalence of hepatitis B infections and carrier status among general population in Chaoyang district, Beijing in 2010.

METHODSFrom May to December 2010, 14 491 subjects over 12 months old were selected by multistage random cluster sampling method from residents in Chaoyang district, Beijing. Five millilitre venous blood specimens were collected from these subjects to test hepatitis B virus antigens and antibodies. Status of hepatitis B infections were analyzed in different age, sex and registered permanent residence groups.

RESULTSThe overall positive rate of surface antigen (HBsAg) was 2.66% (383/14 410). The lowest rate of 0.56% (9/1603) was found in the 1 to 14 years old group and the 35 to 44 years old group had the highest rate of 4.27% (92/2154). The rate in subjects younger than 24 years old was 1.03% (31/2986). The overall positive rate of surface antibody (anti-HBs) was 40.21% (5798/14 421). The highest positive rate of anti-HBs (80.59%, 407/505) was found in the 1 to 4 years old group. The overall positive rate of core antibody (anti-HBc) was 30.26% (4364/14 424). The overall hepatitis B virus infection rate was 30.32% (4364/14 393). For male and female groups, the positive rates of HBsAg were 2.93% (179/6108) and 2.44% (202/8287) respectively (χ² = 3.32, P > 0.05); anti-HBs were 41.93% (2563/6113) and 38.96% (3231/8293) respectively (χ² = 12.88, P < 0.01); and anti-HBc were 31.39% (1919/6114) and 29.39% (2438/8295) respectively (χ² = 6.65, P = 0.01). For local residents group and mobile population group, the positive rates of HBsAg were 2.46% (283/11 510) and 3.60% (98/2719) respectively (χ² = 11.08, P < 0.01); anti-HBs were 37.11% (4293/11 568) and 53.07% (1445/2723) respectively (χ² = 233.51, P < 0.01); and anti-HBc were 30.83% (3567/11 570), and 28.41% (774/2724) respectively (χ² = 6.08, P < 0.05).

CONCLUSIONThe positive rate of HBsAg in population younger than 24 years old has reached a relatively low level. The mobile population has significantly higher positive rate of HBsAg than local residents, indicating the need for enhancing prevention and control measures for hepatitis B for the mobile population and local residents over 25 years old.

Adolescent ; Adult ; Aged ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Hepatitis B ; blood ; epidemiology ; Hepatitis B Surface Antigens ; blood ; Humans ; Infant ; Male ; Middle Aged ; Prevalence ; Seroepidemiologic Studies ; Urban Population ; Young Adult