Objective To investigate the trend and related determinants of cigarette smoking on experimental smokers among undergraduate students in Changsha.Methods Stratified sampling method was adopted and 3600 undergraduate students from grade 1 to 3 in Changsha city were investigated through a self-administered questionnaire.All the experimental smokers during the last month were selected and divided into two groups based on the present smoking status.x2 test and logistic regression analysis were used to compare the differences of cigarette smoking among subpopulations and to explore the determinants.Results Among the 1550 experimental smokers of undergraduate students,the prevalence of cigarette smoking was 30.8％(95％CI:28.5-33.1).Students from the second-class(OR=2.367)or the third-class universities(OR=2.562)were more likely to adopt smoking behavior than those from top universities.Students majored in sports or arts(OR=2.456)were significantly more inclined to smoke than the liberal arts students.Students whose father were cadres(OR=1.602)were more likely to become smokers than those whose fathers were workers.Students being males(OR=7.386),having high monthly expenses(OR=1.139),with positive attitude to smoking benefits(OR=1.140)were risk factors for smoking.Number of smoking members in the family(OR=1.801)was significantly associated with the prevalence of cigarette smoking.Knowledge on diseases caused by smoking(OR=0.806)was protecting factor to smoking among the experimental smokers.Conclusion Those experimental smokers among undergraduate students might become smokers and the determinants of cigarette smoking behavior would include:ranking of universities,students' major,gender,father' s occupation,amount of pocket money,number of smoking members in the family,knowledge about smoking,the attitude to the benefit of smoking.

Objective To study the features,safe Sex behavior and the size of men who have sex with men(MSM)population in actuaI and virtual venues in one city.Methods We carried out a cross-sectional study in actual and virtual venues,using the Estimated Size of Population from a Single Sample(LMS method)to estimate the size of MSM population.Results Most MSM in actual venues were 24-43 year olds and had received high school education,whereas in virtual venues,the majority of this population were younger than 29 years old and had higher education,including some college students.The awareness of AIDS of the two groups from different venues showed no statistically significant difierence,neither the safe sex behaviors.Proportions of the MSM population in actual and virtuaI venues were 21.22%(16 383,95%CI:11514-21252)and 78.78%(60830,95%CI:57327-64329),respectively.After adjusting the overlapping part of the MSM from both venues,the total number was between 60 830 and 77213,constituting a proportion of 5.03%-6.38%in the sexually active male population(15-64 year olds)in this city.Conclusion The size of the MSM population was large but the characteristics were different in the actual or virtual venues.As most MSM preferred going to the virtual venues,intervention program on AIDS-specific strategy in this area,in particular dealing with the Internet,should be strenthened.

AIMTo investigate the influence of particle size and methoxypolyethyleneglycol (MePEG) molecular weight on the in vitro macrophage uptake and in vivo long circulating of recombinant human tumor necrosis factor-alpha (rHuTNF-alpha)-loaded stealth nanoparticles in rats.

METHODSThree sizes (approximately 80, 70 and 240 nm) of poly (methoxypolyethyleneglycol cyanoacrylate-co-n-hexadecyl cyanoacrylate) (PEG-PHDCA) nanoparticles loading rHuTNF-alpha were prepared at different MePEG molecular weights (Mr 2,000, 5,000, 10,000) using the double emulsion method. The in vitro macrophage uptake and in vivo long circulating properties in rats were examined and compared.

RESULTSThe uptake by macrophages decreased and the half-life of rHuTNF-alpha in rat increased with the increase of MePEG molecular weight or the decrease of particle size. The linear-ships between particle size and MePEG molecular weight and the in vitro macrophage uptake and in vivo long circulating properties were fairly good. Having the highest MePEG surface density (1.32 nm(-2)) , the shortest average distance between neighboring MePEG chain (0.87 nm) and the thicker fixed aqueous layer thickness (FALT, 5.16 nm), PEG5,000-PHDCA nanoparticles (80.0 nm) earned the strongest potency of decreasing uptake by macrophages and prolonging the half-life of rHuTNF-alpha in rat.

CONCLUSIONWithin the experimental limits, particle size and MePEG molecular weight had dramatic influence on in vitro macrophage uptake and in vivo long circulating properties of rHuTNF-alpha-loaded stealth nanoparticles.

Animals ; Cyanoacrylates ; chemistry ; Drug Carriers ; chemistry ; Drug Delivery Systems ; Macrophages ; physiology ; Male ; Mice ; Molecular Weight ; Nanoparticles ; Particle Size ; Phagocytosis ; drug effects ; Polyethylene Glycols ; chemistry ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacokinetics ; Tumor Necrosis Factor-alpha ; administration & dosage ; pharmacokinetics

AIMTo evaluate the pharmacokinetic profiles of the pharmacologically active primary amine metabolite of sibutramine, N-di-desmethyl sibutramine (BTS 54505) in Chinese origin.

METHODSAccording to a randomized cross-over design, a single oral dose of 20 mg of sibutramine hydrochloride capsule was given to 20 healthy Chinese young volunteers. After dosing, serial blood samples were collected for a period of 72 h. BTS 54505 concentration in plasma was analyzed by high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry.

RESULTSVarious pharmacokinetic parameters including AUC0-t, AUC0-infinity, Cmax, Tmax, T1/2, Kelm and MRT were determined for both test and reference capsules and found to be in good agreement with literature values.

CONCLUSIONThe test and reference sibutramine capsules were bioequivalent.

Administration, Oral ; Adult ; Area Under Curve ; Biological Availability ; Chromatography, High Pressure Liquid ; methods ; Cross-Over Studies ; Cyclobutanes ; administration & dosage ; blood ; pharmacokinetics ; Humans ; Male ; Serotonin Uptake Inhibitors ; administration & dosage ; pharmacokinetics ; Spectrometry, Mass, Electrospray Ionization

AIMTo investigate the pharmacokinetics of mycophenolic acid (MPA), an active metabolite of mycophenolate mofetil (MMF) in Chinese adult liver transplant patients.

METHODSThirty-eight liver transplant patients (male 30, female 8) receiving MMF 1.0 g, twice daily in accordance with the recommended regimen were included in this study. Plasma MPA concentrations were measured by high performance liquid chromatography at 0.5, 1, 1.5, 2, 4, 6, 8, 10 and 12 h after the administration of a single dose. Pharmacokinetic parameters were calculated with 3P97 software.

RESULTSThe plasma MPA concentration-time curve was characterized with an early sharp peak reached at 0.5 - 6.0 h after oral administration. And in some patients there was a small second peak due to enterohepatic circulation of mycophenolic acid glucuronide (MPAG), which underwent deglucuronidation and re-absorption as MPA at 4 to 12 h postdose. The mean peak plasma concentration (C(max)) and area under concentration-time curve (AUC(0-12 h)) were (12 +/- 7) microg x mL(-1) and (44 +/- 16) microg x h x mL(-1), respectively. However, a large variability of pharmacokinetic parameters existed in these patients.

CONCLUSIONIn view of the inter-individual variability of MMF pharmacokinetics, plasma MPA concentration should be monitored routinely after MMF administration for individual patient.

Adult ; Aged ; Area Under Curve ; Female ; Humans ; Immunosuppressive Agents ; pharmacokinetics ; Liver Transplantation ; Male ; Middle Aged ; Mycophenolic Acid ; analogs & derivatives ; pharmacokinetics

Objective To determine the risk factors related to tuberculosis infection among people living with HIV/AIDS and to develop strategies for preventing the co-infection.Methods A 1:2matched nested case-control study was carried out to analyze the influencing factors of tuberculosis among people living with HIV/AIDS.Results 1018 people living with HIV/AIDS were followed up for one year with a total number of 736.75 person-years,among them 62 tuberculosis cases were diagnosed.The incidence density of tuberculosis among people living with HIV/AIDS was 8.42 persons per 100 person-years.Factors as education level(OR=0.483),vaccination history of Bacille Calmette Guerin(OR=0.561),CD_4~+ count T-lymphocyte(OR=0.356),unemployment(OR=1.976),living alone(OR=2.646),and smoking(OR=2.215)were significantly related to the prevalence of tuberculosis among people living with HIV/AIDS.Conclusion High education level,with vaccination history of Bacille Calmette Guerin and high level of CD_4~+ T-lymphocyte count were protective factors while being unemployed,living alone,and smoking habit were risk factors related to the prevalence of tuberculosis among people living with HIV/AIDS.

OBJECTIVETo explore the relevant factors of the causes of sexual orientations of gay.

METHODFrom March to June 2013, 350 gays were recruited from one music bar and three bath centers where gays frequently visited in Changsha city, by proportional stratified sampling method. Meanwhile, another 332 males who identify themselves as non-homosexuality were also recruited considering the composition of ages, gender and educational background. Questionnaire survey was conducted to all the subjects, with 300 effective ones reclaimed. The questionnaire included the general demographic information, traits of character, the condition of foster in childhood and information of family members. The differences between the gays and non-homosexuality groups were analyzed to explore the causes of the sexual orientations of gays.

RESULTSThere were statistical significant differences between gays and non- homosexuality group on following indexes (χ(2) was 59.63, 5.90, 16.01, 84.99, 161.57, 77.77, 112.32, 190.84, 30.10 respectively, all of P < 0.05) :had a tender father and an impervious mother, were physically weak, not agile, physically inactive, attentive to details, highly conservative, not adventurous, and radical in childhood, were raised as girls before the age of 18, liked to dress as girls before the age of 18, don't liked to play toy knives and toy guns before the age of 18, suffered from sexual abuse before the age of 18 (e.g. forced to expose private parts or forced to have sex) by adults, had read or watched books or films about homosexual and experienced sexual pleasure from that before the age of 18. The rate of gays on these indexes was separately 62.3% (187/300), 57.7% (173/300) , 62.3% (187/300) , 63.0% (189/300), 67.3% (202/300) , 62.7% (189/300), 68.0% (204/300), 65.0% (195/300) and the rate on these indexes of non-homosexuality group was separately 21.3% (64/300), 28.0% (84/300) , 25.0% (75/300) , 12.7% (38/300), 31.3% (94/300), 17.7% (53/300) , 12.7% (38/300), 42.7% (128/300) . The rate of gays on these factors:the youngest boy in family, had the father or twin brothers who were homosexual or self identified as gay was 62.7% (188/300), 56.0% (168/300) and 62.0% (18/29) respectively; and the rate was 40.7% (122/300), 4.0% (12/300) and 20.0% (2/10), respectively among non-homosexuality group. The difference showed statistical significance (χ(2) was 34.52, 193.14, 5.27 respectively, all of P < 0.05).

CONCLUSIONThe correlative factor of sexual orientation of gays maybe was family relationship, tend and education since childhood, psychological characteristics, sexual experience during puberty.

Adult ; Homosexuality, Male ; psychology ; statistics & numerical data ; Humans ; Male ; Sexual Behavior ; statistics & numerical data ; Surveys and Questionnaires

OBJECTIVETo evaluate the effect of SMU.2055 gene on acid resistance of Streptococcus mutans.

METHODSA SMU.2055-dificient mutant strain of S. mutans was constructed using homologous recombination technique. The growth of the wild-type and mutant strains was monitored in both normal and acidic conditions. The lethal pH level, glycolysis, proton permeability, cell permeability and biofilm formation of the two strains were compared.

RESULTSPCR and sequence analyses verified the successful construction of the SMU.2055-dificient mutant strain. The growth and biofilm formation capacity of the mutant strain were obviously lowered in both normal and acidic conditions. The mutant strain also showed increased lethal pH level, proton permeability, and cell permeability with impaired H-ATPase activity in acidic conditions, but its minimum glycolytic pH remained unaffected.

CONCLUSIONThe SMU.2055-deficient S. mutans mutant exhibits a lowered acid resistance, which affects the growth, lethal pH, proton permeability, H-ATPase activity, cell permeability and biofilm formation but not the minimum glycolytic pH of the mutant strain.

Objective To explore the effects of airway peak pressure (Ppeak)guidance on the minimum laryngeal mask airway (LMA)intracuff pressure (ICP)setting during general anesthesia. Methods Sixty patients,aged 18-65 years,ASA physical status Ⅰ or Ⅱ,scheduled for elective gy-necological laparoscopic operation under general anesthesia were enrolled.The patients were randomly divided into pressure-regulated group (group P)and control group (group C)with 30 cases in each group.Size 4 Supreme LMA was inserted in after general anesthesia induction.Air was injected into the cuff to make ICP achieve 60 cm H2O.Volume-controlled ventilation was selected and Ppeak was recorded.In group P,all the gas in the LMA cuff was sucked out,and then air was injected in during expiration phase to make ICP achieve the level of Ppeak.If air leakage occurred,ICP was increased by 5 cm H2O each time until no gas leaked from the oropharynx.After pneumoperitoneum,the cuff was inflated to make ICP achieve 60 cm H2O and Ppeak was recorded once more.Then all the gas in the LMA cuff was sucked out,and air was injected into the cuff to make ICP achieve the level of Ppeak as the above method till the end of operation.In group C,ICP was maintained at 60 cm H2O.Ppeak, ICP and the intracuff gas volume were recorded before and after pneumoperitoneum.ICP during in-spiratory phase in the two groups was measured.Tidal volume during inspiration(Vti)and expiration (Vte)in the two groups were recorded,and the air leakage fraction (LF)was calculated as [(Vti-Vte)/Vti×100%].Laryngopharyngeal complications of all the patients in 24 hours after surgeries were also recorded.Results The intracuff gas volume before and after pneumoperitoneum and ICP were decreased significantly in group P compared with group C (P<0.05).There was no difference in LF between the two groups.Compared with group C,there were fewer patients with postoperative throat pain and swallow discomfort in group P (P<0.05).Conclusion ICP at the level of Ppeak plus 0-5 cm H2O during LMA ventilation can provide better sealing effect and less laryngopharyngeal com-plications.

Objective to explore the current situation and related influencing factors on the retention time of patients receiving methadone maintenance treatment (MMT). Methods Information on basic situation and daily treatment of the patients were collected from the 7 MMT clinics opened in the pro-two batch in Hunan province. Retention rate and influencing factors were analyzed. Results (1) The retention rates after 6 and 12 months of MMT became 72.06% and 49.65% respectively. (2) The retention rates of high-dosage group and low-dosage group were 85.03% and 68.03% after 6 months on MMT program while became 60.48% and 46.28% after 12 months of MMT respectively. (3) The mean retention time of HIV+ patients and HIV- patients were 9.46 months and 8.62 months respectively during the 12 months follow-up observation, showing a significant difference. (4) Patients who took large dose methadone, did not share needles, at older age or HIV+ , were prone to keep MMT at a long period. Conclusion The retention rates for 6 months and 12 months in the MMT program in Hunan province were similar to the national data. Dose, type of drug abuse, age and HIV status were related to the period of retention.