Search tips
Search criteria

Results 1-6 (6)

Clipboard (0)

Select a Filter Below

Year of Publication
Document Types
1.  Simultaneous Determination of Uric Acid and Xanthine Using a Poly(Methylene Blue) and Electrochemically Reduced Graphene Oxide Composite Film Modified Electrode 
Poly(methylene blue) and electrochemically reduced graphene oxide composite film modified electrode (PMB-ERGO/GCE) was successfully fabricated by electropolymerization and was used for simultaneous determination of uric acid (UA) and xanthine (Xa). Based on the excellent electrocatalytic activity of PMB-ERGO/GCE, the electrochemical behaviors of UA and Xa were studied by cyclic voltammetry (CV) and square wave voltammetry (SWV). Two anodic sensitive peaks at 0.630 V (versus Ag/AgCl) for UA and 1.006 V (versus Ag/AgCl) for Xa were given by CV in pH 3.0 phosphate buffer. The calibration curves for UA and Xa were obtained in the range of 8.00 × 10−8~4.00 × 10−4 M and 1.00 × 10−7~4.00 × 10−4 M, respectively, by SWV. The detection limits for UA and Xa were 3.00 × 10−8 M and 5.00 × 10−8 M, respectively. Finally, the proposed method was applied to simultaneously determine UA and Xa in human urine with good selectivity and high sensitivity.
PMCID: PMC4244694  PMID: 25436174
2.  The Ecology of Medical Care in Beijing 
PLoS ONE  2013;8(12):e82446.
We presented the pattern of health care consumption, and the utilization of available resources by describing the ecology of medical care in Beijing on a monthly basis and by describing the socio-demographic characteristics associated with receipt care in different settings.
A cohort of 6,592 adults, 15 years of age and older were sampled to estimate the number of urban-resident adults per 1,000 who visited a medical facility at least once in a month, by the method of three-stage stratified and cluster random sampling. Separate logistic regression analyses assessed the association between those receiving care in different types of setting and their socio-demographic characteristics.
On average per 1,000 adults, 295 had at least one symptom, 217 considered seeking medical care, 173 consulted a physician, 129 visited western medical practitioners, 127 visited a hospital-based outpatient clinic, 78 visited traditional Chinese medical practitioners, 43 visited a primary care physician, 35 received care in an emergency department, 15 were hospitalized. Health care seeking behaviors varied with socio-demographic characteristics, such as gender, age, ethnicity, resident census register, marital status, education, income, and health insurance status. In term of primary care, the gate-keeping and referral roles of Community Health Centers have not yet been fully established in Beijing.
This study represents a first attempt to map the medical care ecology of Beijing urban population and provides timely baseline information for health care reform in China.
PMCID: PMC3855438  PMID: 24340029
3.  Associations Between Polymorphisms in the Glucocorticoid-Receptor Gene and Cardiovascular Risk Factors in a Chinese Population 
Journal of Epidemiology  2013;23(5):389-395.
Glucocorticoid is an important regulator of energy homeostasis. Glucocorticoid receptor (GR) gene polymorphisms that contribute to variability in glucocorticoid sensitivity have been identified. We explored the associations of single-nucleotide polymorphisms (SNPs) of the GR gene with traditional cardiovascular risk factors in the Chinese Han population.
We recruited 762 consecutive adults who underwent a regular physical examination at Beijing Xuanwu Hospital. Blood pressure, glucose, lipid levels (total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein [LDL] cholesterol and triglycerides), body mass index (BMI), and waist-to-hip ratio were measured. Fourteen tag SNPs and 5 functional SNPs were selected and genotyped using the high-throughput Sequenom genotyping platform. Differences between genotypes/alleles for each SNP were adjusted for sex and age and tested using a general linear model procedure. Various models of inheritance, including additive, dominant, and recessive, were tested.
Among the 19 SNPs examined, 5 markers were associated with cardiovascular risk factors. The rs41423247 GG genotype and the rs7701443 AA genotype were associated with higher BMI and systolic blood pressure (P < 0.0004), and the rs17209251 GG genotype was associated with higher systolic blood pressure (P < 0.0004). Lower systolic blood pressure, total cholesterol, and LDL cholesterol were observed among rs10052957 A allele carriers (P < 0.0004), and lower plasma glucose and LDL-cholesterol concentrations were observed among rs2963156 TT carriers (P < 0.0004).
Polymorphism of the GR gene was associated with cardiovascular risk factors and may contribute to susceptibility to cardiovascular disease.
PMCID: PMC3775534  PMID: 23892712
glucocorticoid receptor gene; polymorphism; cardiovascular disease; risk factor
4.  Adolescent social isolation influences cognitive function in adult rats☆ 
Neural Regeneration Research  2013;8(11):1025-1030.
Adolescence is a critical period for neurodevelopment. Evidence from animal studies suggests that isolated rearing can exert negative effects on behavioral and brain development. The present study aimed to investigate the effects of adolescent social isolation on latent inhibition and brain-derived neurotrophic factor levels in the forebrain of adult rats. Male Wistar rats were randomly divided into adolescent isolation (isolated housing, 38–51 days of age) and social groups. Latent inhibition was tested at adulthood. Brain-derived neurotrophic factor levels were measured in the medial prefrontal cortex and nucleus accumbens by an enzyme-linked immunosorbent assay. Adolescent social isolation impaired latent inhibition and increased brain-derived neurotrophic factor levels in the medial prefrontal cortex of young adult rats. These data suggest that adolescent social isolation has a profound effect on cognitive function and neurotrophin levels in adult rats and may be used as an animal model of neurodevelopmental disorders.
PMCID: PMC4145882  PMID: 25206396
neural regeneration; adolescence; social isolation; latent inhibition; brain-derived neurotrophic factor; medial prefrontal cortex; nucleus accumbens; adult; cognitive function; neurodevelopmental disorders; grants-supported paper; neuroregeneration
5.  Prevalence and Factors Associated with Hepatitis B Immunization and Infection among Men Who Have Sex with Men in Beijing, China 
PLoS ONE  2012;7(10):e48219.
Among the Chinese population of 1.3 billion, there are an estimated 93 million carriers of hepatitis B virus (HBV). Men who have sex with men (MSM) are at increased risk for HBV infection; however, the prevalence of HBV immunization and infection among Chinese MSM remains undetermined.
A cross-sectional survey of 1,114 eligible participants was conducted in Beijing, China. Multiple methods were used to recruit study participants. Demographic information and potential correlated factors were collected by questionnaire. Additionally, blood specimens were collected and tested for sexually transmitted infections and serologic markers of hepatitis B immunization and infection.
Laboratory data were available for 1,111 participants (99.7%), the prevalence of hepatitis B immunization was 38.9%, and 26.5% had serologic markers of HBV infection. Multivariate analyses indicated that higher education level, smaller number of male sex partners in the past 12 months, reported diagnosis of sexually transmitted disease (STD), and history of blood donation were independently associated with HBV immunization. Absence of steady male sex partner(s) in the past 12 months, and reported diagnosis of STD were shown to be independently associated with HBV infection. MSM positive for HBV infection were more likely to have past or current syphilis infection.
Low prevalence of HBV immunization and high prevalence of HBV infection among Chinese MSM and a correlation between sexual risk factors and hepatitis B infection indicate that comprehensive preventative measures for HBV among MSM, including blood donor and HIV-STD clinic vaccination programs as well as targeted health education campaigns should be developed in China.
PMCID: PMC3485055  PMID: 23133573
6.  Expression of human amyloid precursor protein in the skeletal muscles of Drosophila results in age- and activity-dependent muscle weakness 
BMC Physiology  2011;11:7.
One of the hallmarks of Alzheimer's disease, and several other degenerative disorders such as Inclusion Body Myositis, is the abnormal accumulation of amyloid precursor protein (APP) and its proteolytic amyloid peptides. To better understand the pathological consequences of inappropriate APP expression on developing tissues, we generated transgenic flies that express wild-type human APP in the skeletal muscles, and then performed anatomical, electrophysiological, and behavioral analysis of the adults.
We observed that neither muscle development nor animal longevity was compromised in these transgenic animals. However, human APP expressing adults developed age-dependent defects in both climbing and flying. We could advance or retard the onset of symptoms by rearing animals in vials with different surface properties, suggesting that human APP expression-mediated behavioral defects are influenced by muscle activity. Muscles from transgenic animals did not display protein aggregates or structural abnormalities at the light or transmission electron microscopic levels. In agreement with genetic studies performed with developing mammalian myoblasts, we observed that co-expression of the ubiquitin E3 ligase Parkin could ameliorate human APP-induced defects.
These data suggest that: 1) ectopic expression of human APP in fruit flies leads to age- and activity-dependent behavioral defects without overt changes to muscle development or structure; 2) environmental influences can greatly alter the phenotypic consequences of human APP toxicity; and 3) genetic modifiers of APP-induced pathology can be identified and analyzed in this model.
PMCID: PMC3112101  PMID: 21518451
amyloid precursor protein (APP); Drosophila; muscle; mitochondria; electron microscopy; apoptosis; Parkin

Results 1-6 (6)