PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (46)
 

Clipboard (0)
None

Select a Filter Below

Year of Publication
Document Types
1.  Association of Egr3 genetic polymorphisms and coronary artery disease in the Uygur and Han of China 
Background
Endothelial cell activation and dysfunction are the foundation of atherosclerosis, including coronary artery disease (CAD). Endothelial cell activation is mediated by the level of gene transcription. Early growth response 3 (Egr3) is a critical determinant of vascular endothelial growth factor (VEGF) signalling in activated endothelial cells. If endothelial cells are excessively activated, it may lead to vasculopathic diseases, such as pathologic angiogenesis, inflammation, and atherosclerosis. The aim of the present study was to assess the association between the Egr3 gene polymorphisms and CAD.
Methods
Two independent case–control studies that involved the Han group (409 CAD patients and 351 control subjects) and the Uygur group (299 CAD patients and 303 control subjects) analysed the relationship between Egr3 SNPs (rs1996147 and rs1008949) and CAD. Genotyping was undertaken using the TaqMan SNP genotyping assay.
Results
The entire Uygur group and the males in the Uygur group showed a higher frequency of the A allele (rs1996147) in CAD patients than in the control subjects (P = 0.003 and P = 0.005, respectively). Additionally, the distribution of the recessive model of rs1996147 (AA vs GG + AG) for the total sample and the males was significantly different between CAD patients and control participants (P = 0.002 and P = 0.003, respectively), and the difference remained statistically significant following multivariate adjustment (Total: OR = 1.705; 95% CI: 1.166-2.494, P = 0.006; males: OR = 1.908, 95% CI: 1.189-3.062, P = 0.007). However, for Uygur females, we did not observe a difference in the allele frequency or genotypic distribution of rs1996147 between CAD patients and control participants. Similarly, the distribution of the rs1996147 allele frequency or genotypes showed no significant difference between patients with CAD and control participants in the Han group. The distribution of rs1008949 genotypes, dominant model, recessive model, and allele frequency did not show a significant difference between patients with CAD and the control subjects in the Han and Uygur groups.
Conclusion
rs1996147 may be a novel polymorphism of the Egr3 gene associated with CAD in males of the Chinese Uygur population.
doi:10.1186/1476-511X-13-84
PMCID: PMC4040484  PMID: 24886494
Egr3; Coronary artery disease; Polymorphism
2.  Folate receptor-targeted liposomes enhanced the antitumor potency of imatinib through the combination of active targeting and molecular targeting 
Purpose
Imatinib inhibits platelet-derived growth factor receptor (PDGFR), and evidence shows that PDGFR participates in the development and progression of cervical cancer. Although imatinib has exhibited preclinical activity against cervical cancer, only minimal clinical therapeutic efficacy was observed. This poor therapeutic efficacy may be due to insufficient drug delivery to the tumor cells and plasma protein binding. Therefore, the purpose of this study was to explore a novel folate receptor (FR)-targeted delivery system via imatinib-loaded liposomes to enhance drug delivery to tumor cells and to reduce plasma protein binding.
Methods
Imatinib was remote-loaded into FR-targeted liposomes which were prepared by thin film hydration followed by polycarbonate membrane extrusion. Encapsulation efficiency, mean size diameter, and drug retention were characterized and cellular uptake, cell cytotoxicity, and cell apoptosis on cervical cancer HeLa cells were evaluated. Comparative pharmacokinetic studies were also carried out with FR-targeted imatinib liposomes, simple imatinib liposomes, and free imatinib.
Results
High encapsulation efficiency (>90%), appropriate mean particle size (143.5 nm), and zeta potential (−15.97 mV) were obtained for FR-targeted imatinib liposomes. The drug release profile showed minimal imatinib leakage (<5%) in phosphate-buffered saline (PBS) at pH =7.4 within 72 hours of incubation, while more leakage (>25%) was observed in PBS at pH =5.5. This indicates that these liposomes possess a certain degree of pH sensitivity. Cytotoxicity assays demonstrated that the FR-targeted imatinib liposomes promoted a six-fold IC50 reduction on the non-targeted imatinib liposomes from 910 to 150 μM. In addition, FR-targeted imatinib liposomes enhanced HeLa cell apoptosis in vitro compared to the non-targeted imatinib liposomes. Pharmacokinetic parameters indicated that both targeted and non-targeted liposomes exhibited long circulation properties in Kunming mice.
Conclusion
These findings indicate that the nano-sized FR-targeted PDGFR antagonist imatinib liposomes may constitute a promising strategy in cervical cancer therapy through the combination of active targeting and molecular targeting.
doi:10.2147/IJN.S60178
PMCID: PMC4019625  PMID: 24855354
liposomes; imatinib; folate receptor; tumor targeting; PDGFR
3.  Association between the APC gene D1822V variant and the genetic susceptibility of colorectal cancer 
Oncology Letters  2014;8(1):139-144.
Adenomatous polyposis coli (APC) gene polymorphisms are believed to contribute to tumor susceptibility. However, the association between genetic variants (A/T) in the APC gene D1822V polymorphism and colorectal cancer (CRC) susceptibility remains unknown. To determine this association, a case-control study was performed. The genotype of the APC gene D1822V variants was analyzed by DNA sequencing in blood samples collected from 196 patients with CRC and 279 healthy subjects. There were no significant associations between the case and control groups in the distribution of AT [odds ratio (OR), 0.604; 95% confidence interval (CI), 0.355–1.029) and TT genotypes (OR, 0.438; 95% CI, 0.045–4.247) relative to the AA genotype. The ratio of the T allele was significantly lower (P=0.047) in the case group compared with the control group (OR, 0.611; 95% CI, 0.374–0.997), indicating that the T allele conferred a protective effect in CRC. The frequency of the AT genotype among the subjects diagnosed at >45 years of age was lower than those diagnosed at a younger age (P<0.05). The present study demonstrates that the T allele of the D1822V polymorphism may exert a protective effect against CRC, however, these findings require further validation in a larger sample size.
doi:10.3892/ol.2014.2102
PMCID: PMC4063591  PMID: 24959234
colorectal cancer; APC gene; single nucleotide polymorphism; genetic susceptibility
4.  Hacking on decoy-state quantum key distribution system with partial phase randomization 
Scientific Reports  2014;4:4759.
Quantum key distribution (QKD) provides means for unconditional secure key transmission between two distant parties. However, in practical implementations, it suffers from quantum hacking due to device imperfections. Here we propose a hybrid measurement attack, with only linear optics, homodyne detection, and single photon detection, to the widely used vacuum + weak decoy state QKD system when the phase of source is partially randomized. Our analysis shows that, in some parameter regimes, the proposed attack would result in an entanglement breaking channel but still be able to trick the legitimate users to believe they have transmitted secure keys. That is, the eavesdropper is able to steal all the key information without discovered by the users. Thus, our proposal reveals that partial phase randomization is not sufficient to guarantee the security of phase-encoding QKD systems with weak coherent states.
doi:10.1038/srep04759
PMCID: PMC3996487  PMID: 24755767
5.  Repair of Segmental Bone Defect Using Totally Vitalized Tissue Engineered Bone Graft by a Combined Perfusion Seeding and Culture System 
PLoS ONE  2014;9(4):e94276.
Background
The basic strategy to construct tissue engineered bone graft (TEBG) is to combine osteoblastic cells with three dimensional (3D) scaffold. Based on this strategy, we proposed the “Totally Vitalized TEBG” (TV-TEBG) which was characterized by abundant and homogenously distributed cells with enhanced cell proliferation and differentiation and further investigated its biological performance in repairing segmental bone defect.
Methods
In this study, we constructed the TV-TEBG with the combination of customized flow perfusion seeding/culture system and β-tricalcium phosphate (β-TCP) scaffold fabricated by Rapid Prototyping (RP) technique. We systemically compared three kinds of TEBG constructed by perfusion seeding and perfusion culture (PSPC) method, static seeding and perfusion culture (SSPC) method, and static seeding and static culture (SSSC) method for their in vitro performance and bone defect healing efficacy with a rabbit model.
Results
Our study has demonstrated that TEBG constructed by PSPC method exhibited better biological properties with higher daily D-glucose consumption, increased cell proliferation and differentiation, and better cell distribution, indicating the successful construction of TV-TEBG. After implanted into rabbit radius defects for 12 weeks, PSPC group exerted higher X-ray score close to autograft, much greater mechanical property evidenced by the biomechanical testing and significantly higher new bone formation as shown by histological analysis compared with the other two groups, and eventually obtained favorable healing efficacy of the segmental bone defect that was the closest to autograft transplantation.
Conclusion
This study demonstrated the feasibility of TV-TEBG construction with combination of perfusion seeding, perfusion culture and RP technique which exerted excellent biological properties. The application of TV-TEBG may become a preferred candidate for segmental bone defect repair in orthopedic and maxillofacial fields.
doi:10.1371/journal.pone.0094276
PMCID: PMC3984127  PMID: 24728277
6.  C-kit induces epithelial-mesenchymal transition and contributes to salivary adenoid cystic cancer progression 
Oncotarget  2014;5(6):1491-1501.
Epithelial–mesenchymal transition (EMT) is associated with salivary adenoid cystic cancer (ACC) progression and metastasis. Here, we report that ectopic overexpression of c-kit in ACC cell lines is sufficient for acquisition of mesenchymal traits, enhanced cell invasion, along with stem cell properties defined by the presence of a CD133 + /CD44 + cell subpopulation. c-kit positively regulated expression of known EMT inducers, also activating TGF-β to contribute to EMT. c-kit itself was induced by TGF-β in ACC cell lines and required for TGF-β–induced EMT. Xenograft experiments showed that c-kit cooperated with oncogenic Ras to promote tumorigenesis in vivo. Finally, in human specimens of ACC, we found that c-kit was abnormally overexpressed and correlated with the prognosis of ACC. Our findings define an important function for c-kit in ACC progression by orchestrating EMT, and they implicate this gene product as a marker of poor prognosis in this disease.
PMCID: PMC4039226  PMID: 24721839
salivary adenoid cystic cancer; epithelial–mesenchymal transition (EMT); c-kit; cancer stem cell; metastasis
7.  Social influences on Cigarette Smoking Among Mainland Chinese and Chinese Americans: A Comparative Study 
The purpose of this cross-national study was to determine the leading social influences on smoking among Chinese Americans and mainland Chinese adults with the aim of improving prevention and intervention strategies to reduce smoking rates. A comparative cross-sectional design was used and a stratified-cluster sampling technique was employed in identifying the study sample. An 80-item questionnaire was administered in Chinese to 1222 participants, 812 in China and 410 in the U.S. Data were analyzed using descriptive and inferential statistical tests. Results contain comparative data on social influences of smoking among Chinese Americans and mainland Chinese, as well as factors influencing smoking behavior which include cultural beliefs, gender roles, and family relationship dynamics. Grandparents were influential and significantly correlated with current smokers in China. Findings indicate differential effects of social influences on smoking behavior. Similarities and differences provide a basis for improving and/or developing smoking intervention programs of mutual benefit to China and the U.S..
PMCID: PMC3914219  PMID: 24511220
8.  Prevalence, awareness, treatment and control of dyslipidemia among adults in Northwestern China: the cardiovascular risk survey 
Aim
The aim of this study was to estimate the prevalence, awareness, treatment, and control of dyslipidemia in Xinjiang, China.
Method
Stratified sampling method was used to select a representative sample of the general population including Chinese Han, Uygur, and Kazak in this geographic area. Seven cities were chosen. Based on the government records of registered residences, one participant was randomly selected from each household. The eligibility criterion for the study was ≥ 35 years of age.
Results
A total of 14,618 participants (5,757 Han, 4,767 Uygur, and 4,094 Kazak), were randomly selected from 26 villages in 7 cities. The prevalence of dyslipidemia was 52.72% in the all participants. The prevalence of dyslipidemia was higher in Han than that in the other two ethnic (58.58% in Han, 48.27% in Uygur, and 49.60% in Kazak, P < 0.000). The prevalence of dyslipidemia was higher in men than that in women (56.4% vs. 49.3%, P < 0.000). Among the participants with dyslipidemia, the proportion of those who aware, treat, control of dyslipidemia were 53.67%, 22.51%, 17.09% in Han, 42.19%, 27.78%, 16.20% in Uygur, 37.02%, 21.11%, 17.77% in Kazak.
Conclusion
Dyslipidemia is highly prevalent in Xinjiang. The proportion of participants with dyslipidemia who were aware, treated, and controlled is unacceptably low. These results underscore the urgent need to develop national strategies to improve the prevention, detection, and treatment of dyslipidemia in Xinjiang.
doi:10.1186/1476-511X-13-4
PMCID: PMC3895843  PMID: 24393232
Dyslipidemia; Prevalence; Awareness; Treatment; Control
9.  Effects of Upregulation of Hsp27 Expression on Oocyte Development and Maturation Derived from Polycystic Ovary Syndrome 
PLoS ONE  2013;8(12):e83402.
Heat shock protein 27 (Hsp27) is a heat shock protein family member which can inhibit apoptosis. Our previous studies reported down-regulated Hsp27 in ovarian tissue derived from women with polycystic ovary syndrome (PCOS) however, the exact effect of Hsp27 on oocyte maturation and developmental competence in PCOS is unclear. The effect of Hsp27 over-expression was studied in vitro using oocytes derived from PCOS patients. An artificial GFP-plasmid was injected into human oocyte to increase Hsp27 protein level. Oocyte maturation was evaluated by morphological observation. Mature oocytes were fertilized by intracytoplasmic sperm injection (ICSI) and embryonic developmental competence was evaluated. Critical apoptotic factors and cytokines were measured at both the mRNA and protein level. Our results revealed that Overexpression of HSP27 lowered the maturation rate of oocytes derived from PCOS patients. Meanwhile, fertilization rate and high quality embryo rate were similar between the Hsp27 overexpressing group and controls; however, the blastocyst formation rate in this group was significantly higher than control. Expression analysis revealed that the oocyte-secreted factors, BMP15 and GDF9, and the apoptotic-related regulators, Caspase 3, 8 and 9, were all significantly decreased in Hsp27 overexpressing oocytes. In conclusion, upregulation of Hsp27 inhibits oocyte maturation from PCOS patients, but improves embryonic developmental potential.
doi:10.1371/journal.pone.0083402
PMCID: PMC3877038  PMID: 24391762
10.  Prevalence of major cardiovascular risk factors and adverse risk profiles among three ethnic groups in the Xinjiang Uygur Autonomous Region, China 
Background
Prevalence of cardiovascular disease (CVD) risk factors have been scarcely studied in Xinjiang, a multi-ethnic region.
Methods
Multi-ethnic, cross-sectional cardiovascular risk survey study in Xinjiang, including individuals of Uygur (n = 4695), Han (n = 3717) and Kazakh (n = 3196) ethnicities, aged 35-74 years. Analyses involved 11,608 participants with complete data enrolled between October 2007 and March 2010.
Results
There were differences in age-standardized prevalence of CVD risk factors between the three groups (all P < 0.001). Hypertension, obesity and smoking rates were higher among Kazakh (54.6%, 24.5%, and 35.8%, respectively). Dyslipidemia prevalence was higher among Uygur (54.3%), and diabetes prevalence was higher among Hans (7.1%). Age-standardized prevalence of adverse CVD risk profiles was different across different ethnicities. Compared with the Han participants, the Uygur and Kazakh had more CVD risk factors (P < 0.001). Compared with the Han participants, the adjusted odds ratios of 1, 2, and ≥3 risk factors profiles for Kazakh and Uygur participants were higher (all P < 0.001).
Conclusions
The present study showed the pervasive burden of CVD risk factors in all participant groups in the Xinjiang region. Three major ethnic groups living in Xinjiang had striking differences in the prevalence of major CVD risk factors and adverse risk profiles. Ethnic-specific strategies should be developed to prevent CVD in different ethnic groups, as well as to develop strategies to prevent future development of adverse CVD risk factors at a younger age.
doi:10.1186/1476-511X-12-185
PMCID: PMC3866600  PMID: 24341701
Cardiovascular disease; Risk factors; Disparities; Ethnicity; Epidemiology
11.  Modified Uterine Allotransplantation and Immunosuppression Procedure in the Sheep Model 
PLoS ONE  2013;8(11):e81300.
Objective
To develop an orthotopic, allogeneic, uterine transplantation technique and an effective immunosuppressive protocol in the sheep model.
Methods
In this pilot study, 10 sexually mature ewes were subjected to laparotomy and total abdominal hysterectomy with oophorectomy to procure uterus allografts. The cold ischemic time was 60 min. End-to-end vascular anastomosis was performed using continuous, non-interlocking sutures. Complete tissue reperfusion was achieved in all animals within 30 s after the vascular re-anastomosis, without any evidence of arterial or venous thrombosis. The immunosuppressive protocol consisted of tacrolimus, mycophenolate mofetil and methylprednisolone tablets. Graft viability was assessed by transrectal ultrasonography and second-look laparotomy at 2 and 4 weeks, respectively.
Results
Viable uterine tissue and vascular patency were observed on transrectal ultrasonography and second-look laparotomy. Histological analysis of the graft tissue (performed in one ewe) revealed normal tissue architecture with a very subtle inflammatory reaction but no edema or stasis.
Conclusion
We have developed a modified procedure that allowed us to successfully perform orthotopic, allogeneic, uterine transplantation in sheep, whose uterine and vascular anatomy (apart from the bicornuate uterus) is similar to the human anatomy, making the ovine model excellent for human uterine transplant research.
doi:10.1371/journal.pone.0081300
PMCID: PMC3838404  PMID: 24278415
12.  Appropriate Body Mass Index and Waist Circumference Cutoffs for Categorization of Overweight and Central Adiposity among Uighur Adults in Xinjiang 
PLoS ONE  2013;8(11):e80185.
Objective
The current overweight and central adiposity guidelines based on Western populations were not consistent with many studied based on the Asian populations. Uighur people live in Xinjiang Uighur Autonomous Region which is located in the center of Asia. Their overweight and central cutoffs were largely unknown. We aimed to identify cutoffs for body mass index (BMI; in kg/m2) and waist circumference (WC; in cm) for categorization of overweight and central adiposity among Uighur adults in Xinjiang.
Methods
4767 Uighur participants were selected from the Cardiovascular Risk Survey (CRS) which was carried out from October 2007 to March 2010. The age of the participants were from 35 to 101 years old with the mean age of 50.09 years. Anthropometric data, blood pressure, serum concentration of serum total cholesterol, triglyceride, low density lipoprotein (LDL), high density lipoprotein (HDL) and fasting glucose were documented. The prevalence, sensitivity, specificity and distance on the receiver operating characteristic (ROC) curve of each BMI and waist circumference values were calculated.
Results
The prevalence of hypertension, hypercholesterolemia and hypertriglyceridemia were higher with higher BMI for both men and women. The prevalence of hypertension and hypercholesterolemia were higher with higher waist circumference for both men and women. In women, the prevalence of hypertriglyceridemia was noticed to increase as the waist circumference increased. The shortest distance in the receiver operating characteristic curves for hypertension, dyslipidemia, diabetes, or ≥ 2 of these risk factors suggested a BMI cutoff of 26 and a waist circumference cutoff of 90 cm for both men and women.
Conclusions
Higher cutoffs for BMI and waist circumference are needed in the identification of Uighur patients at high risk of cardiovascular disease.
doi:10.1371/journal.pone.0080185
PMCID: PMC3820640  PMID: 24244645
13.  A novel polymorphism (901G > a) of C5L2 gene is associated with coronary artery disease in Chinese Han and Uyghur population 
Background
C5L2, a G protein-coupled receptor (GPCR), has been demonstrated to be a ligand for acylation-stimulating protein (ASP). The aim of the present study is to evaluate the association of a novel variation (901A > G) of C5L2 gene with coronary artery disease (CAD).
Methods
We identified a novel single nucleotide polymorphism (SNP), (901G > A), in exon 2 using a polymerase chain reaction direct-sequencing method. This nucleotide change causes the amino-acid order from Arginine to glutaminate at codon 300. We analyzed the relationship between this SNP and CAD in two independent case–control studies: one was in a Han population (492 CAD patients and 577 control subjects) and the other was in a Uygur population (319 CAD patients and 554 control subjects).
Results
The frequency of AG genotype in CAD subjects was less than that in the control subjects not only in Han (1.8% vs 8.6%, P < 0.001, OR = 0.143, 95% CI: 0.068 ~ 0.302) but also in Uygur population (0.9% vs 5.2%, P = 0.001, OR = 0.246, 95% CI: 0.072 ~ 0.837). After adjustment for known CAD risk factors such as hypertension, diabetes, smoking, age and gender, the difference remained significant.
Conclusion
The 901G > A polymorphism of C5L2 may be a genetic maker of CAD in the Han and Uygur population in western China.
doi:10.1186/1476-511X-12-139
PMCID: PMC3850511  PMID: 24073849
Acylation stimulating protein; C5L2; Triglyceride synthesis; Coronary artery disease
14.  Pathways of Breast Cancer Screening Among Chinese American Women 
Objective
The purpose of this community-based study was to develop a structural equation model for factors contributing to breast cancer screening among Chinese American women.
Methods
A cross-sectional design included a sample of 440 Chinese American women aged 40 years and older. The initial step involved use of confirmatory factor analysis, which included the following variables: access/satisfaction with health care, enabling, predisposing, and cultural and health belief factors. Structural equation model analyses were conducted to evaluate factors related to breast cancer screening in Chinese American women.
Results
Initial univariate analyses indicated that women without health insurance were significantly more likely to report being never-screened compared to women with health insurance. Structural equation modeling techniques were used to evaluate the utility of the Sociocultural Health Behavior model in understanding breast cancer screening among Chinese American women. Results indicated that enabling and predisposing factors were significantly and positively related to breast cancer screening. Cultural factors were significantly associated with enabling factors and satisfaction with healthcare. Overall, the proposed model explained 34% of the variance in breast cancer screening among Chinese American women.
Conclusions
The model highlights the significance of enabling and predisposing factors in understanding breast cancer screening behaviors among Chinese American women. In addition, cultural factors were associated with enabling factors, reinforcing the importance of providing translation assistance to Chinese women with poor English fluency and increasing awareness of the critical role of breast cancer screening. Partnering with community organizations may help to facilitate and enhance the screening rates.
doi:10.4172/2161-0711.1000209
PMCID: PMC3762685  PMID: 24013711
Mammograms; Breast cancer screening; Chinese women
15.  Genetic variation in Tanis was associated with elevating plasma triglyceride level in Chinese nondiabetic subjects 
Background
The association of genetic polymorphisms of Tanis with triglyceride concentration in human has not been thoroughly examined. We aimed to investigate the relationship between triglyceride concentrations and Tanis genetic polymorphisms.
Methods
All participants (n=1497) selected from subjects participating in the Cardiovascular Risk Survey (CRS) study were divided into two groups according to ethnicity (Han: n=1059; Uygur: n= 438). Four tagging SNPs (rs12910524, rs1384565, rs2101171, rs4965814) of Tanis gene were genotyped using TaqMan® assays from Applied Biosystems following the manufacturer’s suggestions and analyzed in an ABI 7900HT Fast Real-Time PCR System.
Results
We found that the SNP rs12910524 was associated with triglyceride levels by analyses of a dominant model (P<0.001), recessive model (P <0.001) and additive model (P < 0.001) not only in Han ethnic but also in Uygur ethnic group, and the difference remained significant after the adjustment of sex, age, alcohol intake, smoking, BMI and plasma glucose (GLU) level (All P < 0.001). However, this relationship was not observed in rs1384565, rs2101171, and rs4965814 before and after multivariate adjustment (All P > 0.05). Furthermore, there were significant interactions between rs12910524 and GLU on TG both in Han (P=0.001) and Uygur population (P=2.60×10-4).
Conclusion
Our results indicated that the rs12910524 in the Tanis gene was associated with triglyceride concentrations in subjects without diabetes in China.
doi:10.1186/1476-511X-12-97
PMCID: PMC3706366  PMID: 23829426
Genetics; Tanis; Triglyceride; Diabetes; Polymorphisms
16.  Serotype Distribution and Antimicrobial Resistance of Streptococcus pneumoniae Isolates Causing Invasive Diseases from Shenzhen Children’s Hospital 
PLoS ONE  2013;8(6):e67507.
Objective
To provide guidance for clinical disease prevention and treatment, this study examined the epidemiology, antibiotic susceptibility, and serotype distribution of Streptococcus pneumoniae (S. pneumoniae) associated with invasive pneumococcal diseases (IPDs) among children less than 14 years of age in Shenzhen, China.
Materials and Methods
All the clinical strains were isolated from children less than 14 years old from January 2009 to August 2012. The serotypes and antibiotic resistance of strains of S. pneumoniae were determined using the capsular swelling method and the E-test.
Results
A total of 89 strains were isolated and 87 isolates were included. The five prevailing serotypes were 19F (28.7%), 14 (16.1%), 23F (11.5%), 19A (9.2%) and 6B (6.9%). The most common sequence types (ST) were ST271 (21.8%), ST876 (18.4%), ST320 (8.0%) and ST81 (6.9%) which were mainly related to 19F, 14, 19A and 23F, respectively. The potential coverage by 7-, 10-, and 13-valent pneumococcal conjugate vaccine were 77.0%, 77.0%, and 89.7%, respectively. Among the 87 isolates investigated, 11.5% were resistant to penicillin, and for meningitis isolates, the resistance rate was 100%. Multi-drug resistance (MDR) was exhibited by 49 (56.3%) isolates. Eighty-four isolates were resistance to erythromycin, among which, 56 (66.7%) carried the ermB gene alone and 28 (33.3%) expressed both the ermB and mefA/E genes.
Conclusions
The potential coverage of PCV13 is higher than PCV7 and PCV10 because high rates of serotypes 19A and 6A in Shenzhen. The clinical treatment of IPD needs a higher drug concentration of antibiotics. Continued surveillance of the antimicrobial susceptibility and serotypes distribution of IPD isolates may be necessary.
doi:10.1371/journal.pone.0067507
PMCID: PMC3696094  PMID: 23840728
17.  Pathways of cervical cancer screening among Chinese women 
Background
The purpose of this community-based study was to develop a structural equation model for factors contributing to cervical cancer screening among Chinese American women.
Methods
A cross-sectional design included a sample of 573 Chinese American women aged 18 years and older. The initial step involved use of confirmatory factor analysis, that included the following variables: access to and satisfaction with health care, and enabling and predisposing cultural and health beliefs. Structural equation model analyses were conducted on factors related to cervical cancer screening.
Results
Age, marital status, employment, household income, and having health insurance, but not educational level, were significantly related to cervical screening status. Predisposing and enabling factors were positively associated with cervical cancer screening. The cultural factor was significantly related to the enabling factor or the satisfaction with health care factor.
Conclusion
This model highlights the significance of sociocultural factors in relation to cervical cancer screening. These factors were significant, with cultural, predisposing, enabling, and health belief factors and access to and satisfaction with health care reinforcing the need to assist Chinese American women with poor English fluency in translation and awareness of the importance of cervical cancer screening. Community organizations may play a role in assisting Chinese American women, which could enhance cervical cancer screening rates.
doi:10.2147/IJWH.S45405
PMCID: PMC3702238  PMID: 23843708
Papanicolaou test; cervical cancer screening; Chinese women
18.  An Examination of the Electrostatic Interactions Between the N-Terminal Tail of the Brome Mosaic Virus Coat Protein and Encapsidated RNAs 
Journal of Molecular Biology  2012;419(5):284-300.
The coat protein of positive-stranded RNA viruses often contains a positively-charged tail that extends toward the center of the capsid and interacts with the viral genome. Electrostatic interaction between the tail and the RNA has been postulated as a major force in virus assembly and stabilization. The goal of this work is to examine the correlation between electrostatic interaction and the amount of RNA packaged in the tripartite Brome Mosaic Virus (BMV). Nanoindentation experiment using atomic force microscopy showed that the stiffness of BMV virions with different RNAs varied by a ten-fold higher range than would be predicted by electrostatics. BMV mutants with decreased positive charges encapsidated lower amounts of RNA while mutants with increased positive charges packaged additional RNAs up to ~900 nucleotides. However, the extra RNAs included truncated BMV RNAs, an additional copy of RNA4, potential cellular RNAs, or a combination of the three, indicating that change in the charge of the capsid could result in several different outcomes in RNA encapsidation. In addition, mutant with specific arginines changed to lysines in the capsid also exhibited defects in the specific encapsidation of one or more of the four BMV positive-strand RNAs. The experimental results indicate that electrostatics is a major component in RNA encapsidation, but was unable to account for all of the observed effects on RNA encapsidation. Thermodynamic modeling incorporating the electrostatics was able to predict the approximate length of the RNA to be encapsidated for the majority of mutant virions, but not for a mutant with extreme clustered positive charges. Cryo-electron microscopy of virions that encapsidated an additional copy of RNA4 revealed that, despite the increase in RNA encapsidated, the capsid structure was minimally changed. These results experimentally demonstrated the impact of electrostatics and additional restraints in the encapsidation of BMV RNAs, which could be applicable to other viruses.
doi:10.1016/j.jmb.2012.03.023
PMCID: PMC3360812  PMID: 22472420
Brome Mosaic Virus; coat protein; capsid; RNA encapsidation; electrostatic interaction; thermodynamic modeling; virions; cryo-EM
19.  Expression of SET Protein in the Ovaries of Patients with Polycystic Ovary Syndrome 
Background. We previously found that expression of SET gene was up-regulated in polycystic ovaries by using microarray. It suggested that SET may be an attractive candidate regulator involved in the pathophysiology of polycystic ovary syndrome (PCOS). In this study, expression and cellular localization of SET protein were investigated in human polycystic and normal ovaries. Method. Ovarian tissues, six normal ovaries and six polycystic ovaries, were collected during transsexual operation and surgical treatment with the signed consent form. The cellular localization of SET protein was observed by immunohistochemistry. The expression levels of SET protein were analyzed by Western Blot. Result. SET protein was expressed predominantly in the theca cells and oocytes of human ovarian follicles in both PCOS ovarian tissues and normal ovarian tissues. The level of SET protein expression in polycystic ovaries was triple higher than that in normal ovaries (P < 0.05). Conclusion. SET was overexpressed in polycystic ovaries more than that in normal ovaries. Combined with its localization in theca cells, SET may participate in regulating ovarian androgen biosynthesis and the pathophysiology of hyperandrogenism in PCOS.
doi:10.1155/2013/367956
PMCID: PMC3686144  PMID: 23861679
20.  CYP2C19 Phenotype, Stent Thrombosis, Myocardial Infarction, and Mortality in Patients with Coronary Stent Placement in a Chinese Population 
PLoS ONE  2013;8(3):e59344.
Background
Several studies have indicated that CYP2C19 loss-of-function polymorphisms have a higher risk of stent thrombosis (ST) after percutaneous coronary interventions (PCIs). However, this association has not been investigated thoroughly in a Chinese population. In this study, we aimed to determine the effect of CYP2C19*2 and CYP2C19*3 loss-of-function polymorphisms on the occurrence of ST and other adverse clinical events in a Chinese population.
Methods
We designed a cohort study among 1068 consecutive patients undergoing intracoronary stent implantation after preloading with 600 mg of clopidogrel. CYP2C19*2 and CYP2C19*3 were genotyped by using polymerase chain reaction-restriction fragment length polymorphism analysis. The adverse clinical events recorded were ST, death, myocardial infarction (MI), and bleeding events. The primary end point of the study was the incidence of cumulative ST within 1 year after PCI. The secondary end point was other adverse clinical outcomes 1 year after the procedure.
Results
The cumulative 1-year incidence of ST was 0.88% in patients with extensive metabolizers (EMs) (CYP2C19*1/*1 genotype), 4.67% in patients with intermediate metabolizers (IMs) (CYP2C19*1/*2 or *1/*3 genotype), and 10.0% in patients with poor metabolizers (PMs) (CYP2C19*2/*2, *2/*3, or *3/*3 genotype) (P<0.001). The one-year event-free survival was 97.8% in patients with EMs, 96.5% in patients with IMs, and 92.0% in patients with PMs (P = 0.014). Multivariate analysis confirmed the independent association of CYP2C19 loss-of-function allele carriage with ST (P = 0.009) and total mortality (P<0.05).
Conclusion
PM patients had an increased risk of ST, death, and MI after coronary stent placement in a Chinese population.
doi:10.1371/journal.pone.0059344
PMCID: PMC3595238  PMID: 23555019
21.  SET protein up-regulated testosterone production in the cultured preantral follicles 
Background
We found previously that the expression of SET gene was up-regulated in polycystic ovaries. Evidences suggested that SET protein was essential for regulating both the promoter activity of CYP17A1 and the biological activity of P450c17. In this study, we explored whether SET regulated androgen production in preantral follicles.
Methods
The mouse preantral follicles were cultured in vitro. Testosterone secretion and expression of steroidogenic enzymes were observed in the preantral follicles treated in vitro by SET overexpression and knockdown.
Results
Testosterone levels in the media of the AdCMV-SET infected follicles significantly increased, and the CYP17A1 and HSD3B2 expression also significantly increased (P < 0.05). Testosterone levels in AdSiRNA-SET infected group decreased, and so did CYP17A1 and HSD3B2 expression (P < 0.05).
Conclusions
SET played a positive role in regulating ovarian androgen biosynthesis by enhancing the transcription of steroidogenic enzymes CYP17A1 and HSD3B2, which maybe contribute to the hyperandrogenism in PCOS.
doi:10.1186/1477-7827-11-9
PMCID: PMC3583798  PMID: 23421880
SET; Androgen production; Preantral follicles
22.  Thermal hysteresis in the backbone and side chain dynamics of the elastin mimetic peptide [VPGVG]3 revealed by 2H NMR 
We report on experimental measurements of the backbone and side chain dynamics of the elastin mimetic peptide [VPGVG]3 by 2H NMR echo spectroscopy and 2D T1-T2 correlation relaxometry. The T1 and T2 relaxation times of the Gly α-deuterons and Val α-, β- and γ- deuterons of a hydrated sample reveal a thermal hysteresis when the temperature is raised from −10°C to 45°C and then subsequently cooled back to −10°C. In addition, near 30°C we observe a reduction in the slope of the T1(T) and T2(T) heating curves, indicating a structural change that appears to be correlated well to the known inverse temperature transition of this peptide. The thermal dependence of the correlation times of the Gly α-deuterons are well fit by an Arrhenius Law, from which we have measured Eact =(20.0 ± 3.1) kJ/mol when the sample is heated, and Eact =(10.9 ± 2.8) kJ/mol when cooled. Molecular dynamics simulations support the notion that the measured activation energy is determined largely by the extent of localized water, which is observed to decrease with increasing temperature from approximately 25°C to 42°C.
doi:10.1021/jp208966k
PMCID: PMC3257400  PMID: 22142235
23.  Personalised modified osteotomy using computer-aided design–rapid prototyping to correct thoracic deformities 
International Orthopaedics  2010;35(12):1827-1832.
The correction of severe thoracic deformities is challenging. However, the usual imaging modalities are not sufficient for performing the surgery. Our objective was to describe the procedure and results of posterior modified wedge osteotomy aided by the techniques of computer-aided design–rapid prototyping (CAD-RP) to correct thoracic deformities. Twenty-one patients with thoracic deformities (eight males; 13 females) formed the study group. All patients underwent computed tomography (CT) scanning and CAD-RP, and a model of thoracic deformities and navigation templates of pedicles were created for each patient and used to analyse the spinal deformities and serve as anatomical reference. Aided by these models, personalised modified wedge osteotomy combining the eggshell technique and posterior vertebral column resection was performed. Using CAD-RP improved the safety and accuracy of surgery and screw placement in the 21 patients in whom 41 vertebrae were removed and 216 pedicle screws were placed. The average operation time was 260 (200–420) min, with an average blood loss of 1,900 ml (range 800–3560 ml). The percentage of deformity correction was 56.3% (from 72.1° to 31.5°) in the coronal plane and 60.4% (from 81.6° to 32.3°) in the sagittal plane. No patient had serious complications or implant failure. Personalised single-stage posterior modified wedge osteotomy is an effective procedure for treating thoracic deformities. Using CAD-RP and the RP models have significant benefits for personalised surgical treatment of complex thoracic deformities.
doi:10.1007/s00264-010-1155-9
PMCID: PMC3224619  PMID: 21125271
24.  Molecular characteristics of erythromycin-resistant Streptococcus pneumoniae from pediatric patients younger than five years in Beijing, 2010 
BMC Microbiology  2012;12:228.
Background
Streptococcus pneumoniae is the main pathogen that causes respiratory infections in children younger than five years. The increasing incidence of macrolide- and tetracycline-resistant pneumococci among children has been a serious problem in China for many years. The molecular characteristics of erythromycin-resistant pneumococcal isolates that were collected from pediatric patients younger than five years in Beijing in 2010 were analyzed in this study.
Results
A total of 140 pneumococcal isolates were collected. The resistance rates of all isolates to erythromycin and tetracycline were 96.4% and 79.3%, respectively. Of the 135 erythromycin-resistant pneumococci, 91.1% were non-susceptible to tetracycline. In addition, 30.4% of the erythromycin-resistant isolates expressed both the ermB and mef genes, whereas 69.6% expressed the ermB gene but not the mef gene. Up to 98.5% of the resistant isolates exhibited the cMLSB phenotype, and Tn6002 was the most common transposon present in approximately 56.3% of the resistant isolates, followed by Tn2010, with a proportion of 28.9%. The dominant sequence types (STs) in all erythromycin-resistant S. pneumoniae were ST271 (11.9%), ST81 (8.9%), ST876 (8.9%), and ST320 (6.7%), whereas the prevailing serotypes were 19F (19.3%), 23F (9.6%), 14 (9.6%), 15 (8.9%), and 6A (7.4%). The 7-valent pneumococcal conjugate vaccine (PCV7) and 13-valent pneumococcal conjugate vaccine (PCV13) coverage of the erythromycin-resistant pneumococci among the children younger than five years were 45.2% and 62.2%, respectively. ST320 and serotype 19A pneumococci were common in children aged 0 to 2 years. CC271 was the most frequent clonal complex (CC), which accounts for 24.4% of all erythromycin-resistant isolates.
Conclusions
The non-invasive S. pneumoniae in children younger than five years in Beijing presented high and significant resistance rates to erythromycin and tetracycline. The expressions of ermB and tetM genes were the main factors that influence pneumococcal resistance to erythromycin and tetracycline, respectively. Majority of the erythromycin-resistant non-invasive isolates exhibited the cMLSB phenotype and carried the ermB, tetM, xis, and int genes, suggesting the spread of the transposons of the Tn916 family. PCV13 provided higher serotype coverage in the childhood pneumococcal diseases caused by the erythromycin-resistant isolates better than PCV7. Further long-term surveys are required to monitor the molecular characteristics of the erythromycin-resistant S. pneumoniae in children.
doi:10.1186/1471-2180-12-228
PMCID: PMC3534231  PMID: 23043378
25.  Expression Trend of Selected Ribosomal Protein Genes in Nasopharyngeal Carcinoma 
Background:
Ribosomal proteins are traditionally associated with protein biosynthesis until recent studies that implicated their extraribosomal functions in human diseases and cancers. Our previous studies using GeneFishing™ DEG method and microarray revealed underexpression of three ribosomal protein genes, RPS26, RPS27, and RPL32 in cancer of the nasopharynx. Herein, we investigated the expression pattern and nucleotide sequence integrity of these genes in nasopharyngeal carcinoma to further delineate their involvement in tumourigenesis. The relationship of expression level with clinicopathologic factors was also statistically studied.
Methods:
Quantitative Polymerase Chain Reaction was performed on nasopharyngeal carcinoma and their paired normal tissues. Expression and sequence of these three genes were analysed.
Results:
All three ribosomal protein genes showed no significant difference in transcript expressions and no association could be established with clinicopathologic factors studied. No nucleotide aberrancy was detected in the coding regions of these genes.
Conclusion:
There is no early evidence to substantiate possible involvement of RPS26, RPS27, and RPL32 genes in NPC tumourigenesis.
PMCID: PMC3629677  PMID: 23613646
NPC; RP; RPS27; RPS26; RPL32; transcript expression

Results 1-25 (46)