Mufei Li

The Association of Sport Performance with ACE and ACTN3 Genetic Polymorphisms: A Systematic Review and Meta-Analysis

Background Genetic polymorphism is suggested to be associated with human physical performance. The angiotensin I-converting enzyme insertion/deletion (ACE I/D) polymorphism and the α-actinin-3 gene (ACTN3) R577X polymorphism have been most widely studied for such association analysis. However, the findings are frequently heterogeneous. We aim to summarize the associations of ACE I/D and ACTN3 R577X with sport performance by means of meta-analysis. Methods We systematically reviewed and quantitatively summarized published studies, until October 31, 2012, on relationship between ACE/ACTN3 genetic polymorphisms and sports performance, respectively. Results A total of 366 articles on ACE and 88 articles on ACTN3 were achieved by literature search. A significant association was found for ACE II genotype compared to D allele carriage (DD+ID) with increased possibility of physical performance (OR, 1.23; 95% CI, 1.05–1.45). With respect to sport discipline, the II genotype was found to be associated with performance in endurance athletes (OR, 1.35; 95% CI, 1.17–1.55). On the other hand, no significant association was observed for ACTN3 RR genotype as compared to X allele carriage (XX+RX) (OR, 1.03; 95% CI, 0.92–1.15). However, when restricted the analyses to power events, a significant association was observed (OR, 1.21; 95% CI, 1.03–1.42). Conclusion Our results provide more solid evidence for the associations between ACE II genotype and endurance events and between ACTN3 R allele and power events. The findings suggest that the genetic profiles might influence human physical performance.

Human Papillomavirus Infection and Laryngeal Cancer Risk: A systematic review and meta-analysis

BACKGROUND A number of molecular epidemiological studies have been conducted to explore the association of human papillomavirus (HPV) infection with laryngeal cancer. However, the findings are heterogeneous. METHODS We systematically reviewed studies on HPV infection and laryngeal cancer published up to 15 May 2012 and quantitatively summarized the prevalence of HPV infection and its association with the risk of laryngeal cancer by means of meta-analysis. RESULTS In total, 55 eligible studies were included. The overall HPV prevalence in laryngeal cancer tissues was 28.0% (95% confidence interval [CI], 23.5%-32.9%). A total of 26.6% laryngeal cancer patients were infected with high-risk HPV types only, and HPV-16 was most frequently observed type, with a prevalence of 19.8% (95% CI, 15.7%-24.6%). The meta-analysis based on 12 eligible case-control studies suggests a strong association between HPV infection and laryngeal squamous cell carcinoma, with a summary odds ratio (OR) of 5.39 (95% CI, 3.25-8.94). Different magnitudes of association were observed for HPV-16 (OR, 6.07; 95% CI, 3.44-10.70) and HPV-18 (OR = 4.16; 95% CI, .87-20.04; P < .01). Stratified analyses were performed with respect to HPV genotypes and characteristics of the study population. CONCLUSIONS HPV infection, especially infection due to the high-risk type HPV-16, was found to be significantly associated with the risk of laryngeal squamous cell carcinoma.

Latent tuberculosis infection in rural China: baseline results of a population-based, multicentre, prospective cohort study

BACKGROUND Prophylactic treatment of individuals with latent Mycobacterium tuberculosis infection is an essential component of tuberculosis control in some settings. In China, the prevalence of latent tuberculosis infection, and preventive interventions against this disease, have not been systematically studied. We aimed to assess the prevalence of latent tuberculosis and its associated risk factors in rural populations in China. METHODS Between July 1, and Sept 30, 2013, we undertook a baseline survey of a population-based, multicentre, prospective cohort study of registered residents (≥5 years old) at four study sites in rural China. Eligible participants were identified by door-to-door survey with a household sampling design. We screened participants for active tuberculosis and history of tuberculosis then used a tuberculin skin test and an interferon-γ release assay (QuantiFERON [QFT]) to test for latent infection. We used odds ratios (ORs) and 95% CIs to assess variables associated with positivity of QFT and tuberculin skin tests. FINDINGS 21,022 (90%) of 23,483 eligible participants completed a baseline survey. Age-standardised and sex-standardised rates of skin-test positivity (≥10 mm) ranged from 15% to 42%, and QFT positivity rates ranged from 13% to 20%. Rates of positivity for the tuberculin skin test and the QFT test were low in study participants younger than 20 years and gradually increased with age (p for trend <0·0001). Rates of latent tuberculosis infection were higher for men than women (p<0·0001). Overall agreement between the tuberculin skin test and the QFT test was moderate (81·06%; kappa coefficient 0·485), with skin-test-only positive results associated with the presence of BCG scar, male sex, and ages of 60 years and older, and QFT-only positive results associated with male sex and ages of 60 years and older. INTERPRETATION On the basis of findings showing that the performance of the tuberculin skin test might be affected by various factors including BCG vaccination and age, our results suggest that the prevalence of latent tuberculosis in China might be overestimated by skin tests compared with interferon-γ release assays. FUNDING The National Science and Technology Major Project of China, the Program for Changjiang Scholars and Innovative Research Team in University of China.

Systematic review with meta-analysis: the association between human papillomavirus infection and oesophageal cancer

Human papillomavirus (HPV) infection might be one of the potential risk factors for oesophageal cancer. However, the previous epidemiological findings were heterogeneous.

Association of human papillomavirus infection and abnormal anal cytology among HIV-infected MSM in Beijing, China.

Background In the recent years, dramatic increases in HIV transmission among men who have sex with men (MSM) have been observed in China. Human papillomavirus (HPV) infection related anal cancer is more common among HIV-infected MSM as compared to the general population. However, HPV infection and anal cytology has been rarely studied in HIV-infected MSM in China. Methods HIV-infected MSM in Beijing, China were invited to participate in this study between January and April 2011. Anal swabs were collected for examining cytology and HPV genotypes. Results Ninety-five eligible participants with complete questionnaire and laboratory data were included in the analyses. Thirty six of them (37.9%) showed abnormal anal cytology as follows: atypical squamous cells of undetermined significance (ASC-US) in 19 (20.0%), atypical squamous cells but cannot exclude HSIL (ASC-H) in 1 (1.1%), low-grade squamous intraepithelial lesion (LSIL) in 15 (15.8%), and high-grade squamous intraepithelial lesion (HSIL) in 1 (1.1%). HPV6 (20.0%), HPV16 (10.9%), HPV56 (10.9%), HPV52 (9.1%) and HPV39 (9.1%) were observed most frequently among those with normal anal cytology, while different distribution was found in the ones with abnormal anal cytology as HPV6 (19.4%), HPV16 (19.4%), HPV45 (16.7%), HPV52 (16.7%) and HPV18 (11.1%). In addition, HPV16, HPV45, HPV52 and HPV18 were the most frequent high-risk types in patients with abnormal anal cytology. HPV multiplicity was found to be significantly related to the prevalence of abnormal anal cytology (p for trend = 0.04). Conclusions High prevalence of HPV infection and abnormal anal cytology was observed among HIV-infected MSM in China. Infection of multiple HPV types or high-risk types was found to be associated with an increased risk of abnormal anal cytology.

Potential association of pulmonary tuberculosis with genetic polymorphisms of toll-like receptor 9 and interferon-gamma in a Chinese population

BackgroundAssociation studies have been employed to investigate the relationships between host single nucleotide polymorphisms (SNPs) and susceptibility to pulmonary Tuberculosis (PTB). However, such candidate genetic markers have not been widely studied in Chinese population, especially with respect to the disease development from latent M. tuberculosis infection (LTBI).MethodsIn this case–control study, 44 candidate SNPs were examined in a total of 600 participants (PTB patients, LTBI controls and healthy controls without M. tuberculosis infection) from Zhengzhou, China. The two groups of controls were frequency matched on gender and age with PTB patients. Genotyping was carried out by the Illumina Golden Gate assay.ResultsWhen comparing PTB patients with LTBI controls but not healthy controls without M. tuberculosis infection, significant associations with disease development were observed for TLR9 1174 A/G, TLR9 1635 A/G and IFNG 2109G/A. The two loci in TLR9 were in LD in our study population (r2=0.96, D’=1.00). A combined effect of the genotypes associated with increased risk of PTB (i.e. TLR9 1174G/G and IFNG 2109 A/A) was found when comparing PTB patients with LTBI controls (p=0.004) but not with healthy controls without infection (p=0.433).ConclusionsPotential associations between TLR9 and IFN-γ genetic polymorphisms and PTB were observed in a Chinese population which supports further study of the roles played by TLR9/IFN-γ pathway during the development of PTB.

Annual risk of tuberculosis infection in rural China: a population-based prospective study

Prospective population data on the incidence of tuberculosis (TB) infection has been sparsely reported in the global literature. A population-based prospective study was conducted in rural China to investigate the annual risk of TB infection, and its persistence using serial tuberculin skin tests (TSTs) and an interferon-γ release assay. In total, 13 580 eligible participants from four rural sites, identified as TST negative (<10 mm) or QuantiFERON-TB Gold In-Tube (QFT) (an interferon-γ release assay) negative from a baseline survey, were included in the first years follow-up examination. The annual conversion rate of QFT among the study sites ranged between 2.1% and 4.9% (average 3.1%), and the incidence of TST conversion ranged between 6.0% and 31.1% (average 14.5%). During the second years follow-up, infection persistence was investigated using 390 subjects with QFT conversions. Among them, 49.7% (164 out of 330) were found to be consistently QFT positive. Both the conversion and the persistence of QFT positivity were found to be significantly increased with increasing age. In conclusion, the annual TB infection rate was suggested to be ∼1.5% based on persistent positive results after QFT conversion in rural China. Therefore, infection control among those high-risk populations, including the elderly, should be prioritised for TB control in China. Annual TB infection rate ∼1.5% in rural China, based on persistent positive results after IGRA conversion http://ow.ly/4n95Cw

Anal HPV/HIV co-infection among Men Who Have Sex with Men: a cross-sectional survey from three cities in China.

Anal human papillomavirus (HPV) infection, which is linked to anal warts and anal cancer, is common among men who have sex with men (MSM), especially among those HIV positives. MSM aged 18 years or older were recruited from mainland China. Blood and anal cytologic samples were collected for HIV-1 serological test and HPV genotyping. A total of 889 eligible participations were included. The genotyping results of HPV were available for 822 participants (92.46%), 65.32% of which were positive for the targeted 37 HPV types. Prevalence of infection with any type of HPV was higher among HIV-infected participants (82.69%) as compared to HIV-uninfected participants (62.81%) (p < 0.01). HPV06 (15.45%), HPV18(13.50%), HPV16 (11.44%), and HPV11 (10.71%) were the most frequent types identified in the study population. Ever had paid sex with man was found to be independent predictor for HPV positivity with an adjusted odds ratios (OR) of 2.34 (1.16–4.74). Anal HPV positivity was observed to be independently associated with HIV infection with an adjusted OR of 3.03 (1.76–5.21) in the study population. In conclusion, the prevalence of anal HPV infection was observed to be common among MSM from mainland China, and it was significantly associated with the status of HIV infection.

Anal Human Papillomavirus Genotyping among HIV-Positive Men Who Have Sex with Men in Xi'an, China.

Background Anal human papillomavirus (HPV) infection and its related diseases are relatively common in men who have sex with men (MSM), especially in those HIV positive. In China, molecular epidemiology of anal HPV infection among HIV-positive MSM has been sparsely studied. Methods A cross-sectional study was conducted among HIV-positive MSM in Xi’an, China between April and July 2014. Anal swabs were collected for HPV genotyping. Results A total of 195 HIV-positive MSM were included in this study. HPV genotyping showed that 99.0% (191/193) of participants were positive for at least one of the targeted 37 HPV genotypes. 183 (94.8%) of them were infected with multiple high-risk types and 154 (79.8%) of them with low-risk HPV types. HPV 18 was the most frequently identified high-risk type, followed by HPV 16 and HPV 51. As for low-risk types, HPV11, HPV 6 and HPV 81 were most commonly observe. High-risk HPV infection was found to be associated with the status of antiretroviral therapy (ART), the distribution of low-risk types was observed to be varied by CD4+ T cell level. Conclusion Almost all HIV-positive MSM were anal HPV infected in our study. It is highly recommended to consider regular active screening and preventive intervention of HPV infection among this high risk population.

Fast formation and growth of high-density Sn whiskers in Mg/Sn-based solder/Mg joints by ultrasonic-assisted soldering: Phenomena, mechanism and prevention

A universally applicable method for promoting the fast formation and growth of high-density Sn whiskers on solders was developed by fabricating Mg/Sn-based solder/Mg joints using ultrasonic-assisted soldering at 250 °C for 6 s and then subjected to thermal aging at 25 °C for 7 d. The results showed that the use of the ultrasonic-assisted soldering could produce the supersaturated dissolution of Mg in the liquid Sn and lead to the existence of two forms of Mg in Sn after solidification. Moreover, the formation and growth of the high-density whiskers were facilitated by the specific contributions of both of the Mg forms in the solid Sn. Specifically, interstitial Mg can provide the persistent driving force for Sn whisker growth, whereas the Mg2Sn phase can increase the formation probability of Sn whiskers. In addition, we presented that the formation and growth of Sn whiskers in the Sn-based solders can be significantly restricted by a small amount of Zn addition (≥3 wt.%), and the prevention mechanisms are attributed to the segregation of Zn atoms at grain or phase boundaries and the formation of the lamellar-type Zn-rich structures in the solder.