Previous studies suggested a rapid increase of HIV prevalence among MSM in China in recent years, from 0.4% in 2004 to 5.8% in 2008. However, some MSM had never been tested for HIV. In order to expand the accessibility to HIV testing, understanding HIV testing behavior and barriers among MSM is important. Using data collected from 307 young migrant MSM (aged 18-29 years) in 2009 in Beijing, we aimed to identify psychological and structural barriers to HIV testing. MSM were recruited through peer outreach, informal social networks, internet outreach, and venue-based outreach. Participants completed a confidential self-administered questionnaire.Results show that about 72% of MSM had ever had HIV testing. Logistic regression analysis indicated that the HIV testing behavior was associated with sexual risk behaviors (e.g., multiple sexual partners, inconsistent condom use for anal sex) and history of STDs. Eighty four MSM (28%) who had never had HIV testing reported that the psychological barriers mainly were perceived low risk of HIV infection and fears of being stigmatized. The structural barriers reported included inconvenience of doing test and lack of confidentiality. Future HIV prevention programs should be strengthened among MSM to increase their awareness of HIV risk. Efforts are needed to increase access to quality and confidential HIV testing among MSM and reduce stigma against MSM.

We demonstrated a compact and highly-sensitive curvature sensor based on a Mach-Zehnder interferometer created in a photonic crystal fiber. Such a Mach-Zehnder interferometer consisted of a peanut-like section and an abrupt taper achieved by use of an optimized electrical arc discharge technique, where only one dominating cladding mode was excited and interfered with the fundamental mode. The unique structure exhibited a high curvature sensitivity of 50.5 nm/m^-1 within a range from 0 to 2.8 m^-1, which made it suitable for high-sensitivity curvature sensing in harsh environments. Moreover, it also exhibited a temperature sensitivity of 11.7 pm/°C.

The purpose of the study is to explore the disclosure of same-sex behavior by men who have sex with men (MSM) to different groups of people (i.e. family, friends, coworkers, and doctors) and the associated sociodemographic, behavioral, and psychosocial factors. A self-administered survey was conducted among 307 migrant MSM, aged 18-30, in Beijing in 2009. Most MSM disclosed their same-sex behavior to friends (69%), followed by family (25%), coworkers (25%), and doctors (24%). Factors associated with disclosure to friends included higher levels of perceived stigma, social capital and acculturation in Beijing, and suspecting partner to have a sexually transmitted disease (STD). Factors associated with disclosure to family included lower levels of internalized stigma, higher levels of acculturation in Beijing, and both risk and protective behavioral factors. MSM who disclosed to coworkers reported having worked in more cities, living with coworkers, and lower levels of social capital in Beijing. Disclosure to doctors was related to STD infection, sex partner, and sociodemographic factors. Results indicated that selective disclosure by MSM was situational and context-based. Future HIV/STD intervention needs to take into account factors relevant to their selective disclosure to different audiences.

Trientine (TETA), a copper (Cu) chelator, is capable of replenishing Cu in the heart, and Cu repletion reduces cardiac fibrosis in a rodent model of cardiac hypertrophy. This study was undertaken to explore possible mechanisms by which Cu repletion diminishes cardiac fibrosis. Adult male Sprague-Dawley rats were subjected to ascending aortic constriction to induce cardiac hypertrophy. Four months after the operation, cardiac hypertrophy along with fibrosis was fully developed. TETA treatment was then followed at a dose of 21.9 mg kg, twice a day, administered orally for six weeks. At the end of the treatment, the hearts were harvested and all of the tissue samples were subjected to qRT-PCR, western blot, Sirius red staining, hydroxyproline assay, and immunostaining analyses. TETA treatment significantly increased the content of Cu in the hypertrophied myocardium, decreased type III collagen deposition and reduced cardiac fibrosis. On the other hand, this treatment did not alter the increase in fibroblasts induced by pressure overload, but significantly increased matrix metalloproteinase-2 (MMP-2), which is the enzyme mainly responsible for degradation of collagens in the heart. In addition, the mRNA and protein levels of tissue inhibitors of matrix metalloproteinase-1 and -2 (TIMP-1 and TIMP-2) were both remarkably increased in the hypertrophic myocardium, and normalized after TETA treatment. The data thus demonstrated that the reduction in cardiac fibrosis by TETA-induced Cu repletion is associated at least in part with an enhanced MMP-2 activity, leading to collagen degradation.

Myocardial fibrogenesis is initiated once the coordination between oxygen supply and demand is disrupted in pressure overload-induced cardiac hypertrophy. Clinical observations showed that myocardial fibrosis did not evenly occur in the hypertrophic myocardium. The present study was undertaken to specifically address differential vulnerabilities to fibrogenesis of different regions in the myocardium subjected to pressure overload-induced hypertrophy. SD rats were divided into two groups, sham-operated control and ascending artery constriction-induced cardiac hypotrophy. Thirty-four weeks after surgery, rats were sacrificed and hearts were harvested. Myocardial tissues were processed and sequentially sectioned for detection of collagen deposition, myocyte hypertrophy and vascular density analysis. Redundant collagen stained with Sirius red and anti-collagen I antibody was found in the extracellular matrix, but high volume of collagen fraction was largely localized more in posterior and lateral walls than in anterior wall and interventricular septum, which is in accordance with the accumulation of fibroblasts. In association with the differential regional collagen accumulation, the cardiomyocytes were more hypertrophic in the posterior and lateral wall than the other left ventricle. However, the capillary density in the lateral and posterior walls was significantly decreased. The results indicated that the posterior and lateral walls were more vulnerable to fibrogenesis post-pressure overload-induced cardiac hypertrophy, which was associated with the depressed angiogenesis in these two regions.