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Cdc42 is a Ras-related small GTP-binding protein. A previous study has shown that Cdc42 binding to the ? subunit of the coatomer protein complex (?COP) is essential for Cdc42-regulated cellular transformation, but the molecular mechanism involved is not well understood. Here, we demonstrate that constitutively-active Cdc42 binding to ?COP induced the accumulation of epithelial growth factor receptor (EGFR) in the cells, sustained EGF-stimulated extracellular signal-regulated kinase (ERK), JUN amino-terminal kinase (JNK) and phosphoinositide 3-kinase (PI3K) signaling and promoted cell division. Moreover, constitutive Cdc42 activity facilitated the nuclear translocation of EGFR, and this indicates a novel mechanism through which Cdc42 might promote cellular transformation. [ABSTRACT FROM AUTHOR]

Background Increasing incidence rates of thyroid cancer have been noted worldwide, while the underlying reasons remain unclear. Methods Using data from population-based cancer registries, we examined the time trends of thyroid cancer incidence in two largest cities in China, Shanghai and Hong Kong, during the periods 1973-2009 and 1983-2011, respectively. We further performed age-period-cohort analyses to address the possible underlying reasons for the observed temporal trends. Results We observed continuous increases in the incidence rates of thyroid cancer in Shanghai and Hong Kong, since the 1980s, in addition to higher incidence rates in the 1970s in both sexes in Shanghai. The age-standardized incidence rate of thyroid cancer increased by 3.1% [95% confidence interval (CI): 1.0%, 5.1%] and 3.8% (95% CI: 1.9%, 5.7%) per year on average, respectively, in Shanghai men and women during the period 1973-2009, while it increased by 2.2% (95% CI: 1.5%, 2.8%) and 2.7% (1.6%, 3.8%) per year on average, respectively, in Hong Kong men and women during the period 1983-2011. We observed global changes in trends across all age groups in similar ways, in addition to varied trends across different generations (birth cohorts). Conclusions The increased incidence rates of thyroid cancer in these two Chinese populations during recent decades may be contributable to a combination of the introduction of more sensitive diagnostic techniques and the increasing prevalence of environmental exposures in the populations. [ABSTRACT FROM AUTHOR]

Different risks of HIV infection have been reported among different types of male sex workers (MSW). In order to compare the prevalence of HIV infection and related risk behaviors of MSW in different venues in Shenzhen, China, a time-location sampling survey was conducted in 2008. 5.1% of the 394 MSWs were tested positive for HIV, with 6.9% in those working in parks (PMSW), 11.3% in small family clubs (FMSW) and 1.7% in entertainment venues. PMSWs and FMSWs reported a higher proportion of self-identified homosexual/gay. Moreover, FMSWs reported a lower coverage of HIV-related education and services and were more likely to self-report coming from provinces with higher HIV prevalence. The results indicated that MSWs in small venues and parks were comparatively at higher risk of being infected and suggested that current HIV preventive intervention needs to be expanded to the small venues in Shenzhen. [ABSTRACT FROM AUTHOR]

Background: MiR-221 and miR-222 (miR-221/222) are frequently up-regulated in various types of human malignancy including glioblastoma. Recent studies have reported that miR-221/222 regulate cell growth and cell cycle progression by targeting p27 and p57. However the underlying mechanism involved in cell survival modulation of miR-221/222 remains elusive. Results: Here we showed that miR-221/222 inhibited cell apoptosis by targeting pro-apoptotic gene PUMA in human glioma cells. Enforced expression of miR-22/222 induced cell survival whereas knockdown of miR-221/222 rendered cells to apoptosis. Further, miR-221/222 reduced PUMA protein levels by targeting PUMA-3'UTR. Introducing PUMA cDNA without 3'UTR abrogated miR-221/222-induced cell survival. Notably, knockdown of miR- 221/222 induces PUMA expression and cell apoptosis and considerably decreases tumor growth in xenograft model. Finally, there was an inverse relationship between PUMA and miR-221/222 expression in glioma tissues. Conclusion: To our knowledge, these data indicate for the first time that miR-221/222 directly regulate apoptosis by targeting PUMA in glioblastoma and that miR-221/222 could be potential therapeutic targets for glioblastoma intervention. [ABSTRACT FROM AUTHOR]

Male sex workers serving Hong Kong male clients in Shenzhen were surveyed ( n = 199); 98.9% had been in Shenzhen for ≤3 years; 83.4% served local male clients; 82.8% had no family members/relatives in Shenzhen; 58.3% depended exclusively on sex work; 73% were bothered by one’s sex work; and 81.7% found financial support unavailable when needed. About 29.1% had had unprotected anal intercourse (UAI) with Hong Kong male clients in the last month. UAI behavior was associated with exposure to HIV prevention services (OR = 0.08) and poor social support, being bothered by the sex work, substance use, and type of sex work venue (OR = 2.92–5.96). [ABSTRACT FROM AUTHOR]

Abstract   Culex pipiens pallens is the mosquito vector of a number of human pathogens such as Wuchereria bancrofti, Brugia malayi, and epidemic encephalitis B virus. Female C. pipiens pallens play an important role in transmitting pathogens by sucking blood, which is essential for reproduction. In the present study, a subtractive cDNA library for female C. pipiens pallens was constructed by the suppression subtractive hybridization (SSH) technique and then 100 clones from the female SSH library were sequenced and analyzed. Female-differentially expressed genes in C. pipiens pallens were screened using semiquantitative RT-PCR. The full-length cDNA of an EST sequence (fs68) that was specifically expressed in female C. pipiens pallens was characterized by 3′ and 5′ rapid amplification of cDNA ends (RACE). The characteristics of the female-specific gene were further analyzed using bioinformatics and Northern blot. It was shown that the female-specific gene was a previously uncharacterized gene and may encode a salivary peptide. This putative salivary peptide could be a very important molecule in the blood feeding of female C. pipiens pallens. [ABSTRACT FROM AUTHOR]

Objective: To screen and evaluate the active constituents of Chinese medicinal herbs as potent inhibitors of Cdc25 phosphatase. Methods: The affinity chromatography purified glutashione-S-transferase/Cdc25A phosphatase fusion protein and Cdc2/cyclin B from the extracts of starfish M phase oocytes are used as the cell cycle-specific targets for screening the antimitotic constituents. We tested 9 extracts isolated from the Chinese medicinal herbs and vegetables including the agents currently used in cancer treatment by measuring the inhibition of Cdc25A phosphatase and Cdc2 kinase activity. The antitumor activity of the extracts was also evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and flow cytometry. Results: Cdc25A inhibitory activity and antitumor activity are detected in the extracts isolated from three Chinese medicinal herbs Agrimona pilosa; Herba solani lyrati; Galla chinesis. Conclusion: We found three extracts isolated from Chinese medicinal herbs have potential inhibitory activity of Cdc25 phosphatase using a highly specific mechanism-based screen assay for antimitotic drug discovery. [ABSTRACT FROM AUTHOR]

Background: HIV transmission among men who have sex with men has recently become a major concern in China. Little is known, however, about HIV transmission among male sex workers (MSW). This study aimed to investigate HIV infection prevalence and risk factors among MSW in Shenzhen, China. Materials and Methods: Following formative research, a cross-sectional study was conducted using time-location sampling among MSW in Shenzhen, from April to July 2008. Behavioural and serological data on HIV and syphilis were collected. The risk factors for HIV infection were analysed using a logistic regression model. Results: In total, 394 MSW were recruited for the survey. The prevalence of HIV and syphilis among these workers was 5.3% and 14.3%, respectively. Only a quarter of the MSW self-identified as homosexual. More than 70% had sex with both men and women. HIV-related knowledge levels were high regardless of HIV serostatus. Consistent condom use was low (37.1%) and varied by type of sexual partner. Factors including more non-commercial male partners, working in small home-based family clubs, being drunk before sexual intercourse, having a history of HIV tests, syphilis infection and a short period of residence in Shenzhen were associated with an increased risk of HIV infection. Conclusions: High-risk sexual practices were common among MSW regardless of their high level of HIV awareness. The working venues were associated with HIV infection and a recent test for HIV was a potential predictor of HIV infection. The time-location sampling method was found to be an appropriate way of recruiting MSW for this study, especially those without fixed working places. [ABSTRACT FROM AUTHOR]

An abstract of the article "HIV-Related Risk Factors Among Male Sex Workers in Different Settings in Shenzhen, China," by Jin Zhao, Wen-De Cai, Lin Chen, Yong-Xia Gan, Yun-Yun Zi, Jin-Quan Cheng, Xiao-Rong Wang and Ming-Liang He is presented.

An abstract of the article "Screening of Differentially Expressed Gene in HIV/HCV Co-Infected Patients," by zhengrong Yang, Jing Zhao, Lin Chen, Jin-Quan Cheng, Ming-Liang He is presented.

RACK1 is a 7-WD motif-containing protein with numerous downstream effectors regulating various cellular functions. Using a yeast two-hybrid screen, we identified dynein light chain 1 as a novel interacting partner of RACK1. Additionally, we demonstrated that RACK1 formed a complex with DLC1 and Bim, specifically BimEL, in the presence of apoptotic agents. Upon paclitaxel treatment, RACK1, DLC1, and CIS mediated the degradation of BimEL through the ElonginB/C-Cullin2-CIS ubiquitin-protein isopeptide ligase complex. We further showed that RACK1 conferred paclitaxel resistance to breast cancer cells in vitro and in vivo. Finally, we observed an inverse correlation between CIS and BimEL levels in both ovarian and breast cancer cell lines and specimens. Our study suggests a role of RACK 1 in protecting cancer cells from apoptosis by regulating the degradation of BimEL, which together with CIS could play an important role of drug resistance in chemotherapy. [ABSTRACT FROM AUTHOR]