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Background: Arsenic is a widely distributed metalloid compound that has biphasic effects on cultured cells. In large doses, arsenic can be toxic enough to trigger cell death. In smaller amounts, non-toxic doses may promote cell proliferation and induces carcinogenesis. Aberration of chromosome is frequently detected in epithelial cells and lymphocytes of individuals from arsenic contaminated areas. Overexpression of Aurora-A, a mitotic kinase, results in chromosomal instability and cell transformation. We have reported that low concentration (≦1 μM) of arsenic treatment increases Aurora-A expression in immortalized bladder urothelial E7 cells. However, how arsenic induces carcinogenesis through Aurora-A activation remaining unclear.Methods: Bromodeoxyuridine (BrdU) staining, MTT assay, and flow cytometry assay were conducted to determine cell proliferation. Messenger RNA and protein expression levels of Aurora-A were detected by reverse transcriptional-PCR and Western blotting, respectively. Centrosome of cells was observed by immunofluorescent staining. The transcription factor of Aurora-A was investigated by promoter activity, chromosome immunoprecipitation (ChIP), and small interfering RNA (shRNA) assays. Mouse model was utilized to confirm the relationship between arsenic and Aurora-A.Results: We reveal that low dosage of arsenic treatment increased cell proliferation is associated with accumulated cell population at S phase. We also detected increased Aurora-A expression at mRNA and protein levels in immortalized bladder urothelial E7 cells exposed to low doses of arsenic. Arsenic-treated cells displayed increased multiple centrosome which is resulted from overexpressed Aurora-A. Furthermore, the transcription factor, E2F1, is responsible for Aurora-A overexpression after arsenic treatment. We further disclosed that Aurora-A expression and cell proliferation were increased in bladder and uterus tissues of the BALB/c mice after long-term arsenic (1 mg/L) exposure for 2 months.Conclusion: We reveal that low dose of arsenic induced cell proliferation is through Aurora-A overexpression, which is transcriptionally regulated by E2F1 both in vitro and in vivo. Our findings disclose a new possibility that arsenic at low concentration activates Aurora-A to induce carcinogenesis. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to propose a prognostic scoring system based on preoperative serum apolipoprotein A-1 and C-reactive protein (ApoA-1 and CRP, AC score) levels and to evaluate the prognostic value of these markers in patients with hepatocellular carcinoma (HCC).Methods: In all, 539 consecutive cases diagnosed with HCC from 2009 to 2012 at Sun Yat-sen University Cancer Center were analysed. The characteristics and levels of pretreatment lipids (ApoA-1, apolipoprotein B (Apo-B), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglycerides (TGs)) and CRP were reviewed and determined by univariate and multivariate Cox hazard models. Then, the AC score was proposed, which combines two independent risk factors (ApoA-1 and CRP).Results: The optimal cut-off points in our study were determined according to established reference ranges. Patients with decreased ApoA-1 levels (< 1.090 g/L) and increased CRP levels (≥3.00 mg/L) exhibited a significantly poor overall survival (OS) and disease-free survival (DFS). The AC score was calculated as follows: patients with decreased ApoA-1 and elevated CRP were given a score of 3, patients with only one of these abnormalities were given a score of 2, and those with no abnormalities were given a score of 1. Patients with a higher AC score showed more progressive disease and a poorer prognosis. This was observed not only in the entire cohort (for OS, P < 0.001; for DFS, P < 0.001) but also in the subgroups stratified by pathological stage (stage I-II and stage III-IV). The discriminatory ability of the AC score in HCC was assessed according to the AUC values. The AUC value of the AC score (AUC: 0.676, 95% CI: 0.629-0.723, P < 0.001) was higher than that of AFP. In addition, the combination of the AFP and AC scores (AUC: 0.700, 95% CI: 0.655-0.745, P < 0.001) was superior to the AFP and AC scores alone.Conclusions: The AC score is a significant valuable predictor of OS and DFS and could more accurately differentiate the prognosis of HCC patients. As this study is a retrospective analysis, the value of the AC score should be validated in large prospective trials. [ABSTRACT FROM AUTHOR]

Rhodococcus strains not only have been widely used in industries but also have a potential ability of producing new structural natural products. Integration of heterologous genes into chromosomes of Rhodococcus strains for gene expression can facilitate the studies and applications of these strains. A conjugation system was optimized in order to transfer enhanced green fluorescent protein (EGFP) encoding gene as a reporter from Escherichia coli into Rhodococcus erythropolis D-1. The influence of three native ribosome binding sites (RBSs) and two designed RBSs on the target protein production in R. erythropolis D-1 was also characterized. An efficient conjugation system of R. erythropolis D-1 was established to integrate EGFP gene into its chromosome. Among of five RBSs, RBS3 showed the highest translational activity in R. erythropolis D-1. [ABSTRACT FROM AUTHOR]

Background: Mutant Ras plays multiple functions in tumorigenesis including tumor formation and metastasis. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK), a metastasis inhibitor gene, suppresses matrix metalloproteinase (MMP) activity in the metastatic cascade. Clarifying the relationship between Ras and RECK and understanding the underlying molecular mechanism may lead to the development of better treatment for Ras-related tumors. Methods: Suppression subtractive hybridization PCR (SSH PCR) was conducted to identify Ha-rasval12 up-regulated genes in bladder cancer cells. Stable cell lines of human breast cancer (MCF-7-ras) and mouse NIH3T3 fibroblasts (7-4) harboring the inducible Ha-rasval12 oncogene, which could be induced by isopropylthio-β-D-galactoside (IPTG), were used to clarify the relationship between Ras and the up-regulated genes. Chromatin immunoprecipitation (ChIP) assay, DNA affinity precipitation assay (DAPA) and RECK reporter gene assay were utilized to confirm the complex formation and binding with promoters. Results: Retinoblastoma binding protein-7 (RbAp46) was identified and confirmed as a Ha-rasval12 up-regulated gene. RbAp46 could bind with histone deacetylase (HDAC1) and Sp1, followed by binding to RECK promoter at the Sp1 site resulting in repression of RECK expression. High expression of Ras protein accompanied with high RbAp46 and low RECK expression were detected in 75% (3/4) of the clinical bladder cancer tumor tissues compared to the adjacent normal parts. Ras induced RbAp46 expression increases invasion of the bladder cancer T24 cells and MMP-9 activity was increased, which was confirmed by specific lentiviral shRNAs inhibitors against Ras and RbAp46. Similarly, knockdown of RbAp46 expression in the stable NIH3T3 cells "7-4" by shRNA decreased Ras-related lung metastasis using a xenograft nude mice model. Conclusions: We confirmed that RbAp46 is a Ha-rasval12 up-regulated gene and binds with HDAC1 and Sp1. Furthermore, RbAp46 binds to the RECK promoter at the Sp1 site via recruitment by Sp1. RECK is subsequently activated, leading to increased MMP9 activity, which may lead to increased metastasis in vivo. Our findings of Ras upregulation of RbAp46 may lead to revealing a novel mechanism of Ras-related tumor cell metastasis. [ABSTRACT FROM AUTHOR]

Introduction: The effect of socioeconomic status (SES) on stroke mortality at population level has been controversial. This study explores the association of SES in childhood and adulthood with stroke mortality, as well as variations in this association among countries/regions. Methods: Sex-specific stroke mortality at country level with death registry covering ≥70% population was obtained from the World Health Organization. Human Development Index (HDI) developed by the United Nations was chosen as the SES indicator. The associations between the latest available stroke mortality with HDI in 1999 (adulthood SES) and with HDI in 1960 (childhood SES) for the group aged 45-54 years among countries were examined with regression analysis. Age-standardized stroke mortality and HDI during 1974-2001 were used to estimate the association by time point. Results: The population data were available mostly for low-middle to high income countries. HDI in 1960 and 1999 were both inversely associated with stroke mortality in the group aged 45-54 years in 39 countries/regions. HDI in 1960 accounted for 37% of variance of stroke mortality among countries/regions; HDI in 1999 for 35% in men and 53% in women (P < 0.001). There was a quadratic relationship between age-standardized stroke mortality and HDI for the countries from 1974 to 2001: the association was positive when HDI < 0.77 but it became negative when HDI > 0.80. Conclusions: SES is a strong predictor of stroke mortality at country level. Stroke mortality increased with improvement of SES in less developed countries/region, while it decreased with advancing SES in more developed areas. [ABSTRACT FROM AUTHOR]

The kidney is vulnerable to hypoxia-induced injury. One of the mechanisms underlying this phenomenon is cell apoptosis triggered by hypoxia-inducible factor-1- α (HIF-1α) activation. MicroRNA-210 (miR-210) is known to be induced by HIF-1α and can regulate various pathological processes, but its role in hypoxic kidney injury remains unclear. Here, in both rat systemic hypoxia and local kidney hypoxia models, we found miR-210 levels were upregulated significantly in injured kidney, especially in renal tubular cells. A similar increase was observed in hypoxia-treated human renal tubular HK-2 cells. We also verified that miR-210 can directly suppress HIF-1α expression by targeting the 3′ untranslated region of HIF-1α mRNA in HK-2 cells in severe hypoxia. Accordingly, miR-210 overexpression caused significant inhibition of the HIF-1α pathway and attenuated apoptosis caused by hypoxia, while miR-210 knockdown exerted the opposite effect. Taken together, our findings verify that miR-210 is involved in the molecular response in hypoxic kidney lesions in vivo and attenuates hypoxia-induced renal tubular cell apoptosis by targeting HIF-1α directly and suppressing HIF-1α pathway activation in vitro. [ABSTRACT FROM AUTHOR]

Background: Arsenic is a widely distributed metalloid compound that has biphasic effects on cultured cells. In large doses, arsenic can be toxic enough to trigger cell death. In smaller amounts, non-toxic doses may promote cell proliferation and induces carcinogenesis. Aberration of chromosome is frequently detected in epithelial cells and lymphocytes of individuals from arsenic contaminated areas. Overexpression of Aurora-A, a mitotic kinase, results in chromosomal instability and cell transformation. We have reported that low concentration (≦1 μM) of arsenic treatment increases Aurora-A expression in immortalized bladder urothelial E7 cells. However, how arsenic induces carcinogenesis through Aurora-A activation remaining unclear., Methods: Bromodeoxyuridine (BrdU) staining, MTT assay, and flow cytometry assay were conducted to determine cell proliferation. Messenger RNA and protein expression levels of Aurora-A were detected by reverse transcriptional-PCR and Western blotting, respectively. Centrosome of cells was observed by immunofluorescent staining. The transcription factor of Aurora-A was investigated by promoter activity, chromosome immunoprecipitation (ChIP), and small interfering RNA (shRNA) assays. Mouse model was utilized to confirm the relationship between arsenic and Aurora-A., Results: We reveal that low dosage of arsenic treatment increased cell proliferation is associated with accumulated cell population at S phase. We also detected increased Aurora-A expression at mRNA and protein levels in immortalized bladder urothelial E7 cells exposed to low doses of arsenic. Arsenic-treated cells displayed increased multiple centrosome which is resulted from overexpressed Aurora-A. Furthermore, the transcription factor, E2F1, is responsible for Aurora-A overexpression after arsenic treatment. We further disclosed that Aurora-A expression and cell proliferation were increased in bladder and uterus tissues of the BALB/c mice after long-term arsenic (1 mg/L) exposure for 2 months., Conclusion: We reveal that low dose of arsenic induced cell proliferation is through Aurora-A overexpression, which is transcriptionally regulated by E2F1 both in vitro and in vivo. Our findings disclose a new possibility that arsenic at low concentration activates Aurora-A to induce carcinogenesis.

Background: Mutant Ras plays multiple functions in tumorigenesis including tumor formation and metastasis. Reversion-inducing cysteine-rich protein with Kazal motifs (RECK), a metastasis inhibitor gene, suppresses matrix metalloproteinase (MMP) activity in the metastatic cascade. Clarifying the relationship between Ras and RECK and understanding the underlying molecular mechanism may lead to the development of better treatment for Ras-related tumors., Methods: Suppression subtractive hybridization PCR (SSH PCR) was conducted to identify Ha-ras (val12) up-regulated genes in bladder cancer cells. Stable cell lines of human breast cancer (MCF-7-ras) and mouse NIH3T3 fibroblasts (7-4) harboring the inducible Ha-ras (val12) oncogene, which could be induced by isopropylthio-β-D-galactoside (IPTG), were used to clarify the relationship between Ras and the up-regulated genes. Chromatin immunoprecipitation (ChIP) assay, DNA affinity precipitation assay (DAPA) and RECK reporter gene assay were utilized to confirm the complex formation and binding with promoters., Results: Retinoblastoma binding protein-7 (RbAp46) was identified and confirmed as a Ha-ras (val12) up-regulated gene. RbAp46 could bind with histone deacetylase (HDAC1) and Sp1, followed by binding to RECK promoter at the Sp1 site resulting in repression of RECK expression. High expression of Ras protein accompanied with high RbAp46 and low RECK expression were detected in 75% (3/4) of the clinical bladder cancer tumor tissues compared to the adjacent normal parts. Ras induced RbAp46 expression increases invasion of the bladder cancer T24 cells and MMP-9 activity was increased, which was confirmed by specific lentiviral shRNAs inhibitors against Ras and RbAp46. Similarly, knockdown of RbAp46 expression in the stable NIH3T3 cells "7-4" by shRNA decreased Ras-related lung metastasis using a xenograft nude mice model., Conclusions: We confirmed that RbAp46 is a Ha-ras (val12) up-regulated gene and binds with HDAC1 and Sp1. Furthermore, RbAp46 binds to the RECK promoter at the Sp1 site via recruitment by Sp1. RECK is subsequently activated, leading to increased MMP9 activity, which may lead to increased metastasis in vivo. Our findings of Ras upregulation of RbAp46 may lead to revealing a novel mechanism of Ras-related tumor cell metastasis.

The Infectious Diseases of Poverty journal, launched a year ago, is a platform to engage outside the traditional disciplinary boundaries, and disseminate high quality science towards the improvement of health. This paper reviews the milestone achievements during its first year of operation. The journal has filled an important niche, addressing some of the main priorities in the Global Report for Research on Infectious Diseases of Poverty. Highlights include the publication of three thematic issues on health systems, surveillance and response systems, as well as co-infection and syndemics. The thematic issues have foregrounded the importance and innovation that can be achieved through transdisciplinary research. The journal has been indexed by PubMed since April 2013, with the publication of a total of 38 articles. Finally, the journal is delivering to wider range readers both in developing and developed countries with sustained efforts with a focus on relevant and strategic information towards elimination of infectious diseases of poverty.

Introduction: The effect of socioeconomic status (SES) on stroke mortality at population level has been controversial. This study explores the association of SES in childhood and adulthood with stroke mortality, as well as variations in this association among countries/regions., Methods: Sex-specific stroke mortality at country level with death registry covering ≥ 70% population was obtained from the World Health Organization. Human Development Index (HDI) developed by the United Nations was chosen as the SES indicator. The associations between the latest available stroke mortality with HDI in 1999 (adulthood SES) and with HDI in 1960 (childhood SES) for the group aged 45-54 years among countries were examined with regression analysis. Age-standardized stroke mortality and HDI during 1974-2001 were used to estimate the association by time point., Results: The population data were available mostly for low-middle to high income countries. HDI in 1960 and 1999 were both inversely associated with stroke mortality in the group aged 45-54 years in 39 countries/regions. HDI in 1960 accounted for 37% of variance of stroke mortality among countries/regions; HDI in 1999 for 35% in men and 53% in women (P < 0.001). There was a quadratic relationship between age-standardized stroke mortality and HDI for the countries from 1974 to 2001: the association was positive when HDI < 0.77 but it became negative when HDI > 0.80., Conclusions: SES is a strong predictor of stroke mortality at country level. Stroke mortality increased with improvement of SES in less developed countries/region, while it decreased with advancing SES in more developed areas.

Background: Increased bone marrow lipid deposition in steroid-associated osteonecrosis (ON) implies that abnormalities in fat metabolism play an important role in ON development. The increase in lipid deposition might be explained by elevated adipogenesis of marrow mesenchymal stem cells (MSCs). However, it remains unclear whether there is a close association between elevated adipogenesis and steroid-associated ON development., Objective: The present study was designed to test the hypothesis that there might be a close association between elevated adipogenesis and steroid-associated ON development., Methods: ON rabbit model was induced based on our established protocol. Dynamic-MRI was employed for local intra-osseous perfusion evaluation in bilateral femora. Two weeks after induction, bone marrow was harvested for evaluating the ability of adipogenic differentiation of marrow MSCs at both cellular and mRNA level involving adipogenesis-related gene peroxisome proliferator-activated receptor gamma2 (PPARgamma2). The bilateral femora were dissected for examining marrow lipid deposition by quantifying fat cell number, fat cell size, lipid deposition area and ON lesions. For investigating association among adipogenesis, lipid deposition and perfusion function with regard to ON occurrence, the rabbits were divided into ON+ (with at least one ON lesion) group and ON- (without ON lesion) group. For investigating association among adipogenesis, lipid deposition and perfusion function with regard to ON extension, the ON+ rabbits were further divided into sub-single-lesion group (SON group: with one ON lesion) and sub-multiple-lesion group (MON group: with more than one ON lesion)., Results: Local intra-osseous perfusion index was found lower in either ON+ or MON group when compared to either ON- or SON group, whereas the marrow fat cells number and area were much larger in either ON+ or MON group as compared with ON- and SON group. The adipogenic differentiation ability of MSCs and PPARgamma2 expression in either ON+ or MON group were elevated significantly as compared with either ON- or SON group., Conclusion: These findings support our hypothesis that there is a close association between elevated adipogenesis and steroid-associated osteonecrosis development.