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Christine Murto Frédérique Chammartin Karolin Schwarz Lea Marcia Melo da Costa Charles Kaplan Jorg Heukelbach 《PLoS neglected tropical diseases》2013,7(9)
Leprosy remains a public health problem in Brazil with new case incidence exceeding World Health Organization (WHO) goals in endemic clusters throughout the country. Migration can facilitate movement of disease between endemic and non-endemic areas, and has been considered a possible factor in continued leprosy incidence in Brazil. A study was conducted to investigate migration as a risk factor for leprosy. The study had three aims: (1) examine past five year migration as a risk factor for leprosy, (2) describe and compare geographic and temporal patterns of migration among past 5-year migrants with leprosy and a control group, and (3) examine social determinants of health associated with leprosy among past 5-year migrants. The study implemented a matched case-control design and analysis comparing individuals newly diagnosed with leprosy (n = 340) and a clinically unapparent control group (n = 340) without clinical signs of leprosy, matched for age, sex and location in four endemic municipalities in the state of Maranhão, northeastern Brazil. Fishers exact test was used to conduct bivariate analyses. A multivariate logistic regression analysis was employed to control for possible confounding variables. Eighty cases (23.5%) migrated 5-years prior to diagnosis, and 55 controls (16.2%) migrated 5-years prior to the corresponding case diagnosis. Past 5 year migration was found to be associated with leprosy (OR: 1.59; 95% CI 1.07–2.38; p = 0.02), and remained significantly associated with leprosy after controlling for leprosy contact in the family, household, and family/household contact. Poverty, as well as leprosy contact in the family, household and other leprosy contact, was associated with leprosy among past 5-year migrants in the bivariate analysis. Alcohol consumption was also associated with leprosy, a relevant risk factor in susceptibility to infection that should be explored in future research. Our findings provide insight into patterns of migration to localize focused control efforts in endemic areas with high population mobility. 相似文献
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The limiting steps of ethylene-dependent (methylsulfanyl)alkanoate ester biosynthesis have been investigated in this study, using closely related Actinidia chinensis genotypes and the commercial cultivar ‘Hort16A’. Quantification of methylsulfanyl-compounds from the headspace of ethylene-producing kiwifruits revealed little variation in their volatile composition but remarkable differences in the magnitude of the fruit volatile levels. To test whether the variations in fruit volatile levels can be correlated with the genotype-specific apparent catalytic efficiency, the initial slope of the substrate response curve (V′MaxKM−1 where V′Max is the apparent VMax in a crude extract) was evaluated for total alcohol acyltransferase (EC 2.3.1.84) activity. The V′MaxKM−1 values of different (methylsulfanyl)alkyl-CoAs were in a similar range for most genotypes, which suggests substrate availability as the limiting factor for (methylsulfanyl)alkanoate ester synthesis in these kiwifruit. Furthermore, gene expression analysis of acyltransferase expressed sequence tags points towards the action of multiple isozymes for (methylsulfanyl)alkanoate ester synthesis, emphasizing the central role of substrate levels on final ester concentrations. Volatile levels of the potential precursor methional were increased in ethylene-producing A. chinensis kiwifruit and a close connection between (methylsulfanyl)alkanoate ester formation and ethylene synthesis in plants is proposed. Finally, a possible biosynthetic pathway is presented. 相似文献
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Karolin Yanar Zeynep Mine Coskun Alisa Bahar Beydogan Seval Aydin Sema Bolkent 《Journal of cellular biochemistry》2019,120(9):16219-16228
Diabetes mellitus is a complex, multifactorial disorder that is attributed to pancreatic β cell dysfunction. Pancreatic β cell dysfunction results in declining utilization of glucose by peripheral tissues as kidney and it leads to nephropathy. Excessive production and accumulation of free radicals and incapable antioxidant defense system lead to impaired redox status. Macromolecular damage may occur due to impaired redox status and also immune imbalance. Δ9-Tetrahydrocannabinol (THC) is the main active ingredient in cannabis. THC acts as an immunomodulator and an antioxidant agent. Our aim was to evaluate the effects of THC in the diabetic kidney. We analyzed macromolecular damage biomarkers as protein carbonyl (PCO), lipid hydroperoxide (LHP), malondialdehyde (MDA), 8-hydroxy-2′-deoxyguanosine (8-OHdG), and antioxidant defense system biomarkers as thiol fractions (T-SH, NP-SH, P-SH) and Cu/Zn-superoxide dismutase activity for the antioxidative effects of THC. Furthermore, mRNA expression of Krüppel-like factor-4, secreted immunopositive cell number changes of interleukin-6, nuclear factor κβ (NF-κβ), and peroxisome proliferator-activated receptor-γ and tumor necrosis factor α (TNF-α) levels were analyzed for the immunomodulatory activity of THC. Diabetic rats showed significantly increased levels of PCO, LHP, MDA, and 8-OHdG when compared with controls (P < 0.05 for each parameter). THC significantly reduced the elevated levels of PCO and 8-OHdG (P < 0.05 for both parameters) and also LHP and MDA levels were insignificantly reduced by THC. Also, thiol fractions insignificantly increased in THC administered diabetic kidney when compared with diabetic rats. The NF-κβ cell number significantly decreased in the diabetic rats treated with THC compared with the diabetic group. According to our data, THC has ameliorative effects on the impaired redox status of diabetic kidney and also it acts as an immunomodulator. Therefore, THC might be used as a therapeutic agent for diabetic kidneys but its usage in the healthy kidney may show adverse effects. 相似文献
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Cellular senescence is a state of permanent replicative arrest that allows cells to stay viable and metabolically active but resistant to apoptotic and mitogenic stimuli. Specific, validated markers can identify senescent cells, including senescence-associated β galactosidase activity, chromatin alterations, cell morphology changes, activated p16- and p53-dependent signaling and permanent cell cycle arrest. Senescence is a natural consequence of DNA replication-associated telomere erosion, but can also be induced prematurely by telomere-independent events such as failure to repair DNA double strand breaks. Here, we review the molecular pathways of senescence onset, focussing on the changes in chromatin organization that are associated with cellular senescence, particularly senescence-associated heterochromatin foci formation. We also discuss the altered dynamics of the DNA double strand break response within the context of aging cells. Appreciating how, mechanistically, cellular senescence is induced, and how changes to chromatin organization and DNA repair contributes to this, is fundamental to our understanding of the normal and premature human aging processes associated with loss of organ and tissue function in humans. 相似文献
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Soluble CD14 (sCD14) and IL-18 are markers and mediators of the innate immune response, and their plasma levels candidate biomarkers of HCV treatment effects and outcome. Here, we retrospectively studied sCD14 and IL-18 over the course of interferon-based treatment of HCV genotype 1 infection, with the aim to investigate the impact of direct-acting antivirals (DAAs) on the dynamics and relationships between these biomarkers and treatment effects and outcome. Two cohorts were followed longitudinally; one treated with standard dual therapy of pegylated IFNα and ribavirin, and one cohort receiving triple therapy including Telaprevir. sCD14 and IL-18 were measured before and during treatment and analyzed in relation to treatment effects. The initial analysis confirmed two patterns previously observed in patients with HCV/HIV-1 co-infection: Baseline levels of sCD14 were significantly lower in patients that went on to clear HCV infection in response to IFNα and ribavirin, and sCD14 levels were strongly induced during the course of this treatment. Interestingly, baseline levels of sCD14 and IL-18 in combination predicted treatment outcome in dual therapy better than either marker alone. Notably, these associations were weaker with the addition of Telaprevir to the treatment regimen, suggesting that the relationships between innate immune activation and outcome were altered and diminished by inclusion of a DAA in the treatment. In triple therapy, the dynamic increase of sCD14 in response to treatment was higher in patients clearing the virus, suggesting that the innate response to interferon is still significantly associated with outcome in patients treated with DAA-containing regimens. These results support the notion that levels of innate immune activation before and during treatment are associated with interferon-based treatment outcome. Furthermore, the addition of Telaprevir significantly alters the dynamics and relationships between innate immune biomarkers and treatment effects and outcome. 相似文献
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Daniel Schmidt Christian Kollan Gerd F?tkenheuer Eugen Schülter Hans-Jürgen Stellbrink Christian Noah Bj?rn-Erik Ole Jensen Matthias Stoll Johannes R. Bogner Josef Eberle Karolin Meixenberger Claudia Kücherer Osamah Hamouda Barbara Bartmeyer 《PloS one》2014,9(8)