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21.
The development of molecular technologies applied to environmental studies has shown that even in highly industrialized countries there is a high prevalence of viruses in the environment that represents an important impact on public health and substantial economic losses mainly related to the transmission of viruses through water and food. Significant concentrations of viruses are detected in the water flowed to the environment and in the biosolids generated in wastewater treatment plants. This work describes the general characteristics of the environmental contamination by viruses principally by emergent viruses, with a special emphasis on the hepatitis E virus (HEV) and the human polyomaviruses as the environmental contaminants more recently identified in industrialized countries. It has been shown that there is a high prevalence of the human polyomaviruses BKV and JCV in urban sewage in all studied countries, implying a potential transmission of these viruses and their potential oncogenic genes through the oral route. Recent studies have shown that the epidemiological pattern of the HEV infection in industrialized countries is complex and that a diversity of HEV strains simultaneously infects the population. The control of the viral contamination requires the standardization of molecular techniques and the development of a surveillance program for the evaluation of the viral parameters and to reduce the dissemination of already established diseases and emergent viral infections.  相似文献   
22.
Several studies have reported a global decline in seminal quality over the years. The objective of this study was to describe the semen donor population of Uruguay through comparing data of successive samples banked by the same donors and the analysis of their semen and physical characteristics, ancestry origin and educational level. A total of 3,449 ejaculated samples collected from 71 donors, cryobanked between 1989 and March 2017 at Fertilab, were analysed. Results revealed a mean age of 23.90 ± 3.98 years, an average weight of 74.95 ± 1.09 kg and a mean height of 1.78 ± 0.06 m. The majority of the donors trace their origin to Europe (74.65%, 53/71) and 66.19% (47/71) have a level of education higher than secondary school. We observed longitudinal differences in two parameters, that is sperm concentration and semen volume. Sperm concentration declined, while semen volume increased significantly over the 28-year period. The results of the present study are in accordance with that of previous articles that also reported a decline in sperm concentration over time. However, no differences were observed in total sperm number per ejaculate due to the increase in semen volume values, thus reflecting no real changes in sperm production over time.  相似文献   
23.
OBJECTIVE: Although possible implications of nitric oxide in the pathophysiology of liver cirrhosis have been extensively studied, until now few articles have addressed the assessment of nitric oxide production in primary biliary cirrhosis. This study was directed to evaluate circulating nitrosyl-hemoglobin levels as well as neutrophil elastase and soluble adhesion molecule concentrations in this condition, by assuming these parameters as possible markers of either inflammatory response or neutrophil activation. METHODS: Laboratory investigations were performed in 30 patients with primary biliary cirrhosis, in 13 patients with postviral and/or alcoholic cirrhosis, and in a group of eight subjects with chronic hepatitis. RESULTS: Although no difference was detected with respect to chronic hepatitis subjects, higher levels of nitrosyl-hemoglobin adducts were found in primary biliary cirrhosis patients than in postviral or alcoholic cirrhotics and in normal subjects (3.55+/-1.75 arbitrary units vs 1.95+/-0.57 and 0.84+/-0.34, p = 0.0004 and p < 0.0001, respectively). Similarly, more elevated concentrations of neutrophil elastase (213.7+/-192.0 microg/L vs 51.1+/-34.3 and 38.0+/-11.5, p < 0.0001 and p < 0.0001, respectively) as well as of soluble forms of intercellular adhesion molecule 1 and endothelial-leukocyte adhesion molecule 1 were shown in primary biliary cirrhosis patients than in subjects with cirrhosis of other etiologies and in controls. CONCLUSIONS: Highly enhanced nitric oxide production in primary biliary cirrhosis could be related to the development of strong inflammation and at least partially to neutrophil activation, thus suggesting a putative role of these cellular mediators in the development of liver damage owing to their ability to synthesize and release a wide variety of important factors, including elastase and nitric oxide.  相似文献   
24.
Studies examining the prevalence of zoonotic agents in the Caribbean are very limited. The objective of this study was to examine the seroprevalence of seven zoonotic agents among individuals residing on 10 English-speaking Caribbean countries. Sera from healthy, pregnant women were collected from Antigua-Barbuda, Belize, Bermuda, Dominica, Grenada, Jamaica, Montserrat, St. Kitts-Nevis, St. Lucia, and St. Vincent-Grenadines and tested for the presence of IgG antibodies to dengue virus, hepatitis E virus, hantaviruses, leptospiral agents, spotted fever group rickettsiae (SFGR), typhus group rickettsiae (TGR), and Coxiella burnetii (Q fever). The highest seroprevalence values were observed for dengue virus, SFGR, and leptospirosis, although the lowest seroprevalence values were observed for hepatitis E virus, C. burnetii, and TGR. Antibodies to hantaviruses were not detected in any individuals.  相似文献   
25.
BACKGROUND: HIV infection has increased within the Latina community more than in any other ethnic or racial group within the United States. Latinas comprise only 13% of the U.S. population, yet they account for 20% of the cumulative reported cases of AIDS. OBJECTIVES: The purpose of the study was to evaluate a randomized culturally tailored intervention to prevent high-HIV-risk sexual behaviors for Latina women residing in urban areas. METHODS: Mexican and Puerto Rican women (18-44 years of age; N = 657) who were sexually active during the previous 3 months were recruited and randomized into intervention and control groups. The intervention, facilitated by bilingual, bicultural, trained Latina women, consisted of culturally tailored sessions on understanding their bodies, HIV/AIDS and sexually transmitted diseases, condoms (myths and use), negotiating safer sex practices, violence prevention, and partner communication. Bivariate and multivariate analyses assessed changes from baseline. RESULTS: The intervention improved HIV knowledge, partner communication, risk-reduction behavioral intentions, and condom use, and decreased perceived barriers to condom use. DISCUSSION: The efficacy of a culturally-sensitive intervention to reduce HIV/AIDS-risk behaviors in Latina women was demonstrated in the current study.  相似文献   
26.
Hispanic women (HW) are disproportionately affected by HIV, however, little is known regarding their perceived susceptibility for acquiring HIV (SAHIV). We studied predictive factors for perceiving SAHIV among HW. Participants (88.5%) reported not feeling SAHIV. Women who felt SAHIV, had a significant probability of reporting a higher chance for acquiring HIV from their partner's actions (OR 9.75), and a higher probability of not being tested for HIV (OR 2.05). Educational strategies to increase perception of SAHIV and HIV testing knowledge would be beneficial giving emphasis to women who do not perceive to be at risk from their partner's actions.  相似文献   
27.
Little is known about attitudes toward physician‐assisted suicide (PAS) in various ethnic groups. This study compares attitudes held by older Mexican Americans and non‐Hispanic whites and examines subject characteristics that may influence their responses. A convenience sample of 100 older Mexican Americans and 108 non‐Hispanic whites (n=208) aged 60 to 89 were recruited from four primary care community‐based practice sites in San Antonio, Texas. Interview items measured attitudes toward PAS, cognitive status, functional status, and religiosity. Older Mexican Americans (52.7%) reported stronger agreement than non‐Hispanic whites (33.7%) with PAS. Male sex (odds ratio (OR)=2.62, 95% confidence interval (CI)=1.09–6.35) predicted agreement with legalization in Mexican Americans, whereas lower religiosity scores (OR=0.84, 95% CI=0.75–0.94) were predictive of agreement in older non‐Hispanic whites. This study is the first to find positive attitudes among community‐dwelling older Mexican Americans toward PAS that are higher than those of older non‐Hispanic white adults. Sex and religious views were important determinants of positive attitudes toward PAS. Larger, more‐generalizable studies should be conducted to confirm the attitudinal patterns that have been identified in this study.  相似文献   
28.
BACKGROUND/AIMS: In industrialized countries hepatitis E virus (HEV) infection is rare and its diagnosis is difficult because the utility of available tests is not well established. METHODS: We studied the presence of acute HEV infection markers in a cluster of 11 cases of acute hepatitis with IgG anti-HEV antibodies. RESULTS: Three cases were confirmed as acute hepatitis E and 8 as presumptive hepatitis E, two as a past HEV infection and one could not be determined. Three different HEV strains were identified in serum from 3 patients. Two strains belonged to genotype 3, the predominant genotype found in local urban sewage and the other strain belonged to genotype 1 and was considered an imported strain. CONCLUSIONS: Our findings demonstrate the presence of some autochthonous, sporadic acute hepatitis E cases as well as an imported case in our area and the transitory nature of virological and serological markers for HEV.  相似文献   
29.
30.
Nonalcoholic fatty liver disease (NAFLD) ranges from simple steatosis (SS) to nonalcoholic steatohepatitis (NASH). Though liver-related risk seems confined to NASH, it is currently unclear whether NASH has a higher risk of cardiovascular disease (CVD) and diabetes than SS as a result of the coexistence of obesity and other cardiometabolic confounders. Adipose tissue is an emerging modulator of liver disease in NAFLD and of cardiometabolic disease in the general population. We evaluated in SS and NASH (1) glucose homeostasis and cardiovascular risk profile and (2) the effect of adipose tissue dysfunction, assessed in fasting conditions and postprandially, on liver injury, glucose and lipoprotein metabolism, and markers of early atherosclerosis. Forty nonobese, nondiabetic, normolipidemic biopsy-proven NAFLD patients (20 with SS and 20 with NASH) and 40 healthy subjects, matched for overall/abdominal adiposity and metabolic syndrome, underwent an oral fat load test, with measurement of plasma triglyceride-rich lipoproteins, oxidized low-density lipoproteins, adipokines, and cytokeratin-18 fragments, and an oral glucose tolerance test with minimal model analysis to yield glucose homeostasis parameters. Circulating endothelial adhesion molecules were measured, and adipose tissue insulin resistance (adipose IR) index and visceral adiposity index were calculated. Despite similar fasting values, compared to SS, NASH showed a more atherogenic postprandial lipoprotein profile, an altered adipokine response (i.e., higher resistin increase and an adiponectin fall), and hepatocyte apoptosis activation after fat ingestion. Adipose IR index, endothelial adhesion molecules, and hepatic insulin resistance progressively increased across NAFLD stages. NASH, but not SS, showed an impaired pancreatic β-cell function. On multiple regression analysis, adipose IR index and postprandial adiponectin independently predicted liver histology and altered cardiometabolic parameters. Conclusion: Adipose tissue dysfunction, including a maladaptive adipokine response to fat ingestion, modulates liver injury and cardiometabolic risk in NAFLD. (HEPATOLOGY 2012;56:933-942).  相似文献   
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