801 resultados para diversity-disease relationship


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Salmonellosis is a major health problem worldwide. Serovar Enteritidis has been a primary cause of Salmonella outbreaks in many countries. In Brazil, few molecular typing studies have been performed. The aims of this study were to molecularly type Salmonella Enteritidis strains isolated in Brazil in order to determine the genetic relationship between strains of food and human origin, as well as, to assess their pathogenic potential and antimicrobial resistance. A total of 128 S. Enteritidis strains isolated from human feces (67) and food (61) between 1986 and 2010 were studied. The genotypic diversity was assessed by ERIC-PCR and PFGE using Xbal, the antimicrobial resistance by the disc-diffusion assay and the presence of the SPI-1, SPI-2 and pSTV virulence genes assessed by PCR. The ERIC-PCR results revealed that 112 strains exhibited a similarity of >85.4% and the PFGE that 96 strains exhibited a similarity of >80.0%. Almost all strains (97.6%) harbored all 13 virulence genes investigated. Thirty-six strains (28.12%) were resistant to nalidixic acid. In conclusion, the nalidixic acid resistance observed after 1996 is indicative of an increase in the use of this drug. It may be suggested that these 128 strains might have descended from a common ancestor that differed little over 24 years and has been both contaminating food and humans and causing disease for more than two decades in Brazil. (c) 2012 Elsevier Ltd. All rights reserved.

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Human Parvovirus B19 (B19V) is a recognized cause of life-threatening conditions among patients with hemoglobinopathies. This study investigates B19V infection in patients with sickle cell disease and beta-thalassemia using different experimental approaches. A total of 183 individuals (144 with sickle cell disease and 39 with beta-thalassemia major) and 100 healthy blood donors were examined for B19V using anti-B19V IgG enzyme immunoassay, quantitative PCR, DNA sequencing, and phylogenetic analysis. Viremia was documented in 18.6% of patients and 1% of donors, and was generally characterized by low viral load (VL); however, acute infections were also observed. Anti-B19V IgG was detected in 65.9% of patients with sickle cell disease and in 60% of donors, whereas the patients with thalassemia exhibited relatively low seroreactivity. The seroprevalence varied among the different age groups. In patients, it progressively increased with age, whereas in donors it reached a plateau. Based on partial NS1 fragments, all isolates detected were classified as subgenotype 1A with a tendency to elicit genetically complex infections. Interestingly, quasispecies occurred in the plasma of not only patients but also donors with even higher heterogeneity. The partial NS1 sequence examined did not exhibit positive selection. Quantitation of B19V with a conservative probe is a technically and practically useful approach. The extensive spread of B19V subgenotype 1A in patients and donors and its recent introduction into the countryside of the Sao Paulo State, Brazil were demonstrated; however, it is difficult to establish a relationship between viral sequences and the clinical outcomes of the infection. J. Med. Virol. 84:16521665, 2012. (c) 2012 Wiley Periodicals, Inc.

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Background: Dengue is the most important mosquito-borne viral disease worldwide. Dengue virus comprises four antigenically related viruses named dengue virus type 1 to 4 (DENV1-4). DENV-3 was re-introduced into the Americas in 1994 causing outbreaks in Nicaragua and Panama. DENV-3 was introduced in Brazil in 2000 and then spread to most of the Brazilian States, reaching the neighboring country, Paraguay in 2002. In this study, we have analyzed the phylogenetic relationship of DENV-3 isolated in Brazil and Paraguay with viruses isolated worldwide. We have also analyzed the evolutionary divergence dynamics of DENV-3 viruses. Results: The entire open reading frame (ORF) of thirteen DENV-3 isolated in Brazil (n = 9) and Paraguay (n = 4) were sequenced for phylogenetic analysis. DENV-3 grouped into three main genotypes (I, II and III). Several internal clades were found within each genotype that we called lineage and sub-lineage. Viruses included in this study belong to genotype III and grouped together with viruses isolated in the Americas within the lineage III. The Brazilian viruses were further segregated into two different sub-lineage, A and B, and the Paraguayan into the sub-lineage B. All three genotypes showed internal grouping. The nucleotide divergence was in average 6.7% for genotypes, 2.7% for lineages and 1.5% for sub-lineages. Phylogenetic trees constructed with any of the protein gene sequences showed the same segregation of the DENV-3 in three genotypes. Conclusion: Our results showed that two groups of DENV-3 genotypes III circulated in Brazil during 2002-2009, suggesting different events of introduction of the virus through different regions of the country. In Paraguay, only one group DENV-3 genotype III is circulating that is very closely related to the Brazilian viruses of sub-lineage B. Different degree of grouping can be observed for DENV-3 and each group showed a characteristic evolutionary divergence. Finally, we have observed that any protein gene sequence can be used to identify the virus genotype.

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Das Ziel dieser Arbeit war es, mehr Informationen über unkonventionelle Gründe für Gärstockungen zu gewinnen und neue Wege zu finden, diese zu überwinden. Mikrobielle Sukzession und die chemische Zusammensetzung bei der Gärung wurden in zwei aufeinander folgenden Jahren in einem Weingut von der oberen Mosel in Deutschland studiert. Es gab keinen Hinweis darauf, dass die isolierten Bakterienspezies oder chemischen Komponenten von Most und Jungwein an schleppenden oder stockenden Gärungen beteiligt waren. Ferner konnte während dieser Arbeit gezeigt werden, dass Saccharomyces bayanus die dominierende Weinhefe in diesem Weingut war statt der klassischen und bekannten Weinhefe Saccharomyces cerevisiae. Während der Gärstockung konnte ein Dreifach-Hybrid Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus wachsen, Saccharomyces bayanus ersetzen und die Gärung beenden. Beide isolierten Hefestämme Saccharomyces bayanus Stamm HL 77 und der Dreifach-Hybrid Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus Stamm HL 78 konnten Glucose und Fructose von Anfang an verwerten und konnten bei niedrigen Temperaturen von 15 °C und in der Abwesenheit von Hefe-verwertbarem Stickstoff in Form von Ammonium wachsen, solange Aminosäuren im Medium vorhanden waren, im Gegensatz zu einer kommerziellen Saccharomyces cerevisiae-Starterkultur. Chemische Untersuchungen ergaben, dass Hefe-verwertbarer Stickstoff in dem kooperierenden Weingut mit einem Maximum von 160 mg/l zu Beginn der Gärung vorhanden war und auf 40 mg/L verringert war nach zwei Wochen. Aus diesem Grund sind beide isolierten Hefestämme interessant als Starterkulturen in diesem Weingut und dies kann neben der niedrigen Temperatur im Keller auch ein Grund sein, warum Saccharomyces cerevisiae nicht die dominierende Weinhefe in diesem Fall ist. Der Dreifach-Hybrid Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus Stamm HL 78 ist in der Lage, Fructose noch effizienter zu nutzen als Saccharomyces bayanus Stamm HL 77 und ist weniger abhängig von der Aminosäurekonzentration. Dieser Stamm wurde bereits erfolgreich bei diesem Projekt eingesetzt, um eine Gärstockung in dem kooperierenden Weingut zu beheben. Es ist bekannt, dass Saccharomyces-Hybride in der Weinherstellung vorkommen aber ihre Rolle bei der Überwindung von Gärstockungen wurde bisher noch nicht beschrieben. Diese Ergebnisse sind nützlich, um Gärstockungen zu vermeiden oder zu überwinden mit der selektiven Verwendung dieser Hefestämme in verschiedenen Stadien der Gärung. Das kooperierende Weingut, welches im oberen Qualitätssegment platziert ist, hatte jedes Jahr Probleme mit Gärstockungen. Daher ist die Anwendung der Dreifach-Hybriden Saccharomyces cerevisiae x Saccharomyces kudriavzevii x Saccharomyces bayanus Stamm HL 78 eine große Chance, Gärstockungen und finanzielle Verluste ohne kommerzielle Starterkulturen oder andere übliche Praktiken, die zu einer Veränderung des Aromaprofils führen können, zu vermeiden. Die beschriebenen Untersuchungen stellen ein Modell dar, um Gärstockungen auch in anderen Weingütern, die Spontangärungen anwenden, zu überwinden.

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The stress associated with providing care for a spouse diagnosed with Alzheimer's disease can have adverse effects on cardiovascular health. One potential explanation is that chronic caregiving stress may contribute to the development of atherosclerosis. The purpose of this study was to determine whether the duration that one has provided care is associated with the degree of atherosclerotic burden, as measured by carotid artery intima-media thickness (IMT). One hundred and ten Alzheimer caregivers [mean age 74 ± 8 (SD) years, 69% female] underwent in-home assessment of carotid artery IMT via B-mode ultrasonography. Data regarding medical history, blood pressure, and multiple indicators of caregiving stress were also collected. Multiple regression indicated that duration of care was positively associated with IMT measured in the internal/bifurcation segments of the carotid artery (β = 0.202, p = 0.044) independent of risk factors such as age, gender, body mass index, smoking history, sleep quality, hypertension status, and caregiving stressors. Duration of care was positively associated with IMT in the common carotid artery, but the relationship was not significant. These findings provide more evidence of the link between chronic caregiving stress and cardiovascular disease and indicate that enduring the experience of caregiving over a period of years might be associated with atherosclerotic burden.

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Gene duplication is one of the key factors driving genetic innovation, i.e., producing novel genetic variants. Although the contribution of whole-genome and segmental duplications to phenotypic diversity across species is widely appreciated, the phenotypic spectrum and potential pathogenicity of small-scale duplications in individual genomes are less well explored. This review discusses the nature of small-scale duplications and the phenotypes produced by such duplications. Phenotypic variation and disease phenotypes induced by duplications are more diverse and widespread than previously anticipated, and duplications are a major class of disease-related genomic variation. Pathogenic duplications particularly involve dosage-sensitive genes with both similar and dissimilar over- and underexpression phenotypes, and genes encoding proteins with a propensity to aggregate. Phenotypes related to human-specific copy number variation in genes regulating environmental responses and immunity are increasingly recognized. Small genomic duplications containing defense-related genes also contribute to complex common phenotypes.

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The association of measures of physical activity with coronary heart disease (CHD) risk factors in children, especially those for atherosclerosis, is unknown. The purpose of this study was to determine the association of physical activity and cardiovascular fitness with blood lipids and lipoproteins in pre-adolescent and adolescent girls.^ The study population was comprised of 131 girls aged 9 to 16 years who participated in the Children's Nutrition Research Center's Adolescent Study. The dependent variables, blood lipids and lipoproteins, were measured by standard techniques. The independent variables were physical activity measured as the difference between total energy expenditure (TEE) and basal metabolic rate (BMR), and cardiovascular fitness, VO$\rm\sb{2max}$(ml/min/kg). TEE was measured by the doubly-labeled water (DLW) method, and BMR by whole-room calorimetry. Cardiovascular fitness, VO$\rm\sb{2max}$(ml/min/kg), was measured on a motorized treadmill. The potential confounding variables were sexual maturation (Tanner breast stage), ethnic group, body fat percent, and dietary variables. A systematic strategy for data analysis was used to isolate the effects of physical activity and cardiovascular fitness on blood lipids, beginning with assessment of confounding and interaction. Next, from regression models predicting each blood lipid and controlling for covariables, hypotheses were evaluated by the direction and value of the coefficients for physical activity and cardiovascular fitness.^ The main result was that cardiovascular fitness appeared to be more strongly associated with blood lipids than physical activity. An interaction between cardiovascular fitness and sexual maturation indicated that the effect of cardiovascular fitness on most blood lipids was dependent on the stage of sexual maturation.^ A difference of 760 kcal/d physical activity (which represents the difference between the 25th and 75th percentile of physical activity) was associated with negligible differences in blood lipids. In contrast, a difference in 10 ml/min/kg of VO$\rm\sb{2max}$ or cardiovascular fitness (which represents the difference between the 25th and 75th percentile in cardiovascular fitness) in the early stages of sexual maturation was associated with an average positive difference of 15 mg/100 ml ApoA-1 and 10 mg/100 ml HDL-C. ^

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The medial arterial supply to 68 of the 72 coxofemoral joints of 36 medium to large breed dogs was examined ultrasonographically. The medial circumflex femoral artery and three branches were identified; the artery and its transverse branch were identified in all 68 joints, and the deep branch was identified in 61 joints, and the ascending branch was identified in 63. However, the acetabular and obturator branches were not identified. The pulsatility index, the mean velocity and the peak systolic velocity of the medial circumflex femoral artery were determined and associated with a radiographic score of degenerative coxofemoral joint disease and a lath distraction index (LDI). In joints with a LDI greater than 0.35, the pulsatility index was significantly lower (P=0.023) and its mean velocity was higher (P=0.005). However, no significant associations were observed in individual dogs when the measurements in both joints were taken into account.

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Little is known about the effects of smoking on inflammatory bowel diseases (IBD). However the co-occurrence of smoking and IBD often happens in ambulatory care. Smokers have a doubled risk of developing a Crohn's disease with a more active disease course. After quitting, a decrease in risk can be observed after only one year. An inverse relationship is found between smoking and ulcerative colitis. Smoking seems protective for the development of the disease and its course is less active among smokers. Smoking cessation transitorily increases the risk of developing ulcerative colitis. Nevertheless, continuing smoking cannot be justified among those patients given the risks of long-term extra-digestive effects. It is thus important to counsel all smokers with an IBD to quit smoking.

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One of the most widely accepted noncontraceptive benefits of oral contraceptive use is the reduction in the development of pelvic inflammatory disease (PID) and its sequelae in users. While much of the research over the past forty years has found an association between oral contraceptive use and reduced rates of PID [Senanayake, 1980], more recent studies have qualified and even challenged this widely held belief. [Henry-Suchet, 1997; Ness 1997; Ness, 2001] PID, an infection in the upper genital tract causing infertility and ectopic pregnancy, affects over one million women in the United States each year, exacting an enormous toll on women's reproductive and emotional health, as well as our economy. [CDC Factsheet, 2007] This thesis examines the public health implications of pelvic inflammatory disease and the use of oral contraceptives. Sixteen original studies are reviewed and analyzed, thirteen of which found a protective benefit with oral contraceptive use against PID and three more recent studies which found no protective benefit or association between oral contraceptive use and PID. Analysis of the research findings suggests a need for additional research, provider and patient education, and an increased government role in addressing the ongoing and significant public health concerns raised by current rates of Chlamydia- and gonorrheal-PID. ^

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Coronary artery disease (CAD) is the most common cause of morbidity and mortality in the United States. While Coronary Angiography (CA) is the gold standard test to investigate coronary artery disease, Prospective gated-64 Slice Computed Tomography (Prosp-64CT) is a new non-invasive technology that uses the 64Slice computed tomography (64CT) with electrocardiographic gating to investigate coronary artery disease. The aim of the current study was to investigate the role of Body Mass Index (BMI) as a factor affecting occurrence of CA after a Prosp-64CT, as well as the quality of the Prosp-64CT. Demographic and clinical characteristics of the study population were described. A secondary analysis of data on patients who underwent a Prosp-64CT for evaluation of coronary artery disease was performed. Seventy seven patients who underwent Prosp-64CT for evaluation for coronary artery disease were included. Fifteen patients were excluded because they had missing data regarding BMI, quality of the Prosp-64CT or CA. Thus, a total of 62 patients were included in the final analysis. The mean age was 56.2 years. The mean BMI was 31.3 kg/m 2. Eight (13%) patients underwent a CA within one month of Prosp-64CT. Eight (13%) patients had a poor quality Prosp-64CT. There was significant association of higher BMI as a factor for occurrence of CA post Prosp-64CT (P<0.05). There was a trend, but no statistical significance was observed for the association of being obese and occurrence of CA (P=0.06). BMI, as well as obesity, were not found to be significantly associated with poor quality of Prosp-64CT (P=0.19 and P=0.76, respectively). In conclusion, BMI was significantly associated with occurrence of CA within one month of Prosp-64CT. Thus, in patients with a higher BMI, diagnostic investigation with both tests could be avoided; rather, only a CA could be performed. However, the relationship of BMI to quality of Prosp-64CT needs to be further investigated since the sample size of the current study was small.^

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Supermarket nutrient movement, a community food consumption measure, aggregated 1,023 high-fat foods, representing 100% of visible fats and approximately 44% of hidden fats in the food supply (FAO, 1980). Fatty acid and cholesterol content of foods shipped from the warehouse to 47 supermarkets located in the Houston area were calculated over a 6 month period. These stores were located in census tracts with over 50% of a given ethnicity: Hispanic, black non-Hispanic, or white non-Hispanic. Categorizing the supermarket census tracts by predominant ethnicity, significant differences were found by ANOVA in the proportion of specific fatty acids and cholesterol content of the foods examined. Using ecological regression, ethnicity, income, and median age predicted supermarket lipid movements while residential stability did not. No associations were found between lipid movements and cardiovascular disease mortality, making further validation necessary for epidemiological application of this method. However, it has been shown to be a non-reactive and cost-effective method appropriate for tracking target foods in populations of groups, and for assessing the impact of mass media nutrition education, legislation, and fortification on community food and nutrient purchase patterns. ^