Immunoglobulin G subclasses in antibody responses to St. Louis encephalitis virus infections.

The aim of this study was to recognize the specific antiviral response patterns of IgG1, IgG2, IgG3 and IgG4 subclasses, elicited during St. Louis encephalitis virus (SLEV) infection in humans. Eighty-five samples of human sera from 44 patients with SLEV infection were obtained between days 1 and 365 or later, after onset of the disease. These samples were processed by immunofluorescence assay for detection of IgG1-, IgG2-, IgG3- and IgG4-specific antibodies. We demonstrate the presence of all isotypes of IgG for more than a year in patients infected with SLEV. However; isotype IgG1 was present at the highest titers, with a peak between days 8 and 30 after onset of the disease.

Identification of dietary patterns in urban population of Argentina: study on diet-obesity relation in population-based prevalence study.

BACKGROUND/OBJECTIVES: In Argentina, obesity prevalence rose from 14.6% in 2005 to 20.8% in 2013. Although the number of studies on noncommunicable diseases and dietary patterns as a unique dietary exposure measure has increased, information on this topic remains scarce in developing countries. This is the first population-based study investigating the association between diet and obesity using a dietary pattern approach in Argentina. We aimed (a) to identify current dietary patterns of the population of Córdoba city, (b) to investigate its association with obesity prevalence, and (c) to identify and describe dietary patterns from the subgroup of people with obesity. SUBJECTS/METHODS: The Córdoba Obesity and Diet Study (CODIES) was conducted in Córdoba city by using a random sample of n = 4,327 subjects between 2005 and 2012. Empirically derived dietary patterns were identified through principal component factor analysis. A multiple logistic regression analysis was used to investigate the association of dietary patterns with obesity. RESULTS: Four dietary patterns were identified, called "Starchy-Sugar", "Prudent", "Western", and "Sugary drinks". High scores for the "Western" pattern (with strongest factor loading on meats/eggs, processed meats, and alcohol) showed a positive association with obesity (OR: 1.33, 95% CI: 1.06-1.67, for third versus first tertile of factor score). "Meats/Cheeses" and "Snacks/Alcohol" patterns emerged in people with obesity. CONCLUSIONS: The findings suggest that high adherence to the "Western" pattern promoted obesity in this urban population. In addition, people with obesity showed characteristic dietary patterns that differ from those identified in the overall population.

Meat cooking habits and risk of colorectal cancer in Córdoba, Argentina.

OBJECTIVE: Colorectal cancer is the third cause of death among women and the fifth among men in Córdoba, Argentina. We previously reported colorectal cancer to be associated with a high intake of fatty meats and bovine viscera and inversely associated with dietary fiber intake. In this study, we investigated the role of method of cooking meat and preferences in browned surfaces in the risk of colorectal cancer. METHODS: A case-control retrospective study was carried out by interviewing 296 patients and 597 control subjects with a food-frequency questionnaire. Meat consumption and preferred cooking procedures (boiled, roasted, barbecued, cooked in a flat iron-pan without fat, and fried) were investigated. Odds ratios and 95% confidence intervals were obtained by unconditional logistic regression analysis. RESULTS: Barbecuing was the cooking method preferred by men, whereas iron-pan cooking was favored by women; frying was the least favored method. Fatty beef, sausages, and bovine viscera were preferentially barbecued or boiled, whereas lean beef was mainly roasted, iron-pan cooked, or fried. Chicken was barbecued or roasted. The multivariate relative risks (adjusted by age, sex, social stratum, and total energy intake) for preferring darkly browned surfaces were significantly associated with an increased risk for all cooking procedures (odds ratio, 4.57; 95% confidence interval, 3.10 to 6.73). No associations were found for red roasted or for boiled meats. CONCLUSION: Increased risk seems to be related to cooking temperature and close contact of the food to the heating source, because higher risks were observed for heavily browned surfaces when meats were barbecued or iron-pan cooked.

Breast cancer mortality trends and patterns in Córdoba, Argentina in the period 1986-2006.

To estimate the mortality trends and spatial patterns for breast cancer in Córdoba (Argentina) in the period 1986-2006 taking into account age, calendar year, and birth cohort effects. Mortality data were provided by the Department of Statistics, Ministry of Health of Córdoba. Time trends in breast cancer mortality were analyzed using joinpoint analysis and age-period-cohort models. A random-intercept log-linear model was also used to assess the spatial pattern. Breast cancer age standardized mortality rates rose by 1.4% (95% confidence interval 0.2-2.6) per year from 1986 to 1997, and thereafter both breast and total cancer rates declined [-2.5% (-4 to -1.0) and -1.6% (-2.3 to -0.8), respectively]. In age-specific analysis the decline was mainly at age 20-49 years [-2.4% (-4 to -0.9)]. Rates over most recent calendar years decreased, mainly in the most urbanized districts. Age-period-cohort models for Córdoba province and Córdoba Capital showed a favorable cohort effect for generations born after 1955. A decreasing trend in breast cancer mortality was found in Córdoba, especially at younger ages and in most urbanized areas. This could be attributed to some unidentified favorable factors in generations born after 1955.

Overweight and obesity: Prevalence and their association with some social characteristics in a random sample population-based study in Córdoba city, Argentina.

BACKGROUND: Obesity has become a threat to public health, as the epidemic is not confined to developed countries but is affecting many developing countries. Because obesity is known to vary according to socio-cultural factors, including socio-economic position and social roles, a multi-stage random sample population-based study was conducted in Córdoba, Argentina, from January 2005 to December 2006, to explore the effect of selected social factors on the prevalence of obesity. METHODS: Information was obtained about demographic, anthropometric, lifestyle, dietary and physical activity characteristics. Logistic regression (LR) and proportional odds models (POM) were used in data analysis. RESULTS: The prevalence of overweight and obesity was 52 and 17%, respectively. LR models revealed that overweight was positively associated with gender (men), decreasing socio-economic status (SES), married and divorced status and negatively with increasing levels of physical activity whereas obesity was positively associated with decreasing SES levels, married status and negatively associated with physical activity levels. POM revealed strong associations between variables and the outcomes and an effect modification among women aged 30 years or older with a low SES. CONCLUSIONS: Our data indicate a high prevalence of overweight and obesity in this population; several social factors and lifestyle characteristics are associated with both overweight and obesity. However, a prospective cohort study would be needed to investigate causality.

Occurrence of toxic cyanobacterial blooms in San Roque Reservoir (Córdoba, Argentina): a field and chemometric study.

We evaluated the presence of cyanobacterial blooms in San Roque Reservoir (Córdoba, Argentina). Cyanobacterial blooms and water samples were collected over 4 years (1998-2002). We confirmed the presence of microcystin-LR and microcystin-RR in 97% of these blooms. The total amount of microcystin (MC) ranged between 5.8 and 2400.0 microg x g(-1) of freeze-dried bloom material. These values suggest that guidelines for safe water consumption and recreational use should be established for this reservoir. Twenty-eight physical and chemical parameters were measured in water samples and evaluated by discriminant analysis (DA). A first DA was used to evaluate the factors promoting cyanobacteria occurrence, identifying nine parameters following three patterns associated with cyanobacterial growth. Inorganic phosphorous was found to promote the presence of blooms, whereas the highest proliferation of cyanobacteria was observed in the presence of smaller amounts of carbonate, bicarbonate, sulfate, and fecal coliform bacteria. The results observed during our fieldwork, analyzed using DA, agreed with the results of other laboratory studies, thus confirming the usefulness of DA to help with the evaluation of a complicated environmental data matrix. A second DA, using only water samples collected during the presence of cyanobacteria blooms, identified another nine parameters. The analysis of these parameters allowed us to identify certain environmental factors that could lead to the dominance of toxic strains, thus increasing the amount of MC. The results showed that, in our case, an increase in the water temperature was associated with higher amounts of MC per dry weight unit, whereas an increase in the concentrations of ammonia-nitrogen and iron were associated with lower amounts of MC, thus disfavoring the dominance of toxic strains.