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I Peres

Publications and source records attributed to I Peres.

7 recordsLinked to original sources
PubMed2006

A characterization of selected endocrine disruptor compounds in a Portuguese wastewater treatment plant.

Anthropogenic compounds that are able to disrupt the endocrine system of wildlife species are a major cause for concern and have led to a demand for new screening methods. The identification and quantification of endocrine disruptor compounds at wastewater treatment plant is of major interest to assess the endocrine activity of wastewater treatment plant discharges into the environment. This study consists of a preliminary survey of concentrations of previously selected endocrine disruptor compounds, undertaken to establish environmental concentrations and to support a biological program assay exposing freshwater fish to them. Selected endocrine disrupting chemicals (APEs, bisphenol A and 17 beta-estradiol) were measured in samples from a wastewater treatment plant located in Lisbon (Portugal), using recent commercial enzyme-linked immunosorbent assay kits and also LC-MS/MS. The results show that the wastewater treatment plant treatment process is efficient on the removal of target endocrine disruptor compounds. However, environmentally significant concentrations are still present in the treated effluent. The results also show that enzyme-linked immunosorbent assay kit is suitable for routine analysis of the selected compounds. The results are also useful since the wastewater treatment plant is located in a Mediterranean region, which results in an effluent with its own characteristics.

Benzhydryl Compounds↗
PubMed2005

Comparative study of the estrogenic responses of mirror carp (Cyprinus carpio) exposed to treated municipal sewage effluent (Lisbon) during two periods in different seasons.

To assess the estrogenic potency of the treated domestic sewage effluent from a sewage treatment plant (STP) located in Lisbon (Chelas), 60 mirror carp (Cyprinus carpio) were exposed to different concentrations of the sewage effluent (0%, 25%, 50% and 100%) for two periods of 28 days in two different seasons (winter/spring). Vitellogenin induction in males was used as a biomarker of exposure to xenoestrogens. At the end of the experiment, blood samples were taken for vitellogenin analysis and the fish were sacrificed and dissected. Gonad samples were taken for histological evaluation of the sewage effects. The results showed an increase in vitellogenin induction in exposed fish, both males and females, depending on the different dilutions of the sewage effluent. In comparison with controls, the gonadosomatic index decreased significantly (P < 0.05) in fish exposed to 100% treated effluent. Although statistically not significant, the hepatosomatic index (HSI) was high in all exposed fish. Histological abnormalities in fish gonads were evaluated and related to the different percentages of sewage effluent. Seasonal variations found in estrogenic responses were attributed to weather influences on sewage dilution.

Animals↗
PubMed2005

Gender and regional differences in perceived job stress across Europe.

BACKGROUND: Over the last 20 years stress at work has been found to be predictive of several conditions such as coronary heart disease, high blood pressure and non-specific sick leave. The Karasek demand/control/strain concept has been the most widely used in prospective epidemiological studies. OBJECTIVES: To describe distribution in Karasek's demand/control (DC) dimensions as well as prevalence of strain in samples from different parts of Europe grouped into three regions (South, Middle, Sweden), adjusting for occupation. To describe gender differences in Karasek's DC dimensions along with strain prevalence and assess the regional stability of those differences in different occupational groups. DESIGN: The Job stress, Absenteeism and Coronary heart disease in Europe (JACE) study, a Concerted Action (Biomed I) of the European Union, is a multicentre prospective cohort epidemiological study: 38,019 subjects at work aged 35-59 years were surveyed at baseline. Standardised techniques were used for occupation coding (International Standardised Classification of Occupations) and for the DC model (Karasek scale): five items for the psychological demand and nine items for the control or decision latitude dimensions, respectively. RESULTS: A total of 34,972 subjects had a complete data set. There were important regional differences in the Karasek scales and in prevalence of strain even after adjustment for occupational class. Mean demand and control were higher in the Swedish centres when compared to two centres in Milano and Barcelona (Southern region) and values observed in four centres (Ghent, Brussels, Lille and Hoofddorp) in Middle Europe were closer to those observed in the Southern cities than to those obtained in the Swedish cities. Clerks (ISCO 4) and, more specifically, office clerks (ISCO 41) exhibited the smallest regional variation. In a multivariate model, the factor 'region' explained a small fraction of total variance. In the two Southern centres as well as in the four Middle European centres, men perceived marginally less job-demand as compared to women whereas the reverse was observed in the two Swedish centres. Differences were larger for control: men appeared to perceive more control at work than did women. In a multivariate model, gender explained a small fraction whereas occupational level explained a large fraction of the variance. CONCLUSIONS: In this standardised multicentre European study Karasek's DC model showed large gender and occupational differences whereas geographic region explained a small fraction of the total DC variance, notwithstanding large differences in labour market and working conditions as pointed out by the European Commission as recently as 2000.

Adult↗
PubMed2005

Estrogenic effects in crucian carp (Carassius carassius) exposed to treated sewage effluent.

To assess the estrogenicity of a municipal sewage treatment plant, sexually mature crucian carp of both sexes were exposed for 28 days to domestic treated sewage effluent running with a constant flow of water, with tap water and with different concentrations of the sewage effluent (25%, 50% and 100%). Vitellogenin (VTG), gonadosomatic index (GSI), hepatosomatic index (HSI), and histological abnormalities were used to assess the estrogenic potency of the effluent. Results show a significant (P<0.05) increase in VTG levels in all exposed male fish. A significant (P<0.05) reduction in the GSI was only observed in fish exposed to 100% effluent. Morphological changes were detected by histological evaluation, revealing severe effects on the testes. Spermatogenesis was progressively reduced to total inhibition in fish exposed to 100% effluent. One of the most pronounced effects detected was the presence of oocytes in male gonads, observed in 20% of males exposed to 100% sewage effluent.

Animals↗
PubMed1999

Detection of an archaic clone of Staphylococcus aureus with low-level resistance to methicillin in a pediatric hospital in Portugal and in international samples: relics of a formerly widely disseminated strain?

Close to half of the 878 methicillin-resistant Staphylococcus aureus (MRSA) strains recovered between 1992 and 1997 from the pediatric hospital in Lisbon were bacteria in which antibiotic resistance was limited to beta-lactam antibiotics. The other half were multidrug resistant. The coexistence of MRSA with such unequal antibiotic resistance profiles prompted us to use molecular typing techniques for the characterization of the MRSA strains. Fifty-three strains chosen randomly were typed by a combination of genotypic methods. Over 90% of the MRSA strains belonged to two clones: the most frequent one, designated the "pediatric clone," was reminiscent of historically "early" MRSA: most isolates of this clone were only resistant to beta-lactam antimicrobials and remained susceptible to macrolides, quinolones, clindamycin, spectinomycin, and tetracycline. They showed heterogeneous and low-level resistance to methicillin (MIC, 1.5 to 6 microg/ml), carried the ClaI-mecA polymorph II, were free of the transposon Tn554, and showed macrorestriction pattern D (clonal type II::NH::D). The second major clone was the internationally spread and multiresistant "Iberian" MRSA with homogeneous and high-level resistance to methicillin (MIC, >200 microg/ml) and clonal type I::E::A. Surprisingly, the multidrug-resistant and highly epidemic Iberian MRSA did not replace the much less resistant pediatric clone during the 6 years of surveillance. The pediatric clone was also identified among contemporary MRSA isolates from Poland, Argentina, The United States, and Colombia, and the overwhelming majority of these were also associated with pediatric settings. We propose that the pediatric MRSA strain represents a formerly widely spread archaic clone which survived in some epidemiological settings with relatively limited antimicrobial pressure.

Anti-Bacterial Agents↗
PubMed1998

Atopy and enteroparasites.

UNLABELLED: There are not many studies about the intestinal parasitosis (IP) and atopic asthma (AA) relationship, and these show discordant results, possibly due to different studies design and differences in population selection. On the basis of personal results obtained by an epidemiological inquiry designed to estimate the prevalence of enteroparasitoses in asthmatic children and vice vesa, the aim of this study was to compare the prevalence of IP in AA and in a control group (CG) by a cross sectional study using clinical and laboratorial parameters, applied to 63 children (47 with AA and 16 in CG) aged 6 to 11 years, 37 males and 26 females, Caucasians, with the same socioeconomical conditions, consecutively selected in our Hospital. The results showed: The IP in AA children was 21.3%; the IP in CG was 25%; in the group with AA and IP, 40% of them had symptomology of IP; in the CG with IP, 100% had symptoms. CONCLUSIONS: The IP prevalence in AA was not statistically different from the IP in CG (p > 0.05) More data are needed to clarify the significant differences between the symptomatology rates of IP in asthmatic and non asthmatics; the reduced number of patients with symptoms in AA may reflect modulation of IP in AA and/or different parasite load.

Animals↗