António Ramos

Bio: António Ramos is an academic researcher from University of Coimbra. The author has contributed to research in topics: Semicarbazide & Population. The author has an hindex of 2, co-authored 2 publications receiving 55 citations. Previous affiliations of António Ramos include University of Évora & University of Lisbon.

Impacte do aumento das taxas moderadoras na procura dos cuidados de saúde primários na USF do Parque

Abstract: Objectives: To assess the impact of the increase in user fees on the demand for primary health care in the Parque Family Health Unit, to compare consultation rates in the Parque FHU between January 1and May 31, 2011, and the same period in 2012, and to identify factors associated with patient demand for care in this unit. Design: Retrospective longitudinal, observational and analytical. Setting: Parque Family Health Unit, North Lisbon Health Centres Group (ACES Lisboa Norte) Population: Patients of the Parque Family Health Unit. Methods: A convenience sample of patients was selected from the health records of the Family Health Unit. The Student's t-test, Anova, Pearson correlation and Spearman correlation were used with statistical significance set at the 5% level. Results: We analyzed the records of 338 patients. The majority were female (n = 241; 71,3%), with a mean age of 57 years (standard deviation = 18,92). There was an increase in the consultation rate from 2011 to 2012. The mean number of visits was 0.87 (IC95% 0.623-1.129, p >= 0.01). Older patients, patients with more illnesses, and those taking daily medication had higher visiting rates (p >= 0.05). There were fewer visits made by patients with a higher monthly income (p >= 0.05). A positive correlation between the number of illnesses and the number of medical visits was observed in patients exempt from user fees. Conclusions: In 2012 the number of visits to the Health Unit increased. Advanced age, a larger number of illnesses and daily medication use were associated with a greater number of visits. Higher economic status was associated with lower visiting rates in both study periods. The increase in user fees did not have a negative impact on patient demand for primary health care in the Parque Family Health Unit.

Nitrofuran antibiotics: a review on the application, prohibition and residual analysis

Abstract: Nitrofuran antibiotics, employed for the treatment of bacterial diseases in livestock production, were banned from use in the European Union (EU) in 1995 due to concerns about the carcinogenicity of their residues in edible tissue. This review provides an overview of nitrofuran toxicity, metabolism, and also specific aspects of legislation surrounding their prohibition. Special attention is devoted to semicarbazide - a nitrofuran metabolite and food contaminant. Analytical procedures for nitrofuran analysis in various matrices and validation require - List of abbreviations AHD = 1-aminohydantoin; AOZ = 3-amino-2-oxazolidinone; AMOZ = 3-amino-5-morpholino-methyl-1,3-oxa- zolidinone; CC α = decision limit; CC β = detection capability; EC = European Commission; EFSA = European Food Safety Authority; ELISA = enzyme linked immuno-adsorbent assay; ESI = electro-spray ionisation; EU = European Union; FTD = furaltadone; FZD = furazolidone; HPLC = high performance liquid chromatography; IC = inhibition concentration; LC = liquid chromatography; LOD = limit of detection; MS = mass spectrometry; NFT = nitrofurantoin; NFZ = nitrofurazone; NP = nitrophenyl; NPAHD = 3-(2-nitrobenzylidenamino)-2,4-imi- dazolidinedione); NPAMOZ = 5-(morpholinomethyl)-3-(2-nitrobenzylidenamino)-2-oxazolidinone); NPAOZ = (3-(2-nitrobenzylidenamino)-2-oxazolidinone); NPSEM = 3((2-nitrophenyl)methylene)-hydrazinecarboxamide; o-NBA = ortho-nitrobenzaldehyde; RASFF = Rapid Alert System for Food and Feed; SE = solvent extraction; SEM = semicarbazide; SPE = solid phase extraction; UV = ultraviolet

Automated In-Injector Derivatization Combined with High-Performance Liquid Chromatography-Fluorescence Detection for the Determination of Semicarbazide in Fish and Bread Samples.

Abstract: Semicarbazide (1) is a widespread genotoxic food contaminant originating as a metabolic byproduct of the antibiotic nitrofurazone used in fish farming or as a thermal degradation product of the common flour additive azodicarbonamide. The goal of this study is to develop a simple and sensitive high-performance liquid chromatography coupled with fluorescence detection (HPLC-FLD) method for the detection of compound 1 in food products. In comparison to existing methods for the determination of compound 1, the reported method combining online precolumn derivatization and HPLC-FLD is less labor-intensive, produces higher sample throughput, and does not require the use of expensive analytical instruments. After validation of accuracy and precision, this method was applied to determine the amount of compound 1 in fish and bread samples. Comparative studies using an established liquid chromatography coupled with tandem mass spectrometry method did not yield systematically different results, indicating that the developed HPLC-FLD method is accurate and suitable for the determination of compound 1 in fish and bread samples.

Química do ensino médio técnico e Enem: uma comparação curricular

Abstract: O Exame Nacional do Ensino Medio (ENEM) e uma avaliacao constituida por uma redacao e por questoes de multipla escolha...

Facile Formation of a DNA Adduct of Semicarbazide on Reaction with Apurinic/Apyrimidinic Sites in DNA.

Abstract: Mutagenic semicarbazide (SEM) is a hydrazine-containing food contaminant found in a wide variety of foods. Despite decades of research, the toxicity of SEM remains incompletely understood. In this study, we demonstrate for the first time that SEM reacts rapidly with apurinic/apyrimidinic sites in an endogenous DNA lesion to form covalently bonded DNA adducts in vitro and in bacteria. Specifically, we performed high-performance liquid chromatography with high accuracy and tandem mass spectrometry to characterize the DNA adduct formed by reacting SEM with 2′-deoxyribose and single- and double-stranded oligonucleotides containing abasic sites under physiologically relevant conditions. By analyzing the reaction mixture at different time points, the reaction kinetics of SEM with DNA was also elucidated. Moreover, by using a highly sensitive and selective liquid chromatography–tandem mass spectrometry method, we show that SEM induces the dose-dependent formation of DNA adducts in Escherichia coli. The results f...

Quantitation of the DNA Adduct of Semicarbazide in Organs of Semicarbazide-Treated Rats by Isotope-Dilution Liquid Chromatography–Tandem Mass Spectrometry: A Comparative Study with the RNA Adduct

Abstract: Semicarbazide is a widespread food contaminant that is produced by multiple pathways. However, the toxicity of semicarbazide to human health remains unclear. Using a highly accurate and sensitive isotope-dilution liquid chromatography-tandem mass spectrometry method, we identified and quantitated in this study for the first time the DNA and RNA adduct of semicarbazide in DNA/RNA isolated from the internal organs of semicarbazide-exposed rats. The analysis revealed a dose-dependent formation of the adducts in the internal organs of the semicarbazide-dosed rats and with the highest adduct levels identified in the stomach and small intestine. Furthermore, results showed significantly higher levels of the RNA adduct (4.1-7.0 times) than that of the DNA adducts. By analyzing DNA/RNA samples isolated from rat organs in semicarbazide-dosed rats at different time points postdosing, the adduct stability in vivo was also investigated. These findings suggest that semicarbazide could have exerted its toxicity by affecting both the transcription and translation processes of the cell.