O efeito do ácido ascórbico tópico na cicatrização cutânea / The effect of topical ascorbic acid on cutaneous healing

Introdução: A ferida cirúrgica apresenta altos níveis de radicais livres em resposta ao dano cutâneo, o que gera a hipótese de um possível benefício do uso de antioxidantes no reparo destas feridas, tal como a aplicação tópica do ácido ascórbico. No entanto, pesquisas recentes obtiveram conclusões discrepantes para este tipo de tratamento. O objetivo é avaliar o efeito do ácido ascórbico tópico na cicatrização cutânea por meio de uma revisão de escopo. Métodos: A revisão de escopo foi realizada na base de dados Medline, Lilacs e Cochrane, com os descritores: ácido ascórbico, creme para a pele e cicatrização de feridas. Foram definidos como critérios de inclusão: ensaios clínicos randomizados, observacionais e revisões sistemáticas, em humanos, com data de publicação de até 5 anos, nas línguas inglesa, portuguesa ou espanhola. Foram excluídas: revisões narrativas, dissertações, teses, editoriais, estudos in vitro e em animais. Por fim, foi realizada a classificação dos estudos através da metodologia GRADE. Resultados: Foram encontrados 83 estudos e, após triagem, seis artigos foram selecionados. Destacou-se o uso do ácido ascórbico na concentração de 5 a 20% e de seus derivados (0,075% a 9,55%). Apresentaram a qualidade GRADE moderada os desfechos: aumento da firmeza cutânea e redução da vermelhidão, e alta qualidade: melhora na hidratação, elasticidade, colorometria das manchas e melhora do fechamento das feridas. Conclusão: O ácido ascórbico promove melhor elasticidade cutânea, diminuição do eritema e melhor fechamento das feridas. Apesar destes fortes indícios, ensaios clínicos randomizados com menor risco de viés de aferição e com maior casuística ainda se fazem necessários.

Introduction: The surgical wound has high levels of free radicals in response to skin damage, which raises the hypothesis of a possible benefit from using antioxidants in repairing these wounds, such as the topical application of ascorbic acid. However, recent research has found conflicting conclusions about this type of treatment. The objective is to evaluate the effect of topical ascorbic acid on skin healing through a scope review. Methods: The scope review was carried out in the Medline, Lilacs and Cochrane databases, with the descriptors: ascorbic acid, skin cream, and wound healing. Inclusion criteria were defined as randomized clinical trials, observational and systematic reviews, in humans, with a publication date of up to 5 years, in English, Portuguese or Spanish. The following were excluded: narrative reviews, dissertations, theses, editorials, in vitro and animal studies. Finally, the studies were classified using the GRADE methodology. Results: 83 studies were found, and six articles were selected after screening. The use of ascorbic acid in the concentration of 5 to 20% and its derivatives (0.075% to 9.55%) stood out. The outcomes presented a moderate GRADE quality: increased skin firmness and reduced redness, and high quality: improved hydration, elasticity, colorimetry of the stains and improved wound closure. Conclusion: Ascorbic acid promotes better skin elasticity, reduced erythema and better wound closure. Despite these strong indications, randomized clinical trials with a lower risk of measurement bias and greater casuistry are still necessary.

Etched fiber Bragg grating probe using a regular CNC machine and a 3D printer.

Etched fiber Bragg gratings (EFBGs) have been widely employed for refractive index (RI) measurements that can be used to monitor sugar consumption during the fermentation of alcoholic beverages. EFBGs are obtained by removing the cladding of a fiber Bragg grating, which is traditionally performed by a chemical attack with hydrogen fluoride, an extremely hazardous corrosive substance that causes severe wounds and even death. To overcome such drawbacks, this technical note presents a simple, practical, and low cost method for the diameter reduction of single mode optical fibers by mechanical polishing, employing a small scale computer numerical control device and an ad hoc 3D-printed rod. The sensor probe obtained was tested using sucrose aqueous solutions with RIs between 1.333 and 1.394, measured in an Abbe refractometer. The results show a linear shift of the Bragg wavelength with respect to RI with a correlation of 0.928.

Evaluation of craft beers through the direct determination of amino acids by capillary electrophoresis and principal component analysis.

The composition of beer wort in terms of amino acid (AA) content affects the final product quality, once it is related to the vitality of yeast during the initial exponential growth phase and throughout fermentation. The objective of this work was the use of a capillary zone electrophoresis method with UV-vis detection in association with Principal Component (Data) Analysis for craft beer classification. Cysteine, histidine, phenylalanine, lysine, tryptophan and arginine were the monitored AAs in wort and finished beer, which were extracted through cation exchange resin. Good differentiation among samples according to their production was obtained, showing a profile of AAs (

Occurrence of ESBL-producing Escherichia coli in soils subjected to livestock grazing in Azores archipelago: an environment-health pollution issue?

Antibiotics are successful drugs used in human and animal therapy; however, they must be considered as environmental pollutants. This study aims to isolate and characterize the extended-spectrum ß-lactamase (ESBL) producing Escherichia coli soil from Azores Archipelago subjected to livestock agricultural practices. Twenty-four soil samples were collected from three different pasture systems with different number of cattle heads, and from a control site. Antibiotic susceptibility method was performed by Kirby-Bauer disk diffusion method against 16 antibiotics, and the presence of genes encoding lactamases, antimicrobial resistance genes, virulence factors, and phylogenetic groups was determined by polymerase chain reaction (PCR). Nine ESBLs were recovered from the three grazing sites, and all isolates presented the beta-lactamase genes blaCTX-M-3 and blaSHV. E. coli isolates were resistance to tetracycline and streptomycin and harbored the tetB, strA, and strB genes. One isolate also showed resistance to sulfonamides, and the genes sul1 and sul2 were detected. The isolates were grouped into the following phylogenic groups: B1 (n = 6), D (n = 2), and A (n = 1). The presence of antibiotics and resistance genes in soils may be the source to the development of antimicrobial resistance, which may have negative consequences in human and animal health.

Genetic Characterization of vanA-Enterococcus faecium Isolates from Wild Red-Legged Partridges in Portugal.

Vancomycin-resistant enterococci (VRE) have been detected in wild animals representing a public health concern. The red-legged partridge (Alectoris rufa) is a common game bird and its meat is consumed in several countries, including Portugal. Three hundred five fecal samples of red-legged partridge from the north of Portugal were screened for VRE. Samples were cultured on Slanetz-Bartley agar supplemented with vancomycin (4 mg/L) and six vanA-Enterococcus faecium were recovered. Isolates were tested for antibiotic resistance and virulence genes. Multilocus sequence typing (MLST) was performed to study the genotypic diversity of vanA-containing E. faecium. The six isolates showed erythromycin resistance and harbored the erm(B) gene and the four that were tetracycline resistant showed the tet(M) gene. The C-terminal region of the pbp5 gene of the ampicillin-resistant isolates (minimal inhibitory concentration range of 256 µg/ml) was sequenced. Two different pbp5 alleles were detected when considering the changes of amino acid in 461-629 region. All isolates harbored the esp gene, whereas hyl, together with the esp gene, was detected in five isolates. MLST analysis grouped the isolates as ST448 (n = 1), ST139 (n = 1), and ST18 (n = 4). Our findings show that the red-legged partridges could be a reservoir of antimicrobial resistance genes and may contribute to the dissemination and transference of the resistance genes to other animals and humans.

Influence of treatment with quercetin on lipid parameters and oxidative stress of pregnant diabetic rats.

Among the numerous coadjuvant therapies that could influence the incidence and progression of diabetic complications, antioxidants and flavonoids are currently being tested in clinical trials. We investigated the effect of quercetin on biochemical parameters in streptozotocin-induced (60 mg/kg body mass, by intraperitoneal injection) diabetic rats. A total of 32 female Wistar rats were distributed among 4 groups as follows: control (G1); control treated with quercetin (G2); diabetic (G3); and diabetic treated with quercetin (G4). Quercetin administered to pregnant diabetic rats controlled dyslipidemia and improved lipid profiles in diabetes mellitus, regulated oxidative stress by reducing the generation of lipid hydroperoxides, and increased the activity of the antioxidant enzyme glutathione peroxidase.

Cardiomiopatia hipertrófica e gravidez / Hypertrophic cardiomyophaty and pregnancy

A cardiomiopatia hipertrófica (CMH) é doença incomum na gestação, caracterizada pela hipertrofia do ventrículo esquerdo, com expressão fenotípica e manifestações clínicas variáveis. O diagnóstico pode ser confirmado pelo ecocardiograma com Doppler. Trata-se de enfermidade bem tolerada na gestação, entretanto, pode desencadear insuficiência cardíaca congestiva, com grave comprometimento materno e perinatal. O tratamento para a gestante com CMH depende da obstrução do fluxo do ventrículo esquerdo. Em paciente sintomática portadora da forma obstrutiva, devem-se evitar grandes perdas sanguíneas e uso de drogas vasodilatadoras durante o trabalho de parto. O parto vaginal mostrou-se seguro, mas o período expulsivo deve ser abreviado com uso de fórceps naquelas que apresentam sintomatologia obstrutiva. Raras complicações podem acontecer, o que requer planejamento do parto e adequada monitorização materna e fetal. (AU)

The Hypertrophic Cardiomyopathy (HCM) is an uncommon condition during pregnancy, which attends with a left ventricular hypertrophy, and phenotypic expression and clinical are both variable. The diagnosis can be confirmed by Doppler echocardiography. Several studies show that it is a disease well tolerate during pregnancy, however it may trigger congestive heart failure with severe maternal and perinatal commitment. The treatment of pregnant patients with HCM depends on the presence of symptoms caused by obstruction of the left ventricle. In symptomatic patient carrying the obstructive form should be avoided large blood loss and use of vasodilator drugs during labor. Vaginal delivery is safe, but the expulsive period should be abbreviated with the use of forceps in those with obstructive symptoms. Rare complications can occur and therefore it is necessary a delivery planning and an adequate maternal and fetal monitoring. (AU)

Ciência e filosofia da ciência / Science and philosophy of science

A ciência consiste em um modo de conhecimento, que tende a formular, mediante uma linguagem rigorosa e apropriada, leis que regem os fenômenos. Fazer ciência é tentar compreender o mundo real no seu dinamismo de constituiçäo, enquanto como tal. Nesta tentativa, ele utiliza o método científico, que tem cinco fases; observaçäo do fenômeno, teorizaçäo, formulaçäo de hipótese, experimentaçäo e formulaçäo da lei. A filosofia da ciência discute o lugar da ciência dentro do contexto da humanidade, sua justificativa, seus métodos e premissas e sua evoluçäo. O estudo destes temas permite ao cientista compreender melhor o seu trabalho e os pressupostos básicos em que sua pesquisa se assenta

Filosofia e ciência: que é filosofar? / Philosophy and science: what is to philosophise?

O artigo procura esclarecer os conceitos de filosofia e do ato de filosofar, estabelecendo ligaçöes entre esta e as Ciências. Para os autores o filosofar näo se retringe apenas a complexas elucubraçöes metafísicas e a elaboraçäo de grandes sistemas filosóficos, mas inclui a atividade do médico e do cientista, ao estudar os fenômenos da vida, procurando entender o seu dinamismo e ao estabelecer diagnósticos e terapêuticas