A validação é essencial para definir se uma metodologia desenvolvida está completamente adequada aos objetivos a que se destina, a fim de se obter resultados confiáveis que possam ser satisfatoriamente interpretados. Além disso, pode ser considerada um dos principais instrumentos de garantia da qualidade. Foram avaliados os parâmetros de especificidade, seletividade, limite de quantificação, linearidade, intervalo, precisão (repetibilidade e precisão intermediária) e exatidão. A linearidade apresentou coeficiente de correlação igual a 0,99975 no intervalo de 2-8 µg/mL. Os excipientes contidos na formulação não são absorvidos no comprimento de onda utilizado, não interferindo assim na análise e quantificação da substância ativa. A quantificação de piroxicam em cápsulas de gelatina através de espectrofotometria UV no comprimento de 333 nm foi aprovada em todos os parâmetros analisados, sendo portanto, devidamente validada.Palavras-chave: validação de metodologia analítica; espectrofotometria ultravioleta; piroxicam. ABSTRACTThe validation is essential to define if a developed methodology is completely adjusted to the objectives that the one is destines, in order to get trustworthy results that can be satisfactorily interpreted. Moreover, it is considered one of the main instruments of quality control. The parameters used in the validation process were: specificity, selectivity, quantification limit, linearity, range, precision (repeatability and intermediate precision) and accuracy. The linearity in the range of 2-8 µg/mL presented a correlation coefficient of 0.99975. The excipients in the formulation did not interfere with the analysis and the recovery was quantitative. The quantification of piroxicam in gelatin capsules through UV spectrophotometry in the length of 333 nm was approved in all the analyzed parameters, being therefore, duly validated.

Perioperative hypothermia had detrimental effects on the healing of colonic anastomosis in rats.

PURPOSE:We evaluated the hypothesis that induced perioperative hypothermia (32 ± 1ºC) affects the redox balance in the tissue of colonic anastomosis in rats by modifying biochemical enzymatic and non-enzymatic markers related to oxidative stress. METHODS:Forty-eight male Wistar rats were randomly divided into eight experimental groups of six animals each and underwent laparotomy, sigmoid section and immediate anastomosis. Four groups were operated under normothermia (36 ± 1ºC), and the other four under hypothermia (32 ± 1ºC). The animals were reoperated on days 3, 7 and 14 postoperatively, and two groups underwent SHAM at 3 days. From the scar tissue samples, the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) was evaluated, and the levels of non-enzymatic markers of oxidative stress, such as reduced glutathione (GSH) and lipid peroxidation, were measured by the thiobarbituric acid reactive substances (TBARS) assay. The means were compared between groups corresponding to each day of sampling and euthanasia. RESULTS:The hypothermic groups showed a significant reduction on the activity of SOD on day 7 postoperatively, on the activity of CAT on days 7 and 14 postoperatively and on the levels of GSH on day 7 postoperatively. The level of lipid peroxidation was increased in the hypothermia group on day 7 postoperatively and decreased on day 14 compared with the normothermic groups. CONCLUSION:Perioperative hypothermia reduced the activity of the antioxidant enzymes catalase and superoxide dismutase, glutathione levels and increased lipid peroxidation in the scar tissue of colonic anastomoses in rats.

The ability of three related naturally occurring flavonols in inhibiting Hb oxidation and lipid peroxidation of human erythrocyte membranes was evaluated. The flavonols tested exhibited the following order of potency to inhibit tert‐butyl hydroperoxide‐induced Hb oxidation: quercetin > rutin > morin. The Hb oxidation was estimated by the extent of metHb and hemichrome formation induced by tert‐butyl hydroperoxide. Quercetin or rutin (0.5 mM) increased oxyHb levels about 33% and 10%, respectively. Morin (0.5 mM) was pro‐oxidant, decreasing the oxyHb about 7%. Despite the pro‐oxidant action on Hb oxidation, morin offered greater protection against lipid peroxidation than rutin, preventing the formation of TBA reactive substances by 33.1%, at 0.2 mM. However, quercetin (0.2 mM) provided approximately 50% protection against TBARS formation. The results show that the flavonoids tested are protective for Hb oxidation and lipid peroxidation on erythrocyte membrane subjected to oxidative stress. Quercetin in particular, may be useful in diminishing oxidative damage to red blood cells

Lactococcus lactis QMF 11, isolated from Brazilian fresh cheese, produces bacteriocin like inhibitory substances (bac+). To evaluate L. lactis QMF11 possible application on biopreservation systems of dairy food, co‐inoculation studies were performed in pasteurized milk (8 °C, 10 days) targeting the inhibition of Listeria monocytogenes ATCC 7644 or Staphylococcus aureus ATCC 25923. Lactobacillus sakei ATCC 15521 was used as a negative control for bacteriocin production (bac−). L. monocytogenes and S. aureus reached 8 log CFU ml−1 and 5.4 log CFU ml−1 in monoculture, respectively, compared to <2.3 log CFU ml−1 and 4.7 log CFU ml−1 in co‐culture with L. lactis QMF 11. Instead, in the presence of the bac−, L. monocytogenes population reached 7.3 log CFU ml−1 and S. aureus populations 5.5 log CFU ml−1. These results indicate that L. lactis QMF11 may have potential for be use as biopreservative culture in dairy products, mainly because of its antilisterial activity. Practical applications There is a renewed interest in the use protective bacterial cultures or their metabolites to guarantee the microbiological safety and to extend the shelf life of dairy products, in a process called biopreservation. The research in this area has been leveraged by consumers demand for naturally preserved foods. Dairy products are natural niches for Lactococcus lactis strains, and these bacteria have been associated with food production and preservation since ancient times. As a dominant species in dairy ecosystems, L. lactis strains are very interesting because they are not likely to require regulatory approval for practical application as bioprotective cultures.

Listeria monocytogenes é o agente causal da listeriose, uma doença de caráter oportunista e grave, que afeta especialmente gestantes, neonatos, idosos e imunodeprimidos. Os alimentos são os principais veículos de transmissão da bactéria, sendo considerados de alto risco especialmente os prontos para consumo, que apresentam longa vida de prateleira sob refrigeração e são consumidos sem aquecimento prévio, como é o caso de diversos derivados lácteos. O objetivo deste trabalho foi verificar a presença de L. monocytogenes em amostras queijo muçarela fatiado, adquiridas no comércio varejista de Goiânia (GO). 34 amostras do produto foram analisadas no Laboratório de Pesquisa em controle de Qualidade de Alimentos e Medicamentos da Faculdade de Farmácia da Universidade Federal de Goiás. As análises foram conduzidas de acordo com o protocolo preconizado pelo Food and Drug Administration. Os resultados foram confirmados com o kit API Listeria. A presença de L. monocytogenes foi detectada em quatro (11,75%) das 34 amostras de queijo muçarela avaliadas, e a presença de L. innocua em uma (2,9%) das amostras. Apesar de, no Brasil, ainda não ter sido possível estabelecer a relação entre alimentos e doença, os resultados do presente estudo evidenciam que o queijo muçarela fatiado pode atuar como importante veículo para transmissão da bactéria, constituindo, dessa forma, risco para os consumidores.

No abstract