Effect of restorative timing on shear bond strength of composite resin/calcium silicate-based cements adhesive interfaces.

OBJECTIVES: The aim of this study was to evaluate the shear bond strength inherent to immediate and delayed definitive composite resin restorations, over three different biomaterials. METHODS: Fifty-four aluminum blocks were randomly assigned to six experimental groups (n = 9) according to the biomaterial (Biodentine, TotalFill BC Putty, or PCM) and restoration timing (immediate or 7 days delayed). Regarding the restorative procedures, a two-step self-etch bonding system (Clearfil SE Bond) was applied and subsequently restored using a flowable composite resin (SDR). After shear bond strength testing, fracture pattern analysis was performed. The significance level was set at α = 0.05. RESULTS: Within the immediate groups, Biodentine showed the highest mean shear bond strength value, with no statistically significant differences (P > 0.05) being detected when compared with both TotalFill (P = 0.072) and PCM (P = 0.232) groups. Regarding the delayed restoration groups, Biodentine and TotalFill presented the highest mean shear bond strength value, with statistical differences when compared with PCM (P = 0.002 and P = 0.043, respectively). No statistically significant differences (P > 0.05) were verified between both immediate and delayed groups for each tested biomaterial. Also, a statistically significant association was found between the fracture type and the biomaterial (P < 0.001). CONCLUSIONS AND CLINICAL RELEVANCE: Our findings suggest that all tested biomaterials present suitable alternatives which allow to perform restorative procedures immediately after pulp capping biomaterial placement (3 or 12 min, depending on the bioactive cement), therefore requiring one single appointment to complete the procedure. Biodentine and TotalFill BC Putty have shown superior shear bond strength results when compared with PCM, within a delayed timeframe (7 days).

Infusion time for fish oil-containing parenteral emulsions in surgery: A study on ω-3 fatty acid dynamics in rats.

OBJECTIVES: The aim of this study was to contribute to the design of specialized parenteral nutrition protocols in surgery by evaluating the dynamics of polyunsaturated fatty acid (PUFA) concentrations in different body pools after the infusion of fish oil-containing lipid emulsion (FOLE) in rats that had undergone surgical central venous catheterization (CVC). METHODS: After 5-d adaptation in metabolic cages, 78 male Lewis rats (300-450 g) fed a standard diet were sacrificed (baseline control) or had only CVC (surgical control) or also received a 72-h infusion of a parenteral lipid emulsion with or without fish oil. The catheterized animals were sacrificed 0 (T0), 2 (T2), 6 (T6), and 12 h (T12) after the infusion ended. Gas chromatography was used to determine the concentrations of eicosapentaenoic (EPA), docosahexaenoic (DHA), and arachidonic (ARA) acids and the ω-3 to ω-6 ratio in plasma, liver, and blood leukocytes. Kruskal-Wallis and Wilcoxon tests were applied to plasma and liver data and descriptive analysis to leukocyte data. RESULTS: Plasma, liver, and leukocytes exhibited almost undetectable EPA and DHA and detectable ARA concentrations at baseline. Immediately after FOLE infusion (T0), these PUFAs changed in all pools, resulting in a higher ratio of ω-3 to ω-6 compared with rats with no FOLE infusion (P < 0.05). All these changes decreased over time, with residual effects remaining until T6 in plasma, T12 in liver, and only until T2 in leukocytes. CONCLUSION: Data from this study suggest that ω-3 PUFAs are cleared early after the end of FOLE infusion, mainly in leukocytes. This should be considered when FOLEs are applied for immunomodulatory purposes in surgery.

Is There an Advantage in Enriching Parenteral Lipid Emulsions Containing Fatty Acids From Fish Oil With Medium-Chain Triglycerides? A Study on Body Pool Concentrations of ω-3 Fatty Acids in Lewis Rats.

BACKGROUND: The addition of medium-chain triglycerides (MCTs) into parenteral lipid emulsions rich in fatty acids from fish oil (FOLEs) has been shown to improve their clearance and extrahepatic uptake. We assessed whether this effect could favor the leukocyte uptake of ω-3 polyunsaturated fatty acids (PUFAs) for immunomodulatory purposes METHODS: Following 5-day adaptation in metabolic cages, 42 male Lewis rats fed with AIN-93M chow were killed (baseline control group [BC]) or submitted to central venous catheterization and distributed into (1) surgical control group without parenteral infusion (chow group), (2) test emulsion (MCT/LCT/FO) group with the parenteral infusion of a FOLE containing 40% MCT, and (3) control emulsion group (LCT/FO) with the parenteral infusion of an FOLE without MCT. The 2 FOLEs had similar ω-3 PUFA contents and ω-6/ω-3 PUFA ratios and were infused during 48 and 72 hours. Concentrations of ω-3 and ω-6 PUFAs in plasma, liver, and blood mononuclear and polymorphonuclear leukocytes were assessed by gas chromatography RESULTS: In both FOLE groups, leukocyte concentrations of ω-3 PUFAs peaked after 48 hours' infusion (vs BC). At this time point, plasma concentrations of ω-3 PUFAs were higher in MCT/LCT/FO group than in LCT/FO group and the opposite was found in the liver (P<.05), but no differences in PUFA concentrations were observed between these groups in leukocytes (P>.05) CONCLUSION: The ω-3 PUFAs provided by FOLEs rich in MCT were less incorporated by liver and remained more available for extrahepatic cell delivery, but this did not result in a clear benefit in increasing their incorporation by peripheral leukocytes.

Human xanthine oxidase recombinant in E. coli: A whole cell catalyst for preparative drug metabolite synthesis.

Human xanthine oxidoreductase (XOR), which is responsible for the final steps of the purine metabolism pathway and involved in oxidative drug metabolism, was successfully expressed in Escherichia coli BL21(DE3) Gold. Recombinant human (rh) XOR yielded higher productivity with the gene sequence optimized for expression in E.coli than with the native gene sequence. Induction of XOR expression with lactose or IPTG resulted in complete loss of activity whereas shake flasks cultures using media rather poor in nutrients resulted in functional XOR expression in the stationary phase. LB medium was used for a 25L fermentation in fed-batch mode, which led to a 5 fold increase of the enzyme productivity when compared to cultivation in shake flasks. Quinazoline was used as a substrate on the semi-preparative scale using an optimized whole cell biotransformation protocol, yielding 73mg of the isolated product, 4-quinazolinone, from 104mg of starting material.

Zoonoses parasitárias / Parasitic zoonosis

O contado dos animais de estimaçäo, como cäes e gatos, torna-se cada dia mais frequênte e mais próximo. Esse contato traz preocupaçöes como os riscos envolvidos e as zoonoses parasitárias. O presente artigo visa a esclarecer sobre as zoonoses parasitárias mais freqüentes nos centros urbanos, a larva migrans visceral e a larva migrans cutânea, para que desta forma o médico possa esclarecer seu paciente e, sobretudo, orientá-lo das medidas profiláticas para wque o contato entre o homen e seus animais de estimaçäo näo seja abalado.(au)

Análise crítica do uso de esteróides no período neonatal / Critical analysis of the use of corticosteroids in the neonatal period

Objetivo: rever o uso terapêutico de esteroides no que diz respeito ao recém-nascido. Métodos: revisão de literatura. Especificamente discutimos a literatura mundial relacionada ao uso de corticosteróides na doença pulmonar crônica, insuficiência adrenal e edema daas vias aéreas superiores. Conclusões: apesar dos dados da literatura comprovando uma melhora do quadro clínico de doença pulmonar crônica em curto prazo,não se mostrou diminuição da mortalidade ou morbidade de recém-nascidos tratados com dexametasona. Dada a evidências recente de que o uso dessas drogas em recém-nascidos pode levar a efeitos maléficos irreversíveis no sistema nervoso e no desenvolvimento neurológico, o seu uso indiscriminado deve ser reconsiderado. A indicação clínica do uso de corticosteróides deve se limitar a casos severos de doença pulmonar crônica ou hipotensão arterial recalcificante ao uso de agentes vasopressores

Controle de qualidade de misturas de ácidos aminados, hidratos de carbono e emulsäo de lipídios para uso parenteral (3 em 1) / The control of the stability of the amino acids, carbohydrates and lipids, mixtures in the same solution (3x1 system) in parenteral nutrition

O trabalhos consiste na avaliaçäo dos lipossomas, através da microscopia eletrônica, nas misturas nutritivas de ácidos aminados a 10 por cento, com glicose nas concentraçöes de 10, 20 e 25 por cento e adiçäo final de emulsäo lipídica a 10 por cento (TCL) na proporçäo de uma parte desta para cada duas pates da Nutriçäo Parenteral. A emulsäo pura e as soluçöes foram analisadas nos tempos 0/12/24/48 e 72 horas após o preparo, à temperatura ambiente e em estoque sob refrigeraçäo. Concluíram que os lipossomas näo se alteraram morfologicamente e näo sofreram coalisäo mesmo nas concentraçöes de 25 por cento de HC e no tempo de até 72 h à temperatura ambiente

Estudo à microscopia eletrônica da estabilidade física das emulsões lipídicas em soluções nutritivas parenterais / Electron microscopy study of the physical stability of lipid emulsions in parenteral nutrient solutions

O estudo consiste na determinação da estabilidade dos lipossomas das ELs utilizadas como fonte calórica em 28 composições de NPTs, denominadas misturas 3 em 1, através da avaliação à microscopia eletrônica de transmissão. Foram verificadas a ocorrência ou não de instabilidade como floculação/agregação ou coalescência/aglutinação das partículas e medidos os respectivos maiores diâmetros encontrados, sendo estudadas as ELs originais e as formulações mais comuns em nossa prática clínica, nos tempos, 0, 24, 48 e 72h. Foram avaliados e calculados alguns dos fatores predisponentes e de favorecimento de instabilidade como dosagem de pH, valores de CAN (número de agregação crítica) e avaliação farmacêutica dos insumos adicionados. Os resultados encontrados foram 5 formulações com ELs estáveis, 16 com floculação e 7 com coalescência. Para as amostras com floculação, o fator de maior contribuição foi a diminuição do pH, interferindo nas forças eletrostáticas. Para coalescência, a instabilidade ocorreu supostamente pela alteração do pH, pela adição de heparina e cátions divalentes em concentrações elevadas. Como conclusão, os lipossomas não alteram-se morfologicamente quando a sequência de manipulação das formulações encontra-se em condições controladas,são analisadas farmaceuticamente, apresentam os componentes em concentrações e ordem de adição adequadas e quando o tempo e a temperatura após preparação forem os recomendados. O uso clínico da mistura 3 em 1 deve ser limitado aos parâmetros sugeridos.