Effects of low-level laser therapy combined with toluidine blue on polysaccharides and biofilm of Streptococcus mutans.

The aim of this study was to evaluate the effect of a low-level laser therapy in combination with toluidine blue on polysaccharides and biofilm of Streptococcus mutans. S. mutans biofilms were formed on acrylic resin blocks. These biofilms were exposed eight times/day to 10 % sucrose, and two times/day, they were subjected to one of the following treatments: G1, 0.9 % NaCl as a negative control; G2, 0.12 % chlorhexidine digluconate (CHX) as a positive antibacterial control; and G3 and G4 antimicrobial photodynamic therapy (aPDT) combined with toluidine blue using dosages of 320 and 640 J/cm(2), respectively. The experiment was performed in triplicate. The biofilm formed on each block was collected for determination of the viable bacteria and concentration of insoluble extracellular polysaccharides (IEPS) and intracellular polysaccharides (IPS). CHX and aPDT treatments were able to inhibit bacterial growth in comparison with negative control (p < 0.05). The aPDT treatment reduced the number of viable bacteria formed in the S. mutans biofilm, in a dose-dependent manner (p < 0.05). The concentration of IEPS and IPS in the biofilms formed in presence of aPDT did not differ each other or in comparison to CHX (p > 0.05). The results suggest that low-level laser therapy presents effects on biofilm bacteria viability and in polysaccharides concentration.

[Aluminum content in individual components, used to prepare adult total parenteral nutrition mixtures in Argentine, and in comparison with international regulation]. / Contenido de aluminio en componentes individuales utilizados para preparar mezclas de nutrición parenteral en Argentina, y su comparación con la legislación internacional.

INTRODUCTION: Aluminum (Al) is a toxic element which may contaminate pharmaceutical products used as individual components to prepare total parenteral nutrition mixtures (TPN). OBJECTIVES: 1) to determine Al levels in the individual components used to prepare TPN mixtures; 2) to compare detected Al levels with those imposed by international regulations (FDA); 3) to calculate the total amount of Al administered to adult and children receiving those typical TPN mixtures. METHODS: Al was determined by Inductively Coupled Plasma- Atomic Emission Spectrometry (ICP-OES) (Perkin Elmer OPTIMA 5100 DV) in 44 individual products, from different labs and lots, belonging to 16 components available in Argentina: dextrose and amino acids for adult formulas and for pediatric formulas: lípids; potassium chloride; sodium chloride, magnesium sulfate; sodium phosphate; calcium gluconate; sodium glycerophosphate, zinc sulfate; multitrace elements; steril water (ampoules and great volume presentations). RESULTS: Al levels were detected in 43 of the 44 the studied components, except sterile water. The components of large volume presented between 249 y 1,580 µg Al/ L, between 4 and 180 times FDA established levels (25 µg Al/ L). Small volume components presented Al levels between 85 y 4,909 g/ L, not declared in labels. CONCLUSIONS: The highest amounts of Al were detected in calcium gluconate, sodium phosphate and multitrace elements. 2) Usually prescribed TPN mixtures would have higher Al levels than those accepted by FDA regulation; 3) The highest aluminum concentration was provided by dextrose, amino acids and lipids in adult TPN mixtures. In neonate TPN mixtures, Al highest amounts were provided by dextrose and calcium gluconate. The calculated concentration of Al in TPN mixtures was higher than those stipulated by international regulation (5 µg Al/kg (body weight)/ d). It would be advisable for manufacturers to declare the content of aluminum in the label, with the aim of avoiding toxicities which would compromise the critical patients' evolution.

Introducción: aluminio (Al) es un elemento tóxico que puede ser contaminante de productos farmacéuticos utilizados para preparar mezclas de nutrición parenteral (NP). Objetivos: 1) determinar la concentración de Al en componentes individuales utilizados para preparar mezclas de NP; 2) comparar las cantidades detectadas con los límites de la regulación internacional (FDA); 3) calcular la cantidad de Al administrada en fórmulas habituales de NP para neonatos, niños y adultos. Materiales y métodos: El Aluminio fue determinado por Espectroscopía de Emisión Atómica-Plasma-Inductivo de Argón (Perkin Elmer 5100 DV) en 44 productos comerciales, de diferentes laboratorios y lotes, correspondientes a 16 componentes individuales: dextrosa; aminoácidos para adultos y pediátricos; lípidos; cloruro de potasio; cloruro de sodio, sulfato de magnesio; fosfato de sodio; gluconato de calcio; glicerofosfato de sodio; sulfato de zinc; elementos multitraza; agua estéril en ampollas y de gran volumen. Resultados: Todos los componentes de gran volumen, excepto el agua, contenían entre 249 y 1.580 µg/L, superando entre 4 y 180 veces mas que los niveles establecidos por la FDA (25 µg/L). Los componentes de pequeño volumen contenían entre 85 y 4.909 µg/L, no declarados en los rótulos. Conclusiones: 1) La mayor cantidad de aluminio se encontró en el gluconato de calcio, fosfato de sodio y elementos multitraza. 2) Las mezclas de uso habitual para NP presentan niveles de Al mayores al límite de FDA. Los componentes que aportan mayor cantidad de aluminio en las mezclas de NP para adultos son: glucosa, aminoácidos y lípidos, pero en las de neonatos, el mayor aporte proviene de la dextrosa y gluconato de calcio. 3) En las mezclas de NP para neonatos, niños y adultos la cantidad de aluminio administrado por kg de peso supera la recomendación de FDA (5 µg/kg de peso /día). Los productos comerciales deberían declarar el contenido de Al para no comprometer la evolución de los pacientes graves.

Cloning and characterization of Echinococcus granulosus (Cestode) EgactI and EgactII actin gene promoters and their functional analysis in the NIH3T3 mouse cell line

We report here for the first time the structure and function of a promoter from a cestode. The ability of DNA fragments respectively encompassing the 935-bp and 524-bp regions upstream from the ATG codon from the EgactI and EgactII actin genes of Echinococcus granulosus to promote transcription was studied in the NIH3T3 mouse cell line. The results of transfection assays showed that both regions have strong promoter activity in these cells. The fragments were tested in both orientations and the 524-bp fragment of EgactII presented a bidirectional promoter activity. Deletion analysis of EgactI and EgactII promoters indicated the presence of regulatory regions containing putative silencer elements. These results indicate that both EgactI and EgactII promoters are functional and that the preliminary functional evaluation of E. granulosus and possibly of other cestode promoters can be performed in heterologous cell lines

Cloning and characterization of Echinococcus granulosus (Cestode) EgactI and EgactII actin gene promoters and their functional analysis in the NIH3T3 mouse cell line.

We report here for the first time the structure and function of a promoter from a cestode. The ability of DNA fragments respectively encompassing the 935-bp and 524-bp regions upstream from the ATG codon from the EgactI and EgactII actin genes of Echinococcus granulosus to promote transcription was studied in the NIH3T3 mouse cell line. The results of transfection assays showed that both regions have strong promoter activity in these cells. The fragments were tested in both orientations and the 524-bp fragment of EgactII presented a bidirectional promoter activity. Deletion analysis of EgactI and EgactII promoters indicated the presence of regulatory regions containing putative silencer elements. These results indicate that both EgactI and EgactII promoters are functional and that the preliminary functional evaluation of E. granulosus and possibly of other cestode promoters can be performed in heterologous cell lines.