Evaluation of pH, available chlorine content, and antibacterial activity of endodontic irrigants and their combinations against Enterococcus faecalis

Objectives. The objectives of this study were to evaluate pH, available chlorine content, and antibacterial activity of endodontic irrigants and their combinations.Study design. The pH and chlorine content of sodium hypochlorite (NaOCl) were analyzed pure and in combination with 10% citric acid (CA) and apple vinegar (AV). The antibacterial effect of the following solutions was measured by direct contact test against Enterococcus faecalis: 2.5% NaOCl, 2.5% NaOCl + 10% CA (7:3), 2.5% NaOCl + AV (5:5), 10% CA, and AV. Sterile saline was used as control. The colony-forming units were determined by serial decimal dilutions.Results. The combination of 2.5% NaOCl with CA or AV lowered the pH and the chlorine content. NaOCl, alone or in combination was able to eliminate E. faecalis in 30 seconds, and CA, after 10 minutes. AV promoted reduction (32.2%) after 10 minutes.Conclusions. NaOCl with acidic solutions lowered the pH and the chlorine content, but did not alter its antibacterial effect. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011; 112:132-135)

Determination of the maximum inhibitory dilution of cetylpyridinium chloride-based mouthwashes against Staphylococcus aureus: an in vitro study

The aim of this in vitro study was to determine the maximum inhibitory dilution (MID) of four cetylpyridinium chloride (CPC)based mouthwashes: CPC+Propolis, CPC+Malva, CPC+Eucaliptol+Jua+Roma+Propolis (Natural Honey (R)) and CPC (Cepacol (R)), against 28 Staphylococcus aureus field strains, using the agar dilution method. Decimal dilutions ranging from 1/10 to 1/655,360 were prepared and added to Mueller Hinton Agar. Strains were inoculated using Steers multipoint inoculator. The inocula were seeded onto the surface of the culture medium in Petri dishes containing different dilutions of the mouthwashes. The dishes were incubated at 37 degrees C for 24 h. For readings, the MID was considered as the maximum dilution of mouthwash still capable of inhibiting microbial growth. The obtained data showed that CPC+Propolis had antimicrobial activity against 27 strains at 1/320 dilution and against all 28 strains at 1/160 dilution, CPC+Malva inhibited the growth of all 28 strains at 1/320 dilution, CPC+Eucaliptol+Jua+Roma+Propolis inhibited the growth of 2 strains at 1/640 dilution and all 28 strains at 1/320 dilution, and Cepacol (R) showed antimicrobial activity against 3 strains at 1/320 dilution and against all 28 strains at 1/160 dilution. Data were submitted to Kruskal-Wallis test, showing that the MID of Cepacol (R) was lower than that determined for the other products (p<0.05). In conclusion, CPC-mouthwashes showed antimicrobial activity against S. aureus and the addition of other substances to CPC improved its antimicrobial effect.

Influence of artificial saliva in biofilm formation of Candida albicans in vitro

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Varenius e o conhecimento matemático do século XVII

Neste artigo, discutimos o contexto do desenvolvimento da Geografia que, no século XVII, liberou-se do seu papel nas diferentes fés cristãs, bem como a importância da cisão dos Protestantes, em Luteranos e Calvinistas, para o processo de secularização, e o conseguinte estabelecimento da Geografia como ciência moderna. Analisamos a contribuição fundamental do luterano Bernhard Varen, cuja obra Geografia Geral apresenta o paradigma dessa nova ciência. Naquela época, a Geografia era considerada um ramo da matemática, e esta obra nos dá indícios sobre notações e conceitos matemáticos utilizados naquele século. Analisamos, particularmente, o uso da notação decimal de números não inteiros e algumas aplicações de conceitos trigonométricos, comparando a edição original com as principais reedições desta obra.

Cinética de degradação do ácido ascórbico em ameixas liofilizadas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Quantificação de bactérias totais e esporuladas no solo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Use of homeopathic preparations in experimental studies with healthy plants

Background. The last comprehensive review of experimental research on effects of homeopathic treatments on plants was published in 1984, and lacked formal predefined criteria to assess study quality. Since then several new studies with more advanced methods have been published.Objectives: To compile a review of the literature on basic research in homeopathy with healthy plants with particular reference to studies investigating specific effects of homeopathic remedies.Methods: The literature search included English, French, German, Italian, Portuguese and Spanish publications from 1920 to April 2009, using predefined selection criteria. We included experiments with healthy whole plants, seeds, plant parts and cells. The outcomes had to be measured by established procedures and statistically evaluated. We developed a Manuscript Information Score (MIS) and included only publications which provided enough information for proper interpretation (MIS >= 5). A formallised Study Methods Evaluation Procedure (SMEP) was used to evaluate these studies, and the subgroup of studies with adequate controls to identify specific effects.Results: A total of 86 studies in 79 publications was identified, 43 studies included statistics, 29 had MIS >= 5, and 15 studies investigated the specificity of homeopathic preparations. Specific effects of decimal, centesimal and fifty millesimal potencies were found including dilution levels far beyond the Avogadro number. In consecutive series of potencies only some of the tested potencies showed effects. There were many individual studies with diverse methods and very few reproduction trials.Conclusions: Healthy plant models seem an useful approach to investigate basic research questions about the specificity of homeopathic preparations. More investigations with more advanced methods are recommended, especially in the sectors of potentisation techniques, effective potency levels and conditions for reproducibility. Systematic negative control experiments should become a routine procedure to control the stability of the experimental systems. Homeopathy (2009) 98, 228-243.

Survey of the Microbiological Quality of Nonalcoholic Carbonated Beverages

The number and the main groups of microorganisms present in samples of different nonalcoholic carbonated beverages (lemon, orange and guaraná soft drinks) obtained from a small factory were analyzed. The samples were obtained at the end of the processing line. They were then divided into two lots: one was sent to immediate analysis, the other was stored at environmental temperature for 90 d thereafter it was submitted to the same analysis. Aliquots of 1 mL were drawn from the various samples and the corresponding decimal dilutions were prepared. They were then grown in culture media and counts of mesophilic aerobic bacteria, molds and yeasts, acid-producing bacteria, total and fecal coliforms were taken. It was observed that, of all the analyzed samples, at time 0 or after storage sample C (orange) was the best, since it conformed to the microbiological standards established by legislation. The guaraná type could also be consumed on day zero; the lemon type was inadequate for consumption of all the analyzed samples, the orange type was the only one that could be consumed within 3 months of storage.

Número do tipo ponto flutuante com precisão estendida

Pós-graduação em Engenharia Mecânica - FEIS

Avaliação de operadores de algoritmos genéticos em otimização multidimensional

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo da utilização de medidas não-oficiais em uma comunidade de vocação rural

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Contribuições de um grupo de estudos para a formação matemática de professoras que lecionam nas séries iniciais

Pós-graduação em Educação Matemática - IGCE

Eficácia da irrigação ultrassônica passiva na limpeza e eliminação de Enterococcus faecalis dos canais radiculares

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

As ticas de matema dos índios Kalapalo: uma interpretação de estudos etnográficos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Representações dos números racionais e a medição de segmentos: possibilidades com tecnologias informáticas

Pós-graduação em Educação Matemática - IGCE