Rhodosporidium toruloides cultivated in NaCl-enriched glucose-based media: adaptation dynamics and lipid production

In the present report and for the first time in the international literature, the impact of the addition of NaCl upon growth and lipid production on the oleaginous yeast Rhodosporidium toruloides was studied. Moreover, equally for first time, lipid production by R. toruloides was performed under non-aseptic conditions. Therefore, the potentiality of R. toruloides DSM 4444 to produce lipid in media containing several initial concentrations of NaCl with glucose employed as carbon source was studied. Preliminary batch-flask trials with increasing amounts of NaCl revealed the tolerance of the strain against NaCl content up to 6.0% (w/v). However, 4.0% (w/v) of NaCl stimulated lipid accumulation for this strain, by enhancing lipid production up to 71.3% (w/w) per dry cell weight. The same amount of NaCl was employed in pasteurized batch-flask cultures in order to investigate the role of the salt as bacterial inhibiting agent. The combination of NaCl and high glucose concentrations was found to satisfactorily suppress bacterial contamination of R. toruloides cultures under these conditions. Batch-bioreactor trials of the yeast in the same media with high glucose content (up to 150 g/L) resulted in satisfactory substrate assimilation, with almost linear kinetic profile for lipid production, regardless of the initial glucose concentration imposed. Finally, fed-batch bioreactor cultures led to the production of 37.2 g/L of biomass, accompanied by 64.5% (w/w) of lipid yield. Lipid yield per unit of glucose consumed received the very satisfactory value of 0.21 g/g, a value amongst the highest ones in the literature. The yeast lipid produced contained mainly oleic acid and to lesser extent palmitic and stearic acids, thus constituting a perfect starting material for “second generation” biodiesel

Matrix Metalloproteinase Expression in Teeth with Apical Periodontitis Is Differentially Modulated by the Modality of Root Canal Treatment

Introduction: The objective of this study was to investigate the expression of matrix metalloproteinases (MM Ps) in apical periodontitis and during the periapical healing phase after root canal treatment. Methods: Apical periodontitis was induced in dog teeth, and root canal treatment was performed in a single visit or by using an additional calcium hydroxide root canal dressing. One hundred eighty days after treatment the presence of inflammation was examined, and tissues were stained to detect bacteria. Bacterial status was correlated to the degree of tissue organization, and to further investigate molecules involved in this process, tissues were stained for MMP-1, MMP-2, MMP-8, and MMP-9. Data were analyzed by using one-way analysis of variance followed by Tukey test or Kruskal-Wallis followed by Dunn test. Results: Teeth with apical periodontitis that had root canal therapy performed in a single visit presented an intense inflammatory cell infiltrate. Periapical tissue was extremely disorganized, and this was correlated with the presence of bacteria. Higher MMP expression was evident, similar to teeth with untreated apical periodontitis. In contrast, teeth with apical periodontitis submitted to root canal treatment with calcium hydroxide presented a lower inflammatory cell infiltrate. This group had moderately organized connective tissue, lower prevalence of bacteria, and lower number of MMP-positive cells, similar to healthy teeth submitted to treatment. Conclusions: Teeth treated with calcium hydroxide root canal dressing exhibited a lower percentage of bacterial contamination, a lower MMP expression, and a more organized extracellular matrix, unlike those treated in a single visit. This suggests that calcium hydroxide might be beneficial in tissue repair processes. (J Endod 2010;36:231-237)

Use of the checkerboard DNA-DNA hybridisation technique for in vivo detection of cariogenic microorganisms on metallic brackets, with or without use of an antimicrobial agent

Objective: Using checkerboard DNA-DNA hybridisation (CDDH) assay, this randomised clinical study evaluated the contamination of metallic brackets by four cariogenic bacterial strains (Streptococcus mutans, Streptococcus sobrinus, Lactobacillus casei and Lactobacillus acidophilus) and the efficacy of 0.12% chlorhexidine gluconate (CHX) mouthwashes in reducing bacterial contamination. Methods: Thirty-nine 11-33-year-old patients under treatment with fixed orthodontic appliances were enrolled in the study and had 2 new metallic brackets bonded to premolars. Nineteen patients used a 0.12% CHX mouthwash (Periogard (R)) and 20 patients used a placebo mouthwash (control) twice a week. After 30 days, the brackets were removed and samples were obtained for analysis by CDDH. Data were analysed statistically by the Kruskal-Wallis test (alpha = 0.05) using the SAS software. Results: S. mutans, S. sobrinus, L. casei and L. acidophilus were detected in 100% of the samples from both groups. However, brackets of the control group were more heavily contaminated by S. mutans and S. sobrinus (P < 0.01). In the experimental group, although all counts decreased after rinsing with the chlorhexidine solution, there was significant difference only for S. mutans (P = 0.03). Conclusions: The use of 0.12% chlorhexidine gluconate mouthwashes can be useful in clinical practice to reduce the levels of cariogenic microorganisms in patients under treatment with fixed orthodontic appliances. (C) 2011 Elsevier Ltd. All rights reserved.

Integração vertical versus horizontal: oportunidades nas cadeias de suprimentos de garrafas PET das indústrias de refrigerantes e águas minerais do Estado do Rio de Janeiro

O objetivo do estudo aqui proposto é municiar os dirigentes e acionistas do segmento industrial de refrigerantes e águas minerais do Estado do Rio de Janeiro, com conhecimentos que possam lhes oferecer novas oportunidades de negócios e auxiliá-los na decisão pela integração horizontal ou vertical na cadeia de suprimentos de embalagens PET e de outros materiais plásticos na área produtiva de suas fábricas. Para tanto, foi realizada uma pesquisa com coleta de dados por meio de bibliografia e questionário aplicado a 28 empresas. O estudo contribui para o aumento da competitividade do segmento, apresentando resultados baseados em aspectos tecnológicos, econômicos, estratégicos, sociais e de meio ambiente. As conclusões mostram que há oportunidades para melhorias na cadeia industrial de embalagens PET e de outros materiais plásticos no segmento de refrigerantes e águas minerais no Estado do Rio de Janeiro, dentro do conceito de desenvolvimento sustentável.

Poder poluente de águas residuárias de suinocultura após utilização de um tratamento integrado

Em experimento de campo, avaliou-se o potencial de impacto ambiental de águas residuárias de suinocultura, acondicionadas em um tanque de estocagem, com distintos tempos de retenção hidráulica e aplicadas, posteriormente, em lisímetros preenchidos com solos arenosos, argilosos e de texturas médias. Para tal, foram determinados os valores de pH nos solos e as quantificações das concentrações de zinco e cobre na água residuária in natura e, após os quatro tempos de retenção hidráulica do tanque de estocagem, nos percolados dos lisímetros e nos solos. Os resultados mostram que a estocagem não foi eficiente na redução, aos níveis exigidos pela legislação, das concentrações de zinco e cobre nos efluentes do tanque de estocagem. A aplicação no solo gerou reduções eficientes nas concentrações de zinco e cobre. Por fim, enfocando a contribuição fertilizante destas águas residuárias, o solo argiloso foi o mais beneficiado com este sistema integrado de tratamento, contribuindo para a redução das concentrações de zinco e cobre para valores abaixo dos permitidos pelas legislações, o que protegeria o lençol freático da contaminação por esses dois metais pesados.

Aspectos clínicos, ultra-sonográficos e venográficos da tromboflebite jugular experimental em equinos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The influence of daily application of fluoride products on subsurface bovine enamel lesions stored in saliva substitutes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A pH optode based on thymol blue: application to determination of CO2 using flow injection analysis system

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

Salmonella spp. em carcaças, carne mecanicamente separada, lingüiças e cortes comerciais de frango

Alimentos de origem animal representam papel fundamental na epidemiologia das salmoneloses humanas. Apesar dos avanços tecnológicos, a carne de frango ainda é passível de contaminação bacteriana, especialmente por microrganismos do gênero Salmonella, que podem encontrar-se albergados no trato intestinal ou em outra parte do corpo das aves. O presente trabalho objetivou pesquisar a ocorrência de Salmonella em carne de frango e derivados procedentes da região Nordeste do Estado de São Paulo. Foram analisadas, através do método convencional de cultivo, 45 amostras de carcaças, 60 de carne mecanicamente separada (CMS), 25 de lingüiça de frango, 20 de peito, e 15 de coxa e sobre-coxa. Salmonella spp. foi encontrada em 13,3% (6/45) das carcaças, 25% (15/60) das amostras de CMS, 16% (4/25) das lingüiças, 30% (6/20) dos peitos e 13,3% (2/15) das coxas e sobre-coxas analisadas. do total de 165 amostras analisadas, 33 (20%) apresentaram contaminação por Salmonella estando, portanto, impróprias para o consumo conforme legislação brasileira.

Bactérias coliformes totais e coliformes de origem fecal em águas usadas na dessedentação de animais

Foram colhidas 105 amostras de água sendo 44 de mananciais e de 61 bebedouros, a partir das quais foram realizadas as determinações dos NMP (Número Mais Provável) de bactérias coliformes totais e fecais. de acordo com a Portaria GM/0013 de 15 de janeiro de 1976, da Secretaria Especial do Meio Ambiente do Ministério do Interior, os 44 mananciais revelaram-se dentro dos parâmetros estabelecidos. Embora não haja referência com relação a bebedouros, aplicando-se os valores estabelecidos para mananciais, das 61 amostras estudadas, somente 6 (9,8%) não poderiam ser usadas para a dessedentação de animais. Das 105 amostras analisadas, verificou-se que as condições sanitárias revelaram-se não satisfatórias em 6 (5,7%) amostras de bebedouros quanto a coliformes fecais, sendo 3 (2,8%) também com relação a coliformes totais.

Consequences of crown fractures with pulpal exposure: histopathological evaluation in dogs

When a crown fracture involving pulpal exposure is produced, the therapeutic treatment to be applied depends to a great extent on the general histopathological condition of the exposed pulp. Hence, the objective of this study was to evaluate histopathological and bacteriological changes occurring in dental tissue and periradicular tissue of crown-fractured teeth with pulpal exposure. Twenty-four anterior teeth (central and lateral incisors) from the maxillary teeth of four young, adult Mongrel dogs were used. At 48 and 72 h after performing the crown fractures, the animals were sacrificed and the results evaluated. Both observation periods revealed the existence of an area of superficial inflammation with the formation of hyperplastic tissue towards the external surface. Intense neutrophilic infiltrate was observed below it. Mean depth of inflammation was greater at 48 h (4633.33 mum) than at 72 h (3933.33 mum), perhaps coinciding with the bigger pulp chamber opening (x1332.14 mum at 48 h vs. x479.52 mum at 72 h). Upon approaching the cervical portion, the inflammation became less. Bacterial contamination was constant in all the cases evaluated, worsening the histopathological findings with exposure time. This study demonstrates that when a crown fracture with pulpal exposure is produced, the success in treating it depends partly on how quickly therapeutic treatment is administered.

Effect of saliva substitutes in combination with fluorides on remineralization of subsurface dentin lesions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Nanostructured films of perylene derivatives: High performance materials for taste sensor applications

Four perylene derivatives (PTCD) have been used as transducing materials in taste sensors fabricated with nanostructured Langmuir-Blodgett (LB) films deposited onto interdigitated gold electrodes. The Langmuir monolayers of PTCDs display considerable collapse pressures, with areas per molecule indicative of an edge-on or head-on arrangement for the molecules at the air/water interface. The sensing units for the electronic tongue were produced from 5-layer LB films of the four PTCDs, whose electrical response was characterized with impedance spectroscopy. The distinct responses of the PTCDs, attributed to differences in their molecular structures, allowed one to obtain a finger printing system that was able to distinguish tastes (salty, sweet, bitter and sour) at 1 μM concentrations, which, in some cases, are three orders of magnitude below the human threshold. Using Principal Component Analysis (PCA) data analysis, the electronic tongue also detected trace amounts of a pesticide and could distinguish among samples of ultrapure, distilled and tap water, and two brands of mineral water. © 2004 by American Scientific Publishers. All rights reserved.

Caracterização microbiológica do veneno do ferrão do Bagre (Cathorops agassizii and Genidens genidens)

This work aimed to study the bacterial contamination of the catfishes stings Genidens genidens (Valenciennes, 1839); and Cathorops agassizii (Agassiz, 1829) found in the estuary-bay complex of Santos and São Vicente (São Paulo State). Fish samples for bacteriological analyses were obtained and constituted of a group of 50 specimens, being 25 of Cathorops agassizii and 25 of Genidens genidens,. The bacteriological analyses showed that there was contamination of the stings by 13 different strains of Enterobacteriaceae with Klebsiella pneumoniae (26,80%) as the most frequent bacteria and lower percentual frequencies for Enterobacter sp and Escherichia coli (16,27%) and Serratia marcescens, Serratia sp. and Proteus mirabilis (1,16%). Gram positive bacteria, as well fungi species were not detected in the samples. In basis of the Gram negative species characterized, is possible to consider the bacterial strains are representative of the environmental public health conditions, as well as, accidents with these fish stings are able to develop significative acute secondary infections in humans.

Substrato e solução nutritiva desenvolvidos a partir de efluente de biodigestor para cultivo do meloeiro

Looking for the sustainability of a small farming enterprise, the present study focused the benefit of the biodigestor effluent resulting from the anaerobic fermentation of the bovine manure in a soilless melon plant experiment. The research was conducted in Jaboticabal, in the State of Sao Paulo, Brazil, at latitude of 21° 15' 22'' S and a longitude of 48° 18' 58'' W. The melon plant (Cucumis melo L. cv Bonus n° 2) was grown with substrate, seedling obtained in 10/2003. An experimental design was adapted in a randomized block with 16 treatments and 5 replications in a factorial 4 x 4 (4 substrates and 4 nutrient solutions). The 4 substrates were made up of different proportions in volume of the blend composition taking into consideration both the solid part of the biodigestor effluent and the washed raw sand. The 4 nutrient solutions were made up of the liquid part of the biodigestor effluent (biofertilizer) in substitution to the mineral water soluble fertilizers. The addition of the effluent in the sand led to a more rapid vegetative growth, a more precoceous crop with heavier fruits and a much better yield of melon crop. The mineral water soluble fertilizers used in the cultivation of plants in substrates can be partially replaced by the biofertilizer studied.