547 research outputs found

    Biosurfactants produced by Pseudomonas syringae pv tabaci: A versatile mixture with interesting emulsifying properties

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    In recent years, worldwide awareness about environmental concerns has led to an extensive searching for products of natural origin. Biosurfactants (BS), are an attractive alternative to the chemical counterparts. In these sense, this works evaluate for the first time the emulsifying and surface activity of biosurfactants produced by P. syringae pv. tabaci. Chemical characterization revealed that the produced BS extract mostly consisted in a mixture of syringopeptins and arthrofactins. Besides, this sample was able to reduce water surface tension up to 36.89 mN/m. This activity was improved by modifying conditions of pH, temperature and salinity. For instance, the surface tension was reduced up to 29 mN/m when using NaCl 5 % w/w. The BS also exhibited a high emulsifying activity, this being comparable or even superior to that of commercial bioemulsifiers such xanthan, tara and guar gums. A notorious emulsification index, close to 90 %, was exhibited by BS in coconut oil/water mixtures. Moreover, emulsifying activity resulted to be little affected by different operational conditions, thus retaining about 80 % of its emulsificant index in presence of 20 % w/w of NaCl at 80 °C. These findings are indicative of the BS promising properties and its potential as additive in a variety of industrial applications.Fil: Haidar, Carla Nahir. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; ArgentinaFil: Pereira, Matheus M.. Universidade Tiradentes; BrasilFil: Lima, Álvaro S.. Universidade Tiradentes; BrasilFil: Nerli, Bibiana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; ArgentinaFil: Pellegrini Malpiedi, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Procesos Biotecnológicos y Químicos Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Procesos Biotecnológicos y Químicos Rosario; Argentin

    Potential changes in the connectivity of marine protected areas driven by extreme ocean warming

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    Projected future climate scenarios anticipate a warmer tropical ocean and changes in surface currents that will likely influence the survival of marine organisms and the connectivity of marine protected areas (MPAs) networks. We simulated the regional effects of climate change on the demographic connectivity of parrotfishes in nine MPAs in the South Atlantic through downscaling of the HadGEM2-ES Earth System Model running the RCP 8.5 greenhouse gas trajectory. Results indicate a tropicalization scenario over the tropical southwest Atlantic following an increase of sea surface temperature (SST) between 1.8 and 4.5 °C and changes in mean surface currents between − 0.6 to 0.5 m s−1 relative to present conditions. High mortality rates will reduce demographic connectivity and increase the isolation of oceanic islands. The simulation of organismal response to ocean warming shows that acclimation can significantly improve (p < 0.001) particle survival, promoting connectivity and tropicalization of MPAs, with potential impacts on their functional integrity and long-term resilience.publishedVersio

    Type 2 diabetes mellitus and the prevalence of apical periodontitis and endodontic treatment in an adult Brazilian population

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    Introduction This cross-sectional study evaluated the prevalence of apical periodontitis (AP) and endodontic treatment in type 2 diabetic individuals as compared with nondiabetics from an adult Brazilian population. Methods Full-mouth radiographs from 30 type 2 diabetic and 60 age- and sex-matched nondiabetic individuals were examined, and the presence of AP lesions in untreated and root canal-treated teeth was recorded. The number of teeth and the prevalence of root canal treatment were also evaluated. Results AP was significantly more present in teeth from diabetic individuals (98/652, 15%) than in nondiabetic controls (162/1,368, 12%) (P = .05). A separate analysis of untreated and treated teeth revealed that significance was mostly because of the prevalence of AP in untreated teeth, which was 10% in diabetics and 7% in nondiabetics (P = .03). No significant difference between diabetics and nondiabetics was observed for the other parameters under study, including the prevalence of AP in root canal–treated teeth, the number of teeth in the oral cavity, the number of treated teeth per individual, the number of individuals with at least 1 AP lesion or 1 root canal treatment, and the number of teeth with AP per individual (P > .05). Conclusions AP was significantly more prevalent in untreated teeth from type 2 diabetics. This suggests that diabetes may serve as a disease modifier of AP in the sense that individuals with diabetes can be more prone to develop primary disease. However, findings do not confirm that diabetes may influence the response to root canal treatment because treated teeth had no increased prevalence of AP when compared with controls

    Antifungal activity of schinol and a new biphenyl compound isolated from Schinus terebinthifolius against the pathogenic fungus Paracoccidioides brasiliensis

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    <p>Abstract</p> <p>Background</p> <p>The aim of this study was to isolate and identify the antifungal compounds from the extracts of <it>Schinus terebinthifolius </it>(Anacardiaceae) against clinical isolates of the pathogenic fungus <it>Paracoccidioides brasiliensis</it>.</p> <p>Methods</p> <p>The hexane and dichlomethane fractions from leaves and stems of <it>S. terebinthifolius </it>were fractionated using several chromatography techniques to afford four compounds.</p> <p>Results</p> <p>The compounds isolated from <it>S. terebinthifolius </it>were identified as schinol (<b>1</b>), a new biphenyl compound, namely, 4'-ethyl-4-methyl-2,2',6,6'-tetrahydroxy[1,1'-biphenyl]-4,4'-dicarboxylate (<b>2</b>), quercetin (<b>3</b>), and kaempferol (<b>4</b>). Compounds <b>1 </b>and <b>2 </b>were active against different strains of <it>P. brasiliensis</it>, showing a minimal inhibitory concentration value against the isolate Pb B339 of 15.6 ÎŒg/ml. The isolate Pb 1578 was more sensitive to compound <b>1 </b>with a MIC value of 7.5 ÎŒg/ml. Schinol presented synergistic effect only when combined with itraconazole. The compounds isolated from S. <it>terebinthifolius </it>were not able to inhibit cell wall synthesis or assembly using the sorbitol assay.</p> <p>Conclusion</p> <p>This work reveals for the first time the occurrence of compound <b>2 </b>and discloses activity of compounds <b>1 </b>and <b>2 </b>against several clinical isolates of <it>P. brasiliensi</it>s. These results justify further studies to clarify the mechanisms of action of these compounds.</p

    Tissue distribution of DNA-Hsp65/TDM-loaded PLGA microspheres and uptake by phagocytic cells

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    This study aimed to demonstrate that microspheres, used as delivery vehicle of DNA-Hsp65/TDM [plasmid DNA encoding heat shock protein 65 (Hsp65) coencapsulated with trehalose dimycolate (TDM) into PLGA microspheres], are widely spread among several organs after intramuscular administration in BALB/c mice. In general, we showed that these particles were phagocytosed by antigen presenting cells, such as macrophages and dendritic cells. Besides, it was demonstrated herein that draining lymph node cells presented a significant increase in the number of cells expressing costimulatory molecules (CD80 and CD86) and MHC class II, and also that the administration of the DNA-Hsp65/TDM and vector/TDM formulations resulted in the up-regulation of CD80, CD86 and MHC class II expression when compared to control formulations (vector/TDM and empty). Regarding the intracellular trafficking we observed that following phagocytosis, the microspheres were not found in the late endosomes and/or lysosomes, until 15 days after internalization, and we suggest that these constructions were hydrolysed in early compartments. Overall, these data expand our knowledge on PLGA [poly (lactic-co- glycolic acid)] microspheres as gene carriers in vaccination strategies, as well as open perspectives for their potential use in clinical practice

    Determinants of bone mineral density in post-menopause

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    PĂłs-menopausa Ă© perĂ­odo de maior perda Ăłssea e faz-se necessĂĄrio instituir medidas preventivas que amenizem sua progressĂŁo. Objetivo: correlacionar o escore da densidade mineral Ăłssea (DMO) e seus fatores de risco, buscando determinar aqueles que mais a influenciam. MĂ©todo: estudo transversal, descritivo de 62 mulheres na pĂłs-menopausa, saudĂĄveis, idade mĂ©dia de 56,82 ± 4,02 anos, avaliadas quanto aos fatores de risco para osteoporose e nĂ­vel de atividade fĂ­sica. Absorção de dupla energia de raios-X (DXA) avaliou coluna lombar e fĂȘmur proximal. Os grupos, DMO normal e diminuĂ­da, foram analisados pelos testes T de Student, qui-quadrado e correlaçÔes. Resultados: Mulheres com menor Ă­ndice de massa corporal (IMC), maior idade e maior tempo de menopausa apresentaram menor DMO em fĂȘmur. Raça negra e ausĂȘncia de histĂłria familiar correlacionaram-se com maior DMO. ConclusĂŁo: IMC, idade, peso, histĂłria familiar de osteoporose, raça e tempo de menopausa foram os principais fatores determinantes da DMO em mulheres na pĂłs-menopausaPost-menopause is the period of greatest bone loss and it is necessary to introduce preventative measures to mitigate its progression. Aim: compare the score of bone mineral density (BMD) and their risk factors and to determine those most influencing. Method: Cross-sectional, descriptive study of 62 postmenopausal women, healthy, average age 56.82 ± 4.02 years, evaluated for risk factors for osteoporosis and physical activity level. Absorption dual energy X-ray absorptiometry (DXA) evaluated lumbar spine and proximal femur. Groups, normal and reduced BMD were analyzed by Student’s t test, chisquare and correlations. Results: Women with lower body mass index (BMI), older age and longer duration of menopause had lower BMD at the femur. Black race and absence of family history correlated with higher BMD. Conclusion: BMI, age, weight, family history of osteoporosis, race, and time since menopause were the main determinants of BMD in postmenopausal wome

    Prevalence and etiology of anemia in the elderly: a full review

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    Purpuses: to describe the prevalence and etiology of anemia in the elderly in the original studies published. Methods: systematic review of articles published between 2008 and 2013, the electronic databases PubMed and Science Direct. Using descriptors predetermined english, covering articles that used: “anemia”, “elderly”, “etiology”, used in combination. Results: was founded 77 articles. After filtering process were selected 18 studies that presented results of prevalence and etiology of anemia in the elderly. Conclusion: there was a wide range in the prevalence of anemia (5.5% to 62.6%), as well as the etiology. Hospitalized and institutionalized elderly showed a high prevalence of anemia with increased risk for mortality. Non-institutionalized elderly constituted the majority of the target population and the main cause of anemia was chronic and unexplained. The etiology of anemia found in these surveys included the three main causes of anemia in the elderly, which is by nutritional deficiencies, chronic and unexplained anemia, confirming this multifactorial disease.Objetivos: Descrever a prevalĂȘncia e a etiologia da anemia em idosos nos estudos originais publicados. MĂ©todos: RevisĂŁo integrativa de artigos publicados entre 2008 e 2013, nas bases de dados eletrĂŽnicos PubMed e Science Direct. Utilização de descritores prĂ©-determinados em inglĂȘs, abrangendo artigos que utilizassem: “anemia”, “elderly”, “etiology”, usados em combinação. Resultados: Foram encontrados 77 artigos. ApĂłs processo de filtragem selecionou-se 18 estudos que apresentavam resultados da prevalĂȘncia e etiologia da anemia em idosos. ConclusĂŁo: Observou-se grande amplitude nas prevalĂȘncias de anemias (5,5% a 62,6%), assim como a etiologia. Idosos hospitalizados e institucionalizados apresentaram elevadas prevalĂȘncias de anemia com aumento para risco de mortalidade. Idosos nĂŁo institucionalizados constituĂ­ram a maior parte da população alvo e nesses, a principal etiologia da anemia foi doença crĂŽnica e inexplicada. A etiologia da anemia encontrada nestas pesquisas contemplou as trĂȘs principais causas de anemia nos idosos, quais seja por deficiĂȘncias nutricionais, doenças crĂŽnicas e anemia inexplicada, confirmando a multifatorialidade desta doença
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