1,492 research outputs found
Cold-adapted yeasts from Patagonia Argentina
The Patagonian Andes possess a great variety of glaciers, large temperate ice masses, and glacially formed water bodies. Most of these environments are included in protected areas characterized by low anthropogenic impact and minimal atmospheric pollution. Studies on occurrence of psychrotolerant (cold-adapted) and psychrophilic yeasts in these natural environments have allowed the characterization of native cold-adapted yeast communities, the description of six novel species, as well as description of the capability of these yeasts to produce extracellular enzymes, and other metabolites (carotenoids and mycosporines). Cold-adapted yeasts from Patagonian glaciers were able to hydrolyze natural polymers (casein, lipids, starch, pectin and carboxymethylcellulose) at low temperatures and some were able to produce photo-protective compounds. These results suggest a significant ecological role of these organisms as organic matter decomposers and nutrient cyclers, also reveal that some of these yeasts could be used for further metabolic, ecological and biotechnological studies. The objective of this review is to summarize all the findings related to cold adapted yeasts from glacial environments of the South Hemisphere (outside Antarctica), also to highlight the importance of continental ice masses from the microbiological perspectiveFil: de Garcia, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; ArgentinaFil: Giraudo, Maria Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentin
DIVULGACIÓN CIENTÍFICA COMO EJE PARA EL DESARROLLO DE CONOCIMIENTO Y LA DEFENSA DE LA EDUCACIÓN
Divulgación científica como eje para el desarrollo de conocimiento y la defensa de la educación
Novel yeast taxa from the cold: description of Cryolevonia giraudoae sp. nov. and Camptobasidium gelus sp. nov.
Twenty-one psychrophilic yeast isolates related to the Camptobasidiaceae family in the Microbotryomycetes class were obtained from ice collected from cold environments worldwide. A new psychrophilic species from the recently described genus Cryole-vonia, Cryolevania giraudoae is proposed to accommodate 18 isolates from Patagonia (Argentina) and Antarctica (holotype CRUB 2086T). In addition, a new psychrophilic species in the genus Camptobasidium is described as Camptobasidium gelus sp. nov. (holotype CBS 8941T), based on three isolates from glacial ice in the Russel glacier (Greenland ice sheet) and Antarctica. The strict psychrophilic profile is the salient feature of both novel species.Fil: de Garcia, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Trochine, Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; ArgentinaFil: Uetake, Jun. National Institute of Polar Research; JapónFil: Bellora, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; ArgentinaFil: Libkind, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; Argentin
Divulgación científica como eje para el desarrollo de conocimiento y la defensa de la educación
La Facultad de Ciencias Agrarias (FaCA) de la Universidad Nacional del Comahue (UNCo), es una institución orientada y preparada para vincularse con al sector de la producción y la agroindustria, fortaleciendo líneas que nos permiten relacionarnos fuertemente con los productores, tanto grandes como los pequeños productores de la agricultura familiar, en un proceso donde se los pretende empoderar, para analizar y reflexionar sobre su realidad y plantear sus necesidades. Estas necesidades permiten el desarrollo de nuevos proyectos que pretenden dar respuesta a demandas o necesidades puntuales de cada uno de los sectores.Fil: de Garcia, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Brizzio, Juan Jose. Universidad Nacional del Comahue. Facultad de Ciencias Agrarias; Argentin
Yeasts Occurring in Surface and Mouth Cavity of Two Chelonian Species, Podocnemis expansa Schweigger and P. unifilis Troschel (Reptilia: Chelonia: Pelomedusidae), in the Javaés River Border of Araguaia National Park in Brazil
Thirty-eight specimens of free-ranging Podocnemis expansa (Amazon turtle) and 22 of P. unifilis (Tracajá) were screened for yeast isolation from surface (plastron, skin, and nails), eye, and mouth cavity. A hundred and eighteen yeast isolates belonging to 39 species were obtained. Debaryomyces hansenii, Candida galli, C. sake, and Rhodotorula mucilaginosa were the most frequent species isolated from these chelonians. Species diversity measured by Shannon's index was shown to be low and a degree of dominance could be detected as species known as potential pathogens were commonly isolated. The effective number of species in plastron of P. expansa was higher than in mouth samples, but not in P. unifilis probably due to dietary factors. P. expansa animals were captured on the beaches, and the superficial yeast populations may include terrestrial species. P. unifilis animals were captured in the water and the yeasts from superficial sites may represent species from river water
Environmental damage and dilemmas on theory of tort law
La temática de la responsabilidad extracontractual presenta muchas dificultades en su manejo, sobre todo cuando acercamos la responsabilidad civil al Derecho Ambiental percibimos que aquella tiene fragilizadas sus estructuras propias, surgiendo muchas incertidumbres en lo que toca a los fundamentos filosóficos y a las teorías clásicas de la responsabilidad. El artículo trata del daño ambiental, sus limitaciones y dilemas ante los fundamentos filosóficos de la responsabilidad extracontractual. Se dedica más atentamente a los problemas presentados por la responsabilidad objetiva e imputación en los supuestos de daño ambiental.The issue of Tort Law presents many difficulties, especially when we approach to Environmental responsability, arising many uncertainties regarding the philosophy foudations of tort law and insufficiency of the traditional concept on environmental damage. The article deals of Environmental damage and the limitations to the philosophy foudations of tort law, dedicates on problems presented by the objective responsibility and the assumptions of environmental damage.O tema da responsabilidade extracontratual apresenta muitas dificuldades em seu tratamento. Especialmente quando abordada a responsabilidade civil e o Direito Ambiental, percebemos que são enfraquecidas suas próprias estruturas, suscitando muitas incertezas quanto aos fundamentos filosóficos da responsabilidade extracontratual e teorias clássicas de responsabilidade. O artigo aborda o dano ambiental e suas limitações e dilemas ante a teoria geral e os fundamentos filosóficos da responsabilidade extracontratual. Dedica-se aos problemas apresentados pela responsabilidade objetiva e à imputação nos casos de danos ambientais
Evaluation of physicochemical and microbiological stability of liquid preparation from tizanidine hydrochloride tablets - a Hospital concern
Tizanidine hydrochloride is a centrally acting skeletal muscle relaxant, used in the management of spasticity. This drug is commercially available only as tablets, which highlights the need to develop oral liquid formulations. In the hospital environment, this aspect is circumvented by the preparation of suspensions, to allow administration to children and adults with impaired swallowing, but there are no data regarding their stability. The purpose of this study was to evaluate the physicochemical andmicrobiological stability of liquid dosage forms prepared in the hospital environment from tizanidine hydrochloride tablets, applying high performance liquid chromatography (HPLC) and microbiological analysis. A simple and stability-indicating HPLC method was developed and validated for specificity, linearity, limits of detection and quantification, precision, accuracy and robustness. The liquid formulations were placed in amber PET and glass bottles, which were stored under three different conditions: at room temperature, under refrigeration and at 40 ºC. The liquid formulations were analyzed and demonstrated chemical stability for 56 days, allowing their use for long periods. However, the determination of microbiological stability showed that these formulations are prone to microbial contamination, which has dramatically reduced its stability to 7 days, in both bottles and at all evaluated temperatures
Insulin-like growth factor I (IGF-I)-induced chronic gliosis and retinal stress lead to neurodegeneration in a mouse model of retinopathy
Insulin-like growth factor I (IGF-I) exerts multiple effects on different retinal cell types in both physiological and pathological conditions. Despite the growth factor's extensively described neuroprotective actions, transgenic mice with increased intraocular levels of IGF-I showed progressive impairment of electroretinographic amplitudes up to complete loss of response, with loss of photoreceptors and bipolar, ganglion, and amacrine neurons. Neurodegeneration was preceded by the overexpression of genes related to retinal stress, acute-phase response, and gliosis, suggesting that IGF-I altered normal retinal homeostasis. Indeed, gliosis and microgliosis were present from an early age in transgenic mice, before other alterations occurred, and were accompanied by signs of oxidative stress and impaired glutamate recycling. Older mice also showed overproduction of pro-inflammatory cytokines. Our results suggest that, when chronically increased, intraocular IGF-I is responsible for the induction of deleterious cellular processes that can lead to neurodegeneration, and they highlight the importance that this growth factor may have in the pathogenesis of conditions such as ischemic or diabetic retinopathy
Microbial contaminants in bottled craft beer of Andean Patagonia, Argentina
La actividad cervecera en la Patagonia andina argentina tiene un rol muy importante en la economía de la región; una de las problemáticas que enfrenta, en términos de calidad, son las contaminaciones microbianas. La presencia de bacterias y levaduras contaminantes en la cerveza produce cambios microbiológicos, físicos y químicos, que impactan en sus atributos sensoriales. No obstante, pocas cervecerías establecen criterios y políticas que garanticen la calidad microbiológica de sus productos. El propósito de este trabajo fue estudiar por primera vez la incidencia de contaminantes microbianos en cervezas artesanales embotelladas producidas en la Patagonia andina argentina, además de identificar los principales microorganismos involucrados y determinar posibles relaciones entre los eventos de contaminación y variables fisicoquímicas de la cerveza. Para ello se analizaron 75 cervezas provenientes de 37 cervecerías de 12 localidades andinas. El 69,3% de las muestras analizadas evidenció crecimiento de microorganismos en los medios de cultivo empleados para la detección de contaminantes cerveceros. La bacteria Levilactobacillus brevis y levaduras del género Saccharomyces fueron los principales contaminantes identificados. Se comprobó que las contaminaciones microbianas impactaron sobre el perfil sensorial de la cerveza y que el cambio de pH fue un indicador de contaminación por bacterias lácticas. De cada 10 fábricas estudiadas, 8 presentaron problemas de contaminación, lo que pone en evidencia la necesidad de disenar ˜ estrategias de prevención y control de contaminaciones en microcervecerías.The brewing activity in Andean Patagonia plays a very important role in the region´s economy, being microbial contamination one of the main problems in terms of quality. The presence of contaminant bacteria and wild yeasts in beer generate microbiological, physical and chemical changes that impact on its sensory attributes. However, few breweries establish criteria and policies to guarantee the quality of their products in a microbiological sense. The purpose of this work was to study for the first time the incidence of microbial contaminants in bottled craft beers from Andean Patagonia, identify the main microorganisms involved and establish relationships between contamination and the physicochemical variables of beer. We analyzed 75 beers from 37 breweries from 12 different Patagonian cities. Our results showed that 69.3% of the analyzed beer exhibited contaminant microorganism growth. Bacteria Levilactobacillus brevis and wild yeasts of Saccharomyces were the main microorganisms responsible for these contaminations. In addition, we found that microbial contamination had an impact on beer sensory profile and also that pH was correlated with the presence of lactic acid bacteria in beer, being an indicator of contamination for these bacteria. In conclusion, we observed that 8 out of 10 breweries studied showed contamination problems, highlighting the need to design prevention and control strategies in microbreweries.Fil: Latorre, Mailén Angelina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; ArgentinaFil: Bruzone, María Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales. Universidad Nacional del Comahue. Instituto Andino Patagónico de Tecnologías Biológicas y Geoambientales; ArgentinaFil: de Garcia, Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; ArgentinaFil: Libkind Frati, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas. Universidad Nacional del Comahue. Instituto de Investigación y Desarrollo en Ingeniería de Procesos, Biotecnología y Energías Alternativas; Argentin
UV spectrophotometric method for quantitative determination of agomelatine in coated tablets
UV spectrophotometry is an analytical technique used routinely for qualitative and quantitative assay due the low cost and reliability during analysis. In this work, it was validated a quantitative UV method for determination of agomelatine in coated tablets. The parameters specificity, linearity, precision, accuracy and robustness were evaluated according to official guidelines. Methanol was selected as solvent and the maximum wavelength for drug analysis was 230 nm. The purposed assay showed to be specific and the linearity was proved in a range of 0.5 - 2.5 μg/mL. The RSD values obtained during precision assay (inter-day RSD = 1.75%) indicated the method reproducibility, and the accuracy testing showed good results from recovery test. Robustness assay was complementary and showed that the purposed method is adequate for drug quantitation in commercial samples, being a reliable alternative to chromatographic assay
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