Characterization of Antibiotic-Resistance Antarctic Pseudomonas That Produce Bacteriocin-like Compounds.

In this study, bacterial isolates C1-4-7, D2-4-6, and M1-4-11 from Antarctic soil were phenotypically and genotypically characterized, and their antibacterial spectrum and that of cell-free culture supernatant were investigated. Finally, the effect of temperature and culture medium on the production of antimicrobial compounds was investigated. The three bacteria were identified as different strains of the genus Pseudomonas. The three bacteria were multi-drug resistant to antibiotics. They exhibited different patterns of growth inhibition of pathogenic bacteria. M1-4-11 was remarkable for inhibiting the entire set of pathogenic bacteria tested. All three bacteria demonstrated optimal production of antimicrobial compounds at 15 °C and 18 °C. Among the culture media studied, Nutrient broth would be the most suitable to promote the production of antimicrobial compounds. The thermostability exhibited by the antimicrobial molecules secreted, their size of less than 10 kDa, and their protein nature would indicate that these molecules are bacteriocin-like compounds.

Antarctic Soil Yeasts with Fermentative Capacity and Potential for the Wine Industry.

Low fermentation temperatures are usually employed to obtain high-quality wines. This is especially interesting for white wine production since it prevents the loss of volatile compounds and a browning appearance; however, available fermentative yeasts do not usually tolerate low temperatures. Therefore, an interesting place to find new yeasts with cryotolerance is the Antarctic continent. From soil samples collected in Antarctica, 125 yeasts were isolated, of which 25 exhibited fermentative activity at 10 °C. After a fingerprinting assay, we classified the candidates into nine isotypes and sequenced internal transcribed spacer regions for their identification. These yeasts were identified as part of the Mrakia genus. Sugar and alcohol tolerance tests showed that some of these Antarctic soil yeasts were able to grow up to 9% alcohol, and 25% sugar was reached; however, they exhibited longer latency periods compared to the control Saccharomyces cerevisiae. The optimal growing temperature for the isolated Antarctic yeasts was between 10 °C and 15 °C. A comprehensive analysis of the results obtained showed that the isolates 10M3-1, 4M3-6, and 4B1-35 could be good candidates for fermentation purposes due to their alcohol, sugar tolerance, and growth features. Our results prove that it is possible to isolate fermentative yeasts from Antarctic soil with promising characteristics for their potential use in the wine production industry.

Gut-Brain Axis Deregulation and Its Possible Contribution to Neurodegenerative Disorders.

The gut-brain axis is an essential communication pathway between the central nervous system (CNS) and the gastrointestinal tract. The human microbiota is composed of a diverse and abundant microbial community that compasses more than 100 trillion microorganisms that participate in relevant physiological functions such as host nutrient metabolism, structural integrity, maintenance of the gut mucosal barrier, and immunomodulation. Recent evidence in animal models has been instrumental in demonstrating the possible role of the microbiota in neurodevelopment, neuroinflammation, and behavior. Furthermore, clinical studies suggested that adverse changes in the microbiota can be considered a susceptibility factor for neurological disorders (NDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and amyotrophic lateral sclerosis (ALS). In this review, we will discuss evidence describing the role of gut microbes in health and disease as a relevant risk factor in the pathogenesis of neurodegenerative disorders, including AD, PD, HD, and ALS.

Identification of antarctic soil bacteria exhibiting antiproliferative activity against a colon cancer cell line / Identificación de bacterias de suelo antártico que presentan actividad antiproliferativa sobre una línea celular de cáncer de colon

SUMMARY: Cancer is the second leading cause of death in the world and colorectal cancer is the only cancer that has shown a sustained increase in mortality in the last decade. In the search for new chemotherapeutic agents against cancer, extremophilic microorganisms have shown to be a potential source to obtain molecules of natural origin and with selective cytotoxic action towards cancer cells. In this work we analyzed the ability of a collection of Antarctic soil bacteria, isolated on Collins Glacier from the rhizosphere of Deschampsia antarctica Desv plant, to secrete molecules capable of inhibiting cell proliferation of a colorectal cancer tumor line. Our results demonstrated that culture supernatants from the Antarctic bacteria K2I17 and MI12 decreased the viability of LoVo cells, a colorectal adenocarcinoma cell line. Phenotypic and genotypic characterization of the Antarctic bacteria showed that they were taxonomically related and nucleotide identity analysis based on the 16S rRNA gene sequence identified the bacterium K2I17 as a species belonging to the genus Bacillus.

El cáncer es la segunda causa de muerte en el mundo y el cáncer colorrectal es el único que presenta un aumento sostenido de la mortalidad en la última década. En la búsqueda de nuevos agentes quimioterapeúticos contra el cáncer, se ha propuesto a los microorganismos extremófilos como una fuente potencial para obtener moléculas de origen natural y con acción citotóxica selectiva hacia las células cancerígenas. En este trabajo analizamos la capacidad de una colección de bacterias de suelo antártico, aisladas en el glaciar Collins desde rizosfera de la planta de Deschampsia antarctica Desv, de secretar moléculas capaces de inhibir la proliferación celular de una línea tumoral de cáncer colorrectal. Nuestros resultados demostraron que los sobrenadantes de cultivo de las bacterias antárticas K2I17 y MI12 disminuyeron la viabilidad de la línea celular de adenocarcinoma colorrectal LoVo, en un ensayo de reducción metabólica de MTT. La caracterización fenotípica y genotípica de las bacterias antárticas, demostró que estaban relacionadas taxonómicamente y el análisis de la identidad nucleotídica en base a la secuencia del gen ARNr 16S identificó a la bacteria K2I17 como una especie perteneciente al género Bacillus.

Carotenoid Cocktail Produced by An Antarctic Soil Flavobacterium with Biotechnological Potential.

Carotenoids are highly important in pigmentation, and its content in farmed crustaceans and fish correlates to their market value. These pigments also have a nutritional role in aquaculture where they are routinely added as a marine animal food supplement to ensure fish development and health. However, there is little information about carotenoids obtained from Antarctic bacteria and its use for pigmentation improvement and flesh quality in aquaculture. This study identified carotenoids produced by Antarctic soil bacteria. The pigmented strain (CN7) was isolated on modified Luria-Bertani (LB) media and incubated at 4 °C. This Gram-negative bacillus was identified by 16S rRNA analysis as Flavobacterium segetis. Pigment extract characterization was performed through high-performance liquid chromatography (HPLC) and identification with liquid chromatography-mass spectrometry (LC-MS). HPLC analyses revealed that this bacterium produces several pigments in the carotenoid absorption range (six peaks). LC-MS confirms the presence of one main peak corresponding to lutein or zeaxanthin (an isomer of lutein) and several other carotenoid pigments and intermediaries in a lower quantity. Therefore, we propose CN7 strain as an alternative model to produce beneficial carotenoid pigments with potential nutritional applications in aquaculture.

La controversia científico-técnica sobre las benzodiacepinas en profesionales de la salud pública de Uruguay / A controvérsia científico-técnica sobre as benzodiazepinas entre profissionais de saúde pública do Uruguai / The scientific-technical controversy over benzodiazepines among public health professionals in Uruguay

Resumen La controversia científico-técnica internacional sobre las benzodiacepinas, intensa durante los años ochenta y noventa, cuestionó su lugar en la práctica clínica, por su potencialidad adictiva, y por el abuso que médicos y pacientes parecerían realizar. Este artículo presenta resultados de una investigación que tuvo como objetivo analizar el papel de dicha controversia en las prácticas médica, psiquiátrica y psicológica en los servicios de salud pública uruguayos. Se utilizó metodología cualitativa y se combinó relevamiento de artículos académicos nacionales (1960-2012), entrevistas en profundidad a 45 profesionales y dos grupos de discusión. Se efectuó análisis de contenido desde cuatro ejes: ansiedad en la clínica, prescripción, relación tratamientos farmacológicos con no farmacológicos y valoración de benzodiacepinas. Se obtuvo un panorama diacrónico de la controversia académica y se identificó una valoración condicional de estos medicamentos realizada por los profesionales que supone: reconocimiento de atributos positivos y negativos de las benzodiacepinas, uso mesurado, médicos y pacientes vigilantes de sus propios comportamientos. Se concluye que la controversia se plantea en términos individuales, lo que obstaculiza una discusión global de las dimensiones políticas y colectivas implicadas.

Resumo A controvérsia científico-técnica internacional sobre as benzodiazepinas, intensa durante os anos 1980 e 1990, questionou seu lugar na prática clínica devido a sua potencialidade aditiva e pelo abuso que médicos e pacientes pareciam realizar. Este artigo apresenta resultados de uma pesquisa que teve como objetivo analisar o papel dessa controvérsia nas práticas médica, psiquiátrica e psicológica nos serviços de saúde pública do Uruguai. Utilizou-se metodologia qualitativa e combinou-se um levantamento de artigos acadêmicos nacionais (1960-2012), entrevistas em profundidade com 45 profissionais e dois grupos de discussão. Realizou-se análise de conteúdo a partir de quatro eixos: ansiedade na clínica, prescripção, relação entre tratamentos farmacológicos e não farmacológicos e avaliação das benzodiacepinas. Obteve-se um panorama diacrônico da controvérsia acadêmica e identificou-se uma avaliação condicional desses medicamentos realizada pelos profissionais, que supõe: reconhecimento de atributos positivos e negativos das benzodiazepinas, uso controlado, médicos e pacientes vigilantes de seus próprios comportamentos. Conclui-se que a controvérsia é levantada em termos individuais, o que obstaculiza uma discussão global das dimensões políticas e coletivas implicadas.

Abstract The international technoscientific controversy on benzodiazepines, especially intense during the 1980s and 1990s, questioned the place of benzodiazepines in clinical practice because of its addictive potentiality and the abuse of physicians and patients. This article presents some results from a research that aimed to analyze the role of benzodiazepine controversy in medical, psychiatric and psychological practices in Uruguayan public health services. This research methodology was qualitative, combining a review of national academic articles (1960-2012), in-depth interviews with 45 professionals and two discussion groups. Content analysis was carried out using four axes: anxiety in clinic practice, prescription, relationship between pharmacologic and non-pharmacologic treatment, and benzodiazepines valoration. We obtained a diachronic pictures of the academic controversy and we identified a conditional assessment of these medicines made by the professionals. This assessment implies: the recognition of positive and negative attributes of benzodiazepines, a controlled use of benzodazepines, and professionals and patients that must watch their own behaviors. We conclude that the controversy is presented mainly in individual terms, and this prevents a global discussion on the political and collective dimensions involved.

Estereotipia social en los profesionales de la salud pública de Uruguay acerca del uso de benzodiazepinas / Social stereotyping in public health professionals of Uruguay on benzodiazepine use

Se presentan los resultados de una investigación cualitativa que tuvo como objetivo analizar el papel de la controversia sobre la utilidad clínica de las benzodiazepinas en las prácticas de la Medicina General, la Psiquiatría y la Psicología en los servicios de salud pública del Uruguay. La metodología empleada combinó la realización de entrevistas en profundidad y los grupos de discusión y una revisión documental. Se observa un desplazamiento de la valoración (positiva o negativa) de la sustancia, a la valoración de su utilización por parte de los médicos y los usuarios, moralizando sus conductas. Se identificaron en los profesionales distintos procesos de estereotipación y moralización de las conductas de los pacientes, que complejizan la práctica clínica y el acto de prescripción, obstaculizando la posibilidad de visualizar alternativas al uso de las benzodiazepinas.(AU)

This article presents the results of a qualitative study that aimed at analyzing the role of controversy on the clinical utility of benzodiazepines in clinical practices of General Medicine, Psychiatry and Psychology of public health services in Uruguay. Themethodology associated the conduction of in depth interviews with discussion groups and a documental review. It is seen a shift from the substance assessment (positive or negative) to the assessment of the benzodiazepine use by physicians and users, thus moralizing their behavior. Stereotyping and moralizing processes of the patients' behavior were identifid among diffrent health professionals, which make the clinical practice and the act of prescribing more complex, hindering the chance of visualizing alternatives to the use of benzodiazepines.(AU)

Estereotipia social en los profesionales de la salud pública de Uruguay acerca del uso de benzodiazepinas / Social stereotyping in public health professionals of Uruguay on benzodiazepine use

Se presentan los resultados de una investigación cualitativa que tuvo como objetivo analizar el papel de la controversia sobre la utilidad clínica de las benzodiazepinas en las prácticas de la Medicina General, la Psiquiatría y la Psicología en los servicios de salud pública del Uruguay. La metodología empleada combinó la realización de entrevistas en profundidad y los grupos de discusión y una revisión documental. Se observa un desplazamiento de la valoración (positiva o negativa) de la sustancia, a la valoración de su utilización por parte de los médicos y los usuarios, moralizando sus conductas. Se identificaron en los profesionales distintos procesos de estereotipación y moralización de las conductas de los pacientes, que complejizan la práctica clínica y el acto de prescripción, obstaculizando la posibilidad de visualizar alternativas al uso de las benzodiazepinas.

This article presents the results of a qualitative study that aimed at analyzing the role of controversy on the clinical utility of benzodiazepines in clinical practices of General Medicine, Psychiatry and Psychology of public health services in Uruguay. Themethodology associated the conduction of in depth interviews with discussion groups and a documental review. It is seen a shift from the substance assessment (positive or negative) to the assessment of the benzodiazepine use by physicians and users, thus moralizing their behavior. Stereotyping and moralizing processes of the patients' behavior were identifid among diffrent health professionals, which make the clinical practice and the act of prescribing more complex, hindering the chance of visualizing alternatives to the use of benzodiazepines.