998 resultados para Konrath, Sara
Resumo:
Obesity is considered a major health problem. However, mechanisms involved and its comorbidities are not elucidated. Recent theories concerning the causes of obesity have focused on a limit to the functional capacity of adipose tissue, comparing it with other vital organs. This assumption has been the central point of interest in our laboratory. We proposed that the failure of adipose tissue is initiated by the difficulty of this tissue to increase its cellularity due to excess in fat contribution, owing to genetic or environmental factors. Nevertheless, why the adipose tissue reduces its capacity to make new adipocytes via mesenchymal cells of the stroma has not yet been elucidated. Thus, we suggest that this tissue ceases fulfilling its main function, the storage of excess fat, thereby affecting some of the key factors involved in lipogenesis, some of which are reviewed in this paper (PPARγ, ROR1, FASN, SCD1, Rab18, BrCa1, ZAG, and FABP4). On the other hand, mechanisms involved in adipose tissue expandability are also impaired, predominating hypertrophy via an increase in apoptosis and a decrease in adipogenesis and angiogenesis. However, adipose tissue failure is only part of this great orchestra, only a chapter of this nightmare.
Resumo:
The serum and urine proteins responsible for enhanced pigment production in Streptococcus agalactiae in culture media were purified by chromatography and were identified as amylases by comparison of their amino acid composition with that calculated for proteins with known sequences. Similar pigment-enhancing activity was displayed by other amylases of nonanimal origin and by maltooligosaccharides.
Resumo:
Gut microbiota has recently been proposed as a crucial environmental factor in the development of metabolic diseases such as obesity and type 2 diabetes, mainly due to its contribution in the modulation of several processes including host energy metabolism, gut epithelial permeability, gut peptide hormone secretion, and host inflammatory state. Since the symbiotic interaction between the gut microbiota and the host is essentially reflected in specific metabolic signatures, much expectation is placed on the application of metabolomic approaches to unveil the key mechanisms linking the gut microbiota composition and activity with disease development. The present review aims to summarize the gut microbial-host co-metabolites identified so far by targeted and untargeted metabolomic studies in humans, in association with impaired glucose homeostasis and/or obesity. An alteration of the co-metabolism of bile acids, branched fatty acids, choline, vitamins (i.e., niacin), purines, and phenolic compounds has been associated so far with the obese or diabese phenotype, in respect to healthy controls. Furthermore, anti-diabetic treatments such as metformin and sulfonylurea have been observed to modulate the gut microbiota or at least their metabolic profiles, thereby potentially affecting insulin resistance through indirect mechanisms still unknown. Despite the scarcity of the metabolomic studies currently available on the microbial-host crosstalk, the data-driven results largely confirmed findings independently obtained from in vitro and animal model studies, putting forward the mechanisms underlying the implication of a dysfunctional gut microbiota in the development of metabolic disorders.
Resumo:
Com base na nova economia institucional, o foco da pesquisa aqui relatada foi identificar os custos de transação existentes nos projetos de Mecanismo de Desenvolvimento Limpo (MDL) e investigar se eles são barreiras para o desenvolvimento do projeto e se podem afetar a eficiência de projetos já implantados. Mais especificamente, foram analisadas as variáveis que afetam as diferenças entre as reduções de emissões estimadas nos projetos de MDL e as reduções realmente verificadas (sucesso de redução - SR), depois do projeto implantado e monitorado, verificando se os projetos agrícolas são mais ou menos eficientes. Em relação ao SR, a maior parte dos projetos não apresenta desempenho satisfatório. No entanto, em volume de reduções, a maior parte dos projetos cumpre mais do que 91% de SR. Os setores mundiais mais eficientes no Brasil são N2O e troca de energia fóssil; os menos eficientes, os setores de agricultura e resíduos sólidos. Finalmente, concluiu-se na pesquisa que os custos de transação afetam o sucesso da redução de MDL, e os mais importantes são os custos ex ante, resultantes de problemas de falhas de informação e problemas de mensuração.
Resumo:
Local flaps are the standard procedure to reconstruct facial defects. As it occurs in any surgical procedure, the incision should be planned so that scars are located in the minimum skin tension lines. We report two cases of O to Z flaps in the supra and infraciliary regions. One of them is a hatchet flap.
Resumo:
The Leishmania genus is formed by parasitic protozoa which are transmitted by the bite of infected female sand flies. Cases of sexual, vertical or transfusional transmission or via infected needles have also been described. In humans, 4 forms of this disease have been described: localised cutaneous (LC), diffuse cutaneous, mucocutaneous and visceral (1). LC counts for 50–75% of all cases (2), it is the mildest form of the disease and can be caused by any species of Leishmania. In Spain, the most frequent form is the oriental sore caused by L. infantum (2). Most cases resolve spontaneously within one year. In United States and Europe, the incidence is increasing due to tourism and co-infection with HIV. The morphological spectrum of LC is very wide; multiple forms of clinical presentation have been described, although the most characteristic one is the nodular ulcerative lesion, characterised by painless crater-like ulcers with a necrotic base and covered by an adhesive crust. The main complication of LC is its progression in some strains towards the other 3 forms of the disease (3). In patients with AIDS and other diseases associated with immunosuppression the risk of dissemination is much higher than in the immunocompetent. We present a case of LC with clinical and histopathological features similar to a pyogenic granuloma.
Resumo:
In this paper a one-phase supercooled Stefan problem, with a nonlinear relation between the phase change temperature and front velocity, is analysed. The model with the standard linear approximation, valid for small supercooling, is first examined asymptotically. The nonlinear case is more difficult to analyse and only two simple asymptotic results are found. Then, we apply an accurate heat balance integral method to make further progress. Finally, we compare the results found against numerical solutions. The results show that for large supercooling the linear model may be highly inaccurate and even qualitatively incorrect. Similarly as the Stefan number β → 1&sup&+&/sup& the classic Neumann solution which exists down to β =1 is far from the linear and nonlinear supercooled solutions and can significantly overpredict the solidification rate.
Resumo:
El proyecto realizado, se basa en la producción de acrilonitrilo mediante el proceso Sohio. El proceso consiste en la amonoxidación catalítica del propileno, mediante un catalizador de óxidos de metales tales como vanadio y molibdeno. Junto al acrilonitrilo se obtienen como subproductos sulfato de amonio, cianuro de hidrógeno y acetonitrilo “bruto”. Éste último es utilizado como materia prima por otras industrias. Para lograr el objetivo del proyecto, se requiere de un reactor catalítico de tipo lecho fluidizado de grandes dimensiones y por ello, se opta por duplicarlo. También se requiere un cristalizador, para la obtención de la sal de amonio, y además un conjunto de 9 columnas de separación, de las cuales dos son de absorción, cinco de rectificación convencionales y dos de rectificación especiales. Estas dos últimas columnas, son necesarias para la ruptura de los azeótropos resultantes de la interacción acrilonitriloagua y acrilonitrilo-agua, respectivamente (se tiene en una de las dos columnas, una mezcla ternaria acrilonitrilo-acetonitrilo-agua). Debido a la naturaleza de los compuestos manipulados, es estrictamente necesario disponer de unas medias de seguridad especiales en toda la planta, así como en el parque de tanques. Además, hace falta destacar que el proceso, requiere un sistema de control de notable envergadura, (alrededor de 300 señales analógicas y digitales), debido a la complejidad del tren de purificación. En el proceso se intenta optimizar, tanto el consumo de recursos (reutilización del agua generada en el reactor para su uso como absorbente en las unidades de Quench y absorción), como el consumo energético (aprovechamiento de flujos calientes para precalentar otros fríos, generación de vapor en el reactor y a lo largo del proceso con corrientes que requieren de enfriamiento de caudales elevados a altas temperaturas, generación de electricidad con una turbina de cogeneración…). A pesar de esto, no se consiguen beneficios económicos, considerándolo así económicamente inviable. Este ha sido el resultado del estudio del flujo de caja de cada año que siempre ha resultado negativo debido a los elevados costes de producción. Finalmente, se proponen posibles mejoras para hacer viable el proceso. Algunas de estas son: cambiar la materia prima por otra de menor coste (propano en vez de propileno), cambiar el catalizador por uno de conversión mayor, minimizar los costes de tratamiento de residuos reduciendo así los gastos de nueva materia prima, u optimizar el proceso incrementado el precio del inmovilizado para disminuir el coste de producción.
Interferência do intervalo de administração da droga sobre a nefrotoxicidade da gentamicina em ratos
Resumo:
A insuficiência renal aguda (IRA) que apresenta índice de mortalidade em torno de 50%, pode ser definida como um abrupto declínio da filtração glomerular, resultante de isquemia ou toxicidade. A nefrotoxicidade por drogas é uma das etiologias mais freqüentes (27%) e sugere-se que o intervalo de administração da droga pode interferir neste efeito colateral, entretanto o melhor regime de administração ainda não está bem estabelecido. Este conhecimento proporcionaria uma atuação mais direcionada de enfermagem na prevenção desta IRA hospitalar. Os resultados obtidos nesta pesquisa, indicam que a infusão única de gentamicina determina menor nefrotoxicidade, provavelmente devido à redução da sua concentração plasmática nas 24hs, diminuindo o acúmulo intracelular deste fármaco, um dos principais mecanismos celulares deste tipo de lesão. Este regime de tratamento mostra portanto vantagens quanto ao custo, efeito nefrotóxico e segurança quanto à eficácia terapêutica.
Resumo:
Durant el segle XIX i les primeres dècades del XX, Àsia Central va patir de primera mà la rivalitat entre les dues grans potències europees del moment: Anglaterra i Rússia. Aquest enfrontament va ser batejat pels seus propis participants amb el nom d'El Gran Joc. A diferència d'altres lluites històriques prèvies, el Gran Joc no es va resumir en una guerra, sinó en un cúmul d'elles, que es van succeir al llarg del temps en diferents territoris del centre del continent asiàtic i a les que van acompanyar accions diplomàtiques igualment nombroses. Tot i l'extensió del conflicte, Afganistan es va erigir com el punt clau més rellevant al voltant del qual l'Imperi rus i el britànic van desenvolupar les seves intrigues. Els dos poders europeus, amb els seus respectius objectius en ment, no van dubtar a dur a terme un dels majors desplegaments estratègics mai vist a la zona, valent-se, a més dels seus efectius, dels habitants asiàtics com peons al tauler del seu joc i marcant profundament el futur de les nacions centreasiàtiques, així com establint un precedent en la manera de fer la guerra on la victòria d'una facció sobre una altra mai estaria clara.
Resumo:
Acquiring lexical information is a complex problem, typically approached by relying on a number of contexts to contribute information for classification. One of the first issues to address in this domain is the determination of such contexts. The work presented here proposes the use of automatically obtained FORMAL role descriptors as features used to draw nouns from the same lexical semantic class together in an unsupervised clustering task. We have dealt with three lexical semantic classes (HUMAN, LOCATION and EVENT) in English. The results obtained show that it is possible to discriminate between elements from different lexical semantic classes using only FORMAL role information, hence validating our initial hypothesis. Also, iterating our method accurately accounts for fine-grained distinctions within lexical classes, namely distinctions involving ambiguous expressions. Moreover, a filtering and bootstrapping strategy employed in extracting FORMAL role descriptors proved to minimize effects of sparse data and noise in our task.
Resumo:
En s'appuyant sur les acquis démontrés de l'entretien motivationnel individuel chez les patients psychotiques consommateurs de cannabis, une équipe suisse a complété leur prise en charge individuelle par des groupes motivationnels. Le format de ces groupes mobilise davantage ces patients et favorise notamment une mise en scène de la balance décisionnelle.
Resumo:
L’objectiu del present treball és la traducció i l’anàlisi d’una publicació tècnica especialitzada sobre sistemes d’enllumenat, els quals han adquirit una rellevància notable, tant des del punt de vista arquitectònic de l’edifici, com des de la tecnologia de control lumínic que afavoreix l’estalvi energètic.