oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 111 )

2019 ( 731 )

2018 ( 791 )

2017 ( 777 )

Custom range...

Search Results: 1 - 10 of 442848 matches for " Eleazar M. Escamilla-Silva "
All listed articles are free for downloading (OA Articles)
Page 1 /442848
Display every page Item
Optimization of Zeaxanthin Production by Immobilized Flavobacterium sp. Cells in Fluidized Bed Bioreactor  [PDF]
Ma Del Carmen Chavez-Parga, Alejandro Munguia-Franco, Mayanin Aguilar-Torres, Eleazar M. Escamilla-Silva
Advances in Microbiology (AiM) , 2012, DOI: 10.4236/aim.2012.24078
Abstract:

From time immemorial, human beings have used pigments made from vegetables, fruits, superior plants, animal tissues and cereals. One of the greatest sources of pigments is the bacterium that, with the use of the modern technology, has increased the production of metabolites of interest. The microbiological production of carotenoids has not been optimized to obtain pigment production quantities of pigments and carotenoids recovery that lower production costs. The aim of this work was to design a Zeaxanthin production process with Flavobacterium sp. immobilized cells in a fluidized bed bioreactor. An optimum culture medium for Zeaxanthin production in stirred flasks (2.46 g·L–1) was obtained. Furthermore, optimum process conditions for a maximum yield of Zeaxanthin production, by fluidized bed bioreactor, were established. A statistical analysis showed that the most significant factors were air flow, pH and NaCl concentration (4.5 g·L–1). In this study a maximum Zeaxanthin production of 3.8 g·L–1 was reached. The highest reported yield to date was 0.329 g·L–1.

El mito y el siglo veinte
Eleazar M. Meletinski
Entretextos : Revista Electronica Semestral de Estudios Semióticos de la Cultura , 2006,
Abstract:
Household Food Insecurity Is Not Associated with BMI for Age or Weight for Height among Brazilian Children Aged 0–60 Months
Gilberto Kac, Michael M. Schlüssel, Rafael Pérez-Escamilla, Gustavo Velásquez-Melendez, Ant?nio Augusto Moura da Silva
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0045747
Abstract: We examined the association between Household Food Insecurity (HFI), weight for height z-score (WHZ) and Body Mass Index for age z-score (BMI-Z) in a representative sample of children 0–60 months of age (n = 3,433) in five Brazilian geographical regions. Data were derived from the 2006–07 Brazilian Demographic and Health Survey. HFI was measured with the Brazilian Food Insecurity Scale. Associations were estimated using multiple linear regression models (? coefficients and 95% CI) taking into account the complex sampling design. Interaction terms between HFI and geographical region and HFI and child sex and child age were assessed. The weighted prevalence of any level of HFI was 48.6%. Severe food insecurity was more prevalent among children from the North region (16.8%), born from mothers with <4 years of schooling (15.9%) and those from families with ≥3 children (18.8%). The interaction between HFI and geographical region was non-significant for BMI-Z (P = 0.119) and WHZ (P = 0.198). Unadjusted results indicated that HFI was negatively associated with BMI-Z (moderate to severe HFI: ? = ?0.19, 95% CI: ?0.35 - ?0.03, P = 0.047), and WHZ (moderate to severe HFI: ? = ?0.26, 95% CI: ?0.42 - ?0.09, P = 0.009). Estimates lost significance after adjustments for key confounders such as mothers' skin color, mothers' years of schooling, place of household, household income quartiles, mothers' smoking habit, mothers' marital status, number of children 0–60 months in the household, and birth order. HFI is unrelated to weight outcomes among Brazilian children 0–60 months.
DETERMINACIóN DE PARáMETROS DE LA CONTAMINACIóN MICROBIANA PRESENTE EN UN áREA DE FABRICACIóN DE MEDICAMENTOS ESTéRILES A BASE DE ANTIBIóTICOS β -LACTáMICOS
J. Delgado,M. Escamilla,L. Pérez,A. Arias
Universitas Scientiarum , 2004,
Abstract: El presente trabajo muestra la evaluación, determinación y parametrización de la contaminación microbiológica generada por la elaboración de medicamentos estériles a base de antibióticos β -Lactámicos en una industria farmacéutica. Se establecen límites de contaminación antes, durante y después de la liberación del área mediante el análisis microbiológico del ambiente, superficies, equipos, sistemas de ventilación y uniformes de trabajo hasta establecer límites de confianza y niveles de aceptación de cada una de las zonas del área para cumplir con las normas nacionales exigidas por la entidad gubernamental reguladora de los laboratorios farmacéuticos en Colombia, Instituto Nacional de Vigilancia de Medicamentos y Alimentos (INVIMA).Mediante el análisis microbiológico de los parámetros evaluados se determinó el número y clase de microorganismos presentes en el área, llegando a una completa identificación de éstos, aislando las siguientes cepas bacterianas: Micrococcus kristinae y Staphylococcus xylosus y Aspergillus fumigatus.Finalmente, se estableció un programa de monitoreo microbiológico ambiental con la evaluación de todos los parámetros que componen y están implícitos en el área asegurando y soportando su continuidad con la documentación y registros elaborados para el área estéril de antibióticos β -Lactámicos.
Efecto de la sacarosa en la producción de celulosa por Gluconacetobacter xylinus en cultivo estático
Rubén Jaramillo L.,Wladimir Tobio J.,José Escamilla M.
Revista MVZ Córdoba , 2012,
Abstract: Objetivo. Determinar el efecto de sacarosa en la productividad de BC por Gluconacetobacter xylinus IFO 13693 en condición estática. Materiales y métodos. La síntesis de celulosa bacteriana (BC) por Gluconacetobacter xylinus se llevo a cabo en un cultivo estático discontinuo a temperatura ambiente, en presencia de sacarosa como la principal fuente de carbono a concentraciones iniciales de 0.8 a 7.6 % (p/v). Las concentraciones remanentes de BC, sacarosa, glucosa y fructosa se determinaron cada semana. Para la cinética de la hidrólisis de la sacarosa y formación de celulosa y el coeficiente de rendimiento del producto se utilizo el software Microcal Origin 6.0 . Resultados. En la cuarta semana los valores de BC se encontraron entre 32.5 a 39.5 g/L para las diferentes concentraciones de sacarosa. La cinética para la hidrólisis de sacarosa se ajusta al modelo de Michaelis-Menten, con una Vmax de 0.0002 mol L-1 h-1 y Km de 0.018 M. La producción de BC se ajusta al modelo propuesto por Marx-Figini y Pion, con un valor de la pendiente (kc), entre 0.0018 y 0.0024 h-1 para las diferentes concentraciones iniciales de sacarosa. Los coeficientes de rendimiento tienen valores de 0.8 a 2.4 g de BC producida/g de sacarosa consumida. Conclusiones. La hidrólisis de sacarosa, el consumo de glucosa y fructosa se refleja en la síntesis de celulosa. La hidrólisis de sacarosa y la producción de BC se ajustan a los modelos de Michaelis-Menten y al propuesto por Marx-Figini y Pion, respectivamente. Finalmente, el rendimiento depende de la concentración de sacarosa.
Albert Renold Memorial Lecture: Molecular Background of Nutritionally Induced Insulin Resistance Leading to Type 2 Diabetes – From Animal Models to Humans
Eleazar Shafrir
Experimental Diabetes Research , 2001, DOI: 10.1155/edr.2001.299
Abstract: Albert Renold strived to gain insight into the abnormalities of human diabetes by defining the pathophysiology of the disease peculiar to a given animal. He investigated the Israeli desert-derived spiny mice (Acomys cahirinus), which became obese on fat-rich seed diet. After a few months hyperplasia and hypertrophy of β-cells occurred leading to a sudden rupture, insulin loss and ketosis. Spiny mice were low insulin responders, which is probably a characteristic of certain desert animals, protecting against insulin oversecretion when placed on an abundant diet. We have compared the response to overstimulation of several mutant diabetic species and nutritionally induced nonmutant animals when placed on affluent diet. Some endowed with resilient β-cells sustain long-lasting oversecretion, compensating for the insulin resistance, without lapsing into overt diabetes. Some with labile beta cells exhibit apoptosis and lose their capacity of coping with insulin resistance after a relatively short period. The wide spectrum of response to insulin resistance among different diabetes prone species seems to represent the varying response of human beta cells among the populations. In search for the molecular background of insulin resistance resulting from overnutrition we have studied the Israeli desert gerbil Psammomys obesus (sand rat), which progresses through hyperinsulinemia, followed by hyperglycemia and irreversible beta cell loss. Insulin resistance was found to be the outcome of reduced activation of muscle insulin receptor tyrosine kinase by insulin, in association with diminished GLUT4 protein and DNA content and overexpression of PKC isoenzymes, notably of PKCε. This overexpression and translocation to the membrane was discernible even prior to hyperinsulinemia and may reflect the propensity to diabetes in nondiabetic species and represent a marker for preventive action. By promoting the phosphorylation of serine/threonine residues on certain proteins of the insulin signaling pathway, PKCε exerts a negative feedback on insulin action. PKCε was also found to attenuate the activity of PKB and to promote the degradation of insulin receptor, as determined by co-incubation in HEK 293 cells. PKCε overexpression was related to the rise in muscle diacylglycerol and lipid content, which are prevalent on lascivious nutrition especially if fat-rich. Thus, Psammomys illustrates the probable antecedents of the development of worldwide diabetes epidemic in human populations emerging from food scarcity to nutritional affluence, inappriopriate to their metabolic capacity.
Non heart-beating donors in England
Chaib, Eleazar;
Clinics , 2008, DOI: 10.1590/S1807-59322008000100020
Abstract: when transplantation started all organs were retrieved from patients immediately after cardio-respiratory arrest, i.e. from nonheart-beating donors. after the recognition that death resulted from irreversible damage to the brainstem, organ retrieval rapidly switched to patients certified dead after brainstem testing. these heart-beating-donors have become the principal source of organs for transplantation for the last 30 years. the number of heart-beating-donors are declining and this is likely to continue, therefore cadaveric organs from non-heart-beating donor offers a large potential of resources for organ transplantation. the aim of this study is to examine clinical outcomes of non-heart-beating donors in the past 10 years in the uk as an way of decreasing pressure in the huge waiting list for organs transplantation.
Contribution of animal models to the research of the causes of diabetes
Eleazar Shafrir
World Journal of Diabetes , 2010,
Abstract: In most publications, animal models of diabetes have mainly been investigated for their multiple etiologies as well as for changes leading to diabetes and their genetic derivation. Aspects which seem important and need a special research endeavor are the mechanism of the causes of diabetes and the lapse into complications in different species, their molecular basis and possible arrest and prevention. A concise list and and short discussion of the intensively studied rodents is presented of spontaneous or nutritional background causing Type 2 diabetes but omitting diabetes evoked by transgenic manipulations or gene knockout techniques.
The transmission of Rabbi Moses Arragel: Maqueda, Paris, London
Gutwirth, Eleazar
Sefarad : Revista de Estudios Hebraicos y Sefardíes , 2003,
Abstract: Rabbi Moshe Arragel and other scholars composed in the years 1422-30/33 the Arragel Bible. It is an extensive work that includes several texts in at least five different genres, as well as more than three hundred illuminations. Scholarly research on this medieval codex has been carried out now for more than one century. It is therefore possible today to analyse and investigate some of the factors that define its particularities, traditions and changes. Political interests, institutional or scholarly traditions and technological changes are factors that determine this kind of studies. Attention is drawn to: a) issues of technological reproduction (photolithography or facsimile industry) in determining criticism, and b) the role played by institutions (such as the Roxburghe Club) in the making of knowledge. La Biblia de Arragel es el resultado del trabajo de Rabbi Moshe Arragel y de otros durante el periodo 1422-30/33. Se trata de un códice extenso que incluye textos en al menos cinco géneros diferentes, así como más de trescientas miniaturas. La investigación sobre esta obra medieval tiene ya más de un siglo. Hoy en día, por tanto, es posible analizar esta historia e indagar acerca de algunos de los factores que determinan sus peculiaridades, tradiciones y cambios. Apropiaciones políticas, tradiciones institucionales o disciplinarias, y cambios tecnológicos son factores que determinan esta clase de estudios. Así, además de se alar algunos aspectos relevantes de la historia de la investigación, se presta también atención a: a) el problema de la relación entre crítica y tecnologías de reproducción (fotolitografía, industria del facsímil); y b) el marco institucional (historia del Roxburghe Club) y su papel en la producción del saber.
Pesados: Hospitality, Tedium and the Footsteps of Al-Andalus
Gutwirth, Eleazar
Sefarad : Revista de Estudios Hebraicos y Sefardíes , 2006,
Abstract: The transmission, translation and recreation of ancient and medieval ideas are one aspect of Hispano-Jewish Culture which is generally accepted in histories of philosophy, science, literature, religion. In some cases the “links” (Greek, Syriac, Arabic, Hebrew, Romance, etc.) in this chain of transmission are relatively well documented. In others the evidence to substantiate hypotheses of continuity is yet to be discovered. In between these poles there is a range of possibilities and different states of research. In the following lines an attempt will be made to argue that there is such a chain operating in the fields ofwisdom and literature (metered poetry, rhymed prose). This can be observed in a precise case: That of the development of the theme of the pesado. La transmisión, la traducción y la recreación de ideas de la Antigüedad son un aspecto de la cultura hispano-judía medieval que ha sido aceptada generalmente en las historias de la filosofía, la ciencia, la literatura o la religión. En algunos casos, los eslabones en la cadena de transmisión han sido relativamente bien documentados. En otros, es preciso aún sustanciar ciertas hipótesis de continuidad. Entre ambos extremos se sitúa una amplia gama de posibilidades y diferentes niveles de investigación. En este artículo se muestra que una cadena de transmisión funciona en el campo de la literatura sapiencial, como puede observarse en un caso preciso, el del desarrollo del tema del pesado.
Page 1 /442848
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.