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Search Results: 1 - 10 of 202618 matches for " Erika Elizabeth;Rivas-Díaz "
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Comparación del contenido fenólico, capacidad antioxidante y actividad antiinflamatoria de infusiones herbales comerciales
Mu?oz-Velázquez, Erika Elizabeth;Rivas-Díaz, Karla;Loarca-Pi?a, Ma. Guadalupe Flavia;Mendoza-Díaz, Sandra;Reynoso-Camacho, Rosalía;Ramos-Gómez, Minerva;
Revista mexicana de ciencias agrícolas , 2012,
Abstract: actually there is an increase on infusion consumption due their beneficial properties, which are attributable to the presence of phenolic compounds. by this reason, the aim of this study was to assess phenolic content, antioxidant capacity and anti-inflammatory capacity of commercial infusions of peppermint (mentha piperita l.), lemon grass (cymbopogon citratos), chamomile (matricaria chamomilla l.), arnica (heterotheca inuloides) and boldo (peumus boldus molina) obtained in supermarket in 2009. phenols content and antioxidant capacity were defined by spectrophotometry techniques. also, identification and quantification of phenolic compound was made by hplc. the anti-inflammatory activity was assessed by inhibition of ciclooxigenasa-2 (cox-2) enzyme. boldo infusion had greatest content of phenolic compounds and greater antioxidant capacity measured by abt techniques, followed by chamomile infusions by frap method. in assessed infusions ten different compounds were identified, finding in higher concentration the compounds catechin, epigallocatechin gallate, rosmarinic acid and eriocitrin. as for inhibitory capacity on cox-2, chamomile and lemon samples had higher percentages of inhibition, followed by boldo infusion. in general, results suggest that boldo and peppermint commercial infusions show biological properties with potential benefits for health.
Molecular cloning and expression of a putative crustacean hyperglycemic hormone of Litopenaeus vannamei in Pichia pastoris
Sánchez-Castrejón,Edna; Ponce-Rivas,Elizabeth; Aguilar,Manuel B; Díaz,Fernando;
Electronic Journal of Biotechnology , 2008,
Abstract: crustacean hyperglycemic hormone (chh) is the most abundant and best studied member of the chh/mih/gih neuropeptide hormone family. chh plays a major role in controlling glucose levels in the hemolymph, and it also has significance in regulating molting, reproduction, and osmoregulation. in contrast, molt-inhibiting hormone (mih) is responsible for maintaining animals in an intermolt stage. in this study, liv-mih-1 cdna, which encodes a mature neuropeptide from the eyestalk of white shrimp, litopenaeus vannamei, was expressed in methylotrophic yeast (pichia pastoris km71) under the control of an alcohol oxidase promoter. recombinant liv-mih-1 was secreted into the culture medium using the α-factor prepro-sequence without glu-ala repeats. the expected protein, which had an apparent molecular mass of 12.1 kda, was detected by tricine-sds-page analysis and confirmed by western blot. pure recombinant liv-mih-1 was obtained by affinity chromatography, and n-terminal sequence analysis confirmed expression of the protein. biological assays for chh and mih activity were also performed. purified recombinant liv-mih-1 showed the ability to elevate the glucose level of hemolymph of l. vannamei, but molting was unaffected. since these results are in agreement with the high structural and phylogenetic similarity that has been observed between liv-mih-1 and other chh neuropeptides we propose to rename the protein liv-chh-sg1.
Symmetric Boolean Algebras
R. Díaz and M. Rivas
ACTA MATHEMATICA UNIVERSITATIS COMENIANAE , 2010,
Abstract: In order to study Boolean algebras in the category of vector spaces we introduce a prop whose algebras in set are Boolean algebras. A probabilistic logical interpretation for linear Boolean algebras is provided. An advantage of defining Boolean algebras in the linear category is that we are able to study its symmetric powers. We give explicit formulae for products in symmetric and cyclic Boolean algebras of various dimensions and formulate symmetric forms of the inclusion-exclusion principle.
Symmetric Boolean Algebras
R. Díaz,M. Rivas
ACTA MATHEMATICA UNIVERSITATIS COMENIANAE , 2010,
Abstract: In order to study Boolean algebras in the category of vector spaces we introduce a prop whose algebras in set are Boolean algebras. A probabilistic logical interpretation for linear Boolean algebras is provided. An advantage of defining Boolean algebras in the linear category is that we are able to study its symmetric powers. We give explicit formulae for products in symmetric and cyclic Boolean algebras of various dimensions and formulate symmetric forms of the inclusion-exclusion principle.
Correlación entre la radiografía de tórax y el ecocardiograma para la valoración de cardiomegalia en pacientes con hipertensión arterial sistémica
Díaz Arrieta, Gustavo;Mendoza Hernández, María Elsa;Hernández Cabrera, Jorge;Robles Parra, Héctor Manuel;Espinosa Vázquez, Raúl Arturo;Pacheco Aranda, Erika;Rivas Duro, Miguel;Domínguez Herrera, Javier Guillermo;Sánchez Velázquez, Luis David;Ramírez Torres, Marco Antonio;Sánchez Maravillas, Juana;Ortega Alvarado, Silvia Alejandra;
Archivos de cardiología de México , 2006,
Abstract: the chest radiography is used routinely by the clinician as a tool in the scan of patients with systemic arterial hypertension (sah) to evaluate the dimensions of the heart. however the highest reported sensitivity forthe evaluation of heart growth with this method is 77.3% in contrast to the transthoracic echocardiogram (tte) that reaches between 90 to 100%. the aim of this study was assess in our population of patients with sah, the correlation between chest radiography and the tte in regard to cardiomegaly. patients and methods: seventy two patients with sah and radiological cardiomegaly, graded by measuring the cardiothoracic ratio (ctr), were evaluated by transthoracic echocardiography.the pearson's and spearman's correlation coefficients between both methods were assessed. significance level was set at < 0.05. results: forty one (56.9%) patients were women and 31 (43.1%) were men. the age was 62.4 ± 10 years (43-83 years). left ventricular concentric hypertrophy (lvch) was found in 56 (77.8%) patients. in 13 (18%) patients the left ventricular end diastolic diameter (lvedd) was higher than the normal value. the correlation coefficient between the diastolic ventricular septal thickness (dst) and ctr was 0.285 (p < 0.05) and between the lvedd and radiological cardiomegaly was 0.203 (p = ns). conclusions: in patients with sah, the radiological evidence of cardiomegaly keeps a correlation with ventricular hypertrophy, but not with ventricular dilation.
Efecto de la suplementación con Saccharomyces cerevisiae sobre la producción de leche al inicio de la lactancia en vacas lecheras
Rivas,Jose; Díaz,Thais; Hahn,Martin; Bastidas,Pedro;
Zootecnia Tropical , 2008,
Abstract: the aim of this study was to determine the strategic use of saccharomyces cerevisiae (sc) from onset of lactation and its effect on milk and fat production in holstein (h) and carora (c) cows located in the mountain area of merida state, venezuela. forty-one h and fifteen c cows were assigned to two treatments: experimental group (eg; h=22 and c=8) fed with 10 g/d of sc and control group (cg; h=19 and c=7), which did not received any supplement for a period of 105 d postpartum (dpp). carora cows grazed pastures of panicum maximum, whereas h cows had access to pastures of pennisetum clandestinum. all cows were fed at milking with a concentrate mixture (20% cp and 77% tnd) at a ratio of 1 kg:3 kg of milk. milk production was measured weekly during 15 weeks and fat milk during the first six weeks post calving. data were analyzed by least squares means and comparison of subclass means were tested for significance using tukey′s procedures. milk yield was increased (p < 0.05) in h fed with sc, having 165 kg more of accumulated milk yield at 105 dpp than the cg. also h cows with three or more calvings had higher (p<0.01) accumulated milk yield at 105 dpp (2544.6 ± 84.9 kg) than cows with 1 or 2 calvings (1916 ± 122.4 and 2227.7± 67.9 kg, respectively). there was not a treatment effect in milk yield in c cows. in holstein cows treated with sc, the accumulated milk fat at six weeks postcalving was 3.4 kg greater compared to cg (35.5 ± 1.4 vs 32.0 ± 1.6 kg, respectively). results from this study indicate that the strategic use of sc during the first 105 dpp, improved milk and fat yield in dairy cows perhaps by stimulating the action of yeast culture in the rumen and the availability of nutrients for the mammary gland.
Obtaining More Realistic Cross-Layer QoS Measurements: A VoIP over LTE Use Case
F. Javier Rivas,Almudena Díaz,Pedro Merino
Journal of Computer Networks and Communications , 2013, DOI: 10.1155/2013/405858
Abstract: We introduce a real-time experimentation testbed in this paper which enables more realistic analysis of quality of service (QoS) in LTE networks. This testbed is envisioned for the improvement of QoS and quality of experience (QoE) through the experimentation with real devices, services, and radio configurations. Radio configurations suggested in the literature typically arise from simulations; the testbed provides a real and controlled testing environment where such configurations can be validated. The added value of this testbed goes a long way not only in the provision of more realistic results but also in the provision of QoS and QoE cross-layer measurements through the correlation of information collected at different layers: from service and IP levels to radio and protocol parameters. Analyzing the interlayer dependencies will allow us to identify optimal settings for the radio access network and service parameters. This information can be used to suggest new cross-layer optimizations to further improve quality of experience of mobile subscribers. As a use case, we examine VoIP service over LTE, which is currently an open issue. 1. Introduction The enhancement of QoS in a sustainable manner is a critical goal for network operators as management tasks are becoming increasingly complex. Although some initial efforts have been carried out by the standardization bodies, there is still a significant gap to be covered in QoS and also in QoE optimization. Actually, current efforts towards improving QoS and QoE are typically based on estimations derived from costly drive test campaigns. Furthermore, involvement of human expertise is required to manually tune network configurations. On the other hand, most of the service and network configurations available in the literature are derived from simulations [1–6]. As is widely known, in the process of modeling communication systems to simulate them, some details may be missed, and thus, misleading results may be derived. For example, it is very common to find that the consumption of control resources is ignored when evaluating different scheduling methods. In this context, providing optimized network configurations based on measurements obtained directly from the subscribers' terminals and correlated with the information collected at the network will pave the way for a reduction of costs and more accurate tuning of network operation from the point of view of the QoS perceived by final users. Moreover, as stated by standards organizations (SDOs) or alliances with the participation of network operators such as
Evaluation of the adhesion to the vaccunation scheme regime mass immunization plan in Clinica Infantil Colsubsidio
Ausberto Pardo Reyes, MD,Erika Janneth Cardoso Rodríguez,Sergio Alejandro Díaz Cediel,Lady Lorena Díaz Medina
Revista Ciencias de la Salud , 2007,
Abstract: Background. The human being has tried tofind solid protection against infectious diseases,hence, vaccination was sought as the most important milestone public health intervention forcommunicable diseases. In this context, and injoint action with world nations, the MassImmmunization Plan was created in order toreach the control and eradication of the abovementioned diseases.Materials and Methods. A descriptive, retrospectivestudy was conducted. Primary datawas drawn from children under 6-year-old ofage as users of the program of Promotion, Educationand Prevention (PEP) at the Clínica InfantilColsubsidio in Bogotá, Colombia, and those attendedat the vaccination center of the abovementioned institution between January 1 andDecember 31, 2005.Results. 7.686 children under 6-year-oldwere registered in the information data base atthe Vaccination Center of Clínica InfantilColsubsidio. 65,75 % complied with the vaccinationscheme regimen according to age,whereas 34,23 % had still an incomplete schemeregimen. Children between 6 months and 2 yearsof age represent the most affected group withincomplete scheme regimen (19,87 %). 30.984was the total amount of vaccines applied duringthis specific period.Conclusions. This preliminary study showfigures which raise concern dealing vaccinationcoverage. However, shows existing failure tofulfill comprehensive vaccination scheme regime,besides the need of forther strengtheningthe program of promotion, education and preventionPEP that is realized at the health networkof Colsubsidio.
Inmunodiagnóstico en Didelphis marsupialis usando un antígeno de Paragonimus de Venezuela Immunodiagnostic in Didelphis marsupialis using an antigen of Venezuelan Paragonimus
Erika Gómez Martínez,Zoraida Díaz-Bello,Reinaldo Zavala-Jaspe,Marcos Tulio Díaz
Acta bioqu?-mica cl?-nica latinoamericana , 2010,
Abstract: Los Paragonimus son trematodos que habitualmente viven en los pulmones de mamíferos carnívoros y omnívoros, entre ellos el hombre. En el oriente venezolano se encuentra el único foco de Paragonimus sp. donde Didelphis marsupialis es el único reservorio demostrado hasta ahora. Con el fin de tener herramientas de inmunodiagnóstico que detecten la presencia de Paragonimus sp. en esta especie, se elaboraron varios reactivos para realizar un ensayo inmunoenzimático ELISA. Entre ellos se obtuvo un antígeno crudo soluble de vermes adultos de Paragonimus y una inmunoglobulina de gallina anti-IgG de Didelphis marsupialis. Los mismos se capturaron en la localidad de Aguas Blancas, municipio Montes, estado Sucre, Venezuela, y se obtuvieron muestras sanguíneas; en el caso de estar infectados, los vermes adultos se extrajeron del pulmón. Los parásitos se homogenizaron y ultracentrifugaron para obtener la fracción soluble del parásito (FSPA) como antígeno para el ELISA y Western blot y detectar los anticuerpos en los Didelphis marsupialis. El análisis electroforético mostró 22 moléculas entre 6 y 82 kDa; por Western blot se presentó un reconocimiento antigénico de 8 moléculas siendo las de 112 kDa y 268 kDa las más reconocidas por los sueros positivos. Los sueros negativos no reconocieron ninguna proteína. La producción de IgY en gallinas permitió desarrollar las técnicas de inmunodiagnóstico para la búsqueda de anticuerpos específicos anti-Paragonimus sp. en Didelphis, cuya aplicación permitirá establecer la vigilancia epidemiológica de estos reservorios en áreas endémicas sin sacrificio de los mismos. Paragonimus are trematodes that normally live in the lungs of carnivorous and omnivorous mammals such as humans. An outbreak of Paragonimus sp. in which Didelphis marsupialis was the only wild reservoir incriminated was described in eastern Venezuela. In order to have immunological tools to detect the presence of Paragonimus sp. in this reservoir, a whole antigen of the adult worm of this parasite was elaborated. Didelphis marsupialis were captured in the locality of Aguas Blancas, Montes municipality, Sucre state, Venezuela, from which blood samples were obtained and a search for worms was performed in lungs. Worms were homogenized and ultracentrifugated to obtain FSPA to perform immunoassay (ELISA) to detect antibodies in opossums. The electrophoresis analysis showed a pattern of 22 molecules between 6 and 82 kDa; by western blot, the antigenic recognition of 8 antigenic molecules appeared,112 kDa and 268 kDa molecules being the most strongly recognized by positive
Efecto de la salinidad sobre la fisiología energética del camarón blanco Litopenaeus vannamei (Boone)
Valdez, Gustavo;Díaz, Fernando;Re, Ana Denisse;Sierra, Elizabeth;
Hidrobiológica , 2008,
Abstract: the energy balance was determined with in litopenaeus vannamei, juveniles acclimated to salinity where they were hyperosmotic (20 ups), isosmotic (26 ups), and hypo-osmotic (32 ups). also o:n atomic ratio was calculated. the ingestion rate, oxygen consumption, ammonium excretion and scope for growth were affected significantly (p < 0.05) when the organisms were acclimated at 20, 26 and 32 ups. the highest energy contained from the food consumed was obtained in the organisms maintained in 26 ups. the lowest energy expense derived to routine metabolism, and excretion of nitrogenous products was obtained in the animals maintained at 26 ups. the high quantity of energy channeled to the scope for growth (671.1 j g-1 day-1 d.w.) was obtained in the shrimps acclimated to salinity of 26 ups. the o:n atomic ratio calculated for the juveniles indicated a catabolism of carbohydrates for the organisms maintained in the isosmotic condition. the apparent heat increment, the feces production, and energy lost by exuviae, not were significantly different (p > 0.05) in the shrimps exposed to the three salinities. we recommend maintaining litopenaeus vannamei juveniles at the salinity level which is isosmotic (26 ups), where they are free of environmental stress, these conditions for white shrimp juveniles would enhance production in the cultivation of this species.
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