Papers by Silvia Kivatinitz
No existe consenso en el modo de predecir el rendimiento quesero. En la actualidad, las ecuacione... more No existe consenso en el modo de predecir el rendimiento quesero. En la actualidad, las ecuaciones disponibles se basan en un balance de masa de componentes que incluyen coeficientes de transferencia y/o retención de un componente en queso o suero, sin considerar desviaciones provocadas por las condiciones de procesamiento, siendo estas tan complejas y diversas que hacen imposible desarrollar un modelo matemático que incluya factores fisicoquímicos, tecnológicos y humanos. En el trabajo, se estudió el rendimiento quesero de queso Cremoso Argentino con datos provistos por la planta piloto de la ESIL situada en Villa María. Se modeló e implementó una red neuronal para predicción de rendimiento basado en datos de composición de la leche, comparando el rendimiento real y el predicho. Finalmente, se probó la capacidad de predicción del modelo desarrollado y su aplicación a nivel industrial, demostrándose su aptitud para obtener predicciones precisas de la dimensión Rendimiento Quesero.
Springer eBooks, 1987
The biosynthesis of brain gangliosides is now a process fairly well known. It is established that... more The biosynthesis of brain gangliosides is now a process fairly well known. It is established that the ceramide moiety is synthetized in the endoplasmic reticulum while the carbohydrate moiety is synthetized in the Golgi apparatus (Landa et al., 1981). The enzyme reactions so far known in this synthesis are all single additions of one sugar in a step wise manner. The flow chart of these reactions is accepted without serious arguments even if there is a paucity of information on the enzymes and the regulation of their activities. These enzyme reactions are carried out inside vesicles where the product gangliosides are protected from the activity of outside enzymes. Apparently at a certain stage of the synthetic process the enzyme activities or the donor substrates disappear and from this stage on the pattern of gangliosides for the target organ remains unchanged. Inside the vesicles the gangliosides are conveyed by axonal transport to the nerve ending (Forman and Ledeen 1972, Landa et al., 1979) and there they are deposited in the plasma membrane by a mechanism at present poorly understood. The most popular and perhaps the most sensible current theory is that they pass from inside the vesicles to the extraplasmatic layer of the plasma membrane by a mechanism of fusion but the difficulties to accept this concept are great as you will see further on.
Darwiniana, Dec 31, 2016
A melisopalynological study of 49 honeys samples from the northwest of Córdoba province was perfo... more A melisopalynological study of 49 honeys samples from the northwest of Córdoba province was performed. Prosopis spp., Larrea divaricata, Schinopsis spp., Condalia microphylla, Sarcomphalus mistol, Cercidium praecox, Geoffroea decorticans, Capparis atamisquea, Aloysia gratissima, Mimosa spp. and Schinus spp. were the most frequent and important pollen types, all of them correspond to native species. Four different groups were validated by the discriminant analysis, Traslasierra, Perisalina, Chaco Arido and Chaco Serrano, some species were proposed to differentiate between them: Schinus areira, Maytenus vitis-idaea, Cantinoa mutabilis and Schinopsis spp. respectively. Pollen types with the highest species importance index and frequencies are proposed as markers to be used in designation of origin.
Universidad Nacional de Córdoba, Mar 2, 2017
Darwiniana, nueva serie, 2016
A melisopalynological study of 49 honeys samples from the northwest of Córdoba province was perfo... more A melisopalynological study of 49 honeys samples from the northwest of Córdoba province was performed.
Prosopis spp., Larrea divaricata, Schinopsis spp., Condalia microphylla, Sarcomphalus mistol,
Cercidium praecox, Geoffroea decorticans, Capparis atamisquea, Aloysia gratissima, Mimosa spp. and
Schinus spp. were the most frequent and important pollen types, all of them correspond to native species.
Four different groups were validated by the discriminant analysis, Traslasierra, Perisalina, Chaco
Arido and Chaco Serrano, some species were proposed to differentiate between them: Schinus areira,
Maytenus vitis-idaea, Cantinoa mutabilis and Schinopsis spp. respectively. Pollen types with the highest
species importance index and frequencies are proposed as markers to be used in designation of origin.
Universidad Nacional de Córdoba, May 14, 2021
Universidad Nacional de Córdoba, May 14, 2021
Primera y segunda dimension de analisis transversal: Integracion interna (intrainstitucional) Int... more Primera y segunda dimension de analisis transversal: Integracion interna (intrainstitucional) Integracion con el medio (interinstitucional)
Lectura y firma del acta de la reunion anterior (previamente socializada por correo). Integracion... more Lectura y firma del acta de la reunion anterior (previamente socializada por correo). Integracion interna (intrainstitucional). Presentacion de los colaboradores de la SAA.
1. Revisar las ultimas sugerencias recibidas (de Di Paola y Arias). 2. Firmar el Acuerdo General ... more 1. Revisar las ultimas sugerencias recibidas (de Di Paola y Arias). 2. Firmar el Acuerdo General e inclusion de disidencias si las hubiera. 3. Pautas de trabajo para las proximas dimensiones a analizar.
International Dairy Journal, 2016
β-Casein (β-CN), β-lactoglobulin (β-LG), and α-lactalbumin (α-LA), were subjected to UV irradiati... more β-Casein (β-CN), β-lactoglobulin (β-LG), and α-lactalbumin (α-LA), were subjected to UV irradiation, alone or in the presence of hydrogen peroxide, hydrogen peroxide plus copper, or iron. Disappearance of tryptophan (Trp) was fastest for α-LA and slowest for β-CN. Hydrogen peroxide accelerated loss of Trp, while addition of iron did not further increase the speed of Trp reduction, but the addition of copper did. Oxidation products were higher for β-CN than for β-LG following UV irradiation alone or in the presence of hydrogen peroxide or hydrogen peroxide plus iron. In the presence of copper, oxidation rates were similar for both proteins. UV photo-oxidation caused the loss of the native polypeptides, the rate of this being faster for β-LG than for β-CN. These results are compatible with the concept that formation of dityrosine and N-formylkynurenine were favoured by mobility in the native protein.
Mediante un instrumento de financiamiento del Ministerio de Ciencia, Tecnologia e Innovacion Prod... more Mediante un instrumento de financiamiento del Ministerio de Ciencia, Tecnologia e Innovacion Productiva, nuestro grupo de investigacion obtuvo el financiamiento para el PFIP: “Desarrollo y fortalecimiento de laboratorio para la determinacion del origen botanico, caracterizacion fisica, quimica y microbiologica de miel producida en Catamarca”. El mismo esta en ejecucion y tiene como objetivo principal conocer, y dar a conocer, la calidad de las mieles que se producen en Catamarca mediante la valoracion de diferentes indicadores que rigen el comercio de este alimento. Se persigue complementar el conocimiento de campo y experiencia del apicultor con los saberes analiticos y cientificos inherentes a la clase y calidad del producto en cuestion, contribuyendo de esta manera a poner en valor un producto obtenido artesanalmente. Del dialogo generado entre los actores involucrados: productores, cientificos, y gestores provinciales y nacionales, devino una fertil vinculacion que enriquecio lo...
Se estudió la regulación del receptor de lipoproteína de muy baja densidad (VLDLR) en dos tipos d... more Se estudió la regulación del receptor de lipoproteína de muy baja densidad (VLDLR) en dos tipos de células que intervienen en la respuesta inflamatoria: hepatocitos (HepG2) y células linfocitarias de bazo de ratón (CMB) por agentes implicados en la inflamación: VLDL o Gemfibrozil, lipopolisacárido bacteriano (LPS) para HepG2 o Concanavalina A (ConA) para CMB. Se determinaron por citometría de flujo las subpoblaciones de CMB y de HepG2 en distintas fases del ciclo celular (G1 y G2/M) con ioduro de propidio y las VLDLR+ con VLDL fluorescente. Entre 10 a 60 por ciento de células expresaron VLDLR dependiendo de las condiciones experimentales. El enfrentamiento con LPS o ConA produjo un aumento de células VLDLR+. El tratamiento con Gemfibrozil disminuyó el número de hepatocitos en reposo VLDLR+ pero incrementó significativamente (más de dos veces) los hepatocitos VLDLR+ en fase G2/M. En los cultivos de CMB Gemfibrozil aumentó por igual el porcentaje de células VLDLR+ quiescentes y en G2/M. El comportamiento de estos tipos celulares con VLDL fue distinto: CMB no mostró cambios en las subpoblaciones VLDLR+, los hepatocitos mostraron disminución de VLDLR+ tanto en fase G1 como en fase G2/M. Se concluyó que el estudio de la regulación de VLDLR en distintas células facilitará el diseño de fármacos específicos para el tratamiento de enfermedades de etiología inflamatoria. Palabras clave: inflamación * lipoproteínas * receptor de lipoproteína de muy baja densidad * Gemfibrozil Summary The regulation of the VLDL receptor (VLDLR) by molecules involved in the inflammation process (lipopolysaccharide, LPS; Concanavalin A, ConA, VLDL or Gemfibrozil) in two cellular types implied in the inflammatory response, hepatocytes (HepG2) and lymphocitary cells from mice spleen (CMB), was studied. Different subpopulations of CMB and HepG2 in different cell cycle phases (G1 and G2/M) were analyzed using flow citometry
J Neurochem, 2002
We have previously described a thermostable inhibitor of the UDP-N-acetylgalactosamine:GM3,N-acet... more We have previously described a thermostable inhibitor of the UDP-N-acetylgalactosamine:GM3,N-acetylgalactosaminyltransferase (GM2 synthase) purified from chicken blood serum. Some properties of the GM2 synthase inhibitory preparation (IP) resemble those of high-density lipoprotein (HDL), i.e., both have a MW of 200,000 in native conditions and are resistant to denaturation by heat. These and other facts prompted us to test the possibility that lipoproteins regulate ganglioside biosynthesis in the CNS. For this purpose, serum lipoprotein fractions were isolated from chicken serum by flotation and were assayed as inhibitors of GM2 synthase activity and of neuron differentiation in culture. HDL (in contrast to fractions containing very low-density or low-density lipoprotein) inhibited GM2 synthase with the same specific activity as IP and inhibited neuron cell differentiation in culture in a similar way. Furthermore, these two preparations also share several other characteristics; i.e., both have the same cholesterol content, the same floating behavior on KBr gradients, and the same polypeptide pattern as detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and staining with Coomassie Blue, or after western blot and revealing with an antibody prepared against IP, which is able to diminish the inhibitory effect of this preparation. The results described indicate identity between HDL and IP and suggest that HDL (particularly apolipoprotein A) could play an important role on ganglioside biosynthesis modulation during CNS development. The antineuritogenic effect of HDL described in this study could be of physiological relevance during CNS development and response to injury.
Http Dx Doi Org 10 1080 00173134 2013 819525, Aug 25, 2013
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Papers by Silvia Kivatinitz
Prosopis spp., Larrea divaricata, Schinopsis spp., Condalia microphylla, Sarcomphalus mistol,
Cercidium praecox, Geoffroea decorticans, Capparis atamisquea, Aloysia gratissima, Mimosa spp. and
Schinus spp. were the most frequent and important pollen types, all of them correspond to native species.
Four different groups were validated by the discriminant analysis, Traslasierra, Perisalina, Chaco
Arido and Chaco Serrano, some species were proposed to differentiate between them: Schinus areira,
Maytenus vitis-idaea, Cantinoa mutabilis and Schinopsis spp. respectively. Pollen types with the highest
species importance index and frequencies are proposed as markers to be used in designation of origin.
Prosopis spp., Larrea divaricata, Schinopsis spp., Condalia microphylla, Sarcomphalus mistol,
Cercidium praecox, Geoffroea decorticans, Capparis atamisquea, Aloysia gratissima, Mimosa spp. and
Schinus spp. were the most frequent and important pollen types, all of them correspond to native species.
Four different groups were validated by the discriminant analysis, Traslasierra, Perisalina, Chaco
Arido and Chaco Serrano, some species were proposed to differentiate between them: Schinus areira,
Maytenus vitis-idaea, Cantinoa mutabilis and Schinopsis spp. respectively. Pollen types with the highest
species importance index and frequencies are proposed as markers to be used in designation of origin.