Novel role for histamine through classical h1 and h2 receptors: regulation of leydig cell steroidogenesis and its implications for male reproductive function
Mondillo, Carolina; Pignataro, Omar Pedro
Most of the physiological functions of HA described to date have been linked to the well-characterized H1 and H2 receptors. Nevertheless, extensive research is continuously going on to elucidate new roles for these receptors. In this respect, recent reports have indicated expression of H1 and H2 receptors in germinal and peritubular cells of the testis, as well as in macrophages and Leydig cells. Interestingly, HA plays a role as autocrine/paracrine modulator of Leydig cell steroidogenesis in several experimental models, both in vivo and in vitro. It was demonstrated very recently that this modulatory effect is concentration-dependent and biphasic: while H1 receptor activation would be responsible for HA-mediated negative modulation of steroidogenesis, H2 receptor activation would lead to stimulation of steroid synthesis. Because antihistamine drugs target HA receptors, the novel role of HA as modulator of testicular steroidogenesis will surely attract more attention to possible unexpected side-effects of such drugs, which might alter the local balance and in turn enhance or decrease androgen production. Considering that HA has been implicated in spermatogenesis, penile erection and sexual behavior as well as steroidogenesis, it appears that the amine plays an integral role in the regulation of male reproductive functions which certainly deserves further investigation. C.
Las situaciones de juego: una matríz para desarrollo infantil
Rosemberg, Celia Renata
En este trabajo se analizan situaciones de juego en el jardín de infantes y en el medio familiar. Se considera el impacto que estas situaciones pueden tener en el desarrollo del lenguaje y el desarrollo cognitivo. La textura de las situaciones de juego es tanto lingüística como también no lingüística: las acciones que implica el juego están acompañadas y posibilitadas por lo significados y las comprensiones compartidas, que los participantes elaboran a partir de gestos, miradas y de la orientación y la posición de su cuerpo y no solo a partir del lenguaje. Estos aspectos no verbales configuran una matriz para el lenguaje; una matriz en la que, progresivamente, los usos infantiles del lenguaje se van desarrollando. El análisis realizado muestra a las situaciones de juego como situaciones de enseñanza informal; en las que los niños aprenden y usan formas lingüísticas cada vez más complejas.
Novel Applications of Polysaccharides from Lactic Acid Bacteria: A Focus on Kefiran
Abraham, Analia Graciela; Medrano, Micaela; Piermaria, Judith Araceli; Mozzi, Fernanda Beatriz
The food industry is constantly searching for new food components to improve the texture and mouth-feel of food products; moreover, health-promoting capacity of food ingredients is also desirable. In recent years, exopolysaccharide (EPS)-producing lactic acid bacteria (LAB) have gained attention due to their major role in functional f oods and for improving the sensorial properties of fermented products. Certain LAB excrete a wide diversity of polysaccharides with respect to their monomer composition, molecular weight (MW), structure, and functionalities. These extracellular components or EPS can impart functional properties to food and additionally, may confer beneficial health-promoting properties. The role of EPS from LAB in the dairy food industry (i.e. fermented milks and cheeses) is well documented. Also, the addition of EPSproducing LAB to cereal products or their use as food additives have been successfully applied thus broadening their field of application. Kefiran, a high-MW EPS produced by microorganisms present in the grains of the fermented milk kefir, has displayed novel applications in the food industry. Kefiran, which has a Newtonian behaviour in diluted solutions but pseudoplastic at high concentrations, improves the viscosity and viscoelastic properties of acid milk gels. This EPS is also able to form gels at low temperatures in addition to brittle and rigid films. However, glycerol addition confers it extremely high elongation values, allowing comparable flexibilities to those of synthetic material. Moreover, several health-promoting properties of kefiran such as immuno modulation or epithelium protection have been reported . Furthermore, kefiran has the ability to antagonize biological activity of Bacillus cereus on Caco-2 cells thus providing new perspectives for the role of this bacterial EPS in functional foods.
The role of landscape structure on the abundance of a disease vector planthopper: a quantitative approach
Grilli, Mariano Pablo
Studies of patchily distributed insect populations have made clear the importance of host patch size and degree of isolation in determining the distribution of these populations. For such populations, patch connectivity will have an effect on patterns of patch occupancy and regional dynamics. In the present study we performed a series of observations to estimate the effect of landscape structure on the abundance of Delphacodes kuscheli (Homoptera: Delphacidae). Actively dispersing D. kuscheli individuals were collected in 19 sampling sites during the spring of 2004, using sticky traps placed at 2 m above ground level. Land use and landscape pattern was quantified, using Landsat 5 TM images for the area where each sampling site was placed. Four land use categories were considered in the analysis; winter pastures, winter cereals, perennial pasture and stubble. The spatial pattern analysis program FRAGSTATS was employed to estimate the patch area, patch proximity index and four class metrics for each of the sites where samples were taken. Partial Least Squares Regression analysis techniques were employed to relate the mean abundance of D. kuscheli and the landscape measures.Eighty-one percent of the variation of the mean insect abundance was explained by 54% variation of the landscape elements. The proximity index of the local host patches, the amount of area left to stubble, local host patch area and total area of winter pastures were the most important variables affecting the abundance of dispersing D. kuscheli individuals. We found that the abundance of the dispersive fraction of the population of D. kuscheli is affected mostly by the surrounding landscape, particularly by the proximity of other host patches, and the permeability of the matrix represented by the stubble.
Contemporary colonisation by waterbirds of a small dam lake in central Argentina
Nores, Manuel Alberto; Cerana, María Micaela
A population of 80 individuals of five waterbird species which arrived at a small dam in Alta Gracia City, Córdoba, Argentina was studied. Observations over 30 years enabled us to confirm that no waterbird populations had settled there previously. The 1.4-ha and 1.5-m deep lake (known as ‘‘Tajamar’’), was built by the Jesuits in the middle of 17th century to store water for irrigation. It contains submerged vegetation of Egeria densa and Chara sp. and areas of open water and also has some species of small fish. The numbers of waterbirds were recorded at varying intervals between 2005 and 2009. The breeding of White-winged Coot (Fulica leucoptera) and Pied-billed Grebe (Podilymbus podiceps) were documented in the Tajamar, as well as the extinction and re-colonisation of Pied-billed Grebe and an increase in the number of individuals by successive immigrations of the Neotropic Cormorant (Phalacrocorax olivaceus). We also constructed the time-line for species arriving and departing.
Costos de atención de la diabetes tipo 2 en Argentina: un análisis de sensibilidad probabilístico
Caporale, Joaquín; Gagliardino, Juan Jose
Estimar el costo incremental de atención de diabetes tipo 2 sin complicaciones en la Argentina. Utilizamos las guías ALAD y el UKPDS para identificar recursos por aplicar en Córdoba y Misiones, provincias de características socioeconómicas opuestas. La estimación de costos se hizo por microcosteo desde la perspectiva del financiador público y asumiendo como escenario comparador la situación de una provincia sin programa de diabetes. Se incluyó un análisis de sensibilidad probabilístico mediante simulación de Montecarlo para el número de consultas y prácticas, probabilidad de usar insulina, terapia combinada de hipertensión, cantidad anual de tiras reactivas y costos unitarios de todos los recursos.; To estimate the incremental healthcare cost of type 2 diabetes without complications in Argentina. UKPDS and ALAD guidelines were used to identify resources to be applied in Córdoba and Misiones, two Argentinean provinces with opposite socioeconomic characteristics. Microcosting techniques were employed to estimate this cost from a public payer perspective, taking a province without diabetes program as a comparative scenario. Probabilistic sensitivity analysis following Monte Carlo simulation was used to determine number of visits and practices, probability of insulin treatment, combination therapy for hypertension, annual number of test strips and unit cost of all resources. Results: The main component of the annual incremental cost per patient in both provinces was self-monitoring blood glucose (~50%), followed by treatment of hypertension, dyslipidemia and diabetes. The lowest corresponded to human resources (<5%). The annual individual incremental expenditure was 32% higher in Córdoba due to the pharmacological treatment of diabetes (> 90%).
Biología de la alimentación del espinero grande Phacellodomus ruber (aves: Furnariidae) en el valle de inundación del río Paraná, Argentina
Alessio, Viviana Graciela; Beltzer, Adolfo Hector
The objective was research the feeding biology of the Greater Thornbird, Phace-llodomus ruber in the floodplain Paraná River. We show the quali-quantitative analysis of thirteen (13) stomach contents. Captures and field observations were carried out at Carabajal Island (Santa Fe) as part of exploratory samples, on years 1981- 1991. The average of trophic diversity (H) was 1,74 and the accumulated trophic diversity (Hk) was 2,59. The results indicate a diet com-posed by 20 taxonomic entities (17 corresponded to the animal fraction; wile the remaining to the vegetal fraction). The values for the relative importance index (IRI) showed an omnivore diet where the Coleoptera were the main represented category, while the Arachnida, Lepidoptera and the seeds were the secondary categories. Trophic niche amplitude varied between 0,22 (spring); 0,78 (summer); 0,6 (autumm) and 0, 8 (winter). Alimentary efficiency (l´e) was 98%. Prey sizes ranged between 0,1 mm to > 8 mm, most of them captured early during the day (IF). The preference index showed a high selection for the forest (0,3) and the gallery forest (0,29). Phacellodomus ruber has an omnivorous diet, basically insectivorous, being included in the insectivorous bird’s guild with pecking and gleaning soil and foliage.
Lactobacillus casei/paracasei: aislamiento de mutantes espontáneos fagorresistentes para uso industrial
Capra, María Luján; Mercanti, Diego Javier; Reinheimer, Jorge Alberto; Quiberoni, Andrea del Lujan
ResumenLos fagos de bacterias probióticas son causa de enormes pérdidas económicas y severas limitaciones a las estrategias de control. En este trabajo se aislaron y caracterizaron mutantes de L. casei/paracasei empleando el primer fago L. paracasei aislado en Sudamérica en una planta industrial argentina. Se caracterizaron fenotipo (eficiencias de recuperación de resistentes verdaderos, estabilidad, resistencia frente a otros fagos específicos) y mecanismos de fagorresistencia (nivel de fagorresistencia, liberación espontánea de fagos virulentos, adsorción con y sin calcio). Se demostró que el aislamiento de mutantes espontáneos resistentes desde bacterias probióticas sensibles, resulta una alternativa válida para obtener cepas para rotar en procesos industriales. Summary Phage attacks to probiotic strains cause enormous economic losses and limit common control strategies. In this work, spontaneous bacteriophage insensitive mutants were isolated from sensitive L. casei/paracasei strains against the first Sudamerican L. paracasei phage isolated in an Argentinean dairy plant. Phage resistance phenotype (efficiency of phage-resistant recovery, stability, sensitivity against other specific phages) and phage resistance mechanisms (phage resistance level, spontaneous release of virulent phages, phage adsorption with or without cacium ions) were characterized. The isolation of spontaneous phage-resistant mutants, from sensitive probiotic bacteria, was demonstrated to be a useful tool to obtain strains to rotate in industrial processes.
Characterisation of proteolysis profile of Argentinean sheep cheeses made by two different production methods
Candioti, Mario César; Bergamini, Carina Viviana; Palma, Susana Beatriz; Busetti, Margarita; Meinardi, Carlos Alberto; Zalazar, Carlos Antonio
BACKGROUND: In this work the proteolysis profiles of Argentinean sheep cheeses made by two different production methods were studied in order to develop products with typical and defined features. Cheeses with a starter of Streptococcus thermophilus, curd cut to corn grain size, washed and heated to 43◦C (S cheeses) and cheeses with a mixed starter of Streptococcus thermophilus, Lactobacillus helveticus and Lactobacillus bulgaricus, curd cut to rice grain size, unwashed and heated to 47 ◦C (L cheeses) were manufactured. The cheeses were ripened at 12 ◦C and 80% relative humidity for 180 days and samples were taken throughout this period. RESULTS: Gross composition and primary proteolysis were similar for both types of cheeses. Streptococci counts diminished from 109 to 107 colony-forming units g−1 during ripening in both S and L cheeses. Lactobacilli counts in L cheeses decreased during ripening and disappeared at 180 days. L cheeses had significantly lower pH values and showed higher peptidolysis than S cheeses. Triangle sensory evaluation indicated important differences between the two types of cheeses. CONCLUSION: S cheeses had a low proteolysis level and a soft flavour, making them appropriate for consumption after a short ripening time. L cheeses had a higher proteolysis level and more intense sensory characteristics, making them appropriate for consumption after a longer ripening time.
Effects of neonatal exposure to bisphenol A on steroid regulation of vascular endothelial growth factor expression and endothelial cell proliferation in the adult rat uterus
Bosquiazzo, Veronica Lis; Varayoud, Jorgelina Guadalupe; Muñoz de Toro, Monica Milagros; Luque, Enrique Hugo; Ramos, Jorge Guillermo
Hormonally controlled vascular changes play a key role in endometrial development and in the differentiation process necessary for implantation. Vascular endothelial growth factor (VEGF) has emerged as one of the central regulators of the uterine vasculature. Hormonal perturbations during neonatal development may alter sex steroid-dependent regulation of VEGF and may ultimately affect fertility later in life. The aim of this study was to determine whether neonatal exposure to the environmental estrogenic chemical bisphenol A (BPA) affects the adult rat uterine response to hormonal stimuli. Newborn female rats were given s.c. injections of vehicle, BPA (0.05 mg/kg per day or 20 mg/kg per day) or diethylstilbestrol (0.2 μg/kg per day) on Postnatal Days 1, 3, 5, and 7. To evaluate the long-term effects, rats were ovariectomized at Postnatal Day 80 and submitted to hormonal replacement. Rats neonatally exposed to xenoestrogens showed a decreased induction of uterine endothelial proliferation and a decreased Vegf mRNA expression in response to ovarian steroid treatment. Also, although the estrogen receptor alpha (ESR1) expression was lower in subepithelial cells than in controls, a higher expression of silencing mediator of retinoic acid and thyroid hormone receptor (NCOR1, also known as SMRT) corepressor was evidenced in the same compartment. The results indicate that disturbed Vegf expression in BPA rats could be the result of changes in endocrine pathways, such as an altered induction of ESR1 and/or NCOR1 expression. Because of the importance of VEGF in the implantation process, our data suggest that neonatal BPA exposure might have negative consequences on female fertility.
Folliculostellate cells in pituitary pars distalis of male viscacha: immunohistochemical, morphometric and ultrastructural study
Acosta, Mariano; Filippa, Veronica Palmira; Mohamed, Fabian Heber
Folliculostellate ellate cells (FSC) have been reported in pituitary of several mammalian species. FSC morphology and secreted substances have been instrumental to the understanding of their function. The purpose of this work was to perform an immunohistochemical, morphometric and ultrastructural study of the pituitary pars distalis FSC in adult male viscacha and to analyze their relation with hormone secreting cells. Immunohistochemistry and image analysis were carried out in different sectors of the gland, from the middle (sector 1) to the glandular periphery (sector 5). Transmission electron microscopy with lanthanum as electrodense tracer was used. FSC formed follicles with PAS-positive colloid inside. They expressed S-100 protein mainly in both nucleus and cytoplasm. FSC were stellate-like in shape and exhibited short cytoplasmic processes that contacted with blood vessels and endocrine cells. In addition, some follicular colloids were immunostained with anti-S-100 protein. A few FSC were immunostained with anti-glial fibrillary acidic protein (GFAP) and anti-vimentin. The morphometric parameters analyzed (percentages of S-100-positive total, cellular and colloidal areas) increased from sector 1 to sector 3 and then decreased to sector 5. Hormone secreting cells, mainly lactotrophs, gonadotrophs and corticotrophs were associated with FSC and follicles. The ultrastructural study demonstrated that FSC developed junctional complexes and desmosomes between their lateral membranes. Lanthanum freely penetrated the spaces between granulated cells and FSC, but did not penetrate into the follicular lumen. In conclusion: 1) the differential expression of S-100 protein, GFAP and vimentin may indicate different physiological stages of FSC; 2) the expression of these proteins suggests a neuroectodermic origin of these cells; 3) FSC spatial distribution, association with endocrine cells, and the generation of an intercellular communication network suggest that FSC are involved in the pituitary pars distalis paracrine reg ulation of the viscacha.
Changes in floret development patterns that may correlate with sex determination in the PCK clade (Poaceae)
Reinheimer, Renata; Zuloaga, Fernando Omar; Vegetti, Abelardo Carlos; Pozner, Raúl Ernesto
We investigated changes in floral developmental patterns and sex determination in the PCK (phosphoenolpyruvate carboxykinase) clade using a comparative approach and SEM. We identified variation in patterns of floral development that may be correlated with sex determination. Nine different patterns of floret development were identified, based on sex of the lower floret, sequence of stamen development, and rate of glume and lemma differentiation. Although staminate florets are always formed by the abortion of the gynoecium, the timing of abortion differs among species. Similarly, the formation of sterile lower florets showed different pathways that may operate at the level of floral meristem or organ identity. Finally, we discuss several reasons why patterns described for maize and closely related species may not be easily extrapolated to other grasses.
Environmental impact analysis of methanol recovery in biodiesel production using the waste reduction algorithm WAR; Análisis del impacto ambiental de la recuperación de metanol en la producción de biodiesel usando el algoritmo de reducción de desechos WAR
Marticorena, Alfredo A.; Mandagaran, Beatriz Adriana; Campanella, Enrique Angel
The environmental impact of recovering methanol in the traditional process of biodiesel production is presented. Biodiesel represents an alternative for diminishing impact on the environment. However, there are several biodiesel production processes and all of them have different impact on the environment. The methodology consists of simulating the process, apply the WAR algorithm for waste reduction and compare the results. Comparison is also done with literature data for similar cases. The analysis shows that methanol recovery transforms the conventional process of biodiesel production into an environmental friendly process.
Selenium-based self-assembled monolayers: the nature of adsorbate-surface interactions
de la Llave, Ezequiel Pablo; Scherlis Perel, Damian Ariel
In recent years, self-assembled monolayers (SAMs) of selenols have been characterized using electrochemistry, scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), thermal desorption spectroscopy, and other experimental approaches. Interest in the relative stability and conductance of the Se - Au interface as compared to S-Au prompted different investigations which have led to contradictory results. From the theoretical side, on the other hand, the study of selenol-based SAMs has concentrated on the investigation of the electron transport across the Se-Au contact, whereas the structural and the thermodynamic features of the monolayer were essentially neglected. In this Article, we examine the binding of selenols to the Au(111) surface using density functional theory with plane wave basis sets and periodic boundary conditions. Our calculations provide insights on the geometry of the headgroup, the stability of the monolayer, and the electronic properties of the bond. In particular, we propose that the presence of a conjugated backbone might be a major factor determining the relative conductance at the monolayer, by differentially enhancing the intramolecular electron transport in selenols with respect to thiols. This surmise, if confirmed, would explain the conflictive data coming from the available experiments
Electrosynthesis of SER-active silver nanopillar electrode arrays
Feng, Jiu-Ju; Lu, Ya-Hui; Gernet, U.; Hildebrandt, Peter; Murgida, Daniel Horacio
Here we report a one step electrochemical method for the deposition of pillar-like silver nanostructures on graphite plate electrodes. The devices were tested as SER-active electrode arrays using covalently attached hemin. The nanopillar arrays provide reproducible surface enhanced resonance Raman (SERR) signals within 6% standard deviation and Raman enhancement factors of 1 × 105. They also show good electrochemical performance, as verified by potential-dependent SERR spectroscopy and cyclic voltammetry. Furthermore, the hemin-coated arrays display mediatorless electrocatalytic activity toward NO2-. Thus, the Ag nanopillar arrays present good prospects for their application in sensing devices and for SER/SERR based spectroelectrochemical applications in general.
La revista Católica Criterio y la defensa del hispanismo durante el segundo gobierno de Juan D. Perón (Argentina, 1952-1955); The Catholic journal Criterio and the defense of hispanism during the second government of Juan D. Peron (Argentina, 1952-1955)
Glozman, Mara Ruth
El segundo gobierno del presidente argentino Juan D. Perón (1952-1955) fue un período de fuertes confrontaciones entre sectores que impulsaban diferentes proyectos político-culturales. Uno de los aspectos polémicos del proyecto gubernamental fue la reivindicación del derecho del Estado nacional argentino para la producción de instrumentos lingüísticos propios, discurso que generó reacciones de rechazo de diferentes sectores sociales y políticos. En aquel contexto, la revista católica Criterio publicó una serie de notas y artículos de opinión en los cuales se expresaba una abierta defensa del legado hispánico y de la autoridad académica en materia idiomática. Este artículo se propone analizar el sistema de representaciones en el que se sustentaba la posición glotopolítica de la revista Criterio, articulando el estudio histórico de las ideologías lingüísticas con el análisis de las principales operaciones discursivo-argumentativas que se despliegan en los textos del corpus.
Detection and characterization of N-glycolyated gangliosides in Wilms tumor by immunohistochemistry
Scursoni, Alejandra M.; Galluzzo, Laura; Camarero, Sandra; Pozzo, Norma; Gabri, Mariano Rolando; De Acosta, Cristina Mateo; Vázquez, Ana María; Alonso, Daniel Fernando; De Davila, María Teresa G.
Gangliosides are glycolipids present on the cell surface. The N-glycolylated ganglioside NeuGc-GM3 has been described in some neoplasms, such as breast carcinoma and melanoma, but is usually not detected in normal human cells. Our aim was to evaluate the presence of NeuGc-GM3 in Wilms tumor by immunohistochemistry. Postchemotherapy tumors were grouped into different histologic subtypes considering the main preserved component. Formalin-fixed, paraffin-embedded tumor samples were cut into 5-mm sections. The monoclonal antibody 14F7, a mouse IgG1 that specifically recognizes NeuGc-GM3, and a peroxidase-labeled polymer conjugated to secondary antibodies were used. Sections from breast carcinoma were employed as positive controls. Presence of NeuGc-GM3 was evident in 22 of 25 (88%) cases. The staining was stronger in the epithelial component, with a membrane pattern and cytoplasmic diffusion. The stromal component expressed cytoplasmic NeuGc-GM3 in cells with rhabdomyoblastic differentiation. Tubules of adjacent renal tissue were also positive, but no expression of NeuGc-GM3 was detected in nontumoral fetal kidney. Until now, the expression of N-glycolylated gangliosides in pediatric solid tumors has not been investigated. The present study evidenced the expression of NeuGc-GM3 in a high proportion of Wilms tumors, suggesting its potential utility as a specific target of immunotherapy.
Diversity of trichomycetes in larval flies from aquatic habitats in Argentina
Siri, Augusto; Lopez Lastra, Claudia Cristina
Trichomycetes, mainly from nonbiting midge (Chironomidae), mosquito (Culicidae) and black fly (Simuliidae) larvae (Insecta: Diptera), are reported from diverse freshwater environments principally from previously unexplored areas of Argentina. Four new species of Harpellales are described: Austrosmittium patagonicum, A. lenticum, Smittium basiramosum and Legeriomyces lichtwardtii. This is the first report of Austrosmittium spp. from the Americas and the first report of a Legeriomyces from South America. Two other species (Simuliomyces sp. and Harpella sp.) are described but not named. Fourteen previously described species were recovered, and their geographical distribution and host ranges have been extended for Argentina, with Sm. phytotelmatum, Stachylina lentica, St. lotica and St. penetralis being new records for the country.
Needs Assessment for Climate Information on Decadal Timescales and Longer
Vera, Carolina Susana; Barange, M.; Dube, O. P.; Goddard, L.; Griggs, D.; Kobysheva, N.; Odada, E.; Parey, S.; Polovina, J.; Poveda, G.; Seguin, B.; Trenberth, K.
Societal needs for climate information on decadal timescales is confirmed in terms of its potential value and relevance as a driver in sector decision-making, but such information is currently lacking. Predictions and observationally based analyses for decadal climate variability and change are needed. In addition, the following issues have been identified as those that must be addressed in order to facilitate effective use of climate information on decadal timescales in the decision-making processes of different socio-economic sectors: building effective partnership systems linking stakeholders, users and decision-making sectors and climate information providers; more research and investment is to translate information of large-scale decadal variations into the regional and local scales required for decisions; maintaining and sustaining the Global Climate Observing System (GCOS), in particular, enhancement of the global ocean observing system; and, ways to assemble, check quality, reprocess and reanalyse datasets relevant to decadal prediction. Ways of securing climate observing systems particularly in least developed regions are urgently needed.
