Late Cambrian acritarchs from the Santa Rosita Formation: implications for the Cambrian-Ordovician boundary in the eastern Cordillera of northwest Argentina

Marine phytoplankton from the Late Cambrian are described for the first time in the Eastern Cordillera of northwest Argentina. The acritarch assemblage was recovered from an offshore lower mudstone unit towards the base of the Casa Colorada Member (Santa Rosita Formation) in the Quebrada de Moya section, Jujuy Province. The presence of Vulcanisphaera africana, Saharidia fragilis, Granomarginata squamacea and Celtiberium sp. 1, together with the absence of Tremadocian acritarch species and the scarcity and low diversity of diacrodian acritarchs suggest an age not younger than Late Cambrian for this acritarch assemblage. This ageassignment is also supported by stratigraphic information and regional correlations.Fil: Rubinstein, Claudia Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Mangano, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Buatois, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; Argentin

Normal spatial learning and improved spatial working memory in mice (mus musculus) lacking dopamine d4 receptors

Dopamine terminals in the hippocampus and prefrontal cortex modulate cognitive processes such as spatial learning and working memory. Because dopamine D4 receptors are expressed in these brain areas we have analyzed mutant mice lacking this receptor subtype (Drd4-/-). Wild-type and Drd4-/- mice were challenged in two spatial learning paradigms: the Morris water maze and an alternation T-maze. Drd4-/- mice showed normal place learning ability to find a hidden platform based on spatial extra-maze cues. In addition, Drd4-/- mice were able to find a new platform location with the same learning plasticity as wild type-mice. Spatial working memory assessed on a T maze showed that Drd4-/- mice were more efficient than wild-type mice in acquiring the maximum plateau of correct alternation scores. These results provide further evidence that the functional consequence of lacking D4 receptors is more evident in behaviors dependent on the integrity of the prefrontal cortex.Fil: Falzone, Tomas Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Avale, Maria Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Gelman, Diego Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Rubinstein, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentin

Regulated expression of galectin-1 after in vitro productive infection with herpes simplex virus type 1: implications for T cell apoptosis

Apoptosis of cytotoxic T lymphocytes by herpes simplex virus type-1 (HSV-1) has been reported to be a relevant mechanism of viral immune evasion. Galectin-1 (Gal-1), an endogenous lectin involved in T-cell apoptosis, has recently gained considerable attention as a novel mechanism of tumor-immune evasion. Here we investigated whether infection of cells with HSV-1 can modulate the expression of Gal-1. Results show that pro-apoptotic Gal-1, but not Gal-3, is remarkably up-regulated in cell cultures infected with HSV-1. In addition, this protein is secreted to the extracellular milieu, where it contributes to apoptosis of activated T cells in a carbohydrate-dependent manner. Since many viruses have evolved mechanisms to counteract the antiviral response raised by the infected host, our results suggest that HSV-1 may use galectin-1 as a weapon to kill activated T cells and evade specific immune responses.Fil: Gonzalez, Maria Ines. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología; ArgentinaFil: Rubinstein, Natalia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ilarregui, Juan Martin. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Toscano, Marta Alicia. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Sanjuan, Norberto Aníbal. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología; ArgentinaFil: Rabinovich, Gabriel Adrián. Universidad de Buenos Aires. Facultad de Medicina. Departamento de Microbiología; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin

Revisiting reverse osmosis as a mechanism contributing to metal zoning in porphyry copper deposits

The Mid Permian San Pedro porphyry deposit in the San Rafael Massif (central-western Argentina) offers a valuable opportunity to contribute in the understanding of ore concentration mechanisms operating during the phyllic alteration stage. In this deposit, two generations of low-temperature D-veins (D1 and D2) formed during the phyllic alteration stage. The D2-type veins show an atypical Cu-Ag sulfide paragenesis consisting mainly of galena, chalcocite, native silver, chalcopyrite and bornite, which can not be explained using the traditional cooling model. Based on previous research and own data, we test Reverse Osmosis as a possible mechanism contributing to D2-vein ore deposition. Reverse Osmosis is a pressure-driven retention-selective membrane filtration process resulting in solute/ion retention on the high-pressure side of the membrane. D2-veins from San Pedro porphyry formed at 211°–176 °C during transient fluid overpressures produced by the hydrothermal sealing that followed the earlier D1-vein formation. Besides the temperature range and the declining orogeny, physico-chemical conditions were optimal for Reverse Osmosis to activate because the presence of a semi-permeable phyllic membrane and a transmembrane pressure gradient with hydrothermal fluid pressure exceeding the relatively low stress normal to the fracture walls (σn). This particular condition activated Reverse Osmosis, allowing to get similar membrane rejection values for Cu and Ag chloride complexes at lower fluid temperatures, causing the decrease of the osmotic differentiation performance, and the consequent coeval precipitation of Cu and Ag sulfide minerals.Fil: Japas, Maria Silvia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Rubinstein, Nora Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Gómez, Anabel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; Argentin

Dopaminergic innervation at the central nucleus of the amygdala reveals distinct topographically segregated regions

The central nucleus of the amygdala (CeA) is involved in the expression of fear and anxiety disorders. Anatomically, it is divided into medial (CeM), lateral (CeL), and capsular (CeC) divisions. The CeA is densely innervated by dopaminergic projections that originate in the ventral periaqueductal gray/dorsal raphe (vPAG/DR) and the ventral tegmental area (VTA). However, whether dopamine (DA) exerts a homogenous control over the CeA or differentially regulates the various CeA subdivisions is still unknown. Here, we performed a neuroanatomical analysis of the mouse CeA and found that DAergic innervations from the PAG/DR and VTA constitute distinct, non-overlapping, pathways differing also in the relative expression of the dopamine transporter. By quantifying the distribution of DAergic fibers and the origin of DA inputs we identified two distinct regions in the CeL: a frontal region innervated by the VTA and vPAG/DR, a caudal region innervated only by the vPAG/DR, and three distinct regions in the CeC: fronto-dorsal innervated only by the VTA, fronto-ventral with sparse DAergic innervation, and a caudal region with low innervation from the vPAG/DR. In addition, we found that each region displays a distinct pattern of c-Fos activation following the administration of various DAeric drugs such as cocaine, SKF 38,393, quinpirole or haloperidol. In summary, we revealed unique properties of the DAergic pathways innervating the CeA, distinguishing six topographically segregated and functionally distinct regions. This unanticipated level of heterogeneity calls for more precise neuroanatomical specificity in future functional studies of the CeA.Fil: Casey, Eric. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Avale, Maria Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Kravitz, Alexxai. Washington University in St. Louis; Estados UnidosFil: Rubinstein, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentin

Characteristics of Central II alteration zone, San Rafael Massif, province of Mendoza

Se presenta el estudio petrográfico de las muestras de superficie correspondientes a la zona de alteración Central II, localizada en el Bloque San Rafael, provincia de Mendoza (34°54'56" S; 68°37'02" O). La misma está relacionada a la intrusión de un cuerpo hipabisal de composición riolítica alojado en una sucesión de rocas volcánicas y volcaniclásticas de la sección superior del Grupo Choiyoi. La zona de alteración está representada por sericitización generalizada a la que se sobreimponen brechas y venas silíceas, ocasionalmente con textura drusiforme y con bandas tapizadas por agregados diseminados de pirita y calcopirita subordinada, a las que acompaña escasa arsenopirita. Las brechas y venas silíceas conforman una faja de dirección ONO (azimut 290° - 300°) e inclinación vertical, en las que se han reconocido texturas de cuarzo hidrotermal de crecimiento primario, de recristalización y de reemplazo. Entre estas texturas se destacan las crustificaciones complejas, el bandeamiento coloforme y los pseudomorfos de cuarzo según calcita en enrejado, a las que se asocia la presencia de adularia con morfologías sub-rómbica, rómbica y pseudo-acicular. Este conjunto de texturas y morfologías permite establecer que se trata de un sistema epitermal de baja sulfuración con paleozonas de ebullición ascendente.The goal of this paper is to present the petrographic study from outcrop samples of the Central II alteration zone. This area is located in the San Rafael Massif, province of Mendoza (34°54'56" S; 68°37'02" O) and is related to hypoabyssal rhyolitic bodies that intrude a volcanic-volcaniclastic sequence corresponding to the upper section of Choiyoi Group. The alteration zone is represented by pervasive sericitization overprinted by silicic breccias and veins with WNW trend (Az 290° - 300°) and vertical dip. Hydrothermal veins are mainly composed by quartz with primary growth, recrystalization and replacement textures with minor pyrite, chalcopyrite and scarce arsenopyrite. The combination of crustifiform - colloform silica banding, quartz pseudomorphs of bladed calcite and adularia with different morphologies (sub-rhombic, rhombic and pseudo-acicular) is a clear evidence of a low-sulfidation epithermal system with paleozones of upflow boiling.Fil: Gargiulo, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Geológico del Sur. Universidad Nacional del Sur. Departamento de Geología. Instituto Geológico del Sur; ArgentinaFil: Rubinstein, Nora Alicia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Geología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Geociencias Básicas, Aplicadas y Ambientales de Buenos Aires; ArgentinaFil: Carpio, Francisco. Secretaría de Industria y Minería. Servicio Geológico Minero Argentino; ArgentinaFil: Salvarredi, Julio.. Comisión Nacional de Energía Atómica; Argentin

Eliminating artificial trans fatty acids in Argentina: estimated effects on the burden of coronary heart disease and costs

Objective: To estimate the impact of Argentine policies to reduce trans fatty acids (TFA) on coronary heart disease (CHD), disability-adjusted life years (DALYs) and associated health-care costs. Methods: We estimated the baseline intake of TFA before 2004 to be 1.5% of total energy intake. We built a policy model including baseline intake of TFA, the oils and fats used to replace artificial TFAs, the clinical effect of reducing artificial TFAs and the costs and DALYs saved due to averted CHD events. To calculate the percentage of reduction of CHD, we calculated CHD risks on a population-based sample before and after implementation. The effect of the policies was modelled in three ways, based on projected changes: (i) in plasma lipid profiles; (ii) in lipid and inflammatory biomarkers; and (iii) the results of prospective cohort studies. We also estimated the present economic value of DALYs and associated health-care costs of coronary heart disease averted. Findings: We estimated that projected changes in lipid profile would avert 301 deaths, 1066 acute CHD events, 5237 DALYs and 17 million United States dollars (US$) in health-care costs annually. Based on the adverse effects of TFA intake reported in prospective cohort studies, 1517 deaths, 5373 acute CHD events, 26 394 DALYs and US$ 87 million would be averted annually. Conclusion: Even under the most conservative scenario, reduction of TFA intake had a substantial effect on public health. These findings will help inform decision-makers in Argentina and other countries on the potential public health and economic impact of this policy.Fil: Rubinstein, Adolfo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Elorriaga, Natalia. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Garay, Ulises. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Poggio, Rosana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Caporale, Joaquin. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Matta, Maria Gabriela. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Augustovski, Federico Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Pichón-Riviere, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto de Efectividad Clínica y Sanitaria; ArgentinaFil: Mozaffarian, Dariush. Tufts University; Estados Unido

C/EBP-β Regulates Endoplasmic Reticulum Stress–Triggered Cell Death in Mouse and Human Models

Endoplasmic reticulum (ER) stress elicits the unfolded protein response (UPR), initially aimed at coping with the stress, but triggering cell death upon further stress. ER stress induces the C/EBP-® variant Liver-enriched Activating Protein (LAP), followed by the dominant-negative variant, Liver Inhibitory Protein (LIP). However, the distinct role of LAP and LIP in ER stress is unknown. We found that the kinetics of the ER stress-induced expression of LIP overlapped with that of the cell death in mouse B16 melanoma cells. Furthermore, inducible over-expression of LIP augmented ER stress-triggered cell death whereas over-expression of LAP attenuated cell death. Similar results were obtained in human 293T cells. Limited vasculature in tumors triggers hypoxia, nutrient shortage and accumulation of toxic metabolites, all of which eliciting continuous ER stress. We found that LAP promoted and LIP inhibited B16 melanoma tumor progression without affecting angiogenesis or accelerating the cell cycle. Rather, LAP attenuated, whereas LIP augmented tumor ER stress. We therefore suggest that C/EBP-® regulates the transition from the protective to the death–promoting phase of the UPR. We further suggest that the over-expression of LAP observed in many solid tumors promotes tumor progression by attenuating ER stress–triggered tumor cell death

Selective disruption of dopamine D2 receptors in pituitary lactotropes increases body weight and adiposity in female mice

Prolactin, a pleiotropic hormone secreted by lactotropes, has reproductive and metabolic functions. Chronically elevated prolactin levels increase food intake, but in some hyperprolactinemic states such as in the global dopamine D2 receptor (D2R) knockout mouse, food intake is not increased. Here, we conduct a cell-specific genetic dissection study using conditional mutant mice that selectively lack D2Rs from pituitary lactotropes (lacDrd2KO) to evaluate the role of elevated prolactin levels without any confounding effect of central D2Rs on motor and reward mechanisms related to food intake. LacDrd2KO female mice exhibited chronic hyperprolactinemia, pituitary hyperplasia, and a preserved GH axis. In addition, lacDrd2KO female but not male mice evidenced increased food intake by three months of age and, from five months onwards their body weights were heavier. A marked increment in fat depots, adipocyte size, serum triglyceride and non-esterified fatty acid levels, and a decrease in lipolytic enzymes in adipose tissue were evidenced. Furthermore, lacDrd2KO female mice had glucose intolerance but a preserved response to insulin. In the hypothalamus Npy mRNA expression was increased, and Pomc and Ppo mRNA levels were unaltered (in contrast to results in global D2R knockout mouse). Thus, the orexigenic effect of prolactin, and its action on hypothalamic Npy expression were fully evidenced, leading to increased food intake and adiposity. Our results highlight the metabolic role of prolactin and illustrate the value of studying cell-specific mutant mice to disentangle patho-physiological mechanisms otherwise masked in null allele mutants or in animals treated with pervasive pharmacological agents.Fil: Pérez Millán, María Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Luque, Guillermina Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Ramirez, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Noain, Daniela Maria Clara. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular; ArgentinaFil: Ornstein, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Rubinstein, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular; ArgentinaFil: Becu, Damasia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin

Avaliação da influência do polimento químico na sorpção, solubilidade e microdureza de uma resina acrílica de termopolimerização

A proposta desse trabalho foi avaliar a influência do polimento químico, quando comparado ao polimento mecânico, nas propriedades de sorpção, solubilidade e microdureza de uma resina acrílica termopolimerizável. Os ensaios foram realizados utìizando-se a resina acrílica de termopolimerização da marca Clássico (Art. Odontológicos Clássico Ltda.,S.P.). A sorpção e solubilidade foram realizadas conforme a especificação nº1567 da International Organization for Standartization (ISO), confeccionando-se 20 corpos de prova no formato de discos, divididos aleatoriamente em dois grupos, onde o primeiro recebeu o polimento mecânico com pastas abrasivas, e o segundo, o polimento químico durante 10s, na polidora química PQ 9000 (série 4868-2, Termotron do Brasil Ltda., Piracicaba, SP). Os corpos de prova foram mantidos em um dissecador com sílica gel, a 37ºC, até que apresentassem massa constante (MI), obtida numa balança com resolução de 0,0001g. As amostras foram imersas em água destilada a 37ºC, durante 7 dias, e novamente pesadas (M2). A diferença ente M2 e Ml em relação ao volume de cada corpo de prova resultou na sorpção. A seguir, os corpos de prova foram novamente dissecados até a obtenção de massa constante (M3). A diferença entre Ml e M3 em relação ao volume de cada corpo de prova resultou na solubilidade dos mesmos. Para a execução do ensaio de microdureza Knoop foram confeccionados 20 corpos de prova de resina acrílica, dos quais 10 amostras receberam o polimento mecânico e as demais, o polimento químico. A mensuração da microdureza foi realizada no NU Research Microscope (VEB Carl Zeiss JENA- Germany). Os resultados indicaram que a técnica de polimento químico é aceitável quando considerada a propriedade de sorpção, porém inviável quanto à propriedade de solubilidade, de acordo com a especificação nºI567 da ISO. O polimento químico também reduziu significativamente a dureza superficial da resina acrílica, cujas consequências poderão interferir no desempenho clínico do material