Genetic variation in resistance to leaf fungus indirectly affects spider density Slinn, Heather; Barbour, Matthew A.; Crawford, Kerri; Rodriguez Cabal, Mariano Alberto; Crutsinger, Gregory M. Many host-plants exhibit genetic variation in resistance to pathogens; however, little is known about the extent to which genetic variation in pathogen resistance influences other members of the host-plant community, especially arthropods at higher trophic levels. We addressed this knowledge gap by using a common garden experiment to examine whether genotypes of Populus trichocarpa varied in resistance to a leaf-blistering pathogen, Taphrina sp., and in the density of web-building spiders, the dominant group of predatory arthropods. In addition, we examined whether variation in spider density was explained by variation in the density and size of leaf blisters caused by Taphrina. We found that P. trichocarpa genotypes exhibited strong differences in their resistance to Taphrina and that P. trichocarpa genotypes that were more susceptible to Taphrina supported more web-building spiders, the dominant group of predatory arthropods. We suspect that this result is caused by blisters increasing the availability of suitable habitat for predators, and not due to variation in herbivores because including herbivore density as a covariate did not affect our models. Our study highlights a novel pathway by which genetic variation in pathogen resistance may affect higher trophic levels in arthropod communities.

Quantitative geomorphology applied to fluvial dynamic in Aviles and Moneta basins, Tierra Del Fuego, Southern Argentina Quiroga, Diego Rubén Andrés; Gil, Veronica; Coronato, Andrea Maria Josefa The morphometric characteristics of the Moneta river basin are compared to those of the Avilés river basin. Both are located in the north of the province of Tierra del Fuego in Argentina, and they also have their catchment area in the same range: the Sierras del Bosque; runoff on the NE-oriented slopes forms the Avilés river basin, while runoff on the SE slopes forms the Moneta river basin. The analysis was made in two different scales: the first as a general scale of the basin, and the second as the catchment sector (upper, middle and lower). The quantitative analysis was applied in order to know the behavior of these two fluvial systems. For the analysis, a cartographic basis scale to 1: 20,000 was used, which was made on a mosaic of images from Google Earth®; the altimetric information was obtained throughout a digital elevation model of 45-m spatial resolution SRTM45 (Shuttle Radar Topographic Mission). The indices used were Rr, Rb, Ish and Dd to characterize the geological and geomorphological context, and Rl, Re, If, Ct and Ca to infer the behavior of the runoff in the catchment. It was established that the Moneta river basin reaches 6 in order of hierarchy; its main channel is 65.52 km long. The Re determines an elongated basin. The Ct obtained in the basin is 0.96, whereas the sub-basin level was identified to a maximum value of the O3-SM-10 (1.46). The Dd is low (1.94 km/km2), which is directly proportional to the intensity of rainfall and the slopes of the area considered. The comparison, made at the same scale, between basins determines specific fluvial characteristics of each sector (upper, middle and lower).

Identidad, verdad, responsabilidad: configuraciones discursivas de las y los nietos restituidos en la escena pública; Identity, truth, responsibility: discursive constructions of the restituted grandchildren in the public scene Quintana, María Marta En 2007, a propósito de su trigésimo aniversario, Abuelas de Plaza de Mayo publica La historia de Abuelas. 30 años de búsqueda. Se trata de un libro en el que la Asociación se presenta como un organismo socialmente legitimado, en un contexto político favorable a la causa de los derechos humanos, y en el que se traen a escena las voces de los propios nietosrestituidos. Puesson ellos quienes afirman el carácter liberador de la restitución y argumentan que la verdad, aunque conlleve dolor, siempre es preferible a la mentira, el robo, el ocultamiento. En este sentido, la publicación funciona como un marco global para las historias de los jóvenes encontrados, y es mediante esa configuración enunciativa que se produce un discurso coherente entre las afirmaciones de las Abuelas y las de los nietos. En virtud de ello, en este trabajo se examinan las configuraciones discursivas (seleccionadas y exhibidas por La Historia de Abuelas…) de las y los jóvenes restituidos. En primer lugar se problematizan las apelaciones esencialistas a ‘la sangre’, para luego avanzar en un análisis del proceso de desvelamiento de la verdad y las implicancias éticas de la restitución de identidad.; In 2007, with regard to its thirtieth anniversary, Abuelas de Plaza de Mayo publishes La historia de Abuelas. 30 años de búsqueda. This is a book in which the Association presents itself as a socially legitimated organization in a favorable political context regarding the cause of human rights, and in which the voices of grandchildren are brought on stage. It is them, who affirm the liberating character of restitution and argue that truth, even if it entails pain, it is always preferable to lies, theft and concealment. In this regard, the publication serves as a comprehensive framework for the stories of young people found, and it is through this declarative configuration that a coherent discourse between the statements of the Grandmothers and the grandchildren occurs. Against this, this paper examines the discursive configurations (selected and displayed by La historia de Abuelas...) of the returned young people. First, I problematize essentialist appeals to ‘blood’, turning afterwards to the analysis of the process of truth unveiling and finally to the ethical implications of identity restitution.

Retrieval of the optical properties of a semiinfinite compartment in a layered scattering medium by single-distance, time-resolved diffuse reflectance measurements García, Héctor Alfredo; Iriarte, Daniela Ines; Pomarico, Juan Antonio; Grosenick, D.; Macdonald, R. Functional analysis of the human brain requires methods that take the layered structure of the head into account. In this work we introduce an improved theoretical model that describes light propagation in multilayered, turbid cylinders with a infinitely thick bottom layer, which simplifies calculations and reduces computation times. Our approach was validated with Monte Carlo simulations and single distance, time-resolved experiments on a three-layered phantom, where the absorption of the deepest layer was gradually modified. We were able to retrieve both, the scattering and absorption coefficient of this layer within reasonable errors. Hereby, changes in scattering were found to have less effect on the experimental data than absorption changes, making the reliable estimation of the reduced scattering coefficient more difficult in comparison to absorption. Stability of the implemented fitting routine was thoroughly analyzed, revealing that special care is needed to obtain accurate values for the reduced scattering coefficient.

A microstructural study of acrylic-modified chitosan by means of PALS and SAXS Anbinder, Pablo Sebastián; Macchi, Carlos Eugenio; Amalvy, Javier; Somoza, Alberto Horacio Chemical modification of chitosan, specially grafting with different polymers is an important strategy in the production of bio-based materials with enhanced properties. In the present study, chitosan was grafted with n-butyl acrylate, in a surfactant-free emulsion polymerization. Stable dispersions with high grafting efficiency were obtained and the microstructure of the casted films was analyzed by positron annihilation lifetime spectroscopy and small angle X-ray scattering. Results are discussed in terms of the number and distribution of the grafting sites.

Solvatomorphs of 25,26,27,28-tetrahydroxycalix[4]arene and 5,11,17,23-tetramino-25,26,27,28-tetrabutoxycalix[4]arene: quenching photoluminescence through switching the guest Martins, Felipe Terra; Maia, Lauro June Queiroz; Da Silva Neto, Leonardo; Da Silva, Cleiton Moreira; Sarotti, Ariel Marcelo; De Fátima, Ângelo Here, we have disclosed two solid state forms of 5,11,17,23-tetramino-25,26,27,28-tetrabutoxycalix[4]arene (1) and two solid state forms of the non-functionalized 25,26,27,28-tetrahydroxycalix[4]arene (2). This is the first structural knowledge of a tetra-amino functionalized calixarene derivative, even though this compound is well known and used as a precursor of several other functionalized calix[4]arenes. The two solid forms of 1 differ by the presence of either water or water/dimethylsulfoxide (DMSO) solvent molecules entrapped in the major calixarene cavity, even though the pinched conformation is adopted in both forms as a consequence of the contacts between solvent molecules and phenyl rings. Likewise, the switch from water to DMSO in the cone cavity of 1 has abrogated the photoluminescence (PL) found only in the dihydrate form. Frontier molecular orbital calculations at the B3LYP/6-31G* level of theory support a short-range electron transfer between guest (DMSO) and host (1) molecules quenching the solid state photoluminescence when DMSO is entrapped in the cone. This solvatomorphism approach for PL search in calixarenes opens a perspective on tuning and even increasing the performance of calixarenes through changing the guest solvent molecule. Similarly, the two crystal forms of 2 entrap either methyl alcohol or DMSO in their cones, which, as well as both crystal forms of 1, are packed into sheets through different fashions and contact patterns.

Delving into the Secular Stagnation Hypothesis: A Firm-Level Analysis of the Private Sector's Excess Savings in Advanced Economies Perez Artica, Rodrigo; Brufman, Leandro; Martinez, Lisana Belén We document a persistent increase in excess savings (defined as the difference between gross savings and capital formation) and a steady decline of gross capital formation in a sample of non-financial firms from developed countries. These patterns developed even before the financial breakdown of 2007 reinforcing the case for a secular stagnation hypothesis. They go along with a deleveraging process and a decrease in the share of operating assets in total assets. We discuss three possible explanations for this long-term behavior: financial constraints, operative volatility, and the weakening of business dynamism itself.

Increased dietary levels of α-linoleic acid inhibit mammary tumor growth and metastasis Vara Messler, Marianela; Pasqualini, María Eugenia; Comba, Andrea; Silva, Renata Alejandra; Buccellati, Carola; Trenti, Annalisa; Trevisi, Lucia; Eynard, Aldo Renato; Sala, Angelo; Bolego, Chiara; Valentich, Mirta Ana The aim of this study was to determine whether α-linolenic acid (ALA ω-3 fatty acid) enriched diet affects growth parameters when applied to a syngeneic model of mammary carcinoma. Materials and methods: BALB/c mice were divided and fed with: 1) a chia oil diet, rich in ALA or 2) a corn oil diet, rich in linoleic acid (LA ω-6 fatty acid). Mice were subcutaneously inoculated with a tumor cell line LM3, derived from a murine mammary adenocarcinoma. Results: After 35 days, tumor incidence, weight, volume and metastasis number were lower in the ALA-fed mice, while tumor latency time was higher, and the release of pro-tumor metabolites derived from ω-6 fatty acids decreased in the tumor. Compared to the control group, a lower number of mitosis, a higher number of apoptotic bodies and higher T-lymphocyte infiltration were consistently observed in the ALA group. An ALA-rich diet decreased the estrogen receptor (ER) α expression, a recognized breast cancer promotor while showing an opposite effect on ERβ in tumor lysates. Conclusion: These data support the anticancer effect of an ALA-enriched diet, which might be used as a dietary strategy in breast cancer prevention.

Measurement of expansin activity and plant cell wall creep by using a commercial texture analyzer Perini, Mauro Alejandro; Sin, Ignacio Nicolás; Martinez, Gustavo Adolfo; Civello, Pedro Marcos Background Expansins play an important role in cell wall metabolism and fruit softening. Determination of expansin activity is a challenging problem since it depends on measuring cell wall properties by using ad hoc extensometers, a fact that has strongly restricted its study. Then, the objective of the work was to adapt a methodology to measure cell wall creep and expansin activity using a commercial texture meter, equipped with miniature tensile grips and an ad hoc cuvette of easy construction. Results It was possible to measure hypocotyls acid growth and expansin activity in a reliable and reproducible way, using a commercial texture meter, common equipment found in laboratories of food science or postharvest technology. Expansin activity was detected in protein extracts from cucumber hypocotyls, tomato and strawberry fruits, and statistical differences in expansin activity were found in both fruit models at different ripening stages. Conclusions The possibility of measuring expansin activity following this adapted protocol with a commercial texture meter could contribute to ease and increase the analysis of expansin in different systems, leading to a better understanding of the properties of these proteins under different experimental conditions.

A new species in the troglomorphic scorpion genus Troglotayosicus from Colombia, representing the northernmost known record for the genus (Scorpiones, Troglotayosicidae) Botero Trujillo, Ricardo; González Gómez, Julio C.; Valenzuela Rojas, Juan C.; García, Luis F. We describe a new scorpion species in the troglomorphic genus Troglotayosicus Lourenço, 1981 from Colombia. Troglotayosicus meijdeni sp. nov. inhabits the forest leaf litter at Rivera municipality, on the western slope of the Eastern Andes. The male of the new species remains unknown; however, this species can be distinguished from other species in the genus by the female (and juvenile) morphology. The type locality of T. meijdeni sp. nov. represents the northernmost known record for a population of Troglotayosicus, further extending the known limits of distribution of this genus, and shedding more light on the distributional range of this group of scorpions in northwestern South America. With this description, the number of known species of Troglotayosicus is raised to four; three of them are endogean species living in forested areas in the Andean region of Colombia, whereas one is a hypogean species from a cave in Ecuadorian Amazonia.

New evidence for the therapeutic potential of curcumin to treat nonalcoholic fatty liver disease in humans Inzaugarat, Maria Eugenia; de Matteo, Elena Noemí; Baz, Placida; Lucero, Diego Martín; García, Cecilia Claudia; Gonzalez Ballerga, Esteban; Daruich, Jorge; Sorda, Juan Antonio; Wald, Miriam Ruth; Cherñavsky, Alejandra Claudia Introduction: The immune system acts on different metabolic tissues that are implicated in the pathogenesis of nonalcoholic fatty liver disease (NAFLD). Leptin and linoleic acid have the ability to potentially affect immune cells, whereas curcumin is a known natural polyphenol with antioxidant and anti-inflammatory properties. Aims: This study was designed to evaluate the pro-inflammatory and pro-oxidant effects of leptin and linoleic acid on immune cells from patients with NAFLD and to corroborate the modulatory effects of curcumin and its preventive properties against the progression of NAFLD using a high-fat diet (HFD)-induced NAFLD/nonalcoholic steatohepatitis mouse model. Results: The ex vivo experiments showed that linoleic acid increased the production of reactive oxygen species in monocytes and liver macrophages, whereas leptin enhanced tumor necrosis factor-α (TNF-α) production in monocytes and interferon-γ production in circulating CD4+ cells. Conversely, oral administration of curcumin prevented HFD-induced liver injury, metabolic alterations, intrahepatic CD4+ cell accumulation and the linoleic acid- and leptin- induced pro-inflammatory and pro-oxidant effects on mouse liver macrophages. Conclusion: Our findings provide new evidence for the therapeutic potential of curcumin to treat human NAFLD. However, the development of a preventive treatment targeting human circulating monocytes and liver macrophages as well as peripheral and hepatic CD4+ cells requires additional research.

Iodide handling disorders (NIS, TPO, TG, IYD) Targovnik, Hector Manuel; Citterio, Cintia Eliana; Rivolta, Carina Marcela Iodide Handling Disorders lead to defects of the biosynthesis of thyroid hormones (thyroid dyshormonogenesis, TD) and thereafter congenital hypothyroidism (CH), the most common endocrine disease characterized by low levels of circulating thyroid hormones. The prevalence of CH is 1 in 2000–3000 live births. Prevention of CH is based on prenatal diagnosis, carrier identification, and genetic counseling. In neonates a complete diagnosis of TD should include clinical examination, biochemical thyroid tests, thyroid ultrasound, radioiodine or technetium scintigraphy and perchlorate discharge test (PDT). Biosynthesis of thyroid hormones requires the presence of iodide, thyroid peroxidase (TPO), a supply of hydrogen peroxide (DUOX system), an iodine acceptor protein, thyroglobulin (TG), and the rescue and recycling of iodide by the action of iodotyrosine deiodinase or iodotyrosine dehalogenase 1 (IYD or DEHAL1). The iodide transport is a two-step process involving transporters located either in the basolateral or apical membranes, sodium iodide symporter (NIS) and pendrin (PDS), respectively. TD has been linked to mutations in the solute carrier family 5, member 5 transporter (SLC5A5, encoding NIS), solute carrier family 26, member 4 transporter (SLC26A4, encoding PDS), TPO, DUOX2, DUOXA2, TG and IYD genes. These mutations produce a heterogeneous spectrum of CH, with an autosomal recessive inheritance. Thereafter, the patients are usually homozygous or compound heterozygous for the gene mutations and the parents, carriers of one mutation. In the last two decades, considerable progress has been made in identifying the genetic and molecular causes of TD. Recent advances in DNA sequencing technology allow the massive screening and facilitate the studies of phenotype variability. In this article we included the most recent data related to disorders caused by mutations in NIS, TPO, TG and IYD.

Presencia del Inca en Yocavil (Catamarca, Argentina). Integración en la diversidad; Inca presence in Yocavil (Catamarca, Argentina). Integration in diversity Tarrago, Myriam Noemi; Marchegiani, Marina Ines; Palamarczuk, Valeria; Reynoso, Alejandra Daniela Se ofrece una síntesis sobre las particularidades de la pre sencia incaica en el sur de Yocavil (Catamarca, Argentina), ponderando las características de las instalaciones imperiales, la alfarería incaica que circuló en la región y la relevancia del Qhapaq Ñan como eje integrador. Esta síntesis integra nueva información sobre instalaciones relevantes como El Calvario de Fuerte Quemado y Punta de Balasto. Se reflexiona sobre las características de las interacciones entre las sociedades locales y el Estado incaico en expansión, privilegiando el estudio de los procesos de cambio a partir de la posición de las sociedades dominadas.; This is a synthesis on the main features of the Inca presence in area of southern Yocavil (Catamarca, Argentina), that considers imperial settings, Inca pottery that circulated in the region and the relevance of Qhapaq Ñan as an integrating axis. This synthesis includes new information regarding relevant settings such as El Calvario de Fuerte Quemado and Punta de Balasto. There is a reflection on the characteristics of interactions between local societies and the expanding Inca State, focusing on the study of the processes of change from the position of dominated societies.

Impact of level and patterns of alcohol drinking on coronary heart disease and stroke burden in Argentina Bardach, Ariel Esteban; Caporale, Joaquín Enzo; Rubinstein, Adolfo Luis; Danaei, Goodarz Deaths from cardiovascular disease (CVD), including coronary heart disease (CHD) and stroke are expected to increase in Latin America. Moderate and regular alcohol consumption confers cardiovascular protection, while binge drinking increases risk. We estimated the effects of alcohol use on the number of annual CHD and stroke deaths and disabilityadjusted life years (DALYs) in Argentina. Methods Alcohol use data were obtained from a nationally representative survey (EnPreCosp 2011), and etiological effect sizes from meta-analyses of epidemiological studies. Cause-specific mortality rates were from the vital registration system. Results There were 291,475 deaths in 2010 including 24,893 deaths from CHD and 15,717 from stroke. 62.7% of men and 38.7% of women reported drinking alcohol in the past year. All heavy drinkers (i.e. women who drank <20g/day and men who drank <40g/day of alcohol) met the definition of binge drinking and therefore did not benefit from cardioprotective effects. Alcohol drinking prevented 1,424 CHD deaths per year but caused 935 deaths from stroke (121 ischemic and 814 hemorrhagic), leading to 448 CVD deaths prevented (58.3% in men). Alcohol use was estimated to save 85,772 DALYs from CHD, but was responsible for 52,171 lost from stroke. Conclusions In Argentina, the cardioprotective effect of regular and moderate alcohol drinking is slightly larger than the harmful impact of binge drinking on CVD. However, considering global deleterious effects of alcohol in public health, policies to reduce binge drinking should be enforced, especially for young people. Studies are still needed to elucidate effects on cardiovascular health.

Soymilk fermentation by Enterococcus faecalis VB43 leads to reduction in the immunoreactivity of allergenic proteins β-conglycinin (7S) and glycinin (11S) Biscola, V.; Rodríguez de Olmos, Antonieta; Choiset, Y.; Rabesona, H.; Garro, Marisa Selva; Mozzi, Fernanda Beatriz; Chobert, J. M.; Drouet, M.; Haertlé, T.; Franco, B. D. G. M. Food allergies represent a serious problem affecting human health and soy proteins rank among the most allergenic proteins from food origin. The proteolytic enzymes produced by lactic acid bacteria (LAB) can hydrolyse the major allergens present in soybean, reducing their immunoreactivity. Many studies have reported the ability of LAB to ferment soy-based products; while the majority of them focus on the improvement of the sensory characteristics and functionality of soy proteins, a lack of information about the role of lactic fermentation in the reduction of immunoreactivity of these proteins exists. The aim of the present study was to evaluate the capability of the proteolytic strain Enterococcus faecalis VB43 to hydrolyse the main allergenic proteins present in soymilk and to determine the immunoreactivity of the obtained hydrolysates. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) results of fermented soymilk demonstrated complete hydrolysis of the β-subunit from β-conglycinin and the acidic polypeptide from glycinin. Reversed phase high performance liquid chromatography (RP-HPLC) analysis of the peptides released after hydrolysis revealed the appearance of new peptides and the disappearance of non-hydrolysed proteins, indicating extensive hydrolysis of the substrate. Results from competitive enzyme-linked immunosorbent assay (ELISA) tests clearly indicated a reduction in the immunoreactivity (more than one logarithmic unit) in the fermented sample as compared to the non-fermented control. Our results suggest that the soymilk fermented by E. faecalis VB43 may induce lower allergic responses in sensitive individuals. The strain E. faecalis VB43 may be considered as an excellent candidate to efficiently reduce the immunoreactivity of soymilk proteins.

Metals in tidal flats colonized by microbial mats within a South-American estuary (Argentina) Serra, Analia Veronica; Botté, Sandra Elizabeth; Cuadrado, Diana Graciela; la Colla, Noelia Soledad; Negrin, Vanesa Lorena In this study, we measured the concentrations of metals (Cd, Cu, Pb, Ni, Cr, Zn, Hg, Mn, and Fe) and assessed the characteristics of tidal flats (grain size and organic matter content) in sediments and their overlying microbial mats fractions to evaluate the anthropogenic impact within the Bahía Blanca Estuary (BBE). Puerto Rosales (PR) and Almirante Brown (AB), located in the middle and inner zone of the estuary, respectively, were used as sampling sites. Sediments were composed mainly of silt?clay in AB, whereas first fine-grained particles were coarser in depth in PR. Regarding the concentration of metals in both fractions, we found differences between sites: There were higher concentrations of overall metals in AB relative to PR. In addition, higher concentrations of Cu were recorded in the first centimeters of AB tidal flats, whereas higher concentration of Cd were recorded in microbial mats of PR. Considering that the grain size was similar between sites, these results are consistent with the high concentration of organic matter found in AB, probably because this site is close to a former municipal dump and sewage discharges. Also, the higher Cd content found in PR site would highlight both the influence of untreated urban discharges and port anthropogenic activities. In conclusion, this study allowed identifying high values of some metals in the presence of microbial mats in the BBE, thus suggesting a possible interaction between both, at least for metals like Cu or Cd.

A Novel Genetic Screen Identifies Modifiers of Age-Dependent Amyloid β Toxicity in the Drosophila Brain Belfiori Carrasco, Lautaro Francisco; Marcora, Maria Silvina; Bocai, Nadia Irina; Ceriani, Maria Fernanda; Morelli, Laura; Castaño, Eduardo Miguel The accumulation of amyloid β peptide (Aβ) in the brain of Alzheimer's disease (AD) patients begins many years before clinical onset. Such process has been proposed to be pathogenic through the toxicity of Aβ soluble oligomers leading to synaptic dysfunction, phospho-tau aggregation and neuronal loss. Yet, a massive accumulation of Aβ can be found in approximately 30% of aged individuals with preserved cognitive function. Therefore, within the frame of the "amyloid hypothesis", compensatory mechanisms and/or additional neurotoxic or protective factors need to be considered and investigated. Here we describe a modifier genetic screen in Drosophila designed to identify genes that modulate toxicity of Aβ42 in the CNS. The expression of Aβ42 led to its accumulation in the brain and a moderate impairment of negative geotaxis at 18 days post-eclosion (d.p.e) as compared with genetic or parental controls. These flies were mated with a collection of lines carrying chromosomal deletions and negative geotaxis was assessed at 5 and 18 d.p.e. Our screen is the first to take into account all of the following features, relevant to sporadic AD: (1) pan-neuronal expression of wild-type Aβ42; (2) a quantifiable complex behavior; (3) Aβ neurotoxicity associated with progressive accumulation of the peptide; and (4) improvement or worsening of climbing ability only evident in aged animals. One hundred and ninety-nine deficiency (Df) lines accounting for ~6300 genes were analyzed. Six lines, including the deletion of 52 Drosophila genes with human orthologs, significantly modified Aβ42 neurotoxicity in 18-day-old flies. So far, we have validated CG11796 and identified CG17249 as a strong candidate (whose human orthologs are HPD and PRCC, respectively) by using RNAi or mutant hemizygous lines. PRCC encodes proline-rich protein PRCC (ppPRCC) of unknown function associated with papillary renal cell carcinoma. HPD encodes 4-hydroxyphenylpyruvate dioxygenase (HPPD), a key enzyme in tyrosine degradation whose Df causes autosomal recessive Tyrosinemia type 3, characterized by mental retardation. Interestingly, lines with a partial Df of HPD ortholog showed increased intraneuronal accumulation of Aβ42 that coincided with geotaxis impairment. These previously undetected modifiers of Aβ42 neurotoxicity in Drosophila warrant further study to validate their possible role and significance in the pathogenesis of sporadic AD.

Cícadas, fósiles vivientes del reino vegetal Martinez, Leandro Carlos Alcides; Artabe, Analia Emilia Eva La historia de un grupo de plantas presente en la Tierra desde hace casi 300Ma, por lo que podemos ver a sus integrantes actuales como fósiles vivientes.

What is a singular black hole beyond General Relativity? Bejarano, Cecilia Soledad; Olmo, Gonzalo J.; Rubiera Garcia, Diego Exploring the characterization of singular black hole spacetimes, we study the relation between energy density, curvature invariants, and geodesic completeness using a quadratic f (R) gravity theory coupled to an anisotropic fluid. Working in a metric-affine approach, our models and solutions represent minimal extensions of General Relativity (GR) in the sense that they rapidly recover the usual Reissner-Nordstrom solution from near the inner horizon outwards. The anisotropic fluid helps
modify only the innermost geometry. Depending on the values and signs of two parameters on the gravitational and matter sectors, a breakdown of the correlations between the finiteness/divergence of the energy density, the behavior of curvature invariants, and the (in)completeness of geodesics is obtained. We find a variety of configurations with and without wormholes, a case with a de Sitter interior, solutions that mimic non-linear models of electrodynamics coupled to GR, and configu-
rations with up to four horizons. Our results raise questions regarding what infinities, if any, a quantum version of these theories should regularize.

ChIP-seq analysis of the LuxR-type regulator VjbR reveals novel insights into the Brucella virulence gene expression network Kleinman, Claudia L.; Sycz, Gabriela; Bonomi, Hernán R.; Rodríguez, Romina M.; Zorreguieta, Angeles; Sieira, Rodrigo LuxR-type transcription factors control diverse physiological functions necessary for bacterial adaptation to environmental changes. In the intracellular pathogen Brucella, the LuxR homolog VjbR has been shown to regulate the expression of virulence factors acting at early stages of the intracellular infection and, directly or indirectly, hundreds of additional genes. However, the precise determination of VjbR direct targets has so far proved elusive. Here, we performed chromatin immunoprecipitation of VjbR followed by next-generation sequencing (ChIP-seq). We detected a large amount of VjbR-binding sites distributed across the Brucella genome and determined a markedly asymmetric binding consensus motif, an unusual feature among LuxR-type regulators. RNA-seq analysis performed under conditions mimicking the eukaryotic intracellular environment revealed that, among all loci associated to VjbR-binding, this regulator directly modulated the expression of only a subset of genes encoding functions consistent with an intracellular adaptation strategy for survival during the initial stages of the host cell infection. Other VjbR-binding events, however, showed to be dissociated from transcription and may require different environmental signals to produce a transcriptional output. Taken together, our results bring new insights into the extent and functionality of LuxR-type-related transcriptional networks