207 research outputs found

    Modelos de caminos óptimos entre la cuenca superior y media del río Santa Cruz (Santa Cruz, Argentina)

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    The aim of this paper is to evaluate potential sectors of pedestrian fording of the Santa Cruz River (Santa Cruz province) by modeling least-cost paths in the context of Geographic Information System (GIS). Different variables are utilized, such as: slope, basaltic cover, water sources, depth levels of the Santa Cruz River, and the presence of banks and islands. We evaluate optimal paths among the following archaeological sites located in the Santa Cruz River basin: La Laurita 1 (upper basin, northern margin), Bi Aike 3 (middle basin, northern margin), Yaten Guajen 12 (middle basin, northern margin) and Chorrillo Malo 2 (upper basin, southern margin). These sites share late Holocene chronologies and the presence of black obsidian lithic artifacts. This is a raw material that, according to available evidence, originates from areas located to the north of the basin. The results of the human circulation models are compared with information that was not used for the generation of this model, such as the distribution of surface and stratigraphical archaeological record documented for the area, as well as data obtained from historical accounts.El objetivo de este trabajo consiste en evaluar potenciales sectores de cruce pedestre del río Santa Cruz (provincia de Santa Cruz) mediante el modelado de caminos de menor costo energético en el marco de un Sistema de Información Geográfica (SIG). Para ello se cruzan diferentes variables: pendiente del terreno, cobertura de basalto, fuentes de agua, niveles de profundidad del río Santa Cruz y presencia de bancos e islas. Se evalúan los caminos óptimos entre sitios arqueológicos de la margen norte y sur de la cuenca del río Santa Cruz: La Laurita 1 (cuenca superior, margen norte), Bi Aike 3 (cuenca media, margen norte), Yaten Guajen 12 (cuenca media, margen norte) y Chorrillo Malo 2 (cuenca superior, margen sur). Estos sitios comparten cronologías del Holoceno tardío y la presencia de artefactos líticos de obsidiana negra, materia prima que de acuerdo con la evidencia disponible provendría de áreas localizadas al norte de la cuenca. Los resultados obtenidos se comparan con la distribución del registro arqueológico superficial y estratigráfico previamente detectado, no utilizado para la generación del modelo, como así también con los sectores de paso del río mencionados por cronistas para momentos históricos

    Infecção por virus sincicial respiratório: o papel dos anticorpos séricos específicos

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    INTRODUCTION: Respiratory syncytial virus (RSV) is a major etiological agent of lower respiratory tract infection in infants. Genotypes of this virus and the role of the infants' serum antibodies have yet to be fully clarified. This knowledge is important for the development of effective therapeutic and prophylactic measures. OBJECTIVES: To evaluate the types and genotypes of RSV causing respiratory tract infection in infants, to analyze the association of subtype-specific serum antibodies with the occurrence of infection and to evaluate the presence of subtype-specific antibodies in the infants' mothers and their association with the profile of the childrens' serum antibodies. METHODS: This was a prospective study on infants hospitalized with respiratory infection. Nasopharyngeal secretions were collected for viral investigation using indirect immunofluorescence and viral culture and blood was collected to test for antibodies using the Luminex Multiplex system. RESULTS: 192 infants were evaluated, with 60.9% having RSV (73.5%- A and 20.5% B). Six genotypes of the virus were identified: A5, A2, B3, B5, A7 and B4. The seroprevalence of the subtype-specific serum antibodies was high. The presence and levels of subtype-specific antibodies were similar, irrespective of the presence of infection or the viral type or genotype. The mothers' antibody profiles were similar to their infants'. CONCLUSIONS: Although the prevalence of subtype-specific antibodies was elevated, these antibodies did not provide protection independently of virus type/genotype. The similarity in the profiles of subtype-specific antibodies presented by the mothers and their children was consistent with transplacental passage.INTRODUÇÃO: O vírus sincicial respiratório é um dos principais agentes etiológicos das infecções do aparelho respiratório inferior em lactentes. Os genótipos deste vírus e o papel dos anticorpos séricos ainda não estão esclarecidos. Este conhecimento é importante para o desenvolvimento de medidas terapêuticas e profiláticas. OBJETIVOS: Avaliar: os tipos e genótipos do vírus sincicial que causam infecção respiratória em lactentes e a associação dos anticorpos séricos subtipo-específicos com a ocorrência de infecção; a presença de anticorpos subtipo-específicos nas mães e sua associação com o perfil de anticorpos da criança. MÉTODOS: Estudo prospectivo incluindo lactentes hospitalizados com infecção respiratória. Foi coletada secreção de nasofaringe para investigação viral usando imunofluorescência indireta e cultivo viral. Foi coletado sangue para pesquisa de anticorpos usando o sistema Luminex Multiplex. RESULTADOS: Avaliados 192 lactentes: 60,9% com vírus sincicial (73,5% - A e 20,5% - B). Seis genótipos de vírus sincicial respiratório foram identificados: A5,A2,B3,B5,A7 e B4. A soroprevalência dos anticorpos subtipos-específicos foi alta. A presença e o nível de anticorpos subtipos-específicos foram semelhantes, independentemente da presença de infecção, tipo e genótipo do vírus. As mães e as crianças apresentaram perfis semelhantes de anticorpos. CONCLUSÕES: A prevalência dos anticorpos subtipos-específicos foi elevada mas estes anticorpos não conferiram proteção, independentemente do tipo/genótipo do vírus. A semelhança dos perfis de anticorpos das mães e das crianças foi compatível com transmissão transplacentária

    Análise da relação Brasil-Estados Unidos no agronegócio.

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    Between the Deseado Massif and the north Santa Cruz river basin (Patagonia, Argentina): geochemical analysis on obsidian artifacts and human circulation models

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    El objetivo de este trabajo es evaluar la posibilidad de la existencia de una fuente desconocida de obsidiana entre el sur del Macizo del Deseado y la margen norte de la cuenca del río Santa Cruz (Patagonia, Argentina). La alta frecuencia de obsidiana en algunos sectores de este espacio y la mención de pobladores locales acerca de la existencia de fuentes desconocidas hasta el momento llevaron a la necesidad de explorar esta hipótesis. Se realizaron análisis geoquímicos mediante fluorescencia de rayos X a una muestra de 20 artefactos de obsidiana. Los resultados indican una composición geoquímica similar a las fuentes secundarias de Pampa del Asador, su cono aluvial y 17 de Marzo o sectores intermedios entre ellas, lo que debilita la hipótesis acerca de la existencia de una fuente de obsidiana con una composición diferente en este sector del espacio. Por otra parte, a efectos de comenzar a evaluar cuál de las fuentes habría sido utilizada en cada caso, se hicieron análisis de frecuencia artefactual y se modelaron caminos óptimos entre cañadones que desembocan al norte del río Santa Cruz y las fuentes de obsidiana negra conocidas. Si bien se requieren análisis adicionales, los resultados sugieren la utilización de obsidiana de 17 de Marzo en los espacios más orientales (cañadón Yaten Guajen).The purpose of this paper is to analyze the possibility of the existence of an unknown obsidian source between the south of the Deseado Massif and the northern shore of the Santa Cruz River basin (Patagonia, Argentina). The high frequency of obsidian in some of the analyzed spaces and the information provided by local inhabitants about the existence of an unknown obsidian source in the area, pointed to the need of evaluating this hypothesis. Geochemical analysis, through X-ray fluorescence, were performed on 20 obsidian artifacts recovered in different spaces of the study area. The results indicate a geochemical composition similar to the secondary sources of Pampa del Asador, its alluvial cone, and 17 de Marzo or intermediate sectors between them, which weakens the hypothesis of the existence of an unknown obsidian source with a different composition in this area. In addition, in order to evaluate which of the obsidian sources was used, obsidian artifacts frequencies were utilized and least cost paths were modeled between canyons in the northern shore of Santa Cruz river and the known black obsidian sources. Although further analysis need to be performed, results suggest the utilization of the 17 Marzo source in easterly spaces (Yaten Guajen canyon).Fil: Franco, Nora Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Multidisciplinario de Historia y Ciencias Humanas; ArgentinaFil: Glascock, Michael D. University of Missouri; Estados UnidosFil: MacDonald, Brandi L.. University of Missouri; Estados UnidosFil: Gilio, Brenda Ludmila. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Tecnológica Nacional. Facultad Regional Santa Cruz. Centro de Investigaciones y Transferencia de Santa Cruz. Universidad Nacional de la Patagonia Austral. Centro de Investigaciones y Transferencia de Santa Cruz; Argentin

    Breath analysis for early detection of malignant pleural mesothelioma: Volatile organic compounds (VOCs) determination and possible biochemical pathways

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    Malignant pleural mesothelioma (MPM) is a rare neoplasm, mainly caused by asbestos exposure, with a high mortality rate. The management of patients with MPM is controversial due to a long latency period between exposure and diagnosis and because of non-specific symptoms generally appearing at advanced stage of the disease. Breath analysis, aimed at the identification of diagnostic Volatile Organic Compounds (VOCs) pattern in exhaled breath, is believed to improve early detection of MPM. Therefore, in this study, breath samples from 14 MPM patients and 20 healthy controls (HC) were collected and analyzed by Thermal Desorption-Gas Chromatography-Mass Spectrometry (TD-GC/MS). Nonparametric test allowed to identify the most weighting variables to discriminate between MPM and HC breath samples and multivariate statistics were applied. Considering that MPM is an aggressive neoplasm leading to a late diagnosis and thus the recruitment of patients is very difficult, a promising data mining approach was developed and validated in order to discriminate between MPM patients and healthy controls, even if no large population data are available. Three different machine learning algorithms were applied to perform the classification task with a leave-one-out cross-validation approach, leading to remarkable results (Area Under Curve AUC = 93%). Ten VOCs, such as ketones, alkanes and methylate derivates, as well as hydrocarbons, were able to discriminate between MPM patients and healthy controls and for each compound which resulted diagnostic for MPM, the metabolic pathway was studied in order to identify the link between VOC and the neoplasm. Moreover, five breath samples from asymptomatic asbestos-exposed persons (AEx) were exploratively analyzed, processed and tested by the validated statistical method as blinded samples in order to evaluate the performance for the early recognition of patients affected by MPM among asbestos-exposed persons. Good agreement was found between the information obtained by gold-standard diagnostic methods such as computed tomography CT and model output

    Cerebrospinal fluid levels of L-glutamate signal central inflammatory neurodegeneration in multiple sclerosis

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    Excessive extracellular concentrations of L-glutamate (L-Glu) can be neurotoxic and contribute to neurodegenerative processes in multiple sclerosis (MS). The association between cerebrospinal fluid (CSF) L-Glu levels, clinical features, and inflammatory biomarkers in patients with MS remains unclear. In 179 MS patients (relapsing remitting, RR, N = 157; secondary progressive/primary progressive, SP/PP, N = 22), CSF levels of L-Glu at diagnosis were determined and compared with those obtained in a group of 40 patients with non-inflammatory/non-degenerative disorders. Disability at the time of diagnosis, and after 1 year follow-up, was assessed using the Expanded Disability Status Scale (EDSS). CSF concentrations of lactate and of a large set of pro-inflammatory and anti-inflammatory molecules were explored. CSF levels of L-Glu were slightly reduced in MS patients compared to controls. In RR-MS patients, L-Glu levels correlated with EDSS after 1 year follow-up. Moreover, in MS patients, significant correlations were found between L-Glu and both CSF levels of lactate and the inflammatory molecules interleukin (IL)-2, IL-6, and IL-1 receptor antagonist. Altered expression of L-Glu is associated with disability progression, oxidative stress, and inflammation. These findings identify CSF L-Glu as a candidate neurochemical marker of inflammatory neurodegeneration in MS. (Figure presented.)

    Cerebrospinal fluid levels of L-glutamate signal central inflammatory neurodegeneration in multiple sclerosis

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    Excessive extracellular concentrations of L-glutamate (L-Glu) can be neurotoxic and contribute to neurodegenerative processes in multiple sclerosis (MS). The association between cerebrospinal fluid (CSF) L-Glu levels, clinical features, and inflammatory biomarkers in patients with MS remains unclear. In 179 MS patients (relapsing remitting, RR, N = 157; secondary progressive/primary progressive, SP/PP, N = 22), CSF levels of L-Glu at diagnosis were determined and compared with those obtained in a group of 40 patients with non-inflammatory/non-degenerative disorders. Disability at the time of diagnosis, and after 1 year follow-up, was assessed using the Expanded Disability Status Scale (EDSS). CSF concentrations of lactate and of a large set of pro-inflammatory and anti-inflammatory molecules were explored. CSF levels of L-Glu were slightly reduced in MS patients compared to controls. In RR-MS patients, L-Glu levels correlated with EDSS after 1 year follow-up. Moreover, in MS patients, significant correlations were found between L-Glu and both CSF levels of lactate and the inflammatory molecules interleukin (IL)-2, IL-6, and IL-1 receptor antagonist. Altered expression of L-Glu is associated with disability progression, oxidative stress, and inflammation. These findings identify CSF L-Glu as a candidate neurochemical marker of inflammatory neurodegeneration in MS. (Figure presented.)

    Cdc42 localized in the CatSper signaling complex regulates cAMP‐dependent pathways in mouse sperm

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    Sperm acquire the ability to fertilize in a process called capacitation and undergo hyperactivation, a change in the motility pattern, which depends on Ca2+ transport by CatSper channels. CatSper is essential for fertilization and it is subjected to a complex regulation that is not fully understood. Here, we report that similar to CatSper, Cdc42 distribution in the principal piece is confined to four linear domains and this localization is disrupted in CatSper1-null sperm. Cdc42 inhibition impaired CatSper activity and other Ca2+-dependent downstream events resulting in a severe compromise of the sperm fertilizing potential. We also demonstrate that Cdc42 is essential for CatSper function by modulating cAMP production by soluble adenylate cyclase (sAC), providing a new regulatory mechanism for the stimulation of CatSper by the cAMP-dependent pathway. These results reveal a broad mechanistic insight into the regulation of Ca2+ in mammalian sperm, a matter of critical importance in male infertility as well as in contraception.Fil: 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: Xu, Xinran. State University of Colorado - Fort Collins; Estados UnidosFil: Romarowski, Ana. 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; Argentina. State University of Colorado - Fort Collins; Estados UnidosFil: Gervasi, María G.. University of Massachussets; Estados UnidosFil: Orta, Gerardo. Universidad Autonoma de México. Instituto de Biotecnología; MéxicoFil: De la Vega Beltrán, José L.. Universidad Autonoma de México. Instituto de Biotecnología; MéxicoFil: Stival, Cintia Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Gilio, Nicolás. 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: D'alotto Moreno, Tomas. 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: Krapf, Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Visconti, Pablo E.. University of Massachussets; Estados UnidosFil: Krapf, Diego. State University of Colorado - Fort Collins; Estados UnidosFil: Darszon, Alberto. Universidad Autonoma de México. Instituto de Biotecnología; MéxicoFil: Buffone, Mariano Gabriel. 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
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