Transporte : Espacios periurbanos

Contenidos: - Procesos de producción y consumo de tierra urbana en la periferia del Área Metropolitana de Buenos Aires. El caso del municipio de Almirante Brown 1948-1992 | Claudia Bevilacqua de Cristino - Consideraciones sobre el levantamiento de los ramales ferroviarios y su incidencia sobre un área piloto de la provincia de Buenos Aires | Beatriz Plot y María Julia BelloFacultad de Humanidades y Ciencias de la Educación (FAHCE

Gestión del cambio organizacional mediante la metodología del modelo Adkar para la adaptación al trabajo remoto como contingencia por la pandemia producto del virus Covid-19.

El presente artículo de revisión, es una recopilación bibliográfica de las principales teorías y autores que describen el proceso de gestión de cambio organizacional teniendo en cuenta como prioridad los recursos humanos con los que cuentan las diferentes empresas y de cómo gestionar la adaptabilidad al trabajo remoto de los colaboradores, dadas las contingencias producto de la pandemia por Covid-19 ; en primera medida se empieza por hacer conceptualización del trabajo remoto y a la virtualización de los procesos, seguido a ello, se define el concepto de gestión de cambio, sus elementos y algunos modelos propuestos por diversos autores. Finalmente se ofrece un marco metodológico basado en el modelo ADKAR que pretende servir como guía o parámetro general susceptible de ser implementado en cualquier organización teniendo en cuenta su misión, visión, valores y necesidad de optar por la modalidad de trabajo remoto o teletrabajo.This review article is a bibliographic compilation of the main theories and authors that describes the organizational change management process, taking into account the human resources that different companies have as a priority and how to manage the adaptability to remote work of the collaborators, given the contingencies resulting from the Covid-19 pandemic; In the first measure, it will begin by conceptualizing remote work and virtualizing processes, followed by the concept of change management, exchange rates, their elements and some models proposed by various authors. Finally, a methodological framework based on the ADKAR model will be offered, which aims to serve as a guide or general parameter that can be implemented in any organization, taking into account its mission, vision, values and the need to opt for the remote work or telework modality.Resumen. -- Introducción y justificación. -- Trabajo remoto, teletrabajo. -- Gestión del cambio. -- Modelo Adkar. -- Conclusiones. -- Referencias

Structural and functional integrity of endocrine pancreas post administration of Karwinskia humboldtiana fruit to Wistar rats: a possible therapeutic application for cancer of exocrine origin

Aims. Pancreatic adenocarcinoma represents a therapeutic challenge due to the high toxicity of antineoplastic treatments and secondary effects of pancreatectomy. T-514, a toxin isolated from Karwinskia humboldtiana (Kh) has shown antineoplastic activity on cell lines. In acute intoxication with Kh, we reported apoptosis on the exocrine portion of pancreas. One of the mechanisms of antineoplastic agents is the induction of apoptosis, therefore our main objective was to evidence structural and functional integrity of the islets of Langerhans after the administration of Kh fruit in Wistar rats. Methods. TUNEL assay and immunolabelling against activated caspase-3 were used to detect apoptosis. Also, immunohistochemical tests were performed to search for glucagon and insulin. Serum amylase enzyme activity was also quantified as a molecular marker of pancreatic damage. Results. Evidence of toxicity on the exocrine portion, by positivity in the TUNEL assay and activated caspase-3, was found. On the contrary, the endocrine portion remained structurally and functionally intact, without apoptosis, and presenting positivity in the identification of glucagon and insulin. Conclusions. These results demonstrated that Kh fruit induces selective toxicity on the exocrine portion and establish a precedent to evaluate T-514 as a potential treatment against pancreatic adenocarcinoma without affecting the islets of Langerhans

Incertidumbre en la determinación del Porcentaje Volumétrico de Bloques de BIMrocks/BIMsoil a partir de información unidimensional

The mechanical characterization of the deposits of heterogeneous materials (BIMrocks/BIMsoil – Block in Matrix) requires the knowledge of the number of embedded blocks within a weaker matrix (Proportion of Volumetric Blocks, PVB). The randomness in the process of formation of such deposits does not allow to obtain univocal information through the conventional geotechnical survey.  It is possible to recognize that as the number and depth of the borehole increase, the uncertainty of the determination of the PVB decrease. However, the quantification of the decrease of uncertainty has not been fully covered. The determination of the PVB in materials BIMrock/BIMsoil has associated an uncertainty that have been studied with physical and analytical models. Such models do not consider the influence of factors like the size, shape and the blocks orientation, that simultaneously affect in the quantification of the uncertainties in the PVB.  In this work a computational algorithm has been developed and implemented to analyze the influence of the length and number of borehole, the shape and orientation of the blocks, on the uncertainty level of the determination of the PVB. The results suggest that further investigations of the subsoil (number and length of the perforations), independently of the shape, size and orientation of the blocks, the less is the epistemic uncertainty in the PVB. Nevertheless, it has been found that such uncertainty has an inferior limit that obeys the randomly natural formation of the material BIMrock/BIMsoil.  La caracterización mecánica de depósitos de materiales heterogéneos (BIMrocks/BIMsoil – Block in Matrix) requiere del conocimiento de la cantidad de bloques inmersos en una matriz débil (Proporción Volumétrica de Bloques, PVB). La aleatoriedad en el proceso de formación de dichos depósitos impide obtener información unívoca mediante estudios geotécnicos convencionales.  Es posible reconocer que a medida que aumenta el número y la profundidad de las perforaciones, se disminuye la incertidumbre en la determinación de la PVB, sin embargo, la cuantificación de la disminución de la incertidumbre no ha sido abarcada de manera comprensiva. La determinación de la PVB en materiales BIMrock/BIMsoil tiene asociada una incertidumbre que se ha estudiado con modelos físicos y analíticos. Dichos modelos no consideran la influencia de factores como el tamaño, forma y orientación de los bloques, que simultáneamente inciden en la cuantificación de la incertidumbre en la PVB. En este trabajo se desarrolló un algoritmo y se implementó computacionalmente para analizar la influencia de la longitud y el número de las perforaciones, junto con la forma y orientación de los bloques, sobre el nivel de incertidumbre en la determinación de la PVB. Los resultados sugieren que a mayor investigación del subsuelo (número y longitud de perforaciones), independiente de la forma, tamaño y orientación de los bloques, se disminuye la incertidumbre epistémica en la PVB. Sin embargo, dicha incertidumbre tiene un límite inferior que obedece a la naturaleza aleatoria propia de la formación del material BIMrock/BIMsoil

Analytical Performance of a Multiplex Real-Time PCR Assay Using TaqMan Probes for Quantification of Trypanosoma cruzi Satellite DNA in Blood Samples

Background: The analytical validation of sensitive, accurate and standardized Real-Time PCR methods for Trypanosoma cruzi quantification is crucial to provide a reliable laboratory tool for diagnosis of recent infections as well as for monitoring treatment efficacy. Methods/Principal Findings: We have standardized and validated a multiplex Real-Time quantitative PCR assay (qPCR) based on TaqMan technology, aiming to quantify T. cruzi satellite DNA as well as an internal amplification control (IAC) in a single-tube reaction. IAC amplification allows rule out false negative PCR results due to inhibitory substances or loss of DNA during sample processing. The assay has a limit of detection (LOD) of 0.70 parasite equivalents/mL and a limit of quantification (LOQ) of 1.53 parasite equivalents/mL starting from non-boiled Guanidine EDTA blood spiked with T. cruzi CLBrener stock. The method was evaluated with blood samples collected from Chagas disease patients experiencing different clinical stages and epidemiological scenarios: 1- Sixteen Venezuelan patients from an outbreak of oral transmission, 2- Sixty three Bolivian patients suffering chronic Chagas disease, 3- Thirty four Argentinean cases with chronic Chagas disease, 4- Twenty seven newborns to seropositive mothers, 5- A seronegative receptor who got infected after transplantation with a cadaveric kidney explanted from an infected subject. Conclusions/Significance: The performing parameters of this assay encourage its application to early assessment of T. cruzi infection in cases in which serological methods are not informative, such as recent infections by oral contamination or congenital transmission or after transplantation with organs from seropositive donors, as well as for monitoring Chagas disease patients under etiological treatment.Fil: Duffy, Tomas. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones En Ingeniería Genética y Biología Molecular; ArgentinaFil: Cura, Carolina Inés. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Ramírez, Juan C.. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Abate, Teresa. Universidad Central de Venezuela. Instituto de Medicina Tropical; VenezuelaFil: Cayo, Nelly M.. Universidad Nacional de Jujuy. Instituto de Biologia de la Altura; ArgentinaFil: Parrado, Rudy. Universidad San Simón; BoliviaFil: Diaz Bello, Zoraida. Universidad Central de Venezuela. Instituto de Medicina Tropical; VenezuelaFil: Velazquez, Elsa Beatriz. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Muñoz Calderón, Arturo. Universidad Central de Venezuela. Instituto de Medicina Tropical; VenezuelaFil: Juiz, Natalia Anahí. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Basile, Joaquín. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; ArgentinaFil: Garcia, Lineth. Universidad San Simón; BoliviaFil: Riarte, Adelina. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud. Instituto Nacional de Parasitología; ArgentinaFil: Nasser, Julio Rubén. Universidad Nacional de Salta. Facultad de Ciencias Naturales; ArgentinaFil: Ocampo, Susana B.. Universidad Nacional de Jujuy. Instituto de Biologia de la Altura; ArgentinaFil: Yadon, Zaida E.. Pan-American Health Organization; Estados UnidosFil: Torrico, Faustino. Universidad San Simón; BoliviaFil: Alarcón de Noya, Belkisyole. Universidad Central de Venezuela. Instituto de Medicina Tropical; VenezuelaFil: Ribeiro, Isabela. Drugs and Neglected Diseases Initiative; SuizaFil: Schijman, Alejandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular; Argentin

The CXC-Chemokine CXCL4 Interacts with Integrins Implicated in Angiogenesis

The human CXC-chemokine CXCL4 is a potent inhibitor of tumor-induced angiogenesis. Considering that CXCL4 is sequestered in platelet α-granules and released following platelet activation in the vicinity of vessel wall injury, we tested the hypothesis that CXCL4 might function as a ligand for integrins. Integrins are a family of adhesion receptors that play a crucial role in angiogenesis by regulating early angiogenic processes, such as endothelial cell adhesion and migration. Here, we show that CXCL4 interacts with αvβ3 on the surface of αvβ3-CHO. More importantly, human umbilical vein endothelial cells adhere to immobilized CXCL4 through αvβ3 integrin, and also through other integrins, such as αvβ5 and α5β1. We further demonstrate that CXCL4-integrin interaction is of functional significance in vitro, since immobilized CXCL4 supported endothelial cell spreading and migration in an integrin-dependent manner. Soluble CXCL4, in turn, inhibits integrin-dependent endothelial cell adhesion and migration. As a whole, our study identifies integrins as novel receptors for CXCL4 that may contribute to its antiangiogenic effect

Responsabilidad objetiva fundamentada en la teoría del riesgo

S/

Effect of PEX, a Noncatalytic Metalloproteinase Fragment with Integrin-Binding Activity, on Experimental Chlamydophila pneumoniae Infection

Chlamydophila pneumoniae is a pathogen that is involved in acute and chronic respiratory infections and that is associated with asthma and coronary artery diseases. In this study, we evaluated the effects of PEX, a noncatalytic metalloproteinase fragment with integrin-binding activity, against experimental infections caused by C. pneumoniae. Moreover, we investigated the relationships between C. pneumoniae and α(v)β(3) integrin functions in order to explain the possible mechanism of action of PEX both in vitro and in vivo. For the in vitro experiments, HeLa cells were infected with C. pneumoniae and treated with either PEX or azithromycin. The results obtained with PEX were not significantly different (P > 0.05) from those achieved with azithromycin. Similar results were also obtained in a lung infection model. Male C57BL/J6 mice inoculated intranasally with 10(6) inclusion-forming units of C. pneumoniae were treated with either PEX or azithromycin plus rifampin. Infected mice treated with PEX showed a marked decrease in C. pneumoniae counts versus those for the controls; this finding did not differ significantly (P > 0.05) from the results observed for the antibiotic-treated group. Integrin α(v)β(3) plays an important role in C. pneumoniae infection. Blockage of integrin activation led to a significant inhibition of C. pneumoniae infection in HeLa cells. Moreover, CHO(DHFR) α(v)β(3)-expressing cells were significantly (P < 0.001) more susceptible to C. pneumoniae infection than CHO(DHFR) cells. These results offer new perspectives on the treatment of C. pneumoniae infection and indicate that α(v)β(3) could be a promising target for new agents developed for activity against this pathogen