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Sobre la conjetura de Lazer-McKenna en el caso no local con potencial superlineal bajo condición de simetría parcial en el dominio: Caso crítico y supercrítico
(Universidad de Chile, 2019)
método de Lyapunov-Schmidt para reducir el proble-
ma a uno finito-dimensional. Además se buscará poder estudiar también el comportamiento
asintótico de las soluciones encontras y su concentración.
1
Laplaciano fraccionario
Gran atención ha tenido...
∗s − 1), con 2∗s = 2NN−2s y φ1 es la primer función positiva del laplaciano fraccionario con condición Dirichlet en el borde. Su principal resultado recae en la prueba de la conjetura para el problema (−∆)su = |u|p − σφ1 en Ω u = 0 en RN \ Ω u...
∗s − 1), con 2∗s = 2NN−2s y φ1 es la primer función positiva del laplaciano fraccionario con condición Dirichlet en el borde. Su principal resultado recae en la prueba de la conjetura para el problema (−∆)su = |u|p − σφ1 en Ω u = 0 en RN \ Ω u...
Efecto de los aerosoles en la radiación solar y la producción fotovoltaica en Santiago
(Universidad de Chile, 2016)
despejado en Santiago para los años 2014-2015 . 61
xi
xii
Índice de Ilustraciones
2.1. Espectro radiativo solar en el tope de la atmósfera, a nivel del mar e irradiancia
calculada según la ley de Planck . . . . . . . . . . . . . . . . . . . . . . . . . 5
2...
a 6000 ◦K calculado con la ley de Planck. Figura 2.1: Espectro de la radiación solar en el tope de la atmósfera, a nivel del mar e irradiancia calculada según la ley de Planck. Fuente : Adaptado de [3]. Cuando se habla del espectro radiativo se hace...
a 6000 ◦K calculado con la ley de Planck. Figura 2.1: Espectro de la radiación solar en el tope de la atmósfera, a nivel del mar e irradiancia calculada según la ley de Planck. Fuente : Adaptado de [3]. Cuando se habla del espectro radiativo se hace...
Estudio de la secreción de Tax, su interacción con Calreticulina y sSEMA-4D en linfocitos infectados con HTLV-I y su efecto sobre las actividades quinásicas y fosfatásicas en células PC12 durante su diferenciación a tipo neuronal
(Universidad de Chile, 2012-12)
de células T del adulto (ATL), una neoplasia agresiva. El HTLV-I infecta principalmente linfocitos T CD4+. No se ha detectado infección por HTLV-I en neuronas, desconociéndose el mecanismo por medio del cual se produce la neurodegeneración en HAM...
The HTLV-I (Human T-cell Lymphotropic Virus Type-I) may cause two diseases, the HTLV-I Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP), a neurodegenerative central axonopathy with axonal transport failure, and the Adult T-cell Leukemia (ATL), an aggressive neoplasia. HTLV-I infects mainly CD4+ T lymphocytes. No evidence of neuron infection with HTLV-I has been detected, therefore the molecular mechanisms associated with the neurodegeneration in HAM/TSP remain unclear. Viral products secreted from infected lymphocytes infiltrated in the central nervous system may affect intracellular pathways related with axonal cytoskeleton producing damage in HAM/TSP patients. Secreted products from MT2 cells (lymphocytes infected with HTLV-I) decrease the rate of neurite growth of PC12 cells at the third day of differentiation to neuronal type. The viral protein Tax is strongly associated with HAM/TSP progression. The decrease in neuritic length of PC12 cells could be mediated either by Tax or by other proteins secreted from these lymphocytes, for example sSEMA-4D (soluble Semaphorin 4D) that serves as negative axonal guide being capable of producing detention of the axonal outgrowth. This soluble protein is generated by the proteolytic release of the membrane-bound SEMA-4D by Matrix Metaloproteinases (MMPs). In HTLV-I infected lymphocytes there is an imbalance in the activities of MMPs and their tissular inhibitors that could produce a large extent of sSEMA-4D, causing detention of the axonal outgrowth. Also, Tax interacts with the endoplasmic reticulum chaperone Calreticulin (CRT) in infected lymphocytes, although it is unknown if this interaction is maintained once Tax is secreted. In this Thesis we proposed that “Secreted Tax protein from HTLV-I infected lymphocytes, complexed with Calreticulin and/or soluble SEMA-4D, reduces the neuritic length during PC12 differentiation to neuronal type, associated with an increase of kinase activities (CDK5, GSK3β) and a decrease in phosphatase activity (PP2A)”. The objectives include to study: a) the mechanism of Tax and CRT secretion; b) the existence of extracellular interaction between Tax, CRT and sSEMA-4D; c) the effect of Tax, CRT and sSEMA-4D on the neuronal differentiation process of PC12 cell line, and d) whether extracellular Tax produces in PC12 cells changes in activities of the kinases CDK5 and GSK3β, and the phosphatase PP2A. The results showed a positive correlation between secreted Tax and CRT amounts determined by Western-blot in Peripheral Blood Mononuclear Cells (PBMCs) of HAM/TSP patients. This secretion was dependent of the Endoplasmic Reticulum–Golgi Apparatus pathway. We identified interaction of Tax with both sSEMA-4D and CRT in the culture medium of PBMCs from HAM/TSP patients. Antibody-mediated blocking demonstrated the participation of both Tax and sSEMA-4D in neurite length decrease of PC12 cells cultured with conditioned media of HTLV-I infected lymphocytes (MT2 cells conditioned media). Respect to kinase and phosphatase activity participation, we determined that in PC12 cells cultured with MT2 conditioned media, GSK3ß activity was not altered, while that of CDK5 was diminished, finding also a lower ratio of phosphorylated PP2A at Y307 (inactivating phosphorylation) that suggests an increase in its phosphatase activity. These results agree with the lower phosphorylation at T181 of Tau, substrate of both CDK5 and PP2A. Although these results do not support the proposed hypothesis, the reduction on CDK5 activity and higher phosphatase activity also may be involved with the reduction of PC12 neuritic length in response to products secreted by HTLV-I infected lymphocytes. This effect could be mediated by the participation of sSEMA-4D and Tax. In consideration of the identified interaction between them, the results open the possibility that they are acting together as a complex on Plexin receptors (Semaphorin receptors) giving us new insights about the mechanism by which the HTLV-I produces HAM/TSP in infected patients....
The HTLV-I (Human T-cell Lymphotropic Virus Type-I) may cause two diseases, the HTLV-I Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP), a neurodegenerative central axonopathy with axonal transport failure, and the Adult T-cell Leukemia (ATL), an aggressive neoplasia. HTLV-I infects mainly CD4+ T lymphocytes. No evidence of neuron infection with HTLV-I has been detected, therefore the molecular mechanisms associated with the neurodegeneration in HAM/TSP remain unclear. Viral products secreted from infected lymphocytes infiltrated in the central nervous system may affect intracellular pathways related with axonal cytoskeleton producing damage in HAM/TSP patients. Secreted products from MT2 cells (lymphocytes infected with HTLV-I) decrease the rate of neurite growth of PC12 cells at the third day of differentiation to neuronal type. The viral protein Tax is strongly associated with HAM/TSP progression. The decrease in neuritic length of PC12 cells could be mediated either by Tax or by other proteins secreted from these lymphocytes, for example sSEMA-4D (soluble Semaphorin 4D) that serves as negative axonal guide being capable of producing detention of the axonal outgrowth. This soluble protein is generated by the proteolytic release of the membrane-bound SEMA-4D by Matrix Metaloproteinases (MMPs). In HTLV-I infected lymphocytes there is an imbalance in the activities of MMPs and their tissular inhibitors that could produce a large extent of sSEMA-4D, causing detention of the axonal outgrowth. Also, Tax interacts with the endoplasmic reticulum chaperone Calreticulin (CRT) in infected lymphocytes, although it is unknown if this interaction is maintained once Tax is secreted. In this Thesis we proposed that “Secreted Tax protein from HTLV-I infected lymphocytes, complexed with Calreticulin and/or soluble SEMA-4D, reduces the neuritic length during PC12 differentiation to neuronal type, associated with an increase of kinase activities (CDK5, GSK3β) and a decrease in phosphatase activity (PP2A)”. The objectives include to study: a) the mechanism of Tax and CRT secretion; b) the existence of extracellular interaction between Tax, CRT and sSEMA-4D; c) the effect of Tax, CRT and sSEMA-4D on the neuronal differentiation process of PC12 cell line, and d) whether extracellular Tax produces in PC12 cells changes in activities of the kinases CDK5 and GSK3β, and the phosphatase PP2A. The results showed a positive correlation between secreted Tax and CRT amounts determined by Western-blot in Peripheral Blood Mononuclear Cells (PBMCs) of HAM/TSP patients. This secretion was dependent of the Endoplasmic Reticulum–Golgi Apparatus pathway. We identified interaction of Tax with both sSEMA-4D and CRT in the culture medium of PBMCs from HAM/TSP patients. Antibody-mediated blocking demonstrated the participation of both Tax and sSEMA-4D in neurite length decrease of PC12 cells cultured with conditioned media of HTLV-I infected lymphocytes (MT2 cells conditioned media). Respect to kinase and phosphatase activity participation, we determined that in PC12 cells cultured with MT2 conditioned media, GSK3ß activity was not altered, while that of CDK5 was diminished, finding also a lower ratio of phosphorylated PP2A at Y307 (inactivating phosphorylation) that suggests an increase in its phosphatase activity. These results agree with the lower phosphorylation at T181 of Tau, substrate of both CDK5 and PP2A. Although these results do not support the proposed hypothesis, the reduction on CDK5 activity and higher phosphatase activity also may be involved with the reduction of PC12 neuritic length in response to products secreted by HTLV-I infected lymphocytes. This effect could be mediated by the participation of sSEMA-4D and Tax. In consideration of the identified interaction between them, the results open the possibility that they are acting together as a complex on Plexin receptors (Semaphorin receptors) giving us new insights about the mechanism by which the HTLV-I produces HAM/TSP in infected patients....
Evaluación analítico-experimental del uso de fibras de polipropileno y acero como refuerzo en sostenimientos de hormigón proyectado para túneles interestación del Metro de Santiago
(Universidad de Chile, 2016)
Esta memoria evalúa analítica y experimentalmente el uso de fibras de acero y/o polipropileno como reemplazo del refuerzo tradicional de mallas electrosoldadas en sostenimientos de hormigón proyectado para los túneles interestación del Metro de...
El Artículo 76 del Código de Procedimiento Civil : análisis empírico y propuesta de lege ferenda
(Universidad de Chile, 2012)
las actuaciones procesales. Adicionalmente, se planteará la adopción de una nueva institucionalidad en materia de asistencia y cooperación internacional que opere a nivel local y coordine a los sujetos involucrados en el diligenciamiento de los...
Convenciones probatorias: aplicación, alcance y límites en el sistema procesal penal chileno
(Universidad de Chile, 2020)
aprensiones que éstas mantienen respecto a dicho
mecanismo.
Así, nuestra tesis se detendrá en primer lugar en desarrollar el concepto de
la verdad y la búsqueda de esta como una finalidad del proceso. Nos
adentraremos acerca del debate doctrinario y...
, lo que se conoce también con el término de verdad como correspondencia. 1.2. PROBLEMAS RESPECTO AL CONCEPTO DE VERDAD. Como hemos podido apreciar, la definición del término verdad, desde el primer momento nos presenta una problemática, debido...
, lo que se conoce también con el término de verdad como correspondencia. 1.2. PROBLEMAS RESPECTO AL CONCEPTO DE VERDAD. Como hemos podido apreciar, la definición del término verdad, desde el primer momento nos presenta una problemática, debido...
Las moléculas HLA-DR que expresan alelos del epítopo compartido, favorecen la presentación de péptidos de alta afinidad derivados de proteínas en tejido y fluido sinovial de pacientes con artritis reumatoide
(Universidad de Chile, 2016)
Estudiamos el peptidoma asociado a la molécula HLA-DR, tanto en tejido sinovial de pacientes con artritis reumatoide (AR) como en células dendríticas (CD) de donantes positivos para alelos del epítopo compartido (EC), pulsadas con fluido sinovial de...
This study involves the peptidome associated to HLA-DR molecule, in synovial tissue from Rheumatoid Arthritis (RA) patients and dendritic cells (DC) from healthy donors positive for shared epitope (SE) alleles pulsed with synovial fluid from RA patients. These alleles have been extensively studied, finding an association with RA. We using _-mass spectrometric-_ peptide repertoire describe some alleles of EC, obtained from tissue and CDs from healthy donors pulsed with FS. Based on the type of binding of these peptide sequences and their origin, we see own of these alleles, they exhibited one more akin to theoretical peptide sequences binding characteristics. This will enable us in the near future the development of a search for new potential autoantigens for this disease. Methodology: 3 RA patients selected for joint replacement surgery were recruited, genotyped for HLA-DR gene, and their synovial fluid and tissue were obtained. Also, healthy donors positive for SE alleles were recruited. From the 100 selected subjects, blood samples were obtained to generate DC, which were pulsed with synovial fluid from RA patients or left unpulsed. HLA-DR/peptides complexes were isolated from tissue and cells, later the peptides which were sequenced by mass spectrometry were eluted and analyzed by bioinformatics tools. Results: 1176 peptides from 227 parental proteins were obtained. Most peptides were presented in nested set and derived from proteins processed by the endocytic pathway. In the case of synovial tissue, most peptides derive from the extracellular medium, whereas in DC, 70% were derived from the plasma membrane. Most peptides presented by SE alleles DRB1*01:01 and DRB1*04:01 in synovial tissue were defined as of high and intermediate affinity for their respective HLA-DR allele. In DC, the peptides presented by the allele DRB1*01:01 had a high theoretical affinity for this allele. No citrullinated peptides were detected neither in synovial tissue nor in pulsed and non-pulsed DC. Conclusion: The peptidome associated to HLA - DR molecule of alleles SE presents peptide sequences with high theoretical affinity. The sequences presented in tissues derived from the extracellular medium and interacting with inflammatory proteins. The sequences presented in healthy donor CDs mostly come from plasma membrane proteins and are related to processing and antigen presentation....
This study involves the peptidome associated to HLA-DR molecule, in synovial tissue from Rheumatoid Arthritis (RA) patients and dendritic cells (DC) from healthy donors positive for shared epitope (SE) alleles pulsed with synovial fluid from RA patients. These alleles have been extensively studied, finding an association with RA. We using _-mass spectrometric-_ peptide repertoire describe some alleles of EC, obtained from tissue and CDs from healthy donors pulsed with FS. Based on the type of binding of these peptide sequences and their origin, we see own of these alleles, they exhibited one more akin to theoretical peptide sequences binding characteristics. This will enable us in the near future the development of a search for new potential autoantigens for this disease. Methodology: 3 RA patients selected for joint replacement surgery were recruited, genotyped for HLA-DR gene, and their synovial fluid and tissue were obtained. Also, healthy donors positive for SE alleles were recruited. From the 100 selected subjects, blood samples were obtained to generate DC, which were pulsed with synovial fluid from RA patients or left unpulsed. HLA-DR/peptides complexes were isolated from tissue and cells, later the peptides which were sequenced by mass spectrometry were eluted and analyzed by bioinformatics tools. Results: 1176 peptides from 227 parental proteins were obtained. Most peptides were presented in nested set and derived from proteins processed by the endocytic pathway. In the case of synovial tissue, most peptides derive from the extracellular medium, whereas in DC, 70% were derived from the plasma membrane. Most peptides presented by SE alleles DRB1*01:01 and DRB1*04:01 in synovial tissue were defined as of high and intermediate affinity for their respective HLA-DR allele. In DC, the peptides presented by the allele DRB1*01:01 had a high theoretical affinity for this allele. No citrullinated peptides were detected neither in synovial tissue nor in pulsed and non-pulsed DC. Conclusion: The peptidome associated to HLA - DR molecule of alleles SE presents peptide sequences with high theoretical affinity. The sequences presented in tissues derived from the extracellular medium and interacting with inflammatory proteins. The sequences presented in healthy donor CDs mostly come from plasma membrane proteins and are related to processing and antigen presentation....
Búsqueda de objetos mediante conocimiento semántico en ambientes interiores
(Universidad de Chile, 2015)
En este trabajo se propone un nuevo enfoque probabilístico para la búsqueda informada de objetos mediante robots. La metodología está basada en un marco bayesiano que usa convoluciones entre verosimilitudes de observación y máscaras de relación...
Resolución de algunos problemas de valor de frontera considerando nuevas ecuaciones constitutivas no lineales para materiales piezoeléctricos
(Universidad de Chile, 2020)
En el presente trabajo se estudian nuevas ecuaciones constitutivas no lineales para cuerpos electroelásticos que no son de Green, donde la deformación y polarización son funciones explícitas del esfuerzo y el campo eléctrico, específicamente para el...
Entrega de malas noticias en la práctica clínica
(Sociedad Medica de Santiago, 2014)
tiempo11.
El cómo la notica es discutida o conversada
con el paciente puede afectar la comprensión de
la información3,12-15, del pronóstico de la enferme-
dad14-15, la satisfacción con la atención médica15-16,
el nivel de esperanza frente a la...
tiene que gradualmente movilizar la atención del paciente hacia los hechos preocupantes que él ahora debe comenzar a comunicar10. La comunicación abierta entre el profesional de la salud y su paciente es crítica para desarrollar una relación...
tiene que gradualmente movilizar la atención del paciente hacia los hechos preocupantes que él ahora debe comenzar a comunicar10. La comunicación abierta entre el profesional de la salud y su paciente es crítica para desarrollar una relación...