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Caracterización del daño mecánico de la aorta en condición de hipoxia. Modelamiento y simulación numérica de un ensayo de presurización
(Univ Fed Rio de Janeiro, Brazil, 2021)
presiones asociadas al inicio del daño entregadas por la simulación del ensayo son compatibles
con una condición de hipertensión arterial....
In order to reliably assess the rupture-risk of the aorta – along with the hazardousness index of cardiovascular diseases or other extreme conditions, and the effect of possible treatments – it is necessary to know the damage mechanisms that lead to it. In this work, the mechanical damage of hypoxic aortic tissue is characterized, numerically predicting its response when subjected to a bulge-test type of pressurization state. The mechanical behavior of the aortic wall, is described using a hyperelastic material model with two transverse-isotropy directions and an isotropic damage model; both experimentally calibrated, from previously reported uniaxial tensile-test results, performed on thoracic aorta samples of lambs exposed to chronic hypobaric hypoxia. A melatonin-treated group is studied in contrast to a control group. Once the constitutive model is calibrated, its performance is evaluated via the numerical simulation of the bulge-pressurization test; in which the quasistatic response of a quarter-disk shaped structure, fixed along its curved perimeter, and loaded out of its plane by a pressure, or force per unit area permanently normal to the loaded area, its analyzed. The experimental data and the results of numerical simulations indicate that a melatonin treatment reduces the stiffness of the aorta. Moreover, the group-wise determined pressures, delivered by the bulge-test simula-tion and associated with the onset of damage, are compatible with an arterial hypertensive condition....
In order to reliably assess the rupture-risk of the aorta – along with the hazardousness index of cardiovascular diseases or other extreme conditions, and the effect of possible treatments – it is necessary to know the damage mechanisms that lead to it. In this work, the mechanical damage of hypoxic aortic tissue is characterized, numerically predicting its response when subjected to a bulge-test type of pressurization state. The mechanical behavior of the aortic wall, is described using a hyperelastic material model with two transverse-isotropy directions and an isotropic damage model; both experimentally calibrated, from previously reported uniaxial tensile-test results, performed on thoracic aorta samples of lambs exposed to chronic hypobaric hypoxia. A melatonin-treated group is studied in contrast to a control group. Once the constitutive model is calibrated, its performance is evaluated via the numerical simulation of the bulge-pressurization test; in which the quasistatic response of a quarter-disk shaped structure, fixed along its curved perimeter, and loaded out of its plane by a pressure, or force per unit area permanently normal to the loaded area, its analyzed. The experimental data and the results of numerical simulations indicate that a melatonin treatment reduces the stiffness of the aorta. Moreover, the group-wise determined pressures, delivered by the bulge-test simula-tion and associated with the onset of damage, are compatible with an arterial hypertensive condition....
Consequences of COVID-19 pandemic on myocardial infarction reperfusion therapy and prognosis
(Soc. Médica Santiago, Chile, 2021)
Background: The coronavirus disease (COVID-19) pandemic affected the
prompt diagnosis and treatment of Acute myocardial infarction (AMI). Aim: To
characterize the clinical profile of patients with AMI during the COVID-19
pandemic, comparing them with a historical cohort. Material and Methods: A
case-control study of 96 patients with AMI transferred to a high-volume percutaneous
coronary intervention (PCI) hospital between March and July 2020, and a
historical cohort of 269 patients transferred during the same period in 2019. Results:
When comparing patients transferred during the pandemic with those of the
historical cohort, the former were younger (63 ± 12 vs 68 ± 12 years, p < 0.01), had
a higher frequency of hypertension (66 vs 45%, p < 0.01) and of smoking (40% vs
25%, p < 0.01). Also, during COVID-19 outbreak a higher proportion of patients
had ST-elevation AMI consulting > 12 hours from the onset of symptoms (44 vs
0%, p < 0.01), a higher median door-to-device time (4 vs 3 hours, p < 0.01), a
higher use of primary percutaneous coronary intervention (97 vs 71%, p < 0.01),
and higher frequencies of cardiogenic shock (20 vs 4%, p < 0.01) and mechanical
complications (10% vs 2%, p < 0.01). Patients during COVID pandemic had a
higher thirty-day overall (20 vs 1.4%, p < 0.01) and cardiovascular mortality ( 13
vs 1%, p < 0.01). During the outbreak, 40% of patients had positive COVID-19
status, which was a predictor for thirty-day overall mortality (Risk ratio 2.90;
95% confidence intervals 1.14-7.36). Conclusions: During the pandemic patients
with AMI exhibited delays in consultations and treatment, higher morbidity,
and increased mortality. COVID-19 positivity was associated to worse thirty-day
overall survival....
). Resultados: Al comparar los pacientes transferidos durante pandemia y la cohorte histórica, los primeros eran más jóvenes (63 ± 12 y 68 ± 12 años respectivamente, p < 0,01), tenían una mayor frecuencia de hipertensión (65.6 y 45.1% respectivamente, p < 0...
). Resultados: Al comparar los pacientes transferidos durante pandemia y la cohorte histórica, los primeros eran más jóvenes (63 ± 12 y 68 ± 12 años respectivamente, p < 0,01), tenían una mayor frecuencia de hipertensión (65.6 y 45.1% respectivamente, p < 0...
Micelas de núcleo lipídico (LCMs) para la liberación bucal de un péptido modelo de fármaco antihipertensivo a través de un film polimérico obtenido por inyección de tinta
(Universidad de Chile, 2024)
La hipertensión arterial es una de las enfermedades crónicas no transmisibles más prevalente en el mundo y está dada principalmente por una hiperactividad del eje renina angiotensina. Es un factor de riesgo para el desarrollo de múltiples...
Arterial hypertension is one of the most prevalent non-communicable chronic diseases worldwide, primarily driven by hyperactivity of the renin-angiotensin axis. It constitutes a risk factor for the development of multiple cardiovascular diseases, potentially leading to cardiac structural growth and significant intrinsic vascular changes. Recent studies have characterized the pharmacological activity of a peptide associated with the vasodilator arm of the RAS, Ang 1-9. Through in vitro and in vivo studies, it has demonstrated anti-hypertensive and anti-hypertrophic pharmacological properties. With advancements in nanotechnology and targeted drug delivery systems, lipid core micelles (LCMs) have emerged as colloidal systems with very low toxicity, showing significant results in the administration of other biological drugs. In this thesis project, LCMs associated with the model peptide for an antihypertensive drug were synthesized and inkjet-printed onto an HPMC polymeric film. The synthesized LCMs demonstrated a size smaller than 20 nm, and STEM micrographs revealed their spherical size and shape. Moreover, the formulations' PdI was less than 0.3, indicating formulations with low dispersion, positioning them as a reproducible and homogeneous system. The kinetic stability of the LCMs in suspension was evaluated, demonstrating that, like other colloidal systems, temperature affects the behavior of lipid components, triggering instability mechanisms associated with micellar systems. The mechanical and mucoadhesive properties of the films were assessed, showing an increase in material elasticity after the printing process. Additionally, they maintained sufficient mucoadhesion to remain attached for a defined period. Release profiles were elucidated using dialysis membrane at 37°C. Both suspension and printed LCMs adhered to the Korsmeyer-Peppas kinetic model. Suspension LCMs exhibited an abrupt release within the first 15 minutes. Conversely, the release of printed LCMs was half that of suspension LCMs, displaying a prolonged release associated with the presence of hydrophilic polymer in the formulation. These results indicate that the formulation of printed LCMs on an oral film is a highly plausible formulation capable of administering peptides via the oral route....
Arterial hypertension is one of the most prevalent non-communicable chronic diseases worldwide, primarily driven by hyperactivity of the renin-angiotensin axis. It constitutes a risk factor for the development of multiple cardiovascular diseases, potentially leading to cardiac structural growth and significant intrinsic vascular changes. Recent studies have characterized the pharmacological activity of a peptide associated with the vasodilator arm of the RAS, Ang 1-9. Through in vitro and in vivo studies, it has demonstrated anti-hypertensive and anti-hypertrophic pharmacological properties. With advancements in nanotechnology and targeted drug delivery systems, lipid core micelles (LCMs) have emerged as colloidal systems with very low toxicity, showing significant results in the administration of other biological drugs. In this thesis project, LCMs associated with the model peptide for an antihypertensive drug were synthesized and inkjet-printed onto an HPMC polymeric film. The synthesized LCMs demonstrated a size smaller than 20 nm, and STEM micrographs revealed their spherical size and shape. Moreover, the formulations' PdI was less than 0.3, indicating formulations with low dispersion, positioning them as a reproducible and homogeneous system. The kinetic stability of the LCMs in suspension was evaluated, demonstrating that, like other colloidal systems, temperature affects the behavior of lipid components, triggering instability mechanisms associated with micellar systems. The mechanical and mucoadhesive properties of the films were assessed, showing an increase in material elasticity after the printing process. Additionally, they maintained sufficient mucoadhesion to remain attached for a defined period. Release profiles were elucidated using dialysis membrane at 37°C. Both suspension and printed LCMs adhered to the Korsmeyer-Peppas kinetic model. Suspension LCMs exhibited an abrupt release within the first 15 minutes. Conversely, the release of printed LCMs was half that of suspension LCMs, displaying a prolonged release associated with the presence of hydrophilic polymer in the formulation. These results indicate that the formulation of printed LCMs on an oral film is a highly plausible formulation capable of administering peptides via the oral route....
Envejecimiento cardiovascular
(SOC MEDICA SANTIAGO, 2008-12)
conocidos (hipertensión
arterial, dislipidemia, tabaquismo, diabetes melli-
tus, etc.), la cual facilita el desarrollo de la
enfermedad cardiovascular clínica. En este senti-
do, la modificación cardiovascular del envejeci-
miento se constituye en el mayor...
-media, formándose un círculo vicioso entre estos trastor- nos y el consecuente incremento de la presión sistólica que puede preceder al desarrollo de hipertensión arterial. Es decir, la hipertensión arterial sería, en parte, una enfermedad de la pared arterial y...
-media, formándose un círculo vicioso entre estos trastor- nos y el consecuente incremento de la presión sistólica que puede preceder al desarrollo de hipertensión arterial. Es decir, la hipertensión arterial sería, en parte, una enfermedad de la pared arterial y...
Factores de riesgo asociados al bajo peso al nacer
(Universidad de Chile, 2004)
deficitario (escasa ganancia de peso durante el embarazo y malos controles). En pacientes mayores de 35 años, se plantea que la existencia de patología crónica (diabetes, hipertensión, etc) motivaría adelantar el parto. La preeclampsia es un factor de riesgo...
Caracterización de pacientes con HTA, adherencia, conocimiento de tratamiento y su percepción de calidad de atención en Atención Primaria de Salud
(Universidad de Chile, 2014)
La Hipertensión Arterial (HTA) es una patología que afecta a gran parte de la población chilena, es el principal factor de riesgo de enfermedades del sistema cardiovascular. Se caracteriza por incidir en el aumento de otras patologías concomitantes...
Capacidad funcional y su relación con factores de riesgo cardiovascular en una población de adultos mayores de Ñuñoa
(Universidad de Chile, 2011)
no mostraron asociación estadísticamente significativa entre la capacidad funcional obtenida y factores de riesgo cardiovascular como hipertensión arterial, diabetes, sobrepeso u obesidad y razón cintura estatura >0,55. En conclusión, se observó que la...
The goal of the present study was to evaluate the relationship between functional capacity and cardiovascular risk in an elderly population belonging to a physical activity program for older adults in Ñuñoa’s commune, in Santiago de Chile. Our study is non-experimental, analytical and transversal. The data registering and recollection was conducted on Dicember 2011 with a non probabilistic, made by convenience sample which was established by 81 elderly from both sexs, with ages between 65 and 80 years old, who belong to the program previously described, and that previously met certain inclusion and exclusion criteria. The 6MWT was applied as required by the protocol of the American Thoracic Society. On the results we found no significant relationship between functional capacity and cardiovascular risk factors as obesity, hypertension and diabetes. In conclusion, we found that functional capacity and cardiovascular risk factors doesn’t presents a relationship on an elderly population of Ñuñoa....
The goal of the present study was to evaluate the relationship between functional capacity and cardiovascular risk in an elderly population belonging to a physical activity program for older adults in Ñuñoa’s commune, in Santiago de Chile. Our study is non-experimental, analytical and transversal. The data registering and recollection was conducted on Dicember 2011 with a non probabilistic, made by convenience sample which was established by 81 elderly from both sexs, with ages between 65 and 80 years old, who belong to the program previously described, and that previously met certain inclusion and exclusion criteria. The 6MWT was applied as required by the protocol of the American Thoracic Society. On the results we found no significant relationship between functional capacity and cardiovascular risk factors as obesity, hypertension and diabetes. In conclusion, we found that functional capacity and cardiovascular risk factors doesn’t presents a relationship on an elderly population of Ñuñoa....
Test cardiopulmonar: una herramienta de utilidad diagnóstica y pronóstica
(Sociedad Médica Santiago, 2020)
factores de
riesgo establecidos (tabaquismo, hipertensión,
dislipidemia y diabetes mellitus tipo 2). De acuer-
do con ello, la AHA sugiere que la evaluación de
la ACR debe ser masificada3, siendo la prueba de
ejercicio máximo o test cardiopulmonar (CPET...
bradi-arrítmia, hipertensión arterial grave Presión sistólica > 200 mmHg Presión diastólica > 120 mmHg), enfermedad valvular moderada, enfermedad coronaria Vascular Embolia pulmonar o infarto Hipertensión pulmonar severa Respiratoria Asma no controlada...
bradi-arrítmia, hipertensión arterial grave Presión sistólica > 200 mmHg Presión diastólica > 120 mmHg), enfermedad valvular moderada, enfermedad coronaria Vascular Embolia pulmonar o infarto Hipertensión pulmonar severa Respiratoria Asma no controlada...
Marcadores bioquímicos de estrés oxidativo en la preeclamsia de mujeres chilenas
(Universidad de Chile, 2004)
% de las embarazadas. El cuadro clínico se
caracteriza por una tríada clásica de hipertensión arterial, proteinuria y edema,
que desaparece completamente luego del parto. Su diagnóstico generalmente
se realiza durante la segunda mitad del embarazo...
hipertensión, proteinuria y edema que desaparecen después del parto (Davison et al., 2004). La hipertensión en este caso es definida como un incremento de las cifras de presión arterial sistólica por sobre 140 mm Hg y una presión arterial diastólica por...
hipertensión, proteinuria y edema que desaparecen después del parto (Davison et al., 2004). La hipertensión en este caso es definida como un incremento de las cifras de presión arterial sistólica por sobre 140 mm Hg y una presión arterial diastólica por...
Sarcoidosis subcutánea como manifestación inicial de sarcoidosis sistémica
(Elsevier, 2013)
´nea.
Paciente 1
Mujer de 46 an˜os, con antecedentes de diabetes mellitus
2, hipertensio´n arterial, miastenia gravis e hipotiroidismo.
Consulta por un cuadro de un mes de evolucio´n, caracte-
rizado por aumento de volumen y mu´ ltiples no´dulos
subcuta...