RESUMO
In addition to controlling smooth muscle tone in coronary vessels, endothelial cells also influence subjacent cardiomyocyte growth. Because heparanase, with exclusive expression in endothelial cells, enables extracellular matrix remodeling, angiogenesis, metabolic reprogramming, and cell survival, it is conceivable that it could also encourage development of cardiac hypertrophy. Global heparanase overexpression resulted in physiologic cardiac hypertrophy, likely an outcome of HSPG clustering and activation of hypertrophic signaling. The heparanase autocrine effect of releasing neuregulin-1 could have also contributed to this overexpression. Hyperglycemia induced by streptozotocin-induced diabetes sensitized the heart to flow-induced release of heparanase and neuregulin-1. Despite this excess secretion, progression of diabetes caused significant gene expression changes related to mitochondrial metabolism and cell death that led to development of pathologic hypertrophy and heart dysfunction. Physiologic cardiac hypertrophy was also observed in rats with cardiomyocyte-specific vascular endothelial growth factor B overexpression. When perfused, hearts from these animals released significantly higher amounts of both heparanase and neuregulin-1. However, subjecting these animals to diabetes triggered robust transcriptome changes related to metabolism and a transition to pathologic hypertrophy. Our data suggest that in the absence of mechanisms that support cardiac energy generation and prevention of cell death, as seen after diabetes, there is a transition from physiologic to pathologic cardiac hypertrophy and a decline in cardiac function.
Assuntos
Cardiomegalia , Diabetes Mellitus Experimental , Glucuronidase , Remodelação Ventricular , Animais , Masculino , Ratos , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Diabetes Mellitus Experimental/metabolismo , Glucuronidase/metabolismo , Glucuronidase/genética , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Neuregulina-1/metabolismo , Neuregulina-1/genética , Remodelação Ventricular/fisiologia , FemininoRESUMO
Objetivo: Comparar los resultados posoperatorios clínicos y radiográficos en dos grupos de pacientes: menor o igual a 55 años y mayor a 55 años, sometidos a una artroplastia total de tobillo de tercera generación. Materiales y Métodos: Se evaluó, en forma retrospectiva, a dos grupos de pacientes: menor o igual a 55 años (n = 13) y mayor a 55 años (n = 18), que fueron sometidos a una artroplastia total de tobillo de tercera generación. La edad promedio del grupo de menor o igual a 55 años era 42.8 (DE 6.4) y la del grupo mayor a 55 años, 65.7 (DE 8.8). Resultados: El seguimiento promedio fue de 36 meses (RIC 25-60). La etiología era principalmente postraumática en ambos grupos. El puntaje promedio de la escala AOFAS al año de la cirugía fue 76,69 (RIC 58-89) en el grupo menor o igual a 55 años y 85,22 (RIC 67-100) en el grupo mayor a 55 años. No hubo diferencias estadísticamente significativas entre ambos grupos en los ángulos alfa, beta y gamma; medidos en las radiografías con apoyo a los 2 meses y a los 2 años de la cirugía. Conclusiones: Nuestro estudio demostró que los resultados clínicos y radiográficos en pacientes más jóvenes serían comparables con los de pacientes más grandes en el seguimiento temprano. Se necesita un seguimiento a más largo plazo para determinar si el riesgo de revisión es más alto en los pacientes jóvenes, debido a la falla relacionada con el desgaste de la prótesis
Objective: To compare the clinical and radiographic postoperative outcomes in two groups of patients: younger 55 and older than 55-year patients undergoing a third-generation total ankle arthroplasty (TAA). Materials and Methods: Two groups of patients were retrospectively studied: younger 55 (n=13) and older 55-year patients (n=19) undergoing a third-generation TAA. Group younger 55 average age was 42.8 (SD, 6.4) and Group older 55 average age was 65.7 (SD, 8.8). Results: The average follow-up was 36 months (IQR, 25-60). The main etiology was post-traumatic conditions in both groups. The mean score of the AOFAS scale one year after surgery was 76.69 (IQR, 58-89) in the group younger 55 and 85.22 (IQR, 67-100) in the group older 55. There were no statistically significant differences between the two groups in the alpha, beta and gamma angles measured on weight-bearing radiographs at 2-month and 2-year postoperative controls. Conclusions: Our study shows clinical and radiographic short-term outcomes in younger patients are similar to those in older patients. Longer-term follow-up is warranted to determine if the revision risk is greater in young patients, due to failures related to prosthesis wear
Assuntos
Adulto , Pessoa de Meia-Idade , Idoso , Osteoartrite , Fatores Etários , Resultado do Tratamento , Artroplastia de Substituição do TornozeloRESUMO
La cirugía ortopédica ha avanzado mucho en estos años y, con ello, el uso de la intensificación de imágenes en el quirófano. El objetivo de este informe es revisar los principios biológicos de la radiación, el marco legal actual y hacer una breve reseña sobre la situación actual en la Argentina.
Orthopedic surgery has significantly advanced in the past years along with image intensifier fluoroscopy in the operating room. The purpose of this report is to review biological principles of radiation, as well as the current legal framework and to outline the present situation in Argentina.