21 resultados
Resultados de la búsqueda
Mostrando 1 - 10 de 21
Ítem Echocardiographic assessment of valve prostheses in the pediatric population(Sociedad Colombiana de Cardiologia y Cirugia Cardiovascular, 2014-01-01) Santos, Raúl D.En niños con insuficiencia o estenosis valvular significativa, la intervención de la válvula, ya sea valvuloplastia o reemplazo valvular, suele ser inevitable. El seguimiento de estos pacientes puede ser complejo; los síntomas iniciales de disfunción valvular protésica son inespecíficos y en ocasiones es difícil diferenciar entre los efectos de la disfunción valvular, las patologías no cardíacas, la disfunción ventricular y la hipertensión pulmonar. Aunque el examen físico puede alertar al clínico acerca de alteraciones, se requieren otros métodos diagnósticos para evaluar la función de la prótesis. La ecocardiografía Doppler es el método de elección no invasivo para estudiar la función valvular y pese a que muchas de las mediciones y parámetros de normalidad y anormalidad son extrapolados de estudios en adultos, se han tratado de definir estándares en pacientes pediátricos. Este documento ofrece una revisión acerca de las técnicas usadas en el estudio de las válvulas protésicas con base en literatura científica, consensos internacionales y opiniones de expertos.
Ítem Comparative evaluation of adhesion formation of prosthetic meshes after intra-abdominal implantation in wistar rats / Evaluación comparativa de la formación de adherencias de mallas protésicas después de la implantación intraabdominal en ratas(IEEE, 2012-04-07) Arboleda, A.Increasingly biomaterials for the repair of abdominal wall defects are used. The aim of this study was to evaluate adhesion formation of prosthetic meshes after intraabdominal implantation to repair a surgical defect in the anterior abdominal wall. This anatomical defect was repaired by one of the three types of previously sterilized meshes: 1) fibroin 2) fibroin with polyethylene glycol and 3) commercial polypropylene mesh as control. The grip score was significantly higher in the commercial polypropylene mesh. Fibroin is a promising biomaterial for treating defects of the abdominal wall. © 2014 IEEE.Ítem Liver Angiosarcoma: Rare tumour associated with a poor prognosis, literature review and case report(Elsevier Ltd, 2016-09-29) Millan, Mauricio I.We report a case of minimally invasive nephrectomy of a kidney transplanted into the abdominal cavity in a child. A 15-year-old girl underwent transplantation with a cadaveric donor kidney due to congenital pyelonephritis, vesicoureteral reflux, and secondary bladder atrophy. The transplant was complicated by hyperacute rejection, cytomegalovirus infection, and anastomotic stenosis of the Bricker neobladder. After recurrent urinary tract infections, the patient was reintroduced to hemodialysis in 2010. After pneumo-peritoneum, we placed 2 10-mm trocars in the hypochondrium and left side and 2 5-mm in the left iliac fossa and right upper quadrantÍtem Liver transplantation for unresectable metastases from colon adenocarcinoma(S. Karger AG, 2016-10-06) Caicedo, Luis ArmandoLiver transplantation is an option that improves quality of life and prolongs life expectancy in patients with different types of liver disease. Liver transplantation is controversial for colorectal metastases and is not recommended in clinical practice guidelines. In this case report, we present, to our knowledge, the first liver transplantation for colorectal metastases conducted in Colombia, with a successful follow-up of more than 2 years. Patients with these characteristics who underwent liver transplantation experience reduced mortality and exponentially improved quality of life.Ítem Genetically-Engineered Pig-to-Baboon Liver Xenotransplantation: Histopathology of Xenografts and Native Organs(Public Library of Science, 2012-01-11) Echeverri Junca, Gabriel JaimeOrthotopic liver transplantation was carried out in baboons using wild-type (WT, n = 1) or genetically-engineered pigs (a1,3- galactosyltransferase gene-knockout, GTKO), n = 1; GTKO pigs transgenic for human CD46, n = 7) and a clinically-acceptable immunosuppressive regimen. Biopsies were obtained from the WT pig liver pre-Tx and at 30 min, 1, 2, 3, 4 and 5 h posttransplantation. Biopsies of genetically-engineered livers were obtained pre-Tx, 2 h after reperfusion and at necropsy (4–7 days after transplantation). Tissues were examined by light, confocal, and electron microscopy. All major native organs were also examined. The WT pig liver underwent hyperacute rejection. After genetically-engineered pig liver transplantation, hyperacute rejection did not occur. Survival was limited to 4–7 days due to repeated spontaneous bleeding in the liver and native organs (as a result of profound thrombocytopenia) which necessitated euthanasia. At 2 h, graft histology was largely normal. At necropsy, genetically-engineered pig livers showed hemorrhagic necrosis, platelet aggregation, platelet-fibrin thrombi, monocyte/macrophage margination mainly in liver sinusoids, and vascular endothelial cell hypertrophy, confirmed by confocal and electron microscopy. Immunohistochemistry showed minimal deposition of IgM, and almost absence of IgG, C3, C4d, C5b-9, and of a cellular infiltrate, suggesting that neither antibody- nor cell-mediated rejection played a major role.Ítem A Syndrome of Severe Hypoglycemia and Acidosis in Young Immunosuppressed Diabetic Monkeys and Pigs—Association With Sepsis(Wolters Kluwer Health, Inc., 2012-12-27) Echeverri Junca, Gabriel JaimeBackground: Large animals treated with immunosuppressive drugs for preclinical experiments of transplantation have increased risks of infection, which can be compounded by the induction of diabetes if islet transplantation is planned. Methods: We report our experience with severe sepsis in two young cynomolgus monkeys and five pigs that were subjected to diabetes induction, immunosuppressive therapy, or islet allotransplantation. Results: In two monkeys and five pigs, infection was associated with a syndrome of profound hypoglycemia accompanied by severe acidosis, which was resistant to treatment. We do not believe that this syndrome has been reported previously by others. Conclusions: Despite treatment, this syndrome complicated the interpretation of blood glucose readings as a measure of islet graft function and resulted in death or the need for euthanasia in all seven animals. We tentatively suggest that the syndrome may be related to the presence of microorganisms that metabolize glucose and produce lactate.Ítem T-Cell-Based Immunosuppressive Therapy Inhibits the Development of Natural Antibodies in Infant Baboons(2012-04-27) Echeverri Junca, Gabriel JaimeBackground. We set out to determine whether B-cell tolerance to A/B-incompatible alloantigens and pig xenoantigens could be achieved in infant baboons. Methods. Artery patch grafts were implanted in the abdominal aorta in 3-month-old baboons using A/B-incompatible (AB-I) allografts or wild-type pig xenografts (pig). Group 1 (Gp1) (controls, n=6) received no immunosuppressive therapy (IS) and no graft. Gp2 (n=2) received an AB-I or pig graft but no IS. Gp3 received AB-I grafts+IS (Gp3A: n=2) or pig grafts+IS (Gp3B: n=2). IS consisted of ATG, anti-CD154mAb, and mycophenolate mofetil until age 8 to 12 months. Gp4 (n=2) received IS only but no graft. Results. In Gp1, anti-A/B and cytotoxic anti-pig immunoglobulin-M increased steadily during the first year. Gp2 became sensitized to donor-specific AB-I or pig antigens within 2 weeks. Gp3 and Gp4 infants that received anti-CD154mAb made no or minimal anti-A/B and anti-pig antibodies while receiving IS.Ítem The Charlson comorbidity index as a predictor of outcomes in liver transplantation: single-center experience.(Universidad Icesi, 2012-06-01) Echeverri Junca, Gabriel JaimeSeveral comorbidity indices, such as the Child-Turcotte-Pugh (CTP) score and the Model for End-Stage Liver Disease (MELD) score, have been used to optimize available organ resources and adjust priorities in diagnosis and allocation of grafts for patients who are candidates for liver transplantation. There have also been various attempts to create instruments to accurately predict outcomes after liver transplantation, but none has proved to be truly applicable, with the exception of the Charlson comorbidity index (CCI). We retrospectively reviewed data of 221 liver recipients, including living-related liver transplantation and multiple organ transplantation performed between January 2006 and September 2009. Survival analysis revealed a significant association of the CCI with decreased posttransplantation patient survival (P = .003). Furthermore, Kaplan-Meier plots and log-rank test showed a significant association between graft survival and the score (P = .039). Our data suggest that the CCI is a simple tool for the evaluation of comorbidity and that increased preoperative patient comorbidity increases the risk of graft loss and patient death after liver transplantation. The CCI should be considered an important tool for improving patient care because of its potential applications for patient management.Ítem Potential factors influencing the development of thrombocytopenia and consumptive coagulopathy after genetically modified pig liver xenotransplantation.(Wiley, 2012-01-01) Cooper, David KC C.Upregulation of tissue factor (TF) expression on activated donor endothelial cells (ECs) triggered by the immune response (IR) has been considered the main initiator of consumptive coagulopathy (CC). In this study, we aimed to identify potential factors in the development of thrombocytopenia and CC after genetically engineered pig liver transplantation in baboons. Baboons received a liver from either an α1,3-galactosyltransferase gene-knockout (GTKO) pig (n = 1) or a GTKO pig transgenic for CD46 (n = 5) with immunosuppressive therapy. TF exposure on recipient platelets and peripheral blood mononuclear cell (PBMCs), activation of donor ECs, platelet and EC microparticles, and the IR were monitored. Profound thrombocytopenia and thrombin formation occurred within minutes of liver reperfusion. Within 2 h, circulating platelets and PBMCs expressed functional TF, with evidence of aggregation in the graft. Porcine ECs were negative for expression of P- and E-selectin, CD106, and TF. The measurable IR was minimal, and the severity and rapidity of thrombocytopenia were not alleviated by prior manipulation of the IR. We suggest that the development of thrombocytopenia/CC may be associated with TF exposure on recipient platelets and PBMCs (but possibly not with activation of donor ECs). Recipient TF appears to initiate thrombocytopenia/CC by a mechanism that may be independent of the IR.Ítem Systemic inflammation in xenograft recipients precedes activation of coagulation.(2015-01-01) Echeverri Junca, Gabriel JaimeBACKGROUND: Dysregulation of coagulation is considered a major barrier against successful pig organ xenotransplantation in non-human primates. Inflammation is known to promote activation of coagulation. The role of pro-inflammatory factors as well as the relationship between inflammation and activation of coagulation in xenograft recipients is poorly understood.
- «
- 1 (current)
- 2
- 3
- »