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1.
Transplant Proc ; 50(3): 887-890, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29661459

RESUMEN

BACKGROUND: Ureteral obstruction is the most common urological complication of kidney transplantation. Obstruction secondary to ureteral stenosis can be an early or late complication. CASE REPORT: We present a patient in whom ureteral obstruction was initially identified at 2.5 months after transplant for which she underwent a midpole ureterocalycostomy between the midpole calyx of the transplant kidney and the native left ureter.


Asunto(s)
Trasplante de Riñón/efectos adversos , Riñón/cirugía , Uréter/cirugía , Obstrucción Ureteral/etiología , Obstrucción Ureteral/cirugía , Adolescente , Adulto , Constricción Patológica/complicaciones , Femenino , Humanos , Procedimientos Quirúrgicos Robotizados/métodos , Trasplantes/cirugía , Procedimientos Quirúrgicos Urológicos/métodos
2.
Am J Transplant ; 17(6): 1515-1524, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28251816

RESUMEN

Low case volume has been associated with poor outcomes in a wide spectrum of procedures. Our objective was to study the association of low case volume and worse outcomes in pediatric heart transplant centers, taking the novel approach of including waitlist outcomes in the analysis. We studied a cohort of 6482 candidates listed in the Organ Procurement and Transplantation Network for pediatric heart transplantation between 2002 and 2014; 4665 (72%) of the candidates underwent transplantation. Candidates were divided into groups according to the average annual transplantation volume of the listing center during the study period: more than 10, six to 10, three to five, or fewer than three transplantations. We used multivariate Cox regression analysis to identify independent risk factors for waitlist and posttransplantation mortality. Of the 6482 candidates, 24% were listed in low-volume centers (fewer than three annual transplantations). Of these listed candidates in low-volume centers, only 36% received a transplant versus 89% in high-volume centers (more than 10 annual transplantations) (p < 0.001). Listing at a low-volume center was the most significant risk factor for waitlist death (hazard ratio [HR] 4.5, 95% confidence interval [CI] 3.5-5.7 in multivariate Cox regression and HR 5.6, CI 4.4-7.3 in multivariate competing risk regression) and was significant for posttransplantation death (HR 1.27, 95% CI 1.0-1.6 in multivariate Cox regression). During the study period, one-fourth of pediatric transplant candidates were listed in low-volume transplant centers. These children had a limited transplantation rate and a much greater risk of dying while on the waitlist.


Asunto(s)
Rechazo de Injerto/mortalidad , Trasplante de Corazón/mortalidad , Hospitales de Bajo Volumen/estadística & datos numéricos , Complicaciones Posoperatorias , Obtención de Tejidos y Órganos , Listas de Espera , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Supervivencia de Injerto , Humanos , Lactante , Recién Nacido , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
3.
Am J Transplant ; 15(7): 1855-63, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25689873

RESUMEN

A prognostic index to predict survival after liver transplantation could address several clinical needs. Here, we devised a scoring system that predicts recipient survival after pediatric liver transplantation. We used univariate and multivariate analysis on 4565 pediatric liver transplant recipients data and identified independent recipient and donor risk factors for posttransplant mortality at 3 months. Multiple imputation was used to account for missing variables. We identified five factors as significant predictors of recipient mortality after pediatric liver transplantation: two previous transplants (OR 5.88, CI 2.88-12.01), one previous transplant (OR 2.54, CI 1.75-3.68), life support (OR 3.68, CI 2.39-5.67), renal insufficiency (OR 2.66, CI 1.84-3.84), recipient weight under 6 kilograms (OR 1.67, CI 1.12-2.36) and cadaveric technical variant allograft (OR 1.38, CI 1.03-1.83). The Survival Outcomes Following Pediatric Liver Transplant score assigns weighted risk points to each of these factors in a scoring system to predict 3-month recipient survival after liver transplantation with a C-statistic of 0.74. Although quite accurate when compared with other posttransplant survival models, we would not advocate individual clinical application of the index.


Asunto(s)
Determinación de Punto Final/métodos , Hepatopatías/mortalidad , Trasplante de Hígado/mortalidad , Modelos Teóricos , Evaluación de Resultado en la Atención de Salud , Adolescente , Niño , Preescolar , Técnicas de Apoyo para la Decisión , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Hepatopatías/diagnóstico , Hepatopatías/cirugía , Masculino , Análisis Multivariante , Complicaciones Posoperatorias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia
4.
Am J Transplant ; 10(9): 2092-8, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20883543

RESUMEN

The Milan Criteria (MC) showed that orthotopic liver transplantation (OLT) was an effective treatment for patients with nonresectable, nonmetastatic HCC. There is growing evidence that expanding the MC does not adversely affect patient or allograft survival following OLT. The adult OLT programs in UNOS Region 4 reached an agreement allowing lesions outside MC (one lesion <6 cm, ≤3 lesions, none >5 cm and total diameter <9 cm-[R4 T3]) to receive the same exception points as MC lesions. Kaplan-Meier curves and log-rank tests were used to compare survival data. Chi-squared and Mann-Whitney U tests were used to compare patient data. A p-value of <0.05 was considered significant. All statistical analyses were performed on SPSS 15 (SPSS, Chicago, IL). Four hundred and forty-five patients were transplanted for HCC (363-MC and 82-R4 T3). Patient demographics were found to be similar between the two groups. Three year patient, allograft and recurrence free survival between MC and R4 T3 were found to be 72.9% and 77.1%, 71% and 70.2% and 90.5% and 86.9%, respectively (all p > 0.05). We report the first regionalized multicenter, prospective study showing benefit of OLT in patients exceeding MC based on preoperative imaging.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Selección de Paciente , Carcinoma Hepatocelular/mortalidad , Causas de Muerte , Distribución de Chi-Cuadrado , Femenino , Supervivencia de Injerto , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Prospectivos , Trasplante Homólogo
5.
Ir J Med Sci ; 179(4): 605-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20734157

RESUMEN

INTRODUCTION: The liver and biliary tree are common sites of initial metastasis for many primary tumors. However, we recently encountered a patient who presented with biliary-tree tumor encasement as a first metastasis from squamous carcinoma of the anus. METHODS: To our knowledge, this has not been previously described in the literature. CONCLUSIONS: As obstructive jaundice is a relatively common presenting sign in the emergency room and in general surgical clinics, we thus recommend early consideration of metastatic disease as a differential diagnosis in patients post-chemoradiotherapy for anal carcinoma who present with obstructive jaundice.


Asunto(s)
Neoplasias del Ano/patología , Neoplasias del Sistema Biliar/secundario , Carcinoma de Células Escamosas/secundario , Neoplasias del Ano/cirugía , Conductos Biliares/patología , Neoplasias del Sistema Biliar/cirugía , Carcinoma de Células Escamosas/cirugía , Neoplasias del Conducto Colédoco , Dilatación Patológica , Epitelio/patología , Femenino , Humanos , Ictericia Obstructiva/etiología , Yeyunostomía , Persona de Mediana Edad , Conductos Pancreáticos/patología
6.
Transplant Proc ; 37(5): 2263-5, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15964394

RESUMEN

INTRODUCTION: Pancreatic islet transplantation (PIT) has only become an effective treatment for type 1 diabetes mellitus within the past 4 years. As a result, the long-term effects of PIT on progression of diabetic neuropathy and retinopathy are unknown. The benefit of halting or improving diabetic neuropathy and retinopathy is of particular interest since most PIT recipients have not developed the advanced complications of diabetes. Herein, we describe the improvement and stabilization of diabetic neuropathy and retinopathy in 12 PIT recipients. PATIENTS AND METHODS: Between January 1, 2002, and June 30, 2004, there have been 12 patients who have received PIT. Currently, there are eight patients who have sufficient follow-up to assess the progression of diabetic retinopathy and neuropathy. To assess for disease progression, patients were examined by a single ophthalmologist and single neurologist throughout the study period. Eye exams were performed using a slit-lamp exam while neurological status was assessed using electromyelograms and clinical exams. RESULTS: All PIT recipients had decreases in hemoglobin A(1)C and increases in serum C-peptide. All study patients had stabilization of their retinopathic disease. One patient demonstrated improvement of retinopathy at 1 year posttransplant. Fifty percent of patients demonstrated improvement or stabilization of their diabetic neuropathy. One patient had mild reinnervation of the fingers and wrist extensors by clinical exam 1 year posttransplant. Four patients exhibited an average decrease of 19% in sural nerve conduction velocities. CONCLUSION: Our series has demonstrated that all PIT recipients have had stabilization of their diabetic retinopathy and that 50% of patients exhibited stabilization or even improvement of their diabetic neuropathy.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Neuropatías Diabéticas/prevención & control , Retinopatía Diabética/prevención & control , Trasplante de Islotes Pancreáticos/fisiología , Adulto , Péptido C/sangre , Neuropatías Diabéticas/fisiopatología , Retinopatía Diabética/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico
7.
Surgery ; 126(2): 364-70, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10455907

RESUMEN

BACKGROUND: Recent investigation suggests that cyclooxygenase-2 plays an important role in colorectal carcinogenesis. Transforming growth factor-beta1 (TGF-beta 1) is one of the most potent stimulators of cyclooxygenase-2 expression. A key step in intestinal tumorigenesis involves alteration of the normal cellular response to TGF-beta 1. We have hypothesized that overexpression of cyclooxygenase-2 alters intestinal epithelial response to TGF-beta 1. METHODS: RIE-1 cells were stably transfected with rat cyclooxygenase-2 complementary DNA in either the sense (RIE-S) or antisense (RIE-AS) orientation. Tumor cell invasion was assessed with a modified Boyden collagen type I invasion assay in the presence of TGF-beta 1, antibody to urokinase plasminogen activator (uPA), or the selective cyclooxygenase-2 inhibitor SC-58125. Expression of uPA, uPA receptor, and plasminogen activator inhibitor-1 were determined by Western blot and enzyme-linked immunosorbent assay. RESULTS: RIE-1 and RIE-AS did not invade although RIE-S cells were minimally invasive at baseline. TGF-beta 1 had no effect on RIE-1 or RIE-AS invasion; however, TGF-beta 1 significantly upregulated RIE-S cell invasion. All 3 RIE cell lines produce minimal uPA under basal conditions. TGF-beta 1 upregulated uPA production only in the RIE-S cells. Both antibody to uPA and SC-58125 reversed TGF-beta-mediated RIE-S cell invasion. SC-58125 inhibited TGF-beta-mediated RIE-S uPA production. CONCLUSIONS: These results demonstrate that overexpression of cyclooxygenase-2 alters intestinal epithelial response to TGF-beta 1, which may be a mechanism by which cyclooxygenase-2 promotes colon carcinogenesis.


Asunto(s)
Neoplasias Intestinales/patología , Isoenzimas/fisiología , Prostaglandina-Endoperóxido Sintasas/fisiología , Factor de Crecimiento Transformador beta/farmacología , Animales , Células Cultivadas , Ciclooxigenasa 2 , Neoplasias Intestinales/enzimología , Neoplasias Intestinales/etiología , Invasividad Neoplásica , Ratas , Activador de Plasminógeno de Tipo Uroquinasa/biosíntesis
8.
Oncogene ; 18(4): 855-67, 1999 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-10023661

RESUMEN

The precise role of TGF-beta in colorectal carcinogenesis is not clear. The purpose of this study was to determine the phenotypic alterations caused by chronic exposure to TGF-beta in non-transformed intestinal epithelial (RIE-1) cells. Growth of RIE-1 cells was inhibited by >75% following TGF-beta1 treatment for 7 days, after which the cells resumed a normal growth despite the presence of TGF-beta1. These 'TGF-beta-resistant' cells (RIE-Tr) were continuously exposed to TGF-beta for >50 days. Unlike the parental RIE cells, RIE-Tr cells lost contact inhibition, formed foci in culture, grew in soft agarose. RIE-Tr cells demonstrated TGF-beta-dependent invasive potential in an in vitro assay and were resistant to Matrigel and Na-butyrate-induced apoptosis. The RIE-Tr cells were also tumorigenic in nude mice. The transformed phenotype of RIE-Tr cells was associated with a 95% decrease in the level of the type II TGF-beta receptor (TbetaRII) protein, a 40-fold increase in cyclooxygenase-2 (COX-2) protein, and 5.9-fold increase in the production of prostacyclin. Most RIE-Tr subclones that expressed low levels of TbetaRII and high levels of COX-2 were tumorigenic. Those subclones that express abundant TbetaRII and low levels of COX-2 were not tumorigenic in nude mice. A selective COX-2 inhibitor inhibited RIE-Tr cell growth in culture and tumor growth in nude mice. The reduced expression of TbetaRII, increased expression of COX-2, and the ability to form colonies in Matrigel were all reversible upon withdrawal of exogenous TGF-beta1 for the RIE-Tr cells.


Asunto(s)
Transformación Celular Neoplásica/inducido químicamente , Regulación hacia Abajo , Células Epiteliales/efectos de los fármacos , Intestinos/efectos de los fármacos , Isoenzimas/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Animales , Apoptosis , Recuento de Células , División Celular/efectos de los fármacos , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Ciclooxigenasa 2 , Resistencia a Medicamentos , Inducción Enzimática , Células Epiteliales/metabolismo , Intestinos/citología , Fenotipo , Proteínas Serina-Treonina Quinasas , Ratas , Receptor Tipo II de Factor de Crecimiento Transformador beta
9.
J Surg Res ; 77(1): 55-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9698533

RESUMEN

BACKGROUND: Angiostatin, a proteolytic fragment of plasminogen, is a potent inhibitor of angiogenesis. In vitro, angiostatin can be generated by pancreatic elastase proteolysis of plasminogen; however, in vivo, the enzymes responsible for angiostatin production are not known. A recent study demonstrates the involvement of a serine protease in angiostatin generation. In this study we sought to determine if the human pancreatic carcinoma cell line ASPC1 produced enzymatic activity capable of converting plasminogen to angiostatin and to determine if urokinase plasminogen activator (uPA) is involved in this system. Methods. ASPC1 cells were grown to near confluence in 20% FBS-RPMI. Media were changed to serum free and cells cultured for an additional 24 h. The serum free conditioned media (SFCM) was obtained. Angiostatin generation was determined by incubating 20 microg of human plasminogen with 100 microl of SFCM for 0, 3, 8, 12, 24, and 48 h. Plasminogen cleavage was assessed in the presence of the following protease inhibitors: pefabloc, aprotinin, phosphoramidon, leupeptin, and EDTA. The effect of uPA on angiostatin generation was determined by incubating plasminogen with antibody to uPA. Angiostatin generation was determined by Western blot. RESULTS: Incubation of plasminogen with SFCM resulted in the generation of immunoreactive bands at 48 kDa corresponding to human angiostatin. Angiostatin generation by ASPC1 SFCM was time dependent; there was a significant decrease in the plasminogen substrate beginning at 3 h with complete conversion to angiostatin by 48 h. Enzymatic activity leading to angiostatin production was found to be due to a serine protease. Antibody to uPA effectively blocked angiostatin production by ASPC1 SFCM in a dose-dependent manner. CONCLUSION: Human pancreatic cancer cells express enzymatic activity which leads to the generation of angiostatin. Conversion of plasminogen to angiostatin is due to a serine protease. This serine protease is most likely uPA.


Asunto(s)
Neoplasias Pancreáticas/metabolismo , Fragmentos de Péptidos/biosíntesis , Plasminógeno/biosíntesis , Angiostatinas , Aprotinina/farmacología , Medio de Cultivo Libre de Suero/farmacología , Humanos , Plasminógeno/farmacología , Activadores Plasminogénicos/fisiología , Inhibidores de Serina Proteinasa/farmacología , Sulfonas/farmacología , Células Tumorales Cultivadas , Activador de Plasminógeno de Tipo Uroquinasa/fisiología
10.
Surgery ; 124(2): 388-93, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9706163

RESUMEN

BACKGROUND: Angiostatin, a proteolytic fragment of plasminogen, is a potent inhibitor of angiogenesis. We have previously shown that the human pancreatic cancer cell line ASPC-1 produces enzymatic activity capable of generating angiostatin. In this study we sought to determine whether angiostatin production by ASPC-1 cells was regulated by the growth factor transforming growth factor-beta 1 (TGF-beta 1), a key mediator of tumor angiogenesis. METHODS: ASPC-1 cells were grown to 70% to 80% confluence in 20% fetal calf serum-RPMI. Medium was changed to serum free. TGF-beta 1 was added at concentrations of 0, 1, 5, and 10 ng/mL with or without plasminogen activator inhibitor type-1 (PAI-1) at concentrations of 0, 5, 10, 50, and 100 micrograms/mL. Cells were then cultured for an additional 24 hours. The serum-free conditioned medium was obtained. Angiostatin generation was determined by incubating 20 micrograms of plasminogen with 100 microL of serum-free conditioned medium for 0, 1, 2, 3, 6, 12, and 24 hours. Samples were run on 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis and transferred. The membrane was probed with a monoclonal antibody to the kringle 1-3 fragment of plasminogen and developed using enhanced chemiluminescence. RESULTS: TGF-beta 1 and PAI-1 inhibited the conversion of plasminogen into angiostatin in a time- and dose-dependent manner. Antibody to PAI-1 completely blocks TGF-beta 1 mediated angiostatin inhibition. CONCLUSIONS: TGF-beta 1 inhibits the generation of the antiangiogenic molecule angiostatin by human pancreatic cancer cells in a time- and dose-dependent manner. This effect is mediated through modulation of the plasminogen/plasmin system.


Asunto(s)
Antineoplásicos/metabolismo , Neoplasias Pancreáticas , Fragmentos de Péptidos/biosíntesis , Plasminógeno/biosíntesis , Factor de Crecimiento Transformador beta/farmacología , Adenocarcinoma , Angiostatinas , Anticuerpos/farmacología , Antineoplásicos/análisis , Western Blotting , Relación Dosis-Respuesta a Droga , Humanos , Neovascularización Patológica/enzimología , Neovascularización Patológica/fisiopatología , Fragmentos de Péptidos/análisis , Fragmentos de Péptidos/metabolismo , Plasminógeno/análisis , Plasminógeno/metabolismo , Inhibidor 1 de Activador Plasminogénico/inmunología , Inhibidor 1 de Activador Plasminogénico/farmacología , Inhibidores de Serina Proteinasa/inmunología , Inhibidores de Serina Proteinasa/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Células Tumorales Cultivadas/metabolismo
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