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1.
Am Surg ; 65(3): 218-21, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10075295

RESUMEN

An 82-year-old black woman with a history of hepatocellular carcinoma presented with gastrointestinal bleeding. Barium enema and fibrocolonoscopy revealed a 4-cm polypoid mass at the level of the ascending colon with evidence of active bleeding. Biopsies of the lesion proved it to be metastatic hepatocellular carcinoma. Exploratory laparotomy revealed no further dissemination of the tumor, and the patient underwent an ileocolectomy. The serosal side of the colonic lesion was free from tumor, and there was no peritoneal implantation, direct extension, or lymph node involvement. This case represents an extremely rare presentation of metastatic hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/secundario , Neoplasias del Colon/complicaciones , Neoplasias del Colon/secundario , Hemorragia Gastrointestinal/etiología , Neoplasias Hepáticas/patología , Anciano , Anciano de 80 o más Años , Femenino , Humanos
2.
Am Surg ; 63(10): 923-6, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9322674

RESUMEN

Acute liver failure has been reported as a frequent complication of transarterial chemoembolization (TACE). We prospectively evaluated the adverse effects and biochemical changes of TACE. From 10/95 to 9/96, 35 patients with hepatic malignancies were evaluated for TACE. Fifteen patients (9 male and 6 female) received 23 treatments. Ten of 15 patients had hepatocellular carcinoma, and 5 had metastatic tumors. Treatment exclusion criteria included advanced liver disease, hepatic vascular thrombosis, and severe comorbidity. TACE consisted of intra-arterial infusion of a mixture of doxorubicin, cisplatin, and mitomycin followed by embolization. Clinical symptoms and laboratory studies were monitored following treatment. Technical success was achieved in all patients. Adverse symptoms were transient, and most resolved within 1 week. Changes in hepatic, renal, and hematologic function were temporary and returned to pre-TACE levels by 1 month. None developed acute liver failure. The mean hospital stay was 3 days. Ten of 13 patients had a significant decrease in baseline tumor markers. The actual survival was 93 per cent with a median follow-up of 10 months. TACE can be performed safely in patients with hepatic tumors. The adverse effects can be anticipated and easily managed.


Asunto(s)
Quimioembolización Terapéutica/métodos , Neoplasias Hepáticas/terapia , Adulto , Anciano , Antibióticos Antineoplásicos/administración & dosificación , Antineoplásicos/administración & dosificación , Biomarcadores de Tumor/análisis , Tumor Carcinoide/secundario , Tumor Carcinoide/terapia , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/efectos adversos , Cisplatino/administración & dosificación , Doxorrubicina/administración & dosificación , Estudios de Evaluación como Asunto , Femenino , Estudios de Seguimiento , Arteria Hepática , Humanos , Infusiones Intraarteriales , Riñón/fisiopatología , Tiempo de Internación , Hígado/irrigación sanguínea , Hígado/fisiopatología , Hepatopatías , Fallo Hepático Agudo/etiología , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Mitomicinas/administración & dosificación , Selección de Paciente , Estudios Prospectivos , Inducción de Remisión , Seguridad , Tasa de Supervivencia , Trombosis
3.
Liver Transpl Surg ; 3(4): 398-406, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9346770

RESUMEN

Recurrent hepatitis C infection after orthotopic liver transplantation (OLT) is frequent and may occur as early as a few weeks postoperatively. Early histopathological features of recurrent hepatitis C virus (HCV) infection may be modified by immunosuppressive therapy and can be difficult to differentiate from acute allograft rejection (AAR). Thus, we retrospectively compared histopathological features of liver biopsy specimens from two carefully selected patient groups: one with unequivocal recurrent hepatitis C, the other with unequivocal AAR. Index biopsy specimens obtained at the time of the appearance of liver test abnormalities after OLT and all serial liver biopsy specimens (2 to 13 per patient) were assessed under code and scored semiquantitatively for 44 histopathological variables. The index biopsy specimens from patients with recurrent HCV infection and AAR index biopsies (AAR-Ib) differed significantly (P < .05) for 11 features (10 features were statistically associated with AAR and 1 with early recurrence of HCV infection). Statistically significant features associated with AAR included bile duct injury with overlapping nuclei, lymphocytic infiltrates and necrosis, endothelialitis, portal inflammatory infiltrates containing eosinophils and polymorphonuclear leukocytes, hepatocyte mitoses, and zone 3 canalicular cholestasis. In contrast, the only statistically significant feature associated with early recurrent HCV was sinusoidal dilatation. Stepwise discriminant analysis showed that the presence of eosinophils in the portal inflammatory infiltrate, bile duct necrosis, and bile duct lymphocytic infiltrates were independently associated with AAR. However, serial biopsy specimens from patients with recurrent HCV infection showed statistically significant progression in scores for portal inflammation, portal lymphoid aggregates, and lobular inflammation. We conclude that (1) multiple histopathological features are associated with AAR; (2) early recurrent HCV infection is characterized by elevated alanine aminotransferase levels, positive HCV RNA by polymerase chain reaction (PCR), and absence of diagnostic histopathological features; and (3) serial biopsies are needed to demonstrate progression of histopathological features of recurrent hepatitis C.


Asunto(s)
Rechazo de Injerto/patología , Hepatitis C/patología , Trasplante de Hígado/efectos adversos , Enfermedad Aguda , Adulto , Biopsia , Eosinófilos/patología , Rechazo de Injerto/etiología , Rechazo de Injerto/prevención & control , Hepacivirus/genética , Hepacivirus/inmunología , Hepatitis C/etiología , Anticuerpos contra la Hepatitis C/análisis , Humanos , Inmunosupresores/uso terapéutico , Hígado/patología , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Recurrencia , Estudios Retrospectivos , Trasplante Homólogo
4.
J Viral Hepat ; 4(4): 235-42, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9278221

RESUMEN

Allograft infection in hepatitis B surface antigen (HBsAg)-positive patients undergoing liver transplant (OLT) is still significant, despite post-transplant prophylaxis with high doses of immunoglobulin to HBsAg. Baseline status and post-OLT levels of viraemia and wild-type and hepatitis B e antigen (HBeAg)-negative hepatitis B virus (HBV) were correlated with the clinical course of 16 consecutive HBsAg carriers. positive for hepatitis B e antibody, with hepatocellular carcinoma who underwent OLT and received permanent post-OLT prophylaxis with antibody to HBsAg (HBsAb). Fourteen patients had less than 10(3) HBV genome equivalents ml(-1) (eq ml[-1]) at baseline and remained HBV free after a median of 36 months following OLT. Two patients with mean pre-OLT viraemia higher than 10(5) genome eq ml(-1) and prevalent HBeAg-negative HBV viraemia before OLT suffered a severe graft hepatitis. Interferon-alpha2b (3 MU m(-2) per day) was able to reduce viraemia in both patients and to revert the clinical course of the infection in one, who remained infection-free 22 months after IFN treatment. Fourteen patients had less than 10(3) HBV genome eq ml(-1) at baseline and remained HBV free, after a median of 36 months following OLT, with permanent HBsAb immunoprophylaxis. These observations suggest that the quantitative analysis of HBV pre-OLT viraemia levels may provide a very useful tool for predicting the ideal time of liver replacement. Clinical trials on the use of antiviral drugs capable of inhibiting HBV serum levels before liver transplantation should be pursued on this premise.


Asunto(s)
Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B/virología , Trasplante de Hígado , Anciano , Carcinoma Hepatocelular/cirugía , Portador Sano , ADN Viral/sangre , Femenino , Hepatitis B/tratamiento farmacológico , Hepatitis B/inmunología , Hepatitis B/prevención & control , Anticuerpos contra la Hepatitis B/administración & dosificación , Anticuerpos contra la Hepatitis B/sangre , Antígenos de la Hepatitis B/análisis , Virus de la Hepatitis B/inmunología , Humanos , Inmunización Pasiva , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Hígado/virología , Cirrosis Hepática/cirugía , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Proyectos Piloto , Proteínas Recombinantes , Viremia
6.
Liver Transpl Surg ; 3(1): 46-53, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9377758

RESUMEN

Two case reports of hepatic angiomyolipoma, both originating in the caudate lobe, are reported with a review of the literature. The liver is the second most common site of angiomyolipoma, an uncommon benign tumor of mixed mesenchymal origin. It is commonly diagnosed following abdominal pain or as an asymptomatic mass discovered on abdominal ultrasound or computed tomography scan. Of 74 cases reported, the lesions ranged from 0.3 to 36 cm in diameter and are noted between the first and eighth decade, with predominant female predilection. The right lobe is the most common site, with lesions arising in the caudate lobe comprising only five cases. The natural history of the hepatic lesion is unknown. Malignant invasion or metastatic disease has not been documented. Hepatic and renal angiomyolipoma can occur concurrently (13 of 60 cases), although the majority are not biopsy proven. Multicentric hepatic disease occurs. The correlation between tuberous sclerosis and hepatic angiomyolipoma is not confirmed histologically and occurs rarely. These lesions have a characteristic radiographic appearance due to high fat content. Histologically, angiomyolipoma are characterized by an admixture of adipose tissue, blood vessels, and smooth muscle cells. These lesions cannot reliably be differentiated from a malignant lesion based on clinical history, radiologic examination, and/or pathologic interpretation. If clinical suspicion for malignancy is low, then careful observation with serial radiologic follow-up is performed. The treatment for a symptomatic or suspicious lesion is resection, if feasible. Liver transplantation may be considered for large or centrally located lesions not amenable to resection.


Asunto(s)
Angiomiolipoma/patología , Neoplasias Hepáticas/patología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad
7.
J Clin Pharmacol ; 37(12): 1121-8, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9506007

RESUMEN

Brequinar sodium (BQR), a substituted 4-quinoline carboxylic acid, was in clinical development in combination with cyclosporine (CsA) as a potentially effective therapy for the treatment and prophylaxis of rejection in organ transplant patients. This phase I study was performed in stable renal, hepatic, and cardiac transplant patients receiving CsA and prednisone maintenance therapy for immunosuppression. The pharmacokinetic objectives of this study were to characterize the pharmacokinetics of (a) single oral 0.5- to 4-mg/kg doses of BQR when given in combination with CsA and prednisone to stable renal, hepatic, and cardiac transplant patients and (b) steady-state oral doses of CsA, with and without single oral doses of BQR. In all three patient populations, the pharmacokinetics of BQR were characterized by a lower oral clearance (12-19 mL/min) than that seen in previous studies in patients with cancer (approximately 30 mL/min at similar doses) and a long terminal half life (13-18 hrs). This slower oral clearance for BQR could be due either to a drug interaction between BQR and CsA or to altered clearance or metabolic processes in patients with transplants. Steady-state CsA trough levels and the oral clearance of CsA were not affected by BQR coadministration. Among the three transplant populations, the cardiac transplant patients had lower oral clearance values of BQR and of CsA. The cause of this lower clearance is not known. Safety results indicate that BQR was well tolerated by this patient population.


Asunto(s)
Compuestos de Bifenilo/farmacocinética , Trasplante de Corazón/fisiología , Inmunosupresores/farmacocinética , Trasplante de Riñón/fisiología , Trasplante de Hígado/fisiología , Administración Oral , Adulto , Anciano , Compuestos de Bifenilo/sangre , Ciclosporina/sangre , Ciclosporina/farmacocinética , Femenino , Humanos , Inmunosupresores/sangre , Masculino , Persona de Mediana Edad
8.
Gen Hosp Psychiatry ; 18(6 Suppl): 20S-24S, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8937919

RESUMEN

Prior to the advent of the bioartificial liver there was little hope to offer the families of comatose patients unless an organ could be found immediately, or xenografting was attempted. The elevated intracranial pressure that develops is more life-threatening than prolonged bleeding times. Over a 2-year period, nine patients were bridged to transplantation using the BAL to keep them neurologically intact prior to surgery. The goal is to maintain the ICP less than 20 mmHg in adults and between 10 and 15 mmHg in children, so that the cerebral perfusion pressure remains above 50 mmHg. The first patients, a 35-year-old woman, arrived in stage II coma. The second patient, a 10-year-old boy in stage IV coma, had decerebrate posturing and anisocoria. The third patient, an 18-year-old girl, had an ICP of 28 mmHg with decerebrate posturing and disconjugate gaze. The fourth patient, a 34-year-old male, had an ICP of > 38 mmHg. The fifth patient, a 24-year-old male, had fixed dilated pupils. The sixth patient, a 50-year-old woman, had readings to 52 mmHg. The seventh patient, a 48-year-old male, had postoperative numbness in his fingertips that remitted. The eighth patient, a 31-year-old female, had decerebrate posturing and an ICP of 64 mmHg transiently. The ninth patient, a 52-year-old woman, had decerebrate posturing with a peak ICP of 50 mmHg. All nine patients survived.


Asunto(s)
Encefalopatía Hepática/terapia , Trasplante de Hígado/efectos adversos , Hígado Artificial/efectos adversos , Trastornos Mentales/etiología , Enfermedades del Sistema Nervioso/etiología , Listas de Espera , Adolescente , Adulto , Niño , Femenino , Estudios de Seguimiento , Humanos , Presión Intracraneal , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
9.
Hum Pathol ; 27(11): 1161-5, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8912825

RESUMEN

Polymerase chain reaction (PCR) has been used to study liver biopsy tissue in patients with known or suspected hepatitis C virus (HCV). Recent studies of cryptogenic cirrhosis using PCR have been based on study of sera, and HCV has not been shown. The failure to show HCV in patients so studied has left unanswered the question of whether or not patients with cryptogenic cirrhosis could still harbor the virus in the liver. The authors studied liver tissue, obtained at the time of orthopic liver transplantation from 10 patients clinically diagnosed as having end-stage liver disease without demonstrable origin, so-called cryptogenic cirrhosis, using reverse transcription (RT)-PCR to try to recover HCV-RNA. Formalin-fixed, paraffin-embedded tissue was used. For comparison, the authors also studied similarly obtained samples from 10 patients with typical hepatitis C-associated cirrhosis and 10 patients with end-stage liver disease resulting from autoimmune hepatitis. The authors recovered HCV-RNA from 9 of 10 livers from patients with cirrhosis resulting from HCV, and 3 of 10 livers from patients with autoimmune hepatitis. HCV-RNA was not recovered from any of the livers of the 10 patients designated as having cryptogenic cirrhosis.


Asunto(s)
Hepacivirus/aislamiento & purificación , Hepatitis C/virología , Cirrosis Hepática/virología , Hígado/virología , ARN Viral/análisis , Adolescente , Adulto , Anciano , Enfermedades Autoinmunes/patología , Enfermedades Autoinmunes/virología , Femenino , Hepatitis/patología , Hepatitis/virología , Hepatitis C/patología , Humanos , Hígado/patología , Hígado/cirugía , Cirrosis Hepática/patología , Cirrosis Hepática/cirugía , Trasplante de Hígado/patología , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos
10.
Liver Transpl Surg ; 2(3): 171-84, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-9346646

RESUMEN

Prostaglandins (PG) are involved in the regulation of many physiological processes in the liver and play a major role in the pathophysiology and treatment of liver diseases. In addition to their effects of cell growth and immune function, PGs have shown cytoprotective effects on hepatocytes in various toxic, ischemic, and infectious models of liver injury. Although the mechanisms for these beneficial effects have not been precisely delineated, synthetic PG analogues have increasingly been used in patients with acute liver failure and chronic liver disease. There is also increasing evidence suggesting that PGs may reduce the early morbidity and mortality associated with liver transplantation, particularly in the context of primary graft nonfunction and renal dysfunction associated with cyclosporine and tacrolimus therapy. PG analogues have also been used for the treatment and control of recurrent hepatitis B virus infection in liver allograft recipients. The purpose of this review is to evaluate the role of PGs in hepatic physiology and disease and to review the use of synthetic PG analogues in the clinical settings of liver failure and transplantation.


Asunto(s)
Citoprotección , Fallo Hepático/tratamiento farmacológico , Regeneración Hepática , Trasplante de Hígado , Prostaglandinas/fisiología , Animales , Humanos , Agregación Plaquetaria , Prostaglandinas/uso terapéutico , Vasodilatación , Replicación Viral
12.
Transplantation ; 60(12): 1497-503, 1995 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-8545881

RESUMEN

The rejection of cardiac xenografts in the hamster-to-rat combination is characterized by the production of IgM antibodies that result in the rapid loss of the graft. We have recently produced rat monoclonal antibodies (mAb) to hamster heart xenografts in an attempt to develop reagents for use in identifying the target antigens for this reaction and to study the nature of the genetic control of the humoral response. The monoclonals were created by the fusion of myeloma cells with splenic lymphocytes from LEW rat recipients of hamster cardiac xenografts. The hybridomas were screened for antibody production, reactivity to hamster cell surface antigens, and the ability to mediate hyperacute rejection of hamster heart xenografts. A panel of monoclonal antibodies has been identified that are capable of inducing hyperacute rejection. All of these mAbs are IgM and bind strongly to hamster vascular endothelium. None of the mAbs were lymphocytotoxic or bound to hamster lymphocytes or erythrocytes. Immunopathologic studies demonstrated that these mAbs react specifically with hamster vascular endothelium and mediate a complement-dependent humoral reaction leading to the destruction of the cardiac xenografts. One of the mAbs (designated as HAR-1) has been characterized in detail. HAR-1 detects antigens distributed in the vascular endothelium, epithelium of bronchi in the lung, small intestine, tubules of kidney, and selective components of lymphoid organs--e.g., the stromal cells of the spleen and thymic medullary epithelium. Western blot analysis of hamster heart proteins with HAR-1 showed multiple bands with two major bands migrating at 80 kDa and 48 kDa. Absorption of the HAR-1 antibody with 48 individual carbohydrate molecules demonstrated that the strongest reactivity of the antibody is with a sialyl-Lea carbohydrate antigen.


Asunto(s)
Rechazo de Injerto/inmunología , Trasplante de Corazón/inmunología , Trasplante Heterólogo/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Antígenos/análisis , Cricetinae , Endotelio Vascular/inmunología , Rechazo de Injerto/genética , Inmunoglobulina M/genética , Inmunoglobulina M/inmunología , Masculino , Mesocricetus , Ratas , Ratas Endogámicas Lew
13.
Liver Transpl Surg ; 1(6): 373-6, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9346615

RESUMEN

Orthotopic liver transplantation has been used to treat glycogen storage disease type IV. Most long-term surviving patients who have undergone liver transplantation have been free of neuromuscular and cardiac morbidity, and regression of cardiac amylopectin infiltration has been reported after liver transplantation. Leukocyte inclusions in glycogen storage disease type IV have also been reported. We present the case of a child who underwent orthotopic liver transplantation for glycogen storage disease type IV. In contrast to previous reports, at autopsy 2 1/2 years after transplantation, there was massive amylopectin deposits in his heart. Further, peripheral leukocytes never showed loss of amylopectin inclusions after transplantation. Orthotopic liver transplantation for type IV glycogen storage disease may not, in all cases, result in improvement in other affected organs. Consideration of multiorgan transplantation appears warranted.


Asunto(s)
Amilopectina/metabolismo , Enfermedad del Almacenamiento de Glucógeno Tipo IV/metabolismo , Cardiopatías/metabolismo , Trasplante de Hígado , Miocardio/metabolismo , Neutrófilos/patología , Biopsia , Resultado Fatal , Estudios de Seguimiento , Enfermedad del Almacenamiento de Glucógeno Tipo IV/patología , Enfermedad del Almacenamiento de Glucógeno Tipo IV/cirugía , Humanos , Lactante , Masculino , Miocardio/ultraestructura , Tomografía Computarizada por Rayos X
14.
Am Surg ; 61(10): 889-95, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7668463

RESUMEN

Although elderly patients are accounted for in all large series of major hepatic resections, the role of age as a determinant of outcome remains unclear. At Cedars-Sinai Medical Center, we review a series of 20 major hepatectomies for neoplasia performed in patients older than 66 years of age (4 of them > or = 80 years old) over a 5-year period. A retrospective comparison was conducted with a group of 22 hepatectomies for malignancy performed in 20 patients younger than 59 years of age during the same time period. The younger group had a significantly greater degree of liver resected (12 trisegmentectomies vs 3). Although one operative death (5% mortality) was observed in the elderly group, no statistically significant difference was noted, when compared to the younger group (Chi-square, P = 0.48). Likewise, no significant difference in the complication rate (20% vs 33%) was noticed (Chi-square, P = 0.8). Severe postoperative liver dysfunction was present in 2 cases (10%) in the elderly group and one (4%) in the younger group. These patients underwent a right trisegmentectomy (TS). Nine patients from each group were resected without red blood cell transfusion. We conclude that major hepatic resection in elderly patients without severe comorbid disease is a safe procedure that is not associated with an increased perioperative morbidity or mortality rate.


Asunto(s)
Hepatectomía , Neoplasias Hepáticas/cirugía , Complicaciones Posoperatorias/epidemiología , Factores de Edad , Anciano , Comorbilidad , Hepatectomía/mortalidad , Humanos , Neoplasias Hepáticas/epidemiología , Persona de Mediana Edad , Estudios Retrospectivos , Análisis de Supervivencia
15.
Liver Transpl Surg ; 1(3): 156-61, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-9346558

RESUMEN

We describe three patients referred for orthotopic liver transplantation with liver failure and portal hypertension who were found to have malignant vascular tumors: two patients with angiosarcoma and one patient with epithelioid hemangioendothelioma. Their clinical presentation mimicked decompensated chronic liver disease. None had tumor masses on computed tomography and ultrasonography. Massive tumor involvement of the liver was identified in the two patients studied by magnetic resonance imaging. Pathological examination of the explanted liver at the time of transplantation in one patient and autopsy in a second patient showed angiosarcoma. Laparoscopic liver biopsies in the third patient showed epithelioid hemangioendothelioma. The vascular origin of the tumor was established by histopathologic examination and confirmed with immunohistochemistry. Malignant vascular tumors of the liver should be included in the differential diagnosis of liver failure of unclear etiology.


Asunto(s)
Hipertensión Portal/etiología , Fallo Hepático/etiología , Neoplasias Hepáticas/complicaciones , Neoplasias de Tejido Vascular/complicaciones , Adulto , Biopsia , Diagnóstico Diferencial , Resultado Fatal , Hemangioendotelioma Epitelioide/complicaciones , Hemangioendotelioma Epitelioide/diagnóstico , Hemangiosarcoma/complicaciones , Hemangiosarcoma/diagnóstico , Humanos , Hipertensión Portal/diagnóstico , Hipertensión Portal/cirugía , Laparoscopía , Fallo Hepático/diagnóstico , Fallo Hepático/cirugía , Neoplasias Hepáticas/diagnóstico , Trasplante de Hígado , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Neoplasias de Tejido Vascular/diagnóstico , Tomografía Computarizada por Rayos X
16.
Liver Transpl Surg ; 1(2): 85-93, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9346546

RESUMEN

We have recently conducted a series of experiments to characterize the pattern of reaction of human natural antibodies (NA) with individual pig liver cells. Pooled normal human serum (PHS) was incubated with cultured pig hepatocytes (HEP), aortic endothelial cells (AEC), and portal endothelial cells (PEC), and the reaction of NA to different cell types was measured by antibody-mediated cytotoxic (MTT assay), antibody binding (ELISA), and flow cytometric analysis. The human NA displayed a differential pattern of binding with hepatocytes exhibiting a more limited expression of xenoantigen expression than either aortic or portal endothelial cells. These differences in reaction patterns were also noted for Western blot analysis of individual cell membrane extracts. Preincubation of the pig cells with anti-pig MHC antibodies did not inhibit the binding of human IgM natural antibodies to the pig cells. Comparison of the pattern of NA absorption following the use of bioartificial liver support in patients with acute hepatic failure demonstrated limited ability of pig hepatocytes to absorb substantial amounts of NA. These studies indicate that pig hepatocytes are less vulnerable to NA cytotoxicity than pig vascular endothelial cells and that pig vascular endothelial cells express xenoantigens that are unique and not found on hepatocytes.


Asunto(s)
Reacciones Antígeno-Anticuerpo/inmunología , Antígenos Heterófilos/inmunología , Endotelio Vascular/inmunología , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Hígado/inmunología , Animales , Anticuerpos Heterófilos/análisis , Anticuerpos Heterófilos/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Western Blotting , Citotoxicidad Inmunológica , Endotelio Vascular/citología , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Hígado/citología , Masculino , Porcinos
17.
Transplantation ; 59(3): 401-10, 1995 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-7871571

RESUMEN

We studied the rejection of cardiac allografts in a rat strain combination (PVG.R8 to PVG.1U) disparate for a single class I MHC antigen (RT1.Aa) to test the extent by which this molecule is recognized as peptides in association with recipient MHC molecules during graft rejection and the contribution of this recognition process to the rejection reaction. Three synthetic peptides that correspond to the portions of alpha-helices of the alpha 1 (P1, P2) and alpha 2 (P3) domains of the donor RT1.Aa molecule were used in this study. Splenocytes from heart allograft recipients at rejection responded in a proliferation assay to all 3 peptides and in a cytotoxic assay to peptides P1 and P2. The peptide-mediated proliferation and cytolytic reactions were blocked by antibodies against CD4/class II MHC and CD8 molecules. Serum from graft recipients at rejection contained significant titers of antibodies to peptides. Presensitization of graft recipients with the peptides resulted in a marked increase in peptide-mediated T cell and antibody responses. Although all 3 peptides were effective in eliciting active immune responses, the P3-mediated response was minimal when compared with those mediated by P1 and P2. Recipients presensitized with the peptides rejected their grafts in 5 days compared with 6 days for unsensitized animals. Recipients presensitized with donor-irradiated splenocytes and aortic endothelial cells, on the other hand, rejected their grafts in 1 and 3 days, respectively, which suggests that immunization with the whole RT1.Aa molecule is required to stimulate accelerated rejection of the graft. This rejection was associated with high titers of donor cell-specific antibodies that exhibited moderate cross-reactivity with the peptides. Our results clearly demonstrate that (1) the donor RT1.Aa molecule is recognized as peptides in the context of recipient class I and class II MHC molecules during the rejection of heart allografts, and (2) peptides derived from this molecule are highly immunogenic in that they contain epitopes recognized by CD4+ and CD8+ T cells and alloantibodies. Immune responses elicited by these peptides, however, did not significantly affect the rate of rejection. These results suggest that acute rejection of allografts may be mediated primarily by the direct recognition of intact MHC molecules.


Asunto(s)
Rechazo de Injerto/inmunología , Trasplante de Corazón/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Isoanticuerpos/biosíntesis , Secuencia de Aminoácidos , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Citotoxicidad Inmunológica , Endotelio Vascular/inmunología , Antígenos de Histocompatibilidad Clase I/química , Isoanticuerpos/sangre , Datos de Secuencia Molecular , Estructura Secundaria de Proteína , Proteínas/síntesis química , Proteínas/inmunología , Ratas , Ratas Endogámicas Lew , Bazo/inmunología , Trasplante Homólogo/inmunología
18.
Liver Transpl Surg ; 1(1): 16-22, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9346536

RESUMEN

Cytokines are thought to play an important role in the inflammatory and immune responses of allograft rejection. We evaluated the pattern of cytokine gene expression in 36 liver biopsy specimens obtained from 20 recipients of primary orthotopic liver allografts. Specific mRNA expression was identified by a polymerase chain reaction (PCR) using oligonucleotide primers specific for human interleukin (IL)-1 beta, IL-2, IL-4, IL-6, IL-10 Interferon (IFN) gamma, tumor necrosis factor (TNF)-alpha and beta-actin. We detected IL-1 beta, IL-6 and IFN-gamma cytokine message most consistently in patients with rejecting liver allografts. TNF-alpha and IL-2 were also observed in rejecting livers, but only during the early phases of the reaction. IL-4 was expressed in the majority of liver allograft biopsy specimens, regardless of the presence or absence of clinical or pathological evidence of rejection. Sequential biopsy specimens in rejecting allografts showed decreased cytokine expression after the induction of a positive response to immunosuppressive therapy. The analysis of biopsy specimens from stable liver grafts showed a predominance in the expression of IL-10. These results may reflect a differential production of inflammatory and regulatory cytokines in response to liver allograft rejection in transplant recipients. They suggest that three cytokines, IL-1 beta, IL-6 and IFN-gamma, may play an important role as markers for liver allograft rejection. Conversely, IL-10 expression was noted in patients with stable graft function. This pattern of expression may correlate with host immune responses that allow for prolonged, rejection-free survival of the graft.


Asunto(s)
Citocinas/metabolismo , Expresión Génica , Trasplante de Hígado , Hígado/metabolismo , Biomarcadores , Citocinas/genética , Cartilla de ADN/química , Femenino , Rechazo de Injerto/metabolismo , Rechazo de Injerto/prevención & control , Humanos , Inmunosupresores/uso terapéutico , Masculino , Reacción en Cadena de la Polimerasa , ARN/aislamiento & purificación , ARN Mensajero/biosíntesis , Estudios Retrospectivos , Sensibilidad y Especificidad , Trasplante Homólogo
19.
Am Surg ; 60(8): 620-4, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8030820

RESUMEN

Choledochal cyst is a rare congenital abnormality of the biliary tract characterized by dilatation and stasis. Cyst excision is now preferred to internal drainage because of the predilection for development of cancer in the unresected cyst wall. We report on four patients who required reoperations for complications of prior cystoenteric drainage from 14 to 21 years after the original operations. Gastrointestinal bleeding from cyst ulceration as occurred in one patient is heretofore unreported. This reoperative experience emphasizes the importance of cyst excision as primary therapy and underscores these principles: 1) The spectrum of complications, including infection, pancreatitis, cancer, and bleeding may occur with or without intracyst and ductal stones; 2) Radical operative procedures may be required for treatment of the complications; 3) Despite these, cholangiocarcinoma has a dismal prognosis; 4) Patients whose cysts remain unexcised require meticulous lifelong scrutiny and strong consideration for planned reoperation at the time of the first complication.


Asunto(s)
Quiste del Colédoco/cirugía , Coledocostomía/efectos adversos , Adulto , Anciano , Ampolla Hepatopancreática/patología , Enfermedades de los Conductos Biliares/etiología , Neoplasias de los Conductos Biliares/etiología , Conductos Biliares Intrahepáticos , Colangiocarcinoma/etiología , Colangitis/etiología , Colelitiasis/etiología , Quistes/etiología , Femenino , Estudios de Seguimiento , Hemorragia Gastrointestinal/etiología , Humanos , Persona de Mediana Edad , Reoperación
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