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1.
Am J Transplant ; 12(8): 2188-97, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22845911

RESUMEN

We sought to evaluate survival of liver transplant candidates living in geographic areas with limited access to specialized transplant centers (TxC). We analyzed survival outcome among candidates listed for liver transplant in United Network of Organ Sharing (UNOS) Region 4 from 2004 to 2010. Candidates were stratified into three groups according to the distance from the patient's residence to the closest hospital with a liver transplant program: Group 1 (Gr 1) <30 miles (m), Group 2 (Gr 2) 30-60 m and Group 3 (Gr 3) >60 m. Of the 5673 patients included in the study, 49% resided >30 m from a TxC. Eight percent of the cohort experienced death or dropped out of the list due to medical condition deterioration, with worse outcomes for Gr 2 and Gr 3 (8.5% and 9.9%, respectively, vs. 6.5% for Gr 1 [p < 0.001]). Among patients with a MELD score <20, mortality was higher in Gr 2 and Gr 3 compared to Gr 1 (p < 0.001). We conclude that for Region 4, the mortality risk in patients living >30 m from a TxC is higher. We suggest that the variable "distance from a TxC" should be used to improve the estimate of the mortality risk for patients on the waiting list.


Asunto(s)
Trasplante de Hígado/mortalidad , Femenino , Geografía , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos , Estados Unidos
2.
Transplant Proc ; 38(6): 1742-3, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908269

RESUMEN

BACKGROUND: The cellular and histological events that occur during the regeneration process in invertebrates have been studied in the field of visceral regeneration. We would like to explore the molecular aspects of the regeneration process in the small intestine. The aim of this study was to characterize the gene expression profiles of the intestinal graft to identify which genes may have a role in regeneration of graft tissue posttransplant. METHODS: In a patient undergoing living related small bowel transplantation (LRSBTx) in our institution, mucosal biopsies were obtained from the recipient intestine and donor graft at the time of transplant and at weeks 1, 2, 3, and 6 posttransplant. Total RNA was isolated from sample biopsies followed by gene expression profiles determined from the replicate samples (n = 3) for each biopsy using the Affymetrix U133 Plus 2.0 Human GeneChip set. RESULTS: Two profiles were obtained from the data. One profile showed rapid increase of 45 genes immediately after transplant by week 1 with significant changes (P < .05) greater than threefold including the chemokine CXC9 and glutathione-related stress factors, GPX2 and GSTA4. The second profile identified 133 genes that were significantly decreased by threefold or greater immediately after transplant week 1, including UCC1, the human homolog of the Ependymin gene. CONCLUSION: We have identified two gene expression profiles representing early graft responses to small bowel transplantation. These profiles will serve to identify and study those genes whose products may play a role in accelerating tissue regeneration following segmental LRSBTx.


Asunto(s)
Perfilación de la Expresión Génica , Mucosa Intestinal/patología , Intestino Delgado/trasplante , Donadores Vivos , Biopsia , Humanos , Proteínas Inmediatas-Precoces/genética , ARN/genética , ARN/aislamiento & purificación , Trasplante Homólogo/patología
3.
Transplant Proc ; 38(6): 1770-1, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908277

RESUMEN

Following small bowel transplantation (SBTx), approximating the midline abdominal fascia can be problematic in patients with severely retracted abdominal cavities. We first report the use of acellular dermal matrix (ADM) for abdominal closure following living related SBTx. A 44-year-old woman with ultra-short gut syndrome secondary to multiple bowel resections received a 160-cm segmental intestinal graft from her daughter. The graft ileocolic vessels were anastomosed end to side to the inferior vena cava and distal aorta. A terminal ileostomy was fashioned because the patient had previous panproctocolectomy. The graft perfused well, and the laparotomy was primarily closed. On postoperative day 1, the patient required surgical exploration for evacuation of hematoma. Due to graft edema in a significantly retracted abdominal cavity, a 12x7 cm fascia defect was evident. Leaving the abdomen open or using a mesh was not entertained as options due to the high risk of infections. Primary closure under tension would also jeopardize the transplant, increasing the risk of thrombosis. The fascia defect was closed using a segment of ADM. The patient did well and went home on the postoperative day 11. At 2-year follow-up she is well and on oral diet without fascia defect or incisional hernia. This is the first report of the use of ADM for abdominal closure in patients receiving a SBTx. ADM is considered safe when used in contaminated sites and can allow primary closure of difficult wounds often seen in SBTx patients.


Asunto(s)
Intestino Delgado/trasplante , Síndrome del Intestino Corto/cirugía , Poliposis Adenomatosa del Colon/complicaciones , Adulto , Anastomosis Quirúrgica , Colectomía , Femenino , Estudios de Seguimiento , Humanos , Íleon/cirugía , Nutrición Parenteral Total , Recto/cirugía , Síndrome del Intestino Corto/etiología , Resultado del Tratamiento
4.
Transplant Proc ; 38(6): 1738-9, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908267

RESUMEN

The purpose was to determine whether magnification endoscopy (ME) accurately diagnosed rejection in living related small bowel transplants (LRSBTx) during initial morphological adaptation of segmental intestinal grafts. The small bowel recipient was a 44-year-old woman with short gut syndrome following multiple bowel surgeries for familial adenomatous polyposis. ME was enhanced by chromoendoscopy staining. Bowel mucosa was washed with acetic acid and stained with methylene blue for optimal visualization of mucosal villi and to improve the diagnostic yield of biopsies. The recipient underwent surveillance ME with biopsy 16 times through the ileostomy in the first 9 months following transplantation. The recipient developed diarrhea in the postoperative course, which led to the suspicion of rejection. ME findings of patchy villus blunting were consistent with biopsy samples that showed mild acute cellular rejection. Episodes of rejection were treated with high-dose immunosuppressants and steroids. Reversal of rejection was monitored by follow-up ME, which showed increased length of villi and normalization of morphology. Biopsy confirmed these findings. The first endoscopy, at 5 days posttransplant, showed no evidence of intestinal ischemia. LRSBTx involves early morphological adaptation of the recipient small bowel mucosa, characterized by an increased length of villi. ME is a reliable technique to follow adaptation and detect early rejection. The superior imaging of small bowel mucosa created by ME chromoendoscopy enables early diagnosis and delivery of more prompt antirejection therapy to prevent progression of rejection. ME also confirmed that segmental LRSBTx caused minimal ischemic injury to the recipient.


Asunto(s)
Poliposis Adenomatosa del Colon/cirugía , Endoscopía del Sistema Digestivo/métodos , Rechazo de Injerto/diagnóstico , Intestino Delgado/trasplante , Adulto , Endoscopía/métodos , Femenino , Humanos , Reproducibilidad de los Resultados , Trasplante Homólogo/inmunología , Trasplante Homólogo/patología
5.
Transplant Proc ; 38(6): 1740-1, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908268

RESUMEN

BACKGROUND: Acute cellular rejection (ACR) is a common complication of small bowel transplantation (SBTx) and the major cause of graft loss. However, little is known regarding the genetic graft response to ACR in clinical transplants. In this study, we have determined a genetic expression profile of intestinal graft response to ACR after living related (LR) SBTx. RESULTS: By identifying the expression profiles of reported markers of rejection we were able to identify 57 genes that had significantly increased (more than twofold) expression in response to ACR. Known markers of rejection identified: MMP-9, MMP-2, VIP, IFNgamma, IL-2R, MADCAM-1, HSP-60, and HSP-70 all had greater than twofold increased expression after ACR diagnosed (week 3 to week 6). The newly identified genes were: IFI27, EPST11, APAF1, LAP3, STK6, and MDK. CONCLUSION: Newly identified up-regulated genes in response to ACR in small bowel graft are involved in the immune response, cell adhesion, neurogenesis, cell division and proliferation, DNA replication/repair, protein ubiquitin/proteolysis, and apoptosis. TNFalpha up-regulated early at week 2 biopsy may be an early genetic marker of ACR in SBTx.


Asunto(s)
Perfilación de la Expresión Génica , Rechazo de Injerto/genética , Intestino Delgado/trasplante , Biopsia , Marcadores Genéticos , Humanos , Intestino Delgado/patología , Periodo Posoperatorio , Trasplante Homólogo/inmunología , Trasplante Homólogo/patología
6.
Transplant Proc ; 38(6): 1849-50, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908302

RESUMEN

We tested the hypothesis that an anatomic scaffold placed in continuity with viable bowel might allow intestinal growth. Male ACI rats were used for the study. Acellular human dermis in the form of tubular scaffolds with an intraluminal diameter of approximately 0.3 cm was oriented with the luminal basement membrane and serosal dermal surface. The small bowel was transected approximately 2 cm distal to the ligament of Treitz. The graft was then anastomosed in continuity in group A (n = 5) or as a blind-ended pouch to a defunctionalized jejunal limb in group B (n = 8). The animals were sacrificed at various time points. Histology and immunohistochemistry were used to evaluate structural changes. Animals in group A developed peritonitis and were all sacrificed within the first week postoperatively. However, all animals in group B survived, increasing their body weight similarly to age-matched rats. Tissue samples obtained at sacrifice showed a progressively increasing amount of cellular infiltrate over time in the matrix. Epithelial regeneration, angioneogenesis, and myofibroblast infiltrate were seen at 2 weeks, while well-formed branching crypts were seen at 4 weeks. Intact mucosa extended across the anastomosis to the grafts at 6 months. This study demonstrated an anatomic scaffold of acellular matrix allowed mucosal regeneration from viable bowel placed in continuity. These findings set the basis for new intestinal elongation techniques.


Asunto(s)
Intestino Delgado/anatomía & histología , Intestino Delgado/trasplante , Regiones de Fijación a la Matriz/fisiología , Trasplante de Piel/métodos , Anastomosis Quirúrgica , Animales , Humanos , Masculino , Modelos Animales , Ratas , Ratas Endogámicas ACI , Trasplante Heterólogo
7.
Transplant Proc ; 37(1): 217-9, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15808599

RESUMEN

Islet transplantation success is limited by the posttransplant inflammatory response, and we are investigating the ability of antioxidants to neutralize this islet damage. We have shown that pyruvate can enhance the engraftment and functionality of a suboptimal islet mass in rats. The present study further investigated the effects of pyruvate, as well as the antioxidants vitamin E and vitamin C. In study A, 350 syngeneic islets were transplanted into the liver of chemically diabetic rats. Antioxidant treatment, or vehicle, was administered during the perioperative period and an intraperitoneal glucose tolerance test (IPGTT) was performed 2 months posttransplant. In study B, 500 syngeneic islets were transplanted under the kidney capsule of chemically diabetic rats. Antioxidant treatment was administered during the perioperative period. Islet-bearing kidney grafts were harvested 24, 48, and 96 hours posttransplant for histological study. Results revealed that pyruvate was the only significantly effective treatment in enhancing the engraftment and functionality of a suboptimal islet mass. Respectively, 56% and 80% of pyruvate-treated rats became normoglycemic after islet transplantation in study A and study B and had a normal insulin response to IPGTT. Histology results from the islet-bearing kidneys were inconclusive as to whether or not pyruvate has an antiapoptotic effect. We conclude that pyruvate, but not vitamin E or vitamin C, aids in the engraftment and functionality of a suboptimal islet mass with as much effectiveness as a full mass in this study. Further investigation into the mechanism of pyruvate protection is still warranted.


Asunto(s)
Antioxidantes/uso terapéutico , Ácido Ascórbico/uso terapéutico , Insulina/metabolismo , Trasplante de Islotes Pancreáticos/métodos , Vitamina E/uso terapéutico , Animales , Glucemia/metabolismo , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/cirugía , Prueba de Tolerancia a la Glucosa , Inflamación/prevención & control , Secreción de Insulina , Cuidados Intraoperatorios , Trasplante de Islotes Pancreáticos/fisiología , Ratas , Ratas Endogámicas Lew , Trasplante Isogénico
8.
Transplant Proc ; 37(1): 233-6, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15808605

RESUMEN

UNLABELLED: Islet transplantation offers a potential cure for type I diabetes, although its success has been limited, due to loss of cells by apoptosis stimulated by the procurement, ischemia, and the isolation process itself. RNA interference (RNAi) as mediated by short interfering RNAs (siRNAs) has become a potent tool to manipulate gene expression in mammalian cells. We describe the first successful introduction of siRNA directly into pancreatic islet cells both during in situ perfusion and from intravenous tail vein injection (in vivo). METHODS: siRNA was targeted to the pancreatic islets of BALB/c mice by retrograde portal vein perfusion or tail vein injection. Cy3-labeled siRNA was dissolved in University of Wisconsin (UW) solution at 2 microg/mL. After delivery pancreata were placed in cold storage at 4 degrees C in UW solution for 24 hours, followed by processing for immunofluorescent staining for insulin. Fluorescent imaging was obtained using a Nikon DIAPHOT 300 Inverted Micoscope with a Zeiss AxioCam and OpenLab image capturing software. RESULTS: In situ delivery of siRNA was demonstrated by fluorescent imaging composites of (red) siRNA in and along (green) insulin stained islets from pancreas sections as compared with untreated control sections. The siRNA was detected mainly in and along venous structures throughout the pancreatic tissue. In vivo delivery of siRNA into islets was observed by fluorescent images taken of isolated islets in culture. CONCLUSIONS: We have described the successful delivery of siRNA to pancreatic islets via a novel in situ pancreas perfusion technique and in vivo delivery via tail vein injection.


Asunto(s)
Trasplante de Islotes Pancreáticos/fisiología , Islotes Pancreáticos/fisiología , ARN Interferente Pequeño/metabolismo , Adenosina , Alopurinol , Animales , Secuencia de Bases , Glutatión , Inyecciones Intravenosas , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/citología , Ratones , Ratones Endogámicos BALB C , Microscopía Fluorescente , Soluciones Preservantes de Órganos , ARN Interferente Pequeño/administración & dosificación , Rafinosa
10.
Transplantation ; 60(11): 1366-70, 1995 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-8525540

RESUMEN

Liver-derived dendritic cell (DC) progenitors propagated in liquid culture in granulocyte/macrophage colony-stimulating factor exhibit low levels both of cell surface MHC class II antigens and of counter-receptors for CTLA-4/CD28. They fail to stimulate allogeneic T cells in mixed leukocyte cultures. To evaluate their in vivo functional significance, we determined their influence on survival of pancreatic islet allografts. Cultured B10.BR (H2k;I-E+) mouse liver-derived DC progenitors were injected (2 x 10(6) i.v.) into streptozotocin-diabetic B10 (H2b; I-E-) recipients 7 days before transplantation of pancreatic islets (700 IEq/mouse) from the same donor strain. No immunosuppressive agents were administered. Mean islet allograft survival time was prolonged from 15.3 days (in animals pretreated with syngeneic cells) to 30.3 days (P < 0.001) in mice pretreated with the donor-derived liver cells. In 20% of these animals, islet allograft survival exceeded 60 days. These data suggest that liver-derived DC progenitors may contribute both to the inherent tolerogenicity of the mouse liver and to its capacity to protect other allografts of the same donor strain from rejection.


Asunto(s)
Células Dendríticas/inmunología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Trasplante de Islotes Pancreáticos/inmunología , Animales , Supervivencia de Injerto , Tolerancia Inmunológica , Inmunofenotipificación , Hígado/citología , Hígado/inmunología , Activación de Linfocitos , Masculino , Ratones , Ratones Endogámicos C57BL , Bazo/inmunología
11.
Transplantation ; 72(1): 27-30, 2001 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-11468530

RESUMEN

BACKGROUND: Ischemia/reperfusion (I/R) injury is a limiting factor in liver transplantation. We have recently shown that pyruvate (PY) inhibits intestinal and renal I/R injury. This study aims to evaluate the protective effect of PY on hepatic I/R injury. METHODS: ACI rats were treated with PY, whereas control animals received placebo. Rats were killed after 60 min of partial hepatic ischemia and after 2, 6, 24, and 48 hr of reperfusion. For each time point, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase were measured, and liver biopsy specimens were obtained to evaluate morphology, DNA fragmentation, and apoptosis (terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling). RESULTS: The survival rate 48 hr after I/R was 83% in the control group, and 100% in the PY-treated group (P>0.05). Increased enzymatic levels and histologic findings showed increased liver damage in the untreated group compared with PY. In control rats, apoptosis was enhanced after 1 hr of ischemia and peaked after 2 hr of reperfusion, to decrease gradually 48 hr after reperfusion; in the PY group apoptosis was delayed and reduced. After 1 hr of ischemia, the number of apoptotic nuclei was significantly increased in control livers compared with normal preischemic livers, whereas the number was significantly reduced by PY. After 2 hr of reperfusion, the maximum number of apoptotic cells was observed, whereas PY significantly reduced the amount of apoptotic cells (P<0.05). Apoptosis was delayed in PY-treated livers to 6 hr after reperfusion, peaking at a significantly lower count compared with placebo-treated controls (P<0.05). CONCLUSION: These data indicate that PY has a protective effect on I/R injury of the liver.


Asunto(s)
Isquemia/prevención & control , Circulación Hepática/efectos de los fármacos , Ácido Pirúvico/farmacología , Daño por Reperfusión/prevención & control , Animales , Apoptosis/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/enzimología , Hígado/patología , Masculino , Ratas , Ratas Endogámicas ACI , Análisis de Supervivencia , Factores de Tiempo
12.
Transplantation ; 71(9): 1210-3, 2001 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11397951

RESUMEN

BACKGROUND: The majority of liver transplant centers require a 6-month abstinence period before listing candidates for liver transplantation with alcoholic cirrhosis and a persistent sobriety thereafter. We attempted to identify risk factors for failure to comply with these requirements. METHODS: Ninety-nine consecutive patients with alcoholic cirrhosis were referred for liver transplant evaluation between September 1996 and May 1998. The mean age was 49 years, 74% were male, and 54% were hepatitis C virus positive. To be listed, patients had to meet the following requirements. All patients received extensive psychosocial evaluations and were frequently monitored with random urine and blood alcohol tests; patients found positive were excluded or removed from the liver transplant waiting list. Detailed patient information was entered into a computerized database, and 36 discreet variables were analyzed in relation to success (patient listed and remained on the list) or failure (not listed or removed from the list based on noncompliance). RESULTS: Forty-nine patients were successfully listed. Nineteen received a transplant, with a 95% 1-year patient and graft survival rate and 21% alcohol relapse rate after transplantation. Twenty-two patients had either medical contraindication and/or died before transplant listing. Twenty-four patients were never listed and four were removed from the list due to recurrent alcoholism, for a total of 28 failures. Our statistical analysis identified five significant risk factors for failure: (I) living arrangement (alone/family versus community/friend), P=0.006; (II) history of suicide ideation, P=0.03; (III) history of previous alcohol-related hospitalization, P=0.01; (IV) lack of previous alcoholic rehabilitation before transplant evaluation, P=0.001; and (V) failure to accept further alcoholic rehabilitation before orthotopic liver transplantation, P=0.01. CONCLUSIONS: Our experience confirms that transplantation can be extremely successful in properly selected patients with alcoholic cirrhosis. We identified several predictive psychosocial factors of early alcoholic recidivism in transplant candidates.


Asunto(s)
Cirrosis Hepática Alcohólica/epidemiología , Trasplante de Hígado , Contraindicaciones , Femenino , Supervivencia de Injerto/fisiología , Humanos , Trasplante de Hígado/inmunología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Riesgo , Donantes de Tejidos/estadística & datos numéricos
13.
Surgery ; 127(2): 193-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10686985

RESUMEN

BACKGROUND: Hepatocyte transplantation is an attractive potential treatment for liver-based inborn errors of metabolism and for fulminant hepatic failure. Dalmatian dogs have a metabolic error that results in hyperuricosuria. This report focuses on the effect of multiple, sequential intrasplenic transplants of fresh and cryopreserved hepatocytes in dalmatians. METHODS: Dalmatians underwent intrasplenic hepatocyte transplantation with hepatocytes taken from healthy mongrels. Dalmatian urinary uric acid excretion was measured preoperatively, and this served as the control value. Three hepatocyte transplantations were performed at 30-day intervals--the first with freshly isolated cells, and both the second and the third with cryopreserved hepatocytes from the same donor. Urinary uric acid excretion was measured postoperatively twice per week. RESULTS: The urinary uric acid excretion decreased an average of 54% after the first hepatocyte transplantation. The effect was transient and lasted an average of 22 days (range, 19-50 days). Subsequent intrasplenic hepatocyte transplantation with cryopreserved hepatocytes resulted in similar decreases in urinary uric acid excretion. Each transplant resulted in a significant decrease in urinary uric acid excretion when compared with baseline values (P = < .001). CONCLUSIONS: Sequential intrasplenic hepatocyte transplantation is feasible in this model. This method provided a significant, but transient, correction in urinary uric acid excretion that was similar with either fresh or cryopreserved hepatocytes. A substantial biologic effect provided by cryopreserved hepatocytes has important implications in clinical hepatocyte transplantation.


Asunto(s)
Trasplante de Células , Hígado/citología , Trasplante Heterotópico , Animales , Supervivencia Celular , Criopreservación , Perros , Hepatopatías/cirugía , Errores Innatos del Metabolismo/cirugía , Errores Innatos del Metabolismo/orina , Bazo , Ácido Úrico/orina
14.
Cell Transplant ; 5(1): 53-5, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8665077

RESUMEN

We have tested the effect of donor bone marrow cell (DBMC) infusion on the survival of pancreatic islet allografts in the rat, without the use of cytoablative recipient conditioning. Lewis and diabetic Brown Norway rats were used as donors and recipients, respectively. Donor islets were placed beneath the left renal capsule. Infusion of DBMC and temporary immunosuppression followed by delayed islet transplantation resulted in indefinite survival of all islet grafts (MST > 180 days). Control animals demonstrated recurrent hyperglycemia (islet allografts rejection). Donor bone marrow derived cells were detected in the spleen and cervical lymph nodes of BN recipients of LEW bone marrow but not in the recipients of islet transplants alone. Second set full thickness skin grafts were performed in normal BN and in recipients of a previously successful ITX. Donor specific skin grafts were accepted in the animals that had received DBMC 40 days before the islet allograft, while animals receiving DBMC at the time of the islet allograft rejected the donor specific skin graft similarly to the controls. However, these animals did not reject a second set donor-specific islet transplant. The results indicate that radiation conditioning of the recipients was not necessary to induce microchimerism and graft acceptance in this rodent model of islet allotransplantation.


Asunto(s)
Trasplante de Médula Ósea/inmunología , Diabetes Mellitus Experimental/cirugía , Supervivencia de Injerto/inmunología , Terapia de Inmunosupresión/métodos , Trasplante de Islotes Pancreáticos/inmunología , Animales , Células de la Médula Ósea , Trasplante de Médula Ósea/métodos , Rechazo de Injerto/inmunología , Ratas , Ratas Endogámicas BN , Ratas Endogámicas Lew , Trasplante de Piel/inmunología , Factores de Tiempo , Trasplante Homólogo
15.
J Gastrointest Surg ; 5(2): 168-72; discussion 173, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11331480

RESUMEN

The advent of small bowel transplantation has provided selected patients with chronic intestinal irreversible failure with a physiologic alternative to total parenteral nutrition. Recently a standardized technique for living related small bowel transplantation (LR-SBTx) has been developed. Three patients with short bowel syndrome underwent LR-SBTx at our institution. All donors were ABO compatible with a good human leukocyte antigen match. A segment of 180 to 200 cm of ileum was harvested and transplanted with its vascular pedicle constituted by the ileocolic artery and vein. The grafts were transplanted with a short cold and warm ischemia time. The immunosuppression regimen consisted of oral FK-506, prednisone, and intravenous induction with atgam. Serial biopsies of the intestinal grafts were performed to evaluate rejection or viral infections. The postoperative course was uneventful for all donors. All of the recipients are currently alive and well. Two of three patients are off total parenteral nutrition and tolerating an oral diet with no limitations on daily activity. In the third patient, the graft was removed 6 weeks after transplantation. At the time of enterectomy, no technical or immunologic complications were documented. Absorption tests for D-xylose and fecal fat studies were performed showing functional adaptation of the segmental graft. All biopsies were negative for acute rejection. A well-matched segmental ileal graft from a living donor can provide complete rehabilitation for patients with short bowel syndrome. Our initial experience suggests that the risk of acute rejection and infection is greatly reduced compared to cadaveric bowel transplantation. Further clinical application of this procedure is warranted.


Asunto(s)
Íleon/trasplante , Donadores Vivos , Síndrome del Intestino Corto/cirugía , Adulto , Femenino , Rechazo de Injerto , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Nutrición Parenteral Total
16.
J Gastrointest Surg ; 3(5): 549-54, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10482714

RESUMEN

Pyruvate has been shown to prevent intestinal mucosal injury after ischemia-reperfusion. The aim of the present study was to determine whether pyruvate can (1) prevent postreperfusion mucosal injury occurring after intestinal preservation and subsequent transplantation and (2) exert a protective effect on the intestinal graft mucosa during acute rejection. Preservation mucosal injury was evaluated, after 2 hours of reperfusion, by comparing grafts transplanted in a rat syngeneic combination (ACI to ACI) after 2 hours of cold preservation using pyruvate (n = 6) or placebo (n = 6). Mucosal parameters obtained during acute rejection (allogeneic combination: ACI to Lewis) were compared between placebo-treated (n = 6) and pyruvate-treated (n &equals 6) animals. Tissue injury was evaluated by histopathologic examination, oxygen free radical production by luminol-enhanced chemiluminescence, and degree of neutrophil infiltration by myeloperoxidase staining. After reperfusion of the preserved grafts and during acute rejection, mucosal oxygen free radical levels and the number of infiltrating neutrophils were significantly (P <0.05) increased in the untreated grafts, whereas there was a statistically significant inhibition of these parameters in those treated with pyruvate. Mucosal injury, seen after reperfusion of the preserved grafts, was prevented by pyruvate. The histopathologic abnormalities observed in the untreated grafts during rejection were also significantly reduced by pyruvate. Treatment with pyruvate before cold preservation of intestinal grafts, in this rat model, reduced reperfusion mucosal injury, neutrophil infiltration, and oxygen free radical production. Oxygen free radicals were produced in the mucosa of the graft during acute rejection and their production was reduced by pyruvate, which exerted a protective effect on the rejecting allograft mucosa.


Asunto(s)
Rechazo de Injerto/prevención & control , Intestinos/trasplante , Ácido Pirúvico/uso terapéutico , Daño por Reperfusión/prevención & control , Enfermedad Aguda , Animales , Radicales Libres/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/patología , Masculino , Preservación de Órganos , Ratas , Ratas Endogámicas ACI , Ratas Endogámicas Lew , Especies Reactivas de Oxígeno/metabolismo
17.
Int Surg ; 84(4): 305-12, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10667809

RESUMEN

Pancreatic transplantation recently became a routine treatment for Type I diabetic patients with uremia or for those who previously received a kidney transplant with 1 year graft and patient survival of over 80% and 90%, respectively. Despite the life-long need for immunosuppression, this is clearly acceptable when compared to the need for dialysis and insulin therapy, and it reduces the evolution of diabetic complications. Isolated pancreatic transplant is less commonly applied because of the need for immunosuppression and the high rate of complications. However, this can still be an acceptable option for individual patients with brittle diabetes and hypoglycemic unawareness. Despite the fact that pancreas transplantation is an effective treatment for selected Type I diabetics, it remains a difficult surgical procedure with many potential complications and with several issues still subject to debate. In this article, the authors describe the procedure in all of its aspects and variations, and offer, through a review of the recent literature, insights on the current status of this transplant


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Trasplante de Páncreas , Nefropatías Diabéticas/cirugía , Rechazo de Injerto/prevención & control , Humanos , Terapia de Inmunosupresión , Trasplante de Riñón , Trasplante de Páncreas/inmunología , Selección de Paciente , Obtención de Tejidos y Órganos
18.
G Chir ; 21(4): 196-204, 2000 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-10812777

RESUMEN

Infections, sepsis and multiple organ failure syndrome are associated with high morbidity and mortality in human and experimental small bowel transplantation (SBTx). These complications are attributed to bacterial translocation demonstrated in animal and human studies. Bacterial translocation (BT) is defined as the passage of viable bacteria from the intestinal lumen to other tissues or organs. BT has been associated with different clinical and experimental situations, hemorrhagic shock, trauma, bowel obstruction, immunodepression, total parenteral nutrition, antibiotics. Although BT has been investigated in several small and large animal models of SBTx, precise information on the mechanisms involved are not available. It is possible that the operative procedure by itself may promote BT for the interaction of a number of factors such as preservation, ischemia/reperfusion, abnormal motility, lymphatic disruption and aberrant systemic venous drainage, acute or chronic rejection and antibiotic therapy. Furthermore, the potent immunosuppressive therapy used in these patients may augment the deleterious effects caused by BT. In this review we examined the existing literature concerning BT with particular regard to intestinal transplantation, to better understand the alterations in the symbiotic relationship between immunocompromised host and his gut microflora after SBTx.


Asunto(s)
Traslocación Bacteriana , Intestino Delgado/trasplante , Animales , Infecciones Bacterianas/etiología , Infecciones Bacterianas/microbiología , Humanos , Mucosa Intestinal/microbiología , Intestino Delgado/microbiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/microbiología , Conservación de Tejido/métodos
19.
G Chir ; 20(10): 440-4, 1999 Oct.
Artículo en Italiano | MEDLINE | ID: mdl-10555416

RESUMEN

The passage of viable bacteria through epithelial mucosa into lamina propria and then to mesentheric lymphnodes, and possibly other tissues was defined bacterial translocation (BT) by Berg and Garlington. The transepithelial passage of bacteria out of the intestinal lumen seems to occur in a variety of surgical conditions, and it is suspected to be involved in systemic inflammatory response syndrome, sepsis and multiorgan failure. There is increasing evidence that many nosocomial infections are caused by enteric translocating microorganisms, although the exact incidence of BT in humans is difficult to establish. Consensus is emerging that the barrier function of the gut is relevant in established critical illness and in patients at risk of developing sepsis and clinical studies have provided strong evidence that systemic infections often originate from intestinal flora in high risk patients. So the suspect of BT is made when there is infection after trauma, burns, major surgery, chemotherapy and immuno suppression. Bacterial translocation is also associated with organ transplantation, especially with small bowel transplantation. The Authors have summarized published experimental and clinical studies that have tried to understand the occurrence, mechanisms and effects of this complex process. At the present time there is a near full understanding of the relevance of BT like an interplay of diverse factors in a physiologically, immunologically and microbiologically complex intestinal tract. However additional experimental and clinical studies are needed to clarify the relationship between these phenomena and the development of sepsis or multiple organ dysfunction syndrome.


Asunto(s)
Infecciones Bacterianas/cirugía , Traslocación Bacteriana , Humanos , Recién Nacido
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