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1.
Transplant Proc ; 40(8): 2815-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929868

RESUMO

UNLABELLED: Even with substantial progress in the management of patients with glycogen storage disease type Ia (GSD-Ia), hepatic and renal complications may still develop during long-term follow-up. Herein, we report a case of preemptive living donor liver transplantation in a patient with GSD-Ia. PATIENT: The patient was a 5-year-old boy in whom GSD-Ia was diagnosed at age 10 months. Clinical symptoms included frequent hypoglycemic episodes, hyperlipidemia, hyperuricemia, and growth retardation, which were poorly controlled using conventional treatments. At age 5 years, frequent massive nasal bleeds developed, which led to severe anemia. The patient was brought to our institute for living donor liver transplantation (LDLT). Because GSD-Ia usually responds to dietary and medical treatments, we had a long discussion to determine whether preemptive LDLT was indicated. Transplantation was performed using the left lateral liver segment from the patients mother. The weight of his native liver was almost 2 kg. After reperfusion of the graft, the blood glucose concentration rapidly increased, and regular glucose was administered throughout the operation. The posttransplantation course was uneventful. The patient had no episodes of hypoglycemia with a regular diet. Total cholesterol, triglyceride, and uric acid concentrations also reverted to normal without medication. The patient had a few episodes of nasal bleeding after transplantation, which stopped spontaneously. He was discharged from our hospital with normal liver function. CONCLUSION: Patients with GSD-Ia should be considered for preemptive LDLT to improve their quality of life when clinical symptoms do not respond to appropriate treatment.


Assuntos
Doença de Depósito de Glicogênio Tipo I/cirurgia , Transplante de Fígado , Doadores Vivos , Glicemia/metabolismo , Pré-Escolar , Nutrição Enteral , Feminino , Hepatectomia/métodos , Humanos , Transplante de Fígado/fisiologia , Masculino , Coleta de Tecidos e Órgãos/métodos , Resultado do Tratamento
2.
Transplant Proc ; 40(7): 2118-20, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18790169

RESUMO

In coping with the shortage of deceased kidney donors, living donor kidney transplantation is mainly performed in Japan. We started our living unrelated spousal kidney transplantation program in 1989. In this analysis, we compared the results of 64 spousal transplantations performed between September 1989 and May 2007 with those of living related and deceased donor grafts. Despite the older age of the recipients and the lower HLA matching, the graft survival rates of spousal transplants were as good as those from living related donors and better than those from deceased donors, (P < .01). The graft survival rate of spousal kidney transplantation is improving with advances in immunosuppression, so spouses are considered important donors in Japan, which lacks deceased donors.


Assuntos
Transplante de Rim/imunologia , Doadores Vivos/estatística & dados numéricos , Nefrectomia/estatística & dados numéricos , Cônjuges , Coleta de Tecidos e Órgãos/estatística & dados numéricos , Cadáver , Feminino , Sobrevivência de Enxerto/fisiologia , Antígenos HLA/imunologia , Teste de Histocompatibilidade , Humanos , Imunossupressores/uso terapêutico , Japão , Masculino , Doadores de Tecidos/estatística & dados numéricos , Resultado do Tratamento
3.
Transplant Proc ; 40(7): 2297-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18790217

RESUMO

Patients surviving more than 10 years on hemodialysis (HD) are at risk of developing serious morbidity from unrelated conditions and from the many complications of long-term dialysis, such as cardiovascular disease, cerebrovascular disease, malignant tumors ectopic vascular calcification, diabetes mellitus, and disuse atrophy of the bladder. Long-term dialysis affects transplant patient outcomes and long-term graft survival. We analyzed 436 patients who underwent kidney transplantations between January 1987 and December 2007 to determine the impact of long-term dialysis on kidney transplant outcomes. The 39 patients who had been treated pretransplantation with dialysis for more than 10 years had an average length of dialysis treatment of 15.8 years (range, 10.0-32.5 years); they were denoted as the long-term hemodialysis group. The remaining 397 recipients showed an average of 3.7 years period of end-stage renal disease (ESRD) (range, 0-9.8, years; short-term hemodialysis group). There were significant differences in patient survival rates between the 2 groups: 93.2% vs 98.6%, at 1 year; 79.3% vs 95.4% at 5 years; and 58.4% vs 93.1% at 10 years (P = .0034). Also, graft survival was significantly different between the 2 groups: 89.2% vs 95.8% at 1 year; 60.4% vs 88.5% at 5 years; and 33.4% vs 80.4% at 10 years (P = .0026). Our results suggest that dialysis treatment for more than 10 years produces negative effects on post-transplantation patient and graft survival.


Assuntos
Sobrevivência de Enxerto/fisiologia , Transplante de Rim , Diálise Renal/efeitos adversos , Adulto , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Transplante de Rim/fisiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
4.
Transplant Proc ; 40(8): 2537-8, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18929793

RESUMO

Biliary complications are one of the most important problems in liver transplantation. Regardless of various improvements of surgical technique, liver transplantation is associated with significant biliary problems. In this article, we have described a biliary anastomosis method with a continuous suture (CS) technique in the posterior wall and interrupted suture (IS) technique for the anterior wall. We performed this biliary reconstruction in 28 adult patients between September 2003 and August 2007. Prior to that time our procedure was a CS anastomosis for both the anterior and posterior walls. A 5-Fr catheter is inserted into the biliary system. The current biliary complication was 3 cases (13.0%) of stenosis at the anastomosis, which is lower than that for a CS anastomosis. This anastomosis reduced biliary complications and is simple.


Assuntos
Anastomose Cirúrgica/métodos , Vesícula Biliar/cirurgia , Transplante de Fígado/efeitos adversos , Doadores Vivos , Complicações Pós-Operatórias/classificação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Transplant Proc ; 38(9): 2819-22, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17112838

RESUMO

INTRODUCTION: Focal segmental glomerulosclerosis (FSGS) has a tendency to recur frequently after kidney transplantation. We evaluated 12 cases to examine the incidence and long-term outcomes of recurrent FSGS. MATERIALS AND METHODS: Twelve patients with renal failure caused by FSGS received kidney allografts from living related donors. Tacrolimus or cyclosporine was used in combination with prednisolone and azathioprine or mycophenolate mofetil. RESULTS: The mean graft survival was 87.4 +/- 46.8 months. The graft survival rates in FSGS recipients were at 1 year, 100%; 5 years, 79.6%; 10 years, 68.2%. Two out of four recipients experienced graft loss due to chronic rejection. The other two out of four recipients with graft loss displayed severe proteinuria diagnosed as recurrence of FSGS. To treat recurrent FSGS, plasma exchange was partially effective to reduce proteinuria. CONCLUSION: Our incidence of recurrent FSGS is 16.7% with graft survivals at 5 and 10 years of 79.6% and 68.2%, respectively. The recurrence of FSGS happened after scheduled reductions in immunosuppressants. Careful observation is required with maintenance of immunosuppression in these patients.


Assuntos
Glomerulosclerose Segmentar e Focal/cirurgia , Transplante de Rim/fisiologia , Biópsia , Família , Feminino , Seguimentos , Glomerulosclerose Segmentar e Focal/patologia , Sobrevivência de Enxerto , Humanos , Doadores Vivos , Masculino , Transplante Homólogo , Resultado do Tratamento
6.
Transplant Proc ; 37(4): 1804-5, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15919472

RESUMO

INTRODUCTION: We reviewed ABO-incompatible living donor kidney transplantations (LDKT) performed in our institute. PATIENTS: Fourteen ABO-incompatible LDKT were carried out in the first era (September 1990-August 1996) and 13 were in the second era (October 2001-July 2004). All patients were treated with sessions of plasmapheresis before transplantation to reduce antibody titers <1:8. In the second era, those with rebound increase of antibody titers >1:64 after repeated plasmapheresis were not subjected to transplantation. Posttransplantation immunosuppression consisted of cyclosporin, predonisone, azathioprine, gusperimus hydrochloride (DSG), and antilymphocyte globulin (ALG) in the first era, and tacrolimus, mycophenolate mofetil, predonisone, and DSG in the second era. Splenectomy was performed during the transplantation. Anticoagulant therapy was introduced in the second era. RESULTS: One-, 2-, and 5-year graft survival in the first era was 57%, 57%, and 50%, respectively, values that were significantly lower than those of ABO-compatible cases in the same period (n = 101), namely, 1-, 3-, and 5-year graft survival rates 93%, 83%, and 76%, respectively. The main reason for graft and patient losses was infectious complications. In the second era, no recipient suffered a severe infectious complication and 1- and 2-year graft survival rates were both 100%. Four patients in the first era and 1 in the second era experienced a graft rejection episode between 10 days and 14 months after transplantation, but they were successfully treated with steroid pulse therapy. CONCLUSION: Although patients with high blood group antibody titers remain problematic, ABO-incompatible LDKT is an increasingly viable option for patients whose only donor is blood group-incompatible.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Incompatibilidade de Grupos Sanguíneos , Sobrevivência de Enxerto/imunologia , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Doadores Vivos , Quimioterapia Combinada , Sobrevivência de Enxerto/efeitos dos fármacos , Humanos , Plasmaferese , Cuidados Pré-Operatórios , Estudos Retrospectivos , Esplenectomia
7.
Transplant Proc ; 37(2): 859-60, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15848556

RESUMO

Immunosuppressive regimens including mycophenolate mofetil (MMF, Cellcept) were used in a renal transplant transplant program since May 2000 including 67 patients in whom it was the primary drug. Acute rejection (AR) occurred in 9 cases (13%) with 1-year graft survival rate of 96.8%. Pharmacokinetic (PK) studies of mycophenolic acid (MPA) were performed in 46 recent patients (total, 127 times). There was no correlation between dose (mg/kg) and blood concentration (AUC0-9: r2= 0.27). AUC0-9 was well correlated with AUC0-4 (r2= 0.91), but not with a single timepoint concentration. MPA AUC0-9 level was significantly higher among the AR-negative group (n = 33; 34.2 +/- 16.8 ng.hr/mL) compared with AR-positive group (n = 3; 28.2 +/- 1.9 ng.hr/mL; P = .04085) over the 2 weeks after transplantation. MPA AUC0-9 level was higher among the adverse event (AE-positive) group (n = 15; 39.2 +/- 22.8 ng.hr/mL) compared with the negative group (n = 21; 30.1 +/- 8.0 ng.hr/mL; P = .08772) within 2 weeks after transplantation. These results suggest the necessity of measuring AUC for therapeutic drug monitoring (TDM) of MMF-containing immunosuppressive therapy. The possible target level of MPA AUC0-9 would be approximately 30 ng.hr/mL using the present immunosuppressive regimen.


Assuntos
Imunossupressores/farmacocinética , Transplante de Rim/imunologia , Ácido Micofenólico/farmacocinética , Adolescente , Adulto , Cadáver , Criança , Ciclosporina/uso terapêutico , Monitoramento de Medicamentos/métodos , Rejeição de Enxerto/epidemiologia , Humanos , Imunossupressores/sangue , Imunossupressores/uso terapêutico , Transplante de Rim/mortalidade , Doadores Vivos , Pessoa de Meia-Idade , Ácido Micofenólico/sangue , Ácido Micofenólico/uso terapêutico , Análise de Sobrevida , Doadores de Tecidos
8.
Transplant Proc ; 37(2): 1049-51, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15848619

RESUMO

INTRODUCTION: The shortage of grafts in living kidney transplantation has forced the use of marginal grafts with arterial disease or grafts with multiple renal arteries (MRA). We reviewed the outcomes of transplants using allografts with MRA procured by open donor nephrectomy and report two cases requiring vascular reconstruction. PATIENTS AND METHODS: We reviewed 31 cases where renovascular reconstruction of an MRA graft was performed. A ex vivo pantaloon (side-to-side) anastomosis to create a common channel was performed in 24 cases including two cases of renal artery aneurysms in the grafts, where vascular reconstruction was performed in the same fashion after resection of the aneurysm. In four cases, an accessory artery was anastomosed sequentially after revasculization of the main artery. In three cases of grafts with multiple renal arteries, multiple anastomoses were done in situ after various ex vivo renovascular reconstructions. RESULTS: Twenty one MRA grafts including grafts with a renal aneurysm are functioning well for a mean follow-up 135 months. The graft survival rate was 71.0% at 5 years after transplantation and 67.7% at 10 years. The donors whose grafts had a renal aneurysm were also well and normotensive with normal renal function at present. Ten grafts failed mainly due to chronic allograft nephropathy. CONCLUSION: MRA grafts procured by open nephrectomy, including those with renal artery aneurysms, were engrafted successfully by applying appropriate renovascular surgery. The use of those grafts was safe for both the recipient and the donor.


Assuntos
Transplante de Rim/fisiologia , Doadores Vivos , Procedimentos de Cirurgia Plástica , Artéria Renal/cirurgia , Circulação Renal , Anastomose Cirúrgica , Aneurisma/cirurgia , Seguimentos , Humanos , Complicações Intraoperatórias/cirurgia , Transplante de Rim/métodos , Transplante de Rim/patologia , Artéria Renal/anormalidades , Artéria Renal/patologia , Estudos Retrospectivos , Fatores de Tempo
9.
Transplant Proc ; 37(2): 687-9, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15848502

RESUMO

AIM: Although better graft survival in patients treated with CsA has been obtained, chronic rejection continues to be a common complication in renal transplantation. In this study, we examined the graft survivals and complications among renal transplant patients followed for more than 25 years. METHODS: Between April 1970 and April 1979, 110 consecutive renal transplantations from living donors were performed in 110 patients. There were 83 men and 27 women of mean age of 27 +/- 7.0 years. A combination of azathioprine (AZ) and prednisolone (PSL) was used for the initial immunosuppressive therapy in all patients. RESULTS: Over 25 years postoperatively, 41 patients died with or without a functioning graft due to complications including infections and malignancies. Therefore, the 25-year patient survival was 62.5% and 34 patients returned to hemodialysis, yielding an actual 25-year graft survival of 36/110 (32.1%). The longest surviving graft is 30 years and 2 months. The main causes of death were infectious disease and malignancy; 73% of graft loss was due to chronic rejection. Mean serum creatinine of the patient with functioning grafts over 25 years is 1.2 mg/dL; 75% of patients displayed a value under 1.5 mg/dL. The mean dosage of Az was 52.3 mg/d and PSL was 5.6 mg/d.


Assuntos
Sobrevivência de Enxerto/fisiologia , Transplante de Rim/fisiologia , Doadores Vivos , Adulto , Azatioprina/uso terapêutico , Creatinina/sangue , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Transplante de Rim/mortalidade , Masculino , Estudos Retrospectivos , Análise de Sobrevida
10.
Transplantation ; 69(9): 1927-32, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10830233

RESUMO

BACKGROUND: Our laboratory has investigated the fabrication of a tissue-engineered intestine using biodegradable polymer scaffolds. Previously we reported that isolated intestinal epithelial organoid units on biodegradable polymer scaffolds formed cysts and the neointestine was successfully anastomosed to the native small bowel. The purpose of this study was to observe the development of tissue-engineered intestine after anastomosis and to demonstrate the effect of the anastomosis over a 9-month period. METHODS: Microporous biodegradable polymer tubes were created from polyglycolic acid. Intestinal epithelial organoid units were harvested from neonatal Lewis rats and seeded onto the polymers, which were implanted into the abdominal cavity of adult male Lewis rats followed by 75% small bowel resection (n=24). Three weeks after implantation, the unit/polymer constructs were anastomosed to the native jejunum in a side-to-side fashion. The anastomosed tissue-engineered intestine was measured by laparotomy 10, 24, and 36 weeks after the implantation (n= 14). During the laparotomy, all rats with an obstruction in their anastomosis were killed and excluded from the statistical analysis. Another five rats were also killed at 10 and 36 weeks for histological and morphometric studies. RESULTS: All analyzed rats survived this study and significantly increased their body weight by 36 weeks. Obstruction of the anastomosis was observed in one rat at 24 weeks and in two rats at 36 weeks; however, the anastomosis was patent in the other 11 rats by 36 weeks. The tissue-engineered intestine of these 11 rats increased in length and diameter at 10, 24, and 36 weeks after anastomosis; there were statistically significant differences between each time point except between the length of 10 and 24 weeks (P<0.016 by Wilcoxon signed rank test). Histologically the inner surface of the tissue-engineered intestine was lined with well-developed neomucosa at 10 and 36 weeks; however, there were small bare areas lacking neomucosa in the tissue-engineered intestine at 36 weeks. Morphometric analysis demonstrated no significant differences in villus number, villus height, and surface length of the neomucosa at 10 and 36 weeks. CONCLUSIONS: Anastomosis between tissue-engineered intestine and native small bowel resulted in no complications after operation and maintained a high patency rate for up to 36 weeks. The tissue-engineered intestine increased in size and was lined with well-developed neomucosa for the duration of the study.


Assuntos
Anastomose Cirúrgica , Intestino Delgado/cirurgia , Síndrome do Intestino Curto/cirurgia , Animais , Feminino , Seguimentos , Intestino Delgado/patologia , Masculino , Ácido Poliglicólico , Ratos , Ratos Endogâmicos Lew
11.
Transplantation ; 64(3): 405-10, 1997 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9275103

RESUMO

We investigated serotonin as a parameter of cold and warm ischemic injury prior to transplantation. Lewis rats were used as both donors and recipients, and the proximal 20 cm of jejunum served as the graft. The grafts were preserved in 4 degrees C lactated Ringer's solution for 0, 6, 12, 18, and 24 hr after harvest for cold ischemia (n=7/group). The superior mesenteric artery was clamped for 0, 15, 30, 60, and 120 min before harvest for warm ischemia (n=7/group). The serotonin concentration was measured in the luminal effluent and the preservation solution before transplantation, and total serotonin was calculated as the sum of these amounts. Finally, transplantation was performed heterotopically. Total serotonin increased significantly with both cold and warm ischemic time (P<0.01 by analysis of variance, Fisher's PLSD); however, between 18 hr and 24 hr of cold ischemic time only, there were no significant changes. Total serotonin levels correlated well with cold and warm ischemic time, as shown by linear regression analysis (cold ischemia: R2=80.2%, P<0.01; warm ischemia: R2=92.8%, P<0.01). We established the cutoff level of total serotonin to predict the graft survival at 2200 ng, and using this critical level, graft survival was predicted by total serotonin with a sensitivity of 71.4% and a specificity of 89.8%. Immunohistochemical staining with the serotonin antibody revealed that the number of serotonin-positive cells decreased with both cold and warm ischemic time. In conclusion, serotonin is a useful parameter of cold and warm ischemic injury before transplantation and can assist in predicting graft survival.


Assuntos
Intestino Delgado/transplante , Traumatismo por Reperfusão/prevenção & controle , Serotonina/uso terapêutico , Condicionamento Pré-Transplante , Animais , Temperatura Baixa , Sobrevivência de Enxerto/efeitos dos fármacos , Temperatura Alta , Imuno-Histoquímica , Intestino Delgado/irrigação sanguínea , Intestino Delgado/patologia , Masculino , Soluções para Preservação de Órgãos/química , Ratos , Ratos Endogâmicos Lew , Serotonina/análise
12.
Transplantation ; 67(2): 227-33, 1999 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-10075585

RESUMO

BACKGROUND: Our laboratory is investigating the tissue engineering of small intestine using intestinal epithelial organoid units seeded onto highly porous biodegradable polymer tubes. This study investigated methods of stimulation for optimizing neointestinal regeneration. METHODS: Intestinal epithelial organoid units harvested from neonatal Lewis rats were seeded onto porous biodegradable polymer tubes and implanted into the omentum of adult Lewis rats in the following groups: (1) the control group (group C), implantation alone (n=9); (2) the small bowel resection (SBr) group, after 75% SBr (n=9); (3) the portacaval shunt (PCS) group, after PCS (n=8); and (4) the partial hepatectomy (PH) group, after 75% PH (n=8). Neointestinal cyst size was recorded using ultrasonography. Constructs were harvested at 10 weeks and were examined using histology. Morphometric analysis of the neomucosa was obtained using a computer image analysis program (NIH Image, version 1.59). RESULTS: Cyst development was noted in all animals. Cyst lengths and diameters were significantly larger in the SBr group at 7 and 10 weeks compared with the other three groups (P<0.05; analysis of variance [ANOVA], Fisher's protected least significant difference). Histology revealed a well-vascularized tissue with a neomucosa lining the lumen with invaginations resembling crypt-villus structures. Morphometric analysis demonstrated a significantly greater villus number, height, area, and mucosal surface in the SBr group compared with the other three groups and a significantly greater crypt number and area in the PCS group compared with group C (P<0.05; ANOVA, Fisher's protected least significant difference). CONCLUSIONS: Intestinal epithelial organoid units transplanted on porous biodegradable polymer tubes can successfully vascularize, survive, and regenerate into complex tissue resembling small intestine. SBr and, to a lesser extent, PCS provide significant regenerative stimuli for the morphogenesis and differentiation of tissue-engineered small intestine.


Assuntos
Materiais Biocompatíveis , Mucosa Intestinal/fisiologia , Mucosa Intestinal/transplante , Intestino Delgado/fisiologia , Intestino Delgado/transplante , Organoides/fisiologia , Transplante Isogênico/fisiologia , Animais , Animais Recém-Nascidos , Peso Corporal , Cistos/diagnóstico por imagem , Cistos/patologia , Hepatectomia , Processamento de Imagem Assistida por Computador , Mucosa Intestinal/citologia , Masculino , Neovascularização Fisiológica , Organoides/ultraestrutura , Ácido Poliglicólico , Derivação Portocava Cirúrgica , Ratos , Ratos Endogâmicos Lew , Regeneração , Transdução de Sinais , Transplante Isogênico/métodos , Ultrassonografia
13.
Transplantation ; 67(2): 241-5, 1999 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-10075587

RESUMO

BACKGROUND: Previous work from this laboratory has shown that isolated intestinal epithelial organoid units on porous biodegradable polymer scaffolds formed vascularized cysts lined by a neomucosa. The purpose of this study was to demonstrate anastomosis between tissue-engineered intestine and the native small bowel and to observe the effect of this anastomosis on cyst growth. METHODS: Intestinal epithelial organoid units from neonatal Lewis rats were seeded onto porous biodegradable polymer tubes made of polyglycolic acid, and they were implanted into the omentum of adult male Lewis rats. Three weeks after implantation, the unit-polymer constructs were anastomosed in a side-to-side fashion to the native jejunum in 20 rats (group 1). The other 18 rats were closed without anastomosis (group 2). All 38 tissue-engineered constructs were harvested 10 weeks after implantation. Four rats underwent upper gastrointestinal (GI) study before they were killed. RESULTS: The rats in group 1 increased their body weights equal to those in group 2, and there was no statistically significant difference between the two groups. Upper GI examinations revealed no evidence of either bowel stenosis or obstruction at the anastomotic site. Grossly, the patency of the anastomosis was 90% and the lumen of the cyst was visualized by the upper GI study. At the second operation, there was no significant difference in the size of the cysts in either group: however, at the time the rats were killed, the length of the cysts in group 1 was significantly longer than that in group 2 (P<0.05 using Mann-Whitney U test). Histological examination showed that cysts after anastomosis were lined by a neomucosa in continuity to native small bowel across the anastomotic site and also demonstrated crypt-villus structures. Morphometric study demonstrated that cysts in group 1 had significantly greater villus number, height, and surface length than did those in group 2. CONCLUSIONS: Anastomosis between tissue-engineered intestine and native small bowel resulted in no complications after the operation, kept a high patency rate, and maintained mucosal continuity between the tissue-engineered intestine and native small bowel. Furthermore, anastomosis had a positive effect on cyst size and development of the mucosa in the tissue-engineered intestine.


Assuntos
Anastomose Cirúrgica/métodos , Biopolímeros , Mucosa Intestinal/cirurgia , Mucosa Intestinal/transplante , Intestino Delgado/cirurgia , Intestino Delgado/transplante , Transplante Isogênico/métodos , Animais , Animais Recém-Nascidos , Cistos , Feminino , Mucosa Intestinal/fisiologia , Intestino Delgado/fisiologia , Masculino , Organoides/ultraestrutura , Ácido Poliglicólico , Ratos , Ratos Endogâmicos Lew , Transplante Isogênico/patologia , Transplante Isogênico/fisiologia
14.
Transplantation ; 72(2): 291-5, 2001 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-11477355

RESUMO

BACKGROUND: A continuing shortage of cadaveric liver even for adult patients has motivated not a few centers to proceed to living-donor liver transplantation using right lobe grafts. One of controversies is potential congestion in the graft anterior segment by the deprivation of the middle hepatic vein. METHODS: Hepatic tissue oxygenation and hemoglobin concentration were investigated with a near-infrared spectroscopy in the course of harvesting and implantation in living-donor liver transplantation. Twenty adult recipients of right lobe graft were involved in the study. The aim of the analysis was to detect tissue congestion or ischemia. RESULTS: No significant change in mean hepatic tissue oxygenation and hemoglobin was noted in the right lobe during donor operation even after hepatic parenchymal transection, although some trend for relative congestion, i.e., increased tissue hemoglobin, compared with the left lobe was observed. After graft reperfusion in the recipient, both mean hepatic tissue oxygen saturation and hemoglobin decreased significantly in the anterior segment, which was accompanied by increased heterogeneity of tissue hemoglobin and oxygenation. Increased heterogeneity of oxygenation and decreased tissue hemoglobin were observed also in the posterior segment. CONCLUSIONS: The anterior segment in right lobe living-donor liver transplantation is sensitive to ischemia, rather than congestion, at least in the immediate phase after graft reperfusion. The anterior segment seems to be also more prone to circulatory disturbance than the other part of the graft.


Assuntos
Circulação Hepática/fisiologia , Transplante de Fígado/fisiologia , Microcirculação/fisiologia , Adulto , Pressão Sanguínea , Família , Feminino , Hemoglobinas/metabolismo , Hepatectomia/métodos , Humanos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Oxiemoglobinas/metabolismo , Espectrofotometria Infravermelho/métodos , Coleta de Tecidos e Órgãos/métodos
15.
Tissue Eng ; 6(1): 39-44, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10941199

RESUMO

Our laboratory has investigated hepatocyte transplantation using biodegradable polymer matrices as an alternative treatment to end-stage liver disease. One of the major limitations has been the insufficient survival of an adequate mass of transplanted cells. This study investigates a novel method of dynamic seeding and culture of hepatocytes in a flow perfusion system. In experiment I, hepatocytes were flow-seeded onto PGA scaffolds and cultured in a flow perfusion system for 24 h. Overall metabolic activity and distribution of cells were assessed by their ability to reduce MTT. DNA quantification was used to determine the number of cells attached. Culture medium was analyzed for albumin content. In Experiment II, hepatocyte/polymer constructs were cultured in a perfusion system for 2 and 7 days. The constructs were examined by SEM and histology. Culture medium was analyzed for albumin. In experiment I, an average of 4.4 X 10(6) cells attached to the scaffolds by DNA quantification. Cells maintained a high metabolic activity and secreted albumin at a rate of 13 pg/cell/day. In experiment II, SEM demonstrated successful attachment of hepatocytes on the scaffolds after 2 and 7 days. Cells appeared healthy on histology and maintained a high rate of albumin secretion through day 7. Hepatocytes can be dynamically seeded onto biodegradable polymers and survive with a high rate of albumin synthesis in the flow perfusion culture system.


Assuntos
Técnicas de Cultura de Células/métodos , Fígado/citologia , Albuminas/metabolismo , Animais , Materiais Biocompatíveis , Engenharia Biomédica , Sobrevivência Celular , Transplante de Células , Fígado/fisiologia , Transplante de Fígado , Microscopia Eletrônica de Varredura , Perfusão , Ácido Poliglicólico , Ratos
16.
Tissue Eng ; 6(2): 105-17, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10941206

RESUMO

To date, many approaches to engineering new tissue have emerged and they have all relied on vascularization from the host to provide permanent engraftment and mass transfer of oxygen and nutrients. Although this approach has been useful in many tissues, it has not been as successful in thick, complex tissues, particularly those comprising the large vital organs such as the liver, kidney, and heart. In this study, we report preliminary results using micromachining technologies on silicon and Pyrex surfaces to generate complete vascular systems that may be integrated with engineered tissue before implantation. Using standard photolithography techniques, trench patterns reminiscent of branched architecture of vascular and capillary networks were etched onto silicon and Pyrex surfaces to serve as templates. Hepatocytes and endothelial cells were cultured and subsequently lifted as single-cell monolayers from these two-dimensional molds. Both cell types were viable and proliferative on these surfaces. In addition, hepatocytes maintained albumin production. The lifted monolayers were then folded into compact three-dimensional tissues. Thus, with the use microfabrication technology in tissue engineering, it now seems feasible to consider lifting endothelial cells as branched vascular networks from two-dimensional templates that may ultimately be combined with layers of parenchymal tissue, such as hepatocytes, to form three-dimensional conformations of living vascularized tissue for implantation.


Assuntos
Órgãos Artificiais , Prótese Vascular , Fígado , Silício , Animais , Engenharia Biomédica , Divisão Celular , Células Cultivadas , Endotélio Vascular/citologia , Vidro , Fígado/irrigação sanguínea , Fígado/citologia , Transplante de Fígado , Masculino , Omento/cirurgia , Ratos , Ratos Endogâmicos Lew
17.
Tissue Eng ; 5(4): 339-46, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10477856

RESUMO

The purpose of this study was to demonstrate the feasibility of end-to-end anastomosis between tissue-engineered intestine and native small bowel and to investigate the effect of this anastomosis on their growth. Microporous biodegradable polymer tubes were created from a fiber mesh of polyglycolic acid sprayed with 5% polylactic acid. Intestinal epithelial organoid units were harvested from neonatal Lewis rats and seeded onto polymers. These constructs were implanted into the omentum of adult Lewis rats. Three weeks after the implantation, the constructs (n = 7) were anastomosed to the native jejunum in an end-to-end fashion. Ten weeks after implantation, the tissue-engineered intestine was harvested. Four of 7 rats survived for 10 weeks and the overall patency rate of the anastomosis was 78% (11 of 14 anastomosis). The maximal length of the tissue-engineered intestine at week 3 and 10 was 1.80 +/- 0.32 and 1.93 +/- 0.39 cm (mean +/- SD). Histologically, the tissue-engineered intestine was lined with a well-developed neomucosal layer that was continuous with the native intestine. We conclude that anastomosis between tissue-engineered intestine and native small bowel had a moderately high patency rate and had a positive effect on maintenance of the size of the neointestine and development of the neomucosa.


Assuntos
Anastomose Cirúrgica/métodos , Órgãos Artificiais , Mucosa Intestinal/citologia , Mucosa Intestinal/cirurgia , Intestino Delgado/cirurgia , Animais , Animais Recém-Nascidos , Materiais Biocompatíveis , Engenharia Biomédica , Transplante de Células , Feminino , Mucosa Intestinal/fisiologia , Ácido Láctico , Masculino , Omento , Poliésteres , Ácido Poliglicólico , Polímeros , Ratos , Ratos Endogâmicos Lew
18.
Arch Surg ; 134(11): 1184-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10555631

RESUMO

Great advances in the field of transplantation have been made in the last half of this century. However, the severe scarcity of donor organs, especially in the pediatric population, has become a major limitation. A new field, tissue engineering, applies the principles of biology and engineering toward the development of biological substitutes that restore, maintain, or improve tissue function. This article discusses the groundwork and challenges of this interdisciplinary field and its attempts to provide solutions to create new tissue for transplantation and other fields of reconstructive surgery.


Assuntos
Procedimentos de Cirurgia Plástica , Transplante , Órgãos Artificiais , Materiais Biocompatíveis , Engenharia Biomédica/tendências , Cartilagem/citologia , Transplante de Células , Previsões , Valvas Cardíacas/citologia , Humanos , Intestinos/citologia , Fígado/citologia , Procedimentos de Cirurgia Plástica/tendências , Transplante/tendências
19.
Life Sci ; 70(3): 325-36, 2001 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-12005265

RESUMO

We evaluated the time course of osteoinduction by an adenoviral vector, AxCAOBMP-2, in normal rats (Group I) and 2 immunosuppressed groups (Groups II and III). Immunosuppression was induced by 125 mg/kg of cyclophosphamide injected intraperitoneally the day before vector injection. Groups I and III received a high dose of AxCAOBMP-2 (25 microl; 8.75 x 10(8) pfu) and Group II a low dose (5 microl; 1.75 x 10(8) pfu). Each dose of AxCAOBMP-2 was injected into the right calf muscle of rats. On days 7, 14 and 21 postinjection, the osteoinducive activity in each group was investigated radiologically, histologically, immunohistochemically and biochemically. Osteoinduction was observed only in Groups II and III on days 14 and 21. The activity of osteoinduction in Group III was higher than that in Group II. There was little difference in the expression of LacZ between Groups I and III on day 3. However, there was a marked difference in BMP-2 protein expression between Groups I and III on day 7 postinjection. We speculated that the reason for this was that most of the infected cells were eliminated by the immune system of the host from days 3 to 7. These results suggest that gene therapy with AxCAOBMP-2 under transient immunosuppression may be useful for bone reconstruction.


Assuntos
Adenoviridae/genética , Proteínas Morfogenéticas Ósseas/genética , Terapia Genética , Osteogênese , Fator de Crescimento Transformador beta , Fosfatase Alcalina/metabolismo , Animais , Proteína Morfogenética Óssea 2 , Cálcio/análise , Ciclofosfamida/farmacologia , Vetores Genéticos , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar
20.
Transplant Proc ; 36(2 Suppl): 181S-185S, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15041333

RESUMO

The immunological barrier remains the major obstacle to the widespread use of transplantation as a replacement therapy for terminal organ failure. Since the first successful renal transplant performed by Hume et al in 1952, there has been an elusive search for agents rendering the immune mechanism unresponsive to the specific alloantigen stimulus of the engrafted organ while sparing nonspecific host resistance. Immunosuppressive therapies in organ transplantation can be divided into the following four main classes; chemical (pharmaceutical), biological (immunological), physical (radiological), and surgical. Of these, chemical agents (drugs) have continued to play a principal role. The discovery of new immunosuppressive drugs such as corticosteroids, azathioprine, cyclosporine (CsA), tacrolimus, mycophenolate mofetils and so on made an epoch at each stage in history of clinical organ transplantation. The recent immunosuppressants were designed to focus their action selectively on T and /or B cells by inhibiting cytokine synthesis (CsA, FK506), cytokine action (Rapamycin), or cell differentiation (15-deoxyspergualin) pathways rather than to act on immune systems in a nonselective fashion. CsA has improved the success of kidney transplantation, reducing the incidence and severity of acute rejection and improving the patient and graft survival. Sandimmun Neoral offers promise due to its better bioavailability and limited dependence on bile flow for absorption. Long-term studies are under way to determine its effectiveness and safety. Therapeutic drug monitoring and combination therapy with CsA are investigated also.


Assuntos
Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Ciclosporina/farmacocinética , Ciclosporina/toxicidade , Monitoramento de Medicamentos , Quimioterapia Combinada , Sobrevivência de Enxerto/imunologia , Humanos , Transplante de Rim/mortalidade , Transplante de Rim/patologia , Análise de Sobrevida
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