24 results on '"Tzakis AG"'
Search Results
2. Liver, pancreas and kidney transplantation for the treatment of Wolcott-Rallison syndrome.
- Author
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Tzakis AG, Nunnelley MJ, Tekin A, Buccini LD, Garcia J, Uchida K, Neville HL, Nares MA, Ruiz P, and Bodamer O
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- Child, Diabetes Mellitus, Type 1 complications, Diabetes Mellitus, Type 1 epidemiology, Epiphyses surgery, Female, Humans, Liver Failure, Acute epidemiology, Osteochondrodysplasias complications, Renal Insufficiency epidemiology, Risk Factors, Treatment Outcome, Diabetes Mellitus, Type 1 surgery, Epiphyses abnormalities, Kidney Transplantation, Liver Transplantation, Osteochondrodysplasias surgery, Pancreas Transplantation
- Abstract
We present the case of a child who underwent a combined liver, pancreas and double kidney transplant following complications of Wolcott-Rallison syndrome (WRS) a rare genetic disorder that causes infantile insulin-dependent diabetes mellitus (IDDM) and often death in childhood from fulminant liver and concomitant kidney failure. WRS is characterized clinically through infantile IDDM, propensity for liver failure following viral infections, bone dysplasia and growth failure and developmental delay. Fewer than 60 cases with WRS are reported in the literature, mostly from consanguineous parents. Future episodes of liver failure, the main contributor to the increased mortality in WRS, may be prevented through timely liver transplantation. To the best of our knowledge, transplantation has not been utilized to manage complications of WRS prior to this report., (© Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.)
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- 2015
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3. Citrulline level is a potent indicator of acute rejection in the long term following pediatric intestinal/multivisceral transplantation.
- Author
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Hibi T, Nishida S, Garcia J, Tryphonopoulos P, Tekin A, Selvaggi G, Weppler D, Levi DM, Ruiz P, and Tzakis AG
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- Biomarkers blood, Biopsy, Child, Child, Preschool, Cohort Studies, Female, Follow-Up Studies, Humans, Infant, Intestinal Mucosa metabolism, Intestines pathology, Longitudinal Studies, Male, Predictive Value of Tests, Prospective Studies, Retrospective Studies, Severity of Illness Index, Viscera metabolism, Viscera pathology, Citrulline blood, Graft Rejection blood, Graft Rejection diagnosis, Intestines transplantation, Organ Transplantation, Viscera transplantation
- Abstract
Citrulline has been advocated as a marker for acute cellular rejection (ACR) in intestinal transplantation; however, its significance as a forewarning in the long-term follow-up remains unknown. This study aimed to investigate the association between citrulline levels and the grading of ACR to establish a cutoff point that accurately predicts ACR beyond 3 months posttransplant in the pediatric patient population. During a 16-year period (1995-2011), a total of 13 499 citrulline samples were prospectively collected from 111 consecutive pediatric intestinal/multivisceral transplant recipients: 2155 were obtained concurrently with intestinal biopsies. There were 185 ACR episodes observed among 74/111 (67%) patients (median follow-up: 4.4 years). Citrulline levels were inversely proportional to the severity of ACR. Negative predictive values for any type of ACR (cutoff, 20 μmol/L) and moderate/severe ACR (cutoff, 10 μmol/L) were 95% and 99%, respectively. When patients were divided according to graft size, diagnostic accuracy using the same cutoff was identical. Similarly, subgroup analysis by the timing of citrulline measurement prior to biopsy varying from 1 to 7 days demonstrated comparable results. Citrulline is a potent indicator as a danger signal for ACR, being an exclusionary, noninvasive biomarker with excellent negative predictive values in the long term after pediatric intestinal/multivisceral transplant., (© Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.)
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- 2012
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4. MicroRNA signature of intestinal acute cellular rejection in formalin-fixed paraffin-embedded mucosal biopsies.
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Asaoka T, Sotolongo B, Island ER, Tryphonopoulos P, Selvaggi G, Moon J, Tekin A, Amador A, Levi DM, Garcia J, Smith L, Nishida S, Weppler D, Tzakis AG, and Ruiz P
- Subjects
- Acute Disease, Adolescent, Adult, Aged, Biopsy, Child, Child, Preschool, Female, Fixatives pharmacology, Formaldehyde pharmacology, Gene Expression Profiling, Graft Rejection metabolism, Graft Rejection pathology, Humans, In Situ Hybridization, Fluorescence, Infant, Infant, Newborn, Intestinal Mucosa metabolism, Intestine, Small metabolism, Intestine, Small pathology, Male, MicroRNAs biosynthesis, Middle Aged, Paraffin Embedding, Real-Time Polymerase Chain Reaction, Transplantation, Homologous, Young Adult, Gene Expression Regulation, Graft Rejection genetics, Intestinal Mucosa pathology, Intestine, Small transplantation, MicroRNAs genetics
- Abstract
Despite continuous improvement of immunosuppression, small bowel transplantation (SBT) is plagued by a high incidence of acute cellular rejection (ACR) that is frequently intractable. Therefore, there is a need to uncover novel insights that will lead to strategies to achieve better control of ACR. We hypothesized that particular miRNAs provide critical regulation of the intragraft immune response. The aim of our study was to identify miRNAs involved in intestinal ACR. We examined 26 small intestinal mucosal biopsies (AR/NR group; 15/11) obtained from recipients after SBT or multivisceral transplantation. We investigated the expression of 384 mature human miRNAs and 280 mRNAs associated with immune, inflammation and apoptosis processes. We identified differentially expressed 28 miRNAs and 58 mRNAs that characterized intestinal ACR. We found a strong positive correlation between the intragraft expression levels of three miRNAs (miR-142-3p, miR-886-3p and miR-132) and 17 mRNAs including CTLA4 and GZMB. We visualized these miRNAs within cells expressing CD3 and CD14 proteins in explanted intestinal allografts with severe ACR. Our data suggested that miRNAs have a critical role in the activation of infiltrating cells during intestinal ACR. These differences in miRNA expression patterns can be used to identify novel biomarkers and therapeutic targets for immunosuppressive agents., (© 2011 The American Society of Transplantation and the American Society of Transplant Surgeons.)
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- 2012
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5. Devastating intracardiac and aortic thrombosis: a case report of apparent catastrophic antiphospholipid syndrome during liver transplantation.
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Gologorsky E, Andrews DM, Gologorsky A, Sampathi V, Sundararaman L, Govindaswamy R, Raveh Y, Tzakis AG, and Pretto EA Jr
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- Antibodies, Anticardiolipin immunology, Antiphospholipid Syndrome diagnosis, Aorta physiopathology, Female, Heart Atria physiopathology, Heart Diseases etiology, Heart Diseases physiopathology, Heart Ventricles physiopathology, Humans, Immunoglobulin M immunology, Middle Aged, Thrombosis physiopathology, Antiphospholipid Syndrome complications, Liver Transplantation, Thrombosis etiology
- Abstract
Fewer than 80 cases of intracardiac thrombosis and intraoperative pulmonary thromboembolism during liver transplantation have been described. We present a patient who suffered an intraoperative fulminant intracardiac and aortic thrombosis and posthumously was found to have had high anticardiolipin immunoglobulin M concentration and markers of hyperfibrinolysis in preoperatively collected plasma. Hemostatic therapy in the presence of circulating antiphospholipid antibodies and the pathogenesis of a catastrophic antiphospholipid syndrome are discussed., (Copyright © 2011 Elsevier Inc. All rights reserved.)
- Published
- 2011
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6. Analysis of acute cellular rejection episodes in recipients of primary intestinal transplantation: a single center, 11-year experience.
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Selvaggi G, Gaynor JJ, Moon J, Kato T, Thompson J, Nishida S, Levi D, Ruiz P, Cantwell P, and Tzakis AG
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- Adolescent, Adult, Age Factors, Child, Child, Preschool, Female, Graft Rejection diagnosis, Graft Rejection physiopathology, Graft Survival physiology, Humans, Incidence, Infant, Intestines physiopathology, Longitudinal Studies, Male, Middle Aged, Organ Transplantation physiology, Predictive Value of Tests, Prognosis, Retrospective Studies, Severity of Illness Index, Time Factors, Graft Rejection pathology, Intestines pathology, Intestines transplantation, Organ Transplantation pathology
- Abstract
Intestinal transplantation has evolved over the years with major improvements in patient and graft survival. Acute cellular rejection of the intestine, however, still remains one of the most challenging aspects of postoperative management. We analyzed retrospectively collected data from 209 recipients of primary intestinal grafts at our institution over the past 11 years. A total of 290 episodes of biopsy-proven rejection requiring clinical treatment were analyzed. Rejection episodes doubled in length, on average, with each increasing grade (mild, moderate, severe). We observed increased incidence of overall rejection and particularly severe rejection in recipients of isolated intestinal and liver-intestine grafts in comparison with multivisceral grafts. Two rejection history variables had a significant negative impact on graft survival: the occurrence of a severe rejection episode and a rejection episode lasting >or=21 days. The lower incidence rate of severe rejection in recipients of multivisceral grafts might be due to a combination of increased donor lymphatic tissue and larger load of donor-derived immune competent cells present in the graft. The development of more effective monitoring and treatment protocols to prevent the occurrence of severe and/or lengthy rejection episodes is of critical importance for intestinal graft survival.
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- 2007
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7. Ten-year experience in porto-caval hemitransposition for liver transplantation in the presence of portal vein thrombosis.
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Selvaggi G, Weppler D, Nishida S, Moon J, Levi D, Kato T, and Tzakis AG
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- Adult, Anticoagulants therapeutic use, Female, Follow-Up Studies, Humans, Immunosuppression Therapy methods, Kidney physiology, Liver Diseases surgery, Liver Transplantation adverse effects, Liver Transplantation mortality, Longitudinal Studies, Male, Middle Aged, Portacaval Shunt, Surgical adverse effects, Portacaval Shunt, Surgical mortality, Survival Rate, Warfarin therapeutic use, Budd-Chiari Syndrome surgery, Liver Transplantation methods, Portacaval Shunt, Surgical methods, Portal Vein surgery
- Abstract
Porto-caval hemitransposition (PCH) in liver transplantation allows revascularization of the liver when the porto-mesenteric axis is thrombosed. We, here, review our experience over an 11-year period. A total of 23 patients underwent liver transplantation using PCH. Immunosuppression was based on tacrolimus, with sirolimus used in case of renal insufficiency. Most common diagnoses were hepatitis C, Laennec's, Budd-Chiari and cryptogenic cirrhosis. Six patients needed splenectomy prior to transplant, 5 during transplant, 1 post-transplant, 11 had no splenectomy. Overall survival was 60% at 1 year and 38% at 3 years, with 10 of 23 patients currently alive and the longest survivor at 9.3 years. Most common cause of death was sepsis/multisystem organ failure, followed by pulmonary embolism. A total of 7/23 patients experienced post-operative gastrointestinal bleeding episodes, 6/23 patients developed thrombosis of the vena cava (median 162 days post-op). Post-operative ascites was noted in almost all patients. Renal dysfunction was commonly seen even after the first month post-transplant. PCH offers a feasible option for liver transplantation in those patients with complex thrombosis of the mesenteric and portal circulation.
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- 2007
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8. Refractory ascites after liver transplantation: an analysis of 1058 liver transplant patients at a single center.
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Nishida S, Gaynor JJ, Nakamura N, Butt F, Illanes HG, Kadono J, Neff GW, Levi DM, Moon JI, Selvaggi G, Kato T, Ruiz P, Tzakis AG, and Madariaga JR
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Ascites therapy, Child, Child, Preschool, Female, Hepatitis C complications, Humans, Incidence, Male, Middle Aged, Prognosis, Risk Factors, Secondary Prevention, Ascites epidemiology, Ascites etiology, Liver Transplantation mortality
- Abstract
A retrospective study of 1058 liver transplant recipients was performed to determine: (i) the incidence, etiology, timing, clinical features and treatment of refractory ascites (RA), (ii) risk factors for RA development, (iii) predictors of RA disappearance, (iv) predictors of survival following RA and (v) the impact of RA on patient survival. Sixty-two patients (5.9%) developed RA and its disappearance occurred in 27/62 cases. Patients having hepatitis C virus (HCV) had a significantly higher hazard rate of developing RA (p < 0.00001). No other baseline characteristic was associated with RA. Cox stepwise regression analysis of the hazard rate of RA disappearance found two significant factors: HCV recurrence as the reason for developing RA implied a poorer outcome (p = 0.006), whereas an unknown reason implied a favorable outcome (p = 0.02). In addition, survival following RA was significantly poorer among patients having bacterial peritonitis or HCV recurrence. Finally, the mortality rate was significantly (nearly 8.6 times) higher in patients following RA development while it was ongoing (p < 0.00001); however, if the RA disappeared, then the additional risk of death also disappeared. This study illustrates the importance of developing an optimal treatment strategy to (i) effectively treat RA if it develops and (ii) prevent hepatitis C recurrence.
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- 2006
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9. Piggyback technique in adult orthotopic liver transplantation: an analysis of 1067 liver transplants at a single center.
- Author
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Nishida S, Nakamura N, Vaidya A, Levi DM, Kato T, Nery JR, Madariaga JR, Molina E, Ruiz P, Gyamfi A, and Tzakis AG
- Abstract
Background: Orthotopic liver transplantation (OLT) in adult patients has traditionally been performed using conventional caval reconstruction technique (CV) with veno-venous bypass. Recently, the piggyback technique (PB) without veno-venous bypass has begun to be widely used. The aim of this study was to assess the effect of routine use of PB on OLTs in adult patients., Patients and Methods: A retrospective analysis was undertaken of 1067 orthotopic cadaveric whole liver transplantations in adult patients treated between June 1994 and July 2001. PB was used as the routine procedure. Patient demographics, factors including cold ischemia time (CIT), warm ischemia time (WIT), operative time, transfusions, blood loss, and postoperative results were assessed. The effects of clinical factors on graft survival were assessed by univariate and multivariate analyses.In all, 918 transplantations (86%) were performed with PB. Blood transfusion, WIT, and usage of veno-venous bypass were less with PB. Seventy-five (8.3%) cases with PB had refractory ascites following OLT (p=NS). Five venous outflow stenosis cases (0.54%) with PB were noted (p=NS). The liver and renal function during the postoperative periods was similar. Overall 1-, 3-, and 5-year patient survival rates were 85%, 78%, and 72% with PB. Univariate analysis showed that cava reconstruction method, CIT, WIT, amount of transfusion, length of hospital stay, donor age, and tumor presence were significant factors influencing graft survival. Multivariate analysis further reinforced the fact that CIT, donor age, amount of transfusion, and hospital stay were prognostic factors for graft survival., Conclusions: PB can be performed safely in the majority of adult OLTs. Results of OLT with PB are as same as for CV. Liver function, renal function, morbidity, mortality, and patient and graft survival are similar to CV. However, amount of transfusion, WIT, and use of veno-venous bypass are less with PB.
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- 2006
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10. Liver and intestine transplantation in the United States, 1995-2004.
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Shiffman ML, Saab S, Feng S, Abecassis MI, Tzakis AG, Goodrich NP, and Schaubel DE
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- Adolescent, Adult, Aged, Child, Child, Preschool, Graft Survival, History, 20th Century, History, 21st Century, Humans, Immunosuppression Therapy, Infant, Liver Diseases therapy, Liver Transplantation statistics & numerical data, Middle Aged, Transplantation statistics & numerical data, Intestines pathology, Liver Transplantation history, Liver Transplantation trends, Transplantation history, Transplantation trends
- Abstract
Three years of survival data are now available and the impact of the model for end-stage liver disease (MELD) allocation system is becoming clear. After a decline in new registrants to the waiting list in 2002, the number increased to 10 856 new patients in 2004. Since the implementation of MELD, the percentage of patients who have been on the list for 1-2 years has declined from 24% to 19%. There has been a shift upward in the percentage of patients with higher MELD scores on the waiting list. An increasing percentage of adult living donor liver recipients are over the age of 50 years; from 1% in 1997 to 51% in 2004. Parents donating to children (93% of living donors in 1995), represented only 14% in 2004. Long-term adjusted patient survival declined with increasing recipient age in adults following either DDLT or LDLT. Cirrhosis caused by chronic hepatitis C virus (HCV) is the leading indication for liver transplantation and is associated with reduced long-term survival in recipients with HCV compared to those without HCV, 68% at 5 years compared to 76%. Although the intestine waiting list has more than doubled over the last decade, an increasing number of centers now perform intestinal transplantation with greater success.
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- 2006
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11. The role of donor bone marrow infusions in withdrawal of immunosuppression in adult liver allotransplantation.
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Tryphonopoulos P, Tzakis AG, Weppler D, Garcia-Morales R, Kato T, Madariaga JR, Levi DM, Nishida S, Moon J, Selvaggi G, Regev A, Nery C, Bejarano P, Khaled A, Kleiner G, Esquenazi V, Miller J, Ruiz P, and Ricordi C
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- Female, Humans, Male, Time Factors, Tissue Donors, Bone Marrow Transplantation, Graft Rejection therapy, Immunosuppression Therapy, Liver Transplantation
- Abstract
We investigated the role of donor bone marrow cell (DBMC) infusions in immunosuppression withdrawal in adult liver transplantation. Patients enrolled were at least 3 years post-transplantation, with stable graft function. Forty-five (study group: G1) received DBMC, and 59 (control group: G2) did not. Immunosuppression was reduced by one third upon enrollment, by another third the second year of the study and was completely withdrawn the third year. Patient and graft survival were similar between the two groups. Although rejection episodes were significantly less in G1 the first 2 years of the study (35% vs. 57%, p = 0.016), there was no significant difference overall (74% vs. 81%, p = 0.14). Until February 2004, 20 patients, 10 in each group, were immunosuppression free for 1-3 years. Approximately 20% of long-term survivors of liver transplantation can successfully discontinue their immunosuppression. DBMC infusions, do not increase this likelihood.
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- 2005
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12. Cytomegalovirus prevalence and transmission after islet allograft transplant in patients with type 1 diabetes mellitus.
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Hafiz MM, Poggioli R, Caulfield A, Messinger S, Geiger MC, Baidal DA, Froud T, Ferreira JV, Tzakis AG, Ricordi C, and Alejandro R
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- Adolescent, Adult, Aged, Cytomegalovirus immunology, Cytomegalovirus Infections immunology, Cytomegalovirus Infections transmission, Diabetes Mellitus, Type 1 virology, Female, Humans, Male, Middle Aged, Prevalence, Regression Analysis, Risk Factors, Tissue Donors, Cytomegalovirus Infections epidemiology, Diabetes Mellitus, Type 1 surgery, Islets of Langerhans Transplantation
- Abstract
Cytomegalovirus (CMV) serological status of transplant donors and recipients has important implications on antiviral prophylaxis, morbidity/mortality, donor selection and hospital stay. We evaluated CMV prevalence in our islet transplant candidates (ITC) in comparison with organ donors. We correlated the CMV serological status of our ITC with serology for Epstein-Barr virus and Parvovirus B19, auto-antibodies, patient's age, age at DM onset, duration of DM, gender, race, ABO group, HLA haplotype and C-peptide levels. Cytomegalovirus transmission after islet transplant using the Edmonton regimen was also evaluated. Cytomegalovirus seropositivity varied according to patient group, age, gender and race. Type 1 DM patients had reduced odds of CMV seropositivity when compared with organ donors. In all groups studied, older patients, females, and non-Caucasians were more likely to be CMV seropositive. In addition, no CMV reactivation, infection or disease was observed among our transplanted patients using this steroid-free regimen even after donor/recipient CMV mismatch.
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- 2004
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13. Competing risks analysis of predictors of delisting owing to tumor progression in liver transplant candidates with hepatocellular carcinoma.
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Yamashiki N, Gaynor JJ, Kato T, Reddy KR, Sobhonslidsuk A, Levi D, Nishida S, Madariaga J, Nery J, Schiff ER, and Tzakis AG
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- Carcinoma, Hepatocellular diagnosis, Carcinoma, Hepatocellular mortality, Carcinoma, Hepatocellular physiopathology, Female, Humans, Liver Neoplasms diagnosis, Liver Neoplasms mortality, Liver Neoplasms physiopathology, Male, Middle Aged, Prognosis, Regression Analysis, Carcinoma, Hepatocellular surgery, Liver Neoplasms surgery, Liver Transplantation, Risk Assessment
- Abstract
Orthotopic liver transplantation (OLT) is potentially curative for patients with early stage hepatocellular carcinoma (HCC). However, tumor progression before OLT remains a problem. Ninety-three patients were listed for transplantation with HCC or diagnosed with HCC following listing between March, 1997 and September, 2001. Modified TNM Stage was I/II in 82 patients and III in 11 patients. Seventy-one patients (76%) were transplanted with a median waiting time of 3.4 months, and 22 (24%) patients were delisted owing to tumor progression (14), noncompliance (5), and death from liver failure (3). Using a cox model competing risks approach, higher baseline alpha-fetoprotein (AFP) >or= 100 ng/mL was the only factor independently associated with a higher hazard rate of delisting owing to tumor progression (p = 0.00003), whereas four separate factors were independently associated with a lower hazard rate of transplantation: more recent listing year (1999-2001, p = 0.010), blood type O (p = 0.013), Stage I HCC (p = 0.029), and serum bilirubin < 4 mg/dL (p = 0.032). By logistic regression, AFP >/= 100 ng/mL was the only factor that significantly influenced the probability of delisting owing to tumor progression (p = 0.001). In conclusion, the initial AFP level may be useful along with tumor stage in defining an urgency score for liver transplant candidates with HCC.
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- 2004
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14. Immune responses and their regulation by donor bone marrow cells in clinical organ transplantation.
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Mathew JM, Garcia-Morales RO, Carreno M, Jin Y, Fuller L, Blomberg B, Cirocco R, Burke GW, Ciancio G, Ricordi C, Esquenazi V, Tzakis AG, and Miller J
- Subjects
- Histocompatibility Testing, Humans, Organ Transplantation, T-Lymphocytes immunology, Bone Marrow Cells immunology, Bone Marrow Transplantation, Kidney Transplantation immunology
- Abstract
Infusions of donor bone marrow derived cells (DBMC) continue to be tested in clinical protocols intended to induce specific immunologic tolerance of solid organ transplants based on the observations that donor-specific tolerance is induced this way in animal models. We studied the immunological effects of human DBMC infusions in renal transplantation using modifications in lymphoproliferation (MLR) and cytotoxicity (CML) assays. The salient observations and tentative conclusions are summarized in this review. Among many types of organs transplanted using DBMC at this center, it was found that the cadaver renal recipients (CAD) had significantly decreased chronic rejection and higher graft survival when compared to equivalent non-infused controls. DBMC infusion was also associated with a marginal and non-specific immune depression. It was also observed that the number of chimeric donor cells gradually increased in the iliac crest bone marrow compartment with a concomitant decrease in the peripheral blood and that the increase was more rapid in living-related donor (LRD)-kidney/DBMC recipients in spite of a lower number of DBMC infused (<25%) than in the CAD-kidney/DBMC group. In the LRD recipients with residual anti-donor responses, purified chimeric cells of either donor or recipient inhibited recipient immune responses to the donor significantly more strongly than the freshly obtained bone marrow from the specific donor or volunteer suggesting an active regulatory role for chimeric cells. A number of (non-chimeric) subpopulations of bone marrow cells including CD34(+) stem cells and the CD34(-) early progeny like CD38(+), CD2(+), CD5(+) and CD1(+) lymphoid cells as well as CD33(+) (but CD15(-)) myeloid cells down-regulated the MLR and CML responses of allogeneic PBMC stimulated with (autologous) donor spleen cells. These regulatory effects appeared to be refractory to the action of commonly used immunosuppressive drugs and occurred during the early phase of the immune response through cell-cell interactions. Most of these DBMC sub-populations had stimulatory capabilities, albeit markedly lower than donor spleen cells, but only through the indirect antigen presentation pathway. When co-cultured with allogeneic stimulators, purified CD34(+) cells were found to give rise both to CD3(-) TCRalphabeta(+), as well as CD3(+) TCRalphabeta(+) cells and, thereby, responded in MLR to allogeneic stimulation (but did not generate cytotoxic effector cells). Also, a number of DBMC subpopulations inhibited the CML and to a lesser extent the MLR, of autologous post-thymic responding T cells stimulated with allogeneic irradiated cells, mediated through soluble factors. Finally, non-chimeric DBMC also inhibited the proliferative and cytotoxic responses of autologous T cells to EBV antigens, inducing T suppressor cells, which in turn could inhibit autologous anti-EBV CTL generation and B cell anti-CMV antibody production. These studies all suggested a strong inhibitory property of a number of DBMC sub-populations in vitro and in vivo with the notion that they promote unresponsiveness.
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- 2003
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15. Transplantation of the abdominal wall.
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Levi DM, Tzakis AG, Kato T, Madariaga J, Mittal NK, Nery J, Nishida S, and Ruiz P
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- Abdominal Wall blood supply, Adipose Tissue transplantation, Adolescent, Adult, Alemtuzumab, Antibodies, Monoclonal therapeutic use, Antibodies, Monoclonal, Humanized, Antibodies, Neoplasm therapeutic use, Child, Child, Preschool, Fascia transplantation, Graft Rejection prevention & control, Humans, Immunosuppressive Agents therapeutic use, Infant, Liver Transplantation methods, Male, Middle Aged, Pancreas Transplantation methods, Skin Transplantation, Stomach transplantation, Surgical Flaps blood supply, Tacrolimus therapeutic use, Transplantation, Homologous, Treatment Outcome, Abdominal Wall surgery, Digestive System Surgical Procedures methods, Intestines transplantation, Rectus Abdominis transplantation
- Abstract
Background: Closure of the abdomen in patients undergoing intestinal transplantation can be extremely difficult, if not impossible. We describe our initial experience with abdominal wall allotransplantation to facilitate abdominal closure., Methods: We undertook nine cadaveric abdominal wall composite allograft transplants in eight patients. The graft's blood supply was based on the inferior epigastric vessels left in continuity with the donor femoral and iliac vessels. Skin biopsies were undertaken randomly and when rejection was suspected. Vessel patency was monitored by doppler ultrasound., Findings: Six patients have survived, five of whom have intact, viable abdominal wall grafts. Two patients have had a clinically mild episode of acute rejection of the skin of the abdominal wall that resolved with corticosteroid therapy. No clinically apparent graft-versus-host disease has been noted., Interpretation: Transplantation of an abdominal wall composite allograft can facilitate reconstruction and closure of the abdominal compartment in intestinal transplant recipients with complex abdominal wall defects.
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- 2003
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16. Adenovirus infection in pediatric liver and intestinal transplant recipients: utility of DNA detection by PCR.
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McLaughlin GE, Delis S, Kashimawo L, Cantwell GP, Mittal N, Cirocco RE, Ruiz P, Kato T, and Tzakis AG
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- Adenoviridae isolation & purification, Age Distribution, Child, Child, Preschool, Florida epidemiology, Humans, Ileum pathology, Incidence, Infant, Outcome and Process Assessment, Health Care, Sensitivity and Specificity, Survival Rate, Adenoviridae genetics, Adenovirus Infections, Human diagnosis, Adenovirus Infections, Human epidemiology, DNA, Viral isolation & purification, Intestines transplantation, Liver Transplantation statistics & numerical data, Polymerase Chain Reaction methods
- Abstract
To evaluate the incidence of adenovirus (AdV) infection in pediatric liver and intestinal transplant recipients, the records of patients with possible AdV infection were reviewed for demographic data, symptomatology, methods of diagnosis, treatment and outcome. To evaluate the impact of polymerase chain reaction (PCR) amplification and identification of AdV DNA as a diagnostic test, the incidence and outcome of AdV before and after the introduction of PCR were compared. Adenovirus infection was identified in 4.1% of liver recipients and 20.8% of intestinal transplant recipients. The overall incidence of AdV did not increase over time, even following the introduction of PCR for virus detection. The higher incidence of AdV in the pediatric intestinal transplant recipients may be attributed to the frequent application of PCR methodology to intestinal biopsy material. Detection of AdV by PCR was associated with reduced mortality compared with detection by culture, either because of earlier detection of invasive disease or because PCR detects the presence of latent as well as active AdV.
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- 2003
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17. A novel micro-cell-mediated lympholytic assay for the evaluation of regulatory cells in human alloreactive CTL responses.
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Mathew JM, Blomberg B, Fuller L, Burke GW, Ciancio G, Kenyon N, Ricordi C, Tzakis AG, Esquenazi V, and Miller J
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- Bone Marrow Cells immunology, Cytotoxicity Tests, Immunologic statistics & numerical data, Humans, In Vitro Techniques, Isoantigens, Kidney Transplantation immunology, Lymphocyte Culture Test, Mixed, Sensitivity and Specificity, T-Lymphocyte Subsets immunology, T-Lymphocytes, Regulatory immunology, Transplantation Immunology, Cytotoxicity Tests, Immunologic methods, T-Lymphocytes, Cytotoxic immunology
- Abstract
Since cell-mediated lympholysis (CML), the most commonly used in vitro experimental cytotoxic method for the evaluation of regulatory cells, requires large numbers of cells that are often the limiting factor, we have developed a new micro-cell-mediated lympholytic (m-CML) assay. Various numbers of responding cells were stimulated with equivalent numbers of allogeneic irradiated stimulator cells in the presence of (fivefold) serial dilutions of regulatory cells. On the 8th day, 4-h 51Cr-release assays were performed by adding 5000 labeled target cells from the corresponding stimulators to the cultures. Even though results that were comparable to the macro- (bulk) CML and MLR modulation experiments were obtained with all the cell combinations tested in the m-CML, the combinations with 50,000 responder cells and stimulating cells and dilutions of 25,000 to 40 modulator (regulatory) cells were found to be the most reproducible for assaying regulatory cell potency in vitro. Similarly, expression of the results as percentage inhibition using percent specific lysis values was the simplest method of calculation. This assay was standardized for the evaluation of the inhibitory activity of a variety of regulatory cells, including long-term cultures of cadaver-donor vertebral body bone marrow cells (vDBMC-L), in vitro generated CD8 positive and CD28 negative suppressor T cells and donor chimeric cells isolated from renal transplant recipients who had been perioperatively infused with donor bone marrow cells (DBMC). The results indicate that the m-CML assay is a sensitive and reliable micromethod with at least 10-fold fewer responders, stimulator and modulator cell numbers needed than macro-CML assays for the evaluation of regulatory cells obtained from a variety of immune systems in vitro.
- Published
- 2003
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18. Levels of mycophenolic acid and its glucuronide derivative in the plasma of liver, small bowel and kidney transplant patients receiving tacrolimus and cellcept combination therapy.
- Author
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Tsaroucha AK, Zucker K, Esquenazi V, de Faria L, Miller J, and Tzakis AG
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- Adolescent, Adult, Female, Humans, Male, Middle Aged, Mycophenolic Acid administration & dosage, Mycophenolic Acid metabolism, Tacrolimus metabolism, Glucuronides blood, Immunosuppressive Agents administration & dosage, Intestine, Small transplantation, Kidney Transplantation, Liver Transplantation, Mycophenolic Acid analogs & derivatives, Mycophenolic Acid blood, Tacrolimus administration & dosage
- Abstract
In order to help assess the usefulness of mycophenolate mofetil (MMF) as an immunosuppressive agent in recipients of organs other than kidneys, we measured the trough levels of the active metabolite of MMF, mycophenolic acid (MPA), and its inactive glucuronide derivative (MPAG), in the plasma of liver (n = 83) and small bowel transplant patients (n = 15) receiving MMF in combination with tacrolimus. These levels were compared with a group of renal transplant patients (n = 25) receiving the same drug regimen. All patient groups were otherwise comparable except the small bowel patient group which contained more pediatric patients (average age 18.7 +/- 3.9 years), and, therefore, received a higher average drug dose (in mg/kg). Despite this, these patients displayed the lowest levels of MPA of any group (0.39 +/- 0.08 microg/ml, P < 0.001 vs. 1.10 +/- 0.17 microg/ml for liver transplant patients, P < 0.001 or 2.46 +/- 0.37 microg/ml for renal transplant patients, P < 0.001). There were no statistically significant differences in MPAG levels between any of the groups. Although preliminary, these data demonstrate significant transplanted organ-specific differences in MMF pharmacology and/or bioavailability, and suggest the need for separate evaluation of MMF dosing for each transplant type.
- Published
- 2000
- Full Text
- View/download PDF
19. Recurrent Crohn's disease in transplanted bowel.
- Author
-
Sustento-Reodica N, Ruiz P, Rogers A, Viciana AL, Conn HO, and Tzakis AG
- Subjects
- Adult, Colon pathology, Female, Humans, Immunosuppressive Agents therapeutic use, Jejunostomy, Recurrence, Short Bowel Syndrome etiology, Short Bowel Syndrome surgery, Crohn Disease pathology, Crohn Disease surgery, Intestine, Small pathology, Intestine, Small transplantation
- Abstract
Background: Intestinal transplantation is used in patients with short-bowel syndrome after repeated resections for Crohn's disease. We report the apparent clinical recurrence of Crohn's disease in a transplanted intestine., Methods and Findings: The patient, a 33-year-old Hispanic woman, underwent small-bowel transplantation in December, 1994. Immunosuppression with tacrolimus, methylprednisolone, bone-marrow infusions, and OKT3 was given. In July, 1995, the patient had recurrent abdominal symptoms. The histological diagnosis of Crohn's disease was established by the independent interpretations of four experienced gastrointestinal histopathologists., Interpretation: The prompt appearance of this autoimmune disorder (within 6 months of transplantation), despite massive immunosuppression may provide important insights into the nature of Crohn's disease and of the recurrence of autoimmune disease during immunosuppression.
- Published
- 1997
- Full Text
- View/download PDF
20. Hepatitis-B-virus resistance to lamivudine given for recurrent infection after orthotopic liver transplantation.
- Author
-
Bartholomew MM, Jansen RW, Jeffers LJ, Reddy KR, Johnson LC, Bunzendahl H, Condreay LD, Tzakis AG, Schiff ER, and Brown NA
- Subjects
- DNA, Viral analysis, DNA-Directed DNA Polymerase genetics, Drug Resistance, Microbial genetics, Hepatitis B complications, Hepatitis B virology, Hepatitis B virus enzymology, Hepatitis B virus genetics, Humans, Lamivudine therapeutic use, Liver Failure etiology, Liver Failure surgery, Male, Microbial Sensitivity Tests, Middle Aged, Point Mutation, Polymerase Chain Reaction, Recurrence, Antiviral Agents pharmacology, Hepatitis B drug therapy, Hepatitis B virus drug effects, Lamivudine pharmacology, Liver Transplantation
- Abstract
Background: Orthotopic liver transplantation for end-stage hepatitis-B-virus (HBV) infection is commonly complicated by recurrence of HBV. Lamivudine, a cytosine nucleoside analogue, has been shown to suppress HBV infection. We report the development of resistance to lamivudine in three patients who underwent transplantation for end-stage liver disease secondary to hepatitis B., Methods: Two of the patients received lamivudine for recurrent HBV infection after transplantation, whereas the third patient began treatment 1 month before transplantation in an attempt to prevent HBV recurrence after transplantation. The three patients initially responded well to treatment, but viral recurrence occurred after 9-10 months of treatment in all patients. HBV DNA was amplified from serum and sequenced through a conserved polymerase domain-the tyrosine, methionine, aspartate, aspartate (YMDD) locus. We assessed the susceptibility of HBV to lamivudine by infecting primary human hepatocytes with serum taken before the start of treatment and after recurrence in varying concentrations of lamivudine., Findings: DNA sequencing showed a common mutation within the YMDD locus of the HBV polymerase gene in all patients during lamivudine treatment. In hepatocyte cultures infected with pretreatment serum, HBV DNA concentrations were reduced to less than 6% of those in control cultures by addition of lamivudine in concentrations as low as 0.03 mumol/L. By contrast, in cultures treated with serum taken after recurrence, HBV DNA concentrations did not fall below 20% of control values, even with lamivudine at 30 mumol/L., Interpretation: Resistance to lamivudine has been reported in HIV patients with mutations in the YMDD locus of the polymerase gene. Our findings indicate a common mechanism of lamivudine resistance for HIV and HBV that involves similar point mutations in homologous domains of the viral polymerases.
- Published
- 1997
- Full Text
- View/download PDF
21. Rapid development of extensive macrovascular calcifications in a type I diabetic patient.
- Author
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Carroll PB, Rilo HL, Zeng YJ, Ricordi C, Shapiro R, and Tzakis AG
- Subjects
- Adult, Calcinosis diagnostic imaging, Diabetes Mellitus, Type 1 surgery, Diabetic Angiopathies diagnostic imaging, Diabetic Nephropathies surgery, Diabetic Nephropathies therapy, Female, Humans, Peritoneal Dialysis, Radiography, Renal Dialysis, Uremia complications, Uremia physiopathology, Calcinosis physiopathology, Diabetes Mellitus, Type 1 physiopathology, Diabetic Angiopathies physiopathology, Diabetic Nephropathies physiopathology, Islets of Langerhans Transplantation, Kidney Transplantation
- Abstract
This is a case report of a 35-year-old woman with a 15-year history of type I diabetes mellitus, who developed extensive macrovascular calcifications of the abdominal aorta and all its tributaries within 7 months of developing renal insufficiency. The patient was maintained on hemodialysis and peritoneal dialysis for a total of 3 months, then underwent combined cadaveric renal and pancreatic islet transplantation. Although some vascular calcifications are known to occur in elderly patients and in patients with long-standing uremia, it was the rapidity and extent of development of these lesions in this young woman that is astonishing.
- Published
- 1991
- Full Text
- View/download PDF
22. Pancreatic islet transplantation after upper abdominal exenteration and liver replacement.
- Author
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Tzakis AG, Ricordi C, Alejandro R, Zeng Y, Fung JJ, Todo S, Demetris AJ, Mintz DH, and Starzl TE
- Subjects
- Adolescent, Adult, Child, Female, Humans, Islets of Langerhans physiology, Male, Middle Aged, Pancreas surgery, Postoperative Care, Survival Analysis, Abdomen surgery, Islets of Langerhans Transplantation, Liver Transplantation
- Abstract
Nine patients who became diabetic after upper-abdominal exenteration and liver transplantation were given pancreatic islet-cell grafts obtained from the liver donor (eight cases), a third-party donor (one), or both (four). Two patients were diabetic when they died of infections after 48 and 109 days, as was a third patient who died of tumour recurrence after 178 days. The other 6 are alive 101-186 days postoperatively, and five are insulin-free or on insulin only during night-time parenteral alimentation. C-peptide increased 1.7 to 3.3 fold in response to intravenous glucose in these five patients who have had glycosylated haemoglobin in the high normal range. However, the kinetics of the C-peptide responses to intravenous glucose in all eight patients tested revealed an absent first-phase release and a delayed peak response consistent with transplantation and/or engraftment of a suboptimal islet cell mass. The longest survivor, who requires neither parenteral alimentation nor insulin, is the first unequivocal example of successful clinical islet-cell transplantation.
- Published
- 1990
- Full Text
- View/download PDF
23. FK 506 in steroid-resistant focal sclerosing glomerulonephritis of childhood.
- Author
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McCauley J, Tzakis AG, Fung JJ, Todo S, and Starzl TE
- Subjects
- Adult, Child, Preschool, Drug Resistance, Humans, Male, Prednisone therapeutic use, Tacrolimus, Anti-Bacterial Agents therapeutic use, Glomerulonephritis drug therapy, Glomerulosclerosis, Focal Segmental drug therapy, Immunosuppressive Agents therapeutic use
- Published
- 1990
- Full Text
- View/download PDF
24. Progress in liver transplantation.
- Author
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Gordon RD, Iwatsuki S, Esquivel CO, Makowka L, Todo S, Tzakis AG, Marsh JW Jr, and Starzl TE
- Subjects
- Biliary Tract Surgical Procedures, Cyclosporins therapeutic use, Humans, Methods, Tissue and Organ Procurement, Liver Diseases surgery, Liver Transplantation
- Published
- 1988
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