Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 17 de 17
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Ann Intern Med ; 176(2): 174-181, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36645888

RESUMO

BACKGROUND: Primary infection with or reactivation of Epstein-Barr virus (EBV) can occur after liver transplant (LT) and can lead to posttransplant lymphoproliferative disease (PTLD). In pediatric LT, an EBV-DNA viral load (EBV VL) monitoring strategy, including the reduction of immunosuppression, has led to a lower incidence of PTLD. For adult LT recipients with less primary infection and more EBV reactivation, it is unknown whether this strategy is effective. OBJECTIVE: To examine the effect of an EBV VL monitoring strategy on the incidence of PTLD after LT in adults. DESIGN: Cohort study. SETTING: Two university medical centers in the Netherlands. PATIENTS: Adult recipients of first LT in Leiden between September 2003 and January 2017 with an EBV VL monitoring strategy formed the monitoring group (M1), recipients of first LT in Rotterdam between January 2003 and January 2017 without such a strategy formed the contemporary control group (C1), and those who had transplants in Leiden between September 1992 and September 2003 or Rotterdam between 1986 and January 2003 formed the historical control groups (M0 and C0, respectively). MEASUREMENTS: Influence of EBV VL monitoring on incidence of PTLD. RESULTS: After inverse probability of treatment weighting of the 4 groups to achieve a balance among the groups for important patient characteristics, differences within hospitals between the historical and recent era in cumulative incidences-expressed as the number of events per 1000 patients measured at 5-, 10-, and 15-year follow-up-showed fewer events in the contemporary era in both centers. This difference was considerably larger in the monitoring center, whereas the 95% CI included the null value of 0 for point estimates. LIMITATION: Retrospective, low statistical power, and incompletely balanced groups, and non-EBV PTLD cannot be prevented. CONCLUSION: Monitoring EBV VL may reduce PTLD incidence after LT in adults; larger studies are warranted. PRIMARY FUNDING SOURCE: None.


Assuntos
Infecções por Vírus Epstein-Barr , Transplante de Fígado , Transtornos Linfoproliferativos , Humanos , Criança , Adulto , Herpesvirus Humano 4/genética , Infecções por Vírus Epstein-Barr/epidemiologia , Estudos de Coortes , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Carga Viral , Transtornos Linfoproliferativos/epidemiologia , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/prevenção & controle , DNA Viral
2.
Liver Transpl ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37698933

RESUMO

Post-transplant lymphoproliferative disease (PTLD) is a rare but serious complication of liver transplantation (LT) with morbidity and mortality. The risk factors for PTLD in adults are ill-defined. This study aimed to assess the risk factors for PTLD after LT in adults. All adult LT recipients between 1986 and 2016 from 2 centers in the Netherlands were included, with follow-up until 2020. PTLD was diagnosed according to the World Health Organization (WHO) classification. Potential risk factors for PTLD were assessed using multivariate Cox regression analysis. A total of 1281 patients were included, of whom 29 (2.3%) developed PTLD. Results show that independent risk factors for PTLD after LT in adults were no Epstein-Barr virus load monitoring strategy, primary sclerosing cholangitis as an indication for LT, era (historic era linked to more intense long-term immunosuppression), and Epstein-Barr virus-seronegative recipient. No other independent risk factors were identified in this study. Of the 207 patients with primary sclerosing cholangitis as an indication for LT, 13 (6.3%) developed PTLD versus 16 out of 1074 (1.5%) patients with other underlying liver diseases (log-rank p <0.001). The yearly PTLD incidence was higher in the first year than in the later years after LT (2.4%/y vs. 0.6%/y) for primary sclerosing cholangitis, but not for other indications (0.16%/y). In Epstein-Barr virus-seronegative recipients PTLD occurred earlier after LT, while in 97% of seropositive recipients it could occur very late after LT.

3.
Drug Metab Rev ; 52(3): 438-454, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32551945

RESUMO

To predict the absorption, distribution, metabolism and excretion (ADME) profile of candidate drugs a variety of preclinical models can be applied. The ADME and toxicological behavior of newly developed drugs are often investigated prior to assessment in humans, which is associated with long time-lines and high costs. Therefore, good predictions of ADME profiles earlier in the drug development process are very valuable. Good prediction of intestinal absorption and renal and biliary excretion remain especially difficult, as there is an interplay of active transport and metabolism involved. To study these processes, including enterohepatic circulation, ex vivo tissue models are highly relevant and can be regarded as the bridge between in vitro and in vivo models. In this review the current in vitro, in vivo and in more detail ex vivo models for studying pharmacokinetics in health and disease are discussed. Additionally, we propose novel models, i.e., perfused whole-organs, which we envision will generate valuable pharmacokinetic information in the future due to improved translation to the in vivo situation. These machine-perfused organ models will be particularly interesting in combination with biomarkers for assessing the functionality of transporter and CYP450 proteins.


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Fígado/enzimologia , Modelos Biológicos , Preparações Farmacêuticas/metabolismo , Farmacocinética , Animais , Biomarcadores Farmacológicos , Biópsia , Interações Medicamentosas , Humanos , Proteínas de Membrana Transportadoras/metabolismo , Taxa de Depuração Metabólica , Preparações Farmacêuticas/administração & dosagem , Distribuição Tecidual
4.
Clin Transplant ; 32(2)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29193362

RESUMO

Donor-specific alloantibodies (DSA) have been associated with rejection and shorter graft survival after orthotopic liver transplantation (OLT). We examined the role of DSA in nonanastomotic biliary strictures (NAS) after OLT. Patients receiving first OLT who developed NAS (n = 68) and a control group without NAS (n = 83), with pre-OLT and 12 months post-OLT serum samples, were included. DSA were specified using the Luminex single antigen test. Risk factors for NAS and graft survival were analyzed. The presence of preformed DSA was not significantly different between patients with NAS and controls (P = .89). After 12 months, 26.5% of NAS patients and 16.9% of controls had generated de novo DSA (P = .15). Neither de novo class I DSA nor de novo class II DSA were associated with NAS. De novo DSA generally developed after the diagnosis of NAS. Time-dependent regression analysis identified both NAS (aHR 8.05, CI 3.28 - 19.77, P < .01) and de novo class II DSA (aHR 2.84, CI 1.38 - 5.82, P < .01) as independent risk factors for graft loss. Preformed or de novo DSA were not associated with the development of NAS. However, NAS as well as de novo class II DSA were independent risk factors for graft loss after OLT.


Assuntos
Doenças dos Ductos Biliares/sangue , Constrição Patológica/sangue , Rejeição de Enxerto/sangue , Antígenos HLA/imunologia , Isoanticorpos/sangue , Transplante de Fígado/efeitos adversos , Adulto , Doenças dos Ductos Biliares/diagnóstico , Doenças dos Ductos Biliares/etiologia , Constrição Patológica/diagnóstico , Constrição Patológica/etiologia , Feminino , Seguimentos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Prognóstico , Fatores de Risco
5.
Transpl Int ; 31(6): 590-599, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29150966

RESUMO

Studies from the USA and Nordic countries indicate primary sclerosing cholangitis (PSC) patients have low mortality on the liver transplantation (LTx) waiting list. However, this may vary among geographical areas. Therefore, we compared waiting list mortality and post-transplant survival between laboratory model for end-stage liver disease (LM) and MELD exception (ME)-prioritized PSC and non-PSC candidates in a nationwide study in the Netherlands. A retrospective analysis of patients waitlisted from 2006 to 2013 was conducted. A total of 852 candidates (146 PSC) were waitlisted of whom 609 (71.5%) underwent LTx and 159 (18.7%) died before transplantation. None of the ME PSC patients died, and they had a higher probability of LTx than LM PSC [HR obtained by considering ME as a time-dependent covariate (HRME 9.86; 95% CI 6.14-15.85)] and ME non-PSC patients (HRME 4.60; 95% CI 3.78-5.61). After liver transplantation, PSC patients alive at 3 years of follow-up had a higher probability of relisting than non-PSC patients (HR 7.94; 95% CI 1.98-31.85) but a significantly lower mortality (HR 0.51; 95% CI 0.27-0.95). In conclusion, current LTx prioritization advantages PSC patients on the LTx waiting list. Receiving ME points is strongly associated with timely LTx.


Assuntos
Colangite Esclerosante/cirurgia , Política de Saúde , Falência Hepática/cirurgia , Transplante de Fígado/métodos , Obtenção de Tecidos e Órgãos/métodos , Listas de Espera , Adulto , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Países Baixos , Probabilidade , Estudos Retrospectivos , Medição de Risco , Fatores de Tempo , Doadores de Tecidos
6.
Liver Transpl ; 22(4): 420-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26600096

RESUMO

The aim of the present study was to assess whether flushing the donor liver with urokinase immediately before implantation reduces the incidence of nonanastomotic biliary strictures (NASs) after liver transplantation, without causing increased blood loss, analyzed as a historical cohort study. Between January 2005 and October 2012, all liver (re-)transplantations were included. Of the 185 liver transplant recipients included, 63 donor livers between January 2010 and October 2012 received urokinase (study group), whereas the donor liver of 122 consecutive recipients, who served as a historical control group, between January 2005 and January 2010 did not receive urokinase. Basic donor (Eurotransplant donor risk index) and recipient (age, body mass index, laboratory Model for End-Stage Liver Disease score) characteristics did not significantly differ in both groups. Thirty-three recipients developed NASs: 22 in the control group (18%) and 11 (17.5%) in the study group (P = 0.68). Analyzed separately for donation after circulatory death (P = 0.42) or donation after brain death (P = 0.89), there was no difference between the groups in incidence of NAS. Of all the recipients developing NAS, 7 (21%) needed retransplantation and all others were treated conservatively. Autologous blood transfusion requirements did not differ significantly between both groups (P = 0.91), whereas interestingly, more heterologous blood transfusions were needed in the control group (P < 0.001). This study has its limitations by its retrospective character. A multi-institutional prospective study could clarify this issue. In conclusion, arterial flushing of the liver with urokinase immediately before implantation did not lead to a lower incidence of NAS in this study, nor did it lead to increased blood loss.


Assuntos
Doenças Biliares/epidemiologia , Transplante de Fígado/métodos , Hemorragia Pós-Operatória/epidemiologia , Reoperação/métodos , Ativador de Plasminogênio Tipo Uroquinase/uso terapêutico , Adulto , Doenças Biliares/etiologia , Estudos de Coortes , Constrição Patológica/epidemiologia , Constrição Patológica/etiologia , Feminino , Sobrevivência de Enxerto , Humanos , Incidência , Hepatopatias/cirurgia , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Hemorragia Pós-Operatória/etiologia , Reoperação/efeitos adversos , Estudos Retrospectivos , Doadores de Tecidos , Ativador de Plasminogênio Tipo Uroquinase/efeitos adversos
7.
Transpl Int ; 28(4): 492-501, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25601020

RESUMO

Orthotopic liver transplantation (OLT) with donation after circulatory death (DCD) often leads to a higher first week peak alanine aminotransferase (ALT) and a higher rate of biliary nonanastomotic strictures (NAS) as compared to donation after brain death (DBD). This retrospective study was to evaluate whether an association exists between peak ALT and the development of NAS in OLT with livers from DBD (n = 399) or DCD (n = 97) from two transplantation centers. Optimal cutoff value of peak ALT for risk of development of NAS post-DCD-OLT was 1300 IU/l. The 4-year cumulative incidence of NAS after DCD-OLT was 49.5% in patients with a high ALT peak post-OLT, compared with 11.3% in patients with a low ALT peak. (P < 0.001). No relation between peak ALT and NAS was observed after DBD-OLT. Multivariate analysis revealed peak ALT ≥1300 IU/l [adjusted hazard ratio (aHR) = 3.71, confidence interval (CI) (1.26-10.91)] and donor age [aHR = 1.04, CI 1.00-1.07] to be independently associated with development of NAS post-DCD-OLT. A peak ALT of <1300 IU/l carries a risk for NAS similar to DBD-OLT. Thus, in DCD-OLT, but not in DBD-OLT, peak ALT discriminates patients at high or low risk for NAS.


Assuntos
Alanina Transaminase/sangue , Doenças dos Ductos Biliares/sangue , Transplante de Fígado , Complicações Pós-Operatórias/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças dos Ductos Biliares/diagnóstico , Doenças dos Ductos Biliares/etiologia , Colangite Esclerosante/diagnóstico , Estudos de Coortes , Constrição Patológica/sangue , Constrição Patológica/diagnóstico , Constrição Patológica/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Traumatismo por Reperfusão/complicações , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
8.
Transpl Int ; 26(4): 411-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23398215

RESUMO

This study aims to perform a detailed prospective observational multicenter cost-effectiveness study by comparing liver transplantations with donation after brain death (DBD) and donation after cardiac death (DCD) grafts. All liver transplantations in the three Dutch liver transplant centers between 2004 and 2009 were included with 1-year follow-up. Primary outcome parameter was cost per life year after transplantation. Secondary outcome parameters were 1-year patient and graft survival, complications, and patient-level costs. From 382 recipients that underwent 423 liver transplantations, 293 were primarily transplanted with DBD and 89 with DCD organs. Baseline characteristics were not different between both groups. The Donor Risk Index was significantly different as were cold and warm ischemic time. Ward stay was significantly longer in DCD transplantations. Patient and graft survival were not significantly different. Patients receiving DCD organs had more and more severe complications. The cost per life year for DBD was € 88,913 compared to € 112,376 for DCD. This difference was statistically significant. DCD livers have more and more severe complications, more reinterventions and consequently higher costs than DBD livers. However, patient and graft survival was not different in this study. Reimbursement should be differentiated to better accommodate DCD transplantations.


Assuntos
Morte , Transplante de Fígado/economia , Obtenção de Tecidos e Órgãos/economia , Análise Custo-Benefício , Feminino , Seguimentos , Humanos , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
J Clin Transl Hepatol ; 11(4): 839-849, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37408814

RESUMO

Background and Aims: Previous trials comparing cyclosporine and tacrolimus after liver transplantation (LT) showed conflicting results. Most used trough monitoring for cyclosporine (C0), leading to less accurate dosing than with 2-h monitoring (C2). Only one larger trial compared C2 with tacrolimus based on trough level (T0) after LT, with similar treated biopsy-proven acute rejection (tBPAR) and graft loss, while a smaller trial had less tBPAR with C2 compared to T0. Therefore, it is still unclear which calcineurin inhibitor is preferred after LT. We aimed to demonstrate superior efficacy (tBPAR), tolerability, and safety of C2 or T0 after first LT. Methods: Patients after first LT were randomized to C2 or T0. tBPAR, patient- and graft survival, safety and tolerability were the main endpoints, with analysis by Fisher test, Kaplan-Meier survival analysis and log-rank test. Results: In intention-to-treat analysis 84 patients on C2 and 85 on T0 were included. Cumulative incidence of tBPAR C2 vs. T0 was 17.7% vs. 8.4% at 3 months (p=0.104), and 21.9% vs. 9.7% at 6 and 12 months (p=0.049). One-year cumulative mortality C2 vs. T0 was 15.5% vs. 5.9% (p=0.049) and graft loss 23.8% vs. 9.4% (p=0.015). Serum triglyceride and LDL-cholesterol was lower with T0 than with C2. Incidence of diarrhea in T0 vs, C2 was 64% vs. 31% (p≤0.001), with no other differences in safety and tolerability. Conclusions: In the first year after LT immunosuppression with T0 leads to less tBPAR and better patient-/re-transplant-free survival as compared to C2.

10.
Clin Pharmacol Ther ; 114(1): 137-147, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37042227

RESUMO

Realistic models predicting hepatobiliary processes in health and disease are lacking. We therefore aimed to develop a physiologically relevant human liver model consisting of normothermic machine perfusion (NMP) of explanted diseased human livers that can assess hepatic extraction, clearance, biliary excretion, and drug-drug interaction (DDI). Eleven livers were included in the study, seven with a cirrhotic and four with a noncirrhotic disease background. After explantation of the diseased liver, NMP was initiated. After 120 minutes of perfusion, a drug cocktail (rosuvastatin, digoxin, metformin, and furosemide; OATP1B1/1B3, P-gp, BCRP, and OCT1 model compounds) was administered to the portal vein and 120 minutes later, a second bolus of the drug cocktail was co-administered with perpetrator drugs to study relevant DDIs. The explanted livers showed good viability and functionality during 360 minutes of NMP. Hepatic extraction ratios close to in vivo reported values were measured. Hepatic clearance of rosuvastatin and digoxin showed to be the most affected by cirrhosis with an increase in maximum plasma concentration (Cmax ) of 11.50 and 2.89 times, respectively, compared with noncirrhotic livers. No major differences were observed for metformin and furosemide. Interaction of rosuvastatin or digoxin with perpetrator drugs were more pronounced in noncirrhotic livers compared with cirrhotic livers. Our results demonstrated that NMP of human diseased explanted livers is an excellent model to assess hepatic extraction, clearance, biliary excretion, and DDI. Gaining insight into pharmacokinetic profiles of OATP1B1/1B3, P-gp, BCRP, and OCT1 model compounds is a first step toward studying transporter functions in diseased livers.


Assuntos
Furosemida , Metformina , Humanos , Rosuvastatina Cálcica/farmacocinética , Furosemida/farmacocinética , Eliminação Hepatobiliar , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Fígado/metabolismo , Cirrose Hepática , Metformina/farmacocinética , Digoxina/farmacocinética , Interações Medicamentosas
11.
BJS Open ; 7(2)2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-37032423

RESUMO

BACKGROUND: The Mayo protocol for liver transplantation in patients with unresectable perihilar cholangiocarcinoma is based on strict selection and neoadjuvant chemoradiotherapy. The role of neoadjuvant chemoradiotherapy in this scenario remains unclear. The aim of this study was to compare outcomes after transplantation for perihilar cholangiocarcinoma using strict selection criteria, either with or without neoadjuvant chemoradiotherapy. METHODS: This was an international, multicentre, retrospective cohort study of patients who underwent transplantation between 2011 and 2020 for unresectable perihilar cholangiocarcinoma using the Mayo selection criteria and receiving neoadjuvant chemoradiotherapy or not receiving neoadjuvant chemoradiotherapy. Endpoints were post-transplant survival, post-transplant morbidity rate, and time to recurrence. RESULTS: Of 49 patients who underwent liver transplantation for perihilar cholangiocarcinoma, 27 received neoadjuvant chemoradiotherapy and 22 did not. Overall 1-, 3-, and 5-year post-transplantation survival rates were 65 per cent, 51 per cent and 41 per cent respectively in the group receiving neoadjuvant chemoradiotherapy and 91 per cent, 68 per cent and 53 per cent respectively in the group not receiving neoadjuvant chemoradiotherapy (1-year hazards ratio (HR) 4.55 (95 per cent c.i. 0.98 to 21.13), P = 0.053; 3-year HR 2.07 (95 per cent c.i. 0.78 to 5.54), P = 0.146; 5-year HR 1.71 (95 per cent c.i. 0.71 to 4.09), P = 0.229). Hepatic vascular complications were more frequent in the group receiving neoadjuvant chemoradiotherapy compared with the group not receiving neoadjuvant chemoradiotherapy (nine of 27 versus two of 22, P = 0.045). In multivariable analysis, tumour recurrence occurred less frequently in the group receiving neoadjuvant chemoradiotherapy (HR 0.30 (95 per cent c.i. 0.09 to 0.97), P = 0.044). CONCLUSION: In selected patients undergoing liver transplantation for perihilar cholangiocarcinoma, neoadjuvant chemoradiotherapy resulted in a lower risk of tumour recurrence, but was associated with a higher rate of early hepatic vascular complications. Adjustments in neoadjuvant chemoradiotherapy reducing the risk of hepatic vascular complications, such as omitting radiotherapy, may further improve the outcome in patients undergoing liver transplantation for perihilar cholangiocarcinoma.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Transplante de Fígado , Humanos , Tumor de Klatskin/cirurgia , Tumor de Klatskin/patologia , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Ductos Biliares Intra-Hepáticos/patologia
12.
Liver Int ; 31(8): 1110-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21745270

RESUMO

BACKGROUND: Nonanastomotic biliary strictures (NAS) are a serious complication after orthotopic liver transplantation (OLT). Matrix metalloproteinases (MMPs) are involved in connective tissue remodelling in chronic liver disease and complications after OLT. AIM: To evaluate the relationship between MMP-2 and MMP-9 gene polymorphisms and NAS. METHODS: MMP-2 (-1306 C/T) and MMP-9 (-1562 C/T) gene promoter polymorphisms were analysed in 314 recipient-donor combinations. Serum levels of these MMPs were determined in subgroups of patients as well. NAS were identified with various radiological imaging studies performed within 4 years after OLT and defined as any stricture, dilation or irregularity of the intra- or extrahepatic bile ducts of the liver graft followed by an intervention, after exclusion of hepatic artery thrombosis and anastomotic strictures. RESULTS: The average incidence of NAS was 15%. The major clinical risk factor for the development of NAS was PSC in the recipient. The presence of the MMP-2 CT genotype in donor and/or recipient was associated with a significantly higher incidence of NAS, up to 29% when both donor and recipient had the MMP-2 CT genotype (P=0.003). In the multivariate analyses, pre-OLT PSC (hazard ratio 2.1, P=0.02) and MMP-2 CT genotype (hazard ratio 3.5, P=0.003) were found to be independent risk factors for the development of NAS after OLT. No obvious association was found between NAS and the MMP-9 genotype and serum levels of the MMPs. CONCLUSION: MMP-2 CT genotype of donor and recipient is an independent risk factor, in addition to PSC, for the development of NAS after OLT.


Assuntos
Colestase/genética , Transplante de Fígado/efeitos adversos , Metaloproteinase 2 da Matriz/genética , Polimorfismo Genético , Adolescente , Adulto , Idoso , Distribuição de Qui-Quadrado , Colangite Esclerosante/complicações , Colangite Esclerosante/cirurgia , Colestase/diagnóstico por imagem , Colestase/enzimologia , Constrição Patológica , Feminino , Frequência do Gene , Predisposição Genética para Doença , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 9 da Matriz/genética , Pessoa de Meia-Idade , Países Baixos , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais , Radiografia , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
13.
Curr Opin Organ Transplant ; 16(2): 239-42, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21415827

RESUMO

PURPOSE OF REVIEW: Liver transplantation following donation after cardiac death (DCD) continues to be a subject for heated debate. Opinion is divided in the literature as to who benefits the most from receiving a liver from a DCD donor. This review will focus on some important questions regarding the outcome of transplantation and the selection and matching of donor and recipient. RECENT FINDINGS: Liver transplantation with an organ from a donor after cardiac death is becoming an accepted way to treat patients on the waiting list with end-stage liver disease. However, there are still some major issues to address such as ischemic-type biliary lesions, retransplantation rates, criteria for donor and patient selection and whether conversion of donation after brain death to DCD exists. Accepting a DCD liver has the potential for reduced recipient quality of life after transplant. Death on the waiting list must be balanced against the inherent risks of a DCD liver. SUMMARY: Success of liver transplantation is mostly measured as graft and patient survival. DCD liver transplantation is a potential tool to decrease mortality on the waiting list. Careful selection and matching of donor organ and recipient can lead to good outcomes. However, ischemic-type biliary lesions after DCD liver transplantation remain an important obstacle to overcome and have a serious impact on quality of life after transplantation.


Assuntos
Seleção do Doador , Transplante de Fígado/efeitos adversos , Seleção de Pacientes , Doadores de Tecidos/provisão & distribuição , Sobrevivência de Enxerto , Humanos , Transplante de Fígado/mortalidade , Guias de Prática Clínica como Assunto , Qualidade de Vida , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Listas de Espera/mortalidade
15.
ChemSusChem ; 13(12): 3172-3179, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32253816

RESUMO

Nickel-molybdenum (Ni-Mo) alloys are well studied as highly effective electrocatalyst cathodes for water splitting. Understanding deactivation pathways is a key to improving the performance of these catalysts. In this study, in situ characterization by UV/Vis spectroscopy and AFM of the morphology and Mo leaching of an Ni-Mo electrocatalyst was performed with the goal of understanding the stability and related Mo leaching mechanism. Switching the potential towards higher overpotentials results in a nonlinear change in Mo leaching. Multiple processes are proposed to take place, such as a decrease in the extent of Mo oxidation at the cathode induced by more strongly reducing potentials, while simultaneously the increase in the local pH at the cathode due to the hydrogen evolution reaction causes more Mo leaching. The change in capacitance of these materials depends strongly on the change in surface composition and not only on the surface area. In situ UV/Vis spectroscopy showed that Mo leaching is a continuous process over the course of 4 h of operation. Finally, the material was deposited on different substrates and the effect on Ni-Mo stability was studied. The substrate has a significant, albeit complex, influence on the stability and activity of Ni-Mo cathodes. In terms of stability in 1 m KOH, Ni-Mo was found to be best deposited on stainless steel substrates operated at low overpotentials, on which it showed nearly no change in capacitance and exhibited low Mo leaching.

17.
Transplantation ; 93(9): 887-94, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22538450

RESUMO

BACKGROUND: Early calcineurin inhibitor (CNI) withdrawal with mycophenolate mofetil (MMF) has not become routine practice, due to concerns about excess acute rejection. Therapeutic drug monitoring may be advantageous when the CNI or MMF is withdrawn. METHODS: This prospective, randomized, concentration-controlled withdrawal study enrolled 177 stable renal transplant recipients on maintenance CNI-based immunosuppression, combined with steroids and MMF. After the feasibility phase of the study, patients were randomized to MMF-withdrawal (target area under the time-concentration curve-cyclosporine: 3250 ng·hr/mL or tacrolimus: 120 ng·hr/mL) or CNI-withdrawal (target area under the time-concentration curve-mycophenolic acid: 75 µg·hr/mL). RESULTS: The estimated glomerular filtration rate (modification of diet in renal disease) remained significantly better after CNI elimination (59.5±2.1 mL/min vs. 51.1±2.1 mL/min, P = 0.006) up to 3 years and resulted in less functional decline, including the subgroup with an estimated glomerular filtration rate less than 50 mL/min at baseline (P = 0.03). At 6 months, one patient in the MMF-withdrawal group (1.3%) and three in the CNI-withdrawal group (3.8%) experienced acute rejection (P = 0.62). The defined higher mycophenolic acid exposure was well tolerated. CONCLUSION: These data indicate that with time the large majority of stable renal transplant recipients can be safely reduced to dual therapy with MMF or CNIs, applying concentration-controlled dosing. CNI-free patients, including those with moderate renal allograft dysfunction, have the benefit of improved renal function, whereas the risk of acute rejection after late withdrawal is low.


Assuntos
Inibidores de Calcineurina , Rejeição de Enxerto/tratamento farmacológico , Transplante de Rim , Ácido Micofenólico/análogos & derivados , Doença Aguda , Biópsia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/administração & dosagem , Estudos de Viabilidade , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/metabolismo , Rejeição de Enxerto/fisiopatologia , Sobrevivência de Enxerto , Humanos , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Estudos Prospectivos , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA