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1.
Placenta ; 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38570213

RESUMO

The ex vivo human placenta perfusion model has proven to be clinically relevant to study transfer- and fetal exposure of various drugs. Although the method has existed for a long period, the setup of the perfusion model has not been generalized yet. This review aims to summarize the setups of ex vivo placental perfusion models used to examine drug transfer across the placenta to identify generalized properties and differences across setups. A literature search was carried out in PubMed September 26, 2022. Studies were labeled as relevant when information was reported, between 2000 and 2022, on the setups of ex vivo placental perfusion models used to study drug transfer across the placenta. The placenta perfusion process, and the data extraction, was divided into phases of preparation, control, drug, and experimental reflecting the chronological timeline of the different phases during the entire placental perfusion process. 135 studies describing an ex vivo human placental perfusion experiment were included. Among included studies, the majority (78.5%) analyzed drug perfusion in maternal to fetal direction, 18% evaluated bi-directional drug perfusion, 3% under equilibrium conditions, and one study investigated drug perfusion in fetal to maternal direction. This literature review facilitates the comparison of studies that employ similar placenta perfusion protocols for drug transfer studies and reveals significant disparities in the setup of these ex vivo placental perfusion models. Due to interlaboratory variability, perfusion studies are not readily comparable or interchangeable. Therefore, a stepwise protocol with multiple checkpoints for validating placental perfusion is needed.

2.
Curr Diab Rep ; 19(11): 129, 2019 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-31741132

RESUMO

PURPOSE OF REVIEW: Beta-cell replacement is the best therapeutic option for patients with type 1 diabetes. Because of donor scarcity, more extended criteria donors are used for transplantation. Donation after circulatory death donors (DCD) are not commonly used for pancreas transplantation, because of the supposed higher risk of complications. This review gives an overview on the pathophysiology, risk factors, and outcome in DCD transplantation and discusses different preservation methods. RECENT FINDINGS: Studies on outcomes of DCD pancreata show similar results compared with those of donation after brain death (DBD), when accumulation of other risk factors is avoided. Hypothermic machine perfusion is shown to be a safe method to improve graft viability in experimental settings. DCD should not be the sole reason to decline a pancreas for transplantation. Adequate donor selection and improved preservation techniques can lead to enhanced pancreas utilization and outcome.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Preservação de Órgãos/métodos , Transplante de Pâncreas/métodos , Morte , Diabetes Mellitus Tipo 1/fisiopatologia , Seleção do Doador , Sobrevivência de Enxerto/fisiologia , Humanos , Transplante de Pâncreas/efeitos adversos , Transplante de Pâncreas/psicologia , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos , Resultado do Tratamento
3.
Br J Surg ; 106(6): 711-719, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30919435

RESUMO

BACKGROUND: Data on chronic pain after kidney donation are sparse. The aim of this study was to assess the incidence of chronic pain after hand-assisted laparoscopic nephrectomy. METHODS: Living kidney donors who donated between 2011 and 2017 at the University Medical Centre Groningen were included. All patients underwent hand-assisted laparoscopic donor nephrectomy. Postdonation pain and movement disabilities were assessed using the Carolinas Comfort Scale (CCS) and a visual analogue scale (VAS). The prevalence, severity of pain and the need for analgesics were reported. RESULTS: Some 333 living kidney donors with a mean age of 56 years were included. At a median of 19 (i.q.r. 10-33) months after donation, 82 donors (24·6 per cent) had a CCS score above 0, of which 58 (71 per cent) had a CCS score of at least 2 and 57 (70 per cent) reported movement limitations. Some 110 donors (33·0 per cent) had a VAS score of more than 0. Complaints mainly occurred during bending over (12·3 per cent) and exercising (12·4 per cent). Thirty-two donors (9·7 per cent) required analgesics during follow-up between donation and the time of measurement, and six of 82 (7 per cent) reported chronic inguinal pain. In multivariable analysis, donor age (odds ratio (OR) 0·97, 95 per cent c.i. 0·95 to 0·99; P = 0·020) and length of hospital stay (OR 1·21, 1·01 to 1·51; P = 0·041) were independently associated with chronic pain. CONCLUSION: One-quarter of donors experienced chronic postdonation pain or discomfort, most of which was bothersome. Younger donors and those with a longer postoperative hospital stay had more symptoms.


Assuntos
Dor Crônica , Laparoscopia Assistida com a Mão , Transplante de Rim , Doadores Vivos , Nefrectomia/métodos , Dor Pós-Operatória , Adulto , Idoso , Dor Crônica/diagnóstico , Dor Crônica/epidemiologia , Dor Crônica/etiologia , Feminino , Seguimentos , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/etiologia , Prevalência , Estudos Retrospectivos , Fatores de Risco
4.
Sci Rep ; 8(1): 4405, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29535334

RESUMO

Hepatic and renal energy status prior to transplantation correlates with graft survival. However, effects of brain death (BD) on organ-specific energy status are largely unknown. We studied metabolism, perfusion, oxygen consumption, and mitochondrial function in the liver and kidneys following BD. BD was induced in mechanically-ventilated rats, inflating an epidurally-placed Fogarty-catheter, with sham-operated rats as controls. A 9.4T-preclinical MRI system measured hourly oxygen availability (BOLD-related R2*) and perfusion (T1-weighted). After 4 hrs, tissue was collected, mitochondria isolated and assessed with high-resolution respirometry. Quantitative proteomics, qPCR, and biochemistry was performed on stored tissue/plasma. Following BD, the liver increased glycolytic gene expression (Pfk-1) with decreased glycogen stores, while the kidneys increased anaerobic- (Ldha) and decreased gluconeogenic-related gene expression (Pck-1). Hepatic oxygen consumption increased, while renal perfusion decreased. ATP levels dropped in both organs while mitochondrial respiration and complex I/ATP synthase activity were unaffected. In conclusion, the liver responds to increased metabolic demands during BD, enhancing aerobic metabolism with functional mitochondria. The kidneys shift towards anaerobic energy production while renal perfusion decreases. Our findings highlight the need for an organ-specific approach to assess and optimise graft quality prior to transplantation, to optimise hepatic metabolic conditions and improve renal perfusion while supporting cellular detoxification.


Assuntos
Adaptação Fisiológica , Morte Encefálica/metabolismo , Metabolismo Energético , Animais , Biomarcadores , Expressão Gênica , Rim/metabolismo , Fígado/metabolismo , Masculino , Mitocôndrias/metabolismo , Especificidade de Órgãos , Estresse Oxidativo , Consumo de Oxigênio , Perfusão , Ratos
5.
Br J Anaesth ; 118(5): 720-732, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28510740

RESUMO

BACKGROUND: Kidney transplantation is associated with harmful processes affecting the viability of the graft. One of these processes is associated with the phenomenon of ischaemia-reperfusion injury. Anaesthetic conditioning is a widely described strategy to attenuate ischaemia-reperfusion injury. We therefore conducted the Volatile Anaesthetic Protection of Renal Transplants-1 trial, a pilot project evaluating the influence of two anaesthetic regimens, propofol- vs sevoflurane-based anaesthesia, on biochemical and clinical outcomes in living donor kidney transplantation. METHODS: Sixty couples were randomly assigned to the following three groups: PROP (donor and recipient propofol), SEVO (donor and recipient sevoflurane), and PROSE (donor propofol and recipient sevoflurane). The primary outcome was renal injury reflected by urinary biomarkers. The follow-up period was 2 yr. RESULTS: Three couples were excluded, leaving 57 couples for analysis. Concentrations of kidney injury molecule-1 (KIM-1), N -acetyl-ß- d -glucosaminidase (NAG), and heart-type fatty acid binding protein (H-FABP) in the first urine upon reperfusion showed no differences. On day 2, KIM-1 concentrations were higher in SEVO [952.8 (interquartile range 311.8-1893.0) pg mmol -1 ] compared with PROP [301.2 (202.0-504.7) pg mmol -1 ]. This was the same for NAG: SEVO, 1.835 (1.162-2.457) IU mmol -1 vs PROP, 1.078 (0.819-1.713) IU mmol -1 . Concentrations of H-FABP showed no differences. Measured glomerular filtration rate at 3, 6, and 12 months showed no difference. After 2 yr, there was a difference in the acute rejection rate ( P =0.039). Post hoc testing revealed a difference between PROP (35%) and PROSE (5%; P =0.020). The difference between PROP and SEVO (11%) was not significant ( P =0.110). CONCLUSIONS: The SEVO group showed higher urinary KIM-1 and NAG concentrations in living donor kidney transplantation on the second day after transplantation. This was not reflected in inferior graft outcome. CLINICAL TRIAL REGISTRATION: NCT01248871.


Assuntos
Anestesia por Inalação , Anestesia Intravenosa , Anestésicos Inalatórios , Anestésicos Intravenosos , Transplante de Rim/métodos , Doadores Vivos , Propofol , Sevoflurano , Injúria Renal Aguda/etiologia , Adolescente , Adulto , Idoso , Biomarcadores/urina , Proteína 3 Ligante de Ácido Graxo/urina , Feminino , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Terapia de Imunossupressão , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/urina , Projetos Piloto , Estudos Prospectivos , Traumatismo por Reperfusão/prevenção & controle , Adulto Jovem
6.
Br J Surg ; 104(8): 1010-1019, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28488729

RESUMO

BACKGROUND: Anastomotic leakage is a potential major complication after colorectal surgery. The C-seal was developed to help reduce the clinical leakage rate. It is an intraluminal sheath that is stapled proximal to a colorectal anastomosis, covering it intraluminally and thus preventing intestinal leakage in case of anastomotic dehiscence. The C-seal trial was initiated to evaluate the efficacy of the C-seal in reducing anastomotic leakage in stapled colorectal anastomoses. METHODS: This RCT was performed in 41 hospitals in the Netherlands, Germany, France, Hungary and Spain. Patients undergoing elective surgery with a stapled colorectal anastomosis less than 15 cm from the anal verge were eligible. Included patients were randomized to the C-seal and control groups, stratified for centre, anastomotic height and intention to create a defunctioning stoma. Primary outcome was anastomotic leakage requiring invasive treatment. RESULTS: Between December 2011 and December 2013, 402 patients were included in the trial, 202 in the C-seal group and 200 in the control group. Anastomotic leakage was diagnosed in 31 patients (7·7 per cent), with a 10·4 per cent leak rate in the C-seal group and 5·0 per cent in the control group (P = 0·060). Male sex showed a trend towards a higher leak rate (P = 0·055). Construction of a defunctioning stoma led to a lower leakage rate, although this was not significant (P = 0·095). CONCLUSION: C-seal application in stapled colorectal anastomoses does not reduce anastomotic leakage. Registration number: NTR3080 (http://www.trialregister.nl/trialreg/index.asp).


Assuntos
Implantes Absorvíveis , Fístula Anastomótica/prevenção & controle , Colo/cirurgia , Reto/cirurgia , Idoso , Anastomose Cirúrgica/efeitos adversos , Neoplasias Colorretais/cirurgia , Divertículo do Colo/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Grampeamento Cirúrgico/efeitos adversos
7.
Clin Exp Immunol ; 184(3): 378-88, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26874675

RESUMO

Complement activation is of major importance in numerous pathological conditions. Therefore, targeted complement inhibition is a promising therapeutic strategy. C1-esterase inhibitor (C1-INH) controls activation of the classical pathway (CP) and the lectin pathway (LP). However, conflicting data exist on inhibition of the alternative pathway (AP) by C1-INH. The inhibitory capacity of C1-INH for the CP is potentiated by heparin and other glycosaminoglycans, but no data exist for the LP and AP. The current study investigates the effects of C1-INH in the presence or absence of different clinically used heparinoids on the CP, LP and AP. Furthermore, the combined effects of heparinoids and C1-INH on coagulation were investigated. C1-INH, heparinoids or combinations were analysed in a dose-dependent fashion in the presence of pooled serum. Functional complement activities were measured simultaneously using the Wielisa(®) -kit. The activated partial thrombin time was determined using an automated coagulation analyser. The results showed that all three complement pathways were inhibited significantly by C1-INH or heparinoids. Next to their individual effects on complement activation, heparinoids also enhanced the inhibitory capacity of C1-INH significantly on the CP and LP. For the AP, significant potentiation of C1-INH by heparinoids was found; however, this was restricted to certain concentration ranges. At low concentrations the effect on blood coagulation by combining heparinoids with C1-INH was minimal. In conclusion, our study shows significant potentiating effects of heparinoids on the inhibition of all complement pathways by C1-INH. Therefore, their combined use is a promising and a potentially cost-effective treatment option for complement-mediated diseases.


Assuntos
Ativação do Complemento/efeitos dos fármacos , Proteína Inibidora do Complemento C1/farmacologia , Heparinoides/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Via Alternativa do Complemento/efeitos dos fármacos , Via Clássica do Complemento/efeitos dos fármacos , Lectina de Ligação a Manose da Via do Complemento/efeitos dos fármacos , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Sinergismo Farmacológico , Humanos , Tempo de Tromboplastina Parcial
8.
Am J Transplant ; 16(5): 1421-40, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26602379

RESUMO

In an era where we are becoming more reliant on vulnerable kidneys for transplantation from older donors, there is an urgent need to understand how brain death leads to kidney dysfunction and, hence, how this can be prevented. Using a rodent model of hemorrhagic stroke and next-generation proteomic and metabolomic technologies, we aimed to delineate which key cellular processes are perturbed in the kidney after brain death. Pathway analysis of the proteomic signature of kidneys from brain-dead donors revealed large-scale changes in mitochondrial proteins that were associated with altered mitochondrial activity and morphological evidence of mitochondrial injury. We identified an increase in a number of glycolytic proteins and lactate production, suggesting a shift toward anaerobic metabolism. Higher amounts of succinate were found in the brain death group, in conjunction with increased markers of oxidative stress. We characterized the responsiveness of hypoxia inducible factors and found this correlated with post-brain death mean arterial pressures. Brain death leads to metabolic disturbances in the kidney and alterations in mitochondrial function and reactive oxygen species generation. This metabolic disturbance and alteration in mitochondrial function may lead to further cellular injury. Conditioning the brain-dead organ donor by altering metabolism could be a novel approach to ameliorate this brain death-induced kidney injury.


Assuntos
Biomarcadores/análise , Morte Encefálica/fisiopatologia , Rim/fisiopatologia , Metabolômica/métodos , Estresse Oxidativo/genética , Proteômica/métodos , Animais , Masculino , Ratos , Ratos Endogâmicos F344 , Transdução de Sinais
9.
Br J Pharmacol ; 172(6): 1494-504, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24962324

RESUMO

BACKGROUND AND PURPOSE: Hypertension is an important mediator of cardiac damage and remodelling. Hydrogen sulfide (H2S) is an endogenously produced gasotransmitter with cardioprotective properties. However, it is not yet in clinical use. We, therefore, investigated the protective effects of sodium thiosulfate (STS), a clinically applicable H2 S donor substance, in angiotensin II (Ang II)-induced hypertensive cardiac disease in rats. EXPERIMENTAL APPROACH: Male Sprague Dawley rats were infused with Ang II (435 ng kg min(-1)) or saline (control) for 3 weeks via s.c. placed osmotic minipumps. During these 3 weeks, rats received i.p. injections of either STS, NaHS or vehicle (0.9% NaCl). KEY RESULTS: Compared with controls, Ang II infusion caused an increase in systolic and diastolic BP with associated cardiac damage as evidenced by cardiac hypertrophy, an increase in atrial natriuretic peptide (ANP) mRNA, cardiac fibrosis and increased oxidative stress. Treatment with NaHS and STS prevented the development of hypertension and the increase in ANP mRNA levels. Furthermore, the degree of cardiac hypertrophy, the extent of histological fibrosis in combination with the expression of profibrotic genes and the levels of oxidative stress were all significantly decreased. CONCLUSIONS AND IMPLICATIONS: Ang II-induced hypertensive cardiac disease can be attenuated by treatment with STS and NaHS. Although BP regulation is the most plausible mechanism of cardiac protection, the antifibrotic and antioxidant properties of released sulfide may also contribute to their effects. Our data show that H2 S might be a valuable addition to the already existing antihypertensive and cardioprotective therapies.


Assuntos
Sulfeto de Hidrogênio/metabolismo , Hipertensão/tratamento farmacológico , Sulfetos/farmacologia , Tiossulfatos/farmacologia , Angiotensina II/toxicidade , Animais , Anti-Hipertensivos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/etiologia , Cardiomegalia/prevenção & controle , Modelos Animais de Doenças , Hipertensão/complicações , Hipertensão/fisiopatologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
10.
Am J Transplant ; 13(12): 3067-75, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24266966

RESUMO

Once patients with kidney disease progress to end-stage renal failure, transplantation is the preferred option of treatment resulting in improved quality of life and reduced mortality compared to dialysis. Although 1-year survival has improved considerably, graft and patient survival in the long term have not been concurrent, and therefore new tools to improve long-term graft and patient survival are warranted. Over the past decades, the gasotransmitters nitric oxide (NO), carbon monoxide (CO) and hydrogen sulfide (H2S) have emerged as potent cytoprotective mediators in various diseases. All three gasotransmitters are endogenously produced messenger molecules that possess vasodilatory, anti-apoptotic, anti-inflammatory and anti-oxidant properties by influencing an array of intracellular signaling processes. Although many regulatory functions of gasotransmitters have overlapping actions, differences have also been reported. In addition, crosstalk between NO, CO and H2S results in synergistic regulatory effects. Endogenous and exogenous manipulation of gasotransmitter levels modulates several processes involved in renal transplantation. This review focuses on mechanisms of gas-mediated cytoprotection and complex interactions between gasotransmitters in renal transplantation.


Assuntos
Monóxido de Carbono/química , Gasotransmissores/química , Sulfeto de Hidrogênio/química , Falência Renal Crônica/terapia , Transplante de Rim/métodos , Óxido Nítrico/química , Animais , Apoptose , Citoproteção , Humanos , Incidência , Falência Renal Crônica/fisiopatologia , Camundongos , Estresse Oxidativo , Prevalência , Transdução de Sinais
11.
Am J Transplant ; 13(5): 1327-35, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23463950

RESUMO

In contrast to traditional static cold preservation of donor livers, normothermic machine perfusion may reduce preservation injury, improve graft viability and potentially allows ex vivo assessment of graft viability before transplantation. We have studied the feasibility of normothermic machine perfusion in four discarded human donor livers. Normothermic machine perfusion consisted of pressure and temperature controlled pulsatile perfusion of the hepatic artery and continuous portal perfusion for 6 h. Two hollow fiber membrane oxygenators provided oxygenation of the perfusion fluid. Biochemical markers in the perfusion fluid reflected minimal hepatic injury and improving function. Lactate levels decreased to normal values, reflecting active metabolism by the liver (mean lactate 10.0 ± 2.3 mmol/L at 30 min to 2.3 ± 1.2 mmol/L at 6 h). Bile production was observed throughout the 6 h perfusion period (mean rate 8.16 ± 0.65 g/h after the first hour). Histological examination before and after 6 h of perfusion showed well-preserved liver morphology without signs of additional hepatocellular ischemia, biliary injury or sinusoidal damage. In conclusion, this study shows that normothermic machine perfusion of human donor livers is technically feasible. It allows assessment of graft viability before transplantation, which opens new avenues for organ selection, therapeutic interventions and preconditioning.


Assuntos
Sobrevivência de Enxerto , Precondicionamento Isquêmico/métodos , Transplante de Fígado , Fígado/irrigação sanguínea , Preservação de Órgãos/métodos , Perfusão/métodos , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Temperatura
12.
Am J Transplant ; 13(4): 875-882, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23398742

RESUMO

Kidneys retrieved from brain-dead donors have impaired allograft function after transplantation compared to kidneys from living donors. Donor brain death (BD) triggers inflammatory responses, including both systemic and local complement activation. The mechanism by which systemic activated complement contributes to allograft injury remains to be elucidated. The aim of this study was to investigate systemic C5a release after BD in human donors and direct effects of C5a on human renal tissue. C5a levels were measured in plasma from living and brain-dead donors. Renal C5aR gene and protein expression in living and brain-dead donors was investigated in renal pretransplantation biopsies. The direct effect of C5a on human renal tissue was investigated by stimulating human kidney slices with C5a using a newly developed precision-cut method. Elevated C5a levels were found in plasma from brain-dead donors in concert with induced C5aR expression in donor kidney biopsies. Exposure of precision-cut human kidney slices to C5a induced gene expression of pro-inflammatory cytokines IL-1 beta, IL-6 and IL-8. In conclusion, these findings suggest that systemic generation of C5a mediates renal inflammation in brain-dead donor grafts via tubular C5a-C5aR interaction. This study also introduces a novel in vitro technique to analyze renal cells in their biological environment.


Assuntos
Morte Encefálica/patologia , Complemento C5a/metabolismo , Inflamação/patologia , Rim/patologia , Receptores de Complemento/metabolismo , Biópsia , Ensaio de Imunoadsorção Enzimática , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Imuno-Histoquímica , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Rim/metabolismo , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Receptor da Anafilatoxina C5a
13.
Am J Transplant ; 12(3): 660-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22176838

RESUMO

Local renal complement activation by the donor kidney plays an important role in the pathogenesis of renal injury inherent to kidney transplantation. Contradictory results were reported about the protective effects of the donor C3F allotype on renal allograft outcome. We investigated the influence of the donor C3F allotype on renal transplant outcome, taking all different donor types into account. C3 allotypes of 1265 donor-recipient pairs were determined and divided into four genotypic groups according to the C3F allotype of the donor and the recipient. The four genotypic groups were analyzed for association with primary nonfunction (PNF), delayed graft function, acute rejection, death-censored graft survival and patient survival. Considering all donor types, multivariable analysis found no association of the donor C3F allotype with renal allograft outcome. Also, for living and deceased brain-dead donors, no association with allograft outcome was found. Post hoc subgroup analysis within deceased cardiac dead (DCD) donors revealed an independent protective association of donor C3F allotype with PNF. This study shows that the donor C3F allotype is not associated with renal allograft outcome after kidney transplantation. Subgroup analysis within DCD donors revealed an independent protective association of the donor C3F allotype with PNF, which is preliminary and warrants further validation.


Assuntos
Complemento C3/genética , Rejeição de Enxerto/genética , Parada Cardíaca , Transplante de Rim/mortalidade , Polimorfismo Genético/genética , Doadores de Tecidos , Adulto , DNA/genética , Função Retardada do Enxerto , Feminino , Genótipo , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fatores de Risco , Taxa de Sobrevida , Transplante Homólogo , Resultado do Tratamento
14.
Am J Transplant ; 11(10): 2214-20, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21834917

RESUMO

Vascular renal resistance (RR) during hypothermic machine perfusion (HMP) is frequently used in kidney graft quality assessment. However, the association between RR and outcome has never been prospectively validated. Prospectively collected RR values of 302 machine-perfused deceased donor kidneys of all types (standard and extended criteria donor kidneys and kidneys donated after cardiac death), transplanted without prior knowledge of these RR values, were studied. In this cohort, we determined the association between RR and delayed graft function (DGF) and 1-year graft survival. The RR (mmHg/mL/min) at the end of HMP was an independent risk factor for DGF (odds ratio 38.1 [1.56-934]; p = 0.026) [corrected] but the predictive value of RR was low, reflected by a c-statistic of the receiver operator characteristic curve of 0.58. The RR was also found to be an independent risk factor for 1-year graft failure (hazard ratio 12.33 [1.11-136.85]; p = 0.004). Determinants of transplant outcome are multifactorial in nature and this study identifies RR as an additional parameter to take into account when evaluating graft quality and estimating the likelihood of successful outcome. However, RR as a stand-alone quality assessment tool cannot be used to predict outcome with sufficient precision.


Assuntos
Hipotermia Induzida , Rim , Doadores de Tecidos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Transplante de Rim , Pessoa de Meia-Idade , Perfusão , Prognóstico , Adulto Jovem
15.
J Thromb Haemost ; 9(10): 1959-65, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21762465

RESUMO

BACKGROUND: Brain death is associated with a systemic inflammatory response resulting in diminished organ function in individuals transplanted with organs from brain dead donors. As inflammation is accompanied by activation of coagulation, we hypothesized that activation of hemostasis occurs in brain dead organ donors. OBJECTIVES: To assess the hemostatic status in brain dead organ donors. PATIENTS AND METHODS: In this study, we systematically assessed the hemostatic system in samples taken from 30 brain dead donors. As controls, blood samples from 30 living kidney donors were included. RESULTS AND CONCLUSIONS: Compared with the living donors, brain dead donors showed significant platelet activation (assessed by glycocalicin plasma levels), and a profound dysbalance in the von Willebrand factor/ADAMTS13 axis, which is key in platelet attachment to damaged vasculature. Furthermore, compared with the living donors, brain dead donors showed a significantly increased activation of secondary hemostasis with formation of fibrin (assessed by plasma levels of prothrombin fragment 1 + 2, fibrinopeptide A and D-dimer). Finally, brain dead donors showed profound hypofibrinolysis as assessed by a global clot lysis assay, which was attributed to substantially elevated plasma levels of plasminogen activator inhibitor type 1. Collectively, our results show activation of hemostasis and dysregulated fibrinolysis in brain dead organ donors. This prothrombotic state may contribute to formation of microthrombi in transplantable organs, which potentially contributes to deterioration of organ function.


Assuntos
Morte Encefálica , Hemostasia , Doadores de Tecidos , Proteínas ADAM/metabolismo , Proteína ADAMTS13 , Coagulação Sanguínea , Fibrina/biossíntese , Humanos , Fator de von Willebrand/metabolismo
17.
Am J Transplant ; 9(8): 1752-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19522876

RESUMO

With more marginal deceased donors affecting graft viability, there is a need for specific parameters to assess kidney graft quality at the time of organ procurement in the deceased donor. Recently, kidney injury molecule-1 (Kim-1) was described as an early biomarker of renal proximal tubular damage. We assessed Kim-1 in a small animal brain death model as an early and noninvasive marker for donor-derived injury related to brain death and its sequelae, with subsequent confirmation in human donors. In rat kidney, real-time PCR revealed a 46-fold Kim-1 gene upregulation after 4 h of brain death. In situ hybridization showed proximal tubular Kim-1 localization, which was confirmed by immunohistochemistry. Also, Luminex assay showed a 6.6-fold Kim-1 rise in urine after 4 h of brain death. In human donors, 2.5-fold kidney injury molecule-1 (KIM-1) gene upregulation and 2-fold higher urine levels were found in donation after brain death (DBD) donors compared to living kidney donors. Multiple regression analysis showed that urinary KIM-1 at brain death diagnosis was a positive predictor of recipient serum creatinine, 14 days (p < 0.001) and 1 year (p < 0.05) after kidney transplantation. In conclusion, we think that Kim-1 is a promising novel marker for the early, organ specific and noninvasive detection of brain death-induced donor kidney damage.


Assuntos
Morte Encefálica/metabolismo , Moléculas de Adesão Celular/metabolismo , Transplante de Rim/fisiologia , Rim/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores Virais/metabolismo , Obtenção de Tecidos e Órgãos , Animais , Biomarcadores/metabolismo , Biópsia , Modelos Animais de Doenças , Feminino , Sobrevivência de Enxerto/fisiologia , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Rim/patologia , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Ratos , Ratos Endogâmicos F344 , Análise de Regressão
18.
Ned Tijdschr Geneeskd ; 152(13): 737-41, 2008 Mar 29.
Artigo em Holandês | MEDLINE | ID: mdl-18461889

RESUMO

Organ preservation is a critical link in the chain of donation and transplantation and has a significant effect on post-transplant graft function and graft survival. Clinically, the most widely used form of preservation is static cold storage, which is based on the reduction of cellular metabolism by hypothermia. Although static cold storage is simple and effective, it is questionable whether it still meets present day requirements. Due to the persistent shortage of donors, increasing numbers of organs are being accepted from older and non-heart-beating donors. Organs from such donors may benefit from a more dynamic method of preservation: hypothermic machine perfusion.


Assuntos
Hipotermia Induzida/métodos , Preservação de Órgãos/normas , Perfusão/métodos , Temperatura Baixa , Sobrevivência de Enxerto , Humanos , Soluções para Preservação de Órgãos
19.
Clin Exp Immunol ; 152(2): 311-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18341609

RESUMO

Hypothermic preservation of solid allografts causes profound damage of vascular endothelial cells. This, in turn, might activate innate immunity. In the present study we employed an in vitro model to study to what extent supernatants of damaged endothelial cells are able to activate innate immunity and to study the nature of these signals. The expression of high mobility group box 1 (HMGB1) and adhesion molecules on human umbilical vein endothelial cell was studied by immunofluorescence, fluorescence activated cell sorter and Western blotting. Cytokine production was performed by enzyme-linked immunosorbent assay. HMGB1 expression was lost completely in endothelial cells after hypothermic preservation. This was associated with cell damage as it occurred only in untreated endothelial cell but not in cells rendered resistant to hypothermia-mediated damage by dopamine treatment. Only supernatants from hypothermia susceptible cells up-regulated the expression of interleukin (IL)-8 and adhesion molecules in cultured endothelial cells in an HMGB1-dependent manner. In whole blood assays, both supernatants of hypothermia susceptible and resistant cells inhibited tumour necrosis factor (TNF)-alpha production concomitantly with an increased IL-10 secretion. The activity of the supernatants was already found after 6 h of hypothermic preservation, and paralleled the decrease in intracellular adenosine triphosphate (ATP) levels. Modulation of TNF-alpha and IL-10 production by these supernatants was abrogated completely by prior treatment with adenosine deaminase and was similar to the response of an A2R agonist. Our study demonstrates that both HMGB1 and adenosine are released during hypothermic preservation. While release of HMGB1 is caused by cell damage, release of adenosine seems to be related to ATP hydrolysis, occurring in both susceptible and resistant cells.


Assuntos
Adenosina/metabolismo , Endotélio Vascular/metabolismo , Proteína HMGB1/metabolismo , Refrigeração , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Humanos , Interleucina-10/biossíntese , Interleucina-8/metabolismo , Lipopolissacarídeos/imunologia , Fator de Necrose Tumoral alfa/biossíntese
20.
Kidney Int ; 72(7): 797-805, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17653138

RESUMO

Major improvements in immunosuppressive treatment, surgical techniques, and treatment of post-transplant complications have contributed considerably to improved outcome in renal transplantation over the past decades. Yet, these accomplishments have not led to similar improvements in transplant outcome when the results of living and deceased donors are compared. The enormous demand for donor kidneys has allowed for the increase in acceptance of suboptimal donors. The use of brain dead patients as organ donors has had a tremendous positive influence on the number of renal transplants. Unfortunately, the physiologically abnormal state of brain death has a negative effect on transplant outcome. The fact that transplanted kidneys derived from brain dead donors have a decreased viability indicates that potential grafts are already damaged before retrieval and preservation. In this review, we present an overview of the current knowledge of (patho)-physiological effects of brain death and its relevance for renal transplant outcome. In addition, several options for therapeutic intervention during brain death in the donor with the goal to improve organ viability and transplant outcome are discussed.


Assuntos
Morte Encefálica/fisiopatologia , Transplante de Rim/tendências , Rim/fisiopatologia , Transplantes/normas , Animais , Modelos Animais de Doenças , Sobrevivência de Enxerto/fisiologia , Humanos , Coleta de Tecidos e Órgãos
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