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1.
Int J Artif Organs ; 43(1): 3-9, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31900096

RESUMO

Ex vivo testing is a fundamental step in the development of new medical devices; indeed without it, it is impossible to proceed with in vivo tests. At the University of Florence, a robotic tool for microwave thermal ablation is under development. Up to now, the thermoablation tests for the validation of the tool were carried out on non-perfused ex vivo livers, providing results that inevitably differ from those obtainable with an in vivo liver. The aim is to design, and consequently create, a compact and transportable system which allows to perfuse a swine liver with physiological solution and heparin. This device should also allow the organ to be transported from the explantation place to the laboratory, keeping it under normothermal condition. The perfusor was designed to simulate the physiological flow within the liver in the most realistic way possible. The design, construction, and optimization of the perfusor have been addressed using the physiological values of hepatic flow and pressure identified in the literature, neglecting in the first instance any load losses. Therefore, open circuit tests were conducted, validated through perfusion tests on freshly explanted pig liver; during these tests, the surface temperature of the organ was recorded using an infrared camera, and the fluid temperature was verified using an immersion probe. The perfusion test showed a good alignment with the open circuit tests, demonstrating the validity of the simplifications adopted to treat the complex vascular structure of the liver.


Assuntos
Fígado/fisiologia , Preservação de Órgãos/instrumentação , Perfusão/instrumentação , Animais , Desenho de Equipamento , Transplante de Fígado , Modelos Animais , Preservação de Órgãos/métodos , Suínos , Temperatura Ambiente
4.
JAMA ; 322(18): 1756, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31714967
5.
Nat Biotechnol ; 37(10): 1131-1136, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31501557

RESUMO

The inability to preserve vascular organs beyond several hours contributes to the scarcity of organs for transplantation1,2. Standard hypothermic preservation at +4 °C (refs. 1,3) limits liver preservation to less than 12 h. Our group previously showed that supercooled ice-free storage at -6 °C can extend viable preservation of rat livers4,5 However, scaling supercooling preservation to human organs is intrinsically limited because of volume-dependent stochastic ice formation. Here, we describe an improved supercooling protocol that averts freezing of human livers by minimizing favorable sites of ice nucleation and homogeneous preconditioning with protective agents during machine perfusion. We show that human livers can be stored at -4 °C with supercooling followed by subnormothermic machine perfusion, effectively extending the ex vivo life of the organ by 27 h. We show that viability of livers before and after supercooling is unchanged, and that after supercooling livers can withstand the stress of simulated transplantation by ex vivo normothermic reperfusion with blood.


Assuntos
Temperatura Baixa , Fígado/fisiologia , Preservação de Órgãos/métodos , Humanos , Soluções para Preservação de Órgãos , Perfusão , Sobrevivência de Tecidos
7.
Ann R Coll Surg Engl ; 101(8): 609-616, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31508984

RESUMO

INTRODUCTION: Hypothermic machine perfusion, an organ preservation modality, involves flow of chilled preservation fluid through an allograft's vasculature. This study describes a simple, reproducible, human model that allows for interrogation of flow effects during ex vivo organ perfusion. MATERIALS AND METHODS: Gonadal veins from deceased human renal allografts were subjected to either static cold storage or hypothermic machine perfusion for up to 24 hours. Caspase-3, Krüppel-like factor 2 expression and electron microscopic analysis were compared between 'flow' and 'no-flow' conditions, with living donor gonadal vein sections serving as negative controls. RESULTS: The increase in caspase-3 expression was less pronounced for hypothermic machine-perfused veins compared with static cold storage (median-fold increase 1.2 vs 2.3; P < 0.05). Transmission electron microscopy provided ultrastructural corroboration of endothelial cell apoptosis in static cold storage conditions. For static cold storage preserved veins, Krüppel-like factor 2 expression diminished in a time-dependent manner between baseline and 12 hours (P < 0.05) but was abrogated and reversed by hypothermic machine perfusion (P < 0.05). CONCLUSIONS: Our methodology is a simple, reproducible and successful model of ex vivo perfusion in the context of human organ preservation. To demonstrate the model's utility, we establish that two widely used markers of endothelial health (caspase-3 and Krüppel-like factor 2) differ between the flow and no-flow conditions of the two predominant kidney preservation modalities. These findings suggest that ex vivo perfusion may mediate the induction of a biochemically favourable endothelial niche which may contribute tohypothermic machine perfusion's association with improved renal transplantation outcomes.


Assuntos
Transplante de Rim/métodos , Rim/irrigação sanguínea , Modelos Biológicos , Soluções para Preservação de Órgãos/farmacocinética , Preservação de Órgãos/métodos , Apoptose , Biomarcadores/metabolismo , Cadáver , Caspase 3/metabolismo , Temperatura Baixa , Endotélio Vascular/metabolismo , Humanos , Rim/metabolismo , Rim/ultraestrutura , Fatores de Transcrição Kruppel-Like/metabolismo , Microscopia Eletrônica , Perfusão/métodos , Veias/metabolismo , Veias/ultraestrutura
8.
Transplant Proc ; 51(8): 2676-2682, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31477422

RESUMO

BACKGROUND: The hypothermic machine perfusion reduces delayed graft function after kidney transplant and allows, to some extent, predicting early graft function. However, it is difficult to identify exact perfusion criteria with which to exclude kidneys from transplant or modify post-transplant care. The aim of this study was to analyze whether renal resistance during the fourth hour of hypothermic machine perfusion is useful in the prediction of graft survival and acute rejection. PATIENTS AND METHODS: Data on pretransplant hypothermic machine perfusion parameters of 407 transplanted kidneys were available. Receiver operating characteristic curve analysis was performed to find an optimal cutoff value of ratio for predicting a higher risk class of considered group of patients. According to this, patients were divided into 2 groups: those who received kidneys with renal resistance lower than 0.19 mm Hg/mL/min (R1; n = 187) and those who received kidneys with renal resistance equal to or higher than 0.19 mm Hg/mL/min (R2; n = 220). Within R2, we additionally analyzed 2 subgroups: patients who received induction therapy (R2-Ind+; n = 124) and those who did not received induction therapy (R2-Ind-; n = 96). RESULTS: Acute rejection in R1 within 1 month post transplant was 2-fold lower compared with R2 and was 6.4% vs 13.1% (P = .03), respectively. One-year graft survival was higher in R1 compared with R2 and was 94.6% vs 88.5% (P = .03), respectively. Acute rejection in the R2-Ind+ subgroup within 1 month post transplant was 2.46-fold lower compared with the R2-Ind- subgroup and was 8% vs 19.7% (P = .01), respectively. CONCLUSION: Immunosuppression treatment after transplant should be adjusted to perfusion parameters.


Assuntos
Imunossupressão/métodos , Transplante de Rim , Rim/fisiopatologia , Preservação de Órgãos/métodos , Transplantes/fisiopatologia , Adulto , Função Retardada do Enxerto/fisiopatologia , Feminino , Rejeição de Enxerto/fisiopatologia , Sobrevivência de Enxerto , Humanos , Masculino , Pessoa de Meia-Idade , Perfusão
9.
Transplant Proc ; 51(8): 2514-2519, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31473005

RESUMO

BACKGROUND: Hypothermic machine perfusion (HMP) has become a standard method of preservation for kidneys procured from expanded-criteria donors and donors after cardiac death. There are different systems and approaches to the HMP preservation period, with cold storage prior to HMP sometimes taking several hours. This study evaluated whether the time at which kidneys receive HMP had any influence on the outcomes of kidney transplantation. METHODS: In this analysis, patient and graft survival were evaluated over a 1-year post-transplantation period. Patients who received HMP kidneys (n = 379) were divided into 2 groups: those who received kidneys with a cold ischemia time (CIT) prior to HMP <295 minutes (group G1; n = 254) and those who received kidneys with CIT prior to HMP >295 minutes (group G2; n = 125). RESULTS: Delayed graft function was observed in 31.8% (81/254) of patients in group G1 vs 46.4% (58/125) of patients in group G2 (P = .007). One-year graft survival was statistically higher in the group G1 (93.2%; 233/254) vs group G2 (86.5%; 105/125, P = .029). Mean 1-year estimated glomerular filtration rate was significantly better in the group G1. CONCLUSIONS: In conclusion, introduction of HMP up to 295 minutes from procurement led to better early and 1-year graft results. Kidneys should receive HMP as soon as possible after retrieval, preferably during procurement.


Assuntos
Isquemia Fria/efeitos adversos , Criopreservação/métodos , Transplante de Rim/efeitos adversos , Rim , Preservação de Órgãos/efeitos adversos , Perfusão/efeitos adversos , Adulto , Isquemia Fria/métodos , Morte , Função Retardada do Enxerto/etiologia , Feminino , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Hipotermia Induzida , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Preservação de Órgãos/métodos , Perfusão/métodos , Fatores de Tempo , Doadores de Tecidos , Resultado do Tratamento
10.
Transplant Proc ; 51(8): 2520-2522, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31395361

RESUMO

We have adopted a modified method to resuscitate kidneys from donation after circulatory death (DCD) donors with the use of Euro-Collins (EC) solution instead of University of Wisconsin solution. This study aimed to evaluate kidney transplantation (KTx) outcomes of DCD procured with low-dose in situ perfusion using EC solution. PATIENTS AND METHODS: KTx was performed in 8 adults. Kidney grafts were procured following in situ perfusion with approximately 1 L of EC solution and preserved in the solution. The kidney donor profile index value was 88% ± 21%. The terminal creatinine level of the donors was 5.5 ± 3.4 mg/dL. Of the 8 donors, 6 experienced oligoanuria prior to graft procurement. RESULTS: The mean age of the recipients and the hemodialysis vintage were 50 ± 10 years and 161 ± 25 months, respectively. The warm and cold ischemic times were 8.3 ± 7.9 minutes and 8.7 ± 4.3 hours, respectively. All grafts functioned after a delayed graft function of 10.6 ± 6.9 days (2-25 days). There was neither immediate graft function nor primary nonfunction. The patient and graft survivals were both 100% with a terminal creatinine level of 1.3 ± .5 mg/dL. CONCLUSIONS: Kidney grafts procured from DCD donors with a high kidney donor profile index value demonstrated good renal function with an excellent midterm outcome. Low-dose in situ perfusion with EC solution is effective for the procurement of marginal kidney grafts from DCD donors under optimal conditions such as a relatively shorter preservation time.


Assuntos
Sobrevivência de Enxerto , Soluções Hipertônicas/administração & dosagem , Transplante de Rim/métodos , Preservação de Órgãos/métodos , Perfusão/métodos , Adulto , Isquemia Fria , Creatinina/análise , Morte , Função Retardada do Enxerto/etiologia , Feminino , Humanos , Rim/efeitos dos fármacos , Rim/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/métodos , Transplantes/efeitos dos fármacos , Transplantes/fisiopatologia , Resultado do Tratamento , Isquemia Quente
11.
Transplant Proc ; 51(6): 1785-1790, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31399164

RESUMO

BACKGROUND: Hypothermic machine perfusion is used to improve renal perfusion and reduce the rate of early and late graft dysfunction. It has been used in our unit since 2001. It has 2 modes of flow: continuous or pulsatile. The aim of this study is to compare the modes of perfusion in terms of perfusion-related parameters, graft survival, and estimated glomerular filtration rate. METHODS: All donation after cardiac death kidneys between 2002 and 2014 were reviewed. A total of 64 pairs of kidneys were identified of which one kidney underwent pulsatile and the other continuous perfusion. Machine parameters including resistance and perfusion flow index levels at 0, 1, 2, 3, and 4 hours were recorded and glutathione S-transferase was measured in perfusate. Estimated glomerular filtration rate from the first week of transplant until the fifth year and graft survival rates were determined. RESULTS: Machine parameters were similar at all time points. Estimated glomerular filtration rates and graft survival were the same irrespective of perfusion mode. CONCLUSION: Pulsatile perfusion may be regarded as more physiological. However, we could not identify difference in outcome following transplant of kidneys from the same donor that had been perfused under pulsatile or continuous conditions.


Assuntos
Circulação Extracorpórea/métodos , Hipotermia Induzida/métodos , Preservação de Órgãos/métodos , Perfusão/métodos , Fluxo Pulsátil , Morte , Feminino , Taxa de Filtração Glomerular , Glutationa Transferase/análise , Sobrevivência de Enxerto , Humanos , Rim/irrigação sanguínea , Rim/fisiopatologia , Transplante de Rim , Masculino , Taxa de Sobrevida , Doadores de Tecidos , Transplantes/irrigação sanguínea , Transplantes/fisiopatologia , Resultado do Tratamento
13.
Mol Med Rep ; 20(2): 1663-1671, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257470

RESUMO

A limited number of studies have revealed that adding kidneys to liver perfusion may maintain an improved physiological balance; however, the underlying mechanism remains to be elucidated. The preset study confirmed the protective role of this new model and investigated the underlying mechanisms. Methods: A total of 12 rats were randomly assigned into two groups (n=6 for each group): The kidney­liver perfusion (KL) group and liver perfusion (LP) group. Perfusate samples were collected during the perfusion process for the analysis of pH, K+ and liver function. Liver tissues were obtained for the evaluation of adenosine triphosphate (ATP), terminal deoxynucleotidyl­transferase­mediated dUTP nick end labelling and immunohistochemistry of Ki67. Cell cycle inhibitors, apoptosis­associated genes and signal transducer and activator of transcription 3 (Stat3) were analyzed using quantitative polymerase chain reaction and western blot analysis. Results: Overall pH and K+ values of the KL group were significantly different from the LP group and more stable; aspartate aminotransferase, alanine transaminase and lactate dehydrogenase levels increased progressively over time in the LP group and were significantly different at different time points compared with pre­perfusion levels and the KL group, which suggested the KL group was superior to the LP group. In addition, KL reduced portal vein resistance and was associated with lower ATP consumption compared with the LP group. Furthermore, liver proliferation was upregulated with the upregulation of the interleukin 6 (IL­6)/Stat3 signaling pathway in KL compared with LP. The present study revealed for the first time that KL and hypothermic machine perfusion demonstrated a more proactive repair capability by maintaining liver regeneration via the upregulation of the IL­6/Stat3 signaling pathway.


Assuntos
Interleucina-6/metabolismo , Rim/fisiologia , Fígado/fisiologia , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Animais , Temperatura Baixa , Transplante de Fígado , Masculino , Preservação de Órgãos/métodos , Perfusão/métodos , Ratos , Ratos Sprague-Dawley
14.
Mol Med Rep ; 20(3): 2101-2110, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31257518

RESUMO

Ischemia­reperfusion injury (IRI) is a notable cause of tissue damage during surgical procedures and a major risk factor in graft dysfunction in liver transplantation. Livers obtained from donors after circulatory death (DCD) are prone to IRI and toll­like receptor 4 (TLR4) serves a prominent role in the inflammatory response associated with DCD liver IRI. The present study was designed to investigate whether TAK242, a specific TLR4 inhibitor, improves hepatic IRI following a DCD graft and to investigate its underlying protective mechanisms. Male Sprague­Dawley rats were randomized into 4 groups: Control, TAK242, DCD and DCD+TAK242 groups. Rats were pretreated with TAK242 or its vehicle for 30 min, then the livers were harvested without warm ischemia (control group and TAK242 group) or with warm ischemia in situ for 30 min. The livers were stored in cold University of Wisconsin solution for 24 h and subsequently perfused for 60 min with an isolated perfused rat liver system. Rat liver injury was evaluated thereafter. When compared with the DCD group, DCD livers with TAK242 pretreatment displayed significantly improved hepatic tissue injury and less tissue necrosis (P<0.05). Compared with DCD livers, mechanistic experiments revealed that TAK242 pretreatment alleviated mitochondrial dysfunction, reduced reactive oxygen species and malondialdehyde levels and inhibited apoptosis. Additionally, TAK242 significantly inhibited the IRI­associated inflammatory response, indicated by the decreased expression of TLR4, interleukin (IL)­1ß, IL­6 and cyclooxygenase 2 at the mRNA and protein levels (P<0.05). TAK242 ameliorates DCD liver IRI via suppressing the TLR4 signaling pathway in rats. The results of the present study have revealed that TAK242 pretreatment harbors a potential benefit for liver transplantation.


Assuntos
Anti-Inflamatórios/farmacologia , Fígado/efeitos dos fármacos , Preservação de Órgãos/métodos , Traumatismo por Reperfusão/imunologia , Sulfonamidas/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Adenosina/farmacologia , Alopurinol/farmacologia , Animais , Glutationa/farmacologia , Insulina/farmacologia , Fígado/imunologia , Fígado/patologia , Fígado/ultraestrutura , Transplante de Fígado , Masculino , Soluções para Preservação de Órgãos/farmacologia , Rafinose/farmacologia , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/imunologia , Isquemia Quente
15.
J Card Surg ; 34(10): 969-975, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31332833

RESUMO

OBJECTIVES: Cold crystalloid cardioplegia for donor heart harvesting and cold ischemic storage conditions during the transportation is the standard of care during heart transplantation procedure. Organ care system (OCS) was introduced for more prolonged and reliable ex vivo organ management. This study evaluated the two different techniques used for myocardial preservation during the procurement and transportation of the heart using the OCS. METHODS: We performed prospective analysis of 43 patients with heart failure undergoing heart transplantation and using the OCS for donor organ transport. Donor hearts were arrested using blood cardioplegia and conditioning (n = 30) or standard Custodiol (SC) solution ( n = 13). Perfusion and cardiac function parameters were continuously monitored while the donor hearts were perfused in the OCS. Impact of preservation techniques on biochemical parameters and clinical outcomes were evaluated. RESULTS: All donor hearts had stable perfusion and lactate characteristics in the OCS, with similar measures between the two groups at the beginning of the ex vivo perfusion. Ex vivo heart perfusion mean ending concentration of Interleukin (IL)-6 and IL-8 was significantly lower in the blood cardioplegia group compared to the standard care group. Clinical outcomes were comparable between the two groups of patients. CONCLUSIONS: The use of blood cardioplegia and conditioning could be a safe method for myocardial protection in distant procurement and preservation of donor hearts in the OCS.


Assuntos
Parada Cardíaca Induzida/métodos , Insuficiência Cardíaca/cirurgia , Transplante de Coração/métodos , Preservação de Órgãos/métodos , Perfusão/métodos , Doadores de Tecidos , Adulto , Feminino , Seguimentos , Glucose/farmacologia , Humanos , Masculino , Manitol/farmacologia , Soluções para Preservação de Órgãos/farmacologia , Cloreto de Potássio/farmacologia , Procaína/farmacologia , Estudos Prospectivos
16.
Cornea ; 38(10): 1314-1321, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31335527

RESUMO

PURPOSE: To evaluate a new corneal cold storage medium including an antimycotic tablet (Kerasave, AL.CHI.MI.A. S.r.l.). METHODS: Kerasave and tryptone soy broth (control) were inoculated with 10 and 10 colony-forming units (CFU)/mL of 6 Candida isolates (Candida albicans [n = 4], Candida tropicalis [n = 1], and Candida glabrata [n = 1]). Minimum inhibitory concentrations (MICs) were determined using amphotericin B Etest strips. Sterile porcine corneas contaminated with 10 CFU/mL of each isolate were incubated in Kerasave and control at 4°C. Growth rate and Log10 reduction at 4°C at different time intervals were determined for liquid samples and tissue homogenates. Kerasave biocompatibility was assessed according to ISO 10993-5 and ISO 10993-10. RESULTS: No C. albicans or C. tropicalis colonies were recovered from Kerasave inoculated with 10 CFU/mL after incubation for 3 days at 4°C. C. glabrata was inhibited but not killed after 3 days at 4°C. Four of the 6 strains contaminated with 10 CFU/mL demonstrated a significant ≥ 3 Log10 reduction in media and tissue homogenates within 5 days as compared to controls (p < 0.01). Amphotericin B MICs ranged from 0.19 to 0.38 µg/mL for C. albicans (n = 3) and C. tropicalis (n = 1). C. glabrata showed reduced susceptibility (0.5 µg/mL) and 1 C. albicans was resistant to amphotericin B (≥ 1 µg/mL). Kerasave was not cytotoxic, irritating, or sensitizing according to the ISO standards. CONCLUSIONS: Kerasave showed high antifungal efficacy against susceptible fungal strains at 4°C in the presence and absence of corneal tissue. Resistant strains to amphotericin B were not eliminated by Kerasave. Kerasave is not cytotoxic, irritating, or sensitizing.


Assuntos
Anfotericina B/farmacologia , Candida/efeitos dos fármacos , Candidíase/tratamento farmacológico , Córnea/efeitos dos fármacos , Infecções Oculares Fúngicas/tratamento farmacológico , Ceratite/tratamento farmacológico , Soluções para Preservação de Órgãos/farmacologia , Animais , Antifúngicos/farmacologia , Candida/isolamento & purificação , Candidíase/diagnóstico , Candidíase/microbiologia , Córnea/diagnóstico por imagem , Modelos Animais de Doenças , Infecções Oculares Fúngicas/diagnóstico , Infecções Oculares Fúngicas/microbiologia , Ceratite/diagnóstico , Ceratite/microbiologia , Testes de Sensibilidade Microbiana , Preservação de Órgãos/métodos , Suínos
17.
Einstein (Sao Paulo) ; 17(4): eAO4288, 2019 Jul 15.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31314859

RESUMO

OBJECTIVE: To assess the feasibility and impact of ex vivo lung perfusion with hyperoncotic solution (Steen Solution™) in the utilization of these organs in Brazil. METHODS: In this prospective study, we subjected five lungs considered to be high risk for transplantation to 4 hours of ex vivo lung perfusion, with evaluation of oxygenation capacity. High-risk donor lungs were defined by specific criteria, including inflammatory infiltrates, pulmonary edema and partial pressure of arterial oxygen less than 300mmHg (inspired oxygen fraction of 100%). RESULTS: During reperfusion, the mean partial pressure of arterial oxygen (inspired oxygen fraction of 100%) of the lungs did not change significantly (p=0.315). In the first hour, the mean partial pressure of arterial oxygen was 302.7mmHg (±127.66mmHg); in the second hour, 214.2mmHg (±94.12mmHg); in the third hour, 214.4mmHg (±99.70mmHg); and in the fourth hour, 217.7mmHg (±73.93mmHg). Plasma levels of lactate and glucose remained stable during perfusion, with no statistical difference between the moments studied (p=0.216). CONCLUSION: Ex vivo lung perfusion was reproduced in our center and ensured the preservation of lungs during the study period, which was 4 hours. The technique did not provide enough improvement for indicating organs for transplantation; therefore, it did not impact on use of these organs.


Assuntos
Transplante de Pulmão/métodos , Preservação de Órgãos/métodos , Perfusão/métodos , Doadores de Tecidos , Adulto , Brasil , Estudos Transversais , Seleção do Doador , Feminino , Humanos , Pulmão/irrigação sanguínea , Complacência Pulmonar , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
18.
Int J Mol Sci ; 20(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340593

RESUMO

Normothermic machine perfusion (NMP) of kidneys offers the opportunity to perform active interventions, such as the addition of mesenchymal stromal cells (MSCs), to an isolated organ prior to transplantation. The purpose of this study was to determine whether administering MSCs to kidneys during NMP is feasible, what the effect of NMP is on MSCs and whether intact MSCs are retained in the kidney and to which structures they home. Viable porcine kidneys were obtained from a slaughterhouse. Kidneys were machine perfused during 7 h at 37 °C. After 1 h of perfusion either 0, 105, 106 or 107 human adipose tissue derived MSCs were added. Additional ex vivo perfusions were conducted with fluorescent pre-labelled bone-marrow derived MSCs to assess localisation and survival of MSCs during NMP. After NMP, intact MSCs were detected by immunohistochemistry in the lumen of glomerular capillaries, but only in the 107 MSC group. The experiments with fluorescent pre-labelled MSCs showed that only a minority of glomeruli were positive for infused MSCs and most of these glomeruli contained multiple MSCs. Flow cytometry showed that the number of infused MSCs in the perfusion circuit steeply declined during NMP to approximately 10%. In conclusion, the number of circulating MSCs in the perfusate decreases rapidly in time and after NMP only a small portion of the MSCs are intact and these appear to be clustered in a minority of glomeruli.


Assuntos
Rastreamento de Células/métodos , Glomérulos Renais/ultraestrutura , Transplante de Rim , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Perfusão/métodos , Adipócitos/citologia , Adipócitos/fisiologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/fisiologia , Diferenciação Celular , Corantes Fluorescentes/metabolismo , Humanos , Glomérulos Renais/cirurgia , Transplante de Células-Tronco Mesenquimais/instrumentação , Células-Tronco Mesenquimais/fisiologia , Microscopia de Fluorescência , Preservação de Órgãos/métodos , Compostos Orgânicos/metabolismo , Perfusão/instrumentação , Suínos , Temperatura Ambiente , Transplante Heterólogo
19.
Transplant Proc ; 51(6): 1926-1933, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31301856

RESUMO

BACKGROUND: Surgical factors and direct cytotoxicity of bile salts on cholangiocytes may play a role in the development of ischemic cholangiopathy (IC) after liver transplantation (LTx). There is no validated consensus on how to protect the bile ducts during procurement, static preservation, and LTx. Meanwhile, IC remains the most troublesome complication after LTx. AIM: To characterize bile duct management techniques during the LTx process among European transplant centers in cases of donation after brain death (DBD) and circulatory death (DCD). METHOD: An European Liver and Intestine Transplant Association-European Liver Transplant Registry web survey designed to conceal respondents' personal information was sent to surgeons procuring and/or transplanting livers in Europe. RESULTS: Sixty-five percent of responses came from large transplant centers (>50 procurements/y). In 8% of DBDs and 14% of DCDs the bile duct is not rinsed. In 46% of DBDs and 52% of DCDs surgeons prefer to remove the gallbladder after graft reperfusion. Protocols concerning preservation solutions (nature, pressure, volume) are extremely heterogeneous. In 54% of DBDs and 61% of DCDs an arterial back table pressure perfusion is performed. Steroids (20%-10%), heparin (72%-60%), prostacyclin (3%-7%), and fibrinolytics (4%-11%) are used as donor-protective interventions in DBD and DCD cases, respectively. In 2% of DBD and 6% of DCD cases a hepatic artery reperfusion is performed first. In 4% of DBD and 6% of DCD cases, fibrinolytics are administered through the hepatic artery during the bench and/or implantation. CONCLUSION: This European web survey shows for the first time the heterogeneity in the management of bile ducts during procurement, preservation, and transplantation in Europe. In the context of sharing more marginal liver grafts, an expert meeting must be organized to formulate guidelines to be applied to protect liver grafts against IC.


Assuntos
Ductos Biliares/irrigação sanguínea , Colangite/etiologia , Isquemia/etiologia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/etiologia , Coleta de Tecidos e Órgãos/efeitos adversos , Ductos Biliares/transplante , Europa (Continente) , Feminino , Sobrevivência de Enxerto , Humanos , Masculino , Preservação de Órgãos/efeitos adversos , Preservação de Órgãos/métodos , Perfusão/efeitos adversos , Perfusão/métodos , Reperfusão/efeitos adversos , Reperfusão/métodos , Inquéritos e Questionários , Coleta de Tecidos e Órgãos/métodos
20.
Int J Artif Organs ; 42(7): 362-369, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31238824

RESUMO

OBJECTIVE: Ex-vivo lung perfusion is a promising tool to evaluate and recondition marginal donor lungs usually after a cold static preservation. The concept of continuous organ perfusion is supposed to reduce ischemic damage; however, the optimal perfusion protocol has not been established yet. The aim of this study was to compare immediate ex-vivo lung perfusion (I-EVLP) to delayed ex-vivo lung perfusion (D-EVLP) after a certain cold static preservation period on lung function in a large animal model. METHODS: In a porcine model, lungs were procured after circulatory death and 60 min of no-touch warm ischemia. Lungs were preserved with single-flush cold low potassium dextran solution and prepared either for I-EVLP (n = 8) or stored cold for 9 h with subsequent D-EVLP (n = 8). Functional outcomes and morphology were compared during 4 h of ex-vivo lung perfusion, using STEEN SolutionTM as perfusion solution. RESULTS: Pulmonary functional data, perfusate activities of lactate dehydrogenase, alkaline phosphatase, and products of lipid peroxidation did not differ significantly. There was a trend toward lower wet-dry ratio (I-EVLP: 13.4 ± 2.9; D-EVLP: 9.1 ± 2.5) and higher ΔpO2 in D-EVLP group (I-EVLP: 209 ± 51.6 mmHg; D-EVLP: 236.3 ± 47.3 mmHg). CONCLUSION: In this donation-after-circulatory-death model, 9 h of cold static preservation followed by ex-vivo lung perfusion results in comparable pulmonary function to I-EVLP as indicated by oxygenation capacities and wet-dry ratio. Our findings indicate that prolonged cold static preservation prior to ex-vivo lung perfusion is as safe and effective as I-EVLP in the procurement of donor lungs.


Assuntos
Circulação Extracorpórea/métodos , Parada Cardíaca/cirurgia , Transplante de Pulmão/métodos , Preservação de Órgãos/métodos , Animais , Modelos Animais de Doenças , Suínos , Fatores de Tempo , Isquemia Quente
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