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1.
Biomed Pharmacother ; 173: 116262, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38394845

RESUMO

BACKGROUND: The glucose derivative 3-O-methyl-D-glucose (OMG) is used as a cryoprotectant in freezing cells. However, its protective role and the related mechanism in static cold storage (CS) of organs are unknown. The present study aimed to investigate the effect of OMG on cod ischemia damage in cold preservation of donor kidney. METHODS: Pretreatment of OMG on kidney was performed in an isolated renal cold storage model in rats. LDH activity in renal efflux was used to evaluate the cellular damage. Indicators including iron levels, mitochondrial damage, MDA level, and cellular apoptosis were measured. Kidney quality was assessed via a kidney transplantation (KTx) model in rats. The grafted animals were followed up for 7 days. Ischemia reperfusion (I/R) injury and inflammatory response were assessed by biochemical and histological analyses. RESULTS: OMG pretreatment alleviated prolonged CS-induced renal damage as evidenced by reduced LDH activities and tubular apoptosis. Kidney with pCS has significantly increased iron, MDA, and TUNEL+ cells, implying the increased ferroptosis, which has been partly inhibited by OMG. OMG pretreatment has improved the renal function (p <0.05) and prolonged the 7-day survival of the grafting recipients after KTx, as compared to the control group. OMG has significantly decreased inflammation and tubular damage after KTx, as evidenced by CD3-positive cells and TUNEL-positive cells. CONCLUSION: Our study demonstrated that OMG protected kidney against the prolonged cold ischemia-caused injuries through inhibiting ferroptosis. Our results suggested that OMG might have potential clinical application in cold preservation of donor kidney.


Assuntos
Ferroptose , Traumatismo por Reperfusão , Ratos , Animais , 3-O-Metilglucose/farmacologia , Isquemia Fria/efeitos adversos , Preservação de Órgãos/métodos , Rim , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/patologia , Isquemia/patologia , Ferro
2.
Clin Transplant ; 38(1): e15201, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38041480

RESUMO

BACKGROUND: We aimed to cluster deceased donor kidney transplant recipients with prolonged cold ischemia time (CIT) using an unsupervised machine learning approach. METHODS: We performed consensus cluster analysis on 11 615 deceased donor kidney transplant patients with CIT exceeding 24 h using OPTN/UNOS data from 2015 to 2019. Cluster characteristics of clinical significance were identified, and post-transplant outcomes were compared. RESULTS: Consensus cluster analysis identified two clinically distinct clusters. Cluster 1 was characterized by young, non-diabetic patients who received kidney transplants from young, non-hypertensive, non-ECD deceased donors with lower KDPI scores. In contrast, the patients in cluster 2 were older and more likely to have diabetes. Cluster 2 recipients were more likely to receive transplants from older donors with a higher KDPI. There was lower use of machine perfusion in Cluster 1 and incrementally longer CIT in Cluster 2. Cluster 2 had a higher incidence of delayed graft function (42% vs. 29%), and lower 1-year patient (95% vs. 98%) and death-censored (95% vs. 97%) graft survival compared to Cluster 1. CONCLUSIONS: Unsupervised machine learning characterized deceased donor kidney transplant recipients with prolonged CIT into two clusters with differing outcomes. Although Cluster 1 had more favorable recipient and donor characteristics and better survival, the outcomes observed in Cluster 2 were also satisfactory. Overall, both clusters demonstrated good survival suggesting opportunities for transplant centers to incrementally increase CIT.


Assuntos
Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Função Retardada do Enxerto/etiologia , Rejeição de Enxerto , Isquemia Fria/efeitos adversos , Consenso , Sobrevivência de Enxerto , Doadores de Tecidos , Análise por Conglomerados , Aprendizado de Máquina
3.
J Proteome Res ; 23(1): 483-493, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38109371

RESUMO

Proton magnetic resonance spectroscopy (1H-MRS) of surgically collected tumor specimens may contribute to investigating cancer metabolism and the significance of the "total choline" (tCho) peak (3.2 ppm) as malignancy and therapy response biomarker. To ensure preservation of intrinsic metabolomic information, standardized handling procedures are needed. The effects of time to freeze (cold ischemia) were evaluated in (a) surgical epithelial ovarian cancer (EOC) specimens using high-resolution (HR) 1H-MRS (9.4 T) of aqueous extracts and (b) preclinical EOC samples (xenografts in SCID mice) investigated by in vivo MRI-guided 1H-MRS (4.7 T) and by HR-1H-MRS (9.4 T) of tumor extracts or intact fragments (using magic-angle-spinning (MAS) technology). No significant changes were found in the levels of 27 of 29 MRS-detected metabolites (including the tCho profile) in clinical specimens up to 2 h cold ischemia, besides an increase in lysine and a decrease in glutathione. EOC xenografts showed a 2-fold increase in free choline within 2 h cold ischemia, without further significant changes for any MRS-detected metabolite (including phosphocholine and tCho) up to 6 h. At shorter times (≤1 h), HR-MAS analyses showed unaltered tCho components, along with significant changes in lactate, glutamate, and glutamine. Our results support the view that a time to freeze of 1 h represents a safe threshold to ensure the maintenance of a reliable tCho profile in EOC specimens.


Assuntos
Isquemia Fria , Neoplasias Ovarianas , Camundongos , Animais , Humanos , Feminino , Espectroscopia de Ressonância Magnética/métodos , Camundongos SCID , Metaboloma , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/metabolismo , Colina/metabolismo
4.
BMC Pulm Med ; 23(1): 213, 2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37330482

RESUMO

BACKGROUND: Mitochondrial dysfunction results in poor organ quality, negatively affecting the outcomes of lung transplantation. Whether hydrogen benefits mitochondrial function in cold-preserved donors remain unclear. The present study assessed the effect of hydrogen on mitochondrial dysfunction in donor lung injury during cold ischemia phase (CIP) and explored the underlying regulatory mechanism. METHODS: Left donor lungs were inflated using 40% oxygen + 60% nitrogen (O group), or 3% hydrogen + 40% oxygen + 57% nitrogen (H group). Donor lungs were deflated in the control group and were harvested immediately after perfusion in the sham group (n = 10). Inflammation, oxidative stress, apoptosis, histological changes, mitochondrial energy metabolism, and mitochondrial structure and function were assessed. The expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were also analyzed. RESULTS: Compared with the sham group, inflammatory response, oxidative stress, histopathological changes, and mitochondrial damage were severe in the other three groups. However, these injury indexes were remarkably decreased in O and H groups, with increased Nrf2 and HO-1 levels, elevated mitochondrial biosynthesis, inhibition of anaerobic glycolysis and restored mitochondrial structure and function compared with the control group. Moreover, inflation using hydrogen contributed to stronger protection against mitochondrial dysfunction and higher levels of Nrf2 and HO-1 when comparing with O group. CONCLUSIONS: Lung inflation using hydrogen during CIP may improve donor lung quality by mitigating mitochondrial structural anomalies, enhancing mitochondrial function, and alleviating oxidative stress, inflammation, and apoptosis, which may be achieved through activation of the Nrf2/HO-1 pathway.


Assuntos
Isquemia Fria , Traumatismo por Reperfusão , Humanos , Isquemia Fria/métodos , Hidrogênio/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Pulmão/patologia , Estresse Oxidativo , Heme Oxigenase-1 , Oxigênio/metabolismo , Apoptose , Inflamação/metabolismo
5.
Mod Pathol ; 36(9): 100220, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37230414

RESUMO

Programmed cell death ligand-1 (PD-L1) expression levels in patients' tumors have demonstrated clinical utility across many cancer types and are used to determine treatment eligibility. Several independently developed PD-L1 immunohistochemical (IHC) predictive assays are commercially available and have demonstrated different levels of staining between assays, generating interest in understanding the similarities and differences between assays. Previously, we identified epitopes in the internal and external domains of PD-L1, bound by antibodies in routine clinical use (SP263, SP142, 22C3, and 28-8). Variance in performance of assays utilizing these antibodies, observed following exposure to preanalytical factors such as decalcification, cold ischemia, and duration of fixation, encouraged additional investigation of antibody-binding sites, to understand whether binding site structures/conformations contribute to differential PD-L1 IHC assay staining. We proceeded to further investigate the epitopes on PD-L1 bound by these antibodies, alongside the major clones utilized in laboratory-developed tests (E1L3N, QR1, and 73-10). Characterization of QR1 and 73-10 clones demonstrated that both bind the PD-L1 C-terminal internal domain, similar to SP263/SP142. Our results also demonstrate that under suboptimal decalcification or fixation conditions, the performance of internal domain antibodies is less detrimentally affected than that of external domain antibodies 22C3/28-8. Furthermore, we show that the binding sites of external domain antibodies are susceptible to deglycosylation and conformational structural changes, which directly result in IHC staining reduction or loss. The binding sites of internal domain antibodies were unaffected by deglycosylation or conformational structural change. This study demonstrates that the location and conformation of binding sites, recognized by antibodies employed in PD-L1 diagnostic assays, differ significantly and exhibit differing degrees of robustness. These findings should reinforce the need for vigilance when performing clinical testing with different PD-L1 IHC assays, particularly in the control of cold ischemia and the selection of fixation and decalcification conditions.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Imuno-Histoquímica , Epitopos/uso terapêutico , Antígeno B7-H1/metabolismo , Isquemia Fria , Ligantes , Anticorpos , Células Clonais/patologia , Apoptose , Biomarcadores Tumorais/metabolismo
6.
Prog Transplant ; 33(2): 168-174, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37013356

RESUMO

INTRODUCTION: Liver acceptance patterns vary significantly between transplant centers. Data pertaining to outcomes of livers declined by local and regional centers and allocated nationally remains limited. PROJECT AIM: The objective was to compare post-liver transplant outcomes between liver allografts transplanted as a result of national and local-regional allocation. DESIGN: This was a retrospective evaluation of 109 nationally allocated liver allografts used for transplant by a single center. Outcomes of nationally allocated grafts were compared to standard allocation grafts (N = 505) during the same period. RESULTS: Recipients of nationally allocated grafts had lower model for end stage liver disease scores (17 vs 22, P = .001). Nationally allocated grafts were more likely to be post-cross clamp offers (29.4% vs 13.4%, P = .001) and have longer cold ischemia times (median hours 7.8 vs 5.5, P = .001). Early allograft dysfunction was common (54.1% vs 52.5%, P = .75) and did not impact hospital length of stay (median 5 vs 6 days, P = .89). There were no differences in biliary complications (P = .11). There were no differences in patient (P = .88) or graft survival (P = .35). In a multivariate model, after accounting for differences in cold ischemia time and posttransplant biliary complications, nationally allocated grafts were not associated with increased risk for graft loss (HR 0.9, 95% CI 0.4-1.8). Abnormal liver biopsy findings (33.0%) followed by donor donation after circulatory death status (22.9%) were the most common reasons for decline by local-regional centers. CONCLUSION: Despite longer cold ischemia times, patient and graft survival outcomes remain excellent and comparable to those seen from standard allocation grafts.


Assuntos
Doença Hepática Terminal , Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Isquemia Fria , Doença Hepática Terminal/cirurgia , Doença Hepática Terminal/etiologia , Estudos Retrospectivos , Índice de Gravidade de Doença , Doadores de Tecidos , Sobrevivência de Enxerto
7.
Cir. Esp. (Ed. impr.) ; 101(4): 283-286, abr. 2023. ilus
Artigo em Inglês | IBECS | ID: ibc-218928

RESUMO

Donor lung preservation at 10 °C appears to be an innovative and promising method that may improve transplant logistics by extending the cold ischemia time with excellent outcomes. We report the case of two lung transplants from two different donors involving the use of two different preservation methods, highlighting the benefits of using 10 °C lung storage. (AU)


La preservación pulmonar a 10 °C es una estrategia innovadora que podría mejorar la logística del trasplante pulmonar permitiendo prolongar el tiempo de isquemia fría de los injertos pulmonares con excelentes resultados. Presentamos el caso de dos trasplantes pulmonares de dos donantes diferentes empleando dos métodos de preservación distintos, recalcando los beneficios de utilizar este novedoso método de preservación a 10 °C. (AU)


Assuntos
Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Transplante de Pulmão , Pulmão/cirurgia , Isquemia Fria , Doadores de Tecidos , Preservação de Órgãos
9.
HPB (Oxford) ; 25(5): 543-555, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36858919

RESUMO

BACKGROUND: Split liver transplantation permits the transplant of two recipients using a single donor liver. Liver splitting can be performed using the ex-vivo technique (more convenient), or the in-situ technique (shorter cold ischaemic time). We aimed to develop a technique for liver splitting during normothermic machine perfusion which combines the advantages of both techniques and permits graft assessment prior to transplant. METHODS: Human livers declined for transplantation were perfused at 36 °C using a modified-commercial perfusion machine. We developed a six-step method to split whole livers into left lateral segment grafts and extended right grafts. Both partial livers were then perfused on separate machines for individual assessment. RESULTS: Using our technique, 10 whole livers were successfully split during normothermic perfusion resulting in 20 partial grafts. Apart from a single graft which failed due to a technical error, all grafts survived for 24-h after splitting. Survival was demonstrated by lactate clearance, bile production and synthesis of coagulation factors. CONCLUSIONS: Liver splitting during normothermic machine perfusion has the potential to revolutionise split liver transplantation. We describe a novel technique that reliably achieves two grafts from a single donor liver. This raises the possibility of semi-elective transplantation, and sophisticated graft assessment prior to implant.


Assuntos
Transplante de Fígado , Humanos , Transplante de Fígado/métodos , Doadores Vivos , Fígado/cirurgia , Isquemia Fria/métodos , Perfusão/métodos
11.
Transplantation ; 107(9): 1945-1954, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-36648297

RESUMO

BACKGROUND: Necroptosis, one of the types of regulated necrosis, causes ischemia-reperfusion (IR) lung injury. N-acetyl-leucyl-leucyl-norleucinal (ALLN), a calpain inhibitor, is known to attenuate necroptosis and apoptosis, and the purpose of this study was to evaluate the protective effect of ALLN during cold ischemia against IR injury in a rat lung transplant model. METHODS: Male Lewis rats (250-350 g) were divided into 3 groups: sham group (n = 4), nontransplantation; control group (n = 8), transplantation with IR lung injury; and ALLN group (n = 8), transplantation with IR lung injury/ALLN. Rats in the sham group underwent a simple thoracotomy, and the remaining 2 groups of rats underwent an orthotopic left lung transplant. Cold ischemic time was 15 h. After 2 h of reperfusion, physiological function, inflammatory cytokine expression, pathway activation, and the degrees of necroptosis and apoptosis were evaluated. RESULTS: Lung gas exchange (PaO 2 /FiO 2 ) was significantly better, and pulmonary edema was significantly improved in the ALLN group compared with the control group ( P = 0.0009, P = 0.0014). Plasma expression of interleukin-1ß was significantly lower in the ALLN group than in the control group ( P = 0.0313). The proportion of necroptotic and apoptotic cells was significantly lower in the ALLN group than in the control group ( P = 0.0009), whereas the proportion of apoptotic cells remained unchanged ( P = 0.372); therefore, the calpain inhibitor was thought to suppress necroptosis. CONCLUSIONS: The administration of ALLN during cold ischemia appears to improve IR lung injury in a lung transplant animal model via the inhibition of necroptosis.


Assuntos
Lesão Pulmonar , Transplante de Pulmão , Traumatismo por Reperfusão , Masculino , Ratos , Animais , Isquemia Fria/efeitos adversos , Calpaína/metabolismo , Calpaína/farmacologia , Lesão Pulmonar/metabolismo , Ratos Endogâmicos Lew , Transplante de Pulmão/efeitos adversos , Pulmão/metabolismo , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo
12.
Clin Transplant ; 37(4): e14918, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36693223

RESUMO

Donation after circulatory death (DCD) kidneys are exposed to warm ischemia, which, coupled with cold ischemia time (CIT) exacerbates delayed graft function (DGF) and is possibly associated with worse graft survival. To analyze the risk of CIT-induced DGF on DCD kidney outcomes, we evaluated national data between 2008 and 2018 of adult kidney-only recipients of paired DCD kidneys where one kidney recipient experienced DGF and the other did not. Of 5602 paired DCD kidney recipients, multivariate analysis between recipients with higher CIT relative to lower CIT showed that increasing CIT differences had a significant dose-dependent effect on overall graft survival. The graft survival risk was minimal with CIT differences of ≥1-h (adjusted hazard ratio [aHR] 1.07, 95% CI .95- 1.20, n = 5602) and ≥5-h (aHR 1.09, 95% CI .93-1.29, n = 2710) and became significant at CIT differences of ≥10-h (aHR 1.37, 95% CI 1.05-1.78, n = 1086) and ≥15-h (aHR 1.78, 95% CI 1.15-2.77, n = 1086). Between each of the four delta-CIT levels of shorter and longer CIT, there were no statistically significant differences in the proportion of acute rejection. These results suggest that in the setting of DCD kidney transplantation (KTX), DGF, specifically mediated by prolonged CIT, impacts long-term graft outcomes.


Assuntos
Função Retardada do Enxerto , Rejeição de Enxerto , Adulto , Humanos , Rejeição de Enxerto/etiologia , Isquemia Fria/efeitos adversos , Rim , Sobrevivência de Enxerto , Doadores de Tecidos , Fatores de Risco
13.
Biochem Biophys Res Commun ; 646: 96-102, 2023 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-36708596

RESUMO

With rapid development of liver transplantation technology, the demand for transplants have reached beyond the supply of organs, and thus development of effective strategies to reduce cold ischemia injury in fatty liver is important. Here, we explored the potential effect of SGLT-2 inhibitor in cold ischemia injury, fatty livers from 2 weeks methionine and choline deficient diet (MCD) rats were administered. After one week of intragastric administration of Sodium-dependent glucose transporters (SGLT-2) inhibitor empagliflozin (EMPA) or NaCI, liver were stored for 24 h. The results showed that EMPA could significantly reduce the cold ischemic injury in the mitochondria of fatty liver. To explore the mechanism, signal transducers and activators of transcription 3(STAT3) inhibitor AG490 group was used in a similar manner. We detected the changes in p-signal transducers and activators of transcription 3 (P-STAT3), alcohol-dehydrogenase 2 (ALDH2) and degree of apoptosis in three distinct groups. The results suggested that the protein expression of P-STAT3 and ALDH2 was higher in the EMPA group than in other two groups, whereas extent of apoptosis in the EMPA group was lower than other two groups. The data suggested that SGLT2 inhibitors could alleviate cold ischemia damage of mitochondria in fatty liver, which may be related to the inhibition of apoptosis and the activation of P-STAT3 and ALDH2.


Assuntos
Isquemia Fria , Fígado Gorduroso , Animais , Ratos , Fígado Gorduroso/metabolismo , Isquemia , Fígado/metabolismo , Transportador 2 de Glucose-Sódio
14.
Ann Surg ; 277(1): 144-150, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34171875

RESUMO

OBJECTIVE: To define technically Diff-LT. SUMMARY OF BACKGROUND DATA: Currently, there is no acknowledged definition of Diff-LT. METHODS: This retrospective study included all first consecutive liver-only transplantations performed in 2 centers from 2011 to 2015. Diff-LT was defined as the combination of the number of blood units transfused, cold ischemia time, and duration of operation, all at or above the median value of the entire population. The correlation of Diff-LT with short- (including the comprehensive complication index) and long-term outcomes was assessed. Outcomes were also compared to the 90-day benchmark cutoffs of LT. Predictors of Diff-LT were identified by multivariable analysis, first using only recipient data and then using all recipient, donor, graft, and surgical data. RESULTS: The study population included 467 patients. The incidence of Diff- LT was 18.8%. Diff-LT was associated with short-term outcomes, including the comprehensive complication index and mortality, but not with patient or graft long-term survival. Previous abdominal surgery, intensive care unitbound at the time of LT, split graft use, nonstandard arterial reconstruction, and porto-systemic shunt ligation were independent predictors of Diff-LT. The proportion of variables below the corresponding LT 90-day benchmark cutoffs was 8/13 (61.5%) for non-Diff-LT, and 4/13 (30.8%) for Diff-LT. CONCLUSIONS: Diff-LT, as defined, occurred frequently. Adjusting modifiable variables might decrease the risk of Diff-LT and improve the postoperative course. This definition of Diff-LT might be useful for patient information, comparison between centers and surgeons, and as a metric in future trials.


Assuntos
Transplante de Fígado , Humanos , Estudos Retrospectivos , Doadores de Tecidos , Isquemia Fria , Fatores de Tempo , Sobrevivência de Enxerto
15.
J Reconstr Microsurg ; 39(5): 350-360, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35764315

RESUMO

BACKGROUND: For 50 years, static cold storage (SCS) has been the gold standard for solid organ preservation in transplantation. Although logistically convenient, this preservation method presents important constraints in terms of duration and cold ischemia-induced lesions. We aimed to develop a machine perfusion (MP) protocol for recovery of vascularized composite allografts (VCA) after static cold preservation and determine its effects in a rat limb transplantation model. METHODS: Partial hindlimbs were procured from Lewis rats and subjected to SCS in Histidine-Tryptophan-Ketoglutarate solution for 0, 12, 18, 24, and 48 hours. They were then either transplanted (Txp), subjected to subnormothermic machine perfusion (SNMP) for 3 hours with a modified Steen solution, or to SNMP + Txp. Perfusion parameters were assessed for blood gas and electrolytes measurement, and flow rate and arterial pressures were monitored continuously. Histology was assessed at the end of perfusion. For select SCS durations, graft survival and clinical outcomes after transplantation were compared between groups at 21 days. RESULTS: Transplantation of limbs preserved for 0, 12, 18, and 24-hour SCS resulted in similar survival rates at postoperative day 21. Grafts cold-stored for 48 hours presented delayed graft failure (p = 0.0032). SNMP of limbs after 12-hour SCS recovered the vascular resistance, potassium, and lactate levels to values similar to limbs that were not subjected to SCS. However, 18-hour SCS grafts developed significant edema during SNMP recovery. Transplantation of grafts that had undergone a mixed preservation method (12-hour SCS + SNMP + Txp) resulted in better clinical outcomes based on skin clinical scores at day 21 post-transplantation when compared to the SCS + Txp group (p = 0.01613). CONCLUSION: To date, VCA MP is still limited to animal models and no protocols are yet developed for graft recovery. Our study suggests that ex vivo SNMP could help increase the preservation duration and limit cold ischemia-induced injury in VCA transplantation.


Assuntos
Transplante de Fígado , Preservação de Órgãos , Animais , Ratos , Ratos Endogâmicos Lew , Preservação de Órgãos/métodos , Perfusão/métodos , Transplante de Fígado/métodos , Isquemia Fria
16.
Mil Med ; 188(9-10): 2960-2968, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-36308325

RESUMO

BACKGROUND: Vascularized composite allotransplantation (VCA) is a restorative surgical procedure to treat whole or partially disfiguring craniofacial or limb injuries. The routine clinical use of this VCA surgery is limited using compromised allografts from deceased donors and by the failure of the current hypothermic preservation protocols to extend the allograft's cold ischemia time beyond 4 h. We hypothesized that the active replenishment of the cellular cytosolic adenosine-5`-triphosphate (ATP) stores by means of energy delivery vehicles (ATPv) encapsulating high-energy ATP is a better strategy to improve allograft's tolerance to extended cold ischemia times. MATERIALS AND METHODS: We utilized established rat model of isolated bilateral in-situ non-cycled perfusions of both hind limbs. Ipsilateral and contralateral limbs in the anesthetized animal were randomized for simultaneous perfusions with either the University of Wisconsin (UW) solution, with/without O2 supplementation (control), or with the UW solution supplemented with the ATPv, with/without O2 supplementation (experimental). Following perfusion, the hind limbs were surgically removed and stored at 4°C for 12, 16, or 24 hours as extended cold ischemia times. At the end of each respective storage time, samples of skin, and soleus, extensor digitalis longus, and tibialis anterior muscles were recovered for assessment using tissue histology and tissue lysate studies. RESULTS: Control muscle sections showed remarkable microvascular and muscle damage associated with loss of myocyte transverse striation and marked decrease in myocyte nucleus density. A total of 1,496 nuclei were counted in 179 sections of UW-perfused control muscles in contrast to 1,783 counted in 130 sections of paired experimental muscles perfused with the ATPv-enhanced perfusate. This yielded 8 and 13 nuclei/field for the control and experimental muscles, respectively (P < .004). Oxygenation of the perfusion solutions before use did not improve the nucleus density of either the control or experimental muscles (n = 7 animals, P > .05). Total protein isolated from the muscle lysates was similar in magnitude regardless of muscle type, perfusion protocol, or duration of cold ischemia time. Prolonged static cold preservation of the hind limbs completely degraded the composite tissue's Ribonucleic acid (RNA). This supplementary result confirms the notion that that reverse transcription-Polymerase Chain Reaction, enzyme-linked immunosorbent assay, or the respiratory complex II enzyme activity techniques should not be used as indices of graft quality after prolonged static cold storage. CONCLUSIONS: In conclusion, this study demonstrates that active cellular cytosolic ATP replenishment increases hind limb composite tissue tolerance to extended cold ischemia times. Quality indicators and clinically relevant biomarkers that define composite tissue viability and function during static cold storage are warranted.


Assuntos
Isquemia Fria , Soluções para Preservação de Órgãos , Ratos , Animais , Preservação de Órgãos/métodos , Trifosfato de Adenosina/metabolismo , Temperatura Baixa
17.
EBioMedicine ; 87: 104419, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36543018

RESUMO

BACKGROUND: Innate immunity plays a fundamental role in solid organ transplantation. Myeloid cells can sense danger signals or DAMPs released after tissue or cell damage, such as during ischemia processes. This study aimed to identify DAMPs released during cold ischemia storage of human liver and analyze their ability to activate the inflammasome in myeloid cells and the possible implications in terms of short-term outcomes of liver transplantation. METHODS: 79 samples of organ preservation solution (OPS) from 79 deceased donors were collected after cold static storage. We used different analytical methods to measure DAMPs in these end-ischemic OPS (eiOPS) samples. We also used eiOPS in the human macrophage THP-1 cell line and primary monocyte cultures to study inflammasome activation. FINDINGS: Different DAMPs were identified in eiOPS, several of which induced both priming and activation of the NLRP3 inflammasome in human myeloid cells. Cold ischemia time and donation after circulatory death negatively influenced the DAMP signature. Moreover, the presence of oligomeric inflammasomes and interleukin-18 in eiOPS correlated with early allograft dysfunction in liver transplant patients. INTERPRETATION: DAMPs released during cold ischemia storage prime and activate the NLRP3 inflammasome in liver macrophages after transplantation, inducing a pro-inflammatory environment that will complicate the outcome of the graft. The use of pharmacological blockers targeting DAMPs or the NLRP3 inflammasome in liver ischemia during static cold storage or through extracorporeal organ support could be a suitable strategy to increase the success of liver transplantation. FUNDING: Fundación Mutua Madrileña and Instituto de Salud Carlos III, Madrid, Spain.


Assuntos
Inflamassomos , Transplante de Fígado , Humanos , Aloenxertos , Isquemia Fria/efeitos adversos , Inflamassomos/metabolismo , Isquemia , Transplante de Fígado/efeitos adversos , Macrófagos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
18.
J Pathol Clin Res ; 9(2): 137-148, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36484086

RESUMO

The standardized preanalytical code (SPREC) aggregates warm ischemia (WIT), cold ischemia (CIT), and fixation times (FIT) in a precise format. Despite its growing importance underpinned by the European in vitro diagnostics regulation or broad preanalytical programs by the National Institutes of Health, little is known about its empirical occurrence in biobanked surgical specimen. In several steps, the Tissue Bank Bern achieved a fully informative SPREC code with insights from 10,555 CIT, 4,740 WIT, and 3,121 FIT values. During process optimization according to LEAN six sigma principles, we identified a dual role of the SPREC code as a sample characteristic and a traceable process parameter. With this preanalytical study, we outlined real-life data in a variety of organs with specific differences in WIT, CIT, and FIT values. Furthermore, our FIT data indicate the potential to adapt the SPREC fixation toward concrete paraffin-embedding time points and to extend its categories beyond 72 h due to weekend delays. Additionally, we identified dependencies of preanalytical variables from workload, daytime, and clinics that were actionable with LEAN process management. Thus, streamlined biobanking workflows during the day were significantly resilient to workload peaks, diminishing the turnaround times of native tissue processing (i.e. CIT) from 74.6 to 46.1 min under heavily stressed conditions. In conclusion, there are surgery-specific preanalytics that are surgico-pathologically limited even under process optimization, which might affect biomarker transfer from one entity to another. Beyond sample characteristics, SPREC coding is highly beneficial for tissue banks and Institutes of Pathology to track WIT, CIT, and FIT for process optimization and monitoring measurements.


Assuntos
Bancos de Espécimes Biológicos , Isquemia Fria , Estados Unidos , Humanos
19.
Rev. Cient. Esc. Estadual Saúde Pública de Goiás Cândido Santiago ; 9 (Ed. Especial, 1ª Oficina de Elaboração de Pareceres Técnicos Científicos (PTC): 9e9- EE3, 2023. ilus
Artigo em Português | LILACS, CONASS, Coleciona SUS, SES-GO | ID: biblio-1524143

RESUMO

Tecnologia: máquina de perfusão hipotérmica. Indicação: Transplante renal de doador falecido. Pergunta: Qual a efetividade da máquina de perfusão hipotérmica (HMP) para a preservação do rim de doador falecido, quando comparada ao armazenamento estático a frio (SCS)? Objetivo. Avaliar a efetividade da máquina de perfusão hipotérmica na preservação do rim de doador falecido, em comparação com o armazenamento estático a frio. Métodos: Revisão de revisões sistemáticas (overview) do tipo revisão rápida. Foi realizado um levantamento bibliográfico nas bases de dados: PubMed, Embase, BVS, Epistemonikos, Cochrane Library e em bases de registro de protocolos de revisões sistemáticas e ensaios clínicos, utilizando descritores e estratégias de busca predefinidas. A avaliação da qualidade metodológica dos estudos incluídos foi feita através da ferramenta AMSTAR-2 (Assessing the Methodological Quality of Systematic Reviews Version 2). Resultados: Duas revisões sistemáticas atenderam aos critérios de elegibilidade e foram incluídas na análise. Uma delas apresentou alto nível de qualidade metodológica. Conclusão: O uso da HMP para a preservação de rins de doadores falecidos foi associado a melhores desfechos clínicos relacionados à função retardada e à sobrevida do enxerto e foi considerado custo-efetivo, quando comparado ao SCS. Faz-se necessária a geração de evidências mais robustas acerca dos custos e benefícios do uso desta tecnologia no âmbito do SUS


Technology: hypothermic machine perfusion. Indication: Deceased donor kidney transplantation. Question: How effective is hypothermic machine perfusion (HMP) for preserving deceased donor kidneys compared to static cold storage (SCS)? Objective: To evaluate the effectiveness of the hypothermic machine perfusion in preserving the deceased donor kidney, compared to static cold storage. Methods: Rapid review of systematic reviews (overview). A bibliographic survey was carried out in the databases: PubMed, Embase, VHL, Epistemonikos, Cochrane Library and in databases of systematic review protocols and clinical trials, using predefined descriptors and search strategies. The assessment of the methodological quality of the included studies was performed using the AMSTAR-2 tool (Assessing the Methodological Quality of Systematic Reviews Version 2). Results: Two systematic reviews met the eligibility criteria and were included in the analysis. One of them performed a high level of methodological quality. Conclusion: The use of HMP for the preservation of deceased donor kidneys was associated with better clinical outcomes related to delayed graft function and graft survival and was considered cost-effective. It is necessary to generate more evidence about the costs and benefits of using this technology within the Brazilian Unified System of Healthcare (SUS)


Assuntos
Humanos , Masculino , Feminino , Preservação de Órgãos/métodos , Transplante de Rim , Isquemia Fria
20.
Exp Clin Transplant ; 20(11): 1035-1039, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36524890

RESUMO

In recent years, dual-kidney transplant has become an established method to overcome the inferior quality of donor organs and to allow the recovery of discarded human kidneys. However, in some cases, 1 of the 2 donor kidneys is unsuitable for transplant because of severe pathological changes, and the remaining marginal kidney is often discarded regardless of whether it meets criteria for dual-kidney transplant. Here, we report the use of marginal kidneys from 2 different donors, both of whom had missed kidney donation as a result of the serious pathological changes in their contralateral kidney. We combined the 2 donors' marginal kidneys for dual-kidney transplant, which were implanted into the right iliac fossa of the recipient after cold ischemia times of 13 hours 40 minutes and 30 hours 30 minutes, respectively. The recipient had fully recovered and showed favorable renal function without complications at discharge and at the 1.5-year follow-up. To the best of our knowledge, this is the first case report of successful unilateral dual-kidney transplant of discarded kidneys from 2 expanded criteria donors.


Assuntos
Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Resultado do Tratamento , Doadores de Tecidos , Rim/cirurgia , Rim/fisiologia , Rim/patologia , Isquemia Fria/efeitos adversos , Sobrevivência de Enxerto
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