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1.
Transpl Int ; 36: 11645, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37727383

RESUMO

Static Cold Storage (SCS) injures the bile duct, while the effect of Normothermic Machine Perfusion (NMP) is unknown. In a sub-study of the COPE trial on liver NMP, we investigated the impact of preservation type on histological bile duct injury score (BDIS). Transplants with at least one bile duct biopsy, either at end of preservation or 1 h post-reperfusion, were considered. BDIS was determined by assessing peribiliary glands injury, stromal and mural loss, haemorrhage, and thrombosis. A bivariate linear model compared BDIS (estimate, CI) between groups. Sixty-five transplants and 85 biopsies were analysed. Twenty-three grafts were preserved with SCS and 42 with NMP, with comparable baseline characteristics except for a shorter cold ischemic time in NMP. The BDIS increased over time regardless of preservation type (p = 0.04). The BDIS estimate was higher in NMP [8.02 (7.40-8.65)] than in SCS [5.39 (4.52-6.26), p < 0.0001] regardless of time. One patient in each group developed ischemic cholangiopathy, with a BDIS of 6 for the NMP-preserved liver. In six other NMP grafts, BDIS ranged 7-12 without development of ischemic cholangiopathy. In conclusion, BDIS increases over time, and the higher BDIS in NMP did not increase ischemic cholangiopathy. Thus, BDIS may overestimate this risk after liver NMP.


Assuntos
Ductos Biliares , Fígado , Humanos , Perfusão , Reperfusão , Biópsia
2.
Proc Natl Acad Sci U S A ; 117(46): 28960-28970, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33127761

RESUMO

Inhibition of the chemokine receptor CXCR4 in combination with blockade of the PD-1/PD-L1 T cell checkpoint induces T cell infiltration and anticancer responses in murine and human pancreatic cancer. Here we elucidate the mechanism by which CXCR4 inhibition affects the tumor immune microenvironment. In human immune cell-based chemotaxis assays, we find that CXCL12-stimulated CXCR4 inhibits the directed migration mediated by CXCR1, CXCR3, CXCR5, CXCR6, and CCR2, respectively, chemokine receptors expressed by all of the immune cell types that participate in an integrated immune response. Inhibiting CXCR4 in an experimental cancer medicine study by 1-wk continuous infusion of the small-molecule inhibitor AMD3100 (plerixafor) induces an integrated immune response that is detected by transcriptional analysis of paired biopsies of metastases from patients with microsatellite stable colorectal and pancreatic cancer. This integrated immune response occurs in three other examples of immune-mediated damage to noninfected tissues: Rejecting renal allografts, melanomas clinically responding to anti-PD1 antibody therapy, and microsatellite instable colorectal cancers. Thus, signaling by CXCR4 causes immune suppression in human pancreatic ductal adenocarcinoma and colorectal cancer by impairing the function of the chemokine receptors that mediate the intratumoral accumulation of immune cells.


Assuntos
Neoplasias Colorretais/metabolismo , Imunidade/imunologia , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Receptores CXCR4/efeitos dos fármacos , Receptores CXCR4/metabolismo , Idoso , Benzilaminas , Carcinoma Ductal Pancreático , Quimiocina CXCL12 , Neoplasias Colorretais/patologia , Ciclamos , Feminino , Compostos Heterocíclicos/antagonistas & inibidores , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Receptores CCR2/metabolismo , Receptores CXCR3/metabolismo , Receptores CXCR5/metabolismo , Receptores CXCR6/metabolismo , Receptores de Interleucina-8A/metabolismo , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/imunologia , Neoplasias Pancreáticas
3.
Anal Chem ; 94(3): 1795-1803, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35005896

RESUMO

Gemcitabine (dFdC) is a common treatment for pancreatic cancer; however, it is thought that treatment may fail because tumor stroma prevents drug distribution to tumor cells. Gemcitabine is a pro-drug with active metabolites generated intracellularly; therefore, visualizing the distribution of parent drug as well as its metabolites is important. A multimodal imaging approach was developed using spatially coregistered mass spectrometry imaging (MSI), imaging mass cytometry (IMC), multiplex immunofluorescence microscopy (mIF), and hematoxylin and eosin (H&E) staining to assess the local distribution and metabolism of gemcitabine in tumors from a genetically engineered mouse model of pancreatic cancer (KPC) allowing for comparisons between effects in the tumor tissue and its microenvironment. Mass spectrometry imaging (MSI) enabled the visualization of the distribution of gemcitabine (100 mg/kg), its phosphorylated metabolites dFdCMP, dFdCDP and dFdCTP, and the inactive metabolite dFdU. Distribution was compared to small-molecule ATR inhibitor AZD6738 (25 mg/kg), which was codosed. Gemcitabine metabolites showed heterogeneous distribution within the tumor, which was different from the parent compound. The highest abundance of dFdCMP, dFdCDP, and dFdCTP correlated with distribution of endogenous AMP, ADP, and ATP in viable tumor cell regions, showing that gemcitabine active metabolites are reaching the tumor cell compartment, while AZD6738 was located to nonviable tumor regions. The method revealed that the generation of active, phosphorylated dFdC metabolites as well as treatment-induced DNA damage primarily correlated with sites of high proliferation in KPC PDAC tumor tissue, rather than sites of high parent drug abundance.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Animais , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Camundongos , Imagem Multimodal , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Microambiente Tumoral , Gencitabina
4.
Liver Transpl ; 26(8): 1000-1009, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32108995

RESUMO

Cholangiocytes secrete bicarbonate and absorb glucose, producing bile with alkaline pH and low glucose content. These functions of cholangiocytes have been suggested as a marker of bile duct viability during normothermic ex situ liver perfusion, and they are now monitored routinely after reperfusion in our center. In this study, we reviewed the composition of bile immediately after reperfusion in liver transplant recipients to determine normal posttransplant parameters and the predictive value of bile biochemistry for the later development of cholangiopathy. After reperfusion of the liver graft, a cannula was placed in the bile duct to collect bile over a median 44-minute time period. The bile produced was analyzed using a point-of-care blood gas analyzer (Cobas b221, Roche Diagnostics, Indianapolis, IN). A total of 100 liver transplants (35 from donation after circulatory death and 65 from donation after brain death) were studied. Median bile pH was 7.82 (interquartile range [IQR], 7.67-7.98); median bile glucose was 2.1 (1.4-3.7) mmol/L; median blood-bile-blood pH difference was 0.50 (0.37-0.62); and median blood-bile glucose difference was 7.1 (5.6-9.1) mmol/L. There were 12 recipients who developed cholangiopathy over a median follow-up of 15 months (IQR, 11-20 months). Bile sodium (142 versus 147 mmol/L; P = 0.02) and blood-bile glucose concentration differences (5.2 versus 7.6 mmol/L; P = 0.001) were significantly lower and were associated with ischemic cholangiopathy. In conclusion, bile biochemistry may provide useful insights into cholangiocyte function and, hence, bile duct viability. Our results suggest bile glucose is the most sensitive predictor of cholangiopathy.


Assuntos
Bile , Transplante de Fígado , Ductos Biliares , Humanos , Fígado , Transplante de Fígado/efeitos adversos , Perfusão , Reperfusão
5.
BMC Cancer ; 20(1): 38, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941506

RESUMO

BACKGROUND: Pancreatic adenosquamous carcinoma has a poor prognosis, with limited prospective trial data to guide optimal treatment. The potential impact of drug metabolism on the treatment response of patients with pancreatic adenosquamous carcinoma is largely unknown. CASE PRESENTATION: We describe the case of a 51 year old woman with pancreatic adenosquamous carcinoma who, following surgical resection, experienced early disease relapse during adjuvant gemcitabine therapy. Paradoxically, this was followed by an exceptional response to capecitabine therapy lasting 34.6 months. Strong expression of cytidine deaminase was detected within the tumour. CONCLUSIONS: This case study demonstrates that early relapse during adjuvant chemotherapy for pancreatic adenosquamous carcinoma may be compatible with a subsequent exceptional response to second line chemotherapy, an important observation given the poor overall prognosis of patients with adenosquamous carcinoma. Cytidine deaminase is predicted to inactivate gemcitabine and, conversely, catalyze capecitabine activation. We discuss strong intra-tumoural expression of cytidine deaminase as a potential mechanism to explain this patient's disparate responses to gemcitabine and capecitabine therapy, and highlight the benefit that may be gained from considering similar determinants of response to chemotherapy in clinical practice.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Carcinoma Adenoescamoso/tratamento farmacológico , Carcinoma Adenoescamoso/genética , Citidina Desaminase/genética , Desoxicitidina/análogos & derivados , Expressão Gênica , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Carcinoma Adenoescamoso/diagnóstico , Quimioterapia Adjuvante , Citidina Desaminase/metabolismo , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Feminino , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/mortalidade , Recidiva , Retratamento , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Gencitabina
6.
Am J Transplant ; 18(8): 2005-2020, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29419931

RESUMO

Normothermic ex situ liver perfusion might allow viability assessment of livers before transplantation. Perfusion characteristics were studied in 47 liver perfusions, of which 22 resulted in transplants. Hepatocellular damage was reflected in the perfusate transaminase concentrations, which correlated with posttransplant peak transaminase levels. Lactate clearance occurred within 3 hours in 46 of 47 perfusions, and glucose rose initially during perfusion in 44. Three livers required higher levels of bicarbonate support to maintain physiological pH, including one developing primary nonfunction. Bile production did not correlate with viability or cholangiopathy, but bile pH, measured in 16 of the 22 transplanted livers, identified three livers that developed cholangiopathy (peak pH < 7.4) from those that did not (pH > 7.5). In the 11 research livers where it could be studied, bile pH > 7.5 discriminated between the 6 livers exhibiting >50% circumferential stromal necrosis of septal bile ducts and 4 without necrosis; one liver with 25-50% necrosis had a maximum pH 7.46. Liver viability during normothermic perfusion can be assessed using a combination of transaminase release, glucose metabolism, lactate clearance, and maintenance of acid-base balance. Evaluation of bile pH may offer a valuable insight into bile duct integrity and risk of posttransplant ischemic cholangiopathy.


Assuntos
Ductos Biliares/metabolismo , Hepatócitos/metabolismo , Transplante de Fígado , Preservação de Órgãos/métodos , Perfusão/métodos , Disfunção Primária do Enxerto/prevenção & controle , Doadores de Tecidos/provisão & distribuição , Adulto , Biomarcadores/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Traumatismo por Reperfusão/prevenção & controle , Obtenção de Tecidos e Órgãos/normas , Adulto Jovem
7.
Liver Transpl ; 24(2): 171-181, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29156507

RESUMO

Common variable immunodeficiency (CVID) is the most common form of primary immunodeficiency characterized by antibody deficiency, recurrent bacterial infections, and autoimmunity. Advanced chronic liver disease occurs in a subset of patients with CVID and manifests with various histological features, such as nodular regenerative hyperplasia, inflammation, fibrosis, and cholangiopathy. We present a case series characterizing the outcomes in adult patients transplanted for primary CVID-related liver disease. We discuss the unique transplantation challenges faced in this primary immunodeficiency group including susceptibility to infections and early disease recurrence. There is a statistically significant decrease in 3-year and 5-year survival after liver transplantation in those with CVID-related liver disease (55% at 3 and 5 years) compared with all-comers (89% at 3 years, 81% at 5 years), prompting a need for discussion of suitability of transplantation in this group of patients as well as methods for reducing posttransplantation risk such as scrupulous search for infectious agents and reduction of immunosuppression. Liver Transplantation 24 171-181 2018 AASLD.


Assuntos
Imunodeficiência de Variável Comum/imunologia , Hepatopatias/cirurgia , Transplante de Fígado/efeitos adversos , Adulto , Doença Crônica , Imunodeficiência de Variável Comum/complicações , Imunodeficiência de Variável Comum/diagnóstico , Evolução Fatal , Feminino , Humanos , Hospedeiro Imunocomprometido , Imunossupressores/efeitos adversos , Hepatopatias/diagnóstico , Hepatopatias/imunologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
8.
Histopathology ; 69(2): 315-21, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26826338

RESUMO

AIMS: Liver pathology is a challenging subspeciality, with histopathologists frequently seeking specialist opinions. This study aims to determine the impact of specialist reviews on the final diagnosis and patient management. METHODS AND RESULTS: Agreement with the initial reporting centre in the histopathological diagnosis of 1265 liver biopsies was determined. The nature of differences was explored in more depth for 103 discrepant cases. Differences in the histopathological interpretation were present in 749 of 1265 (59%) biopsies, of which 505 of 749 (67%) were predicted at the time of reporting to impact upon patient management. Agreement was good in cases with chronic viral hepatitis, fatty liver disease, malignancy and minimal pathological changes, while diagnostic differences occurred in more than 70% with biliary disease, autoimmune hepatitis or vascular/architectural changes. A clinical review of a subset of reports with histopathological differences predicted changes in patient management in 63 of 103 (61%). CONCLUSIONS: Clinically significant differences in liver biopsy interpretation between local pathologists and subspecialists are common. Diagnoses with frequent discrepancies, such as biliary disease, may benefit from a specialist review as standard when diagnosed initially, while cases requiring specialist advice from disease subgroups where discrepancies are less common, such as chronic viral hepatitis, could be selected during the clinicopathological conference process.


Assuntos
Fígado Gorduroso/diagnóstico , Hepatite Autoimune/diagnóstico , Hepatopatias/diagnóstico , Fígado/patologia , Encaminhamento e Consulta/normas , Biópsia , Erros de Diagnóstico/prevenção & controle , Fígado Gorduroso/patologia , Hepatite Autoimune/patologia , Humanos , Hepatopatias/patologia , Especialização
9.
Liver Transpl ; 21(4): 487-99, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25545865

RESUMO

Ischemia/reperfusion injury (IRI) that develops after liver implantation may prejudice long-term graft survival, but it remains poorly understood. Here we correlate the severity of IRIs that were determined by histological grading of time-zero biopsies sampled after graft revascularization with patient and graft outcomes. Time-zero biopsies of 476 liver transplants performed at our center between 2000 and 2010 were graded as follows: nil (10.5%), mild (58.8%), moderate (26.1%), and severe (4.6%). Severe IRI was associated with donor age, donation after circulatory death, prolonged cold ischemia time, and liver steatosis, but it was also associated with increased rates of primary nonfunction (9.1%) and retransplantation within 90 days (22.7%). Longer term outcomes in the severe IRI group were also poor, with 1-year graft and patient survival rates of only 55% and 68%, respectively (cf. 90% and 93% for the remainder). Severe IRI on the time-zero biopsy was, in a multivariate analysis, an independent determinant of 1-year graft survival and was a better predictor of 1-year graft loss than liver steatosis, early graft dysfunction syndrome, and high first-week alanine aminotransferase with a positive predictive value of 45%. Time-zero biopsies predict adverse clinical outcomes after liver transplantation, and severe IRI upon biopsy signals the likely need for early retransplantation.


Assuntos
Transplante de Fígado/efeitos adversos , Traumatismo por Reperfusão/patologia , Adulto , Fatores Etários , Idoso , Alanina Transaminase/sangue , Aloenxertos , Biomarcadores/sangue , Biópsia , Isquemia Fria/efeitos adversos , Feminino , Sobrevivência de Enxerto , Humanos , Estimativa de Kaplan-Meier , Transplante de Fígado/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/mortalidade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Doadores de Tecidos , Resultado do Tratamento , Adulto Jovem
10.
Pancreatology ; 15(2): 179-84, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25579809

RESUMO

BACKGROUND: Post-operative pancreatic fistula (POPF) is the major source of morbidity following pancreaticoduodenectomy. A predictive indicator would be highly advantageous. One potential marker is drain amylase concentration (DAC). However, its predictive value has not been fully established. METHODS: 405 patients undergoing pancreaticoduodenectomy at our centre over a 10 year period were reviewed to determine the value of DAC as a predictive indicator for the development of POPF. RESULTS: POPF developed in 58 patients (14%). These patients suffered greater morbidity. Overall 30-day mortality was 1.5%. Male gender (OR: 5.1; p = 0.0082) and age > 70 (OR 2; p = 0.0372) were independent risk factors for POPF, whilst Type 2 diabetes (OR: 0.2321; p = 0.0090) and pancreatic ductal-adenocarcinoma (OR: 0.3721; p = 0.0039) decreased POPF risk. The DACs post-operatively were significantly higher in those developing POPF, but with significant overlap. ROC curves revealed optimal threshold values for differentiating POPF and non-POPF patients. A DAC°<°1400 U/ml on day 1 and <768 U/ml on day 2, although having a poor positive predictive value (32-44%), had a very strong negative predictive value (97-99%). CONCLUSION: Our data suggest that post-operative DAC below the determined optimal threshold values on day 1 and 2 following pancreaticoduodenectomy carries high negative predictive value for POPF development and identifies patients in whom early drain removal, and enhanced recovery may be considered, with simultaneous assessment of operative and clinical factors.


Assuntos
Amilases/análise , Fístula Pancreática/enzimologia , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/complicações , Carcinoma Ductal Pancreático/cirurgia , Drenagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Pancreática/epidemiologia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/cirurgia , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/epidemiologia , Valor Preditivo dos Testes , Fatores de Risco , Fatores Sexuais , Resultado do Tratamento , Adulto Jovem
11.
Transplantation ; 108(6): 1383-1393, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38409681

RESUMO

BACKGROUND: Bile chemistry during normothermic ex situ liver perfusion (NESLiP) has been suggested to be an indicator of cholangiopathy. The normal range of biochemical variables in bile of livers undergoing NESLiP has not been defined, nor have published biliary viability criteria been assessed against instances of posttransplant nonanastomotic bile strictures (NASs). METHODS: The bile and perfusate chemistry of 200 livers undergoing NESLiP between February 1, 2018, and October 30, 2023, was compared. In addition, 11 livers that underwent NESLiP and later developed NAS were selected and their bile chemistry was also examined. RESULTS: In livers that did not develop cholangiopathy, concentrations of sodium, potassium, and chloride were slightly higher in bile than in perfusate, whereas the concentration of calcium was slightly lower. Bile was alkali and had a lower glucose concentration than perfusate. Cholangiocyte glucose reabsorption was shown to saturate at high perfusate concentrations and was more impaired in livers donated after circulatory death than in livers donated after brain death. Published criteria failed to identify all livers that went on to develop NASs. CONCLUSIONS: A significant false-negative rate exists with current biliary viability criteria, probably reflecting the patchy and incomplete nature of the development of NASs in the biliary tree. The data presented here provide a benchmark for future assessment of bile duct chemistry during NESLiP.


Assuntos
Bile , Transplante de Fígado , Fígado , Preservação de Órgãos , Perfusão , Humanos , Transplante de Fígado/efeitos adversos , Bile/metabolismo , Bile/química , Preservação de Órgãos/métodos , Fígado/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Colestase , Adulto , Estudos Retrospectivos , Constrição Patológica
12.
Australas J Dermatol ; 54(2): 133-5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23581997

RESUMO

Calciphylaxis is a rare life-threatening form of skin necrosis. Although traditionally observed in patients with end-stage renal disease and/or hyperparathyroidism, calciphylaxis has also been reported to occur in 'non-traditional' patients with normal renal and parathyroid function. We report a case of warfarin-induced calciphylaxis treated successfully with sodium thiosulphate and discuss the role of Vitamin K2 as a potential therapeutic option in the management of warfarin-induced calciphylaxis.


Assuntos
Anticoagulantes/efeitos adversos , Antioxidantes/uso terapêutico , Calciofilaxia/induzido quimicamente , Calciofilaxia/tratamento farmacológico , Tiossulfatos/uso terapêutico , Varfarina/efeitos adversos , Toxidermias/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Cutânea/induzido quimicamente , Úlcera Cutânea/terapia
13.
Transplantation ; 107(6): 1311-1321, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36728501

RESUMO

BACKGROUND: Deceased donor livers are prone to biliary complications, which may necessitate retransplantation, and we, and others, have suggested that these complications are because of peribiliary vascular fibrin microthrombi. We sought to determine the prevalence and consequence of occult fibrin within deceased donor livers undergoing normothermic ex situ perfusion (NESLiP) and evaluate a role for fibrinolysis. METHODS: D-dimer concentrations, products of fibrin degradation, were assayed in the perfusate of 163 livers taken after 2 h of NESLiP, including 91 that were transplanted. These were related to posttransplant outcomes. Five different fibrinolytic protocols during NESLiP using alteplase were evaluated, and the transplant outcomes of these alteplase-treated livers were reviewed. RESULTS: Perfusate D-dimer concentrations were lowest in livers recovered using in situ normothermic regional perfusion and highest in alteplase-treated livers. D-dimer release from donation after brain death livers was significantly correlated with the duration of cold ischemia. In non-alteplase-treated livers, Cox proportional hazards regression analysis showed that D-dimer levels were associated with transplant survival ( P = 0.005). Treatment with alteplase and fresh frozen plasma during NESLiP was associated with significantly more D-dimer release into the perfusate and was not associated with excess bleeding postimplantation; 8 of the 9 treated livers were free of cholangiopathy, whereas the ninth had a proximal duct stricture. CONCLUSIONS: Fibrin is present in many livers during cold storage and is associated with poor posttransplant outcomes. The amount of D-dimer released after fibrinolytic treatment indicates a significant occult fibrin burden and suggests that fibrinolytic therapy during NESLiP may be a promising therapeutic intervention.


Assuntos
Transplante de Fígado , Humanos , Transplante de Fígado/efeitos adversos , Fibrina/metabolismo , Preservação de Órgãos/métodos , Fígado/irrigação sanguínea , Perfusão/métodos
14.
J Immunother Cancer ; 11(8)2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553182

RESUMO

BACKGROUND: The prognosis for patients with pancreatic ductal adenocarcinoma (PDAC) remains extremely poor. It has been suggested that the adenosine pathway contributes to the ability of PDAC to evade the immune system and hence, its resistance to immuno-oncology therapies (IOT), by generating extracellular adenosine (eAdo). METHODS: Using genetically engineered allograft models of PDAC in syngeneic mice with defined and different immune infiltration and response to IOT and autochthonous tumors in KPC mice we investigated the impact of the adenosine pathway on the PDAC tumor microenvironment (TME). Flow cytometry and imaging mass cytometry (IMC) were used to characterize the subpopulation frequency and spatial distribution of tumor-infiltrating immune cells. Mass spectrometry imaging (MSI) was used to visualize adenosine compartmentalization in the PDAC tumors. RNA sequencing was used to evaluate the influence of the adenosine pathway on the shaping of the immune milieu and correlate our findings to published data sets in human PDAC. RESULTS: We demonstrated high expression of adenosine pathway components in tumor-infiltrating immune cells (particularly myeloid populations) in the murine models. MSI demonstrated that extracellular adenosine distribution is heterogeneous in tumors, with high concentrations in peri-necrotic, hypoxic regions, associated with rich myeloid infiltration, demonstrated using IMC. Protumorigenic M2 macrophages express high levels of the Adora2a receptor; particularly in the IOT resistant model. Blocking the in vivo formation and function of eAdo (Adoi), using a combination of anti-CD73 antibody and an Adora2a inhibitor slowed tumor growth and reduced metastatic burden. Additionally, blocking the adenosine pathway improved the efficacy of combinations of cytotoxic agents or immunotherapy. Adoi remodeled the TME, by reducing the infiltration of M2 macrophages and regulatory T cells. RNA sequencing analysis showed that genes related to immune modulation, hypoxia and tumor stroma were downregulated following Adoi and a specific adenosine signature derived from this is associated with a poorer prognosis in patients with PDAC. CONCLUSIONS: The formation of eAdo promotes the development of the immunosuppressive TME in PDAC, contributing to its resistance to conventional and novel therapies. Therefore, inhibition of the adenosine pathway may represent a strategy to modulate the PDAC immune milieu and improve therapy response in patients with PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Adenosina , Carcinoma Ductal Pancreático/patologia , Neoplasias Pancreáticas/patologia , Imunoterapia/métodos , Microambiente Tumoral
15.
Pancreatology ; 12(1): 8-15, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22487467

RESUMO

OBJECTIVE: Current practice to diagnose pancreatic cancer is accomplished by endoscopic ultrasound guided fine needle aspiration (EUS-FNA) using a cytological approach. This method is time consuming and often fails to provide suitable specimens for modern molecular analyses. Here, we compare the cytological approach with direct formalin fixation of pancreatic EUS-FNA micro-cores and evaluate the potential to perform molecular biomarker analysis on these specimen. METHODS: 130 specimens obtained by EUS-FNA with a 22G needle were processed by the standard cytological approach and compared to a separate cohort of 130 specimens that were immediately formalin fixed to preserve micro-cores of tissue prior to routine histological processing. RESULTS: We found that direct formalin fixation significantly shortened the time required for diagnosis from 3.6 days to 2.9 days (p<0.05) by reducing the average time (140 vs 33 min/case) and number of slides (9.65 vs 4.67 slides/case) for histopathological processing. Specificity and sensitivity yielded comparable results between the two approaches (82.3% vs 77% and 90.9% vs 100%). Importantly, EUS-FNA histology preserved the tumour tissue architecture with neoplastic glands embedded in stroma in 67.89% of diagnostic cases compared to 27.55% with the standard cytological approach (p < 0.001). Furthermore, micro-core samples were suitable for molecular studies including the immunohistochemical detection of intranuclear Hes1 in malignant cells, and the laser-capture microdissection-mediated measurement of Gli-1 mRNA in tumour stromal myofibroblasts. CONCLUSIONS: Direct formalin fixation of pancreatic EUS-FNA micro-cores demonstrates superiority regarding diagnostic delay, costs, and specimen suitability for molecular studies. We advocate this approach for future investigational trials in pancreatic cancer patients.


Assuntos
Biomarcadores Tumorais/análise , Biópsia por Agulha Fina/métodos , Endossonografia/métodos , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/análise , Feminino , Fixadores , Formaldeído , Proteínas de Homeodomínio/análise , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Fatores de Tempo , Fatores de Transcrição HES-1 , Ultrassonografia de Intervenção
16.
Transplantation ; 106(12): 2391-2398, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36044364

RESUMO

BACKGROUND: Normothermic ex situ liver perfusion is increasingly used to assess donor livers, but there remains a paucity of evidence regarding criteria upon which to base a viability assessment or criteria predicting early allograft function. METHODS: Perfusate variables from livers undergoing normothermic ex situ liver perfusion were analyzed to see which best predicted the Model for Early Allograft Function score. RESULTS: One hundred fifty-four of 203 perfused livers were transplanted following our previously defined criteria. These comprised 84/123 donation after circulatory death livers and 70/80 donation after brain death livers. Multivariable analysis suggested that 2-h alanine transaminase, 2-h lactate, 11 to 29 mmol supplementary bicarbonate in the first 4 h, and peak bile pH were associated with early allograft function as defined by the Model for Early Allograft Function score. Nonanastomotic biliary strictures occurred in 11% of transplants, predominantly affected first- and second-order ducts, despite selection based on bile glucose and pH. CONCLUSIONS: This work confirms the importance of perfusate alanine transaminase and lactate at 2-h, as well as the amount of supplementary bicarbonate required to keep the perfusate pH > 7.2, in the assessment of livers undergoing perfusion. It cautions against the use of lactate as a sole indicator of viability and also suggests a role for cholangiocyte function markers in predicting early allograft function.


Assuntos
Bicarbonatos , Transplante de Fígado , Alanina Transaminase , Transplante de Fígado/efeitos adversos , Perfusão/efeitos adversos , Fígado , Lactatos , Aloenxertos , Preservação de Órgãos
17.
Endosc Int Open ; 8(11): E1537-E1544, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33140008

RESUMO

Background and study aims Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) has emerged as an important method for obtaining a preoperative tissue diagnosis for suspected cholangiocarcinoma. However, doubts remain about test sensitivity. This study assessed the value and limitations of EUS-FNA in clinical practice. Patients and methods Patients undergoing EUS-FNA for biliary strictures/masses at a UK tertiary referral center from 2005 to 2014 were prospectively enrolled. Data on EUS-FNA findings, histology, and endoscopy and patient outcomes were collected to evaluate test performance and identify factors predictive of an inaccurate diagnostic result. Results Ninety-seven patients underwent a total of 112 EUS-FNA procedures. Overall test sensitivity for an initial EUS-FNA for suspected cholangiocarcinoma was 75 % (95 % CI 64 %-84 %), with specificity 100 % (95 % CI 85 %-100 %) and negative predictive value 0.62 (95 % CI 0.47-0.75). Hilar lesions, the presence of a biliary stent, and a diagnosis of PSC were significantly independently associated with an inaccurate result. For the most difficult cases, repeat sampling and use of the Papanicolaou cytopathology grading scale led to an increase in test sensitivity from 17 % to 100 % ( P  = 0.015) with no loss of specificity. Conclusions EUS-FNA was found to be a useful method for obtaining a preoperative tissue diagnosis for patients with suspected cholangiocarcinoma. This study identified markers that can reduce test accuracy and measures that can improve test performance of EUS-FNA.

18.
Nat Commun ; 11(1): 307, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949142

RESUMO

Autophagy is an important cellular degradation pathway with a central role in metabolism as well as basic quality control, two processes inextricably linked to ageing. A decrease in autophagy is associated with increasing age, yet it is unknown if this is causal in the ageing process, and whether autophagy restoration can counteract these ageing effects. Here we demonstrate that systemic autophagy inhibition induces the premature acquisition of age-associated phenotypes and pathologies in mammals. Remarkably, autophagy restoration provides a near complete recovery of morbidity and a significant extension of lifespan; however, at the molecular level this rescue appears incomplete. Importantly autophagy-restored mice still succumb earlier due to an increase in spontaneous tumour formation. Thus, our data suggest that chronic autophagy inhibition confers an irreversible increase in cancer risk and uncovers a biphasic role of autophagy in cancer development being both tumour suppressive and oncogenic, sequentially.


Assuntos
Envelhecimento/fisiologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Longevidade/fisiologia , Neoplasias , Envelhecimento/genética , Animais , Autofagia/genética , Proteína 5 Relacionada à Autofagia/genética , Transplante de Medula Óssea , Modelos Animais de Doenças , Feminino , Inflamação , Longevidade/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculos , Fenótipo , Proteína Sequestossoma-1/metabolismo , Pele/patologia
19.
Br J Radiol ; 92(1103): 20190461, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31430199

RESUMO

OBJECTIVE: Main duct and mixed intraductal papillary mucinous neoplasms (IPMN) are pre-malignant cystic pancreatic neoplasms associated with pancreatic duct dilatation. Distinguishing these from benign causes of pancreatic duct dilatation is important in order to allow appropriate surveillance or surgery. A patulous duodenal papilla with extrusion of mucus at endoscopic evaluation, the endoscopic fish mouth ampulla (E-FMA) sign, is reported in main duct and mixed IPMN. We aimed to establish whether a CT correlate (CT-FMA) of this sign exists and whether this was associated with the presence of invasion or high-grade dysplasia. We defined the CT-FMA sign as an uninterrupted column of water attenuation material running from the pancreatic duct to the duodenal lumen. METHODS: A retrospective, blinded review of 44 patients with histologically confirmed IPMN and 87 age-matched controls with pancreatic duct dilatation on CT was undertaken. A case-control series matched for the degree of pancreatic duct dilatation was used to compare the rates of invasion or high-grade dysplasia between main duct and mixed IPMN patients, with and without a CT-FMA sign. RESULTS: The CT-FMA sign could be identified in 18.5% patients with main duct/mixed IPMN with specificity 100%, positive predictive value 100% and negative predictive value 79.8%. A significant association was found between CT-FMA in main duct/mixed IPMN compared to controls, but not with the presence of high-grade dysplasia or invasion. CONCLUSIONS: The CT-FMA sign is a newly reported, highly specific sign of MD and mixed IPMN. ADVANCES IN KNOWLEDGE: If a fish mouth ampulla is identified at CT, a diagnosis of main duct or mixed IPMN is highly likely.


Assuntos
Adenocarcinoma Mucinoso/diagnóstico por imagem , Carcinoma Ductal Pancreático/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Ampola Hepatopancreática/diagnóstico por imagem , Estudos de Casos e Controles , Humanos , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
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