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1.
Cureus ; 16(1): e51930, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38333480

RESUMO

Megaduodenum is a rare clinical syndrome characterized by significant duodenal dilation, elongation, and hypertrophy. Given its rarity and nonspecific clinical manifestations, megaduodenum may be misdiagnosed, leading to delays in surgical care and increased morbidity. We describe a case of idiopathic megaduodenum in a teenage Caucasian female, who presented with a five-year history of halitosis, recurrent belching, bloating, nausea and vomiting, and postprandial epigastric abdominal pain. She was diagnosed with megaduodenum by dramatic findings on contrast radiography. She developed a duodenal volvulus necessitating emergency exploratory laparotomy, during which a duodenal plication and a side-to-side duodenojejunostomy were performed. Exploratory laparotomy and histopathological analysis were unrevealing of any definitive abnormalities to explain her megaduodenum. Postoperatively, she developed two early small bowel obstructions, both from subsequent adhesions requiring repeat laparotomy with adhesiolysis. She has subsequently recovered without incident. Diagnosis and accurate classification of megaduodenum requires surgical exploration with a full-thickness biopsy and subsequent histopathologic analysis to rule out obstructive or functional disorders of the duodenum. Treatment of megaduodenum depends on the underlying cause and degree of duodenal distention. It is crucial that clinicians are knowledgeable of the various surgical options, their indications, and the potential postoperative complications that may arise.

3.
J Immunol Methods ; 511: 113363, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36174734

RESUMO

BACKGROUND: Given the role of B cells in sensitization and antibody-mediated rejection pathogenesis, the ability to identify, isolate, and study B cells in vitro is critical for understanding these processes and developing novel therapeutics. While in vivo nonhuman primate models have been used to this end, an in vitro nonhuman primate model of B cell activation and proliferation has not been developed. METHODS: CD20+ B cells and CD3+ T cells were isolated using magnetic bead separation from the peripheral blood of naive and skin allograft sensitized nonhuman primates. Allogeneic B and T cells were co-cultured in plates pre-coated with murine stromal cells engineered to express human CD40L and stimulated with cytokines. Cells and supernatants were harvested every 2 days for immune phenotyping and donor specific antibody quantification by flow cytometry. RESULTS: The optimized culture system consisted of MS40L cells co-cultured with B and allogenic T cells and stimulated with cytokines. This culture system resulted in increased memory cells and plasmablasts over time compared to other culture systems. Comparison of culture of naïve and sensitized nonhuman primate samples revealed faster B cell exhaustion and marginally increased plasmablast differentiation in sensitized culture. Donor-specific antibody production was not observed in either culture group. CONCLUSIONS: This study describes the first in vitro nonhuman primate model of B cell activation and proliferation using both naïve and allosensitized samples. This model provides an opportunity for exploration of B cell mechanisms and novel therapeutics and is a preliminary step in the development of an in vitro germinal center model.


Assuntos
Humanos , Animais , Camundongos
4.
HPB (Oxford) ; 24(7): 1153-1161, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34987008

RESUMO

BACKGROUND: Standard of care for resectable pancreatic cancer is a combination of surgical resection (SR) and multiagent chemotherapy (MCT). We aim to determine whether SR or MCT is associated with superior survival for patients receiving only single-modality therapy. METHODS: Patients with stage I-IIb pancreatic head adenocarcinoma who received either MCT or SR were identified in the NCDB (2013-2015). Following a piecewise approach to estimating hazards over the course of follow-up, conditional overall survival (OS) at 30, 60, and 90 days after treatment initiation was estimated using landmark analyses. RESULTS: 3103 patients received MCT alone (60.3%) and 2043 underwent SR alone (39.7%). SR had an OS disadvantage at 30 (HR 3.99, 95% CI 3.12-5.11) and 60 days (HR 1.85, 95% CI 1.4-2.45), but an OS advantage after 90 days (HR 0.59, 95% CI 0.55-0.64). In a landmark analysis conditioned on 90 days survival post treatment initiation, median OS was improved for SR (17.0 vs. 12.2 months, p < 0.0001); SR improved 3-year OS by 21.3% (p < 0.05), despite patients being older (median 72 vs. 67 years, p < 0.0001) with higher Charlson-Deyo comorbidity scores (≥2: 11.2 vs. 8.6%, p = 0.006). CONCLUSION: For patients with resectable pancreatic cancer, SR is associated with superior long-term survival compared to MCT.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/cirurgia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas
5.
Anticancer Res ; 42(2): 629-639, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35093860

RESUMO

Pancreatic neuroendocrine tumors (PNETs) arise from endocrine pancreatic cells and comprise 3-5% of pancreatic cancers. Surgical resection is the only potentially curative option for PNETs. Surgical candidates should be carefully selected according to tumor functionality, size, location, grade, and stage. Current guidelines state that patients with neuroendocrine carcinoma may not be surgical candidates due to aggressive tumor behavior and poor prognosis, while in cases of PNET with unresectable metastatic disease, resection may be of benefit in certain patients. The current guidelines recommend resection of any size of functional PNETs and of non-functional PNETs >2 cm. Watchful waiting is recommended for patients with non-functional PNETs <1 cm. Further evidence is needed to determine whether surgery for non-functional PNETs of 1-2 cm would be of benefit or if surgery should be individualized. This review aimed to discuss the current literature on the management of PNETs and highlight the utility of surgery in treatment.


Assuntos
Tumores Neuroendócrinos/cirurgia , Neoplasias Pancreáticas/cirurgia , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos , Gradação de Tumores , Estadiamento de Neoplasias , Tumores Neuroendócrinos/diagnóstico , Tumores Neuroendócrinos/patologia , Pancreatectomia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Seleção de Pacientes , Resultado do Tratamento
6.
Kidney360 ; 3(12): 2116-2130, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36591367

RESUMO

Preexisting donor-specific antibodies (DSA) to MHC antigens increase the risk of antibody-mediated rejection (AMR) in sensitized transplant recipients and reduces graft survival. Pretransplant desensitization with costimulation blockade and proteasome inhibition has facilitated transplantation in our preclinical nonhuman primate (NHP) model. However, long-term graft survival is limited by rebound of DSA after transplantation. In this study, we performed kidney transplants between highly sensitized, maximally MHC-mismatched NHPs (n=14). At kidney transplantation, primates received T cell depletion with rhesus-specific anti-thymocyte globulin (rhATG; n=10) or monoclonal anti-CD4 and anti-CD8 antibodies (n=4). Maintenance immunosuppression consisted of belatacept and tacrolimus (n=5) or belatacept and rapamycin (n=9) with steroids. Rebound of DSA post-kidney transplantation was significantly reduced compared with maintenance immunosuppression with tacrolimus, mycophenolate, and steroids. Protocol lymph node biopsy specimens showed a decrease in germinal center activity, with low frequencies of T follicular helper cells and class-switched B cells after kidney transplantation. Combined belatacept and rapamycin was superior in controlling viral reactivation, enabling weaning of ganciclovir prophylaxis. Tacrolimus was associated with increased morbidity that included cytomegalovirus and parvovirus viremia and post-transplant lymphoproliferative disorder. All primates in the tacrolimus/belatacept group failed discontinuation of antiviral therapy. Overall, belatacept-based immunosuppression increased AMR-free graft survival by controlling post-transplant humoral responses in highly sensitized NHP recipients and should be further investigated in a human clinical trial.


Assuntos
Imunidade Humoral , Tacrolimo , Animais , Abatacepte/farmacologia , Abatacepte/uso terapêutico , Anticorpos , Terapia de Imunossupressão , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Tacrolimo/farmacologia , Tacrolimo/uso terapêutico
7.
Xenotransplantation ; 28(6): e12713, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34951057

RESUMO

Porcine islet xenotransplantation is a viable strategy to treat diabetes. Its translation has been limited by the pre-clinical development of a clinically available immunosuppressive regimen. We tested two clinically relevant induction agents in a non-human primate (NHP) islet xenotransplantation model to compare depletional versus nondepletional induction immunosuppression. Neonatal porcine islets were isolated from GKO or hCD46/GKO transgenic piglets and transplanted via portal vein infusion in diabetic rhesus macaques. Induction therapy consisted of either basiliximab (n = 6) or rhesus-specific anti-thymocyte globulin (rhATG, n = 6), combined with a maintenance regimen using B7 costimulation blockade, tacrolimus with a delayed transition to sirolimus, and mycophenolate mofetil. Xenografts were monitored by blood glucose levels and porcine C-peptide measurements. Of the six receiving basiliximab induction, engraftment was achieved in 4 with median graft survival of 14 days. All six receiving rhATG induction engrafted with significantly longer xenograft survival at 40.5 days (P = 0.03). These data suggest that depletional induction provides superior xenograft survival to nondepletional induction, in the setting of a costimulation blockade-based maintenance regimen.


Assuntos
Soro Antilinfocitário , Transplante das Ilhotas Pancreáticas , Animais , Soro Antilinfocitário/farmacologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Humanos , Imunossupressores/farmacologia , Macaca mulatta , Suínos , Transplante Heterólogo
8.
J Biomed Opt ; 26(9)2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34561973

RESUMO

SIGNIFICANCE: The current gold standard for monitoring small intestinal transplant (IT) rejection is endoscopic visual assessment and biopsy of suspicious lesions; however, these lesions are only superficially visualized by endoscopy. Invasive biopsies provide a coarse sampling of tissue health without depicting the true presence and extent of any pathology. Optical coherence tomography (OCT) presents a potential alternative approach with significant advantages over traditional white-light endoscopy. AIM: The aim of our investigation was to evaluate OCT performance in distinguishing clinically relevant morphological features associated with IT graft failure. APPROACH: OCT was applied to evaluate the small bowel tissues of two rhesus macaques that had undergone IT of the ileum. The traditional assessment from routine histological observation was compared with OCT captured using a handheld surgical probe during the days post-transplant and subsequently was compared with histophaology. RESULTS: The reported OCT system was capable of identifying major biological landmarks in healthy intestinal tissue. Following IT, one nonhuman primate (NHP) model suffered a severe graft ischemia, and the second NHP graft failed due to acute cellular rejection. OCT images show visual evidence of correspondence with histological signs of IT rejection. CONCLUSIONS: Results suggest that OCT imaging has significant potential to reveal morphological changes associated with IT rejection and to improve patient outcomes overall.


Assuntos
Endoscopia , Tomografia de Coerência Óptica , Aloenxertos , Animais , Biópsia , Macaca mulatta
9.
Nat Commun ; 12(1): 5456, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526511

RESUMO

Sensitized kidney transplant recipients experience high rates of antibody-mediated rejection due to the presence of donor-specific antibodies and immunologic memory. Here we show that transient peri-transplant treatment with the central complement component C3 inhibitor Cp40 significantly prolongs median allograft survival in a sensitized nonhuman primate model. Despite donor-specific antibody levels remaining high, fifty percent of Cp40-treated primates maintain normal kidney function beyond the last day of treatment. Interestingly, presence of antibodies of the IgM class associates with reduced median graft survival (8 vs. 40 days; p = 0.02). Cp40 does not alter lymphocyte depletion by rhesus-specific anti-thymocyte globulin, but inhibits lymphocyte activation and proliferation, resulting in reduced antibody-mediated injury and complement deposition. In summary, Cp40 prevents acute antibody-mediated rejection and prolongs graft survival in primates, and inhibits T and B cell activation and proliferation, suggesting an immunomodulatory effect beyond its direct impact on antibody-mediated injury.


Assuntos
Anticorpos/imunologia , Complemento C3/antagonistas & inibidores , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Transplante de Rim/métodos , Macaca mulatta/imunologia , Piridonas/farmacologia , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Proliferação de Células/efeitos dos fármacos , Complemento C3/imunologia , Complemento C3/metabolismo , Citocinas/sangue , Citocinas/imunologia , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/metabolismo , Sobrevivência de Enxerto/imunologia , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Transplante Homólogo
10.
Hepatol Commun ; 5(9): 1527-1542, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34510831

RESUMO

Normothermic machine perfusion (NMP) provides clinicians an opportunity to assess marginal livers before transplantation. However, objective criteria and point-of-care (POC) biomarkers to predict risk and guide decision making are lacking. In this investigation, we characterized trends in POC biomarkers during NMP and compared primate donation after circulatory death (DCD) livers with short and prolonged warm ischemic injury. Following asystole, livers were subjected to either 5 minutes (DCD-5min, n = 4) or 45 minutes (DCD-45min, n = 4) of warm ischemia time. Livers were flushed with heparinized UW solution, and preserved in cold storage before NMP. During flow-controlled NMP, circulating perfusate and tissue biopsies were collected at 0, 2, 4, 6, and 8 hours for analysis. DCD-45min livers had greater terminal portal vein pressure (8.5 vs. 13.3 mm Hg, P = 0.027) and terminal portal vein resistance (16.3 vs. 32.4 Wood units, P = 0.005). During perfusion, DCD-45min livers had equivalent terminal lactate clearance (93% vs. 96%, P = 0.344), greater terminal alanine aminotransferase (163 vs. 883 U/L, P = 0.002), and greater terminal perfusate gamma glutamyltransferase (GGT) (5.0 vs. 31.7 U/L, P = 0.002). DCD-45min livers had higher circulating levels of flavin mononucleotide (FMN) at hours 2 and 4 of perfusion (136 vs. 250 ng/mL, P = 0.029; and 158 vs. 293 ng/mL, P = 0.003; respectively). DCD-5min livers produced more bile and demonstrated progressive decline in bile lactate dehydrogenase, whereas DCD-45min livers did not. On blinded histologic evaluation, DCD-45min livers demonstrated greater injury and necrosis at late stages of perfusion, indicative of nonviability. Conclusion: Objective criteria are needed to define graft viability during NMP. Perfusate lactate clearance does not discriminate between viable and nonviable livers during NMP. Perfusate GGT and FMN may represent POC biomarkers predictive of liver injury during NMP.

11.
Front Immunol ; 12: 660900, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149698

RESUMO

Background: In transplantation, plasmapheresis and IVIg provide the mainstay of treatment directed at reducing or removing circulating donor-specific antibody (DSA), yet both have limitations. We sought to test the efficacy of targeting the IgG recycling mechanism of the neonatal Fc receptor (FcRn) using anti-FcRn mAb therapy in a sensitized non-human primate (NHP) model, as a pharmacological means of lowering DSA. Methods: Six (6) rhesus macaque monkeys, previously sensitized by skin transplantation, received a single dose of 30mg/kg anti-RhFcRn IV, and effects on total IgG, as well as DSA IgG, were measured, in addition to IgM and protective immunity. Subsequently, 60mg/kg IV was given in the setting of kidney transplantation from skin graft donors. Kidney transplant recipients received RhATG, and tacrolimus, MMF, and steroid for maintenance immunosuppression. Results: Circulating total IgG was reduced from a baseline 100% on D0 to 32.0% (mean, SD ± 10.6) on d4 post infusion (p<0.05), while using a DSA assay. T-cell flow cross match (TFXM) was reduced to 40.6±12.5% of baseline, and B-cell FXCM to 52.2±19.3%. Circulating total IgM and DSA IgM were unaffected by treatment. Pathogen-specific antibodies (anti-gB and anti-tetanus toxin IgG) were significantly reduced for 14d post infusion. Post-transplant, circulating IgG responded to anti-FcRn mAb treatment, but DSA increased rapidly. Conclusion: Targeting the FcRn-mediated recycling of IgG is an effective means of lowering circulating donor-specific IgG in the sensitized recipient, although in the setting of organ transplantation mechanisms of rapid antibody rise post-transplant remains unaffected.


Assuntos
Antígenos de Histocompatibilidade Classe I/imunologia , Imunoglobulina G/imunologia , Imunoglobulinas Intravenosas/uso terapêutico , Isoanticorpos/imunologia , Receptores Fc/imunologia , Doadores de Tecidos , Animais , Anticorpos Monoclonais/uso terapêutico , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto , Teste de Histocompatibilidade , Imunoglobulina G/sangue , Terapia de Imunossupressão , Imunossupressores/administração & dosagem , Transplante de Rim , Macaca mulatta , Masculino , Modelos Animais
12.
Hepatobiliary Surg Nutr ; 10(3): 315-324, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34159159

RESUMO

BACKGROUND: Selection of the optimal treatment modality for primary liver cancers remains complex, balancing patient condition, liver function, and extent of disease. In individuals with preserved liver function, liver resection remains the primary approach for treatment with curative intent but may be associated with significant mortality. The purpose of this study was to establish a simple scoring system based on Model for End-stage Liver Disease (MELD) and extent of resection to guide risk assessment for liver resections. METHODS: The 2005-2015 NSQIP database was queried for patients undergoing liver resection for primary liver malignancy. We first developed a model that incorporated the extent of resection (1 point for major hepatectomy) and a MELD-Na score category of low (MELD-Na =6, 1 point), medium (MELD-Na =7-10, 2 points) or high (MELD-Na >10, 3 points) with a score range of 1-4, called the Hepatic Resection Risk Score (HeRS). We tested the predictive value of this model on the dataset using logistic regression. We next developed an optimal multivariable model using backwards sequential selection of variables under logistic regression. We performed K-fold cross validation on both models. Receiver operating characteristics were plotted and the optimal sensitivity and specificity for each model were calculated to obtain positive and negative predictive values. RESULTS: A total of 4,510 patients were included. HeRS was associated with increased odds of 30-day mortality [HeRS =2: OR =3.23 (1.16-8.99), P=0.025; HeRS =3: OR =6.54 (2.39-17.90), P<0.001; HeRS =4: OR =13.69 (4.90-38.22), P<0.001]. The AUC for this model was 0.66. The AUC for the optimal multivariable model was higher at 0.76. Under K-fold cross validation, the positive predictive value (PPV) and negative predictive value (NPV) of these two models were similar at PPV =6.4% and NPV =97.7% for the HeRS only model and PPV =8.4% and NPV =98.1% for the optimal multivariable model. CONCLUSIONS: The HeRS offers a simple heuristic for estimating 30-day mortality after resection of primary liver malignancy. More complicated models offer better performance but at the expense of being more difficult to integrate into clinical practice.

13.
HPB (Oxford) ; 23(12): 1906-1913, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34154924

RESUMO

BACKGROUND: The aim of the present study was to evaluate the impact of routine NGT decompression after PD on postoperative outcomes in the era of an enhanced recovery after surgery (ERAS) protocol. MATERIALS AND METHODS: A retrospective review of all patients undergoing PD between January 2015 and October 2017 at our institution was performed comparing routine post-operative NGT decompression versus omission. The incidence of delayed gastric emptying, post-operative pancreatic fistula, hospital length of stay, operative time, 30-day readmission rate as well the time to first oral intake were evaluated. RESULTS: Out of 149 patients who underwent PD, 65 maintained post-operative NGT decompression while post-operative NGT decompression was omitted in 84 patients. No differences were noted in delayed gastric emptying rates (both p>0.05). The median length of stay (9 days for NGT group versus 8.5 days for no NGT group) and 30-day readmission rates (13.8% versus 15.5%, respectively) were similar (p=0.781). Compared with patients who had routine post-operative NGT placed, those who had omission of a post-operative NGT had a lower need for reinsertion, shorter time to PO intake, and a lower likelihood of extended length of stay. CONCLUSIONS: In the era of ERAS protocols, we observed no association between routine post-operative NGT decompression after PD and improved postoperative outcomes.


Assuntos
Intubação Gastrointestinal , Pancreaticoduodenectomia , Descompressão/efeitos adversos , Humanos , Tempo de Internação , Fístula Pancreática , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
14.
Am J Transplant ; 21(9): 3163-3174, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33942491

RESUMO

Thymic output and homeostatic mature cell proliferation both influence T cell repopulation following depletional induction, though the relative contribution of each and their association with recipient age have not been well studied. We investigated the repopulating T cell kinetics in kidney transplant recipients who underwent alemtuzumab induction followed by belatacept/rapamycin-based immunosuppression over 36-month posttransplantation. We focused specifically on the correlation between repopulating T cell subsets and the age of patients. Substantial homeostatic Ki67-expressing T cell proliferation was seen posttransplantation. A repertoire enriched for naïve T (TNaïve ) cells emerged posttransplantation. Analysis by generalized estimating equation linear models revealed a strong negative linear association between reconstituting TNaïve cells and advancing age. A relationship between age and persistence of effector memory cells was shown. We assessed thymic output and found an increase in the frequency of recent thymic emigrants (RTEs, CD4+ CD31+ ) at 12-month posttransplantation. Patients under 30 years of age showed significantly higher levels of CD4+ CD31+ cells than patients over 55 years of age pre- and posttransplantation. IL-7 and autologous mature dendritic cells (mDCs) induced CD57- cell proliferation. In contrast, mDCs, but not IL-7, induced CD57+ cell proliferation. This study establishes the relationship between age and thymic output during T cell homeostatic repopulation after alemtuzumab induction. Trial Registration: ClinicalTrials.gov - NCT00565773.


Assuntos
Transplante de Rim , Abatacepte , Proliferação de Células , Humanos , Terapia de Imunossupressão , Pessoa de Meia-Idade , Transplantados
15.
Clin Transplant ; 35(8): e14369, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34021521

RESUMO

Rabbit antithymocyte globulin (RATG) preparations are widely used in transplantation. They are developed in vivo against thymocytes and contain polyclonal antibodies specific for myriad cellular targets. The rhesus monkey is commonly used as a preclinical transplant model, but the fidelity of commercially available human-specific RATGs to anticipate the effects of RATGs in rhesus has not been established. We therefore developed two rhesus-specific ATGs (rhATG) and compared them to human-specific RATG (huATG, Thymoglobulin® ) in rhesus monkeys, assessing the magnitude and phenotype of depletion peripherally and in lymph nodes. Four primates were assigned to each group and received 20 mg/kg of drug. Depletion, repopulation, and changes in lymphocyte subsets were evaluated in peripheral blood and lymph nodes by flow cytometry over four months. We observed similar qualitative changes in lymphocyte subsets, but a generally more profound depletion with huATG compared to either rhATG. Peripheral homeostatic proliferation rather than thymic output was the major mechanism for repopulation with all RATGs. Repopulation was slower but qualitatively similar when examining RATGs in additional animals receiving concomitant chronic immunosuppression. Depletional induction is similar to human- and rhesus-specific RATGs in rhesus macaques. Both rhesus- and human-specific agents appear appropriate for preclinical modeling of clinical RATG use.


Assuntos
Soro Antilinfocitário , Animais , Citometria de Fluxo , Humanos , Macaca mulatta
17.
Xenotransplantation ; 28(3): e12680, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33619844

RESUMO

BACKGROUND: Thrombosis is a known consequence of intraportal islet transplantation, particularly for xenogeneic islets. To define the origins of thrombosis after islet xenotransplantation and relate it to early inflammation, we examined porcine islets transplanted into non-human primates using a dual-transplant model to directly compare islet characteristics. METHODS: α1,3-Galactosyltransferase gene-knockout (GTKO) islets with and without expression of the human complement regulatory transgene CD46 (hCD46) were studied. Biologically inert polyethylene microspheres were used to examine the generic pro-thrombotic effects of particle embolization. Immunohistochemistry was performed 1 and 24 hours after transplantation. RESULTS: Xeno-islet transplantation activated both extrinsic and intrinsic coagulation pathways. The intrinsic pathway was also initiated by microsphere embolization, while extrinsic pathway tissue factor (TF) and platelet aggregation were more specific to engrafted islets. hCD46 expression significantly reduced TF, platelet, fibrin, and factor XIIIa accumulation in and around islets but did not alter intrinsic factor activation. Layers of TF+ cells emerged around islets within 24 hours, particularly co-localized with vimentin, and identified as CD3+ and CD68+ cells inflammatory cells. CONCLUSIONS: These findings detail the origins of thrombosis following islet xenotransplantation, relate it to early immune activation, and suggest a role for transgenic hCD46 expression in its mitigation. Layers of TF-positive inflammatory cells and fibroblasts around islets at 24 hours may have important roles in the progressive events of thrombosis, inflammatory cell recruitment, rejection, and the ultimate outcome of transplanted grafts. These suggest that the strategies targeting these elements could yield more progress toward successful xenogeneic islet engraftment and survival.


Assuntos
Transplante das Ilhotas Pancreáticas , Animais , Xenoenxertos , Inflamação , Suínos , Transgenes , Transplante Heterólogo
18.
World J Surg ; 45(5): 1504-1513, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33486584

RESUMO

BACKGROUND: "Textbook outcome" (TO) is a novel composite quality measure that encompasses multiple postoperative endpoints, representing the ideal "textbook" hospitalization for complex surgical procedures. We defined TO for kidney transplantation using a cohort from a high-volume institution. METHODS: Adult patients who underwent isolated kidney transplantation at our institution between 2016 and 2019 were included. TO was defined by clinician consensus at our institution to include freedom from intraoperative complication, postoperative reintervention, 30-day intensive care unit or hospital readmission, length of stay > 75th percentile of kidney transplant patients, 90-day mortality, 30-day acute rejection, delayed graft function, and discharge with a Foley catheter. Recipient, operative, financial characteristics, and post-transplant patient, graft, and rejection-free survival were compared between patients who achieved and failed to achieve TO. RESULTS: A total of 557 kidney transplant patients were included. Of those, 245 (44%) achieved TO. The most common reasons for TO failure were delayed graft function (N = 157, 50%) and hospital readmission within 30 days (N = 155, 50%); the least common was mortality within 90 days (N = 6, 2%). Patient, graft, and rejection-free survival were significantly improved among patients who achieved TO. On average, patients who achieved TO incurred approximately $50,000 less in total inpatient charges compared to those who failed TO. CONCLUSIONS: TO in kidney transplantation was associated with favorable post-transplant outcomes and significant cost-savings. TO may offer transplant centers a detailed performance breakdown to identify aspects of perioperative care in need of process improvement.


Assuntos
Transplante de Rim , Adulto , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Readmissão do Paciente , Assistência Perioperatória , Indicadores de Qualidade em Assistência à Saúde , Estudos Retrospectivos
19.
Ann Surg Oncol ; 28(1): 114-120, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32556871

RESUMO

BACKGROUND: This study aimed to determine whether postoperative chemotherapy is associated with a survival benefit for patients with poorly differentiated neuroendocrine carcinoma (NEC) of the stomach, small bowel, or pancreas. METHODS: Patients were identified in the National Cancer Database (NCDB) between 2004 and 2014. Inverse probability of treatment weighting (IPTW) was used to reduce selection bias. To compare the overall survival (OS) of patients in different treatment groups, IPTW-adjusted Kaplan-Meier curves and Cox proportional hazards models were used. RESULTS: The inclusion criteria were met by 759 patients. The diagnosis was NEC of the stomach for 195 patients (25.7%), NEC of the small intestine for 278 patients (36.6%), and NEC of the pancreas for 286 patients (37.7%). Overall, 213 patients (28.1%) received postoperative chemotherapy after curative resection. For the patients who received chemotherapy, IPTW-adjusted survival showed no OS benefit. However, subgroup analysis demonstrated improved OS with observation (OB) for patients with NEC of the small intestine (hazard ratio [HR], 1.436; 95% confidence interval [CI] 1.13-1.823; P = 0.003), T3 or T4 primary tumor (HR, 1.258; 95% CI 1.08-1.465; P = 0.003), node-positive disease (HR, 1.238; 95% CI 1.040-1.475; P = 0.0165), or positive resection margin (HR, 1.4283; 95% CI 1.02-2.00; P = 0.038). CONCLUSIONS: In this national database analysis, postoperative chemotherapy was not associated with improved survival for patients with poorly differentiated gastroenteropancreatic (GEP) NECs. These findings highlight the need for continued efforts to understand better which patients in this high-risk population will benefit from additional systemic therapy and the need for continued development of more effective therapies for these patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Carcinoma Neuroendócrino , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Neuroendócrino/tratamento farmacológico , Carcinoma Neuroendócrino/cirurgia , Humanos , Recém-Nascido , Período Pós-Operatório , Modelos de Riscos Proporcionais , Estudos Retrospectivos
20.
Exp Clin Transplant ; 19(1): 92-93, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32490764

RESUMO

Pancreatic neuroendocrine tumors are a rare type of tumor with malignant potential, characterized by slowgrowth, frequent hepatic metastatic lesions that usually stay contained within the liver. In patients with unresectable liver metastatic pancreatic neuroendocrine tumors, liver transplant is the only treatment available. Insulinomas are the most common pancreatic neuroendocrine tumors, and 5% to 10% of insulinomas are malignant. We herein report a case of a living-donor liver transplant with distal pancreatectomy for a patient with hepatic metastatic pancreatic insulinoma with a 13-year postoperative survival.


Assuntos
Transplante de Rim , Listas de Espera , Humanos , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade
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