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1.
Am J Transplant ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38447887

RESUMO

Posttransplant lymphoproliferative disorder (PTLD) poses a significant concern in Epstein-Barr virus (EBV)-negative patients transplanted from EBV-positive donors (EBV R-/D+). Previous studies investigating the association between different induction agents and PTLD in these patients have yielded conflicting results. Using the Organ Procurement and Transplant Network database, we identified EBV R-/D+ patients >18 years of age who underwent kidney-alone transplants between 2016 and 2022 and compared the risk of PTLD with rabbit antithymocyte globulin (ATG), basiliximab, and alemtuzumab inductions. Among the 6620 patients included, 64.0% received ATG, 23.4% received basiliximab, and 12.6% received alemtuzumab. The overall incidence of PTLD was 2.5% over a median follow-up period of 2.9 years. Multivariable analysis demonstrated that the risk of PTLD was significantly higher with ATG and alemtuzumab compared with basiliximab (adjusted subdistribution hazard ratio [aSHR] = 1.98, 95% confidence interval [CI] 1.29-3.04, P = .002 for ATG and aSHR = 1.80, 95% CI 1.04-3.11, P = .04 for alemtuzumab). However, PTLD risk was comparable between ATG and alemtuzumab inductions (aSHR = 1.13, 95% CI 0.72-1.77, P = .61). Therefore, the risk of PTLD must be taken into consideration when selecting the most appropriate induction therapy for this patient population.

2.
Liver Transpl ; 29(12): 1282-1291, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37040930

RESUMO

In situ abdominal normothermic regional perfusion (A-NRP) has been used for liver transplantation (LT) with donation after circulatory death (DCD) liver grafts in Europe with excellent results; however, adoption of A-NRP in the United States has been lacking. The current report describes the implementation and results of a portable, self-reliant A-NRP program in the United States. Isolated abdominal in situ perfusion with an extracorporeal circuit was achieved through cannulation in the abdomen or femoral vessels and inflation of a supraceliac aortic balloon and cross-clamp. The Quantum Transport System by Spectrum was used. The decision to use livers for LT was made through an assessment of perfusate lactate (q15min). From May to November 2022, 14 A-NRP donation after circulatory death procurements were performed by our abdominal transplant team (N = 11 LT, N = 20 kidney transplants, and 1 kidney-pancreas transplant). The median A-NRP run time was 68 minutes. None of the LT recipients had post-reperfusion syndrome, nor were there any cases of primary nonfunction. All livers were functioning well at the time of maximal follow-up with zero cases of ischemic cholangiopathy. The current report describes the feasibility of a portable A-NRP program that can be used in the United States. Excellent short-term post-transplant results were achieved with both livers and kidneys procured from A-NRP.


Assuntos
Transplante de Fígado , Preservação de Órgãos , Humanos , Estados Unidos , Preservação de Órgãos/métodos , Doadores de Tecidos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Sobrevivência de Enxerto , Perfusão/métodos , Abdome
3.
Clin Transplant ; 37(5): e14943, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36799718

RESUMO

BACKGROUND: Our study aimed to characterize kidney retransplant recipients using an unsupervised machine-learning approach. METHODS: We performed consensus cluster analysis based on the recipient-, donor-, and transplant-related characteristics in 17 443 kidney retransplant recipients in the OPTN/UNOS database from 2010 to 2019. We identified each cluster's key characteristics using the standardized mean difference of >.3. We compared the posttransplant outcomes, including death-censored graft failure and patient death among the assigned clusters RESULTS: Consensus cluster analysis identified three distinct clusters of kidney retransplant recipients. Cluster 1 recipients were predominantly white and were less sensitized. They were most likely to receive a living donor kidney transplant and more likely to be preemptive (30%) or need ≤1 year of dialysis (32%). In contrast, cluster 2 recipients were the most sensitized (median PRA 95%). They were more likely to have been on dialysis >1 year, and receive a nationally allocated, low HLA mismatch, standard KDPI deceased donor kidney. Recipients in cluster 3 were more likely to be minorities (37% Black; 15% Hispanic). They were moderately sensitized with a median PRA of 87% and were also most likely to have been on dialysis >1 year. They received locally allocated high HLA mismatch kidneys from standard KDPI deceased donors. Thymoglobulin was the most commonly used induction agent for all three clusters. Cluster 1 had the most favorable patient and graft survival, while cluster 3 had the worst patient and graft survival. CONCLUSION: The use of an unsupervised machine learning approach characterized kidney retransplant recipients into three clinically distinct clusters with differing posttransplant outcomes. Recipients with moderate allosensitization, such as those represented in cluster 3, are perhaps more disadvantaged in the kidney retransplantation process. Potential opportunities for improvement specific to these re-transplant recipients include working to improve opportunities to improve access to living donor kidney transplantation, living donor paired exchange and identifying strategies for better HLA matching.


Assuntos
Obtenção de Tecidos e Órgãos , Humanos , Consenso , Doadores de Tecidos , Doadores Vivos , Sobrevivência de Enxerto , Análise por Conglomerados , Aprendizado de Máquina , Rim
4.
Ren Fail ; 45(2): 2292163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38087474

RESUMO

BACKGROUND: Educational attainment significantly influences post-transplant outcomes in kidney transplant patients. However, research on specific attributes of lower-educated subgroups remains underexplored. This study utilized unsupervised machine learning to segment kidney transplant recipients based on education, further analyzing the relationship between these segments and post-transplant results. METHODS: Using the OPTN/UNOS 2017-2019 data, consensus clustering was applied to 20,474 kidney transplant recipients, all below a college/university educational threshold. The analysis concentrated on recipient, donor, and transplant features, aiming to discern pivotal attributes for each cluster and compare post-transplant results. RESULTS: Four distinct clusters emerged. Cluster 1 comprised younger, non-diabetic, first-time recipients from non-hypertensive younger donors. Cluster 2 predominantly included white patients receiving their first-time kidney transplant either preemptively or within three years, mainly from living donors. Cluster 3 included younger re-transplant recipients, marked by elevated PRA, fewer HLA mismatches. In contrast, Cluster 4 captured older, diabetic patients transplanted after prolonged dialysis duration, primarily from lower-grade donors. Interestingly, Cluster 2 showcased the most favorable post-transplant outcomes. Conversely, Clusters 1, 3, and 4 revealed heightened risks for graft failure and mortality in comparison. CONCLUSIONS: Through unsupervised machine learning, this study proficiently categorized kidney recipients with lesser education into four distinct clusters. Notably, the standout performance of Cluster 2 provides invaluable insights, underscoring the necessity for adept risk assessment and tailored transplant strategies, potentially elevating care standards for this patient cohort.


Assuntos
Transplante de Rim , Obtenção de Tecidos e Órgãos , Humanos , Transplantados , Sobrevivência de Enxerto , Doadores Vivos , Escolaridade , Aprendizado de Máquina , Rejeição de Enxerto/prevenção & controle
5.
Medicina (Kaunas) ; 59(5)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37241209

RESUMO

Background and Objectives: The aim of our study was to categorize very highly sensitized kidney transplant recipients with pre-transplant panel reactive antibody (PRA) ≥ 98% using an unsupervised machine learning approach as clinical outcomes for this population are inferior, despite receiving increased allocation priority. Identifying subgroups with higher risks for inferior outcomes is essential to guide individualized management strategies for these vulnerable recipients. Materials and Methods: To achieve this, we analyzed the Organ Procurement and Transplantation Network (OPTN)/United Network for Organ Sharing (UNOS) database from 2010 to 2019 and performed consensus cluster analysis based on the recipient-, donor-, and transplant-related characteristics in 7458 kidney transplant patients with pre-transplant PRA ≥ 98%. The key characteristics of each cluster were identified by calculating the standardized mean difference. The post-transplant outcomes were compared between the assigned clusters. Results: We identified two distinct clusters and compared the post-transplant outcomes among the assigned clusters of very highly sensitized kidney transplant patients. Cluster 1 patients were younger (median age 45 years), male predominant, and more likely to have previously undergone a kidney transplant, but had less diabetic kidney disease. Cluster 2 recipients were older (median 54 years), female predominant, and more likely to be undergoing a first-time transplant. While patient survival was comparable between the two clusters, cluster 1 had lower death-censored graft survival and higher acute rejection compared to cluster 2. Conclusions: The unsupervised machine learning approach categorized very highly sensitized kidney transplant patients into two clinically distinct clusters with differing post-transplant outcomes. A better understanding of these clinically distinct subgroups may assist the transplant community in developing individualized care strategies and improving the outcomes for very highly sensitized kidney transplant patients.


Assuntos
Transplante de Rim , Obtenção de Tecidos e Órgãos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Consenso , Rejeição de Enxerto , Análise por Conglomerados , Aprendizado de Máquina , Estudos Retrospectivos
6.
Medicina (Kaunas) ; 58(12)2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36557033

RESUMO

Background and Objectives: Our study aimed to cluster dual kidney transplant recipients using an unsupervised machine learning approach to characterize donors and recipients better and to compare the survival outcomes across these various clusters. Materials and Methods: We performed consensus cluster analysis based on recipient-, donor-, and transplant-related characteristics in 2821 dual kidney transplant recipients from 2010 to 2019 in the OPTN/UNOS database. We determined the important characteristics of each assigned cluster and compared the post-transplant outcomes between clusters. Results: Two clinically distinct clusters were identified by consensus cluster analysis. Cluster 1 patients was characterized by younger patients (mean recipient age 49 ± 13 years) who received dual kidney transplant from pediatric (mean donor age 3 ± 8 years) non-expanded criteria deceased donor (100% non-ECD). In contrast, Cluster 2 patients were characterized by older patients (mean recipient age 63 ± 9 years) who received dual kidney transplant from adult (mean donor age 59 ± 11 years) donor with high kidney donor profile index (KDPI) score (59% had KDPI ≥ 85). Cluster 1 had higher patient survival (98.0% vs. 94.6% at 1 year, and 92.1% vs. 76.3% at 5 years), and lower acute rejection (4.2% vs. 6.1% within 1 year), when compared to cluster 2. Death-censored graft survival was comparable between two groups (93.5% vs. 94.9% at 1 year, and 89.2% vs. 84.8% at 5 years). Conclusions: In summary, DKT in the United States remains uncommon. Two clusters, based on specific recipient and donor characteristics, were identified through an unsupervised machine learning approach. Despite varying differences in donor and recipient age between the two clusters, death-censored graft survival was excellent and comparable. Broader utilization of DKT from high KDPI kidneys and pediatric en bloc kidneys should be encouraged to better address the ongoing organ shortage.


Assuntos
Transplante de Rim , Estados Unidos/epidemiologia , Consenso , Estudos Retrospectivos , Rim , Aprendizado de Máquina
7.
Am J Transplant ; 21(2): 846-853, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33128832

RESUMO

This study utilized the UNOS database to assess clinical outcomes after kidney retransplantation in patients with a history of posttransplant lymphoproliferative disease (PTLD). Among second kidney transplant patients from 2000 to 2019, 254 had history of PTLD in their first kidney transplant, whereas 28,113 did not. After a second kidney transplant, PTLD occurred in 2.8% and 0.8% of patients with and without history of PTLD, respectively (p = .001). Over a median follow-up time of 4.5 years after a second kidney transplant, 5-year death-censored graft failure was 9.5% vs. 12.6% (p = .21), all-cause mortality was 8.3% vs. 11.8% (p = .51), and 1-year acute rejection was 11.0% vs. 9.3% (p = .36) in the PTLD vs. non-PTLD groups, respectively. There was no significant difference in death-censored graft failure, mortality, and acute rejection between PTLD and non-PTLD groups in adjusted analysis and after propensity score matching. We conclude that graft survival, patient survival, and acute rejection after kidney retransplantation are comparable between patients with and without history of PTLD, but PTLD occurrence after kidney retransplantation remains higher in patients with history of PTLD.


Assuntos
Transplante de Rim , Transtornos Linfoproliferativos , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Rim , Transplante de Rim/efeitos adversos , Transtornos Linfoproliferativos/epidemiologia , Transtornos Linfoproliferativos/etiologia , Reoperação , Fatores de Risco
8.
Liver Transpl ; 27(9): 1291-1301, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33687745

RESUMO

Pre-liver transplantation (LT) renal dysfunction is associated with poor post-LT survival. We studied whether early allograft dysfunction (EAD) modifies this association. Data on 2,856 primary LT recipients who received a transplant between 1998 and 2018 were retrospectively reviewed. Patients who died within the first post-LT week or received multiorgan transplants and previous LT recipients were excluded. EAD was defined as (1) total bilirubin ≥ 10 mg/dL on postoperative day (POD) 7, (2) international normalized ratio ≥1.6 on POD 7, and/or (3) alanine aminotransferase or aspartate aminotransferase ≥2000 IU/mL in the first postoperative week. Pre-LT renal dysfunction was defined as serum creatinine >1.5 mg/dL or on renal replacement therapy at LT. Patients were divided into 4 groups according to pre-LT renal dysfunction and post-LT EAD development. Recipients who had both pre-LT renal dysfunction and post-LT EAD had the worst unadjusted 1-year, 3-year, and 5-year post-LT patient and graft survival, whereas patients who had neither renal dysfunction nor EAD had the best survival (P < 0.001). After adjusting for multiple factors, the risk of death was significantly higher only in those with both pre-LT renal dysfunction and post-LT EAD (adjusted hazard ratio [aHR], 2.19; 95% confidence interval [CI], 1.58-3.03; P < 0.001), whereas those with renal dysfunction and no EAD had a comparable risk of death to those with normal kidney function at LT (aHR, 1.12; 95% CI, 0.86-1.45; P = 0.41). Results remained unchanged when pre-LT renal dysfunction was redefined using different glomerular filtration rate cutoffs. Pre-LT renal dysfunction negatively impacts post-LT survival only in patients who develop EAD. Livers at higher risk of post-LT EAD should be used with caution in recipients with pre-LT renal dysfunction.


Assuntos
Nefropatias , Transplante de Fígado , Aloenxertos , Sobrevivência de Enxerto , Humanos , Rim , Fígado , Transplante de Fígado/efeitos adversos , Estudos Retrospectivos , Fatores de Risco
9.
Ann Hepatol ; 24: 100317, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33545403

RESUMO

INTRODUCTION AND OBJECTIVES: Renal dysfunction before liver transplantation (LT) is associated with higher post-LT mortality. We aimed to study if this association still persisted in the contemporary transplant era. MATERIALS AND METHODS: We retrospectively reviewed data on 2871 primary LT performed at our center from 1998 to 2018. All patients were listed for LT alone and were not considered to be simultaneous liver-kidney (SLK) transplant candidates. SLK recipients and those with previous LT were excluded. Patients were grouped into 4 eras: era-1 (1998-2002, n = 488), era-2 (2003-2007, n = 889), era-3 (2008-2012, n = 703) and era-4 (2013-2018, n = 791). Pre-LT renal dysfunction was defined as creatinine (Cr) >1.5 mg/dl or on dialysis at LT. The effect of pre-LT renal dysfunction on post-LT patient survival in each era was examined using Kaplan Meier estimates and univariate and multivariate Cox proportional hazard analyses. RESULTS: Pre-LT renal dysfunction was present in 594 (20%) recipients. Compared to patients in era-1, patients in era-4 had higher Cr, lower eGFR and were more likely to be on dialysis at LT (P < 0.001). Pre-LT renal dysfunction was associated with worse 1, 3 and 5-year survival in era-1 and era-2 (P < 0.005) but not in era-3 or era-4 (P = 0.13 and P = 0.08, respectively). Multivariate analysis demonstrated the lack of independent effect of pre-LT renal dysfunction on post-LT mortality in era-3 and era-4. A separate analysis using eGFR <60 mL/min/1.73 m2 at LT to define renal dysfunction showed similar results. CONCLUSIONS: Pre-LT renal dysfunction had less impact on post-LT survival in the contemporary transplant era.


Assuntos
Hepatopatias/complicações , Hepatopatias/mortalidade , Transplante de Fígado , Insuficiência Renal/complicações , Idoso , Creatinina/sangue , Feminino , Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Humanos , Estimativa de Kaplan-Meier , Hepatopatias/cirurgia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Diálise Renal , Insuficiência Renal/diagnóstico , Insuficiência Renal/mortalidade , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Fatores de Tempo
10.
Am J Pathol ; 187(1): 33-41, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27855279

RESUMO

Hereditary tyrosinemia type 1 (HT1) is an autosomal recessive disease caused by deficiency in fumarylacetoacetate hydrolase, the last enzyme in the tyrosine catabolic pathway. In this study, we investigated whether fumarylacetoacetate hydrolase deficient (FAH-/-) pigs, a novel large-animal model of HT1, develop fibrosis and cirrhosis characteristic of the human disease. FAH-/- pigs were treated with the protective drug 2-(2-nitro-4-trifluoromethylbenzoyl)-1, 3 cyclohexandione (NTBC) at a dose of 1 mg/kg per day initially after birth. After 30 days, they were assigned to one of three groups based on dosing of NTBC. Group 1 received ≥0.2 mg/kg per day, group 2 cycled on/off NTBC (0.05 mg/kg per day × 1 week/0 mg/kg per day × 3 weeks), and group 3 received no NTBC thereafter. Pigs were monitored for features of liver disease. Animals in group 1 continued to have weight gain and biochemical analyses comparable to wild-type pigs. Animals in group 2 had significant cessation of weight gain, abnormal biochemical test results, and various grades of fibrosis and cirrhosis. No evidence of hepatocellular carcinoma was detected. Group 3 animals declined rapidly, with acute liver failure. In conclusion, the FAH-/- pig is a large-animal model of HT1 with clinical characteristics that resemble the human phenotype. Under conditions of low-dose NTBC, FAH-/- pigs developed liver fibrosis and portal hypertension, and thus may serve as a large-animal model of chronic liver disease.


Assuntos
Tirosinemias/patologia , Animais , Doença Crônica , Modelos Animais de Doenças , Técnicas de Imagem por Elasticidade , Feminino , Heptanoatos/metabolismo , Humanos , Hidrolases/deficiência , Hidrolases/metabolismo , Rim/metabolismo , Rim/patologia , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática/patologia , Espectroscopia de Ressonância Magnética , Masculino , Redes e Vias Metabólicas , Fenótipo , Pressão na Veia Porta , Sus scrofa , Tirosina/metabolismo , Aumento de Peso
11.
Stem Cells ; 35(1): 42-50, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27641427

RESUMO

Donor organ shortage is the main limitation to liver transplantation as a treatment for end-stage liver disease and acute liver failure. Liver regenerative medicine may in the future offer an alternative form of therapy for these diseases, be it through cell transplantation, bioartificial liver (BAL) devices, or bioengineered whole organ liver transplantation. All three strategies have shown promising results in the past decade. However, before they are incorporated into widespread clinical practice, the ideal cell type for each treatment modality must be found, and an adequate amount of metabolically active, functional cells must be able to be produced. Research is ongoing in hepatocyte expansion techniques, use of xenogeneic cells, and differentiation of stem cell-derived hepatocyte-like cells (HLCs). HLCs are a few steps away from clinical application, but may be very useful in individualized drug development and toxicity testing, as well as disease modeling. Finally, safety concerns including tumorigenicity and xenozoonosis must also be addressed before cell transplantation, BAL devices, and bioengineered livers occupy their clinical niche. This review aims to highlight the most recent advances and provide an updated view of the current state of affairs in the field of liver regenerative medicine. Stem Cells 2017;35:42-50.


Assuntos
Bioengenharia/métodos , Hepatócitos/transplante , Regeneração Hepática/fisiologia , Fígado Artificial , Medicina Regenerativa/métodos , Animais , Hepatócitos/citologia , Humanos , Células-Tronco/citologia , Células-Tronco/metabolismo
12.
Radiology ; 284(3): 694-705, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28128707

RESUMO

Purpose To investigate the utility of magnetic resonance (MR) elastography-derived mechanical properties in the discrimination of hepatic inflammation and fibrosis in the early stages of chronic liver diseases. Materials and Methods All studies were approved by the institutional animal care and use committee. A total of 187 animals were studied, including 182 mice and five pigs. These animals represented five different liver diseases with a varying combination and extent of hepatic inflammation, fibrosis, congestion, and portal hypertension. Multifrequency three-dimensional MR elastography was performed, and shear stiffness, storage modulus, shear loss modulus, and damping ratio were calculated for all animals. Necroinflammation, fibrosis, and portal pressure were either histologically scored or biochemically and physically quantified in all animals. Two-sided Welch t tests were used to evaluate mean differences between disease and control groups. Spearman correlation analyses were used to evaluate the relationships between mechanical parameters and quantitative fibrosis extent (hydroxyproline concentration) and portal pressure. Results Liver stiffness and storage modulus increased with progressively developed fibrosis and portal hypertension (mean stiffness at 80 Hz and 48-week feeding, 0.51 kPa ± 0.12 in the steatohepatitis group vs 0.29 kPa ± 0.01 in the control group; P = .02). Damping ratio and shear loss modulus can be used to distinguish inflammation from fibrosis at early stages of disease, even before the development of histologically detectable necroinflammation and fibrosis (mean damping ratio at 80 Hz and 20-week feeding, 0.044 ± 0.012 in the steatohepatitis group vs 0.014 ± 0.008 in the control group; P < .001). Damping ratio and liver stiffness vary differently with respect to cause of portal hypertension (ie, congestion- or cirrhosis-induced hypertension). These differentiation abilities have frequency-dependent variations. Conclusion Liver stiffness and damping ratio measurements can extend hepatic MR elastography to potentially enable assessment of necroinflammatory, congestive, and fibrotic processes of chronic liver diseases. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Hepatite/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Animais , Tetracloreto de Carbono/toxicidade , Doença Hepática Crônica Induzida por Substâncias e Drogas/diagnóstico por imagem , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/fisiopatologia , Feminino , Hepatite/patologia , Hepatite/fisiopatologia , Fígado/patologia , Fígado/fisiopatologia , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Camundongos , Suínos
13.
Crit Care ; 21(1): 251, 2017 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-29047410

RESUMO

BACKGROUND: Kidney congestion is a common pathophysiologic pathway of acute kidney injury (AKI) in sepsis and heart failure. There is no noninvasive tool to measure kidney intracapsular pressure (KIP) directly. METHODS: We evaluated the correlation of KIP with kidney elasticity measured by ultrasound surface wave elastography (USWE). We directly measured transcatheter KIP in three pigs at baseline and after bolus infusion of normal saline, norepinephrine, vasopressin, dopamine, and fenoldopam; infiltration of 2-L peritoneal dialysis solution in the intra-abdominal space; and venous, arterial, and ureteral clamping. KIP was compared with USWE wave speed. RESULTS: Only intra-abdominal installation of peritoneal dialysis fluid was associated with significant change in KIP (mean (95% CI) increase, 3.7 (3.2-4.2)] mmHg; P < .001). Although intraperitoneal pressure and KIP did not differ under any experimental condition, bladder pressure was consistently and significantly greater than KIP under all circumstances (mean (95% CI) bladder pressure vs. KIP, 3.8 (2.9-4.) mmHg; P < .001). USWE wave speed significantly correlated with KIP (adjusted coefficient of determination, 0.71; P < .001). Estimate (95% CI) USWE speed for KIP prediction stayed significant after adjustment for KIP hypertension (-0.8 (- 1.4 to - 0.2) m/s; P = .008) whereas systolic and diastolic blood pressures were not significant predictors of KIP. CONCLUSIONS: In a pilot study of the swine model, we found ultrasound surface wave elastography speed is significantly correlated with transcatheter measurement of kidney intracapsular and intra-abdominal pressures, while bladder pressure overestimated kidney intracapsular pressure.


Assuntos
Cápsula Glomerular/fisiologia , Técnicas de Imagem por Elasticidade/métodos , Animais , Pressão Sanguínea/fisiologia , Modelos Animais de Doenças , Feminino , Rim/irrigação sanguínea , Diálise Peritoneal/métodos , Projetos Piloto , Suínos/fisiologia , Ultrassonografia/métodos
14.
J Hepatol ; 63(2): 388-98, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25817557

RESUMO

BACKGROUND & AIMS: The neuroprotective effect of the spheroid reservoir bioartificial liver (SRBAL) was evaluated in a porcine model of drug-overdose acute liver failure (ALF). METHODS: Healthy pigs were randomized into three groups (standard therapy (ST) alone, ST+No-cell device, ST+SRBAL device) before placement of an implantable intracranial pressure (ICP) monitor and a tunneled central venous catheter. One week later, pigs received bolus infusion of the hepatotoxin D-galactosamine and were followed for up to 90h. RESULTS: At 48h, all animals had developed encephalopathy and biochemical changes confirming ALF; extracorporeal treatment was initiated and pigs were observed up to 90h after drug infusion. Pigs treated with the SRBAL, loaded with porcine hepatocyte spheroids, had improved survival (83%, n=6) compared to ST alone (0%, n=6, p=0.003) and No-cell device therapy (17%, n=6, p=0.02). Ammonia detoxification, peak levels of serum ammonia and peak ICP, and pig survival were influenced by hepatocyte cell dose, membrane pore size and duration of SRBAL treatment. Hepatocyte spheroids remained highly functional with no decline in mean oxygen consumption from initiation to completion of treatment. CONCLUSIONS: The SRBAL improved survival in an allogeneic model of drug-overdose ALF. Survival correlated with ammonia detoxification and ICP lowering indicating that hepatocyte spheroids prevented the cerebral manifestations of ALF (brain swelling, herniation, death). Further investigation of SRBAL therapy in a clinical setting is warranted.


Assuntos
Hepatócitos/citologia , Falência Hepática Aguda/terapia , Fígado Artificial , Esferoides Celulares , Engenharia Tecidual/métodos , Animais , Células Cultivadas , Modelos Animais de Doenças , Feminino , Suínos
15.
Liver Transpl ; 21(4): 442-53, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25482651

RESUMO

Cell transplantation is a potential treatment for the many liver disorders that are currently only curable by organ transplantation. However, one of the major limitations of hepatocyte (HC) transplantation is an inability to monitor cells longitudinally after injection. We hypothesized that the thyroidal sodium iodide symporter (NIS) gene could be used to visualize transplanted HCs in a rodent model of inherited liver disease: hereditary tyrosinemia type 1. Wild-type C57Bl/6J mouse HCs were transduced ex vivo with a lentiviral vector containing the mouse Slc5a5 (NIS) gene controlled by the thyroxine-binding globulin promoter. NIS-transduced cells could robustly concentrate radiolabeled iodine in vitro, with lentiviral transduction efficiencies greater than 80% achieved in the presence of dexamethasone. Next, NIS-transduced HCs were transplanted into congenic fumarylacetoacetate hydrolase knockout mice, and this resulted in the prevention of liver failure. NIS-transduced HCs were readily imaged in vivo by single-photon emission computed tomography, and this demonstrated for the first time noninvasive 3-dimensional imaging of regenerating tissue in individual animals over time. We also tested the efficacy of primary HC spheroids engrafted in the liver. With the NIS reporter, robust spheroid engraftment and survival could be detected longitudinally after direct parenchymal injection, and this thereby demonstrated a novel strategy for HC transplantation. This work is the first to demonstrate the efficacy of NIS imaging in the field of HC transplantation. We anticipate that NIS labeling will allow noninvasive and longitudinal identification of HCs and stem cells in future studies related to liver regeneration in small and large preclinical animal models.


Assuntos
Hepatócitos/transplante , Imageamento Tridimensional/métodos , Falência Hepática/prevenção & controle , Regeneração Hepática , Simportadores/metabolismo , Tomografia Computadorizada de Emissão de Fóton Único , Tirosinemias/cirurgia , Microtomografia por Raio-X , Animais , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Sobrevivência de Enxerto , Hepatócitos/metabolismo , Hidrolases/deficiência , Hidrolases/genética , Falência Hepática/diagnóstico , Falência Hepática/genética , Falência Hepática/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Imagem Multimodal , Valor Preditivo dos Testes , Simportadores/genética , Fatores de Tempo , Transdução Genética , Transfecção , Tirosinemias/diagnóstico , Tirosinemias/genética , Tirosinemias/metabolismo
16.
HPB (Oxford) ; 17(12): 1130-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26234167

RESUMO

BACKGROUND: Publications using the ALPPS (associating liver partition and portal vein ligation for a staged hepatectomy) procedure have demonstrated a future liver remnant growth of 40-160% in only 6-9 days. The present study aimed to develop and describe the first large animal model of ALPPS that can be used for future studies. METHODS: A total of 13 female domestic pigs underwent ALPPS stage 1 (portal vein division and parenchymal transection) followed by ALPPS stage 2 (completion left-extended hepatectomy) 7 days later. An abdominal computed tomography (CT) scan was performed immediately prior to ALPPS stage 1 surgery and again 7 days later to assess hypertrophy immediately prior to ALPPS stage 2 surgery. Blood samples, as well as tissue analysis for Ki-67, were performed. RESULTS: On CT volumetric analysis, the mean size of the future liver remnant (FLR) prior to ALPPS stage 1 was 21 ± 2% and 40 ± 6% prior to ALPPS stage 2. The median degree of growth was 75% with a mean kinetic growth rate of 11% per day. Liver weights at autopsy correlated well with CT volumetric analysis (r = 0.87). There was no significant difference in mean lab values [asparate aminotransferase (AST), alanine aminotransferase (ALT), ammonia, International Normalized Ratio (INR) or bilirubin] from baseline until immediately prior to ALPPS stage 2. Post ALPPS stage 2 there was a significant increase in INR from baseline 1.1 to 1.6 (P = 0.012). No post-operative deaths secondary to liver failure were observed. CONCLUSION: The present study describes the first reproducible large animal model of the ALPPS procedure. The degree of liver growth and the kinetic rate of growth were similar to that which has been demonstrated in human publications. This model will be valuable as future laboratory studies are performed.


Assuntos
Hepatectomia/métodos , Fígado/irrigação sanguínea , Fígado/cirurgia , Veia Porta/cirurgia , Procedimentos Cirúrgicos Vasculares , Animais , Biomarcadores/metabolismo , Proliferação de Células , Feminino , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Ligadura , Fígado/diagnóstico por imagem , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Regeneração Hepática , Modelos Animais , Tamanho do Órgão , Sus scrofa , Fatores de Tempo , Tomografia Computadorizada por Raios X
17.
Clin Pract ; 14(2): 590-601, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38666804

RESUMO

BACKGROUND: Pancreas transplantation is a crucial surgical intervention for managing diabetes, but it faces challenges such as its invasive nature, stringent patient selection criteria, organ scarcity, and centralized expertise. Despite the steadily increasing number of pancreas transplants in the United States, there is a need to understand global trends in interest to increase awareness of and participation in pancreas and islet cell transplantation. METHODS: We analyzed Google Search trends for "Pancreas Transplantation" and "Islet Cell Transplantation" from 2004 to 14 November 2023, assessing variations in search interest over time and across geographical locations. The Augmented Dickey-Fuller (ADF) test was used to determine the stationarity of the trends (p < 0.05). RESULTS: Search interest for "Pancreas Transplantation" varied from its 2004 baseline, with a general decline in peak interest over time. The lowest interest was in December 2010, with a slight increase by November 2023. Ecuador, Kuwait, and Saudi Arabia showed the highest search interest. "Islet Cell Transplantation" had its lowest interest in December 2016 and a more pronounced decline over time, with Poland, China, and South Korea having the highest search volumes. In the U.S., "Pancreas Transplantation" ranked 4th in interest, while "Islet Cell Transplantation" ranked 11th. The ADF test confirmed the stationarity of the search trends for both procedures. CONCLUSIONS: "Pancreas Transplantation" and "Islet Cell Transplantation" showed initial peaks in search interest followed by a general downtrend. The stationary search trends suggest a lack of significant fluctuations or cyclical variations. These findings highlight the need for enhanced educational initiatives to increase the understanding and awareness of these critical transplant procedures among the public and professionals.

18.
Transplant Proc ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38997885

RESUMO

INTRODUCTION: Despite the data demonstrating an increased utilization of hepatitis C virus (HCV)-viremic kidneys, the acceptance and incorporation of HCV-viremic kidneys are not universal. We aimed to identify regional differences and their temporal changes in the utilization of HCV-viremic kidneys. METHODS: Using the Organ Procurement and Transplantation Network database, HCV-viremic kidneys utilized in kidney transplants from March 15, 2019, to March 14, 2023, were included. The utilization of HCV-viremic kidneys across the United States and center-level clustering of HCV-viremic donor kidney transplants into HCV NAT-negative recipients (HCV D+/R- transplants) using Gini coefficients were examined. RESULTS: Significant regional variations were observed, with regions 3, 10, and 11 accounting for 51% of all HCV-viremic kidney utilization. Region 9 benefited the most from HCV-viremic kidney transplants with a high influx of kidney imports from other regions (284.9% gain). Region 8 and region 6 encountered the most substantial losses, with net losses of -44.2% and -41.1%, respectively. HCV D+/R- transplants were concentrated in specific high-volume centers, but trends indicated a gradual increase in a more equitable distribution across centers over time. CONCLUSIONS: Significant variations can be observed in the utilization of HCV-viremic kidneys throughout the United States. These variations highlight opportunities for kidney transplant centers in specific regions to adopt policies for HCV-viremic kidney transplants, thereby expanding their donor pool. Encouragingly, an increasing number of kidney transplant centers are adopting HCV D+/R- kidney transplants, indicating positive progress. These trends suggest a more balanced access to HCV-viremic kidneys ahead.

19.
Sci Rep ; 14(1): 8511, 2024 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609476

RESUMO

Health equity and accessing Spanish kidney transplant information continues being a substantial challenge facing the Hispanic community. This study evaluated ChatGPT's capabilities in translating 54 English kidney transplant frequently asked questions (FAQs) into Spanish using two versions of the AI model, GPT-3.5 and GPT-4.0. The FAQs included 19 from Organ Procurement and Transplantation Network (OPTN), 15 from National Health Service (NHS), and 20 from National Kidney Foundation (NKF). Two native Spanish-speaking nephrologists, both of whom are of Mexican heritage, scored the translations for linguistic accuracy and cultural sensitivity tailored to Hispanics using a 1-5 rubric. The inter-rater reliability of the evaluators, measured by Cohen's Kappa, was 0.85. Overall linguistic accuracy was 4.89 ± 0.31 for GPT-3.5 versus 4.94 ± 0.23 for GPT-4.0 (non-significant p = 0.23). Both versions scored 4.96 ± 0.19 in cultural sensitivity (p = 1.00). By source, GPT-3.5 linguistic accuracy was 4.84 ± 0.37 (OPTN), 4.93 ± 0.26 (NHS), 4.90 ± 0.31 (NKF). GPT-4.0 scored 4.95 ± 0.23 (OPTN), 4.93 ± 0.26 (NHS), 4.95 ± 0.22 (NKF). For cultural sensitivity, GPT-3.5 scored 4.95 ± 0.23 (OPTN), 4.93 ± 0.26 (NHS), 5.00 ± 0.00 (NKF), while GPT-4.0 scored 5.00 ± 0.00 (OPTN), 5.00 ± 0.00 (NHS), 4.90 ± 0.31 (NKF). These high linguistic and cultural sensitivity scores demonstrate Chat GPT effectively translated the English FAQs into Spanish across systems. The findings suggest Chat GPT's potential to promote health equity by improving Spanish access to essential kidney transplant information. Additional research should evaluate its medical translation capabilities across diverse contexts/languages. These English-to-Spanish translations may increase access to vital transplant information for underserved Spanish-speaking Hispanic patients.


Assuntos
Transplante de Rim , Humanos , Alanina Transaminase , Inteligência Artificial , Colina O-Acetiltransferase , Promoção da Saúde , Hispânico ou Latino , Reprodutibilidade dos Testes , Medicina Estatal , Americanos Mexicanos
20.
Front Digit Health ; 6: 1366967, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38659656

RESUMO

Background: Addressing disparities in living kidney donation requires making information accessible across literacy levels, especially important given that the average American adult reads at an 8th-grade level. This study evaluated the effectiveness of ChatGPT, an advanced AI language model, in simplifying living kidney donation information to an 8th-grade reading level or below. Methods: We used ChatGPT versions 3.5 and 4.0 to modify 27 questions and answers from Donate Life America, a key resource on living kidney donation. We measured the readability of both original and modified texts using the Flesch-Kincaid formula. A paired t-test was conducted to assess changes in readability levels, and a statistical comparison between the two ChatGPT versions was performed. Results: Originally, the FAQs had an average reading level of 9.6 ± 1.9. Post-modification, ChatGPT 3.5 achieved an average readability level of 7.72 ± 1.85, while ChatGPT 4.0 reached 4.30 ± 1.71, both with a p-value <0.001 indicating significant reduction. ChatGPT 3.5 made 59.26% of answers readable below 8th-grade level, whereas ChatGPT 4.0 did so for 96.30% of the texts. The grade level range for modified answers was 3.4-11.3 for ChatGPT 3.5 and 1-8.1 for ChatGPT 4.0. Conclusion: Both ChatGPT 3.5 and 4.0 effectively lowered the readability grade levels of complex medical information, with ChatGPT 4.0 being more effective. This suggests ChatGPT's potential role in promoting diversity and equity in living kidney donation, indicating scope for further refinement in making medical information more accessible.

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