Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 146
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Am J Transplant ; 18(3): 750-755, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28949067

RESUMEN

Replacement of pancreatic ß-cells through deceased donor islet transplantation is a proven therapy for preventing recurrent life-threatening hypoglycemia in type 1 diabetes. Although near-normal glucose levels and insulin independence can be maintained for many years following successful islet transplantation, restoration of normal functional ß-cell mass has remained elusive. It has recently been proposed that dedifferentiation/plasticity towards other endocrine phenotypes may play an important role in stress-induced ß-cell dysfunction in type 2 diabetes. Here we report loss of end-differentiated ß-cell phenotype in 2 intraportal islet allotransplant recipients. Despite excellent graft function and sustained insulin independence, all examined insulin-positive cells had lost expression of the end-differentiation marker, urocortin-3, or appeared to co-express the α-cell marker, glucagon. In contrast, no insulin+ /urocortin-3- cells were seen in nondiabetic deceased donor control pancreatic islets. Loss of end-differentiated phenotype may facilitate ß-cell survival during the stresses associated with islet isolation and culture, in addition to sustained hypoxia following engraftment. As further refinements in islet isolation and culture are made in parallel with exploration of alternative ß-cell sources, graft sites, and ultimately fully vascularized bioengineered insulin-secreting microtissues, differentiation status immunostaining provides a novel tool to assess whether fully mature ß-cell phenotype has been maintained.


Asunto(s)
Diferenciación Celular , Fibrosis Quística/terapia , Diabetes Mellitus Tipo 1/terapia , Células Secretoras de Insulina/patología , Trasplante de Islotes Pancreáticos/métodos , Adulto , Femenino , Humanos , Fenotipo , Pronóstico
2.
Am J Transplant ; 17(2): 462-473, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27343461

RESUMEN

Pancreatic islet grafting restores endogenous insulin production in type 1 diabetic patients, but long-term outcomes remain disappointing as a result of immunological destruction of allogeneic islets. In solid organ transplantation, donor-specific anti-HLA antibodies (DSA) are the first cause of organ failure. This retrospective multicentric study aimed at providing in-depth characterization of DSA response after pancreatic islet grafting, identifying the risk factor for DSA generation and determining the impact of DSA on graft function. Forty-two pancreatic islet graft recipients from the Groupe Rhin-Rhône-Alpes-Genève pour la Greffe d'Ilots de Langerhans consortium were enrolled. Pre- and postgrafting sera were screened for the presence of DSA and their ability to activate complement. Prevalence of DSA was 25% at 3 years postgrafting. The risk of sensitization increased steeply after immunosuppressive drug withdrawal. DSA repertoire diversity correlated with the number of HLA and eplet mismatches. DSA titer was significantly lower from that observed in solid organ transplantation. No detected DSA bound the complement fraction C3d. Finally, in contrast with solid organ transplantation, DSA did not seem to negatively affect pancreatic islet graft survival. This might be due to the low DSA titers, specific features of IgG limiting their ability to activate the complement and/or the lack of allogenic endothelial targets in pancreatic islet grafts.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Rechazo de Injerto/etiología , Supervivencia de Injerto/inmunología , Antígenos HLA/inmunología , Trasplante de Islotes Pancreáticos/efectos adversos , Isoanticuerpos/sangre , Donantes de Tejidos , Adulto , Femenino , Estudios de Seguimiento , Rechazo de Injerto/patología , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Receptores de Trasplantes
3.
Am J Transplant ; 16(8): 2473-8, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27109874

RESUMEN

Most countries exclude human immunodeficiency virus (HIV)-positive patients from organ donation because of concerns regarding donor-derived HIV transmission. The Swiss Federal Act on Transplantation has allowed organ transplantation between HIV-positive donors and recipients since 2007. We report the successful liver transplantation from an HIV-positive donor to an HIV-positive recipient. Both donor and recipient had been treated for many years with antiretroviral therapy and harbored multidrug-resistant viruses. Five months after transplantation, HIV viremia remains undetectable. This observation supports the inclusion of appropriate HIV-positive donors for transplants specifically allocated to HIV-positive recipients.


Asunto(s)
Supervivencia de Injerto/inmunología , Infecciones por VIH/cirugía , Seropositividad para VIH , VIH-1/inmunología , Trasplante de Hígado , Donantes de Tejidos/provisión & distribución , Obtención de Tejidos y Órganos , Anciano , Infecciones por VIH/virología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico
4.
Diabetes Obes Metab ; 18(4): 355-65, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26662378

RESUMEN

AIM: To determine the impact of a functional human islet clock on insulin secretion and gene transcription. METHODS: Efficient circadian clock disruption was achieved in human pancreatic islet cells by small interfering RNA-mediated knockdown of CLOCK. Human islet secretory function was assessed in the presence or absence of a functional circadian clock by stimulated insulin secretion assays, and by continuous around-the-clock monitoring of basal insulin secretion. Large-scale transcription analysis was accomplished by RNA sequencing, followed by quantitative RT-PCR analysis of selected targets. RESULTS: Circadian clock disruption resulted in a significant decrease in both acute and chronic glucose-stimulated insulin secretion. Moreover, basal insulin secretion by human islet cells synchronized in vitro exhibited a circadian pattern, which was perturbed upon clock disruption. RNA sequencing analysis suggested alterations in 352 transcript levels upon circadian clock disruption. Among them, key regulators of the insulin secretion pathway (GNAQ, ATP1A1, ATP5G2, KCNJ11) and transcripts required for granule maturation and release (VAMP3, STX6, SLC30A8) were affected. CONCLUSIONS: Using our newly developed experimental approach for efficient clock disruption in human pancreatic islet cells, we show for the first time that a functional ß-cell clock is required for proper basal and stimulated insulin secretion. Moreover, clock disruption has a profound impact on the human islet transcriptome, in particular, on the genes involved in insulin secretion.


Asunto(s)
Proteínas CLOCK/metabolismo , Relojes Circadianos , Hiperglucemia/metabolismo , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Proteínas CLOCK/antagonistas & inhibidores , Proteínas CLOCK/genética , Proteínas de Transporte de Catión/antagonistas & inhibidores , Proteínas de Transporte de Catión/química , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Células Cultivadas , Relojes Circadianos/efectos de los fármacos , Colforsina/farmacología , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/antagonistas & inhibidores , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/química , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica/efectos de los fármacos , Genes Reporteros/efectos de los fármacos , Humanos , Secreción de Insulina , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/efectos de los fármacos , Canales de Potasio de Rectificación Interna/antagonistas & inhibidores , Canales de Potasio de Rectificación Interna/química , Canales de Potasio de Rectificación Interna/genética , Canales de Potasio de Rectificación Interna/metabolismo , Proteínas Qa-SNARE/antagonistas & inhibidores , Proteínas Qa-SNARE/química , Proteínas Qa-SNARE/genética , Proteínas Qa-SNARE/metabolismo , Interferencia de ARN , ARN Interferente Pequeño , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , ATPasa Intercambiadora de Sodio-Potasio/química , ATPasa Intercambiadora de Sodio-Potasio/genética , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Proteína 3 de Membrana Asociada a Vesículas/antagonistas & inhibidores , Proteína 3 de Membrana Asociada a Vesículas/química , Proteína 3 de Membrana Asociada a Vesículas/genética , Proteína 3 de Membrana Asociada a Vesículas/metabolismo , Transportador 8 de Zinc
5.
Br J Surg ; 102(10): 1250-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26098966

RESUMEN

BACKGROUND: To date, studies assessing the risk of post-transplant hepatocellular carcinoma (HCC) recurrence have focused on tumour characteristics. This study investigated the impact of donor characteristics and graft quality on post-transplant HCC recurrence. METHODS: Using the Scientific Registry of Transplant Recipients patients with HCC who received a liver transplant between 2004 and 2011 were included, and post-transplant HCC recurrence was assessed. A multivariable competing risk regression model was fitted, adjusting for confounders such as recipient sex, age, tumour volume, α-fetoprotein, time on the waiting list and transplant centre. RESULTS: A total of 9724 liver transplant recipients were included. Patients receiving a graft procured from a donor older than 60 years (adjusted hazard ratio (HR) 1.38, 95 per cent c.i. 1.10 to 1.73; P = 0.006), a donor with a history of diabetes (adjusted HR 1.43, 1.11 to 1.83; P = 0.006) and a donor with a body mass index of 35 kg/m(2) or more (adjusted HR 1.36, 1.04 to 1.77; P = 0.023) had an increased rate of post-transplant HCC recurrence. In 3007 patients with documented steatosis, severe graft steatosis (more than 60 per cent) was also linked to an increased risk of recurrence (adjusted HR 1.65, 1.03 to 2.64; P = 0.037). Recipients of organs from donation after cardiac death donors with prolonged warm ischaemia had higher recurrence rates (adjusted HR 4.26, 1.20 to 15.1; P = 0.025). CONCLUSION: Donor-related factors such as donor age, body mass index, diabetes and steatosis are associated with an increased rate of HCC recurrence after liver transplantation.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Neoplasias Hepáticas/cirugía , Trasplante de Hígado , Donantes de Tejidos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Periodo Posoperatorio , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia/tendencias , Suiza/epidemiología , Factores de Tiempo , Listas de Espera
6.
Am J Transplant ; 14(11): 2595-606, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25278159

RESUMEN

The Collaborative Islet Transplant Registry (CITR) collects data on clinical islet isolations and transplants. This retrospective report analyzed 1017 islet isolation procedures performed for 537 recipients of allogeneic clinical islet transplantation in 1999-2010. This study describes changes in donor and islet isolation variables by era and factors associated with quantity and quality of final islet products. Donor body weight and BMI increased significantly over the period (p<0.001). Islet yield measures have improved with time including islet equivalent (IEQ)/particle ratio and IEQs infused. The average dose of islets infused significantly increased in the era of 2007-2010 when compared to 1999-2002 (445.4±156.8 vs. 421.3±155.4×0(3) IEQ; p<0.05). Islet purity and total number of ß cells significantly improved over the study period (p<0.01 and <0.05, respectively). Otherwise, the quality of clinical islets has remained consistently very high through this period, and differs substantially from nonclinical islets. In multivariate analysis of all recipient, donor and islet factors, and medical management factors, the only islet product characteristic that correlated with clinical outcomes was total IEQs infused. This analysis shows improvements in both quantity and some quality criteria of clinical islets produced over 1999-2010, and these parallel improvements in clinical outcomes over the same period.


Asunto(s)
Supervivencia de Injerto , Trasplante de Islotes Pancreáticos , Sistema de Registros , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
7.
Am J Transplant ; 13(4): 1093-1097, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23398948

RESUMEN

Long-term insulin independence after islets of Langerhans transplantation is rarely achieved. The aims of this study were to identify the histological and immunological features of islets transplanted in a type 1 diabetic patient who died of a cerebral hemorrhage after >13 years insulin independence. Islets were pooled from two donors with respectively one and five HLA mismatches. Insulin-positive islets were found throughout the right and left liver, and absent in the pancreas. Two- and three-dimensional analysis showed that islets lost their initial rounded and compact morphology, had a mean diameter of 136 µm and were constituted of an unfolded epithelial band of 39.1 µm. Leukocyte phenotyping showed no evidence of a tolerogenic environment in the islet-containing portal spaces. Finally, HLA typing of microdissected islets showed HLA from the best matched donor in all 23 microdissection samples, compared to 1/23 for the least matched donor. This case report demonstrates that allogeneic islets can survive over 13 years while maintaining insulin independence. Allogeneic islets had unique morphologic features and implanted in the liver regardless of their size. Finally, our results suggest that, in this case, rejection had been prevalent over autoimmunity, although this hypothesis warrants further investigation.


Asunto(s)
Diabetes Mellitus Tipo 1/terapia , Insulina/uso terapéutico , Trasplante de Islotes Pancreáticos/métodos , Adulto , Autoinmunidad , Femenino , Antígenos HLA/química , Cadenas HLA-DRB1/genética , Humanos , Sistema Inmunológico , Células Secretoras de Insulina/citología , Trasplante de Riñón/métodos , Leucocitos/citología , Hígado/patología , Microscopía Fluorescente , Páncreas/patología , Fenotipo , Reacción en Cadena de la Polimerasa , Resultado del Tratamiento
8.
Am J Transplant ; 12(2): 492-5, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22151900

RESUMEN

We report herein the patterns of type 1 diabetes recurrence in a simultaneous pancreas-kidney transplant (SPK) recipient, in the absence of rejection. A 38-year-old female underwent SPK for end-stage nephropathy secondary to type 1 diabetes. Fasting blood glucose, HbA1c, fructosamine, C-peptide and autoantibodies (GAD-65, IA-2) were monitored throughout follow-up. At 3.5 years post-SPK, HbA1c and fructosamine increased sharply, indicating loss of perfect metabolic control, despite C-peptide levels in the normal-high range. Exogenous insulin was restarted 4 months later. C-peptide levels abruptly fell and became undetectable at 5.5 years. Autoantibody levels, which were undetectable at the time of SPK, never converted to positivity. Pancreas retranspantation was performed at 6 years. The failed pancreas graft had a normal macroscopic appearance. On histology, there were no signs of cellular or humoral rejection in the kidney or pancreas. A selective peri-islet lymphocytic infiltrate was observed, together with near-total destruction of ß cells. At 2.5 years post retransplantation, pancreatic graft function is perfect. This observation indicates unequivocally that pancreas graft can be lost to recurrence of type 1 diabetes in the absence of rejection. GAD-65 and IA-2 autoantibodies are not reliable markers of autoimmunity recurrence.


Asunto(s)
Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/complicaciones , Glutamato Descarboxilasa/inmunología , Fallo Renal Crónico/cirugía , Trasplante de Riñón/inmunología , Trasplante de Páncreas/inmunología , Adulto , Autoanticuerpos/sangre , Autoinmunidad , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/complicaciones , Nefropatías Diabéticas/inmunología , Nefropatías Diabéticas/cirugía , Femenino , Estudios de Seguimiento , Glutamato Descarboxilasa/sangre , Humanos , Fallo Renal Crónico/etiología , Fallo Renal Crónico/inmunología , Recurrencia , Reoperación
10.
Psychol Med ; 42(3): 647-56, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21798110

RESUMEN

BACKGROUND: There are no tested methods for conducting epidemiological studies of autism spectrum disorders (ASDs) in adult general population samples. We tested the validity of the Autism Diagnostic Observation Schedule module-4 (ADOS-4) and the 20-item Autism-Spectrum Quotient (AQ-20). METHOD: Randomly sampled adults aged ≥16 years were interviewed throughout England in a general population multi-phase survey. The AQ-20 was self-completed by 7353 adults in phase 1. A random subset completed phase 2, ADOS-4 assessments (n=618); the probability of selection increased with AQ-20 score. In phase 3, informant-based Diagnostic Interview Schedule for Social and Communication Disorders (DISCO) and Autism Diagnostic Interview-Revised (ADI-R) developmental assessments were completed (n=56). Phase 1 and 2 data were presented as vignettes to six experienced clinicians (working in pairs). The probability of respondents having an ASD was compared across the three survey phases. RESULTS: There was moderate agreement between clinical consensus diagnoses and ADOS-4. A range of ADOS-4 caseness thresholds was identified by clinicians: 5+ to 13+ with greatest area under the curve (AUC) at 5+ (0.88). Modelling of the presence of ASD using 56 DISCO assessments suggested an ADOS-4 threshold in the range of 10+ to 13+ with the highest AUC at ADOS 10+ to 11+ (0.93-0.94). At ADOS 10+, the sensitivity was 1 [95% confidence interval (CI) 0.59-1.0] and the specificity 0.86 (95% CI 0.72-0.94). The AQ-20 was only a weak predictor of ADOS-4 cases. CONCLUSIONS: Clinically recommended ADOS-4 thresholds are also recommended for community cases: 7+ for subthreshold and 10+ for definite cases. Further work on adult population screening methods is needed.


Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/epidemiología , Encuestas Epidemiológicas/métodos , Encuestas y Cuestionarios/normas , Adolescente , Adulto , Anciano , Calibración , Niño , Trastornos Generalizados del Desarrollo Infantil/diagnóstico , Preescolar , Consenso , Inglaterra/epidemiología , Femenino , Humanos , Entrevista Psicológica , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
11.
J Hosp Infect ; 128: 47-53, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35840001

RESUMEN

BACKGROUND: Among hospital-acquired infections, surgical site infections (SSIs) are frequent. SSI in the early post-transplant course poses a relevant threat to transplant recipients. AIM: To determine incidence, risk factors for SSI and its association with post-transplant outcomes and pancreas transplant (P-Tx) recipients. METHODS: Adult simultaneous kidney-pancreas transplantation (SPK-T) and P-Tx recipients with a follow-up of at least 90 days were identified in the Swiss Transplant Cohort Study (STCS) dataset. Except for the categorization of SSIs according to Centers for Disease Control and Prevention (CDC) criteria, all other data were prospectively collected. Risk factors for SSI were investigated with logistic regression. A Weibull accelerated failure-time model was applied to address the impact of SSI on length of stay, correcting for transplant-related complications and delayed graft function. FINDINGS: Of 130 transplant recipients, 108 SPK-Tx and 22 P-Tx, 18 (14%) individuals developed SSI within the first 90 days after transplantation. Deep incisional (seven, 38.9%) and organ/space infections (eight, 44.4%) predominated. In the majority of SSIs (11, 61.1%; two SSIs with simultaneous identification of fungal pathogens) bacteria were detected with Enterococcus spp. being most frequent. The median duration of hospitalization after transplantation was significantly longer in recipients with SSI (median: 26 days; interquartile range (IQR): 19-44) than in patients without SSI (median: 17 days; IQR: 12-25; P = 0.002). In multivariate analysis, SSI was significantly associated with increased length of stay and prolonged the duration of hospitalization by 36% (95% confidence interval: 4-79). CONCLUSION: SSI after SPK-Tx and P-Tx occurred at a frequency of 14%. Among pathogens, Enterococcus spp. predominated. SSI was independently associated with a longer hospitalization after transplantation.


Asunto(s)
Trasplante de Riñón , Trasplante de Páncreas , Adulto , Estudios de Cohortes , Humanos , Riñón , Trasplante de Riñón/efectos adversos , Páncreas , Trasplante de Páncreas/efectos adversos , Factores de Riesgo , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/etiología , Suiza/epidemiología
12.
Diabetologia ; 54(11): 2856-66, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21847584

RESUMEN

AIMS/HYPOTHESIS: Pancreatic beta cell hyperactivity is known to occur in obesity, particularly in insulin-resistant states. Our aim was to investigate whether changes in neuronal nitric oxide synthase (nNOS) function affect beta cell compensation in two relevant models: the Zucker fa/fa rats and pancreatic islets from obese humans. METHODS: Glucose-induced insulin response was evaluated in the isolated perfused rat pancreas and in human pancreatic islets from obese individuals. Expression of nNOS (also known as NOS1) and subcellular localisation of nNOS were studied by quantitative RT-PCR, immunoblotting, immunofluorescence and electron microscopy. RESULTS: Pancreatic beta cells from Zucker fa/fa rats and obese individuals were found to be hyper-responsive to glucose. Pharmacological blockade of nNOS was unable to modify beta cell response to glucose in fa/fa rats and in islets from obese individuals, suggesting an abnormal control of insulin secretion by the enzyme. In both cases, nNOS activity in islet cell extracts remained unchanged, despite a drastic increase in nNOS protein and an enhancement in the dimer/monomer ratio, pointing to the presence of high amounts of catalytically inactive enzyme. This relative decrease in activity could be mainly related to increases in islet asymmetric dimethyl-arginine content, an endogenous inhibitor of nNOS activity. In addition, mitochondrial nNOS level was decreased, which contrasts with a strongly increased association with insulin granules. CONCLUSIONS/INTERPRETATION: Increased nNOS production and dimerisation, together with a relative decrease in catalytic activity and relocalisation, are involved in beta cell hyperactivity in insulin-resistant rats but also in human islets isolated from obese individuals.


Asunto(s)
Dimerización , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Obesidad/metabolismo , Animales , Células Cultivadas , Femenino , Regulación Enzimológica de la Expresión Génica , Humanos , Resistencia a la Insulina , Secreción de Insulina , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/ultraestructura , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Islotes Pancreáticos/ultraestructura , Masculino , Persona de Mediana Edad , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/ultraestructura , Óxido Nítrico Sintasa de Tipo I/antagonistas & inhibidores , Óxido Nítrico Sintasa de Tipo I/genética , Transporte de Proteínas , ARN Mensajero/metabolismo , Ratas , Ratas Mutantes , Ratas Zucker , Técnicas de Cultivo de Tejidos
13.
Am J Transplant ; 11(6): 1158-68, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21564535

RESUMEN

The Automatic Quantitative Ultrashort Echo Time imaging (AQUTE) protocol for serial MRI allows quantitative in vivo monitoring of iron labeled pancreatic islets of Langerhans transplanted into the liver, quantifying graft implantation and persistence in a rodent model. Rats (n = 14), transplanted with iron oxide loaded cells (0-4000 islet equivalents, IEQ), were imaged using a 3D radial ultrashort echo time difference technique (dUTE) on a Siemens MAGNETOM 3T clinical scanner up to 5 months postsurgery. In vivo 3D dUTE images gave positive contrast from labeled cells, suppressing liver signal and small vessels, allowing automatic quantification. Position of labeled islet clusters was consistent over time and quantification of hyperintense pixels correlated with the number of injected IEQs (R² = 0.898, p < 0.0001), and showed persistence over time (5 months posttransplantation). Automatic quantification was superior to standard imaging and manual counting methods, due to the uniform suppressed background and high contrast, resulting in significant timesavings, reproducibility and ease of quantification. Three-dimensional coverage of the whole liver in the absence of cardiac/respiratory artifact provided further improvement over conventional imaging. This imaging protocol reliably quantifies transplanted islet mass and has high translational potential to clinical studies of transplanted pancreatic islets.


Asunto(s)
Medios de Contraste , Trasplante de Islotes Pancreáticos , Islotes Pancreáticos/patología , Imagen por Resonancia Magnética/métodos , Animales , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados
14.
Vaccine ; 39(26): 3459-3466, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-34023135

RESUMEN

BACKGROUND: Solid organ transplantation (SOT) candidates and recipients are highly vulnerable to invasive pneumococcal diseases (IPD). Data on which to base optimal immunization recommendations for this population is scant. The national distribution of IPD serotypes led the Swiss Health Authorities to recommend in 2014 one dose of pneumococcal-13-valent-conjugate-vaccine (PCV13), without any subsequent dose of the 23-valent-polysaccharide-pneumococcal-vaccine (PPV23). METHODS: This is a retrospective analysis of pneumococcal immunity using a multiplex binding assay, to assess seroprotection rates against a selection of seven PCV13- and seven PPV23-serotypes in SOT-candidates and recipients evaluated and/or transplanted in 2014/2015 in the University Hospitals of Geneva. Seroprotection was defined as serotype-specific antibody concentration greater than 0.5 mg/l and overall seroprotection when this was achieved for ≥ 6/7 serotypes. RESULTS: Pre-vaccination and at time of transplant sera were available for 35/43 (81%), and 43/43 (100%) SOT-candidates respectively. At listing, 17/35 (49%) SOT-candidates were seroprotected against PCV13 and 21/35 (60%) against PPV23 serotypes. Following one systematic dose of PCV13 at listing, 35/43 (81%) SOT-recipients were seroprotected at day of transplant against PCV13-serotypes and 34/43 (79%) against PPV23 serotypes, compared to 21/41 (51%) and 28/41 (68%) respectively in the controls transplanted in 2013, before the systematic PCV13-vaccination. CONCLUSIONS: The systematic vaccination with PCV13 of all SOT candidates without additional PPV23 is a good strategy as it confers seroprotection against a wide range of pneumococcal serotypes. Indeed, one of five PCV13-vaccinated SOT-candidates was nevertheless not seroprotected at time of transplant, reflecting their partial immune competence, and indicating the need for additional dose of pneumococcal vaccines before transplant.


Asunto(s)
Trasplante de Órganos , Infecciones Neumocócicas , Humanos , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas , Estudios Retrospectivos , Streptococcus pneumoniae , Vacunas Conjugadas
15.
Am J Transplant ; 10(7): 1707-12, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20642693

RESUMEN

Patients with end-stage cystic fibrosis (CF) and severe CF-related diabetes (CFRD) may benefit from combined lung-pancreatic islet transplantation. In the present study, we report the long-term follow-up of four end-stage CF patients treated with combined bilateral lung and pancreatic islet transplantation from the same donor. All patients were C-peptide negative (<0.5 microg/L) and inadequately controlled despite intensive insulin treatment. One patient was transplanted with 4 019 +/- 490 islet equivalent/kg injected into the transverse colic vein using a surgical approach. In the remaining three patients, islets were cultured for 3-6 days and transplanted by percutaneous transhepatic catheterization of the portal vein. In all patients, islet allograft recovery was recognized by elevation in the plasma level of C-peptide (>0.5 microg/L). At 6 months after transplantation, one patient showed multiple episodes of acute lung transplant rejection and a progressive decline in pancreatic islet cell function. Three out of four patients experienced an improved control of glucose levels with a HbA1c of 5.2%, 7% and 6% respectively at 1.5, 2 and 15 years follow-up. Compared with the pretransplant period, there was a 50% reduction in mean daily insulin needs. Pulmonary function remained satisfactory in all patients. In conclusion, our cases series shows that combined bilateral lung and pancreatic islet transplantation may be a viable therapeutic option for patients with end-stage CF and CFRD.


Asunto(s)
Fibrosis Quística/cirugía , Trasplante de Islotes Pancreáticos/métodos , Trasplante de Pulmón/métodos , Adolescente , Adulto , Edad de Inicio , Péptido C/sangre , Terapia Combinada , Fibrosis Quística/complicaciones , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Complicaciones de la Diabetes/cirugía , Volumen Espiratorio Forzado , Humanos , Masculino , Mutación , Eliminación de Secuencia , Trasplante Homólogo , Resultado del Tratamiento , Capacidad Vital , Adulto Joven
16.
Rev Med Suisse ; 6(254): 1302-5, 2010 Jun 23.
Artículo en Francés | MEDLINE | ID: mdl-20672687

RESUMEN

The trend is to definitely shorten hospital stays. It follows in the footsteps of a broader range of surgeries that can be managed in an ambulatory care setting. The expected benefits are: a reduction in costs, a shorter preoperative delay, a shorter absence for the work place and a lessened risk of hospital-borne infections. A multidisciplinary approach is essential for the success of such a program. Surgeons, anaesthetists and nursing staff must be prepared to modify and adapt their skills. The criterion of success for such an endeavour is a low level of readmissions and hospitalisations. If day surgery tends to keep the patient away for the hospital settings, it certainly places him in the centre of his medical management.


Asunto(s)
Procedimientos Quirúrgicos Ambulatorios/estadística & datos numéricos , Vías Clínicas , Humanos
17.
Am J Transplant ; 9(2): 419-23, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19120085

RESUMEN

Results of islet of Langerhans transplantation have markedly improved in recent years, but most patients still lose insulin independence in the long-term. We report herein the longest (over 11 years) case of insulin independence after allogeneic islet transplantation. The subject had a 27-year history of type 1 diabetes and received a single islet-after-kidney graft of 8800 islet equivalents (IEQ)/kg, pooled from 2 donors. Insulin was discontinued by 3 months posttransplant and the patient has remained off insulin ever since. Yearly follow-up studies have revealed normal metabolic control, including normal oral glucose tolerance test (OGTT). Reasons for success may involve choice of immunosuppression, low metabolic demand and low immune responsiveness as suggested by an excellent HLA matching and a high count of circulating regulatory T cells. This observation is so far an exceptional case, but clearly demonstrates the validity of the concept that long-term insulin independence after allogeneic islet transplantation is an achievable target.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Hipoglucemiantes/sangre , Insulina/sangre , Trasplante de Islotes Pancreáticos , Adulto , Glucemia/metabolismo , Femenino , Supervivencia de Injerto , Humanos , Terapia de Inmunosupresión , Periodo Posoperatorio , Factores de Tiempo , Trasplante Homólogo , Resultado del Tratamiento
18.
Am J Transplant ; 9(8): 1961-6, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19522877

RESUMEN

We describe the decline in islet function, in relation to HLA sensitization, in an islet transplant recipient and the recovery of this function after treatment with anti-CD20 monoclonal antibody and IV immunoglobulins. A 51-year-old woman with type 1 diabetes received one intraportal islet infusion. Following this transplantation, she became insulin independent. A search for HLA antibodies by using an ELISA technique remained consistently negative for HLA class I and II. It was only 2 years after the islet transplantation that this search became positive against class II antigens, reaching a peak of reactivity concomitantly with the appearance of a deterioration of glucose control requiring low-dose insulin therapy. Luminex screening and single-antigen assays then revealed the presence of both nondonor-specific and donor-specific antibodies against HLA class II molecules. This immunization, already present in the pretransplant serum, had increased during the 6 months preceding the clinical deterioration. Since these data nevertheless pointed to antibody-mediated rejection of the islet allograft, treatment with anti-CD20 monoclonal antibody and IV immunoglobulins was initiated. One month later, the search by ELISA for antibodies against HLA class II antigens became negative, the Luminex tests normalizing more gradually. As the result of an improvement in glucose control, the patient was again insulin-free.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/inmunología , Inmunidad Humoral/inmunología , Inmunoglobulinas Intravenosas/uso terapéutico , Factores Inmunológicos/uso terapéutico , Trasplante de Islotes Pancreáticos/inmunología , Anticuerpos Monoclonales de Origen Murino , Femenino , Humanos , Persona de Mediana Edad , Rituximab , Resultado del Tratamiento
19.
Diabet Med ; 26(6): 617-21, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19538237

RESUMEN

BACKGROUND: Rigorous assessment of health-related quality of life (HRQL) is mandatory to establish the benefits of islet transplantation. METHODS: The 36-Item Short Form Health Survey (SF-36) and the Diabetes Quality of Life (DQOL) scales were completed by patients included in an Islet Transplantation Alone (ITA) trial (n = 10) and an Islet After Kidney (IAK) trial (n = 10). RESULTS: The two populations differed by HRQL scores at baseline, with poorer scores in ITA patients. SF-36 scores for physical limitations, bodily pain, general health perception, social functioning, and health transition improved significantly in ITA patients 6 and 12 months post transplantation. The DQOL global score was significantly improved at 6 months and remained so at 12 months, because of a significant improvement in the dimensions of satisfaction and impact of diabetes. No improvement was observed in the IAK patients. CONCLUSION: HRQL assessment may help in the selection of candidates with brittle diabetes for islet transplantation.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos , Calidad de Vida , Ensayos Clínicos como Asunto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
20.
Rev Med Suisse ; 5(209): 1425-30, 2009 Jun 24.
Artículo en Francés | MEDLINE | ID: mdl-19715020

RESUMEN

Acute pancreatitis is a potentially lethal inflammatory disease with an increased incidence and a decreased mortality rate. The main etiologies are biliary stones and alcohol abuse. The therapeutic approach consists of the elimination of the cause, the hemodynamic and respiratory supports and the treatment of the complications. Moreover, severe acute pancreatitis requires a collaboration between surgeons, radiologists, gastroenterologists and intensive care physicians. The administration of prophylactic antibiotics and the early oral nutritional support are still controversial. In summary, the anticipation in diagnosis, etiology, classification of the severity and early reanimation are needed for an optimal treatment of this complex disease.


Asunto(s)
Pancreatitis/diagnóstico , Pancreatitis/terapia , Antibacterianos/uso terapéutico , Colangiopancreatografia Retrógrada Endoscópica , Diagnóstico por Imagen , Humanos , Pancreatitis/complicaciones , Índice de Severidad de la Enfermedad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA