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1.
Artículo en Inglés | MEDLINE | ID: mdl-38764195

RESUMEN

OBJECTIVE: to describe the normal features of the caudo-thalamic groove at antenatal brain ultrasound in a group of structurally normal fetuses at third trimester and to report a small series of cases with abnormal appearance of the caudothalamic groove at antenatal brain ultrasound. METHODS: This was an observational study conducted at two referral Fetal Medicine units. A non-consecutive cohort of pregnant women with a singleton non anomalous pregnancy were prospectively recruited and underwent 3D ultrasound of the fetal brain at 28-32 weeks. At offline analysis the ultrasound volumes were adjusted in the multiplanar mode according to a standardized methodology, until the caudothalamic groove was visible on the parasagittal plane. To evaluate the inter-observer agreement, two operators were independently asked to indicate if the caudothalamic groove was visible unilaterally or bilaterally on each volume. The digital archives of the two Centres were also retrospectively searched to retrieve cases with abnormal findings at the level of the caudothalamic groove at antenatal brain ultrasound which were postnatally confirmed. RESULTS: 180 non-consecutive cases fulfilling the inclusion criteria were prospectively included. At offline analysis of the 3D US volumes the caudo-thalamic groove was identified on the parasagittal plane by both operators at least unilaterally in 176 cases (97.8%) and bilaterally in 174 cases (96.6%). The K-coefficient for the agreement between the two independent operators in recognizing the caudo-thalamic groove was 0.89 and 0.83 on one and both hemispheres respectively. At the retrospective search of our archives 5 cases with abnormal appearance of the groove at antenatal brain ultrasound (2 haemorrhage and 3 cyst) were found. CONCLUSION: Our study has demonstrated that the caudo-thalamic groove is consistently seen among normal fetuses at third trimester submitted to multiplanar neurosonography and that abnormal findings at this level may be antenatally detected. This article is protected by copyright. All rights reserved.

2.
Pharmacol Res ; 141: 319-330, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30625359

RESUMEN

Eph/ephrin interactions and their bidirectional signaling are integral part of the complex communication system between ß-cells, essential for glucose homeostasis. Indeed, Eph/ephrin system was shown to be directly involved in the glucose-stimulated insulin secretion (GSIS) process occurring in the pancreatic islets. Here we tested the Eph antagonist UniPR500 as GSIS enhancer. UniPR500 was validated as EphA5-ephrin-A5 inhibitor in vitro and its efficacy as GSIS enhancer was assessed on EndoC-ßH1 cells. The selectivity of UniPR500 was evaluated by testing this compound on a panel of well-known molecular targets responsible for the regulation of glucose homeostasis. Plasmatic levels of UniPR500 were measured by HPLC/MS approach after oral administration. Finally, UniPR500 was tested as hypoglycemic agent in healthy mice, in a non-genetic mouse model of insulin resistance (IR) and in a non-genetic mouse model of type 1 diabetes (T1D). The compound is an orally bioavailable and selective Eph antagonist, able to increase GSIS from EndoC-ßH1 cells. When tested in vivo UniPR500 showed to improve glucose tolerance in healthy and IR mice. As expected by a GSIS enhancer acting on healthy ß-cells, UniPR500 was ineffective when tested on a non-genetic mouse model of type 1 diabetes, where pancreatic function was severely compromised. In conclusion our findings suggest that Eph targeting is a new and valuable pharmacological strategy in the search of new hypoglycemic agents.


Asunto(s)
Efrinas/metabolismo , Glucosa/metabolismo , Hipoglucemiantes/farmacología , Resistencia a la Insulina , Secreción de Insulina/efectos de los fármacos , Mapas de Interacción de Proteínas/efectos de los fármacos , Animales , Línea Celular , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/metabolismo , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Masculino , Ratones Endogámicos C57BL
3.
Diabet Med ; 35(7): 954-963, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29577424

RESUMEN

AIMS: Glutamate decarboxylase (GAD) antibodies are the most widely used predictive marker for Type 1 diabetes, but many individuals currently found to be GAD antibody-positive are unlikely to develop diabetes. We have shown previously that radioimmunoassays using N-terminally truncated 35 S-GAD65 (96-585) offer better disease specificity with similar sensitivity to full-length 35 S-GAD65 (1-585). To determine whether assay performance could be improved further, we evaluated a more radically truncated 35 S-GAD65 (143-585) radiolabel. METHODS: Samples from people with recent-onset Type 1 diabetes (n = 157) and their first-degree relatives (n = 745) from the Bart's-Oxford family study of childhood diabetes were measured for GAD antibodies using 35 S-labelled GAD65 (143-585). These were screened previously using a local radioimmunoassay with 35 S-GAD65 (1-585). A subset was also tested by enzyme-linked immunosorbent assay (ELISA), which performs well in international workshops, but requires 10 times more serum. Results were compared with GAD antibody measurements using 35 S-GAD65 (1-585) and 35 S-GAD65 (96-585). RESULTS: Sensitivity of GAD antibody measurement was maintained using 35 S-GAD65 (143-585) compared with 35 S-GAD65 (1-585) and 35 S-GAD65 (96-585). Specificity for Type 1 diabetes was improved compared with 35 S-GAD65 (1-585), but was similar to 35 S-GAD65 (96-585). Relatives found to be GAD antibody-positive using these truncated labels were at increased risk of diabetes progression within 15 years, compared with those positive for GAD(1-585) antibody only, and at similar risk to those found GAD antibody-positive by ELISA. CONCLUSIONS: The first 142 amino acids of GAD65 do not contribute to epitopes recognized by Type 1 diabetes-associated GAD antibodies. Low-volume radioimmunoassays using N-terminally truncated 35 S-GAD65 are more specific than those using full-length GAD65 and offer practical alternatives to the GAD antibody ELISA for identifying children at increased risk of Type 1 diabetes.


Asunto(s)
Autoanticuerpos/inmunología , Diabetes Mellitus Tipo 1/inmunología , Glutamato Descarboxilasa/inmunología , Fragmentos de Péptidos/inmunología , Adolescente , Adulto , Anciano , Niño , Preescolar , Diabetes Mellitus Tipo 1/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Epítopos/inmunología , Familia , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Radioinmunoensayo , Sensibilidad y Especificidad , Adulto Joven
4.
Am J Transplant ; 17(10): 2720-2727, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28510280

RESUMEN

Iatrogenic pancreatic cancer metastasis after islet infusion is a potential risk of islet autotransplantation performed after pancreatectomy. To model this risk, islets and/or pancreatic exocrine clusters obtained from a genetically engineered mouse model for pancreatic ductal adenocarcinoma (the LSL-KrasG12D/+ ;LSL-Trp53R172H/+ ;Pdx-1-Cre, termed KPC mouse) were transplanted via the portal vein in syngeneic wild type (WT) severely diabetic recipients in the following treatment groups: group A (n = 11) received KPC exocrine clusters in volume equal to 250 islet equivalents (IEQs); group B (n = 12) received 250 WT IEQs mixed with KPC exocrine clusters (1:1 volume ratio); group C (n = 5) received 250 KPC IEQs, and group D (n = 7) received 250 WT IEQs. The incidence of hepatic metastasis was assessed by magnetic resonance imaging and histology over the 13 months of follow-up. Overall survival was not different in the four groups. No mice developed liver metastases during the follow-up. Two mice developed spontaneous tumors: a liver hepatocellular tumor in group A and a malignant lymphoma in group D. Islets and/or exocrine clusters obtained by KPC mouse, a model that develops pancreatic cancer with 100% penetrance, do not retain the same risk of tumor development when transplanted via the portal vein in a syngeneic diabetic recipient.


Asunto(s)
Carcinoma Ductal Pancreático/etiología , Modelos Animales de Enfermedad , Enfermedad Iatrogénica , Trasplante de Islotes Pancreáticos/efectos adversos , Neoplasias Pancreáticas/etiología , Animales , Carcinoma Ductal Pancreático/patología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Neoplasias Pancreáticas/patología
5.
Nutr Metab Cardiovasc Dis ; 27(7): 583-600, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28545927

RESUMEN

BACKGROUND: The advancement of knowledge in the field of regenerative medicine is increasing the therapeutic expectations of patients and clinicians on cell therapy approaches. Within these, stem cell therapies are often evoked as a possible therapeutic option for diabetes, already ongoing or possible in the near future. AIM: The purpose of this document is to make a point of the situation on existing knowledge and therapies with stem cells to treat patients with diabetes by focusing on some of the aspects that most frequently raise curiosity and discussion in clinical practice and in the interaction with the patient. In fact, at present there are no clinically approved treatments based on the use of stem cells for the treatment of diabetes, but several therapeutic approaches have already been evaluated or are being evaluated in clinical trials. DATA SYNTHESIS: It is possible to identify three large potential application fields: 1) the reconstruction of the ß cell mass; 2) the immunomodulation in type 1 diabetes (T1D); 3) the treatment of complications. In this study we will limit the discussion to approaches that have the potential for clinical translation, deliberately omitting aspects of basic biology and preclinical data. Also, we intentionally omit the treatment of the complications that will be the subject of a future document. Finally, an overview of the Italian situation regarding the storage of cord blood cells for the therapy of diabetes will be given.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Células Secretoras de Insulina/trasplante , Regeneración , Trasplante de Células Madre/métodos , Animales , Diferenciación Celular , Linaje de la Célula , Proliferación Celular , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/diagnóstico , Humanos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patología , Fenotipo , Trasplante de Células Madre/efectos adversos , Resultado del Tratamiento
6.
Am J Transplant ; 16(6): 1812-26, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26695701

RESUMEN

Islet autotransplantation (IAT) is usually performed in patients undergoing pancreatic surgery for chronic pancreatitis. In the present series, IAT was offered also to patients undergoing pancreatic surgery for both nonmalignant and malignant diseases, having either completion pancreatectomy as treatment for severe pancreatic fistulas (n = 21) or extensive distal pancreatectomy for neoplasms of the pancreatic neck (n = 19) or pancreatoduodenectomy because of the high risk of pancreatic fistula (n = 32). Fifty-eight of 72 patients who were eligible to this broader spectrum of indication actually received IAT. There was no evidence of a higher-than-expected rate of major complications for pancreatectomy. Forty-five patients receiving IAT were still alive at the time of the last scheduled follow-up (1375 ± 365 days). Eighteen (95%) of 19 and 11 (28%) of 39 patients reached insulin independence after partial or total pancreatectomy, respectively. The metabolic results were dependent on the transplanted islet mass. Thirty-one of 58 patients had malignant diseases of the pancreas or periampullary region, and only three patients developed ex novo liver metastases after IAT (median follow-up 914 ± 382 days). Our data demonstrate the feasibility, efficacy, and safety of IAT for a broader spectrum of clinical indications beyond chronic pancreatitis.


Asunto(s)
Supervivencia de Injerto , Trasplante de Islotes Pancreáticos , Pancreatectomía , Enfermedades Pancreáticas/cirugía , Pancreatitis Crónica/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trasplante Autólogo , Resultado del Tratamiento
7.
Am J Transplant ; 14(1): 202-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24219129

RESUMEN

The aim of this study was to investigate liver microvascular adaptation following the intraportal infusion of pancreatic islets (pancreatic islet transplantation [islet-tx]) in diabetic patients using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). DCE-MRI was performed before and 7 days after islet-tx in six diabetic patients. Initial area under curve (AUC60) and volume transfer coefficient (Ktrans) were assessed as markers of liver perfusion. Clinical and metabolic monthly follow-up was performed in all patients, considering fasting C-peptide and ß-score as main indices of graft function. High variability in the response of liver microvasculature to islet infusion was observed: two patients showed a significant reduction in liver perfusion after transplantation (pt.2: AUC60 = -23.4%, Ktrans = -31.7%; pt.4: AUC60 = -23.7%, Ktrans = -27.9%); three patients did not show any significant variation of liver perfusion and one patient showed a significant increase (pt.3: AUC60 = +31%, Ktrans = +42.8%). Interestingly, a correlation between DCE-MRI parameters and indices of graft function was observed and, in particular, both patients with DCE-MRI evidence of posttransplantation liver perfusion reduction experienced premature graft failure. Our preliminary study demonstrated that DCE-MRI may identify different adaptive responses of liver microvasculature in patients submitted to islet-tx. These different responses could have an impact on islet engraftment, although reported findings need confirmation from larger studies.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos/métodos , Hígado/irrigación sanguínea , Adulto , Anciano , Femenino , Humanos , Hígado/fisiología , Imagen por Resonancia Magnética/métodos , Masculino , Microvasos/anatomía & histología , Persona de Mediana Edad
8.
Diabetologia ; 56(6): 1350-5, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23475368

RESUMEN

AIMS/HYPOTHESIS: Type 2 diabetes is characterised by impaired glucose-stimulated insulin secretion (GSIS) from pancreatic islets. Since erythropoietin-producing hepatoma (Eph)-ephrin bidirectional signalling fine-tunes GSIS from pancreatic beta cells, we investigated Eph receptor tyrosine kinases (RTK) as potential drug targets for selectively increasing GSIS. METHODS: Insulin secretion assays were carried out using mouse and human pancreatic islets as well as mouse insulinoma (MIN6) cells in the presence or absence of two Eph RTK inhibitors. Furthermore, the most potent inhibitor was injected into mice to evaluate its effects on glucose tolerance and plasma insulin levels. RESULTS: We showed that the Eph RTK inhibitors selectively increased GSIS from MIN6 cells as well as mouse and human islets. Our results also showed that the insulin secretory effects of these compounds required Eph-ephrin signalling. Finally, pharmacological inhibition of Eph receptor signalling improved glucose tolerance in mice. CONCLUSIONS/INTERPRETATION: We showed for the first time that Eph RTKs represent targets for small molecules to selectively increase GSIS and improve glucose tolerance.


Asunto(s)
Glucosa/metabolismo , Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Receptores de la Familia Eph/metabolismo , Animales , Benzamidas/farmacología , Línea Celular , Supervivencia Celular , Diabetes Mellitus Tipo 2/metabolismo , Eritropoyetina/metabolismo , Humanos , Mesilato de Imatinib , Insulina/sangre , Secreción de Insulina , Insulinoma/metabolismo , Espectroscopía de Resonancia Magnética , Ratones , Ratones Transgénicos , Fosforilación , Piperazinas/farmacología , Pirimidinas/farmacología , Receptor EphA5/metabolismo , Receptores de la Familia Eph/antagonistas & inhibidores
9.
Diabetologia ; 56(1): 31-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23073708

RESUMEN

AIMS/HYPOTHESIS: Exercise-induced hyperinsulinism (EIHI) is a hypoglycaemic disorder characterised by inappropriate insulin secretion following anaerobic exercise or pyruvate load. Activating promoter mutations in the MCT1 gene (also known as SCLA16A1), coding for monocarboxylate transporter 1 (MCT1), were shown to associate with EIHI. Recently, transgenic Mct1 expression in pancreatic beta cells was shown to introduce EIHI symptoms in mice. To date, MCT1 has not been demonstrated in insulin-producing cells from an EIHI patient. METHODS: In vivo insulin secretion was studied during an exercise test before and after the resection of an insulinoma. The presence of MCT1 was analysed using immunohistochemistry followed by laser scanning microscopy, western blot analysis and real-time RT-PCR of MCT1. The presence of MCT1 protein was analysed in four additional insulinoma patients. RESULTS: Clinical testing revealed massive insulin secretion induced by anaerobic exercise preoperatively, but not postoperatively. MCT1 protein was not detected in the patient's normal islets. In contrast, immunoreactivity was clearly observed in the insulinoma tissue. Western blot analysis and real-time RT-PCR showed a four- to fivefold increase in MCT1 in the insulinoma tissue of the EIHI patient compared with human pancreatic islets. MCT1 protein was detected in three of four additional insulinomas. CONCLUSIONS/INTERPRETATION: We show for the first time that an MCT1-expressing insulinoma was associated with EIHI and that MCT1 might be present in most insulinomas. Our data suggest that MCT1 expression in human insulin-producing cells can lead to EIHI and warrant further studies on the role of MCT1 in human insulinoma patients.


Asunto(s)
Hiperinsulinismo/etiología , Hipoglucemia/etiología , Células Secretoras de Insulina/metabolismo , Insulinoma/fisiopatología , Transportadores de Ácidos Monocarboxílicos/metabolismo , Actividad Motora , Proteínas de Neoplasias/metabolismo , Simportadores/metabolismo , Adolescente , Prueba de Esfuerzo , Femenino , Humanos , Hiperinsulinismo/fisiopatología , Hipoglucemia/prevención & control , Células Secretoras de Insulina/patología , Insulinoma/metabolismo , Insulinoma/patología , Insulinoma/cirugía , Masculino , Persona de Mediana Edad , Transportadores de Ácidos Monocarboxílicos/genética , Fases del Sueño , Trastornos del Sueño-Vigilia/etiología , Trastornos del Sueño-Vigilia/prevención & control , Simportadores/genética , Resultado del Tratamiento , Inconsciencia/etiología , Inconsciencia/prevención & control
10.
Diabetologia ; 55(9): 2479-88, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22684312

RESUMEN

AIMS/HYPOTHESIS: The purpose of this study was to investigate whether the gut mucosa is a reservoir for enterovirus persistence in patients with type 1 diabetes. METHODS: Small intestine biopsy samples from 25 individuals at different stages of type 1 diabetes, 21 control individuals and 27 individuals with coeliac disease were analysed for the presence of enterovirus RNA by using both radioactive in-situ hybridisation and real-time RT-PCR and for the presence of enterovirus proteins by immunostaining with antibodies against VP1 and VP4-2-3 capsid proteins and virus polymerase. Lymphocytic enteropathy and serum anti-VP1 antibodies were also evaluated at the time of biopsy. Moreover, high-throughput sequencing was performed to identify viral transcripts or genomes. RESULTS: Enterovirus was not detected by in-situ hybridisation or RT-PCR in any of the individuals tested. Immunohistology revealed a few stained cells in the intestinal epithelium in a low number of individuals, with no difference between diabetic and non-diabetic individuals. Levels of serum IgG against VP1 did not differ between control individuals and those with diabetes or coeliac disease and no evidence of diabetes-related lymphocytic enteropathy was detected. High-throughput sequencing did not reveal specific enterovirus sequences in the gut mucosa of individuals with type 1 diabetes. CONCLUSIONS/INTERPRETATION: Prolonged/persistent enterovirus infections in gut mucosa are not common in patients with type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Infecciones por Enterovirus/patología , Enterovirus/aislamiento & purificación , Mucosa Intestinal/patología , Adolescente , Adulto , Anciano , Niño , Preescolar , Diabetes Mellitus Tipo 1/patología , Diabetes Mellitus Tipo 1/virología , Femenino , Humanos , Inmunohistoquímica , Hibridación in Situ , Mucosa Intestinal/virología , Masculino , Persona de Mediana Edad , ARN Viral , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Replicación Viral , Adulto Joven
11.
Diabetologia ; 55(12): 3273-83, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22983635

RESUMEN

AIMS/HYPOTHESIS: Virally induced inflammatory responses, beta cell destruction and release of beta cell autoantigens may lead to autoimmune reactions culminating in type 1 diabetes. Therefore, viral capability to induce beta cell death and the nature of virus-induced immune responses are among key determinants of diabetogenic viruses. We hypothesised that enterovirus infection induces a specific gene expression pattern that results in islet destruction and that such a host response pattern is not shared among all enterovirus infections but varies between virus strains. METHODS: The changes in global gene expression and secreted cytokine profiles induced by lytic or benign enterovirus infections were studied in primary human pancreatic islet using DNA microarrays and viral strains either isolated at the clinical onset of type 1 diabetes or capable of causing a diabetes-like condition in mice. RESULTS: The expression of pro-inflammatory cytokine genes (IL-1-α, IL-1-ß and TNF-α) that also mediate cytokine-induced beta cell dysfunction correlated with the lytic potential of a virus. Temporally increasing gene expression levels of double-stranded RNA recognition receptors, antiviral molecules, cytokines and chemokines were detected for all studied virus strains. Lytic coxsackievirus B5 (CBV-5)-DS infection also downregulated genes involved in glycolysis and insulin secretion. CONCLUSIONS/INTERPRETATION: The results suggest a distinct, virus-strain-specific, gene expression pattern leading to pancreatic islet destruction and pro-inflammatory effects after enterovirus infection. However, neither viral replication nor cytotoxic cytokine production alone are sufficient to induce necrotic cell death. More likely the combined effect of these and possibly cellular energy depletion lie behind the enterovirus-induced necrosis of islets.


Asunto(s)
Efecto Citopatogénico Viral/inmunología , Diabetes Mellitus Tipo 1/patología , Enterovirus Humano B/inmunología , Infecciones por Enterovirus/patología , Animales , Células Cultivadas , Diabetes Mellitus Tipo 1/inmunología , Diabetes Mellitus Tipo 1/virología , Enterovirus Humano B/patogenicidad , Infecciones por Enterovirus/inmunología , Infecciones por Enterovirus/virología , Femenino , Regulación de la Expresión Génica , Humanos , Inmunidad Innata , Inmunohistoquímica , Inflamación , Interleucina-1alfa/inmunología , Interleucina-1beta/inmunología , Masculino , Ratones , Persona de Mediana Edad , Necrosis , Factor de Necrosis Tumoral alfa/inmunología
12.
Diabetologia ; 54(2): 433-9, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21046356

RESUMEN

AIMS/HYPOTHESIS: Type 1 diabetes is considered non-reversible at end-stage disease when there is no measurable insulin production. However, there are indications that insulin-producing beta cells could be present or return if autoimmunity could be controlled. We therefore sought to determine whether immunosuppression therapy can reinstate beta cell function in patients with long-term type 1 diabetes. METHODS: We examined pancreatic beta cell function in 22 patients with long-term type 1 diabetes (median disease duration 27 years), who had been receiving rapamycin monotherapy (0.1 mg/kg; target trough levels 8-10 ng/ml; 26-314 days) as pre-conditioning for islet transplantation. As control, beta cell function was measured in 14 patients (median disease duration 17 years) who were waiting for an islet transplant without rapamycin pre-conditioning. RESULTS: Fasting C-peptide increased from <0.03 nmol/l (0.0066 nmol/l, interquartile range [IQR] 0.0003-0.023) at baseline to 0.039 nmol/l (IQR 0.0066-0.096) at end of rapamycin monotherapy (p < 0.005). In 12 patients, fasting C-peptide increased to >0.076 nmol/l (C-peptide responders). Exogenous insulin requirement decreased from 0.64 U/kg daily (IQR 0.56-0.72) to 0.57 U/kg (IQR 0.45-0.70; p = 0.01), but this reduction was significant only in the 12C-peptide-responsive patients. Rapamycin monotherapy was also associated with a decrease in insulin antibody titre (median decrease 110 to 35.9 U/ml; p < 0.001) and fasting serum proinsulin (median decrease 0.51 to 0.28 pmol/l; p = 0.001). All variables remained unchanged in the 14 control patients. CONCLUSIONS/INTERPRETATION: Therapies to reinstate beta cell function may be applicable to patients with long-term C-peptide-negative type 1 diabetes. TRIAL REGISTRATION: ClinicalTrial.gov NCT01060605.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/fisiopatología , Inmunosupresores/uso terapéutico , Células Secretoras de Insulina/fisiología , Sirolimus/uso terapéutico , Adulto , Diabetes Mellitus Tipo 1/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proinsulina/sangre
13.
Diabetologia ; 52(3): 486-93, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19096824

RESUMEN

AIMS/HYPOTHESIS: While the mechanisms of specification and the reciprocal relationships of the four types of endocrine cell (alpha, beta, delta and pancreatic polypeptide cells) within the human endocrine pancreas are well described in adults and during fetal development, ghrelin-immunoreactive cells (epsilon cells) remain poorly understood. METHODS: We studied epsilon cells in 24 human fetal pancreases between 11 and 39 weeks of development and in 32 pancreases from adult organ donors. RESULTS: We observed single epsilon cells scattered in primitive exocrine tissue from gestational week 13 in developing pancreas. Later in the developmental process, epsilon cells started to aggregate into clusters. From gestational week 21, epsilon cells were observed located around developing islets, forming an almost continuous layer at the peripheral rim of the islets. They remain localised on the mantle of the islets, although at different amounts, in the adult pancreas. Co-production of ghrelin with insulin, glucagon or somatostatin was not detected during fetal development. Co-production with pancreatic polypeptide was evident sporadically. Epsilon cells co-produced NK2 homeobox 2 and ISL LIM homeobox 1, but not NK6 homeobox 1 and paired box 6. A quantitative analysis was performed in the adult pancreas: there was an average of 1.17 + 1.17 epsilon cells per islet, the relative epsilon cell volume was 0.14 + 0.16% and the epsilon cell mass was 0.13 + 0.15 g. Neither sex nor age affected the epsilon cell mass, although there was a significant inverse correlation with BMI. CONCLUSIONS/INTERPRETATION: During fetal development epsilon cells show an ontogenetic and morphogenetic pattern that is distinct from that of alpha and beta cells.


Asunto(s)
Ghrelina/metabolismo , Páncreas/crecimiento & desarrollo , Páncreas/metabolismo , Adulto , Animales , Femenino , Feto , Edad Gestacional , Cabras , Cobayas , Humanos , Inmunohistoquímica , Ratones , Páncreas/citología , Páncreas/embriología , Embarazo , Primer Trimestre del Embarazo , Conejos , Donantes de Tejidos
14.
Am J Transplant ; 9(10): 2372-82, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19681816

RESUMEN

Islet transplantation is an effective therapy for restoring normoglycemia in type-1 diabetes, but long-term islet graft function is achieved only in a minority of cases. Noninvasive magnetic resonance imaging of pancreatic islets is an attractive option for "real-time" monitoring of graft evolution. So far, previous studies have been performed in the absence of a standardized labeling procedure and, besides a feasibility study in patients, the effectiveness and safety of various labeling approaches were tested only with high field magnets (4.7 T). In this study, we addressed: (a) standardization of a labeling procedure for human islets with clinically-approved contrast agent Endorem, (b) safety aspects of labeling related to inflammation and (c) quality of imaging both at 7 T and 1.5 T. We have highlighted that the ratio of Endorem/islet is crucial for reproducible labeling, with a ratio of 2.24 ug/IEQ, allowing successful in vivo imaging both with 1.5 T and 7.0 T magnets up to 143 days after intrahepatic transplant. With this standardized labeling procedure, labeled islets are neither inflamed nor more susceptible to inflammatory insults than unlabeled ones. This report represents an important contribution towards the development of a standardized and safe clinical protocol for the noninvasive imaging of transplanted islets in humans.


Asunto(s)
Diabetes Mellitus Tipo 1/cirugía , Trasplante de Islotes Pancreáticos , Hígado/patología , Imagen por Resonancia Magnética/métodos , Animales , Medios de Contraste , Diabetes Mellitus Tipo 1/fisiopatología , Estudios de Factibilidad , Perfilación de la Expresión Génica , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Reproducibilidad de los Resultados
15.
Am J Transplant ; 8(6): 1303-11, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18444915

RESUMEN

In this study we analyzed the role of CCL2, a member of the chemokine family, in early graft damage. Using simultaneous kidney-pancreas transplantation (SPK) as a model, we showed that brain death significantly increases circulating CCL2 levels in humans. We found that in such situations, high donor CCL2 levels (measured before organ recovery and at the onset of cold preservation) correlate with increased postreperfusion release of CCL2 by both the graft and recipient throughout the week following transplantation (n = 28). In a retrospective study of 77 SPK recipients, we found a significant negative association between high donor levels of CCL2 and graft survival. Decreased survival in these patients is related to early posttransplant complications, including a higher incidence of pancreas thrombosis and delayed kidney function. Taken together our data indicate that high CCL2 levels in the donor serum predict both an increase in graft/recipient CCL2 production and poor graft survival. This suggests that the severity of the inflammatory response induced by brain death influences the posttransplant inflammatory response, independent of subsequent ischemia and reperfusion.


Asunto(s)
Muerte Encefálica/inmunología , Quimiocina CCL2/sangre , Supervivencia de Injerto/inmunología , Trasplante de Riñón/inmunología , Trasplante de Páncreas/inmunología , Adulto , Quimiocina CCL2/inmunología , Funcionamiento Retardado del Injerto , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/cirugía , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/cirugía , Femenino , Humanos , Fallo Renal Crónico/etiología , Fallo Renal Crónico/cirugía , Masculino , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Donantes de Tejidos , Tolerancia al Trasplante
16.
Cell Transplant ; 17(12): 1361-70, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19364073

RESUMEN

Although in a clinical setting islet transplantation is normally performed by percutaneous intrahepatic infusion, the kidney capsule has been the site of choice in nearly all the studies using mice. In the present study, we extensively characterized the mouse model of intraportally transplanted islets with the purpose to propose it as a model to study islet transplantation. C57BL/6 (n = 78) and BALB/C (n = 53) recipients were transplanted with 400 autologous islets alternatively through the portal vein (PV-Tx) or under the kidney capsule (KC-Tx). Glucose concentration during the first hour after syngeneic islet infusion was associated with subsequent long-term function confirming that early events have long-term effects on graft function. In both strains tested the probability to achieve islet function was significantly lower for PV-Tx than KC-Tx. Also in allogeneic models (C57BL/6 to BALB/C, n = 104; BALB/C to C57BL/6, n = 77) the probability to achieve primary function was significantly lower for PV-Tx than KC-Tx and the site of transplantation significantly affected the graft survival. Histological evaluation of livers showed the presence of features (embolism, thrombosis, focal areas of liver necrosis) that are absent in the kidney subcapsular site. Finally, significant differences in the outcome of PV-Tx were observed between the Th type 1 inflammatory-prone C57BL/6 mouse and the type 2 inflammatory-prone BALB/C mouse. Intraportal islet graft model has some features that are more similar to human clinical islet transplantation and should be used as a model to study not only engraftment but also mechanisms of immune suppression and immune tolerance.


Asunto(s)
Trasplante de Islotes Pancreáticos/fisiología , Hígado , Trasplante Heterotópico , Animales , Diabetes Mellitus Experimental/cirugía , Supervivencia de Injerto , Trasplante de Islotes Pancreáticos/patología , Riñón , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Vena Porta , Trasplante Autólogo , Trasplante Homólogo , Trasplante Isogénico
17.
Andrology ; 6(4): 559-563, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29611369

RESUMEN

The aim of this study was to investigate the role of systemic inflammation by means of the neutrophil-to-lymphocyte ratio (NLR) in men with erectile dysfunction (ED). Complete demographic, clinical, and laboratory data from 279 consecutive men with newly diagnosed ED were analyzed. Health-significant comorbidities were scored with the Charlson Comorbidity Index (CCI). A complete blood count was requested for every man, and the NLR was calculated for every individual. Patients were invited to complete the IIEF questionnaire. Logistic regression models tested the odds (OR, 95% CI) of severe ED (defined as IIEF-EF <11, according to Cappelleri's criteria) after adjusting for age, BMI, comorbidities (CCI >0), metabolic syndrome, NLR, cigarette smoking, and color duplex Doppler ultrasound parameters. Likewise, LNR values were also dichotomized according to the most informative cutoff predicting severe ED using the minimum p value approach. Median [IQR] age of included men was 51 [40-64] years. Of all, 87 (31%) men had severe ED. Men with severe ED were older (median [IQR] age: 61 [47-67] vs. 49 [39-58] years) and had a higher rate of CCI>0 [46/87 (53%) vs. 44/192 (23%) patients]. Thereof, NLR was dichotomized according to the most informative cutoff (NLR>3); patients with severe ED more frequently had NLR>3 as compared to all other ED patients [namely, 18/87 (21%) vs. 13/192 (7%)]. At multivariable logistic regression analysis, NLR>3.0 emerged as an independent predictor (OR [CI] 2.43 [1.06; 5.63]) of severe ED, after accounting for other clinical variables. A NLR>3 increased the risk of having severe ED in our cohort, boosting the already existing evidence linking systemic inflammation to ED. Moreover, this easily obtainable index can be clinically useful in better risk-stratifying patients with ED.


Asunto(s)
Disfunción Eréctil/sangre , Linfocitos , Neutrófilos , Adulto , Anciano , Estudios Transversales , Disfunción Eréctil/inmunología , Humanos , Inflamación/complicaciones , Recuento de Linfocitos , Masculino , Persona de Mediana Edad
18.
Transplantation ; 68(5): 655-62, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10507485

RESUMEN

BACKGROUND: The possibility of performing transplantation several days after explant seems to be a peculiarity of islet grafts, and the opportunity to cryopreserve human islets may permit an indefinite period for modulating the recipient immune system. The aim of the present study was the evaluation of in vitro and in vivo functional properties of cryopreserved human islets. METHODS: We used six consecutive human islet preparations not suitable for an immediate transplantation in diabetic patients because the limited islet mass separated. The in vitro function of cryo and fresh islets was studied by determination of insulin and glucagon secretion in response to such classical stimuli as glucose (16.7 mM), glucose (16.7 mM) + 3-isobutyl-1-methylxanthine (0.1 mM), arginine (10 mM), and tolbutamide (100 microM). In vivo islet function was assessed through intravenous glucose tolerance tests performed at 15, 30, 60, and 90 days after transplantation of 1000 hand-picked fresh or cryopreserved islets in nude mice. RESULTS: Basal secretion of true insulin was significantly higher in cryopreserved islets than in fresh ones. The response of cryopreserved islets to arginine and glucose + isobutyl-1-methylxanthine seemed partially impaired. Proinsulin-like molecule secretion seemed higher in cryopreserved than in fresh islets in response to all secretagogues used, and the difference was statistically significant for arginine. The capacity of human cryopreserved islets to maintain a correct metabolic control in diabetic nude mice was progressively lost in 3 months. CONCLUSIONS: These findings showed that cryopreservation affects the function of isolated human islets, maintaining in vivo function for a limited period of time.


Asunto(s)
Criopreservación , Islotes Pancreáticos/metabolismo , 1-Metil-3-Isobutilxantina/farmacología , Animales , Arginina/farmacología , Diabetes Mellitus Experimental/fisiopatología , Diabetes Mellitus Experimental/cirugía , Glucagón/metabolismo , Glucosa/farmacología , Prueba de Tolerancia a la Glucosa , Humanos , Técnicas In Vitro , Insulina/metabolismo , Secreción de Insulina , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/patología , Trasplante de Islotes Pancreáticos , Masculino , Ratones , Ratones Desnudos , Valores de Referencia , Factores de Tiempo , Trasplante Heterólogo
19.
J Endocrinol ; 147(1): 87-93, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7490541

RESUMEN

It has been shown that peripheral glucagon secreting cells (A-cells) are lost during most of the isolation procedures employed for pig islets. Loss of A-cells decreases intra-islet glucagon levels and cAMP levels in B-cells and might reduce glucose-induced insulin release. This study was designed to test this hypothesis, by evaluating the effects of culture of porcine islets with exogenous glucagon on insulin secretion and on insulin and cAMP content in islets. Islets were isolated from adult 2-year old Large White pigs using an automated method. The number of A-cells was calculated by immunostaining for glucagon in islets before and after isolation and a significant decrease in A-cells was observed. After an overnight culture, islets were cultured for 48 h in a standard medium (CMRL 1066, 10% foetal calf serum, 1% antibiotics, 1% glutamine) alone or in the presence of glucagon at two different concentrations (1.0 and 10.0 microM); exposure to glucagon was either continuous or alternated with periods of incubation in CMRL 1066 alone. After the 48-h culture in standard medium, the islet glucagon response to arginine was almost negligible and significantly lower than that observed in human islets.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Glucagón/farmacología , Insulina/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Animales , Células Cultivadas , Medios de Cultivo , AMP Cíclico/metabolismo , Femenino , Secreción de Insulina , Islotes Pancreáticos/metabolismo , Porcinos
20.
Eur Cytokine Netw ; 6(4): 245-52, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8789290

RESUMEN

Dendritic cells (DC) can be obtained from peripheral blood mononuclear cells (PBMC) by in vitro culture with IL-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF). IL-13 shares properties with IL-4 but its receptor does not involve the common gamma chain present in the receptor complex of IL-4 and other cytokines. The present study was aimed to elucidate whether IL-13 can substitute for IL-4 in DC cultures and to compare the phenotypic and functional characteristics of cells obtained using these two cytokines. Monocyte-enriched PBMC were cultured with GM-CSF and IL-4 or GM-CSF and IL-13. Cell yields and DClike morphology were similar. The cells showed a membrane phenotype typical of DC (MHC II+; CD1a+; CD14-; CD3-; CD20-). IL-13-derived and IL-4-derived DC were similar in terms of macropinocytosis, stimulatory capacity of cord blood lymphocytes in mixed leukocyte reaction (MLR), and responsiveness to chemotactic signals. It is concluded that IL-13 is as effective as IL-4, combined with GM-CSF in sustaining DC differentiation from PBMC and that activation of the common gamma chain-driven transduction pathways is dispensable for DC differentiation and function.


Asunto(s)
Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Interleucina-13/farmacología , Antígenos de Diferenciación/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Dendríticas/inmunología , Interacciones Farmacológicas , Factor Estimulante de Colonias de Granulocitos y Macrófagos/administración & dosificación , Humanos , Técnicas In Vitro , Interleucina-13/administración & dosificación , Interleucina-4/administración & dosificación , Interleucina-4/farmacología , Leucaféresis , Prueba de Cultivo Mixto de Linfocitos , Fenotipo , Pinocitosis
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