Obtaining accurate and calibrated coil models for transcranial magnetic stimulation using magnetic field measurements.

Currently, simulations of the induced currents in the brain produced by transcranial magnetic stimulation (TMS) are used to elucidate the regions reached by stimuli. However, models commonly found in the literature are too general and neglect imperfections in the windings. Aiming to predict the stimulation sites in patients requires precise modeling of the electric field (E-field), and a proper calibration to adequate to the empirical data of the particular coil employed. Furthermore, most fabricators do not provide precise information about the coil geometries, and even using X-ray images may lead to subjective interpretations. We measured the three components of the vector magnetic field induced by a TMS figure-8 coil with spatial resolutions of up to 1 mm. Starting from a computerized tomography-based coil model, we applied a multivariate optimization algorithm to automatically modify the original model and obtain one that optimally fits the measurements. Differences between models were assessed in a human brain mesh using the finite-elements method showing up to 6% variations in the E-field magnitude. Our calibrated model could increase the precision of the estimated E-field induced in the brain during TMS, enhance the accuracy of delivered stimulation during functional brain mapping, and improve dosimetry for repetitive TMS. Graphical Abstract Geometrical model of TMS coil based on TAC images is optimally deformed to match magnetic field measurements. The calibrated model's induced electric field in the brain differs from the original.

[Argentinean consensus guidelines on the use of monoclonal antibodies in patients with migraine]. / Consenso sobre el uso de anticuerpos monoclonales en la migraña en Argentina.

INTRODUCTION: Migraine is a very prevalent disorder that is estimated to affect about 15% of adult subjects. Recently, the efficacy and safety of monoclonal antibodies that act on the calcitonin gene-related peptide pathway (MA-CGRP) has been evaluated in migraine. Several groups around the world have developed consensus guidelines about the use of monoclonal antibodies, however, in some regions is difficult to extrapolate the recommendations. AIM: To provide recommendations for the use of MA-CGRP in migraine in Argentina. DEVELOPMENT: A group of neurology experts from Argentina, by using the online surveys methodology as well as face to face meetings developed the intended consensus for the use of MA-CGRP in migraine in Argentina. Recommendations were established based on published evidence and the expert opinion. Recommendations focused on how, when, treatment duration and patients follow up. CONCLUSION: The recommendations of this consensus guidelines attempt to optimize the use of MA-CGRP in migraine in Argentina.

TITLE: Consenso sobre el uso de anticuerpos monoclonales en la migraña en Argentina.Introducción. La migraña es un trastorno muy prevalente que se estima que afecta a alrededor del 15% de los sujetos adultos. Durante los últimos años, se ha evaluado la eficacia y la seguridad de los anticuerpos monoclonales que actúan sobre la vía del péptido relacionado con el gen de la calcitonina (AM-PRGC) en la migraña. Diversos grupos de trabajo internacionales han intentado clarificar y normatizar el uso de estos medicamentos en la migraña. Sin embargo, en muchas ocasiones se extrapolan datos de otras regiones que no contemplan la realidad de cada lugar o son difíciles de implementar. Objetivo. Proveer recomendaciones sobre el uso de AM-PRGC en pacientes con migraña en Argentina. Desarrollo. Un grupo de expertos de Argentina conformado por neurólogos, mediante metodología de ronda de encuestas en la distancia y reuniones presenciales, llevó adelante la elaboración del consenso pretendido para el uso de AM-PRGC en pacientes con migraña en Argentina. Se establecieron las recomendaciones basadas en la evidencia publicada y en el criterio de los expertos que participaron. Las recomendaciones se enfocaron en el momento de usar los AM-PRGC en la migraña tanto crónica como episódica, la duración, los cuidados y el entorno para hacerlo. Conclusión. Las recomendaciones establecidas en el presente consenso permitirán optimizar el manejo de los AM-PRGC en pacientes con migraña en Argentina.

Islet transplantation in Italy.

Two centers have now an active islet transplant program in Italy, both placed in Milan: the San Raffaele Scientific Institute and the Niguarda Hospital. Up to 2018 in Italy about 200 patients affected by type 1 diabetes mellitus received an islet allotransplantation and about 100 patients received an islet auto-transplantation after a partial or total pancreatectomy. In spite of this large volume of activities, there is not a specific reimbursement fee for islet isolation and current reimbursement based on the Diagnosis-related group covers only partially the hospitalization and the islet transplantation costs.

Intramuscular islet allotransplantation in type 1 diabetes mellitus.

OBJECTIVE: Alternative sites to the liver for islet transplantation have been studied for a long time. Intramuscular islet transplantation appears to be an alternative site to the liver because of the ease of access. First islet autotransplantations were reported in patients after total pancreatectomies. The transplanted islets showed a proper revascularization and their function was observed for up to 2 years after the implant. However, only a few cases of autotransplantation and no allotransplantation have been performed. The aim of this study was to verify the feasibility of islet allotransplantation into muscles. PATIENTS AND METHODS: In four patients affected by type 1 diabetes mellitus in which liver islet allotransplantation was contraindicated, human islets were transplanted into patients' arm muscle with local anesthesia. RESULTS: The surgery was minimally invasive, without complications. In one patient a moderate local inflammatory reaction was observed at the site of the implant, which resolved spontaneously within 4 days. Islet graft function was observed after transplantation in all patients, but it progressively disappeared in 3 out 4 patients within a short time. CONCLUSIONS: In this first ever-reported intramuscular pancreatic islet allotransplantation, the procedure appears feasible but new strategies must be envisaged to significantly improve islet engraftment and the long-term graft function.

Ultrasound characterization of insulin induced lipohypertrophy in type 1 diabetes mellitus.

OBJECTIVE: Subcutaneous insulin absorption is one of the key factors affecting glycemic control in patients with diabetes mellitus under insulin therapy. Insulin-induced subcutaneous lipohypertrophy has been reported to impair insulin regular absorption and hence glycemic control. So far, lipohypertrophy diagnosis has only been clinical. This study aims at evaluating the possible role of ultrasound scan in the assessment of subcutaneous lipohypertrophy in patients affected by type 1 diabetes mellitus. METHODS: A pilot observational retrospective study was performed in 20 patients affected by type 1 diabetes mellitus. In these patients the areas with clinical evidence of lipohypertrophy dependent on the insulin injections were characterized by the presence of tissues that at the ultrasound scan resulted similar to fibrotic tissues (hyperechogenic) or to an interstitial edema or to fat tissues (hypoechogenic). It was utilized a multi frequency linear probe (6-18 MHz). The patients were advised to avoid insulin injections on the areas with lipohypertrophy scanned by the ultrasound and the HbA1c changes were evaluated 3 months later. RESULTS: The lipohypertrophic areas presented at least three different aspects upon ultrasound assessment: the iso-hyperechogenic one, with a predominant fibrotic component; the isoechogenic one, with "large tangles" fibrotic elements and the iso-hypoechogenic aspect with no fibrotic elements. When patients were advised to avoid insulin injections on areas with lipohypertrophy defined by ultrasound scan, 3 months after the first evaluation HbA1c had significantly improved (basal HbA1c 7.87 ± 0.56 versus 7.67 ± 0.52 3 months later, p = 0.029). No significant improvements of the HbA1c were found in the control matched group in which lipohypertrophy was only clinically valued through inspection and palpation. CONCLUSIONS: Ultrasound scan can help identify and characterize the lipohypertrophic areas and this might be useful to improve glycemic control.

A new method to value efficiency of enzyme blends for pancreatic tissue digestion.

Islet transplantation, since the 1990s, has been an example of human cell therapy. Nevertheless, the islet isolation procedure is not completely standardized; in fact, >50% of islet procedures do not eventuate in transplantation due both to the variability of a donor's pancreas and to the unpredictable efficiency of an enzymatic blend. The enzymes used in pancreas isolation to digest several substrates are extracted from Clostridium histolyticum. In particular, they have strong collagenolytic activity compared with vertebrate collagenases. However, several impediments persist in human islet isolation success, probably owing to the variable composition and concentration of collagenases employed during the digestion phase. For islet isolation processes, neutral proteases play important roles. However, they should be considered to be double-edged swords, contributing to tissue dissociation but, sometimes, decreasing islet yield through fragmentation, breakdown, and inactivation. Protease activities cannot be preciously adjusted in a narrow range, there is no approach to determine the optimal dosage and composition of enzymes for extraction of human islets from the pancreas. At this time, available data on commercial enzymatic activity are not sufficient to predict their efficiency for pancreas digestion; consequently, it is difficult to select enzyme batches. For these reasons, we sought to generate an innovative evaluation assay to select enzymes useful for isolation procedures of pancreatic islets.

Missense mutations in the TGM2 gene encoding transglutaminase 2 are found in patients with early-onset type 2 diabetes. Mutation in brief no. 982. Online.

Transglutaminase 2 (TG2 or TGM2) is a multi-functional enzyme which catalyzes transamidation reactions or acts as a G-protein in intracellular signalling. Tgm2-/- Mice lacking TG2 activity are glucose intolerant and show impairment of insulin secretion, suggesting an important physiological role for TG2 in the pancreatic beta cell. We have previously described a TGM2 heterozygous missense mutation ((c.998A>G, p.N333S) in a 14 year-old patient with insulin-treated diabetes and in his diabetic father. The aim of this study was to further investigate the role of TG2 in early-onset type 2 diabetes. We analysed the TGM2 gene in 205 patients with clinically defined Maturity Onset Diabetes of the Young (MODY) or early-onset type 2 diabetes. We found two novel heterozygous mutations (c.989T>G, p.M330R; c.992T>A, p.I331N), which were not detected in 300 normoglycemic controls. All mutations were in residues which are located close to the catalytic site and impaired transamidating activity in vitro. Gene expression of TGM family genes and localization of TG2 in normal human pancreas indicated that TG2 is the only transglutaminase significantly expressed in human pancreatic islet cells. We conclude that reduced TG2 activity can contribute to disorders of glucose metabolism possibly via an impairment of insulin secretion.

Culture medium modulates proinflammatory conditions of human pancreatic islets before transplantation.

A portion of transplanted islets is lost during engraftment as a result of stressful events, involving hypoxia and production of proinflammatory molecules by islets. Two of these molecules (monocyte chemoattractant protein-1, CCL2/MCP-1 and tissue factor, TF) are directly correlated with reduced graft function. We evaluated which factors reduce islet proinflammatory conditions. In particular the effects of different culture media supplemented with proteins or antioxidant agents on CCL2/MCP-1 and TF human islet release were evaluated. We observed that human islets after culture in final wash culture medium (FW) significantly decreased CCL2/MCP-1 release and TF production compared with CMRL and M199. These effects were independent from the type of protein added to the media (human serum, human albumin, fetal calf serum). Glutathione in FW further decreased CCL2/MCP-1 in a dose-dependent manner. Culture conditions can modulate the proinflammatory state of islets, and could be used in clinical islet transplantation to reduce inflammation during engraftment.

Rapamycin induces a caspase-independent cell death in human monocytes.

The immunosuppressive activity of rapamycin (RAPA) and its efficacy as an anti-rejection agent in organ transplantation have been ascribed principally to its anti-proliferative effects on T cells, while the activity on monocytes is partially unknown. In vitro, RAPA reduced monocyte survival by inducing a caspase-independent cell death. RAPA-induced monocyte cell death (RAPA-CD) was impeded by activation of granulocyte macrophage-colony stimulating factor family receptors or toll-like receptor 4, and by exposure to inflammatory cytokines. In vivo, in patients who received RAPA monotherapy as part of pre-conditioning for islet transplantation, RAPA affected survival of myeloid lineage cells. In the peripheral blood, CD33(+) and CD14(+) cells decreased, whereas lymphocytes appeared unaffected. In the bone marrow, myeloid precursors such as CD15(+) and CD15(+)/CD16(+) were selectively and significantly decreased, but no major cytotoxic effects were observed. The RAPA-CD suggests a dependence of monocytes on mammalian target of RAPA pathways for nutrient usage, and this feature implies that RAPA could be selectively useful as a treatment to reduce monocytes or myeloid cells in conditions where these cells negatively affect patient, suggesting a potential anti-inflammatory action of this drug.

Islet isolation for allotransplantation: variables associated with successful islet yield and graft function.

AIMS/HYPOTHESIS: Efficient islet isolation is an important prerequisite for successful clinical islet transplantation. Although progressively improved, islet yield and quality are, however, unpredictable and variable and require standardisation. METHODS: Since 1989 we have processed 437 pancreases using the automated method. The donor characteristics, pancreas procurement, and digestion and purification procedures including a wide enzyme characterisation of these pancreases were analysed and correlated with islet yield and transplant outcome. RESULTS: By univariate analysis, islet yield was significantly associated with donor age (r=0.16; p=0.0009), BMI (r=0.19; p=0.0004), good pancreas condition (p=0.0031) and weight (r=0.15; p=0.0056), total collagenase activity (r=0.22; p=0.0001), adjusted collagenase activity/mg (r=0.18; p=0.0002), collagenase activity/solution volume (r=0.18; p=0.0002) and neutral protease activity/solution volume (r=0.14; p=0.0029). A statistically significant contribution to the variability of islet yield in a multivariate analysis performed on donor variables was found for donor BMI (p=0.0008). In a multivariate analysis performed on pancreas variables a contribution was found for pancreas weight (p=0.0064), and for a multivariate analysis performed on digestion variables we found a contribution for digestion time (p=0.0048) and total collagenase activity (p=0.0001). Twenty-four patients with type 1 diabetes received single islet preparations from single donors. In these patients, multivariate analyses showed that the reduction in insulin requirement was significantly associated with morphological aspects of islets (p=0.0010) and that 1-month C-peptide values were associated with islet purity (p=0.0071). CONCLUSIONS/INTERPRETATION: These data provide baseline donor, digestion and purification selection criteria for islet isolation using the automated method and indicate that the morphological aspect may be a clinically relevant measure of islets on which the decision for transplant can be based.

Islet transplantation in type 1 diabetic patients.

Islet transplantation has been shown to improve overall glucose homeostasis and retard the progression of complications in type I diabetic patients. Also the percentage of recipients achieving complete insulin independence has progressively increased over recent years. An unsolved problem is whether the short-term graft function is secondary to progressive islet exhaustion or to recurrent autoimmunity despite the immunosuppressive therapy. The indications for this procedure remain limited to selected type I diabetic patients. The risks of the immunosuppressive therapy are only proposed to type I diabetic recipients with uncontrolled disease, despite all efforts of the diabetologist and the patient (brittle diabetes), or with a poor quality of life due to unawareness hypoglycemia or severe chronic and progressive complications.

In vitro modulation of monocyte chemoattractant protein-1 release in human pancreatic islets.

Islet transplantation is a new approach to treat type 1 diabetic patients. Despite its great potential and progressively increasing success rate, islet engraftment still represents an unsolved problem. Only part of the transplanted beta-cell mass survives after infusion due to hypoxia and inflammatory reactions, principally mediated by macrophages. We have demonstrated that human islets release monocyte chemoattractant protein-1 (MCP-1), one of the most powerful macrophage chemokines, which may impair the fate of a transplant. In this study we have attempted to modulate in vitro MCP-1 release by human islets. Human islets isolated using the automated method were cultured in CMRL or M199 standard culture media alone or supplemented with (1) two intracellular kinase inhibitors (10 micromol/L RO8220, a protein kinase C inhibitor, and rcAMP 20 micromol/L, a protein kinase A inhibitor) or (2) two antioxidant and cell-protective agents (vitamin E, vitamin B); or (3) immunosuppressive drugs (0.001 to 10 ng/mL cyclosporine, 0.1 to 100 ng/mL rapamycin, 0.1 to 10 ng/mL tacrolimus, 0.001 to 10 ng/mL mycophenolate acid). We observed that the only culture condition that significantly decreased MCP-1 in human islets were CMRL (31 +/- 12 in CMRL vs 539 +/- 184 pg/mL, in M199, P <.05) or cyclosporine (514 +/- 83 pg/mL in control islet vs 307 +/- 13, 231 +/- 44, 192 +/- 4, 242 +/- 113, 169 +/- 15 pg/mL in islet plus cyclosporine ranging from 0.001 to 10 ng/mL, respectively, P >.05). The capacity of in vitro factors to decrease human islet MCP-1 release suggests strategies to increase the success of islet transplantation.

Identification of in vitro parameters predictive of graft function: a study in an animal model of islet transplantation.

The quality of human islets is one of the factors decisive for the success of human islet transplantation. Several parameters have been proposed to characterize islet quality, but none of them has been able to predict the fate of a transplant. The aim of our study was to correlate a panel of in vitro parameters for islet viability with their in vivo function after transplantation in nude mice. Islets were obtained after enzymatic digestion of a human pancreas; they were purified from exocrine tissue using a continuous-density gradient. Two aliquots of islets (1000 and 2000 islets) were transplanted under the kidney capsule of diabetic nude mice. The animals were followed for 1 month with repeated measurements of blood glucose and body weight. One month after transplantation, mice were killed and their graft harvested for histologic analysis. In parallel we studied in vitro islet viability with propidium iodide and fura-2, their insulin content, their purity, and their insulin response to glucose upon static incubation. Ten islet preparations were transplanted: 3 out of 10 preparations did not restore normoglycemia; 4 out of 10 normalized glycemia only in mice receiving 2000 islets, and 3 out of 10 fully restore normoglycemia in all mice. The purity of preparations (R(2) = 0.63 and 0.85, respectively, with 1000 and 2000 islets) and the insulin content (R(2) = 0.75 with 2000 IE) correlated with transplant success. These data show that purity of islet preparations and their insulin content should be useful parameters for the selection of islet preparations for transplant purposes.

Idiopathic intracranial hypertension (pseudotumor cerebri): descriptive epidemiology, clinical features, and visual outcome in Parma, Italy, 1990 to 1999.

PURPOSE: To ascertain the annual incidence rate and the clinical features, other than visual outcome, of idiopathic intracranial hypertension (IIH) in Parma, northern Italy. METHODS: Neurologic care of people living in the Parma area is entirely provided by one private and two public hospitals. Medical records related to IIH were retrospectively reviewed for all Parma residents from 1990 through 1999. RESULTS: Ten patients (8 women and 2 men) were identified as having IIH according to modified Dandy criteria. Their age ranged from 16 to 53 years with a mean of 36 years at diagnosis. The annual age-adjusted rate per 100,000 is 0.28 for the total population. For women in reproductive age, the annual incidence rate is 0.65/100,000. For overweight women in reproductive age, the annual incidence rate is 2.7/100,000. CONCLUSIONS: The incidence rate found in this study is lower than the incidence reported in previous US and Libyan studies. A significant difference in overweight distribution is observed comparing percentage of body weight between US and Parma populations. As overweight and obesity are important factors contributing to IIH development, it is possible that their low percentage in the Parma population may, at least partially, explain the low IIH incidence observed.

Islet allotransplantation in type 1 diabetic patients.

Islet transplantation was proposed more than 10 years ago as treatment for normalising glucose homeostasis in type 1 diabetic patients. Since the beginning it has aroused great interest among diabetic patients being an easy procedure, burdened by minor complications: islet transplantation in fact consists on a transhepatic percutaneous injection under local anaesthesia. The initial clinical outcomes not came up to expectations, being low the insulin independence rate and the long term graft function in recipients. Recently, thanks to the introduction of new immunosuppression strategies, clinical data greatly improved: insulin independence was reached in all recipients and maintained in more than 70% of them 2 years from the transplant. The need of an immunosuppression therapy limits the indication of islet transplantation to diabetic patients already immunosuppressed for a previous organ transplant or to patients with brittle diabetes, that is not controlled also with the new strategies of insulin treatment, with a poor quality of life and an increased rate of diabetic complications. Other problems are represented by the progressive decrease of graft function during long term follow up, and by the low number of organ donors that limits the number of transplantation feasible per year.

Secretory defects induced by immunosuppressive agents on human pancreatic beta-cells.

Despite the considerable interest for islet and pancreas transplantation, remarkably little is known about the direct effects of immunosuppressive drugs on human beta-cell function. We measured different insulin secretory parameters and insulin gene expression of human islets cultured for 5 days in the presence of mycophenolate mofetil (MMF), cyclosporin A (CsA), tacrolimus (FK506) or a mixture of 3 cytokines. Basal insulin release after exposure to cytokines and FK506 was significantly higher than in control islets. Responsiveness to an acute glucose stimulus did not differ significantly between control and treated islets. However, absolute incremental insulin responses (delta-AUCs) of islets exposed to cytokines or FK506 were significantly higher compared to islets exposed to CsA or MMF, mainly because of the higher basal release. Indeed, maximal over basal release (stimulation index, SI) tended to be lower in islets exposed to FK506 than in control islets. Insulin gene expression was significantly reduced only in islets exposed to CsA. FK506 was, among those tested, the immunosuppressive drug that most profoundly altered the normal insulin secretory pattern of human beta-cells, whereas CsA was the only inhibiting insulin gene expression. Although the abnormalities induced by the immunosoppressive drugs utilized in this study were modest, these in vitro data are consistent with the reported in vivo diabetogenicity of CsA and FK506 and point to MMF as the ideal immunosuppressive agent from a pancreatic beta-cell point of view.

Successful [correction of Succesful] transplantation of human islets in recipients bearing a kidney graft.

AIMS/HYPOTHESIS: Islet transplantation is a minimally invasive approach to curing Type I (insulin-dependent) diabetes mellitus. Success has recently been reported in patients receiving solitary islet transplants but the outcome in patients receiving islets together with, or after, kidney transplants has been limited and unpredictable. METHODS: Here we report successful islet transplantation in a cohort of 15 patients with Type I diabetes who were followed for at least 1 year after islet transplantation, after having already received kidney allografts because of end-stage nephropathy. RESULTS: C-peptide after transplantation was higher than 0.17 nmol/l in all 15 recipients, reflecting the absence of primary non-function. Insulin requirement was reduced by over 50 % in all but one patient, and insulin independence was achieved in 10 (66 %) recipients, five of whom now have stable, prolonged insulin independence, well controlled fasting glycaemia, a substantial first-phase and normal second-phase response to glucose, normal insulin sensitivity (HOMA analyses) and HbA1 c of under 6.2 % (33, 26, 18, 13 and 12 months after transplantation respectively). Of importance for patient management, an assessment of fasting blood glucose and proinsulin values following overnight withdrawal of insulin administration one month after transplantation was a potent predictor of insulin independence, and could be used to decide patients who should have further islet preparations. CONCLUSION/INTERPRETATION: These findings support the use of islet transplantation as a cure for Type I diabetes in patients with severe complications.

Autoantibody response to islet transplantation in type 1 diabetes.

Islet allotransplantation into patients with autoimmune type 1 diabetes represents a reexposure to autoantigen. Here, measurement of antibodies to GAD and IA-2 autoantigens before and after islet transplantation in 36 patients (33 receiving islet plus kidney grafts with cyclosporin and steroid-based immunosuppression, and 3 receiving solitary islet transplants with mycophenolate but cyclosporin-free immunosuppression) demonstrated marked rises in GAD antibodies within 7 days posttransplantation in 5 patients (3 receiving islet after kidney transplants, and 2 receiving solitary islet transplants) and within 30 days in the third patient receiving solitary islet transplantation. GAD antibodies were of the IgG1 subclass, against major autoantigenic epitopes, and in cases of islet after kidney transplants, the responses were short-lived and not accompanied by HLA antibodies. Two of these patients had subsequent marked rises of IA-2 antibodies, and an additional patient had a marked rise in IgM-GAD antibodies 3 years after transplantation. Insulin independence was not achieved in patients with autoantibody elevations and was significantly less frequent in these patients. These data are consistent with a reactivation of autoimmunity that may be dependent on immunosuppression therapy and is associated with impaired graft function.

High glucose causes apoptosis in cultured human pancreatic islets of Langerhans: a potential role for regulation of specific Bcl family genes toward an apoptotic cell death program.

Type 2 diabetes is characterized by insulin resistance and inadequate insulin secretion. In the advanced stages of the disease, beta-cell dysfunction worsens and insulin therapy may be necessary to achieve satisfactory metabolic control. Studies in autopsies found decreased beta-cell mass in pancreas of people with type 2 diabetes. Apoptosis, a constitutive program of cell death modulated by the Bcl family genes, has been implicated in loss of beta-cells in animal models of type 2 diabetes. In this study, we compared the effect of 5 days' culture in high glucose concentration (16.7 mmol/l) versus normal glucose levels (5.5 mmol/l) or hyperosmolar control (mannitol 11 mmol/l plus glucose 5 mmol/l) on the survival of human pancreatic islets. Apoptosis, analyzed by flow cytometry and electron and immunofluorescence microscopy, was increased in islets cultured in high glucose (HG5) as compared with normal glucose (NG5) or hyperosmolar control (NG5+MAN5). We also analyzed by reverse transcriptase-polymerase chain reaction and Western blotting the expression of the Bcl family genes in human islets cultured in normal glucose or high glucose. The antiapoptotic gene Bcl-2 was unaffected by glucose change, whereas Bcl-xl was reduced upon treatment with HG5. On the other hand, proapoptotic genes Bad, Bid, and Bik were overexpressed in the islets maintained in HG5. To define the pancreatic localization of Bcl proteins, we performed confocal immunofluorescence analysis on human pancreas. Bad and Bid were specifically expressed in beta-cells, and Bid was also expressed, although at low levels, in the exocrine pancreas. Bik and Bcl-xl were expressed in other endocrine islet cells as well as in the exocrine pancreas. These data suggest that in human islets, high glucose may modulate the balance of proapoptotic and antiapoptotic Bcl proteins toward apoptosis, thus favoring beta-cell death.