Factors predicting early postpartum glucose intolerance in Japanese women with gestational diabetes mellitus: decision-curve analysis.

AIMS: To identify factors predicting early postpartum glucose intolerance in Japanese women with gestational diabetes mellitus, using decision-curve analysis. METHODS: A retrospective cohort study was performed. The participants were 123 Japanese women with gestational diabetes who underwent 75-g oral glucose tolerance tests at 8-12 weeks after delivery. They were divided into a glucose intolerance and a normal glucose tolerance group based on postpartum oral glucose tolerance test results. Analysis of the pregnancy oral glucose tolerance test results showed predictive factors for postpartum glucose intolerance. We also evaluated the clinical usefulness of the prediction model based on decision-curve analysis. RESULTS: Of 123 women, 78 (63.4%) had normoglycaemia and 45 (36.6%) had glucose intolerance. Multivariable logistic regression analysis showed insulinogenic index/fasting immunoreactive insulin and summation of glucose levels, assessed during pregnancy oral glucose tolerance tests (total glucose), to be independent risk factors for postpartum glucose intolerance. Evaluating the regression models, the best discrimination (area under the curve 0.725) was obtained using the basic model (i.e. age, family history of diabetes, BMI ≥25 kg/m2 and use of insulin during pregnancy) plus insulinogenic index/fasting immunoreactive insulin <1.1. Decision-curve analysis showed that combining insulinogenic index/fasting immunoreactive insulin <1.1 with basic clinical information resulted in superior net benefits for prediction of postpartum glucose intolerance. CONCLUSIONS: Insulinogenic index/fasting immunoreactive insulin calculated using oral glucose tolerance test results during pregnancy is potentially useful for predicting early postpartum glucose intolerance in Japanese women with gestational diabetes.

High speed prototype quantum key distribution system and long term field trial.

Securing information in communication networks is an important challenge in today's world. Quantum Key Distribution (QKD) can provide unique capabilities towards achieving this security, allowing intrusions to be detected and information leakage avoided. We report here a record high bit rate prototype QKD system providing a total of 878 Gbit of secure key data over a 34 day period corresponding to a sustained key rate of around 300 kbit/s. The system was deployed over a standard 45 km link of an installed metropolitan telecommunication fibre network in central Tokyo. The prototype QKD system is compact, robust and automatically stabilised, enabling key distribution during diverse weather conditions. The security analysis includes an efficient protocol, finite key size effects and decoy states, with a quantified key failure probability of ε = 10⁻¹°.

Efficacy and safety of once-weekly dulaglutide in combination with sulphonylurea and/or biguanide compared with once-daily insulin glargine in Japanese patients with type 2 diabetes: a randomized, open-label, phase III, non-inferiority study.

AIMS: To evaluate 0.75 mg of dulaglutide, a once-weekly glucagon-like peptide-1 receptor agonist, compared with once-daily insulin glargine for glycaemic control in Japanese patients with type 2 diabetes (T2D). METHODS: In this phase III, randomized, open-label, parallel-group, 26-week study, 361 patients with inadequately controlled T2D receiving sulphonylureas and/or biguanides, aged ≥20 years, with glycated haemoglobin (HbA1c) levels 7.0-10.0% (53-86 mmol/mol), inclusive, were randomized (1 : 1) to receive dulaglutide or glargine. Participants and investigators were not masked to treatment allocation. The primary measure was change from baseline in HbA1c at 26 weeks, analysed using a mixed-effects model for repeated measures, with a predefined non-inferiority margin of 0.4%. RESULTS: At week 26, least-squares (LS) mean (standard error) reductions in HbA1c were -1.44 (0.05)% [-15.74 (0.55) mmol/mol] in the dulaglutide group and -0.90 (0.05)% [-9.84 (0.55) mmol/mol] in the glargine group. The mean between-group treatment difference in HbA1c was -0.54% (95% CI -0.67, -0.41) [-5.90 mmol/mol (95% CI -7.32, -4.48)]; p < 0.001. Dulaglutide significantly reduced body weight compared with glargine at week 26 (LS mean difference -1.42 kg, 95% CI -1.89, -0.94; p < 0.001). The most frequent adverse events with dulaglutide treatment were nasopharyngitis and gastrointestinal symptoms. The incidence of hypoglycaemia was significantly lower with dulaglutide [47/181 (26%)] compared with glargine [86/180 (48%)], p < 0.001. CONCLUSION: In Japanese patients with T2D uncontrolled on sulphonylureas and/or biguanides, once-weekly dulaglutide was superior to once-daily glargine for reduction in HbA1c at 26 weeks. Although dulaglutide increased gastrointestinal symptoms, it was well tolerated, with an acceptable safety profile.

Long-term treatment with empagliflozin as add-on to oral antidiabetes therapy in Japanese patients with type 2 diabetes mellitus.

AIMS: To evaluate the safety and efficacy of empagliflozin for 52 weeks as add-on to one other oral antidiabetes therapy in Japanese patients with type 2 diabetes mellitus (T2DM). METHODS: Patients on biguanide (n = 133), thiazolidinedione (n = 273), α-glucosidase inhibitor (n = 139), dipeptidyl-peptidase-4 inhibitor (n = 139) or glinide (n = 140) were randomized 1 : 1 to receive empagliflozin 10 or 25 mg double-blind as add-on therapy for 52 weeks. Patients on sulphonylurea (SU; n = 336) were randomized 2 : 2 : 1 to receive empagliflozin 10 or 25 mg double-blind or open-label metformin as add-on therapy for 52 weeks. The primary objective was to evaluate safety. Change from baseline in glycated haemoglobin (HbA1c) at week 52 was a secondary endpoint. RESULTS: Adverse events (AEs) were reported in 67.6-84.6% of patients receiving empagliflozin. Confirmed hypoglycaemic AEs (plasma glucose ≤70 mg/dl and/or requiring assistance) were reported in 4.4 and 6.6%, respectively, of patients receiving empagliflozin 10 and 25 mg as add-on to SU and in 0.0 to 2.9%, respectively, of patients receiving empagliflozin 10 and 25 mg as add-on to other therapies. Baseline mean ± standard deviation HbA1c ranged from 7.51 ± 0.73 to 8.06 ± 0.76% across background therapy groups. At week 52, adjusted mean ± standard error changes from baseline in HbA1c ranged from -0.77 ± 0.06 to -1.00 ± 0.06% in patients receiving empagliflozin. CONCLUSIONS: In Japanese patients with T2DM, empagliflozin 10 and 25 mg as add-on to one other oral antidiabetes therapy for 52 weeks were well tolerated and were associated with clinically meaningful reductions in HbA1c.

A gene encoding a transmembrane protein is mutated in patients with diabetes mellitus and optic atrophy (Wolfram syndrome).

Wolfram syndrome (WFS; OMIM 222300) is an autosomal recessive neurodegenerative disorder defined by young-onset non-immune insulin-dependent diabetes mellitus and progressive optic atrophy. Linkage to markers on chromosome 4p was confirmed in five families. On the basis of meiotic recombinants and disease-associated haplotypes, the WFS gene was localized to a BAC/P1 contig of less than 250 kb. Mutations in a novel gene (WFS1) encoding a putative transmembrane protein were found in all affected individuals in six WFS families, and these mutations were associated with the disease phenotype. WFS1 appears to function in survival of islet beta-cells and neurons.

Real-world treatment patterns and outcomes of abemaciclib for the treatment of HR + , HER2- metastatic breast cancer patients in Japan.

INTRODUCTION: This study described, in routine clinical practice in Japan, the patient characteristics, treatment patterns, and outcomes of female patients with HR + /HER2- metastatic breast cancer (MBC) who started abemaciclib treatment. METHODS: Clinical charts were reviewed for patients starting abemaciclib in 12/2018-08/2021 with a minimum of 3 months follow-up data post-abemaciclib initiation regardless of abemaciclib discontinuation. Patient characteristics, treatment patterns, and tumor response were descriptively summarized. Kaplan-Meier curves estimated progression-free survival (PFS). RESULTS: 200 patients from 14 institutions were included. At abemaciclib initiation, median age was 59 years, and the Eastern Cooperative Oncology Group performance status score was 0/1/2 for 102/68/5 patients (58.3/38.9/2.9%), respectively. Most had an abemaciclib starting dose of 150 mg (92.5%). The percentage of patients receiving abemaciclib as 1st, 2nd, or 3rd line treatment was 31.5%, 25.8%, and 25.2%, respectively. The most frequent endocrine therapy drugs used with abemaciclib were fulvestrant (59%) and aromatase inhibitors (40%). Evaluation of tumor response was available for 171 patients, 30.4% of whom had complete/partial response. Median PFS was 13.0 months (95% CI 10.1-15.8 months). CONCLUSIONS: In a routine clinical practice setting in Japan, patients with HR + , HER2- MBC appear to benefit from abemaciclib treatment in terms of treatment response and median PFS, with the results broadly reflecting the evidence demonstrated in clinical trials.

Cytomegalovirus ventriculoencephalitis in a reduced- intensity conditioning cord blood transplant recipient.

Cytomegalovirus (CMV) encephalitis most commonly occurs in patients with advanced human immunodeficiency virus infection and profound CD4 cell depletion and is rare in transplant recipients. We describe a patient with pathologically proven CMV ventriculoencephalitis that occurred after human herpesvirus-6 limbic encephalitis, following reduced-intensity conditioning cord blood transplantation (CBT). At approximately day 150 after CBT, the patient became acutely confused after steroid therapy for grade III acute graft-versus-host disease. Fluid-attenuated inversion recovery magnetic resonance imaging of the brain revealed a communicating hydrocephalus with abnormal periventricular hyperintensity. Neuropathologic examination of the brain at autopsy revealed necrotizing CMV ventriculoencephalitis, limbic encephalitis, and multifocal necrotizing leukoencephalopathy. This case represents the first report of CMV encephalitis following CBT and serves to highlight the interrelationship between viruses in transplant recipients.

Increased insulin demand promotes while pioglitazone prevents pancreatic beta cell apoptosis in Wfs1 knockout mice.

AIMS/HYPOTHESIS: The WFS1 gene encodes an endoplasmic reticulum (ER) membrane-embedded protein called Wolfram syndrome 1 protein, homozygous mutations of which cause selective beta cell loss in humans. The function(s) of this protein and the mechanism by which the mutations of this gene cause beta cell death are still not fully understood. We hypothesised that increased insulin demand as a result of obesity/insulin resistance causes ER stress in pancreatic beta cells, thereby promoting beta cell death. METHODS: We studied the effect of breeding Wfs1 ( -/- ) mice on a C57BL/6J background with mild obesity and insulin resistance, by introducing the agouti lethal yellow mutation (A ( y ) /a). We also treated the mice with pioglitazone. RESULTS: Wfs1 ( -/- ) mice bred on a C57BL/6J background rarely develop overt diabetes by 24 weeks of age, showing only mild beta cell loss. However, Wfs1 ( -/- ) A ( y ) /a mice developed selective beta cell loss and severe insulin-deficient diabetes as early as 8 weeks. This beta cell loss was due to apoptosis. In Wfs1 ( +/+ ) A ( y ) /a islets, levels of ER chaperone immunoglobulin-binding protein (BiP)/78 kDa glucose-regulated protein (GRP78) and phosphorylation of eukaryotic translation initiation factor 2, subunit alpha (eIF2alpha) apparently increased. Levels of both were further increased in Wfs1 ( -/- ) A ( y ) /a murine islets. Electron micrography revealed markedly dilated ERs in Wfs1 (-/-) A ( y ) /a murine beta cells. Interestingly, pioglitazone treatment protected beta cells from apoptosis and almost completely prevented diabetes development. CONCLUSIONS/INTERPRETATION: Wfs1-deficient beta cells are susceptible to ER stress. Increased insulin demand prompts apoptosis in such cells in vivo. Pioglitazone, remarkably, suppresses this process and prevents diabetes. As common WFS1 gene variants have recently been shown to confer a risk of type 2 diabetes, our findings may be relevant to the gradual but progressive loss of beta cells in type 2 diabetes.

Significance of Granulocyte Colony-Stimulating Factor-Combined High-Dose Cytarabine, Cyclophosphamide, and Total Body Irradiation in Allogeneic Hematopoietic Cell Transplantation for Myeloid Malignant Neoplasms.

Allogeneic hematopoietic cell transplant (HCT) is a curative procedure for myeloid malignant neoplasms, but relapse after HCT remains critical. A conditioning regimen involving granulocyte colony-stimulating factor-combined high-dose cytarabine, cyclophosphamide, and total body irradiation (G-CSF-combined high-dose cytarabine/cyclophosphamide/total-body irradiation [HDCA/CY/TBI]) was reported to improve outcomes after cord blood transplant (CBT) for myeloid malignant neoplasms, but this regimen was not previously evaluated among patients undergoing bone marrow transplant (BMT) or peripheral blood stem cell transplant (PBSCT). METHODS: We retrospectively analyzed 28 patients who underwent allogeneic HCT including BMT from a related (1 patient) or unrelated donor (9 patients), PBSCT from a related donor (7 patients), or single-unit CBT from an unrelated donor (11 patients) after a G-CSF-combined HDCA/CY/TBI regimen. RESULTS: All patients achieved neutrophil and platelet engraftment, which were significantly more rapid in the BMT/PBSCT group than in the CBT group. Eighteen patients were alive at a median follow-up of 54.3 months. The 3-year relapse and nonrelapse mortality rates were 28.6% and 7.1%, respectively, which were similar between the BMT/PBSCT and CBT groups. Overall survival and disease-free survival at 5 years after HCT were 62.6% and 64.3%, respectively, which were also similar between the BMT/PBSCT and CBT groups. Only disease status at HCT had a significant impact on overall survival and disease-free survival (86.7% with standard risk vs 38.5% with high risk and 86.7% with standard risk vs 38.5% with high risk, respectively). CONCLUSION: A G-CSF-combined HDCA/CY/TBI regimen is a promising conditioning in patients with myeloid malignant neoplasms who undergo not only CBT but also BMT or PBSCT.

Enhanced recovery after surgery for gastric cancer and an assessment of preoperative carbohydrate loading.

BACKGROUND: We previously reported on the feasibility of enhanced recovery after surgery (ERAS) protocol for gastric cancer with a prospective phase II study, but the superiority of this approach over non-ERAS perioperative management remains unclear. Preoperative carbohydrate loading, an important element of the ERAS protocol, has been shown to reduce insulin resistance, but its effects on clinical endpoints in gastric cancer surgery remain controversial. The aim of this study was to clarify the efficacy of the ERAS protocol for gastric cancer surgery, with particular focus on preoperative carbohydrate loading. METHODS: In this ERAS case-control study, we enrolled 121 patients as a case group and 259 patients undergoing gastrectomy for gastric cancer with our conventional perioperative management as a control group. Matched-pair analysis was performed to balance the patients' characteristics for comparison analysis. RESULTS: After matching, 108 patients were included in each group. Postoperative hospital stay was significantly shorter in the ERAS group than in the control group (8 days vs. 9 days, p < 0.001), while the incidence of Clavien-Dindo classification grade II or more postoperative complication was similar between the groups (11.1% vs. 15.7%, p = 0.325). No significant differences were found in serum albumin level, body weight, or grip strength between the groups before surgery and at 1 week and 1 month after surgery. CONCLUSION: Use of the ERAS protocol for gastric cancer shortened the length of postoperative hospital stay without increasing complications. Preoperative carbohydrate loading didn't improve the postoperative nutritional status or maintain the muscle strength postoperatively.

Quantum key distribution with hacking countermeasures and long term field trial.

Quantum key distribution's (QKD's) central and unique claim is information theoretic security. However there is an increasing understanding that the security of a QKD system relies not only on theoretical security proofs, but also on how closely the physical system matches the theoretical models and prevents attacks due to discrepancies. These side channel or hacking attacks exploit physical devices which do not necessarily behave precisely as the theory expects. As such there is a need for QKD systems to be demonstrated to provide security both in the theoretical and physical implementation. We report here a QKD system designed with this goal in mind, providing a more resilient target against possible hacking attacks including Trojan horse, detector blinding, phase randomisation and photon number splitting attacks. The QKD system was installed into a 45 km link of a metropolitan telecom network for a 2.5 month period, during which time the system operated continuously and distributed 1.33 Tbits of secure key data with a stable secure key rate over 200 kbit/s. In addition security is demonstrated against coherent attacks that are more general than the collective class of attacks usually considered.

Glucokinase and NIDDM. A candidate gene that paid off.

Glucokinase, the major enzyme that phosphorylates glucose upon entry into liver and islet beta-cells, has been considered a prime candidate for inherited defects predisposing to NIDDM. Now that the human gene has been isolated, this question has been addressed directly. Polymorphic markers flanking the gene were identified. These markers (microsatellites) are composed of variable numbers of dinucleotide repeats that vary in size, resulting in different alleles. Variably sized alleles can be typed rapidly from genomic DNA of individuals by the PCR. Studies of inheritance of glucokinase genes have revealed significant linkage in families with early-onset NIDDM, or MODY, and mutations have been identified within the coding region of the gene in some families. These studies are extremely encouraging, as they indicate that genes can be identified even in this heterogeneous genetic disorder. This study considers the phenotypes that result from glucokinase defects and the relationship of MODY to NIDDM, and it estimates the role of glucokinase defects in NIDDM in general.

Glucokinase gene variants in the common form of NIDDM.

To determine whether a structural defect in glucokinase could be a primary cause of glucose intolerance in the common form of NIDDM, the prevalence of mutations in the gene in 60 American black NIDDM patients was investigated. First, by Southern blot analysis of DNA from a subset of randomly selected subjects (n = 20), no gross deletions, insertions, or rearrangements of the gene were detected. Next, the 5'-untranslated and coding regions of the gene were amplified directly from genomic DNA by the polymerase chain reaction. PCR products were screened for mutations by using single-strand conformational polymorphism analysis. A total of nine variants were identified, with two in the 5'-UT regions of islet exon 1, two in the 5'-UT region of liver exon 1, and five in the coding regions. For islet exon 1, 5 of 60 NIDDM patients had both variants in the 5'-UT region; and for liver exon 1, two variants each occurred in 1 of 60 NIDDM patients. The coding region variants included a missense mutation in islet exon 1, substitution of Ala11 (GCC) with Thr11 (ACC), found in 2 patients. The biological consequences of this mutation and the mutations in the 5'-UT portion of the gene have yet to be determined. The rest of the variants were third base pair changes of codons, i.e., silent. A common polymorphism, which was in linkage equilibrium with microsatellite repeats GCK1 and GCK2, was found in intron 9, and a variant in intron 2 in both alleles of 1 patient.(ABSTRACT TRUNCATED AT 250 WORDS)

Polymorphic microsatellite repeat markers at the glucokinase gene locus are positively associated with NIDDM in Japanese.

To assess the possible role of glucokinase defects contributing to a genetic susceptibility to NIDDM in Japanese, allelic frequencies of two microsatellite repeat polymorphisms, one in the 3'-flanking region (GCK1) and the other in the 5'-flanking region (GCK2) of the human glucokinase gene, were analyzed in subjects with NIDDM and in nondiabetic control subjects. After typing 107 diabetic and 74 nondiabetic subjects, we found four GCK1 alleles (Z, Z2, Z4, Z6) and six GCK2 alleles (0, -4, -2, 2, 4, 8). The frequency distribution of GCK1 alleles was different between the two groups (P = 0.005), although not significant after correction for multiple comparisons. The Z4 allele was found more frequently in diabetic than in nondiabetic subjects (23 vs. 10%, P = 0.002). This was still significant after correction for multiple comparisons (P < 0.05). The frequency distribution of GCK2 alleles was not different between the two groups. However, the -2 allele was more common in diabetic than in nondiabetic subjects (P = 0.044), although not significant after adjusting for multiple comparisons. Clinical characteristics were compared between the diabetic subjects with Z4 and/or -2 allele and those without either of these two alleles. No differences were found in the age of diagnosis, positive family history, mode of therapy, current HbA1c, or daily urinary C-peptide immunoreactivity excretion between the two groups. We demonstrated a significant association between GCK1 and GCK2 alleles and NIDDM. The results indicate that the polymorphic alleles GCK1 and GCK2 could be genetic markers in NIDDM in Japanese, suggesting a relationship between glucokinase defects and the susceptibility to NIDDM in this population.

Human glucagon-like peptide-1 receptor gene in NIDDM. Identification and use of simple sequence repeat polymorphisms in genetic analysis.

Glucagon-like polypeptides, GLP-1-(7-36)-amide and GLP-1-(7-37), are important regulators of insulin synthesis and secretion by islet beta-cells. The hypothesis to be tested in this study was that defects in the islet beta-cell GLP-1 receptor gene contribute to the impaired glucose-regulated insulin secretion of non-insulin-dependent diabetes mellitus (NIDDM). Human islet GLP-1 receptor genomic clones were isolated, and two highly polymorphic simple sequence repeat regions (GLP-1R-CA1 and GLP-1R-CA3) were identified. Polymerase chain reaction assays were developed to define alleles. For GLP-1R-CA1, 14 alleles were observed in African-Americans (heterozygosity [het] = 0.78) and 6 alleles in Caucasians (het = 0.67). For GLP-1R-CA3, 16 alleles were observed in African Americans (het = 0.89) and 8 alleles in Caucasians (het = 0.83). By genotyping all members of the 40 reference Centre d'Etude du Polymorphisme Humain pedigrees at GLP-1R-CA3, the human GLP-1 receptor gene was uniquely placed on chromosome 6p between GLO1 and D6S19, 20.4 cM from human leukocyte antigen. To assess the possible role of the GLP-1 receptor gene in determining the genetic susceptibility to NIDDM, allelic frequencies of GLP-1R-CA1 and GLP-1R-CA3 were compared between African-American NIDDM patients (n = 95) and control subjects (n = 93). The frequencies did not differ between the two groups at either GLP-1R-CA1 or GLP-1R-CA3. The GLP-1 receptor gene simple-sequence repeat polymorphisms were used for linkage analysis in Utah Mormon pedigrees (n = 16) with NIDDM.(ABSTRACT TRUNCATED AT 250 WORDS)

Human islet glucokinase gene. Isolation and sequence analysis of full-length cDNA.

Pancreatic islet glucokinase (ATP:D-hexose-6-phosphotransferase) cDNAs were isolated from a human islet cDNA library in lambda-gt11. One clone (hlGLK2), 2723 bp plus additional poly(A) residues, appeared to be full length because its size was consistent with a single 2.9-kb glucokinase mRNA on Northern-blot analysis of islet RNA. This cDNA contained an open reading frame of 1395 bp from an ATG codon at position 459, encoding a predicted protein of 465 amino acids (52,000 M(r)). Comparison of the nucleotide sequences of the human islet glucokinase cDNA with that of the recently isolated human liver glucokinase cDNA revealed that the two cDNAs differed completely on their 5'-ends, followed by an identical 2204-bp overlap extending to the 3'-ends. The 5'-ends of islet and liver glucokinase cDNAs predicted proteins that differ by 15 NH2-terminal residues. The overall sequence identity (70%) between the first exons of the human islet and rat islet cDNAs suggested that the islet promoter regions, like the liver promoter regions, have been conserved through evolution. Thus, NH2-terminal differences for human liver and islet enzymes might be explained by use of alternate promoters between the two tissues, analogous to the NH2-terminal differences of the rat liver and rat islet enzymes. If so, this relationship predicts important tissue-specific regulatory functions of these regions. Variations in the glucokinase gene are likely to occur in humans. Isolation of a human islet glucokinase cDNA has provided the sequence necessary to determine whether these variants are important determinants in the genetic predisposition for diabetes mellitus.

Developmental regulation of amylin and insulin-gene expression in lean (Fa/Fa) and obese (fa/fa) Zucker rats.

Obese individuals are hyperinsulinemic and insulin resistant. Because amylin is cosecreted with insulin and may contribute to the insulin resistance of obesity, this study tested the hypothesis that insulin and amylin genes are coordinately regulated by obesity and carbohydrate feeding. Insulin and amylin gene expression were measured during the suckling/weaning transition in lean (Fa/Fa) and obese (fa/fa) Zucker rats, a period associated with marked changes in tissue insulin sensitivity. There was a decline in insulin mRNA (-90 +/- 15%, P less than 0.01) and amylin mRNA (-72 +/- 21%, P less than 0.01) content in pancreases of lean rats maintained on a high-fat diet from days 15 to 30, probably reflecting the relative increase in exocrine/endocrine development during this neonatal period and the effects of fat feeding. Weaning on high-carbohydrate versus high-fat diets resulted in enhanced expression of both insulin (P less than 0.05) and amylin (P less than 0.05) mRNAs. In contrast to the decline in pancreatic insulin and amylin mRNA content observed in lean rats, there was an increase in insulin mRNA (421.3 +/- 57.5%, P less than 0.05) and no change in amylin mRNA in obese rats maintained on a high-fat diet from days 15 to 30. There was no enhancement of insulin or amylin gene expression in obese rats with high carbohydrate relative to high-fat feeding, perhaps reflecting maximum rates of transcription in these obese insulin-resistant rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Troglitazone treatment increases plasma vascular endothelial growth factor in diabetic patients and its mRNA in 3T3-L1 adipocytes.

Troglitazone is one of the thiazolidinediones, a new class of oral antidiabetic compounds that are ligands of peroxisome proliferator-activated receptor-gamma. This study on vascular endothelial growth factor (VEGF), also known as vascular permeability factor, was prompted by our clinical observation that the characteristics of troglitazone-induced edema were very similar to those caused by vascular hyperpermeability. When Japanese diabetic patients were screened for plasma VEGF, we found levels to be significantly (P < 0.001) increased in troglitazone-treated subjects (120.1 +/- 135.0 pg/ml, n = 30) compared with those treated with diet alone (29.2 +/- 36.1 pg/ml, n = 10), sulfonylurea (25.8 +/- 22.2 pg/ml, n = 10), or insulin (24.6 +/- 19.0 pg/ml, n = 10). Involvement of troglitazone in increased VEGF levels was further supported by the plasma VEGF levels in five patients before treatment (20.2 +/- 7.0 pg/ml), after 3 months of troglitazone treatment (83.6 +/- 65.9 pg/ml), and 3 months after discontinuation (28.0 +/- 11.6 pg/ml). We further demonstrated that troglitazone, as well as rosiglitazone, at the plasma concentrations observed in patients, increased VEGF mRNA levels in 3T3-L1 adipocytes. VEGF is an angiogenic and mitogenic factor and is currently considered the most likely cause of neovascularization and hyperpermeability in diabetic proliferative retinopathy. Although increased VEGF may be beneficial for subjects with macroangiopathy and troglitazone is currently not available for clinical use, vascular complications, especially diabetic retinopathy, must be followed with great caution in subjects treated with thiazolidinediones.

Isolation of the human LIM/homeodomain gene islet-1 and identification of a simple sequence repeat polymorphism [corrected].

The islet-1 (Isl-1) gene encodes a protein that binds to the enhancer region of the insulin gene. Isl-1 is a member of the LIM/homeodomain family of transcription factors. Because insulin deficiency, either relative or absolute, is a cardinal feature of non-insulin-dependent diabetes mellitus (NIDDM), this study addressed the question of whether mutations in genes that regulate insulin production could be involved. Rat Isl-1 was the first insulin enhancer binding protein to be isolated, and, in this study, the rat gene was used to isolate a partial human islet Isl-1 cDNA and subsequently to isolate genomic clones. A simple sequence repeat was found in the Isl-1 gene, and polymerase chain reaction amplification of this region of genomic DNA revealed 12 alleles in St. Louis African-Americans (het = 0.87), 14 alleles in black Nigerians (het = 0.89), 8 alleles in Japanese (het = 0.69), and 8 alleles in Caucasians (het = 0.81). Genetic linkage analysis uniquely placed Isl-1 on chromosome 5q (D5S395[12.8 cM]Isl-1 [11.6 cM]D5S407). The simple sequence repeat polymorphism at the Isl-1 locus was used to evaluate mutations in this gene as a possible contributor to the pathogenesis of NIDDM. Allelic frequencies did not differ between patients with NIDDM (n = 165) and nondiabetic control subjects (n = 163) in two black populations (St. Louis African-Americans and Nigerians). Linkage analyses in 15 nonglucokinase maturity-onset diabetes of the young pedigrees indicated that linkage could be rejected (LOD score < -3.0) over a distance of 15 cM.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolation, characterization, and chromosomal mapping of the human insulin promoter factor 1 (IPF-1) gene.

Insulin promoter factor 1 (IPF-1) is a homeodomain-containing protein that is thought to be a key regulator of pancreatic islet development and insulin gene transcription in beta-cells. This report describes the isolation and characterization of the human IPF-1 gene. The coding region, which showed 83% nucleotide identity with the mouse IPF-1 gene, was encoded by two exons that extended over a 5-kb region of human genome. The deduced human IPF-1 protein contained 283 amino acids, 1 amino acid less than the mouse IPF-1 protein. The homeodomain region of IPF-1 was encoded by the second exon, and it was highly conserved among species. The human IPF-1 gene was mapped to chromosome 13q12(12.1) by fluorescent in situ hybridization (FISH) analysis. A simple sequence repeat polymorphism (ipf1CA2) was identified in the genomic clone. Polymerase chain reaction (PCR) amplification of this repeat region revealed two alleles (heterozygosity = 0.32). This simple sequence repeat polymorphism, and thus the IPF-1 gene, was incorporated into the human linkage map by genotyping reference Human Polymorphism Study Center (CEPH) pedigrees. Multipoint analysis with the CEPH genotype database placed the gene with equal likelihood between two marker intervals: D13S292-cdx3GA1 and cdx3GA1-D13S289 on chromosome 13, consistent with the results of FISH analysis. Two-point linkage analysis inferred that the most likely location for ipf1CA2 was at theta = 0 from cdx3GA1 locus. The exon-intron boundaries of the IPF-1 gene were sequenced, and primers were synthesized to search the homeodomain region for potential variants in patients with NIDDM. By single-strand conformational polymorphism analysis, no variants were found within this region in 61 Japanese patients, which could contribute to the pathogenesis of NIDDM. The isolation of the human IPF-1 gene, along with characterization of its genomic structure and chromosomal mapping, will now permit the assessment of the role of this gene in the pathogenesis of NIDDM in various populations.