Publications by authors named "Shimajiri Y"

Article Synopsis
  • This text discusses the development of a machine learning model aimed at consistently classifying individuals with type 2 diabetes into specific subtypes based on Ahlqvist's classification, which is important for tailoring treatment strategies.
  • The model was tested using data from two cohorts: one with 619 Japanese individuals for training and testing, and another with 597 individuals for external validation, employing a random forest algorithm with 15 variables.
  • The results showed high accuracy, with a 94% success rate in predicting diabetes subtypes, indicating the model's strong potential for clinical application despite some inconsistencies in Ahlqvist's method over time.
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Programmable RNA editing offers significant therapeutic potential for a wide range of genetic diseases. Currently, several deaminase enzymes, including ADAR and APOBEC, can perform programmable adenosine-to-inosine or cytidine-to-uridine RNA correction. However, enzymes to perform guanosine-to-adenosine and uridine-to-cytidine (U-to-C) editing are still lacking to complete the set of transition reactions.

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We previously reported that intramuscular injections of ubiquitin ligase CBLB inhibitory pentapeptide (Cblin; Asp-Gly-pTyr-Met-Pro) restored lost muscle mass caused by sciatic denervation. Here, we detected Cblin on the basolateral side of Caco-2 cells after being placed on the apical side, and found that cytochalasin D, a tight junction opener, enhanced Cblin transport. Orally administered Cblin was found in rat plasma, indicating that intact Cblin was absorbed in vitro and in vivo.

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Ubiquitin ligase Casitas B-lineage lymphoma-b (Cbl-b) play a critical role in nonloading-mediated skeletal muscle atrophy: Cbl-b ubiquitinates insulin receptor substrate-1 (IRS-1), leading to its degradation and a resulting loss in muscle mass. We reported that intramuscular injection of a pentapeptide, DGpYMP, which acts as a mimic of the phosphorylation site in IRS-1, significantly inhibited denervation-induced skeletal muscle loss. In order to explore the possibility of the prevention of muscle atrophy by diet therapy, we examined the effects of oral administration of transgenic rice containing Cblin (Cbl-b inhibitor) peptide (DGYMP) on denervation-induced muscle mass loss in frogs.

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Intronic regions of eukaryotic genomes accumulate many Transposable Elements (TEs). Intronic TEs often trigger the formation of transcriptionally repressive heterochromatin, even within transcription-permissive chromatin environments. Although TE-bearing introns are widely observed in eukaryotic genomes, their epigenetic states, impacts on gene regulation and function, and their contributions to genetic diversity and evolution, remain poorly understood.

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Hypertension is one of the most critical risk factors accompanying cardiovascular diseases. γ-Aminobutyric acid (GABA) is a non-protein amino acid that functions as a major neurotransmitter in mammals and also as a blood-pressure lowering agent. We previously produced GABA-fortified rice lines of a popular Japonica rice cultivar 'Koshihikari' by genetic manipulation of GABA shunt-related genes.

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Aims/introduction: The Kir6.2 E23K polymorphism was studied with a special reference to secondary sulfonylurea (SU) failure in non-obese patients with type 2 diabetes.

Materials And Methods: We recruited 278 non-obese (body mass index ≤30.

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Aims/introduction: Islet amyloid polypeptide (IAPP) is a main component of islet amyloid in type 2 diabetes and cosecreted from β-cell with insulin. Clinical evidence from the patients with S20G mutation of the IAPP gene, as well as experimental evidence that insulin could inhibit amyloid formation of IAPP, suggests that a gradual reduction of insulin could be related to the cytotoxicity associated with S20G-IAPP through long-term deterioration of β-cells in type 2 diabetes. Our objective was to show an effect of human insulin on S20G-IAPP associated cytotoxicity.

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Gamma-aminobutyric acid (GABA) is a non-protein amino acid commonly present in all organisms. Because cellular levels of GABA in plants are mainly regulated by synthesis (glutamate decarboxylase, GAD) and catabolism (GABA-transaminase, GABA-T), we attempted seed-specific manipulation of the GABA shunt to achieve stable GABA accumulation in rice. A truncated GAD2 sequence, one of five GAD genes, controlled by the glutelin (GluB-1) or rice embryo globulin promoters (REG) and GABA-T-based trigger sequences in RNA interference (RNAi) cassettes controlled by one of these promoters as well, was introduced into rice (cv.

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γ-Aminobutyric acid transaminase (GABA-T) catalyzes the conversion of GABA to succinic semialdehyde. The rice (Oryza sativa) genome possesses four putative GABA-T genes, which exhibit high amino acid identity (73-82%) but differ in length of the N-terminal region. Transient expression of GABA-T-green fluorescent fusion proteins in onion epidermal cells demonstrated that two of the four enzymes were targeted to mitochondria, a third to chloroplasts, and the fourth to cytosol.

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Aim: The aim of the study was to determine whether fasting serum non-esterified fatty acid (NEFA) could be associated with long-term progressive deterioration of insulin secretion in patients with Type 2 diabetes.

Methods: Seventy-seven Japanese patients with Type 2 diabetes (mean BMI 23.3 kg/m(2) ) were followed for 10 years.

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Clinical evaluation of insulin assay system reacting with only human insulin molecule (kit B) was performed by comparing it with conventional insulin assay system (kit A) cross-reacting with insulin analogue as well as human insulin preparation. In vitro, the kit B was confirmed to cross-react with only human insulin, not with insulin analogue preparations such as insulin aspart, lyspro and glargine. In non-insulin treated diabetic patients, postprandial and post-insulin injected serum immunoreactive insulin (IRI) concentrations measured by kit B were almost the same as those measured by the kit A.

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Unlabelled: Aims/Introduction:  In order to clarify the enhanced β-cell dysfunction in type 2 diabetic patients carrying the S20G mutation of the islet amyloid polypeptide gene (S20G-patients), we first estimated the decline of insulin secretion in Japanese type 2 diabetic patients without the S20G mutation (non-S20G-T2D-patients) by long-term observation, and then compared it with that of the S20G-patients.

Materials And Methods:   We followed 70 non-S20G-T2D-patients (body mass index <30 kg/m(2)) for more than 10 years and six S20G-patients for more than 5 years. We measured fasting C-peptide (F-CP) every 1-2 years and carried out a glucagon test at least once during the follow-up period.

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Unlabelled: Aims/Introduction:  Islets in type 2 diabetes are characterized by deposition of islet amyloid polypeptide (IAPP) as well as β-cell dysfunction. The unique amyloidogenic character of human (h)IAPP is associated with cytotoxicity. Autophagy is a ubiquitous system of cellular recycling that contributes to cell survival.

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Transient expression of the transcription factor neurogenin-3 marks progenitor cells in the pancreas as they differentiate into islet cells. We developed a transgenic mouse line in which the surrogate markers secreted alkaline phosphatase (SeAP) and enhanced green florescent protein (EGFP) can be used to monitor neurogenin-3 expression, and thus islet cell genesis. In transgenic embryos, cells expressing EGFP lined the pancreatic ducts.

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Background: Chronic kidney disease (CKD) and metabolic syndrome have been recognized as risk factors for cardiovascular disease. However, there is no information comparing their impact on macroangiopathy in diabetic patients. Thus, we studied the prevalence of CKD and metabolic syndrome in Japanese type 2 diabetic patients and then compared their impact on peripheral arterial disease (PAD) in type 2 diabetic patients.

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Wolbachia, belonging to Alphaproteobacteria, is ubiquitously found in arthropods and filarial nematodes, and is known to manipulate the reproduction of its hosts in various ways, such as feminization, male killing, induction of parthenogenesis or induction of cytoplasmic incompatibility. We found that the Wolbachia infection frequencies of the butterfly Colias erate poliographus were high (85.7-100%) in seven Japanese populations.

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Urine type IV collagen concentrations in type 2 diabetic patients were measured by enzyme immunoassay which has crossreactivity with only intact type IV collagen, and the clinical usefulness for estimating the early phase of diabetic nephropathy was evaluated. Precision of the measurement system was satisfactory for clinical use and the value did not influenced by the presence of sediments in urine. In whole type 2 diabetic patients (N=132), urine type IV collagen concentration (microg/g of creatinine) increased with development of nephropathy and showed significantly increase even in normoalbuminuria when compared with that in normal control subjects (N=117).

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The angiotensin II receptor blocker (ARB) telmisartan has a molecular structure that confers it partial agonist properties similar to those of peroxisome proliferators-activated receptor-gamma molecule, which is thought to modulate tissue response to insulin. In order to investigate the effects of telmisartan on insulin sensitivity and glucose metabolism, we enrolled 14 hypertensive patients under treatment with ARB other than telmisartan who had insulin resistance [homeostasis model for insulin resistance (HOMA-IR)>2.0] but no severe glucose tolerance (HbA1c<6.

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Plasma brain natriutetic peptide (BNP) concentrations in type 2 diabetic patients were measured by newly developed enzyme immunoassay, and their clinical application was evaluated. Precision of the measurement system was satisfactory for clinical use, and the value obtained by this system had good correlation to that by radioimmunoassay. Tubes containing NaF in addition to EDTA, usually used for measurement of plasma glucose and HbA1c in diabetic patients, could be used for the collection of plasma sample.

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Prevalence of metabolic syndrome (MetS) in type 2 diabetes and its association with vascular complications were studied in 637 Japanese type 2 diabetic patients. MetS was diagnosed using criteria proposed by the Japanese study group for the definition of MetS in 2005. The prevalence of MetS in patients studied was higher in males (45.

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Aim: This study was conducted to clarify cell death and survival signals in pancreatic beta-cell lipotoxicity.

Methods: Rat insulinoma INS-1 cells, with or without expression of dominant-negative mutant of Akt (K179M), were cultured with palmitate (C16:0) or oleate (C18:1) and cell numbers were determined by 0.2% eosin dye exclusion assay.

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Betacellulin (BTC), a member of the epidermal growth factor (EGF) family, is an important factor in the growth and/or differentiation of pancreatic beta cells. In this point of view, we determined the transcriptional start site of the human BTC gene and screened the protein-coding region for mutations. The transcriptional start site was located 347 bp upstream from the translational initiation codon.

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We evaluated association between hyperinsulinemia/insulin resistance and microalbuminuria in the insulin-resistant Otsuka Long-Evans Tokushima Fatty (OLETF) rat. OLETF rats showed glomerular hyperfiltration (an increase in creatinine clearance and a decrease in fractional excretion of Na) and microalbuminuria at the insulin-resistant prediabetic stage, and both were related to expression of transforming growth factor (TGF)-beta(1) and extracellular matrix protein such as fibronectin and collagen (a(1)) IV. Cilostazol, a selective type III cyclic nucleotide phosphodiesterase (PDE) inhibitor, normalized glomerular hyperfiltration and microalbuminuria with a parallel decline of TGF-beta(1) and extracellular matrix protein mRNA expression.

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We previously reported that a missense mutation at codon 121 (CGG(Arg) to TGG(Trp), R121W) of PAX4 may be associated with the onset of type 2 diabetes in Japanese. In this study, we determined the frequency of the R121W mutation of PAX4 and characterized the prodiabetic phenotype in a population-based study. Healthy 372 residents participated in annual health check-ups in Nishihara (Okinawa, Japan) and unrelated 193 type 2 diabetic patients from the outpatient clinic of Ryukyu University Hospital were enrolled.

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