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Aim Familial hypercholesterolemia (FH) is an underdiagnosed autosomal dominant genetic disorder characterized by high levels of plasma low-density lipoprotein cholesterol (LDL-C) from birth. This study aimed to assess the genetic identification of FH in children with high LDL-C levels who are identified in a universal pediatric FH screening in Kagawa, Japan. Method In 2018 and 2019, 15,665 children aged 9 or 10 years underwent the universal lipid screening as part of the annual health checkups for the prevention of lifestyle-related diseases in the Kagawa prefecture. After excluding secondary hyper-LDL cholesterolemia at the local medical institutions, 67 children with LDL-C levels of ≥ 140 mg/dL underwent genetic testing to detect FH causative mutations at four designated hospitals. Results The LDL-C levels of 140 and 180 mg/dL in 15,665 children corresponded to the 96.3 and 99.7 percentile values, respectively. Among 67 children who underwent genetic testing, 41 had FH causative mutations (36 in the LDL-receptor, 4 in proprotein convertase subtilisin/kexin type 9, and 1 in apolipoprotein B). The area under the curve of receiver operating characteristic curve predicting the presence of FH causative mutation by LDL-C level was 0.705, and FH causative mutations were found in all children with LDL-C levels of ≥ 250 mg/dL. Conclusion FH causative mutations were confirmed in almost 60% of the referred children, who were identified through the combination of the lipid universal screening as a part of the health checkup system and the exclusion of secondary hyper-LDL cholesterolemia at the local medical institutions.

Background. Maturity-onset diabetes of the young (MODY) is commonly misdiagnosed as type 1 or type 2 diabetes. Common reasons for misdiagnosis are related to limitations in genetic testing. A precise molecular diagnosis is essential for the optimal treatment of patients and allows for early diagnosis of their asymptomatic family members. Objective. The aim of this study was to identify rare monogenic variants of common MODY genes in Japanese pediatric patients. Methods. We investigated 45 Japanese pediatric patients based on the following clinical criteria: development of diabetes before 17 years of age, a family history of diabetes, testing negative for glutamate decarboxylase-65 (GAD 65) antibodies and insulinoma-2-associated autoantibodies (IA-2A), no significant obesity, and evidence of endogenous insulin production. Genetic screening for MODY1 (HNF4α), MODY2 (GCK), MODY3 (HNF1α), and MODY5 (HNF1β) was performed by direct sequencing followed by multiplex ligation amplification assays. Results. We identified 22 missense variants (3 novel variants) in 27 patients (60.0%) in the GCK, HNF4α, and HNF1α genes. We also detected a whole exon deletion in the HNF1β gene and an exon 5–6 aberration in the GCK gene, each in one proband (4.4%). There were a total of 29 variations (64.4%), giving a relative frequency of 53.3% (24/45) for GCK, 2.2% (1/45) for HNF4α, 6.7% (3/45) for HNF1α, and 2.2% (1/45) for HNF1β genes. Conclusions. Clinicians should consider collecting and assessing detailed clinical information, especially regarding GCK gene variants, in young antibody-negative patients with diabetes. Correct molecular diagnosis of MODY better predicts the clinical course of diabetes and facilitates individualized management.

We investigated serum C-peptide immunoreactivity (CPR) levels in registered data from a multi-center collaborative nationwide type 1 diabetes study. The CPR levels were obtained from 576 and 409 children during the early registration (2013/2014) and late observation (2016/2017) periods, respectively. The percentages of children with a CPR < 0.1 or < 0.3 ng/mL increased according to the duration since diagnosis. Among patients with 5 or more years since diagnosis, 69% had a CPR < 0.1 and 95% had a CPR < 0.3 in the early registration period. A significant negative correlation was observed between the HbA1c and the CPR levels, and the HbA1c levels were significantly higher among children with a CPR < 0.1 or < 0.3 than among those with a CPR ≥ 0.6 ng/mL. During the late observation period, the prevalence of a CPR < 0.1 ng/mL was 88% among long-standing patients and 77% among patients aged 18–20 yr. Regarding the characteristics of “Responders” with a sustained CPR ≥ 0.6 ng/mL at 5 or more years since diagnosis, six of the seven were adolescent females; five of the seven had an HLA DR4-DQ4 haplotype. When type 1A diabetes mellitus (T1AD) children transit to adult care centers, most of them may have some difficulty in glycemic control because of the depleted endogenous insulin.

Aims/Introduction We compared the results of testing for glutamic acid decarboxylase antibodies (GADAb) using a radioimmunoassay (RIA) and an enzyme‐linked immunosorbent assay (ELISA) in individuals with childhood‐onset type 1 diabetes mellitus. Materials and Methods Serum specimens were collected from 1,024 Japanese children (426 boys and 598 girls) in 2013. The median age at diagnosis was 7 years (0–18 years). The blood specimens were obtained at a median age of 13 years (2–22 years). Results Among the 628 children whose serum specimens were collected within 5 years after diagnosis, the rate of GADAb positivity was 47.9% using RIA and 69.4% using ELISA. The participants were divided into four groups according to their RIA and ELISA results for GADAb as follows: group I (RIA+/ELISA+), group II (RIA+/ELISA−), group III (RIA−/ELISA+) and group IV (RIA−/ELISA−). The clinical and genetic characteristics of group I and group III were quite similar in terms of age at diagnosis, male/female ratio, relatively high positive rates for both autoantibody to protein tyrosine phosphatase IA‐2 and autoantibody to the cation efflux transporter zinc transporter 8, and human leukocyte antigen genotype. Group II contained just five patients, and was characterized by a younger age at diagnosis, low positive rates for both autoantibody to protein tyrosine phosphatase IA‐2 and autoantibody to the cation efflux transporter zinc transporter 8, and a unique human leukocyte antigen genotype. If the positive rates of either autoantibody to protein tyrosine phosphatase IA‐2 or autoantibody to the cation efflux transporter zinc transporter 8 or both were added to the GADAb results using RIA, the percentage of autoimmune type 1 diabetes increased from 47.9% to 78.5%. Conclusions The diagnosis of autoimmune childhood‐onset Japanese type 1 diabetes increased when GADAb results were obtained using a new ELISA method, compared with a previously utilized RIA method., The diagnosis of autoimmune childhood‐onset Japanese type 1 diabetes was increased by the glutamic acid decarboxylase antibodies using a new enzyme‐linked immunosorbent assay in comparison with a previous radioimmunoassay.

Background Maturity-onset diabetes of the young (MODY) is commonly misdiagnosed as type 1 or type 2 diabetes. Common reasons for misdiagnosis are related to limitations in genetic testing. A precise molecular diagnosis is essential for the optimal treatment of patients and allows for early diagnosis of their asymptomatic family members. Objective The aim of this study was to identify rare monogenic variants of common MODY genes in Japanese pediatric patients. Methods We investigated 45 Japanese pediatric patients based on the following clinical criteria: development of diabetes before 17 years of age, a family history of diabetes, testing negative for glutamate decarboxylase-65 (GAD 65) antibodies and insulinoma-2-associated autoantibodies (IA-2A), no significant obesity, and evidence of endogenous insulin production. Genetic screening for MODY1 (HNF4α), MODY2 (GCK), MODY3 (HNF1α), and MODY5 (HNF1β) was performed by direct sequencing followed by multiplex ligation amplification assays. Results We identified 22 missense variants (3 novel variants) in 27 patients (60.0%) in the GCK, HNF4α, and HNF1α genes. We also detected a whole exon deletion in the HNF1β gene and an exon 5–6 aberration in the GCK gene, each in one proband (4.4%). There were a total of 29 variations (64.4%), giving a relative frequency of 53.3% (24/45) for GCK, 2.2% (1/45) for HNF4α, 6.7% (3/45) for HNF1α, and 2.2% (1/45) for HNF1β genes. Conclusions Clinicians should consider collecting and assessing detailed clinical information, especially regarding GCK gene variants, in young antibody-negative patients with diabetes. Correct molecular diagnosis of MODY better predicts the clinical course of diabetes and facilitates individualized management.

Introduction: Familial hypercholesterolemia (FH) is an autosomal hereditary disease found in patients who have elevated low-density lipoprotein cholesterol (LDL-C) levels from birth. Early detection and treatment of FH during childhood potentially reduces the risk of premature cardiovascular events. In Kagawa prefecture, a unique community health system, involving three steps, has been conducted to prevent lifestyle-related diseases for 10-year-old children. This system includes universal lipid screening, selection by pediatricians, and next-generation sequencing (NGS) of FH-related genes in the hospitals. The aim of this study is to investigate whether this system can be effective in detection of FH. Methods: In Kagawa prefecture, the universal lipid screening of children at 10 years of age is performed annually at school, covering over 90% of the target group. After excluding secondary hypercholesterolemia, pediatric clinics introduced children with LDL-C levels >140 mg/dL to four hospitals to perform NGS to detect FH. Results: In 2017, 279 children (3.7%) showed elevated LDL-C >140mg/dL among 7,647 ones who received the screening. We performed NGS for 46 children after excluding secondary hypercholesterolemia by pediatricians (LDL-C 186.0±50.3 mg/dL; M/F 27/19) and 26 children (57%) had FH genetic mutations (23 LDL-R, 3 PCSK9). The children with LDL-C >180mg/dL are recommended to receive statin therapy according to the guideline from the Japanese Atherosclerosis Society (JAS). Children with LDL-C levels ≥180 mg/dL have 74% of positive genetic mutations, and even those with 140-180 mg/dl LDL-C levels have as much as 44%, respectively (Table). Conclusions: The unique community health system in Kagawa can efficiently detect FH of children. Further investigation will be required for the effective prevention of future atherosclerotic cardiovascular diseases.

Introduction: Familial hypercholesterolemia (FH) is an autosomal hereditary disease found in patients who have elevated low-density lipoprotein cholesterol (LDL-C) from birth. Early detection and treatment of FH during childhood potentially reduces the risk of premature cardiovascular events. In Kagawa prefecture, a unique community health system, involving three steps, has been conducted to prevent lifestyle-related diseases for 10-year-old children. This system includes universal lipid screening, selection by pediatricians, and next-generation sequencing (NGS) of FH-related genes in hospitals. The aim of this study is to compare 3 international guidelines to detect pediatric FH with this unique community health system in Kagawa. Methods: In Kagawa prefecture, the universal lipid screening of approximately 8,000 children at 10 years of age is performed annually, covering over 90% of the target group. After excluding secondary hypercholesterolemia, pediatric clinics introduced children with LDL-C >140mg/dL to 4 designated hospitals to perform NGS. We applied the guidelines of the Dutch Lipid Clinic Network (DLCN), Simon Broome (SB), and the Japanese Atherosclerosis Society (JAS) to children who received NGS in the unique community health system in Kagawa. Results: We performed NGS for 46 children from January 2018 to February 2020 (LDL-C 186.0±50.3 mg/dL; Male/F 27/19) and 26 (57%) had FH genetic mutations (23 LDL-R and 3 PCSK9 mutations). Seventeen children met FH criteria for DLCN (35%), 10 for Simon Broome (22%), and 11 for JAS (24%), respectively. The combination of NGS and either of the 3 guidelines increased the number of children diagnosed as FH up to 31 (67%). Conclusion: International guidelines detected only half of pediatric FH who were diagnosed by the unique community health system in Kagawa. Further investigation will be required to build an effective universal screening system for pediatric FH.

Amyloid beta peptide (A&beta, )-related studies require an adequate supply of purified A&beta, peptide. However, A&beta, peptides are &ldquo, difficult sequences&rdquo, to synthesize chemically, and low yields are common due to aggregation during purification. Here, we demonstrate an easier synthesis, deprotection, reduction, cleavage, and purification process for A&beta, (1-40) using standard 9-fluorenylmethyloxycarbonyl (Fmoc)-protected amino acids and solid-phase peptide synthesis (SPPS) resin [HMBA (4-hydroxymethyl benzamide) resin] that provides higher yields of A&beta, (1-40) than previous standard protocols. Furthermore, purification requires a similar amount of time as conventional purification processes, although the peptide must be cleaved from the resin immediately prior to purification. The method described herein is not limited to the production of A&beta, (1-40), and can be used to synthesize other easily-oxidized and aggregating sequences. Our proposed methodology will contribute to various fields using &ldquo, difficult sequence&rdquo, peptides, such as pharmaceutical and materials science, as well as research for the diagnosis and treatment of protein/peptide misfolding diseases.

Aims To evaluate comprehensively the use of the glycated albumin to HbA1c ratio for estimation of glycaemic control in the previous month. Methods A total of 306 children with Type 1 diabetes mellitus underwent ≥10 simultaneous measurements of glycated albumin and HbA1c . Correlation and concordance rates were examined between HbA1c measurements taken 1 month apart (ΔHbA1c ) and glycated albumin/HbA1c ratio fluctuations were calculated as Z-scores from the cohort value at enrolment of this study cohort (method A) or the percent difference from the individual mean over time (method B). Results Fluctuations in glycated albumin/HbA1c ratio (using both methods) were weakly but significantly correlated with ΔHbA1c , whereas concordance rates were significant for glycaemic deterioration but not for glycaemic improvement. Concordance rates were higher using method B than method A. Conclusions The glycated albumin/HbA1c ratio was able to estimate glycaemic deterioration in the previous month, while estimation of glycaemic improvement in the preceding month was limited. Because method B provided a better estimate of recent glycaemic control than method A, the individual mean of several measurements of the glycated albumin/HbA1c ratio over time may also identify individuals with high or low haemoglobin glycation phenotypes in a given population, such as Japanese children with Type 1 diabetes, thereby allowing more effective diabetes management.

Background A core sequence (the 9 C-terminal residues) of calcification-associated peptide (CAP- 1) isolated from the exoskeleton of the red swamp crayfish was previously shown to control calcium carbonate precipitation with chitin. In addition, a modified core sequence in which the phosphorylated serine at the N terminus is replaced with serine exhibits was also previously shown to alter precipitation characteristics with chitin. Objectives We focused on calcium carbonate precipitation and attempted to elucidate aspects of the mechanism underlying mineralization. We attempted to evaluate in detail the effects of modifying the N-terminus in the core sequence on calcium carbonate mineralization without chitin. Methods The peptide modifications included phosphorylation, dephosphorylation, and a free or acetylated Nterminus. The peptides were synthesized manually on Wang resin using the DIPCI-DMAP method for the first residue, and Fmoc solid phase peptide synthesis with HBTU-HOBt for the subsequent residues. Prior to calcium carbonate precipitation, calcium carbonate was suspended in MilliQ water. Carbon dioxide gas was bubbled into the stirred suspension, then the remaining solid CaCO3 was removed by filtration. The concentration of calcium ions in the solution was determined by standard titration with ethylenediaminetetraacetate. Calcium carbonate precipitation was conducted in a micro tube for 3 h at 37°C. We used the micro-scale techniques AFM (atomic force microscopy) and TEM (transmission electron microscopy), and the macro-scale techniques chelate titration, HPLC, gel filtration, CD (circular dichroism) and DLS (dynamic light scattering). Results We determined the morphologies of the calcium carbonate deposits using AFM and TEM. The pS peptide provided the best control of the shape and size of the calcium carbonate round particles. The acetylated peptides (Ac-S and Ac-pS) provided bigger particles with various shapes. S peptide provided a mixture of bigger particles and amorphous particles. We verified these findings using DLS. All the peptide samples produced nanostructures of the expected size in agreement with the AFM and TEM results. We estimated the abilities of these peptides to precipitate calcium carbonate by determining the residual calcium hydrogen carbonate concentration by standard titration with ethylenediaminetetraacetate after calcium carbonate precipitation. The Ac-pS peptide showed the lowest residual calcium hydrogen carbonate concentration whereas the S peptide showed the highest, suggesting that the precipitating activities of these peptides towards calcium carbonate correlated with peptide net charge. Then the gel filtration results showed a large oligomer peak and a small oligomer/monomer peak for all peptide samples in agreement with the AFM, TEM and DLS results. CD measurements showed that all the peptides formed random-coil-like structures. Thus, we used both macro- and micro-observation techniques such as chelate titration, DLS, AFM and TEM to show that the calcium carbonate precipitating activities of four derivatives of the core sequence of CAP-1 may correlate with the peptide net charge. Conclusion These peptides mainly act as a catalyst rather than as a binder or component of the calcium carbonate deposits (as a template). On the other hand, the morphologies of the calcium carbonate deposits appeared to be dependent on the ability of the peptide to assemble and act as a template. Consequently, elucidating the relationship between peptide sequence and the ability of the peptide to assemble would be indispensable for controlling precipitate morphologies in the near future. This knowledge would provide important clues for elucidating the relationship between peptide sequence and mineralization ability, including deposit morphology and precipitating activity, for use in nanobiochemistry and materials chemistry research.

Background Mutations in causative genes for neonatal diabetes or maturity-onset diabetes of the young have been identified in multiple patients with autoantibody-negative type 1 diabetes (T1D). Objectives We aimed to clarify the prevalence and phenotypic characteristics of monogenic abnormalities among 89 children with autoantibody-negative insulin-requiring T1D. Methods Mutations in 30 genes were screened using next-generation sequencing, and copy-number alterations of 4 major causative genes were examined using multiplex-ligation-dependent probe amplification. We compared the clinical characteristics between mutation carriers and non-carriers. Results We identified 11 probable pathogenic substitutions (6 in INS , 2 in HNF1A , 2 in HNF4A , and 1 in HNF1B ) in 11 cases, but no copy-number abnormalities. Only 2 mutation carriers had affected parents. De novo occurrence was confirmed for 3 mutations. The non-carrier group, but not the carrier group, was enriched with susceptible HLA alleles. Mutation carriers exhibited comparable phenotypes to those of non-carriers, except for a relatively normal body mass index (BMI) at diagnosis. Conclusions This study demonstrated significant genetic overlap between autoantibody-negative T1D and monogenic diabetes. Mutations in INS and HNF genes, but not those in GCK and other monogenic diabetes genes, likely play critical roles in children with insulin-requiring T1D. This study also suggests the relatively high de novo rates of INS and HNF mutations, and the etiological link between autoimmune abnormalities and T1D in the non-carrier group. Carriers of monogenic mutations show non-specific phenotypes among all T1D cases, although they are more likely to have a normal BMI at diagnosis than non-carriers.

Aims/Introduction Although genome-wide association studies have identified more than 50 susceptibility genes for type 1 diabetes, low-frequency risk variants could remain unrecognized. The present study aimed to identify novel type 1 diabetes susceptibility genes by newly established methods. Materials and Methods We performed whole-exome sequencing and genome-wide copy-number analysis for a Japanese family consisting of two patients with type 1 diabetes and three unaffected relatives. Further mutation screening was carried out for 127 sporadic cases. The functional consequences of identified substitutions were evaluated by in silico analyses and fluorescence-activated cell sorting of blood samples. Results Whole-exome sequencing and genome-wide copy-number analysis of familial cases showed co-segregation of the p.V863L substitution in CD101, the human homolog of an autoimmune diabetes gene in the nonobese diabetic mouse, with type 1 diabetes. Mutation screening of CD101 in 127 sporadic cases detected the p.V678L and p.T944R substitutions in two patients. The p.V863L, p.V678L, and p.T944R substitutions were absent or extremely rare in the general population and were assessed as “probably/possibly damaging” by in silico analyses. CD101 expression on monocytes, granulocytes, and myeloid dendritic cells of mutation-positive patients was weaker than that of control individuals. Conclusions These results raise the possibility that CD101 is a susceptibility gene for type 1 diabetes. This article is protected by copyright. All rights reserved.

KLF11 is the causative gene for maturity-onset diabetes of the young 7 (MODY7). KLF11 regulates insulin gene expression through binding to the GC box in the promoter. To date, only two KLF11 mutations have been identified in three families with early-onset type 2 diabetes. Here, we report a novel KLF11 variant associated with early childhood-onset type 1B diabetes. The proband and his younger sister exhibited hyperglycemia at age 1 year, and their mother developed diabetes at age 4 years. These three individuals required insulin injection from the initial phase of the disease. Being negative for islet cell autoantibodies, they were diagnosed with type 1B diabetes. Mutation screening for 30 diabetes-associated genes identified a heterozygous KLF11 variant (p.His418Gln) in the proband and his sister. The variant was also detected in the affected mother, as well as in the allegedly unaffected maternal grandmother. In silico analyses indicated that this variant involves a highly conserved histidine residue in the first C2 H2 zinc finger domain which ligates a zinc ion. In vitro analyses showed that expression levels and intracellular localization of His418Gln-KLF11 were comparable to those of wildtype (WT)-KLF11. Luciferase assays demonstrated that while WT-KLF11 suppressed the activity of a 6 × GC box-containing reporter, His418Gln-KLF11 lacked the suppressive effect. Notably, His418Gln-KLF11 canceled the suppressive effect of co-transfected WT-KLF11. Such a dominant-negative effect was absent in the previously reported Ala347Ser-KLF11 variant. These results indicate that specific variants of KLF11 (MODY7) with a dominant-negative effect underlie early childhood-onset type 1B diabetes with incomplete penetrance. This study documents a novel monogenic mutation associated with diabetes in children.

Pseudohypoparathyroidism type 1A (PHP1A) is characterized by resistance to multiple hormones, the Albright Hereditary Osteodystrophy phenotype, obesity, and developmental delay. Developmental delay usually appears prior to hypocalcemia due to parathyroid hormone resistance and could be a clinically important feature for early diagnosis of PHP1A. To date, however, the details have not been documented. With regard to developmental delays, we conducted a multicenter retrospective study of 22 PHP1A patients from 18 families who were diagnosed clinically or genetically from 2005 to 2015. For quantitative analysis of their development, we calculated the ratios of the milestone ages of the patients to those in normal reference data. The ratio of the ages with respect to speech development, i.e., speaking a first meaningful word (median: 1.67), was significantly higher than that for gross motor development, walking unassisted (median: 1.34). The ratio of age at stringing a two-word sentence (median: 1.32) was significantly lower than that of saying a first word (median: 1.84). Ten out of 11 (91%) patients exhibited two or three of the following clinical phenotypes: developmental delay, obesity, and hyperthyrotropinemia. These results suggest two possible clinical features of developmental delays in PHP1A patients: developmental delay is more obvious in speech acquisition than in gross motor skills, and speech delays could be attenuated during later childhood. Further, the presence of multiple of three clinical symptoms could be an important indicator to differentiate the diagnosis of PHP1A during early childhood.

Aims The aim of this study was to clarify the significance of previously reported susceptibility variants in the development of autoimmune Type 1 diabetes in non-white children. Tested variants included rs2290400, which has been linked to Type 1 diabetes only in one study on white people. Haplotypes at 17q12-q21 encompassing rs2290400 are known to determine the susceptibility of early-onset asthma by affecting the expression of flanking genes. Methods We genotyped 63 variants in 428 Japanese people with childhood-onset autoimmune Type 1 diabetes and 457 individuals without diabetes. Possible association between variants and age at diabetes onset was examined using age-specific quantitative trait locus analysis and ordered-subset regression analysis. Results Ten variants, including rs2290400 in GSDMB, were more frequent among the people with Type 1 diabetes than those without diabetes. Of these, rs689 in INS and rs231775 in CTLA4 yielded particularly high odds ratios of 5.58 (corrected P value 0.001; 95% CI 2.15–14.47) and 1.64 (corrected P value 5.3 × 10-5; 95% CI 1.34–2.01), respectively. Age-specific effects on diabetes susceptibility were suggested for rs2290400; heterozygosity of the risk alleles was associated with relatively early onset of diabetes, and the allele was linked to the phenotype exclusively in the subgroup of age at onset ≤ 5.0 years. Conclusions The results indicate that rs2290400 in GSDMB and polymorphisms in INS and CTLA4 are associated with the risk of Type 1 diabetes in Japanese children. Importantly, cis-regulatory haplotypes at 17q12-q21 encompassing rs2290400 probably determine the risk of autoimmune Type 1 diabetes predominantly in early childhood.

Methylation defects in the imprinting locus at chromosome 6q24 result in transient neonatal diabetes and small-for-gestational age (SGA) births (1). These phenotypes are primarily ascribed to the overexpression of PLAGL1, a paternally expressed gene on 6q24 that regulates cell cycle and apoptosis (2). Paternal uniparental disomy involving 6q24, as well as copy-number gains of paternal PLAGL1 alleles and epimutations in maternal alleles, have been identified as the causes of hypomethylation at the differentially methylated region (DMR) of PLAGL1 (3, 4). Recently, Yorifuji et al. reported the identification of 6q24 uniparental disomy in three patients with childhood-onset non-autoimmune diabetes mellitus (5). The three patients were identified through methylation-specific PCR analysis of the PLAGL1 DMR of 113 patients clinically suspected of having maturity-onset diabetes of the young (MODY). These results expanded the phenotypic consequences of 6q24 methylation defects to include MODY-like manifestations without a history of neonatal diabetes. However, the frequency of 6q24 methylation defects among patients with childhood-onset non-autoimmune diabetes remained unknown.

AIM To examine the contribution of PTPN2 coding variants to the risk of childhood-onset Type 1A diabetes. METHODS PTPN2 mutation analysis was carried out for 169 unrelated Japanese people with childhood-onset Type 1A diabetes. We searched for coding variants that were absent or extremely rare in the general population and were scored as damaging by multiple in silico programs. We performed mRNA analysis and three-dimensional structural prediction of the detected variants, when possible. We also examined possible physical links between these variants and previously reported risk SNPs as well as clinical information from variant-positive children. RESULTS One frameshift variant (p.Q286Yfs*24) and two probably damaging missense substitutions (p.C232W and p.R350Q) were identified in one child each. Of these, p.Q286Yfs*24 and p.C232W were hitherto unreported, while p.R350Q accounted for 2/121,122 alleles of the exome datasets. The p.Q286Yfs*24 variant did not encode stable mRNA, and p.C232W appeared to affect the structure of the tyrosine-protein phosphatase domain. The three variants were physically unrelated to known risk SNPs. The variant-positive children manifested Type 1A diabetes without additional clinical features and invariably carried risk human leukocyte antigen alleles. CONCLUSIONS The results provide the first indication that PTPN2 variants contribute to the risk of Type 1A diabetes, independently of known risk SNPs. PTPN2 coding variants possibly induce non-specific Type 1A diabetes phenotypes in individuals with human leukocyte antigen-mediated disease susceptibility. Our findings warrant further validation.

Non-classical 21-hydroxylase deficiency (NC21-OHD) is a mild form of 21-hydroxylase deficiency lacking apparent symptoms of androgen excess at birth. Most NC21-OHD cases are diagnosed after the onset of puberty, while a substantial number of patients are not diagnosed during childhood. Previous studies have reported ethnic differences in the prevalence of NC21-OHD. To date, the clinical features of NC21-OHD in Japanese children have not been systemically reported. Thus, we performed 3 independent analyses: retrospective analyses of newborn screening in 2 major Japanese cities (Sapporo and Niigata) and a national surveillance collecting clinical information from pediatric endocrinologists throughout the country. During the last 10 years, one case of NC21-OHD was diagnosed by newborn screening in each city, resulting in incidences of 2.0 (95% confidence interval = 0.0-5.9) and 2.1 (0.0-6.2) per 1,000,000 in Sapporo and Niigata, respectively. We collected information from 85% of the 135 Councilors of Japanese Society of Pediatric Endocrinology. Fifteen NC21-OHD patients were diagnosed during childhood, resulting in the estimated prevalence of 0.58 (0.28-1.1) per 1,000,000. Eleven patients were discovered by newborn screening, 7 patients developed hyperandrogenism symptoms (2-8 years of age, median 7), and 9 patients were treated with hydrocortisone at the time of the survey. Ten out of 13 patients showed compound heterozygosity for the P30L mutation of CYP21A2. Our study suggests that the prevalence/incidence of NC21-OHD is lower than that in Western countries, and that the age for initial onset of androgen excess symptoms varies during the prepubertal period.

Mandibular hypoplasia, deafness, progeroid features and lipodystrophy (MDPL) syndrome is a rare autosomal dominant disorder caused by heterozygous POLD1 mutations. To date, 13 patients affected by POLD1 mutation-caused MDPL have been described. We report a clinically undiagnosed 11-year-old male who noted joint contractures at 6 years of age. Targeted exome sequencing identified a known POLD1 mutation [NM_002691.3:c.1812_1814del, p.(Ser605del)] that diagnosed him as the first Japanese/East Asian MDPL case.

Permanent neonatal diabetes mellitus (PNDM) is a rare form of insulin-dependent diabetes mellitus that presents within the first 6 months after birth and may require lifelong insulin treatment. Approximately 40% of all PNDM cases are caused by activating mutations in either the KCNJ11 gene or ABCC8 gene, which encode the Kir6.2 or sulfonylurea receptor (SUR) 1 subunit of the ATP-sensitive potassium channel (KATP channel), respectively (1,2,3). The KATP channel is expressed on the surface of pancreatic beta cells. In this context, a heterozygous gain-of-function mutation in ABCC8 or KCNJ11 causes PNDM. High-dose oral sulfonylurea has been reported to be an effective treatment agent for PNDM with ABCC8 and KCNJ11 gene mutations compared with insulin injection (4). Here we report a patient with PNDM caused by a novel heterozygous missense mutation in ABCC8 and controlled with oral glibenclamide for more than 3 yr.

Monogenic mutations, such as those in the potassium inwardly-rectifying channel, subfamily J, member 11 (KCNJ11) and insulin (INS) genes, are identified in young patients with type 1B diabetes (non-autoimmune-mediated). We recently reported the results of a test for monogenic forms of diabetes in Japanese children who were diagnosed with type 1B diabetes at5 years of age. In this study, we tested for monogenic forms of diabetes in Japanese children aged5 to ≤15.1 years at the diagnosis of type 1B diabetes.Thirty-two Japanese children (eight males, 24 females) with type 1 diabetes negative for glutamate decarboxylase (GAD) 65 and/or IA-2A autoantibodies and who were aged5 to 15.1 years at diagnosis were recruited from 16 independent hospitals participating in the Japanese Study Group of Insulin Therapy for Childhood and Adolescent Diabetes (JSGIT). We performed mutational analyses of genes with a high frequency of mutation [INS, KCNJ11, hepatocyte nuclear factor 1 alpha (HNF1α) and hepatocyte nuclear factor 4 alpha (HNF4α)].We identified one missense mutation (G32S) in the INS gene and two mutations (R131Q and R203S) in the HNF1α gene that could be associated with diabetes. No missense change was found in the KCNJ11 gene.Our results suggest that although mutations in the INS gene can be detected in Japanese patients aged5 years at diagnosis, the frequency of mutations decrease in older age groups. Conversely, the frequency of the mutation in the HNF1α gene increased in patients diagnosed at age 5 or older. Clinicians should consider the possibility of maturity onset diabetes of the young (MODY) in children diagnosed with type 1B diabetes.

We investigated features and responses to treatment in patients with febrile and afebrile convulsions with mild gastroenteritis and characterized convulsions with rotavirus and norovirus gastroenteritis.We conducted a prospective, observational study to evaluate patients with febrile and afebrile convulsions with mild gastroenteritis who were hospitalized between November 2011 and March 2014 at 13 facilities in the National Hospital Organization. We classified the patients into two groups: presence or absence of fever. We investigated the background, clinical and laboratory characteristics, viral antigen in stool, and efficacy of anticonvulsant drugs.Of 126 patients enrolled in this study, 50 were febrile (Fc group) and 76 were afebrile (aFc group). A family history of febrile seizures was significantly more frequent in the Fc group than in the aFc group (28.0% vs 9.2%, P = 0.005). Clinical characteristics were similar between the rotavirus and norovirus groups, but fever was significantly more frequent in the rotavirus group (46.2% vs 8.3%, P 0.001). Serum sodium levels were significantly negatively related to the number of seizures in the aFc group (β = -0.13; 95% confidence interval, -0.24, -0.03; P = 0.01). Carbamazepine was significantly more efficacious than diazepam suppositories in the aFc group (odds ratio = 49.3, 95% confidence interval, 2.35, 1037; P = 0.01).Febrile convulsions with mild gastroenteritis show characteristics of both febrile seizures and convulsions with mild gastroenteritis. Carbamazepine is optimal for convulsions with mild gastroenteritis. Clinical features of convulsions with rotavirus and norovirus gastroenteritis are similar, except for fever. Serum sodium levels may play a major role in the onset of convulsions with mild gastroenteritis.

Phototherapy of a jaundiced neonate is usually started when bilirubin exceeds a threshold in the standard. There are several standards used in the developed countries even though the guideline of American Academy of Pediatrics is considered to be a global standard. Although the purpose of phototherapy is the prevention of kernicterus, nowadays the prevalence of kernicterus in otherwise healthy term neonates in the developed countries is rare. Meanwhile several potential adverse effects of phototherapy have been reported. In the present study we tried to estimate how different the rate of phototherapy for the jaundice of neonates at lower risk of kernicterus would be by different standards. For this purpose, we utilized the records of plasma total bilirubin (TB) values of 1893 healthy neonates of 38 weeks and more which were measured on day 6 for the percentile analysis. However, this database did not include the TB values of the neonates who received phototherapy by day 6. Then the database was corrected with an assumption that TB on day 6 would have been normally distributed if no phototherapy had been performed. The mean and the standard deviation (SD) of corrected database were 11.29 mg/dl (193 μmol/l) and 3.63 mg/dl (62 μmol/l), respectively. Using a standard distribution with these mean and SD, the percents of TB values which exceed 18.0, 19.0, 20.0 and 21.0 mg/dl on day 6 were estimated 3.22%, 1.70%, 0.82% and 0.35%, respectively. Results of the present report would help to estimate the relative rate of phototherapy that is performed for the neonates who are term and otherwise healthy by different standards.

Sugihara S, Ogata T, Kawamura T, Urakami T, Takemoto K, Kikuchi N, Takubo N, Tsubouchi K, Horikawa R, Kobayashi K, Kasahara Y, Kikuchi T, Koike A, Mochizuki T, Minamitani K, Takaya R, Mochizuki H, Nishii A, Yokota I, Kizaki Z, Mori T, Shimura N, Mukai T, Matsuura N, Fujisawa T, Ihara K, Kosaka K, Kizu R, Takahashi T, Matsuo S, Hanaki K, Igarashi Y, Sasaki G, Soneda S, Teno S, Kanzaki S, Saji H, Tokunaga K, Amemiya S, and The Japanese Study Group of Insulin Therapy for Childhood and Adolescent Diabetes (JSGIT). HLA-class II and class I genotypes among Japanese children with Type 1A diabetes and their families. Objective: To determine the HLA-DRB1, DQB1, DPB1, A, C, and B genotypes among Japanese children with autoimmune type 1 diabetes. Methods: Four hundred and thirty patients who were GADAb and/or IA-2Ab-positive (Type 1A) were recruited from 37 medical centers as part of a nationwide multicenter collaborative study. DNA samples from 83 siblings of the children with Type 1A diabetes and 149 parent–child trios were also analyzed. A case-control study and a transmission disequilibrium test (TDT) were then performed. Results: The susceptible and protective DRB1 and DQB1 alleles and haplotypes were confirmed. DPB1 alleles unique to the Japanese population and those common to multiple ethnic groups were also present. A linkage disequilibrium (LD) analysis showed both susceptible and protective haplotypes. The TDT did not reveal any alleles that were transmitted preferentially from the mother or father to children with Type 1A. Homozygosity for DRB1∗09:01-DQB1∗03:03 and heterozygosity for DRB1∗04:05-DQB1∗04:01 and DRB1∗08:02-DQB1∗03:02 were associated with an extremely high risk of Type 1A. A comparison of children with Type 1A and their parents and siblings suggested a dose effect of susceptible DRB1-DQB1 haplotypes and an effect of protective alleles on immunological pathogenesis. DRB1∗09:01 appeared to be strongly associated with an early onset in preschool children with Type 1A diabetes. Conclusions: This study demonstrated the characteristic association of HLA-class II and class I genes with Type 1A diabetes among Japanese children. A TDT did not reveal the genomic imprinting of HLA-class II and class I genes in Type 1A diabetes.

栃木県産マツタケの子実体から分離した菌株(F275)をHY培地へ移植し, 23℃で暗培養した. F275の培養菌糸をオオムギ培地へ移植して, 40～50日後に種菌を作製することができた. これがマツタケ菌であることはITS領域のシーケンスおよびマツタケ特異的プライマーを用いたPCRによって確認した. 試験管内に調製した素ジェランガム培地で発芽したアカマツ実生に4～5粒のオオムギ種菌を接種し, 培養9ヶ月後のアカマツ実生の側根を微分干渉顕微鏡で観察した結果, マツタケ菌が根の細胞間隙に侵入して菌根を合成した.

We examined children who were diagnosed with asymptomatic type 2 diabetes by school medical examinations to investigate the existence of glucokinase (GCK) gene defects in this group. Among 20 children diagnosed with asymptomatic type 2 diabetes by school medical examinations between 2003 and 2009 at our 2 hospitals, 8 were classified as non-obese type. Among them, we screened 5 children (2 boys and 3 girls; age: 8-13 years) who had mild elevation of fasting plasma glucose (108-134 mg/dL) with slightly high internationally standardized HbA1c levels (6.3-6.9%) at first close examination. Written informed consent was obtained and all families agreed to participate in this study. We found 4 different mutations (G223S, G81C, S336X and T228M) in 4 of the examined children. The blood glucose control levels had not become worse in any children during the 2-6 years follow-up period. The inheritance of diabetes with GCK gene defect was later confirmed in 1 family. These results suggest that GCK gene defects exist in non-obese children who are diagnosed with asymptomatic diabetes by school medical examinations. Cases of diabetes that are caused by GCK mutations may not be as rare in Japanese subjects as previously described and could be found in patients tentatively diagnosed as type 2 diabetes.

To clarify the contribution of Cblb to the development of type1 diabetes (T1D), we investigated Japanese younger-onset T1D patients. We sequenced the cblb gene in 10 T1D patients and screened the identified mutations in 109 Japanese T1D patients and 100 normal subjects. In addition to four previously reported synonymous single nucleotide polymorphisms (SNPs), we identified two novel nonsynonymous variants (786 C>T (A155V) and 1718 A>G (N466D)). The A155V mutation was found in one subject with Basedow's disease whose mother also carried both the mutation and Basedow's disease. The N466D mutation was found in 6 T1D cases including a subject who was classified as fulminant T1D. We found no significant differences in the allele frequency of these SNPs among T1D and control subjects, suggesting that the contribution of cblb to the genetic susceptibility to T1D might not be high for Japanese younger-onset T1D.

A 65-year-old woman experienced progressive intrinsic muscle wasting on the right hand over a period of 7 years. The distribution of muscular atrophy and weakness was consistent with the area innervated by the right C8 and Th1 nerve roots. Neurophysiological examination suggested a right lower trunk lesion. An elongated right transverse process of the C7 vertebra and an aberrant subclavian artery were detected on computed tomography images, and the right lower trunk of the brachial plexus appeared to be lifted upward on magnetic resonance images. The patient was diagnosed with true neurogenic thoracic outlet syndrome. A fibrous band extending from the elongated transverse process was found during surgery, and symptoms did not progress further after resection of the band. True neurogenic thoracic outlet syndrome can cause monomelic amyotrophy, and localized neuroimaging and detailed neurophysiological examination were useful for diagnosis.

Gitelman syndrome (GS) is a renal tubular disorder characterized by hypokalemia, hypomagnesemia, metabolic alkalosis and hypocalciuria due to defective tubular reabsorption of magnesium and potassium. This disease is caused by mutations of the thiazide-sensitive Na-Cl cotransporter (NCCT) gene, SLC12A3. Manifestations of GS are heterogeneous, from asymptomatic to mild symptoms of cramps and easy fatigue, to tetany and paralysis. Polydipsia, polyuria, and nocturia are also frequent in GS patients. Here we describe two Japanese patients with GS followed as nocturnal enuresis. In the first patient, occasional muscle cramps, easy fatigue and headache led to the diagnosis of GS. The parents of this patient reported that he had been affected by polydipsia and polyuria, especially nocturnal enuresis from early childhood. The second patient was referred to our clinic because of muscular weakness and cramps. He had a past history of transient muscle weakness and muscle cramps. He had also suffered from nocturnal enuresis since 3 yr of age. Laboratory findings of these patients were consistent with those of GS. Sequencing analysis of the SLC12A3 gene from two patients showed four mutations, which were previously reported. In our two patients, their manifestations had been underestimated and the correct diagnosis was delayed. GS is generally likely to be benign, however signs of GS are found in early childhood. Especially, we must recognize that nocturnal enuresis is frequent in symptoms of GS.

We investigated the changes of anthropometrical parameters in Japanese children with type 1 diabetes (T1DM) from birth to the onset of diabetes. One-hundred ninety-nine children (79 males and 120 females) diagnosed between 0–16 yr of age during the period between 1990 and 2003 were the subjects of this study. The subjects were categorized into 3 groups according to onset age (0–5 yr; n=74, 5–10 yr; n=61, 10–16 yr; n=64). At birth, the younger onset (

We have fabricated a refined copper wiring pattern with a super-connect level on insulating low-k resin, and embedded it in the same insulating resin. We made it by means of a semi-additive process, which enables a flat connection between the copper pattern and the insulating resin. The surface of the copper pattern was processed with a black-oxide treatment (adhesion-promoting copper surface treatment) . The sample was prepared both with and without “A” treatment. The aim of“A”treatment is improvement of the bonding strength between the resins. This paper aims to evaluate the ionic migration durability of the newly developed sample under high temperature and high humidity conditions. We investigated the influence of the treatment that fosters ionic migration, and adopted a mainly AC-impedance method for the analysis of the ionic migration. The impedance analysis gave the initial information for the ionic migration. This analysis method could be used for the estimation of forthcoming ionic migrations.

Application of cosmogenic radionuclide 22 Na to limnological research was first successfully performed in the Lake Biwa system, Japan. The 22 Na was determined from large water samples of more than 500 L by using the ultra low-background Ge-detector installed at underground (Ogoya Lab.) after simple chemical separation. Extremely low 22 Na concentrations ranging from 19.9 to 32.7 mBq/m 3 and from 27.4 to 38.3 mBq/m 3 were found in the lake and river water samples, respectively. Mass balances of 22 Na from the watershed to river and lake were constructed by considering the atmospheric deposition of 22 Na. The mean residence times of 22 Na in the southern and northern basins of Lake Biwa were estimated as about 18 days and 5.4 years, respectively. Furthermore, the mean residence time of this atmospheric nuclide in the watershed was evaluated as about 7.3 years, whose value may be helpful in tracing the fate of contaminants with similar chemical properties in the watershed. The quantity of groundwater flow into the lake was also roughly estimated to be 1.6×10 9 m 3 /yr from the specific activity of 22 Na/Na.

The aim of this study was to evaluate the past 10-year status of insulin therapy for preschool-age children with type 1 diabetes in Japan. One-hundred and forty-two patients who had been diagnosed at less than 5 years of age within the past 10 years (1993–2002) at 36 hospitals were registered in this study on April 2003. The methods of daily insulin therapy and episodes of severe hypoglycemia during the preschool period were investigated. Eighty-six (60.6%) children were treated with a pen-type device and 56 (39.4%) were treated with a syringe-type device. The once-a-day insulin regimen was used for 2, a twice-a-day regimen for 104, a three-times-a-day for 28 and a four-times-a-day for 8. Episodes of severe hypoglycemia were recorded in nearly half of the subjects, and one-fourth of the subjects had repeated episodes. One hundred and eleven of their parents were questioned regarding the degree of psychosocial stress experienced during the care of their children. Most parents worried about the glycosylated hemoglobin value at each hospital visit. They were next very afraid of nocturnal severe hypoglycemia, independent of any actual experience. These results suggest that although insulin therapy can involve various methods, the important point is to simultaneously provide good glycemic control and prevent severe hypoglycemia, especially during this age.

OBJECTIVE: The aim of this study was to examine plasma adiponectin concentrations during perinatal the period and their correlations with fetal anthropometric parameters and other hormones. DESIGN: Venous cord blood samples were obtained from 59 full-term healthy newborns (36 males and 23 females, gestational age 37.0-41.4 weeks, birth weight 2,146-4,326 g, birth length 44.0-54.5 cm). The blood samples were also obtained from 15 neonates (postnatal day 3-7) whose cord blood had already been collected and the changes in adiponectin concentrations were examined. MEASUREMENTS: The adiponectin concentration was determined by enzyme-linked immunosorbent assay. The leptin concentration was determined by radioimmunoassay. Insulin, GH and IGF-1 concentrations were determined by immunoradiometric assays. RESULTS: The plasma adiponectin concentrations in cord blood ranged from 6.0 to 55.8 microg/ml (median 22.4 microg/ml), which were much higher than those in normal-weight adults (P < 0.0001). In contrast to the findings in adults, these values were positively correlated with birth weight (r = 0.43, P = 0.0005), body mass index (r = 0.44, P = 0.0005), birth weight/birth length ratio (r = 0.46, P = 0.0002) and the leptin concentrations (r = 0.39, P = 0.004). When the effects of fat mass-related anthropometric parameters such as the birth weight/birth length ratio were controlled, plasma adiponectin concentrations had a significant inverse correlation with insulin concentrations (r = -0.35, P = 0.01). There was no significant gender difference in adiponectin concentrations among newborns. The adiponectin concentrations in neonates (postnatal day 3-7) did not change significantly compared with those in cord blood. CONCLUSIONS: In contrast to the findings in adults, these results suggest that the adiponectin concentration increases with the mass of fetal fat.

The twitcher mouse is well known as a naturally occurring authentic mouse model of human globoid cell leukodystrophy (GLD; Krabbe disease) due to genetic deficiency of lysosomal galactosylceramidase. The twitcher mice used most commonly are on the C57BL/6J background. We generated twitcher mice that were on the mixed background of C57BL/6J and 129SvEv, the standard strain for production of targeted mutations. Twitcher mice on the mixed background were smaller and had a shorter lifespan than were those on the C57BL/6J background. Many twitcher mice on the mixed background developed generalized seizures around 30 days that were never seen in twitcher mice on the C57BL/6J background. Neuropathologically, although the degree of the typical demyelination with infiltration of macrophages was similar in the central and peripheral nervous systems, in both strains, marked neuronal cell death was observed only in twitcher mice on the mixed background. In the hippocampus, the neuronal cell death occurred prominently in the CA3 region in contrast to the relatively well-preserved CA1 and CA2 areas. This neuropathology has never been seen in twitcher mice on the C57BL/6J background. Biochemically, the brain of twitcher mice on the mixed background showed much greater accumulation of lactosylceramide. Genetic background must be carefully taken into consideration when phenotype of mutant mice is evaluated, particularly because most targeted mutants are initially on a mixed genetic background and gradually moved to a pure background. These findings also suggest an intriguing possibility of important function of some sphingolipids in the hippocampal neuronal organization and maintenance.

The changes in the leptin and ghrelin concentrations during the perinatal period are reviewed and their possible roles are discussed. In humans, leptin concentrations in cord blood were positively correlated with the birth weight and Kaup index. Most leptin was derived from fetal adipocytes, although the placenta has also been shown to make a contribution. An apparent gender difference in these concentrations (male

Pyruvate dehydrogenase complex (PDHC) deficiency is a major cause of congenital lactic acidemia in children. PDHC catalyzes the thiamine-dependent decarboxylation of pyruvate. Thiamine treatment was effective for some patients with PDHC deficiency. We reexamined 30 patients with congenital lactic acidemia of unknown origin who had normal PDHC activity in their cultured fibroblasts using a routine assay with a high (0.4 mM) thiamine pyrophosphate (TPP) concentration. We measured the activity of PDHC in the presence of a low (1x10(-4) mM) TPP concentration, and analyzed for mutations in the E1alpha subunit gene. Three males had low PDHC activity in the presence of 1x10(-4) mM TPP. The DNA sequence of these three patients' X-linked E1alpha subunit revealed a substitution of alanine for valine at position 71 (V71A) in exon 3, phenylalanine for cysteine at position 101 (C101F) in exon 4, and glycine for arginine at position 263 (R263G) in exon 8, respectively. Thiamine treatment was effective in these three patients. Therefore, they had a thiamine-responsive PDHC deficiency due to a point mutation in the E1alpha subunit gene. PDHC activity should be measured at a low TPP concentration to detect thiamine-responsive PDHC deficiency so that thiamine treatment can be initiated as soon as possible.

Leigh syndrome, a severe neurodegenerative disorder, commonly is associated with cytochrome c oxidase deficiency. Recent studies in white patients indicate that SURF-1 gene mutations can cause Leigh syndrome associated with cytochrome c oxidase deficiency. When we measured cytochrome c oxidase activity in cultured lymphoblastoid cells from our Japanese patients with typical Leigh syndrome, three patients demonstrated cytochrome c oxidase deficiency. Three novel mutations of the SURF-1 gene were identified in two of these three patients with cytochrome c oxidase deficiency. All mutations predicted loss of function of the SURF-1 protein; in both patients' cells, cytochrome c oxidase activity was decreased to less than 20% of the control mean. These results indicate that cultured lymphoblastoid cells are useful for elucidating the etiology of Leigh syndrome, and that loss of function of the SURF-1 gene product can be responsible for Leigh syndrome associated with severe cytochrome c oxidase deficiency in Japanese patients.