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Background POU1F1 encodes both PIT-1α, which plays pivotal roles in pituitary development and GH, PRL and TSHB expression, and the alternatively spliced isoform PIT-1β, which contains an insertion of 26-amino acids (β-domain) in the transactivation domain of PIT-1α due to the use of an alternative splice acceptor at the end of the first intron. PIT-1β is expressed at much lower levels than PIT-1α and represses endogenous PIT-1α transcriptional activity. Although POU1F1 mutations lead to combined pituitary hormone deficiency (CPHD), no patients with β-domain mutations have been reported. Results Here, we report that a three-generation family exhibited different degrees of CPHD, including growth hormone deficiency with intrafamilial variability of prolactin/TSH insufficiency and unexpected prolactinoma occurrence. The CPHD was due to a novel POU1F1 heterozygous variant (c.143-69T>G) in intron 1 of PIT-1α (RefSeq number NM_000306) or as c.152T>G (p.Ile51Ser) in exon 2 of PIT-1β (NM_001122757). Gene splicing experiments showed that this mutation yielded the PIT-1β transcript without other transcripts. The lymphocyte PIT-1β mRNA expression was significantly higher in the patients with the heterozygous mutation than a control. A luciferase reporter assay revealed that the PIT-1β-Ile51Ser mutant repressed PIT-1α and abolished transactivation capacity for the rat prolactin promoter in GH3 pituitary cells. Conclusions We describe, for the first time, that the PIT-1β mutation can cause CPHD through a novel genetic mechanism, such as PIT-1β overexpression, and that POU1F1 mutation might be associated with a prolactinoma. Analysis of new patients and long-term follow-up are needed to clarify the characteristics of PIT-1β mutations.

Wolfram syndrome (WS) is a monogenic diabetes caused by variants of the WFS1 gene. It is characterized by diabetes mellitus (DM) and optic atrophy (OA). Individuals with WS initially present with autoantibody-negative type 1 DM (T1BDM). The diagnosis is often delayed or misdiagnosed even after visual impairment becomes apparent. We report a case of WS diagnosed by ophthalmologic screening before the appearance of visual impairment. A 7-year-old male patient developed T1BDM at the age of 3 years. At 6 years of age, his endogenous insulin secretion decreased but was not completely depleted, and glycemic control was good with insulin treatment. Fundus examination at that time revealed optic nerve head pallor, and WFS1 gene analysis confirmed a compound heterozygous variant (c.2483delinsGGA/c.1247TA). Ophthalmologic screening can help in early diagnosis of WS in T1BDM especially when if endogenous insulin secretion is preserved, which would facilitate effective treatment.

The development of pneumococcal conjugate vaccines has substantially decreased the incidence of invasive pneumococcal diseases. However, the incidence of bacteremia due to nonvaccine serotypes has increased. Therefore, it is important to recognize the symptoms and complications of pneumococcal infection to expedite diagnosis. Herein, we report the case of a 22-month-old patient diagnosed with pneumococcal bacteremia who presented with cholestatic jaundice and fever without any other signs of systemic sepsis. The patient's condition improved soon after antibacterial therapy. Other causes of jaundice were possibly ruled out based on the screening test for viral hepatitis, and there were no abnormal findings on abdominal ultrasonography. Therefore, the present case suggests that cholestatic jaundice could be a manifestation of pneumococcal bacteremia.

Congenital adrenal hyperplasia is a category of disorders characterized by impaired adrenocortical steroidogenesis. The most frequent disorder of congenital adrenal hyperplasia is 21-hydroxylase deficiency, which is caused by pathogenic variants of

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.

The appropriate antimicrobial treatment period for febrile urinary tract infection (UTI) can be changed, depending on whether the patient has acute focal bacterial nephritis (AFBN). The aim of this study was to clarify the characteristics of AFBN compared with those of acute pyelonephritis (APN) and establish a strategy to detect AFBN.A total of 77 patients diagnosed with febrile UTI were enrolled. They were divided into APN (n = 64) and AFBN groups (n = 13). The clinical data and other laboratory biomarkers were retrospectively analyzed.The time required for fever resolution after antimicrobial treatment was significantly longer in the AFBN group than in the APN group (2.77 days vs 1.11 days, respectively, P0.001). Also, the time to disappearance of pyuria after antimicrobial treatment was longer in the AFBN group than in the APN group (6.22 days vs 2.32 days, respectively, P = 0.001). Fever lasting1.75 days after antimicrobial treatment had a sensitivity of 92% and specificity of 79% for the detection of AFBN, while pyuria disappearance after 4 days had a sensitivity of 88% and specificity of 85%. When patients fulfilled both cut-offs, the sensitivity and specificity were 89% and 97%.Acute focal bacterial nephritis was associated with fever of significantly longer duration after antimicrobial treatment, and it took a longer time for pyuria to disappear. Children with febrile UTI should be evaluated for AFBN if the fever persists ≥48 h after the initiation of antimicrobial treatment and if pyuria lasts for 4 days.

Biallelic neuroblastoma amplified sequence (NBAS) gene mutations have recently been identified to cause a reduction in its protein expression and a broad phenotypic spectrum, from isolated short stature, optic nerve atrophy, and Pelger-Huet anomaly (SOPH) syndrome or infantile liver failure syndrome 2 to a combined, multi-systemic disease including skeletal dysplasia and immunological and neurological abnormalities. Herein, we report a 34-year-old patient with a range of phenotypes for NBAS deficiency due to compound heterozygous variants; one is a SOPH-specific variant, p.Arg1914His, and the other is a novel splice site variant, c.6433-2A>G. The patient experienced recurrent acute liver failure until early childhood. Hypogammaglobulinemia, a decrease in natural killer cells, and optic nerve atrophy were evident from infancy to childhood. In adulthood, the patient exhibited novel phenotypic features such as hepatic cirrhosis complicated by portal hypertension and autoimmune hemolytic anemia. The patient also suffered from childhood-onset insulin-requiring diabetes with progressive beta cell dysfunction. The patient had severe short stature and exhibited dysmorphic features compatible with SOPH, intellectual disability, and epilepsy. NBAS protein expression in the patient's fibroblasts was severely low. RNA expression analysis for the c.6433-2A>G variant showed that this variant activated two cryptic splice sites in intron 49 and exon 50, for which the predicted consequences at the protein level were an in-frame deletion/insertion, p.(Ile2199_Asn2202delins16), and a premature termination codon, p.(Ile2199Tyrfs*17), respectively. These findings indicate that NBAS deficiency is a multi-systemic progressive disease. The results of this study extend the spectrum of clinical and genetic findings related to NBAS deficiency.

Context Lipoid congenital adrenal hyperplasia (LCAH) is caused by mutations in STAR. Classic (CLCAH) and nonclassic (NCLCAH) forms were reported as total and partial deficiencies, respectively, of adrenal and gonadal steroid hormones. The rarity of LCAH has precluded large-scale epidemiological and clinical investigations. Objective To determine the epidemiological and clinical characteristics of 2 forms of LCAH. Design A multicenter cross-sectional cohort study in Japan on December 1, 2017. Participants Fifty-seven patients with LCAH (median age, 23.7 years; range, 0.0–47.5 years). Main Outcome Measures Patient demographics, STAR genotype, Quigley grade, endocrinological and imaging data, treatment, and prognosis. Results Fifty-three and 4 patients fulfilled definite and probable diagnostic criteria for LCAH, respectively. When NCLCAH was defined as either Quigley grade 1 in XY karyotype, no episode of salt losing or requirement of fludrocortisone, or onset of primary adrenal insufficiency (PAI) at 1 year or older, patients were divided into groups of 43 patients with CLCAH (75.4%), 11 with NCLCAH (19.3%), and 3 with unclassified LCAH (5.3%). All of the patients with CLCAH and 7/11 NCLCAH (63.6%) were treated with fludrocortisone. CLCAH was diagnosed at a significantly younger age than NCLCAH (median, 0.0 vs 4.0 years). STAR-Arg272Cys or -Met225Thr was identified only in NCLCAH (8/11, 72.7%). Conclusions We demonstrated the relative proportions and clinical and molecular characteristics of NCLCAH and CLCAH in Japan. These criteria for NCLCAH correspond to all previously published cases and our cases whose masculinization of the external genitalia, ability of mineralocorticoid production, and onset of PAI were described.

Maternal–fetal calcium (Ca2+) transport in the placenta plays a critical role in maintaining fetal bone mineralization. Mutations in the gene encoding the transient receptor potential cation channel, subfamily V, member 6 (TRPV6) have been identified as causative mutations of transient neonatal hyperparathyroidism due to insufficient maternal–fetal Ca2+ transport in the placenta. In this study, we found two novel mutations in subjects that have transient neonatal hyperparathyroidism. TRPV6 carrying the mutation p.Arg390His that localizes to the outer edge of the first transmembrane domain (S1) showed impaired trafficking to the plasma membrane, whereas TRPV6 having the mutation p.Gly291Ser in the sixth ankyrin repeat (AR) domain had channel properties that were comparable those of WT channels, although the increases in steady-state intracellular Ca2+ concentration could have led to Ca2+ overload and subsequent death of cells expressing this mutant channel. These results indicate that the AR6 domain contributes to TRPV6-mediated maintenance of intracellular Ca2+ concentrations, and that this region could play a novel role in regulating the activity of TRPV6 Ca2+-selective channels.

A 14-year-old girl was referred to our department because of headache and visual impairment following the resection of recurrent cardiac myxoma. Head magnetic resonance imaging (MRI) scan detected an intra- and supra-sellar tumor. Moreover, the patient showed the presence of spotty skin pigmentations on her cheeks and lower lip. Blood examination revealed hypothyrotropinemia, and ultrasonography results revealed multiple thyroid nodules. She was diagnosed with Carney complex (CNC). Her pituitary tumor was suspected as growth hormone (GH)-secreting adenoma, because overgrowth was observed in the patient. However, biochemical examinations, including oral glucose tolerance test, failed to show the characteristic findings of GH-secreting adenoma. In contrast, insulin tolerance test showed GH deficiency. Her visual impairment improved without performing decompression surgery, and the tumor size decreased, as per the MRI findings. Based on clinical course, the patient was diagnosed with pituitary apoplexy in pituitary adenoma, following which she was discharged. At 3 months after discharge, thyrotropin-releasing hormone loading test performed revealed low thyrotropin-stimulating hormone and thyroid hormone levels, and the patient was in a depressed mood. Therefore, l-T4 replacement was initiated, following which her GH secretory capacity gradually improved. Here, we report, to the best of our knowledge, the first case of a patient with pituitary apoplexy in CNC. Such condition must be identified in young patients with recurrent cardiac myxoma, and examinations, such as head MRI, must be performed.

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.

In search for clues towards the understanding of the cold plasma sheet formation under northward IMF, we study the temperature anisotropy of the two-component protons in the plasma sheet near the dusk low-latitude boundary observed by the Geotail spacecraft. The two-component protons result from mixing of the cold component from the solar wind and the hot component of the magnetospheric origin, and may be the most eloquent evidence for the transport process across the magnetopause. The cold component occasionally has a strong anisotropy in the dusk flank, and the sense of the anisotropy depends on the observed locations: the parallel temperature is enhanced in the tail flank while the perpendicular temperature is enhanced on the dayside. The hot component is nearly isotropic in the tail while the perpendicular temperature is enhanced on the dayside. We discuss possible mechanism that can lead to the observed temperature anisotropies.

The most common cause of neonatal diabetes, KCNJ11 gene mutation, can manifest as a neurological disorder. The most severe form consists of a constellation of developmental delay, epilepsy, and neonatal diabetes (DEND). Intermediate DEND (iDEND) refers to a milder presentation without epilepsy. We present a child with iDEND, for whom insulin injections were replaced with glibenclamide therapy at 17 months of age because of poor glycemic control and delayed motor development. Three months after initiation of glibenclamide, HbA1c decreased from 10.2% to 5.6%. Continuous glucose monitoring indicated that blood glucose fluctuations were suppressed while on glibenclamide. Furthermore, after initiating glibenclamide therapy, the developmental quotient (DQ) for motor ability markedly improved from 60 to 91, whereas the DQ for language and adoptive ability remained as they had been before the sulfonylurea treatment. Sulfonylurea treatment improved glycemic control and motor development in the present patient.

C-type natriuretic peptide-natriuretic peptide receptor B (NPR-B) signaling is critical for endochondral ossification, which is responsible for longitudinal growth in limbs and vertebrae. Biallelic NPR2 mutations cause acromesomelic dysplasia, type Maroteaux, which is bone dysplasia characterized by severe short stature and short limbs. A monoallelic NPR2 mutation has been suggested to mildly impair long bone growth.The goal of this study was to identify and characterize NPR2 mutations among Japanese patients with short stature.We enrolled 101 unrelated Japanese patients with short stature. NPR2 and NPPC were sequenced, and the identified variants were characterized in vitro.In two subjects, we identified two novel heterozygous NPR2 mutations (R110C and Q417E) causing a loss of C-type natriuretic peptide-dependent cGMP generation capacities and having dominant-negative effects. R110C was defective in trafficking from the endoplasmic reticulum to the Golgi apparatus. In contrast, Q417E showed clear cell surface expression.We identified heterozygous NPR2 mutations in 2% of Japanese patients with short stature. Our in vitro findings indicate that NPR2 mutations have a dominant negative effect, and their dominant-negative mechanisms vary corresponding to the molecular pathogenesis of the mutations.

Elevated serum alkaline phosphatase (ALP) is a screening marker for the diagnosis of vitamin D deficiency, which may fail to be diagnosed if serum ALP is not elevated. Here, we describe a case of vitamin D deficiency without elevation of serum ALP. A 1-year-old Japanese girl was referred to our hospital for the evaluation of genu varum. Her serum intact PTH level was elevated, while her serum ALP level was normal. Furthermore, her serum 25-hydroxyvitamin D level was reduced, and her urine phosphoethanolamine (PEA) level was mildly elevated. ALPL gene analysis revealed she was a heterozygous carrier of hypophosphatasia (c.1559delT). Serum intact PTH and urine PEA evaluations were helpful for diagnosing vitamin D deficiency and hypophosphatasia carrier status, respectively. Therefore, the possibility of vitamin D deficiency without elevation of serum ALP should be considered.

A 40-year-old man presented with Cushing's syndrome due to bilateral adrenal hyperplasia with multiple nodules. Computed tomography scan results were atypical demonstrating an enlargement of the bilateral adrenal glands harboring multiple small nodules, but the lesion was clinically diagnosed to be primary pigmented nodular adrenocortical disease (PPNAD) based on both endocrinological test results and his family history. We performed bilateral adrenalectomy and confirmed the diagnosis histologically. An analysis of the patient and his mother's genomic DNA identified a novel mutation in the type Iα regulatory subunit of protein kinase A (PRKAR1A) gene; p.E17X (c.49G>T). This confirmed the diagnosis of PPNAD which is associated with Carney Complex.

Summary Context To date, approximately 35 different POU1F1 mutations have been described in patients with familial and sporadic combined pituitary hormone deficiency (CPHD) from different ethnic backgrounds. The majority are missense mutations clustered within the conserved POU-specific and POU-homeo domains, encoded by exons 4 and 6, respectively. Objectives This study aimed to identify the molecular basis and clinical characteristics of a Japanese CPHD family with a novel POU1F1 mutation. Design The POU1F1 gene was sequenced in identical twin brothers with mild CPHD. The mutation identified was also evaluated in family members as well as 188 Japanese controls and then examined in functional studies. Results A novel heterozygous splice site mutation (Ex2 + 1G>T; c.214 + 1G>T) was detected. This mutation was also present in their undiagnosed mother, but not in any of the controls. In vitro splicing studies suggested this mutation to result in an in-frame skipping of exon 2, thus producing an internally deleted protein lacking most of the R2 transactivation subdomain (TAD-R2). Heterologous expression studies of the mutated POU1F1 protein showed only modest reductions in its transactivation activities in HEK293T cells, while acting as a dominant-negative inhibitor of the endogenous activities of POU1F1 in pituitary GH3 cells. Conclusions This is the first report of a mutation at the exon 2 donor splice site of POU1F1, affecting TAD-R2. The addition of this mutation to the growing list of pathological POU1F1 mutations may provide deeper insights into clinical heterogeneity in the expressions of individual mutations and a better understanding of the structure–function relationships of POU1F1.

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.

Glycogen-storage disease type II (GSDII) is an autosomal recessive disorder caused by a deficiency of acid alpha-glucosidase (GAA). The residual GAA activity is largely related to the severity of the clinical course. Most patients with infantile-onset GSDII do not show any enzyme activity, whereas patients with the late-onset forms of GSDII show various degrees of GAA activity. We performed a molecular genetic study on a Japanese boy with childhood-onset GSDII. The patient was a compound heterozygote for a newly discovered splice-site c.546G>T mutation and a recurrent missense p.R600C mutation, which usually causes the fatal infantile form in a homozygous state. The c.546G>T mutation, which did not alter the amino-acid sequence, was positioned at the last base of exon 2. cDNA-sequencing analysis revealed that c.546G>T was a leaky splice mutation, leading to the production of a normally spliced transcript, which was responsible for the low-level (approximately 10%) expression of the active enzyme in the patient's fibroblasts.

We have developed a new energy/mass spectrometer for medium energy range (10-200 keV/q) ion measurements in the Earth's magnetosphere and interplanetary space. The wide field-of-view ( ~360deg fan) enables acquisition of 3-D distribution functions for all the major ions, by utilizing spacecraft spin motions. The g-factor is much larger than the previous ion mass spectrometers in the medium energy range. The mass analysis unit that measures ion time-of-flights is well designed to realize a lightweight and simple signal processing. Laboratory experiments with a test model show that the performance of mass spectroscopy agrees with numerical simulations. Medium energy ion mass spectrometer with this new design will surely be useful for upcoming space missions in the inner magnetosphere, reconnection regions, and other energetic plasma structures/phenomena in space.

To investigate the cold plasma sheet formation under northward IMF, we study the temperature anisotropies of electrons and two-component protons observed by the Geotail spacecraft. The two-component protons, which are occasionally observed in the dusk plasma sheet near the low-latitude boundary, are the result of spatial mixing of the hot protons of the magnetosphere proper and the cold protons from the solar wind. Recent research focusing on the two-component protons reported that the cold proton component at times has a strong anisotropy, and that the sense of the anisotropy depends on the observed locations. Since electrons have been known to possess a strong parallel anisotropy around the low-latitude boundary layer, we compare anisotropies of electrons and protons to find that the strengths of parallel anisotropies of electrons and the cold proton component are in good correlation in the tail flank. The parallel anisotropy of electrons is stronger than that of the cold proton component, which is attributed to selective heating of electrons. We further find that the strengths of the parallel anisotropies in the tail flank depend on the latitudinal angle of the IMF; strong parallel anisotropies occur under strongly northward IMF. We discuss that the Kelvin-Helmholtz vortices, which developed under strongly northward IMF, and the resultant magnetic reconnection therein may lead to the strong parallel anisotropies observed in the tail flank.

Background Dual oxidase 2 (DUOX2) mutations are a cause of dyshormonogenesis (DH) and have been identified in patients with permanent congenital hypothyroidism (PH) and with transient hypothyroidism (TH). We aimed to elucidate the prevalence and phenotypical variations of DUOX2 mutations. Methods Forty-eight Japanese DH patients were enroled and analysed for sequence variants of DUOX2, DUOXA2, and TPO using polymerase chain reaction-amplified direct sequencing. Results Fourteen sequence variants of DUOX2, including 10 novel variants, were identified in 11 patients. DUOX2 variants were more prevalent (11/48, 22.9%) than TPO (3/48, 6.3%) (p=0.020). The prevalence of DUOX2 variants in TH was slightly, but not significantly, higher than in PH. Furthermore, one patient had digenic heterozygous sequence variants of both DUOX2 and TPO. Conclusions Our results suggest that DUOX2 mutations might be the most common cause of both PH and TH, and that phenotypes of these mutations might be milder than those of other causes.

Strong signals of neutral emissions were detected in association with a solar flare that occurred on 2005 September 7. They were produced by both relativistic ions and electrons. In particular, relativistic neutrons were observed with the solar neutron telescopes (SNTs) located at Mount Chacaltaya in Bolivia and Mount Sierra Negra in Mexico and with neutron monitors (NMs) at Chacaltaya and Mexico City with high statistical significances. At the same time, hard X-rays and γ-rays, which were predominantly emitted by high-energy electrons, were detected by the Geotail and the INTEGRAL satellites. We found that a model of the impulsive neutron emission at the time of the X-ray/γ-ray peak can explain the main peaks of all the detected neutron signals, but failed to explain the long tailed decaying phase. An alternative model, in which the neutron emission follows the X-ray/γ-ray profile, also failed to explain the long tail. These results indicate that the acceleration of ions began at the same time as the electrons but that ions were continuously accelerated or trapped longer than the electrons in the emission site. We also demonstrate that the neutron data observed by multienergy channels of SNTs put constraints on the neutron spectrum.

We surveyed fast current sheet crossings (flapping motions) over the distance range 10–30 RE in the magnetotail covered by the Geotail spacecraft. Since the local tilts of these dynamic sheets are large and variable in these events, we compare three different methods of evaluating current sheet normals using 4-s/c Cluster data and define the success criteria for the single-spacecraft-based method (MVA) to obtain the reliable results. Then, after identifying more than ~1100 fast CS crossings over a 3-year period of Geotail observations in 1997–1999, we address their parameters, spatial distribution and activity dependence. We confirm that over the entire distance covered and LT bins, fast crossings have considerable tilts in the YZ plane (from estimated MVA normals) which show a preferential appearance of one (YZ kink-like) mode that is responsible for these severe current sheet perturbations. Their occurrence is highly inhomogeneous; it sharply increases with radial distance and has a peak in the tail center (with some duskward shift), resembling the occurrence of the BBFs, although there is no one-to-one local correspondence between these two phenomena. The crossing durations typically spread around 1 min and decrease significantly where the high-speed flows are registered. Based on an AE index superposed epoch study, the flapping motions prefer to appear during the substorm expansion phase, although a considerable number of events without any electrojet and auroral activity were also observed. We also present statistical distributions of other parameters and briefly discuss what could be possible mechanisms to generate the flapping motions.

Standing Alfvén waves of 1.1 mHz (~15 min in period) were observed by the Cluster satellites in the mid-tail during 06:00-07:00UT on 8August 2003. Pulsations with the same frequency were also observed at several ground stations near Cluster's footpoint. The standing wave properties were determined from the electric and magnetic field measurements of Cluster. Data from the ground magnetometers indicated a latitudinal amplitude and phase structure consistent with the driven field line resonance (FLR) at 1.1 mHz. Simultaneously, quasi-periodic oscillations at different frequencies were observed in the post-midnight/early morning sector by GOES12 (l0≈8.7), Polar (l0≈11-14) and Geotail (l0≈9.8). The 8August 2003 event yields rare and interesting datasets. It provides, for the first time, coordinated in situ and ground-based observations of a very low frequency FLR in the mid-tail on stretched field lines.

Human chromosomal region 11p15.5, which is homologous to mouse chromosome region 7F5, is a well-known imprinted region. The CDKN1C/KCNQ1OT1 imprinted domain, which is one of two imprinted domains at 11p15.5, includes nine imprinted genes regulated by an imprinting center (IC). The CDKN1C/KCNQ1OT1 IC is a differentially methylated region of KCNQ1OT1(KCNQ1OT-DMR) with DNA methylation on the maternal allele and no methylation on the paternal allele. CDKN1C (alias p57KIP2), an imprinted gene with maternal expression, encoding a cyclin-dependent kinase inhibitor, is a critical gene within the CDKN1C/KCNQ1OT1 domain. In Beckwith-Wiedemann syndrome (BWS), approximately 50% of patients show loss of DNA methylation accompanied by loss of histone H3 Lys9 dimethylation on maternal KCNQ1OT-DMR, namely an imprinting disruption, leading to diminished expression of CDKN1C. In cancer, at least three molecular mechanisms – imprinting disruption, aberrant DNA methylations at the CDKN1C promoter, and loss of heterozygosity (LOH) of the maternal allele – are seen and all three result in diminished expression of CDKN1C. Imprinting disruption of the CDKN1C/KCNQ1OT1 domain is involved in the development of both BWS and cancer and it changes the maternal epigenotype to the paternal type, leading to diminished CDKN1C expression. In this review, we describe recent advances in epigenetic control of the CDKN1C/KCNQ1OT1 imprinted domain in both humans and mice.

Recent loss-of-function and gain-of-function studies have revealed that transcription factor Sox9 is required for testis formation by governing Sertoli cell differentiation, and thereafter regulating transcription of Sertoli marker genes. In the present study, we identified a novel isoform of Vinexin, which is expressed in somatic cells but not germ cells of sexually indifferent stages of fetal gonads. After the sex is determined, the expression continues in testicular Sertoli cells. Immunohistochemical analyses with a specific antibody to Vinexin indicated that Vinexin gamma is localized in the cytoplasm. Functional studies with C3H10T1/2 cells showed that Vinexin gamma acted as a scaffold protein to activate MEK and ERK through interaction with c-Raf and ERK. Ultimately, Sox9 transcription was induced by Vinexin gamma. This up-regulation of Sox9 expression disappeared when the cells were treated with a specific MEK inhibitor, U0126. To determine the role of Vinexin gamma during gonad formation, the gene was disrupted by targeted mutagenesis. The phenotype displayed by the mice indicated that ERK activation was decreased in the Vinexin gamma(-/-) XY gonads, and Sox9 expression was down-regulated. Thus, Vinexin gamma seems to be implicated in regulation of Sox9 gene expression by modulating MAPK cascade in mouse fetal gonads.

Accepted: 2003-09-15, 資料番号: SA1004091000

Congenital lipoid adrenal hyperplasia (lipoid CAH) is the most severe form of CAH in which the synthesis of all gonadal and adrenal cortical steroids is markedly impaired. Lipoid CAH may be caused by the defect in either the steroidogenic acute regulatory (StAR) protein or the P450scc. More than 34 different mutations in StAR gene have been identified. Clinically, most of the patients manifest adrenal insufficiency from 1 day to 2 months of age, but some patient show delayed onset of adrenal insufficiency. Affected 46, XY subjects do not show pubertal development, whereas affected 46, XX subjects undergo spontaneous feminization, breast development and cyclical vaginal bleeding at the usual age of puberty. X-linked adrenal hypoplasia congenital (AHC) is a rare congenital adrenal disorder characterized by severe adrenal insufficiency and hypogonadotropic hypogonadism. More than 80 different several intragenic mutations of DAX-1 have been identified. The failure of pubertal development may be caused by either abnormal hypothalamic or pituitary regulation of gonadotropin secretion. In addition, although the testicular steroidogenesis is largely intact, the functional maturity of Sertoli cells and also spermatogenesis are impaired. The type of mutation does not predict clinical phenotype. Thus, unified mechanism how DAX-1 gene defect gives rise to adrenal insufficiency, hypothalamic/pituitary hypogonadism and impaired spermatogenesis remains established.

Dax-1 [dosage-sensitive sex reversal-adrenal hypoplasia congenita critical region on the X chromosome, gene 1 (NR0B1)] is an orphan nuclear receptor acting as a suppressor of Ad4 binding protein/steroidogenic factor 1 [Ad4BP/SF-1 (NR5A1)] and as an anti-Sry factor in the process of gonadal sex differentiation. The roles of these nuclear receptors in the differentiation of the gonads and the adrenal cortex have been established through studies of the mutant phenotype in both mice and humans. However, the mechanisms underlying transcriptional regulation of these genes remain largely unknown. Here, we examined the relationship between Dax-1 gene transcription and the Wnt4 pathway. Reporter gene analysis revealed that Dax-1 gene transcription was activated by β-catenin, a key signal-transducing protein in the Wnt pathway, acting in synergy with Ad4BP/SF-1. Interaction between β-catenin and Ad4BP/SF-1 was observed using yeast two-hybrid and in vitro pull-down assays. The region of Ad4BP/SF-1 essential for this interaction consists of an acidic amino acid cluster, which resides in the first helix of the ligand-binding domain. Mutation of the amino acid cluster impaired transcriptional activation of Dax-1 as well as interaction of Ad4BP/SF-1 with β-catenin. These results were supported by in vivo observations using Wnt4 gene-disrupted mice, in which Dax-1 gene expression was decreased significantly in sexually differentiating female gonads. We thus conclude that Wnt4 signaling mediates the increased expression of Dax-1 as the ovary becomes sexually differentiated.

Accepted: 2003-04-28, 資料番号: SA1002460000

Background: The DAX-1 (also known as AHC) gene encodes an unusual member of the nuclear receptor superfamily, and the gene product plays a pivotal role during gonadal and adrenal differentiation. Mutations of the human DAX-1 gene cause X-linked adrenal hypoplasia congenita associated with hypogonadotropic hypogonadism. However, the molecular mechanisms underlying the transcriptional regulation of the gene are not well understood. Results: Sexually dimorphic expression of Dax-1 (NR0B1) in the adrenal cortex was observed by RT-PCR, Western blotting and immunohistochemistry. The differential expression was abolished by gonadectomy and was restored again by sex steroid replacement. Our results suggested that the Dax-1 gene transcription is suppressed by androgens and androgen receptor (AR/NR3C4). Dax-1 gene transcription is regulated by Ad4BP/SF-1 (NR5A1), therefore we investigated the functional correlation between A4BP/SF-1 and AR. Interestingly, AR down-regulated the Dax-1 gene transcription mediated by Ad4BP/SF-1 in the presence of the ligand. DNA binding by AR was not essential for the suppressive action, however the suppression seemed to be dependent on the promoter contexts. An interaction between Ad4BP/SF-1 and AR was detected in the presence of the ligand for AR. Conclusion: The present study revealed that the expression of Dax-1 in the adrenal cortex is regulated by androgen and the receptor. Interestingly, AR acts as a suppressor in the presence of the ligand through interaction with Ad4BP/SF-1.

Efficient electron acceleration in magnetic reconnection has been sometimes observed in the earth's magnetotail. We find that the energy spectrum has a suprathermal population above a few keV, and more importantly the higher energy spectrum can be fitted by exp(−αv). A simple model to explain the suprathermal electrons based on a Fermi acceleration process is proposed.

Intermittent enhancements of lobe ions in density and velocity were observed by the GEOTAIL spacecraft in the distant magnetotail (∼100–200 RE). They were observed after the passage of plasmoids, accompanying south-to-north bipolar variations in Bz, which are opposite in polarity to those observed with plasmoids or traveling compression regions. The peaks in the ion density occurred when Bz changed from south to north (i.e., when Bz = 0). To explain these observations, a model is presented in which the magnetotail shrinks behind a plasmoid. It is suggested that after the formation of a plasmoid the near-Earth neutral line runs tailward following the plasmoid. The delay between the plasmoid passage and the ion enhancement observed by the same spacecraft is ∼5–70 min, depending on as yet unknown reasons.

The suprathermal electrons of ≥20 keV that extend from the hot thermal electron with 2–3 keV temperature are sometimes observed in Earth's magnetosphere in association with reconnection. We study the origin of the hot and suprathermal electrons in terms of the kinetic magnetic reconnection process by using the two-dimensional particle-in-cell simulation. We find that the hot and suprathermal electrons can be formed in the nonlinear evolution of a large-scale magnetic reconnection. The electrons are, at the first stage, accelerated in the elongated, thin, X-type current sheet. Next the preheated/accelerated electrons are transported to the stronger magnetic field region produced by piling up of magnetic field lines due to colliding of the fast reconnection outflow with the preexisting plasma. In this region they are further accelerated owing to the ∇B drift and the curvature drift. The mirror force of the reconnecting magnetic fields, the effective pitch angle scattering that occurs when the Larmor radius is comparable to the magnetic field line curvature radius, and the broadband waves excited by the Hall electric current are the other important agents to control the particle acceleration.

We present an observation of broadband transverse waves (BTW) below 1 Hz in the afternoon sector of the magnetosphere at about L ∼ 10. We find that the BTW correlate well with density enhancements and bidirectional electron flows. Characteristics of the BTW are summarized as follows. The wave amplitude varies within a few periods, which results in a broad frequency band in the Fourier spectra. Only perturbations transverse to the background magnetic field are observed. The amplitude ratio of electric to magnetic field fluctuations is close to the local Alfven speed, so that the wave mode is suggested to be Alfven waves. The Poynting flux is directed away from the equatorial region toward the ionosphere. We have assessed various resonance mechanisms (Landau resonance, cyclotron resonance, and resonance with bouncing electrons) but find that none gives a compelling interpretation of the observation, which thus requires future study.

Chicken ovalbumin upstream promoter-transcription factor (COUP-TF), DAX-1, and steroidogenic factor-1 (SF-1) are orphan members of the nuclear hormone receptor superfamily. COUP-TF and DAX-1 have been shown to negatively regulate the transcriptional activity of SF-1, a steroidogenic cell-specific activator of various steroidogenic cytochrome P450 genes. We therefore examined the expression levels and immunolocalization of COUP-TF, DAX-1, and SF-1 in human adrenal gland (NL) and adrenocortical adenomas, and compared the results with CYP17 expression levels and its enzyme activities to study their potential correlation with adrenocortical steroidogenesis. In NL (n = 10), expressions of COUP-TF, DAX-1, and SF-1 were detected in the nuclei of adrenocortical cells, but not in the medulla. In cortisol-producing adenomas causing Cushing syndrome (CS, n = 20), CYP17 expression was upregulated (298 +/- 2% vs NL 98 +/- 4%), whereas expression levels of both COUP-TFs (COUP-TFI, 52 +/- 5% vs NL 98 +/- 4%; COUP-TFII, 18 +/- 4% vs NL 98 +/- 4%) and DAX-1 (42 +/- 4% vs NL 100 +/- 4%) were reduced. In deoxycorticosterone-producing adenomas (DOC, n = 2), on the other hand, CYP17 expression was extremely reduced (8 and 12% vs NL 98 +/- 4%), whereas DAX-1 expression increased markedly (350 and 360% vs NL 100 +/- 4%). Expression levels of SF-1 did not differ between NL (100 +/- 8%) and CS (106 +/- 10%), but its expression appeared to be decreased in DOC (25 and 20%). These results showed CYP17 expression to be upregulated and downregulated in CS and DOC, respectively, in a manner reciprocal to that of its repressors, COUP-TF and/or DAX-1. In summary, the results indicate that co-localization of COUP-TF, DAX-1, and SF-1 in NL was lost in adrenocortical tumors and that these orphan receptors play an important role in the regulation of steroidogenesis in human adrenals.

Accepted: 2000-09-19, 資料番号: SA1001274000

Two nuclear receptors, Ad4BP/SF-1 and Dax-1, are essential regulators for development and function of the mammalian reproductive system. Similarity in expression sites, such as adrenal glands, gonads, pituitary, and hypothalamus, suggests a functional interaction, and the phenotype similarities were manifested in Ad4BP/SF-1-deficient mice and in cases of natural human mutations of Dax-1. In this study, quantitative reverse transcriptase polymerase chain reaction analyses revealed that expression profiles of Dax-1 in embryonic gonads are different between the two sexes and also from those of Ad4BP/SF-1. Immunohistochemical analyses clarified the spatial and temporal expressions of the Dax-1 protein during development of tissues composing the hypothalamic-pituitary-gonadal axis. During gonadal development, Dax-1 occurred after Ad4BP/SF-1 exhibiting a sexually dimorphic expression pattern at indifferent stages, indicating a possibility of Dax-1 involvement in earliest sex differentiation. When cord formation begins in the testis at embryonic day 12.5 (E12.5), Dax-1 was expressed strongly in Sertoli cells, but its expression level markedly decreased in Sertoli cells and increased in interstitial cells between E13.5 and E17.5. In the female, Dax-1 was strongly expressed in the entire ovarian primordium from E12.5 until E14.5, and then its expression level was decreased and limited to cells near the surface epithelium between E17.5 and postnatal day 0 (P0). During postnatal development of the testis, the variable staining of Dax-1 in Sertoli cells was detected as early as P7 and Dax-1-expressing Leydig cells became rare. In the postnatal ovary, Dax-1 expression was detected in granulosa cells with variable staining intensity, and occasionally in interstitial cells. During pituitary organogenesis, Dax-1 but not Ad4BP/SF-1 was expressed in the dorsal part of Rathke's pouch from E9.5. Later in development after E14.5, the distribution of Dax-1 overlapped with that of Ad4BP/SF-1, being restricted to gonadotropic cells in the anterior pituitary. In the ventromedial hypothalamus (VMH), Dax-1 and Ad4BP/SF-1 were mostly colocalized throughout the embryonic and postnatal development. Thus, the coexpression of Dax-1 and Ad4BP/SF-1 indicates their closely related functions in the development of the reproductive system. Furthermore, we noticed the presence of cells that express Dax-1 but not Ad4BP/SF-1, further indicating additional functions of Dax-1 in an Ad4BP/SF-1-independent molecular mechanism.

It has been demonstrated that the mammalian Ad4BP/SF-1 (NR5A1) gene is regulated precisely in sex, tissue, and developmental stage specific manners. To clarify the complex transcriptional regulation, we investigated in the present study whether the gene transcription is regulated by multiple promoters accompanied by noncoding first exons. Novel first exons (Io and Ig) were identified downstream of the already identified exon Ia. Nucleotide sequences revealed that Ia and Ig exons were well conserved, whereas Io exon was less conserved among the mouse, rat, and human genes. Interestingly, the splice donor of the mouse and human Io and human Ig exons do not satisfy the consensus sequence. Transcripts containing Ia, Io, and Ig were detected in all rat tissues examined, while the transcript containing Io was undetectable in the corresponding tissues of mice. The lack of exon Io usage in the mouse was confirmed by transient transfection assays with cultured cells. Quantitative RT-PCR analysis revealed that the transcript containing Ig exon was the main product in the pituitary but significantly less in the spleen, suggesting that the regulation of Ad4BP/SF-1 gene transcription in the pituitary and spleen is distinct from that of other tissues. The above findings, together with the structural abnormality at the splice donor site, suggest that acquisition of the multiple first exons enables the Ad4BP/SF-1 gene to be regulated differentially in different animal species and in different tissues in the same animal.

For several hours on March 24, 1995, the Geotail spacecraft remained near the duskside magnetotail boundary some 15 RE behind the Earth while the solar wind remained very quiet (V=330 km s−1, n=14–21 cm−3) with a very steady 11-nT northward magnetic field. Geotail experienced multiple crossings of a boundary between a dense (n= 19 cm−3), cool (Tp=40 eV), rapidly flowing (V=310 km s−1) magnetosheath plasma and an interior region characterized by slower tailward velocities (V=100 km s−1), lower but substantial densities (n=3 cm−3) and somewhat hotter ions (220 eV). The crossings recurred with a roughly 3-min periodicity, and all quantities were highly variable in the boundary region. The magnetic field, in fact, exhibited some of the largest fluctuations seen anywhere in space, despite the fact that the exterior magnetosheath field and the interior magnetosphere field were both very northward and nearly parallel. On the basis of an MHD simulation of this event, we argue that the multiple crossings are due to a Kelvin-Helmholtz instability at the boundary that generates vortices which move past the spacecraft. A determination of boundary normals supports Kelvin-Helmholtz theory in that the nonlinear steepening of the waves is seen on the leading edge of the waves rather than on the trailing edge, as has sometimes been seen in the past. It is concluded that the Kelvin-Helmholtz instability is an important process for transferring energy, momentum and particles to the magnetotail during times of very northward interplanetary magnetic field.

CYP17 gene transcription is activated by SF-1 binding to a cyclic AMP-responsive sequence within the promoter region of the gene, and its transcription is inhibited by COUP-TF binding to the sequence. Another orphan receptor, DAX-1, is shown to act as a suppressor of SF-1-mediated transcription. We examined the expression level of these orphan receptors in adrenocortical tumors and compared the results with CYP17 expression. CYP17 was highly expressed in cortisol-producing adenomas, whereas COUP-TF and DAX-1 expression levels were very low. In deoxycorticosterone-producing adenomas, on the other hand, CYP17 expression was extremely low, whereas DAX-1 was highly expressed and SF-1 expression was slightly decreased. In conclusion, the reciprocal expression of CYP17 and the transcriptional repressors COUP-TF and DAX-1 indicates that these orphan receptors have a pathophysiologic role in the excessive hormone production in cortisol- and deoxycorticosterone-producing adrenocortical tumors.