Reactive sulfur species regulate tRNA methylthiolation and contribute to insulin secretion.

The 2-methylthio (ms2) modification at A37 of tRNAs is critical for accurate decoding, and contributes to metabolic homeostasis in mammals. However, the regulatory mechanism of ms2 modification remains largely unknown. Here, we report that cysteine hydropersulfide (CysSSH), a newly identified reactive sulfur species, is involved in ms2 modification in cells. The suppression of intracellular CysSSH production rapidly reduced ms2 modification, which was rescued by the application of an exogenous CysSSH donor. Using a unique and stable isotope-labeled CysSSH donor, we show that CysSSH was capable of specifically transferring its reactive sulfur atom to the cysteine residues of ms2-modifying enzymes as well as ms2 modification. Furthermore, the suppression of CysSSH production impaired insulin secretion and caused glucose intolerance in both a pancreatic ß-cell line and mouse model. These results demonstrate that intracellular CysSSH is a novel sulfur source for ms2 modification, and that it contributes to insulin secretion.

[Tuberculosis of the thyroid gland mimicking thyroid carcinoma in the elderly].

A 76-year-old woman with a 10-year history of chronic glomerulonephritis was treated at a clinic after presenting with a gradual worsening of the renal function. The patient had no history of tuberculosis. She was subsequently hospitalized for uremic symptoms and treated with internal shunt insertion and dialysis. Thyroid ultrasonography was performed to screen for secondary hyperparathyroidism, which revealed a calcified thyroid mass and cervical lymph node swelling. Fine-needle aspiration biopsy was thus conducted to assess suspected thyroid cancer. The cytological findings showed few follicular epithelial cells, without any signs of malignancy. However, a diagnosis of thyroid cancer continued to be strongly suspected based on the imaging features. Total thyroidectomy and bilateral cervical regional lymph node dissection were therefore performed, and the pathological examination of the thyroidectomy specimen disclosed scattered epithelioid granulomas with caseous necrosis in the entire right lobe as well as the cervical lymph nodes. Based on these findings, the patient was diagnosed with thyroid tuberculosis. As the symptoms and imaging findings of tuberculosis are nonspecific in elderly patients, it is necessary to consider this disease in this population. We therefore propose the inclusion of thyroid tuberculosis in the differential diagnosis of elderly patients who present with malignant thyroid tumors on aspiration biopsy cytology, regardless of whether or not they have a previous history of tuberculosis.

Efficacy of combination treatment with fingolimod (FTY720) plus pathogenic autoantigen in a glucose-6-phosphate isomerase peptide (GPI325-339)-induced arthritis mouse model.

Fingolimod (FTY720) is known to have a significant therapeutic effect in various autoimmune disease models. Here, we examined FTY720 in a model of rheumatoid arthritis, induced by immunizing DBA/1 mice with a peptide consisting of residues 325 through 339 of glucose-6-phosphate isomerase (GPI325-339). The efficacy was evaluated in terms of macroscopic findings, inflammatory cell infiltration and autoantibody level. Prophylactic administration of FTY720 from the day of immunization significantly suppressed the development of paw swelling, but therapeutic administration of FTY720 from onset of symptoms on day 8-9 was less effective. Interestingly, however, combination treatment with FTY720 plus GPI325-339 for 5 d after onset of symptoms significantly reduced the severity of symptoms in all mice, and no relapse occurred after booster immunization. Taking into account the reported mechanism of action of FTY720, these results indicate that combination treatment with FTY720 plus pathogenic autoantigen might efficiently induce immune tolerance by sequestering circulating autoantigen-specific lymphocytes from blood and peripheral tissues to the secondary lymphoid tissues. Combination treatment with FTY720 plus pathogenic autoantigen may become a breakthrough treatment for remission-induction in patients with autoimmune diseases including rheumatoid arthritis.

Estimation of daily intake of food additives by Japanese young children using the market basket method in 2018.

To estimate the daily intake of food additives by young children aged 1-6 years in Japan, an intake survey was conducted in 2018 using the market basket method for food additives, including twelve types of colourants, three kinds of preservatives, three kinds of sweeteners and two kinds of food manufacturing agents. A list of the daily consumption of processed foods was prepared based on a special survey (MHLW 2011) and used for the estimation. The results of the survey showed that the food additives with the highest daily intake were phosphorus compounds (phosphoric acid and its salts; 11.2 mg/kg bw/day, expressed as phosphorus), followed by propylene glycol (0.80 mg/kg bw/day). The daily intake of other food additives ranged from 0 to 0.20 mg/kg bw/day. The estimated daily intake of each food additives by young children was compared with the acceptable daily intake (ADI) or maximum tolerable daily intake (MTDI). The highest ratio of the estimated daily intake to ADI was 3.2% for propylene glycol, whereas the ratios of the estimated daily intake to ADI for colourants, preservatives and sweeteners ranged from 0 to 1.1% (benzoic acid). The ratio of the estimated daily intake to MTDI for phosphorus compounds was 16%.

[Case of MPO-ANCA-associated vasculitis with membranous nephropathy].

We experienced a rare case of membranous glomerulopathy(MN) with myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA)-associated glomerulonephritis. A 79-year-old woman was admitted to our hospital because of pyrexia, microscopic hematuria, massive proteinuria and positive MPO-ANCA on June, 2007. We diagnosed her as MPO-ANCA-associated vasculitis accompanied by nephrotic syndrome. Intravenous methylprednisolone sodium succinate (500 mg/day for three days)therapy and oral prednisolone (40 mg/day) improved her fever, hematuria, serum CRP and MPO-ANCA titer. Renal biopsy was performed and light microscopic examination of a renal biopsy specimen containing 21 glomeruli revealed global sclerosis in 3 and thickened basement membrane in 18 of the glomeruli. Fibrocellular crescents were found in 2 and segmental necrosis in 1. Immunofluorescence microscopy showed granular staining with IgG and C3 along the capillary walls. Electron microscopic examination disclosed subepithelial dense deposits in the thickened glomerular basement membrane. To investigate the pathogenesis of MN, IgG subclass was examined by means of immunofluorescence microscopy. IgG1 and IgG4 were deposited on the glomerular capillary walls, which suggested secondary MN. However, this patient refused to take any medicines and had no disease such as infection or cancer which cause secondary MN. MPO staining was performed to investigate the relation of MPO-anti-MPO antibody immune complex in the pathogenesis of MN. The results showed only a few MPO-positive cells in the glomeruli and MPO stains on the glomerular capillary walls near the MPO-positive cells. These findings suggested that the patient had MPO-ANCA-associated glomerulonephritis superimposed on idiopathic MN. In the case of nephrotic syndrome with MPO-ANCA, we should consider the coexistence of other types of glomerulonephritis, especially MN.

Gonadal mosaicism of a TAZ (G4.5) mutation in a Japanese family with Barth syndrome and left ventricular noncompaction.

TAZ (G4.5) was initially identified as the gene associated with Barth syndrome and left ventricular noncompaction (LVNC). The purpose of this study was to investigate patients with LVNC for disease-causing mutations in TAZ. In 124 Japanese patients, including 50 families, mutation analysis of TAZ was performed using DNA sequencing. A splice donor mutation was identified in two brothers with Barth syndrome and LVNC, and a sister who was asymptomatic. However, the variant was not identified in either parent or the maternal grandparents, all of whom were asymptomatic. Due to the recurrent inheritance of this variant by each of the children we concluded that this was evidence of gonadal mosaicism in the obligate carrier mother, the first reported occurrence of this in Barth syndrome.

Infliximab reduces the cytokine-mediated inflammation but does not suppress cellular infiltration of the vessel wall in refractory Kawasaki disease.

The aim of our study was to evaluate the efficacy of infliximab for the treatment of patients with refractory Kawasaki disease (KD) and investigate the dynamic changes of cytokines during infliximab treatment. We have performed a study of cytokine and proinflammatory molecule levels in 43 KD patients including 18 responders to IVIG, 14 nonresponders, and 11 patients treated with infliximab. We determined serum levels of soluble TNF receptor I (sTNFR I) and IL-6, as well as VEGF, damage associated molecular pattern (DAMP) molecules; myeloid-related protein (MRP)8/MRP14 and S100A12 sequentially. In eight patients, fever subsided immediately upon infliximab treatment. Four patients, who started infliximab after 12 d of illness, developed coronary artery lesions. Each of the cytokines was elevated before infliximab treatment in all patients. Although serum levels of proinflammatory cytokines decreased dramatically after infliximab treatment, DAMP molecules and VEGF and markers of local tissue damage were not suppressed. In contrast, in IVIG responders all cytokines decreased markedly after IVIG treatment. We show that infliximab is one of the adoptive therapies in refractory KD patients. Different behaviors of proinflammatory cytokines and DAMP molecules and VEGF after infliximab treatment suggest that infliximab is effective for suppression of cytokine-mediated inflammation, but could not completely block local vasculitis.

Successful cardiac resynchronization therapy in a 3-year-old girl with isolated left ventricular non-compaction and narrow QRS complex: a case report.

Cardiac resynchronization therapy (CRT) is a new method of treatment for refractory heart failure. However, for children, its indication, efficacy, and long-term prognosis remain unclear. This study describes the use of CRT for a 3-year-old girl with intractable heart failure caused by isolated left ventricular non-compaction (LVNC) with narrow QRS complex. Echocardiography showed diffuse hypokinetic left ventricular (LV) wall motion (ejection fraction =29.3%) with dyssynchrony between the apex, posterior and lateral walls, where numerous prominent trabeculations existed, and severe mitral regurgitation. Biventricular resynchronization using epicardial pacing leads was performed under general anesthesia. Pacing sites for optimal synchronization in the ventricular walls where chosen using tissue Doppler imaging, and AV delay was adjusted to achieve maximal systolic blood pressure and maximal cardiac output. Over a follow-up period of 2 years, she exhibited significant and sustained improvement in LV function and clinical symptoms. BNP levels decreased from 1,960 to 82 pg/ml. QRS duration (103 ms) on ECG did not change after CRT. We conclude that pediatric CRT provides a highly useful adjunct for the treatment of heart failure, even in patients with a narrow QRS duration, and might improve the prognosis of patients with LVNC.

Long-distance ferromagnetic coupling through spin polarization in a linear heterotrinuclear iron(III)-copper(II)-iron(III) complex derived from 5-ferrocenyl-2-aminotropone.

A novel hetrotrinuclear complex composed of two ferrocenium-ion moieties and copper complex of 2-aminotropones showed relatively strong intramolecular ferromagnetic coupling in the solid states owing to spin polarization mechanism.

Structural requirements for the flavonoid fisetin in inhibiting fibril formation of amyloid beta protein.

Fisetin (3,3',4',7-tetrahydroxyflavone) has been found to be neuroprotective, induce neuronal differentiation, enhance memory, and inhibit the aggregation of the amyloid beta protein (Abeta) that may cause the progressive neuronal loss in Alzheimer's disease. The diverse collection of biological activities of this compound may lead to a new type of therapeutic drug for Alzheimer's disease. As the first step to design even more effective drugs based upon the structure of fisetin, the present study investigated the structural requirements for the anti-amyloidogenic activity of fisetin by comparing the effects of several structurally related flavonoids on Abeta fibril formation in vitro. Abeta1-42 (20muM) and the flavonoids were incubated for 0-48h at 37 degrees C, and fibril formation was quantitatively determined by the thioflavin T fluorescence assay. Among ten flavonoids tested, fisetin, 3',4',7-trihydroxylflavone, 3,3',4'-trihydroxyflavone, luteolin, quercetin and myricetin inhibited Abeta fibril formation. On the other hand, 3,3',7-trihydroxyflavone, 5-deoxykaempferol, chrysin and kaempferol enhanced Abeta fibril formation. These results suggest that the 3',4'-dihydroxyl group, but not the 3- or 7-hydroxyl group, is essential for the inhibitory effect of fisetin on Abeta fibril formation.

Distinct clones are associated with the development of transient myeloproliferative disorder and acute megakaryocytic leukemia in a patient with Down syndrome.

Children with Down syndrome (DS) have an approximately 20-fold higher incidence of leukemia than unaffected children, and most leukemia cases with DS present as acute megakaryocytic leukemia (AMKL). At least 10% of neonates with DS develop transient myeloproliferative disorder (TMD), and 20% to 30% of patients with TMD develop AMKL. Mutations in the GATA1 gene are identified not only in AMKL patients but also in TMD patients; however, sequential analysis of GATA1 is not often performed in the same patients. We describe a child with DS who developed TMD followed by AMKL and have identified different mutations in the GATA1 gene during the course of TMD and AMKL. Distinct clones were associated with the development of TMD and AMKL in this patient.

Oxytocin Protects against Stress-Induced Cell Death in Murine Pancreatic ß-Cells.

Oxytocin (Oxt) is a key neuropeptide that regulates maternal behaviors as well as social behaviors in mammals. Interestingly, recent studies have shown that the impairment of Oxt signaling is associated with the disturbance of metabolic homeostasis, resulting in obesity and diabetes. However, the molecular mechanism by which Oxt signaling controls metabolic responses is largely unknown. Here, we report that Oxt signaling attenuates the death of pancreatic beta cells in islets exposed to cytotoxic stresses. The protective effect of Oxt was diminished in islets isolated from oxytocin receptor knockout (Oxtr(-/-)) mice. Oxtr(-/-) mice developed normally, but exhibited impaired insulin secretion and showed glucose intolerance under a high-fat diet. Mechanistically, the deficiency of Oxtr impaired MAPK/ERK-CREB signaling, which exaggerated the endoplasmic reticulum stress response and ultimately increased the death of beta cells in pancreatic islets under stressed conditions. These results reveal that Oxt protects pancreatic beta cells against death caused by metabolic stress, and Oxt signaling may be a potential therapeutic target.

Neutrophil-derived S100A12 is profoundly upregulated in the early stage of acute Kawasaki disease.

Neutrophil-derived S100A12 is strongly upregulated during the acute stage of Kawasaki disease and decreases significantly in response to intravenous immune globulin (IVIG) treatment, whereas in nonresponders, serum concentrations increases after initial treatment. Decreased S100A12 expression in neutrophils was detected initially in nonresponders but increased significantly after IVIG treatment, suggesting delayed inflammatory response of neutrophils in nonresponders. Furthermore, in vitro S100A12 secretion increased with tumor necrosis factor-alpha (TNF-alpha) stimulation, whereas intracellular levels were lower in neutrophils with the higher TNF-alpha dose, suggesting intracellular depletion. S100A12 expression in neutrophils appears to reflect responsiveness to IVIG treatment and is possibly involved in the pathophysiology of acute vasculitis.

3,3',4',5,5'-Pentahydroxyflavone is a potent inhibitor of amyloid ß fibril formation.

The natural flavonoid fisetin (3,3',4',7-tetrahydroxyflavone) is neurotrophic and prevents fibril formation of amyloid ß protein (Aß). It is a promising lead compound for the development of therapeutic drugs for Alzheimer's disease. To find even more effective drugs based on the structure of fisetin, we synthesized a series of fisetin analogues lacking the 7-hydroxyl group and compared their effects on Aß fibril formation determined by the thioflavin T fluorescence assay. 3,3',4'-Trihydroxyflavone and 3',4'-dihydroxyflavone inhibited Aß fibril formation more potently than fisetin or 3',4',7-trihydroxyflavone, suggesting that the 7-hydroxy group is not necessary for anti-amyloidogenic activity. 3,3',4',5'-Tetrahydroxyflavone and 3',4',5'-trihydroxyflavone inhibited Aß fibril formation far more potently than 3,3',4'-trihydroxyflavone and 3',4'-dihydroxyflavone, suggesting that 3',4',5'-trihydroxyl group of the B ring is crucial for the anti-amyloidogenic activity of flavonoids. Based on the structure-activity relationship, we synthesized 3,3',4',5,5'-pentahydroxyflavone, and confirmed that this compound is the most potent inhibitor of Aß fibril formation among fisetin analogues that have been tested. Cytotoxicity assay using rat hippocampal neuron cultures demonstrated that Aß preincubated with 3,3',4',5,5'-pentahydroxyflavone was significantly less toxic than Aß preincubated with vehicle. 3,3',4',5,5'-Pentahydroxyflavone could be a new therapeutic drug candidate for the treatment of Alzheimer's disease.

Deficit of tRNA(Lys) modification by Cdkal1 causes the development of type 2 diabetes in mice.

The worldwide prevalence of type 2 diabetes (T2D), which is caused by a combination of environmental and genetic factors, is increasing. With regard to genetic factors, variations in the gene encoding Cdk5 regulatory associated protein 1-like 1 (Cdkal1) have been associated with an impaired insulin response and increased risk of T2D across different ethnic populations, but the molecular function of this protein has not been characterized. Here, we show that Cdkal1 is a mammalian methylthiotransferase that biosynthesizes 2-methylthio-N6-threonylcarbamoyladenosine (ms2t6A) in tRNA(Lys)(UUU) and that it is required for the accurate translation of AAA and AAG codons. Mice with pancreatic ß cell-specific KO of Cdkal1 (referred to herein as ß cell KO mice) showed pancreatic islet hypertrophy, a decrease in insulin secretion, and impaired blood glucose control. In Cdkal1-deficient ß cells, misreading of Lys codon in proinsulin occurred, resulting in a reduction of glucose-stimulated proinsulin synthesis. Moreover, expression of ER stress-related genes was upregulated in these cells, and abnormally structured ER was observed. Further, the ß cell KO mice were hypersensitive to high fat diet-induced ER stress. These findings suggest that glucose-stimulated translation of proinsulin may require fully modified tRNA(Lys)(UUU), which could potentially explain the molecular pathogenesis of T2D in patients carrying cdkal1 risk alleles.

Structural, electronic and magnetic properties of Cu(II) complexes of 2-substituted tropones bearing a ferrocenyl group at 5-position.

Heterotrinuclear Fe(II)-Cu(II)-Fe(II) complexes [Cu(FcTropOMe)(2)(H(2)O)(2)](OTf)(2) (FcTropOMe = 5-ferrocenyl-2-methoxytropone) (1), [Cu(FcTropNEt(2))(2)](OTf)(2) (FcTropNEt(2) = 2-(N,N-diethylamino)-5-ferrocenyltropone) (2) and [Cu(FcTropNEt)(2)] (FcTropNEt = 2-(N-ethylamino)-5-ferrocenyltroponate) (3) were synthesized. In addition, a hexafluorophosphate salt of heterotrinuclear Fe(III)-Cu(II)-Fe(III) complex [Cu(FcTropNEt)(2)](2+) (3(2+)) was successfully obtained as single crystals by electrochemical oxidation of 3. By comparing the X-ray structures and absorption spectra of dicationic complexes 1 and 2, the 2-(diethylamino)tropone ligand was found to induce a greater intramolecular charge transfer (CT) from ferrocenyl to tropone-Cu(II) moieties than the 2-methoxytropone ligand. On the other hand, 3(2+) showed a broad CT band in the near-infrared (NIR) region similar to 2, which can be assigned to a transition from troponato-Cu(II) to ferrocenium moieties. As for the magnetic properties of 3(2+)(PF(6)(-))(2), measurements of temperature dependence of magnetic susceptibility and ESR on the solid state and in solution revealed the presence of a strong ferromagnetic interaction (J(Fe-Cu) = +12.0 cm(-1)) between the low spin Fe(III) ion with S = 1/2 and Cu(II) ion with S = 1/2 despite a long distance pathway via the aminotroponato and cyclopentadienyl moieties. DFT calculations supported this intramolecular ferromagnetism, which is induced by a spin polarization mechanism through the pi-spacers.

Characterization of ventricular myocardial performance in the fetus by tissue Doppler imaging.

BACKGROUND: Clinically useful indices of fetal cardiac function have not been fully delineated for tissue Doppler imaging (TDI). METHODS AND RESULTS: In the present study, 56 pregnancies between the 17(th) and 38(th) weeks of gestation included 38 normal fetuses, 6 cases of hydrops fetalis (HF), and 12 of intrauterine growth retardation (IUGR). Peak velocity in early diastole (E) was measured by pulsed-wave Doppler and the peak annular velocities in systole (Sa) and early diastole (Ea) were measured by TDI. The ratio between flow velocity and annular velocity in early diastole (E/Ea) and the ratio of the Sa of right ventricle to that of the left ventricle (RVSa/LVSa) were estimated. In all fetuses with HF, LVSa was <2 cm/s and LVE/Ea was >13. RVSa/LVSa in the HF group was significantly higher than that in the normal group, and RVSa/LVSa in the IUGR group was significantly lower than that in the normal group. CONCLUSIONS: A combination of low LVSa and high LVE/Ea shows reduced global myocardial performance of the LV, and would be one of the useful indices for quantitative assessment in high-risk pregnancies. Changes in the RVSa/LVSa ratio may reflect afterload changes in both ventricles and compensatory cardiovascular mechanisms occurring during the process of placental insufficiency and heart failure.

Assessment of variables affecting flow propagation velocity of the left ventricle in healthy children.

BACKGROUND: The purpose of the present study was to establish the normal values of flow propagation velocity (FPV) in healthy children and examine the variables that affect FPV in clinical situations. METHODS: Two hundred and thirty- five healthy children and adolescents were assessed (aged 0-22.6 years, mean age 7.4 +/- 5.4 years; male, n = 142; female, n = 93). FPV was obtained from an apical four-chamber view and determined as the slope of aliasing velocity of early diastolic transmitral flow on the color M-mode using Aloka SSD-5500 with 5.0 MHz transducer. Aliasing velocity was set at 50-70% of the peak transmitral flow velocity. Peak transmitral flow velocities in early diastole (E) and during atrial contraction (A), and the ratio of early to late peak velocity (E/A) were obtained. Tei index was also measured for analysis of general left ventricular performance. Left ventricular mass index (LVMI) was obtained from conventional echo measurement. E, E/A, Tei index and LVMI were compared with FPV in healthy subjects. RESULTS: FPV obtained from all subjects ranged from 23.7 to 96.0 cm/s (61.3 +/- 13.6 cm/s). Normal value of FPV was less dependent on age, body size, heart rate and left ventricular dimension. In contrast, although there was no significant correlation between FPV and ejection fraction, statistically significant correlation was found between FPV, LVMI (P = 0.0008) and Tei index (P = 0.025). CONCLUSIONS: FPV is independent of age, body size and heart rate and is useful to assess left ventricular relaxation in children.

Open heart operation in a child with congenital heart disease and hereditary spherocytosis.

An 18-month-old girl with hereditary spherocytosis underwent closure of the ventricular septal defect, commissurotomy of the pulmonary valve, and patch angioplasty of the pulmonary trunk without previous splenectomy. No serious complications as a result of hemolysis occurred in the perioperative period. Open heart surgery can therefore be safely performed in young children with congenital heart disease and hereditary spherocytosis who have not previously undergone splenectomy.

Genetic analysis in patients with left ventricular noncompaction and evidence for genetic heterogeneity.

Left ventricular noncompaction (LVNC) is a cardiomyopathy characterized by numerous excessively trabeculations and deep intertrabecular recesses. This study was performed to investigate Japanese LVNC patients for disease-causing mutations in a series of selected candidate genes. DNA was isolated from the peripheral blood of 79 cases including 20 familial cases and 59 sporadic cases. DNA samples were screened for mutations in the genes encoding G4.5 (TAZ), alpha-dystrobrevin (DTNA), alpha1-syntrophin (SNTA1), FK506 Binding protein 1A (FKBP1A or FKPB12: FKBP1A), and LIM Domain Binding protein 3 (Cypher/ZASP: LDB3), using single-strand conformational polymorphism analysis and DNA sequencing. DNA variants were identified in 6 of the 79 cases, including four familial cases and two sporadic cases. A splice acceptor mutation of intron 8 in TAZ (IVS8-1G>C) was identified in one family with isolated LVNC, resulting in deletion of exon 9 from mRNA. In a sporadic case of isolated LVNC and Barth syndrome (BTHS), a 158insC in exon 2 of TAZ resulting in a frame-shift mutation was identified. A 1876G>A substitution changing an aspartic acid to asparagine (D626N) was identified in LDB3 in four members of two families with LVNC. A 163G>A polymorphism was identified in LDB3, which changed a valine to isoleucine (V55I) in one patient with isolated LVNC. In addition, in a family with nonisolated LVNC, a 362C>T mutation was identified in DTNA. LVNC, like other forms of inherited cardiomyopathy, is a genetically heterogeneous disease, associated with variable clinical symptoms and can be inherited as an autosomal or X-linked recessive disorder.