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Aims/introduction Double C2 domain protein b (DOC2b), one of the synaptotagmins, has been shown to translocate to the plasma membrane, and to initiate membrane‐fusion processes of vesicles containing glucose transporter 4 proteins on insulin stimulation. However, the mechanism by which DOC2b is regulated remains unclear. Herein, we identified the upstream regulatory factors of DOC2b in insulin signal transduction. We also examined the role of DOC2b on systemic homeostasis using DOC2b knockout (KO) mice. Materials and Methods We first identified DOC2b binding proteins by immunoprecipitation and mutagenesis experiments. Then, DOC2b KO mice were generated by disrupting the first exon of the DOC2b gene. In addition to the histological examination, glucose metabolism was assessed by measuring parameters on glucose/insulin tolerance tests. Insulin‐stimulated glucose uptake was also measured using isolated soleus muscle and epididymal adipose tissue. Results We identified an isoform of atypical protein kinase C (protein kinase C iota) that can bind to DOC2b and phosphorylates one of the serine residues of DOC2b (S34). This phosphorylation is essential for DOC2b translocation. DOC2b KO mice showed insulin resistance and impaired oral glucose tolerance on insulin and glucose tolerance tests, respectively. Insulin‐stimulated glucose uptake was impaired in isolated soleus muscle and epididymal adipose tissues from DOC2b KO mice. Conclusions We propose a novel insulin signaling mechanism by which protein kinase C iota phosphorylates DOC2b, leading to glucose transporter 4 vesicle translocation, fusion and facilitation of glucose uptake in response to insulin. The present results also showed DOC2b to play important roles in systemic glucose homeostasis.

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

Quinolones are known to induce hypoglycemia, although there is no written report of garenoxacin-induced hypoglycemia. We herein report a case of garenoxacin-induced hypoglycemia in a patient not taking hypoglycemic drugs. An 89-year-old Japanese woman with type 2 diabetes and chronic renal insufficiency requiring hemodialysis was admitted to the emergency department in a comatose state. Her serum glucose measured 1 mg/dL on arrival. The patient had not taken any hypoglycemic drugs recently and had never experienced a hypoglycemic episode. She had received a four-day course of garenoxacin treatment before the emergency admission. Clinicians should therefore recognize the potential risk of hypoglycemia during garenoxacin therapy.

Loss of functional beta cells results in a gradual progression of insulin insufficiency in Wolfram syndrome caused by recessive WFS1 mutations. However, beta cell dysfunction in Wolfram syndrome has yet to be fully characterised, and there are also no specific treatment recommendations. In this study, we aimed to characterise beta cell secretory defects and to examine the potential effects of a glucagon-like peptide-1 (GLP-1) receptor agonist on diabetes in Wolfram syndrome. Insulin secretory function was assessed by the pancreatic perfusion method in mice used as a model of Wolfram syndrome. In addition, granule dynamics in living beta cells were examined using total internal reflection fluorescence microscopy. Acute and chronic effects of exendin-4 (Ex-4) on glucose tolerance and insulin secretion were examined in young Wfs1−/− mice without hyperglycaemia. Molecular events associated with Ex-4 treatment were investigated using pancreatic sections and isolated islets. In addition, we retrospectively observed a woman with Wolfram syndrome who had been treated with liraglutide for 24 weeks. Treatment with liraglutide ameliorated our patient’s glycaemic control and resulted in a 20% reduction of daily insulin dose along with an off-drug elevation of fasting C-peptide immunoreactivity. Glucose-stimulated first-phase insulin secretion and potassium-stimulated insulin secretion decreased by 53% and 59%, respectively, in perfused pancreases of 10-week-old Wfs1−/− mice compared with wild-type (WT) mice. The number of insulin granule fusion events in the first phase decreased by 41% in Wfs1−/− beta cells compared with WT beta cells. Perfusion with Ex-4 increased insulin release in the first and second phases by 3.9-fold and 5.6-fold, respectively, in Wfs1−/− mice compared with perfusion with saline as a control. The physiological relevance of the effects of Ex-4 was shown by the fact that a single administration potentiated glucose-stimulated insulin secretion and improved glucose tolerance in Wfs1−/− mice. Four weeks of administration of Ex-4 resulted in an off-drug amelioration of glucose excursions after glucose loading in Wfs1−/− mice, with insulin secretory dynamics that were indistinguishable from those in WT mice, despite the fact that there was no alteration in beta cell mass. In association with the functional improvements, Ex-4 treatment reversed the increases in phosphorylated eukaryotic initiation factor (EIF2α) and thioredoxin interacting protein (TXNIP), and the decrease in phosphorylated AMP-activated kinase (AMPK), in the beta cells of the Wfs1−/− mice. Furthermore, Ex-4 treatment modulated the transcription of oxidative and endoplasmic reticulum stress-related markers in isolated islets, implying that it was able to mitigate the cellular stresses resulting from Wfs1 deficiency. Our study provides deeper insights into the pathophysiology of beta cell dysfunction caused by WFS1 deficiency and implies that activation of the GLP-1 receptor signal may alleviate insulin insufficiency and aid glycaemic control in Wolfram syndrome.

Aryl hydrocarbon receptor nuclear translocator (ARNT)/hypoxia inducible factor-1β (HIF-1β) has emerged as a potential determinant of pancreatic β-cell dysfunction and type 2 diabetes in humans. An 82% reduction in Arnt expression was observed in islets from type 2 diabetic donors as compared to non-diabetic donors. However, few regulators of Arnt expression have been identified. Meanwhile, disruption of the clock components CLOCK and BMAL1 is known to result in hypoinsulinemia and diabetes, but the molecular details remain unclear. In this study, we identified a novel molecular connection between Arnt and two clock-controlled output genes, albumin D-element binding protein (Dbp) and E4 binding protein 4 (E4bp4). By conducting gene expression studies using the islets of Wfs1(-/-) A(y)/a mice that develop severe diabetes due to β-cell apoptosis, we demonstrated clock-related gene expressions to be altered in the diabetic mice. Dbp mRNA decreased by 50%, E4bp4 mRNA increased by 50%, and Arnt mRNA decreased by 30% at Zeitgever Time (ZT) 12. Mouse pancreatic islets exhibited oscillations of clock gene expressions. E4BP4, a D-box negative regulator, oscillated anti-phase to DBP, a D-box positive regulator. We also found low-amplitude circadian expression of Arnt mRNA, which peaked at ZT4. Over-expression of DBP raised both mRNA and protein levels of ARNT in HEK293 and MIN6 cell lines. Arnt promoter-driven luciferase reporter assay in MIN6 cells revealed that DBP increased Arnt promoter activity by 2.5-fold and that E4BP4 competitively inhibited its activation. In addition, on ChIP assay, DBP and E4BP4 directly bound to D-box elements within the Arnt promoter in MIN6 cells. These results suggest that in mouse pancreatic islets mRNA expression of Arnt fluctuates significantly in a circadian manner and that the down-regulation of Dbp and up-regulation E4bp4 contribute to direct suppression of Arnt expression in diabetes.

Laser Doppler Velocimetry (LDV) measurements in a 90 degree elbow of which the curvature radius coincides with its inner diameter were examined for the cases of inflow from a long pipe, short pipe and swirl generator. Ensemble averaged flow distribution at the Reynolds number of 320000 based on the inner pipe diameter and bulk velocity shows that shortening the upstream pipe length to 4.9D from 10D induces the flow separation downstream of the elbow. Detailed observation suggests that shortening upstream pipe weakens the Prandtl's secondary flow of the first kind. Our swirl generator induced a swirling inflow with the non-dimensional angular momentum of 0.12 based on the inner pipe diameter and bulk velocity. The circumferential velocity distribution formed a shape like a Rankine combined vortex at the elbow inlet, and the accelerated axial velocity was observed at the vortex center. The axial velocity distribution however was found to be almost the same as that of the non-swirl inflow case in the latter half of the elbow. Frequency analyses showed that the Strouhal number by vortex shedding from the boundary layer occurring at the inner side of the elbow become 0.5, except for 0.6 in the case of the long pipe. The change of the Strouhal number is probably related with the boundary layer width and the local flow velocity.

LDV measurements in a 90 degree elbow, of which curvature radius coincides with the diameter have been conducted for cases of developed inflow, undeveloped inflow, swirling inflow, and deflected inflow that became faster at the inside. This paper especially focuses on a result of the deflected inflow, comparing with a result of the undeveloped inflow. The result shows that the deflected inflow reinforces a convex velocity distribution occurring near the curvature inside in the downstream region, concluding that the deflected inflow promotes the secondary flow of Prandtl's first kind in the elbow. Frequency analyses of axial flow fluctuations show that the dominant frequency can be seen in the downstream of the elbow even in the deflected inflow case. However its Strouhal number increases to 0.6 from 0.5, that is for the short pipe case. Results of frequency analyses are also shown for other cases that we have been examined. Dominant Strouhal numbers in most of the cases become 0.5, except for 0.6 in cases of the developed and deflected inflow. This frequency shift might be related with the boundary layer size and the local flow velocity, since the corresponding fluctuation is caused by vortex shedding from the boundary layer at the elbow inside.

Wolfram syndrome is an autosomal recessive disorder characterized by juvenile-onset insulin-dependent diabetes mellitus and optic atrophy. The gene responsible for the syndrome (WFS1) encodes an endoplasmic reticulum (ER) resident transmembrane protein. The Wfs1-null mouse exhibits progressive insulin deficiency causing diabetes. Previous work suggested that the function of the WFS1 protein is connected to unfolded protein response and to intracellular Ca(2+) homeostasis. However, its precise molecular function in pancreatic β-cells remains elusive. In our present study, immunofluorescent and electron-microscopic analyses revealed that WFS1 localizes not only to ER but also to secretory granules in pancreatic β-cells. Intragranular acidification was assessed by measuring intracellular fluorescence intensity raised by the acidotrophic agent, 3-[2,4-dinitroanilino]-3'-amino-N-methyldipropyramine. Compared with wild-type β-cells, there was a 32% reduction in the intensity in WFS1-deficient β-cells, indicating the impairment of granular acidification. This phenotype may, at least partly, account for the evidence that Wfs1-null islets have impaired proinsulin processing, resulting in an increased circulating proinsulin level. Morphometric analysis using electron microscopy evidenced that the density of secretory granules attached to the plasma membrane was significantly reduced in Wfs1-null β-cells relative to that in wild-type β-cells. This may be relevant to the recent finding that granular acidification is required for the priming of secretory granules preceding exocytosis and may partly explain the fact that glucose-induced insulin secretion is profoundly impaired in young prediabetic Wfs1-null mice. These results thus provide new insights into the molecular mechanisms of β-cell dysfunction in patients with Wolfram syndrome.

56歳，女性が３年前に胃mucosa-associated lymphoid tissue (MALT) リンパ腫と診断された．Helicobacter pylori (HP) 陽性であり除菌を施行されたが不成功でありその後は経過観察されていた．２年後に右眼瞼腫瘤を指摘され生検にてMALTリンパ腫と診断され，胃ではMALTリンパ腫の増大，肺の浸潤影を認めた．胃MALTリンパ腫の生検では瀰漫性のリンパ球の浸潤および一部には形質細胞への分化を認めた．血清中の単クローン性IgM，λの増加，骨髄では形質細胞の浸潤を認めた．HPに対して２次除菌を行い成功した．次いでrituximabとcladribine (2-chlorodeoxyadenosine，2CdA) の併用，R-2CdA療法を４コース施行しMALTリンパ腫は縮小しIgMは減少したが正常値にはならなかったのでCHOP療法２コースを追加しIgMはさらに減少した．MALTリンパ腫における長期間にわたる多様な臨床経過に対し注意深い観察および必要な時に適切な治療を行うことが必要である．

72歳，男性が発熱，腰痛，全身倦怠感を訴えて来院した．患者は６年前に他院にて瀰漫性大細胞型B細胞性リンパ腫と診断され化学療法にて寛解に導入されたが，５年後リンパ腫は再発し再度の化学療法にて部分寛解に導入された．当院初診時の検査所見では貧血，LDH，sIL-2Rの著増，D-dimerの増加を認めた．骨髄穿刺，骨髄生検にて壊死細胞のみ採取された．MRIでは脊椎椎体はT1で巣状にlow intensityを呈した．感染症は否定的であった．これらの症状および検査所見は骨髄壊死に特徴的でありリンパ腫の再燃により合併したと考えられた．CHOP,R-CHOP,THP-COPなどの化学療法を開始したところ一時的に血液像は改善し，骨髄穿刺は可能になり造血細胞も少数認められた．しかし最終的には効果はなく約３ヵ月後に多臓器不全にて死亡した．剖検ではリンパ腫の進展，リンパ腫細胞の骨髄への浸潤および多発性の骨髄壊死が認められた．骨髄壊死の発症の機序としてはリンパ腫細胞の骨髄浸潤，DIC,炎症性サイトカインなどの関与が示唆された．

自己免疫性溶血性貧血において副腎皮質ステロイドにて治療中難治性のクリプトコッカス髄膜炎を発症した稀な症例を報告する．7年前より自己免疫性溶血性貧血にて副腎皮質ステロイド投与にて治療中の48歳の男性患者が4ヵ月前に頭痛，難聴，嘔気，嘔吐などを訴えクリプトコッカス髄膜炎を発症した．後に貧血の増悪のためにショック状態になり当科に紹介された．この間に視力障害，全盲，を合併した．貧血はm-PSLによるパルス療法により改善した．クリプトコッカス髄膜炎に対してはAMPH-B（注射用dAMPH-B，リポゾーム化剤，L-AMB），5-FC，アゾール剤であるFLCZおよびVRCZなどの投与により髄膜炎症状は消失した．抗真菌剤を1年半投与し，髄液中のクリプトコッカス抗原量は著明に減少したが陰性化せずまた墨汁染色ではクリプトコッカスの数は減少したが未だ完全には消失しておらず難治性であり視力障害，難聴は残存した．

Recently, incretin-based therapies have become available for patients with type 2 diabetes in Japan. Sitagliptin is one of several DPP-4 inhibitors. After an OGTT, active endogenous GLP-1 concentrations are increased about twofold by sitagliptin. In clinical trials, sitagliptin was shown to be effective in monotherapy and in combination with other oral agents. Hypoglycemic events were not increased in monotherapy. However in Japan, severe hypoglycemic events have been reported especially in older patients with high dose of sulfonylurea. The long-term effectiveness needs to be evaluated in Japanese patients with type 2 diabetes.

A patient with acute promyelocytic leukemia(APL)treated with all-trans retinoic acid(ATRA)and chemotherapy for remission induction developed marked thrombocytosis after bone marrow recovery. Thrombocytosis also occurred after post remission chemotherapies, although the degree of thrombocytosis gradually decreased. During thrombocytosis, plasma levels of interleukin-6(IL-6)were elevated while those of thrombopoietin(TPO)were not elevated. However, the plasma level of TPO was markedly elevated at the nadir after post remission chemotherapy. These findings suggest that in APL patients, thrombocytosis after treatment with ATRA and or chemotherapy may be caused by increased plasma levels of both of IL-6 and TPO.

A 68-year-old female complained of anemia and bone pain. Monoclonal increase of plasma IgA, lambda-type was observed, and immature plasma cells were detected in the bone marrow. These plasma cells showed intermediate differentiation on CD38 gating flow cytometry. Chromosomal analysis demonstrated complex abnormalities including repeats and translocation, t(8;22)(q24;q11.2) by G-banding, and breakpoint down stream of 3'c-MYC on fluorescence in situ hybridization. Multiple myeloma with variant type translocation was diagnosed. Treatment with continuous infusion of dexamethasone and oral administration of thalidomide effectively decreased IgA, plasma cells and chromosomal abnormality, facilitating complete remission.

The reaction of phenols with benzyltrimethylammonium dichloroiodate(1–) in dichloromethane-methanol in the presence of CaCO3 or NaHCO3 for several hours at room temperature gave iodophenols in good yields.

The reaction of aromatic amines with benzyltrimethylammonium tribromide in dichloromethane–methanol containing calcium carbonate powder for 0.5 h at room temperature gave bromo-substituted aromatic amines in good yields.