第IX(a)因子および第X因子に対する二重特異性抗体であるエミシズマブはin vitroで第XI因子欠乏血漿における凝固機能を増強する

Essentials Emicizumab mimics factor (F)VIIIa cofactor function, augments the intrinsic tenase activity. We assessed the emicizumab-driven hemostatic function in FXI-deficient plasmas. Emicizumab improved the coagulation potentials in severe FXI-deficient plasma. Emicizumab may provide a possibility for clinical application in patients with FXI deficiency. SUMMARY: Background Patients with factor (F)XI deficiency commonly present with markedly prolonged activated partial thromboplastin times (APTT), although bleeding phenotypes are heterogeneous. Emicizumab, a bispecific monoclonal antibody to FIX/FIXa and FX/FXa, mimics FVIIIa cofactor function on phospholipid (PL) surfaces. Antibody reactions were designed, therefore, to augment mechanisms during the propagation phase of blood coagulation. Aim To assess emicizumab-driven hemostatic function in FXI-deficient plasmas. Methods and Results Standard ellagic acid (Elg)/PL-based APTTs of different FXI-deficient plasmas (n = 13; FXI activity, < 1 IU dl-1 ) were markedly shortened dose dependently by the presence of emicizumab. To further analyze the effects of emicizumab, clot waveform analysis (CWA) in FXI-deficient plasmas with emicizumab, triggered by tissue factor (TF)/Elg demonstrated improvements in both clot times, reflecting the initiation phase, and coagulation velocity, which represents the propagation phase. Emicizumab also enhanced the TF/Elg-triggered thrombin generation in FXI-deficient plasmas dose-dependently although the degree of enhancement varied in individual cases. Thrombin generation with either FVII-deficient plasma or FIX-deficient plasma treated with anti-FXI antibody showed little or no increase by the co-presence of emicizumab, suggesting that the accelerated thrombin generation in FXI-deficient plasmas by emicizumab should depend on the FIXa-involved coagulation propagation initially triggered by FVIIa/TF. The ex vivo addition of emicizumab to whole blood from three patients with severe FXI deficiency demonstrated modest, dose-dependent improvements in Ca2+ -triggered thromboelastograms (NATEM mode). Conclusion Emicizumab appeared to improve coagulation function in severe FXI-deficient plasma, and might provide possibilities for clinical application in patients with FXI deficiency.博士（医学）・乙第1427号・平成31年3月15日© 2018 International Society on Thrombosis and HaemostasisThis is the pre-peer reviewed version of the following article: [https://onlinelibrary.wiley.com/doi/full/10.1111/jth.14334], which has been published in final form at [http://dx.doi.org/10.1111/jth.14334]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions

A Comparison of Physical vs. Nonphysical Wedge Modalities in Radiotherapy

This chapter discusses the clinical application and implementation of wedge techniques in radiation therapy. Coverage of the target region with a curative dose is critical for treating several cancer types; to that end, wedge filters are commonly used to improve dose uniformity to the target volume. Initially, wedges designed for this purpose were physical and were made of high-density materials such as lead or steel. Subsequently, nonphysical wedges were introduced; these improved the dose uniformity using computer systems in lieu of physical materials. As wedge systems evolve, however, they each continue to have their advantages and disadvantages. When using physical wedges, it is difficult to control the generation of secondary radiation resulting from the collision of the radiation beam with the wedge body; conversely, nonphysical wedges do not create any secondary radiation because there is no physical interference with the beam. On the other hand, nonphysical wedges are less suitable for treating moving tumors, such as those in the lung, and physical wedges have better dose coverage to the target volume than nonphysical wedges. This chapter aims to guide decision-making regarding the choice of wedge types in various clinical situations

Image-based evaluation of contraction–relaxation kinetics of human-induced pluripotent stem cell-derived cardiomyocytes: Correlation and complementarity with extracellular electrophysiology

AbstractIn this study, we used high-speed video microscopy with motion vector analysis to investigate the contractile characteristics of hiPS-CM monolayer, in addition to further characterizing the motion with extracellular field potential (FP), traction force and the Ca2+ transient. Results of our traction force microscopy demonstrated that the force development of hiPS-CMs correlated well with the cellular deformation detected by the video microscopy with motion vector analysis. In the presence of verapamil and isoproterenol, contractile motion of hiPS-CMs showed alteration in accordance with the changes in fluorescence peak of the Ca2+ transient, i.e., upstroke, decay, amplitude and full-width at half-maximum. Simultaneously recorded hiPS-CM motion and FP showed that there was a linear correlation between changes in the motion and field potential duration in response to verapamil (30–150nM), isoproterenol (0.1–10μM) and E-4031 (10–50nM). In addition, tetrodotoxin (3–30μM)-induced delay of sodium current was corresponded with the delay of the contraction onset of hiPS-CMs. These results indicate that the electrophysiological and functional behaviors of hiPS-CMs are quantitatively reflected in the contractile motion detected by this image-based technique. In the presence of 100nM E-4031, the occurrence of early after-depolarization-like negative deflection in FP was also detected in the hiPS-CM motion as a characteristic two-step relaxation pattern. These findings offer insights into the interpretation of the motion kinetics of the hiPS-CMs, and are relevant for understanding electrical and mechanical relationship in hiPS-CMs

Crucial role of nitric oxide synthases system in endothelium-dependent hyperpolarization in mice

The endothelium plays an important role in maintaining vascular homeostasis by synthesizing and releasing several relaxing factors, such as prostacyclin, nitric oxide (NO), and endothelium-derived hyperpolarizing factor (EDHF). We have previously demonstrated in animals and humans that endothelium-derived hydrogen peroxide (H2O2) is an EDHF that is produced in part by endothelial NO synthase (eNOS). In this study, we show that genetic disruption of all three NOS isoforms (neuronal [nNOS], inducible [iNOS], and endothelial [eNOS]) abolishes EDHF responses in mice. The contribution of the NOS system to EDHF-mediated responses was examined in eNOS−/−, n/eNOS−/−, and n/i/eNOS−/− mice. EDHF-mediated relaxation and hyperpolarization in response to acetylcholine of mesenteric arteries were progressively reduced as the number of disrupted NOS genes increased, whereas vascular smooth muscle function was preserved. Loss of eNOS expression alone was compensated for by other NOS genes, and endothelial cell production of H2O2 and EDHF-mediated responses were completely absent in n/i/eNOS−/− mice, even after antihypertensive treatment with hydralazine. NOS uncoupling was not involved, as modulation of tetrahydrobiopterin (BH4) synthesis had no effect on EDHF-mediated relaxation, and the BH4/dihydrobiopterin (BH2) ratio was comparable in mesenteric arteries and the aorta. These results provide the first evidence that EDHF-mediated responses are dependent on the NOSs system in mouse mesenteric arteries

Activation of AMPK-Regulated CRH Neurons in the PVH is Sufficient and Necessary to Induce Dietary Preference for Carbohydrate over Fat

Food selection is essential for metabolic homeostasis and is influenced by nutritional state, food palatability, and social factors such as stress. However, the mechanism responsible for selection between a high-carbohydrate diet (HCD) and a high-fat diet (HFD) remains unknown. Here, we show that activation of a subset of corticotropin-releasing hormone (CRH)-positive neurons in the rostral region of the paraventricular hypothalamus (PVH) induces selection of an HCD over an HFD in mice during refeeding after fasting, resulting in a rapid recovery from the change in ketone metabolism. These neurons manifest activation of AMP-activated protein kinase (AMPK) during food deprivation, and this activation is necessary and sufficient for selection of an HCD over an HFD. Furthermore, this effect is mediated by carnitine palmitoyltransferase 1c (CPT1c). Thus, our results identify the specific neurons and intracellular signaling pathway responsible for regulation of the complex behavior of selection between an HCD and an HFD

Genome-Wide Analysis of Acute Endurance Exercise-Induced Translational Regulation in Mouse Skeletal Muscle

<div><p>Exercise dynamically changes skeletal muscle protein synthesis to respond and adapt to the external and internal stimuli. Many studies have focused on overall protein synthesis to understand how exercise regulates the muscular adaptation. However, despite the probability that each gene transcript may have its own unique translational characteristics and would be differentially regulated at translational level, little attention has been paid to how exercise affects translational regulation of individual genes at a genome-wide scale. Here, we conducted a genome-wide translational analysis using ribosome profiling to investigate the effect of a single bout of treadmill running (20 m/min for 60 min) on mouse gastrocnemius. Global translational profiles largely differed from those in transcription even at a basal resting condition as well as immediately after exercise. As for individual gene, Slc25a25 (Solute carrier family 25, member 25), localized in mitochondrial inner membrane and maintaining ATP homeostasis and endurance performance, showed significant up-regulation at translational level. However, multiple regression analysis suggests that Slc25a25 protein degradation may also have a role in mediating Slc25a25 protein abundance in the basal and early stages after acute endurance exercise.</p></div

Magnetic Resonance Imaging Diagnosis of Dandy-Walker-Like Syndrome in a Wire-Haired Miniature Dachshund

A 12-week-old female Wire-haired miniature dachshund presented with non-progressive ataxia and hypermetria. Due to the animal’s clinical history and symptoms, cerebellar malformations were suspected. Computed tomography (CT) and magnetic resonance imaging (MRI) detected bilateral ventriculomegaly, dorsal displacement of the cerebellar tentorium, a defect in the cerebellar tentorium and a large fluid-filled cystic structure that occupied the regions where the cerebellar vermis and occipital lobes are normally located. The abovementioned cystic structure and the defect in the cerebellar tentorium were comparable to those seen in humans with Dandy-Walker syndrome. However, the presence of the cystic structure in the occipital lobe region was unique to the present case. During necropsy, the MRI findings were confirmed, but the etiology of the condition was not determined

Slower clozapine titration is associated with delayed onset of clozapine-induced fever among Japanese patients with schizophrenia

Abstract Clozapine-induced fever marks the beginning of its inflammatory and potentially life-threatening adverse effects, such as myocarditis. We retrospectively analyzed the correlation between clozapine titration rate and fever onset date in 254 Japanese patients, including 55 with treatment-resistant schizophrenia who developed clozapine-induced fever. Pearson’s product-moment correlation indicated a significant delay in the fever onset date with slower titration. Most fever onset cases occurred within 4 weeks, even with slow titration. Therefore, clinicians should remain vigilant in monitoring clozapine-induced fever within 4 weeks of clozapine initiation, regardless of the titration rate

A new experimental model of ATP-sensitive K+ channel-independent insulinotropic action of glucose: a permissive role of cAMP for triggering of insulin release from rat pancreatic beta-cells

信州大学博士（医学）・学位論文・平成24年3月31日授与（甲第936号）・武井 真大In pancreatic beta-cells, glucose metabolism leads to closure of ATP sensitive K+ channels (K-ATP channel) and Ca2+ influx, which is regarded as a required step for triggering of insulin release. Here, we demonstrate that glucose triggers rapid insulin release independent from its action on K-ATP channels given the cellular cAMP is elevated. We measured insulin release from rat pancreatic islets by static and perifusion experiments. Changes in cytosolic free Ca2+ concentration ([Ca2+](i)) were monitored using fura-2 loaded rat pancreatic beta-cells. Glucose-induced insulin release was abolished when Ca2+ influx was inhibited by a combination of 250 mu M diazoxide, an opener of K-ATP channel, and 10 mu M nifedipine, a blocker of L-type voltage-dependent Ca2+ channels. However, with both nifedipine and diazoxide, glucose induced a 5-fold increase in insulin release in the presence of 10 mu M forskolin, an activator of adenylyl cyclase. In the presence of diazoxide, nifedipine, and forskolin, 22 mM glucose sharply increased the rate of insulin release within 2 min which peaked at 6 min: this was followed by a further gradual increase in insulin release. In contrast, it lowered [Ca2+](i) with a nadir at 2-3 min followed by a gradual increase in [Ca2+](i). The glucose effect was mimicked by 20 mM alpha-ketoisocaproic acid, a mitochondrial fuel, and it was nullified by 2 mM sodium azide, an inhibitor of mitochondrial electron transport. Cerulenin, an inhibitor of protein acylation, decreased the glucose effect. In conclusion, a rise in [Ca2+](i) through voltage-dependent Ca2+ channels is not mandatory for glucose-induced triggering of insulin release.ArticleENDOCRINE JOURNAL. 60(5):599-607 (2013)journal articl

Durability of Combustion Chamber Sliding Parts of the Main Engine of a Fishery Training Ship

漁業練習船における主機関及び発電機関の17年間の使用実績,機関性能の経年摩耗状態を調査分析したところ,次のことが明らかになった。1)機関主要箇所の予測される摩耗量が船の耐用期間中に使用限度を超えるものは見当たらなかった。既往と同条件下における,使用時間と摩耗量の関係について予測回帰式を求め,所要交換部品の調達時期の予測を可能とした。2)主機関のシリンダライナは頂部の摩耗率が大きく,摩耗状況から漁船特有の腐食摩耗と推定できる。3)主機関ピストンリングの摩耗率はA重油使用機関としては高い値を示していた。これは低負荷長時間運転,並びに観測時及び漁業操業時における主機関の停止による機関冷却により,硫化物の生成による腐食摩耗のためと推察される