Enhancing effects of salicylate on tonic and phasic block of Na+ channels by class 1 antiarrhythmic agents in the ventricular myocytes and the guinea pig papillary muscle

AbstractObjective: To study the interaction between salicylate and class 1 antiarrhythmic agents. Methods: The effects of salicylate on class 1 antiarrhythmic agent-induced tonic and phasic block of the Na+ current (INa) of ventricular myocytes and the upstroke velocity of the action potential (Vmax) of papillary muscles were examined by both the patch clamp technique and conventional microelectrode techniques. Results: Salicylate enhanced quinidine-induced tonic and phasic block of INa at a holding potential of −100 mV but not at a holding potential of −140 mV; this enhancement was accompanied by a shift of the h∞ curve in the presence of quinidine in a further hyperpolarized direction, although salicylate alone did not affect INa. Salicylate enhanced the tonic and phasic block of Vmax induced by quinidine, aprindine and disopyramide but had little effect on that induced by procainamide or mexiletine; the enhancing effects were related to the liposolubility of the drugs. Conclusions: Salicylate enhanced tonic and phasic block of Na+ channels induced by class 1 highly liposoluble antiarrhythmic agents. Based on the modulated receptor hypothesis, it is probable that this enhancement was mediated by an increase in the affinity of Na+ channel blockers with high lipid solubility to the inactivated state channels

小学生がうま味の相乗効果を学ぶための味覚授業の実施

The purpose of this study was to assess whether elementary school children were able to learn the synergistic effects of umami flavor through the implementation of a sense of taste class for them. The sense of taste class held for 182 elementary school children (aged, 10–11 years old in Kyoto city). The subjects assessed three types of broths: dried bonito (DB), kombu kelp (KK), and dried bonito-kombu kelp (DB-KK). The subject evaluated the broth for several factors: tastiness, umami flavor, aroma, fishy smell. In addition, children were asked to write their own comments about what they had learned or noticed. A total of 147 healthy subjects were analyzed.The results of the sensory evaluation showed that the children sensed umami flavor and tastiness more significantly in DB-KK broth than in KK broth. They also evaluated the DB broth and DB-KK broth to have a significantly better aroma than KK broth (both at p<0.05). The analysis of the comment showed that 11 children (7.5%) wrote about their understanding of the fundamental taste umami, and 31 children (21.1%) wrote about understanding the synergistic effect of umami flavor. These results suggest that the implementation of the sense of taste class is effective to learn the synergistic effects of umami flavor.論

Phospholipase D Family Member 4, a Transmembrane Glycoprotein with No Phospholipase D Activity, Expression in Spleen and Early Postnatal Microglia

BACKGROUND: Phospholipase D (PLD) catalyzes conversion of phosphatidylcholine into choline and phosphatidic acid, leading to a variety of intracellular signal transduction events. Two classical PLDs, PLD1 and PLD2, contain phosphatidylinositide-binding PX and PH domains and two conserved His-x-Lys-(x)(4)-Asp (HKD) motifs, which are critical for PLD activity. PLD4 officially belongs to the PLD family, because it possesses two HKD motifs. However, it lacks PX and PH domains and has a putative transmembrane domain instead. Nevertheless, little is known regarding expression, structure, and function of PLD4. METHODOLOGY/PRINCIPAL FINDINGS: PLD4 was analyzed in terms of expression, structure, and function. Expression was analyzed in developing mouse brains and non-neuronal tissues using microarray, in situ hybridization, immunohistochemistry, and immunocytochemistry. Structure was evaluated using bioinformatics analysis of protein domains, biochemical analyses of transmembrane property, and enzymatic deglycosylation. PLD activity was examined by choline release and transphosphatidylation assays. Results demonstrated low to modest, but characteristic, PLD4 mRNA expression in a subset of cells preferentially localized around white matter regions, including the corpus callosum and cerebellar white matter, during the first postnatal week. These PLD4 mRNA-expressing cells were identified as Iba1-positive microglia. In non-neuronal tissues, PLD4 mRNA expression was widespread, but predominantly distributed in the spleen. Intense PLD4 expression was detected around the marginal zone of the splenic red pulp, and splenic PLD4 protein recovered from subcellular membrane fractions was highly N-glycosylated. PLD4 was heterologously expressed in cell lines and localized in the endoplasmic reticulum and Golgi apparatus. Moreover, heterologously expressed PLD4 proteins did not exhibit PLD enzymatic activity. CONCLUSIONS/SIGNIFICANCE: Results showed that PLD4 is a non-PLD, HKD motif-carrying, transmembrane glycoprotein localized in the endoplasmic reticulum and Golgi apparatus. The spatiotemporally restricted expression patterns suggested that PLD4 might play a role in common function(s) among microglia during early postnatal brain development and splenic marginal zone cells

学生の衛生管理習得度に及ぼすオリジナルビデオ教材と大量調理実習の実施回数の効果の検討

本研究では，管理栄養士専攻学生の大量調理実習において，クラウド型授業支援システム（manaba course）を活用してビデオ教材の動画を配信した受講生（ビデオ教材-manaba配信群）とビデオ教材を導入していない受講生（ビデオ教材なし群）の衛生管理習得度を比較した。大量調理7回目のビデオ教材-manaba配信群（81人）とビデオ教材なし群（97人）の習得度を比較したところ，ビデオ教材-manaba配信群がビデオ教材なし群よりも「指導できる」・「一人で実践できる」と回答した者の割合が高かった項目は「水質検査」のみであった。一方，ビデオ教材が実習に役立つと回答した者は98%であった。さらに，衛生管理習得度に対する大量調理の実施回数の効果を検討した。大量調理を伴う実習が0，2，4，7回目（大量調理0回，2回，4回，7回）の際に習得度を調査した。大量調理7回目で「指導できる」・「一人で実践できる」と回答した学生が過半数を超えたのは3項目であり，衛生管理習得度が高い項目は実習での作業経験者の割合も高かった。これらの結果より，大量調理実習における衛生管理習得度の向上には，学生が実際に衛生管理に関する作業を経験することが重要であると考えられた。また，ビデオ教材の活用は，学生自らの経験には及ばないが，衛生管理に関する知識を補い，実習の予習や復習に役立つ可能性が高いと考えられた。研究ノー

Genome evolution in the allotetraploid frog Xenopus laevis

To explore the origins and consequences of tetraploidy in the African clawed frog, we sequenced the Xenopus laevis genome and compared it to the related diploid X. tropicalis genome. We characterize the allotetraploid origin of X. laevis by partitioning its genome into two homoeologous subgenomes, marked by distinct families of ???fossil??? transposable elements. On the basis of the activity of these elements and the age of hundreds of unitary pseudogenes, we estimate that the two diploid progenitor species diverged around 34 million years ago (Ma) and combined to form an allotetraploid around 17-18 Ma. More than 56% of all genes were retained in two homoeologous copies. Protein function, gene expression, and the amount of conserved flanking sequence all correlate with retention rates. The subgenomes have evolved asymmetrically, with one chromosome set more often preserving the ancestral state and the other experiencing more gene loss, deletion, rearrangement, and reduced gene expression.ope

Central Administration of Glucose Modifies Brain Amino Acid Metabolism in Neonatal Chicks

Intracerebroventricular injection of glucose can induce a sedative effect in chicks under social isolation stress. In addition, central injection of glucose improves memory formation in chicks in the passive avoidance task. In the present study, we confirmed that intracerebroventricular injection of glucose modified aspartate, arginine, glutamate, β-alanine, glycine and serine-ortho-phosphate levels of the telencephalon which are known to induce sedative effects in chicks. In addition, not only glutamate in the telenephalon, one of whose receptors is involved in the formation of memory in chicks, but also its metabolite glutamine was affected. These results suggest that some types of amino acid metabolism may be linked to the functions of glucose in the brain, attenuate the stress response and improve memory formation in chicks

Central Injection of Glucose Modifies Behavior, Amino Acid and Monoamine Metabolism in Neonatal Chicks under Acute Stressful Conditions

The effect of intracerebroventricular (i.c.v.) injection of a wide range of glucose concentrations on the behavioral response, central amino acid and monoamine contents was investigated in chicks exposed to a social isolation stressful condition. The chicks were given an i.c.v. injection of 0.21, 0.42, 0.84, and 1.68 μmol of D-glucose, and then behavioral changes were observed over 10 min. The behavioral stress response was dose-dependently decreased and calm behavior was increased by i.c.v. administration of glucose. In the diencephalon, glutamine was positively correlated, whereas glycine was negatively correlated with the dose of glucose. In the telencephalon, the dopamine metabolite and dopamine turnover rates were positively correlated, whereas dopamine was negatively correlated with doses of glucose. In the plasma, isoleucine and hydroxyproline were positively correlated with the dose of glucose, and several amino acids were also influenced by glucose levels.These results suggest that the possible pathways of the sedative effect of glucose include: (1) amino acids synthesized from injected glucose, which can induce the sedative and/or hypnotic effects; (2) amino acids modified by injected glucose transported in the brain from the peripheral tissues; and (3) injected glucose-induced decreases in brain dopamine levels. In conclusion, these changes induced by central glucose interact and induce the sedative effect in neonatal chicks