Tatsuya Hobara

Antiulcer mechanism of action of rebamipide, a novel antiulcer compound, on diethyldithiocarbamate-induced antral gastric ulcers in rats

The mechanism of the inhibitory action of rebamipide, a new mucosal protective drug, was studied using rats with diethyldithiocarbamate-induced gastric antral ulcers. Rebamipide reduced ulcer formation and inhibited the elevation in lipid peroxide concentration in the gastric mucosa. Rebamipide inhibited both luminol- and lucigenin-dependent chemiluminescence of neutrophils activated by formyl-methionyl-leucyl-phenylalanine. Rebamipide did not alter the reduction of cytochrome c induced by the xanthine-xanthine oxidase system or the NADPH-dependent microsomal lipid peroxidation in the liver. These findings suggest that rebamipide prevents diethyldithiocarbamate-induced gastric ulcer formation by inhibiting neutrophil activation.

Qat chewing and pesticides: A study of adverse health effects in people of the mountainous areas of Yemen

Chewing qat leaves, Cathula Edulis, is now a very common behaviour among the people of the mountainous areas of Yemen. For about the past 20 years, in tandem with national development, qat chewing has been rapidly expanding, and the use of chemical pesticides in qat production has been increasing. In this study, the adverse effects on human health of qat chewing combined with pesticide use were investigated. Results of interviews and questionnaires showed that chewers of qat grown with few or no chemical pesticides and chewers of qat grown with chemical pesticides have considerably different subjective symptoms. Chewers of qat produced in fields where chemical pesticides are used regularly have more symptoms than chewers of qat produced in fields where chemical pesticides are rarely or never used. Chewers of qat produced with more chemical pesticides, in particular, experience acute adverse effects on the digestive system and chronic adverse effects such as body weakness and nasal problems. Farmers who chew homemade qat on which they spread chemical pesticides by themselves may have the highest health risks regarding the combination of qat and pesticides. It is concluded that chewing qat grown with chemical pesticides causes considerable adverse health effects in human beings.

Role of active oxygen species in diethyldithiocarbamate-induced gastric ulcer in the rat.

Diethyldithiocarbamate, an inhibitor of Cu,Zn-superoxide dismutase, was recently found to be ulcerogenic in the rat stomach, and active oxygen species were found to be responsible for its ulcerogenicity. To clarify which active oxygen species play a role in ulcerogenesis, the effects of various scavengers and iron-chelators were studied. As superoxide dismutase and catalase reduced the ulcerogenesis induced by diethyldithiocarbamate, the superoxide radical and hydrogen peroxide were considered to play a pathogenic role in this ulcer model.

Validity of self-reported body mass index of Japanese children and adolescents

Background:  Self‐reported body mass index (BMI) has been widely used in epidemiological studies, but no study thus far has validated the self‐reported BMI of Japanese children and adolescents. The aim of the present study was to assess the accuracy of self‐reported BMI and its use for classification into weight categories.

Measuring Methods for Functional Reach Test: Comparison of 1-Arm Reach and 2-Arm Reach

UNLABELLED Kage H, Okuda M, Nakamura I, Kunitsugu I, Sugiyama S, Hobara T. Measuring methods for functional reach test: comparison of 1-arm reach and 2-arm reach. OBJECTIVES To investigate which functional reach test better reflects the center of pressure excursion, a 1-arm reach or a 2-arm reach, and to investigate the effect of trunk rotation on the reach distance in a 1-arm reach. In addition, we considered the influence of the individual variation at the starting position. DESIGN Descriptive study using a force platform and a 3-dimensional (3D) motion capture system. SETTING Motion analysis laboratory in a college setting. PARTICIPANTS Elderly volunteers (N=41; 15 men, 26 women; 71.8+/-5.2y). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES 3D coordinate data and the movement of the center of pressure. RESULTS The correlation between the reach distance and the center of pressure excursion was significantly higher (P<.05) for the 1-arm reach (r=.60, .72) compared with a 2-arm reach (r=.41, .55). In the case of the 1-arm reach, center of pressure excursion was a significant factor affecting reach distance (beta=.319, .470) in multivariate regression analysis, but trunk rotation was not (beta=.162, .095). When the reach distance was measured using the heel as a reference, the correlation was stronger. CONCLUSIONS To evaluate dynamic balance, a 1-arm reach, which better reflects center of pressure excursion, is more valid. It is meaningful to reduce the individual variation of the acromion at the starting position.

Effect of 1,1,1-Trichloroethane Inhalation on Heart Rate and Its Mechanism: A Role of Autonomic Nervous System

The response of heart rate to acute 1,1,1-trichloroethane (1,1,1-TCE) inhalation and its mechanism via the autonomic nervous system were studied in anesthetized dogs in acute inhalation experiments. Concentrations of 1,1,1-TCE in inspired air of 1.32 +/- 0.14% (mean +/- S.E.) increased heart rate, but 2.79 +/- 0.24% decreased heart rate. Opposite reactions of heart rate were observed when blood pressure decreased to 70-80 mm Hg following inhalation. Moreover, both tachycardia from relatively low concentrations and bradycardia from higher concentrations were blocked by pre-administration of adrenergic beta blocker, but were only slightly affected by vagotomy. It is suggested that both tachycardia and bradycardia following 1,1,1-TCE inhalation may be controlled by the sympathetic nervous system.

Neural Control of Blood Pressure following 1,1,1-Trichloroethane Inhalation: A Role of Sympathetic Nervous System

The effects of 1,1,1-trichloroethane (1,1,1-TCE) inhalation on arterial blood pressure and renal sympathetic nerve activity were investigated in anesthetized dogs. In acute inhalation experiments, the threshold concentration of 1,1,1-TCE required to produce a decrease in blood pressure was 0.4 to 0.5% in inspired air; moreover, a dose-response relationship between the decrease in blood pressure and 1,1,1-TCE concentration which exceeded the threshold level was observed. In addition, renal nerve activity increased and was associated with a slight decrease in blood pressure following inhalation of relatively low concentrations of 1,1,1-TCE. Following inhalation of relatively high concentrations of 1,1,1-TCE, however, renal nerve activity decreased and was accompanied by a marked decrease in blood pressure. Opposite reactions of renal nerve activity were observed when blood pressure decreased to 70-80 mm Hg following inhalation. It is suggested that systemic hypotension resulting from 1,1,1-TCE inhalation may be controlled by two different reactions of sympathetic nerve activity.

Association of serum carotenoids and tocopherols with atopic diseases in Japanese children and adolescents

Okuda M, Bando N, Terao J, Sasaki S, Sugiyama S, Kunitsugu I, Hobara T. Association of serum carotenoids and tocopherols with atopic diseases in Japanese children and adolescents. 
Pediatr Allergy Immunol 2010: 21: e705–e710.
© 2010 John Wiley & Sons A/S

Gastric mucosal injury induced by chloral hydrate

Abstract Gastric mucosal injury by chloral hydrate (CH) was investigated in the rat. Rats were injected with CH intraperitoneally or subcutaneously. After the CH injection, gastric ulcers appeared in the glandular stomach at 6 h and the ulcer index peaked in 12 h. The minimum dosage of CH to produce ulcers was 400 mg/ kg intraperitoneally and 600 mg/kg subcutaneously.

Acute effects of 1,1,1-trichloroethane, trichloroethylene, and toluene on the hematologic parameters in dogs

Mature cross-bred dogs were acutely exposed to 1,1,1-trichloroethane, trichloroethylene, and toluene. The changes in hematologic parameters, during and after exposure, are reported. A marked but temporary decrease in leukocytes was noted 30 min after the initation of exposure; no changes were observed in erythrocyte counts, hematocrit values, or thrombocytes counts with all three solvents. The decrease in the amount of neutrophils was particularly prominent. Based upon leukocyte differential counts, all types of leukocytes snowed a decrease. The decrease in leukocyte counts was the largest with exposure to trichloroethylene, followed by 1,1,1-trichloroethane, and toluene, respectively. A dose-response relationship was noted between exposure concentrations and decreased leukocyte counts,i.e., 1,1,1-trichloroethane and toluene from 200 to 700 ppm; trichloroethylene from 0 to 700 ppm.