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T Arisawa

Publications and source records attributed to T Arisawa.

At least 127 records · Page 7Linked to original sources
PubMed1991

[The effect of a new immunosuppressive agent, FK-506, on xenogeneic neural transplantation in rodents--comparison with cyclosporin A].

The present study was performed to compare the immunosuppressive effect of FK-506 (FK) with cyclosporin A (CyA) in xenogeneic neural transplantation in rodents. The solid grafts of embryonic ventral mesencephalic tissue from 14-day rat embryos were transplanted into the right lateral ventricle of 20 mature male mice using a stereotactic approach, and the mice were sacrificed 14 days after transplantation. The removed brains, which were sectioned coronally, were stained with antibodies against glial fibrillary acidic protein (GFAP), Lyt-2 or tyrosine hydroxylase (TH) in addition to hematoxylin-eosin and Nissl stainings. The subcutaneous (s.c.) administration of FK at a dose of 10.0 mg/kg daily for 14 days enabled the neural xenografts to survive and grow (n = 5), although all of the neural xenografts treated with CyA at a dose of 10.0 mg/kg s.c. (n = 5) or FK at a dose of 1.0 mg/kg s.c. (n = 5) daily for 14 days and ones treated without such an immunosuppressive agent (n = 5) were rejected by immunological reactions. We conclude that FK is a more powerful immunosuppressive agent than CyA in xenogeneic neural transplantation as well as in cardiac and renal allograftings.

Animals↗
PubMed1991

Effect of cimetidine on the mucosal hydroxyproline content of rat gastric lesions induced by compound 48/80.

Extensive gastric mucosal lesions developed in rats after the administration of compound 48/80 at a dose of 0.75 mg/kg daily for 3 days. The hydroxyproline content of gastric mucosa was significantly increased 4 h after the last injection of compound 48/80, and subsequently decreased as the lesions healed. Treatment with cimetidine (CAS 51481-61-9) at a dose of 50 mg/kg (twice a day for 3 days) did not affect either the development or the healing of the compound 48/80-induced gastric lesions. However, the increase in mucosal hydroxyproline content was significantly reduced by treatment with cimetidine. This fact suggests that cimetidine might have an inhibitory effect on the regeneration of collagen in gastric mucosa.

Animals↗
PubMed1991

[Examination of endoscopical ultrasonography (EUS) on carcinoid tumors of gastrointestinal tract].

In order to clarify the usefulness of EUS in the diagnosis of gastrointestinal carcinoid tumor, we examined 15 patients, who had carcinoid tumors of gastrointestinal tract (stomach: 5, duodenum: 2, rectum: 8), on the diagnosis in quality and depth by comparing endoscopical ultrasonography (EUS) with resected specimen. Carcinoid tumors of gastrointestinal tract were detected as homogenous hypoechoic tumors with sharp border in all site by EUS. Especially, it was characteristic that 14 of the 17 lesions (82%) which invaded into submucosa were mainly located in the third layer, and the second layer covered the tumor at the foot, and near the top, it touched the tumor and got indistinct. We decided the depth of invasion by comparing the hypoechoic tumor with normal structure of 5 layers. The accuracy rate was 88%. In conclusion, EUS was thought to be useful in the diagnosis and choice for treatment of carcinoid tumors of gastrointestinal tract.

Adult↗
PubMed1989

Histological evaluation of mast cells in rat gastric mucosal lesions induced by compound 48/80.

Repeated intraperitoneal administration of compound 48/80 to rats produced gastric lesions, a decrease in connective tissue mast cells (CTMCs) and an increase in gastric mucosal mast cells (MMCs). The ratio of MMC to CTMC was significantly correlated with lesion formation. A mast cell stabilizer, MAR-99 (50 mg/kg), prevented lesion formation and changes in the mast cells. Omeprazole (20 or 60 mg/kg) significantly reduced the gastric lesions, but mast cell changes persisted. Cimetidine (50 mg/kg) could not inhibit compound 48/80-induced lesions nor a decrease in CTMCs, but did prevent an increase in MMCs. These facts suggest that in compound 48/80-induced gastric lesions chemical mediators released from CTMCs might be trigger factors, while intraluminal gastric acid might be an aggravating factor. Furthermore, the increase in MMCs might be regulated by histamine released from the CTMCs via H2 receptors and have no causal relation to lesions formation.

Animals↗
PubMed1989

Fluctuation of the mucosal hydroxyproline content in compound 48/80-induced gastric lesions in rats.

Extensive gastric mucosal lesions were observed after i.p. administration of compound 48/80 (0.75 mg/kg) for 3 days to rats. The mucosal hydroxyproline content was significantly increased at 4 h after the last injection of compound 48/80 and subsequently decreased as the lesions were healed. Treatment with cimetidine (50 mg/kg, i.p.) did not prevent compound 48/80-induced gastric lesions. The increase in the mucosal hydroxyproline content was significantly reduced by treatment with cimetidine. This fact suggested that cimetidine might have an inhibitory effect on the regeneration of connective tissue.

Animals↗
PubMed1989

The role of prostaglandin D2 in the genesis of indomethacin-induced gastric lesions in rats.

Four kinds of prostaglandins (PGs), 6-keto-PGF1 alpha, PGF2 alpha, PGE2 and PGD2, in rat gastric mucosa were decreased at 1 or 6 h after oral administration of indomethacin (2 or 12 mg/kg). With 2 mg/kg of indomethacin, the PG levels had slightly recovered 6 h later. Gastric lesions were observed 6 h after administration of indomethacin (12 mg/kg), but not with 2 mg/kg. Omeprazole (20 mg/kg, i.p.) prevented ulcer formation caused by indomethacin, without improvement of the reduced gastric mucosal PG levels. PGD2 (0.5 mg/kg, p.o.) reduced indomethacin-induced gastric lesions and considerable amounts of PGD2 existed in the gastric mucosa. We conclude that H+ is a determining factor in the genesis of indomethacin-induced gastric lesions and persistent decreases in tissue PG levels also participate in ulcer formation.

Animals↗
PubMed1989

Age and sex-dependent changes in serum amylase in an apparently healthy population.

In order to determine whether changes in serum amylase are age- or sex-dependent, we evaluated age- and sex-stratified serum amylase values in subjects who were proven to be healthy by a precise preventive health examination. Results showed that serum amylase increased as age progressed, except in the 0- to 29-yr-old female group. Mean serum amylase was higher in females than in males. A previous study indicated that the etiology of the increase in amylase in elderly persons is due to a progressive decline in renal function with aging. The etiology of the sex difference, especially in the younger generation, requires further investigation. We should pay attention to the factor of age when we evaluate serum amylase.

Adolescent↗
PubMed1989

Cardiac response to upper gastrointestinal endoscopy.

In 54 subjects, cardiac function was investigated during upper gastrointestinal endoscopy with a Holter electrocardiorecorder. The heart rate of patients who were premedicated with an anticholinergic agent increased more than did that of patients who received no premedication. In the group who received no anticholinergic premedication, sinus tachycardia was evident during endoscopy, but the only clinically important change was in one patient who converted to atrial flutter from atrial fibrillation. The heart rate increased during endoscopy among patients undergoing the procedure for the first time, but it did not increase in the patients who had previously undergone endoscopy. These results show that endoscopy is a relatively safe examination from the view point of cardiac risk when performed without the administration of an anticholinergic agent, but that cardiac patients should be monitored carefully. The endoscopist should also take into consideration the psychological state of the examinees.

Adult↗
PubMed1988

The effect of a new gastric proton pump inhibitor on serotonin-induced gastric mucosal lesions in rats.

The anti-ulcer effect of NC-1300, a new proton pump inhibitor, and its effect on gastric mucosal blood flow were studied in rats. Acute gastric mucosal lesions were induced by the subcutaneous administration of serotonin, 20 mg/kg. Using the electrolytically generated hydrogen gas clearance technique, it was determined that such gastric ulceration resulted mainly from a decrease in gastric mucosal blood flow. These lesions could be inhibited to a statistically significant extent by the intravenous administration of NC-1300, 20 mg/kg, which markedly inhibited gastric acid secretion. However, the serotonin-induced decrease in gastric mucosal blood flow could not be prevented by pretreatment with 20 mg/kg of NC-1300. It was concluded that protection against serotonin-induced gastric ulceration can be achieved by markedly inhibiting gastric acid secretion.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1988

Chronic alcohol abuse leads to gastric atrophy and decreased gastric secretory capacity: a histological and physiological study.

We performed morphological and physiological studies in 43 male patients with alcohol dependence (ALC) who had no other apparent lesions in the upper gastrointestinal tract except atrophic and erosive gastritis. A gastric secretory study in which tetragastrin was used as the stimulant revealed that acid and pepsin secretion was less in ALC patients than in hospital controls (p less than 0.001). Endoscopic biopsy specimens of gastric mucosa from ALC patients revealed that atrophy of the gastric mucosa advanced with age. A strong negative correlation was also found between the secretory capacity of the stomach and the degree of atrophy. Possibly, the interval between recurrent episodes of acute mucosal damage was too short to allow complete healing of mucosal lesions. Failure to regenerate denuded epithelium would result in a decrease in the gastric secretory area. Thus, chronic alcohol abuse seems to be an etiological factor in atrophic gastritis.

Adult↗
PubMed1987

[Emphysematous pyelonephritis complicated by liver cirrhosis and diabetes mellitus: a case report and a review of the literature].

A case of emphysematous pyelonephritis is presented and a review of literatures is made. A 67-years-old woman with diabetes mellitus, complained of severe left flank pain and high fever and was referred from the department of gastroenterology. A computed tomography film demonstrated gas in the left renal parenchyma and a diagnosis of emphysematous pyelonephritis was made. She was in a state of shock and died after 4 days of conservative treatment. Emphysematous pyelonephritis is a rare, life-threatening disorder and 85 cases in the world have been reported to date. Our case is the 18th one in Japan. Its etiology, symptomatology, treatment and prognosis are discussed.

Aged↗
PubMed1986

Studies on motion sickness caused by high curve speed railway vehicles. Evaluation of the swing and its effects on passengers and conductors.

The high curve speed railway vehicles (HCSRVs) of the Japanese National Railway have been operating since 1973 with the aim of increasing speed on ordinary routes with many curve track sections. Although the aim of increased speed has been attained, it has been pointed out that the swing of HCSRVs is stronger than that of ordinary-type trains and it may increase motion sickness among the passengers and conductors. In this study, the authors examined motion sickness symptoms among 119 passengers and 100 conductors of both trains with a self-administered questionnaire, and evaluated the vibration acceleration on the floor by using the 1/3 Octave Band Analyzer and the Fast Fourier Transform method (FFT). The results can be summarized as follows: There were more passengers and conductors suffering from motion sickness riding on HCSRVs than those on the control trains. HCSRVs had the peak values of vibration acceleration within the range of 0.5 Hz and 1 Hz at horizontal, although the control train showed them above 1.0 Hz. These results suggest that the high rates of subjective complaints of passengers and conductors riding on HCSRVs were affected by vibration acceleration of frequency lower than 1 Hz.

Acceleration↗
PubMed1985

Comparative study of the work load between one-man buses and two-man buses.

The differences in physiological and safety conditions of one-man buses and two-man buses were examined from the view point of occupational fatigue. This survey consisted of a work load study which included a time study, study of subsidiary behavior, auditory task, memory test, Galvanic Skin Response (GSR) and physiological function tests and a self-administered questionnaire which involved items concerning safety and subjective fatigue complaints. The visual and postural restrictions in the one-man bus were greater than in the two-man bus. The mental capacity of the one-man bus drivers was found to be less. Greater mental fatigue and stress were observed in the one-man bus. More subjective fatigue complaints were observed in the one-man bus. More cases of near accidents were observed in the one-man bus. From these results it was concluded that the one-man bus caused bus drivers a greater mental and physical work load.

Accidents, Traffic↗
PubMed1984

Effects of consecutive night-shift work on health conditions among car-cleaners of super-express trains.

The Shinkansen Super-Express trains of the Japanese National Railways, the so-called bullet trains, run from early morning until late at night. Accordingly the car-cleaners of the Shinkansen must do late night shift work. A self-administered questionnaire survey including items about health and work conditions was given to 246 workers at Osaka Station, who were then divided into 3 groups: Group A consisted of 102 night workers working 5 successive days with 2 days off, Group B consisted of 124 alternate-day 24-hour workers working 3 days a week, while Group C included 20 day-workers working 6 days a week. A subjective fatigue inventory was administered before and after work for a week to 20 workers selected from each of three groups, group A, B above group D whose shift was 2 times 2 successive night shifts with one day off, and one holiday a week. The results of the questionnaire survey revealed that the rates of complaints such as gastroenteric disorders and general fatigue were the highest in group A. The results of the subjective fatigue inventory show a tendency for the number of complaints in group A and B to increase significantly after the last work shift of the week, but not in the case of group D. The authors demonstrated that there was a close relationship between patterns of night-shift work and various kinds of health problems, and concluded that to insert a day off on the third day of the group D shift was effective in reducing the work load.

Dizziness↗
PubMedDate not supplied

Role of nitric oxide synthase inhibitor in experimental colitis induced by 2,4,6-trinitrobenzene sulphonic acid in rats.

1. The present study was designed to investigate the role of nitric oxide (NO) in modulating 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. 2. Damage scores and NO synthase (NOS) activity were measured. 3. The damage scores and NOS activity reached a peak on the 4th day after administration of TNBS solution (day 0), thereafter gradually decreasing, and were significantly higher than in the group treated with saline throughout the experimental period. 4. Subsequently, we divided the stage of colitis into two groups, one from day 0 to day 3 after induction of colitis, and the other from day 4 onwards. We evaluated the effects of the NOS inhibitor N(G)-monomethyl-L-arginine (L-NMMA), on TNBS-hapten-induced colitis and colonic mucosal blood flow. Two different methods of L-NMMA administration, from day 0 to day 3, and from day 4 onwards, were undertaken. 5. The damage score in the early L-NMMA treatment group was significantly higher than in the group without L-NMMA on day 14. In contrast, the damage score in the late L-NMMA treatment group was not significantly different from the group without L-NMMA. Colonic mucosal blood flow in the early L-NMMA treatment group was not significantly different from that in the late L-NMMA treatment group. 6. These data suggest that NO is important for inhibiting inflammation during the early stages.

Animals↗
PubMedDate not supplied

Effects of intragastric ammonia on collagen metabolism of gastric ulcer base in rats.

We studied the chronic effect of ammonia, which is one of the pathogenic factors of Helicobacter pylori in gastroduodenal diseases, on the healing of acetic acid-induced gastric ulcers in rats with special reference to the collagen metabolism. Rats were given either tap water or 0.1 or 0.02% ammonia solution before and after ulcer induction. We measured the ulcer index, hydroxyproline concentrations and type III collagen/total hydroxyproline ratios in the ulcer base. Epithelialization was achieved 4 weeks later under the influence of ammonia. Nevertheless, ammonia treatment significantly increased the collagen deposition in the ulcer base compared with the nonammonia treatment group, 4 weeks after ulcer induction. In the nonammonia treatment group, the type III collagen/total hydroxyproline ratio decreased 3 weeks after ulcer induction. On the contrary, in the groups treated with ammonia throughout the experiment, type III collagen/total hydroxyproline ratio remained high until 4 weeks after ulcer induction. In conclusion, intragastric ammonia delayed the ulcer healing process in its early phase, but did not affect the achievement of re-epithelialization. However, it disturbed the collagen metabolism in the ulcer base. Excessive deposition of collagen and an abnormally high proportion of its immature type may be unfavorable for ulcer healing. These findings may explain in part why H. pylori-induced ulcer is so difficult to treat.

Acetic Acid↗
PubMedDate not supplied

The prevalence of gallstones in gastrectomized patients: a comparative study in a large population.

We investigated the prevalence of gallstones after gastrectomy by abdominal ultrasonography in 289 gastrectomized patients selected from 51,621 Automated Multiphasic Health Testing and Services (AMHTS) examinees after barium meal studies. The results were compared with those of another group of 3,193 AMHTS patients who routinely underwent ultrasonography (control). Among the gastrectomized patients, the overall prevalence of gallstones was 16.6%, and in the control group, 4.7%, showing a statistically significant difference (p less than 0.001). The prevalence of gallstones increased with age in both the control and gastrectomized groups, but was greater in gastrectomized subjects in each (10-yr) age group. The characteristics of the gallstones were compared between gastrectomized patients and the control group according to the ultrasonographic classification proposed by Tsuchiya (Yazawa et al, Jpn J Gastroenterol 85: 708, 1988). In the control group, the percentages of types I, II, III and small stone of Tsuchiya's classification were 30.2, 14.5, 21.9 and 34.3, respectively. On the other hand, in the gastrectomized group, the percentages were 8.3, 6.3, 16.7 and 68.8, respectively. This difference was statistically significant (p less than 0.001). The differences in the prevalence of gallstones between groups with Billroth I and II anastomoses, and between diseases necessitating gastrectomy, were not statistically significant.

Adult↗