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Biomedical subjects

T Urano

Publications and source records attributed to T Urano.

At least 307 records · Page 17Linked to original sources
PubMed1982

Biochemical aspects of experimental barbital dependence III: effect on neural energy reserve system.

The effect of barbital intoxication on the neural energy reserve of rat was examined. The energy metabolism was depressed at dependent developing stage and recover to the non treated level at dependent stage. After withdrawal, rapid degradation of creatine phosphate and adenosine triphosphate was recognized. Later stage of withdrawal, the sum of creatine phosphate and adenosine triphosphate was decreased, and adenosine diphosphate and adenosine monophosphate was remarkably increased. These changes in neural energy reserve were parallel to the changes in adenylate cyclase activity and carbohydrate metabolism which were previously presented. These changes may have possible role in development of drug dependence and or withdrawal.

Adenosine Triphosphate↗
PubMed1982

[Effects of combined administration of morphine and ethanol on drug selecting behaviors and the development of drug dependence].

The purpose of the present paper is to investigate the effect of combined treatment of morphine and ethanol on preference for morphine or ethanol and morphine dependence formation. Rats were treated with morphine by DAF (drug-admixed food; 0.5 and 1 mg/g food) method or subcutaneous injection (20-100 mg/kg body weight), and/or treated with ethanol solution (5 and 10 w/w %) or oral administration (2.5 g/kg body weight). There were no effects of chronic treatment of ethanol and morphine on preference for morphine and ethanol, respectively. While, preference for morphine did not increase and preference for ethanol enhanced markedly in rats chronically treated with morphine and ethanol. Effect of chronic ethanol treatment on morphine physical dependence formation in rats was evaluated by body weight loss after morphine withdrawal, and the weight loss significantly attenuated and diarrhea was suppressed in comparison with morphine alone group. These results indicated that preference for morphine and morphine physical dependence formation were reduced when rats were chronically treated with ethanol during chronic morphine treatment, and that preference for ethanol was enhanced.

Animals↗
PubMed1981

Tolerance to and dependence on barbiturates in mice reference to the data in rats.

The experimental results on tolerance to and dependence on phenobarbital (PhB) in male, ICR mice were compared with results previously reported in the case of rats. When food admixed with 1 and 2 mg PhB/g food was administered daily for 13 consecutive days, the mice began to acquire tolerance to PhB from the 4th day or so (rotarod performance test), with little suppression being observed on days 6 or 7. These results indicate that tolerance to PhB is acquired earlier in mice than in rats. The blood and brain concentrations of PhB during the dosing period were reduced abruptly on the 3rd or 4th day, corresponding well with the time course changes in the development of tolerance shown by rotarod performance. The mice were given daily doses of PhB increasing stepwise from 0.5 and 1 mg PhB/g food to 4 mg PhB/g food, over 39 consecutive days. With this gradually increasing dose regimen, the animals maintained moderate to severe depression of CNS throughout the dosing period. The blood and brain half-life of PhB after withdrawal were 16 and 8 hr respectively. From 17 to 24 hours after withdrawal of PhB, the animals showed signs of systemic tremors, Straub-tail, hyperkinesia, wild running "rum fits" and clonic-tonic convulsions. Contrary to the findings in rats, in which there was a frequent incidence of convulsion from 17 to 48 hours after withdrawal, the duration of the characteristic signs after barbiturate withdrawal was obviously short-term. These results suggest that may be more reasonable to use rats in preference to mice as a preclinical model of dependence, especially in cross-physical dependence tests for sedative-hypnotic drugs.

Animals↗
PubMed1981

Enhancement of drug withdrawal convulsion by combinations of phenobarbital and antipsychotic agents.

Antipsychotic agents which are considered to depressive to the central nervous system (CNS) but free of dependence liability were used in combination with barbiturates or tranquilizers to study the physical dependence liability in the so-enhanced CNS depression. In the study of physical dependence formation, when CNS depression was maintained in an enhanced stage during the continuous application of the drug combinations, the withdrawal convulsions were enhanced in both frequency and severity. In the crossphysical dependence study, two-drug combinations, i.e., phenobarbital (PhB)-chloropromazine (CPZ), PhB-diphenhydramine (DPH) and nitrazepam-chlorprothixene, and 3-drug combinations (i.e., PhB-CPZ-promethazine and PhB-CPZ-DPH were evaluated. The 2-drug combinations suppressed some of the withdrawal signs, but those at high dosages showed a tendency to aggravate the signs. The 3-drug combinations differed from the 2-drug combinations in that the suppression of withdrawal signs was synergistically enhanced and the barbital withdrawal signs were weak. In conclusion, when CNS depression with PhB was enhanced with combinations of dependence liability-free drugs the drug combinations enhanced withdrawal convulsions both in frequency and severity. The sedation enhanced by the combinations did not always parallel the suppression of barbital withdrawal.

Animals↗
PubMed1981

Prevalence of feline viral antibodies in random-source laboratory cats.

Over a period of 1973 to 1979, a serologic survey of virus infections was conducted on feline sera collected in four universities which located in different prefectures; Obihiro, Saitama, Kanagawa and Tokyo. A significant hemagglutination-inhibition (HI) antibody titer of 1 : 8 or higher to feline panleukopenia virus (FPLV) was detected in 130 (58%) of the 226 sera used. No remarkable difference in the HI antibody prevalence in cats to FPLV was recognized by years or localities. Of a total of 188 cats tested, 99 (53%) presented positive serum neutralizing (SN) antibody titers to the No. 1 strain of feline calicivirus (FCV). Especially in Kanagawa, 17 (77%) of the 22 cats had positive SN titers. However, only 42 (22%) of the 188 sera showed positive SN titers to the Kyoritsu strain of FCV. Such lower positivity in the cats was observed with 13% in the SN test to human reovirus type 3 (Reo-3). The incidence of positive SN antibodies to feline rhinotracheitis virus (FRV) also remained in low values of 20 to 27% with the exception of high percentage of 86 in Tokyo. The dissemination of FPLV, FRV, FCV and Reo-3 was briefly discussed in relation with the age distribution of viral antibodies in cats.

Animals↗
PubMed1981

Role of gastrointestinal microflora in nitrogen and mineral balances in young mice fed on autoclaved and irradiated diets.

Male germ-free (GF) and conventional (CV) mice were fed on steam-sterilized (autoclaved for 30 min at 121 degrees C) and gamma irradiation-sterilized (5 Mrad with 60Co) diets for a one-week adjustment period from 4 weeks of age. During the subsequent week, the amounts of feed eaten were determined, and the feces and urine were collected eaily. The effects of the mode of diet sterilization and intestinal microflora on the feed consumption, body weight gain, feed efficiency (body weight gain/feed consumption), feed N efficiency (body weight gain/feed N consumption), and the excretion, absorption and retention of N, Ca, Mg and P and the bone deposits of these minerals were investigated. 1) The method of sterilization of the diet did not appreciably influence these parameters, except for the apparent digestibility of N and ratio of N retention. Compared to autoclaved diet-fed mice, irradiated diet-fed mice showed a higher apparent digestibility of of N and lower ratio of N retention. 2) Feed consumption in both GF and CV mice showed no major differences. Body weight gain, feed efficiency and feed N efficiency were higher in GF mice than in CV mice. 3) GF conditions increased the apparent digestibility of N, Ca, Mg and P. Lower total excretion of N, Ca and P in the feces and urine, a higher retention of Ca and P, and higher ratios of retention of N and these minerals were observed in GF mice. 4) The results in GF mice indicated a higher weight of moisture- and fat-free bone and a higher Ca, Mg and P concentration in the bones (femurs and tibias with fibulas) with respect to the body weight minus the weight of the digesta.

Animals↗
PubMed1981

Enterobacter cloacae, Serratia marcescens and Yersinia enterocolitica in colonies of laboratory mice, rats and rabbits: an attempt of isolation.

An attempt to isolate Enterobacter cloacae, Serratia marcescens and Yersinia enterocolitica was made in a total of 931 laboratory animals (mice, rats and rabbits) from five representative commercial breeders in this country and from our laboratory colonies. E. cloacae organisms were isolated from feces and other specimens of 15 mice and 17 rats between November 1979 and July 1980. Neither S. marcescens nor Y. enterocolitica was detectable in any specimen of feces, fur and skin, nasal discharge, lungs, urinary bladder or urine from the animals examined.

Animals↗
PubMed1980

Drug resistance of organisms isolated from feces of laboratory mice and rats.

A total of 248 strains of EScherichia coli, 132 of Staphylococcus epidermidis, 137 of Streptococcus faecalis and 89 of STr. faecium were collected from feces of 40 mice and 36 rats of 8 colonies in 1978, and drug resistance were examined by an agar dieution method using 23 antibiotics. The results indicated a positive relation between use of antibiotics and appearance of multiple drug resistant organisms.

Animals↗
PubMed1980

[Methylmercury toxicosis. I. Relationship between the onset of motor incoordination and mercury contents in the brain (author's transl)].

Mice were given one or repeated administrations of methylmercury chloride (MMC) in an attempt to determine the sexual differences as related to toxic signs, particularly, motor incoordination and the period to evolvement of toxicity. Male and female mice were given 50.6 mg/kg of MMC (about equal to the LD50 in female mice) orally only once, and changes in general behavior and mortality were observed for the following 13 days. Another group of male and female mice was fed food containing 50 and 100 ppm of MMC for 30 days, respectively. The rotarod performance test was carried out daily during the application period, to compare the onset stages of toxic signs and motor incoordination between the groups. The mercury content of the brain was measured at 1- to 2-day intervals during the application period. When the animals were given MMC only once, the males began to die at 3 days, 7/8 of the group dying by the 7th day, while the females began to die at 8 days, with 5/8 of the group dying thereafter: there was thus an obvious sexual difference in the toxicity. When the animals were given MMC admixed with food, however, the females proved more sensitive to the compound both in onset and severity of toxic signs. The onset was seen in the females at the stage when they had ingested about half the amount of the toxic food ingested by the males. The onset and the period in days to the onset of suppressed rotarod performance both in the groups on 50 and 100 ppm were correlated to the daily intake of MMC, the total MMC intake to the onset in the 2 groups being similar. The accumulation of mercury in the brain increased linearly in both groups, with the MMC content of the brain at the onset was about 20 microgram Hg per g of brain (on the wet basis), i.e., about twice that of the human brain. The mercury content in the brain of the female mice tended to reach the toxicity threshold earlier than that in the brain of the males.

Animals↗
PubMed1979

Influence of coagulation on the activation of plasminogen by streptokinase and urokinase.

Human plasma was mixed with Ca++ or thrombin, and urokinase (UK) or streptokinase (SK) and a chromogenic substrate (S-2251: H-D-Val-Leu-Lys-pNA) specific to plasmin. The hydrolysis of S-2251 was higher when clot was formed by the addition of Ca++ or thrombin than in the absence of clot. The hydrolysis of S-2251 by euglobulin in the presence of UK was also higher when clot was formed, thus, inhibitors may not be related to the better activation of plasminogen, in the presence of fibrin clot. It may be suggested that plasminogen was better activated by activators (UK and SK) in the clot than in its absence.

Blood Coagulation↗
PubMed1978

Provocation of pseudomoniasis with cyclophosphamide in mice.

After treatment with cyclophosphamide, a fatal syndrome was found in mice contaminated with Pseudomonas aeruginosa. The syndrome seems to be caused by P. aeruginosa from the intestine, and the liver is suspected to be the most important target organ.

Animals↗
PubMed1978

[Distribution of Pseudomonas aeruginosa in experimentally infected mice (author's transl)].

The distribution of experimentally administered Pseudomonas aeruginosa was studied in germfree CF no. 1 mice, barrier-sustained DDD mice with or without oral treatment of aminobenzyl-penicillin and conventional DDD mice. On day 1 after oral administration of 8 X 10(7) organisms, more than 10(8) of organisms/g were recovered from the feces of ex-germfree mice and the number was maintained during the experiment. On the other hand, from barrier-sustained mice with antibiotic treatment and those without the treatment, 10(4-7) and 10(3) organisms were recovered, respectively. In all of monoassociated mice and some antibiotic-treated barrier-sustained ones the organisms were recovered also from the lungs, liver, spleen and kidneys. In conventional mice, however, no organisms were recovered from the internal organs throughout the experiment, while some were detectable from the intestinal tracts. The distribution of the organisms in naturally infected mice appears to be similar to that of experimentally infected animals with antibiotics.

Ampicillin↗