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T Arita

Publications and source records attributed to T Arita.

At least 127 records · Page 7Linked to original sources
PubMed1981

Effect of furosemide in congestive heart failure.

The diuretic effect of furosemide was studied in 18 patients with congestive heart failure. Subjects were divided into two groups, group I consisting of eight patients with moderate and group II of 10 patients with advanced congestive heart failure. Six hours after bolus injection of furosemide (40 mg), mean urinary sodium was 120.5 +/- 36.7 mEq in group I and 68.2 +/- 25.8 mEq in group II (p less than 0.01), mean urine volume was 1,100 +/- 281 and 764 +/- 257 ml (p less than 0.05), mean urinary furosemide excretion was 28.08 +/- 2.60 and 24.00 +/- 0.74 mg (p less than 0.05), and mean furosemide renal clearance was 73.4 +/- 16.6 and 42.3 +/- 11.5 ml/min (p less than 0.001). Diuretic effect and furosemide renal clearance, as well as urinary furosemide excretion, correlated positively. The diuretic effect of furosemide with and without hydralazine (0.2 mg/kg) was compared in eight patients in group II. Urinary sodium excretion 6 hr after furosemide rose from 77.2 +/- 31.0 to 122.8 +/- 42.5 mEq after furosemide with hydralazine (p less than 0.01). Urine volume rose from 854 +/- 278 to 1,279 +/- 359 ml (p less than 0.001), urinary furosemide excretion rose from 23.64 +/- 2.03 to 26.94 +/- 2.30 mg (p less than 0.01), and furosemide renal clearance rose from 46.3 +/- 12.2 to 62.5 +/- 18.6 ml/min (p less than 0.01).

Adult↗
PubMed1981

The behavior of pentaerythritol tetranicotinate in rat gastrointestinal tract as a prodrug.

The gas chromatographic assay method for pentaerythritol tetranicotinate, a nicotinic acid prodrug, and its hydrolysates was developed. The behavior of the drug in gastrointestinal tract was investigated in rat by using the method. The disappearance and hydrolysis of the drug were not observed in the gastric loop until 30 min. The rate of disappearance from the intestinal loop was 36.7% at 30 min which was significantly smaller than that of nicotinic acid. Little hydrolysis of the drug was observed in the buffer solution, pH 7.4, at 37 degrees up to 2 hr. However, the consecutive hydrolysis was observed when the drug was incubated with everted intestine or plasma. As to the rate of hydrolysis of the drug and its esterform hydrolysates by scraped intestinal mucosa, the ester to which the larger number of nicotinic acid was bound was hydrolyzed more rapidly. These results indicate that the orally administered drug is enzymatically hydrolyzed in the intestinal mucosa by a consecutive reaction. Although the hydrolysis rate of pentaerythritol tetranicotinate is rapid, the rate of its ester-form hydrolysate becomes slower gradually as the nicotinic acid is released. The released nicotinic acid is rapidly absorbed. The behavior of the drug revealed in this study suggests that pentaerythritol tetranicotinate is useful as a prodrug of nicotinic acid.

Animals↗
PubMed1981

Changes in mitochondrial function by lipid peroxidation and their inhibition by biscoclaurin alkaloid.

During in vitro investigation of changes in mitochondrial function accompanying lipid peroxidation, it was found that cepharanthine, a biscoclaurin alkaloid, protects against such change. Results obtained were as follows: (1) Fe2+ induces lipid peroxidation of isolated mitochondria, resulting in diminished oxidative phosphorylation. (2) This diminishment largely depends on deterioration of ion compartmentation of the membrane and an increase in latent ATPase activity. (3) The Fe2+-induced deterioration in ion compartmentation is inhibited by cepharanthine. (4) Cepharanthine inhibits the mitochondrial lipid peroxidation induced by Fe2+. (5) Cepharanthine inhibits the lipid peroxidation of soybean lecithin liposomes by 60Co-irradiation.

Adenosine Triphosphatases↗
PubMed1979

Release characteristics of dibucaine dispersed in konjac gels.

A possible use of konjac gel for sustained release of drugs was examined in a monolithic system containing dibucaine. Dibucaine was dispersed in the gel which was prepared by gelation of the konjac flour in a borax solution at 60 degrees. The cumulative amount of the drug released plotted against the square root of time was linear in the monolithic system. This relationship was in agreement with that expected from the theoretical equation for planar configuration. The mechanism of the release of the drug from the gel may be considered to be leaching of the drug by the permeating fluid. The release profile from dried konjac gel was similar to that from undried gel, but that from unwarmed gel showed a deviation from linearity although sustained release was similarly obtained.

Delayed-Action Preparations↗
PubMed1979

[Degradation of ampicillin by urine of patients with complicated urinary tract infections and its protective effect of dicloxacillin (author's transl)].

In vitro enzymatic degradation rate of ampicillin (AB-PC) in urine of patients with complicated urinary tract infection and its protective effect of dicloxacillin (MDI-PC) was studied using a specific fluorometric assay for aminobenzylpenicilloic acid (AB-PA), which is converted from AB-PC by bacterial beta-lactamase. The results showed that average degradation rate of AB-PC in the urine of 10 patients were 12.2%, 21.5%, 34.3% and 48.2% at 15, 30, 60 and 120 minutes, respectively. While MDI-PC prevented the enzymatic transformation of AB-PC in such urinary samples and the average degradation rates at 15, 30, 60 and 120 minutes were considerably reduced to 7.7%, 12.2%, 21.6% and 32.8%, respectively. In vivo urinary excretion rate of AB-PA was compared between a total of 5 patients and 4 healthy volunteers after oral administration of 250 mg AB-PC. It was found that the patients excreted 9.1%, 10.7% and 12.7% of total dose at 0 approximately to 2 hours, 2 approximately to 4 hours, 4 approximately to 6 hours, respectively, while the average excretion rates in healthy volunteers were 1.54%, 2.88% and 7.94%, respectively. In 4 patients cross-over administration study, the combined dose of AB-PC and MDI-PC has been proved to clearly decrease the urinary excretion rate of AB-PA in 2 cases, but there was no significant difference in the average rate between the single and the combined dose.

Ampicillin↗