Basic research for designing a microplate which can be applied to determination of 32P by radioluminography was carried out. It was proven that 32P can be determined by using the microplate which has plural planchets placed at intervals on a thin plate and a brass collimator that fills the gaps between the planchets. The microplate is joined with the collimator, and exposed to an imaging plate for 24 h. The detection limit of the proposed method was estimated to be 6 m Bq. The cross-talk ratio was negligibly small (0.2%).

Microchemistry↗

PubMedDate not supplied

Coordinate interaction between ATP-sensitive K+ channel and Na+, K+-ATPase modulates ischemic preconditioning.

BACKGROUND: We reported that digoxin abolishes the infarct size (IS)-limiting effect of ischemic preconditioning (IPC). Because ATP-sensitive K+ (KATP) channels are involved in IPC, we studied whether Na+,K+-ATPase and KATP channels functionally interact, thereby modulating IPC. METHODS AND RESULTS: Rabbits received 30 minutes of coronary artery occlusion followed by 3 hours of reperfusion. IPC was elicited by 5 minutes of occlusion followed by 10 minutes of reperfusion. The IS, expressed as a percentage of the area at risk, was 40.2+/-2.8% in control and 39.8+/-5.0% in digoxin pretreatment rabbits. Both IPC and pretreatment with cromakalim, a KATP channel opener, reduced IS to 11.8+/-1.8% and 13.4+/-2.6% (P<0. 05 versus control). Digoxin abolished the reduction in IS induced by IPC (33.5+/-3.3%), whereas it did not change that induced by cromakalim (18.8+/-3.0%). In patch-clamp experiments, digoxin was found to inhibit the opening of KATP channels in single ventricular myocytes in which ATP depletion had been induced by metabolic stress. In contrast, digoxin had little effect on the channel opening induced by cromakalim. Moreover, the inhibitory action of digoxin on channel activities was dependent on subsarcolemmal ATP concentration. CONCLUSIONS: The IS-limiting effect of IPC is modulated by an interaction between KATP channels and Na+,K+-ATPase through subsarcolemmal ATP.

Animals↗

PubMedDate not supplied

Health and welfare data on optical memory cards in Isehara city.

An off-line network system of health and welfare for elderly people using optical memory cards has been established in Isehara city (Japan) since 1991. 2775 citizens have the cards and 24 offices have the terminals. It covers almost one third of people aged over 65 in Isehara city and almost all of the offices concerned with their health and welfare. About a half of holders use optical memory cards every time they visit these offices. The optical memory card holds data including basic data for health and welfare, health check data over 5 years, medical images with scripts and history of welfare services. All the data are used for medical care, health consultation and management of health and welfare services. A card can hold health and welfare data for a lifetime, and it is easy to expand the system. It has been a good experience for us, because the optical memory card system needs co-operation among citizens, medical association and local government, and the experience will help us to expand the system in the future.

Aged↗

PubMedDate not supplied

Pharmacological properties of YM264, a potent and orally active antagonist of platelet-activating factor.

The anti-platelet-activating factor effect of YM264 was examined in a variety of in vitro and in vivo test systems. YM264 inhibited [3H] platelet-activating factor binding to rabbit platelet membranes with a pKi value of 8.85. YM264 inhibited the platelet-activating factor-induced human, rabbit and guinea-pig platelet aggregation with pA2 values of 8.68, 8.33 and 8.14, respectively. However, at 10(-4) M the compound did not affect rabbit and human platelet aggregation induced by ADP, collagen arachidonic acid and epinephrine. YM264 reversed a platelet-activating factor-induced hypotension is anesthetized rats with an ED50 value of 0.005 mg/kg, i.v. Administered orally, YM264 inhibited platelet-activating factor-induced death in mice, hemoconcentration in rats and increase in vascular permeability in guinea-pigs with ED50 values of 0.19, 0.30 and 0.49 mg/kg, p.o., respectively. YM264, at 1 and 3 mg/kg, p.o., showed a significant anti-platelet-activating factor effect in a rat hemoconcentration model up to 6 hr after treatment. Moreover, in ex vivo experiments in guinea-pigs, YM264, at the doses of 0.3 to 3 mg/kg, p.o., shifted the dose-response curves of platelet-activating factor-induced platelet aggregation to the right in a parallel manner. These results indicate that YM264 is a selective, potent and orally active platelet-activating factor antagonist.

Animals↗

PubMedDate not supplied

Simultaneous liquid chromatographic determination of residual synthetic antibacterials in cultured fish.

A liquid chromatographic method is described to determine simultaneously the following 11 synthetic antibacterial agents used in a fishery: nitrofuran derivatives furazolidone, nifurpirinol, difurazone, and furamizole; sulfa drugs sulfamerazine, sulfisozole, sulfamonomethoxine, and sulfadimethoxine; and, oxolinic, nalidixic, and piromidic acids. A Nucleosil C18 column was used with tetrahydrofuran-acetonitrile-phosphoric acid-water (29 + 1 + 0.06 + 69.94) as the mobile phase. Pretreatment of the fish meat sample with acetone extraction and alumina column cleanup gave good separation of the LC peaks without interference from any other components. Recovery of the antibacterial agents was ca 80%. The lower limit of detection of the drugs was 1-2 ng for 10 microL injection.

Animals↗

PubMedDate not supplied

Further structural analysis of urinary metabolites of suprofen in the rat.

The urinary metabolites of 2-(4-(2-thienylcarbonyl)phenyl)propionic acid (suprofen, S) in rats were analyzed by radio-GC, GC/MS, or 1H NMR technique. Radio-GC analysis of trimethylsilylated materials after TLC separation of intact urine showed the presence of three radioactive peaks with the retention times corresponding to the authentic S, 2-(4-(2-thienylhydroxymethyl)phenyl)propionic acid, and 2-(4-carboxyphenyl)propionic acid. About 40% of the total radioactivity appearing in the 0-24-hr urine was accounted for by the three metabolites and their conjugates. The identification of these metabolites was confirmed by comparison of the MS spectra of urine, in which rats were administered an equimolar mixture of S and S[phenyl-d4], with those of synthetic standards. The labile metabolites of S, corresponding to about 32% of the total radioactivity appearing in the 0-24-hr urine, were isolated and purified by ether extraction from the fresh urine and GC/MS or HPLC. GC/MS of the methylated metabolite revealed the consistent presence of the ion peaks at m/z 304, 245, 217, and 141, indicative of a dimethylated product with monohydroxy group on the thiophene ring. Analysis of the 1H NMR spectrum demonstrated the metabolite to be 2-(4-(5-hydroxy-2-thienylcarbonyl)phenyl)propionic acid.

Animals↗

PubMedDate not supplied

Metabolism of suprofen in the dog.

Explore the source record for details and available documents.

Animals↗