Effect of ranitidine on acetaminophen-induced hepatotoxicity in dogs

The effect of ranitidine administration upon the hepatotoxic effect produced by a multidose acetaminophen administration regimen was examined. Seventy-two dogs received three subcutaneous injections of acetaminophen (750, 200, 200 mg/kg body wt) in DMSO (600 mg/ml) at time zero, 9 hr later, and 24 hr after the first dose. Ten control animals (group I) were not given ranitidine, the remaining 62 dogs received an intramus-cular injection of ranitidine 30 min before each acetaminophen dose. Three different doses of ranitidine were used (mg/kg body wt): 50 mg, group II (33 dogs); 75 mg, group III (14 dogs); 120 mg, group IV (15 dogs). Ranitidine reduced the expected acetaminophen-induced hepatoxicity in a dose-response manner. Moreover, a significant correlation was found between the ranitidine dose and the survival rate, as evidenced by transaminase levels in the serum and histology of the liver. This model of fulminant hepatic failure induced by acetaminophen and its modulation with ranitidine provides clinical investigators with a research tool that will be useful in the future investigation of putative medical and surgical therapies being investigated for use in the clinical management of fulminant hepatic failure. Because of the size of the animal used in this model, frequent and serial analyses of blood and liver were available for study to determine the effect of therapy within a given animal as opposed to within groups of animals. © 1990 Plenum Publishing Corporation

Nanometer Sized Silver Particles Embedded Silica Particles—Spray Method

Spherical shaped, nanometer to micro meter sized silica particles were prepared in a homogeneous nature by spray technique. Silver nanoparticles were produced over the surface of the silica grains in a harmonized manner. The size of silver and silica particles was effectively controlled by the precursors and catalysts. The electrostatic repulsion among the silica spheres and the electro static attraction between silica spheres and silver particles make the synchronized structure of the synthesized particles and the morphological images are revealed by transmission electron microscope. The silver ions are reduced by sodium borohydride. Infra red spectroscopy and X-ray photoelectron spectroscopy analysis confirm the formation of silver–silica composite particles. Thermal stability of the prepared particles obtained from thermal analysis ensures its higher temperature applications. The resultant silver embedded silica particles can be easily suspended in diverse solvents and would be useful for variety of applications

Preparation and characterization of HfO2_{2} thin films by photo-assisted MOCVD

High-k dielectric HfO$_{2}$ thin films have been prepared by photo-assisted metal-organic chemical vapor deposition (MOCVD). Vacuum ultraviolet (VUV) light is used for enhancement of chemical reaction of the source materials of (Hf(O-t-C$_{4}$H$_{9})_{4})$ (HTB) and H$_{2}$O. The absorption spectrum of HTB has been calculated with molecular orbital method. The calculated infrared absorption of HTB is found in VUV region (around 150 nm), and HfO$_{2}$ thin films were deposited under the irradiation with VUV light of a D$_{2}$ lamp including the HTB absorption band. These prepared films are characterized by FT-IR measurement to estimate the concentration of organic impurities. It shows that C-H peak drastically decreases less in the photo-assisted MOCVD film than the MOCVD. Moreover, C-V characteristics show that accumulation capacitance is increased in the film deposited under VUV irradiation. The accumulation capacitance is much increased by rapid thermal annealing (RTA) in the case of photo-assisted MOCVD. AFM observation results show that very smooth surface is obtained in the photo-assisted MOCVD films