Lead levels in tissues of animals slaughtered in Ismailia slaughterhouse

Liver, kidney and muscle samples from a total number of 246 animals of cattle [73], buffaloes [74], camels [37], sheep and goats [62] aging from one to 7 years old were collected and analysed using atomic absorption spectrophotometer for estimation of lead residues. According to the Egyptian Standards [ES] [2360/2007], lead concentrations in buffalo and cow muscles were generally low and far away from the maximum residual limit. On the other hand, 18.75% of both kidneys and livers, 68.75% of muscles of slaughtered ole camels and 52.4% of young camel muscles contained residual lead more than the permissible limit. Meanwhile, most of the examined samples of old sheep and goats and half of sheep and goats under three years contained residual lead more than the permissible limit in their tissues. There was a significant [P<0.05] increase in lead concentration in relation to the age in case of all of the examined animals except for female buffaloes. Also there was a significant [P<0.05] linear relationship between the concentrations of lead in livers and kidneys for the same animal

study of compressive strength and fluoride release from light-cured and auto-cured glass ionomer cement liners

This study attempted to evaluate one type of light-cured glass ionomer cement liner [Vitra-bond] compared with conventional auto-cured type [Ketac-bond] through the study of compressive strength at different periods of time [1 hour, 24 hours, and 1 week following mixing] and the measurement of fluoride released from them in artificial saliva every 24 hours for 30 days were investigated. From the present study, it is concluded that the compressive strength values for both light and auto-cured glass ionomer liners tested increased with time. There was no significant differences between them in the 1 hour compressive strength values, while highly significant differences were noted after 24 hours and 1 week. In general, the strength of Vitra-bond was greater than that of Ketac-bond at the different periods of measurements. Fluoride release patterns were similar for all glass-ionomer cements tested, i.e. a large initial release was followed by a rapid decline in the amount released with some fluctuation within the observation period [30 days]. Vitra-bond showed the highest mean values of fluoride release, while Ketac-bond showed the lowest values over the test period

Study of the release mechanism of a water soluble drug from hydroxypropyl methylcellulose matrices

Directly compressed tablets of pyridoxine HCl in hydroxypropylmethylcellulose [HPMC] matrices containing different polymer ratios, and in HPMC matrices containing various proportions of additives; namely, sodium alginate, pectin, veegum or kaolin or various proportions of an effervescent mixture, were prepared. A double layer floating tablet was also designed. The release characteristics of the tablets were studied in either 0.1 NCl or phosphate buffer [pH 7.4]. The data were fitted into an equation relating release rate constants responsible for diffusional and relaxational processes to determine the relative contribution of the two phenomena on the overall drug release mechanism. The release of the vitamin from the simple HPMC matrix and the one containing an effervescent mixture was slower in 0.1N HCl than in phosphate buffer. The reverse was true in the presence of the additives. The floating tablets in acid medium showed a decrease in the release rate. The formulation containing drug, HPMC, sodium alginate [1:2:0.5] can be proposed for further practical application

Effect of some pharmaceutical additives on the theological characteristics of plum gum dispersions

In this study, the addition of glucose and sucrose in a concentration range of 0.1-0.5 mole/L to the gum dispersions increased their relative viscosity. The effect of sucrose was more pronounced than that of glucose. The relative viscosity of the gum dispersion was decreased. The chlorides of sodium, calcium and aluminum decreased the relative viscosity of the plum gum dispersions. The decrease in the relative viscosity seems to depend on the cation valency. The reduction in the presence of trivalent cation [Al 3+] was more than that in the presence of monovalent cation [Na +]. The effect of surfactants on the relative viscosity was also investigated

Theological studies on plum gum dispersions: I general flow characteristics

The rheology of plum gum dispersion was studied utilizing the reoviscometer. The rheogram of 5% w/w gum dispersion is indicative of a pseudoplastic system, which becomes clearly plastic upon increasing gum concentration. It was also evident that sum dispersions exhibit thixotropic behavior. At relatively low concentrations [0.25-2% w/w], it was not possible to establish the actual flow pattern. Therefore, the characterization was based on measurements of relative viscosities. Various factors which influence the relative viscosity of gum dispersion, as gum concentration, preservatives type, hydrogen ion concentration and effect of heat were studied in the light of the factor of time. The relative viscosity of 2% w/w gum dispersion was reduced by about 90% by increasing the temperature from 25C to 100C. On aging, the dispersions lost part of their viscosities. Phenylmercuric nitrate was found to be the best among the other preservatives tested. Plum dispersions appeared to be most stable at pH 6 and lowering in the relative viscosities was noticed on aging

Dissolution of cholesterol in bile salt solutions: effect of a nonionic surfactant [triton X-114]

A nonionic surfactant, Triton X-114, was shown to increase the dissolution rate of cholesterol in bile salt solutions, the effect being concentration dependent. The dissolution data obtained with Triton X-114 using a series of dihydroxy and trihydroxy bile salts and those obtained with cetrimIde indicate that the accelerating effect of the nonionic surfactant may involve the formation of bile salt-nonionic surfactant systems of higher solubilizing capacity for cholesterol which enhances the dissolution process. The results obtained provide information on this class of compOunds as potential cholesterol dissolution enhancers