Biomedical subjects

C van Creveld

Publications and source records attributed to C van Creveld.

4 recordsLinked to original sources

PubMed1996

The bioavailability of febantel in dehydrated camels.

In the present study the bioavailability of febantel paste and febantel suspension was investigated in the fully hydrated and the dehydrated camel. The serum concentrations of febantel and its metabolites, fenbendazole, oxfendazole and fenbendazole sulfone were determined by high performance liquid chromatography following extraction with ether. The exposure to febantel and its metabolites in fully hydrated camels was significantly higher in camels dosed with febantel paste compared to febantel suspension, as measured by AUC and Cmax. The AUC and Cmax of fenbendazole and oxfendazole were significantly lower in dehydrated camels as compared to control camels dosed with febantel paste. The systemic availability of febantel suspension in control and dehydrated camels was very low and differences between dehydration and control phases were insignificant. The low systemic availability of febantel in camels dosed with febantel suspension may cause nematodes to become resistant to this anthelmintic. It is, thus, suggested to increase the dose of febantel paste in dehydrated camels in order to increase the exposure to febantel and its metabolites. The binding of febantel, fenbendazole, oxfendazole and fenbendazole sulfone to camels' serum proteins was over 85%. Oxfendazole was only about 70% bound. Dehydration of 10 days did not affect the binding of these benzimidazole derivatives to serum proteins.

Administration, Oral↗

PubMed1989

Liver function and protein binding in camels.

1. Dehydration of camels for 10 days resulted in reduction of liver functions, expressed in longer half life and reduced clearance of bromosulfophthalein (BSP), elevated AST (ALT levels were below the limit of detection of the method) and reduced serum albumin concentrations. 2. Binding of BSP to camel serum proteins by gel permeation chromatography and by equilibrium dialysis showed very strong binding. 3. Binding parameters of various drugs to camels serum by equilibrium dialysis showed close similarities both qualitatively and quantitatively to those of humans. 4. Albumin seems to be the major serum binding protein of BSP.

Alanine Transaminase↗

PubMed1989

Reference blood chemical values in ostriches (Struthio camelus).

Reference blood chemical values were determined for 65 male and 61 female ostriches (Struthio camelus) 1 month to 72 months of age. Plasma values of glucose, total protein, triglycerides, cholesterol, uric acid, urea, bilirubin, creatinine, osmolality, electrolytes, and enzyme activity were determined. In general, differences in various values appeared mainly among age groups and less so between sexes. Older ostriches had lower plasma glucose values and enzyme activity than did younger ostriches. High plasma sodium and chloride concentrations in young ostriches correlated with high plasma osmolalities. Plasma calcium values were lower in laying ostriches. Uric acid concentrations were markedly higher than were urea concentrations in all ostriches.

Age Factors↗

PubMed1986

Theophylline pharmacokinetics in pregnant and lactating rats.

As a preliminary investigation to a human study, we examined the pharmacokinetics of theophylline in pregnant and lactating rats. Three groups of female rats--pregnant, lactating, and virgin controls were injected IP with theophylline solution. Pregnant rats eliminated theophylline at a slower rate than both lactating rats and virgin controls, resulting in a longer half life (t1/2) and lower clearance. The approximate volume of distribution (aVd) and extrapolated peak concentration (Cp0) in the 3 groups were not different.

Animals↗