Biomedical subjects

M J Rathbone

Publications and source records attributed to M J Rathbone.

5 recordsLinked to original sources

PubMed2001

Recent advances in bovine reproductive endocrinology and physiology and their impact on drug delivery system design for the control of the estrous cycle in cattle.

When methods of drug intervention are being developed to control estrous cycles, a thorough understanding of the endocrine and functional changes together with the reproductive behavior of the animals are essential. This review presents our current knowledge on reproductive endocrinology, physiology and behavior, and the methods of drug intervention to control estrous cycles. It also describes current efforts to develop advanced drug delivery systems that meet the animal scientist's demands to control the estrous cycle in cattle.

Animals↗

PubMed1999

Local delivery of chlorhexidine using a tooth-bonded delivery system.

Films containing 20% w/w chlorhexidine base (particle size 63-125 microm) in poly(epsilon-caprolactone), MW 35,000-45,000, were prepared by solvent evaporation and sections attached to the mesio-lingual and mesio-buccal surfaces of the lower first molar in healthy volunteers. Saliva (<1.5 microl) was collected on Periopaper and chlorhexidine concentrations measured by HPLC were typically higher in the area immediately adjacent to the tooth-bonded film sections and lower at more distant sites. Analysis of variance of chlorhexidine concentrations, adjacent to the film sections, showed concentrations were significantly different on the buccal and lingual sides of the tooth and depended on the time of sampling (n=5, P<0.05).

Administration, Oral↗

PubMed1998

Fertility regulation in cattle.

This paper reviews the physiological, endocrinological and pharmaceutical literature pertaining to the design, development and optimisation of subcutaneous and intravaginal progestogen-containing drug delivery systems used in the control of synchrony and ovulation in cattle.

Administration, Cutaneous↗

PubMed1998

Controlled-release products for the control of the estrus cycle in cattle, sheep, goats, deer, pigs, and horses.

This paper describes the estrus cycles of a number of livestock breeds and reviews the controlled-release drug delivery systems that are currently available for the purpose of controlled breeding. The bovine estrus cycle is reviewed in detail, and the estrus cycles of other species are described in a manner that highlights similarities and differences between species. Pertinent formulation and pharmacokinetic information about current drug delivery systems is presented and discussed, and recent advances in this area are also described.

Animals↗

PubMed1995

Determination of small sample volumes in the analysis of drugs at specific sites in the oral cavity.

Two methods for the determination of sample volumes between 0.2 and 0.6 microliters were compared by preparing standard curves for volumes over this range. The first method used a Periotron and the second the sample mass. A linear model was fitted and 95% confidence limits for volumes estimated by each method were calculated. This showed that use of either the maximum Periotron reading or the sample mass allowed estimation of volumes to within +/- 0.056 microliter and +/- 0.047 microliter respectively. It is proposed that measurement of sample mass provides a simple and accurate method to determine sample volume when analysing drug concentrations at specific sites in the oral cavity.

Delayed-Action Preparations↗