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Biomedical subjects

M D Rose

Publications and source records attributed to M D Rose.

84 records · Page 5Linked to original sources

Bipedal behavior of olive baboons (Papio anubis) and its relevance to an understanding of the evolution of human bipedalism.

The bipedal behavior of a troop of olive baboons (Papio anubis) is described. Bipedalism is relatively rare but nevertheless occurs in a wide variety of situations, although bipedalism during feeding occurs much more frequently than in other situations. The incidence of bipedalism varies between different age-sex classes and between individuals within age-sex classes. This pattern of bipedalism occurred within an overall adaptive response, particularly in feeding behavior, which was similar to that of the gelada baboon (Theropithecus gelada). The data on bipedalism is used together with an existing model of early hominid differentiation based on T. gelada to indicate the types of bipedal behavior which might have occurred in early hominid small object feeders and to suggest how a bipedal pattern of this type might have served as a basis for the action of selection for a more committedly bipedal pattern at later stages of hominid evolution.

Age Factors↗

Migration from plasticized films into foods. 1. Migration of di-(2-ethylhexyl)adipate from PVC films during home-use and microwave cooking.

Migration of di-(2-ethylhexyl)adipate (DEHA) into a diverse range of foods arising from the domestic use of plasticized PVC films has been determined using a stable isotope dilution GC/MS procedure. Aspects of home use reported in this study include the wrapping and covering of foods such as cheese, cooked meats, sandwiches, cakes, fresh fruit and vegetables; the use of films during food preparation such as marinading; covering during microwave reheating of previously prepared foods, and covering during microwave cooking. Contact between film and foods was for differing temperatures and times, representative of the range of conditions likely to be experienced in practice in the home. Migration increased with both the length of contact time and temperature of exposure, with the highest levels observed where there was a direct contact between the film and food, and where the latter had a high fat content on the contact surface. Highest levels of migration were observed for cheese, cooked meats, cakes and for microwave-cooked foods, whilst lower levels were observed for wrapping of unfilled sandwiches, fruit and vegetables (except avocado), and for food preparation including microwave reheating where there was covering of the food in a container but little or no direct contact.

Adipates↗

The effect of cooking on veterinary drug residues in food: 1. Clenbuterol.

The heat stability of clenbuterol was investigated. The drug was shown to be stable in boiling water at 100 degrees C. In cooking oil at 260 degrees C, losses were observed, indicating a half-life of about 5 min. The effect of a range of cooking processes (boiling, roasting, frying, microwaving) on clenbuterol residues in fortified and incurred tissue was studied. No net change in the amount of clenbuterol was observed in any of the cooking processes investigated except for deep frying using extreme conditions. There was little observed migration from the tissue into the surrounding liquid or meat juices. Clenbuterol residues were found not to be evenly distributed in the incurred raw tissue used for the investigation. The findings of this investigation show that data obtained from measurements on raw tissue are applicable for use in consumer exposure estimates and dietary intake calculations.

Animals↗

Determination of quinoxaline carboxylic acid (metabolite of carbadox) in animal tissue by HPLC.

A method for the determination of residues of quinoxaline-2-carboxylic acid (QCA), the major metabolite of carbadox, in pig kidney has been developed. Tissue samples were subjected to alkaline hydrolysis, liquid-liquid extractions, ion-exchange chromatography and further extraction to concentrate the analyte and purify the extract. Determination was by reverse phase HPLC with UV detection at 320 nm. Validation exercises carried out on batches of six samples fortified with 0.050 mg/kg QCA on three separate days gave mean recoveries ranging from 72 to 79% with relative standard deviations ranging from 5.6 to 7.8%. Samples fortified with 0.010 mg/kg QCA gave a mean recovery of 100% with a relative standard deviation of 9.8%.

Animals↗

The effect of cooking on veterinary drug residues in food: 2. levamisole.

The heat stability of levamisole was investigated. Results obtained indicated that the drug was stable in boiling water at 100 degrees C, but unstable at 260 degrees C in cooking oil, with a half-life of about 5 minutes. The effect of cooking (microwaving, boiling, roasting, grilling and frying) on levamisole residues in a range of fortified and incurred tissue was studied. No evidence of instability was obtained in any of the cooking methods investigated. Most observed net changes fell within the limits of the precision of the method once allowance for weight loss during cooking was made to counter an apparent increase in concentration. Roasting was the only method of cooking where a net loss of levamisole was observed. Insufficient juices were produced to permit analysis in this instance. The net loss of levamisole in the cooked tissue was similar to that found with other cooking methods, where the levamisole lost was found in the cooking liquid or juices. An assessment of homogeneity of the incurred tissue used in the investigation was made. The pig muscle was found not to be homogeneous with larger differences seen between different areas of the animal than within the same muscle. The findings of this investigation showed that data obtained from measurements on raw tissue are suitable for use in consumer exposure estimates and dietary intake calculations.

Animals↗

The effect of cooking on veterinary drug residues in food: 3. Sulphamethazine (sulphadimidine).

The heat stability of sulphamethazine was investigated. The drug was shown to be stable in boiling water at 100 degrees C. In cooking oil at 260 degrees C, losses were observed, indicating a half-life of about 5 min. At 180 degrees C in cooking oil, sulphamethazine was unstable with a half-life of about 2 h. The effect of a range of cooking processes (boiling, roasting, grilling, frying, pressure cooking and microwaving) on sulphamethazine residues in incurred animal tissue was studied. Once allowance for weight loss during cooking had been made no net unaccountable change in concentration of sulphamethazine was observed in any of the cooking processes investigated. During frozen storage, sulphamethazine residues were found to be stable over a period of 3 months. It was found during this investigation that the method used for analysis which involved acid extraction converted the N4-metabolites to parent sulphamethazine, and hence only sulphamethazine was measured. Sulphamethazine was found to be evenly distributed in the raw incurred tissue used for analysis. Migration from the tissue into the surrounding liquid or meat juices was observed during the cooking process. The findings of this investigation show that surveillance data obtained from measurements on raw tissue are applicable for use in consumer exposure and dietary intake calculations, but only if an acidic extraction method which converts the N4-metabolites to parent sulphamethazine is used for the surveillance. This may not however conform to current Maximum Residue Limit legislation which refers to total parent sulphonamides. Different methods of analysis for sulphonamides are likely to give rise to inter-laboratory variation.

Animal Diseases↗

Determination of penicillins in animal tissues at trace residue concentrations: II. Determination of amoxicillin and ampicillin in liver and muscle using cation exchange and porous graphitic carbon solid phase extraction and high-performance liquid chromatography.

A method for the determination of the basic penicillins, amoxicillin and ampicillin, in animal tissue is described. The method used aqueous extraction with tungstate to remove proteins followed by cation exchange solid phase extraction (SPE) clean-up. This extract was further purified using porous graphitic carbon (PGC) SPE. Extracted residues were derivatized with acetic anhydride followed by triazole/mercuric chloride prior to reversed phase HPLC with UV determination at 325 nm. At the Maximum Residue Limit of 50 micrograms/kg in fortified cattle muscle validation gave mean recoveries for amoxicillin of 57% and 50% on two different days with relative standard deviations of 19% and 15% respectively. For ampicillin the recoveries were 72% and 59% with relative standard deviations of 15% and 19% respectively.

Amoxicillin↗

The effect of cooking on veterinary drug residues in food: 7. Ivermectin.

The stability to heat and cooking of ivermectin was investigated. The drug was insufficiently soluble in water to allow the effect of heating in simple aqueous solutions to be studied. The effect of a range of cooking processes was investigated on pig muscle and liver, cattle muscle and liver and salmon muscle. The drug was found to be stable to the effect of cooking. Some leaching of ivermectin with juices as they exuded from the foods as they were cooked was observed; in one case this amounted to about 50% of the total residue.

Animals↗

The evolution of the primate foot from the earliest primates to the Miocene hominoids.

The fossil evidence relating to the evolution of the primate foot is reviewed and evaluated. Many of the characteristic features of the primate foot had evolved by the early Tertiary over 40 million years ago. Probably the most significant of these developments was the progressive migration of the talus to a position over the calcaneum. These morphological features are followed through the Miocene hominoid genera from East Africa, Europe, and South Asia. While some features of Miocene hominoids, especially those relating to climbing abilities, are still evident in the predominantly bipedal earliest hominids of the Plio-Pleistocene, there is no evidence yet from the Miocene of the first stages in the evolution of that bipedalism.

Adaptation, Biological↗