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Biomedical subjects

T Cairns

Publications and source records attributed to T Cairns.

At least 73 records · Page 4Linked to original sources
PubMed1984

Halo-body device.

A halo-body system is described which has been developed at Princess Margaret Rose Orthopaedic Hospital in Edinburgh. The system is easy to apply and consists of a standard halo, linked to malleable plates by two hollow vertical rods. These rods are connected to the ring by swivel joints which allow for the movements of flexion and extension. The malleable plates are incorporated into the plaster jacket which rests upon the iliac crests. The results of 13 patients who have had this system applied are discussed and include patients who have sustained fractures of the cervical spine or who have had bone destruction from metastatic disease or from infection. Using this type of system there have been few complications and the patients have benefitted from easy mobilisation.

Cervical Vertebrae↗
PubMed1983

Liquid chromatography mass spectrometry of dexamethasone and betamethasone.

Chemical ionization mass spectra of dexamethasone and betamethasone have been obtained via liquid chromatography mass spectrometry using a moving belt interface. These results have confirmed a concentration-dependent competition between thermal degradation and vaporization. Caution should be exercised when dealing with molecules subject to thermal instability since sample introduction via the mechanical transport system does not guarantee evaporation without thermal decomposition.

Betamethasone↗
PubMed1983

Application of mass spectrometry in the regulatory analysis of pesticides and industrial chemicals in food and feed commodities.

During regulatory analysis of pesticides and industrial chemicals, compounds are frequently encountered which cannot be readily identified by gas chromatography alone on two or more stationary phases. Such incurred unknown analytical responses are examined by gas chromatography mass spectrometry, particularly if they have been shown to contain P, S, N or halogen via specific gas chromatography detectors. Seven case histories are presented to illustrate the analytical approach adopted to structurally elucidate such compounds at the ppm level. These examples demonstrate the potential complementary combination provided by low resolution electron impact and chemical ionization mass spectrometry in structural determinations.

Animal Feed↗
PubMed1982

Antibody to Ebola virus in guinea pigs: Tandala, Zaire.

A case-control study was conducted to investigate the findings of antibody to Ebola virus in the serum of a guinea pig from Tandala, Zaire. Case households, defined by the possession of one or more guinea pigs, were compared to neighboring households without guinea pigs. Seven (5.1%) of 138 samples of human sera and 36 (26%) of 138 samples of guinea pig sera had antibody to Ebola virus. There was no clustering of seropositivity among humans or guinea pigs within households, nor was there any association between the ownership of guinea pigs and seropositivity among household members. These data suggest sporadic subclinical infection of guinea pigs and humans without a dominant role for person-to-person or guinea pig-to-guinea pig transmission.

Animals↗
PubMed1981

Chemical ionization mass spectrometric examination of metabolized toxaphene from milk fat.

Gas chromatographic mass spectrometric techniques using methane chemical ionization have been employed to characterize the chemical composition of Toxaphene reference material, as well as the metabolized residue in milk fat resulting from controlled administration to cows. The results indicated that selection of particular ions can be of great value in determining whether or not an observed residue by electron capture should be attributed to a metabolized residue of Toxaphene. Analysis of six commercial milk samples by electron capture gas chromatography and gas chromatography mass spectrometry/chemical ionization/selected ion monitoring has provided semi-quantitative data for comparison of the determinative step.

Animals↗
PubMed1980

Review of the dioxin problem. Mass spectrometric analyses of tetrachlorodioxins in environmental samples.

Major concern over the chemical group of chlorodioxins has arisen since 2,3,7,8-tetrachlorodibenzo-p-dioxin with its extremely toxic and teratogenic properties has been found in widely distributed pesticides such as the herbicide 2,4,5-trichlorophenoxy acetic acid. Because of its chemical stability and lipophilic nature, 2,3,7,8-tetrachlorodibenzo-p-dioxin released into the environment has the potential of accumulation in the food chain. Mass spectrometry in its various forms has been the method of choice to detect and confirm low parts per billion of 2,3,7,8-tetrachlorodibenzo-p-dioxin. Recently, a Consensus Forum held at the National Center for Toxicological Research amongst the various United States Government agencies (Food and Drug Administration, Environmental Protection Agency, US Department of Agriculture and National Institute of Environmental Health Sciences), eloquently demonstrated the potential, as well as the shortcomings, of the various techniques applied. In particular, the availability of a stable 13C labeled 2,3,7,8-tetrachlorodibenzo-p-dioxin has proved to be an essential component to achieve low level quantitation. A brief review of the findings of the Consensus Forum is presented together with a detailed survey of the application of atmospheric pressure ionization mass spectrometry to TCDD analysis at the National Center for Toxicological Research/Food and Drug Administration.

Animals↗
PubMed1980

A toxicological risk assessment procedure: a proposal for a surveillance index for hazardous chemicals.

Health-oriented government agencies responsible for the protection of the public from possible adverse effects, such as that posed by chemical residues in the food supply, must establish priorities on regulatory action as well as for manpower to conduct monitoring programs. A new procedure entitled Surveillance Index (SI) is presented as a technique to evaluate toxic materials that are potential candidates as residues in food supplies and to assign an index number that identifies a relative hazard to the public among the various residues. The SI numbers can be used as criteria by which chemical residues should be monitored whenever conditions such as time and available resources are limiting factors.

Chemical Industry↗