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T Murray

Publications and source records attributed to T Murray.

At least 55 records · Page 3Linked to original sources

The design and construction of a central radiopharmacy.

Following an inspection by the Medicines Control Agency (MCA) of the existing radiopharmacy, it was necessary to design and build a new facility at the Western Infirmary to supply radiopharmaceuticals for patient use throughout the West of Scotland. This is one of the largest radiopharmacies in Europe, supplying some 40,000 patient doses per year prepared using both closed and open procedures. The design parameters and construction details of the new facility are presented.

Facility Design and Construction↗

Elementary Scots. The discovery of Strontium.

The element Strontium takes its name from the village of Strontian in Argyll. It was in ore samples taken from lead mines near the village that Strontium was first identified as a new element in 1970. A radioactive form of the element has reached medical prominence through its use in the palliation of pain in patients with painful skeletal metastases.

History, 18th Century↗

Findings of the 1990 and 1992 student nurse anesthetist survey.

A Student Nurse Anesthetist Survey was sent to each nurse anesthesia educational program in 1990 and in 1992 to assess students' perception of clinical experiences during their training. Two students (one first-year and one second-year student) were selected by each nurse anesthesia program director to represent the program and complete the surveys. The survey included questions directed at such topics as student administration of regional anesthesia, student performance of different techniques of intubation, student placement of invasive lines, and student perception of their overall clinical experiences. The findings indicated that nurse anesthesia students' clinical experiences and perceptions of their clinical experiences were very similar in both 1990 and 1992 for first-year and second-year student respondents.

Attitude of Health Personnel↗

A comparison of the clinical characteristics of first and second primary head and neck cancers. A population-based study.

The clinical characteristics of 183 patients with second primary neoplasms in the head and neck region were compared with those of 20,598 patients with one primary tumor in the same region registered during the period 1973 to 1984 in the Surveillance, Epidemiology and End-Results Program. Second primary head and neck tumors were more likely to be diagnosed in a localized stage (47%) than if diagnosed as a single primary tumor (43%), but this difference was not significant. The tumor grade distribution was comparable in both groups. Using Cox proportional hazards modeling with age, sex, race, and stage as covariates, the median survival of patients with first and second head and neck cancer was identical (50 months). The survival of patients with localized second head and neck cancer was shorter than that of patients with single localized tumors (55 versus 102 months, P less than 0.026). Survival for regional tumors was similar (18 versus 21 months, not significant). The 84 second head and neck cancers in which the first head and neck cancer received radiation therapy (RT) had a median survival of 20 months; the 98 cases without prior RT had a median survival of 35 months. The high incidence of localized second cancers was probably due to the more intense surveillance. The worse survival in this group may be a result of prior RT or biologic characteristics of the tumor.

Carcinoma, Squamous Cell↗

Colorectal cancer: differences between community and geographically distant patients seen at an urban medical center.

Many studies in clinical oncology rely on hospital-derived patients. Hospitals vary in the proportions of patients from the local catchment area vs. those from more distant places, of whom a larger proportion are presumably referrals. To study the differences between these two types of patients, we analyzed 1,245 colorectal cancer patients seen at a large urban medical center over a seven-year period. Three hundred ninety-eight patients were from the local community (32 percent), 489 were from the extended community (39.3 percent), and 358 from more distant communities (28.8 percent). The patients from the local community tended to be older and from minority ethnic groups. In addition, the local community patients were more likely to have advanced disease at the time of presentation. The grade of the tumor and its site distribution within the large bowel were similar for the three groups. After adjusting for age, sex, race, and stage of disease, the survival was somewhat better for the distant community patients as compared with the local and extended communities (P less than 0.02). Overall, in our patient population, the distant patients tended to have more favorable socioeconomic factors and less advanced disease, and these differences may account, in large part, for a better prognosis for these patients. Particularly in large cooperative trials, studies may need to take into account the respective proportions of local community and geographically distant patients in analyzing and generalizing treatment outcomes.

Catchment Area, Health↗

Development of radiolabelled albumin microspheres: a comparison of gamma-emitting radioisotopes of iodine (131I) and indium (111In/113mIn).

Biodegradable albumin microspheres have been prepared incorporating either 131I or 111In/111In. Using cDTPAA/albumin molar ratios of 1, 3 and 10, approx. 0.7, 2.1 and 7 molecules of DTPA could be coupled to an albumin molecule, labelling efficiency being constant over this range. Because 131I microspheres were more stable in plasma than the system labelled with radionuclides of indium it was selected for clinical evaluation: potential uses of this radiopharmaceutical are illustrated.

Biodegradation, Environmental↗

The use of angiotensin II as a potential method of targeting cytotoxic microspheres in patients with intrahepatic tumour.

Cytotoxic microspheres have been developed for intra-arterial use in patients with liver metastases. Following injection, the distribution of microspheres reflects the pattern of hepatic arterial blood-flow. Vasoactive agents, such as angiotensin II, by producing vasoconstriction in normal liver, might divert arterial blood toward tumour and thereby enhance the delivery of drug-loaded particles. Using a double isotope technique, the distribution of radiolabelled microspheres to tumour and normal liver tissue was measured before and after angiotensin II infusion in nine patients with multiple liver metastases. The median increase in tumour: normal ratio following angiotensin II infusion was by a factor of 2.8 (range 0.8-11.7, P less than 0.05). This novel approach to regional chemotherapy, using a combination of angiotensin II infusion and cytotoxic microspheres, increases the exposure of tumour to cytotoxic agents and may, therefore, enhance tumour response rates.

Adult↗

The distribution of alternative agents for targeted radiotherapy within human neuroblastoma spheroids.

This study aims to select the radiopharmaceutical vehicle for targeted radiotherapy of neuroblastoma which is most likely to penetrate readily the centre of micrometastases in vivo. The human neuroblastoma cell line NB1-G, grown as multicellular spheroids, provided an in vitro model for micrometastases. The radiopharmaceuticals studied were the catecholamine analogue metaiodobenzyl guanidine (mIBG), a specific neuroectodermal monoclonal antibody (UJ13A) and beta nerve growth factor (beta NGF). Following incubation of each drug with neuroblastoma spheroids, autoradiographs of frozen sections were prepared to demonstrate their relative distributions. mIBG and beta NGF were found to penetrate the centre of spheroids readily although the concentration of mIBG greatly exceeded that of beta NGF. In contrast, UJ13A was only bound peripherally. We conclude that mIBG is the best available vehicle for targeted radiotherapy of neuroblastoma cells with active uptake mechanisms for catecholamines. It is suggested that radionuclides with a shorter range of emissions than 131I may be conjugated to benzyl guanidine to constitute more effective targeting agents with potentially less toxicity to adjacent normal tissues.

3-Iodobenzylguanidine↗

Serum creatine kinase activity and its changes after a muscle biopsy.

The significance of the absolute elevations of serum creatine kinase (CK) levels after intense exercise and injuries was studied by measuring CK activities from seven healthy active males during a 2-week period, with a muscle biopsy taken between the first and second week. Most of the subjects (three lifters and two runners) carried on their normal exercise activities, while two lifters stopped training during the 2 weeks. The weight of the biopsy, number of fibres, percentage of fibre types, and cross-sectional areas of the muscle fibres were measured. The CK levels of the non-active subjects and runners remained consistently low during the control week, whereas those of the lifters were usually 500% greater than those of the other two groups, and fluctuated with the intensity of their workouts. A muscle biopsy, having a mean weight of 71.3 mg and containing 1800 fibres, increased the CK values by approximately 100 units litre-1 (U l-1) in most of the subjects. One runner injured his right hamstring muscles 2 days prior to the biopsy, and his CK values rose from 50 to 4400 U l-1. The increases in CK after the biopsy were not related to fibre type, activity, weight of the biopsy, or number or size of fibres removed. These results indicate that: (1) CK values are consistently lower in normal subjects and runners than in lifters. (2) Weight training results in chronic elevations of CK. (3) Compared to a muscle biopsy, muscular injury dramatically increases CK levels. (4) Elevation of serum CK is observed as early as 1 h after an intense weight-lifting session.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy, Needle↗

A test of the auricular surface aging technique.

A recently developed technique used in the estimation of age at death is based upon the metamorphosis of the auricular surface of the ilium. This technique was designed to be used in seriation to estimate the age distribution of a skeletal sample. However, the technique has also been used in forensic science cases, which must be analyzed on a case-by-case basis. The present study examines the use of the auricular surface technique as the single aging factor. Two hypotheses are tested using a sample of 189 individuals drawn from the Terry Collection, housed at the Smithsonian Institution. The hypotheses are (1) is the method equally applicable across race and sex, and (2) how well does the method perform as the single aging factor? The results indicate that the amount of degenerative change in the auricular surface is not dependent upon race or sex in any given age category. However, the rate of degenerative change is too variable to be used as a single criterion for the estimation of age; the range of estimation error is simply too large for forensic science purposes.

Adolescent↗

Differential penetration of targeting agents into multicellular spheroids derived from human neuroblastoma.

We have used a multicellular tumour spheroid model for determination of the penetration of various targeting agents of potential use in the treatment of neuroblastoma. Both the radiopharmaceutical meta-iodobenzylguanidine (mIBG) and the beta subunit of nerve growth factor (beta-NGF) distributed uniformly throughout spheroids, though the latter was poorly concentrated relative to mIBG. In contrast, the anti-neuroectodermal monoclonal antibody. UJ13A bound only to peripheral cell layers with little accumulation in the spheroid interior. Differential penetration of targeting agents may influence the choice of conjugated radionuclide which is likely to achieve maximum therapeutic benefit.

3-Iodobenzylguanidine↗

Tumor spheroid model for the biologically targeted radiotherapy of neuroblastoma micrometastases.

Neuroblastoma is a pediatric malignancy with a poor prognosis at least partly attributable to an early pattern of dissemination. New approaches to treatment of micrometastases include targeted radiotherapy using radiolabeled antibodies or molecules which are taken up preferentially by tumor cells. Multicellular tumor spheroids (MTS) resemble micrometastases during the avascular phase of their development. A human neuroblastoma cell line (NBl-G) was grown as MTS and incubated briefly with a radiolabeled monoclonal antibody (131I-UJ13A) directed against neuroectodermal antigens. Spheroid response was evaluated in terms of regrowth delay or proportion sterilized. A dose-response relationship was demonstrated in terms of 131I activity or duration of incubation. Control experiments using unlabeled UJ13A, radiolabeled nonspecific antibody (T2.10), radiolabeled human serum albumin, and radiolabeled sodium iodide showed these to be relatively ineffective compared to 131I-UJ13A. The cell line NBl-G grown as MTS has also been found to preferentially accumulate the radiolabeled catecholamine precursor molecule m-[131I]iodobenzylguanidine compared to cell lines derived from other tumor types. NBl-G cells grown as MTS provide a promising laboratory model for targeted radiotherapy of neuroblastoma micrometastases using radiolabeled antibodies or m-iodobenzylguanidine.

Antibodies, Monoclonal↗

A review of the relationship between coffee consumption and coronary heart disease.

A review of the literature dealing with the relationship between coffee consumption and coronary heart disease revealed that most of the studies did not find coffee consumption to be a risk factor. However, many studies are plagued with methodological difficulties which operate to minimize the probability of identifying coffee consumption as a risk factor. A significant percentage of the studies do not rule out coffee consumption as a significant risk factor in coronary heart disease.

Causality↗

Fifteen years of radiological protection experience in a regional radiopharmacy.

Radiological protection experience in a regional radiopharmacy, currently handling 28.5 TBq (770 Ci) 99mTc y-1, is reviewed for the period 1974-1988. The results of personnel monitoring have shown a downward trend (by more than a factor of two) in radiation exposure of individual staff members, despite the workload per person [6000 GBq (162 Ci) 99mTc y-1] remaining virtually constant. Adequate staff selection and training contribute to the reduction in dose. A significant reduction in dose to the eyes was achieved by installing lead glass screens in the radiopharmacy work stations, and tungsten syringe shields reduced radiation dose to the hands. The use of commercially available kits for producing 99mTc radiopharmaceuticals, rather than relying on in-house preparations that require more operator handling, has also contributed to reduction in radiation exposure. Internal contamination of staff members with 125I was markedly reduced when the practice of sub-dispensing high-specific activity solutions of the radionuclide was discontinued. Annual doses from external radiation currently average less than 6 mSv (600 mrem) to the trunk, less than 7 mSv (700 mrem) to the eyes, and 50 mSv (5 rem) to the hands. Internal contamination of personnel with 125I, 131I, and 99mTc, as detected by thyroid and whole-body monitoring, contributed less than 65 mSv y-1 (6.5 rem) to the thyroid gland and less than 0.1 mSv y-1 (10 mrem) to the whole body.

Humans↗

Investigation of factors affecting adhesion of 99Tcm labelled colloids to glass vials.

Factors which may possibly influence the adhesion of 99Tcm labelled colloid to glass vials were investigated. Of five colloids studied, two protein-free tin colloids were affected most by the problem, some 12-18% being lost by adhesion to the glass vial when the colloid was left resting on the bench, or 60-87% when it was rotated for a period of 4 h. The proportion of activity which adhered to the vial was dependent on the time the product had been contained within it, whether on the bench or rotated. Two of the colloids, both of which contained protein, were affected only slightly by the problem, one being a tin colloid and the other a sulphur colloid. An antimony sulphide colloid, which contained no added protein, was virtually unaffected by the problem. The degree of adhesion was not related to the pH of the product, nor to the temperature at which the product was stored, nor to the tendency of the colloid particles to grow in size upon vigorous agitation.

Colloids↗

Microwave hyperthermia for choroidal melanoma in rabbits.

Radiation has provided excellent local control rates in choroidal melanoma, but significant impairment in visual acuity has occurred in 30-60% of patients due in part to the development of radiation vasculopathy in the fovea and optic disc. Hyperthermia has been shown to have a synergistic effect when added to radiation therapy in human malignancies. The use of hyperthermia in ocular melanoma may allow a reduction in the total radiation dose necessary to achieve local control. A 2450-MHz microwave plaque applicator with integral surface cooling was used to deliver hyperthermia treatments to rabbit eyes containing choroidal melanomas. Extensive thermal mapping was done in acute eyes. In 18 survival animals, a single 23-G needle thermocouple probe with three sensors was inserted into the tumor. Target temperatures of 41.0-46.0 degrees C were maintained for 1 hour. All tumor-bearing eyes were followed for 1 month after treatment, or until tumor growth was noted, with serial ultrasound measurements and visual examinations. A 92% response rate was obtained in tumors treated at temperatures greater than 43.0 degrees C for 1 hour with no significant toxicity. Heat alone has significant tumoricidal properties in this animal model.

Animals↗