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Biomedical subjects

W M Allen

Publications and source records attributed to W M Allen.

At least 19 recordsLinked to original sources
PubMed2003

Liver-related biochemical changes in the serum of dogs being treated with phenobarbitone.

The concentrations of phenobarbitone, albumin, bile acids and cholesterol, and the activities of alkaline phosphatase (AP), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT) and glutamate dehydrogenase (GLDH) were measured in the serum of 95 epileptic dogs whose clinical signs were controlled with phenobarbitone. The dogs were divided into groups on the basis of the concentration of phenobarbitone in their serum, the dose administered and the duration of the treatment. The concentration of phenobarbitone in serum was directly related to the activities of ALT, AP, GGT and GLDH and inversely related to the concentration of albumin. There was no significant relationship between the duration of treatment and the serum concentration of phenobarbitone, but there was a significant relationship between the duration of treatment and the activities of ALT, AP and GLDH. Thirty-five of the dogs (37 per cent) had serum activities of AP above the normal range, 19 had abnormally high activities of ALT, and 15 had high activities of GLDH, but these incidences were not related to the serum concentration of phenobarbitone. The dogs receiving higher doses for longer periods had the highest incidence of high activities of AP, ALT and GLDH. The concentration of bile acids in seven of the dogs was above the normal range but there was no relationship between the concentration and either the serum concentration, dose or duration of treatment with phenobarbitone.

Alanine Transaminase↗
PubMed1999

Benign metastasizing leiomyoma of the uterus: histologic and immunohistochemical characterization of primary and metastatic lesions.

Benign uterine leiomyoma metastasizing to the lung is a recognized entity that has been reported infrequently in the medical literature. There is persisting controversy regarding the pathogenesis and biology of these lesions. We report a well-studied and well-characterized case of benign leiomyoma metastasizing to the lung. The patient was a 72-year-old woman with an enlarged uterus that contained several leiomyomas with usual histology. Areas of fibrosis, hyalinization, edema, and focal infarction together with small foci with mildly increased cellularity and minimal nuclear pleomorphism were seen. Careful and repeated mitotic counts ranged from 0 to 2 mitoses per 10 high-power fields. In summary, based on histopathologic criteria, the neoplasm was determined to be a focally cellular benign leiomyoma. Four years later, the patient underwent surgical resection of a single nodule in the lung, which had been detected on routine radiographs. Histopathologic evaluation showed a low-grade leiomyosarcoma with moderate nuclear pleomorphism, necrosis, and brisk mitotic activity. Immunohistochemical studies performed on both neoplasms showed them to be of mesenchymal derivation with smooth muscle differentiation. Both neoplasms expressed estrogen receptors with moderate to strong intensity. The patient received no further treatment and, to date, shows no evidence of recurrent disease. The diagnosis of benign metastasizing leiomyoma can only be made with certainty after careful and extensive sampling of the primary tumor to exclude small foci of sarcoma and of the pulmonary tumor to rule out a primary neoplasm. Although it is biologically peculiar, benign metastasizing leiomyoma should continue to be recognized as a distinct entity because current morphologic criteria do not allow primary myometrial tumors to be reclassified as leiomyomas of uncertain malignant potential even if they have metastasized to the lung.

Actins↗
PubMed1989

Accidental contamination of the public water supply at Lowermoor, Camelford: an assessment of the possible veterinary consequences.

As a result of the delivery of 20 tons of concentrated aluminum sulphate solution into the wrong part of the Lowermoor water treatment works the water supplies of 20,000 people and many thousands of cows, sheep, pigs and poultry became contaminated with aluminium, copper, zinc and lead. When the water mains were flushed into the rivers Allen and Camel many fish were killed by the high concentrations of aluminium. However, there appear to have been no detrimental effects on farm live-stock; this was either because the animals were likely to have ingested less of the toxic elements from the water than they ingest with normal components of their diet, including soil, or because the abnormally high intakes lasted for only a short time.

Alum Compounds↗
PubMed1985

Barium selenate injections in cattle: effects on selenium concentrations in plasma and liver and residues at site of injection.

Twenty Angus cross heifers were fed a complete diet which contained 0.07 mg selenium/kg dry matter. Thirteen were injected subcutaneously with barium selenate at a dose rate of approximately 1 mg selenium/kg bodyweight and seven remained untreated. All the heifers were slaughtered during the following 121 days, the last of the treated group 119 days after injection. Glutathione peroxidase activity in blood increased within four weeks of administration and remained high thereafter. The selenium dependent glutathione peroxidase activity did not increase in liver kidney or muscle. The concentrations of selenium in the blood, liver and muscle were increased significantly from 30 days until 119 days. Between 76 and 99 per cent of the selenium injected remained at the site of injection.

Animals↗
PubMed1985

Boluses of controlled release glass for supplementing ruminants with cobalt.

Boluses of controlled release glass containing cobalt and weighing approximately either 60 g or 14.5 g were administered to 22 steers and 21 sheep respectively. The steers were housed and slaughtered at intervals between 17 and 145 days after dosing. The boluses released more than 0.85 mg cobalt daily. In both untreated and dosed animals serum and liver vitamin B12 concentrations were at the upper end of the normal range. Two types of glass were administered to sheep. In five wethers one glass released 0.07 mg cobalt per day, and in 16 grazing lambs a second glass released more than 0.15 mg cobalt per day. Fourteen of the boluses were recovered from the lambs up to 276 days after dosing. The concentration of B12 in serum of lambs increased significantly from a mean +/- sd of 1.64 +/- 0.47 to 2.02 +/- 0.04 ng/ml serum and the concentration in liver from 3.84 +/- 0.85 to 4.99 +/- 0.72 micrograms/g dry weight liver.

Animal Feed↗
PubMed1985

Myxoid degeneration of the aortic valve and isolated severe aortic regurgitation.

Clinical and pathologic data were reviewed in 55 patients who had valve replacement for pure aortic regurgitation (AR) during a 6-year period. The clinical histories established the cause for AR in 34 cases: 11 rheumatic, 13 infective endocarditis, 4 congenital, 4 associated with aortic aneurysms and 2 the Marfan syndrome. In the valves from the other 21 patients, 13 had myxoid degeneration, defined as significant disruption of the valve fibrosa and its replacement by acid mucopolysaccharides and cystic change. Myxoid degeneration was also the primary pathologic abnormality in the 2 patients with the Marfan's syndrome, in 3 patients with a history of rheumatic disease and in 1 patient with a history of infective endocarditis. The patients with myxoid degeneration of uncertain origin were predominantly elderly (average age 63 years), had a long-standing history of systemic hypertension (77%) and had coronary artery disease (46%); 85% were male. In these patients the replacement valves were not larger than those of the other groups studied, indicating that dilatation of the aortic anulus was not a significant factor in the pathogenesis of the valve disease. These findings indicate that myxoid degeneration of the aortic valve is common (36% of all valves examined) and, in many cases, may be secondary to long-standing systemic hypertension.

Adolescent↗
PubMed1985

The use of controlled-release glass for the controlled delivery of bioactive materials.

CRG can provide a useful supplement to other methods of controlled delivery. Some advantages of this approach are: The constituents of the CRG can be limited to biologically safe ionic species such as Na+, Ca2+ and PO4(3-). The release system is completely soluble in water and no residue remains. There is no evidence of any mechanism for biodegradation of the CRG and so one possible cause of premature or accelerated release is eliminated. The absolute release rate can be selected anywhere in a spectrum covering several orders of magnitude and the rate-controlling process has zero-order kinetics. The release rate can be selected to be pH-sensitive or pH-independent. Complex temporal release-rate patterns can be obtained readily by the choice of geometrical shape or composition profile of the device. The controlled release of organics or other heat-sensitive materials which cannot be incorporated in the glass can be realized by the use of composite structures in which the CRG is the rate-controlling constituent. A number of different functions can be performed by a single CRG-based device. For example, CRG can be used as a biomedical resorbable material in surgery and the CRG structural component can release an AM as it dissolves. Similarly the CRG of the sinter-composite used for organic AM release can itself release any selected inorganic adjuvant. CRG boluses containing either copper or cobalt and weighing approx. either 70 g or 15 g, have been administered to both cattle and sheep. More than 90% of the boluses remained either in the reticulum of trace element remained after dosing.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

Reaction cements as materials for the sustained release of trace elements into the digestive tract of cattle and sheep. I. Copper release.

Acid-base reaction cements were produced by reacting copper oxide with phosphoric acid. When placed in the reticulo-rumen of cattle and sheep these cements released copper into the digestive tract for at least 3 months at a rate sufficient to provide the animals' requirements for copper. Lambs given a pellet of cement at 3 months of age had significantly greater concentrations of copper in their livers than similar untreated animals when slaughtered 3-4 months later. It was shown that salts of cobalt and selenium could be incorporated into the cement to provide additional supplementation with these two elements.

Animals↗
PubMed1985

An aviator with idiopathic dilated cardiomyopathy.

The clinical presentation, evaluation and diagnosis of an aviator with dilated cardiomyopathy of determined etiology are discussed. The aeromedical disposition and prognosis of this patient are also presented.

Adult↗
PubMed1984

Boluses of controlled release glass for supplementing ruminants with copper.

A controlled release glass was formulated into boluses weighing approximately 17 g or 75 g and administered to 19 lambs and 20 steers respectively. The animals were at pasture during the summer months. The lambs were slaughtered between 57 and 219 days after dosing when the mean concentration of copper in their livers had increased to 107.8 +/- 33.4 mg copper/kg fresh weight compared with 55.9 +/- 23.0 mg copper/kg fresh weight in undosed controls. The steers were slaughtered more than 140 days after dosing; the mean concentrations of copper in plasma had increased and the mean concentration of copper in liver was significantly greater than in undosed control steers (14.1 +/- 4.8 mg copper/kg fresh weight liver in dosed steers, 4.7 +/- 1.4 mg copper/kg in control steers) and was similar to the concentration in steers which had received 200 mg copper as copper calcium edetate (18.2 +/- 4.2 mg copper/kg fresh weight). In sheep the minimum rate of release of copper into the reticulorumen was 2.1 mg/day and in steers 11 mg/day.

Animal Nutritional Physiological Phenomena↗