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Biomedical subjects

R Trickey

Publications and source records attributed to R Trickey.

6 recordsLinked to original sources
PubMed1999

Myocyte loss in chronic heart failure.

This study examined whether or not there is progressive loss of individual myocytes in established heart failure, accounting for the progressive left ventricular dysfunction; whether such loss is by necrosis or apoptosis; and whether such loss is more pronounced in ischaemic heart disease or idiopathic dilated cardiomyopathy. Tissue for patients undergoing cardiac transplantation for clinical end-stage heart disease was used. The clinical diagnosis was not known to the observer at the time of analysis. Indices of potential myocyte loss were: detection of apoptotic nuclei in situ, using the TUNEL method, immunohistochemistry for CD120a, CD120b, CD95, perforin and granzyme B; binding of C9 complex; and lipofuscin deposition within macrophages. Interstitial macrophages and T cells and their relationship to myocyte loss were also examined. There is indeed low grade myocyte loss in chronic heart failure, but there was no difference between the disease groups; rather, there was marked patient-to-patient variation within each category. Thus in chronic heart failure myocyte loss does occur, and both necrosis and apoptosis contribute to this loss, irrespective of the underlying nature of the disease. Any mechanism which accounts for myocyte loss must be common to both conditions, rather than specific for a pre-operative diagnosis.

Adult↗
PubMed1977

The effect of anti-lipolytic agents on isoprenaline-induced myocardial necrosis in the rat.

The effect of inhibiting isoprenaline-induced lipolysis on the degree of damage produced in the rat myocardium by this amine has been investigated by pre-dosing rats with the anti-lipolytic agent 5-fluoro-nicotinic acid. The degree of myocardial necrosis produced in animals given isoprenaline alone and those pre-dosed with the anti-lipolytic agent was measured by the use of an automated flying spot microscope to show absence of formazan from dead muscle fibres in sections treated to demonstrate succinic dehydrogenase. The use of the anti-lipolitic considerably reduced the degree of myocardial damage produced by a standard dose of isoprenaline bitartrate. This was associated with an inhibition of the post-isoprenaline rise in plasma free fatty acid levels. The results are discussed in relation to the possible protective roles of the lowering of plasma free fatty acid levels and inhibition of the adenyl cyclase system at the plasma membrane of the myocardial cell produced directly by the anti-lipolytic.

Animals↗
PubMed1976

Muscle changes in acromegaly.

Muscle biopsy specimens were obtained from 18 patients with acromegaly of varying degrees of severity. Half the specimens showed hypertrophy of type 1 fibres, while atrophy was most often seen in type 2 fibres. A direct correlation between muscle appearances and growth hormone levels was not observed. The needle biopsy technique is particularly suitable for determining the natural history of acrometalic myopathy.

Acromegaly↗
PubMedDate not supplied

Histological investigations into the relationship between low birth weight and spontaneous bowel damage in the neonatal piglet.

Experimental models for the study of neonatal necrotizing enterocolitis (NEC) using the small for gestational age (SGA), viable, term-delivered piglet have recently been described. A spontaneous model, especially of the early phases of NEC, has not been reported. Pig litters usually include one or two lethally or sublethally SGA "runted" piglets culled from the litters by breeders. We have examined four groups of piglets: group A, SGA, lethally runted animals who died spontaneously before 12 h postpartum; group B, SGA, sublethally runted animals, showing some signs of vitality and left alive for 24 h before culling; group C, appropriate for gestation age (AGA) animals subjected to hypoxia and hyperviscosity known to induce NEC-like lesions; and group D, AGA control animals. Acute, multiorgan pathology common to pre- and dysmature neonates was seen in groups A and B. Animals in group B also showed evidence of early postnatal complications such as urinary tract infection and diffuse pulmonary damage. All animals of groups A and B showed unequivocal early changes in the distal ileum, with mucosal and submucosal necrosis, suggestive of ischemic injury. One animal in group B had developed mural necrosis involving the whole of the submucosa. No similar changes were seen in control group D animals. The very-SGA, lethally and sublethally runted, spontaneously term-delivered piglet offers sufficient spontaneous early NEC-like changes for studies of the early pathogenesis of this condition.

Animals↗