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Biomedical subjects

C Velican

Publications and source records attributed to C Velican.

138 records · Page 8Linked to original sources
PubMedDate not supplied

The branching anatomical pattern of the coronary arteries as a risk factor for coronary heart disease.

In an unselected population sample of Bucharest aged 0-45 years, a similar branching anatomical pattern of the coronary arteries was revealed in 58% of the subjects. In the remainder 42% of cases 15 different minor deviations from the basal branching anatomical pattern were detected. Among these minor deviations, 4 occurred constantly associated, 8 only occasionally associated (1/3-1/2 of cases) and 3 were not associated with an accelerated atherosclerosis. The "atherogenic" deviations, characterized by an excessive size and length of the left coronary artery and an underdeveloped right coronary artery or vice versa, led to a more precocious development and more severe evolution of atherosclerotic plaques in the hyperperfused vessel.

Adolescent↗
PubMedDate not supplied

Transintimal clefts or "channels" of normal and atherosclerotic coronary arteries (a preliminary study).

Transintimal clefts or "channels" have been found in the coronary arteries of children, adolescents, young and mature adults up to 40 years old; they appeared on light microscope examination as sinusoid-like spaces running from the endothelium to the internal elastic membrane. The mean luminal diameter was 5-6 micrometers, and the maximum density per mm2 varied between 15 (anterior descending artery) and 3 (left main coronary artery). Transintimal clefts or "channels" developed as cylindrical tunnels into the intimal connective tissue surrounded by a coat of ground substance rich in heparan sulfate; blood red cells, leucocytes and platelets were not present in their lumen. In serial cross-sections and camera lucida drawings transintimal "channels" appeared as blind tubes ending either in the inner or outer half of the thickened intima or at the intima-media frontier. We were unable to reveal connections with media vasa vasorum. Atherosclerotic plaques undergoing a mucoid transformation or submitted to swelling and/or dissecting necrosis occurred constantly connected with the coronary artery lumen by transintimal "channels". Many light microscopic pictures suggested that the necrotizing agent(s) of plasma spreads along the course of transintimal "channels" and reached the basal intimal regions or the basal areas of developing and preexisting atherosclerotic plaques. The implications of the presence of transintimal clefts or "channels" in the pathogenesis of human atherosclerosis are discussed.

Adolescent↗
PubMedDate not supplied

Method dependent limits in a study on the natural history of coronary and cerebral atherosclerosis.

Important discrepancies were revealed in a study on human coronary and cerebral atherosclerosis among data furnished by gross inspection and by light microscopy. The character of atherosclerotic lesions, the meaning of the terms "normal intimas" "fatty streaks", "fibrous plaques" and "complicated lesions", the type of the early atherosclerotic lesions, the age period of the onset of these early lesions, their sequence of development, their relationship to advanced lesions--all appeared method dependent. The gross inspection alone led not only to an oversimplified, but also to a distorded view on the natural history of atherosclerosis, since it overlooked the role of intimal necrosis, incorporated microthrombi, fibromuscular plaques, mucoid plaques and foam cell-rich plaques in atherogenesis. The degree and extent to which the early stages of atherosclerotic involvement remained undetected by gross inspection was surprisingly great. The difference between the number of atherosclerotic plaques recorded on microscopic and macroscopic examination of the same vascular segments was statistically significant (p less than 0.01). Our results suggest that all basic studies of human atherosclerosis must include intermingled macroscopic and microscopic examination of the same arterial segments and require the use of an adequate terminology.

Adolescent↗
PubMedDate not supplied

Preliminary study on the natural history of cerebral atherosclerosis.

Using the gross dissection and microscopic examination of intracranial arteries of 384 subjects aged 0-70 years from an unselected population sample of Bucharest, the period of life in which the first atherosclerotic plaques and fatty streaks occurred in male and female subjects was delineated. The prevalence (%) of cases with atherosclerotic plaques in successive age groups in also presented. In the anterior cerebral arteries the onset of the first atherosclerotic plaques lag behind the basilar artery by a 10-year period. The male to female ratio of positive cases with atherosclerotic plaques was statistically significant for the basilar artery and non significant for the anterior cerebral arteries. On an age-group basis, the atherosclerotic plaques of the basilar artery were constantly and significantly more obstructive than those of the anterior cerebral arteries.

Adolescent↗
PubMedDate not supplied

The gelatinous plaque: its relation to coronary atherosclerosis.

The relations between the gelatinous plaque and the atherosclerotic plaque were investigated on more than 500 subjects aged 1--40 years. The appearance of the light microscopic aspect of the gelatinous plaque was related to a particular: a) evolution of the process of histolysis involving branch pads and thickened intimas; b) insudation, occurring in nodular proliferations of intimal smooth muscle cells; c) stage of atheroma formation. The results showed that the term gelatinous plaque did not refer to an independent, early atherosclerotic lesion, or a true precursor of advanced lesions,but to an intermediate, transitional stage in the complex histogenesis of the atherosclerotic plaque.

Adolescent↗
PubMedDate not supplied

Sex differences in age- and atherosclerosis-related changes of human coronary arteries.

A study carried out on the coronary arteries of 536 subjects ranging in age from 0 to 40 years demonostrated that males exhibited, as compared to females of similar age: more numerous and extensive severe changes of the internal elastic membrane, particularly in neonates and children; a thicker intimal layer in all age-groups investigated; an earlier development of atherosclerotic plaques and of atheroma-like lesions; a higher number of cases with coronary atherosclerotic plaques; a more precocious and diffuse extension of atherosclerotic plaques in the whole coronary tree.

Adolescent↗
PubMedDate not supplied

Coronary arteries in children up to the age of ten years II. Intimal thickening and its role in atherosclerotic involvement.

The frequency, histologic feature and topographic distribution of the first foci of intimal thickening were investigated in the coronary arteries of 40 fetuses, 40 neonates and 90 children up to the age of ten years. Particular hemodynamic and mechanical stresses seem to be involved in the precocious development of these isolated foci of intimal thickening which appeared in the early fetal life as well as in their progressive extension and fusion which give rise to diffuse thickened intima. After birth the stressed areas with thickened intima might evolve toward fibrosis and the "protected" ones toward degenerative and necrotic processes. These processes were detected in approximately 8% of the 5-10 year-old children and appeared before the development of fatty streaks or other forms of lipid accumulation.

Age Factors↗
PubMedDate not supplied

Structural peculiarities in developing coronary arteries located in the epicardial connective tissue.

A striking difference was observed in the coronary bed between the histogenesis of the main stem vessels and that of their branches. The developing main stem vessels exhibited the structural pattern of arteries submitted to intense hemodynamic stresses, whereas the developing branches showed the structural pattern of arteries protected against these stresses. This striking difference was related, histologically, to the existence of sphincteral mechanisms located in all the branching points present in both right and left coronary arteries.

Adolescent↗
PubMedDate not supplied

Intimal histolysis as an early stage of atherosclerotic involvement. Observations on the human coronary arteries.

Investigation of the coronary arteries in 330 subjects aged 11 to 50 years showed that the "missing link" between age-dependent changes and atherosclerotic lesions appeared as a process of intimal histolysis. This term refers to focal disintegrations of the intimal connective tissue involving successively ground substance, reticular networks, collagen fibers, elastic fibers and smooth muscle cells. The resulting gelatinous plaques and detritus cavities represent the starting point for the development of fibrous plaques with or without necrotic centers (atheroma).

Adolescent↗