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Biomedical subjects

A C Lopes

Publications and source records attributed to A C Lopes.

At least 37 records · Page 2Linked to original sources
PubMed1979

[Some ultrastructural aspects of the cardiac muscle of albino rat during the acute stress produced by formaldehyde (author's transl)].

The authors studied ultrastructurally the influence acute stress, produced by formaldehyde, has on some aspects of the cardiac muscle metabolism in albino rats. The results showed that the cardiac muscle was induced to develop additional work, represented ultrastructurally by an increase in the number of lipid droplets and increased concentration and volume of mitochondria.

Acute Disease↗
PubMedDate not supplied

Anatomical and clinical aspects of the blood supply of the sinoatrial node.

BACKGROUND: The recent study of the variations of the origin of the sinoatrial node and on the "arterial network of the perinodal sinusal area" in normal hearts points out the importance of this network. PURPOSE: Report on a case of patient with syncope of ischemic etiology. CONCLUSION: In this patient the arterial network did not protect the node from the ischemia caused by the obstruction of the artery of the sinoatrial node.

Coronary Vessels↗
PubMedDate not supplied

[Ultrastructural features of cardiac muscle fibers of albino rats during the pregnancy and puerperal cycle].

PURPOSE: In the present study we evaluated the morphology of left ventricular cardiomyocytes of albino rats during pregnancy and puerperium by means of transmission electron microscopy. METHODS: Once pregnancy was confirmed, 77 rats were randomly divided in two groups, respectively, gestation (G) and puerperium (P). The animals of the gestation group were divided into four subgroups, according to gestational age: 1st (G-A), 7th (G-B), 14th (G-C) and 21st (G-D) days of pregnancy. The group defined as puerperium was divided into three subgroups: 7th (P-A), 14th (P-B) and 21st (P-C) days of puerperium. In the end of each established period, the animals were sacrificed and fragments of the medium third of the left ventricle were resected and routinely prepared for electron microscopy analysis. RESULTS: The results obtained with transmission electron microscopy analysis revealed a gradative increase of the cardiomyocytes during pregnancy (increase of myofibrils, which are permeated by numerous mitochondria at the end of gestation). The blood capillary wall showed progressive thinning, with an increase of pynocytotic vesicles in endothelial cells, and intense sarcolemal folding at T-tubule level (capillary tunnels). In the puerperium group, there is a progressive regression in these alterations returning to pre-gestational level at the end of the puerperium cycle. These findings indicate the occurrence of hypertrophy of cardiomyocytes during pregnancy. CONCLUSION: The findings indicate the occurrence of hypertrophy of cardiomyocytes during pregnancy.

Adaptation, Psychological↗
PubMedDate not supplied

[Histomorphometric study of cardiomyocytes of the left ventricle of pregnant albino rats].

PURPOSE: In the present study we evaluated, by light microscopy, and throughout morphometry, whether hypertrophy of cardiac striated muscular fibers of left ventricular occur in albino rat, during pregnancy. METHODS: After maiting, 12 nuliparous rats were divided into four groups with three animals for each group. The female rats corresponding to each group were killed at 1st, 7th, 14th and 21st days of pregnancy. RESULTS: Observation, on light microscopy (H.E) had at one view, did not display any alterations during pregnancy. However, the morphometry revealed that nuclei of cardiomyocytes are augmented in volume at 14th day of pregnancy and statistically significant data show the hypertrophy. CONCLUSION: The obtained data show the existence of a dinamic and reversible process of ventricular remodelling in consequence of adaptation physiological alterations of the cardiovascular normal pregnancy.

Animals↗