Ultrastructural characteristics of the vascular wall components of ruptured atherosclerotic abdominal aortic aneurysm

The aim of this study was to determine the ultrastructural characteristics of cell populations and extracellular matrix components in the wall of ruptured atherosclerotic abdominal aortic aneurysm (AAA). We analyzed 20 samples of ruptured AAA. For orientation to the light microscopy, we used routine histochemical techniques by standard procedures. For ultrastructural analysis, we applied transmission electron microscopy (TEM). Our results have shown that ruptured AAA is characterized by the remains of an advanced atherosclerotic lesion in the intima followed by a complete absence of endothelial cells, the disruption of basal membrane and disruption of internal elastic lamina. On plaque margins as well as in the inner media we observed smooth muscle cells (SMCs) that posses a euchromatic nucleus, a well-developed granulated endoplasmic reticulum around the nucleus and reduced myofilaments. The remains of the ruptured lipid core were acellular in all samples; however, on the lateral sides of ruptured plaque we observed a presence of two types of foam cells (FCs), spindle- and star-shaped. Fusiform FCs possess a well-differentiated basal lamina, caveolae and electron dense bodies, followed by a small number of lipid droplets in the cytoplasm. Star-shaped FCs contain a large number of lipid droplets and do not possess basal lamina. On the inner margins of the plaque, we observed a large number of cells undergoing apoptosis and necrosis, extracellular lipid droplets as well as a large number of lymphocytes. The media was thinned out with disorganized elastic lamellas, while the adventitia exhibited leukocyte infiltration. The presented results suggest that atherosclerotic plaque in ruptured AAA contains vascular SMC synthetic phenotype and two different types of FCs: some were derived from monocyte/macrophage lineage, while others were derived from SMCs of synthetic phenotype. The striking plaque hypocellularity was the result of apoptosis and necrosis of different cell populations

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy with severe factor XII deficiency

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited adult-onset microangiopathy caused by missense mutations in the Notch3gene on chromosome 19. However, common vascular risk factors may additionally modify clinical expression and progression of the disease. The role of various prothrombotic factors has also been implied. We report a case of a middle-aged man with typical clinical, neuroimaging and histological features of CADASIL, but with notably prolonged activated partial thromboplastin time. Hematological investigations revealed severe clotting Factor XII deficiency. This case illustrates that the occurrence of vascular risk factors should not be overlooked in patients with CADASIL

Ultrastructural characteristics of the vascular wall components of ruptured atherosclerotic abdominal aortic aneurysm

The aim of this study was to determine the ultrastructural characteristics of cell populations and extracellular matrix components in the wall of ruptured atherosclerotic abdominal aortic aneurysm (AAA). We analyzed 20 samples of ruptured AAA. For orientation to the light microscopy, we used routine histochemical techniques by standard procedures. For ultrastructural analysis, we applied transmission electron microscopy (TEM). Our results have shown that ruptured AAA is characterized by the remains of an advanced atherosclerotic lesion in the intima followed by a complete absence of endothelial cells, the disruption of basal membrane and disruption of internal elastic lamina. On plaque margins as well as in the inner media we observed smooth muscle cells (SMCs) that posses a euchromatic nucleus, a well-developed granulated endoplasmic reticulum around the nucleus and reduced myofilaments. The remains of the ruptured lipid core were acellular in all samples; however, on the lateral sides of ruptured plaque we observed a presence of two types of foam cells (FCs), spindle- and star-shaped. Fusiform FCs possess a well-differentiated basal lamina, caveolae and electron dense bodies, followed by a small number of lipid droplets in the cytoplasm. Star-shaped FCs contain a large number of lipid droplets and do not possess basal lamina. On the inner margins of the plaque, we observed a large number of cells undergoing apoptosis and necrosis, extracellular lipid droplets as well as a large number of lymphocytes. The media was thinned out with disorganized elastic lamellas, while the adventitia exhibited leukocyte infiltration. The presented results suggest that atherosclerotic plaque in ruptured AAA contains vascular SMC synthetic phenotype and two different types of FCs: some were derived from monocyte/macrophage lineage, while others were derived from SMCs of synthetic phenotype. The striking plaque hypocellularity was the result of apoptosis and necrosis of different cell populations

Effect of Low Temperature Cultivation on Insulin Secretory of Human Pancreatic Islets

The experiment compared the physiological function (insulin secretory capacity) and membrane integrity of human adult pancreatic islets incubated in culture at 37 degrees C and 24 degrees C. Pancreatic tissue was digested with Collagenase XI, using a non-automated method. Cultures were incubated at 37 degrees C and 24 degrees C. Secretory capacity of the islets is determined by measuring of the stimulation index (SI) on the 3rd and 7th day of cultivation. Membrane integrity of the islets was determined by dithizone staining. Both groups of examined cultures show a slight increase in SI during the incubation. However islets incubated at 24 degrees C show higher SI values than those incubated at 37 degrees C on the 1st, 3rd and 7th day of incubation. And on the first day of incubation, this difference was statistically significant (p LT 0.05). Islets incubated at 37 degrees C showed preservation of membrane integrity, the islets are regular spherical shape, while those incubated at 24 degrees C lose such an organization. During the seven-day cultivation, islets incubated at a standard temperature of 37 degrees C show less preserve physiological functions in relation to cultures incubated at 24 degrees C, but islets incubated at 37 degrees C show more regular morphological forms

Effect of Low Temperature Cultivation on Insulin Secretory of Human Pancreatic Islets

The experiment compared the physiological function (insulin secretory capacity) and membrane integrity of human adult pancreatic islets incubated in culture at 37 degrees C and 24 degrees C. Pancreatic tissue was digested with Collagenase XI, using a non-automated method. Cultures were incubated at 37 degrees C and 24 degrees C. Secretory capacity of the islets is determined by measuring of the stimulation index (SI) on the 3rd and 7th day of cultivation. Membrane integrity of the islets was determined by dithizone staining. Both groups of examined cultures show a slight increase in SI during the incubation. However islets incubated at 24 degrees C show higher SI values than those incubated at 37 degrees C on the 1st, 3rd and 7th day of incubation. And on the first day of incubation, this difference was statistically significant (p LT 0.05). Islets incubated at 37 degrees C showed preservation of membrane integrity, the islets are regular spherical shape, while those incubated at 24 degrees C lose such an organization. During the seven-day cultivation, islets incubated at a standard temperature of 37 degrees C show less preserve physiological functions in relation to cultures incubated at 24 degrees C, but islets incubated at 37 degrees C show more regular morphological forms