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O Eliska

Publications and source records attributed to O Eliska.

At least 19 recordsLinked to original sources
PubMed2006

[Purkynje fibers of the heart conduction system--history and the present time].

It has been 160 years now since Purkynje published the finding of conduction fibers in the heart in Archiv f. Anatomie u. Physiologie and it has been 166 years since his publication in polish version. Already during Purkynje's life, some anatomists had solved the morphology of these fibers but nobody at that time knew of what great physiological and medical importance this discovery would be for medicine. It was seen as late as in the 20th century and in contemporary times. Purkynje's work indicated the cascade of these discoveries, which were leading in the beginning of the previous century to the formulation of the basic scheme of the conduction system. Purkynje fibers or Purkynje cardiomyocytes are part of the whole complex of the cardiac conduction system which today is classified as specific heart muscle tissue, being responsible for the generation of the heart impulses. From the point of view of ultrastructural composition, the cells of different parts of the cardiac conduction system are partly similar. In contrast to the heart contractile cardiomyocytes, the cells of the cardiac conduction system including Purkynje fibers have a small amount of myofibrils,small mitochondrias, light cytoplasm and a higher glycogen content, but no T-tubular system. They can be detected with some morphological methods. Nevertheless the cells of the conduction system are not completely uniform. They differ in size, number of nexuses-gaps and intercalar discs in individual parts of the conduction system. Nevertheless, these specialized cells work as a whole-unit. Nowadays, the morphology research of all the parts of cardiac conduction system, including Purkynje fibers, is focused on ultrastructural, histochemical and genetical problems. The question is, wheather with future gene/cell therapy disturbances of the conduction system such as arrythmias, can be prevented and cured by replacing the electrical pacemakers with biological ones. If Jan Evangelista Purkynje lived today, he would be surprised but surely delighted with the high degree of research concerning his discovery and its clinical application.

Animals↗
PubMed2006

The absence of lymphatics in normal and atherosclerotic coronary arteries in man: a morphologic study.

It has been suggested by various investigators that the impairment of lymphatic drainage from the coronary arteries may play a role in predisposition to coronary atherosclerosis, the pathogenesis of which is certainly multifactorial. In our study, no lymphatic vessels were found in the walls of the coronary arteries (adventitia, media and intima) in 51 human hearts from patients ranging in ages from 3 months to 83 years with normal coronary arteries, coronary atherosclerosis, and cardiomyopathy. Visualized lymphatics were located solely in the periadventitial area, and these lymphatics were more irregular in hearts from older persons. With injection, histology, and electronmicroscopy methods we could not detect penetration of lymphatics into the wall of coronary trunks in normal as well atherosclerotic arteries. In all coronary arteries studied, and particularly in the atherosclerotic lesions, blood vasa vasorum could be visualized. In the atherosclerotic areas, vasa vasorum (angiogenesis) could be seen penetrating into the media and intima. Many of the thin-walled vasa vasorum could easily be mistaken for lymphatics. The absence of lymphatics draining the epicardial coronary arteries may be a predisposing factor to coronary atherosclerosis.

Adolescent↗
PubMed2005

[The map of superficial lymphatic system of the breast and relation to the sentinel lymph node].

AIM: The aim of study was to topographically map the superficial lymphatic drainage of the breast and its relation to sentinel node. DESIGN: Anatomical study. SETTING: Department of Oncogynecology, Clinic of Obstetric and Gynecology of 1st Medical Faculty of Charles University and General Hospital, Prague. METHODS: The study was performed on 19 female cadavers. After slow intradermal administration of Patent Blau into the periareolar region, into the centers and into the borders of the individual quadrants of the breast, the lymphatics were visualized and a careful resection of these lymphatics and lymph nodes was performed. The lymphatics were drawn onto a schematic map of the breast on a transparent sheet and afterwards a summation of all schematic maps was performed. A map of the lymphatic vessels of the breast was based on this summation. RESULTS: After subcutaneous administration of patent blue were clearly visualized the subareolar plexus and draining sentinel node in the axilla, as well as one or two supplying lymphatics. Despite great variability in the lymphatic drainage of the breast, it was demonstrated that the natural dominant drainage for the outflow of lymph from the superficial areas of the breast are the axillary nodes. CONCLUSION: From the course of the lymphatic vessels it is evident that the breast cannot be divided into functionally separate segments. According to the lymphatic map of the breast, one can assume that in carcinoma of the breast it is the lymphatic drainage and not the localization of the tumor that plays a primary role in the development of metastases. One cannot ignore the existence of alternative drainage pathways of the breast, but their role in the beginning of dissemination of tumor cells in comparison with the axilla is negligible. Subdermal administration of Patent Blau is a reliable and effective method of visualizing lymphatic vessels and the draining lymph nodes of the breast. Due to the meandering course of lymphatics in the breast, we cannot understimate the role of radiation therapy after breast conserving surgery.

Aged↗
PubMed2005

Cutaneous and subcutaneous lymphatic drainage of the breast.

The aim of this study was to topographically map the superficial lymphatic drainage of the breast. The study was performed on 24 female cadavers. Patent blue dye was administered intradermally and subcutaneously. After visualization and dissection of the lymphatics, a schematic record of their routes was made on a transparency folio of the breast map. Afterwards, a summation was performed of all schematic records, and a map of the lymphatic vessels of the breast was derived. The natural dominant drainage for the outflow of lymph from the superficial areas of the breast is to the axillary nodes. This pathway plays a primary role in the initial stages of breast cancer. This observation does not exclude other pathways of lymph drainage, which probably play a secondary role except in cases where flow is limited in the primary lymphatic pathway. Although each quadrant is dominantly drained by one or two of its own collectors, it is also interconnected via the subareolar plexus with the other quadrants of the breast, and lymph collectors of the upper medial quadrant pass to the lower medial quadrant and vice versa. Lymphatic collectors from the medial quadrants followed the medial, cranial and caudal margins of the breast and afterwards ran into the axilla. The common interconnections of the individual quadrants of the breast with one or two collectors, which circumscribe the breast, but run outside the subareolar plexus, further increase the risk of developing locoregional recurrences. In some cases, the marginal lymphatic collectors of the breast may even run beyond the anatomical boundaries of the breast--particularly apparent in the submammary region.

Aged↗
PubMed2001

Morphology of lymphatics in human venous crural ulcers with lipodermatosclerosis.

A morphological evaluation of lymphatic vessels of skin leg ulcers was performed in 39 human subjects with longstanding venous insufficiency and lipodermatosclerosis. Light and electron microscopy demonstrated that the superficial fibrin and inflammatory cell layers and intermediate blood capillary layer of the ulcer bed, which were primarily granulation tissue, did not contain lymphatics. Moreover, lymphatic capillaries were present only sporadically in the transition zone from granulation tissue to the deeper collagenous scar layer of the ulcer. In some instances, in the deepest part of the ulcer bed near the crural fascia, there were one or two thicker lymphatic collectors with valves, which were continuations of collectors from the plantar foot region. Lymphatics were present at the border of the ulcer and in lipodermatosclerotic skin, but the endothelium and muscle lining layer were partially destroyed. Lymphatic capillaries were characterized by open interendothelial junctions in conjunction with subendothelial edema. In lipodermatosclerotic skin, the morphologic changes suggest that absorption of interstitial fluid and lymph is markedly disturbed adjacent to the ulcer bed, which likely contributes to both slow healing and high recurrence of skin ulcers associated with longstanding venous insufficiency.

Adult↗
PubMed1999

Failure of the canine principal ascending epicardial lymphatic to regenerate after transection.

We transected the principal ascending anterior epicardial cardiac lymphatic in 10 dogs, and after varying time intervals reoperated to look for lymphatic regeneration using dye injection. Photographs and sketches were made to record the findings, and in six dogs serial histologic sections were also examined. In none of the 10 dogs was regeneration of the transected principal cardiac lymphatic detected although small lymphatic collaterals from the distal side of the lymphatic developed in 2 dogs. Further studies are merited to assess the role of lymphatic insufficiency in the development of coronary vasculopathy and chronic rejection after cardiac transplantation and other heart operations (e.g., coronary artery bypass) that may injure lymphatic drainage capacity.

Animals↗
PubMed1999

The morphology of the lymphatics of the coronary arteries in the dog.

On the supposition that pericoronary lymphatics play an important role in the efflux of interstitial fluid from the blood vessel wall, we examined the morphology of pericoronary arterial lymphatics in the dog. After ligation of the principal epicardial drainage lymphatics, after ligation of the left anterior descending coronary artery, after induced pericoronary inflammation and after instillation of India Ink into the pericardial sac using light, dissecting, and electron microscopy. The findings were compared with non-operated (control) dogs. Lymphatic drainage of the coronary arteries is via adventitial lymphatics, which do not penetrate to the media and via periadventitial lymphatics consisting of a subepicardial lymphatic plexus overlying the coronary arteries. The smaller arterioles in the ventricular muscle have many more accompanying lymphatics than do epicardial coronary arteries. In the latter arteries, prelymphatic channels formed by collagen fibers in the media likely transport interstitial fluid to the adventitial and periadventitial lymphatics. Arterial contraction also likely plays a role in propulsion of coronary arterial interstitial fluid towards adventitial lymphatics.

Animals↗
PubMed1996

Visualization of the lymphatics of the heart and the mediastinal drainage pathways in the living cynomolgous (Macaca mulatta) monkey.

Our interest in the effects of impaired cardiac lymph drainage on coronary atherosclerosis led us to study the cardiac lymphatic anatomy in the monkey, generally considered the ideal experimental animal for examining coronary artery disorders. Short-term and long-term studies to visualize the cardiac lymphatic system and its mediastinal drainage pathways in 14 living monkeys confirmed that the epicardial collecting lymphatic anatomy is comparable to that of man, dog, and pig. These lymphatics, and particular lymphatic drainage to the cardiac lymph node in the right mediastinum, are difficult to visualize, in good part, because lymph uptake of such tracers as India Ink and T1824 blue dye is extremely slow. By modifying our techniques and taking cognizance of the slow lymphatic uptake of the tracers, we have been more successful in visualizing the mediastinal cardiac lymph node. Though our studies confirm that the lymphatic drainage of the monkey heart is similar to that in other mammals, we conclude that the "monkey model" has several drawbacks to study the effects of impaired cardiac lymph flow because of the laborious requirements to visualize successfully the cardiac lymph node. Perhaps the development of new markers would make this lymphatic system more approachable for experimental investigation.

Animals↗
PubMed1995

Are peripheral lymphatics damaged by high pressure manual massage?

Massage of the foot in men and the hindpaw in dogs was performed by applying external pressures of 70-100 mmHg for a period of one, three, five, and ten minutes with a frequency of 25 strokes per minute. This protocol was performed on individuals without edema, on dogs with experimental lymphedema and men with post-thrombotic venous edema. After ten minutes of forceful massage, focal damage of lymphatics was present. In a group of dogs with lymphedema and men with post-thrombotic venous edema, the alteration of lymphatics was greater than in normal individuals and evident only after 3 to 5 minutes of massage. At first, the forceful massage affected the endothelial lining of the initial lymphatics. Alterations of lymphatic collectors were visible later. The fluid in lymphedema was translocated by massage using high pressure from the interstitium into the lumen of lymphatics by means of the open junctions and by artificial cracks that develop from injury to the lymphatic wall. Vigorous massage in lymphedema also produces loosening of subcutaneous connective tissue, formation of large tissue channels and release of lipid droplets that enter the lymphatics. By this mechanism, massage helps reduce the amount of fat cells in the lymphedematous leg.

Adult↗
PubMed1995

The lymphatic drainage of the parietal pericardium in man.

Parietal pericardial lymphatics were visualized by indirect and direct India ink injections in 35 human cadavers. Studies included examination of cleared specimens under the dissecting microscope and standard light microscopy. The lymphatic vessels of the ventral pericardial surface most often pass along the phrenic nerves cranially to terminate in the anterior right and left and transverse mediastinal nodes, or caudally to the diaphragm or prepericardial lymph nodes. The lymphatics draining the lateral parts of pericardium pass to the anterior mediastinal, tracheobronchial, lateropericardial, prepericardial and posterior mediastinal (juxtaesophageal) lymph nodes. The posterior part of the pericardium drains to the juxtaesophageal and tracheobronchial nodes. Lymphatics from the diaphragmatic part of the pericardium pass to the right lateropericardial and prepericardial, juxtaesophageal and tracheobronchial nodes. The pericardial cupula is anteriorly drained to the anterior mediastinal nodes, and posteriorly to the tracheobronchial nodes. In cleared specimens two networks of lymphatic vessels are seen to surround the pericardial space. On the ventral surface, the lymphatics of the parietal pericardium connect to lymphatics in the pericardial fat and areolar tissue. On the lateral and posterior surfaces, the lymphatics of the parietal pericardium anastomose with lymphatics of the reflected mediastinal pleura. These anatomical observations offer new insights into the mechanisms of turnover of pericardial fluid and into the mechanisms of occurrence of chylopericardium.

Adolescent↗
PubMed1994

The lymphatics of the canine parietal pericardium.

A careful anatomical study of the lymphatic drainage from the parietal pericardium reveals a complicated network that is notably different from that defined by the instillation of markers into the pericardial sac. The pericardial cupola and the posterior (dorsal) area of the parietal pericardium drain directly to the cardiac lymph node in the right upper mediastinum by relatively short lymphatics. The lymphatics of the anterior and lateral areas of the parietal pericardium pass to collecting vessels that travel cranially or caudally along the phrenic nerves. The former traverse specific lymph nodes and then enter the right or left venous angles. The latter pass caudally and then drain to the major collecting systems from the area of the diaphragm.

Animals↗
PubMed1992

The efferent cardiac lymphatic pathways in the macaque monkey.

In ten postmortem hearts of the Macaque monkey (M. mulatta), the coronary lymphatics were visualized using an India ink suspension in 2% gelatin. The left coronary lymphatic initially passed to the dorsal surface of the aortic arch. In five hearts, this lymphatic went directly to the cardiac lymph node, whereas in the others, it first ascended to the left superior tracheobronchial node and then interconnected with the cardiac lymph node. The right coronary lymphatic usually passed in front of the ascending aorta and common arterial (brachiocephalic) trunk and entered the cardiac lymph node. In two hearts, however, the right coronary lymphatic first ascended to an anterior transverse mediastinal node and from here lymphatics joined the cardiac lymph node. Those lymphatics that passed cephalad from the cardiac lymph node to the right anterior mediastinal nodes and the right paratracheal nodes ultimately emptied into the right venous angle. Those lymphatics that passed cephalad from the cardiac lymph node to the anterior transverse mediastinal nodes ultimately emptied into the left venous angle. In five other Macaque monkeys (M. mulatta and M. fascicularis) after marker injection (T1824 blue dye and micropulverized barium sulfate) into the living heart or pericardium, lymphatic drainage beyond the base of the heart could not be demonstrated. Whereas postmortem morphologic studies suggest that the monkey coronary lymphatic system is amenable to obstruction by removal of the cardiac lymph node and interruption of its adjacent lymphatic connections, effective methods for visualizing the mediastinal lymphatic collecting system in the living monkey must be developed before experimental cardiac lymphatic ablation can be accomplished in this species.

Animals↗
PubMed1990

Morphology of the region of the coronary sinus in respect to coronary sinus rhythm.

The arterial supply to the region of the coronary sinus and the interatrial septum was examined in 18 normal canine hearts. In 13 of a further 18 dogs, coronary sinus rhythm was evoked by the ligation of atrial arteries, subsequent to which the arteries were visualized by injection of latex. A stable coronary sinus rhythm is evoked by producing ischaemia in an extensive area of the right atrium, including the sinus node, the interatrial septum and Bachmann's bundle, but preserving from ischaemia the posteroinferior part of the right atrium. Microscopical examination of the hearts with coronary sinus rhythm, and comparison with 9 control hearts, failed to demonstrate any morphological centre, in the form of nodal cells, which might have been responsible for the abnormal rhythm. In the posterior part of the right atrium, the ischaemic changes failed to affect the approaches of the atrioventricular node. The approaches were predominantly composed of cells poor in myofibrils mixed to a variable degree with cells of the working myocardium. We discuss the possibilities of the development of coronary sinus rhythm and "circus movement" with regard to the participation of the approaches to the atrioventricular node.

Animals↗
PubMed1990

Arterial supply of the region of the coronary sinus in man.

Patterns of arterial supply to the atria were studied with respect to the coronary sinus region in 60 human hearts obtained from patients with a negative cardiac history and in 2 hearts with ECG-demonstrated coronary sinus rhythm. The atria, including the interatrial septum, were supplied by the right (40%) or left (30%) or both (30%) sinuatrial arteries which, however, did not reach as far as the posterior margin of the oval fossa and the coronary sinus. The region of the coronary sinus with the Eustachian ridge received direct branches from the trunk of the right (41%) or left (11%) coronary artery or both (48%) in the adjacent part of the coronary sulcus. Possible development of the 'coronary sinus rhythm' on the basis of multifocal damage of the sinuatrial arteries is discussed.

Aged↗
PubMed1987

Light microscopy of sinoatrial node ischaemia.

Ischaemia of the sinoatrial node (SAN) region was produced in 57 dogs by obstructing the sinoatrial nodal artery by injecting it with various media. In the light microscope ischaemia of the nodal cells resulted in myocytolysis. The cells were oedematous, with a distinctly cleared cytoplasm and cytoplasmic vacuolization. Macrophages penetrated into the nodal cells. Myocytolysis resulted either in disintegration of the cell membrane and the nucleus or in atrophy of nodal cells. The damaged cells were gradually replaced with collagenous connective tissue. Ischaemic changes in the light microscope appeared between hours 3 to 24 after the onset of ischaemia and continued to develop for a period of 4 to 5 weeks showing a variable intensity in different areas of the SAN region. The process became virtually stabilized between months 1 to 7. The degree of ischaemia was most probably responsible for the fact that changes of various degree--myocytolysis, atrophy and fibrosis--were present simultaneously. The preservation of ganglion cells in ischaemic tissue is discussed.

Animals↗
PubMed1986

Lymph vessels of the transplanted kidney.

Lymph vessels were evaluated in 20 transplanted canine kidneys. Prior to the occurrence of morphological rejection changes, transplants with good blood flow rates show areas with dilated but, less frequently, also undilated lymph vessels. In transplants with the presence of a rejection infiltrate and a decrease of the blood flow rate of 21-50% the lymph vessels may be focally dilated or, in contrast, narrowed by the cells of the rejection infiltrate. Numerous vesicles and vacuoles can be seen within the cytoplasm of endothelial cells. Interendothelial junctions may be occasionally open, the walls of endothelial cells become attenuated, and disintegration of the cell membrane is followed by a focal destruction of the wall and the development of defects. Cells of the rejection infiltrate penetrate through the gaps in the wall of the lymph vessels. The possible mechanism of the disintegration is discussed in this paper.

Animals↗
PubMed1984

Topography of intrarenal lymphatics.

The intrarenal topography of lymph vessels injected with India ink was examined in 32 canine kidneys. In the upper portion of the renal cortex most lymphatics were associated with subcapsular veins and tubules. In the cortical midportion lymphatics were generally aligned with interlobular arteries and veins, glomeruli, and tubules. These lymphatics commonly encircled interlobular arteries and formed an interconnecting plexus adjacent to glomeruli. In the lower portion (i.e., corticomedullary zone), renal lymphatics passed between loops of Henle and collecting tubules.

Animals↗