Search PubMed⌕ Search

Biomedical subjects

Z Nagy

Publications and source records attributed to Z Nagy.

At least 199 records · Page 11Linked to original sources
PubMed1990

Local recurrences following colorectal operations.

In about 15-20% of patients operated for colorectal tumours local recurrences develop mainly in the first postoperative year. This large number can only be reduced by adequately radical operations taking into account the patient's age, tumour site and the tumour-biological factors. Indispensable factors are the organized care and regular control of the operated patients with an emphasis, beside CEA test on US and CT studies. In local recurrences attempt should be made at removal of the tumour by an additional operation which is implementable in 20-30% of cases. For palliative treatment first of all radiotherapy can be applied for pain relief.

Adenocarcinoma↗
PubMed1989

Valve surgery combined with myocardial revascularisation. Report of 62 cases.

Combined valvular and coronary bypass surgery was performed in 1984-1988 in 62 patients. Their age range at operation was 38-75 (mean 59) years and more than 90% were in NYHA class III or IV. Valve replacement was performed in 55 cases--mitral in 13, aortic in 33, tricuspid in one and combined valve procedures in eight cases--and valvular correction in seven cases. The patients also received a total of 92 coronary artery grafts (1-4/patient, mostly as single grafts). The hospital mortality was 3% and there were two late deaths. Follow-up was 100% complete 2-52 (mean 22) months after surgery, and more than 90% of the survivors were improved.

Adult↗
PubMed1988

Cerebral vessels cryofixed after hyperosmosis or cold injury in normothermic and hypothermic frogs.

Three purported means by which large solutes may penetrate the blood-brain barrier are: permeabilized tight junctions; vesicular transport; or channel formation across cerebral blood vessels. The role of vesicular transport has been questioned, in part, because many cytoplasmic vesicles are induced by aldehyde fixation. Cryofixation reduces this artefact and was used to see structural changes in frog cerebral endothelium made permeable to plasma solutes after perivascular exposure to hyperosmotic (3 M) urea, or injury with a cold probe (-50 degrees C). Some control and experimental frogs were made hypothermic so as to inhibit endocytosis and autolytic changes. The brains of some untreated controls were immerse-fixed in aldehydes. Other controls and all other brains of normothermic or hypothermic animals were rapidly frozen, then substituted with acetone-fixative. The interendothelial tight junctions separate partially or completely, after hyperosmotic exposure, in one third of the junctions. Blood-borne ferritin and Evans blue pass through some of the patent junctions. Junctional opening is caused by cell shrinkage, because the perimeter/area ratio of individual endothelial cells in the hyperosmotic group is significantly greater than in the control, due to a decreased area. Large 0.08-0.32-micron-wide invaginations or pits of the endothelial cell membrane characterize both cryofixed and aldehyde-fixed vessels. The pits often appear as isolated vesicles in the cytoplasm, but serial sections reveal that many communicate with either the capillary lumen or subendothelial space. No series of pits opened onto both lumen and space to form a transendothelial channel. The number of vesicles in aldehyde-fixed specimens is about 4 times greater (P less than 0.01) and in the cold injured, cryofixed brain capillary, about two times greater (P less than 0.01), than in the cryofixed control. Hyperosmotic exposure does not increase the number of pits. The permeabilization of anuran cerebral endothelium by hyperosmotic treatment or cold injury is thus by means of an intercellular rather than a transcellular route.

Animals↗
PubMed1988

Open mitral commissurotomy in pregnancy. A case report.

Correction of severe mitral stenosis by open commissurotomy during the second trimester of pregnancy is reported. The further course of the pregnancy was uneventful and at 34 weeks a healthy boy was vaginally delivered. Mother and child were in good health on discharge from hospital one month later.

Adult↗
PubMed1988

Combined surgical procedure for the prevention of blindness caused by progressive high myopia.

A combined prophylactic procedure consisting of the strengthening of the sclera by fascia lata implants and the laser photocoagulation of peripheral retinal degenerations has been developed for the prevention of blindness caused by progressive high myopia. More than 7 years of experience gained with over 400 patients showed that none of the treated eyes developed retinal detachment or other severe complications of high myopia. Moreover, the degree of myopia decreased by a mean value of 3.0 D in 90%, and the visual acuity improved by a mean value of 0.15 in 70% of the patients treated. The authors suggest that their combined prophylactic procedure should be tried out and introduced to general ophthalmological practice.

Adult↗
PubMed1987

Conditions of formation of the heparin-fibronectin-collagen complex and the effect of plasmin.

The formation and composition of the insoluble heparin-fibronectin-collagen complex and its degradation by proteolysis was investigated. At fixed concentrations of the other molecular components of the complex, the maximal rate of complex formation, measured turbidimetrically, was reached at a concentration of 4 microM heparin and 0.9 microM collagen, while the rate of complex formation was linearly related to concentrations of fibronectin as high as 3 microM. Heparin was incorporated into the complex in a saturable manner, and was released in active anticoagulant form by plasmin but not by urokinase. The complex formation was inhibited by 5 mM calcium or 250 mM NaCl as well as by polybrene or spermin. It is suggested that fibronectin binds both heparin and collagen cooperatively to form an insoluble ternary complex of the extracellular matrix.

Binding, Competitive↗
PubMed1987

Surgery of calculous hydrocalyx (calyceoplastic surgery).

A modified surgical technique for calculous hydrocalyx, based on partial calyceal resection with simultaneous correction of the morphological abnormality responsible for stone formation is described. Access to the calyx is gained by a modified marginopolar resection. The modification developed by the authors consists in carrying the resection line laterally to the vertical axis of the kidney. The parenchyma is closed by U-shaped "hair-pin" stitches. Preparation of the limbic, pelvic and ureteral areas is abstained from, thus avoiding scarring which might affect renal lymph and blood flow and interfere with urinary transport. The results obtained in 85 cases of calculous hydrocalyx over an 8-year period were satisfactory. The rate of calculous recurrences was not higher than 3.5 per cent.

Humans↗
PubMed1987

Tight junctions of brain endothelium in vitro are enhanced by astroglia.

The belts of endothelial tight junctions, which impede diffusion between blood and brain, were reduced to fragmentary, small junctions in subcultured brain endothelium. When cocultured with the capillaries' nearest neighbor, the astrocytes, these endothelial tight junctions were enhanced in length, width, and complexity, as seen by en face views of the cell membranes with freeze-fracture electron microscopy. Gap junctions, common in brain endothelium in vitro but absent in mature brain capillaries in vivo, were markedly diminished in area from among the enhanced tight junctions of the cocultures. Thus, astrocytes in vitro play a role in the formation, extent, and configuration of the junctional complexes in brain endothelium, whose diffusion barrier may likewise be influenced by astrocytes in vivo.

Animals↗
PubMed1986

Interaction of casein with human polymorphonuclear cells.

Attachment of 125I-casein to PMN cells was investigated. Iodination did not decrease the chemotactic effect of casein. 125I-casein binding was increasing toward a maximum reached at about 45 min at 24, and 37 degrees C. At 4 degrees C the binding was proportional to time for 45 min. No saturation was achieved even at 15 mg/ml casein. About 40% of casein remained attached to PMN in a casein-free medium after 60 min, at 37 degrees C. Pretreatment of the cells with trypsin or butanol, or the presence of indomethacin, azide, and PMSF did not affect the binding of casein. The hydrophobic amino acid, leucin counteracted the attachment of casein. Our data show that at chemotactic doses casein is bound specifically to cell membranes by hydrophobic forces. The induction of chemotaxis may be due to micellar casein-membrane lipid complexes.

Adult↗