Genome instability and chromosomal rearrangements in a heterothallic wine yeast

Wine strains of Saccharomyces cerevisiae are usually homothallic diploids and show chromosome length polymorphism. We describe the analysis of a heterothallic strain heterozygous for the mating types a and alpha. Surveying cultures of the strain, we found a remarkable degree of heterogeneity in ploidy and in electrophoretic karyotype. The CHEF analysis of tetrads and dyads revealed an enormous variability of band patterns hampering the analysis of chromosome segregation. We propose that the instability of ploidy and chromosome polymorphism might be due to heterothallism that precludes the process "genome renewal" (MORTIMER et al. 1994) by selfdiploidization of spore clones.

The STR systems HumVWA and HumACTBP2 in a Hungarian population

Allele frequencies of the Short tandem repeat systems HumVWA and HumACTBP2 were determined from 105 unrelated individuals from the area of Szeged, Hungary. A total of 8 alleles was detected for VWA, and 23 alleles were found for ACTBP2. In both systems no deviations from Hardy-Weinberg equilibrium were observed. A comparison of the Hungarian and German frequency profiles revealed significant differences at both STR loci.

Toxicity of the herbicides Flubalex, Fusilade S and Maloran 50 WP to chicken embryos after administration as single compounds or in combination

The teratogenic effects of three herbicides (Flubalex, Fusilade S and Maloran 50 WP) were studied in chicken embryos. Each of the three test substances was administered on days 0 and 12 of incubation. Treatment was followed by evaluation on day 19. The compounds were injected into the air-chamber of eggs at three different concentrations. The medium concentration corresponded to that usually applied in chemical plant protection. In order to determine the combined toxicity of the three herbicides, the medium concentration of Maloran 50 WP and three different concentrations of Flubalex of Fusilade S each were administered simultaneously at a final volume of 0.1 ml per egg, at similar times. Evaluation was done on day 19. In tests of individual toxicity, after injection on day 0 of incubation Maloran 50 WP and Flubalex caused a significant reduction in body mass, while Maloran 50 WP and Fusilade S resulted in marked embryonic mortality. After injection on day 12, the medium and the highest concentration of Flubalex and the highest concentration of Fusilade S caused a marked increase in embryonic mortality. The developmental anomalies were of sporadic nature: their incidence increased only after Flubalex treatment, irrespective of the time of administration. The combined administration of Maloran 50 WP and Flubalex on day 0 resulted in a significant or marked body mass reduction in all groups. Embryonic mortality increased substantially after treatment with the highest dose of Flubalex, while all three concentrations of the other two herbicides led to similar results. When treatment was performed on day 12, the two highest concentrations of Flubalex and the highest concentration of Fusilade S caused expressed embryonic mortality. The developmental anomalies did not show a dose-dependent effect in any of the test series.

[Blood group characteristics of Hapsburgs belonging to the line of Josef, Palatine of Hungary]

Results of the reported examination of blood-group characteristics and inheritance of historical personalities of Hungary evidence that blood-group determination or identification can be successfully carried out from bone or/and hair specimens having been buried and/or conserved for a long time. It should be mentioned, that determination of blood-group in such specimens and evaluation of results requires an exceptional carefulness since specific reactions may occur.

Myocardial lesions in hemorrhagic hypotension

The myocardial alterations were investigated in dogs after hemorrhagic hypotension. Development of metabolic acidosis with increased lactate concentration was observed in all cases. Focal hemorrhages and hypoxic changes developed in the subendocarial region. Typical so-called zonal lesions were demonstrable in the mural myocardium of both ventricles. The hypoxia, increased level of catecholamines, metabolic disturbances, and probably cardiotoxic products may play a role in the pathomechanism. The alterations which are potentially reversible are transformed into irreversible damage only in most severe cases. The necrosis is of hypercontraction type, and is associated with rapid calcification and mononuclear cell infiltration. The morphologic changes may explain the circulatory disturbances of cardiac origin and may represent the basis of development of the low cardiac output syndrome in hemorrhagic shock.

Investigation of the short-time autolysis of rat hearts by means of SDS. Polyacrylamide gel electrophoresis and electron microscopy

The short-time autolysis of hearts was regarded as a model of ischaemic heart failure. Therefore, isolated rat hearts were subjected to 30--120 min autolysis in a Locke solution at 37 degrees C. Electron microscopic examinations and myofibrillar preparations were made from the autolysed heart ventricles. The myofibrillar proteins were resolved by SDS-polyacrylamide gel electrophoresis. After 30 min autolysis the amount of a protein of 192,000 daltons greatly increased. At the same time on the electron micrographs the focal destruction of filament destruction on the A filament area and the mitochondrial structure altered too. After 60 min autolysis another protein of 36,400 daltons appeared. On the electron micrographs the focal desintegration of Z membranes and the focal destruction of I filaments can be observed. After 120 min autolysis further proteolytic products could not be detected by gel electrophoresis but on the electron micrographs the destruction of Z membranes and I filaments became more pronounced.

[Myocardial damage in hemorrhagic hypotension]

Damage to the myocard caused by the loss of blood was studied in experiments on dogs. After long-lasting hypotonia focal lesions of the myocard of degenerative type have been found. Desorganization of the myofilaments and invagination of the disc could be seen in the area of the intercalar discs. Filaments in the other regions have not shown any alterations. In the mitochondria hypoxic lesions were revealed. One part of the alterations are not reversible. After 48 hours of survival focal necrosis with hyper contraction and calcification could be observed. It was surrounded by cellular infiltration containing mononuclear cells. Cellular necrosis revealed, may lie on the basis of the central lesion of the circulation appearing after long-lastng hypotonia.

[Myocardial lesions in acute increase of the intracranial pressure (author's transl)]

Myocardial lesions occuring in diseases with acute increase of intracranial pressure were investigated. Morphologic alterations in heart muscle in spite of different lengh of surviving and various causes of the death were of similar type. In every case subendocardial haemorrhage could be observed on the septal surface and on the papillary muscle of the left ventricle. Focal intracellular edema, myocytolysis were revealed in 76%, focal necrosis of hypercontractic type developed in 52% of the cases. Cellular infiltration occurred around the alternations observed in 3 cases. It is concluded, that damage to the heart muscle is not caused directly by the increased intracranial pressure or catecholamine mobilisation, but seems to be the consequence of the acute myocardial hypoxia.

The effect of isolated perfusion on limb circulation in peripheral arterial occlusion

The effects of isolated limb perfusion were studied in 12 patients suffering from peripheral arterial occlusion. The hemodynamic investigations show that the vascular resistance decreases considerably during isolated limb perfusion. After administration of a vasodilator cocktail, added to the perfusion, the vascular resistance continues to decrease. Angiographic records, made before, during and after the perfusion, suggest that the calibre of the collateral vessels increases significantly and besides new collaterals can also be observed. The mechanism of the effects of isolated hyperbaric limb perfusion and its clinical value are discussed.

[Morphological and toxicological studies of experimental diquat poisoning]

Lesions caused by a single subtoxic dosis of diquat were studied in rats. After the administration of diquat on the first day it was revealed in highest concentration in the lung, but in two weeks no traces of the drug could be demonstrated. On the first and third day activity of peroxidase in the liver and the number of peroxisomes as well significantly increases. On the first day after the administration of diquat in the lung damage to the surfactanct and increase of the capillary permeability was observed. Later degenerative changes of the pneumocytes I and II type, focal haemorrhagic edema and presence of alveolar macrophages can be revealed. In two and in four weeks a slight pulmonary fibrosis remains to show the damage to the lung. In kidney tubular lesions of toxic origin, in the phase of the regeneration increase of the number of lyosomes could be revealed. On the basis of this study and the data of other authors the possible mechanism of the intoxication with diquat is discussed.

[Anoxic myocardial lesions in man, developed during extracorporeal circulation, studied by electron microscopy]

Anoxemic changes of the myocardium were examined at 20 patients operated on in extracorporal circulation. At a mild degree hypothermia (30 degrees C) morphological changes appear after a 20 minutes period of anoxaemia. Damage to the myocard of irreversible character could be revealed after an anoxaemic period of 43--55 minutes. An intermitting perfusion of the coronary arteries delayes the formation of the lesions, although in cases of ligation of the aorta for 90 minutes severe mitochondrial changes and deformation of cells were seen. The best method for protecting the myocard is an isotherm perfusion of the coronary arteries. Clinical and laboratory findings show that necrosis of the myocard has a focal character and may play a part in formation of postoperative lesions.