Method for isolating single cardiac cells in the guinea pig using pronase. The role of calcium ions

A method for isolation of guinea-pig cardiomyocytes with pronase has been developed. The method has been assessed in hearts perfused with solutions containing pronase (1 U/ml) and 200 microM Ca2+. Eighty per cent of the cells released were rod-shaped and 1.2 mM Ca2+ tolerant. Enriched medium 199 was used for all solutions. Sodium and slow inward currents recorded from cells dispersed with pronase were similar to those recorded from cells isolated after prolonged exposure to collagenase. Two principal factors are to be marked: (a) presence of high enough amounts of Ca2+ in enzyme solution (up to 200 microM); (b) use of the enriched medium in all the stages of the procedure.     

Mechanism of circulatory disorders in animals irradiated at high doses

Some data are reported on pathoanatomical changes, a status of the microcirculatory channel and the coagulogram of animals affected by high doses of ionizing radiation. The signs of disseminated intravascular blood coagulation have been revealed. The authors discuss the relationship between clinical manifestations with coagulopathy development and circulatory disturbances during intestinal and cerebral forms of acute radiation sickness.     

The state of hyporeactivity in interferon production: localization and partial purification of the factor repressing the interferon production

The hyporeactivity factor in interferon production by L-929 cells designated IRP (interferon repressing protein) has been studied. In particular, its localization and methods of its purification have been studied. The kinetics of IRP accumulation by producing cells correlate with the development of hyporeactivity condition. Most of IRP is localized in cell sap and in ribosomal fraction in evidence to regulatory role of repressor at the level of interferon mRNA translation. A 100-fold increase in repressor activity was achieved by IRP concentration by ammonium sulfate precipitation. IRP as well as interferon have been shown to possess high affinity to polyU sepharose. The preparations of IRP and interferon concentrated by ammonium sulfate precipitation were subsequently purified by fractioning in a polyI sepharose column. A 10,000-fold (6 x 10(4) U/mg) purification was achieved for IRP and 250-fold (10(4) U/mg) for interferon.     

Electron microscopic study of the cytoskeleton of human podocytes

The ultrastructural study of man's cytoskeleton of podocytes is carried out. Populations of podocytes with two different types of structure of the cytoskeleton in dependence on age (2, 4, 6, 37 and 65 years) is revealed in kidneys. The first type of cytoskeleton of the podocyte is peculiar for children's age and is characterized by branched, high density microfilament network, expressed by system of microtubules and single myofilaments. The intermediate filaments here are either utterly absent or present so feebly they find themselves "disguised" by other strongly developed components of cytoskeleton and revealing them with the help of technique of electron microscope is impossible. In kidneys of adults, and especially of old aged persons podocytes with other type of organization of the cytoskeleton are mainly identified. The distinctive signs of the last are bundle arrangement of microfilaments, plural bundles of intermediate filaments and individual microtubules. This study permits to make a conclusion that during individual development and growing old in kidneys of high animals and man, probably, physiological changes causing morphological reconstruction of cytoskeleton which is accompanied by intensive development of intermediate filaments' system with simultaneous "involution" of microtubules and microfilaments' systems take place.     

Taxonomic spectrum of pathogens of mixed infections in oncology patients and principles of their antibacterial therapy

Mixed infections were observed in oncological patients irrespective of the tumor or infectious process localization. 25-30 per cent of the pathological materials from such patients were contaminated with bacterial associations. The number of the associates ranged from 2 to 5 depending on the pathological material tested. Therapy of infectious complications due to pathogen associations should stem from analysis of many factors, i.e. properties of the isolated or likely pathogens, individual characteristics of the patients, compatibility of the drugs used and their pharmacokinetic features.     

Individual and age-related features of the extrinsic arteries of the adrenal glands in newborn infants

The origin, form, dimensions and position of the main and accessory adrenal arteries have been investigated in 192 preparations of the adrenals obtained from corpses of newborns with body mass of 2,500-4,800 g. The adrenal vessels are injected with thicken and roentgenocontrast masses, that is followed with roentgenography, photography and preparation. The main adrenal arteries occur: superior--in 100% (from 2 to 19), middle--in 75% (from 1 to 4), inferior--in 66% (from 1 to 6). The accessory arteries are noted in 66%: inferior--in 44%, middle--in 15%, superior--in 6%. The number of the accessory arteries is from 1 to 6. The greatest variability in number demonstrate the main superior (Wn-1323) and the accessory inferior (Wn-900) arteries. There is not any essential difference in the total number of right-sided and left-sided arteries. There are two extreme forms of the organ's blood supply: the aortal (13%) and the renal (3%). A mixed form (84%) is observed more often when all the three groups of the adrenal arteries participate. The diameter of the main adrenal arteries varies: the superior--0.1-0.75, the middle--0.1-1.5, the inferior--0.1-1.5 mm. The summation diameter of all the adrenal arteries that approach the organ is 2.2-6.2 mm. Right-sided and left-sided differences are not significant.     

Phase separation in dipalmitoyl phosphatidylcholine bilayers induced by ionophores and binary electrolytes

Thermotropic behavior of unsonicated aqueous dispersion of dipalmitoyl phosphatidylcholine (DPPC) has been studied by scanning microcalorimetry and fluorescent probe method. Phase separation in the lipid bilayers was observed for systems containing ionophores (valinomycin, dinactin) and 1 : 1 electrolytes (NaCl, KCl, RbCl, CsCl). The ratio of lipid phases coexisting in the systems appeared to be dependent on the concentration of the electrolytes. Changes in the thermotropic properties of the lipid phase induced by valinomycin were observed when K+ and Rb+ ions-forming complexes with the ionophore were present in the systems. The latter phenomenon was not found for the systems containing dinactin possessing a lower ability for complex formation with the cations.