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Biomedical subjects

Z Glinka

Publications and source records attributed to Z Glinka.

17 recordsLinked to original sources
PubMed1994

Ultrastructure of peripheral blood lymphocytes in some degenerative central nervous system disease.

The ultrastructure of peripheral blood lymphocytes of 30 children with degenerative central nervous system diseases was analyzed. The affected children were divided into four groups. Lysosomal storage were characterized by the storage of membrane-bound inclusions in peripheral lymphocytes. Ceroidlipofuscinosis was manifested by the presence of curvilinear bodies. The appearance of abnormal mitochondria was found in mitochondrial encephalopathies. The tubuloreticular structures seen in lymphocytes of some unclassified cases suggested viral factors that acted in prenatal life. All findings confirm the role of peripheral lymphocytes analysis in the diagnosis of degenerative central nervous system diseases.

Adolescent↗
PubMed1992

Inclusion body myositis (IBM). Morphological study.

Among the chronic idiopathic inflammatory myopathies inclusion body myositis (IBM) has emerged as a clinicopathologic variant. Slowly progressive weakness of the distal and the proximal muscle groups, the presence of rimmed vacuoles with basophilic granules as well as 15-18-nm filamentous inclusions in affected muscle confirm the clinical and histopathological distinction between inclusion body myositis and chronic polymyositis.

Diagnosis, Differential↗
PubMed1991

Type III collagen deficient EDS IV producing muscular hypotonia with abnormal muscle fibroblasts.

Muscle biopsy and fibroblast culture of a floppy child with Ehlers-Danlos syndrome type IV were studied. Biochemical analysis of the tissue showed drastically reduced amount of collagen type III. Electron microscopic examination of muscle as well as of cultured fibroblasts showed grossly dilated and dominated the cytoplasm endoplasmic reticulum. Dilatation may result from storage of an abnormal collagen type III molecule. Our observations indicate that type III collagen deficiency may be present clinically as a congenital muscle hypotonia. Specific ultrastructural abnormalities of fibroblasts found in muscle biopsy can enable the proper diagnosis.

Child↗
PubMed1991

Muscle cell death. Ultrastructural differences between muscle cell necrosis and apoptosis.

The morphology and incidence of muscle cell necrosis and apoptosis are presented. Necrosis which occurs as a massive tissue damage is structurally characterized by swelling of the muscle cell and disruption of cellular components. Apoptosis, on the other hand, is a process of active cellular self-destruction. It shows characteristic sequence of muscle cell shrinkage, which is ending in transformation of each muscle cell into compact apoptotic bodies that in turn are phagocytized by adjacent cells or macrophages.

Autophagy↗
PubMed1987

A Kinetic Analysis of Phytochrome Controlled Mesocotyl Growth in Zea mays Seedlings.

Mesocotyl elongation in 4 day old etiolated seedlings immediately following 3 hours of white light (3 h W) is reversibly controlled by phytochrome. Time-lapse video measurements were made of the 5 millimeter zone just below the coleoptile which is the main growth region of the mesocotyl. The growth kinetics were determined for five contiguous 1 millimeter zones subtending the coleoptile node for nonirradiated seedlings, for seedlings given 3 h W, and 3 h W followed by terminal far-red (FR) or red subsequent to the far-red (FR/R) irradiation. Each zone in nonirradiated seedlings exhibits exponential elongation kinetics during the early stages of elongation. This finding suggests that during elongation, a growth limiting factor is also exponentially increasing. Following 3 h W differences in the kinetic responses were found for each zone. In all zones, the inhibitory effect following the 3 h W is totally FR reversible. The effect of FR is reversed by R. The upper zone exhibits the fastest response and is the most plastic in its growth response. The three upper zones all exhibit spontaneous and sharp recoveries with time. It is suggested that the control by phytochrome is not inductive but rather continuous, the controlling factor being either the level of the far red-absorbing form of phytochrome (Pfr) or the ratio Pfr to total phytochrome.

Journal Article↗
PubMed1980

Abscisic Acid promotes both volume flow and ion release to the xylem in sunflower roots.

The effect of abscisic acid (ABA) on the exudation process in excised sunflower root was investigated. A promotion of both ion flux and volume exudation rate was observed. Cutting off the external supply of ions to the roots markedly increased the magnitude of the ABA effect. The promotive effect of ABA on exudation rate was extremely rapid (less than 6 minutes) and seemed to be biphasic. Reasons are given for relating the ABA effect to two separate actions, namely: (a) on water permeability; and (b) on the release of ions both from vacuoles to the cytoplasm and from symplasm to the xylem. Kinetin inhibited movement of ions to the xylem and its effect did not appear to be related to that of the ABA.

Journal Article↗
PubMed1977

Effects of Abscisic Acid and of Hydrostatic Pressure Gradient on Water Movement through Excised Sunflower Roots.

The effect of abscisic acid on the exudation rate from decapitated roots of sunflower plants (Helianthus annuus L.) was investigated in the presence and absence of an imposed hydrostatic pressure gradient. The magnitude of the abscisic acid effect was constant even when suctions up to 60 cm Hg were applied to the cut stumps.When roots were bathed in a THO-labeled nutrient solution, the course of the appearance of radioactivity in the exudate, expressed as a function of exudate volume, was not affected by abscisic acid treatment but was strongly speeded up by applying suction.The implications of those findings with regard to the water pathway through the root and the location of the abscisic acid effect are discussed.

Journal Article↗
PubMed1974

Fluxes of a nonelectrolyte and compartmentation in cells of carrot root tissue.

Permeation of thiourea into cells of carrot (Daucus carota L.) storage root discs was found to be governed by its concentration gradient only. The analysis of the course of thiourea efflux from preloaded discs shows two distinct exponential curves, apart from an initial very fast component. Reasons are given for relating the first exponential part of the curve to efflux from the cytoplasm and the second exponential part to efflux from the vacuole.The rate constant for thiourea efflux through the tonoplast is markedly temperature-dependent (activation energy 13.2 kcal mole(-)) and is lowered by 2,4-dinitrophenol and by phenyl mercuric acetate treatments. The rate constant for its efflux through the plasmalemma, on the other hand, has a low activation energy (4.2 kcal mole(-)), which is equal to that of free diffusion of thiourea in aqueous solution, and is not affected by the metabolic inhibitors. Possible reasons for the difference in the properties of the two membranes are discussed.

Journal Article↗
PubMed1972

Induced changes in permeability of plant cell membranes to water.

The half-time for THO equilibration was three times longer for a living carrot (Daucus carota L.) cylinder than for a dead one. Furthermore, the energy of activation of THO flux was more than twice as high for the living cylinder. Passage through living membranes thus constitutes a rate-limiting step for THO flux in carrot tissue.CO(2) increased the half-time (t((1/2))) for THO equilibration. Treatment with abscisic acid or with tertiary butanol decreased t((1/2)). In neither case was the selective permeability of the membrane destroyed.p-Chloromercuribenzoate and carbonyl cyanide m-chlorophenylhydrazone, if supplied together with abscisic acid or tertiary butanol, abolished their action. If abscisic acid or butanol was first allowed to act alone, its effect was stable to subsequent treatment with the inhibitors. p-Chloromercuribenzoate and carbonyl cyanide m-chlorophenylhydrazone at concentrations at which they affected abscisic acid and butanol action, did not influence THO flux in control tissue. At considerably higher concentrations, however, 2, 4-dinitrophenol and carbonyl cyanide m-chlorophenylhydrazone raised t((1/2)). The CO(2) effect was very rapidly reversible. Full reversal of the butanol effect required 3 hours, and that of abscisic acid required 4 days.

Journal Article↗
PubMed1966

Reduction in Turgor Pressure as a Result of Extremely Brief Exposure to CO(2).

CO(2) depresses water influx into sunflower hypocotyl segments of low water potential; by contrast, it stimulates flux into segments of high water potential. When segments of high potential were placed in a series of mannitol concentrations and allowed to achieve steady rates of water uptake, influx into CO(2)-treated tissue in a solution of 3 atm equalled that into control tissue in water. Reasons are given for deducing that a change in internal osmotic concentration (pi(i)) of the order of 40% would be necessary to account for this result on the basis of pi(i). Direct measurements (by cryoscopy and by the minimum volume method) detected no difference in the steady state value for pi(i) as between CO(2)-treated and control tissue. It was therefore concluded that CO(2) had caused some reduction in turgor pressure.Water uptake into tissue treated with CO(2) for only the first 2 minutes of a 30-minute period was equal to that into tissue treated continuously with CO(2), i.e. 3 times the control value. Ten seconds' CO(2) treatment produced a significant stimulation. When the cycles of treatment were repeated the samples receiving flashes of CO(2) maintained a rate of water uptake superior to that of the control, whereas influx into continuously treated tissue fell below the control value after 1 hour.CO(2) treatment applied in a moist air chamber stimulated subsequent water influx when the tissue was transferred to water. Fifteen seconds' treatment was sufficient to produce a marked effect. Even when a transition period of 30 minutes in the moist chamber was interposed between CO(2) treatment (5 minutes) and transfer to water, a stimulation was observed. The CO(2) effect could be achieved at zero degrees; 5 minutes' treatment in the moist chamber at zero degrees, followed by a 15-minute transition period at the same temperature, substantially increased subsequent water uptake at 25 degrees .

Journal Article↗
PubMedDate not supplied

An ultrastructural study of the vascular and muscular basement membrane in Duchenne-type dystrophy.

The ultrastructural distribution of basement membrane around the capillaries as well as muscle cells of boys with Duchenne-type muscular dystrophy was determined. In dystrophic muscles, a diffuse thickness of vascular as well as muscular basement membrane was observed. Lamina densa lost its regular ribbon-like appearance and was split into several thin layers. After staining with tannic acid (TA), a densely stained meshwork was present on the muscle cell surface as well as in the extra-cellular space. Hyaluronidase treatment removed TA-stained deposits, indicating that hyaluronic acid is a major component. Enzyme resistant structures, presumably fibrous long-spacing collagen fibrils, have been found in dystrophic muscles. Based on the results of the study, faulty structure of the basement membrane in dystrophic muscle is suggested.

Adolescent↗
PubMedDate not supplied

Ultrastructural study of motoneurons in Werdnig-Hoffmann disease.

Ultrastructural studies of the lumbar spinal cord in three children with Werdnig-Hoffmann (W-H) disease type Ia revealed numerous small neurons which appeared both atrophic and immature. We compared these motoneurons with anterior horn cells of a 3-month-old child, a 27-week and a 16-week human fetus, and found (1) that the motoneurons were much smaller in W-H disease, and (2) the Nissl substance was peripherally located and less developed. Signs of motoneuron immaturity as well as secondary degenerative changes suggest that in W-H disease neurons die either because they fail to make adequate peripheral contact or because the neurons are genetically intrinsically defective.

Anterior Horn Cells↗