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K Sames

Publications and source records attributed to K Sames.

34 records · Page 2Linked to original sources
PubMed1977

[Degenerative changes in the central region of aging human rib cartilage, as influenced by growing cross section diameter (author's transl)].

In the centre of aged human rib cartilage, a yellowing degenerative zone is seen, while in a circular peripheral region the tissue remains unchanged. The cartilage of the 12th rib shows decrease in diameter towards its free end. It therefore was used as a model to find out wether there is a critical diameter of the diffusion stretch leading to a degeneration of the centre. This stretch was to be compared with the diameter of the peripheral circular zone. Cartilage of the second rib was used for comparison. The length of the free end showing no degeneration was 2,5- to 4 mm. Its radius was longer than the diameter of the circular zone in the middle part of the 12th rib cartilage, but this was not found in the second rib cartilage nor at the base of the 12th rib cartilage. The difference between the cartilage of differing individuals was more striking than the difference found between all cross sections of the second and 12th rib cartilage. The length of the diffusion stretch is thought to be an accessorial cause of aging besides the age changes of the cells and intercellular matrix, but not the only cause.

Aging↗
PubMed1975

[Clinical, electron-microscopic, and histochemical investigations of conjunctivitis lignosa (author's transl)].

A case is briefly described in which a typical conjunctivitis lignosa appeared after the eye had suffered lime burns. In order to help clarify the morphological connection between mucopolysaccharide production and fiber development in the tumor tissue which occurred after the burn, samples were examined histologically, histochemically and with the use of the electron microscope. The tumor had a cartilage like consistency. Its structure could be devided into three regions. Region A is the pseudo-membrane. It has root like extensions which anchor it to the underlying tissue, and which morphologically appear partially homogeneous and partially fibrous. Blood cells and cell remnants are included in the tissue of the pseudomembrane. The histochemical examination of the pseudomembrane did not present a uniform picture. Along with small amounts of dermatan-sulfate and chondroitin-sulfate B the membrane probably contained a rather large amount of hyaluronic acid. The pseudomembrane borders on a granular tissue (Region B) which is distinguished by the wide metachromatic sheathes of the blood vessels found in it and the particularly large number of active fibroblasts along its edges. The silver impregnation method and the electron-microscopic examination showed that the vascular sheathes consist of bundles of reticular fibers which constitute a three-dimensional network. A similar sort of sheath was observed around the fibroblasts. Chondroitin-sulfate makes up the largest fraction of the mucopoly-saccharides near the fibers and appears particularly concentrated at the intersections of the fibers, although it is also diffusely distributed as well. Dermatan-sulfate (or heparan-sulfate) is found only in the mucopolysaccharide sheath of the fibers themselves. The deep region of the tumor (Region C) consists almost exclusively of blood vessels, their sprouts and the fibroblasts which, with their wide fibrous sheathes, almost fill the spaces between the blood vessels. The reticular fibers and their mucopolysaccharide sheathes have the same structure as that observed in Region B, The fact that the mucopolysaccharides did not appear in plaques but rather as bound primarily to the fibers is grounds for suggesting that a fiber development disorder, probably stemming from the pericytes and fibroblasts rich in ergastoplasm and fibrilles, could play the principle role in conjunctivitis lignosa. The cartilagen like consistency of the tumor could be a result of the arrangement of the fibers and their mucopolysaccharide sheathes. Brief remarks are included concerning the therapeutic consequences of the study.

Adult↗
PubMedDate not supplied

Histochemical studies on the distribution of acidic glycosaminoglycans in human rib cartilage during the aging process.

In human cadavers of different age five zones of basic substances can be distinguished around the cartilage cell by using hyaluronidase digestion and Alcian blue stain combined with various MgC12-concentrations. This treatment produces different reactions in the various zones. The zones are numbered according to their distance from the cell; thus zone 1 (Z1 = pericellular zone) is the nearest to the cell. Z 1 and Z 2 (inner territorial zone) contain hyaluronidase-digestible substance but Z 1 stains at higher electrolyte concentrations than does Z 2. The third zone (Z 3 = outer territorial zone) which first appears in childhood always contains hyaluronidase-resistant material and, besides, hyaluronidase-digestible material in adolescence. Since the distance between the cells increases with the proceeding process of aging, Z 4 (periterritorial zone) and Z 5 (interterritorial zone) appear in the cartilage centre. In adolescence only Z 5 can be found; it is slightly hyaluronidase-sensitive and stains even at high MgC12-concentrations. In adult and old cartilage a weakly basophilic zone 4 appears. The comparison of fixed and unfixed tissues renders the distinction between the zones feasible as the hyalurinodase resistance is increased in fixed tissue and, on the other hand, the structures appear less outlined in unfixed tissue. As far as the distribution of acidic glycosaminoglycans (GAG) is concerned the territories and interterritories are not clearly defined units, for part of the zones mentioned above can be arranged circumcellularly or, in addition, interstitially depending on the various cartilage regions and on the different periods of life. We assume that the pericellular as well as the inner and outer territorial zones belong to the cell itself and that their step by step appearance is due to a process of development whereas the periterritorial and interterritorial zones result from cell degeneration caused by aging, and expand, mainly, without cellular control.

Adolescent↗
PubMedDate not supplied

Age-related histochemical staining patterns of glycosaminoglycans in cell nuclei of different regions of the rat brain: a pilot study.

The brains of 6 rats aged 12 months (adult) and 6 rats aged 24 months (aged) were embedded in paraffin following steady state perfusion with fixation solution. Glycosaminoglycans (GAGs) were demonstrated by histochemical methods using the Alcian blue CEC method in combination with the Feulgen reaction and testis hyaluronidase. Cell nuclei revealed different patterns of GAGs in different layers of the brain cortex and in different cell types. In neuronal cell nuclei of layer 2, no GAGs are found and this may be the case also in certain types of pyramidal cells. There was a reduction of the blue staining components of the chromatin network by hyaluronidase, and also a reduction of the electronmicroscopic contrast by this enzyme in pilot study using a specimen of one animal. The enzyme effects were found to be more marked or even exclusively present in the group of aged animals. Thus, the contents of chrondroitin sulfates or hyluronate which are substrates of the enzyme may be increased either relatively or absolutely in cell nuclei of aged brains whereas GAGs resistant to the enzyme may be reduced in activity. Since GAGs are known to influence DNA activity, the variations demonstrated may be assumed to be of significance for the aging process in postmitotic cells.

Journal Article↗
PubMedDate not supplied

Changes of the glycosaminoglycan metabolism in human lung fibroblasts and porcine aortic endothelium cells influenced by the number of subcultures in vitro and by lipids in the medium.

In vitro aging fibroblasts and porcine aortic endothelium cells were treated with a commercial soy-bean lipid emulsion and incubated in 35S-sulfate or 3H-glucosamine respectively. The glycosaminoglycans (GAGs) were characterized by enzyme digestion following proteolysis. Uronic acid concentrations were determined in fibroblast cultures. The GAG content is lower in the last possible passage than in the foregoing ones. Lipid treatment leads to an increase, especially in early passages. The incorporation of radiolabeled precursors decreases with increasing in vitro age in both cell types. By lipid treatment the heparansulfate (HS) radioactivity of fibroblasts is increased insignificantly, while the GAG radioactivity of endothelium cells and the chondroitinsulfate (CS) radioactivity of fibroblasts are decreased. The in vitro age-related reduction of the precursor incorporation is more pronounced in CS as compared to HS, whereby the HS radioactivity shows a percentual increase, especially following lipid treatment. The effect of lipids shows changes related to in vitro aging. The role of cellular GAG metabolism and lipid loads in arteriosclerosis is discussed. Even in the arterial wall different cell types may react differentially.

Animals↗
PubMedDate not supplied

[Age-related changes in glycosaminoglycans in the cell nuclei of the rat liver--biochemical and histochemical pilot studies].

Cell nuclei of the livers of 12 male Wistar rats aged 24 months, and 16 male Wistar rats aged 4 months were isolated. 0.4 microCi [3H]-glucosamine/kg body weight were administered intraperitoneally. The livers of four animals were used for each biochemical analysis. The tissue was degraded by proteolysis, the glycosaminoglycans (GAGs) were isolated and the GAG types were determined by enzyme digestion, nitrite degradation and radiometry. The amount of GAGs was photometrically determined in single samples of pooled material of each of the two age groups. In paraffin sections (from other male Wistar rats of a different age), the influence of enzymes on specific GAG staining was observed. Most of the radioactivity was found in heparan sulfate (HS) and a lower content in chondroitin sulfates (CSs). In HS the incorporation increased with increasing age. The amount of HS showed no age-related differences. The results indicate an age-related activation of the HS metabolism. The GAG pattern and the age-related changes of the GAG types in total tissue (earlier results) are different from those in the nuclei. By histochemical methods, we observed a small but distinct effect of heparitinase in the cell nuclei.

Aging↗
PubMedDate not supplied

[Age-related changes in cellular activity in organ and tissue cultures of the human cornea].

Human autopsy eyes and material of eyes enucleated by various causes were used to prepare explants of the whole chamber angle and isolated stroma corneae for organ and tissue cultures. The age-related changes in chamber angle explants are obscured by interactions of the different cell types. In 75 human stroma explants aged from 5 weeks to 93 years the latent period for cell activation (i.e. the time needed for the activation of cells revealed by histological methods) shows its lowest values in cases under 20 years of age. The latent period for outgrowth of cells is not significantly related to age. The long-term reorganization of the tissue structure in the explants is disturbed in higher age.

Adolescent↗
PubMedDate not supplied

[Age dependence of the early reaction in glycosaminoglycan metabolism of the rat liver on damage following a single dose of thioacetamide].

Wistar rats aged 7 or 22 months resp. were treated with 50 mg/kg of thioacetamide (TAA) i.p. The TAA-treated animals as well as control groups of the same ages and containing the same number of animals were injected i.p. with 3H-glucosamine (0.2 microCi/g body weight) 2 hours before sacrifice. Previously to sacrifice, the livers had been perfused in narcosis with NaCl (0.9%). Following degradation of the tissue by pronase, specimen of the substances precipitable by ethanol were digested with chondroitinases, streptomyces-hyaluronidase, keratanase, and nitrite. The quantities of substances were estimated photometrically using Alcian blue; radiometry was performed following precipitation with cetylpyridiniumchloride. In aging animals the amount of dermatan-sulphate (DS) and of the total acidic glycosaminoglycans (a.GAG) is increased as compared to the younger animals, although there ist no age related difference in the incorporation of glucosamine. The incorporation per microgram a.GAG (spec. act.) is decreased. Following TAA the amount of DS is increased in both age groups, whereas the total amount of GAG is increased only in the younger animals. The incorporation per mg dry weight is also increased in all GAG types of both age groups which is also the case with the spec. act. (with the exception of HS in the younger animals). The increase of the incorporation per mg dry weight in DS is significantly lower in the older TAA-animals as compared to the younger ones. HS shows the same tendency, but there is no significance. The age related increase of hydroxyproline parallels that of DS.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetamides↗