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[Effect of iodine deficiency on the growth and formation of the bone tissue].

The authors studied several groups of children in terms of the height in endemic goiter regions and in the regions with no goiter incidence. Subject to study were also processes of osteogenesis and phosphocalcium metabolism in animals with iodine deficiency in the diet. It was established that in goiter endemic regions, the number of children under medium and of low height was increased while that of medium and over medium height, and the number of tall children were reduced. It was also found that iodine deficiency in the diet of animals entailed abnormalities in the growth patterns, destructive alterations in the bones and bone marrow, a decrease in the content of hydroxyproline, hexosamines, and in the activity of phosphomonoesterase-I in animal bones, as well as disorders of phosphocalcium metabolism.

Animals↗

Effect of lysosomotropic amine, chloroquine, on the radioactive incorporation pattern of glycosaminoglycans in human skin fibroblasts.

Control and chloroquine treated fibroblast cultures were incubated with 14C-glucosamine. The cells were separated from the medium and the pericellular matrix. The S-carboxymethylproteins in the medium were hydrolysed with trypsin and pronase. The glycosaminoglycans were treated with hyaluronidase, chondroitin AB-lyase and chondroitin ABC-lyase. The macromolecular 14C label per cell in the medium was higher in the chloroquine treated cultures than in the controls. The incorporation of the 14C-hexosamines per cell into the pericellular and intracellular compartment was not modified. The increased 14C-label in the medium of fibroblast exposed to chloroquine accounted for the increased incorporation of the 14C precursor into chondroitin 4 and 6 sulfates and dermatan sulfate.

Cells, Cultured↗

New bone formation and parathyroid activity effected by 1 alpha-hydroxyvitamin D3.

Adult male rats reared on a standard diet were treated with peroral dosages of 1 alpha-hydroxyvitamin D3 (1 alpha-OHD3). A rapid effect on the serum calcium level was found; the elevation (compared to untreated controls) occurred as early as two weeks and remained elevated throughout the treatment period. Histomorphometric analysis revealed a decreased resorption rate and increased incorporation of tetracycline after four weeks of 1 alpha-OHD3 treatment. These results were associated with a significant increase of cortical as well as trabecular bone, as well as increased levels of bone hydroxyproline and hexosamines. A clearly significant decrease in the total volume of parathyroids was found after six weeks; this was accompanied by a slight pycnosis of the chief cells, which may account for reduced parathyroid activity.

Animals↗

[Complex study of glycoproteins in liver disease].

The glycoproteins (GP) of 329 patients with liver diseases and 60 clinically healthy subjects were complexly studied: sialic acid, orozomucoid, haptoglobin, ceruloplasmin, cholinesterase, hexosamine and fucose. Modern laparoscopic, bioscopic, histochemical and histomorphological methods were used in making the diagnosis and determination of the disease phase; The liver diseases are characterized by quantitative and qualitative differences in the character of the GP changes in serum. GP are mostly changed in acute viral hepatitis, cirrhosis, extrahepatic cholestasis and liver tumours, less in chronic aggressive hepatitis and no change in chronic persistent hepatitis and steatosis. The complex GP study is of significance in the characteristic of the activity of the pathological process, in the specification of the liver function as well as for the prognosis of a certain disease.

Ceruloplasmin↗

Biochemical changes in the collagen of the palmar fascia in patients with Dupuytren's disease.

The palmar fascial tissues of more than 400 patients with Dupuytren's disease were studied biochemically and compared with normal tissue obtained from more than 100 patients who were undergoing hand surgery for other reasons. No alterations of the molecular structure or the state of macromolecular aggregation of the collagen in Dupuytren's disease were detected by wide or low-angle x-ray diffraction studies or by transmission electron microscopy. Major biochemical changes in the palmar fascia affected by Dupuytren's disease included increased collagen and hexosamine contents and the presence of galactosamine in the most severely involved tissue. Type-III collagen, which is virtually absent from normal adult palmar fascia, was abundant in the tissue of patients with Dupuytren's disease. Post-translational modifications included a very elevated hydroxylysine content, an increase in the total number of reducible cross-links, and the appearance of hydroxylysinohydroxynorleucine (virtually absent from normal palmar fascia) as the major reducible cross-link. Even palmar fascia from patients with Dupuytren's disease that appeared grossly and histologically normal showed the same biochemical changes, albeit to a lesser extent. All of these biochemical changes are similar to those that occur during the active stages of connective-tissue wound repair. This includes the rapid synthesis and turnover of collagen which leads to newly synthesized, immature collagen being more abundant in the involved tissue than in normal tissue. There is no evidence that the gross, macroscopic contracture of the palmar fascia in Dupuytren's disease is due to shortening, plication, or contraction of the collagen fibrils or fibers present in the tissue at the onset of the disease or synthesized during its development. Instead, we propose that the gross contracture (shortening) of the palmar fascia in Dupuytren's disease is due to an active cellular process that progressively draws the distal extremities of the affected tissue closer together at the same time that the original tissue is being replaced. The result of these two processes is simply a shorter, smaller piece of tissue fabric containing collagen molecules, fibrils, and fibers of normal length and organization, but with pretranslational and posttranslational modifications similar to those observed in collagens during the active stages of connective-tissue repair in general.

Adult↗

[Components of the prothrombin molecule during development of avitaminosis K].

Components of the blood plasma prothrombin molecule were studied in the course of alimentary K avitaminosis development in pigeons and rats. A gradual decrease in the content of hexosamines in the prothrombin molecule was observed when vitamin K was excluded from the animals' diet. This decrease may be associated with inhibition of glucosamine biosynthesis.

Animals↗

[Comparative study of six methods for lymphocyte isolation from several mammalian sources and determination of their carbohydrate composition (author's transl)].

The present paper deals with a comparative study on six methods for isolation of peripheral blood lymphocytes from various mammalian sources: Bos taurus L. (adult cow), Equus caballus L. (adult horse), Equus asinus L. (adult and young donkeys) and Sus scropha L. (adult pig). The following systems were used: a) Filtration through sand columns (a modification of Blaszczyszyn's method); b) Sodium metrizoate and "Ficoll 400" c) "Lymphoprep"; d) "Urovison" and dextran T150 (a modification of GILI et al.'s method); e) "Urografin" and dextran T150; f) "Ficoll-Paque". The final preparation of lymphocytes obtained by "Urovison" and dextran T150 (d = 1.081) procedure was free from platelets and erythrocytes; lymphocytes degree of purity was found to be 98%. The sialic acids, hexoses and hexosamines contents were determined.

Animals↗

Glycoconjugates in salivary glands of rats during postnatal development.

In the salivary glands of young rats in different experimental conditions, we have found glycoconjugates containing hexosamines, hexoses, fucose and sialic acid in lower percentages than those found in adult rats. In the submandibular gland, the presence of sialic acid can be demonstrated only after the second week, whereas in the sublingual gland sialic acid is present in an amount roughly equal to half of what has been found in adult animals. The appearance of sialic acid in the submandibular gland is due to the development of the animals and not, as we had initially surmised to their diet.

Animals↗

Biochemical studies on repair cartilage resurfacing experimental defects in the rabbit knee.

UNLABELLED: Wounds penetrating articular cartilage to bone heal with cartilage described variably as either fibrous or hyaline. In the present study, such repair cartilage was induced in the rabbit for biochemical comparison with normal articular cartilage. The main collagen in the repair tissue after three weeks was type I. By six to eight weeks, type II had become predominant and continued to be enriched up to one year; but type I still persisted as a significant constituent of the repair tissue even after a year, so the repair cartilage never fully resembled normal articular cartilage. From radiochemical analysis, type II was determined to be the major collagen synthesized by the repair tissue after three to four weeks. After six months, the repair cartilage contained more collagen and less hexosamine than control cartilage, suggesting that the fibrous texture that often developed was due to a loss of proteoglycans rather than to a change in the type of collagen. CLINICAL RELEVANCE: Procedures capable of inducing the differentiation of authentic articular cartilage to resurface degenerated human joints would be invaluable. Surgical methods, such as drilling through to subchondral bone, are often attempted. It is not known, however, whether the cartilage that forms is true articular cartilage or, for example, fibrocartilage. The present experimental study in rabbits compared the properties of such repair cartilage with those of normal articular cartilage.

Animals↗

Analysis of an antistaphylococcal serum alpha globulin.

Previous studies in this laboratory have shown that normal human serum contains an alpha globulin possessing lethal and antirespiratory action for staphylococci. In this study further description of the antistaphylococcal macromolecule is presented. The antistaphylococcal protein was shown to be homogeneous by both isoelectric focusing in sucrose density gradients and sodium dodecyl sulfate electrophoresis. An analysis of the chemical composition of the antistaphylococcal serum protein indicated the alpha globulin to be a glycoprotein composed of 22.5% carbohydrate and 77.2% protein as determined by amino acid analysis. The total carbohydrates included 11.08% protein-bound hexoses. 0.86% hexosamines, 4.3% sialic acid and 6.3% fucose. The mean isoelectric point, determined by isoelectric focusing in the range pH 3-6, was 4.73. Molecular weight studies on Sephadex G-200 dextran gel columns calibrated with proteins and glycoproteins indicated the molecular weight of the antistaphylococcal macromolecule to be 55,000-74,000 daltons respectively. SDS-gel electrophoresis indicated the molecular weight of antistaphylococcal serum protein was 62,000. Thus the antistaphylococcal alpha globulin does not appear to be related to other known serum bactericidins.

Alpha-Globulins↗

Biosynthesis of elastin and other matrix-macromolecules in veinous arterial prosthesis.

Homologous saphenous veins where implanted in the arterial circilation (femoral artery) of dogs for various times (1 to 9 months, most data given for 3 months). After this period, the in vitro biosynthesis of intercullar matrix macromolecules was studied by incubating the veins in organ culture conditions in the presence of 14C-lysine for 3 days. A fractional extraction procedure was used to obtain representative macromolecular extracts for the determination of chemical composition (hydroxyproline, hexosamines) and radioactivity. Neosynthesis of elastin was considered as valid criteria for the adaptation of the veinous wall to the new (arterial circulatory) conditions. The chemical composition of the grafted veins was different from that of the nongrafted, controlateral saphenous veins suggesting a molecular remodeling of the grafted veinous wall. Radioactive lysine was incorporated in all macromolecular fractions of grafted and control veins. The specific radioactivity of the extracts obtained from grafted veins was higher than that obtained from the control veins. The only exception was the collagenase extract (containing mainly the polymeric collagen) which had a somewhat lower radioactivity in the grafted vein. The incorporation of lysine in the elastin fraction increased by a factor 10 in the grafted vein as compared to the non-grafted veins. Radioactive desmosine could be demonstrated in the elastin fraction. It appears therefore that the veinous wall could adapt its biosynthetic capacity to the new circulatory conditions by increasing considerably the biosynthesis of elastin. This is accompanied by an increase of the synthesis of other macromolecules and a significant remodeling of the macromolecular structure of the vessel wall.

Animals↗

Long-term fate and effects of exercise on sternal cartilage autografts used for repair of large osteochondral defects in horses.

Bilateral osteochondral defects (10 mm2 x 3 mm deep) were created on the distal articular surface of the radial carpal bone of ten, 2- to 3-year-old horses. One defect of each horse was repaired, using a sternal cartilage autograft (treated), and the other was left untreated (control). The horses were exercised on a high-speed treadmill at incrementally increased speed and duration over the course of 12 months. Horses were evaluated arthroscopically at 6 to 7 weeks, and clinical examinations were conducted weekly at exercise. Twelve months after surgery, carpuses of each horse were radiographed and clinically examined prior to euthanasia. A gross pathologic evaluation of each joint was conducted, and samples were collected for histologic, histochemical, histomorphometric, and biochemical evaluation. Radiographically, the grafted joints had more extensive evidence of arthropathy, and clinically, 8 of the 10 horses were more lame in the grafted limb. On the basis of histomorphometry, the repair tissue of the grafted defects contained a greater median percentage of hyaline cartilage (45%) than that of control defects (4.5%), and the control defects contained a greater percentage of fibrocartilage (82%) than did grafted defects (28.5%). A greater median percentage of repair tissue stained with safranin-O in the grafted defects (24.5%) than in the control defects (3.5%). On gross pathologic and histologic evaluation, repair tissue of the control defects had better continuity and was more firmly attached to the subchondral bone than was repair tissue of the grafted defects. Repair tissue of the grafted defects had extensive fissure and flap formation. Histologically, subchondral bone reactivity and fibroplasia was extensive in grafted joints. Repair tissue of grafted defects had a greater percentage of type II collagen (mean +/- SEM, 83.5 +/- 2.95%) than did controls (mean, 79.4 +/- 3.87%) that was not statistically significant. Hexosamine content was significantly higher (P < 0.05) in repair tissue of the grafted defect (mean, 28.9 +/- 3.00 mg/g of dry weight) vs control (mean, 20.6 +/- 1.85 mg/g of dry weight). On the basis of this experimental model, sternal cartilage autografts cannot be recommended at this time for repair of osteochondral defects in athletic horses.

Animals↗

Effect of 1,6-dihydro-2-[2-(2-methylpropoxy)anilino]-6-oxo-5-pyrimidinecarboxylic acid on gastric mucosal defensive factors and gastric secretion in rats.

1,6-dihydro-2-[2-(2-methylpropoxy)anilino]-6-oxo-5-pyrimidinecarbo xylic acid, (MAR-99, CAS 98772-05-5) (10-30 mg/kg i.g.) improved the reduction of gastric blood flow rate induced by the administration of 99.5% ethanol or acidified-acetylsalicylic acid (ASA). In addition, MAR-99 (3 x 10(-6)-3 x 10(-5) mol/l) protected dose-dependently the damage of epithelial cells induced by ulcerogenic agents such as ethanol or acidified-ASA. MAR-99 (1-10 mg/kg p.o.) prevented dose-dependently the reduction of hexosamine content in glandular stomach. Furthermore, MAR-99 (10-30 mg/kg i.g.) improved the decrease in gastric potential difference induced by 99.5% ethanol and acidified-ASA. MAR-99 (10-30 mg/kg p.o.) significantly inhibited the lesion formation induced by 99.5% ethanol and such effect of this compound was not attenuated by the pretreatment with indomethacin. Furthermore MAR-99 (10 and 30 mg/kg p.o.) had no effect on the prostaglandins (PGE2 and I2) contents in the stomach of normal rats. In pylorus-ligated rats, MAR-99 (3-100 mg/kg i.d.) showed a weak or no effect on acidity and pepsin activity in gastric juice, although this compound decreased dose-dependently the volume of gastric juice. In perfused stomachs, MAR-99 (30-100 mg/kg i.d.) slightly prevented the acid secretion induced by carbachol and pentagastrin. However, MAR-99 did not affect the acid secretion stimulated by histamine. These results indicated that anti-ulcer effect of MAR-99 was mainly due to maintenance of the gastric mucosal resistance.

Animals↗

Alteration in protein carbohydrate complexes in plasma of freshwater gastropod snail, Lymnaea luteola, challenged with foreign tissue implant.

Levels of protein bound hexose, hexosamine and proteins in ethanol precipitate of the body fluid and protein bound hexose and proteins in the perchloric acid filtrate of the body fluid of the snail L. luteola which received a xenoplastic implant in its cephalopedal sinus, are determined. The significant increase in protein bound hexose in the ethanol precipitate of bodyfluid in recipient snail as compared to sham operated and control snails is interesting. The results are discussed in the light of what is known about glycoproteins and their role in invertebrate immunity.

Animals↗

Histo-biochemical correlation in the oviduct of Bufo arenarum (Hensel).

A histo-biochemical correlation was carried out in oviducts of Bufo arenarum (Hensel), in trophic animals in the preovulatory period. Histochemical techniques were used to detect acidic mucoproteins, whereas complex mucopolysaccharides were biochemically assayed, thus simplifying the histologic methodology. The existence of acetylhexosamines, hexoses, phosphate and sialic acid in the oviduct was put in evidence through histochemical and biochemical methods. Results show a high content in sialic aicd, total phosphate and acetylhexosamines in the middle and terminal portions of the preconvoluted zone. Sialomucins, acetylhexosamines and hexosamines show a maximum in the last loops of the convoluted zone, coincident with clearly determined histologic areas. All components detected exhibit minimal values in the proximal and distal intermediate zones. Results found for phosphate show it is combined, and determines the reactivity to the stains used. This type of mucin has not been found in other species.

Animals↗

Isolation and physical characterization of hyaluronic acid prepared from bovine nasal septum by cetylpyridinium chloride precipitation.

Raw extract in 2 m CaCl2 of bovine nasal septum cartilage was eluted from 4 per cent agarose gel to give a "void volume" Fraction v-4, which was indistinguishable in composition and behavior on viscometric and sedimentation analysis from the densest fraction obtained by associative centrifugation in a cesium chloride density gradient. The sulfated proteoglycan was precipitated (Fraction A) by cetylpyridinium chloride from acidic solutions of Fraction v-4 or of dialyzed raw ectract. Neutralization under conditions of low ionic strength precipitated a further small fraction (B), which contained from 0.5 to 1 per cent of the uronic acid in the original extract. Analysis by associative and dissociative density gradient centrifugation demonstrated that Fraction B resembled in effective density known samples of hyaluronic acid from other sources. Gel chromatography of proteolytic digests of Fractions A and B on 6 per cent agarose indicated that cetylpyridinium chloride precipitation essentially separated sulfated proteoglycan (A) from hyaluronic acid (B). A viscosity-average molecular weight of about 5 x 10(5) was estimated for a sample of Fraction B purified in a dissociative (4 M guanidine hydrochloride + CsCl) density gradient. Sedimentation velocity data were consistent with this result. Analysis of hexosamines showed that the sample contained 96 per cent glucosamine, confirming the identification of hyaluronic acid. The proteoglycan fraction (A) resembled "subunits" in its sedimentation behavior.

Amino Acids↗