Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.2.1.36 (hyaluronidase)
4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hyaluronan (HYA) is a large glycosaminoglycan with a high capacity to immobilize water. Increased levels of HYA have previously been observed in plasma as well as in affected tissues in various inflammatory conditions. The morphological localization of HYA has, however, not been described in normal or rejected human kidneys. Using a recently developed method for localization of HYA in tissue sections by means of a biotin-labeled hyaluronan binding protein used as a probe, we have now investigated the distribution of HYA in normal and irreversibly rejected human kidneys. In the normal kidney HYA was essentially confined to the medulla. In the rejected kidneys increased amounts of HYA were observed primarily in the cortex and in sclerotic vessels. Incubating tissue sections with hyaluronidase abolished the staining for HYA, showing the specificity of the staining procedure. The increased amounts of HYA of the rejected kidney may play a role in local edema formation, and thereby alter graft function.
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PMID:The localization of hyaluronan in normal and rejected human kidneys. 238 92

Many glioma-derived cell lines have the capability of escaping cell-mediated immune attack. One mechanism of escape is the secretion of a hyaluronidase-sensitive mucopolysaccharide coat by these cells. This coat prevents contact and tumor cell killing by specific cytolytic allogeneic lymphocytes. The production of the coat by the tumor cells is stimulated by a macromolecular factor released by peripheral blood mononuclear (PBMC) cells in culture. We have examined the morphologic and ultrastructural features of this extracellular matrix. Three coat-producing lines were studied. Under phase contrast light microscopy, the coat is a clear pericellular 'halo'. To stain this zone, ruthenium red and Alcian Blue 8 G stains, which bind to acid mucopolysaccharides (to a large extent, hyaluronic acid), were used. The two stains produced similar results. With light microscopy, a weblike pattern of stain was evident throughout the halo region. With transmission electron microscopy, staining was found along the plasma membrane of the glioma cells and their microvilli, stretching in long, branching filaments from these surfaces and, in some instances, from one microvillus to the next. Since mucopolysaccharide matrices have a large aqueous component, it was necessary to determine whether dehydration alters the stain pattern. Therefore, undehydrated ruthenium red stained specimens from each culture were embedded in Quetal 651 (Ted Pella, Inc., Tustin, CA), a water soluble plastic. No morphologic differences were noted between the hydrated and dehydrated specimens. This study indicates that numerous long microvilli and a secreted mucopolysaccharide matrix are important structural elements of the lymphocyte-stimulated tumor cell halo in vitro. The mechanism by which the PBMC factor stimulates coat formation and the importance of the coat in in vivo tumor defenses remain to be elucidated.
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PMID:Ultrastructural features of the lymphocyte-stimulated halos produced by human glioma-derived cells in vitro. 242 Sep 43

Eighteen specimens of palatal mucosa were taken from 17 human subjects. Paraffin-wax sections were stained by routine methods and with various techniques to demonstrate glycosaminoglycans (GAG). In some sections, GAG were removed by selective degradative procedures before staining. Beneath all rugae, there were myxoid areas varying in size and marginal definition. Collagen fibres were few; elastic and reticulin fibres were numerous in a minority of sections. Alcianophilia at pH 2.5, preventable by streptomyces hyaluronidase digestion, suggested the presence of hyaluronic acid beneath the rugae. Alcian-blue staining at pH 1.0 and with the critical electrolyte concentration method using 0.5 M MgCl2 did not distinguish the myxoid tissue from the surrounding connective tissue and could be prevented by digestion with testicular hyaluronidase or chondroitinase ABC. Chondroitin sulphate and, or dermatan sulphate thus may be present but were not localized to the myxoid tissue. This unusual zone of loose connective tissue may act as a physical buffer resisting the local effects of high loads by allowing reversible extrusion of the water.
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PMID:Histological localization of myxoid tissue in normal human palatal mucosa and its glycosaminoglycans. 244 96

The venom of the tarantula Eurypelma californicum was analysed biochemically, the components were isolated and characterized. The pH value of the crude venom is 5.3 +/- 0.3. After dilution with distilled water, UV-absorption spectra showed a single maximum at 258 nm (pH ca. 7.0). A second maximum at 328 nm emerged above pH 8.0. Protein concentration of the venom is ca. 65 mg/ml. After Coomassie staining SDS-PAGE patterns show three major bands with apparent molecular masses around 40 kDa, 4.3 kDa and 1.3 kDa besides some weak high molecular protein bands. The following low-molecular mass constituents were determined in the crude venom: ATP, ADP, AMP, glutamic acid, aspartic acid, gamma-aminobutyric acid, glucose and the ions potassium, sodium, calcium, magnesium and chloride; the osmolality was 361 micro0smol/ml. The LD50 value for female cockroaches was 0.15 microliters venom per g body weight and for male cockroaches 0.4 microliters venom per g body weight. Separation of the crude venom by gel chromatography yielded four elution peaks. Peak I contains the enzyme hyaluronidase. The activity is 200-900 U/microliters. Peak II contains a mixture of toxic peptides. Peak III contains the 1.3-kDa components of SDS-PAGE and peak IV mainly contains ATP. Venom proteins including the enzyme hyaluronidase were precipitated by 5% trichloroacetic acid. The supernatant was separated by HPLC into 13 fractions. Fraction 1 contains glutamic acid, aspartic acid, gamma-aminobutyric acid and ATP; fraction 2 contains ATP, ADP and AMP as well as a component 2' visible in SDS-PAGE as 1.3-kDa band and consisting of spermine and tryptophan; fraction 3 contains ATP and an unknown component 3'; fractions 4-6 also show a 1.3-kDa band in SDS-PAGE, fraction 4 being tyrosylspermine and fractions 5 and 6 containing compounds of spermine and aromatic molecules; fraction 7 contains a peptide which lacks aromatic amino acids, it was sequenced from the N-terminus; fractions 8-13 contain very similar toxic peptides. The peptides in fractions 11 and 12, labeled ESTX for Eurypelma spider toxin, were cleaved with different enzymes and sequenced. They differ in one amino acid in position 26. Homologies with scorpion toxins and with a toxin of the spider Segestria florentina were found.
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PMID:Tarantula (Eurypelma californicum) venom, a multicomponent system. 274 56

We have determined whether changes in lung hyaluronan content affect extravascular water in lungs of unanesthetized rabbits. Three groups of experiments were performed. In group 1 (n = 12), no infusions were given; in group 2, nine pairs of rabbits received either intravenous hyaluronidase (750 U.kg-1.min-1) or an equivalent volume of saline; in group 3, nine pairs of rabbits received either hyaluronidase or saline, followed by intravenous saline infusion amounting to 24% of body weight. At the end of each experiment, one lung was analyzed for extravascular lung water by the wet-dry method. Except for group 3, in all animals the other lung was analyzed for hyaluronan content by a method that involved hydrolyzing lung hyaluronan with fungal hyaluronidase to release reducing N-acetyl glucosamine groups, which were quantified. In group 1, lung hyaluronan, which varied from 50 to 159 micrograms/g dry wt (mean 106 +/- 35 micrograms/g dry wt), significantly correlated with variation in extravascular lung water (mean 4.2 +/- 0.3 g/g dry wt). In group 2 rabbits given hyaluronidase, lung hyaluronan was 40% lower and extravascular lung water was 14.6% lower than in paired controls (P less than 0.01). In group 3, volume expansion did not affect lung water, except after hyaluronidase when lung water was 47% higher than paired controls. We conclude that in the lung the content of hyaluronan is one of the determinants of extravascular water content.
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PMID:Hyaluronan affects extravascular water in lungs of unanesthetized rabbits. 274 21

The vitreous gel is primarily composed of collagen, hyaluronic acid, and water (98-99%) and can break down into a liquid state devoid of collagen. The liquifaction of vitreous gel that occurs with age and in certain other disease states is believed to be important in the pathogenesis of retinal tears and detachments. The authors report measurements of water proton relaxation times and water proton nuclear magnetic resonance (NMR) imaging to study the process of vitreous liquifaction in extracted vitreous and in the intact bovine eye. A comparison is made between macroscopic viscosity, longitudinal (T1) and transverse (T2) relaxation times obtained on an NMR spectrometer and proton NMR images. Vitreous liquifaction as measured by a decrease in macroscopic viscosity resulted after treatment of vitreous with collagenase and to lesser degree with hyaluronidase. A shortening of relaxation times accompanied the drop in viscosity. An area of brightness or increased proton signal intensity corresponding to a focus of liquifaction was seen by NMR imaging only after injection with collagenase. The authors believe NMR imaging to be a useful new diagnostic modality by which vitreous liquifaction can be studied in the intact eye. The vitreous provides a new model for studying changes in proton relaxation times of protein solutions in biologic systems.
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PMID:Study of vitreous liquifaction by NMR spectroscopy and imaging. 298 51

We undertook studies in the isolated perfused rat lung to determine 1) the effects of endothelial charge neutralization with the polycation protamine sulfate on microvascular permeability, lung water, and anionic ferritin binding to the endothelium and 2) the role of heparan sulfate and hyaluronate, negatively charged cell surface glycosaminoglycans, on permeability. Capillary permeability was determined by tissue 125I-albumin accumulation in isolated perfused rat lungs. In control lungs the 5-min albumin uptake was 0.50 +/- 0.05 cm3.s-1.g dry tissue-1 X 10(-3). It was increased by 132 +/- 7.8% (P less than 0.001) by protamine (0.08 mg/ml) and 65 +/- 12% (P less than 0.01) by heparinase (5 U/ml), whereas hyaluronidase (25 NFU/ml) was without effect. In control lungs total water was 4.83 +/- 0.15 ml g/dry tissue. Protamine increased lung water 12 +/- 2% (P less than 0.05). Heparinase caused a 9 +/- 3% increase (P less than 0.05), and hyaluronidase had no effect. Electron microscopy demonstrated that protamine increased anionic ferritin binding to the surface of endothelial cells. We conclude that protamine sulfate neutralization of negative charge in the pulmonary microcirculation leads to increased microvascular permeability. Heparin sulfate may be responsible for this charge effect.
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PMID:Effects of protamine, heparinase, and hyaluronidase on endothelial permeability and surface charge. 369 32

Effects of hyaluronidase on myocardial water content and distribution, and on coronary vascular hemodynamics and endothelial cell transport function were assessed in isolated rabbit hearts during 3.5 hours of reperfusion after 30 minutes of global, no-flow ischemia. In nonischemic control hearts, perfusion pressure, left ventricular end-diastolic pressure, maximum +dP/dt, and intravascular clearance of radiolabeled albumin remained constant during 5 hours of continuous perfusion, while the mean-transit time and vascular into extravascular space clearance of radiolabeled albumin increased 1.5X and 2.5X baseline, respectively. During reperfusion after 30 minutes of no flow, perfusion pressure increased 53% and interstitial fluid volume increased 2-fold, while left ventricular end-diastolic pressure and maximum +dP/dt returned to control levels. The rate of intravascular clearance of radiolabeled albumin decreased 38%, and the mean-transit time and vascular-into-extravascular space clearance of albumin increased approximately 3X and 5X baseline, respectively. Hyaluronidase blocked the ischemia-reperfusion-induced increases in total water content and in interstitial fluid volume and reduced the increases in perfusion pressure and mean-transit time of radiolabeled albumin by 40% and 45%, respectively, but did not prevent the increase in albumin vascular-into-extravascular space clearance and the decrease in albumin clearance from the coronary vasculature. These findings indicate that hyaluronidase does not prevent ischemia-reperfusion-induced increases in albumin permeation of the coronary vasculature, and suggest that its protective effect on ischemic myocardium is mediated, instead, by reducing interstitial edema and vascular resistance.
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PMID:Hyaluronidase does not prevent deterioration of vascular functional integrity during reperfusion after no-flow ischemia in isolated rabbit hearts. 400 93

The rate of transfer of intravitreally injected tritiated water from the mid vitreous to the choroid is significantly increased after depolymerization of vitreous hyaluronic acid by injected hyaluronidase. The significance of this finding is discussed in relation to such conditions as retinal detachment and reattachment.
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PMID:Effect of intravitreal hyaluronidase on the clearance of tritiated water from the vitreous to the choroid. 401 49

Sulfonation of periodate-oxidized vicinal hydroxyl groups on a polysaccharide backbone allows binding of toluidine blue (aldehyde bisulfite-toluidine blue or ABT staining) with a concurrent metachromatic shift of the dye's absorption peak from 630 nm (monomer) to 580 nm (isolated dimer interaction at vicinal sulfonate groups) or 540 nm (dye polymer interaction). A molar absorptivity of 2.358 +/- 0.134 X 10(4) at 540 nm for polymeric toluidine blue O chloride (TB) aggregates was determined by spectrophotometry of TB bound to hyaluronic acid (HA) and sulfonated glycogen (SG) in water. Microspectrophotometry of ABT stained frog rod outer segments (FROS) showed spectra similar to TB in aqueous HA and SG solutions with absorbances corresponding to 0.063 M dye bound to sugar. Given two dye molecules bound per sugar residue and a rhodopsin concentration of 3.25 mM in FROS, the above indicates 10 stainable sugars per rhodopsin are contained in these cells. Half of these sugars are sensitive to hyaluronidase digestion implying 5 glycosaminoglycan (GAG) repeating units and 5 stainable oligosaccharide sugar residues per rhodopsin in FROS. The GAGs in FROS appear to be primarily HA. Birefringence measurements at 475 nm indicate that this HA and the oligosaccharide of rhodopsin are anisotropically oriented in these cells.
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PMID:Acid polysaccharide content of frog rod outer segments determined by metachromatic toluidine blue staining. 618 48


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