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)

Severe cutaneous ulceration may occur as a result of contrast media extravasation. We established a definitive animal model for assessing the cutaneous toxicity of commonly employed agents and used this model to evaluate possible antidotes to the effects of contrast media extravasation. The contrast agents studied were: meglumine/sodium diatrizoate 76%, meglumine iothalamate 60% and 43%, meglumine/sodium ioxaglate 60%, iohexol 350, and iopamidol 370, in varying volumes and osmolalities. Hypertonic saline (950 and 1900 mOsm/kg) also was injected. Agents were injected intradermally into BALB/c mice. The higher osmolality agents produced dose-dependent skin ulcerations. The lower osmolality agents failed to produce any skin lesions after the same volume doses. Hypertonic saline produced skin toxicity in a dose-dependent fashion similar to hyperosmolar contrast agents. Three antidotes were tested: hyaluronidase, topical heat, and topical cold. Hyaluronidase significantly reduced skin toxicity when injected immediately following contrast injection. Cold also significantly reduced skin toxicity, while heat caused no improvement.
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PMID:Cutaneous ulceration due to contrast extravasation. Experimental assessment of injury and potential antidotes. 202 47

Epithelial cells can be isolated from the small intestine of chickens by a procedure involving hyaluronidase treatment of the intact tissue. The isolated cells retain a high degree of functional activity as assessed by the formation of 70-fold gradients of alpha-MG. Stability of the sugar gradients reflects maintenance of stable electrochemical Na+ gradients across the plasma membrane. The cells can be used to evaluate the properties of Na(+)-dependent sugar transport, Na(+)-independent sugar transport, ion transport, metabolism, membrane potentials, and the integration of these events, all of which are important to achieving a stable sugar gradient.
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PMID:Isolation of intestinal epithelial cells and evaluation of transport functions. 207 96

A recent hypothesis for the cellular mechanism of fluid secretion by lacrimal acini has been based, in part, on the results of subcellular fractionation analyses of lacrimal gland fragments which had been incubated for a brief period in vitro. An important assumption in those studies was that the ion transporters and neurotransmitter receptors measured in isolated subcellular fractions were associated with membranes derived from the acinar cells, since these comprise the bulk of the lacrimal gland mass. This study was undertaken to validate this assumption. Acinar complexes were isolated from rat exorbital lacrimal glands by digestion with collagenase, hyaluronidase, and DNase. Although terminal intralobular duct segments and myoepithelial cells were occasionally noted, the preparations appeared to be free of larger ducts, blood cells, blood vessels, and interstitial cells. Acinar cells were then disrupted, and the homogenates underwent the fractionation procedure used previously for lacrimal gland fragment preparations. This procedure involved a sequence of analyses by differential sedimentation, isopycnic centrifugation on sorbitol gradients, and partitioning in dextran-polyethyleneglycol two-phase systems. Calculated initial specific activities for sodium/potassium adenosinetriphosphatase (Na+/K(+)-ATPase), alkaline phosphatase, acid phosphatase, and succinate dehydrogenase were identical to those obtained from fragment preparations. Major membrane populations resolved by the sequential analyses, including one believed to represent endoplasmic reticulum membranes, two believed to be derived from the acinar cell basal-lateral membrane, and two believed to be derived from the Golgi complex, corresponded closely to populations resolved from lacrimal fragment preparations. In addition to validating the previous use of lacrimal gland fragment preparations in studies of acinar cell function, these results suggest that preparations of isolated lacrimal acini will be useful for future work on neurotransmitter-receptor regulation and basal-lateral plasma membrane dynamics in the lacrimal gland.
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PMID:Analytic subcellular fractionation of acini from rat lacrimal gland. 217 90

The foregoing sections have reviewed the experimental studies and clinical anecdotes describing potential pharmacologic antidotes to extravasations of vesicant anticancer agents. Numerous prior reviews have also suggested specific antidotes or very conservative, non-pharmacologic approaches. Many antidotal approaches to extravasation have not been experimentally validated and thus, few 'antidotes' share a rationale which is founded on positive experimental and clinical studies. However, using this criteria, a few active antidotes can be distilled from the literature. These are outlined in Table 6. These antidotes include isotonic (1/6 M) sodium thiosulfate for mechlorethamine (and optionally for cisplatin), hyaluronidase for the vinca alkaloids (and optionally for epipodophyllotoxins such as etoposide), and cooling with very topical DMSO and low dose hydrocortisone for the anthracyclines. For the alkylating agent mitomycin C, topical DMSO has been effective experimentally but has not yet received clinical validation, at least in published studies. Nonetheless, the severity of mitomycin C ulcerations and the documented safety of topical DMSO in the small series of doxorubicin extravasation patients argues for its use when mitomycin extravasates in the clinic. Furthermore, except for DMSO, all of these extravasation antidotes are listed in the official FDA-approved package inserts for each vesicant agent. Thus, the inserts for vincristine and vinblastine specify hyaluronidase, for doxorubicin, glucocorticosteroids, and for mechlorethamine, sodium thiosulfate. New studies are clearly needed to clarify the role of topical DMSO with anthracyclines and mitomycin C. In addition, efforts should be made to begin clinical development of radical dimers such as DHM3 which can directly inactivate quinone-containing vesicants like doxorubicin and mitomycin C. Although the incidence of chemotherapy extravasation may be lessened with vascular access devices, it nonetheless, continues to comprise a serious and highly litigious area of oncology practice. This commands continued extravasation intervention studies and diligent prevention when ever possible.
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PMID:Antidotes to vesicant chemotherapy extravasations. 218 47

Separation and recombination experiments were made with manually or trypsin-dissociated dental papillae (day 15, 16, 17, 18 in utero and 2, 7, 14 postnatal) and manually isolated hard tissues of the third molar crown (14 postnatal days). Several series of hard tissues were further treated with citric acid, hyaluronidase or sodium hypochlorite. The recombinations were transplanted into the subcutaneous tissue of new-born mice. Grafts were removed 7, 14 and 21 days later and prepared for light and electron microscopy. Whatever the age of the papilla and whatever the treatment of the crowns, well-characterized odontoblasts differentiated and deposited new layers of tubular dentine, except when the recombined dental papilla was 15 days old. These findings indicate that odontoblasts are very early committed (since day 16 in utero) and that they may differentiate in dental papillae in contact with chemically altered dentinal matrices.
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PMID:Differentiation of odontoblasts in mouse dental papillae recombined with normal or chemically-treated dentinal matrices. 228 4

Africanized honeybees (HBs) pose a hazard to both normal and sting-sensitive subjects in certain areas of Central and South America, and it is predicted that they will soon be present in the southern United States as well. Using an electrical stimulation device, we collected Africanized HB venom (AHV) in Venezuela and European HB venom (EHV) in Louisiana. These venoms, along with commercial European HB venom (CHV), were compared by thin-layer isoelectric focusing and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The Coomassie brilliant blue and silver-stained banding patterns of AHV and EHV were essentially identical to CHV. Western blots were prepared from SDS-PAGE gels and tested with pooled sera from EHV-sensitive subjects and then radiolabeled antihuman IgE. The resulting autoradiographs revealed similar banding patterns among EHV, AHV, and CHV. RAST-inhibition studies were performed with solid-phase CHV and pooled sera from EHV-sensitive subjects. The specific allergenic activities of the three HB venoms (allergy units per milligram of protein) were comparable. By RAST-inhibition assay with solid-phase, highly purified individual venom components, AHV and EHV both contained phospholipase A2, hyaluronidase, and high-molecular-weight allergens. The increased morbidity after Africanized HB stings is likely related to their more defensive behavior during which many bees react by stinging rather than to biochemical or allergenic differences between AHV and EHV.
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PMID:Biochemical and immunochemical comparison of Africanized and European honeybee venoms. 229 9

The onset of akinesia of the extraocular muscles was assessed after peribulbar block with a plain or pH-adjusted solution of 0.75% bupivacaine and hyaluronidase. Thirty-five patients were randomly assigned to receive either 0.75% bupivacaine with hyaluronidase 15 units/ml (pH 5.45 +/- 0.12) or the same pH-adjusted solution (0.15 mEq sodium bicarbonate per 30 ml of 0.75% bupivacaine to give a final pH of 6.82 +/- 0.09) in a double-blind, prospective manner. Onset of akinesia was determined to the nearest minute. Supplemental injections were given after 20 min in the event of incomplete akinesia. The group receiving pH-adjusted bupivacaine had a statistically faster onset time for complete akinesia than did the control group (5.3 +/- 1.2 min vs. 14.3 +/- 2.3 min, respectively; P less than 0.001). Five of 17 patients in the control group required a supplemental injection, whereas only one of 17 patients in the treatment group had a supplemental block at 20 min (P less than 0.05). Thus, pH adjustment of a solution of bupivacaine and hyaluronidase with sodium bicarbonate hastens the onset time and improves the initial success rate of peribulbar block.
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PMID:pH-adjusted bupivacaine and hyaluronidase for peribulbar block. 240 35

Partial degradation products of sodium hyaluronate produced by the action of testicular hyaluronidase induced an angiogenic response (formation of new blood vessels) on the chick chorioallantoic membrane. Neither macromolecular hyaluronate nor exhaustively digested material had any angiogenic potential. Fractionation of the digestion products established that the activity was restricted to hyaluronate fragments between 4 and 25 disaccharides in length.
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PMID:Angiogenesis induced by degradation products of hyaluronic acid. 240 40

The binding of a hyaluronic acid-binding glycoprotein, hyaluronectin (HN), isolated from human brain, to hyaluronic acid (HA) was investigated with the enzyme-linked immunosorbent assay technique using plastic microtest plates coated with a 50 mg/liter solution of HA in 0.1 M bicarbonate. Optimum conditions for HN binding to HA were in 0.2 M NaCl buffered with 0.1 M sodium phosphate at pH 7. An assay for HA in solution was set up exploiting the fact that HN binding could be inhibited by soluble HA. HA was preincubated for 1 h in a test tube with a 30-ng/ml HN solution (v/v) in the buffer containing 0.1% bovine serum albumin. Incubation on HA-coated microtest plate lasted 4 h and maximum sensitivity was achieved when incubation was carried out at 4 degrees C. HN bound to the plate was revealed by means of alkaline phosphatase-conjugated anti-HN antibodies. The test was used to measure HA inhibitory activity after depolymerization by ferrous ions. No difference was found between inhibitory activity or smaller fragments and that of high-molecular-weight HA. The assay was applied to determination of HA in sera. Specificity was demonstrated by Streptomyces hyaluronidase digestion of reactive material in sera. Other glycosaminoglycans did not interfere with the assay. Recovery of HA was good and intra- and interassay variation coefficients were 6 +/- 2.2 and 12%. In 103 blood donor sera, HA was found at 22.4 +/- 16.7 micrograms/liter. HA was elevated in most of the cancer patient sera tested.
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PMID:Immunoenzymoassay of the hyaluronic acid-hyaluronectin interaction: application to the detection of hyaluronic acid in serum of normal subjects and cancer patients. 241 43

A direct Schiff reaction of elastic tissues has been known for many years, but the nature of the native aldehyde-rich components has not been clear. In this study, chicken, quail, and rat embryos and adult rat lung, aorta, and kidney were fixed in methacarn or in a formalin solution, embedded in paraffin, and sections of 8-10 micron obtained. Rehydrated sections were incubated for various periods in solutions of the enzymes chondroitinase ABC, clostripain, collagenase, elastase, heparatinase, hyaluronidase, subtilisin Carlsberg ("protease"), or trypsin, and in solutions of phosphomolybdic acid or sodium borohydride. After incubation, sections were placed, without prior oxidation, in Schiff's reagent, and were ultimately observed and photographed in transmitted light or with blue or green epifluorescence. A Schiff-positive substance was found, always and exclusively, in elastic tissues of the vasculature and lungs, which was hydrolyzed by the proteolytic enzymes to an extent that ranged from complete loss of Schiff reaction in minutes (trypsin) to no loss of Schiff reaction in 22 hr (clostripain). The Schiff-reactive protein preceded the time of appearance of elastin in the early embryos. We conclude that the aldehyde-rich protein responsible for this reaction is a harbinger of elastogenesis in vivo and speculate that it may represent the elastic microfibril or a component thereof.
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PMID:A new interpretation of the direct Schiff reaction of elastic connective tissue. 244 56


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