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

---

Query: EC:3.2.1.17 (lysozyme)
21,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Incorporation of control valves into a previously described device enabled us to regulate the formation of 8 suction blisters on the upper surface of the forearm in adult human volunteers. After the removal of the raised epidermis and blister fluid, uniform areas of denuded dermis were obtained by placing hollow adhesive ring reinforcers onto each of the regions of exposed dermis. Single or double nitrocellulose filters were then placed onto each of the areas of moistened, exposed dermis. The chemotactic tripeptide FMLP was incorporated into 1% agarose containing 0.1% bovine serum albumin (BSA) to give a concentration range of 10(-8) M to 10(-6) M FMLP. In control systems the FMLP was omitted. Cylindrical agarose blocks +/- FMLP were then placed onto the filters and encased in individual perspex cups glued firmly onto the skin. The filter(s) and agarose blocks were replaced at 2 h intervals and polymorphonuclear leucocyte (PMNL) migration onto (single filter) and into (double filter) the filters was measured by microscopic enumeration or according to the amount of myeloperoxidase (MPO) and lysozyme in the supernatants of filters immersed in 0.1% Triton-X for 10 min to lyse the PMNL. Microscopic enumeration was found to be unsuitable but the method based on MPO and lysozyme release from filter-associated PMNL was rapid, accurate and reproducible. Detectable PMNL migration (greater than 90%) occurred at 3-4 h and was maximal at 8-10 h. This pattern was observed for both the control and FMLP-containing systems. However, PMNL migration was significantly greater in FMLP-exposed dermis. FMLP at 10(-6) M was found to promote maximal PMNL migration. Significantly greater MPO and lysozyme activities were observed with the double filter system. This method is suitable for the objective quantitation of PMNL migration in vivo.
...
PMID:An objective filter-based, enzymatic method for the in vivo measurement of the migration of human polymorphonuclear leucocytes. 299 30

Lidocaine is used extensively in coronary care units, yet the effect of lidocaine infusions on neutrophil function has not been known. Lidocaine and other local anesthetics impair leukocyte antibacterial functions when added in vitro. We found that lidocaine added to human neutrophils in vitro markedly impaired the release of superoxide anion (O2-) and the granule enzymes lysozyme and myeloperoxidase after stimulation by phorbol myristate acetate or opsonized zymosan. We then measured production of O2- during stimulation of neutrophils from eight normal subjects, five coronary artery disease patients not receiving lidocaine and 13 coronary artery disease patients receiving lidocaine infusions for at least 12 hr. Release of O2- by cells from lidocaine-treated patients (14.2 +/- 3.8 nmol/2.5 X 10(6) neutrophils per 15 min) was significantly lower than from cells of the normal subjects (78.4 +/- 7.2 nmol; P less than .001) and the coronary patients not receiving lidocaine (70.6 +/- 4.0 nmol; P less than .001). Bactericidal assays at a high concentration (2 mg/ml) of lidocaine demonstrated slight reductions in 2 hr killing rates for Escherichia coli (70% with lidocaine vs. 95% control). Inhibition by lidocaine of the release of toxic oxygen metabolites from neutrophils could potentially reduce infarct size in patients with acute myocardial infarction; but as there is only a slightly reduced ability to kill bacteria, increased susceptibility to infections is unlikely although it cannot be excluded.
...
PMID:Reduced neutrophil superoxide anion release after prolonged infusions of lidocaine. 299 33

Human subjects submitted to treatment with morphine show a severe depression of phagocytosis, killing properties and superoxide production both of their polymorphonuclear leukocytes and monocytes. Polymorphonuclear leukocyte adherence, chemotaxis, random migration, myeloperoxidase content, lysozyme content and lymphocyte Rosette E formation were poorly influenced. Methadone-treated subjects show a similar effect at phagocytic level but far less evident. These results confirm those previously found in animals and reinforce the evidence of a depressive role of morphine on phagocytic physiology.
...
PMID:Morphine and methadone impact on human phagocytic physiology. 300 Sep 61

Platelet factor (PF4) prepared from human outdated platelets by heparinagarose affinity chromatography was confirmed to be chemotactic for human neutrophils and in a concentration-dependent fashion caused significant release of lysosomal enzymes (myeloperoxidase, lysozyme, beta-glucuronidase) from human neutrophils treated with cytochalasin B. Lysosomal enzyme release from PF4-stimulated neutrophils was rapid and reached a plateau by 1-3 min. PF4 did not cause release of the cytoplasmic enzyme lactate dehydrogenase which indicates that exocytosis of granule-containing lysosomal enzymes did not result from cytolysis. In contrast, superoxide anion generation from human neutrophils stimulated with PF4 was undetectable even at the highest PF4 concentration tested (2 X 10(-5) M). Pretreatment of neutrophils with PF4 caused significant increased adherence of neutrophils to plastic surfaces and cultured pulmonary artery endothelial cells. The concentration of PF4 that elicited neutrophil chemotaxis, lysosomal enzyme release and increased adherence is slightly higher than those concentrations found in normal human sera. However, the results suggest that PF4 may be an important mediator in neutrophil-platelet interactions and the induction of acute inflammation especially at sites of platelet microthrombi where the concentration of PF4 would be elevated.
...
PMID:In vitro effects of platelet factor 4 on normal human neutrophil functions. 300 56

Ten patients were treated with repeated leukophereses performed one to three times per week for 2-5 weeks. Two of the patients was cleared completely, four exhibited regression of more than one-half of the lesions, and four showed only a slight improvement. The therapy did not markedly affect the granulocyte count in peripheral blood, and the beneficial clinical response was not related to the number of polymorphonuclear leukocytes (PMNs) removed by leukophereses. During therapy, the activities of elastase, cathepsin G, lysozyme, and myeloperoxidase in PMNs were determined by spectrophotometry. PMNs isolated using a Haemonetics 30 blood-cell separator were about 50% deficient in these activities in comparison to cells obtained directly from peripheral blood. Thus, leukopheresis induces a marked degranulation of PMNs. Repeated leukophereses were found to generate significant variations in the activities of circulating PMN granule enzymes and in the levels of acid-soluble proteins. Remission or great improvement were observed in patients who, during therapy, exhibited decreased PMN elastase and cathepsin G activities, whereas a poor clinical response was accompanied by high enzymatic activities.
...
PMID:Leukopheresis for treatment of psoriasis: is therapeutical benefit related to reduced activities of neutral proteinases of polymorphonuclear leukocytes? 300 6

Aggregated immunoglobulin G (AggIgG) caused a concentration-dependent extracellular release of granule-associated lysozyme and myeloperoxidase (MPO) from human neutrophils. Generation of the 5-lipoxygenase product of arachidonic acid (AA) metabolism, 5(S),12(R)-dihydroxy-6,14-cis,8,10-trans-eicosatetraenoic acid [leukotriene B4 (LTB4)], by neutrophils is exposed to AggIgG occurred in the presence but not absence of exogenous AA. U-60,257B (piriprost potassium), an inhibitor of leukotriene synthesis, caused a dose-related suppression of LTB4 production and granule exocytosis by AggIgG-treated cells. These data suggest that a lipoxygenase product of AA metabolism may mediate AggIgG-induced phagocytic release of granule constituents from neutrophils.
...
PMID:A possible requirement for arachidonic acid lipoxygenation in the mechanism of phagocytic degranulation by human neutrophils stimulated with aggregated immunoglobulin G. 301 Sep 68

Aggregated immunoglobulin G (AggIgG) induced a time- and concentration-dependent phagocytic release of granule-associated lysozyme and myeloperoxidase (MPO) from human neutrophils. Degranulation was significantly enhanced in the presence of calcium or magnesium, and maximum granule exocytosis was observed when both divalent cations were present. AggIgG-stimulated enzyme release was inhibited with the intracellular calcium antagonist, TMB-8[8-(N,N-diethylamino)-octyl-(3,4,5-trimethoxy)benzoate] in the absence of extracellular calcium. DIDS (4,4'-diisothiocyano-2,2'-disulfonic acid stilbene), a permeant anion channel blocker, also suppressed AggIgG-induced degranulation. Cycloheximide, an inhibitor of protein synthesis, enhanced granule exocytosis from AggIgG-treated neutrophils. Two inhibitors of transmethylation reactions, 3-deazaadenosine (3-DZA) and homocysteine thiolactone (HCTL) in combination, suppressed AggIgG-elicited granule enzyme release. These data indicate that AggIgG is a useful probe for investigating the requirements for phagocytic enzyme release from human neutrophils.
...
PMID:Characteristics of aggregated immunoglobulin G as an immunologic phagocytic stimulus for granule enzyme release from human neutrophils. 301 67

Previous studies on the fractionation of human neutrophil granules have identified two major populations: myeloperoxidase (MPO)-containing azurophil, or primary, granules and MPO-deficient specific, or secondary, granules. Peripheral blood neutrophils from individual donors were lysed in sucrose-free media by either hypotonic shock or nitrogen cavitation. Using a novel two-gradient Percoll density centrifugation system, the granule-rich postnuclear supernatant was rapidly (ten minutes) and reproducibly resolved into 13 granule fractions (L1 through L8 and H1 through H5). Granule flotation and recentrifugation experiments on both continuous, self-generated and multiple-step gradients using individual and mixed isolated fractions demonstrated that the banding patterns were isopycnic and nonartifactual. Isolated granules were intact based on the findings that biochemical latency of several granule enzymes was greater than 95%, and thin-sectioned electron micrographs demonstrated intact granule profiles. Biochemical analyses of the granule marker proteins MPO, beta-glucuronidase, lysozyme, and lactoferrin indicated that a number of the fractions were related to the major azurophil and specific granule populations. Lactoferrin was found in ten of 13 fractions (L1 through L8, H1 to H2), whereas MPO was found in every fraction. Consistent with these biochemical data, all fractions exhibited varying degrees of heterogeneity based on ultrastructural morphology and cytochemistry, including diaminobenzidine (DAB) reactivity for peroxidase and periodate-thiocarbohydrazide-silver proteinate (PA-TCH-SP) staining for complex glycoconjugates. A variable but significant percentage (23% to 70%) of the granules in fractions L1 through L8 and H1 and H2 showed DAB reactivity, while about 90% of the granules in fractions H3 through H5 were peroxidase positive. These results demonstrated that DAB-reactive granules spanned the entire range of granule size and density. Ultrastructural PA-TCH-SP staining of isolated granule fractions revealed patterns similar to those of granules in intact neutrophils at different stages of development. Granules from human acute promyelocytic leukemia cells (HL-60) exhibited a surprisingly low density compared with typical azurophil granules from normal, mature neutrophils. The data suggest that both functional and maturational differences contribute to granule heterogeneity, and provide a new practical and conceptual framework for further defining the phenomenon of neutrophil granule heterogeneity.
...
PMID:High resolution of heterogeneity among human neutrophil granules: physical, biochemical, and ultrastructural properties of isolated fractions. 301 86

Reduced bacterial killing by polymorphonuclear leucocytes has been reported in patients with diabetes mellitus. Whether this is due to reduced content of bactericidal granular proteins has not been determined. We therefore immunochemically measured the content of myeloperoxidase, lactoferrin, lysozyme, cathepsin G and elastase in polymorphonuclear leucocytes from 50 insulin-treated diabetic patients. The peroxidase activity was also measured. Normal contents of myeloperoxidase and lactoferrin as well as normal peroxidase activity were found. The average contents of cathepsin G, elastase and lysozyme were 2.5, 3.2 and 2.6 micrograms/10(6) polymorphonuclear leucocytes, respectively, and thus 14, 45 and 18% higher than the contents of normal polymorphonuclear leucocytes. The results indicate that reduced intracellular killing of bacteria demonstrated in previous studies in diabetic patients does not appear to be related to a reduction in the content of bactericidal proteins.
...
PMID:Bactericidal proteins and neutral proteases in diabetes neutrophils. 301 98

Male Sprague-Dawley rats were subjected to a single, intratracheal instillation of 30 mg Min-U-Sil silica in sterile saline and were sacrificed 3, 7, or 14 days following instillation. Control animals were instilled with sterile saline only. Silica instillation produced an inflammatory reaction followed by histological changes characteristic of lung fibrosis. Thickened alveolar septa associated with inflammatory cells transforming into large multifocal fibrotic nodules were detected in silica-exposed animals. Increased numbers of bronchoalveolar cells (principally macrophages), elevated levels of protein (principally serum albumin), and lysozyme, proteolytic (trypsin-like), and myeloperoxidase activities were detected in lavage fluids obtained from animals instilled with silica. These factors (except for lysozyme activity) were elevated above control levels from 3 to 7 days postinstillation and declined to near control levels by Day 14. The rate of DNA, collagen, and noncollagen protein synthesis was significantly elevated in lung tissue minces from silica-treated rats 3 and 7 days after instillation. Elevated levels of total protein, and lung collagen in particular, were observed 9 weeks after insult. Lavage fluid from silica-instilled rats stimulates DNA synthesis in cultures of proliferating and quiescent rat lung fibroblasts. Lavage fluid from silica-instilled rats also stimulates lung fibroblasts to increase collagen and noncollagen protein synthesis.
...
PMID:Regulation of lung fibroblast proliferation and protein synthesis by bronchiolar lavage in experimental silicosis. 301 63


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>

---