muramidase has been researched along with Hemolysis* in 72 studies
4 review(s) available for muramidase and Hemolysis
Article | Year |
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Transition cow: non-specific immune response.
Topics: Animals; Blood Bactericidal Activity; Cattle; Female; Hemolysis; Muramidase; Pregnancy; Pregnancy, Animal | 2003 |
Earthworm immune responses.
The knowledge of the immunity in annelids started with the use of earthworms as biomarkers indicating changes caused by environmental pollution. Defence strategies effectively protect earthworms against bacterial infections and parasitic invasion. A natural immunity formed by anatomical and chemical protective barriers prevents damage of the underlying tissues, body fluid losses, and microbial infections of the body cavity. The internal defence mechanisms of annelids involve phagocytosis, nodule formation and encapsulation, blood coagulation and wound repair, and antibacterial immune proteins. The antibacterial activity of coelomic fluid associated with lysozyme-like substances and inducible humoral molecules support haemocytic reactions in the annelid defence system. Topics: Animals; Antibody Formation; Antineoplastic Agents; Environmental Monitoring; Hemolysis; Immunity, Cellular; Muramidase; Oligochaeta; Transplantation, Heterologous | 1997 |
Studies of host responses during experimental gingivitis in humans. II. Changes in acute phase reactants, serum immunoglobulins and complement during the development of gingival inflammation.
Topics: alpha 1-Antitrypsin; Blood Proteins; C-Reactive Protein; Chemotaxis, Leukocyte; Complement C4; Complement C5; Complement System Proteins; Gingivitis; Hemolysis; Humans; Immunoglobulins; Male; Muramidase; Neutrophils; Transferrin | 1979 |
[Some properties of carrier strains of Listeria monocytogenes (author's transl)].
About 60 characteristics have been investigated in 7 hemolyzing and 12 nonhemolyzing strains of L. monocytogenes. From these investigations resulted inter alia that the organism grows well under strictly anaerobic conditions, esculin is split at 45 degrees C,NH3 is produced from peptone, but not from arginin, and H2S can be traced by sufficiently sensitive methods. All strains possess a lipase, muramidase, and deoxyribonuclease, the hemolytic ones only also a lecithinase. Besides, the hemolytic strains only dispose of experimental virulence and of a CAMP factor-like agent. The experimental animal of choice seems to be the conjunctivally infected guinea pig in which a generalized infection develops. Topics: Ammonia; Anaerobiosis; Arginine; Deoxyribonucleases; Esculin; Hemolysis; Hydrogen Sulfide; Lipase; Listeria monocytogenes; Muramidase; Peptones; Phospholipases; Temperature | 1975 |
68 other study(ies) available for muramidase and Hemolysis
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Combination therapy of biogenic C-dots and lysozyme for enhanced antibacterial and antibiofilm activity.
Nearly 80% of human chronic infections are caused due to bacterial biofilm formation. The increased resistance against the conventional antimicrobial agents makes it difficult to treat the biofilm-related infections. The antibiotics resistance developed by planktonic cells has also become a major threat for human. Therefore, we have attempted here to develop an effective alternative strategy to overcome the issues of antibiotics resistance of bacteria. Upon synthesis, biogenic C-dots were combined with lysozymes which were further encapsulated into chitosan nanocarrier to form C-dots carrier (CDC). The as-synthesized C-dots were found irregular shaped and the average size of C-dots and CDC were 8 ± 2 nm and 450 ± 50 nm, respectively. To ensure secure and targeted delivery of C-dots and lysozyme we have employed chitosan, a biodegradable and natural biopolymer, as a delivery system. The study of time-dependent bacterial growth and flow cytometry analysis demonstrated that CDC can exhibit a synergistic bactericidal activity against the antibiotics resistant recombinant E. coli cells. Further, we have shown that the CDC could be a potent agent for both prevention of biofilm formation and eradication of preformed biofilm. In addition, we have observed that our drug delivery system is hemocompatible in nature making it suitable for in vivo applications. Therefore, we believe that the combination therapy of C-dots and lysozyme may be used as an excellent antibacterial and antibiofilm strategy. Topics: Anti-Bacterial Agents; Bacteria; Biofilms; Carbon; Chitosan; Drug Carriers; Drug Resistance, Bacterial; Green Chemistry Technology; Hemolysis; Humans; Muramidase; Quantum Dots | 2021 |
Preparation and preliminary evaluation of bio-nanocomposites based on hydroxyapatites with antibacterial properties against anaerobic bacteria.
Hexagonal nanocrystalline powders of the non-doped Ca Topics: Adsorption; Animals; Bacteroidetes; Biocompatible Materials; Blood Sedimentation; Cattle; Cell Line, Tumor; Cell Survival; Europium; Hemolysis; Humans; Hydroxyapatites; Microbial Sensitivity Tests; Muramidase; Nanocomposites; Prevotella; Serum Albumin, Bovine; Silver | 2020 |
Coupling PEG-LZM polymer networks with polyphenols yields suturable biohydrogels for tissue patching.
Poor mechanical performances severely limit the application of hydrogels in vivo; for example, it is difficult to perform a very common suturing operation on hydrogels during surgery. There is a growing demand to improve the mechanical properties of hydrogels for broadening their clinical applications. Natural polyphenols can match the potential toughening sites in our previously reported PEG-lysozyme (LZM) hydrogel because polyphenols have unique structural units including a hydroxyl group and an aromatic ring that can interact with PEG via hydrogen bonding and form hydrophobic interactions with LZM. By utilizing polyphenols as noncovalent crosslinkers, the resultant PEG-LZM-polyphenol hydrogel presents super toughness and high elasticity in comparison to pristine PEG-LZM with no obvious changes in the initial shape, and it can even withstand the high pressure from sutures. At the same time, the mechanical properties could be widely adjusted by varying the polyphenol concentration. Interestingly, the PEG-LZM-polyphenol hydrogel has a higher water content than other polyphenol-toughened hydrogels, which may better meet the clinical needs for hydrogel materials. Besides, the introduction of polyphenols endows the hydrogel with improved antibacterial and anti-inflammatory abilities. Finally, the PEG-LZM-polyphenol (tannic acid) hydrogel was demonstrated to successfully patch a rabbit myocardial defect by suturing for 4 weeks and improve the wound healing and heart function recovery compared to autologous muscle patches. Topics: Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents; Cell Line; Erythrocytes; Escherichia coli; Female; Heart Injuries; Hemolysis; Humans; Hydrogels; Methicillin-Resistant Staphylococcus aureus; Muramidase; Polyethylene Glycols; Polyphenols; Rabbits; Rats, Sprague-Dawley; Tannins; Wound Healing | 2020 |
Isolation of probiotics and their effects on growth, antioxidant and non-specific immunity of sea cucumber Apostichopus japonicus.
Probiotics play vital roles in controlling diseases, enhancing specific and non-specific immunity and stimulating growth in the aquaculture industry. However, the effect of fermentation of feed by probiotics on the immune ability of sea cucumber has not been reported to date. Here, three candidate probiotic strains (Bacillus species) were isolated from the culture seawater and sediment of sea cucumber, and fishmeal and scallop mantle fermented by the candidate probiotic strains were used to feed sea cucumber. The results showed that the free amino acid and small peptide contents of the fishmeal and scallop mantle were significantly increased after fermentation for 72 h. However, the weight gain (WG) and specific growth rate (SGR) of sea cucumber showed no significant differences among the fermented fishmeal, fermented scallop mantle and control groups. Scallop mantle fermented by the three candidate probiotics could increase the coelomocyte number and respiratory burst activity. The immune-related enzymatic activity was increased after consuming the fermented fishmeal and scallop mantle, while the activity of antioxidant enzymes was reduced. The expression levels of immune- and antioxidant-related genes were changed after consuming the fermented fishmeal and scallop mantle. Taken together, our results suggest that probiotics could increase the immunocompetence of sea cucumber, and fermented scallop mantle might be a potential substitute for fishmeal during feed preparation. Our results lay a foundation for further understanding the relationship between probiotics and the non-specific immunity of sea cucumber. Topics: Animal Feed; Animals; Bacillus; Catalase; Diet; Fermentation; Fish Products; Hemolysis; Muramidase; Pectinidae; Probiotics; Pseudoalteromonas; Stichopus; Superoxide Dismutase | 2020 |
Modulation of immune response and protective efficacy of recombinant outer-membrane protein F (rOmpF) of Aeromonas hydrophila in Labeo rohita.
The outer-membrane proteins (OMPs) of Aeromonas hydrophila, an imperative fish pathogen accountable for massive economic losses to aquaculture industry, are found to be immunogenic and considered as potential vaccine candidates. In spite of development in the formulation of vaccine candidates against Aeromonas infection, no commercial preparation has been done so far; in addition, the molecular mechanisms of immunoprotection induced by various vaccine formulations in Indian major carp, Labeo rohita, are little known. The present study was undertaken to evaluate the modulation of immunity and expression of immune-related genes post-rOmpF (recombinant outer-membrane protein of A. hydrophila, a novel vaccine candidate) immunization and protective efficacy after A. hydrophila challenge. The rOmpF-immunized fish showed a variable expression of the immune-related genes, viz. toll-like receptor 22 (TLR), complement component 3 (C3), chemokine (CXCa), tumor necrosis factor-α (TNFα), interleukin 1β (IL-1β), manganese superoxide dismutase (MnSOD) and natural killer enhancing factor (NKEF) in the head kidney tissues, when compared to the control group at different time intervals post-vaccination. A significant increase in serum hemolysin titer, ceruloplasmin level and myeloperoxidase activity was observed on day 140 post immunization. Also, bacterial agglutination titer and antiprotease activity were significantly increased on day 42 post immunization. No significant change was observed in lysozyme activity. Challenge studies with live A. hydrophila on day 140 post-immunization of L. rohita significantly increased the relative percentage survival (∼44%) in the vaccinated group. The results suggest that the rOmpF could be used as a potential vaccine candidate to combat A. hydrophila infection in fish. Topics: Aeromonas hydrophila; Animals; Antibodies, Bacterial; Bacterial Outer Membrane Proteins; Bacterial Vaccines; Ceruloplasmin; Cyprinidae; Fish Diseases; Gram-Negative Bacterial Infections; Hemolysis; Muramidase; Peroxidase; Porins; Recombinant Proteins | 2018 |
Lead exposure reduces carotenoid-based coloration and constitutive immunity in wild mallards.
The ingestion of spent lead (Pb) from ammunition is a known cause of mortality in waterfowl, but little is known about sublethal effects produced by Pb poisoning on birds, especially in wild populations. The authors studied potential sublethal effects associated with Pb exposure in mallards (Anas platyrhynchos) from the Ebro delta (northeastern Spain) after a ban on Pb ammunition. They analyzed the relationships between blood Pb levels and oxidative stress, immune response, and carotenoid-based coloration, which are known to be influenced by oxidative stress. Levels of Pb were reduced by half from 6 yr to 9 yr after the ban. Lipid peroxidation was positively related to Pb levels in females. The δ-aminolevulinic acid dehydratase activity was suppressed by Pb exposure and negatively associated with the activity of antioxidant enzymes. Carotenoid levels were positively associated with blood Pb concentration in both sexes, and males with higher Pb levels presented a less intense coloration in legs and beak. Levels of Pb were positively related to hemolytic activity of circulating immune system components and negatively related to lysozyme levels. In summary, Pb exposure was associated in a gender-specific way with increased oxidative stress, consequences on color expression, and impaired constitutive immunity. In females, antioxidants seemed to be allocated mostly in reproduction rather than in self-maintenance, whereas males seemed to better maintain oxidative balance to the detriment of coloration. Environ Toxicol Chem 2016;35:1516-1525. © 2015 SETAC. Topics: Animals; Carotenoids; Ducks; Female; Glutathione; Glutathione Peroxidase; Hemolysis; Immune System; Lead; Lipid Peroxidation; Male; Muramidase; Oxidation-Reduction; Oxidative Stress; Pigmentation; Porphobilinogen Synthase; Spain; Spectrophotometry, Atomic; Superoxide Dismutase; Testosterone | 2016 |
Common measures of immune function vary with time of day and sampling protocol in five passerine species.
Ecological immunology is a rapidly growing field of study that focuses on understanding variation in immune systems across species and how this relates to species ecology and evolution. Newly developed field methods aimed at studying variation in immune function in a field setting have yielded many insights. Nonetheless, there continues to be much debate regarding the interpretation of field measures of immune function. There is substantial evidence to suggest that handling stress could introduce variation into measures of immune function, yet no study has examined the impacts of incremental changes in handling times under 30 min on immune measures. Nor has any study examined variation in immune function with time of day, though other physiological measures, including glucocorticoids known to impact immune function, vary with time of day. Here, I used observational field data to test the hypothesis that innate immune function varies with handling stress. Furthermore, I tested the hypothesis that innate immune function changes over the course of the day. I show that measures of innate immune function vary with (1) handling stress over short time periods typical of sample collection in the field, and (2) the time of day that an individual is sampled. I discuss these findings from an ecological perspective and suggest that the observed variation is not random, but is likely to have important adaptive functions. I end with a summary of the practical implications of these findings for field studies of ecological immunology. Topics: Adaptation, Physiological; Animals; Antibodies; Circadian Rhythm; Hemolysis; Immunity, Innate; Muramidase; Passeriformes; Species Specificity; Stress, Physiological | 2015 |
The sea urchin Paracentrotus lividus immunological response to chemical pollution exposure: The case of lindane.
In the marine environment organochlorine insecticides can be broadly detected in water, sediments, and biota. These pollutants may have major ecological consequences since they may affect marine organisms and endanger organismal growth, reproduction or survival. In this study we investigated the modification of some sea urchin immunological parameters in response to subchronic lindane (γ-HCH) exposure. Adult specimens of the sea urchin Paracentrotus lividus were exposed to two different concentrations (0.1 and 0.5 mg L(-1)) of lindane. After 24 and 48h of treatment, we examined the lindane influence on coelomocytes vitality and enumeration as well on some humoral parameters. Our results showed that the presence of the pesticide affected both cellular and humoral components of the immune system. In particular, P. lividus coelomocytes vitality did not change but a decrease of the total cell number and an increase of the red cells was recorded. Haemolytic and lysozyme-like activities as well as antibacterial activity on Vibrio alginolyticus of treated animals decreased. Sea urchin immunological competence modifications might represent a tool for monitoring disease susceptibility thus providing biological criteria for the implementation of water quality standards to protect marine organisms. Topics: Animals; Anti-Bacterial Agents; Cell Survival; Environmental Monitoring; Hemolysis; Hexachlorocyclohexane; Insecticides; Muramidase; Paracentrotus; Reproduction; Vibrio alginolyticus; Water Pollutants, Chemical | 2015 |
Stable self-assembled nanostructured hen egg white lysozyme exhibits strong anti-proliferative activity against breast cancer cells.
Chemotherapy side effects have long been a matter of great concern. Here we describe a structurally stable self-assembled nanostructured lysozyme (snLYZ) synthesized using a simple desolvation technique that exhibited anticancer activity, as well as excellent hemocompatibility. Field emission scanning electron microscopy; atomic force microscopy and dynamic particle size analyzer were used for analyzing the synthesized snLYZ. The analysis revealed spherical shape with an average size of 300 nm. Circular dichroism and tryptophan fluorescence spectroscopic analysis revealed its gross change in secondary as well as the tertiary level of the structure. snLYZ also demonstrated excellent structural as well as the functional stability of LYZ in a wide range of pH and temperature with a fair level of protection against proteinase K digestion. When applied to MCF-7 breast cancer cells, it exhibited approximately 95% cell death within 24h, involving a reactive oxygen species (ROS) based mechanism, and showed excellent hemocompatibility. Fluorescence microscopy imaging revealed distinct cellular internalization of snLYZ and the formation of cytoplasmic granules, which initiated a cell-killing process through membrane damage. In order to mimic targeted therapy, we tagged folic acid with snLYZ, which further enhanced cytotoxicity against MCF-7 cells. Therefore, this is the first report of its kind where we demonstrated the preparation of a highly stable self-assembled nanostructured lysozyme with a strong anti-proliferative activity against breast cancer cells. Topics: 3T3 Cells; Animals; Breast Neoplasms; Cell Line; Cell Line, Tumor; Cell Proliferation; Chickens; Circular Dichroism; Egg White; Enzyme Stability; Female; Hemolysis; Humans; Hydrogen-Ion Concentration; MCF-7 Cells; Mice; Microscopy, Atomic Force; Microscopy, Electron, Scanning; Microscopy, Fluorescence; Muramidase; Nanostructures; Reactive Oxygen Species; Spectrometry, Fluorescence; Temperature | 2015 |
Layer-by-Layer (LBL) Self-Assembled Biohybrid Nanomaterials for Efficient Antibacterial Applications.
Although antibiotics have been widely used in clinical applications to treat pathogenic infections at present, the problem of drug-resistance associated with abuse of antibiotics is becoming a potential threat to human beings. We report a biohybrid nanomaterial consisting of antibiotics, enzyme, polymers, hyaluronic acid (HA), and mesoporous silica nanoparticles (MSNs), which exhibits efficient in vitro and in vivo antibacterial activity with good biocompatibility and negligible hemolytic side effect. Herein, biocompatible layer-by-layer (LBL) coated MSNs are designed and crafted to release encapsulated antibiotics, e.g., amoxicillin (AMO), upon triggering with hyaluronidase, produced by various pathogenic Staphylococcus aureus (S. aureus). The LBL coating process comprises lysozyme (Lys), HA, and 1,2-ethanediamine (EDA)-modified polyglycerol methacrylate (PGMA). The Lys and cationic polymers provided multivalent interactions between MSN-Lys-HA-PGMA and bacterial membrane and accordingly immobilized the nanoparticles to facilitate the synergistic effect of these antibacterial agents. Loading process was characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and X-ray diffraction spectroscopy (XRD). The minimal inhibition concentration (MIC) of MSN-Lys-HA-PGMA treated to antibiotic resistant bacteria is much lower than that of isodose Lys and AMO. Especially, MSN-Lys-HA-PGMA exhibited good inhibition for pathogens in bacteria-infected wounds in vivo. Therefore, this type of new biohybrid nanomaterials showed great potential as novel antibacterial agents. Topics: Amoxicillin; Anti-Bacterial Agents; Biocompatible Materials; Cell Line; Cell Survival; Drug Carriers; Dynamic Light Scattering; Ethylenediamines; Hemolysis; Humans; Hyaluronic Acid; Microscopy, Fluorescence; Muramidase; Nanoparticles; Nanostructures; Polymers; Porosity; Silicon Dioxide; Staphylococcus aureus; Thermogravimetry | 2015 |
Enzyme-coated mesoporous silica nanoparticles as efficient antibacterial agents in vivo.
Despite the fact that pathogenic infections are widely treated by antibiotics in the clinic nowadays, the increasing risk of multidrug-resistance associated with abuse of antibiotics is becoming a major concern in global public health. The increased death toll caused by pathogenic bacterial infection calls for effective antibiotic alternatives. Lysozyme-coated mesoporous silica nanoparticles (MSNs⊂Lys) are reported as antibacterial agents that exhibit efficient antibacterial activity both in vitro and in vivo with low cytotoxicity and negligible hemolytic side effect. The Lys corona provides multivalent interaction between MSNs⊂Lys and bacterial walls and consequently raises the local concentration of Lys on the surface of cell walls, which promotes hydrolysis of peptidoglycans and increases membrane-perturbation abilities. The minimal inhibition concentration (MIC) of MSNs⊂Lys is fivefold lower than that of free Lys in vitro. The antibacterial efficacy of MSNs⊂Lys is evaluated in vivo by using an intestine-infected mouse model. Experimental results indicate that the number of bacteria surviving in the colon is three orders of magnitude lower than in the untreated group. These natural antibacterial enzyme-modified nanoparticles open up a new avenue for design and synthesis of next-generation antibacterial agents as alternatives to antibiotics. Topics: Animals; Anti-Bacterial Agents; Cell Line; Cell Survival; Enzymes, Immobilized; Escherichia coli; Escherichia coli Infections; Fluorescein-5-isothiocyanate; HEK293 Cells; Hemolysis; Humans; Intestines; Mice; Mice, Inbred BALB C; Microscopy, Confocal; Muramidase; Nanoparticles; Porosity; Silicon Dioxide | 2013 |
Mixed protein-DNA gel particles for DNA delivery: role of protein composition and preparation method on biocompatibility.
Mixtures of two cationic proteins were used to prepare protein-DNA gel particles, employing associative phase separation and interfacial diffusion (Morán et al., 2009a). By mixing the two proteins, we have obtained particles that displayed higher loading efficiency and loading capacity values than those obtained in single-protein systems. However, nothing is known about the adverse effects on haemocompatibility and cytotoxicity of these protein-DNA gel particles. Here, we examined the interaction of protein-DNA gel particles obtained by two different preparation methods, and their components, with red blood cells and established cells. From a haemolytic point of view, these protein-DNA gel particles were demonstrated to be promising long-term blood-contacting medical devices. Safety evaluation with the established cell lines revealed that, in comparison with proteins in solution, the cytotoxicity was reduced when administered in the protein-DNA systems. In comparison with large-sized particles, the cytotoxic responses of small-sized protein-DNA gel particles showed to be strongly dependent of both the protein composition and the cell line being the tumour cell line HeLa more sensitive to the deleterious effects of the mixed protein-based particles. The observed trends in haemolysis and cell viabilities were in agreement with the degree of complexation values obtained for the protein-DNA gel particles prepared by both preparation methods. Topics: Animals; Biological Transport; Cell Survival; DNA; Dose-Response Relationship, Drug; Erythrocytes; Fibroblasts; Gels; HeLa Cells; Hemolysis; Humans; Mice; Muramidase; NIH 3T3 Cells; Particle Size; Protamines; Time Factors; Transfection | 2013 |
Microbial environment affects innate immunity in two closely related earthworm species Eisenia andrei and Eisenia fetida.
Survival of earthworms in the environment depends on their ability to recognize and eliminate potential pathogens. This work is aimed to compare the innate defense mechanisms of two closely related earthworm species, Eisenia andrei and Eisenia fetida, that inhabit substantially different ecological niches. While E. andrei lives in a compost and manure, E. fetida can be found in the litter layer in forests. Therefore, the influence of environment-specific microbiota on the immune response of both species was followed. Firstly, a reliable method to discern between E. andrei and E. fetida based on species-specific primers for cytochrome c oxidase I (COI) and stringent PCR conditions was developed. Secondly, to analyze the immunological profile in both earthworm species, the activity and expression of lysozyme, pattern recognition protein CCF, and antimicrobial proteins with hemolytic function, fetidin and lysenins, have been assessed. Whereas, CCF and lysozyme showed only slight differences in the expression and activity, fetidin/lysenins expression as well as the hemolytic activity was considerably higher in E. andrei as compared to E. fetida. The expression of fetidin/lysenins in E. fetida was not affected upon the challenge with compost microbiota, suggesting more substantial changes in the regulation of the gene expression. Genomic DNA analyses revealed significantly higher level of fetidin/lysenins (determined using universal primer pairs) in E. andrei compared to E. fetida. It can be hypothesized that E. andrei colonizing compost as a new habitat acquired an evolutionary selection advantage resulting in a higher expression of antimicrobial proteins. Topics: Animals; Bacteria; Base Sequence; Cell Line, Tumor; Cytotoxicity, Immunologic; Ecosystem; Electron Transport Complex IV; Gene Expression; Hemolysis; Immunity, Innate; Manure; Mice; Molecular Sequence Data; Muramidase; Oligochaeta; Proteins; Reverse Transcriptase Polymerase Chain Reaction; Sequence Analysis, DNA; Sequence Homology, Nucleic Acid; Soil Microbiology; Species Specificity; Toxins, Biological | 2013 |
Characterization of a versatile organometallic pro-drug (CORM) for experimental CO based therapeutics.
The complex fac-[Mo(CO)(3)(histidinate)]Na has been reported to be an effective CO-Releasing Molecule in vivo, eliciting therapeutic effects in several animal models of disease. The CO releasing profile of this complex in different settings both in vitro and in vivo reveals that the compound can readily liberate all of its three CO equivalents under biological conditions. The compound has low toxicity and cytotoxicity and is not hemolytic. CO release is accompanied by a decrease in arterial blood pressure following administration in vivo. We studied its behavior in solution and upon the interaction with proteins. Reactive oxygen species (ROS) generation upon exposure to air and polyoxomolybdate formation in soaks with lysozyme crystals were observed as processes ensuing from the decomposition of the complex and the release of CO. Topics: Animals; Binding Sites; Carbon Monoxide; Cell Line; Cell Survival; Coordination Complexes; Crystallography, X-Ray; Hemodynamics; Hemoglobins; Hemolysis; Hep G2 Cells; Humans; Mice; Muramidase; Organometallic Compounds; Prodrugs; Protein Structure, Tertiary; Serum Albumin | 2013 |
Zinc effect on the sea urchin Paracentrotus lividus immunological competence.
Pollution by heavy metals has become one of the most important problems in marine coastal areas as a consequence of anthropogenic inputs. Among metal contaminants, zinc, being considered not very toxic, is sometimes released into the sea in appreciable quantities and its concentration is loosely regulated. In this work we analyzed the effects of a high zinc concentration on the sea urchin Paracentrotus lividus immune system. In particular, after 24 h of zinc treatment, we evaluated coelomocytes morphology and composition as well as the zinc influence on some humoral parameters such as hemolysis, lysozyme-like activity and antibacterial activity on Vibrio alginolyticus. Our results evidenced that the presence of zinc affected both cellular and acellular components of the sea urchin immune system. The P. lividus coelomocytes changed in morphology and number; moreover, the amebocytes changed from a petaloid to a filipodial-like shape and the red spherula cells increased in number. Among the considered humoral effectors lysozyme-like activity and antibacterial activity on V. alginolyticus decreased in short-term to zinc treatment. The modifications in the sea urchin immunological competence might give an early indication of disease susceptibility thus suggesting to consider the examined defence mechanisms as potential biological indicators of metal pollution. Topics: Animals; Anti-Bacterial Agents; Disease Susceptibility; Hemolysis; Immunocompetence; Muramidase; Sea Urchins; Stress, Physiological; Vibrio alginolyticus; Water Pollutants, Chemical; Zinc | 2012 |
Short fasting and refeeding in red porgy (Pagrus pagrus, Linnaeus 1758): response of some haematological, biochemical and non specific immune parameters.
A short fasting-refeeding experience was applied to specimens of red porgy, Pagrus pagrus (Teleostei, Sparidae) to assess its effects on some physiological parameters. Haematological (haematocrit), biochemical (serum cortisol and glucose) and immunological (lysozyme, haemolytic and haemagglutinating activities) parameters were measured. For this study, two fish groups were considered: one was fasted for 14 days and then refed to satiation during further 7 and 15 days (indicated as fasted/refed group), the other was fed throughout the study and was taken as a control group. Significantly lower values were recorded for the condition index, the hepato-somatic index and viscero-somatic index in the fasted/refed group compared to the fed one. Fasting did not affect significantly the examined parameters, except for cortisol; refeeding for 7 days induced a significant increase in the haemoagglutinating titre and the spontaneous haemolytic activity, but when refeeding was extended to 14 days haemagglutinating and haemolytic values remained lower than those measured in fed fish. Topics: Animals; Blood Glucose; Body Size; Body Weight; Fasting; Feeding Behavior; Hemagglutination; Hematocrit; Hemolysis; Hydrocortisone; Muramidase; Perciformes | 2012 |
Ultraviolet irradiation of diacetylenic liposomes as a strategy to improve size stability and to alter protein binding without cytotoxicity enhancement.
Membrane-modification effects, induced by ultraviolet (UV) irradiation in diacetylenic liposomes, were analyzed upon contact with cells, biological membranes, and proteins. Liposomes formulated with mixtures of unsaturated 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine and saturated 1,2-dimyristoyl-sn-glycero-3-phosphocholine, in a 1:1 molar ratio, were compared with those that were UV-irradiated and analyzed in several aspects. Membrane polymerization inherence on size stability was studied as well as its impact on mitochondrial and microsomal membrane peroxidation induction, hemolytic activity, and cell viability. Moreover, in order to gain insight about the possible irradiation effect on interfacial membrane properties, interaction with bovine serum albumin (BSA), lysozyme (Lyso), and apolipoprotein (apoA-I) was studied. Improved size stability was found for polymerized liposomes after a period of 30 days at 4°C. In addition, membrane irradiation had no marked effect on cell viability, hemolysis, or induction of microsomal and mitochondrial membrane peroxidation. Interfacial membrane characteristics were found to be altered after polymerization, since a differential protein binding for polymerized or nonpolymerized membranes was observed for BSA and Lyso, but not for apoA-I. The substantial contribution of this work is the finding that even when maintaining the same lipid composition, changes induced by UV irradiation are sufficient to increase size stability and establish differences in protein binding, in particular, reducing the amount of bound Lyso and BSA, without increasing formulation cytotoxicity. This work aimed at showing that the usage of diacetylenic lipids and UV modification of membrane interfacial properties should be strategies to be taken into consideration when designing new delivery systems. Topics: Animals; Apolipoprotein A-I; Cattle; Cell Line, Transformed; Cell Survival; Dimyristoylphosphatidylcholine; Diynes; Erythrocytes; Hemolysis; Lipid Bilayers; Lipid Peroxidation; Liposomes; Mice; Microscopy, Electron, Scanning; Muramidase; Particle Size; Phosphatidylcholines; Polymerization; Protein Binding; Serum Albumin; Ultraviolet Rays | 2011 |
The muramidase EtgA from enteropathogenic Escherichia coli is required for efficient type III secretion.
Enteropathogenic Escherichia coli (EPEC) is an important cause of infectious diarrhoea. It colonizes human intestinal epithelial cells by delivering effector proteins into the host cell cytoplasm via a type III secretion system (T3SS) encoded within the chromosomal locus of enterocyte effacement (LEE). The LEE pathogenicity island also encodes a lytic transglycosylase (LT) homologue named EtgA. In the present work we investigated the significance of EtgA function in type III secretion (T3S). Purified recombinant EtgA was found to have peptidoglycan lytic activity in vitro. Consistent with this function, signal peptide processing and bacterial cell fractionation revealed that EtgA is a periplasmic protein. EtgA possesses the conserved glutamate characteristic of the LT family, and we show here that it is essential for enzymic activity. Overproduction of EtgA in EPEC inhibits bacterial growth and induces cell lysis unless the predicted catalytic glutamate is mutated. An etgA mutant is attenuated for T3S, red blood cell haemolysis and EspA filamentation. BfpH, a plasmid-encoded putative LT, was not able to functionally replace EtgA. Overall, our results indicate that the muramidase activity of EtgA is not critical but makes a significant contribution to the efficiency of the T3S process. Topics: Bacteriolysis; Enteropathogenic Escherichia coli; Erythrocytes; Escherichia coli Proteins; Gene Expression; Gene Knockout Techniques; Hemolysis; Humans; Hydrolysis; Membrane Transport Proteins; Muramidase; Peptidoglycan; Periplasmic Proteins; Recombinant Proteins; Virulence; Virulence Factors | 2011 |
Improved antimicrobial activity of h-lysozyme (107-115) by rational Ala substitution.
The most challenging target in the design of new antimicrobial agents is the development of antibiotic resistance. Antimicrobial peptides are good candidates as lead compounds for the development of novel anti-infective drugs. Here we propose the sequential substitution of each Ala residue present in a lead peptide with known antimicrobial activity by specific amino acids, rationally chosen, that could enhance the activity of the resultant peptide. Taking the fragment 107-115 of the human lysozyme as lead, two-round screening by sequentially replacing both Ala residues (108 and 111) by distinct amino acids resulted in a novel peptide with 4- and 20-fold increased antimicrobial activity against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 29213, respectively. These results reinforce the strategy proposed, which, in combination with simple and easy screening tools, will contribute to the rapid development of new therapeutic peptides required by the market. Topics: Alanine; Anti-Infective Agents; Escherichia coli; Hemolysis; Humans; Microbial Sensitivity Tests; Muramidase; Peptides; Staphylococcus aureus; Structure-Activity Relationship | 2010 |
Effects of two oils and 16 pure polycyclic aromatic hydrocarbons on plasmatic immune parameters in the European sea bass, Dicentrarchus labrax (Linné).
The in vitro effects of polycyclic aromatic hydrocarbons (PAHs) on two plasmatic immune parameters, lysozyme concentration and haemolytic alternative complement activity, of the European sea bass, Dicentrarchus labrax, were tested using field (10(-7) and 10(-9) mg mL(-1)) and high concentrations (10(-3) and 10(-5) mg mL(-1)) observed during oil spills. Peripheral blood from 105 fish was collected, centrifuged at 1200 g, for 10 min, at 4 degrees C and three plasma pools, each of 35 fish, were constituted. Two oils (heavy fuel oil and light cycle oil) and 16 pure PAHs, selected on the basis of the American Environmental Protection Agency list (US EPA), were tested in vitro on the two humoral immune parameters. Only three pure PAHs (anthracene, chrysene and dibenz[a,h]anthracene) modulated lysozyme concentration. Acenaphthene, acenaphthylene, anthracene, benzo[a]anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, pyrene and light cycle oil modified the haemolytic alternative complement activity after 4h of incubation. This study investigates the direct effects of several PAHs on fish humoral immune functions and describes the haemolytic complement activity of fish as suitable biomarkers of oil pollution. Topics: Animals; Antibody Formation; Bass; Hemolysis; In Vitro Techniques; Muramidase; Petroleum; Polycyclic Aromatic Hydrocarbons; Water Pollutants, Chemical | 2009 |
Cross-linking induces non-haemolytic antigen-loss from transfused red blood cells: a potential role for rheumatoid factor.
Transfusion of cross-match incompatible blood can lead to haemolysis. However, in some cases, incompatible transfused red blood cells are bound by antibody and then converted to being negative for both the incompatible antigen and the direct antiglobulin test. Using a murine model of this phenomenon, we have recently reported that antibodies binding to multiple epitopes are required. Herein, we report that antibodies against one epitope can induce antigen-loss if an anti-immunoglobulin G (IgG) antibody is also present. These findings support a model of cross-linking being required, and raise the possibility that naturally occurring anti-IgG, such as rheumatoid factor, may contribute to antigen-loss. Topics: Animals; Antibodies, Anti-Idiotypic; Antibodies, Monoclonal; Antigen-Antibody Reactions; Antigens, Surface; Chickens; Cross-Linking Reagents; Epitopes; Erythrocyte Membrane; Erythrocyte Transfusion; Hemolysis; Immunoglobulin Fab Fragments; Immunoglobulin Fc Fragments; Mice; Mice, Inbred C57BL; Mice, Transgenic; Muramidase; Rheumatoid Factor | 2008 |
Oncorhyncin III: a potent antimicrobial peptide derived from the non-histone chromosomal protein H6 of rainbow trout, Oncorhynchus mykiss.
The partial N-terminal amino acid sequence of the antimicrobial peptide reported in the present paper has been submitted to the TrEMBL database under the accession number P83338. A 6.7 kDa antimicrobial peptide was isolated from trout skin secretions using acid extraction followed by cation-exchange chromatography, (t)C(18) solid-phase extraction, and C(18) reversed-phase HPLC. The molecular mass of this peptide, which is tentatively named oncorhyncin III, is 6671 Da, as determined by matrix-assisted laser-desorption ionization MS. N-terminal amino acid sequencing revealed that the first 13 residues of oncorhyncin III are identical with those of the non-histone chromosomal protein H6 from rainbow trout. Hence these data combined with the MS results indicate that oncorhyncin III is likely to be a cleavage product of the non-histone chromosomal protein H6 (residues 1-66) and that it probably contains two methylated residues or one double methylation. The purified peptide exhibits potent antibacterial activity against both Gram-positive and Gram-negative bacteria, with minimal inhibitory concentrations in the submicromolar range. The peptide is sensitive to NaCl, and displays no haemolytic activity towards trout erythrocytes at concentrations below 1 microM. Scanning electron microscopy revealed that oncorhyncin III does not cause direct disruption of bacterial cells. Reconstitution of the peptide in planar lipid bilayers strongly disturbs the membranes, but does not induce the formation of stable ion channels. Taken together, these results support the hypothesis that oncorhyncin III plays a role in mucosal innate host defence. Topics: Amino Acid Sequence; Animals; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Chromatography, High Pressure Liquid; Chromosomal Proteins, Non-Histone; Erythrocytes; Gram-Negative Bacteria; Gram-Positive Bacteria; Hemolysis; Ion Channels; Lipid Bilayers; Methylation; Microbial Sensitivity Tests; Molecular Sequence Data; Muramidase; Oncorhynchus mykiss; Sequence Homology, Amino Acid; Sodium Chloride; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization | 2003 |
Antibacterial activity in four marine crustacean decapods.
A search for antibacterial activity in different body-parts of Pandalus borealis (northern shrimp), Pagurus bernhardus (hermit crab), Hyas araneus (spider crab) and Paralithodes camtschatica (king crab) was conducted. Dried samples were extracted with 60% (v/v) acetonitrile, containing 0.1% (v/v) trifluoroacetic acid, and further extracted and concentrated on C18 cartridges. Eluates from the solid phase extraction were tested for antibacterial, lysozyme and haemolytic activity. Antibacterial activity against Escherichia coli, Vibrio anguillarum, Corynebacterium glutamicum and Staphylococcus aureus was detected in extracts from several tissues in all species tested, but mainly in the haemolymph and haemocyte extracts. V. anguillarum and C. glutamicum were generally the most sensitive micro-organisms. In P. borealis and P. bernhardus most of the active fractions were not affected by proteinase K treatment, while in H. araneus and P. camtschatica most fractions were sensitive to proteinase K treatment, indicating antibacterial factors of proteinaceous nature. In P. bernhardus the active fractions were generally heat labile, whereas in H. araneus the activities were resistant to heat. Differences between active extracts regarding hydrophobicity and sensitivity for heat and proteinase K treatment indicate that several compounds are responsible for the antibacterial activities detected. Lysozyme-like activity could be detected in some fractions and haemolytic activity against human red blood cells could be detected in haemolymph/haemocyte and exoskeleton extracts from all species tested. Topics: Animals; Anomura; Corynebacterium; Decapoda; Endopeptidase K; Escherichia coli; Hemocytes; Hemolymph; Hemolysis; Hot Temperature; Humans; Muramidase; Staphylococcus aureus; Vibrio | 2002 |
Fcgamma and complement receptors: expression, role and co-operation in mediating the oxidative burst and degranulation of neutrophils of Brazilian systemic lupus erythematosus patients.
We have investigated the individual role of FcgammaR and CR, as well as their cooperation, in mediating the oxidative burst and degranulation of neutrophils of Brazilian systemic lupus erythematosus (SLE) patients. Neutrophils were stimulated with the immune complexes (IC)-IgG or -F(ab')2, opsonized or not with normal or SLE human serum. The oxidative burst was decreased in neutrophils of active SLE patients compared to healthy controls when this response was mediated by FcgammaR and/or CR, while the degranulation was unaffected. The SLE hypocomplementemia did not affect the oxidative burst mediated only by CR. FcgammaRII and CR1 expression on neutrophils of active SLE patients was reduced, while the expression of FcgammaRIII and CR3 was unaffected. These results suggest that the different FcgammaR and CR may be involved or cooperate in different ways in the mediation of the oxidative burst and the degranulation. Moreover, the decreased oxidative burst of neutrophils of active SLE patients may not depend only on SLE hypocomplementemia for IC opsonization. These observations are directed at the understanding of how each of these immune system components (FcgammaR, CR and complement) influences the precise biological neutrophil responses both in physiological and pathological conditions. Since the Brazilian population comprises many races, these results are important because they are directed at a specific population of SLE patients. Topics: Brazil; Cell Degranulation; Female; Gene Expression; Hemolysis; Humans; Immunoglobulin G; Luminescent Measurements; Lupus Erythematosus, Systemic; Male; Muramidase; Neutrophils; Receptors, Complement; Receptors, IgG; Respiratory Burst | 2002 |
Humoral immune parameters of cultured Atlantic halibut (Hippoglossus hippoglossus L.).
Several humoral immune factors were studied in a group of cultured halibut (Hippoglossus hippoglossus L.). The serum protein and IgM concentration was comparable to levels seen in other teleost species. A strong antibody activity against TNP-BSA was observed but not against other antigens tested. Lysozyme and anti-protease activity was detected and showed variable heat sensitivity. Unlike the anti-protease activity, the lysozyme activity of the sera was not sensitive to storage at -20 degrees C. No spontaneous haemolytic activity was observed and the sera had no bactericidal effect on any of the bacterial strains tested. Iron binding capacity of the sera was high. Individual variation was considerable in all the factors tested. Topics: Animals; Antibody Formation; Aquaculture; Complement System Proteins; Flounder; Freezing; Hemolysis; Hot Temperature; Immunoglobulin M; Iron; Muramidase; Protease Inhibitors; Serum Albumin, Bovine; Vaccination | 2001 |
Effect of lysozyme or modified lysozyme fragments on DNA and RNA synthesis and membrane permeability of Escherichia coli.
Previously we have shown that chicken egg white lysozyme, an efficient bactericidal agent, affects both gram-positive and gram-negative bacteria independently of its muramidase activity. More recently we reported that the digestion of lysozyme by clostripain yielded a pentadecapeptide, IVSDGNGMNAWVAWR (amino acid 98-112 of chicken egg white lysozyme), with moderate bactericidal activity but without muramidase activity. On the basis of this amino acid sequence three polypeptides, in which asparagine 106 was replaced by arginine (IVSDGNGMRAWVAWR, RAWVAWR, RWVAWR), were synthesized which showed to be strongly bactericidal. To elucidate the mechanisms of action of lysozyme and of the modified antimicrobial polypeptides Escherichia coli strain ML-35p was used. It is an ideal organism to study the outer and the inner membrane permeabilization since it is cryptic for periplasmic beta-lactamase and cytoplasmic beta-galactosidase unless the outer or inner membrane becomes damaged. For the first time we present evidence that lysozyme inhibits DNA and RNA synthesis and in contrast to the present view is able to damage the outer membrane of Escherichia coli. Blockage of macromolecular synthesis, outer membrane damage and inner membrane permeabilization bring about bacterial death. Ultrastructural studies indicate that lysozyme does not affect bacterial morphology but impairs stability of the organism. The bactericidal polypeptides derived from lysozyme block at first the synthesis of DNA and RNA which is followed by an increase of the outer membrane permeabilization causing the bacterial death. Inner membrane permeabilization, caused by RAWVAWR and RWVAWR, follows after the blockage of macromolecular synthesis and outer membrane damage, indicating that inner membrane permeabilization is not the deadly event. Escherichia coli bacteria killed by the substituted bactericidal polypeptides appeared, by electron microscopy, with a condensed cytoplasm and undulated bacterial membrane. So the action of lysozyme and its derived peptides is not identical. Topics: Anti-Bacterial Agents; Cell Membrane Permeability; DNA; Escherichia coli; Hemolysis; Humans; Kinetics; Microscopy, Electron; Muramidase; Peptide Fragments; RNA; Transcription, Genetic | 2000 |
Humoral immune parameters in Atlantic cod (Gadus morhua L.) I. The effects of environmental temperature.
The effects of environmental temperature on certain humoral immune parameters in Atlantic cod (Gadus morhua L.) were studied. Serum samples were collected from captive cod, of wild origin, kept at different temperatures for 12 months. It was found that immunoglobulin and natural antibody levels increased with increasing temperature whereas the total serum protein concentration, anti-protease activity, iron concentration, unsaturated and total iron binding capacity decreased with increasing temperature. Haemolytic activity and percentage iron saturation also tended to decrease with increasing temperature although this was not statistically significant. Topics: Adaptation, Physiological; Animals; Antibody Formation; Atlantic Ocean; Blood Proteins; Ecosystem; Endopeptidases; Female; Fishes; Hemolysis; Immunoglobulin M; Iron; Male; Muramidase; Protease Inhibitors; Temperature | 1999 |
Humoral immune parameters in Atlantic cod (Gadus morhua L.) II. The effects of size and gender under different environmental conditions.
The effects of size and gender on several humoral immune parameters in cod were examined under different environmental conditions. Serum samples were collected from wild cod of different sizes. Two samplings were undertaken: In the spring in relatively cold waters off the north west coast of Iceland and in the fall in relatively warm waters off the west coast of Iceland. Most of the parameters increased with increasing cod size, except the haemolytic activity which decreased. Higher serum protein levels were seen in cod sampled in the fall than in the spring. In cod sampled in the spring there was an apparent difference between specimens < 75 cm in length and the larger specimens with respect to haemolytic activity and iron concentration. None of the parameters were influenced by the gender of the cod. Topics: Adaptation, Physiological; Age Factors; Animals; Antibodies; Antibody Formation; Atlantic Ocean; Blood Proteins; Body Constitution; Ecosystem; Endopeptidases; Female; Fishes; Hemolysis; Immunoglobulin M; Iron; Male; Muramidase; Protease Inhibitors; Seasons; Sex Factors; Temperature | 1999 |
A novel anti-inflammatory activity of lysozyme: modulation of serum complement activation.
Lysozyme is an ubiquitous enzyme found in most biological secretions and leukocytes. This study was aimed at investigating its interaction with other inflammatory mediators on mucosa surfaces, particularly the complement system. Lysozyme has been shown in our present study, to inhibit the haemolytic activity of serum complement in a dose-dependent fashion, when tested within the levels present in normal and inflamed breast-milk samples, and other mucosal secretions. This represents a new anti-inflammatory action of lysozyme in relation to the serum complement, and the exact mode of the interaction need further studies. Topics: Animals; Complement Activation; Complement Hemolytic Activity Assay; Erythrocytes; Female; Hemolysis; Humans; Immunity, Mucosal; In Vitro Techniques; Inflammation; Inflammation Mediators; Milk, Human; Muramidase; Sheep | 1998 |
Isolation of a contact-dependent haemolysin from Mycobacterium tuberculosis.
Contact-dependent haemolytic activity was observed with cells of Mycobacterium tuberculosis H(37)Rv and M. tuberculosis H(37)Ra, but not with those of M. bovis, M. bovis BCG and M. africanum. Culture filtrates of all these strains did not exhibit any haemolytic activity. M. tuberculosis H(37)Rv was subsequently used for the isolation of haemolysin. Haemolytic activity was retained in the cell debris even after sonication of the cells and treatment with Tween 80 and lysozyme. Solubilisation of haemolysin was possible only after the cell debris was washed with ethanol 70% and then treated with Tween 80 0.1%. The haemolysin thus obtained showed a micellar M(r) of >200000 by gel-filtration on Sephadex G-200 and a subunit M(r) of 66000 by SDS-PAGE. It was sensitive to trypsin but stable when heated at 60 degrees C for 10 min. Polyclonal serum raised in rabbits against the haemolysin neutralised the haemolytic activity. The N-terminal amino-acid sequence of the 66-kDa subunit of haemolysin showed identity with TB66, the 66-kDa secretory protein of M. tuberculosis, and 30% homology with the haemolysin A precursor of Vibrio cholerae. Phosphatidylglycerol inhibited lysis of sheep erythrocytes by the haemolysin and is probably the receptor for the haemolysin. Haemolysin not only lysed erythrocytes, but was also cytotoxic to human lung cells. It appears that, among the members of the M. tuberculosis complex, the cell-bound contact-dependent haemolysin/cytolysin is restricted to M. tuberculosis and it may be associated with the pathogenesis of M. tuberculosis. Topics: Amino Acid Sequence; Animals; Blotting, Western; Cell Line; Chromatography, Gel; Enzyme-Linked Immunosorbent Assay; Hemolysin Proteins; Hemolysis; Hot Temperature; Humans; Lung; Molecular Sequence Data; Molecular Weight; Muramidase; Mycobacterium tuberculosis; Polysorbates; Rabbits; Solubility; Sonication; Surface-Active Agents; Trypsin | 1997 |
Complement recruitment using bispecific diabodies.
We describe the engineering of antibody fragments produced in bacteria for recruitment of complement effector functions. From a phage display repertoire we isolated human antibody fragments directed against complement C1q, and linked these to lysozyme-specific antibody fragments, creating bispecific antibodies (diabodies). One diabody was able to recruit C1q, resulting in efficient lysis of lysozyme-coated sheep erythrocytes, and also induced rosette-formation of erythrocytes with human monocytes and phagocytosis after phorbol ester stimulation. These diabodies may have therapeutic applications requiring the activation of complement. Topics: Animals; Antibodies, Bispecific; Base Sequence; Biotechnology; Complement Activation; Complement C1q; Complement System Proteins; Erythrocytes; Hemolysis; Humans; In Vitro Techniques; Monocytes; Muramidase; Oligodeoxyribonucleotides; Protein Engineering | 1997 |
Biochemical characterization of x-ray contrast media.
Eleven ionic and nonionic contrast media were compared in parallel regarding their effects on various biochemical parameters in vitro. Partition coefficient, protein binding, release of histamine, hemolysis inhibition and complement activation were determined as well as inhibition of various enzymes. Additionally, incompatibilities between contrast media and intravascular drugs that often are coadministered were determined.. Partition coefficients were determined in the system n-butanol/water by spectrophotometry. Protein binding was measured by equilibrium dialysis. Histamine release from rat peritoneal mast cells was measured by radioassay. Hemolysis inhibition and complement activation was determined in beagle dog serum using antibody-coated sheep erythrocytes. The inhibition of enzyme systems was measured photometrically. Incompatibility with coadministered drugs was registered by appearance of precipitations.. Hydrophilicity as determined by partition coefficients was highest for iotrolan and lowest for iotetrol. Protein binding ranged from practically zero for most substances to 14% for ioxaglate. Histamine release was highest for diatrizoate (77% at 100 mg I/mL) and lowest for iodixanol (1%). Complement activation at 100 mg I/mL ranged from 0% (diatrizoate, iopamidol) to 77% (iopentol). The inhibition of the enzyme systems urokinase, streptokinase, collagenase, tissue plasminogen activator, and lysozyme was lowest for the nonionic dimers.. All compounds influenced the parameters tested. However, the degree of interaction was different. Although there was no significant correlation between hydrophilicity (partition coefficient) or osmolality and the tested parameters, nonionic dimers seemed to be superior to nonionic monomers. The reason might lie in reduced chemotoxicity of this class of contrast media. Topics: 1-Butanol; Animals; Biochemical Phenomena; Biochemistry; Butanols; Chemical Precipitation; Complement Activation; Contrast Media; Diatrizoate; Dogs; Drug Incompatibility; Enzyme Inhibitors; Erythrocytes; Female; Hemolysis; Histamine Release; Iodipamide; Iopamidol; Ioxaglic Acid; Male; Mast Cells; Matrix Metalloproteinase Inhibitors; Muramidase; Photometry; Protein Binding; Rats; Sheep; Spectrophotometry; Streptokinase; Tissue Plasminogen Activator; Triiodobenzoic Acids; Urokinase-Type Plasminogen Activator; Water | 1996 |
Cell-mediated haemolytic activity of haemolymph from the Colorado potato beetle (Leptinotarsa decemlineata Say.)
Haemolytic activity was identified in cell-free haemolymph from larval and imago stages of Leptinotarsa decemlineata. The haemolytically active fraction of the haemolymph was active against human, sheep, bull, toad and mouse erythrocytes. There was no haemolysis in the presence of 0.001 M EDTA and 0.5% glutathione. The titre of haemolytic activity did not increase after injury or vaccination of the larvae with Microccocus lysodeikticus. Haemolysin, a heat-labile protein was partially purified by ammonium sulphate precipitation, gel filtration, and ion-exchange separation. SDS PAGE, electrophoresis and immunoblotting showed that the active factor was a protein with a molecular weight of approximately 55 kD. It was not bactericidal for various micro-organisms but the antibacterial activity of the lysozyme increased in the presence of haemolysin only when M. lysodeikticus were used as target cells. Spherulocytes synthesized and released the haemolytic protein in vitro. The haemolytic activity increased in the presence of lipopolysaccharide from Escherichia coli and Ca++ ions. The physiological role of the haemolysin is as yet unknown. Topics: alpha-Amylases; Animals; Bacteriolysis; Cations, Divalent; Coleoptera; Edetic Acid; Erythrocyte Membrane; Glutathione; Hemolymph; Hemolysin Proteins; Hemolysis; Humans; Insect Proteins; Larva; Micrococcus; Molecular Weight; Muramidase; Phenylmethylsulfonyl Fluoride; Phospholipids; Plant Proteins; Protease Inhibitors; Solanum tuberosum; Trypsin Inhibitors | 1996 |
PCBs increase molecular-related activities (lysozyme, antibacterial, hemolysis, proteases) but inhibit macrophage-related functions (phagocytosis, wound healing) in earthworms.
Both humoral and cellular immunodefense responses of the earthworms, Eisenia fetida andrei, Eisenia hortensis, and Lumbricus terrestris, have been compared after exposure to the PCB Aroclor 1254. Responses mediated by free factors, detected by in vitro assays for lysozyme, hemolysis, and proteases, were increased in both Eisenia. Antibacterial activity directed against pathogenic bacteria was increased in E.f. andrei. The resistance of L. terrestris against non-pathogenic bacteria was decreased, confirming that the bacteria were treated by different systems according to their pathogenicity. Nonspecific cellular functions, including phagocytosis and those related to wound healing, decreased dramatically in all earthworms. Topics: Aeromonas hydrophila; Animals; Endopeptidases; Hemolysis; Lethal Dose 50; Macrophages; Muramidase; Oligochaeta; Phagocytosis; Polychlorinated Biphenyls; Wound Healing | 1995 |
Preclinical testing of iopromide. 1st communication: pharmacological evaluation.
Pharmacological and pharmacokinetic characteristics of the non-ionic monomeric X-ray contrast agent iopromide (Ultravist, CAS 73334-07-3) were evaluated in preclinical studies. The scope of investigations included in vitro tests such as the determination of protein binding, the inhibition of complement, lysozyme, urokinase, platelet aggregation, the release of histamine, the influence on thromboplastin time. In vivo studies included bleeding time in rat, neural tolerance after intracisternal injection or administration into the carotid artery. Pharmacokinetic studies were performed in rats and dogs. Iopromide could be shown to be well tolerated in all the tests and species. Its pharmacokinetics was in agreement with the characteristics of an extracellular contrast agent with rapid renal elimination. Topics: Animals; Bleeding Time; Complement Activation; Contrast Media; Dogs; Erythrocytes; Hemolysis; Histamine Release; Humans; In Vitro Techniques; Iohexol; Muramidase; Pain; Partial Thromboplastin Time; Platelet Aggregation; Rats; Rats, Sprague-Dawley; Rats, Wistar; Urokinase-Type Plasminogen Activator | 1994 |
[Experimental study of biological effects of wood dust].
Topics: Animals; Bronchoalveolar Lavage Fluid; Dust; Female; Hemolysis; L-Lactate Dehydrogenase; Macrophages; Male; Muramidase; Rabbits; Rats; Wood | 1988 |
Improved agar plate assays of bovine lysozyme and haemolytic complement activity.
Topics: Agar; Animals; Cattle; Colostrum; Complement System Proteins; Female; Hemolysis; Methods; Muramidase; Pregnancy | 1986 |
[Lysozyme in the serum and granulocyte lysates of patients with myocardial infarct].
Topics: Adult; Aged; Granulocytes; Hemolysis; Humans; Middle Aged; Muramidase; Myocardial Infarction | 1983 |
Immunomodulators--thymus factor X (TFX) and levamisole in immune reactions and inflammatory processes.
Comparative evaluation of immunotropic and inflammatory activity of thymus factor (TFX) and levamisole was performed. In numerous experimental systems it was shown that both preparations exert stimulatory effect on the course and intensity of the specific immune reactions. Many tests proved their stimulatory effect on the nonspecifically induced inflammatory processes. TFX as well as levamisole, beside their influence on the course of immune reactions, are also active in the differentiation of T lymphocytes. Differences and similarities in the effect of both evaluated compounds were examined in the in vivo and in vitro systems and it was observed that levamisole possesses the components of activity atypical for thymus hormones. Topics: Animals; Cathepsins; Graft vs Host Reaction; Guinea Pigs; Hemolysis; Immunity, Cellular; Inflammation; Levamisole; Mice; Mice, Inbred Strains; Muramidase; Phagocytosis; Rabbits; Rats; Rats, Inbred Strains; Thymus Extracts; Tuberculin Test | 1981 |
Studies of pyruvate-water isotope exchange catalysed by erythrocytes and proteins.
Erythrocyte suspensions in buffer made with 2H2O catalyse the exchange of pyruvate protons. This process can be easly observed by spin-echo proton magnetic resonance. The dominant exchange process is shown to be due to the formation of Schiff-base links between pyruvate and amino groups of haemoglobin. Other proteins with free alpha-amino groups also catalyse the exchange. The pH*-dependence of the exchange rate due to hen-egg-white-lysozyme reflects the dissociation of the alpha-amino group. Topics: Amino Acids; Catalysis; Deuterium; Erythrocytes; Hemoglobins; Hemolysis; Humans; Kinetics; Magnetic Resonance Spectroscopy; Muramidase; Proteins; Pyruvates; Structure-Activity Relationship; Water | 1981 |
Inhibition of the hemolytic activity of quartz by a chemically modified lysozyme.
Topics: Animals; Carbodiimides; Hemolysis; Kaolin; Muramidase; Quartz; Quaternary Ammonium Compounds; Sheep; Silicon Dioxide | 1976 |
Studies on the Treponema pallidum immobilizing activity in normal human serum. 2. Serum factors participating in the normal immobilization reaction.
The T. pallidum immobilization reaction to be achieved by unheated normal serum was found to be complement dependent and the results presented suggested that complement was activated via the classical pathway. Besides complement, an immobilizing antibody of the IgM class was necessary for the immobilization reaction to occur. Lysozyme exerted an enhancing effect on the normal serum immobilization reaction. Topics: Blood; Complement System Proteins; Hemolysis; Hot Temperature; Immunoglobulin G; Immunoglobulin M; Muramidase; Treponema Immobilization Test; Treponema pallidum | 1976 |
Studies on the Treponema pallidum immobilizing activity in normal human serum. 3. The kinetics of immobilization reaction of normal and immune sera.
The influence of immobilizing antibody, complement and lysozyme, on the T. pallidum immobilization reactions of normal and immune sera was studied. Lysozyme shortened the lag periods and increased the reaction rates of the reactions of normal and immune sera. At high concentrations of added lysozyme, variations in the concentrations of immobilizing antibody and complement, within a wide range, did not further influence the kinetics of the two reactions. Preincubation with lysozyme did not influence the treponemes in the following immune serum immobiliation reaction provided the lysozyme was removed before the addition of antibody and complement. Normal serum was found to immobilize T. pallidum more rapidly than immune serum. This was seen also if the reaction mixtures were almost identical, the only differences being the immobilizing IgM antibody involved in the normal and the IgG antibody involved in the immune serum reaction. Topics: Blood; Complement System Proteins; Hemolysis; Immune Sera; Immunoglobulin G; Immunoglobulin M; Muramidase; Time Factors; Treponema Immobilization Test; Treponema pallidum | 1976 |
[Separation of lysozyme from sera with complement or antibody activities (author's transl)].
A gel-filtration method for separating lysozyme from sera with haemolytic complement activity and/or antibody activity is described. It is shown that the gel-filtration has only a small effect, whereas bentonite absorption results in a known lost of haemolytic complement activity. Topics: Absorption; Animals; Antibodies, Bacterial; Bentonite; Chromatography, Gel; Complement System Proteins; Guinea Pigs; Hemolysis; Humans; Immune Sera; Muramidase; Syphilis | 1975 |
[Biological properties of plasma-negative staphylococci isolated from patients in surgical departments].
A study was made of 111 strains of plasma-negative spathylococci isolated from the blood, pleural fluid, urine, and exudate of the abdominal cavity of 30 patients. The studies were carried out by 18 criteria. A variety of biological properties and signs characteristic of pathogenic staphylococci (hemolytic activity, anaerobic splitting of mannite, the presence of phosphatase, lysozyme, protease, alpha-toxin, fibrinolysin) were noted. A high resistance to tetracycline and penicillin was found in the strains isolated from the blood and the pleural cavity. Topics: Animals; Ascitic Fluid; Bacteriophage Typing; Bacteriuria; Cross Infection; Erythrocytes; Fibrinolysin; Hemolysis; Humans; Mannitol; Muramidase; Penicillin Resistance; Penicillins; Phospholipases; Phosphoric Monoester Hydrolases; Pleural Effusion; Pyelonephritis; Rabbits; Sepsis; Staphylococcal Infections; Staphylococcus; Surgical Procedures, Operative; Tetracycline; Toxins, Biological | 1975 |
Toxicity of quartz and kaolin towards membranes: effect of lysozyme.
Topics: Animals; Egg White; Erythrocytes; Hemolysis; Kaolin; Muramidase; Quartz; Sheep; Silicon Dioxide | 1974 |
[Bacteriocinogenicity of staphylococci isolated from different sources].
Topics: Adolescent; Adult; Bacteriocins; Child; Coagulase; Fibrinolysin; Hemolysis; Humans; Middle Aged; Muramidase; Nose; Penicillin Resistance; Pharynx; Phospholipases; Skin; Staphylococcal Infections; Staphylococcus | 1974 |
Enumeration of fecal Clostridium perfringens spores in egg yolk-free tryptose-sulfite-cycloserine agar.
The Shahidi-Ferguson perfringens, tryptose-sulfite-cycloserine (TSC), and egg yolk-free TSC agars have been tested for their suitability to enumerate fecal spores of Clostridium perfringens. When these spores comprised at least 20% of the total anaerobe spores, equally accurate counts were obtained in the three media. With lower ratios of C. perfringens spores, the most accurate counts were obtained in egg yolk-free TSC agar. The median C. perfringens spore count of 60 normal fecal specimens was log 3.4/g. A nonmotile, sulfite- and nitrate-reducing Clostridium, not identifiable with any known clostridial species, was isolated from 14 out of 60 fecal specimans. It was not differentiated from C. perfringens in the nitrite motility test, but could be distinguished by its inability to liquefy gelatin. Topics: Agar; Anaerobiosis; Bacteriological Techniques; Cell Count; Clostridium; Clostridium perfringens; Culture Media; Cycloserine; Evaluation Studies as Topic; Feces; Gelatin; Hemolysis; Humans; Lactose; Muramidase; Nitrates; Nitrites; Phospholipases; Species Specificity; Spores, Bacterial; Sulfites | 1974 |
A factor in guinea-pig serum with accelerating effect on immune immobilization of Treponema pallidum (IAF). Isolation, purification and differentiation from the known haemolytic complement components and from lysozyme.
Topics: Animals; Blood Proteins; Blood Sedimentation; Chromatography, DEAE-Cellulose; Chromatography, Gel; Chromatography, Ion Exchange; Complement System Proteins; Electrophoresis, Polyacrylamide Gel; Guinea Pigs; Hemolysis; Molecular Weight; Muramidase; Serum Globulins; Solubility; Treponema Immobilization Test; Treponema pallidum; Ultrafiltration | 1974 |
[Kinetics of immune immobilization of Treponema pallidum (Nichols strain) (author's transl)].
Topics: Antibodies, Bacterial; Antibody Specificity; Cell Wall; Complement System Proteins; Diagnostic Errors; False Positive Reactions; Hemolysis; Humans; Immune Sera; Kinetics; Lipopolysaccharides; Lipoproteins; Muramidase; Syphilis; Treponema Immobilization Test; Treponema pallidum | 1974 |
[Diagnostic use of the lysozyme activity of staplyococci].
Topics: Coagulase; Culture Media; Hemolysis; Muramidase; Staphylococcus | 1973 |
[Immunological and enzyme chemical studies on the cell-wall structure of Treponema pallidum].
Topics: Animals; Antibodies; Binding Sites, Antibody; Cell Wall; Complement System Proteins; Erythrocytes; Guinea Pigs; Hemolysis; Immune Sera; Lipopolysaccharides; Lipoproteins; Muramidase; Peptidoglycan; Time Factors; Treponema pallidum; Trypsin | 1972 |
Molecular basis of gouty inflammation: interaction of monosodium urate crystals with lysosomes and liposomes.
Topics: Acid Phosphatase; Animals; Cholesterol; Chromates; Erythrocytes; Estradiol; Female; Glucuronidase; Gout; Hemolysis; Humans; Leukocytes; Liposomes; Liver; Lysosomes; Male; Muramidase; Rabbits; Silicon Dioxide; Sucrose; Sulfatases; Testosterone; Uric Acid | 1972 |
Antibody formation by spleen cells of immunologically tolerant mice stimulated with antigen-antibody complexes.
Topics: Animals; Antibody Formation; Antibody-Producing Cells; Antigen-Antibody Complex; Antigens; Coombs Test; Erythrocytes; Female; Hemagglutination Tests; Hemolysis; Immune Tolerance; Immunoglobulin G; Muramidase; Polysaccharides, Bacterial; Rabbits; Sheep; Spleen; Splenectomy; Streptococcus pneumoniae | 1971 |
Production of multivalent extracellular filtrates of Staphylococcus aureus.
Topics: Animals; Carbon Dioxide; Cell-Free System; Coagulase; Culture Media; Deoxyribonucleases; Dialysis; Egg Yolk; Erythrocytes; Esterases; Female; Filtration; Hemolysin Proteins; Hemolysis; Histocytochemistry; Horses; Humans; Lipase; Muramidase; Peptide Hydrolases; Phosphoric Monoester Hydrolases; Rabbits; Ribonucleases; Sheep; Staphylococcus; Time Factors | 1970 |
Experiemental and clinical studies on muramidase (lysozyme). I. Muramidase activity of normal human blood cells and inflammatory exudates.
Topics: Blood Platelets; Clinical Enzyme Tests; Erythrocytes; Exudates and Transudates; Hemolysis; Humans; Inflammation; Leukocytes; Lymphocytes; Monocytes; Muramidase; Skin Window Technique; Staphylococcal Infections | 1970 |
Lymphocyte stimulation by a glycopeptide isolated from Streptococcus pyogenes C203S. I. Isolation and partial purification.
Topics: Amino Acids; Animals; Antigens; Antigens, Bacterial; Bacillus subtilis; Chromatography, DEAE-Cellulose; Deoxyribonucleases; Erythrocytes; Glycopeptides; Glycoproteins; Hemolysis; Humans; Lymphocyte Activation; Molecular Weight; Muramidase; Pyrogens; Rabbits; Ribonucleases; Streptococcus pyogenes; Thymidine; Tritium; Uridine | 1970 |
[Simultaneous presence of hemagglutinins and lysozymes in plants and animals. Prokop's protectins].
Topics: Animals; Culture Media; Hemolysis; Lectins; Muramidase; Plant Extracts; Plant Lectins; Plants, Medicinal; Tissue Extracts | 1970 |
Hemolysin and lysozyme production by staphylococci isolated from bovine udders.
Topics: Animals; Bacteriolysis; Cattle; Coagulase; Female; Hemolysin Proteins; Hemolysis; Mammary Glands, Animal; Mastitis, Bovine; Milk; Muramidase; Staphylococcus | 1970 |
Interactions of the complement system with the surface and endotoxic lipopolysaccharide of Veillonella alcalescens.
Electron microscopic studies demonstrated that lesions were produced on the endotoxic lipopolysaccharide (LPS) as well as on the cell surface of V. alcalescens after reaction with fresh guinea pig serum. These lesions were approximately 90 A in diameter, and were seen on two characteristic structural entities derived from LPS preparations after incubation with serum. The use of numerous inhibitors, inactivators, and reaction conditions affecting hemolytic C' activity revealed that these lesions were mediated by the C' system. Concomitant with lesion formation, C' was fixed; the effect on classical C'3 activity was pronounced. It is concluded that endotoxic LPS, as contained in the outer three-layered membrane of the bacterial cell, is a substrate for the C' enzymes. It is suggested that certain biological activities of endotoxin may derive from its effects on the C' system. Topics: Aluminum Silicates; Complement Fixation Tests; Complement System Proteins; Endotoxins; gamma-Globulins; Hemolysis; Immune Sera; Lipopolysaccharides; Microscopy, Electron; Muramidase; Polysaccharides, Bacterial; Veillonella | 1967 |
Complement and lysozyme requirements for spirochetolysis in guinea pig serum.
During experiments on the immunological immobilization of treponemes, several cultured strains were lysed in the guinea pig serum used as a source of complement. In further studies employing Borrelia vincentii, lysis, observed by darkfield, appeared as swelling and some beading of the cells. Complete disruption eventuated. Untreated guinea pig serum was strongly lytic, whereas little or no lysis occurred in bentonite-adsorbed samples. Activity was restored to these samples by adding commercially obtained crystalline egg-white lysozyme. Serum samples which had been heated, absorbed with aggregates of human gamma-globulin, or treated with ethylenediaminetetraacetate to remove, or inactivate, complement also lost spirochetolytic activity. Topics: Absorption; Animals; Bacteriolysis; Borrelia; Complement System Proteins; Edetic Acid; gamma-Globulins; Guinea Pigs; Hemolysis; Hot Temperature; Humans; Muramidase; Syphilis; Treponema Immobilization Test; Treponema pallidum | 1967 |
[Hemagglutination test for the demonstration of lysozyme].
Topics: Animals; Erythrocytes; Hemagglutination Inhibition Tests; Hemagglutination Tests; Hemolysis; Hydrogen-Ion Concentration; Muramidase; Sheep; Surface-Active Agents | 1966 |
ATTEMPTS TO ISOLATE C'3 ACTIVITY FROM PIG SERUM.
Topics: Animals; Chemical Precipitation; Chemistry Techniques, Analytical; Climate; Complement System Proteins; Edetic Acid; Formaldehyde; Hemolysis; Immune System Phenomena; Muramidase; Research; Sulfonic Acids; Swine; Zymosan | 1965 |
ANTISERUM TO LEUCOCYTE LYSOSOMES. ITS CYTOTOXIC, GRANULOLYTIC, AND HEMOLYTIC ACTIVITIES.
Antisera to rabbit polymorph granules and to rabbit erythrocytes have been prepared in guinea pigs. Both antigranule and antierythrocyte sera are hemolytic and both exhibit striking cytotoxicity on leucocytes. The sequence of toxic events, as observed by phase contrast cinemicrophotography and electron microscopy, consists of explosive granule lysis, cell swelling, cytoplasmic liquifaction, and nuclear fusion. Other rabbit cells are also susceptible to these cytotoxic effects, but cells, including polymorphs, of other mammals are not. Cytotoxic action of the antisera requires, in addition to the antibody, heat-labile serum factors and divalent cations, suggesting that the action is a combined one of antibody and complement. The morphologic observations have been supported by biochemical studies demonstrating release into the medium of granule-bound hydrolases following exposure of polymorphs or of isolated granules to the antigranule or antierythrocyte sera. Granulolytic activity of the antisera can be reduced or removed by absorption with either rabbit leucocyte granules or with erythrocytes, indicating that leucocyte granules and erythrocytes have an identical or similar membrane constituent. The observations lend support to the notion that lysosomal hydrolases may exert autolytic effects in some situations. Topics: Animals; Antibodies; Cathepsins; Cytoplasm; Cytoplasmic Granules; Erythrocytes; Guinea Pigs; Hemolysis; Hydrolases; Immune Sera; Leukocytes; Lysosomes; Microscopy, Electron; Muramidase; Neutrophils; Rabbits; Research; Sulfatases; Toxicology | 1964 |
A COMPARISON OF THE ANTIBACTERIAL ACTIVITY OF HUMAN SERUM AND OXALATED PLASMA ON STRAINS OF ESCHERICHIA COLI AND AEROBACTER AEROGENES.
Topics: Anti-Bacterial Agents; Bacteriological Techniques; Blood; Calcium; Complement System Proteins; Enterobacter aerogenes; Escherichia coli; Hemagglutination; Hemagglutination Tests; Hemolysis; Humans; Microbiology; Muramidase; Oxalates; Pharmacology; Plasma; Research | 1964 |
COMPARISON OF BACTERICIDAL AND HEMOLYTIC SERUM SYSTEMS. II. ANALYSIS OF INHIBITORS IN NORMAL SERUM FRACTIONS.
Topics: Beta-Globulins; Blood Protein Electrophoresis; Blood Proteins; Complement System Proteins; Escherichia coli; gamma-Globulins; Hemolysis; Muramidase; Pharmacology; Research | 1964 |
Interaction between "liquoid" (sodiumpolyanetholsulphonate) and lysozyme in the immune haemolytic reaction.
Topics: Anti-Infective Agents, Local; Antibody Formation; Dermatologic Agents; Hemolysis; Muramidase; Polyanetholesulfonate | 1963 |
Agglutination and lysis of erythrocytes by lysozyme.
Topics: Agglutination; Cell Death; Erythrocytes; Hemagglutination; Hemagglutination Tests; Hemolysis; Muramidase | 1958 |