muramidase and Sepsis

It was demonstrated for the first time that immobilized lysozyme can efficiently remove Escherichia coli and Pseudomonas aeruginosa lipopolysaccharides (endotoxins) from solutions. Experimentally confirmed sorption capacity for the developed sorbent was at least 400 ng of endotoxin per ml sorbent. The new sorbent is compatible with the whole human blood and can be potentially used in extracorporeal therapy in the treatment of sepsis.

Topics: Adsorption; Blood; Body Fluids; Enzymes, Immobilized; Humans; Lipopolysaccharides; Muramidase; Sepsis

To test the synergistic effect of Cpl-711 endolysin and antibiotics for antipneumococcal activity.. A combination of Cpl-711 and different antibiotics (amoxicillin, cefotaxime, levofloxacin and vancomycin) was tested in a checkerboard assay against several multidrug-resistant Streptococcus pneumoniae strains. Mouse and zebrafish models of pneumococcal sepsis were used to confirm the in vitro data.. The activity of Cpl-711 combined with amoxicillin or cefotaxime was synergistic in the bactericidal effect against a serotype 23F multiresistant clinical isolate of S. pneumoniae. Synergy between Cpl-711 and cefotaxime was validated using both mouse and zebrafish models.. Combination of Cpl-711 and cefotaxime may help in the treatment of diseases caused by multiresistant pneumococcal strains.

Topics: Animals; Anti-Bacterial Agents; Cefotaxime; Disease Models, Animal; Drug Resistance, Multiple, Bacterial; Drug Synergism; Female; Mice; Mice, Inbred BALB C; Muramidase; Pneumococcal Infections; Recombinant Fusion Proteins; Sepsis; Streptococcus Phages; Streptococcus pneumoniae; Zebrafish

Lysozyme, found in relatively high concentration in blood, saliva, tears, and milk, protects us from the ever-present danger of bacterial infection. Previous studies have reported proinflammatory responses of endothelial cells to the release of polyphosphate(PolyP). In this study, we examined the anti-inflammatory responses and mechanisms of lysozyme and its effects on PolyP-induced septic activities in human umbilical vein endothelial cells (HUVECs) and mice. The survival rates, septic biomarker levels, behavior of human neutrophils, and vascular permeability were determined in PolyP-activated HUVECs and mice. Lysozyme suppressed the PolyP-mediated vascular barrier permeability, upregulation of inflammatory biomarkers, adhesion/migration of leukocytes, and activation and/or production of nuclear factor-κB, tumor necrosis factor-α, and interleukin-6. Furthermore, lysozyme demonstrated protective effects on PolyP-mediated lethal death and the levels of the related septic biomarkers. Therefore, these results indicated the therapeutic potential of lysozyme on various systemic inflammatory diseases, such as sepsis or septic shock.

Topics: Animals; Anti-Inflammatory Agents; Cells, Cultured; Dose-Response Relationship, Drug; Endothelial Cells; Humans; Male; Mice; Mice, Inbred C57BL; Muramidase; Polyphosphates; Sepsis; Treatment Outcome; Umbilical Veins; Vasculitis

Acinetobacter baumannii, a Gram-negative multidrug-resistant (MDR) bacterium, is now recognized as one of the more common nosocomial pathogens. Because most clinical isolates are found to be multidrug resistant, alternative therapies need to be developed to control this pathogen. We constructed a bacteriophage genomic library based on prophages induced from 13 A. baumannii strains and screened it for genes encoding bacteriolytic activity. Using this approach, we identified 21 distinct lysins with different activities and sequence diversity that were capable of killing A. baumannii. The lysin (PlyF307) displaying the greatest activity was further characterized and was shown to efficiently kill (>5-log-unit decrease) all tested A. baumannii clinical isolates. Treatment with PlyF307 was able to significantly reduce planktonic and biofilm A. baumannii both in vitro and in vivo. Finally, PlyF307 rescued mice from lethal A. baumannii bacteremia and as such represents the first highly active therapeutic lysin specific for Gram-negative organisms in an array of native lysins found in Acinetobacter phage.

Topics: Acinetobacter baumannii; Acinetobacter Infections; Animals; Anti-Bacterial Agents; Bacteremia; Biofilms; Drug Resistance, Multiple, Bacterial; Female; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Microbial Sensitivity Tests; Muramidase; Sepsis

In septic shock (SS), dysfunction of many organ systems develops during the course of the illness, although the mechanisms are not clear. In earlier studies, we reported that lysozyme-c (Lzm-S), a protein that is released from leukocytes and macrophages, was a mediator of the myocardial depression and vasodilation that develop in a canine model of Pseudomonas aeruginosa SS. Whereas both of these effects of Lzm-S are dependent on its ability to intrinsically generate hydrogen peroxide, we subsequently showed that Lzm-S can also deposit within the vascular smooth muscle layer of the systemic arteries in this model. In the present study, we extend our previous findings. We used a canine carotid artery organ bath preparation to study the time course and dose dependence of Lzm-S deposition within the vascular smooth muscle layer. We used a human aortic vascular smooth muscle cell preparation to determine whether Lzm-S can persistently inhibit contraction in this preparation. We also used a canine P. aeruginosa model to determine whether Lzm-S deposition might occur in other organs such as the kidney, liver, and small intestine. The results showed that, in the carotid artery organ bath preparation, Lzm-S deposition occurred within minutes of instillation and there was a dose-response effect. In the human aortic vascular smooth muscle cell preparation, Lzm-S inhibited contraction during a 4-day period. In the in vivo model, Lzm-S accumulated in the kidney and the superior mesenteric artery. In a canine renal epithelial preparation, we further showed that Lzm-S can be taken up by the renal tubules to activate inflammatory pathways. We conclude that Lzm-S can deposit in the systemic vasculature and kidneys in SS, where this deposition could lead to acute organ dysfunction.

Topics: Animals; Aorta; Carotid Arteries; Cells, Cultured; Disease Models, Animal; Dogs; Humans; Intestine, Small; Kidney Tubules, Distal; Macrophages; Mesenteric Arteries; Muramidase; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Organ Culture Techniques; Pseudomonas aeruginosa; Pseudomonas Infections; Sepsis

Both highly specific antibodies and appropriate assay buffers are key elements in the development of sensitive multi-analyte diagnostic tests and essential assay components to minimize interferences from the sample matrix. Herein, we investigate the influence of 0.1 M Tris (pH 7.4)/0.1 M NaCl/10 mM CaCl(2)/0.1% Tween-20 used as assay buffer and diluent for serum, plasma and saliva samples in a protein biomarker chip for the diagnosis of sepsis. In detail, on-chip sandwich assays for detection of IL-6 and PCT are established using pure assay buffer and serum, plasma, and saliva, each diluted by a factor of 10 and 100 with assay buffer. The dilution linearity as well as the cross-reactivity to immobilized IL-8, IL-10 and TNF-α antibodies (<1.8% in plasma and serum) is investigated; furthermore the influence of immunoglobulin G, fibrinogen and lysozyme, highly abundant proteins in serum, plasma and saliva. This effect is two times more pronounced in serum than in plasma and saliva and strongly decreases with increasing analyte concentration. Though the matrix proteins bind unspecifically to the immobilized receptors, they do not prevent the analyte binding; on the contrary, the analyte is reliably detected with high sensitivity, featuring limits of detection of 16 ng/L and 0.31 μg/L, and coefficients of variation of 18% and 29% for IL-6 and PCT in 10% serum.

Topics: Antibodies; Biomarkers; Buffers; Cross Reactions; Diagnostic Tests, Routine; Fibrinogen; Humans; Immunoglobulin G; Indicator Dilution Techniques; Interleukins; Muramidase; Point-of-Care Systems; Protein Array Analysis; Saliva; Sepsis; Tumor Necrosis Factor-alpha

In septic shock, systemic vasodilation and myocardial depression contribute to the systemic hypotension observed. Both components can be attributed to the effects of mediators that are released as part of the inflammatory response. We previously found that lysozyme (Lzm-S), released from leukocytes, contributed to the myocardial depression that develops in a canine model of septic shock. Lzm-S binds to the endocardial endothelium, resulting in the production of nitric oxide (NO), which, in turn, activates the myocardial soluble guanylate cyclase (sGC) pathway. In the present study, we determined whether Lzm-S might also play a role in the systemic vasodilation that occurs in septic shock. In a phenylephrine-contracted canine carotid artery ring preparation, we found that both canine and human Lzm-S, at concentrations similar to those found in sepsis, produced vasorelaxation. This decrease in force could not be prevented by inhibitors of NO synthase, prostaglandin synthesis, or potassium channel inhibitors and was not dependent on the presence of the vascular endothelium. However, inhibitors of the sGC pathway prevented the vasodilatory activity of Lzm-S. In addition, Aspergillus niger catalase, which breaks down H(2)O(2), as well as hydroxyl radical scavengers, which included hydroquinone and mannitol, prevented the effect of Lzm-S. Electrochemical sensors corroborated that Lzm-S caused H(2)O(2) release from the carotid artery preparation. In conclusion, these results support the notion that when Lzm-S interacts with the arterial vasculature, this interaction results in the formation of H(2)O(2), which, in turn, activates the sGC pathway to cause relaxation. Lzm-S may contribute to the vasodilation that occurs in septic shock.

Topics: Aminoquinolines; Animals; Carotid Artery, Internal; Catalase; Cyclic GMP; Cyclic GMP-Dependent Protein Kinases; Cyclooxygenase Inhibitors; Dogs; Dose-Response Relationship, Drug; Enzyme Inhibitors; Ethanol; Free Radical Scavengers; Guanylate Cyclase; Humans; Hydrogen Peroxide; Hydroquinones; In Vitro Techniques; Indomethacin; Mannitol; Mesenteric Artery, Superior; Methylene Blue; Muramidase; Nitric Oxide; Nitric Oxide Synthase; omega-N-Methylarginine; Oxadiazoles; Phenylephrine; Prostaglandins; Protein Kinase Inhibitors; Quinoxalines; Receptors, Cytoplasmic and Nuclear; Sepsis; Signal Transduction; Soluble Guanylyl Cyclase; Thionucleotides; Time Factors; Vasoconstrictor Agents; Vasodilation

Extraintestinal pathogenic Escherichia coli (ExPEC) strains cause disease by invading normally sterile niches within the host body, e.g., urinary tract, blood and cerebrospinal fluid. Infections due to ExPEC strains, in particular urinary tract infections, cause considerable morbidity and significant health-care costs. The goal of our study is to evaluate whether Caenorhabditis elegans can be used as a model to study phenotypic and genetic virulence determinants of ExPEC strains. For this purpose, we used a collection of 31 E. coli strains isolated during acute extra-intestinal infections or from the feces of healthy individuals. For all strains, the phylogeny, the presence of ExPEC virulence factors, the resistance to biologically relevant stressors (bile, human serum and lysozyme), the motility, the growth rate, the virulence in C. elegans and in a murine septicaemia model has been established. The results show that there is a strong link between virulence in C. elegans and certain phenotypic and genetic virulence predictors of ExPEC strains determinable in vitro. Furthermore, there is a significant correlation between virulence of different ExPEC strains in C. elegans and in the murine model. Therefore, our results suggest that C. elegans can be used as a model to study virulence determinants of ExPEC strains.

Topics: Animals; Anti-Bacterial Agents; Bile; Caenorhabditis elegans; Escherichia coli; Escherichia coli Infections; Growth Inhibitors; Humans; Mice; Models, Animal; Movement; Muramidase; Sepsis; Serum; Survival Analysis; Virulence; Virulence Factors

We previously showed that lysozyme (Lzm-S), derived from leukocytes, caused myocardial depression in canine sepsis by binding to the endocardial endothelium to release nitric oxide (NO). NO then diffuses to adjacent myocytes to activate the cGMP pathway. In a canine right ventricular trabecular (RVT) preparation, Lzm-S also decreased the inotropic response to field stimulation (FSR) during which the sympathetic and parasympathetic nerves were simulated to measure the adrenergic response. In the present study, we determined whether the pathway by which Lzm-S decreased FSR was different from the pathway by which Lzm-S reduced steady-state (SS) contraction. Furthermore, we determined whether the decrease in FSR was due to a decrease in sympathetic stimulation or enhanced parasympathetic signaling. In the RVT preparation, we found that the inhibitory effect of Lzm-S on FSR was prevented by NO synthase (NOS) inhibitors. A cGMP inhibitor also blocked the depressant activity of Lzm-S. However, in contrast to the Lzm-S-induced decline in SS contraction, chemical removal of the endocardial endothelium by Triton X-100 to eliminate endothelial NO release did not prevent the decrease in FSR. An inhibitory G protein was involved in the effect of Lzm-S, since FSR could be restored by treatment with pertussis toxin. Atropine prevented the Lzm-S-induced decline in FSR, whereas beta(1)- and beta(2)-adrenoceptor function was not impaired by Lzm-S. These results indicate that the Lzm-S-induced decrease in FSR results from a nonendothelial release of NO. NO then acts through inhibitory G protein to enhance parasympathetic signaling.

Topics: Animals; Dogs; Electric Stimulation; Endothelium, Vascular; GTP-Binding Proteins; Muramidase; Myocarditis; Nitric Oxide; Receptors, Adrenergic, beta; Sepsis; Signal Transduction; Sympathetic Nervous System

Severe sepsis is associated with dysfunction of the macrophage/monocyte, an important cellular effector of the innate immune system. Previous investigations suggested that probiotic components effectively enhance effector cell functions of the immune system in vivo. In this study, we produced bacteria-free, lysozyme-modified probiotic components (LzMPC) by treating the probiotic bacteria, Lactobacillus sp., with lysozyme. We showed that oral delivery of LzMPC effectively protected rats against lethality from polymicrobial sepsis induced by cecal ligation and puncture. We found that orally administrated LzMPC was engulfed by cells such as macrophages in the liver after crossing the intestinal barrier. Moreover, LzMPC-induced protection was associated with an increase in bacterial clearance in the liver. In vitro, LzMPC up-regulated the expression of cathelicidin-related antimicrobial peptide (CRAMP) in macrophages and enhanced bactericidal activity of these cells. Furthermore, we demonstrated that surgical stress or cecal ligation and puncture caused a decrease in CRAMP expression in the liver, whereas enteral administration of LzMPC restored CRAMP gene expression in these animals. Using a neutralizing Ab, we showed that protection against sepsis by LzMPC treatment required endogenous CRAMP. In addition, macrophages from LzMPC-treated rats had an enhanced capacity of cytokine production in response to LPS or LzMPC stimulation. Together, our data suggest that the protective effect of LzMPC in sepsis is related to an enhanced cathelicidin-related innate immunity in macrophages. Therefore, LzMPC, a novel probiotic product, is a potent immunomodulator for macrophages and may be beneficial for the treatment of sepsis.

Topics: Animals; Antimicrobial Cationic Peptides; Cathelicidins; Gene Expression Regulation; Immunity, Innate; Immunologic Factors; Liver; Macrophages; Muramidase; Phagocytosis; Probiotics; Rats; Sepsis

Periods of stress are often associated with disease outbreaks in cultured fish, and stress is often characterized by the secretion of cortisol. Although stress and cortisol secretion are highly correlated in fish, the role of cortisol in affecting channel catfish (Ictalurus punctatus) pathogen susceptibility is unclear. The effects of short-term stress and exogenous cortisol administration on channel catfish susceptibility to Edwardsiella ictaluri, the etiologic agent of enteric septicemia of catfish (ESC), were investigated. Channel catfish were exposed to virulent E. ictaluri following a standardized 30-min low-water stress or administration of dietary cortisol (100 mg/kg feed) and compared to a pathogen-challenged control group of catfish. Pathogen susceptibility increased in stressed catfish (43.3% mortality) when compared to cortisol-fed catfish (26.7%) and controls (26.7%). A greater (P<0.05) percentage of stressed catfish (25.9%) tested positive for E. ictaluri relative to cortisol-fed catfish (13.0%) over the course of the study, however, average levels of circulating bacteria were not different (P>0.05) among the treatments. Catfish challenged by the low-water stress event had elevated (P<0.05) circulating levels of cortisol 1-day post-pathogen exposure and elevated (P<0.05) lysozyme activity 4 and 14 days post-pathogen exposure when compared to cortisol-fed and control-challenged catfish. Cortisol concentrations were not correlated (P>0.05) to either lysozyme activity or bacterial levels; however, lysozyme activity was positively correlated (P=0.0197) to blood bacterial concentrations. These results implicate other stress factors or pathways, separate from or possibly in conjunction with cortisol, in the stress-associated immunosuppression of channel catfish as it relates to ESC susceptibility.

Topics: Animals; Diet; Edwardsiella ictaluri; Enterobacteriaceae Infections; Fish Diseases; Hydrocortisone; Ictaluridae; Muramidase; Sepsis; Stress, Psychological

Inflammatory mediators have been implicated as a cause of reversible myocardial depression in septic shock. We previously reported that the release of lysozyme-c (Lmz-S) from leukocytes from the spleen or other organs contributes to myocardial dysfunction in Escherichia coli septic shock in dogs by binding to a cardiac membrane glycoprotein. However, the mechanism by which Lzm-S causes this depression has not been elucidated. In the present study, we tested the hypothesis that the binding of Lzm-S to a membrane glycoprotein causes myocardial depression by the formation of nitric oxide (NO). NO generation then activates soluble guanylyl cyclase and increases cyclic guanosine monophosphate (cGMP), which in turn triggers contractile impairment via activation of cGMP-dependent protein kinase (PKG). We examined these possibilities in a right ventricular trabecular preparation in which isometric contraction was used to measure cardiac contractility. We found that Lzm-S's depressant effect could be prevented by the non-specific NO synthase (NOS) inhibitor N(G)-monomethyl-l-arginine (l-NMMA). A guanylyl cyclase inhibitor (ODQ) and a PKG inhibitor (Rp-8-Br-cGMP) also attenuated Lzm-S's depressant effect as did chemical denudation of the endocardial endothelium (EE) with Triton X-100 (0.5%). In EE tissue, we further showed that Lzm-S caused NO release with use of 4,5 diaminofluorescein, a fluorescent dye that binds to NO. The present study shows that the binding of Lzm-S to EE generates NO, and that NO then activates the myocardial guanosine 3',5' monophosphate pathway leading to cardiac depression in sepsis.

Topics: Animals; Cell Membrane; Cyclic GMP; Dogs; Endocardium; Endothelium; In Vitro Techniques; Muramidase; Myocardial Contraction; Myocardium; Nitric Oxide; omega-N-Methylarginine; Oxadiazoles; Quinoxalines; Sepsis

The loss of spleen may increase the incidence of overwhelming sepsis. To prevent this, splenic autotransplantation has been performed in humans and experimental animals. However, there is still controversy about the effectiveness of regenerated splenic tissue in preventing infection. This study explored the effectiveness of splenic tissue autotransplantation in restoring host defense.. Rabbits were divided into three groups: splenic autotransplantation, sham operation, and total splenectomy. Histomorphology, T-lymphocyte count, serum lysozyme levels, hemolysin titers, and pneumococcal clearance were observed as read-out parameters over 24 weeks.. Histological study showed that the white pulp was poorly developed and central arterioles were missing in the regenerated splenic tissue of the autotransplanted rabbits. The weight of regenerated spleens recovered 6 months later in the splenic autotransplantation group was 11% of that in the sham operation group and was significantly less than the weight at implantation. There was no significant difference in the number of T lymphocytes or level of serum lysozyme between the three groups. A poor antibody response by the rabbits in the splenic autotransplantation and total splenectomy groups was noted after the primary intravenous administration of sheep red blood cells compared to those of sham operation group. After the challenge with type 3 pneumococci intravenously, pneumococcal clearance from the bloodstream in the splenic autotransplantation group did not differ significantly from that in the total splenectomy group, but was markedly delayed compared with that in the sham operation group.. The low quantity and poor quality of the regenerated splenic tissue contribute to the inferior immunoprotective ability of animals autotransplanted with one-third of the original spleen. This suggests that the regenerated spleen cannot compensate for the immunological function of the original one, especially host resistance to infection.

Topics: Animals; Disease Models, Animal; Immunity; Immunohistochemistry; Lymphocyte Count; Muramidase; Organ Transplantation; Pneumococcal Infections; Rabbits; Random Allocation; Reference Values; Regeneration; Sensitivity and Specificity; Sepsis; Spleen; Splenectomy; Survival Rate; Transplantation, Autologous; Treatment Outcome

To determine whether lactoferrin (LF) and lysozyme (LZ) can be used as immunohistochemical postmortem markers of sepsis, pulmonary tissue sections from autopsy cases of sepsis-related fatalities (n = 13) and control cases of non-septic fatalities (n = 14) were evaluated for differences in leucocytic immunoreactivity. LF and LZ were investigated in paraffin sections using the AEC technique. The immunohistochemical expression of both markers was scored, evaluating the quantity of immunopositive cells and the intensity of the intracellular immunoreactivity. There was a statistically significant association between an enhanced expression of LF on pulmonary leucocytes in sepsis-related fatalities in contrast to non-sepsis cases (P < 0.001), whereas no such difference could be observed for LZ immunoreactivity between the two study groups. Pneumonic tissue alterations had no significant influence on LF and LZ immunoreactivity, thus suggesting differences between the degranulation of these non-specific antibacterial agents in local and systemic inflammatory processes. While the variability of LZ immunoreactivity, possibly reflecting a non-specific release from lysosomes according to the length of the postmortem interval, limits its application to the postmortem diagnosis of sepsis, the immunohistochemical detection of an enhanced expression of LF can contribute to the postmortem discrimination between sepsis and non-septic fatalities.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Biomarkers; Cause of Death; Child; Child, Preschool; Female; Humans; Immunoenzyme Techniques; Lactoferrin; Leukocytes; Lung; Male; Middle Aged; Muramidase; Sepsis

Legionella pneumophila infection of guinea-pigs by the aerosol route with either of two strains, one (serogroup I) giving an acute the other (serogroup 3) giving a protracted illness, induced a pyrexia and similar pneumonic lesions. With both strains there was a bacteraemia with early decreases in serum iron and zinc and increases in serum copper concentrations. Marked changes in other serum components were evident only in those animals which had protracted illness (serogroup 3-infected animals). These included transient increases in aminotransferase, creatine kinase and sorbitol dehydrogenase activities and triglyceride levels, together with gradual decreases in alkaline phosphatase and leucine aminopeptidase activities. Serum lysozyme activity and acute-phase protein synthesis increased, as did the ratio of phenylalanine to tyrosine. The findings confirm the relevance of the aerosol-infected guinea-pig model for the investigation of the disease processes and evaluation of therapeutic measures for use in man.

Topics: Acute-Phase Proteins; Animals; Blood Proteins; Body Temperature; Copper; Female; Guinea Pigs; Iron; Legionnaires' Disease; Lung; Muramidase; Phenylalanine; Sepsis; Tyrosine; Zinc

The course of meningococcal infection and nonspecific and specific immunity in children subjected to different regimens of pathogenetic therapy were studied. It was shown that the clinico-immunological indices were more favourable in children treated with lasix as a diuretic agent. Recovery with defects was observed in 6.8 per cent of the children of this group, while in patients subjected to routine treatment the respective value amounted to 14.6 per cent. The use of lasix in combination with penicillin increased the efficacy of penicillin therapy and shortened the recovery period by 8.4 +/- 0.2 days as compared to that of routine treatment. No unfavourable effect of elevated penicillin concentrations on the lysozyme activity, blood bactericidal characteristics and composition of immunoglobulins A, M and G in the children was recorded.

Topics: Adolescent; Blood Bactericidal Activity; Child; Child, Preschool; Drug Therapy, Combination; Furosemide; Humans; Immunoglobulins; Infant; Meningitis, Meningococcal; Meningococcal Infections; Muramidase; Penicillins; Sepsis; Syndrome

Lysozyme levels were determined in serum and umbilical cord blood of 352 newborns and prematures. Levels in premature babies were found to be significantly lower than those of matures at the first day of life. A correlation was seen between the serum lysozyme and the birth weight of 219 mature newborns. In 14 premature babies with clinical signs of sepsis the concentrations of serum lysozyme were particularly decreased in cases of septicemia caused by gram-negative organisms. Serum levels of lysozyme in cord blood were significantly lower in 38 newborns with predisposition to septicemia (above all premature rupture of membranes greater than 24 hr.) comparing with healthy infants. The decreased serum levels of lysozyme in newborns with septicemia and the remarkable susceptibility of infections in male newborns are discussed.

Topics: Birth Weight; Female; Fetal Blood; Fetal Membranes, Premature Rupture; Humans; Infant, Newborn; Infant, Newborn, Diseases; Infant, Premature; Male; Muramidase; Pregnancy; Sepsis; Sex Factors

Topics: Anti-Bacterial Agents; Antibody Formation; Complement System Proteins; Humans; Immunoglobulins; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Muramidase; Sepsis; Staphylococcal Infections

Plasma lysozyme was measured in turkeys with experimental fowl cholera produced by either of two serotypes of Pasteurella multocida. Lysozyme was not detected in preexposure plasma, whereas plasma sampled when turkeys were terminally bacteremic contained 7.0-7.5 microgram of lysozyme/ml. Plasma lysozyme was measured in turkeys inoculated intravenously with P. multocida lipopolysaccharide (LPS). Turkeys inoculated with 10 microgram of LPS produced plasma lysozyme detectable for 2 hr after inoculation; those inoculated with 500 microgram of LPS produced plasma lysozyme detectable for at least 6 hr after inoculation. Egg-white lysozyme, equivalent in concentration to the plasma lysozyme detected in bacteremic turkeys, was active upon young cultures of P. multocida and increased the degree of lysis of P. multocida cells treated with deoxycholate. Lysozyme, ethylenediaminetetraacetate, and deoxycholate in combination produced the highest degree of lysis of P. multocida cells.

Topics: Animals; Deoxycholic Acid; Edetic Acid; Lipopolysaccharides; Microbial Sensitivity Tests; Muramidase; Pasteurella; Sepsis; Turkeys

Serum levels of lysozyme were studied in 43 term and 36 premature newborns. Levels in premature babies were found to be significantly (p less than 0,001) lower than those of matures. Observation over two weeks revealed a rise of serum lysozyme in premature babies and a decline in mature newborns. The level seems to depend upon the turnover of neutrophile granulocytes. In 5 premature babies with clinical signs of sepsis the serum lysozyme concentrations were significantly (p less than 0,01) lower than those in healthy prematures. It is assumed that the activity of the intraneutrophilic lysozyme in patients with bacterial infections is reduced to as little as 50%. Urine controls for lysozyme in 43 newborns (mature and premature) did not show evidence of measurable lysozyme concentrations.

Topics: Age Factors; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases; Muramidase; Neutrophils; Sepsis

Glucan is a potent reticuloendothelial stimulant whose immunobiological activity is mediated, in part, by an increase in the number and function of macrophages. In studying the role of glucan as a mediator of antibacterial activity, we attempted to ascertain the ability of glucan to modify the mortality of mice with experimentally induced Gram-positive bacteremia, and to enhance antibacterial defenses in rats as denoted by serum lysozyme and phagocytic activity. After intravenous administration of glucan, serum lysozyme concentrations were increased approximately sevenfold over control concentrations. The increase in serum lysozyme appeared to parallel the glucan-induced increase in phagocytosis and induced hyperplasia of macrophages. Prior treatment of mice with glucan significantly enhanced their survival when they were challenged systemically with Staphylococcus aureus. These studies indicate that glucan confers an enhanced state of host defense against bacterial infections.

Topics: Animals; Bacteriolysis; Immunotherapy; Macrophages; Male; Muramidase; Phagocytosis; Polysaccharides; Rats; Sepsis; Staphylococcal Infections; Staphylococcus aureus

Gram-negative bacterial pneumonias have been increasingly important as nosocomial infections. The following model was developed to study the pathogenesis and evaluate therapy of such infections. Intranasal instillation of rats with a suspension of 5 x 10(6) Klebsiella pneumoniae caused bronchopneumonia with 24 h. Bacteria were isolated from the lungs in large numbers (greater than 10(5) colony-forming units [CFU] for at least 13 days after inoculation. Thereafter, the viable concentration decreased to about 10(3) CFU at 21 days but increased to 10(4) CFU at 25 days. Mortality rarely exceeded 25%. Plasma zinc concentration decreased, and plasma seromucoid, lysozyme, and alpha2-macrofetoprotein increased during respiratory K. pneumoniae infection in rats. There seemed to be a linear relationship between seromucoid concentration and the concentration of K. pneumoniae in the lung expressed in log10 units. Plasma zinc, alpha2-macrofetoprtoein, or lysozyme levels, however, did not change until the concentration of bacteria retrieved fron lungs exceeded 4 to 5 logs, Analysis of blood samples obtained serially from the orbital sinuses revealed that rats that succumbed to infection had significantly higher levels of seromucoid, alpha2-macrofetoprotein, and lysozyme and lower levels of plasma zinc than infected rats that survived. Progressive increases in seromucoid and particularly in lysozyme and alpha2-macrofetoprotein appeared to be predicative of death. It is postulated that the threshold effect observed for alpha2-macrofetoprotein and lysozyme reflect significant damage to lung tissue, and thus these two variables are good indexes of the severity of this infection. We propose that this model may be of value in elucidating the pathogenesis of respiratory K. pneumoniae as well as in assessing various models of therapy.

Topics: alpha-Fetoproteins; Animals; Klebsiella Infections; Klebsiella pneumoniae; Lung; Male; Muramidase; Orosomucoid; Rats; Sepsis; Spleen; Zinc

The possibilities of antibacterial therapy in the clinics of burn diseases has at present decreased because of increasing microflora resistance to antibiotics. This phenomenon is one of the most often causes of antibacterial drug side effects in burn patients. For control of infections complications in burn patients which are most often lethal it is necessary to use biologically active subtance, such as prodigiozan and lysozime in addition to the directed antibiotic therapy. The use of specific antitoxic antistaphylococcal drugs, such as antistaphylococcal plasma and antistaphylococcal gamma-globulin in combination with the antibiotics of the direct action provided effective control of infectious complications and sepsis of staphylococcal genesis in burn patients. Decamine proved to be effective along with the usual use of nystatin in cases with dysbacteriosis as a result of the antibiotic side effects. In the patients treated with decamine the sings of candidosis disappeared by the 5th--7th day. Therefore, for decreasing the side effects of antibiotics in the clinics of burn patients it is expedient to use antibiotics in combination with the biologically active and immune preparations which increases the efficacy of antibiotic therapy, impfoves the treatment results and decreases the antibiotic side effects.

Topics: Anti-Bacterial Agents; Burns; Drug Resistance, Microbial; Drug Synergism; Drug Therapy, Combination; gamma-Globulins; Humans; Immunization, Passive; Lipopolysaccharides; Muramidase; Polysaccharides, Bacterial; Sepsis; Serratia marcescens; Staphylococcus

The effect of subsequent cyclic administration of oleandomycin and tetracycline on the titer of the complement, the content of lysozyme, the bactericidal properties of the serum and the presence of the antibiotic specific antibodies in the blood serum found in the Hoigne reaction were studied on rabbits. It was found that the subsequent cyclic administration of the antibiotics to both the intact animals and the animals with experimental staphylococcal sepsis was accompanied by an increase in the titer of the complement only on the 7th day of administration of oleandomycin, the first antibiotic. The subsequent administration of tetracycline and especially discontinuation of the antibiotics use resulted in a significant, stable and prolonged decrease in the complement titer. The cyclic subsequent administration of oleandomycin and tetracycline for 7 days was accompanied by an increase in the lysozyme content and serum bactericidal properties. Changes in the factors of non-specific resistance under the effect of the subsequent cyclic administration of oleandomycin and tetracycline on both the intact animals and the animals with experimental staphylococcal sepsis were accompanied by an appearance, progressive increase and prolonged preservation in the serum of the antibiotic specific antibodies found in the Hoigne reaction. A possibility of producing specific antibodies simultaneously to the 2 antibiotics, i. e. oleandomycin and tetracycline in their administration in subsequent 7-day cycles was shown.

Topics: Animals; Blood Bactericidal Activity; Chinchilla; Complement System Proteins; Drug Combinations; Muramidase; Oleandomycin; Rabbits; Sepsis; Staphylococcal Infections; Tetracycline

A study was made of some nonspecific immunity indices in staphylococcus sepsis and gastroenterocolitis during the infectious process in young children. Results of these investigations pointed to the depression of bactericidal and lysozyme activity of the blood serum and of the immunoadherence reaction at the acute period of the disease, and to some increase at the phase of recovery. There was also found an elevation of the phagocytic activity (of the phagocytolysis percentage) at the acute phase of the staphylococcus sepsis and gastroenterocolitis Antistaphylococcus gamma-globulin produced a positive effect on the lysozyme and bactericidal activity of the blood sera and promoted an increase of the blood phagocytic activity in the sick children.

Topics: Blood Bactericidal Activity; Enterocolitis, Pseudomembranous; Gastroenteritis; Immune Adherence Reaction; Male; Muramidase; Phagocytosis; Sepsis; Staphylococcal Infections

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

Biological properties of 142 Proteus strains isolated from patients were studied. Sensitivity of Proteus to II antibiotics was tested. The isolates were resistant to most of the antibiotics. The highest number of the isolates was sensitive to ampicillin (77.1 minus or plus 7.16) and especially to carbenicillin (82.6 plus or minus 6.16). This provided the use of carbenicillin for the treatment of experimental septicemia in albino mice and wound processes in rabbits with Proteus complications. The high therapeutic effect of the antibiotic was shown in experiments with 210 albino mice and 44 rabbits. The therapeutic effect of carbenicillin increased when it was used in combination with prodigiozan and especially in combination with prodigiozan and lysozyme.

Topics: Animals; Carbenicillin; Drug Synergism; Drug Therapy, Combination; Injections, Intraperitoneal; Mice; Microbial Sensitivity Tests; Muramidase; Prodigiosin; Proteus; Proteus Infections; Rabbits; Sepsis; Time Factors

The effect of repeated cycles of tetracycline and oleandomycin administration on the complement titer, content of lysozyme and bactericidal properties of the serum in rabbits with experimental staphylococcal sepsis was studied. It was shown that the septic process induced by intravenous inoculation of staphylococci was accompanied by stimulation of the host nonspecific resistance. However, repeated inoculations of the animals resulted in exhaustion of the host protective forces and decreased non-specific resistance. The use of tetracycline in experimental staphylococcal sepsis was accompanied by an increase in the complement titer, lysozyme content and bactericidal properties of the serum after both the 1st and 2nd cycles of the drug administration. The use of oleaudomycin induced an increase in the contents of the complement, lysozyme and bactericidal properties of the serum at the background of staphylococcal sepsis only after the 1st cycle. The repeated cycle of oleandomycin administration was accompanied by a decrease in the above indices. Such conditions should be taken into account in choosing the antibiotic for treatment of septic cases especially when repeated cycles of the drug administration are used.

Topics: Animals; Blood Bactericidal Activity; Complement System Proteins; Depression, Chemical; Immunity; Injections, Intramuscular; Muramidase; Oleandomycin; Periodicity; Rabbits; Sepsis; Staphylococcal Infections; Stimulation, Chemical; Time Factors

Topics: Adult; Bacterial Infections; Biological Products; Complement System Proteins; Enterocolitis, Pseudomembranous; Female; Hepatitis A; Humans; Intestines; Leukocytes; Middle Aged; Muramidase; Prodigiosin; Sepsis; Staphylococcal Infections

Cell-wall-deficient (CWD) forms of bacteria are associated with certain cases of idiopathic septicemia. In this preliminary study of blood examined immediately after venipuncture, structures with a morphology characteristic of CWD forms were seen parasitizing the erythrocytes. These inclusions were usually circumferential, but in some cases they protruded from the red cells. The CWD forms were detected by staining with Gould's rhodamine-labeled muramidase, which reacted similarly to acridine orange but with greater specificity. A blocking test, employing unlabeled muramidase, indicated the specificity of the reaction between muramidase and the microbial substrate. Reaction of the forms with muramidase indicates their bacterial, rather than mycoplasmal, nature. Thus in vivo CWD forms have a detectable component of muramic acid, at least in certain cases. Sixty-eight individuals with a diagnosis of fever of unknown origin were tested, with 51 nondebilitated individuals serving as controls. More intraerythrocytic forms reacting with muramidase were found in the patients than in the controls. Nearly 40% of the cases had a relatively high incidence of erythrocyte parasitism. In some instances when freshly drawn blood was examined, the structures, which appear to be microbial, extended in rhizoid filaments from the erythrocytes.

Topics: Acridines; Bacillus megaterium; Bacteria; Blood Specimen Collection; Cell Wall; Diagnosis, Differential; Erythrocytes; Fever of Unknown Origin; Fluorescent Dyes; Humans; Microscopy, Fluorescence; Muramidase; Sepsis; Staining and Labeling

Topics: Adolescent; Adult; Aged; Bacterial Infections; Burns; Candidiasis; Child; Child, Preschool; Female; Humans; Infant; Kidney Transplantation; Leukocytes; Male; Middle Aged; Muramidase; Neutrophils; Periodicity; Peroxidases; Phagocytes; Phagocytosis; Sepsis; Transplantation, Homologous; Wound Infection

Topics: Abortion, Septic; Antitoxins; C-Reactive Protein; Clostridium Infections; Escherichia coli Infections; Female; gamma-Globulins; Humans; Muramidase; Peritonitis; Pregnancy; Sepsis; Staphylococcal Infections

Topics: Adolescent; Adult; Age Factors; Aged; Antibodies; Antineoplastic Agents; Blood Bactericidal Activity; Burns; Child; Complement System Proteins; Drug Resistance, Microbial; Escherichia coli Infections; Female; Humans; Immunity; Middle Aged; Muramidase; Parotitis; Phagocytosis; Pneumonia; Polysaccharides, Bacterial; Pseudomonas Infections; Sepsis; Serratia marcescens; Staphylococcal Infections; Stimulation, Chemical

Topics: Cerebrospinal Fluid Shunts; Coagulase; Humans; Muramidase; Sepsis; Staphylococcal Infections; Staphylococcus; Urinary Tract Infections; Wound Infection

Topics: Humans; Leukemia, Lymphoid; Leukemia, Myeloid; Leukocytes; Muramidase; Sepsis

Topics: Adrenal Cortex Hormones; Anti-Bacterial Agents; Cellulitis; Female; Humans; Immunotherapy; Muramidase; Pelvic Inflammatory Disease; Peritonitis; Pregnancy; Puerperal Infection; Sepsis; Sulfonamides; Uterine Diseases

Topics: Anti-Bacterial Agents; Antibiotics, Antitubercular; Child; Dermatologic Agents; Humans; Infant; Infections; Muramidase; Sepsis; Virus Diseases