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[The effect of Aerococcus viridans on the properties of salmonellae and staphylococci in vitro].

According to electron microscopy the repeated contacts of Aerococcus viridans 167 (industrial strain for the probiotic Aerobact production) with Salmonella typhimurium and Staphylococcus aureus caused the deep changes of cellular structure, down to bacteriolysis. Remaining viable pathogenic cells gave posterity with changed biochemical properties and virulence. S. typhimurium completely lost typical biochemical properties, its mobility and ability to be agglutinated by O-specific Salmonella serum reduced after the fifth joint passage. Sharp decrease of the leucotoxic and loss of the lethal and necrotic activity of the S. aureus toxin were observed. The latter was characterized by the smaller number of protein fractions in comparison with control series on electrophoregrams and densitograms. Pathogenic bacteria, playing a role in formation of the pathological intestinal microbiocenosis (S. typhimurium) and being hospital infections (S. aureus) acquired increased sensitivity to antibiotics. The carried out researches open some mechanisms of bactericidal and bacteriostatic action of A. viridans (group 12, Bergey, 1994) and their metabolic products, causing antagonistic effect during direct action on infectious microorganisms.

Animals↗

Disseminated gonococcal infections (DGI).

Neisseria gonorrhoeae infects superficial membranes of the eyes, oropharynx, genital tract, and rectum prior to dissemination. Gonococcal isolates cultured from patients with disseminated gonococcal infections (DGI) show resistance to serum bacteriolysis, are very sensitive to penicillin, and have characteristic growth requirements for certain amino acids. DGI is characterized by recurrent chills and fever, polyarthralgias and/or polyarthritis (with effusions), and skin lesions. The skin manifestations of DGI include vesicopustules, hemorrhagic bullae, and petechiae. These lesions are found over the juxta-articular areas of the hands (extensor surfaces) or the feet (dorsal aspects). Focal and disseminated gonococcal infections are now treated with several types of penicillin regimens, tetracycline, or spectinomycin.

Anti-Bacterial Agents↗

[Soft contactlenses in general practice (author's transl)].

In contrast to the hard lenses the soft lens has enough permeability for oxygen and water-soluble substances, whereas high molecular substances, bacteria and virus cannot penetrate the soft lenses, so long as their surfaces are intact. The two principal production methods, the spin cast method and the lathe-turned method are compared. The duration of wearing of the soft lens depends on the deposits of proteins from the tears on the surface of the lens and the desinfection method. The daily boiling of the lenses shortens their useful life, while chemical desinfection causes besides bacteriolysis, damage of the corneal cell protein. The new cleaners on the base of proteolytic plant enzymes promise good results. For the optical correction of astigmatism with more than 1 cyl, soft lenses with conic outer surface are used or combinations of a soft and a hard lens (Duosystem). The therapeutic use of soft lenses has as aim: protection of the cornea against mechanical irritation, release of pain, protracted administration output of medicaments. Further indications for use: aseptic corneal inflammation and corneal defects.

Astigmatism↗

[Evaluation of the immunological activity and safety of group B meningococcal vaccine prepared from a natural complex of specific polysaccharide and outer membrane proteins].

Immunological activity and safety of group B meningococcal vaccine prepared from a natural complex of specific polysaccharide and outer membrane proteins were under study. The immunological safety of the vaccine was evaluated by the absence of antibodies to denaturated and native DNA (d-DNA and n-DNA). As shown with the use of the enzyme immunoassay (EIA), the administration of the vaccine did not induce antibody formation to d-DNA and n-DNA during the observation period. The titer of bactericidal antibodies in the immune bacteriolysis assay (IBA) to the vaccine strain B:2b:P1.2 after immunization increased four-fold and greater in 80% of the vaccinated persons. The significant increase of bactericidal antibodies to heterologous strains B:2a:P1.2 and B:15:P1.7 was registered in 20-30% of the vaccinees, respectively. A month after the repeated vaccination an increase in specific IgG antibodies to the complex antigen was found to occur according to EIA results. The use of RIB made it possible to evaluate the preventive activity of group B meningococcal vaccine as a whole and to suppose that the vaccine induced mainly type-specific response.

Adult↗

Preparation of anti-idiotypic antibodies specific for anti-HEL and analysis of their functional mimicry.

OBJECTIVE: This study is to investigate the functional mimicry by using anti-idiotypic antibodies of enzymes. METHODS: Monoclonal anti-idiotypic antibodies against anti-HEL (hen egg-white lysozyme, HEL) antibodies were obtained by fusion of Sp2/0 myeloma cells with spleen cells of syngeneic mice immunized with monoclonal anti-HEL antibodies against HEL's different antigenic epitopes. Then bacteriolysis of the anti-idiotypic antibodies were observed. RESULTS: Eight hybridomas strains secreting anti-idiotypic antibodies were selected and characterized. It was shown that two of eight anti-idiotypic antibodies secreted by two hybridomas (1A10C9 and 2A11C1B3) could mimic HEL catalytic activity to lyse Micrococcus lysodeikticus and that the catalytic effect of mixed anti-idiotypic antibodies of 1A10C9 and 2A11C1B3 was stronger than that of one of them, but less than HEL. CONCLUSION: The results demonstrated that the anti-idiotypic antibodies that could mimic enzyme activity existed in the idiotype network during anti-enzymatic immune response.

Animals↗

A murein hydrolase is the specific target of bulgecin in Escherichia coli.

A deletion in the structural gene for the soluble lytic transglycosylase, the predominant murein hydrolase in the soluble fraction of Escherichia coli, has been constructed. The mutant grows normally but exhibits increased sensitivity toward mecillinam, a beta-lactam specific for penicillin-binding protein 2. In the presence of furazlocillin or other beta-lactams with a specificity for penicillin-binding protein 3 which normally cause filamentation, bulges were formed prior to rapid bacteriolysis. Similar morphological alterations are known to develop in wild type E. coli cells when furazlocillin is combined with bulgecin, an antibiotic of unusual glucosaminyl structure. It turned out that bulgecin specifically inhibits the Sl-transglycosylase in a noncompetitive manner. Since bulgecin shows some structural analogy to the murein subunits we postulate that the soluble lytic transglycosylase, in addition to its active site, has a recognition site for specific murein structures. The possibility of an allosteric modulation of the activity of the enzyme by changes in the structure of the murein sacculus is discussed.

Amdinocillin↗

[Evaluation of serum bactericidal activity by laser flow cytofluorometry].

A method for evaluation of serum bactericidal activity against S. aureus by laser flow cytofluorometry has been developed and proposed for clinical application. This method was used to study the overall bactericidal activity of donors' sera and to estimate the contribution of complement to the process of bacteriolysis.

Adolescent↗

Rational basis of modern therapy of bacterial meningitis. Review of the literature and our clinical experience of 122 pediatric cases.

In recent years the treatment of bacterial meningitis has been modified on the basis of a better understanding of its physiopathological mechanisms. It has been shown, for example, that the inflammatory reaction is the primary cause of brain damage in bacterial meningitis. Inflammation and consequent brain damage are greatest in the first hours of antibiotic treatment when rapid and massive bacteriolysis takes place. In effect, the bacterial components activate metabolic pathways and cellular elements leading to the release of inflammation mediators: cytokines (TNF, IL-I) neutrophil degranulation products, complement components and clotting factors. Initially these substances make the blood-fluid and blood-brain barriers permeable. The result is cerebral oedema, excessive fluid pressure, congestion of the cerebral blood vessels and finally endocranial hypertension, reduced cerebral flow, cerebral hypoxia and brain damage. This sequence of events can be stopped by a multifactorial therapy that is not only aetiological (antibiotic) but also treats the inflammation, oedema (Dexamethasone, Mannitol) and symptoms. In this study 129 patients with non-tubercular bacterial meningitis were treated as described. All patients were administered Ceftriaxone (100 mg/kg per diem) Dexamethasone (0.2-0.3 mg/kg/per diem), Mannitol, fluid restriction and--where necessary--intensive symptomatic therapy (against shock, convulsions, fever). Both the antibiotic and the corticosteroid were also administered intrathecally at the time of the first lumbar puncture at intake. Of these 129 patients, 7 died very soon after admission as they had arrived in a moribund condition. Duration of therapy was 3-6 days in 90% of these cases. There were no recurrences.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Opsonophagocidal activity in sera from infants and children immunized with Haemophilus influenzae type b conjugate vaccine (meningococcal protein conjugate).

Immunization with Haemophilus influenzae type b capsular polysaccharide (polyribosylribitol-phosphate [PRP]) has resulted in limited and variable antibody radioimmunoassay in infants younger than 2 years of age. Although an H influenzae type B vaccine has been in use for several years, it is not used now for the age group at greatest risk for disease. In an effort to enhance immunogenicity, PRP has been coupled to various carrier proteins and to an outer membrane protein complex (OMPC) from Neisseria meningitidis group B. The latter approach has yielded a vaccine that elicits a good antibody response after a single 15-micrograms dose of vaccine in infants as young as 2 months of age, as measured by radioimmunoassay and immune bacteriolysis. In this report we describe the results of a pilot study using this H influenzae type B conjugate vaccine, PedvaxHIB, in children from 2 months to 4 years of age. Three different vaccine lots were examined for consistency of response. Sera were measured for antibody levels by radioimmunoassay and for functional activity using an opsonophagocytic assay using human adult neutrophils. These assays correlated well and demonstrated the excellent immune response and biologic activity of sera from infants vaccinated with this unique H influenzae type B conjugate vaccine.

Antibodies, Bacterial↗

Production and partial characterization of monoclonal antibodies to Pasteurella haemolytica A1 capsular polysaccharide and lipopolysaccharide.

Hybridoma-derived monoclonal antibodies (MAB) against the cell surface antigens of Pasteurella haemolytica serotype 1 were obtained by the fusion of murine myeloma cells (P3 X 63 - Ag 8.653) with splenocytes of BALB/c mice immunized with crude logarithmic growth-phase culture supernatant. Initial screening was performed, using an ELISA, with the same bacterial growth culture supernatant as coating antigens. Further selection was done, using a panel of purified antigens--either capsular polysaccharide or lipopolysaccharide--as the coating antigen in an ELISA, and then performing a leukotoxin-neutralization assay. Two MAB, designated IIB-6 and H-2, reacted specifically with the capsular polysaccharide and the other 3, designated IVG-3, IH-3, and IIC-2, reacted with the lipopolysaccharide. One MAB, designated IH-6, did not react with leukotoxin, capsular polysaccharide, or lipopolysaccharide. The MAB to the capsular polysaccharide (IIB-6 and H-2) were characterized further; both antibodies belonged to the IgM class and were agglutinating. In addition, they promoted neutrophil-mediated opsonophagocytosis and complement-mediated immune bacteriolysis of P haemolytica serotype 1. Results from 3 studies indicated that the MAB IIB-6 and H-2 were specific only to the capsular polysaccharide of serotype 1 of P haemolytica. The MAB to the lipopolysaccharide (IVG-3, IH-3, and IIC-2) were of the IgG1, IgG3, and IgM classes, respectively and were not characterized further. The availability of a MAB identifying a serotype-specific, surface-exposed determinant on the capsule of P haemolytica serotype 1 should facilitate and expand studies concerning the role of the capsular material and lipopolysaccharide in the pathogenicity of P haemolytica infection in cattle.

Animals↗

[Immunocytochemistry of Clostridium novyi antigens. Electron microscopic research].

The dynamics of the synthesis, transfer and excretion of toxin in C. novyi, growing in a liquid culture medium, have been studied on the level of bacterial ultrastructure by means of immunoferritin techniques modified by the authors. As revealed in this study, the basic mechanism of toxin excretion is realized by the active transfer of toxin through the enveloping structures after its accumulation in the periplasmatic space. In ageing cultures toxin may also be released in the process of bacteriolysis with the degradation of bacterial structures.

Antibodies, Bacterial↗

Chemotaxonomy of selected species of the Actinobacillus-Haemophilus-Pasteurella group by means of gas chromatography, gas chromatography-mass spectrometry and bioenzymatic methods.

Instrumental analytical and bioenzymatic methods were used to differentiate between species of the Actinobacillus-Haemophilus-Pasteurella group. Long-chain fatty acids were analysed directly with gas chromatography (GC) without derivatization. GC of trifluoroacetylated whole-cell methanolysates was a rapid method for differentiation. Cellular sugars were more suitable for differentiation than fatty acids. D-Glycero-D-mannoheptose, the major localization of which was lipopolysaccharide, distinguished H. aphrophilus from A. actinomycetemcomitans, H. paraphrophilus, H. influenzae type b, P. haemolytica, P. multocida, and P. ureae. GC of single colonies, which is a new chemotaxonomic method, was preferable to GC of liquid-grown cells. Lysozyme-and EDTA-induced bacteriolysis and reduction of methylene blue by cellular hydrogenase served as additional criteria for differentiation.

Actinobacillus↗

[Ultrastructural characteristics of the natural heteromorphic growth of Clostridium septicum].

Periodic cultures of C. septicum strain No. 59, growing in Pope's broth, have been studied by means of transmission electron microscopy on ultrathin sections. During the lagphase of growth the inoculated bacilliary cells are sequentially converted into giant filamentous multinucleate forms. These changes, reflecting the reaction of phenotypical adaptation to new environmental conditions, are followed by the restoration of the initial phenotype via the fragmentation of the giant cells. At the same time heteromorphic growth becomes, also spontaneously, atypical in some of the multinucleate cells. This atypical heteromorphic growth results in pronounced degenerative changes leading to bacteriolysis and the death of microbial cells due to disturbances in the coordination of the formation of structural and functional complexes in these cells at the period of their phenotypical adaptation. Such pathology of microbial cells leads to elimination of individual cells with developmental defects, which is finally conducive to the sanitation of the population.

Clostridium↗

Recurrent meningococcal meningitis with absence of the sixth component of complement: an evaluation of underlying immunologic mechanisms.

A 51/2-year-old black girl with recurrent meningococcal meningitis and absence of the sixth component of complement (C6) is reported. To explore the pathogenesis of recurrent neisserial infections in C6 deficiency, a detailed analysis of her immune competence was conducted. Her serum had normal chemotactic, opsonic, alternative complement pathway, and specific antibody activity, but lacked complement-mediated bacteriolytic activity. In addition, her C6-deficient serum was indistinguishable from normal serum in a complement-dependent assay of phagocyte bactericidal activity. Absent bacteriolysis remains the only consistent defect associated with recurrent neisserial infections and absence of one of the late-acting complement components.

Blood Bactericidal Activity↗

Fowl cholera: cross-protection induced by Pasteurella multocida separated from infected turkey blood.

Crude liver homogenates from turkeys that died of fowl cholera produced by serotype 1 or 3 Pasteurella multocida induced cross-protection. Pasteurella multocida harvested from the blood of infected turkeys by a centrifugal technique were as immunogenic as the liver homogenates. Neither bacterial cell-free blood plasma nor washed P. multocida from infected turkeys induced significant cross-protection. Blood plasma containing P. multocida induced significant cross-protection. Pasteurella multocida grown in the turkey underwent bacteriolysis after thawing from a frozen state. Filtered lysates did not induce cross-protection when used as vaccines whereas unfiltered lysates did. Membrane filters impeded passage of immunogenic material.

Animals↗

The effect of methylmethacrylate on complement activity.

The effect of methylmethacrylate on the activity of the complement sequence has been investigated in vitro by standard hemolysis techniques. It was demonstrated that concentrations of methylmethacrylate monomer as low as .25% inhibit the reactions of the complement sequence by 50%. Methylmethacrylate concentrations of 2.5 to 5.0% abolished all complement activity. This effect is on the late-acting components of the complement sequence which are important for chemotaxis of polymorphonuclear leukocytes, immune adherence of bacteria to polymorphonuclear leukocytes, phagocytosos of bacteria by polymorphonuclear leukocytes, and bacteriolysis.

Bacteria↗

Protection against experimental pyelonephritis by antibodies to pili.

Bacterial pili have been shown to be an important virulence factor for urinary tract infections. In this report we relate the results of studies which evaluated the influence of antipili antibody on the susceptibility of rats to ascending pyelonephritis and on several antibody-mediated antibacterial mechanisms. Rats immunized with E. coli type 1 pili, and animals infected with E. coli developed antipili antibodies in their serum. Active or passive immunization of rats with pili protected the animals from ascending pyelonephritis. Antipili antibody did not mediate complement-dependent bacteriolysis, opsonophagocytosis or promote more rapid intravascular clearance of injected E. coli. Humoral immunity to pili did, however, effectively inhibit bacterial adherence to epithelial cells. These studies indicate that type 1 E. coli pili are immunogenic and that antipili antibodies afford protection from ascending pyelonephritis. They suggest further that a mechanism of protection is inhibition of bacterial adherence.

Animals↗

[Combination of BCG and lepromin in the treatment of leprosy].

An unusual principle has been observed: when obliged to reproduce in a new medium ill-adapted to their development, mycobacteria abandon their common mode of reproduction--transversal division--and adopt a mode of evolution that puts less of a strain on their vitality: the long evolutive cycle, first described in 1899. In an initial step, the mycobacilli used for seeding purposes undergo auto-bacteriolysis, creating a cyanophilous fundamental substance which is in fact a symplasm due to the ex-bacillary microgranules, a multitude of independent and mobile genes. These genes merge according to a new and simpler arrangement: thus are formed the slender cocci that take the place of the amorphous cyanophilous substance. These cocci, released in the culture, multiply and lengthen into bacilli which merge to form a new amorphous cyanophilous substance. This new amorphous cyanophilous substance, thanks to another rearrangement of its genes, then forms a "crust" which undergoes exfoliation and crumbles into alcohol-acid-fast (a.a.f.) bacilli. Coryneforms and a.a.f. bacilli (mycobacteria) constitute two distinct agents with different and even occasionally opposite pathogenicities, as can be observed in co-cultures of Coryneforms (Hansen's bacillus or bacillus Calmette-Guérin) and tubercle (Koch's) bacillus. In such co-cultures, the tubercle bacilli progressively lose their vitality and virulence while, inversely, the Coryneforms reinforce their pathogenicity. Co-cultures of BCG and lepromin thus constitute an association with a particular property and most likely an auto-vaccinating activity against leprosy which is the subject of on-going research.

BCG Vaccine↗