Silver Nanoforms as a Therapeutic Agent for Killing Escherichia coli and Certain ESKAPE Pathogens.

The scope of this study included the preparation of silver nanoforms with high antimicrobial efficacy, low cost, and ease of application. The term 'silver nanoforms' refers to silver located on the amorphous or crystalline titanium dioxide (TiO2). Silver nanoforms may be used as an alternative to antibiotics in killing bacteria.

[Use of the materials based on partially reduced graphene-oxide with silver nanoparticle as bacteriostatic and bactericidal agent].

Background: Researches have been synthesizing nanocomposites with antibacterial properties for a dozen of years. A lot of study have confirmed a high antibacterial activity of silver nanoparticles and oxygraphene. Silica, titanium dioxide and hydroxyapatites of 1-100 nm are used as carrier for these composites.

Hydroxyapatites and europium(III) doped hydroxyapatites as a carrier of silver nanoparticles and their antimicrobial activity.

Hydroxyapatites (Ca10(PO4)6(OH)2 and Eu3+:Ca10(PO4)6(OH)2) were synthesized by aqueous synthesis route. Hydroxyapatites were impregnated with silver ions that were subsequently reduced. XRD, TEM, and SAED measurements were used in order to determine the crystal structure and morphology of the final products.

The role of complement activity in the sensitivity of Salmonella O48 strains with sialic acid-containing lipopolysaccharides to the bactericidal action of normal bovine serum.

Sialic acids are important constituents of animal tissue glycoconjugates and are also present in the antigens of some bacterial strains. Capsular polysaccharides with sialic acid (NeuAc) have been extensively studied with regard to sensitivity to the bactericidal action of serum, whereas little is known in this regard about lipopolysaccharides (LPS) which contain NeuAc. Strains of Salmonella O48, able to infect animals and containing the same structures of LPS with NeuAc, were examined for their susceptibility to the bactericidal action of normal bovine serum (NBS).

Proteomic analysis of serum of workers occupationally exposed to arsenic, cadmium, and lead for biomarker research: a preliminary study.

The main factor of environmental contamination is the presence of the heavy metals lead, cadmium, and arsenic. The aim of serum protein profile analysis of people chronically exposed to heavy metals is to find protein markers of early pathological changes. The study was conducted in a group of 389 healthy men working in copper foundry and 45 age-matched non-exposed healthy men.

Use of zwitterionic type of detergent in isolation of Escherichia coli O56 outer membrane proteins improves their two-dimensional electrophoresis (2-DE).

Escherichia coli O56 were originally isolated from infected humans. Here it is reported that using the zwitterionic detergent (Zwittergent Z 3-14) to isolate outer membrane proteins (OMPs) from Escherichia coli O56 is suitable for their separation by two-dimensional electrophoresis (2-DE) using pH 3-10 immobilized pH gradient IPG strips (BIO-RAD).

Sialic acid-containing lipopolysaccharides of Salmonella O48 strains--potential role in camouflage and susceptibility to the bactericidal effect of normal human serum.

Sialic acid (N-acetylneuraminic acid, NeuAc) plays an essential role in protecting gram-negative bacteria against the bactericidal activity of serum and may contribute to the pathogenicity of bacteria by mimicking epitopes that resemble host tissue components (molecular mimicry). The role of sialic acid (NeuAc)-containing lipopolysaccharides (LPS) of Salmonella O48 strains in the complement activation of normal human serum (NHS) was investigated. NeuAc-containing lipooligosaccharides cause a downregulation of complement activation and may serve to camouflage the bacterial surface from the immunological response of the host.

The occurrence, biodiversity and toxicity of Bacillus thuringiensis strains isolated from the insect pest Lymantria dispar (Poland).

The aim of this investigation was to survey the occurrence, biodiversity, and toxicity of Bacillus thuringiensis strains originating from dead caterpillars of the forest pest, Lymantria dispar (Lepidoptera). Morphological, biochemical, and microscopic identification of isolates from the insects showed the presence of five different Bacillus species, including 2% of B. thuringiensis.

Human complement activation by smooth and rough Proteus mirabilis lipopolysaccharides.

Introduction: Proteus mirabilis bacilli play an important role in human urinary tract infections, bacteremia, and rheumatoid arthritis. The authors previously studied human complement C3 conversion by smooth-form P. mirabilis O10, O23, O30, and O43 lipopolysaccharides (LPSs) and showed that smooth Proteus LPSs fragmented C3 in a dose- and time-dependent manner.

Killing of Gram-negative bacteria with normal human serum and normal bovine serum: use of lysozyme and complement proteins in the death of Salmonella strains O48.

Serum is an environment in which bacterial cells should not exist. The serum complement system provides innate defense against microbial infections. It consists of at least 35 proteins, mostly in pre-activated enzymatic forms.

Isolation of outer membrane proteins (OMP) from Salmonella cells using zwitterionic detergent and their separation by two-dimensional electrophoresis (2-DE).

We report that using the zwitterionic detergent Zwittergent Z 3-14 to isolate outer membrane proteins (OMPs) from Salmonella 048 is suitable for their separation by two-dimensional electrophoresis (2-DE) in a capillary tube system. Sample preparation is a very crucial step for any bacterial proteomic study. Some modifications were introduced to the 2-DE protocol suggested by O'Farrell and BioRad, which significantly impaired the resolution of proteins.

The interaction between Pseudomonas aeruginosa cells and cationic PC:Chol:DOTAP liposomal vesicles versus outer-membrane structure and envelope properties of bacterial cell.

The interactions between cationic liposomal formulations (PC:Chol:DOTAP 3:4:3) and 23 Pseudomonas aeruginosa strains were tested. The study was undertaken because different antimicrobial results had been obtained by the authors for Pseudomonas aeruginosa strains and liposomal antibiotics (Drulis-Kawa, Z., Gubernator, J.

[Infectivityand resistance to antibiotics of non-fermentative rods isolated from patients hospitalised in pediatric center of Lower Silesia in Wrocław in the years 2000-2006].

The aim of this study was to evaluate the frequency of isolation and antimicrobial resistance testing of non-fermentative rods isolated from clinical specimens from patients hospitalized in Korczak Pediatric Center of Lower Silesia in Wrocław. The susceptibility of bacteria to selected antibiotics was determined. The commonest pathogens were Pseudomonas rods (81.

[Infectivity and resistance to antibiotics of bacterial strains isolated from patients hospitalised in intensive care units].

The aim of this study was to evaluate the frequency of isolation and antimicrobial resistance testing of bacterial strains isolated from clinical specimens from patients hospitalized in three Intensive Care Units in Wrocław. The susceptibility of bacteria (107 strains) to selected antibiotics was determined. The results clearly show that non-fermentative rods were identified as the main agents causing pneumonia (58% of isolates).

The mechanisms of activation of normal human serum complement by Escherichia coli strains with K1 surface antigen.

Ten E. coli K1 strains isolated from the urine of children with urinary tract infections were sensitive to the bactericidal action of normal human serum (NHS). The role of the particular mechanisms of complement activation was determined in the process of killing these strains, showing variable sensitivity to the bactericidal action of NHS; three mechanisms of activation of human complement were observed.

Survival of Proteus mirabilis O3 (S1959), O9 and O18 strains in normal human serum (NHS) correlates with the diversity of their outer membrane proteins (OMPs).

Urinary tract infections are frequently caused by Proteus mirabilis strains. In the previous studies there were defined the complete structures of O-polysaccharide parts of lipopolysaccharides from strains: P. mirabilis O3 (S1959), P.

Bactericidal activity of normal bovine serum (NBS) directed against some Enterobacteriaceae with sialic acid-containing lipopolysaccharides (LPS) as a component of cell wall.

The sensitivity of bacteria to the bactericidal activity of serum depends on the structure and organization of the bacterial outer membrane. Sialic acid has been found in the O-specific region of bacterial lipopolysaccharide (LPS) and it plays an essential role in protecting Gram-negative bacteria against the bactericidal activity of human and animal serum. The susceptibility of Gram-negative bacilli with sialic acid-containing LPS to the bactericidal action of normal bovine serum (NBS) was determined.

A comparison of the in vitro antimicrobial activity of liposomes containing meropenem and gentamicin.

The antimicrobial activity of eight cationic, two neutral and three anionic liposome compositions containing meropenem and gentamicin was tested in vitro in broth and serum medium. The cationic formulations showed better antibacterial efficacy against both Gram-positive and Gram-negative bacteria than the anionic and neutral ones, regardless of the encapsulated drug. The most effective formulations were the cationic PC/DOPE/DOTAP 3:4:3 and PC/Chol/DOTAP 3:4:3, as the MICs with meropenem were 2 to 4 times lower than those of the free drug.

The susceptibility of anaerobic bacteria isolated from periodontal diseases to photodynamic inactivation with Fotolon (chlorin e6).

Photodynamic inactivation (PDI) may be a very promising alternative method for the antimicrobial treatment of periodontitis. Several studies have demonstrated the sensitivity of subgingival flora to PDI using toluidine blue, methylene blue, and chlorin e6 derivatives. In the present study we report the activity of the Fotolon sensitizer, composed of chlorin e6 and polyvinylpyrrolidone (PVP), against anaerobic bacteria isolated from periodontal diseases.

Differentiated pattern of protein composition of crystalline inclusions of newly isolated Bacillus thuringiensis strains from Silesia in Poland.

Protein profiles of crystal delta-endotoxins were determined in twenty nine Bacillus thuringiensis strains-soil and phylloplane isolates--from Poland. Electrophoretic analysis revealed quantatively and qualitatively different patterns of delta-endotoxin crystal preparations of these B. thuringiensis strains.

In vitro antimicrobial activity of liposomal meropenem against Pseudomonas aeruginosa strains.

Twelve lipid formulations of liposomal meropenem were tested on six drug-susceptible and two drug-resistant Pseudomonas aeruginosa strains to determine their antibacterial activity. Cationic liposomes, especially PC/DOPE/SA 4:4:2 and PC/DOTAP/Chol 5:2:3, were more effective than anionic ones against sensitive isolates as the MICs of those formulations were two to four times lower than those of the free drug. None of the studied liposomal forms of meropenem exhibited bactericidal activity against isolates, which are drug-resistant due to low permeability.

Potential possibilities of using phage typing in elimination of multidrug resistant staphylococci.

Coagulase-negative staphylococci (CoNS) have become the most often isolated bacteria from blood culture, spinal fluid and respiratory tracts of neonates. These nosocomial strains are often resistant to oxacillin and other antibiotics (macrolides, aminoglycosides and fluorochinolones). 50 multidrug resistant CoNS strains isolated from bloodstream neonatal infections were tested for sensitivity to 23 lytic staphylococcus bacteriophages.

[Bactericidal activity of normal human serum to gram-negative rods with sialic acid containing lipopolysaccharide].

The complement plays the most important role in eliminating bacterial invasion of the host, by facilitating phagocytosis of potential pathogens and by participating in the direct essential role in protecting gram-negative bacteria against bactericidal activity of serum. Sialic acids which are important constitutes of animal tissue glycoconjugates are also present in antigens of some bacterial strains. The susceptibility of gram-negative strains with sialic acid--containing lipopolysaccharides to bactericidal action sera was examined.

The factor C3 conversion in human complement by smooth Shigella flexneri lipopolysaccharides.

Shigella flexneri rods play an important role in human intestinal infections. In the presented studies we have shown that O-acetyl and glucose residues, substituted in main GalNAc-Rha chains of lipopolysaccharide (LPS) are important for the bactericidal effect of human serum. By dot-blot, immunoblotting and ELISA with immobilized LPS we have shown correlation of C3 fragments deposition and serum resistance.