Characterization of viable but nonculturable state of .

is an opportunistic bacterial pathogen linked with a range of human diseases. The objective of this study was to investigate the viable but nonculturable (VBNC) state of the bacterium. To induce the VBNC state, cells were maintained in sterilized phosphate-buffered saline at 4°C for three weeks.

Biofilm Formation in : The Role of the Gene.

is a bacterium that inhabits human oral cavities and is an emerging intestinal tract pathogen known to be a biofilm producer and one of the bacterial species found in dental plaque. In this study, biofilms of oral and intestinal isolates were phenotypically characterized. The role of the gene, which is linked to the regulation of biofilm formation in other pathogens, was assessed in relation to the pathogenic potential of this bacterium.

The effect of trisodium phosphate crosslinking on the diffusion kinetics of caffeine from chitosan networks.

This work examines the relationship between microstructural properties of hot-moulded chitosan networks, crosslinked with trisodium phosphate, and diffusive behaviour from these networks. Analysis through infrared spectroscopy (FTIR) confirmed successful crosslinking of the polymer chains and bioactive entrapment, while X-ray diffraction (WAXD) and dynamic oscillation in-shear elucidated the higher order structural properties of each matrix, as they transitioned from solutions to amorphous gels to semi-crystalline matrices. The picture of molecular motion observed in these systems and consequent application of the Flory-Rehner theory further indicated that different extents of chitosan crosslinking yielded a distinct water infusion functionality seen in the levels of swelling.

Pomegranate Peel Extract Is a Potential Alternative Therapeutic for Giardiasis.

Giardiasis is a major diarrheal disease affecting approximately 2.5 million children annually in developing countries. Several studies have reported the resistance of () to multiple drugs.

Manipulation of the Glass Transition Properties of a High-Solid System Made of Acrylic Acid-N,N'-Methylenebisacrylamide Copolymer Grafted on Hydroxypropyl Methyl Cellulose.

Crosslinking of hydroxypropyl methyl cellulose (HPMC) and acrylic acid (AAc) was carried out at various compositions to develop a high-solid matrix with variable glass transition properties. The matrix was synthesized by the copolymerisation of two monomers, AAc and N,N'-methylenebisacrylamide (MBA) and their grafting onto HMPC. Potassium persulfate (KSO) was used to initiate the free radical polymerization reaction and tetramethylethylenediamine (TEMED) to accelerate radical polymerisation.

Genetic characterisation of Campylobacter concisus: Strategies for improved genomospecies discrimination.

Although at least two genetically distinct groups, or genomospecies, have been well documented for Campylobacter concisus, no phenotype has yet been identified for their differentiation and thus formal description as separate species. C. concisus has been isolated from a variety of sites in the human body, including saliva and stool samples from both healthy and diarrhoeic individuals.

High frequency acoustic nebulization for pulmonary delivery of antibiotic alternatives against Staphylococcus aureus.

The increasing prevalence of multidrug resistant bacteria has warranted the search for new antimicrobial agents as existing antibiotics lose their potency. Among these, bacteriophage therapy, as well as the administration of specific bacteriolysis agents, i.e.

Investigation of cytotoxicity of negative control peptides versus bioactive peptides on skin cancer and normal cells: a comparative study.

Background: Resonant recognition model-myxoma virus (RRM-MV), a bioactive peptide analogue for myxoma virus MV-T5 protein, was computationally designed by the RRM. In this study, the anticancer effects of RRM-MV were assessed in vitro against four negative control peptides on human skin cancer and normal cells.

Results & Discussion: The effects of RRM-MV versus negative control peptides on cells were evaluated by quantitative and qualitative assays.

A bioactive peptide analogue for myxoma virus protein with a targeted cytotoxicity for human skin cancer in vitro.

Background: Cancer is an international health problem, and the search for effective treatments is still in progress. Peptide therapy is focused on the development of short peptides with strong tumoricidal activity and low toxicity. In this study, we investigated the efficacy of a myxoma virus peptide analogue (RRM-MV) as a candidate for skin cancer therapy.

Biological effects of a de novo designed myxoma virus peptide analogue: evaluation of cytotoxicity on tumor cells.

Background: The Resonant Recognition Model (RRM) is a physico-mathematical model that interprets protein sequence linear information using digital signal processing methods. In this study the RRM concept was employed for structure-function analysis of myxoma virus (MV) proteins and the design of a short bioactive therapeutic peptide with MV-like antitumor/cytotoxic activity.

Methodology/principal Findings: The analogue RRM-MV was designed by RRM as a linear 18 aa 2.

Antibiotic susceptibility of coagulase-negative staphylococci isolated from very low birth weight babies: comprehensive comparisons of bacteria at different stages of biofilm formation.

Background: Coagulase-negative staphylococci are major causes of bloodstream infections in very low birth weight babies cared for in Neonatal Intensive Care Units. The virulence of these bacteria is mainly due to their ability to form biofilms on indwelling medical devices. Biofilm-related infections often fail to respond to antibiotic chemotherapy guided by conventional antibiotic susceptibility tests.

Densely adherent growth mode, rather than extracellular polymer substance matrix build-up ability, contributes to high resistance of Staphylococcus epidermidis biofilms to antibiotics.

Objectives: (i) To evaluate the role of the adherent growth mode and extracellular polymer substance build-up in biofilm resistance to antibiotics. (ii) To re-assess various mechanisms leading to biofilm resistance to antibiotics.

Methods: We compared the biofilm MICs, biofilm MBCs using the viable count method, biofilm MBCs based on broth recovery methods and minimum biofilm eradication concentrations (MBECs) of antistaphylococcal antibiotics for multilayer biofilms formed by 'biofilm-positive' S.

Comparison of various antimicrobial agents as catheter lock solutions: preference for ethanol in eradication of coagulase-negative staphylococcal biofilms.

Coagulase-negative staphylococci (CoNS) are the main causative agents of bacteraemia in infants managed in neonatal intensive care units (NICUs). Intraluminal colonization of long-term central venous catheters by these bacteria and subsequent biofilm formation are the prerequisites of the bloodstream infections acquired in NICUs. The catheter lock technique has been used to treat catheter colonization; however, the optimum choice of antimicrobial agents and their corresponding concentrations and exposure times have not been determined.

Characterization of Campylobacter concisus hemolysins.

Campylobacter concisus is an opportunistic pathogen commonly found in the human oral cavity. It has also been isolated from clinical sources including gastroenteritis cases. Both secreted and cell-associated hemolytic activities were detected in C.

Detection of Salmonella spp. in retail raw food samples from Vietnam and characterization of their antibiotic resistance.

A study was conducted to examine the levels of Salmonella spp. contamination in raw food samples, including chicken, beef, pork, and shellfish, from Vietnam and to determine their antibiotic resistance characteristics. A total of 180 samples were collected and examined for the presence of Salmonella spp.

Phospholipase A in Gram-negative bacteria and its role in pathogenesis.

Phospholipase A (PLA) is one of the few enzymes present in the outer membrane of Gram-negative bacteria, and is likely to be involved in the membrane disruption processes that occur during host cell invasion. Both secreted and membrane-bound phospholipase A(2) activities have been described in bacteria, fungi and protozoa. Recently there have been increasing reports on the involvement of PLA in bacterial invasion and pathogenesis.

SmpB: a novel outer membrane protein present in some Brachyspira hyodysenteriae strains.

A novel outer membrane protein-encoding gene was identified in Brachyspira hyodysenteriae. The predicted protein, SmpB, was encoded by a gene that contains regions of identity with that encoding the previously identified lipoprotein SmpA. However, the majority of the reading frame encoding SmpA and SmpB share no detectable similarity.

Characterization of a haemolytic phospholipase A(2) activity in clinical isolates of Campylobacter concisus.

A membrane-bound, haemolytic phospholipase A(2) (PLA(2)) activity was detected in clinical strains of Campylobacter concisus isolated from children with gastroenteritis. The clinical strains were assigned into two molecular groups (genomospecies) based on PCR amplification of their 23S rDNA. This calcium-dependent, heat-stable, haemolytic PLA(2) activity was detected in strains from both genomospecies.