Efficacy assessment of PEV2 phage on Galleria mellonella larvae infected with a Pseudomonas aeruginosa dog otitis isolate.

Pseudomonas (P.) aeruginosa is the most frequently isolated Gram-negative bacteria in dog otitis. Antimicrobial resistance is particularly prevalent in P. aeruginosa and phage therapy represents a promising alternative therapeutic strategy. The aim of this study was to assess the efficacy of the PEV2 phage against a clinical P. aeruginosa isolate from a canine otitis using a Galleria (G.) mellonella larvae model. The genomic DNA of PAV237 P. aeruginosa isolate was sequenced and analysed. In a first main experiment, the efficacy of PEV2 phage against PAV237 was assessed at different multiplicities of infection (MOI) (50,000, 5000, 500, 50) by analyzing the larvae survival rate during 4 days. In a second experiment, the bacterial and phage titer evolutions were assessed depending on two MOIs (50,000, 5000). No significant survival increase was observed with PEV2 therapy in the infected larvae groups. The generated Kaplan-Meier curves showed that the rate of alive larvae was significantly higher in the non-infected larvae compared to the infected-treated ones irrespective of phage MOIs. An increase of the phage titer was observed at 24 and 48 h post-inoculation (HPI) with both MOIs and the P. aeruginosa titers were lower with MOI 50,000 and 5000 compared to the infectivity control at 24 and 48 HPI. Even if an ineffectiveness of the PEV2 phage was observed on the larvae survival, PEV2 is active against P. aeruginosa in this model and PEV2 replication is correlated with a lower bacterial proliferation in the phage treated larvae.

Bacteriophage-derived enzyme that depolymerizes the alginic acid capsule associated with cystic fibrosis isolates of Pseudomonas aeruginosa.

AIMS: To identify enzymes associated with bacteriophages infecting cystic fibrosis (CF) strains of Pseudomonas aeruginosa that are able to degrade extracellular alginic acids elaborated by the host bacterium. METHODS AND RESULTS: Plaques produced by 21 Ps. aeruginosa-specific phages were screened for the presence of haloes, an indicator of capsule hydrolytic activity. Four phages produced haloed plaques, and one (PT-6) was investigated further. PT-6 was shown by electron microscopy to belong to Podoviridae family C1, to reduce the viscosity of four alginate preparations using a rolling ball viscometer and to release uronic acid-containing fragments from the polymers, as judged by spectrophotometry and thin layer chromatography. The alginase was partially purified by gel filtration chromatography and shown to be a 37 kDa polypeptide. CONCLUSIONS: Infection of CF strains of Ps. aeruginosa by phage PT-6 involves hydrolysis of the exopolysaccharide secreted by the host. SIGNIFICANCE AND IMPACT OF THE STUDY: The alginase produced by PT-6 has the potential to increase the well-being of CF suffers by improving the surface properties of sputum, accelerating phagocytic uptake of bacteria and perturbing bacterial growth in biofilms.

[Effects of metabolic triad (25% polarizing solution, mildronat, preductal MR) in acute myocardial infarction].

The aim of the work was to study the effect of metabolic triad with different mechanisms of acting--high-dose Glucose-Insulin-Potassium--25% polarizing solution (25% glucose, 50 IU soluble insulin and 4% 144 ml KCL-GIK), mildronat, preductal MR on the functional condition of heart during the acute myocardial infarction. 20 patients from the main group and 20 from the control one have been under the study. Patients with diabetes and heavy forms of heart failure (killip class>2) were not included in the study. Evaluation of the functional condition of heart was based on ECG and echocardiography data received before and after the treatment. It was determined that the frequency of the rhythm disorder decreases in the conditions of metabolic triad as well as during the thrombolitic reperfusion. Average period of time for normalization of S-T segment elevation made up 5.4+/-1.8 days and 7.3+/-1.2 days in case of the control group. The received data make it relevant to include the complex metabolic triad for preventive purpose during the complications followed after the acute myocardial infarction.

[Diagnosis of vestibular disorders in the hypothalamic syndrome]. / O diagnostike vestibuliarnykh narushenii pri gipotalamicheskom sindrome.

Employing clinical and electrophysiological research methods, 40 patients with the hypothalamic syndrome (HS) were examined with special emphasis on the function of the vestibular system. Polygraphic recording (EEG, ENG, EMG and ECG) was made in the alert state, during drug-induced sleep, and immediately after awakening. An analysis of the clinical and electrophysiological correlations prompted the conclusion that the HS is associated with variable disturbances of vestibular function which objectively confirm the presence of the HS and may contribute to the differential diagnosis of the disease.