Passivated Porous Silicon Membranes and Their Application to Optical Biosensing

A robust fabrication method for stable mesoporous silicon membranes using standard microfabrication techniques is presented. The porous silicon membranes were passivated through the atomic layer deposition of different metal oxides, namely aluminium oxide Al2O3, hafnium oxide HfO2 and titanium oxide TiO2. The fabricated membranes were characterized in terms of morphology, optical properties and chemical properties. Stability tests and optical probing noise level determination were also performed. Preliminary results using an Al2O3 passivated membranes for a biosensing application are also presented for selective optical detection of Bacillus Cereus bacterial lysate. The biosensor was able to detect the bacterial lysate, with an initial bacteria concentration of 106 colony forming units per mL (CFU/mL), in less than 10 min.

Immunoprophylaxis of influenza, acute and recurrent respiratory infections during the COVID-19 pandemic

The article notes features of the last epidemic season (2020-2021) in the form of extremely low activity of influenza viruses with SARS-CoV-2 remaining dominant in the etiological structure of acute respiratory viral infections. Presented own data indicating the heterogeneity of SARS-CoV-2 (Alpha, Delta, B.1.1.317, B.1.1.397, B.1.1.523) isolated from hospitalized patients was noted. An increase in the etiological role of bocavirus, alpha-coronavirus and metapneumovirus with a decrease in the frequency of parainfluenza viruses, adenoviruses, rhinoviruses and respiratory syncytial virus was established. An unusual shift of the period of maximum activity of respiratory syncytial virus to the 20th week was noted. Attention is paid to the need during the ongoing pandemic COVID-19 to fully immunize children as part of the National Immunization Calendar, also emphasized the role of mandatory annual vaccination against influenza. It is noted that the maximum protective effect of immunoprophylaxis of influenza acute and recurrent respiratory infections can be achieved with a combination of vaccination with bacterial lysates. The article presents a review of the literature and our data demonstrating the safety, good tolerability, and high clinical and immunological efficiency of polyvalent mechanical bacterial lysate for the prevention of acute and recurrent respiratory infections in children. It is shown that the use of polyvalent mechanical bacterial lysate during the prevaccination period makes it possible to substantially reduce the frequency of intercurrent infections, which reduces the number of temporary medical withdrawals and increases the coverage of vaccinations against influenza in organized groups to 85.1%. The role of trained immunity as one of the possible mechanisms providing nonspecific immunoprophylaxis during influenza vaccination and the use of bacterial lysates is discussed.

Histological study of the effect of bacterial lysates on the state of periodontal tissue in experimental periodontitis in rats

The aim of the research: to experimentally study at the histological and morphological level the degree of the corrective effect of bacterial lysate of the disturbed non-specific defense of the body on the model of periodontitis based on the Central Research Laboratory of the National University of Pharmacy. Materials and methods: prospective study has been conducted on experimental periodontitis in 42 rats for 90 days. The animals were treated with «Respibron» and the reference drug «Imudon». Histological and morphometric studies were carried out according to standard methods. Micropreparations were viewed under a Granum DCM 310 digital video camera. All interventions and euthanasia of animals were carried out in compliance with the European principles. Results: by the end of 90 days of experimental periodontitis at the local level in the homogenate of animal gum tissue compensatory mechanisms are depleted and differed from the norm by 397 times. The dynamics of the studied morphometric and histological parameters of "Respibron" was similar to the "Imudon", but the magnitude of destruction was less pronounced and differed at the end of the experiment by 17.2 times in comparison with the intact control, and in the control group the results improved by 23.1 times. Conclusion: the obtained data from the study indicate a high decompensation of experimental periodontitis. It is characterized by the formation of periodontal pockets and inflammatory bone loss. The magnitude of destruction differed from the norm by 397 times. Applying of bacterial lysates led to the compensation of bacterial dysbiosis, restoration of the tissues of paradont. The therapeutic effect of "Respibron" can be assessed as more powerful in comparison with "Imudon" in terms of the studied morphometric and histological parameters: the magnitude of improvement "Respibron" was 3.72 times higher than the indicators of "Imudon". We should continue the study of experimental periodontitis as mechanisms of development, protection, and restoration of tissues under conditions of pharmacological correction by bacterial lysate "Respibron"

Study of influence of bacterial lysate on cytokine indicators in experimental periodontis in rats

The aim of the research: to optimize the treatment of patients with a disturbed cytokine profile by a bacterial lysate in an experimental model of periodontitis against the background of changes in the local and systemic immune response. Materials and methods: prospective study has been conducted on experimental periodontitis in 42 rats for 90 days. The animals were treated by solution of «Respibron» and the reference drug «Imudon». The concentration of cytokines in the blood serum was determined by the enzyme immunoassay, circulating immune complexes – precipitation method is measured on a spectrophotometer, C-reactive protein – using a latex diagnosticum. All interventions and euthanasia of animals were carried out in compliance with the European principles. Results: the obtained data from the study indicate a high degree a state of decompensation of experimental periodontitis. An immuno-inflammatory reaction preceding periodontitis is accompanied by the disturbances of the cytokine balance, local and systemic immune response. Applying of bacterial lysates led to the compensation of bacterial dysbiosis, restoration of the balance of the activity of pro- and anti-inflammatory cytokines, and a decrease the hyperactivity of immunological markers. Conclusion: the studies carried out have shown that the use of bacterial lysate is a pathogenetically substantiated component of therapeutic tactics. The normalizing effect of the lysate on the parameters of the immune response and cytokine profile has been reliably shown. Considering the immuno-inflammatory reaction at the experimental periodontitis, accompanied by the cytokine imbalance, study the pharmacological correction by bacterial lysate should continue from the point of view of establishing the mechanisms of development, protection, and restoration of tissues. It has been proved that by the end of the 90-day period of observation of the course of experimental periodontitis, the power of natural compensatory mechanisms acquired a state of decompensation. It has manifested by increased pro-inflammatory cytokine IL-1β in 1.7 times, and TNF-α in 3 times, decreased anti-inflammatory cytokine IL-10 in 1.6 times; increased the concentration of CIC in the blood in 2 times, C-reactive protein in 4.4 times at the local level in the gum tissue homogenate of the control pathology group of animals. The powerful corrective effect of bacterial lysates «Respibron» and «Imudon» on the indicators of the cytokine series on the model of chronic experimental periodontitis has been reliably established. The normalizing effect is due to the compensation of bacterial dysbiosis, restoration of the balance of the activity of pro- and anti-inflammatory cytokines, and a decrease in the hyperactivity of immunological markers. The therapeutic effect of «Respibron» (bacterial lysate of 13 strains of microorganisms) can be assessed as expressive and more powerful in comparison with «Imudon». The obtained results make it possible to continue the study of the course of experimental periodontitis from the point of view of establishing the mechanisms of development, protection, and restoration of tissues under conditions of pharmacological correction with bacterial lysate «Respibron».

STUDY OF THE INFLUENCE OF BACTERIAL LYSATE ON INDICATORS OF LYSOSOMAL PHOSPHATASE ACTIVITY IN EXPERIMENTAL PERIODONTITIS IN RATS

Introduction. One of the stages of the pathophysiological study of the parameters of mineral metabolism of alkaline (ALP) and acidic (AP) phosphatases – enzymes of bone tissue of osteoblast and osteoblast membranes in experimental periodontitis against the background of the use of bacterial lysate Respibron® was carried out. Materials and methods. Experimental periodontitis in rats was in the modification of O.I. Sukmansky. There were rats with experimental periodontitis and rats treated by Respibron (10 mg/kg 1 time per day) or Imudon for 30 days. Determination of alkaline (ALP) and acidic (AP) phosphatases activity (pH 4.8 and 10.5) was performed according to the methodological recommendations of AP Levitsky et al. Discussion of results. It was found that by the end of the 90-day period of the experiment, a statistically stable course of chronic damage to the periodontium was observed in terms of ALP and AP, which exceeded the intact ones by 1.93 and 1.4 times, respectively, which reflects the hypoergic state of chronic periodontal inflammation. A powerful corrective effect of the drugs Respibron® and Imudon® on markers of osteoblast and osteoblast activity in experimental periodontitis has been proven. Established a stimulating effect on osteoregeneration Respibron® in the hypoergic course of the inflammatory process. The therapeutic effect of Respibron® is more expressive and powerful compared to Imudon®. Conclusions.The results obtained make it possible to continue the study of the course of experimental periodontitis in order to establish the mechanisms of development, protection, and restoration of tissues under the conditions of the pharmacological correction Respibron®.

Use of the Bacterial Lysate OM-85 in the Paediatric Population in Italy: A Retrospective Cohort Study

Background: In Italy, the bacterial lysate OM-85 (Broncho-Vaxom®, Broncho-Munal®, Ommunal®, Paxoral®, Vaxoral®) is registered for the prophylaxis of recurrent respiratory tract infections (RTIs) in adults and children above one year of age, but there are limited data on its use in the paediatric population. We aim to estimate the impact of OM-85 treatment on RTIs and antibiotic prescriptions in children. Methods: This study included children aged 1 to 14 years enrolled in Pedianet, a paediatric general practice research database, from January 2007 to June 2017, having at least one prescription of OM-85. Children with less than 12 months of follow-up before (PRE period) and after (POST period) the OM-85 prescription were excluded. The frequency of antibiotic prescriptions and the frequency of RTI episodes in the PRE and POST periods were compared through the post-hoc test. Subgroup analysis was performed in children with recurrent RTIs. Results: 1091 children received 1382 OM-85 prescriptions for a total follow-up of 619,525.5 person-years. Overall, antibiotic prescriptions decreased from a mean of 2.8 (SD (standard deviation) 2.7) prescriptions in the PRE period to a mean of 2.2 (SD 2.6) prescriptions in the POST period (p < 0.0001). RTIs decreased from a mean of 3.4 (SD 2.9) episodes in the PRE period to a mean of 2.5 (SD 2.6) episodes in the POST period (p < 0.0001). No change in antibiotic class was noted, and co-amoxiclav remained the preferred therapy in 28% of cases, followed by amoxicillin. These results were confirmed among children with recurrent RTIs. Conclusions: OM-85 is effective in preventing both antibiotic prescriptions and RTIs in children.