Reactive magnetron plasma modification of electrospun PLLA scaffolds with incorporated chloramphenicol for controlled drug release

Surface modification with the plasma of the direct current reactive magnetron sputtering has demonstrated its efficacy as a tool for enhancing the biocompatibility of polymeric electrospun scaffolds. Improvement of the surface wettability of materials with water, as well as the formation of active chemical bonds in the near-surface layers, are the main reasons for the described effect. These surface effects are also known to increase the release rate of drugs incorporated in fibers. Herein, we investigated the effect of plasma modification on the chloramphenicol release from electrospun poly (lactic acid) fibrous scaffolds. Scaffolds with high—50 wt./wt.%—drug content were obtained. It was shown that plasma modification leads to an increase in the drug release rate and drug diffusion coefficient, while not deteriorating surface morphology and mechanical properties of scaffolds. The materials’ antibacterial activity was observed to increase in the first day of the experiment, while remaining on the same level as the unmodified group during the next six days. The proposed technique for modifying the surface of scaffolds will be useful for obtaining drug delivery systems with controlled accelerated release, which can expand the possibilities of local applications of antibiotics and other drugs

Defensive Structures of the Gremiachy Kliuch Hill-Fort

The article features the results of comprehensive research of defensive structures located in Gremiachiy Kliuch hillfort which corresponds to the Post-Maklasheevka culture of the Ananyino cultural and historical areal. The authors determined the starting time of construction activities (9th – mid-8th centuries B.C.) and the periodization of the erection of the hillfort's earth rampart using archaeological and natural scientific techniques (lithologic and stratigraphic, palynological and geomorphological). The second stage of the construction of defensive structures corresponds to mid-8th – first quarter of 7th centuries B.C. The moat was represented by a natural saddle located in the narrowest area of the headland platform between the ravines. The authors concluded that the rampart construction technique was very archaic, and the inner support wall was used as the foundation. Fine preservation of the earth rampart which has survived almost intact until the present day is accounted for by an optimal ratio of proportions (width and height), lithological composition of the soil and forest coverage of the site in the Post-Ananyino period

Synthesis and Structure of Iron (II) Complexes of Functionalized 1,5-Diaza-3,7-Diphosphacyclooctanes

In order to synthesize new iron (II) complexes of 1,5-diaza-3,7-diphosphacyclooctanes with a wider variety of the substituents on ligands heteroatoms (including functionalized ones, namely, pyridyl groups) and co-ligands, it was found that these ligands with relatively small phenyl, benzyl, and pyridin-2-yl substituents on phosphorus atoms in acetonitrile formed bis-P,P-chelate cis-complexes [L2Fe(CH3CN)2]2+ (BF4)2−, whereas P-mesityl-substituted ligand formed only monoligand P,P-complex [LFe(CH3CN)4]2+ (BF4)2−. 3,7-dibenzyl-1,5-di(1′-(R)-phenylethyl)-1,5-diaza-3,7-diphosphacyclooctane reacted with hexahydrate of iron (II) tetrafluoroborate in acetone to give an unusual bis-ligand cationic complex of the composition [L2Fe(BF4)]+ BF4−, where two fluorine atoms of the tetrafluoroborate unit occupied two pseudo-equatorial positions at roughly octahedral iron ion, according to X-ray diffraction data. 1,5-diaza-3,7-diphosphacyclooctanes replaced tetrahydrofurane and one of the carbonyl ligands of cyclopentadienyldicarbonyl(tetrahydrofuran)iron (II) tetrafluoroborate to form heteroligand complexes [CpFeL(CO)]+BF4−. The structural studies in the solid phase and in solutions showed that diazadiphosphacyclooctane ligands of all complexes adopted chair-boat conformations so that their nitrogen atoms were in close proximity to the central iron ion. The redox properties of the obtained complexes were performed by the cyclic voltammetry method

Combined Use of Antimicrobial Peptides with Antiseptics against Multidrug-Resistant Bacteria: Pros and Cons

Antimicrobial peptides (AMPs) are acknowledged as a promising template for designing new antimicrobials. At the same time, existing toxicity issues and limitations in their pharmacokinetics make topical application one of the less complicated routes to put AMPs-based therapeutics into actual medical practice. Antiseptics are one of the common components for topical treatment potent against antibiotic-resistant pathogens but often with toxicity limitations of their own. Thus, the interaction of AMPs and antiseptics is an interesting topic that is also less explored than combined action of AMPs and antibiotics. Herein, we analyzed antibacterial, antibiofilm, and cytotoxic activity of combinations of both membranolytic and non-membranolytic AMPs with a number of antiseptic agents. Fractional concentration indices were used as a measure of possible effective concentration reduction achievable due to combined application. Cases of both synergistic and antagonistic interaction with certain antiseptics and surfactants were identified, and trends in the occurrence of these types of interaction were discussed. The data may be of use for AMP-based drug development and suggest that the topic requires further attention for successfully integrating AMPs-based products in the context of complex treatment. AMP/antiseptic combinations show promise for creating topical formulations with improved activity, lowered toxicity, and, presumably, decreased chances of inducing bacterial resistance. However, careful assessment is required to avoid AMP neutralization by certain antiseptic classes in either complex drug design or AMP application alongside other therapeutics/care products

Consequences of COVID-19 infection for child health and wellbeing: protocol for a prospective, observational, longitudinal study in children

The novel coronavirus disease 2019 (COVID-19) pandemic has a detrimental impact on the physical and mental health of many children and their families worldwide. Although most children have mild disease, some develop severe complications, with multisystem inflammatory syndrome being the most well-described. Recent reports suggest that COVID-19 may not fully resolve even months after the end of the acute phase. There is a lack of harmonised longitudinal data on short- and long-term consequences of COVID-19 infection in children. Hence, an observational study is needed to evaluate the consequences of COVID-19 in the paediatric population. Methods and analysis This protocol describes a prospective, observational, longitudinal study in paediatric patients previously diagnosed with COVID-19 in hospital and/or primary care/ community settings. The aim of the study is to include children and adolescents (0 to 17 years old) at different sites internationally. Participants will be enrolled and followed up for up to 3 years. Basic (Tier 1) data will include the following: COVID-19 clinical characteristics during acute phase; child comorbidities; treatments received; child or caregiver-reported outcomes on health and wellbeing and impact of daily living; readmission rate. Additional symptom-specific (Tier 2) data may be collected in a subgroup of patients that are experiencing persistent problems. Ethics and dissemination This study will be conducted in accordance with the principles established by the 18th World Medical Assembly and all subsequent amendments and the guidelines for Good Epidemiology Practice. Each individual country joining this study assures that ethics approval are in place and local regulatory requirements met before commencing the study. The anonymised data may be disseminated via publications in peer-reviewed journals, presentations at workshops and conferences, and the public domain by press releases and social media