Metal-based nanoparticles: an alternative treatment for biofilm infection in hard-to-heal wounds.

Metal-based nanoparticles (MNPs) are promoted as effective compounds in the treatment of bacterial infections and as possible alternatives to antibiotics. These MNPs are known to affect a broad spectrum of microorganisms using a multitude of strategies, including the induction of reactive oxygen species and interaction with the inner structures of the bacterial cells. The aim of this review was to summarise the latest studies about the effect of metal-based nanoparticles on pathogenic bacterial biofilm formed in wounds, using the examples of Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Pseudomonas aeruginosa, as well as provide an overview of possible clinical applications.

The Prevalence of Tick-Borne Encephalitis Virus in Wild Rodents Captured in Tick-Borne Encephalitis Foci in Highly Endemic Lithuania.

Wild rodents are considered to be one of the most important TBEV-amplifying reservoir hosts; therefore, they may be suitable for foci detection studies. To investigate the effectiveness of viral RNA detection in wild rodents for suspected TBEV foci confirmation, we trapped small rodents (n = 139) in various locations in Lithuania where TBEV was previously detected in questing ticks. Murine neuroblastoma Neuro-2a cells were inoculated with each rodent sample to maximize the chances of detecting viral RNA in rodent samples. TBEV RNA was detected in 74.8% (CI 95% 66.7-81.1) of the brain and/or internal organ mix suspensions, and the prevalence rate increased significantly following sample cultivation in Neuro-2a cells. Moreover, a strong correlation (r = 0.88; p < 0.05) was found between the average monthly air temperature of rodent trapping and the TBEV RNA prevalence rate in cell culture isolates of rodent suspensions, which were PCR-negative before cultivation in cell culture. This study shows that wild rodents are suitable sentinel animals to confirm TBEV foci. In addition, the study results demonstrate that sample cultivation in cell culture is a highly efficient method for increasing TBEV viral load to detectable quantities.

Phylogenetic characterisation of tick-borne encephalitis virus from Lithuania.

The Baltic states are the region in Europe where tick-borne encephalitis (TBE) is most endemic. The highest notification rate of TBE cases is reported in Lithuania, where the incidence of TBE has significantly increased since 1992. A recent study reported 0.4% prevalence of TBE virus (TBEV) in the two most common tick species distributed in Lithuania, Ixodes ricinus and Dermacentor reticulatus, with the existence of endemic foci confirmed in seven out of Lithuania's ten counties. However, until now, no comprehensive data on molecular characterisation and phylogenetic analysis have been available for the circulating TBEV strains. The aim of this study was to analyse TBEV strains derived from I. ricinus and D. reticulatus ticks collected from Lithuania and provide a genotypic characterisation of viruses based on sequence analysis of partial E protein and NS3 genes. The 54 nucleotide sequences obtained were compared with 81 TBEV strains selected from the NCBI database. Phylogenetic analysis of the partial E and NS3 gene sequences derived from 34 Lithuanian TBEV isolates revealed that these were specific to Lithuania, and all belonged to the European subtype, with a maximum identity to the Neudoerfl reference strain (GenBank accession no. U27495) of 98.7% and 97.4%, respectively. The TBEV strains showed significant regional genetic diversity. The detected TBEV genotypes were not specific to the tick species. However, genetic differences were observed between strains from different locations, while strains from the same location showed a high similarity.

Prevalence of tick-borne encephalitis virus in questing Dermacentor reticulatus and Ixodes ricinus ticks in Lithuania.

The Baltic States are the region in Europe where tick-borne encephalitis (TBE) is most endemic, with one-third of the European TBE cases detected in Lithuania, Latvia and Estonia. With the Czech Republic and Germany, Lithuania has among the highest population incidences of TBE. Ticks from the Ixodidae family are the main vectors of the TBE virus (TBEV) in Europe. However, there is still a lack of data on the prevalence of TBEV in ticks in different parts of Lithuania. This study analysed the current prevalence of TBEV in the two most common tick species distributed in Lithuania: Ixodes ricinus and Dermacentor reticulatus. Questing I. ricinus (n = 7170) and D. reticulatus (n = 1676) ticks were collected from 81 locations in all ten counties of Lithuania between 2017 and 2019. The presence of TBEV was analysed using a real-time reverse transcription polymerase chain reaction (RT-PCR) and TBEV prevalence in ticks was calculated as the minimum infection rate (MIR). TBEV was detected in the three developmental stages (adults, nymphs and larvae) of I. ricinus and in D. reticulatus adults. The MIR of TBEV in the total sample of I. ricinus was 0.4 % (28/7170) and for D. reticulatus was also estimated to be 0.4 % (6/1676). TBEV-infected ticks were found in 16 locations in seven counties, with MIR ranging from 0.1 % to 1.0 %. The TBEV strains detected belong to the European subtype. To the best of the authors' knowledge, this is the first report on the prevalence of TBEV in unfed D. reticulatus ticks and in I. ricinus unfed larvae in Lithuania.

Whole-Genome Shotgun Sequence of Bacillus mycoides Strain U53, a Psychrotolerant Bacterium Isolated from the Sakhalin Region in Russia.

The shotgun genome sequence of Bacillus mycoides strain U53, a psychrotolerant bacterium that was isolated from soil in Russia, is characterized. The bacterial genome is 5,710,017 bp long and is predicted to have 5,847 genes. The GC content is 35.4%.

Agrobacterium rhizogenes-mediated transformation enhances the antioxidant potential of Artemisia tilesii Ledeb.

Plants belonging to the genus Artemisia L. have been used for medicinal purposes since ancient times. These aromatic plants produce and accumulate a wide range of potent secondary metabolites, many of which have shown antioxidant, antiparasitic, antimicrobial, anti-inflammatory, and even anticancer activities. Enhanced biosynthesis of these compounds is a prerequisite for comprehensive studies of their therapeutic properties and cost-efficient use. Transformation of plants with Agrobacterium rhizogenes native root locus (rol) genes is a promising approach to increase the biosynthesis of plant secondary metabolites. The aim of the present study was to evaluate the effects of A. rhizogenes-mediated transformation on the flavonoid contents in hairy roots of medicinal herb A. tilesii Ledeb. Transgenic A. tilesii hairy root lines were analyzed for stable integration of the rolB and rolC transgenes into the plant genome, total flavonoid contents, antioxidant activities of extracts, and the spatiotemporal expression of two flavonoid biosynthetic genes, phenylalanine ammonialyase (PAL) and chalcone synthase (CHS). The flavonoid contents of A. tilesii directly correlated with the antiradical activity and reducing power of their respective lines, with the greatest antioxidant activity found in the plants with the highest level of total flavonoids. Furthermore, all hairy root lines demonstrated altered expression of plant native PAL and CHS genes. Most importantly, A. rhizogenes-mediated transformation enhanced the biosynthesis of natural antioxidants in A. tilesii, producing almost twice the amount of flavonoids than controls. These findings provide an opportunity for the identification of the bioactive molecules in A. tilesii extracts and their potential health benefits.