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Scientific Reports Feb 2024The phlorotannin-polycaprolactone-coated endotracheal tube (PP tube) has been developed with the aim of preventing tracheal stenosis that can result from endotracheal...
The phlorotannin-polycaprolactone-coated endotracheal tube (PP tube) has been developed with the aim of preventing tracheal stenosis that can result from endotracheal intubation, a factor that can lead to a serious airway obstruction. Its preventive efficacy has been assessed through both in vitro and in vivo investigations. However, there is a lack of studies concerning its biocompatibility and sub-chronic toxicity in animal models, a crucial factor to ensure the safety of its usage as a functional endotracheal tube. Thus, this study aimed to evaluate the biocompatibility and sub-chronic (13 weeks) toxicity of the PP tube through L929 cell line and diverse in vivo models. The cytotoxicity testing was performed using the extracts of PP tube on L929 cells for 72 h. Furthermore, other tests conducted on animal models, including ICR mice (acute systemic toxicity), New Zealand white rabbit (intradermal reactivity and pyrogen tests), guinea pig (maximization sensitization), and Sprague Dawley rats (sub-chronic toxicity). In both biocompatibility and sub-chronic toxicity analyses, no significant adverse effects are observed in the groups exposed to the PP tube, when compared to control group. Altogether, the findings suggested that the PP tube exhibits relative non-toxic and safety, supporting its suitability for clinical usage. However, extended periods of intubation may produce mild irritant responses, highlighting the clinical caution of limiting intubation duration to less than 13 weeks.
Topics: Mice; Rats; Animals; Rabbits; Guinea Pigs; Trachea; Rats, Sprague-Dawley; Mice, Inbred ICR; Intubation, Intratracheal; Polyesters
PubMed: 38365854
DOI: 10.1038/s41598-024-54684-8 -
BMC Complementary Medicine and Therapies Feb 2024Modern medicine is not the choice of patients with "shimetere" in the Gurage community owing to their perception of 'parenteral medication use severely aggravates the...
BACKGROUND
Modern medicine is not the choice of patients with "shimetere" in the Gurage community owing to their perception of 'parenteral medication use severely aggravates the disease'. For this reason, the root part of Polygala sadebeckiana Gürke is commonly utilized as traditional medicine in the management of the disease. The aim of this study was to evaluate the antimicrobial activity of Polygala sadebeckiana Gürke extract on bacterial isolates from wound samples of patients with "Shimetere".
METHODS
The agar well diffusion method was used to evaluate antibacterial activity, and the agar dilution method was utilized to determine minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MICs). The crude extract was tested against isolated bacteria at concentrations of 25, 50, 75 and 100 mg/mL in triplicate (3x). The positive controls were azithromycin (15 µg) and cloxacillin disk (5 µg), and the negative control was dimethylsulfoxide (5%). The group mean comparisons were made using one-way ANOVA at a significance level of p < 0.05, and the results are presented as the mean ± standard deviation. The presence of secondary metabolites from crude extract was checked by standard testing procedures.
RESULTS
S. aureus and S. pyrogen were the two identified bacteria from 9 (60%) and 3 (20%) wound samples, respectively. All identified bacterial strains were susceptible to the reference antibiotics. Tannins and saponins were the most abundant secondary metabolites found in the crude extracts. The average inhibition zones of the plant extracts with 100, 75, 50 and 25 mg/mL concentrations were 27, 20.33, 15.25, and 11.96 mm (p < 0.000) for S. aureus and 30.02, 24.50, 19.07, and 15.77 mm (p < 0.000) for S. pyrogen bacteria, respectively. The MIC and MBC of the crude extract were 1.67 and 10 mg/mL for S. aureus and 0.98 and 4 mg/mL for S. pyrogen.
CONCLUSION
Polygala sadebeckiana Gürke contained significant tannins and saponins as secondary metabolites and had antibacterial activities against isolated bacteria (S. aureus and S. pyrogen) from "Shimetere". The potential mechanism of antibacterial action of the plant extract was cell wall synthesis inhibition.
Topics: Humans; Polygala; Tannins; Staphylococcus aureus; Agar; Pyrogens; Plant Extracts; Anti-Bacterial Agents; Bacteria; Phytochemicals; Saponins
PubMed: 38302996
DOI: 10.1186/s12906-024-04371-y -
Environmental Science & Technology Feb 2024With the increased occurrences of wildfires worldwide, there has been an increase in scientific interest surrounding the chemistry of fire-derived "black" carbon (BC)....
With the increased occurrences of wildfires worldwide, there has been an increase in scientific interest surrounding the chemistry of fire-derived "black" carbon (BC). Traditionally, wildfire research has assumed that condensed aromatic carbon (ConAC) is produced via combustion, and thus, ConAC is equated to BC. However, the lack of correlations between ConAC in soils or rivers and wildfire history suggests that ConAC may be produced non-pyrogenically. Here, we show quantitative evidence that this occurs during the oxidation of biomass with environmentally ubiquitous hydroxyl radicals. Pine wood boards exposed to iron nails and natural weather conditions for 12 years yielded a charcoal-like ConAC-rich material. ConAC was also produced during laboratory oxidations of pine, maple, and brown-rotted oak woods, as well as algae, corn root, and tree bark. Back-of-the-envelope calculations suggest that biomass oxidation could be producing massive non-pyrogenic ConAC fluxes to terrestrial and aquatic environments. These estimates (e.g., 163-182 Tg-ConAC/year to soils) are much higher than the estimated pyrogenic "BC" fluxes (e.g., 128 Tg-ConAC/year to soils) implying that environmental ConAC is primarily non-pyrogenic. This novel perspective suggests that wildfire research trajectories should shift to assessing non-pyrogenic ConAC sources and fluxes, developing new methods for quantifying true BC, and establishing a new view of ConAC as an intermediate species in the biogeochemical processing of biomass during soil humification, aquatic photochemistry, microbial degradation, or mineral-organic matter interactions. We also advise against using BC or pyrogenic carbon (pyC) terminologies for ConAC measured in environmental matrices, unless a pyrogenic source can be confidently assigned.
Topics: Biomass; Carbon; Charcoal; Fires; Soot; Soil
PubMed: 38294931
DOI: 10.1021/acs.est.3c05448 -
Biodiversity Data Journal 2024More than 30 articles concerning spiders' diversity and assemblages' structure within the Visimskiy Reserve have been published since its establishment 52 years ago. The...
BACKGROUND
More than 30 articles concerning spiders' diversity and assemblages' structure within the Visimskiy Reserve have been published since its establishment 52 years ago. The literature provides data on 260 recorded species, one of which has been described as a new species. The majority of these records were not annotated. The peak of publication activity was in the 2 part of the 1990s and the beginning of the 21 century. The greatest amount of material was collected between 2012 and 2018, within long-term plots with quantitative observations of epigean and litter-dwelling spiders, focusing on wind-throw and post-fire successions.
NEW INFORMATION
This article summarises all the literature and field primary data. We also list 18 species new to the reserve's fauna, which currently comprises 278 species. Doubtful and invalid records have been excluded from the species list. The occurrences in the dataset are supported by detailed information about vegetation cover at the time of collection. This is important in the context of research on fauna and community changes along the vegetation succession, including wind-thrown and post-fire restoration.
PubMed: 38283141
DOI: 10.3897/BDJ.12.e114930 -
Antibiotics (Basel, Switzerland) Jan 2024Toxic shock syndrome (TSS) is a rare, life-threatening, toxin-mediated infectious process linked, in the vast majority of cases, to toxin-producing strains of or . The... (Review)
Review
Toxic shock syndrome (TSS) is a rare, life-threatening, toxin-mediated infectious process linked, in the vast majority of cases, to toxin-producing strains of or . The pathophysiology, epidemiology, clinical presentation, microbiological features, management and outcome of TSS are described in this review. Bacterial superantigenic exotoxins induces unconventional polyclonal lymphocyte activation, which leads to rapid shock, multiple organ failure syndrome, and death. The main described superantigenic exotoxins are toxic shock syndrome toxin-1 (TSST-1) and enterotoxins for and exotoxins (SpE) A, B, and C and streptococcal superantigen A (SsA) for . Staphylococcal TSS can be menstrual or nonmenstrual. Streptococcal TSS is linked to a severe group A streptococcal infection and, most frequently, to a necrotizing soft tissue infection. Management of TSS is a medical emergency and relies on early detection, immediate resuscitation, source control and eradication of toxin production, bactericidal antibiotic treatment, and protein synthesis inhibiting antibiotic administration. The interest of polyclonal intravenous immunoglobulin G administration as an adjunctive treatment for TSS requires further evaluation. Scientific literature on TSS mainly consists of observational studies, clinical cases, and in vitro data; although more data on TSS are required, additional studies will be difficult to conduct due to the low incidence of the disease.
PubMed: 38247655
DOI: 10.3390/antibiotics13010096 -
Archives of Microbiology Dec 2023Vibrio parahaemolyticus is a significant cause of seafood-associated gastroenteritis and pestilence in aquaculture worldwide. Despite extensive research, strategies for...
Vibrio parahaemolyticus is a significant cause of seafood-associated gastroenteritis and pestilence in aquaculture worldwide. Despite extensive research, strategies for protein depletion in this pathogen remain limited. Herein, we constructed a new CRISPR interference (CRISPRi) system for gene repression based on the combination of a shuttle vector pVv3 and the nuclease-null Cas9 variant (dead Cas9, or dCas9) from Streptococcus pyrogens. This CRISPRi is induced by adding both IPTG and arabinose. We showed that gene repression is scalable via the use of multiple sgRNAs. We also demonstrated that this gene repression can be precisely tuned by adjusting the amount of two different inducers and can be reversed by removing the inducers. This system provides a simple approach for selective gene repression on a genome-wide scale in V. parahaemolyticus. Application of this system will dramatically accelerate investigations of this bacterium, including studies of physiology, pathogenesis, and drug target discovery.
Topics: Vibrio parahaemolyticus; RNA, Guide, CRISPR-Cas Systems; Aquaculture; Arabinose; Drug Discovery
PubMed: 38147133
DOI: 10.1007/s00203-023-03770-y -
Bulletin of Environmental Contamination... Dec 2023The whale shark (Rhincodon typus) is a filter-feeding organism that can be considered a sentinel species, and Bahía de los Ángeles (BLA) in the Gulf of California is...
The whale shark (Rhincodon typus) is a filter-feeding organism that can be considered a sentinel species, and Bahía de los Ángeles (BLA) in the Gulf of California is an important sighting site for these elasmobranchs. This filter-feeding organism can be considered a pollutant sampler from the marine environment. Persistent organic pollutants are toxic compounds with high mobility and environmental persistence, bioaccumulation and trophic transfer. Among these are polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs). The present work aimed to determine concentrations of PAHs and OCPs in whale shark skin biopsies, collected in 2021 at BLA. Mean detected levels of PAHs and OCPs were 279.4 ng/g dw (dry weight) and 1478.1 ng/g dw, respectively. Analysis of similarities between the ordered sizes (4.2-7.6 m) and the concentrations of PAHs and OCPs indicated no significant differences. Individual PAHs detected indicate pyrogenic and petrogenic sources; the presence of pesticides at levels higher than those of hydrocarbons may be related to agricultural activity in the areas surrounding the Baja California peninsula. This study is the first report of PAH levels in R. typus for the Gulf of California and Mexico.
Topics: Animals; Mexico; Environmental Monitoring; Persistent Organic Pollutants; Brazil; Los Angeles; Pesticides; Hydrocarbons, Chlorinated; Sharks; Polycyclic Aromatic Hydrocarbons; Biopsy; Water Pollutants, Chemical
PubMed: 38141110
DOI: 10.1007/s00128-023-03841-2 -
Vaccines Nov 2023Creating an effective and safe vaccine is critical to fighting the coronavirus infection successfully. Several types of COVID-19 vaccines exist, including inactivated,...
Creating an effective and safe vaccine is critical to fighting the coronavirus infection successfully. Several types of COVID-19 vaccines exist, including inactivated, live attenuated, recombinant, synthetic peptide, virus-like particle-based, DNA and mRNA-based, and sub-unit vaccines containing purified immunogenic viral proteins. However, the scale and speed at which COVID-19 is spreading demonstrate a global public demand for an effective prophylaxis that must be supplied more. The developed products promise a bright future for SARS-CoV-2 prevention; however, evidence of safety and immunogenicity is mandatory before any vaccine can be produced. In this paper, we report on the results of our work examining the safety, toxicity, immunizing dose choice, and immunogenicity of QazCoVac-P, a Kazakhstan-made sub-unit vaccine for COVID-19. First, we looked into the product's safety profile by assessing its pyrogenicity in vaccinated rabbit models and using the LAL (limulus amebocyte lysate) test. We examined the vaccine's acute and sub-chronic toxicity on BALB/c mice and rats. The vaccine did not cause clinically significant toxicity-related changes or symptoms in our toxicity experiments. Finally, we performed a double immunization of mice, ferrets, Syrian hamsters, and rhesus macaques (Macaca mulatta). We used ELISA to measure antibody titers with the maximum mean geometric titer of antibodies in the animals' blood sera totaling approximately 8 log2. The results of this and other studies warrant recommending the QazCoVac-P vaccine for clinical trials.
PubMed: 38140175
DOI: 10.3390/vaccines11121771 -
Microbial Genomics Dec 2023The standalone regulator RofA is a positive regulator of the pilus locus in . Found in only certain genotypes, RofA has been reported to regulate other virulence...
The standalone regulator RofA is a positive regulator of the pilus locus in . Found in only certain genotypes, RofA has been reported to regulate other virulence factors, although its role in the globally dominant 1 is unclear. Given the recent emergence of a new 1 (M1) toxigenic lineage that is distinguished by three non-synonymous SNPs in , we characterized the regulon in six 1 strains that are representative of the two contemporary major 1 lineages (M1 and M1) using RNAseq analysis, and then determined the specific role of the M1-specific SNPs. Deletion of in three M1 strains led to altered expression of 14 genes, including six non-pilus locus genes. In M1 strains, deletion of led to altered expression of 16 genes, including nine genes that were unique to M1. Only the pilus locus genes were common to the RofA regulons of both lineages, while transcriptomic changes varied between strains even within the same lineage. Although introduction of the three SNPs into did not impact gene expression in an M1 strain, reversal of three SNPs in an M1 strain led to an unexpected number of transcriptomic changes that in part recapitulated transcriptomic changes seen when deleting RofA in the same strain. Computational analysis predicted that interactions with a key histidine residue in the PRD domain of RofA would differ between M1 and M1. RofA is a positive regulator of the pilus locus in all 1 strains but effects on other genes are strain- and lineage-specific, with no clear, common DNA binding motif. The SNPs in that characterize M1 may impact regulation of RofA; whether they alter phosphorylation of the RofA PRD domain requires further investigation.
Topics: Streptococcus pyogenes; Regulon; Bacterial Proteins; Pandemics; United Kingdom
PubMed: 38117674
DOI: 10.1099/mgen.0.001159 -
Scientific Reports Dec 2023The northeastern Pacific (NEP) Ocean spans the coast of British Columbia (Canada) and is impacted by anthropogenic activities including oil pipeline developments,...
The northeastern Pacific (NEP) Ocean spans the coast of British Columbia (Canada) and is impacted by anthropogenic activities including oil pipeline developments, maritime fossil fuel tanker traffic, industrial chemical effluents, agricultural and urban emissions in tandem with stormwater and wastewater discharges, and forest wildfires. Such events may expose surrounding marine environments to toxic polycyclic aromatic hydrocarbons (PAHs) and impact critical habitats of threatened killer whales (Orcinus orca). We analyzed skeletal muscle and liver samples from stranded Bigg's killer whales and endangered Southern Resident killer whales (SRKWs) for PAH contamination using LRMS. C3-phenanthrenes/anthracenes (mean: 632 ng/g lw), C4-dibenzothiophenes (mean: 334 ng/g lw), and C4-phenanthrenes/anthracenes (mean: 248 ng/g lw) presented the highest concentrations across all tissue samples. Diagnostic ratios indicated petrogenic-sourced contamination for SRKWs and pyrogenic-sourced burdens for Bigg's killer whales; differences between ecotypes may be attributed to habitat range, prey selection, and metabolism. A mother-fetus skeletal muscle pair provided evidence of PAH maternal transfer; low molecular weight compounds C3-fluorenes, dibenzothiophene, and naphthalene showed efficient and preferential exposure to the fetus. This indicates in-utero exposure of PAH-contamination to the fetus. Our results show that hydrocarbon-related anthropogenic activities are negatively impacting these top predators; preliminary data found here can be used to improve oil spill and other PAH pollution management and regulation efforts, and inform policy to conserve killer whale habitats in the NEP.
Topics: Animals; Polycyclic Aromatic Hydrocarbons; Whale, Killer; British Columbia; Phenanthrenes; Anthracenes; Environmental Monitoring
PubMed: 38114485
DOI: 10.1038/s41598-023-45306-w