Microorganisms最新文献

Introduction: Healthcare-associated infections (HAIs) pose a significant global challenge, resulting in prolonged hospital stays, higher healthcare costs, and increased morbidity and mortality rates. Reusable medical equipment, such as tourniquets, represents a potential vector for infection transmission. Despite frequent use and close contact with patients' skin, infection control protocols often overlook these devices. This study examines microbial contamination on the surface of reusable tourniquets in both emergency department and operating theatre settings.

Methods: A cross-sectional study was conducted between March and September 2024 in Gdansk, Poland. Samples from tourniquets used in the emergency department and the operating theatre were collected after an indefinite period, 14 days, and 28 days. Bacterial contamination on the surfaces of the tourniquets was measured using Columbia agar blood medium and expressed as colony-forming units (CFUs) per cm².

Results: Significant bacterial loads were detected on reusable tourniquets, with contamination levels varying by location and duration of use. The average number of CFU/cm² across all stages of this study was 545 CFU/cm² for the emergency department and 101 CFU/cm² for the operating theatre. Tourniquets used in the emergency department exhibited higher bacterial counts compared to those from the operating theatre, which showed a greater diversity of bacterial species. These findings underscore the need to revise infection control protocols for reusable tourniquets.

Conclusion: This study provides critical data that may influence future policy changes aimed at reducing the risk of HAIs through the improved management of reusable medical devices.

ε-poly-l-lysine (ε-PL), a natural food preservative, has garnered widespread attention. It is mainly produced by Streptomyces albulus, but the production by wild-type strains fails to meet the demands of industrialization. To address this issue, adaptive laboratory evolution (ALE) was successfully employed in this study, subjecting S. albulus CICC 11022 to environmental stresses such as acidic pH and antibiotics (rifampicin, gentamicin, and streptomycin). As a result of ALE, an evolutionary strain S. albulus C214 was obtained, exhibiting an increase in ε-PL production and cell growth by 153.23% and 234.51%, respectively, as compared with the original strain. Genomic and metabolic analyses revealed that mutations occurred in genes responsible for transcriptional regulation, transporter, cell envelope, energy metabolism, and secondary metabolite synthesis, as well as the enrichment of metabolites involved in the biosynthesis of ε-PL. These findings hold great significance for elucidating the mechanism underlying ε-PL synthesis.

Vairimorpha (Nosema) ceranae is a pathogen that affects Apis mellifera and Apis ceranae Fabricius, capable of spreading within and between honeybee colonies. The spore wall of microsporidia is the initial structure to contact the host cell directly, which may play a crucial role in the infection process. Currently, several spore wall proteins have been identified in microsporidia, but only two spore wall proteins from V. ceranae have been characterized. Here, we report the expression and identification of a novel spore wall protein, NcSWP8, with a molecular mass of 21.37 kDa in V. ceranae. Subcellular localization analysis revealed that NcSWP8 was localized on the spore wall of V. ceranae. Co-immunoprecipitation and Far-Western blotting experiments demonstrated that NcSWP8 could stably interact with polar tube proteins, NcPTP2 and NcPTP3. The antibody blocking assay significantly decreased their infection rate, indicating that NcSWP8 played a significant role in the process of V. ceranae infection. These results together suggested that NcSWP8 was a new spore wall protein localized to the spore wall and interacted with the polar tube proteins, playing a crucial role in supporting the formation of the spore wall and potentially affecting the process of infection of V. ceranae.

Climate changes and human-related activities are identified as major factors responsible for the increasing distribution and abundance of vectors worldwide and, consequently, of vector-borne diseases (VBDs). Farmed animals, during grazing or in establishments with the absence of biosecurity measures, can easily be exposed to wildlife showing high-risk of contagion of several infectious diseases, including VBDs. Furthermore, livestock represents an interface between wildlife and humans, and thus, promoting the transmission pathway of VBDs. Little is known about the presence and prevalence of VBDs in livestock in Southern Italy; therefore, the present study evaluated the circulation of zoonotic VBDs in livestock and potential risk of exposure. A total of 621 whole blood samples belonging to cattle and buffaloes (n = 345) and small ruminants (n = 276) were examined by molecular examinations for the detection of tick-borne pathogens (TBPs). High prevalence (66.3%) for at least one agent was observed. Moreover, the risk of exposure related to environmental features was assessed, as follows: presence of humid areas, high-density of animals, and sample collection during May. These results show a high circulation of TBPs among livestock and underline the need for surveillance in high-risk habitats for public health.

Respiratory Syncytial Virus (RSV) is a prevalent pathogen of the respiratory tract, posing a significant threat to individuals with compromised immune systems, particularly the elderly and neonates in hospital settings. The primary objective of this study was to identify a specific period within the epidemic season during which healthcare providers can anticipate an increased incidence of RSV infections and characterize the epidemic season in Poland. Molecular biology techniques were employed to diagnose samples at Sanitary Stations and the National Institute of Public Health (NIC) in Warsaw. Epidemiological data were collected using the SENTINEL surveillance system. In the 2020/2021 season, there were no reported cases of RSV due to the prioritization of SARS-CoV-2 diagnostics. Before the pandemic, the period of heightened RSV infection risk typically commenced in the 51st week or later, with a statistically significant correlation indicating that a later start was associated with a shorter season duration (p = 0.034). In post-pandemic seasons, the temporal distribution of RSV cases exhibited a notable shift, with earlier season onset, peak, and conclusion. Data indicate that RSV is predominantly diagnosed in pediatric populations; however, since the 2017/2018 season, there has been an increase in RSV diagnoses among other age groups. Given the observed shifts in the seasonal peak following the SARS-CoV-2 pandemic, ongoing surveillance is required to ascertain whether these changes are permanent or transient.

As an important cereal and feed crop, oat has significant economic value and is widely cultivated throughout the world. However, leaf diseases have become a crucial factor limiting the increase in oat grain yield and the optimization of its nutritional quality. Among these, the bacterial leaf blight disease (LBD) caused by Pantoea agglomerans has been an emerging and prevalent oat disease in Northwest China in recent years and has become a major challenge for oat cultivation in this region. This study was designed to investigate the effects of LBD on grain yield and nutritional quality of two common oat varieties, i.e., Avena nuda "Baiyan 2" (B2) and A. sativa "Baiyan 7" (B7), in greenhouses. The results showed that after infection causing LBD, the growth, grain yield and nutritional indexes (except the fiber content) of B2 and B7 were significantly reduced (p < 0.05), with grains per spike, thousand grain weight, protein, and β-glucan reduced by 14.2%, 5.5%, 12.9% and 21.5%, respectively. In contrast, the average fiber content of the infected oats increased by 8.4%. In addition, both with and without infection, the grain yield of B7 was higher than that of B2, while the nutritional quality of B2 seeds was superior to that of B7 seeds. This study provides a scientific basis for LBD control and the variety selection of oat, promoting the sustainable development of the oat industry.

Grazing intensity is one of the crucial anthropogenic activities on alpine grasslands. However, how grazing intensity affects soil microorganism diversities and their co-occurrence networks in alpine steppe remains uncertain. We carried out a controlled grazing experiment (null grazing, CK; moderate grazing, MG; and heavy grazing, HG) on a typical alpine steppe in the Lhasa River Basin, Central Tibet, China. We used high-throughput sequencing to find the sequences of bacterial 16S rRNA and fungal ITS gene amplicons. Then, we analyzed their alpha and beta diversities and set up co-occurrence networks that show how often they occur together. MG significantly increased the bacterial Shannon index and changed the bacterial community structure. In contrast, HG decreased the fungal ACE and Chao1 indices and also changed the fungal community structure (p < 0.05). Linear mixed-effect model revealed that available phosphorus in soil significantly impacted on soil bacterial Shannon, ACE, and Chao1 indices across grazing intensities, while total carbon in subsoil significantly affected these indicators of soil fungi. Moreover, MG increased the complexity of the co-occurrence network in the bacterial community, while HG simplified it. However, both MG and HG made the co-occurrence networks in the fungal community less complicated. This shows that the intensity of grazing has different impacts on how microbes interact with each other. Therefore, sustainable grazing intensity necessitates a deeper understanding of biodiversity conservation in alpine grasslands.

This systematic review evaluated the effectiveness and side effects of various COVID-19 vaccines, with a focus on Trinidad and Tobago. The Pfizer-BioNTech and Moderna vaccines demonstrated the highest efficacy, particularly against COVID-19 variants, while Janssen and Sinopharm were comparatively less effective. mRNA vaccines, such as Pfizer-BioNTech and Oxford-AstraZeneca, were associated with more frequent and severe side effects, including soreness, fever, and cardiovascular issues. The review also identified significant gaps in the current scientific literature regarding COVID-19 vaccination issues in Trinidad and Tobago. These gaps highlight the need for comprehensive research to address vaccination challenges, including public health communication, equitable access, and local perceptions of vaccine safety. This analysis provides a foundation for developing targeted strategies to improve vaccine effectiveness in the region.

Pyogenic liver abscesses (PLAs) are serious infections in which doctors often fail in identifying the causative agent due to microbiological limitations. These limitations in detecting uncommon pathogens complicate the treatment and recovery. Molecular techniques, like massive sequencing, enable the detection of uncommon pathogens and highlight the shortcomings of traditional cultures. The aim of this work was to characterise the bacterial composition of PLAs through massive sequencing of the V3-V4 hypervariable region of the 16S rRNA gene in cases where conventional culture methods were negative. Purulent material was collected from three patients with PLAs at Hospital Juárez de México. Classical and molecular microbiological cultures were performed in parallel. Metagenomic DNA was extracted and massively sequenced (16S rRNA gene) using the Illumina MiSeq platform. A bioinformatic analysis was performed to determine the diversity at six different taxa levels and the relative abundances. The culture methods were not sufficient to detect the causative agent of the PLAs. However, the massive sequencing revealed the causative agents of the monomicrobial and polymicrobial infectious foci, with Gardnerella vaginalis, Lactobacillus iners, and Prevotella timonensis as the dominant bacteria. The massive sequencing revealed the presence of unusual pathogens that traditional culture failed to detect. There is an immediate need for molecular or comprehensive microbiological culture techniques to search for unusual bacteria in the diagnosis of PLAs.

A comprehensive pharmacovigilance surveillance on antibacterials is lacking. This study aims to investigate safety signals of antibacterial-related adverse drug events (ADEs) with seriousness and to identify predictors of serious ADEs. This study investigated 52,503 antibacterial-induced ADEs reported to the Korea Adverse Event Reporting System Database from January 2013 to December 2022. Disproportionality analysis was conducted, and the effect sizes were estimated by reporting odds ratios (ROR), proportional reporting ratio (PRR), and information component (IC). Multivariate logistic regression was performed to investigate the predictors of serious ADEs by estimating the odds ratio (OR). Serious events were more likely to be cardiovascular disorders (ROR 6.77, PRR 6.6, IC 2.37), urinary system disorders (ROR 5.56, PRR 5.22, IC 2.12), and platelet, bleeding, and clotting disorders (ROR 5.41, PRR 5.17, IC 2.06). The predictors may include age (OR 1.05), the number of concomitant medications (OR 1.44), concomitant proton pump inhibitors (OR 1.46) and non-steroidal anti-inflammatory drugs (OR 1.38) use, and specific antibacterial classes, while multiple antibacterial therapy was associated with lower serious ADE risks. The sensitivity analysis also suggests the male sex (OR 1.18) as a potential predictor of serious ADEs. However, further studies are imperative to determine the causality of antibacterial-induced ADEs in critically ill patients.