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The hollow-fibre infection model (HFIM) is a valuable in vitro platform for emulating antimicrobial drug pharmacokinetic profiles. Despite its potential, standardized protocols for HFIM operation, especially concerning fastidious organisms, are lacking. This study addresses this gap by examining challenges in culturing Pasteurella multocida and Actinobacillus pleuropneumoniae, two fastidious organisms, in the HFIM. Our findings reveal effective strategies to prevent system clogging, involving multiple freeze-thaw cycles of horse blood, centrifugation and cell straining to enhance the clarity of the Mueller-Hinton fastidious medium defined by the European Committee on Antimicrobial Susceptibility Testing and Clinical and Laboratory Standards Institute. Additionally, we propose that the provision of a CO₂ atmosphere, along with the utilization of gas-permeable tubing and gas vent filters, significantly facilitates the growth of fastidious organisms. Remarkably, both P. multocida and A. pleuropneumoniae were sustained for a period of up to 10 days under these optimized conditions. This study provides crucial insights into the modifications necessary to successfully culture fastidious organisms in the HFIM, paving the way for more accurate and representative in vitro models for antimicrobial drug testing. These advancements hold promise for advancing research in the field of antimicrobial pharmacokinetics and efficacy against challenging pathogens.

Group A streptococcus (GAS) can cause serious invasive disease in humans with a high mortality rate. An increase in GAS infections was reported in Ireland in 2022, and this increase has been sustained in 2023 and is paralleled by similar trends in Europe. Rising antimicrobial resistance is a global problem and presents significant challenges to clinicians treating GAS infection. There was a reported increase in clindamycin resistance in GAS isolates in Ireland in 2022. We examined antimicrobial susceptibility patterns of GAS isolates in our institution in 2022. Although all GAS isolates included in our study were susceptible to penicillin, we noted a high clindamycin resistance rate of 28 % in our invasive GAS isolates. We also noted high tetracycline and erythromycin resistance, 43 and 30 %, respectively. Our results could have implications for empiric antimicrobial prescribing guidelines for skin and soft tissue infections, which often include clindamycin as it inhibits the production of many virulence factors associated with GAS. In addition, macrolides are often the first line recommended antibiotic for patients with anaphylaxis to penicillin. This study emphasises the importance of continuous surveillance and antimicrobial susceptibility testing of invasive and non-invasive isolates in order to monitor trends in increasing antimicrobial resistance.

Listeriosis constitutes a significant public health threat due to its high mortality rate. This study investigates the microbiological and genomic characteristics of Listeria monocytogenes isolates in Madagascar, where listeriosis is a notifiable disease. The analysis focuses on a fatal case of meningeal listeriosis in a 12-year-old child. Genomic analysis revealed a novel cgMLST type (L2-SL8-ST8-CT11697; CC8, serogroup Iia) with typical virulence and antibiotic resistance profiles. These isolates, unique to Madagascar, formed an independent clade in the phylogenetic tree. This study presents the first genomic characterization of Listeria isolates in Madagascar, highlighting the necessity of ongoing genomic surveillance to strengthen listeriosis prevention and control strategies in the region.

Objectives. Staphylococcus aureus is one of the most common pathogens attributed to hospital infections. Although S. aureus infections have been well studied in developed countries, far less is known about the biology of the pathogen in sub-Saharan Africa. Methods. Here, we report on the isolation, antibiotic resistance profiling, whole genome sequencing, and genome comparison of six multi-drug resistant isolates of S. aureus obtained from a referral hospital in Kakamega, Western Kenya. Results. Five of the six isolates contained a 20.7 kb circular plasmid carrying blaZ (associated with resistance to β-lactam antibiotics). These five strains all belonged to the same sequence type, ST152. Despite the similarity of the plasmid in these isolates, whole genome sequencing revealed that the strains differed, depending on whether they were associated with hospital-acquired or community-acquired infections. Conclusion. The intriguing finding is that the hospital-acquired and the community-acquired isolates of S. aureus belonging to the same genotype, ST152, formed two separate sub-clusters in the phylogenetic tree and differed by the repertoire of accessory virulence genes. These data suggest ongoing adaptive evolution and significant genomic plasticity.

The ethanolic (80 %), methanolic (80 %) and aqueous decoction (100 % distilled water) of whole plant of Oxalis corniculata Linn (Indian Sorrel) was evaluated for its anti-microbial and antioxidant properties by in vitro methods. Methanolic (80 %) and ethanolic (80 %) decoctions showed significant antibacterial property against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Salmonella typhi bacterial strains. In comparison to Chloramphenicol (C30) against bacteria, 80 % ethanolic decoctions showed significant effect, among the decoctions. Nowadays though the standard soap is in huge demand but it's also facing major backlash due to the presence of synthetic compounds in it, which over long use may cause harmful effects on the skin health. Therefore, the organic soaps which are made up of natural ingredients, herbs or any sort Ayurvedic compound have fewer side effects on the human skin and are much safer than standard daily soap. The formulated therapeutic soap exhibits a significant amount of reducing potential (high FRAP and TAC values) and antioxidant activity (DPPH, ABTS assay).

Background and purpose. Coronavirus (COVID-19) is a contagious disease causing severe acute respiratory syndrome which had a catastrophic effect on the world population and resulted in more than 2.9 million deaths worldwide. Epidemiological investigations have recently announced blood type has an association with the incidence of COVID-19 infection. Consequently, research in this regard can be effective in determining a person's susceptibility to a viral infection. Therefore, we investigated the relationship between blood types and the risk of COVID-19 in patients admitted to Khorshid laboratory, Tehran, Iran. Materials and methods. From January to March 2020, 50 nasal and throat swapb samples of patients' secretions were obtained from patients who were admitted to Khorshid laboratory. They were confirmed to have COVID-19 virus RNA and real-time polymerase chain reaction (PCR)-ABI, and their blood type was determined simultaneously. After collecting data to determine the relationship between COVID-19 infection and blood type, a confidence interval of 90 % was considered using SPSS 16. Results. The mean age of the patients was measured at 38.4±6.3 years. According to PCR results, 100 % of the subjects with COVID-19 showed blood type A. In addition, the ratio of blood type A to the percentage of reference type O was higher (P=0.009). Conclusion. There was a significant relationship between ABO blood type and susceptibility to COVID-19. As the current study suggests, those with blood type A are at a higher COVID-19 infection risk than those with blood type O.

West Nile virus (WNV) is the most prevalent mosquito-borne virus and the leading cause of viral encephalitis in the continental United States. It belongs to the family Flaviviridae which includes other important human pathogens such as dengue virus (DENV), Japanese encephalitis virus (JEV) and Zika viruses (ZIKV). Despite several decades of research, no specific antiviral drugs are available to treat flavivirus infections. The present study characterizes the interaction between the WNV NS3 and NS5 proteins for the purpose of identifying hotspots in the protein-protein interaction which could be targeted for the development of antiviral therapeutics. We previously developed an interaction model in silico based on data available in the literature. Here, potential interacting residues on NS3 and NS5 were mutated in a WNV replicon, and seven mutations in the NS3 protein were found to drastically reduce viral replication. In addition to being well conserved among mosquito-borne flaviviruses, these residues are located on the protein's surface in two clusters which might be interesting new targets for future drug development.

In the past decade, it has become increasingly difficult to engage and encourage critical thinking and deeper learning in students who participate in higher education, particularly in non-major subjects. Photovoice is a participatory action research methodology that has been used in community-based research in many different areas including social science, health science and education. In this study, photovoice was used as a pedagogical tool in a third-year BSc Bioscience non-major microbiology module at Dundalk Institute of Technology. In order to ascertain if photovoice was an effective way of engaging these students, a qualitative descriptive methodological approach, in the form of a focus group, was employed. Six of the 13 students who took the module participated in the focus group, reporting a positive experience overall of using photovoice. Further analysis of the focus group data resulted in the overarching theme of choice, with creativity and critical thinking and research skills as sub-themes to emerge. These findings suggest that photovoice is an effective way to engage students in microbiology as a non-major subject. However, as it was a small sample size, future research would need to use a larger cohort of students to provide further evidence of using photovoice as a pedagogical engagement tool for non-major subjects.

Gymnopus fusipes is an understudied root rot pathogen associated with multiple tree species and is linked to episodes of oak decline across the United Kingdom and Europe. Although the reported distribution of G. fusipes is broad, many observations rely solely on visual identification of fruiting bodies, which can be unreliable, and lack confirmation by molecular and/or isolation data to verify this broad ecological range. Given the paucity of information regarding the true ecological distribution of G. fusipes, it is difficult to predict and model the potential distribution of the species under both current and future climate scenarios. In this study, to determine the growth capabilities of G. fusipes across a range of ecologically relevant temperatures, five geographically diverse isolates of G. fusipes were grown at five different temperatures ranging from 4-37°C, to determine the optimal temperature for G. fusipes growth, and to establish whether geographically diverse isolates exhibit local adaptation to temperature tolerance. Incubation temperature had a significant effect on G. fusipes growth rate, with 25°C representing the optimum (P<0.001). Isolates had differing growth rates at each of the temperatures, with an isolate from the UK having the highest overall growth rate across all five temperatures tested (P<0.001), and at the optimum, increased by a mean value of over 4915 mm². Local adaptation to temperature tolerance was not found in the isolates tested. These data demonstrate the optimal incubation temperature for future laboratory studies on G. fusipes and provide the first data on the growth rate of this pathogen across ecologically relevant climate ranges that may inform land managers, modellers, and policy makers in predicting the current and potentially future geographical limits of this widespread root rot pathogen.