Occurrence and characterization of plasmid-encoded qnr genes in quinolone-resistant bacteria across diverse aquatic environments in southern Ontario.

Antimicrobial resistance is an ever-increasing threat. The widespread usage of ciprofloxacin has led to the manifestation of resistance due to chromosomal mutations or the acquisition of plasmid-mediated quinolone resistance (PMQR) traits. Some particular PMQR traits, qnr genes, have been identified globally in clinical and environmental isolates. This study aimed to determine the prevalence of ciprofloxacin-resistant bacteria in aquatic environments in southern Ontario and investigate the extent of dissemination of ciprofloxacin resistance traits among the bacterial communities. We surveyed the prevalence of plasmid encoding qnr genes using a multiplex PCR assay of associated PMQR genes, qnrA, qnrB, and qnrS, on 202 isolates. Despite the absence of significant impacts on minimum inhibitory concentration levels, the presence of qnr genes correlates with heightened resistance to quinolones and nalidixic acid in some isolates. Taxonomic analysis highlights distinct differences in the composition and diversity of ciprofloxacin-sensitive (CipS) and ciprofloxacin-resistant (CipR) populations, with Proteobacteria dominating both groups. Importantly, CipR populations exhibit lower genetic diversity but higher prevalence of multiple antibiotic resistances, suggesting co-selection mechanisms. Co-occurrence analysis highlights significant associations between ciprofloxacin resistance and other antibiotic resistances, implicating complex genetic linkages. The results of our study signified the critical role of environmental monitoring in public health.

Targeted action to increase inclusion at the Wellcome Sanger Institute.

The Sanger Excellence Fellowship has been established to increase the representation of researchers with Black-heritage backgrounds at a leading research centre in the UK.

Role of Mitochondrial Iron Overload in Mediating Cell Death in H9c2 Cells.

Iron overload (IO) is associated with cardiovascular diseases, including heart failure. Our study's aim was to examine the mechanism by which IO triggers cell death in H9c2 cells. IO caused accumulation of intracellular and mitochondrial iron as shown by the use of iron-binding fluorescent reporters, FerroOrange and MitoFerroFluor. Expression of cytosolic and mitochondrial isoforms of Ferritin was also induced by IO. IO-induced iron accumulation and cellular ROS was rapid and temporally linked. ROS accumulation was detected in the cytosol and mitochondrial compartments with CellROX, DCF-DA and MitoSOX fluorescent dyes and partly reversed by the general antioxidant N-acetyl cysteine or the mitochondrial antioxidant SkQ1. Antioxidants also reduced the downstream activation of apoptosis and lytic cell death quantified by Caspase 3 cleavage/activation, mitochondrial Cytochrome c release, Annexin V/Propidium iodide staining and LDH release of IO-treated cells. Finally, overexpression of MitoNEET, an outer mitochondrial membrane protein involved in the transfer of Fe-S clusters between mitochondrial and cytosol, was observed to lower iron and ROS accumulation in the mitochondria. These alterations were correlated with reduced IO-induced cell death by apoptosis in MitoNEET-overexpressing cells. In conclusion, IO mediates H9c2 cell death by causing mitochondrial iron accumulation and subsequent general and mitochondrial ROS upregulation.

Role of low-density lipoprotein receptor rs5925 (1959C>T) gene polymorphism in pathogenesis of dyslipidemia among Egyptian lupus nephritis patients.

Objectives: This study aims to investigate the prevalence of low-density lipoprotein receptor (LDL-R) rs5925 genetic variants and to evaluate their relationship with plasma lipid and kidney functions in lupus nephritis patients. Patients and methods: Between September 2020 and June 2021, a total of 100 lupus nephritis patients (8 males, 92 females; mean age: 31.1±1.1 years; range, 20 to 67 years) and a total of 100 age- and sex-matched healthy volunteers (10 males, 90 females; mean age: 35.8±2.8 years; range, 21 to 65 years) were included. The gene polymorphism rs5925 (LDLR) was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Lipid profile and kidney functions were measured. Results: Regarding rs5925 (LDLR), C allele was significantly higher among lupus nephritis patients (60%) compared to the control group (45%). While T allele was significantly lower in lupus nephritis patients (40%), compared to the control group (p=0.003). The plasma level of total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were significantly lower in lupus nephritis patients with TT and CT genotypes, compared to those with CC genotype. Moreover, atherogenic index of plasma (AIP) and LDL-C/high-density lipoprotein cholesterol (HDL-C) ratio were significantly lower in patients with TT genotype, compared to the patients with CC genotype. There was a strong and clear association between patients with renal biopsies grades III & IV & V and LDLR C allele (p=0.01, p=0.003, and p=0.004, respectively). Conclusion: C allele is the significantly prevailed LDLR C1959T variant among lupus nephritis patients. Moreover, LDL-R genetic variant may be one of the non-immunological mechanisms implicated in the disturbed lipid profile among lupus nephritis patients. Profound dyslipidemia may partly underscore the deterioration of kidney function among lupus nephritis patients.