Staphylococcus aureus: Overview of Bacteriology, Clinical Diseases, Epidemiology, Antibiotic Resistance and Therapeutic Approach

Staphylococcus aureus is an important human pathogen that causes wide range of infectious conditions both in nosocomial and community settings. The Gram-positive pathogen is armed with battery of virulence factors that facilitate to establish infections in the hosts. The organism is well known for its ability to acquire resistance to various antibiotic classes. The emergence and spread of methicillin-resistant S. aureus (MRSA) strains which are often multi-drug resistant in hospitals and subsequently in community resulted in significant mortality and morbidity. The epidemiology of MRSA has been evolving since its initial outbreak which necessitates a comprehensive medical approach to tackle this pathogen. Vancomycin has been the drug of choice for years but its utility was challenged by the emergence of resistance. In the last 10 years or so, newer anti-MRSA antibiotics were approved for clinical use. However, being notorious for developing antibiotic resistance, there is a continuous need for exploring novel anti-MRSA agents from various sources including plants and evaluation of non-antibiotic approaches

The potential impact of the COVID-19 pandemic on global antimicrobial and biocide resistance:An AMR Insights global perspective

The COVID-19 pandemic presents a serious public health challenge in all countries. However, repercussions of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections on future global health are still being investigated, including the pandemic's potential effect on the emergence and spread of global antimicrobial resistance (AMR). Critically ill COVID-19 patients may develop severe complications, which may predispose patients to infection with nosocomial bacterial and/or fungal pathogens, requiring the extensive use of antibiotics. However, antibiotics may also be inappropriately used in milder cases of COVID-19 infection. Further, concerns such as increased biocide use, antimicrobial stewardship/infection control, AMR awareness, the need for diagnostics (including rapid and point-of-care diagnostics) and the usefulness of vaccination could all be components shaping the influence of the COVID-19 pandemic. In this publication, the authors present a brief overview of the COVID-19 pandemic and associated issues that could influence the pandemic's effect on global AMR.</p

The potential impact of the COVID-19 pandemic on global antimicrobial and biocide resistance : an AMR Insights global perspective

The COVID-19 pandemic presents a serious public health challenge in all countries. However, repercussions of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections on future global health are still being investigated, including the pandemic’s potential effect on the emergence and spread of global antimicrobial resistance (AMR). Critically ill COVID-19 patients may develop severe complications, which may predispose patients to infection with nosocomial bacterial and/or fungal pathogens, requiring the extensive use of antibiotics. However, antibiotics may also be inappropriately used in milder cases of COVID-19 infection. Further, concerns such as increased biocide use, antimicrobial stewardship/infection control, AMR awareness, the need for diagnostics (including rapid and point-of-care diagnostics) and the usefulness of vaccination could all be components shaping the influence of the COVID-19 pandemic. In this publication, the authors present a brief overview of the COVID-19 pandemic and associated issues that could influence the pandemic’s effect on global AMR.This study was supported by internal funding.https://academic.oup.com/jacamram2022School of Health Systems and Public Health (SHSPH

Refugees in Sweden during the Covid-19 pandemic-the need for a new perspective on health and integration

Refugees are already a vulnerable group in society and are in a stressful situation due to their often uncertain legal status in seeking asylum and integration in the new society after migration. Refugees are, in general, at greater risk of poor health outcomes when contracting Covid-19, exacerbated by poor living conditions and difficulties in accessing healthcare. The longer-term social consequences of the pandemic also disproportionately impact refugees, including social isolation, unemployment and difficulties to obtain correct health information. The aim of this paper is to review the social and health consequences that Covid-19 has brought to the refugees residing in Sweden. This needs to be emphasized in order to mitigate against these likely consequences and improve the overall well-being among such a highly vulnerable group in society. As Covid-19 demonstrates, human health needs to be understood holistically, meaning that the vulnerability of any individuals, or even nations, is a vulnerability for the whole population requiring urgent action.  Keywords: Covid-19, refugees, social situation, health informatio

Approaches to Bacterial RNA Isolation and Purification for Microarray Analysis of Escherichia coli K1 Interaction with Human Brain Microvascular Endothelial Cells

We established a protocol for isolation of microarray-grade bacterial RNA from Escherichia coli K1 interacting with human brain microvascular endothelial cells. The extracted RNA was free of human RNA contamination. More importantly, microarray analysis demonstrated that no bias was introduced in the gene expression pattern during the RNA isolation procedure

Effects of ompA Deletion on Expression of Type 1 Fimbriae in Escherichia coli K1 Strain RS218 and on the Association of E. coli with Human Brain Microvascular Endothelial Cells

We have previously shown that outer membrane protein A (OmpA) and type 1 fimbriae are the bacterial determinants involved in Escherichia coli K1 binding to human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. In investigating the role of OmpA in E. coli K1 binding to HBMEC, we showed for the first time that ompA deletion decreased the expression of type 1 fimbriae in E. coli K1. Decreased expression of type 1 fimbriae in the ompA deletion mutant was largely the result of driving the fim promoter toward the type 1 fimbrial phase-OFF orientation. mRNA levels of fimB and fimE were found to be decreased with the OmpA mutant compared to the parent strain. Of interest, the ompA deletion further decreased the abilities of E. coli K1 to bind to and invade HBMEC under the conditions of fixing type 1 fimbria expression in the phase-ON or phase-OFF status. These findings suggest that the decreased ability of the OmpA mutant to interact with HBMEC is not entirely due to its decreased type 1 fimbrial expression and that OmpA and type 1 fimbriae facilitate the interaction of E. coli K1 with HBMEC at least in an additive manner

Deacetylase activities of rHos2 and dose response curves of rHos2 inhibition by standard HDAC inhibitors: UPDATE 1

<p>Dose response curve of rHos2 enzyme inhibition by MS275: Fluorimetric deacetylase assay with rHos2 protein using Boc-Lys(ac)-AMC substrate in presence of different concentrations of MS-275.</p> <p>Dose response curve of rHos2 enzyme inhibition by SAHA: Fluorimetric deacetylase assay with rHos2 protein using Boc-Lys(ac)-AMC substrate in presence of different concentrations of suberoylanilide hydroxamic acid (SAHA).</p> <p>Dose response curve of rHos2 enzyme inhibition by TSA: Fluorimetric deacetylase assay with rHos2 protein using Boc-Lys(ac)-AMC substrate in presence of different concentrations of trichostatin.</p> <p>rHos2 conc_Enzyme activity: Fluorimetric deacetylase assay with rHos2 protein using Boc-Lys(ac)-AMC substrate. Updated from: http://dx.doi.org/10.6084/m9.figshare.841655</p

NlpI Contributes to Escherichia coli K1 Strain RS218 Interaction with Human Brain Microvascular Endothelial Cells▿

Escherichia coli K1 is the most common Gram-negative bacillary organism causing neonatal meningitis. E. coli K1 binding to and invasion of human brain microvascular endothelial cells (HBMECs) is a prerequisite for its traversal of the blood-brain barrier (BBB) and penetration into the brain. In the present study, we identified NlpI as a novel bacterial determinant contributing to E. coli K1 interaction with HBMECs. The deletion of nlpI did not affect the expression of the known bacterial determinants involved in E. coli K1-HBMEC interaction, such as type 1 fimbriae, flagella, and OmpA, and the contribution of NlpI to HBMECs binding and invasion was independent of those bacterial determinants. Previous reports have shown that the nlpI mutant of E. coli K-12 exhibits growth defect at 42°C at low osmolarity, and its thermosensitive phenotype can be suppressed by a mutation on the spr gene. The nlpI mutant of strain RS218 exhibited similar thermosensitive phenotype, but additional spr mutation did not restore the ability of the nlpI mutant to interact with HBMECs. These findings suggest the decreased ability of the nlpI mutant to interact with HBMECs is not associated with the thermosensitive phenotype. NlpI was determined as an outer membrane-anchored protein in E. coli, and the nlpI mutant was defective in cytosolic phospholipase A2α (cPLA2α) phosphorylation compared to the parent strain. These findings illustrate the first demonstration of NlpI's contribution to E. coli K1 binding to and invasion of HBMECs, and its contribution is likely to involve cPLA2α