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BMC Microbiology Jun 2024The incidence of hospital-acquired infections in extensively drug-resistant Pseudomonas aeruginosa (XDR-PA) has been increasing worldwide and is frequently associated...
BACKGROUND
The incidence of hospital-acquired infections in extensively drug-resistant Pseudomonas aeruginosa (XDR-PA) has been increasing worldwide and is frequently associated with an increase in mortality and morbidity rates. The aim of this study was to characterize clinical XDR-PA isolates recovered during six months at three different hospitals in Egypt.
RESULTS
Seventy hospital-acquired clinical isolates of P. aeruginosa were classified into multidrug-resistant (MDR), extensively drug-resistant (XDR) and pandrug-resistant (PDR), according to their antimicrobial resistance profile. In addition, the possession of genes associated with mobile genetic elements and genes encoding antimicrobial resistance determinants among isolates were detected using polymerase chain reaction. As a result, a significant percentage of the isolates (75.7%) were XDR, while 18.5% were MDR, however only 5.7% of the isolates were non-MDR. The phenotypic detection of carbapenemases, extended-spectrum β-lactamases (ESBLs) and metallo β-lactamase (MBL) enzymes showed that 73.6% of XDR-PA isolates were carbapenemases producers, whereas 75.5% and 88.7% of XDR-PA isolates produced ESBLs and MBL respectively. In addition, PCR screening showed that oxa gene was the most frequently detected gene of carbapenemases (91.4%), while aac(6')-lb gene was mostly detected (84.3%) among the screened aminoglycosides-resistance genes. Furthermore, the molecular detection of the colistin resistance gene showed that 12.9% of isolates harbored mcr-1 gene. Concerning mobile genetic element markers (intI, traA, tnp513, and merA), intI was the highest detected gene as it was amplified in 67 isolates (95.7%). Finally, phylogenetic and molecular typing of the isolates via ERIC-PCR analysis revealed 10 different ERIC fingerprints.
CONCLUSION
The present study revealed a high prevalence of XDR-PA in hospital settings which were resistant to a variety of antibiotics due to several mechanisms. In addition, 98% of the XDR-PA clinical isolates contained at least one gene associated with movable genetic elements, which could have aided the evolution of these XDR-PA strains. To reduce spread of drug resistance, judicious use of antimicrobial agents and strict infection control measures are therefore essential.
Topics: Pseudomonas aeruginosa; Humans; Pseudomonas Infections; Drug Resistance, Multiple, Bacterial; Cross Infection; Egypt; beta-Lactamases; Anti-Bacterial Agents; Microbial Sensitivity Tests; Bacterial Proteins; Hospitals; Interspersed Repetitive Sequences; Polymerase Chain Reaction
PubMed: 38926687
DOI: 10.1186/s12866-024-03321-5 -
The British Journal of Ophthalmology Jun 2024To report an epidemiological update of bacterial keratitis (BK) in a tertiary ophthalmology centre over 20 months compared with a previous study on the same timeframe...
AIMS
To report an epidemiological update of bacterial keratitis (BK) in a tertiary ophthalmology centre over 20 months compared with a previous study on the same timeframe from 1998 to 1999.
METHODS
354 patients with BK documented by microbiological corneal scraping or resolutive under antibiotics treatment from January 2020 to September 2021 were analysed retrospectively.
RESULTS
One or several risk factors were found in 95.2% of patients: contact lens wear (45.2%), ocular surface disease (25.0%), systemic disease (21.8%), ocular trauma (11.9%) and ocular surgery (8.8%). The positivity rate of corneal scrapings was 82.5%, with 18.2% polybacterial. One hundred seventy-five (59.9%) bacteria were Gram-negative, and 117 (40.1%) were Gram-positive. The most common bacteria were (32.5%), spp (18.1%) and (8.2%). Final visual acuity (logarithm of the minimum angle of resolution) was associated with age (r=+0.48; p=0.0001), infiltrate size (r=+0.32; p<0.0001), ocular surface disease (r=+0.13; p=0.03), ocular trauma (r=-0.14; p=0.02) and contact lens wear (r=-0.26; p<0.0001). Gram-negative bacteria were responsible for deeper (r=+0.18; p=0.004) and more extensive infiltrates (r=+0.18; p=0.004) in younger patients (r=-0.19; p=0.003). Compared with the previous period, the positivity rate of corneal scrapings and the proportion of Gram-negative bacteria, especially spp, increased. All and spp were sensitive to quinolones, and all were sensitive to both quinolones and methicillin.
CONCLUSION
Contact lens wear remained the leading risk factor. The bacteria distribution was reversed, with a predominance of Gram-negative bacteria and increased spp.
PubMed: 38925906
DOI: 10.1136/bjo-2024-325261 -
European Respiratory Review : An... Apr 2024Neuroimmune recognition and regulation in the respiratory system is a complex and highly coordinated process involving interactions between the nervous and immune... (Review)
Review
Neuroimmune recognition and regulation in the respiratory system is a complex and highly coordinated process involving interactions between the nervous and immune systems to detect and respond to pathogens, pollutants and other potential hazards in the respiratory tract. This interaction helps maintain the health and integrity of the respiratory system. Therefore, understanding the complex interactions between the respiratory nervous system and immune system is critical to maintaining lung health and developing treatments for respiratory diseases. In this review, we summarise the projection distribution of different types of neurons (trigeminal nerve, glossopharyngeal nerve, vagus nerve, spinal dorsal root nerve, sympathetic nerve) in the respiratory tract. We also introduce several types of cells in the respiratory epithelium that closely interact with nerves (pulmonary neuroendocrine cells, brush cells, solitary chemosensory cells and tastebuds). These cells are primarily located at key positions in the respiratory tract, where nerves project to them, forming neuroepithelial recognition units, thus enhancing the ability of neural recognition. Furthermore, we summarise the roles played by these different neurons in sensing or responding to specific pathogens (influenza, severe acute respiratory syndrome coronavirus 2, respiratory syncytial virus, human metapneumovirus, herpes viruses, Sendai parainfluenza virus, , , , amoebae), allergens, atmospheric pollutants (smoking, exhaust pollution), and their potential roles in regulating interactions among different pathogens. We also summarise the prospects of bioelectronic medicine as a third therapeutic approach following drugs and surgery, as well as the potential mechanisms of meditation breathing as an adjunct therapy.
Topics: Humans; Animals; Neuroimmunomodulation; Respiratory System; Host-Pathogen Interactions; Respiratory Tract Diseases; Signal Transduction
PubMed: 38925790
DOI: 10.1183/16000617.0008-2024 -
International Ophthalmology Jun 2024To provide a comprehensive microbiological profile of bacterial dacryocystitis in South Australia. By identifying the specific microorganism and antibiotic...
PURPOSE
To provide a comprehensive microbiological profile of bacterial dacryocystitis in South Australia. By identifying the specific microorganism and antibiotic susceptibility, this study intends to aid ophthalmologists in choosing appropriate empirical antibiotic therapies and development of evidence-based clinical guidelines.
METHOD
A retrospective study was conducted at the Royal Adelaide Hospital (RAH) over five years (2018-2023) of patients with acute dacryocystitis. The study included 43 patients, and data encompassed demographic information, clinical presentation, microbiological analysis, management, and outcomes. Patients with chronic dacryocystitis were excluded.
RESULTS
Among the 43 patients included in the study (female 28 (65%), mean age: 64 years old), the most common clinical features were pain (74%) and swelling (70%). Organisms were identified in 49% of patients, with the predominant bacteria being Staphylococcus aureus (42%), Streptococcus species (19%), and Escherichia coli (8%). Aggregatibacter species (8%), Morganella morganii (4%), Enterobacter cloaceae (4%), Hafnia alvei (4%), mixed anaerobes (4%), E coliforms (4%) and Pseudomonas aeruginosa (4%) were also identified. The most frequently prescribed empirical antibiotics were amoxicillin-clavulanic acid (50%), flucloxacillin (33%) and cefalexin (18%).
CONCLUSION
The microbiological trends of acute dacryocystitis have largely remained consistent, with a predominance of Gram positive organisms. This is the most recent profile analysis of acute dacryocystitis in South Australia and will help form evidence-based clinical guidelines.
Topics: Humans; Female; Middle Aged; Dacryocystitis; Male; Eye Infections, Bacterial; Retrospective Studies; South Australia; Acute Disease; Anti-Bacterial Agents; Aged; Tertiary Care Centers; Adult; Bacteria; Microbial Sensitivity Tests; Aged, 80 and over
PubMed: 38922457
DOI: 10.1007/s10792-024-03236-0 -
Anais Da Academia Brasileira de Ciencias 2024I. paraguariensis St. Hil. is a south American species of agronomic interest with studies supporting its medicinal properties. As the investigation of active ingredients...
I. paraguariensis St. Hil. is a south American species of agronomic interest with studies supporting its medicinal properties. As the investigation of active ingredients with antimicrobial effect from medicinal plants is a suitable approach to the current antibacterial resistance problem, the aim of the present study was to determine the antibacterial activity of yerba mate ethanolic extracts against carbapenemase-producing gram-negative bacteria (reference strains and clinical isolates). Extracts showed antibacterial activity against Klebsiella pneumoniae ATCC® BAA-2342™ (KPC producing), Providencia rettgeri (NDM producing), Pseudomonas aeruginosa (MBL producing) and P. aeruginosa (VIM producing) at the concentrations tested. The Minimal-Inhibitory-Concentration and Minimal-Bactericidal-Concentration values ranged between 1 and 32 mg.ml-1 for the reference strains, and between 0.125 and 1 mg.ml-1 for the clinical isolates. The MBC/MIC index characterized the extracts as bactericidal. The combinations of commercial antibiotics and extracts showed a synergistic action on the reference strains studied. The lethal concentration 50 obtained using the Artemia salina toxicity assay were higher than 1 mg.ml-1 for all the extracts, indicating a low toxicity. The in vitro activity and low toxicity suggest that ethanolic I. paraguariensis leaf extracts constitute an outstanding source for new antibacterial compounds, and further studies should be carried out to understand their mechanism of action.
Topics: Plant Extracts; Ilex paraguariensis; beta-Lactamases; Microbial Sensitivity Tests; Plant Leaves; Anti-Bacterial Agents; Gram-Negative Bacteria; Bacterial Proteins; Pseudomonas aeruginosa; Animals; Klebsiella pneumoniae
PubMed: 38922267
DOI: 10.1590/0001-3765202420221129 -
Toxins Jun 2024Extensively drug-resistant infections are emerging as a significant threat associated with adverse patient outcomes. Due to this organism's inherent properties of...
Extensively drug-resistant infections are emerging as a significant threat associated with adverse patient outcomes. Due to this organism's inherent properties of developing antibiotic resistance, we sought to investigate alternative strategies such as identifying "high value" antigens for immunotherapy-based purposes. Through extensive database mining, we discovered that numerous Gram-negative bacterial (GNB) genomes, many of which are known multidrug-resistant (MDR) pathogens, including , horizontally acquired the evolutionarily conserved gene encoding Zonula occludens toxin (Zot) with a substantial degree of homology. The toxin's genomic footprint among so many different GNB stresses its evolutionary importance. By employing in silico techniques such as proteomic-based phylogenetic tracing, in conjunction with comparative structural modeling, we discovered a highly conserved intermembrane associated stretch of 70 amino acids shared among all the GNB strains analyzed. The characterization of our newly identified antigen reveals it to be a "high value" vaccine candidate specific for . This newly identified antigen harbors multiple non-overlapping B- and T-cell epitopes exhibiting very high binding affinities and can adopt identical tertiary structures among the least genetically homologous strains. Taken together, using proteomic-driven reverse vaccinology techniques, we identified multiple "high value" vaccine candidates capable of eliciting a polarized immune response against all the genetic variants tested.
Topics: Pseudomonas aeruginosa; Phylogeny; Pseudomonas Infections; Humans; Epitopes, T-Lymphocyte; Pseudomonas Vaccines; Epitopes, B-Lymphocyte
PubMed: 38922165
DOI: 10.3390/toxins16060271 -
Toxics Jun 2024This study utilizes (MI) for the first time to investigate the uptake and translocation of chlorpyrifos (CPF; 10 µg g) from soil, introducing a new approach to improve...
This study utilizes (MI) for the first time to investigate the uptake and translocation of chlorpyrifos (CPF; 10 µg g) from soil, introducing a new approach to improve the efficacy of this technique, which includes using biosurfactants ( and ) at 10 CFU/mL to degrade CPF under greenhouse conditions. Moreover, antioxidant enzymes, including superoxide dismutase (SOD) and peroxidase (Prx), and oxidative stress due to hydrogen peroxide (HO) and malondialdehyde (MDA) in MI roots and leaves were evaluated under CPF stress. Our results demonstrated that amending soil with MI and followed by significantly reduced CPF levels in the soil ( > 0.05) and enhanced CPF concentrations in MI roots and leaves after 1, 3, 7, 10, and 14 days of the experiment. Furthermore, CPF showed its longest half-life (t) in soil contaminated solely with CPF, lasting 15.36 days. Conversely, its shortest half-life occurred in soil contaminated with CPF and treated with MI along with , lasting 4.65 days. Soil contaminated with CPF and treated with MI and showed a half-life of 7.98 days. The half-life (t) of CPF-contaminated soil with MI alone was 11.41 days. A batch equilibrium technique showed that is better than for eliminating CPF from soil in In vitro experiments. Notably, CPF-polluted soil treated with coadministration of MI and the tested bacteria improved the activities of SOD and Prx and reduced HO and MDA compared with CPF-polluted soil treated with MI alone. Our findings demonstrated that using and as biosurfactants to augment phytoremediation represents a commendable strategy for enhancing the remediation of CPF contamination in affected sites while reducing the existence of harmful pesticide remnants in crop plants.
PubMed: 38922115
DOI: 10.3390/toxics12060435 -
Veterinary Sciences May 2024The direct effects and antimicrobial activity of synthetic antimicrobial peptides (AMPs) obtained from dogs, including cBD, cBD103, and cCath, against wild-type strain...
The direct effects and antimicrobial activity of synthetic antimicrobial peptides (AMPs) obtained from dogs, including cBD, cBD103, and cCath, against wild-type strain PAO1 and canine keratinocytes were analyzed. Antibacterial effects on planktonic bacteria were assessed by determining the minimum bactericidal concentrations (MBCs) of AMPs and by a time-kill assay. Antibiofilm effects were assessed using the microtiter plate assay. We also evaluated the effects of AMPs on cell cytotoxicity and host immune response induced by stimulating canine epidermal keratinocyte progenitor (CPEK) cells with PAO1 and its LPS. cBD, cBD103, and cCath all exhibited dose-dependent antimicrobial and antibiofilm effects. In particular, 25 μg/mL cBD103 showed rapid bactericidal activity within 60 min and inhibited biofilm formation. In addition, pretreatment with cBD103 (25 µg/mL) and cCath (50 µg/mL) 1 h before stimulation significantly reduced the cytotoxicity of the CPEK cells by PAO1 and LPS-induced IL-6 and TNF-a expressions. cBD had little effect on the response to PAO1 and LPS in the cells. These results indicate the therapeutic potential of AMPs in skin infections. However, further studies on the mechanism of action of AMPs in keratinocytes and clinical trials are needed.
PubMed: 38921982
DOI: 10.3390/vetsci11060235 -
Nanomaterials (Basel, Switzerland) Jun 2024Tetrahedral amorphous carbon (taC) is a hydrogen-free carbon with extensive properties such as hardness, optical transparency, and chemical inertness. taC coatings have...
Tetrahedral amorphous carbon (taC) is a hydrogen-free carbon with extensive properties such as hardness, optical transparency, and chemical inertness. taC coatings have attracted much attention in recent times, as have coatings doped with a noble metal. A known antimicrobial metal agent, silver (Ag), has been used as a dopant in taC, with different Ag concentrations on the Ti64 coupons using a hybrid filtered cathodic vacuum arc (FCVA) and magnetron sputtering system. The physiochemical properties of the coated surface were investigated using spectroscopic and electron microscopy techniques. A doping effect of Ag-taC on biofilm formation was investigated and found to have a significant effect on the bacterial-biofilm-forming bacteria and depending on the concentration of Ag. Further, the effect of coated and uncoated Ag-taC films on a pathogenic bacterium was examined using SEM. The result revealed that the Ag-taC coatings inhibited the biofilm formation of . Therefore, this study demonstrated the possible use of Ag-taC coatings against biofilm-related complications on medical devices and infections from pathogenic bacteria.
PubMed: 38921893
DOI: 10.3390/nano14121017 -
Pathogens (Basel, Switzerland) Jun 2024is a common pathogen associated with recreational water facilities and poses risks to public health. However, data on the prevalence of in tourist destinations like...
is a common pathogen associated with recreational water facilities and poses risks to public health. However, data on the prevalence of in tourist destinations like the Canary Islands, Spain, remain limited. We assessed prevalence in 23 tourist facilities from 2016 to 2019. Compliance with water quality standards was evaluated, and 3962 samples were collected and analyzed. We examined different types of recreational water installations, including outer swimming pools, whirlpools, and cold wells. Of the sampled facilities, 31.2% did not comply with the current legislation's parametric values, mainly due to inadequate disinfectant levels, water temperature, and presence. The prevalence of was 4.8%, comparable to some European countries but lower than others. Cold wells displayed the highest non-compliance rate (89.2%) and yet exhibited a lower prevalence (1.9%) than outer swimming pools and whirlpools. Children's presence did not significantly impact contamination. Chlorine-based disinfectants are more effective than bromine-based ones in controlling . Regional variability in contamination was observed, with Fuerteventura showing lower colonization rates. Disinfectant levels play a critical role in control, and maintaining adequate levels is essential, particularly in bromine-treated installations. Our findings provide valuable insights into the prevalence and distribution of in recreational waters within tourist facilities. Tailored strategies are needed to ensure water safety in different Spanish regions. Continued monitoring and assessment, combined with artificial intelligence and machine learning, will enable the implementation of targeted interventions to protect the health of recreational water users.
PubMed: 38921799
DOI: 10.3390/pathogens13060501