Type IV pili (TFPs) serve as the primary receptor for phages in (PA), playing a key role in phage selection and determining the phage host range. We previously demonstrated that a fiersphage (PP7) selectively infects PA strains with group II (G2) TFP pilin. In this study, we expanded on this by profiling the host range of another fiersphage, (LeviOr01), which was able to infect several PA strains including PMM23.
View Article and Find Full Text PDFIncreasing antibiotic resistance of bacterial pathogens poses a serious threat to human health worldwide. Methicillin-resistant Staphylococcus aureus (MRSA) is among the most deleterious bacterial pathogens owing to its multidrug resistance, necessitating the development of new antibacterial agents against it. We previously identified a novel dioxonaphthoimidazolium agent, c5, with moderate antibacterial activity against MRSA from an anticancer clinical candidate, YM155.
View Article and Find Full Text PDFObjective: Second-generation antipsychotics (SGAs) have revolutionized the treatment of psychiatric disorders, but are associated with significant metabolic risks, including diabetes and hyperglycemic crises. This review explores the complex interplay between antipsychotics, diabetes, and hyperglycemic crises, highlighting the mechanisms underlying SGA-induced diabetes.
Methods: We present the case of a patient with schizophrenia who was taking antipsychotic medication and was admitted to the emergency room due to the sudden onset of diabetic ketoacidosis (DKA) without any history of diabetes.
Introduction: Parkinson's disease (PD) is a neurodegenerative disorder characterized by dopaminergic dysfunction and associated with abnormalities in the cholinergic system. However, the relationship between PD and cholinergic dysfunction, particularly in exosomes, is not fully understood.
Methods: We enrolled 37 patients with PD and 44 healthy controls (HC) to investigate acetylcholinesterase (AChE) activity in CD9-positive and L1CAM-positive exosomes.
J Microbiol Biotechnol
April 2024
Microorganisms usually coexist as a multifaceted polymicrobial community in the natural habitats and at mucosal sites of the human body. Two opportunistic human pathogens, and commonly coexist in the bacterial infections for hospitalized and/or immunocompromised patients. Here, we observed that autolysis of the quorum-sensing (QS) mutant () was suppressed by the presence of the cells in vitro.
View Article and Find Full Text PDFBacteriophages (phages) are natural antibiotics and biological nanoparticles, whose application is significantly boosted by recent advances of synthetic biology tools. Designer phages are synthetic phages created by genome engineering in a way to increase the benefits or decrease the drawbacks of natural phages. Here we report the development of a straightforward genome engineering method to efficiently obtain engineered phages in a model bacterial pathogen, Pseudomonas aeruginosa.
View Article and Find Full Text PDFHost range of a phage is determined at the various life cycle stages during phage infection. We reported the limited phage-receptor interaction between the RNA phage, PP7 and its host strains: PAO1 has susceptible type IV pilus (TFP) pilin, whereas PA14 has resistant pilin. Here, we have created a PA14 derivative (PA14P) with the PAO1 pilin gene and found that other determinants than TFP pilin could limit PP7 infectivity in PA14P.
View Article and Find Full Text PDFArtemisinin (ARS) displayed bactericidal activity against . To assess the mechanistic details of its antibacterial action, we have isolated mutants with enhanced ARS resistance and identified a gene (VCA0767) whose loss-of-function resulted in the ARS resistance phenotypes. This gene () encodes a TetR family transcriptional regulator, and its deletion mutant displayed the reduction in ARS-induced ROS formation and DNA damage.
View Article and Find Full Text PDFFront Aging Neurosci
December 2023
Background: Oligomeric Aβ (OAβ) is a promising candidate marker for Alzheimer's disease (AD) diagnosis. Electroencephalography (EEG) is a potential tool for early detection of AD. Still, whether EEG power ratios, particularly the theta/alpha ratio (TAR) and theta/beta ratio (TBR), reflect Aβ burden-a primary mechanism underlying cognitive impairment and AD.
View Article and Find Full Text PDFBackground: Pectobacterium species are necrotrophic phytopathogenic bacteria that cause soft rot disease in economically important crops. The successful infection of host plants relies on interactions among virulence factors, competition, and transmission within hosts. Pectobacteria primarily produce and secrete plant cell-wall degrading enzymes (PCWDEs) for virulence.
View Article and Find Full Text PDFBackground/aims: Pseudoexfoliation (PEX) syndrome is an age-related disorder characterized by the accumulation of extracellular material in the anterior eye segment. PEX pathogenesis is not fully understood, but amyloid which accumulates in the brain of patients with Alzheimer's disease (AD) is a PEX component. PEX deposition shares features with amyloid aggregation in AD, and brain atrophy is a common AD feature, with β-amyloid accumulation among contributing factors.
View Article and Find Full Text PDFThe etiology of early-onset Alzheimer's disease (EOAD) is associated with alterations in the production of amyloid beta (Aβ) species caused by mutations in the , , and genes. Mutations affect intra- or inter-molecular interactions and processes between the γ-secretase complex and amyloid precursor protein (APP), leading to the aberrant sequential cleavage of Aβ species. A 64-year-old woman presented with progressive memory decline, mild right hippocampal atrophy, and a family history of Alzheimer's dementia (AD).
View Article and Find Full Text PDFEarly-onset Alzheimer’s disease (EOAD) is characterized by the presence of neurological symptoms in patients with Alzheimer’s disease (AD) before 65 years of age. Mutations in pathological genes, including amyloid protein precursor (APP), presenilin-1 (PSEN1), and presenilin-2 (PSEN2), were associated with EOAD. Seventy-six mutations in PSEN2 have been found around the world, which could affect the activity of γ-secretase in amyloid beta processing.
View Article and Find Full Text PDFExosomes, which are small extracellular vesicles produced from various cell types, contain a variety of molecular constituents, such as proteins, lipids, and RNA. Recently, exosomal biomarkers have been investigated to probe the understanding and diagnosis of neurodegenerative disorders. Previous reports have demonstrated increased exosomal α-synuclein (α-syn) in patients with Parkinson's disease (PD) in comparison to healthy controls (HC).
View Article and Find Full Text PDFUnruptured intracranial aneurysms have a risk of rupture, so coil embolization is widely practiced as it preserves a patent artery. There are complications of coil procedures, such as patent artery occlusion and thromboembolism, which can result in retinal artery occlusion. We report onretinal artery occlusion following coil embolization of anterior communicating artery aneurysm.
View Article and Find Full Text PDFPP7 is a leviphage, with a single-stranded RNA genome, that infects PAO1. A reverse genetic system for PP7 was previously created by using reverse-transcribed cDNA (PP7) from a virion-derived RNA genome. Here, we have found that the PP7 cDNA contained 20 nucleotide differences from the PP7 genome sequence deposited in the database.
View Article and Find Full Text PDFPolymyxin B (PMB) is known to require reactive oxygen species (ROS) for its bactericidal activity, but the mechanism of PMB resistance in various strains has been poorly understood. This study examined the role of nitrate respiration (NR) of some strains in the PMB resistance. We observed that the minimum inhibitory concentration (MIC) value of PMB against PA14 was eightfold reduced (from 2.
View Article and Find Full Text PDFDespite the successful use of antibacterials, the emergence of multidrug-resistant bacteria has become a serious threat to global healthcare. In this era of antibacterial crisis, bacteriophages (phages) are being explored as an antibacterial treatment option since they possess a number of advantages over conventional antibacterials, especially in terms of specificity and biosafety; phages specifically lyse target bacteria while not affecting normal and/or beneficial bacteria and display little or no toxicity in that they are mainly composed of proteins and nucleic acids, which consequently significantly reduces the time and cost involved in antibacterial development. However, these benefits also create potential issues regarding antibacterial spectra and host immunity; the antibacterial spectra being very narrow when compared to those of chemicals, with the phage materials making it possible to trigger host immune responses, which ultimately disarm antibacterial efficacy upon successive treatments.
View Article and Find Full Text PDFOxidative stress arises from an imbalance between the excessive accumulation of reactive oxygen species (ROS) and a cell's capability to readily detoxify them. Although ROS are spontaneously generated during the normal oxygen respiration and metabolism, the ROS generation is usually augmented by redox-cycling agents, membrane disrupters, and bactericidal antibiotics, which contributes their antimicrobial bioactivity. It is noted that all the bacteria deploy an arsenal of inducible antioxidant defense systems to cope with the devastating effect exerted by the oxidative stress: these systems include the antioxidant effectors such as catalases and the master regulators such as OxyR.
View Article and Find Full Text PDFSince Bacillus anthracis is a high-risk pathogen and a potential tool for bioterrorism, numerous therapeutic methods including passive immunization have been actively developed. Using a human monoclonal antibody phage display library, we screened new therapeutic antibodies for anthrax infection against protective antigen (PA) of B. anthracis.
View Article and Find Full Text PDF