The purpose of this investigation was to evaluate the effects of bacterial products derived from Pseudomonas aeruginosa on the function of airway cilia and to assess the role of phagocytes and oxygen radicals in the observed responses. Ciliary beat frequency (CBF) was measured in a perfusion chamber with a microscopic technique using tracheal epithelial cells obtained from normal sheep by brush biopsy (70% epithelial cells, 18% macrophages, 11% neutrophils). Baseline CBF ranged between 678 and 1,126 min-1. After 20 min of perfusion with the cell free supernatant of P. aeruginosa culture (mucoid strain), a concentration-dependent depression of CBF was observed with a 58% inhibition at a 1:1 dilution (P less than 0.05). The P. aeruginosa-derived products pyocyanin and 1-hydroxyphenazine also decreased CBF in a dose-related fashion. The cilion-inhibitory effects of the supernatant and bacterial products were markedly attenuated after centrifugation of the brush preparation (80% epithelial cells, 16.5% macrophages, 3.5% neutrophils). Glucose/glucose oxidase also caused a rapid, concentration-dependent cilioinhibition or ciliostasis. Catalase blocked or attenuated the ciliary effects of the supernatant, bacterial products and glucose/glucose oxidase. Thus bacterial products released from P. aeruginosa impaired ciliary activity by a pathway which involved neutrophils and was mediated by toxic oxygen radicals.
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http://dx.doi.org/10.1152/ajplung.1991.260.2.L61 | DOI Listing |
World J Microbiol Biotechnol
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College of Chemistry and Chemical Engineering, Xi'an Shiyou University, Xi'an, 710065, China.
This paper developed an efficient microbial activator formula and conducted an in-depth study on its efficacy and mechanism in promoting the degradation of petroleum hydrocarbons in oil-contaminated soil. A 60-day microbial remediation experiment conducted on oily soil revealed that the microbial activators significantly boosted the activities of dehydrogenase and catalase, subsequently speeding up the degradation of petroleum hydrocarbons in the soil. The overall degradation rate reached as high as 71.
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School of Microbiology, University College Cork, Cork, T12 YT20, Ireland.
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January 2025
College of Chemistry, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China. Electronic address:
The advancement of active packaging for food conservation has attracted considerable interest over time. In the present study, we aims to create and examine active films composed of chitosan (CS), poly(vinyl alcohol) (PVA), and syzygium guineense plant extract (SYZ) for potential use in food preservation. We examined the impact of ethanol extracts from the SYZ plant on the films' tensile strength, physical, antibacterial, and anti-oxidant properties.
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January 2025
Laboratory of Vascular Physiology, Department of Physiology and Biophysics, Institute of Biomedical Science, University of Sao Paulo, Sao Paulo, Brazil. Electronic address:
It has been established that cross-fostering impacts the development of hypertension in spontaneously hypertensive rats (SHR). However, the ability of the cross-fostering protocol to shape gut microbiota profile in SHR and impact hypertension is not known. In this sense, the current study explored the influence of normotensive and hypertensive postnatal environments on the intestinal microbiota structure, composition, and functional capacity of SHR and Wistar rats.
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Department of radiology, Affiliated Hospital of Jiangnan University, Wuxi, Jiangsu, 214122, China. Electronic address:
Nanohybrids combining phenylboronic acid-modified carbon dots (PCDs) and proteinase K have been engineered for addressing the formidable challenges of antimicrobial photodynamic therapy (aPDT) against bacterial biofilm infections, overcoming biofilm barrier obstruction, the limited diffusion of reactive oxygen species (ROS), and the inadequate ROS generation of traditional photosensitizers. PCDs are formulated for superior water solubility and robust singlet oxygen (O) production, mitigating issues related to dispersion and aggregation-induced quenching typical of conventional photosensitizers. The conjugation of phenylboronic acid to CDs not only enhanced O generation through increased electron-hole separation but also imparted strong bacterial binding capabilities to the PCDs, enabling broad-spectrum sterilization by maximizing the ROS-mediated bacterial destruction.
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