Aims: To determine whether intercellular signalling can occur between physically separated populations of Escherichia coli.
Methods And Results: Intercellular signalling between physically discrete populations of E. coli BL21 was analysed in bi-partite Petri dishes. Transfer of a growth-promoting signal resulted in induction of resistance to the antibiotic ampicillin. Optimal expression of the signal occurred when the signalling population was established as a bacterial lawn for 24 h. This represented an entry into the stationary phase of growth, as indicated by the expression profile of the RNA polymerase subunit sigma38 (sigmaS; sigma S). The growth-promoting effect was also observed when E. coli DH5alpha (luxS-) was used as the signalling population. Preventing passage of air between the two populations resulted in a complete cessation of the growth-promoting effect.
Conclusions: A growth-promoting signal occurs between physically separated cultures of E. coli. The exact nature of the signal remains to be determined but does not involve the production of autoinducer-2 from the luxS gene. Signal transmission is likely to involve airborne transfer of a signal species.
Significance And Impact Of The Study: Intercellular signalling systems exist in bacteria that enable antibiotic resistance to be conferred between physically separated populations.
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http://dx.doi.org/10.1046/j.1365-2672.2002.01647.x | DOI Listing |
Sleep Breath
January 2025
Department of Pulmonary and Critical Care Medicine, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, No.1 Da Hua Road, Dong Dan, Dongcheng District, Beijing, 100730, PR China.
Purpose: To investigate the relationship between obstructive sleep apnea hypopnea syndrome (OSAHS) severity and fat, bone, and muscle indices.
Methods: This study included 102 patients with OSAHS and retrospectively reviewed their physical examination data. All patients underwent polysomnography, body composition analysis, dual-energy X-ray absorptiometry, computed tomography (CT) and blood test.
FASEB J
January 2025
National Key Laboratory of Space Medicine, China Astronaut Research and Training Center, Beijing, China.
Microgravity-induced cardiac remodeling and dysfunction present significant challenges to long-term spaceflight, highlighting the urgent need to elucidate the underlying molecular mechanisms and develop precise countermeasures. Previous studies have outlined the important role of miRNAs in cardiovascular disease progression, with miR-199a-3p playing a crucial role in myocardial injury repair and the maintenance of cardiac function. However, the specific role and expression pattern of miR-199a-3p in microgravity-induced cardiac remodeling remain unclear.
View Article and Find Full Text PDFNPJ Precis Oncol
January 2025
Radiation and Environmental Science Centre, Physical to Life Sciences Research Hub, Technological University Dublin, Dublin, Ireland.
Predicting long-term recurrence of disease in breast cancer (BC) patients remains a significant challenge for patients with early stage disease who are at low to intermediate risk of relapse as determined using current clinical tools. Prognostic assays which utilize bulk transcriptomics ignore the spatial context of the cellular material and are, therefore, of limited value in the development of mechanistic models. In this study, Fourier-transform infrared (FTIR) chemical images of BC tissue were used to train deep learning models to predict future disease recurrence.
View Article and Find Full Text PDFNat Commun
January 2025
Institute of Optoelectronic Thin Film Devices and Technology, Key Laboratory of Optoelectronic Thin Film Devices and Technology of Tianjin, College of Electronic Information and Optical Engineering, National Institute for Advanced Materials, Nankai University, Tianjin, China.
Biological neural systems seamlessly integrate perception and action, a feat not efficiently replicated in current physically separated designs of neural-imitating electronics. This segregation hinders coordination and functionality within the neuromorphic system. Here, we present a flexible device tailored for neuromorphic computation and muscle actuation.
View Article and Find Full Text PDFBMJ Mil Health
January 2025
School of Medical, Indigenous and Health Sciences, University of Wollongong, Wollongong, New South Wales, Australia.
Introduction: Infantry is a physically demanding trade that is associated with elevated rates of musculoskeletal injury. A 17-week longitudinal intervention assessed the effect of a progressive increase in load carriage mass and sprint-intensity intervals on physical performance, physical complaints, medical encounters, physical activity and sleep in infantry trainees.
Methods: 91 infantry trainees from 2 separate platoons, randomly assigned as control (CON) or experimental (EXP), provided written voluntary consent.
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