Adaptive locomotion of artificial microswimmers

Science Advances, Год журнала: 2019, Номер 5(1)

Опубликована: Янв. 4, 2019

Bacteria can exploit mechanics to display remarkable plasticity in response locally changing physical and chemical conditions. Compliant structures play a notable role their taxis behavior, specifically for navigation inside complex structured environments. Bioinspired mechanisms with rationally designed architectures capable of large, nonlinear deformation present opportunities introducing autonomy into engineered small-scale devices. This work analyzes the effect hydrodynamic forces rheology local surroundings on swimming at low Reynolds number, identifies challenges benefits using elastohydrodynamic coupling locomotion, further develops suite machinery building untethered microrobots self-regulated mobility. We demonstrate that structural magnetic properties artificial microswimmers dynamic fluid leads adaptive locomotion absence on-board sensors.

Язык: Английский

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Mucus Architecture and Near-Surface Swimming Affect Distinct Salmonella Typhimurium Infection Patterns along the Murine Intestinal Tract

Cell Reports, Год журнала: 2019, Номер 27(9), С. 2665 - 2678.e3

Опубликована: Май 1, 2019

•Live imaging of Salmonella near-surface swimming on mouse colon inner mucus layer•Colon layer traversal requires breaches and flagellar propulsion•The cecum lacks a continuous layer, leaving epithelium tips uncovered•Exposed are hotspot for infection SummaryMucus separates gut-luminal microbes from the tissue. It is unclear how pathogens like Typhimurium (S.Tm) can overcome this obstacle. Using live microscopy, we monitored S.Tm interactions with native murine gut explants studied affects infection. A dense covers distal tissue, limiting direct tissue access. performs which allows probing heterogeneities, but also entrap bacterium in layer. In cecum, fills only bottom intestinal crypts, between crypts unshielded prone to access by motile non-motile bacteria alike. This explains why highly permissive represents primary site enterocolitis streptomycin model. Our findings highlight importance defense homeostasis. Mucus

Язык: Английский

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Wrapped Up: The Motility of Polarly Flagellated Bacteria

Annual Review of Microbiology, Год журнала: 2022, Номер 76(1), С. 349 - 367

Опубликована: Июнь 2, 2022

A huge number of bacterial species are motile by flagella, which allow them to actively move toward favorable environments and away from hazardous areas conquer new habitats. The general perception flagellum-mediated movement chemotaxis is dominated the Escherichia coli paradigm, with its peritrichous flagellation famous run-and-tumble navigation pattern, has shaped view on how bacteria swim navigate in chemical gradients. However, a significant amount-more likely majority-of exhibit (bi)polar flagellar localization pattern instead lateral flagella. Accordingly, these have evolved very different mechanisms for chemotaxis. Here, we review earlier recent findings various modes motility mediated polar

Язык: Английский

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Roadmap for Clinical Translation of Mobile Microrobotics

Advanced Materials, Год журнала: 2024, Номер 36(23)

Опубликована: Фев. 21, 2024

Medical microrobotics is an emerging field to revolutionize clinical applications in diagnostics and therapeutics of various diseases. On the other hand, mobile has important obstacles pass before translation. This article focuses on these challenges provides a roadmap medical microrobots enable their use. From concept "magic bullet" physicochemical interactions complex biological environments applications, there are several translational steps consider. Clinical translation only possible with close collaboration between experts researchers address technical microfabrication, safety, imaging. The application potential can be materialized by designing that solve current main challenges, such as actuation limitations, material stability, imaging constraints. strengths weaknesses progress discussed for near future outlined.

Язык: Английский

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Strategies of Helicobacter pylori in evading host innate and adaptive immunity: insights and prospects for therapeutic targeting

Frontiers in Cellular and Infection Microbiology, Год журнала: 2024, Номер 14

Опубликована: Фев. 26, 2024

Helicobacter pylori ( H. ) is the predominant pathogen causing chronic gastric mucosal infections globally. During period from 2011 to 2022, global prevalence of infection was estimated at 43.1%, while in China, it slightly higher approximately 44.2%. Persistent colonization by can lead gastritis, peptic ulcers, and malignancies such as mucosa-associated lymphoid tissue (MALT) lymphomas adenocarcinomas. Despite eliciting robust immune responses host, thrives mucosa modulating host immunity, particularly altering functions innate adaptive cells, dampening inflammatory adverse its survival, posing challenges clinical management. The interaction between defenses intricate, involving evasion recognition modifying surface molecules, manipulating macrophage functionality, T cell evade surveillance. This review analyzes immunopathogenic mechanisms , underscoring importance identifying new therapeutic targets developing effective treatment strategies, discusses how development vaccines against offers hope for eradicating infections.

Язык: Английский

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Acute Exposure to Commonly Ingested Emulsifiers Alters Intestinal Mucus Structure and Transport Properties

Scientific Reports, Год журнала: 2018, Номер 8(1)

Опубликована: Июнь 27, 2018

The consumption of generally regarded as safe emulsifiers has increased, and been associated with an increased prevalence inflammatory bowel metabolic diseases, well altered microbiome. mucus barrier, which selectively controls the transport particulates microorganisms to underlying epithelial layer, previously shown be by dietary salts lipids. However, potential impact on protective its permeability, structural changes are not clear. In this study, we analyzed in barrier both passively diffusing nanoparticles actively swimming E. coli upon exposure two emulsifiers, carboxymethylcellulose (CMC) polysorbate 80 (Tween). When exposed CMC, pore size decreased, resulted significantly slower speed particle diffusion rates through mucus. Tween minimally impacted microstructure diffusion, but Moreover, appeared alter amount thickness rat intestinal tissue mucus-producing cell cultures. These results indicate that acute impacts properties mucus, modulating interactions between lumen contents, microbes, tissue, may contribute development inflammation.

Язык: Английский

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Swimming with magnets: From biological organisms to synthetic devices

Physics Reports, Год журнала: 2018, Номер 789, С. 1 - 54

Опубликована: Ноя. 19, 2018

Язык: Английский

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Reorientation behavior in the helical motility of light-responsive spiral droplets

Nature Communications, Год журнала: 2019, Номер 10(1)

Опубликована: Ноя. 20, 2019

The physico-chemical processes supporting life's purposeful movement remain essentially unknown. Self-propelling chiral droplets offer a minimalistic model of swimming cells and, in surfactant-rich water, nematic liquid crystals follow the threads screw. We demonstrate that geometry their trajectory is determined by both number turns in, and handedness of, spiral organization. Using molecular motors as photo-invertible dopants allows converting between right-handed left-handed trajectories dynamically, subjected to such an inversion reorient direction also encoded turns. This motile behavior stems from dynamic transmission chirality, artificial crystal confinement eventually helical trajectory, analogy with chirality-operated motion reorientation unicellular organisms.

Язык: Английский

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Campylobacter jejuni motility integrates specialized cell shape, flagellar filament, and motor, to coordinate action of its opposed flagella

PLoS Pathogens, Год журнала: 2020, Номер 16(7), С. e1008620 - e1008620

Опубликована: Июль 2, 2020

Campylobacter jejuni rotates a flagellum at each pole to swim through the viscous mucosa of its hosts' gastrointestinal tracts. Despite their importance for host colonization, however, how C. coordinates rotation these two opposing flagella is unclear. As well as polar placement, jejuni's deviate from norm Enterobacteriaceae in other ways: flagellar motors produce much higher torque and filament made different zones flagellins. To understand opposed coordinate, what contribution factors play motility, we developed strains with that could be fluorescently labeled, observed them by high-speed video microscopy. We found dual wrapping leading around cell body during swimming high-viscosity media differentiated helical have evolved facilitate this wrapped-mode swimming.

Язык: Английский

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Engineering nanoparticles to overcome the mucus barrier for drug delivery: Design, evaluation and state-of-the-art

Medicine in Drug Discovery, Год журнала: 2021, Номер 12, С. 100110 - 100110

Опубликована: Ноя. 10, 2021

Mucus is a viscoelastic hydrogel that lubricates and protects mucosal tissues such as the eyes, lung, gastrointestinal tract, vagina. Nanoparticle-based drug delivery systems (DDSs) can be easily trapped in mucus network by steric obstruction and/or binding interactions then are efficiently cleared away with rapid turnover, thereby limiting efficacy. Modulating physicochemical properties of nanoparticles (NPs), including size, surface hydrophilicity charge, shape, rigidity, an effective method to overcome barrier. This review first describes protective barrier how affects fate NPs. It reviews techniques for evaluating particle movement mucus, macroscopic diffusivity microcosmic diffusion mechanisms. The state-of-the-art strategies exploited researchers using NPs discussed. Finally, dilemma solutions balancing both penetration cellular uptake barriers

Язык: Английский

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