Article
Biology
Jingru Shi, Chen Chen, Dejuan Wang, Zhiqiang Wang, Yuan Liu
Summary: The prevalence of multidrug-resistant pathogens poses a significant health risk, and there is an urgent need for new antimicrobial agents. This study introduces a synthetic peptide compound, LI14, with potent antibacterial activity against drug-resistant bacteria and a low propensity to induce resistance.
COMMUNICATIONS BIOLOGY
(2022)
Article
Chemistry, Medicinal
George A. Naclerio, Herman O. Sintim
Summary: HP-29, a newly developed halogenated phenazine, exhibits potent antimicrobial activity with a remarkable minimum inhibitory concentration of 0.08 mu M against methicillin-resistant Staphylococcus aureus (MRSA). In addition to eradicating preformed biofilm through iron starvation, HP-29 is also non-toxic to mammalian cell lines and efficacious in wound infection models.
JOURNAL OF MEDICINAL CHEMISTRY
(2021)
Review
Engineering, Environmental
Ana C. Afonso, Ines B. Gomes, Maria Jose Saavedra, Efstathios Giaouris, Lucia C. Simoes, Manuel Simoes
Summary: Bacterial coaggregation is believed to be a key step in the formation of sessile communities in aquatic systems, with bacteria capable of autoaggregation and coaggregation being found in various aquatic systems. The coaggregation mechanism plays an important role in the development and stability of multispecies biofilms, particularly with potential implications for controlling undesirable biofilms in wastewater treatment plants.
Review
Biotechnology & Applied Microbiology
Zhong Li, Xinyu Wang, Jie Wang, Xinyi Yuan, Xiaoyu Jiang, Yanyi Wang, Chao Zhong, Dake Xu, Tingyue Gu, Fuhui Wang
Summary: Biofilms, traditionally seen as problematic, possess favorable traits and have potential applications in various fields. Researchers have designed strategies to create functional biofilms through integration of signaling pathways, engineering of metabolic pathways, and modification of extracellular polymeric substances. Future advancements in synthetic biology and other disciplines will lead to practical large-scale applications of biofilms.
BIOTECHNOLOGY ADVANCES
(2022)
Article
Multidisciplinary Sciences
Mohit P. Dalwadi, Philip Pearce
Summary: Bacteria use quorum sensing to collectively respond to their environment, with their autoinducers affected by factors such as fluid flow. Understanding how genetic architectures in cells promote population-level phenotypes in varying flow conditions reveals that positive feedback in cells can lead to a robust collective response. By accounting for dynamic flow, positive feedback acts as a low-pass filter in oscillatory flow, allowing populations to respond to changes over slow timescales.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Chemistry, Multidisciplinary
Elif N. Hayta, Marvin J. Ertelt, Martin Kretschmer, Oliver Lieleg
Summary: Bacteria have developed clever strategies over millennia to build biopolymer-based communities with fascinating material properties such as sticking to surfaces, repelling water and oils, and even transporting electrons. Material scientists have been inspired by the versatility of bacterial biofilms to create materials for various applications, seeking to improve properties and expand functionalities. By utilizing natural or modified bacterial biofilms, materials with improved properties have been created for diverse fields ranging from agriculture to construction engineering.
ADVANCED MATERIALS INTERFACES
(2021)
Article
Chemistry, Multidisciplinary
Lei Li, Guoqing Zhu, Wencheng Xu, Man Wang, Yulin Xie, Zixian Bao, Manlin Qi, Minghong Gao, Chunxia Li
Summary: This study reports novel composite nanoparticles (mPt/ICG-αA NPs) that combine photodynamic therapy (PDT), photothermal therapy (PTT), and α-amylase enzymatic activities for treating multidrug-resistant bacterial infections and wound healing. The combination of mPt and ICG enhances the effect of PTT, leading to efficient bacterial degeneration. The mPt/ICG-αA NPs also exhibit catalase activity and can continuously decompose endogenous H2O2 to enhance the PDT effect and achieve broad-spectrum bactericidal activity.
Article
Nanoscience & Nanotechnology
Ambika Somasundar, Boyang Qin, Suin Shim, Bonnie L. Bassler, Howard A. Stone
Summary: Bacterial biofilms are communities of cells adhered to surfaces and represent a predominant form of bacterial life on Earth. A key feature of biofilms is the extracellular polymer matrix that acts as a barrier to chemicals, including antimicrobials. This study explores the use of externally imposed chemical gradients to transport particles into bacterial biofilms, demonstrating the importance of chemical gradients in disrupting biofilm matrix and regulating particle transport. The findings suggest potential applications in other physiological systems.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Surgery
Thomas S. Decates, Andries E. Budding, Peter J. Velthuis, Yara Bachour, Lisanne W. Wolters, Leonie W. Schelke, Tamar E. C. Nijsten, Frank B. Niessen
Summary: This study found that the treatment algorithm for late-onset inflammatory adverse events with soft-tissue fillers depends on the causative factor: immunologic or bacterial. The results showed a high level of Gram-positive bacteria in fillers, suggesting that they were introduced during injection. Contamination from skin microbiota during sampling was excluded.
PLASTIC AND RECONSTRUCTIVE SURGERY
(2023)
Article
Multidisciplinary Sciences
Joel A. Finbloom, Preethi Raghavan, Michael Kwon, Bhushan N. Kharbikar, Michelle A. Yu, Tejal A. Desai
Summary: Researchers have developed a nanoscale drug carrier that can deliver both antibiotics and antimicrobial silver nanoparticles to bacterial infections, showing synergistic antimicrobial effects against Pseudomonas aeruginosa. The carrier has also demonstrated positive outcomes in reducing bacterial burden and improving survival outcomes in a mouse model of lung infection.
Article
Biochemistry & Molecular Biology
Marc Hennes, Niklas Bender, Tom Cronenberg, Anton Welker, Berenike Maier
Summary: Membrane potential in bacterial colonies of Neisseria gonorrhoeae transitions from uncorrelated to collective dynamics as the colonies reach a critical size. A hyperpolarized shell forms at the center and travels outward, followed by an influx of potassium correlated with depolarization. Oxygen gradients play a significant role in shaping the collective polarization dynamics and the hyperpolarized shell increases tolerance against aminoglycoside antibiotics, indicating distinct subpopulations within the colonies.
Review
Microbiology
Faizan Ahmed Sadiq, Mette Burmolle, Marc Heyndrickx, Steve Flint, Wenwei Lu, Wei Chen, Jianxin Zhao, Hao Zhang
Summary: Most bacterial species exist in the form of surface-adhered communities or biofilms in various environments. Researchers are now focusing on studying multispecies biofilms and revealing interspecific interactions due to the coexistence of numerous bacterial species. Emergent properties in multispecies biofilms are triggered by bacterial social interactions, which are important for controlling and manipulating microbial communities.
CRITICAL REVIEWS IN MICROBIOLOGY
(2021)
Article
Engineering, Environmental
David R. Espeso, Esteban Martinez-Garcia, Victor de Lorenzo
Summary: The efficiency of multi-strain planktonic flocs of bacteria depends on their three-dimensional aggregation patterns. A methodology for quantitatively portraying and identifying suspended cell clumps was presented in this work, with a focus on Pseudomonas putida species. Microscopy and flow cytometry data were used to create comparable clumping footprints for every sample at both single-cell and population level.
Article
Chemistry, Multidisciplinary
Samuel G. V. Charlton, Amber N. Bible, Eleonora Secchi, Jennifer L. Morrell-Falvey, Scott T. Retterer, Thomas P. Curtis, Jinju Chen, Saikat Jana
Summary: Biofilms are bacterial communities structured within an extracellular matrix, which plays a role in controlling their architecture and mechanical resistance. The research investigates the correlation between biofilm structure and viscoelastic response by comparing biofilms of Pantoea sp. (WT) and a mutant (& UDelta;UDP) with reduced exopolysaccharide production.
Article
Microbiology
Chang Liu, Hua Zhang, Xian Peng, Meghan S. Blackledge, Robert E. Furlani, Haoting Li, Zhaoming Su, Roberta J. Melander, Christian Melander, Suzanne Michalek, Hui Wu
Summary: Antibiotic resistance is a major concern in public health, and new alternatives to combat biofilm-driven infections are needed. A 2-aminoimidazole derivative has been identified to inhibit biofilm formation in Streptococcus mutans and Staphylococcus aureus by targeting a key transcriptional regulator. This compound shows promise as a new anti-infective agent that can attenuate virulence in bacterial infections.
Article
Physics, Multidisciplinary
Parisa Bazazi, Howard A. Stone, S. Hossein Hejazi
Summary: This study experimentally investigates the break-up of a liquid filament with silica nanoparticles in a surfactant-containing oil phase. It is found that when a viscoelastic layer forms at the interface, the pinch-off dynamics follows exponential decay. A simple approach is introduced to estimate the viscoelastic properties of liquid-fluid interfaces and the thickness of the interfacial layer, where direct measurement of interfacial rheology is not possible.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Fluids & Plasmas
Christina Kurzthaler, Rodolfo Brandao, Ory Schnitzer, Howard A. Stone
Summary: In this study, we investigate the steady-state deformation of an elastic filament in various unidirectional, low-Reynolds-number flows. We consider two cases: the filament is either clamped at one end or tethered at its center and deforming symmetrically. We use a slender-body model to describe the filament shape as a function of the flow and a nondimensional compliance ratio. We analyze the small deformation and singular limit of the filament under different flow profiles, comparing numerical solutions with closed-form predictions obtained in both asymptotic limits.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Physics, Fluids & Plasmas
Azmaine Iqtidar, Joseph J. Kilbride, Fouzia F. Ouali, David J. Fairhurst, Howard A. Stone, Hassan Masoud
Summary: In this study, we analyze the diffusion-controlled evaporation of multiple droplets placed near each other on a planar substrate. We calculate the change in volume of sessile droplets with different initial contact angles and arrangements. Experimental measurements using a pattern placed beneath the droplet array validate the theoretical predictions and offer additional insights into the droplet volume evolution.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Mechanics
Ivan C. Christov, Howard A. Stone
Summary: This study provides new concepts for understanding the transport phenomena in granular material flows by introducing a non-Fickian macroscopic model of axial diffusion in a cylindrical tumbler. The model considers diffusion induced by particle collisions only in a thin surface flowing layer due to shear localization. All model parameters are linked to measurable quantities in the granular flow. The proposed model is shown to be a specific case of linear constitutive relations with memory. An exact solution for the spreading of a finite-width pulse initial condition under the non-Fickian model is derived and compared to the solution of the Fickian model.
MECHANICS RESEARCH COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Steven G. Harrellson, Michael S. DeLay, Xi Chen, Ahmet-Hamdi Cavusoglu, Jonathan Dworkin, Howard A. Stone, Ozgur Sahin
Summary: Hygroscopic biological matter in plants, fungi and bacteria plays a significant role in Earth's biomass. These materials exchange water with the environment, exhibit similar mechanical behaviors controlled by the hydration force, and can give rise to a distinct class of solid matter called "hydration solid".
Article
Multidisciplinary Sciences
Zehao Pan, Janine K. Nunes, Camille Duprat, Ho Cheung Shum, Howard A. Stone
Summary: When a suspension of particles passes through a constriction, the particle volume fraction either decreases or remains unchanged. However, an entangled fiber suspension can increase its volume fraction by over 10 times after passing through a constriction. This increase is attributed to the entanglements among the fibers, which allow the network to move faster than the liquid. This finding provides a new strategy to control soft material properties during delivery processes in healthcare, 3D printing, and material repair.
NATURE COMMUNICATIONS
(2023)
Article
Multidisciplinary Sciences
Bernardo Gouveia, Sagar U. Setru, Matthew R. King, Aaron Hamlin, Howard A. Stone, Joshua W. Shaevitz, Sabine Petry
Summary: Microtubules are generated at various sites during cell division, including centrosomes, chromosomes, and within spindles. This study focuses on the nucleation of microtubules at chromosomes, revealing that chromosomes alone can trigger branching microtubule nucleation. The researchers observe this process using fluorescence microscopy and propose a theoretical model involving the release of effectors by chromosomes to spatially bias branching nucleation. These branched networks ultimately organize into functional spindles, with their number scaling with the number of chromosomes and chromatin area.
NATURE COMMUNICATIONS
(2023)
Editorial Material
Biology
Thomas S. Shimizu, E. Toby Kiers, Howard A. Stone
Summary: A new mechanism for vein remodeling in vascular networks is proposed based on a combination of in toto imaging and theory.
Article
Nanoscience & Nanotechnology
Ambika Somasundar, Boyang Qin, Suin Shim, Bonnie L. Bassler, Howard A. Stone
Summary: Bacterial biofilms are communities of cells adhered to surfaces and represent a predominant form of bacterial life on Earth. A key feature of biofilms is the extracellular polymer matrix that acts as a barrier to chemicals, including antimicrobials. This study explores the use of externally imposed chemical gradients to transport particles into bacterial biofilms, demonstrating the importance of chemical gradients in disrupting biofilm matrix and regulating particle transport. The findings suggest potential applications in other physiological systems.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Physics, Multidisciplinary
Jessica L. Wilson, Amir A. Pahlavan, Martin A. Erinin, Camille Duprat, Luc Deike, Howard A. Stone
Summary: The wetting behavior of drops attached to fibers can be influenced by a background airflow, resulting in alignment, repulsion, and coalescence processes. Understanding the behavior of fiber-attached drops in the presence of airflow and controlling drop motion and coalescence are challenging but significant for various applications. Through experiments, it is shown that wetting drops on parallel fibers can aerodynamically interact both with their downstream and upstream neighbors in a uniform air flow, leading to different behaviors such as alignment and coalescence. Particle-image velocimetry is used to visualize wake patterns and explain these behaviors.
Article
Multidisciplinary Sciences
Lisong Yang, Amir A. Pahlavan, Howard A. Stone, Colin D. Bain
Summary: This study investigates the drying dynamics of alcohol droplets on surfaces and the influence of ambient humidity. The researchers observe complex drying behavior due to water condensation on the alcohol droplets, and propose a lubrication model to explain the phenomena.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Physical
Howard A. Stone, Michael J. Shelley, Evgeniy Boyko
Summary: This article presents a derivation of time derivatives commonly used in continuum descriptions of complex fluid flows, using the principles of line element kinematics. The evolution of microstructural conformation tensor in a flow and the physical interpretation of different derivatives are then naturally obtained.
Article
Chemistry, Physical
Niki Abbasi, Janine K. Nunes, Zehao Pan, Tejas Dethe, Ho Cheung Shum, Andrej Kosmrlj, Howard A. Stone
Summary: Liquid-liquid phase separation induced by co-flow of a nonequilibrated aqueous two-phase system within a planar flow-focusing microfluidic device is experimentally demonstrated. Invasion fronts from the outer stream are formed along the top and bottom walls of the microfluidic device, which merge as the system reaches steady-state. The formation and growth of the invasion fronts are driven by Marangoni flow induced by the polymer concentration gradient along the width of the channel during phase separation.
Article
Physics, Fluids & Plasmas
Marcel M. Louis, Evgeniy Boyko, Howard A. Stone
Summary: This study investigates the influence of temperature-dependent viscosity on the relationship between pressure drop and flow rate in pipe flows. Different temperature boundary conditions are applied to change the viscosity field under the same flow conditions and compare how external heating affects the pressure drop. Analytical and similarity-solution methods are used to solve for the temperature distribution under constant temperature and constant heat flux boundary conditions, as well as assumed linear and polynomial temperature versus distance boundary conditions at the wall. The lubrication and boundary-layer approximations are used for the momentum and energy equations, respectively. The reciprocal theorem is used to derive an expression for the pressure drop for a viscosity field that depends on temperature and spatially varies across and along the flow. Assuming a small fractional change in viscosity with temperature, an analytical expression for the pressure drop for a given flow rate is obtained. The numerical results are compared with analytical predictions in the low and high Peclet number limits.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Physics, Fluids & Plasmas
Anneline H. Christensen, Ankur Gupta, Guang Chen, Winfried S. Peters, Michael Knoblauch, Howard A. Stone, Kaare H. Jensen
Summary: By studying the interaction between charged particles and electrical double layers, we have discovered a system in which the diffusive current increases when the conductive area diminishes. This finding is of great significance for improving filtration efficiency and advancing our understanding of biological pore structures.