A5032294184- Bacterial biofilms and quorum sensing
- Spectroscopy Techniques in Biomedical and Chemical Research
- 3D Printing in Biomedical Research
- Pickering emulsions and particle stabilization
- Wnt/β-catenin signaling in development and cancer
- Antimicrobial agents and applications
- Photonic Crystals and Applications
- Innovative Microfluidic and Catalytic Techniques Innovation
- Microfluidic and Bio-sensing Technologies
- Marine Biology and Environmental Chemistry
- Antimicrobial Peptides and Activities
- Wound Healing and Treatments
- Orbital Angular Momentum in Optics
- Viral Infectious Diseases and Gene Expression in Insects
- Corneal surgery and disorders
- Connective tissue disorders research
- Spectroscopy and Quantum Chemical Studies
- Bacterial Genetics and Biotechnology
- RNA Research and Splicing
- Fibroblast Growth Factor Research
- Mass Spectrometry Techniques and Applications
- Advanced Fluorescence Microscopy Techniques
- Tissue Engineering and Regenerative Medicine
- Advanced Biosensing Techniques and Applications
- Polymer Surface Interaction Studies
National Institute of Standards and Technology
2023-2024
Virginia Tech
2015-2022
University of California, Davis
2014-2021
We demonstrate that the surface motility of bacterium, Pseudomonas aeruginosa, is hindered by a crystalline hemispherical topography with wavelength in range 2–8 μm. The was determined analysis time-lapse microscopy images cells flowing growth medium maintained at 37 °C. net displacement bacteria over 5 min much lower on surfaces containing μm hemispheres than flat topography, but 1 not lower. That is, there threshold between and 2 for response to topography. Cells 4 were more likely travel...
// Joshua T. Morgan 1,* , Vijay Krishna Raghunathan Yow-Ren Chang 1 Christopher J. Murphy 1,2 and Paul Russell Department of Surgical Radiological Sciences, School Veterinary Medicine, University California, Davis, CA, USA 2 Ophthalmology & Vision Science, * These authors have contributed equally to this work Correspondence to: Russell, email: Keywords : trabecular meshwork, senescence, mechanobiology, cytoskeleton Received February 28, 2015 Accepted March 20, Published April 12, Abstract...
Pseudoexfoliation syndrome is a systemic disorder of the extracellular matrix (ECM) with ocular manifestations in form chronic open angle glaucoma. Elevated levels TGFβ3 aqueous humor individuals pseudoexfoliation glaucoma (PEX) have been reported. The influence on biochemical composition and biomechanics ECM human trabecular meshwork (HTM) cells was investigated. HTM from eye bank donor eyes were isolated, plated aminosilane functionalized glass substrates cultured presence or absence 1...
The objective of this work was to examine whether close-packed spheres polystyrene (colloidal crystals) could be used delay the development biofilms. We examined early stage biofilm formation Pseudomonas aeruginosa after 2 days on a flat sheet and same solid coated in 450 or 1500 nm diameter. All materials were fetal bovine serum enable comparison effects different surface curvature while maintaining constant chemistry. After days, fluorescence imaging showed that volume bacterial colonies...
A growing body of literature broadly documents that a wide array fundamental cell behaviors are modulated by the physical attributes cellular microenvironment, yet in vitro assays typically carried out using tissue culture plastic or glass substrates lack 3-dimensional topography present vivo and have stiffness values far exceed stromal microenvironments. This work presents method for fabrication thin hydrogel films can replicate arbitrary topographies with resolution 400 nm possess an...
Glycans are oligosaccharides attached to proteins or lipids and affect their functions, such as drug efficacy, structural contribution, metabolism, immunogenicity, molecular recognition. Conventional glycosylation analysis has relied on destructive, slow, system-sensitive methods, including enzymatic reactions, chromatography, fluorescence labeling, mass spectrometry. Herein, we propose quantum cascade laser (QCL) infrared (IR) spectroscopy a rapid, nondestructive method quantify glycans...
We examined the effect of a crystalline layer silica particles in size range 0.5–4 μm on adsorption and surface growth Pseudomonas aeruginosa. Growth these colloidal crystal monolayers (CCMs) was compared to flat plate silica. All surfaces were coated with thin film provide chemical uniformity different topographies. The results showed that CCM reduces density colony forming units (CFU) solid by 99–99.9% when suspension load 103 CFU. also interaction between either antibiotics or chemically...
Bacteria traverse surfaces as part of colonizing solids, and it is interest to hinder this motion potentially thwart infections in humans. Here, we demonstrate that topographical steps the ability Pseudomonas aeruginosa PAO1 (P. aeruginosa) a solid–liquid interface. Using time-lapse fluorescence microscopy image analysis, analyzed P. were challenged with ranging height from 0.4 9.0 μm. Bacterial trajectories are sensitive step, curvature step face, direction their relative gravity. When ≥0.9...
Balanced detection based on double beams is widely used to reduce common-mode noises, such as laser intensity fluctuation and irregular wavelength scanning, in absorption spectroscopy. However, employing an additional detector can increase the total system noise due added non-negligible thermal of detector, particularly with mid-infrared (IR) detectors. Herein, we demonstrate a new optical method double-beam modulation (DBM) that uses single-element but keeps advantage balanced detection....
Re-epithelialization of wounds is a critical element wound closure. Growth factors have been used in combination with conventional management to promote closure, but the method delivery has limited topical application ointment formulations. Cytoactive delivered this way short resident times and met success. Here, we demonstrate that methods covalently immobilize proteins on synthetic materials can be extended cytoactive such as epidermal growth factor (EGF) onto beds genetically diabetic...
Absolute quantity imaging of biomolecules on a single cell level is critical for measurement assurance in biosciences and bioindustries. While infrared (IR) transmission microscopy powerful label-free modality capable chemical quantification, its applicability to hydrated biological samples remains challenging due the strong water absorption. We overcome this challenge by applying solvent absorption compensation (SAC) technique home-built quantum cascade laser IR microscope. SAC-IR improves...
In this work, we quantitatively compare computer simulations and existing cell tracking data of P. aeruginosa surface motility in order to analyse the underlying mechanism. We present a three dimensional twitching model, that simulates extension, retraction association individual Type IV Pili (TFP), is informed by recent experimental observations TFP. Sensitivity analysis implemented minimise number model parameters, quantitative estimates for remaining parameters are inferred from...
Absolute quantity imaging of biomolecules on a single cell level is critical for measurement assurance in biosciences and bioindustries. While infrared (IR) transmission microscopy powerful label-free modality capable chemical quantification, its applicability to hydrated biological samples remains challenging due the strong IR absorption by water. Traditional cells relies light sources, such as synchrotrons, mitigate However, we overcome this challenge applying solvent compensation (SAC)...
Infrared (IR) absorption microscopy is a sensitive label-free chemical imaging tool for biomolecules in cells and tissues. However, quantitative measurements hydrated biological samples remain challenge due to the strong water fingerprint region, particular near 1650 cm-1, which critically overlaps with protein amide I peak. Here, we present new approach overcome by using Solvent Absorption Compensation (SAC) unit, dynamically adjusts intensity of incident light compensate absorption. We...
This study investigates how the recent history of bacteria affects their attachment to a solid-liquid interface. We compare from flowing suspension bacterium,Pseudomonas aeruginosaPAO1, after one two histories: (a) passage through tube packed with glass beads or (b) an empty tube. The were designed increase rate bacterial interactions surfaces prior observation in flow cell. Analysis time-lapse microscopy cells shows that residence time distribution and surface density differ for these...