The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
HiLo microscopy is a widefield fluorescence imaging technique that provides depth discrimination by combining two images, one with non-uniform illumination and one with uniform illumination. We discuss the theory of this technique and a variety of practical implementations in brain-tissue imaging and fluorescence endomicroscopy.
The objective of this study was to evaluate the nonlinear optical microscopy techniques of multiphoton autofluorescence microscopy (MPAM) and second harmonic generation microscopy (SHGM) for noninvasive imaging of oral epithelial carcinogenesis. In vivo imaging was performed in a hamster model for oral carcinogenesis to characterize optical and morphometric alterations during neoplastic transformation...
This paper presents new approaches to accelerating x-ray fluorescence tomography (XFCT) that are grounded in both novel image acquisition strategies that improve the quality of the data acquired and in image reconstruction strategies that reduce the amount of data acquired. First, we introduce an alternative imaging scheme that uses an emission tomography (ET) system to collect the fluorescence photons...
We show a platform that merges a microfluidic chip with lensless imaging for CD4+ T-lymphocyte counting at resource-limited settings. To capture CD4+ T lymphocytes, anti-CD4 antibody was immobilized on a microfluidic chip. The captured cells were detected by a charge coupled device (CCD) sensor using lensless shadow imaging techniques. Gray scale shadow images of captured cells on the chip (24 mm...
We have designed, simulated, and fabricated micro-magnetic substrates for the reversible self-assembly of cell-internalized magnetic fluorescent nanoparticles according to lithographically defined patterns within live cells. Magnetic nanoparticles have recently demonstrated potential in activating highly specific activity within single cells. Using microfabrication, we have developed a technique of...
This proceeding studies the optical fluorescence images of a porcine heart filled with microspheres of two colors, carmine and red. A significant difference in the total optical tissue attenuation coefficient was observed between excitation and emission for both carmine (excitation - 13 plusmn 4(1/mm) and emission - 9.4 plusmn 3(1/mm)) and red (excitation -29 plusmn 5(1/mm) and emission - 25 plusmn...
Hydrated nanopores offer a unique environment for studying biological molecules under controlled conditions and fabricating sensors using fluorescence. Silica nanopores for example are non-toxic, biologically and optically compatible with protein, and can be easily synthesized to entrap protein and exclude potentially interfering macromolecules, while transmitting analytes of interest. A well known...
The goal of the present study was to develop a physiologically realistic 3D computational fluid dynamics (CFD) model of the left coronary artery under normal and disease conditions to estimate blood flow induced shear stress, and then use the computed shear stress to stimulate vascular endothelial cells in vitro. A 3D geometry of the left coronary artery was built in ProE and the CFD analysis of the...
The process of developing molecular assays for disease diagnosis and prognosis requires cross-disciplinary research which monitors quality and reproducibility at all levels. This paper discusses challenges in the quality control of highly multiplexed Quantum Dot (QD) staining and provides a method for improving accuracy of QD quantification in two phases. Phase one is the estimation of unintended...
Multimodality molecular imaging is becoming more and more important to understand both the structural and the functional characteristics of tissue, organs and tumors. So far, invasive nuclear methods utilizing ionizing radiation have been the ldquogold standardrdquo of molecular imaging. We investigate non-contact, non-invasive, patient-tolerant and inexpensive near infrared (NIR) frequency domain...
We demonstrate a high sensitivity, high throughput microfabricated cell sorting device with the integrated piezoelectric actuator and optofluidic waveguide on a chip. For automated sorting, field-programmable-gate-array (FPGA) embedded real time control loop system is built. The sorting is performed under high flow rate (~10 cm/sec), and the sorting system can achieve a high throughput (> 1 kHz)...
The excited state of an organic molecule is a crossroads which can lead to many directions, such as non-radiative emission as heat, fluorescence, intersystem crossing and phosphorescence. Due to the unpredictable nature of the excited molecular structure, manipulation of this represents significant challenges for physicists and chemists. However, the successful management of the excited state provides...
The rotational symmetry of point spread function (PSF) is common for many imaging systems such as optical microscopes, cameras, astigmatism corrected electron microscopes, and etc. In 2-D deconvolution problem, we showed that an exact PSF estimation from a single measured image on a flat background is possible by exploiting the circular symmetry. This paper extends the idea to 3-D blind deconvolution...
We demonstrate the utility of the opto-fluidic ring resonator (OFRR) sensor for analyzing methylated oligonucleotides. Cytosine methylation, a regular epigenetic function in cellular growth and metabolism, may have ties to abnormal suppression of key genes involved with cellular proliferation. Such behavior is suspected to be strongly related to the occurrence of several types of cancers. The OFRR...
A new generation of drug carrier that allows efficient delivery and real-time imaging of siRNA in live cells has been developed by combining nanoparticles and amphiphilic polymers. Compared with the classic siRNA carriers such as Lipofectamin and polyetheleneimine, this new class of nanocarrier works in both serum-free and complete cell culture media, which is advantageous over lipofectamine. It also...
The unique photophysical properties of semiconductor quantum dots (QDs) have made them ideal for use as spectral labels and luminescent probes. In this review, applications are presented in which QDs function as active participants in nanoscale biosensor assemblies, where replacing traditional molecular fluorophores results in improved assay performance. Specific focus is on disease detection with...
We present a simple and parameter-free nuclei tracking method for reconstructing cell dynamics in fluorescence 3D+t images of embryogenesis. The strategy is based on the use of the mathematical morphology operators directly in the 4D image. The morphological reconstruction of a marker -manually or automatically selected- in an initial spatio-temporal position generates a connected path over the time...
Precise control of differentiation processes of pluripotent stem cell is key component for realization of regenerative medicine. Electrical stimulation is one of the promising techniques, particularly for regulation of neuronal regeneration. In the present study, we developed substrates with embedded electrodes, which allowed ensemble electrical stimulation of embryoid bodies (EBs) of stem cells....
Multiplexed nanobarcodes have been prepared with quantum dots (QDs) and amphiphilic copolymers consisted of hydrocarbons and maleic anhydride groups. In homogenous solution, the QD-polymer complexes self-assemble into nanobeads with narrow size dispersity, which has been previously achieved only for micrometer-sized beads in the presence of solid supports. More than 250 QDs can be loaded into a nanobead...
Dermally-implanted microparticle sensors are being developed for on-demand monitoring of blood sugar levels. For these to be deployed in vivo, a matched optoelectronic system for delivery of excitation, collection and analysis of escaping fluorescent signal is needed. Previous studies predicted the characteristics of fluorescence from microparticle sensors to facilitate design of hardware system....
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.