Abstract:
:As the most abundant cell type in the central nervous system, astrocyte has been one of main research topics in neuroscience. Although various tools have been developed, at present, there is no tool that allows noninvasive activation of astrocyte in vivo without genetic or pharmacological perturbation. Here we report a noninvasive label-free optical method for physiological astrocyte activation in vivo using a femtosecond pulsed laser. We showed the laser stimulation robustly induced astrocytic calcium activation in vivo and further verified physiological relevance of the calcium increase by demonstrating astrocyte mediated vasodilation in the brain. This novel optical method will facilitate noninvasive physiological study on astrocyte function.
journal_name
J Biomed Optjournal_title
Journal of biomedical opticsauthors
Choi M,Yoon J,Ku T,Choi K,Choi Cdoi
10.1117/1.3600774subject
Has Abstractpub_date
2011-07-01 00:00:00pages
075003issue
7eissn
1083-3668issn
1560-2281journal_volume
16pub_type
杂志文章abstract::We describe the protocol for an inexpensive and nondestructive optical reflectance assay for the measurement of biofilm formation. Reflectance data are obtained using an Ocean Optics (Dunedin, Florida) USB 2000 spectrometer with a polychromatic light source. A fiber optic cable is used both for illumination and collec...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.1953347
更新日期:2005-07-01 00:00:00
abstract::We fabricate scaffolds with a fine linear grating (periodicity of 1 to 8 microm and height of 1 microm) on a glass substrate for controlling cardiomyocyte orientation. The fabrication is done by the solidification of a liquid photopolymerizable material using two laser beam interference. As the photopolymerizable mate...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.2186042
更新日期:2006-03-01 00:00:00
abstract::Biomedical applications of terahertz (THz) radiation are appealing because THz radiation is nonionizing and has the demonstrated ability to detect intrinsic contrasts between cancerous and normal tissue. A linear polarization-sensitive detection technique for tumor margin delineation has already been demonstrated; how...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.21.7.070502
更新日期:2016-07-01 00:00:00
abstract::The effect of silica/gold nanoshells and titanium dioxide nanoparticles on the optical properties of skin is studied. By implementing in vivo measurements and Monte Carlo simulations, we analyze the efficiency of using these nanoparticles as contrasting agents for optical coherence tomography (OCT) imaging of skin. In...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.3122373
更新日期:2009-03-01 00:00:00
abstract::Simplified measurement of macular pigment optical density (MPOD) is important because of the ocular health benefits that are attributed to these retinal carotenoids. Here, we describe a novel instrument designed for this purpose, based on heterochromatic flicker photometry (HFP), which removes a number of difficulties...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.18.10.107003
更新日期:2013-10-01 00:00:00
abstract::We theoretically investigate the effect of noise on frequency-domain heterodyne and/or homodyne measurements of intensity-modulated beams propagating through diffusive media, such as a photon density wave. We assumed that the attenuated amplitude and delayed phase are estimated by taking the Fourier transform of the n...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.17.1.016010
更新日期:2012-01-01 00:00:00
abstract::We demonstrate the in vivo assessment of human scars by parametric imaging of birefringence using polarization-sensitive optical coherence tomography (PS-OCT). Such in vivo assessment is subject to artifacts in the detected birefringence caused by scattering from blood vessels. To reduce these artifacts, we preprocess...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.19.12.126014
更新日期:2014-12-01 00:00:00
abstract::Fluorescence spectroscopy has been widely investigated as a technique for identifying pathological tissue; however, unrelated subject-to-subject variations in spectra complicate data analysis and interpretation. We describe and evaluate a new biosensing technique, differential laser-induced perturbation spectroscopy (...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.17.6.067002
更新日期:2012-06-01 00:00:00
abstract::Toward developing a new method for restoring tissue viscoelasticity in scarred vocal folds, we previously proposed a method to localize biomaterials within subepithelial voids ablated using ultrafast laser pulses. The clinical implementation of this method necessitates the quantification of the laser parameters for ab...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.18.11.118001
更新日期:2013-11-01 00:00:00
abstract::Spasticity is a motor disorder frequently present in individuals with cerebral palsy (CP). This study aimed to evaluate the effect of low-level laser therapy (LLLT) on the spasticity of the masseter and anterior temporal muscle fibers in children with CP over three weeks of intermittent laser exposures. The bite force...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.21.2.028001
更新日期:2016-02-01 00:00:00
abstract::One of the prime limiting factors of optical imaging in biological applications is the diffusion of light by tissue, which prevents focusing at depths greater than the optical diffusion limit (typically ?1??mm). To overcome this challenge, wavefront shaping techniques that use a spatial light modulator (SLM) to correc...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.21.12.121502
更新日期:2016-12-01 00:00:00
abstract::Utilizing a laser scanning confocal microscope system, the refractive indices of articular cartilage (AC) with mechanical or biochemical degenerations were characterized to investigate whether potential correlations exist between refractive index (RI) and cartilage degeneration. The cartilage samples collected from th...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.21.9.095002
更新日期:2016-09-01 00:00:00
abstract::Time-resolved measurement of early arriving photons through diffusive media has been shown to effectively reduce the high degree of light scatter in biological tissue. However, the experimentally achievable reduction in photon scatter and the impact of time-gated detection on instrument noise performance is not well u...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.3523371
更新日期:2010-11-01 00:00:00
abstract::Dynamic analyses of vibrational motion in cell membranes provide a lot of information on the complex dynamic motilities of a red blood cell (RBC). Here, we present the correlation properties of membrane fluctuation in discocyte and spherocyte RBCs by using quantitative phase microscopy (QPM). Since QPM can provide nan...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.3601460
更新日期:2011-07-01 00:00:00
abstract::All aberrations produced inside a biospecimen can degrade the quality of a three-dimensional image in two-photon excitation laser scanning microscopy. Previously, we developed a transmissive liquid-crystal device to correct spherical aberrations that improved the image quality of a fixed-mouse-brain slice treated with...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.21.12.121503
更新日期:2016-12-01 00:00:00
abstract::Optical coherence microscopy (OCM) combines confocal microscopy and optical coherence tomography (OCT) to improve imaging depth and contrast, enabling cellular imaging in human tissues. We aim to investigate OCM for ex vivo imaging of upper and lower gastrointestinal tract tissues, to establish correlations between OC...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.3322704
更新日期:2010-01-01 00:00:00
abstract::The ability to quantitatively determine tissue fluorescence is of interest for the purpose of better understanding the details of photodynamic therapy of skin cancer. In particular, we are interested in quantifying protoporphyrin IX (PpIX) in vivo. We present a method of correcting fluorescence for effects of native t...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.3665440
更新日期:2011-12-01 00:00:00
abstract::A tutorial introduction to diffuse light transport is presented. The basic analytic equations of time-resolved, steady-state and modulated light transport are introduced. The perturbation method for handling slight heterogeneities in optical properties is outlined. The treatment of boundary conditions such as an air/t...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.2967535
更新日期:2008-07-01 00:00:00
abstract::Cell morphology is often used as a valuable indicator of the physical condition and general status of living cells. We demonstrate a noninvasive method for morphological characterization of adherent cells. We measure infrared reflectivity spectrum at oblique angle from living cells cultured on thin Au film, and utiliz...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.17.8.081409
更新日期:2012-08-01 00:00:00
abstract::Muscle blood flow (MBF) and muscle oxygen saturation (SmO(2)) were measured at eight locations (four proximal, four distal) over a 4 x 8 cm(2) area of the vastus lateralis at rest and immediately after isometric, maximal quadriceps contraction using multichannel, frequency-domain, near-infrared spectroscopy. A venous ...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.1646417
更新日期:2004-03-01 00:00:00
abstract::Emission and excitation spectra of collagen were recorded in the ultraviolet and visible regions. The existence of several types of chromophores absorbing and emitting throughout these spectral regions was observed. It was shown that laser irradiation at 355 and 532 nm caused collagen fluorescence photobleaching by 30...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.1331559
更新日期:2001-01-01 00:00:00
abstract::The spatiotemporal characteristics of changes in cerebral blood volume associated with neuronal activity were investigated in the hindlimb somatosensory cortex of alpha-chloralose-urethane anesthetized rats (n=10) with optical imaging at 570 nm through a thinned skull. Activation of the cortex was carried out by elect...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.1609199
更新日期:2003-10-01 00:00:00
abstract::A main field in biomedical optics research is diffuse optical tomography, where intensity variations of the transmitted light traversing through tissue are detected. Mathematical models and reconstruction algorithms based on finite element methods and Monte Carlo simulations describe the light transport inside the tis...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.17.12.126009
更新日期:2012-12-01 00:00:00
abstract::This paper presents a fiber Bragg grating (FBG)-instrumented prosthetic silicone liner that provides cushioning for the residual limb and can successfully measure interface pressures inside prosthetic sockets of lower-limb amputees in a simple and practical means of sensing. The liner is made of two silicone layers be...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.22.8.087001
更新日期:2017-08-01 00:00:00
abstract::As limited data photoacoustic tomographic image reconstruction problem is known to be ill-posed, the iterative reconstruction methods were proven to be effective in terms of providing good quality initial pressure distribution. Often, these iterative methods require a large number of iterations to converge to a soluti...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.23.7.071204
更新日期:2018-02-01 00:00:00
abstract::The conical shape of the tympanic membrane (TM or eardrum) plays an important role in its function, such that variations in shape alter the acoustically induced motions of the TM. We present a method that precisely determines both shape and acoustically induced transient response of the entire TM using the same optics...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.24.3.031008
更新日期:2018-09-01 00:00:00
abstract::Real-time medical imaging systems such as reflectance confocal microscopes and optical coherence microscopes are being tested in multiple-patient and multiple-center clinical trials. The modulation transfer function (MTF) of these systems at any given time influences the image information content and can affect the in...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.2779352
更新日期:2007-09-01 00:00:00
abstract::We investigate the relationship between the laser beam at the retina (spot size) and the extent of retinal injury from single ultrashort laser pulses. From previous studies it is believed that the retinal effect of single 3-ps laser pulses should vary in extent and location, depending on the occurrence of laser-induce...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.1805554
更新日期:2004-11-01 00:00:00
abstract::The earliest steps of breast cancer begin with aberrations in mammary ductal structure. Techniques that enable an investigator to image in situ and then analyze the same tissue using biochemical tools facilitates identification of genetic networks and signaling pathways active in the imaged structure. Cellular confoca...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.2065827
更新日期:2005-09-01 00:00:00
abstract::Laser photocoagulation is an established treatment for a variety of retinal diseases. However, when using the same irradiation parameter, the size and strength of the lesions are unpredictable due to unknown inter- and intraindividual optical properties of the fundus layers. The aim of this work is to investigate a fe...
journal_title:Journal of biomedical optics
pub_type: 杂志文章
doi:10.1117/1.JBO.21.9.098001
更新日期:2016-09-01 00:00:00