CHAMPAIGN, IL, United States
CHAMPAIGN, IL, United States
Time filter
Source Type

Coskun U.C.,ISS, INC. | Lam S.,Washington University in St. Louis | Sun Y.,ISS, INC. | Liao S.-C.J.,ISS, INC. | And 2 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2017

Phosphorescence probes can have significantly long lifetimes, on the order of micro-to milli-seconds or longer. In addition, environmental changes can affect the lifetimes of these phosphorescence probes. Thus, Phosphorescence Lifetime Imaging Microscopy (PLIM) is a very useful tool to localize the phosphorescence probes based on their lifetimes to study the variance in the lifetimes due to the micro environmental changes. Since the probes respond to the biologically relevant parameters like oxygen concentration, they can be used to study various biologically relevant processes like cellular metabolism, protein interaction etc. In this case, we study the effects of oxygen on Oxyphor G4 with PLIM. Since The Oxyphor G4 can be quenched by O2, it is a good example of such a probe and has a lifetime around 250us. Here we present the digital frequency domain PLIM technique and study the lifetime of the Oxyphor G4 as a function of the O2 concentration. The lifetime data are successfully presented in a phasor plot for various O2 concentrations and are consistent with the time domain data. Overall, we can analyze the oxygen consumption of varying cells using this technique. © 2017 SPIE.

Wang D.-S.,National Taiwan University | Wei S.-C.,National Taiwan University | Liao S.-C.,ISS, INC. | Lin C.-W.,National Taiwan University
Microscopy Research and Technique | Year: 2013

Owing to the highly efficient two-photon fluorescence of gold nanorods and very short fluorescence lifetime compared with the rotational correlation time, the rotation and diffusion of a single gold nanorod can be easily observed by two-photon fluorescence correlation spectroscopy (TP-FCS). This property, along with the previous successful use as a contrast agent in two-photon fluorescence imaging, suggests a potential application in TP-FCS as well. Although the FCS measurement becomes highly efficient with gold nanorods as probes, the amplitude and temporal decay of the measured correlation functions depend critically on excitation power. Here, we investigate various photophysical processes of gold nanorods to determine the cause of such a sensitive power dependency. This understanding provides a basis for choosing appropriate FCS models to recover reasonable physical parameters. Although the correlation function amplitude G(0) is 32 times lower when the excitation power increases from 20 μW to 1.12 mW, the application of a saturation-modified FCS model yields very good fit to each data set and the fitted concentration of 0.64 nM is comparable to the 0.7 nM given by the inductively coupled plasma mass spectrometry measurement. The FCS assay appears to be an efficient method for the quantification of gold nanorods when correctly interpreted. However, even with the saturation considered in the fitting model, the fitted rotational and translational diffusion rates are getting faster as the power increases. This indicates that other effects such as photothermal effects may raise the local temperature, and thus increasing the rotational and translational diffusion rate. Microsc. Res. Tech. 76:882-889, 2013. © 2013 Wiley Periodicals, Inc.

Wallrabe H.,University of Virginia | Sun Y.,ISS, INC. | Svindrych Z.,University of Virginia | Periasamy A.,University of Virginia
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2015

Average lifetime between the usually bi-exponential double-label specimen and a mono-exponential single donor sample serves as a basis for the calculation of the average energy transfer efficiency (E). This semi-quantitative approach however does not fully explore cellular functions, such as endosomal pH differences, specific morphological features, examining sub-populations and the like. We applied a different, quantitative Region-of-Interest (ROI)-based method in 2 live-cell assays by TCSPC FLIM-FRET microscopy: a 5 amino-acid linked FRET standard and mouse pituitary cells expressing a dimerized C/EBPα-bZip transcription factor in the nucleus, both tagged with Cerulean (C) and Venus (V). ROIs with different selection thresholds were generated and compared. Average lifetimes are similar, but ratios between them and other subtle differences are revealed by comprehensive distribution information. Following published references, we also explored 3 different methods to calculate FLIM-FRET energy transfer efficiencies for the Cerulean-Venus constructs, producing differences and supporting the long-held notion that E is called 'apparent' efficiency. FRET's greatest contribution continues to be exploring changes taking place at the cellular level and quantifying differences in relative terms between control and variables. © 2015 SPIE.

Mohan A.,Kansas State University | Hunt M.C.,Kansas State University | Barstow T.J.,Kansas State University | Houser T.A.,Kansas State University | And 2 more authors.
Meat Science | Year: 2010

To determine near-infrared tissue oximeter responses to muscle fibre orientation, display time, and surface colour differences of beef longissimus lumborum steaks, beef loins were cut into steaks either perpendicular or parallel to the muscle fibre orientation. Surface colour differences were created by packaging steaks in vacuum (VAC), 80% O2 and 20% CO2 modified atmosphere packaging (HiOx MAP), polyvinyl chloride film overwrap (PVC), and HiOx MAP converted to PVC (HiOx-PVC) after 2 days. Changes in surface colour and subsurface pigments during display (0, 2, 4, 10, and 15 days at 2 °C) were characterized by using a reflectance-spectrophotometer and a near-infrared tissue oximeter, respectively. Fibre orientation, storage, and packaging affected (P < 0.05) colour, total pigment, deoxymyoglobin, and oxymyoglobin content. Tissue oximetry measurements appear to have potential for real-time monitoring of myoglobin redox forms and oxygen status of packaged meat, but fibre orientation needs to be controlled. © 2009 Elsevier Ltd. All rights reserved.

Mohan A.,Kansas State University | Hunt M.C.,Kansas State University | Barstow T.J.,Kansas State University | Houser T.A.,Kansas State University | Hueber D.M.,ISS, INC.
Food Chemistry | Year: 2010

We investigated the response of frequency-domain multidistance (FDMD) near-infrared (NIR) tissue oximetry for detecting absolute amounts of myoglobin (Mb) redox forms and their relationship to meat colour stability. Four packaging formats were used to create different blends of Mb redox forms and meat colours during display. Changes in surface colour and subsurface pigment forms during simulated display time (0, 2, 4, and 10 d at 2 °C) were evaluated using surface reflecto-spectrophotometry (both L*a*b* and specific wavelengths) and FDMD NIR tissue oximetry. Data for both methods of direct measurement of oxymyoglobin and deoxymyoglobin were strongly related and accounted for 86-94% of the display variation in meat colour. Indirect estimates of metmyoglobin ranged from r2 = 59-85%. It appears that NIR tissue oximetry has potential as a noninvasive, rapid method for the assessment of meat colour traits and may help improve our understanding of meat colour chemistry in post-rigor skeletal muscle. © 2010 Elsevier Ltd. All rights reserved.

Agency: Department of Health and Human Services | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 350.00K | Year: 2010

DESCRIPTION (provided by applicant): ISS Inc. and the Cognitive Neuroimaging Laboratory (CNL) at the University of Illinois propose to develop and construct the prototype of a novel instrument for full-head non-invasive near infrared (NIR) functional imaging of the human brain (which we call Opticortex ). NIR imaging, because of its combination of spatial and temporal resolution, its ability to image both neuronal and hemodynamic activity, and its relatively low cost, complements and enhances current human brain imaging methods, and is particularly useful for the investigation of whole brain cognitive networks and for studies of neurovascular coupling. Opticortex features include: (a) a large number of channels, providing full-head coverage and greater spatial resolution, using up to 128 laser sources and 60 detectors; and (b) programmable multiplexing to allow for adaptive recording montage design. During Phase I, we will explore two further features: (a) multiple simultaneous modulation frequencies to limit channel crosstalk and increase sampling rate; (b) variable modulation frequencies (from 50 to 300 MHz) to optimize S/N, spatial resolution and depth penetration for specific medical applications. The new systems will also include flexible, modular and integrated software for: (a) data acquisition; (b) co-registration of the optical data with anatomical images of the brain; (c) pre-analysis, artifact rejection and/or correction, averaging, image generation, statistical analysis; and (d) interfacing with other brain imaging software. The modular nature of the instrument confers several application and commercialization advantages. For some applications (e.g. infants or region-of-interest recording) a version featuring 32 sources and 15 detectors will be sufficient; yet, such instrument can be upgraded to the full configuration should the need arise, and for research involving full- head studies in adults. PUBLIC HEALTH RELEVANCE: MRI is the technique of choice for imaging functional changes in the brain activity. It is costly (about 3M) and it requires special facilities. Data acquisition time is of the order of 20 minutes and during the registration session the patient is required to stand still inside the measuring body. We propose to build an instrument that is portable (it can be housed in a doctor's office), affordable (less than 500K), insensitive to motion artifacts (suitable for measurements on infants and children). The new frequency-domain instrument, which we call Opticortex, features 128 light sources and 60 detectors; it is intended for the measurement of the fast and slow activities of the entire brain. The Opticortex will launch a novel range of applications in cognitive neurosciences (task related responses in adults, the effect of aging on the sensory cortex, brain development in infants, linguistics) and it will open the door for the investigation of relevant medical applications: as it will selectively probe different depths of the brain, potential applications in the area of stroke recovery and neurosurgery, the study of epilepsy and depression will be within the reach of the medical research community.

Agency: Department of Health and Human Services | Branch: | Program: SBIR | Phase: Phase I | Award Amount: 456.00K | Year: 2012

DESCRIPTION (provided by applicant): ISS Inc., in collaboration with Dr. Franceschini of the Massachusetts General Hospital and Dr. Yodh of the University of Pennsylvania, proposes to develop and construct the prototype of a novel instrument to monitor cerebral oxygen metabolism (CMRO2) that combines a frequency-domain near-infrared tissue oximeter (FDNIRS) and a diffusion correlation spectroscopy (DCS) device. Combining FDNIRS and DCS will enable us to measure cerebral hemoglobin oxygenation (SO2) and an index (BFi) of cerebral blood flow (CBF) to estimate CMRO2. Our clinical collaborators Dr. Ellen Grant of Children's Hospitals in Boston, and Dr. Daniel Licht of Children's Hospital of Philadelphia will advise us on optimizing the device for the neonatal ICU clinical setting. The ability to rapidly an accurately assess cerebral metabolism at bedside in neonates is critical to improving patient management in neonatology. Currently there is no bedside tool that can accurately screen for brain injury, monitor injury evolution or assess response to therapy. Head ultrasounds are notoriously insensitive and nonspecific, EEG serves a complementary role, and MRI is too expensive and time-consuming to be used for screening or monitoring, and involves unnecessary risksof destabilizing critically ill infants who must be transported to the MRI suite. Conventional NIRS oximetry has failed to become a routine clinical tool in neonatology due to the poor sensitivity of SO2 in detecting brain injury hours after the insult,when equilibrium between oxygen delivery and consumption is reestablished. The direct measure of cerebral oxygen utilization we propose to measure with this novel instrument will provide higher sensitivity to detect brain injury and the ability to monitornormal and abnormal brain development. If successful, this device will allow for real-time interventions and thus could improve clinical outcome. Our long-term plans encompass the commercialization of the first FDNIRS/DCS cerebral metabolism monitoring system. In phase I we will build the first commercial prototype, start to develop unified acquisition and data analysis software, and test this new system in phantoms and adult human subjects. We will then perform a pilot study in newborns and compare infantswith seizure activity confirmed by EEG with healthy controls, to validate the hypothesis that a measure of oxygen consumption is better able to diagnose brain damage than measure of hemoglobin oxygenation. While CMRO2 monitoring has been performed previously in a research setting, by combining ISS FDNIRS systems with lab-built DCS instrumentation, these measurements have required highly trained operators and data analysis by optical imaging experts. Our goal is to transform these cumbersome research systems into a more robust turnkey device that will enable medical staff to obtain clinically and relevant measurements at the bedside. After completion of the Phase I portion of the project, we will proceed with Phase II, during which we plan to refine the system and start demonstrating the clinical relevance of our CMRO2 measurements in three hospitals (Brigham and Women's and Children's Hospitals in Boston, and Children's Hospital of Philadelphia with Dr. Daniel Licht). If the plan is accepted in its entirety,we expect to complete development of the FDNIRS/DCS system, which we call MetaOx, within the projected four-year period. PUBLIC HEALTH RELEVANCE: Newborn brain injury causes significant morbidity. The lack of a bedside monitor for newborn brain health is hindering progress in care that could improve neurodevelopmental outcomes. The overall goal of this SBIR is to develop an instrument with which to quantify cerebral oxygen metabolism in at the bedside to be used in neonatal intensive care units. Such a device will have significant clinical utility for assessing cerebral tissue injuy and disease, and to follow response to treatment.

Iss, Inc. | Date: 2014-11-12

Belts for clothing; Coats for men and women; Womens clothing, namely, shirts, dresses, skirts, blouses.

Iss, Inc. | Date: 2015-05-06

Eyewear, namely, sunglasses, eyeglasses and ophthalmic frames and cases therefor; Frames for spectacles and sunglasses; Spectacles and sunglasses; Sunglasses.

Iss, Inc. | Date: 2015-09-01

Cases for watches and clocks; Parts for watches; Watch bands and straps; Watches.

Loading ISS, INC. collaborators
Loading ISS, INC. collaborators