Plethysmographic signals were measured remotely (> 1m) using ambient light and a simple consumer level digital camera in movie mode. Heart respiration rates could be quantified up to several harmonics. Although the green channel featuring strongest plethysmographic signal, corresponding an absorption peak by (oxy-) hemoglobin, red blue channels also contained information. The results show that photo-plethysmography may useful for medical purposes such as characterization of vascular skin...

Journal Article Recursive Partitioning Analysis of Prognostic Factors in Three Radiation Therapy Oncology Group Malignant Glioma Trials Get access Walter J. Curran, Jr, Jr 1Fox Chase Cancer CenterPhiladelphia, Pa * Correspondence to: Jr., M.D., Fox Center, 7701 Burholme Ave., Philadelphia, PA 19111. Search for other works by this author on: Oxford Academic PubMed Google Scholar Charles B. Scott, Scott 2Radiation GroupPhiladelphia, John Horton, Horton 3Eastern Cooperative Group, Moffitt...

Using a low-coherence Michelson interferometer, we measure two-dimensional images of optical birefringence in bovine tendon as function depth. Polarization-sensitive detection the signal formed by interference backscattered light from sample and mirror reference arm give phase delay between that is propagating along fast slow axes birefringent tendon. Images showing change response to laser irradiation are presented. The technique permits rapid noncontact investigation tissue structural...

Recently, the RTOG and ECOG concluded a joint randomized study on malignant gliomas that was in progress for past five years. A total of 626 patients entered this protocol. Sixty-seven percent 535 evaluable have died thus represents preliminary report major clinical trial. The objective to evaluate efficacy after neurosurgery three new treatment options as compared with control radiotherapy alone. four were: (1) radiation; 6000 rad/6–7 weeks whole brain; (2) higher radiation dose; Control...

We have developed a novel phase-resolved optical coherence tomography (OCT) and Doppler (ODT) system that uses phase information derived from Hilbert transformation to image blood flow in human skin with fast scanning speed high velocity sensitivity. Using the change between sequential scans construct flow-velocity imaging, this technique decouples spatial resolution sensitivity images increases imaging by more than 2 orders of magnitude without compromising or The minimum can be detected an...

We report the development of an optical technique for noninvasive imaging in vivo blood flow dynamics and tissue structures with high spatial resolution (2-10 microm) biological systems. The is based on Doppler tomography (ODT), which combines velocimetry coherence to measure velocity at discrete locations. exceptionally ODT permits both microcirculation surrounding vessel, has significance biomedical research clinical applications. Tomographic chick chorioallantoic membrane rodent skin demonstrated.

Metformin, one of the most commonly used drugs for treatment type II diabetes, was recently found to exert its therapeutic effects, at least in part, by activating AMP-activated protein kinase (AMPK). However, site action, as well mechanism activate AMPK, remains elusive. Here we report how metformin activates AMPK. In cultured bovine aortic endothelial cells, dose-dependently activated AMPK parallel with increased detection reactive nitrogen species (RNS). Further, either depletion...

An optical Doppler tomography (ODT) system that permits imaging of fluid flow velocity in highly scattering media is described. ODT combines velocimetry with the high spatial resolution low-coherence interferometry to measure at discrete locations. Tomographic particle within a circular conduit submerged 1 mm below surface phantom Intralipid demonstrated.

<b>Objective: </b> To determine if excessive daytime sleepiness (EDS) can predate future Parkinson disease (PD). <b>Methods: EDS was assessed in 3,078 men aged 71 to 93 years the Honolulu-Asia Aging Study from 1991 1993. All were free of prevalent PD and dementia. Follow-up for incident based on three repeat neurologic assessments 1994 2001. <b>Results: During course follow-up, 43 developed (19.9/10,000 person-years). After age adjustment, there more than a threefold excess risk with vs...

In optical coherence tomography, axial and lateral resolutions are determined by the source length numerical aperture of sampling lens, respectively. Whereas resolution can be improved use a broadband light source, there is trade-off between focusing depth when conventional elements used. We report on incorporation an axicon lens into sample arm interferometer to overcome this limitation. Using with top angle 160°, we maintained 10‐µm or better over at least 6 mm. addition having high...

The clinical objective in the treatment of a patient with port-wine stain (PWS) undergoing laser therapy is to maximize thermal damage PWS, while at same time minimizing nonspecific injury normal overlying epidermis. With dynamic cooling, epidermis can be cooled selectively. When cryogen spurt applied skin surface for an appropriately short period (on order tens milliseconds), cooling remains localized epidermis, leaving temperature deeper PWS vessels unchanged.Comparative measurements...

A high-speed single-mode fiber–based polarization-sensitive optical coherence tomography (PS OCT) system was developed. With a polarization modulator, Stokes parameters of reflected flight for four input states are measured as function depth. phase modulator in the reference arm Michelson interferometer permits independent control axial scan rate and carrier frequency. In vivo PS OCT images human skin presented, showing subsurface structures that not discernible conventional images....

The plane-wave pseudopotential method is used to calculate structural properties for wurtzite and zinc-blende AlN InN using large basis sets treating the indium 4d electrons as valence. These calculations, together with corresponding ones GaN [A. F. Wright J. S. Nelson, Phys. Rev. B 50, 2159 (1994)], yield a consistent set of well-converged AlN, GaN, InN. In particular, measured lattice mismatch among these compounds---essential an accurate description alloy properties---is well reproduced.

Surgical specimens of malignant, supratentorial, astrocytic gliomas from 503 patients randomized on an RTOG-ECOG treatment protocol were examined by central pathologic review. The diagnosis glioblastoma multiforme (GBM) was made only when one or more foci coagulation necrosis involving tumor cells identified histologically. Malignant neoplasms without classified as astrocytoma with atypical anaplastic features (AAF). median survival stratifying for GBM eight months compared to 28 AAF. In...

Polarization-sensitive optical coherence tomography (PS-OCT) was used to characterize completely the polarization state of light backscattered from turbid media. Using a low-coherence source, one can determine Stokes parameters as function path in To demonstrate application this technique we determined birefringence and axis fibrous tissue (rodent muscle) vivo rodent skin. PS-OCT has potentially useful applications biomedical optics by imaging simultaneously structural properties biological...

The <i>Journal of Biomedical Optics</i> (JBO) is a Gold Open Access journal that publishes peer-reviewed papers on the use novel optical systems and techniques for improved health care biomedical research.

Abstract— Among the sequence of events which occur during photodynamic therapy (PDT) are depletion oxygen and disruption tumor blood flow. In order to more clearly understand these phenomena we have utilized transcutaneous electrodes monitor tissue disappearance. These results provide, for first time, non‐invasive real‐time information regarding influence light dose on oxygenation irradiation. Measurements were conducted transplanted VX‐2 skin carcinomas grown in ears New Zealand white...

We used a novel phase-resolved optical Doppler tomographic (ODT) technique with very high flow-velocity sensitivity 10 µm/s and spatial resolution µm to image blood flow in port-wine stain (PWS) birthmarks human skin. In addition the regular ODT velocity structural images, we use variance of map PWS vessels. Our device combines therapeutic systems such that can be monitored situ before after laser treatment. To authors’ knowledge this is first clinical application provide fast...

Background: Cryogen spray cooling can be used to provide epidermal protection while still achieving spatially selective photocoagulation in the upper dermis.The objective of this study is determine efficacy and safety cryogen combination with a nonablative Nd:YAG ( = 1320 nm) laser treatment facial rhytides human volunteers.Observations: Thirty-five adults bilateral periorbital were treated 3 treatments performed sequentially at intervals 2 weeks.Small but statistically significant...