keyword
MENU ▼
Read by QxMD icon Read
search

laser doppler

keyword
https://www.readbyqxmd.com/read/27913807/determination-of-a-threshold-compromise-value-for-the-perfusion-index-by-laser-doppler-imaging-after-digital-revascularization
#1
Y-Y Chu, D-Y Yu, C-W Chang, F Fang, H-T Liao
: We have used laser Doppler imaging to monitor the microcirculation of replanted digits during the post-operative period in 103 patients who underwent either replantation after traumatic amputation or toe-to-finger reconstruction. The blood flow (perfusion unit) in each revascularized digit was compared with that of an unaffected digit. The perfusion index was defined as the perfusion value of a revascularized digit divided by the perfusion value of the neighbouring normal digit. The ideal threshold value of the perfusion index (0...
December 1, 2016: Journal of Hand Surgery, European Volume
https://www.readbyqxmd.com/read/27910698/laser-induced-fluorescence-measurements-of-axial-velocity-velocity-shear-and-parallel-ion-temperature-profiles-during-the-route-to-plasma-turbulence-in-a-linear-magnetized-plasma-device
#2
S Chakraborty Thakur, K Adriany, J J Gosselin, J McKee, E E Scime, S H Sears, G R Tynan
We report experimental measurements of the axial plasma flow and the parallel ion temperature in a magnetized linear plasma device. We used laser induced fluorescence to measure Doppler resolved ion velocity distribution functions in argon plasma to obtain spatially resolved axial velocities and parallel ion temperatures. We also show changes in the parallel velocity profiles during the transition from resistive drift wave dominated plasma to a state of weak turbulence driven by multiple plasma instabilities...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910678/first-results-from-the-thomson-scattering-diagnostic-on-proto-mpex
#3
T M Biewer, S Meitner, J Rapp, H Ray, G Shaw
A Thomson scattering (TS) diagnostic has been successfully implemented on the prototype Material Plasma Exposure eXperiment (Proto-MPEX) at Oak Ridge National Laboratory. The diagnostic collects the light scattered by plasma electrons and spectroscopically resolves the Doppler shift imparted to the light by the velocity of the electrons. The spread in velocities is proportional to the electron temperature, while the total number of photons is proportional to the electron density. TS is a technique used on many devices to measure the electron temperature (Te) and electron density (ne) of the plasma...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27910351/calibration-of-the-ohrex-high-resolution-imaging-crystal-spectrometer-at-the-livermore-electron-beam-ion-traps
#4
N Hell, P Beiersdorfer, E W Magee, G V Brown
We report the calibration of the Orion High-Resolution X-ray (OHREX) imaging crystal spectrometer at the EBIT-I electron beam ion trap at Livermore. Two such instruments, dubbed OHREX-1 and OHREX-2, are fielded for plasma diagnostics at the Orion laser facility in the United Kingdom. The OHREX spectrometer can simultaneously house two spherically bent crystals with a radius of curvature of r = 67.2 cm. The focusing properties of the spectrometer allow both for larger distance to the source due to the increase in collected light and for observation of extended sources...
November 2016: Review of Scientific Instruments
https://www.readbyqxmd.com/read/27903483/therapeutic-benefits-and-adverse-effects-of-combined-pro-angiogenic-gene-therapy-in-mouse-critical-leg-ischemia
#5
Benoît Lebas, Julien Galley, Edith Renaud-Gabardos, Françoise Pujol, Françoise Lenfant, Barbara Garmy-Susini, Xavier Chaufour, Anne-Catherine Prats
OBJECTIVE: Critical leg ischemia (CLI) represents the ultimate stage of peripheral arterial disease. Despite current surgery advances, patients with CLI have limited therapeutic options. Therapeutic angiogenesis thus appears as a powerful approach, aiming to stimulate vessel formation by angiogenic molecules administration. In this context, combined gene therapy has proved the most efficient. The present study aims to compare, in a preclinical mouse model, the therapeutic benefit of a combination of two angiogenic factors FGF2 (fibroblast growth factor 2) and Cyr61 using plasmid and viral vectors, able to generate short or long-term transgene expression in the leg, respectively...
November 26, 2016: Annals of Vascular Surgery
https://www.readbyqxmd.com/read/27899298/mechanisms-and-time-course-of-menthol-induced-cutaneous-vasodilation
#6
Daniel H Craighead, Nathaniel B McCartney, James H Tumlinson, Lacy M Alexander
Menthol is a vasoactive compound that is widely used in topical analgesic agents. Menthol induces cutaneous vasodilation, however the underlying mechanisms are unknown. Determining the rates of appearance and clearance of menthol in the skin is important for optimizing topical treatment formulation and dosing. The purpose of this study was to determine the mechanisms contributing to menthol-mediated cutaneous vasodilation and to establish a time course for menthol appearance/clearance in the skin. Ten young (23±1years, 5 males 5 females) subjects participated in two protocols...
November 26, 2016: Microvascular Research
https://www.readbyqxmd.com/read/27896221/microvascular-blood-flow-improvement-in-hyperglycemic-obese-adult-patients-by-hypocaloric-diet
#7
T Mastantuono, M Di Maro, M Chiurazzi, L Battiloro, N Starita, G Nasti, D Lapi, L Iuppariello, M Cesarelli, G D'Addio, A Colantuoni
The present study was aimed to assess the changes in skin microvascular blood flow (SBF) in newly diagnosed hyperglycemic obese subjects, administered with hypocaloric diet. Adult patients were recruited and divided in three groups: NW group (n=54), NG (n=54) and HG (n=54) groups were constituted by normal weight, normoglycemic and hyperglycemic obese subjects, respectively. SBF was measured by laser Doppler perfusion monitoring technique and oscillations in blood flow were analyzed by spectral methods under baseline conditions, at 3 and 6 months of dietary treatment...
November 2016: Translational Medicine @ UniSa
https://www.readbyqxmd.com/read/27896001/long-range-wide-field-swept-source-optical-coherence-tomography-with-gpu-accelerated-digital-lock-in-doppler-vibrography-for-real-time-in-vivo-middle-ear-diagnostics
#8
Dan MacDougall, Joshua Farrell, Jeremy Brown, Manohar Bance, Robert Adamson
We present the design, implementation and validation of a swept-source optical coherence tomography (OCT) system for real-time imaging of the human middle ear in live patients. Our system consists of a highly phase-stable Vernier-tuned distributed Bragg-reflector laser along with a real-time processing engine implemented on a graphics processing unit. We use the system to demonstrate, for the first time in live subjects, real-time Doppler measurements of middle ear vibration in response to sound, video rate 2D B-mode imaging of the middle ear and 3D volumetric B-mode imaging...
November 1, 2016: Biomedical Optics Express
https://www.readbyqxmd.com/read/27894154/perfusion-controlled-mobilization-after-lower-extremity-free-flaps-pushing-the-limits-of-time-and-intensity
#9
Ulf Dornseifer, Charlotte Kleeberger, Lukas Kargl, Markus Schönberger, Daniel Rohde, Milomir Ninkovic, Arndt Schilling
Background The current standard to gradually adapt the fragile perfusion in lower extremity free flaps to an upright posture is the dangling maneuver. This type of flap training neither fits the orthostatic target load of an upright posture, nor does it assist in mobilizing the patients effectively. In this study, we quantitatively analyzed training effects of an early and full mobilization on flap perfusion. Methods A total of 15 patients with gracilis flaps for distal lower extremity reconstruction were included...
November 28, 2016: Journal of Reconstructive Microsurgery
https://www.readbyqxmd.com/read/27891612/neurovascular-mechanisms-underlying-augmented-cold-induced-reflex-cutaneous-vasoconstriction-in-human-hypertension
#10
Jody L Greaney, W Larry Kenney, Lacy M Alexander
Despite ample evidence of dysregulated sympathetic control of the peripheral vasculature in hypertension, no studies have examined integrated neurovascular function during cold stress in hypertensive adults (HTN). We hypothesized that (1) whole-body cooling would elicit greater cutaneous vasoconstriction and greater increases in skin sympathetic nervous system activity (SSNA) in HTN (n = 14; 56 ± 2 yrs) compared to age-matched normotensive adults (NTN; n = 14; 55 ± 2 yrs) and (2) augmented reflex vasoconstriction in HTN would be mediated by an increase in cutaneous vascular adrenergic sensitivity and a greater contribution of non-adrenergic sympathetic co-transmitters...
November 28, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27885499/the-effects-of-alpha-1-adrenoceptor-blockade-and-angiotensin-converting-enzyme-inhibition-on-central-and-brachial-blood-pressure-and-vascular-reactivity-the-doxazosin-ramipril-study
#11
Andreas Jekell, Majid Kalani, Thomas Kahan
We aimed to study whether inhibition of the renin-angiotensin-aldosterone system has effects on vascular structure and function beyond the effects on blood pressure reduction alone. Patients with mild-to-moderate hypertension (n = 61, age 54 ± 12 years, 34% women) received the angiotensin converting enzyme inhibitor ramipril 10 mg or the alpha 1-adrenoceptor blocker doxazosin 8 mg double-blind for 12 weeks. Aortic blood pressure, pulse wave velocity, and augmentation index were assessed by applanation tonometry...
November 24, 2016: Heart and Vessels
https://www.readbyqxmd.com/read/27884327/inhibition-of-c-jun-n-terminal-kinase-signaling-suppresses-skin-flap-apoptosis-in-a-rat-ischemia-and-or-reperfusion-model
#12
Ming Bai, Yifang Liu, Dechang Yin, Mingzi Zhang, Youbin Wang, Xuemei Ma, Yunqi Liu, Pengxiang Zhao
BACKGROUND: The goals of this study were to validate the role of c-Jun N-terminal kinase (JNK) activation in skin flap apoptosis in a rat model of abdomen skin ischemia and/or reperfusion (IR) and to compare the protective effect of SP600125 and hydrogen-rich saline in skin IR injury. METHODS: Male Sprague-Dawley rats were divided into five groups: one sham surgery group and four surgery groups. Before undergoing 3 h of IR management, the surgery groups were treated with normal saline (IR), dimethyl sulfoxide, SP600125 (SP), and hydrogen-rich saline (H)...
December 2016: Journal of Surgical Research
https://www.readbyqxmd.com/read/27869797/the-receptor-for-advanced-glycation-end-products-impairs-collateral-formation-in-both-diabetic-and-non-diabetic-mice
#13
Laura M Hansen, Divya Gupta, Giji Joseph, Daiana Weiss, W Robert Taylor
Diabetics often have poor perfusion in their limbs as a result of peripheral artery disease and an impaired ability to generate collateral vessels. The receptor for advanced glycation end products (RAGE) is one protein that is thought to play a detrimental role in collateral development in diabetics due to increased levels of advanced glycation end products (AGE), one of its ligands, in diabetes. Thus, the aim of this study was to investigate the role of RAGE in both diabetic and non-diabetic settings in a model of collateral formation in mice...
November 21, 2016: Laboratory Investigation; a Journal of Technical Methods and Pathology
https://www.readbyqxmd.com/read/27868242/assessment-of-macrovascular-endothelial-function-using-pulse-wave-analysis-and-its-association-with-microvascular-reactivity-in-healthy-subjects
#14
N N I N Ibrahim, A H G Rasool
BACKGROUND: Pulse wave analysis (PWA) and laser Doppler fluximetry (LDF) are non-invasive methods of assessing macrovascular endothelial function and microvascular reactivity respectively. The aim of this study was to assess the correlation between macrovascular endothelial function assessed by PWA and microvascular reactivity assessed by LDF. METHOD: 297 healthy and non-smoking subjects (159 females, mean age (±SD) 23.56 ± 4.54 years) underwent microvascular reactivity assessment using LDF followed by macrovascular endothelial function assessments using PWA...
November 20, 2016: Skin Research and Technology
https://www.readbyqxmd.com/read/27863636/the-effect-of-propofol-infusion-with-topical-epinephrine-on-cochlear-blood-flow-and-hearing-an-experimental-study
#15
Chul Ho Jang, Yong Beom Cho, Jun Sik Lee, Geun Hyung Kim, Won-Kyo Jung, Sok Cheon Pak
BACKGROUND AND OBJECTIVE: Propofol is the most commonly used intravenous (IV) anesthetic agent and is associated with hypotension upon induction of anesthesia. Intravenous propofol infusion has several properties that may be beneficial to patients undergoing middle ear surgery. Topical application of concentrated epinephrine is a valuable tool for achieving hemostasis in the middle ear and during mastoid surgery. The purpose of the present study was to determine the effects of propofol infusion with topical epinephrine on cochlear blood flow (CBF) and hearing in rats...
December 2016: International Journal of Pediatric Otorhinolaryngology
https://www.readbyqxmd.com/read/27861895/effects-of-postural-change-from-supine-to-head-up-tilt-on-skin-sympathetic-nerve-activity-component-synchronised-with-cardiac-cycle-in-warmed-men
#16
Yu Ogawa, Yoshi-Ichiro Kamijo, Shigeki Ikegawa, Shizue Masuki, Hiroshi Nose
In humans, the cutaneous vasodilatation response to hyperthermia has been suggested to be suppressed by baroreflexes to maintain arterial pressure when the posture was changed from supine to upright, and if the reflexes do not function sufficiently, it can cause heat syncope. However, the efferent signals of the reflexes have not been identified. To identify the signals, we continuously measured skin sympathetic nerve activity (SSNA; microneurography), right atrial volume (RAV; echocardiography, the baroreceptors for the reflexes are reportedly located), cutaneous vascular conductance on the chest (CVCchest ; laser Doppler flowmetry), and oesophageal temperature (Toes ; thermocouple) in young men before and after passive warming with a perfusion suit, during which periods the posture was changed from supine to 30° head-up tilt positions...
November 8, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27859929/does-attenuated-skin-blood-flow-lower-sweat-rate-and-the-critical-environmental-limit-for-heat-balance-during-severe-heat-exposure
#17
Matthew N Cramer, Daniel Gagnon, Craig G Crandall, Ollie Jay
Attenuated skin blood flow (SkBF) is often assumed to impair core temperature (Tc ) regulation. Profound pharmacologically-induced reductions in SkBF (∼85%) lead to impaired sweating but whether the smaller attenuations in SkBF (∼20%) more associated with ageing and certain diseases lead to decrements in sweating and maximum heat loss potential is unknown. Seven healthy males (28 ± 4y) completed a 30-min equilibration period at 41°C and a vapour pressure (Pa ) of 2.57 kPa followed by incremental steps in Pa of 0...
November 11, 2016: Experimental Physiology
https://www.readbyqxmd.com/read/27857289/use-of-photoacoustic-excitation-and-laser-vibrometry-to-remotely-detect-trace-explosives
#18
C M Wynn, R W Haupt, J H Doherty, R R Kunz, W Bai, G Diebold
In this paper, we examine a laser-based approach to remotely initiate, measure, and differentiate acoustic and vibrational emissions from trace quantities of explosive materials against their environment. Using a pulsed ultraviolet laser (266 nm), we induce a significant (>100  Pa) photoacoustic response from small quantities of military-grade explosives. The photoacoustic signal, with frequencies predominantly between 100 and 500 kHz, is detected remotely via a wideband laser Doppler vibrometer. This two-laser system can be used to rapidly detect and discriminate explosives from ordinary background materials, which have significantly weaker photoacoustic response...
November 10, 2016: Applied Optics
https://www.readbyqxmd.com/read/27855988/development-of-a-platelet-adhesion-transport-equation-for-a-computational-thrombosis-model
#19
Joshua O Taylor, Ling Yang, Steven Deutsch, Keefe B Manning
Thrombosis is a significant issue for cardiovascular device development and use. While thrombosis models are available, very few are device-related and none have been thoroughly validated experimentally. Here, we introduce a surface adherent platelet transport equation into a continuum model to account for the biomaterial interface/blood interaction. Using a rotating disc system and polyurethane-urea material, we characterize steady and pulsatile flow fields using laser Doppler velocimetry. In vitro measurements of platelet adhesion are used in combination with the LDV data to provide further experimental validation...
November 10, 2016: Journal of Biomechanics
https://www.readbyqxmd.com/read/27847966/therapeutic-potential-of-pro-angiogenic-bpc157-is-associated-with-vegfr2-activation-and-up-regulation
#20
Ming-Jer Hsieh, Hsien-Ta Liu, Chao-Nin Wang, Hsiu-Yun Huang, Yuling Lin, Yu-Shien Ko, Jong-Shyan Wang, Vincent Hung-Shu Chang, Jong-Hwei S Pang
: BPC 157, a pentadecapeptide with extensive healing effects, has recently been suggested to contribute to angiogenesis. However, the underlying mechanism is not yet clear. The present study aimed to explore the potential therapeutic effect and pro-angiogenic mechanism of BPC 157. As demonstrated by the chick chorioallantoic membrane (CAM) assay and endothelial tube formation assay, BPC 157 could increase the vessel density both in vivo and in vitro, respectively. BPC 157 could also accelerate the recovery of blood flow in the ischemic muscle of the rat hind limb as detected by laser Doppler scanning, indicating the promotion of angiogenesis...
November 15, 2016: Journal of Molecular Medicine: Official Organ of the "Gesellschaft Deutscher Naturforscher und Ärzte"
keyword
keyword
32980
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"