Read by QxMD icon Read

Near-infrared spectroscopy

Jia Zhao, Jiangang Liu, Xin Jiang, Guifei Zhou, Guowei Chen, Xiao P Ding, Genyue Fu, Kang Lee
Executive function (EF) plays vital roles in our everyday adaptation to the ever-changing environment. However, limited existing studies have linked EF to the resting-state brain activity. The functional connectivity in the resting state between the sub-regions of the brain can reveal the intrinsic neural mechanisms involved in cognitive processing of EF without disturbance from external stimuli. The present study investigated the relations between the behavioral executive function (EF) scores and the resting-state functional network topological properties in the Prefrontal Cortex (PFC)...
2016: Frontiers in Neuroscience
Manuel E Hernandez, Roee Holtzer, Gioella Chaparro, Kharine Jean, Julia M Balto, Brian M Sandroff, Meltem Izzetoglu, Robert W Motl
Mobility and cognitive impairments are common in persons with multiple sclerosis (MS), and are expected to worsen with increasing age. However, no studies, to date, in part due to limitations of conventional neuroimaging methods, have examined changes in brain activation patterns during active locomotion in older patients with MS. This study used functional Near Infrared Spectroscopy (fNIRS) to evaluate real-time neural activation differences in the pre-frontal cortex (PFC) between middle-aged to older adults with MS and healthy controls during single (Normal Walk; NW) and dual-task (Walking While Talking; WWT) locomotion tasks...
November 15, 2016: Journal of the Neurological Sciences
Tao Li, Xiufen Chen, Yajun Liu, Lulu Fan, Liqing Lin, Yu Xu, Sijia Chen, Jingwei Shao
Ursolic acid (UA) as a nature product exhibits good anti-cancer activity, low toxicity, and good liver protection features. However, the low-solubility and poor bioavailability restrict its further clinical application. To overcome this problem, a pH-sensitive prodrug delivery system (UA@MSN-UA) that incorporated acid-sensitive linkage between drug and silica-based mesoporous nanosphere (MSN) was successfully designed and synthesized. The physicochemical properties of the UA@MSN-UA nanoparticles were investigated for shape, particle size, zeta potential, nitrogen adsorption-desorption and infrared (IR) spectroscopy...
October 19, 2016: European Journal of Pharmaceutical Sciences
Tomasz Czaja, Sylwester Mazurek, Roman Szostak
Diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) is a fast, reliable and cost effective analytical method, requiring minimal or no sample preparation. It is commonly used in the course of qualitative and quantitative analysis of pharmaceutical ingredients and food. We demonstrate that simpler and cheaper specular reflectance (SR) accessory working in a DRIFTS like mode (SR-DL) can be an alternative for DIRFTS attachment. An application of a modified SR accessory for quantitative analysis of solids samples is presented...
December 1, 2016: Talanta
Yanying Wang, Xiangyang Yu, Xiaoxue Ye, Kangbing Wu, Tsunghsueh Wu, Chunya Li
Gold nanorods (AuNRs) integrated with ZnCdHgSe near-infrared quantum dots (AuNRs-ZnCdHgSe QDs) were successfully synthesized and characterized by transmission electron microscope, X-ray photoelectron spectroscopy, and X-ray diffraction. A glassy carbon electrode was decorated with the aforementioned AuNRs-ZnCdHgSe QDs nanocomposite, which provides a biocompatible interface for the subsequent immobilization of prostate specific antibody (anti-PSA). After being successively treated with glutaraldehyde vapor and bovine serum albumin solution, a photoelectrochemical immunosensing platform based on anti-PSA/AuNRs-ZnCdHgSe QDs/GCE was established...
November 2, 2016: Analytica Chimica Acta
Maggy T Sikulu-Lord, Masabho P Milali, Michael Henry, Robert A Wirtz, Leon E Hugo, Floyd E Dowell, Gregor J Devine
Estimating the age distribution of mosquito populations is crucial for assessing their capacity to transmit disease and for evaluating the efficacy of available vector control programs. This study reports on the capacity of the near-infrared spectroscopy (NIRS) technique to rapidly predict the ages of the principal dengue and Zika vector, Aedes aegypti. The age of wild-type males and females, and males and females infected with wMel and wMelPop strains of Wolbachia pipientis were characterized using this method...
October 2016: PLoS Neglected Tropical Diseases
Abdul K Parchur, Qifei Li, Anhong Zhou
We report the synthesis, characterization, and application of Prussian blue (PB) functionalized CaMoO4:Eu@SiO2@Au nanorod hybrid nanoparticles (HNPs), with multimodal capabilities such as fluorescence imaging, surface-enhanced Raman spectroscopy (SERS) detection and photothermal therapy (PTT). The average size of CaMoO4:Eu@SiO2 NPs was 206 nm. The HNPs are highly dispersible in water for several weeks without settling and show a strong absorption in the near-infrared region, overlapping with the PB absorption between 600 nm and 1000 nm and the surface plasmon resonance of Au nanorods around 800 nm...
October 21, 2016: Biomaterials Science
Aram Hong, Heeseon Jang, Changseop Jeong, Myoung Choul Choi, Jiyoung Heo, Nam Joon Kim
We obtained resonant two-photon ionization circular dichroism (R2PICD) spectra of jet-cooled phenylalanine (Phe) and its hydrated clusters (Phe(H2O)n, n=1-2) near the origin band of the S0-S1 transition. The R2PICD spectra of Phe exhibit well-resolved CD bands of six different conformers present in the jet, which vary in sign and magnitude depending on their conformations. We revised the previous structural assignments of the Phe conformers based on the comparison between the experimental and theoretical CD signs, infrared spectra, and rotational band contours...
October 21, 2016: Journal of Physical Chemistry Letters
Victor M Niemeijer, Ruud F Spee, Thijs Schoots, Pieter F F Wijn, Hareld M Kemps
The extent and speed of transient skeletal muscle deoxygenation during exercise onset in chronic heart failure (CHF) patients is related to impairments of local O2 delivery and utilization. This study examined the physiological background of submaximal exercise performance in 19 moderately impaired CHF patients (Weber class A, B, and C) compared with 19 matched healthy control (HC) subjects by measuring skeletal muscle oxygenation (SmO2) changes during cycling exercise. All subjects performed two subsequent moderate-intensity 6-minute exercise tests (bout 1 and 2) with measurements of pulmonary oxygen uptake kinetics, and SmO2 using near infrared (NIR) spatially resolved spectroscopy (SRS) at the vastus lateralis for determination of absolute oxygenation values, amplitudes, kinetics (mean response time for onset), and deoxygenation overshoot characteristics...
October 7, 2016: American Journal of Physiology. Heart and Circulatory Physiology
Klaus Kopitzki, Andreas Oldag, Catherine M Sweeney-Reed, Judith Machts, Maria Veit, Jörn Kaufmann, Hermann Hinrichs, Hans-Jochen Heinze, Katja Kollewe, Susanne Petri, Bahram Mohammadi, Reinhard Dengler, Andreas R Kupsch, Stefan Vielhaber
PURPOSE: Aim of the present study was to investigate potential impairment of non-motor areas in amyotrophic lateral sclerosis (ALS) using near-infrared spectroscopy (NIRS) and diffusion tensor imaging (DTI). In particular, we evaluated whether homotopic resting-state functional connectivity (rs-FC) of non-motor associated cortical areas correlates with clinical parameters and disease-specific degeneration of the corpus callosum (CC) in ALS. MATERIAL AND METHODS: Interhemispheric homotopic rs-FC was assessed in 31 patients and 30 healthy controls (HCs) for 8 cortical sites, from prefrontal to occipital cortex, using NIRS...
2016: NeuroImage: Clinical
Victoria A McCredie, Simone Piva, Marlene Santos, Wei Xiong, Airton Leonardo de Oliveira Manoel, Andrea Rigamonti, Gregory M T Hare, Martin G Chapman, Andrew J Baker
BACKGROUND: There are a range of opinions on the benefits and thresholds for the transfusion of red blood cells in critically ill patients with traumatic brain injury (TBI) and an urgent need to understand the neurophysiologic effects. The aim of this study was to examine the influence of red blood cell transfusions on cerebral tissue oxygenation (SctO2) in critically ill TBI patients. METHODS: This prospective observational study enrolled consecutive TBI patients with anemia requiring transfusion...
October 18, 2016: Neurocritical Care
Emily Cohen, Laura Dix, Willem Baerts, Thomas Alderliesten, Petra Lemmers, Frank van Bel
BACKGROUND: A haemodynamically significant patent ductus arteriosus (hsPDA) reduces cerebral oxygenation in appropriate-for-gestational-age (AGA) preterm neonates. Reduced cerebral oxygenation has been associated with brain injury. Preterm small-for-gestational-age (SGA) neonates show higher cerebral oxygenation than AGA peers throughout the first postnatal days. To date, no studies have investigated the effect of hsPDA on cerebral oxygenation in preterm SGA neonates. OBJECTIVE: We aimed to assess the effect of hsPDA on cerebral oxygenation in preterm SGA neonates compared to AGA peers...
October 19, 2016: Neonatology
Thomas P J Blaikie, John Howard Couper, Gus Hancock, Philip L Hurst, Robert Peverall, Graham Richmond, Grant A D Ritchie, David Taylor, Kevin Valentine
A portable and compact device is demonstrated for measuring acetone in breath samples. The device features a 7 cm long high finesse optical cavity as an optical sensor that is coupled to a miniature adsorption preconcentrator containing 0.5 g of polymer material. Acetone is trapped out of breath and released into the optical cavity where it is probed by a near-infrared diode laser operating at ~1670 nm. With an optical cavity mirror reflectivity of 99.994 % a limit of detection of 159 ppbv (1σ) is demonstrated on samples from breath bags...
October 18, 2016: Analytical Chemistry
Rebecca Re, Edoardo Martinenghi, Alberto Dalla Mora, Davide Contini, Antonio Pifferi, Alessandro Torricelli
We report the development of a compact probe for time-domain (TD) functional near-infrared spectroscopy (fNIRS) based on a fast silicon photomultiplier (SiPM) that can be put directly in contact with the sample without the need of optical fibers for light collection. We directly integrated an avalanche signal amplification stage close to the SiPM, thus reducing the size of the detection channel and optimizing the signal immunity to electromagnetic interferences. The whole detection electronics was placed in a plastic screw holder compatible with the electroencephalography standard cap for measurement on brain or with custom probe holders...
October 2016: Neurophotonics
Lin Li, Mary Cazzell, Olajide Babawale, Hanli Liu
Atlas-guided diffuse optical tomography (atlas-DOT) is a computational means to image changes in cortical hemodynamic signals during human brain activities. Graph theory analysis (GTA) is a network analysis tool commonly used in functional neuroimaging to study brain networks. Atlas-DOT has not been analyzed with GTA to derive large-scale brain connectivity/networks based on near-infrared spectroscopy (NIRS) measurements. We introduced an automated voxel classification (AVC) method that facilitated the use of GTA with atlas-DOT images by grouping unequal-sized finite element voxels into anatomically meaningful regions of interest within the human brain...
October 2016: Neurophotonics
Roberto A DE Blasi, Roberto Arcioni, Domitilla Brancadoro, Monica Rocco
BACKGROUND: Even though fluid loading is thought to improve organ perfusion, the way in which it does so remains unclear. We assessed how the microvascular bed in skeletal muscle reacts to passive leg raising in patients with and without sepsis or septic shock. METHODS: We studied 40 critically ill patients (group A) and 30 healthy controls (group B). The forearm microvascular bed was assessed using near-infrared spectroscopy before and after passive leg raising...
October 2016: Minerva Anestesiologica
Masahiro Horiuchi, Yoko Handa, Daijiro Abe, Yoshiyuki Fukuoka
We measured oxygen consumption during walking per unit distance (Cw) values for 12 human healthy young males at six speeds from 0.667 to 1.639 m s(-1) (four min per stage) on a level gradient under normobaric normoxia, moderate hypoxia (15% O2), and severe hypoxia (11% O2). Muscle deoxygenation (HHb) was measured at the vastus lateralis muscle using near-infrared spectroscopy. Economical speed which can minimize the Cw in each individual was calculated from a U-shaped relationship. We found a significantly slower economical speed (ES) under severe hypoxia [1...
October 15, 2016: Biology Open
Shota Nishitani, Kazuya Ikematsu, Tsunehiko Takamura, Sumihisa Honda, Koh-Ichiro Yoshiura, Kazuyuki Shinohara
There is extensive evidence in animal studies, particularly in vole species (Microtus), that oxytocin (OT) receptor and arginine-vasopressin (AVP) receptor 1a is critical for the regulation of maternal and paternal behavior, respectively. Human studies have gained insight into the relationship between both hormone receptor gene variants and behavior, but not between the variants and the underlying brain activity. To study this, we investigated the association between neural activation of the anterior prefrontal cortex (APFC) in mothers and fathers in response to their child smiling video stimuli to induce the positive affect related to attachment with their child, and genetic variants of OT receptor (OXTR) and AVP receptor 1A (AVPR1A)...
October 12, 2016: Hormones and Behavior
Kana Iwakuni, Sho Okubo, Koichi M T Yamada, Hajime Inaba, Atsushi Onae, Feng-Lei Hong, Hiroyuki Sasada
We demonstrate that dual-comb spectroscopy, which allows one to record broadband spectra with high frequency accuracy in a relatively short time, provides a real advantage for the observation of pressure-broadening and pressure-shift effects. We illustrate this with the ν_{1}+ν_{3} vibration band of ^{12}C_{2}H_{2}. We observe transitions from P(26) to R(29), which extend over a 3.8 THz frequency range, at six pressures ranging up to 2654 Pa. Each observed absorption line profile is fitted to a Voigt function yielding pressure-broadening and pressure-shift coefficients for each rotation-vibration transition...
September 30, 2016: Physical Review Letters
Maja Turinek, Martina Bavec, Milan Repič, Matjaž Turinek, Andreja Urbanek Krajnc, Christian Moellers, Alba Tres, Franc Bavec
BACKGROUND: Organic production is widely assumed to affect quality and nutritional parameters of arable crops. A field experiment was started in 2009 following integrated (INT), organic (ORG) and biodynamic (BD) production standards for wheat, maize and rapeseed production. With resort to standard analytical procedures and chemometrics compositional parameters of Brassica napus L. 'Siska' seed (water, protein, oil and glucosinolate content) by non-destructive near-infrared spectroscopy (NIRS), and fatty acid composition determined by gas chromatography, were assessed...
October 14, 2016: Journal of the Science of Food and Agriculture
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"