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https://www.readbyqxmd.com/read/28805589/visual-dysfunction-in-parkinson-s-disease
#1
Richard A Armstrong
This chapter describes the visual problems likely to be encountered in Parkinson's disease (PD) and whether such signs are useful in differentiating the parkinsonian syndromes. Visual dysfunction in PD may involve visual acuity, contrast sensitivity, color discrimination, pupil reactivity, saccadic and pursuit eye movements, motion perception, visual fields, and visual processing speeds. In addition, disturbance of visuospatial orientation, facial recognition problems, rapid eye movement (REM) sleep behavior disorder, and chronic visual hallucinations may be present...
2017: International Review of Neurobiology
https://www.readbyqxmd.com/read/28800648/fundus-autofluorescence-findings-in-eyes-with-birdshot-chorioretinitis
#2
Christian Böni, Jennifer E Thorne, Richard F Spaide, Trucian A Ostheimer, David Sarraf, Ralph D Levinson, Debra A Goldstein, Lana M Rifkin, Albert T Vitale, Glenn J Jaffe, Gary N Holland
Purpose: The purpose of this study was to describe fundus autofluorescence (FAF) findings in eyes with birdshot chorioretinitis (BSCR) and to compare findings to demographic, medical, and clinical characteristics. Methods: In this multicenter, prospective, cross-sectional study, 172 eyes (86 patients) with BSCR were investigated. Participants underwent a standardized evaluation including collection of demographic data, ophthalmic and treatment history, and ophthalmologic examination...
August 1, 2017: Investigative Ophthalmology & Visual Science
https://www.readbyqxmd.com/read/28800205/wide-field-color-imaging-of-scatter-based-tissue-contrast-using-both-high-spatial-frequency-illumination-and-cross-polarization-gating
#3
Mackenzie L Carlson, David M McClatchy, Jason R Gunn, Jonathan T Elliott, Keith D Paulsen, Stephen C Kanick, Brian W Pogue
This study characterizes the scatter-specific tissue contrast that can be obtained by high spatial frequency (HSF) domain imaging and cross-polarization (CP) imaging, using a standard color imaging system, and how combining them may be beneficial. Both HSF and CP approaches are known to modulate the sensitivity of epi-illumination reflectance images between diffuse multiply-scattered and superficially backscattered photons, providing enhanced contrast from microstructure and composition than what is achieved by standard wide-field imaging...
August 11, 2017: Journal of Biophotonics
https://www.readbyqxmd.com/read/28795358/psychophysical-measurements-of-luminance-contrast-sensitivity-and-color-discrimination-with-transparent-and-blue-light-filter-intraocular-lenses
#4
Marcelo Fernandes da Costa, Augusto Paranhos Júnior, Claudio Luiz Lottenberg, Leonardo Cunha Castro, Dora Fix Ventura
INTRODUCTION: The purpose of this study was to measure luminance contrast sensitivity and color vision thresholdfs in normal subjects using a blue light filter lens and transparent intraocular lens material. METHODS: Monocular luminance grating contrast sensitivity was measured with Psycho for Windows (version 2.36; Cambridge Research Systems) at 3.0, 6.0, 12.0, 20.0, and 30.0 cycles per degree of visual angle (cpd) in 15 normal subjects (eight female), with a mean age of 21...
August 9, 2017: Ophthalmology and Therapy
https://www.readbyqxmd.com/read/28762732/a-plasmonic-elisa-based-on-nanospherical-brush-induced-signal-amplification-for-the-ultrasensitive-naked-eye-simultaneous-detection-of-the-typical-tetrabromobisphenol-a-derivative-and-byproduct
#5
Zhen Zhang, Nuanfei Zhu, Shuaibing Dong, Menglu Huang, Liuqing Yang, Xiangyang Wu, Zhenjiang Liu, Jiahao Jiang, Yanmin Zou
Based on H2O2-mediated growth of gold nanoparticle (AuNPs), a novel plasmonic enzyme-linked immunosorbent assay (pELISA) was developed with a polyclonal antibody for the ultrasensitive simultaneous naked-eye detection of tetrabromobisphenol A bis(2-hydroxyetyl) ether (TBBPA DHEE) and tetrabromobisphenol A mono(hydroxyethyl) ether (TBBPA MHEE), one of the major derivatives and byproducts of tetrabromobisphenol A (TBBPA), respectively. In this modified indirect competitive pELISA, glucose oxidase (GOx) played an important role leading to the growth of AuNPs through a reaction between GOx and glucose to produce hydrogen peroxide (H2O2)...
August 1, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28762668/luminescent-properties-of-single-phase-ba2-x-1-5y-1-5z-p2-o7-xeu-2-yce-3-ztb-3-phosphors-for-white-light-emitting-diode
#6
Sha-Sha Liu, Da-Chuan Zhu, Cong Zhao, Tao Han
A series of Ba2 P2 O7 :xEu(2+) ,yCe(3+) ,zTb(3+) phosphors was synthesized via a co-precipitation method, then their crystal structure, quantum efficiency and luminescent properties were analyzed by XRD and FL, respectively. The results showed that these phosphors not only presented the excitation characteristics of Ba2 P2 O7 :xEu(2+) ,zTb(3+) , but also exhibited that of the Ba2 P2 O7 :yCe(3+) ,zTb(3+) phosphor. Meanwhile, the tri-doped phosphor showed a stronger absorption around 320 nm in contrast with the Eu(2+) /Ce(3+) :Tb(3+) co-doped phosphor...
August 1, 2017: Luminescence: the Journal of Biological and Chemical Luminescence
https://www.readbyqxmd.com/read/28751656/gene-based-therapy-in-a-mouse-model-of-blue-cone-monochromacy
#7
Yuxin Zhang, Wen-Tao Deng, Wei Du, Ping Zhu, Jie Li, Fan Xu, Jingfen Sun, Cecilia D Gerstner, Wolfgang Baehr, L Boye Sanford, Chen Zhao, William W Hauswirth, Ji-Jing Pang
Cones are responsible for daylight, central, high acuity and color vision. Three proteins found in human cones, i.e. long-wavelength (L)-, middle-wavelength (M)-, and short-wavelength sensitive (S)-opsins, are responsible for red, green and blue color recognition, respectively. Human blue cone monochromacy (BCM) is characterized by functional loss of both L- and M-cone opsins due to mutations in the OPN1LW/OPN1MW gene cluster on the X chromosome. BCM patients, who rely on their vision from only S-cones and rods, suffer severely reduced visual acuity and impaired color vision...
July 27, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28734946/impaired-rhodopsin-generation-in-the-rat-model-of-diabetic-retinopathy
#8
Volha V Malechka, Gennadiy Moiseyev, Yusuke Takahashi, Younghwa Shin, Jian-Xing Ma
Diabetic retinopathy is a common complication of diabetes mellitus. Diabetic patients experience functional deficits in dark adaptation, contrast sensitivity, and color perception before microvascular pathologies become apparent. Herein, we evaluated early changes in neural retinal function and in retinoid metabolism in the eye in diabetes. Streptozotocin-induced diabetic rats showed decreased a- and b-wave amplitudes of scotopic and photopic electroretinography responses 4 months after diabetes induction compared to nondiabetic controls...
July 19, 2017: American Journal of Pathology
https://www.readbyqxmd.com/read/28724749/columnar-segregation-of-magnocellular-and-parvocellular-streams-in-human-extrastriate-cortex
#9
Roger B H Tootell, Shahin Nasr
'Magno- vs. parvo-cellular' (M-P) streams are fundamental to the organization of macaque visual cortex. Segregated, paired M-P streams extend from retina through LGN into V1. The M stream extends further into area V5/MT, and parts of V2. However elsewhere in visual cortex, it remains unclear whether M-P-derived information 1) becomes intermixed, or 2) remains segregated in M-P dominated columns and neurons. Here we tested whether M-P streams exist in extrastriate cortical columns, in 8 human subjects (4 female)...
July 19, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28683118/reef-calcifiers-are-adapted-to-episodic-heat-stress-but-vulnerable-to-sustained-warming
#10
Marleen Stuhr, Claire E Reymond, Vera Rieder, Pamela Hallock, Jörg Rahnenführer, Hildegard Westphal, Michal Kucera
Shallow marine ecosystems naturally experience fluctuating physicochemical conditions across spatial and temporal scales. Widespread coral-bleaching events, induced by prolonged heat stress, highlight the importance of how the duration and frequency of thermal stress influence the adaptive physiology of photosymbiotic calcifiers. Large benthic foraminifera harboring algal endosymbionts are major tropical carbonate producers and bioindicators of ecosystem health. Like corals, they are sensitive to thermal stress and bleach at temperatures temporarily occurring in their natural habitat and projected to happen more frequently...
2017: PloS One
https://www.readbyqxmd.com/read/28669719/changing-similarity-stable-and-flexible-modulations-of-psychological-dimensions
#11
Michael Dieciuc, Nelson A Roque, Jonathan R Folstein
Successfully categorizing objects requires discriminating between relevant and irrelevant dimensions (e.g., shape, color). Categorization can lead to changes in the visual system that stretch psychological space, making relevant dimensions more distinct and irrelevant dimensions more similar. These changes are known as dimensional modulation (DM) and they can be both stable and flexible in nature. The current study examined the interaction between stable DM and flexible DM, as well as the time course of relative changes in similarity...
June 29, 2017: Brain Research
https://www.readbyqxmd.com/read/28656455/malignancy-detection-on-mammography-using-dual-deep-convolutional-neural-networks-and-genetically-discovered-false-color-input-enhancement
#12
Philip Teare, Michael Fishman, Oshra Benzaquen, Eyal Toledano, Eldad Elnekave
Breast cancer is the most prevalent malignancy in the US and the third highest cause of cancer-related mortality worldwide. Regular mammography screening has been attributed with doubling the rate of early cancer detection over the past three decades, yet estimates of mammographic accuracy in the hands of experienced radiologists remain suboptimal with sensitivity ranging from 62 to 87% and specificity from 75 to 91%. Advances in machine learning (ML) in recent years have demonstrated capabilities of image analysis which often surpass those of human observers...
August 2017: Journal of Digital Imaging: the Official Journal of the Society for Computer Applications in Radiology
https://www.readbyqxmd.com/read/28653828/generating-color-from-polydisperse-near-micron-sized-tio2-particles
#13
Al-Mahmnur Alam, Kyungnae Baek, Jieun Son, Yi-Rong Pei, Dong Ha Kim, Jin-Ho Choy, Jerome K Hyun
Single particle Mie calculations of near micron-sized TiO2 particles predict strong light scattering dominating the visible range that would give rise to a white appearance. We demonstrate that a polydisperse collection of these "white" particles can result in the generation of visible colors through ensemble scattering. The weighted averaging of the scattering over the particle size distribution modifies the sharp, multiple, high order scattering modes from individual particles into broad variations in the collective extinction...
July 19, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28647197/characterizing-tissue-perfusion-after-lower-extremity-intervention-using-two-dimensional-color-coded-digital-subtraction-angiography
#14
Ann H Kim, Andrew J Shevitz, Katherine L Morrow, Daniel E Kendrick, Karem Harth, Henry Baele, Vikram S Kashyap
OBJECTIVE: Digital subtraction angiography (DSA) of the peripheral arterial vasculature provides lumenographic information but only a qualitative assessment of blood flow. The ability to quantify adequate tissue perfusion of the lower extremities would enable real-time perfusion assessment during DSA of patients with peripheral arterial disease (PAD). In this study, we used a novel real-time imaging software to delineate tissue perfusion parameters in the foot in PAD patients. METHODS: Between March 2015 and June 2016, patients (N = 31) underwent lower extremity angiography using a two-dimensional perfusion (2DP) imaging protocol (Philips Healthcare, Andover, Mass)...
June 21, 2017: Journal of Vascular Surgery
https://www.readbyqxmd.com/read/28633153/association-between-visual-function-and-subretinal-drusenoid-deposits-in-normal-and-early-age-related-macular-degeneration-eyes
#15
David Neely, Anna V Zarubina, Mark E Clark, Carrie E Huisingh, Gregory R Jackson, Yuhua Zhang, Gerald McGwin, Christine A Curcio, Cynthia Owsley
PURPOSE: To examine the association between subretinal drusenoid deposits (SDDs) identified by multimodal retinal imaging and visual function in older eyes with normal macular health or in the earliest phases of age-related macular degeneration (AMD). METHODS: Age-related macular degeneration status for each eye was defined according to the Age-Related Eye Disease Study (AREDS) 9-step classification system (normal = Step 1, early AMD = Steps 2-4) based on color fundus photographs...
July 2017: Retina
https://www.readbyqxmd.com/read/28628420/value-of-multiparametric-us-in-the-assessment-of-intratesticular-lesions
#16
Thomas Auer, Tobias De Zordo, Christian Dejaco, Leonhard Gruber, Renate Pichler, Werner Jaschke, Vikram S Dogra, Friedrich Aigner
Purpose To evaluate the diagnostic accuracy of multiparametric ultrasonography (US) consisting of gray-scale US, color Doppler US, strain elastography, and contrast agent-enhanced US in the assessment of intratesticular lesions. Materials and Methods Institutional review board approval was obtained for this retrospective study. From January 2012 to December 2015, 55 focal testicular lesions that were indeterminate on gray-scale US scans were further characterized with color Doppler US, strain elastography, and contrast-enhanced US...
June 16, 2017: Radiology
https://www.readbyqxmd.com/read/28600993/robust-sensitive-and-facile-method-for-detection-of-f-cn-and-ac-anions
#17
P Madhusudhana Reddy, Shih-Rong Hsieh, Jem-Kun Chen, Chi-Jung Chang, Jing-Yuan Kang, Chih-Hsien Chen
Sensing of F(-), CN(-) and Ac(-) is important from the viewpoint of both medically and environmentally. Particularly, sensing of the anions in 100% water by a colorimetric chemical sensor is a highly difficult task as water molecules interfere the sensing mechanism. In this regard, sensor R1, having azo and nitrophenyl groups as signaling units and thiourea as a binding site was prepared. This sensor exclusively detected CN(-) ion over other testing anions in 30% aq. DMSO solution by exhibiting distinct spectral and visual color changes...
June 6, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28597330/the-utility-of-superb-microvascular-imaging-for-monitoring-low-velocity-venous-flow-following-pancreas-transplantation-report-of-a-case
#18
Kazuaki Tokodai, Shigehito Miyagi, Chikashi Nakanishi, Yasuyuki Hara, Wataru Nakanishi, Koji Miyazawa, Kenji Shimizu, Masafumi Goto, Takashi Kamei, Michiaki Unno
Vascular thrombosis is a major complication after pancreas transplantation. Because delays in detecting thrombosis often result in graft failure, monitoring blood flow is crucial. Periodic evaluation using color Doppler ultrasonography is mostly performed for monitoring blood flow in the grafted pancreas. However, conventional color Doppler imaging has limited capability to visualize low-velocity blood flow. Superb microvascular imaging (SMI) is a novel ultrasound Doppler technique that is especially sensitive in detecting low-velocity flow...
June 8, 2017: Journal of Medical Ultrasonics
https://www.readbyqxmd.com/read/28574037/-diagnostic-significance-of-the-color-duplex-scanning-in-estimation-of-the-arteries-state-at-different-stages-of-infrainguinal-reconstructions
#19
I E Timina, I I Piatkova, A E Zotikov, Z A Adyrkhaev
AIM: The study was aimed at assessing diagnostic possibilities of duplex scanning (DS) of lower limb arteries, used as 'ultrasonographic angiography' in patients presenting with critical ischaemia for appropriately planning complicated infrainguinal reconstructions at stages of surgical management, including dynamic follow up in the postoperative period. PATIENTS AND METHODS: We examined a total of 30 patients. Of these, 14 patients composed the control group and 16 patients with critical ischaemia of lower limb arteries who underwent 8 external iliac-tibial and 8 femorotibial bypass graftings with a relieving arteriovenous fistula and application of a venous cuff according to the type of 'St...
2017: Angiologii︠a︡ i Sosudistai︠a︡ Khirurgii︠a︡, Angiology and Vascular Surgery
https://www.readbyqxmd.com/read/28567705/diagnostic-value-of-doppler-echocardiography-for-identifying-hemodynamic-significant-pulmonary-valve-regurgitation-in-tetralogy-of-fallot-comparison-with-cardiac-mri
#20
Niek E G Beurskens, Thomas M Gorter, Petronella G Pieper, Elke S Hoendermis, Beatrijs Bartelds, Tjark Ebels, Rolf M F Berger, Tineke P Willems, Joost P van Melle
Quantification of pulmonary regurgitation (PR) is essential in the management of patients with repaired tetralogy of Fallot (TOF). We sought to evaluate the accuracy of first-line Doppler echocardiography in comparison with cardiac magnetic resonance imaging (MRI) to identify hemodynamic significant PR. Paired cardiac MRI and echocardiographic studies (n = 97) in patients with repaired TOF were retrospectively analyzed. Pressure half time (PHT) and pulmonary regurgitation index (PRi) were measured using continuous wave Doppler...
May 31, 2017: International Journal of Cardiovascular Imaging
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