To determine whether dynamic visual acuity (DVA) during head rotations on the stationary body can lateralize unilateral vestibular deafferentation and detect non-labyrinthine compensation mechanisms, 15 normal and 11 subjects with unilateral vestibular deafferentation underwent manually imposed and self-generated transient yaw head rotations during measurement of binocular DVA. DVA was measured by a four-alternative, forced choice, staircase procedure with optotype presentation only when head velocity exceeded thresholds of 50 degree or 75 degree/s. Eye and head movements were recorded using search coils to characterize ocular motor strategies. During directionally unpredictable, manually imposed contralesional rotation, unilaterally deafferented subjects had decreases in DVA from the static condition of 0.36 +/- 0.22 and 0.47 +/- 0.53 log of the minimum angle resolvable (logMAR, mean +/- SD), respectively, for 50 degree and 75 degree/s thresholds, not significantly greater than those of normal subjects (0.26 +/- 0.13 and 0.36 +/- 0.14, P>0.05). However, during manually imposed ipsilesional rotation, vestibulopathic subjects had decreases in DVA of 0.66 +/- 0.36 and 1.08 +/- 0.47 logMAR, significantly greater than during contralesional rotation ( P<0.01). The DVA reduction difference for the ipsi- and contralesional directions was less during self-generated than during manually imposed head rotations. The directional difference for manually administered head rotations yielded a robust diagnostic measure with essentially no overlap in performance with normal subjects. Diagnostic performance for DVA during self-generated head rotation was poorer. Recordings of eye and head movements made using search coils during DVA testing confirmed a deficient vestibulo-ocular reflex (VOR) during ipsilesional rotation, with most unilaterally vestibulopathic subjects employing predictive smooth eye movements and vestibular catch-up saccades. Measurement of DVA during transient head rotation on the body thus reliably can detect and lateralize vestibular pathology and compensatory mechanisms. Extravestibular mechanisms for compensation appear more effective during self-generated than manually imposed head rotations.
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http://dx.doi.org/10.1007/s00221-001-0959-7 | DOI Listing |
Complement Ther Med
December 2024
Division of Digestive Diseases, Department of Korean Internal Medicine, Kyung Hee University Korean Medicine Hospital, 23 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Republic of Korea; Department of Digestive Diseases, College of Korean Medicine, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Republic of Korea; Department of Clinical Korean Medicine, Graduate School, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Republic of Korea. Electronic address:
Background: Functional dyspepsia (FD) is the most prevalent pediatric gastrointestinal disorder, imposing a significant burden on healthcare services and often persisting into adulthood. Tuina, a traditional manual therapy, is frequently employed in the treatment of FD. This study aimed to systematically evaluate the efficacy and safety of Tuina in treating FD in children.
View Article and Find Full Text PDFActa Psychol (Amst)
November 2024
Department of Psychology, University of California, Riverside, Riverside, CA 92521, United States of America. Electronic address:
Proteins
December 2024
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warszawa, Poland.
α/β Hydrolase-like enzymes form a large and functionally diverse superfamily of proteins. Despite retaining a conserved structural core consisting of an eight-stranded, central β-sheet flanked with six α-helices, they display a modular architecture allowing them to perform a variety of functions, like esterases, lipases, peptidases, epoxidases, lyases, and others. At the same time, many α/β hydrolase-like families, even enzymatically distinct, share a high degree of sequence similarity.
View Article and Find Full Text PDFTarget Oncol
November 2024
IT-Infrastructure for Translational Medical Research, University of Augsburg, Augsburg, Germany.
Transl Vis Sci Technol
November 2024
Clinical Trials Branch, Division of Epidemiology and Clinical Applications, National Eye Institute, National Institutes of Health, Bethesda, MD, USA.
Purpose: This study aimed to develop an algorithm for automated detection of drusenoid pigment epithelial detachments (DPEDs) in optical coherence tomography (OCT) volumes of patients with age-related macular degeneration (AMD) and to compare its performance against traditional reading center grading on color-fundus photographs (CFPs).
Methods: Eyes with a range of AMD severities, excluding neovascular disease, were imaged using spectral-domain OCT (SD-OCT) and paired CFPs and were followed annually for up to 5 years. DPEDs were automatically identified by segmenting the retinal pigment epithelium (RPE) and Bruch's membrane (BM) layers from the SD-OCT volumes and imposing both a minimum RPE BM height (>75 µm) and a two-dimensional length requirement (>433 µm).
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