108 research outputs found

    Automated video-based assessment of facial bradykinesia in de-novo Parkinson's disease.

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    Even though hypomimia is a hallmark of Parkinson's disease (PD), objective and easily interpretable tools to capture the disruption of spontaneous and deliberate facial movements are lacking. This study aimed to develop a fully automatic video-based hypomimia assessment tool and estimate the prevalence and characteristics of hypomimia in de-novo PD patients with relation to clinical and dopamine transporter imaging markers. For this cross-sectional study, video samples of spontaneous speech were collected from 91 de-novo, drug-naïve PD participants and 75 age and sex-matched healthy controls. Twelve facial markers covering areas of forehead, nose root, eyebrows, eyes, lateral canthal areas, cheeks, mouth, and jaw were used to quantitatively describe facial dynamics. All patients were evaluated using Movement Disorder Society-Unified PD Rating Scale and Dopamine Transporter Single-Photon Emission Computed Tomography. Newly developed automated facial analysis tool enabled high-accuracy discrimination between PD and controls with area under the curve of 0.87. The prevalence of hypomimia in de-novo PD cohort was 57%, mainly associated with dysfunction of mouth and jaw movements, and decreased variability in forehead and nose root wrinkles (p < 0.001). Strongest correlation was found between reduction of lower lip movements and nigro-putaminal dopaminergic loss (r = 0.32, p = 0.002) as well as limb bradykinesia/rigidity scores (r = -0.37 p < 0.001). Hypomimia represents a frequent, early marker of motor impairment in PD that can be robustly assessed via automatic video-based analysis. Our results support an association between striatal dopaminergic deficit and hypomimia in PD

    Articulatory undershoot of vowels in isolated REM sleep behavior disorder and early Parkinson's disease.

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    Imprecise vowels represent a common deficit associated with hypokinetic dysarthria resulting from a reduced articulatory range of motion in Parkinson's disease (PD). It is not yet unknown whether the vowel articulation impairment is already evident in the prodromal stages of synucleinopathy. We aimed to assess whether vowel articulation abnormalities are present in isolated rapid eye movement sleep behaviour disorder (iRBD) and early-stage PD. A total of 180 male participants, including 60 iRBD, 60 de-novo PD and 60 age-matched healthy controls performed reading of a standardized passage. The first and second formant frequencies of the corner vowels /a/, /i/, and /u/ extracted from predefined words, were utilized to construct articulatory-acoustic measures of Vowel Space Area (VSA) and Vowel Articulation Index (VAI). Compared to controls, VSA was smaller in both iRBD (p = 0.01) and PD (p = 0.001) while VAI was lower only in PD (p = 0.002). iRBD subgroup with abnormal olfactory function had smaller VSA compared to iRBD subgroup with preserved olfactory function (p = 0.02). In PD patients, the extent of bradykinesia and rigidity correlated with VSA (r = -0.33, p = 0.01), while no correlation between axial gait symptoms or tremor and vowel articulation was detected. Vowel articulation impairment represents an early prodromal symptom in the disease process of synucleinopathy. Acoustic assessment of vowel articulation may provide a surrogate marker of synucleinopathy in scenarios where a single robust feature to monitor the dysarthria progression is needed

    Sodium carbonate revisited

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    Crystal structure of NaCd(H2PO3)3·H2O and spectroscopic study of NaM(H2PO3)3·H2O, M= Mn, Co, Ni, Zn, Mg and Cd

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    NaCd(H2PO3)3·H2O was synthesized in solution and its structure was studied by single-crystal X-ray diffraction. It crystallizes in the orthorhombic system (Pbca, Z = 8) with the cell parameters: a = 9.2895(14) Å, b = 15.124(2) Å, c = 15.0592(12) Å. Final residual factors R/Rw are 0.0297/0.0790. Both Na+ and Cd2+ are octahedrally coordinated, [NaO6] and [CdO6] share edges to form zigzag chains along [1 0 0]. The 3D framework is build upon these chains which are interconnected by H2PO3 pseudo-pyramids and an intricate network of weak hydrogen bonds. NaCd(H2PO3)3·H2O belongs the series of isostructural phosphites NaM(H2PO3)3·H2O (M = Mn, Co, Ni, Zn and Mg). IR spectroscopic studies show the bands confirming the presence of the phosphite H2PO32− anion in the whole series NaM(H2PO3)3·H2O, M = Mn, Co, Ni, Zn, Mg and Cd. The UV–Vis spectroscopy was used for characterizing the d–d transitions in the Mn, Co and Ni phosphites.The financial support from Centre National de Recherche Scientifique et Technique (CNRST) (Morocco) (URAC 19). The institutional research plan No. AVOZ10100521 of the Institute of Physics and the grant “Praemium Academiae” of the Academy of Sciences of the Czech Republic

    Sodium carbonate revisited

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