The aim of this work was to develop and validate an ultraviolet derivative spectrophotometric (UVDS) method for the quantitative determination of allantoin (ALL) in liposomes, gels and creams. Liposomes were prepared by methods of thin film hydration and mechanical agitation. Solutions of ALL in 0.1 mol/L NaOH with ethanol:water (70:30, v/v) were prepared in order to destroy liposome vesicles. Spectral interference from components of liposomes, cream, gel and ALL degradation products was eliminated using the second-order derivative of the zero-order spectrum. Characterization of ALL in 0.1 mol/L NaOH was carried out by direct infusion mass spectrometry. Absorbances of ALL solutions were measured at 266.6 nm of the second-derivative spectrum and linearity was observed in the ALL concentration range of 50-300 μgmL(-1) (correlation coefficient (r)=0.9961). The mean recovery percentage was 100.68 ± 1.61, repeatability expressed as relative standard deviation (RSD) was 1.07 and 2.12%, and intermediate precision (RSD) was 2.16%. The proposed UVDS method was found to be linear, precise, accurate, robust and selective, providing rapid and specific determination of ALL in raw materials and in topical formulations.
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http://dx.doi.org/10.1016/j.saa.2012.02.022 | DOI Listing |
Otolaryngol Head Neck Surg
December 2024
School of Audiology and Speech Sciences, University of British Columbia, Vancouver, Canada.
Objective: Balance deficits are common and debilitating. Standard treatments have limitations in addressing symptoms and restoring dynamic balance function. This study compares a rehabilitative computerized dynamic posturography (CDP) protocol, computerized vestibular retraining therapy (CVRT), with a home exercise program (HEP) for patients with objectively confirmed unilateral vestibular deficits (UVDs).
View Article and Find Full Text PDFIEEE Trans Pattern Anal Mach Intell
October 2018
Sufficient training examples are the fundamental requirement for most of the learning tasks. However, collecting well-labelled training examples is costly. Inspired by Zero-shot Learning (ZSL) that can make use of visual attributes or natural language semantics as an intermediate level clue to associate low-level features with high-level classes, in a novel extension of this idea, we aim to synthesise training data for novel classes using only semantic attributes.
View Article and Find Full Text PDFJ Neurosci Methods
January 2018
Aix Marseille Université, CNRS, UMR 7260, Laboratoire de Neurosciences Intégratives et Adaptatives - Equipe physiopathologie et Thérapie des Désordres Vestibulaires, Marseille, France. Electronic address:
Background: Unilateral vestibular deafferentation syndrome (uVDS) holds a particular place in the vestibular pathology domain. Due to its suddenness, the violence of its symptoms that often result in emergency hospitalization, and its associated original neurophysiological properties, this syndrome is a major source of questioning for the otoneurology community. Also, its putative pathogenic causes remain to be determined.
View Article and Find Full Text PDFPLoS One
October 2014
Central Clinical School, University of Sydney, Sydney, Australia ; Institute of Clinical Neuroscience, Royal Prince Alfred Hospital, Sydney, Australia.
Background: Vestibular reflexes, evoked by human electrical (galvanic) vestibular stimulation (EVS), are utilized to assess vestibular function and investigate its pathways. Our study aimed to investigate the electrically-evoked vestibulo-ocular reflex (eVOR) output after bilateral and unilateral vestibular deafferentations to determine the characteristics for interpreting unilateral lesions such as vestibular schwannomas.
Methods: EVOR was recorded with dual-search coils as binocular three-dimensional eye movements evoked by bipolar 100 ms-step at EVS intensities of [0.
Spectrochim Acta A Mol Biomol Spectrosc
June 2012
Departamento de Medicamentos, Faculdade de Farmácia, UFRJ, Rio de Janeiro, Brazil.
The aim of this work was to develop and validate an ultraviolet derivative spectrophotometric (UVDS) method for the quantitative determination of allantoin (ALL) in liposomes, gels and creams. Liposomes were prepared by methods of thin film hydration and mechanical agitation. Solutions of ALL in 0.
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