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1.
J Reconstr Microsurg ; 38(5): 420-428, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34470059

RESUMO

BACKGROUND: An objective, non-invasive method for redness detection during acute allograft rejection in face transplantation (FT) is lacking. METHODS: A retrospective cohort study was performed with 688 images of 7 patients with face transplant (range, 1 to 108 months post-transplant). Healthy controls were matched to donor age, sex, and had no prior facial procedures. Rejection state was confirmed via tissue biopsy. An image-analysis software developed alongside VicarVision (Amsterdam, Netherlands) was used to produce R, a measure of differences between detectable color and absolute red. R is inversely proportional to redness, where lower R values correspond to increased redness. Linear mixed models were used to study fixed effect of rejection state on R values. Estimated marginal means of fitted models were calculated for pairwise comparisons. RESULTS: Of 688 images, 175, 170, 202, and 141 images were attributable to Banff Grade 0,1,2, and 3, respectively. Estimated change in R value of facial allografts decreased with increasing Banff Grade (p = 0.0001). The mean R value of clinical rejection (Banff Grade ⅔) (16.67, 95% Confidence Interval [CI] 14.79-18.58) was lower (p = 0.005) than non-rejection (Banff Grade 0/1) (19.38, 95%CI 17.43-21.33). Both clinical and non-rejection mean R values were lower (p = 0.0001) than healthy controls (24.12, 95%CI 20.96-27.28). CONCLUSION: This proof-of-concept study demonstrates that software-based analysis can detect and monitor acute rejection changes in FT. Future studies should expand on this tool's potential application in telehealth and as a screening tool for allograft rejection.


Assuntos
Transplante de Face , Transplante de Rim , Aloenxertos , Biópsia , Rejeição de Enxerto , Humanos , Estudos Retrospectivos , Software
2.
Sensors (Basel) ; 23(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36616937

RESUMO

Markerless estimation of 3D Kinematics has the great potential to clinically diagnose and monitor movement disorders without referrals to expensive motion capture labs; however, current approaches are limited by performing multiple de-coupled steps to estimate the kinematics of a person from videos. Most current techniques work in a multi-step approach by first detecting the pose of the body and then fitting a musculoskeletal model to the data for accurate kinematic estimation. Errors in training data of the pose detection algorithms, model scaling, as well the requirement of multiple cameras limit the use of these techniques in a clinical setting. Our goal is to pave the way toward fast, easily applicable and accurate 3D kinematic estimation. To this end, we propose a novel approach for direct 3D human kinematic estimation D3KE from videos using deep neural networks. Our experiments demonstrate that the proposed end-to-end training is robust and outperforms 2D and 3D markerless motion capture based kinematic estimation pipelines in terms of joint angles error by a large margin (35% from 5.44 to 3.54 degrees). We show that D3KE is superior to the multi-step approach and can run at video framerate speeds. This technology shows the potential for clinical analysis from mobile devices in the future.


Assuntos
Algoritmos , Redes Neurais de Computação , Humanos , Fenômenos Biomecânicos , Captura de Movimento
3.
Planta Med ; 85(14-15): 1160-1167, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31408886

RESUMO

The medicinal plant Actaea racemosa is a perennial, whose rhizome (black cohosh rhizome) is usually wild harvested on a multiton scale to meet market requirements. Since this North American species is increasingly endangered, cultivation is needed. Even though studies prove that cultivation is possible, it has not been widely established. This may be due to a different quality of cultivated material, which does not comply with current pharmacopoeial requirements. This study compares contents and chromatographic fingerprints of phenolic acids and triterpene glycosides in different types of black cohosh rhizomes. Commercial batches from wild harvests were compared to individual plants from the wild and from cultivation. Phenolic acids' contents and profiles were generally comparable between wild harvesting and cultivation. On the contrary, the total triterpene glycoside content was significantly lower in cultivation (p ≤ 0.001). In individual plants, different profiles of triterpene glycosides occurred. Possibly, specimen or chemotype selection for cultivation would cause a shift of the triterpene glycoside profile of cultivation batches away from the common pattern found in batches from wild harvesting. Potentially, such differences have an impact on the efficacy of black cohosh herbal products, if cultivated plant material is used for manufacturing.


Assuntos
Cimicifuga/química , Glicosídeos/química , Hidroxibenzoatos/química , Triterpenos/química , Cromatografia Líquida , Espectrometria de Massas , Plantas Medicinais , Rizoma/química
4.
PLoS One ; 13(3): e0194737, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29584738

RESUMO

In face-to-face social interactions, blind and visually impaired persons (VIPs) lack access to nonverbal cues like facial expressions, body posture, and gestures, which may lead to impaired interpersonal communication. In this study, a wearable sensory substitution device (SSD) consisting of a head mounted camera and a haptic belt was evaluated to determine whether vibrotactile cues around the waist could be used to convey facial expressions to users and whether such a device is desired by VIPs for use in daily living situations. Ten VIPs (mean age: 38.8, SD: 14.4) and 10 sighted persons (SPs) (mean age: 44.5, SD: 19.6) participated in the study, in which validated sets of pictures, silent videos, and videos with audio of facial expressions were presented to the participant. A control measurement was first performed to determine how accurately participants could identify facial expressions while relying on their functional senses. After a short training, participants were asked to determine facial expressions while wearing the emotion feedback system. VIPs using the device showed significant improvements in their ability to determine which facial expressions were shown. A significant increase in accuracy of 44.4% was found across all types of stimuli when comparing the scores of the control (mean±SEM: 35.0±2.5%) and supported (mean±SEM: 79.4±2.1%) phases. The greatest improvements achieved with the support of the SSD were found for silent stimuli (68.3% for pictures and 50.8% for silent videos). SPs also showed consistent, though not statistically significant, improvements while supported. Overall, our study shows that vibrotactile cues are well suited to convey facial expressions to VIPs in real-time. Participants became skilled with the device after a short training session. Further testing and development of the SSD is required to improve its accuracy and aesthetics for potential daily use.


Assuntos
Cegueira/psicologia , Expressão Facial , Pessoas com Deficiência Visual/psicologia , Dispositivos Eletrônicos Vestíveis , Estimulação Acústica , Adolescente , Adulto , Cegueira/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa , Análise e Desempenho de Tarefas , Adulto Jovem
5.
Front Neurol ; 8: 279, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28659862

RESUMO

External cueing is a potentially effective strategy to reduce freezing of gait (FOG) in persons with Parkinson's disease (PD). Case reports suggest that three-dimensional (3D) cues might be more effective in reducing FOG than two-dimensional cues. We investigate the usability of 3D augmented reality visual cues delivered by smart glasses in comparison to conventional 3D transverse bars on the floor and auditory cueing via a metronome in reducing FOG and improving gait parameters. In laboratory experiments, 25 persons with PD and FOG performed walking tasks while wearing custom-made smart glasses under five conditions, at the end-of-dose. For two conditions, augmented visual cues (bars/staircase) were displayed via the smart glasses. The control conditions involved conventional 3D transverse bars on the floor, auditory cueing via a metronome, and no cueing. The number of FOG episodes and percentage of time spent on FOG were rated from video recordings. The stride length and its variability, cycle time and its variability, cadence, and speed were calculated from motion data collected with a motion capture suit equipped with 17 inertial measurement units. A total of 300 FOG episodes occurred in 19 out of 25 participants. There were no statistically significant differences in number of FOG episodes and percentage of time spent on FOG across the five conditions. The conventional bars increased stride length, cycle time, and stride length variability, while decreasing cadence and speed. No effects for the other conditions were found. Participants preferred the metronome most, and the augmented staircase least. They suggested to improve the comfort, esthetics, usability, field of view, and stability of the smart glasses on the head and to reduce their weight and size. In their current form, augmented visual cues delivered by smart glasses are not beneficial for persons with PD and FOG. This could be attributable to distraction, blockage of visual feedback, insufficient familiarization with the smart glasses, or display of the visual cues in the central rather than peripheral visual field. Future smart glasses are required to be more lightweight, comfortable, and user friendly to avoid distraction and blockage of sensory feedback, thus increasing usability.

6.
Planta Med ; 83(12-13): 1085-1096, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28403500

RESUMO

Rhizomes of Actaea racemosa L. (formerly Cimicifuga racemosa) gained increasing interest as a plant-derived drug due to its hormone-like activity and the absence of estrogenic activity. According to the Current Good Manufacturing Practices guidelines and pharmacopeial standards, quality assessment of herbal starting materials includes tests on identity and substitution, as well as quantification of secondary metabolites, usually by HPTLC and LC methods. To reduce the laboratory effort, we investigated near-infrared spectroscopy for rapid species authentication and quantification of metabolites of interest.Near-infrared spectroscopy analysis is carried out directly on the milled raw plant material. Spectra were correlated with reference data of polyphenols and triterpene glycosides determined by LC/diode array detection and LC/evaporative light scattering detection, respectively. Quantification models were built and validated by cross-validation procedures. Clone plants, derived by vegetative propagation, and plants of a collection from different geographical origins cultivated in Berlin were analysed together with mixed batches from wild harvests purchased at wholesalers.Generally, good to excellent correlations were found for the overall content of polyphenols with coefficients of determination of R2 > 0.93. For individual polyphenols such as fukinolic acid, only models containing clone plants succeeded (R2 > 0.92). For the total content of triterpene glycosides, results were generally worse in comparison to polyphenols and were observed only for the mixed batches (R2 = 0.93).Next to quantitative analysis, near-infrared spectroscopy was proven as a rapid alternative to other, more laborious methods for species authentication. Near-infrared spectroscopy was able to distinguish different Actaea spp. such as the North American Actaea cordifolia and the Asian Actaea cimicifuga, Actaea dahurica, Actaea heracleifolia, and Actaea simplex.


Assuntos
Cimicifuga/química , Glicosídeos/análise , Polifenóis/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Triterpenos/análise , Ácidos Cafeicos/análise , Ácidos Cafeicos/química , Cromatografia Líquida , Glicosídeos/química , Fenilacetatos/análise , Fenilacetatos/química , Plantas Medicinais , Polifenóis/química , Controle de Qualidade , Rizoma/química , Triterpenos/química
7.
Phytochem Anal ; 27(6): 318-325, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27690371

RESUMO

INTRODUCTION: The medicinal plant Actaea racemosa L. (Ranunculaceae, aka black cohosh) is widely used to treat climacteric complaints as an alternative to hormone substitution. Recent trials prove efficacy and safety of the approved herbal medicinal products from extracts of pharmaceutical quality. This led to worldwide increasing sales. A higher demand for the plant material results in problems with economically motivated adulteration. Thus, reliable tools for herbal drug authentication are necessary. OBJECTIVE: To develop an economical, plain, and rapid method to distinguish between closely related American and Asian Actaea species, using securely established and resilient analytical methods coupled to a chemometric evaluation of the resulting data. METHODOLOGY: We developed and validated a RP-PDA-HPLC method including an extraction by ultra-sonication to determine the genuine contents of partly hydrolysis-sensitive polyphenols in Actaea racemosa roots and rhizomes, and applied it to a large number of 203 Actaea samples consisting of seven species. RESULTS: We were able to generate reliable data with regards to the polyphenolic esters in the samples. The evaluation of this data by principle component analysis (PCA) made a discrimination between Asian Actaea species (sheng ma), one American Actaea species (Appalachian bugbane), and A. racemosa possible. CONCLUSION: The developed RP-PDA-HPLC method coupled to PCA is an excellent tool for authentication of the Actaea racemosa herbal drug, and can be a powerful addition to the TLC methods used in the dedicated pharmacopoeias, and is a promising alternative to expensive and lots of expertise requiring methods. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Cimicifuga/química , Custos e Análise de Custo , Medicina Herbária , Análise de Componente Principal
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