Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 60
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Sensors (Basel) ; 24(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38894287

RESUMO

Upper-limb paralysis requires extensive rehabilitation to recover functionality for everyday living, and such assistance can be supported with robot technology. Against such a background, we have proposed an electromyography (EMG)-driven hybrid rehabilitation system based on motion estimation using a probabilistic neural network. The system controls a robot and functional electrical stimulation (FES) from movement estimation using EMG signals based on the user's intention, enabling intuitive learning of joint motion and muscle contraction capacity even for multiple motions. In this study, hybrid and visual-feedback training were conducted with pointing movements involving the non-dominant wrist, and the motor learning effect was examined via quantitative evaluation of accuracy, stability, and smoothness. The results show that hybrid instruction was as effective as visual feedback training in all aspects. Accordingly, passive hybrid instruction using the proposed system can be considered effective in promoting motor learning and rehabilitation for paralysis with inability to perform voluntary movements.


Assuntos
Eletromiografia , Aprendizagem , Robótica , Humanos , Eletromiografia/métodos , Aprendizagem/fisiologia , Robótica/métodos , Masculino , Movimento/fisiologia , Redes Neurais de Computação , Adulto , Feminino , Movimento (Física)
2.
Sci Technol Adv Mater ; 22(1): 272-279, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33907526

RESUMO

The large anisotropic thermal conduction of a carbon nanotube (CNT) sheet that originates from the in-plane orientation of one-dimensional CNTs is disadvantageous for thermoelectric conversion using the Seebeck effect since the temperature gradient is difficult to maintain in the current flow direction. To control the orientation of the CNTs, polymer particles are introduced as orientation aligners upon sheet formation by vacuum filtration. The thermal conductivities in the in-plane direction decrease as the number of polymer particles in the sheet increases, while that in the through-plane direction increases. Consequently, a greater temperature gradient is observed for the anisotropy-controlled CNT sheet as compared to that detected for the CNT sheet without anisotropy control when a part of the sheet is heated, which results in a higher power density for the planar-type thermoelectric device. These findings are quite useful for the development of flexible and wearable thermoelectric batteries using CNT sheets.

3.
J Proteome Res ; 19(9): 3779-3791, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32538093

RESUMO

Prefractionation of complex mixtures of proteins derived from biological samples is indispensable for proteome analysis via top-down mass spectrometry (MS). Polyacrylamide gel electrophoresis (PAGE), which enables high-resolution protein separation based on molecular size, is a widely used technique in biochemical experiments and has the potential to be useful in sample fractionation for top-down MS analysis. However, the lack of a means to efficiently recover the separated proteins in-gel has always been a barrier to its use in sample prefractionation. In this study, we present a novel experimental workflow, called Passively Eluting Proteins from Polyacrylamide gels as Intact species for MS ("PEPPI-MS"), which allows top-down MS of PAGE-separated proteins. The optimization of Coomassie brilliant blue staining followed by the passive extraction step in the PEPPI-MS workflow enabled the efficient recovery of proteins, separated on commercial precast gels, from a wide range of molecular weight regions in under 10 min. Two-dimensional separation combining offline PEPPI-MS with online reversed-phase liquid chromatographic separation resulted in identification of over 1000 proteoforms recovered from the target region of the gel (≤50 kDa). Given the widespread availability and relatively low cost of traditional sodium dodecyl sulfate (SDS)-PAGE equipment, the PEPPI-MS workflow will be a powerful prefractionation strategy for top-down proteomics.


Assuntos
Resinas Acrílicas , Eletroforese em Gel de Poliacrilamida , Espectrometria de Massas
4.
Appl Microbiol Biotechnol ; 101(23-24): 8557-8569, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29032472

RESUMO

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS)-based microbial identification is a popular analytical method. Strain Solution proteotyping software available for MALDI-TOF MS has great potential for the precise and detailed discrimination of microorganisms at serotype- or strain-level, beyond the conventional mass fingerprinting approaches. Here, we constructed a theoretically calculated mass database of Salmonella enterica subspecies enterica consisting of 12 biomarker proteins: ribosomal proteins S8, L15, L17, L21, L25, and S7, Mn-cofactor-containing superoxide dismutase (SodA), peptidyl-prolyl cis-trans isomerase C (PPIase C), and protein Gns, and uncharacterized proteins YibT, YaiA, and YciF, that can allow serotyping of Salmonella. Strain Solution ver. 2 software with the novel database constructed in this study demonstrated that 109 strains (94%), including the major outbreak-associated serotypes, Enteritidis, Typhimurium, and Infantis, could be correctly identified from others by colony-directed MALDI-TOF MS using 116 strains belonging to 23 kinds of typed and untyped serotypes of S. enterica from culture collections, patients, and foods. We conclude that Strain Solution ver. 2 software integrated with the accurate mass database will be useful for the bacterial proteotyping by MALDI-TOF MS-based microbial classification in the clinical and food safety fields.


Assuntos
Proteínas de Bactérias/análise , Proteínas de Bactérias/química , Biologia Computacional/métodos , Salmonella enterica/química , Salmonella enterica/classificação , Sorotipagem/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Microbiologia de Alimentos , Humanos , Infecções por Salmonella/microbiologia , Salmonella enterica/isolamento & purificação , Software
5.
J Org Chem ; 81(17): 7373-83, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27400027

RESUMO

The targets of antifungal antibiotics in clinical use are more limited than those of antibacterial antibiotics. Therefore, new antifungal antibiotics with different mechanisms of action are desired. In the course of our screening for antifungal antibiotics of microbial origins, new antifungal antibiotics, simplifungin (1) and valsafungins A (2) and B (3), were isolated from cultures of the fungal strains Simplicillium minatense FKI-4981 and Valsaceae sp. FKH-53, respectively. The structures of 1 to 3 including their absolute stereochemistries were elucidated using various spectral analyses including NMR and collision-induced dissociation (CID)-MS/MS as well as chemical approaches including modifications to the Mosher's method. They were structurally related to myriocin. They inhibited the growth of yeast-like and zygomycetous fungi with MICs ranging between 0.125 and 8.0 µg/mL. An examination of their mechanisms of action by the newly established assay using LC-MS revealed that 1 and 2 inhibited serine palmitoyltransferase activity, which is involved in sphingolipid biosynthesis, with IC50 values of 224 and 24 nM, respectively.


Assuntos
Antifúngicos/química , Ácidos Graxos Monoinsaturados/química , Antifúngicos/farmacologia , Cromatografia Líquida , Ácidos Graxos Monoinsaturados/farmacologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Estereoisomerismo , Espectrometria de Massas em Tandem
6.
Rinsho Shinkeigaku ; 63(11): 748-753, 2023 Nov 23.
Artigo em Japonês | MEDLINE | ID: mdl-37880114

RESUMO

The patient was a 58-year-old Japanese man. At age 52 years, he was diagnosed with human immunodeficiency virus (HIV) infection and had been receiving highly active antiretroviral therapy (HAART). He presented to the emergency department with acute upper left and right lower extremity paralysis. Spinal cord magnetic resonance imaging showed intramedullary signal changes over three vertebral bodies in the cervical spinal cord. Anti-aquaporin-4 antibody was positive in serum, and neuromyelitis optica spectrum disorder (NMOSD) was diagnosed. Steroid pulse therapy and plasma exchange were performed but had limited effects. In Japan, there is no report of NMOSD after HIV infection treated with rituximab. Rituximab administration should be considered in refractory cases of NMOSD after HIV infection.


Assuntos
Infecções por HIV , Neuromielite Óptica , Masculino , Humanos , Pessoa de Meia-Idade , Neuromielite Óptica/tratamento farmacológico , Neuromielite Óptica/etiologia , Neuromielite Óptica/diagnóstico , Rituximab , Aquaporina 4 , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Autoanticorpos
7.
IEEE Int Conf Rehabil Robot ; 2023: 1-6, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941241

RESUMO

Patients with upper limb paralysis undergo various types of rehabilitation to reconstruct upper limb functions necessary for their return to daily life and social activities. Therefore, it is necessary to develop an effective rehabilitation support system using robotic technologies. In this study, we propose an EMG-driven hybrid rehabilitation system based on the estimation of intended motion using a probabilistic neural network. In the proposed system, the developed robot and functional electrical stimulation are controlled by estimating the patient's intention, which enables the intuitive learning of the appropriate control abilities of joint motions and muscle contraction patterns. In the experiments, hybrid and visual feedback training were conducted for pointing movements of the wrist joint of the non-dominant hand. The results confirmed that the proposed method provides effective training and has great potential for use in rehabilitation.


Assuntos
Robótica , Extremidade Superior , Humanos , Extremidade Superior/fisiologia , Robótica/métodos , Articulação do Punho/fisiologia , Redes Neurais de Computação , Movimento/fisiologia , Eletromiografia/métodos
8.
Front Neurosci ; 17: 1148336, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937688

RESUMO

Introduction: Neurofeedback (NFB) training and transcranial direct current stimulation (tDCS) have been shown to individually improve motor imagery (MI) abilities. However, the effect of combining both of them with MI has not been verified. Therefore, the aim of this study was to examine the effect of applying tDCS directly before MI with NFB. Methods: Participants were divided into an NFB group (n = 10) that performed MI with NFB and an NFB + tDCS group (n = 10) that received tDCS for 10 min before MI with NFB. Both groups performed 60 MI trials with NFB. The MI task was performed 20 times without NFB before and after training, and µ-event-related desynchronization (ERD) and vividness MI were evaluated. Results: µ-ERD increased significantly in the NFB + tDCS group compared to the NFB group. MI vividness significantly increased before and after training. Discussion: Transcranial direct current stimulation and NFB modulate different processes with respect to MI ability improvement; hence, their combination might further improve MI performance. The results of this study indicate that the combination of NFB and tDCS for MI is more effective in improving MI abilities than applying them individually.

9.
Front Neurosci ; 17: 1199398, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37483338

RESUMO

Introduction: Motor imagery (MI) is a method of imagining movement without actual movement, and its use in combination with motor execution (ME) enhances the effects of motor learning. Neurofeedback (NFB) is another method that promotes the effects of MI. This study aimed to investigate the effects of NFB on combined MI and ME (MIME) training in a standing postural control task. Methods: Sixteen participants were randomly divided into MIME and MIME + NFB groups and performed 10 trials of a postural control task on an unstable board, with nine trials of MI in between. Electroencephalogram was assessed during MI, and the MIME + NFB group received neurofeedback on the degree of MI via auditory stimulation. A postural control task using an unstable board was performed before and after the MIME task, during which postural instability was evaluated. Results: Postural instability was reduced after the MIME task in both groups. In addition, the root mean square, which indicates the sway of the unstable board, was significantly reduced in the MIME + NFB group compared to that in the MIME group. Conclusion: Our results indicate that MIME training is effective for motor learning of standing postural control. Furthermore, when MI and ME are combined, the feedback on the degree of MI enhances the learning effect.

10.
Biochim Biophys Acta ; 1812(7): 769-81, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21497196

RESUMO

The molecular mechanisms underlying the posttranslational modification of proteins in gastrointestinal cancer are still unknown. Here, we investigated the role of methylglyoxal modifications in gastrointestinal tumors. Methylglyoxal is a reactive dicarbonyl compound produced from cellular glycolytic intermediates that reacts non-enzymatically with proteins. By using a monoclonal antibody to methylglyoxal-modified proteins, we found that murine heat-shock protein 25 and human heat-shock protein 27 were the major adducted proteins in rat gastric carcinoma mucosal cell line and human colon cancer cell line, respectively. Furthermore, we found that heat-shock protein 27 was modified by methylglyoxal in ascending colon and rectum of patients with cancer. However, methylglyoxal-modified heat-shock protein 25/heat-shock protein 27 was not detected in non cancerous cell lines or in normal subject. Matrix-associated laser desorption/ionization mass spectrometry/mass spectrometry analysis of peptide fragments identified Arg-75, Arg-79, Arg-89, Arg-94, Arg-127, Arg-136, Arg-140, Arg-188, and Lys-123 as methylglyoxal modification sites in heat-shock protein 27 and in phosphorylated heat-shock protein 27. The transfer of methylglyoxal-modified heat-shock protein 27 into rat intestinal epithelial cell line RIE was even more effective in preventing apoptotic cell death than that of native control heat-shock protein 27. Furthermore, methylglyoxal modification of heat-shock protein 27 protected the cells against both the hydrogen peroxide- and cytochrome c-mediated caspase activation, and the hydrogen peroxide-induced production of intracellular reactive oxygen species. The levels of lactate converted from methylglyoxal were increased in carcinoma mucosal cell lines. Our results suggest that posttranslational modification of heat-shock protein 27 by methylglyoxal may have important implications for epithelial cell injury in gastrointestinal cancer.


Assuntos
Neoplasias Gastrointestinais/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Aldeído Pirúvico/metabolismo , Animais , Apoptose , Linhagem Celular , Linhagem Celular Tumoral , Neoplasias Gastrointestinais/patologia , Humanos , Imunoprecipitação , Proteômica , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
11.
Biol Pharm Bull ; 35(10): 1841-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23037175

RESUMO

The ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to discriminate laboratory-derived antibiotic-resistant bacterial strains of known genetic origin was examined. A computer-based cluster analysis of spectral data successfully discriminated the majority of single- as well as multiple-antibiotic-resistant Escherichia coli strains examined. Cluster analysis of Staphylococcus aureus strains with different levels of novobiocin resistance showed that as the degree of resistance increased similarity to the wild-type strain decreased. These results demonstrate that MALDI-TOF MS is capable of discriminating antibiotic-resistant bacterial strains and may have potential for differentiating bacterial strains with varying degrees of antibiotic-resistance.


Assuntos
Farmacorresistência Bacteriana , Escherichia coli , Staphylococcus aureus , Antibacterianos , Análise por Conglomerados , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
12.
Neurol Sci ; 33(2): 399-402, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21879327

RESUMO

Patients with Parkinson's disease (PD) may develop progressive dementia late in their clinical course. Dementia in PD is mostly related to neuropathological findings of extensive Lewy bodies (LBs), with or without the coexistence of Alzheimer's disease (AD) pathology. Aphasia has been reported in patients with LB diseases with AD pathology; however, there have been no reports of typical PD patients developing progressive aphasia during their clinical course. We describe a female PD patient who later developed progressive conduction aphasia characterized by phonemic paraphasia and disturbance in repetition of short sentences without disturbance in writing or auditory comprehension. No episodes of fluctuations of attention, memory complaints, or planning errors were observed. She experienced episodes of visual hallucination. Her low scores on the Mini-Mental State Examination suggested impairment of orientation and attention, and her scores on Raven's Coloured Progressive Matrices test indicated impaired visuospatial functions. However, her cognitive deficits were not sufficiently severe to impair her daily life. Brain magnetic resonance images revealed atrophy of the left superior temporal gyrus and widening of the left sylvian fissure. [(18)F]-fluorodeoxyglucose positron emission tomography revealed glucose hypometabolism in the left cerebral hemisphere. These findings may be related to conduction aphasia. During the progression of PD lesions, the brainstem LB is assumed to take an upward course, extend to the limbic system, and then extend to the neocortex. Conduction aphasia observed in our patient may be associated with an unusual progression of the LB pathology from the brainstem to the left temporoparietal lobe.


Assuntos
Afasia/etiologia , Transtornos Parkinsonianos/complicações , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Fluordesoxiglucose F18 , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons
13.
PLoS One ; 17(1): e0262181, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995315

RESUMO

Multiple cameras are used to resolve occlusion problem that often occur in single-view human activity recognition. Based on the success of learning representation with deep neural networks (DNNs), recent works have proposed DNNs models to estimate human activity from multi-view inputs. However, currently available datasets are inadequate in training DNNs model to obtain high accuracy rate. Against such an issue, this study presents a DNNs model, trained by employing transfer learning and shared-weight techniques, to classify human activity from multiple cameras. The model comprised pre-trained convolutional neural networks (CNNs), attention layers, long short-term memory networks with residual learning (LSTMRes), and Softmax layers. The experimental results suggested that the proposed model could achieve a promising performance on challenging MVHAR datasets: IXMAS (97.27%) and i3DPost (96.87%). A competitive recognition rate was also observed in online classification.


Assuntos
Atenção/fisiologia , Atividades Humanas/estatística & dados numéricos , Aprendizagem/fisiologia , Memória/fisiologia , Redes Neurais de Computação , Reconhecimento Psicológico , Humanos
14.
J Mass Spectrom ; 57(6): e4831, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35562642

RESUMO

Frozen section examination could provide pathological diagnosis for surgery of thyroid nodules, which is time-consuming, skill- and experience-dependent. This study developed a rapid classification method for thyroid nodules and machine learning. Total 69 tissues were collected including 43 nodules and 26 nodule-adjacent tissues. Intraoperative frozen section was first performed to give accurate diagnosis, and the rest frozen specimen were pretreated for probe electrospray ionization mass measurement. By multivariate analysis of mass scan data, a series compounds were found downregulated in the extraction solution of papillary thyroid carcinoma (PTC), but some were found upregulated by mass spectrometry imaging. m/z 758.5713 ([PC[34:2] + H]+ ), m/z 772.5845 ([PC[32:0] + K]+ ), and m/z 786.6037 ([PC[36:2] + H]+ ) were firstly identified as potential biomarkers for nodular goiter (NG). Machine learning was employed by means of support vector machine (SVM) and random forest (RF) algorithms. For classification of PTC from NG, SVM and RF algorithms exhibited the same performance and the concordance was 94.2% and 94.4% between prediction and pathological diagnosis with positive and negative mass dataset, respectively. For the classification of PTC from PTC adjacent tissues, SVM was better than RF and the concordance was 93.8% and 83.3% with positive and negative mass dataset, respectively. With the identified compounds as training features, the sensitivity and specificity are 87.5% and 88.9% for the test set. The developed method could also correctly predict the malignancy of one medullary thyroid carcinoma and one adenomatous goiter (benign). The diagnosis time is about 10 min for one specimen, and it is very promising for the intraoperative diagnosis of papillary thyroid carcinoma.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Aprendizado de Máquina , Espectrometria de Massas por Ionização por Electrospray , Câncer Papilífero da Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia
16.
Biol Pharm Bull ; 34(3): 430-2, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21372397

RESUMO

We evaluated the capability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to discriminate twelve Escherichia strains: E. blattae, E. fergusonii, E. hermanii and nine E. coli, whose ribosomal RNA (rRNA) gene sequence homologies are in the range of 96-100%. Similarities obtained by MALDI-TOF MS were found to be 78-92% among the E. coli strains, and 74% between E. coli and E. fergusonii. E. blattae and E. hermanii showed only 32% similarity when compared to the other species. Thus, MALDI-TOF MS provides capability of distinguishing bacterial species or even strains possessing highly conserved rRNA gene sequences.


Assuntos
Técnicas de Tipagem Bacteriana/métodos , Sequência de Bases , DNA Bacteriano , Escherichia coli/genética , Genes de RNAr , Espectrometria de Massas/métodos , Homologia de Sequência , Especificidade da Espécie , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
17.
Sci Rep ; 11(1): 7324, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795710

RESUMO

There is an urgent need for the development of ways to address the major issue of falls among today's globally aging population. The authors here outline a new approach referred to as virtual light-touch contact to mitigate postural sway during ambulatory and stationary periods, and propose a wearable light-touch (WLT) system featuring a virtual partition around the user that allows determination of virtual forces resulting from related contact. The data produced are used to create vibrotactile fingertip feedback, which supports comprehensive perception of the partition. Non-impaired subjects were recruited to support evaluation of the prototype system (incorporating tactile stimulation and motion-capture technology), with outcomes showing successful mitigation of postural sway in a heel-to-toe tandem stance. Research performed with 150 able-bodied volunteers to validate the performance of the new set-up (incorporating an acceleration sensor and a voice coil motor to render the light-touch effect) suggested that the proposed WLT approach supports human balance on a level comparable to that of the light-touch effect.


Assuntos
Engenharia Biomédica/métodos , Equilíbrio Postural/fisiologia , Propriocepção/fisiologia , Tato/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Impedância Elétrica , Dedos/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Postura/fisiologia , Pressão , Medicina Preventiva/métodos , Suporte de Carga/fisiologia , Adulto Jovem
18.
Sci Rep ; 11(1): 22012, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34759296

RESUMO

Previous studies have found that Autism Spectrum Disorder (ASD) children scored lower during a Go/No-Go task and faced difficulty focusing their gaze on the speaker's face during a conversation. To date, however, there has not been an adequate study examining children's response and gaze during the Go/No-Go task to distinguish ASD from typical children. We investigated typical and ASD children's gaze modulation when they played a version of the Go/No-Go game. The proposed system represents the Go and the No-Go stimuli as chicken and cat characters, respectively. It tracks children's gaze using an eye tracker mounted on the monitor. Statistically significant between-group differences in spatial and auto-regressive temporal gaze-related features for 21 ASD and 31 typical children suggest that ASD children had more unstable gaze modulation during the test. Using the features that differ significantly as inputs, the AdaBoost meta-learning algorithm attained an accuracy rate of 88.6% in differentiating the ASD subjects from the typical ones.


Assuntos
Atenção/fisiologia , Transtorno do Espectro Autista/diagnóstico , Fixação Ocular , Inibição Psicológica , Algoritmos , Transtorno do Espectro Autista/psicologia , Pré-Escolar , Tecnologia de Rastreamento Ocular , Feminino , Humanos , Japão , Masculino , Desempenho Psicomotor
19.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 3709-3712, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34892042

RESUMO

This paper proposes an evaluation/treatment sup-port system enabling automatic determination of wound evaluation indices from RGB-depth images and fully convolutional networks (FCNs). Segmentation experiments based on wound images and surface area determination experiments based on artificial images showed reduced errors and smaller parameters/higher levels of tissue classification than with previous approaches (proposed: 65.8 %; conventional: 60.2 %), thereby demonstrating the effectiveness of the technique.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação
20.
Comput Methods Programs Biomed ; 199: 105838, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33421664

RESUMO

BACKGROUND AND OBJECTIVES: The number of preterm babies is steadily growing world-wide and these neonates are at risk of neuro-motor-cognitive deficits. The observation of spontaneous movements in the first three months of age is known to predict such risk. However, the analysis by specifically trained physiotherapists is not suited for the clinical routine, motivating the development of simple computerized video analysis systems, integrated with a well-structured Biobank to make available for preterm babies a growing service with diagnostic, prognostic and epidemiological purposes. METHODS: MIMAS (Markerless Infant Movement Analysis System) is a simple, low-cost system of video analysis of spontaneous movements of newborns in their natural environment, based on a single standard RGB camera, without markers attached to the body. The original videos are transformed into binarized sequences highlighting the silhouette of the baby, in order to minimize the illumination effects and increase the robustness of the analysis; such sequences are then coded by a large set of parameters (39) related to the spatial and spectral changes of the silhouette. The parameter vectors of each baby were stored in the Biobank together with related clinical information. RESULTS: The preliminary test of the system was carried out at the Gaslini Pediatric Hospital in Genoa, where 46 preterm (PT) and 21 full-term (FT) babies (as controls) were recorded at birth (T0) and 8-12 weeks thereafter (T1). A simple statistical analysis of the data showed that the coded parameters are sensitive to the degree of maturation of the newborns (comparing T0 with T1, for both PT and FT babies), and to the conditions at birth (PT vs. FT at T0), whereas this difference tends to vanish at T1. Moreover, the coding method seems also able to detect the few 'abnormal' preterm babies in the PT populations that were analyzed as specific case studies. CONCLUSIONS: Preliminary results motivate the adoption of this tool in clinical practice allowing for a systematic accumulation of cases in the Biobank, thus for improving the accuracy of data analysis performed by MIMAS and ultimately allowing the adoption of data mining techniques.


Assuntos
Recém-Nascido Prematuro , Movimento , Criança , Humanos , Lactente , Recém-Nascido
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA