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1.
Gene ; 806: 145922, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34454032

RESUMO

Gastric cancer (GC)-derived cell lines were generally used in basic cancer research and drug screening. However, it is always concerned about the difference between cultured cells and primary tumor by oncologists. To address this question, we compared differentially expressed genes (DEGs) in primary cancers, healthy tissues, and cell lines both in vitro and in silico. Seven reported genes with decreased expression in GCs by DNA methylation were analyzed in our cohort studies and experimentally validation. Selected datasets from TCGA (The Cancer Genome Atlas), CCLE (The Broad Institute Cancer Cell Line Encyclopedia), and GTEx (The Genotype-Tissue Expression project) were used to represent GCs, GC-derived cell lines, and healthy tissues respectively in the in silico analysis. Thirty gastric tissues together with six cell lines were used for validations. Unexpectedly, we experimentally found that reported cancer-related downregulated genes were only found in cancer cell lines but not in biopsies. The unchanged gene expressions in primary GCs were generally consistent with our cohort study, using information from cancerous (TCGA) and healthy tissues (GETx). Substantial differences were also found between DEGs of cancer tissues (TGCA)/ healthy tissues (GTEx) pair and cell lines (CCLE)/ healthy tissues (GTEx) pair, which confirmed the significant differences between primary cancer and cancer cell lines. Moreover, elevated expression of YWHAQ (14-3-3 δ) and THBS1 were observed in the GC biopsies, which might be potential biomarkers for GC diagnosis, considering the increased YWHAQ and THBS1 associated with poor survival rates in gastric cancer patients. In sum, it is suggested that cautions should be taken when using GC cell lines to study genes that show great differences between cell lines and tissues.


Assuntos
Proteínas 14-3-3/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/genética , Neoplasias Gástricas/genética , Trombospondinas/genética , Proteínas 14-3-3/metabolismo , Idoso , Atlas como Assunto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Metilação de DNA , Conjuntos de Dados como Assunto , Epigênese Genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Proteínas de Neoplasias/metabolismo , Cultura Primária de Células , Prognóstico , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Análise de Sobrevida , Trombospondinas/metabolismo , Células Tumorais Cultivadas
2.
Arch Virol ; 166(11): 3221-3224, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34515865

RESUMO

Equine hepacivirus (EqHV) is a newly discovered hepatitis C virus-like virus that can infect equines. EqHV strains circulating worldwide have been classified into subtypes 1-3. In previous studies, we detected the presence of EqHV strains of subtype 1 and 3 in China. To determine whether EqHV strains of subtype 2 are prevalent in China, serum samples were collected from 133 racehorses in Guangdong province in 2021 and were tested for EqHV RNA by RT-PCR, and the positive rate was 9% (12/133). Sequencing of the NS3 gene revealed that one field strain (GD2021) had a high degree of genetic similarity to EqHV strains of subtype 2. Subsequent genome sequencing and analysis demonstrated that strain GD2021 belongs to subtype 2. The present study enriches our knowledge about the genetic diversity of EqHV in China.

3.
Virus Res ; 304: 198529, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34363851

RESUMO

Parvovirus is a common element of the feline virus group and usually causes gastroenteritis and leukopenia in cats. In this study, we identified a novel protoparvovirus from the Chinese domestic cats, which is genetically similar to canine bufavirus (98.0%-99.8%), but sharing low amino acid identities in the viral structural proteins 2 (VP2) (36.1-37.2%) to the well-known canine parvovirus type 2 and feline panleukopenia virus. This virus was provisionally designated as feline bufavirus (FBuV). Screening of fecal samples revealed a prevalence of 7.4% (19/257) in domestic cats. Diarrhea was present in 52.6% (10/19) of cats positive for FBuV. However, statistical analysis showed no association between FBuV and clinical signs. VP2 gene of the 19 field FBuV was sequenced and phylogenetic analysis demonstrated that FBuV determined from China had a genetic diversity. This study will strengthen the understanding of the epidemiology and genetic diversity of bufavirus and provide a foundation for further studies.

4.
Appl Environ Microbiol ; 87(13): e0029421, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33893110

RESUMO

Exploring unknown glycosyltransferases (GTs) is important for compound structural glycodiversification during the search for drug candidates. Piericidin glycosides have been reported to have potent bioactivities; however, the GT responsible for piericidin glucosylation remains unknown. Herein, BmmGT1, a macrolide GT with broad substrate selectivity and isolated from Bacillus methylotrophicus B-9987, was found to be able to glucosylate piericidin A1 in vitro. Next, the codon-optimized GT gene sbmGT1, which was designed based on BmmGT1, was heterologously expressed in the piericidin producer Streptomyces youssoufiensis OUC6819. Piericidin glycosides thus significantly accumulated, leading to the identification of four new glucopiericidins (compounds 3, 4, 6, and 7). Furthermore, using BmmGT1 as the probe, GT1507 was identified in the genome of S. youssoufiensis OUC6819 and demonstrated to be associated with piericidin glucosylation; the overexpression of this gene led to the identification of another new piericidin glycoside, N-acetylglucosamine-piericidin (compound 8). Compounds 4, 7, and 8 displayed cytotoxic selectivity toward A549, A375, HCT-116, and HT-29 solid cancer cell lines compared to the THP-1 lymphoma cell line. Moreover, database mining of GT1507 homologs revealed their wide distribution in bacteria, mainly in those belonging to the high-GC Gram-positive and Firmicutes clades, thus representing the potential for identification of novel tool enzymes for compound glycodiversification. IMPORTANCE Numerous bioactive natural products are appended with sugar moieties and are often critical for their bioactivities. Glycosyltransferases (GTs) are powerful tools for the glycodiversification of natural products. Although piericidin glycosides display potent bioactivities, the GT involved in glucosylation is unclear. In this study, five new piericidin glycosides (compounds 3, 4, 6, 7, and 8) were generated following the overexpression of GT-coding genes in a piericidin producer. Three of them (compounds 4, 7, and 8) displayed cytotoxic selectivity. Notably, GT1507 was demonstrated to be related to piericidin glucosylation in vivo. Furthermore, mining of GT1507 homologs from the GenBank database revealed their wide distribution across numerous bacteria. Our findings would greatly facilitate the exploration of GTs to glycodiversify small molecules in the search for drug candidates.


Assuntos
Proteínas de Bactérias/genética , Glicosídeos/farmacologia , Glicosiltransferases/genética , Piridinas/farmacologia , Bactérias/genética , Bactérias/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica , Glicosídeos/metabolismo , Glicosilação , Humanos , Piridinas/metabolismo
5.
Vet Microbiol ; 254: 108997, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33524810

RESUMO

Canine influenza (CI) is a contagious respiratory disease in dogs, which poses a threat to canine health. A safe, high-yield vaccine seed virus is critical for CI vaccine development. We developed a PR8-based reassortant H3N2 canine influenza virus (RT CIV) using the reverse genetic method and evaluated its yield in canine kidney epithelial (MDCK) cells, Vero cells, and specific pathogen-free (SPF) chicken embryos. Mice and dogs were infected with RT CIV, and the pathogenicity was evaluated. The viral titers of RT CIV increased in MDCK cells, Vero cells, and SPF chicken embryos; the HA yield in SPF chicken embryos increased 4-fold. However, RT CIV was not lethal to mice, and it showed similar virulence as wild-type CIV. RT CIV also showed minimal pathogenicity in dogs, which manifested as mild fever and rhinorrhea for the first two days post-infection. Thus, RT CIV carrying the internal gene cassette from PR8 showed almost no pathogenicity in dogs. And the reassortant virus inactivated vaccine could provide complete protection against H3N2 CIV. To our knowledge, this is the first report on the pathogenicity of PR8-based reassortant H3N2 CIV in dogs. These studies are relevant for developing a high-yield and safe CI vaccine.


Assuntos
Doenças do Cão/prevenção & controle , Doenças do Cão/virologia , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Infecções por Orthomyxoviridae/veterinária , Vírus Reordenados/genética , Animais , Anticorpos Antivirais/sangue , Chlorocebus aethiops , Doenças do Cão/imunologia , Cães , Feminino , Células HEK293 , Humanos , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Vírus Reordenados/patogenicidade , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia , Células Vero , Replicação Viral
6.
Mol Biol Evol ; 38(6): 2582-2596, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-33616658

RESUMO

Human natural killer (NK) cells are essential for controlling infection, cancer, and fetal development. NK cell functions are modulated by interactions between polymorphic inhibitory killer cell immunoglobulin-like receptors (KIR) and polymorphic HLA-A, -B, and -C ligands expressed on tissue cells. All HLA-C alleles encode a KIR ligand and contribute to reproduction and immunity. In contrast, only some HLA-A and -B alleles encode KIR ligands and they focus on immunity. By high-resolution analysis of KIR and HLA-A, -B, and -C genes, we show that the Chinese Southern Han (CHS) are significantly enriched for interactions between inhibitory KIR and HLA-A and -B. This enrichment has had substantial input through population admixture with neighboring populations, who contributed HLA class I haplotypes expressing the KIR ligands B*46:01 and B*58:01, which subsequently rose to high frequency by natural selection. Consequently, over 80% of Southern Han HLA haplotypes encode more than one KIR ligand. Complementing the high number of KIR ligands, the CHS KIR locus combines a high frequency of genes expressing potent inhibitory KIR, with a low frequency of those expressing activating KIR. The Southern Han centromeric KIR region encodes strong, conserved, inhibitory HLA-C-specific receptors, and the telomeric region provides a high number and diversity of inhibitory HLA-A and -B-specific receptors. In all these characteristics, the CHS represent other East Asians, whose NK cell repertoires are thus enhanced in quantity, diversity, and effector strength, likely augmenting resistance to endemic viral infections.


Assuntos
Evolução Molecular , Genes MHC Classe I , Células Matadoras Naturais/fisiologia , Receptores KIR/genética , China , Antígenos HLA-A/metabolismo , Antígenos HLA-B/metabolismo , Humanos , Receptores KIR/metabolismo
7.
Front Immunol ; 11: 2064, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133062

RESUMO

To effectively defend against microbial pathogens, the host cells mount antiviral innate immune responses by producing interferons (IFNs), and hundreds of IFN-stimulated genes (ISGs). Upon recognition of cytoplasmic viral or bacterial DNAs and abnormal endogenous DNAs, the DNA sensor cGAS synthesizes 2',3'-cGAMP that induces STING (stimulator of interferon genes) undergoing conformational changes, cellular trafficking, and the activation of downstream factors. Therefore, STING plays a pivotal role in preventing microbial pathogen infection by sensing DNAs during pathogen invasion. This review is dedicated to the recent advances in the dynamic regulations of STING activation, intracellular trafficking, and post-translational modifications (PTMs) by the host and microbial proteins.


Assuntos
DNA Viral/imunologia , Proteínas de Membrana/metabolismo , Viroses/metabolismo , Regulação Alostérica , Animais , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Proteínas de Membrana/genética , Nucleotídeos Cíclicos/metabolismo , Processamento de Proteína Pós-Traducional
8.
Sci Rep ; 10(1): 20294, 2020 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-33219347

RESUMO

Pectus excavatum (PE) is one of the most common chest wall defects. Accurate assessment of PE deformities is critical for effective surgical intervention. Index-based evaluations have become the standard for objectively estimating PE, however, these indexes cannot represent the whole information of chest CT images and may associated with significant error due to the individual differences. To overcome these limitations, this paper developed a computer-aided diagnosis (CAD) system based on the convolutional neural network (CNN) to automatically learn discriminative features and classify PE images. We also adopted block-wise fine-tuning methods based on the transfer learning strategy to reduce the potential risk of overfitting caused by limited data and experimentally explored the best fine-tuning degree. Our method achieved a high level of classification accuracy with 94.76% for PE diagnosis. Furthermore, we proposed a majority rule-based voting method to provide a comprehensively diagnostic results for each patient, which integrated the classification results of the whole thorax. The promising results support the feasibility of our proposed CNN-based CAD system for automatic PE diagnosis, which paves a way for comprehensive assessments of PE in clinics.


Assuntos
Aprendizado Profundo , Tórax em Funil/diagnóstico , Interpretação de Imagem Assistida por Computador/métodos , Esterno/diagnóstico por imagem , Parede Torácica/diagnóstico por imagem , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Esterno/anormalidades , Parede Torácica/anormalidades , Tomografia Computadorizada por Raios X , Adulto Jovem
9.
Virus Genes ; 56(6): 777-780, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32964346

RESUMO

Equine Hepacivirus (EqHV) is a newly discovered equine virus that is classified under the Hepacivirus genus of the Flaviviridae family. There are three sub-types of EqHV worldwide namely; sub-types 1-3. The majority of EqHV sub-type 1 strains were found in China. While different sub-types have been found in Japan and USA, therefore, to investigate whether the other sub-types of EqHV strains were present in China, a total of 60 horse serum samples were collected and screened for EqHV RNA through RT-PCR. The results revealed that 19 serum samples were RNA-positive (19/60) and the EqHV detection rate was 31.67%. One EqHV strain named GD23 was obtained and its near-complete genome sequence was acquired. Analysis of nucleotide p-distance with reference to the entire polyprotein gene revealed that GD23 was classified into sub-type 3. In addition, the phylogenetic analysis demonstrated that GD23 was clustered together with EqHV strains of sub-type 3 in other countries. The present study is the first to identify an EqHV sub-type 3 strain in China.

10.
Front Neurorobot ; 14: 32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754025

RESUMO

Background and Objective: Electroencephalography (EEG) can be used to control machines with human intention, especially for paralyzed people in rehabilitation exercises or daily activities. Some effort was put into this but still not enough for online use. To improve the practicality, this study aims to propose an efficient control method based on P300, a special EEG component. Moreover, we have developed an upper-limb assist robot system with the method for verification and hope to really help paralyzed people. Methods: We chose P300, which is highly available and easily accepted to obtain the user's intention. Preprocessing and spatial enhancement were firstly implemented on raw EEG data. Then, three approaches- linear discriminant analysis, support vector machine, and multilayer perceptron -were compared in detail to accomplish an efficient P300 detector, whose output was employed as a command to control the assist robot. Results: The method we proposed achieved an accuracy of 94.43% in the offline test with the data from eight participants. It showed sufficient reliability and robustness with an accuracy of 80.83% and an information transfer rate of 15.42 in the online test. Furthermore, the extended test showed remarkable generalizability of this method that can be used in more complex application scenarios. Conclusion: From the results, we can see that the proposed method has great potential for helping paralyzed people easily control an assist robot to do numbers of things.

11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(8): 895-897, 2020 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-32761604

RESUMO

OBJECTIVE: To report on a novel KIR3DL3 allele identified in a southern Han Chinese individual. METHODS: Peripheral blood sample was collected from a voluntary blood donor with inconclusive result by KIR3DL3 sequence-based typing (SBT). Total mRNA was extracted and subjected to reverse transcription to obtain KIR3DL3 cDNA, which was then amplified by PCR with a pair of KIR3DL3-specific primers. The product was subjected to cDNA cloning and sequencing. RESULTS: cDNA cloning and sequencing have identified a wide-type KIR3DL3*00802 allele and a novel KIR3DL3*064 allele. The latter differed from KIR3DL3*00601 by a missense variant at codon 374[c.1184 C>T (p.Thr374Ile)] in exon 9. The novel KIR3DL3 allele has been officially assigned by the KIR subcommittee of World Health Organization Nomenclature Committee for factors of HLA system. CONCLUSION: cDNA cloning and sequencing may be used to distinguish inconclusive results in KIR3DL3 SBT in order to identify novel KIR alleles.


Assuntos
Alelos , Receptores KIR/genética , Sequência de Bases , Clonagem Molecular , Códon , DNA Complementar/genética , Humanos , Mutação de Sentido Incorreto , Análise de Sequência de DNA
12.
Arch Virol ; 165(11): 2699-2702, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32851431

RESUMO

Canine bufavirus (CBuV) is a novel protoparvovirus of dogs that was first reported in 2018 in Italy. The prevalence and genetic diversity of CBuV in China are not clear. In this study, a total of 115 canine fecal samples were collected from northern China in 2019, and two of the samples tested positive for CBuV DNA by PCR. These two field CBuV strains were designated Henan38 and Henan44. The complete genomic sequences of Henan38 and Henan44 were obtained by gap-filling PCR, sequenced, and assembled. Phylogenetic analysis demonstrated that the two strains clustered together in a novel group that was distant from previously reported CBuV strains. This study will strengthen our understanding of the epidemiology and genetic diversity of CBuV in China.


Assuntos
Evolução Molecular , Variação Genética , Infecções por Parvoviridae/veterinária , Parvovirus Canino/classificação , Filogenia , Animais , Sequência de Bases , China , Doenças do Cão/virologia , Cães , Fezes/virologia , Genoma Viral , Parvovirus Canino/isolamento & purificação
13.
J Neuroeng Rehabil ; 17(1): 58, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32345335

RESUMO

BACKGROUND: Compensations are commonly observed in patients with stroke when they engage in reaching without supervision; these behaviors may be detrimental to long-term functional improvement. Automatic detection and reduction of compensation cab help patients perform tasks correctly and promote better upper extremity recovery. OBJECTIVE: Our first objective is to verify the feasibility of detecting compensation online using machine learning methods and pressure distribution data. Second objective was to investigate whether compensations of stroke survivors can be reduced by audiovisual or force feedback. The third objective was to compare the effectiveness of audiovisual and force feedback in reducing compensation. METHODS: Eight patients with stroke performed reaching tasks while pressure distribution data were recorded. Both the offline and online recognition accuracy were investigated to assess the feasibility of applying a support vector machine (SVM) based compensation detection system. During reduction of compensation, audiovisual feedback was delivered using virtual reality technology, and force feedback was delivered through a rehabilitation robot. RESULTS: Good classification performance was obtained in online compensation recognition, with an average F1-score of over 0.95. Based on accurate online detection, real-time feedback significantly decreased compensations of patients with stroke in comparison with no-feedback condition (p < 0.001). Meanwhile, the difference between audiovisual and force feedback was also significant (p < 0.001) and force feedback was more effective in reducing compensation in patients with stroke. CONCLUSIONS: Accurate online recognition validated the feasibility of monitoring compensations using machine learning algorithms and pressure distribution data. Reliable online detection also paved the way for reducing compensations by providing feedback to patients with stroke. Our findings suggested that real-time feedback could be an effective approach to reducing compensatory patterns and force feedback demonstrated a more enviable potential compared with audiovisual feedback.


Assuntos
Adaptação Fisiológica/fisiologia , Sistemas On-Line , Reabilitação do Acidente Vascular Cerebral/instrumentação , Reabilitação do Acidente Vascular Cerebral/métodos , Adulto , Idoso , Retroalimentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas On-Line/instrumentação , Projetos Piloto , Acidente Vascular Cerebral/fisiopatologia , Máquina de Vetores de Suporte , Sobreviventes , Extremidade Superior/fisiopatologia , Realidade Virtual
15.
IEEE J Biomed Health Inform ; 24(9): 2630-2638, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31902785

RESUMO

OBJECTIVES: Compensations are commonly employed by patients with stroke during rehabilitation without therapist supervision, leading to suboptimal recovery outcomes. This study investigated the feasibility of the real-time monitoring of compensation in patients with stroke by using pressure distribution data and machine learning algorithms. Whether trunk compensation can be reduced by combining the online detection of compensation and haptic feedback of a rehabilitation robot was also investigated. METHODS: Six patients with stroke did three forms of reaching movements while pressure distribution data were recorded as Dataset1. A support vector machine (SVM) classifier was trained with features extracted from Dataset1. Then, two other patients with stroke performed reaching tasks, and the SVM classifier trained by Dataset1 was employed to classify the compensatory patterns online. Based on the real-time monitoring of compensation, a rehabilitation robot provided an assistive force to patients with stroke to reduce compensations. RESULTS: Good classification performance (F1 score > 0.95) was obtained in both offline and online compensation analysis using the SVM classifier and pressure distribution data of patients with stroke. Based on the real-time detection of compensatory patterns, the angles of trunk rotation, trunk lean-forward and trunk-scapula elevation decreased by 46.95%, 32.35% and 23.75%, respectively. CONCLUSION: High classification accuracies verified the feasibility of detecting compensation in patients with stroke based on pressure distribution data. Since the validity and reliability of the online detection of compensation has been verified, this classifier can be incorporated into a rehabilitation robot to reduce trunk compensations in patients with stroke.

17.
Front Neurosci ; 13: 1250, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824250

RESUMO

Stroke patients often use trunk to compensate for impaired upper limb motor function during upper limb rehabilitation training, which results in a reduced rehabilitation training effect. Detecting trunk compensations can improve the effect of rehabilitation training. This study investigates the feasibility of a surface electromyography-based trunk compensation detection (sEMG-bTCD) method. Five healthy subjects and nine stroke subjects with cognitive and comprehension skills were recruited to participate in the experiments. The sEMG signals from nine superficial trunk muscles were collected during three rehabilitation training tasks (reach-forward-back, reach-side-to-side, and reach-up-to-down motions) without compensation and with three common trunk compensations [lean-forward (LF), trunk rotation (TR), and shoulder elevation (SE)]. Preprocessing like filtering, active segment detection was performed and five time domain features (root mean square, variance, mean absolute value (MAV), waveform length, and the fourth order autoregressive model coefficient) were extracted from the collected sEMG signals. Excellent TCD performance was achieved in healthy participants by using support vector machine (SVM) classifier (LF: accuracy = 94.0%, AUC = 0.97, F1 = 0.94; TR: accuracy = 95.8%, AUC = 0.99, F1 = 0.96; SE: accuracy = 100.0%, AUC = 1.00, F1 = 1.00). By using SVM classifier, TCD performance in stroke participants was also obtained (LF: accuracy = 74.8%, AUC = 0.90, F1 = 0.73; TR: accuracy = 67.1%, AUC = 0.85, F1 = 0.71; SE: accuracy = 91.3%, AUC = 0.98, F1 = 0.90). Compared with the methods based on cameras or inertial sensors, better detection performance was obtained in both healthy and stroke participants. The results demonstrated the feasibility of the sEMG-bTCD method, and it helps to prompt the stroke patients to correct their incorrect posture, thereby improving the effectiveness of rehabilitation training.

18.
J Neuroeng Rehabil ; 16(1): 131, 2019 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-31684970

RESUMO

BACKGROUND: Compensatory movements are commonly employed by stroke survivors during seated reaching and may have negative effects on their long-term recovery. Detecting compensation is useful for coaching the patient to reduce compensatory trunk movements and improving the motor function of the paretic arm. Sensor-based and camera-based systems have been developed to detect compensatory movements, but they still have some limitations, such as causing object obstructions, requiring complex setups and raising privacy concerns. To overcome these drawbacks, this paper proposes a compensatory movement detection system based on pressure distribution data and is unobtrusive, simple and practical. Machine learning algorithms were applied to classify compensatory movements automatically. Therefore, the purpose of this study was to develop and test a pressure distribution-based system for the automatic detection of compensation movements of stroke survivors using machine learning algorithms. METHODS: Eight stroke survivors performed three types of reaching tasks (back-and-forth, side-to-side, and up-and-down reaching tasks) with both the healthy side and the affected side. The pressure distribution data were recorded, and five features were extracted for classification. The k-nearest neighbor (k-NN) and support vector machine (SVM) algorithms were applied to detect and categorize the compensatory movements. The surface electromyography (sEMG) signals of nine trunk muscles were acquired to provide a detailed description and explanation of compensatory movements. RESULTS: Cross-validation yielded high classification accuracies (F1-score>0.95) for both the k-NN and SVM classifiers in detecting compensation movements during all the reaching tasks. In detail, an excellent performance was achieved in discriminating between compensation and noncompensation (NC) movements, with an average F1-score of 0.993. For the multiclass classification of compensatory movement patterns, an average F1-score of 0.981 was achieved in recognizing the NC, trunk lean-forward (TLF), trunk rotation (TR) and shoulder elevation (SE) movements. CONCLUSIONS: Good classification performance in detecting and categorizing compensatory movements validated the feasibility of the proposed pressure distribution-based system. Reliable classification accuracy achieved by the machine learning algorithms indicated the potential to monitor compensation movements automatically by using the pressure distribution-based system when stroke survivors perform seated reaching tasks.


Assuntos
Movimento , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/fisiopatologia , Adulto , Idoso , Algoritmos , Fenômenos Biomecânicos , Eletromiografia , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Pressão , Desempenho Psicomotor , Máquina de Vetores de Suporte , Tronco/fisiopatologia , Extremidade Superior/fisiopatologia
20.
Front Immunol ; 10: 1646, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379844

RESUMO

Interactions of human natural killer (NK) cell inhibitory receptors with polymorphic HLA-A, -B and -C molecules educate NK cells for immune surveillance against tumor cells. The KIR A haplotype encodes a distinctive set of HLA-specific NK cell inhibiting receptors having strong influence on immunity. We observed higher frequency of KIR A homozygosity among 745 healthy Chinese Southern Han than 836 adult patients representing three types of leukemia: ALL (OR = 0.68, 95% CI = 0.52-0.89, p = 0.004), AML (OR = 0.76, 95% CI = 0.59-0.98, p = 0.034), and CML (OR = 0.72 95% CI = 0.51-1.0, ns). We observed the same trend for NHL (OR = 0.47 95% CI = 0.26-0.88 p = 0.017). For ALL, the protective effect of the KIR AA genotype was greater in the presence of KIR ligands C1 (Pc = 0.01) and Bw4 (Pc = 0.001), which are tightly linked in East Asians. By contrast, the C2 ligand strengthened protection from CML (Pc = 0.004). NK cells isolated from KIR AA individuals were significantly more cytotoxic toward leukemic cells than those from other KIR genotypes (p < 0.0001). These data suggest KIR allotypes encoded by East Asian KIR A haplotypes are strongly inhibitory, arming NK cells to respond to leukemogenic cells having altered HLA expression. Thus, the study of populations with distinct KIR and HLA distributions enlightens understanding of immune mechanisms that significantly impact leukemia pathogenesis.


Assuntos
Células Matadoras Naturais/imunologia , Leucemia/imunologia , Adulto , Grupo com Ancestrais do Continente Asiático , Criança , Feminino , Genótipo , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Masculino , Receptores KIR/imunologia
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