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1.
Sensors (Basel) ; 22(2)2022 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-35062641

RESUMO

Motion classification can be performed using biometric signals recorded by electroencephalography (EEG) or electromyography (EMG) with noninvasive surface electrodes for the control of prosthetic arms. However, current single-modal EEG and EMG based motion classification techniques are limited owing to the complexity and noise of EEG signals, and the electrode placement bias, and low-resolution of EMG signals. We herein propose a novel system of two-dimensional (2D) input image feature multimodal fusion based on an EEG/EMG-signal transfer learning (TL) paradigm for detection of hand movements in transforearm amputees. A feature extraction method in the frequency domain of the EEG and EMG signals was adopted to establish a 2D image. The input images were used for training on a model based on the convolutional neural network algorithm and TL, which requires 2D images as input data. For the purpose of data acquisition, five transforearm amputees and nine healthy controls were recruited. Compared with the conventional single-modal EEG signal trained models, the proposed multimodal fusion method significantly improved classification accuracy in both the control and patient groups. When the two signals were combined and used in the pretrained model for EEG TL, the classification accuracy increased by 4.18-4.35% in the control group, and by 2.51-3.00% in the patient group.


Assuntos
Amputados , Interfaces Cérebro-Computador , Aprendizado Profundo , Algoritmos , Eletroencefalografia , Eletromiografia , Humanos , Punho
2.
Dysphagia ; 36(6): 1054-1062, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33399994

RESUMO

The effectiveness of the chin tuck maneuver is still controversial, despite being widely used in clinical practice. The chin tuck maneuver has been shown to be able to reduce or eliminate aspiration in a group of patients with a number of favorable conditions, but its effectiveness in preventing or managing penetration remains unclear. This study was designed to investigate whether the chin tuck maneuver is effective in reducing penetration. Images from a videofluoroscopic swallowing study (VFSS) taken from 76 patients with penetration were collected and reviewed retrospectively. The severity of penetration was assessed by the penetration ratio (ratio of the penetration depth to the length of the epiglottis) measured and calculated from the images in which the deepest penetration was observed. The penetration ratio was significantly decreased in the chin tuck posture compared with the ratio in the neutral position (p = 0.001). Significant reducing effect was observed in 26 (34.2%) out of 76 patients. When comparing other parameters of VFSS, residues in the vallecular and pyriformis sinuses were less severe in the effective group. Chin tuck significantly decreased residues in both effective and ineffective group. The results demonstrate that the chin tuck maneuver can reduce penetration, but its effectiveness is limited.


Assuntos
Transtornos de Deglutição , Laringe , Queixo/diagnóstico por imagem , Deglutição , Transtornos de Deglutição/diagnóstico por imagem , Humanos , Laringe/diagnóstico por imagem , Estudos Retrospectivos
3.
J Biol Chem ; 291(27): 14199-14212, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27189941

RESUMO

The viral vector-mediated overexpression of the defined transcription factors, Brn4/Pou3f4, Sox2, Klf4, and c-Myc (BSKM), could induce the direct conversion of somatic fibroblasts into induced neural stem cells (iNSCs). However, viral vectors may be randomly integrated into the host genome thereby increasing the risk for undesired genotoxicity, mutagenesis, and tumor formation. Here we describe the generation of integration-free iNSCs from mouse fibroblasts by non-viral episomal vectors containing BSKM. The episomal vector-derived iNSCs (e-iNSCs) closely resemble control NSCs, and iNSCs generated by retrovirus (r-iNSCs) in morphology, gene expression profile, epigenetic status, and self-renewal capacity. The e-iNSCs are functionally mature, as they could differentiate into all the neuronal cell types both in vitro and in vivo Our study provides a novel concept for generating functional iNSCs using a non-viral, non-integrating, plasmid-based system that could facilitate their biomedical applicability.


Assuntos
Células-Tronco Neurais/citologia , Animais , Fibroblastos/citologia , Vetores Genéticos , Fator 4 Semelhante a Kruppel , Camundongos , Camundongos Endogâmicos C3H , Transfecção
4.
J Biol Chem ; 289(47): 32512-25, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25294882

RESUMO

The spinal cord does not spontaneously regenerate, and treatment that ensures functional recovery after spinal cord injury (SCI) is still not available. Recently, fibroblasts have been directly converted into induced neural stem cells (iNSCs) by the forced expression defined transcription factors. Although directly converted iNSCs have been considered to be a cell source for clinical applications, their therapeutic potential has not yet been investigated. Here we show that iNSCs directly converted from mouse fibroblasts enhance the functional recovery of SCI animals. Engrafted iNSCs could differentiate into all neuronal lineages, including different subtypes of mature neurons. Furthermore, iNSC-derived neurons could form synapses with host neurons, thus enhancing the locomotor function recovery. A time course analysis of iNSC-treated SCI animals revealed that engrafted iNSCs effectively reduced the inflammatory response and apoptosis in the injured area. iNSC transplantation also promoted the active regeneration of the endogenous recipient environment in the absence of tumor formation. Therefore, our data suggest that directly converted iNSCs hold therapeutic potential for treatment of SCI and may thus represent a promising cell source for transplantation therapy in patients with SCI.


Assuntos
Células-Tronco Pluripotentes Induzidas/transplante , Células-Tronco Neurais/transplante , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Embrião de Mamíferos/citologia , Potencial Evocado Motor/genética , Potencial Evocado Motor/fisiologia , Feminino , Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Imuno-Histoquímica , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos Endogâmicos C3H , Microscopia de Fluorescência , Regeneração Nervosa/genética , Regeneração Nervosa/fisiologia , Nestina/genética , Nestina/metabolismo , Células-Tronco Neurais/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/genética , Recuperação de Função Fisiológica/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Traumatismos da Medula Espinal/genética , Sinapses/metabolismo , Sinapses/fisiologia
5.
J Nanobiotechnology ; 13: 21, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25886153

RESUMO

BACKGROUND: Electrospinning is a simple and effective method for fabricating micro- and nanofiber matrices. Electrospun fibre matrices have numerous advantages for use as tissue engineering scaffolds, such as high surface area-to-volume ratio, mass production capability and structural similarity to the natural extracellular matrix (ECM). Therefore, electrospun matrices, which are composed of biocompatible polymers and various biomaterials, have been developed as biomimetic scaffolds for the tissue engineering applications. In particular, graphene oxide (GO) has recently been considered as a novel biomaterial for skeletal muscle regeneration because it can promote the growth and differentiation of myoblasts. Therefore, the aim of the present study was to fabricate the hybrid fibre matrices that stimulate myoblasts differentiation for skeletal muscle regeneration. RESULTS: Hybrid fibre matrices composed of poly(lactic-co-glycolic acid, PLGA) and collagen (Col) impregnated with GO (GO-PLGA-Col) were successfully fabricated using an electrospinning process. Our results indicated that the GO-PLGA-Col hybrid matrices were comprised of randomly-oriented continuous fibres with a three-dimensional non-woven porous structure. Compositional analysis showed that GO was dispersed uniformly throughout the GO-PLGA-Col matrices. In addition, the hydrophilicity of the fabricated matrices was significantly increased by blending with a small amount of Col and GO. The attachment and proliferation of the C2C12 skeletal myoblasts were significantly enhanced on the GO-PLGA-Col hybrid matrices. Furthermore, the GO-PLGA-Col matrices stimulated the myogenic differentiation of C2C12 skeletal myoblasts, which was enhanced further under the culture conditions of the differentiation media. CONCLUSIONS: Taking our findings into consideration, it is suggested that the GO-PLGA-Col hybrid fibre matrices can be exploited as potential biomimetic scaffolds for skeletal tissue engineering and regeneration because these GO-impregnated hybrid matrices have potent effects on the induction of spontaneous myogenesis and exhibit superior bioactivity and biocompatibility.


Assuntos
Materiais Biomiméticos/química , Colágeno/química , Grafite/química , Ácido Láctico/química , Mioblastos/citologia , Ácido Poliglicólico/química , Animais , Adesão Celular , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Proliferação de Células , Matriz Extracelular/química , Camundongos , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Músculo Esquelético/citologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Alicerces Teciduais , Difração de Raios X
6.
Dysphagia ; 29(4): 444-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24682308

RESUMO

Dysphagia affects up to half of stroke patients and increases the risk of pneumonia and fatal outcomes. In order to assess swallowing difficulty, videofluoroscopic swallowing study (VFSS) has traditionally been the gold standard. The purpose of this study was to compare the patterns of post-stroke swallowing difficulties according to the vascular territories involved in the stroke. One hundred and three patients who were diagnosed with first ischemic stroke by brain magnetic resonance imaging and had swallowing difficulty were included in this study. Location of the stroke was classified into three groups: territorial anterior infarcts (TAI) (n = 62), territorial posterior infarcts (TPI) (n = 19) and white matter disease (WMD) (n = 22). Oral cavity residue existed significantly in the TAI group more than in any other groups (P = 0.017). The WMD group showed more residue in the valleculae (P = 0.002) and the TPI group showed more residue in the pyriform sinuses (P = 0.001). The oral transit time, pharyngeal delay time and pharyngeal transit time did not show significant differences among the groups with swallowing of both thick and thin liquids. Penetration and aspiration were more frequent in the TPI group (P < 0.05) with swallowing of both thick and thin liquids. The results suggest that TAI is more related to oral phase dysfunction and TPI is more related to pharyngeal dysfunction. In ischemic stroke, patterns of swallowing difficulty may differ according to the vascular territory involved and this should be considered in the management of post-stroke dysphagia.


Assuntos
Transtornos de Deglutição/fisiopatologia , Deglutição/fisiologia , Fluoroscopia/métodos , Faringe/fisiopatologia , Gravação em Vídeo , Adulto , Idoso , Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/fisiopatologia
7.
Dysphagia ; 29(5): 603-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25012700

RESUMO

Chin tuck has been has been widely used to prevent aspiration in the patients with dysphagia. This study was performed to investigate the effectiveness and the degree of optimal neck flexion of chin tuck. Ninety-seven patients who showed aspiration in the videofluoroscopic swallow study (VFSS). Participants were grouped into the effective (patients who showed effect with chin tuck) and ineffective group (those who did not show effect with chin tuck). VFSS was performed in neutral and chin tuck position and findings were compared between the groups. Severity of aspiration was assessed by the point penetration-aspiration scale. Duration of dysphagic symptoms, history of tracheostomy, and other possible contributing factors were also compared. Neck flexion angle was measured to find appropriate posture in which aspiration was prevented with chin tuck. Aspiration was reduced or eliminated in only 19 patients (19.6 %) with chin tuck. Oral transit time, pharyngeal delayed time and pharyngeal transit time were significantly shortened in both groups (p < 0.05), but the difference between the groups was not significant. Female sex and absence of residue in pyriform sinus favored the effect of chin tuck (p < 0.05). At least 17.5° of neck flexion was required to achieve an effect with chin tuck. The effectiveness of chin tuck was less than anticipated. Patients without residue in pyriform sinus were more likely to benefit from chin tuck. Sufficient neck flexion was important in chin tuck to prevent aspiration.


Assuntos
Queixo/anatomia & histologia , Aspiração Respiratória/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Vértebras Cervicais/anatomia & histologia , Cinerradiografia/métodos , Deglutição/fisiologia , Transtornos de Deglutição/fisiopatologia , Feminino , Fluoroscopia/métodos , Humanos , Laringe/fisiopatologia , Lábio/fisiopatologia , Masculino , Pessoa de Meia-Idade , Boca/fisiopatologia , Pescoço/anatomia & histologia , Faringe/fisiopatologia , Postura/fisiologia , Seio Piriforme/fisiopatologia , Curva ROC , Aspiração Respiratória/diagnóstico por imagem , Sensibilidade e Especificidade , Fatores de Tempo
8.
Acta Biomater ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38871200

RESUMO

Spinal cord injury (SCI) is associated with substantial healthcare challenges, frequently resulting in enduring sensory and motor deficits alongside various chronic complications. While advanced regenerative therapies have shown promise in preclinical research, their translation into clinical application has been limited. In response, this study utilized a comprehensive network meta-analysis to evaluate the effectiveness of neural stem/progenitor cell (NSPC) transplantation across animal models of SCI. We analyzed 363 outcomes from 55 distinct studies, categorizing the treatments into NSPCs alone (cell only), NSPCs with scaffolds (cell + scaffold), NSPCs with hydrogels (cell + hydrogel), standalone scaffolds (scaffold), standalone hydrogels (hydrogel), and control groups. Our analysis demonstrated significant enhancements in motor recovery, especially in gait function, within the NSPC treatment groups. Notably, the cell only group showed considerable improvements (standardized mean difference [SMD], 2.05; 95 % credible interval [CrI]: 1.08 to 3.10, p < 0.01), as did the cell + scaffold group (SMD, 3.73; 95 % CrI: 2.26 to 5.22, p < 0.001) and the cell + hydrogel group (SMD, 3.37; 95 % CrI: 1.02 to 5.78, p < 0.05) compared to controls. These therapeutic combinations not only reduced lesion cavity size but also enhanced neuronal regeneration, outperforming the cell only treatments. By integrating NSPCs with supportive biomaterials, our findings pave the way for refining these regenerative strategies to optimize their potential in clinical SCI treatment. Although there is no overall violation of consistency, the comparison of effect sizes between individual treatments should be interpreted in light of the inconsistency. STATEMENT OF SIGNIFICANCE: This study presents a comprehensive network meta-analysis exploring the efficacy of neural stem cell (NSC) transplantation, with and without biomaterials, in animal models of spinal cord injury (SCI). We demonstrate that NSCs, particularly when combined with biomaterials like scaffolds or hydrogels, significantly enhance motor and histological recovery post-SCI. These findings underscore the potential of NSC-based therapies, augmented with biomaterials, to advance SCI treatment, offering new insights into regenerative strategies that could significantly impact clinical practices.

9.
J Clin Med ; 13(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38398304

RESUMO

(1) Background: Pressure ulcers (PUs) substantially impact the quality of life of spinal cord injury (SCI) patients and require prompt intervention. This study used machine learning (ML) techniques to develop advanced predictive models for the occurrence of PUs in patients with SCI. (2) Methods: By analyzing the medical records of 539 patients with SCI, we observed a 35% incidence of PUs during hospitalization. Our analysis included 139 variables, including baseline characteristics, neurological status (International Standards for Neurological Classification of Spinal Cord Injury [ISNCSCI]), functional ability (Korean version of the Modified Barthel Index [K-MBI] and Functional Independence Measure [FIM]), and laboratory data. We used a variety of ML methods-a graph neural network (GNN), a deep neural network (DNN), a linear support vector machine (SVM_linear), a support vector machine with radial basis function kernel (SVM_RBF), K-nearest neighbors (KNN), a random forest (RF), and logistic regression (LR)-focusing on an integrative analysis of laboratory, neurological, and functional data. (3) Results: The SVM_linear algorithm using these composite data showed superior predictive ability (area under the receiver operating characteristic curve (AUC) = 0.904, accuracy = 0.944), as demonstrated by a 5-fold cross-validation. The critical discriminators of PU development were identified based on limb functional status and laboratory markers of inflammation. External validation highlighted the challenges of model generalization and provided a direction for future research. (4) Conclusions: Our study highlights the importance of a comprehensive, multidimensional data approach for the effective prediction of PUs in patients with SCI, especially in the acute and subacute phases. The proposed ML models show potential for the early detection and prevention of PUs, thus contributing substantially to improving patient care in clinical settings.

10.
Adv Sci (Weinh) ; 10(24): e2302632, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37340589

RESUMO

Regeneration of over 10 mm long peripheral nerve defects remains a challenge due to the failure of regeneration by prolonged axotomy and denervation occurring in long-term recovery. Recent studies reveal that conductive conduits and electrical stimulation accelerate the regeneration of long nerve defects. In this study, an electroceutical platform combining a fully biodegradable conductive nerve conduit and a wireless electrical stimulator is proposed to maximize the therapeutic effect on nerve regeneration. Fully biodegradable nerve conduit fabricated using molybdenum (Mo) microparticles and polycaprolactone (PCL) can eliminate the unwanted effects of non-degradable implants, which occupy nerve paths and need to be removed through surgery increasing the risk of complications. The electrical and mechanical properties of Mo/PCL conduits are optimized by controlling the amounts of Mo and tetraglycol lubricant. The dissolution behavior and electrical conductivity of biodegradable nerve conduits in the biomimetic solutions are also evaluated. In in vivo experiments, the integrated strategy of a conductive Mo/PCL conduit with controlled therapeutic electrical stimulation shows accelerated axon regeneration for long sciatic nerve defects in rats compared to the use of the Mo/PCL conduit without stimulation and has a significant therapeutic effect based on the results obtained from the functional recovery test.


Assuntos
Axônios , Regeneração Nervosa , Ratos , Animais , Regeneração Nervosa/fisiologia , Próteses e Implantes , Nervo Isquiático/fisiologia , Condutividade Elétrica
11.
Adv Healthc Mater ; 12(7): e2201720, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36447307

RESUMO

Neural stem cells (NSC) have tremendous potential for therapeutic regeneration of diseased or traumatized neural tissues, including injured spinal cord. However, transplanted NSC suffer from low cell survival and uncontrolled differentiation, limiting in vivo efficacy. Here, this issue is tackled by delivery through silk-collagen protein hydrogels that are stiffness-matched, stress-relaxing, and shear-thinning. The mechanically-tuned hydrogels protect NSC reprogrammed from fibroblasts (iNSC) initially from injection shear-stress, and enhance long-term survival over 12 weeks. Hydrogel-iNSC treatment alleviates neural inflammation, with reduced inflammatory cells and lesions than NSC-only. The iNSC migrate from the hydrogel into surrounding tissues, secrete up-regulated neurotrophic factors, and differentiate into neural cell subtypes, forming synapses. More serotonergic axons are observed in the lesion cavity, and locomotor functions are improved in hydrogel-iNSC than in iNSC-only. This study highlights the ability of mechanically-tuned protein hydrogels to protect iNSC from the injection stress and severe inflammatory environment, allowing them to differentiate and function to recover the injured spinal cord.


Assuntos
Células-Tronco Neurais , Traumatismos da Medula Espinal , Ratos , Animais , Traumatismos da Medula Espinal/terapia , Traumatismos da Medula Espinal/patologia , Hidrogéis/farmacologia , Hidrogéis/metabolismo , Seda/metabolismo , Medula Espinal/patologia , Colágeno/metabolismo , Recuperação de Função Fisiológica
12.
J Neurosci ; 31(12): 4569-82, 2011 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-21430157

RESUMO

Dorsal root (DR) axons regenerate in the PNS but turn around or stop at the dorsal root entry zone (DREZ), the entrance into the CNS. Earlier studies that relied on conventional tracing techniques or postmortem analyses attributed the regeneration failure to growth inhibitors and lack of intrinsic growth potential. Here, we report the first in vivo imaging study of DR regeneration. Fluorescently labeled, large-diameter DR axons in thy1-YFPH mice elongated through a DR crush site, but not a transection site, and grew along the root at >1.5 mm/d with little variability. Surprisingly, they rarely turned around at the DREZ upon encountering astrocytes, but penetrated deeper into the CNS territory, where they rapidly stalled and then remained completely immobile or stable, even after conditioning lesions that enhanced growth along the root. Stalled axon tips and adjacent shafts were intensely immunolabeled with synapse markers. Ultrastructural analysis targeted to the DREZ enriched with recently arrived axons additionally revealed abundant axonal profiles exhibiting presynaptic features such as synaptic vesicles aggregated at active zones, but not postsynaptic features. These data suggest that axons are neither repelled nor continuously inhibited at the DREZ by growth-inhibitory molecules but are rapidly stabilized as they invade the CNS territory of the DREZ, forming presynaptic terminal endings on non-neuronal cells. Our work introduces a new experimental paradigm to the investigation of DR regeneration and may help to induce significant regeneration after spinal root injuries.


Assuntos
Axônios/fisiologia , Sistema Nervoso Central/fisiologia , Regeneração Nervosa/fisiologia , Sistema Nervoso Periférico/fisiologia , Receptores Pré-Sinápticos/fisiologia , Raízes Nervosas Espinhais/fisiologia , Animais , Astrócitos/fisiologia , Axônios/ultraestrutura , Diferenciação Celular/fisiologia , Sistema Nervoso Central/ultraestrutura , Feminino , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica , Compressão Nervosa , Terminações Nervosas/fisiologia , Proteínas de Neurofilamentos/metabolismo , Sistema Nervoso Periférico/ultraestrutura , Raízes Nervosas Espinhais/citologia , Raízes Nervosas Espinhais/ultraestrutura
13.
Cells ; 11(14)2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35883679

RESUMO

Gene expression changes following spinal cord injury (SCI) are time-dependent, and an accurate understanding of these changes can be crucial in determining time-based treatment options in a clinical setting. We performed RNA sequencing of the contused spinal cord of rats at five different time points from the very acute to chronic stages (1 hour, 1 day, 1 week, 1 month, and 3 months) following SCI. We identified differentially expressed genes (DEGs) and Gene Ontology (GO) terms at each time point, and 14,257 genes were commonly expressed at all time points. The biological process of the inflammatory response was increased at 1 hour and 1 day, and the cellular component of the integral component of the synaptic membrane was increased at 1 day. DEGs associated with cell activation and the innate immune response were highly enriched at 1 week and 1 month, respectively. A total of 2841 DEGs were differentially expressed at any of the five time points, and 18 genes (17 upregulated and 1 downregulated) showed common expression differences at all time points. We found that interleukin signaling, neutrophil degranulation, eukaryotic translation, collagen degradation, LGI-ADAM interactions, GABA receptor, and L1CAM-ankyrin interactions were prominent after SCI depending on the time post injury. We also performed gene-drug network analysis and found several potential antagonists and agonists which can be used to treat SCI. We expect to discover effective treatments in the clinical field through further studies revealing the efficacy and safety of potential drugs.


Assuntos
Perfilação da Expressão Gênica , Traumatismos da Medula Espinal , Animais , Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Ratos , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo
14.
Ann Rehabil Med ; 46(4): 172-184, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36070999

RESUMO

OBJECTIVE: To investigate the clinical usefulness of diffusion tensor imaging (DTI) and tractography in the prediction of outcomes after traumatic cervical spinal cord injury (SCI) and to assess whether the predictability is different between DTI and tractography administered before and after surgery. METHODS: Sixty-one subjects with traumatic cervical SCI were randomly assigned to preop or postop groups and received DTI accordingly. Among the patients who had DTI before surgery, we assigned 10 patients who had received repeated DTI examinations at 8 weeks after injury to the follow-up group. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained from DTI, and imaginary fiber and crossing fiber numbers were calculated from the tractography. Neurological status and functional status were assessed at 4 and 8 weeks after SCI. RESULTS: The neurologic and functional statuses of both groups improved after 4 weeks. Out of the initial 61 patients who were enrolled in the study, the failure rate of DTI image analysis was significantly higher in the postop group (n=17, 41.5%) than in the preop group (n=6, 20%). The FA values and fiber numbers in the preop group tended to be higher than those in the postop group, whereas ADC values were lower in the preop group. When comparing the tractographic findings in the follow-up group, imaginary fiber numbers at the C6 and C7 levels and crossing fiber numbers from the C3 to C6 levels were significantly decreased after surgery. Several DTI and tractographic parameters (especially the ADC value at the C4 level and imaginary fiber numbers at the C6 level) showed significant correlations with neurologic and functional statuses in both the preop and postop groups. These findings were most prominent when DTI and physical examination were simultaneously performed. CONCLUSION: Preoperative DTI and tractography demonstrated better FA and ADC values with lower interpretation failure rates than those obtained after surgery, whereas postoperative data significantly reflected the patient's clinical state at the time of evaluation. Therefore, DTI and tractography could be useful in predicting clinical outcomes after traumatic cervical SCI and should be interpreted separately before and after spine surgery.

15.
J Clin Med ; 11(8)2022 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-35456358

RESUMO

Poststroke depression (PSD) is a major psychiatric disorder that develops after stroke; however, whether PSD treatment improves cognitive and functional impairments is not clearly understood. We reviewed data from 31 subjects with PSD and 34 age-matched controls without PSD; all subjects underwent neurological, cognitive, and functional assessments, including the National Institutes of Health Stroke Scale (NIHSS), the Korean version of the Mini-Mental Status Examination (K-MMSE), computerized neurocognitive test (CNT), the Korean version of the Modified Barthel Index (K-MBI), and functional independence measure (FIM) at admission to the rehabilitation unit in the subacute stage following stroke and 4 weeks after initial assessments. Machine learning methods, such as support vector machine, k-nearest neighbors, random forest, voting ensemble models, and statistical analysis using logistic regression were performed. PSD was successfully predicted using a support vector machine with a radial basis function kernel function (area under curve (AUC) = 0.711, accuracy = 0.700). PSD prognoses could be predicted using a support vector machine linear algorithm (AUC = 0.830, accuracy = 0.771). The statistical method did not have a better AUC than that of machine learning algorithms. We concluded that the occurrence and prognosis of PSD in stroke patients can be predicted effectively based on patients' cognitive and functional statuses using machine learning algorithms.

16.
J Tissue Eng ; 13: 20417314221086491, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35340425

RESUMO

Spinal cord injury (SCI) leads to disruption of the blood-spinal cord barrier, hemorrhage, and tissue edema, which impair blood circulation and induce ischemia. Angiogenesis after SCI is an important step in the repair of damaged tissues, and the extent of angiogenesis strongly correlates with the neural regeneration. Various biomaterials have been developed to promote angiogenesis signaling pathways, and angiogenic self-assembling peptides are useful for producing diverse supramolecular structures with tunable functionality. RADA16 (Ac-RARADADARARADADA-NH2), which forms nanofiber networks under physiological conditions, is a self-assembling peptide that can provide mechanical support for tissue regeneration and reportedly has diverse roles in wound healing. In this study, we applied an injectable form of RADA16 with or without the neuropeptide substance P to the contused spinal cords of rats and examined angiogenesis within the damaged spinal cord and subsequent functional improvement. Histological and immunohistochemical analyses revealed that the inflammatory cell population in the lesion cavity was decreased, the vessel number and density around the damaged spinal cord were increased, and the levels of neurofilaments within the lesion cavity were increased in SCI rats that received RADA16 and RADA16 with substance P (rats in the RADA16/SP group). Moreover, real-time PCR analysis of damaged spinal cord tissues showed that IL-10 expression was increased and that locomotor function (as assessed by the Basso, Beattie, and Bresnahan (BBB) scale and the horizontal ladder test) was significantly improved in the RADA16/SP group compared to the control group. Our findings indicate that RADA16 modified with substance P effectively stimulates angiogenesis within the damaged spinal cord and is a candidate agent for promoting functional recovery post-SCI.

17.
NPJ Regen Med ; 7(1): 62, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36261427

RESUMO

Guiding the regrowth of thousands of nerve fibers within a regeneration-friendly environment enhances the regeneration capacity in the case of peripheral nerve injury (PNI) and spinal cord injury (SCI). Although clinical treatments are available and several studies have been conducted, the development of nerve guidance conduits (NGCs) with desirable properties, including controllable size, hundreds of nerve bundle-sized microchannels, and host stem-cell recruitment, remains challenging. In this study, the micropattern-based fabrication method was combined with stem-cell recruitment factor (substance P, SP) immobilization onto the main material to produce a size-tunable NGC with hundreds of microchannels with stem-cell recruitment capability. The SP-immobilized multiple microchannels aligned the regrowth of nerve fibers and recruited the host stem cells, which enhanced the functional regeneration capacity. This method has wide applicability in the modification and augmentation of NGCs, such as bifurcated morphology or directional topographies on microchannels. Additional improvements in fabrication will advance the regeneration technology and improve the treatment of PNI/SCI.

18.
J Clin Med ; 10(19)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34640594

RESUMO

Diabetic sensorimotor polyneuropathy (DSPN) is a major complication in patients with diabetes mellitus (DM), and early detection or prediction of DSPN is important for preventing or managing neuropathic pain and foot ulcer. Our aim is to delineate whether machine learning techniques are more useful than traditional statistical methods for predicting DSPN in DM patients. Four hundred seventy DM patients were classified into four groups (normal, possible, probable, and confirmed) based on clinical and electrophysiological findings of suspected DSPN. Three ML methods, XGBoost (XGB), support vector machine (SVM), and random forest (RF), and their combinations were used for analysis. RF showed the best area under the receiver operator characteristic curve (AUC, 0.8250) for differentiating between two categories-criteria by clinical findings (normal, possible, and probable groups) and those by electrophysiological findings (confirmed group)-and the result was superior to that of linear regression analysis (AUC = 0.6620). Average values of serum glucose, International Federation of Clinical Chemistry (IFCC), HbA1c, and albumin levels were identified as the four most important predictors of DSPN. In conclusion, machine learning techniques, especially RF, can predict DSPN in DM patients effectively, and electrophysiological analysis is important for identifying DSPN.

19.
Cells ; 10(1)2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33445717

RESUMO

Exercise training is a traditional method to maximize remaining function in patients with spinal cord injury (SCI), but the exact mechanism by which exercise promotes recovery after SCI has not been identified; whether exercise truly has a beneficial effect on SCI also remains unclear. Previously, we showed that epigenetic changes in the brain motor cortex occur after SCI and that a treatment leading to epigenetic modulation effectively promotes functional recovery after SCI. We aimed to determine how exercise induces functional improvement in rats subjected to SCI and whether epigenetic changes are engaged in the effects of exercise. A spinal cord contusion model was established in rats, which were then subjected to treadmill exercise for 12 weeks. We found that the size of the lesion cavity and the number of macrophages were decreased more in the exercise group than in the control group after 12 weeks of injury. Immunofluorescence and DNA dot blot analysis revealed that levels of 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC) in the brain motor cortex were increased after exercise. Accordingly, the expression of ten-eleven translocation (Tet) family members (Tet1, Tet2, and Tet3) in the brain motor cortex also elevated. However, no macrophage polarization was induced by exercise. Locomotor function, including Basso, Beattie, and Bresnahan (BBB) and ladder scores, also improved in the exercise group compared to the control group. We concluded that treadmill exercise facilitates functional recovery in rats with SCI, and mechanistically epigenetic changes in the brain motor cortex may contribute to exercise-induced improvements.


Assuntos
Metilação de DNA/genética , Condicionamento Físico Animal , Traumatismos da Medula Espinal/genética , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Animais , Axônios/patologia , Polaridade Celular , Epigênese Genética , Feminino , Hidroxilação , Inflamação/patologia , Macrófagos/patologia , Córtex Motor/metabolismo , Regeneração Nervosa , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Medula Espinal/patologia , Traumatismos da Medula Espinal/complicações , Bexiga Urinaria Neurogênica/etiologia
20.
Ann Rehabil Med ; 45(2): 99-107, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33849085

RESUMO

OBJECTIVE: To identify the variables of videofluoroscopic swallowing study (VFSS) that are useful for predicting the risk of aspiration pneumonia in elderly patients with dysphagia. METHODS: A total of 251 patients (aged 65 years or more) were included and divided into a pneumonia group (n=133) and a non-pneumonia group (n=118). The pneumonia group included patients who had been diagnosed with aspiration pneumonia, and individuals in the non-pneumonia group did not have pneumonia but were referred for VFSS. The medical records and results of VFSS were reviewed and compared between the groups retrospectively. RESULTS: The pneumonia group exhibited a male preponderance and a higher 8-point Penetration-Aspiration Scale (8PPAS) score. The mean values of 8PPAS score for swallowing thick liquid and rice porridge was significantly higher in the pneumonia group. The pharyngeal delay time (PDT) and pharyngeal transit time (PTT) were significantly longer in the pneumonia group. The amounts of vallecular and pyriform sinus residue were increased in the pneumonia group. The delay in swallowing reflex and the decrease in laryngeal elevation were more frequently observed in the pneumonia group. Among those variables, PDT and PTT were identified as significant predictors of aspiration pneumonia based on logistic regression analysis. CONCLUSION: The present study delineated the findings of VFSS, suggesting an increased risk of aspiration pneumonia in elderly patients with dysphagia. The results demonstrate that prolonged PDT and PTT are significant predictors of aspiration pneumonia.

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