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1.
Soft Matter ; 16(2): 428-434, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31799582

RESUMEN

Maturation and synchronisation of heart cells, including cardiomyocytes and fibroblasts, are essential to develop functional biomimetic cardiac tissues for regenerative medicine and drug discovery. Synchronisation of cells in the biomimetic cardiac tissue requires the structural integrity and functional maturation of cardiomyocytes with other cell types. However, it is challenging to synchronise the beating of macroscale cardiac tissues and induce maturation of cardiomyocytes derived from stem cells. Here, we developed a simple assembly technology to modulate cell-cell interactions by combining layer-by-layer (LBL) deposition and centrifugation of cells with collagen type I to control cell-cell interactions for the preparation of cardiac macro tissues (CMTs). We found that maturation of cardiomyocytes in CMTs was largely enhanced by growth factors FGF-4 and ascorbic acid, but synchronisation of cardiac beating required LBL deposition of cardiomyocytes and cardiac fibroblasts in addition to the growth factors during the maturation process. Our findings have important implications because incorporation of cardiac fibroblasts into the cardiomyocyte layer is a prerequisite for synchronised beating of macroscale cardiac tissues in addition to growth factors to facilitate maturation of stem cell-derived cardiomyocytes.


Asunto(s)
Fibroblastos/citología , Miocitos Cardíacos/citología , Materiales Biomiméticos/química , Materiales Biomiméticos/metabolismo , Biomimética , Bioimpresión , Comunicación Celular , Colágeno Tipo I/metabolismo , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Factor 4 de Crecimiento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Humanos , Miocitos Cardíacos/metabolismo
2.
Telemed J E Health ; 25(12): 1231-1236, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-30758247

RESUMEN

Background: Recently, the application of smartphone in medical field has received great attention.Introduction: The objective of this study was to compare the effectiveness of smartphone-based and conventional pedometer-based exercise monitoring systems in promoting home exercise among prostate cancer patients.Methods: Prostate cancer patients who have undergone surgery or androgen deprivation therapy were recruited. All participants were provided with physical activity goals based on their activities and were advised to achieve these goals during their home exercise period. The intervention group was instructed to use smartphone application to record their activities; they also received weekly remote consultations based on the activity record from the application, without visiting a clinic. The control group was instructed to keep a written record of their daily activities based on pedometer readings; these records were checked by clinicians during follow-up visits. The uptake, adherence, and completion rates of two groups were compared by intention-to-treat analysis. Changes in physical function during the exercise period were analyzed.Results: In total, 100 patients were recruited (smartphone: 5 and pedometer: 50). No significant differences were detected between groups in rates of uptake (80.0% vs. 88.0%, p = 0.28), adherence (92.5% vs. 79.5%, p = 0.12), or completion (76.0% vs. 86.0%, p = 0.20). Physical functions were significantly improved in both groups.Conclusions: The smartphone-based exercise monitoring system and the pedometer yielded comparable results in promoting physical activity, as assessed by rates of uptake, adherence, and completion. Exercise monitoring was effective in improving physical functions, in both methods.


Asunto(s)
Ejercicio Físico , Promoción de la Salud/métodos , Neoplasias de la Próstata/rehabilitación , Teléfono Inteligente , Dispositivos Electrónicos Vestibles , Anciano , Humanos , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Estudios Prospectivos , República de Corea
3.
Arch Phys Med Rehabil ; 99(12): 2532-2539.e1, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29981313

RESUMEN

OBJECTIVE: To investigate the clinical usefulness of the peak cough flow generated during the citric acid reflexive cough test (0.28 mol/L) by determining the appropriate cutoff values that could accurately predict aspiration pneumonia within the first 6 months after onset. DESIGN: Retrospective analysis of a prospectively maintained database. SETTING: University-affiliated hospital. PARTICIPANTS: Patients (N=163) with first-ever diagnosed dysphagia attributable to cerebrovascular disease, who had undergone the citric acid reflexive cough test on the same day they underwent the instrumental assessment of swallowing, such as videofluoroscopy or the functional endoscopic swallowing test. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Peak cough flow (L/min) from the citric acid reflexive cough test. RESULTS: A final 163 patients had full medical records with 6-month follow-up. Receiver operating curve analysis showed that peak cough flow cutoff values set at 59 L/min were significantly associated with aspiration pneumonia (area under the curve [AUC] 95% confidence interval =0.88 [0.83-0.93]). This cutoff value significantly (P<.001) predicted the risk of aspiration pneumonia with an odds ratio of 21.56 (9.62-48.28). A multivariate regression logistic regression analysis model including initial dysphagia severity, low body mass index, and decreased level of cognition showed that inclusion of the peak cough flow from the citric acid reflexive cough test significantly improved the predictive model of aspiration pneumonia within the first 6 months after onset (AUC=0.91 vs 0.79). CONCLUSIONS: Those with reflexive cough strength less than 59 L/min may be at high risk of respiratory infections within the first 6 months after dysphagia onset. Objective measurement of reflexive cough strength may help to predict those at risk of aspiration pneumonia.


Asunto(s)
Tos/diagnóstico , Trastornos de Deglución/fisiopatología , Neumonía por Aspiración/diagnóstico , Pruebas de Función Respiratoria/estadística & datos numéricos , Medición de Riesgo/métodos , Anciano , Área Bajo la Curva , Ácido Cítrico , Bases de Datos Factuales , Trastornos de Deglución/complicaciones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Ápice del Flujo Espiratorio , Neumonía por Aspiración/etiología , Valor Predictivo de las Pruebas , Estudios Prospectivos , Valores de Referencia , Pruebas de Función Respiratoria/métodos , Estudios Retrospectivos
4.
Acta Neurochir (Wien) ; 159(6): 1005-1011, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28421284

RESUMEN

The association and mechanism involved in swallowing disturbance and normal pressure hydrocephalus (NPH) needs to be established. We report a case report where a patient who showed progressive swallowing dysfunction was diagnosed with secondary NPH. Tractography analysis showed corticobulbar tract compression by ventricular dilation. Drainage operation led to the recovery of tract volume with an improvement of swallowing function. We also report ten case series in which secondary NPH was associated with a swallowing disturbance. In these cases, dysphagia also showed improvement after shunt operation. We review the literature regarding the corticobulbar tract and its association with swallowing disturbance and the possible underlying pathophysiological mechanism in secondary NPH. This report highlights that swallowing disturbance may manifest in those with secondary NPH due to corticobulbar tract involvement. Our findings suggest that involvement of the corticobulbar tract may be a possible cause of dysphagia in secondary NPH that may be reversible after shunt operation.


Asunto(s)
Trastornos de Deglución/etiología , Hidrocéfalo Normotenso/cirugía , Complicaciones Posoperatorias/etiología , Derivación Ventriculoperitoneal/efectos adversos , Anciano , Trastornos de Deglución/diagnóstico por imagen , Imagen de Difusión Tensora , Femenino , Humanos , Hidrocéfalo Normotenso/diagnóstico , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/diagnóstico por imagen , Tractos Piramidales/patología
5.
Clin Hypertens ; 29(1): 15, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37259165

RESUMEN

BACKGROUND: Cuffless blood pressure (BP) measurement, enabled by recent advances in wearable devices, allows for BP monitoring in daily life. This study aims to evaluate the feasibility, cresdence, and usefulness of cuffless BP monitoring through a population survey. METHODS: During the "Daily BP Measurement with Your Galaxy Watch" campaign held by the Korean Society of Hypertension, participants were asked to share their experiences with cuffless BP measurement using a smartwatch application through an online survey. The questionnaire included questions about age, underlying medical conditions, smartwatch utilization, experience with BP calibration, the reliability of BP values measured by a smartwatch, and willingness to use the BP monitoring function in the future. RESULTS: A total of 1071 participants responded to the survey. The largest age group (decile) was 50-59 years old (33.3%), followed by 40-49 years old (29.9%). Although nearly half of the participants (47.5%) had no chronic diseases, 40.1% reported having hypertension. BP monitoring was the most frequently utilized smartwatch function (95.8%), followed by heart rate measurement (87.1%). 31.8% of participants reported that BP values measured by the smartphone application were "very accurate and helpful," while 63.5% rated them as "slightly lower (44.4%)" or "higher (19.1%)" compared to the standard home BP monitoring device. 93% of the participants reported utilizing the BP monitoring function at least once a week. Regarding the BP calibration process, most participants (93.9%) calibrated the BP measurement application themselves, and 50.8% rated the difficulty level as "very easy." CONCLUSION: Cuffless BP measurement using a smartwatch application was feasible in the general population, including the self-calibration process. However, the satisfaction level in terms of accuracy is still modest, indicating a need for further development.

6.
Biomed Opt Express ; 14(2): 577-592, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36874497

RESUMEN

Biomedical researchers use optical coherence microscopy (OCM) for its high resolution in real-time label-free tomographic imaging. However, OCM lacks bioactivity-related functional contrast. We developed an OCM system that can measure changes in intracellular motility (indicating cellular process states) via pixel-wise calculations of intensity fluctuations from metabolic activity of intracellular components. To reduce image noise, the source spectrum is split into five using Gaussian windows with 50% of the full bandwidth. The technique verified that F-actin fiber inhibition by Y-27632 reduces intracellular motility. This finding could be used to search for other intracellular-motility-associated therapeutic strategies for cardiovascular diseases.

7.
Nat Commun ; 14(1): 6256, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37802991

RESUMEN

Soot generation is a major challenge in industries. The elimination of soot is particularly crucial to reduce pollutant emissions and boost carbon conversion. The mechanisms for soot oxidation are complex, with quantified models obtained under in situ conditions still missing. We prepare soot samples via noncatalytic partial oxidation of methane. Various oxidation models are established based on the results of in situ transmission electron microscopy experiments. A quantified maturity parameter is proposed and used to categorize the soot particles according to the nanostructure at various maturity levels, which in turn lead to different oxidation mechanisms. To tackle the challenges in the kinetic analysis of soot aggregates, a simplification model is proposed and soot oxidation rates are quantified. In addition, a special core-shell separation model is revealed through in situ analysis and kinetic studies. In this study, we obtain important quantified models for soot oxidation under in situ conditions.

8.
Cells ; 12(16)2023 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-37626839

RESUMEN

The generation of mature and vascularized human pluripotent stem cell-derived cardiac organoids (hPSC-COs) is necessary to ensure the validity of drug screening and disease modeling. This study investigates the effects of cellular aggregate (CA) stemness and self-organization on the generation of mature and vascularized hPSC-COs and elucidates the mechanisms underlying cardiac organoid (CO) maturation and vascularization. COs derived from 2-day-old CAs with high stemness (H-COs) and COs derived from 5-day-old CAs with low stemness (L-COs) were generated in a self-organized microenvironment via Wnt signaling induction. This study finds that H-COs exhibit ventricular, structural, metabolic, and functional cardiomyocyte maturation and vessel networks consisting of endothelial cells, smooth muscle cells, pericytes, and basement membranes compared to L-COs. Transcriptional profiling shows the upregulation of genes associated with cardiac maturation and vessel formation in H-COs compared with the genes in L-COs. Through experiments with LIMK inhibitors, the activation of ROCK-LIMK-pCofilin via ECM-integrin interactions leads to cardiomyocyte maturation and vessel formation in H-COs. Furthermore, the LIMK/Cofilin signaling pathway induces TGFß/NODAL and PDGF pathway activation for the maturation and vascularization of H-COs. The study demonstrates for the first time that LIMK/Cofilin axis activation plays an important role in the generation of mature and vascularized COs.


Asunto(s)
Células Endoteliales , Organoides , Humanos , Miocitos Cardíacos , Vía de Señalización Wnt , Factores Despolimerizantes de la Actina , Matriz Extracelular , Neovascularización Patológica , Integrinas
9.
Tissue Eng Regen Med ; 19(4): 781-792, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35258794

RESUMEN

BACKGROUND: During cardiogenesis, cardiac cells receive various stimuli, such as biomechanical and chemical cues, from the surrounding microenvironment, and these signals induce the maturation of heart cells. Mechanical force, especially tensile force in the heart, is one of the key stimuli that induce cardiomyocyte (CM) maturation through mechanotransduction, a process through which physical cues are transformed into biological responses. However, the effects and mechanisms of tensile force on cell maturation are poorly studied. METHODS: In this study, we developed a cyclic stretch system that mimics the mechanical environment of the heart by loading tensile force to human-induced pluripotent stem cell (hiPSC)-derived CMs. hiPSC-CMs cultured with the cyclic stretch system analyzed morphological change, immunofluorescent staining, expression of maturation markers in mRNA, and beating properties compared to static cultures. RESULTS: hiPSC-CMs cultured with the cyclic stretch system showed increased cell alignment, sarcomere length and expression of maturation markers in mRNA, such as TNNI3, MYL2 and TTN, compared to static cultures. Especially, the expression of genes related to nuclear mechanotransduction, such as Yap1, Lamin A/C, plectin, and desmin, was increased in the cyclically stretched hiPSC-CMs. Furthermore, the volume of the nucleus was increased by as much as 120% in the cyclic stretch group. CONCLUSION: These results revealed that nuclear mechanotransduction induced by tensile force is involved in CM maturation. Together, these findings provide novel evidence suggesting that nuclear mechanotransduction induced by tensile force is involved in the regulation of cardiac maturation.


Asunto(s)
Células Madre Pluripotentes Inducidas , Diferenciación Celular , Humanos , Mecanotransducción Celular , Miocitos Cardíacos , ARN Mensajero/genética , ARN Mensajero/metabolismo
10.
Micromachines (Basel) ; 12(4)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33916254

RESUMEN

Cardiac tissue engineering aims to generate in vivo-like functional tissue for the study of cardiac development, homeostasis, and regeneration. Since the heart is composed of various types of cells and extracellular matrix with a specific microenvironment, the fabrication of cardiac tissue in vitro requires integrating technologies of cardiac cells, biomaterials, fabrication, and computational modeling to model the complexity of heart tissue. Here, we review the recent progress of engineering techniques from simple to complex for fabricating matured cardiac tissue in vitro. Advancements in cardiomyocytes, extracellular matrix, geometry, and computational modeling will be discussed based on a technology perspective and their use for preparation of functional cardiac tissue. Since the heart is a very complex system at multiscale levels, an understanding of each technique and their interactions would be highly beneficial to the development of a fully functional heart in cardiac tissue engineering.

11.
Cells ; 10(10)2021 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-34685725

RESUMEN

Mature cardiomyocytes (CMs) obtained from human pluripotent stem cells (hPSCs) have been required for more accurate in vitro modeling of adult-onset cardiac disease and drug discovery. Here, we found that FGF4 and ascorbic acid (AA) induce differentiation of BG01 human embryonic stem cell-cardiogenic mesoderm cells (hESC-CMCs) into mature and ventricular CMs. Co-treatment of BG01 hESC-CMCs with FGF4+AA synergistically induced differentiation into mature and ventricular CMs. FGF4+AA-treated BG01 hESC-CMs robustly released acute myocardial infarction (AMI) biomarkers (cTnI, CK-MB, and myoglobin) into culture medium in response to hypoxic injury. Hypoxia-responsive genes and potential cardiac biomarkers proved in the diagnosis and prognosis of coronary artery diseases were induced in FGF4+AA-treated BG01 hESC-CMs in response to hypoxia based on transcriptome analyses. This study demonstrates that it is feasible to model hypoxic stress in vitro using hESC-CMs matured by soluble factors.


Asunto(s)
Ácido Ascórbico/farmacología , Diferenciación Celular , Factor 4 de Crecimiento de Fibroblastos/farmacología , Células Madre Embrionarias Humanas/patología , Modelos Biológicos , Miocitos Cardíacos/patología , Estrés Fisiológico , Biomarcadores/metabolismo , Diferenciación Celular/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Línea Celular , Medios de Cultivo/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Ventrículos Cardíacos/patología , Células Madre Embrionarias Humanas/efectos de los fármacos , Humanos , Infarto del Miocardio/patología , Miocitos Cardíacos/efectos de los fármacos , Estrés Fisiológico/efectos de los fármacos , Transcriptoma/genética
12.
Biomaterials ; 278: 121133, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34571434

RESUMEN

The generation of mature ventricular cardiomyocytes (CMs) resembling adult CMs from human pluripotent stem cells (hPSCs) is necessary for disease modeling and drug discovery. To investigate the effect of self-organizing capacity on the generation of mature cardiac organoids (COs), we generated cardiac mesoderm cell-derived COs (CMC-COs) and CM-derived COs (CM-COs) and evaluated COs. CMC-COs exhibited more organized sarcomere structures and mitochondria, well-arranged t-tubule structures, and evenly distributed intercalated discs. Increased expressions of ventricular CM, cardiac metabolic, t-tubule formation, K+ ion channel, and junctional markers were confirmed in CMC-COs. Mature ventricular-like function such as faster motion vector speed, decreased beats per min, increased peak-to-peak duration, and prolonged APD50 and APD90 were observed in CMC-COs. Transcriptional profiling revealed that extracellular matrix-integrin, focal adhesion, and LEFTY-PITX2 signaling pathways are upregulated in CMC-COs. LEFTY knockdown affected ECM-integrin-FA signaling pathways in CMC-COs. Here, we found that high self-organizing capacity of CMCs is critical for the generation of mature and ventricular COs. We also demonstrated that LEFTY-PITX2 signaling plays key roles for CM maturation and specification into ventricular-like CM subtype in CMC-COs. CMC-COs are an attractive resource for disease modeling and drug discovery.


Asunto(s)
Proteínas de Homeodominio , Células Madre Pluripotentes Inducidas , Factores de Determinación Derecha-Izquierda , Miocitos Cardíacos , Células Madre Pluripotentes , Factores de Transcripción , Diferenciación Celular , Proteínas de Homeodominio/metabolismo , Humanos , Factores de Determinación Derecha-Izquierda/metabolismo , Mesodermo , Organoides , Transducción de Señal , Factores de Transcripción/metabolismo , Proteína del Homeodomínio PITX2
13.
Brain Neurorehabil ; 13(3): e20, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36741793

RESUMEN

Hemispatial neglect is a symptom where patients do not show response to stimuli on the contralesional side of their brain lesion. Although it is most common in the context of hemispheric stroke, several pathological processes including neurodegenerative disease, neoplasia, and trauma may cause this. Prevalence of hemispatial neglect is unknown and rarely reported among patients with hypoxic brain injury. Also, hemispatial neglect accompanying neglect dyslexia is rather hard to be recognized and symptoms involving numbers are exceptionally rare. We report a patient with hypoxic brain injury following cardiac arrest who showed signs of neglect dyslexia for numbers that provided a primary clue for the diagnosis of left hemispatial neglect. Early detection of different forms of cognitive dysfunction of hypoxic brain injury is highly essential in providing early neurorehabilitation for better prognosis.

14.
J Clin Neurosci ; 71: 113-118, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31495657

RESUMEN

This study investigated the association between the presence of sarcopenia, measured by nonhemiplegic grip strength, and the level of functional recovery, measured by the modified Rankin Scale (mRS) at six months after stroke. We performed a retrospective cohort analysis of a prospectively maintained database of 194 hemiplegic poststroke patients, who had been admitted to the Department of Rehabilitation Medicine of a university-affiliated hospital. At 6 months after stroke, 72.2% of patients had mRS score >3, with more women (81.0% vs. 66.0%, p = 0.024) showing poor recovery. Both men (51.3% vs. 35.9%, p = 0.041) and women (42.2% vs. 6.7%, p = 0.022) with mRS score >3 had a higher rate of sarcopenia. Univariate analysis revealed that the presence of sarcopenia was associated with a 2.71-fold higher risk of poor recovery at six months. In addition, women had a 2.18-fold higher risk of poor outcome. Multivariable logistic regression analysis revealed that the presence of sarcopenia was associated with poor functional outcome (odds ratio [OR] = 2.61, 95% confidence interval [CI]: 1.14-5.98, p = 0.024) in men, but this association was notably stronger in women (OR = 9.93, 95% CI: 1.22-81.19, p = 0.032). This study suggests that the presence of sarcopenia two weeks after stroke may increase the risk of poor functional outcome six months after stroke. Most notably, women with sarcopenia within 2 weeks from stroke onset were more significantly likely to have a poor modified Rankin Scale after 6 months.


Asunto(s)
Recuperación de la Función/fisiología , Sarcopenia/fisiopatología , Accidente Cerebrovascular/fisiopatología , Resultado del Tratamiento , Anciano , Estudios de Cohortes , Femenino , Fuerza de la Mano , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Análisis de Regresión , Estudios Retrospectivos , Factores Sexuales
15.
Am J Phys Med Rehabil ; 99(5): 409-419, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31764223

RESUMEN

OBJECTIVE: The aim of the study was to compare the effects of hydrotherapy and land-based conventional therapy on postural balance and knee strength in stroke patients. DESIGNS: A comprehensive search was done via databases (PubMed, EMBASE, and Web of Science) until April 12, 2019, to select randomized controlled trials. The methodological quality was assessed by the PEDro scale. Berg Balance Scale was pooled as the primary outcome and Forward Reach Test, Timed Up and Go test, and paretic knee flexor and knee extensor torque as secondary outcomes. RESULTS: Eleven articles were included. Pooled results showed that hydrotherapy was more beneficial in stroke patients on Berg Balance Scale (mean difference = 1.60, 95% confidence interval = 1.00 to 2.19), Forward Reach Test (mean difference = 1.78, 95% confidence interval = 0.73 to 2.83), Timed Up and Go test (mean difference = -1.41, 95% confidence interval: -2.44 to 0.42), and knee extensor torque (mean difference = 6.14, 95% confidence interval = 0.59 to 11.70) than conventional therapy. In subgroup analysis according to stroke-onset duration, hydrotherapy for chronic stroke patients exhibited significant effectiveness on Berg Balance Scale (mean difference = 1.61, 95% confidence interval = 1.00-.21); no significant effect was observed in subacute stroke patients (mean difference = 1.04, 95% confidence interval = -2.62 to 4.70). CONCLUSION: Stroke patients showed improvement in postural balance and paretic knee extensor strength with hydrotherapy. Hydrotherapy exhibited significant effects on improving postural balance in chronic patients than in subacute patients.


Asunto(s)
Hidroterapia/métodos , Articulación de la Rodilla/fisiopatología , Parálisis/fisiopatología , Parálisis/rehabilitación , Equilibrio Postural , Rehabilitación de Accidente Cerebrovascular/métodos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto
16.
RSC Adv ; 10(36): 21328, 2020 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35532503

RESUMEN

[This corrects the article DOI: 10.1039/D0RA01577F.].

17.
RSC Adv ; 10(32): 18806-18815, 2020 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-35693693

RESUMEN

The fabrication of biomimetic structures for tissues and organs is emerging in the fields of biomedical engineering and precision medicine. While current progress in biomedical research provides a number of biofabrication methods, the construction of multi-dimensional cardiac tissue is highly challenging due to difficulties in the maturation and synchronization of cardiomyocytes (CMs) in conjunction with other types of cells, such as myofibroblasts and endothelial cells. Here, we show a simple fabrication methodology to construct multi-dimensional cardiac macro tissue (mCMT) by layer-by-layer (LBL) deposition of cells on micro patterned PDMS. mCMTs formed by LBL deposition of pluripotent stem cell (PSC)-derived cardiomyocytes and cardiac fibroblasts formed 3D patterned structures with synchronized beating characteristics. We also demonstrate that cardiac maturation factors such as the gene expression of MLC2v and cTNI and formation of sarcomeres in mCMTs were significantly enhanced by LBL deposition and growth factors during the maturation process. Fabrication of matured mCMTs with synchronized beating enables providing an efficient platform for evaluating the efficacy and toxicity of drug candidates. These results have important implications because mCMTs are applicable to diverse in vitro studies and drug screening methods that require tissue-like structures and functions in a physiological environment.

18.
Polymers (Basel) ; 11(4)2019 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-30995718

RESUMEN

In vitro maturation of cardiomyocytes in 3D is essential for the development of viable cardiac models for therapeutic and developmental studies. The method by which cardiomyocytes undergoes maturation has significant implications for understanding cardiomyocytes biology. The regulation of the extracellular matrix (ECM) by changing the composition and stiffness is quintessential for engineering a suitable environment for cardiomyocytes maturation. In this paper, we demonstrate that collagen type I, a component of the ECM, plays a crucial role in the maturation of cardiomyocytes. To this end, embryonic stem-cell derived cardiomyocytes were incorporated into Matrigel-based hydrogels with varying collagen type I concentrations of 0 mg, 3 mg, and 6 mg. Each hydrogel was analyzed by measuring the degree of stiffness, the expression levels of MLC2v, TBX18, and pre-miR-21, and the size of the hydrogels. It was shown that among the hydrogel variants, the Matrigel-based hydrogel with 3 mg of collagen type I facilitates cardiomyocyte maturation by increasing MLC2v expression. The treatment of transforming growth factor ß1 (TGF-ß1) or fibroblast growth factor 4 (FGF-4) on the hydrogels further enhanced the MLC2v expression and thereby cardiomyocyte maturation.

19.
Prim Health Care Res Dev ; 20: e70, 2018 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-30375303

RESUMEN

AIM: To analyze the use of YouTube videos as educational tools for four physical examinations of the shoulder: the Neer, Hawkins, empty can, and drop arm tests. BACKGROUND: Video-based education, which is accompanied by text-based education, can be an effective education method, especially in learning medical skills. Medical students and doctors in training often use YouTube videos to share medical education materials, and more systematic review of the reliability of these videos is required. METHODS: A search of YouTube was conducted using four keywords: 'Neer test,' 'Hawkins test,' 'empty can test,' and 'drop arm test.' Two physicians reviewed each video and recorded a variety of characteristics (date uploaded, number of views, likes and dislikes, and upload source). In addition, they scored and categorized the videos into four groups: 'very useful,' 'somewhat useful,' 'not useful,' and 'misleading.' Videos containing inappropriate content were classified as 'misleading.' Finally, the correlations of each video's usefulness with viewers' preferences and the upload source were analyzed. RESULTS: A total of 400 videos were assessed and 200 videos were adopted which yield eligible criteria. Out of 200 videos, 51 videos were very useful and 32 were misleading. Significant correlations were observed between the video's usefulness and the uploaded source, as well as between the video's usefulness and viewers' preferences, such as the number of views, views per day, and number of likes. The proportion of videos classified as 'very useful' was highest (58.6%) among those uploaded by physicians and lowest (12.7%) among those uploaded by individuals. Videos uploaded by individuals had significantly lower values reflecting viewer preferences than did videos uploaded by physicians. CONCLUSION: YouTube videos could be used as learning sources for shoulder physical examinations after the application of appropriate filtering processes, such as review of the upload source and viewers' preferences.

20.
PM R ; 10(8): 789-797, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29510234

RESUMEN

BACKGROUND: There are no guidelines on the ideal time to inject botulinum toxin type A (BT-A) for lower leg spasticity in stroke patients. An early injection may produce unwanted weakness, interfering with gait recovery. OBJECTIVE: To evaluate whether the outcomes after BT-A injection for plantarflexion spasticity can be different according to stroke chronicity. DESIGN: A secondary analysis study from a double-blinded, randomized trial with group reclassification according to stroke chronicity. SETTING: Two rehabilitation centers. PARTICIPANTS: Stroke participants (n = 40) with plantar flexor spasticity, treated with BT-A (200 units) into the gastrocnemius muscle. METHODS: Outcome parameters were reanalyzed serially using 2-way repeated measures of analysis of variance (ANOVA), at baseline and 2, 4, and 8 weeks postinjection. Subjects were reclassified into 3 groups: early, within 6 months (n = 12); middle, between 6 months and 1 year (n = 14); and late, between 1 and 2 years from stroke onset (n = 12). MAIN OUTCOME MEASURES: The Modified Ashworth Scale, clonus scale, 10-m walking test, ABILOCO, and the Functional Ambulation Category. RESULTS: The 2-way repeated measures of ANOVA showed improvement in gait and spasticity after injection in the 3 groups. Significant improvement in the Modified Ashworth Scale (P < .001) was observed, starting from the post-2 week injection period. Improvement of gait as assessed by the functional measurement ABILOCO and the Functional Ambulation Category (P < .001) were observed in all 3 groups, mostly at the post-8 week injection period. CONCLUSIONS: Our serial measurements of the outcome parameters indicated that BT-A could be expected to lead to consistent improvement in both the muscle tone and gait quality in those with plantar flexor spasticity regardless of stroke chronicity, including those injected as early as within the first 6 months. LEVEL OF EVIDENCE: I.


Asunto(s)
Toxinas Botulínicas Tipo A/uso terapéutico , Extremidad Inferior/fisiopatología , Espasticidad Muscular/tratamiento farmacológico , Fármacos Neuromusculares/uso terapéutico , Accidente Cerebrovascular/fisiopatología , Adulto , Anciano , Método Doble Ciego , Femenino , Trastornos Neurológicos de la Marcha/tratamiento farmacológico , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Espasticidad Muscular/fisiopatología , Prueba de Paso , Adulto Joven
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