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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.
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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.
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Células Endoteliais , Organoides , Humanos , Miócitos Cardíacos , Via de Sinalização Wnt , Fatores de Despolimerização de Actina , Matriz Extracelular , Neovascularização Patológica , IntegrinasRESUMO
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.
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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.
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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.
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Células-Tronco Pluripotentes Induzidas , Diferenciação Celular , Humanos , Mecanotransdução Celular , Miócitos Cardíacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
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.
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Ácido Ascórbico/farmacologia , Diferenciação Celular , Fator 4 de Crescimento de Fibroblastos/farmacologia , Células-Tronco Embrionárias Humanas/patologia , Modelos Biológicos , Miócitos Cardíacos/patologia , Estresse Fisiológico , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Meios de Cultura/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Ventrículos do Coração/patologia , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Humanos , Infarto do Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Transcriptoma/genéticaRESUMO
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.
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Proteínas de Homeodomínio , Células-Tronco Pluripotentes Induzidas , Fatores de Determinação Direita-Esquerda , Miócitos Cardíacos , Células-Tronco Pluripotentes , Fatores de Transcrição , Diferenciação Celular , Proteínas de Homeodomínio/metabolismo , Humanos , Fatores de Determinação Direita-Esquerda/metabolismo , Mesoderma , Organoides , Transdução de Sinais , Fatores de Transcrição/metabolismo , Proteína Homeobox PITX2RESUMO
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.
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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.
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[This corrects the article DOI: 10.1039/D0RA01577F.].
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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.
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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.
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Fibroblastos/citologia , Miócitos Cardíacos/citologia , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Biomimética , Bioimpressão , Comunicação Celular , Colágeno Tipo I/metabolismo , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Fator 4 de Crescimento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Humanos , Miócitos Cardíacos/metabolismoRESUMO
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.
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Hidroterapia/métodos , Articulação do Joelho/fisiopatologia , Paralisia/fisiopatologia , Paralisia/reabilitação , Equilíbrio Postural , Reabilitação do Acidente Vascular Cerebral/métodos , Humanos , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
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 6â¯months after stroke, 72.2% of patients had mRS score >3, with more women (81.0% vs. 66.0%, pâ¯=â¯0.024) showing poor recovery. Both men (51.3% vs. 35.9%, pâ¯=â¯0.041) and women (42.2% vs. 6.7%, pâ¯=â¯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]â¯=â¯2.61, 95% confidence interval [CI]: 1.14-5.98, pâ¯=â¯0.024) in men, but this association was notably stronger in women (ORâ¯=â¯9.93, 95% CI: 1.22-81.19, pâ¯=â¯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 2â¯weeks from stroke onset were more significantly likely to have a poor modified Rankin Scale after 6â¯months.
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Recuperação de Função Fisiológica/fisiologia , Sarcopenia/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento , Idoso , Estudos de Coortes , Feminino , Força da Mão , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Análise de Regressão , Estudos Retrospectivos , Fatores SexuaisRESUMO
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.
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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.
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Exercício Físico , Promoção da Saúde/métodos , Neoplasias da Próstata/reabilitação , Smartphone , Dispositivos Eletrônicos Vestíveis , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Estudos Prospectivos , República da CoreiaRESUMO
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.
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The composite cathode of an all-solid-state battery composed of various solid-state components requires a dense microstructure and a highly percolated solid-state interface different from that of a conventional liquid-electrolyte-based Li-ion battery. Indeed, the preparation of such a system is particularly challenging. In this study, quantitative analyses of composite cathodes by three-dimensional reconstruction analysis were performed beyond the existing qualitative analysis, and their microstructures and reaction interfaces were successfully analyzed. Interestingly, various quantitative values of structure properties (such as the volume ratio, connectivity, tortuosity, and pore formation) associated with material optimization and process development were predicted, and they were found to result in limited electrochemical charge/discharge performances. We also verified that the effective two-phase boundaries were significantly suppressed to â¼23% of the total volume because of component dispersion and packing issues.
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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.
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Tosse/diagnóstico , Transtornos de Deglutição/fisiopatologia , Pneumonia Aspirativa/diagnóstico , Testes de Função Respiratória/estatística & dados numéricos , Medição de Risco/métodos , Idoso , Área Sob a Curva , Ácido Cítrico , Bases de Dados Factuais , Transtornos de Deglutição/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Pico do Fluxo Expiratório , Pneumonia Aspirativa/etiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Valores de Referência , Testes de Função Respiratória/métodos , Estudos RetrospectivosRESUMO
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.