RESUMEN
BACKGROUND: Post-stroke pneumonia (PSP) is common among stroke patients. PSP occurring after hospital discharge continues to increase the risk of poor functional outcomes and death among stroke survivors. Currently, there is no prediction model specifically designed to predict the occurrence of PSP beyond the acute stage of stroke. This study aimed to explore the use of machine learning (ML) methods in predicting the risk of PSP after hospital discharge. METHODS: This study analyzed data from 5,754 hospitalized stroke patients. The dataset was randomly divided into a training set and a holdout test set, with a ratio of 80:20. Several clinical and laboratory variables were utilized as predictors and different ML algorithms were employed to model time-to-event data. The ML model's predictive performance was compared to existing risk-scoring systems. A model-agnostic method based on Shapley additive explanations was utilized to interpret the ML model. RESULTS: The study found that 5.7% of the study patients experienced pneumonia within one year after discharge. Based on repeated 5-fold cross-validation on the training set, the random survival forest (RSF) model had the highest C-index among the various ML algorithms and traditional Cox regression analysis. The final RSF model achieved a C-index of 0.787 (95% confidence interval: 0.737-0.840) on the holdout test set, outperforming five existing risk-scoring systems. The top three important predictors were the Glasgow Coma Scale score, age, and length of hospital stay. CONCLUSIONS: The RSF model demonstrated superior discriminative ability compared to other ML algorithms and traditional Cox regression analysis, suggesting a non-linear relationship between predictors and outcomes. The developed ML model can be integrated into the hospital information system to provide personalized risk assessments.
Asunto(s)
Neumonía , Accidente Cerebrovascular , Humanos , Alta del Paciente , Aprendizaje Automático , Neumonía/epidemiología , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Análisis de SupervivenciaRESUMEN
PURPOSE: Ischemic penumbra is the main therapeutic target for acute ischemic stroke. The aim in this study is to investigate the potential serum biomarkers of penumbra that could fulfill a complementary role in the acute stroke clinical decision-making process. EXPERIMENTAL DESIGN: An established focal cerebral ischemia model is applied in rats. Using isobaric tags for relative and absolute quantitation combined with liquid chromatography-tandem mass spectrometry, the global expression profiles of proteins in ischemic penumbra tissue and serum from rats subjected to different ischemic times are identified and quantified. Candidate biomarkers are screened out with bioinformatics analysis and further validated by western blotting. RESULTS: Herein, a total of 4568 proteins in the penumbra and 1915 proteins in the serum are identified. Two proteins related to the penumbra, RHOA, and CDC42, are screened out through an integrative analysis. The expression levels of RHOA and CDC42 in the penumbra and serum gradually increase synchronously with the prolonged ischemia time. CONCLUSIONS AND CLINICAL RELEVANCE: The study provides the results of a proteomic analysis to identify serum biomarkers of the penumbra. Upregulation of RHOA and CDC42 may be useful for the early assessment of ischemic penumbra and could serve as potential serum biomarkers.
Asunto(s)
Isquemia Encefálica/metabolismo , Proteómica , Accidente Cerebrovascular/complicaciones , Enfermedad Aguda , Animales , Biomarcadores/sangre , Isquemia Encefálica/sangre , Isquemia Encefálica/complicaciones , Isquemia Encefálica/patología , Perfilación de la Expresión Génica , Masculino , Ratas , Ratas Sprague-Dawley , Espectrometría de Masas en TándemRESUMEN
BACKGROUND: miR-146a, a strong pro-apoptotic factor in some pathophysiological processes, is reported to be involved in ischemic stroke (IS), though its role remains unclear. Fbxl10 is an active anti-apoptotic factor and a predicted target of miR-146a. We hypothesized that dysregulation of miR-146a contributes to ischemic injury by targeting Fbxl10. METHODS: Circulating miRNAs were detected by miRNA microarray and qRT-PCR. miR-146a targets were predicted using bioinformatics and confirmed with a dual luciferase reporter assay. We used an in vitro ischemic model of oxygen-glucose deprivation and reperfusion (OGD/R) to mimic cerebral ischemia/reperfusion (I/R) conditions. Expression of miR-146a, Fbxl10 and Bcl2l2 mRNAs, and Fbxl10 and Bcl2l2 proteins was verified by qRT-PCR and Western blotting. The effects of miR-146a on neuronal cell apoptosis were evaluated by flow cytometry. RESULTS: A significant reduction in miR-146a expression was observed in acute ischemic stroke (AIS). A dual-luciferase reporter assay showed that Fbxl10, but not Bcl2l2, is a target of miR-146a. Transfection with miR-146a mimics promoted apoptosis in SK-N-SH cells and significantly reduced expression of Fbxl10. Conversely, miR-146a inhibition attenuated OGD/R-induced neuronal cell death and significantly up-regulated Fbxl10 expression. CONCLUSIONS: miR-146a expression was significantly down-regulated in AIS, and Fbxl10 was identified as a target of miR-146a. Moreover, up-regulation of Fbxl10, a miR-146a target, likely protects neurons from ischemic death.
Asunto(s)
Apoptosis/fisiología , Isquemia Encefálica/sangre , Proteínas F-Box/sangre , Histona Demetilasas con Dominio de Jumonji/sangre , MicroARNs/sangre , Accidente Cerebrovascular/sangre , Anciano , Isquemia Encefálica/diagnóstico por imagen , Línea Celular Tumoral , Proteínas F-Box/genética , Femenino , Expresión Génica , Células HEK293 , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Masculino , MicroARNs/genética , Persona de Mediana Edad , Análisis por Matrices de Proteínas/métodos , ARN Mensajero/sangre , ARN Mensajero/genética , Accidente Cerebrovascular/diagnóstico por imagenRESUMEN
BACKGROUND: Neurogenic neuroprotection is a promising approach for treating patients with ischemic brain lesions. Fastigial nucleus stimulation (FNS) has been shown to reduce the tissue damage resulting from focal cerebral ischemia in the earlier studies. However, the mechanisms of neuroprotection induced by FNS remain unclear. MicroRNAs (miRNAs) are a newly discovered group of non-coding small RNA molecules that negatively regulate target gene expression and involved in the regulation of pathological process. To date, there is a lack of knowledge on the expression of miRNA in response to FNS. Thus, we study the regulation of miRNAs in the rat ischemic brain by the neuroprotection effect of FNS. METHODS: In this study, we used an established focal cerebral ischemia/reperfusion (IR) model in rats. MiRNA expression profile of rat ischemic cortex after 1 h of FNS were investigated using deep sequencing. Microarray was performed to study the expression pattern of miRNAs. Functional annotation on the miRNA was carried out by bioinformatics analysis. RESULTS: Two thousand four hundred ninety three miRNAs were detected and found to be miRNAs or miRNA candidates using deep sequencing technology. We found that the FNS-related miRNAs were differentially expressed according microarray data. Bioinformatics analysis indicated that several differentially expressed miRNAs might be a central node of neuroprotection-associated genetic networks and contribute to neuroprotection induced by FNS. CONCLUSIONS: MiRNA acts as a novel regulator and contributes to FNS-induced neuroprotection. Our study provides a better understanding of neuroprotection induced by FNS.
Asunto(s)
Núcleos Cerebelosos , Biología Computacional , Estimulación Encefálica Profunda , Secuenciación de Nucleótidos de Alto Rendimiento , MicroARNs/genética , Neuroprotección/genética , Análisis de Secuencia de ARN , Animales , Isquemia Encefálica/complicaciones , Masculino , Anotación de Secuencia Molecular , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/complicaciones , Daño por Reperfusión/genética , Daño por Reperfusión/fisiopatología , Daño por Reperfusión/terapiaRESUMEN
MicroRNAs have been discovered as regulators of gene expression and thus their potential in clinical disease diagnostics, prognosis and therapy is being actively pursued. MicroRNAs play an important role in atherosclerosis-related diseases, such as cerebrovascular and cardiovascular disease. However, the effect of miR-185 and miR-146a on patients with ischemic stroke (IS) in the different phases has not been reported. In this study, we investigated the amounts of three miRNAs, miR-185, miR-146a, and miR-145 in blood circulation of IS patients. We enrolled 60 patients with IS in the acute or sub-acute phase and 30 healthy controls. We divided the patients into two groups, patients with ischemic stroke in the acute phase (ISA) and patients with ischemic stroke in the subacute phase (ISS). We measured circulating miRNAs expression by miRNA microarray and real-time polymerase chain reaction (PCR) analysis. Testing by miRNA microarray and RT-PCR analyses showed that miR-145 levels in healthy subjects were similar to patients with IS, whereas miR-146a and miR-185 were present with quite low abundance in ISA compared with healthy individuals; moreover, we found that miR-146a levels were downregulated in ISA but upregulated in ISS which may help provide new insights into the diagnosis and therapy of IS.
Asunto(s)
Isquemia Encefálica/complicaciones , Regulación de la Expresión Génica/fisiología , MicroARNs/metabolismo , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/genética , Anciano , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Análisis por Micromatrices , Persona de Mediana Edad , ARN Mensajero/metabolismo , Curva ROC , Estadística como Asunto , Accidente Cerebrovascular/metabolismo , Factores de TiempoRESUMEN
Previous studies have shown that fastigial nucleus stimulation (FNS) reduces tissue damage resulting from focal cerebral ischemia. Although the mechanisms of neuroprotection induced by FNS are not entirely understood, important data have been presented in the past two decades. MicroRNAs (miRNAs) are a newly discovered group of non-coding small RNA molecules that negatively regulate target gene expression and are involved in the regulation of cell proliferation and cell apoptosis. To date, no studies have demonstrated whether miRNAs can serve as mediators of the brain's response to FNS, which leads to endogenous neuroprotection. Therefore, this study investigated the profiles of FNS-mediated miRNAs. Using a combination of deep sequencing and microarray with computational analysis, we identified a novel miRNA in the rat ischemic cortex after 1 h of FNS. This novel miRNA (PC-3p-3469_406), herein referred to as rno-miR-676-1, was upregulated in rats with cerebral ischemia after FNS. In vivo observations indicate that this novel miRNA may have antiapoptotic effects and contribute to neuroprotection induced by FNS. Our study provides a better understanding of neuroprotection induced by FNS. MicroRNA (miRNA) is defined as a small non-coding RNA that fulfills both the expression and biogenesis criteria. Here, we describe a novel miRNA in the rat ischemic cortex expressed after 1 h of fastigial nucleus stimulation (FNS). The miRNA was functionally characterized by secondary structure, quantitative expression, the conservation analysis, target gene analysis, and biological functions. We consider rno-miR-676-1 to be a true microRNA and present evidence for its neuroprotective effects exerted after induction by FNS.
Asunto(s)
Núcleos Cerebelosos/fisiología , Terapia por Estimulación Eléctrica , Infarto de la Arteria Cerebral Media/fisiopatología , MicroARNs/biosíntesis , Animales , Secuenciación de Nucleótidos de Alto Rendimiento , Etiquetado Corte-Fin in Situ , Masculino , Análisis de Secuencia por Matrices de Oligonucleótidos , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
AIMS: Studies showed fastigial nucleus stimulation (FNS) reduced brain damage, but the mechanisms of neuroprotection induced by FNS were not entirely understood; MicroRNAs are noncoding RNA molecules that regulate gene expression in a posttranscriptional manner, but their functional consequence in response to ischemia-reperfusion (IR) remains unknown. We investigated the role of microRNA-29c in the neuroprotection induced by FNS in rat. METHODS: The IR rat models were conducted 1 day after FNS. Besides, miR-29c antagomir (or agomir or control) was infused to the left intracerebroventricular 1 day before IR models were conducted. We detected differential expression of Birc2 mRNA (also Bak1mRNA and miR-29c) level among different groups by RT-qPCR. The differential expression of Birc2 protein (also Bak1 protein) level among different groups was surveyed via Western blot. The neuroprotective effects were assessed by infarct volume, neurological deficit, and apoptosis. RESULTS: MiR-29c was decreased after FNS. Moreover, miR-29c directly bound to the predicted 3'-UTR target sites of Birc2 and Bak1 genes. Furthermore, over-expression of miR-29c effectively reduced Birc2 (also Bak1) mRNA and protein levels, increased infarct volume and apoptosis, and deteriorated neurological outcomes, whereas down-regulation played a neuroprotective role. CONCLUSIONS: MiR-29c correlates with the neuroprotection induced by FNS by negatively regulating Birc2 and Bak1.