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BACKGROUND: Because of multiple competing death outcomes and time-varying coefficients, using a Cox regression model to analyze the prognostic factors of low-grade gliomas (LGG) may lead to a possible bias. Therefore, we adopted time-dependent competing risk models to obtain accurate prognostic factors for LGG. METHODS: In this retrospective cohort study, data were extracted from patients enrolled in the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2018. Univariate analysis was performed using the cumulative incidence function (CIF) and Kaplan-Meier (KM) function. Time-dependent competing risk and Cox regression models were used in the multivariable analysis. RESULTS: A total of 2581 patients were diagnosed with low-grade glioma, among whom 889 died from low-grade glioma, 114 died from other causes, and the rest were alive. The time-dependent competing risk models indicated that age, sex, marital status, primary tumor site, histological type, tumor diameter, surgery, and year of diagnosis were significantly associated with low-grade glioma-specific death, and the relative effect of age, tumor diameter, surgery, oligodendroglioma, and mixed glioma on low-grade glioma-specific death changed over time. Compared with the competing risk models, the Cox regression model misestimated the hazard ratio (HR) of covariates on the outcome and even produced false-negative results. CONCLUSIONS: The time-dependent competing risk models were better than the Cox regression model for evaluating the impact of covariates on low-grade glioma-specific mortality in the presence of competing risks and time-varying coefficients. The models identified the prognostic factors of LGG more accurately than the Cox regression model.
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Glioma , Projetos de Pesquisa , Humanos , Adulto , Prognóstico , Estudos Retrospectivos , Bases de Dados Factuais , Glioma/epidemiologiaRESUMO
Background: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an autosomal dominant inherited arterial disease, with lacunar infarction resulting from intracranial small vessel lesions being the most prevalent clinical manifestation of CADASIL. However, large-scale cerebral infarction caused by intracranial non-small vessels occlusion is relatively uncommon, and reports of vascular intervention and long-term antiplatelet drug treatment for patients with CADASIL and large-scale cerebral infarction are rarer. Methods: We reported a 52 year-old male who experienced a significant cerebral infarction due to an occlusion in the second segment of the left middle cerebral artery, 4 months subsequent to being diagnosed with CADASIL. Following the benefit and risk assessment, the patient underwent intracranial vascular thrombectomy and balloon dilation angioplasty. Subsequently, he was administered dual antiplatelet therapy for 3 months, followed by mono antiplatelet therapy. Results: After undergoing intracranial vascular intervention and receiving antiplatelet therapy, significant improvement in the symptoms were observed. The National Institutes of Health Stroke Scale score decreased from 6 to 2 points, and no bleeding lesions were detected on the head computed tomography during regular follow-up visits after discharge. Conclusion: Our case highlights the possibility that patients with CADASIL may also encounter extensive cerebral infarction resulting from stenosis or occlusion of intracranial non-small vessels. Considering the specific circumstances of the patient, intravascular intervention and antiplatelet therapy can be regarded as viable treatment options for individuals with CADASIL.
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Microvasculature of the retina is considered an alternative marker of cerebral vascular risk in healthy populations. However, the ability of retinal vasculature changes, specifically focusing on retinal vessel diameter, to predict the recurrence of cerebrovascular events in patients with ischemic stroke has not been determined comprehensively. While previous studies have shown a link between retinal vessel diameter and recurrent cerebrovascular events, they have not incorporated this information into a predictive model. Therefore, this study aimed to investigate the relationship between retinal vessel diameter and subsequent cerebrovascular events in patients with acute ischemic stroke. Additionally, we sought to establish a predictive model by combining retinal veessel diameter with traditional risk factors. We performed a prospective observational study of 141 patients with acute ischemic stroke who were admitted to the First Affiliated Hospital of Jinan University. All of these patients underwent digital retinal imaging within 72 hours of admission and were followed up for 3 years. We found that, after adjusting for related risk factors, patients with acute ischemic stroke with mean arteriolar diameter within 0.5-1.0 disc diameters of the disc margin (MAD0.5-1.0DD) of ≥ 74.14 µm and mean venular diameter within 0.5-1.0 disc diameters of the disc margin (MVD0.5-1.0DD) of ≥ 83.91 µm tended to experience recurrent cerebrovascular events. We established three multivariate Cox proportional hazard regression models: model 1 included traditional risk factors, model 2 added MAD0.5-1.0DD to model 1, and model 3 added MVD0.5-1.0DD to model 1. Model 3 had the greatest potential to predict subsequent cerebrovascular events, followed by model 2, and finally model 1. These findings indicate that combining retinal venular or arteriolar diameter with traditional risk factors could improve the prediction of recurrent cerebrovascular events in patients with acute ischemic stroke, and that retinal imaging could be a useful and non-invasive method for identifying high-risk patients who require closer monitoring and more aggressive management.
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Small extracellular vesicles (sEVs) contain abundant circular RNAs (circRNAs) and are involved in cellular processes, particularly hypoxia. However, the process that packaging of circRNAs into neuronal sEVs under hypoxia is unclear. This study revealed the spatial mechanism of the Fused in Sarcoma protein (FUS) that facilitates the loading of functional circRNAs into sEVs in hypoxia neurons. It is found that FUS translocated from the nucleus to the cytoplasm and is more enriched in hypoxic neuronal sEVs than in normal sEVs. Cytoplasmic FUS formed aggregates with the sEVs marker protein CD63 in cytoplasmic stress granules (SGs) under hypoxic stress. Meanwhile, cytoplasmic FUS recruited of functional cytoplasmic circRNAs to SGs. Upon relief of hypoxic stress and degradation of SGs, cytoplasmic FUS is transported with those circRNAs from SGs to sEVs. Validation of FUS knockout dramatically reduced the recruitment of circRNAs from SGs and led to low circRNA loading in sEVs, which is also confirmed by the accumulation of circRNAs in the cytoplasm. Furthermore, it is showed that the FUS Zf_RanBP domain regulates the transport of circRNAs to sEVs by interacting with hypoxic circRNAs in SGs. Overall, these findings have revealed a FUS-mediated transport mechanism of hypoxia-related cytoplasmic circRNAs loaded into sEVs under hypoxic conditions.
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We theoretically study the thermoelectric effect in a hybrid device composed by a topological semiconducting nanowire hosting Majorana bound states (MBSs) and a quantum dot (QD) connected to the left and right non-magnetic electrodes held at different temperatures. The electron-electron Coulomb interactions in the QD are taken into account by the non-equilibrium Green's function technique. We find that the sign change of the thermopower, which is useful for detecting the MBSs, will occur by changing the QD-MBS hybridization strength, the direct overlap between the MBSs at the opposite ends of the nanowire, and the system temperature. Large value of 100% spin-polarized or pure spin thermopower emerges even in the absence of Zeeman splitting in the QD or magnetic electrodes because the MBSs are coupled to electrons of only one certain spin direction in the QD due to the chiral nature of the Majorana fermions. Moreover, the magnitude of the thermopower will be obviously enhanced by the existence of MBSs.
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The purpose of this study was to develop an injectable submicron emulsion of eugenol (Eug-SE) and to investigate its antagonism on epilepsy. The formulation was optimized using a complete randomized design, comprising 5% (w/v) eugenol, 5% (w/v) soybean oil, 1.2% (w/v) egg phosphatidylcholine, 0.3% (w/v) poloxamer 188, and 0.03% (w/v) sodium oleate. The prepared Eug-SE was comprehensively evaluated in terms of its pharmaceutical characteristics, physicochemical stability, injection safety, antioxidant activity in vitro, and anti-epileptic effect in vivo. The mean particle size of Eug-SE was 176.1 ± 10.3 nm, the ζ-potential was -40.2 ± 1.8 mV, and the drug content was (95.3 ± 0.4) %. Moreover, the Eug-SE displayed excellent stability and improved safety compared to the eugenol solution. The Eug-SE (20 µg/mL) produced a significant neuroprotective effect against H2O2-induced oxidative damage in PC12 cells, which was attributed to the decrease of cellular reactive oxygen species level and mitochondrial damage. Besides, the in vivo test indicated that Eug-SE exerted an anti-epileptic effect in the PTZ treated mice. These results suggested that Eug-SE was a suitable dosage form of eugenol for injection, and displayed great therapeutic potential for neurological disease in the future.
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Anticonvulsivantes , Eugenol , Animais , Emulsões/farmacologia , Peróxido de Hidrogênio/farmacologia , Camundongos , Estresse Oxidativo , RatosRESUMO
OBJECTIVE: To acquire cDNA sequence of lecithin-cholesterol acyltransferase (LCAT) from tree shrew and analyze the sequence structure. METHODS: The first strand cDNA was acquired by reverse transcription using mRNA from tree shrew liver as template. By the method of SMART RACE PCR, tree shrew LCAT cDNA was acquired and deduced its amino acids sequence. The sequence and structure of tree shrew LCAT cDNA and amino acid were analyzed and predicted by the molecular software. RESULTS: Tree shrew LCAT cDNA is composed of 1,340 bp, including 2 bp 5' untranslated region (5' UTR), 1,320 bp open reading frame (ORF) which encodes protein precursor of 440 amino acids (24 amino acids signal peptide and 416 amino acids mature peptide), and 18 bp 3' untranslated region (3'UTR). The stop codon is TAA and there is a poly (A) signal sequence AATAAA and a 25 bp poly (A) tail. Tree shrew LCAT cDNA sequence has been accepted by GenBank as a new gene, accession number AF272861 and its homology with human and baboon was 90% and 89%, respectively. CONCLUSION: The sequence of LCAT cDNA in tree shrew has high identity with that of human and other experimental animal species.