Ischemic stroke is a devastating condition lacking effective therapies. A promising approach to attenuate ischemic injury is mild hypothermia. Recent studies show that adenosine nucleotides can induce hypothermia in mice. The purpose of the present study was to test the hypothesis that adenosine 5'-triphosphate (ATP) induces mild hypothermia in rats and reduces ischemic brain injury. We found that intraperitoneal injections of ATP decreased core body temperature in a dose-dependent manner; the dose appropriate for mild hypothermia was 2 g/kg. When ATP-induced hypothermia was applied to stroke induced by middle cerebral artery occlusion, however, a neuroprotective effect was not observed. Instead, the infarct volume grew even larger in ATP-treated rats. This was accompanied by an increased rate of seizure events, hemorrhagic transformation, and higher mortality. Continuous monitoring of physiologic parameters revealed that ATP reduced heartbeat rate and blood pressure. ATP also increased blood glucose, accompanied by severe acidosis and hypocalcemia. Western blotting showed that ATP decreased levels of both phospho-Akt and total-Akt in the cortex. Our results reveal that, despite inducing hypothermia, ATP is not appropriate for protecting the brain against stroke. Instead, we show for the first time that ATP treatment is associated with exaggerated ischemic outcomes and dangerous systemic side effects.

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lation of miR-384-5p attenuates rotenone-induced neurotoxicity in dopaminergic SH-SY5Y cells through inhibiting endoplasmic reticulum stress. Am J Physiol Cell Physiol 310: C755-C763, 2016. First published February 10, 2016 doi:10.1152/ajpcell.00226.2015.-Endoplasmic reticulum (ER) stress has been linked to the pathogenesis of Parkinson's disease (PD). However, the role of microRNAs (miRNAs) in this process involved in PD remains poorly understood. Recent studies indicate that miR-384-5p plays an important role for cell survival in response to different insults, but the role of miR-384-5p in PD-associated neurotoxicity remains unknown. In this study, we investigated the role of miR-384-5p in an in vitro model of PD using dopaminergic SH-SY5Y cells treated with rotenone. We found that miR-384-5p was persistently induced by rotenone in neurons. Also, the inhibition of miR-384-5p significantly suppressed rotenone-induced neurotoxicity, while overexpression of miR-384-5p aggravated rotenone-induced neurotoxicity. Through bioinformatics and dual-luciferase reporter assay, miR-384-5p was found to directly target the 3=-untranslated region of glucose-regulated protein 78 (GRP78), the master regulator of ER stress sensors. Quantitative polymerase chain reaction and Western blotting analysis showed that miR-384-5p negatively regulated the expression of GRP78. Inhibition of miR-384-5p remarkably suppressed rotenone-evoked ER stress, which was evident by a reduction in the phosphorylation of activating transcription factor 4 (ATF4) and inositol-requiring enzyme 1 (IRE1␣). The downstream target genes of ER stress including CCAAT/enhancer-binding protein-homologous protein (CHOP) and X box-binding protein-1 (XBP-1) were also decreased by the miR-384-5p inhibitor. In contrast, overexpression of miR-384-5p enhanced ER stress signaling. In addition, knockdown of GRP78 significantly abrogated the inhibitory effect of miR-384-5p inhibitors on cell apoptosis and ER stress signaling. Moreover, we observed a significant increase of miR-384-5p expression in primary neurons induced by rotenone. Taken together, our results suggest that miR-384-5p mediated ER stress by negatively regulating GRP78 and that miR-384-5p inhibition might be a novel and promising approach for the treatment of PD. endoplasmic reticulum stress; Parkinson's disease; miR-384-

Antiplatelet agents, especially aspirin, are effective for the prevention of secondary stroke and cardiovascular diseases, and have been widely used in most patients in China. Long-term antiplatelet therapy reduces the risk of recurrent stroke, myocardial infarction, and vascular death in patients with stroke or ischemic heart disease, but it may be associated with increased risk of intracerebral hemorrhage (ICH), [1][2][3][4] which is an uncommon but often fatal or disabling treatment complication. Identification of risk factors will therefore help to prevent ICH in patients receiving aspirin, especially in long-term users.Cerebral microbleeds (CMBs) are considered to be indicative of bleeding-prone microangiopathy and ICH. They appear as round hypointense regions on T2*-weighted magnetic resonance ABSTRACT: Background: The objective of the study was to determine the frequency of cerebral microbleeds (CMBs) by using phasesensitive imaging in patients with previous transient ischemic attack (TIA) or stroke who were receiving aspirin treatment. Methods: We retrospectively analyzed 300 outpatients with ischemic cerebrovascular disease: 150 had been receiving aspirin treatment for >1 year (patients), and 150 controls had not previously received aspirin. Cerebral microbleeds were defined by a trained observer (blinded to clinical details) according to results of T2-weighted, T1-weighted, diffusion-weighted, and phase-sensitive magnetic resonance imaging (MRI). Numerous vascular risk factors including white matter hyperintensity (WMH), duration of aspirin treatment, age, hypertension or diabetes mellitus were investigated for a possible association with the presence of CMBs in the two groups. Results: The frequency of CMBs (60/150 (40% ) vs 18/150 (12%); odds ratio 4.899, p <0.0001) and intracerebral hemorrhage (ICH)(42/150 (28% ) vs 2/150 (1%); odds ratio 28.778, p <0.0001) were significantly higher in the patients than in the controls. Among patients, those using aspirin for >5 years(42/68 (62%) showed a higher frequency of CMBs than those receiving aspirin for ≤ 5 years(18/82 (22%); odds ratio 5.744, p<0.0001). WMH (p=0.020/0.030, 0.007/0.000) age (p=0.007/0.000) and hypertension (p=0.000/0.033), in patients and controls respectively, were each associated with CMBs. Conclusions: There was a clear impact of aspirin treatment on CMBs associated with intracerebral hemorrhage in Chinese patients. The frequency of CMBs and hemorrhagic complications was higher in patients treated with long-term aspirin.RÉSUMÉ: Le traitement par l'aspirine augmente le risque de micro saignements cérébraux. Contexte : L'objectif de l'étude était de déterminer la fréquence de micro saignements cérébraux (MSC) au moyen de l'imagerie par contraste de phase chez les patients qui recevaient de l'aspirine suite à des accès ischémiques transitoires cérébraux (ITC) ou à un accident vasculaire cérébral. Méthode : Nous avons analysé rétrospectivement les dossiers de 300 patients externes atteints d'une maladie cérébrovasculaire ischémique : 150 re...

ObjectivesTo evaluate the predictive value of radiomics features based on multiparameter magnetic resonance imaging (MP-MRI) for peritoneal carcinomatosis (PC) in patients with ovarian cancer (OC).MethodsA total of 86 patients with epithelial OC were included in this retrospective study. All patients underwent FS-T2WI, DWI, and DCE-MRI scans, followed by total hysterectomy plus omentectomy. Quantitative imaging features were extracted from preoperative FS-T2WI, DWI, and DCE-MRI images, and feature screening was performed using a minimum redundancy maximum correlation (mRMR) and least absolute shrinkage selection operator (LASSO) methods. Four radiomics models were constructed based on three MRI sequences. Then, combined with radiomics characteristics and clinicopathological risk factors, a multi-factor Logistic regression method was used to construct a radiomics nomogram, and the performance of the radiomics nomogram was evaluated by receiver operating characteristic curve (ROC) curve, calibration curve, and decision curve analysis.ResultsThe radiomics model from the MP-MRI combined sequence showed a higher area under the curve (AUC) than the model from FS-T2WI, DWI, and DCE-MRI alone (0.846 vs. 0.762, 0.830, 0.807, respectively). The radiomics nomogram (AUC=0.902) constructed by combining radiomics characteristics and clinicopathological risk factors showed a better diagnostic effect than the clinical model (AUC=0.858) and the radiomics model (AUC=0.846). The decision curve analysis shows that the radiomics nomogram has good clinical application value, and the calibration curve also proves that it has good stability.ConclusionRadiomics nomogram based on MP-MRI combined sequence showed good predictive accuracy for PC in patients with OC. This tool can be used to identify peritoneal carcinomatosis in OC patients before surgery.