Molecular neurobiology
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Molecular neurobiology · May 2016
Meta AnalysisHyperglycemia and Mortality Risk in Patients with Primary Intracerebral Hemorrhage: A Meta-Analysis.
Hyperglycemia may be associated with worse functional outcomes in patients with primary intracerebral hemorrhage. We performed a systematic review and meta-analysis to investigate the relationship between hyperglycemia and mortality risk in patients with primary intracerebral hemorrhage. We searched PubMed and Embase databases for studies investigating the association between hyperglycemia and mortality risk in patients with primary intracerebral hemorrhage. ⋯ Subgroup analysis by time of follow-up showed that hyperglycemia significantly increased risk of short-term mortality (RR = 3.97, 95% CI 2.13-7.43) and long-term mortality (RR = 1.53, 95% CI 1.14-2.05). The RR of mortality for per 1-mmol/L increment in glucose level was 1.14 (95% CI 1.06-1.22). In patients with primary intracerebral hemorrhage, hyperglycemia significantly increases risk of both short-term mortality and long-term mortality.
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Molecular neurobiology · May 2016
Plasma Homocysteine Levels Predict the Risk of Acute Cerebral Infarction in Patients with Carotid Artery Lesions.
This study examined the association between elevated plasma homocysteine (Hcy) levels and the risk of acute cerebral infarction in patients with carotid artery lesions. A total of 78 patients were divided into two groups, the high Hcy group (n = 38; Hcy levels >15 umol/L) and the low Hcy group (n = 40; Hcy levels ≤15 umol/L). High-resolution B-mode ultrasounds were performed to assess intima media thickness (IMT), infarcts, plaques, and stenosis in the extracranial carotid artery of these patients. ⋯ Pearson's test indicated that plasma Hcy levels positively correlated with IMT, total number of plaques and unstable plaques. Overall, the elevated plasma Hcy levels correlated with increased frequency of carotid plaque formation, extra- and intracranial arterial stenosis, and the degree of stenosis. In conclusion, we find a significant correlation between elevated plasma Hcy levels and the increased incidence of acute cerebral infarction in patients with carotid artery lesions.
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Molecular neurobiology · May 2016
Dexmedetomidine Dose-Dependently Attenuates Ropivacaine-Induced Seizures and Negative Emotions Via Inhibiting Phosphorylation of Amygdala Extracellular Signal-Regulated Kinase in Mice.
Ropivacaine (Ropi), one of the newest and safest amino amide local anesthetics, is linked to toxicity, including the potential for seizures, changes in behavior, and even cardiovascular collapse. Dexmedetomidine (Dex), an α2-adrenergic receptor agonist, has been widely used in anesthesia and critical care practice. To date, the underlying mechanisms of the effects of Dex premedication on Ropi-induced toxicity have not been clearly identified. ⋯ Open-field (OF) and elevated plus maze (EPM) test were used to measure negative behavioral emotions such as depression and anxiety. Immunohistochemistry and Western blot were utilized to investigate phosphorylation-extracellular regulated protein kinases (p-ERK) expression in the basolateral amygdala (BLA) on 2 h and in the central amygdala (CeA) on 24 h after convulsion in mice. The results of our investigation demonstrated that Dex dose-dependently increased RopiCD50, prolonged the latency and shortened the duration of each RopiCD50-induced seizure, improved the negative emotions revealed by both OF and EPM test, and inhibited p-ERK expression in the BLA and the CeA.
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Molecular neurobiology · May 2016
Calpain-Dependent ErbB4 Cleavage Is Involved in Brain Ischemia-Induced Neuronal Death.
Disturbance of neuregulin-1β/ErbB4 signaling is considered to be associated with brain ischemia, but the mechanisms of this disruption are largely unknown. In the present study, we provide evidence that degradation of ErbB4 is involved in neuronal cell death in response to ischemia. Our data showed that the application of neuregulin-1β provided significant protection against oxygen-glucose deprivation (OGD)-induced neuronal death as detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, annexin V/propidium iodide flow cytometry analysis and terminal deoxynucleotidyl transferase (TdT) dUTP nick end labeling (TUNEL) staining. ⋯ In vitro studies further indicated that recombinant calpain induced the cleavage of ErbB4 in a dose-dependent way, whereas the calpain inhibitor significantly reduced the OGD-induced ErbB4 breakdown. Additionally, OGD-induced apoptosis was partially abolished by transfection with the ErbB4E872K mutant. Taken together, neuregulin-1β elicits its neuroprotective effect in an ErbB4-dependent manner, and the cleavage of ErbB4 by calpain contributes to a neuronal cell death cascade during brain ischemia.