Search results for " Transient"

Measurement of ionization, charge exchange and ion confinement times in charge breeder ECR ion sources with short pulse 1+ injection of metal ions

2022

Abstract The Consecutive Transients (CT) method is used for estimating the characteristic times of ionization, charge exchange and confinement within the plasma of a Charge Breeder Electron Cyclotron Resonance Ion Source (CB-ECRIS). The method reveals differences in the characteristic times between different source configurations, with K9+ charge breeding efficiencies of 8.9 % and 20.4 %, and allows qualitative explanation of the improved breeding efficiency. The increase in K9+ efficiency is accompanied by a decrease in ionization time for low charge states, a decrease of charge exchange time for high charge states, and an overall decrease of the ion confinement time, which increases non-l…

Transient Focal Neurological Events in Cerebral Amyloid Angiopathy and the Long-term Risk of Intracerebral Hemorrhage and Death: A Systematic Review …

2021

Importance Transient focal neurological episodes (TFNEs) are a frequently overlooked presentation of cerebral amyloid angiopathy (CAA), a condition with prognostic implications that are still not well described. Objective To perform a systematic review and meta-analysis to examine the factors associated with incident lobar intracerebral hemorrhage (ICH) and death in patients with CAA presenting with TFNEs. Data Sources A systematic review and individual participant meta-analysis including (1) a hospital-based cohort and (2) the results obtained from a systematic search performed in MEDLINE and Embase completed in December 2019. Study Selection Included studies were observational reports of …

Prevalence, predictors, and severity of lean nonalcoholic fatty liver disease in patients living with human immunodeficiency virus

2020

Abstract Background The burden of nonalcoholic fatty liver disease (NAFLD) is growing in people living with human immunodeficiency virus (HIV). NAFLD is associated with obesity; however, it can occur in normoweight (lean) patients. We aimed to investigate lean NAFLD in patients living with HIV. Methods We included patients living with HIV mono-infection from 3 prospective cohorts. NAFLD was diagnosed by transient elastography (TE) and defined as controlled attenuation parameter ≥248 dB/m, in absence of alcohol abuse. Lean NAFLD was defined when a body mass index was <25 kg/m2. Significant liver fibrosis was defined as TE ≥7.1 kPa. The presence of diabetes, hypertension, or hyperlipid…

Prevalence and risk factors for advanced liver fibrosis in HIV/HCV-coinfected individuals

2010

Neuronal nitric oxide synthase is involved in CB/TRPV1 signalling: Focus on control of hippocampal hyperexcitability

2017

Cannabinoids (CB), transient receptors potential vanilloid type 1 (TRPV1) and nitric oxide (NO) were found to be interlinked in regulating some neuronal functions such as membrane excitability and synaptic transmission. TRPV1 play a fundamental role since it represents a synaptic target for CB that triggers several downstream cellular pathways. In this regard, recent evidence report that TRPV1 could influence NO production by modulating neuronal NO synthase (nNOS) activity. In the present research, we pointed to manipulate nNOS function to assess its role on TRPV1 signalling in hyperexcitability conditions elicited in the dentate gyrus of hippocampal formation. The activation of TRPV1 recep…

Faim2 contributes to neuroprotection by erythropoietin in transient brain ischemia.

2018

Delayed cell death in the penumbra region of acute ischemic stroke occurs through apoptotic mechanisms, making it amenable to therapeutic interventions. Fas/CD95 mediates apoptotic cell death in response to external stimuli. In mature neurons, Fas/CD95 signaling is modulated by Fas-apoptotic inhibitory molecule 2 (Faim2), which reduces cell death in animal models of stroke, meningitis, and Parkinson disease. Erythropoietin (EPO) has been studied as a therapeutic strategy in ischemic stroke. Erythropoietin stimulates the phosphatidylinositol-3 kinase/Akt (PI3K/Akt) pathway, which regulates Faim2 expression. Therefore, up-regulation of Faim2 may contribute to neuroprotection by EPO. Male Faim…

Obesity and Abdominal Fat Markers in Patients with a History of Stroke and Transient Ischemic Attacks.

2016

Background Abdominal obesity is a well-recognized cardiovascular risk factor. Conflicting data concerning its significance with respect to stroke have been discussed in recent years. The objective of this study was to analyze the association between anthropometric parameters and the risk of stroke and transient ischemic attacks (TIAs) in German primary care. Methods Patient recruitment in this large-scale epidemiological study was performed in 3188 representative primary care offices in Germany. Among 6980 study participants, 1745 patients with a history of stroke or TIA were identified and matched for age and gender with 5235 regional controls. Associations between standard anthropometric …

Cerebral metabolism after transient ischemic attack. A 1H MR spectroscopy study

1999

International audience; Abstract: Metabolic changes induced by cerebral infarction or by stenosis and occlusion of the internal carotid artery have been previously described in 1H Magnetic Resonance Spectroscopy (1H MRS). These changes are essentially characterized by decreased N-acetyl-aspartate (NAA) and increased lactate concentration. Little is known about the metabolic changes observed in the three days following a transient ischemic attack (TIA) in the absence of stenosis or occlusion of the internal carotid artery, and without visible infarction on Magnetic Resonance imaging (MRI). We studied five patients with a TIA lasting between 30 min and 3 h, affecting the sensory and motor fun…

Prescription of Antithrombotic Therapy in Older Patients Hospitalized for Transient Ischemic Attack and Ischemic Stroke: The GIFA Study

2004

Background and Purpose— Antithrombotic therapy has been demonstrated as an effective tool for secondary ischemic stroke prevention. Nevertheless, scant data are available on actual prescription of this therapy in clinical practice. Methods— A total of 17 337 patients admitted to geriatric and internal medicine wards participating in the study in the 1993 to 1998 survey period were analyzed. Patients with coded diagnoses of ischemic stroke and transient ischemic attack (TIA) were selected. Data recorded included demographic and clinical characteristics and medication prescription during hospital stay and at discharge. Logistic regression analyses were used to identify conditions associated …

Inhibition of iNOS activity by 1400W decreases glutamate release and ameliorates stroke outcome after experimental ischemia

2005

Background and purpose. It has been shown that the reversed operation of glutamate transporters when ATP levels fall accounts for most glutamate release induced by severe cerebral ischemia. Nitric oxide (NO) is formed after ischemia and causes ATP depletion. Our purpose is to test if NO release from inducible NO synthase (iNOS) after stroke may cause a delayed glutamate release due to ATP depletion that might underlie progression of the ischemic infarct. We have studied the effect of the highly selective inhibitor of iNOS activity 1400W on brain ATP levels, extracellular glutamate, and stroke outcome after transient focal cerebral ischemia in rats. Methods. To induce focal ischemia, the mid…