Comparative analysis of brain electric activity after intraventricular administration of GABA and glutamate: It there any correlation between specific neurochemical modifications in the brain and EEG changes?

1997 ◽  
Vol 124 (2) ◽  
pp. 776-779
Author(s):  
A. V. Yarkov ◽  
V. V. Gal'chenko ◽  
G. I. Kovalev
2017 ◽  
pp. 8-17
Author(s):  
A. A. Ermakova ◽  
O. Yu. Borodin ◽  
M. Yu. Sannikov ◽  
S. D. Koval ◽  
V. Yu. Usov

Purpose: to investigate the diagnostic opportunities of contrast  magnetic resonance imaging with the effect of magnetization transfer effect in the diagnosis of focal metastatic lesions in the brain.Materials and methods.Images of contrast MRI of the brain of 16  patients (mean age 49 ± 18.5 years) were analysed. Diagnosis of  the direction is focal brain lesion. All MRI studies were carried out  using the Toshiba Titan Octave with magnetic field of 1.5 T. The  contrast agent is “Magnevist” at concentration of 0.2 ml/kg was  used. After contrasting process two T1-weighted studies were  performed: without T1-SE magnetization transfer with parameters of pulse: TR = 540 ms, TE = 12 ms, DFOV = 24 sm, MX = 320 × 224  and with magnetization transfer – T1-SE-MTC with parameters of pulse: ΔF = −210 Hz, FA(МТС) = 600°, TR = 700 ms, TE = 10 ms,  DFOV = 23.9 sm, MX = 320 x 224. For each detected metastatic  lesion, a contrast-to-brain ratio (CBR) was calculated. Comparative  analysis of CBR values was carried out using a non-parametric  Wilcoxon test at a significance level p < 0.05. To evaluate the  sensitivity and specificity of the techniques in the detection of  metastatic foci (T1-SE and T1-SE-MTC), ROC analysis was used. The sample is divided into groups: 1 group is foci ≤5 mm in size, 2  group is foci from 6 to 10 mm, and 3 group is foci >10 mm. Results.Comparative analysis of CBR using non-parametric Wilcoxon test showed that the values of the CBR on T1-weighted  images with magnetization transfer are significantly higher (p  <0.001) that on T1-weighted images without magnetization transfer. According to the results of the ROC analysis, sensitivity in detecting  metastases (n = 90) in the brain on T1-SE-MTC and T1-SE was  91.7% and 81.6%, specificity was 100% and 97.6%, respectively.  The accuracy of the T1-SE-MTC is 10% higher in comparison with  the technique without magnetization transfer. Significant differences (p < 0.01) between the size of the foci detected in post-contrast T1- weighted images with magnetization transfer and in post-contrast  T1-weighted images without magnetization transfer, in particular for  foci ≤5 mm in size, were found. Conclusions1. Comparative analysis of CBR showed significant (p < 0.001)  increase of contrast between metastatic lesion and white matter on  T1-SE-MTC in comparison with T1-SE.2. The sensitivity, specificity and accuracy of the magnetization transfer program (T1-SE-MTC) in detecting foci of  metastatic lesions in the brain is significantly higher (p < 0.01), relative to T1-SE.3. The T1-SE-MTC program allows detecting more foci in comparison with T1-SE, in particular foci of ≤5 mm (96% and 86%, respectively, with p < 0.05).


1995 ◽  
Vol 8 (2) ◽  
pp. 109-114 ◽  
Author(s):  
A. O. Ogunyemi

Migraine with prolonged aura has rarely been examined with regard to the sequence of the neurological symptoms and the associated EEG changes. This report describes five patients who underwent clinical assessment and EEG recordings during attacks of migraine with prolonged aura. CT scan of the brain was obtained in four of them. Follow-up EEG was also obtained. The aura symptoms either preceded the headache or were coincident with it. The aura symptoms evolved in a manner consistent with posterior-to-anterior dysfunction of the cerebral cortex. The EEG abnormalities were non-epileptiform and consisted of focal delta slow waves or theta slow waves. The EEG abnormalities showed good correlation with the patients' aura symptoms and resolved when the patients became symptom free. The posterior-to-anterior sequence of the aura symptoms is in accord with the findings during cerebral blood flow studies in patients having migraine with aura. Also the symptoms and EEG changes in our patients indicate dysfunction of the cerebral cortex, consistent with the notion that spreading cortical depression may be the underlying pathophysiological event in migraine with aura.


Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Douglas M Bennion ◽  
Lauren Donnangelo ◽  
David Pioquinto ◽  
Robert Regenhardt ◽  
Mohan K Raizada ◽  
...  

Background: Toward discovering novel stroke therapies, recent research has shown that activation of the newly-discovered angiotensin converting enzyme 2/angiotensin-(1-7)/mas (ACE2/Ang-(1-7)/Mas) pathway, a counter-regulatory axis of the brain renin-angiotensin system, is neuroprotective in ischemic stroke in rats. Specifically, intraventricular administration of the novel ACE2 activator diminazine aceturate (DIZE) before and during an ischemic stroke decreases cerebral infarct and neurologic deficits. Efficacy must now be demonstrated using minimally-invasive methods if this therapy is to be translated to the care of human patients. In this study, we assessed the hypothesis that systemic administration of DIZE post ischemic stroke would be neuroprotective. Methods: Adult male Sprague-Dawley rats underwent ischemic stroke by endothelin-1 induced middle cerebral artery occlusion and were randomly divided into 2 groups (n=9-10/set): 1) intraperitoneal (IP) administrations of DIZE (7.5 mg/kg) at 4, 24, and 48 h after stroke; 2) IP administrations of 0.9% saline vehicle at the same time points. At 24 and 72 h after stroke, rats underwent blinded neurologic assessments. Immediately following the 72 h tests, animals were sacrificed, cerebral infarct volumes assessed by TTC staining, and IL-1β expression in the stroke region analyzed by rt-PCR. Data are expressed as mean ± SEM with significance inferred at p<0.05. Results: Mean infarct volume was significantly decreased by IP injections of DIZE (9.4% ± 4.35) as compared to control (22.8%±3.6, p=0.039). At 24 h post stroke, neurologic deficits (Garcia Scale) were significantly improved in the DIZE treated group (16.7±0.40) versus the saline group (15.22±0.57, p=0.037). Although DIZE tended to improve neurologic deficits 72 h post stroke, this trend was not significant. Finally, DIZE treatment significantly reduced mRNA expression of IL-1β (0.43 ± 0.14) in the cerebral cortical stroke region as compared to saline treatment (1.47±0.08, p=0.001). Conclusions: Our findings suggest that targeting the ACE2/Ang-(1-7)/Mas axis post stroke can improve function, decrease inflammation, and reduce infarct volume - a significant translational step in brain renin-angiotensin system research.


1971 ◽  
Vol 50 (1) ◽  
pp. 51-58 ◽  
Author(s):  
A. PECILE ◽  
E. E. MÜLLER ◽  
M. FELICI ◽  
C. NETTI ◽  
D. COCCHI

SUMMARY Injections of insulin (0·2 or 0·01 i.u./20 μl) into the lateral ventricle of the rat brain, while not changing blood glucose levels or altering the pituitary content of growth hormone (GH), blocked the release of GH from the pituitary and the decrease of growth-hormone releasing activity (GHRF) of stalk median eminence (SME) extracts in the presence of the hypoglycaemic effect on insulin (2 i.u./kg) given intraperitoneally. Intraventricular administration of insulin also impaired the GH release elicited by cold exposure (4 °C, 1 h) but not the release induced by electric shock. The possibility that insulin injected into the brain acts on glucose-sensitive GH-regulating structures is suggested.


2007 ◽  
Vol 51 (2-4) ◽  
pp. 85-91 ◽  
Author(s):  
Hideo Taniura ◽  
Judy C.G. Sng ◽  
Yukio Yoneda

1996 ◽  
Vol 726 (1-2) ◽  
pp. 174-180 ◽  
Author(s):  
N.V. Gulyaeva ◽  
N.A. Lazareva ◽  
M.L. Libe ◽  
O.S. Mitrokhina ◽  
M.V. Onufriev ◽  
...  

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