Surface Properties of Synaptosomes in the Presence of L-Glutamic and Kainic Acids: In Vitro Alteration of the ATPase and Acetylcholinesterase Activities

Morphologically and functionally identical to brain synapses, the nerve ending particles synaptosomes are biochemically derived membrane structures responsible for the transmission of neural information. Their surface and mechanical properties, measured in vitro, provide useful information about the functional activity of synapses in the brain in vivo. Glutamate and kainic acid are of particular interest because of their role in brain pathology (including causing seizure, migraine, ischemic stroke, aneurysmal subarachnoid hemorrhage, intracerebral hematoma, traumatic brain injury and stroke). The effects of the excitatory neurotransmitter L-glutamic acid and its agonist kainic acid are tested on Na+, K+-ATPase and Mg2+-ATPase activities in synaptic membranes prepared from the cerebral cortex of rat brain tissue. The surface parameters of synaptosome preparations from the cerebral cortex in the presence of L-glutamic and kainic acids are studied by microelectrophoresis for the first time. The studied neurotransmitters promote a significant increase in the electrophoretic mobility and surface electrical charge of synaptosomes at 1–4 h after isolation. The measured decrease in the bending modulus of model bimolecular membranes composed of monounsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine provides evidence for softer membranes in the presence of L-glutamate. Kainic acid does not affect membrane mechanical stability even at ten-fold higher concentrations. Both the L-glutamic and kainic acids reduce acetylcholinesterase activity and deviation from the normal functions of neurotransmission in synapses is presumed. The presented results regarding the modulation of the enzyme activity of synaptic membranes and surface properties of synaptosomes are expected by biochemical and biophysical studies to contribute to the elucidation of the molecular mechanisms of neurotransmitters/agonists’ action on membranes.

Prognostic Indicators in Patients with Intracerebral Hematoma in an urban clinical setting of a resource limited Country

Context and Objective: Hemorrhagic Cerebrovascular Accidents represent 10 to 15% of all strokes and are often related to the spontaneous rupture of small vessels weakened by chronic arterial hypertension or amyloid angiopathy. The aim of this work was to study the prognostic determinants of intracerebral haematomas at the neurology department of Conakry University Hospital. Patients and Method: This was a retrospective analytical study conducted on all patients who were hospitalized with intracerebral hematoma over the 24-month period. Only the records of patients in whom intracerebral hematoma was confirmed by brain imaging were included in this study. Logistic regression (uni-variate and multi-variate) identified prognostic determinants of intracerebral hematoma at p < 0.05. The data were entered using Epi Info software version 7.1.4.0 then analysed using STATA / SE software version 11.2. Results: This study found 21% of cases of intracerebral hematomas during the study period, with a male predominance of 60% and a sex ratio of 1.50. The study was conducted in the presence of a male patient. Hypertension was the cause found in 89.52% of patients; followed by arteriovenous malformations in 6.67% of patients, 2.86% of cases of amyloid angiopathy and 0.95% of unknown cause. Nevertheless, we still recorded 20% of deaths during hospitalization. Conclusion: Previous quality of life and co-morbidities also modify the prognosis and should be taken into account in the prediction of disability and future quality of life of patients with intracerebral haematoma.

From Spot Sign to Bleeding on the Spot: Classic and Original Signs of Expanding Primary Spontaneous Intracerebral Hematoma

Expansion of a primary spontaneous intracranial hemorrhage (PSICH) has become lately of increasing interest, especially after the emergence of its early predictors. However, these signs lacked sensitivity and specificity. The flood phenomenon, defined as a drastic increase in the size of a PSICH during the same magnetic resonance study, was first described in this paper based on the data of a university medical center in Lebanon. Moreover, further review of this data resulted in 205 studies with presumed diagnosis of primary spontaneous intracranial hemorrhage within the last 10 years, of which 29 exams showed typical predictors of hematoma expansion on computed tomography. The intended benefit of this observation is to draw the radiologists’ attention towards minimal variations in the volume of the hematoma between the two extreme sequences of the same MRI study, in order to detect inconspicuous flood phenomena—a direct sign of hematoma expansion.

Surgery of hypertensive intracranial hematomas using one-portal mini-access and video endoscopic assistance

Background. Hypertensive intracranial hemorrhage is an extremely serious complication of hypertension, which accounts for 10 % to 20 % of all cerebral strokes. About 50 % patients die within the next year, and their 5-year survival rate does not exceed 30 %. Objective. To study the effectiveness of surgical treatment of hypertensive intracranial hematomas using one-portal mini-access and video endoscopic assistance. Design and methods. The study included 23 patients with supratentorial intracerebral hypertensive hematomas aged 26 to 70 years (median age 55 (50; 61) years). All patients underwent one-portal endoscopic surgery. The median volume of intracerebral hematoma, calculated according to the Tada formula, was 50 (40; 60) ml. The comparison group included 28 patients who received conservative treatment. The dynamics of the severity was assessed using the Glasgow Coma Scale (GCS), NIHSS, Rankin, Rivermead scales upon admission to the hospital, on days 3 and 7 of treatment, at discharge for outpatient treatment, and after 6 months.Results. There were no lethal outcomes in either the main group or the comparison group. The hematoma was removed totally in all patients, which was accompanied by a rapid improvement of general cerebral symptoms and, as a consequence, an increase in GCS values from 13 (12; 14) to 13 (12; 15) points by 3rd day after the disease onset. By the 7th day, there was a slow positive dynamic in both groups, however, all patients still had a pronounced or severe disability according to the Rankin scale. After 6 months, patients who underwent surgical treatment showed faster and more complete recovery. Conclusions. The results of the study are consistent with current worldwide data on the effectiveness of modern endoscopic technologies in patients with hypertensive intracerebral hemorrhage in relation to the rate and degree of regression of neurological loss.

A-52 Evolving Cognitive and Neuropsychiatric Sequelae of Ruptured Arteriovenous Malformation Following Neurosurgical Intervention

Objective Arteriovenous malformations (AVMs) are tangled masses of arteries and veins of congenital origin. AVMs are rare (~4.3% in the general population) and symptomatic cases are rarer still (0.1–1%). AVMs account for strokes in 1–2% of cases. We present the case of a 59-year-old, right-handed, Caucasian male, with nine years of formal education, who was evaluated as an inpatient following a ruptured AVM. Method Patient with known history of AVM (Figure 1) presented with headache and new onset seizure. Computerized tomography (CT) revealed rupture of an AVM at the right temporal-occipital junction, with resulting intraparenchymal hemorrhage within the right parieto-occipital lobe and the right ventricular system and 0.8 cm left midline shift (Figure 2). The patient underwent emergency craniotomy for evacuation of intracerebral hematoma, resection of AVM, and placement of right external ventricular drain (EVD). Electroencephalograom (EEG) revealed focal cortical dysfunction over the right hemisphere and moderate encephalopathy. Results (Table 1). Neuropsychological evaluation six days following emergency craniotomy revealed primary impairment in visuoperceptual and visuoconstructional skills (including left neglect; Figures 3 & 4), impairments in working memory, learning/memory of verbal information (with intact recognition), as well as impairment in aspects of language (semantic fluency). These were accompanied by dense anosagnosia pertaining to cognitive deficits, but intact insight related to his hospitalization. Conclusions This is a rare case of symptomatic AVM with neuropsychological evaluation data highlighting the associated evolving cognitive (e.g., left neglect and visuoperceptual disturbance) and neuropsychiatric deficits (e.g., dense anosagnosia) in the context of recent neurosurgical interventions (e.g., evacuation of hemorrhage, placement of EVD, etc.).