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AbstractThe purpose of this study was to investigate the possible involvement of endothelium-derived hyperpoiarizing factor in endothelium-dependent relaxation of the cerebral vasculature by testing the effectiveness of NO synthase inhibitors at inhibiting endothelium-dependent relaxation in the rabbit basilar artery. Acetylcholine (1.0pM) and 0.1/0.2pM sarafotoxin S6c, an endothelinBreceptor agonist, relaxed serotonin constricted basilar artery in situ by 100% and 70%, respectively. Nc-monomethyl-L-arginine (L-NMMA; 0.1 mM) and 0.3 mM Nc-nitro-L-arginine (L-NNA), NO synthase Inhibitors, decreased the 1.0 pM acetylcholine- and 0.1/0.2 pM sarafotoxin S6c-induced relaxations by 75% and 45%, respectively. Unexpectedly, the relaxations were abolished by the combination of L-NMMA plus L-NNA. Furthermore, L-arginine (1.0 mM), but not D-arginine, restored the relaxations. Sodium nitroprusside-induced relaxation was also inhibited by L-NMMA plus L-NNA, and the inhibition was reversed by L-arginine. KCI constricted vessels only minimally relaxed in response to sodium nitroprusside, acetylcholine, and sarafotoxin S6c. These results demonstrate that combined NO synthase inhibitors more effectively inhibit endothelium-dependent relaxation than a single inhibitor. The mechanism underlying the greater inhibition due to the combined NO synthase inhibitors may result from both decreased NO release and secondary effects caused by decreased NO release, such as membrane depolarization. The results further suggest that caution should be used with respect to suggestions of the involvement of endothelium-derived hyperpoiarizing factor in endothelium-dependent relaxation based upon the partial inhibitory effects of NO synthase inhibitors. [Neurol Res 2000; 22: 204—208]

The dura mater has attracted considerable attention as an exquisitely sensitive tissue implicated as playing a role in various cephalalgias including vascular headache. Because of the potential clinical impact of the relationship/interaction of neural elements and mast cells the influence of sensory and autonomic nerve fibres on mast cells of the rat dura mater was studied. The trigeminal or superior cervical ganglion was electrically stimulated and the mast cells were examined. Wholemount supratentorial dural preparations were stained using berberine sulphate and the number of mast cells with intact vs dispersed granules counted. Unilateral stimulation of either ganglia resulted in a statistically significant increase in the percentage of mast cells with dispersed granules ipsilateral to the side of stimulation. These results support our idea that in addition to the trigeminal system the sympathetic nervous system must be considered as playing a role in the oedema pathophysiology of vascular headache.

Summary We report 36 cases of post-traumatic “primary brain stem haemorrhage” visualized by the CT scan and confirmed at autopsy.

Summary We report 17 cases of chronic extradural haematoma out a total of 411 epidural haematomas treated at the Neurosurgical Department of Padua from 1954 to 1980.

The prognostic value in 49 children and 56 adults of the following parameters recorded on admission was analyzed: oculocephalic and light reflexes, posturing, Glasgow Coma Scale (GCS), the need for ventilatory support, and the presence of associated injuries. All patients had been in coma for at least 6 h. The presence of intracranial hematoma and the duration of coma were recorded and the relative risk of poor outcome calculated. There was poor outcome in 51% of the children and 61% of the adults. Oculocephalic and light reflexes, posturing, GCS, need for ventilatory support, and duration of coma were significantly related to the outcome in children. Only oculocephalic and light reflexes, and posturing were significantly related to the outcome in adults. Some parameters appeared to have different prognostic value in children and in adults: the simultaneous evaluation of oculocephalic reflex and need for ventilation was the best prognostic guide in children, the light reflex was the best prognostic indicator in adults.

The outcome is reported in 62 children with severe head injuries following a road traffic accident. All patients were comatose for at least 6 h; all patients were graded using the Glasgow Coma Score (GCS) or the Children Coma Score (CCS). Fifty-four patients were comatose immediately after injury, 8 after a lucid interval. Thirty patients had isolated head injuries and 32 had associated injuries, either long bone fractures or rupture of an abdominal organ. Additional information concerning main brainstem reflexes, posture and respiration was included in the study. The overall mortality was 32%. The goal of the study was to identify those clinical features available soon after injury which are important indicators of treatment and outcome.

Summary Of a series of 350 patients studied for blunt head trauma by CT scan 10 were found to have an intraventricular haemorrhage (IVH); in 8 cases we could find concomitant CT abnormalities as well as intracerebral contusion or haemorrhage, and in two cases no other CT abnormality was noted.

Summary A case is presented in which the delayed development of a traumatic intracerebellar haematoma was documented by CT scan. The onset of “transitory psychotic behaviour” is reported. Possible mechanisms for the delayed evolution of an intraparenchymal haematoma and for the manifestation of such a syndrome are discussed.

Summary A 49-year-old man was submitted to neurosurgery for a cranio-pharyngioma.

Summary Two rare cases of osteomatous meningioma of the spinal cord are described. The capacity of these neoplasms to produce bone trabeculae represents one of the many potentialities of differentiation of meningioma cells, which may come from neural crest cells. This histogenetic derivation is sustained by the association of a meningioma with a schwannoma in the second case.

Summary A case of enlargement of a middle cerebral artery aneurysm is reported. Cerebral angiography demonstrated an increase in the size of this aneurysm. Possible factors causing aneurysmal enlargement are discussed.

Summary Case histories are reported of 18 patients in whom the diagnosis of primary brain stem haematoma5 and brain stem haemorrhage13 was made by computed tomography (CT).

Summary While the presence of a robust perivascular neural network accompanying cerebral and dural blood vessels that contain various neuropeptides is well documented, the functional significance of this innervation is unclear.

Summary An experimental model was used to investigate acute alterations of cerebral metabolic activity in rats subjected to subarachnoid haemorrhage (SAH). Haemorrhages were produced in anaesthetized animals by injecting 0.3 ml of autologous, arterial nonheparinized blood into the cisterna magna. Control rats received subarachnoid injections of mock-cerebrospinal fluid to study the effect of sudden raised intracranial pressure, or underwent sham operation. Three hours after SAH rats were given an intravenous injection of [14C]-2-deoxyglucose. Experiments were terminated by decapitation, and the brains were removed and frozen. Regional brain metabolic activity was studied by quantitative autoradiography. In comparison with sham-operated controls, cerebral metabolic activity was diffusely decreased after SAH. Statistically significant decreases in metabolic rate were observed in 23 of 27 brain regions studied. Subarachnoid injections of mock-cerebrospinal fluid also produced depression of cerebral metabolic activity, but quantitatively these changes were not as pronounced and diffuse as in SAH rats. The present study shows that a widespread depression of brain metabolism occurs in the acute stage after experimental SAH and is probably secondary to the Subarachnoid presence of blood itself and/or blood products.

Surgical specimens of 4 intracranial saccular aneurysms were studied by scanning electron microscopy. The internal surface of the aneurysms showed crater-like defects and cytoplasmic bridges. In some areas the endothelium was preserved, but its longitudinal convolutions were higher and thicker than those found in unchanged areas. On the damaged endothelial surface there was an increased number of blood cells. The adventitia resembled that of a normal cerebral artery. In conclusion the alterations observed are similar to those found in atherosclerosis and are most likely dut to the high wear and tear provoked by the blood streaming into the aneurysm. The results of this study are in agreement with the findings of a companion transmission electron microscopy study and emphasize the importance of degenerative changes on the development and rupture of intracranial saccular aneurysms.

Summary Thromboxane, a highly vasoactive substance, is found in the cerebrospinal fluid of patients and experimental animals following subarachnoid haemorrhage. A stable synthetic analogue of thromboxane A2 was administered intracisternally in rabbits. This resulted in an increase in endothelial permeability of the major cerebral arteries to Evans Blue dye and horseradish peroxidase. Thromboxane may be involved in the pathogenesis of cerebral vasospasm and may be related to the contrast enhancement of the arteries in the basal cisterns on CT scans of patients who are prone to develop arterial narrowing.

Summary In order to gather fundamental information about the reanimative, diagnostic, and therapeutic measures concerning head-injured patients, we propose the introduction of an “Admission Chart”.

Summary We report 298 patients admitted to the Neurosurgical unit of the University of Padua during one calendar year. We divided the patients into two groups. “in coma” and “not in coma”, and analyze their data records. The time between injury and admission to a neurosurgical centre is important for therapy as well as for transport.

Summary We report 14 cases of vertex epidural haematomas among 478 cases of epidural haematomas that were hospitalized in the Neurosurgical Department of the University Hospital of Padova during the period 1953–1980.

Summary We report ten cases of post-traumatic posterior fossa haemorrhage occurring in children. All patients were studied by CT scan. Five had an intracerebellar haemorrhage, three a brain stem haemorrhage, and two an extradural haematoma. In four cases we have found the coexistence of supratentorial and infratentorial haemorrhagic lesions.

Summary The coincidence of vascular malformation and primary brain neoplasm is very rare.

Summary:  Objective and Importance. Spontaneous spinal subarachnoid hematoma is rare, having been reported in the English literature in only seven other cases. We describe the first case of spontaneous subarachnoid hematoma located in the cervical spinal cord of a 43-year-old man. The pathologic examination showed no apparent source of bleeding, but there was evidence of cervical spondylotic myelopathy.  Clinical Presentation. The patient presented with a 10-day history of severe neck pain, followed by the onset of quadriparesis that was more evident on the left side, urinary retention, and sensory loss below C5. His medical history included hypertension. Magnetic resonance imaging showed a massive hemorrhage in the cervical spinal canal.  Intervention. A C4-C5 subarachnoid hematoma was removed. The patient died due to respiratory distress and uncontrollable hypotension on day 6 after surgery. Surgical exploration, neuroradiologic examinations, and autopsy showed no evidence of vascular malformations, tumors, or other possible sources of bleeding.  Conclusion. After excluding more common causes of spontaneous subarachnoid hematoma in this patient, we suggest that chronic spinal cord compression (spondylotic myelopathy) and arterial hypertension in this patient may have caused the pathogenesis of this rare clinical entity. Experimental data supporting this hypothesis are discussed.

An unusual case of a chronic posttraumatic lumbar intradural arachnoid cyst causing compression of the cauda equina is reported. The etiological, pathological, and clinical features are discussed. Emphasis is placed on the importance of a correct interpretation of radiological findings.