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J Aasly

Publications and source records attributed to J Aasly.

50 records · Page 3Linked to original sources
PubMed1990

Evaluation of early and late presented tasks in the intracarotid Amytal test for epileptic patients.

The temporal relation between speech and somatomotor effects was analyzed in 24 epileptic patients who underwent bilateral intracarotid Amytal tests. Furthermore, a chronological study of the task presentation was carried out. The memory test included 3 pre- and 12 post-injection items, the latter consisting of 6 words and 6 concrete pictures. Both hemispheres had low free verbal recall capacity. The speech-dominant hemisphere recognized 45% of the words and 58% of the pictures; the non-dominant side 17% and 32%, respectively. An epileptic lesion in the right temporal lobe only reduced the word recognition at a statistically significant level. Despite the early start of task presentation, both hemispheres recognized the early items almost as well as those presented later. This makes it possible for an extensive test battery which in turn helps to quantify memory capacity. If this method is used to test hemisphere memory, the possibility of interhemispheric cooperation is reduced, thereby increasing the validity of the results. The results are discussed in relation to intra- and interhemispheric communication during amobarbital sedation and regression.

Adolescent↗
PubMed1990

Early mitochondrial changes in chronic progressive ocular myopathy.

Two sisters with chronic progressive external ophthalmoplegia (CPEO) and their in all 7 healthy children were investigated. Both ophthalmoplegic patients had histopathological changes typical of mitochondrial myopathy. The same type of muscular pathology was also found among the healthy children. The most common muscular changes were subsarcolemmal accumulation of pathological mitochondria, including vacuoles, abnormal cristae and sometimes also inclusion bodies. Biochemical studies showed partial complex III deficiency, with low succinate-cytochrome c reductase activity in 1 of the ophthalmoplegic patients. These findings suggest that CPEO is a slowly progressive muscle disease, starting early in life. The widespread occurrence among the children may indicate maternal inheritance.

Adolescent↗
PubMed1989

[Experiences with ambulatory radiculography].

54 outpatients who were referred with the clinical diagnosis lumbar disk herniation, underwent lumbar myelography with iohexol. After the examination the patient returned to the ward where he was observed for about 2 hours while resting in a chair. He was then allowed to leave the hospital with the recommendation to avoid hard physical exercise for the next 24 hours. No serious complications occurred. Severe headache was reported by 20% of the patients and 22% experienced transient minor discomfort. It is concluded that lumbar iohexol myelography can be performed safely on ambulatory patients.

Adult↗
PubMed1989

Barbiturate effects on EEG abnormality in complex partial epilepsy.

Sixteen patients with drug-resistant complex partial epilepsy were, during preoperative investigations for surgical treatment, subjected to intravenous methohexital and amobarbital EEG activation tests. The interictal epileptic spike discharges were visually counted on the seizure-generating side and compared with those found in the contralateral hemisphere. The invasive recordings were made with depth electrodes implanted in the mesial temporal lobes of 5 patients, and with subdural strip electrodes in varying lateral positions over the frontotemporal-parietal lobes of the other 11 patients. The doses of 10% amobarbital, 50-200 mg, were too low to induce any significant activation. In eight patients with unilateral epileptic lesions, 10, 25 and 50 mg 1% methohexital, induced a dose-dependent increase in the interictal spiking, always higher on the side of the seizure-gererating focus. Asymmetric induction of beta activity was noted in five patients. The test gave valuable information when determining the type or location of the epileptic abnormality. Parallels were drawn with earlier studies on spike-activation tests after intracarotid amobarbital injections. Although administered differently, the barbiturates are supposed to act directly on the neurons, and not via integrative wakening mechanisms.

Adult↗
PubMed1987

The effect of progesterone and its metabolites on the interictal epileptiform discharge in the cat's cerebral cortex.

The antiepileptic effect of progesterone, 5-alpha-pregnane-3,20-dione, 3-alpha-hydroxy-5-alpha-pregnane-20-one, and 3-alpha-hydroxy-5-beta-pregnane-20-one were tested in an experimental animal model, and compared with the effect of clonazepam. The steroids were dissolved in serum from ovariectomized cats. Ovariectomized adult cats were used and spontaneous epileptic discharges were generated by placing small pieces of penicillin-soaked filter papers on the ipsi and contralateral cerebral cortex. The frequency and amplitude of the interictal epileptiform spikes were recorded, and analysed in a computer. The changes in frequency and amplitudes were calculated. The drugs were infused during 20-s periods into one cerebral hemisphere via the ipsilateral lingual artery with speeds of 1.1, 3.4 and 6.3 ml min-1. A penicillin focus on the contralateral hemisphere served as a simultaneous control. Progesterone and clonazepam showed similar inhibitory effects on epileptiform interictal spiking (median reduction of spike frequency 21%, cf. Table I). The 5-alpha-pregnane-3, 20-dione was generally less potent than progesterone (median reduction 9%) and the 5-alpha- and 5-beta-pregnanolones were two to three times more potent than progesterone (54-66% reduction). The latency of the inhibitory effect was 4-10 s measured from the entrance of the infusion into the lingual artery. The depression lasted 10-20 min. It is concluded that the pregnanolones have strong antiepileptic properties. The rapid onset of effect indicates that the steroids may interact with the neuronal function at the membrane or synaptic levels.

5-alpha-Dihydroprogesterone↗
PubMed1986

Chronic paroxysmal hemicrania. X. On the autonomic involvement.

In four patients with chronic paroxysmal hemicrania, two of whom could precipitate attacks mechanically, various autonomic function tests were carried out in connection with attacks. Not all features could be studied in all patients. Forehead sweating and temperature were measured. Sweating, tearing, and nasal secretion were studied after systemic atropine administration, which reduced attack-related sweating, tearing, and nasal secretion markedly. Intra-ocular pressure was measured before and after the topical administration of an alpha-receptor blocking agent, thymoxamine. After topical thymoxamine no definite intra-ocular pressure increase occurred during precipitated attacks. In attacks precipitated by head movements, forehead sweating occurred seconds (up to 30 sec) before the pain. This study indicates that at least in some CPH cases, forehead sweating is not caused by the pain. Nor is the pain secondary to increase in intra-ocular pressure. The thymoxamine experiments seem to indicate that alpha-receptors in some way may be connected with the intra-ocular pressure increase during attack.

Atropine↗
PubMed1986

A method for recording effects of anti-epileptic drugs on interictal discharge in the cat's cerebral cortex. Factors determining the distribution of external carotid artery infusions.

The method utilizes infusion via the external carotid (ECA), the internal maxillary arteries and their anastomoses to the cerebral circulation. It takes into account the ipsilateral distribution of the carotid blood supply. A regular interictal epileptiform spiking from foci on both hemispheres was provided by local application to the cortical surface of small pieces of filter paper soaked in sodium benzylpenicillin, 100,000 IE ml-1. The infused drug affects the ipsilateral foci, and the contralateral one functions as a simultaneous untreated control. The stability of the interictal frequency and the effect of non-oxygen carrying solvents are described. The effect of changes in blood pressure, temperature and PCO2 are considered as well as the coupling between activity in ipsi- and contralateral foci. Experiments with infused radioactive microspheres were performed to determine the strictness of the ipsilateral distribution and the conditions under which it was upheld. With mean arterial blood pressures between 70 mm Hg and 170 mm Hg and infusion speeds between 1.0 ml min-1 and 6.3 ml min-1 the distribution to the contralateral cerebral hemisphere was 0.3% (SD 0.2, SEM 0.1). Infusions of [125I]albumin were used to determine the blood flow in ECA. The flow varied between 20 ml min-1 and 68 ml min-1. The higher values were seen when the extracerebral shunting was high. Conditions influencing the dilution of the infusion and its distribution within the brain were investigated. Important factors were carotid and cerebral blood flow, arterial blood pressure, speed and duration of the infusion, recirculation and cerebral temperature. Arterial PCO2, pH and PO2 should be carefully controlled. Computer-supported treatment of interictal spike frequency and amplitude, as well as of circulatory and respiratory parameters, was utilized. The method was tested in experiments with infusions of 5 alpha-pregnanolone. It was shown that infusions, shorter than the estimated circulation time, reduced the interictal spike frequency and amplitude recorded from the ipsilateral foci without effects on the contralateral ones.

Animals↗
PubMed1984

Effects of amobarbital and methohexital on epileptic activity in mesial temporal structures in epileptic patients. An EEG study with depth electrodes.

Bilateral intracarotidal Amytal (amobarbital) tests for evaluation of speech and memory function were performed during preoperative evaluation of 30 patients with drug-resistant epilepsy. In 8 of these patients (16 tests), having partial complex epilepsy, EEG was recorded with depth electrodes, implanted bilaterally in anterior mesial temporal structures. The EEGs during 13 tests could be quantified with regard to spike activity. A rapid increase in spike frequency was observed ipsilateral to the injection in all tests but one. No seizure activity or clinical seizures were provoked. This previously unnoticed effect of amobarbital could be due to a direct excitatory effect of the drug on epileptic temporal neurones or, alternatively, to a release of interictal inhibition, exerted upon these neurons by other structures. In 4 patients, the effect was compared with that of methohexital, another barbiturate known to have excitatory effects upon epileptic activity.

Action Potentials↗
PubMedDate not supplied

Cerebral hemisphere memory for manual object handling: an intracarotid Amytal study.

The memory capacity of the cerebral hemisphere for manual object handling was studied during preoperative, intracarotid Amytal testing for hemisphere speech and memory in 32 patients with intractable partial epilepsy. The tactile stereognostic memory was tested non-visually before and after amobarbital injection. Two common objects, one in each hand, were given to the patient with the request to identify each by manipulation, but not to name it. Before injection, object handling was carried out correctly by both hands. After injection, while the patient was hemiplegic, the dominant hemisphere executed the object handling correctly; the non-dominant hemisphere, however, did it less properly. Free verbal recall of the object presented before the injection was correct in 85%. The free verbal recall of the postinjection objects was much lower; 22% for the speech-dominant, and only 3% for the non-dominant hemisphere. Tactile, non-visual recognition gave a memory score of 41% for the speech-dominant, and 13% for the opposite hemisphere. An epileptic lesion in the dominant hemisphere impaired the memory performance of that hemisphere compared to the non-lesioned group.

Adolescent↗
PubMedDate not supplied

Mitochondrial diseases and myopathies: a series of muscle biopsy specimens with ultrastructural changes in the mitochondria.

From 1986 to 1991, 472 muscle biopsy specimens from patients from different hospitals in Norway were examined. Of these, 364 were embedded for electron microscopy, and 194 were examined with electron microscopy. Ultrastructural alterations in the mitochondria were detected in 49 of these specimens. Characteristic electron microscopic findings included subsarcolemmal accumulation of abnormal mitochondria of various shapes and sizes, often containing electron-dense granules and sometimes lipid vacuoles in the mitochondria and diffusely electron-lucent matrix space. Paracrystalline inclusion bodies were seldom seen in specimens from young patients, but in some cases mitochondrial electron-dense granules at the cristae were found. These amorphous densities are consistent with lipoproteins, suggesting that they may represent an early stage of paracrystalline inclusions. Biochemical and genetic exploration of the patients with biopsy specimens suggesting mitochondrial disease indicated maternally genetic inheritance and an enzyme defect in the respiratory chain in 21 patients in two families. Three patients had MELAS syndrome, 7 Marinesco-Sjögren syndrome, and 2 Kearns-Sayre syndrome. Five family members had ptosis, cardiomyopathy, mild myopathy, and increased lactate in cerebrospinal fluid and serum. In addition to the diseases mentioned above, changes in the mitochondria were detected in other conditions such as Rett's syndrome (n = 1), ornithine transcarbamylase deficiency (n = 2), and hypothyroidism (n = 2) as well as in 3 patients with clinical and laboratory results indicative of inflammatory myopathy and 3 patients with clinical and laboratory findings consistent with peripheral neuropathy. It is concluded that, although ultrastructural changes in the mitochondria may represent unspecific findings, electron microscopic examination of muscle biopsy specimens is a useful screening method to select specimens for further biochemical analysis and to obtain an early and more precise diagnosis of the disease.

Biopsy↗