Olle Nilsson

BRAIN INFARCTION IN YOUNG ADULTS

Sixty‐four young adults (aged 16 to 40 years) with ischemic stroke were analyzed in retrospect with regard to possible pathogenetic mechanisms. In older patients various predisposing factors emerge (arterial hypertension, hyperlipidemia etc.) which are rare among younger age groups. In patients lacking predisposing causes the stroke incidence exhibits a seasonal variation. It is suggested that infection may be important for the development of ischemic stroke.

Analysis of film coating thickness and surface area of pharmaceutical pellets using fluorescence microscopy and image analysis

A method is presented which enables geometrical characterisation of pharmaceutical pellets and their film coating. It provides a high level of details on the single pellet level. Image analysis was used to determine the coating thickness (h) applied on the pellets and the surface area (A) of the pellet cores. Different definitions of A and h are evaluated. Hierarchical analysis of variance was used to resolve different sources contributing to the total variance. The variance within pellets and the variance between pellets were found as significant sources of variation. Special emphasis was put on evaluation of A/h due to its influence on the release rate of an active drug substance from the pellet core. The pellet images were thus used to predict variations in the release rate using a mathematical model as a link between the image data and the release rate. General aspects of image analysis are discussed. The method would be useful in calibration of near infrared spectra to h in process analytical chemistry.

THE PROGNOSIS OF ISCHEMIC STROKE IN YOUNG ADULTS

The report provides prognostic information on 60 patients (aged 16 to 40 years) with ischemic stroke. Immediate mortality from stroke is low and long‐term mortality is due to other causes than cerehrovascular disease. The recovery from neurological deficits is good except for patients with occlusions of the internal carotic artery or the proximal part of the middle cerebral artery. Reinfarction is rare (about 0.5 per cent annually) and other late neurological complications do not seriously affect long‐term prognosis. More than 80 per cent of the patients will be able to resume work on a full or part‐time basis.

CLINICAL, NEUROPHYSIOLOGICAL AND MORPHOLOGICAL FINDINGS IN EATON LAMBERT SYNDROME

Two patients with maysthenic syndrome apparently not associated with carcinoma were studied in detail with repetitive stimulation of motor nerves, single fibre electromyography and histology. One patient showed signs of widespread autonomic dysfunction and the other patient had multifocal CNS symptoms of unclear etiology. Both cases showed a marked improvement with guanidine treatment which could be documented by the electrophysiological investigations. Due to severe adverse effects of the guanidine treatment on kidney, pancreatic and bone marrow functions the drug had to be withdrawn. Edrophonium given intravenously caused a marked and longlasting improvement of the muscle weakness and of the neurophysiological parameters. The mechanism of action is suggested to be different from that seen in myasthenia gravis. Single fibre electromyography showed a marked increase of neuromuscular jitter and blockings which decreased with increasing innervation frequency. The morphological study showed a selective affection of type II (fast twitch) fibres, a finding which is suggested to be secondary to an impaired neuromuscular transmission in the type II motor units.

EFFECT OF ENCEPHALITOGENIC PROTEIN ON MIGRATION IN AGAROSE OF LEUKOCYTES FROM PATIENTS WITH MULTIPLE SCLEROSIS

The literature on in vitro tests of sensitivity to brain antigen in multiple sclerosis is summarized in the tables. A study is presented using leukocyte migration in agarose as test system and a wide range of concentration of bovine encephalitogenic protein as antigen. Definite reactivity was seen in 12 out of 28 patients with MS. Some occurred in patients who had had no signs of disease activity for at least 5 years. Reactivity occurred more often in patients with active disease studied within 5 days after a relapse. The significance of the in vitro reactivity is briefly discussed.

EFFECT OF BASIC ENCEPHALITOGENIC PROTEIN AND SOME PEPTIDES DERIVED FROM IT ON THE MIGRATION IN AGAROSE GEL OF LEUKOCYTES FROM PATIENTS WITH MULTIPLE SCLEROSIS, OTHER NEUROLOGICAL DISEASES, OR CARCINOMA

Peripheral blood leukocytes from patients with multiple sclerosis (MS) or other diseases were studied using Clausens direct agarose gel migration method, with bovine encephalitogenic protein (BEP) and four peptides derived from it as antigens. Cells from healthy individuals show a slight and dose‐dependent inhibition with BEP. Of 35 cell samples from 24 MS patients, 16 showed a significantly stronger reaction, manifested either as inhibition or stimulation of migration, than that seen with cells from healthy individuals. Of 29 samples from 29 non‐MS patients, 6 showed such a reaction. In most instances, the reactivity to BEP could be localized to one or more of the peptides studied. There was no correlation established between peptide activity in the test and disease. A reactivity to the region containing the single tryptophan residue of the molecule (residue 116) could be demonstrated with cells from four patients: three had MS, the fourth had amyotrophic lateral sclerosis. One patient with active MS was followed for approx. two months, and definite changes in reactivity to BEP and the peptides were seen.

A study of some immunological variables in twins, discordant for multiple sclerosis

11 twin pairs, discordant for multiple sclerosis (MS), were studied: 5 were monozygotic, 6 dizygotic. The mixed leukocyte reaction (MLR) with cells from unrelated patients with MS, the natural killer cell (NK) activity, OKT 4/OKT 8 ratio, and monocyte numbers were studied. The impaired MLR seen in some patients with MS was even more pronounced in the healthy twin, irrespective of the zygosity of the twins. A reduced NK activity and a high OKT 4/OKT 8 ratio is seen in the diseased twin compared to the healthy one, more strongly indicated at monozygosity. The significance of genetics, early environment, and disease is discussed.

New halogen-specific detector applied to the analysis of chlorinated fatty acids

A new halogen-specific detection method (XSD) was tested for determination of chlorinated fatty acids in marine biota. In XSD, an increased emission of ions and electrons is caused by the high-temperature combustion of halogen-containing compounds. The detection limit of methyl dichlorooctadecanoate and the selectivity at a reactor temperature of 900 degrees C match those of electrolytic conductivity detection (ELCD). The relative standard deviation is less than 11% for > or =0.2 ng methyl dichlorooctadecanoate. An XSD chromatogram of a complex sample, chlorinated fatty acid methyl esters liberated from fish lipids, agreed with a previously obtained ELCD chromatogram.

Benign brainstem hematoma

Brainstem hematoma is generally considered a very rare condition with a grave prognosis. This report presents two patients with extensive brainstem hematomas who both recovered without major sequele. A brainstem hematoma is often impossible to differentiate from an infarction despite angiographic and cerebrospinal fluid examinations, but is readily disclosed by computerized tomography. It is suggested that the seriousness of the prognosis in brainstem hematoma may earlier have been exaggerated as there may have been a tendency to classify cases exhibiting a good recovery as infarcts, while the diagnosis hematoma was reserved for cases verified at autopsy.

The stretch reflex in the Eaton Lambert syndrome, myasthenia gravis and myotonic dystrophy.

The stretch reflex at rest and after muscle work was studied in three cases of Eaton Lambert syndrome. After muscle work a potentiation of the stretch reflex was demonstrated clinically and electrophysiologically. The presence of muscle stretch reflexes and their potentiation after muscle work was correlated with the clinical stage of the disease. The enhancement of the stretch reflex after voluntary effort was absent in normal subjects, myastehenia gravis and myotonic dystrophy.