Biomedical subjects
Publications and source records attributed to L Gjerstad.
Botulinum toxin A was administered to 19 patients with spasmodic torticollis. A significant decrease of abnormal head and neck movements was recorded, and all the patients who suffered pain reported relief. Side effects were minor and transient. The results of this study indicate that botulinum toxin is an effective means of treating torticollis.
Sixteen former rayon viscose workers were investigated four years after the exposure to carbon disulfide was discontinued. Median age was 58 years (range 43-65 years), median exposure time was 17 years (range 10-35 years). Encephalopathy was diagnosed in altogether 14 workers. To further explore pathophysiological mechanisms, cerebrovascular investigations were employed. Doppler ultrasound examination of the precerebral vessels in 15 workers showed a slight stenosis of the left internal carotid artery in one. Regional cerebral blood flow investigation (rCBF) with single photon emission computerized tomography (SPECT) with Xenon-133 gas was performed in 14. There was no significant difference from a control group. Regional side-to-side asymmetries beyond reference limits were demonstrated in eight workers. The abnormalities were modest, but may indicate a tendency toward focal blood flow disturbances in workers with long-term exposure to carbon disulfide.
Focal dystonia and hemifacial spasms are difficult to treat. Medication and surgery may suppress the dystonic movements but the improvement is not satisfactory. The present article reviews use of Botulinum toxin in cases of focal dystonia. Injections of very small doses of Botulinum A toxin into the affected muscles is a new and efficient therapy for patients with focal dystonia. The toxin acts by inhibiting the release of acetylcholine from the nerve terminal, leading to a localized paralysis of the treated muscle. The effect is temporary and gradually diminishes, but the treatment can be repeated. The use of Botulinum toxin must be applied on the basis of a thorough knowledge of its effect and possible side effects.
A major problem in epileptology is why a seizure occurs at a particular moment in time. An initial step in solving this problem is a detailed analysis of the temporal distribution of seizures. Using methods and theories of stochastic processes, seizure patterns in a group of epileptic outpatients were examined for stationarity, randomness, dependency and periodicity in a prospective study. Sixteen of the 21 seizure diaries included in the study showed stationarity; 2 were non-stationary and 3 inconclusive. Eleven of the 16 stationary diaries were non-Poisson (P less than 0.005), indicating that in the majority of patients seizures did not occur randomly. The most frequently encountered phenomenon was seizure clustering. Clustering was considered when the diaries fulfilled all three criteria: (1) a positive R-test (P less than 0.001); (2) deviation from the fitted Poisson distribution towards clustering; and (3) the feature of an autoregressive process in the autocorrelogram plot. Dependency between seizure events was demonstrated in 8 of the 16 stationary diaries, computing first order transition probabilities. A detailed analysis of seizure occurrence is a major step towards a better understanding of the mechanisms underlying seizure precipitation. This is exemplified by our finding of a relation between seizure frequency and the menstrual cycle.
Sixteen males, formerly exposed to carbon disulfide (CS2) for at least 10 years (mean 20 years), were administered a neurological examination, cerebral computerized tomography (CT), regional cerebral blood flow (rCBF) examination and neuropsychological examination. The clinical neurological examination revealed abnormalities in 15; cerebral CT showed signs of atrophy in 13; and neuropsychological examination indicated brain organic changes in 13. With the rCBF examination, slight abnormalities were found in 8. The findings indicate that long-term exposure to CS2 involves a risk of developing toxic encephalopathy, demonstrable on both neurological and neuropsychological examination. Furthermore, structural changes in the brain may be demonstrable by cerebral CT.
The P2 latency of the pattern reversal visual evoked response was measured in 11 patients with hereditary motor and sensory neuropathy (HMSN). The P2 latency was inversely related to the peripheral nerve conduction velocity, but no significant relation was found between the P2 latency and the age of the patients or the duration of their symptoms. When the whole group was considered the mean P2 latency was longer but not significantly different from a control group. When the 11 patients were differentiated into HMSN I (5 males) and HMSN II (2 females, 4 males) the P2 latencies of the patients with HMSN I were significantly longer than those with HMSN II. The data support earlier findings that subclinical involvement of the optic nerve may occur in HMSN and suggest that measurement of P2 latency may be of value in the differentiation of HMSN. More than two subtypes, however, may exist.
Six patients (4 females, 2 males) with generalized myasthenia gravis (MG) have been treated in an open study with ciclosporin (5-10 mg/kg/day), originally for 28 weeks. The age of the patients ranged from 16-61 years and the duration of symptoms from 5-30 years. Four of the patients had been thymectomized. Ciclosporin was added to prednisolone in 5 of the patients. Three of these had in addition previously used azathioprine without satisfactory improvement. The efficacy was measured by scoring the degree of muscle weakness on clinical examination and by scoring of the patients' personal assessment of their fatigability and muscle strength. In 5 patients there was a moderate to marked improvement in muscle strength and fatigueability on ciclosporin therapy. In one patient the effect was slight to moderate. The degree of improvement was similar in the one patient who received ciclosporin alone and in those also using prednisolone. The levels of anti ACh-r antibodies decreased in 3 patients, increased in 2, and were unchanged in one patient. Side effects known to occur on ciclosporin therapy were noticed, but they were tolerable in all patients. An increase in serum creatinine (mean 10%) and decrease in creatinine clearance (mean 21%) were seen in all patients. The treatment with ciclosporin has been continued in all 6 patients, but the dosage has been reduced to 5 mg/kg/day. Deterioration 3-4 weeks after discontinuation of ciclosporin was seen in one case, but resumption of therapy resulted in improvement as before. The total treatment period is now 24-34 months (March, 1987).(ABSTRACT TRUNCATED AT 250 WORDS)
We evaluated the feasibility of using the in vitro transverse rat hippocampal slice as a model to study the effect of bilirubin on neuronal activity. Bilirubin in concentrations from 100 mumol/liter to 1 mmol/liter with bovine serum albumin as a stabilizer caused a significant decrease in the slope of the field excitatory postsynaptic potentials, concomitant with a significant increase in the peak latency of the population spike. These changes were partially reversible when bilirubin was removed from the incubation fluid. A partially reversible shift to the right of the presynaptic fiber volley/field excitatory postsynaptic potential relationship was interpreted as an expression of a reduction in synaptic activation. A partially reversible shift to the left of the field exitatory postsynaptic potential population spike relationship was interpreted as an expression of increased postsynaptic excitability. In conclusion the in vitro rat hippocampal slice was used successfully to study the effect of bilirubin on neuronal activity. A depressive effect of bilirubin was observed.
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Serum concentrations of thyroxine, triiodothyronine, TSH and prolactin were measured in 10 patients with affective disorders receiving ECT. Samples were drawn at -15 min, 0, +30 min, +60 min and +3 hr after ECT. A significant increase in both prolactin and TSH was observed 30 min after ECT. A small but significant decrease in triiodothyronine but no change in thyroxine was found in all post-ECT samples. The increase in TSH may be caused by an anti-dopaminergic effect of ECT at either the pituitary or the hypothalamic level.
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There have been very few reports on rhythmic variation in thyroid hormone concentrations with a periodicity of 4-6 weeks. In an attempt to evaluate whether such a rhythm is a general phenomenon we studied ten healthy male students with weekly blood samples over 12 weeks for T4, T3 and TSH. No rhythmicity could be demonstrated.
Two patients with herpes zoster ophthalmicus (HZO) who experienced a delayed contralateral hemiparesis, the so-called crossed zoster syndrome, are described. Particular emphasis is paid to the cerebral blood flow (CBF) findings studied with the Xenon-133 inhalation technique using single photon emission computed tomography (SPECT). In a 40-year-old female with right-sided hemiparesis, angiography showed multiple segmental narrowings of the intracerebral arteries. Cerebral computer tomography (CT) scans were normal. The CBF studied 11 months after the HZO showed a generalized reduction of flow which, however, was more pronounced in the left hemisphere. On re-examination 8 months later both the mean hemispheric flow and regional CBF (rCBF) had increased to normal values. In a 66-year-old male with dysphasia and right-sided hemiparesis, cerebral CT scans demonstrated two small deep left-sided infarcts. CBF examination showed a generalized reduction of flow in the left hemisphere. The flow was slightly increased on re-examination 12 months later. These findings suggest that the Xenon-133 inhalation method represents a useful way to demonstrate the CBF pattern in this group of patients.
A patient with undiagnosed myotonic dystrophy presented in pregnancy with a history of severe obstetric and neonatal complications in her two previous pregnancies. Problems arising after cesarean section led to the diagnosis of myotonic dystrophy. The features of this condition and its implications for pregnancy are pointed out. Complications of pregnancy and parturition may be the first symptoms of myotonic dystrophy.
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