Biomedical subjects

E Matikainen

Publications and source records attributed to E Matikainen.

17 recordsLinked to original sources

PubMed1992

Sustained high plasma 5-aminolaevulinic acid concentration in a volunteer: no porphyric symptoms.

The pathogenesis of the acute porphyric attack is not known. One hypothesis is that porphyrin precursors, especially 5-aminolaevulinic acid (ALA), are toxic for neuronal tissue. This was tested by infusing ALA in a male volunteer after a loading dose at a rate of 50-80 mg h-1 for 92.5 h. During the experiment plasma ALA concentration was 9-11 mumol 1-l and porphobilinogen concentration 3-6 mumol 1-l which are the levels seen during acute attacks. Urinary excretion of these porphyrin precursors was also markedly increased. ALA infusion caused no subjective symptoms and no change in pulse rate, blood pressure, or autonomic nerve function or conduction velocity of peripheral nerves. Photosensitivity was not demonstrable. It is concluded that sustained high plasma ALA concentration does not cause porphyria-like symptoms.

Aminolevulinic Acid↗

PubMed1992

Metabolic control and progression of complications in insulin-dependent diabetic patients after kidney transplantation.

Patient survival and progression of complications were monitored for 3 years after kidney transplantation in 29 type-1 diabetic patients. Ten age-matched, non-diabetic kidney-transplanted patients served as controls. Five diabetic patients died during follow-up (three cardiovascular events, two infections), three diabetic patients had a non-fatal myocardial infarction and four developed cerebrovascular complications after transplantation. Of the diabetic patients, 69% suffered from proliferative retinopathy before transplantation; 20% of them improved, 65% remained unchanged and 15% deteriorated after transplantation. Motor but not sensory conduction velocity measured from the nervus medianus improved after transplantation. Autonomic neuropathy was observed in 50% of the patients and was unaffected by transplantation. Glycaemic control did not improve significantly during follow-up (HbA1, 10.6 +/- 0.5% before and 9.5 +/- 0.6% 3 years after transplantation). Body weight increased in both diabetic and non-diabetic patients within 3 years after transplantation (from 68 +/- 2 to 77 +/- 6 kg in diabetics, P less than 0.01; from 167 +/- 4 to 77 +/- 6 kg in non-diabetics, P less than 0.01). Subcutaneous fat thickness measured from computer tomography scans of the calf increased in diabetic patients from 5.0 +/- 0.6 to 6.1 +/- 0.9 mm (P less than 0.05). However, the cross-sectional areas of triceps and calf muscles did not increase, suggesting that the increase in body weight was solely due to an increase in fat. It is clear that diabetes-related complications continue to progress and are not influenced by a successful kidney transplant.

Adult↗

PubMed1990

Vibration sensitivity thresholds: methodological considerations.

Vibration sensitivity thresholds were studied in 12 healthy volunteers using 25, 50, 100 and 250 s-1 stimulus frequencies from an instrument with automated and manual modes ('Vibra Mk II'). For the automated mode, a forced choice principle was adopted. All measurements were performed from both the knuckle of the IInd metacarpophalangeal joint and the medial malleolus on four successive days. In addition, a conventional tuning fork method for vibration sensitivity was applied. The results show high interindividual and intraindividual variation in all measurements. The threshold values measured by the automated system were significantly lower than those by manual system at all frequencies. The largest variation was seen at 250 s-1 and the most uniform values at 100 s-1. There was a clear difference between the values from knuckle and medial malleolus, the values in the foot being lower. There was no learning effect. Clear age-related increase in vibration thresholds was observed. Conventional tuning fork-method showed clear differences in vibration sensitivity between hand and foot, in accordance with computer assisted method. The higher sensitivity of the automated method compared to the manual makes this the method of choice, although further investigations to finish the method and to build up a broader reference material is desirable.

Adult↗

PubMed1989

Occupational exposure to solvents and cerebellar, brainstem and vestibular functions.

Forty-eight persons (age 44, SD 9 years) exposed to paint solvents and 40 nonexposed referents (age 45, SD 9 years) were examined. The duration of exposure was 4 to 30 (mean 20) years and the life-time exposure level was estimated to have been 10 to 330 (mean 60%) of the hygienic standard. The methods used were a neurological examination, electroencephalography, brainstem auditory-evoked potentials, electronystagmography, and posturography. Life-time exposure was estimated on the basis of a detailed occupational history and environmental measurements made at the work places over several years. The average weekly alcohol consumption was established in a detailed interview. Due to the small number of subjects examined, the study was inconclusive. The findings classified as abnormal were slightly more common in the exposed than in the referents, and in the persons who used alcohol than in the non-users. The differences were not statistically significant, and no exposure-response relationships were found.

Adult↗

PubMed1989

Posturography and the dizzy patient: a neurological study of 133 patients.

A total of 133 dizzy patients under the age of 60 years were examined using a stable balance plate (posturography, PG). All the patients were thoroughly examined neurologically before PG and classified into 7 diagnostic categories. Comparison was made between these categories and PG results. The referent group consisted of 116 healthy individuals. The patients with CNS lesions had more body sway than controls or the patients with peripheral vestibular lesions, whose sway did not significantly differ from that of the controls. The PG parameters that most clearly separated the patients from the controls were the total length of the movement of the center of gravity, and the sway in lateral and antero-posterior directions. Analysis of the frequency of the sway or calculation of the Romberg index did not reveal significant differences between the categories. Men swayed more than women. Age did not correlate with PG results. Stable posturography offers useful quantitative supplementary information as a part of the examination of a dizzy patient. Increased body sway suggests a lesion in the CNS.

Adolescent↗

PubMed1988

Diagnostic value of electroencephalography and brainstem auditory evoked potentials in dizziness.

Electroencephalogram (EEG) and brainstem auditory evoked potentials (BAEP) were recorded from 142 dizzy patients. The results were compared with those obtained by other neurological examinations of the same patients. Thirty-three percent (N = 44) of the patients had an abnormal EEG: 21% (28) showed focal abnormality, 12% (16) irritative features, and 10% (13) generalized disturbance. There were no differences in the distribution of abnormal EEGs in different diagnostic categories of dizziness, but irritative findings were not found in the cases of peripheral vestibular or psychogenic disturbances. EEG findings in 3 patients suggested temporal epilepsy, correlating with the clinical picture. BAEPs were abnormal in 18% (N = 21) of the recordings. There were 3 cases of MS and 5 ischaemic lesions in the vertebro-basilar region. Twelve of the 13 other patients with abnormal BAEP showed evidence of CNS pathology with other methods. EEG abnormalities were mostly non-specific; however, the irritative findings suggested cerebral pathology, such as epilepsy. An abnormal BAEP offers reliable evidence for brainstem lesion and is thus a useful examination in dizziness.

Adolescent↗

PubMed1988

HLA-antigens and immunity to insulin in insulin-dependent diabetics with or without diabetic neuropathy.

In order to define genetic, immunological and metabolic risk factors and markers associated with diabetic neuropathy (DN) 47 insulin-dependent diabetic patients with neuropathy were compared to 30 age-matched insulin-dependent diabetes mellitus (IDDM) patients without neuropathy. Patients with diabetic neuropathy more often had proliferative retinopathy and Albustix positive proteinuria than patients without neuropathy. Judged by haemoglobin A1 (HbA1) concentrations measured during the preceding two years glycaemic control was worse in patients with than without diabetic neuropathy. The frequency of HLA-antigens DR3, DR4, DR3/DR4, B8, and B15 were increased and those of DR2 and B7 decreased in the diabetic patients. The frequency of any of these HLA-antigens did not differ in patients with or without diabetic neuropathy. There were no significant differences in the frequencies of insulin antibodies or proliferative responses to insulin antigens between patients with or without diabetic neuropathy. However, patients who were HLA-DR3/DR4 heterozygotes and had diabetic neuropathy responded to insulin antigens more often by proliferation than DR3/DR4 positive patients without diabetic neuropathy. Thus poor glycaemic control is associated with an increased risk for diabetic neuropathy. Patients with DR3/DR4 heterozygocity and failing to respond to insulin antigens by proliferation seem to be less prone to develop diabetic neuropathy.

Adult↗

PubMed1988

Peripheral nerve injury and Raynaud's syndrome following electric shock.

A truck driver was injured by a high-voltage line of 10,000 volts when holding a metallic bar in both hands. Initially no neurological abnormalities were found, but during the following few weeks increasing sensory and minor motor symptoms developed in the right upper extremity. After one year numbness of the right thigh and leg appeared, as well as attacks of white finger in both hands. Repeated examinations showed progressive abnormalities of the median and ulnar nerves in both hands. No other cause for Raynaud's syndrome was discovered. The late high-voltage effects, presumably indirect, are suggested to be of multifactorial etiology.

Adult↗

PubMed1987

Postural body sway and exposure to high-energy impulse noise.

Detailed neurological and audiological examinations and body-sway measurements with a stable platform were carried out on 60 subjects who had been exposed to high-energy intermittent noise from firearms and had various degrees of noise-induced hearing loss. The results were compared with those for 115 healthy controls. The exposed subjects showed significantly more body sway, estimated as movement of the centre of gravity in the horizontal plane, than the controls. This swaying correlated poorly with the recalled level of noise exposure, though subjects with more severe hearing loss (by audiometric deterioration of high-frequency sound, 4 kHz and 6 kHz) showed more sway than those with less severe hearing loss. Age was not significantly correlated with body sway among the controls but men seemed to sway more than women. These results suggest subclinical disturbance of the vestibular system among subjects with impulse-noise-induced hearing loss.

Adult↗

PubMed1987

The effect of exposure to high and low frequency hand-arm vibration on finger systolic pressure.

Twenty-three patients with hand-arm vibration exposure and diagnosed vibration syndrome were given a thorough clinical and neurophysiological examination, together with finger strain gauge plethysmography. Eleven of the patients were forest workers regularly using chain saws (low frequency vibration exposure), and twelve were metal grinders (higher frequency vibration exposure). Both groups had significantly lower finger blood pressures than healthy controls, and comparisons between the groups indicated that the mean values tended to be lower in the grinders. The findings suggest that hand-arm vibration exposure is associated with obstructive changes in the distal arteries of the fingers, and that vibration frequency is one of the factors determining the severity of the changes and the time of onset of the symptoms.

Adult↗

PubMed1987

Cardiovascular reflexes in monozygotic twins discordant for exposure to organic solvents.

Eighteen pairs of monozygotic twins discordant for long-term occupational exposure to organic solvents were examined for disturbances of cardiovascular reflexes. All of the subjects were asymptomatic, and considered themselves healthy. No significant differences were observed between the exposed and the nonexposed twins. The finding suggests that occupational solvent exposure at these particular levels is unlikely to cause disturbances of the autonomic nervous function.

Adult↗

PubMed1986

Risk factors and markers associated with proliferative retinopathy in patients with insulin-dependent diabetes.

To define risk factors and markers associated with proliferative retinopathy (PR), we compared 44 insulin-dependent diabetic patients with PR with 45 matched patients without advanced retinopathy (NR). Glycemic control assessed by HbA1 measurements from 5 yr preceding diagnosis of PR was significantly worse than in NR patients. The NR patients had more frequently been treated with multiple daily insulin injections than the PR patients. About half of the PR patients had Albustix-positive proteinuria, and these patients were further characterized by an abnormal lipid profile in plasma and increased frequency of cardiovascular disease. In contrast, PR patients without proteinuria did not differ from NR patients in these variables. Sensorimotor and autonomic neuropathy were twice as frequent in the PR than in the NR group. There was no correlation between anti-insulin antibody titer, immune complexes, and the presence of PR, but T-lymphocyte response to different stimuli was slightly reduced in the PR patients. The anti-insulin-antibody titer correlated with duration of diabetes in the NR but not the PR group. The frequency of HLA-DRw8 was slightly higher in the PR group than in the NR group (16 vs. 0%, NS), but we could not confirm the previously suggested association between HLA-DR4 and PR. Serum C4 levels were low in the diabetics but did not differ between PR patients without proteinuria and NR patients. In conclusion, poor glycemic control was clearly associated with PR in this study, and attempts to prevent this hazardous complication should include means to improve insulin therapy. We did not find support for the view that susceptibility to PR is associated with any known HLA antigen(s).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1986

Autonomic dysfunction in long-standing alcoholism.

Twenty-eight male alcoholics were studied for peripheral sensory-motor and autonomic neuropathy. The patients were examined neurologically and neurophysiologically after a period of withdrawal treatment in hospital. The function tests of the autonomic nervous system performed were: measurement of the variation of the heart rate at rest and during maximal breathing, Valsalva manoeuvre, postural pulse and blood pressure reactions, and isometric test. Slight abnormalities in the peripheral nervous system were observed in 8 patients, but a frank clinical polyneuropathy supported by neurophysiological findings could be diagnosed only in 2. All of the parameters which reflect the function of the parasympathetic division of the autonomic nervous system were lower in the alcoholics compared with the controls. The most sensitive variables were the heart rate variation at rest, and the postural pulse reaction. The functions mediated by the sympathetic nervous system were not abnormal among this group of alcoholics.

Adult↗

PubMed1985

Occupational exposure to toluene: neurotoxic effects with special emphasis on drinking habits.

Neurotoxic effects of toluene were examined in 43 male rotogravure printers exposed to toluene (age 27-63, mean 41 years; duration of exposure 11-40, mean 22 years) and 31 male offset printers of the same age with slight exposure to aliphatic hydrocarbons. A neurological examination, tests for autonomic nervous function, electroencephalography, psychological tests and computerized tomography of the brain were carried out in addition to a standardized interview. Exposure levels were evaluated for each person separately on the basis of his work history and the results of an earlier study on exposure levels at the same printing shops. Besides a thorough history of alcohol consumption, information about the printers' drinking habits was obtained from the occupational health care centers of the printing shops. The examinations found only slight abnormalities, and there were no statistically significant group differences in the prevalences of abnormalities. No correlations between the abnormalities and the exposure indices were found either. One of the retired workers, however, who had been exposed to high toluene concentrations for over 40 years, had been diagnosed as having chronic organic solvent intoxication. Heavy drinkers of alcohol were clearly more common in the toluene-exposed group. This study detected no clinically significant abnormalities attributable to toluene alone among workers exposed to 68-185 ppm (mean 117) of toluene for over 10 years. The connection between alcohol consumption and toluene exposure is interesting and deserves further study.

Adult↗

PubMed1985

Nervous system effects of long-term occupational exposure to toluene.

Forty-three male rotogravure printers with long-term toluene exposure and 31 age- and sex-matched offset printers without toluene exposure were examined in detail. Clinical, neurophysiological, neuropsychological and neuroradiological examinations and assessment of autonomic functions did not reveal any statistically significant differences between the groups. The results suggest that occupational long-term exposure to toluene under these circumstances does not have clinically significant adverse effects on the nervous system. Exposure to toluene seemed to be associated with heavy drinking.

Adult↗

PubMed1985

Autonomic nervous system dysfunction in workers exposed to organic solvents.

Tests for cardiovascular function were made in 34 workers exposed to organic solvents for several years (mean 16.2 years). The results were compared with those of 52 healthy subjects. All the cardiovascular parameters were lower in the exposed group. The exposed subjects with evidence of peripheral neuropathy had lower values than those without neuropathy. The findings suggest that peripheral parasympathetic nerves may also be involved in mild sensory-motor peripheral neuropathy among subjects with long-term occupational exposure to organic solvents.

Adult↗

PubMedDate not supplied

Subclinical vestibular pathology in patients with noise-induced hearing loss from intense impulse noise.

Sixty patients with varying degrees of noise-induced hearing loss (NIHL) after long-term exposure to intense impulse noise from firearms, but without manifest clinical symptoms of vestibular pathology, were tested for body sway using a stable platform. The results were compared with those from 115 healthy referents examined in the same way. Subjects with NIHL showed significantly more body sway, estimated as movement of the centre of gravity in the horizontal plane, than did the referents. Subjects with more severe NIHL showed more sway than subjects with milder acoustic trauma. The results show that body sway is increased in patients with NIHL from exposure to impulse noise of high intensity in a way suggesting an exposure-effect relationship. This suggests subclinical disturbances of the vestibular system in these patients. The underlying mechanism may be simultaneous mechanical damage to both the cochlear and vestibular partitions by intense impulse noise.

Firearms↗