Biomedical subjects

E F Vuurman

Publications and source records attributed to E F Vuurman.

7 recordsLinked to original sources

PubMed2000

Cognitive dysfunctions and white matter lesions in patients with bipolar disorder in remission.

OBJECTIVE: To compare cognitive functioning in relation to white matter lesions in bipolar disorder in remission and schizophrenia. METHOD: Cognitive performance and the occurrence of white matter lesions on MRI images of the brain were assessed in 22 patients with bipolar disorder in remission, 22 patients with schizophrenia and 22 healthy volunteers. RESULTS: Performance of tests of memory, speed and cognitive flexibility was significantly impaired in both patient groups. The frequency of white matter lesions did not differ significantly between the three groups. No differences in cognitive performance were found between patients with white matter lesions and patients without such lesions. CONCLUSION: White matter lesions apparently do not underlie cognitive deficits that are found in patients with bipolar disorder in remission and in patients with schizophrenia.

Bipolar Disorder↗

PubMed1999

A controlled study of temporal lobe structure volumes and P300 responses in schizophrenic patients with persistent auditory hallucinations.

Recent studies of cerebral pathology in patients with schizophrenia have focused on symptomatological and electrophysiological correlates of reduced temporal lobe structure volumes. Volume deficits of the left superior temporal gyrus have been correlated with auditory hallucinations as well as to left-sided P300 amplitude reduction. However, caution is needed to interpret correlational data as evidence of a specific relationship. Therefore, a controlled study was undertaken on schizophrenic patients with and without auditory hallucinations. MRI-defined volumes of the left superior temporal gyrus and other temporal lobe structures were quantified from 3-mm coronal slices in 15 schizophrenic patients with chronic auditory hallucinations (hallucinators), 15 schizophrenic patients without auditory hallucinations (nonhallucinators) and 17 healthy controls. In all subjects a simple oddball paradigm was used to elicit P300 responses at temporal and centro-parietal electrode sites. No evidence was found for volume reductions of temporal lobe structures in the combined patient group compared with controls, or in the hallucinators compared with the nonhallucinators. The patients did show left P300 amplitude reduction compared with controls, particularly in the hallucinator group. Correlations between volumes of left temporal lobe structures and left P300 amplitudes were low and not significant. The results of the present study do not indicate that auditory hallucinations and associated abnormal electrophysiological activity are the consequence of atrophy of localized temporal lobe structures. However, replication in a larger sample of subjects is needed before firm conclusions can be drawn.

Adult↗

PubMed1996

Effects of mefloquine alone and with alcohol on psychomotor and driving performance.

OBJECTIVE: To determine whether mefloquine, a quinoline antimalarial drug, affects psychomotor and actual driving performance when given in prophylactic regimen, alone or in combination with alcohol. METHODS: Forty male and female volunteers were randomly assigned in equal numbers to two groups, and were treated double-blind for one month with mefloquine and placebo. The medication was taken in a 250 mg dose on the evenings of Days 1, 2, 3, 8, 15, 22 and 29. Testing was done on Days 4, 23 and 30, the latter after repeated doses of alcohol sufficient to sustain a blood concentration of about 0.35 mg.ml-1. Two real driving tests were used to measure prolonged (1 h) road tracking and car following performance. Critical Flicker/Fusion Frequency (CFF), critical instability tracking and body sway were also measured in the laboratory. RESULTS: Mefloquine caused no significant impairment in any test at any time relative to placebo. It significantly improved road tracking performance on Day 4. A significant interaction between prior treatment and alcohol was found in the body sway test, as the alcohol-induced change was less after mefloquine than placebo. The sensitivity of the driving test and the CFF test were shown by the significant overall effect of alcohol which did not discriminate between the two prior treatments. CONCLUSION: Mefloquine did not impair driving performance but rather improved it in the longer test, suggesting that the drug may possess psychostimulating properties.

Adult↗

PubMed1996

Effects of semprex-D and diphenhydramine on learning in young adults with seasonal allergic rhinitis.

OBJECTIVES: The purpose of this study was to test the hypothesis that learning ability is impaired in patients with seasonal allergic rhinitis relative to untreated individuals and to evaluate a combination compound (acrivastine 8 mg + pseudoephedrine 60 mg) for attenuation of the learning impairment in these patients. BACKGROUND: In a previous study employing the same method it was shown that young children (10 to 12 yrs) suffering from seasonal allergic rhinitis performed significantly worse on tests of learning and using knowledge after acute treatment with a sedating antihistamine (diphenhydramine 50 mg) or placebo as compared with nontreated healthy controls. This effect was partially reversed by treatment with loratadine. METHODS: Sixty-seven young adults suffering from seasonal allergic rhinitis and 28 matched controls were trained on didactic simulation for three consecutive days. Atopic subjects were treated differentially during training according to a double-blind, randomized, parallel group design with either diphenhydramine hydrochloride 50 mg, a combination compound (acrivastine 8 mg + pseudoephedrine 60 mg, A + P), or placebo, administered qd. After training, all atopic subjects were maintained on A + P treatment for 14 days at which time all groups returned for examination. RESULTS: Mean performance at the end of training was worse for all atopic subjects combined compared with normal subjects. Subjects treated with diphenhydramine performed significantly worse than either normals (P < .001) or those treated with A + P (P < .001). At the examination, the diphenhydramine group's performance differed significantly from those of the normal (P < .001) and A + P groups (P < .001). CONCLUSION: The study supports our previous finding that allergy symptoms reduce learning ability which is further reduced learning ability which is further reduced by diphenhydramine. Atopic subjects with allergies treated with acrivastine + pseudoephedrine learned as well as normal subjects.

Adolescent↗

PubMed1994

Effects of mizolastine and clemastine on actual driving and psychomotor performance in healthy volunteers.

The acute effect of doses of mizolastine 5, 10, 20 and 40 mg, an active control (clemastine 2 mg) and placebo on actual car driving and psychomotor performance have been compared. Twenty four healthy volunteers were treated according to a double-blind, 6-way cross-over design. In the driving test, lasting about 1 h, lateral position control and speed were continuously measured; the psychomotor test battery, lasting 50 min, comprised critical flicker-fusion frequency, critical instability tracking, divided attention, memory search and choice reaction time, and vigilance studies; and mood changes and possible adverse-effects were rated on visual analogue scales. The results showed a dose-response relationship: mizolastine 40 and 20 mg impaired driving and psychomotor performance. The effect of mizolastine 40 mg on driving was strongly correlated with that of clemastine (r = 0.78) and was comparable to the effect of a blood ethanol level of 0.8 mg.ml-1. Mizolastine 5 mg and 10 mg did not have a significant effect on driving performance and psychomotor tests. It was concluded that at a 10 mg dose of mizolastine, the therapeutic dose, it could be considered a safe anti-histamine, although individual adverse reactions cannot be completely ruled out.

Adult↗

PubMed1993

Seasonal allergic rhinitis and antihistamine effects on children's learning.

Children suffering from seasonal allergic rhinitis and matched normals were instructed on the use of a didactic computer simulation in a realistic classroom situation. Groups of atopic children received different treatments before instruction; ie, sedating (diphenylhydramine HCl) or nonsedating (loratadine) antihistamines or placebo. All returned after 2 weeks for an examination measuring factual and conceptual knowledge and the application of a learned strategy. Examination results showed large and consistent impairing effects of the allergic reaction on prior learning. Both the placebo and diphenhydramine groups learned significantly less than normal controls. The loratadine group's learning performance was superior to either of the other atopic groups' but still inferior to the normals'. Our conclusions are that the allergic reaction reduces learning ability in children and that this effect is partially counteracted by treatment with loratadine and aggravated by diphenhydramine.

Child↗

PubMed1991

Compensatory muscle activity for sitting posture during upper extremity task performance in paraplegic persons.

Compensation for the loss of postural activity of the erector spinae (ES) muscle in spinal cord injured (SCI) subjects was investigated. All SCI subjects had clinically complete lesions below the T3 level. Body disbalance was invoked by requiring sitting subjects to execute reaching movements over individually predetermined distances in a horizontal plane. Myoelectric activity of the latissimus dorsi (LD) muscle and the trapezius pars ascendens (TPA) muscle both in the SCI subjects and in controls was recorded. The body disbalance was measured in terms of changes in the position of the body centre of gravity. The effects of anticipation for body displacement were examined by cuing the direction of the reaching movement. Our results indicate that paraplegic subjects use both LD and TPA to stabilize their sitting posture, in contrast to non-disabled persons. Secondly, the movement anticipation is in general slower in persons with paraplegia. Furthermore, the paraplegic subjects showed considerable impairments concerning the processing of precued information prior to a goal-directed upper extremity movement.

Adolescent↗