Biomedical subjects

B Mamoli

Publications and source records attributed to B Mamoli.

At least 73 records · Page 4Linked to original sources

PubMed1994

T/A-analysis with or without measuring force: problems in the evaluation of normal limits.

Turn/amplitude-analysis (TAA) has been applied to interference patterns of the right m. biceps brachii and the right m. rectus femoris of 33 healthy women aged 19 to 53 years. Interference patterns were recorded at 20, 40 and 60% +/- 10% of both muscles maximum force. The dependency of the turn/amplitude-parameters (T/A-parameters) on age, muscle and force is discussed. Normal limits for individual means of the T/A-parameters were calculated in form of the +/- 2 SD. Normal limits for single values were calculated in form of clouds. Both methods were applied to the values of each force level (20, 40 and 60%) and of all force levels together (10-70%). Clouds of the present study were clearly different from those of Stålberg. Evaluating individual means rates of false positive results were higher compared to those of single values. Rates of false positive results for single values and individual means of the parameters T/S and A/T were lower at the 20% force level than at the higher force levels and without measuring force. For the application of the TAA we advise every electrophysiological laboratory 1) to evaluate single values instead of individual means, 2) to use clouds instead of the +/- 2 SD as normal limits, 3) to measure force until a modified cloud-method will be applicable and 4) to elaborate its own normal limits.

Adult↗

PubMed1993

[Therapy of epilepsy in the elderly].

The incidence of epileptic seizures is high in childhood, but shows regression during adult life until the age of 65 when there is again a marked, age-dependent increase in frequency. The specific problems of anticonvulsive therapy in the elderly are discussed in the light of the sparse literature on this subject. Pathophysiological influences of aging on the pharmacodynamics and pharmacokinetics of antiepileptic drugs have to be taken into account, such as changes in the renal, hepatic and intestinal functions as well as increased neuronal receptor sensitivity, among other factors. The optimal time to start therapy is controversial. In selecting the antiepileptic drug, particular attention must be paid on cognitive dysfunction and impairment of impulse conduction. Moreover, age-dependent side effects, as well as possible additive effects due to interaction with other medication have to be taken into consideration. In view of the high rate of relapses great caution has to be taken to withdraw the antiepileptic drugs in completion of the therapeutic regimen.

Aged↗

PubMed1992

[Satellite potentials: definition, normal values and validity in the detection of mild myogenic lesions].

From the right m. biceps brachii and the right m. rectus femoris of 28 healthy women aged 19 to 30 years and 16 possible and obligate Duchenne-carriers aged 26 to 40 years we recorded 20 motor unit action potentials each. A satellite potential was defined as electrical activity following or preceding the main component and separated from it by an isoelectrical interval of at least 1, 2 or 3 ms. The most appropriate of these 3 satellite potential definitions is the one that proceeds from a 1 ms minimum interval, because it allows the detection of more satellite potentials than the two others. Applying this definition (minimum interval between the main component and the satellite potential 1 ms) to our controls data we computed a mean interval duration of 5 (m. biceps brachii) respectively 3.4 ms (m. rectus femoris), a mean satellite potential duration of 4.4 (m. biceps brachii) respectively 3.7 ms (m. rectus femoris) and a mean satellite rate of either 3.9 (m. biceps brachii) or 1.6% (m. rectus femoris). We observed up to 3 motor unit action potentials with a satellite potential and up to 1 polyphasic motor unit action potential with a satellite potential per 20 motor unit action potentials. There was little difference between the controls and the Duchenne-carriers satellite parameter means. Only the m. rectus femoris satellite potential duration was increased in Duchenne-carriers.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗

PubMed1992

[A single daily dose with valproic acid. A pharmacodynamic and clinical study].

A prospective clinical pharmacokinetic study was carried out in 10 adult patients with primary or secondary generalized tonic-clonic seizures on the efficacy of valproic acid (VPA) administered as a single daily dose in comparison with divided doses thrice daily. The observation period covered 28 weeks. Without changing the total daily dosage the once-daily treatment proved to be of at least equal clinical efficacy. The single daily dose was well tolerated without any increase in adverse effects. Following a once-daily evening dose the VPA plasma profiled displayed--as expected--a steep increase during the early evening hours, reaching a maximal value around 2 a.m.; afterwards the plasma levels decrease continuously until the next evening. By comparison, the thrice-daily regimen gave maximal VPA levels at 2 p.m. With respect to the pharmacokinetic parameters, the minimum VPA plasma concentrations proved to be significantly lower, and the fluctuations significantly higher during the once-daily administration period the mean maximum VPA plasma level was higher, but not significantly so. The bioavailability was not affected by the change in dosage regimen. Since once-daily evening administration results in better patient compliance it seems appropriate to initiate VPA therapy with this simplified dosage regimen. For patients with inadequate seizure control on multiple daily doses of VPA it seems feasible--from a theoretical point of view--that the rate of attacks might be reduced after a changeover to a once-daily evening dosage regimen, but this has not yet been proven in clinical practice.

Adolescent↗

PubMed1991

[Potential reversal/amplitude analysis: problems of normal value determination].

Turn/amplitude-analysis was applied to the right m. biceps brachii and the right m. rectus femoris of 30 healthy women aged 19 to 39 years. Interference patterns were recorded at 20, 40 and 60% of the individual maximum force of both muscles. We evaluated the turns/s, the amplitude/turn and the ratios amplitude/turns:turns/s and turns/s:amplitude/turn. Normal values of the turn/amplitude-parameter were calculated as means +/- 2 SD at defined levels of force (table 1 and fig. 2) and in form of clouds (fig. 3). Our clouds were clearly different from those of Stalberg. Since normal values of our and other studies were inconsistent we believe that every laboratory has to elaborate its own normal values. Turns/s, amplitude/turn and the ratio turns/s:amplitude/turn increased and the ratio amplitude/turns/s decreased with increasing force (fig. 6 and 7). Turn/amplitude-parameters were partly significantly higher or lower in the m. biceps brachii than in the m. rectus femoris (fig. 8.).

Adult↗

PubMed1991

[Electrophysiological studies in acute Guillain-Barré syndrome].

Based on a synopsis of the literature and our own investigations we discuss the electrophysiological changes in acute Guillain-Barré syndrome. These changes must be viewed in relation to the clinical course of the illness. The SPA evoked by distal stimulation decreases by 50% during the first week of illness, continues decreasing in the second and third weeks and then shows a tendency to normalization. In a similar way, the motor NCV reaches a minimum in the third week and then shows a slow increase again. The motor NCV findings return to normal earlier than SPA. At an early stage we find changes in F-wave and distal latency as well. In connection with the clinical picture, the incidence of changes pointing to a primary demyelinating polyneuropathy can be seen as an electrophysiological sign for the Guillain-Barré syndrome. The relevant criteria are discussed. There are various views concerning the validity of the electrophysiological findings in terms of prognosis of acute Guillain Barré syndrome. Since prognosis is dependent, at first, on the amount of the denervation, the decrease of SPA is of importance. To be able to give a prognosis it is necessary to examine large number of motor nerves electrophysiologically. However, it is very often not possible to make a reliable electrophysiological prognosis in the individual case. The pathophysiological basis for electrophysiological changes in demyelinating PNP's is discussed.

Acute Disease↗

PubMed1989

[The significance of electromyography in detecting myopathies in functional disorders of the thyroid gland].

This paper reviews the value and limits of electrophysiological techniques for the detection of myopathies in disorders of thyroid gland. The electromyographic patterns are described and the pathophysiological mechanisms underlying the myopathies are discussed. The establishment of a relationship between the described electrophysiological patterns and the clinical, morphological and biochemical findings is attempted.

Electromyography↗

PubMed1989

Diffuse cerebrospinal gliomatosis presenting as motor neuron disease for two years.

A patient with symptoms and signs of motor neuron disease for 2 years finally developed sensory disturbances and increased intracranial pressure. MRI and CT showed enlargement of the right side of the cerebellum, the brainstem and parts of the cerebral hemisphere with focal hyperperfusion demonstrated by SPECT. Necropsy revealed a diffuse cerebrospinal gliomatosis with loss of spinal motor neurons in tumour infiltration of the anterior horns. This type of spinal cord involvement is considered responsible for the unusual clinical presentation of the neoplasm.

Adult↗

PubMed1988

[Somatosensory evoked potentials following tibial nerve stimulation. Method and normal values in relation to physical variables].

Somatosensory evoked potentials were recorded in 40 healthy subjects (age: 22-63 years) with gluteal, lumbar, cervical and cortical surface electrodes after stimulation of the tibial nerve. Normal latency values were established in relationship to height and also for the amplitudes of the different components; the latencies of the cortical P40, N50 and P60 were significantly dependent on height, the latency of the cervical N33, the lumbar N22 and the gluteal Ng were dependent on the distance (stimulation--to recording point). The central conduction time showed no dependence on back length. Age dependence (in relation to normal height) was found only in the case of cortical P60.

Adult↗

PubMed1988

Hexa-methyl-propylene-amine-oxime (HMPAO) single photon emission computed tomography (SPECT) in epilepsy.

Twenty-eight normal volunteers and 74 seizure patients were investigated with hexa-methyl-propylene-amine-oxime (HMPAO) brain single photon emission computed tomography (SPECT). Fifty-four patients suffered from partial seizures and 20 patients had generalized seizures. Indices describing regional tracer distribution (RIs) were calculated in all investigated subjects. Regions whose RI exceeded the mean normal RI +/- 3 SD were defined as abnormally perfused. In normals a significant interhemispheric asymmetry of HMPAO deposition was found, with higher RI values in the right frontal, parietal, temporal and occipital regions. In 59.3% of partial seizure patients abnormal RIs were found. Low RIs were detected predominantly in the frontal and temporal cortex, while elevated RIs were observed predominantly in the anterior basal ganglia. Only in 20% of the cases with generalized seizures, abnormal RIs were found. In one patient an ictal and 3 follow-up SPECT studies were obtained. Here SPECT results indicated transient rCBF changes between the ictal and seizure free state. EEG and SPECT foci were ipsilaterally located in 69.2% of the partial seizure cases. The results indicate that HMPAO brain SPECT is valuable for the detection of rCBF abnormalities in seizure patients and that patients with partial seizures have mostly several abnormally perfused areas in their brains.

Adult↗

PubMed1987

Influence of television on photosensitive epileptics.

We examined 32 epileptics (20 female; 12 male; aged 6-73 years) who had displayed photoconvulsive reactions to flickering light in the EEG; they were examined with regard to their risks of getting epileptic seizures upon watching television (TV) under certain conditions. On a colour TV set each patient was shown a 3-min videofilm with slow- and fast-moving parts under 16 different conditions. The conditions had the following variables: (1) colour - monochrome; (2) dark room - light room, and (3) four different distances from the screen. In addition, each patient was subjected for 3 min to manipulated image interferences, including the vertical rolling of the picture. The results of this TV stimulation were always negative, i.e. in no patient did TV provoke a reproducible paroxysmal discharge in the EEG, nor was there any epileptic seizure. Our findings are discussed in connection with the corresponding literature.

Adolescent↗

PubMed1986

[Value of acetylcholine receptor antibodies in myasthenia gravis].

In a retrospective study in 47 patients with myasthenia gravis acetylcholine-receptor-antibody-titers (AChR-AB) were correlated with the severity of the disease. In 18 patients the course of titers was studied and two groups of patients could be differentiated: patients with relative constant and patients with fluctuating titers. Age, age of begin of myasthenia and sex did not influence the titers. Also the duration of the disease and the severity of symptoms did not influence the level of AChR-AB-titers. In this retrospective study the influence of immun-suppressive therapy on the intra-individual course of AB-titers and their correlation with the clinical symptoms could not be judged. Measurement of AChR-AB is of value for the diagnosis of myasthenia gravis and important for judging the clinical course and the effect of therapy.

Adult↗

PubMed1986

[Sensorimotor and autonomous polyneuropathies in diabetic children and adolescents].

In 28 juvenile and adolescent diabetics (14 males, 14 females) ranging in age between 9 and 20 years (mean: 14.9) we investigated several electrophysiological parameters, the vibration threshold and the cardiovascular reflexes in order to determine the incidence of sensomotor and autonomic polyneuropathy. 6 patients showed evidence of sensomotor polyneuropathy, 2 more had signs of autonomic polyneuropathy. Both groups with polyneuropathy did not differ significantly from the whole group of diabetics concerning the mean onset of illness and several metabolic parameters. The mean duration of illness and the average age was clearly higher in the patients with sensomotor polyneuropathy than in the whole group. Out of 5 patients with diabetic retinopathy 3 had signs of sensomotor polyneuropathy. No patient was clinically affected by polyneuropathy. In 1 patient the distal latency and the amplitude of the compound muscle action potential of the peroneal nerve showed pathologic values, in a second patient the maximal conduction velocity of the median nerve was slowed. 4 patients had abnormally high vibration threshold. The heart rate variation during rest was reduced in 2 patients. Significant differences between the diabetics and the controls could only be found concerning the maximum conduction velocities of the peroneal and the median nerve. Our results will be compared and discussed.

Adolescent↗

PubMed1986

[Changes in brain stem potentials in dystrophia myotonica].

In 15 patients with dystrophia myotonica brainstem auditory potentials (BAEP) were examined: in 8 patients (53%) pathological components in the BAEP's (such as increased latency of one peak) and in 80% a pathologic component in the neurography could be found. Comparing the latencies of the peak and the interwave latencies in the patients' and control group there was no significant difference. Hearing disturbances influenced the latencies of the first BAEP-component, increased triglycerides correlated with pathologic nerve conduction velocity and singular pathologic BAEP values correlated with abnormal neurographic parameters. All these correlations emphasize the complexity of alterations in dystrophia myotonica.

Adult↗

PubMed1986

[Neurophysiologic studies in Pickwickian syndrome].

In 11 patients clinically diagnosed as Pickwickian syndrome the results of daytime and night polysomnogramm were compared. The daytime recording was very efficient in identifying apnoea and correlating various types of apnoea to different sleep stages. In polysomnogramms of night sleep we found, as did Lugaresi, a reduction of sleep stages III and IV, and a slight increase of sleep stages I and II. Patients without apnea in daytime sleep also showed a normal apnea index in night sleep. The BAEP's especially the pontomesencephalic components were pathological in six patients (55%). This might be due to a primary lesion or to hypoxic damage of the brainstem.

Adult↗

PubMed1986

[A procedure for the determination of spinal cord length in vivo].

Using anthropological methods, we measured the body height, length of the spine (ventral and dorsal), leg length, cord length. The data were evaluated statistically and we looked for correlation between leg length and body height, cord length and length of the spine, length of the spine and body height. On the basis of our results, we were able to determine the cord length for clinical use by computing the regression coefficient of leg length and spinal length.

Adult↗

PubMed1985

[Diagnosis of myasthenia. Value of tensilon test, repetitive stimulation, staircase phenomenon and acetylcholine receptor antibody titer].

In a retrospective study on 78 patients with myasthenia gravis the diagnostic value of various investigational methods is assessed. On the basis of the results of the Tensilon test, repetitive stimulation, the staircase phenomenon and acetylcholine receptor antibody titre in the different clinical subgroups practical guidelines are proposed for the diagnosis of myasthenia gravis.

Antibodies↗

PubMed1985

[Acute myelomonocytic and monoblastic leukemia with polyradicular symptoms].

Meningeal leukaemia, developed in 4 female patients with M4 or M5 leukaemia during a period of haematological remission. Polyradicular symptoms and signs dominated neurologically, but 3 patients also exhibited cranial nerve palsies. The neurological findings showed no reversal following intrathecal chemotherapy with normalization of liquor cytology. Patchy demyelinization in the region of the anterior spinal roots and of the proximal segments of the affected cranial nerves were responsible for the neurological features. Peripherally located streaky demyelinization of the olfactory bulb and of the optic chiasm were not found to cause any neurological manifestations.

Abducens Nerve↗