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D Devos

Publications and source records attributed to D Devos.

25 records · Page 2Linked to original sources
PubMed2000

[Thulium laser evoked potentials. Normative values for the arms and legs].

Laser somatosensory evoked potentials (LSEP) evaluate the functional integrity of thermoalgic pathways by the specific stimulation of A delta and C nociceptive afferences. As compared to a CO2 laser, the thulium Yttrium Aluminium Garnet (YAG) laser may be conducted by an optic fiber, which allows easier access to the stimulated body sites. We present normative data on thulium YAG LSEPs recorded after stimulation of upper and lower limbs (N = 15). LSEPs were obtained with a stimulation intensity that was twice the nociceptive threshold at the upper limbs (UL) and one and a half at the lower limbs (LL). To ensure a stable attentional level, subjects were asked to estimate stimulus intensity after each stimulation. The nociceptive thresholds at upper and lower limbs were respectively 319 +/- 65 mJ and 359 +/- 95, and with the above methodology the LSEPs could be obtained in every subject. The latencies of N2 and P2 were respectively 199 +/- 18 ms and 325 +/- 37 ms at the UL, 239 +/- 36 ms and 378 +/- 38 ms at the LL. This method produced robust and reproducible results and proved to be reliable for routine clinical use. To optimise response stability we propose that right/left stimulation be conducted following an 'A-B-B-A' procedure.

Adult↗
PubMed2000

Brief and sustained movements: differences in event-related (de)synchronization (ERD/ERS) patterns.

OBJECTIVE: (1) To determine if there are changes in event-related desynchronization/event-related synchronization (ERD/ERS) patterns when the movement is sustained? (2) To determine, from a technical point of view for ERD calculation, if it is possible to take the reference period during muscular activation? METHODS: Eight healthy subjects performed two series of brief and sustained self-paced extensions with their dominant wrist. The end of the sustained movement was externally triggered by the examinator. ERD/ERS was calculated in mu and beta bands from 13 source derivations covering motor areas, computed from 29 scalp electrodes. Movement onset and offset were determined by electromyographic activity (EMG) of wrist extensors. RESULTS: When the movement was sustained, power in the mu and beta bands returned to baseline values within 4-5 s. Movement duration had little effect, if at all, on both pre and post-movement periods. Compared to brief movement, after the onset of the prolonged movement, mu ERD just returned to baseline, without synchronization. In contrast, beta ERS was still present though earlier and much lower. CONCLUSIONS: The reference period for ERD calculation may be taken during muscular activation if its duration is long enough. Beta synchronization may occur despite a non-deactivated motor cortex, suggesting a contribution from afferent somesthetic inputs.

Cortical Synchronization↗
PubMed1998

[Traumatic bilateral paralysis of the abducens nerve without cervical fracture].

We report the case of a 75-year-old woman with an uneventful medical history who presented with sudden-onset diplopia immediately after neck trauma in a traffic accident. Clinical and ophthalmological examinations were consistent with bilateral abducens nerve palsy. The causal relationship, including the medicolegal implications and the pathophysiological mechanism are discussed. The case demonstrates that exceptionally benign trauma can cause severe diplopia. The delay to recovery may be very long, suggesting caution concerning the decision of surgical care.

Abducens Nerve Injury↗
PubMed1997

ANOLEA: a www server to assess protein structures.

ANOLEA (Atomic Non-Local Environment Assessment) is a www server that performs energy calculations at the atomic level in protein structures. The calculations involve the non-local interactions between all the heavy atoms of the twenty standard amino acids in the molecule. The input of the server is a PDB file containing one or more protein chains. The output is an energy profile, which gives an energy value for each amino acid of the protein. High energy zones (HEZs) in the profile correlate with errors or with potential interacting zones of proteins. The output of the server also displays the structure in three dimensions, pointing out the high energy amino acids in the protein. This option requires the CHIME plug-in, which is freely available on Internet and makes possible, in real time, to rotate, translate and change the point of view and presentation of the molecule in three dimensions. Thus, a fast analysis of a protein structure can be done using a personal computer connected to Internet. The server is available at: http:@www.fundp.ac.be/pub/ANOLEA.html.

Amino Acids↗
PubMedDate not supplied

Study of circadian melatonin secretion pattern at different stages of Parkinson's disease.

To explore changes in melatonin secretion patterns and biologic rhythms in Parkinson's disease patients with or without levodopa-related motor complications (LDRMCs), the authors investigated, in an observational study, circadian rhythms of central temperature, motor activity, plasma cortisol, and melatonin in three groups: de novo untreated patients (group I), patients treated with levodopa + dopamine agonist and without LDRMCs (group II), and patients treated with levodopa + dopamine agonist and with LDRMCs (group III). There were no differences among the three groups for the rhythm of temperature, motor activity, or plasma cortisol. There was a significant (p < 0.05) phase advance in plasma melatonin secretion in patients receiving a dopaminergic treatment compared with untreated patients. The daytime area under the curve (AUC) was increased significantly in group III, and the nighttime AUC-to-daytime AUC ratio of melatonin secretion decreased significantly in group III, suggesting that the nychthemeral pattern of melatonin secretion was changed in patients with LDRMCs. Comparison of the three groups suggests a slight but insignificant phase advance and amplitude decrease of circadian melatonin secretion related to both evolution and treatment of Parkinson's disease. Despite the lack of a global desynchronization in other circadian biologic rhythms, the circadian secretion pattern of melatonin is modified in patients with LDRMCs.

Aged↗