Effect of bilateral deep-brain stimulation on oral control of patients with parkinsonism.

We assessed the oral system of parkinsonian patients treated with bilateral chronic stimulation of the ventral intermediate nucleus of the thalamus (Vim), and of the subthalamic nucleus (STN) to compare the effects of these procedures on the articulatory organs. Force transducers were used to sample ramp-and-hold force contractions generated by the upper lip, lower lip and tongue at 1- and 2-newton target force levels, as well as maximal force. Fourteen healthy control subjects and 14 parkinsonian patients participated in this study. After an overnight fast the patients were evaluated under two conditions: during bilateral stimulation and 1 h after stopping stimulation. With Vim stimulation, dynamic and static control of the articulatory organs was worsened while with STN stimulation it was greatly improved. The target of stimulation differently influences the oral system and modulates neuronal structures involved in speech.

Effect of bilateral subthalamic nucleus stimulation and dopatherapy on oral control in Parkinson's disease.

This study focuses on the speech organs of a parkinsonian patient who initially had been treated with levodopa for 13 years, and had become severely disabled by motor fluctuations. This patient has been treated with bilateral chronic stimulation of the subthalamic nucleus (STN) for the last 2 years. Upper lip, lower lip and tongue force production were examined before surgery under off and on medication conditions, and 2 years after surgery under off and on stimulation conditions. We compared the effect of stimulation and dopatherapy on the speech organs. L-Dopa had a poor effect whereas bilateral stimulation improved oral control and speech intelligibility. These results suggest that STN stimulation influences speech organs in a different way from the dopaminergic system and similarly affects oral and limb motor systems.

Changes in some pro- and antioxidants in rat cerebellum after chronic alcohol intake.

Some pro- and antioxidants were measured in the cerebellum from ethanol-fed rats using ethanol administration in drinking water as a model of moderate alcohol intoxication. After 4 weeks of ethanol intake, a 30% increase in the nonheme iron content in the cerebellum occurred in ethanol-fed rats as compared to control animals. The low-molecular-weight-chelated iron (LMWC-Fe) content as well as the percentage of total nonheme iron represented by LMWC-Fe were increased in the cerebellar cytosol after chronic ethanol administration. Cerebellar copper and selenium concentrations were lower and zinc concentration higher in ethanol-fed rats than in controls. Ethanol consumption decreased the cerebellar vitamin E level. Glutathione S-transferase [EC 2. 5. 1. 18] activity was higher, whereas glutathione peroxidase [glutathione: H2O2 oxidoreductase, EC 1. 11. 1. 9] activity was not altered by ethanol treatment. No significant changes in cerebellar lipid peroxidation, carbonyl protein content, or glutamine synthetase [L-glutamate:ammonia ligase (ADP-forming) EC 6. 3. 1. 2] activity were observed. These results suggest that adaptative increases in some elements of the antioxidant defense may counteract the increase in LMWC-Fe, a pro-oxidant factor, and prevent the occurrence of overt cellular lipid and protein damage. However, after 8 weeks of ethanol intake, the activity of glutamine synthetase, an enzyme specially sensitive to inactivation by oxygen radicals, was decreased, suggesting that this prevention was not totally achieved.

EMG biofeedback in the treatment of dysarthria.

An EMG biofeedback technique was developed for the treatment of dysarthria. It aims at increasing the quantity of information about the myofacial system which can be used by the patients to improve the control of their musculature and speech production. This therapy tool consisting of an application software module (copyright INSERM/CNRS 92) is adaptable for a lot of muscles and speech realizations.

Acute and long-term effects of subthalamic nucleus stimulation in Parkinson's disease.

In animal models of Parkinson's disease (PD), it is postulated that the excessive output from the subthalamic nucleus (STN) plays a critical role. Selective lesions or high frequency electrical stimulation of the STN can alleviate parkinsonian symptoms in MPTP-treated monkeys. We decided to carry out STN stimulation in patients suffering from severe akinetic forms of PD. After approval of the institutional ethical committee, we operated on a parkinsonian patient aged 51, suffering for 8 years from a strongly disabling akinetorigid form of PD, complicated by an on-off effect (Hoehn and Yahr stage 5 in the worst-off motor phase). Stereotactic surgery was done on one side under local anesthesia. The theoretical target was chosen according to stereotactic atlases, based on ventriculographic landmarks such as anterior and posterior commissures (AC and PC). The final position of the chronic electrodes was optimized using electrophysiological recording and stimulation along with clinical assessment and surface EMG of agonist and antagonist muscles of the examined limbs. A spontaneous increase in neuronal activity was recorded in an area located 2-4 mm under the level of the intercommissural plane, 10 mm from the midline, at mid-distance between AC and PC. Within the same place, a 130-Hz stimulation induced acute and reversible akinesia alleviation mainly on the contralateral limbs, comparable to that obtained with dopaminergic drugs. No dyskinesia, such as hemiballism, was induced by introduction of electrodes or by stimulation. Then a long-term quadripolar DBS Medtronic electrode was inserted in this area. Studies of the effects of chronic stimulation were extensively performed to determine the best spatiotemporal and electrical stimulation variables.(ABSTRACT TRUNCATED AT 250 WORDS)

Speech rehabilitation in dysarthria.

Although the usefulness of speech rehabilitation in disorders such as asphasia is now recognized, many clinicians estimate that speech treatments for dysarthrics are of limited value. The conceptual approach to dysarthrias is a physiological approach that emphasizes the component-by-component analysis of the peripheral speech mechanism. The selection and sequencing of treatment procedures follow directly from the physiological nature and severity of involvement in each component.

[Effects of the stimulation of the subthalamic nucleus in Parkinson disease]. / Effets de la stimulation du noyau sous-thalamique dans la maladie de Parkinson.

In Parkinson's disease, experimental studies favour a neuronal hyperactivity of the subthalamic nucleus. We carried out a subthalamic nucleus electrical stimulation in a patient aged 51, suffering for 8 years from a severe akineto-rigid form of Parkinson's disease, complicated with an on-off effect. Stereotaxic surgery was done under local anaesthesia on one side. Within the theoretical target, a 130 Hz stimulation induced akinesia alleviation mainly on the contralateral limbs. No abnormal movement was noticed. Then a long-term quadripolar DBS Medtronic electrode was inserted in that area. The study of the effects of chronic stimulation is in progress to determine the best temporal and electrical stimulation variables.

Amlodipine compared to nitrendipine in hypertensive patients: the effects on toleration in relationship to the onset of action.

Amlodipine and nitrendipine are calcium antagonists of the 1,4-dihydropyridine group which differ in their pharmacokinetic and pharmacodynamic properties. The clinical relevance of these differences was investigated in a study designed to compare the efficacy and safety of once-daily amlodipine (5 mg) and nitrendipine (20 mg) in patients with mild-to-moderate essential hypertension. Ambulatory blood pressure monitoring and conventional measurements showed that amlodipine and nitrendipine produced comparable reductions in blood pressure after 4 weeks of treatment. However, the onset of the antihypertensive effect was gradual for amlodipine, while most of the reduction achieved at the end of treatment with nitrendipine was seen after the first dose. There were no significant changes in heart rate with amlodipine, but significant increases occurred during the first 6 h of nitrendipine treatment. Amlodipine was associated with a significantly lower incidence of vasodilator-related adverse effects at initiation of therapy (headache, flushing, tachycardia) compared with nitrendipine, which may reflect its slower onset of action. The different pharmacodynamic and toleration profiles of amlodipine and nitrendipine at therapeutically equivalent doses suggest that amlodipine may have advantages in the treatment of hypertension, especially in terms of the low incidence of acute side effects, which may ultimately translate into improved patient compliance.