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F Grandas

Publications and source records attributed to F Grandas.

At least 37 records · Page 2Linked to original sources

Motor response to repeated dopaminergic stimulation in Parkinson's disease.

Recent studies giving subcutaneous apomorphine or intravenous levodopa boluses have not found clear evidence of behavioral hyposensitivity to repeated dopaminergic stimulation in Parkinson's disease (PD). Here we analyze that data, and review experimental findings in animal models and our previous experience with parkinsonian patients. We conclude that acute tolerance to pulsatile stimulation is likely to play a role in the pathophysiology of motor fluctuations in PD.

Animals↗

Time interval between repeated injections conditions the duration of motor improvement to apomorphine in Parkinson's disease.

Behavioral hyposensitivity to repeated apomorphine administration occurs in fluctuating parkinsonian patients. To determine to what extent the interval between doses influences the response, we administered equal paired apomorphine injections to 10 fluctuating parkinsonian patients. Subjects received two apomorphine injections at 2-hour and at 4-hour intervals on different days after a 10- to 12-hour overnight period without levodopa. Following apomorphine doses at 2-hour intervals, the duration of response was reduced by 40% (61 versus 42 minutes, p less than 0.001) but was of equal duration when the doses were given at 4-hour intervals. These findings indicate that the interval between doses is a critical determinant of motor response. We postulate a time-dependent period of partial hyposensitivity to pulsatile DA stimulation.

Adult↗

[Motor fluctuations in Parkinson disease: risk factors].

We studied the histories of 173 patients with Parkinson's disease (1985-1987) chronically treated with levodopa + dopa decarboxylase inhibitor. Ninety four patients had daily motor fluctuations and 79 showed stable motor response. The most significant differences between fluctuating and stable patients were given by age at disease onset and duration of levodopa therapy. Patient with disease onset before 60 had a greater risk (p less than 0.001) of developing fluctuations. Delaying the initiation of levodopa treatment was not associated with a smaller incidence of fluctuations.

Adult↗

[Treatment with botulinum toxin in blepharospasm].

Blepharospasm is a cranial dystonia characterized by forceful spasms of the orbicularis oculi muscle which may lead to functional blindness in approximately two-thirds of patients. Botulinum toxin injections is a simple procedure, very effective and with little morbidity. It is considered as the treatment of choice for patients with disabling blepharospasm.

Blepharospasm↗

Clinical and CT scan findings in a case of cyanide intoxication.

A 39-year-old man showed a combination of severe parkinsonism and progressive dystonia following attempted suicide with sodium cyanide. Computed tomography (CT) scan showed bilateral lucencies in the putamen and external globus pallidus. The topography of lesions on CT scan closely correlated with the pathological findings described in a previous report of cyanide-induced parkinsonism. This is the first reported case of cyanide intoxication with delayed-onset dystonia.

Adult↗

Motor response following repeated apomorphine administration is reduced in Parkinson's disease.

Ten patients with Parkinson's disease (PD) with motor fluctuations under levodopa treatment were given repeated equal subcutaneous injections of apomorphine [minimal effective dose (MED)] in 1 day. The MED was defined as the dose of apomorphine necessary to induce at least 60% reduction of motor disability for a minimum period of 10 min. MED was found for each patient in previous study days. In eight a subcutaneous infusion of apomorphine was performed on a different day. Four patients with simple fluctuations ("wearing off") showed a progressive reduction of the motor response to apomorphine injections, but three of the four had a stable response (continuous "on") to apomorphine infusion. Six patients with complicated fluctuations also exhibited a decreasing response to successive apomorphine injections and often completely failed to respond to some of the boluses. The response to a subcutaneous infusion of apomorphine was unstable in three of four cases. These findings indicate that a reduction of striatal dopaminergic receptor sensitivity is associated with repeated "pulsatile" apomorphine administration in parkinsonian patients with oscillations of motor performance. It is suggested that altered regulation of dopaminergic receptor sensitivity following pulsatile stimulation with levodopa may be a relevant phenomenon in the pathogenesis of motor fluctuations in PD.

Adult↗

Motor complications associated with chronic levodopa therapy in Parkinson's disease.

Fluctuations and dyskinesias are the 2 main motor complications associated with chronic levodopa therapy. Striatal denervation following degeneration of the substantia nigra dopaminergic projections is probably the major pathophysiologic mechanism underlying motor fluctuations. In addition, pathologic modification of striatal receptors, partially related to the nonphysiologic delivery of levodopa in a discontinuous pulsatile mode, may be responsible for the various types of dyskinesias and sudden "off" episodes. Drugs capable of providing a stable dopaminergic stimulation should be particularly useful for preventing the development of motor complications in patients not yet treated. At the other end of the clinical spectrum, patients with complex fluctuations are the least likely to improve with slow-release levodopa preparations.

Dementia↗

The significance of ophthalmological symptoms in idiopathic blepharospasm.

Two hundred and seventy-two patients with idiopathic blepharospasm were reviewed to establish the role of local eye disease in their illness. The majority of patients (57%) had symptoms at the onset of their illness such as dryness of the eyes, grittiness, irritation or photophobia suggesting eye lid or ocular surface disease. Detailed ophthalmological examination at the time of presentation had been carried out in 170 of the 272 cases; 64% of these patients had ocular symptoms, and 40% had demonstrable ocular surface or eye lid pathology. Such pathology was usually bilateral, chronic and resistant to local treatment. Blepharospasm developed in these patients after a long latent period, often of many years. Unilateral pathology was acute, normally responded well to local treatment, but was followed by the development of bilateral blepharospasm usually within six months. Amongst all 272 patients, those without ocular symptoms at presentation rarely developed them subsequently; if they did, there were no abnormal signs. The data suggest that ophthalmological disorders may trigger idiopathic blepharospasm in a substantial proportion of cases predisposed to develop this condition.

Adolescent↗

Blepharospasm: a review of 264 patients.

The natural history and response to different treatments have been evaluated in 264 patients with blepharospasm. The mean age of onset was 55.8 years and there was a female preponderance of 1.8 to 1. Dystonia elsewhere was found in 78% of patients, usually in the cranial-cervical region, and appeared to follow a somatotopic progression. A family history of blepharospasm or dystonia elsewhere was found in 9.5% of cases, which suggests a genetic predisposition. Ocular lesions preceded the onset of blepharospasm in 12.1% of cases. The response to drugs was inconsistent, although initial improvement was experienced by one fifth of patients treated with anticholinergics. Twenty-nine bilateral facial nerve avulsion operations were performed with benefit in 27 cases; but recurrences appeared in 22, on average one year after surgery. Botulinum toxin injections were performed in 151 patients. Significant improvement was achieved in 118 cases. Mean duration of benefit was 9.2 weeks. Transient ptosis and diplopia were the commonest side effects.

Adolescent↗

Antiparkinsonian activity of a single oral dose of PHNO.

PHNO, a new D-2 agonist, was investigated in five patients with Parkinson's disease. In an acute, open, oral, dose-ranging study comparing benefit from single doses, 4 mg of PHNO was found to be equivalent to one tablet of Sinemet 25/250 mg. Adverse reactions were those anticipated for a dopaminomimetic agent. Because of its novel structure and apparent transcutaneous penetration, further studies on PHNO are desirable.

Administration, Oral↗

Continuous dopaminergic stimulation in Parkinson's disease.

Complex motor fluctuations and dyskinesias ("on-off" phenomenon) in Parkinson's disease can be corrected by parenteral administration of levodopa, levodopa-methyl-ester, lisuride and apomorphine. Levodopa and levodopa-methyl-ester may only be administered intravenously because of their low solubility. Lisuride and apomorphine are readily absorbed after subcutaneous administration. Repeated or continuous intravenous infusions of levodopa have been given for a few days, using a wearable "jacket-like" pump, with good results. So far, lisuride is the only dopamine agonist used for chronic treatment by continuous infusion. The "on-off" effect is adequately controlled in most patients by subcutaneous lisuride administration (plus oral levodopa). However, adverse effects, particularly psychiatric complications, constitute a major limiting factor for routine applications of this form of treatment. Subcutaneous apomorphine infusion is unlikely to become a standard therapeutic procedure in Parkinson's disease, but it is a very valuable research method to gain further insight into the pathophysiology of motor fluctuations in Parkinson's disease.

Antiparkinson Agents↗

Controlled release levodopa in Parkinson's disease: influence of selection criteria and conversion recommendations in the clinical outcome of 450 patients. STAR Study Group.

We present the results of an open, prospective, multicentric study including 450 patients with mild to moderate Parkinson's disease (PD) converted from standard Sinemet to Sinemet CR (controlled release; Dupont Pharma, Pavia, Italy). Patients with complex fluctuations and diphasic dyskinesias were excluded and the conversion was made after some recommendations, depending on the clinical problems and the daily dosage and administration schedule of standard (STD) Sinemet. The condition of more than 60% of the patients improved after the change and 80% of them preferred the CR formulation by the end of the study. We found a moderate, but significant, improvement in most of the efficacy parameters used, such as the Unified Parkinson's Disease Rating Scale (UPDRS), the Schawb and England scale, and dyskinesias and sleep questionnaires. Forty-five patients (10%) discontinued the study due to adverse effects (mainly gastrointestinal disturbances, functional deterioration, and dyskinesias). We conclude that Sinemet CR is a useful and safe therapeutic option in patients with mild and moderate PD. Selection of the patients is the most important outcome factor.

Aged↗