摘要:

SummaryThe description of multiple classes of opioid receptors has had a major impact on our understanding of the mechanisms of analgesia. Three major classes of opioid receptors have been defined: mu, kappa, and delta. The mu receptors have been further subclassified into two distinct subtypes (mu1 and mu2), as have the delta receptors (delta1 and delta2). Kappa receptors have been subdivided into kappa1, kappa2, or kappa3 subtypes. All of these subtypes modulate pain perception, with the exception of the kappa2 receptor, which has not been adequately examined. Supraspinal systems have been described for mu1, kappa3, and delta2 receptors while mu2, kappa1, and delta1 receptors modulate pain at the spinal level. In addition to their ability to act independently, the various systems also interact synergistically with each other. Thus, the relief of pain involves the complex interaction of at least six receptor systems. This review discusses the implications of opiate receptor multiplicity on the control of pain.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryVasculitis can be a systemic manifestation of hypersensitivity to many drugs, among them anticonvulsants. The clinical manifestations include rash and renal, hepatic, and pulmonary involvement. Diagnosis is based upon clinical findings and a characteristic biopsy showing granulocytic and sometimes eosinophilic infiltrates around small blood vessels, especially venules. A severe form of hypersensitivity vasculitis, with extensive visceral involvement and poor prognosis, has been encountered very rarely following phenytoin and in isolated cases following carbamazepine and trimethadione administration. Drug-induced systemic lupus erythematosus is much more frequent, with distinct clinical and laboratory abnormalities. The syndrome was described following treatment with most anticonvulsants in clinical use—phenytoin, carbamazepine, ethosuximide, trimethadione, primidone, and valproate, but not phenobarbital or benzodiazepines. The early recognition of these syndromes as being related to drugs is important, because they usually remit upon withdrawal of the offending agent.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryThe issue of whether there is a relationship between essential tremor (ET) and Parkinson's disease (PD) is controversial partly due to the confusion regarding the accurate diagnosis of these conditions. The presence of postural tremor, which often occurs in PD, by itself is insufficient for the diagnosis of ET. Most epidemiological studies have shown that there is no association between these two conditions. Some studies, but not others have found a higher prevalence of tremor in family members of PD patients. Clinical, positron emission tomography scan, and neuropathological data have failed to show any relationship between these two conditions. It is concluded that there is no relationship between ET and PD and that when these two conditions are seen in the same patient, this represents a chance occurrence of two common diseases.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryThe aim of this study was to examine the quantitative relationship between activity monitor measures and clinical scores of patients with Parkinson disease (PD). Motor activity was recorded continuously for 5 to 6 days at home with a wrist-worn activity monitor in 69 PD patients and 59 healthy controls. Clinical scores of the patients, age, and sex were submitted to multiple regression analysis to examine the quantitative relationship with measures reflecting the activity level and the proportion of activity and immobility over time. The patients' age, sex, and scores representing hypokinesia and rigidity and resting tremor explained approximately 50% of the variance of the motor activity measures. All motor activity measures declined with age; the rate of decline was similar for the patients and controls. Sex emerged as a predictor of the motor activity measures in the patients only. Male patients with PD showed significantly lower values for all motor activity measures than female patients and controls. Our results show that activity monitoring can be used as an objective quantitative assessment in PD.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryWe studied the effects of modafinil, a putative central α-1 agonist, on the excessive daytime sleepiness (EDS) of 10 narcoleptic patients while using a double-blind design and objective measurements of vigilance. There were two treatment periods, in which either modafinil or placebo was used; each lasted four weeks and was preceded by a 2-week “run-in” period and separated by a 2-week “wash-out” period. The effects of treatment on EDS were evaluated by daily home questionnaires and a psychomotor performance test, the Four Choice Reaction Time Test (FCRTT). Modafinil reduced the daily number of sleep attacks significantly, and markedly improved performances during the FCRTT. Results of this study suggest that modafinil is effective in treating EDS in narcolepsy, and that noradrenergic mechanisms could be involved in the physiopathology of EDS in that disorder.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryIt was recently shown that early treatment with deprenyl in patients with Parkinson's disease can delay the need for initiation of levodopa therapy. It was therefore suggested that deprenyl may slow down disease progression. Alternatively, the observed stabilization of clinical disability may merely reflect drug-induced symptomatic benefit. We therefore examined a possible short-term beneficial effect of deprenyl (10 mg/day) as the first and only drug in 15 consecutive de novo patients. Bradykinesia was quantitatively assessed by computerized analysis of isometric force/time curves of biceps and triceps bilaterally and by calculation of simple reaction time (RT) and maximal muscle contraction rate (MMCR). We also measured maximal muscle force, evaluated clinical status by the Unified Parkinson's Disease Rating Scale (UPDRS) motor score, and recorded patients' subjective reports. All tests were carried out before and at 1 and 2 months of treatment. Only one patient reported a beneficial effect. No significant changes in the UPDRS or score or muscle force were observed. In contrast, MMCR and RT improved at 1 month by an average of 12.1 and 7.2%, respectively (p < 0.01, paired t test). This improvement persisted after 2 months of treatment. Study shows that deprenyl monotherapy exerts a short-term beneficial effect in de novo parkinsonian patients. This effect, however, appears to be small, subclinical, and probably cannot account for the observed delay in the need to start levodopa therapy.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryResults of therapeutic trials with physostigmine in the treatment of Alzheimer disease (AD) have been inconsistent and controversy persists concerning safety and efficacy. In a double-blind, placebo-controlled, crossover study, patients received 6 weeks of oral physostigmine (OP) and placebo in random order. Twenty-nine patients with AD received as much as 16 mg/day of OP and were assessed with neuropsychological and functional measures. No significant cardiac side effects were noted, though other systemic adverse effects were noted, requiring dose reduction in four patients. There was a slight but significant improvement (12%) in performance on the selective reminding test with physostigmine and the memory performance was correlated with dosage. This improvement compares favorably with the 15% decrease in scores seen in an untreated comparison cohort followed for an equivalent time period. There was a trend toward an improvement in communication and a reduction in memory complaint. These results suggest that oral physostigmine is safe and may improve memory in AD.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryDifferent pathophysiological mechanisms may underly orthostatic hypotension (OH) observed in neurological degenerative disorders. The present study investigates the responses to the pharmacological activation of sympathetic pathways induced by yohimbine (0.2 mg/kg orally) through measurements of plasma catecholamine levels in parkinsonian patients with (n = 9) or without OH (n = 11), in patients with multiple system atrophy (MSA) plus OH (n = 9), and in controls (n = 6). Basal norepinephrine plasma levels in parkinsonian patients with OH (71 ± 11 pg/ml) were significantly lower (p < 0.05) than in parkinsonian patients without OH (280 ± 25 pg/ml) or in controls (259 ± 48 pg/ml). In patients with MSA plus OH, basal catecholamine plasma levels were in the normal range (344 ± 54 pg/ml). Yohimbine significantly increased norepinephrine (p < 0.05) but not epinephrine plasma levels in all groups. However, the increment obtained in parkinsonian patients with OH ( + 53 ± 18 pg/ml) remained significantly lower (p < 0.05) than in parkinsonian patients without OH or in controls ( + 638 ± 140 and + 457 ± 103 pg/ml, respectively) as well as in MSA plus OH (+ 633 ± 142 pg/ml). Yohimbine failed to modify the blood pressure and heart rate at the dose used. The results suggest that the yohimbine test is useful to elucidate the site of the dysfunction of the efferent sympathetic pathways in these two conditions. In Parkinson disease with OH, the lesion is both central and postganglionnic, whereas in MSA it is only centrally located.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryTo evaluate two different dosage regimens for albendazole (7.5 mg/ kg twice a day or 5.0 mg/kg three times a day), a study was performed in 10 patients with a diagnosis of parenchymal brain cysticercosis. Each patient received both regimens sequentially according to a randomized, crossover design. Blood and urine samples were taken once the drug steady state had been reached. Plasma levels of albendazole sulfoxide at steady state were determined using a HPLC method. In spite of a great intersubject variability observed with both regimens in the area under the curve (AUC) and in the minimum steady-state plasma concentration (Cp min ss), no statistically significant differences were found in these parameters. We suggest that a regimen of 7.5 mg/kg every 12 h can favorably replace the currently used regimen of 5 mg/kg every 8 h.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID

摘要:

SummaryTo examine selegiline's dosing effects, we studied 16 Parkinson disease patients with motor fluctuations in a double-blind, crossover trial of selegiline at 0, 5, and 10 mg daily. Patients' motor diaries, disability scores, and walking speed were marginally improved, with no advantage of 10 mg over 5 mg found. We conclude that in patients with motor fluctuations, selegiline provides modest symptomatic effects, with daily dosing of 5 mg being indistinguishable from 10 mg.

ISSN:0362-5664    

出版商:OVID    

年代:1993

数据来源: OVID