Among patients with lumbar spinal stenosis, with or without degenerative spondylolisthesis, decompression surgery plus fusion surgery did not result in better clinical outcomes at 2 years and 5 years than did decompression surgery alone. (Funded by an Uppsala institutional Avtal om Läkarutbildning och Forskning [Agreement concerning Cooperation on Medical Education and Research] and others; Swedish Spinal Stenosis Study ClinicalTrials.gov number, NCT01994512.).
In patients with Parkinson's disease, the therapeutic efficacy of L-DOPA medication is gradually lost over time, and abnormal involuntary movements, dyskinesias, gradually emerge as a prominent side-effect in response to previously beneficial doses of the drug. Here we show that dyskinesia induced by chronic L-DOPA treatment in rats with 6-hydroxydopamine-induced lesions of the nigrostriatal dopamine pathway is critically dependent on the integrity and function of the serotonergic system. Removal of the serotonin afferents, or dampening of serotonin neuron activity by 5-HT1A and 5-HT1B agonist drugs, resulted in a near-complete block of the L-DOPA-induced dyskinesias, suggesting that dysregulated dopamine release from serotonin terminals is the prime trigger of dyskinesia in the rat Parkinson's disease model. In animals with complete dopamine lesions, the spared serotonin innervation was unable to sustain the therapeutic effect of L-DOPA, suggesting that dopamine released as a 'false transmitter' from serotonin terminals is detrimental rather than beneficial. The potent synergistic effect of low doses of 5-HT1A and 5-HT1B agonists to suppress dyskinesia, without affecting the anti-parkinsonian effect of L-DOPA in presence of spared dopamine terminals, suggests an early use of these drugs to counteract the development of dyskinesia in Parkinson's disease patients.
The risk for HCC, liver decompensation, and death in patients with liver cirrhosis related to HCV was markedly reduced after SVR, but a long-term risk of developing HCC remains for up to 8 years. Cirrhotic patients with HCV who achieve SVR should therefore maintain long-term surveillance for HCC. Future studies aimed to better identify those with remaining long-term risk for HCC are needed.
Appearance of dyskinesia is a common problem of long-term l-DOPA treatment in Parkinson's disease patients and represents a major limitation for the pharmacological management of the motor symptoms in advanced disease stages. We have recently demonstrated that dopamine released from serotonin neurons is responsible for l-DOPA-induced dyskinesia in 6-hydroxydopamine (6-OHDA)-lesioned rats, raising the possibility that blockade of serotonin neuron activity by combination of 5-HT(1A) and 5-HT(1B) agonists could reduce l-DOPA-induced dyskinesia. In the present study, we have investigated the efficacy of 5-HT(1A) and 5-HT(1B) agonists to counteract l-DOPA-induced dyskinesia in 1-methyl-4-phenyl 1,2,3,6-tetrahydropyridine (MPTP)-treated macaques, the gold standard model of Parkinson's disease. In addition, we have studied the ability of this treatment to prevent development of l-DOPA-induced dyskinesia in 6-OHDA-lesioned rats. The results demonstrate the existence of a potent synergistic effect between 5-HT(1A) and 5-HT(1B) agonists in their ability to dampen l-DOPA-induced dyskinesia in the MPTP-treated macaques. Sub-threshold doses of the drugs, which individually produced no effect, were able to reduce the abnormal involuntary movements by up to 80% when administered in combination, without affecting the anti-parkinsonian properties of l-DOPA. Furthermore, chronic administration of low doses of the 5-HT(1) agonists in combination was able to prevent development of dyskinesia, and reduce the up-regulation of FosB after daily treatment with l-DOPA in the rat 6-OHDA model. Our results support the importance of a clinical investigation of the effect of 5-HT(1A) and 5-HT(1B) agonists, particularly in combination, in dyskinetic l-DOPA-treated Parkinson's disease patients.
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