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The basal ganglia have been proposed as one of the neural correlates of timekeeping functions. Both encoding and memory retrieval components for time perception are impaired in Parkinson's disease (PD). The aim of our study was to investigate in hemi-Parkinsonian patients the existence of a specific alteration in memory for time depending on the affected side, to better understand the contribution of the left or right basal ganglia circuits in different components of time perception. Right and left hemi-PD patients performed a time reproduction task in which they were required to reproduce in the same session short (5 s) and long (15 s) time intervals, in off- and on-therapy condition. While the right hemi-PD patients overestimated the shorter interval, only the left hemi-PD group showed the memory migration effect, overestimating the shorter and underestimating the longer time intervals. These results argue for a critical involvement of the right basal ganglia in memory retrieval for time intervals, in the range of seconds.

Twenty-six metals and the oxidative status in 71 patients affected by Parkinson's disease and 44 healthy individuals were compared in order to identify potential biomarkers of the disease. In the patients, the following significant imbalances were found (p < or = 0.05): i) in serum, an increment of Ca, Mg, Ni, Si and V, and a decrement of Cd, Co, Fe, Li, Sn, Zn and Zr; ii) in blood, raised levels of Co, Li, Ni and Si and decreased of Al, Be, Ca, Cd, Fe, Mg, Mo, Sn, Zn and Zr; iii) increased formation of oxidant species and lowered anti-oxidant capacity (p < or = 0.001 for both). Barium, Bi, Cr, Cu, Hg, Mn, Pb, Sb, Sr, Tl and W did not change with the disease. The best discriminating variables between patients and controls were Cd, Co, Fe, Ni and Si in serum (91.2% of cases correctly classified), and Al, Cd, Co, Fe, Mo and Si in blood (98.2% of cases properly classified).

Background: Entacapone is a COMT inhibitor used in Parkinson's disease (PD) patients, as an adjunctive therapy to L-dopa in order to prolong its bioavailability and thus its clinical effect. However, previous studies reported entacapone-induced L-dopa to have lower C(max) and delayed t(max) values, coupled with a delayed onset of the clinical effect, possibly suggesting an interference between the two drugs. The aim of our study was to evaluate whether a delayed entacapone administration in association with standard L-dopa/carbidopa, may in some subjects improve the entacapone effects on L-dopa AUC and thus on the clinical 'on time' duration., Methods: Twenty-eight idiopathic advanced PD patients were blindly evaluated in three different test days, following administration of carbidopa/L-dopa or carbidopa/L-dopa plus co-administered entacapone or plus entacapone administered with 30 min of delay., Results: The AUC, the 'on time' and UPDRS score of the whole group were improved by both modalities of entacapone administration. An ex post analysis showed that the delayed entacapone administration produced a significant improvement in a subgroup of 10 non-responding patients to the co-administration., Conclusion: We suggest that the delayed administration should be attempted in the subjects not improved by entacapone co-administration.

Quantifications of Al, Ca, Cu, Fe, Mg, Mn, Si and Zn were performed in urine, serum, blood and cerebrospinal fluid (CSF) of 26 patients affected by Parkinson's disease (PD) and 13 age-matched controls to ascertain the potential role of biological fluids as markers for this pathology. Analyses were performed by Inductively Coupled Plasma Atomic Emission Spectrometry and Sector Field Inductively Coupled Plasma Mass Spectrometry. The serum oxidant status (SOS) and anti-oxidant capacity (SAC) were also determined. Results showed a decreasing trend for Al in all the fluids of PD patients, with the strongest evidence in serum. Calcium levels in urine, serum and blood of PD patients were significantly higher than in controls. Copper and Mg concentrations were significantly lower in serum of PD patients. Levels of Fe in urine, blood and CSF of patients and controls were dissimilar, with an increase in the first two matrices and a decrease in CSF. No significant difference was found in levels of Mn between patients and controls. Urinary excretion of Si was significantly higher in PD subjects than in controls. No clear difference between Zn levels in the two groups was found for serum, urine or CSF, but an increase in Zn levels in the blood of PD patients was observed. The SOS level in PD was significantly higher while the corresponding SAC was found to be lower in patients than in controls, in line with the hypothesis that oxidative damage is a key factor in the pathogenesis of PD. The results on the whole indicate the involvement of Fe and Zn (increased concentration in blood) as well as of Cu (decreased serum level) in PD. The augmented levels of Ca and Mg in the fluids and of Si in urine of patients may suggest an involuntary intake of these elements during therapy.

Object: The authors compared the effects of deep brain stimulation (DBS) in the globus pallidus internus (GPi) with those in the subthalamic nucleus (STN) in patients with Parkinson disease (PD) in whom electrodes had been bilaterally implanted in both targets., Methods: Eight of 14 patients with advanced PD in whom electrodes had been implanted bilaterally in both the GPi and STN for DBS were selected on the basis of optimal DBS effects and were studied 2 months postsurgery in off- and on-stimulus conditions and after at least 1 month of pharmacological withdrawal. Subcutaneous administration of an apomorphine test dose (0.04 mg/kg) was also performed in both conditions. Compared with the off status, the results showed less reduction in the Unified PD Rating Scale Section III scores during DBS in the GPi (43.1%) than during DBS of the STN (54.5%) or DBS of both the STN and GPi (57.1%). The difference between the effects of DBS in the GPi compared with that in the STN or simultaneous DBS was statistically significant (p < 0.01). In contrast, no statistical difference was found between DBS in the STN and simultaneous DBS in the STN and GPi (p < 0.9). The improvement induced by adding apomorphine administration to DBS was similar in all three stimulus modalities. The abnormal involuntary movements (AIMs) induced by apomorphine were almost abolished by DBS of the GPi, but were not affected by stimulation of the STN. The simultaneous stimulation of STN and GPi produced both antiparkinsonian and anti-AIM effects., Conclusions: The improvement of parkinsonian symptoms during stimulation of the GPi, STN, and both nuclei simultaneously may indicate a similar DBS mechanism for both nuclei in inducing antiparkinsonian effects, although STN is more effective. The antidyskinetic effects produced only by DBS of the GPi, with or without STN, may indicate different mechanisms for the antidyskinetic and antiparkinsonian activity related to DBS of the GPi or an additional mechanism in the GPi. These findings indicate that implantation of double electrodes for DBS should not be proposed as a routine procedure, but could be considered as a possible subsequent choice if electrode implantation for DBS of the STN does not control AIMs.

Entacapone is a specific, peripherally acting catechol- O-methyltransferase (COMT) inhibitor that prevents peripheral degradation of L-dopa, thus improving its bioavailability. Entacapone is known to have pharmacokinetics similar to standard L-dopa but not to that of controlled-release (CR) L-dopa. The aim was to determine whether delayed entacapone administration may prolong CR L-dopa half-life in comparison to the co-administration modality. We compared plasma L-dopa concentrations after co-administration of CR L-dopa and entacapone or after administration of CR and a delayed (30 and 90 minutes) entacapone dose in 10 parkinsonian patients. The area under the concentration-time curve and other pharmacokinetic parameters were not changed by the delayed administration of entacapone. Different temporal modalities of entacapone administration had similar effects on CR L-dopa pharmacokinetics and on L-dopa-induced clinical improvement.

Alterations in temporal estimation have been observed in Parkinson's disease (PD) and have been associated with dopaminergic dysfunction. To investigate whether deep brain stimulation might reverse these abnormalities in PD, patients treated with electrode implantation for subthalamic deep brain stimulation were required to reproduce time intervals in different experimental conditions (off deep brain stimulation/off therapy, on deep brain stimulation/off therapy, on therapy/off deep brain stimulation). Patients treated with deep brain stimulation in off deep brain stimulation/off therapy displayed the anomalous pattern of responses typically observed in PD. When subthalamic deep brain stimulation was turned on these abnormalities were significantly attenuated. Our findings reveal that subthalamic deep brain stimulation improves time perception in PD patients, supporting the critical role of basal ganglia in this cognitive function, probably mediated by facilitated thalamo-cortical projections to the prefrontal cortex.

The levels of the neuroactive steroids allopregnanolone (THP) and 5alpha-dihydroprogesterone (DHP) were quantified in the plasma of 11 (group 1) and in the liquor of 12 (group 2) Parkinson's disease (PD) patients using a gas-chromatographic/mass-spectrometric method. When compared with controls, both groups showed a significant decrease in DHP and THP concentrations. These decreases could be a useful marker of PD. Moreover, in view of the importance of GABA-ergic transmission to substantia nigra (SN) neurons and GABA-ergic modulation exerted by the two neuroactive steroids, our data indicate a global dysregulation of the SN GABA-ergic system in PD patients. Moreover, a lack of neuroprotective factors (i. e., GDNF, BDNF), promoted by DHP, may contribute to dopaminergic cell death.

Twenty right-handed patients affected by early/mild Parkinson's disease were evaluated in a randomised study using neuropsychological and clinical assessements during three treatment modalities: when in the off treatment condition, when on pramipexole, and when on l-dopa. In comparison to the off treatment condition, the DA-agonist pramipexole produced a significant impairment of short term verbal memory, attentional-executive functions and verbal fluency, while l-dopa did not. Moreover, pramipexole opposite to l-dopa, failed to improve FAS and Stroop tests. Present findings indicate that pramipexole may worsen cognitive functions although not exceeding normative values.

Relative regional blood flow of basal ganglia was studied by means of perfusion-weighted dynamic susceptibility (DSC) MRI. Parkinson's disease (PD) patients showed a significant inter-hemispheric asymmetry due to a higher perfusion in the more affected side, while normal subjects did not. PD exhibited an abnormal "asymmetry index" in the measured nuclei. A second DSC-MRI examination performed after subcutaneous apomorphine administration did not show any significant asymmetry in PD patients. DSC-MRI of basal ganglia confirms the asymmetry observed in PET studies of PD patients, suggesting that this method is a promising and low-cost technique in neurodegenerative diseases.

Aretrospective hospital-based case-control study was performed with the aim to evaluate the association between exposure to anesthesia and Alzheimer's disease (AD). A total of 115 AD patients, 230 Parkinson's disease (PD) patients and 230 patients with non-degenerative neurological disease were studied. Each AD case was matched for sex, age (+/-3 years) and geographic area of residence with four controls (2 PD patients and 2 with other neurological disease). Information about exposure to general anesthesia and other variables was gathered through hospital records. No associations were found between the risk of AD and the exposure to anesthesia in the 1 and 5 years preceding disease onset, nor between the risk of AD and the number of surgical operations. A significant difference was observed between the mean age of AD patients and controls undergoing surgical procedures. The present study reveals a lack of association between exposure to general anesthesia and AD. Prospective epidemiological studies are needed in order to investigate levels of exposure to anesthesia, as well as any possible relationships between anesthetic exposure and genetic factors (e. g. APOEepsilon4 genotype).

27 patients with essential tremor (ET) were studied to determine the cognitive feature of this condition. 15 familial cases and 12 cases with a family history Parkinson's disease (PD) were identified. Performances on frontal lobe tasks of ET patients were compared with those of 15 patients with PD and 15 healthy control subjects. The ET patients showed significant impairments both in attentional and conceptual thinking tasks, similar to those observed in the PD group. Despite the nosographic independence of the two conditions, data showed that the frontal lobe feature of ET was similar to those of PD, thus possibly suggesting a common dysregulation of dopamine pathways.

Objective: The aim was to describe the short-term (6 months) effects of olanzapine on behavioral and motor clinical manifestations in a group of 11 patients with Huntington disease., Method: An open-pilot study of olanzapine (5 mg) in patients with clinical and genetic diagnosis of Huntington disease was used. The Unified Huntington Disease Rating Scale for clinical assessment and the Total Functional Capacity score for the disease-stage evaluation were used. A statistical analysis was performed to compare the effects of olanzapine on the Unified Huntington Disease Rating Scale scores at time 0 (baseline) and at time 1 (6 months). Comparisons of motor scores, of single behavioral items, and of TFC scores were performed within the group., Results: The behavioral assessment score of items regarding depression, anxiety, irritability, and obsessions showed a significant improvement (range of p, 0.0134-0.048). Given the total behavioral scores (sum of all the items investigated), five patients significantly improved their behavioral score after a 6-month treatment (range of p, 0.013-0.047). Choreic movements improved, although not significantly (0.05 < or = p < or = 1)., Conclusions: Olanzapine is a potentially useful antipsychotic drug, with significant short-term effects on behavioral changes, mainly in patients with severe psychiatric symptoms at the onset. It might be considered as a possible therapeutic choice for treatment of Huntington disease.

Aim of our study was to investigate the different effects on attentional capacity of deep brain stimulation DBS (STN or GPi) and of l-dopa in PD patients. Patients were evaluated on-DBS/off-l-dopa, on-l-dopa/off-DBS, on-l-dopa/on-DBS and off-l-dopa/off-DBS. Our results indicate that DBS effects on attentional functions parallel those of l-dopa. A site independent (both STN and GPi) worsening of verbal fluency was observed, possibly connected to the stimulus effect on the cortico-subcortical-cortical loop.

This paper reviews the main neuropsychological features of movement disorders such as Parkinson's disease (PD), progressive supranuclear palsy (PSP), multiple system atrophy (MSA), Huntington's disease (HD), corticobasal degeneration (CBD), and diffuse Lewy body disease (DLBD). These neurodegenerative disorders all share a prominent frontal lobe-like syndrome which can be explained by damage to connections between the basal ganglia and the cortical areas involved in movement, and in behavioural and mood control. In this paper different types of cognitive and mood alteration are described in an attempt to identify additional reasons for the differential diagnosis of parkinsonism-like syndromes.

Recently, some case-control studies and case reports have shown an association between solvent exposure and parkinsonisms. We present a 55-year-old male parkinsonian patient with chronic exposure to n-hexane for 17 years. The results of neurophysiological (electromyography, evoked potentials), neuroradiological (MRI) and neuropsychological tests performed on the patient suggest a role of this solvent at the level of the central nervous system. Biological susceptibility to neurotoxic compounds is discussed briefly.

Primary orthostatic tremor is a regular fast lower limb tremor causing unsteadiness on standing. Treatment is generally unsatisfactory. A patient with primary orthostatic tremor who 9 years later developed levodopa responsive idiopathic Parkinson's disease is described. The patient exhibited the classic features of primary orthostatic tremor with relief of the tremor by walking or sitting while treated with levodopa. However, in the "off" state, when the benefits of levodopa disappeared, this orthostatic tremor was continuous and severely compromised the patient's gait. On the basis of this finding eight patients with primary orthostatic tremor were treated with levodopa. Five patients experienced benefit and elected to remain on long term treatment. This study is the first trial of therapy in primary orthostatic tremor and suggests that levodopa can lead to good symptomatic relief in this potentially disabling condition.

We present an unusual case of simultaneous bilateral cerebellar infarction in the territory of the medial and intermediate branches of the posterior inferior cerebellar arteries (mPICA). The patient, a 57-yr-old woman, had no risk factors for cerebrovascular disease but a long-standing hypertension. Pathogenetic hypotheses of this unusual ischemic site of lesion may be referred to: A) two PICAs arising from an occluded basilar artery; B) both medial branches arising from the same PICA on one side; C) a haemodynamic mechanism with hypoperfusion in the most peripheral branches of the arteries; D) a double, simultaneous embolic stroke in mPICAs territory. Based on clinical course, supraortic duplex-scan, echocardiography, MRI, angioMRI and CT scans, and digital subtraction angiography, none of these hypotheses could be clearly associated with the pathogenesis of the lesion. Nevertheless, we propose that an anomalous common mPICA for both cerebellar territories should represent the necessary condition for the ischemic insult and, simultaneously, other factors should intervene as possible determining events.

Basilar migraine is characterized by headache preceded by prodromal symptoms and signs of posterior cerebral circulation dysfunction. Few studies have focused on EEG findings in this condition or on the prognosis of occipital spike-wave complexes observed in either migraine or epilepsy. We now report a long-term follow-up (8-16 years) in seven children affected by basilar migraine who had EEG findings of occipital spike-wave complexes. Basilar migraine resolved and the EEG became normal in all subjects during the observation period, as did migraine with aura and seizures which developed in some of the patients after basilar migraine attacks ceased.

The antinociception of opiates is mediated through the activation of opioid receptors in several mid brain and brain stem areas. This paper reports that the forebrain area termed area tempestas (AT), first identified as a convulsant trigger area, is also a component of the endogenous pain suppression system. Unilateral AT application of DAMGO, morphine and U-50,488H in rats at doses in the nanogram range produced marked and dose-dependent increases in the latency to respond to nociceptive stimuli. A lower effect is found after application of DPDPE and DADLE. Antinociception is more evident in the hot plate than in the tail flick test. In the former test, the effect was restricted to the paws contralateral to the hemisphere of injection. Unilateral AT application of naltrexone (4 ng) reduced in the contralateral paws the antinociceptive effect that the bilateral AT application of morphine (20 ng/hemisphere) had induced in both body sides. Unilateral application of naltrexone, (20 ng) ICI 154, 129 (20 ng) and Win 44,441-3 (8 ng) antagonized the antinociceptive effect elicited by the systemic injection of morphine (2.5 mg/kg s), DPDPE (20 mg/kg s) and U-50,488H (20 mg/kg s), respectively. In the hot plate test, the antagonism was found in the paws ipsilateral and contralateral to the hemisphere of injection of the antagonists.