Brain structural and functional signatures of impulsive-compulsive behaviours in Parkinson's disease.

This study assessed brain structural and functional alterations in patients with Parkinson's disease and impulsive-compulsive behaviours (PD-ICB) compared with controls and PD no-ICB cases. Eighty-five PD patients (35 PD-ICB) and 50 controls were recruited. All subjects underwent three-dimensional T1-weighted, diffusion tensor (DT), and resting state functional magnetic resonance imaging (RS fMRI). We assessed cortical thickness with surface-based morphometry, subcortical volumes using FIRST, DT MRI metrics using region of interest and tractography approaches, and RS fMRI using a model free approach. Compared with controls, both PD groups showed a pattern of brain structural alterations in the basal ganglia (more evident in PD no-ICB patients), sensorimotor and associative systems. Compared with PD no-ICB, PD-ICB cases showed left precentral and superior frontal cortical thinning, and motor and extramotor white matter tract damage. Compared with controls, all patients had an increased functional connectivity within the visual network. Additionally, PD no-ICB showed increased functional connectivity of bilateral precentral and postcentral gyri within the sensorimotor network compared with controls and PD-ICB. Severity and duration of PD-ICB modulated the functional connectivity between sensorimotor, visual and cognitive networks. Relative to PD no-ICB, PD-ICB patients were characterised by a more severe involvement of frontal, meso-limbic and motor circuits. These data suggest ICB in PD as the result of a disconnection between sensorimotor, associative and cognitive networks with increasing motor impairment, psychiatric symptoms, and ICB duration. These findings may have important implications in understanding the neural substrates underlying ICB in PD.

Transcranial sonography in dopa-responsive dystonia.

BACKGROUND AND PURPOSE: Mutations in the GCH1 gene, encoding GTP cyclohydrolase 1, the enzyme critically important for dopamine production in nigrostriatal neurons, are the most common cause of dopa-responsive dystonia (DRD), characterized predominantly by limb dystonia, although parkinsonian features may also be present. It has been suggested that DRD is a neurochemical rather than neurodegenerative disorder. METHODS: Transcranial brain sonography, which might be a risk marker for nigral injury, was obtained from 141 subjects divided into four groups: (i) 11 patients with genetically confirmed DRD; (ii) 55 consecutive patients with Parkinson's disease (PD); (iii) 30 patients diagnosed as isolated adult-onset focal dystonia; and (iv) 45 healthy controls (HCs). RESULTS: Substantia nigra hyperechogenicity was present in 63.6% of patients with DRD, which was significantly different in comparison to patients with dystonia (20%) and HCs (6.7%), but not in comparison to the PD group (87.3%). Also, values of the maximal areas of substantia nigra hyperechogenicity in patients with DRD were higher in comparison to HCs, but significantly lower than among the PD group. CONCLUSIONS: We suggested that the observed transcranial brain sonography features in patients with DRD might primarily be risk markers for particular clinical features (parkinsonism, dystonia) occurring in the specific genetic context (i.e. GCH1 mutations), or might reflect compensated neurodegenerative processes triggered by the long-lasting dopamine deficiency due to the profound delay in levodopa treatment in our patients with DRD.

Management of dystonia in Europe: a survey of the European network for the study of the dystonia syndromes.

BACKGROUND AND PURPOSE: Dystonia is difficult to recognize due to its large phenomenological complexity. Thus, the use of experts in dystonia is essential for better recognition and management of dystonia syndromes (DS). Our aim was to document managing strategies, facilities and expertise available in various European countries in order to identify which measures should be implemented to improve the management of DS. METHODS: A survey was conducted, funded by the Cooperation in Science and Technology, via the management committee of the European network for the study of DS, which is formed from representatives of the 24 countries involved. RESULTS: Lack of specific training in dystonia by general neurologists, general practitioners as well as other allied health professionals was universal in all countries surveyed. Genetic testing for rare dystonia mutations is not readily available in a significant number of countries and neurophysiological studies are difficult to perform due to a lack of experts in this field of movement disorders. Tetrabenazine is only readily available for treatment of dystonia in half of the surveyed countries. Deep brain stimulation is available in three-quarters of the countries, but other surgical procedures are only available in one-quarter of countries. CONCLUSIONS: Internationally, collaboration in training, advanced diagnosis, treatment and research of DS and, locally, in each country the creation of multidisciplinary teams for the management of dystonia patients could provide the basis for improving all aspects of dystonia management across Europe.

A genome-wide survey and functional brain imaging study identify CTNNBL1 as a memory-related gene.

Unbiased genome-wide screens combined with imaging data on brain function may identify novel molecular pathways related to human cognition. Here we performed a dense genome-wide screen to identify episodic memory-related gene variants. A genomic locus encoding the brain-expressed beta-catenin-like protein 1 (CTNNBL1) was significantly (P=7 × 10(-8)) associated with verbal memory performance in a cognitively healthy cohort from Switzerland (n=1073) and was replicated in a second cohort from Serbia (n=524; P=0.003). Gene expression studies showed CTNNBL1 genotype-dependent differences in beta-catenin-like protein 1 mRNA levels in the human cortex. Functional magnetic resonance imaging in 322 subjects detected CTNNBL1 genotype-dependent differences in memory-related brain activations. Converging evidence from independent experiments and different methodological approaches suggests a role for CTNNBL1 in human memory.

Cerebrospinal fluid biomarkers of neurodegeneration in patients with juvenile and classic myotonic dystrophy type 1.

BACKGROUND AND PURPOSE: The aim of the present study was to analyze cerebrospinal fluid (CSF) levels of total tau (T-tau), phosphorylated tau (P-tau) and the 42-amino-acid form of ß-amyloid (Aß42 ) in patients with myotonic dystrophy type 1 (DM1), and their possible correlations with cognitive and behavioral manifestations in these patients. METHODS: Lumbar puncture was performed in 74 patients with DM1 [27 with the childhood/juvenile form (jDM1) and 47 with the adult form (aDM1) of the disease] and 26 control subjects who were subjected to orthopedic surgery. Sandwich ELISA was used for measuring the levels of T-tau, P-tau and Aß42. RESULTS: The CSF level of Aß42 was at its lowest in patients with jDM1 and at its highest in controls (P < 0.05). A tendency of T-tau and P-tau to increase was greater in aDM1 patients than in jDM1 patients and controls (P > 0.05). In both jDM1 and aDM1 patients, significant correlations were found between Aß42 and T-tau (rho = 0.81 and rho = 0.67, respectively, P < 0.01), as well as between Aß42 and P-tau (rho = 0.87 and rho = 0.67, respectively, P < 0.01). The Aß42/P-tau ratio decreased with age in aDM1 patients (rho = -0.30, P < 0.05). Only the level of Aß42 in the CSF of jDM1 patients was correlated with the size of the CTG expansion (rho = -0.53, P < 0.05). Only a few correlations were observed between levels of biomarkers and neuropsychological testing. CONCLUSION: The CSF level of Aß42 was decreased in patients with jDM1, whilst the Aß42/P-tau ratio was decreased in aDM1 patients. Positive correlations between Aß42 , T-tau and P-tau were observed in both forms of disease. Further studies with larger cohorts of DM1 patients are necessary.

Transcranial brain sonography findings in two main variants of progressive supranuclear palsy.

BACKGROUND AND PURPOSE: Progressive supranuclear palsy (PSP) can occur with two main clinical presentations, classified as classical Richardson's syndrome (PSP-RS) and as PSP-parkinsonism (PSP-P), the most common atypical PSP variant. The differential diagnosis between them is challenging. Therefore, we studied different ultrasound markers by transcranial sonography in individuals with PSP-RS and PSP-P, to test their value in the diagnostic work up of these patients. METHODS: Transcranial sonography was performed in 21 patients with PSP-RS and 11 patients with PSP-P. Echogenic sizes of the substantia nigra (SN) and the lenticular nuclei (LN), as well as the width of the third ventricle, were measured. RESULTS: Among the patients with PSP-RS and PSP-P, three (14%) and eight (73%) patients had a hyperechogenic SN (P = 0.020), respectively. Uni- or bilateral hyperechogenicity of the LN was observed in 67% and 36% of patients with PSP-RS and PSP-P, respectively (P = 0.101). Third ventricle was significantly wider in patients with PSP-RS (11.2 ±â€…2.3 mm) when compared with patients with PSP-P (7.5 ±â€…1.4 mm; P = 0.001). CONCLUSION: Our data, possibly reflecting pathological differences, primarily contribute supporting the view that the neurodegenerative process differs in the two PSP variants.

Glucocerebrosidase mutations in a Serbian Parkinson's disease population.

BACKGROUND AND PURPOSE: To screen for glucocerebrosidase (GBA) mutations in a Serbian Parkinson's disease (PD) population. METHODS: Glucocerebrosidase exons 8-11 harbouring the most common mutations were sequenced in 360 patients with PD and 348 controls from Serbia. Haplotype analysis was performed for the N370S mutation and compared with German and Ashkenazi Jewish carriers. RESULTS: Glucocerebrosidase mutations were significantly more frequent in patients with PD (21/360; 5.8%) vs. controls (5/348; 1.4%; OR = 4.25; CI, 1.58-11.40; P = 0.0041). Two patients with PD carried homozygous or compound heterozygous mutations in GBA. The N370S mutation accounted for about half of the mutated alleles in patients (10/23) but was absent amongst controls. Three novel variants were detected including two non-synonymous variants (D380V, N392S) in the patient group and one synonymous change (V459V) in a control. Carriers of the D409H mutation were also sequenced for H255Q, and all were found to carry the [D409H; H255Q] double-mutant allele. Genotyping suggested a common haplotype for all N370S carriers. CONCLUSION: Glucocerebrosidase mutations represent a PD risk factor in the Serbian population.

Summary of the recommendations of the EFNS/MDS-ES review on therapeutic management of Parkinson's disease.

OBJECTIVE: To summarize the 2010 EFNS/MDS-ES evidence-based treatment recommendations for the management of Parkinson's disease (PD). This summary includes the treatment recommendations for early and late PD. METHODS: For the 2010 publication, a literature search was undertaken for articles published up to September 2009. For this summary, an additional literature search was undertaken up to December 2010. Classification of scientific evidence and the rating of recommendations were made according to the EFNS guidance. In cases where there was insufficient scientific evidence, a consensus statement ('good practice point') is made. RESULTS AND CONCLUSIONS: For each clinical indication, a list of therapeutic interventions is provided, including classification of evidence.

EFNS/MDS-ES/ENS [corrected] recommendations for the diagnosis of Parkinson's disease.

BACKGROUND: A Task Force was convened by the EFNS/MDS-ES Scientist Panel on Parkinson's disease (PD) and other movement disorders to systemically review relevant publications on the diagnosis of PD. METHODS: Following the EFNS instruction for the preparation of neurological diagnostic guidelines, recommendation levels have been generated for diagnostic criteria and investigations. RESULTS: For the clinical diagnosis, we recommend the use of the Queen Square Brain Bank criteria (Level B). Genetic testing for specific mutations is recommended on an individual basis (Level B), taking into account specific features (i.e. family history and age of onset). We recommend olfactory testing to differentiate PD from other parkinsonian disorders including recessive forms (Level A). Screening for pre-motor PD with olfactory testing requires additional tests due to limited specificity. Drug challenge tests are not recommended for the diagnosis in de novo parkinsonian patients. There is an insufficient evidence to support their role in the differential diagnosis between PD and other parkinsonian syndromes. We recommend an assessment of cognition and a screening for REM sleep behaviour disorder, psychotic manifestations and severe depression in the initial evaluation of suspected PD cases (Level A). Transcranial sonography is recommended for the differentiation of PD from atypical and secondary parkinsonian disorders (Level A), for the early diagnosis of PD and in the detection of subjects at risk for PD (Level A), although the technique is so far not universally used and requires some expertise. Because specificity of TCS for the development of PD is limited, TCS should be used in conjunction with other screening tests. Conventional magnetic resonance imaging and diffusion-weighted imaging at 1.5 T are recommended as neuroimaging tools that can support a diagnosis of multiple system atrophy (MSA) or progressive supranuclear palsy versus PD on the basis of regional atrophy and signal change as well as diffusivity patterns (Level A). DaTscan SPECT is registered in Europe and the United States for the differential diagnosis between degenerative parkinsonisms and essential tremor (Level A). More specifically, DaTscan is indicated in the presence of significant diagnostic uncertainty such as parkinsonism associated with neuroleptic exposure and atypical tremor manifestations such as isolated unilateral postural tremor. Studies of [(123) I]MIBG/SPECT cardiac uptake may be used to identify patients with PD versus controls and MSA patients (Level A). All other SPECT imaging studies do not fulfil registration standards and cannot be recommended for routine clinical use. At the moment, no conclusion can be drawn as to diagnostic efficacy of autonomic function tests, neurophysiological tests and positron emission tomography imaging in PD. CONCLUSIONS: The diagnosis of PD is still largely based on the correct identification of its clinical features. Selected investigations (genetic, olfactory, and neuroimaging studies) have an ancillary role in confirming the diagnosis, and some of them could be possibly used in the near future to identify subjects in a pre-symptomatic phase of the disease.

A genome-wide survey of human short-term memory.

Recent advances in the development of high-throughput genotyping platforms allow for the unbiased identification of genes and genomic sequences related to heritable traits. In this study, we analyzed human short-term memory, which refers to the ability to remember information over a brief period of time and which has been found disturbed in many neuropsychiatric conditions, including schizophrenia and depression. We performed a genome-wide survey at 909 622 polymorphic loci and report six genetic variations significantly associated with human short-term memory performance after genome-wide correction for multiple comparisons. A polymorphism within SCN1A (encoding the α subunit of the type I voltage-gated sodium channel) was replicated in three independent populations of 1699 individuals. Functional magnetic resonance imaging during an n-back working memory task detected SCN1A allele-dependent activation differences in brain regions typically involved in working memory processes. These results suggest an important role for SCN1A in human short-term memory.

Scaling analysis of bilateral hand tremor movements in essential tremor patients.

Recent evidence suggests that the dynamic-scaling behavior of the time-series of signals extracted from separate peaks of tremor spectra may reveal existence of multiple independent sources of tremor. Here, we have studied dynamic characteristics of the time-series of hand tremor movements in essential tremor (ET) patients using the detrended fluctuation analysis method. Hand accelerometry was recorded with (500 g) and without weight loading under postural conditions in 25 ET patients and 20 normal subjects. The time-series comprising peak-to-peak (PtP) intervals were extracted from regions around the first three main frequency components of power spectra (PwS) of the recorded tremors. The data were compared between the load and no-load condition on dominant (related to tremor severity) and non-dominant tremor side and with the normal (physiological) oscillations in healthy subjects. Our analysis shows that, in ET, the dynamic characteristics of the main frequency component of recorded tremors exhibit scaling behavior. Furthermore, they show that the two main components of ET tremor frequency spectra, otherwise indistinguishable without load, become significantly different after inertial loading and that they differ between the tremor sides (related to tremor severity). These results show that scaling, a time-domain analysis, helps revealing tremor features previously not revealed by frequency-domain analysis and suggest that distinct oscillatory central circuits may generate the tremor in ET patients.

Intravascular large B-cell lymphoma of central nervous system - a report of two cases and literature review.

Intravascular large B-cell lymphoma (IVL) is a rare form of diffuse large B cell lymphoma (DBCL) frequently presenting with skin and/or central nervous system (CNS) involvement. IVL involves CNS in 75 - 85% of patients and neurological symptoms include sensory and motor deficits or neuropathies, meningoradiculitis, paresthesia, hypostenia, aphasia, dysarthria, hemiparesis, seizures, transient visual loss, vertigo and impaired cognitive function. Neuroimaging discloses CNS involvement only in half of patients with neurological symptoms because there are no pathognomonic neuroradiological findings for IVL; ischemic foci are the most common presentation pattern and therefore vasculitis is the most common differential diagnosis. According to all mentioned data, diagnosis of CNS IVL requires a histopathological confirmation. Brain biopsy is absolutely indicated in patients with progressive neurological deterioration with unclear abnormalities in cerebral MR imaging. A general policy is that patients with IVL should be considered to have disseminated disease and should be treated with systemic chemotherapy. In younger patients with unfavorable features the high-dose chemotherapy with autologous stem cell transplantation should be used. Nevertheless, the course of IVL is rapidly progressive and ultimately fatal.

Bcl-2: prolonging life in a transgenic mouse model of familial amyotrophic lateral sclerosis.

Mutations in the gene encoding copper/zinc superoxide dismutase enzyme produce an animal model of familial amyotrophic lateral sclerosis (FALS), a fatal disorder characterized by paralysis. Overexpression of the proto-oncogene bcl-2 delayed onset of motor neuron disease and prolonged survival in transgenic mice expressing the FALS-linked mutation in which glycine is substituted by alanine at position 93. It did not, however, alter the duration of the disease. Overexpression of bcl-2 also attenuated the magnitude of spinal cord motor neuron degeneration in the FALS-transgenic mice.

Long-term outcome in Serbian patients with Wilson disease.

BACKGROUND AND PURPOSE: To investigate survival rates, prognostic factors, and causes of death in Wilson disease (WD). METHODS: In the years 1980-2007, a cohort of 142 patients with WD was prospectively registered (54 presented with neurologic symptoms, 49 with hepatic symptoms, 33 had mixed form, and data were missing for six patients). The duration of follow-up for patients alive was 11.1 +/- 8.8 years. RESULTS: After initiation of treatment (d-penicillamine and zinc salts), 79% of patients had a stable or improved course of disease. Despite early diagnosis and appropriate therapy, 15 patients still had a relentlessly progressive course. Thirty patients died. The cumulative probability of survival in a 15-year period for the whole group was 76.7 +/- 4.9%. Better prognosis of WD was associated with male sex, younger age at onset, neurologic form of the disease, and treatment continuity. Causes of death were predominantly related to hepatic failure (16 patients), but also suicide (four patients) and cancer (three patients). CONCLUSION: Despite the relatively early diagnosis and treatment of our patients with WD, mortality was still considerably high.

SPG10 is a rare cause of spastic paraplegia in European families.

BACKGROUND: SPG10 is an autosomal dominant form of hereditary spastic paraplegia (HSP), which is caused by mutations in the neural kinesin heavy chain KIF5A gene, the neuronal motor of fast anterograde axonal transport. Only four mutations have been identified to date. OBJECTIVE: To determine the frequency of SPG10 in European families with HSP and to specify the SPG10 phenotype. PATIENTS AND METHODS: 80 index patients from families with autosomal dominant HSP were investigated for SPG10 mutations by direct sequencing of the KIF5A motor domain. Additionally, the whole gene was sequenced in 20 of these families. RESULTS: Three novel KIF5A mutations were detected in German families, including one missense mutation (c.759G>T, p.K253N), one in frame deletion (c.768_770delCAA, p.N256del) and one splice site mutation (c.217G>A). Onset of gait disturbance varied from infancy to 30 years of age. All patients presented clinically with pure HSP, but a subclinical sensory-motor neuropathy was detected by neurophysiology studies. CONCLUSIONS: SPG10 accounts for approximately 3% of European autosomal dominant HSP families. All mutations affect the motor domain of kinesin and thus most likely impair axonal transport. Clinically, SPG10 is characterised by spastic paraplegia with mostly subclinical peripheral neuropathy.

Identification of mutations in the PARK2 gene in Serbian patients with Parkinson's disease.

Mutations in the PARK2 (PRKN) gene are the most common cause of autosomal-recessive (AR) juvenile parkinsonism and young-onset Parkinson's disease (YOPD). >100 different variants have been reported, including point mutations, small indels and single or multiple exon copy number variations. Mutation screening of PARK2 was performed in 225 Serbian PD patients (143 males and 82 females) with disease onset before 50 years and/or positive family history with apparent AR inheritance. All coding regions and their flanking intronic sequences were amplified and directly sequenced. Whole exon multiplications or deletions were detected using Multiple Ligation Probe Amplification (MLPA) method. We identified 12 PD patients with PARK2 mutations (5.3%). Five patients (2.2%) had biallelic mutations and seven (3.1%) were single mutation carriers. Patients with compound heterozygous mutations had earlier onset of the disease compared to non-carriers (p = 0.005) or heterozygotes (p = 0.001). Other clinical features in mutation carriers were not different compared to non-carriers. In our cohort, sequence and dosage variants were equally represented in patients, inducing their first symptoms mainly before the age of 30. For efficient genetic testing strategy, patients with early, especially juvenile onset of PD were strong candidates for both dosage and sequence variants screening of PARK2 gene.

Comparison of temporal and stride characteristics in myotonic dystrophies type 1 and 2 during dual-task walking.

OBJECTIVE: We analyzed temporal and stride characteristics in patients with myotonic dystrophy type 1 (DM1) and type 2 (DM2) while performing dual mental and motor tasks, and investigated correlations between gait parameters and cognitive impairments. METHOD: Dual-task walking was performed by 37 patients (20 DM1 and 17 DM2) and 48 healthy subjects divided into two groups, age- and gender-matched control group for DM1 (HC1) and age- and gender-matched control group for DM2 (HC2). The subjects performed a basic walking task, dual-motor task, dual-mental task, and combined motor and mental task. RESULTS: DM1 and DM2 patients differed significantly in temporal and stride characteristics compared to HC. Main differences in DM1 were slower gait and shorter stride length, while both DM1 and DM2 patients had a higher degree of variation of the swing time during dual-task gait, a parameter that reflects posture and balance. Impact of the cognitive dual task on gait pattern changes was also observed. Visuospatial ability correlated with gait changes in DM1, while executive functions had stronger influence in DM2 (p<0.01). Both patient groups had leg muscle weakness. CONCLUSION: Gait pattern was impaired in both patient groups concerning temporal and stride characteristics. Dual-task walking paradigm may discover mild initial gait changes and could provide early identification of fall risks and predict possible falls in DM patients.

Prolactin and cortisol responses to fenfluramine in Parkinson's disease.

Dysfunction of the central serotonergic system has been associated with depression in Parkinson's disease. To evaluate central serotonergic function in Parkinson's disease in relation to depression, we examined prolactin and cortisol responses to a single-dose challenge with fenfluramine (60 mg orally), a serotonin releasing/uptake-inhibiting agent, in the course of 5 hours in 11 patients with Parkinson's disease associated with major depression (SADS-RDC), 22 nondepressed parkinsonians, and 20 age- and gender-matched healthy controls. No difference in cortisol responses were observed between the groups; however, prolactin responses to fenfluramine were significantly impaired in patients with Parkinson's disease compared to controls, and the response was significantly more blunted in parkinsonian patients with major depression in comparison with the nondepressed ones. These findings indicate that there is a diminished serotonergic responsivity in depression associated with Parkinson's disease.

Early development of levodopa-induced dyskinesias and response fluctuations in young-onset Parkinson's disease.

We evaluated whether patients with young-onset Parkinson's disease (PD) (onset between 21 and 40 years) develop levodopa-induced dyskinesias and motor response fluctuations more frequently and earlier than patients with older-onset PD (onset after 40 years) by determining the period from levodopa introduction to development of dyskinesias or fluctuations in 25 young-onset (mean age at onset, 33.54 years) and in 25 matched older-onset PD patients (mean age at onset, 55.76 years). Young-onset PD patients had significantly higher frequency for both dyskinesias and fluctuations after both 3 and 5 years of levodopa. Young-onset PD patients also developed both levodopa-induced dyskinesias and fluctuations earlier than older-onset PD patients. We suggest that the introduction of levodopa therapy in patients with young onset PD should be postponed as long as possible.

Sudden hearing loss as the initial monosymptom of multiple sclerosis.

Hearing loss is an uncommon symptom in multiple sclerosis. We report two patients in whom unilateral sudden hearing loss was the first monosymptomatic manifestation of multiple sclerosis. We confirmed the initial central auditory dysfunction suggested by audiometric findings and brainstem auditory evoked potentials by MRI, which showed a unilateral pontine lesion in one patient and a lesion in the medulla oblongata in the other.