Heart-rate variability as a new marker for freezing predisposition in Parkinson's disease.

Introduction: Freezing of gait (FoG) is a debilitating symptom of advanced Parkinson's disease (PD) characterized by a sudden, episodic stepping arrest despite the intention to continue walking. The etiology of FoG is still unknown, but accumulating evidence unraveled physiological signatures of the autonomic nervous system (ANS) around FoG episodes. Here we aim to investigate for the first time whether detecting a predisposition for upcoming FoG events from ANS activity measured at rest is possible.

Upward perturbations trigger a stumbling effect.

Background: Vertical perturbations are one major cause of falling. Incidentally, while conducting a comprehensive study comparing effects of vertical versus horizontal perturbations, we commonly observed a stumbling-like response induced by upward perturbations. The present study describes and characterizes this stumbling effect.

Dopaminergic medication reduces interhemispheric hyper-synchronization in Parkinson's disease.

Introduction: We previously reported on interhemispheric cortical hyper synchronization in PD. The aim of the present study was to address the hypothesis that increased interhemispheric cortical synchronization in PD is related to dopamine deficiency and is correlated with motor function.

Methods: We studied participants with PD and characterized cortical synchronization with reference to brain regions.

Patterns of whole-body muscle activations following vertical perturbations during standing and walking.

Background: Falls commonly occur due to losses of balance associated with vertical body movements (e.g. reacting to uneven ground, street curbs).

Exploring the perceptions and stigmatizing experiences of Israeli family caregivers of people with Parkinson's disease.

Providing care to people with Parkinson's disease (PD) poses challenges for family carers, including experiencing stigmatic beliefs -i.e., family stigma.

Seeing Gravity: Gait Adaptations to Visual and Physical Inclines - A Virtual Reality Study.

Using advanced virtual reality technology, we demonstrate that exposure to virtual inclinations visually simulating inclined walking induces gait modulations in a manner consistent with expected gravitational forces (i.e., acting upon a free body), suggesting vision-based perception of gravity.

Advanced virtual reality-based rehabilitation of balance and gait in clinical practice.

Background: Extensive research shows that virtual reality (VR) enhances motor learning and has advantages in balance and gait rehabilitation of neurological patients. There is still uncertainty, however, as for the practicality and efficacy of VR in long-term clinical routine. The objective of this study was to report on 3 years of clinical practice conducting VR-based rehabilitation of balance and gait in a large medical center.

Excessive phase synchronization in cortical activation during locomotion in persons with Parkinson's disease.

Introduction: Parkinson's disease (PD) is characterized by gait disturbances, which become severe during the advanced stages of the disease. Though gait impairments in Parkinson's disease have been extensively described in terms of spatiotemporal gait parameters, little is known regarding associated patterns of cortical activity. The objective of the present study is to test if interhemispheric synchronization differs between participants with PD and healthy elderly controls (NPD).

Coupling Between Leg Muscle Activation and EEG During Normal Walking, Intentional Stops, and Freezing of Gait in Parkinson's Disease.

In this paper, we apply novel techniques for characterizing leg muscle activation patterns via electromyograms (EMGs) and for relating them to changes in electroencephalogram (EEG) activity during gait experiments. Specifically, we investigate changes of leg-muscle EMG amplitudes and EMG frequencies during walking, intentional stops, and unintended freezing-of-gait (FOG) episodes. FOG is a frequent paroxysmal gait disturbance occurring in many patients suffering from Parkinson's disease (PD).

Intersegmental coordination patterns are differently affected in Parkinson's disease and cerebellar ataxia.

The law of intersegmental coordination (Borghese et al. 1996) may be altered in pathological conditions. Here we investigated the contribution of the basal ganglia (BG) and the cerebellum to lower limb intersegmental coordination by inspecting the plane's orientation and other parameters pertinent to this law in patients with idiopathic Parkinson's disease (PD) or cerebellar ataxia (CA).

Kufor-Rakeb Syndrome/PARK9: One Novel and One Possible Recurring Ashkenazi ATP13A2 Mutation.

Kufor-Rakeb syndrome (KRS)/PARK9 presents with autosomal recessive young onset Parkinson's disease (YOPD), spastic paraparesis, abnormal eye movements and facial myokymia. KRS is caused by homozygous/compound heterozygous inactivating mutations in ATP13A2. Two affected siblings (born to non-consanguineous Jewish parents) presenting a similar KRS phenotype (onset age 27, 23), carried compound heterozygous pathogenic variants in ATP13A2: c.

Advantages of virtual reality in the rehabilitation of balance and gait: Systematic review.

Background: Virtual reality (VR) has emerged as a therapeutic tool facilitating motor learning for balance and gait rehabilitation. The evidence, however, has not yet resulted in standardized guidelines. The aim of this study was to systematically review the application of VR-based rehabilitation of balance and gait in 6 neurologic cohorts, describing methodologic quality, intervention programs, and reported efficacy.

Transethnic genome-wide scan identifies novel Alzheimer's disease loci.

Introduction: Genetic loci for Alzheimer's disease (AD) have been identified in whites of European ancestry, but the genetic architecture of AD among other populations is less understood.

Methods: We conducted a transethnic genome-wide association study (GWAS) for late-onset AD in Stage 1 sample including whites of European Ancestry, African-Americans, Japanese, and Israeli-Arabs assembled by the Alzheimer's Disease Genetics Consortium. Suggestive results from Stage 1 from novel loci were followed up using summarized results in the International Genomics Alzheimer's Project GWAS dataset.

Cutaneous malignant melanoma and Parkinson disease: Common pathways?

The mechanisms underlying the high prevalence of cutaneous malignant melanoma (CMM) in Parkinson disease (PD) are unclear, but plausibly involve common pathways. 129Ser-phosphorylated α-synuclein, a pathological PD hallmark, is abundantly expressed in CMM, but not in normal skin. In inherited PD, PARK genes harbor germline mutations; the same genes are somatically mutated in CMM, or their encoded proteins are involved in melanomagenesis.

Parkinson disease (PARK) genes are somatically mutated in cutaneous melanoma.

Objective: To assess whether Parkinson disease (PD) genes are somatically mutated in cutaneous melanoma (CM) tissue, because CM occurs in patients with PD at higher rates than in the general population and PD is more common than expected in CM cohorts.

Methods: We cross-referenced somatic mutations in metastatic CM detected by whole-exome sequencing with the 15 known PD (PARK) genes. We computed the empirical distribution of the sum of mutations in each gene (Smut) and of the number of tissue samples in which a given gene was mutated at least once (SSampl) for each of the analyzable genes, determined the 90th and 95th percentiles of the empirical distributions of these sums, and verified the location of PARK genes in these distributions.

Micrographia, much beyond the writer's hand.

Introduction: This review on micrographia aims to draw the clinician's attention to non-Parkinsonian etiologies, provide clues to differential diagnosis, and summarize current knowledge on the phenomenology, etiology, and mechanisms underlying micrographia.

Methods: A systematic review of the existing literature was performed.

Results: Micrographia, namely small sized handwriting has long been attributed to Parkinson's disease.

Self-selected gait speed--over ground versus self-paced treadmill walking, a solution for a paradox.

Background: The study of gait at self-selected speed is important. Traditional gait laboratories being relatively limited in space provide insufficient path length, while treadmill (TM) walking compromises natural gait by imposing speed variables. Self-paced (SP) walking can be realized on TM using feedback-controlled belt speed.

Alzheimer's disease and the elderly in Israel: are we paying enough attention to the topic in the Arab population?

With the continuing rise in the elderly population, Alzheimer’s disease (AD) and dementia represent an increasing public health concern worldwide. In recent years, research has focused on the relationship between AD and ethnicity. Israel, a multiethnic society, provides a natural laboratory for research on ethnicity and health.

Estimating the risk for conversion from mild cognitive impairment to Alzheimer's disease in an elderly Arab community.

Background: Vascular risk factors and lack of formal education may increase the risk of Alzheimer's disease (AD).

Objective: To determine the contribution of vascular risk factors and education to the risk of mild cognitive impairment (MCI) and AD and to estimate the risk for conversion from MCI to AD.

Methods: This door-to-door survey was performed by an Arab-speaking team in Wadi Ara villages in Israel.

Exploring determinants of progression in Parkinson's disease. Is there a difference among Jewish ethnic groups?

Introduction: Parkinson's disease (PD) displays an individually variable rate of progression, of which the underlying mechanisms are largely unknown, but may involve genetic factors. In this study, we aimed to explore the effect of ethnic origin on PD progression rate in Israeli Jews, as expressed by time from onset until reaching Hoehn and Yahr stage 3 (HY3).

Methods: Consecutive patients with PD followed bi-annually at the Movement Disorders Institute at Sheba Medical Center, were included.

Higher frequency of certain cancers in LRRK2 G2019S mutation carriers with Parkinson disease: a pooled analysis.

Importance: Patients with Parkinson disease (PD) who harbor LRRK2 G2019S mutations may have increased risks of nonskin cancers. However, the results have been inconsistent across studies.

Objectives: To analyze pooled data from 5 centers to further examine the association between LRRK2 G2019S mutation and cancer among patients with PD and to explore factors that could explain discrepancies.