Characterising Upper Limb Movements in Huntington's Disease and the Impact of Restricted Visual Cues

Influence of aging, disease, exercise, and injury on human hand movements: A systematic review

The human hand is a versatile organ that performs a variety of activities in daily life. The coordination of digits allows them to deal with objects of various sizes and shapes with an appropriate range of motions (ROM). A systematic literature review was performed to identify the clinical and non-clinical factors which affected the normal ROM, grip strength (GS), and dexterity of hand. The overall outcomes of the systematic review showed that: the performance of the individual declined as the age progressed; the performance of the dominant hand (DH) of an individual was better compared to his/her non-dominant hand (NDH); the tasks performed by a healthy hand was more efficient compared to a diseased one; appropriate rehabilitation programs/exercise techniques after a disease or injury improved the ROM, GS, and dexterity of hand post-surgery on par to a healthy hand.

Dual Task Effects on Speed and Accuracy During Cognitive and Upper Limb Motor Tasks in Adults With Stroke Hemiparesis

Background

Adults with stroke need to perform cognitive-motor dual tasks during their day-to-day activities. However, they face several challenges owing to their impaired motor and cognitive functions.

Objective

This case-controlled pilot study investigates the speed and accuracy tradeoffs in adults with stroke while performing cognitive-upper limb motor dual tasks.

Methods

Ten adults with stroke and seven similar-aged controls participated in this study. The participants used a robotic arm for the single motor task and participated in either the serial sevens (S7) or the controlled oral word association test (COWAT) for single-cognitive task. For the dual task, the participants performed the motor and cognitive components simultaneously. Their speed and accuracy were measured for the motor and cognitive tasks, respectively.

Results

Two-sample t-statistics indicated that the participants with stroke exhibited a lower motor accuracy in the cross task than in the circle task. The cognitive speed and motor accuracy registered by the subjects with stroke in the dual task significantly decreased. There was a negative linear correlation between motor speed and accuracy in the subjects with stroke when the COWAT task was performed in conjunction with the cross task (ρ = -0.6922, p = 0.0388).

Conclusions

This study proves the existence of cognitive-upper limb motor interference in adults with stroke while performing dual tasks, based on the observation that their performance during one or both dual tasks deteriorated compared to that during the single task. Both speed and accuracy were complementary parameters that may indicate clinical effectiveness in motor and cognitive outcomes in individuals with stroke.

CRISPR Genome Editing Technology and its Application in Genetic Diseases: A Review

Gene therapy has been a long lasting goal for scientists, and there are many optimal methods and tools to correct disease-causing mutations in humans. Recently, the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology has been progressively adopted for the assessment a treatment of human diseases, including thalassemia, Parkinson's disease, cystic fibrosis, glaucoma, Huntington's disease, and Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS). CRISPR sequences belong to the bacterial immune system, which includes the nuclease Cas enzyme and an RNA sequence. The RNA sequence is unique and pathogen-specific, and identifies and binds to the DNA of invasive viruses, allowing the nuclease Cas enzyme to cut the identified DNA and destroy the invasive viruses. This feature provides the possibility to edit mutations in the DNA sequence of live cells by replacing a specific targeted RNA sequence with the RNA sequence in the CRISPR system. Previous studies have reported the improvement steps in confrontation with human diseases caused by single-nucleotide mutations using this system. In this review, we first introduce CRISPR and its functions and then elaborate on the use of CRISPR in the treatment of human diseases.

Rethinking Functional Outcome Measures: The Development of a Novel Upper Limb Token Transfer Test to Assess Basal Ganglia Dysfunction

The basal ganglia are implicated in a wide range of motor, cognitive and behavioral activities required for normal function. This region is predominantly affected in Huntington's disease (HD), meaning that functional ability progressively worsens. However, functional outcome measures for HD, particularly those for the upper limb, are limited meaning there is an imperative for well-defined, quantitative measures. Here we describe the development and evaluation of the Moneybox test (MBT). This novel, functional upper limb assessment was developed in accordance with translational neuroscience and physiological principles for people with a broad disease manifestation, such as HD. Participants with HD (n = 64) and healthy controls (n = 21) performed the MBT, which required subjects to transfer tokens into a container in order of size (Baseline Transfer), value (Complex Transfer) with and without reciting the alphabet (Dual Transfer). Disease specific measures of motor, cognition, behavior, and function were collected. HD patients were grouped into disease stage, from which, discriminative and convergent validity was assessed using Analysis of Variance and Pearson's correlation respectively. Manifest HD participants were slower than pre-manifest and control participants, and achieved significantly lower MBT total scores. Performance in the Complex Transfer and Dual Transfer tasks were significantly different between pre-manifest and stage 1 HD. All MBT performance variables significantly correlated with routinely used measures of motor, cognition, behavior, and function. The MBT provides a valid, sensitive, and affordable functional outcome measure. Unlike current assessments, MBT performance significantly distinguished the subtle differences between the earliest disease stages of HD, which are the populations typically targeted in clinical trials.