Clinically-relevant variants in the STUB1 gene have been associated with an autosomal dominant spinocerebellar ataxia 48 (SCA48), a recently described inherited neurodegenerative condition that is characterised by cognitive and psychiatric changes. To describe the clinical phenotype and genetic findings of three new Australian probands with STUB1 to expand the current understanding of the spectrum of clinical presentation and natural history of SCA48. Clinical and genetic review of patients diagnosed with SCA48 ataxia drawn from our centres.
View Article and Find Full Text PDFBackground: Mitochondrial diseases represent an important potential cause of cardiomyopathy and should be considered in patients presenting with multisystem manifestations. Timely diagnosis of a mitochondrial disorder is needed as it can have reproductive implications for the offspring of the proband.
Case Summary: We describe a case of undifferentiated rising and persistent troponin elevation in a 70-year-old female with only mild heart failure symptoms and signs.
Background: Advances in genomics provide improved opportunities for diagnosis of complex neurogenetic disorders, yet the optimal approach to translate these benefits to the outpatient clinic is unclear.
Aims: We retrospectively reviewed referral indications and outcomes of an integrated multidisciplinary team (MDT) clinic pathway for adults with suspected neurogenetic disorders. The associated cost implications were estimated.
Adult-onset cerebellar ataxias are a group of neurodegenerative conditions that challenge both genetic discovery and molecular diagnosis. In this study, we identified an intronic (GAA) repeat expansion in fibroblast growth factor 14 (FGF14). Genetic analysis of 95 Australian individuals with adult-onset ataxia identified four (4.
View Article and Find Full Text PDFBackground: Heterozygous KMT2B variants are a common cause of dystonia. A novel synonymous KMT2B variant, c.5073C>T (p.
View Article and Find Full Text PDFTraditional vascular imaging focuses on non-invasive cross-sectional imaging to assess luminal morphology; however, the vessel wall itself may be specifically involved in many diseases. Newer pulse sequences, and particularly black blood MRI of intracranial vessels, have brought a paradigm shift in understanding the pathophysiology of many vasculopathies. Black blood MRI of intracranial vessel walls can help in a range of pathologies with differing pathophysiology, including intracranial atherosclerosis, aneurysms, vasculitis and vasculopathy, moyamoya disease, dissection and vertebrobasilar hypoplasia.
View Article and Find Full Text PDFObjective: To improve understanding of disease pathophysiology in anti-myelin-associated glycoprotein (anti-MAG) neuropathy to guide further treatment approaches.
Methods: Anti-MAG neuropathy patients underwent clinical assessments, nerve conduction and excitability studies, and ultrasound assessment.
Results: Patients demonstrated a distinctive axonal excitability profile characterised by a reduction in superexcitability [MAG: -14.
Pervasive avoidance behaviour is a core feature of anxiety disorders. However, little is known about how the availability of avoidance modulates learned threat responding. To assess this question, we recorded avoidance behaviour, electrodermal activity and expectancy ratings in 53 healthy participants during an associative learning paradigm with embedded unavoidable and avoidable trials.
View Article and Find Full Text PDFBackground Migraine is highly prevalent in women (18%). Peak morbidity affects their most productive years, coinciding with peak fertility. Hormonal contraception is often tailored for migraine prevention.
View Article and Find Full Text PDFWith the rapid evolution of understanding of neurological channelopathies comes a need for sensitive tools to evaluate patients in clinical practice. Neurological channelopathies with a single-gene basis can manifest as seizures, headache, ataxia, vertigo, confusion, weakness and neuropathic pain and it is likely that other genetic factors contribute to the phenotype of many of these disorders. Ion channel dysfunction can result in abnormal cell membrane excitability but utilisation of advanced neurophysiology techniques has lagged behind developments in clinical, genetic and imaging evaluation of channelopathies.
View Article and Find Full Text PDFIndian Pacing Electrophysiol J
March 2016
Ion channel dysfunction causes a range of neurological disorders by altering transmembrane ion fluxes, neuronal or muscle excitability, and neurotransmitter release. Genetic neuronal channelopathies affecting peripheral axons provide a unique opportunity to examine the impact of dysfunction of a single channel subtype in detail in vivo. Episodic ataxia type 2 is caused by mutations in CACNA1A, which encodes the pore-forming subunit of the neuronal voltage-gated calcium channel Cav2.
View Article and Find Full Text PDFBackground And Objective: Heterozygous mutations in KCNA1 cause episodic ataxia type 1 (EA1), an ion channel disorder characterised by brief paroxysms of cerebellar dysfunction and persistent neuromyotonia. This paper describes four previously unreported families with EA1, with the aim of understanding the phenotypic spectrum associated with different mutations.
Methods: 15 affected individuals from four families underwent clinical, genetic and neurophysiological evaluation.
Benign familial neonatal epilepsy is a neuronal channelopathy most commonly caused by mutations in KCNQ2, which encodes the K(v)7.2 subunit of the slow K(+) channel. K(v)7.
View Article and Find Full Text PDFBackground: The myopathy associated with mutations in the nuclear-encoded mitochondrial DNA maintenance gene POLG, coding for the catalytic subunit of DNA polymerase, is typically proximal with early ophthalmoplegia.
Results: We report two unrelated patients in whom a distal, mainly upper limb, myopathy was the predominant and early clinical feature. One patient also suffered with marked cachexia.
Episodic ataxia type 1 is a neuronal channelopathy caused by mutations in the KCNA1 gene encoding the fast K(+) channel subunit K(v)1.1. Episodic ataxia type 1 presents with brief episodes of cerebellar dysfunction and persistent neuromyotonia and is associated with an increased incidence of epilepsy.
View Article and Find Full Text PDFObjectives: To compare the effectiveness of a short-term leg-strengthening exercise program with that of attentional control on improving strength, walking abilities, and function 1 year after hip fracture.
Design: Randomized controlled pilot study.
Setting: Patients' homes.
The "Trond" protocol of nerve excitability tests has been used widely to assess axonal function in peripheral nerve. In this study, the routine Trond protocol was expanded to refine assessment of cAMP-dependent, hyperpolarization-activated current (I(h)) activity. I(h) activity is generated by hyperpolarization-activated, cyclic nucleotide-modulated (HCN) channels in response to hyperpolarization.
View Article and Find Full Text PDFClinical neurophysiology has become an invaluable tool in the diagnosis of muscle channelopathies, but the situation is less clear cut with neuronal channelopathies. The genetic episodic ataxias are a group of disorders with heterogeneous phenotype and genotype, but share in common the feature of intermittent cerebellar dysfunction. Episodic ataxia (EA) types 1 and 2 are the most widely recognised of the autosomal dominant episodic ataxias and are caused by dysfunction of neuronal voltage-gated ion channels.
View Article and Find Full Text PDFThe CB2 receptor is an attractive therapeutic target for analgesic and anti-inflammatory agents. Herein we describe the discovery of a novel class of oxadiazole derivatives from which potent and selective CB2 agonist leads were developed. Initial hit 7 was identified from a cannabinoid target-biased library generated by virtual screening of sample collections using a pharmacophore model in combination with a series of physicochemical filters.
View Article and Find Full Text PDFStructural modifications to the central portion of the N-arylamide oxadiazole scaffold led to the identification of N-arylpiperidine oxadiazoles as conformationally constrained analogs that offered improved stability and comparable potency and selectivity. The simple, modular scaffold allowed for the use of expeditious and divergent synthetic routes, which provided two-directional SAR in parallel. Several potent and selective agonists from this novel ligand class are described.
View Article and Find Full Text PDFThe lymphocyte-specific kinase (Lck), a member of the Src family of cytoplasmic tyrosine kinases, is expressed in T cells and natural killer (NK) cells. Genetic evidence, including knockout mice and human mutations, demonstrates that Lck kinase activity is critical for normal T cell development, activation, and signaling. Selective inhibition of Lck is expected to offer a new therapy for the treatment of T-cell-mediated autoimmune and inflammatory disease.
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