Vacuolar myopathy in a dog resembling human sporadic inclusion body myositis

Sporadic inclusion body myositis (sIBM) is the most common myopathy in people over the age of 50 years. While immune-mediated inflammatory myopathies are well documented in dogs, sIBM has not been described. An 11-year-old dog with chronic and progressive neuromuscular dysfunction was evaluated for evidence of sIBM using current pathologic, immunohistochemical and electron microscopic diagnostic criteria. Vacuoles and congophilic intracellular inclusions were identified in cryostat sections of multiple muscle biopsies and immunostained with antibodies against amyloid-β peptide, amyloid-β precursor protein, and proteosome 20S of the ubiquitin–proteosome system. Cellular infiltration and increased expression of MHC Class I antigen were observed. Cytoplasmic filamentous inclusions, membranous structures, and myeloid bodies were identified ultrastructurally. These observations constitute the first evidence that both the inflammatory and degenerative features of human sIBM can occur in a non-human species

Painful and painless mutations of SCN9A and SCN11A voltage-gated sodium channels

Chronic pain is a global problem affecting up to 20% of the world’s population and has a significant economic, social and personal cost to society. Sensory neurons of the dorsal root ganglia (DRG) detect noxious stimuli and transmit this sensory information to regions of the central nervous system (CNS) where activity is perceived as pain. DRG neurons express multiple voltage-gated sodium channels that underlie their excitability. Research over the last 20 years has provided valuable insights into the critical roles that two channels, NaV1.7 and NaV1.9, play in pain signalling in man. Gain of function mutations in NaV1.7 cause painful conditions while loss of function mutations cause complete insensitivity to pain. Only gain of function mutations have been reported for NaV1.9. However, while most NaV1.9 mutations lead to painful conditions, a few are reported to cause insensitivity to pain. The critical roles these channels play in pain along with their low expression in the CNS and heart muscle suggest they are valid targets for novel analgesic drugs

Electrical stimulation of the posterior tibial nerve reduces neuropathic pain in patients with polyneuropathy

Ron Dabby,1,2 Menachem Sadeh,1,2 Ilan Goldberg,1,2 Vitaly Finkelshtein1,2 1Department of Neurology, Wolfson Medical Center, Holon, 2Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel Abstract: Peripheral neuropathic pain (PNP) is caused by neuronal damage to the peripheral nervous system and usually affects the distal extremities. This open-label study examined the effect of short-term peripheral nerve stimulation (PNS) on individuals with PNP due to polyneuropathy. A total of 12 patients (mean age, 63.0 ± 10.0 years, 41.7% male) with daily bilateral PNP for at least 6 months (mean duration, 7.4 ± 7.8 years) received a total of six direct electrical stimulation therapies to the posterior tibial nerve at 3–4-day intervals. Eight patients completed the study and were included in the efficacy analysis. The average pain at baseline was 36.6 ± 3.80 estimated by the Short-Form McGill Pain Questionnaire. After the last stimulation, pain was significantly reduced by 85.5% to 4.88 ± 3.1 (p = 0.008). Six patients (75%) had over 50% decrease in pain after the first stimulation therapy and 99.2% after the final stimulation therapy. The patients also reported statistically significant decreases in pain level (measured by visual analog scale), ranging from 54.85% to 87.50% after each of the stimulations as compared to the pain experienced prior to the stimulations. The procedure was safe without any serious adverse events. PNS has demonstrated excellent efficacy and improvement of PNP symptoms. Further studies in larger patient populations are warranted. Keywords: peripheral nerve stimulation, posterior tibial nerve stimulation, peripheral neuropathic pain, quality of lif

An autosomal recessive cerebellar ataxia syndrome with upward gaze palsy, neuropathy, and seizures

he authors describe three siblings born to consanguineous parents with early onset ataxia, dysarthria, myoclonic, generalized tonic clonic seizures, upward gaze palsy, extensor plantar reflexes, sensory neuropathy, and normal cognition. Direct screening excluded mutations in FRDA, TDP1, and SACS genes and at 8344, 3243, and 8993 positions of mitochondrial DNA. Linkage analysis excluded AOA-1, EPM1, EPM2A, EPM2B, CAMOS, and recessive ataxias linked to chromosome 9q34-9qter. This clinical constellation may represent a distinct form of early onset cerebellar ataxia