Both infection with the human immunodeficiency virus type 1 (HIV) and zidovudine (formerly called azidothymidine [AZT]) cause myopathy. To identify criteria for distinguishing zidovudine-induced myopathy from that caused by primary HIV infection, we reviewed the histochemical, immunocytochemical, and electron-microscopical features of muscle-biopsy specimens from 20 HIV-positive patients with myopathy (15 of whom had been treated with zidovudine) and compared the findings with the patients' clinical course and response to various therapies. Among the zidovudine-treated patients, the myopathy responded to prednisone in four, to the discontinuation of zidovudine in eight, and to nonsteroidal anti-inflammatory drugs in two. Numerous "ragged-red" fibers, indicative of abnormal mitochondria with paracrystalline inclusions, were found in the biopsy specimens from the zidovudine-treated patients but not in those from the other patients. The number of these fibers appeared to correlate with the severity of the myopathy. All the patients, regardless of whether they had been treated with zidovudine, had inflammatory myopathy characterized by degenerating fibers, cytoplasmic bodies, and endomysial infiltrates consisting of CD8+ cells (mean +/- SD, 60.7 +/- 6.4 percent) and macrophages (39.2 +/- 6.4 percent) associated with Class I major histocompatibility complex (MHC-I) antigens (HLA-A, -B, and -C antigens) in the muscle fibers. The numbers and percentages of CD8+ cells and macrophages were similar in both the zidovudine-treated and the untreated HIV-positive patients. Specimens obtained on repeat muscle biopsy from two patients in whom the myopathy responded to the discontinuation of zidovudine showed remarkable histologic improvement. We conclude that long-term therapy with zidovudine can cause a toxic mitochondrial myopathy, which coexists with a T-cell-mediated inflammatory myopathy that is restricted to MHC-I antigen, and is indistinguishable from the myopathy associated with primary HIV infection or polymyositis in HIV-seronegative patients.
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Circ Cardiovasc Imaging
January 2025
Division of Cardiology, Department of Medicine, University of California, San Francisco (L.C., S.D., D.B., J.J.T., Q.F., L.T., A.H.R., R.J., S.H., H.H.H., Z.H.T., N.B.S., F.N.D.).
Background: A subset of patients with mitral valve prolapse (MVP), a highly heritable condition, experience sudden cardiac arrest (SCA) or sudden cardiac death (SCD). However, the inheritance of phenotypic imaging features of arrhythmic MVP remains unknown.
Methods: We recruited 23 MVP probands, including 9 with SCA/SCD and 14 with frequent/complex ventricular ectopy.
Biallelic pathogenic variants in the nebulin ( ) gene lead to the congenital muscle disease nemaline myopathy. In-frame deletion of exon 55 (ΔExon55) is the most common disease-causing variant in . Previously, a mouse model of was developed; however, it presented an uncharacteristically severe phenotype with a near complete reduction in transcript expression that is not observed in exon 55 patients.
View Article and Find Full Text PDFHum Genome Var
January 2025
Division of Molecular Genetics, Center for Medical Science, Fujita Health University Hospital, Toyoake, Aichi, Japan.
UBA1 is an E1 ubiquitin-activating enzyme that initiates the ubiquitylation of target proteins and is thus a key component of the ubiquitin signaling pathway. Three disorders are associated with pathogenic variants of the UBA1 gene: vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome, lung cancer in never smokers (LCINS), and X-linked spinal muscular atrophy (XL-SMA, SMAX2). We here report a case of infantile respiratory distress syndrome followed by continuing neuromuscular symptoms.
View Article and Find Full Text PDFInt J Oral Sci
January 2025
Department of Stomatology, Tangdu Hospital & State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, School of Stomatology, The Fourth Military Medical University, Xi'an, China.
Temporomandibular joint osteoarthritis (TMJ-OA) is a common disease often accompanied by pain, seriously affecting physical and mental health of patients. Abnormal innervation at the osteochondral junction has been considered as a predominant origin of arthralgia, while the specific mechanism mediating pain remains unclear. To investigate the underlying mechanism of TMJ-OA pain, an abnormal joint loading model was used to induce TMJ-OA pain.
View Article and Find Full Text PDFBMJ Open
January 2025
Siriraj Health Policy Unit, Mahidol University Faculty of Medicine Siriraj Hospital, Bangkok, Thailand
Objectives: To evaluate the cost-utility of botulinum toxin A (BoNT-A) for treating upper limb (UL) and lower limb (LL) post-stroke spasticity.
Design: Using a Markov model, adopting a societal perspective and a lifetime horizon with a 3% annual discount rate, the cost-utility analysis was conducted to compare BoNT-A combined with standard of care (SoC) with SoC alone. Costs, utilities, transitional probabilities and treatment efficacy were derived from 5-year retrospective data from tertiary hospitals and meta-analysis.
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