CD163+ macrophage density in perimysial connective tissue associated with prognosis in IMNM.

OBJECTIVE: The pathological features of immune-mediated necrotizing myopathy (IMNM) are dominated by the infiltration of macrophages. We aimed to perform a histopathologic semiquantitative analysis to investigate the relationship between macrophage markers and prognosis. METHODS: Semiquantitative analysis of histologic features was performed in 62 samples of IMNM. Independent risk factors were identified through univariate and multivariate regression analysis. Cluster analysis was performed using the partitioning around the medoids (PAM) method. Decision tree modeling was utilized to efficiently determine cluster labels for IMNM patients. The validity of the developmental cohort was assessed by accuracy in comparison with the validation cohort. RESULTS: The most enriched groups in patients with IMNM were macrophages expressing CD206 and CD163. In the multivariate logistic regression model, the high density of CD163+ macrophages in perimysial connective tissue increased the risk of unfavorable prognosis (p = 0.025, OR = 1.463, 95% CI: 1.049-2.041). In cluster analysis, patients in Cluster 1, with lower CD163+ macrophage density and inflammatory burden, had a more favorable prognosis. Conversely, patients in Cluster 3, which were enriched for CD163+ macrophages in the perimysial connective tissue, had the most severe clinical features and the worst prognosis. Correlations were found between the density of CD163+ macrophages in connective tissue and symptom duration (R2 = 0.166, p < 0.001), dysphagia (p = 0.004), cardiac involvement (p = 0.021), CK (R2 = 0.067, p = 0.042), CRP (R2 = 0.117, p < 0.001), and ESR (R2 = 0.171, p < 0.001). CONCLUSION: The density of CD163+ macrophages in perimysial connective tissue may serve as a potential marker for the prediction of IMNM prognosis.

Potential of neuroimaging as a biomarker in amyotrophic lateral sclerosis: from structure to metabolism.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease characterized by motor neuron degeneration. The development of ALS involves metabolite alterations leading to tissue lesions in the nervous system. Recent advances in neuroimaging have significantly improved our understanding of the underlying pathophysiology of ALS, with findings supporting the corticoefferent axonal disease progression theory. Current studies on neuroimaging in ALS have demonstrated inconsistencies, which may be due to small sample sizes, insufficient statistical power, overinterpretation of findings, and the inherent heterogeneity of ALS. Deriving meaningful conclusions solely from individual imaging metrics in ALS studies remains challenging, and integrating multimodal imaging techniques shows promise for detecting valuable ALS biomarkers. In addition to giving an overview of the principles and techniques of different neuroimaging modalities, this review describes the potential of neuroimaging biomarkers in the diagnosis and prognostication of ALS. We provide an insight into the underlying pathology, highlighting the need for standardized protocols and multicenter collaborations to advance ALS research.

Clinical-pathological features and muscle imaging findings in 36 Chinese patients with rimmed vacuolar myopathies: case series study and review of literature.

Introduction: Rimmed vacuolar myopathies (RVMs) are a group of genetically heterogeneous diseases that share histopathological characteristics on muscle biopsy, including the aberrant accumulation of autophagic vacuoles. However, the presence of non-coding sequences and structural mutations, some of which remain undetectable, confound the identification of pathogenic mutations responsible for RVMs. Therefore, we assessed the clinical profiles and muscle magnetic resonance imaging (MRI) changes in 36 Chinese patients with RVMs, emphasizing the role of muscle MRI in disease identification and differential diagnosis to propose a comprehensive literature-based imaging pattern to facilitate improved diagnostic workup. Methods: All patients presented with rimmed vacuoles with varying degrees of muscular dystrophic changes and underwent a comprehensive evaluation using clinical, morphological, muscle MRI and molecular genetic analysis. We assessed muscle changes in the Chinese RVMs and provided an overview of the RVMs, focusing on the patterns of muscle involvement on MRI. Results: A total of 36 patients, including 24 with confirmed distal myopathy and 12 with limb-girdle phenotype, had autophagic vacuoles with RVMs. Hierarchical clustering of patients according to the predominant effect of the distal or proximal lower limbs revealed that most patients with RVMs could be distinguished. GNE myopathy was the most prevalent form of RVMs observed in this study. Moreover, MRI helped identify the causative genes in some diseases (e.g., desminopathy and hereditary myopathy with early respiratory failure) and confirmed the pathogenicity of a novel mutation (e.g., adult-onset proximal rimmed vacuolar titinopathy) detected using next-generation sequencing. Discussion: Collectively, our findings expand our knowledge of the genetic spectrum of RVMs in China and suggest that muscle imaging should be an integral part of assisting genetic testing and avoiding misdiagnosis in the diagnostic workup of RVM.

The pathogenesis of anti-signal recognition particle necrotizing myopathy: A Review.

Immune-mediated necrotizing myopathy (IMNM) is a class of idiopathic inflammatory myopathies. According to the types of antibodies in serum, IMNM can be divided into three subtypes: anti-signal recognition particle (SRP) necrotizing myopathy, 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) necrotizing myopathy, and serum antibody-negative necrotizing myopathy. Different subtypes of IMNM have common characteristics, but the specific pathological mechanisms differ. Anti-SRP necrotizing myopathy is an important type of IMNM. At present, the pathogenesis of the disease is unclear. Most views suggest that the disease is mainly caused by an autoimmune response; therefore, the therapeutic strategy is primarily immune regulation. Recent studies have implicated non-immune mechanisms such as endoplasmic reticulum stress and autophagy in the occurrence and development of the disease. Here, we review what is known about the pathogenesis of anti-SRP necrotizing myopathy and summarize the latest research progress, aiming to better understand the disease and provide new ideas for treatment targets.

Inflammatory checkpoints in amyotrophic lateral sclerosis: From biomarkers to therapeutic targets.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron damage. Due to the complexity of the ALS, so far the etiology and underlying pathogenesis of sporadic ALS are not completely understood. Recently, many studies have emphasized the role of inflammatory networks, which are comprised of various inflammatory molecules and proteins in the pathogenesis of ALS. Inflammatory molecules and proteins may be used as independent predictors of patient survival and might be used in patient stratification and in evaluating the therapeutic response in clinical trials. This review article describes the latest advances in various inflammatory markers in ALS and its animal models. In particular, this review discusses the role of inflammatory molecule markers in the pathogenesis of the disease and their relationship with clinical parameters. We also highlight the advantages and disadvantages of applying inflammatory markers in clinical manifestations, animal studies, and drug clinical trials. Further, we summarize the potential application of some inflammatory biomarkers as new therapeutic targets and therapeutic strategies, which would perhaps expand the therapeutic interventions for ALS.

Next-Generation Sequencing Technologies and Neurogenetic Diseases.

Next-generation sequencing (NGS) technology has led to great advances in understanding the causes of Mendelian and complex neurological diseases. Owing to the complexity of genetic diseases, the genetic factors contributing to many rare and common neurological diseases remain poorly understood. Selecting the correct genetic test based on cost-effectiveness, coverage area, and sequencing range can improve diagnosis, treatments, and prevention. Whole-exome sequencing and whole-genome sequencing are suitable methods for finding new mutations, and gene panels are suitable for exploring the roles of specific genes in neurogenetic diseases. Here, we provide an overview of the classifications, applications, advantages, and limitations of NGS in research on neurological diseases. We further provide examples of NGS-based explorations and insights of the genetic causes of neurogenetic diseases, including Charcot-Marie-Tooth disease, spinocerebellar ataxias, epilepsy, and multiple sclerosis. In addition, we focus on issues related to NGS-based analyses, including interpretations of variants of uncertain significance, de novo mutations, congenital genetic diseases with complex phenotypes, and single-molecule real-time approaches.

A novel homozygous exon2 deletion of TRIM32 gene in a Chinese patient with sarcotubular myopathy: A case report and literature review.

Sarcotubular myopathy (STM) is a rare autosomal recessive myopathy caused by TRIM32 gene mutations. It is predominantly characterized by the weakness of the proximal limb and mild to moderate elevation of creatine kinase (CK) levels. In this study, we describe a 50-year-old Chinese man who exhibited a proximal-to-distal weakness in the muscles of the lower limbs and who had difficulty standing up from a squat position. The symptoms gradually became more severe. He denied a history of cognitive or cardiological problems. The patient's parents and children were healthy. Histopathological examination revealed dystrophic changes and irregular slit-shaped vacuoles containing amorphous materials. Whole-exome sequencing consisting of protein-encoding regions of 19,396 genes was performed, the results of which identified one novel homozygous 2kb deletion chr9.hg19: g.119460021_119461983del (exon2) in the TRIM32 gene. This was confirmed at the homozygous state with quantitative real-time PCR. Here, we present a Chinese case of STM with one novel mutation in TRIM32 and provide a brief summary of all known pathogenic mutations in TRIM32.

Neuronal intranuclear inclusion disease mimicking acute cerebellitis: A case report.

BACKGROUND: Neuronal intranuclear inclusion disease (NIID) is an unusual autosomal dominant, chronic progressive neurodegenerative disease. The clinical manifestations of NIID are complex and varied, complicating its clinical diagnosis. To the best of our knowledge, this report is the first to document sporadic adult-onset NIID mimicking acute cerebellitis (AC) that was finally diagnosed by imaging studies, skin biopsy, and genetic testing. CASE SUMMARY: A 63-year-old man presented with fever, gait unsteadiness, dysarthria, and an episode of convulsion. His serum levels of white blood cells and C-reactive protein were significantly elevated. T2-weighted brain magnetic resonance imaging and fluid attenuation inversion recovery sequences showed bilateral high-intensity signals in the medial part of the cerebellar hemisphere beside the vermis. While we initially considered a diagnosis of AC, the patient's symptoms improved significantly without special treatment, prompting our consideration of NIID. Diffusion-weighted imaging showed hyperintensity in the corticomedullary junction. Skin biopsy revealed eosinophilic inclusions positive for anti-p62 in epithelial sweat-gland cells. GGC repeat expansions in the Notch 2 N-terminal like C gene confirmed the diagnosis of NIID. CONCLUSION: For patients with clinical manifestations mimicking AC, the possibility of underlying NIID should be considered along with prompt rigorous examinations.

Adult-onset neuronal intranuclear inclusion disease mimicking Parkinson's disease in a Chinese patient: a case report and literature reviews.

Neuronal intranuclear inclusion disease is a rare hereditary neurodegenerative disease characterized by localized eosinophilic intracytoplasmic inclusion bodies in cells of the nervous system and internal organs. This disorder is frequently missed or misdiagnosed, as there is significant heterogeneity of its clinical presentation. Recently, genetic sequencing has revealed complex links between neuronal intranuclear inclusion disease and other neurodegenerative diseases, potentially explaining the diversity of clinical manifestations. Herein, we describe the case of a 68-year-old male Chinese patient who was initially diagnosed with Parkinson's disease based on classic symptomatology and ¹²³I-metaiodobenzylguanidine scintigraphy results and was subsequently treated with oral methyldopa for 3 years. He developed a paroxysmal tic before he presented to our hospital for treatment after a convulsive seizure. Brain magnetic resonance imaging identified signal hyperintensity at the corticomedullary junction on diffusion-weighted imaging. Skin biopsy results and genetic testing confirmed a revised diagnosis of neuronal intranuclear inclusion disease. This report highlights that patients clinically diagnosed with Parkinson's disease may actually be in the early stages of neuronal intranuclear inclusion disease, suggesting that patients with suspected Parkinson's disease should also be screened for this disease.

A case report: identification of a novel exon 1 deletion mutation in the GNE gene in a Chinese patient with GNE myopathy.

RATIONALE: GNE myopathy is caused by mutations in the UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase(GNE) gene and is clinically characterized by progressive weakness and atrophy of the lower-limb muscles with quadriceps sparing. Nearly all GNE mutations that have been reported thus far in various ethnic populations around the world have been missense or nonsense mutations. PATIENT CONCERNS: We describe the case of a 32-year-old woman with GNE myopathy. The patient presented with progressive weakness of the lower-limb muscles that had spread to her legs. Her serum creatine kinase level was higher than the normal range. Mild myogenic changes were detected in the tibialis anterior muscles on electromyography, and moderate fatty infiltration was observed in various lower-limb muscles on magnetic resonance imaging. Histopathological examination of a skeletal muscle biopsy specimen revealed variation in muscle fiber size, rimmed vacuoles, and disorganized intermyofibrillar networks. DNA sequencing testing revealed a compound heterozygous mutation consisting of a known mutation (c.620A > T in exon 3) and a novel (exon 1 deletion) mutation. DIAGNOSES: Taken together, the clinical features, laboratory testing and DNA findings eventually made the diagnosis of GNE myopathy. INTERVENTIONS AND OUTCOMES: Based on the diagnosis of the GNE myopathy, the patient was administered sialic acid 6 g a day for 1 year, and up to now, her symptoms did not progress further. LESSONS: We have reported the case of a GNE myopathy patient with compound heterozygous GNE gene mutations. This case expands the genotypic spectrum of GNE myopathy.

Acute bilateral cerebral infarction in the presence of neuromyelitis optica spectrum disorder: A case report.

RATIONALE: Neuromyelitis optica spectrum disorders (NMOSDs) are inflammatory demyelinating disorders of the central nervous system; they are characterized by severe optic neuritis and transverse myelitis. Intravenous methylprednisolone pulse (IVMP) therapy is an effective treatment that is administered to patients in the acute phase of NMOSD; this therapy has achieved remarkable results in clinical practice. However, there are no reports on NMOSD patients who have experienced an acute bilateral cerebral infarction while undergoing IVMP treatment. PATIENT CONCERNS: We report on a 62-yr-old woman who was undergoing IVMP therapy for the primary diagnosis of NMOSD. Unexpectedly, the patient's existing limb weakness worsened, and she developed motor aphasia on the second day of IVMP treatment. Additionally, brain magnetic resonance imaging revealed acute bilateral cerebral infarction. DIAGNOSIS: The patient's clinical manifestations, medical imaging results, and laboratory test results were taken into consideration; the final diagnosis was acute bilateral cerebral infarction in the presence of NMOSD. INTERVENTIONS: Subsequent to the onset of acute cerebral infarction, the patient was immediately treated with oral aspirin, atorvastatin, and intravenous butylphthalide. The hormone dose was adjusted to an oral 60-mg/d dose for maintenance; this was followed by immunoadsorption plasmapheresis for 3 days, and double-filtration plasmapheresis for 2 days. OUTCOMES: Following treatment onset, the patient's ocular symptoms significantly improved, and her limb muscle strength gradually recovered. Two months after discharge, the patient's husband reported that she was able to walk with the help of others and take care of herself, and that there was no recurrence. LESSONS: Medical professionals must be aware of the possibility of NMOSD patients with cerebrovascular risk factors suffering an acute cerebral infarction while undergoing high-dose IVMP therapy, as this therapy can exacerbate existing problems.

Complete spinal cord involvement from neuromyelitis optica spectrum disorder in an adult female with anti-synthetase syndrome.

Anti-synthetase syndrome (ASS) is a rare autoimmune disorder characterized by the presence of antibodies against aminoacyl-transfer RNA synthetase commonly associated inflammatory myopathy. In this case report, we describe an adult female with NMOSD concurrent with ASS in which the lesion involved the entire length of the spinal cord. Since B-cell mediated molecular pathway is involved in the pathogenesis of NMOSD and ASS, we suggest that the therapeutically targeted killing of B-cells, such as Rituximab, is effective.

A family with nemaline myopathy type 6 caused by hseterozygous mutation (c.1222C>T) in the KBTBD13 gene in China: A case report.

Nemaline myopathy (NEM) is a congenital myopathy that typically presents with proximal muscle weakness and hypotonia. To date, 13 genes have been associated with NEM. The Kelch repeat and BTB domain-containing protein 13 (KBTBD13) gene (KBTBD13)-related NEM is a rarely reported condition, and not a single case has been reported in Asia. Here, we report the case of a mother and daughter in China with NEM caused by a mutation (c.1222C>T) in KBTBD13. Their shared clinical phenotype is symmetrical muscle weakness in the arms and legs with childhood onset. Muscle magnetic resonance imaging showed the unique replacement mode of muscle with fibro-fatty tissue. Histopathological examination revealed the presence of fibers containing rod-shaped structures in the cytoplasm or under the sarcolemma. DNA sequencing analysis detected a heterozygous mutation (c.1222C>T) in KBTBD13 in this family. A founder effect for the variant may exist in the Low Countries of Belgium and the Netherlands, and the mutation may be a hotspot mutation in Europe, as it has not been reported in Asia. Our case study expands the spectrum of KBTBD13-related NEM.

A case report: autosomal recessive Myotonia congenita caused by a novel splice mutation (c.1401 + 1G > A) in CLCN1 gene of a Chinese Han patient.

BACKGROUND: Autosomal recessive Myotonia congenita (Becker's disease) is caused by mutations in the CLCN1 gene. The condition is characterized by muscle stiffness during sustained muscle contraction and variable degree of muscle weakness that tends to improve with repeated contractions. CASE PRESENTATION: A 21-year-old man presented with transient muscle stiffness since the last 10 years. He had difficulty in initiating movement and experienced muscle weakness after rest, which typically improved after repeated contraction (warm-up phenomenon). There was no significant family history. Medical examination showed generalized muscle hypertrophy. Serum creatine kinase level was 2-fold higher than the normal value. Electromyogram showed myotonic discharges. DNA sequence analysis identified a novel splice mutation (c.1401 + 1G > A) and a known mutation (c.1657A > T,p.Ile553Phe). He rapidly responded to treatment with mexiletine 100 mg three times a day for 6 months. CONCLUSIONS: This case report of autosomal recessive Myotonia congenita caused by a novel compound heterozygous mutation expands the genotypic spectrum of CLCN1 gene.

A case report: a heterozygous deletion (2791_2805 del) in exon 18 of the filamin C gene causing filamin C-related myofibrillar myopathies in a Chinese family.

BACKGROUND: Filamin C-related myofibrillar myopathies (MFM) are progressive skeletal myopathies with an autosomal dominant inheritance pattern. The conditions are caused by mutations of the filamin C gene (FLNC) located in the chromosome 7q32-q35 region. Genetic variations in the FLNC gene result in various clinical phenotypes. CASE PRESENTATION: We describe a 43-year-old woman who suffered filamin C-related MFM, with symptoms first presenting in the proximal muscles of the lower limbs and eventually spreading to the upper limbs and distal muscles. The patient's serum level of creatine kinase was mildly increased. Mildy myopathic changes in the electromyographic exam and moderate lipomatous alterations in lower limb MRI were found. Histopathological examination revealed increased muscle fiber size variability, disturbances in oxidative enzyme activity, and the presence of abnormal protein aggregates and vacuoles in some muscle fibers. Ultrastructural analysis showed inclusions composed of thin filaments and interspersed granular densities. DNA sequencing analysis detected a novel 15-nucleotide deletion (c.2791_2805del, p.931_935del) in the FLNC gene. The patient's father, sister, brother, three paternal aunts, one paternal uncle, and the uncle's son also had slowly progressive muscle weakness, and thus, we detected an autosomal dominant inheritance pattern of the disorder. CONCLUSIONS: A novel heterogeneous 15-nucleotide deletion (c.2791_2805del, p.931_935del) in the Ig-like domain 7 of the FLNC gene was found to cause filamin C-related MFM. This deletion in the FLNC gene causes protein aggregation, abnormalities in muscle structure, and impairment in muscle fiber function, which leads to muscle weakness.

A case report: Becker muscular dystrophy presenting with epilepsy and dysgnosia induced by duplication mutation of Dystrophin gene.

BACKGROUND: Becker muscular dystrophy (BMD), a genetic disorder of X-linked recessive inheritance, typically presents with gradually progressive muscle weakness. The condition is caused by mutations of Dystrophin gene located at Xp21.2. Epilepsy is an infrequent manifestation of BMD, while cases of BMD with dysgnosia are extremely rare. CASE PRESENTATION: We describe a 9-year-old boy with BMD, who presented with epilepsy and dysgnosia. Serum creatine kinase level was markedly elevated (3665 U/L). Wechsler intelligence tests showed a low intelligence quotient (IQ = 65). Electromyogram showed slight myogenic changes and skeletal muscle biopsy revealed muscular dystrophy. Immunohistochemical staining showed partial positivity of sarcolemma for dystrophin-N. Multiplex ligation-dependent probe amplification revealed a duplication mutation in exons 37-44 in the Dystrophin gene. CONCLUSIONS: The present case report helps to better understand the clinical and genetic features of BMD.

Let-7a gene knockdown protects against cerebral ischemia/reperfusion injury.

The microRNA (miRNA) let-7 was one of the first miRNAs to be discovered, and is highly conserved and widely expressed among species. let-7 expression increases in brain tissue after cerebral ischemia/reperfusion injury; however, no studies have reported let-7 effects on nerve injury after cerebral ischemia/reperfusion injury. To investigate the effects of let-7 gene knockdown on cerebral ischemia/reperfusion injury, we established a rat model of cerebral ischemia/reperfusion injury. Quantitative reverse transcription-polymerase chain reaction demonstrated that 12 hours after cerebral ischemia/reperfusion injury, let-7 expression was up-regulated, peaked at 24 hours, and was still higher than that in control rats after 72 hours. Let-7 gene knockdown in rats suppressed microglial activation and inflammatory factor release, reduced neuronal apoptosis and infarct volume in brain tissue after cerebral ischemia/reperfusion injury. Western blot assays and luciferase assays revealed that mitogen-activated protein kinase phosphatase-1 (MKP1) is a direct target of let-7. Let-7 enhanced phosphorylated p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) expression by down-regulating MKP1. These findings suggest that knockdown of let-7 inhibited the activation of p38 MAPK and JNK signaling pathways by up-regulating MKP1 expression, reduced apoptosis and the inflammatory reaction, and exerted a neuroprotective effect following cerebral ischemia/reperfusion injury.

Muscle biopsy and UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase gene mutation analysis in two Chinese patients with distal myopathy with rimmed vacuoles.

Distal myopathy with rimmed vacuoles is an autosomal recessive genetic disease characterized by weakness of the anterior compartment of the lower limbs, sparing the quadriceps muscle, and rimmed vacuoles in muscle biopsies. The disease is caused by a mutation in the UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) gene located on chromosome 9p13.3. We present two cases of Chinese patients with progressive lower extremity weakness. Clinical presentation, laboratory evaluation, electrodiagnostic testing, muscle pathology, and genetic analysis are described. Patient 1 was found to have heterozygous missense mutations (p.C13S and p.G576R) in the GNE gene and patient 2 had a homozygous missense mutation (p.C13S). The mutation p.C13S has been reported previously in China, Japan, and South Korea; however, the mutation p.G576R has not been described previously.

Myoclonic epilepsy with ragged-red fibers: A case report.

Myoclonic epilepsy with ragged-red fibers is a maternally inherited disease that is characterized by myoclonic epilepsy, cerebellar ataxia and progressive muscular weakness. The present study reports the case of a 25-year-old male who presented with paroxysmal left upper limb tics and weakness for two years. Neurological examination revealed intact cranial nerves, decreased deep tendon reflexes and decreased sensation of touch, pain and vibration. The gait of the patient was broad and he was unable to walk in a straight line. Local cortical atrophy was also observed in the left temporal-occipital cortex on a magnetic resonance imaging scan. The muscle biopsy revealed ragged-red fibers. Therefore, the present study hypothesized that imaging observations and follow-up examinations are important in patients with myoclonic epilepsy.