Correction of human nonsense mutation via adenine base editing for Duchenne muscular dystrophy treatment in mouse

Duchenne muscular dystrophy (DMD) is the most prevalent herediatry disease in men, characterized by dystrophin deficiency, progressive muscle wasting, cardiac insufficiency, and premature mortality, with no effective therapeutic options. Here, we investigated whether adenine base editing can correct pathological nonsense point mutations leading to premature stop codons in the dystrophin gene. We identified 27 causative nonsense mutations in our DMD patient cohort. Treatment with adenine base editor (ABE) could restore dystrophin expression by direct A-to-G editing of pathological nonsense mutations in cardiomyocytes generated from DMD patient-derived induced pluripotent stem cells. We also generated two humanized mouse models of DMD expressing mutation-bearing exons 23 or 30 of human dystrophin gene. Intramuscular administration of ABE, driven by ubiquitous or muscle-specific promoters could correct these nonsense mutations in vivo, albeit with higher efficiency in exon 30, restoring dystrophin expression in skeletal fibers of humanized DMD mice. Moreover, a single systemic delivery of ABE with human single guide RNA (sgRNA) could induce body-wide dystrophin expression and improve muscle function in rotarod tests of humanized DMD mice. These findings demonstrate that ABE with human sgRNAs can confer therapeutic alleviation of DMD in mice, providing a basis for development of adenine base editing therapies in monogenic diseases.

Inflammation Triggers Chondrocyte Ferroptosis in TMJOA via HIF-1α/TFRC

Inflammation and loss of articular cartilage are considered the major cause of temporomandibular joint osteoarthritis (TMJOA), a painful condition of the temporomandibular joint (TMJ). To determine the cause of TMJ osteoarthritis in these patients, synovial fluid of TMJOA patients was compared prior to and after hyaluronic lavage, revealing substantially elevated levels of interleukin (IL) 1β, reactive oxidative stress (ROS), and an overload of Fe3+ and Fe2+ prior to lavage, indicative of ferroptosis as a mode of chondrocyte cell death. To ask whether prolonged inflammatory conditions resulted in ferroptosis-like transformation in vitro, we subjected TMJ chondrocytes to IL-1β treatment, resulting in a shift in messenger RNA sequencing gene ontologies related to iron homeostasis and oxidative stress-related cell death. Exposure to rat unilateral anterior crossbite conditions resulted in reduced COL2A1 expression, fewer chondrocytes, glutathione peroxidase 4 (GPX4) downregulation, and 4-hydroxynonenal (4-HNE) upregulation, an effect that was reversed after intra-articular injections of the ferroptosis inhibitor ferrostatin 1 (Fer-1). Our study demonstrated that ferroptosis conditions affected mitochondrial structure and function, while the inhibitor Fer-1 restored mitochondrial structure and the inhibition of hypoxia-inducible factor 1α (HIF-1α) or the transferrin receptor 1 (TFRC) rescued IL-1β-induced loss of mitochondrial membrane potential. Inhibition of HIF-1α downregulated IL-1β-induced TFRC expression, while inhibition of TFRC did not downregulate IL-1β-induced HIF-1α expression in chondrocytes. Moreover, inhibition of HIF-1α or TFRC downregulated the IL-1β-induced MMP13 expression in chondrocytes, while inhibition of HIF-1α or TFRC rescued IL-1β-inhibited COL2A1 expression in chondrocytes. Furthermore, upregulation of TFRC promoted Fe2+ entry into chondrocytes, inducing the Fenton reaction and lipid peroxidation, which in turn caused ferroptosis, a disruption in chondrocyte functions, and an exacerbation of condylar cartilage degeneration. Together, these findings illustrate the far-reaching effects of chondrocyte ferroptosis in TMJOA as a mechanism causing chondrocyte death through iron overload, oxidative stress, and articular cartilage degeneration and a potential major cause of TMJOA.

Detection of pTDP-43 via routine muscle biopsy: A promising diagnostic biomarker for amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease, pathologically characterized by TDP-43 aggregates. Recent evidence has been indicated that phosphorylated TDP-43 (pTDP-43) is present not only in motor neurons but also in muscle tissues. However, it is unclear whether testing pTDP-43 aggregation in muscle tissue would assist in the diagnosis of ALS. We propose three key questions: (i) Is aggregation of pTDP-43 detectable in routine biopsied muscles? (ii) Can detection of pTDP-43 aggregation discriminate between ALS and non-ALS patients? (iii) Can pTDP-43 aggregation be observed in the early stages of ALS? We conducted a diagnostic study comprising 2 groups: an ALS group in which 18 cases underwent muscle biopsy screened from a registered ALS cohort consisting of 802 patients and a non-ALS control group, in which we randomly selected 54 muscle samples from a biospecimen bank of 684 patients. Among the 18 ALS patients, 3 patients carried pathological GGGGCC repeats in the C9ORF72 gene, 2 patients carried SOD1 mutations, and 7 patients were at an early stage with only one body region clinically affected. The pTDP-43 accumulation could be detected in routine biopsied muscles, including biceps brachii, deltoid, tibialis anterior, and quadriceps. Abnormal aggregation of pTDP-43 was present in 94.4% of ALS patients (17/18) compared to 29.6% of non-ALS controls (16/54; p < 0.001). The pTDP-43 aggregates were mainly close to the sarcolemma. Using a semi-quantified pTDP-43 aggregates score, we applied a cut-off value of 3 as a diagnostic biomarker, resulting in a sensitivity of 94.4% and a specificity of 83.3%. Moreover, we observed that accumulation of pTDP-43 occurred in muscle tissues prior to clinical symptoms and electromyographic lesions. Our study provides proof-of-concept for the detection of pTDP-43 accumulation via routine muscle biopsy which may serve as a novel biomarker for diagnosis of ALS.

CGG repeat expansion in LOC642361/NUTM2B-AS1 typically presents as oculopharyngodistal myopathy

CGG repeat expansions in LOC642361/NUTM2B-AS1 have recently been identified as a cause of oculopharyngeal myopathy with leukoencephalopathy. However, since only three patients from a single family were reported, it remains unknown whether their clinicopathological features are typical for CGG repeat expansions in LOC642361/NUTM2B-AS1. Here, using repeat-primed-polymerase chain reaction and long-read sequencing, we identify 12 individuals from 3 unrelated families with CGG repeat expansions in LOC642361/NUTM2B-AS1, typically presenting with oculopharyngodistal myopathy. The CGG repeat expansions range from 161 to 669 repeat units. Most of the patients present with ptosis, restricted eye movements, dysphagia, dysarthria, and diffuse limb muscle weakness. Only one patient shows T2-weighted hyperintensity in the cerebellar white matter surrounding the deep cerebellar nuclei on brain magnetic resonance imaging. Muscle biopsies from three patients show a myopathic pattern and rimmed vacuoles. Analyses of muscle biopsies suggest that CGG repeat expansions in LOC642361/NUTM2B-AS1 may deleteriously affect aggrephagic capacity, suggesting that RNA toxicity and mitochondrial dysfunction may contribute to pathogenesis. Our study thus expands the phenotypic spectrum for the CGG repeat expansion of LOC642361/NUTM2B-AS1 and indicates that this genetic variant typically manifests as oculopharyngodistal myopathy with chronic myopathic changes with rimmed vacuoles and filamentous intranuclear inclusions in muscle fibers.

Cognitive impairment associated with cerebellar volume loss in spinocerebellar ataxia type 3

BACKGROUND

Many neuroscience and neurology studies have forced a reconsideration of the traditional motor-related scope of cerebellar function, which has now expanded to include various cognitive functions. Spinocerebellar ataxia type 3 (SCA3; the most common hereditary ataxia) is neuropathologically characterized by cerebellar atrophy and frequently presents with cognitive impairment.

OBJECTIVE

To characterize cognitive impairment in SCA3 and investigate the cerebellum-cognition associations.

METHODS

This prospective, cross-sectional cohort study recruited 126 SCA3 patients and 41 healthy control individuals (HCs). Participants underwent a brain 3D T1-weighted images as well as neuropsychological tests. Voxel-based morphometry (VBM) and region of interest (ROI) approaches were performed on the 3D T1-weighted images. CERES was used to automatically segment cerebellums. Patients were grouped into cognitively impaired (CI) and cognitively preserved (CP), and clinical and MRI parameters were compared. Multivariable regression models were fitted to examine associations between cerebellar microstructural alterations and cognitive domain impairments.

RESULTS

Compared to HCs, SCA3 patients showed cognitive domain impairments in information processing speed, verbal memory, executive function, and visuospatial perception. Between CI and CP subgroups, the CI subgroup was older and had lower education, as well as higher severity scores. VBM and ROI analyses revealed volume loss in cerebellar bilateral lobule VI, right lobule Crus I, and right lobule IV of the CI subgroup, and all these cerebellar lobules were associated with the above cognitive domain impairments.

CONCLUSIONS

Our findings demonstrate the multiple cognitive domain impairments in SCA3 patients and indicate the responsible cerebellar lobules for the impaired cognitive domain(s).

Biallelic COQ4 Variants in Hereditary Spastic Paraplegia: Clinical and Molecular Characterization

BACKGROUND

Hereditary spastic paraplegias (HSP) are neurologic disorders characterized by progressive lower-extremity spasticity. Despite the identification of several HSP-related genes, many patients lack a genetic diagnosis.

OBJECTIVES

The aims were to confirm the pathogenic role of biallelic COQ4 mutations in HSP and elucidate the clinical, genetic, and functional molecular features of COQ4-associated HSP.

METHODS

Whole exome sequences of 310 index patients with HSP of unknown cause from three distinct populations were analyzed to identify potential HSP causal genes. Clinical data obtained from patients harboring candidate causal mutations were examined. Functional characterization of COQ4 variants was performed using bioinformatic tools, single-cell RNA sequencing, biochemical assays in cell lines, primary fibroblasts, induced pluripotent stem cell-derived pyramidal neurons, and zebrafish.

RESULTS

Compound heterozygous variants in COQ4, which cosegregated with HSP in pedigrees, were identified in 7 patients from six unrelated families. Patients from four of the six families presented with pure HSP, whereas probands of the other two families exhibited complicated HSP with epilepsy or with cerebellar ataxia. In patient-derived fibroblasts and COQ4 knockout complementation lines, stable expression of these missense variants exerted loss-of-function effects, including mitochondrial reactive oxygen species accumulation, decreased mitochondrial membrane potential, and lower ubiquinone biosynthesis. Whereas differentiated pyramidal neurons expressed high COQ4 levels, coq4 knockdown zebrafish displayed severe motor dysfunction, reflecting motor neuron dysregulation.

CONCLUSIONS

Our study confirms that loss-of-function, compound heterozygous, pathogenic COQ4 variants are causal for autosomal recessive pure and complicated HSP. Moreover, reduced COQ4 levels attributable to variants correspond with decreased ubiquinone biosynthesis, impaired mitochondrial function, and higher phenotypic disease severity. © 2023 International Parkinson and Movement Disorder Society.

Alu Retrotransposition Event in SPAST Gene as a Novel Cause of Hereditary Spastic Paraplegia

OBJECTIVES

To diagnose the molecular cause of hereditary spastic paraplegia (HSP) observed in a four-generation family with autosomal dominant inheritance.

METHODS

Multiplex ligation-dependent probe amplification (MLPA), whole-exome sequencing (WES), and RNA sequencing (RNA-seq) of peripheral blood leukocytes were performed. Reverse transcription polymerase chain reaction (RT-PCR) and Sanger sequencing were used to characterize target regions of SPAST.

RESULTS

A 121-bp AluYb9 insertion with a 30-bp poly-A tail flanked by 15-bp direct repeats on both sides was identified in the edge of intron 16 in SPAST that segregated with the disease phenotype.

CONCLUSIONS

We identified an intronic AluYb9 insertion inducing splicing alteration in SPAST causing pure HSP phenotype that was not detected by routine WES analysis. Our findings suggest RNA-seq is a recommended implementation for undiagnosed cases by first-line diagnostic approaches. © 2023 International Parkinson and Movement Disorder Society.

[Clinical features of post-neurosurgical bacterial meningitis in children]

Objective: To understand the characteristics of bacterial meningitis after pediatric neurosurgical procedures. Methods: This was a retrospective observational study. From January 2016 to December 2022, 64 children diagnosed with post-neurosurgical bacterial meningitis based on positive cerebrospinal fluid (CSF) culture in Department of Neurosurgery of Shanghai Children's Medical Center were selected as the study population. The clinical characteristics, onset time, routine biochemical indexes of cerebrospinal fluid before anti infection treatment, bacteriology characteristics and sensitivity to antibiotics of bacteria cultured from cerebrospinal fluid were analyzed. Based on the CSF culture results, the patients were divided into the Gram-positive bacteria infection group and the Gram-negative bacteria infection group. The clinical characteristics of the two groups were compared using t-tests or Wilcoxon rank-sum tests, and chi-square tests. Results: There were 64 children,42 boys and 22 girls, with onset age of 0.83 (0.50, 1.75) years. Seventy cases of post-neurosurgical bacterial meningitis occurred in the 64 children, of which 15 cases (21%) in spring, 23 cases (33%) in summer, 19 cases (27%) in autumn, and 13 cases (19%) in winter. The time of onset was 3.5 (1.0, 10.0) months after surgery; 15 cases (21%) occurred within the first month after the surgery, and 55 cases (79%) occurred after the first month. There were 38 cases (59%) showing obvious abnormal clinical manifestations, fever 36 cases (56%), vomiting 11 cases (17%). Forty-eight cases (69%) were caused by Gram-positive bacteria, with Staphylococcus epidermidis 24 cases; 22 cases (31%) were caused by Gram-negative bacteria, with Acinetobacter baumannii the prominent pathogen 7 cases. The Gram-positive bacterial infection was more common in summer than the Gram-negative bacterial infection (20 cases (42%) vs. 3 cases (14%), χ²=5.37, P=0.020), while the Gram-negative bacterial infection was more in autumn and within the first month after surgery than the Gram-positive bacterial infection (11 cases (50%) vs. 8 cases (17%), 15 cases (67%) vs. 5 cases (33%), χ²=8.48, 9.02; P=0.004, 0.003). Gram-positive bacteria resistant to vancomycin and Acinetobacter baumannii resistant to polymyxin were not found. However, Acinetobacter baumannii showed only 45% (10/22) susceptibility to carbapenem antibiotics. Conclusions: The clinical presentation of post-neurosurgical bacterial meningitis in children is atypical. Gram-positive bacteria are the main pathogens causing post-neurosurgical bacterial meningitis; Gram-negative bacterial meningitis are more likely to occur in autumn and within the first month after surgery. Acinetobacter baumannii has a high resistance rate to carbapenem antibiotics, which should be taken seriously.

[Expert consensus on late stage of critical care management]

We wished to establish an expert consensus on late stage of critical care (CC) management. The panel comprised 13 experts in CC medicine. Each statement was assessed based on the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) principle. Then, the Delphi method was adopted by 17 experts to reassess the following 28 statements. (1) ESCAPE has evolved from a strategy of delirium management to a strategy of late stage of CC management. (2) The new version of ESCAPE is a strategy for optimizing treatment and comprehensive care of critically ill patients (CIPs) after the rescue period, including early mobilization, early rehabilitation, nutritional support, sleep management, mental assessment, cognitive-function training, emotional support, and optimizing sedation and analgesia. (3) Disease assessment to determine the starting point of early mobilization, early rehabilitation, and early enteral nutrition. (4) Early mobilization has synergistic effects upon the recovery of organ function. (5) Early functional exercise and rehabilitation are important means to promote CIP recovery, and gives them a sense of future prospects. (6) Timely start of enteral nutrition is conducive to early mobilization and early rehabilitation. (7) The spontaneous breathing test should be started as soon as possible, and a weaning plan should be selected step-by-step. (8) The waking process of CIPs should be realized in a planned and purposeful way. (9) Establishment of a sleep-wake rhythm is the key to sleep management in post-CC management. (10) The spontaneous awakening trial, spontaneous breathing trial, and sleep management should be carried out together. (11) The depth of sedation should be adjusted dynamically in the late stage of CC period. (12) Standardized sedation assessment is the premise of rational sedation. (13) Appropriate sedative drugs should be selected according to the objectives of sedation and drug characteristics. (14) A goal-directed minimization strategy for sedation should be implemented. (15) The principle of analgesia must be mastered first. (16) Subjective assessment is preferred for analgesia assessment. (17) Opioid-based analgesic strategies should be selected step-by-step according to the characteristics of different drugs. (18) There must be rational use of non-opioid analgesics and non-drug-based analgesic measures. (19) Pay attention to evaluation of the psychological status of CIPs. (20) Cognitive function in CIPs cannot be ignored. (21) Delirium management should be based on non-drug-based measures and rational use of drugs. (22) Reset treatment can be considered for severe delirium. (23) Psychological assessment should be conducted as early as possible to screen-out high-risk groups with post-traumatic stress disorder. (24) Emotional support, flexible visiting, and environment management are important components of humanistic management in the intensive care unit (ICU). (25) Emotional support from medical teams and families should be promoted through"ICU diaries"and other forms. (26) Environmental management should be carried out by enriching environmental content, limiting environmental interference, and optimizing the environmental atmosphere. (27) Reasonable promotion of flexible visitation should be done on the basis of prevention of nosocomial infection. (28) ESCAPE is an excellent project for late stage of CC management.

Heterozygous Seryl-tRNA Synthetase 1 Variants Cause Charcot-Marie-Tooth Disease

OBJECTIVE

Despite the increasing number of genes associated with Charcot-Marie-Tooth (CMT) disease, many patients currently still lack appropriate genetic diagnosis for this disease. Autosomal dominant mutations in aminoacyl-tRNA synthetases (ARSs) have been implicated in CMT. Here, we describe causal missense mutations in the gene encoding seryl-tRNA synthetase 1 (SerRS) for 3 families affected with CMT.

METHODS

Whole-exome sequencing was performed in 16 patients and 14 unaffected members of 3 unrelated families. The functional impact of the genetic variants identified was investigated using bioinformatic prediction tools and confirmed using cellular and biochemical assays.

RESULTS

Combined linkage analysis for the 3 families revealed significant linkage (Zmax LOD = 6.9) between the genomic co-ordinates on chromosome 1: 108681600-110300504. Within the linkage region, heterozygous SerRS missense variants segregated with the clinical phenotype in the 3 families. The mutant SerRS proteins exhibited reduced aminoacylation activity and abnormal SerRS dimerization, which suggests the impairment of total protein synthesis and induction of eIF2α phosphorylation.

INTERPRETATION

Our findings suggest the heterozygous SerRS variants identified represent a novel cause for autosomal dominant CMT. Mutant SerRS proteins are known to impact various molecular and cellular functions. Our findings provide significant advances on the current understanding of the molecular mechanisms associated with ARS-related CMT. ANN NEUROL 2023;93:244-256.

Implication of Cerebral Small-Vessel Disease on Perihematomal Edema Progress in Patients With Hypertensive Intracerebral Hemorrhage

BACKGROUND

Perihematomal edema (PHE) is an important determinant of outcome in spontaneous intracerebral hemorrhage (ICH) due to cerebral small vessel disease (CSVD). However, it is not known to date whether the severity of CSVD is associated with the extent of PHE progression in the acute phase.

PURPOSE

To investigate the association between the magnetic resonance imaging (MRI) marker of severe chronic-ischemia cerebral small vessel changes (sciSVC) and PHE growth or hematoma absorption among ICH patients with hypertension.

STUDY TYPE

Retrospective.

POPULATION

Three hundred and sixty-eight consecutive hypertensive ICH patients without surgical treatment.

FIELD STRENGTH/SEQUENCE

3 T; spin-echo echo-planar imaging-diffusion-weighted imaging (DWI); T2-weighted, fluid-attenuated inversion recovery (FLAIR), T2*-weighted gradient-recalled echo and T1-weighted.

ASSESSMENT

The hematoma and PHE volumes at 24 hours and 5 days after symptom onset were measured in 121 patients with spontaneous ICH who had been administered standard medical treatment. Patients were grouped into two categories: those with sciSVC and those without. The imaging marker of sciSVC was defined as white matter hyperintensities (WMHs) Fazekas 2-3 combined cavitating lacunes.

STATISTICAL TESTS

Univariable analyses, χ² test, Mann-Whitney U test, and multiple linear regression.

RESULTS

The presence of sciSVC (multiple lacunes and confluent WMH) had a significant negative influence on PHE progress (Beta = -5.3 mL, 95% CI = -10.3 mL to -0.3 mL), and hematoma absorption (Beta = -3.2 mL, 95% CI = -5.9 mL to -0.4 mL) compared to that observed in the absence of sciSVC, as determined by multivariate linear regression analysis.

DATA CONCLUSIONS

The presence of sciSVC (multiple lacunes and confluent WMH) negatively influenced hematoma absorption and PHE progress in ICH patients.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 3.

Short-term efficacy of repetitive transcranial magnetic stimulation in SCA3: A prospective, randomized, double-blind, sham-controlled study

OBJECTIVE

Spinocerebellar ataxia type 3 (SCA3) is the most common autosomal dominant ataxia globally. No effective treatment is currently available for SCA3. Repetitive Transcranial Magnetic Stimulation (rTMS) is a non-invasive form of brain stimulation, demonstrated to improve symptoms in patients with neurodegenerative cerebellar ataxias. The present study investigated whether treatment with rTMS over the cerebellum for 15 consecutive days improved measures of ataxia in SCA3 patients.

METHODS

A double-blind, prospective, randomized, sham-controlled trial was carried out on 44 SCA3 patients. Participants were randomly assigned to two groups: real or sham stimulation. Each participant underwent 30 minutes of 1Hz rTMS stimulation (a total of 900 pulses) for 15 consecutive days. The primary outcome measure was the score on the International Cooperative Ataxia Rating Scale (ICARS), and secondary outcomes were from the Scale for the Assessment and Rating of Ataxia (SARA) and the Berg Balance Scale (BBS).

RESULTS

Nausea was the only adverse effect reported by 2 participants from the sham and real group. After 15 days of treatment, there was a significant improvement in all performance scores in both real and sham stimulation groups. However, compared to the sham group, the improvements were significantly larger in the real group for the ICARS (P = 0.002), SARA (P = 0.001), and BBS (P = 0.001).

INTERPRETATION

A 15 days treatment with rTMS over the cerebellum improves the symptoms of ataxia in SCA3 patients. Our results suggest that rTMS is a promising tool for future rehabilitative approaches in SCA3.

Knockdown of myorg leads to brain calcification in zebrafish

Primary familial brain calcification (PFBC) is a neurogenetic disorder characterized by bilateral calcified deposits in the brain. We previously identified that MYORG as the first pathogenic gene for autosomal recessive PFBC, and established a Myorg-KO mouse model. However, Myorg-KO mice developed brain calcifications until nine months of age, which limits their utility as a facile PFBC model system. Hence, whether there is another typical animal model for mimicking PFBC phenotypes in an early stage still remained unknown. In this study, we profiled the mRNA expression pattern of myorg in zebrafish, and used a morpholino-mediated blocking strategy to knockdown myorg mRNA at splicing and translation initiation levels. We observed multiple calcifications throughout the brain by calcein staining at 2–4 days post-fertilization in myorg-deficient zebrafish, and rescued the calcification phenotype by replenishing myorg cDNA. Overall, we built a novel model for PFBC via knockdown of myorg by antisense oligonucleotides in zebrafish, which could shorten the observation period and replenish the Myorg-KO mouse model phenotype in mechanistic and therapeutic studies.

Loss of function of CMPK2 causes mitochondria deficiency and brain calcification

Brain calcification is a critical aging-associated pathology and can cause multifaceted neurological symptoms. Cerebral phosphate homeostasis dysregulation, blood-brain barrier defects, and immune dysregulation have been implicated as major pathological processes in familial brain calcification (FBC). Here, we analyzed two brain calcification families and identified calcification co-segregated biallelic variants in the CMPK2 gene that disrupt mitochondrial functions. Transcriptome analysis of peripheral blood mononuclear cells (PBMCs) isolated from these patients showed impaired mitochondria-associated metabolism pathways. In situ hybridization and single-cell RNA sequencing revealed robust Cmpk2 expression in neurons and vascular endothelial cells (vECs), two cell types with high energy expenditure in the brain. The neurons in Cmpk2-knockout (KO) mice have fewer mitochondrial DNA copies, down-regulated mitochondrial proteins, reduced ATP production, and elevated intracellular inorganic phosphate (Pi) level, recapitulating the mitochondrial dysfunction observed in the PBMCs isolated from the FBC patients. Morphologically, the cristae architecture of the Cmpk2-KO murine neurons was also impaired. Notably, calcification developed in a progressive manner in the homozygous Cmpk2-KO mice thalamus region as well as in the Cmpk2-knock-in mice bearing the patient mutation, thus phenocopying the calcification pathology observed in the patients. Together, our study identifies biallelic variants of CMPK2 as novel genetic factors for FBC; and demonstrates how CMPK2 deficiency alters mitochondrial structures and functions, thereby highlighting the mitochondria dysregulation as a critical pathogenic mechanism underlying brain calcification.

[Status of personal information sharing on HIV between sexual partners among men who have sex with men who met casual sexual partners on the internet in Zhejiang province]

Objective: To identify the status and determinants of sharing personal HIV information with sexual partners among men who have sex with men (MSM) meeting their casual sexual partners on the internet. Methods: A cross-sectional study was conducted in five cities (Hangzhou, Ningbo, Wenzhou, Taizhou and Shaoxing) in Zhejiang province. The recruitment was enrolled by MSM social organization and in voluntary counseling and testing clinics, with a sample size of 793. A self-designed network questionnaire collected essential characteristics, HIV knowledge, sexual behavior, and sharing personal HIV status. SPSS 20.0 software was used for statistical analysis. Results: Among 767 MSM enrolled 302 MSM who reported finding casual sexual partners on the internet were enrolled in the analysis. MSM reported finding casual partners on the internet only, finding sexual partners online and in places were 62.6% (189/302) and 37.4% (113/302), respectively. Among those reporting web-based sexual behavior in the last six months, 54.6% (165/302) informed their partners of their HIV status, 49.2% (146/297) inquired about HIV status, and 42.9% (82/191) knew HIV status before sex intercourse, 75.8% (113/149) reported consistent condom use with HIV negative partners. The multivariable logistic regression analysis showed that related factors of inconsistent inquired HIV status of partners included 25-34 years old (aOR=2.17, 95%CI: 1.20-3.91), >2 partners on the internet in the last six months (aOR=2.13, 95%CI: 1.27-3.57), low-risk perception of HIV infection with online partners (aOR=1.96, 95%CI:1.14-3.35), numbers of HIV testing >1 times (aOR=0.38, 95%CI: 0.22-0.66). Conclusions: The willingness to know the HIV status of partners among MSM who met sexual partners on the internet was high but with a low rate of knowing their sex partner's HIV status in Zhejiang province. However, the successful implementation proportion was low. Therefore, it is necessary to pay attention to people who are elderly, with less conscience about the risk of the sex partners on the internet, have more sex partners, and have received few HIV tests. In addition, peer education was needed to promote related intervention programs.

Visible imaging system with changeable field of view on the HL-2A tokamak

A new visible imaging system characterizing a flexible optical design and delivering high resolution frames is established on the HL-2A tokamak. It features a modular configuration, consisting of a front-end imaging lens, a set of bilateral telecentric relay lenses, and a camera. To avoid the effects of plasma radiation (x and gamma-rays) and magnetic field variation on the camera, it should be away from the coils. Therefore, the length of the relay lenses determines the total size of the imaging system. The main feature of this imaging system is to realize the variation of field of view (FOV) by interchanging the front-end prime lenses or by using a zoom lens directly rather than designing the optical system afresh, which lowers the cost drastically. The primary purpose of varying FOV is to enrich the versatility of this system, i.e., focusing on a narrow FOV such as gas puff imaging or a wide FOV such as the plasma cross sections. During the HL-2A experiments, this visible imaging system is used to provide high quality pictures of the plasma-wall interaction, divertor detachment, pellet injections, and so on. The frames confirmed that a strong radiation close to the X point is correlated with the completely detached inner target.

GGC repeat expansion of RILPL1 is associated with oculopharyngodistal myopathy

OBJECTIVE

Oculopharyngodistal myopathy (OPDM) is an adult-onset neuromuscular disease characterized by progressive ptosis, dysarthria, ophthalmoplegia, and distal muscle weakness. Recent studies revealed GGC repeat expansions in 5'-UTR of LRP12, GIPC1, and NOTCH2NLC are associated with OPDM. Despite these advances, around 30% of OPDM patients remain genetically undiagnosed. Herein, we aim to investigate genetic basis for undiagnosed OPDM patients in two unrelated Chinese Han families.

METHODS

Parametric linkage analysis was performed. Long-read sequencing followed by repeat-primed polymerase chain reaction (RP-PCR) and amplicon length polymerase chain reaction (AL-PCR) were used to determine the genetic cause. Targeted methylation sequencing was implemented to detect epigenetic changes. The possible pathogenesis mechanism was investigated by qPCR, immunoblotting, RNA FISH, and immunofluorescence staining of muscle biopsy samples.

RESULTS

The disease locus was mapped to 12q24.3. Subsequently, GGC repeat expansion in the promoter region of RILPL1 was identified in six OPDM patients from two families, findings consistent with a founder effect, designated as OPDM type 4 (OPDM4). Targeted methylation sequencing revealed hypermethylation at RILPL1 locus in unaffected individuals with ultralong expansion. Analysis of muscle samples showed no significant differences in RILPL1 mRNA or RILPL1 protein levels between patients and controls. Public CAGE-seq data indicated that alternative TSSs exist upstream of the RefSeq-annotated RILPL1 TSS. Strand-specific RNAseq data revealed bidirectional transcription from the RILPL1 locus. Finally, FISH/IF indicated that both sense and antisense transcripts formed RNA foci and were co-localized with hnRNPA2B1 and p62 in the intranuclear inclusions of OPDM4 patients.

INTERPRETATION

Our findings implicate abnormal GGC repeat expansions in the promoter region of RILPL1 as a novel genetic cause for OPDM, and suggest a methylation mechanism and a potential RNA toxicity mechanism are involved in OPDM4 pathogenesis. This article is protected by copyright. All rights reserved.

[Study on the diagnostic value of transient elastography, APRI and FIB-4 for liver fibrosis in children with non-alcoholic fatty liver disease]

Objective: To evaluate the diagnostic value of transient elastography, aspartate aminotransferase-to-platelet ratio index (APRI), and fibrosis index based on 4 factors (FIB-4) for liver fibrosis in children with non-alcoholic fatty liver disease (NAFLD). Methods: A retrospective study was conducted on 100 cases of nonalcoholic fatty liver disease in Hunan Children's Hospital between August 2015 to October 2020 to collect liver tissue pathological and clinical data. The receiver operating characteristic curve (ROC curve) was used to analyze the diagnostic value of liver stiffness measurement (LSM), APRI and FIB-4 in the diagnosis of different stages of liver fibrosis caused by NAFLD in children. Results: The area under the ROC curve (AUC) value of LSM, APRI and FIB-4 for diagnosing liver fibrosis (S≥1) were 0.701 [95% confidence interval (CI): 0.579 ~ 0.822, P = 0.011], 0.606 (95%CI: 0.436 ~ 0.775, P = 0.182), and 0.568 (95%CI: 0.397 ~ 0.740, P = 0.387), respectively. The best cut-off values were 6.65 kPa, 21.20, and 0.18, respectively. The AUCs value of LSM, APRI, and FIB-4 for diagnosing significant liver fibrosis (S≥ 2) were 0.660 (95% CI: 0.552 ~ 0.768, P = 0.006), 0.578 (95% CI: 0.464 ~ 0.691, P = 0.182) and 0.541 (95% CI: 0.427 ~ 0.655, P = 0.482), respectively. The best cut-off values were 7.35kpa, 24.78 and 0.22, respectively. The AUCs value of LSM, APRI and FIB-4 for the diagnosis of advanced liver fibrosis (S≥ 3) were 0.639 (95% CI: 0.446 ~ 0.832, P = 0.134), 0.613 (95% CI: 0.447 ~ 0.779, P = 0.223) and 0.587 (95% CI: 0.411 ~ 0.764, P = 0.346), respectively. The best cut-off values were 8.55kpa, 26.66 and 0.27, respectively. Conclusion: The transient elastography technique has a better diagnostic value than APRI and FIB-4 for liver fibrosis in children with NAFLD.

Chinese patients with hereditary spastic paraplegias (HSPs): a protocol for a hospital-based cohort study

INTRODUCTION

Hereditary spastic paraplegias (HSPs) are uncommon but not rare neurodegenerative diseases. More than 100 pathogenic genes and loci related to spastic paraplegia symptoms have been reported. HSPs have the same core clinical features, including progressive spasticity in the lower limbs, though HSPs are heterogeneous (eg, clinical signs, MRI features, gene mutation). The age of onset varies greatly, from infant to adulthood. In addition, the slow and variable rates of disease progression in patients with HSP represent a substantial challenge for informative assessment of therapeutic efficacy. To address this, we are undertaking a prospective cohort study to investigate genetic-clinical characteristics, find surrogates for monitoring disease progress and identify clinical readouts for treatment.

METHODS AND ANALYSIS

In this case-control cohort study, we will enrol 200 patients with HSP and 200 healthy individuals in parallel. Participants will be continuously assessed for 3 years at 12-month intervals. Six aspects, including clinical signs, genetic spectrum, cognitive competence, MRI features, potential biochemical indicators and nerve electrophysiological factors, will be assessed in detail. This study will observe clinical manifestations and disease severity based on different molecular mechanisms, including oxidative stress, cholesterol metabolism and microtubule dynamics, all of which have been proposed as potential treatment targets or modalities. The analysis will also assess disease progression in different types of HSPs and cellular pathways with a longitudinal study using t tests and χ² tests.

ETHICS AND DISSEMINATION

The study was granted ethics committee approval by the first affiliated hospital of Fujian Medical University (MRCTA, ECFAH of FMU (2019)194) in 2019. Findings will be disseminated via presentations and peer-reviewed publications. Dissemination will target different audiences, including national stakeholders, researchers from different disciplines and the general public.

TRIAL REGISTRATION NUMBER

NCT04006418.

[Effect of lipopolysaccharide-stimulated exosomes from human dental pulp stem cells combined with stromal cell-derived factor-1 on dental pulp regeneration]

Objective: To investigate the effect of exosomes from mild-inflammation- stimulated human dental pulp stem cells (hDPSC) combined with stromal cell-derived factor-1 (SDF-1) on dental pulp regeneration in rats. Methods: Primary hDPSCs were isolated, cultured and then stimulated by using lipopolysaccharide (LPS). The exosomes from the hDPSCs with (L-EXO) or without (N-EXO) LPS were extracted by overspeed differential centrifugation and were identified by transmission electron microscopy and Western blotting. Forty SD rats, aged 6-8 weeks, were equally divided into S group (SDF-1 alone), L+S group (L-EXO combined with SDF-1), N+S group (N-EXO combined with SDF-1) and blank control group (no substance implanted into the root canal) by random number table method. Bilateral mandibular first molars were used as the experimental teeth to establish pulpless root canal models and different contents were implanted into the root canals according to the groups. All rats were over-anesthetized and sacrificed at the 30th day after content implantation. Bilateral mandibular tissues were taken for histological evaluation by means of HE, Masson and immunohistochemical stainings. Results: The HE staining showed new pulp-like tissue in the root canals of all three experimental groups. The amount of new tissues and the number of cells in the tissues were greatest in L+S group and least in S group. Masson staining showed that the mineralized tissue in L+S group was arranged longitudinally along the root canal wall and the collagen fibers were arranged in an orderly fashion, while those in N+S group showed an irregular and disordered distribution. Quantitative analysis of the area of neovascularization in each group showed that the density of vessels in the L+S group [(2.03±0.65)%] was significantly higher than that in the S group [(0.65±0.05)%] and the N+S group [(1.06±0.38)%] respectively (F=5.879, P<0.05). Immunohistochemical staining showed that the expression of CXC chemokine receptor 4 (CXCR4) was significantly lower in S and L+S groups than in N+S group, with a statistically significant difference (F=8.633, P<0.01). Conclusions: Exosomes secreted by hDPSCs combined with SDF-1 might increase the amount of new tissue in the root canal and the density of blood vessels in the tissue. L-EXO showed a stronger effect than N-EXO did. The combination of L-EXO with SDF-1 might result in more regular arrangement of mineralized tissue and collagen fibers in the regenerative tissues.

Advances in gene therapy for neurogenetic diseases: a brief review

Neurogenetic diseases are neurological conditions with a genetic cause (s). There are thousands of neurogenetic diseases, and most of them are incurable. The development of bioinformatics and elucidation of the mechanism of pathogenesis have allowed the development of gene therapy approaches, which show great potential in treating neurogenetic diseases. Viral vectors delivery, antisense oligonucleotides, gene editing, RNA interference, and burgeoning viroid delivery technique are promising gene therapy strategies, and commendable therapeutic effects in the treatment of neurogenetic diseases have been achieved (Fig. 1). This review highlights a sampling of advances in gene therapies for neurogenetic disorders. Fig. 1 Examples of gene therapy strategies used in the treatment of neurogenetic diseases. The schematic diagram shows different gene therapy approaches used for treating a sampling of neurogenetic disorders, such as ASO therapy, gene editing, gene augmentation, and RNA interference.

Mutation Analysis of MYORG in a Chinese Cohort With Primary Familial Brain Calcification

Primary familial brain calcification (PFBC) is a progressive neurological disorder manifesting as bilateral brain calcifications in CT scan with symptoms as parkinsonism, dystonia, ataxia, psychiatric symptoms, etc. Recently, pathogenic variants in MYORG have been linked to autosomal recessive PFBC. This study aims to elucidate the mutational and clinical spectrum of MYORG mutations in a large cohort of Chinese PFBC patients with possible autosomal recessive or absent family history. Mutational analyses of MYORG were performed by Sanger sequencing in a cohort of 245 PFBC patients including 21 subjects from 10 families compatible with a possibly autosomal-recessive trait and 224 apparently sporadic cases. In-depth phenotyping and neuroimaging features were investigated in all patients with novel MYORG variants. Two nonsense variants (c.442C > T, p. Q148*; c.972C > A, p. Y324*) and two missense variants (c.1969G>C, p. G657R; c.2033C > G, p. P678R) of MYORG were identified in four sporadic PFBC patients, respectively. These four novel variants were absent in gnomAD, and their amino acid were highly conserved, suggesting these variants have a pathogenic impact. Patients with MYORG variants tend to display a homogeneous clinical spectrum, showing extensive brain calcification and parkinsonism, dysarthria, ataxia, or vertigo. Our findings supported the pathogenic role of MYORG variants in PFBC and identified two pathogenic variants (c.442C > T, c.972C > A), one likely pathogenic variant (c.2033C > G), and one variant of uncertain significance (c.1969G>C), further expanding the genetic and phenotypic spectrum of PFBC-MYORG.

Exhausting T Cells During HIV Infection May Improve the Prognosis of Patients with COVID-19

T-cell reduction is an important characteristic of coronavirus disease 2019 (COVID-19), and its immunopathology is a subject of debate. It may be due to the direct effect of the virus on T-cell exhaustion or indirectly due to T cells redistributing to the lungs. HIV/AIDS naturally served as a T-cell exhaustion disease model for recognizing how the immune system works in the course of COVID-19. In this study, we collected the clinical charts, T-lymphocyte analysis, and chest CT of HIV patients with laboratory-confirmed COVID-19 infection who were admitted to Jin Yin-tan Hospital (Wuhan, China). The median age of the 21 patients was 47 years [interquartile range (IQR) = 40-50 years] and the median CD4 T-cell count was 183 cells/μl (IQR = 96-289 cells/μl). Eleven HIV patients were in the non-AIDS stage and 10 were in the AIDS stage. Nine patients received antiretroviral treatment (ART) and 12 patients did not receive any treatment. Compared to the reported mortality rate (nearly 4%-10%) and severity rate (up to 20%-40%) among COVID-19 patients in hospital, a benign duration with 0% severity and mortality rates was shown by 21 HIV/AIDS patients. The severity rates of COVID-19 were comparable between non-AIDS (median CD4 = 287 cells/μl) and AIDS (median CD4 = 97 cells/μl) patients, despite some of the AIDS patients having baseline lung injury stimulated by HIV: 7 patients (33%) were mild (five in the non-AIDS group and two in the AIDS group) and 14 patients (67%) were moderate (six in the non-AIDS group and eight in the AIDS group). More importantly, we found that a reduction in T-cell number positively correlates with the serum levels of interleukin 6 (IL-6) and C-reactive protein (CRP), which is contrary to the reported findings on the immune response of COVID-19 patients (lower CD4 T-cell counts with higher levels of IL-6 and CRP). In HIV/AIDS, a compromised immune system with lower CD4 T-cell counts might waive the clinical symptoms and inflammatory responses, which suggests lymphocyte redistribution as an immunopathology leading to lymphopenia in COVID-19.

Potential markers for sample size estimations in hereditary spastic paraplegia type 5

Background

Aim to identify potential biomarkers to assess therapeutic efficacy for hereditary spastic paraplegias type 5 (SPG5) by investigating the clinical, cerebrospinal fluid (CSF) and magnetic resonance imaging (MRI) features.

Methods

We performed a cross-sectional study to compare SPG5 patients with age- and sex-matched healthy controls who underwent conventional and quantitative MRI techniques of spinal cord (C1-T9) and brain. SPG5 patients also underwent assessment for clinical status and CSF biomarkers (27-hydroxycholesterol, neurofilament light). We identified a set of markers with standardized effect sizes (|t|> 0.5) to estimate sample sizes for disease progression (disease duration > 14 years vs. ≤ 14 years).

Results

Seventeen genetically confirmed SPG5 patients (11 men, 6 women; age range, 13–49 years; median disease duration, 14 years) were enrolled. Compared to healthy controls, the total spinal cord area (SCA) of SPG5 patients was reduced particularly at the thoracic levels (cervical levels: 12–27%; thoracic levels 41–60%). Patients did not show significant alterations of brain signal abnormalities or atrophy relative to controls. A total of 10 surrogate markers were selected and a minimum sample size was achieved with the measurement of SCA on T9 (n = 22) much less that what would be required if using clinical disability assessment (n = 124).

Conclusions

SPG5 patients showed distinct MRI features of spinal cord atrophy without significant brain alterations. Our finding supports the measurements of spinal cord on T9 level as potential endpoint for SPG5 clinical trials.

Trial registration ClinicalTrials.gov, NCT04006418. Registered 05 July 2019, https://clinicaltrials.gov/ct2/show/NCT04006418?term=NCT04006418&draw=2&rank=1.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-02014-w.

[Prediction of the vaulting after posterior chamber intraocular lens implantation]

Objective: To investigate the influencing factors on the vaulting one month after implantable collamer lens (ICL) implantation, and to develop and verify a prediction formula. Methods: The first half of this study was retrospective case series study, and the second half was cross-sectional stydy. A total of 83 eyes of 83 patients who underwent ICL implantation in the Lixiang Eye Hospital of Soochow University were included in the first half of the study, with an average age of (27±5) years, from August 1, 2019 to December 30, 2019. All patients underwent a complete preoperative examination, including axis length, anterior chamber depth, comprehensive optometry, intraocular pressure, central corneal thickness, white-to-white diameter, horizontal and vertical sulcus-to-sulcus diameter (STS), crystalline lens thickness (LT), corneal curvature, and bright and dark pupil diameter. Multiple linear regression (stepwise) was used to develop a prediction formula. In the validation part, a total of 65 people (65 eyes) were included, with an average age of (26±5) years, from March 1, 2020 to June 1, 2020. The accuracy and reliability of the formula were verified by the intergroup correlation coefficient and Bland-Altman consistency test. Results: At 1 month after surgery, ICL size had the greatest impact on the vaulting (β=0.942, P<0.001), followed by horizontal STS (β=-0.517, P<0.001), LT (β=-0.376, P<0.001), and vertical STS (β=-0.257, P=0.017). The influence of other factors was not statistically significant (all P>0.05). The regression equation was as follows: the vaulting (μm)=-1 369.05+657.12×ICL size-287.41×horizontal STS-432.50×LT-137.33×vertical STS (the fitting degree R=0.813, R²=0.660, and corrected R²=0.643). In the verification part, the predicted average vaulting was (497.31±102.75) μm, while the actual vaulting was (514.62±152.99) μm. About 96.92% (63/65) of the patients were fitted in the moderate vault, and 3.08% (2/65) were in the high vault. The intergroup correlation coefficient was 0.581. According to the Bland-Altman test, the actual vaulting was 17.31 μm, higher than the predicted value, and the 95% confidence interval of the difference was -260.28 to 294.90 μm. Conclusion: The ICL size, horizontal and vertical STS and LT are the factors that affect and predict the vaulting one month after ICL implantation, and our prediction formula has good accuracy and reliability. (Chin J Ophthalmol, 2021, 57: 519-525).

[Diagnosis and treatment of anastomotic leak after low anterior resection for rectal cancer: current status and future prospect]

Anastomotic leak is one of inevitable postoperative complications of rectal cancer. With the improvement of surgical techniques, the enhancement of the cognization of rectal cancer, and the development of surgical instruments, surgical procedures of rectal cancer are getting more sophisticated. The anastomosis is performed lower and lower, however the incidence of anastomotic leak is not significantly decreased. In addition, different from intraperitoneal anastomotic leak, the low rectal anastomotic leak after low anterior resection has many special issues in the diagnosis and treatment in clinic. The incidence of peritonitis caused by low anastomotic leak is low, the onset time is late, and symptoms of peritonitis are mild. So most low anastomotic leak is treated conservatively, second surgical repair or resection of anastomotic site is rarely performed, and proximal intestinal diversion is commonly performed. In the prevention of low anastomotic leak, some techniques and precautions during the perioperative period and identification of high risk factors might play important roles. Combined our clinical experiences, we introduced the diagnosis, treatment, prevention and research progression of low anastomotic leak after anterior resection of low rectal cancer, we hope it would be helpful.

[Willingness of post-exposure prophylaxis and possible related factors in men who have sex with men]

Objective: To analyze the willingness of post-exposure prophylaxis (PEP) to prevent HIV transmission and related factors in men who have sex with men (MSM). Methods: Cross sectional survey design was used in this study. After informed consent, MSM aged 18 years or above and having had homosexual anal or oral sex in the past 6 months were recruited through "i WeChat" official account between September and November, 2019. Results: Of 1 517 MSM were surveyed, the proportion of MSM who had ever heard of PEP were 72.5% (1 100/1 517) and 87.9%(1 333/1 517) of the MSM said they would like to use PEP if it is needed.Multivariate logistic regression analysis suggested that aged above 25 year (OR=1.807, 95%CI: 1.090-2.995), HIV test history (OR=1.953, 95%CI: 1.171-3.256) and being aware of PEP (OR=2.163, 95%CI: 1.468-3.186) were the positive factors for PEP use, but an aware of the HIV status of sexual partner was the negative factor for PEP (OR=0.602, 95%CI: 0.407-0.890). Among MSM who had ever heard of PEP, the positive factors for PEP use included living in Zhejiang (OR=1.942, 95%CI: 1.097-3.438), aged above 25 years (OR=2.431, 95%CI: 1.331-4.439), being aware of PEP (OR=3.714, 95%CI: 1.532-9.007) obtaining information about PEP service from MSM organization/volunteer/health organization. Conclusions: MSM's willingness to use PEP services was relatively high. Age, awareness of PEP related knowledge, and awareness of sexual partner's HIV infection status were the related factors. MSM organization/volunteer/health organization were the main forces for PEP promotion in MSM.

Investigate clinical characteristics and genetic mutations of CPVT patients in Taiwan and risk stratification

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ministry of Science and Technology

Background

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare and lethal arrhythmia in children and young adults. RYR2 mutation accounts for 60% of CPVT patients. While many articles about CPVT are published in the Caucasian population, only a few studies are based on Asian ethnicity. A CPVT scorecard proposed using Caucasian patients is proven effective in reducing the burden of variants of uncertain significance (VUS) of RYR2 mutations is not yet tested in the Asian population.

Purpose

Identify mutations among Taiwanese CPVT patients and compare genetic and clinical results with other ethnicities. We also tested the efficacy of the CPVT scorecard in Taiwanese CPVT patients.

Methods

40 clinically diagnosed CPVT patients and their family members were consecutively enrolled from multi-centers. We compared clinical characteristics and genetic results with other ethnicities, and applied the Caucasian CPVT scorecard to test whether it is applicable in Taiwanese CPVT patients.

Results

This is the first nationwide CPVT cohort in Taiwan. Among the 29 patients with CPVT-related gene mutation, 12 RYR2 variants was identified in our cohort with 5 of them unreported in previous studies. The RYR2 yield rate was 55%, similar to other ethnicities. Exercise-induced symptoms including syncope and cardiac arrest were more severe in Taiwanese CPVT cohort, compared to Japanese and Caucasian cohorts. The CPVT scorecard also successfully reduced the VUS rate for the Taiwanese cohort.

Conclusions

Our study demonstrated genetic difference in CPVT patients across ethnicities, suggesting the importance of genetic testing in Taiwan. The CPVT scorecard is applicable to Taiwanese CPVT patients and is a helpful tool in interpreting genetic test results in clinical practice. Clinical characteristics of the cohort Gender (male, %) 15 (52%) Mean age of onset (years) 18 ± 15 Exercise-related syncope or cardiac arrest (n, %) 23 (79%) Exercise-related cardiac arrest (n, %) 14 (48%) Family history of unexplained sudden cardiac death (n, %) 5 (17%) Heart rate (bpm) 73 ± 16 Exercise stress test or Holter positive (n, %) 14 (48%) Ventricular arrhythmia (n, %) 23 (79%) Beta-blockers only (n, %) 10 (35%) Intracardiac defibrillator implantation (n, %) 15 (52%) CPVT score 6 ± 3

Novel Compound Missense and Intronic Splicing Mutation in ALDH18A1 Causes Autosomal Recessive Spastic Paraplegia

Background: Hereditary spastic paraplegia (HSP) caused by mutations in ALDH18A1 have been reported as spastic paraplegia 9 (SPG9), with autosomal dominant and autosomal recessive transmission (SPG9A and SPG9B). SPG9 is rare and has shown phenotypic and genotypic heterogeneity in previous reports.

Methods: This study screened ALDH18A1 mutations in autosomal recessive HSP patients using combined whole exome sequencing and RNA splicing analysis. We conducted in silico investigations, co-segregation analysis, and ELISA-based analysis of P5CS (Δ1-pyrroline-5-carboxylate synthetase; encoded by ALDH18A1) concentration to validate the pathogenicity of the detected ALDH18A1 variants. All previously reported bi-allelic ALDH18A1 mutations and cases were reviewed to summarize the genetic and clinical features of ALDH18A1-related HSP.

Results: A novel missense mutation c.880T>C, p.S294P and an intronic splicing mutation c.-28-13A>G were both detected in ALDH18A1 in an autosomal recessive family presenting with a complicated form HSP. ELISA assays revealed significantly decreased P5CS concentration in the proband's plasma compared with that in the healthy controls. Moreover, review of previously reported recessive cases showed that SPG9B patients in our cohort presented with milder symptoms, i.e., later age at onset and without cognitive impairment.

Conclusion: The present study expands the genetic and clinical spectrum of SPG9B caused by ALDH18A1 mutation. Our work defines new genetic variants to facilitate future diagnoses, in addition to demonstrating the highly informative value of splicing mutation prediction in the characterization of disease-related intronic variants.

[Preliminary practice of multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases]

Objective: To preliminarily establish the multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases, and to explore its feasibility. Methods: In this prospective study a total of 150 children with hematological and oncological diseases visited immunization clinic of Shanghai Children's Medical Center from March 2017 to August 2018 were enrolled in this study. After establishing the multidisciplinary team, designing vaccination plan, staff training, implementation and quality control, a multidisciplinary immunization clinic was set up and the vaccination plan were implemented. The implementation rate of vaccination immunization, the HBsAb level and serum hepatitis B surface antibody (HBsAb) level before and after treatment, the HBsAb level and serum immunoglobulin G antibody (IgG) levels of measles, mumps, rubella (MMR) before and 6 months after immunization, the vaccine-related adverse reactions were assessed prospectively. Chi-square test or Fisher exact test was used to compare the differences of antibody level. Results: A total of 124 cases had been vaccinated as planned, with a coverage rate of 82.7%. Among these cases, the difference of HBsAb positive rate before and after treatment was significant (62.9% (78/124) vs.13.7% (17/124), χ²= 63.489, P<0.01). In 64 cases that completed three doses of hepatitis B immunization, there was a significant difference in HBsAb positive rate before and 6 months after immunization (6.3% (4/64) vs. 98.4% (63/64), P<0.01). In 40 cases that completed MMR immunization, the IgG antibody positive rate for measles (22.5% (9/40) vs. 82.5% (33/40), χ²=31.746,P<0.01), mumps (22.5% (9/40) vs.82.5% (33/40), χ²=28.872,P<0.01), rubella (25.0% (10/40) vs.62.5% (25/40), χ²=11.429, P<0.01) before and 6 months after immunization were significantly different. Of the 421 doses of immunization, 25 (5.9%) doses reported controlled systemic or local adverse event. Conclusions: The immunization of pediatric patients with hematological and oncological diseases is of great importance. The newly-developed multidisciplinary cooperation immunization model for Chinese children with hematological and oncological diseases is feasible, and the immunization protocol is safe and has a certain effect.

Higher Concentration of Plasma Glial Fibrillary Acidic Protein in Wilson Disease Patients with Neurological Manifestations

Background

Wilson disease is a rare, disabling, neurological genetic disease. Biomarkers of brain damage are less well developed.

Objective

The aim of this study was to evaluate the utility of plasma glial fibrillary acidic protein as a biomarker for neurological involvement in patients with Wilson disease.

Methods

This prospective cross‐observational study compared plasma glial fibrillary acidic protein concentration among different subtypes of patients with Wilson disease and healthy control subjects. Plasma glial fibrillary acidic protein levels were measured in 94 patients and 25 healthy control subjects. Patients were divided into two subtypes: patients with neurological manifestations (n = 74) or hepatic manifestations (n = 20).

Results

Median levels of plasma glial fibrillary acidic protein were significantly elevated in patients with neurological manifestations (143.87 pg/mL) compared with those with hepatic manifestations (107.50 pg/mL) and healthy control subjects (86.85 pg/mL). Receiver operating characteristic curve revealed that a plasma glial fibrillary acidic protein cutoff value of 128.8 pg/mL provides sufficient sensitivity (80.0%) and specificity (63.5%) to differentiate patients with neurological manifestations from those with hepatic manifestations.

Conclusions

Plasma glial fibrillary acidic protein may serve as a biomarker for distinguishing different subtypes of Wilson disease. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society

[Efficacy and safety of hepatitis B re-vaccination in children after completion of chemotherapy and(or) hematopoietic stem cell transplantation]

Objective: To assess the anti-hepatitis B surface antibody (HBsAb) titers in children after completion of chemotherapy and (or) hematopoietic stem cell transplantation (HSCT), evaluate the efficacy and safety of the current hepatitis B re-vaccination schedule. Methods: A total of 239 children who completed their chemotherapy and (or) HSCT and visited the vaccination clinic of Shanghai Children's Medical Center from March 2017 to July 2019 were enrolled in this study. According to the previous diseases, patients were divided into leukemia group (85 cases), lymphoma group (30 cases), solid tumor group (49 cases) and non-malignant hematological disease group (75 cases). According to the treatment of previous diseases, the patients were divided into chemotherapy group (126 cases), HSCT group (89 cases) and chemotherapy plus HSCT group (24 cases). HBsAb titers were assessed both at the time of diagnosis and after completion of treatment and some children who were HBsAb seronegative were re-vaccinated with 3 doses of hepatitis B vaccine, the vaccine-related adverse reactions were monitored. HBsAb titers were measured again one month after the completion of inoculation. HBsAb titers were defined as negative at levels <10 U/L and positive at ≥ 10 U/L. Chi-square test or Fisher exact test was used to compare the difference of negative conversion rate of hepatitis B antibody between groups, and Logistic regression was used to explore the risk factors of hepatitis B antibody negative conversion. Results: Among 239 patients, there were 143 males and 96 females. At the time of diagnosis, 179 patients (74.9%) were HBsAb seropositive and 60 patients (25.1%) were HBsAb seronegative. After completion of chemotherapy and (or) HSCT, 133 of 179 children with HBsAb seropositive (74.3%) at diagnosis became HBsAb seronegative. Univariate analysis showed significant differences at the negative conversion rates of HBsAb between different disease groups (χ²=10.211，P=0.015), different treatments groups (χ²=14.899，P<0.01) and different HBsAb titers groups before treatment (χ²=32.117，P<0.01). Logistic regression showed that HSCT (chemotherapy group as the reference, odds ratio (OR）=2.999, 95% confidence interval (CI) 1.276-7.050，P=0.012) and HBsAb titers<328.2 U/L before treatment (HBsAb titers≥328.2 U/L group as the reference, OR=6.397， 95% CI3.159-12.954，P<0.01) were risk factors for negative conversion of HBsAb. Among 48 patients whose HBsAb was seronegative after completion of chemotherapy and (or) HSCT and re-vaccinated with hepatitis B vaccine, 47 (97.9%) cases became HBsAb seropositivie. No serious adverse effects or complications were reported among these patients. Conclusions: After completion of chemotherapy and (or) HSCT, most children completely lose their protective humoral immunity against hepatitis B. Hepatitis B re-vaccination schedule can be efficiently and safely applied in those patients.

Median Nerve-Neurophysiological Index Correlates With the Survival of Patients With Amyotrophic Lateral Sclerosis

Objective: This study aims to explore the association between median nerve-neurophysiological index (NI) and survival of patients with amyotrophic lateral sclerosis (ALS).

Methods: A retrospective case series with a prospective follow-up study was performed in 238 patients with ALS. Their clinical profiles and NI were recorded. Kaplan-Meier curves and Cox regression were adopted to perform survival analysis.

Results: The median survival time of all ALS cases was 33.0 months. Multivariate analysis showed that older age of onset, shorter diagnostic delay, higher ΔALSFRS-R, and faster progression {NI ≤ 2.15; hazard ratio [HR] = 1.543 [95% confidence interval (CI), 1.136–2.094]} were associated with short survival. NI was correlated with ALSFRS-R at baseline (r_s = 0.3153; p < 0.0001) and ALSFRS-R at different time points of follow-up (r_s = 0.5127; p < 0.0001). The higher NI slope of decline (> 0.25) showed shorter survival compared with the lower group (≤ 0.25; 34.0 vs. 52.0 months; p = 0.0003). A predictive model was constructed based on the age of onset, diagnostic delay, median nerve NI, and ΔALSFRS-R. The higher predictive score (> 14) showed significantly shorter survival compared with the lower group (≤ 14; HR = 3.907, 95% CI, 2.857–5.342).

Conclusion: Median nerve NI and its slope of decline were predictive of survival of ALS.

Novel CAPN1 mutations extend the phenotypic heterogeneity in combined spastic paraplegia and ataxia

OBJECTIVE

Recessive mutations in the CAPN1 gene have recently been identified in spastic paraplegia 76 (SPG76), a complex hereditary spastic paraplegia (HSP) that is combined with cerebellar ataxia, resulting in an ataxia-spasticity disease spectrum. This study aims to assess the influence of CAPN1 variants on the occurrence of SPG76 and identify factors potentially contributing to phenotypic heterogeneity.

METHODS

We screened a cohort of 240 unrelated HSP families for variants in CAPN1 using high-throughput sequencing analysis. We described in detail the clinical and genetic features of the SPG76 patients in our cohort and summarized all reported cases.

RESULTS

Six unreported CAPN1-associated families containing eight patients with or without cerebellar ataxia were found in our cohort of HSP cases. These patients carried three previously reported homozygous truncating mutations (p.V64Gfs^* 103, c.759+1G>A, and p.R285^* ), and three additional novel compound heterozygous missense mutations (p.R481Q, p.P498L, and p.R618W). Lower limbs spasticity, hyperreflexia, and Babinski signs developed in about 94% of patients, with ataxia developing in 63% of cases. In total, 33 pathogenic mutations were distributed along the three reported functional domains of calpain-1 protein, encoded by CAPN1, with no hotspot region. A comparison of gender distribution between the two groups indicated that female SPG76 patients were significantly more likely to present with complicated HSP than male patients (P = 0.015).

INTERPRETATION

Our study supports the clinically heterogeneous inter- and intra-family variability of SPG76 patients, and demonstrates that gender and calpain-1 linker structure may contribute to clinical heterogeneity in SPG76 cases.

[The role of large-scale testing platform in the prevention and control of the COVID-19 pandemic: an empirical study based on a novel numerical model]

Objective: China adopted an unprecedented province-scale quarantine since January 23rd 2020, after the novel coronavirus (COVID-19) broke out in Wuhan in December 2019. Responding to the challenge of limited testing capacity, large-scale (>20 000 tests per day) standardized and fully-automated laboratory (Huo-Yan) was built as an ad-hoc measure. There is so far no empirical data or mathematical model to reveal the impact of the testing capacity improvement since quarantine. Methods: Based on the suspected case data released by the Health Commission of Hubei Province and the daily testing data of Huo-Yan Laboratory, the impact of detection capabilities on the realization of "clearing" and "clearing the day" of supected cases was simulated by establishing a novel non-linear and competitive compartments differential model. Results: Without the establishment of Huo-Yan, the suspected cases would increase by 47% to 33 700, the corresponding cost of quarantine would be doubled, the turning point of the increment of suspected cases and the achievement of "daily settlement" (all newly discovered suspected cases are diagnosed according to the nucleic acid testing result) would be delayed for a whole week and 11 days. If the Huo-Yan Laboratory could ran at its full capacity, the number of suspected cases could start to decrease at least a week earlier, the peak of suspected cases would be reduced by at least 44%, and the quarantine cost could be reduced by more than 72%. Ideally, if a daily testing capacity of 10 500 tests was achieved immediately after the Hubei lockdown, "daily settlement" for all suspected cases could be achieved. Conclusions: Large-scale, standardized clinical testing platform, with nucleic acid testing, high-throughput sequencing, and immunoprotein assessment capabilities, need to be implemented simultaneously in order to maximize the effect of quarantine and minimize the duration and cost of the quarantine. Such infrastructure, for both common times and emergencies, is of great significance for the early prevention and control of infectious diseases.

Quantitative assessment of postural instability in spinocerebellar ataxia type 3 patients

Objective

Spinocerebellar ataxia type 3 (SCA3) is one of the most common hereditary neurodegenerative diseases, with balance instability as main symptom. Balance quantification is crucial for evaluating the efficacy of therapeutic interventions. However, balance evaluation in SCA3 is often subject to bias. Here, we aimed to quantitatively evaluate postural instability and investigate the relationship between postural instability and clinical characteristics in SCA3 patients.

Methods

Sixty‐two SCA3 patients and 62 normal controls were recruited, and their postural balance was measured using a posturographic platform. Principal component analysis was performed as data reduction to identify postural instability factors. Multivariable linear regression was used to investigate potential risk factors for postural instability and to explore whether postural instability predicts the severity and progression of ataxia in SCA3 patients.

Results

We found SCA3 patients experience postural instability characterized by significant impairment in static and dynamic stability. The condition without visual feedback was the most sensitive measure in differentiating SCA3 from controls. Regression analyses revealed that ataxia severity predicted both static (P = 0.014) and dynamic stability (P = 0.001). Likewise, along with expanded CAG repeats (P < 0.001), both static (P < 0.001) and dynamic stability (P < 0.001) predicted ataxia severity, but not ataxia progression.

Interpretation

Our findings demonstrate the validity of using the Pro‐kin system for assessing postural instability in SCA3 patients. This type of quantitative assessment of balance dysfunction can contribute to clinical trials and balance rehabilitation in SCA3 patients.

Stop-gain mutations in UBAP1 cause pure autosomal-dominant spastic paraplegia

Hereditary spastic paraplegias refer to a heterogeneous group of neurodegenerative disorders resulting from degeneration of the corticospinal tract. Clinical characterization of patients with hereditary spastic paraplegias represents progressive spasticity, exaggerated reflexes and muscular weakness. Here, to expand on the increasingly broad pools of previously unknown hereditary spastic paraplegia causative genes and subtypes, we performed whole exome sequencing for six affected and two unaffected individuals from two unrelated Chinese families with an autosomal dominant hereditary spastic paraplegia and lacking mutations in known hereditary spastic paraplegia implicated genes. The exome sequencing revealed two stop-gain mutations, c.247_248insGTGAATTC (p.I83Sfs*11) and c.526G>T (p.E176*), in the ubiquitin-associated protein 1 (UBAP1) gene, which co-segregated with the spastic paraplegia. We also identified two UBAP1 frameshift mutations, c.324_325delCA (p.H108Qfs*10) and c.425_426delAG (p.K143Sfs*15), in two unrelated families from an additional 38 Chinese pedigrees with autosomal dominant hereditary spastic paraplegias and lacking mutations in known causative genes. The primary disease presentation was a pure lower limb predominant spastic paraplegia. In vivo downregulation of Ubap1 in zebrafish causes abnormal organismal morphology, inhibited motor neuron outgrowth, decreased mobility, and shorter lifespan. UBAP1 is incorporated into endosomal sorting complexes required for transport complex I and binds ubiquitin to function in endosome sorting. Patient-derived truncated form(s) of UBAP1 cause aberrant endosome clustering, pronounced endosome enlargement, and cytoplasmic accumulation of ubiquitinated proteins in HeLa cells and wild-type mouse cortical neuron cultures. Biochemical and immunocytochemical experiments in cultured cortical neurons derived from transgenic Ubap1flox mice confirmed that disruption of UBAP1 leads to dysregulation of both early endosome processing and ubiquitinated protein sorting. Strikingly, deletion of Ubap1 promotes neurodegeneration, potentially mediated by apoptosis. Our study provides genetic and biochemical evidence that mutations in UBAP1 can cause pure autosomal dominant spastic paraplegia.

Ethnicity and health inequalities: an empirical study based on the 2010 China survey of social change (CSSC) in Western China

BACKGROUND

In China, ethnic minorities often live in frontier areas and have a relatively small population size, and tremendous social transitions have enlarged the gap between eastern and western China, with western China being home to 44 ethnic minority groups. These three disadvantages have health impacts. Examining ethnicity and health inequality in the context of western China is therefore essential.

METHODS

This paper is based on data from the 2010 China Survey of Social Change (CSSC2010), which was conducted in 12 provinces, autonomous regions and province-level municipalities in western China and had a sample size of 10,819. We examined self-rated health and disparities in self-rated health between ethnic minorities and Han Chinese in the context of western China. Self-rated health was coded as poor or good, and ethnicity was coded as ethnic minority or Han Chinese. Ethnic differences in self-rated health was examined by using binary logistic regression. Associations among sociodemographic variables, SES variable, health behaviour variable, health problem variables and self-rated health were also explored.

RESULTS

Fourteen percent of respondents reported their health to be poor. A total of 15.75% of ethnic minorities and 13.43% of Han Chinese respondents reported their health to be poor, indicating a difference in self-rated health between ethnic minorities and Han Chinese. Age, gender, marital status, education, alcohol, and health problems were the main factors that affected differences in self-rated health.

CONCLUSION

In western China, there were obvious ethnic disparities in self-rated health. Elderly ethnic minorities, non-partnered ethnic minorities, ethnic minorities with an educational level lower than middle school, and ethnic minorities with chronic disease had higher odds of poor self-rated health.

Fast charge exchange recombination spectroscopy on HuanLiu-2A tokamak

A Fast Charge eXchange Recombination Spectroscopy (CXRS) diagnostic with eight radial channels has been implemented on a HuanLiu-2A (HL-2A) tokamak with a time resolution of up to 10 kHz monitoring helium II spectra or 1 kHz monitoring carbon VI spectra. The crucial aspects of the fast CXRS are to improve the spectral intensity and the acquisition frequency. The spectral intensity has been greatly enhanced by customized fiber bundles. The main boost in optimizing the acquisition frequency is achieved by binning more pixel rows of the charge coupled device (CCD) representing one radial channel and by reducing the effective image area of the CCD. Consequently, the sawtooth oscillations of ion temperature and rotation velocity are continuously observed for the first time in the HL-2A tokamak.

Ataxic Severity Is Positively Correlated With Fatigue in Spinocerebellar Ataxia Type 3 Patients

Background: Spinocerebellar ataxia type 3 (SCA3) is an inherited form of ataxia that leads to progressive neurodegeneration. Fatigue is a common non-motor symptom in SCA3 and other neurodegenerative diseases, such as Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS). Although risk factors to fatigue in these diseases have been thoroughly studied, whether or not fatigue can affect clinical phenotypes has yet to be investigated. Methods: Ninety-one molecularly confirmed SCA3 patients and 85 age- and sex-matched controls were recruited for this study. The level of fatigue was measured using the 14-item Fatigue Scale (FS-14), and the risk factors to fatigue and how fatigue correlates with clinical phenotypes were studied using multivariable linear regression models. Results: We found that the severity was significantly higher in the SCA3 group than in the control group (9.30 ± 3.04% vs. 3.94 ± 2.66, P = 0.000). Daytime somnolence (β = 0.209, P = 0.002), severity of ataxia (β = 0.081, P = 0.006), and poor sleep quality (β = 0.187, P = 0.037) were found to have a positive relationship with fatigue. Although fatigue had no relationship with age at onset or ataxic progression, we found that it did have a positive relationship with the severity of ataxia (β = 7.009, P = 0.014). Conclusions: The high level of fatigue and the impact of fatigue on the clinical manifestation of SCA3 patients suggest that fatigue plays a large role in the pathogenesis of SCA3, thus demonstrating the need for intervention and treatment options in this patient cohort.

[Evaluation on the confidence of refusing unprotected sex behavior and related factors among college students in Zhejiang province]

Objective: To understand the confidence-related factors of refusing unprotected sex behavior among college students in Zhejiang province. Methods: Stratified cluster random sampling method was conducted among college students from 13 colleges and universities in Zhejiang province, from October to November, 2018. A total of 3 718 students who self-reported "ever having had sexual contacts" were enrolled. Chi-square test was used to compare the confidence of rejecting unprotected sex under different demographic characteristics, sexual attitude/behaviors and different intervention approaches. Multivariate logistic regression model was used to analyze the related factors. Results: A total of 3 718 college students were involved in this study with average age as (20.17±1.38) years old and 70.5% (2 620/3 718) were male. The proportions of having confidence to refuse unprotected sex behavior were 74.9% (1 963/2 620) of male and 77.9% (896/1 098) of female students, respectively. According to the results from multivariate logistic regression analysis, factors that related to the confidence of refusing unprotected sex behavior in male students would include, did not accept casual sex behavior (compared with accepted students, OR=2.247, 95%CI: 1.828-2.762), did not accept homosexual behavior (compared with accepted students, OR=1.810, 95%CI: 1.302- 2.516), having casual sex behavior in the past one year (compared with having no sex behavior, OR=1.345, 95%CI: 1.051-1.721), aware of the availability of HIV self-test reagents service in college (compared with did not knew, OR=1.381, 95%CI: 1.011-1.887), having taken the HIV infection risk self-assessment in college (compared with did not take, OR=1.707, 95%CI: 1.374-2.121). In female students, the factors would include: being urban resident (compared with rural residence, OR=1.816, 95%CI: 1.225-2.693), 21 years old or above (compared with 20 years old or below, OR=1.469, 95%CI: 1.075-2.007), having taken the HIV infection risk self-assessment in college (compared with did not take, OR=1.597, 95%CI: 1.093-2.333), etc. Conclusions: Both male and female college students had higher confidence in refusing unprotected sex behavior. For male students, refusing casual or homosexual contacts, having casual sex in the recent year, knowing HIV self-test reagents service and having had HIV-related risk self-assessment in college as related factors. However, for female students; city residence, 21 years old and above, and having a HIV infection risk self- assessment in college appeared as related factors. Sexual health education should be strengthened to reduce unprotective sex behavior and to promote HIV infection risk self-assessment among the college students.