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Objective:To examine whether the regional methylation levels at the most distal D4Z4 repeat units (RU) in the 4qA-permissive haplotype were associated with disease severity and progression in facioscapulohumeral muscular dystrophy type 1 (FSHD1).Methods:This was a 21-year, retrospective, and observational cohort study conducted at the Fujian Neuromedical Centre (FNMC) in China. Methylation levels of the most distal D4Z4 RU, including 10 CpGs, were assessed in all participants by bisulfite sequencing. FSHD1 patients were stratified into 4 groups based on methylation percentage quartiles, including LM1 (low methylation), LM2 (low to intermediate methylation), LM3 (intermediate to high methylation), and highest methylation levels (HM). Patients received evaluations of motor function focusing on lower extremity (LE) progression at baseline and in follow-ups. FSHD clinical score (CS), age-corrected clinical severity scale (ACSS), and modified Rankin Scale were used to assess motor function.Results:The methylation levels of the 10 CpGs were significantly lower in all 823 genetically confirmed FSHD1 patients than in 341 healthy controls (HCs). CpG6 methylation levels could distinguish: 1) FSHD1 patients from HCs; 2) symptomatic from asymptomatic/unaffected patients; 3) patients with LE involvement from those without LE involvement, with AUCs (95% CI) of 0.9684 (0.9584–0.9785), 0.7417 (0.6903–0.7931), and 0.6386 (0.5816–0.6956), respectively. CpG6 methylation levels were negatively correlated with both CS (r = -0.392) and ACSS (r = -0.432), and positively correlated with onset age of first-ever muscle weakness (r = 0.297). For the LM1, LM2, LM3, and HM groups, the respective proportions of LE involvement were 52.9%, 44.2%, 36.9%, and 23.4%; and onset ages of LE involvement were 20, 26.5, 25, and 26.5 years. Cox regression analysis—adjusted for sex, age at examination, D4Z4 RU, and 4qA/B haplotype—showed that the LM1, LM2, and LM3 groups (i.e., groups with lower methylation levels) had a higher risk for independent ambulation loss, with HRs (95% CI) of 3.523 (1.565–7.930), 3.356 (1.458–7.727), and 2.956 (1.245–7.020), respectively.Conclusion:4q35 distal D4Z4 hypomethylation is correlated with disease severity and progression to lower extremity involvement.

Background: Facioscapulohumeral muscular dystrophy type 1 (FSHD1) is a rare, hereditary, and progressive muscular dystrophy characterized by weakness and wasting of the facial (facio-) and shoulder-upper arm (scapulo-humeral-) muscles. The clinical severity varies from nonpenetrant/asymptomatic to disability with independent ambulation loss or even wheelchair dependence. Expansion of our knowledge of the genetic model D4Z4 macrosatellite repeat contraction leading to inappropriate expression of DUX4 has led to advances in developing targeted therapeutic strategies. Thus, clinical trial readiness is now required, particularly patient registry. However, there is no FSHD registry in China, let alone any database of the epidemiology, natural history, and clinical management of FSHD. This nationwide, longitudinal, non-interventional, rare-disease patient registry (The China FSHD1 Registry, CF1R ) was established to address the paucity of data in FSHD1 and to help inform future clinical practice and optimization clinical management. Results: This explorative study aims to recruit all patients with a genetically confirmed diagnosis of FSHD1 in China. Practice data, including demographic factors, disease progression history, family history, and clinical and genetic features are collected; the protocol does not mandate any interventions. Patients will be continuously assessed for 10 years at 5-year intervals. Several data analyses and peer-reviewed publications are expected to be generated throughout this period. Conclusions: The data collected within this rare-disease patient registry (CF1R) will be utilized to synthesize real-world data on epidemiological information, disease progression, and clinical and (epi)genetic information, which are vital for adequate symptom management and clinical trial-readiness of FSHD1 in China. Ethics and dissemination The study was granted ethics committee approval by the First Affiliated Hospital of Fujian Medical University (MRCTA, ECFAH of FMU [2020]026) in 2020. 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 NCT04369209

PurposeTo analyse the clinical spectrum, genetic features, specific D4Z4 hypomethylation status and genotype–phenotype correlations for somatic mosaicism in facioscapulohumeral dystrophy (FSHD).MethodsThis was a prospective, hospital-based, case–control, observational study of 35 participants with FSHD with somatic mosaicism recruited over 10 years, with 17 penetrant patients and 18 non-penetrant mutation carriers. This study also included a univariate comparison of 17 paired mosaic and non-mosaic patients with FSHD.ResultsMosaic participants with FSHD varied in age of diagnosis (median 45; range 15–65 years), muscle strength (FSHD clinical score median 0; range 0–10 points), clinical severity (age-corrected clinical severity score (ACSS) median 0; range 0–467 points), D4Z4 repeats (median 3; range 2–5 units), mosaic proportion (median 55%; range 27%–72%) and D4Z4 methylation extent (median 49.82%; range 27.17%–64.51%). The genotypic severity scale and D4Z4 methylation extent were significantly associated with ACSS (p1=0.003; p2=0.002). Among the matched pairs, the 17 mosaic patients had shorter D4Z4 repeats, lower FSHD clinical scores and lower ACSS than non-mosaic patients. Additionally, 34 of 35 (97%) participants carried two mosaic arrays, while a single patient had three mosaic arrays (3%). Two cases also carried four-type non-mosaic arrays on chromosome 10 (translocation configuration).ConclusionsBroadly, this large mosaic FSHD cohort exhibited significant clinical heterogeneity and relatively slight disease severity. Both genotypic severity scale and D4Z4 hypomethylation status served as modifiers of clinical phenotypes. Consistent with previous reports, mitotic interchromosomal/intrachromosomal gene conversion without crossover was here identified as a major genetic mechanism underlying mosaic FSHD.

Limb girdle muscular dystrophy LGMD R7 telethonin-related is a rare autosomal recessive muscle disorder characterized by proximal muscle weakness of pelvic and shoulder girdles. Mutation in TCAP is responsible for LGMD R7, and the disease has a wide geographic distribution in diverse populations, but genotype-phenotype relationships remain unclear. We collected 5 LGMD R7 patients from three unrelated Chinese families. The average onset age was 16 ± 1.41; the initial symptoms included progressive proximal muscle weakness in limbs, difficulty in fast running, and asymmetric muscle atrophy in calves. Muscle MR imaging showed varying severity of fatty infiltration in the pelvic girdle, thigh, and calf muscles, and the severity of muscle infiltration was related to the length of the disease course. Muscle histopathology revealed aberrantly sized muscle fibers, internal nuclei, split fibers, rimmed vacuoles, monocyte invasion, and necrotic fibers. Sequencing identified one novel and one previously reported TCAP mutation. Our study extends the known distribution of this rare muscular dystrophy and presents the first detailed clinical and genetic characterizations of LGMD R7 cases from the Chinese population. Our work expands the mutation spectrum known for LGMD R7 and emphasizes the need for clinicians to consider TCAP mutations when evaluating patients with symptoms of limb girdle muscular dystrophy.

Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common muscular dystrophy. FSHD type 1 (FSHD1) is caused by multicopy contraction of D4Z4 repeats on chromosome 4q35. Human induced pluripotent stem cell (hiPSC) lines serve as important research models for various types of diseases in vitro. Here, we reprogrammed human peripheral blood mononuclear cells (PMBCs) into hiPSCs with episomal plasmid from two FSHD1 patients. These hiPSC lines maintained normal karyotype and exhibited typical morphology. Both of them could express pluripotency markers and differentiate into three layers. The hiPSC lines could be used for screening potential therapeutic targets and mechanism research.

Summary: Background: Facioscapulohumeral muscular dystrophy type 1 (FSHD1) is a rare disease, which is often underdiagnosed due to its heterogeneous presentations and complex molecular genetic basis, leading to a lack of population-based epidemiology data, especially of prevalence and disease progression. Methods: Fujian Neuromedical Centre (FNMC) is a diagnosis centre for clinical-genetic FSHD in China, and the only one employing pulsed-field gel electrophoresis (PFGE)-based Southern blotting for all FSHD1 genetic tests. Three sources distributed across all six spatial zones in China, were used to obtain information regarding FSHD1 events, namely, FNMC, Genetic and Myopathy Group (branches of the Neurology Society of the Chinese Medical Association), and “FSHD-China” (an organization supported by FSHD patients). During 2001-2020, all genetically-confirmed FSHD1 from China were registered in FNMC. Follow-up was conducted in the 20-year period to obtain data on disease progression, which was mainly described in terms of independent ambulation loss. Findings: Of the 1,744 FSHD1 genetic tests (total test number 1,802) included in the analysis, 997 (57.2%) patients from 620 families were diagnosed with FSHD1. The estimated prevalence of genetically-confirmed FSHD1 in China is 0.75 per million (95% confidence interval [CI], 0.70-0.79) during 2001-2020, with 0.78 (95% CI, 0.72-0.85) in males and 0.71 (95% CI, 0.65-0.78) in females. The estimated prevalence increased from 0.22 (95% CI, 0.19-0.26) per million in 2001-2015 to 0.53 (95% CI, 0.49-0.57) per million in 2016-2020 (p < 0.001). The prevalence in Fujian province was 7.10 per million, 4.66 per million, and 2.44 per million, during 2001-2020, 2001-2015, and 2016-2020, respectively. Among the 861 symptomatic plus asymptomatic patients of the total 997 patients, the median onset age at first-ever muscle weakness was 16 years of age (range 1-81); the median number of contracted D4Z4 repeats was 5 units (range 1-9); the median 4qA-allele-specific methylation level was 41% (range 14%-69%). Of the 977 symptomatic patients followed-up during 2001-2020, 117 patients (12.0%) lost independent ambulation. The expected duration from onset of first-ever muscle weakness to onset of independent ambulation loss was 40 years. The group with loss of independent ambulation had a smaller number of contracted D4Z4 repeats (p < 0.001) and had an earlier onset age of first-ever muscle weakness (p < 0.001) compared to the group without loss of independent ambulation. Interpretation: Our research captures the largest genetically-confirmed FSHD1 population worldwide, to calculate its prevalence of 0.75 per million in China from 2001 to 2020. Approximately 12.0% of symptomatic plus asymptomatic patients of FSHD1 will lose independent ambulation in 40 years from onset of first-ever muscle weakness. Funding: This work has been supported by the grants (U2005201, 81870902, N.W.) and (81974193, 81671237, Z.Q.W.) from the National Natural Science Foundation of China; Joint Funds for the Innovation of Science and Technology of Fujian Province (2018Y9082) (N.W.), and the Key Clinical Specialty Discipline Construction Program of Fujian (N.W.).

Bal9 fault block is a medium-high temperature (58°C) reservoir in Baolige Oilfield. The crude oil is characterized by poor physical properties which has high wax and high gum content. The oil-water viscosity ratio is high and this leads to a low water flooding efficiency. The reservoir heterogeneity is high and the contradictions between layers are prominent. According to the characteristics of the oilfield, a microbial-gel combined flooding technology with the microbial flooding as the main body and the gel flooding as the auxiliary is developed to improve the overall development effect of the oilfield water flooding. Microorganism can improve the physical properties of crude oil, and appropriate gel flooding should be carried out to enlarge the sweep volume of microorganism work and improve the effect of microbial-gel combined flooding. By continuous application of this technology in Baolige Oilfield, the concentration of microorganisms is maintained at about 106 a/ml, and the whole microbial field is formed. The average annual reduction rate of crude oil is 48.1%. The microbial-gel combined flooding technology is verified to increase the recovery factor by 9.5%. Since the combined flooding was carried out in 2010, the recoverable reserves of the Ba19 block increased by 630,600 tons.

Intermediate Charcot-Marie-Tooth (CMT) disease is a heterogeneous group of inherited neuropathies characterized by progressive muscle weakness and atrophy of the distal extremities, distal sensory loss. There were still a large proportion of causative genes for intermediate CMT failed to be identified. Here, using whole-exome sequencing technique, we identified two novel missense mutations in ATP1A1 gene, c.620C>T (p.S207F) and c.2629G>A (p.G877S), in two Chinese CMT families. Further functional analysis revealed that these mutations led to the loss function of the ATP1A1 protein. The two mutations did not affect the levels of messenger RNA but possessed a damaging effect on ATP1A1 protein expression and they downregulated the protein levels of ATP1A1 by promoting its proteasome degradation. Taken together, we confirmed ATP1A1 as a novel causative gene for intermediate CMT.

This paper, as the sequel to previous work, develops numerical schemes for fractional diffusion equations on a two-dimensional finite domain with triangular meshes. We adopt the nodal discontinuous Galerkin methods for the full spatial discretization by the use of high-order nodal basis, employing multivariate Lagrange polynomials defined on the triangles. Stability analysis and error estimates are provided, which shows that if polynomials of degree $N$ are used, the methods are (N+1)-th order accurate for general triangulations. Finally, the performed numerical experiments confirm the optimal order of convergence., 26 pages, 5 figures