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The huge heterogeneity of the disease progression rate may cause inconsistent findings between local activity and functional connectivity of the primary sensorimotor area (PSMA) in amyotrophic lateral sclerosis (ALS). For illustration of this hypothesis, resting-state fMRI (RS-fMRI) data were collected and analyzed on 38 "definite" or "probable" ALS patients (19 fast and 19 slow, cut off median = 0.41) and 37 matched healthy controls. Amplitude of low frequency fluctuations (ALFFs) and functional connectivity strength (FCS) were analyzed within the PSMA. There was a decreased ALFF (p

Background and PurposeTwo clinical trials assessing the steroid-sparing effect of methotrexate (MTX) yielded conflicting results. Our objective was to investigate whether MTX would show a steroid-sparing effect in the treatment of generalized myasthenia gravis (MG) patients who fitted Myasthenia Gravis Foundation of America (MGFA) Class II and Class III.MethodsWe performed an 18-month prospective, randomized, open-labeled trial of prednisone combined with MTX 10 mg orally every week versus prednisone alone in 40 recently diagnosed MG patients of MGFA Class II and Class III between July 2014 and July 2018. The primary endpoint was the prednisone area under the dose–time curve (AUDTC) from months 3 to 18. Secondary endpoints included changes of the Quantitative Myasthenia Gravis Score (QMG), the Myasthenia Gravis Activity of Daily Living Score (MG-ADL), initial time of prednisone reduction, the median prednisone daily dose in each month, adverse events, and treatment failures in each group.ResultsForty participants were included; among those, 5 individuals withdrew. A total of 35 participants completed 18 months of follow-up (18 in prednisone+MTX, 17 in prednisone group). Combined use of MTX reduced the month 3–18 prednisone AUDTC (prednisone+MTX 5,663.44 ± 1,678.08 mg, prednisone 6,683.94 ± 678.08 mg, p = 0.03, 95% confidence interval -1916.01 to -124.98). The initial times of prednisone reduction were 4.34 ± 1.44 months in the prednisone+MTX group and 5.56 ± 2.05 months in the prednisone group (p = 0.04, 95% CI -2.41 to -0.03). The median daily prednisone dose was significantly lower in the prednisone+MTX group at month 6 and months 9–18. No significant differences were found in QMG and MG-ADL scores between the two groups. No serious drug-related adverse events were observed in both groups.ConclusionsThis study provides evidence that MTX has the steroid-sparing ability in generalized MG patients of MGFA Class II and Class III.Clinical Trial Registrationhttp://www.chictr.org.cn/showproj.aspx?proj=10563 identifier ChiCTR-IPR-15006081.

Background: Intravenous immunoglobulin (IVIG) has been commonly used to treat myasthenia gravis exacerbation, but is still ineffective in nearly 30% of patients. A variable number of tandem repeat (VNTR) polymorphism in the FCGRT gene has been found to reduce the efficiency of IgG biologics. However, whether the polymorphism influences the efficacy of IVIG in generalized myasthenia gravis (MG) patients with exacerbations remains unknown. Methods: The distribution of VNTR genotypes was analyzed in 334 patients with MG. Varied VNTR alleles were determined by capillary electrophoresis and confirmed by Sanger sequencing. Information of endogenous IgG levels were collected in patients without previous immunotherapy ( n = 26). Medical records of patients who received IVIG therapy were retrospectively analyzed for therapeutic outcomes of IVIG treatment ( n = 61). Patients whose Activities of Daily Living scores decreased by 2 or more points on day 14 were considered responders to the treatment. Results: The VNTR3/3 and VNTR2/3 genotypes were detected in 96.7% (323/334) and 3.4% (11/334) patients, respectively. Patients with VNTR2/3 heterozygosity had lower endogenous IgG levels than those with VNTR3/3 homozygosity (9.81 ± 2.61 g/L versus 12.41 ± 2.45g/L, p = 0.016). The response rate of IVIG therapy was 78.7% (48/61). All responders and nine non-responders were VNTR3/3 homozygotes, whereas all the patients with VNTR2/3 genotypes were non-responders ( n = 4). In patients who took IVIG treatments, endogenous IgG levels were significantly lower in non-responders compared with responders (12.93 ± 2.24 g/L versus 8.85 ± 2.69 g/L, p = 0.006), especially in VNTR2/3 heterozygotes (7.86 ± 1.78 g/L, p = 0.001). Conclusion: The VNTR2/3 genotype could influence endogenous IgG levels and serve as a predictive marker for poor responses to IVIG in MG patients.

Supplemental material, sj-pdf-1-tan-10.1177_1756286420986747 for VNTR2/VNTR3 genotype in the FCGRT gene is associated with reduced effectiveness of intravenous immunoglobulin in patients with myasthenia gravis by Shengyao Su, Qing Liu, Xueping Zhang, Xinmei Wen, Lin Lei, Faxiu Shen, Zhirong Fan, Jianying Duo, Yan Lu, Li Di, Min Wang, Hai Chen, Wenjia Zhu, Min Xu, Suobin Wang and Yuwei Da in Therapeutic Advances in Neurological Disorders

The study aims to identify clinical factors affecting tacrolimus blood trough concentration (C0) in myasthenia gravis (MG) patients and to optimize the initial dose of tacrolimus in MG treatment. A total of 103 MG patients participated in this study, and their clinical factors, medication regimens, C0 values and CYP3A5*3 polymorphisms were collected in detail. We used a linear mixed model to analyze the effect of multiple factors on the dosage-weighted C0 (C0:D) and performed subgroup analyses to investigate the consistency of correlations between influencing factors and the C0:D ratios. Among all factors, CYP3A5*3 polymorphism and age showed a strong positive correlation with C0:D ratios. The C0:D ratios (ng/ml·mg−1) were higher for CYP3A5*3/*3 than for CYP3A5*1 (mean difference: 1.038, 95% confidence interval [CI]: 0.820–1.256, P-value

As severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), the virus that causes COVID‐19, is highly infectious and variable, and given that we now understand a large proportion of asymptomatic carriers can be still infectious [1], it is expected that a normalization of epidemic prevention and control measures will be required for a long time worldwide. Our neurology department at Xuanwu Hospital in Beijing is one of the national centers for the research and treatment of neurological disorders in China.

Background: Intravenous immunoglobulin (IVIG) has been commonly used to treat myasthenia gravis exacerbation, but is still ineffective in nearly 30% of patients. A variable number of tandem repeat (VNTR) polymorphism in the FCGRT gene has been found to reduce the efficiency of IgG biologics. However, whether the polymorphism influences the efficacy of IVIG in generalized myasthenia gravis (MG) patients with exacerbations remains unknown. Methods: The distribution of VNTR genotypes was analyzed in 334 patients with MG. Varied VNTR alleles were determined by capillary electrophoresis and confirmed by Sanger sequencing. Information of endogenous IgG levels were collected in patients without previous immunotherapy (n = 26). Medical records of patients who received IVIG therapy were retrospectively analyzed for therapeutic outcomes of IVIG treatment (n = 61). Patients whose Activities of Daily Living scores decreased by 2 or more points on day 14 were considered responders to the treatment. Results: The VNTR3/3 and VNTR2/3 genotypes were detected in 96.7% (323/334) and 3.4% (11/334) patients, respectively. Patients with VNTR2/3 heterozygosity had lower endogenous IgG levels than those with VNTR3/3 homozygosity (9.81 ± 2.61 g/L versus 12.41 ± 2.45g/L, p = 0.016). The response rate of IVIG therapy was 78.7% (48/61). All responders and nine non-responders were VNTR3/3 homozygotes, whereas all the patients with VNTR2/3 genotypes were non-responders (n = 4). In patients who took IVIG treatments, endogenous IgG levels were significantly lower in non-responders compared with responders (12.93 ± 2.24 g/L versus 8.85 ± 2.69 g/L, p = 0.006), especially in VNTR2/3 heterozygotes (7.86 ± 1.78 g/L, p = 0.001). Conclusion: The VNTR2/3 genotype could influence endogenous IgG levels and serve as a predictive marker for poor responses to IVIG in MG patients.

The most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) is an intronic hexanucleotide repeat expansion in the C9orf72 gene. In disease, RNA transcripts containing this expanded region undergo repeat‐associated non‐AUG translation to produce dipeptide repeat proteins (DPRs), which are detected in brain and spinal cord of patients and are neurotoxic both in vitro and in vivo paradigms. We reveal here a novel pathogenic mechanism for the most abundantly detected DPR in ALS/FTD autopsy tissues, poly‐glycine‐alanine (GA). Previously, we showed motor dysfunction in a GA mouse model without loss of motor neurons. Here, we demonstrate that mobile GA aggregates are present within neurites, evoke a reduction in synaptic vesicle‐associated protein 2 (SV2), and alter Ca2+ influx and synaptic vesicle release. These phenotypes could be corrected by restoring SV2 levels. In GA mice, loss of SV2 was observed without reduction of motor neuron number. Notably, reduction in SV2 was seen in cortical and motor neurons derived from patient induced pluripotent stem cell lines, suggesting synaptic alterations also occur in patients., Poly‐glycine‐alanine (GA) aggregates present in neurons cause a reduction in synaptic release and loss of the synaptic vesicle protein SV2 prior to neuronal death. Restoring SV2 levels in these neurons reinstates synaptic release functions and rescues neuronal toxicity.

Solar irradiation (λ ≥ 290 nm) has been introduced into a traditional Fe2+ activated persulfate (PS) system (Fe2+/PS). The combination system of solar light, Fe2+ and PS system (solar/Fe2+/PS) exhibited a rapid and continuous oxidation of chloramphenicol (CAP) in solution, and showed great advantages over the Fe2+/PS process by accelerated degradation efficiency. A presumed reason is that Fe2+ was slowly and continuously recycled by solar light, and the reductive photolysis Fe3+ to Fe2+ was promoted concomitantly with the production of additional hydroxyl radical (HO ). The optimal dosages of PS and Fe2+ were determined by batch experiments. pH significantly influenced CAP degradation, and an acidic condition favored the reaction. Both HO and sulfate radical (SO4 −) were considered to be the mainly oxidant to remove CAP, and HO had a higher contribution than SO4 −. The presence of HCO3−, NO3−, NO2−, H2PO4−, HPO42− demonstrated adverse effects on CAP decay in solar/Fe2+/PS process. Coexisting Cl− ions slightly accelerated the CAP degradation rate at an appropriate concentration (0.6–6 mM) but gradually inhibited at a higher Cl− (12–36 mM) content. The results clearly showed that CAP presented the slowest degradation rate in wastewater, and the colloids should be taken into consideration prior to the application of solar/Fe2+/PS for wastewater treatment. Nonetheless, up to 89.7%, 94.7%, and 65.4% of CAP were removed from the filtrate, permeate, and retentate within 100 min, respectively. It is expected that the modified process could be applied for CAP removal from wastewater containing a considerable colloids/organic content. Finally, 8 major intermediate products were identified and the preliminary degradation pathways were proposed.

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two apparently distinct neurodegenerative diseases, the former characterized by selective loss of motor neurons in the brain and spinal cord and the latter characterized by selective atrophy of frontal and temporal lobes. Over the years, however, growing evidence from clinical, pathological and genetic findings has suggested that ALS and FTD belong to the same clinic-pathological spectrum disorder. This concept has been further supported by the identification of the most common genetic cause for both diseases, an aberrantly expanded hexanucleotide repeat GGGGCC sequence located in a non-coding region of the gene C9orf72. Three hypotheses have been proposed to explain how this repeats expansion causes diseases: 1) C9orf72 haploinsufficiency-expanded repeats interfere with transcription or translation of the gene, leading to decreased expression of C9orf72 protein; 2) RNA gain of function-RNA foci formed by sense and antisense transcripts of expanded repeats interact and sequester essential RNA binding proteins, causing neurotoxicity; 3) Repeat associated non-ATG initiated (RAN) translation of GGGGCC repeat expansion-RAN translation of expanded sense and antisense repeats produces potential toxic dipeptide repeat protein (DPR). In this review, we assess current evidence supporting or arguing against each proposed mechanism in C9 ALS/FTD disease pathogenesis. Additionally, controversial findings are also discussed. Lastly, we discuss the possibility that the three pathogenic mechanisms are not mutually exclusive and all three might be involved in disease.

SummaryAberrant hexanucleotide repeat expansions in C9orf72 are the most common genetic change underlying amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). RNA transcripts containing these expansions undergo repeat-associated non-ATG translation (RAN-T) to form five dipeptide repeat proteins (DPRs). DPRs are found as aggregates throughout the CNS of C9orf72-ALS/FTD patients, and some cause degeneration when expressed in vitro in neuronal cultures and in vivo in animal models. The spread of characteristic disease-related proteins drives the progression of pathology in many neurodegenerative diseases. While DPR toxic mechanisms continue to be investigated, the potential for DPRs to spread has yet to be determined. Using different experimental cell culture platforms, including spinal motor neurons derived from induced pluripotent stem cells from C9orf72-ALS patients, we found evidence for cell-to-cell spreading of DPRs via exosome-dependent and exosome-independent pathways, which may be relevant to disease.

An intronic GGGGCC repeat expansion in C9ORF72 is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), but the pathogenic mechanism of this repeat remains unclear. Using human induced motor neurons (iMNs), we found that repeat-expanded C9ORF72 was haploinsufficient in ALS. We found that C9ORF72 interacted with endosomes and was required for normal vesicle trafficking and lysosomal biogenesis in motor neurons. Repeat expansion reduced C9ORF72 expression, triggering neurodegeneration through two mechanisms: accumulation of glutamate receptors, leading to excitotoxicity, and impaired clearance of neurotoxic dipeptide repeat proteins derived from the repeat expansion. Thus, cooperativity between gain- and loss-of-function mechanisms led to neurodegeneration. Restoring C9ORF72 levels or augmenting its function with constitutively active RAB5 or chemical modulators of RAB5 effectors rescued patient neuron survival and ameliorated neurodegenerative processes in both gain- and loss-of-function C9ORF72 mouse models. Thus, modulating vesicle trafficking was able to rescue neurodegeneration caused by the C9ORF72 repeat expansion. Coupled with rare mutations in ALS2, FIG4, CHMP2B, OPTN and SQSTM1, our results reveal mechanistic convergence on vesicle trafficking in ALS and FTD.

The Patlak--Keller--Segel model can be used to model the nonlocal aggregation phenomena in the collective motion of cells or the evolution of the density of bacteria by chemotaxis. We consider the ...

SummaryExpanded GGGGCC (G4C2) nucleotide repeats within the C9ORF72 gene are the most common genetic mutation associated with both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Sense and antisense transcripts of these expansions are translated to form five dipeptide repeat proteins (DRPs). We employed primary cortical and motor neuron cultures, live-cell imaging, and transgenic fly models and found that the arginine-rich dipeptides, in particular Proline-Arginine (PR), are potently neurotoxic. Factors that anticipated their neurotoxicity included aggregation in nucleoli, decreased number of processing bodies, and stress granule formation, implying global translational dysregulation as path accountable for toxicity. Nuclear PR aggregates were also found in human induced motor neurons and postmortem spinal cord tissues from C9ORF72 ALS and ALS/FTD patients. Intronic G4C2 transcripts, but not loss of C9ORF72 protein, are also toxic to motor and cortical neurons. Interestingly, G4C2 transcript-mediated neurotoxicity synergizes with that of PR aggregates, suggesting convergence of mechanisms.