Expansion of Human-Specific GGC Repeat in Neuronal Intranuclear Inclusion Disease-Related Disorders.

Neuronal intranuclear inclusion disease (NIID) is a slowly progressing neurodegenerative disease characterized by eosinophilic intranuclear inclusions in the nervous system and multiple visceral organs. The clinical manifestation of NIID varies widely, and both familial and sporadic cases have been reported. Here we have performed genetic linkage analysis and mapped the disease locus to 1p13.3-q23.1; however, whole-exome sequencing revealed no potential disease-causing mutations. We then performed long-read genome sequencing and identified a large GGC repeat expansion within human-specific NOTCH2NLC. Expanded GGC repeats as the cause of NIID was further confirmed in an additional three NIID-affected families as well as five sporadic NIID-affected case subjects. Moreover, given the clinical heterogeneity of NIID, we examined the size of the GGC repeat among 456 families with a variety of neurological conditions with the known pathogenic genes excluded. Surprisingly, GGC repeat expansion was observed in two Alzheimer disease (AD)-affected families and three parkinsonism-affected families, implicating that the GGC repeat expansions in NOTCH2NLC could also contribute to the pathogenesis of both AD and PD. Therefore, we suggest defining a term NIID-related disorders (NIIDRD), which will include NIID and other related neurodegenerative diseases caused by the expanded GGC repeat within human-specific NOTCH2NLC.

ABCC2 rs2273697 is associated with valproic acid concentrations in patients with epilepsy on valproic acid monotherapy.

Valproic acid (VPA), a widely used antiepileptic drug, is characterized by intensive inter-individual variability in concentration. Both efflux and influx transporters are reported to play important roles in the disposition of VPA, however, no comprehensive investigation into the association of the single nucleotide polymorphism (SNP) in ABC/SLC families with VPA concentration are reported. In the present study, we investigated the association of 12 SNPs in ABCC2, ABCC4, ABCG2, MCT1, MCT2, and OATP2B1 in 187 Chinese patients with epilepsy on VPA monotherapy with the trough concentrations of VPA. The data showed that VPA concentration in patients with ABCC2 rs2273697 AA genotype was significantly higher than that in those with GA+GG genotypes (p=0.000). The findings of the present study suggest that ABCC2 polymorphisms influence VPA concentrations in patients with epilepsy on VPA monotherapy, which may affect the treatment outcomes.

[Roles of axonal transport affected by K141N mutant HSP22 in the pathogenesis of CMT2L].

OBJECTIVE: To compare the axonal transport of wild-type (WT) and K141N mutant HSP22 in transfected primary cultured cortical neurons. METHODS: The plasmid (pCAGGS-HA-wtHSP22 or pCAGGS-HA-K141NHSP22) with WT or K141N mutant HSP22 gene and a GFP-expressing plasmid (pEGFP-N1) were co-transfected respectively into primary cultured cortical neurons. The axonal transport of WT and K141N mutant HSP22 was observed. And the distance traveled by WT and K141N mutant HSP22 was analyzed. RESULTS: The WT HSP22 was transported within axons and uniformly present throughout the entire length of axons. K141N mutant HSP22 failed to be transported to the same extent and was present only in cell body and proximal portion of axons. Analysis of distance traveled revealed that WT HSP22 traveled significantly further than the K141N mutant HSP22. CONCLUSION: The axonal transport of K141N mutant HSP22 may play an important role in the pathogenesis of CMT2L.

Mutations in GBA, SNCA, and VPS35 are not associated with Alzheimer's disease in a Chinese population: a case-control study.

SNCA, GBA, and VPS35 are three common genes associated with Parkinson's disease. Previous studies have shown that these three genes may be associated with Alzheimer's disease (AD). However, it is unclear whether these genes increase the risk of AD in Chinese populations. In this study, we used a targeted gene sequencing panel to screen all the exon regions and the nearby sequences of GBA, SNCA, and VPS35 in a cohort including 721 AD patients and 365 healthy controls from China. The results revealed that neither common variants nor rare variants of these three genes were associated with AD in a Chinese population. These findings suggest that the mutations in GBA, SNCA, and VPS35 are not likely to play an important role in the genetic susceptibility to AD in Chinese populations. The study was approved by the Ethics Committee of Xiangya Hospital, Central South University, China on March 9, 2016 (approval No. 201603198).

Associations of multiple visual rating scales based on structural magnetic resonance imaging with disease severity and cerebrospinal fluid biomarkers in patients with Alzheimer's disease.

The relationships between multiple visual rating scales based on structural magnetic resonance imaging (sMRI) with disease severity and cerebrospinal fluid (CSF) biomarkers in patients with Alzheimer's disease (AD) were ambiguous. In this study, a total of 438 patients with clinically diagnosed AD were recruited. All participants underwent brain sMRI scan, and medial temporal lobe atrophy (MTA), posterior atrophy (PA), global cerebral atrophy-frontal sub-scale (GCA-F), and Fazekas rating scores were visually evaluated. Meanwhile, disease severity was assessed by neuropsychological tests such as the Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Clinical Dementia Rating (CDR). Among them, 95 patients were tested for CSF core biomarkers, including Aß1-42, Aß1-40, Aß1-42/Aß1-40, p-tau, and t-tau. As a result, the GCA-F and Fazekas scales showed positively significant correlations with onset age (r = 0.181, p < 0.001; r = 0.411, p < 0.001, respectively). Patients with late-onset AD (LOAD) showed higher GCA-F and Fazekas scores (p < 0.001, p < 0.001). With regard to the disease duration, the MTA and GCA-F were positively correlated (r = 0.137, p < 0.05; r = 0.106, p < 0.05, respectively). In terms of disease severity, a positively significant association emerged between disease severity and the MTA, PA GCA-F, and Fazekas scores (p < 0.001, p < 0.001, p < 0.001, p < 0.05, respectively). Moreover, after adjusting for age, gender, and APOE alleles, the MTA scale contributed to moderate to severe AD in statistical significance independently by multivariate logistic regression analysis (p < 0.05). The model combining visual rating scales, age, gender, and APOE alleles showed the best performance for the prediction of moderate to severe AD significantly (AUC = 0.712, sensitivity = 51.5%, specificity = 84.6%). In addition, we observed that the MTA and Fazekas scores were associated with a lower concentration of Aß1-42 (p < 0.031, p < 0.022, respectively). In summary, we systematically analyzed the benefits of multiple visual rating scales in predicting the clinical status of AD. The visual rating scales combined with age, gender, and APOE alleles showed best performance in predicting the severity of AD. MRI biomarkers in combination with CSF biomarkers can be used in clinical practice.

The Protective Effects of Osteocyte-Derived Extracellular Vesicles Against Alzheimer's Disease Diminished with Aging.

Both Alzheimer's disease (AD) and osteoporosis (OP) are common age-associated degenerative diseases and are strongly correlated with clinical epidemiology. However, there is a lack of clear pathological relationship between the brain and bone in the current understanding. Here, it is found that young osteocyte, the most abundant cells in bone, secretes extracellular vesicles (OCYYoung -EVs) to ameliorate cognitive impairment and the pathogenesis of AD in APP/PS1 mice and model cells. These benefits of OCYYoung -EVs are diminished in aged osteocyte-derived EVs (OCYAged -EVs). Based on the self-constructed OCY-EVs tracer transgenic mouse models and the in vivo fluorescent imaging system, OCY-EVs have been observed to be transported to the brain under physiological and pathological conditions. In the hippocampal administration of Aß40 induced young AD model mice, the intramedullary injection of Rab27a-shRNA adenovirus inhibits OCYYoung -EVs secretion from bone and aggravates cognitive impairment. Proteomic quantitative analysis reveals that OCYYoung -EVs, compared to OCYAged -EVs, enrich multiple protective factors of AD pathway. The study uncovers the role of OCY-EV as a regulator of brain health, suggesting a novel mechanism in bone-brain communication.

TGM6 identified as a novel causative gene of spinocerebellar ataxias using exome sequencing.

Autosomal-dominant spinocerebellar ataxias constitute a large, heterogeneous group of progressive neurodegenerative diseases with multiple types. To date, classical genetic studies have revealed 31 distinct genetic forms of spinocerebellar ataxias and identified 19 causative genes. Traditional positional cloning strategies, however, have limitations for finding causative genes of rare Mendelian disorders. Here, we used a combined strategy of exome sequencing and linkage analysis to identify a novel spinocerebellar ataxia causative gene, TGM6. We sequenced the whole exome of four patients in a Chinese four-generation spinocerebellar ataxia family and identified a missense mutation, c.1550T-G transition (L517W), in exon 10 of TGM6. This change is at a highly conserved position, is predicted to have a functional impact, and completely cosegregated with the phenotype. The exome results were validated using linkage analysis. The mutation we identified using exome sequencing was located in the same region (20p13-12.2) as that identified by linkage analysis, which cross-validated TGM6 as the causative spinocerebellar ataxia gene in this family. We also showed that the causative gene could be mapped by a combined method of linkage analysis and sequencing of one sample from the family. We further confirmed our finding by identifying another missense mutation c.980A-G transition (D327G) in exon seven of TGM6 in an additional spinocerebellar ataxia family, which also cosegregated with the phenotype. Both mutations were absent in 500 normal unaffected individuals of matched geographical ancestry. The finding of TGM6 as a novel causative gene of spinocerebellar ataxia illustrates whole-exome sequencing of affected individuals from one family as an effective and cost efficient method for mapping genes of rare Mendelian disorders and the use of linkage analysis and exome sequencing for further improving efficiency.

Improving the diagnosis of AUS/FLUS thyroid nodules using an algorithm with combination of BRAFV600E mutation analysis and ultrasound pattern-based risk stratification.

PURPOSE: To propose a diagnostic algorithm for improving the diagnosis of atypia of undetermined significance or follicular lesion of undetermined significance (AUS/FLUS) thyroid nodules. METHODS: This study retrospectively enrolled 77 consecutive patients with 81 AUS/FLUS nodules who underwent preoperative BRAFV600E mutation analysis. A new diagnostic algorithm was proposed that BRAFV600E mutation analysis for the Fine-needle aspiration cytology specimen was firstly carried out, in which positive BRAFV600E mutation indicated malignancy and classification of the nodules with negative BRAFV600E mutation was further performed based on ultrasound pattern-based risk stratification of American Thyroid Association Guidelines. The diagnostic performance of the new diagnostic algorithm was evaluated. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, accuracy, and area under the receiver operating characteristic curve (AUROC) of new diagnostic algorithm were 94.6%, 84.0%, 91.4%, 86.9%, 90.1%, and 0.893, respectively. The proposed diagnostic algorithm significantly increased the diagnostic performances (AUROC: 0.893 vs. 0.837 and 0.795), sensitivity (94.6% vs. 71.4% and 75.0%), and accuracy (90.1% vs. 79.0% and 77.8%) compared with BRAFV600E mutation analysis alone and ultrasound pattern-based risk stratification alone (all P < 0.05). CONCLUSION: The proposed diagnostic algorithm is helpful for improving the diagnosis of AUS/FLUS nodules, which might be as a routine approach.

[Polynucleotide repeat expansion of nine spinocerebellar ataxia subtypes and dentatorubral-pallidoluysian atrophy in healthy Chinese Han population].

OBJECTIVE: To assist the establishment of platform and provide the reference standard for mutation detection in spinocerebellar ataxia (SCA) subtypes 1, 2, 3, 6, 7, 8, 10, 12, 17 and dentatorubral-pallidoluysian atrophy (DRPLA) in Chinese Han population. METHODS: The nucleotide repeat numbers of the 9 SCA subtypes and DRPLA were detected using fluorescence-PCR and capillary gel electrophoresis technique in 300 healthy Chinese Han individuals. RESULTS: Among the 300 healthy controls, the range of the CAG trinucleotide repeat number was 17 to 35 in SCA1, 14-28 in SCA2, 13-41 in SCA3/MJD, 4-16 in SCA6, 5-17 in SCA7, 5-21 in SCA12, 23-41 in SCA17, and 12-33 in DRPLA; and the range of CTA/CTG trinucleotide repeat number on SCA8 locus was 12-43 and the range of ATTCT pentanucleotide repeat number on SCA10 locus was 9-32. Of which, the 12 CTA/CTG repeats of SCA8, 9 ATTCT repeats of SCA10, 23 CAG repeats of SCA17 were the shortest normal repeat number, while the 41 CAG repeats of SCA3/MJD, 32 CAG repeats of SCA10 were the largest normal number that have not been reported. CONCLUSION: The normal ranges of polynucleotide repeats of different subtypes of SCA vary with geographical areas and ethnicities. It might be associated with the genetic and ethnic backgrounds. This is the first normal reference standard of polynucleotide repeat number of these ten SCA subtypes in Chinese Han.

Effectiveness of Combined Immunoglobulin and Glucocorticoid Treatments in a Patient With Stiff Limb Syndrome: Case Report and Review of the Literature.

Stiff limb syndrome (SLS) is a rare autoimmune-related central nervous system disorder, resulting in stiffness and spasms of limbs since onset with rare involvement of the truncal muscles. However, SLS patients will gain notable effects by appropriate therapy focusing on symptomatic treatment and immunotherapy. We reported on a 55-year-old female who showed typical painful spasms in both lower limbs and abduction of the right eyeball that partially responded to low-dose diazepam and had high-titer anti-glutamic acid decarboxylase (anti-GAD) antibody. Electromyography (EMG) only showed continuous motor unit activity (CMUA) in the anterior tibialis and right triceps. Eventually, our patient was diagnosed with SLS and treated with intravenous immunoglobulin (IVIG) and glucocorticoid combined simultaneously. She obtained notable effects. We also review and summarize the current literature on clinical characteristics, coexisting disease, treatment, and outcome of 40 patients with SLS. We hope that this report will provide a basis for further understanding of SLS and promote the formation of more advanced diagnosis and treatment processes.

Novel mutations of the SPG11 gene in hereditary spastic paraplegia with thin corpus callosum.

BACKGROUND: Hereditary spastic paraplegia with thin corpus callosum (HSP-TCC) is a clinically and genetically heterogeneous neurodegenerative disorder with genetic linkage to multi-loci. Recently pathogenic mutations in the KIAA1840 (now named SPG11) for SPG11, the major HSP-TCC locus, were identified; at least 42 different mutations have been detected. OBJECTIVE: To study the clinical features and identify the SPG11 gene mutations in Chinese patients with HSP-TCC. METHODS: Three kindreds with an autosomal recessive HSP-TCC and 5 cases with sporadic HSP-TCC in Chinese Hans were recruited. Detailed clinical history, neurological examination, MRI, electromyography, Mini Mental State Examination (MMSE), Spastic Paraplegia Rating Scale (SPRS) were presented. DNA samples of the 8 families were collected and mutation analysis of SPG11 gene was carried out by direct DNA sequencing. RESULTS: Except for one patient whose age at onset was 3 years old, 10 patients manifested a relatively similar combination of adolescence-onset cognitive decline and spastic paraparesis with TCC on brain MRI. We identified 10 novel and one known mutations in our 8 HSP-TCC families, which were two nonsense mutations (c.5977C>T/p.Q1993X, c.4668T>A/p.Y1556X), three small deletions (c.6898_6899delCT/p.L2300AfsX2338, c.3719_3720delTA/p.I1240VfsX263, c.733_734delAT/p.M245VfsX246), four small insertions (c.7088_7089insATTA/p.Y2363X, c.2163_2164insT/p.I722YfsX731, c.7101_7102insT/p.K2368X, c.6790_6791insC/p.L2264PfsX2339), one deletion/insertion (c.654_655delinsG/p.S218RfsX219), and one splice mutation (c.7151+4_7151+7delAGTA/p.K2384fsX2386). Each family has a different mutation and all the mutations are predicted to cause early protein truncation. CONCLUSION: This study widens the mutation spectrum of the SPG11 gene and the mutations in the SPG11 gene are also the major causative gene for HSP-TCC in the Chinese Hans. Screening of the whole gene is recommended in clinical practice.

[The advances in research on phosphorylation of polyglutamine disease].

Polyglutamine (polyQ) diseases are a group of hereditary neurodegenerative disorders caused by expansion of a glutamine repeat in responsible gene products. To date, the pathogenesis of polyQ diseases is still not very clear, but many researches suggest that phosphorylation of mutant proteins plays a critical role on the process of Huntington's disease, dentatorubral-pallidoluysian atrophy, spinal bulbar muscular atrophy, spinocerebellar ataxia1 and spinocerebellar ataxia 3/Machado-Joseph disease.

Multinodule abnormalities of the tracheobronchus: bronchoscopy findings and clinical diagnosis.

BACKGROUND AND AIMS: Bronchoscopy is an important method for diagnosing respiratory disease. Multiple tracheobronchial nodules are rarely reported and their causes remain unclear. OBJECTIVES: The aim of this study was to describe the clinical characteristics of multiple nodule tracheobronchial abnormalities found under bronchoscopy caused by different diseases. METHODS: Eighty-seven patients with multiple tracheobronchial nodules were enrolled in this study. The characteristics of the multinodule lesions and the patient were diagnosed based on the pathology findings in our hospital. Chest computed tomography images were retrospectively reviewed by pulmonologists and radiologist. RESULTS: In 55 patients with definite pathological diagnosis, 16 (29%) patients were diagnosed as tuberculosis (TB) granuloma; 23 (41.8%) cases were diagnosed as malignant disease; 12 (21.8%) cases were diagnosed as tracheobronchopathia osteochondroplastica; 2 (3.6%) cases were diagnosed as sarcoidosis; and one case (1.8%) was diagnosed as lymphoma and one case (1.8%) as fungal infection. There were 32 cases of chronic inflammation. There was no relationship between nodule distribution and the pathological diagnosis. Malignant nodules usually smaller with a pale outlook, while nodules with larger size and smooth and intact mucosa usually turn out to be granuloma of unknown reason. CONCLUSION: The major causes of mutinodule lesions observed using bronchoscopy are tumor and TB. The presence of multiple endotracheobronchial nodules suggest that pulmonary lesion is present, and biopsy should be performed. Malignant nodules can be diagnosed by appearance and biopsy. Pathology results of TB, sarcoidosis and fungal infection can turn out to be granuloma of unknown reason. Further diagnosis needs other clinical materials.

C9orf72 mutation is rare in Alzheimer's disease, Parkinson's disease, and essential tremor in China.

GGGGCC repeat expansions in the C9orf72 gene have been identified as a major contributing factor in patients with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Given the overlapping of clinical phenotypes and pathological characteristics between these two diseases and Alzheimer's disease (AD), Parkinson's disease (PD), and essential tremor (ET), we speculated regarding whether C9orf72 repeat expansions also play a major role in these three diseases. Using the repeat-primed polymerase chain reaction method, we screened for C9orf72 in three groups of patients with PD (n = 911), AD (n = 279), and ET (n = 152) in the Chinese Han population. There were no pathogenic repeats (>30 repeats) detected in either the patients or controls (n = 314), which indicated that the pathogenic expansions of C9orf72 might be rare in these three diseases. However, the analysis of the association between the number of repeats (p = 0.001), short/intermediate genotype (short: <7 repeats; intermediate: ≥7 repeats) (odds ratio 1.37 [1.05, 1.79]), intermediate/intermediate genotype (Odds ratio 2.03 [1.17, 3.54]), and PD risks indicated that intermediate repeat alleles could act as contributors to PD. To the best of our knowledge, this study is the first to reveal the correlation between C9orf72 and Chinese PD, AD, or ET patients. Additionally, the results of this study suggest the novel idea that the intermediate repeat allele in C9orf72 is most likely a risk factor for PD.

SUMO-1 modification on K166 of polyQ-expanded ataxin-3 strengthens its stability and increases its cytotoxicity.

Post-translational modification by SUMO was proposed to modulate the pathogenesis of several neurodegenerative diseases. Spinocerebellar ataxia type 3/Machado-Joseph disease (SCA3/MJD) is an autosomal dominant neurodegenerative disease caused by polyQ-expanded ataxin-3. We have previously shown that ataxin-3 was a new target of SUMOylation in vitro and in vivo. Here we identified that the major SUMO-1 binding site was located on lysine 166. SUMOylation did not influence the subcellular localization, ubiquitination or aggregates formation of mutant-type ataxin-3, but partially increased its stability and the cell apoptosis. Our findings revealed the role of ataxin-3 SUMOylation in SCA3/MJD pathogenesis.

Inclusion interaction of chloramphenicol and heptakis (2,6-di-O-methyl)-ß-cyclodextrin: phase solubility and spectroscopic methods.

The inclusion interaction between chloramphenicol and heptakis (2,6-di-O-methyl)-ß-cyclodextrin (DMBCD) had been investigated by phase solubility and spectroscopic methods such as UV-vis spectroscopy, circular dichroism, Fourier transform infrared (FT-IR) spectroscopy, proton nuclear magnetic resonance spectroscopy ((1)H NMR) as well as 2D-ROESY spectra. Phase solubility analysis showed A(L)-type diagram with DMBCD, which suggested the formation of 1:1 inclusion complex of DMBCD with chloramphenicol. The estimated stability constant (K(s)) of the inclusion complex of chloramphenicol with DMBCD is 493 M(-1) at 293 K. The solubility enhancement of chloramphenicol in the presence of DMBCD is stronger than that in the presence of ß-CD, HP-ß-CD and M-ß-CD. The results obtained by spectroscopic methods showed that the nitrophenyl moiety of chloramphenicol is deeply inserted into inner cavity of DMBCD from the narrow rim of DMBCD, which the inclusion model of chloramphenicol with DMBCD differs from that with ß-CD.