6 research outputs found
P-T-X-Phase Equilibrium and Strainmetric Scanning of Deviation from Stoichometry in Crystals in Semiconductor and Oxide Systems
Available from VNTIC / VNTIC - Scientific & Technical Information Centre of RussiaSIGLERURussian Federatio
SQSTM1 gene sequencing in frontotemporal lobar degeneration and Amyotrophic Lateral Sclerosis
OBJECTIVE: There is increasing evidence that common genetic risk factors underlie frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). Recently, mutations in the sequestosome 1 (SQSTM1) gene, which encodes p62 protein, have been reported in patients with ALS. P62 is a multifunctional adapter protein mainly involved in selective autophagy, oxidative stress response, and cell signaling pathways. The purpose of our study was to evaluate the frequency of SQSTM1 mutations in a dataset of unrelated patients with FTLD or ALS, in comparison with healthy controls and patients with Paget disease of bone (PDB). METHODS: Promoter region and all exons of SQSTM1 were sequenced in a large group of subjects, including patients with FTLD or ALS, healthy controls, and patients with PDB. The clinical characteristics of patients with FTLD or ALS with gene mutations were examined. RESULTS: We identified 6 missense mutations in the coding region of SQSTM1 in patients with either FTLD or ALS, none of which were found in healthy controls or patients with PDB. In silico analysis suggested a pathogenetic role for these mutations. Furthermore, 7 novel noncoding SQSTM1 variants were found in patients with FTLD and patients with ALS, including 4 variations in the promoter region. CONCLUSIONS: SQSTM1 mutations are present in patients with FTLD and patients with ALS. Additional studies are warranted in order to better investigate the role of p62 in the pathogenesis of both FTLD and ALS
Investigation of C9orf72 in 4 neurodegenerative disorders
OBJECTIVE: To estimate the allele frequency of C9orf72 (G(4)C(2)) repeats in amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration (FTLD), Alzheimer disease (AD), and Parkinson disease (PD). DESIGN: The number of repeats was estimated by a 2-step genotyping strategy. For expansion carriers, we sequenced the repeat flanking regions and obtained APOE genotypes and MAPT H1/H2 haplotypes. SETTING: Hospitals specializing in neurodegenerative disorders. SUBJECTS: We analyzed 520 patients with FTLD, 389 patients with ALS, 424 patients with AD, 289 patients with PD, 602 controls, 18 families, and 29 patients with PD with the LRRK2 G2019S mutation. MAIN OUTCOME MEASURE: The expansion frequency. RESULTS: Based on a prior cutoff (>30 repeats), the expansion was detected in 9.3% of patients with ALS, 5.2% of patients with FTLD, and 0.7% of patients with PD but not in controls or patients with AD. It was significantly associated with family history of ALS or FTLD and age at onset of FTLD. Phenotype variation (ALS vs FTLD) was not associated with MAPT, APOE, or variability in the repeat flanking regions. Two patients with PD were carriers of 39 and 32 repeats with questionable pathological significance, since the 39-repeat allele does not segregate with PD. No expansion or intermediate alleles (20–29 repeats) were found among the G2019S carriers and AD cases with TAR DNA-binding protein 43–positive inclusions. Surprisingly, the frequency of the 10-repeat allele was marginally increased in all 4 neurodegenerative diseases compared with controls, indicating the presence of an unknown risk variation in the C9orf72 locus. CONCLUSIONS: The C9orf72 expansion is a common cause of ALS and FTLD, but not of AD or PD. Our study raises concern about a reliable cutoff for the pathological repeat number, which is important in the utility of genetic screening
Subwavelength integrated photonics
The availability of nanometer scale fabrication techniques has inspired scientists to investigate subwavelength-structured metamaterials with engineered optical properties. Metamaterial waveguide devices are becoming established as fundamental building blocks for the next generation photonic integrated circuits. Here we present an overview of recent advances in this surging field, including metamaterial fiber-chip couplers, ultra-broadband telecom devices, biosensors and astrophotonic spectral filters. We will review how optical metamaterials will enhance the performance of the next generation of integrated photonic devices and we explore some of the arising challenges encountered in the transition from concept demonstration to viable technology