Influence of Chemical Structure on the Refractive Index of Imide‐Type Polymers

The influence of different substituents on the optical properties of poly(amide imide)s and polyimides is systematically investigated. All of the polymers exhibit good solubility and film‐forming ability, high thermal stability, and glass transition temperatures of 162–209 °C for poly(amide imide)s and of 209–274 °C for polyimides. The optical transmittance of the films at 450 nm is above 80% for all the studied polyimides and poly(amide imide)s containing benzonitrile units linked in the 2,6‐position. The values of refractive index for poly(amide imide)s are in the range of 1.623–1.748 and for polyimides in the domain of 1.672–1.768.

     

Phosphoinositide Signaling in Unicellular Eukaryotes

The review considers the up to date achievements in the role of membrane phosphoinositides and keys enzymes of the lipid branch of the phosphoinositide signal pathway (PI-pathway) in unicellular eukaryotes. Particular attention is paid to mechanisms of phospholipase C (PLC) activation and the PLC interaction both with cell surface receptors and with the effector cytoplasm targets. The role of protein kinase C (PKC) in intracellular signaling and the relationship of the PI-pathway key enzymes with protein tyrosine kinases (PTK)-signaling and cAMP-protein kinase A (PKA) pathway are discussed.     

Recurrent pre‐existing and acquired DNA copy number alterations,including focal TERT gains,in neuroblastoma central nervous system metastases

Stage 4 neuroblastomas have a high rate of local and metastatic relapse and associated disease mortality. The central nervous system (CNS) is currently one of the most common isolated relapse sites, yet the genomic alterations that contribute to these metastases are unknown. This study sought to identify recurrent DNA copy number alterations (CNAs) and target genes relating to neuroblastoma CNS metastases by studying 19 pre‐CNS primary tumors and 27 CNS metastases, including 12 matched pairs. SNP microarray analyses revealed that MYCN amplified (MYCNA) tumors had recurrent CNAs different from non‐MYCNA cohorts. Several CNAs known to be prevalent among primary neuroblastomas occurred more frequently in CNS metastases, including 4p?, 7q+, 12q+, and 19q? in non‐MYCNA metastases, and 9p? and 14q? irrespective of MYCNA status. In addition, novel CNS metastases‐related CNAs included 18q22.1 gains in non‐MYCNA pre‐CNS primaries and 5p15.33 gains and 15q26.1→tel losses in non‐MYCNA CNS metastases. Based on minimal common regions, gene expression, and biological properties, TERT (5p), NR2F2 (15q), ALDH1A3 (15q), CDKN2A (9p), and possibly CDH7 and CDH19 (18q) were candidate genes associated with the CNS metastatic process. Notably, the 5p15 minimal common region contained only TERT, and non‐MYCNA CNS metastases with focal 5p15 gains had increased TERT expression, similar to MYCNA tumors. These findings suggest that a specific genomic lesion (18q22.1 gain) predisposes to CNS metastases and that distinct lesions are recurrently acquired during metastatic progression. Among the acquired lesions, increased TERT copy number and expression appears likely to function in lieu of MYCNA to promote CNS metastasis. © 2013 Wiley Periodicals, Inc.     

Interferon-β Production via Dectin-1-Syk-IRF5 Signaling in Dendritic Cells Is Crucial for Immunity to C. albicans

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Functional tongue and floor of mouth reconstruction with a chimeric flap after total glossectomy

Oral and Maxillofacial Surgery - Presently, the functional reconstruction of the tongue in patients after subtotal or total glossectomy with the removal of the oral floor muscles and spearing of...     

Enzymatic synthesis and electrochemical characterization of sodium 1,2-naphthoquinone-4-sulfonate-doped PEDOT/MWCNT composite

The development of novel materials with improved functional characteristics for supercapacitor electrodes is of current concern and calls for elaboration of innovative approaches. We report on an eco-friendly enzymatic synthesis of a composite based on poly(3,4-ethylenedioxythiophene) (PEDOT) and multi-walled carbon nanotubes (MWCNTs). The redox active compound, sodium 1,2-naphthoquinone-4-sulfonate (NQS), was used as a dopant for the backbone of the polymer. Oxidative polymerization of 3,4-ethylenedioxythiophene (EDOT) was catalyzed by a high redox potential laccase from the fungus Trametes hirsuta. Atmospheric oxygen served as an oxidant. A uniform thin layer of NQS-doped PEDOT formed on the surface of MWCNTs as a result of the enzymatic polymerization. The PEDOT–NQS/MWCNT composite showed a high specific capacitance of ca. 575 F g⁻¹ at a potential scan rate of 5 mV s⁻¹ and an excellent cycling stability within a potential window between −0.5 and 1.0 V, which makes it a promising electrode material for high-performance supercapacitors.

The use of redox active NSQ as a dopant of PEDOT dramatically increases the specific capacitance and cyclic stability of enzymatically synthesized PEDOT–NSQ/MWCNT composite.