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Transient receptor potential ankyrin 1 (TRPA1) and vanilloid 1 (TRPV1) are thermosensitive channels that play an important role in thermal sensation or tooth pain by regulating intracellular Ca2+ concentration that is essential for pulp tissue repair. The aim of this study was to evaluate the role of TRPA1 and TRPV1 channels in the odontogenic differentiation of human dental pulp cells (HDPCs). HDPCs were isolated from healthy human intact third molars and cultured in odontogenic differentiation medium. Gene and protein expression levels of TRPA1 and TRPV1 channels during the odontogenic differentiation of HDPCs were evaluated by real-time quantitative polymerase chain reaction and Western blot analysis. HDPCs were then treated with channel agonists or antagonists, and the expression levels of odontogenic markers dentin sialophosphoprotein (DSPP) and osteopontin (OPN) were examined. Alkaline phosphatase activity and alizarin red staining were also conducted to detect mineralization levels. Consistent with the mineralization degree and DSPP and OPN expression, messenger RNA and protein expression of TRPA1 and TRPV1 channels was up-regulated during the odontogenic differentiation of HDPCs. The application of TRPA1 or TRPV1 agonists increased the mineralized nodules of alizarin red staining and alkaline phosphatase activity and up-regulated the messenger RNA and protein expression of DSPP and OPN, respectively, with the highest values reached on the seventh day (P <.05). On the contrary, the mineralization level and DSPP and OPN expression could be suppressed by using the antagonists of these 2 channels. TRPA1 and TRPV1 channels not only showed up-regulated expression along with the odontogenic differentiation of HDPCs but also could affect the odontogenic differentiation by regulating intracellular Ca2+ concentration. [ABSTRACT FROM AUTHOR]

• MOF-derived porous carbon fiber bundles/Y 2 Co 8 Fe 9 composites were prepared. • Good impedance and attenuation were obtained due to the synergetic effect. • The maximum RL of -64.79 dB and bandwidth of 5.02 GHz were obtained at 1.44mm. • A broad bandwidth of 6.52 GHz was acquired at 1.6 mm. • Absorption mechanisms were discussed. The development of broadband and thin electromagnetic wave absorbing materials is urgently required for use in practical applications. In this study, microwave absorption composites comprising Y 2 Co 8 Fe 9 and various weight ratios of metal-organic framework (MOF)-derived carbon fiber bundles (0%, 0.1%, 0.3%, 0.5%) were prepared. The composite filled with 0.1 wt% MOF-derived carbon fiber bundles had a minimum reflection loss (RL) of -64.79 dB at a thickness of 1.44 mm and an effective absorption bandwidth (with an RL of less than -10 dB) of 5.02 GHz. Furthermore, a wide effective absorption bandwidth of 6.52 GHz was also acquired at 1.6 mm. The microwave absorption performance was significantly enhanced owing to the improved impedance matching, as well as the synergetic effect between the dielectric loss and magnetic loss. This study provides a new paradigm for fabricating composites consisting of MOF-derived materials and rare-earth materials for thin and broadband microwave absorption performance. [Display omitted] [ABSTRACT FROM AUTHOR]

Chemokine-like factor 1(CKLF1) is a newly cloned cytokine with three RNA splicing isoforms. It has chemotactic activities on leukocytes and plays an important role in skeletal muscle regeneration. Here we have isolated two rat homologues of human chemokine-like factors by expressed sequence tag assembly, which are designated as rat chemokine-like factor 1 and 2 (rat CKLF1, CKLF2). The full-length cDNAs of rat CKLF1 and -2 contain 523 and 682 nucleotides and the open reading frames encoding 98 and 151 amino acids, respectively. Rat CKLF1 and -2 share about 54.1 and 59.6% homologies with human CKLF1 and -2 at the amino acid level; both rat CKLF1 and -2 contain a CX3C motif at their C-terminal regions while human CKLFs have a CC motif at the same regions. Rat CKLFs are highly expressed in testis, while human CKLFs have a broad expression spectrum across multiple tissues. Recombinant rat CKLF1 can be secreted into the cell culture supernatants and has chemotactic effects on neutrophils, macrophages and lymphocytes, which is similar to human CKLF1, while recombinant rat CKLF2 has weaker chemotactic effects on these cells. These findings show that rat CKLFs have similar bioactivity with human CKLFs, although they are different in tissue distribution and contain different characteristic motifs. [Copyright &y& Elsevier]

Chemokine-like factor 1 (CKLF1) is a novel cytokine first cloned from U937 cells. It contains different splicing forms and has chemotactic effects on a wide spectrum of cells both in vitro and in vivo; it can also stimulate the regeneration of skeletal muscle cells in vivo, but the mechanism remains unclear. To probe the myogenesis function of CKLF2, which is the largest isoform of CKLFs, C2C12 murine myoblasts were stably transfected with human CKLF2 eukaryotic expression vector. Compared with control vector transfected C2C12 cells, CKLF2 overexpression causes accelerated myoblast proliferation as determined by cell counting and [3H]TdR incorporation assays. In addition, CKLF2 overexpression also promotes cell differentiation, which was determined by higher expression levels of myogenin, creatine kinase, myosin and the accelerated myoblast fusion. Further analysis also indicates that CKLF2 could activate the transcription activity of the bHLH/MyoD and MEF2 families. Finally, DNA synthesis and myotube formation could also be promoted by growing C2C12 cells in conditioned media from CKLF2-transfected cells. These findings strongly suggest a role for human CKLF2 in regulation of skeletal muscle myogenesis. [Copyright &y& Elsevier]

Broadband microwave absorbing materials with a multilayer structure based on multi-walled carbon nanotubes (MWCNTs) as a filtering layer has been designed. The absorption curves of the multilayer structure change from a single peak to double peaks after the addition of the filtering layer. As a result, the effective microwave absorption bandwidth is broadened to 12.6 GHz with a total thickness of 2.3 mm. Normalized power flow and power loss distribution maps at fixed frequencies were analyzed by CST simulator. The broadening of the microwave absorption bandwidth is attributed to the electromagnetic wave selective filtering effect of the MWCNTs which contribute to impedance matching and microwave absorption at different frequencies. [ABSTRACT FROM AUTHOR]

Abstract: In this study we describe a method for highly specific enrichment of glycopeptides with boronic acid-functionalized chitosan polymeric nanospheres and matrix assisted laser desorption-ionization mass spectrometry (MALDI-MS). This is the first time chitosan has been used to create nanosphere support material for selective enrichment of glycopeptides by modification with glycidyl methacrylate (GMA) and derivatization with 3-aminophenylboronic acid (APB). Due to their multifunctional chemical moieties, these 20–100nm chitosan–GMA–APB nanospheres have unique properties, such as good dispersibility, good biocompatibility and chemical stability, as well as augmented specificity with glycopeptides. Enrichment conditions were optimized by using trypsin digested glycoprotein horseradish peroxidase. The high specificity of chitosan–GMA–APB nanospheres was demonstrated by effectively enriching glycopeptides from a digest mixture of horseradish peroxidase and nonglycoproteins (bovine serum albumin (BSA)). [Copyright &y& Elsevier]

Abstract: Apoptosis is a genetically determined cell suicidal program that plays critical roles in many physiological and pathological processes. In this study, we report the cloning and characterization of a novel human gene, nuclear apoptosis-inducing factor 1 (NAIF1), overexpression of which induces apoptosis in cells. Human NAIF1 is located on chromosome 9q34.11 and encodes 327 amino acids with a homeodomain-like region and two nuclear localization signals at its N-terminal region. NAIF1 is conserved across diverse species, including human, mouse, crab-eating macaque, dog, chicken and frog, and shares no obvious homology to any known genes or proteins. Northern blot analysis revealed wide expression of NAIF1 mRNA throughout human tissues. NAIF1 was predominantly localized in the nucleus. Overexpression of NAIF1 inhibited cell growth and induced apoptosis. Furthermore, NAIF1 transfection caused both decreases in mitochondrial membrane potential and caspase-3 activation. In summary, NAIF1 is a nuclear protein that induces apoptosis when overexpressed. [Copyright &y& Elsevier]