Early Spectral Evolution of the Rapidly Expanding Type Ia SN 2006X

We present optical spectroscopic and photometric observations of Type Ia supernova (SN) 2006X from --10 to +91 days after the $B$-band maximum. This SN exhibits one of the highest expansion velocity ever published for SNe Ia. At premaximum phases, the spectra show strong and broad features of intermediate-mass elements such as Si, S, Ca, and Mg, while the O{\sc i}$\lambda$7773 line is weak. The extremely high velocities of Si{\sc ii} and S{\sc ii} lines and the weak O{\sc i} line suggest that an intense nucleosynthesis might take place in the outer layers, favoring a delayed detonation model. Interestingly, Si{\sc ii}$\lambda$5972 feature is quite shallow, resulting in an unusually low depth ratio of Si{\sc ii}$\lambda$5972 to $\lambda$6355, $\cal R$(Si{\sc ii}). The low $\cal R$(Si{\sc ii}) is usually interpreted as a high photospheric temperature. However, the weak Si{\sc iii}$\lambda$4560 line suggests a low temperature, in contradiction to the low $\cal R$(Si{\sc ii}). This could imply that the Si{\sc ii}$\lambda$5972 line might be contaminated by underlying emission. We propose that $\cal R$(Si{\sc ii}) may not be a good temperature indicator for rapidly expanding SNe Ia at premaximum phases.Comment: 20 pages, 7 figures, (Received 2008 August 17; Accepted 2009 April 13

Biological responses according to the shape and size of carbon nanotubes in BEAS-2B and MESO-1 cells

This study aimed to investigate the influence of the shape and size of multi-walled carbon nanotubes (MWCNTs) and cup-stacked carbon nanotubes (CSCNTs) on biological responses in vitro. Three types of MWCNTs - VGCF (R)-X, VGCF (R)-S, and VGCF (R) (vapor grown carbon fibers; with diameters of 15, 80, and 150 nm, respectively) - and three CSCNTs of different lengths (CS-L, 20-80 mu m; CS-S, 0.5-20 mu m; and CS-M, of intermediate length) were tested. Human bronchial epithelial (BEAS-2B) and malignant pleural mesothelioma cells were exposed to the CNTs (1-50 mu g/mL), and cell viability, permeability, uptake, total reactive oxygen species/superoxide production, and intracellular acidity were measured. CSCNTs were less toxic than MWCNTs in both cell types over a 24-hour exposure period. The cytotoxicity of endocytosed MWCNTs varied according to cell type/size, while that of CSCNTs depended on tube length irrespective of cell type. CNT diameter and length influenced cell aggregation and injury extent. Intracellular acidity increased independently of lysosomal activity along with the number of vacuoles in BEAS-2B cells exposed for 24 hours to either CNT (concentration, 10 mu g/mL). However, total reactive oxygen species/superoxide generation did not contribute to cytotoxicity. The results demonstrate that CSCNTs could be suitable for biological applications and that CNT shape and size can have differential effects depending on cell type, which can be exploited in the development of highly specialized, biocompatible CNTs.ArticleINTERNATIONAL JOURNAL OF NANOMEDICINE. 9:1979-1990 (2014)journal articl

Toxicoproteomic evaluation of carbon nanomaterials in vitro

Carbon nanotubes (CNTs) have already been successfully implemented in various fields, and they are anticipated to have innovative applications in medical science. However, CNTs have asbestos-like properties, such as their nanoscale size and high aspect ratio (> 100). Moreover, CNTs may persist in the body for a long time. These properties are thought to cause malignant mesothelioma and lung cancer. However, based on conventional toxicity assessment systems, the carcinogenicity of asbestos and CNTs is unclear. The reason for late countermeasures against asbestos is that reliable, long-term safety assessments have not yet been developed by toxicologists. Therefore, a new type of long-term safety assessment, different from the existing methods, is needed for carbon nanomaterials. Recently, we applied a proteomic approach to the safety assessment of carbon nanomaterials. In this review, we discuss the basic concept of our approach, the results, the problems, and the possibility of a long-term safety assessment for carbon nanomaterials using the toxicoproteomic approach.ArticleJournal of Proteomics. 74(12):2703-2712 (2011)journal articl

DJ-1 as a potential biomarker for the development of biocompatible multiwalled carbon nanotubes

Hisao Haniu1, Tamotsu Tsukahara2, Yoshikazu Matsuda3, Yuki Usui4, Kaoru Aoki5, Masayuki Shimizu5, Nobuhide Ogihara5, Kazuo Hara5, Seiji Takanashi5, Masanori Okamoto5, Norio Ishigaki5, Koichi Nakamura5, Hiroyuki Kato5, Naoto Saito6 1Institute of Carbon Science and Technology, 2Department of Integrative Physiology and Bio-System Control, Shinshu University, Matsumoto, Nagano, 3Clinical Pharmacology Educational Center, Nihon Pharmaceutical University, Ina-machi, Saitama, 4Research Center for Exotic Nanocarbons, 5Department of Orthopaedic Surgery, 6Department of Applied Physical Therapy, Shinshu University School of Health Sciences, Shinshu University, Matsumoto, Nagano, Japan Background: In the present study, we investigated whether DJ-1 could serve as a biomarker for assessing the biocompatibility of multiwalled carbon nanotubes (MWCNTs), using the highly purified carbon nanotube, HTT2800. Methods: Using Western blot analysis, we determined DJ-1 protein levels in two different types of cells (one capable and the other incapable of HTT2800 endocytosis). Using quantitative real-time polymerase chain reaction, we also investigated the ability of purified nanotubes to alter DJ-1 mRNA levels. Results: We demonstrated that the DJ-1 protein concentration was reduced, regardless of the cytotoxic activity of intracellular HTT2800. Furthermore, HTT2800 decreased the DJ-1 mRNA levels in a dose-dependent manner. This decrease in DJ-1 mRNA levels was not observed in the case of Sumi black or cup-stacked carbon nanotubes. Conclusion: These data indicate that modification of DJ-1 expression is caused by the cell response to MWCNTs. We conclude that DJ-1 is a promising candidate biomarker for the development of biocompatible MWCNTs. Keywords: multiwalled carbon nanotubes, DJ-1 protein, Western blot, quantitative real-time polymerase chain reactio

Biocompatibility and bone tissue compatibility of alumina ceramics reinforced with carbon nanotubes

信州大学博士（医学）・学位論文・平成23年3月31日授与（甲第906号)・荻原伸英The addition of carbon nanotubes (CNTs) remarkably improves the mechanical characteristics of base materials. CNT/alumina ceramic composites are expected to be highly functional biomaterials useful in a variety of medical fields. Biocompatibility and bone tissue compatibility were studied for the application of CNT/alumina composites as biomaterials. Methods & results: Inflammation reactions in response to the composite were as mild as those of alumina ceramic alone in a subcutaneous implantation study. In bone implantation testing, the composite showed good bone tissue compatibility and connected directly to new bone. An in vitro cell attachment test was performed for osteoblasts, chondrocytes, fibroblasts and smooth muscle cells, and CNT/alumina composite showed cell attachment similar to that of alumina ceramic. Discussion & conclusion: Owing to proven good biocompatibility and bone tissue compatibility, the application of CNT/alumina composites as biomaterials that contact bone, such as prostheses in arthroplasty and devices for bone repair, are expected.ArticleNANOMEDICINE. 7(7):981-993 (2012)journal articl

Advanced application of bovine intestinal epithelial cell line for evaluating regulatory effect of lactobacilli against heat-killed enterotoxigenicEscherichia coli-mediated inflammation

Background: Previously, a bovine intestinal epithelial cell line (BIE cells) was successfully established. This work hypothesized that BIE cells are useful in vitro model system for the study of interactions of microbial- or pathogenassociated molecular patterns (MAMPs or PAMPs) with bovine intestinal epithelial cells and for the selection of immunoregulatory lactic acid bacteria (LAB). Results: All toll-like receptor (TLR) genes were expressed in BIE cells, being TLR4 one of the most strongly expressed. We demonstrated that heat-stable PAMPs of enterotoxigenic Escherichia coli (ETEC) significantly enhanced the production of IL-6, IL-8, IL-1! and MCP-1 in BIE cells by activating both NF-"B and MAPK pathways. We evaluated the capacity of several lactobacilli strains to modulate heat-stable ETEC PAMPs-mediated inflammatory response in BIE cells. Among these strains evaluated, Lactobacillus casei OLL2768 attenuated heat-stable ETEC PAMPs-induced pro-inflammatory response by inhibiting NF-"B and p38 signaling pathways in BIE cells. Moreover, L. casei OLL2768 negatively regulated TLR4 signaling in BIE cells by up-regulating Toll interacting protein (Tollip) and B-cell lymphoma 3-encoded protein (Bcl-3). Conclusions: BIE cells are suitable for the selection of immunoregulatory LAB and for studying the mechanisms involved in the protective activity of immunobiotics against pathogen-induced inflammatory damage. In addition, we showed that L. casei OLL2768 functionally modulate the bovine intestinal epithelium by attenuating heat-stable ETEC PAMPs-induced inflammation. Therefore L. casei OLL2768 is a good candidate for in vivo studying the protective effect of LAB against intestinal inflammatory damage induced by ETEC infection or heat-stable ETEC PAMPs challenge in the bovine host.Fil: Takanashi, Naoya. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Tomosada, Yohsuke. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Villena, Julio Cesar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Tucuman. Centro de Referencia Para Lactobacilos (i); Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Murata, Kozue. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Takahashi, Takuya. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Chiba, Eriko. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Tohno, Masanori. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan; National Agriculture and Food Research Organization. National Institute of Livestock and Grassland Science; Japan.;Fil: Tomoyuki Shimazu. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan; Laboratory of Animal Breading and Genetics. Graduate School of Agricultural Science; Japan.;Fil: Aso, Hisashi. Cell Biology Laboratory, Graduate School of Agricultural Science. Tohoku University; Japan.;Fil: Suda, Yoshihito. Department of Food, Agriculture and Environment. Miyagi University; Japan.;Fil: Ikegami, Shuji. Division of Research and Development. Food Science Institut. Meiji Dairies CoOdawara; Japan;Fil: Itoh, Hiroyuki. Division of Research and Development. Food Science Institut. Meiji Dairies CoOdawara; Japan;Fil: Kawai, Yasushi. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Tadao Saito. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan;Fil: Alvarez, Gladis Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán. Centro de Referencia para Lactobacilos (i); Argentina;Fil: Kitazawa, Haruki. Food and Feed Immunology Group. Laboratory of Animal Products Chemistry. Graduate School of Agricultural Science. Tohoku University; Japan

Elucidation mechanism of different biological responses to multi-walled carbon nanotubes using four cell lines

We examined differences in cellular responses to multi-walled carbon nanotubes (MWCNTs) using malignant pleural mesothelioma cells (MESO-1), bronchial epithelial cells (BEAS-2B), neuroblastoma cells (IMR-32), and monoblastic cells (THP-1), before and after differentiation. MESO-1, BEAS-2B and differentiated THP-1 cells actively endocytosed MWCNTs, resulting in cytotoxicity with lysosomal injury. However, cytotoxicity did not occur in IMR-32 or undifferentiated THP-1 cells. Both differentiated and undifferentiated THP-1 cells exhibited an inflammatory response. Carbon blacks were endocytosed by the same cell types without lysosomal damage and caused cytokine secretion, but they did not cause cytotoxicity. These results indicate that the cytotoxicity of MWCNTs requires not only cellular uptake but also lysosomal injury. Furthermore, it seems that membrane permeability or cytokine secretion without cytotoxicity results from several active mechanisms. Clarification of the cellular recognition mechanism for MWCNTs is important for developing safer MWCNTs.ArticleInternational Journal of Nanomedicine. 6(1):3487-3497 (2011)journal articl

Effect of dispersants of multi-walled carbon nanotubes on cellular uptake and biological responses

Although there have been many reports about the cytotoxicity of multi-walled carbon nanotubes (MWCNTs), the results are still controversial. To investigate one possible reason, the authors investigated the influence of MWCNT dispersants on cellular uptake and cytotoxicity. Cytotoxicity was examined (measured by alamarBlue® assay), as well as intracellular MWCNT concentration and cytokine secretion (measured by flow cytometry) in human bronchial epithelial cells (BEAS-2B) exposed to a type of highly purified MWCNT vapor grown carbon fiber (VGCF®, Shōwa Denkō Kabushiki-gaisha, Tokyo, Japan) in three different dispersants (gelatin, carboxylmethyl cellulose, and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine). The authors also researched the relationship between the intracellular concentration of MWCNTs and cytotoxicity by using two cell lines, BEAS-2B and MESO-1 human malignant pleural mesothelioma cells. The intracellular concentration of VGCF was different for each of the three dispersants, and the levels of cytotoxicity and inflammatory response were correlated with the intracellular concentration of VGCF. A relationship between the intracellular concentration of VGCF and cytotoxic effects was observed in both cell lines. The results indicate that dispersants affect VGCF uptake into cells and that cytotoxicity depends on the intracellular concentration of VGCF, not on the exposed dosage. Thus, toxicity appears to depend on exposure time, even at low VGCF concentrations, because VGCF is biopersistent