Matrix Model for Dirichlet Open String

We discuss the open string ending on D $p$-branes in IKKT framework. First we determine the boundary conditions of Green-Schwarz superstring which are consistent with supersymmetry and $\kappa$-symmetry. We point out some subtleties arising from taking the Schild gauge and show that in this gauge the system incorporates the limited dimensional D $p$-branes ($p=3,7$). The matrix regularization for the Dirichlet open string is given by gauge group SO(N). When $p=3$, the matrix model becomes the dimensional reduction of a 6 dimensional ${\cal N}=1$ super Yang-Mills theory.Comment: 9 pages, LaTe

Long-term histological comparison between near-infrared irradiated skin and scar tissues

Yohei Tanaka1,2, Kiyoshi Matsuo1, Shunsuke Yuzuriha11Department of Plastic and Reconstructive Surgery, Shinshu University School of Medicine, Matsumoto, Japan; 2Clinica Tanaka Plastic and Reconstructive Surgery and Anti-aging Center, Matsumoto, JapanBackground and objective: Our previous histological studies indicated that near-infrared (NIR) irradiation stimulates collagen proliferation in rat and human skin for 3 months. High collagen density in the dermis and smoothing of the epidermis were observed in irradiated rat skin, and appeared to last up to 6 months. Epidermal smoothness in irradiated rat skin seems to resemble scarring. Here, we performed a long-term histological comparison between NIR (1100 to 1800 nm) irradiated skin and scar tissues.Materials and methods: Rat skin was irradiated using a NIR device. Scar tissues were harvested from wounded areas and were compared with irradiated skin. Histological changes up to 180 days post-treatment were evaluated with hematoxylin and eosin, Azan-Mallory staining, and collagen type I and III staining.Results: In nonirradiated control skin, the dermis showed a low density of type I and III collagen, the surface of the epidermis was rough, and no significant changes were observed over time. In irradiated skin, both type I and III collagen increased significantly, and persisted up to 180 days. The density of type I collagen was significantly higher than that of type III collagen, whereas type I and III collagen of the control group did not differ significantly. Epidermis was thickened for 30 days, and epidermal smoothness persisted up to 180 days. In scar tissues, the density of type III collagen was higher than that of type I collagen. The number of fibroblasts remained high and the glial fibrils were dense until 180 days after injury compared with irradiated skin. Significant increases in both type I and III collagen and epidermal flattering persisted until 180 days.Conclusions: NIR irradiation induced high collagen density in the dermis, resulting in long-term epidermal smoothness without scar formation. Results indicated that NIR irradiation provides safe, consistent, and long-term effects of skin rejuvenation.Keywords: near-infrared irradiation, long-term effects, collagen, scar, skin rejuvenatio

Interaction between a Unique Minor Protein and a Major Capsid Protein of Bluetongue Virus Controls Virus Infectivity.

Among the Reoviridae family of double-stranded RNA viruses, only members of the Orbivirus genus possess a unique structural protein, termed VP6, within their particles. Bluetongue virus (BTV), an important livestock pathogen, is the prototype Orbivirus BTV VP6 is an ATP-dependent RNA helicase, and it is indispensable for virus replication. In the study described in this report, we investigated how VP6 might be recruited to the virus capsid and whether the BTV structural protein VP3, which forms the internal layer of the virus capsid core, is involved in VP6 recruitment. We first demonstrated that VP6 interacts with VP3 and colocalizes with VP3 during capsid assembly. A series of VP6 mutants was then generated, and in combination with immunoprecipitation and size exclusion chromatographic analyses, we demonstrated that VP6 directly interacts with VP3 via a specific region of the C-terminal portion of VP6. Finally, using our reverse genetics system, mutant VP6 proteins were introduced into the BTV genome and interactions between VP6 and VP3 were shown in a live cell system. We demonstrate that BTV strains possessing a mutant VP6 are replication deficient in wild-type BSR cells and fail to recruit the viral replicase complex into the virus particle core. Taken together, these data suggest that the interaction between VP3 and VP6 could be important in the packaging of the viral genome and early stages of particle formation.IMPORTANCE The orbivirus bluetongue virus (BTV) is the causative agent of bluetongue disease of livestock, often causing significant economic and agricultural impacts in the livestock industry. In the study described in this report, we identified the essential region and residues of the unique orbivirus capsid protein VP6 which are responsible for its interaction with other BTV proteins and its subsequent recruitment into the virus particle. The nature and mechanism of these interactions suggest that VP6 has a key role in packaging of the BTV genome into the virus particle. As such, this is a highly significant finding, as this new understanding of BTV assembly could be exploited to design novel vaccines and antivirals against bluetongue disease

Non-thermal cytocidal effect of infrared irradiation on cultured cancer cells using specialized device

The definitive version is available at www.blackwell-synergy.comAs infrared penetrates the skin, thermal effects of infrared irradiation on cancer cells have been investigated in the field of hyperthermia. We evaluated non-thermal effects of infrared irradiation using a specialized device (1100-18000 nm with filtering of wavelengths between 1400 and 1500 nm and contact cooling) on cancer cells. In in vitro study, five kinds of cultured cancer cell lines (MCF7 breast cancer, HeLa uterine cervical cancer, NUGC-4 gastric cancer, B16F0 melanoma, and MDA-MB435 melanoma) were irradiated using the infrared device, and then the cell proliferation activity was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Proliferation of all the cancer cell lines was significantly suppressed by infrared irradiation. Total infrared output appeared to be correlated with cell survival. Increased temperature during infrared irradiation appeared not to play a role in cell survival. The maximum temperature elevation in the wells after each shot in the 20 and 40 J/cm2 culture was 3.8 degrees C and 6.9 degrees C, respectively. In addition, we have shown that infrared irradiation significantly inhibited the tumor growth of MCF7 breast cancer transplanted in severe combined immunodeficiency mice and MDA-MB435 melanoma transplanted in nude mice in vivo. Significant differences between control and irradiated groups were observed in tumor volume and frequencies of TUNEL-positive and Ki-67-positive cells. These results indicate that infrared, independent of thermal energy, can induce cell killing of cancer cells. As this infrared irradiation schedule reduces discomfort and side effects, reaches the deep subcutaneous tissues, and facilitates repeated irradiations, it may have potential as an application for treating various forms of cancer.ArticleCANCER SCIENCE. 101(6):1396-1402 (2010)journal articl