An All-Recombinant Protein-Based Culture System Specifically Identifies Hematopoietic Stem Cell Maintenance Factors.

Hematopoietic stem cells (HSCs) are considered one of the most promising therapeutic targets for the treatment of various blood disorders. However, due to difficulties in establishing stable maintenance and expansion of HSCs in vitro, their insufficient supply is a major constraint to transplantation studies. To solve these problems we have developed a fully defined, all-recombinant protein-based culture system. Through this system, we have identified hemopexin (HPX) and interleukin-1α as responsible for HSC maintenance in vitro. Subsequent molecular analysis revealed that HPX reduces intracellular reactive oxygen species levels within cultured HSCs. Furthermore, bone marrow immunostaining and 3D immunohistochemistry revealed that HPX is expressed in non-myelinating Schwann cells, known HSC niche constituents. These results highlight the utility of this fully defined all-recombinant protein-based culture system for reproducible in vitro HSC culture and its potential to contribute to the identification of factors responsible for in vitro maintenance, expansion, and differentiation of stem cell populations

Tumorigenesis of Epstein–Barr Virus-Positive Epithelial Cell Lines Derived from Gastric Tissues in the SCID Mouse

AbstractTo study the tumorigenesis of Epstein–Barr virus (EBV)-positive epithelial cell lines GT38 and GT39 derived from human gastric tissues, we inoculated these cells under the skin of severe combined immunodeficient (SCID) mice. The development of tumors was observed in each of the mice about 2 months after the inoculation. The tumors were diagnosed with undifferentiated carcinoma by hematoxylin/eosin staining. EBV-encoded small RNA1 was detected in the paraffin-embedded tumor sections. The tumor cells had human chromosome. The circular, but not linear, EBV DNA was detected in the tumors. The molecular sizes of EBV DNA termini were the same as that of the inoculated GT38 or GT39 cells. The expressions of EBV nuclear antigen 2 and latent membrane protein 1 reduced in the tumors. Transcripts of BamHI C and W promoters in latency III were detected in the tumors and the cultured cells in vitro. The tumor cells were passaged from one SCID mouse to other SCID mice and to cultures in vitro. This is the first evidence that the EBV-positive epithelial cell lines produced tumors in the SCID mouse

Development of the analog ASIC for multi-channel readout X-ray CCD camera

We report on the performance of an analog application-specific integrated circuit (ASIC) developed aiming for the front-end electronics of the X-ray CCDcamera system onboard the next X-ray astronomical satellite, ASTRO-H. It has four identical channels that simultaneously process the CCD signals. Distinctive capability of analog-to-digital conversion enables us to construct a CCD camera body that outputs only digital signals. As the result of the front-end electronics test, it works properly with low input noise of =<30 uV at the pixel rate below 100 kHz. The power consumption is sufficiently low of about 150 mW/chip. The input signal range of 720 mV covers the effective energy range of the typical X-ray photon counting CCD (up to 20 keV). The integrated non-linearity is 0.2% that is similar as those of the conventional CCDs in orbit. We also performed a radiation tolerance test against the total ionizing dose (TID) effect and the single event effect. The irradiation test using 60Co and proton beam showed that the ASIC has the sufficient tolerance against TID up to 200 krad, which absolutely exceeds the expected amount of dose during the period of operating in a low-inclination low-earth orbit. The irradiation of Fe ions with the fluence of 5.2x10^8 Ion/cm2 resulted in no single event latchup (SEL), although there were some possible single event upsets. The threshold against SEL is higher than 1.68 MeV cm^2/mg, which is sufficiently high enough that the SEL event should not be one of major causes of instrument downtime in orbit.Comment: 16 pages, 6 figure

グラス ファイバー デ ホキョウ サレタ コウキョウド コンポジット レジン オ モチイタ 3 ユニット ブリッジ チリョウ ニツイテ

Mechanical strength to withstand occlusal force is required to the crown restorations of molars. Ag-Pd-Au alloy has been used as the acceptable material of the National Health Insurance system in Japan. However, the metallic color of prosthesis does not meet the aesthetic requirements of the patients, and there is also a problem to the provider side of the treatment that the price fluctuation is large by soaring material costs. A fiber reinforced metal-less bridge is proposed to resolve these problems and we began clinical application of this prosthetic treatment from September, 2012 on the approval of Tokushima University Hospital ethics committee. So far, six patients have been treated with 8 fiber reinforced bridges, and this treatment in Tokushima University Hospital was approved in Shikoku Regional Bureau of Health and Welfare as the advanced medical. We have followed the treatment for a maximum of more than two years, and it has been passed successfully with patient's satisfaction. Slightly problems which were caused in the hybrid resin material, could be easily solved by the direct procedures. This clinical results in short term suggested that the fiber reinforced metalless bridge have a sufficiently high therapeutic effect as a prosthetic method

Regeneration of Graft Livers and Limited Contribution of Extrahepatic Cells After Partial Liver Transplantation in Humans

Background Liver regeneration is still not fully understood. Partial liver transplantation (LT) can provide the opportunity to investigate the mechanisms of liver regeneration, including the contribution of extrahepatic cells to liver regeneration. Methods Of 61 patients transplanted with partial liver graft between August 1997 and October 2006, 56 patients were studied, including 49 adults and 7 children. Sequential computed tomography volumetric analysis was performed for volume measurement, while proliferating cell nuclear antigen (PCNA) labeling index was investigated for liver cell proliferation in nonprotocol liver biopsy specimens. In addition, 15 male recipients who had female liver grafts were investigated in order to detect Y chromosomes as extrahepatic cells in nonprotocol liver biopsy specimens. Results Graft volume per standard liver volume was markedly increased after adult-to-adult living-donor (LD) LT. In pediatric transplants, there was no volume increase over time. PCNA labeling index was vigorous in adult-to-adult LDLT in the early period after LDLT. No Y chromosome was evident in hepatocytes from female-donor male-recipient grafts during or after liver regeneration. However, in the cases of failing grafts of this type, many Y-chromosome-positive cells were observed in the graft liver. The character of those cells was CD34(−), CK9(−), hepatocyte-specific antigen(−), and CD68(+/−). Conclusion In adult-to-adult LDLT, vigorous liver regeneration occurs in the graft liver, demonstrated by not only volumetric but cell kinetic analysis. Involvement of extrahepatic cells in normal liver regeneration seems limited

X-ray harmonic comb from relativistic electron spikes

X-ray devices are far superior to optical ones for providing nanometre spatial and attosecond temporal resolutions. Such resolution is indispensable in biology, medicine, physics, material sciences, and their applications. A bright ultrafast coherent X-ray source is highly desirable, for example, for the diffractive imaging of individual large molecules, viruses, or cells. Here we demonstrate experimentally a new compact X-ray source involving high-order harmonics produced by a relativistic-irradiance femtosecond laser in a gas target. In our first implementation using a 9 Terawatt laser, coherent soft X-rays are emitted with a comb-like spectrum reaching the 'water window' range. The generation mechanism is robust being based on phenomena inherent in relativistic laser plasmas: self-focusing, nonlinear wave generation accompanied by electron density singularities, and collective radiation by a compact electric charge. The formation of singularities (electron density spikes) is described by the elegant mathematical catastrophe theory, which explains sudden changes in various complex systems, from physics to social sciences. The new X-ray source has advantageous scalings, as the maximum harmonic order is proportional to the cube of the laser amplitude enhanced by relativistic self-focusing in plasma. This allows straightforward extension of the coherent X-ray generation to the keV and tens of keV spectral regions. The implemented X-ray source is remarkably easily accessible: the requirements for the laser can be met in a university-scale laboratory, the gas jet is a replenishable debris-free target, and the harmonics emanate directly from the gas jet without additional devices. Our results open the way to a compact coherent ultrashort brilliant X-ray source with single shot and high-repetition rate capabilities, suitable for numerous applications and diagnostics in many research fields

Diverse Effects of FK506 on the Apoptosis of Hepatocytes and Infiltrating Lymphocytes in an Allografted Rat Liver.

BACKGROUND: The current study investigated whether FK506 (FK) regulates the apoptotic systems in allografted rat liver and the contribution of Fas/Fas-ligand system and Bcl-2 family during acute rejection. MATERIALS AND METHODS: The recipients were divided into three groups, the allo, the allo-FK, and the syn group. Rats were euthanized 1, 3, 5, and 7 d after OLT. Apoptotic activity was explored using terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. The expression of Fas/Fas-ligand and Bcl-2/Bax in the grafted livers was investigated by Western blotting and immunohistochemistry. RESULTS: The apoptotic index (AI) of hepatocytes in the allo-FK group was less than that in the allo group. Fas in the allo group was more intense than that in the allo-FK group in the periportal areas on day 1 and 3, while Bcl-2 in the allo group was less intense than that in the allo-FK group in the pericaval areas at all time-points after OLT. CONCLUSION: FK provides beneficial antiapoptotic effects on hepatocytes in the grafted rat livers through both the down-regulation of Fas expression in the periportal areas and the up-regulation of Bcl-2 expression in the pericaval areas

The Migratory Ability of Gonadal Germ Cells in the Domestic Chicken

The migratory ability of germ cells collected from gonads at different stages of embryonic development was investigated in the domestic chicken. In Experiment 1, primordial germ cells (PGCs) were collected from 2.5-day-old embryo. Also gonadal germ cells (GGCs) were collected from 6.5-, 10.5-, 14.5-, 18.5-, and 20.5-day-old embryos. PGCs and GGCs were labeled with the fluorescent dye PKH-26, and 20 fluorescently labeled PGCs or GGCs were injected into the vascular systems of 2-day-old recipient embryos. The total number of fluorescently labeled cells recovered from both the left and right gonads of the recipient embryos was counted 5 days after injection. The proportion of recipient embryos carrying fluorescently labeled cells was 100% when the donor GGCs were collected from 6.5-, and 10.5-day-old embryos. The proportion decreased when the donor GGCs were from embryos incubated for longer than 14.5 days. An inverse relationship was observed between the total number of fluorescently labeled cells in the recipient gonads and the age of the donor embryo. In Experiment 2, gonadal cell suspensions were prepared from the left gonads of newborn chicks and adult chickens. Gonadal cell suspensions were labeled with the fluorescent dye PKH-26 and injected into the vascular systems of 2-day-old recipient embryos. The proportions of recipient embryos with fluorescently labeled cells in their gonads were 100% (3/3), 100% (3/3), 100% (3/3), and 67% (2/3) when the injected gonadal cell suspension was from male newborn chicks, female newborn chicks, adult roosters, and adult hens, respectively. These results indicate the presence of migratory germ cells in the gonads of developing embryos until day 20.5 of incubation. Furthermore, these results also suggest the presence of migratory cells even in the sexually matured testes or ovaries

Production of Inter-Genus Somatic Nuclear Transferred Gonadal Germ Cells (snt-GGCs) in Avian Species

Interspecies or even inter-genus somatic nuclear transfer is considered to be an effective means for conserving a wide variety of avian genetic resources. However, somatic nuclear transfer offspring production is currently limited to mammals. Therefore, the present experiment was designed in an attempt to produce inter-genus somatic nuclear transferred gonadal germ cells (snt-GGCs) between chicken and quail. Electrofusion was carried out between embryonic blood cells (EBCs) collected from 4-day-old embryos (donor cells) and gonadal germ cells (GGCs) from 7-day-old chick embryos or 6-day-old quail embryos (recipient cells). GGCs were labeled with PKH26 fluorescent dye as a marker. Electrofusion was carried out according to previously described methods. The combinations of donor-recipient cells were designed to contain all four possible combinations: E(c)-G(c), E(q)-G(q), E(q)-G(c) and E(c)-G(q), where E, G, c and q are abbreviations for EBCs, GGCs, chick and quail, respectively. Following electrofusion, the fusion solution containing cells were stained with 1&mu;g/mL Hoechst 33342. PKH26-labeled cells with two or more nuclei of different sizes were determined to be snt-GGCs. The experiment was replicated ten times and snt-GGCs were observed in five (50%), three (30%), four (40%) and five (50%) replicates. The average number of snt-GGCs produced per replicate were 0.6 (1.2%), 0.3 (0.6%), 0.5 (1.0%) and 0.5 (1.0%) for E(c)-G(c), E(q)-G(q), E(q)-G(c) and E(c)-G(q), respectively. The present results demonstrate that inter-genus snt-GGCs can be produced by electrofusion using EBCs and GGCs in avian species