Katsuaki Sato - Academia.edu (original) (raw)
Papers by Katsuaki Sato
Arerugī = [Allergy], 2016
Immunology letters, Jan 30, 2016
We have previously demonstrated that administration of oligomannose-coated liposomes (OMLs), in w... more We have previously demonstrated that administration of oligomannose-coated liposomes (OMLs), in which an antigen is encased, induce antigen-specific Th1 immune responses and CTLs. In the present study, we showed that TLR4 signaling is required for the induction of specific immune responses following OML administration. In C3H/HeJ mice, which express a dysfunctional TLR4, the antigen-specific Th1 immune response could not be elicited following intraperitoneal administration of OVA-encased OMLs (OML/OVA). However, OML uptake by peritoneal cells, the subsequent production of IL-12 and the upregulation of co-stimulatory molecules and MHC class II on the cells in response to OML uptake occurred in C3H/HeJ mice to the same extent as in wild type C3H/HeN mice. In addition, peritoneal phagocytic cells from TLR4(-/-) mice that ingest OML/OVA can activate CD4(+) T cells from OT-II mice. On the other hand, the number of OML-ingesting peritoneal cells that migrated into mesenteric lymph nodes i...
Japanese Journal of Applied Physics, 1995
A bright green photoluminescence with a peak at 540 nm was observed at low temperature in the α-p... more A bright green photoluminescence with a peak at 540 nm was observed at low temperature in the α-phase ZnAl2S4 ternary compound grown by heating ZnS, Al and S powders. The emission is interpreted as arising from donor-acceptor(DA)-pair recombination. At room temperature the green emission is dominated by two weak emission bands in the infrared spectral region.
J Phys Soc Jpn, 1982
Reflectance magneto-circular dichroism spectra and Kerr rotation spectra have been measured for t... more Reflectance magneto-circular dichroism spectra and Kerr rotation spectra have been measured for the first time on a pyrite type ferromagnet CoS2, for photon energies between 0.5 and 3.5 eV below the Curie temperature. There have been observed three major structures around 0.8, 1.5 and 2.8 eV, among which the most prominent is the one at 0.8 eV; the Kerr rotation reaches the value of 1.1° at the peak. Real and imaginary parts of the off-diagonal element of the dielectric tensor have been calculated from the observed spectra. Theoretical study has revealed that the line shape of the 0.8 eV structure can be explained in terms of the localized many-electron excitation associated with the d\varepsilon-dγ absorption edge of this compound. This corresponds to the narrow-band nature of the pyrite type compound.
Scientific Reports, 2016
Endosomal toll-like receptor (TLR)-mediated detection of viral nucleic acids (NAs) and production... more Endosomal toll-like receptor (TLR)-mediated detection of viral nucleic acids (NAs) and production of type I interferon (IFN-I) are key elements of antiviral defense, while inappropriate recognition of self NAs with the induction of IFN-I responses is linked to autoimmunity such as psoriasis and systemic lupus erythematosus. Plasmacytoid dendritic cells (pDCs) are cells specialized in robust IFN-I secretion by the engagement of endosomal TLRs, and predominantly express sialic acid-binding Ig-like lectin (Siglec)-H. However, how pDCs control endosomal TLR-mediated immune responses that cause autoimmunity remains unclear. Here we show a critical role of pDCs in TLR7-mediated autoimmunity using gene-modified mice with impaired expression of Siglec-H and selective ablation of pDCs. pDCs were shown to be indispensable for the induction of systemic inflammation and effector T-cell responses triggered by TLR7 ligand. pDCs aggravated psoriasiform dermatitis mediated through the hyperproliferation of keratinocytes and enhanced dermal infiltration of granulocytes and γδ T cells. Furthermore, pDCs promoted the production of anti-self NA antibodies and glomerulonephritis in lupus-like disease by activating inflammatory monocytes. On the other hand, Siglec-H regulated the TLR7-mediated activation of pDCs. Thus, our findings reveal that pDCs provide an essential link between TLR7-mediated innate and adaptive immunity for the initiation of IFN-I-associated autoimmune inflammation.
Japanese Journal of Applied Physics, 1995
Japanese Journal of Applied Physics, 1992
Optical absorption and electron spin resonance (ESR) spectra have been studied in as-grown, Cr-do... more Optical absorption and electron spin resonance (ESR) spectra have been studied in as-grown, Cr-doped, and annealed in different atmospheres CuAlS2 crystals. It has been found that the major influence on the optical and ESR properties of CuAlS2 crystals, obtained by chemical vapour transport, arises from the transition ions Fe3+ and Cr2+, which are present in the crystal lattice as residual impurities. Thermal treated crystals exhibit drastic changes in their absorption and ESR spectra depending on the annealing atmosphere, which is explained by the process of the Fermi level motion in the vicinity of the Fe2+/Fe3+ and Cr+/Cr2+ demarcation levels. The results obtained show that the valence states of Fe and Cr ions and their relative amounts in each valence state are controlled by the position of the Fermi level in the band gap of the host crystal, and are stoichiometry on dependent.
Transactions of the Magnetics Society of Japan, Oct 1, 2002
The Journal of Urology, Apr 1, 1991
Seminal emission after transection of canine bilateral hypogastric nerves was investigated. Stimu... more Seminal emission after transection of canine bilateral hypogastric nerves was investigated. Stimulation of severed hypogastric nerves caused full volume seminal emission (greater than four drops) in all six dogs examined. In contrast, stimulation of sympathetic trunks of other six dogs at the level of caudal mesenteric artery caused no emission in three dogs and a limited volume of seminal emission (less than one drop) by pressing the ampulla in the remaining. When hypogastric nerves were transected one month prior to the experiment, however, stimulation of sympathetic trunks in the same manner caused full volume of seminal emission in all six dogs. Distal dissection of sympathetic trunks demonstrated nerve fibers to the seminal tract via the pelvic splanchnic nerves. The results indicate that the seminal tract receives at least two sympathetic pathways; one from hypogastric nerves and the other from lumbosacral sympathetic trunks, and that the latter compensatorily generates seminal emission after hypogastric nerve transection.
J Phys Soc Jpn, 1980
Optical reflectivity spectra have been measured at room temperature on a single crystal of CuFeS2... more Optical reflectivity spectra have been measured at room temperature on a single crystal of CuFeS2 between 0.025 and 6 eV. The experimental results have been used to calculate the optical constants, the dielectric constant and the absorption coefficient. There have been found an absorption band with peaks at 1.0 and 2.1 eV and an absorption edge at approximately 3.2 eV. The band can be assigned to the charge-transfer transition from the valence band to the empty 3d states of Fe, and the edge can be attributed to the commencement of the band to band transition. A schematical energy level diagram for CuFeS2 is given from the result.
Japanese Journal of Applied Physics, 1989
We measured subgap optical absorption and photoluminescence spectra in boron-doped a-Si:H films p... more We measured subgap optical absorption and photoluminescence spectra in boron-doped a-Si:H films prepared by photochemical vapor deposition (photo-CVD) techniques. We estimated the Urbach energy (E0) and the density of defect states (Ns) from the subgap optical absorption spectra; the value of Ns was estimated from PL spectra. We conclude that Ns is approximately proportional to a square root of the boron doping level (B2H6/SiH4) and that E0 increases linearly with an increase in the doping level. It is found that the doping mechanism proposed by Street applies to the photo-CVD films.
Physica Status Solidi, 2009
Japanese Journal of Applied Physics, Apr 1, 2007
A streak-camera system for the observation of high-speed crystallization processes induced by las... more A streak-camera system for the observation of high-speed crystallization processes induced by laser irradiation in phase-change (PC) recording materials has been developed. A distinct difference in the time-sequential development of the crystallized region was observed in two different types of PC materials, i.e., Sb78Te22 (eutectic composition) and Ge2Sb2Te5 (pseudobinary alloy) films. Taking into account a thermal simulation analysis, the observed difference is interpreted in terms of the different crystallization process. It is concluded that Sb78Te22, which is a growth-dominant film, is suitable for high-speed high-density recording.
日本応用磁気学会学術講演概要集 Digest of Annual Conference on Magnetics in Japan, Sep 1, 2002
Arerugī = [Allergy], 2016
Immunology letters, Jan 30, 2016
We have previously demonstrated that administration of oligomannose-coated liposomes (OMLs), in w... more We have previously demonstrated that administration of oligomannose-coated liposomes (OMLs), in which an antigen is encased, induce antigen-specific Th1 immune responses and CTLs. In the present study, we showed that TLR4 signaling is required for the induction of specific immune responses following OML administration. In C3H/HeJ mice, which express a dysfunctional TLR4, the antigen-specific Th1 immune response could not be elicited following intraperitoneal administration of OVA-encased OMLs (OML/OVA). However, OML uptake by peritoneal cells, the subsequent production of IL-12 and the upregulation of co-stimulatory molecules and MHC class II on the cells in response to OML uptake occurred in C3H/HeJ mice to the same extent as in wild type C3H/HeN mice. In addition, peritoneal phagocytic cells from TLR4(-/-) mice that ingest OML/OVA can activate CD4(+) T cells from OT-II mice. On the other hand, the number of OML-ingesting peritoneal cells that migrated into mesenteric lymph nodes i...
Japanese Journal of Applied Physics, 1995
A bright green photoluminescence with a peak at 540 nm was observed at low temperature in the α-p... more A bright green photoluminescence with a peak at 540 nm was observed at low temperature in the α-phase ZnAl2S4 ternary compound grown by heating ZnS, Al and S powders. The emission is interpreted as arising from donor-acceptor(DA)-pair recombination. At room temperature the green emission is dominated by two weak emission bands in the infrared spectral region.
J Phys Soc Jpn, 1982
Reflectance magneto-circular dichroism spectra and Kerr rotation spectra have been measured for t... more Reflectance magneto-circular dichroism spectra and Kerr rotation spectra have been measured for the first time on a pyrite type ferromagnet CoS2, for photon energies between 0.5 and 3.5 eV below the Curie temperature. There have been observed three major structures around 0.8, 1.5 and 2.8 eV, among which the most prominent is the one at 0.8 eV; the Kerr rotation reaches the value of 1.1° at the peak. Real and imaginary parts of the off-diagonal element of the dielectric tensor have been calculated from the observed spectra. Theoretical study has revealed that the line shape of the 0.8 eV structure can be explained in terms of the localized many-electron excitation associated with the d\varepsilon-dγ absorption edge of this compound. This corresponds to the narrow-band nature of the pyrite type compound.
Scientific Reports, 2016
Endosomal toll-like receptor (TLR)-mediated detection of viral nucleic acids (NAs) and production... more Endosomal toll-like receptor (TLR)-mediated detection of viral nucleic acids (NAs) and production of type I interferon (IFN-I) are key elements of antiviral defense, while inappropriate recognition of self NAs with the induction of IFN-I responses is linked to autoimmunity such as psoriasis and systemic lupus erythematosus. Plasmacytoid dendritic cells (pDCs) are cells specialized in robust IFN-I secretion by the engagement of endosomal TLRs, and predominantly express sialic acid-binding Ig-like lectin (Siglec)-H. However, how pDCs control endosomal TLR-mediated immune responses that cause autoimmunity remains unclear. Here we show a critical role of pDCs in TLR7-mediated autoimmunity using gene-modified mice with impaired expression of Siglec-H and selective ablation of pDCs. pDCs were shown to be indispensable for the induction of systemic inflammation and effector T-cell responses triggered by TLR7 ligand. pDCs aggravated psoriasiform dermatitis mediated through the hyperproliferation of keratinocytes and enhanced dermal infiltration of granulocytes and γδ T cells. Furthermore, pDCs promoted the production of anti-self NA antibodies and glomerulonephritis in lupus-like disease by activating inflammatory monocytes. On the other hand, Siglec-H regulated the TLR7-mediated activation of pDCs. Thus, our findings reveal that pDCs provide an essential link between TLR7-mediated innate and adaptive immunity for the initiation of IFN-I-associated autoimmune inflammation.
Japanese Journal of Applied Physics, 1995
Japanese Journal of Applied Physics, 1992
Optical absorption and electron spin resonance (ESR) spectra have been studied in as-grown, Cr-do... more Optical absorption and electron spin resonance (ESR) spectra have been studied in as-grown, Cr-doped, and annealed in different atmospheres CuAlS2 crystals. It has been found that the major influence on the optical and ESR properties of CuAlS2 crystals, obtained by chemical vapour transport, arises from the transition ions Fe3+ and Cr2+, which are present in the crystal lattice as residual impurities. Thermal treated crystals exhibit drastic changes in their absorption and ESR spectra depending on the annealing atmosphere, which is explained by the process of the Fermi level motion in the vicinity of the Fe2+/Fe3+ and Cr+/Cr2+ demarcation levels. The results obtained show that the valence states of Fe and Cr ions and their relative amounts in each valence state are controlled by the position of the Fermi level in the band gap of the host crystal, and are stoichiometry on dependent.
Transactions of the Magnetics Society of Japan, Oct 1, 2002
The Journal of Urology, Apr 1, 1991
Seminal emission after transection of canine bilateral hypogastric nerves was investigated. Stimu... more Seminal emission after transection of canine bilateral hypogastric nerves was investigated. Stimulation of severed hypogastric nerves caused full volume seminal emission (greater than four drops) in all six dogs examined. In contrast, stimulation of sympathetic trunks of other six dogs at the level of caudal mesenteric artery caused no emission in three dogs and a limited volume of seminal emission (less than one drop) by pressing the ampulla in the remaining. When hypogastric nerves were transected one month prior to the experiment, however, stimulation of sympathetic trunks in the same manner caused full volume of seminal emission in all six dogs. Distal dissection of sympathetic trunks demonstrated nerve fibers to the seminal tract via the pelvic splanchnic nerves. The results indicate that the seminal tract receives at least two sympathetic pathways; one from hypogastric nerves and the other from lumbosacral sympathetic trunks, and that the latter compensatorily generates seminal emission after hypogastric nerve transection.
J Phys Soc Jpn, 1980
Optical reflectivity spectra have been measured at room temperature on a single crystal of CuFeS2... more Optical reflectivity spectra have been measured at room temperature on a single crystal of CuFeS2 between 0.025 and 6 eV. The experimental results have been used to calculate the optical constants, the dielectric constant and the absorption coefficient. There have been found an absorption band with peaks at 1.0 and 2.1 eV and an absorption edge at approximately 3.2 eV. The band can be assigned to the charge-transfer transition from the valence band to the empty 3d states of Fe, and the edge can be attributed to the commencement of the band to band transition. A schematical energy level diagram for CuFeS2 is given from the result.
Japanese Journal of Applied Physics, 1989
We measured subgap optical absorption and photoluminescence spectra in boron-doped a-Si:H films p... more We measured subgap optical absorption and photoluminescence spectra in boron-doped a-Si:H films prepared by photochemical vapor deposition (photo-CVD) techniques. We estimated the Urbach energy (E0) and the density of defect states (Ns) from the subgap optical absorption spectra; the value of Ns was estimated from PL spectra. We conclude that Ns is approximately proportional to a square root of the boron doping level (B2H6/SiH4) and that E0 increases linearly with an increase in the doping level. It is found that the doping mechanism proposed by Street applies to the photo-CVD films.
Physica Status Solidi, 2009
Japanese Journal of Applied Physics, Apr 1, 2007
A streak-camera system for the observation of high-speed crystallization processes induced by las... more A streak-camera system for the observation of high-speed crystallization processes induced by laser irradiation in phase-change (PC) recording materials has been developed. A distinct difference in the time-sequential development of the crystallized region was observed in two different types of PC materials, i.e., Sb78Te22 (eutectic composition) and Ge2Sb2Te5 (pseudobinary alloy) films. Taking into account a thermal simulation analysis, the observed difference is interpreted in terms of the different crystallization process. It is concluded that Sb78Te22, which is a growth-dominant film, is suitable for high-speed high-density recording.
日本応用磁気学会学術講演概要集 Digest of Annual Conference on Magnetics in Japan, Sep 1, 2002