349 research outputs found

    TAK1 mediates an activation signal from toll-like receptor(s) to nuclear factor-κB in lipopolysaccharide-stimulated macrophages

    Get PDF
    AbstractStimulation of monocytes/macrophages with lipopolysaccharide (LPS) results in activation of nuclear factor-κB (NF-κB), which plays crucial roles in regulating expression of many genes involved in the subsequent inflammatory responses. Here, we investigated roles of transforming growth factor-β activated kinase 1 (TGF-TAK1), a mitogen-activated protein kinase kinase kinase (MAPKKK), in the LPS-induced signaling cascade. A kinase-negative mutant of TAK1 inhibited the LPS-induced NF-κB activation both in a macrophage-like cell line, RAW 264.7, and in human embryonic kidney 293 cells expressing toll-like receptor 2 or 4. Furthermore, we demonstrated that endogenous TAK1 is phosphorylated upon simulation of RAW 264.7 cells with LPS. These results indicate that TAK1 functions as a critical mediator in the LPS-induced signaling pathway

    Correction of Apparent Viscoelasticity of Skin Surface

    Get PDF
    The body structures under the skin surface, such as bones and tendon, have an influence on the stiffness evaluation observed from the surface. In this case, the observed stiffness should be called an apparent stiffness. To obtain the biomechanical properties of skin itself, the influence of body structure should be removed. This study deals with the correction method of apparent viscoelasticity which calculated from apparent biomechanical impedance. This method is applied to the measured result of the forearm and the right chest to confirm its effectiveness

    Functional characterization of Ebola virus L-domains using VSV recombinants

    Get PDF
    AbstractVSV recombinants containing the overlapping L-domain sequences from Ebola virus VP40 (PTAPPEY) were recovered by reverse-genetics. Replication kinetics of M40-WT, M40-P24L, and M40-Y30A were indistinguishable from VSV-WT in BHK-21 cells, whereas the double mutant (M40-P2728A) was defective in budding. Insertion of the Ebola L-domain region into VSV M protein was sufficient to alter the dependence on host proteins for efficient budding. Indeed, M40 recombinants containing a functional PTAP motif specifically incorporated endogenous tsg101 into budding virions and were dependent on tsg101 expression for efficient budding. Thus, VSV represents an excellent negative-sense RNA virus model for elucidating the functional aspects and diverse host interactions associated with the L-domains of Ebola virus

    Portable system for measuring biomechanical properties

    Get PDF
    A portable system has been developed for measuring biomechanical impedance on the skin surface. The measurement system comprises a measuring probe and a measuring device. The probe is of the pen-type. The device includes a random noise source, amplifiers, an A/D converter, a microcomputer, a liquid crystal display and a floppy disk unit. The biomechanical impedances on the skin surface are measured and the skin viscoelasticity are obtained. SI (stiffness index) is proposed as the new index of skin stiffness. The coefficient of correlation between SI and palpation scores is 0.797</p

    Development of Interactive Learning Material for Internal Stress of a Bending Beam

    Get PDF
     材料力学は工学初心者にとって理解が容易な分野であるとは言い難い。例えば,中学校技術科教員を目指す学生で,片持ちはりに力を加えた場合にどのような内部応力が発生するのか正しく理解しているものは少ない。本研究では,仮想空間に呈示された片持ちはりに対して,学習者が三次元力覚呈示装置を介して接触し,自ら力を加えて変形させたときの内部応力分布を視覚的に確認できる教材を開発した。内部応力の算出には有限要素法の弾性二次元解析を用いた。自然な力覚呈示には1ms以下の周期が必要とされるが,有限要素法は要素数(節点数)とともに計算時間が増加する。本研究では要素数(節点数)と計算時間の関係を明らかにした上で,力覚呈示の条件を満たす仕様を決定した。結果として十分な分解能を持つ分割要素を組み込んだ教材においても,要求される計算速度を達成できることが確認された

    鶏精液の凍結保存に関する研究 : II. 凍結精液による後代検定

    Get PDF
     -79℃で3ヵ月間凍結保存した精液を用いて人工受精し, 得られた白レグ雄鶏の精液の一般性状を調べ,更にこの雄鶏を白レグ雌4羽に交配してその受精率,ふ化率,ふ化雛の性比および生時体重等を調べ,引きつづき雛の発育状態を観察した結果は次の如くである. 1. 凍結精液よりふ化した雄鶴のー射精時当りの平均射精量は0.13±0.06 ml. であった. 2. 精子濃度は1mm3 当り平均4.12±1.22百万でー射精当りの総精子数は0.543±0.310 十億であった. 3. 採取精液のpHは平均7. 18±0.19 であった. 4. 採取精液中の畸形精子の割合は平均11. 0±6.3% であった, 5. -79℃で3ヵ月間凍結保存した精液からふ化した雄鶏を白レグ雌4羽に交配した場合, 交配後2週間の平均受精率およびふ化率はそれぞれ78.8% ,53.9% であった. 6. 上述の交配試験の結果得られた雛14 羽の性比は8♂♂ : 6♀♀で雄鶏がやや多いように思われる. 7. ふ化雛の初生体重は平均43.03±1.82g で従来の白レグ雛の平均初生体重37.5 g 1亡くらべて約16%増重の雛が得られた. 8. 得られた雛はいずれも極めて活潑で,普通の卵からふ化した雛とくらべて何等異なるところがなく順調な発育をつづけている.The present experiments have examined the general properties of semen produced by the cock hatched from the deep-freezing semen stored for three months at -79°C. The cock was mated with four White Leghorn hens to examine the fertility, hatchability of the eggs produced by the hens. Further the abnormalities, sex ratio and growing conditions of chicks hatched from their fertilized eggs were studied in order to inquire into the progeny test. The results can be summarized as follows; 1. The amount of semen at one operation was 0.13 ± 0.06 ml average. 2. Semen concentration per 1 mm3 was 4.12 ± 1.22 millions average and the total number of spermatozoa per ejaculation was 0.543 ± 0.310 billions average. 3. pH-value of the semen was 7.18±0.19 on the average. 4. The percentages of abnormal spermatozoa in the semen was 11.0 ± 6.3 on the average. 5. The fertility and hatchability of the eggs produced by crossing between the cock hatched from the deep-freezing semen stored for three months at -79°C and the four White Leghorn hens were respectively 78.8 percent and 53.9 percent on the average during two weeks after mating. 6. Sex ratio in the present experiments showed 8 ♂♂ : 6 ♀♀, or emerged with 57.1 percent males among 14 chicks. Male seems to be slightly in evidence in the ratio of sexes. 7. Live weight of a-day-old chicks was 43.03 ± 1.82 g on the average and about 16 percent heavier than that of a normal one day old White Leghorn chick before. 8. The progenies gained by the present experiments showed a very active behavior and no abnormality compared to chicks hatched from normal nest eggs

    Interfacial Effects on the Spherulitic Morphology of Isotactic Polystyrene Thin Films on Liquid Substrates

    Get PDF
    The influence of interfaces on the morphology of flat spherulites of isotactic polystyrene (iPS) grown in thin films on liquid substrates was investigated. Amorphous iPS thin films spin-cast from a solution were annealed for cold crystallization on glycerol and silicone oil (nonsolvents for iPS). The number density of grown spherulites was revealed to be higher on the glycerol substrate than on the silicone oil substrate. This implies that the primary nucleation rate of crystallization is greater at the iPS/glycerol interface than at the iPS/silicone oil interface. The results may be consistent with the previous findings that concern the molecular interaction between atactic polystyrene and nonsolvents at the interface. In some cases, holes were formed in the thin films during the cold crystallization due to dewetting, which also significantly affect the spherulite morphology via, for example, transcrystallization

    Structural Transformation of Tungsten-Zirconium Hydroxide Crystals Upon Calcination Characterized by XRD, XAFS and Acid Catalyzed Reaction

    Get PDF
    W:Zr 比が2:1 の二元系水酸化物を水熱合成法にて調製し,水熱処理の保持時間および焼成温度の異なる物質の構造をX 線回折,X 線吸収分光法で検討し,酸触媒特性を評価した.453 K での水熱処理では12 時間までは高表面積かつ結晶性の低い化学種(I 相)が生じ,24 時間以降で結晶性の高い水和物(ZWOH 結晶)が得られた.ZWOH 結晶は573−773K で結晶性の低いZrW2O8 多形(II 相),823−873K で立方晶ZrW2O8 へ変化することをX 線分析,UV-Vis 分光法および熱重量分析で確認した.I 相はアニソールのベンジルアルコールによるアルキル化を促進する固体強酸触媒として機能し,873K 焼成体が最高活性を示した.ZWOH 結晶およびZrW2O8 はアルキル化活性を示さなかった.立方晶系ZrW2O8 の結晶性の低いI 相が混在しても通常のXRD 解析では検出困難であるが,表面積測定および活性試験を併用すると混在の推定が可能であった.Tungsten zirconium hydroxides (ZWOH) with the molar ratio of W/Zr =2 were synthesized by a hydrothermal process at 453 K for 6-72 h. Structure of the hydroxides with different crystallinity and the transformation upon calcination were characterized by XRD, XAFS, UV-vis spectroscopic techniques. The ill-crystallized ZWOH with large surface area (>100m2 ·g−1; phase-I) was formed via hydrothermal treatment till 12 h, and well crystallized ZrW2O7(OH)2(H2O)2 (< 2 m2 ·g−1; c-ZWOH) was formed after 24 h. W L-edge XAFS, optical bandgap and thermal gravity analyses gave direct evidence to support the previous suggestion about dehydration process of c-ZWOH to ZrW2O8, where ZrW2O8 polymorphism with low crystallinity (phase-II) and cubic ZrW2O8 crystal formed after calcination in the range of 573−773 and 823−873 K, respectively. The ZWOH phase-I was found to promote alkylation of benzylalcohol with anisole, and the activity exhibited the maximum after calcination at 873 K. The c-ZWOH and ZrW2O8 polymorphisms were catalytically inert for the reaction. Existence of active phase-I as a minor species in ZrW2O8 little influence on XRD pattern, but surface area measurements and the catalytic performance might help to evaluate fraction of phase-I in the Zr-W-O system. The ZWOH phase-I was candidate for a model catalyst of tungstated zirconia strong solid acid to investigate the acidity generation mechanism
    corecore