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31.
Akiharu Kubo Aiko Shiohama Takashi Sasaki Kazuhiko Nakabayashi Hiroshi Kawasaki Toru Atsugi Showbu Sato Atsushi Shimizu Shuji Mikami Hideaki Tanizaki Masaki Uchiyama Tatsuo Maeda Taisuke Ito Jun-ichi Sakabe Toshio Heike Torayuki Okuyama Rika Kosaki Kenjiro Kosaki Jun Kudoh Kenichiro Hata Akihiro Umezawa Yoshiki Tokura Akira Ishiko Hironori Niizeki Kenji Kabashima Yoshihiko Mitsuhashi Masayuki Amagai 《American journal of human genetics》2013,93(5):945-956
“Nagashima-type” palmoplantar keratosis (NPPK) is an autosomal recessive nonsyndromic diffuse palmoplantar keratosis characterized by well-demarcated diffuse hyperkeratosis with redness, expanding on to the dorsal surfaces of the palms and feet and the Achilles tendon area. Hyperkeratosis in NPPK is mild and nonprogressive, differentiating NPPK clinically from Mal de Meleda. We performed whole-exome and/or Sanger sequencing analyses of 13 unrelated NPPK individuals and identified biallelic putative loss-of-function mutations in SERPINB7, which encodes a cytoplasmic member of the serine protease inhibitor superfamily. We identified a major causative mutation of c.796C>T (p.Arg266∗) as a founder mutation in Japanese and Chinese populations. SERPINB7 was specifically present in the cytoplasm of the stratum granulosum and the stratum corneum (SC) of the epidermis. All of the identified mutants are predicted to cause premature termination upstream of the reactive site, which inhibits the proteases, suggesting a complete loss of the protease inhibitory activity of SERPINB7 in NPPK skin. On exposure of NPPK lesional skin to water, we observed a whitish spongy change in the SC, suggesting enhanced water permeation into the SC due to overactivation of proteases and a resultant loss of integrity of the SC structure. These findings provide an important framework for developing pathogenesis-based therapies for NPPK. 相似文献
32.
33.
Hideyuki Furukawa Hideki Matsuo Takashi Deguchi Akio Shiga Hirotoshi Samejima 《Bioscience, biotechnology, and biochemistry》2013,77(5):617-623
l-Lysine monohydrochloride and d-glucose were allowed to react in a bicarbonate buffer of pH 8.8 under refluxing. The reaction mixture was then chromatographed on a thin-layer plate of Kiesel Gel using n-propanol ethyl-acetate water 25% aqueous ammonia (6: 1: 2: 1 v/v) as a developing agent. Elson-Morgan-reactive spots on the chromatogram were eluted individually, and each of the eluates was incubated with L. bifidus var. pennsylvanicus in a defined medium. A certain fraction on the chromatogram showed remarkably promoting effect on both the acid productivity and the growth of the organism. And such effect of the fraction was much stronger than that of N-acetyl-d-glucosamine which had been known as a “Bifidus Factor” 相似文献
34.
Yuji Shimizu Mio Nakazato Takaharu Sekita Koichiro Kadota Kazuhiko Arima Hironori Yamasaki Hisashi Goto Satoshi Shirahama Noboru Takamura Kiyoshi Aoyagi Takahiro Maeda 《Journal of physiological anthropology》2013,32(1):19
Background
Previous studies have reported an inverse association between height and risk of cardiovascular disease. However, evidence is limited for the association between risk of atherosclerosis and height. Further, although the association between atherosclerosis and body mass index (BMI) is reportedly positive, there have been no reports of studies on associations between height and atherosclerosis in relation to BMI.Methods
We conducted a cross-sectional study of Japanese men aged 30 to 89 years undergoing general health check-ups.Results
Of the 1,337 men, 312 were diagnosed with carotid atherosclerosis (carotid intima-media thickness (CIMT) ≥ 1.1 mm), but no significant association was found between height and carotid atherosclerosis for the entire study group. Stratification by BMI status of those analytical findings disclosed a significant inverse association between height and carotid atherosclerosis among overweight (BMI ≥ 25 kg/m2) but not among non-overweight (BMI < 25 kg/m2) men. The classical cardiovascular risk factors-adjusted odds ratio (OR) and 95% confidence interval (CI) of carotid atherosclerosis for an increment of one SD (standard deviation) in height (6.70 cm) were 0.71 (0.54 to 0.94) for overweight (BMI ≥ 25 kg/m2) and 1.05 (0.87 to 1.27) for non-overweight (BMI < 25 kg/m2) men.Conclusion
Independent from classical cardiovascular risk factors, height was found to be inversely associated with carotid atherosclerosis for overweight but not for non-overweight men. 相似文献35.
Mohammed Abdel-Wahab Masahiro Miyashita Atsushi Kitanaka Hironori Juichi Moustafa Sarhan Maged Fouda 《Bioscience, biotechnology, and biochemistry》2016,80(10):1879-1882
Over 200 components with molecular mass ranging mainly from 400 to 4000 Da were characterized from the venom of the vermivorous cone snail Conus fulgetrum that inhabit Egyptian Red Sea. One major component having a molecular mass of 2946 Da was purified by HPLC, and its primary structure was determined by a combination of Edman degradation and MS/MS analysis. 相似文献
36.
Deguchi R 《Developmental biology》2007,304(2):652-663
Mature limpet oocytes arrested at the first metaphase (MI) of meiosis are activated by the stimulation of fertilizing sperm. The aim of the present study was to clarify the spatiotemporal property and mechanism of intracellular Ca2+ increase in limpet oocytes, which is a prerequisite signal for initiation of development at fertilization. In all of the five limpet species tested, the initial Ca2+ rising phase just after fertilization took the form of a centripetal Ca2+ wave spreading from the whole cortex to the center (cortical flash), yielding a homogeneous Ca2+ elevation throughout the oocyte. The Ca2+ level remained high during the subsequent plateau phase lasting for several minutes and then returned nearly to the original value. No additional Ca2+ increase followed the plateau phase at least by the time of first cleavage. Both rising and plateau phases of Ca2+ increase at fertilization were inhibited by removal of external Ca2+, suggesting that continuous Ca2+ entry occurs throughout the Ca2+ increase. Injection of inositol 1,4,5-trisphosphate (IP3) was effective in generating a Ca2+ increase in mature limpet oocytes arrested at MI; however, their ability to show an IP3-induced Ca2+ increase was extremely low, as compared with other animals. Responsiveness to IP3 injection in immature oocytes arrested at the first prophase (PI) was similar to that in the mature oocytes, suggesting that the IP3-induced Ca2+ release system does not develop during the process of meiotic maturation in limpet oocytes. Caffeine, cyclic adenosine diphosphate ribose (cADPR), and nicotinic acid adenine dinucleotide phosphate (NAADP), the agents known to stimulate internal Ca2+ release mechanisms distinct from an IP3-dependent pathway, had no effect on intracellular Ca2+ changes in mature limpet oocytes. Labeling of the endoplasmic reticulum (ER) with DiI revealed that cortical ER clusters are only present in the localized region around meiotic chromosomes in mature oocytes. These data strongly suggest that Ca2+ release and its propagating mechanisms are undeveloped in limpet oocytes and that Ca2+ influx is the only Ca2+-mobilizing system available and functioning at fertilization. 相似文献
37.
Tatsuya Nagano Hironori Edamatsu Kazuyuki Kobayashi Nobuyuki Takenaka Masatsugu Yamamoto Naoto Sasaki Yoshihiro Nishimura Tohru Kataoka 《PloS one》2014,9(9)
Background
Phospholipase Cε (PLCε) is an effector of Ras and Rap small GTPases and expressed in non-immune cells. It is well established that PLCε plays an important role in skin inflammation, such as that elicited by phorbol ester painting or ultraviolet irradiation and contact dermatitis that is mediated by T helper (Th) 1 cells, through upregulating inflammatory cytokine production by keratinocytes and dermal fibroblasts. However, little is known about whether PLCε is involved in regulation of inflammation in the respiratory system, such as Th2-cells-mediated allergic asthma.Methods
We prepared a mouse model of allergic asthma using PLCε +/+ mice and PLCε ΔX/ΔX mutant mice in which PLCε was catalytically-inactive. Mice with different PLCε genotypes were immunized with ovalbumin (OVA) followed by the challenge with an OVA-containing aerosol to induce asthmatic response, which was assessed by analyzing airway hyper-responsiveness, bronchoalveolar lavage fluids, inflammatory cytokine levels, and OVA-specific immunoglobulin (Ig) levels. Effects of PLCε genotype on cytokine production were also examined with primary-cultured bronchial epithelial cells.Results
After OVA challenge, the OVA-immunized PLCε ΔX/ΔX mice exhibited substantially attenuated airway hyper-responsiveness and broncial inflammation, which were accompanied by reduced Th2 cytokine content in the bronchoalveolar lavage fluids. In contrast, the serum levels of OVA-specific IgGs and IgE were not affected by the PLCε genotype, suggesting that sensitization was PLCε-independent. In the challenged mice, PLCε deficiency reduced proinflammatory cytokine production in the bronchial epithelial cells. Primary-cultured bronchial epithelial cells prepared from PLCε ΔX/ΔX mice showed attenuated pro-inflammatory cytokine production when stimulated with tumor necrosis factor-α, suggesting that reduced cytokine production in PLCε ΔX/ΔX mice was due to cell-autonomous effect of PLCε deficiency.Conclusions
PLCε plays an important role in the pathogenesis of bronchial asthma through upregulating inflammatory cytokine production by the bronchial epithelial cells. 相似文献38.
39.
Keiji Uchiyama Hironori Miyata Masashi Yano Yoshitaka Yamaguchi Morikazu Imamura Naomi Muramatsu Nandita Rani Das Junji Chida Hideyuki Hara Suehiro Sakaguchi 《PloS one》2014,9(10)
Prion infection induces conformational conversion of the normal prion protein PrPC, into the pathogenic isoform PrPSc, in prion diseases. It has been shown that PrP-knockout (Prnp0/0) mice transgenically reconstituted with a mouse-hamster chimeric PrP lacking N-terminal residues 23-88, or Tg(MHM2Δ23-88)/Prnp0/0 mice, neither developed the disease nor accumulated MHM2ScΔ23-88 in their brains after inoculation with RML prions. In contrast, RML-inoculated Tg(MHM2Δ23-88)/Prnp0/+ mice developed the disease with abundant accumulation of MHM2ScΔ23-88 in their brains. These results indicate that MHM2Δ23-88 itself might either lose or greatly reduce the converting capacity to MHM2ScΔ23-88, and that the co-expressing wild-type PrPC can stimulate the conversion of MHM2Δ23-88 to MHM2ScΔ23-88 in trans. In the present study, we confirmed that Tg(MHM2Δ23-88)/Prnp0/0 mice remained resistant to RML prions for up to 730 days after inoculation. However, we found that Tg(MHM2Δ23-88)/Prnp0/0 mice were susceptible to 22L prions, developing the disease with prolonged incubation times and accumulating MHM2ScΔ23-88 in their brains. We also found accelerated conversion of MHM2Δ23-88 into MHM2ScΔ23-88 in the brains of RML- and 22L-inoculated Tg(MHM2Δ23-88)/Prnp0/+ mice. However, wild-type PrPSc accumulated less in the brains of these inoculated Tg(MHM2Δ23-88)/Prnp0/+ mice, compared with RML- and 22L-inoculated Prnp0/+ mice. These results show that MHM2Δ23-88 itself can convert into MHM2ScΔ23-88 without the help of the trans-acting PrPC, and that, irrespective of prion strains inoculated, the co-expressing wild-type PrPC stimulates the conversion of MHM2Δ23-88 into MHM2ScΔ23-88, but to the contrary, the co-expressing MHM2Δ23-88 disturbs the conversion of wild-type PrPC into PrPSc. 相似文献
40.
NAC transcription factors in plant abiotic stress responses 总被引:7,自引:0,他引:7
Nakashima K Takasaki H Mizoi J Shinozaki K Yamaguchi-Shinozaki K 《Biochimica et biophysica acta》2012,1819(2):97-103