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1.
Shinsaku Tokuda Young Hak Kim Hisako Matsumoto Shigeo Muro Toyohiro Hirai Michiaki Mishima Mikio Furuse 《PloS one》2015,10(12)
The relationship between chronic inflammation and cancer is well known. The inflammation increases the permeability of blood vessels and consequently elevates pressure in the interstitial tissues. However, there have been only a few reports on the effects of hydrostatic pressure on cultured cells, and the relationship between elevated hydrostatic pressure and cell properties related to malignant tumors is less well understood. Therefore, we investigated the effects of hydrostatic pressure on the cultured epithelial cells seeded on permeable filters. Surprisingly, hydrostatic pressure from basal to apical side induced epithelial stratification in Madin-Darby canine kidney (MDCK) I and Caco-2 cells, and cavities with microvilli and tight junctions around their surfaces were formed within the multi-layered epithelia. The hydrostatic pressure gradient also promoted cell proliferation, suppressed cell apoptosis, and increased transepithelial ion permeability. The inhibition of protein kinase A (PKA) promoted epithelial stratification by the hydrostatic pressure whereas the activation of PKA led to suppressed epithelial stratification. These results indicate the role of the hydrostatic pressure gradient in the regulation of various epithelial cell functions. The findings in this study may provide clues for the development of a novel strategy for the treatment of the carcinoma. 相似文献
2.
Pacemaker Potentials for the Periodic Burst Discharge in the Heart Ganglion of a Stomatopod, Squilla oratoria 总被引:4,自引:4,他引:0
From somata of the pacemaker neurons in the Squilla heart ganglion, pacemaker potentials for the spontaneous periodic burst discharge are recorded with intracellular electrodes. The electrical activity is composed of slow potentials and superimposed spikes, and is divided into four types, which are: (a) "mammalian heart" type, (b) "slow generator" type, (c) "slow grower" type, and (d) "slow deficient" type. Since axons which are far from the somata do not produce slow potentials, the soma and dendrites must be where the slow potentials are generated. Hyperpolarization impedes generation of the slow potential, showing that it is an electrically excitable response. Membrane impedance increases on depolarization. Brief hyperpolarizing current can abolish the plateau but brief tetanic inhibitory fiber stimulation is more effective for the abolition. A single stimulus to the axon evokes the slow potential when the stimulus is applied some time after a previous burst. Repetitive stimuli to the axon are more effective in eliciting the slow potential, but the depolarization is not maintained on continuous stimulation. Synchronization of the slow potential among neurons is achieved by: (a) the electrotonic connections, with periodic change in resistance of the soma membrane, (b) active spread of the slow potential, and (c) synchronization through spikes. 相似文献
3.
Takao Takahashi Toshiharu Yagi Toyohiro Oda Irvin E. Liener 《Bioscience, biotechnology, and biochemistry》2013,77(4):865-867
(+)-Biotin was synthesized from D-glucosamine in a sequence of 13 reactions. 相似文献
4.
The phosphorylation of the branched cyclodextrins, mono-6-O-(alpha-D-glucopyranosyl)cyclomaltohexaose, mono-6-O-(alpha-D-maltosyl)cyclomaltohexaose, mono-6-O-(alpha-D-glucopyranosyl)cyclomaltoheptaose, and mono-6-O-(alpha-D-maltosyl)cyclomaltoheptaose, in aqueous solution by sodium cyclo-mono-mu-imidotriphosphate (cMITP) was examined. In these reactions, only the 2-OH group of a single alpha-D-glucopyranosyl residue of the cyclodextrin ring was phosphorylated, in a maximum yield of 67%. A possible mechanism for the phosphorylation is discussed. 相似文献
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6.
Ito Y Okinaka Y Mori K Sugaya T Nishioka T Oka M Nakai T 《Diseases of aquatic organisms》2008,79(3):199-205
Betanodaviruses, the causative agents of viral nervous necrosis in marine fish, have bipartite positive-sense RNA genomes. The viruses have been classified into 4 distinct types based on nucleotide sequence similarities in the variable region (the so-called T4 region) of the smaller genomic segment RNA2 (1.4 kb). Betanodaviruses have marked host specificity, although the primary structures of the viral RNAs and encoded proteins are similar among the viruses. We have previously demonstrated, using reassortants between striped jack nervous necrosis virus (SJNNV) and redspotted grouper nervous necrosis virus (RGNNV), that RNA2, which encodes the coat protein, strictly controls host specificity. However, because RNA2 is large, we were unable to propose a mechanism underlying this RNA2-based host specificity. To identify the RNA2 region that controls host specificity, we constructed RNA2 chimeric viruses from SJNNV and RGNNV and tested their infectivity in the original host fish, striped jack Pseudocaranx dentex and sevenband grouper Epinephelus septemfasciatus. Among these chimeric viruses, SJNNV mutants containing the variable region of RGNNV RNA2 infected sevenband grouper larvae in a manner similar to RGNNV, while RGNNV mutants containing the variable region of SJNNV RNA2 infected striped jack larvae in a manner similar to SJNNV. Immunofluorescence microscopic studies using anti-SJNNV polyclonal antibodies revealed that these chimeric viruses multiplied in the brains, spinal cords and retinas of the infected fish, as in infections by the parental viruses. These results indicate that the variable region of RNA2 is sufficient to control host specificity in SJNNV and RGNNV. 相似文献
7.
Inhibitory Synapses on Pacemaker Neurons in the Heart Ganglion of a Stomatopod, Squilla oratoria 总被引:1,自引:1,他引:0
The pacemaker neurons of the Squilla heart ganglion are innervated from the CNS through three pairs of extrinsic nerves. One of them, the α-nerve, is inhibitory to the heart beat. The effect of α-nerve stimulation on the pacemaker potential was examined with intracellular electrodes. Without extrinsic nerve stimulation the membrane potential of the pacemaker cell fluctuated spontaneously. On application of a tetanic train of stimuli to the α-nerve the membrane potential was shifted and fixed to a steady level, which with K2SO4-filled electrodes was near the peak of hyperpolarization after a spontaneous burst, but was less negative with KCl-filled electrodes. The shift of the membrane potential was due to the summated IPSP's. By changing the level of the membrane potential with injection of the polarizing current the IPSP could be reversed in sign, and the size of the IPSP was linearly correlated with the membrane potential level. During inhibition the membrane conductance increased. The increase depended on divalent cation concentrations in the outside medium. In Ca-rich saline the IPSP was greatly enhanced. In Mg-rich saline it was suppressed. The amplitude of antidromic spikes was reduced during inhibition especially when the spike frequency was high. 相似文献
8.
Tatsuo?Saigo Jun?Tayama Toyohiro?Hamaguchi Naoki?Nakaya Tadaaki?Tomiie Peter?J?Bernick Motoyori?Kanazawa Jennifer?S?Labus Bruce?D?Naliboff Susumu?Shirabe Shin?FukudoEmail author 《BioPsychoSocial medicine》2014,8(1):10
Objective
The visceral sensitivity index (VSI) is a useful self-report measure of the gastrointestinal symptom-specific anxiety (GSA) of patients with irritable bowel syndrome (IBS). Previous research has shown that worsening GSA in IBS patients is related to the severity of GI symptoms, suggesting that GSA is an important endpoint for intervention. However, there is currently no Japanese version of the VSI. We therefore translated the VSI into Japanese (VSI-J) and verified its reliability and validity.Material and methods
Participants were 349 university students aged 18 and 19 years and recruited from an academic class. We analyzed data from the VSI-J, Anxiety Sensitivity Index (ASI), Hospital Anxiety and Depression scale (HAD), and Irritable Bowel Syndrome Severity Index (IBS-SI). The internal consistency, stability, and factor structure of the VSI-J and its associations with anxiety, depression and severity measures were investigated.Results
The factor structure of the VSI-J is unidimensional and similar to that of the original VSI (Cronbach’s α?=?0.93). Construct validity was demonstrated by significant correlations with ASI (r?=?0.43, p?<?0.0001), HAD-ANX (r?=?0.19, p?=?0.0003), and IBS-SI scores (r?=?0.45, p?<?0.0001). Furthermore, the VSI-J was a significant predictor of severity scores on the IBS-SI and demonstrated good discriminant (p?<?0.0001) and incremental (p?<?0.0001) validity.Conclusion
These findings suggest that the VSI-J is a reliable and valid measure of visceral sensitivity.9.
Toyama Yoshiro Murase Kimihiko Azuma Masanori Hamada Satoshi Tachikawa Ryo Tanizawa Kiminobu Handa Tomohiro Kubo Takeshi Hitomi Takefumi Oga Toru Hirai Toyohiro Chin Kazuo 《Sleep and biological rhythms》2018,16(1):117-124
Sleep and Biological Rhythms - Obstructive sleep apnea (OSA) is an established factor in the pathogenesis and exacerbation of fatty liver disease. However, randomized controlled trials have failed... 相似文献
10.
Katsutoshi Ando Yoshinori Okada Miki Akiba Takashi Kondo Tomohiro Kawamura Meinoshin Okumura Fengshi Chen Hiroshi Date Takeshi Shiraishi Akinori Iwasaki Naoya Yamasaki Takeshi Nagayasu Masayuki Chida Yoshikazu Inoue Toyohiro Hirai Kuniaki Seyama Michiaki Mishima Respiratory Failure Research Group of the Japanese Ministry of Health Labour Welfare 《PloS one》2016,11(1)