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41.
Akiko Arata H. Onimaru Ikuo Homma 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,119(4):399-408
We analysed the modulation of respiratory neurons by adrenaline or noradrenaline (NA) in a newborn rat brainstem-spinal cord
preparation. Adrenaline or NA caused a dose-dependent depression of the respiratory rhythm and induced C4 spinal tonic discharges.
The inhibitory effect of adrenaline (ED50=0.5 μM) on the respiratory rhythm was stronger than NA (ED50=5 μM). The adrenaline respiratory rhythm depression was partially blocked by the α1-antagonist prazosin or by the α2-antagonist yohimbine. The C4 tonic discharge elicited by adrenaline was blocked by the α1-antagonist prazosin. The direct effects of adrenaline on pre-inspiratory (Pre-I) neurons were examined in a synaptic blockade
solution (low Ca), and fifty-six percent of Pre-I neurons were found to continue firing. In low-Ca solution, Pre-I neurons
were excited (n=29 of 39) or depressed (n=5 of 39) by adrenaline, and excited by α1-agonist phenylephrine or depressed by α2-agonist clonidine. These results suggest that the respiratory rhythm depression under intact network conditions is mediated
by some other inhibitory system. The inhibitory effect of adrenaline on the respiratory rhythm was partially blocked by the
GABAA-antagonists bicuculline or picrotoxin, but not by the GABAB-antagonist phaclofen. The present results suggest that: (1) respiratory rhythm generation is more sensitive to adrenaline
than NA through α-adrenergic action of adrenaline; (2) the activity of Pre-I neurons could be directly regulated by excitation
via α1-receptors and inhibition via α2-receptors; and (3) the depression of the respiratory rhythm by adrenaline is partly mediated by GABAAergic neurons.
Received: 8 April 1997 / Accepted: 6 October 1997 相似文献
42.
Yokomizoi K Nakayama A Hokazono E Ninomiya A Miyake R Hiratsuka N Okuyama M Kato Y Kobayashi S Ito Y Shiba K 《Rinsho byori. The Japanese journal of clinical pathology》2005,53(12):1109-1115
In order to investigate the mechanism of urinary tract stone formation, we analyzed protein components in urine and the stone. Urinary proteins of healthy subjects and urolithic patients as well as protein components urinary tract stone of the urolithic patients were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Electrophoretic patterns of urinary proteins of the patients differed from those of healthy subjects after separating protein patterns into those larger than 66kDa or smaller than 30kDa. Protein constituents of urinary tract stone were mainly separated into 18 bands ranging from 26.8 to 143 kDa. Major bands among these 18 bands differed among stones from different patients. On western blotting, the developed intensities of Tamm-Horsfall protein (THP) were fainter than those of healthy subjects. Whereas intensities of albumin (ALB) were stronger than those of healthy subjects. Moreover, blotting patterns of THP of the patients on non-reducing SDS-PAGE were obviously broad. Thus, we suggest that analysis of fractionated urinary proteins or protein components of urinary tract stone may provide a tool for monitoring the prognosis or relapse in the patients. 相似文献
43.
Hoshino S Ohkoshi N Ishii A Shoji S 《Journal of muscle research and cell motility》2002,23(2):139-145
We investigated the expression of neuronal nitric oxide synthase (nNOS) and dystrophin in the regenerating skeletal muscles
of rats after cardiotoxin-induced myonecrosis by immunohistochemical studies and western blot analysis. In normal muscles,
nNOS was moderately immunostained on type 2B fibers, but was faintly immunostained on type 2A or type 1 fibers. In immunohistochemical
studies of regenerating muscles, nNOS was first observed at the sarcolemma of type 2B fibers on day 10, when the type discrimination
between types 2A and 2B was first detected by ATP reactions. Subsequently, the immunostaining of nNOS grew progressively stronger
in type 2B fibers, with faint staining in type 2A and type 1 fibers until day 28. Meanwhile, the immunostaining of dystrophin
grew stronger equally in all three fibers until day 21. In western blot analysis of regenerating muscles, nNOS regenerated
more slowly than dystrophin. The present data suggest that the expression of nNOS is related to the muscle fiber type differentiation,
and that the role of nNOS is related to the function of the type 2B fibers of the muscle.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
44.
45.
A novel insertional mutation at exon VII of the myelin proteolipid protein gene in Pelizaeus -- Merzbacher disease 总被引:1,自引:0,他引:1
Kurosawa Kenjl; Iwakl Akiko; Miyake Sho-ta; Imaizuml Kiyoshi; Kuroki Yoshikazu; Fukumakl Yasuyuki 《Human molecular genetics》1993,2(12):2187-2189
Pelizaeus Merzbacher disease (PMD) is an X-linked neurologicaldisorder characterized by dysmyelination in the central nervoussystem (CNS). Recently mutations of the myelln proteollpid protein(PLP) gene which encodes both PLP and Its Isoform, DM-20 generatedby alternative spllcing, have been demonstrated In PMD patients.We analyzed the seven exons of the PLP gene of a Japanese boyaffected with PMD by direct sequencing and identified an Insertionevent In exon Vll of the PLP gene. This mutation was also presentIn his carrier mother, but was absent In ninety-five X chromosomesof normal Japanese. The frame-shift mutation leads to the productionof truncated PLP with altered carboxyl terminal amlno acid sequences,resulting In conslderable change of the structure of PLP andDM-20 necessary for functional purposes. This is the first reportof a mutation In exon Vll of the PLP gene associated with PMD. 相似文献
46.
A pore-forming toxin produced by Aeromonas sobria activates Ca2+ dependent Cl- secretion 总被引:1,自引:0,他引:1
Takahashi A Tanoue N Nakano M Hamamoto A Okamoto K Fujii Y Harada N Nakaya Y 《Microbial pathogenesis》2005,38(4):173-180
Bacteria produce many types of hemolysin that induce diarrhea by mechanisms that are not completely understood. Aeromonas sobria hemolysin (ASH) is a major virulence factor produced by A. sobria, a human pathogen that causes diarrhea. Since epithelial cells in the intestine are the primary targets of hemolysin, we investigated the effects of ASH on ion transport in human colonic epithelial (Caco-2) cells. ASH increased short-circuit currents (Isc) in a dose-dependent manner, and it also activated a 125I efflux from Caco-2 cells. ASH-induced Isc increases and 125I efflux activations were both suppressed by low Ca2+ levels in the extracellular solution or by pretreatment with the Ca2+ chlelator BAPTA-AM. Intracellular Ca2+ levels were increased by ASH in a biphasic fashion characterized by a rapid sharp increase (peak 1) followed by a sustained low plateau (peak 2). ASH-induced peak 1 was inhibited by pretreatment with pertussis toxin, indicating that Ca2+ was mobilized from intracellular stores, and peak 2 was induced by an influx of extracellular Ca2+. Peak 2 but not peak 1 was related to Cl- secretion. These results indicate that ASH activates Ca2+-dependent Cl- secretion. 相似文献
47.
Takaaki Hayashi Katsuhiro Hosono Akiko Kubo Kentaro Kurata Satoshi Katagiri Kei Mizobuchi Minehiro Kurai Norihito Mamiya Mineo Kondo Toshiaki Tachibana Hirotomo Saitsu Tsutomu Ogata Tadashi Nakano Yoshihiro Hotta 《American journal of medical genetics. Part A》2020,182(6):1500-1505
Mucolipidosis type IV (MLIV) is an autosomal recessively inherited lysosomal storage disorder characterized by progressive psychomotor delay and retinal degeneration that is associated with biallelic variants in the MCOLN1 gene. The gene, which is expressed in late endosomes and lysosomes of various tissue cells, encodes the transient receptor potential channel mucolipin 1 consisting of six transmembrane domains. Here, we described 14‐year follow‐up observation of a 4‐year‐old Japanese male MLIV patient with a novel homozygous in‐frame deletion variant p.(F313del), which was identified by whole‐exome sequencing analysis. Neurological examination revealed progressive psychomotor delay, and atrophy of the corpus callosum and cerebellum was observed on brain magnetic resonance images. Ophthalmologically, corneal clouding has remained unchanged during the follow‐up period, whereas optic nerve pallor and retinal degenerative changes exhibited progressive disease courses. Light‐adapted electroretinography was non‐recordable. Transmission electron microscopy of granulocytes revealed characteristic concentric multiple lamellar structures and an electron‐dense inclusion in lysosomes. The in‐frame deletion variant was located within the second transmembrane domain, which is of putative functional importance for channel properties. 相似文献
48.
Hidenori Takahashi Hiroyoshi Takano Akiko Yokoyama Yoshiaki Hara Shigeyuki Kawano Akio Toh-e Tsuneyoshi Kuroiwa 《Current genetics》1995,28(5):484-490
Based on the results of cytological studies, it has been assumed that Cyanidioschyzon merolae does not contain actin genes. However, Southern hybridization of C. merolae cell-nuclear DNA with a yeast actin-gene probe has suggested the presence of an actin gene in the C. merolae genome. In the present study, an actin gene was isolated from a C. merolae genomic library using a yeast actin-gene probe. The C. merolae actin gene has no intron. The predicted actin is composed of 377 amino acids and has an estimated molecular mass of 42003 Da. Southern hybridization indicated that the C. merolae genome contains only one actin gene. This gene is transcribed at a size of 2.4 kb. When Southern hybridization was performed with C. merolae chromosomes separated by pulsed-field gel electrophoresis, a band appeared on unseparated chromosomes XI and XII. A phylogenetic tree based on known eucaryote actin-gene sequences revealed that C. merolae diverged after the division of Protozoa, but before the division of Fungi, Animalia and Chlorophyta. 相似文献
49.
Kikuchi T Ichimiya S Kojima T Crisa L Koshiba S Tonooka A Kondo N Van Der Saag PT Yokoyama S Sato N 《International immunology》2004,16(6):831-841
In this study, we investigated the localization and functional significance of p53 tumor suppressor-like molecules, p63 and p73, in human thymic epithelial cells (TECs). Immunohistochemical studies showed particular distribution profiles of p63 and p73 in thymic epithelium, in which cortical TECs preferentially expressed p63 in their nuclei whereas subcapsular and medullary TECs expressed both p63 and p73 in their nuclei. The wide distribution of p63 in TECs was further suggested by studies using TECs of primary culture. In vitro studies using two human TEC lines demonstrated that p63 was capable of up-regulating intercellular adhesion molecule-1 (ICAM-1) and enhancing the production of IL-6 and IL-8. Moreover, in vitro studies also indicated that p73, but not p63, had the capacity to induce granulocyte macrophage colony stimulating factor (GM-CSF) and granulocyte colony stimulating factor (G-CSF) in the TEC lines. These findings suggest that p63 would regulate the cell adhesive property through ICAM-1/LFA-1 interaction and the production of IL-6 and IL-8, probably in all TEC subtypes. p73 in subcapslar and medullary TECs was suggested to play a role in the regulation of the production of GM-CSF and G-CSF, which might stimulate other stromal cells such as dendritic cells, macrophages and endothelial cells around these regions. 相似文献
50.
Purification and Characterization of Thermostable Direct Hemolysin of Vibrio parahaemolyticus 总被引:8,自引:12,他引:8 下载免费PDF全文
A thermostable direct hemolysin was purified from culture filtrates of Vibrio parahaemolyticus. The purified hemolysin gave one precipitation line with the antihemolysin antiserum on agar-gel diffusion test and a single band on polyacrylamide gel electrophoresis. The hemolysin was not inactivated by heating at 70 to 100 C for 10 min. The hemolytic activity was not enhanced by the addition of lecithin. It was demonstrated that the hemolysin was a protein with a molecular weight of approximately 118,000. Amino acid analysis revealed that 43% of total amino acids were acidic amino acids, whereas 11% were basic amino acids. 相似文献