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61.
T-cadherin (CDH13, H-cadherin) expression downregulated surfactant protein D in bronchioloalveolar cells 总被引:3,自引:0,他引:3
Takeuchi T Misaki A Fujita J Sonobe H Ohtsuki Y 《Virchows Archiv : an international journal of pathology》2001,438(4):370-375
T cadherin is a unique cadherin cell adhesion molecule that is anchored to the surface membrane through a glycosyl phosphatidyl inositol (GPI) moiety. In the present study, we postulated that T cadherin could regulate surfactant protein (SP)-D gene expression in human bronchioloalveolar type-II cells. We transfected A549 cells (human lung cancer cell line with alveolar type-II cell characteristics) with the T-cadherin expression vector. Both original and control plasmid-transfected A549 cells expressed SP-D; however, neither human nor murine T-cadherin-transfected A549 cells expressed SP-D mRNA. The downregulation of SP-D production in human T-cadherin-expressed A549 cells was also demonstrated using Western immunoblotting techniques. Control vector-transfected A549 cells showed a positive band of SP-D but not of T cadherin. In contrast, T-cadherin-transfected A549 cells, which expressed T-cadherin protein, did not produce SP-D. We further examined the relationship of T cadherin and SP-D expression in secondary pulmonary alveolar proteinosis associated with hematolymphoid malignancies. SP-D was detected in bronchioloalveolar type-II cells in alveolar proteinosis. However, little or no T-cadherin expression was detected in alveolar type-II cells in these patients. To our knowledge, this is the first report describing an effect of cadherin on SP production in bronchioloalveolar cells. 相似文献
62.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology》1993,67(4):354-359
Summary We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献
63.
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
64.
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
65.
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
66.
67.
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
68.
Hamaguchi T Takahashi A Manaka A Sato M Osada H 《International archives of allergy and immunology》2001,126(4):318-324
BACKGROUND: CD45, receptor-type protein tyrosine phosphatases (PTPases) are essential components of signaling through both the T cell receptor and the B cell antigen receptor. However, the functional significance of CD45 in the signaling pathway through the high-affinity immunoglobulin (Ig) E receptor has not yet been established. In this study, we demonstrate that the potent CD45 inhibitor negatively regulates IgE-dependent anaphylaxis and contact hypersensitivity reactions. METHOD: We have previously found that TU-572, 2-[(4-methylthiopyridin-2-yl)methylsulfinyl]-5-isopropoxybenzimidazole, had a potent and selective inhibitory effect against PTPase activity of CD45. Using a CD45 inhibitor, we examined in vitro and in vivo IgE-mediated responses. RESULTS: TU-572 potently inhibited histamine release from rat peritoneal mast cells and mouse systemic anaphylaxis reaction using monoclonal anti-dinitrophenyl (DNP) IgE and DNP-BSA. TU-572 also suppressed the immediate-type hypersensitivity response induced by repeated epicutaneous application of trinitrochlorobenzene in BALB/c mice. CONCLUSION: These findings revealed that the PTPase activity of CD45 played a critical role in signal transduction of IgE-mediated anaphylaxis in vitro and in vivo. PTPase inhibitors such as TU-572 are useful in the treatment of allergic diseases. 相似文献
69.
Akiko Hori Masahiro Kami Sung-Won Kim Aki Chizuka Rie Kojima Osamu Imataki Michiyo Sakiyama Tamae Hamaki Yasushi Onishi Noriko Usubuchi Yukiko Kishi Naoko Murashige Kinuko Tajima Shigesaburo Miyakoshi Yuji Heike Shigeru Masuo Shuichi Taniguchi Yoichi Takaue 《Biology of blood and marrow transplantation》2004,10(1):65-72
Little information is available on the clinical characteristics of infectious complications that occur in the early period after reduced-intensity stem cell transplantation (RIST). We retrospectively investigated the clinical features of neutropenic fever and infectious episodes within 30 days after RIST in 76 patients who had received fluoroquinolones as part of their antibacterial prophylaxis. Preparative regimens included cladribine 0.66 mg/kg or fludarabine 180 mg/m2 plus busulfan 8 mg/kg. All but 1 patient survived 30 days after transplantation, and 75 patients (99%) became neutropenic within a median duration of 9 days. Neutropenic fever was observed in 29 patients (38%), and bacterial infection was confirmed in 15 (20%) of these, including bacteremia (n = 13), bacteremia plus pneumonia (n = 1), and urinary tract infection (n = 1). The causative organisms were gram-positive (n = 9) and gram-negative organisms (n = 7), with a mortality rate of 6%. Neither viral nor fungal infection was documented. Multivariate analysis showed that the presence of neutropenia at the initiation of preparative regimens was an independent risk factor for subsequent documented bacterial infections (P =.026; 95% confidence interval, 1.25-35.1). We conclude that neutropenic fever and bacteremia remain common complications in RIST. 相似文献
70.
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