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71.
Apoptotic body engulfment by a human stellate cell line is profibrogenic 总被引:22,自引:0,他引:22
Canbay A Taimr P Torok N Higuchi H Friedman S Gores GJ 《Laboratory investigation; a journal of technical methods and pathology》2003,83(5):655-663
Hepatocyte apoptosis and stellate cell activation are both features of chronic liver diseases, but a relationship between these events has not been explored. In macrophages, engulfment of apoptotic bodies induces expression of transforming growth factor-beta (TGF-beta), a profibrogenic cytokine. We examined whether a similar response occurs in stellate cells. Fluorescently labeled hepatocyte apoptotic bodies were added to cultures of primary and immortalized human stellate cells. Stellate cells, but not hepatocytes, readily engulfed apoptotic bodies in a time-dependent manner as assessed by confocal microscopy. The activation of primary and immortalized human stellate cells after incubation with apoptotic bodies, as well as their fibrogenic activity, was indicated by an increase in alpha-smooth muscle actin (primary cells), TGF-beta1, and collagen alpha1(I) mRNA (primary and immortalized cells). The profibrogenic response was dependent upon apoptotic body engulfment, because nocodazole, a microtubule-inhibiting agent, blocked both the engulfment and the increase of TGF-beta1 and collagen alpha1(I) mRNA. As described in primary rodent stellate cells, up-regulation of collagen alpha1(I) mRNA was inhibited by a PI-3K inhibitor (LY294002) and a p38 mitogen-activated protein kinase inhibitor (SB203580) in LX-1 cells. In conclusion, these data support a model in which engulfment of hepatocyte apoptotic bodies by stellate cells leads to a fibrogenic response by eliciting a kinase-signaling pathway. 相似文献
72.
Nakamura H 《Rinsho byori. The Japanese journal of clinical pathology》2003,51(2):109-114
Although excess amounts of oxidative stress damage proteins and nucleotides, small amounts of oxidative stress transduce intracellular signals for cellular activation, differentiation and proliferation. Reduction/oxidation(redox) regulation is defined as a biological response to maintain homeostasis against oxidative stress. Thioredoxin, a 12 kD small protein with a redox-active dithiol/disulfide in the conserved active site: -Cys-Gly-Pro-Cys-, is a key molecule for redox regulation as well as glutathione(GSH). Thioredoxin is induced by a variety of oxidative stresses and secreted from cells. Thioredoxin plays crucial roles as a redox-regulator of intracellular signal transduction and as a radical scavenger. Plasma levels of thioredoxin are good biomarkers for oxidative stress. Thioredoxin-transgenic mice are more resistant to cerebral infarction, infection or inflammation and survive longer than control mice. Administration of thioredoxin may have a good potential for anti-aging and anti-stress effects. Redox regulation mechanisms by thioredoxin and other thioredoxin family members will clarify the pathophysiology of oxidative stress-associated disorders. 相似文献
73.
Thioredoxin and its related molecules: update 2005 总被引:10,自引:0,他引:10
Nakamura H 《Antioxidants & redox signaling》2005,7(5-6):823-828
Studies on thioredoxin (Trx) and its related molecules have expanded dramatically recently. Proteins that share the similar active-site sequence, -Cys-Xxx-Yyy-Cys-, are called the Trx family, and the number of Trx family members is increasing. Trx reductase, which reduces oxidized Trx in cooperation with NADPH, has three isoforms, and peroxiredoxin, which is Trx-dependent peroxidase, has six isoforms. In addition to a role as an antioxidant, Trx and its related molecules play crucial roles in the redox regulation of signal transduction. The classical cytosolic Trx1 and truncated Trx80 are released from cells. Plasma/serum levels of Trx1 are good markers for oxidative stress. Exogenous Trx1 shows cytoprotective and antiinflammatory effects and has a good potential for clinical application. This is an update review on Trx and its related molecules. 相似文献
74.
Hideyuki Arima Yu Yamato Kimihito Sato Yoshihiro Uchida Toshiyuki Tsuruta Kanehisa Hashiguchi Hajime Hamamoto Eiichiro Watanabe Kaoru Yamanaka Tomohiko Hasegawa Go Yoshida Tatsuya Yasuda Tomohiro Banno Shin Oe Hiroki Ushirozako Tomohiro Yamada Koichiro Ide Yuh Watanabe Yukihiro Matsuyama 《Journal of orthopaedic science》2021,26(4):577-583
BackgroundSagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP.MethodOf the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2–C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group).ResultsThe prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637).ConclusionsThis study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively.Level of evidenceⅣ 相似文献
75.
Drs Hideo Tanaka Drs Tomohiko Hiyama Drs Hideaki Tsukuma Drs Yasuto Okubo Drs Hajime Yamano Drs Akira Kitada Drs Isaburo Fujimoto 《Cancer causes & control : CCC》1994,5(5):409-413
To clarify the demographic characteristics of the prevalence of hepatitis C virus (HCV) infection in Osaka, Japan, where hepatocellular carcinoma is common, we investigated the screening data of antibody to HCV (anti-HCV, DAINABOTHCVPHA, second generation assay) in 197,600 voluntary blood donors residing in Osaka. The study found that age-standardized prevalence of anti-HCV was significantly higher than that of HBsAg (2.25cf 0.86 percent among males,P<0.001; 2.17cf 0.55 percent among females,P<0.001. It was much higher in the blood donors aged 55–64 years than in those aged 16–54 years (8.49cf 1.32 percent among males,P<10–5; 7.26cf 1.42 percent among females,P<10–5). The prevalence of anti-HCV among males was significantly higher than that of females in the younger (25–34 years) generations (1.02 to 1.49 percentcf 0.71 to 1.13 percent,P<0.05). A similar tendency was observed in the prevalence of high-titer (212) anti-HCV. The number of coinfection (both HBsAg and anti-HCV seropositive) was very small, and it was not statistically different from the expected number. 相似文献
76.
Primary anorectal malignant melanoma: Report of a case 总被引:3,自引:0,他引:3
Ojima Y Nakatsuka H Haneji H Kurihara T Sadamoto S Ohmoto T Katayama N Taniyama K 《Surgery today》1999,29(2):170-173
(Received for publication on Aug. 18, 1997; accepted on May 15, 1998) 相似文献
77.
Microsomal Cytochrome P-450 Monooxygenase System and Its Drug-metabolizing Activity after Partial Portal Vein Ligation in the Rat 总被引:1,自引:0,他引:1
Kunihiko Izuishi Hisao Wakabayashi Yasutaka Kokudo Takashi Maeba Munemasa Ryu Hajime Maeta 《World journal of surgery》1999,23(1):6-11
RID=" ID=" <E5>Correspondence to:</E5> K. Izuishi, M.D. 相似文献
78.
Y. Fukuda Yoshihisa Fukuta Raita Higashino Masayuki Ogishima Kenji Yoshida Hajime Tamaki Mineo Takei 《Naunyn-Schmiedeberg's archives of pharmacology》1999,359(6):433-438
The effects of Z-350, (S)-4-[3-(4-{1-(4-methylphenyl)-3-[4-(2-methoxyphenyl)piperazine-1-yl]propoxy} benzoyl)indole-1-yl]butyric
acid hydrochloride, a newly synthesized compound possessing α1-adrenoceptor antagonistic and steroid 5α-reductase inhibitory actions, were studied in vitro. In functional experiments,
Z-350 shifted the concentration/response curve for the phenylephrine-induced contraction of rabbit prostate, urethra and aorta
to the right with pA2 values of 8.04, 7.57 and 7.13, respectively. The binding affinity of Z-350 for α1-adrenoceptors in rabbit prostate, urethra and aorta were estimated by the displacement of [3H]prazosin. The pK
i values for this action of Z-350 were 7.53, 7.95 and 7.62 for the prostate, urethra and aorta, respectively. α1-Adrenoceptor subtype selectivities were studied in the submaxillary gland (α1A) and liver (α1B) of rat. Z-350 inhibited the specific binding of [3H]prazosin to α1A and α1B-adrenoceptors with pK
i values of 7.82 and 7.29, respectively. Z-350 inhibited rat prostatic steroid 5α-reductase non-competitively with a pIC50 of 8.42. These results indicate that Z-350 is a α1-adrenoceptor antagonist and is a steroid 5α-reductase inhibitor. It is expected that Z-350 will be a candidate drug for the
treatment of benign prostatic hyperplasia.
Received: 26 January 1999 / Accepted: 2 March 1999 相似文献
79.
M Kamberi N Hajime P Kamberi N Uemura K Nakamura S Nakano 《Therapeutic drug monitoring》1999,21(3):335-340
A specific and sensitive reversed-phase high-performance liquid chromatographic (HPLC) method has been developed and validated for the simultaneous determination of grepafloxacin, ciprofloxacin, and theophylline in human plasma and urine. This assay allows these drugs to elute and be resolved in a single chromatogram at 280 nm, using a linear gradient. The procedure involves liquid-liquid extraction. Separation was achieved on a C18 reversed-phase column. The quantification limits were 0.05 mg/L in plasma and 0.5 mg/L in urine for grepafloxacin and ciprofloxacin and 0.5 mg/L in plasma and urine for theophylline. Standard curves were linear (correlation coefficients >0.999) over the ranges 0.05 to 5 mg/L for grepafloxacin and ciprofloxacin in plasma, from 0.5 to 20 mg/L for theophylline in plasma, and from 0.5 to 500 mg/L for the three drugs in urine. The coefficients of variation for the three drugs were less than 10% for within- and between-day analyses. The recoveries averaged 94.5% for theophylline, 93% for ciprofloxacin, 93.7% for grepafloxacin, and 95.1% for the internal standard (IS). The assay can be used for pharmacokinetic studies of these drugs, to investigate the interaction of grepafloxacin and ciprofloxacin with theophylline, or for routine simultaneous monitoring of theophylline, grepafloxacin, and ciprofloxacin. 相似文献
80.
The ultrastructure of parapapillary chorioretinal atrophy in eyes with secondary angle closure glaucoma 总被引:4,自引:0,他引:4
Toshiaki Kubota Ursula M. Schlötzer-Schrehardt Gottfried O. H. Naumann Toshihiko Kohno Hajime Inomata 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1996,234(6):351-358
Background: The present study was performed to investigate the ultrastructure of deep retinal layers and choroid corresponding to the parapapillary chorioretinal atrophy in eyes with secondary angle-closure glaucoma. Methods: The glaucomatous eyes included two eyes enucleated due to iris ring melanoma with high intraocular pressure and one eye with neovascular glaucoma enucleated due to ocular pain. The control eyes included one eye enucleated due to choroidal malignant melanoma with normal intraocular pressure and one eye enucleated during surgery for supramandibular carcinoma. These eyes were studied with light and electron microscopy. Results: In the region of parapapillary chorioretinal atrophy of glaucomatous eyes, the retinal pigment epithelial cells showed degenerative changes, such as loss of basal in foldings and microvilli, degenerated mitochondria, vacuolar degeneration and irregular distribution of melanin granules. The photoreceptors were decreased in number in this area of glaucomatous eyes. The lumen of the choriocapillary vessels adjacent to the optic nerve was collapsed. Conclusion: These results elucidate the fine structures of deep retina and choroid in the region of parapapillary chorioretinal atrophy of glaucomatous eyes, and suggest that the reduced choroidal perfusion might be the pathogenetic mechanism of glaucomatous parapapillary chorioretinal atrophy. 相似文献