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81.
Kotoh K Nakamuta M Kohjima M Fukushima M Morizono S Kobayashi N Enjoji M Nawata H 《International journal of molecular medicine》2004,14(6):1049-1053
Liver cirrhosis is caused by a relative imbalance between synthesis and degradation of collagens. Arg-Gly-Asp (RGD) peptide is a major adhesive domain of several extracellular matrix (ECM) components, such as that involved in the binding of fibronectin to the alpha5beta1 integrin receptor. We previously reported that RGD peptide increased the expression of matrix metalloproteinase in hepatic stellate cells (HSCs) which play a major role in hepatic fibrosis. We evaluated whether RGD-peptides inhibit the progression of liver fibrosis in an animal model of carbon tetrachloride-induced hepatotoxicity. RGD peptide (GRGDS) (1 mg/kg body weight) was injected intraperitoneally (i.p.) 3 times a week for one month. The group treated with control peptide (GRGES) showed pathologically typical hepatic fibrosis, while the RGD-treated group showed minimal fibrotic changes. The liver contents of collagen and hydroxyproline in the RGD-treated group was significantly lower than that of the control group. Collagenase activity measured in liver homogenates was significantly higher in the treated group than in the control group. In an in vitro study using TWNT-4 cells derived from human HSCs, RGD peptide (100 mug/ml) reduced the expression of type I collagen and tissue inhibitor of matrix metalloproteinase-1, and increased that of matrix metalloproteinase-1. These results indicated that RGD peptides inhibited liver fibrosis associated with both decreased collagen production and increased collagenase acitivity, and suggested that RGD peptide might be useful for the therapy of hepatic fibrosis. 相似文献
82.
Nakashima Y Tagawa H Suzuki R Karnan S Karube K Ohshima K Muta K Nawata H Morishima Y Nakamura S Seto M 《Genes, chromosomes & cancer》2005,44(3):247-255
Natural killer (NK) cell lymphomas/leukemias are highly aggressive lymphoid malignancies, but little is known about their genomic alterations, and thus there is an urgent need for identification and analysis of NK cell lymphomas/leukemias. Recently, we developed our own array-based comparative genomic hybridization (array CGH) with an average resolution of 1.3 Mb. We performed an array CGH analysis for 27 NK-cell lymphoma/leukemia cases that were classified into two disease groups based on the World Health Organization Classification (10 aggressive NK-cell leukemia cases and 17 extranodal NK/T-cell [NK/T] lymphomas, nasal type). We identified the differences in the genomic alteration patterns of the two groups. The recurrent regions characteristic of the aggressive NK-cell leukemia group compared with those of the extranodal NK/T lymphoma, nasal-type group, were gain of 1q and loss of 7p15.1-p22.3 and 17p13.1. In particular, gain of 1q23.1-24.2 (P = 0.041) and 1q31.3-q44 (P = 0.003-0.047), and loss of 7p15.1-p22.3 (P = 0.012-0.041) and 17p13.1 (P = 0.012) occurred significantly more frequently in the former than in the latter group. Recurrent regions characteristic of the extranodal NK/T lymphoma, nasal-type group, compared with those of the other group were gain of 2q, and loss of 6q16.1-q27, 11q22.3-q23.3, 5p14.1-p14.3, 5q34-q35.3, 1p36.23-p36.33, 2p16.1-p16.3, 4q12, and 4q31.3-q32.1. Our results can be expected to provide further insights into the genetic basis of lymphomagenesis and the clinicopathologic features of NK-cell lymphomas/leukemias. 相似文献
83.
Status asthmaticus is defined as an attack of bronchial asthma that resists conventional treatment and continues for more than 24 hours. We report here about patients with status asthmaticus who were successfully treated with isoflurane inhalation. Of the 19 patients who were transferred to the intensive care unit (ICU) and underwent mechanical ventilation from January 1996 to May 2001, eleven patients who were first treated by isoflurane inhalation were targeted in this study. Their improvement was assessed 6 and 24 hours after anesthesia compared with their condition before anesthesia. The tidal volume, pH, and PaCO2 improved within 6 hours after anesthesia. For the next step, among the patients who were transferred to the critical care center soon after an attack of bronchial asthma and underwent mechanical ventilation, 8 patients who were treated by isoflurane inhalation anesthesia (Group I) and another 4 patients who were not treated by isoflurane (Group NI) were compared to assess the usefulness of isoflurane inhalation therapy. The patients in Group I stayed in the ICU and underwent mechanical ventilation for a shorter period. These patients had hypotension and liver dysfunction after the inhalation anesthesia, but these symptoms were improved by decreasing the concentration of isoflurane. Isoflurane inhalation therapy seemed useful for intractable status asthmaticus, and earlier introduction of this therapy is expected to achieve a greater therapeutic effect. 相似文献
84.
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
85.
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
86.
Ken-Ichi Maeda Hideyuki Nagasawa Atsuko Furukawa Hajime Hisaeda Yoichi Maekawa Tetsuya Manabe Eiji Kudo Robert A. Good Kunisuke Himeno 《European journal of immunology》1993,23(12):3151-3157
To examine the development of T cells within an allogeneic or xenogeneic environment, we engrafted the fetal thymus from AKR mice or F344 rats under the kidney capsule of SCID mice (mTG and rTG mice). T lymphopoiesis developed in SCID mice 2 months after transplantation, although the ratio of CD4/CD8 in both experimental groups was different from that of normal control. T cells in mTG mice did not show in vitro proliferation or cytotoxicity against either host-type C.B-17 (H-2d) or donor-type AKR (H-2k) cells, while they exerted potent activities against third-party BIO (H-2b) cells. In contrast, T cells in rTG mice exhibited proliferation against both host-type C.B-17 and donor-type F344 rat cells. Consistently, graft-vs.-host disease symptoms developed in these mice and histological examination showed impressive infiltration of lymphocytes into the skin or into the mucosal layers of the stomach. Activated state of T cells in rTG mice was also evidenced by the positive expression of interleukin-2 receptor. Taken together, fetal thymus appears to contain progenitor cells which are sufficient for in vivo reconstitution of T lymphopoiesis, but species-specific environment is important for the induction of tolerance. In mTG mice, Vβ6+ T cells reactive to donor Mlsa determinants and Vβ3+ T cells reactive to host Mlsc determinants were deleted, suggesting that tolerance was regulated mainly by clonal deletion. By contrast, Vβ11+ T cells reactive to Mlsf determinants were not deleted possibly due to the lack of their ligands. 相似文献
87.
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
88.
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
89.
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
90.
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