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71.
Miyata S Uchinokura S Fukushima T Hamasuna R Itoh H Akiyama Y Nakano S Wakisaka S Kataoka H 《Cancer letters》2005,227(1):83-93
Hepatocyte growth factor activator inhibitor type-1 (HAI-1) is an integral-membrane proteinase inhibitor. In this study, we examined the effects of HAI-1 on human glioblastoma cells. Two glioblastoma cell lines (YKG-1, U251) were stably transfected with expression plasmid harboring mature membrane-form or truncated secreted-form HAI-1. Culture characteristics were not altered by the expression of HAI-1, whereas in vitro invasiveness of U251 was suppressed. On the other hand, the expression of membrane-form HAI-1 resulted in significantly enhanced tumorigenicity of both cell lines in vivo. In contrast, secreted-form HAI-1 did not promote the tumorigenicity. These results suggest that HAI-1 may play complex roles in progression of glioblastoma cells, and membrane-form HAI-1 may mediate an undefined important signaling in the cells. 相似文献
72.
Copper-transporting P-type adenosine triphosphatase (ATP7B) is associated with cisplatin resistance 总被引:17,自引:0,他引:17
Komatsu M Sumizawa T Mutoh M Chen ZS Terada K Furukawa T Yang XL Gao H Miura N Sugiyama T Akiyama S 《Cancer research》2000,60(5):1312-1316
The accumulation of cisplatin is decreased in many cisplatin-resistant cell lines, and an active efflux pump for cisplatin exists in some of them, but it has not yet been identified. In this study, we transfected the copper-transporting P-type ATPase cDNA (ATP7B) into human epidermoid carcinoma KB-3-1 cells. The transfectant, KB/WD cell line, which overexpressed the P-type ATPase, ATP7B, was resistant to both cisplatin (8.9-fold) and copper (2.0-fold). The accumulation of cisplatin in KB/WD cells was lower than in mock-transfected KB/CV cells, and the efflux of cisplatin from KB/WD cells was enhanced compared with KB/CV cells. KB/WD cells were sensitive to other heavy metals, such as antimony, arsenate, arsenite, cadmium, and cobalt. ATP7B was overexpressed in cisplatin-resistant prostate carcinoma PC-5 cells but not in the parental PC-3 cells and the revertant PC-5R cells. ATP7B may be involved in cisplatin resistance in some tumors. 相似文献
73.
Osako T Takahashi K Iwase T Iijima K Miyagi Y Nishimura S Tada K Makita M Akiyama F Sakamoto G Kasumi F 《Breast cancer (Tokyo, Japan)》2007,14(2):229-233
PURPOSE: To confirm which modality, ultrasonography (US) or mammography (MMG), is useful to detect breast cancer in women aged 30 to 39 years, and to compare the sensitivity and findings of these two modalities for invasive carcinoma and ductal carcinoma in situ (DCIS) in the diagnostic setting. METHODS: We retrospectively evaluated the sensitivity and findings of these two modalities in 165 patients aged 30 to 39 years, who underwent surgery at the Cancer Institute Hospital between 2001 and 2003. US or MMG were performed after obtaining information on the other modalities previously used and physical examination. The abnormal findings of US were defined as mass lesions and focal hypoechoic areas due to breast cancer. The abnormal findings of MMG were defined as category 3 to 5 (Japanese Mammography Guidelines) masses, calcifications, and other findings due to cancer. RESULTS: Of 165 patients, 147 patients (89%) mammographically showed dense breasts. Histologically, 146 (88%) were invasive carcinomas and 19 (12%) were DCIS. In all carcinomas, the sensitivity of US (95%) was higher than that of MMG (85%). The sensitivity of US for invasive carcinoma (99%) was higher than that of MMG (85%). On the other hand, the sensitivity of MMG for DCIS (89%) was much higher than that of US (68%). CONCLUSIONS: US is more sensitive to detect breast cancers than MMG in this age range, especially for invasive carcinoma. On the other hand, MMG is useful for detecting DCIS, especially when it manifests with microcalcifications. 相似文献
74.
Yuki Tada Yukari Ueda Kemal Sasaki Shiro Sugiura Mieko Suzuki Hiromi Funayama Yuka Akiyama Mayu Haraikawa Kumi Eto 《Nutrients》2022,14(14)
The novel coronavirus-19 (COVID-19) pandemic has considerably impacted children’s lives. The aim of this study was to determine whether the pandemic affected mealtime regularity among preschool children and whether maintaining regular mealtimes or changes in mealtime regularity during the pandemic were related to dietary balance, including chronological relationships. This online cross-sectional survey involving individuals registered with a company that provides meals to children aged 2−6 years was conducted in February 2021. Using a 40-point scale, a healthy diet score (HDS) was developed to evaluate children’s dietary balance. The participants were divided into four groups based on their responses, and multiple regression analyses were performed with the HDS as the dependent variable. Maintaining regular mealtimes was associated with practices such as waking and going to bed earlier, less snacking, and eating breakfast every day. Even after adjusting for basic attributes, lifestyle habits, household circumstances, and other factors, regular mealtimes were still positively correlated with the HDS. These findings indicate that maintaining regular mealtimes is associated with higher HDS scores and better lifestyle habits. Furthermore, as the changed HDS was higher in the group whose mealtimes became regular during the pandemic, adopting regular mealtimes may lead to a more balanced diet. 相似文献
75.
Tetsuo Sekine Kyoichiro Tsuchiya Hiroyuki Uchinuma Sayaka Horiuchi Megumi Kushima Sanae Otawa Hiroshi Yokomichi Kunio Miyake Yuka Akiyama Tadao Ooka Reiji Kojima Ryoji Shinohara Zentaro Yamagata The Yamanashi Adjunct Study of the Japan Environment Childrens Study Group 《Journal of diabetes investigation.》2022,13(8):1444
Gestational diabetes mellitus (GDM) is one of the most common pregnancy‐related complications; it is associated with adverse pregnancy outcomes and metabolic disorders in offspring, consistent with the concept of the developmental origins of health and disease. This cohort study of women without diabetes (n = 761), who were part of the Yamanashi Adjunct Study of the Japan Environment and Children’s Study, aimed to explore the associations between maternal GDM and their offspring’s level of high‐sensitivity C‐reactive protein (hsCRP), a biomarker of inflammatory and cardiovascular diseases. We analyzed the associations between GDM and the offspring’s hsCRP levels using a multiple logistic regression model. A mother with GDM significantly increased the risk for high hsCRP level by 4.07‐fold (≥2.0 mg/L) in the child. As such, maternal GDM was significantly associated with increased serum hsCRP levels in 8‐year‐old children. 相似文献
76.
Biologic and clinical significance of the FLT3 transcript level in acute myeloid leukemia 总被引:23,自引:7,他引:23 下载免费PDF全文
77.
Terazono H Mutoh T Yamaguchi S Kobayashi M Akiyama M Udo R Ohdo S Okamura H Shibata S 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(11):6795-6800
A main oscillator in the suprachiasmatic nucleus (SCN) conveys circadian information to the peripheral clock systems for the regulation of fundamental physiological functions. Although polysynaptic autonomic neural pathways between the SCN and the liver were observed in rats, whether activation of the sympathetic nervous system entrains clock gene expression in the liver has yet to be understood. To assess sympathetic innervation from the SCN to liver tissue, we investigated whether injection of adrenaline/noradrenaline (epinephrine/norepinephrine) or sympathetic nerve stimulation could induce mPer gene expression in mouse liver. Acute administration of adrenaline or noradrenaline increased mPer1 but not mPer2 expression in the liver of mice in vivo and in hepatic slices in vitro. Electrical stimulation of the sympathetic nerves or adrenaline injection caused an elevation of bioluminescence in the liver area of transgenic mice carrying mPer1 promoter-luciferase. Under a light-dark cycle, destruction of the SCN flattened the daily rhythms of not only mPer1, mPer2, and mBmal1 genes but also noradrenaline content in the liver. Daily injection of adrenaline, administered at a fixed time for 6 days, recovered oscillations of mPer2 and mBmal1 gene expression in the liver of mice with SCN lesion on day 7. Sympathetic nerve denervation by 6-hydroxydopamine flattened the daily rhythm of mPer1 and mPer2 gene expression. Thus, on the basis of the present results, activation of the sympathetic nerves through noradrenaline and/or adrenaline release was a factor controlling the peripheral clock. 相似文献
78.
U S Sajjan L T Tran N Sole C Rovaldi A Akiyama P M Friden J F Forstner D M Rothstein 《Antimicrobial agents and chemotherapy》2001,45(12):3437-3444
Antimicrobial peptides are a source of novel agents that could be useful for treatment of the chronic lung infections that afflict cystic fibrosis (CF) patients. Efficacy depends on antimicrobial activity against the major pathogens of CF patients, Pseudomonas aeruginosa, Staphylococcus aureus, and Haemophilus influenzae, in the environment of the CF patient's airway. We describe the in vitro efficacies of derivatives of histatins, which are histidine-rich peptides produced by the salivary glands of humans and higher primates. P-113, a peptide containing 12 of the 24 amino acid residues of the parent molecule, histatin 5, retained full antibacterial activity and had a good spectrum of activity in vitro against the prominent pathogens of CF patients. However, P-113 was not active in the presence of purulent sputum from CF patients. In contrast, P-113D, the mirror-image peptide with the amino acid residues in the D configuration, was stable in sputum, was as active as P-113 against pathogens of CF patients in the absence of sputum and retained significant activity in the presence of sputum from CF patients. Recombinant human DNase, which effectively liquefies sputum, enhanced the activity of P-113D in undiluted sputum against both exogenous (added) bacteria and endogenous bacteria. Because of its properties, P-113D shows potential as an inhalant in chronic suppressive therapy for CF patients. 相似文献
79.
Higashi N Taniguchi M Mita H Kawagishi Y Ishii T Higashi A Osame M Akiyama K 《The Journal of allergy and clinical immunology》2004,113(2):277-283
BACKGROUND: The urinary leukotriene E4 (U-LTE4) concentration is significantly increased in patients with aspirin-intolerant asthma (AIA). However, the relationship between the clinicopathogenetic factors of asthma and the U-LTE4 concentration remains undetermined. OBJECTIVE: We sought to examine the clinical features of asthmatic patients with increased excretion levels of U-LTE4 (hyperleukotrienuria). METHODS: We measured the U-LTE4 concentrations in 137 asthmatic patients (including 64 patients with AIA) who were in clinically stable condition. A U-LTE4 concentration of 150 pg/mg creatinine or greater (mean U-LTE4 + 3 SDs of normal healthy control subjects) was indicative of hyperleukotrienuria. RESULTS: The basal concentration of U-LTE4 was significantly higher in the patients with AIA than in those with aspirin-tolerant asthma (ATA; median, 227.2 vs 90.3 pg/mg creatinine; P <.01). Compared with normal leukotrienuria in the patients with AIA, hyperleukotrienuria in the patients with AIA was associated with older age and decrease in pulmonary function. On the other hand, compared with normal leukotrienuria in the patients with ATA, hyperleukotrienuria in the patients with ATA was associated with severe asthma and chronic hyperplastic rhinosinusitis with nasal polyposis (CHRS/NP), which are well-known symptoms of the aspirin triad, as well as hypereosinophilia and anosmia. The patients with ATA with CHRS/NP excreted U-LTE4 at significantly high concentrations. There were significant decreases in the U-LTE4 concentrations before and after the sinus surgery in both the AIA and ATA groups (P <.05). CONCLUSION: Cysteinyl leukotrienes are not strictly associated with aspirin intolerance itself but rather with clinical features, such as CHRS/NP, that are similar to those seen in AIA. CHRS/NP might be involved in cysteinyl leukotriene overproduction in asthmatic patients. 相似文献
80.