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31.
Hitoshi Nishimura Masashi Emoto Kenji Hiromatsu Shunsuke Yamamoto Keiko Matsuura Hiroshi Gomi Toshio Ikeda Shigeyoshi Itohara Yasunobu Yoshikai 《European journal of immunology》1995,25(5):1465-1468
The secretion of tumor necrosis factor (TNF)-α from macrophages is regulated by both priming and triggering signals. We found that macrophages from mice lacking γδ T cells [T cell receptor (TCR) δ?/- mice], which lack the gene encoding the δ chain, produced only small amounts of TNF-α in response to lipopolysaccharide (LPS) and showed a reduced level of expression of CD14. Pre-incubation of macrophages from TCR δ-/- mice with γδ T cells from their TCR δ+/- littermates restored their capacity to produce TNF-α in response to LPS. The priming activity of γδ T cells was in part inhibited by neutralizing anti-interferon (IFN)-γ monoclonal antibodies. Collectively, these results suggest that γδ T cells play a role in priming macrophages to a steady state of activation via IFN-γ secretion, which allows them to produce TNF-α when exposed to LPS. 相似文献
32.
Takuma Narita Shingo Hatakeyama Shintaro Narita Masahiro Takahashi Toshihiko Sakurai Sadafumi Kawamura Senji Hoshi Jiro Shimoda Toshiaki Kawaguchi Shigeto Ishidoya Koji Mitsuzuka Yoichi Arai Akihiro Ito Norihiko Tsuchiya Tomonori Habuchi Chikara Ohyama 《Translational andrology and urology》2021,10(1):417
BackgroundThe clinical benefit of the combined androgen blockade (CAB) therapy over luteinizing hormone-releasing hormone analog (LH-RHa) monotherapy for hormone naïve metastatic prostate cancer (mHNPC) is unclear. Therefore, we retrospectively compare the effectiveness of CAB with the LH-RHa monotherapy on the prognosis of Japanese patients with mHNPC.MethodsWe retrospectively evaluated the prognosis of 517 patients diagnosed with mHNPC between August 2001 and May 2017. The patients’ data were obtained from the Michinoku Urological Cancer Research Group database and Hirosaki University-related hospitals. Patients were divided into the CAB and LH-RHa monotherapy groups based on primary androgen deprivation therapy (ADT). Overall survival (OS), cancer-specific survival (CSS), and castrate-resistant prostate cancer-free survival (CRPC-FS) were compared between the two groups using the Kaplan-Meier curve analysis. Inverse probability of treatment weighting (IPTW)-adjusted Cox hazard proportional analyses was performed to investigate the effect of primary ADT on oncological outcomes.ResultsThe median age was 73 years old. The numbers of patients in the CAB and LH-RHa monotherapy groups were 447 and 70, respectively. The Kaplan-Meier curve analysis showed no significant differences in either 5-year OS (56.7% vs. 52.5%, P=0.277), CSS (61.1% vs. 56.4%, P=0.400), and CRPC-FS (33.1% vs. 31.1%, P=0.529) between the groups. IPTW-adjusted multivariate Cox hazard proportional analyses showed no significant differences in OS, CSS, and CRPC-FS between the two groups.ConclusionsNo significant differences in oncological outcomes were observed between the CAB and LH-RHa monotherapy groups in patients with mHNPC. 相似文献
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35.
Takahashi S Okada K Nagasawa H Shimada Y Sakamoto H Itoi E 《Virchows Archiv : an international journal of pathology》2004,444(5):454-458
We describe a case history of a 24-year-old male with osteogenesis imperfecta (OI) who developed osteosarcoma of the left thigh. High-dose ifosfamide therapy caused marked tumor regression of multiple lung metastases. Immunohistochemically, the tumor cells were diffusely positive for the p53 protein. Mutation of the p53 gene was not detected by direct genomic sequencing of exons 4–8. The radiographic characteristics, including irregularly distributed osteolytic lesions and cortical discontinuity, should not be confused with hyperplastic callus formation, a benign process. A biopsy is critical to establish the differential diagnosis between osteosarcoma and common hyperplastic callus formation in OI; however, it must be applied with great care. 相似文献
36.
Damon R Demady Ezra R Lowe Andrew C Everett Scott S Billecke Yasuhiko Kamada Anwar Y Dunbar Yoichi Osawa 《Drug metabolism and disposition》2003,31(7):932-937
It has been shown that administration of cigarette smoke to rats leads to loss of neuronal nitric-oxide synthase (nNOS) activity and nNOS protein in penile tissue. The exact mechanism for this loss of activity and protein is not known. In the current study, we investigated whether extracts prepared from cigarette smoke or from the cigarette itself could directly inhibit nNOS activity. We discovered that the cigarette smoke extract and the cigarette extract cause a time-, concentration-, and calmodulin-dependent inactivation of nNOS in an in vitro system containing the purified enzyme. L-Arginine, but not D-arginine, protects nNOS from this time-dependent inactivation, suggesting an active site directed event. The kinetics of inactivation are consistent with the metabolism-based or suicide inactivation of nNOS. Based on studies with other metabolism-based inactivators, this cigarette-mediated inactivation may render nNOS more susceptible to proteasomal degradation and thereby may explain the loss of nNOS protein in vivo. The component(s) responsible for nNOS inactivation is not volatile, is not retained by a 3,000 molecular weight cut-off membrane, binds to activated charcoal, and is highly water-soluble under both acidic and basic conditions. The discovery of a direct inactivation of nNOS by an organic, cationic compound(s) present in tobacco and tobacco smoke provides a basis for further study of not only the mechanisms responsible for the biological effects of tobacco but also a search for a potentially novel inactivator of nNOS. 相似文献
37.
Yumi Kojima Yoichi Aoki Hiroaki Kase Shoji Kodama Kenichi Tanaka 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(3):143-146
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging)
in the evaluation of preinvasive and early invasive cancer of the cervix.
Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion
underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated
for tumor detection and compared with results of histologic examination of the surgical specimens.
Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging,
whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and
5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images.
In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR
images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic
MR imaging.
Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced
MR imaging. 相似文献
38.
Characterization of mouse Ire1 alpha: cloning, mRNA localization in the brain and functional analysis in a neural cell line 总被引:2,自引:0,他引:2
Miyoshi K Katayama T Imaizumi K Taniguchi M Mori Y Hitomi J Yui D Manabe T Gomi F Yoneda T Tohyama M 《Brain research. Molecular brain research》2000,85(1-2):68-76
In yeast, an endoplasmic reticulum (ER)-associated protein, Ire1p, is believed to initiate the unfolded protein response (UPR), that is responsible for protein folding in the ER under stressed conditions. Two mammalian homologs of Ire1p have been identified, Ire1 alpha and Ire1 beta. We have previously reported that familial Alzheimer's disease linked presenilin-1 variants downregulate the signaling pathway of the UPR by affecting the phosphorylation of Ire1 alpha. In the present study, we cloned the mouse homolog of Ire1 alpha for generating genetically modified mice. Ire1 alpha was ubiquitously expressed in all mouse tissues examined, and was expressed preferentially in neuronal cells in mouse brain. This led us to investigate the effects of the downregulation of the UPR on the survival of neuronal cells under conditions of ER stress. Morphological and biochemical studies using a dominant-negative form of mouse Ire1 alpha have revealed that cell death caused by ER stress can be attributed to apoptosis, and that the downregulation of the UPR enhances the apoptotic process in the mouse neuroblastoma cell line, Neuro2a. Our results indicate that genetically modified mice such as transgenic mice with a dominant-negative form of Ire1 alpha might provide further understanding of the pathogenic mechanisms of Alzheimer's disease and other neurodegenerative disorders. 相似文献
39.
Kenji Suzuki Sakiko Morita Hideo Muraoka Yoichi Niimi 《Nihon Arukōru Yakubutsu Igakkai zasshi》2005,40(3):219-232
OBJECTIVE: This study was carried out to examine fetal alcohol spectrum disorders (FASD) among Japanese children of alcoholic mothers. This is the first report concerning FASD in Japan. METHODS: The subjects were 30 alcoholic women who were inpatients in the Kurihama Alcoholism Center and had given birth to children. They were subjected to a semi-structured interview by the author. Sixty healthy women who had not drunk during pregnancy were used as a control group, and they also underwent semi-structured interviews. The alcoholic women were divided into two groups, 13 who drunk during pregnancies and 17 who did not drink. Twenty children experienced of prenatal alcohol exposure and 40 children did not. The three groups; i.e., 13 alcoholic mothers who had drunk during pregnancy and their 20 children (ALD group), 17 alcoholic mothers who had not drunk during pregnancy and their 40 children (ALND group) and 60 non-alcoholic control mothers and their 80 children (Control group), were compared concerning the mothers' drinking problems and abnormal deliveries, children's birth weights, congenital abnormalities, abnormalities of the central nervous system and psychological problems. RESULTS: The mean age of onset of problem drinking of the mothers in the ALD group was significantly lower than that in the mothers of the ALND group, and some of the mothers in the ALD group showed alcohol dependence before their pregnancies. The mean birth weights of the children of the ALD group, ALND group and Control group were 2816 g, 3128 g and 3142 g, respectively and the differences were significant. The children of the ALD group had significantly more abnormal birth episodes, developmental retardation and psychiatric symptoms than those in the other two groups. Among 20 children in the ALD group, FASD was suspected in 6 children (10% of the children of alcoholic mothers). Six children had low birth weights, abnormal birth episodes, mental retardation and psychiatric symptoms. CONCLUSION: One third of the Japanese children of alcoholic mothers had experiences of prenatal alcohol exposure and 10% of them had suspected FASD abnormalities. 相似文献
40.
Ezra R Lowe Andrew C Everett Anthony J Lee Miranda Lau Anwar Y Dunbar Vladimir Berka Ah-Lim Tsai Yoichi Osawa 《Drug metabolism and disposition》2005,33(1):131-138
Smoking causes a dysfunction in endothelial nitric-oxide synthase (eNOS), which is ameliorated, in part, by administration of tetrahydrobiopterin (BH(4)). The exact mechanism by which the nitric oxide deficit occurs is unknown. We have previously shown that aqueous extracts of chemicals in cigarettes (CE) cause the suicide inactivation of neuronal NO synthase (nNOS) by interacting at the substrate-binding site. In the current study, we have found that CE directly inactivates eNOS by a process that is not affected by the natural substrate l-arginine and is distinct from the mechanism of inactivation of nNOS. We discovered that CE causes a time-, concentration-, and NADPH-dependent inactivation of eNOS in an in vitro system containing the purified enzyme, indicating a metabolic component to the inactivation. The CE-treated eNOS but not nNOS was nearly fully reactivated upon incubation with excess BH(4), suggesting that BH(4) depletion is a potential mechanism of inactivation. Moreover, in the presence of CE, eNOS catalyzed the oxidation of BH(4) to dihydrobiopterin and biopterin by a process attenuated by high concentrations of superoxide dismutase but not catalase. We speculate that a redox active component in CE, perhaps a quinone compound, causes oxidative uncoupling of eNOS to form superoxide, which in turn oxidizes BH(4). The discovery of a direct inactivation of eNOS by a compound(s) present in tobacco provides a basis not only for further study of the mechanisms responsible for the biological effects of tobacco but also a search for a potentially novel inactivator of eNOS. 相似文献