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51.
Vihko P Härkönen P Soronen P Törn S Herrala A Kurkela R Pulkka A Oduwole O Isomaa V 《Molecular and cellular endocrinology》2004,215(1-2):83-88
17 beta-Hydroxysteroid dehydrogenases (17HSDs) regulate the biological activity of sex steroid hormones in a variety of tissues by catalyzing the interconversions between highly active steroid hormones, e.g. estradiol and testosterone, and corresponding less active hormones, estrone and androstenedione. Epidemiological and endocrine evidence indicates that estrogens play a role in the etiology of breast cancer, while androgens are involved in mechanisms controlling the growth of normal and malignant prostatic cells. Using LNCaP prostate cancer cell lines, we have developed a cell model to study the progression of prostate cancer. In the model LNCaP cells are transformed in culture condition into more aggressive cells. Our data suggest that substantial changes in androgen and estrogen metabolism occur in the cells, leading to increased production of active estrogens during the process. In breast cancer, the reductive 17HSD type 1 activity is predominant in malignant cells, while the oxidative 17HSD type 2 mainly seems to be present in non-malignant breast epithelial cells. Deprivation of an estrogen response by using specific 17HSD type 1 inhibitors is a tempting approach in treating estrogen-dependent breast cancer. Our recent studies demonstrate that in addition to sex hormone target tissues, estrogens may be important in the development of cancer in some other tissues previously not considered to be estrogen target tissues, such as the gastrointestinal tract. 相似文献
52.
Hilkka E. Pernu Kyösti Oikarinen Jarkko Hietanen Matti Knuuttila 《Journal of oral pathology & medicine》1989,18(7):422-425
Verapamil-induced overgrowth was most prominent in the anterior regions and interproximal areas associated with plaque retention. Despite periodontal therapy, overgrowths recurred 1 month after gingivectomy. Discontinuation of the drug resulted in regression of the overgrowths. Histologic findings showed inflamed connective tissue covered by an acanthotic, thickened oral epithelium with long rete pegs containing dyskeratotic pearls. The proliferation rate and protein and collagen production of fibroblasts from the overgrowth sites were markedly lower than in the control cells cultured from healthy gingiva. Incubation of fibroblasts in the presence of verapamil reduced protein and collagen synthesis. 相似文献
53.
R G Parker H C Berry A J Gerdes M D Soronen C M Shaw 《AJR. American journal of roentgenology》1976,127(2):331-335
Twenty-one patients with glioblastoma multiforme were treated with fast neutron beam irradiation of the whole brain. Therapy was well tolerated up to calculated doses of 1.850 radn+y in 12-18 increments over 6 weeks. The survival rate 6 month after initiation of treatment was 62%, not significantly different from conventional photon therapy; average posttreatment survival appears to be shortened compared to photon therapy. No improvement or prolonged maintenance of existing neurologic function was observed. Autopsy findings in seven patients showed replacement of tumor by coagulative necrosis persisting at least 16 months posttreatment, paucity of tumor cells with infrequent mitosis, and suppression of macrophage response. These findings differ from those in conventionally irradiated patients. No treatment-related changes were documented by conventional gross and histologic studies of the irradiated brains distant from the tumors. Thus the deaths of patients in this study appear to be related to unexplained causes other than progressive growth of tumor. 相似文献
54.
Fumonisin B1-induced apoptosis in neuroblastoma, glioblastoma and hypothalamic cell lines 总被引:1,自引:0,他引:1
Stockmann-Juvala H Naarala J Loikkanen J Vähäkangas K Savolainen K 《Toxicology》2006,225(2-3):234-241
Fumonisin B(1) (FB(1)) is a mycotoxin produced by Fusarium verticilliodes, which commonly infects corn across the world. Fusarium fungi may also be found in moisture-damaged buildings. In this study, we investigated the role of apoptosis in the toxicity of FB(1) in four different cell lines. Activation of caspase-3-like protease, DNA fragmentation and expression of p53 and Bcl-2 family proteins were studied in mouse GT1-7 hypothalamic, rat C6 glioblastoma, human U-118MG glioblastoma, and human SH-SY5Y neuroblastoma cells exposed to 0.1-100microM FB(1) for 0-144h. Caspase-3-like protease activity increased in all cell lines, except SH-SY5Y, at 48-144h, and internucleosomal DNA fragmentation occurred in all of the cell lines, pointing to a role for apoptosis in the toxicity of FB(1). However, the expressions of p53 or pro- or antiapoptotic Bcl-2 family proteins (Bax, Bcl-2, Bcl-X(L) and Mcl-1) were not affected in any of the cell lines even after prolonged exposure to FB(1) at high doses. The results of this study, together with the results of our previous studies, provide evidence that FB(1) is a potential neurotoxin, but that the toxicity of FB(1) varies between different cell lines. The sensitivity of these cell lines towards FB(1) is as follows: U-118MG>GT1-7>C6>SH-SY5Y cells. These results are consistent with the assumption that cells of glial origin may be more sensitive towards FB(1) than cells of neural origin. 相似文献
55.
Five enclosed double-stranded RNA (dsRNA) bands in electrophoresis, probably of viral origin, were found from a single isolate (SurS4) of Gremmeniella abietina var. abietina type A. Analysis of the dsRNAs revealed that they represented three different viruses, named as Gremmeniella abietina mitochondrial RNA virus S2 (GaMRV-S2), Gremmeniella abietina RNA virus MS2 (GaRV-MS2) and Gremmeniella abietina RNA virus L2 (GaRV-L2). The genome of GaMRV-S2 was 2587 base pairs (bp) long and had a very low GC content (31%). Sequence variations occurred at both ends. The genome coded for a putative RNA-dependent RNA polymerase (RdRp) under a mitochondrial translation code. The GaRV-MS2 genome was composed of three dsRNA molecules (1781 bp, 1586 bp and 1186 bp). They coded for a putative RdRp, a coat protein (CP) and a protein with an unknown function, respectively. The GaRV-L2 genome was 5129 bp long and contained two ORFs. The 5′-proximal ORF coded for a putative CP, whereas the 3′-proximal ORF encoded for a putative RdRp. The buoyant density of GaRV-MS2 and GaRV-L2 were 1.37 and 1.42 g/ml, respectively. GaMRV-S2, GaRV-MS2 and GaRV-L2 were closely related to the previously described viruses GaMRV-S1, GaRV-MS1 and GaRV-L1, respectively, and are putative members of the genera Mitovirus, Partitivirus and Totivirus, respectively. This is the first report on the occurrence of viruses of all these different genera in a single fungal isolate. 相似文献
56.
Risto Kerkel? Matthieu Boucher Raihana Zaka Erhe Gao David Harris Jarkko Piuhola Jianliang Song Raisa Serpi Kathleen C. Woulfe Joseph Y. Cheung Eileen O’Leary Joseph V. Bonventre Thomas Force 《CTS Clinical and Translational Science》2011,4(4):236-242
Studies with sPLA2 Group X, and cPLA2α gene‐targeted mice suggest that absence of sPLA2 Group X results in protection from ischemia/reperfusion (I/R) injury in the heart, and absence of cPLA2α Group IV is protective in the brain. Although latter studies might suggest a similar deleterious role for cPLA2α in I/R injury in the heart, the pathophysiology of stroke is intricately related to excitotoxicity and cannot necessarily be extrapolated to the heart. We report here that unlike findings in the brain, cPLA2α(−/−) mice have exaggerated injury following I/R in vivo. In contrast, there is no difference in injury induced by simulated ischemia in cardiomyocytes isolated from cPLA2α(−/−) versus cPLA2α(+/+) mice. This suggests that cPLA2α does not have an important cardiomyocyte autonomous effect on ischemic injury. Prostaglandin E2 (PGE2) levels are significantly reduced in the hearts of the cPLA2α(−/−) mice, and the enhanced injury is ameliorated by treatment with the PGE analog, misoprostol. We demonstrate that cPLA2α is cardioprotective in vivo, and this is likely via cPLA2α‐mediated production of cardioprotective eicosanoids. These studies are the first to identify a protective role for cPLA2 in I/R injury in any organ and raise concerns over long‐term inhibition of cPLA2. Clin Trans Sci 2011; Volume 4: 236–242 相似文献
57.
Al-Sukhun J Lindqvist C Hietanen J Leivo I Penttilä H 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2006,101(3):304-308
Central intraosseous adenoid cystic carcinoma (ACC) of the mandible, formerly known as cylindroma, is a rare neoplasm with only 16 cases reported in the literature. We describe the diagnosis, etiology, and treatment of a central ACC located in the mandibular premolar region. We also review the literature. This case illustrates 2 key facts regarding the diagnosis and etiology of ACC. First, central salivary gland tumors should be considered in the differential diagnosis of cystic lytic lesions in the mandible. Second, even though the origin of this type of tumor is still unknown, the presence of ectopic tissue anterior to the submandibular gland in the submandibular area indicates that this tumor might be made up of ectopic embryogenic inclusions. 相似文献
58.
Event-related potentials were recorded from sleeping newborns to compare amplitudes and latencies of mismatch negativity (MMN) and late discriminative negativity (LDN) in active and quiet sleep stages. MMN and LDN were obtained in response to changes in semi-synthesized vowels from 20 healthy newborn infants. MMN and LDN responses were significant for both active and quiet sleep. The amplitude and latency of MMN or LDN did not differ between the sleep stages. Thus, in contrast to adult studies that show a significant drop in the MMN amplitude and an increase in the MMN latency as the sleep gets deeper, arousal stages do not seem to effect either MMN or LDN characteristics in newborns. These results suggest functional differences between infant and adult sleep. 相似文献
59.
60.
Lauri Peura Kalle Malmioja Kristiina Huttunen Jukka Leppänen Miia Hämäläinen Markus M. Forsberg Jarkko Rautio Krista Laine 《Pharmaceutical research》2013,30(10):2523-2537