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Phosphate metabolites and steroid hormone receptors of benign and malignant breast tumors. A Nuclear Magnetic Resonance study 总被引:1,自引:0,他引:1
Phosphorous 31 (31P) nuclear magnetic resonance (NMR) spectra were recorded from perchloric acid extracts of benign and malignant breast tumors. The spectra were correlated with the histopathologic diagnosis and the steroid receptor status of the tumor. Higher relative content of the lipid-derived metabolite glycerolphosphoethanolamine (GPE), the high-energy nucleoside phosphates (nucleoside-diphosphate [NDP], nucleoside-triphosphate [NTP]), and sugar esters of uridine diphosphate (UDPS) appeared in the carcinomas. Malignant tumors also showed a lower ratio of phosphoethanolamine to phosphocholine (PE/PC) than benign conditions. Lower content of the lipid-derived metabolite glycerolphosphocholine (GPC) and high content of the high-energy compound phosphocreatine (PCr) were associated with malignant tumors having high content of estrogen receptors (ER). High PCr content was also associated in the carcinomas with high progesterone receptors (PgR) content. In the benign tumors NDP and NTP were higher in tumors with high PgR content. The authors suggest that 31P magnetic resonance spectroscopy (MRS) of the breast can provide additional variables to diagnose malignancy, and when combined with magnetic resonance imaging (MRI), invasive procedures may be avoided. It also seems that levels of PCr and GPC obtained from the spectra can serve as markers to hormonal receptor status of breast carcinomas, and may be used in addition to the ER and PgR content to improve prediction of the response to hormonal therapy. Additional development requires in situ MRI and MRS combined studies. 相似文献
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Ketai LH; Williamson MR; Telepak RJ; Levy H; Koster FT; Nolte KB; Allen SE 《Radiology》1994,191(3):665
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S. van Ruth† EBL van Dorst‡ MR Canninga-van Dijk§ MS de Bruin-Weller† 《Journal of the European Academy of Dermatology and Venereology》2007,21(5):678-680
Cutaneous metastasis of vaginal carcinoma is extremely rare. So far, the total number of reported skin metastasis of vaginal carcinoma is only one. We present another case with an unusual manifestation of vagina carcinoma metastasis: skin metastasis presenting as a leg ulcer on the lower leg. 相似文献
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LSECtin interacts with filovirus glycoproteins and the spike protein of SARS coronavirus 总被引:9,自引:0,他引:9
Gramberg T Hofmann H Möller P Lalor PF Marzi A Geier M Krumbiegel M Winkler T Kirchhoff F Adams DH Becker S Münch J Pöhlmann S 《Virology》2005,340(2):265-236
Cellular attachment factors like the C-type lectins DC-SIGN and DC-SIGNR (collectively referred to as DC-SIGN/R) can augment viral infection and might promote viral dissemination in and between hosts. The lectin LSECtin is encoded in the same chromosomal locus as DC-SIGN/R and is coexpressed with DC-SIGNR on sinusoidal endothelial cells in liver and lymphnodes. Here, we show that LSECtin enhances infection driven by filovirus glycoproteins (GP) and the S protein of SARS coronavirus, but does not interact with human immunodeficiency virus type-1 and hepatitis C virus envelope proteins. Ligand binding to LSECtin was inhibited by EGTA but not by mannan, suggesting that LSECtin unlike DC-SIGN/R does not recognize high-mannose glycans on viral GPs. Finally, we demonstrate that LSECtin is N-linked glycosylated and that glycosylation is required for cell surface expression. In summary, we identified LSECtin as an attachment factor that in conjunction with DC-SIGNR might concentrate viral pathogens in liver and lymph nodes. 相似文献