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J Imperato-McGinley C Shackleton S Orlic E Stoner 《The Journal of clinical endocrinology and metabolism》1990,70(3):777-782
Male subjects administered the 5 alpha-reductase inhibitor finasteride were studied to determine its effect on C19 and C21 5 alpha-metabolism. Plasma testosterone (T) and 5 alpha-dihydrotestosterone (DHT) were measured and T/DHT ratios determined at doses of 0.2-80 mg. Urinary etiocholanolone (5 beta)/androsterone (5 alpha) ratios and 5 beta/5 alpha metabolite ratios of cortisol, 11 beta-hydroxyandrostenedione, and corticosterone were also measured. The steroid profile was compared to male pseudohermaphrodites with inherited 5 alpha-reductase deficiency who have a global defect in C19 and C21 5 alpha-metabolism. The mean plasma DHT levels were decreased at all doses, resulting in elevated T/DHT ratios. The mean urinary etiocholanolone/androsterone, 11 beta-hydroxyetiocholanolone/11 beta-hydroxyandrosterone, tetrahydrocortisol/allotetrahydrocortisol, and tetrahydrocorticosterone/allotetrahydrocorticosterone ratios were elevated compared to pretreatment levels and placebo control values. The mean ratios appeared to be dose dependent for plasma T/DHT, urinary etiocholanolone/androsterone tetrahydrocorticosterone/allotetrahydrocorticosterone ratios. The mean 11 beta-hydroxyetiocholanolone-hydroxyandrosterone ratio was maximally elevated at the lowest doses. The results indicate that finasteride has a broad steroid spectrum inhibiting C19 and C21 5 alpha-steroid metabolism and affecting hepatic and peripheral 5 alpha-metabolism. These results suggest that a single gene codes for a single 5 alpha-reductase enzyme with affinity for multiple steroid substrates. The steroid profile is strikingly similar to that of male pseudohermaphrodites with inherited 5 alpha-reductase deficiency. 相似文献
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Intermittent PTH administration and mechanical loading are anabolic for periprosthetic cancellous bone
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![点击此处可从《Journal of orthopaedic research》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Matthew J. Grosso Hayden‐William Courtland Xu Yang James P. Sutherland Kirsten Stoner Joseph Nguyen Anna Fahlgren F. Patrick Ross Marjolein C. H. van der Meulen Mathias P. Bostrom 《Journal of orthopaedic research》2015,33(2):163-173
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Overexpression of human cyclin D1 reduces the transforming growth factor beta (TGF-beta) type II receptor and growth inhibition by TGF-beta 1 in an immortalized human esophageal epithelial cell line.
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![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
A Okamoto W Jiang S J Kim E A Spillare G D Stoner I B Weinstein C C Harris 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(24):11576-11580
Cyclin D1 has been implicated in G1 cell cycle progression and is frequently amplified, overtranscribed, and oversynthesized in human tumors, including esophageal carcinomas. To further address the role of cyclin D1 in cell cycle control and tumorigenesis, we have stably transfected the human cyclin D1 in the nontumorigenic esophageal epithelial cell line HET-1A. These transfected cells, which express increased amounts of cyclin D1, have enhanced colony-forming efficiency and saturation density and are resistant to growth inhibition by TGF-beta 1 compared with the parental cell line or a control vector cell clone. The clones which express increased amounts of cyclin D1 exhibited a decrease in the amount of TGF-beta type II receptor, indicating a plausible mechanism for their diminished response to TGF-beta 1. Therefore, deregulated expression of the cyclin D1 gene can modulate the negative growth factor pathway of TGF-beta 1 and may disturb the control of epithelial cell proliferation in esophageal carcinogenesis. 相似文献
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Riley Taitingfong Cinnamon S Bloss Cynthia Triplett Julie Cakici Nanibaa Garrison Shelley Cole Julie A Stoner Lucila Ohno-Machado 《J Am Med Inform Assoc》2020,27(12):1987
BackgroundPrivacy-related concerns can prevent equitable participation in health research by US Indigenous communities. However, studies focused on these communities'' views regarding health data privacy, including systematic reviews, are lacking.MethodsWe conducted a systematic literature review analyzing empirical, US-based studies involving American Indian/Alaska Native (AI/AN) and Native Hawaiian or other Pacific Islander (NHPI) perspectives on health data privacy, which we define as the practice of maintaining the security and confidentiality of an individual’s personal health records and/or biological samples (including data derived from biological specimens, such as personal genetic information), as well as the secure and approved use of those data.ResultsTwenty-one studies involving 3234 AI/AN and NHPI participants were eligible for review. The results of this review suggest that concerns about the privacy of health data are both prevalent and complex in AI/AN and NHPI communities. Many respondents raised concerns about the potential for misuse of their health data, including discrimination or stigma, confidentiality breaches, and undesirable or unknown uses of biological specimens.ConclusionsParticipants cited a variety of individual and community-level concerns about the privacy of their health data, and indicated that these deter their willingness to participate in health research. Future investigations should explore in more depth which health data privacy concerns are most salient to specific AI/AN and NHPI communities, and identify the practices that will make the collection and use of health data more trustworthy and transparent for participants. 相似文献
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Stoner L Erickson ML Young JM Fryer S Sabatier MJ Faulkner J Lambrick DM McCully KK 《Journal of atherosclerosis and thrombosis》2012,19(7):589-600
Flow-mediated dilation (FMD) is the standard tool used to assess endothelial function. The premise behind the standard FMD test is that it serves as an endothelial-dependant nitric oxide bioassay; however, the endothelium may release additional dilatory molecules which contribute to FMD, most notably prostacyclin and endothelial-derived hyperpolarizing factor. The relative importance of these molecules to the dilatory response may vary substantially among individuals, particularly in response to a number of diseased states. This review discusses how each of these molecules may contribute to vasodilation, and considers the circumstances in which they may vary. 相似文献
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