55 research outputs found

    Risk of breast cancer among Norwegian women with visual impairment

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    Experimental studies suggest that melatonin has a protective effect against breast cancer. Exposure to light suppresses melatonin secretion, but to a lesser degree in totally blind persons. Breast cancer was investigated in a cohort of 15 412 Norwegian visually impaired women. The risk among totally blind women was 0.64 (95% CI = 0.21–1.49, 5 cases only), and for those who became blind before age of 65, the SIR was 0.51 (95% CI = 0.11–1.49). Our findings give support to the ‘melatonin hypothesis’. © 2001 Cancer Research Campaign http://www.bjcancer.co

    Antioxidant inhibitors potentiate the cytotoxicity of photodynamic therapy

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    Photodynamic therapy (PDT) is an increasingly popular anticancer treatment that uses photosensitizer, light, and tissue oxygen to generate cytotoxic reactive oxygen species (ROS) within illuminated cells. Acting to counteract ROS-mediated damage are various cellular antioxidant pathways. In this study, we combined PDT with specific antioxidant inhibitors to potentiate PDT cytotoxicity in MCF-7 cancer cells. We used disulphonated aluminium phthalocyanine photosensitizer plus various combinations of the antioxidant inhibitors: diethyl-dithiocarbamate (DDC, a Cu/Zn-SOD inhibitor), 2-Methoxyestradiol (2-ME, a Mn-SOD inhibitor), L-buthionine sulfoximine (BSO, a glutathione synthesis inhibitor) and 3-amino-1,2,4-Triazole (3-AT, a catalase inhibitor). BSO, singly or in combination with other antioxidant inhibitors, significantly potentiated PDT cytotoxicity, corresponding with increased ROS levels and apoptosis. The greatest potentiation of cell death over PDT alone was seen when cells were pre-incubated for 24 hours with 300 ?M BSO plus 10 mM 3-AT (1.62-fold potentiation) or 300 ?M BSO plus 1 ?M 2-ME (1.52-fold), or with a combination of all four inhibitors (300 ?M BSO, 10 mM 3-AT, 1 ?M 2-ME, 10 ?M DDC: 1.4-fold). Because many of these inhibitors have already been clinically tested, this work facilitates future in vivo studies

    Sleep duration and the risk of breast cancer: the Ohsaki Cohort Study

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    In a prospective study of 23 995 Japanese women, short sleep duration was associated with higher risk of breast cancer (143 cases), compared with women who slept 7 h per day, the multivariate hazard ratio of those who slept ⩽6 h per day was 1.62 (95% confidence interval: 1.05–2.50; P for trend=0.03)

    What is known about melatonin, chemotherapy and altered gene expression in breast cancer

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    Melatonin, synthesized in and released from the pineal gland, has been demonstrated by multiple in vivo and in vitro studies to have an oncostatic role in hormone?dependent tumors. Furthermore, several clinical trials point to melatonin as a promising adjuvant molecule to be considered for cancer treatment. In the past few years, evidence of a broader spectrum of action of melatonin as an antitumor agent has arisen; thus, melatonin appears to also have therapeutic effects in several types of hormone?independent cancer, including ovarian, leukemic, pancreatic, gastric and non?small cell lung carcinoma. In the present study, the latest findings regarding melatonin molecular actions when concomitantly administered with either radiotherapy or chemotherapy in cancer were reviewed, with a particular focus on hormone?dependent breast cancer. Finally, the present study discusses which direction should be followed in the next years to definitely clarify whether or not melatonin administration could protect against non?desirable effects (such as altered gene expression and post?translational protein modifications) caused by chemotherapy or radiotherapy treatments. As treatments move towards personalized medicine, comparative gene expression profiling with and without melatonin may be a powerful tool to better understand the antitumor effects of melatonin, the pineal gland hormone

    The great opportunity: Evolutionary applications to medicine and public health

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    Evolutionary biology is an essential basic science for medicine, but few doctors and medical researchers are familiar with its most relevant principles. Most medical schools have geneticists who understand evolution, but few have even one evolutionary biologist to suggest other possible applications. The canyon between evolutionary biology and medicine is wide. The question is whether they offer each other enough to make bridge building worthwhile. What benefits could be expected if evolution were brought fully to bear on the problems of medicine? How would studying medical problems advance evolutionary research? Do doctors need to learn evolution, or is it valuable mainly for researchers? What practical steps will promote the application of evolutionary biology in the areas of medicine where it offers the most? To address these questions, we review current and potential applications of evolutionary biology to medicine and public health. Some evolutionary technologies, such as population genetics, serial transfer production of live vaccines, and phylogenetic analysis, have been widely applied. Other areas, such as infectious disease and aging research, illustrate the dramatic recent progress made possible by evolutionary insights. In still other areas, such as epidemiology, psychiatry, and understanding the regulation of bodily defenses, applying evolutionary principles remains an open opportunity. In addition to the utility of specific applications, an evolutionary perspective fundamentally challenges the prevalent but fundamentally incorrect metaphor of the body as a machine designed by an engineer. Bodies are vulnerable to disease – and remarkably resilient – precisely because they are not machines built from a plan. They are, instead, bundles of compromises shaped by natural selection in small increments to maximize reproduction, not health. Understanding the body as a product of natural selection, not design, offers new research questions and a framework for making medical education more coherent. We conclude with recommendations for actions that would better connect evolutionary biology and medicine in ways that will benefit public health. It is our hope that faculty and students will send this article to their undergraduate and medical school Deans, and that this will initiate discussions about the gap, the great opportunity, and action plans to bring the full power of evolutionary biology to bear on human health problems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90555/1/j.1752-4571.2007.00006.x.pd
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