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991.
Objectives
Efavirenz‐based HIV therapy is associated with breast hypertrophy and gynaecomastia. Here, we tested the hypothesis that efavirenz induces gynaecomastia through direct binding and modulation of the oestrogen receptor (ER).Methods
To determine the effect of efavirenz on growth, the oestrogen‐dependent, ER‐positive breast cancer cell lines MCF‐7, T47D and ZR‐75‐1 were treated with efavirenz under oestrogen‐free conditions in the presence or absence of the anti‐oestrogen ICI 182,780. Cells treated with 17β‐oestradiol in the absence or presence of ICI 182,780 served as positive and negative controls, respectively. Cellular growth was assayed using the crystal violet staining method and an in vitro receptor binding assay was used to measure the ER binding affinity of efavirenz.Results
Efavirenz induced growth in MCF‐7 cells with an estimated effective concentration for half‐maximal growth (EC50) of 15.7 μM. This growth was reversed by ICI 182,780. Further, efavirenz binds directly to the ER [inhibitory concentration for half maximal binding (IC50) of ~52 μM] at a roughly 1000‐fold higher concentration than observed with 17β‐oestradiol.Conclusions
Our data suggest that efavirenz‐induced gynaecomastia may be caused, at least in part, by drug‐induced ER activation in breast tissues. 相似文献992.
993.
van der Krogt Hanneke JM Meskers Carel GM de Groot Jurriaan H Klomp Asbjørn Arendzen J Hans 《Journal of neuroengineering and rehabilitation》2012,9(1):1-7
Background
In rehabilitation, training intensity is usually adapted to optimize the trained system to attain better performance (overload principle). However, in balance rehabilitation, the level of intensity required during training exercises to optimize improvement in balance has rarely been studied, probably due to the difficulty in quantifying the stability level during these exercises. The goal of the present study was to test whether the stabilizing/destabilizing forces model could be used to analyze how stability is challenged during several exergames, that are more and more used in balance rehabilitation, and a dynamic functional task, such as gait.Methods
Seven healthy older adults were evaluated with three-dimensional motion analysis during gait at natural and fast speed, and during three balance exergames (50/50 Challenge, Ski Slalom and Soccer). Mean and extreme values for stabilizing force, destabilizing force and the ratio of the two forces (stability index) were computed from kinematic and kinetic data to determine the mean and least level of dynamic, postural and overall balance stability, respectively.Results
Mean postural stability was lower (lower mean destabilizing force) during the 50/50 Challenge game than during all the other tasks, but peak postural instability moments were less challenging during this game than during any of the other tasks, as shown by the minimum destabilizing force values. Dynamic stability was progressively more challenged (higher mean and maximum stabilizing force) from the 50/50 Challenge to the Soccer and Slalom games, to the natural gait speed task and to the fast gait speed task, increasing the overall stability difficulty (mean and minimum stability index) in the same manner.Conclusions
The stabilizing/destabilizing forces model can be used to rate the level of balance requirements during different tasks such as gait or exergames. The results of our study showed that postural stability did not differ much between the evaluated tasks (except for the 50/50 Challenge), compared to dynamic stability, which was significantly less challenged during the games than during the functional tasks. Games with greater centre of mass displacements and changes in the base of support are likely to stimulate balance control enough to see improvements in balance during dynamic functional tasks, and could be tested in pathological populations with the approach used here. 相似文献994.
Steffan D Bos Nico Lakenberg Ruud van der Breggen Jeanine J Houwing-Duistermaat Margreet Kloppenburg Anton JM de Craen Marian Beekman Ingrid Meulenbelt P Eline Slagboom 《European journal of human genetics : EJHG》2010,18(8):953-959
Cytokines are major immune system regulators. Previously, innate cytokine profiles determined by lipopolysaccharide stimulation were shown to be highly heritable. To identify regulating genes in innate immunity, we analyzed data from a genome-wide linkage scan using microsatellites in osteoarthritis (OA) patients (The GARP study) and their innate cytokine data on interleukin (IL)-1β, IL-1Ra, IL-10 and tumor necrosis factor (TNF)α. A confirmation cohort consisted of the Leiden 85-Plus study. In this study, a linkage analysis was followed by manual selection of candidate genes in linkage regions showing LOD scores over 2.5. An single-nucleotide polymorphism (SNP) gene tagging method was applied to select SNPs on the basis of the highest level of gene tagging and possible functional effects. QTDT was used to identify the SNPs associated with innate cytokine production. Initial association signals were modeled by a linear mixed model. Through these analyses, we identified 10 putative genes involved in the regulation of TNFα. SNP rs6679497 in gene CD53 showed significant association with TNFα levels (P=0.001). No association of this SNP was observed with OA. A novel gene involved in the innate immune response of TNFα is identified. Genetic variation in this gene may have a role in diseases and disorders in which TNFα is closely involved. 相似文献
995.
Corstjens AM van der Horst IC Zijlstra JG Groeneveld AB Zijlstra F Tulleken JE Ligtenberg JJ 《Critical care (London, England)》2006,10(3):216-5
Acute hyperglycaemia has been associated with complications, prolonged intensive care unit and hospital stay, and increased mortality. We made an inventory of the prevalence and prognostic value of hyperglycaemia, and of the effects of glucose control in different groups of critically ill patients. The prevalence of hyperglycaemia in critically ill patients, using stringent criteria, approaches 100%. An unambiguous negative correlation between hyperglycaemia and mortality has been described in various groups of critically ill patients. Although the available evidence remains inconsistent, there appears to be a favourable effect of glucose regulation. This effect on morbidity and mortality depends on patient characteristics. To be able to compare results of future studies involving glucose regulation, better definitions of hyperglycaemia (and consequently of normoglycaemia) and patient populations are needed. 相似文献
996.
J Sven D Mieog Esther M de Kruijf Esther Bastiaannet Peter JK Kuppen Anita Sajet Anton JM de Craen Vincent THBM Smit Cornelis JH van de Velde Gerrit-Jan Liefers 《BMC cancer》2012,12(1):42
Background
The purpose of this study was to compare the expression and the prognostic effect of the breast cancer stem cell marker aldehyde dehydrogenase-1 (ALDH1) in young and elderly breast cancer patients. 相似文献997.
998.
999.
Marieke F van Wier Geertje AM Ari?ns J Caroline Dekkers Ingrid JM Hendriksen Tjabe Smid Willem van Mechelen 《BMC public health》2009,9(1):6
Background
The work setting provides an opportunity to introduce overweight (i.e., Body Mass Index ≥ 25 kg/m2) adults to a weight management programme, but new approaches are needed in this setting. The main purpose of this study was to investigate the effectiveness of lifestyle counselling by phone or e-mail on body weight, in an overweight working population. Secondary purposes were to establish effects on waist circumference and lifestyle behaviours, and to assess which communication method is the most effective. 相似文献1000.
QinJM LiSQ LiuSQ ZengJZ ManXB QiuXH WuMC WangHY 《第二军医大学学报》2005,26(5):514-514
BACKGROUND:SIRPalphal is well known as a negative regulator for cell proliferation through the regulation of the activity of receptor tyrosine kinase with ITAM motif. No investigation to data was undertaken on SIRPalphal involving liver regeneration. MATERIALS AND METHODS: Adult male Sprague-Dawley rats underwent approximately 700% partial hepatectomy (PH) or sham operation (SO). Liver specimens were collected at 2,6,12,24,30,48,72,120,168,and 240 h after PH or SO. 相似文献