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Marike Gabrielson Mattias Hammarström Magnus Bäcklund Jenny Bergqvist Kristina Lång Ann H Rosendahl Signe Borgquist Roxanna Hellgren Kamila Czene Per Hall 《International journal of cancer. Journal international du cancer》2023,152(11):2362-2372
Tamoxifen prevents recurrence of breast cancer and is suggested for preventive risk-reducing therapy. Tamoxifen reduces mammographic density, a proxy for therapy response, but little is known about its effects in remodelling normal breast tissue. Our study, a substudy within the double-blinded dose-determination trial KARISMA, investigated tamoxifen-specific changes in breast tissue composition and histological markers in healthy women. We included 83 healthy women randomised to 6 months daily intake of 20, 10, 5, 2.5, 1 mg of tamoxifen or placebo. The groups were combined to “no dose” (0-1 mg), “low-dose” (2.5-5 mg) or “high-dose” (10-20 mg) of tamoxifen. Ultrasound-guided biopsies were collected before and after tamoxifen exposure. In each biopsy, epithelial, stromal and adipose tissues was quantified, and expression of epithelial and stromal Ki67, oestrogen receptor (ER) and progesterone receptor (PR) analysed. Mammographic density using STRATUS was measured at baseline and end-of-tamoxifen-exposure. We found that different doses of tamoxifen reduced mammographic density and glandular-epithelial area in premenopausal women and associated with reduced epithelium and increased adipose tissue. High-dose tamoxifen also decreased epithelial ER and PR expressions in premenopausal women. Premenopausal women with the greatest reduction in proliferation also had the greatest epithelial reduction. In postmenopausal women, high-dose tamoxifen decreased the epithelial area with no measurable density decrease. Tamoxifen at both low and high doses influences breast tissue composition and expression of histological markers in the normal breast. Our findings connect epithelial proliferation with tissue remodelling in premenopausal women and provide novel insights to understanding biological mechanisms of primary prevention with tamoxifen. 相似文献
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Kara S. Tanaka MD Veronica R. Andaya BA Steven W. Thorpe MD Kenneth R. Gundle MD James B. Hayden MD Yee-Cheen Duong MD Raffi S. Avedian MD David G. Mohler MD Lee J. Morse MD Melissa N. Zimel MD Richard J. O'Donnell MD Andrew Fang MD Robert Lor Randall MD Tina H. Tran BS Christin New BA Rosanna L. Wustrack MD other members of Study Group FORCE 《Journal of surgical oncology》2023,127(1):148-158
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S. Liu A. E. Patanwala J. M. Naylor N. Levy R. Knaggs J. A. Stevens B. Bugeja D. Begley K. E. Khor E. Lau R. Allen S. Adie J. Penm 《Anaesthesia》2023,78(10):1237-1248
Modified-release opioids are often prescribed for the management of moderate to severe acute pain following total hip and knee arthroplasty, despite recommendations against their use due to increasing concerns regarding harm. The primary objective of this multicentre study was to examine the impact of modified-release opioid use on the incidence of opioid-related adverse events compared with immediate-release opioid use, among adult inpatients following total hip or knee arthroplasty. Data for total hip and knee arthroplasty inpatients receiving an opioid analgesic for postoperative analgesia during hospitalisation were collected from electronic medical records of three tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events during hospital admission. Patients who received modified with or without immediate-release opioids were matched to those receiving immediate-release opioids only (1:1) using nearest neighbour propensity score matching with patient and clinical characteristics as covariates. This included total opioid dose received. In the matched cohorts, patients given modified-release opioids (n = 347) experienced a higher incidence of opioid-related adverse events overall, compared with those given immediate-release opioids only (20.5%, 71/347 vs. 12.7%, 44/347; difference in proportions 7.8% [95%CI 2.3–13.3%]). Modified-release opioid use was associated with an increased risk of harm when used for acute pain during hospitalisation after total hip or knee arthroplasty. 相似文献
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【目的】 探讨医学期刊编辑处理生物医学研究伦理问题的方式,为推动确立医学期刊伦理审查规范提供参考。【方法】 通过问卷星向国内医学期刊编辑发放调查问卷,对审稿时和论文出版后处理医学伦理相关问题的方式展开调研。【结果】 共回收问卷230份。调查显示:在审稿阶段,在保护患者隐私方面,英文期刊、中英双语期刊的编辑更注重要求作者提供授权同意相关证明材料;中、英文期刊以及中英双语期刊的编辑对涉及人体试验伦理问题的处理方式都比较规范。但是,对于研究是否获得患者知情同意、动物实验研究是否经过伦理委员会审查、回顾性研究是否需要伦理审查、涉及人的研究是否在临床试验注册中心注册等问题,编辑还需要进一步重视。在论文出版后,编辑发现的医学伦理问题主要是“涉及人的研究未说明是否经过伦理委员会审查”。对论文出版后发现的没有保护患者隐私和没有在临床试验注册中心注册的问题,大部分期刊缺乏相关处理方案。【结论】 编辑应加强对论文知情同意、动物实验伦理、回顾性研究伦理的审查,并审查涉及人的研究是否在临床试验注册中心注册,以推动我国医学期刊的高质量发展。 相似文献
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Jos B. Poell Leon J. Wils Arjen Brink Ralf Dietrich Christine Krieg Eunike Velleuer Ilkay Evren Elisabeth R. Brouns Jan G. de Visscher Elisabeth Bloemena Bauke Ylstra Ruud H. Brakenhoff 《International journal of cancer. Journal international du cancer》2023,152(2):227-238
Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient. 相似文献
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目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。 相似文献
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Boffa Joseph W. Tock Jamie L. Morabito Danielle M. Schmidt Norman B. 《Cognitive therapy and research》2022,46(5):1016-1029
Cognitive Therapy and Research - Despite interest in psychological inflexibility as a marker of suicide risk, no measure of psychological inflexibility specific to SI exists. The present study... 相似文献
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