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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
3.
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
4.
Elin Rosen-Wetterholm Oscar Cavefors Björn Redfors Sven-Erik Ricksten Elmir Omerovic Christian L. Polte Jonatan Oras 《Acta anaesthesiologica Scandinavica》2023,67(6):746-754
Introduction
Left ventricular (LV) dysfunction is estimated to occur in 10%–25% of the general intensive care unit (ICU) population and is frequently seen as regional wall motion abnormalities (RWMAs). Although RWMA is mostly attributed to myocardial ischemia or infarction, some studies have suggested that nonischemic RWMA might also be prevalent. We sought to establish that RWMA can be seen in critically ill patients with normal coronary arteries and to explore reasons for RWMA in this population.Methods
In this retrospective study, data from the hospital angiography register and the ICU register were collated between 2012 and 2019. Patients were identified who underwent angiography in conjunction with their ICU stay and had RWMA on echocardiography. Patients were divided into either those with non-obstructed or those with obstructed coronary arteries. Cardiac magnetic resonance imaging (cMRI) examinations were reviewed if they had been performed on patients with non-obstructed coronaries.Results
We identified 53 patients with RWMA and non-obstructed coronary arteries and 204 patients with RWMA and obstructed coronary arteries. Patients with non-obstructed coronary arteries were more often female, younger, and had fewer cardiovascular risk factors. They less commonly had ST elevation, but more frequently had T-wave inversion or serious arrhythmias. Troponin levels were higher in patients with obstructed coronary arteries, but NT-proBNP was similar between the groups. There were no differences in risk-adjusted 90-day mortality between patients with non-obstructed versus obstructed coronary arteries (OR 1.21, [95% CI 0.56–2.64], p = .628). In those with non-obstructed coronary arteries, follow-up echocardiography was available for 38 patients, of whom 30 showed normalization of cardiac function. Of the 14 patients with non-obstructed coronary arteries on whom cMRI was performed, 7 had a tentative diagnosis of Takotsubo syndrome or myocardial stunning; 4 had a myocardial infarction (preexisting in 3 cases); 1 patient had acute myocarditis; 1 patient had post-myocarditis; and 1 patient was diagnosed with dilated cardiomyopathy.Conclusion
RWMA can be seen to occur in critically ill patients in the absence of coronary artery obstruction. Several conditions can cause regional hypokinesia, and cMRI is useful to evaluate the underlying etiology. 相似文献5.
Deitelzweig Steve Luo Xuemei Nguyen Jennifer L. Malhotra Deepa Emir Birol Russ Cristina Li Xiaoyan Lee Theodore C. Ferri Mauricio Wiederkehr Danny Reimbaeva Maya Barnes Geoffrey D. Piazza Gregory 《Journal of thrombosis and thrombolysis》2022,54(4):696-696
Journal of Thrombosis and Thrombolysis - 相似文献
6.
目的探讨非小细胞肺癌组织中微小RNA-139-5p(miR-139-5p)、钙黏蛋白相关蛋白(CTNNB1)表达与患者放射敏感性的关系。方法选取2017年2月—2021年5月于唐山市人民医院放化七科和肿瘤内科就诊的非小细胞肺癌患者癌组织156例为研究对象(研究组);另选取非小细胞肺癌患者86例癌旁正常肺组织作为对照组;根据放射治疗敏感性评定标准,将研究组患者分为进展亚组(n=28)、稳定亚组(n=42)、缓解亚组(n=86)。采用实时荧光定量PCR和免疫组织化学法分别检测肺癌组织、癌旁正常肺组织miR-139-5p、CTNNB1蛋白表达;分析非小细胞肺癌患者癌组织miR-139-5p、CTNNB1蛋白表达与临床病理特征及放射敏感性的关系;Spearman法分析非小细胞肺癌患者癌组织miR-139-5p表达水平与CTNNB1蛋白阳性表达的相关性;Logistic回归分析影响非小细胞肺癌患者放射敏感性的因素。结果研究组癌组织miR-139-5p表达水平低于对照组(t/P=15.204/0.000),CTNNB1蛋白阳性表达率高于对照组(χ2/P=59.206/0.000);miR-139-5p低表达患者中有淋巴结转移、组织分化程度低、TNM分期Ⅳ期患者比例高于miR-139-5p高表达患者(χ2/P=16.006/0.000、24.669/0.000、22.213/0.000);CTNNB1蛋白阴性表达患者中有淋巴结转移、组织分化程度低、TNM分期Ⅳ期患者比例低于CTNNB1蛋白阳性表达患者(χ2/P=21.922/0.000、22.959/0.000、30.108/0.000);非小细胞肺癌患者癌组织miR-139-5p表达水平与CTNNB1蛋白阳性表达呈负相关(r/P=-0.503/0.000);缓解亚组、稳定亚组、进展亚组miR-139-5p低表达率及CTNNB1蛋白阳性表达率依次升高(χ2/P=25.762/0.000、18.721/0.000);CTNNB1蛋白阳性表达、TNM分期高是影响放射敏感性的独立危险因素[OR(95%CI)=2.872(1.546~5.335)、2.732(1.459~5.115)],miR-139-5p高表达是影响放射敏感性的保护因素[OR(95%CI)=0.845(0.750~0.952)]。结论非小细胞肺癌组织中miR-139-5p表达下调、CTNNB1蛋白阳性表达上调,且一定程度上影响放射敏感性。 相似文献
7.
目的探讨“1+X”证书制度下生理学教学改革效果。方法根据职业教育教改精神和文献调研结果,对高职护理专业进行生理学教学改革。结果以岗位需求为量度确定教学目标,以“必需、够用”为原则拟定教学内容,将课程教学与护理过程对接,紧扣“1+X”证书制度,通过职教云平台建设生理学教学资源,融入思政内容,突出技能训练,有效开展基于护理过程的线上线下教学。结论2018级护理专业学生生理学考试成绩与2017级比较,平均分提高4.5分,及格率提高5.7%;参加河南省首届“1+X”老年照护职业技能等级考试的学生,技能考核通过率为100.0%,理论考试通过率为97.8%。 相似文献
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9.
摘要:微管是细胞骨架重要组成成分,是筛选抗肿瘤药物的重要靶标。海洋生态系统的极端环境使海洋生物具备产生独特
化学结构和生理活性天然产物的能力,为新药发现提供了物质基础。本文主要综述了1972-2021年从海洋生物中分离鉴定的成
药性较好的微管去稳定剂抗肿瘤药物的研究进展,总结了活性化合物来源、构效关系,临床研究进展,化学全合成及衍生物的
研究情况等,以期为医药工作者提供新的研究思路,推进靶向微管海洋抗肿瘤药物的发展。 相似文献
10.
目的: 观察木兰脂素对急性鼻窦炎(ARS)大鼠的治疗作用,并探讨其通过高迁移率家族蛋白1/ Toll样受体4/核因子-κB(HMGB1/TLR4/NF-κB)信号通路的调控机制方法: 49只大鼠,随机取9 只作为正常组,40只用鼻窦腔内接种金黄色葡萄球菌法制备ARS模型,36只建模成功大鼠随机分为模型组、木兰脂素低剂量组、木兰脂素高剂量组、阳性组,各9只。木兰脂素低剂量组、木兰脂素高剂量组分别灌胃20、80 mg·kg-1体质量的木兰脂素,模型组和正常组灌胃等体质量溶媒,阳性组灌胃40 mg·kg-1 体质量左氧氟沙星,连续7 d。给药前、末次给药后1 h评估各组鼻窦炎症状评分;测定给药后各组血白细胞(WBC)计数及中性粒细胞占比,观察鼻窦黏膜病理组织学变化,检测鼻腔灌洗液中肿瘤坏死因子-α(TNF-α)、白介素(IL)-6水平及鼻黏膜中HMGB1、TLR4、NF-κB mRNA和蛋白表达情况结果: 给药后,木兰脂素低剂量组、高剂量组、阳性组的急性鼻窦炎症状评分及血WBC计数均低于模型组,但仍高于正常组,且木兰脂素高剂量组及阳性组均低于木兰脂素低剂量组,差异均有统计学意义(P<0.05),而木兰脂素高剂量组与阳性组比较,差异无统计学意义(P>0.05)。与给药前比较,给药后木兰脂素低剂量组、高剂量组及阳性组急性鼻窦炎症状评分均降低(P<0.05),正常组及模型组给药前后无明显差异(P>0.05)。与模型组比较,木兰脂素低剂量组、木兰脂素高剂量组、阳性组中性粒细胞占比均降低,且木兰脂素高剂量组低于木兰脂素低剂量组,阳性组低于木兰脂素高剂量组,差异均有统计学意义(P<0.05),而阳性组与正常组比较,差异无统计学意义(P>0.05)。HE染色显示,模型组大鼠纤毛脱落、缺失、排列紊乱,黏膜上皮破损、变性,黏膜内及黏膜下可见大量炎症细胞浸润; 木兰脂素低剂量组、木兰脂素高剂量组及阳性组上述病理变化均减轻,且木兰脂素高剂量组和阳性组炎症反应减轻更为明显。与模型组比较,木兰脂素低剂量组、木兰脂素高剂量组、阳性组鼻腔灌洗液中 TNF-α、IL-6水平及鼻黏膜中HMGB1、TLR4、NF-κB mRNA和蛋白相对表达量均降低,但仍高于正常组,且木兰脂素高剂量组及阳性组均低于木兰脂素低剂量组,差异均有统计学意义(P<0.05),而木兰脂素高剂量组及阳性组比较,差异无统计学意义(P>0.05)结论: 木兰脂素治疗ARS效果显著,可能通过HMGB1/TLR4/NF-κB信号通路抑制鼻黏膜炎症反应。 相似文献