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1.
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
2.
《Pancreatology》2022,22(8):1175-1180
BackgroundHepatic steatosis has been described as a common finding in adults following total pancreatectomy with islet autotransplantation (TPIAT) but it is unknown if this occurs in children and adolescents.ObjectivesTo define the frequency of post-TPIAT hepatic steatosis in a sample of children and adolescents and to identify clinical predictors of incident steatosis post-TPIAT.MethodsIn this prospective study, consecutive participants at least 1-month post-TPIAT underwent a liver MRI with proton density fat fraction (PDFF) and blood draw at our pediatric academic medical center between April 2021 and January 2022. Comparison clinical pre-TPIAT liver MRI or ultrasound and insulin use and graft function data were extracted from the medical record. T-tests were used for the comparison of means across continuous variables between participants with and without post-TPIAT steatosis.ResultsA total of 20 participants (mean: 13 ± 4 years; 12 female) were evaluated. Mean liver PDFF at research MRI was 7.4 ± 6.2% (range: 2–25%). Seven participants (35%) had categorical hepatic steatosis (PDFF>5%) post-TPIAT, five of whom had pre-TPIAT steatosis, reflecting a 13% (2/15; 95% CI: 2–40%) incidence of post-TPIAT steatosis. Participant characteristics were not significantly different between subgroups with and without post-TPIAT steatosis. Mean PDFF at research MRI was not different between graft function subgroups (7.5% optimal/good vs. 7.3% marginal/failure; p = .96).ConclusionOur study shows a moderate prevalence but low incidence of hepatic steatosis in a small sample of children and adolescents post-TPIAT. This study raises questions about a causal relationship between TPIAT and hepatic steatosis. 相似文献
3.
目的通过测量锁骨钩钢板内固定术后患者影像学资料,分析发生肩峰骨侵蚀的原因是否与钢板钩-肩峰匹配度相关。
方法回顾性分析2015年8月1日至2018年8月31日期间在上海市浦东医院骨科就诊的210例患者的影像学资料,210例患者均因肩锁关节脱位或锁骨远端骨折行锁骨钩钢板内固定治疗,其中男110例、女100例;年龄24~76岁,平均(44.60±8.75)岁;肩锁关节脱位70例,锁骨远端骨折140例。测量术后及终末随访患者肩锁关节正位X线片相关数据,按锁骨钩钢板术后是否发生肩峰骨侵蚀,将纳入患者分为3组:无骨侵蚀组(A组)、伴钢板钩移位骨侵蚀组(B组)、不伴移位的骨侵蚀组(C组),分别测量钢板钩-肩峰的匹配度(β),统计分析术后发生肩峰骨侵蚀与钢板钩-肩峰匹配度之间的关系。
结果纳入研究的210例患者术后随访24~64周,平均(32.0±6.5)周。A组患者115例,B组患者54例,C组患者41例。A组匹配度β(3.72±0.48)mm与B组β1(6.91±0.84)mm比较差异有统计学意义(P<0.05);A组匹配度β(3.72±0.48)mm与C组β2(5.88±0.65)mm比较差异有统计学意义(P<0.05);B组匹配度β1(6.91±0.84)mm与C组β2(5.88±0.65)mm比较差异有统计学意义(P<0.05)。
结论锁骨钩钢板内固定术后是否发生肩峰骨侵蚀与钢板钩-肩峰匹配度β存在明显相关性,钢板钩与肩峰之间的匹配度越好,β值越小,发生肩峰骨侵蚀的可能性更小。 相似文献
4.
5.
阿尔茨海默病是一种进行性且不可逆转的神经系统疾病,由于视网膜和中枢神经系统有相似的胚胎起源和生理特征,眼科检查可提供简单无创的诊断方法。光学相干断层扫描技术(OCT)能够精确地测量视网膜各个组织层面的厚度,以评估视网膜的退行性改变,光学相干断层扫描血管成像(OCTA)可以提供高分辨率三维成像,从而更直观地检测视网膜血管的变化,间接地反映脑神经元和血管的病理特征。就OCT测量视网膜厚度及OCTA测量视网膜血流变化在阿尔茨海默病诊断中的研究进展进行综述。 相似文献
6.
BackgroundThe Journal of Oral Biosciences is devoted to advancing and disseminating fundamental knowledge concerning every aspect of oral biosciences.HighlightThis review features review articles in the fields of “Extracellular Vesicles,” “Propolis,” “Odontogenic Tumors,” “Periodontitis,” “Periodontium,” “Flavonoids,” “Lactoferrin,” “Dental Plaque,” “Anatomy,” “Induced Pluripotent Stem Cells,” “Bone Cell Biology,” “Dysgeusia,” “Dental Caries,” and “Dental Pulp Cavity,” in addition to the review article by the winners of the “Lion Award” (“Sox9 function in salivary gland development”) presented by the Japanese Association for Oral Biology.ConclusionThese reviews in the Journal of Oral Biosciences have inspired its readers to broaden their knowledge regarding various aspects of oral biosciences. The current editorial review introduces these exciting review articles. 相似文献
7.
目的 测定儿童1型糖尿病(T1DM)患者骨密度(BMD),分析探讨骨密度变化的影响因素。方法 选取于2018年1月—2021年6月于我院收治的儿童1型糖尿病患者76例,收集性别、年龄、发病年龄、身高、体重、BMI、病程等基本资料,检测空腹血糖、空腹C肽、糖化血红蛋白(HbA1c)、血碳酸氢根(HCO3-)、血清碱性磷酸酶(ALP),应用双能X线吸收测定法测定骨密度,获取Z值。结果 76例儿童1型糖尿病患者骨密度Z值为-0.93±2.14。HbA1c、病程与骨密度Z值呈负相关,差异具有统计学意义(分别B=-0.334,P<0.001;B=-0.191,P=0.017)。结论 儿童1型糖尿病患者骨密度低于健康儿童,血糖控制不良、病程长是1型糖尿病儿童骨密度减低的危险因素。 相似文献
8.
目的 探讨艾拉莫德联合甲氨蝶呤治疗类风湿性关节炎(RA)的临床效果及对患者骨代谢的影响。方法 将我院收治的86例RA患者随机分为两组各43例。对照组采用甲氨蝶呤治疗,观察组采用艾拉莫德联合甲氨蝶呤治疗。比较两组的临床疗效、骨代谢指标(β-CTX、 TPINP、 N-MID)及不良反应发生情况。结果 观察组治疗总有效率为95.35%,明显高于对照组的81.40%(P<0.05)。治疗后,两组的β-CTX水平降低, TPINP、 N-MID水平升高(P<0.05);观察组的β-CTX水平明显低于对照组, TPINP、 N-MID水平高于对照组(P<0.05)。两组的不良反应发生率(9.30%vs. 6.98%)比较差异无统计学意义(P>0.05)。结论 艾拉莫德联合甲氨蝶呤治疗RA效果显著,可有效改善患者的骨代谢,且安全性较高。 相似文献
9.
《Journal of vascular and interventional radiology : JVIR》2022,33(10):1213-1221.e5
PurposeTo investigate the pharmacokinetics (PK) and early effects of conventional transarterial chemoembolization (TACE) using sorafenib and doxorubicin on tumor necrosis, hypoxia markers, and angiogenesis in a rabbit VX2 liver tumor model.Materials and MethodsVX2 tumor-laden New Zealand White rabbits (N = 16) were divided into 2 groups: 1 group was treated with hepatic arterial administration of ethiodized oil and doxorubicin emulsion (DOX-TACE), and the other group was treated with ethiodized oil, sorafenib, and doxorubicin emulsion (SORA-DOX-TACE). Animals were killed within 3 days of the procedure. Levels of sorafenib and doxorubicin were measured in blood, tumor, and adjacent liver using mass spectrometry. Tumor necrosis was determined by histopathological examination. Intratumoral hypoxia-inducible factor (HIF) 1α, vascular endothelial growth factor (VEGF), and microvessel density (MVD) were determined by immunohistochemistry.ResultsThe median intratumoral concentration of sorafenib in the SORA-DOX-TACE group was 17.7 μg/mL (interquartile range [IQR], 7.42–33.5 μg/mL), and its maximal plasma concentration (Cmax) was 0.164 μg/mL (IQR, 0.0798–0.528 μg/mL). The intratumoral concentration and Cmax of doxorubicin were similar between the groups: 4.08 μg/mL (IQR, 3.18–4.79 μg/mL) and 0.677 μg/mL (IQR, 0.315–1.23 μg/mL), respectively, in the DOX-TACE group and 1.68 μg/mL (IQR, 0.795–4.08 μg/mL) and 0.298 μg/mL (IQR, 0.241–0.64 μg/mL), respectively, in the SORA-DOX-TACE group. HIF-1α expression was increased in the SORA-DOX-TACE group than in the DOX-TACE group. Tumor volume, tumor necrosis, VEGF expression, and MVD were similar between the 2 groups.ConclusionsThe addition of sorafenib to DOX-TACE delivered to VX2 liver tumors resulted in high intratumoral and low systemic concentrations of sorafenib without altering the PK of doxorubicin. 相似文献
10.