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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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《Neuro-Chirurgie》2023,69(3):101420
ObjectiveVagus nerve stimulation (VNS) therapy has been used for more than two decades to treat drug resistant epilepsy and depression and most recently received FDA approval for stroke rehabilitation. Expanding indications will renew the interest in the technique and increase the number of surgeons to be trained. The aim of this study was to survey surgeons with substantial expertise on optimal teaching and training approaches.MethodsAnonymous forms comprising 16 questions were sent by e-mail to surgeons with substantial expertise. Statistical analyses were used to compare the answers of the most experienced surgeons (>5 years) with the less experienced ones (<5 years).ResultsFully-completed forms were collected from 57 experts from 20 countries. The placement of the helical coils was deemed to be the most difficult step by 36 (63.2%) experts, and the use of optical magnification during this step was deemed necessary by 39 (68.4%) experts. Vocal cord palsy should be largely avoidable with proper surgical technique according to 44 (77.2%) experts. The teaching tool considered the most useful was mentoring (38, 66.7%). The future of VNS surgery teaching was deemed to be in anatomical workshops (29, 50.9%) and surgical simulation (26, 45.6%). Overall, answers did not vary significantly according to experience.ConclusionsVNS surgery should be mastered by actively participating in dedicated practical training courses and by individual mentoring during actual surgery, which is still the best way to learn. This study highlights the need for a formal training course and possible specific accreditation. 相似文献
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《The Journal of thoracic and cardiovascular surgery》2023,165(1):301-326
ObjectiveThe use of mechanical circulatory support (MCS) in lung transplantation has been steadily increasing over the prior decade, with evolving strategies for incorporating support in the preoperative, intraoperative, and postoperative settings. There is significant practice variability in the use of these techniques, however, and relatively limited data to help establish institutional protocols. The objective of the AATS Clinical Practice Standards Committee (CPSC) expert panel was to review the existing literature and establish recommendations about the use of MCS before, during, and after lung transplantation.MethodsThe AATS CPSC assembled an expert panel of 16 lung transplantation physicians who developed a consensus document of recommendations. The panel was broken into subgroups focused on preoperative, intraoperative, and postoperative support, and each subgroup performed a focused literature review. These subgroups formulated recommendation statements for each subtopic, which were evaluated by the entire group. The statements were then developed via discussion among the panel and refined until consensus was achieved on each statement.ResultsThe expert panel achieved consensus on 36 recommendations for how and when to use MCS in lung transplantation. These recommendations included the use of veno-venous extracorporeal membrane oxygenation (ECMO) as a bridging strategy in the preoperative setting, a preference for central veno-arterial ECMO over traditional cardiopulmonary bypass during the transplantation procedure, and the benefit of supporting selected patients with MCS postoperatively.ConclusionsAchieving optimal results in lung transplantation requires the use of a wide range of strategies. MCS provides an important mechanism for helping these critically ill patients through the peritransplantation period. Despite the complex nature of the decision making process in the treatment of these patients, the expert panel was able to achieve consensus on 36 recommendations. These recommendations should provide guidance for professionals involved in the care of end-stage lung disease patients considered for transplantation. 相似文献
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Mediastinal teratoma rarely causes pericarditis. We report a case of a 22-year-old young female admitted to the emergency department for inspiratory chest pain and fever with severe pericardial effusion, unexepectable the cause of pericarditis was a mediastinal teratoma. 相似文献
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《Journal of cardiac failure》2022,28(7):1185-1201
Sacubitril/valsartan is an angiotensin receptor/neprilysin inhibitor that the Food and Drug Administration has indicated to reduce the risk of cardiovascular hospitalization and death in patients with left ventricular ejection fraction below normal and with no specified ejection-fraction cut-off. However, clinically significant patient groups were excluded or minimally represented in sacubitril/valsartan's pivotal clinical trials. Clinicians often encounter scenarios in which a sacubitril/valsartan off-label use may be beneficial, but limited resources are available to evaluate the efficacy and safety in these patients. This state-of-the-art review describes contemporary literature for sacubitril/valsartan Food and Drug Administration off-label indications to help clinicians assess its appropriateness in these selected, clinically important groups of patients: those with acute decompensated heart failure, acute coronary syndrome, peripartum cardiomyopathy, chemotherapy-induced cardiomyopathy, adult congenital heart disease, cardiomyopathy in dialysis patients, right ventricular failure, or durable left ventricular assist device. 相似文献
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《The Canadian journal of cardiology》2022,38(10):1634-1640
BackgroundDatabases for Congenital Heart Disease (CHD) are effective in delivering accessible datasets ready for statistical inference. Data collection hitherto has, however, been labour and time intensive and has required substantial financial support to ensure sustainability. We propose here creation and piloting of a semiautomated technique for data extraction from clinic letters to populate a clinical database.MethodsPDF formatted clinic letters stored in a local folder, through a series of algorithms, underwent data extraction, preprocessing, and analysis. Specific patient information (diagnoses, diagnostic complexity, interventions, arrhythmia, medications, and demographic data) was processed into text files and structured data tables, used to populate a database. A specific data validation schema was predefined to verify and accommodate the information populating the database. Unsupervised learning in the form of a dimensionality reduction technique was used to project data into 2 dimensions and visualize their intrinsic structure in relation to the diagnosis, medication, intervention, and European Society of Cardiology classification lists of disease complexity. Ninety-three randomly selected letters were reviewed manually for accuracy.ResultsThere were 1409 consecutive outpatient clinic letters used to populate the Scottish Adult Congenital Cardiac Database. Mean patient age was 35.4 years; 47.6% female; with 698 (49.5%) having moderately complex, 369 (26.1%) greatly complex, and 284 (20.1%) mildly complex lesions. Individual diagnoses were successfully extracted in 96.95%, and demographic data were extracted in 100% of letters. Data extraction, database upload, data analysis and visualization took 571 seconds (9.51 minutes). Manual data extraction in the categories of diagnoses, intervention, and medications yielded accuracy of the computer algorithm in 94%, 93%, and 93%, respectively.ConclusionsSemiautomated data extraction from clinic letters into a database can be achieved successfully with a high degree of accuracy and efficiency. 相似文献
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《HPB : the official journal of the International Hepato Pancreato Biliary Association》2022,24(5):645-653
BackgroundMain-duct (MD) intraductal papillary mucinous neoplasm (IPMN) is associated with malignancy risk. There is a lack of consensus on treatment (partial or total pancreatectomy) when the MD is diffusely involved. We sought to characterize the pancreatic remnant fate after partial pancreatectomy for non-invasive diffuse MD-IPMN.MethodsConsecutive patients with partial pancreatectomy for non-invasive MD-IPMN from 2004 to 2016 were analyzed. Diffuse MD-IPMN was defined by preoperative imaging as dilation of the MD in the head of the pancreas more than 5 mm and involving the whole gland.ResultsOf 127 patients with resected non-invasive MD-IPMN, 47 (37%) had diffuse MD involvement. Eleven of 47(23%) patients developed imaging evidence of progression or new cystic disease in the pancreatic remnant. Patients with diffuse MD-IPMN were older (73yrs vs 67yrs, p = 0.009), more likely to receive a pancreaticoduodenectomy (96% vs 56%, p < 0.001) and have high-grade dysplasia (51% vs 31%, p = 0.025) than those with focal MD involvement. Diffuse MD involvement was not associated with shorter PFS following partial pancreatectomy (p = 0.613).ConclusionPartial pancreatectomy is an appropriate surgical approach for diffuse MD-IPMN, and is not associated with earlier progression after surgery as compared to partial pancreatectomy for focal dilation. 相似文献