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BackgroundPancreatoduodenectomies at high risk for clinically relevant pancreatic fistula are uncommon, yet intimidating, situations. In such scenarios, the impact of individual surgeon experience on outcomes is poorly understood.MethodsThe fistula risk score was applied to identify high-risk patients (fistula risk score 7–10) from 7,706 pancreatoduodenectomies performed at 18 international institutions (2003–2020). For each case, surgeon pancreatoduodenectomy career volume and years of practice were linked to intraoperative fistula mitigation strategy adoption and outcomes. Consequently, best operative approaches for clinically relevant pancreatic fistula prevention and best performer profiles were identified through multivariable analysis models.ResultsEight hundred and thirty high-risk pancreatoduodenectomies, performed by 64 surgeons, displayed an overall clinically relevant pancreatic fistula rate of 33.7%. Clinically relevant pancreatic fistula rates decreased with escalating surgeon career pancreatoduodenectomy (–49.7%) and career length (–41.2%; both P < .001), as did transfusion and reoperation rates, postoperative morbidity index, and duration of stay. Great experience (≥400 pancreatoduodenectomies performed or ≥21-year-long career) was a significant predictor of clinically relevant pancreatic fistula prevention (odds ratio 0.52, 95% confidence interval 0.35–0.76) and was more often associated with pancreatojejunostomy reconstruction and prophylactic octreotide omission, which were both independently associated with clinically relevant pancreatic fistula reduction. A risk-adjusted performance analysis also correlated with experience. Moreover, minimizing blood loss (≤400 mL) significantly contributed to clinically relevant pancreatic fistula prevention (odds ratio 0.40, 95% confidence interval 0.22–0.74).ConclusionSurgeon experience is a key contributor to achieve better outcomes after high-risk pancreatoduodenectomy. Surgeons can improve their performance in these challenging situations by employing pancreatojejunostomy reconstruction, omitting prophylactic octreotide, and minimizing blood loss.  相似文献   
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We, herein, report the first use of a Magmaris® magnesium‐based vascular scaffold for native aortic coarctation in a 1,980 g infant with multiple malformations. Due to the low body weight, complex illness, and clinical instability, it was decided to delay surgical correction. After insufficient results had been obtained by balloon angioplasty, Magmaris® implantation was chosen to bridge the patient to surgery by stabilizing left ventricular function and to allow for sufficient growth. Due to significant early stent restenosis and complete loss of radial force, the patient required balloon reangioplasty only 21 days after Magmaris® implantation and early surgical correction. In addition, high systemic sirolimus levels were detected 48 hr after the intervention (5 ng/mL). Although the bioresorbable scaffold was successfully used as a short‐term bridge‐to‐surgery in our case, due to significant early stent failure (loss of radial force), this approach does not seem promising for long‐term bridging of infants with aortic coarctation. In addition, the consequences of sirolimus‐induced systemic immunosuppression may further limit the applicability of Magmaris® scaffolds in infants with congenital heart disease.  相似文献   
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Background The rate of preterm births in Germany is 8.6%, which is very high compared to other European countries. As preterm birth contributes significantly to perinatal morbidity and mortality rates, the existing prevention strategies need to be optimized and expanded further. About ⅔ of all women with preterm birth have preterm labor or premature rupture of membranes. They are bracketed together under the term “spontaneous preterm birth” as opposed to iatrogenic preterm birth, for example as a consequence of preeclampsia or fetal growth retardation. Recent studies suggest that low-dose aspirin does not just reduce the rate of iatrogenic preterm births but can also further reduce the rate of spontaneous preterm births. This review article presents the current state of knowledge. Method A selective literature search up until April 2020 was done in PubMed, using the terms “randomized trial”, “randomized study”, “spontaneous preterm birth”, and “aspirin”. Results Secondary analyses of prospective randomized studies on the prevention of preeclampsia with low-dose aspirin show that this intervention also significantly reduced the rate of spontaneous preterm births in both high-risk and low-risk patient populations. The results of the ASPIRIN trial, a prospective, randomized, double-blinded multicenter study carried out in six developing countries, also point in this direction, with the figures showing that the daily administration of 81 mg aspirin starting before 14 weeks of gestation lowered the preterm birth rate of nulliparous women without prior medical conditions by around 11% (11.6 vs. 13.1%; RR 0.89; 95% CI: 0.81 – 0.98, p = 0.012). Conclusion Further studies on this issue are urgently needed. If these confirm the currently available results, then it would be worth discussing whether general aspirin prophylaxis for all pregnant women starting at the latest in 12 weeks of gestation is indicated. Key words: spontaneous preterm birth, iatrogenic preterm birth, prevention, preeclampsia, aspirin  相似文献   
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Iron accumulation in the CNS is associated with many neurological diseases via amplification of inflammation and neurodegeneration. However, experimental studies on iron overload are challenging, since rodents hardly accumulate brain iron in contrast to humans. Here, we studied LEWzizi rats, which present with elevated CNS iron loads, aiming to characterise choroid plexus, ependymal, CSF and CNS parenchymal iron loads in conjunction with altered blood iron parameters and, thus, signifying non‐classical entry sites for iron into the CNS. Non‐haem iron in formalin‐fixed paraffin‐embedded tissue was detected via DAB‐enhanced Turnbull Blue stainings. CSF iron levels were determined via atomic absorption spectroscopy. Ferroportin and aquaporin‐1 expression was visualised using immunohistochemistry. The analysis of red blood cell indices and serum/plasma parameters was based on automated measurements; the fragility of red blood cells was manually determined by the osmotic challenge. Compared with wild‐type animals, LEWzizi rats showed strongly increased iron accumulation in choroid plexus epithelial cells as well as in ependymal cells of the ventricle lining. Concurrently, red blood cell macrocytosis, low‐grade haemolysis and significant haemoglobin liberation from red blood cells were apparent in the peripheral blood of LEWzizi rats. Interestingly, elevated iron accumulation was also evident in kidney proximal tubules, which share similarities with the blood–CSF barrier. Our data underscore the importance of iron gateways into the CNS other than the classical route across microvessels in the CNS parenchyma. Our findings of pronounced choroid plexus iron overload in conjunction with peripheral iron overload and increased RBC fragility in LEWzizi rats may be seminal for future studies of human diseases, in which similar constellations are found.  相似文献   
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The aim of this study was to develop a new breast density classification system for dedicated breast computed tomography (BCT) based on lesion detectability analogous to the ACR BI-RADS breast density scale for mammography, and to evaluate its interrater reliability.In this retrospective study, 1454 BCT examinations without contrast media were screened for suitability. Excluding datasets without additional ultrasound and exams without any detected lesions resulted in 114 BCT examinations. Based on lesion detectability, an atlas-based BCT density (BCTD) classification system of breast parenchyma was defined using 4 categories. Interrater reliability was examined in 40 BCT datasets between 3 experienced radiologists.Among the included lesions were 63 cysts (55%), 18 fibroadenomas (16%), 7 lesions of fatty necrosis (6%), and 6 breast cancers (5%) with a median diameter of 11 mm. X-ray absorption was identical between lesions and breast tissue; therefore, the lack of fatty septae was identified as the most important criteria for the presence of lesions in glandular tissue. Applying a lesion diameter of 10 mm as desired cut-off for the recommendation of an additional ultrasound, an atlas of 4 BCTD categories was defined resulting in a distribution of 17.5% for density A, 39.5% (B), 31.6% (C), and 11.4% (D) with an intraclass correlation coefficient (ICC) among 3 readers of 0.85 to 0.87.We propose a dedicated atlas-based BCTD classification system, which is calibrated to lesion detectability. The new classification system exhibits a high interrater reliability and may be used for the decision whether additional ultrasound is recommended.  相似文献   
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