An Approach for Predicting the Low-Cycle-Fatigue Crack Initiation Life of Ultrafine-Grained Aluminum Alloy Considering Inhomogeneous Deformation and Microscale Multiaxial Strain

In this paper, a low-cycle-fatigue (LCF) crack initiation life prediction approach that explicitly distinguishes nucleation and small crack propagation regimes is presented for ultrafine-grained (UFG) aluminum alloy by introducing two fatigue indicator parameters (FIPs) at the grain level. These two characterization parameters, the deformation inhomogeneity measured by the standard deviation of the dot product of normal stress and longitudinal strain and the microscale multiaxial strain considering the non-proportional cyclic additional hardening and mean strain effect, were proposed and respectively regarded as the driving forces for fatigue nucleation and small crack propagation. Then, the nucleation and small crack propagation lives were predicted by correlating these FIPs with statistical variables and cyclic J-integrals, respectively. By constructing a microstructure-based 3D polycrystalline finite element model with a free surface, a crystal plasticity finite element-based numerical simulation was carried out to quantify FIPs and clarify the role of crystallographic anisotropy in fatigue crack initiation. The numerical results reveal the following: (1) Nucleation is prone to occur on the surface of a material as a result of it having a higher inhomogeneous deformation than the interior of the material. (2) Compared with the experimental data, the LCF initiation life of UFG 6061 aluminum alloy could be predicted using the new parameters as FIPs. (3) The predicted results confirm the importance of considering the fatigue behavior of nucleation and small crack propagation with different deformation mechanisms for improving the fatigue crack initiation life prediction accuracy.     

亚急性皮肤型红斑狼疮伴纵行黑甲一例

患者,男,35岁。因躯干、四肢红斑、丘疹8个月于2015年5月20日就诊我科。8个月前患者无明显诱因躯干、四肢出现肿胀性红斑、花生米大红色丘疹、结节,部分皮疹排列成环形,伴瘙痒。皮疹以前胸及上肢为重,半月内可消退,但反复新发,于日晒及饮酒后加重。曾反复就诊于当地医院,服抗组胺药治疗,病情无明显改善。     

获得性淋巴管扩张症

报告1例获得性淋巴管扩张症。患者女,63岁。因左上臂近端内侧无症状小水疱5年就诊。10年前,患者因患左乳腺癌行左乳切除术。皮损组织病理检查示真皮有许多扩张的管腔,管腔内未见红细胞。免疫组化检查示管腔内的扁平内皮细胞CD31和D2—40（淋巴管特异性标志抗体）阳性,而CD34和FⅧ阴性。符合获得性淋巴管扩张症的诊断。     

Risk Factors for Long-Term Mortality and Progressive Chronic Kidney Disease Associated With Acute Kidney Injury After Cardiac Surgery

The aim of the study was to evaluate risk factors for long-term mortality and progressive chronic kidney disease (CKD) after cardiac surgery in patients with normal preoperative renal function and postoperative acute kidney injury (AKI). From April 2009 to December 2012, we prospectively enrolled 3245 cardiac surgery patients of our hospital. The primary endpoints included survival rates and the secondary endpoint was the incidence of progressive chronic kidney disease (CKD) in a follow-up period of 2 years. Acute kidney injury was staged by KDIGO classification. Progressive CKD was defined as GFR ≤ 30 mL/min/1.73 m² or end-stage renal disease (ESRD) (starting renal replacement therapy or renal transplantation).The AKI incidence was 39.9% (n = 1295). The 1 and 2 year overall survival (OS) rates of AKI patients were significantly lower than that for non-AKI patients (85.9% and 82.3% vs 98.1% and 93.7%, P < 0.001), even after complete recovery of renal function during 2 years after intervention (P < 0.001). The 2-year overall survival (OS) rates of patients with AKI stage 1, 2, and 3 were 89.9%, 78.6%, and 61.4% (P < 0.001), respectively. Multivariate Cox regression analysis of factors for 2-year survival rates revealed that besides age (P < 0.001), chronic cardiac failure (P < 0.001), diabetes (P < 0.001), cardiopulmonary bypass time (P < 0.01), and length of intensive care unit (ICU) stay (P = 0.004), AKI was a significant risk factor for reducing 2-year survival rates even after complete recovery of renal function (P < 0.001). The accumulated progressive CKD prevalence was significantly higher in AKI than in non-AKI patients (6.8% vs 0.2%, P < 0.001) in the 2 years after surgery. Even with complete recovery of renal function at discharge, AKI was still a risk factor for accumulated progressive CKD (RR 1.92, 95% CI 1.37–2.69).The 2-year mortality and progressive CKD incidence even after complete recovery of renal function were significantly increased in cardiac surgery patients with postoperative AKI.     

Erosive pustular dermatosis of the scalp in an adolescent with near‐total hair regrowth: Case report and review of the literature

Erosive pustular dermatosis of the scalp (EPDS) is an uncommon chronic inflammatory response to scalp trauma that usually resolves with cicatricial alopecia. It most commonly affects elderly patients with a history of actinic damage. Herein, we describe a 16‐year‐old girl with acrofacial dysostosis type 1 presenting after surgery with crusting purulent scalp lesions, whose clinical presentation and histopathologic findings were consistent with EPDS. A review of the literature on EPDS in children is also detailed.     

Promoter Methylation of LEP and LEPR before and after Bariatric Surgery: A Cross-Sectional Study

IntroductionDNA methylation constitutes one important epigenetic mechanism that regulates gene expression in human cells. With regard to obesity, bariatric surgery-induced weight loss has been associated with promoter methylation changes in several genes. Hyperleptinemia is a characteristic feature of obesity. The underlying regulating mechanisms have not yet been completely elucidated.MethodsWe investigated the methylation of the promoters of the leptin gene (LEP) and the leptin receptor gene (LEPR) as well as leptin expression in pre- and postbariatric surgery patients using a comparative cross-sectional design.ResultsOur results revealed significantly higher LEP promoter methylation patterns in prebariatric surgery patients compared to postoperatively. DNA methylation of the LEPR promoter was significantly higher in the postoperative group. Moreover, we found significantly higher leptin serum levels in patients before the bariatric surgery than afterwards.DiscussionThese findings strengthen the suggestion that there is an association between LEP expression and LEP methylation in obesity. We suggest that the epigenetic profile of LEP might be influenced by leptin serum levels in the form of a regulating feedback mechanism.     

超声内镜引导基因重组人溶瘤腺病毒植入治疗晚期胰腺癌初步研究

目的 探讨EUS引导基因重组人5型腺病毒H101植入联合吉西他滨治疗晚期胰腺癌的安全性及其临床价值.方法 自2007年5月-12月,共6例晚期胰腺癌患者于EUS引导下将H101分3点注入瘤体内,第2、9、16天行吉西他滨全身化疗,1个月为1个周期,共2个周期.采用计算机三维重建及灌注成傢技术观察肿瘤体积改变及瘤体内部血流灌注情况.记录.临床指标的改善、不良反应及并发症等.结果 6例患者均按预定计划完成治疗,其中5例肿瘤体积较治疗前不同程度缩小(18.21%-38.65%),但差异无统计学意义(P=0.078).1例肝脏转移灶明显缩小.灌注成像显示治疗后2周平均通过时间较治疗前明显延长(P=0.049),血流量、血容量及表面通透性呈有利改变.2例卡诺夫斯基量表评分提高,3例疼痛评分明显下降.3例患者已死亡(生存期分别为2.5、2.5、3个月),3例仍存活患者生存期分别为3、5、10个月.不良反应主要为发热和流感样症状,1例患者发生轻症胰腺炎.结论 结果初步提示EUS引导基因重组人5型腺病毒植入治疗晚期胰腺癌临床安全、可行,与吉西他滨联合具有潜在缩小肿瘤体积、破坏肿瘤血供及改善患者生存质量的作用.     

A longitudinal study of age‐ and gender‐related annual rate of volume changes in regional gray matter in healthy adults

The aim of this study was to analyze correlations among the annual rate of gray matter volume change, age, gender, and cerebrovascular risk factors in 381 healthy community‐dwelling subjects with a large age range by applying a longitudinal design over 6 years using brain magnetic resonance images (MRIs). Brain MRI data were processed with voxel‐based morphometry using a custom template by applying diffeomorphic anatomical registration using the exponentiated lie algebra procedure. The annual rate of regional gray matter volume change showed significant positive correlations with age in several regions, including the bilateral temporal pole, caudate nucleus, ventral and dorsolateral prefrontal cortices, insula, hippocampus, and temporoparietal cortex, whereas significant negative correlations with age were observed in several regions including the bilateral cingulate gyri and anterior lobe of the cerebellum. Additionally, a significant age‐by‐gender interaction was found for the annual rate of regional gray matter volume change in the bilateral hippocampus. No significant correlations were observed between the annual rate of regional gray matter volume change and body mass index or systolic blood pressure. A significant positive correlation between the annual rate of gray matter volume change and age indicates that the region shows not linear but accelerated gray matter loss with age. Therefore, evaluating the annual rate of the gray matter volume change with age in healthy subjects is important in understanding how gray matter volume changes with aging in each brain region and in anticipating what cognitive functions are likely to show accelerated decline with aging. Hum Brain Mapp 34:2292–2301, 2013. © 2012 Wiley Periodicals, Inc.     

Perceiving nonverbal behavior: Neural correlates of processing movement fluency and contingency in dyadic interactions

Despite the fact that nonverbal dyadic social interactions are abundant in the environment, the neural mechanisms underlying their processing are not yet fully understood. Research in the field of social neuroscience has suggested that two neural networks appear to be involved in social understanding: (1) the action observation network (AON) and (2) the social neural network (SNN). The aim of this study was to determine the differential contributions of the AON and the SNN to the processing of nonverbal behavior as observed in dyadic social interactions. To this end, we used short computer animation sequences displaying dyadic social interactions between two virtual characters and systematically manipulated two key features of movement activity, which are known to influence the perception of meaning in nonverbal stimuli: (1) movement fluency and (2) contingency of movement patterns. A group of 21 male participants rated the “naturalness” of the observed scenes on a four‐point scale while undergoing fMRI. Behavioral results showed that both fluency and contingency significantly influenced the “naturalness” experience of the presented animations. Neurally, the AON was preferentially engaged when processing contingent movement patterns, but did not discriminate between different degrees of movement fluency. In contrast, regions of the SNN were engaged more strongly when observing dyads with disturbed movement fluency. In conclusion, while the AON is involved in the general processing of contingent social actions, irrespective of their kinematic properties, the SNN is preferentially recruited when atypical kinematic properties prompt inferences about the agents' intentions. Hum Brain Mapp 35:1362–1378, 2014. © 2013 Wiley Periodicals, Inc.