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211.
Although superhydrophobic materials have attracted much research interest in anti-icing,some controversy still exists.In this research,we report a cost-effective method used to verify the contribution of area fraction to ice adhesion strength.We tried to partially-embed siliea nanopnarticles into microscale fabrics of a commercial polyamide mesh.Then,the area fraction could be determined by altering the mesh size.Generally,the ice adhesion strength decreases as the area fraction decreases.An ice adhesion strength of~1.9 kPa and a delayed freezing time of~1048 s can be obtained.We attribute the low ice adhesion strength to the combination of superhydro-phobicity and stress concentration.The superhydrophobicity prohibits the water from penetrating into the voids of the meshes,and the small actual contact area leads to stress concentration which promotes interfacial crack propagation.Moreover,our superhydrophobic mesh simultaneously exhibis a micro-nano hierarchical structure and a partally-cmbedded structure.Therefore,the as-prepared superhydrophobic mesh retained the ieephobicity after 20 icingldeicing cycles,and maintained its superhydrophobicity even afier 60 sandpaper-abrasion cycles and a 220"C thermal treatment. 相似文献
212.
Anne M. Bronikowski Richard P. Meisel Peggy R. Biga James
R. Walters Judith E. Mank Erica Larschan Gerald S. Wilkinson Nicole Valenzuela Ashley Mae Conard Joo Pedro de Magalhes Jingyue
Duan Amy E. Elias Tony Gamble Rita
M. Graze Kristin E. Gribble Jill A. Kreiling Nicole C. Riddle 《Aging cell》2022,21(2)
Sex differences in aging occur in many animal species, and they include sex differences in lifespan, in the onset and progression of age‐associated decline, and in physiological and molecular markers of aging. Sex differences in aging vary greatly across the animal kingdom. For example, there are species with longer‐lived females, species where males live longer, and species lacking sex differences in lifespan. The underlying causes of sex differences in aging remain mostly unknown. Currently, we do not understand the molecular drivers of sex differences in aging, or whether they are related to the accepted hallmarks or pillars of aging or linked to other well‐characterized processes. In particular, understanding the role of sex‐determination mechanisms and sex differences in aging is relatively understudied. Here, we take a comparative, interdisciplinary approach to explore various hypotheses about how sex differences in aging arise. We discuss genomic, morphological, and environmental differences between the sexes and how these relate to sex differences in aging. Finally, we present some suggestions for future research in this area and provide recommendations for promising experimental designs. 相似文献
213.
谷胱甘肽S-转移酶(GST)的同工酶mu(GSTM)高表达与卵巢癌顺铂耐药有关.以GST非选择性抑制剂依他尼酸设计二价潜抑制剂双依他尼酸乙醇胺(aminoethanol di-ethacrynic acid,ADEA),测定ADEA及其与还原型谷胱甘肽(glutathione,GSH)加合物对GST同工酶亚型A1、P1... 相似文献
214.
Zhongyi Fan Jingjing Duan Pu Luo Ling Shao Qiong Chen Xiaohua Tan Lei Zhang Xiaojie Xu 《Cell death & disease》2022,13(4)
Risk of metastasis is increased by the presence of chromosome 3 monosomy in uveal melanoma (UM). This study aimed to identify more accurate biomarker for risk of metastasis in UM. A total of 80 patients with UM from TCGA were assigned to two groups based on the metastatic status, and bioinformatic analyses were performed to search for critical genes for risk of metastasis. SLC25A38, located on chromosome 3, was the dominant downregulated gene in metastatic UM patients. Low expression of SLC25A38 was an independent predictive and prognostic factor in UM. The predictive potential of SLC25A38 expression was superior to that of pervious reported biomarkers in both TCGA cohort and cohort. Subsequently, its role in promoting metastasis was explored in vitro and in vivo. Knock-out of SLC25A38 could enhance the migration ability of UM cells, and promote distant metastasis in mice models. Through the inhibition of CBP/HIF-mediated pathway followed by the suppression of pro-angiogenic factors, SLC25A38 was situated upstream of metastasis-related pathways, especially angiogenesis. Low expression of SLC25A38 promotes angiogenesis and metastasis, and identifies increased metastatic risk and worse survival in UM patients. This finding may further improve the accuracy of prognostic prediction for UM.Subject terms: GSE22138Eye cancer, Prognostic markers 相似文献
215.
Tingting Duan Cifei Tang Zhuan Wu Zhaohui Cao Xiaobo Hu 《Acta biochimica et biophysica Sinica》2021,(1):128-130
Type 2 diabetes(T2D)is a chronic metabolic disease characterized by insulin resistance and hyperglycemia,which is ultimately linked to the loss of pancreaticβ-cells and their function[1].Understanding the pathological mechanisms ofβ-cell dysfunction in T2D may lead to development of new therapeutic approaches.Recently,compelling evidence suggests that members of the nuclear receptor 4A(NR4A)subgroup play a pivotal role inβ-cell loss[2].Nor1,also known as NR4A3,belongs to the NR4A subfamily,which also includes Nur77(NR4A1)and Nurr1(NR4A2),and is defined as a true orphan nuclear receptor with an unknown endogenous ligand or ligand independent[3].As a regulator of gene expression located in the nucleus,Nor1 exhibits tissue-specific expression,which selectively controls diverse biological processes,including cell proliferation,apoptosis,differentiation,immune homeostasis,and fuel utilization[4].Thus far,it was reported that Nor1 is involved in numerous pathologies such as cancer,inflammatory diseases,and Parkinson’s disease[4]. 相似文献
216.
217.
Yuexin Xu Xiaogang Bao Xiaoyun Chen Peixuan Wu Shiyu Chen Bowen Zhang Jing Ma Guohua Xu Duan Ma 《Journal of cellular and molecular medicine》2022,26(5):1643
Osteoporosis is one of the leading forms of systemic diseases related to bone metabolism in the world. STARD3 N‐terminal like (STARD3NL) showed robust association with osteoporosis‐related traits. Yet, the molecular functional mechanisms of STARD3NL in osteoblasts is still obscure. In this study, we demonstrated a high level of STARD3NL expression in the bone tissues from the patients with low bone mass and ovariectomized (OVX)‐induced osteoporotic mice. We identified Stard3nl as a potent factor that negatively and positively regulates osteoblast differentiation and cell proliferation, respectively. Furthermore, inhibition of Stard3nl induced β‐catenin gene expression and the nuclear translocation of β‐catenin, as well as Wnt signalling activities, contributing to the activation of Wnt/β‐catenin signalling. Mechanistic studies revealed that Stard3nl bound with Annexin A2 (Anxa2) to suppress β‐catenin expression, resulting into the suppression of Wnt signalling and downstream osteogenic differentiation. Moreover, adeno‐associated virus 9 (AAV9)‐mediated silencing of Stard3nl reversed bone loss in OVX‐induced osteoporotic mice by the injection into the knee joints. Collectively, our study revealed that Stard3nl suppressed osteogenesis via binding with Anxa2, resulting into the inactivation of Wnt signalling. It also highlights the preventive and therapeutic potential of STARD3NL as a specific and novel target for osteoporotic patients. 相似文献
218.
Ji-Cheng Huang Cui-Cui Duan Shan Jin Chuan-Bo Sheng Yu-Si Wang Zhan-Peng Yue Bin Guo 《International journal of biological sciences》2022,18(5):2047
Polycystic ovarian syndrome (PCOS) is one of the most prevalent endocrinopathies and the leading cause of anovulatory infertility, but its pathogenesis remains elusive. Although HB-EGF is involved in ovarian cancer progression, there is still no clarity about its relevance with PCOS. The present study exhibited that abundant HB-EGF was noted in follicular fluid from PCOS women, where it might induce the granulosa cells (GCs) production of more estrogen via the elevation of CYP19A1 expression after binding to EGFR. Furthermore, HB-EGF transduced intracellular downstream cAMP-PKA signaling to promote the phosphorylation of JNK and ERK whose blockage impeded the induction of HB-EGF on estrogen secretion. Meanwhile, HB-EGF enhanced the accumulation of intracellular Ca2+ whose chelation by BAPTA-AM abrogated the stimulation of HB-EGF on FOXO1 along with an obvious diminishment for estrogen production. cAMP-PKA-JNK/ERK-Ca2+ pathway played an important role in the crosstalk between HB-EGF and FOXO1. Treatment of GCs with HB-EGF resulted in mitochondrial dysfunction as evinced by the reduction of ATP content, mtDNA copy number and mitochondrial membrane potential. Additionally, HB-EGF facilitated the opening of mitochondrial permeability transition pore via targeting BAX and raised the release of cytochrome C from mitochondria into the cytosol to trigger the apoptosis of GCs, but this effectiveness was counteracted by estrogen receptor antagonist. Collectively, HB-EGF might induce mitochondrial dysfunction and GCs apoptosis through advancing estrogen hypersecretion dependent on cAMP-PKA-JNK/ERK-Ca2+-FOXO1 pathway and act as a promising therapeutic target for PCOS. 相似文献
219.
220.
In addition to the acid and neutral sphingomyelinases (SMase) that occur in most tissues, distinct alkaline sphingomyelinases occur in the mucosa of the gastrointestinal tract and human bile. These enzymes exhibit characteristic properties with regard to bile-salt dependence, protease resistance, and longitudinal distribution in the gut. Alkaline SMase has now been partially purified from human bile and from rat small intestine. It is thought to have a role in sphingomyelin (SM) digestion but may also be important for the generation of antiproliferative sphingolipid messengers in the gut. It occurs throughout the whole length of the intestine and also in the colon. It is decreased in colon cancer tissue compared to surrounding mucosa and is extremely low in colon mucosa from patients with familial adenomatous polyposis (FAP). This chapter reviews the properties and potential physiological and pathophysiological significance of alkaline SMase. It also briefly summarizes the knowledge about sphingolipid digestion and about the ceramidases of the gut. 相似文献