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41.
Xuan Che Jianzhang Wang Jiayi He Qin Yu Wenting Sun Shuyi Chen Gen Zou Tiantian Li Xinyue Guo Xinmei Zhang 《Journal of cellular and molecular medicine》2020,24(2):1724-1737
Adenomyosis is also called internal endometriosis and affects about 20% of reproductive‐aged women. It seriously reduces life quality of patients because current drug therapies face with numerous challenges. Long‐term clinical application of mifepristone exhibits wonderful therapeutic effects with mild side‐effects in many disorders since 1982. Since adenomyosis is a refractory disease, we investigate whether mifepristone can be applied in the treatment of adenomyosis. In this study, we investigated the direct effects of mifepristone on human primary eutopic endometrial epithelial cells and stromal cells in adenomyosis. We found that mifepristone causes cell cycle arrest through inhibiting CDK1 and CDK2 expressions and induces cell apoptosis via the mitochondria‐dependent signalling pathway in endometrial epithelial cells and stromal cells of adenomyosis. Furthermore, mifepristone inhibits the migration of endometrial epithelial cells and stromal cells through decreasing CXCR4 expression and restricts the invasion of endometrial epithelial cells via suppression of epithelial‐mesenchymal transition in adenomyosis. We also found that mifepristone treatment decreases the uterine volume, CA125 concentration and increases the haemoglobin concentration in serum for adenomyosis patients. Therefore, we demonstrate that mifepristone could serve as a novel therapeutic drug in the treatment of adenomyosis, and therefore, the old dog can do a new trick. 相似文献
42.
Bo‐fang Zhang Hong Jiang Jing Chen Qi Hu Shuo Yang Xiao‐pei Liu Gen Liu 《Journal of cellular and molecular medicine》2020,24(1):1099-1115
Myocardial infarction (MI) remains the leading cause of morbidity and mortality worldwide, and novel therapeutic targets still need to be investigated to alleviate myocardial injury and the ensuing maladaptive cardiac remodelling. Accumulating studies have indicated that lncRNA H19 might exert a crucial regulatory effect on cardiovascular disease. In this study, we aimed to explore the biological function and molecular mechanism of H19 in MI. To investigate the biological functions of H19, miRNA‐22‐3p and KDM3A, gain‐ and loss‐of‐function experiments were performed. In addition, bioinformatics analysis, dual‐luciferase reporter assays, RNA immunoprecipitation (RIP) assays, RNA pull‐down assays, quantitative RT‐PCR and Western blot analyses as well as rescue experiments were conducted to reveal an underlying competitive endogenous RNA (ceRNA) mechanism. We found that H19 was significantly down‐regulated after MI. Functionally, enforced H19 expression dramatically reduced infarct size, improved cardiac performance and alleviated cardiac fibrosis by mitigating myocardial apoptosis and decreasing inflammation. However, H19 knockdown resulted in the opposite effects. Bioinformatics analysis and dual‐luciferase assays revealed that, mechanistically, miR‐22‐3p was a direct target of H19, which was also confirmed by RIP and RNA pull‐down assays in primary cardiomyocytes. In addition, bioinformatics analysis and dual‐luciferase reporter assays also demonstrated that miRNA‐22‐3p directly targeted the KDM3A gene. Moreover, subsequent rescue experiments further verified that H19 regulated the expression of KDM3A to ameliorate MI‐induced myocardial injury in a miR‐22‐3p‐dependent manner. The present study revealed the critical role of the lncRNAH19/miR‐22‐3p/KDM3A pathway in MI. These findings suggest that H19 may act as a potential biomarker and therapeutic target for MI. 相似文献
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Hui Fang Xiuyi Fu Yuebin Wang Jing Xu Haiying Feng Weiya Li Jieting Xu Orawan Jittham Xuan Zhang Lili Zhang Ning Yang Gen Xu Min Wang Xiaowei Li Jiansheng Li Jianbing Yan Xiaohong Yang 《The Plant journal : for cell and molecular biology》2020,101(2):278-292
The nutritional traits of maize kernels are important for human and animal nutrition, and these traits have undergone selection to meet the diverse nutritional needs of humans. However, our knowledge of the genetic basis of selecting for kernel nutritional traits is limited. Here, we identified both single and epistatic quantitative trait loci (QTLs) that contributed to the differences of oil and carotenoid traits between maize and teosinte. Over half of teosinte alleles of single QTLs increased the values of the detected oil and carotenoid traits. Based on the pleiotropism or linkage information of the identified single QTLs, we constructed a trait–locus network to help clarify the genetic basis of correlations among oil and carotenoid traits. Furthermore, the selection features and evolutionary trajectories of the genes or loci underlying variations in oil and carotenoid traits revealed that these nutritional traits produced diverse selection events during maize domestication and improvement. To illustrate more, a mutator distance–relative transposable element (TE) in intron 1 of DXS2, which encoded a rate‐limiting enzyme in the methylerythritol phosphate pathway, was identified to increase carotenoid biosynthesis by enhancing DXS2 expression. This TE occurs in the grass teosinte, and has been found to have undergone selection during maize domestication and improvement, and is almost fixed in yellow maize. Our findings not only provide important insights into evolutionary changes in nutritional traits, but also highlight the feasibility of reintroducing back into commercial agricultural germplasm those nutritionally important genes hidden in wild relatives. 相似文献
44.
Philip J. Bergmann Gen Morinaga Elyse S. Freitas Duncan J. Irschick Günter P. Wagner Cameron D. Siler 《Proceedings. Biological sciences / The Royal Society》2020,287(1938)
Evolutionary reversals, including re-evolution of lost structures, are commonly found in phylogenetic studies. However, we lack an understanding of how these reversals happen mechanistically. A snake-like body form has evolved many times in vertebrates, and occasionally a quadrupedal form has re-evolved, including in Brachymeles lizards. We use body form and locomotion data for species ranging from snake-like to quadrupedal to address how a quadrupedal form could re-evolve. We show that large, quadrupedal species are faster at burying and surface locomotion than snake-like species, indicating a lack of expected performance trade-off between these modes of locomotion. Species with limbs use them while burying, suggesting that limbs are useful for burying in wet, packed substrates. Palaeoclimatological data suggest that Brachymeles originally evolved a snake-like form under a drier climate probably with looser soil in which it was easier to dig. The quadrupedal clade evolved as the climate became humid, where limbs and large size facilitated fossorial locomotion in packed soils. 相似文献
45.
İlker Zeki Kurtoğlu Kübra Ak Songül Genç 《Zeitschrift fur angewandte Ichthyologie》2021,37(6):809-815
In this study, we investigated the effects of different stocking densities water quality and blood parameters during the transportation of the Siberian sturgeon (Acipenser baerii). Experiments were carried out in high-density polyethylene tank with three different stocking densities (50, 100 and 150 kg/m3) for 20 h. Ammonium nitrogen (NH4-N) and nitrite nitrogen (NO2-N) were measured in the water samples. The erythrocyte, leucocyte, haematocrit (HCT), haemoglobin (Hb), cortisol, and sodium ion (Na+) were measured in blood samples. Ammonium nitrogen and nitrite nitrogen concentrations in the water have increased in parallel with the stocking density depending on the time. In the highest stocking density, the maximum levels of NH4-N and NO2-N at the 16th h reached 2.64 mg/L and 4.74 mg/L, respectively. Erythrocyte, leucocyte, HCT, and Hb values did not differ significantly between the experimental groups (p > .05). The results showed that fish could be transported safely for 20 h in 15℃ water temperature at 50 kg/m3 stocking density; however, stocking density of 100 kg/m3 and over could threaten fish welfare and health as from 16th h. 相似文献
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Irazú Contreras Marina T. Shio Annabelle Cesaro Philippe A. Tessier Martin Olivier 《PLoS neglected tropical diseases》2013,7(9)
The myeloid-related proteins (MRPs) 8/14 are small proteins mainly produced by neutrophils, which have been reported to induce NO production in macrophages. On the other hand, Leishmania survives and multiplies within phagocytes by inactivating several of their microbicidal functions. Whereas MRPs are rapidly released during the innate immune response, their role in the regulation of Leishmaniasis is still unknown. In vitro experiments revealed that Leishmania infection alters MRP-induced signaling, leading to inhibition of macrophage functions (NO, TNF-α). In contrast, MRP-primed cells showed normal signaling activation and NO production in response to Leishmania infection. Using a murine air-pouch model, we observed that infection with L. major induced leukocyte recruitment and MRP secretion comparable to LPS-treated mice. Depletion of MRPs significantly reduced these inflammatory events and augmented both parasite load and footpad swelling during the first 8 weeks post-infection, as also observed in MRP KO mice. On the contrary, mouse treatment with recombinant MRPs (rMRPs) had the opposite effect. Collectively, our results suggest that rapid secretion of MRPs by neutrophils at the site of infection may protect uninfected macrophages and favor a more efficient innate inflammatory response against Leishmania infection. In summary, our study reveals the critical role played by MRPs in the regulation of Leishmania infection and how this pathogen can subvert its action. 相似文献