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Diquat is a bipyridyl herbicide that has been widely used as a model chemical for in vivo studies of oxidative stress due to its generation of superoxide anions, and cytotoxic effects. There is little information regarding the toxic effects of diquat on the female reproductive system, particularly ovarian function. Thus, we investigated the reproductive toxic effects of diquat on female mice. Chronic exposure to diquat reduced ovary weights, induced ovarian oxidative stress, resulted in granulosa cell apoptosis, and disrupted oocyte developmental competence, as shown by reactive oxygen species (ROS) accumulation, decreased polar body extrusion rates and increased apoptosis-related genes expression. Additionally, after diquat treatment, the numbers of fetal mice and litter sizes were significantly reduced compared to those of control mice. Thus, our results indicated that chronic exposure to diquat induced reproductive toxicity in female mice by promoting the ROS production of gruanousa cells and ooctyes, impairing follicle development, inducing apoptosis, and reducing oocyte quality. In conclusion, our findings indicate that diquat can be used as a potent and efficient chemical for in vivo studies of female reproductive toxicity induced by oxidative stress. Moreover, the findings from this study will further enlarge imitative research investigating the effect of ovarian damage induced by oxidative stress on reproductive performance and possible mechanisms of action in large domestic animals.  相似文献   
134.
Osteosarcoma (OS) is one of the most common metastatic bone cancers, which results in significant morbidity and mortality. The important role of long non‐coding RNAs (lncRNAs) in the biological processes of OS has been demonstrated through several studies. In the current study, we evaluated the role of the lncRNA, LINC01128, in OS. We analysed the expression of LINC01128 in three OS gene expression omnibus (GEO) data sets GSE21257, GSE36001 and GSE42352. The expression of LINC01128 in OS tissues and matched non‐tumour tissues obtained from 50 OS patients was detected using qRT‐PCR. The association between LINC01128 expression and overall survival of OS patients was evaluated using the Kaplan‐Meier method. The effects of LINC01128 knockdown and overexpression were evaluated through in vitro and in vivo assays. The LINC01128/miR‐299‐3p/ MMP2 axis was verified using dual‐luciferase reporter assay and qRT‐PCR assays. GEO data sets analysis revealed that the expression of LINC01128 was increased in OS. Elevated LINC01128 expression was accompanied by shorter overall survival in OS patients. Functional studies revealed that LINC01128 knockdown reduced the proliferation, migration and invasion of OS cells both in vitro and in vivo. Mechanistically, LINC01128 sponged miR‐299‐3p to increase MMP2 expression. Rescue assays determined the role of the LINC01128/miR‐299‐3p/MMP2 axis in the proliferation, migration and invasion of OS cells. Additionally, the Wnt/β‐catenin signalling pathway was activated by LINC01128 and MMP2 in OS cell lines. In summary, this study demonstrates that LINC01128 facilitates OS by functioning as a sponge of miR‐299‐3p, thus promoting MMP2 expression and activating the Wnt/β‐catenin signalling pathway.  相似文献   
135.
Regenerative medicine is a burgeoning field that is important to combat challenging diseases and functional impairments. Compared with traditional cell therapies with evident shortcomings (e.g., cell suspension injection or tissue engineering with scaffolds), scaffold-free cell sheet technology enables transplanted cells to be grafted and fully maintain their viability on target sites. Clinical and experimental studies have advanced the application of cell sheet technology to numerous tissues and organs (e.g., liver, cornea and bone). However, previous reviews have failed to discuss vital aspects of this rapidly developing technology, and many new challenges are gradually emerging. This review aims to provide a comprehensive introduction to cell sheet technology from cell selection to the ultimate applications of cell sheets, and challenges and future visions are also described.  相似文献   
136.
The origin of cultivated tree peonies, known as the ‘king of flowers'' in China for more than 1000 years, has attracted considerable interest, but remained unsolved. Here, we conducted phylogenetic analyses of explicitly sampled traditional cultivars of tree peonies and all wild species from the shrubby section Moutan of the genus Paeonia based on sequences of 14 fast-evolved chloroplast regions and 25 presumably single-copy nuclear markers identified from RNA-seq data. The phylogeny of the wild species inferred from the nuclear markers was fully resolved and largely congruent with morphology and classification. The incongruence between the nuclear and chloroplast trees suggested that there had been gene flow between the wild species. The comparison of nuclear and chloroplast phylogenies including cultivars showed that the cultivated tree peonies originated from homoploid hybridization among five wild species. Since the origin, thousands of cultivated varieties have spread worldwide, whereas four parental species are currently endangered or on the verge of extinction. The documentation of extensive homoploid hybridization involved in tree peony domestication provides new insights into the mechanisms underlying the origins of garden ornamentals and the way of preserving natural genetic resources through domestication.  相似文献   
137.
Wu  Haitao  Guan  Qiang  Lu  Kangle  Batzer  Darold P. 《Hydrobiologia》2019,832(1):153-174
Hydrobiologia - Lake Malaŵi cichlids have evolved rapidly, extensively, and in some cases iteratively to fill an array of ecological niches; however, neither species richness nor trophic...  相似文献   
138.
基于InVEST模型的疏勒河流域碳储量时空变化研究   总被引:9,自引:0,他引:9  
刘洋  张军  周冬梅  马静  党锐  马靖靖  朱小燕 《生态学报》2021,41(10):4052-4065
研究区域土地利用方式与生态系统服务碳储量的关系,对于区域生态系统保护及经济社会可持续发展具有重要意义。利用InVEST模型碳储量模块和CA-Markov模型,探究并预测疏勒河流域1990-2015及2015-2040年流域生态系统碳储量时空变化特征及其与土地利用方式之间的关系。结果表明:疏勒河流域1990、1995、2000、2005、2010、2015年碳储量分别为7.994×108、7.996×108、7.998×108、8.038×108、8.064×108、8.071×108t,呈逐年增加趋势,累计增加7.7×106t。土地利用类型变化是导致生态系统碳储量变化的主要因素,未利用地向耕地和草地转化有利于碳储量增加,而草地向耕地和未利用地的转化则导致碳储量减少。疏勒河流域碳储量存在显著的空间格局,碳储量较高区域呈现"北部点状-中部带状-南部点状片状"特征,这种分布格局与流域土地利用类型紧密联系。预测表明至2040年疏勒河流域碳储量为9.128×108t,较2015年增加13.1%,主要原因是草地、耕地和林地面积较大幅度增长,提高了流域内的碳储量。  相似文献   
139.
Plasmonic nanorods and their clusters are the fundamental units in plasmonic nanoantenna engineering. A theory that can predict the resonance of single nanorod already exists but is in lack for a heterodimer. Here, we propose a model combining the effective circuit theory for the response of spherical nanoparticles together with standard transmission line theory for hemispherically capped nanorod antennas. The resonances of multiple orders are predictable by defining the reflection phase at the terminals of such antennas, in both symmetric and asymmetric coupled nanorods. The theoretical results compare favorably with full-wave finite element numerical calculations. By the analytical formula, it is easy to control the length of the antennas for regulating the cooperative resonant properties and consequently the radiation characteristics of a nearby electric dipole. Consequently, we obtain both commensurate and incommensurate resonance features in such nanorod-based heterodimer antennas, showing respectively cumulative and selective responses from the individual nanorods.  相似文献   
140.
So far, over 50 spontaneous male sterile mutants of tomato have been described and most of them are categorized as genetic male sterility. To date, the mechanism of tomato genetic male sterility remained unclear. In this study, differential proteomic analysis is performed between genetic male sterile line (2‐517), which carries the male sterility (ms1035) gene, and its wild‐type (VF‐11) using isobaric tags for relative and absolute quantification‐based strategy. A total of 8272 proteins are quantified in the 2–517 and VF‐11 lines at the floral bud and florescence stages. These proteins are involved in different cellular and metabolic processes, which express obvious functional tendencies toward the hydroxylation of the ω‐carbon in fatty acids, the tricarboxylic acid cycle, the glycolytic, and pentose phosphate pathways. Based on the results, a protein network explaining the mechanisms of tomato genetic male sterility is proposed, finding the compromising fat acid metabolism may cause the male sterility. These results are confirmed by parallel reaction monitoring, quantitative Real‐time PCR (qRT‐PCR), and physiological assays. Taken together, these results provide new insights into the metabolic pathway of anther abortion induced by ms1035 and offer useful clues to identify the crucial proteins involved in genetic male sterility in tomato.  相似文献   
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