Within‐species genetic diversity is shaped by multiple evolutionary forces within the confines of geography, and has cascading effects on the biodiversity of other taxa and levels. Invasive species ...are often initially limited in genetic diversity but still respond rapidly to their new range, possibly through ‘pre‐adapted' genotypes or multiple sources of genetic diversity, but little is known about how their genetic structure differs from that of native species and how it alters the genetic‐species diversity relationship. Here, we selected a widespread native species Phragmites australis and its co‐occurring invasive competitor Spartina alterniflora as our model plant species. We investigated the genetic structure of P. australis using two chloroplast fragments and ten nuclear microsatellites in 13 populations along the Chinese coastal wetlands. We discovered a distinct geographical differentiation, showing that the northern and southern populations harbored unique genotypes. We also found a significant increase in genetic diversity (allelic richness and expected heterozygosity) from south to north. Combined with previous studies of S. alterniflora, the Mantel tests revealed a significant correlation of genetic distances between P. australis and S. alterniflora even when controlling for geographic distance, suggesting that the invasive species S. alterniflora might exhibit a phylogeographic pattern similar to that of the native species to some extent. Furthermore, our results suggest that the S. alterniflora invasion has altered the relationship between the genetic diversity of the dominant native plant and the associated species richness of soil nematodes. The reason for the alteration of genetic‐species diversity relationship might be that the biological invasion weakens the environmental impact on both levels of biodiversity. Our findings contribute to understanding the latitudinal patterns of intraspecific genetic diversity in widespread species. This work on the genetic diversity analysis of native species also provides significant implications for the invasion stage and ecological consequences of biological invasions.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Adipose-derived mesenchymal stem cells (ADSCs) are considered to be seed cells in bone tissue engineering and emerging evidence indicates that circular RNAs (circRNAs) function in the osteogenic ...differentiation of ADSCs. The mechanisms of osteoblastic differentiation of ADSCs from the perspective of circRNA modulation are examined in this study. First, circRNA-23525 was upregulated during osteoblastic differentiation of ADSCs. Second, overexpression of circRNA-23525 increased Runx2, ALP and OCN at both mRNA and protein levels. Alkaline phosphatase (ALP) and Alizarin Red staining indicated a similar tendency. Silencing circRNA-23525 produced the opposite effect. Bioinformatics analysis with luciferase assays confirmed that circRNA-23525 functioned as a sponge for miR-30a-3p. In the osteoblastic differentiation of ADSCs, the dynamic expression of miR-30a-3p and circRNA-23525 resulted in an opposite trend at 3, 7 and 14 days. Overexpression of circRNA-23525 downregulated miR-30a-3p and knockdown of circRNA-23525 promoted the expression of miR-30a-3p. Bioinformatics methods and luciferase assays suggested that miR-30a-3p modulated Runx2 expression by targeting 3′UTR. Knockdown of miR-30a-3p facilitated osteogenesis in ADSCs and enhancing miR-30a-3p interfered with the osteogenic process. Finally, circRNA-23525 overexpression significantly increased Runx2 expression, while co-transfection of miR-30a-3p mimics reversed it. Runx2 expression was decreased in circRNA-23525-knockdown ADSCs but expression was rescued by including the miR-30a-3p inhibitor in the osteoblastic process. ALP activity and mineralized bone matrix confirmed the function of circRNA-23525/miR-30a-3p in osteogenesis. Taken together, the current study demonstrated that circRNA-23525 regulates Runx2 expression via targeting miR-30a-3p and is thus a positive regulator in the osteoblastic differentiation of ADSCs.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
MK-8776 is a recently described inhibitor that is highly selective for checkpoint kinase 1 (Chk1), which can weaken the DNA repair capacity in cancer cells to achieve chemo-sensitization. A number of ...studies show that MK-8776 enhances the cytotoxicity of hydroxyurea and gemcitabine without increasing normal tissue toxicities. Thus far, there is no evidence that MK-8776 can be used as a radiotherapy sensitization agent. In this study, we investigated the effects of MK-8776 on the radiosensitivity of 3 human triple-negative breast cancer (TNBC) cell lines MDA-MB-231, BT-549 and CAL-51. MK-8776 dose-dependently inhibited the proliferation of MDA-MB-231, BT-549 and CAL-51 cells with IC
values of 9.4, 17.6 and 2.1 μmol/L, respectively. Compared with irradiation-alone treatment, pretreatment with a low dose of MK-8776 (100-400 nmol/L) significantly increased irradiation-induced γH2A.X foci in the 3 TNBC cell lines, suggesting enhanced DNA damage by MK-8776, inhibited the cell proliferation and increased the radiosensitivity of the 3 TNBC cell lines. Similar results were obtained in MDA-MB-231 xenograft tumors in nude mice that received MK-8776 (15 or 40 mg/kg, ip) 26 d after irradiation. To explore the mechanisms underlying the radio-sensitization by MK-8776, we used TEM and found that irradiation significantly increased the numbers of autophagosomes in the 3 TNBC cell lines. Moreover, irradiation markedly elevated the levels of Atg5, and promoted the transformation of LC3-I to LC3-II in the cells. Pretreatment with the low dose of MK-8776 suppressed these effects. The above results suggest that MK-8776 increases human TNBC radiosensitivity by inhibiting irradiation-induced autophagy and that MK-8776 may be a potential agent in the radiosensitization of human TNBC.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Plant invasions profoundly impact both natural and managed ecosystems, and removal of the invasive plants addresses only part of the problem of restoring impacted areas. The rehabilitation of diverse ...communities and their ecosystem functions following removal of invasive plants is an important goal of ecological restoration. Arthropod assemblages and trophic interactions are important indicators of the success of restoration, but they have largely been overlooked in saltmarshes. We determined how arthropod assemblages and trophic interactions changed with the invasion of the exotic plant Spartina alterniflora and with the restoration of the native plant Phragmites australis following Spartina removal in a Chinese saltmarsh. We investigated multiple biotic and abiotic variables to gain insight into the factors underlying the changes in arthropod assemblages and trophic structure. We found that although Spartina invasion had changed arthropod diversity, community structure, feeding‐guild composition, and the diets of arthropod natural enemies in the saltmarsh, these changes could be reversed by the restoration of native Phragmites vegetation following removal of the invader. The variation in arthropod assemblages and trophic structure were critically associated with four biotic and abiotic variables (aboveground biomass, plant density, leaf N, and soil salinity). Our findings demonstrate the positive effects of controlling invasive plants on biodiversity and nutrient cycling and provide a foundation for assessing the efficacy of ecological restoration projects in saltmarshes.
土著盐沼恢复能逆转植物入侵所改变的节肢动物群落组合和营养相互作用
植物入侵深刻影响自然和人工生态系统，清除入侵植物只能解决入侵受损区域的部分问题。入侵植物清除后，恢复不同类型生物群落及其生态系统功能是生态恢复的重要目标。节肢动物群落组合和营养相互作用是生态恢复成功的重要标志性指标，但在盐沼恢复中却常常被忽视。本文研究了中国长江口盐沼中外来植物互花米草入侵，以及清除互花米草并恢复土著植物芦苇后，节肢动物群落组合和营养相互作用如何变化。此外，本研究还测定了其他的多种生物、非生物变量，以深入了解影响节肢动物群落和营养结构变化的主导因素。结果发现，虽然互花米草入侵改变了盐沼节肢动物的多样性、群落结构、取食功能群组成和天敌食性，但这些变化可在入侵植物清除并恢复芦苇植被后而发生恢复性逆转。节肢动物群落组合和营养结构的变化主要与4个生物、非生物变量(地上生物量、植株密度、叶片氮含量和土壤盐度)密切相关。这些结果表明，治理入侵植物并恢复土著植被对盐沼生物多样性和营养循环具有积极作用。本研究可为盐沼生态修复工程的效益评估提供科学依据。
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
To improve the understanding of coupling effect between dynamic recrystallization (DRX) behaviors and flow behaviors of as-cast AlCu4SiMg, a finite element (FE) simulation equipped with the models of ...DRX evolution was implemented. A series of isothermal compression tests were performed primarily on a Gleeble−3500 thermo-mechanical simulator in a temperature range of 648−748 K and a strain rate range of 0.01−10 s−1. According to the measured true stress−strain data, the strain hardening rate curves (dσ/dε versus σ) were plotted to identify the critical strains for DRX initiation (εc). By further derivation of the related material constants, the DRX volume fraction equation and the strain for 50% DRX (ε0.5) equation were solved. Accordingly, the aforementioned DRX equations were implanted into the FE model to conduct a series of simulations for the isothermal compression tests. The results show that during the evolution of DRX volume fraction at a fixed strain rate, the strain required for the same amount of DRX volume fraction increases with decreasing temperature. In contrast, at a fixed temperature, it increases with increasing strain rate. Ultimately, the DRX kinetics model of AlCu4SiMg alloy and the consequence of the FE analysis were validated by microstructure observations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The sweetgum inscriber (SI) Acanthotomicus suncei Cognato is an emerging bark beetle pest that seriously damages American sweetgum trees (Liquidambar styraciflua) and Chinese sweetgum trees ...(L. formosana) in China. Since 2013, SI has killed more than 30,000 sweetgum trees in Shanghai and adjacent areas. In Shanghai, SI was observed to emerge from infested wood between April–September and exhibited two generations per year. Both the flying populations and those in colonized logs were female‐biased. After the parental adult initiates a gallery, the emergence of new adults required 73.4 ± 0.7 days at 30°C and 163.5 ± 0.9 days at 20°C. SI could not sustain population development at constant temperatures ≤15°C. The fungi Geosmithia spp. and Phaeoacremonium tuscanum were common associates of SI. The results suggest that SI has a long flight period, and its development is sensitive to low temperatures. Fungi associated with SI were not pathogenic to American sweetgum trees, but their presence may indirectly increase the probability of tree mortality. Our findings contribute to the prevention and control of this important emerging bark beetle pest.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In order to reveal circular RNAs (circRNAs) differential expression profiles and investigate the function and mechanism of circRNAs in the metastasis of salivary adenoid cystic carcinoma (SACC), ...microarray was used to detect differentially expressed circRNAs in SACC-83 and SACC-lung metastasis (LM) cell lines. Up-regulated circRNAs were analyzed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses to further predict their function. Expression of candidate circRNA and microRNA (miRNA) was determined using quantitative real-time polymerase chain reaction (qRT-PCR). Constructed circRNA–miRNA–mRNA co-expression network was based on TargetScan, miRanda databases. Wound healing and transwell assays were completed to examine the effects of hsa_circRNA_001982 and miR-181a-5p on cell migration and invasion. qRT-PCR confirmed hsa_circRNA_092556, hsa_circRNA_101379, and hsa_circRNA_001982 up-regulation in SACC-LM. miR-181a-5p was down-regulated in SACC-LM and correlated with up-regulated hsa_circRNA_001982. Wound healing and transwell assays indicated that silencing hsa_circRNA_001982 inhibited the migration and invasion of the SACC-LM cells. Furthermore, over-expression of hsa_circRNA_001982 promoted the migration and invasion of SACC-83 cells. Interestingly, up-regulation or down-regulation of miR-181a-5p led to the opposite result in wound healing and transwell assays. Overall, differential expression circRNA profiles in SACC-83 and SACC-LM cells may reveal potential targets and a novel mechanism of circRNAs in the metastasis of SACC. Moreover, the interaction of hsa_circRNA_001982/miR-181a-5p is closely related to the metastasis of SACC cells.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The determination of intrinsic deformation parameters inducing grain refinement mechanism of dynamic recrystallization (DRX) contributes to the relative forming process design. For Ni80A superalloy, ...the processing maps were constructed by the derivation of the stress-strain data coming from a series of isothermal compression tests at temperatures of 1273-1473 K and strain rates of 0.01-10 s−1. According to the processing maps and microstructural validation, the deformation parameter windows with DRX mechanism were separated in an innovative deformation mechanism map. In addition, the deformation activation energy representing deformation energy barrier was introduced to further optimize such windows. Finally, the enhanced processing maps were constructed and the parameter domains corresponding to DRX mechanism and lower deformation barrier were determined as follows: at ɛ=0.3, domains: 1296-1350 K, 0.056-0.32 s−1 and 1350-1375 K, 0.035-0.11 s−1; at ɛ=0.5, domains: 1290-1348 K, 0.2-0.5 s−1 and 1305–1370 K, 0.035-0.2 s−1; at ɛ=0.7, domains: 1290–1355 K, 0.042–0.26 s−1; at ɛ=0.9, domains: 1298-1348 K, 0.037-0.224 s−1.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Tumor cells have unique metabolic programming that is biologically distinct from that of corresponding normal cells. Resetting tumor metabolic programming is a promising strategy to ameliorate drug ...resistance and improve the tumor microenvironment. Here, we show that carboxyamidotriazole (CAI), an anticancer drug, can function as a metabolic modulator that decreases glucose and lipid metabolism and increases the dependency of colon cancer cells on glutamine metabolism. CAI suppressed glucose and lipid metabolism utilization, causing inhibition of mitochondrial respiratory chain complex I, thus producing reactive oxygen species (ROS). In parallel, activation of the aryl hydrocarbon receptor (AhR) increased glutamine uptake via the transporter SLC1A5, which could activate the ROS-scavenging enzyme glutathione peroxidase. As a result, combined use of inhibitors of GLS/GDH1, CAI could effectively restrict colorectal cancer (CRC) energy metabolism. These data illuminate a new antitumor mechanism of CAI, suggesting a new strategy for CRC metabolic reprogramming treatment.
The cytostatic agent CAI suppresses glucose and lipid metabolism utilization and further increases tumour cell dependency on glutamine metabolism, suggesting a synergistic anticancer strategy with glutamine metabolic pathway inhibitors. Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
The chirality in thallium isotopes is investigated using the adiabatic and configuration-fixed constrained triaxial relativistic mean field theory. Several minima with prominent triaxial ...deformation and proper configuration, where the chiral doublet bands may appear, are obtained in odd-odd nuclei
Tl and odd-mass nuclei
Tl. Furthermore, the possible existence of multiple chiral doublet bands (M
χ
D) is demonstrated in
Tl. As the chiral doublet bands in
Tl and M
χ
D in
195
Tl have been observed experimentally, further experimental exploration for the chirality in
Tl and M
χ
D in thallium isotopes is expected to verify the predictions.
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