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We used the molecular dynamics method to simulate the behavior of potassium perfluorohexanesulfonate (KPFOS) in water/gas system. The results indicate that PFOS− can spontaneously migrate to the water/gas interface and form a layered structure with hydrophobic tail chains facing the gas phase and hydrophilic sulfonic acid groups immersed in the water phase, while some PFOS− molecules within the solution formed spherical micelles. Both the number density and charge density distributions confirm that PFOS− and K+ are mainly distributed at the water/gas interface, and a small amount of PFOS− and K+ are distributed in the bulk solution. Based on the results of radial distribution function, the probability of K+ appearing near oxygen atoms in PFOS− is very high due to electrostatic attraction. Based on the IGMH analysis, the oxygen atoms in PFOS− can form multiple hydrogen bonds with adjacent water molecules, while there is only weak van der Waals interaction between K+ and water molecules. [ABSTRACT FROM AUTHOR]

Background: NME1 has been exploited as a potential translational target for decades. Substantial efforts have been made to upregulate the expression of NME1 and restore its anti-metastasis function in metastatic cancer. Methods: Cycloheximide (CHX) chase assay was used to measure the steady-state protein stability of NME1 and HSP90α. The NME1-associating proteins were identified by immunoprecipitation combined with mass spectrometric analysis. Gene knockdown and overexpression were employed to examine the impact of HSP90AA1 on intracellular NME1 degradation. The motility and invasiveness of breast cancer cells were examined in vitro using wound healing and transwell invasion assays. The orthotopic spontaneous metastasis and intra-venous experimental metastasis assays were used to test the formation of metastasis in vivo, respectively. Results: HSP90α interacts with NME1 and increases NME1 lifetime by impeding its ubiquitin-proteasome-mediated degradation. HSP90α overexpression significantly inhibits the metastatic potential of breast cancer cells in vitro and in vivo. A novel cell-permeable peptide, OPT22 successfully mimics the HSP90α function and prolongs the life span of endogenous NME1, resulting in reduced metastasis of breast cancer. Conclusion: These results not only reveal a new mechanism of NME1 degradation but also pave the way for the development of new and effective approaches to metastatic cancer therapy. [ABSTRACT FROM AUTHOR]

Purpose: The aim of our study was to investigate microRNA (miRNA) expression profiles in CD44+ ovarian cancer stem cells (ovarian CSCs). Methods: In this study, we enriched CD44+ ovarian CSCs using magnetic activated cell sorting (MACS). A combination of real-time quantitative PCR (qRT-PCR), western blot and sphere formation assays was used to demonstrate stem cell-like properties. RNA sequencing was used to detect the miRNA expression profiles in CD44+ ovarian CSCs. Transient transfection, qRT-PCR, western blot and sphere formation assays were further used to test the function of miR-181a-2-3p. Results: We found that CD44+ ovarian CSCs showed enhanced sphere formation and expression of stemness-associated genes (NANOG, OCT4, SOX2) compared to ovarian cancer cells. The RNA sequencing results showed that the miRNA expression profiles of CD44+ ovarian CSCs were different from those of ovarian cancer cells. GO and KEGG pathway analyses indicated that these miRNAs regulate stem cell-like properties in CD44+ ovarian CSCs. In addition, miR-181a-2-3p negatively regulates the stem cell-like properties of CD44+ ovarian CSCs by targeting EGR1. Conclusion: Our data suggest that miRNAs play important roles in regulating the stem cell-like properties of CD44+ ovarian CSCs. [ABSTRACT FROM AUTHOR]

The growth of carbon dioxide (CO2) hydrate in CO2 aqueous solution (box A), and in CO2 aqueous solution with structure I (sI) CO2 hydrate cell as seed (box B) under the same conditions of 275 K and 10 MPa, were simulated respectively. The total simulation time is 5000 ns. The nucleation process is very slow, so it is difficult to observe CO2 hydrate growth in box A without CO2 hydrate seed, CO2 just accumulates to form bubbles, while H2O still remains liquid, the F4 order parameter remains about –0.1. By contrast, beautiful CO2 hydrate in box B grows rapidly, CO2 is trapped in the cages formed by H2O molecules, F4 rises from 0.12 to 0.7 due to the formation of sI hydrate. The density of CO2 hydrate in box B is as high as 1.25 g/cm3, higher than that of seawater, which is beneficial to its permanent sealing on the seabed. In box B, in accordance with the independent gradient model based on Hirshfeld partition (IGMH) analysis, a H2O molecule forms four hydrogen bonds with surrounding H2O molecules, CO2 only has van der Waals interaction with surrounding water cages. In the actual large-scale CO2 storage process, especially for the rapid storage of CO2 in the form of hydrate, it is strongly recommended to pre-add CO2 hydrate crystals into the solution to achieve the purpose of rapid growth of CO2 hydrate. [ABSTRACT FROM AUTHOR]

The aim of the present work is to prepare polymeric materials and to be used as drag reducer. In this paper, a new type of drag reducer was synthesized with polymeric materials. Technically, N, N-dimethyl-N-hexadecyl allylammonium bromide (DHAB) was synthesized with 3-bromopropene and N, N-dimethylcetyl tertiary amine, and then cationic hydrophobically associating polyacrylamide P(AM-DHAB), the desired drag reducer, was synthesized. The chemical structures of the products were confirmed by IR and NMR. The molecular weight of the drag reducer was found to be 2.66 × 106 g/mol as measured by laser light scattering method. In fresh water, when the concentration of drag reducer is 0.03%, the highest drag reduction rate is reached up to 73.05%. However, when the concentration of drag reducer is further increased, the viscosity is increased and drag reduction rate is decreased; indicating high viscosity has a significant negative effect on drag reduction rate. While in brine, with a viscosity obviously lower than that in fresh water, the drag reduction rate was slightly lower than 70% when the concentration of drag reducer was 0.03%; increasing the concentration of P(AM-DHAB) did not lead to a significant increase in viscosity, instead, it caused the drag reduction rate to be higher than 70%. Therefore, low viscosity facilitates drag reduction performance. Potassium persulfate makes the viscosity of slick water decrease sharply, which helps promote the polymer degradation and thus prevent polymer damage to the reservoir. Scanning electron microscope (SEM) showed that the drag reducer featured an obvious network structure in fresh water before gel breaking, and that there was almost no network structure but a small number of crystallites after gel breaks. In contrast, in brine, no matter before and after gel breaking, only salt crystals were cleanly seen under electron microscope due to high concentration of salt. [ABSTRACT FROM AUTHOR]

Prussian blue (PB) is a well-known electrochromic material due to its fast response and high cycle stability. We used the multi-step electrodeposition to prepare the PB films (S-PB) with different thickness. SEM image shows that as-grown film has small particles on its surface, which is beneficial for improving electrochromic properties of thicker PB film. The S-PB film with a thickness of 410 nm shows a high transmittance modulation of 82.04% at λ = 680 nm. S-PB and CeO2-TiO2-Li films were used as working electrode and counter electrode separately to prepare electrochromic devices (ECDs), both of which are inorganic anode materials. At 680 nm wavelength, the device based on double anode materials changes transmittance from 71.25 to 11.71% and the coloration efficiency is 73.5 cm2/C. Moreover, the optical modulation of ECD does not change significantly when performing 10,000 cycles. [ABSTRACT FROM AUTHOR]

Sn-Si composite anodes with linear variation composition could be synthesized by co-sputtering method directly. Ductile Sn was used as an additive material for improving the capacity and electrical conductivity of the brittle Si since the synergetic effect. The deposited films possessed a unique phase-separated structure and is beneficial to buffer the volume expansion introduced by an alloying/dealloying process, and the distributed Sn particles improved the transportation of Li+ and remedy the inherent poor conductivity of Si. As a result, the optimal Sn-Si composite film (Sn:Si = 35.9:64.1) possessed a stable discharge capacity of 1134.0 mAh/g after two cycles and a high-capacity retention of 82.8% after 50 cycles. Si played an important role as a buffer matrix, and the increased Si content could suppress the growth of Sn grains, reduce the structural damage and enhance film adhesion. The obtained Sn-Si component film was one strong candidate for next-generation thin film anode. [ABSTRACT FROM AUTHOR]

Purpose: The long noncoding RNA (lncRNA) ZEB1-AS1 is reported overexpressed in sensitive ovarian cancer cells A2780 compared with paclitaxel (PTX)—and cisplatin (DDP)- resistant. However, the function and mechanism of ZEB1-AS1 in EOC cells still unknown. Methods: We used quantitative real-time PCR (qPCR) to detect ZEB1-AS1 expression in A2780 and A2780/R cells. A combination of siRNA, plasmids, CCK8 and flow cytometry was used to detect the effect of ZEB1-AS1 on ovarian cancer cell A2780 PTX and DDP resistance. Transcriptome sequencing, qPCR, and western blot were used for further mechanistic studies. Results: ZEB1-AS1 depletion using siRNA in chemosensitive A2780 cells significantly increased PTX and DDP resistance. In contrast, ZEB1-AS1 overexpression in PTX- and DDP-resistant A2780/resistant (A2780/R) cells reversed the observed drug resistance. Thus, ZEB1-AS1 plays an important role in PTX and DDP resistance in EOC cells. However, quantitative real-time PCR (qPCR) and western blot results suggested that ZEB1-AS1 did not regulate chemoresistance through regulation of ZEB1 protein. We used sequencing to detect mRNA expression changes in A2780 cells after ZEB1-AS1 silencing. The results indicated that MMP19 was the likely downstream factor of ZEB1-AS1. We further examined whether ZEB1-AS1 played an important role in chemoresistance by silencing MMP19 in ZEB1-AS1-overexpressing cells. CCK8 assay results suggested that MMP19 knockdown promoted ZEB1-AS1-induced chemoresistance to PTX and DDP in A2780 cells. Conclusion: This study is the first to reveal that ZEB1-AS1 plays a pivotal role in cancer chemoresistance. [ABSTRACT FROM AUTHOR]

For advanced all-solid-state lithium batteries, the solid electrolyte is one of the most critical components that significantly affect battery performance. Herein, solid electrolytes 75Li2S·(25-x)P2S5·xP2O5 (mol%) are successfully prepared via wet chemistry method. Their XRD patterns show that only the crystalline phase β-Li3PS4 is detected for x = 0, 1, 2, 3, 5 mol% and the highest room-temperature ionic conductivity of 2.53 × 10−4 S cm−1 is obtained when x = 2. Next, effects of heat treatment on the structure and electrochemical performance of 75Li2S·23P2S5·2P2O5 are systematically studied. The thermal stability, morphology, structure, and crystal phase of the 75Li2S·23P2S5·2P2O5 electrolyte heated at different temperatures are characterized by thermogravimetric analysis and differential scanning calorimetry (TGA-DSC), SEM, N2 adsorption/desorption, Raman, and XRD. The 75Li2S·23P2S5·2P2O5 electrolyte heat-treated at 320 °C exhibits the highest ionic conductivity of 2.72 × 10−4 S cm−1, the lowest electronic conductivity of 4.8 × 10−9 S cm−1, and excellent electrochemical stability against the metallic lithium electrode. When the heat treatment temperature further increases from 320 to 500 °C, the electrolyte partially decomposes into Li4P2S6 and Li2S. Our results underscore the importance of heat treatment for the synthesis and performance optimization of solid electrolytes for the application of high-energy solid-state batteries. [ABSTRACT FROM AUTHOR]

Di(2-ethylhexyl)phthalate (DEHP) is an estrogenic chemical that is widely used in polyvinyl products. We aimed to determine the mechanisms behind the effects of DEHP on ERα-negative breast cancer cells MDA-MB-231 invasion and matrix metalloproteinases-2/-9 (MMP-2/-9) up-regulation in this study. Transwell assay indicated that DEHP exposure (>50 μg/ml) significantly enhanced the invasion ability of MDA-MB-231 cells. Quantitative real-time PCR (qPCR) and western blotting revealed that MMP-2/-9 is overexpressed in mRNA and protein levels after DEHP treatment. Gelatin zymography consistently demonstrated that DEHP exposure also enhances the activity of MMP-2/-9. Immunofluorescence assay showed that DEHP could accelerate NF-kappaB (NF-κB) subunits-p65 translocation into the nucleus, which is confirmed by western blotting assay, suggesting that the ratio of nuclear/cytosolic level of p65 was significantly increased. Furthermore, the invasion and MMP-2/-9 overexpression of MDA-MB-231 cells after DEHP-treated were reversed by the NF-κB chemical inhibitor JSH-23 via drug inhibition assay. This study suggested that DEHP could promote ERα-negative breast cancer cells MDA-MB-231 invasion through activating NF-κB and MMP-2/-9 overexpression. [ABSTRACT FROM AUTHOR]

Heterogeneity is the major obstacle to breast cancer target therapy. Classification of breast cancer with significant biological process may reduce the influence of heterogeneity of intrinsic tumor. We used survival analysis to filter 95 gene sets and classify 638 breast cancer samples into two subtypes based on those gene sets associated with prognosis. Clinical outcome of two subtypes were evaluated with disease-free survival, distant metastasis-free survival, and overall survival levels in three databases and ER+, PR+ HER2+, and TNBC groups. We established a novel classification with 95 prognostic gene sets. In the training and validation cohorts, the subtype 1 was characterized by significant gene sets associated with regulation of metabolic process and enzyme activity and predicted obviously improved clinical outcome than subtype 2, which was enriched by tumor cell division, mitosis, and cell cycle-related gene sets ( P < 0.05). When evaluated prognostic impact of subtypes in ER+, PR+ HER2+, and TNBC groups, we found that patients in subtype 1 showed better prognosis in ER+ and PR+ groups ( P < 0.05) but had no difference from prognosis of subtype 2 in HER2+ and TNBC groups. These findings may have implications in understanding of breast cancer and filtering effective therapeutic strategies for targeted therapy. [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests that microRNAs (miRNAs) play an important role in regulating the pathways in adipose tissue that control processes such as adipogenesis, insulin resistance, and inflammation. MiR-143 is a well-characterized miRNA involved in adipogenesis and may be involved in regulating insulin resistance. Free fatty acids (FFAs) and adipokines, such as tumor necrosis factor-α (TNF-α), leptin, resistin, and interleukin-6 (IL-6), have already been identified as main regulators of obesity and insulin sensitivity. Therefore, we studied the effects of these inflammatory cytokines on the expression of miR-143. FFAs, resistin, and leptin downregulated miR-143 expression in human adipocytes, whereas TNF-α and IL-6 had little effect on miR-143 expression. These results suggest that the expression of miR-143 is affected by a variety of factors that are related to insulin sensitivity. Therefore, miR-143 may be an important mediator in the development of obesity-related insulin resistance. [ABSTRACT FROM AUTHOR]

Long noncoding RNA (lncRNA) has been recognized as a regulator of gene expression, and the dysregulation of lncRNAs is involved in the progression of many types of cancer, including epithelial ovarian cancer (EOC). To explore the potential roles of lncRNAs in EOC, we performed lncRNA and mRNA microarray profiling in malignant EOC, benign ovarian cyst and healthy control tissues. In this study, 663 transcripts of lncRNAs were found to be differentially expressed in malignant EOC compared with benign and normal control tissues. We also selected 18 altered lncRNAs to confirm the validity of the microarray analysis using quantitative real-time PCR (qPCR). Pathway and Gene Ontology (GO) analyses demonstrated that these altered transcripts were involved in multiple biological processes, especially the cell cycle. Furthermore, Series Test of Cluster (STC) and lncRNA-mRNA co-expression network analyses were conducted to predict lncRNA expression trends and the potential target genes of lncRNAs. We also determined that two antisense lncRNAs (RP11-597D13.9 and ADAMTS9-AS1) were associated with their nearby coding genes (FAM198B, ADAMTS9), which participated in cancer progression. This study offers helpful information to understand the initiation and development mechanisms of EOC. [ABSTRACT FROM AUTHOR]

As a solid energy source, CH 4 hydrate will inevitably break down physically as the result of geological movement or exploitation. Here, the molecular dynamics method was employed to simulate the uniaxial-deformation behavior of structure I (sI type) CH 4 hydrate under stress. The stress increases regardless of whether the hydrate is stretched or squeezed, and other physical parameters also changed, such as hydrate cage numbers, order parameters, and the number of water molecules. A noticeable difference is observed between the two systems. Upon stretching, the stress immediately recovers to 0 GPa once the hydrate is completely stretched apart. During the squeeze process, the stress is ultimately not zero since solid and liquid are always in contact. When the hydrate is stretched apart, about 5% of water molecules change from solid to liquid, about 7.8% of CH 4 molecules lose their shelter and become free due to the disintegration of water cages. While in the squeezing process, large cages (5 12 6 2 ) are crushed more easily than small cages (5 12 ); in the end, about 93.5% of large cages and 73% of small cages are crushed, and approximately 87.5% CH 4 is released from the cages. In mining CH 4 hydrates, caution must be exercised, as if the hydrates break as a result of stress, a large release of CH 4 may pose a security risk., (© 2024. The Author(s).)