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The apparatus based on the sinusoidal modulation of gravitational signal has been built to test the gravimeter. The combination of attracted mass is moved up and down by the guide rails with a large load-carrying capacity. The maximum acceleration produced by the apparatus reaches $220.0~\pm ~0.3$ nm/s2. A feedback control is carried out to modulate the moving distance of the attracted mass with an uncertainty of 0.03 mm. As a result, the acceleration is modulated in a sinusoidal wave with a frequency of 0.83 mHz, which is away from the frequencies of tidal signals and environmental disturbances. The CG6 gravimeter is verified by this apparatus. After considering the effects of the temperature, the atmosphere, the gravitational tide, etc, the uncertainty of the verifying is evaluated to be 0.5 nm/s2. The maximum difference in acceleration between the measured result of the CG6 gravimeter and the theoretical value produced by the apparatus is $1.2~\pm ~10.9$ nm/s2. It means that they agree well with each other within the error range. The uncertainty is mainly introduced by the random fluctuation of the CG6 gravimeter itself. This work provides a sinusoidal modulation method for verifying the gravimeters, which can greatly reduce the environmental influences, such as the effects of the gravity tide and the time drifting. The modulation frequency of the acceleration produced by the apparatus can be adjusted according to the testing requirement, which is helpful to study the response characteristics of the gravimeter at different frequencies.

A deep learning-powered VS approach combined with two free docking programs are proposed and evaluated for screening an ultra-large compound library to obtain diverse potential active compounds rapidly and efficiently. We found that it is a practical and transferable strategy to significantly reduce computational cost. Molecular docking-based virtual screening (VS) aims to choose ligands with potential pharmacological activities from millions or even billions of molecules. This process could significantly cut down the number of compounds that need to be experimentally tested. However, during the docking calculation, many molecules have low affinity for a particular protein target, which waste a lot of computational resources. We implemented a fast and practical molecular screening approach called DL-DockVS (deep learning dock virtual screening) by using deep learning models (regression and classification models) to learn the outcomes of pipelined docking programs step-by-step. In this study, we showed that this approach could successfully weed out compounds with poor docking scores while keeping compounds with potentially high docking scores against 10 DUD-E protein targets. A self-built dataset of about 1.9 million molecules was used to further verify DL-DockVS, yielding good results in terms of recall rate, active compounds enrichment factor and runtime speed. We comprehensively evaluate the practicality and effectiveness of DL-DockVS against 10 protein targets. Due to the improvements of runtime and maintained success rate, it would be a useful and promising approach to screen ultra-large compound libraries in the age of big data. It is also very convenient for researchers to make a well-trained model of one specific target for predicting other chemical libraries and high docking-score molecules without docking computation again.

During asymmetric division of Drosophilalarval neuroblasts, the fate determinant Prospero (Pros) and its adaptor Miranda (Mira) are segregated to the basal cortex through atypical protein kinase C (aPKC) phosphorylation of Mira and displacement from the apical cortex, but Mira localization after aPKC phosphorylation is not well understood. We identify Kin17, a DNA replication and repair protein, as a regulator of Mira localization during asymmetric cell division. Loss of Kin17 leads to aberrant localization of Mira and Pros to the centrosome, cytoplasm, and nucleus. We provide evidence to show that the mislocalization of Mira and Pros is likely due to reduced expression of Falafel (Flfl), a component of protein phosphatase 4 (PP4), and defects in dephosphorylation of serine-96 of Mira. Our work reveals that Mira is likely dephosphorylated by PP4 at the centrosome to ensure proper basal localization of Mira after aPKC phosphorylation and that Kin17 regulates PP4 activity by regulating Flfl expression.

Biomolecular condensates (biocondensates) formed via liquid–liquid phase-separation of soluble proteins have been studied extensively. However, neither the phase-separation of endoplasmic reticulum (ER) transmembrane protein nor a biocondensate with organized membranous structures has been reported. Here, we have discovered a spherical ER membranous biocondensate with puzzle-like structures caused by condensation of the ER-resident stimulator of interferon genes (STING) in DNA virus-infected or 2′3′-cGAMP (cyclic GMP-AMP)-treated cells, which required STING transmembrane domains, an intrinsically disordered region (IDR) and a dimerization domain. Intracellular 2′3′-cGAMP concentrations determined STING translocation or condensation. STING biocondensates constrained STING and TBK1 (TANK binding protein 1) to prevent innate immunity from overactivation, presumably acting like a ‘STING-TBK1-cGAMP sponge’. Cells expressing STING-E336G/E337G showed notably enhanced innate immune responses due to impaired STING condensation after viral infection at later stages. Microtubule inhibitors impeded the STING condensate gel-like transition and augmented type I-interferon production in DNA virus-infected cells. This membranous biocondensate was therefore named the STING phase-separator.

In this work, microwave treatment was introduced to a hydrothermal treatment process to degrade PCDD/Fs (Polychlorinated dibenzo-p-dioxins and dibenzofurans) in municipal solid waste incineration (MSWI) fly ash. Three process additives (NaOH, Na2HPO4, H2O), temperatures (150 °C, 185 °C, 220 °C) and reaction times (1 h, 2 h, 3 h) were investigated to identify their effect on the disposal of fly ash samples through orthogonal experiments. High-resolution gas chromatography–mass spectrometry (HRGC/MS) was applied to determine the PCDD/F concentrations in MSWI fly ash. The experimental results revealed that 83.7% of total PCDD/Fs was degraded. Reaction temperature was the most important factor for the degradation of the total PCDD/Fs. Both direct destruction and chlorination reactions (the chlorination degree of PCDFs increased) took part in the degradation of PCDD/Fs in fly ash, which was a new discovery. Several PCDD/F indexes determined by the concentration of indicative congeners were found to quantitatively characterize the dioxin toxicity of the fly ash. Furthermore, heavy metals in the fly ash sample were solidified using microwave-assisted hydrothermal treatment, which provided an experimental basis for the simultaneous disposal of dioxins and heavy metals. Thus, the microwave-assisted hydrothermal process should be considered for the future disposal of MSWI fly ash.

Glutathione peroxidase 4 (GPX4) is essential for cell membrane repair, inflammation suppression, and ferroptosis inhibition. GPX4 upregulation provides unique drug discovery opportunities for inflammation and ferroptosis-related diseases. However, rational design of protein activators is challenging. Until now, no compound has been reported to activate the enzyme activity of GPX4. Here, we identified a potential allosteric site in GPX4 and successfully found eight GPX4 activators using a novel computational strategy and experimental studies. Compound 1from the virtual screen increased GPX4 activity, suppressed ferroptosis, reduced pro-inflammatory lipid mediator production, and inhibited NF-κB pathway activation. Further chemical synthesis and structure–activity relationship studies revealed seven more activators. The strongest compound, 1d4, increased GPX4 activity to 150% at 20 μM in the cell-free assay and 61 μM in cell extracts. Therefore, we demonstrated that GPX4 can be directly activated using chemical compounds to suppress ferroptosis and inflammation. Meanwhile, the discovery of GPX4 activators verified the possibility of rational design of allosteric activators.

In this work, microwave irradiation was introduced into a hydrothermal process to solidify heavy metals in MSWI fly ash. The reagent, Na2HPO4, showed a significant effect on the synthesis of zeolite-like materials, reducing the leaching concentration of heavy metals. The heavy metals morphologically transformed from acid-soluble form to a more stable form after treatment. Furthermore, the leaching concentration of all heavy metals reached the standard limit with 30 min curing.In this work, microwave was introduced into hydrothermal process to solidify the heavy metals in MSWI fly ash. The heavy metals morphologically transformed from acid-soluble form to more stable form, after treatment. What’s more, the leaching concentration of all heavy metals reached the standard limit with 30 min curing.

The characteristic immunoprofile for the diagnosis of synovial sarcoma, a neoplasm of unclear tissue origin, is expression of transducer-like enhancer of split 1 (TLE-1), CD99, partial expression of cytokeratin, and epithelial membrane antigen by immunohistochemistry (IHC). Diagnostic dilemma or misdiagnosis can occur due to overlap in IHC and morphology with carcinomas, and particularly poorly differentiated and metastatic tumors. The frequency of TLE-1 and CD99 expression in carcinomas by IHC has not been previously assessed. We evaluated TLE-1 and CD99 expression in various carcinomas and evaluated the expression of the SS18 (SYT) gene rearrangement (a characteristic biomarker for synovial sarcoma) in tumors with TLE-1 and/or CD99 expression. Immunostains of TLE-1 and CD99 were performed in 100 various carcinomas. Seven of the 98 cases (7%) of carcinomas showed TLE-1 expression, including 1 each of prostate adenocarcinoma (ADCA), esophageal ADCA, basal cell carcinoma, adrenocortical carcinoma, endometrial ADCA, ovarian serous carcinoma, and small cell carcinoma. Twenty-one of the 100 cases (21%) of carcinomas demonstrated CD99 expression, including 6 prostate ADCA, 3 esophageal ADCA, 5 squamous cell carcinomas, 2 hepatocellular carcinomas, 1 each for endometrial ADCA, renal cell carcinoma, urothelial cell carcinoma, neuroendocrine carcinoma, and mucoepidermoid carcinoma. An esophageal ADCA was positive for both TLE-1 and CD99. None of the carcinomas with positive TLE-1 (n=7) or CD99 (n=21) by IHC showed SS18 gene rearrangement by fluorescent in situ hybridization. TLE-1 and CD99 expression were identified in 7% and 21% of carcinomas, respectively. This is a potential pitfall in the IHC interpretation for diagnosis of synovial sarcoma. SS18 gene rearrangement by fluorescent in situ hybridization is helpful for the diagnostically challenging cases, either for confirmation or exclusion of synovial sarcoma.

Enhancing the proportional limit of Al matrix composites (AMCs) is critical to the reliability of precision electronic instruments. In this paper, SiC/Al composites containing stacking faults (SFs) were successfully fabricated using pressure infiltration method. The proportional limit (σp5and σp100) of SiC/Al composites with SFs reached 65 MPa and 124 MPa, respectively, which is 8%∼22% higher than theoretical prediction of the Brown-Lukensempirical formula. The nucleation of SFs may be related to the lattice distortion fluctuation in Al matrix. The origin and stress conditions of SF nucleation in SiC/Al composites were deduced from the perspective of effective stacking fault energy (SFE). This paper provides theoretical support for preparing SF-containing AMCs with higher proportional limit.

Corey-Chaykovsky epoxidation is one of the versatile methods for synthesis of structurally diverse oxiranes. The extension of simplified Corey-Chaykovsky epoxidation has been investigated. Ketones and aromatic aldehydes were epoxidized in satisfactory to excellent yields with trimethylsulfonium iodide as an ylide precursor and crushed potassium hydroxide as a base in tertiary butanol. The scope and limitation of the simplified procedure were examined. The results revealed that the procedure is applicable to the epoxidation of ketones and aromatic aldehydes.

Mirk/dyrk1B is an arginine-directed protein kinase, which functions as a transcriptional activator and mediates serum-free growth of colon carcinoma cells by an unknown mechanism. We now report that turnover of the cdk inhibitor p27^kip1 and the G1-phase cyclin cyclin D1 is enhanced in each of 4 Mirk stable transfectants compared to vector control transfectants and Mirk kinase-inactive mutant transfectants. This enhanced turnover is proteasome-dependent and leads to lower protein levels of both p27^kip1 and cyclin D1. Lower protein levels of the cdk inhibitor p21^cip1 were also observed in the 4 Mirk stable transfectants. Mirk did not alter the activity of a p27^kip1 promoter construct or p27^kip1 mRNA levels by stable expression, indicating that the decrease in p27^kip1 protein levels was due to a posttranscriptional mechanism. These data are consistent with mirk enhancing the expression of some component common to the proteolysis of both p27^kip1 and cyclin D1. © 2002 Wiley-Liss, Inc.

Transforming growth factor β1 (TGFβ1) can act as a tumor suppressor or a tumor promoter depending on the characteristics of the malignant cell. We recently demonstrated that colon carcinoma cells transfected with oncogenic cellularK-rasV12, but not oncogenic cellular H-rasV12, switched from TGFβ1-insensitive to TGFβ1-growth-stimulated and also became more invasive (Yan, Z., Deng, X., and Friedman, E. (2001)J. Biol. Chem.276, 1555–1563). We now demonstrate that TGFβ1 growth stimulation of colon carcinoma cells is Ras-dependent and smad-independent. In U9 colon carcinoma cells, which are responsive to TGFβ1 by growth stimulation, a truncating mutation at Gln-311 was found in thesmad4gene. Very little smad4 protein was detected in these cells. Loss of smad4 protein was confirmed by functional studies. In U9 cells co-transfected wild-type smad4, but not mutant smad4, mediated response of the 3TP-lux and pSBE promoter reporter constructs to TGFβ1. Proliferation initiated by TGFβ1 in U9 cells required Ras-mediated down-regulation of p21cip1 protein. Less p21cip1 was associated with cdk2·cyclin complexes in TGFβ1-treated U9 cells, and the cdk2 complexes had increased kinase activity. Elevation of p21cip1 levels diminished proliferative response to TGFβ1. U9 cells expressing DN-N17ras neither proliferated in response to TGFβ1 nor down-regulated the cdk inhibitor p21cip1, and TGFβ1 activation of 3TP-lux in U9 cells was inhibited by DN-N17ras in a dose-dependent manner. TGFβ1 also decreased p21cip1 levels and stimulated proliferation in SW480 cells, which express mutant K-Ras but no smad4 protein. TGFβ1 did not activate or inhibit the p21cip1 promoter construct in U9 cells even in the presence of co-transfected smad4, or alter p21cip1 mRNA levels. Thus the decrease in p21cip1 levels was mediated by a TGFβ-initiated Ras-dependent, but smad-independent post-transcriptional mechanism.

Transforming growth factor-β1 (TGF-β1) can act as a tumor suppressor or a tumor promoter depending on the characteristics of the malignant cell. Each of three Ki-rasG12Vtransfectants of HD6-4 colon cancer cells had been shown to be more aggressive in vivothan controls in earlier studies (Yan, Z., Chen, M., Perucho, M., and Friedman, E. (1997) J. Biol. Chem.272, 30928–30936). We now show that stable expression of oncogenic Ki-rasG12Vconverts the HD6-4 colon cancer cell line from insensitive to TGF-β1 to growth-promoted by TGF-β1. Each of three Ki-rasG12Vtransfectants responded to TGF-β1 by an increase in proliferation and by decreasing the abundance of the Cdk inhibitor p21 and the tumor suppressor PTEN, whereas each of three wild-type Ki-rastransfectants remained unresponsive to TGF-β1. The wild-type Ki-rastransfectants lack functional TGF-β receptors, whereas all three Ki-rasG12Vtransfectants expressed functional TGF-β receptors that bound 125I-TGF-β1. The previous studies showed that in cells with wild-type Ki-ras, TGF-β receptors were not mutated, and receptor proteins were transported to the cell surface, but post-translational modification of TGF-β receptor III (TβRIII) was incomplete. We now show that the betaglycan form of TβRIII is highly modified following translation when transiently expressed in Ki-rasG12Vcells, whereas no such post-translational modification of TβRIII occurs in control cells. Antisense oligonucleotides directed to Ki-Ras decreased both TβRIII post-translational modification in Ki-rasG12Vcells and TGF-β1 down-regulation of p21, demonstrating the direct effect of mutant Ras. Therefore, one mechanism by which mutant Ki-Ras confers a more aggressive tumor phenotype is by enhancing TβRIII post-translational modification.

Colon carcinomas commonly contain mutations in Ki-ras4B, but very rarely in Ha-ras, suggesting that different Ras isoforms may have distinct functions in colon epithelial cell biology. In an earlier study we had demonstrated that oncogenic Ki-ras4BVal-12, but not oncogenic Ha-rasVal-12, blocks the apicobasal polarization of colon epithelial cells by preventing normal glycosylation of the integrin β1 chain of the collagen receptor. As a result, only the Ki-rasmutated cells exhibited altered cell to substratum attachment, whereas mutation of either Ras isoform activated mitogen-activated protein kinases. We have now asked whether intercellular adhesion proteins implicated in establishing basolateral polarity in colon epithelial cells are modulated by oncogenic Ki-Ras4BVal-12proteins but not oncogenic Ha-RasVal-12proteins. The embryonic adhesion protein carcinoembryonic antigen (CEA) was up-regulated on the mRNA and protein levels in each of three stable Ki-rasVal-12transfectant lines but in none of three stable Ha-rasVal-12transfectant lines. The elevated protein levels of CEA in Ki-ras4BVal-12transfectant cells were decreased by blocking expression of Ki-ras4BVal-12with antisense oligonucleotides. N-cadherin levels were decreased in only the Ki-rastransfectants, whereas E-cadherin levels were unchanged. Immunohistochemical analysis demonstrated that Ki-ras4BVal-12transfectant cells did not polarize into cells with discrete apical and basal regions and so could not restrict expression of CEA to the apical region. These unpolarized cells displayed elevated levels of CEA all along their surface membrane where CEA mediated random, multilayered associations of tumor cells. This aggregation was both calcium-independent and blocked by Fab′ fragments of anti-CEA monoclonal antibody col-1. Trafficking of the lysosomal cysteine protease cathepsin B may also be altered when cell polarity cannot be established. Ki-ras4BVal-12transfectant cells expressed 2-fold elevated protein levels of the lysosomal cysteine protease cathepsin B but did not up-regulate cathepsin B mRNA expression. One function of oncogenic c-Ki-Ras proteins in colon cancer progression may be to up-regulate CEA and thus to prevent the lateral adhesion of adjacent colon epithelial cells that normally form a monolayer in vivo.

Dendrite pruning of Drosophilasensory neurons during metamorphosis is induced by the steroid hormone ecdysone through a transcriptional program. In addition, ecdysone activates the eukaryotic initiation factor 4E-binding protein (4E-BP) to inhibit cap-dependent translation initiation. To uncover how efficient translation of ecdysone targets is achieved under these conditions, we assessed the requirements for translation initiation factors during dendrite pruning. We found that the canonical cap-binding complex eIF4F is dispensable for dendrite pruning, but the eIF3 complex and the helicase eIF4A are required, indicating that differential translation initiation mechanisms are operating during dendrite pruning. eIF4A and eIF3 are stringently required for translation of the ecdysone target Mical, and this depends on the 5′ UTR of Mical mRNA. Functional analyses indicate that eIF4A regulates eIF3-mRNA interactions in a helicase-dependent manner. We propose that an eIF3-eIF4A-dependent alternative initiation pathway bypasses 4E-BP to ensure adequate translation of ecdysone-induced genes.