DNA-directed termination of RNA polymerase II transcription.

RNA polymerase II (RNAPII) transcription involves initiation from a promoter, transcriptional elongation through the gene, and termination in the terminator region. In bacteria, terminators often contain specific DNA elements provoking polymerase dissociation, but RNAPII transcription termination is thought to be driven entirely by protein co-factors. We used biochemical reconstitution, single-molecule studies, and genome-wide analysis in yeast to study RNAPII termination. Transcription into natural terminators by pure RNAPII results in spontaneous termination at specific sequences containing T-tracts. Single-molecule analysis indicates that termination involves pausing without backtracking. The "torpedo" Rat1-Rai1 exonuclease (XRN2 in humans) greatly stimulates spontaneous termination but is ineffectual on other paused RNAPIIs. By contrast, elongation factor Spt4-Spt5 (DSIF) suppresses termination. Genome-wide analysis further indicates that termination occurs by transcript cleavage at the poly(A) site exposing a new 5' RNA-end that allows Rat1-Rai1 loading, which then catches up with destabilized RNAPII at specific termination sites to end transcription.

Heat shock induces premature transcript termination and reconfigures the human transcriptome.

The heat shock (HS) response involves rapid induction of HS genes, whereas transcriptional repression is established more slowly at most other genes. Previous data suggested that such repression results from inhibition of RNA polymerase II (RNAPII) pause release, but here, we show that HS strongly affects other phases of the transcription cycle. Intriguingly, while elongation rates increase upon HS, processivity markedly decreases, so that RNAPII frequently fails to reach the end of genes. Indeed, HS results in widespread premature transcript termination at cryptic, intronic polyadenylation (IPA) sites near gene 5'-ends, likely via inhibition of U1 telescripting. This results in dramatic reconfiguration of the human transcriptome with production of new, previously unannotated, short mRNAs that accumulate in the nucleus. Together, these results shed new light on the basic transcription mechanisms induced by growth at elevated temperature and show that a genome-wide shift toward usage of IPA sites can occur under physiological conditions.

Translation stress and collided ribosomes are co-activators of cGAS.

The cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway senses cytosolic DNA and induces interferon-stimulated genes (ISGs) to activate the innate immune system. Here, we report the unexpected discovery that cGAS also senses dysfunctional protein production. Purified ribosomes interact directly with cGAS and stimulate its DNA-dependent activity in vitro. Disruption of the ribosome-associated protein quality control (RQC) pathway, which detects and resolves ribosome collision during translation, results in cGAS-dependent ISG expression and causes re-localization of cGAS from the nucleus to the cytosol. Indeed, cGAS preferentially binds collided ribosomes in vitro, and orthogonal perturbations that result in elevated levels of collided ribosomes and RQC activation cause sub-cellular re-localization of cGAS and ribosome binding in vivo as well. Thus, translation stress potently increases DNA-dependent cGAS activation. These findings have implications for the inflammatory response to viral infection and tumorigenesis, both of which substantially reprogram cellular protein synthesis.

Elongation Factor TFIIS Prevents Transcription Stress and R-Loop Accumulation to Maintain Genome Stability.

Although correlations between RNA polymerase II (RNAPII) transcription stress, R-loops, and genome instability have been established, the mechanisms underlying these connections remain poorly understood. Here, we used a mutant version of the transcription elongation factor TFIIS (TFIISmut), aiming to specifically induce increased levels of RNAPII pausing, arrest, and/or backtracking in human cells. Indeed, TFIISmut expression results in slower elongation rates, relative depletion of polymerases from the end of genes, and increased levels of stopped RNAPII; it affects mRNA splicing and termination as well. Remarkably, TFIISmut expression also dramatically increases R-loops, which may form at the anterior end of backtracked RNAPII and trigger genome instability, including DNA strand breaks. These results shed light on the relationship between transcription stress and R-loops and suggest that different classes of R-loops may exist, potentially with distinct consequences for genome stability.

Single-molecule characterization of Sen1 translocation properties provides insights into eukaryotic factor-dependent transcription termination.

Sen1 is an essential helicase for factor-dependent transcription termination in Saccharomyces cerevisiae, whose molecular-motor mechanism has not been well addressed. Here, we use single-molecule experimentation to better understand the molecular-motor determinants of its action on RNA polymerase II (Pol II) complex. We quantify Sen1 translocation activity on single-stranded DNA (ssDNA), finding elevated translocation rates, high levels of processivity and ATP affinities. Upon deleting the N- and C-terminal domains, or further deleting different parts of the prong subdomain, which is an essential element for transcription termination, Sen1 displays changes in its translocation properties, such as slightly reduced translocation processivities, enhanced translocation rates and statistically identical ATP affinities. Although these parameters fulfil the requirements for Sen1 translocating along the RNA transcript to catch up with a stalled Pol II complex, we observe significant reductions in the termination efficiencies as well as the factions of the formation of the previously described topological intermediate prior to termination, suggesting that the prong may preserve an interaction with Pol II complex during factor-dependent termination. Our results underscore a more detailed rho-like mechanism of Sen1 and a critical interaction between Sen1 and Pol II complex for factor-dependent transcription termination in eukaryotes.

Termination of non-coding transcription in yeast relies on both an RNA Pol II CTD interaction domain and a CTD-mimicking region in Sen1.

Pervasive transcription is a widespread phenomenon leading to the production of a plethora of non-coding RNAs (ncRNAs) without apparent function. Pervasive transcription poses a threat to proper gene expression that needs to be controlled. In yeast, the highly conserved helicase Sen1 restricts pervasive transcription by inducing termination of non-coding transcription. However, the mechanisms underlying the specific function of Sen1 at ncRNAs are poorly understood. Here, we identify a motif in an intrinsically disordered region of Sen1 that mimics the phosphorylated carboxy-terminal domain (CTD) of RNA polymerase II, and structurally characterize its recognition by the CTD-interacting domain of Nrd1, an RNA-binding protein that binds specific sequences in ncRNAs. In addition, we show that Sen1-dependent termination strictly requires CTD recognition by the N-terminal domain of Sen1. We provide evidence that the Sen1-CTD interaction does not promote initial Sen1 recruitment, but rather enhances Sen1 capacity to induce the release of paused RNAPII from the DNA. Our results shed light on the network of protein-protein interactions that control termination of non-coding transcription by Sen1.

Boosting Up Electrosynthesis of Urea with Nitrate and Carbon Dioxide via Synergistic Effect of Metallic Iron Cluster and Single-Atom.

Electrocatalytic conversion of nitrates and carbon dioxide to urea under ambient conditions shows promise as a potential substitute for traditional urea synthesis processes characterized by high consumption and pollution. In this study, a straightforward one-pot method is employed to prepare a highly efficient FeNC-Fe1N4 electrocatalyst, consisting of atomically dispersed Fe1N4 sites and metallic Fe clusters (FeNC) with particle size of 4-7 nm. The FeNC-Fe1N4 catalyst exhibits remarkable electrocatalytic activity for urea synthesis from nitrate anion (NO3 -) and carbon dioxide (CO2), achieving a urea production rate of 38.2 mmol gcat -1 h-1 at -0.9 V (vs RHE) and a Faradaic efficiency of 66.5% at -0.6 V (vs RHE). Both experimental and theoretical results conclusively demonstrate that metallic Fe clusters and Fe1N4 species provide active sites for the adsorption and activation of NO3 - and CO2, respectively, and the synergistic effect between Fe1N4 and metallic Fe clusters significantly enhances the electrochemical efficiency of urea synthesis. In all, this work contributes to the rational design and comprehensive synthesis of a dual-active site iron-based electrocatalyst, facilitating efficient and sustainable urea synthesis.

Two-sample Mendelian randomization analysis reveals causal relationships between blood lipids and venous thromboembolism.

Venous Thromboembolism (VTE) is a complex disease that can be classified into two subtypes: Deep Vein Thrombosis (DVT) and Pulmonary Embolism (PE). Previous observational studies have shown associations between lipids and VTE, but causality remains unclear. Hence, by utilizing 241 lipid-related traits as exposures and data from the FinnGen consortium on VTE, DVT, and PE as outcomes, we conducted two-sample Mendelian randomization (MR) analysis to investigate causal relationships between lipids and VTE, DVT and PE. The MR results identified that fatty acid (FA) unsaturation traits (Ratio of bis-allylic bonds to double bonds in lipids, and Ratio of bis-allylic bonds to total fatty acids in lipids) were associated with VTE (OR [95% CI]: 1.21 [1.15-1.27]; 1.21 [1.13-1.30]), DVT (OR [95%CI]: 1.24 [1.16-1.33]; 1.26 [1.16-1.36]) and PE (OR [95%CI]: 1.18 [1.08-1.29]; 1.18 [1.09-1.27]). Phosphatidylcholines exhibit potential causal effects on VTE and PE. Phosphatidylcholine acyl-alkyl C40:4 (PC ae C40:4) was negatively associated with VTE (OR [95% CI]: 0.79 [0.73-0.86]), while phosphatidylcholine diacyl C42:6 (PC aa C42:6) and phosphatidylcholine acyl-alkyl C36:4 (PC ae C36:4) were positively associated with PE (OR [95%CI]: 1.44 [1.20-1.72]; 1.22 [1.10-1.35]). Additionally, we found that medium LDL had a protective effect on VTE. Our study indicates that higher FA unsaturation may increase the risk of VTE, DVT, and PE. Different types of phosphatidylcholine have either promotive or inhibitory effects on VTE and PE, contributing to a better understanding of the risk factors for VTE.

Biomechanical evaluation of flash-frozen and cryo-sectioned papillary muscle samples by using sinusoidal analysis: cross-bridge kinetics and the effect of partial Ca2+ activation.

We examined the integrity of flash-frozen and cryo-sectioned cardiac muscle preparations (introduced by Feng and Jin, 2020) by assessing tension transients in response to sinusoidal length changes at varying frequencies (1-100 Hz) at 25 °C. Using 70-µm-thick sections, we isolated fiber preparations to study cross-bridge (CB) kinetics: preparations were activated by saturating Ca2+ as well as varying concentrations of ATP and phosphate (Pi). Our results showed that, compared to ordinary skinned fibers, in-series stiffness decreased to 1/2, which resulted in a decrease of isometric tension to 62%, but CB kinetics and Ca2+ sensitivity were little affected. The pCa study demonstrated that the rate constant of the force generation step (2πb) is proportionate to [Ca2+] at < 5 µM, suggesting that the activation mechanism can be described by a simple second order reaction. We also found that tension, stiffness, and magnitude parameters are related to [Ca2+] by the Hill equation, with a cooperativity coefficient of 4-5, which is consistent with the fact that Ca2+ activation mechanisms involve cooperative multimolecular interactions. Our results support the long-held hypothesis that Process C (Phase 2) represents the CB detachment step, and Process B (Phase 3) represents the force generation step. Moreover, we discovered that constant H may represent the work-performing step in cardiac preparations. Our experiments demonstrate excellent CB kinetics with two well-defined exponentials that can be more distinguished than those found using ordinary skinned fibers. Flash-frozen and cryo-sectioned preparations are especially suitable for multi-institutional collaborations nationally and internationally because of their ease of transportation.

Bismuth-Containing Quadruple Therapy for Helicobacter pylori Eradication: A Randomized Clinical Trial of 10 and 14 Days.

BACKGROUND: Bismuth-containing quadruple therapy is the first-line treatment for eradicating Helicobacter pylori (H. pylori). The optimal duration for H. pylori eradication using bismuth-containing quadruple therapy remains controversial. Therefore, we aimed to compare the clinical effects of the 10- and 14-day bismuth-containing quadruple treatment regimen to eradicate H. pylori. METHODS: Treatment-naïve patients with H. pylori infection (n = 1300) were enrolled in this multicenter randomized controlled study across five hospitals in China. They were randomized into 10- or 14-day treatment groups to receive bismuth-containing quadruple therapy as follows: vonoprazan 20 mg twice daily; bismuth 220 mg twice daily; amoxicillin 1000 mg twice daily; and either clarithromycin 500 mg twice daily or tetracycline 500 mg four times daily. At least 6 weeks after treatment, we performed a 13C-urea breath test to evaluate H. pylori eradication. RESULTS: The per-protocol eradication rates were 93.22% (564/605) and 93.74% (569/607) (p < 0.001) and the intention-to-treat eradication rates were 88.62% (576/650) and 89.38% (581/650) (p = 0.007) for the 10- and 14-day regimens, respectively. Incidence of adverse effects was lower in patients who received 10- vs. 14 days of treatment (22.59% vs. 28.50%, p = 0.016). We observed no significant differences in the compliance to treatment or the discontinuation of therapy because of severe adverse effects between the groups. CONCLUSION: Compared with the 14-day bismuth-containing quadruple regimens, the 10-day regimen demonstrated a non-inferior efficacy and lower incidence of adverse effects. Therefore, the 10-day regimen is safe and tolerated and could be recommended for H. pylori eradication (NCT05049902).

Preparation of (S)-epichlorohydrin using a novel halohydrin dehalogenase by selective conformation adjustment.

Chiral epichlorohydrin (ECH) is an attractive intermediate for chiral pharmaceuticals and chemicals preparation. The asymmetric synthesis of chiral ECH using 1,3-dicholoro-2-propanol (1,3-DCP) catalyzed by a haloalcohol dehalogenase (HHDH) was considered as a feasible approach. However, the reverse ring opening reaction caused low optical purity of chiral ECH, thus severely restricts the industrial application of HHDHs. In the present study, a novel selective conformation adjustment strategy was developed with an engineered HheCPS to regulate the kinetic parameters of the forward and reverse reactions, based on site saturation mutation and molecular simulation analysis. The HheCPS mutant E85P was constructed with a markable change in the conformation of (S)-ECH in the substrate pocket and a slight impact on the interaction between 1,3-DCP and the enzyme, which resulted in the kinetic deceleration of the reverse reactions. Compared with HheCPS, the catalytic efficiency (kcat(S)-ECH/Km(S)-ECH) of the reversed reaction dropped to 0.23-fold (from 0.13 to 0.03 mM-1 s-1), while the catalytic efficiency (kcat(1,3-DCP)/Km(1,3-DCP)) of the forward reaction only reduced from 0.83 to 0.71 mM-1 s-1. With 40 mM 1,3-DCP as substrate, HheCPS E85P catalyzed the synthesis of (S)-ECH with the yield up to 55.35% and the e.e. increased from 92.54 to >99%. Our work provided an effective approach for understanding the stereoselective catalytic mechanism as well as the green manufacturing of chiral epoxides.

Heterologous Expression and Characterization of a pH-Stable Chitinase from Micromonospora aurantiaca with a Potential Application in Chitin Degradation.

To promote the bioconversion of marine chitin waste into value-added products, we expressed a novel pH-stable Micromonospora aurantiaca-derived chitinase, MaChi1, in Escherichia coli and subsequently purified, characterized, and evaluated it for its chitin-converting capacity. Our results indicated that MaChi1 is of the glycoside hydrolase (GH) family 18 with a molecular weight of approximately 57 kDa, consisting of a GH18 catalytic domain and a cellulose-binding domain. We recorded its optimal activity at pH 5.0 and 55 °C. It exhibited excellent stability in a wide pH range of 3.0-10.0. Mg2+ (5 mM), and dithiothreitol (10 mM) significantly promoted MaChi1 activity. MaChi1 exhibited broad substrate specificity and hydrolyzed chitin, chitosan, cellulose, soluble starch, and N-acetyl chitooligosaccharides with polymerization degrees ranging from three to six. Moreover, MaChi1 exhibited an endo-type cleavage pattern, and it could efficiently convert colloidal chitin into N-acetyl-D-glucosamine (GlcNAc) and (GlcNAc)2 with yields of 227.2 and 505.9 mg/g chitin, respectively. Its high chitin-degrading capacity and exceptional pH tolerance makes it a promising tool with potential applications in chitin waste treatment and bioactive oligosaccharide production.

Revealing Temperature-Dependent Oxidation Dynamics of Ni Nanoparticles via Ambient Pressure Transmission Electron Microscopy.

Understanding the oxidation mechanism of metal nanoparticles under ambient pressure is extremely important to make the best use of them in a variety of applications. Through ambient pressure transmission electron microscopy, we in situ investigated the dynamic oxidation processes of Ni nanoparticles at different temperatures under atmospheric pressure, and a temperature-dependent oxidation behavior was revealed. At a relatively low temperature (e.g., 600 °C), the oxidation of Ni nanoparticles underwent a classic Kirkendall process, accompanied by the formation of oxide shells. In contrast, at a higher temperature (e.g., 800 °C), the oxidation began with a single crystal nucleus at the metal surface and then proceeded along the metal/oxide interface without voids formed during the whole process. Through our experiments and density functional theory calculations, a temperature-dependent oxidation mechanism based on Ni nanoparticles was proposed, which was derived from the discrepancy of gas adsorption and diffusion rates under different temperatures.

CuCeOx/CuO Catalyst Derived from the Layered Double Hydroxide Precursor: Catalytic Performance in NO Reduction with CO in the Presence of Water and Oxygen.

Valencies of metal species and lattice defects, such as oxygen vacancies, play a pivotal role in metal oxide-catalyzed reactions. Herein, we report a promising synthetic strategy for preparing CuO-supported CuCeOx catalysts (CuCeOx/CuO) by calcination of a hydrotalcite precursor [Cu6Ce2(OH)16]CO3·nH2O. The structural and chemical properties of catalysts were characterized by XRD, ICP-AES, TEM, TPR, NH3-TPD, XPS, Raman spectroscopy, and N2 adsorption, which revealed that the thermal pretreatment in an oxidative atmosphere caused segregation and reconstitution processes of the precursor, resulting in a mesoporous catalyst consisting of well-dispersed CuO-supported CuCeOx clusters of 1.8-3.2 nm in size with a high population of oxygen vacancies. The as-prepared catalyst shows excellent catalytic performance in the reduction of NO by CO in the absence as well as in the presence of water and oxygen. This behavior is attributed to its high oxygen defect concentration facilitating the interplay of the redox equilibria between Cu2+ and reduced copper species (Cu+/Cu0) and (Ce4+/Ce3+). The high surface population of oxygen vacancies and in situ-generated metallic copper species have been evidenced by Raman spectroscopy and X-ray photoelectron spectroscopy. The layered double hydroxide-derived CuCeOx/CuO also showed good water tolerance and long-term stability. In situ infrared spectroscopy investigations indicated that adsorbed hyponitrite species are the main reaction intermediates of the NO conversion as also corroborated by theoretical simulations.

Cold plasma enhanced natural edible materials for future food packaging: structure and property of polysaccharides and proteins-based films.

Natural edible films have recently gained a lot of interests in future food packaging. Polysaccharides and proteins in edible materials are not toxic and widely available, which have been confirmed as sustainable and green materials used for packaging films due to their good film-forming abilities. However, polysaccharides and proteins are hydrophilic in nature, they exhibit some undesirable material properties. Cold plasma (CP), as an innovative and highly efficient technology, has been introduced to improve the performance of polysaccharides and proteins-based films. This review mainly presents the basic information of polysaccharides and proteins-based films, principles of CP modified biopolymer films, and the effects of CP on the structural changes including surface morphology, surface composition, and bulk modification, and properties including wettability, mechanical properties, barrier properties, and thermal properties of polysaccharides, proteins, and polysaccharide/protein composite-based films. It is concluded that the CP modified performances are mainly depending on the polysaccharides and proteins raw materials, CP generation types and treatment conditions. The existing difficulties and future trends are also discussed. Despite natural materials currently not fully substitute for traditional plastic materials, CP has exhibited an effective solution to shape the future of natural materials for food packaging.

Efficacy and safety of a 14-day modified concomitant therapy for refractory Helicobacter pylori infection: a pilot study.

BACKGROUND AND AIM: After three treatment failures, Helicobacter pylori infection is deemed refractory as antibiotic treatment options become significantly limited. This study evaluated the efficacy and safety of a 14-day modified concomitant therapy for managing refractory H. pylori infection. METHODS: Patients who had failed to respond to three or more rounds of H. pylori therapies were recruited for this study. They received a 14-day modified concomitant therapy, including esomeprazole 40 mg, amoxicillin 1000 mg, and furazolidone 100 mg twice daily and tetracycline 500 mg four times daily. Demographic data, adverse events, and patient compliance were recorded. The presence of H. pylori was reevaluated 6 weeks following treatment. Eradication rate was assessed as the primary outcome. RESULTS: Overall, 59 participants received the 14-day modified concomitant therapy. In the intention-to-treat and per-protocol analyses, the eradication rate was 84.7% (50/59) and 89.3% (50/56), respectively. H. pylori was successfully isolated from 75.0% (12/16) of patients. The resistance rate of H. pylori to metronidazole, levofloxacin, and clarithromycin was 91.7% (11/12), 58.3% (7/12), and 50.0% (6/12), respectively. Resistance to amoxicillin, furazolidone, or tetracycline was not observed. The frequency of adverse events was 35.6% (21/59), with no serious adverse events reported. CONCLUSION: The 14-day modified concomitant therapy appears to be appropriate for refractory H. pylori infection and is particularly promising for the Chinese population. A randomized controlled trial is warranted to verify its efficacy, especially in the current environment of increasing antibiotic resistance.

Efficacy and Safety of Vonoprazan and Amoxicillin Dual Therapy for Helicobacter pylori Eradication: A Systematic Review and Meta-Analysis.

INTRODUCTION: Vonoprazan, a novel potassium-competitive acid blocker, has a strong acid suppression effect and potent efficacy in acid-associated diseases, including Helicobacter pylori eradication. We performed a systematic review and meta-analysis to investigate the efficacy and safety of vonoprazan/amoxicillin dual therapy for H. pylori eradication. METHODS: We conducted a systematic literature search through PubMed, Web of Science, EMBASE, and the Cochrane Library up to June 2022, to identify randomized controlled trials and cohort studies comparing vonoprazan/amoxicillin dual therapy and triple therapies for H. pylori eradication. Primary outcomes were cure rates and relative efficacy. Secondary outcomes included adverse events, dropout rate, and subgroup analysis. RESULTS: Five studies with 1,852 patients were included in the analysis. The cure rates of vonoprazan/amoxicillin dual therapy were 85.6% with 95% confidence interval (CI) of 79.7-91.5% and 88.5% (95% CI: 83.2-93.8%) in the intention-to-treat and per-protocol analyses. The efficacy of vonoprazan/amoxicillin dual therapy was not inferior to that of triple therapy with pooled risk ratio (RR) of 1.03 (95% CI: 0.97-1.10) and 1.02 (95% CI: 0.98-1.08) in intention-to-treat and per-protocol analyses; while it was significantly superior to the omeprazole or lansoprazole-based triple therapy (RR = 1.15, 95% CI: 1.05-1.25, p = 0.001). For clarithromycin-resistant strains, vonoprazan/amoxicillin dual therapy showed superiority to vonoprazan-based triple therapy (86.7% vs. 71.4%, RR = 1.20, 95% CI: 1.03-1.39, p = 0.02); however, vonoprazan/amoxicillin dual therapy was significant inferior to vonoprazan-based triple therapy for clarithromycin-sensitive strains (83.0% vs. 92.8%, RR = 0.90, 95% CI: 0.85-0.95, p = 0.0002). The adverse effects of vonoprazan/amoxicillin dual therapy were lower than those of triple therapy (21.2% vs. 26.5%, RR = 0.86, 95% CI: 0.73-1.01, p = 0.06), especially the incidence of diarrhea (p = 0.01). CONCLUSIONS: The efficacy of vonoprazan/amoxicillin dual therapy is noninferior to vonoprazan-based triple therapy but superior to the omeprazole or lansoprazole-based triple therapy and has less side effects. Patients with clarithromycin-resistant strains are particularly expected to benefit from vonoprazan/amoxicillin dual therapy.

Statistical analysis of the performance of a variety of first-principles schemes for accurate prediction of binary semiconductor band gaps.

Standard density functional theory (DFT) approximations tend to strongly underestimate band gaps, while the more accurate GW and hybrid functionals are much more computationally demanding and unsuitable for high-throughput screening. In this work, we have performed an extensive benchmark of several approximations with different computational complexity [G0W0@PBEsol, HSE06, PBEsol, modified Becke-Johnson potential (mBJ), DFT-1/2, and ACBN0] to evaluate and compare their performance in predicting the bandgap of semiconductors. The benchmark is based on 114 binary semiconductors of different compositions and crystal structures, for about half of which experimental band gaps are known. Surprisingly, we find that, compared with G0W0@PBEsol, which exhibits a noticeable underestimation of the band gaps by about 14%, the much computationally cheaper pseudohybrid ACBN0 functional shows a competitive performance in reproducing the experimental data. The mBJ functional also performs well relative to the experiment, even slightly better than G0W0@PBEsol in terms of mean absolute (percentage) error. The HSE06 and DFT-1/2 schemes perform overall worse than ACBN0 and mBJ schemes but much better than PBEsol. Comparing the calculated band gaps on the whole dataset (including the samples with no experimental bandgap), we find that HSE06 and mBJ have excellent agreement with respect to the reference G0W0@PBEsol band gaps. The linear and monotonic correlations between the selected theoretical schemes and experiment are analyzed in terms of the Pearson and Kendall rank coefficients. Our findings strongly suggest the ACBN0 and mBJ methods as very efficient replacements for the costly G0W0 scheme in high-throughput screening of the semiconductor band gaps.

Sestrin2 mediates FOXM1 expression to block the EMT process in non-small cell lung cancer through the AMPK/YAP pathway.

Non-small cell lung cancer (NSCLC) is characterized by high incidence and mortality, severely threatening human health. The infinite growth and metastasis of NSCLC cells result in a poor prognosis. Therefore, our study was to investigate the mechanism of Sestrin2 on the epithelial-mesenchymal transition (EMT) process of NSCLC cells. Human embryonic lung fibroblasts, NSCLC cell lines, and nude mice were experimental subjects in this study. qRT-PCR and western blot were performed to evaluate the mRNA and protein expression of genes. CCK-8 and EdU assay were conducted to detect cell proliferation. The scratch test and Transwell assay were applied to examine cell migration and invasion. The bioinformatics analysis and Co-IP assay were employed to predict and consolidate the interaction between YAP and TEAD. We found the expression of Sestrin2 was declined but the expression of YAP was elevated in NSCLC cells. Sestrin2 sufficiency or YAP silencing could effectively impair cell growth and metastasis. Mechanistically, YAP interacted with TEAD to enhance FOXM1 expression. Additionally, the elevation of FOXM1 abolished the inhibitory influences of Sestrin2 sufficiency on NSCLC cell growth, invasion, and EMT process. Eventually, Sestrin2 elevation attenuated tumor growth in mice via modulation of the AMPK/YAP/FOXM1 axis, which was reversed by FOXM1 overexpression. Our consequences suggested Sestrin2 could inhibit the activation of YAP via prompting AMPK phosphorylation and then suppress FOXM1 expression through the interplay between YAP and TEAD to impair the capacities of NSCLC cell proliferation, migration, invasion, and EMT. This study provided a novel mechanism of Sestrin2 in NSCLC.

Revealing Surface Restraint-Induced Hexagonal Pd Nanocrystals via In Situ Transmission Electron Microscopy.

Achieving metal nanocrystals with metastable phase draws much attention due to their anticipated fascinating properties, wheras it is still challenging because their polymorphism nature and phase transition mechanism remain elusive. Here, phase stability of face-centered cubic (fcc) Pd nanocrystals was studied via in situ spherical aberration (Cs)-corrected transmission electron microscopy (TEM). By constructing a well-defined Pd/C composite structure, Pd nanocrystals encapsulated by graphite, the dispersion process of fcc Pd was observed through a nucleation and growth process. Interestingly, Cs-corrected scanning TEM analysis demonstrated that the newly formed Pd nanocrystals could adopt a metastable hexagonal phase, which was considered challenging to obtain. Accordingly, formation mechanism of the hexagonal Pd nanocrystals was proposed, which involved the combined effect of two factors: (1) templating of graphite and (2) size effect. This work is expected to offer new insight into the polymorphism of Pd nanocrystals and pave the way for the future design of metastable metal nanomaterials.