A quantitative map of nuclear pore assembly reveals two distinct mechanisms.

Understanding how the nuclear pore complex (NPC) is assembled is of fundamental importance to grasp the mechanisms behind its essential function and understand its role during the evolution of eukaryotes1-4. There are at least two NPC assembly pathways-one during the exit from mitosis and one during nuclear growth in interphase-but we currently lack a quantitative map of these events. Here we use fluorescence correlation spectroscopy calibrated live imaging of endogenously fluorescently tagged nucleoporins to map the changes in the composition and stoichiometry of seven major modules of the human NPC during its assembly in single dividing cells. This systematic quantitative map reveals that the two assembly pathways have distinct molecular mechanisms, in which the order of addition of two large structural components, the central ring complex and nuclear filaments are inverted. The dynamic stoichiometry data was integrated to create a spatiotemporal model of the NPC assembly pathway and predict the structures of postmitotic NPC assembly intermediates.

Regulating Phase Distribution of Dion-Jacobson Perovskite Colloidal Multiple Quantum Wells Toward Highly Stable Deep-Blue Emission.

Metal halide perovskite colloidal quantum wells (CQWs) hold great promise for modern photonics and optoelectronics. However, current studies focus on Ruddlesden-Popper (R-P) phase perovskite CQWs that contain bilayers of monovalent long-chain alkylamomoniums between the separated perovskite octahedra layers. The bilayers are packed back-to-back via weak van der Waals interaction, resulting in inferior charge carrier transport and easier decomposition of perovskite. This report first creates a new type of perovskite colloidal multiple QWs (CMQWs) in the form of Dion-Jacobson (D-J) structure by introducing an asymmetric diammonium cation. Furthermore, the phase distribution is optimized by the synergistic effect of valeric acid and zwitterionic lecithin, finally achieving pure deep-blue emission at 435 nm with narrow full width at half maximum. The diammonium layer in D-J perovskite CMQWs features extremely short width of only ≈0.6 nm, thereby contributing to more effective charge carrier transport and higher stability. Through the continuous photoluminescence (PL) measurement and corresponding theoretical calculation, the higher stability of D-J perovskite CMQWs than that of R-P structural CMQWs is confirmed. This work reveals the inherent superior stability of D-J structural CMQWs, which opens a new direction for fabricating stable perovskite optoelectronics.

Melatonin regulates cancer migration and stemness and enhances the anti-tumour effect of cisplatin.

Melatonin, a lipophilic hormone released from the pineal gland, has oncostatic effects on various types of cancers. However, its cancer treatment potential needs to be improved by deciphering its corresponding mechanisms of action and optimising therapeutic strategy. In the present study, melatonin inhibited gastric cancer cell migration and soft agar colony formation. Magnetic-activated cell sorting was applied to isolate CD133+ cancer stem cells. Gene expression analysis showed that melatonin lowered the upregulation of LC3-II expression in CD133+ cells compared to CD133- cells. Several long non-coding RNAs and many components in the canonical Wnt signalling pathway were altered in melatonin-treated cells. In addition, knockdown of long non-coding RNA H19 enhanced the expression of pro-apoptotic genes, Bax and Bak, induced by melatonin treatment. Combinatorial treatment with melatonin and cisplatin was investigated to improve the applicability of melatonin as an anticancer therapy. Combinatorial treatment increased the apoptosis rate and induced G0/G1 cell cycle arrest. Melatonin can regulate migration and stemness in gastric cancer cells by modifying many signalling pathways. Combinatorial treatment with melatonin and cisplatin has the potential to improve the therapeutic efficacy of both.

Safety, tolerability, pharmacokinetics and efficacy of HB0017, a humanized monoclonal antibody that targets interleukin-17A, in healthy participants and patients with moderate-to-severe plaque psoriasis.

BACKGROUND: Several interleukin (IL)-17 inhibitors have been approved for the treatment of moderate-to-severe plaque psoriasis (PsO). There is still scope for the development of affordable treatments for PsO. OBJECTIVES: To assess, in a phase Ia study, the safety, tolerability and pharmacokinetics (PK) of HB0017, a humanized monoclonal antibody that targets IL-17A, in healthy participants and patients with moderate-to-severe plaque PsO; and, in a phase Ib study, to assess the efficacy of HB0017 in patients with moderate-to-severe plaque PsO. METHODS: The phase Ia study (NCT04505033) was a randomized double-blind placebo-controlled dose-escalation study in healthy participants. Each cohort of 10 volunteers was randomly assigned to receive either a single dose of HB0017 (50 mg, 150 mg, 300 mg or 450 mg) or the matching placebo at a ratio of 4 : 1. The phase Ib study (NCT05442788) was a randomized double-blind placebo-controlled dose-escalation study in enrolled patients with moderate-to-severe plaque PsO. Each cohort of 10 patients was randomly assigned to receive either multiple doses of HB0017 (150 mg, 300 mg or 450 mg) or the matching placebo at a ratio of 4 : 1. RESULTS: HB0017 demonstrated dose-proportional linear PK and was tolerated across the dose range assessed. In the phase Ia and Ib studies, participants in both the HB0017 and placebo groups experienced treatment-emergent adverse events (69% vs. 87%, 96% vs. 100%, respectively). HB0017 demonstrated clinically meaningful effects in patients with moderate-to-severe plaque PsO. PASI 75 [≥ 75% improvement in Psoriasis Area and Severity Index (PASI)], PASI 90 (≥ 90% improvement in PASI) and static Physician Global Assessment (sPGA) 0/1 (i.e. 'clear' or 'almost clear') responses were 100% for the HB0017 300-mg group, with maximal improvements (100% or near 100% reductions from baseline) in PASI score observed at week 12, while the duration of effect was evident up to week 20. There was no clinical response in any participant in the placebo group in the phase Ib study. CONCLUSIONS: Overall, HB0017 showed acceptable safety and tolerability in both healthy participants and patients with moderate-to-severe plaque PsO. An encouraging signal of efficacy with a longer half-life provides HB0017 with the potential to be added to the currently available range of biologics targeting IL-17A.

Mapping the Identity of Transition Metal Doping and Surface Passivation in Indium Phosphide with Theoretical Calculation.

Understanding the electronic structure of doped InP quantum dots (QDs) is essential to optimize the material for specific optoelectronic applications. However, current synthesis approaches are often tedious and unfavorable for rational tunning. Herein, a combination of experimental and computational studies was conducted to address the doping mechanism and surface passivation of InP QDs. The successful dopant introduction requires low Cu doping concentration and heavy Mn doping, while the Ag doping amount is relatively moderate. This may correspond to the theoretical doping formation energy presented as Cu (-2.52 eV) < Ag (-1.76 eV) < Mn (-0.38 eV). As for surface passivation, inorganic ions and shell-like ZnS are unraveled through simulational investigation. Chloride ion promotes oriented growth toward tetrahedron morphology while nitrate-passivated InP QDs exhibit blurry transmission electron microscope (TEM) morphology. Correspondingly, the binding energy of chloride ion with (111) facet is -2.13 eV significantly lower than those of (110) and (100) facets. Further, the additional Zn 3d bands are more involved in the formation of conduction band, which optimized the Mn-doped InP with a 0.32 eV bandgap. These experimental and model results provide more microscopic details of doped InP, which can motivate theoretically exact control of guest ion stoichiometry with optimized characteristics for electrical devices.

Recent Advances in Blue Perovskite Quantum Dots for Light-Emitting Diodes.

Metal halide perovskite nanostructures have sparked intense research interest due to their excellent optical properties. In recent years, although the green and red perovskite light-emitting diodes (PeLEDs) have achieved a significant breakthrough with the external quantum efficiency exceeding 20%, the blue PeLEDs still suffer from inferior performance. Previous reviews about blue PeLEDs focus more on 2D/quasi-2D or 3D perovskite materials. To develop more stable and efficient blue PeLEDs, a systematic review of blue perovskite quantum dots (PQDs) is urgently demanded to clarify how PQDs evolve. In this review, the recent advances in blue PQDs involving mixed-halide, quantum-confined all-bromide, metal-doped and lead-free PQDs as well as their applications in PeLEDs are highlighted. Although several excellent PeLEDs based on these PQDs have been demonstrated, there are still many problems to be solved. A deep insight into the advantages and disadvantages of these four types of blue-emitting PQDs is provided. Then, their respective potential and issues for blue PeLEDs have been discussed. Finally, the challenges and outlook for efficient and stable blue PeLEDs based on PQDs are addressed.

Synergistic Effect of Halogen Ions and Shelling Temperature on Anion Exchange Induced Interfacial Restructuring for Highly Efficient Blue Emissive InP/ZnS Quantum Dots.

InP quantum dots (QDs) have attracted much attention owing to their nontoxic properties and shown great potential in optoelectronic applications. Due to the surface defects and lattice mismatch, the interfacial structure of InP/ZnS QDs plays a significant role in their performance. Herein, the formation of In-S and Sx -In-P1-x interlayers through anion exchange at the shell-growth stage is revealed. More importantly, it is proposed that the composition of interface is dependent on the synergistic effect of halogen ions and shelling temperature. High shelling temperature contributes to the optical performance improvement resulting from the formation of interlayers, besides the thicker ZnS shell. Moreover, the effect relates to the halogen ions where I- presents more obvious enhancement than Br- and Cl- , owing to their different ability to coordinate with In dangling bonds, which are inclined to form In-S and Sx -In-P1-x bonds. Further, the anion exchange under I- -rich environment causes a blue-shift of emission wavelength with shelling temperature increasing, unobserved in a Cl- - or Br- -rich environment. It contributes to the preparation of highly efficient blue emissive InP/ZnS QDs with emission wavelength of 473 nm, photoluminescence quantum yield of ≈50% and full width at half maximum of 47 nm.

Genome-Wide Identification and Characterization of the CC-NBS-LRR Gene Family in Cucumber (Cucumis sativus L.).

The NBS-LRR (NLR) gene family plays a pivotal role in regulating disease defense response in plants. Cucumber is one of the most important vegetable crops in the world, and various plant diseases, including powdery mildew (PM), cause severe losses in both cucumber productivity and quality annually. To characterize and understand the role of the CC-NBS-LRR(CNL) family of genes in disease defense response in cucumber plants, we performed bioinformatical analysis to characterize these genes systematically. We identified 33 members of the CNL gene family in cucumber plants, and they are distributed on each chromosome with chromosome 4 harboring the largest cluster of five different genes. The corresponding CNL family member varies in the number of amino acids and exons, molecular weight, theoretical isoelectric point (pI) and subcellular localization. Cis-acting element analysis of the CNL genes reveals the presence of multiple phytohormone, abiotic and biotic responsive elements in their promoters, suggesting that these genes might be responsive to plant hormones and stress. Phylogenetic and synteny analysis indicated that the CNL proteins are conserved evolutionarily in different plant species, and they can be divided into four subfamilies based on their conserved domains. MEME analysis and multiple sequence alignment showed that conserved motifs exist in the sequence of CNLs. Further DNA sequence analysis suggests that CsCNL genes might be subject to the regulation of different miRNAs upon PM infection. By mining available RNA-seq data followed by real-time quantitative PCR (qRT-PCR) analysis, we characterized expression patterns of the CNL genes, and found that those genes exhibit a temporospatial expression pattern, and their expression is also responsive to PM infection, ethylene, salicylic acid, and methyl jasmonate treatment in cucumber plants. Finally, the CNL genes targeted by miRNAs were predicted in cucumber plants. Our results in this study provided some basic information for further study of the functions of the CNL gene family in cucumber plants.

Characterization of lncRNAs and mRNAs Involved in Powdery Mildew Resistance in Cucumber.

Powdery mildew (PM) is a severe fungal disease of cucumber worldwide. Identification of genetic factors resistant to PM is of great importance for marker-assisted breeding to ensure cucumber production. Long noncoding RNAs (lncRNAs) and microRNAs (miRNAs) have been shown to play important roles in plant development and immunity; however, whether they have a role in PM response in cucurbit crops remains unknown. We performed strand-specific RNA sequencing and miRNA sequencing using RNA from cucumber leaves of two near-isogenic lines (NILs), S1003 and NIL (Pm5.1) infected with PM, and systematically characterized the profiles of cucumber lncRNAs and messenger RNA (mRNAs) responsive to PM. In total, we identified 12,903 lncRNAs and 25,598 mRNAs responsive to PM. Differential expression (DE) analysis showed that 119 lncRNAs and 136 mRNAs correlated with PM resistance. Functional analysis of these DE lncRNAs and DE mRNAs revealed that they are significantly associated with phenylpropanoid biosynthesis, phenylalanine metabolism, ubiquinone and other terpenoid-quinone biosynthesis, and endocytosis. Particularly, two lncRNAs, LNC_006805 and LNC_012667, might play important roles in PM resistance. In addition, we also predicted mature miRNAs and competing endogenous RNA (ceRNA) networks of lncRNA-miRNA-mRNA involved in PM resistance. A total of 49 DE lncRNAs could potentially act as target mimics for 106 miRNAs. Taken together, our results provide an abundant resource for further exploration of cucumber lncRNAs, mRNAs, miRNAs, and ceRNAs in PM resistance, and will facilitate the molecular breeding for PM-resistant varieties to control this severe disease in cucumber.

Optical and Morphological Properties of Single-Phased and Dual-Emissive InP/ZnS Quantum Dots via Transition Metallic and Inorganic Ions.

Single-phased and dual-emissive nanocrystals with broad emission are attractive fluorescent materials for optoelectronic devices due to their unique properties. Until now, the effect of different metallic cations and inorganic anions on III-V group quantum dots (QDs) concerning luminescence features and crystalline growth has been less explored. In this work, dual-emissive InP/ZnS QDs single-doped with transition-metal compounds (Cu2+, Ag+, or Mn2+) are synthesized to compare their optical and morphological properties. The corresponding doping concentrations to realize dual emission with comparative intensity for Cu, Ag, and Mn are 0.8, 6, and 80%, which vary greatly and might be attributed to different precursor reactivities. As for the morphological and internal structures, transmission electron microscopy (TEM) images indicate that transition-metal ions have no obvious effect on the morphological properties and a higher concentration of chloride anions binding with an In-rich interface could conduce to a homogeneous distribution and triangular growth through the comparison of different metal chlorides as precursors. X-ray photoelectron spectroscopy (XPS) results further demonstrate that the high-resolution In 3d spectrum of Mn-doped InP/ZnS QDs with MnCl2 is mainly dominated by In-P bonds, indicating fewer intermediate chemical states. These results concerning well-defined InP/ZnS QDs could promote more diverse insight into surface chemistry and help to better understand the growth mechanism, thus making it possible to regulate InP/ZnS QDs into desired formats for different practical applications like white light-emitting diodes (LEDs).

Dual-emission of silicon nanoparticles encapsulated lanthanide-based metal-organic frameworks for ratiometric fluorescence detection of bacterial spores.

Dipicolinic acid (DPA) is employed as a significant biomarker to detect Bacillus anthracis, which can do serious damages to the health of human beings. Hence, it is crucial to develop a fast and highly efficient strategy for DPA monitoring. In this work, based on silicon nanoparticles (Si NPs) and terbium metal-organic frameworks (Tb-MOFs), a hybrid structure (Si NPs/Tb-MOFs) as a novel dual-emitting fluorescence probe was fabricated for ratiometric detection of DPA, where blue light-emitting Si NPs (Ex: 280 nm; Em: 422 nm) are encapsulated into green light-emitting Tb-MOFs (Ex: 280 nm; Em: 547 nm). The optical properties and chemical composition of the as-obtained Si NPs/Tb-MOFs were characterized in detail. The Si NPs/Tb-MOFs probe not merely possesses the merits of a facile synthesis method but also is an excellent fluorescence probe. The response time towards DPA is less than 30 s, revealing that the process of detecting DPA can be completed in such a short time. The limit of detection for DPA is 5.3 nM, which is four orders of magnitude lower than an infectious dosage of anthrax spores for human beings (60 µM). This dual-emitting Si NPs/Tb-MOFs probe with interference-free and self-calibrating properties may be a potential candidate for further development in medical diagnosis. Graphical abstract.

A flipping-free 3D integral imaging display using a twice-imaging lens array.

Integral imaging is a promising 3D visualization technique for reconstructing 3D medical scenes to enhance medical analysis and diagnosis. However, the use of lens arrays inevitably introduces flipped images beyond the field of view, which cannot reproduce the correct parallax relation. To avoid the flipping effect in optical reconstruction, a twice-imaging lens array based integral display is presented. The proposed lens arrangement, which consists of a light-controlling lens array, a field lens array and an imaging lens array, allows the light rays from each elemental image only pass through its corresponding lens unit. The lens arrangement is optimized with geometrical optics method, and the proposed display system is experimentally demonstrated. A full-parallax 3D medical scene showing continuous viewpoint information without flipping is reconstructed in 45° field of view.

Wavefront aberration correction for integral imaging with the pre-filtering function array.

In integral imaging, the quality of a reconstructed image degrades with increasing viewing angle due to the wavefront aberrations introduced by the lens-array. A wavefront aberration correction method is proposed to enhance the image quality with a pre-filtering function array (PFA). To derive the PFA for an integral imaging display, the wavefront aberration characteristic of the lens-array is analyzed and the intensity distribution of the reconstructed image is calculated based on the wave optics theory. The minimum mean square error method is applied to manipulate the elemental image array (EIA) with a PFA. The validity of the proposed method is confirmed through simulations as well as optical experiments. A 45-degree viewing angle integral imaging display with enhanced image quality is achieved.

Mass-Transfer-Controlled Dynamic Interfacial Tension in Microfluidic Emulsification Processes.

Varied interfacial tension caused by the unsaturated adsorption of surfactants on dripping droplet surfaces is experimentally studied. The mass transfer and adsorption of surfactants, as well as the generation of fresh interfaces, are considered the main factors dominating the surfactant adsorption ratio on droplet surfaces. The diffusion and convective mass transfer of the surfactants are first distinguished by comparing the adsorption depth and the mass flux boundary layer thickness. A characterized mass transfer time is then calculated by introducing an effective diffusion coefficient. A time ratio is furthermore defined by dividing the droplet generation time by the characteristic mass transfer time, t/tm, in order to compare the rates of surfactant mass transfer and droplet generation. Different control mechanisms for different surfactants are analyzed based on the range of t/t(m), and a criterion time ratio using a simplified characteristic mass transfer time, t(m)*, is finally proposed for predicting the appearance of dynamic interfacial tension.

TRAF1 knockdown alleviates palmitate-induced insulin resistance in HepG2 cells through NF-κB pathway.

High-fat diet (HFD) and inflammation are key contributors to insulin resistance (IR) and Type 2 diabetes mellitus (T2DM). With HFD, plasma free fatty acids (FFAs) can activate the nuclear factor-κB (NF-κB) in target tissues, then initiate negative crosstalk between FFAs and insulin signaling. However, the molecular link between IR and inflammation remains to be identified. We here reported that tumor necrosis factor receptor-associated factor 1 (TRAF1), an adapter in signal transduction, was involved in the onset of IR in hepatocytes. TRAF1 was significantly up-regulated in insulin-resistant liver tissues and palmitate (PA)-treated HepG2 cells. In addition, we showed that depletion of TRAF1 led to inhibition of the activity of NF-κB. Given the fact that the activation of NF-κB played a facilitating role in IR, the phosphorylation of Akt and GSK3ß was also analyzed. We found that depletion of TRAF1 markedly reversed PA-induced attenuation of the phosphorylation of Akt and GSK3ß in the cells. The accumulation of lipid droplets in hepatocyte and expression of two key gluconeogenic enzymes, PEPCK and G6Pase, were also determined and found to display a similar tendency with the phosphorylation of Akt and GSK3ß. Glucose uptake assay indicated that knocking down TRAF1 blocked the effect of PA on the suppression of glucose uptake. These data implicated that TRAF1 knockdown might alleviate PA-induced IR in HepG2 cells through NF-κB pathway.

PCBP2 regulates hepatic insulin sensitivity via HIF-1α and STAT3 pathway in HepG2 cells.

Elevated free fatty acids (FFAs) are fundamental to the pathogenesis of hepatic insulin resistance. However, the molecular mechanisms of insulin resistance remain not completely understood. Transcriptional dysregulation, post-transcriptional modifications and protein degradation contribute to the pathogenesis of insulin resistance. Poly(C) binding proteins (PCBPs) are RNA-binding proteins that are involved in post-transcriptional control pathways. However, there are little studies about the roles of PCBPs in insulin resistance. PCBP2 is the member of the RNA-binding proteins and is thought to participate in regulating hypoxia inducible factor-1 (HIF-1α) and signal transducers and activators of transcription (STAT) pathway which are involved in regulating insulin signaling pathway. Here, we investigated the influence of PCBP2 on hepatic insulin resistance. We showed that the protein and mRNA levels of PCBP2 were down-regulated under insulin-resistant conditions. In addition, we showed that over-expression of PCBP2 ameliorates palmitate (PA)-induced insulin resistance, which was indicated by elevated phosphorylation of protein kinase B (AKT) and glycogen synthase kinase 3ß (GSK3ß). We also found that over-expression of PCBP2 inhibits HIF1α and STAT3 pathway. Furthermore, glucose uptake was found to display a similar tendency with the phosphorylation of Akt. The expressions of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase), two key gluconeogenic enzymes, were down-regulated following Over-expression of PCBP2. Accordingly, PA-induced intracellular lipid accumulation was suppressed in over-expression of PCBP2 HepG2 cells. In addition, we found that over-expression of PCBP2 inhibits HIF1α and STAT3 pathway. Our results demonstrate that PCBP2 was involved in hepatic insulin sensitivity might via HIF-1α and STAT3 pathway in HepG2 cells.

PRDX1 is involved in palmitate induced insulin resistance via regulating the activity of p38MAPK in HepG2 cells.

Studies have identified that type 2 diabetes mellitus (T2DM) patients displayed higher levels of plasma peroxiredoxin1(PRDX1) than non-diabetics. However, the impact of PRDX1 on insulin resistance and the underlying mechanism remains totally unknown. Here, we investigated the influence of PRDX1 on hepatic insulin resistance. We showed that the protein and mRNA levels of PRDX1 were significantly elevated under insulin-resistant conditions. In addition, we showed that interference of PRDX1 ameliorated palmitate-induced insulin resistance in HepG2 cells, which was indicated by elevated phosphorylation of protein kinase B (AKT) and of glycogen synthase kinase-3 (GSK3ß). Furthermore, the expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase), two key gluconeogenic enzymes, were down-regulated following PRDX1 depletion. Accordingly, glucose uptake was suppressed in PRDX1-interferred HepG2 cells. In addition, Over-expression of PRDX1 enhanced PA-induced insulin resistance in HepG2 cells. Moreover, we found that knocking down PRDX1 improves insulin sensitivity and decreased the activation of p38 mitogen-activated protein kinase (p38MAPK). Our results demonstrate that PRDX1 can induce hepatic insulin resistance by activating p38MAPK signaling and identifies potential targets for new treatments.