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A highly efficient and environmentally benign 1,3-dipolar cycloaddition of C, N - cyclic azomethine imines with 5-alkenyl thiazolones and 2-arylidenindane-1,3-diones is developed for the construction of congested quaternary spiro-carbon centers. All these transformations can be smoothly performed in ethanol at room temperature, providing a catalyst-free and atom-economical access to diversely substituted novel isoquinoline-fused spirocycles in almost quantitative yields with high diastereoselectivities. The promising anti-tumor activity of these structurally novel spirocyclic compounds is reported as well.

Introduction: The chemoresistance mechanism of diffuse large B-cell lymphoma (DLBCL) is still poorly understood, and patient prognosis remains unsatisfactory. This study aimed to investigate drug resistance mechanisms in non-germinal center B-cell-like (non-GCB) DLBCL. Methods: Doxorubicin (DOX)-resistant OCI-Ly3 cells were generated through long-term incubation of cells in a medium with gradually increasing DOX concentrations. The expression levels of genes related to drug metabolism were determined using a functional gene grouping polymerase chain reaction (PCR) array. Drug-resistant proteins were identified using bioinformatics, and molecular association networks were subsequently generated. The association and mechanism of key genes were determined using a dual-luciferase reporter assay System and chromatin immunoprecipitation (ChIP). The expression of drug-resistant genes and target genes was then measured using Western blotting and immunohistochemistry. The correlation between gene expressions was analyzed using Spearman’s rank correlation coefficient. Results: Using the PCR array, MDR1 was identified as the key gene that regulates DOX resistance in OCI-Ly3/DOX-A100, a non-GCB DLBCL cell line. The dual-luciferase reporter assay system demonstrated that MDR1 transcription could be inhibited by PRDM1. ChIP results showed that PRDM1 had the ability to bind to the promoter region (−1,132 to −996) of MDR1. In OCI-Ly3/DOX cells, NF-κB activity and PRDM1 expression decreased with an increase in drug-resistant index, whereas MDR1 expression increased with enhanced drug resistance. Immunohistochemical analysis revealed that relative MDR1 expression was higher than that of PRDM1 in human DLBCL tissue samples. A negative correlation was observed between MDR1 and PRDM1. Conclusion: In non-GCB DLBCL cells, NF-κB downregulates PRDM1 and thereby promotes MDR1 transcription by terminating PRDM1-induced transcriptional inhibition of MDR1. Such a mechanism may explain the reason for disease recurrence in non-GCB DLBCL after R-CHOP or combined CHOP with bortezomib treatment. Our findings may provide a potential therapeutic strategy for reducing drug resistance in patients with DLBCL.

Ligand inducible proteins that enable precise and reversible control of nuclear translocation of passenger proteins have broad applications ranging from genetic studies in mammals to therapeutics that target diseases such as cancer and diabetes. One of the drawbacks of the current translocation systems is that the ligands used to control nuclear localization are either toxic or prone to crosstalk with endogenous protein cascades within live animals. We sought to take advantage of salicylic acid (SA), a small molecule that has been extensively used in humans. In plants, SA functions as a hormone that can mediate immunity and is sensed by the non-expressor of pathogenesis-related (NPR) proteins. Although it is well recognized that nuclear translocation of NPR1 is essential to promoting immunity in plants, the exact subdomain of Arabidopsis thaliana NPR1 (AtNPR1) essential for SA mediated nuclear translocation is controversial. Here, we utilized the fluorescent protein mCherry as the reporter to investigate the ability of SA to induce nuclear translocation of the full-length NPR1 protein or its C-terminal transactivation (TAD) domain using HEK293 cells as a heterologous system. HEK293 cells lack accessory plant proteins including NPR3/NPR4 and are thus ideally suited for studying the impact of SA-induced changes in NPR1. Our results obtained using a stable expression system show that the TAD of AtNPR1 is sufficient to enable the reversible SA mediated nuclear translocation of mCherry. Our studies advance a basic understanding of nuclear translocation mediated by the TAD of AtNPR1 and uncover a biotechnological tool for SA mediated nuclear localization. This article is protected by copyright. All rights reserved.

MicroRNAs (miRNAs) contribute to osteoarthritis (OA) development. Nevertheless, the function and mechanism of miR-30b-5p in OA are unclear. In the present article, we gauged the miR-30b-5p level in OA patients and analyzed its correlation with OA stages. Then, we conducted in-vivo and in-vitro gain-of-function assays to determine the function of miR-30b-5p, silent information regulator 2 homolog 1 (SIRT1) and Fox. Cell counting Kit-8 (CCK-8) assay, BrdU assay and flow cytometry were utilized to gauge cell viability and apoptosis of human chondrocyte (HC-A). The targeting association between miR-30b-5p and SIRT1 was validated through the dual-luciferase reporter assay and RNA immunoprecipitation (RIP) experiment. The results signified that miR-30b-5p was up-regulated in OA patients, OA rats and interleukin-1β (IL-1β)-induced chondrocytes. The higher miR-30b-5p expression brought about progressive stages of OA patients and enhanced levels of pro-inflammatory mediators in the synovial fluid. Functionally, overexpressing miR-30b-5p hampered cell viability, aggravated chondrocyte apoptosis and NLRP3 inflammasome activation induced by IL-1β, while down-regulating miR-30b-5p exerted the reverse effects. The in-vivo experiment exhibited that down-regulating miR-30b-5p improved joint pain and loss of articular cartilage in the rats with restrained inflammation and NLRP3 inflammasome activation. Mechanistically, miR-30b-5p targeted the 3’-non-translated region (3’UTR) of SIRT1, and miR-30b-5p was inducible with NF-κB phosphorylation enhancement. Overexpressing SIRT1 or inhibiting NF-κB relieved miR-30b-5p-induced apoptosis and NLRP3 inflammasome activation by promoting FoxO3a, while down-regulating SIRT1 or FoxO3a reversed miR-30b-5p-in-induced anti-inflammatory and apoptosis-suppressive effects. Collectively, NF-κB-induced miR-30b-5p modulates chondrocyte apoptosis and OA progression by regulating the SIRT1-FoxO3a-mediated NLRP3 inflammasome.

Methylmercury (MeHg) is a potential neurotoxin that is highly toxic to the human central nervous system. Although MeHg neurotoxicity has been widely studied, the mechanism of MeHg neurotoxicity has not yet been fully elucidated. Some research evidence suggests that oxidative stress and autophagy are important molecular mechanisms of MeHg-induced neurotoxicity. Researchers have widely accepted that oxidative stress regulates the autophagy pathway. The current study reviews the activation of Nuclear factor-erythroid-2-related factor (Nrf2)-related oxidative stress pathways and autophagy signaling pathways in the case of MeHg neurotoxicity. In addition, autophagy mainly plays a role in the neurotoxicity of MeHg through mTOR-dependent and mTOR-independent autophagy signaling pathways. Finally, the regulation of autophagy by reactive oxygen species (ROS) and Nrf2 in MeHg neurotoxicity was explored in this review, providing a new concept for the study of the neurotoxicity mechanism of MeHg.

β-galactoside α-2,3-sialyltransferase 2 (ST3GAL2) is a member of the sialyltransferase family that mediates terminal modification of glycoproteins and glycolipids. ST3GAL2 has been found to play a role in obesity, aging, and malignant diseases. In this study, we cloned porcine ST3GAL2 (pST3GAL2) from porcine alveolar macrophages (PAMs), and its role in porcine reproductive and respiratory syndrome virus (PRRSV) infection was investigated by transcriptome analysis. pST3GAL2 was found to be located in the Golgi apparatus, and it was expressed at high levels in PRRSV-infected PAMs. Overexpression of pST3GAL2 resulted in a slight increase in PRRSV proliferation, and the interaction between pST3GAL2 and GP2a of PRRSV was detected by coimmunoprecipitation and confocal microscopy. The expression of pro-inflammatory cytokines (IFN-β, IL-2, IL-6, IL-18, IL-1β and TNF-α) was significantly inhibited in pST3GAL2-overexpressing, PRRSV-infected cells and upregulated in PRRSV-infected pST3GAL2-knockout cells, while the pattern of expression of anti-inflammatory cytokines (IL-4 and IL-10) was diametrically opposite. Our results demonstrate that the regulation of pST3GAL2 plays an important role in PRRSV proliferation and functional alterations in virus-infected cells. These results contribute to our understanding of the role of β-galactoside α-2,3-sialyltransferase 2 in antiviral immunity.

Methylmercury (MeHg) is a long-lasting organic environmental pollutant that poses a great threat to human health. Ingestion of seafood containing MeHg is the most important way by which it comes into contact with human body, where the central nervous system (CNS) is the primary target of MeHg toxicity. During periods of pre-plus postnatal, in particular, the brain of offspring is vulnerable to specific developmental insults that result in abnormal neurobehavioral development, even without symptoms in mothers. While many studies on neurotoxic effects of MeHg on the developing brain have been conducted, the mechanisms of oxidative stress in MeHg-induced neurodevelopmental toxicity is less clear. Hitherto, no single process can explain the many effects observed in MeHg-induced neurodevelopmental toxicity. This review summarizes the possible mechanisms of oxidative stress in MeHg-induced neurodevelopmental toxicity, highlighting modulation of Nrf2/Keap1/Notch1, PI3K/AKT, and PKC/MAPK molecular pathways as well as some preventive drugs, and thus contributes to the discovery of endogenous and exogenous molecules that can counteract MeHg-induced neurodevelopmental toxicity.

Messenger RNA (mRNA) vaccine is a promising candidate in cancer immunotherapy as it can encode tumor-associated antigens with an excellent safety profile. Unfortunately, the inherent instability of RNA and translational efficiency are major limitations of RNA vaccine. Here, we report an injectable hydrogel formed with graphene oxide (GO) and polyethylenimine (PEI), which can generate mRNA (ovalbumin, a model antigen) and adjuvants (R848)-laden nanovaccines for at least 30 days after subcutaneous injection. The released nanovaccines can protect the mRNA from degradation and confer targeted delivering capacity to lymph nodes. The data show that this transformable hydrogel can significantly increase the number of antigen-specific CD8+ T cells and subsequently inhibit the tumor growth with only one treatment. Meanwhile, this hydrogel can generate an antigen specific antibody in the serum which in turn prevents the occurrence of metastasis. Collectively, these results demonstrate the potential of the PEI-functionalized GO transformable hydrogel for effective cancer immunotherapy.

Jinbao Liu,1 Xiaoyang Li,1 Liang Yue,2 Hao Lv2 1Department of Orthopaedics, The First Clinical Medical School, Shandong University of Traditional Chinese Medicine, Jinan 250011, People’s Republic of China; 2Department of Pediatric Orthopaedics, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan 250011, People’s Republic of ChinaCorrespondence: Hao LvDepartment of Pediatric Orthopaedics, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, No. 16369, Jinshi Road, Lixia District, Jinan 250011, People’s Republic of ChinaTel +86-531-68617091Email semon.lv@163.comBackground: Osteosarcoma (OS) is a common bone malignancy in children and adolescents. Circular RNAs (circRNAs) have been reported to affect OS progression. This paper mainly delineated the role of circRNA circ_0105346 in OS development and the potential mechanism.Methods: Quantitative reverse transcription PCR (qRT-PCR) and Western blot assays were applied to detect the expression of circ_0105346, microRNA (miR)-1182 and wingless-type MMTV integration site family 7B (WNT7B). 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was conducted to evaluate cell viability, and flow cytometry was performed to monitor cell apoptosis and cycle. In addition, cell migration and invasion were determined via transwell assay. Wound healing assay was also employed to evaluate the migrated capacity of OS cells. Western blot assay was also employed to examine the levels of protein markers. Additionally, the interaction between miR-1182 and circ_0105346 or WNT7B was confirmed by the dual-luciferase reporter, RNA immunoprecipitation (RIP) and pull-down assays. Mouse xenograft model was constructed to clarify the effect of circ_0105346 on tumor growth in vivo.Results: Circ_0105346 and WNT7B were upregulated, while miR-1182 was downregulated in OS tissues and cells. Circ_0105346 knockdown suppressed OS cell proliferation, cell cycle, migration, invasion and glycolysis, as well as accelerated apoptosis, which was attenuated by miR-1182 inhibition. Interestingly, circ_0105346 targeted miR-1182, and miR-1182 interacted with WNT7B. Circ_0105346 could upregulate WNT7B by downregulating miR-1182 expression. Furthermore, circ_0105346 knockdown blocked tumor growth in vivo.Conclusion: Circ_0105346 knockdown repressed OS progression by regulating miR-1182/WNT7B axis, at least in part.Keywords: osteosarcoma, circ_0105346, miR-1182, WNT7B, proliferation, apoptosis, metastasis, glycolysis

The effect of C-alloying on phase constituent, microstructure and mechanical behaviour of a novel Co-free (Fe36Mn36Ni9Cr9Al10)100-x C x (x = 0, 1.5, 2.5, 3.5, 5, 6) low-cost high entropy alloy (HEA...

Hypothesis G-quadruplex structure has raised increasing attention in supramolecular chemistry as an effective template for ordered functional materials. Thus, it is of practical significance to advance our understanding regarding G-quadruplex structures. Typically, G-quadruplex structures are formed in the presence of suitable metal ions. New methods to construct such structures need to be explored. Experiments The supramolecular assembly between CTAB and a guanosine derivative at different molar ratios was systematically studied, including assembly mechanisms, morphology, and macroscopic properties. Cationic surfactants with different alkyl chains were studied as control experiments. Findings A novel strategy to construct G-quadruplex with the promotion of the cationic surfactant CTAB is presented in this work. The structure-property relationships of G-quadruplex gels are characterized by rheology and shrinkage ratio experiments. MacKintosh’s theory was used to rationalize the relationship between gel elasticity and water content. The transition of G-quadruplex structures could be easily enabled by modulating CTAB concentration, which promotes the phase transition from gel/sol biphase to homogeneous sol phase. This work will provide a new viewpoint for the construction and modulation of G-quadruplex structures.

Cancer stem cell theory has been proposed to explain tumor heterogeneity and the carcinogenesis process. Highly tumorigenic lung cancer stem cells develop resistance to cisplatin (CDDP), a common chemotherapy drug. Herein, we attempted to clarify whether apigenin (API) can improve the antitumor efficiency of CDDP in lung cancer using cancer stem cells. Lung cancer stem cells were identified as CD 133 positive cancer cells in non-small cell lung cancer (NSCLC) A549, H1299 cells and CDDP-resistant NSCLC A549R cells. The cytotoxic effect of API was measured in CDDP-treated A549, H1299, and A549R cells. API repressed CD 133 positive cells and enhanced the antitumor effect of CDDP in A549, H1299, and A549R cells. The synergistic antitumor effect of API and CDDP was blocked by addition of the p53 inhibitor Pifithrin-α, and siRNA targeting the

In order to study the distribution behavior of hydrogen in metals under the condition of H2S corrosion, a layer-stripping micro-hardness test was designed to analyze the hydrogen distribution along the depth of hydrogen-charged 45 high-quality structural carbon steel at three different hydrogen sulfide concentrations and four corrosion periods in this study. The results show that there is a terminal solid solubility of hydrogen in the metal for hydrogen sulfide solutions over various concentrations and corrosion periods. A hydrogen-saturated layer is produced by hydrogen diffusing through the metal from an unsaturated state to a fully saturated state. The hydrogen-saturated layer is not affected by the concentration of the corrosion, but its thickness increases as the corrosion period increases. In this way, we established a new hydrogen diffusion model in metals.

Osteosarcoma (OS) is a common bone malignancy in children and adolescents. Circular RNAs (circRNAs) have been reported to affect OS progression. This paper mainly delineated the role of circRNA circ_0105346 in OS development and the potential mechanism.Quantitative reverse transcription PCR (qRT-PCR) and Western blot assays were applied to detect the expression of circ_0105346, microRNA (miR)-1182 and wingless-type MMTV integration site family 7B (WNT7B). 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was conducted to evaluate cell viability, and flow cytometry was performed to monitor cell apoptosis and cycle. In addition, cell migration and invasion were determined via transwell assay. Wound healing assay was also employed to evaluate the migrated capacity of OS cells. Western blot assay was also employed to examine the levels of protein markers. Additionally, the interaction between miR-1182 and circ_0105346 or WNT7B was confirmed by the dual-luciferase reporter, RNA immunoprecipitation (RIP) and pull-down assays. Mouse xenograft model was constructed to clarify the effect of circ_0105346 on tumor growth in vivo.Circ_0105346 and WNT7B were upregulated, while miR-1182 was downregulated in OS tissues and cells. Circ_0105346 knockdown suppressed OS cell proliferation, cell cycle, migration, invasion and glycolysis, as well as accelerated apoptosis, which was attenuated by miR-1182 inhibition. Interestingly, circ_0105346 targeted miR-1182, and miR-1182 interacted with WNT7B. Circ_0105346 could upregulate WNT7B by downregulating miR-1182 expression. Furthermore, circ_0105346 knockdown blocked tumor growth in vivo.Circ_0105346 knockdown repressed OS progression by regulating miR-1182/WNT7B axis, at least in part.

A simple and green approach is studied for the preparation of a high-activity metal-free N,O-codoped porous carbon (NOPC) electrocatalyst by one-step pyrolysis of pristine zinc-based zeolite-like metal-organic framework (Zn-ZMOF) synthesized by hydrothermal method from Zn2+and 4,5-imidazoledicarboxylic acid (H3IDC) in H2O solvent. It is found that the structure and electroactivity of Zn-ZMOF and NOPC vary with the molar ratio of H3IDC to zinc acetate. NOPC shows pH-universal electrocatalytic property for oxygen reduction reaction and its electrocatalytic performance is similar to that of Pt/C in alkaline and neutral electrolytes, and is close to that of Pt/C in acidic electrolyte, which is a relatively rare case for metal-free porous carbon derived from pristine MOF. Meanwhile, NOPC displays higher long-term stability and better tolerance to methanol and carbon monoxide poisoning than that of commercial Pt/C. The excellent performance of NOPC is mainly due to the special structure of the precursor Zn-ZMOF, and the synergism of abundant active sites, micro/mesoporous structure, large specific surface area, and high degree of graphitization.

Background::As the first phenylpyrazole pesticide, fipronil has been widely used in crop protection and public hygiene. In the low energy conformation of fipronil, a pseudo-six-membered ring is observed through an intramolecular hydrogen bond.Methods: :A scaffold hopping strategy was applied to mimic the pseudo-six-membered ring of fipronil by non-aromatic ring. All compounds were synthesized with a proper synthetic route and characterized by 1H NMR, 13C NMR and high-resolution mass spectra. Insecticidal activities of all target compounds against Plutella xylostella were assessed by a professional organization. Physicochemical property prediction and docking study of these compounds with GABA receptor were also performed.Results::A series of 1,4,6,7-tetrahydropyrazolo[3,4-d][1,3]oxazine derivatives containing twenty-five compounds were designed, synthesized and evaluated. Several compounds exhibited moderate activities against Plutella xylostella. The strong electron-withdrawing groups are conducive to improve activities of this series of compounds against Plutella xylostella. Docking study showed that the most active compound 10 with nitro group could bind within the TM2 domain of GABA receptor, in which a hydrogen bond was observed with residue 6’Thr. The activity of 10 was weaker than fipronil due to the differences in physicochemical properties.Conclusion: :More attention should be paid to physicochemical properties during novel pesticide hit or lead design through scaffold hopping.

The effects of gamma rays on two kinds of GaN high-electron-mobility transistors (HEMTs) have been investigated in this paper. We have identified a gate degradation using a combination of optical and electrical measurements. We have demonstrated that the channel current under the degradation position is outside of the gate’s control. This degradation prevents the gate from fully pinching off the channel, creating a current concentration region when applying a reverse gate voltage. An integrated analysis, including ${I}$ – ${V}$ characterization, the emission microscope (EMMI) technique, and temperature-dependent measurements, was applied to study its mechanism. It is attributed to an irradiation-induced degradation in the Schottky contact.

Apigenin (API) is a plant flavone that is known to exert a protective effect in rheumatoid arthritis (RA), which is a chronic autoimmune disease. However, the molecular mechanism for API's protective effect against RA is still unclear. Here, a collagen-induced arthritis (CIA) mouse model was used to assess the protective effect of API on RA. Histomorphological studies, immunohistochemistry, RT-PCR, and western blot were conducted to elucidate the roles of synovial hyperplasia, angiogenesis, and osteoclastogenesis in the protective effect of API on RA. Fibroblast-like synoviocytes (FLSs) were isolated to measure the effect of API on FLS proliferation and apoptosis. API exhibited a significant protective effect in CIA mice in a dose- and time-dependent manner. An increase in apoptosis and decrease in proliferation were observed after the API treatment in FLSs, suggesting that API might inhibit synovial hyperplasia. Moreover, CIA angiogenesis was repressed by API via down-regulation of VEGF and VEGFR. Furthermore, API regulated the osteoclastogenesis-associated RANKL/RANK/OPG system in CIA mice. Therefore, API inhibits CIA by repressing synovial hyperplasia, angiogenesis, and osteoclastogenesis. This suggested that API might be a putative low toxicity candidate drug for RA treatment.

Building a bridge between enzymatic and heterogeneous catalysis provides new cascade industrial processes for manufacturing. However, the reaction conditions of enzymatic and heterogeneous catalysis mutually cause deactivation of catalysts. Here, we overcame this challenge by developing a special protocol for the synthesis of hybrid catalysts. We utilized protein–polymer nanoconjugates as confined nanoreactors for the in situ synthesis of lipase–palladium (Pd) nanohybrids. The 0.8 nm Pd nanoparticles exhibited increased activity in racemization of (S)-1-phenylethylamine. At 55 °C, which matches the optimum temperature of lipase, the activity is more than 50 times that of commercial Pd/C. It was found that the Pd–O coordination in Pd subnanoclusters contributed to the high activity. In the dynamic kinetic resolutions of pharmaceutical intermediates (±)-1-phenylethylamine, (±)-1-aminoindan and (±)-1,2,3,4-tetrahydro-1-naphthylamine, the lipase–Pd nanohybrids displayed 7.6, 3.1 and 5.0 times higher efficiencies than the combination of commercial immobilized lipase Novozym 435 and Pd/C. The lipase–Pd nanohybrids can be reused without agglomeration and activity loss. Combining enzymatic and heterogeneous catalysts is challenging due to different reaction requirements. Here, a method is presented constructing single protein–polymer nanoconjugates as nanoreactors for the in situ synthesis of enzyme–metal nanohybrids with high activity at ambient conditions.

Herein we describe a highly chemoselective A3-coupling/annulation of amino alcohols, formaldehyde, two kinds of aldehydes and alkynes, catalyzed by copper(II). This cascade reaction, employing readily available materials, provides a new and highly effective access to chiral N-propargyl oxazolidines with good diastereoselectivity (up to >20:1). In the case of ortho-substituted aromatic aldehydes, an intriguing steric effect is observed: a bulky group exhibits a remarkably adverse effect on the diastereoselectivity for the formation of the title molecule.

Concurrent inhibition of Janus kinase (JAK) and histone deacetylase (HDAC) could potentially improve the efficacy of the HDAC inhibitors in the treatment of cancers and resolve the problem of HDAC inhibitor resistance in some tumors. Here, a novel series of pyrimidin-2-amino-pyrazol hydroxamate derivatives as JAK and HDAC dual inhibitors was designed, synthesized, and evaluated, among which 8m possessed potent and balanced activities against both JAK2 and HDAC6 with half-maximal inhibitory concentration at the nanomolar level. 8m exhibited improved antiproliferative and proapoptotic activities over SAHA and ruxolitinib in several hematological cell lines. Remarkably, 8m exhibited more potent antiproliferation effect than the combination of SAHA and ruxolitinib in HEL cells bearing JAK2V617F mutation. Pharmacokinetic studies in mice showed that 8m possessed good bioavailability after intraperitoneal administration. Finally, 8m showed antitumor efficacy with no significant toxicity in a HEL xenograft model....

Struvite crystallization is one of the most promising routes for phosphorus recovery from phosphorus-rich sludge. However, the adsorption of alginic acid, a surrogate of extracellular polymeric substances in phosphorus-rich sludge, on struvite crystals has been proved to significantly inhibit struvite crystallization. To comprehensively understand the inhibitory mechanism, the adsorption behavior was evaluated at various adsorption time, the concentration of alginic acid, pH and ionic strength in the present study. Subsequently, adsorption equilibrium isotherm, kinetic and thermodynamics models were employed to fit the adsorption data. Interestingly, the adsorption mechanism was explored by X-ray photoelectron spectra (XPS) and Fourier transform infrared spectroscopy analysis (FTIR), which was further elucidated by triple-layer model (TLM). The results indicated that the adsorption capacity of struvite crystals almost reached a plateau value within the first 30 min. Meanwhile, the adsorption capacity was significantly reduced with increasing pH, but slightly increased with increasing ionic strength. Moreover, the adsorption process obeyed pseudo-second order kinetic model and Langmuir adsorption isotherm model, whereas intra-particle diffusion was a main rate-limited step. Furthermore, hydrogen bonding and surface complexation between alginic acid and struvite crystals dominated the adsorption mechanism. Additionally, alginic acid underwent surface reactions by virtue of two outer-sphere surface complexes and one inner-sphere surface complex. The findings presented herein will facilitate understanding of the inhibitory mechanism of organic matters on struvite crystallization from phosphorus-rich sludge.

Hydrogels based on G-quadruplexes (G-hydrogels) were prepared using guanosine 5′-monophosphate disodium salt, GMP, with a hyperbranched poly(ethylenimine), PEI, containing abundant –NH2 groups. The cation–dipolar interaction between Na+ ions and GMP-quartets and the hydrogen bonding between the phosphate groups of GMP and the –NH2 groups of PEI gave rise to the hydrogels at an appropriate pH range of 1.7–4.3. X-ray diffraction (XRD) measurements and fluorescence enhancement of Thioflavin T (ThT) indicated the formation of the G-quadruplexes. The G-hydrogel showed high adsorption capacity for the contaminant, picric acid (PA), in water, ascribed to its plentiful –NH2 groups in the network structures.

Biomimetic strategies have successfully been applied to confine multiple enzymes on scaffolds to obtain higher catalytic efficiency of enzyme cascades than freely distributed enzymes. However, the origin of high efficiency is poorly understood. We developed a coarse-grained, particle-based model to understand the origin of high efficiency. We found that a reaction intermediate is the key in affecting reaction kinetics. In the case of unstable intermediates, the confinement of multiple enzymes in clusters enhanced the catalytic efficiency and a shorter distance between enzymes resulted in a higher reaction rate and yield. This understanding was verified by co-encapsulating multiple enzymes in metal-organic framework (MOF) nanocrystals as artificially confined multienzyme complexes. The activity enhancement of multiple enzymes in MOFs depended on the distance between enzymes, when the decay of intermediates existed. The finding of this study is useful for designing in vitro synthetic biology systems based on artificial multienzyme complexes.

Enzymatic catalysis, which has been driving biological processes in a green, mild, and efficient manner for billions of years, is increasingly being used in industrial processes to manufacture chemicals, pharmaceuticals, and materials for human society. Since enzymes were discovered, strategies to adapt enzymes for use as catalysts for industrial processes, such as chemical modification, immobilization, site-directed mutagenesis, directed evolution of enzymes, artificial metalloenzymes, and computational design, have been continuously pursued. In contrast to these strategies, editing enzymes to easily integrate biocatalysis with chemocatalysis is a potential way to apply enzymes in industry. Enzyme catalyst editing focuses on fine-tuning the microenvironment surrounding the enzyme or achieving a new catalytic function to construct better biocatalysis under non-natural conditions for the enzyme.

Hemangiomas, also called infantile hemangiomas (IH), are the most common congenital benign vascular tumors in infants and young children. At present, there are many treatment methods for proliferative hemangiomas, which have different effects and lack predictability. Propranolol has gradually replaced glucocorticoids as the first-line treatment for infants and young children with hemangiomas. However, premature discontinuation is prone to relapse, and the efficacy and safety of medication need to be further studied and determined. The exact pathogenesis of hemangiomas is still unclear. Therefore, in this study, poly(lactic-co-glycolic acid) (PLGA) nanoparticles were used as drug delivery carriers, propranolol was encapsulated, and PLGA-propranolol (PLGA-PP) nanodelivery preparations were prepared and targeted. Anisotropy and pharmacokinetics were preliminary studied. At the same time, after the treatment of HemECs cells with PLGA-PP in gradient concentration in vitro, CCK-8 method was used to detect the cell proliferation, and Anyixin-V/PI double staining method was used to detect the apoptosis rate of cells. The effect of PLGA-PP nano-delivery vector on hemangioma was studied by western blot method to detect the expression level of Id-1 protein in HemECs. The results showed that after PLGA-PP treated HemECs for 24 h, PLGA-PP significantly inhibited HeECs proliferation and promoted their apoptosis, and the intracellular Id-1 protein expression was also reduced. Therefore, this study believes that the mechanism of PLGA-PP nano-targeted delivery preparations in the treatment of hemangiomas is achieved by down-regulating the Id-1 gene, thereby inhibiting the colonization of HemECs and promoting its apoptosis effect.

Agrobacterium tumefaciens is the causal agent of crown gall disease. The bacterium is capable of transferring a segment of single-stranded DNA (ssDNA) into recipient cells during the transformation process, and it has been widely used as a genetic modification tool for plants and nonplant organisms. Transferred DNA (T-DNA) has been proposed to be escorted by two virulence proteins, VirD2 and VirE2, as a nucleoprotein complex (T-complex) that targets the host nucleus. However, it is not clear how such a proposed large DNA-protein complex is delivered through the host nuclear pore in a natural setting. Here, we studied the natural nuclear import of the Agrobacterium-delivered ssDNA-binding protein VirE2 inside plant cells by using a split-GFP approach with a newly constructed T-DNA-free strain. Our results demonstrate that VirE2 is targeted into the host nucleus in a VirD2- and T-DNA-dependent manner. In contrast with VirD2 that binds to plant importin α for nuclear import, VirE2 directly interacts with the host nuclear pore complex component nucleoporin CG1 to facilitate its nuclear uptake and the transformation process. Our data suggest a cooperative nuclear import model in which T-DNA is guided to the host nuclear pore by VirD2 and passes through the pore with the assistance of interactions between VirE2 and host nucleoporin CG1. We hypothesize that this large linear nucleoprotein complex (T-complex) is targeted to the nucleus by a "head" guide from the VirD2-importin interaction and into the nucleus by a lateral assistance from the VirE2-nucleoporin interaction.

Mitochondria are potential targets for the treatment of cardio-cerebrovascular ischemia–reperfusion (I/R) injury. However, the role of the mitofusin 2 (Mfn2) protein in regulating mitochondrial fusion and cell survival has not been investigated. In the present study, an adenovirus-mediated Mfn2 overexpression assay was performed to understand the effects of Mfn2 on mitochondrial function and cell damage during cardio-cerebrovascular I/R injury. After exposure to I/R injury in vitro, the transcription and expression of Mfn2 were significantly downregulated, which correlated with decreased cell viability and increased apoptosis. By contrast, overexpression of Mfn2 significantly repressed I/R-mediated cell death through modulation of glucose metabolism and oxidative stress. Furthermore, Mfn2 overexpression improved mitochondrial fusion in cells, an effect that was followed by increased mitochondrial membrane potential, improved mitophagy, and inhibition of mitochondria-mediated apoptosis. Our data also demonstrated that Mfn2 overexpression was associated with activation of the AMPK/Sirt3 signaling pathway. Inhibition of the AMPK/Sirt3 pathway abolished the protective effects of Mfn2 on I/R-induced cell injury arising from mitochondrial damage. Our results indicate that Mfn2 protects against cardio-cerebrovascular I/R injury by augmenting mitochondrial fusion and activating the AMPK/Sirt3 signaling pathway.

Background:Ataxia-telangiectasia and Rad3 related protein kinase (ATR) is an essential regulator of the DNA damage response in various cancers; however, its expression and roles in osteosarcoma are unclear. We therefore chose to evaluate the significance and mechanism of ATR in metastatic osteosarcoma, as well as its potential to be a therapeutic target.Methods:The osteosarcoma tissue microarrays constructed from 70 patient specimens underwent immunohistochemistry to quantify ATR and activated phospho-ATR (pATR) expression and their correlation with clinical outcomes. ATR sublocalization within the metastatic osteosarcoma cells was confirmed by immunofluorescence assay. Cell proliferation, apoptosis, and migration were evaluated following treatment with ATR siRNA or the selective inhibitor Berzosertib. Antitumor effects were determined with ex vivo three-dimensional (3D) culture models, and the impacts on the DNA damage repair pathways were measured with Western blotting.Results:Elevated ATR and activated pATR expression correlated with shorter patient survival and less necrosis following neoadjuvant chemotherapy. Intranuclear sublocalization of ATR and pATR suggested a mechanism related to DNA replication. ATR knockdown with siRNA or inhibition with Berzosertib suppressed cell proliferation in a time- and dose-dependent manner and induced apoptosis. In addition, ATR inhibition decreased Chk1 phosphorylation while increasing γH2AX expression and PARP cleavage, consistent with the interference of DNA damage repair. The ATR inhibitor Berzosertib also produced the characteristic cytoplasmic vacuolization preceding cell death, and suppressed ex vivo 3D spheroid formation and cell motility.Conclusion:The faithful dependence of cells on ATR signaling for survival and progression makes it an emerging therapeutic target in metastatic osteosarcoma.

Motif analysis on evolutionarily conserved regions in laminin enabled the discovery of novel ligands for hydrogel development., Biologically active ligands (e.g., RGDS from fibronectin) play critical roles in the development of chemically defined biomaterials. However, recent decades have shown only limited progress in discovering novel extracellular matrix–protein–derived ligands for translational applications. Through motif analysis of evolutionarily conserved RGD-containing regions in laminin (LM) and peptide-functionalized hydrogel microarray screening, we identified a peptide (a1) that showed superior supports for endothelial cell (EC) functions. Mechanistic studies attributed the results to the capacity of a1 engaging both LM- and Fn-binding integrins. RNA sequencing of ECs in a1-functionalized hydrogels showed ~60% similarities with Matrigel in “vasculature development” gene ontology terms. Vasculogenesis assays revealed the capacity of a1-formulated hydrogels to improve EC network formation. Injectable alginates functionalized with a1 and MMPQK (a vascular endothelial growth factor–mimetic peptide with a matrix metalloproteinase–degradable linker) increased blood perfusion and functional recovery over decellularized extracellular matrix and (RGDS + MMPQK)–functionalized hydrogels in an ischemic hindlimb model, illustrating the power of this approach.

Despite the availability of more than 25 antiseizure drugs on the market, approximately 30% of patients with epilepsy still suffer from seizures. Thus, the epilepsy therapy market has a great need for a breakthrough drug that will aid pharmacoresistant patients. In our previous study, we discovered a vitamin K analogue, 2h, which displayed modest antiseizure activity in zebrafish and mouse seizure models. However, there are limitations to this compound due to its pharmacokinetic profile. In this study, we develop a new series of vitamin K analogues by modifying the structure of 2h. Among these, compound 3d shows full protection in a rodent pharmacoresistant seizure model with limited rotarod motor toxicity and favorable pharmacokinetic properties. Furthermore, the brain/plasma concentration ratio of 3d indicates its excellent permeability into the brain. The resulting data shows that 3d can be further developed as a potential antiseizure drug in the clinic.

Here, we present a new series of hydrazide-bearing class I selective HDAC inhibitors designed based on panobinostat. The cap, linker, and zinc-binding group were derivatized to improve HDAC affinity and antileukemia efficacy. Lead inhibitor 13a shows picomolar or low nanomolar IC50 values against HDAC1 and HDAC3 and exhibits differential toxicity profiles toward multiple cancer cells with different FLT3 and p53 statuses. 13a indirectly inhibits the FLT3 signaling pathway and down-regulates master antiapoptotic proteins, resulting in the activation of pro-caspase3 in wt-p53 FLT3-ITD MV4-11 cells. While in the wt-FLT3 and p53-null cells, 13a is incapable of causing apoptosis at a therapeutic concentration. The MDM2 antagonist and the proteasome inhibitor promote 13a-triggered apoptosis by preventing p53 degradation. Furthermore, we demonstrate that apoptosis rather than autophagy is the key contributing factor for 13a-triggered cell death. When compared to panobinostat, 13a is not mutagenic and displays superior in vivo bioavailability and a higher AUC0-inf value.

Agrobacterium tumefaciens is the causal agent of crown gall disease in nature; in the laboratory the bacterium is widely used for plant genetic modification. The bacterium delivers a single-stranded transferred DNA (T-DNA) and a group of crucial virulence proteins into host cells. A putative T-complex is formed inside host cells that is composed of T-DNA and virulence proteins VirD2 and VirE2, which protect the foreign DNA from degradation and guide its way into the host nucleus. However, little is known about how the T-complex is assembled inside host cells. We combined the split-GFP and split-sfCherry labeling systems to study the interaction of Agrobacterium-delivered VirE2 and VirE3 in host cells. Our results indicated that VirE2 co-localized with VirE3 on the cytoplasmic side of the host cellular membrane upon the delivery. We identified and characterized two tandem domains at the VirE3 C-terminus that interacted with VirE2 in vitro. Deletion of these two domains abolished the VirE2 accumulation on the host plasma membrane and affected the transformation. Furthermore, the two VirE2-interacting domains of VirE3 exhibited different affinities with VirE2. Collectively, this study demonstrates that the anchorage protein VirE3 uses the two tandem VirE2-interacting domains to facilitate VirE2 protection for T-DNA at the cytoplasmic side of the host cell entrance.

Histone deacetylases (HDACs) have been indicated important roles in neurodegenerative disorders including Alzheimer’s disease (AD). Herein, a series of novel compounds that contain a memantine moiety were designed to target HDACs and N-methyl- d -aspartate receptor (NMDAR) which are related to the treatment of AD. Biological characterization established that compound 9d exhibited a balanced inhibitory activity on NMDAR and HDACs. This compound is relatively selective to HDAC6 with IC50 of 0.18 μM and also maintains comparable activity on NMDAR (Ki = 0.59 μM) as memantine. Functionally, treatment with 9d increased the level of AcTubulin in MV4-11 cells and rescued PC-12 cells from H2O2-induced cytotoxicity with EC50 of 0.94 μM. Studies in mice also demonstrated that compound 9d efficiently penetrates the blood brain barrier to reach the brain tissue. Collectively, the results strongly encourage further development of 9d as a potential therapeutic agent for AD.

In this paper, we provide a novel type of micro-direct methanol fuel cell (μDMFC) fabricated with two stainless steel plates as metal current collectors. In order to improve cell performance, two sheets of stainless steel mesh (SSM) are added between the membrane electrode assembly (MEA) and current collectors. To avoid electrochemical corrosion, titanium nitride (TiN) layers with thickness of 500 nm are deposited onto the surface of current collectors and stainless steel mesh. The results show that the embedded stainless steel mesh can remarkably reduce the interior impedance of the μDMFC. Moreover, compared with μDMFC without SSM, the novel cell exhibits a more outstanding performance, yielding a maximum power density of 54.4 mW cm−2 at 80 °C.

The amphiphilic derivatives of l -histidine with different alkyl chains, NIPCA, UIPCA, and TIPCA, have been designed and their self-assembly behaviors with citric acid were investigated. All l -histidine derivatives can form hydrogels with citric acid, and exhibit the increasing gelation ability and mechanical strength with the increasing chain length. The gelation ability is considered to be affected by the synergistic effect of electrostatic interaction, hydrogen bonding and hydrophobic interaction. The hydrogels exhibit excellent releasing selectivity for charged dyes in aqueous solution, enlightening people to utilize this kind of hydrogels as intelligent carriers to separate the mixtures of charged dyes.

Previously, we designed and synthesized a series of o-aminobenzamide-based histone deacetylase (HDAC) inhibitors, among which the representative compound 11a exhibited potent inhibitory activity against class I HDACs. In this study, we report the development of more potent hydrazide-based class I selective HDAC inhibitors using 11a as a lead. Representative compound 13b showed a mixed, slow, and tight binding inhibition mechanism for HDAC1, 2, and 3. The most potent compound 13e exhibited low nanomolar IC(50)s toward HDAC1, 2, and 3 and could down-regulate HDAC6 in acute myeloid leukemia MV4-11 cells. The EC(50) of 13e against MV4-11 cells was 34.7 nM, which is 26 times lower than its parent compound 11a. In vitro responses to 13e vary significantly and interestingly based on cell type: in p53 wild-type MV4-11 cells, 13e induced cell death via apoptosis and G1/S cell cycle arrest, which is likely mediated by a p53-dependent pathway, while in p53-null PC-3 cells, 13e caused G2/M arrest and inhibited cell proliferation without inducing caspase-3-dependent apoptosis.

This work describes the gelation behaviors and properties of a biological molecule, guanosine 5′-monophosphate disodium salt (GMP), in the presence of trivalent lanthanide ions. Hydrogels composed of GMP-quadruplexes were prepared by adjusting pH, through which the protonation of phosphate group was controlled to tune the interactions between lanthanide ions and GMP. Within the pH region of 2–6, the electrostatic interaction between lanthanide ions and phosphate group is hindered and the cation-dipole interaction acts as the main driving force for the formation of G-quadruplexes. All the hydrogels were found consisting of three-dimensional network of the intertwining one-dimensional nanofibers formed by the stacking G-quartets induced by lanthanide ions. A significant fluorescence enhancement of thioflavin T (ThT), a fluorescent molecule, was found to be triggered by the G-quadruplex structures, for which the rotation of chromophoric groups on ThT molecules were prohibited due to the implant into the G-quadruplex structures.

Irradiation to developing brains results in progressive cognitive dysfunction. Changes in the morphology of mature neurons are thought to be related to impairments of cognitive function. However, little is known about the effects of radiation on neurite outgrowth of immature neurons. Therefore, we sought to evaluate the structural alterations of immature neurons following X-ray irradiation and determine potential strategies to reverse it. Our data revealed damage to the neurite outgrowths of cultured neurons after 2 Gy and 8 Gy irradiation at 1 d and 3 d, respectively. De-phosphorylation of nuclear factor of activated T-cells c4/3 (NFATc4/3) was inhibited post-irradiation. Extraneous brain-derived neurotrophic factor (BDNF) ameliorated impairment of neurite growth and activated the NFATc4/3 signaling pathway. These data indicate that BDNF confers neuroprotective effects against irradiation by modulating the NFATc4/3 pathway.