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Plants comprise an expanded endomembrane system, and transport within the network requires well-organized and accurate vesicle transport. Tethering complexes facilitate the early, exact contact among donor and acceptor membranes, operate to bring vesicles into a closer proximity for trans-SNARE complex assembly docking; these are classified as either long coiled-coil proteins or multi-subunit tethering complexes (MTCs). Numerous MTCs that function at different membrane trafficking steps have been recognized, where they function as significant interfaces between SNARE proteins, Rabs, and phosphoinositides. SNARE proteins assemble into complexes that catalyze the fusion between a donor and a target membrane. Studies of the diverse SNARE proteins provided further valuable information about vacuole biogenesis and vacuolar trafficking pathways related to cell-type specificity, plant development, growth, and the plant developed a specific traffic route to overcome environmental stress. In conclusion, tethers' selective recruitment during membrane fusion is controlled via diverse small GTPases, such as those in the RAB family. The MTCs promote SNARE complex assembly by direct interactions of MTC subunits with Q-SNAREs. A subset of MTC subunits exploits structurally similar CATCHR domains to mediate inter-subunit interactions as well as SNARE protein interactions. MTCs are subdivided into CATCHR (complexes associated with tethering containing helical rods: Dsl1, COG, GARP, EARP, and exocyst) and non‐CATCHR (TRAPP I, II and III, HOPS and CORVET) complexes based on the structure of their subunits. This review summarized new information about SNARE proteins and tethering complexes, highlight new insights about their function, and discuss current debates and future perspectives.

In eukaryotes, N‐ethylmaleimide‐sensitive factor (NSF) is a conserved AAA+ATPase and a key component of the membrane trafficking machinery that promotes the fusion of secretory vesicles with target membranes. Here, we demonstrate that the Arabidopsis thaliana genome contains a single copy of NSF, AtNSF, which plays an essential role in the regulation of leaf serration. The AtNSF knock‐down mutant, atnsf‐1, exhibited more serrations in the leaf margin. Moreover, polar localization of the PIN‐FORMED1 (PIN1) auxin efflux transporter was diffuse around the margins of atnsf‐1 leaves and root growth was inhibited in the atnsf‐1 mutant. More PIN1‐GFP accumulated in the intracellular compartments of atnsf‐1 plants, suggesting that AtNSF is required for intracellular trafficking of PIN between the endosome and plasma membrane. Furthermore, the serration phenotype was suppressed in the atnsf‐1 pin1‐8 double mutant, suggesting that AtNSF is required for PIN1‐mediated polar auxin transport to regulate leaf serration. The CUP‐SHAPED COTYLEDON2 (CUC2) transcription factor gene is up‐regulated in atnsf‐1 plants and the cuc2‐3 single mutant exhibits smooth leaf margins, demonstrating that AtNSF also functions in the CUC2 pathway. Our results reveal that AtNSF regulates the PIN1‐generated auxin maxima with a CUC2‐mediated feedback loop to control leaf serration., N‐ethylmaleimide‐sensitive factor (NSF) promotes the fusion of secretory vesicles in eukaryotes. In Arabidopsis, AtNSF negatively regulates leaf serration by affecting trafficking of the PIN‐FORMED1 auxin transporter and interfering with the PIN‐FORMED1 and CUP‐SHAPED COTYLEDON2‐mediated feedback loop for leaf serration.

A three high planetary mill is used to produce bismuth-containing stainless-steel bars with high production efficiency. However, due to the influence of bismuth metal properties, the selection of processing parameters must be optimized to avoid the generation of cracking in the bar core. To solve this contradiction and find a suitable processing zone, the thermal simulation experiment of bismuth-containing stainless-steel material was carried out first to determine the constitutive relationship of the material. Three-roll planetary rolling experiments were carried out to determine the crack-producing region. Based on the Brozzo ductile fracture criterion, the fracture threshold of bismuth-containing austenitic stainless-steel bars in three-roll planetary rolling was determined by the finite element (FE) simulation. Five key process parameters were selected, with five factors and four levels of the orthogonal test designed. Through FE simulations, the possibility of cracking of stainless-steel bars with bismuth austenites in different technologic conditions was judged, and a set of optimal technologic parameters was obtained. Based on range analysis, the influence of various process parameters on bar cracking was discussed. Then, based on the dynamic material model and Murty criterion, the processing map of free-cutting austenitic stainless containing bismuth was established. It was found that the optimum process parameters were consistent with the processable range of the hot-working chart. Finally, the field rolling was carried out with the optimum process parameters, showing that there was no crack in the bar.

In order to improve the tribological properties of zinc-based alloy, SiC nanoparticles (an average grain size of 100 nm) were reinforced into Zn–38Al–3.5Cu–1.2 Mg alloy through a high-pressure jetting powder and semisolid stirring-assisted ultrasonic vibration process. In the present study, the effects of different SiC contents (0 wt%, 0.07 wt%, 0.13 wt%, and 0.22 wt%) on microstructural properties and wear behavior of the as-cast alloy were investigated in detail. The results indicated that a uniform and dispersive distribution of SiC nanoparticles was observed in the Zn–Al matrix, thus leading to a significant enhancement in wear behavior of Zn–38Al–3.5Cu–1.2 Mg alloy. Further, with the increasing mass fraction of SiC nanoparticles, wear resistance of Zn–38Al–3.5Cu–1.2 Mg alloy was noticeably improved in spite of the increasing friction temperature. The increased wear resistance of Zn–38Al–3.5Cu–1.2 Mg alloy at high friction temperature could be attributed to the presence of uniformly dispersed thermostable SiC nanoparticles, which inhibited the transformation of the abrasion-resistant phase of α + η mixture to the soft phase of α and η on the friction heating interface.

Objectives The immune status of the tumor microenvironment has a marked impact on clinical outcomes. Here we examined the immune environments of tumor-infiltrating leukocytes (TILes) in two murine models of squamous cell carcinoma and compared the effects of immunotherapeutic agents, including a TLR7 agonist and an immune checkpoint inhibitor, and a chemotherapeutic agent, gemcitabine, in these models. Materials and methods TILes from NR-S1- and SCCVII-grafted mice were analyzed by flow cytometry. NR-S1-inoculated mice received resiquimod (a synthetic TLR7 agonist), an anti-PD-L1 antibody, or both, and tumor growth and TILs were examined. Gemcitabine was administered to deplete CD11b+ cells. Results More than 50% of TILes from NR-S1- and SCCVII-inoculated mice were CD11b+Gr-1+ cells. A major fraction of NR-S1 CD11b+ cells was Ly6GhighLy6Clow-negaF4/80− tumor-associated neutrophils (TANs) and the majority of SCCVII CD11b+ cells were Ly6GlowLy6C−F4/80+ tumor-associated macrophages. NR-S1 TANs did not express MHC class II and CD86, but did express reactive oxygen species and PD-L1. Resiquimod, alone and in combination with an anti-PD-L1 antibody, did not regress NR-S1 tumors, but the combination increased the CD8/regulatory T cell-ratio, and IFN-γ and PD-1 expression in CD8+ TILes. Pre-administration of low-dose gemcitabine prior to the combination treatment suppressed the progression of NR-S1 tumors. Conclusions NR-S1 tumors with abundant recruitment of TANs were resistant to treatments with a TLR7 agonist, alone and in combination with PD-1 blockade, and required an additional gemcitabine treatment. The phenotype and status of tumor-infiltrating CD11b+ myeloid cells may influence the efficacy of immunotherapeutic agents.

The plant cytoskeleton forms a stereoscopic network that regulates cell morphogenesis. The cytoskeleton also provides tracks for trafficking of vesicles to the target membrane. Fusion of vesicles with the target membrane is promoted by SNARE proteins, etc. The vesicle-SNARE, Sec22, regulates membrane trafficking between the ER and Golgi in yeast and mammals. Arabidopsis AtSEC22 might also regulate early secretion and is essential for gametophyte development. However, the role of AtSEC22 in plant development is unclear. To clarify the role of AtSEC22 in the regulation of plant development, we isolated an AtSEC22 knock-down mutant, atsec22-4, and found that cell morphogenesis and development were seriously disturbed. atsec22-4 exhibited shorter primary roots (PRs), dwarf plants, and partial abortion. More interestingly, the atsec22-4 mutant had less trichomes with altered morphology, irregular stomata, and pavement cells, suggesting that cell morphogenesis was perturbed. Further analyses revealed that in atsec22-4, vesicle trafficking was blocked, resulting in the trapping of proteins in the ER and collapse of structures of the ER and Golgi apparatus. Furthermore, AtSEC22 defects resulted in impaired organization and stability of the cytoskeleton in atsec22-4. Our findings revealed essential roles of AtSEC22 in membrane trafficking and cytoskeleton dynamics during plant development.

Research on immune checkpoint blockade therapy has made great progress in cancer immunotherapy, but the number of patients who benefit from this therapy remains limited. In this study, we examined the effects of monotherapy with systemic low-dose resiquimod, a synthesized TLR7 agonist, and examined its combined effects with PD-L1 blockade in two PD-L1 blockade-resistant tumor models (SCCVII and Colon 26). Resiquimod monotherapy in SCCVII tumors, representing impaired CD8+ T cell function and accelerated regulatory T cells (Tregs) within the tumors, efficiently reduced tumor growth with more recruitment of CD8+ T cells and a reduction of Treg. The results of resiquimod monotherapy in Colon 26, representing impaired Treg recruitment, were inferior to that in SCCVII. Combined resiquimod treatment with PD-L1 blockade exerted clear additional effects, as it was associated with reduced tumor size, attenuation of Tregs, and an increased ratio of CD8+ T cells/Tregs in both tumors. Systemic administration of low-dose resiquimod induced a transient and rapid activation of plasmacytoid and conventional dendritic cells, resulting in enhanced priming of T cells in regional lymph nodes. Experiments with more limited doses of resiquimod that did not yield beneficial effects after single treatment, showed additional effects to PD-L1 blockade and comparable antitumor effects when the frequency of anti-PD-L1 therapy was decreased. Our results suggest that systemic administration of low-dose resiquimod is useful as a companion drug to PD-1/PD-L1 blockade therapy.

This study investigated the effects of a CoCl2-simulated hypoxic environment on the muscle fiber switching signaling pathways calcineurin A/nuclear factor of activated T cells cytoplasmic 1 (CnA/NFATc1) and myostatin. In this study, C2C12 muscle cells were cultured in vitro under CoCl2-simulated chemical hypoxic conditions, the expression levels of CnA and myostatin were detected through qRT-PCR and Western blot analyses, and a positioning study of NFATc1 was carried out by immunofluorescence labeling. Results showed that CoCl2 treatment significantly increased the expression levels of CnA and myostatin. Moreover, the position of NFATc1 expression changed; actually, its expression in the nucleus considerably increased. Furthermore, CoCl2-induced hypoxia inhibited the differentiation of C2C12 cells and reduced the expression levels of many slow- and fast-twitch muscles marker genes, but immunofluorescence staining results showed that the proportion of MyHC I type muscle fiber increased after CoCl2 treatment. The hypoxic environment simulated by CoCl2 can activate the signaling pathways CnA/NFATc1 and myostatin and increases the proportion of MyHC I type muscle fibers.

A series of novel saccharin derivatives containing 1,2,3-triazole moiety was synthesized in satisfactory yields. The structures of all the compounds were elucidated and confirmed by Fourier transform infrared(FTIR) spectroscopy, 1H and 13C nuclear magnetic resonance(1H NMR, 13C NMR) spectroscopy, and high resolution mass spectrometry(HRMS). The bioassays indicated that most of the title compounds displayed some extent herbicidal activities at 100 μg/mL.

Captopril is a New Delhi metallo-β-lactamase-1 (NDM-1) inhibitor with an IC50 value of 7.9μM. It is composed of two units: a 3-mercapto-2-methylpropanoyl fragment and a proline residue. In this study, we synthesized simple amide derivatives of 3-mercapto-2-methylpropanoic acid, and then tested them as NDM-1 inhibitors in order to identify the pharmacophore for NDM-1 inhibition. We found that the lead compound 22 had an IC50 value of 1.0μM. Further structure simplification provided compounds 31 and 32, which had IC50 values of 15 and 10μM, respectively. As compound 32 is a clinically used antidote for metal poisoning, it has great potential to be repurposed to treat bacterial infections.

An economic microalgae Haematococcus pluvialis CH-1 was used as experimental material. An experiment of adding six grades of concentrations of Vitamin-B12 and Vitamin-H respectively was conducted. Cell density, biomass and astaxanthin content were measured. The results showed that the growth of H. pluvialis was accelerated significantly by adding of Vitamin-B12 and Vitamin-H, respectively. The optimal adding concentration of Vitamin-B12 and Vitamin-H respectively for H. pluvialis was 50 and 500 µg/L. Under the optimal concentration for H. pluvialis, cells density, biomass and astaxanthin content were enhanced with Vitamin-B12: 29.5, 30.0 and 28.3%; Vitamin-H: 17.1, 29.2 and 22.6% higher than the blank, respectively. On the mass culture of motile cells of H. pluvialis, properly adding Vitamin-B12 and Vitamin-H, respectively was effective for increase cells density, biomass and astaxanthin content.

In recent years, low dose cyclophosphamide has been used clinically either as a single agent or as combination therapy to treat lymphomas, and breast and ovarian cancers. The efficacy of low dose cyclophosphamide is primarily due to its ability to immune-modulate in addition to its direct anti-tumor effects. This ability highlights the potential for synergism between conventional chemotherapy and novel immunotherapy. Toll-like receptors (TLRs) are a crucial part of the innate immunity and present the first line of defense against pathogens. Resiquimod is the ligand for TLR7 and 8 and directly activate innate immune cells, including myeloid dendritic cells, plasmacytoid dendritic cells, and monocytes/macrophages. This activation may result in activation of co-stimulatory molecules, production of antiviral cytokines, and stimulation of cell-mediated NK and T cell immune responses. The aim of this study was to analyze whether immunopotentiating TLR7/8 agonist might synergize with low doses of cyclophosphamide in the treatment of colorectal carcinoma. The effect of combining a weekly dosing of cyclophosphamide intraperitoneally with systemic administration of Resiquimod was evaluated in an in vivo murine C26 synergistic model. Systemic administration of Resiquimod in mice induced significant systemic immune responses as evidenced by upregulating IFNα inducible gene clusters. The combined therapy with Resiquimod and cyclophosphamide was superior to each single treatment and increased efficacy of tumor inhibition and prolonged their survival significantly. Importantly, the combined treatment generated a significant numbers of tumor-specific T cell infiltration in tumor microenvironment. Our data suggest that systemic administration of TLR7/8 agonist enhances anti-tumor effect of low dose of cyclophosphamide. The data supports the use of a combination of TLR7/8 agonist and cyclophosphamide as a novel therapeutic strategy against colorectal carcinoma. Citation Format: Jing Yang, Patrick Z. Li, Xiangyun Yin, Xiaohua Nie, Jingshu Wang, Walter Lau, Liguo Zhang, Lixin Li. Synergistic immunotherapeutic effects of TLR7/8 agonist on low-dose cyclophosphamide-treated C26 model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2746.

Mass spectrometry-based platforms have gained increasing success in discovery of ligands bound to therapeutic targets as drug candidates. We established both a nanoelectrospray ionization mass spectrometry (nanoESI-MS) assay and an ultrafiltration liquid chromatography/mass spectrometry (LC/MS) assay to identify new ligands for New Delhi metallo-β-lactamase 1 (NDM-1), responsible for worldwide antibiotic resistance. To alleviate nonspecific binding of hydrophobic compounds and eliminate false positives typically encountered in the indirect LC/MS-based assay, we introduced a blocking protein in the control, which remarkably enhances the selectivity and accuracy of the indirect approach. Side-by-side comparison of the two MS-based approaches for the first time further reveals unique advantages of the indirect approach, including better reproducibility and tolerance of interference. Moreover, the success of fishing out a potent ligand from a mixture of small-molecule fragments demonstrates great potential of the indirect LC/MS-based approach for constructing a robust screening platform against combinatorial libraries or natural product extracts. More importantly, by combining the results of MS-based analyses, enzymatic activity assay, competition experiments, and structural simulation, we discovered a new compound as a promising drug candidate targeting NDM-1.

[Aim] Toll like receptor (TLRs) are expressed in many types of immune cells and function as a key sensor of microbial products. Ligand binding to TLRs leads to activation of signaling pathways in innate immune cells, particularly dendritic cells and subsequent induction of adaptive immune responses. TLR7/8 agonists have been shown to enhance antiviral and antitumor immune responses via multiple cytokine production such as IFN-α, IL-1β, IL-6 and TNFα. Resiquimod (R-848) is a synthetic imidazoquinoline-like molecule that binds to TLR7 and TLR8. Presently, resiquimod has been used as a topical drug for skin cancer and viral infection, because of severe side effects of systemic administration. Thus far, the clinical results of anti-PD-1 or anti-PD-L1 therapy have showed great benefits by inducing tumor regression and improving survival. However, the patients obtained the benefits of this treatment are around one third. An additional approach is required to enhance the efficacy of PD-1 blockade therapy. In this study, we examined the effects of combined treatment with anti-PD-L1 antibody and a low dose of resiquimod administration in two murine tumor models (a squamous cell carcinoma cell line, SCCVII and a colon carcinoma cell line, Colon26). [Methods] Anti-PD-L1 mAb (MIH5, 200 μg/mouse) and/or resiquimod (1.73 μg/mouse) were intraperitonealy administrated at three times a week and tumor growth was evaluated. [Results and Discussion] In a Colon26 model, either anti-PD-L1 (MIH5) mAb or resiquimod treatment alone slightly decreased tumor growth, but the combined treatment dramatically reduced the tumor growth and completely eradicated the tumor in some of mice. In a SCCVII model, monotherapy with resiquimod markedly reduced the tumor growth and completely eradicated the tumor in some of mice. The combined treatment further enhanced the efficacy. The delayed combined treatment at day 7 also showed the reduction of tumor size. Functional analyses at 3-4 wks after the tumor inoculation revealed that monotherapy with resiquimod in the SCCVII model and the combined treatment in both models significantly enhanced the percentages of IFN-γ+-expressing CD8+ T cells, but did not clearly affect the percentages of Foxp3+ regulatory T cells. Our results suggest that TLR7/8 agonist administration alone markedly enhanced antitumor responses in a selected tumor model and the combined treatment with PD-L1 blockade and a TLR7/8 agonist further amplify their effects. Citation Format: Naoto Nishii, Yuta Kondo, Lixin Li, Walter Lau, Hiroyuki Harada, Miyuki Azuma. Combined treatment with PD-L1 blockade and a TLR7/8 agonist dramatically enhances antitumor immunity. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 563.

Qilu Petrochemical Co. Ltd developed a soft measurement technique based on a neural network and implemented the computer online inferential control to control the propane and propylene consistency in the propylene rectification column.