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Forward osmosis (FO) as an energy-saving membrane process has attracted much attention in food concentration, water treatment, and desalination. Thin film composite (TFC) membrane is the most popular FO membrane, but it suffers from the internal concentration polarization (ICP), which significantly limits the water flux and FO efficiency. In this report, we demonstrate a novel and high-performing thin film nanocomposite (TFN) membrane that employs a hydrophilic interlayer composed of imogolite nanotubes (INTs) and polydopamine (PDA). The INTs can be adhered to the porous substrate by the self-polymerization of PDA, and the as-prepared PDA/INTs interlayer displays a nanostructured network with outstanding hydrophilicity. The detailed investigation was conducted to understand the relationship between the structure and property of the PDA/INTs interlayer and the morphology and performance of the TFN membrane. The TFN membrane with the PDA/INTs interlayer performs a thinner and smoother polyamide selective layer. Correspondingly, the TFN membrane shows a water flux of 18.38 L·m−2·h−1, which is 2.18 times of the pristine TFC membrane. Moreover, the TFN membrane has a minimized structural parameter (577 µm), almost a half of that of the pristine one (949 ·m). It reveals that the ICP effect of TFC membrane can be effectively alleviated by using a hydrophilic PDA/INTs interlayer. This TFN membrane with a satisfactory water permeability is promising in terms of future applications. [ABSTRACT FROM AUTHOR]

Purpose: FLT3 mutations occurred in approximately one third of patients with acute myeloid leukemia (AML). FLT3-ITD mutations caused the constitutive activation of the RAS/MAPK signaling pathway. Ribosomal S6 Kinases (RSKs) were serine/threonine kinases that function downstream of the Ras/Raf/MEK/ERK signaling pathway. However, roles and mechanisms of RSKs inhibitor LJH-685, and combinational effects of LJH-685 and FLT3 inhibitor FF-10101 on AML cells were till unclear. Methods: Cell viability assay, CFSE assay, RT-qPCR, Colony formation assay, PI stain, Annexin-V/7-AAD double stain, Western blot, and Xenogeneic transplantation methods were used to used to investigate roles and mechanisms of LJH-685 in the leukemogenesis of AML. Results: LJH-685 inhibited the proliferation and clone formation of AML cells, caused cell cycle arrest and induced the apoptosis of AML cells via inhibiting the RSK-YB-1 signaling pathway. MV4-11 and MOLM-13 cells carrying FLT3-ITD mutations were more sensitive to LJH-685 than that of other AML cell lines. Further studies suggested that LJH-685 combined with Daunorubicin or FF- 10101 synergistically inhibited the cell viability, promoted the apoptosis and caused cycle arrest of AML cells carrying FLT3-ITD mutations. Moreover, in vivo experiments also indicated that LJH-685 combined with FF-10101 or Daunorubicin prolonged the survival time of NSG mice and reduced the leukemogenesis of AML. Conclusion: Thus, these observations demonstrated combination of RSK inhibitor LJH-685 and FLT3 inhibitor FF-10101 showed synergism anti-leukemia effects in AML cell lines with FLT3-ITD mutations via inhibiting MAPK-RSKs-YB-1 pathway and provided new targets for therapeutic intervention especially for AML with FLT3-ITD mutations and Daunorubicin-resistant AML. [ABSTRACT FROM AUTHOR]

Layer-by-layer (LbL) assembly technology is a facile method for constructing thin film composite membrane. Herein, a novel nanofiltration (NF) membrane was prepared by LbL assembly of polyethyleneimine (PEI) and sodium lignosulfonate (LS) followed by cross-linking. The surface composition, morphology, and property of PEI/LS bilayer were detailedly investigated by FTIR/ATR, XPS, SEM, AFM, and water contact angle test. The PEI/LS bilayer full of amino and hydroxyl groups presents increased roughness and improved hydrophilicity. Moreover, the NF performance of PEI/LS LbL assembly membranes can be modulated by bilayer number, polyelectrolyte concentration, and salt content. The water flux reduced while the salt rejection greatly improved as increasing the bilayer numbers, PEI concentration, or NaCI content. More than 95% MgSO4 and MgCI2, as well as 80% NaCI can be rejected by a NF membrane prepared by 6 PEI/LS bilayers, 1 wt% PEI, 0.5 wt% LS, and 1 mol/L NaCI. Furthermore, this NF membrane can be used to remove more than 95% heavy metal ions (Cd2+, Zn2+, Mn2+, Cr2+, Cu2+, and Ni2+). This work proposed a promising NF membrane by using PEI/LS as low cost polyelectrolytes and facile LbL assembly method, which should receive much attention in water purification. [ABSTRACT FROM AUTHOR]

Cellulose triacetate (CTA) porous membranes were firstly prepared by the combined nonsolvent-thermally induced phase separation (N-TIPS) method. Dimethyl sulfone (DMSO2) and polyethylene glycol (PEG400) were respectively chosen as the TIPS solvent and additive of CTA, while water was used as the NIPS nonsolvent. Their Hansen solubility parameters were analyzed to understand the solution thermodynamics. Detailed investigation was applied on the effects of the polymer concentration, the coagulation bath temperature and the coagulation bath composition on the CTA porous membranes. It is found that both NIPS and TIPS effects simultaneously exist and compete with each other, and further affect the membrane morphology and performance. The NIPS effect can be promoted by lowering the CTA concentration or elevating the coagulation bath temperature, resulting in figure-like macropores and porous top surface. The obtained CTA porous membranes show a water flux as high as 2002.9 ± 55.2 L/m2h. On the contrary, the TIPS effect becomes the dominant factor, and leads to the symmetric sponge-like pores, which facilitate to enhance the mechanical properties. Besides, CTA porous membranes present large surface pore size as well as low fraction of figure-like macropores as increasing the DMSO2 content in the coagulation bath. These CTA porous membranes with excellent water permeability and mechanical strength are promising candidates for microfiltration or the porous substrates of thin film composite membranes. [ABSTRACT FROM AUTHOR]

In this work, a series of high performance bio-based polyurethanes (bio-PUs) were synthesized from polylactide (PLA)-based diols, different diisocyanates (TDI, MDI, HDI, IPDI) and chain extender 1,4-butanediol, in which different soft and hard segments are used to adjust their transition temperatures and mechanical properties. Poly(lactide- co-caprolactone) copolymer diols ( co-PLAols) instead of PLA diols as the soft segment improved the thermal stability and mechanical properties of the synthesized bio-PUs. Among them, MDI-based bio-PUs have the highest T (43.8 °C), tensile strength (23.5 MPa) and modulus (380.8 MPa), while HDI-based bio-PUs have the lowest T (21.4 °C) and highest elongation at break (580%). Especially, the bio-PUs synthesized from co-PLAols and MDI demonstrate better mechanical properties, closed to petroleum-based commodities. Furthermore, the obtained bio-PUs display good shape memory properties at body temperature and cytocompatibility. Therefore, these bio-PUs are promising for applications in biomedical fields. [ABSTRACT FROM AUTHOR]

Porous carbon membranes were favorably fabricated through the pyrolysis of polyacrylonitrile (PAN) precursors, which were prepared with a template-free technique-thermally induced phase separation. These carbon membranes possess hierarchical pores, including cellular macropores across the whole membranes and much small pores in the matrix as well as on the pore walls. Nitrogen adsorption indicates micropores (1.47 and 1.84 nm) and mesopores (2.21 nm) exist inside the carbon membranes, resulting in their specific surface area as large as 1062 m/g. The carbon membranes were used to adsorb organic dyes (methyl orange, Congo red, and rhodamine B) from aqueous solutions based on their advantages of hierarchical pore structures and large specific surface area. It is particularly noteworthy that the membranes present a selective adsorption towards methyl orange, whose molecular size (1.2 nm) is smaller than those of Congo red (2.3 nm) and rhodamine B (1.8 nm). This attractive result can be attributed to the steric structure matching between the molecular size and the pore size, rather than electrostatic attraction. Furthermore, the used carbon membranes can be easily regenerated by hydrochloric acid, and their recovery adsorption ratio maintains above 90% even in the third cycle. This work may provide a new route for carbon-based adsorbents with hierarchical pores via a template-free approach, which could be promisingly applied to selectively remove dye contaminants in aqueous effluents. [ABSTRACT FROM AUTHOR]

Antithymocyte globulin (ATG) combined with cyclosporine A (CsA) has been widely used as a standard regimen in the treatment of aplastic anemia (AA), especially in severe aplastic anemia (SAA). Abnormally activated T cells might be the immune pathogenesis of AA. T cell immune response cDNA 7 (TIRC7) has been demonstrated its essential role in T cell activation; however, little is known about the role of TIRC7 in AA. In this study, we documented that TIRC7 levels in CsA group were higher than that in ATG + CsA (AC) group only in the follow-up phase ( P < 0.05; P < 0.05); nevertheless, TIRC7 levels in SAA group were elevated than non severe aplastic anemia group not only in the treatment phase ( P < 0.05; P < 0.05) but also in the follow-up phase ( P < 0.05; P < 0.01). The trend of changes of T helper (Th) 1, Th17 and Th22 levels before and after treatment was similar to the changes of TIRC7 levels in either AC group or CsA group. Thus, TIRC7 might be involved in the pathogenesis of AA and AC might down-regulate Th1 cells by modulating the expression of TIRC7 in AA. [ABSTRACT FROM AUTHOR]

A carbon dioxide copolymer poly(urethane-amine) (PUA) was blended with poly(propylene carbonate) (PPC) in order to improve the toughness and flexibility of PPC without sacrificing other mechanical properties. Compared with pure PPC, the PPC/PUA blend with 5 wt% PUA loading showed a 400% increase in elongation at break, whilst the corresponding yielding strength remained as high as 33.5 MPa and Young's modulus showed slightly decrease. The intermolecular hydrogen bonding interaction in PPC/PUA blends was confirmed by FTIR, 2D IR and XPS spectra analysis, and finely dispersed particulate structure of PUA in PPC was observed in the SEM images, which provided good evidence for the toughening mechanism of PPC. [ABSTRACT FROM AUTHOR]

Acute graft-versus-host disease (aGVHD) has become the important complication post-allogeneic hematopoietic stem cell transplantation. Abnormally activated T cells might play an important role in the pathogenesis of aGVHD. But its exact mechanism remains poorly understood. T cell immune response cDNA 7 (TIRC7) has been identified to be essential in T cell activation; however, the role of TIRC7 in aGVHD remains unclear. The purpose of this study was to measure the expression of TIRC7 and T helper (Th) cells in patients with aGVHD before and after treatment. We showed that TIRC7 levels in aGVHD patients were higher than those of healthy controls and markedly declined after treatment. The levels of IFN-γ (Th1), IL-17 (Th17), and IL-22 (Th22) were in accordance with the grade of aGVHD. In addition, TIRC7 levels were also associated with the severity of aGVHD. In conclusion, TIRC7 might be involved in the pathogenesis of aGVHD and TIRC7 level might be an indicator to evaluate the response of patients with aGVHD to treatment. [ABSTRACT FROM AUTHOR]