High n-type and p-type conductivities and power factors achieved in a single conjugated polymer.

The charge transport properties of conjugated polymers are commonly limited by the energetic disorder. Recently, several amorphous conjugated polymers with planar backbone conformations and low energetic disorder have been investigated for applications in field-effect transistors and thermoelectrics. However, there is a lack of strategy to finely tune the interchain π-π contacts of these polymers that severely restricts the energetic disorder of interchain charge transport. Here, we demonstrate that it is feasible to achieve excellent conductivity and thermoelectric performance in polymers based on thiophene-fused benzodifurandione oligo(p-phenylenevinylene) through reducing the crystallization rate of side chains and, in this way, carefully controlling the degree of interchain π-π contacts. N-type (p-type) conductivities of more than 100 S cm-1 (400 S cm-1) and power factors of more than 200 µW m-1 K-2 (100 µW m-1 K-2) were achieved within a single polymer doped by different dopants. It further demonstrated the state-of-the-art power output of the first flexible single-polymer thermoelectric generator.

Chemical composition of Cyclocarya paliurus polysaccharide and inflammatory effects in lipopolysaccharide-stimulated RAW264.7 macrophage.

This study was designed to study the chemical composition of Cyclocarya paliurus polysaccharide and inflammatory effects in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage. A new elution (0.3% NaCl aqueous solution) of Cyclocarya paliurus polysaccharide (CPP-3) was characterized by different methods such as fourier transform infrared spectra (FT-IR), UV-vis, gas chromatography-mass spectrometry (GC-MS), high performance gel chromatography (HPGLC) and scanning electron microscopy (SEM). Cell viability was measured by MTT test, phagocytosis assay was measured by Neutral red uptake assay, nitrite was measured by Griess assay, TNF-α and IL-1ß analysis were measured by ELISA, PGE2 was measured by enzyme immunoassay system. The results showed that CPP-3 was comprised of two polysaccharides with average molecular weight (Mw) of 5.69×104Da and 4.94×103Da. CPP-3 contains six monosaccharides, of which are rhamnose (Rha), arabinose (Ara), xylose (Xyl), mannose (Man), glucose (Glu), galactose (Gal), the molar ratio of six monosaccharides is 0.060:0.109:0.053:0.128:0.293:0.357. CPP-3 increased the amount of NO released from mouse macrophage RAW264.7 and significantly increased the levels of TNF-α, IL-1ß and PGE2 (P<0.01). CPP-3 suppressed LPS-stimulated RAW264.7 macrophage to release NO, TNF-α, IL-1ß and PGE2 (P<0.01). CPP-3 and LPS accounted for synergistic effect on the release of NO and TNF-α, CPP-3 and LPS accounted for antagonistic effect on the release of IL-1ß and PGE2.

Polymer Membranes with Vertically Oriented Pores Constructed by 2D Freezing at Ambient Temperature.

Polymer membranes with well-controlled and vertically oriented pores are of great importance in the applications for water treatment and tissue engineering. On the basis of two-dimensional solvent freezing, we report environmentally friendly facile fabrication of such membranes from a broad spectrum of polymer resources including poly(vinylidene fluoride), poly(l-lactic acid), polyacrylonitrile, polystyrene, polysulfone and polypropylene. Dimethyl sulfone, diphenyl sulfone, and arachidic acid are selected as green solvents crystallized in the polymer matrices under two-dimensional temperature gradients induced by water at ambient temperature. Parallel Monte Carlo simulations of the lattice polymers demonstrate that the directional process is feasible for each polymer holding suitable interaction with a corresponding solvent. As a typical example of this approach, poly(vinylidene fluoride) membranes exhibit excellent tensile strength, high optical transparence, and outstanding separation performance for the mixtures of yeasts and lactobacilli.

The role of serum albumin in the metabolism of Boc5: molecular identification, species differences and contribution to plasma metabolism.

Boc5, the first nonpeptidic agonist of Glucagon-like peptide-1 receptor, has been recognized as a potential candidate for treatment of diabetes. However, the metabolic behaviors of this novel molecule in both human and experimental animals remain unclear. This study aimed to explore the metabolic behaviors of Boc5 in biological preparations from human, pig and rat. Boc5 was found to be very stable in liver microsomes of human, pig and rat, but it can be degraded to two metabolites in plasma from all three species, via the successive hydrolysis of the C-22 esters. Chemical inhibition studies using selective esterase inhibitors and assays with purified enzymes suggested that Boc5 hydrolysis in human was totally mediated by human serum albumin (HSA) rather than esterases. ESI-TOF-MS/MS analysis revealed that Lys525 of HSA could be modified by treatment with Boc5, strongly suggesting the pseudo-esterase activity of albumin. Studies on species differences in this albumin-mediated metabolism showed large species differences in degradation rate of Boc5, the half lives of Boc5 in plasma from three various species varied from 23.5 h to 83.1h, but they were much closer to the half lives of Boc5 in corresponding serum albumins, implying the predominant role of serum albumin in plasma metabolism of Boc5. Additionally, the effects of various ligands including fatty acids and several drugs with unambiguous binding sites on HSA, on the pseudo-esterase activity of HSA, were also investigated using both experimental and molecular modelling studies. These results showed that the binding of various ligands to HSA could significantly affect the pseudo-esterase activity of HSA towards Boc5, due to the ligand-induced conformation changes of HSA.

[Effect of bone marrow mesenchymal stem cells on acute graft versus host disease and graft versus leukemia after allogeneic bone marrow transplantation].

To investigate the effect of bone marrow mesenchymal stem cells (BMMSC) on acute graft versus host disease (aGVHD) and graft versus leukemia (GVL) after allogeneic bone marrow transplantation (allo-BMT), both bone marrow cells and BMMSC obtained after three to four weeks of culture from donor mice were transplanted into the recipient mice injected with acute lymphocytic leukemia cells 5 days before, the control group was injected with bone marrow cells alone. The survial time after allo-BMT was recorded; the general manifestation and pathological changes of aGVHD in recipient mice were observed; the effects of BMMSC on the quatity of CD4(+) and CD8(+) T cell in vivo after allo-BMT were evaluated by flow cytometry; chimerism was detected by sex chromosome. The results showed BMMSC could increase obviously the survival time, and delay onset of aGVHD, BMMSC could decrease the amount of CD4(+) T cell and increase CD8(+) T cell in vivo. It is concluded that cotransplantation of bone marrow cells with BMMSC from the same donor mice has GVL effect. BMMSC can alleviate aGVHD and maintain GVL effect after allo-BMT.