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Two different thermoplastic starches (TPS), namely maleic anhydride grafted starch (MA-g-starch) and epoxidized cardanol grafted starch (Epicard-g-starch), were successfully prepared by chemical modification without the addition of any plasticizer. The structure and properties were characterized by nuclear magnetic resonance (NMR), X-ray diffraction (XRD), hot press testing, scanning electron microscopy (SEM) and contact angle meter, respectively. Results from XRD showed that the highly crystalline structure of native starch was destroyed after modification. Continuous phase was obtained from both of the chemically modified starches after hot pressing at 130°C, indicating that they have good thermoplasticity. Subsequently, they were melt-blended with PLA. It was found that the Epicard-g-starch had a much finer dispersed phase size than MA-g-starch in PLA matrix due to its better hydrophobicity. As a result, the mechanical properties of PLA/Epicard-g-starch blend were superior to those of PLA/MA-g-starch blend., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Bio-sourced polymers, polylactide (PLA) and starch, have been melt-blended by lab-scale co-extruder with tung oil anhydride (TOA) as the plasticizer. The ready reaction between the maleic anhydride on TOA and the hydroxyl on starch led TOA molecules to accumulate on starch and increased the compatibility of PLA/starch blends, which was confirmed by FT-IR analyses and SEM. The TOA could change the mechanical properties and physical behaviors of PLA/starch blends. DSC and DMA analysis show that the TOA layer on starch has an effect on the thermal behavior of PLA in the ternary blend. The enrichment of TOA on starch improves the toughness and impact strength of the PLA/starch blends. The adding amount of TOA in PLA/starch blends primarily determined the compatibility and mechanical properties of the resulted ternary blends. The tensile and impact fracture modes of the PLA/starch blend with or without TOA has also been investigated by SEM analysis., (Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.)

Blends of entirely bio-sourced polymers, namely polylactide (PLA) and starch, have been melt-compounded by lab-scale co-extruder with castor oil (CO) as a plasticizer. The enrichment of castor oil on starch had great effect on the properties of the blends. If the castor oil was mainly dispersed in PLA matrix, the properties of the blends were poor, but when the hexamethylenediisocyanate (HDI) was grafted on starch granules the ready reactions between the hydroxyl on CO and the isocyante on the HDI-grafted starch (HGSTs) brought CO molecules enriched on starch particles. DSC analysis shows that the CO layer on starch has a positive effect on the crystallization of PLA in the ternary blend. The accumulation of CO on starch greatly improves the toughness and impact strength of PLA/starch blends. The grafting content of HDI on the starch granules primarily determined the compatibility and properties of the resulted blends., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Blends of entirely bio-sourced polymers, namely polylactide (PLA) and starch, have been melt-compounded by lab-scale co-extruder with epoxidized soybean oil (ESO) as a reactive compatibilizer. The starch granules were grafted with the maleic anhydride (MA) to enhance its reactivity with ESO. The ready reactions between the epoxy groups on ESO, the MA groups on MA-grafted starch (MGST) and the end carboxylic acid groups of PLA brought blending components together and formed a compatible compound. An elongation at break (EB) of 140% was obtained in the blend of PLA/MGST/ESO (80/10/10), increased from 5% of a pure PLA. The grafting content of the MA on the starch granules primarily determined the compatibility and properties of the ternary blends, which was also affected by the relative amount of MGST and ESO., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Objective: To explore the effect of the adipose derived stem cells (ADSCs) on the survival of random pattern skin flap in rabbits., Methods: ADSCs were isolated from fresh human fat and expanded in vitro for five passages. Then the characterization of ADSCs were determined by their CD marker profile and their ability to differentiate into osteogenic, adipogenic and chondrogenic lineages. On the back of the rabbits, two symmetric cephalic-based random pattern skin flaps were designed (6 cm x 2 cm). The right flaps were used as experimental groups with the contra-side flaps as control group. Human ADSCs were pre-labeled before seeding with fluorescent 3, 30-dioctadecyloxacarbocyanine perchlorate (DiO) dye. The experimental flaps evenly received 5-point injection of 2 x 10(6)Dio-labeled ADSCs resuspended in 0.5 ml of serum-free DMEM, while only 0.5 ml medium was injected into the control flaps. Seven days later, the survival rate of flaps was evaluated. The flaps underwent frozen section and were observed under the laser scanning confocal microscope to detect the fluorescence imaging. Flaps also underwent HE staining and were observed under light microscope to detect the vascular density., Results: Compared with control group, there was a significant increase of flap survival rate in the experimental group (P < 0.01). Histological analysis also demonstrated a statistically significant increase in capillary density in the experimental group., Conclusions: It suggests that ADSCs have a better immune compatibility and potential for enhancing the blood supply of random pattern skin flaps.

Zinc finger proteins have been implicated as transcription factors in the differentiation and development of cells and tissues in higher organisms. The classical C2H2 zinc finger motif is one main type of motif of zinc finger proteins. Our previous studies have shown that Zfp637, which comprises six consecutively typical and one atypical C2H2 zinc finger motifs, is highly expressed in undifferentiated or poorly differentiated cell lines, but is moderately or slightly expressed in normal tissues. We have also demonstrated that Zfp637 can promote cell proliferation. However, its role in the regulation of cell differentiation remains unknown. We report here that endogenous Zfp637 as well as mTERT is expressed in proliferating C2C12 myoblasts and that their expression is downregulated during myogenic differentiation. Constitutive expression of Zfp637 in C2C12 myoblasts increased mTERT expression and telomerase activity, and promoted the progression of the cell cycle and cell proliferation. By contrast, endogenous repression of Zfp637 expression by RNA interference downregulated the mTERT gene and the activity of telomerase, and markedly reduced cell proliferation. Overexpression of Zfp637 also inhibited the expression of myogenic differentiation-specific genes such as MyoD and myogenin, and prevented C2C12 myoblast differentiation. Our results suggest that Zfp637 inhibits muscle differentiation through a defect in the cell cycle exit by potentially regulating mTERT expression in C2C12 myoblasts. This may provide a new research line for studying muscle differentiation., ((c) 2010 Wiley-Liss, Inc.)

Dendritic cells (DCs) are important cells in initiating an immune response. A generation of functional DCs has potential clinical use in treating cancer. However, the source of DCs and patient immunodeficiency with cancer have been hindrances in clinical therapy. We generated DCs from human umbilical cord blood mononuclear cells (UBMCs) with recombinant human granulocyte-macrophage colony stimulating factor, recombinant human interleukin-4, and recombinant human tumor necrosis factor-alpha. The mature DC-A549 lung cancer vaccine (AgL-DC) was prepared through loading A549 lysate, treating with lipopolysaccharide (LPS) and positive selecting with CD83 magnetic beads. AgL-DC can secrete interleukin (IL)-12 and IL-1. Further in vitro analysis showed that AgL-DC notably induced human UBMC lymphocyte proliferation (p < 0.01) by 3-(4,5-dimethylthiazol-z-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, increased the cytotoxic T-lymphocyte (CTL) activity of UBMC lymphocytes against A549 cells (p < 0.05, at effector cells:target cells ratios of 50:1 and 100:1) by lactate dehydrogenase (LDH) cytotoxic assay, and improved production of IL-6 and tumor necrosis factor-beta (p < 0.01, p < 0.05) by enzyme-linked immunosorbent assay. Subsequently, the reconstitute immunity model in severe combined immunodeficiencies (SCID) mice has been established using human UBMC transplantation, and similar trends to results of UBMC in vitro experiments have been shown in lymphocyte proliferation, CTL activity, and IL-6 and tumor necrosis factor-beta secretion levels in these models. AgL-DC also significantly (p < 0.01) increased the antitumor effect in vivo. The tumor infiltrating immunocytes were positively expressed human CD83 and CD3 molecules, and they were negatively expressed in tumor tissue treated with control. These results have demonstrated that umbilical cord DCs are a useful source of vaccine cells for augmenting CTL-mediated cytotoxicity and have potential usefulness in cellular therapy for human cancer in a new vaccination strategy.

Objective: To establish the eukaryotic expression plasmid containing the code gene of Na+, K+-ATPase beta1-subunit (ATP1B1) and the basis of ATP1B1 applied to antitumor gene therapy., Methods: The ATP1B1 cDNA was amplified from leukocyte gene library and then cloned into the eukaryotic expression vector pEGFP-C3. The recombinant plasmid, named as pEGFP-ATP1B1, was determined with restriction enzyme and sequencing analyses. Next pEGFP-ATP1B1 was transferred into gastric adenocarcinoma SGC-7901 cells by lipofectamine, then ATP1B1 mRNA expression in transfected cells was detected by real-time PCR, and also ATPase was detected after cell transfection, as well as the proliferation of such cells was measured by MTT., Results: The analysis confirmed that the recombinant pEGFP-ATP1B1 contained the ATP1B1 cDNA. After cell transfection, the expression of ATP1B1 mRNA(129.2%) and the activity of ATPase [(2.95+/-0.210)%] were higher, and the growth of the SGC-7901 cells transfected with ATP1B1 was inhibited obviously when compared with the control group., Conclusion: The recombinant pEGFP-ATP1B1 is constructed successfully, and this recombinant eukaryotic expression vector could be used in additional studies on the biological effect of ATP1B1 and its use in anti-tumor gene therapy.

Objective: To detect the relation between the member LIGHT of TNF superfamily and the suppressor of cytokine signaling 3 (SOCS3), and to investigate the effect of SOCS3 on dendritic cell (DC) maturation induced by LIGHT., Methods: Bone marrow-derived DC (BMDC) was generated from mouse bone marrow monocyte by culturing with rmGM-CSF, rmIL-4 in vitro. SOCS3 mRNA in BMDC was analyzed by RT-PCR, and the protein of SOCS3 was measured by Western blot. After blocking the SOCS3 expression with the specific anti-sense oligonucleotide, we applied the flow cytometry to measure the expression of CD86 and CD40 on DC for making clear whether the silence of SOCS3 would regulate the LIGHT-stimulated DC maturation., Results: With the effect of LIGHT, the level of SOCS3 mRNA and protein in BMDC sharply increased. The specific antisense oligonucleotide could effectively block SOCS3 mRNA expressing in BMDC with the ratio of 49% and block SOCS3 protein expression with the ratio of 45%. Compared with SOCS3-unblocked DC, the SOCS3-blocked BMDC with stimulation of LIGHT showed higher CD40 and CD86 (P < 0.05)., Conclusion: LIGHT enhances the expression of SOCS3 during stimulating BMDC maturation. As more sensitive to LIGHT, the SOCS3-blocked BMDC is driven to more mature. SOCS3 presents a negative regulation mechanism in BMDC maturation induced

Objective: To investigate the growth inhibition and multidrug resistance (MDR) reversing effect of tanshinone I A on human breast cancer cells with estrogen receptor (ER) negative, and to elucidate its mechanism of activity., Methods: Human ER negative breast cancer cells (MDA-MB-231) were tested in vitro for cytotoxicity and colony formation inhibition. Brdu incorporation and cell cycle distribution were also checked through flow cytometry (FCM). With RT-PCR, the expressions of ADP-ribosyltransferase CNAD+; poly (ADP-ribose) polymerase)-like 1 (ADPRTL1), cytochrome P450 subfamily I (CYP1A1) and breast cancer resistance protein (BCRP/ABCG2) mRNA were detected for testing the response to tanshinone 1 A treatment., Results: After tanshinone I A treatment, the proliferation, colony formation and Brdu labeling indices of cancer cells decreased (P<0. 05). By FCM analysis, the increase of subG, and G0/G1 phase cell populations and decrease of S and G2/M phase cells were observed (P