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For a long time, discoloring PET/cotton blend fabric is a difficult topic in textile industry. For it, this search work was carried out to stripping PET/cotton fabric dyed by disperse/direct dye with dimethyl formamide. Though experiment, results is discovered as follows: firstly, the PET/cotton fabric dyed by disperse/direct dye is swelled in the home-made swelling liquid. Then, put it into striping liquid which is mainly contain dimethyl formamide, and heat to 140°C，and keep 30 minutes. The stripping rate of three kinds of test samples can be over 80 percent, and some can reach 95 percent. While the strength retention rate also can reach about 90 Percent.

Cellulose fibers were chemically modified on surface by acrylamide polymerization and glutaraldehyde crosslinking. The chemical and morphological structures of modified cellulose fibers were investigated with X-ray diffraction, FTIR spectra, and scanning electron microscopy (SEM). The crystalline conformations of the cellulose fibers were slightly changed in polymerization and crosslinking process. The wet strength of modified cellulose fibers was improved. Appreciable difference between the surfaces of native and modified cellulose fibers was observed from SEM images.

Carbon microspheres (CMSs) were used as the carrier to prepare the Ag-loading CMSs (Ag/CMSs) antibacterial agent through the method of chemical adsorption. The morphologies and structures of modified CMSs were characterized by using the field emission Scanning Electron Microscope (SEM). The results showed that silver was absorbed on the surface of CMSs. The bacterial inhibition ring experiment showed that Ag/CMSs had good antibacterial activity against Staphylococcus aureus and Escherichia coli, meanwhile the diameters of the bacterial inhibition rings were 19 mm against Staphylococcus aureus and 21 mm against Escherichia coli, respectively.

With Ag-loading MWNTs antibacterial agent as functional material, the antibacterial functional PET fibers were prepared by melt blending spinning-draft one-step method. The crystallinity and the orientation of specimens were characterized by differential scanning calorimetry, polarization microscope and sound velocimeter. Moreover, the mechanical properties and antibacterial properties were measured. The results showed that the antibacterial PET fibers had good spinnability when the content of Ag-loading MWNTs less than 1.0 % (wt); compared with pure PET fibers, the degree of crystallinity, the degree of orientation and the fracture strength were improved, but the elongation was decreased; the antibacterial PET fibers exhibited excellent antibacterial properties against E.coli by the method of flask shaking.

Chitosan (CTS) and Ag-loading nano-SiO2 (SLS) are excellent antibacterial materials. However, when used alone, these monocomponent antibacterial agents are sometimes far from meeting requirements in special conditions. In this study, crosslinked chitosan-coated Ag-loading nano-SiO2 composites (CCTS-SLS) were synthesized by adsorption crosslinking reaction. Then Escherichia coil (ATCC 8099) was taken as the experimental bacteria for antibacterial tests. The experimental results indicate that the mass ratio of SLS to chitosan had the greatest influences on the value of MIC (minimal inhibitory concentration) for CCTS-SLS composite. However, the heating temperature had a weak influence on the antibacterial performance of CCTS-SLS composite.

Using the capillary rheometer to study the effect of shear rate, shear stress and temperature of Japanese and domestic PPS resin( fiber grade) on the apparent viscosity, index of non-Newtonian and viscous flow activation energy.The results show that with the increase of shear rate and temperature,compared to the domestic sample, Japanese sample has higher apparent viscosity, smaller non-Newtonian index(n),lower viscous flow activation energy,and smaller sensitivity to temperature.The Japanese specimens are suitable for processing and forming under high shear rate and spinning speed, but the domestic specimens are suitable for processing and froming under low shear rate and spinning speed.

Limited studies exist related to the siro-spun spinning of flax ( Linum usitatissimum L.) and cotton (Gossypium hirsutum) blends. The purpose of this study was to determine the influence of various siro-spun processing parameters, including twist factor, space between two rovings and specification of traveler, on yarn qualities, such as yarn hairiness, tenacity and evenness. Results show that both specification of traveler and space between two rovings significantly influenced yarn hairiness and evenness, and heavier traveler and greater space led to decreased hairiness, but bad evenness. Twist factor influenced yarn evenness highly significantly, and smaller twist factor led to worse yarn evenness. Results also indicate the optimum levels of siro-spun process parameters as follows: twist factor αm = 150, space between two rovings 8 mm, traveler Fo 5/0. In relation to the general ring-spinning yarn, the siro-spun spinning yarns had decreased hairiness, little increased tenacity and similar evenness.

The MWNTs-OH/PET composite fibers were prepared by the masterbatch melt blending spinning drawing one-step process (FDY), and the structure and properties of different contents of MWNTs-OH of the PET FDY fiber were studied. The results showed that the interaction between MWNTs-OH and PET matrix was enhanced after the modification of terephthalic acid (TPA), resulting in the improved interface compatibility. Also, the crystallinity of the composite fibers was raised 7% after the addition of modified MWNTs-OH. The fracture strength of composite fibers had firstly increased and then decreased with increasing of the content of MWNTs-OH, the strength of the composite fiber was largely improved by 60.5% with 0.2% (wt) of TPA/MWNTs-OH.

Wool fiber was firstly pretreated by nano-SiO2/Ag antibacterial agent, and then dyed with an acid dyes at low temperature by ultrasonic dyeing. Many factors had an important influence on the dye ability and the antibacterial behavior during the dyeing process of antibacterial wool fiber. The experimental results indicate that the dye-takeup rates of antibacterial wool fiber were enhanced with the increase of the concentration of nano-SiO2/Ag, the dyeing temperature, the dyeing time and the ultrasonic frequency (less than 60Hz). However, the antibacterial ratios of wool fiber were declined in the impact of these factors other than the concentration of antibacterial agent.

Multiwall carbon nanotubes (MWNTs) were modified by grafting the maleic anhydride (MAH). The morphologies and structures of modified multiwall carbon nanotubes (MWNTs) were characterized by using Scanning Electrohic Microscope (SEM) and Fourier Transformation Infrared (FTIR). The results showed that a layer of maleic anhydride was grafted on the surface of MWNTs by covalent bonding.

The antibacterial PET (polyethylene terephthalate) masterbatch was extruded from twin screw extruder, using silver and zinc-loading Nano-SiO2 antibacterial agent (SLSZ) as the functional material. The content of SLSZ and extruding techniques were investigated. The dispersion and compatibility of antibacterial agent in antibacterial PET masterbatch were further characterized using Scanning Electron Microscopy and Transmission Electron Microscopy. The antibacterial performances and adsorption process of the antibacterial PET masterbatch against Escherichia coli (E. coli) were tested using alive-bacteria-counting method. The experimental results indicate that when the content of SLSZ was 30 wt. %, the antibacterial agent with an average diameter of 150nm showed excellent dispersion and compatibility in antibacterial PET masterbatch, and had excellent antibacterial performances. The adsorption process of antibacterial PET masterbatch against E. coli was controlled by Coulomb force between them. As the amount of the antibacterial PET masterbatch increased, the adsorbing rate and capacity were increased.

Ionizing radiation can induce DNA damage and cell death by generating reactive oxygen species (ROS). The objective of this study was to investigate the radioprotective effect of paeoniflorin (PF, a main bioactive component in the traditional Chinese herb peony) on irradiated thymocytes and discover the possible mechanisms of protection. We found 60Co gamma-ray irradiation increased cell death and DNA fragmentation in a dose-dependent manner while increasing intracellular ROS. Pretreatment of thymocytes with PF (50-200 microg/ml) reversed this tendency and attenuated irradiation-induced ROS generation. Hydroxyl-scavenging action of PF in vitro was detected through electron spin resonance assay. Several anti-apoptotic characteristics of PF, including the ability to diminish cytosolic Ca2+ concentration, inhibit caspase-3 activation, and upregulate Bcl-2 and downregulate Bax in 4Gy-irradiated thymocytes were determined. Extracellular regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38 kinase were activated by 4Gy irradiation, whereas its activations were partly blocked by pretreatment of cells with PF. The presence of ERK inhibitor PD98059, JNK inhibitor SP600125 and p38 inhibitor SB203580 decreased cell death in 4Gy-irradiated thymocytes. These results suggest PF protects thymocytes against irradiation-induced cell damage by scavenging ROS and attenuating the activation of the mitogen-activated protein kinases.

To identify differentially expressed genes in mouse bone marrow involved in radiation-induced injury.Microarray analysis was used to identify the differentially expressed genes and other techniques, e.g., polymerase chain reaction (PCR), western-blotting and antisense were also used to validate the results.DNA microarray analysis demonstrated that the mRNA of 34 genes increased and 69 genes decreased in mouse bone marrow cells (BMC) from C57BL mice 6 h after a whole body dose of 6.5 Gy. These differentially expressed genes were involved in a number of processes including DNA replication/repair, proliferation/apoptosis, cell cycle control and RNA processing. In these experiments, a decline of the mammalian homolog Sir2a (an acronym for the silent mating type information regulation 2 homolog [SIRT1]) mRNA accompanied by an increase of P53 protein acetylation was observed in irradiated BMC. To determine whether the reduced SIRT1 is related to the higher acetylation status of P53 after irradiation, we designed and synthesized antisense oligonucleotides (AS) targeting human SIRT1 mRNA. Notably, AS transfection increased tumor protein 53 (P53) protein acetylation and bax-luciferase activity in human bone marrow stromal cell line (HS-5) after radiation. Furthermore, the AS transfer stimulated cell apoptosis in post-irradiation HS-5 cells.Ionizing radiation (IR) affects the expression of a series of genes including genes involved in G1/S transition and the P53 pathway. Among those, reduction of SIRT1 was seen to be involved in transactivation of P53.

Aim: To investigate the effect of antisense oligodeoxynucleotides (ASODN) targeting Pim-2 on cell proliferation of DU-145 cells. Methods: Three ASODN targeting Pim-2 were designed and synthesized. After transfection with ASODN, cell proliferation was analyzed using an MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3- carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H -tetrazolium, inner salt] assay. In addition, Pim-2 mRNA, protein levels, and cell cycles were examined. Results: The ASODN designed and synthesized by our laboratory significantly reduced Pim-2 mRNA level and protein content in DU-145 cells. After transfection with ASODN for 48 h, a marked reduction in cell viability was observed in DU-145 cells in a dose-dependent manner. No remarkable apoptosis occurred in cells treated with ASODN compared with control cells. However, it should be noted that G 1 phase arrest was clearly observed in ASODN-treated cells. Conclusion: ASODN targeting Pim-2 resulted in a marked reduction in DU-145 cell proliferation, and induction of G 1 phase cell cycle arrest is one of the important mechanisms for ASODN to reduce cell growth. Moreover, antisense inhibition of Pim-2 expression provides a new promising therapy target for prostate cancer.

PET fiber was preprocessed by means of microwave radiation. Different reaction parameters such as the time, the power and the Ph value of solution were optioned to study the degree of the fiber hydrolysis. The changes of mechanical performance and hygroscopicity of the fiber were analyzed, which showed that the best power of microwave radiation was the 250W, the best reaction time was 5 min, and the Ph value of solution was 9. Compared with the untreated fiber, the fracture strength of treated fiber is 1.686cN/dtex and the moisture regain is 0.58%. The morphology structure were characterized by SEM and the fracture strength were tested by filament electronic strength tester. The results showed that the surface of PET fibers became rough and the quantities of the -OH and -COOH functional groups on the surface increased after etching. Meanwhile the hygroscopicity of the treated fibers had been enhanced obviously and the fiber strength had been reduced.

Survivin, an inhibitor of apoptosis protein, deserves attention as a selective target for cancer therapy because it is overexpressed in many cancers, including human hepatocellular carcinoma (HCC). Here, we report a novel antisense oligonucleotide (ASO) against survivin for its effectiveness against tumor growth both in vitro and in vivo, and providing evidence in treatment for HCC. Initially, transfection of liver tumor cells HepG2 with ASO resulted in significant cells growth inhibition and reduction expression of survivin mRNA and protein, in a dose-dependent manner. Using caspase-3 protease activation assays, we observed that ASO has induced significantly greater apoptosis rate compared to control oligonucleotides. Furthermore, we used an orthotopic transplant model of HCC in nude mice to investigate the effect of ASO on tumor growth in vivo, and ASO reagents were delivered by intravenous injection. Interestingly, this systemic treatment also resulted in significant inhibition in tumor growth. Tumor growth in mice treated with ASO (50 and 75 mg/kg per day) was significantly inhibited (45.31% and 60.94%, respectively) compared with saline-injected group (p0.01), in a dose-dependent manner, and the effect of ASO on tumor growth was associated with downregulation of survivin in tumor xenografts. Moreover, the level of serum alpha-fetoprotein in ASO-treated groups was also decreased in a dose-dependent manner. Taken together, these data suggest that the usefulness of survivin ASO could potentially be a promising gene therapy approach to treatment of HCC.

The tumor suppressor p53-related p73 shares significant amino-acid sequence identity with p53. Like p53, p73 recognizes canonical p53 DNA-binding sites and activates p53-responsive target genes and induces apoptosis. Moreover, SIRT1 binds to p53 while repressing the expression of their target genes. Here, we report that SIRT1 also binds to p73 and suppresses p73-dependent transcriptional activity. SIRT1 in human cells reduces the transcriptional activity of p73, and partly inhibits apoptosis induced by p73. Furthermore, SIRT1 can deacetylate p73 protein acetylation both in vivo and in vitro. Collectively, these data suggest that SIRT1 can modulate p73 activity via deacetylation.