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81.
Mesenchymal stem cells (MSCs), such as adipose-derived stem cells (ADSCs), have the most impressive ability to reduce inflammation through paracrine growth factors and cytokines that participate in inflammation. Tumor necrosis factor (TNF)-α bioactivity is a prerequisite in several inflammatory and autoimmune disease models. This study investigated the effects of TNF-α stimulate on ADSCs in the tumor microenvironment. The RNAseq analysis and cytokines assay demonstrated that TNF-α stimulated ADSCs proliferation and pro-inflammatory genes that correlated to leukocytes differentiation were upregulated. We found that upregulation of TLR2 or PTGS2 toward to IRF7 gene-associated with immunomodulatory and antitumor pathway under TNF-α treatment. In TNF-α-treated ADSCs cultured with the bladder cancer (BC) cell medium, the results showed that apoptosis ratio and OCT-4 and TLR2 genes which maintained the self-renewal ability of stem cells were decreased. Furthermore, the cell survival regulation genes including TRAF1, NF-kB, and IRF7 were upregulated in TNF-α-treated ADSCs. Additionally, these genes have not been upregulated in BC cell medium. A parallel study showed that tumor progressing genes were downregulated in TNF-α-treated ADSCs. Hence, the study suggests that TNF-α enhances the immunomodulatory potential of ADSCs during tumorigenesis and provides insight into highly efficacious MSC-based therapeutic options for BC.  相似文献   
82.
Abstract

This paper discusses the diffusion rendering of ink painting and focuses on synthesizing the effects of ink‐refusal and stroke‐trace‐reservation that make the ink paintings remarkable and implicitly beautiful. We derive the diffusion model, which can be used as an ink‐painting rendering approach, from the physical interaction between ink and paper. In this paper, we have successfully developed a method that is able to simulate the artistic effects of ink‐refusal and stroke‐trace‐reservation in ink paintings.  相似文献   
83.
Crabwise ZnO nanowires with an average length of 5 microm and an average diameter of 30 nm were selectively grown on ZnO:Ga/glass templates. Cathodoluminescence measurement indicated that the crystal quality of the crabwise ZnO nanowires was good. With an applied voltage of 120 V, the crabwise ZnO nanowire field emitters gave an emission current of 0.1 mA/cm2. Moreover, the field enhancement factor, beta, of the crabwise ZnO nanowires was approximately 980.  相似文献   
84.
Abstract

For industrial constrained manipulators, the interactive motion and force dynamics between the end effector and the constrained environment occur at both the normal space and the tangent space to the constraint manifold. In order to characterize such interactive behaviors, it is advantageous to develop a specific coordinate frame to facilitate the formulation of such constrained dynamics. Most previous approaches solved the problem from the algebraic viewpoint. This paper, on the other hand, develops a systematic method to construct a geometric constraint frame from the perspective of integral manifold theory. A constraint frame, distinct from previous orthogonal moving frames, behaves as a partially orthogonal coordinate system and is endowed with intrinsic geometric implications which are beneficial to the dynamic analysis and the controller design. The algebraic and geometric points of view concerning the constrained systems are compared and discussed. An illustrative example for constrained manipulators will be demonstrated.  相似文献   
85.
To improve the cytotoxicity of PEI25k and the transfection efficiency of poly(β-amino ester) with DNA, we synthesized a poly(β-amino ester), PEDP, bearing ester linkages in the backbone and tertiary amines in the backbone and side chain and prepared a binary mixture, PEDP–PEI25k, using physical blending meyhod. Both poly(β-amino ester) PEDP and binary mixture PEDP–PEI25k, readily self-assembled with plasmid DNA (pCMV-β gal) in a HEPES buffer, were characterized by dynamic light scattering. The results reveal that PEDP–PEI25k was able to self-assemble plasmid DNA into PEDP–PEI25k/DNA nano-complexes small enough to enter a cell through endocytosis. Titration studies were performed to determine the buffering capacities of PEDP and PEDP–PEI25k. The COS-7 cell viabilities in the presence of PEDP and PEDP–PEI25k were studied. At low mass ratio of PEDP/PEI25k (1/1), it is found that the transfection curve of PEDP–PEI25k/DNA bearing a maximum peak is similar to that of PEI25k/DNA. In addition, the PEDP–PEI25k/DNA complexes were able to transfect COS-7 cells in vitro with a high efficiency comparable to a well-known gene carrier PEI25k/DNA. The results indicate that binary mixture PEDP–PEI25k is an attractive cationic carrier for gene delivery and an interesting candidate for further study.  相似文献   
86.
Hydrogenated nanocrystalline silicon (nc-Si:H) films were prepared by a pulsed-DC magnetron sputtering method under an atmosphere of hydrogen/argon mixture. The effects of hydrogen concentration on the structural and electrical properties of the films were systematically investigated using grazing incidence X-ray diffraction (GIXRD), Raman spectroscopy, and conductivity measurement. A threshold hydrogen concentration of about 70% was found necessary before any crystallinity was detectable. The deposition rate decreased monotonically with increasing hydrogen concentration, while the conductivity varied with crystallite size. The abnormally low conductivity level of these nc-Si:H films was due to the extraordinarily high defect density, which was attributed both to the enhanced ion bombardment from the pulsed-DC plasma and to the oxygen contamination from the target.  相似文献   
87.
Suspension cells can provide a source of cells for cellular reprogramming, but they are difficult to transfect by nonviral vectors. An efficient and safe nonviral vector (GO‐Fe3O4‐PEI complexes) based on iron oxide nanoparticle (Fe3O4)‐decorated graphene oxide (GO) complexed with polyethylenimine (PEI) for the first time is developed for delivering three individual episomal plasmids (pCXLE‐hOCT3/4‐shp53, pCXLE‐hSK, and pCXLE‐hUL) encoding pluripotent‐related factors of Oct3/4, shRNA against p53, Sox2, Klf4, L‐Myc, and Lin28 into human peripheral blood mononuclear cells (PBMCs) simultaneously. The combined treatment of magnetic stirring and near‐infrared (NIR)‐laser irradiation, which can promote contact between the complexes and floating cells and increase the cell membrane permeability, respectively, is used to conduct multiple physical stimulations for suspension PBMCs transfection. The PCR analysis shows that the combinatorial effect of magnetic targeting and photothermal stimulation obviously promoted the transfection efficiency of suspension cells. The transfected cells show positive expression of the pluripotency markers, including Nanog, Oct4, and Sox2, and have potential to differentiate into mesoderm and ectoderm cells. The results demonstrate that the GO‐Fe3O4‐PEI complex provides a safe, convenient, and efficient tool for reprogramming PBMCs into partially induced pluripotent stem cells, which are able to rapidly transdifferentiate into mesodermal lineages without full reprogramming.  相似文献   
88.
The two crystal growth parameters most likely to affect the occurrence of GaAs0.5Sb0.5 spinodal decomposition during organometallic vapor phase epitaxial (OMVPE) growth, substrate temperature and substrate orientation, were investigated in detail. The temperature range studied was the widest over which good morphology layers could be grown, from 550 to 680° C. The InP substrate orientations used were (100), (221) and (311). The growth process was found to be diffusion controlled at high temperatures, but to be controlled by surface kinetics at temperatures below approximately 620° C, depending on substrate orientation. Growth of high quality layers was found to be much easier between 570 and 640° C. In addition, the 77 K PL intensity is much stronger for layers grown in this temperature range. The minimum PL halfwidth at 77 K is 20 meV and at 8 K is 16 meV. The typical room temperature hole mobilities are 100 cm2/Vs with hole concentrations of 2 x 1017 cm-3 in undoped material. The temperature dependence of mobility is consistent with enhanced alloy scattering. Surprisingly, the growth temperature has no significant effect on either PL halfwidth or hole mobility between 560 and 660° C. The single Raman line observed for the unannealed alloy is split after annealing into two lines corresponding to the GaAs-rich and GaSb-rich alloys on either side of the range of solid immiscibility. The spinodal decomposition apparently starts at the surface where the coherency strain, which stabilizes the single phase alloy, is smallest.  相似文献   
89.
J.S. Cherng  D.S. Chang 《Vacuum》2009,84(5):653-197
A series of studies on the pulsed-DC reactive sputtering of highly (002)-textured aluminum nitride (AlN) thin films was conducted with systematically adjusted pulse parameters including reverse voltage, pulse frequency, and pulse duration. The film quality was evaluated by the full width at half maximum (FWHM) of the (002) rocking curve as well as the (002) peak intensity. In the asymmetric bipolar mode, the FWHM increases while the peak intensity decreases with reverse voltage, implying a detrimental effect of reverse voltage on the quality of AlN film. Whereas in the unipolar mode, the film quality improves with pulse frequency as evidenced by the decreasing FWHM and increasing peak intensity. It is also found that there is a critical pulse duration of about 500 μs, beyond which the FWHM starts to increase while the peak intensity starts to decrease due to target poisoning. Typical measurements on thus-optimized AlN film show a roughness of 1.7 nm and a (002) FWHM of less than 1.9°.  相似文献   
90.
In current clinical practice the "double-stapling technique" is the standard for reanastomosis following minimally invasive sigmoid resection. In the present study, we compared the TESA technique (transient endoluminally stented anastomosis) with conventional stapled anastomosis and evaluated the effect of remnant foreign material on follow-up examination with endosonography. Laparoscopic sigmoid resection was performed in 12 pigs (mean weight 63+/-5.9 kg). Animals were randomly divided into two groups: In Group A, reanastomosis was performed following a standard technique using a 29-mm circular stapler. In Group B, the TESA technique using a resorbable radiopaque stent of polyglycolic acid was applied. The anastomosis was examined by plain x-ray on days 1, 7, and 14, and by contrast enema on day 42, respectively. Endosonography, macroscopic inspection, and histological evaluation of the anastomosis were performed on day 42. All anastomoses in group A were patent. In one animal in Group B stent displacement with subsequent leak of the anastomosis was observed. Circumferential length of the anastomosis on day 42 did not differ between the groups (Group A: 8.00+/-0.45 cm vs. Group B: 7.8+/-2.0 cm, p = 0.82). The duration of the operation was 130+/-27 minutes in Group A and 100+/-18 minutes in Group B (p = 0.06). Weight gain was equal: Group A: 24+/-9.6 kg vs. Group B: 24+/-5.0 kg, p = 0.74. Endosonography on day 42 postoperatively in the area of the anastomosis in group A was impaired due to metallic staples. TESA is a competitive method for reanastomosis following laparoscopic sigmoid resection. In contrast to the conventional technique, the anastomosis is free of foreign material 1 month after the operation, which facilitates follow-up examinations with endosonography as well as other imaging diagnostics.  相似文献   
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