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991.
Huang XX  Zhou CL  Wang H  Chen C  Yu SQ  Xu Q  Zhu YY  Ren Y 《AAPS PharmSciTech》2011,12(2):665-672
Hydroxypropyl-sulfobutyl-β-cyclodextrin (HP-SBE-β-CD) inclusion complex was developed and used as a drug delivery system for DTX (DTX/HP-SBE-β-CD). The objective of the present study was to evaluate and compare the biological properties of DTX/HP-SBE-Β-CD with Taxotere®. The pharmacokinetics, biodistribution, antitumor efficacy in vivo and in vitro, and safety evaluation of DTX/HP-SBE-β-CD were studied. The most significant finding was that it was possible to prepare a Polysorbate-80-free inclusion complex for DTX. Studies based on pharmacokinetics, biodistribution, and antitumor efficacy indicated that DTX/HP-SBE-β-CD had similar pharmacokinetic properties and antitumor efficacy both in vitro and in vivo as Taxotere®. Fortunately, this new drug delivery system attenuated the side effects when used in vivo. As a consequence, DTX/HP-SBE-β-CD may be a promising alternative to Taxotere® for cancer chemotherapy treatment with reduced side effects. The therapeutic potential against a variety of human tumors and low toxicity demonstrated in a stringent study clearly warrant clinical investigation of DTX/HP-SBE-β-CD for possible use against human tumors.Key words: antitumor efficacy, biodistribution, DTX/HP-SBE-β-CD, pharmacokinetics, safety evaluation  相似文献   
992.
A novel ternary complex, TbL5L′(ClO4)3·3H2O, two binary complexes, TbL7(ClO4)3·3H2O and TbL′3.5(ClO4)3·4H2O has been synthesized (using diphenyl sulphoxide as the first ligand L, bipyridine as the second ligand L′). Their composition was analysed by element analysis, coordination titration, IR spectra and 1H‐NMR, and the fluorescence emission mechanism, fluorescence intensities and phosphorescence spectra were also investigated by comparison. It was shown that the ternary rare‐earth complex showed stronger fluorescence intensities than the binary rare‐earth complexes in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 8.23 times, 3.58 times as strong as that of the binary systems TbL7(ClO4)3·3H2O and TbL′3.5 (ClO4)3·4H2O, respectively. By fluorescence analysis it was found that both diphenyl sulphoxide and bipyridine could sensitize the fluorescence intensities of rare‐earth ions. In particular, in the ternary rare‐earth complex, introduction of bipyridine was of benefit to the fluorescence properties of Tb(III). Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
993.
Peng XW  Ren JL  Zhong LX  Sun RC 《Biomacromolecules》2011,12(9):3321-3329
Interest in xylan-rich hemicelluloses (XH) film is growing, and efforts have been made to prepare XH films with improved mechanical properties. This work described an effective approach to produce nanocomposite films with enhanced mechanical properties by incorporation of cellulose nanofibers (CNFs) into XH. Aqueous dispersions of XH (64-75 wt %), sorbitol (16-25 wt %), and CNF (0-20 wt %) were cast at a temperature of 23 °C and 50% relative humidity. The surface morphology of the films was revealed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The thermal properties and crystal structure of the films were evaluated by thermal analysis (TG) and X-ray diffraction (XRD). The surface of XH films with and without CNF was composed primarily of nanonodules, and CNFs were embedded in the XH matrix. Freeze-dried XH powder was amorphous, whereas the films with and without CNF showed a distinct peak at around 2θ = 18°, which suggested that XH molecules aggregated or reordered in the casting solution or during water evaporation. Furthermore, the nanocomposite films had improved thermal stability. XH film with 25 wt % plasticizer (sorbitol, based on dry XH weight) showed poor mechanical properties, whereas incorporation of CNF (5-20 wt %, based on the total dry mixture) into the film resulted in enhanced mechanical properties due to the high aspect ratio and mechanical strength of CNF and strong interactions between CNF and XH matrix. This effective method makes it possible to produce hemicellulose-based biomaterials of high quality.  相似文献   
994.
We have recently shown that IgG1 directed against antigens thought to be involved in the pathogenesis of rheumatoid arthritis harbor different glycan moieties on their Fc-tail, as compared with total sera IgG1. Given the crucial roles of Fc-linked N-glycans for the structure and biological activity of IgG, Fc-glycosylation of antibodies is receiving considerable interest. However, so far little is known about the signals and factors that could influence the composition of these carbohydrate structures on secreted IgG produced by B lymphocytes. Here we show that both "environmental" factors, such as all-trans retinoic acid (a natural metabolite of vitamin A), as well as factors stimulating the innate immune system (i.e. CpG oligodeoxynucleotide, a ligand for toll-like receptor 9) or coming from the adaptive immune system (i.e. interleukin-21, a T-cell derived cytokine) can modulate IgG1 Fc-glycosylation. These factors affect Fc-glycan profiles in different ways. CpG oligodeoxynucleotide and interleukin-21 increase Fc-linked galactosylation and reduce bisecting N-acetylglucosamine levels, whereas all-trans retinoic acid significantly decreases galactosylation and sialylation levels. Moreover, these effects appeared to be stable and specific for secreted IgG1 as no parallel changes of the corresponding glycans in the cellular glycan pool were observed. Interestingly, several other cytokines and molecules known to affect B-cell biology and antibody production did not have an impact on IgG1 Fc-coupled glycan profiles. Together, these data indicate that different stimuli received by B cells during their activation and differentiation can modulate the Fc-linked glycosylation of secreted IgG1 without affecting the general cellular glycosylation machinery. Our study, therefore, furthers our understanding of the regulation of IgG1 glycosylation at the cellular level.  相似文献   
995.
Male Sprague Dawley rats were exposed to EMP irradiation of 100?kV/m peak-to-peak e-field intensity and different numbers of pulses. Rat sperm samples were prepared for analysis of sperm qualities; Testes were assessed by transmission electron microscopy and serum hormone concentrations were examined by radioimmunoassay; Enzymatic activities of Total-superoxide dismutase(T-SOD) and manganese-superoxide dismutase (MnSOD), the mRNA levels of MnSOD and cuprozinc-superoxide dismutase (CuZnSOD), and the density of malondialdehyde (MDA) were also determined. EMP irradiation did not affect spermatozoon morphology, micronucleus formation rate, sperm number or viability, but the acrosin reaction rate decreased at 24?h and 48?h and recovered by 72?h after irradiation as compared to the controls. The ultrastructure of rat testis displayed more serious damage at 24?h than at other time points (6?h, 12?h, 48?h). Serum levels of luteotrophic hormone (LH) and testosterone (T) were elevated in irradiated rats as compared to controls. After irradiation, enzymatic activities of T-SOD and MnSOD were reduced by 24?h, consistent with the changes observed in MnSOD mRNA expression; MDA content increased at 6?h in turn. These studies have quantified the morphological damage and dysfunction in the rat reproductive system induced by EMP. The mechanism of EMP induced damage may be associated with the inhibition of MnSOD expression.  相似文献   
996.
997.
998.
A missense mutation in PPARD causes a major QTL effect on ear size in pigs   总被引:2,自引:0,他引:2  
Ren J  Duan Y  Qiao R  Yao F  Zhang Z  Yang B  Guo Y  Xiao S  Wei R  Ouyang Z  Ding N  Ai H  Huang L 《PLoS genetics》2011,7(5):e1002043
Chinese Erhualian is the most prolific pig breed in the world. The breed exhibits exceptionally large and floppy ears. To identify genes underlying this typical feature, we previously performed a genome scan in a large scale White Duroc × Erhualian cross and mapped a major QTL for ear size to a 2-cM region on chromosome 7. We herein performed an identical-by-descent analysis that defined the QTL within a 750-kb region. Historically, the large-ear feature has been selected for the ancient sacrificial culture in Erhualian pigs. By using a selective sweep analysis, we then refined the critical region to a 630-kb interval containing 9 annotated genes. Four of the 9 genes are expressed in ear tissues of piglets. Of the 4 genes, PPARD stood out as the strongest candidate gene for its established role in skin homeostasis, cartilage development, and fat metabolism. No differential expression of PPARD was found in ear tissues at different growth stages between large-eared Erhualian and small-eared Duroc pigs. We further screened coding sequence variants in the PPARD gene and identified only one missense mutation (G32E) in a conserved functionally important domain. The protein-altering mutation showed perfect concordance (100%) with the QTL genotypes of all 19 founder animals segregating in the White Duroc × Erhualian cross and occurred at high frequencies exclusively in Chinese large-eared breeds. Moreover, the mutation is of functional significance; it mediates down-regulation of β-catenin and its target gene expression that is crucial for fat deposition in skin. Furthermore, the mutation was significantly associated with ear size across the experimental cross and diverse outbred populations. A worldwide survey of haplotype diversity revealed that the mutation event is of Chinese origin, likely after domestication. Taken together, we provide evidence that PPARD G32E is the variation underlying this major QTL.  相似文献   
999.
1000.
Gao J  Hu Z  Zhao Z  Liu G  Ren Y  Chen G 《The protein journal》2011,30(8):521-528
In the present study, we designed a novel targeted multi-functional fusion protein LHAD composed of LL-37, FXa recognition peptide, hirudin-12-residue, AAP, and RGD peptide. It was expressed in the Pichia pastoris GS115 strain and purified by affinity chromatography. The in vitro studies suggested that the novel designed protein exhibited antibacterial activity, anti-platelet aggregation and anti-thrombin activities. Moreover, the capability of anti-thrombin was significantly increased compared to that of natural hirudin. Our study may provide a potential approach to design multi-functional drugs for the prevention and management of thrombosis.  相似文献   
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