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71.
Danggui Buxue Tang (DBT) is a traditional Chinese herbal decoction containing Radix Astragali and Radix Angelicae sinensis. Pharmacological results indicate that DBT can stimulate bone cell proliferation and differentiation. The aim of the study was to investigate the efficacy of adding DBT to bone substitutes on bone regeneration following bone injury. DBT was incorporated into porous composites (GGT) made from genipin-crosslinked gelatin and β-triclacium phosphates as bone substitutes (GGTDBT). The biological response of mouse calvarial bone to these composites was evaluated by in vivo imaging systems (IVIS), micro-computed tomography (micro-CT), and histology analysis. IVIS images revealed a stronger fluorescent signal in GGTDBT-treated defect than in GGT-treated defect at 8 weeks after implantation. Micro-CT analysis demonstrated that the level of repair from week 4 to 8 increased from 42.1% to 71.2% at the sites treated with GGTDBT, while that increased from 33.2% to 54.1% at GGT-treated sites. These findings suggest that the GGTDBT stimulates the innate regenerative capacity of bone, supporting their use in bone tissue regeneration.  相似文献   
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The antioxidant properties of cinnamophilin were evaluated by studying its ability to react with relevant reactive oxygen species, and its protective effect on cultured cells and biomacromolecules under oxidative stress. Cinnamophilin concentration-dependently suppressed non-enzymatic iron-induced lipid peroxidation in rat brain homogenates with an IC50 value of 8.0+/-0.7 microM and iron ion/ADP/ascorbate-initiated rat liver mitochondrial lipid peroxidation with an IC50 value of 17.7+/-0.2 microM. It also exerted an inhibitory activity on NADPH-dependent microsomal lipid peroxidation with an IC50 value of 3.4+/-0.1 microM without affecting microsomal electron transport of NADPH-cytochrome P-450 reductase. Both 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azo-bis(2-amidinopropane) dihydrochloride-derived peroxyl radical tests demonstrated that cinnamophilin possessed marked free radical scavenging capacity. Cinnamophilin significantly protected cultured rat aortic smooth muscle cells (A7r5) against alloxan/iron ion/H2O2-induced damage resulting in cytoplasmic membranous disturbance and mitochondrial potential decay. By the way, cinnamophilin inhibited copper-catalyzed oxidation of human low-density lipoprotein, as measured by fluorescence intensity and thiobarbituric acid-reactive substance formation in a concentration-dependent manner. On the other hand, it was reactive toward superoxide anions generated by the xanthine/xanthine oxidase system and the aortic segment from aged spontaneously hypertensive rat. Furthermore, cinnamophilin exerted a divergent effect on the respiratory burst of human neutrophil by different stimulators. Our results show that cinnamophilin acts as a novel antioxidant and cytoprotectant against oxidative damage.  相似文献   
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Continuing study of the ethyl acetate (EtOAc) extract of the cultured soft coral Sinularia brassica afforded five new withanolides, sinubrasolides H–L (15). The structures of the new compounds were elucidated on the basis of spectroscopic analysis. The cytotoxicities of new compounds 15 and a known compound sinubrasolide A (6) against the proliferation of a limited panel of cancer cell lines were assayed. The anti-inflammatory activities of compounds 16 were evaluated by measuring their ability to suppress N-formyl-methionyl-leucyl-phenyl-alanine/cytochalasin B (fMLP/CB)-induced superoxide anion generation and elastase release in human neutrophils.  相似文献   
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Phytophthora capsici is a devastating disease of pepper (Capsicum sp.) in Taiwan causing complete loss of commercial fields. The objective of this study was to characterize genetic diversity for 38 newly collected isolates and three historical isolates. Analysis of data includes whole genome sequence for two new isolates and for two isolates collected previously in 1987 and 1995. In addition, 63 single nucleotide polymorphism loci were genotyped using targeted-sequencing, revealing 27 unique genotypes. Genotypes fell into three genetic groups: two of the groups contain 90% (n = 33) of the 2016 isolates, are triploid (or higher), are exclusively the A2 mating type and appear to be two distinct clonal lineages. The isolates from 2016 that grouped with the historical isolates are diploid and the A1 mating type. Whole genome sequence revealed that ploidy varies by linkage group, and it appears the A2 clonal lineages may have switched mating type due to increased ploidy. Most of the isolates were recently race-typed on a set of differential C. annuum, and although there was no direct correlation between virulence and ploidy, many of the triploid isolates were less virulent as compared to the historical diploid isolates. The implications for breeding resistant pepper and conducting population analyses are discussed.  相似文献   
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The free radical scavenging and anti-cancer activites of Pinus morrisonicola Hay. were studied using different parts of the pine, namely, needle, bark and cone. Results showed that pine needle water extract has the highest scavenging superoxide anion activity and the lowest IC50 value in inhibiting superoxide anion formation; however, the bark water extract showed the best anti-lipid peroxidation activity. Additionally, needle water extract displayed the highest inhibition of leukemia cell line U937 growth. The results indicated that P. morrisonicola Hay. possesses potential chemopreventative and therapeutic properties.  相似文献   
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Liver progenitors, so-called oval cells, proliferate remarkably from periportal areas after severe liver injury when hepatocyte regeneration is compromised. These cells invade far into the liver parenchyma. Molecular mechanisms underlying these behaviors of oval cells remain poorly understood. In this study, we treated rats with 2-acetylaminofluorene/carbon tetrachloride to induce hepatic oval cells. By expression microarray analysis, we investigated global gene expression profiles in liver tissue, with an emphasis on adhesion molecules, extracellular matrix proteins, matrix metalloproteinases (MMPs), growth factors/cytokines, and receptors that might contribute to the distinct behaviors of oval cells. Genes upregulated at least twofold were selected. We then performed immunostaining to verify the microarray results and identified expression of MMP-7 and CD44 in oval cells. Staining of cytokeratin (CK)-19, an oval-cell marker, was similar between oval cells located next to periportal areas and those located far within the parenchyma. In contrast, CD44 staining was more intense in the parenchyma than in periportal areas, suggesting a role of CD44 in oval-cell invasion. Moreover, newly differentiated CK-19+ hepatocytes within foci did not show CD44 staining, suggesting that CD44 is related to the undifferentiated oval-cell phenotype. We then investigated oval-cell reactivity in CD44-deficient mice fed an oval cell-inducing diet of 3,5-diethoxycarbonyl-1,4-dihydrocollidine. Results showed significantly reduced oval-cell reactivity in CD44-deficient mice. Thus, oval cells express MMP-7 and CD44, and CD44 appears to play critical roles in the proliferation, invasion, and differentiation of hepatic oval cells in rodents.  相似文献   
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