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31.
In the present study, the ethanolic extracts from the heartwood of Acacia confusa, a species indigenous to Taiwan, exhibit strong antioxidant effects. Among all the fractions from ethanolic extracts of heartwood, the EtOAc soluble fraction exhibits the best antioxidant activity. The 80% 1,1-diphenyl-2-picrylhydrazyl radical inhibitory activity by the EtOAc extract was observed at a concentration of 5 mug/mL, and at the same dosage there was a similar free radical scavenging activity for (-)-ascorbic acid and (+)-catechin, both of which are well-known antioxidants. In addition, the EtOAc extract also protects PhiX174 supercoiled DNA against strand scission induced by hydroxyl radical. Furthermore, following by column chromatography and reverse-phase high-performance liquid chromatorgrapy, 10 pure phenolic compounds, including three major antioxidants (3,7,8,3',4'-pentahydroxyflavone, 7,8,3',4'-tetrahydroxy-3-methoxyflavone, and 3,4,2',3',4'-pentahydroxy-trans-chalcone) and a new flavonoid (3,7,8,3'-tetrahydroxy-4'-methoxyflavone), were isolated from the ethanolic extracts of A. confusa heartwood.  相似文献   
32.
A powerful 7.3 magnitude earthquake struck Taiwan on September 21, 1999. The stream water chemistry (pH, total alkalinity, conductivity, sodium, potassium, calcium, magnesium, ammonium, fluoride, chloride, sulfate, and nitrate) has been monitored since 1995 at the Guandaushi forestry riparian zone in central Taiwan. Collected data was used as a basis for comparing pre- and post-earthquake impacts. The pH, conductivity, and concentrations of Na, Ca, Mg, SO4, and HCO3 in stream water were lowest during the summer season, when stream water discharge was highest. On the other hand, the lowest concentrations of Cl, NH4, and NO3 in stream water occurred during the winter season, when stream water discharge was lowest. Also, K and F showed very little seasonal fluctuation in concentration. Downward trends in K and Ca were found 14 months prior to the earthquake; although, an upward trend occurred in NH4 at the same time.  相似文献   
33.
A recombinant fowlpox virus (rFPV/VP2) expressing infectious bursal diseases virus (IBDV) VP2 gene has been constructed. After purification and identification of rFPV/VP2, the adjuvant activity of the recombinant chicken IL-12 (rchIL-12), synthesized by our previous construct of rFPV/chIL-12, in rFPV/VP2-expressed rVP2 antigen was assessed in one-week-old specific-pathogen free chickens. The results indicated that rchIL-12 alone or rchIL-12 plus mineral oil (MO) co-administered with rVP2 antigen significantly enhanced the production of serum neutralization (SN) antibody against IBDV, compared to those with MO alone. The SN titers in groups receiving rVP2 antigen with MO alone were more inconsistent after vaccination. On the other hand, rchIL-12 significantly stimulated IFN-γ production in serum and in splenocyte cultured supernatant, suggesting that rchIL-12 alone or plus MO significantly induced a cell-mediated immune response. Finally, bursal lesion protection from very virulent IBDV (vvIBDV) challenge in chickens receiving rVP2 antigen with rchIL-12 alone or plus MO was much more effective than that with MO alone at two weeks after boosting. Taken together, rchIL-12 alone augmented in vivo the induction of a primary and also a secondary SN antibody production and a cell-mediated immunity against IBDV rVP2 antigen, which conferred the enhancement of bursal lesion protective efficacy from vvIBDV challenge. These data indicated that a potential for chIL-12 as immunoadjuvant for chicken vaccine development such as IBDV rVP2 antigen.  相似文献   
34.
Betanin is an antioxidant pigment found in djulis, a grain native to Taiwan, and is a natural source food coloring, but the bright red color degrades rapidly if submitted to light, heat, or oxygen. The effects of nanogrinding on the stability of pigments and bioactive components are unknown. In this study, the color characteristics and bioactivity (antioxidant capacity and enzyme activity) of nanoparticle (NP) djulis was compared with those of intact granules (IG) and microparticles (MP). Results showed that the NP samples exhibited the highest betanin content (2.04 mg/g), which was almost twice that of IG. It was observed that nanogrinding resulted in higher pigment extraction efficiency. However, during storage (5-35 °C for 56 days), NP samples showed the most serious pigment degradation, and this color degradation, as expected, had the lowest activation energy. This was more evident when the storage temperature was high. Antioxidant capacities showed the same trends. MP and NP exhibited significantly higher activity of superoxide dismutaste-like activity, lactoperoxidase (LPO), and lysozyme than IG. Gel permeation chromatography confirmed the degradation of larger particles during nanogrinding, which might favor enzyme extraction and their activities. Statistical analysis revealed a close relationship between betanin and antioxidant capacity.  相似文献   
35.
It is well recognized that bone marrow stromal cells (MSCs) can differentiate into neuron-like cells when supplemented with growth factors and/or chemical treatments. We demonstrated that primary MSCs obtained from adult rats could spontaneously differentiate into neural precursor cells after long-term culture. During the outset of in vitro culture, less than 0.1% of adult rat primary MSCs expressed nestin, the common protein of neural precursors. These MSCs didn't show neuronal morphology nor express neuronal antigens. In contrast, after continuous maintenance for 6 weeks, a significant subpopulation of MSCs formed cellular clumps and expressed nestin (32.3 +/- 6.3%). Less than 0.1% of cells expressing immature neuron marker betaIII-tubulin could be detected in these prolonged cultured MSCs. After serum deprivation and growth factor supplement, these nestin-positive cells could express neuron-like morphology and neuron-specific markers NF-H, betaIII-tubulin, tau, and neurotransmitter GABA. In contrast, the MSCs without prolonged culture didn't show neuronal morphology nor neuronal markers even after serum withdrawal and growth factors stimulation. These results demonstrated that neural precursors could be obtained from long-term cultured MSCs, and suggested that MSCs should be useful as a potential source for treatment of neurological disease.  相似文献   
36.
Circulating monocytes and tissue macrophages were suggested to be susceptible to avian reovirus (ARV) infection. To determine if ARV infects and replicates in mononuclear phagocytes (KUL01-positive cells), we infected 3-day-old specific-pathogen-free chickens with ARV strain 2408 by inoculation of the left footpad. The left footpads and spleens were collected for analysis at 1.5 and 2.5 d after inoculation. Replication of ARV in the footpad and spleen was demonstrated by detection of the viral protein σNS using immunohistochemical testing and viral S1 RNA expression by real-time quantitative polymerase chain reaction (qPCR). Furthermore, immunofluorescent double-staining assay of cytocentrifuged cells and cryosections of the footpad and spleen for the viral protein σNS and the surface marker recognized by monoclonal antibody (MAb) KUL01 indicated that KUL01-positive cells costained with MAb H1E1, which recognizes ARV protein σNS. In addition, more ARV S1 RNA was measured by qPCR in the KUL01-positive cell samples prepared from the footpad or spleen 1.5 d after inoculation compared with non-KUL01-positive cell samples. The amounts of ARV S1 RNA in the spleen were significantly lower (P < 0.05) than the amounts in the footpad 1.5 d after inoculation. The results suggest that ARV infects mononuclear phagocytes and then replicates within these cells before migrating to the spleen, where it infects and replicates in KUL01-positive cells.  相似文献   
37.
Chronic neuroinflammation plays an important role in the development and maintenance of neuropathic pain. The compound flexibilide, which can be obtained from cultured soft coral, possesses anti-inflammatory and analgesic effects in the rat carrageenan peripheral inflammation model. In the present study, we investigated the antinociceptive properties of flexibilide in the rat chronic constriction injury (CCI) model of neuropathic pain. First, we found that a single intrathecal (i.t.) administration of flexibilide significantly attenuated CCI-induced thermal hyperalgesia at 14 days after surgery. Second, i.t. administration of 10-μg flexibilide twice daily was able to prevent the development of thermal hyperalgesia and weight-bearing deficits in CCI rats. Third, i.t. flexibilide significantly inhibited CCI-induced activation of microglia and astrocytes, as well as the upregulated proinflammatory enzyme, inducible nitric oxide synthase, in the ipsilateral spinal dorsal horn. Furthermore, flexibilide attenuated the CCI-induced downregulation of spinal transforming growth factor-β1 (TGF-β1) at 14 days after surgery. Finally, i.t. SB431542, a selective inhibitor of TGF-β type I receptor, blocked the analgesic effects of flexibilide in CCI rats. Our results suggest that flexibilide may serve as a therapeutic agent for neuropathic pain. In addition, spinal TGF-β1 may be involved in the anti-neuroinflammatory and analgesic effects of flexibilide.  相似文献   
38.
39.
Chemical investigation of a Red Sea Spongia sp. led to the isolation of four new compounds, i.e., 17-dehydroxysponalactone (1), a carboxylic acid, spongiafuranic acid A (2), one hydroxamic acid, spongiafuranohydroxamic acid A (3), and a furanyl trinorsesterpenoid 16-epi-irciformonin G (4), along with three known metabolites (−)-sponalisolide B (5), 18-nor- 3,17-dihydroxy-spongia-3,13(16),14-trien-2-one (6), and cholesta-7-ene-3β,5α-diol-6-one (7). The biosynthetic pathway for the molecular skeleton of 1 and related compounds was postulated for the first time. Anti-inflammatory activity of these metabolites to inhibit superoxide anion generation and elastase release in N-formyl-methionyl-leucyl phenylalanine/cytochalasin B (fMLF/CB)-induced human neutrophil cells and cytotoxicity of these compounds toward three cancer cell lines and one human dermal fibroblast cell line were assayed. Compound 1 was found to significantly reduce the superoxide anion generation and elastase release at a concentration of 10 μM, and compound 5 was also found to display strong inhibitory activity against superoxide anion generation at the same concentration. Due to the noncytotoxic activity and the potent inhibitory effect toward the superoxide anion generation and elastase release, 1 and 5 can be considered to be promising anti-inflammatory agents.  相似文献   
40.
Two new isosarcophine derivatives, cherbonolides M (1) and N (2), were further isolated from a Formosan soft coral Sarcophyton cherbonnieri. The planar structure and relative configuration of both compounds were established by the detailed analysis of the IR, MS, and 1D and 2D NMR data. Further, the absolute configuration of both compounds was determined by the comparison of CD spectra with that of isosarcophine (3). Notably, cherbonolide N (2) possesses the unique cembranoidal scaffold of tetrahydrooxepane with the 12,17-ether linkage fusing with a γ-lactone. In addition, the assay for cytotoxicity of both new compounds revealed that they showed to be noncytotoxic toward the proliferation of A549, DLD-1, and HuCCT-1 cell lines. Moreover, the anti-inflammatory activities of both metabolites were carried out by measuring the N-formyl-methionyl-leucyl-phenylalanine/cytochalasin B (fMLF/CB)-induced generation of superoxide anion and elastase release in the primary human neutrophils. Cherbonolide N (2) was found to reduce the generation of superoxide anion (20.6 ± 6.8%) and the elastase release (30.1 ± 3.3%) in the fMLF/CB-induced human neutrophils at a concentration of 30 μM.  相似文献   
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