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751.
Leukotrienes (LT) and chemokines are important chemotactic compounds in regulating the recruitment and activation of immune cells during pulmonary inflammatory reactions. Results showed that LTC4 release by porcine alveolar epithelial type II cells (AEC IIs) is significantly enhanced by either LTB4 or LPS stimulation. The basal level of IL-8 gene expression in AEC IIs was only 1/3 of that observed in alveolar macrophages (AMs) while AEC IIs expressed a higher basal level of monocyte chemotactic peptide-1 (MCP-1) and also in response to LPS stimulation than do AMs. The increasing basal and LT-induced MCP-1 gene expressions after 8h of incubation were observed in AEC IIs but decreased in AMs. These findings suggest that AEC IIs play an important role in initial inflammatory reactions of the lung by releasing LTC4, and that they also modulate later inflammatory reactions, evidenced by consistent elevation of MCP-1 gene expression after and during exogenous challenge in pigs. 相似文献
752.
Hyun Sun Cho Seung Hee Chang Youn Sun Chung Ji Young Shin Sung Jin Park Eun Sun Lee Soon Kyung Hwang Jung Taek Kwon Arash Minai Tehrani Minah Woo Mi Sook Noh Huda Hanifah Hua Jin Cheng Xiong Xu Myung Haing Cho 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(1):23-28
Tetrandrine (TET), a bis-benzylisoquinoline alkaloid from the root of Stephania tetrandra, is known to have anti-tumor activity in various malignant neoplasms. However, the precise mechanism by which TET inhibits tumor cell growth remains to be elucidated. The present studies were performed to characterize the potential effects of TET on phosphoinositide 3-kinase/Akt and extracellular signal-regulated kinase (ERK) pathways since these signaling pathways are known to be responsible for cell growth and survival. TET suppressed cell proliferation and induced apoptosis in A549 human lung carcinoma cells. TET treatment resulted in a down-regulation of Akt and ERK phosphorylation in both time-/concentration-dependent manners. The inhibition of ERK using PD98059 synergistically enhanced the TET-induced apoptosis of A549 cells whereas the inhibition of Akt using had a less significant effect. Taken together, our results suggest that TET: i) selectively inhibits the proliferation of lung cancer cells by blocking Akt activation and ii) increases apoptosis by inhibiting ERK. The treatment of lung cancers with TET may enhance the efficacy of chemotherapy and radiotherapy and increase the apoptotic potential of lung cancer cells. LY294002相似文献
753.
754.
Lee SJ Ahn JK Khanh TD Chun SC Kim SL Ro HM Song HK Chung IM 《Journal of agricultural and food chemistry》2007,55(23):9415-9421
We determined and compared the composition and content of isoflavones in the cotyledon, hypocotyl, and root of 17 soybean sprout varieties grown under dark and light conditions. The total average isoflavone concentrations in 17 soybean sprout varieties were 2167 microg g(-1) (green sprout) and 2538 microg g(-1) (yellow sprout) in cotyledons, 1169 microg g(-1) (green sprout) and 1132 microg g(-1) (yellow sprout) in hypocotyls, and 2399 microg g(-1) (green sprout) and 2852 microg g(-1) (yellow sprout) in roots. There were no significant differences in total isoflavone concentrations between the green and yellow sprouts. However, significant differences in total isoflavone amounts were observed among the three organs, with roots exhibiting the highest total isoflavone concentrations followed by cotyledons and hypocotyls. Total daidzin concentrations of green (775 microg g(-1)) and yellow (897 microg g(-1)) sprouts increased to more than 4 times that in seeds (187 microg g(-1)). Yellow sprouts contained the highest (1122 microg g(-1)) total genistin concentrations, and green (155 microg g(-1)) and yellow (155 microg g(-1)) sprouts had more total glycitin concentrations than seeds. In cotyledons of green and yellow sprouts, genistin, daidzen, and glycitin constituted more than 67%, more than 28%, and less than 4% of the total isoflavone contents, respectively. In hypocotyls, total daidzin represented more than 45% of the total isoflavones, and total glycitin was higher than in cotyledons and roots. Malonylglycoside concentrations were highest in cotyledons, whereas glycoside concentrations were highest in hypocotyls and roots. The high accumulation of isoflavones in roots is consistent with isoflavones serving as signal molecules in the induction of microbial genes involved in soybean (Glycine max) nodulation. 相似文献
755.
Inhibition of the pathogenicity of Magnaporthe grisea by bromophenols, isocitrate lyase inhibitors, from the red alga Odonthalia corymbifera 总被引:1,自引:0,他引:1
Lee HS Lee TH Lee JH Chae CS Chung SC Shin DS Shin J Oh KB 《Journal of agricultural and food chemistry》2007,55(17):6923-6928
Magnaporthe grisea is a fungal pathogen of rice that forms appressoria that penetrate the outer cuticle of the rice plant. Data from recent studies indicate that M. grisea isocitrate lyase (ICL), a key enzyme in the glyoxylate cycle, is highly expressed during appressorium-mediated plant infection. Bromophenols isolated from the red alga Odonthalia corymbifera exhibited potent ICL inhibitory activity and blocked appressoria formation by M. grisea in a concentration-dependent manner. In addition, these compounds protected the rice plants from infection by M. grisea. Rice plants infected with wild-type M. grisea Guy 11 exhibited significantly lower disease severity with bromophenol treatment than without, and the treatment effect was comparable to the behavior of the Deltaicl knockout mutant I-10. The protective effect of bromophenols and their strong inhibition of appressorium formation on rice plants suggest that ICL inhibitors may be promising candidates for crop protection, particularly to protect rice plants against M. grisea. 相似文献
756.
Different central manifestations in response to electroacupuncture at analgesic and nonanalgesic acupoints in rats: a manganese-enhanced functional magnetic resonance imaging study 总被引:6,自引:0,他引:6 下载免费PDF全文
Jen-Hwey Chiu Mao-Shu Chung Hui-Cheng Cheng Tzu-Cheng Yeh Jen-Chuen Hsieh Chung-Yen Chang Wan-Yo Kuo Henrich Cheng Low-Tone Ho 《Canadian journal of veterinary research》2003,67(2):94-101
Acupuncture analgesia is an important issue in veterinary medicine. This study was designed to elucidate central modulation effects in response to electroacupuncture (EA) at different acupoints. Manganese-enhanced functional magnetic resonance imaging was performed in Sprague-Dawley rats after sham acupuncture, sham EA, or true EA at somatic acupoints. The acupoints were divided into 3 groups: group 1, analgesic acupoints commonly used for pain relief, such as Hegu (LI 4); group 2, nonanalgesic acupoints rarely used for analgesic effect, such as Neiguan (PC 6); and group 3, acupoints occasionally used for analgesia, such as Zusanli (ST 36). Image acquisition was performed on a 1.5-T superconductive clinical scanner with a circular polarized extremity coil. The results showed that there was no neural activation caused by EA at a true acupoint with shallow needling and no electric current (sham acupuncture). When EA at a true acupoint was applied with true needling but no electric current (sham EA), there was only a slight increase in brain activity at the hypothalamus; when EA was applied at a true acupoint with true needling and an electric current (true EA), the primary response at the hypothalamus was enhanced. Also, there was a tendency for the early activation of pain-modulation areas to be prominent after EA at analgesic acupoints as compared with nonanalgesic acupoints. In conclusion, understanding the linkage between peripheral acupoint stimulation and central neural pathways provides not only an evidence-based approach for veterinary acupuncture but also a useful guide for clinical applications of acupuncture. 相似文献
757.
Seon Kyeong Park Jin Yong Kang Jong Min Kim Min Ji Kim Hyo Lim Lee Jong Hyun Moon Hye Rin Jeong Hyun-Jin Kim Min-Yu Chung Ho Jin Heo 《Marine drugs》2022,20(7)
To evaluate the biological effects of Porphyra tenera (P. tenera), we tried to confirm the possibility that the intake of P. tenera could modulate cognitive and intestinal functions in PM2.5-induced cognitive decline mice. P. tenera attenuated PM2.5-induced learning and memory impairment through antioxidant and anti-inflammatory effects by regulating the mitochondrial function and TLR-initiated NF-κB signaling. In addition, P. tenera effectively alleviated Aβ production/tau phosphorylation by inhibiting the JNK phosphorylation. Also, the bioactive constituents of P. tenera determined the sulfated galactan, mycosporine-like amino acids (MAAs), and chlorophyll derivatives. Moreover, the bioactive compounds of P. tenera by gut fermentation protected against gut dysbiosis and intestinal tight junction damage with a decrease in inflammatory response and short-chain fatty acid production. Based on these results, our findings suggest that P. tenera with sulfated galactan and MAAs is a potential material for cognitive function improvement. 相似文献
758.
The objectives of this research were to study the effects of slurry specific gravity, starch table slope, slurry pumping rate, and their interactions on starch recovery and purity; and to propose a small‐scale laboratory wet‐milling procedure for wheat. First‐order and second‐order response surface regression models were developed to study the effects and interactions of slurry specific gravity, starch table slope, and slurry pumping rate on starch and gluten separation for a 100‐g wheat wet‐milling procedure. The starch and starch protein content data fit the first‐order models (R2 = 0.99 and 0.96) better than the second‐order models (R2 = 0.98 and 0.93). Regression results from the first‐order models indicated that specific gravity, table slope, pumping rate, and their interactions all had a significant effect on starch yield and purity. However, these effects could be simplified as the effect of the resident time of starch and gluten slurry on the starch table and the specific gravity. Starch yield increased as resident time increased and specific gravity decreased. Protein content in starch decreased as the resident time decreased and the specific gravity increased. The separation condition with specific gravity of 3 Bé, table slope of 1.04 cm/m, and pumping rate of 50 mL/min was recommended. Under this condition, starch recovery was 85.6% and protein content of starch was 0.42%, which was similar to the 1.5‐kg laboratory methods in starch recovery. Total solids recovery was 98.1%, which is similar to that from 1.5‐kg laboratory methods. These results indicated that precision of the 100‐g wheat wet‐milling procedure was similar to that of the 1.5‐kg laboratory methods. 相似文献
759.
Mung bean, potato, and rice starch solutions (5%, w/w) were sonicated for up to 5 min after heating, and their physicochemical properties were investigated. Alkaline viscosities, including the apparent and inherent viscosities of starches, decreased. The residues of the swollen starch granules after pasting and centrifugation were also reduced prominently by sonication. Average degree of polymerization did not change with sonication. The starch paste became more transparent, and the hot paste viscosity measured at 70°C decreased remarkably. Results indicate that changes in the physicochemical properties of starch were induced by the disruption of swollen granules rather than the breakage of glucosidic linkages with sonication. 相似文献