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681.
Two new metabolites, including a lindenane-type sesquiterpenoid, menelloide C (1), and a germacrane-type sesquiterpenoid, menelloide D (2), were isolated from a Formosan gorgonian coral identified as Menella sp. The structures of 1 and 2 were established by spectroscopic methods and 2 displayed a weak inhibitory effect on the release of elastase by human neutrophils. 相似文献
682.
Kao CY Su JH Lu MC Hwang TL Wang WH Chen JJ Sheu JH Kuo YH Weng CF Fang LS Wen ZH Sung PJ 《Marine drugs》2011,9(8):1319-1331
Five new cembrane-type diterpenoids, lobocrassins A-E (1-5), were isolated from the soft coral Lobophytum crassum. The structures of cembranes 1-5 were established by spectroscopic and chemical methods and by comparison of the spectral data with those of known cembrane analogues. Lobocrassin A (1) is the first cembranoid possessing an α-chloromethyl-α-hydroxy-γ-lactone functionality and is the first chlorinated cembranoid from soft corals belonging to the genus Lobophytum. Lobocrassins B (2) and C (3) were found to be the stereoisomers of the known cembranes, 14-deoxycrassin (6) and pseudoplexaurol (7), respectively. Lobocrassin B (2) exhibited modest cytotoxicity toward K562, CCRF-CEM, Molt4, and HepG2 tumor cells and displayed significant inhibitory effects on the generation of superoxide anion and the release of elastase by human neutrophils. 相似文献
683.
You-seok Kim Kyoung-won Seo Jong-hwa Lee Eun-wha Choi Hee-woo Lee Cheol-yong Hwang Nam-shik Shin Hee-jeong Youn Hwa young Youn 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(1):85-87
Blood, saliva, and nail samples were collected from 54 dogs and 151 cats and analyzed for the presence of Bartonella henselae with a novel nested polymerase chain reaction (PCR) method. Bartonella (B.) henselae was detected in feral cat blood (41.8%), saliva (44.1%), and nail (42.7%) samples. B. henselae was also detected in pet cat blood (33.3%), saliva (43.5%), and nail (29.5%) samples and in pet dog blood (16.6%), saliva (18.5%), and nail (29.6%) samples. Nine samples were infected with B. clarridgeiae and 2 were co-infected with B. henselae and B. clarridgeiae of blood samples of dogs. This report is the first to investigate the prevalence of B. henselae and B. clarridgeiae in dogs and cats in Korea, and suggests that dogs and cats may serve as potential Bartonella reservoirs. 相似文献
684.
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
685.
Zhi-Qiang Chang Joong-Su Lee Mi-Hyun Hwang Joo-Heon Hong Hee-Kyoung Jung Sam-Pin Lee Seung-Chun Park 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(2):165-167
The effect of extracellular β-(1→3), (1→6)-glucan, produced by Paenibacillus polymyxa JB115, on nitric oxide (NO) production in RAW264.7 macrophages was investigated. β-glucan induced the production of NO by RAW264.7 macrophages in a concentration- and time-dependent manner. Moreover, β-glucan stimulation increased the mRNA expression of iNOS, COX-2 and IL-6 in RAW264.7 macrophages in a concentration-dependent manner. 相似文献
686.
Estimation of instantaneous and daily net radiation from MODIS data under clear sky conditions: a case study in East Asia 总被引:2,自引:0,他引:2
The Moderate Resolution Imaging Spectroradiometer-based net radiation (R N) model was built and applied in East Asia in 2005. Because there have hardly been simple parameterization schemes developed over a large area using remote-sensing technology, the model was aimed to present physical simplicity in complex topography at multiple spatiotemporal scales. The model successfully reproduced the instantaneous R N values obtained at four flux tower sites having individually different ecohydrology. The diurnal cycle of R N was contextually simulated using a simple sine curve to determine the daily and monthly average net radiation. The diurnal R N estimation method was proven to be a reliable model as long as accurate boundary conditions, sunrise and sunset times, for example, were obtained. The monthly average net radiation (MANR) was estimated using the diurnal patterns of the instantaneous R N. Distribution of the monthly R N demonstrated that elevation and latitude were the primary factors affecting the MANR. The proposed R N algorithm turned out to be a promising method for valuable applications in various fields due to systematic simplicity and fewer input parameters. 相似文献
687.
Nelson M Lowes K Hwang V;members of the Nutrition Group School Meals Review Panel Department for Education Skills 《Public health nutrition》2007,10(7):652-662
OBJECTIVES: To undertake secondary analyses of the 1997 National Diet and Nutrition Survey of Young People aged 4-18 years in order to describe the contribution of school meals to daily food and nutrient intakes; and to compare the findings from 1997 with data collected in English primary and secondary schools in 2004-2005. DESIGN: Cross-sectional analysis of 7-day weighed inventory food consumption data according to age, sex, household income, free school meals and breakfast consumption. Comparison of food consumption with the Balance of Good Health and of nutrient intake data with the Caroline Walker Trust (CWT) guidelines. SETTING: United Kingdom. SUBJECTS: One thousand four hundred and fifty-six UK schoolchildren aged 4-18 years, 7058 English primary-school pupils and 5695 English secondary-school pupils. RESULTS: Pupils' school meal choices in 1997 did not accord with the Balance of Good Health. Food choices in school were less healthy than choices outside school. School meals failed to make good the shortfalls in daily intakes of non-starch polysaccharides and zinc in primary-school pupils, and of calcium, iron, zinc, vitamin A and non-starch polysaccharides in secondary-school pupils, nor excess daily intakes of saturated fatty acids, non-milk extrinsic sugars and sodium at all ages. School meals typically failed to meet CWT guidelines. They were more likely to meet CWT guidelines when choice of foods was restricted. CONCLUSIONS: School meals need substantial improvement to meet CWT guidelines for healthy eating. The introduction of food-based guidelines for school meals in England in 2001 did not improve the food choices in school meals. 相似文献
688.
Juan Carlos Molinero Li‐Chun Tseng Lucia Lopez‐Lopez Ulrich Sommer Sami Souissi Jiang‐Shiou Hwang 《Fisheries Oceanography》2016,25(6):555-564
Global environmental changes threaten the sustainable use of resources and raise uncertainties regarding marine populations' responses in a changing Ocean. The pelagic copepods of the genus Calanus play a central role in shelf ecosystems transferring phytoplankton carbon to harvested populations, from boreal to temperate regions. Here we examined a 15‐yr time series of Calanus sinicus abundance in regards to climate forcing in the East China Sea. We identified a compound effect of the Pacific Decadal Oscillation (PDO) and the East Asian Winter Monsoon (EAWM) on environmental conditions in the East China Sea. Such climate influences not only a southward transport of C. sinicus from its population centres into the Taiwan area, but favours advantageous thermal conditions for the species as well. On the interannual scale, our results show that the population size of C. sinicus echoes climate‐driven temperature changes. Hence, the possibility of using the PDO and EAWM variability for assessing and predicting interannual abundance changes of C. sinicus in the East China Sea is considered. The observed close relationship between climate and C. sinicus may promote bottom‐up controls in the pelagic food web, further influencing the southern edge of the species' geographic distribution. Owing to the prominent role this species plays in food web dynamics these results might help integrative fisheries management policies in the heavily exploited East China Sea. 相似文献
689.
Effect of host and non‐host crops on Plasmodiophora brassicae resting spore concentrations and clubroot of canola
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S. F. Hwang H. U. Ahmed Q. Zhou G. D. Turnbull S. E. Strelkov B. D. Gossen G. Peng 《Plant pathology》2015,64(5):1198-1206
Plasmodiophora brassicae, causal agent of clubroot of crucifers, poses a serious threat to Canadian canola production. The effects of fallow (F) periods and bait crops (clubroot‐susceptible canola (B) and perennial ryegrass (R)) on clubroot severity and P. brassicae resting spore populations were evaluated in five sequences: R–B, B–R, R–F, B–F and F–F. Both host and non‐host bait crops reduced clubroot severity in a subsequent crop of a susceptible canola cultivar compared with fallow. Resting spore and P. brassicae DNA concentrations decreased in all treatments, but were lowest for the R–B and B–R bait crop sequences. In addition, two studies were conducted in mini‐plots under field conditions to assess the effect of rotation of susceptible or resistant canola cultivars on clubroot severity and P. brassicae resting spore populations. One study included three crops of susceptible canola compared with a 2‐year break of oat–pea, barley–pea, wheat–wheat or fallow–fallow. The other study assessed three crops of resistant canola, two crops of resistant canola with a 1‐year break, one crop of resistant canola and a 2‐year break, and a 3‐year break with barley followed by a susceptible canola. The rotations that included non‐host crops of barley, pea or oat reduced clubroot severity and resting spore concentrations, and increased yield, compared with continuous cropping of either resistant or susceptible canola. Growing of a susceptible canola cultivar contributed 23–250‐fold greater gall mass compared with resistant cultivars. 相似文献
690.
Jinsheng Cui Eunji Kim Dong Hyun Moon Tae Ho Kim Ilnam Kang Yeonjung Lim Daniel Shin Sunghoon Hwang Young Eun Du Myoung Chong Song Munhyung Bae Jang-Cheon Cho Jichan Jang Sang Kook Lee Yeo Joon Yoon Dong-Chan Oh 《Marine drugs》2022,20(6)
Two new lipo-decapeptides, namely taeanamides A and B (1 and 2), were discovered from the Gram-positive bacterium Streptomyces sp. AMD43, which was isolated from a mudflat sample from Anmyeondo, Korea. The exact molecular masses of 1 and 2 were revealed by high-resolution mass spectrometry, and the planar structures of 1 and 2 were elucidated using NMR spectroscopy. The absolute configurations of 1 and 2 were determined using a combined analysis of 1H-1H coupling constants and ROESY correlations, the advanced Marfey’s method, and bioinformatics. The putative nonribosomal peptide synthetase pathway for the taeanamides was identified by analyzing the full genome sequence data of Streptomyces sp. AMD43. We also found that taeanamide A exhibited mild anti-tuberculosis bioactivity, whereas taeanamide B showed significant bioactivity against several cancer cell lines. 相似文献