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121.
Yu-Ping Fu Karl Egil Malterud Anne Grethe Hamre Kari Tvete Inngjerdingen Helle Wangensteen 《化学与生物多样性》2023,20(8):e202300161
Aconitum septentrionale is known to contain toxic diterpene alkaloids, while other bioactive compounds in the plant remain unclear. The aim of this study was to explore the phenolic compounds and polysaccharides from the water extract of A. septentrionale roots. Fifteen phenolic compounds were isolated and identified by NMR and MS, including fourteen known and one new dianthramide glucoside (2-[[2-(β-D-glucopyranosyloxy)-5-hydroxybenzoyl]amino]-4,5-dihydroxybenzoic acid methyl ester, 14 ). One neutral (complex of glucans with minor amounts of mannans) and two acidic polysaccharide fractions (complexes of pectic polysaccharides and glucans) were also obtained. Hydroxytyrosol ( 1 ), hydroxytyrosol-1-O-β-glucoside ( 2 ) and bracteanolide A ( 7 ) inhibited the release of nitric oxide by dendritic cells. Magnoflorine ( 8 ) and 2-[[2-(β-D-glucopyranosyloxy)-5-hydroxybenzoyl]amino]-5-hydroxybenzoic acid methyl ester ( 12 ) inhibited 15-lipoxygenase, and bracteanolide A ( 7 ) was a moderate inhibitor of xanthine oxidase. This study is the first to describe the diversity of phenolics and polysaccharides from A. septentrionale and their anti-inflammatory and anti-oxidant activities. 相似文献
122.
Nutrient-sufficient cultures of a Trondheimsfjord (Norway) cloneof the marine centric diatom Skeleionema costatum (Grev.) Clevewere grown at 75 µmol m2 s1 and 15C at24 and 12 h daylength to study diurnal variations and the effectof daylength on pigment and chemical composition, photosyntheticparameters, dark respiration rates and scaled fluorescence excitationspectra (F), the latter used as estimates for the absorptionof energy available to Photosystem II. Specific growth rateswere 1.06 and 0.56 day in 24 and 12 h daylength, respectively,while dark respiration rates were generally 85% of the net growthrate. The Chla-normalized photosynthetic coefficients PBm andaB were {small tilde}2025% higher in continuous lightthan at 12 h daylength, while the Chla:C ratio was {small tilde}15%lower (0.051 versus 0.061 w:w). Thus, the carbon-normalizedcoefficients Pcm and ac were <11% lower at 24 h than at 12h daylength. The maximum quantum yield max, the Chla:C ratioand F differed negligibly, as did the light saturation indexlk, the N:C ratio and the ratios Chlc:Chla and Fucoxanthin:Chla. PBm and lk did not exhibit diurnal variations at 24 hdaylength, and varied within 23% of the daily mean at 12 h daylength.Predictions of the daily gross photosynthetic rate based ondata for a given time of the day should thus not be >10%in error relative to an integrated value based on several datasets collected through 24 h. max was 0.0840.117 mol O2(mol photons) for gross oxygen evolution. However, ifused in mathematical models for predicting the gross and netgrowth rates (i.e. the gross and net carbon turnover rates),practical values of 0.076 and 0.040 g-at C (molphotons), respectively, should be employed. Correspondingly,values for aB and PBm should be adjusted pro rata.
1Present address: College of Marine Studies, Sjmannsveien 27,N-6008 lesund, Norway 相似文献
123.
Structure,biomass distribution,and energetics of the pelagic ecosystem in the Barents Sea: A synopsis 总被引:1,自引:0,他引:1
Egil Sakshaug Arne Bjørge Bjørn Gulliksen Harald Loeng Fritjof Mehlum 《Polar Biology》1994,14(6):405-411
Biomass distribution and energetics of trophic levels in the pelagic ecosystem of the Barents Sea are presented as averages over several years for the whole Barents Sea using data from the research programme Pro Mare in 1984–1989 and mathematical ecosystem models. Average biomasses range from more than 3 tonnes carbon km–2 (zooplankton) to 0.1 kg C km–2 (polar bears) and P/B ratios from 300 (bacteria) to 0.035 (minke whales). However, the Barents Sea ecosystem is in a far from steady state with, for instance, capelin stocks ranging from 30–700 kg C km–2 between years and cod stocks from 150–700 kg C km–2. As a general rule, the various fish stocks grow adequately, albeit at different rates, in warm years characterized by large influxes of Atlantic water and high zooplankton productivity. The skewed populations distribution which arises in warm years may lead to grave imbalances in cold years and even to the collapses of stocks, such as of capelin in the eighties. The food requirements of average-sized stocks of cod, seabirds and marine mammals correspond to more than twice the average productivity of capelin. Thus other species of pelagic fish (herring, polar cod) and zooplankton obviously play major roles as prey for these animals. 相似文献
124.
A survey of the patterns of lignicolous fungi to record occurrence of fruitbodies on fallen logs of Picea abies . has been performed. Ninetythree forest stands with different ages. ecology, and histories of management in Ser-Trendelag County, Central Norway were investigated. In each stand an investigation plot of 40 m diameter was established, in which five logs were randomly selected. Environmental variables of the logs and plots and geographical positions of the plots were recorded. The numerical methods used include detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA).
A total of 140 species of Aphyllophorales, Agaricales with eccentrically attached caps, heterobasiodomycetes, and prominent ascomycetes and deuteromycetes were registered. More than one third of the species were only found once. The main gradient in the data set was shown to be related to decay. The second gradient was related to size of the logs and some forest management variables (in addition to decay). Of the variation in composition of the species, 13.8 % can be ascribed to solely environmental variance, 6 % to solely spatial structure, and only 0.8 % to the combination of the environment and spatial component of variation. The results are discussed in the light of wood decay, forest management, and landscape fragmentation. 相似文献
A total of 140 species of Aphyllophorales, Agaricales with eccentrically attached caps, heterobasiodomycetes, and prominent ascomycetes and deuteromycetes were registered. More than one third of the species were only found once. The main gradient in the data set was shown to be related to decay. The second gradient was related to size of the logs and some forest management variables (in addition to decay). Of the variation in composition of the species, 13.8 % can be ascribed to solely environmental variance, 6 % to solely spatial structure, and only 0.8 % to the combination of the environment and spatial component of variation. The results are discussed in the light of wood decay, forest management, and landscape fragmentation. 相似文献
125.
Kjell Saatvedt Harald Lindberg Svein Michelsen Thore Pedersen Egil Seem Odd Geiran 《Cytokine》1996,8(12):944-948
The release of cytokines during cardiopulmonary bypass (CPB) may contribute to haemodynamic alternations encountered after open heart surgery. Regulatory mechanisms exist and include soluble cytokine receptors. We have measured blood levels of tumour necrosis factor (TNF) and its soluble receptor (TNFsr) during and after open heart surgery in children. Correlation analysis to haemodynamic and clinical variables was performed.Using immunoassays the authors registered a significant increase in plasma levels of TNFsr with peak levels 2 h post?operatively at a level of 1702 ± 170 pg/ml. The concentration of TNFsr remained significantly elevated until 48 h postoperatively but TNF was not significantly elevated.An inverse correlation existed between peak TNFsr and mean arterial pressure (rho = −0.827,P< 0.05), between TNFsr and cardiac index (rho = −0.8,P< 0.05), between TNFsr and left ventricular stroke work index (rho = −0.983,P< 0.01), between TNFsr and weight (rho = −0.85,P< 0.05) and between TNFsr and body surface area (rho = −0.867,P< 0.05).The authors demonstrate that the smallest children experienced the highest TNFsr concentration post-operatively. Furthermore cardiac performance, expressed as cardiac index and left ventricular stroke work index, correlated inversely to peak TNFsr level post-operatively. 相似文献
126.
A new [7.0]-metacyclophane has been isolated from the root bark of Myrica nagi. On the basis of spectroscopy the constitution of the new compound is proposed to be 13-oxomyricanol.A new [7.0]-metacyclophane has been isolated from the root bark of Myrica nagi. On the basis of spectroscopy the constitution of the new compound is proposed to be 13-oxomyricanol. 相似文献
127.
Justin J. Meager Anders Fernö Jon Egil Skjæraasen 《Reviews in Fish Biology and Fisheries》2018,28(1):153-176
Cod (Gadus morhua) are an iconic fish species of cultural, historical and economical significance across the Atlantic and adjacent seas. Among many scholarly investigations, this interest has prompted behavioural research, rendering cod one of the few commercially harvested marine fishes for which behaviour has been studied in a comprehensive manner. In our review of this behavioural work, we examine the variability in cod behaviour across five functional domains: foraging, predation, social interactions, migration and reproduction. Research to date suggests a high level of behavioural sophistication in cod that is underpinned by complex learning strategies and long-term memory. Cod also demonstrate substantial variability in how they respond to different ecological circumstances. Considerable variation is evident both within and between individuals, and in some instances, between populations. There are a number of pathways from which this variation appears to arise, such as asocial and social learning, environmental control of phenotypic plasticity and genetic control, but there are no known examples of behaviours that are purely the result of one of these mechanisms. Behavioural variation is therefore likely to result from a combination of these factors, underscoring the need for a quantitative, multivariate approach to understand behavioural variation in cod. 相似文献
128.
A woman with familial plasma lecithin: cholesterol acyltransferase (L.C.A.T.) deficiency showed, like the other reported cases, obvious corneal opacity, proteinuria, and moderate anaemia with a slight haemolytic component. In the plasma the concentrations of free cholesterol, triglycerides, and lecithin were high, and those of esterified cholesterol, lysolecithin, and alphalipoprotein were low. L.C.A.T. activity in plasma was 10% of normal. The heparin-induced lipolytic activity in plasma was reduced. The erythrocyte lipid pattern was abnormal and showed the same pattern as earlier described in L.C.A.T. deficiency.The patient''s brother also probably suffered from the disease and died in uraemia. These are the fourth and fifth known patients with L.C.A.T. deficiency, the first one reported in a male, and the first one with a fatal outcome. 相似文献
129.
Ottem KF Nylund A Karlsbakk E Friis-Møller A Krossøy B 《Archives of microbiology》2007,187(5):343-350
A Francisella sp., isolate GM2212T, previously isolated from diseased farmed Atlantic cod Gadus morhua in Norway is characterized. The complete 16S rDNA, 16S–23S intergenic spacer, 23S rDNA, 23S–5S intergenic spacer, 5S rDNA,
FopA, lipoprotein TUL4 (LpnA), malate dehydrogenase and a hypothetical lipoprotein (LpnB) is sequenced and compared with Francisella tularensis and Francisella philomiragia. All these sequences support a close relationship between GM2212T and F. philomiragia. The bacterium grows at 10–25°C with an optimum at about 20°C, a temperature range clearly different from F. tularensis and F. philomiragia. GM2212T is catalase-positive, indole positive, oxidase-negative, do not produce H2S in Triple Sugar Iron agar, and does not hydrolyze gelatin, is resistant to erythromycin and susceptible to ceftazidime,
the latter five characteristics separating it from F. philomiragia. Cysteine enhances growth. Acid is produced from d-glucose, maltose, sucrose (weak) but not from lactose or glycerol. GM2212T grows on both MacConkey agar and in nutrient broth (6% NaCl). The bacterium is resistant to trimethoprim-sulfamethoxazole,
penicillines, cefuroxime and erythromycin; but is susceptible to ceftazidime, tetracycline, gentamicin, ciprofloxacin. Based
on the molecular and phenotypical characteristics, we suggest that this GM2212 isolate, may represent a new species of Francisella. Isolate GM2212T (=CNCM I-3481T = CNCM I-3511T = DSM 18777T). 相似文献
130.
Autophagy is an evolutionarily conserved lysosomal degradation route for soluble components of the cytosol and organelles.
There is great interest in identifying compounds that modulate autophagy because they may have applications in the treatment
of major diseases including cancer and neurodegenerative disease. Hundeshagen and colleagues describe this month in BMC Biology a screening assay based on flow cytometry that makes it possible to track distinct steps in the autophagic process and thereby
identify novel modulators of autophagy. 相似文献