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81.
82.
The dried rhizomes of Veratrum album were individually extracted with CHCl3, acetone, and NH4OH/benzene to test the toxic effects against the Colorado potato beetle, Leptinotarsa decemlineata, which is an important agricultural pest. Fifteen compounds in various amounts were isolated from the extracts using column and thin‐layer chromatography. The chemical structures of 14 compounds were characterized as octacosan‐1‐ol ( 1 ), β‐sitosterol ( 2 ), stearic acid ( 3 ), diosgenin ( 4 ), resveratrol ( 5 ), wittifuran X ( 6 ), oxyresveratrol ( 7 ), β‐sitosterol 3‐Oβ‐D ‐glucopyranoside ( 8 ), diosgenin 3‐Oα‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyronoside ( 9 ), oxyresveratrol 3‐Oβ‐D ‐glucopyranoside ( 10 ), jervine ( 11 ), pseudojervine ( 13 ), 5,6‐dihydro‐1‐hydroxyjervine ( 14 ), and saccharose ( 15 ) using UV, IR, MS, 1H‐ and 13C‐NMR, and 2D‐NMR spectroscopic methods. However, the chemical structure of 12 , an oligosaccharide, has not fully been elucidated. Compounds 4, 6, 9 , and 10 were isolated from V. album rhizomes for the first time in the current study. The toxic effects of three extracts (acetone, CHCl3, and NH4OH/benzene) and six metabolites, 2, 2 + 4, 5, 7, 8 , and 11 , were evaluated against the Colorado potato beetle. The assay revealed that all three extracts, and compounds 7, 8 , and 11 exhibited potent toxic effects against this pest. This is the first report on the evaluation of the toxic effects of the extracts and secondary metabolites of V. album rhizomes against L. decemlineata. Based on these results, it can be concluded that the extracts can be used as natural insecticides.  相似文献   
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Temperate and boreal forests undergo drastic functional changes in the springtime, shifting within a few weeks from net carbon (C) sources to net C sinks. Most of these changes are mediated by temperature. The autumn 2006–winter 2007 record warm period was followed by an exceptionally warm spring in Europe, making spring 2007 a good candidate for advances in the onset of the photosynthetically active period. An analysis of a decade of eddy covariance data from six European forests stands, which encompass a wide range of functional types (broadleaf evergreen, broadleaf deciduous, needleleaf evergreen) and a wide latitudinal band (from 44° to 62°N), revealed exceptional fluxes during spring 2007. Gross primary productivity (GPP) of spring 2007 was the maximum recorded in the decade examined for all sites but a Mediterranean evergreen forest (with a +40 to +130 gC m?2 anomaly compared with the decadal mean over the January–May period). Total ecosystem respiration (TER) was also promoted during spring 2007, though less anomalous than GPP (with a +17 to +93 gC m?2 anomaly over 5 months), leading to higher net uptake than the long‐term mean at all sites (+12 to +79 gC m?2 anomaly over 5 months). A correlative analysis relating springtime C fluxes to simple phenological indices suggested spring C uptake and temperatures to be related. The CASTANEA process‐based model was used to disentangle the seasonality of climatic drivers (incoming radiation, air and soil temperatures) and biological drivers (canopy dynamics, thermal acclimation of photosynthesis to low temperatures) on spring C fluxes along the latitudinal gradient. A sensitivity analysis of model simulations evidenced the roles of (i) an exceptional early budburst combined with elevated air temperature in deciduous sites, and (ii) an early relief of winter thermal acclimation in coniferous sites for the promotion of 2007 spring assimilation.  相似文献   
85.
Hritcu  Lucian  Bagci  Eyup  Aydin  Emel  Mihasan  Marius 《Neurochemical research》2015,40(9):1799-1809
Neurochemical Research - Ferulago angulata (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains,...  相似文献   
86.
S Aydin  MN Eren  S Aydin  IH Ozercan  AF Dagli 《Peptides》2012,37(2):233-239
This study aimed to examine the effects of CPB on salusin-α, salusin-β and apelin-36 bioactive peptides in people who are planned to undergo coronary artery bypass graft (CABG) operation due to coronary artery disease and to explore whether these peptides are produced in human aortic, saphenous and arterial tissues. The study included age and BMI matched 15 patients who underwent CABG operation by CPB. In order to determine salusin-α, salusin-β and apelin-36 levels, venous blood samples were collected before induction of anesthesia (T1), before CPB (T2), 5min before the removal of cross-clamp (T3), 5min after the removal of cross-clamp (T4), upon arrival in the intensive care (T5), at postoperative 24th hour (T6) and 72nd hour (T7). Salusin and apelin expressions of the tissues were shown by immunohistochemical method. Peptide amounts of sera and tissues were measured using ELISA. Salusins production by vessels occurs in fibroblast cells of the media in the aorta and smooth muscle cells of the media in the LIMA and saphena. Apelin is produced by endothelial cells of the intima and fibroblast cells of the media in the aorta and by smooth muscle cells of the media in the LIMA and saphena. Changes in the levels of salusin-β and apelin-36 were significant during CPB. Salusin-α, salusin-β and apelin-36 are locally synthesized in the arteries and veins. Salusins and apelin-36 might be important markers in the CPB, and also that salusin-β was more specific in comparison to salusin-α.  相似文献   
87.
Conjugated linoleic acid (CLA) has attracted as novel type of fatty acids having unusual health-promoting properties such as anticarcinogenic and antiobesitic effects. The present work employed castor oil as substrate for one-pot production of CLA using washed cells of Lactobacillus plantarum (L. plantarum) and lipases as catalysts. Among the screened lipases, the lipase Rhizopus oryzae (ROL) greatly assisted resting cells to produce CLA. Mass spectral analysis of the product showed that two major isomers of CLA were produced in the reaction mixture i.e. cis-9, trans-11 56.55% and trans-10, cis-12 43.45%. Optimum factors for CLA synthesis were found as substrate concentration (8 mg/mL), pH (6.5), washed cell concentration (12% w/v), and incubation time of 20 h. Hence, the combination of ROL with L. plantarum offers one pot production of CLA selectively using castor oil as a cost-effective substrate.  相似文献   
88.
Evolutionary conservation of protein interaction properties has been shown to be a valuable indication for functional importance. Here we use homology interface modeling of 10 Ras-effector complexes by selecting ortholog proteins from 12 organisms representing the major eukaryotic branches, except plants. We find that with increasing divergence time the sequence similarity decreases with respect to the human protein, but the affinities and association rate constants are conserved as predicted by the protein design algorithm, FoldX. In parallel we have done computer simulations on a minimal network based on Ras-effector interactions, and our results indicate that in the absence of negative feedback, changes in kinetics that result in similar binding constants have strong consequences on network behavior. This, together with the previous results, suggests an important biological role, not only for equilibrium binding constants but also for kinetics in signaling processes involving Ras-effector interactions. Our findings are important to take into consideration in system biology approaches and simulations of biological networks.  相似文献   
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Ghrelin and obestatin are a single gene products and are a multiple functional peptides that regulates energy homeostasis, and food intake. In the present work, we studied the secretion of ghrelin and its co-secreted peptide obestatin in 44 patients with ischemic heart disease with that of 27 healthy matched controls. Here we first conducted using an immunohistochemistry assay to screen whether human salivary glands have any obestatin immunoreactivity. Then, serum and saliva obestatin and acylated ghrelin levels were determined by using Radioimmunoassay. Our immunohistochemical analysis demonstrated that obestatin was localized in the striated and excretory duct of human salivary gland. We also report for the first time that obestatin, like ghrelin, is present in human salivary gland and saliva. No evidence of the role of obestatin or ghrelin saliva levels in the context of ischemic heart disease was found. Salivary ghrelin and obestatin levels are correlated in controls with the blood levels. Determination of salivary values could represent a non-invasive alternative to serum ones that can be useful in clinical practice.  相似文献   
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