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31.
Craig Jamieson Robert A. Campbell Iain A. Cumming Kevin J. Gillen Jonathan Gillespie Bert Kazemier Michael Kiczun Yvonne Lamont Amanda J. Lyons John K.F. Maclean Frederic Martin Elizabeth M. Moir John A. Morrow John Pantling Zoran Rankovic Lynn Smith 《Bioorganic & medicinal chemistry letters》2010,20(20):6072-6075
Starting from lead compound 1, we demonstrate how X-ray structural data can be used to understand SAR and expediently optimize bioavailability in a novel series of AMPA receptor modulators, furnishing 5 with improved bioavailability and robust in vivo activity. 相似文献
32.
Senka S. Vidović Ibrahim O. Mujić Zoran P. Zeković Žika D. Lepojević Vesna T. Tumbas Aida I. Mujić 《Food biophysics》2010,5(1):49-58
Considering the growing interest for mushrooms and the demand search of natural antioxidants sources, the aim of this study
was to investigate the antioxidant properties of two edible widely used Boletus species, Boletus edulis, and Boletus auranticus, collected from Istra region in Croatia in late summer 2007. To evaluate the antioxidant properties and content of antioxidant
compounds, scavenging capacity on DPPH˙, OH˙, and O2˙− radicals, reducing power and capacity to inhibit lipid peroxidation has been investigated. It is determined that content
of total phenols (41.82 ± 0.08 mg gallic acid equivalent per gram of dry extract) was higher for B. edulis. Using high performance liquid chromatography/diode array detector analysis, the main antioxidant compound, variegatic acid,
has been detected and quantified. 1,1-Diphenyl-2-picryl-hydrazyl-hydrate assay was used as a preliminary free radical–scavenging
evaluation. By this assay, it has been found that B. edulis dry mushroom extract exhibits 50% of inhibition value at the extract concentration of 0.016 ± 0.0003 mg/ml. The extracts
were capable of reducing iron(III) and, thus, are capable of donating electrons. Using electron paramagnetic resonance spin-trapping
and spin-probing techniques, activity against relevant reactive species, ˙OH and O2˙− radical, was analyzed for both mushroom extracts. Both investigated extracts are determined as good inhibitors for ˙OH radical
reduction, and both exhibited significant capacity for scavenging O2˙− radical and for that could help to prevent or meliorate oxidative damage. Only B. edulis extract prevents lipid peroxidation. Investigated mushroom extracts could represent easily accessible natural antioxidant
resource. 相似文献
33.
Vegetative bud dormancy in woody perennial plants of the temperateregions is an important adaptive strategy for withstanding lowwinter temperatures. We used shortday (SD) photoperiods to inducebud dormancy in poplar (Populus deltoides Bartr. ex Marsh.),and characterized changes in protein profiles during dormancydevelopment. Short days alone, under warm temperatures (25°C)induced a high level of dormancy comparable to that developednaturally. Under SD conditions the amounts of acetone/trichloroaceticacid (TCA)-insoluble dry powder (DP) increased in terminal andlateral buds, leaves and bark tissues. The total protein contentin DP from buds and leaves steadily decreased while total proteinfrom bark increased. The 2-dimensional (2-D) PAGE analyses showedthat terminal and lateral buds responded similarly to SD. Fourpolypeptides that newly appeared or increased in abundance andfive that disappeared or diminished in terminal buds during10 weeks of treatment were also detected in lateral buds. Twoof these newly apparent polypeptides were also found in bark.Similar polypeptides were not found in leaves. Changes in proteinmetabolism and possibly altered gene expression might be importantpart in the overall response of poplar to SD during dormancydevelopment.
This is Oregon Agricultural Experimental Station Technical PaperNumber 1122. 相似文献
34.
The reaction-diffusion system of the neuromuscular junction has been modeled in 3D using the finite element package FEtk. The numerical solution of the dynamics of acetylcholine with the detailed reaction processes of acetylcholinesterases and nicotinic acetylcholine receptors has been discussed with the reaction-determined boundary conditions. The simulation results describe the detailed acetylcholine hydrolysis process, and reveal the time-dependent interconversion of the closed and open states of the acetylcholine receptors as well as the percentages of unliganded/monoliganded/diliganded states during the neuro-transmission. The finite element method has demonstrated its flexibility and robustness in modeling large biological systems. 相似文献
35.
The aim of the study was to determine a combination of anthropometric variables that would enable better differentiation between benign and malignant ovarian masses. Prospective study has been performed in a two year period in which 208 women with ovarian lesions were analyzed and correlated with histopathologic surgical findings. We examined the relation between self-reported anthropometric and other variables (height, weight, body mass index--BMI, parity, marital status, education, age, rural versus urban residence, menopausal status) and incidence of ovarian cancer. Age, parity, marital status and menopausal status individually showed statistical significance. 相似文献
36.
Persec J Persec Z Buković D Husedzinović I Buković N Pavelić L 《Collegium antropologicum》2007,31(4):1071-1075
Preemptive analgesia refers to blockade of afferent nerve fibers before a painful stimulus, which prevents or reduces subsequent pain even beyond the effect of the block. The aim of the study was to compare the effect of clonidine used before and at the end of operation on pain control in abdominal surgery. A total of 77 patients admitted for colorectal surgery were randomly classified into three groups: epidural clonidine before operation, epidural clonidine at the end of operation, and control group. After the operation on patient demand, analgesia with boluses of epidural morphine was instituted. The parameters of postoperative pain level using VAS score (visual analog scale), sedation and analgesics consumption were determined as outcome measures at 1, 2, 6, and 24 h of the operation. Clonidine administered before operation provided lowest pain scores at 6 and 24 h (p < 0.05). Clonidine administered at the end of operation had low pain scores at 1 and 2 h, with a significant pain breakthrough thereafter (6.93 +/- 1.66 at 6 h and 4.04 +/- 2.39 at 24 h) compared with the group administered clonidine before operation (3.60 +/- 2.94 and 3.71 +/- 1.82). Clonidine administered before operation provided less sedation (p < 0.05) and a significantly lower use of analgesics (p < 0.05). Blockade of nociceptive stimulus using the centrally acting alpha2-adrenergic agonist clonidine before the onset of pain stimulus resulted in reduced pain levels, sedation and analgesic requirement. 相似文献
37.
Brassinin is a plant defense metabolite with antimicrobial activity produced de novo by a variety of Brassica species in response to stress, that is, a phytoalexin. The inhibition of brassinin oxidase (BO), a brassinin-detoxifying enzyme produced by the phytopathogenic fungus Leptosphaeria maculans, is a target in our continuing search for novel crop protection agents. To probe the substrate specificity of BO, in particular the mechanism of the detoxification step, several analogues of brassinin, including functional group isosteres ((mono/dithio)carbamate, urea, and thiourea) and homologue methyl tryptaminedithiocarbamate, were investigated using fungal cultures and purified BO. It was concluded that the essential structural features of substrates of BO were: (i) an -NH at the (mono/dithio)carbamate, urea or thiourea group; (ii) a methylene bridge between indole and the functional group; (iii) a methyl or ethyl group attached to the thiol moiety of the (mono/di)thiocarbamate group. A general stepwise pathway for the oxidation of brassinin was proposed that accounts for the structural requirements of detoxification of brassinin analogues in L. maculans. All compounds that were BO substrates appeared to be oxidized in mycelial cultures to aldehydes, except for the two most polar compounds N'-(3-indolylmethyl)-N'-methylurea and methyl N'-(3-indolylmethyl)carbamate. The substrate specificity of BO suggests that selective inhibitors can be designed for the potential control of L. maculans. 相似文献
38.
Weiwei Wen Kun Li Saleh Alseekh Nooshin Omranian Lijun Zhao Yang Zhou Yingjie Xiao Min Jin Ning Yang Haijun Liu Alexandra Florian Wenqiang Li Qingchun Pan Zoran Nikoloski Jianbing Yan Alisdair R. Fernie 《The Plant cell》2015,27(7):1839-1856
Deciphering the influence of genetics on primary metabolism in plants will provide insights useful for genetic improvement and enhance our fundamental understanding of plant growth and development. Although maize (Zea mays) is a major crop for food and feed worldwide, the genetic architecture of its primary metabolism is largely unknown. Here, we use high-density linkage mapping to dissect large-scale metabolic traits measured in three different tissues (leaf at seedling stage, leaf at reproductive stage, and kernel at 15 d after pollination [DAP]) of a maize recombinant inbred line population. We identify 297 quantitative trait loci (QTLs) with moderate (86.2% of the mapped QTL, R2 = 2.4 to 15%) to major effects (13.8% of the mapped QTL, R2 >15%) for 79 primary metabolites across three tissues. Pairwise epistatic interactions between these identified loci are detected for more than 25.9% metabolites explaining 6.6% of the phenotypic variance on average (ranging between 1.7 and 16.6%), which implies that epistasis may play an important role for some metabolites. Key candidate genes are highlighted and mapped to carbohydrate metabolism, the tricarboxylic acid cycle, and several important amino acid biosynthetic and catabolic pathways, with two of them being further validated using candidate gene association and expression profiling analysis. Our results reveal a metabolite-metabolite-agronomic trait network that, together with the genetic determinants of maize primary metabolism identified herein, promotes efficient utilization of metabolites in maize improvement. 相似文献
39.
Jamieson C Maclean JK Brown CI Campbell RA Gillen KJ Gillespie J Kazemier B Kiczun M Lamont Y Lyons AJ Moir EM Morrow JA Pantling J Rankovic Z Smith L 《Bioorganic & medicinal chemistry letters》2011,21(2):805-811
Starting from compound 1, we utilized biostructural data to successfully evolve an existing series into a new chemotype with a promising overall profile, exemplified by 19. 相似文献
40.
Girirajan S Brkanac Z Coe BP Baker C Vives L Vu TH Shafer N Bernier R Ferrero GB Silengo M Warren ST Moreno CS Fichera M Romano C Raskind WH Eichler EE 《PLoS genetics》2011,7(11):e1002334
While numerous studies have implicated copy number variants (CNVs) in a range of neurological phenotypes, the impact relative to disease severity has been difficult to ascertain due to small sample sizes, lack of phenotypic details, and heterogeneity in platforms used for discovery. Using a customized microarray enriched for genomic hotspots, we assayed for large CNVs among 1,227 individuals with various neurological deficits including dyslexia (376), sporadic autism (350), and intellectual disability (ID) (501), as well as 337 controls. We show that the frequency of large CNVs (>1 Mbp) is significantly greater for ID-associated phenotypes compared to autism (p = 9.58 × 10(-11), odds ratio = 4.59), dyslexia (p = 3.81 × 10(-18), odds ratio = 14.45), or controls (p = 2.75 × 10(-17), odds ratio = 13.71). There is a striking difference in the frequency of rare CNVs (>50 kbp) in autism (10%, p = 2.4 × 10(-6), odds ratio = 6) or ID (16%, p = 3.55 × 10(-12), odds ratio = 10) compared to dyslexia (2%) with essentially no difference in large CNV burden among dyslexia patients compared to controls. Rare CNVs were more likely to arise de novo (64%) in ID when compared to autism (40%) or dyslexia (0%). We observed a significantly increased large CNV burden in individuals with ID and multiple congenital anomalies (MCA) compared to ID alone (p = 0.001, odds ratio = 2.54). Our data suggest that large CNV burden positively correlates with the severity of childhood disability: ID with MCA being most severely affected and dyslexics being indistinguishable from controls. When autism without ID was considered separately, the increase in CNV burden was modest compared to controls (p = 0.07, odds ratio = 2.33). 相似文献