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51.
Fereshteh Khorrami Oruj Valizadegan Maryam Forouzan Asmar Soleymanzade 《Archives Of Phytopathology And Plant Protection》2013,46(13-14):685-695
AbstractRed flour beetle, Tribolium castaneum Herbst (Coleoptera: Tenebrionidae) is a prominent pest of stored products particularly cereal flour. Since resistance of this pest to common chemical insecticides is well documented, we were examined the synergistic/antagonistic interaction between Satureja hortensis L., Trachyspermum ammi L., Ziziphora tenuior L., Cuminum cyminum L. and Foeniculum vulgare Miller essential oils, ethanolic extracts and powders with Diatomaceous earth (DE) against T. castaneum adults under laboratory conditions at 27 ± 1 °C, 65 ± 5% RH and continuous darkness. We assayed repellency of ethanolic extracts and essential oils of mentioned plants on the pest. Results showed that DE had high toxicity to the pest. Plant essential oils and ethanolic extracts (except ziziphora) synergized the performance of DE. Nevertheless, plant powders elicited antagonistic effects (except ziziphora that exhibited synergistic effect). The most repellent EO and extract was cumin which exhibited mean repellency value on adult insect equivalent to 92.58 and 51.47%, respectively. 相似文献
52.
Raitis Peculis Ilze Konrade Elina Skapare Davids Fridmanis Liene Nikitina-Zake Aivars Lejnieks Valdis Pirags Maija Dambrova Janis Klovins 《Gene》2013
The glyoxalase system and its main enzyme, glyoxalase 1 (GLO1), protect cells from advanced glycation end products (AGEs), such as methylglyoxal (MG) and other reactive dicarbonyls, the formation of which is increased in diabetes patients as a result of excessive glycolysis. MG is partly responsible for harmful protein alterations in living cells, notably in neurons, leading to their dysfunction, and recent studies have shown a negative correlation between GLO1 expression and tissue damage. Neuronal dysfunction is a common diabetes complication due to elevated blood sugar levels, leading to high levels of AGEs. The aim of our study was to determine whether single nucleotide polymorphisms (SNPs) in the GLO1 gene influence activity of the enzyme. In total, 125 healthy controls, 101 type 1 diabetes, and 100 type 2 diabetes patients were genotyped for three common SNPs, rs2736654 (A111E), rs1130534 (G124G), and rs1049346 (5′-UTR), in GLO1. GLO1 activity was determined in whole blood lysates for all participants of the study. 相似文献
53.
Weidong He Luc Van Puyvelde Jan Bosselaers Norbert De Kimpe Marc Van Der Flaas Annemie Roymans 《Biofouling》2013,29(3):221-226
A screening of antifouling activity from plants extracts led to selection and further study of Maesa lanceolata Forssk. Two p‐benzoquinone compounds were isolated from the fruits and found to be active against Artemia salina. The anti‐crustacean activity of both p‐benzoquinones is reported for the first time. 相似文献
54.
Faizul Azam Honiwa Suliman Abodabos Ismail M. Taban Abdalla R. Rfieda Danish Mahmood Md Jamir Anwar 《Molecular simulation》2013,39(18):1563-1571
ABSTRACTInhibitors of monoamine oxidase (MAO)-B have been used for many years in the therapy of Parkinson’s disease (PD). Owing to the safety concerns of the currently used agents, the discovery of novel scaffolds is of considerable interest. MAO-B inhibitory potential of rutin, a flavonoid derived from natural sources, has been established in experimental findings. Hence, the current study seeks to examine the interactions between rutin and crystal structure of human MAO-B enzyme. Molecular docking calculations, as well as molecular dynamics simulations, were employed to investigate the binding mode and the stability of the rutin/MAO-B complex. Energies of highest occupied/lowest unoccupied molecular orbitals were computed through DFT studies and used to calculate electron affinity, hardness, chemical potential, electronegativity, and electrophilicity index in order to investigate the capability of these parameters to influence the ligand–receptor interactions. It was found that rutin traverses both the entrance cavity and the substrate cavity, forcing the Ile-199 ‘gate’ to rotate into its open conformation. It results in the fusion of the two cavities of the MAO-B binding site and directly leads to better binding interactions. Results of the current study can be used for lead modification and development of novel drugs for the treatment of PD. 相似文献
55.
DSP is an important by-product of alumina production via the Bayer process. Under Western Australian processing conditions, the DSP has a sodalite-type structure that can incorporate anions within its framework. This is particularly useful for removal of impurity anions from liquor recycled in the circuit. As a first step to gaining a fundamental understanding of the incorporation process, we have undertaken molecular mechanics calculations to examine the interaction energy between a series of anions and the sodalite framework, as a measure of the affinity of the anions for the sodalite cage. Our calculations predict that the ions have an increased affinity for the cage along the series aluminate, chloride, carbonate, sulfate and hydroxide. These calculations have successfully predicted the trends that we observe from competitive-uptake experiments in our laboratory. 相似文献
56.
《Chronobiology international》2013,30(4):765-783
The objective of this study was to determine systolic, diastolic, and mean arterial blood pressure (SBP, DBP, and MAP), heart rate (HR), double-product (DP: SBP×HR), and activity levels and their 24h pattern in liver glycogen storage disease (LGSD) patients. A case series of 12 (11 pediatric and one adult) diurnally active LGSD (seven type I, three type III, and two type IX) subjects were simultaneously assessed by 24h ambulatory blood pressure monitoring and wrist actigraphy. Nine subjects were judged to be hypertensive based on the criterion of an elevated 24h mean SBP and/or DBP being elevated beyond reference standards or the SBP and/or DBP load (percentage of time BP exceeds normal values) being greater than 25%. Two of the three other subjects, not viewed as hypertensive based on their 24h average SBP or DBP, exhibited daytime or nighttime SBP and/or DBP load hypertension. Each study variables displayed statistically significant (p<0.001) group circadian rhythmicity. The SBP, DBP, and MAP displayed comparable 24h patterns of appreciable amplitude (total peak–trough variation equal to 17.7, 23.6, and 19.6%, respectively, of the 24h mean) with highest values (orthophase) occurring ~11 h after the commencement of daytime activity. The sleep-time trough (bathyphase) occurred ~4.5 h before morning awakening. The statistically significant (p<0.006) circadian rhythms of HR (amplitude equal to 33.2% of the 24h mean) and DP (amplitude equal to 49.4% of the 24h mean) peaked earlier, ~7.4 h into the daytime activity span. The sleep-time trough occurred ~3 h before morning awakening. The 24h pattern in the cardiovascular variables was correlated with the 24h pattern of activity, with r ranging from 0.50 for DBP to 0.39 for HR. 相似文献
57.
Roya R.R. Sardari Tarek Dishisha Sang‐Hyun Pyo Rajni Hatti‐Kaul 《Biotechnology and bioengineering》2013,110(4):1243-1248
3‐Hydroxypropionaldehyde (3HPA) is an important specialty chemical which can be produced from glycerol using resting cells of Lactobacillus reuteri. This biocatalytic route, however, suffers from substrate‐ and product‐mediated loss of enzyme activity within 2 h of biotransformation. In order to overcome the inhibitory effects of 3HPA, complex formation with sodium bisulfite was investigated, optimized and applied for in situ capture of the aldehyde during biotransformation of glycerol in a fed‐batch process. As a result, the activity of the cells was maintained for at least 18 h. The 3HPA produced per gram cell dry weight was increased 5.7 times compared to the batch production process, and 2.2 times compared to fed‐batch process without in situ complex formation. This approach may have potential for production and in situ removal of 3HPA after further process development. Biotechnol. Bioeng. 2013; 110: 1243–1248. © 2012 Wiley Periodicals, Inc. 相似文献
58.
Xianwen Cao Jing Jiang Shoude Zhang Lili Zhu Juan Zou Yanyan Diao Weilie Xiao Lei Shan Handong Sun Weidong Zhang Jin Huang Honglin Li 《Bioorganic & medicinal chemistry letters》2013,23(11):3329-3333
Eleven compounds were identified as estrogen receptor modulators from an in-house natural product database (NPD) by structure-based virtual screening for ERα and ERβ. Among them, 3 compounds were confirmed as ER agonists and 8 compounds were confirmed as ER antagonists by yeast two-hybrid (Y2H) assay, with EC50 values ranging from several micromolar to 100 micromolar. In this study, a novel series of cycloartane triterpenoids isolated from Schisandra glaucescens Diels was found to have ER antagonistic effect, the most potent antagonist of which exhibited activity with EC50 value of 2.55 and 4.68 μM for ERα and ERβ, respectively. Moreover, the types of modulation and subtype selectivity were also investigated through molecular docking simulation. 相似文献
59.
Zhenjian Lin Lenny Marett Ronald W. Hughen Malem Flores Imelda Forteza Mary Anne Ammon Gisela P. Concepcion Samuel Espino Baldomero M. Olivera Gary Rosenberg Margo G. Haygood Alan R. Light Eric W. Schmidt 《Bioorganic & medicinal chemistry letters》2013,23(17):4867-4869
The bacterium Gordonia sp. 647 W.R.1a.05 was cultivated from the venom duct of the cone snail, Conus circumcisus. The Gordonia sp. organic extract modulated the action potential of mouse dorsal root ganglion neurons. Assay-guided fractionation led to the identification of the new compound circumcin A (1) and 11 known analogs (2–12). Two of these compounds, kurasoin B (7) and soraphinol A (8), were active in a human norepinephrine transporter assay with Ki values of 2575 and 867 nM, respectively. No neuroactivity had previously been reported for compounds in this structural class. Gordonia species have been reproducibly isolated from four different cone snail species, indicating a consistent association between these organisms. 相似文献
60.
Cassandra L.A. Hawco Estelle Marchal Md. Imam Uddin Alexander E.G. Baker Dale P. Corkery Graham Dellaire Alison Thompson 《Bioorganic & medicinal chemistry》2013,21(19):5995-6002
To generate the first series of prodigiosene conjugates, the tripyrrolic skeleton was appended to estrone, tamoxifen and porphyrin frameworks by way of ester linkers and various hydrocarbon chain lengths. The ability of the conjugates to inhibit various types of cancer cells was evaluated in vitro. The porphyrin conjugates did not exhibit significant activity. The estrone conjugates exhibited modest activity, for the most part. However, significantly greater growth inhibition activity against certain breast, colon, lung, leukemia, melanoma and prostate cell lines was noted. This unusual effect for this first generation model class of compound warrants further investigation and comparison to cases where estrogens are linked to prodigiosenes via connection points that do not feature in estrogen receptor binding. The 4-hydroxytamoxifen conjugates exhibit nanomolar range activity against the MCF-7 breast cancer cell line, paving the way to expand the scope and connectivity of prodigiosene–tamoxifen conjugates. 相似文献