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41.
Chemical Composition of Ballota macedonica Vandas and Ballota nigra L. ssp. foetida (Vis.) Hayek Essential Oils – The Chemotaxonomic Approach 下载免费PDF全文
Aleksandra S. Đorđević Olga P. Jovanović Bojan K. Zlatković Gordana S. Stojanović 《化学与生物多样性》2016,13(6):782-788
The essential oils isolated from fresh aerial parts of Ballota macedonica (two populations) and Ballota nigra ssp. foetida were analyzed by GC and GC/MS. Eighty five components were identified in total; 60 components in B. macedonica oil (population from the Former Yugoslav Republic of Macedonia), 34 components in B. macedonica oil (population from the Republic of Serbia), and 33 components in the oil of B. nigra ssp. foetida accounting for 93.9%, 98.4%, and 95.8% of the total oils, respectively. The most abundant components in B. macedonica oils were carotol (13.7 – 52.1%), germacrene D (8.6 – 24.6%), and (E)‐caryophyllene (6.5 – 16.5%), while B. nigra ssp. foetida oil was dominated by (E)‐phytol (56.9%), germacrene D (10.0%), and (E)‐caryophyllene (4.7%). Multivariate statistical analyses (agglomerative hierarchical cluster analysis and principal component analysis) were used to compare and discuss relationships among Ballota species examined so far based on their volatile profiles. The chemical compositions of B. macedonica essential oils are reported for the first time. 相似文献
42.
Mark Pennington Aleksandra Gentry-Maharaj Chloe Karpinskyj Alec Miners Julie Taylor Ranjit Manchanda Rema Iyer Michelle Griffin Andy Ryan Ian Jacobs Usha Menon Rosa Legood 《PloS one》2016,11(11)
BackgroundThere is limited evidence on the costs of Endometrial Cancer (EC) by stage of disease. We estimated the long-term secondary care costs of EC according to stage at diagnosis in an English population-based cohort.MethodsWomen participating in UKCTOCS and diagnosed with EC following enrolment (2001–2005) and prior to 31st Dec 2009 were identified to have EC through multiple sources. Survival was calculated through data linkage to death registry. Costs estimates were derived from hospital records accessed from Hospital Episode Statistics (HES) with additional patient level covariates derived from case notes and patient questionnaires. Missing and censored data was imputed using Multiple Imputation. Regression analysis of cost and survival was undertaken.Results491 of 641 women with EC were included. Five year total costs were strongly dependent on stage, ranging from £9,475 (diagnosis at stage IA/IB) to £26,080 (diagnosis at stage III). Stage, grade and BMI were the strongest predictors of costs. The majority of costs for stage I/II EC were incurred in the first six months after diagnosis while for stage III / IV considerable costs accrued after the first six months.ConclusionsIn addition to survival advantages, there are significant cost savings if patients with EC are detected earlier. 相似文献
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Metodi?D. Metodiev Kyle Thompson Charlotte?L. Alston Andrew?A.M. Morris Langping He Zarah Assouline Marlène Rio Nadia Bahi-Buisson Angela Pyle Helen Griffin Stefan Siira Aleksandra Filipovska Arnold Munnich Patrick?F. Chinnery Robert McFarland Agnès R?tig Robert?W. Taylor 《American journal of human genetics》2016,99(1):246
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Aleksandra Eckstein Weronika Krzeszowiec Piotr Waligórski Halina Gabryś 《Physiologia plantarum》2016,156(3):351-366
Auxin is involved in a wide spectrum of physiological processes in plants, including responses controlled by the blue light photoreceptors phototropins: phototropic bending and stomatal movement. However, the role of auxin in phototropin‐mediated chloroplast movements has never been studied. To address this question we searched for potential interactions between auxin and the chloroplast movement signaling pathway using different experimental approaches and two model plants, Arabidopsis thaliana and Nicotiana tabacum. We observed that the disturbance of auxin homeostasis by shoot decapitation caused a decrease in chloroplast movement parameters, which could be rescued by exogenous auxin application. In several cases, the impairment of polar auxin transport, by chemical inhibitors or in auxin carrier mutants, had a similar negative effect on chloroplast movements. This inhibition was not correlated with changes in auxin levels. Chloroplast relocations were also affected by the antiauxin p‐chlorophenoxyisobutyric acid and mutations in genes encoding some of the elements of the SCFTIR1‐Aux/IAA auxin receptor complex. The observed changes in chloroplast movement parameters are not prominent, which points to a modulatory role of auxin in this process. Taken together, the obtained results suggest that auxin acts indirectly to regulate chloroplast movements, presumably by regulating gene expression via the SCFTIR1‐Aux/IAA‐ARF pathway. Auxin does not seem to be involved in controlling the expression of phototropins. 相似文献
47.
Main conclusion
Coleoptera, the largest and the most diverse Insecta order, is characterized by multiple adaptations to plant feeding. Insect-associated microorganisms can be important mediators and modulators of interactions between insects and plants. Interactions between plants and insects are highly complex and involve multiple factors. There are various defense mechanisms initiated by plants upon attack by herbivorous insects, including the development of morphological structures and the synthesis of toxic secondary metabolites and volatiles. In turn, herbivores have adapted to feeding on plants and further sophisticated adaptations to overcome plant responses may continue to evolve. Herbivorous insects may detoxify toxic phytocompounds, sequester poisonous plant factors, and alter their own overall gene expression pattern. Moreover, insects are associated with microbes, which not only considerably affect insects, but can also modify plant defense responses to the benefit of their host. Plants are also frequently associated with endophytes, which may act as bioinsecticides. Therefore, it is very important to consider the factors influencing the interaction between plants and insects. Herbivorous insects cause considerable damage to global crop production. Coleoptera is the largest and the most diverse order in the class Insecta. In this review, various aspects of the interactions among insects, microbes, and plants are described with a focus on coleopteran species, their bacterial symbionts, and their plant hosts to demonstrate that many factors contribute to the success of coleopteran herbivory.48.
HD2C histone deacetylase and a SWI/SNF chromatin remodelling complex interact and both are involved in mediating the heat stress response in Arabidopsis 下载免费PDF全文
49.
Loss of CLPP alleviates mitochondrial cardiomyopathy without affecting the mammalian UPRmt 下载免费PDF全文
Dominic Seiferling Karolina Szczepanowska Christina Becker Katharina Senft Steffen Hermans Priyanka Maiti Tim König Alexandra Kukat Aleksandra Trifunovic 《EMBO reports》2016,17(7):953-964
The mitochondrial matrix protease CLPP plays a central role in the activation of the mitochondrial unfolded protein response (UPRmt) in Caenorhabditis elegans. Far less is known about mammalian UPRmt signaling, although similar roles were assumed for central players, including CLPP. To better understand the mammalian UPRmt signaling, we deleted CLPP in hearts of DARS2‐deficient animals that show robust induction of UPRmt due to strong dysregulation of mitochondrial translation. Remarkably, our results clearly show that mammalian CLPP is neither required for, nor it regulates the UPRmt in mammals. Surprisingly, we demonstrate that a strong mitochondrial cardiomyopathy and diminished respiration due to DARS2 deficiency can be alleviated by the loss of CLPP, leading to an increased de novo synthesis of individual OXPHOS subunits. These results question our current understanding of the UPRmt signaling in mammals, while introducing CLPP as a possible novel target for therapeutic intervention in mitochondrial diseases. 相似文献
50.
Aleksandra Kładna Paweł Berczyński Irena Kruk Teresa Piechowska Hassan Y. Aboul‐Enein 《Luminescence》2016,31(6):1201-1206
Isoflavones genistein and daidzein are nonsteroidal phytoestrogens occurring mainly in soybean foods. These phytoestrogens possess estrogenic properties and show a variety of health benefits as anti‐inflammatory agents. However, the mechanism of their action has not been identified in detail. The aim of this study is to characterize the antioxidant powers of genistein, daidzein and daidzein metabolite–equol through their activities to scavenge superoxide anion radical (O?2?), hydroxyl radical (HO?), 2,2–diphenyl–1‐picrylhydrazyl radical (DPPH?) and hydrogen peroxide (H2O2) using chemiluminescence and spectrophotometry techniques. Potassium superoxide in dimethyl sulphoxide (DMSO) and 18‐crown‐6 ether were used as a source of O?2?. Hydroxyl radicals were produced using the Fenton reaction. In free radical assays, genistein had the IC50 values (an amount of antioxidant concentration required to decrease the initial radical concentration by 50%) 0.391 ± 0.012 mM for O?2?, 0.621 ± 0.028 mM for HO? and 1.89 ± 0.16 mM for DPPH?. The IC50 values for daidzein for these free radicals were 1.924 ± 0.011 mM, 0.702 ± 0.012 mM and 2.81 ± 0.03 mM, respectively. Equol was the most active the free radical scavenger with IC50 = 0.451 ± 0.018 mM for HO? and IC50 = 1.36 ± 0.11 mM for DPPH?. All tested compounds exerted a significant effect on the H2O2: IC50 = 18.1 ± 1.1 μM for genistein, IC50 = 2.1 ± 0.5 μM for daidzein, and IC50 = 1.06 ± 0.2 μM for equol. These findings show that genistein, daidzein and equol are effective free radical scavengers and possess high antioxidant power in vitro. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献