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1.
Raimundo Wagner Souza Aguiar Suetonio Fernandes dos Santos Fabricio da Silva Morgado Sergio Donizeti Ascencio Magnólia de Mendon?a Lopes Kelvinson Fernandes Viana Julcemar Didonet Bergmann Morais Ribeiro 《PloS one》2015,10(2)
This study investigated the toxic effects of essential oils isolated from Siparuna guianensis against Aedes aegypti, Culex quinquefasciatus (eggs, larvae, pupae, and adult) and Aedes albopictus (C6/36) cells. The oviposition-deterring activity, egg viability, and repellence activity in the presence of different essential oils concentrations were determined. The essential oils showed high toxicity to all developmental stages of A. aegypti and C. quinquefasciatus. Furthermore, the oils also showed high repellent activity towards the adult stage of mosquitoes (0.025 to 0.550 μg/cm2 skin conferred 100% repellence up to 120 min) and in contact with cultured insect cells (C6/36) induced death possibly by necrosis. The results presented in this work show the potential of S. guianensis essential oils for the development of an alternative and effective method for the natural control of mosquitoes in homes and urban areas. 相似文献
2.
Adriana R. Aguilar-Melo Sophie Calmé Braulio Pinacho-Guendulain Sandra E. Smith-Aguilar Gabriel Ramos-Fernández 《American journal of primatology》2020,82(1):e23077
Some social species exhibit high levels of fission–fusion dynamics (FFD) that improve foraging efficiency. In this study, we shed light on the way that FFD allows animal groups to cope with fluctuations in fruit availability. We explore the relative contribution of fruit availability and social factors like sex in determining association and proximity patterns in spider monkeys. We tested the influence of fruit availability and social factors on the association and proximity patterns using three-year data from a group of spider monkeys in the Yucatan Peninsula of Mexico. We identified subgroup members and estimated their Interindividual distances through instantaneous scan sampling. We evaluated fruit availability by monitoring the phenology of the 10 most important food tree species for spider monkeys in the study site. Social network analyses allowed us to evaluate association and proximity patterns in subgroups. We showed that association patterns vary between seasons, respond to changes in fruit availability, and are influenced by the sex of individuals, likely reflecting biological and behavioral differences between sexes and the interplay between ecological and social factors. In contrast, proximity patterns were minimally affected by changes in fruit availability, suggesting that social factors are more important than food availability in determining cohesion within subgroups. 相似文献
3.
Two species of DHFR were identified in wild-type L1210 murine leukemia cells by analysis of the kinetics of the binding of MTX and dissociation of the MTX-enzyme complex at pH 5.0 and pH 7.2. The two forms of DHFR were also distinguished by immunoinhibition of the binding of MTX and the catalytic reduction of FH2 to FH4 using an antiserum raised to the purified high affinity form of DHFR. The Ka for the binding of MTX by the low affinity form of the enzyme is 4.5 x 10(7) M-1, substantially lower than the reported Ka for the binding of this drug by the high affinity enzyme. The low affinity form of the enzyme catalyzed the reduction of FH2 to FH4 at a rate slower than the high affinity form of DHFR. 相似文献
4.
Maria Mullins James Den Uyl Emily Cruz Samantha Trail Benjamin Davidson Diane Campbell Emily Mooney 《Ecological Entomology》2020,45(5):1004-1014
1. The abundance of insect herbivores is mediated by interactions with higher and lower trophic levels. This research asks (i) how phenological change across trophic levels affects host plant quality and selection for aphids, and (ii) what higher trophic level mechanisms drive aphid abundance. 2. Ligusticum porteri is a perennial host for the sap-feeding aphid Aphis asclepiadis and intraguild mirid predators (chiefly Lygus hesperus) in Colorado. We used long-term observational data to discover that aphids and mirids respond differently to phenological cues. These unique responses can impact aphid abundance through changes to host plant selection and quality. 3. We used behavioural choice assays to assess how advanced mirid phenology influences aphid host plant selection. More alates landed and reproduced on mirid-free control plants relative to host plants with prior mirid feeding. However, this preference did not correlate with aphid performance when we compared aphid relative growth rates between treatments. This suggests that advanced mirid phenology would impact aphid populations more through host plant choice, rather than reductions in host quality. The addition of mirids to experimental aphid colonies also demonstrated reduced aphid colony growth via predation. 4. We measured plant cues involved in host selection and found differences in volatile composition between plants with prior mirid feeding compared to control plants, providing the potential for aphids to detect enemy-free space using volatile cues. 相似文献
5.
Katherina Walz Devon Cohen Paul M. Neilsen Joseph Foster II. Francesco Brancati Korcan Demir Richard Fisher Michelle Moffat Nienke E. Verbeek Kathrine Bjørgo Adriana Lo Castro Paolo Curatolo Giuseppe Novelli Clemer Abad Cao Lei Lily Zhang Oscar Diaz-Horta Juan I. Young David F. Callen Mustafa Tekin 《Human genetics》2015,134(2):181-190
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7.
Nicéia Spanholi Calgaroto Gustavo Roberto Thomé Pauline da Costa Jucimara Baldissareli Fátima Abdala Hussein Roberta Schmatz Maribel A. Rubin Cristiane Signor Daniela Aymone Ribeiro Fabiano Barbosa Carvalho Lizielle Souza de Oliveira Luciane Belmonte Pereira Vera Maria Morsch Maria Rosa Chitolina Schetinger 《Cell biochemistry and function》2014,32(6):502-510
Diabetes is associated with long‐term complications in the brain and reduced cognitive ability. Vitamin D3 (VD3) appears to be involved in the amelioration of hyperglycaemia in streptozotocin (STZ)‐induced diabetic rats. Our aim was to analyse the potential of VD3 in avoiding brain damage through evaluation of acetylcholinesterase (AChE), Na+K+‐adenosine triphosphatase (ATPase) and delta aminolevulinate dehydratase (δ‐ALA‐D) activities and thiobarbituric acid reactive substance (TBARS) levels from cerebral cortex, as well as memory in STZ‐induced diabetic rats. Animals were divided into eight groups (n = 5): control/saline, control/metformin (Metf), control/VD3, control/Metf + VD3, diabetic/saline, diabetic/Metf, diabetic/VD3 and diabetic/Metf + VD3. Thirty days after treatment, animals were submitted to contextual fear‐conditioning and open‐field behavioural tests, after which they were sacrificed and the cerebral cortex was dissected. Our results demonstrate a significant memory deficit, an increase in AChE activity and TBARS levels and a decrease in δ‐ALA‐D and Na+K+‐ATPase activities in diabetic rats when compared with the controls. Treatment of diabetic rats with Metf and VD3 prevented the increase in AChE activity when compared with the diabetic/saline group. In treated diabetic rats, the decrease in Na+K+‐ATPase was reverted when compared with non‐treated rats, but the increase in δ‐ALA‐D activity was not. VD3 prevented diabetes‐induced TBARS level and improved memory. Our results show that VD3 can avoid cognitive deficit through prevention of changes in important enzymes such as Na+K+‐ATPase and AChE in cerebral cortex in type 1 diabetic rats. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
9.
Camila Simioni Vanzin Caroline Paula Mescka Bruna Donida Tatiane Grazieli Hammerschimidt Graziela S. Ribas Janaína Kolling Emilene B. Scherer Laura Vilarinho Célia Nogueira Adriana Simon Coitinho Moacir Wajner Angela T. S. Wyse Carmen Regla Vargas 《Cellular and molecular neurobiology》2015,35(6):899-911
10.
Xinzhu Deng David Michaelson Jason Tchieu Jin Cheng Diana Rothenstein Regina Feldman Sang-gyu Lee John Fuller Adriana Haimovitz-Friedman Lorenz Studer Simon Powell Zvi Fuks E. Jane Albert Hubbard Richard Kolesnick 《PloS one》2015,10(6)
Mammalian NOTCH1-4 receptors are all associated with human malignancy, although exact roles remain enigmatic. Here we employ glp-1(ar202), a temperature-sensitive gain-of-function C. elegans NOTCH mutant, to delineate NOTCH-driven tumor responses to radiotherapy. At ≤20°C, glp-1(ar202) is wild-type, whereas at 25°C it forms a germline stem cell⁄progenitor cell tumor reminiscent of human cancer. We identify a NOTCH tumor phenotype in which all tumor cells traffic rapidly to G2⁄M post-irradiation, attempt to repair DNA strand breaks exclusively via homology-driven repair, and when this fails die by mitotic death. Homology-driven repair inactivation is dramatically radiosensitizing. We show that these concepts translate directly to human cancer models. 相似文献