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Oviposition behavior and offspring fitness of the parasitoid Aphidius gifuensis (Ashmead) were compared on three aphid species, Sitobion avenae F., Myzus persicae (Sulzer), and Aphis gossypii Glover using wasps collected from both S. avenae and M. persicae. A. gifuensis produced more mummies and adults on S. avenae and M. persicae than on A. gossypii regardless of the host of origin. Mummy production was influenced by attack rate and percentage of aphids superparasitized. The F1 generations from S. avenae and M. persicae were more female-biased and wasps were larger than those from A. gossypii. Although there were significant differences in development time of A. gifuensis in the three aphid species, the difference was generally shorter than one day. Fewer mummies were produced when A. gifuensis was transferred between S. avenae and M. persicae, but no significant difference was observed in emergence rate, percentage of female offspring, or body size. The effects of host species on A. gifuensis female performance and offspring fitness are discussed, along with the potential for using A. gifuensis to control M. persicae and A. gossypii. 相似文献
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《Phytomedicine》2021
BackgroundFragility fractures due to menopausal osteoporosis are a major cause of morbidity and mortality. Osteoporotic medications have substantial side effects that limit long term use.HypothesesIngestion of a purified extract of Epimedium spp. (EP) is safe, can increase serum levels of prenylflavonoid metabolites, exert positive changes in bone specific alkaline phosphatase (BSAP), suppress of tumor necrosis factor receptor associated factor 6 (TRAF6) protein in osteoclast-precursor monocytes in peripheral blood and therefore have the potential to reduce post-menopausal bone loss.Study design & methodsHealthy postmenopausal women were randomized in a double-blind fashion to consume either EP prenylflavonoid extract (740 mg daily) or placebo daily for 6 weeks. The main outcome measures were safety and pharmacokinetics of EP flavonoids. Fasting blood was collected at 3- and 6-weeks, and two weeks after stopping medication for safety evaluations and measurement of BSAP. Peripheral blood monocytes were harvested for measurement of TRAF6 levels. Serum levels of the EP metabolites icariin, icariside I & II, icaritin and desmethylicaritin were measured using tandem mass spectrometry, and non-compartmental pharmacokinetic analyses performed using WinNonlin software.ResultsBetween October 2018 and Jun 2020, 58 postmenopausal women, aged 57.9 ± 8.9 years, were randomized and completed the study. Consumption of EP prenylflavonoids was not associated with any significant adverse symptoms, with no changes in hepatic, hematological, and renal parameters observed. The main metabolites detected in sera after ingestion of EP prenylflavonoid capsules were desmethylicaritin, icaritin and icariside II. Icariin and icariside I were below detection levels. Ingestion of EP prenylflavonoids induced a median Cmax and AUC0→∞ for desmethylicaritin of 60.9 nM, and 157.9 nM ×day, respectively; and were associated with higher levels of BSAP (p < 0.05) and a trend (p = 0.068) towards lower levels of TRAF6 in peripheral blood monocytes eight weeks after commencing prenylflavonoid ingestion. Prenylflavonoid metabolites were not detected in the sera of placebo participants.ConclusionsDespite the widespread consumption of EP extracts, the safety, mechanisms of action of their bioactive compounds, and therapeutic indications in humans are unknown. Daily consumption of EP prenylflavonoids for six weeks was safe. The predominant metabolite in sera was desmethylicaritin. Rise in prenylflavonoid metabolites was associated with higher levels of the bone anabolic marker BSAP, suggesting potential therapeutic value for post-menopausal osteoporosis. 相似文献
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Sensitive biological measures of river ecosystem quality are needed to assess, maintain or restore ecological conditions of water bodies. Since our understanding of these complex systems is imperfect, decision-making requires recognizing uncertainty. In this study, a new predictive multi-metric index based on fish functional traits was developed to assess French rivers. Information on fish assemblage structure, local environment and human-induced disturbances of 1654 French river sites was compiled. A Bayesian framework was used to predict theoretical metric values in absence of human pressure and to estimate the uncertainty associated with these predictions. The uncertainty associated with the index score gives the confidence associated with the evaluation of site ecological conditions.Among the 228 potential metrics tested, only 11 were retained for the index computation. The final index is independent from natural variability and sensitive to human-induced disturbances. In particular, it is affected by the accumulation of different degradations and specific degradations including hydrological perturbations. Predictive uncertainty is globally lower for IPR+ than for underlying metrics.This new methodology seems appropriate to develop bio-indication tools accounting for uncertainty related to reference condition definition and could be extended to other biological groups and areas. Our results support the use of multi-metric indexes to assess rivers and strengthen the idea that examination of uncertainty could contribute greatly to the improvement of the assessment power of bio-indicators. 相似文献
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《European journal of protistology》2014,50(5):496-508
Three species of Diophrys, D. peculiaris nov. spec., D. cf. scutum and D. oligothrix, isolated from the New Nagasaki Fishing Port, Nagasaki, Japan, were investigated using live observation and protargol impregnation. Diophrys peculiaris nov. spec. can be recognized by having two characteristic clusters of rod-like structures and two groups of dikinetids located on anterior dorsal portion of cell. Morphogenetic data show that this part of the life cycle basically proceeds as in congeners, except for the formation of dikinetids under the rod-like structures. In the opisthe, the origin of dikinetids under the rod-like structures is still unknown, but the old dikinetids under the rod-like structures may be retained by the proter. The Japanese population of Diophrys cf. scutum resembles other populations of D. scutum well except for moniliform macronuclear segments. Our populations of D. oligothrix correspond well with other populations in terms of general morphology and ciliary pattern, in particular the continuous dorsal kineties with loosely arranged cilia. 相似文献
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Oxidative stress is important for the initiation and progression of cancers, which confers the cells with a survival advantage by inducing oxidative adaption and drug resistance. Therefore, developing strategies to promote oxidative stress-induced cytotoxicity could be important for cancer therapy. Herein, we found that H2O2-mediated oxidative stress increases TRPV2 expression in human hepatoma (HepG2 and Huh-7) cells. This occurred at the mRNA and protein levels in a dose-dependent manner. The significance of TRPV2 in promoting H2O2-induced cell death was demonstrated in gain and loss of function studies with overexpression and knockdown of TRPV2, respectively. Mechanistically, H2O2-induced cell death involves inhibition of pro-survival signaling proteins (Akt, Nrf2) and activation of pro-death signaling proteins (p38, JNK1). Overexpression of TRPV2 in H2O2-treated hepatoma cells aggravates the inhibition of Akt and Nrf2, while it enhances the activation of p38 and JNK1 at the early stage of cell death. Interestingly, increased expression of TRPV2 in HepG2 cells improved the efficacy of stress-associated chemicals to induce cell death. Our findings suggest that TRPV2 acts as an important enhancer for H2O2-induced cytotoxicity. This process occurred by the inhibition of Akt and Nrf2 as well as the early activation of p38 and JNK1. These findings have important implications for inhibition of oxidative adaption and drug resistance. 相似文献