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71.
Aysun Çapcı Karagöz Christoph Reiter Ean-Jeong Seo Lisa Gruber Friedrich Hahn Maria Leidenberger Volker Klein Frank Hampel Oliver Friedrich Manfred Marschall Barbara Kappes Thomas Efferth Svetlana B. Tsogoeva 《Bioorganic & medicinal chemistry》2018,26(12):3610-3618
Hybridization of natural products has high potential to further improve their activities and may produce synergistic effects between linked pharmacophores. Here we report synthesis of nine new hybrids of natural products egonol, homoegonol, thymoquinone and artemisinin and evaluation of their activities against P. falciparum 3D7 parasites, human cytomegalovirus, sensitive and multidrug-resistant human leukemia cells. Most of the new hybrids exceed their parent compounds in antimalarial, antiviral and antileukemia activities and in some cases show higher in vitro efficacy than clinically used reference drugs chloroquine, ganciclovir and doxorubicin. Combined, our findings stress the high potency of these hybrids and encourages further use of the hybridization concept in applied pharmacological research. 相似文献
72.
Mustafa Durmuş Ali Rıza Kosker Yeşim Ozogul Mehmet Aydin Yılmaz UÇar Deniz Ayas 《人类与生态风险评估》2018,24(3):731-742
The effects of seasonal and sexual differences on the levels of macro, trace element, and toxic metal levels in Mullus barbatus were investigated using the ICP-MS. The quantity relationships of macro elements were found as K>P>Na>Ca>Mg for male, P>K>Na>Ca>Mg in female; the quantity relationships of trace elements were determined as Fe>Zn>Mn>Mo>Se>Cu>Ni>Co in male, Fe>Zn>Mn>Se>Cu>Ni>Mo>Co in female; and the quantity relationship of toxic elements were found as As>Pb>Cd in both male and female. Macro, trace, and toxic metal levels showed no significant differences (p > .05) in terms of sexuality, but demonstrated seasonal differences (p > .05). Overall, the highest level of macro elements was determined in the autumn, while the high level of trace elements was measured in the winter. The As, Cd, and Pb levels in the muscle tissue of red mullet fish were higher than acceptable limits. However, when the Estimated Daily Intake (EDI) and Estimated Weekly Intake (EWI) of both toxic metals are considered, they appear to be below acceptable limits. As a result, it was determined that the red mullet had been contaminated with toxic metals (Cd and Pb) but their levels according to EDI and EWI were below the limit. 相似文献
73.
74.
Vitamin requirements, determined by two different methods, and other nutritional characteristics of 46 psychrophobic and 30
non-psychrophobic yeasts were investigated. Vitamin requirements and induced nutritional imbalances emerged as criteria for
definingCandida slooffii. Strains of this species behaved uniformly. Variations in vitamin requirements of strains ofSaccharomyces telluris, Torulopsis bovina andTorulopsis pintolopesii were confirmed. The choline requirement exhibited by several strains (by as many as 86% inS. telluris) was evident on a simple defined medium without methionine, but not on Wickerham's vitamin-free basal medium. The group of
choline-requiring strains comprised strains responding similarly to choline or methionine, and some strains growing with choline
but not with methionine on short incubation. Other frequently required vitamins were biotin, pantothenate, thiamine, nicotinic
acid, pyridoxine, and inositol.
Fellow of the John Simon Guggenheim Memorial Foundation.
Fellow of the National Research Council (Brasil). 相似文献
75.
76.
Tuğba Keskin Gündoğdu İrem Deniz Gülizar Çalışkan Erdem Sefa Şahin 《Critical reviews in biotechnology》2016,36(2):368-388
Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett–Burman design, Taguchi design, Box–Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed. 相似文献
77.
Emrah Hicazi Aksu Fatih Mehmet Kandemir Serdar Altun Sefa Küçükler Selim Çomaklı Ali Doğan Ömür 《Journal of biochemical and molecular toxicology》2016,30(10):513-520
Cisplatin (CP) treatment causes the damage in male reproductive system. Carvacrol (CARV) is an antioxidant that is naturally found in some plants. We aimed to investigate the effect of CARV on CP‐induced reproductive toxicity in male rats. Eighteen adult male Sprague–Dawley rats were used. The control group (n = 6) was treated orally with physiological saline (PS) daily for 14 days and a single intraperitoneal (IP) PS injection on day 10. The CP group (n = 6) was administered with daily oral PS for 14 days and a single IP injection of 10 mg/kg CP on day 10. The CARV + CP group (n = 6) was treated with daily 75 mg/kg oral CARV for 14 days and a single IP injection of 10 mg/kg CP on day 10. CP treatment caused the damage on some spermatological parameters (motility, live sperm rate, and abnormal sperm rate), increased the oxidative stress, and induced testicular degeneration and apoptosis. However, CARV treatment mitigates CP‐induced reproductive toxicity. 相似文献
78.
79.
JEAN-FRANÇOIS ARNAUD STÉPHANE FÉNART CÉCILE GODÉ SYLVIE DELEDICQUE PASCAL TOUZET JOËL CUGUEN 《Molecular ecology》2009,18(15):3201-3215
Introgression arising from crop-to-wild gene flow provides novel sources of genetic variation in plant species complexes. Hybridization within the Beta vulgaris species complex is of immediate concern; crop lineages ( B . vulgaris ssp. vulgaris ) hybridize easily with their wild relatives ( B . vulgaris ssp. maritima ) thereby threatening wild beet gene diversity with genetic swamping. Hybridization 'hotspots' occur in European seed production areas because inland ruderal wild beets occur and reproduce in sympatry with cultivated beets. We studied gene flow occurring between seed-producing cultivars and ruderal wild B . vulgaris in southwestern France to determine whether feral beets, arising from unharvested cultivated seed, represent an opportunity for crop-to-wild gene flow. We surveyed 42 inland ruderal beet populations located near seed production fields for nucleo-cytoplasmic variation and used a cytoplasmic marker diagnostic of cultivated lines. Occurrence of cultivated-type cytoplasm within ruderal populations clearly reflected events of crop seed escape. However, we found no genetic signatures of nuclear cultivated gene introgression, which suggests past introgression of cultivated cytoplasm into a wild nuclear background through seed escape rather than recent direct pollen flow. Overall, patterns of genetic structure suggested that inland ruderal wild beet populations act as a metapopulation, with founding events involving a few sib groups, followed by low rates of seed or pollen gene flow after populations are established. Altogether, our results indicate that a long-lived seed bank plays a key role in maintaining cultivated-type cytoplasm in the wild and highlight the need for careful management of seed production areas where wild and cultivated relatives co-occur. 相似文献
80.
JÉRÔME ORIVEL JULIEN GRANGIER JULIEN FOUCAUD JULIEN LE BRETON FRANÇOIS‐XAVIER ANDRÈS HERVÉ JOURDAN JACQUES H. C. DELABIE DENIS FOURNIER PHILIPPE CERDAN BENOIT FACON ARNAUD ESTOUP ALAIN DEJEAN 《Ecological Entomology》2009,34(4):504-512
Abstract 1. The biology of most invasive species in their native geographical areas remains largely unknown. Such studies are, however, crucial in shedding light on the ecological and evolutionary processes underlying biological invasions. 2. The present study focuses on the little fire ant Wasmannia auropunctata, a species native to Central and South America that has been widely introduced and which has become invasive throughout the tropics. We characterise and compare several ecological traits of native populations in French Guiana with those in one of its introduced ranges, New Caledonia. 3. We found ecologically heterogeneous populations of W. auropunctata coexisting in the species’ native geographical area. First, we found populations restricted to naturally perturbed areas (particularly floodplains) within the primary forest, and absent from the surrounding forest areas. These populations were characterised by low nest and worker densities. Second, we found dominant populations in recent anthropogenic areas (e.g. secondary forest or forest edge along road) characterised by high nest and worker densities, and associated with low ant species richness. The local dominance of W. auropunctata in such areas can be due to the displacement of other species (cause) or the filling‐up of empty habitats unsuitable to other ants (effect). With respect to their demographic features and ant species richness, the populations of native anthropogenic habitats were to a large extent similar to the invasive populations introduced into remote areas. 4. The results point to the need for greater research efforts to better understand the ecological and demographic features of invasive species within their native ranges. 相似文献