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31.
Relationships between wild bees,hoverflies and pollination success in apple orchards with different landscape contexts
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Ádám Kőrösi László Somay Zoltán Elek Viktor Markó Miklós Sárospataki Réka Bakos Ákos Varga Katinka Nyisztor András Báldi 《Agricultural and Forest Entomology》2016,18(1):68-75
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Chiral Separation of Uncharged Pomalidomide Enantiomers Using Carboxymethyl‐β‐Cyclodextrin: A Validated Capillary Electrophoretic Method
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The racemic mixture of pomalidomide (POM), a second‐generation immunomodulatory uncharged drug, was separated into enantiomers by capillary zone electrophoresis for the first time. Seven different chargeable cyclodextrin (CD) derivatives were screened as complexing agents and chiral selectors, investigating the stability of the POM‐CD inclusion complexes and their enantiodiscriminating capacities. Based on preliminary experiments, carboxymethyl‐β‐CD (CM‐β‐CD) was found to be the most effective chiral selector. Factors influencing enantioseparation were systematically optimized, using an orthogonal experimental design. Optimal parameters (background electrolyte [BGE]: 50 mM Tris‐acetate buffer, pH 6.5, containing 15 mM CM‐β‐CD; capillary temperature: 20°C; voltage applied +15 kV) allowed baseline separation of POM enantiomers with a resolution as high as 4.87. The developed method was validated, in terms of sensitivity (limit of detection and limit of quantification), linearity, accuracy, repeatability, and intermediate precision. Chirality 28:199–203, 2016. © 2015 Wiley Periodicals, Inc. 相似文献
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Mohammadi M Chalavi V Novakova-Sura M Laliberté JF Sylvestre M 《Biotechnology and bioengineering》2007,97(3):496-505
Optimized plant-microbe bioremediation processes in which the plant initiates the metabolism of xenobiotics and releases the metabolites in the rhizosphere to be further degraded by the rhizobacteria is a promising alternative to restore contaminated sites in situ. However, such processes require that plants produce the metabolites that bacteria can readily oxidize. The biphenyl dioxygenase is the first enzyme of the bacterial catabolic pathway involved in the degradation of polychlorinated biphenyls. This enzyme consists of three components: the two sub-unit oxygenase (BphAE) containing a Rieske-type iron-sulfur cluster and a mononuclear iron center, the Rieske-type ferredoxin (BphF), and the FAD-containing ferredoxin reductase (BphG). In this work, based on analyses with Nicotiana benthamiana plants transiently expressing the biphenyl dioxygenase genes from Burkholderia xenovorans LB400 and transgenic Nicotiana tabacum plants transformed with each of these four genes, we have shown that each of the three biphenyl dioxygenase components can be produced individually as active protein in tobacco plants. Therefore, when BphAE, BphF, and BphG purified from plant were used to catalyze the oxygenation of 4-chlorobiphenyl, detectable amounts of 2,3-dihydro-2, 3-dihydroxy-4'-chlorobiphenyl were produced. This suggests that creating transgenic plants expressing simultaneously all four genes required to produce active biphenyl dioxygenase is feasible. 相似文献
37.
Gene expression dynamics in deer antler: mesenchymal differentiation toward chondrogenesis 总被引:6,自引:0,他引:6
Gyurján I Molnár A Borsy A Stéger V Hackler L Zomborszky Z Papp P Duda E Deák F Lakatos P Puskás LG Orosz L 《Molecular genetics and genomics : MGG》2007,277(3):221-235
Annual re-growth of deer antler represents a unique example of complete organ regeneration. Because antler mesenchymal cells
retain their embryonic capacity to develop into cartilage or bone, studying antler development provides a natural system to
follow gene expression changes during mesenchymal differentiation toward chondrogenic/osteogenic lineage. To identify novel
genes involved either in early events of mesenchymal cell specialization or in robust bone development, we have introduced
a 3 K heterologous microarray set-up (deer cDNA versus mouse template). Fifteen genes were differentially expressed; genes
for housekeeping, regulatory functions (components of different signaling pathways, including FGF, TGFβ, Wnt), and genes encoding
members of the Polycomb group were represented. Expression dynamics for genes are visualized by an expression logo. The expression
profile of the gene C21orf70 of unknown function is described along with the effects when over-expressed; furthermore the nuclear localization of the
cognate protein is shown. In this report, we demonstrate the particular advantage of the velvet antler model in bone research
for: (1) identification of mesenchymal and precartilaginous genes and (2) targeting genes upregulated in robust cartilage
development.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
38.
Benard Bogonko Nyakundi Andrea Tóth Enikő Balogh Béla Nagy Judit Erdei Bernhard Ryffel György Paragh Mario D. Cordero Viktória Jeney 《生物化学与生物物理学报:疾病的分子基础》2019,1865(2):464-475
Damage associated molecular patterns (DAMPs) are released form red blood cells (RBCs) during intravascular hemolysis (IVH). Extracellular heme, with its pro-oxidant, pro-inflammatory and cytotoxic effects, is sensed by innate immune cells through pattern recognition receptors such as toll-like receptor 4 and nucleotide-binding domain and leucine rich repeat containing family, pyrin domain containing 3 (NLRP3), while free availability of heme is strictly controlled. Here we investigated the involvement of different hemoglobin (Hb) forms in hemolysis-associated inflammatory responses.We found that after IVH most of the extracellular heme molecules are localized in oxidized Hb forms. IVH was associated with caspase-1 activation and formation of mature IL-1β in plasma and in the liver of C57BL/6 mice. We showed that ferrylHb (FHb) induces active IL-1β production in LPS-primed macrophages in vitro and triggered intraperitoneal recruitment of neutrophils and monocytes, caspase-1 activation and active IL-1β formation in the liver of C57BL/6 mice. NLRP3 deficiency provided a survival advantage upon IVH, without influencing the extent of RBC lysis or the accumulation of oxidized Hb forms. However, both hemolysis-induced and FHb-induced pro-inflammatory responses were largely attenuated in Nlrp3?/? mice.Taken together, FHb is a potent trigger of NLRP3 activation and production of IL-1β in vitro and in vivo, suggesting that FHb may contribute to hemolysis-induced inflammation. Identification of RBC-derived DAMPs might allow us to develop new therapeutic approaches for hemolytic diseases. 相似文献
39.
Schwertz DW Vizgirda V Solaro RJ Piano MR Ryjewski C 《Molecular and cellular biochemistry》1999,200(1-2):143-153
A number of investigations in humans and animals suggest that there may be intrinsic sex-associated differences in cardiac function. Using left atrial preparations from male and female rat hearts, we examined differences in myocardial function and response to adrenergic agonists. Contractile parameters were measured in isolated atria by conventional isometric methods in the absence or presence of isoproterenol or phenylephrine. Responsiveness to Ca2+ was measured in detergent-skinned atrial fibers and actomyosin ATPase activity was measured in isolated myofibrils. Tetanic contractions were generated by treating the atrium with ryanodine followed by high frequency stimulation. Developed force was greater and maximal rates of contraction and relaxation were more rapid in the female atrium. The relationship between Ca2+ concentration and force in both intact atria and detergent-skinned atrial fibers in females fell to the left of that for males. At low Ca2+ concentrations, skinned fibers from female atria generated more force and myofibrils from female atria had higher myosin ATPase activity than males. Tetanic contraction in the presence of high extracellular Ca2+ was greater in female atria. Male atrium had larger inotropic responses to isoproterenol and to phenylephrine, but drug-elicited cAMP and inositol phosphate production did not differ between sexes. The results demonstrate sex-related differences in atrial function that can be partially explained by greater myofibrillar Ca2+-sensitivity in females. A potential contribution of sarcolemmal Ca2+ influx is suggested by greater tetanic contraction in ryanodine-treated female atrium. The larger response of males to adrenergic stimulation does not appear to be explained by higher production of relevant second messengers. Future studies will investigate the role of sex hormones in these sexually dimorphic responses and may indicate a need for gender-specific therapeutic interventions for myocardial dysfunction. 相似文献
40.
Soderholm J Bhattacharyya D Strongin D Markovitz V Connerly PL Reinke CA Glick BS 《Developmental cell》2004,6(5):649-659
COPII vesicles assemble at ER subdomains called transitional ER (tER) sites, but the mechanism that generates tER sites is unknown. To study tER biogenesis, we analyzed the transmembrane protein Sec12, which initiates COPII vesicle formation. Sec12 is concentrated at discrete tER sites in the budding yeast Pichia pastoris. We find that P. pastoris Sec12 exchanges rapidly between tER sites and the general ER. The tER localization of Sec12 is saturable and is mediated by interaction of the Sec12 cytosolic domain with a partner component. This interaction apparently requires oligomerization of the Sec12 lumenal domain. Redistribution of P. pastoris Sec12 to the general ER does not perturb the localization of downstream tER components, suggesting that Sec12 and other COPII proteins associate with a tER scaffold. These results provide evidence that tER sites form by a network of dynamic associations at the cytosolic face of the ER. 相似文献