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191.
Janecka A Fichna J Kosson P Zalewska-Kaszubska J Krajewska U Mirowski M Rozalski M 《Regulatory peptides》2004,120(1-3):237-241
In the present study, we reported on the synthesis of two new mu-opioid peptide analogs, [D-1-Nal3]morphiceptin and [D-1-Nal4]-morphiceptin [1-Nal=3-(1-naphthyl)-alanine] which expressed receptor binding affinities at least at the level of the primary opioid ligands. The new analogs also labeled mu-opioid receptors on the cells of human breast cancer MCF-7 cell line with affinity much higher than that of endomorphins and morphiceptin, the well-known mu-selective opioid peptides. However, none of the tested peptides significantly decreased cell proliferation of MCF-7 cells. 相似文献
192.
Smýkalová Iva Vrbová Miroslava Cvečková Magdalena Plačková Lenka Žukauskaitė Asta Zatloukal Marek Hrdlička Jakub Plíhalová Lucie Doležal Karel Griga Miroslav 《Plant Cell, Tissue and Organ Culture》2019,139(2):381-394
Plant Cell, Tissue and Organ Culture (PCTOC) - The biotechnological utilization (genetic transformation, gene editing) of industrial hemp (Cannabis sativa L.) has been hampered by a lack of robust... 相似文献
193.
André Nel Jakub Prokop Patricia Nel Philippe Grandcolas Di‐Ying Huang Patrick Roques Eric Guilbert Ondřej Dostál Jacek Szwedo 《Journal of morphology》2012,273(5):480-506
Two different patterns of wing venation are currently supposed to be present in each of the three orders of Paraneoptera. This is unlikely compared with the situation in other insects where only one pattern exists per order. We propose for all Paraneoptera a new and unique interpretation of wing venation pattern, assuming that the convex cubitus anterior gets fused with the common stem of median and radial veins at or very near to wing base, after separation from concave cubitus posterior, and re‐emerges more distally from R + M stem. Thereafter, the vein between concave cubitus posterior and CuA is a specialized crossvein called “cua‐cup,” proximally concave and distally convex. We show that despite some variations, that is, cua‐cup can vary from absent to hypertrophic; CuA can re‐emerge together with M or not, or even completely disappear, this new interpretation explains all situations among all fossil and recent paraneopteran lineages. We propose that the characters “CuA fused in a common stem with R and M”and “presence of specialized crossvein cua‐cup” are venation apomorphies that support the monophyly of the Paraneoptera. In the light of these characters, we reinterpret several Palaeozoic and early Mesozoic fossils that were ascribed to Paraneoptera, and confirm the attribution of several to this superorder as well as possible attribution of Zygopsocidae (Zygopsocus permianus Tillyard, 1935) as oldest Psocodea. We discuss the situation in extinct Hypoperlida and Miomoptera, suggesting that both orders could well be polyphyletic, with taxa related to Archaeorthoptera, Paraneoptera, or even Holometabola. The Carboniferous Protoprosbolidae is resurrected and retransferred into the Paraneoptera. The genus Lithoscytina is restored. The miomopteran Eodelopterum priscum Schmidt, 1962 is newly revised and considered as a fern pinnule. In addition, the new paraneopteran Bruayaphis oudardi gen. nov. et sp. nov. is described fromthe Upper Carboniferous of France (see Supporting Information). J. Morphol., 2012. © 2011 Wiley Periodicals, Inc. 相似文献
194.
195.
Hyun Myung Lee Rudolf Andrys Jakub Jonczyk Kyuneun Kim Avinash G. Vishakantegowda David Malinak Adam Skarka Monika Schmidt Michaela Vaskova Kamil Latka Marek Bajda Young-Sik Jung Barbara Malawska Kamil Musilek 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):437
The pyridinium-2-carbaldoximes with quinolinium carboxamide moiety were designed and synthesised as cholinesterase reactivators. The prepared compounds showed intermediate-to-high inhibition of both cholinesterases when compared to standard oximes. Their reactivation ability was evaluated in vitro on human recombinant acetylcholinesterase (hrAChE) and human recombinant butyrylcholinesterase (hrBChE) inhibited by nerve agent surrogates (NIMP, NEMP, and NEDPA) or paraoxon. In the reactivation screening, one compound was able to reactivate hrAChE inhibited by all used organophosphates and two novel compounds were able to reactivate NIMP/NEMP-hrBChE. The reactivation kinetics revealed compound 11 that proved to be excellent reactivator of paraoxon-hrAChE better to obidoxime and showed increased reactivation of NIMP/NEMP-hrBChE, although worse to obidoxime. The molecular interactions of studied reactivators were further identified by in silico calculations. Molecular modelling results revealed the importance of creation of the pre-reactivation complex that could lead to better reactivation of both cholinesterases together with reducing particular interactions for lower intrinsic inhibition by the oxime. 相似文献
196.
Dong LF Jameson VJ Tilly D Cerny J Mahdavian E Marín-Hernández A Hernández-Esquivel L Rodríguez-Enríquez S Stursa J Witting PK Stantic B Rohlena J Truksa J Kluckova K Dyason JC Ledvina M Salvatore BA Moreno-Sánchez R Coster MJ Ralph SJ Smith RA Neuzil J 《The Journal of biological chemistry》2011,286(5):3717-3728
Mitochondrial complex II (CII) has been recently identified as a novel target for anti-cancer drugs. Mitochondrially targeted vitamin E succinate (MitoVES) is modified so that it is preferentially localized to mitochondria, greatly enhancing its pro-apoptotic and anti-cancer activity. Using genetically manipulated cells, MitoVES caused apoptosis and generation of reactive oxygen species (ROS) in CII-proficient malignant cells but not their CII-dysfunctional counterparts. MitoVES inhibited the succinate dehydrogenase (SDH) activity of CII with IC(50) of 80 μM, whereas the electron transfer from CII to CIII was inhibited with IC(50) of 1.5 μM. The agent had no effect either on the enzymatic activity of CI or on electron transfer from CI to CIII. Over 24 h, MitoVES caused stabilization of the oxygen-dependent destruction domain of HIF1α fused to GFP, indicating promotion of the state of pseudohypoxia. Molecular modeling predicted the succinyl group anchored into the proximal CII ubiquinone (UbQ)-binding site and successively reduced interaction energies for serially shorter phytyl chain homologs of MitoVES correlated with their lower effects on apoptosis induction, ROS generation, and SDH activity. Mutation of the UbQ-binding Ser(68) within the proximal site of the CII SDHC subunit (S68A or S68L) suppressed both ROS generation and apoptosis induction by MitoVES. In vivo studies indicated that MitoVES also acts by causing pseudohypoxia in the context of tumor suppression. We propose that mitochondrial targeting of VES with an 11-carbon chain localizes the agent into an ideal position across the interface of the mitochondrial inner membrane and matrix, optimizing its biological effects as an anti-cancer drug. 相似文献
197.
Jakub Gburek Jerzy Osada Mariusz Siekierka Maria Warwas 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》1995,112(4)
Chicken cystatin (mixed form) was prepared from egg white. Radioactively labeled preparations were administered intravenously to rats. 125I-cystatin disappeared from the rat circulation with a half-life of -73 min. The radiolabeled inhibitor was rapidly taken up by the kidneys. Percoll density gradient analysis showed that it was incorporated into lysosomes. Within 24 hr after the injection of 125I-cystatin, 25% of the administered radioactivity was recovered in the urine, but only 2% was in the protein-bound form. 相似文献
198.
Jakub Straka Abdulaziz S. Alqarni Katerina J?zová Mohammed A. Hannan Ismael A. Hinojosa-Díaz Michael S. Engel 《ZooKeys》2015,(519):117-139
Parasitism of Andrena (Suandrena) savignyi Spinola (Hymenoptera: Andrenidae) by Stylops Kirby (Strepsiptera: Stylopidae) has been recorded only once, and from an individual collected in Egypt almost a century ago, with the parasite described as Stylops
savignyi Hofeneder. The recent rediscovery of this Stylops from an individual of Andrena
savignyi permits a reinterpretation of the species and its affinities among other Stylops. The bee was collected at flowers of Zilla
spinosa (Turra) Prantl. (Brassicaceae) in Amariah, Riyadh, Kingdom of Saudi Arabia. Based on DNA barcode sequences from material sampled across Africa, Asia, and Europe, it is apparent that Stylops
savignyi is conspecific with Stylops
nassonowi Pierce, and we accordingly synonymize this name (syn. n.), with the latter representing the senior and valid name for the species. A differential diagnosis is provided for Stylops
nassonowi and the morphology of the female is described, as well as the first instars. 相似文献
199.
CBSs (cystathionine β-synthases) are eukaryotic PLP (pyridoxal 5 *-phosphate)-dependent proteins that maintain cellular homocysteine homoeostasis and produce cystathionine and hydrogen sulfide. In the present study, we describe a novel structural arrangement of the CBS enzyme encoded by the cbs-1 gene of the nematode Caenorhabditis elegans. The CBS-1 protein contains a unique tandem repeat of two evolutionarily conserved catalytic regions in a single polypeptide chain. These repeats include a catalytically active C-terminal module containing a PLP-binding site and a less conserved N-terminal module that is unable to bind the PLP cofactor and cannot catalyse CBS reactions, as demonstrated by analysis of truncated variants and active-site mutant proteins. In contrast with other metazoan enzymes, CBS-1 lacks the haem and regulatory Bateman domain essential for activation by AdoMet (S-adenosylmethionine) and only forms monomers. We determined the tissue and subcellular distribution of CBS-1 and showed that cbs-1 knockdown by RNA interference leads to delayed development and to an approximately 10-fold elevation of homocysteine concentrations in nematode extracts. The present study provides the first insight into the metabolism of sulfur amino acids and hydrogen sulfide in C. elegans and shows that nematode CBSs possess a structural feature that is unique among CBS proteins. 相似文献
200.
Conditions for conidiation of a natural isolate of Trichoderma atroviride during submerged cultivation in Erlenmeyer flasks and in a laboratory stirred-tank fermenter were optimized. From the simple sugars tested, cellobiose was the best substrate for conidia production while cellulose fines from paper mill waste proved to be a suitable cheap complex carbon source. Optimum temperature for conidiation was 24-26 degrees C, and the required dissolved oxygen level was > 40% saturation. After initial slight decrease during the 1st d after inoculation, the pH of the culture medium constantly increased throughout the sporulation period. Attempts to regulate the pH during fermentation did not improve the spore yields. The most intense formation of conidia took place between 2nd and 3rd d of growth and the overall volumetric productivity of conidia was 4.1-8.2 x 10(9) conidia per L/h. 相似文献