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381.
Kinetic Resolution of Profens by Enantioselective Esterification Catalyzed by Candida antarctica and Candida rugosa Lipases
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Profens (2‐arylpropionic acids) are known as one of the major nonsteroidal antiinflammatory drugs (NSAIDs) used in the treatment of inflammation associated with tissue injury. The inflammatory activity of profens is mainly due to their (S)‐enantiomer, whereas they are commercially available not only as pure enantiomers, but as racemates as well. There are several methods widely used in order to obtain enantiomerically pure compounds, however, the kinetic resolution with the application of lipases as biocatalysts may have an added advantage in the production of optically pure active pharmaceutical ingredients, such as milder reaction conditions, reduced energy requirements, and production costs. The aim of this study was to compare the results described in the literature in the case of the influence of reaction medium, alcohol moiety, and reaction temperature on the catalytic activity of lipases from Candida antarctica and Candida rugosa. Chirality 26:663–669, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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383.
Tomasz W. Turowski Simon Lebaron Elodie Zhang Lauri Peil Tatiana Dudnakova Elisabeth Petfalski Sander Granneman Juri Rappsilber David Tollervey 《Nucleic acids research》2014,42(19):12189-12199
During the last step in 40S ribosome subunit biogenesis, the PIN-domain endonuclease Nob1 cleaves the 20S pre-rRNA at site D, to form the mature 18S rRNAs. Here we report that cleavage occurs in particles that have largely been stripped of previously characterized pre-40S components, but retain the endonuclease Nob1, its binding partner Pno1 (Dim2) and the atypical ATPase Rio1. Within the Rio1-associated pre-40S particles, in vitro pre-rRNA cleavage was strongly stimulated by ATP and required nucleotide binding by Rio1. In vivo binding sites for Rio1, Pno1 and Nob1 were mapped by UV cross-linking in actively growing cells. Nob1 and Pno1 bind overlapping regions within the internal transcribed spacer 1, and both bind directly over cleavage site D. Binding sites for Rio1 were within the core of the 18S rRNA, overlapping tRNA interaction sites and distinct from the related kinase Rio2. Site D cleavage occurs within pre-40S-60S complexes and Rio1-associated particles efficiently assemble into these complexes, whereas Pno1 appeared to be depleted relative to Nob1. We speculate that Rio1-mediated dissociation of Pno1 from cleavage site D is the trigger for final 18S rRNA maturation. 相似文献
384.
Aneta Mirecka Katarzyna Paszkowska-Szczur Rodney J. Scott Bohdan Górski Thierry van de Wetering Dominika Wokołorczyk Tomasz Gromowski Pablo Serrano-Fernandez Cezary Cybulski Aniruddh Kashyap Satish Gupta Adam Gołąb Marcin Słojewski Andrzej Sikorski Jan Lubiński Tadeusz Dębniak 《Gene》2014
The genetic basis of prostate cancer (PC) is complex and appears to involve multiple susceptibility genes. A number of studies have evaluated a possible correlation between several NER gene polymorphisms and PC risk, but most of them evaluated only single SNPs among XP genes and the results remain inconsistent. Out of 94 SNPs located in seven XP genes (XPA–XPG) a total of 15 SNPs were assayed in 720 unselected patients with PC and compared to 1121 healthy adults. An increased risk of disease was associated with the XPD SNP, rs1799793 (Asp312Asn) AG genotype (OR = 2.60; p < 0.001) and with the AA genotype (OR = 531; p < 0.0001) compared to the control population. Haplotype analysis of XPD revealed one protective haplotype and four associated with an increased disease risk, which showed that the A allele (XPD rs1799793) appeared to drive the main effect on promoting prostate cancer risk. Polymorphism in XPD gene appears to be associated with the risk of prostate cancer. 相似文献
385.
Tomasz Dlugosz 《Electromagnetic biology and medicine》2014,33(3):236-240
This article discusses mutual interactions phenomena especially in the case of Transverse ElectroMagnetic (TEM) cell applications as an exposure system in technical and biomedical studies. Problem of mutual interactions between tested objects placed in the electromagnetic field (EMF) is described. A new device for exposure system is presented. Its role is elimination of mentioned harmful phenomenon that leads to falsifications of results. 相似文献
386.
The challenges of understanding glycolipid functions: An open outlook based on molecular simulations
Moutusi Manna Tomasz Róg Ilpo Vattulainen 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(8):1130-1145
Glycolipids are the most complex lipid type in cell membranes, characterized by a great diversity of different structures and functions. The underlying atomistic/molecular interactions and mechanisms associated with these functions are not well understood. Here we discuss how atomistic and molecular simulations can be used to shed light on the role of glycolipids in membrane structure and dynamics, receptor function, and other phenomena related to emergence of diseases such as Parkinson's. The cases we discuss highlight the challenge to understand how glycolipids function in cell membranes, and the significant added value that one would gain by bridging molecular simulations with experiments. This article is part of a Special Issue entitled Tools to study lipid functions. 相似文献
387.
Ewa M. Slominska Tomasz Borkowski Iwona Rybakowska Magdalena Abramowicz-Glinka Czesława Orlewska 《Nucleosides, nucleotides & nucleic acids》2014,33(4-6):353-357
4-Pyridone-3-carboxamide-1-beta-D-ribonucleoside (4PYR) is an endogenously produced nucleoside that has recently been identified as a substrate for intracellular phosphorylation to form nucleotide derivatives. Low level of 4PYR is normally present in human plasma, but 4PYR massively accumulates in patients with renal failure. This study aimed to evaluate effects of 4PYR and its monophosphate derivative (4PYMP) on several enzymes of nucleotide metabolism in homogenates and intact cells. Activities of adenosine monophosphate deaminase (AMPD), adenosine deaminase, ecto-5′-nucleotidase (e5NT), adenine phosphoribosyltransferase (APRT), hypoxanthine/guanine phosphoribosyltransferase, purine nucleoside phosphorylase, and S-adenosylhomocysteine hydrolase (SAHH) were evaluated in erythrocyte lysates, rat heart homogenates, and in the intact rat cardiomyocytes by high performance liquid chromatography–based assays. 4PYMP caused significant inhibition of AMPD in both erythrocyte lysate and heart homogenate with 50% inhibitory concentration (IC50) of 74 and 55 μM, respectively. Inhibition of e5NT in heart homogenates was also noted with IC50 of 63 μM. 4PYMP slightly inhibited APRT and 4PYR caused moderate activation of SAHH. No effects on other enzymes studied were noted. Inhibition of AMPD by 4PYMP in homogenates was confirmed in the intact cell experiments with isolated cardiomyocytes that were allowed to accumulate 4PYMP by incubation with 4PYR. We conclude that among pathways studied, most important is the effect of 4PYMP on AMPD and that such effect could be one of the consequences of elevated plasma 4PYR concentration. 相似文献
388.
Artur Dzialuk Igor Chybicki Roman Gout Tomasz Mączka Peter Fleischer Heino Konrad Alexandru Lucian Curtu Nicolae Sofletea Alain Valadon 《Conservation Genetics》2014,15(6):1433-1445
In Europe, most of the alpine timberline ecotone has been altered by human activities and climate change. Hence, mountain forests are of the highest conservation interest. Here, we screened 25 populations of Swiss stone pine (Pinus cembra L.) from the Carpathians and the Alps, using a set of ten microsatellite primers to assess the relative conservation value of populations sampled in Polish and Slovak Tatra National Parks, where potential extinction risk is the highest within the Carpathian range. Although endangered, with small and fragmented populations, P. cembra in the Tatra Mts. shows high levels of allelic richness (AR = 5.0) and observed heterozygosity (H o = 0.554). Our results suggest that anthropogenic habitat fragmentation has had little impact on DNA variation of Swiss stone pine in the Tatra Mts. However, the effects of changing conditions on the genetic structure may occur with a substantial time delay due to the long life span of P. cembra. Moreover, inbreeding depression may occur in the next generations, since we found inbreeding (F IS = 0.063) and elevated coancestry coefficient (θ = 0.062) in all populations. Also a shallow pattern of genetic differentiation between populations was found, indicating recent fragmentation of a common gene pool that formerly occupied a larger range. Therefore, the Tatra Mts. can be considered as a single conservation unit. Based on our results, we suggest possible conservation activities for Swiss stone pine both in Poland and Slovakia. 相似文献
389.
Tomasz Krepski Małgorzata Pilecka-Rapacz Robert Czerniawski Józef Domagała 《Central European Journal of Biology》2014,9(11):1037-1047
The aim of this study was to make a comparative analysis of macrozoobenthos composition at different sites at selected sections of lower the Odra River with relation to different physicochemical factors. The observations were made on the lower section of Odra River at five study sites: two of them were localized in the main channel, one in the left branch of river, another one in the channel carrying post-cooling water from Dolna Odra power plant, and the last one was in the channel connecting both branches of Odra River. At all sites, 26 taxa were found representing by: Bivalvia, Gastropoda, Oligochaeta, Hirudinea, Malacostraca and Insecta. The greatest biodiversity and the highest abundance of zoobenthos organisms were noted in the channel joining the two branches of the river, site 5, characterised by the lowest water flow rates and the densest coverage of the macrophytes at the bottom. Temperature was the sole parameter to be studied that affected the composition of benthic invertebrates. A clearly negative impact of temperature on the diversity of invertebrates was observed only in the channel with post-cooling water discharged from the power plant. 相似文献
390.
Andrzej Zieliński Magdalena Simlat Tomasz Wójtowicz Maria Moś 《Central European Journal of Biology》2014,9(8):823-832
The production of economically important cereals is accompanied by the phenomenon of sprouting which in naked cultivars may limit their reproduction and usability. The objective of the work is to evaluate the susceptibility to sprouting in naked oat cultivars, and to test the usefulness of sprouting indices. In the years 2008–2010 for seeds of 8 cultivars, differing in the degree of sprouting damage, the coefficient of sprouting (Cs) was determined. Germinability (GF), dynamics (GD) and average germination time (GAT) were determined for seeds germinating in the presence of abscisic acid (ABA), gibberellic acid (GA3) and under control conditions. Basing on the falling number (FN) in consecutive days of the sprouting induction, alpha-amylase activity was determined. The highest values of Cs were found in 2008, the year with the highest total rainfall and temperature. In the presence of ABA the GF decreased by 21%, the GAT was 4.7 days longer, and the GD decreased by 55% compared with other substrates. An increase in alpha-amylase activity contributed to a 50%, on average, decrease in FN at 10°C and 30°C after 48 and 24 h of incubation, respectively. In the analyzed years the greatest resistance to sprouting was found for Bullion seeds. 相似文献