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51.
Tribelli Paula M. Pezzoni Magdalena Brito María Gabriela Montesinos Nahuel V. Costa Cristina S. López Nancy I. 《Extremophiles : life under extreme conditions》2020,24(2):265-275
Extremophiles - Pseudomonas extremaustralis is an Antarctic bacterium with high stress resistance, able to grow under cold conditions. It is capable to produce polyhydroxyalkanoates (PHAs) mainly... 相似文献
52.
Magdalena Gajdoov Oldich Sychra Jakub Kreisinger Ondej Sedl
ek Eric Djomo Nana Tom Albrecht Pavel Munclinger 《Ecology and evolution》2020,10(13):6512-6524
Coevolutionary processes that drive the patterns of host–parasite associations can be deduced through congruence analysis of their phylogenies. Feather lice and their avian hosts have previously been used as typical model systems for congruence analysis; however, such analyses are strongly biased toward nonpasserine hosts in the temperate zone. Further, in the Afrotropical region especially, cospeciation studies of lice and birds are entirely missing. This work supplements knowledge of host–parasite associations in lice using cospeciation analysis of feather lice (genus Myrsidea and the Brueelia complex) and their avian hosts in the tropical rainforests of Cameroon. Our analysis revealed a limited number of cospeciation events in both parasite groups. The parasite–host associations in both louse groups were predominantly shaped by host switching. Despite a general dissimilarity in phylogeny for the parasites and hosts, we found significant congruence in host–parasite distance matrices, mainly driven by associations between Brueelia lice and passerine species of the Waxbill (Estrildidae) family, and Myrsidea lice and their Bulbul (Pycnonotidae) host species. As such, our study supports the importance of complex biotic interactions in tropical environments. 相似文献
53.
Cioch-Skoneczny Monika Satora Paweł Skoneczny Szymon Skotniczny Magdalena 《Archives of microbiology》2021,203(1):153-162
Archives of Microbiology - Biodiversity of native yeasts, especially in winemaking, has hidden potential. In order to use the value of non-Saccharomyces strains in wine production and to minimise... 相似文献
54.
Arvidsson Rickard Svanström Magdalena Harvey Simon Sandén Björn A. 《The International Journal of Life Cycle Assessment》2021,26(12):2339-2354
The International Journal of Life Cycle Assessment - Most approaches for energy use assessment in life cycle assessment do not consider the scarcity of energy resources. A few approaches consider... 相似文献
55.
Dagmara Otto-Ślusarczyk Wojciech Graboń Magdalena Mielczarek-Puta Alicja Chrzanowska 《Biochemistry and Biophysics Reports》2021
Leflunomide (LFN) is a well-known immunomodulatory and anti-inflammatory prodrug of teriflunomide (TFN). Due to pyrimidine synthesis inhibition TFN also exhibits potent anticancer effect. Because, there is the strict coupling between the pyrimidine synthesis and the mitochondrial respiratory chain, the oxygen level could modify the cytostatic TNF effect.The aim of the study was to evaluate the cytostatic effect of pharmacologically achievable teriflunomide (TFN) concentrations at physiological oxygen levels, i.e. 1% hypoxia and 10% tissue normoxia compared to 21%oxygen level occurred in routine cell culture environment.The TFN effect was evaluated using TB, MTT and FITC Annexin tests for human primary (SW480) and metastatic (SW620) colon cancer cell lines at various oxygen levels.We demonstrated significant differences between proliferation, survival and apoptosis at 1, 10 and 21% oxygen in primary and metastatic colon cancer cell lines (SW480, SW620) under TFN treatment. The cytostatic TFN effect was more pronounced at hypoxia compared to tissue and atmospheric normoxia in both cancer cell lines, however metastatic cells were more resistant to antiproliferative and proapoptotic TFN action. The early apoptosis was predominant in physiological oxygen tension while in atmospheric normoxia the late apoptosis was induced.Our findings showed that anticancer TFN effect is more strong in physiological oxygen compared to atmospheric normoxia. It suggests that results obtained from in vitro studies could be underestimated. Thus, it gives assumption for future comprehensive studies at real oxygen environment involving TNF use in combination with other antitumor agents affecting oxygen-dependent pyrimidine synthesis. 相似文献
56.
Magdalena Bezanilla 《Molecular biology of the cell》2013,24(16):2491-2493
Historically, cell biologists studied organisms that represented a reasonable sampling of life''s diversity, whereas recently research has narrowed into a few model systems. As a result, the cells of plants have been relatively neglected. Here I choose three examples to illustrate how plants have been informative and could be even more so. Owing to their ease of imaging and genetic tractability, multicellular plant model systems provide a unique opportunity to address long-standing questions in cell biology. 相似文献
57.
Antonio Díaz-Cruz Raquel Guinzberg Ruy Guerra Magdalena Vilchis Daniel Carrasco Francisco J. García-vázquez 《Free radical research》2013,47(6):663-672
It is known that adrenaline promotes hydroxyl radical generation in isolated rat hepatocytes. The aim of this work was to investigate a potential role of NADPH oxidase (Nox) isoforms for an oxidative stress signal in response to adrenaline in hepatocytes. Enriched plasma membranes from isolated rat liver cells were prepared for this purpose. These membranes showed catalytic activity of Nox isoforms, probably Nox 2 based on its complete inhibition with specific antibodies. NADPH was oxidized to convert O2 into superoxide radical, later transformed into H2O2. This enzymatic activity requires previous activation with either 3 mM Mn2+ or guanosine 5′-0-(3-thiotriphosphate) (GTPγS) plus adrenaline. Experimental conditions for activation and catalytic steps were set up: ATP was not required; S0.5 for NADPH was 44 μM; S0.5 for FAD was 8 μM; NADH up to 1 mM was not substrate, and diphenyleneiodonium was inhibitory. Activation with GTPγS plus adrenaline was dose- and Ca2+-dependent and proceeded through α1-adrenergic receptors (AR), whereas β-AR stimulation resulted in inhibition of Nox activity. These results lead us to propose H2O2 as additional transduction signal for adrenaline response in hepatic cells. 相似文献
58.
Joanna Suliburska Pawel Bogdanski Ewa Gajewska Grazyna Kalmus Magdalena Sobieska Wlodzimierz Samborski 《Journal of physiology and biochemistry》2013,69(4):847-853
Some data indicate a potential relationship between insulin resistance level and the concentration of osteoprotegerin (OPG) in the body. There have been few studies concerning OPG level and its relationship with insulin resistance and body composition in young people. The aim of this study was to assess serum osteoprotegerin concentration in obese adolescents, and to evaluate its potential association with insulin resistance. Seventy-eight obese adolescents and 20 healthy volunteers aged 12–18 years were recruited in the study. Selected anthropometrical measurements and blood biochemical analyses were performed. Insulin resistance in the participants was evaluated according to the homeostasis model assessment-insulin resistance (HOMA-IR) protocol. Level of OPG was assessed in serum. Obese subjects had significantly higher HOMA-IR indices and OPG levels in serum than the control group. A significant positive correlation between OPG and insulin resistance was found. It was observed that high concentrations of osteoprotegerin are associated with insulin resistance in obese adolescents. 相似文献
59.
Magdalena Eriksson Bengt Nordeh Bengt Jernström 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):717-720
Abstract Flow linear dichroism and fluorescence spectroscopy show that the covalent (+)-anti-BPDE-DNA complex adopts two rapidly interchanging conformations. The binding introduces local flexibility in DNA facilitating further covalent attacks. 相似文献
60.
Magdalena Pfister Silke Farkas Ramamurthy Charubala Wolfgang Pfleiderer 《Nucleosides, nucleotides & nucleic acids》2013,32(5-6):595-600
Abstract The usefulness of the p-nitrophenylethylsulfonyl (NPES) group for 2′-OH protection in oligoribonucleotide synthesis is further investigated. The difficulties of uridine protection are discussed and the p-cyanophenylethyl (CPE) group introduced as a versatile new 04-blocking group. 相似文献