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31.
Ole J Hamming Ewa Terczyńska‐Dyla Gabrielle Vieyres Ronald Dijkman Sanne E Jørgensen Hashaam Akhtar Piotr Siupka Thomas Pietschmann Volker Thiel Rune Hartmann 《The EMBO journal》2013,32(23):3055-3065
The IFNL4 gene is a recently discovered type III interferon, which in a significant fraction of the human population harbours a frameshift mutation abolishing the IFNλ4 ORF. The expression of IFNλ4 is correlated with both poor spontaneous clearance of hepatitis C virus (HCV) and poor response to treatment with type I interferon. Here, we show that the IFNL4 gene encodes an active type III interferon, named IFNλ4, which signals through the IFNλR1 and IL‐10R2 receptor chains. Recombinant IFNλ4 is antiviral against both HCV and coronaviruses at levels comparable to IFNλ3. However, the secretion of IFNλ4 is impaired compared to that of IFNλ3, and this impairment is not due to a weak signal peptide, which was previously believed. We found that IFNλ4 gets N‐linked glycosylated and that this glycosylation is required for secretion. Nevertheless, this glycosylation is not required for activity. Together, these findings result in the paradox that IFNλ4 is strongly antiviral but a disadvantage during HCV infection. 相似文献
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Ewa Rębacz-Maron Irena Baranowska-Bosiacka Izabela Gutowska Natalia Krzywania Dariusz Chlubek 《Biological trace element research》2013,156(1-3):91-95
The present study aimed at analysing the content of fluorine (F), calcium (Ca) and magnesium (Mg) in the hair of young male students (n?=?52) of a secondary school in Mafinga in Tanzania (Africa) who participated in anthropological examinations. Ca and Mg concentrations were determined using atomic absorption spectrophotometer while F levels using a potentiometric method. F in the hair of boys from older group (≥16 years old; n?=?24) was significantly higher than in the younger group (<16 years old; n?=?28) versus Ca and Mg levels. High carbohydrate diet was predominant—mainly based on corn or bean and meat served once a week, with few fruit and raw vegetables. Collective catering in the dormitory reflected habits and culinary preferences at home. The lack of balanced diet, with majority of the nutritional energy supplied by easily accessible and cheap carbohydrates, was reflected in dietary deficiencies, characterised, among others, by visible skin conditions and tooth decay. 相似文献
34.
Ewa Kaczorek Karolina Cieślak Katarzyna Bielicka-Daszkiewicz Andrzej Olszanowski 《Indian journal of microbiology》2013,53(1):84-91
Twelve different bacteria–yeast combinations were tested for determination of their ability to biodegrade diesel oil. The cell surface properties of the bacterial and yeast strains were correlated with the type of carbon source used in the experiments. The highest biodegradation of diesel oil after 7 days was obtained for the following combinations: Aeromonas hydrophila MR4–Yarrowia lipolytica EH 56 (87 %) and Xantomonas maltophila MRP7–Candida maltosa EH15 (90 %). Degradation performances of 10 of 12 combinations were enhanced by the presence of rhamnolipids. The highest increases were observed for A. hydrophila MR4–C. maltosa EH15 (from 34 to 67 %), A. hydrophila MR4–C. maltosa EH60 (from 47 to 76 %) and for Pseudomonas stutzeri MR7–C. maltosa EH60 (from 29 to 79 %). The addition of rhamnolipids to the system reduces the removal time of diesel oil from the contaminated water and changes the microbial adhesion to hydrocarbons. Modification of the cell surface of the tested strain during biodegradation is a very important factor determining the removal of hydrophobic compounds. 相似文献
35.
Ewa Grzebelus Maria Kruk Alicja Macko-Podgórni Dariusz Grzebelus 《Plant Cell, Tissue and Organ Culture》2013,115(2):209-222
Protoplasts isolated from three accessions of cultivated carrot and 5-day-old protoplast-derived aggregates were subjected to selection to identify somaclonal variants with enhanced tolerance to the fungal disease black rot incited by Alternaria radicina. Different concentrations [1, 2, 3.5, 5, 10, 20, 35 and 50 % (v/v)] of a fungal culture filtrate (FCF) from 2-week-old liquid cultures of A. radicina were used. Protoplasts and aggregates were subjected to short-term selection for a period of 10 days. All FCF concentrations added to the cultures on the day of isolation decreased protoplast survival frequency and plating efficiency, while FCF applied 5 days later inhibited cell divisions in 5–50 % concentrations. The responses of protoplasts to the treatment were genotype dependent. Most R0 plants were regenerated in all accessions from cell lines grown with 1 % FCF, while only a few plants were produced from 2 to 3.5 % FCF-treated cultures of ‘Dolanka’ and the breeding line ‘9304B’, respectively. Nineteen-percent of putative stress-tolerant regenerants were tetraploids, while only 5 % tetraploids were observed in the control. The incidence of unique random amplified polymorphic DNA fragments indicating possible chromosomal rearrangements was low and did not differ among regenerants after selection and those derived from the control. Mobilization of miniature inverted repeat transposable elements was not observed. Some R0 individuals regenerated both from FCF-treated and untreated cultures showed lower susceptibility to A. radicina in a laboratory assay in comparison to control plants grown from seed. Regenerants from FCF-treated cultures showed lower frequency of flowering plants and a higher rate of male sterility. Pollen viability of the putative stress-tolerant regenerants varied over a wide range (6–98 %), independently of in vitro selection conditions. Our data suggest that A. radicina FCF may be feasible for the in vitro selection to generate plants with superior phenotypic performance against A. radicina. 相似文献
36.
Hengshan Zhang Ane F. B. Zeidler Wei Song Christopher M. Puccia Ewa Malc Patricia W. Greenwell Piotr A. Mieczkowski Thomas D. Petes Juan Lucas Argueso 《Genetics》2013,193(3):785-801
The kinetochore is the macromolecular protein complex that mediates chromosome segregation. The Dsn1 component is crucial for kinetochore assembly and is phosphorylated by the Aurora B kinase. We found that Aurora B phosphorylation of Dsn1 promotes the interaction between outer and inner kinetochore proteins in budding yeast. 相似文献
37.
Barbara Pietrzak Anna Bednarska Magdalena Markowska Maciej Rojek Ewa Szymanska Miroslaw Slusarczyk 《Hydrobiologia》2013,715(1):125-134
The combined effect of external environment and energy allocation strategy of the organism on longevity can be exceptional. In a cold oligotrophic fishless habitat, individual Daphnia can live for over a year, several times the usual Daphnia lifespan. This extreme lifespan is in part a consequence of the overwintering strategy which includes storing resources and delaying reproduction until another spring. Yet, contrasting strategies may be applied by Daphnia, resulting in over twofold differences in lifespan within a single habitat. We identify physiological mechanisms mediating such differences in longevity in closely related Daphnia of two lineages coexisting within a high altitude lake, testing the predictions that long-lived animals stay in colder waters and have lower metabolic rates, irrespective of temperature. Vertical distribution of the animals was assessed during three summer stratification seasons, and metabolic activity was measured as oxygen consumption and RNA:DNA ratio. The results not only support our predictions but also reveal that habitat choice is dependent on reproductive status rather than genotype. The young individuals of the overwintering lineage may delay reproduction in part by staying in colder waters than the reproducing adults, which together with low intrinsic metabolic rates may underlie the longevity of Daphnia of this lineage. 相似文献
38.
Jadwiga Handzlik Ewa Szymańska Sandrine Alibert Jacqueline Chevalier Ewa Otrębska Elżbieta Pękala Jean-Marie Pagès Katarzyna Kieć-Kononowicz 《Bioorganic & medicinal chemistry》2013,21(1):135-145
A series of amine-alkyl derivatives of 5-arylidenehydantoin 3–21 was evaluated for their ability to improve antibiotic effectiveness in two strains of Gram-negative Enterobacter aerogenes: the reference strain (ATCC-13048) and the chloramphenicol-resistant derivative over-producing the AcrAB-TolC efflux pump (CM-64). Three antibiotics, chloramphenicol, nalidixic acid and sparfloxacin were used as markers of efflux pump activity. New compounds (5–16) were obtained within 3–4 step synthesis using Knoevenagel condensation, Mitsunobu reaction and microwave aided N-alkylation. Molecular modeling based structure–activity relationship (SAR) studies were performed. The most active compounds: (Z)-5-(4-(diethylamino)benzylidene)-3-(2-hydroxy-3-(4-(2-hydroxyethyl)piperazin-1-yl)propyl)imidazolidine-2,4-dione (14) and (Z)-5-(2,4-dimethoxybenzylidene)-3-(2-hydroxy-3-(isopropylamino)propyl)imidazolidine-2,4-dione (15) induced fourfold decrease of minimal inhibition concentration (MIC) of all tested antibiotics in the strain CM-64 overexpressing the AcrAB-TolC pump. 相似文献
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