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451.
452.
Comparison of natural and recombinant forms of the major fish allergen parvalbumin from cod and carp
Ma Y Griesmeier U Susani M Radauer C Briza P Erler A Bublin M Alessandri S Himly M Vàzquez-Cortés S de Arellano IR Vassilopoulou E Saxoni-Papageorgiou P Knulst AC Fernández-Rivas M Hoffmann-Sommergruber K Breiteneder H 《Molecular nutrition & food research》2008,52(Z2):S196-S207
Allergic reaction following fish consumption can trigger life-threatening reactions in predisposed individuals. Parvalbumins from different species have been identified as the major fish allergens. There are two distinct phylogenetic lineages of parvalbumins, alpha and beta. Most allergic reactions are caused by beta-parvalbumins. We cloned and expressed cDNAs encoding cod (Gadus morhua) and carp (Cyprinus carpio) beta-parvalbumins and purified natural cod beta-parvalbumin. CD spectra of the purified proteins showed that their overall secondary structure contents were very similar. No differences in thermal stability were monitored in the calcium-bound or calcium-depleted form of natural cod parvalbumin. IgE reactivity was assessed using 26 sera of fish allergic patients from Spain, The Netherlands, and Greece in immunoblot and ELISA experiments. Twenty-five of the 26 patients with IgE reactivity to native and recombinant cod parvalbumin also reacted to the recombinant carp parvalbumin. IgE inhibition assays were performed using cod and carp extracts and purified recombinant parvalbumin of cod and carp. High crossreactivity among cod and carp parvalbumins was observed in immunoblots as well as in fluid phase assays. Natural and recombinant parvalbumins gave comparable results when performing various in vitro diagnostic assays. 相似文献
453.
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455.
Pia Michler Anne Schedel Martha Witschas Ulrike Anne Friedrich Rabea Wagener Juha Mehtonen Triantafyllia Brozou Maria Menzel Carolin Walter Dalileh Nabi Glen Pearce Miriam Erlacher Gudrun Ghring Martin Dugas Merja Heinniemi Arndt Borkhardt Friedrich Stlzel Julia Hauer Franziska Auer 《International journal of molecular sciences》2021,22(21)
While the shelterin complex guards and coordinates the mechanism of telomere regulation, deregulation of this process is tightly linked to malignant transformation and cancer. Here, we present the novel finding of a germline stop-gain variant (p.Q199*) in the shelterin complex gene POT1, which was identified in a child with acute myeloid leukemia. We show that the cells overexpressing the mutated POT1 display increased DNA damage and chromosomal instabilities compared to the wildtype counterpart. Protein and mRNA expression analyses in the primary patient cells further confirm that, physiologically, the variant leads to a nonfunctional POT1 allele in the patient. Subsequent telomere length measurements in the primary cells carrying heterozygous POT1 p.Q199* as well as POT1 knockdown AML cells revealed telomeric elongation as the main functional effect. These results show a connection between POT1 p.Q199* and telomeric dysregulation and highlight POT1 germline deficiency as a predisposition to myeloid malignancies in childhood. 相似文献
456.
Dr. Ulrike Schulz Peter Munzert Friedrich Rickelt Christiane Präfke Nancy Gratzke Heiko Knopf Sabrina Wolleb Prof. Dr. Norbert Kaiser 《真空研究与实践》2015,27(3):20-25
Inorganic‐organic hybrid coatings for antireflection of optical surfaces The application of nanostructures for optical surfaces has been discussed since antireflective nanostructures have been discovered on the eyes of night‐flying insects. On injection molded plastic lenses, antireflective nanostructures can easily be produced by plasma etching. The procedure has now been adapted to vacuum evaporated organic layers. Complex coatings composed of inorganic layers and organic nanostructures are especially suitable for realizing broadband antireflection properties on glass lenses. 相似文献
457.
Ulrike Wolf Roland Fuß Frank Höppner Heinz Flessa 《Nutrient Cycling in Agroecosystems》2014,100(1):121-134
Fertilization with biogas residues from the digestion of energy crops is of growing importance. Digestate from silage maize (Zea mays L.) is a new fertilizer with a high potential for ammonia (NH3) and nitrous oxide (N2O) emission. The aim of this study was to determine the effect of different maize fertilization systems [180 kg N ha?1 in form of calcium nitrate (MIN), biogas digestate from maize (DIG) and biogas digestate from maize mixed with the nitrification inhibitor Piadin (DIG + NI)] on the emission of NH3 and N2O from a sandy soil and to assess the total greenhouse gas emission of these fertilization systems. The study is based on a randomized field plot experiment in central Germany and an experimental period of a full year. Annual N2O-N emission was generally low [0.21 (MIN) to 0.37 (DIG) kg N ha?1] without differences between treatments. The application of Piadin reduced N2O emissions by 37 and 62 % during the weeks following digestate application but the annual N2O emission was not affected by the fertilization treatment. NH3 emission was only significant for treatments fertilized with digestate. It was not affected by Piadin and accounted for 27 % (+NI) and 29 % of the applied ammonium. Total greenhouse gas emission was dominated by NH3 losses (reducing the fertilizer value and inducing indirect N2O emissions) for the treatments fertilized with maize digestate. The most important greenhouse gas emission source of the MIN treatment were emissions from fertilizer production. Our results show the high potential of digestate from maize as a new source of NH3 emission. Mitigation measures are essential to save the value of this new fertilizer type and to reduce atmospheric and environmental pollution by direct emission of NH3 and indirect emission of greenhouse gases. 相似文献
458.
Ulrike Lyhs Janne Lahtinen Maria Fredriksson-Ahomaa Eija Hyyti-Trees Kai Elfing Hannu Korkeala 《International journal of food microbiology》2001,70(3):221-230
Microbiological and sensory changes of vacuum-packaged ‘gravad’ rainbow trout slices were studied during storage at 3 and 8 °C. At the time of spoilage, after 27 and 20 days of storage at 3 and 8 °C, respectively, both mesophilic viable counts (MVC) and psychrotrophic viable counts (PVC) reached 106–107cfu/g at 3 °C and 107–108 cfu/g at 8 °C. H2S-producing bacteria constituted a high proportion of the PVCs and lactic acid bacteria (LAB) counts were lower than the other determined bacterial counts. Sensory scores decreased with increasing MVC and PVC. The judges considered samples unfit for human consumption at MVC and PVC levels exceeding 106 and 107 cfu/g for samples stored at 3 and 8 °C, respectively. At respective levels of 107 and 108 cfu/g, most of the samples were deemed unfit. The main reasons for sensory rejection at both storage temperatures were the lack of the typical product odour or an ammonia off-odour and colour change to dark violet. The shelf-lives of the rainbow trout slices based on microbiological and sensory analyses were 20 days and 18 days at 3 and 8 °C, respectively. 相似文献
459.
The ability of many bacteria to adapt to stressful conditions may later protect them against the same type of stress (specific adaptive response) or different types of stresses (multiple adaptive response, also termed cross-protection). Arcobacter butzleri and Campylobacter jejuni are close phylogenetic relatives that occur in many foods of animal origin and have been linked with human illness (mainly diarrhoea). In the present study, sublethal stress adaptation temperatures (48 °C and 10 °C) and mild and lethal acid conditions (pH 5.0 and pH 4.0) were determined for A. butzleri and C. jejuni. In addition, it was evaluated whether these sublethal stress adaptations cause specific adaptive responses or cross-protection against subsequent mild or lethal acid stresses in these bacteria. The studies were conducted in broth adjusted to the different conditions and the results were determined by the dilution series plating method. It was shown that heat stress adapted A. butzleri (incubated for 2 h at 48 °C) were significantly more resistant to subsequent lethal acid stress (pH 4.0) than non-adapted cells at the 1 h time-point (p < 0.01 in Wilcoxon rank sum test). No specific adaptive responses against the stresses in A. butzleri or C. jejuni and no cross-protection in C. jejuni were found. The ability of heat stressed A. butzleri to tolerate later lethal acid conditions should be taken into account when designing new food decontamination and processing strategies. 相似文献
460.
A non-isothermal dynamic optimization model of direct methanol fuel cells (DMFCs) is developed to predict their performance with an effective optimum-operating strategy. After investigating the sensitivities of the transient behaviour (the outlet temperature, crossovers of methanol and water, and cell voltage) to operating conditions (the inlet flow rates into anode and cathode compartments, and feed concentration) through dynamic simulations, we find that anode feed concentration has a significantly larger impact on methanol crossover, temperature, and cell voltage than the anode and cathode flow rates. Also, optimum transient conditions to satisfy the desired fuel efficiency are obtained by dynamic optimization. In the developed model, the significant influence of temperature on DMFC behaviour is described in detail with successful estimation of its model parameters. 相似文献