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51.
Alicja Stach 《Aerobiologia》2000,16(1):63-68
The airborne pollen concentration of the four mostfrequent and most allergenic taxa in Poland; Alnus, Betula, Poaceae, and Artemisia atPozna in the years 1995–1996 has been analyzed,using a Hirst-type volumetric spore trap. Theappearance of the earliest pollen producing taxa wasobserved as early as January and February, which isrelevant information for people subject to allergiesin the Pozna region, where Spring usually beginsin March. The periods of high and very high pollenconcentration of individual taxa have been comparedfor the two years. 相似文献
52.
Molecular Mechanism of Heat Shock-Provoked Disassembly of the Coliphage λ Replication Complex 下载免费PDF全文
Alicja Wgrzyn Anna Herman-Antosiewicz Karol Taylor Grzegorz Wgrzyn 《Journal of bacteriology》1998,180(9):2475-2483
We have found previously that, in contrast to the free O initiator protein of λ phage or plasmid rapidly degraded by the Escherichia coli ClpP/ClpX protease, the λO present in the replication complex (RC) is protected from proteolysis. However, in cells growing in a complete medium, a temperature shift from 30 to 43°C resulted in the decay of the λO fraction, which indicated disassembly of RC. This process occurred due to heat shock induction of the groE operon, coding for molecular chaperones of the Hsp60 system. Here we demonstrate that an increase in the cellular concentration of GroEL and GroES proteins is not in itself sufficient to cause RC disassembly. Another requirement is a DNA gyrase-mediated negative resupercoiling of λ plasmid DNA, which counteracts DNA relaxation and starts to dominate 10 min after the temperature upshift. We presume that RC dissociates from λ DNA during the negative resupercoiling, becoming susceptible to the subsequent action of GroEL/S and ClpP/ClpX proteins. In contrast to λcro+, in λcro− plasmid-harboring cells, the RC reveals heat shock resistance. After temperature upshift of the λcrots plasmid-harboring cells, a Cro repressor-independent control of λ DNA replication and heat shock resistance of RC are established before the period of DNA gyrase-mediated negative supercoiling. We suggest that the tight binding of RC to λ DNA is due to interaction of RC with other DNA-bound proteins, and is related to the molecular basis of the λcro− plasmid replication control. 相似文献
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Marzena Rams-Baron Mateusz Dulski Anna Mrozek-Wilczkiewicz Mateusz Korzec Wioleta Cieslik Ewelina Spaczyńska Piotr Bartczak Alicja Ratuszna Jaroslaw Polanski Robert Musiol 《PloS one》2015,10(6)
New styrylquinoline derivatives with their photophysical constants are described. The synthesis was achieved via Sonogashira coupling using the newly developed heterogeneous nano-Pd/Cu catalyst system, which provides an efficient synthesis of high purity products. The compounds were tested in preliminary fluorescent microscopy studies to in order to identify their preferable cellular localization, which appeared to be in the lipid cellular organelles. The spectroscopic properties of the compounds were measured and theoretical TD-DFT calculations were performed. A biological analysis of the quinolines that were tested consisted of cytotoxicity assays against normal human fibroblasts and colon adenocarcinoma cells. All of the compounds that were studied appeared to be safe and indifferent to cells in a high concentration range. The presented results suggest that the quinoline compounds that were investigated in this study may be valuable structures for development as fluorescent dyes that could have biological applications. 相似文献
54.
Barbara Alicja Jereczek-Fossa Sara Ronchi Roberto Orecchia 《Reports of Practical Oncology and Radiotherapy》2015,20(6):472-483
ObjectivesTo review the available data about stereotactic body-radiotherapy (SBRT) for oligometastatic lymph node cancer recurrence.MethodsThe inclusion criteria for this study were as follows: Medline search for the (1) English language (2) full paper (abstracts were excluded) on (3) adult oligometastatic solid cancer recurrence limited to lymph node that underwent SBRT (4) outcome data available and (5) published up to the 30th April 2014.Results38 papers fulfilling the inclusion criteria have been found: 7 review articles and 31 patient series (20 and 11 retrospective and prospective studies, respectively) including between 1 and 69 patients (636 lymph nodes). Twelve articles reported only lymph node SBRT while in 19 – all types of SBRT including lymph node SBRT were presented. Two-year local control, 4-year progression free survival and overall survival was of up to 100%, 30% and 50%, respectively. The progression was mainly out-field (10–30% of patients had a recurrence in another lymph node/nodes). The toxicity was low with mainly mild acute events and single grade 3–4 late events. When compared to SBRT for any oligometastatic cancer, SBRT for lymph node recurrence carried better prognosis and showed lower toxicity.ConclusionsSBRT is a feasible approach for oligometastatic lymph node recurrence, offering excellent in-field tumor control with low toxicity profile. The potential abscopal effect has been hypothesized as a basis of these findings. Future studies are warranted to identify the patients that benefit most from this treatment. The optimal combination with systemic treatment should also be defined. 相似文献
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Alicja. J. Copik Aleksander Baldys Khanh Nguyen Sunil Sahdeo Hoangdung Ho Alan Kosaka Paul J. Dietrich Bill Fitch John R. Raymond Anthony P. D. W. Ford Donald Button Marcos E. Milla 《PloS one》2015,10(1)
The α1A-AR is thought to couple predominantly to the Gαq/PLC pathway and lead to phosphoinositide hydrolysis and calcium mobilization, although certain agonists acting at this receptor have been reported to trigger activation of arachidonic acid formation and MAPK pathways. For several G protein-coupled receptors (GPCRs) agonists can manifest a bias for activation of particular effector signaling output, i.e. not all agonists of a given GPCR generate responses through utilization of the same signaling cascade(s). Previous work with Gαq coupling-defective variants of α1A-AR, as well as a combination of Ca2+ channel blockers, uncovered cross-talk between α1A-AR and β2-AR that leads to potentiation of a Gαq-independent signaling cascade in response to α1A-AR activation. We hypothesized that molecules exist that act as biased agonists to selectively activate this pathway. In this report, isoproterenol (Iso), typically viewed as β-AR-selective agonist, was examined with respect to activation of α1A-AR. α1A-AR selective antagonists were used to specifically block Iso evoked signaling in different cellular backgrounds and confirm its action at α1A-AR. Iso induced signaling at α1A-AR was further interrogated by probing steps along the Gαq /PLC, Gαs and MAPK/ERK pathways. In HEK-293/EBNA cells transiently transduced with α1A-AR, and CHO_α1A-AR stable cells, Iso evoked low potency ERK activity as well as Ca2+ mobilization that could be blocked by α1A-AR selective antagonists. The kinetics of Iso induced Ca2+ transients differed from typical Gαq- mediated Ca2+ mobilization, lacking both the fast IP3R mediated response and the sustained phase of Ca2+ re-entry. Moreover, no inositol phosphate (IP) accumulation could be detected in either cell line after stimulation with Iso, but activation was accompanied by receptor internalization. Data are presented that indicate that Iso represents a novel type of α1A-AR partial agonist with signaling bias toward MAPK/ERK signaling cascade that is likely independent of coupling to Gαq. 相似文献
57.
Michael R. Perkin Tara Bader Alicja R. Rudnicka David P. Strachan Christopher G. Owen 《PloS one》2015,10(11)
Objective
Allergic conjunctivitis (AC) is a common condition, especially in childhood. The extent to which it occurs concurrently with or independently from allergic rhinitis (AR) has not been well described.Aim
To examine the inter-relationship between rhinitis and conjunctivitis and the epidemiological risk factors for these conditions in a rural UK population.Methods
Cross-sectional study of rural school children (aged 5–11 years). Parental questionnaires were used to diagnose allergic outcomes (including conjunctivitis, rhinitis and rhinoconjunctivitis), and to collect data on atopic history, demographic and environmental exposures. Odds ratios of allergic outcome by exposure were examined adjusted for age, sex, breastfeeding, family history of allergy, number of older and younger siblings.Results
Prevalence of conjunctivitis was 17.5%, rhinitis 15.1% and rhinoconjunctivitis 13.0%. Seasonality of symptoms varied by condition: 64.7% of those with conjunctivitis had seasonal symptoms (April-Sept only), 46.7% of those with rhinitis and 92.2% of those with rhinoconjunctivitis. Living on a farm consistently reduced the risk of conjunctivitis (odds ratio 0.47, 95%CI 0.29–0.79, p = 0.004), rhinitis (OR 0.57, 95%CI 0.33–1.01, p = 0.05) and rhinoconjunctivitis (OR 0.57, 95%CI 0.32–1.03, p = 0.06). Exposure to farm animals (particularly in early life), current consumption of unpasteurised milk and playing in a barn or stable significantly reduced the risk of all three conditions.Conclusion
More children had parent-reported conjunctivitis than rhinitis. The majority of children with either condition also reported symptoms with the other condition. Farmers’ children have less eye and/or nasal symptoms. A number of farming variables linked with the farm microbial environment are likely to be mediating the protective effect. 相似文献58.
Jacek Wierzchowski Alicja Stachelska-Wierzchowska Beata Wielgus-Kutrowska Goran Mikleušević 《Analytical biochemistry》2014
Two nontypical nucleosides, 7-β-d-ribosyl-2,6-diamino-8-azapurine and 8-β-d-ribosyl-2,6-diamino-8-azapurine, have been found to exhibit moderately good, and selective, substrate properties toward calf and bacterial (Escherichia coli) forms of purine nucleoside phosphorylase (PNP). The former compound is effectively phosphorolysed by calf PNP and the latter by PNP from E. coli. Both compounds are fluorescent with λmax ∼ 425 to 430 nm, but the reaction product, 2,6-diamino-8-azapurine, emits in a different spectral region (λmax ∼ 363 nm) with nearly 40% yield, providing a strong fluorogenic effect at 350 to 360 nm. 相似文献
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60.
Robert Rutkowski Łukasz Rejt Anna Tereba Alicja Gryczyńska-Siemiątkowska Bartosz Janic 《European Journal of Wildlife Research》2010,56(3):297-305
We analysed the genetic structure of the European kestrel population of Central Poland using nine highly polymorphic microsatellite loci. Samples were collected in two urban locations (Warsaw and ?ód?) and two rural areas. Sampling locations were at nearly equal distances from each other along an east to west line. We performed genotyping in a total of 99 birds. The results revealed the presence of a genetic structure in the population investigated. Bayesian clustering indicated that samples originated from more than one population. Genetic differentiation was less pronounced among the birds nesting in Warsaw and in the two rural sites, whereas all pairwise comparisons with the ?ód? population indicated moderate and significant genetic differentiation. The observed pattern of differentiation might have been caused by two factors: changes in allele frequency between seasons and/or the founding of the urban population of ?ód? from a different source population than the urban population from Warsaw. Additionally, we found a rather high gene flow among kestrels from the Warsaw urban area and the two investigated rural areas. 相似文献