Search results for "Betula"
showing 10 items of 71 documents
Parental hay fever reinforces IgE to pollen as pre-clinical biomarker of hay fever in childhood
2014
An early IgE response to grass or birch pollen can anticipate seasonal allergic rhinitis to pollen later in life or remain clinically silent.To identify risk factors early in life that allow discriminating pathogenic from non-pathogenic IgE responses and contribute to the development of seasonal allergic rhinitis to grass pollen.The German Multicentre Allergy Study examined a birth cohort born in 1990. A questionnaire was yearly administered and blood samples collected at age 1,2,3,5,6,7,10,13 yr. The definition of the primary outcome grass- and birch-pollen-related seasonal allergic rhinitis (SARg, SARb) was based on nasal symptoms in June/July and April, respectively. Serum IgE antibodies…
Quality and potency profile of eight recombinant isoallergens, largely mimicking total Bet v 1-specific IgE binding of birch pollen.
2019
Background To date, only limited information on structure, expression levels and IgE binding of Bet v 1 variants, which are simultaneously expressed in birch pollen, is available. Objective To analyse and compare structure and serum IgE/IgG binding of rBet v 1 variants to Bet v 1.0101. Methods Recombinant Bet v 1 variants were studied with sera of 20 subjects allergic to birch pollen. Folding, aggregation and solubility of the rBet v 1 variants were analysed to attribute diverging IgE binding to either allergen structure or methodological features. IgE/IgG binding was studied with rBet v 1 in solution or adsorbed to solid phases. Allergen-mediated cross-linking of FceRI receptors was determ…
Carboxymethylation of alkali extracted xylan for preparation of bio-based packaging films
2012
This study describes the synthesis of carboxymethylxylan (CMX) and investigates its suitability as a film for packaging applications. High-purity polymeric xylan was extracted from commercial bleached birch kraft pulp and converted to CMX with three different degrees of substitution (DSs). The water vapor sorption, mechanical, and barrier properties of the films prepared from CMX were tested. Increasing DS of CMX films resulted in an increase in elongation at break and a decrease in tensile strength and Young's modulus. The DS also affected the barrier properties of the films. CMX films with higher DS showed improved (reduced) oxygen permeability (OP), and the water vapor permeability (WVP)…
Characterization of lignin dissolved during alkaline pretreatment of softwood and hardwood
2015
Various alkaline pretreatments were applied to Scots pine (Pinus sylvestris) and silver/white birch (Betula pendula/pubescens) wood chips and the characterization of sulfur-free lignin dissolved was performed. The behavior of lignin during these pretreatments (alkali charge 1–8% NaOH, time 30–120 minutes, and temperature 130–150°C) was studied mainly in terms of lignin removal efficiency and molar mass distribution of dissolved lignin. The amount of lignin in pretreatment liquors increased along with an increase in the alkali charge of 0.8–4.4% and 0.6–3.4% of o.d. pine and birch wood, respectively. The most significant parameter affecting the molar mass of the dissolved lignin was shown to…
The Root Mycobiota of Betula aetnensis Raf., an Endemic Tree Species Colonizing the Lavas of Mt. Etna (Italy)
2021
Betula aetnensis is an endemic tree of high conservation value, which thrives on the nutrient-poor volcanic soils of Mount Etna. Since plant–microbe interactions could play a crucial role in plant growth, resource uptake, and resistance to abiotic stresses, we aimed to characterize the root and rhizosphere microbial communities. Individuals from natural habitat (NAT) and forest nursery (NURS) were surveyed through microscopy observations and molecular tools: bacterial and fungal automated ribosomal intergenic spacer analysis (ARISA), fungal denaturing gradient gel electrophoresis (DGGE). B. aetnensis was found to be simultaneously colonized by arbuscular (AM), ectomycorrhizal (ECM), ericoid…
Quantitative DNA Analyses for Airborne Birch Pollen
2015
Birch trees produce large amounts of highly allergenic pollen grains that are distributed by wind and impact human health by causing seasonal hay fever, pollen-related asthma, and other allergic diseases. Traditionally, pollen forecasts are based on conventional microscopic counting techniques that are labor-intensive and limited in the reliable identification of species. Molecular biological techniques provide an alternative approach that is less labor-intensive and enables identification of any species by its genetic fingerprint. A particularly promising method is quantitative Real-Time polymerase chain reaction (qPCR), which can be used to determine the number of DNA copies and thus poll…
Assessment of the possibility of using deciduous tree bark as a biomonitor of heavy metal pollution of atmospheric aerosol
2019
The aim of the research was to assess the possibility to use deciduous tree bark in the biomonitoring of urban areas. The tree bark taken from various deciduous tree species growing in the Opole Province (south-western Poland) was used for the research. The bark was collected from tree trunks in the period of June 2–26, 2017. Concentrations of the heavy metals were determined in the barks by flame atomic absorption spectrometry (FAAS). On the basis of the research, it was determined that type of tree, distance from pollution source, elevation off the ground and the side of trunk from which bark was sampled all influence the research results. A comparison of the values of coefficient of vari…
High diversity of root endophytes in the pioneer endemic Betula aetnensis Raf. colonizing volcanic lavas
2019
Introduction Betula aetnensis Raf. is an endemic tree species native to Sicily of particular conservation value, that establishes on nutrient-poor and water-limited lava of Etna volcano. In these harsh conditions plant-microbe interactions could play a crucial role in plant growth, resource uptake and resistance to abiotic stresses. The aim of this study is to investigate the root-associated microbial community of B. aetnensis growing in its natural habitat. The comparison between individuals from natural habitats and nursery-grown seedlings aims to assess the symbiotic status of plant material used for afforestation purposes. Materials and Methods Betula aetnensis individuals were collecte…
Alnus glutinosa (L.) Gaertn. and Alnus cordata (Loisel) Duby as new sources of safe cosmetic and pharmacological anti-melanogenic agents
2018
The genus Alnus (Betulaceae) comprises many species with a long history in traditional medicines. The crude extracts and isolated compounds from Alnus species exhibit a wide spectrum of in vitro and in vivo pharmacological activities (1). Phytochemical investigations revealed the presence of diarylheptanoids, a class of natural products typically found in Alnus genus with two aryl groups joined by a heptane chain in the main skeleton that have drawn attention due to their multiple biological properties and their therapeutic potential (2). A previous study reported that oregonin and other structurally analogous diarylheptanoids isolated from the bark of A. hirsuta showed inhibitory effects o…
Airborne birch pollen in Poland and Latvia in the light of data obtained from aerobiological monitoring and tauber traps in relation to mean air temp…
2012
Birch pollen contains allergens belonging to those with the strongest allergenic properties. In order to trace pollen season patterns of this taxon and pollen annual sums at a wider regional scale, cooperation was established with the University of Latvia in Riga (Latvia). A comparison of the results obtained in the years 2003-2008 in Lublin and in Riga, using volumetric samplers, shows that there was a similar trend in the abundance of birch pollen. The highest sums were noted at both sites in 2003. In all the study years, more birch pollen grains were recorded in Lublin than in Riga, on the average by 7110. The birch pollen seasons started earlier in Lublin than in Riga, on the average by…