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PubMed1999

[Pharmacological and clinical effectiveness of a fixed phytogenic combination trembling poplar (Populus tremula), true goldenrod (Solidago virgaurea) and ash (Fraxinus excelsior) in mild to moderate rheumatic complaints].

Besides the well-known nonsteroidal antiinflammatory drugs (NSAID) for the treatment of rheumatic pain herbal medicine can also be applied successfully. Plants with antirheumatic efficacy include Fraxini cortex, Populi cortex/folia and Solidaginis herba. This review focuses on pharmacological and clinical efficacy of a combination of Fraxinus cortex, Populus cortex/folia and Solidago herba. Antiinflammatory and analgetic properties were shown in pharmacological tests. Clinical studies conducted in the indications of the different subtypes of rheumatic diseases such as rheumatoid arthritis or osteoarthritis pointed out a similar efficacy compared to NSAID applied in average dosages. Even the rate of adverse effects of the herbal combination was half of that registered in NSAID treated patients within the clinical studies.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2000

Microsatellite DNA markers in Populus tremuloides.

Markers for eight new microsatellite DNA or simple sequence repeat (SSR) loci were developed and characterized in trembling aspen (Populus tremuloides) from a partial genomic library. Informativeness of these microsatellite DNA markers was examined by determining polymorphisms in 38 P. tremuloides individuals. Inheritance of selected markers was tested in progenies of controlled crosses. Six characterized SSR loci were of dinucleotide repeats (two perfect and four imperfect), and one each of trinucleotide and tetranucleotide repeats. The monomorphic SSR locus (PTR15) was of a compound imperfect dinucleotide repeat. The primers of one highly polymorphic SSR locus (PTR7) amplified two loci, and alleles could not be assigned to a specific locus. At the other six polymorphic loci, 25 alleles were detected in 38 P. tremuloides individuals; the number of alleles ranged from 2 to 7, with an average of 4.2 alleles per locus, and the observed heterozygosity ranged from 0.05 to 0.61, with an average of 0.36 per locus. The two perfect dinucleotide and one trinucleotide microsatellite DNA loci were the most informative. Microsatellite DNA variants of four SSR loci characterized previously followed a single-locus Mendelian inheritance pattern, whereas those of PTR7 from the present study showed a two-locus Mendelian inheritance pattern in controlled crosses. The microsatellite DNA markers developed and reported here could be used for assisting various genetic, breeding, biotechnology, genome mapping, conservation, and sustainable forest management programs in poplars.

Alleles↗
PubMed2000

Anthocyanin, bisabolol and phenylammonialyase activity in cell cultures of Populus deltoides.

Phenolics, anthocyanin and alpha-bisabolol production from poplar (Populus delotides) in tissue culture was determined. A number of phenolic acids were identified by HPLC. PAL activity in response to phytohormones, cells growth and anthocyanin production showed a positive correlation. A component, alpha-bisabolol, was identified using gas chromatography and UV spectroscopy. In vitro production of said metabolites was influenced by phytohormones.

Ammonia-Lyases↗
PubMed2001

Phytotoxicity of chlorinated aliphatics to hybrid poplar (Populus deltoides x nigra DN34).

Effects of a series of chlorinated ethenes and ethanes on hybrid poplar (Populus deltoides x nigra DN34) were assessed in laboratory experiments. Poplar cuttings were grown in sealed reactors with hydroponic solutions and were exposed to a chlorinated solvent for a period of two weeks. Exposure concentrations ranged from 0 to 0.4 mM for perchloroethylene to 0 to 8.4 mM for 1,1-dichloroethane. Effects were assessed by gravimetrically monitoring transpiration and measuring change in cutting mass. The zero-growth concentrations of the chemicals tested were 0.3 mM perchloroethylene, 0.9 mM trichloroethylene, 0.9 mM 1,1,2,2-tetrachloroethane, 2.0 mM 1,1,1-trichloroethane, 2.3 mM 1,1,2-trichloroethane, 4.8 mM trans-dichloroethylene, 5.6 mM 1,1-dichloroethylene, 6.0 mM cis-dichloroethylene, and 10.7 mM 1,1-dichloroethane. Adverse effects were found to increase with increasing number of chlorine atoms within a homologous series of ethenes or ethanes. Ethenes were more toxic than similarly chlorinated ethanes.

Biomass↗
PubMed2000

Diurnal regulation of plastid genes in Populus deltoides.

Light regulates leaf and chloroplast development, together with overall chloroplast gene expression at various levels. Plants respond to diurnal and seasonal changes in light by changing expression of photosynthesis genes and metabolism. In Populus deltoides, a deciduous tree species, leaf development begins in the month of March and leaf maturation is attained by summer, which is subsequently followed by autumnal senescence and fall. In the present study, diurnal changes in the steady state transcript levels of plastid genes were examined in the fully developed leaves during summer season. Our results show that steady state level of the psaA/B, psbA, psbEFLJ and petA transcripts showed differential accumulation during diurnal cycle in summer. However, there was no significant change in the pigment composition during the day/night cycle. Our studies suggest that the diurnal regulation of steady state mRNA accumulation may play a crucial role during daily adjustments in plants life with rapidly changing light irradiance and temperature.

Circadian Rhythm↗
PubMed2001

Preliminary interspecific genetic maps of the populus genome constructed from RAPD markers.

We have constructed RAPD-based linkage maps for an interspecific cross between two species of the genus Populus (P. adenopoda and P. alba), based on a double pseudo-test-cross strategy. Of a total of 360 polymorphic fragments scored, 290 showed a test-cross configuration, corresponding to DNA polymorphisms heterozygous in one parent and null in the other. In the female parent, P. adenopoda, 82 markers were grouped in 19 different linkage groups (553 cM), whereas in the male parent P. alba, 197 markers established a much more complete framework map with an observed genome length of 2300 cM covering 87% of the total P. alba genome. The larger number of test-cross markers detected for the P. alba parent than for the P. adenopoda parent might be due to a higher level of heterozygosity in the former than in the latter. In this study, we detected only a small percentage (2%) of the intercross dominant markers heterozygous in both parents and segregating 3:1 in the progeny. The further focus in this mapping study should be on the identification of more intercross markers, to align the two parent-specific maps into a consensus map for mapping important genes causing species differentiation during long evolutionary divergences.

Chromosome Mapping↗
PubMed2002

Betula and Populus pollen counts and meteorological conditions in Szczecin, Poland.

The aim of the study was to analyse a relationship between the meteorological conditions and the pollen counts of selected allergenic taxa (Betula spp., Populus spp.) in the air of Szczecin city (north western Poland) in 2001. Apart from the individual rhythm of plant pollination, weather conditions are considered the most important factors determining the dispersion and content of pollen in the air. The meteorological parameters analysed were the minimum, maximum and average values of air temperature, relative humidity, solar radiation and wind speed. The beginning and end of a season were established by the 98 % method. The concentration of birch pollen in the air in 2001 was very high, the pollen season started in the third decade of April and lasted till the 10 May. The highest airborne concentration of 3,712 grains in 1 m(3) per 24 h was noted at the beginning of May on a sunny day with strong wind, and air temperature above 20 degrees C. The concentration of poplar pollen in 2001 was low. The pollen season started from the beginning of April and lasted till the beginning of May. The maximum concentration of airborne poplar pollen of 222 grains in 1 m(3) per 24 h was observed in the third decade of April and was preceded by several days with low temperature (1- 2 degrees C), rain, snowfalls and strong wind. A positive and statistically significant correlation was found between the air temperature and the birch pollen concentration, while a similar but negative correlation was found for poplar pollen.

Poland↗
PubMed1992

Study of the anti-inflammatory activity of Populus tremula, Solidago virgaurea and Fraxinus excelsior.

Aqueous/alcoholic extracts of Populus tremula, Solidago virgaurea and Fraxinus excelsior (components of Phytodolor N) were tested individually and in 3 different combinations for anti-inflammatory activity using carrageenan induced edema and/or adjuvant induced arthritis of the rat paw. The tested combinations as well as the individual extracts significantly reduced the paw edema to varying degrees and also dose dependently inhibited the arthritic paw volume. The anti-inflammatory activity of the combinations was respectively comparable to the tested doses of diclofenac.

Animals↗
PubMed2003

[Evaluation of ecological services of Populus simonii forest on Heerqin sandy land].

The main ecological services of the sand-fixed forest are windbreak, soil erosion control, and atmospheric dust retention. In this paper, the ecological services of Populus simonii forest were assessed by simultaneous measurements of wind speeds, daily amount of soil surface wind erosion, and amount of atmospheric dust deposition at different observation sites located within and outside the forestland. The results showed that compared with the control site (mobile sand dune), the daily mean wind velocity at 2 m height was reduced by 18.3, 31.6, 66.1, 66.0, 62.3 and 45.2% for the observation sites over the distances of 6 and 3 H (H meant average tree height) from forest edge of the windward side, forest center, and observation sites over the distances of 0, 6 and 8 H from forest edge of the leeward side, respectively. The greatest reduction in daily mean wind velocity was occurred in both forest center and forest edge of the leeward side. There was a significant positive relationship between leaf area index of the forest and monthly declining index of mean wind speed. The monthly declining index of mean wind speed increased with increasing the forest leaf area index by a cubic function. The daily wind erosion rates of soil surface in observation sites at 6 and 3 H from forest edge of the windward side, forest center, and at 0, 6 and 8 H from forest edge of the leeward side were reduced by as much as 85.2%-99.9%, in comparison with the control site. The greatest reduction in daily wind erosion rate of soil surface occurred in forest edge of the leeward side, followed in decreasing order by forest center, 6 and 8 H from forest edge of the leeward side, 3 and 6 H from forest edge of the windward side. During the observation period, the daily mean dust deposition within the forestland was 13.2 kg.hm-2, compared with 9.9 kg.hm-2 outside the forestland, with a 33% increase. All these results suggested that the poplar forest played an important role in reducing damaging winds, controlling wind erosion, and improving the local environment through increasing atmospheric dust deposition.

Conservation of Natural Resources↗
PubMed1990

[Studies on triterpenoids of Populus yunnanensis Dode].

Three triterpenoids (I, II and III) were isolated from the roots of Populus yunnanensis Dode, which has been used as a folk remedy for the treatment of urinary tract infection and calculus in Yunnan Province. Compound I and III were identified as friedelin and 21 alpha-hydroxyfriedelan-3-one and compound II as 21 alpha-acetoxyfriedelan-3-one which is a new triterpenoid. 13C NMR data of II showed that the presence of an alpha-acetoxy group at C-21 does not affect the boat conformation of ring E similar to the results in the study of some other D:A-friedo-oleananes.

Drugs, Chinese Herbal↗
PubMed1995

A combination of Populus tremula, Solidago virgaurea and Fraxinus excelsior as an anti-inflammatory and antirheumatic drug. A short review.

Anti-inflammatory properties of Populus tremula are mainly deduced from its components, the well investigated salicylates. Solidago extracts have spasmolytic, antihypertensive and diuretic effects. Fraxinus excelsior itself has hardly been investigated, but its coumarin components proved to have a variety of pharmacological properties, i.e. inhibition of T-cell activation and of the arachidonic acid cascade. Phytodolor N (abbreviated as PD) is a combination of the above mentioned plants. Various in vitro and especially in vivo studies proved its anti-inflammatory and antirheumatic properties, often comparable to non-steroidal anti-inflammatories, but with little or no side effects.

Animals↗
PubMed1995

Inhibition of dihydrofolate reductase activity by alcoholic extracts from Fraxinus excelsior, Populus tremula and Solidago virgaurea.

Aqueous-ethanolic extracts of Fraxinus excelsior, Populus, tremula and Solidago virgaurea in a combination of 1: 3: 1 (v/v/v) are the components of the plant drug Phytodolor N (abbreviated as PD), which exhibits antipyretic, analgesic and antirheumatic activity. Similar to a broad variety of synthetic non-steroidal anti-inflammatories the mentioned plant extracts inhibit dihydrofolate reductase. The following concentrations as percentage in the test volumes represent the individual I50-values: F. excelsior = 0.26% (v/v); P. tremula = 0.46% (v/v) and S. virgaurea = 0.6% (v/v). The combined extracts in PD exhibit an I50 at 0.3% (v/v). Testing the activity of the water-soluble compounds of corresponding dry extracts, the activity of F. excelsior with an apparent I50-value of 0.008% (w/v) by far dominates the inhibitory overall effect of the combination (I50 = 0.014%, w/v).

Animals↗
PubMed1995

Antioxidative properties of alcoholic extracts from Fraxinus excelsior, Populus tremula and Solidago virgaurea.

Aqueous-ethanolic extracts from Fraxinus excelsior, Populus tremula and Solidago virgaurea inhibit biochemical model reactions representing inflammatory situations to various extents. These model reactions include xanthine oxidase, diaphorase in the presence of the autoxidizable quinone juglone, lipoxygenase and photodynamic reactions driven by riboflavin or rose bengal. The tested extracts are the components of the phytomedicine Phytodolor N (abbreviated as PD) which possesses antipyretic, analgesic, antiinflammatory and antirheumatic activity. Since several reactive oxygen species produced by the mentioned model systems are also involved in inflammatory processes, the beneficial activities of the complete drug may at least in part be due to the reported antioxidative functions of the individual components.

Animals↗
PubMed1993

Insect tolerance of transgenic Populus nigra plants transformed with Bacillus thuringiensis toxin gene.

Leaves and stem segments of Populus nigra were transformed with A. tumefaciens LBA4404 harboring a binary vector containing chimeric genes of NPT and 35S-omega-B.t. toxin-Nos. Nineteen regenerated kanamycin resistant plants were analyzed by DNA hybridization, out of which 10 were shown to be the candidates of transgenic plants. Insect tolerance tests showed that the transgenic plants were toxic to two lepidopteran pests, Lymantria dispar L. and Apocheimia cinerarius Erschoff. Based on the results of Southern blot of PCR products and the cluster analysis of their growth and insect resistance, three independent transgenic plants were selected, which were then propagated in the nursery field. This field test is currently in progress.

Agrobacterium tumefaciens↗
PubMed1993

[Studies on the chemical constituents of Populus tomentosa carr].

Populus tomentosa Carr. a Chinese folk medicine, has been used for treatment of arthritic disease. A new flavonoid(1), with molecular formula C30H26O12 was isolated from this plant along with four known compounds. They were identified as apigenin-7-O-(6"-O-p-coumaroyl)-beta-D-glucopyranoside (I), salicin (II), tremulodin (III), tremulacin (IV) and daucosterol (V) by the use of 1HNMR, 13CNMR and 1H-13C COSY spectroscopy.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2004

Annotation of a 95-kb Populus deltoides genomic sequence reveals a disease resistance gene cluster and novel class I and class II transposable elements.

Poplar has become a model system for functional genomics in woody plants. Here, we report the sequencing and annotation of the first large contiguous stretch of genomic sequence (95 kb) of poplar, corresponding to a bacterial artificial chromosome clone mapped 0.6 centiMorgan from the Melampsora larici-populina resistance locus. The annotation revealed 15 putative genetic objects, of which five were classified as hypothetical genes that were similar only with expressed sequence tags from poplar. Ten putative objects showed similarity with known genes, of which one was similar to a kinase. Three other objects corresponded to the toll/interleukin-1 receptor/nucleotide-binding site/leucine-rich repeat class of plant disease resistance genes, of which two were predicted to encode an amino terminal nuclear localization signal. Four objects were homologous to the Ty1/ copia family of class I transposable elements, one of which was designated Retropop and interrupted one of the disease resistance genes. Two other objects constituted a novel Spm-like class II transposable element, which we designated Magali.

Amino Acid Sequence↗