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61.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.62.
63.
Role of histone H3 lysine 27 methylation in X inactivation 总被引:1,自引:0,他引:1
Plath K Fang J Mlynarczyk-Evans SK Cao R Worringer KA Wang H de la Cruz CC Otte AP Panning B Zhang Y 《Science (New York, N.Y.)》2003,300(5616):131-135
The Polycomb group (PcG) protein Eed is implicated in regulation of imprinted X-chromosome inactivation in extraembryonic cells but not of random X inactivation in embryonic cells. The Drosophila homolog of the Eed-Ezh2 PcG protein complex achieves gene silencing through methylation of histone H3 on lysine 27 (H3-K27), which suggests a role for H3-K27 methylation in imprinted X inactivation. Here we demonstrate that transient recruitment of the Eed-Ezh2 complex to the inactive X chromosome (Xi) occurs during initiation of X inactivation in both extraembryonic and embryonic cells and is accompanied by H3-K27 methylation. Recruitment of the complex and methylation on the Xi depend on Xist RNA but are independent of its silencing function. Together, our results suggest a role for Eed-Ezh2-mediated H3-K27 methylation during initiation of both imprinted and random X inactivation and demonstrate that H3-K27 methylation is not sufficient for silencing of the Xi. 相似文献
64.
65.
Dorota Miliszkiewicz Piotr Wieczorek Barbara Lejczak Ewa Kowalik Pawel Kafarski 《Pest management science》1992,34(4):349-354
Phosphonic and phosphinic acid analogues of glutamic and aspartic acids were synthesized and screened for herbicidal activity on Lepidium sativum L. Depending on the chemical structure, they exhibited significant or moderate herbicidal activity against L. sativum roots (with some representatives being equipotent with phosphinothricin), while their influence on shoot growth was negligible. Cucumis sativus L. appeared to be more tolerant to these analogues. The origin of this selectivity remains to be determined. 相似文献
66.
Giuseppina Chianese Ernesto Fattorusso Masteria Yunovilsa Putra Barbara Calcinai Giorgio Bavestrello Aniello Schiano Moriello Luciano De Petrocellis Vincenzo Di Marzo Orazio Taglialatela-Scafati 《Marine drugs》2012,10(11):2435-2447
Leucettamols, bifunctionalized sphingoid-like compounds obtained from a marine sponge Leucetta sp., act as non-electrophilic activators of the TRPA1 channel and potent inhibitors of the icilin-mediated activation of the TRPM8 channel, while they are inactive on CB1, CB2 and TRPV1 receptors. Leucettamols represent the first compounds of marine origin to target TRPA1 and the first class of natural products to inhibit TRPM8 channels. The preparation of a small series of semi-synthetic derivatives revealed interesting details on the structure-activity relationships within this new chemotype of simple acyclic TRP modulators. 相似文献
67.
T. T. Chen L. B. Agellon C. M. Lin H. J. Tsai Peijun Zhang L. I. González-Villasénor D. A. Powers 《Fish physiology and biochemistry》1989,7(1-6):381-385
The primary structures of two rainbow trout growth hormone mRNAs (GH1 and GH2) have been deduced by direct sequencing of their
respective cDNA clones and portions of the mRNA. Both GH1 and GH2 mRNA contain open reading frames comprised of 630 nucleotides
and encode 210 amino acid residues of which 11 are variant. The translated regions of both mRNA are flanked by a short but
rather conserved 5′-end, and a relatively long but highly diverged 3′-end. The differences at translated and 3′-untranslated
regions suggest that the GH1 and GH2 mRNA originate from different loci. The GH1 and GH2 mRNA are likely transcribed from
two distinct loci which were duplicated during tetraploidization of salmonid genome between 50 to 100 million years ago.
The GH2 gene has been isolated and sequenced from a rainbow trout genomic library. This gene spans a region of approximately
4 kilobases. The trout GH gene is comprised of 6 exons and 5 introns, in contrast to 5 exons and 4 introns in mammals. The
additional intron in the trout gene interrupts the translated regions that are analogous to the last exon of the mammalian
counterpart. The alleged internally repeating sequences in mammalian GH, prolactin (Pr1) and placental lactogen (PL) are not
observed in the predicted polypeptide sequence of trout GH. In addition, direct repeats that flank exons I, III and V of mammalian
GH, Pr1 and PL genes are absent in trout gene. These findings indicate that the rainbow trout GH gene structure does not support
the current hypothesis that internally repeated regions in GH, Pr1 and PL arose from a small primordial gene. 相似文献
68.
Oliver SP Almeida RA Gillespie BE Ivey SJ Moorehead H Lunn P Dowlen HH Johnson DL Lamar KC 《Veterinary therapeutics : research in applied veterinary medicine》2003,4(3):299-308
Streptococcus uberis is an important cause of mastitis in dairy cows throughout the world, particularly during the dry period, around the time of calving, and during early lactation. Strategies for controlling S. uberis mastitis have not received adequate research attention and are therefore poorly defined and inadequate. Objectives of the present study were to evaluate the efficacy of extended therapy regimens with pirlimycin for treatment of experimentally induced S. uberis intramammary infections in lactating dairy cows during early lactation and to evaluate the usefulness of the S. uberis experimental infection model for evaluating antimicrobial efficacy in dairy cows. The efficacy of extended pirlimycin intramammary therapy regimens was investigated in 103 mammary glands of 68 dairy cows that became infected following experimental challenge with S. uberis during early lactation. Cows infected with S. uberis in one or both experimentally challenged mammary glands were randomly allocated to three groups, representing three different treatment regimens with pirlimycin, including 2-day (n = 21 cows, 31 mammary quarters), 5-day (n = 21 cows, 32 quarters), and 8-day (n = 26 cows, 40 quarters). For all groups, pirlimycin was administered at a rate of 50 mg of pirlimycin hydrochloride via intramammary infusion. A cure was defined as an experimentally infected mammary gland that was treated with pirlimycin and was bacteriologically negative for the presence of S. uberis at 7, 14, 21, and 28 days after treatment. Experimental S. uberis intramammary infections were eliminated in 58.1% of the infected quarters treated with the pirlimycin 2-day regimen, 68.8% for the 5-day regimen, and 80.0% for the 8-day regimen. Significant differences (P <.05) in efficacy were observed between the 2-day and 8-day treatment regimens. The number of somatic cells in milk decreased significantly following therapy in quarters for which treatment was successful in eliminating S. uberis. However, there was no evidence to suggest that extended therapy with pirlimycin resulted in a greater reduction in somatic cell counts in milk than the 2-day treatment. The S. uberis experimental infection model was a rapid and effective means of evaluating antimicrobial efficacy during early lactation at a time when mammary glands are highly susceptible to S. uberis intramammary infection. 相似文献
69.
70.
First morphological characterization of 'Candidatus Mycoplasma turicensis' using electron microscopy
Willi B Museux K Novacco M Schraner EM Wild P Groebel K Ziegler U Wolf-Jäckel GA Kessler Y Geret C Tasker S Lutz H Hofmann-Lehmann R 《Veterinary microbiology》2011,149(3-4):367-373
At least three haemotropic mycoplasmas have been recognized in cats: Mycoplasma haemofelis (Mhf), 'Candidatus Mycoplasma haemominutum' (CMhm) and 'Candidatus M. turicensis' (CMt). The latter was originally identified in a Swiss pet cat with haemolytic anaemia and shown to be prevalent in domestic cats and wild felids worldwide using molecular methods. So far, there has been no confirmatory morphological evidence of the existence of CMt presumably due to low blood loads during infection while CMhm has only been characterized by light microscopy with discrepant results. This study aimed to provide for the first time electron microscopic characteristics of CMt and CMhm and to compare them to Mhf. Blood samples from cats experimentally infected with CMt, CMhm and Mhf were used to determine copy numbers in blood by real-time PCR and for transmission and scanning electron microscopy. High resolution scanning electron microscopy revealed CMt and CMhm to be discoid-shaped organisms of 0.3 μm in diameter attached to red blood cells (RBCs). In transmission electron microscopy of CMt, an oval organism of about 0.25 μm with several intracellular electron dense structures was identified close to the surface of a RBC. CMhm and CMt exhibited similar morphology to Mhf but had a smaller diameter. This is the first study to provide morphological evidence of CMt thereby confirming its status as a distinct haemoplasma species, and to present electron microscopic features of CMhm. 相似文献