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111.
Wolf population genetics in Europe: a systematic review,meta‐analysis and suggestions for conservation and management
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Maris Hindrikson Jaanus Remm Malgorzata Pilot Raquel Godinho Astrid Vik Stronen Laima Baltrūnaité Sylwia D. Czarnomska Jennifer A. Leonard Ettore Randi Carsten Nowak Mikael Åkesson José Vicente López‐Bao Francisco Álvares Luis Llaneza Jorge Echegaray Carles Vilà Janis Ozolins Dainis Rungis Jouni Aspi Ladislav Paule Tomaž Skrbinšek Urmas Saarma 《Biological reviews of the Cambridge Philosophical Society》2017,92(3):1601-1629
The grey wolf (Canis lupus) is an iconic large carnivore that has increasingly been recognized as an apex predator with intrinsic value and a keystone species. However, wolves have also long represented a primary source of human–carnivore conflict, which has led to long‐term persecution of wolves, resulting in a significant decrease in their numbers, genetic diversity and gene flow between populations. For more effective protection and management of wolf populations in Europe, robust scientific evidence is crucial. This review serves as an analytical summary of the main findings from wolf population genetic studies in Europe, covering major studies from the ‘pre‐genomic era’ and the first insights of the ‘genomics era’. We analyse, summarize and discuss findings derived from analyses of three compartments of the mammalian genome with different inheritance modes: maternal (mitochondrial DNA), paternal (Y chromosome) and biparental [autosomal microsatellites and single nucleotide polymorphisms (SNPs)]. To describe large‐scale trends and patterns of genetic variation in European wolf populations, we conducted a meta‐analysis based on the results of previous microsatellite studies and also included new data, covering all 19 European countries for which wolf genetic information is available: Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Germany, Belarus, Russia, Italy, Croatia, Bulgaria, Bosnia and Herzegovina, Greece, Spain and Portugal. We compared different indices of genetic diversity in wolf populations and found a significant spatial trend in heterozygosity across Europe from south‐west (lowest genetic diversity) to north‐east (highest). The range of spatial autocorrelation calculated on the basis of three characteristics of genetic diversity was 650?850 km, suggesting that the genetic diversity of a given wolf population can be influenced by populations up to 850 km away. As an important outcome of this synthesis, we discuss the most pressing issues threatening wolf populations in Europe, highlight important gaps in current knowledge, suggest solutions to overcome these limitations, and provide recommendations for science‐based wolf conservation and management at regional and Europe‐wide scales. 相似文献
112.
Exposure of roots to low Cd concentration induced morphogenic responses including the inhibition of root growth and the radial swelling of root tip. High Cd concentrations within a few minutes caused a robust induction of superoxide generation leading to the cell death and root growth arrest. This toxic superoxide generation blocked the development of low Cd concentration-activated morphogenic responses. While the morphogenic responses of roots to low Cd concentration are induced very rapidly and probably due to the interaction of Cd with the apoplast of root tissue, high Cd concentration-induced superoxide production required the entry of Cd into the symplast. Auxin signaling is involved in the activation of Cd-induced morphogenic defence responses but not in the Cd-induced toxic superoxide generation. These results suggest that oxidative stress is not a primary cause for the Cd-induced morphogenic responses such as growth reduction and radial cell expansion in barley root tips. 相似文献
113.
Sodium methoxide-promoted methanolysis of 7-deoxy-7-nitro-L-glycero-L-galacto-heptitol peracetate rapidly and nearly quantitatively accumulates 7-deoxy-6-O-methyl-7-nitro-L-glycero-L-galacto-heptitol. The prolonged treatment then provides 76% of D-galactofuranosyl nitromethanes and finally results in the equilibrium of 77% of β-D-galactopyranosyl nitromethane and 7-9% of three other tautomeric D-galactosyl nitromethanes. Thermal treatment of 7-deoxy-7-nitro-L-glycero-L-galacto-heptitol in boiling water peaks at a 58% content of D-galactofuranosyl nitromethanes and ends in a similar equilibrium mixture of four D-galactosyl tautomers. The relevant kinetic parameters of the latter transformation are determined by a curve fitting using the nonlinear least-squares Marquardt-Levenberg algorithm. 相似文献
114.
A role of non-reducing sugars like sucrose and raffinose in the protection of plant cells against damage during freezing has
been proposed for many species, but reports on physiological effects are conflicting. Non-aqueous fractionation of mesophyll
cell compartments in Arabidopsis thaliana was used to show that sucrose and raffinose accumulate in plastids during low temperatures, pointing to a physiological role
in protecting the photosynthetic apparatus. Comparing a previously described raffinose synthase (RS) mutant of A. thaliana with its corresponding wild type, accession Col-0, revealed that a lack of raffinose has no effect on electrolyte leakage
from leaf cells after freeze–thaw cycles, supporting that raffinose is not essential for protecting the plasma membrane. However,
in situ chlorophyll fluorescence showed that maximum quantum yield of PS II photochemistry (F
v/F
m) and other fluorescence parameters of cold acclimated leaves subjected to freeze–thaw cycles were significantly lower in
the raffinose synthase mutant than in the corresponding wild type, indicating that raffinose is involved in stabilizing PS
II of cold acclimated leaf cells against damage during freezing. 相似文献
115.
Vidrna L Černý I Pouzar V Borovská J Vyklický V Vyklický L Chodounská H 《Steroids》2011,76(10-11):1043-1050
Analogs of pregnanolone (3α-hydroxy-5β-pregnan-20-one), modified in position 17 were prepared. Compounds with 20-keto pregnane side chain replaced completely by azide (17α- and 17β-azido-5β-androstan-3α-ol), compounds with its part replaced (20-azido-21-nor-5β-pregnan-3α-ol), and compounds with keto group only replaced ((20R)- and (20S)-20-azido-5β-pregnan-3α-ol) were synthesized using tosylate displacements with sodium azide or Mitsunobu reaction with azoimide. All five azido steroids were converted into corresponding sulfates. Subsequent tests for inhibition of glutamate induced response on NMDA receptors revealed that modification of pregnanolone sulfate side chain with azide did not disturb the activity and some of sulfates tested were more active than parent compound. 相似文献
116.
Many techniques have been applied to understand viral cell-to-cell movement in host plants, but little progress has been made in understanding viral vascular transport mechanisms. We propose the use of chlorophyll fluorescence imaging techniques, not only to diagnose the viral infection, but also to follow the movement of the virus through the vascular system and its subsequent spread into the leaves. In Nicotiana benthamiana plants, imaging of chlorophyll fluorescence parameters such as ФPSII and NPQ proved useful to follow infections with Pepper mild mottle virus. The results demonstrate a correlation between changes in the chlorophyll fluorescence parameters and the viral distribution analyzed by tissue printing. 相似文献
117.
118.
Ilona Hromadnikova Katerina Kotlabova Lucie Hympanova Jindrich Doucha Ladislav Krofta 《PloS one》2014,9(12)
Objective
The objective of the study was to evaluate risk assessment for gestational hypertension based on the profile of circulating placental specific C19MC microRNAs in early pregnancy.Study design
The prospective longitudinal cohort study of women enrolled at first trimester screening at 10 to 13 weeks was carried out (n = 267). Relative quantification of placental specific C19MC microRNAs (miR-516-5p, miR-517*, miR-518b, miR-520a*, miR-520h, miR-525 and miR-526a) was determined in 28 normal pregnancies and 18 pregnancies which developed gestational hypertension using real-time PCR and a comparative Ct method relative to synthetic C. elegans microRNA (cel-miR-39).Results
Increased extracellular C19MC microRNA plasmatic levels (miR-516-5p, p<0.001; miR-517*, p = 0.007; miR-520h, p<0.001; miR-518b, p = 0.002) were detected in patients destined to develop gestational hypertension. MiR-520h had the best predictive performance with a PPV of 84.6% at a 7.1% false positive rate. The combination of miR-520h and miR-518b was able to predict 82.6% of women at the same false positive rate. The overall predictive capacity of single miR-518b (73.3% at 14.3% FPR), miR-516-5p (70.6% at 17.9% FPR) and miR-517* (57.9% at 28.6% FPR) biomarkers was lower.Conclusion
The study brought interesting finding that the up-regulation of miR-516-5p, miR-517*, miR-520h and miR-518b is associated with a risk of later development of gestational hypertension. First trimester screening of extracellular miR-520h alone or in combination with miR-518b identified a significant proportion of women with subsequent gestational hypertension. 相似文献119.
Development of a 16S rRNA gene-based prototype microarray for the detection of selected actinomycetes genera 总被引:1,自引:0,他引:1
Kyselková M Kopecký J Felföldi T Cermák L Omelka M Grundmann GL Moënne-Loccoz Y Ságová-Marecková M 《Antonie van Leeuwenhoek》2008,94(3):439-453
Actinomycetes are known for their secondary metabolites, which have been successfully used as drugs in human and veterinary medicines. However, information on the distribution of this group of Gram-positive bacteria in diverse ecosystems and a comprehension of their activities in ecosystem processes are still scarce. We have developed a 16S rRNA-based taxonomic microarray that targets key actinomycetes at the genus level. In total, 113 actinomycete 16S rRNA probes, corresponding to 55 of the 202 described genera, were designed. The microarray accuracy was evaluated by comparing signal intensities with probe/target-weighted mismatch values and the Gibbs energy of the probe/target duplex formation by hybridizing 17 non-actinomycete and 29 actinomycete strains/clones with the probe set. The validation proved that the probe set was specific, with only 1.3% of false results. The incomplete coverage of actinomycetes by a genus-specific probe was caused by the limited number of 16S rRNA gene sequences in databases or insufficient 16S rRNA gene polymorphism. The microarray enabled discrimination between actinomycete communities from three forest soil samples collected at one site. Cloning and sequencing of 16S rRNA genes from one of the soil samples confirmed the microarray results. We propose that this newly constructed microarray will be a valuable tool for genus-level comparisons of actinomycete communities in various ecological conditions. 相似文献
120.
Ziegelhöffer Attila Ravingerová Tanya Styk Ján Šeboková Jana Waczulíkova Iveta Breier Albert Džurba Andrej Volkovová Katarína Čársky Jozef Turecký Ladislav 《Molecular and cellular biochemistry》1997,176(1-2):191-198
In diabetes the hearts exhibit impaired membrane functions, but also increased tolerance to Ca2+ (iCaT) However, neither the true meaning nor the molecular mechanisms of these changes are fully understood. The present study is devoted to elucidation of molecular alterations, particularly those induced by non-enzymatic glycation of proteins, that may be responsible for iCaT of the rat hearts in the stage of fully developed, but still compensated diabetic cardiomyopathy (DH). Insulin-dependent diabetes (DIA) was induced by a single i.v. dose of streptozotocin (45 mg.kg-1). Beginning with the subsequent day, animals obtained 6 U insulin daily. Glucose, triglycerides, cholesterol and glycohemoglobin were investigated in blood. ATPase activities, the kinetics of activation of (Na,K)-ATPase by Na+ and K+, further the fluorescence anisotropy of diphenyl-hexatriene as well as the order parameters of membranes in isolated heart sarcolemma (SL) were also investigated. In addition, the degree of glycation and glycation-related potency for radical generation in SL proteins were determined by investigating their fructosamine content. In order to study calcium tolerance of DH in a 'transparent' model, hearts were subjected to calcium paradox (Ca-Pa, 3 min of Ca2+ depletion; 10 min of Ca2+ repletion). In this model of Ca2+-overload, Ca2+ ions enter the cardiac cells in a way that is not mediated by receptors. Results revealed that more than 83% of the isolated perfused DH recovered, while the non-DIA control hearts all failed after Ca-Pa. DH exhibited well preserved SL ATPase activities and kinetics of (Na,K)-ATPase activation by Na+, even after the Ca-Pa. This was considered as a reason for their iCaT. Pretreatment and administration of resorcylidene aminoguanidine (RAG 4 or 8 mg.kg-1) during the disease prevented partially the pathobiochemical effects of DIA-induced glycation of SL proteins. DIAinduced perturbations in anisotropy and order parameters of SL were completely prevented by administration of RAG (4 mg.kg-1). Although, the latter treatment exerted little influence on the (Na,K)-ATPase activity, it decreased the calcium tolerance of the DH. Results are supporting our hypothesis that the glycation-induced enhancement in free radical formation and protein crosslinking in SL may participate in adaptive mechanisms that may be also considered as 'positive' and are responsible for iCaT of the DH. 相似文献