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The aim of this work was to gather information about the origin and genetic characterization of the Central European Hucul horse based on 71 horses using 17 microsatellites and the D‐loop region of mtDNA. Their genetic relationship to the Polish Konik (N = 7), German (N = 4) and Hungarian wild Przewalski horses (N = 4) and 200 horse sequences from GenBank was also analysed. Both microsatellite and mtDNA analysis showed a high genetic variation in the Hucul. A total of 130 alleles were detected, the mean number of observed alleles per microsatellite was 7.647, and the number of effective alleles was 4.401. The average observed and expected heterozygosity were 0.706 and 0.747, respectively. The high heterozygosity values and Wright's fixation index (FIS) (?0.128) indicated a low level of inbreeding, low or no selection pressure, and large number of alleles. mtDNA analysis revealed 18 haplotypes for the Hucul population with a total of 23 variable sites. Haplotype and nucleotide diversities were 0.935 ± 0.011 and 0.022 ± 0.012, respectively. Neutrality tests (Tajima's D and Fu's Fs) were non‐significant, and mismatch distribution was ragged, indicating that the Hucul population is in genetic equilibrium. The most frequent mtDNA D‐loop region belonged to haplogroup A (48%), which was also present in Przewalski Wild horse samples, while Polish Konik samples belonged to three haplotypes and C, F, and G haplogroups. Large and significant pairwise ΦST values along with a small number of common haplotypes indicated a low level of gene flow and lack of genetic structure among the three studied breeds (Hucul, Konik, and Przewalski Wild horse). The present work contributes to our knowledge of the genetic diversity of the Hucul horse and helps to define its genetic conservation. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 54–65.  相似文献   
3.
In this paper we describe synthesis, structures and some physicochemical properties of 20 isothiazolopyridines 813 substituted differently into an isothiazole ring as well as their in vitro antibacterial assays against Mycobacterium tuberculosis H37Rv, Mycobacterium fortuitum PCM 672 and Propionibacterium acnes PCM 2400. Compound 13a was found to be the most active derivative against M. tuberculosis H37Rv, demonstrating 100% growth inhibition of microorganisms in the primary screen (minimum inhibitory concentration [MIC] 6.25 μg/mL). Nineteen of the prepared compounds were evaluated against M. fortuitum PCM 672 and P. acnes PCM 2400 and only compounds 9 and 12d exhibited excellent activity against individual strains of microorganisms with MIC90 <1 μg/mL. The inhibitory action of the remaining isothiazolopyridines towards the tested strains of the microorganism was low, absent, or a non-linear correlation prohibited accurate determination of MIC values. Unexpectedly, seven of the remaining isothiazolopyridines tested against M. fortuitum and P. acnes stimulated growth of the microorganisms in the range 10–50% or even more (10b) under experimental conditions.  相似文献   
4.
Enzymes in Bast Fibrous Plant Processing   总被引:7,自引:0,他引:7  
The program COST Action 847 Textile Quality and Biotechnology (2000–2005) has given an excellent chance to review the possibilities of the research, aiming at development of the industrial application of enzymes for bast fibrous plant degumming and primary processing. The recent advancements in enzymatic processing of bast fibrous plants (flax, hemp, jute, ramie and alike plants) and related textiles are given. The performance of enzymes in degumming, modification of bast fibres, roving, yarn, related fabrics as well as enzymatic bonding of lignocellulosic composites is provided.  相似文献   
5.
Although the mechanisms controlling gene flow among populations are particularly important for evolutionary processes, they are still poorly understood, especially in the case of large carnivoran mammals with extensive continuous distributions. We studied the question of factors affecting population genetic structure in the grey wolf, Canis lupus, one of the most mobile terrestrial carnivores. We analysed variability in mitochondrial DNA and 14 microsatellite loci for a sample of 643 individuals from 59 localities representing most of the continuous wolf range in Eastern Europe. We tested an array of geographical, historical and ecological factors to check whether they may explain genetic differentiation among local wolf populations. We showed that wolf populations in Eastern Europe displayed nonrandom spatial genetic structure in the absence of obvious physical barriers to movement. Neither topographic barriers nor past fragmentation could explain spatial genetic structure. However, we found that the genetic differentiation among local populations was correlated with climate, habitat types, and wolf diet composition. This result shows that ecological processes may strongly influence the amount of gene flow among populations. We suggest natal-habitat-biased dispersal as an underlying mechanism linking population ecology with population genetic structure.  相似文献   
6.
Previous studies have identified the inhibitory role that the programmed death 1 (PD-1) pathway plays during chronic infection. Blockade of this pathway results in rescue of viral-specific CD8 T cells, as well as reduction of viral loads in mice chronically infected with lymphocytic choriomeningitis virus (LCMV). We tested the effect of combining PD ligand 1 (PD-L1) blockade with an agonistic regimen that induces 4-1BB costimulation during chronic LCMV infection. There is a boosting effect in the rescue of LCMV-specific CD8 T cell responses after dual treatment with PD-L1 blockade and 4-1BB agonistic Abs when the amount and timing of 4-1BB costimulation are carefully controlled. When PD-L1-blocking Abs are given together with a single low dose of anti-4-1BB agonistic Abs, there is an enhanced and stable expansion of viral-specific CD8 T cells. Conversely, when blocking Abs to PD-L1 are given with a repetitive high dose of anti-4-1BB, there is an initial synergistic expansion of viral-specific CD8 T cells by day 7, followed by dramatic apoptosis by day 14. Viral control paralleled CD8 T cell kinetics after dual treatment. By day 7 posttreatment, viral titers were lower in both of the combined regimens (compared with PD-L1 blockade alone). However, whereas the high dose of anti-4-1BB plus PD-L1 blockade resulted in rebound of viral titers to original levels, the low dose of anti-4-1BB plus PD-L1 blockade resulted in a stable reduction of viral loads. These findings demonstrate the importance of carefully manipulating the balance between activating and inhibitory signals to enhance T cell responses during chronic infection.  相似文献   
7.
Fatty acids were identified in monofloral beebread (BB) and bee pollen (BP) loads collected from Trifolium pratense L. A gas chromatography method was used to identify and quantify fatty acids: Thirty-five fatty acids were identified in BB and 42 in BP. A high amount of the healthy n-3 fatty acids was found. The ratio of polyunsaturated fatty acids n-3 to n-6 reached a value of 8.42 and 3.35 in the latter products. The proteomic analysis also was performed on the manually collected T. pratense pollen, and the most abundant protein groups were subjected to mass spectrometry analysis. Proteins identified in T. pratense pollen are involved in the main cellular functions (cell membrane formation, organelles traffic, and mainly metabolic processes). Because of the composition of fatty acids in BB and BP and a variety of proteins present in pollen, these products are considered to be favorable for human nutrition and health.  相似文献   
8.
Reactions associated with the geochemical process of serpentinization can generate copious quantities of hydrogen and low-molecular-weight organic carbon compounds, which may provide energy and nutrients to sustain subsurface microbial communities independently of the photosynthetically supported surface biosphere. Previous microbial ecology studies have tested this hypothesis in deep sea hydrothermal vents, such as the Lost City hydrothermal field. This study applied similar methods, including molecular fingerprinting and tag sequencing of the 16S rRNA gene, to ultrabasic continental springs emanating from serpentinizing ultramafic rocks. These molecular surveys were linked with geochemical measurements of the fluids in an interdisciplinary approach designed to distinguish potential subsurface organisms from those derived from surface habitats. The betaproteobacterial genus Hydrogenophaga was identified as a likely inhabitant of transition zones where hydrogen-enriched subsurface fluids mix with oxygenated surface water. The Firmicutes genus Erysipelothrix was most strongly correlated with geochemical factors indicative of subsurface fluids and was identified as the most likely inhabitant of a serpentinization-powered subsurface biosphere. Both of these taxa have been identified in multiple hydrogen-enriched subsurface habitats worldwide, and the results of this study contribute to an emerging biogeographic pattern in which Betaproteobacteria occur in near-surface mixing zones and Firmicutes are present in deeper, anoxic subsurface habitats.  相似文献   
9.
Ciliates, being one of the main substrates in granular activated sludge (GAS) formation, are treated as a major factor in granulation process. Cilia beats of Opercularia asymmetrica provide a continuous nutrient flux, enhancing the colonization of bacteria on Peritrichia stalks. Given that the ciliates tend to live in colonies, the main focus of the present work was an analysis and comparison of the flow effects induced by a single ciliate and by a colony. Investigations of the flow generated by Opercularia asymmetrica were carried out using micro-particle image velocimetry with biocompatible seeding. The results obtained showed different flow structures for a single ciliate and a colony. Moreover, the synergetic work of Opercularia asymmetrica living in a colony is considered as effective fluid transport. Additionally, analysis of the shear and normal strain rates provided information on mixing phenomena within the fluid on the micro-scale. The influence of seeding substance concentration on the flow pattern was also studied.  相似文献   
10.
The present studies with application of classical strain crosses and RAPD-PCR analyses showed the existence of different genetic species (syngens) within Paramecium jenningsi. So far the existence of only one syngen has been accepted. It was found that strains from Saudi Arabia, India, and China compose one genetic species (syngen 1) and six strains from Japan compose second genetic species (syngen 2).  相似文献   
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