Multi-Year Monitoring of the Tick–Pathogen System in Natural Foci of Tick-Borne Encephalitis in the Suburbs of Irkutsk

Entomological Review - The state of the natural foci of tick-borne encephalitis (TBE) was monitored during 15 seasons (2005–2019) in several key plots within a popular recreational and...     

Glutathione reductase gene expression depends on chloroplast signals in <Emphasis Type="Italic">Arabidopsis thaliana</Emphasis>

Glutathione reductase (EC 1.6.4.2) is one of the main antioxidant enzymes of the plant cell. In Arabidopsis thaliana, glutathione reductase is encoded by two genes: the gr1 gene encodes the cytosolic-peroxisomal form, and the gr2 gene encodes the chloroplast-mitochondrial form. Little is known about the regulation of expression of plant glutathione reductase genes. In the present work, we have demonstrated that gr2 (but not gr1) gene expression in Arabidopsis leaves changes depending on changes in redox state of the photosynthetic electron transport chain. Expression of both the gr1 and gr2 genes was induced by reactive oxygen species. In heterotrophic suspension cell culture of Arabidopsis, expression of both studied genes did not depend on H₂O₂ level or on changes in the redox state of the mitochondrial electron transport chain. Our data indicate that chloroplasts are involved in the regulation of the glutathione reductase gene expression in Arabidopsis.     

Extension of the Messapia x dicoccoides linkage map of Triticum turgidum (L.) Thell

A set of recombinant inbred lines (RIL) derived from a cross between the cultivar Messapia of durum wheat (Triticum turgidum var. durum) and the accession MG4343 of T. turgidum var. dicoccoides was analysed to increase the number of assigned markers and the resolution of the previously constructed genetic linkage map. An updated map of the durum wheat genome consisting of 458 loci was constructed. These loci include 261 Restriction Fragment Length Polymorphisms (RFLPs), 91 microsatellites (Simple Sequence Repeats, SSRs), 87 Amplified Fragment Length Polymorphisms (AFLPs), two ribosomal genes, and nine biochemical (seven seed storage proteins and two isozymes) and eight morphological markers. The loci were mapped on all 14 chromosomes of the A and B genomes, and covered a total distance of 3038.4 cM with an average distance of 6.7 cM between adjacent markers. The molecular markers were evenly distributed between the A and the B genomes (240 and 218 markers, respectively). An additional forty loci (8.8%) could not be assigned to a specific linkage group. A fraction (16.4%) of the markers significantly deviated from the expected Mendelian ratios; clusters of loci showing distorted segregation were found on the 1B, 2A, 2B, 3A, 4A, 7A and 7B chromosomes. The genetic lengths of the chromosomes range from 148.8 cM (chromosome 6B) to 318.0 cM (chromosome 2B) and approximately concur with their physical lengths. Chromosome 2B has the largest number of markers (47), while the chromosomes with the fewest markers are 3A and 6B (23). There are two gaps larger than 40 cM on chromosomes 2A and 3B. The durum wheat map was compared with the published maps of bread and durum wheats; the order of most common RFLP and SSR markers on the 14 chromosomes of the A and B genomes were nearly identical. A core-map can be extracted from the high-density Messapia x dicoccoides map and a subset of uniformly distributed markers can be used to detect and map quantitative trait loci.     

Morphofunctional study of the bill and hyoid apparatus of Momotus momota (Aves, Coraciiformes, Momotidae): implications for omnivorous feeding adaptation in motmots

The present study contrasts available biological data and results of morphofunctional analyses of the bill and hyoid apparatus in motmots. It shows that these omnivorous birds, which take relatively large food items, possess osteomuscular peculiarities that enable them to process these items as a whole in order to soften or cut them, and make them suited for easy ingestion. For that, they use the crenate edges of their rhamphotheca. Their jaws work as a highly mobile saw-like system. Their mutual movements, enhanced by the fact that particular dispositions of the hyoid apparatus rise the tongue and the supported items high up into buccal cavity, facilitate an effective clamping of items that can be moved along the jaws and be quite appropriately processed.     

Cytologically integrated physical restriction fragment length polymorphism maps for the barley genome based on translocation breakpoints

We have developed a new technique for the physical mapping of barley chromosomes using microdissected translocation chromosomes for PCR with sequence-tagged site primers derived from >300 genetically mapped RFLP probes. The positions of 240 translocation breakpoints were integrated as physical landmarks into linkage maps of the seven barley chromosomes. This strategy proved to be highly efficient in relating physical to genetic distances. A very heterogeneous distribution of recombination rates was found along individual chromosomes. Recombination is mainly confined to a few relatively small areas spaced by large segments in which recombination is severely suppressed. The regions of highest recombination frequency (相似文献   

Procalcitonin Identifies Cell Injury,Not Bacterial Infection,in Acute Liver Failure

Background

Because acute liver failure (ALF) patients share many clinical features with severe sepsis and septic shock, identifying bacterial infection clinically in ALF patients is challenging. Procalcitonin (PCT) has proven to be a useful marker in detecting bacterial infection. We sought to determine whether PCT discriminated between presence and absence of infection in patients with ALF.

Method

Retrospective analysis of data and samples of 115 ALF patients from the United States Acute Liver Failure Study Group randomly selected from 1863 patients were classified for disease severity and ALF etiology. Twenty uninfected chronic liver disease (CLD) subjects served as controls.

Results

Procalcitonin concentrations in most samples were elevated, with median values for all ALF groups near or above a 2.0 ng/mL cut-off that generally indicates severe sepsis. While PCT concentrations increased somewhat with apparent liver injury severity, there were no differences in PCT levels between the pre-defined severity groups–non-SIRS and SIRS groups with no documented infections and Severe Sepsis and Septic Shock groups with documented infections, (p = 0.169). PCT values from CLD patients differed from all ALF groups (median CLD PCT value 0.104 ng/mL, (p ≤0.001)). Subjects with acetaminophen (APAP) toxicity, many without evidence of infection, demonstrated median PCT >2.0 ng/mL, regardless of SIRS features, while some culture positive subjects had PCT values <2.0 ng/mL.

Summary/Conclusions

While PCT appears to be a robust assay for detecting bacterial infection in the general population, there was poor discrimination between ALF patients with or without bacterial infection presumably because of the massive inflammation observed. Severe hepatocyte necrosis with inflammation results in elevated PCT levels, rendering this biomarker unreliable in the ALF setting.     

Molecular marker assisted broadening of the Central European heterotic groups in rye with Eastern European germplasm

Broadening the genetic base of heterotic pools is a key to ensure continued genetic gains in hybrid breeding and extend hybrid cultivation to new areas. In the present study, two Central European heterotic pools (Carsten and Petkus) and five Eastern European open-pollinated varieties (OPVs, Pop-1 to Pop-5) were studied with the objectives to (1) investigate the genetic diversity in OPVs and the heterotic pools using molecular and field data, (2) evaluate the molecular diversity among OPVs, (3) examine the combining ability for grain yield of the OPVs when crossed with testers in field trials, and (4) develop a strategy for targeted introgression of OPV germplasm into the heterotic pools. In total, 610 S₀ plants, 347 from OPVs and 263 from heterotic pools, were developed. Clones of the S₀ plants of OPVs were crossed with two testers belonging to each heterotic pool, while clones of heterotic pools were crossed with only the opposite tester. Testcrosses were evaluated for grain yield in multi-location trials. In addition, 589 S₀ plants were fingerprinted with 30 SSR markers. The data revealed that the Carsten pool has a narrow genetic base and should be the primary target for broadening the established heterotic pattern. Mean and genetic variance suggested that Pop-2 and Pop-4 are good candidates for introgression in Petkus pool and Pop-5 in Carsten pool. Nevertheless, introgression of Pop-5 in Carsten could reduce the genetic diversity between heterotic pools. Therefore, we suggest that either selected plants of Pop-5 should be introgressed or more Eastern European germplasm should be fingerprinted and field evaluated to identify promising germplasm for broadening the established heterotic pattern.     

Potential and limits to unravel the genetic architecture and predict the variation of Fusarium head blight resistance in European winter wheat (Triticum aestivum L.)

Genome-wide mapping approaches in diverse populations are powerful tools to unravel the genetic architecture of complex traits. The main goals of our study were to investigate the potential and limits to unravel the genetic architecture and to identify the factors determining the accuracy of prediction of the genotypic variation of Fusarium head blight (FHB) resistance in wheat (Triticum aestivum L.) based on data collected with a diverse panel of 372 European varieties. The wheat lines were phenotyped in multi-location field trials for FHB resistance and genotyped with 782 simple sequence repeat (SSR) markers, and 9k and 90k single-nucleotide polymorphism (SNP) arrays. We applied genome-wide association mapping in combination with fivefold cross-validations and observed surprisingly high accuracies of prediction for marker-assisted selection based on the detected quantitative trait loci (QTLs). Using a random sample of markers not selected for marker–trait associations revealed only a slight decrease in prediction accuracy compared with marker-based selection exploiting the QTL information. The same picture was confirmed in a simulation study, suggesting that relatedness is a main driver of the accuracy of prediction in marker-assisted selection of FHB resistance. When the accuracy of prediction of three genomic selection models was contrasted for the three marker data sets, no significant differences in accuracies among marker platforms and genomic selection models were observed. Marker density impacted the accuracy of prediction only marginally. Consequently, genomic selection of FHB resistance can be implemented most cost-efficiently based on low- to medium-density SNP arrays.     

Bill and hyoid apparatus of pigeons (Columbidae) and sandgrouse (Pteroclididae): a common adaptation to vegetarian feeding?

For the present study, 15 species of pigeons representing the 5 sub-families usually recognized, and 3 species of sandgrouse were examined. The skeleton and musculature of the bill and hyoid apparatus are described. Morpho-functional analyses show that from a key adaptation to the removal and deglutition (without processing) of attached plant items, pigeons would have followed two pathways, one based on the joint muscular control of the movement of the jaws (Columbinae, Treroninae, Gourinae), the other on the separate muscular control (Didunculinae, Otidiphabinae). Sandgrouse would have diverged from this latter, developing the ability to very selectively remove attached plant items as well as to peck particularly small seeds on the ground. Unexpected differences appeared between sandgrouse species which raise eco-ethological problems.