A large-scale survey of genetic variation and genome evolution within the invasive Reynoutria complex : [streszczenie]

The taxa from the genus Reynoutria: R. japonica, R. sachalinensis, originating from Asia, and their hybrid R. ×bohemica are some of the most troublesome alien invasive species in Europe and North America, particularly dangerous to riparian ecosystems. Simultaneously, these taxa constitute a unique model system for the creation of hybrids and the initiation of evolutionary processes in an invaded range. The aim of the study was: (i) to examine the level of genetic diversity using Amplified Fragment Length Polymorphism (AFLP) markers in selected populations of three Reynoutria taxa from Poland, Hungary, Ukraine and Slovakia in comparison with Japan, (ii) to identify marked chromosomes in all taxa using fluorescence in situ hybridization (FISH) with rDNA sequences, and (iii) to establish genome size and ploidy level in the knotweed species using flow cytometry (FCM) (Fragment tekstu)

Arytmia z piekła rodem. Idiopatyczny pęczkowy częstoskurcz komorowy u młodej kobiety

Idiopathic left fascicular ventricular tachycardia (ILFVT) is characterized by right bundle branch block (RBBB) morphology and left axis deviation. We report a case of ILFVT in a young 27-year-old female patient presenting with a narrow complex tachycardia resistant to vagal maneuvers, adenosine, lidocaine, and electrical cardioversion.Idiopathic left fascicular ventricular tachycardia (ILFVT) is characterized by right bundle branch block (RBBB) morphology and left axis deviation. We report a case of ILFVT in a young 27-year-old female patient presenting with a narrow complex tachycardia resistant to vagal maneuvers, adenosine, lidocaine, and electrical cardioversion

Cytogenetic and molecular genotyping in the allotetraploid Festuca pratensis × Lolium perenne hybrids

Background: Species of the Festuca and Lolium genera, as well as intergeneric Festuca × Lolium (Festulolium) hybrids, are valuable fodder and turf grasses for agricultural and amenity purposes worldwide. Festulolium hybrids can merge in their genomes agronomically important characteristics. However, in polyploid plants, especially in allopolyploids, the hybridization of divergent genomes could contribute to various abnormalities, such as variability in chromosome number, structural rearrangements, and/or disorders in inheritance patterns. Here we studied these issues in allotetraploid Festuca pratensis × Lolium perenne hybrids. Results: Cytogenetic procedures, including fluorescent in situ hybridization, genomic in situ hybridization, and molecular markers – inter-simple sequence repeats (ISSR) were exploited. This cytogenetic approach indicated the dynamics in the number and distribution of ribosomal RNA genes and structural rearrangements for both parental genomes (Festuca and Lolium) in hybrid karyotypes. The separate analysis of F. pratensis and L. perenne chromosomes in hybrid plants (F2-F3 generations of F. pratensis × L. perenne) revealed the asymmetrical level of rearrangements. Recognized structural changes were mainly located in the distal part of chromosome arms, and in chromosomes bearing ribosomal DNA, they were more frequently mapped in arms without this sequence. Based on the ISSR markers distribution, we found that the tetrasomic type of inheritance was characteristic for the majority of ISSR loci, but the disomic type was also observed. Nonetheless, no preference in the transmission of either Festuca or Lolium alleles to the following generations of allotetraploid F. pratensis × L. perenne hybrid was observed. Conclusion: Our study reports cytogenetic and molecular genotyping of the F. pratensis × L. perenne hybrid and its following F2-F3 progenies. The analysis of 137 allotetraploid F. pratensis × L. perenne hybrids revealed the higher level of recombination in chromosomes derived from F. pratensis genome. The results of ISSR markers indicated a mixed model of inheritance, which may be characteristic for these hybrids

A Survey of Genetic Variation and Genome Evolution within the Invasive Fallopia Complex

The knotweed taxa Fallopia japonica, F. sachalinensis and their interspecific hybrid F. x bohemica are some of the most aggressive invaders in Europe and North America and they are serious threats to native biodiversity. At the same time, they constitute a unique model system for the creation of hybrids and studies of the initiation of evolutionary processes. In the presented study, we focused on (i) examining genetic diversity in selected populations of three Fallopia taxa in the invaded (Poland) and native ranges (Japan), (ii) establishing genome size and ploidy levels and (iii) identifying ribosomal DNA (rDNA)-bearing chromosomes in all of the taxa from the invaded range. We found that the genetic diversity within particular taxa was generally low regardless of their geographical origin. A higher level of clonality was observed for the Polish populations compared to the Japanese populations. Our study suggests that the co-occurrence of F. sachalinensis together with the other two taxa in the same stand may be the source of the higher genetic variation within the F. x bohemica hybrid. Some shift towards the contribution of F. japonica alleles was also observed for selected F. x bohemica individuals, which indicates the possibility of producing more advanced generations of F. x bohemica hybrids. All of the F. sachalinensis individuals were hexaploid (2n = 6x = 66; 2C = 6.01 pg), while those of F. japonica were mostly octoploid (2n = 8x = 88; 2C = 8.87 pg) and all of the F. x bohemica plants except one were hexaploid (2n = 6x = 66; 2C = 6.46 pg). Within the chromosome complement of F. japonica, F. sachalinensis and F. x bohemica, the physical mapping of the rDNA loci provided markers for 16, 13 and 10 chromosomes, respectively. In F. x bohemica, a loss of some of rDNA loci was observed, which indicates the occurrence of genome changes in the hybrid

Electrocardiograms in school-aged healthy Polish children — an observational study

Background: Electrocardiographic (ECG) examination has long been used to assess cardiovascular function in clinical practice. Age-related ECG changes are observed as the cardiovascular system matures from the neonatal period to adolescence.  Aim: This study aimed to evaluate the effects of sex and age on ECG parameters in healthy schoolchildren. Methods: The study included 336 healthy participants aged 5–12 years from Masovian voivodeship. Children were divided into age groups of 5–8 and 9–12 years. Values for heart rate (HR), time intervals and amplitudes of P and QRS waves, and QRS axis for pediatric ECGs were estimated. Results: Significant differences between boys and girls aged 5–8 years old were discovered for such parameters as PR interval, R-wave, and S-wave, R/S ratio. Age-related decline in HR, Q-wave in V5, and V6, R-wave in V1–V4, and increase in QRS duration were noted. Girls presented higher HR and shorter QRS than boys. HR, QRS axis, P wave amplitude in the II lead, and amplitude of R and S in the precordial leads were different in our population than previously reported. Conclusions: Pediatric ECG tracings were estimated for the first time for school-aged Polish healthy children. Sex-related differences in selected ECG parameters in the younger age group were noticed. Several parameters differed from those previously reported in other ethnic populations. These findings are clinically significant and suggest that diagnostic criteria for pediatric ECG should be revised to establish if they are justifiable for the entire population

Orthology guided transcriptome assembly of Italian ryegrass and meadow fescue for single-nucleotide polymorphism discovery

Single-nucleotide polymorphisms (SNPs) represent natural DNA sequence variation. They can be used for various applications including the construction of high-density genetic maps, analysis of genetic variability, genome-wide association studies, and mapbased cloning. Here we report on transcriptome sequencing in the two forage grasses, meadow fescue (Festuca pratensis Huds.) and Italian ryegrass (Lolium multiflorum Lam.), and identification of various classes of SNPs. Using the Orthology Guided Assembly (OGA) strategy, we assembled and annotated a total of 18,952 and 19,036 transcripts for Italian ryegrass and meadow fescue, respectively. In addition, we used transcriptome sequence data of perennial ryegrass (L. perenne L.) from a previous study to identify 16,613 transcripts shared across all three species. Large numbers of intraspecific SNPs were identified in all three species: 248,000 in meadow fescue, 715,000 in Italian ryegrass, and 529,000 in perennial ryegrass. Moreover, we identified almost 25,000 interspecific SNPs located in 5343 genes that can distinguish meadow fescue from Italian ryegrass and 15,000 SNPs located in 3976 genes that discriminate meadow fescue from both Lolium species. All identified SNPs were positioned in silico on the seven linkage groups (LGs) of L. perenne using the GenomeZipper approach. With the identification and positioning of interspecific SNPs, our study provides a valuable resource for the grass research and breeding community and will enable detailed characterization of genomic composition and gene expression analysis in prospective Festuca Lolium hybrids