Reconstructing the invasion history of Heracleum persicum (Apiaceae) into Europe

Sparse, incomplete and inappropriate historical records of invasive species often hamper invasive species management interventions. Population genetic analyses of invaders might provide a suitable context for the identification of their source populations and possible introduction routes. Here, we describe the population genetics of Heracleum persicum Desf. ex Fisch and trace its route of introduction into Europe. Microsatellite markers revealed a significantly higher genetic diversity of H. persicum in its native range, and the loss of diversity in the introduced range may be attributed to a recent genetic bottleneck. Bayesian cluster analysis on regional levels identified three and two genetic clusters in the native and the introduced ranges, respectively. A global structure analysis revealed two worldwide distinct genetic groups: one primarily in Iran and Denmark, the other primarily in Norway. There were also varying degrees of admixture in England, Sweden, Finland and Latvia. Approximate Bayesian computation indicated two independent introductions of H. persicum from Iran to Europe: the first one in Denmark and the second one in England. Finland was subsequently colonized by English populations. In contrast to the contemporary hypothesis of English origin of Norwegian populations, we found Finland to be a more likely source for Norwegian populations, a scenario supported by higher estimated histor‐ical migration from Finland to Norway. Genetic diversity per se is not a primary determinant of invasiveness in H. persicum. Our results indicate that, due to either pre‐adaptations or rapid local adaptations, introduced populations may have acqu‐ired invasiveness after subsequent introductions, once a suitable environment was encountered.     

Changes in Malate Content and in Enzymes Involved in Dark CO2 Fixation during Growth of Acer pseudoplatanus Cells in Suspension Culture

It has been reported in some cases that an increase in pCO₂ stimulates growth in diluted cell suspension cultures. Experiments have been designed to study the pattern of dark CO₂ fixation in sycamore cells grown in liquid suspension and to correlate this pattern with the culture growth phases. Comparisons were made between enzymatic activities, CO₂ incorporation, malic acid content during lag, logarithmic and stationary phases of growth. Malic enzyme (NADP-dependent) was at its maximum activity during early logarithmic growth phase, when biosynthetic capacities were at the highest. Phosphoenolpyruvate-carboxylase activity was strongly correlated with the ability of cells to fix CO₂. Malic acid content decreased soon after transfer of the cells to a new medium and increased at the onset of stationary phase. Under optimal conditions, the CO₂ incorporation pattern did not change during growth, with an almost identical incorporation in the basic (amino acids) and acidic (organic acids) fractions. These observations have been discussed in relation to a possible effect of increased pCO₂ in the cell environment.     

Giant invasive Heracleum persicum: Friend or foe of plant diversity?

The impact of invasion on diversity varies widely and remains elusive. Despite the considerable attempts to understand mechanisms of biological invasion, it is largely unknown whether some communities’ characteristics promote biological invasion, or whether some inherent characteristics of invaders enable them to invade other communities. Our aims were to assess the impact of one of the massive plant invaders of Scandinavia on vascular plant species diversity, disentangle attributes of invasible and noninvasible communities, and evaluate the relationship between invasibility and genetic diversity of a dominant invader. We studied 56 pairs of Heracleum persicum Desf. ex Fisch.‐invaded and noninvaded plots from 12 locations in northern Norway. There was lower native cover, evenness, taxonomic diversity, native biomass, and species richness in the invaded plots than in the noninvaded plots. The invaded plots had nearly two native species fewer than the noninvaded plots on average. Within the invaded plots, cover of H. persicum had a strong negative effect on the native cover, evenness, and native biomass, and a positive association with the height of the native plants. Plant communities containing only native species appeared more invasible than those that included exotic species, particularly H. persicum. Genetic diversity of H. persicum was positively correlated with invasibility but not with community diversity. The invasion of a plant community by H. persicum exerts consistent negative pressure on vascular plant diversity. The lack of positive correlation between impacts and genetic diversity of H. persicum indicates that even a small founder population may cause high impact. We highlight community stability or saturation as an important determinant of invasibility. While the invasion by H. persicum may decrease susceptibility of a plant community to further invasion, it severely reduces the abundance of native species and makes them more vulnerable to competitive exclusion.     

The simplest method for in vitro β-cell production from human adult stem cells

Diabetes mellitus is a challenging autoimmune disease. Biomedical researchers are currently exploring efficient and effective ways to solve this challenge. The potential of stem cell therapies for treating diabetes represents one of the major focuses of current research on diabetes treatment. Here, we have attempted to differentiate adult stem cells from umbilical cord blood-derived mesenchymal cells (UCB-MSC), Wharton's jelly-derived mesenchymal stem cells (WJ-MSC) and amniotic epithelial stem cells (AE-SC) into insulin-producing cells. The serum-free protocol developed in this study resulted in the differentiation of cells into definitive endoderm, pancreatic foregut, pancreatic endoderm and, finally, pancreatic endocrine cells, which expressed the marker genes SOX17, PDX1, NGN3, NKX6.1, INS, GCG, and PPY, respectively. Detection of the expression of the gap junction-related gene connexin-36 (CX36) using RT-PCR provided conclusive evidence for insulin-producing cell differentiation. In addition to this RT-PCR result, insulin and C-peptide protein were detected by immunohistochemistry and ELISA. Glucose stimulation test results showed that significantly greater amounts of C-peptide and insulin were released from differentiated cells than from undifferentiated cells. In conclusion, the methods investigated in this study can be considered an effective and efficient means of obtaining insulin-producing cells from adult stem cells within a week.     

Disentangling the genetic origin of Heracleum persicum (Apiaceae) in Europe: multiple introductions from multiple source populations

Biological Invasions - Unraveling the origin and colonization history of invasive plants is a long-standing challenge in evolutionary and conservation biology. The knowledge of the origin of the...     

Production of fermented needle extracts from red pine and their functional characterization

Pine needle (Pinus densiflora Sieb. et Zucc.) extract is being used for millennia in treatment of multiple ailments in Asia Pacific region. The extract is a composite mixture of a number of organic compounds. Terpenoid is one of such complex compounds that exhibit useful effects. To remove harmful substances with improving functionality of the extract, people adopt traditional spontaneous fermentation followed by aging. To assess the fermentation induced effectiveness we analyzed composition of the volatile terpenoid in fresh to the 7 years old self-fermented extracts along with their anti-bacterial and anti-oxidant properties. Simultaneously, we also analyzed the effect of remarkably changed 1,8-cineole and camphor. SFPEs (self-fermented pine needle extracts), 1,8-cineole, and camphor inhibited growth of bacterial strains like Salmonella typhimurium, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis. Comparative studies between pine needle extracts, 1,8-cineole and camphor showed that the self-fermented pine needle extracts retard the bacterial growth effectively and have relatively higher antioxidant activities. PE (pine needle extract) and SFPEs showed nearly 95% DPPH radical scavenging activities, 1,8-cineole 84% while camphor showed no scavenging activities. The results showed that self-fermentation and aging improves the effects of the extract therefore it could be a good source for nutraceutical product.     

A case of congenital warfarin syndrome due to maternal drug administration during the pregnancy

Warfarin, which is used for anticoagulant therapy, rarely produces congenital warfarin syndrome characterized with hypoplastic nose, stippled epiphyses, and skeletal abnormalities when ingested during pregnancy. Here, we present a male infant, whose mother was treated with warfarin because of a prosthetic heart valve replacement after rheumatic heart disease, with signs of warfarin embryopathy. The mother's first pregnancy at 12 weeks gestation resulted in abortus due to warfarin toxicity. Subsequently, she delivered two healthy girls after her treatment had changed to low molecular heparin during pregnancy periods. We want to emphasize that risk-benefit ratio should be well weighed by both obstetricians and cardiologists when considering warfarin therapy for a woman at childbearing age.     

Influence of the<Emphasis Type=Italic>SMT2</Emphasis> knock-out on hypocotyl elongation in<Emphasis Type=Italic>Arabidopsis thaliana</Emphasis>

Inhibitors are very important in the study of hormone function. Brasinazole (Brz) is a specific inhibitor of brassinosteroids (BRs) biosynthesis. To expand our knowledge of the molecular mechanisms of plant steroid signaling, we performed genetic screening using medium containing Brz under dark conditions. Mutants insensitive to Brz developlonger hypocotyls than their wild type counterparts. We isolatedabz453 as a Brz insensitive mutant. TAIL-PCR and the segregation ratio of T2 plants indicated a single T-DNA insertion at the 24-Sterol C-methyltransferase (SMT2) gene in theabz453 mutant. Recapitulation for putative FCP serine phosphatase (FSP), the gene neighboringSMT2, indicated no significant phenotypes, but theSMT2 anti-sense (SMT2-AS) line developed longer hypocotyls than the wild type in medium containing Brz. Additionally, theSMT2-AS line displayed similar phenotypes to theabz453 line in soil including enhanced growth and smaller silique. Theabz453 andSMT2-AS mutants showed phenotypes similar to those of wild type in medium containing benzylaminopurine, pacrobutrazol and ACC (precursor for ethylene) under dark conditions. However, when brassinolide (BL) dose response was observed, theabz453 andSMT2-AS lines showed higher sensitivity than wild type. Theabz453/det2 andabz453/bri1-119 double mutants showed enhanced growth compared to thedet2 andbri1-119 line under both dark and light conditions. Specially, in dark conditions double mutants displayed nearly 2- and 1.5-fold longer hypocotyls thandet2 andbri1-119 plants. Brz insensitivity to theSMT2 knock-out mutant and phenotypes of double mutants indicate that not only do BRI1 and DET2 influence the BRs response, as evidenced by hypocotyl elongation, but another sterol derived signals may also be affected in mutants, suggesting that another pathway is involved in hypocotyl elongation due to SMT2.