Patient-specific simulation of transcatheter aortic valve replacement: impact of deployment options on paravalvular leakage

Biomechanics and Modeling in Mechanobiology - Transcatheter aortic valve replacement (TAVR) has emerged as an effective alternative to conventional surgical valve replacement in high-risk patients...     

Paxillus orientalis sp. nov. (Paxillaceae,Boletales) from south-western China based on morphological and molecular data and proposal of the new subgenus Alnopaxillus

The new species Paxillus orientalis is reported from Yunnan Province (south-western China). Based on morphological and molecular characters the novel taxon belongs to the sibling, holarctic alder-associated P. rubicundulus complex. Colour pictures of fresh basidiomes and line drawings are provided, accompanied by notes concerning its taxonomic and phylogenetic relationships within the genus. The new subgenus Alnopaxillus is established to accommodate P. rubicundulus and allied undescribed taxa characterized by basidiomes usually associated with Alnus and with a distinctly areolate–squamulose pileal surface.     

Adaptive Evolution in Producing Microtiter Cultivations Generates Genetically Stable Escherichia coli Production Hosts for Continuous Bioprocessing

The production of recombinant proteins usually reduces cell fitness and the growth rate of producing cells. The growth disadvantage favors faster-growing non-producer mutants. Therefore, continuous bioprocessing is hardly feasible in Escherichia coli due to the high escape rate. The stability of E. coli expression systems under long-term production conditions and how metabolic load triggered by recombinant gene expression influences the characteristics of mutations are investigated. Iterated fed-batch-like microbioreactor cultivations are conducted under production conditions. The easy-to-produce green fluorescent protein (GFP) and a challenging antigen-binding fragment (Fab) are used as model proteins, and BL21(DE3) and BL21^Q strains as expression hosts. In comparative whole-genome sequencing analyses, mutations that allowed cells to grow unhindered despite recombinant protein production are identified. A T7 RNA polymerase expression system is only conditionally suitable for long-term cultivation under production conditions. Mutations leading to non-producers occur in either the T7 RNA polymerase gene or the T7 promoter. The host RNA polymerase-based BL21^Q expression system remains stable in the production of GFP in long-term cultivations. For the production of Fab, mutations in lacI of the BL21^Q derivatives have positive effects on long-term stability. The results indicate that adaptive evolution carried out with genome-integrated E. coli expression systems in microtiter cultivations under industrial-relevant production conditions is an efficient strain development tool for production hosts.     

Kin and birth order effects on male child mortality: three East Asian populations, 1716–1945

Human child survival depends on adult investment, typically from parents. However, in spite of recent research advances on kin influence and birth order effects on human infant and child mortality, studies that directly examine the interaction of kin context and birth order on sibling differences in child mortality are still rare. Our study supplements this literature with new findings from large-scale individual-level panel data for three East Asian historical populations from northeast China (1789–1909), northeast Japan (1716–1870), and north Taiwan (1906–1945), where preference for sons and first-borns is common. We examine and compare male child mortality risks by presence/absence of co-resident parents, grandparents, and other kin, as well as their interaction effects with birth order. We apply discrete-time event-history analysis on over 172,000 observations of 69,125 boys aged 1–9 years old. We find that in all three populations, while the presence of parents is important for child survival, it is more beneficial to first/early-borns than to later-borns. Effects of other co-resident kin are however null or inconsistent between populations. Our findings underscore the importance of birth order in understanding how differential parental investment may produce child survival differentials between siblings.     

Lysozyme gene expression and hemocyte behaviour in the Mediterranean mussel, Mytilus galloprovincialis, after injection of various bacteria or temperature stresses

The aim of the present study was to evaluate the expression of the Mytilus galloprovincialis lysozyme gene in different in vivo stress situations, including injection of bacteria Vibrio splendidus LGP32, Vibrio anguillarum or Micrococcus lysodeikticus, as well as heat shock at 30 degrees C and cold stress at 5 degrees C. Injection of V. splendidus LGP32 resulted in: (i) a general down-regulation of lysozyme gene expression, as quantified by Q-PCR; (ii) reduction in the number of circulating hemocytes; (iii) decrease in the percentage of circulating hemocytes expressing lysozyme mRNA which was now restricted to only small cells, as observed by ISH; and (iv) accumulation of hemocytes expressing lysozyme in the muscle sinus where injection took place. Injection of V. anguillarum or M. lysodeikticus induced significant up-regulation of lysozyme gene expression, but only 2-3days post-injection, with no change in the total hemocyte counts but an increased percentage of hemocytes expressing lysozyme mRNA. Neither the control injection of PBS-NaCl nor temperature stress modified the lysozyme expression pattern. Consequently, the hemocyte population appears to be capable of discriminating between stress factors, and even between 2 Vibrio species.     

Behind forest cover changes: is natural regrowth supporting landscape restoration? Findings from Central Italy

In recent years, depopulation and abandonment of traditional practices in the mountainous areas have affected the land use and land cover inducing the modification of the landscape mosaic. These processes have consequently facilitated the forest expansion, sometimes altering the floristic composition of the original vegetation in forests and other wooded lands. Forest expansion processes modified the structure, the stand density and the regeneration capacity of forests, thus altering the ecosystems’ functionality and resilience. These processes can be considered as a form of landscape degradation, which represents an emerging and common issue in the Mediterranean mountainous ecosystems. This study presents an overview of the main landscape dynamics occurring in the last two decades in the “Collemeluccio-Montedimezzo Alto Molise” Man and Biosphere Reserve, located in Central Italy. The results here obtained deeply describe the main effects induced by forest cover changes, such as those related to the crown coverage dynamics-biodiversity linkages, offering a valuable contribution to improve the management and planning in these situations widely replicable to similar contexts.