Traditional farm‐based products based on livestock are one of the main contributors to greenhouse gas emissions. Cultivated meat is an alternative that mimics animal meat, being produced in a ...bioreactor under controlled conditions rather than through the slaughtering of animals. The first step in the production of cultivated meat is the generation of sufficient reserves of starting cells. In this study, bovine adipose‐derived stem cells (bASCs) were used as starting cells due to their ability to differentiate towards both fat and muscle, two cell types found in meat. A bioprocess for the expansion of these cells on microcarriers in spinner flasks was developed. Different cell seeding densities (1,500, 3,000, and 6,000 cells/cm2) and feeding strategies (80%, 65%, 50%, and combined 80%/50% medium exchanges) were investigated. Cell characterization was assessed pre‐ and postbioprocessing to ensure that bioprocessing did not negatively affect bASC quality. The best growth was obtained with the lowest cell seeding density (1,500 cells/cm2) with an 80% medium exchange performed (p < .0001) which yielded a 28‐fold expansion. The ability to differentiate towards adipogenic, osteogenic, and chondrogenic lineages was retained postbioprocessing and no significant difference (p > .5) was found in clonogenicity pre‐ or postbioprocessing in any of the feeding regimes tested.
The first step in producing cultivated meat is expansion of starting cells. Bovine adipose‐derived stem cells can be used as starting cells as they can form fat and muscle – 2 cell types present in meat. Hanga and co‐workers have developed a bioprocess for the scalable expansion of these cells and investigated the effect of different cell seeding densities and feeding regimes on cell expansion. The optimal bioprocess yielded a 28‐fold increase in pre‐processing quality cells in 10 days.
The strength of phylogenetic signal in extinction risk can give insight into the mechanisms behind species' declines. Nevertheless, no existing measure of phylogenetic pattern in a binary trait, such ...as extinction-risk status, measures signal strength in a way that can be compared among data sets. We developed a new measure for phylogenetic signal of binary traits, D, which simulations show gives robust results with data sets of more than 50 species, even when the proportion of threatened species is low. We applied D to the red-list status of British birds and the world's mammals and found that the threat status for both groups exhibited moderately strong phylogenetic clumping. We also tested the hypothesis that the phylogenetic pattern of species threatened by harvesting will be more strongly clumped than for those species threatened by either habitat loss or invasive species because the life-history traits mediating the effects of harvesting show strong evolutionary pattern. For mammals, our results supported our hypothesis; there was significant but weaker phylogenetic signal in the risk caused by the other two drivers (habitat loss and invasive species). We conclude that D is likely to be a useful measure of the strength of phylogenetic pattern in many binary traits.
Glycosylation of proteins is an essential process in all eukaryotes and a great diversity in types of protein glycosylation exists in animals, plants and microorganisms. Mucin-type O-glycosylation, ...consisting of glycans attached via O-linked N-acetylgalactosamine (GalNAc) to serine and threonine residues, is one of the most abundant forms of protein glycosylation in animals. Although most protein glycosylation is controlled by one or two genes encoding the enzymes responsible for the initiation of glycosylation, i.e. the step where the first glycan is attached to the relevant amino acid residue in the protein, mucin-type O-glycosylation is controlled by a large family of up to 20 homologous genes encoding UDP-GalNAc:polypeptide GalNAc-transferases (GalNAc-Ts) (EC 2.4.1.41). Therefore, mucin-type O-glycosylation has the greatest potential for differential regulation in cells and tissues. The GalNAc-T family is the largest glycosyltransferase enzyme family covering a single known glycosidic linkage and it is highly conserved throughout animal evolution, although absent in bacteria, yeast and plants. Emerging studies have shown that the large number of genes (GALNTs) in the GalNAc-T family do not provide full functional redundancy and single GalNAc-T genes have been shown to be important in both animals and human. Here, we present an overview of the GalNAc-T gene family in animals and propose a classification of the genes into subfamilies, which appear to be conserved in evolution structurally as well as functionally.
ABSTRACT
The use of phylogenies in ecology is increasingly common and has broadened our understanding of biological diversity. Ecological sub‐disciplines, particularly conservation, community ecology ...and macroecology, all recognize the value of evolutionary relationships but the resulting development of phylogenetic approaches has led to a proliferation of phylogenetic diversity metrics. The use of many metrics across the sub‐disciplines hampers potential meta‐analyses, syntheses, and generalizations of existing results. Further, there is no guide for selecting the appropriate metric for a given question, and different metrics are frequently used to address similar questions. To improve the choice, application, and interpretation of phylo‐diversity metrics, we organize existing metrics by expanding on a unifying framework for phylogenetic information.
Generally, questions about phylogenetic relationships within or between assemblages tend to ask three types of question: how much; how different; or how regular? We show that these questions reflect three dimensions of a phylogenetic tree: richness, divergence, and regularity. We classify 70 existing phylo‐diversity metrics based on their mathematical form within these three dimensions and identify ‘anchor’ representatives: for α‐diversity metrics these are PD (Faith's phylogenetic diversity), MPD (mean pairwise distance), and VPD (variation of pairwise distances). By analysing mathematical formulae and using simulations, we use this framework to identify metrics that mix dimensions, and we provide a guide to choosing and using the most appropriate metrics. We show that metric choice requires connecting the research question with the correct dimension of the framework and that there are logical approaches to selecting and interpreting metrics. The guide outlined herein will help researchers navigate the current jungle of indices.
Identifying chemical compounds is essential in several areas of science and engineering. Laser-based techniques are promising for autonomous compound detection because the optical response of ...materials encodes enough electronic and vibrational information for remote chemical identification. This has been exploited using the fingerprint region of infrared absorption spectra, which involves a dense set of absorption peaks that are unique to individual molecules, thus facilitating chemical identification. However, optical identification using visible light has not been realized. Using decades of experimental refractive index data in the scientific literature of pure organic compounds and polymers over a broad range of frequencies from the ultraviolet to the far-infrared, we develop a machine learning classifier that can accurately identify organic species based on a single-wavelength dispersive measurement in the visible spectral region, away from absorption resonances. The optical classifier proposed here could be applied to autonomous material identification protocols and applications.
A series of N-mono- and N,N-disubstituted dithiocarbamates have been investigated as inhibitors of three β-carbonic anhydrases (CAs, EC 4.2.1.1) from the fungal pathogens Cryptococcus neoformans, ...Candida albicans and Candida glabrata, that is, Can2, CaNce103 and CgNce103, respectively. These enzymes were inhibited with efficacies between the subnanomolar to the micromolar range, depending on the substitution pattern at the nitrogen atom from the dithiocarbamate zinc-binding group. This new class of β-CA inhibitors may have the potential for developing antifungal agents with a diverse mechanism of action compared to the clinically used drugs for which drug resistance was reported, and may also explain the efficacy of dithiocarbamates as agricultural antifungal agents.
Climate models predict greater increases in nighttime temperature in the future. The impacts of high nighttime temperature on wheat (Triticum aestivum L.) are not well understood. Objectives of this ...research were to quantify the impact of high nighttime temperatures during reproductive development on phenology, physiological, vegetative, and yield traits of wheat. Two spring wheat cultivars (Pavon-76 and Seri-82) were grown at optimum temperatures (day/night, 24/14°C; 16/8 h light/dark photoperiod) from sowing to booting. Thereafter, plants were exposed to four different nighttime temperatures (14, 17, 20, 23°C) until maturity. The daytime temperature was 24°C across all treatments. There were significant influences of high nighttime temperatures on physiological, growth, and yield traits, but no cultivar or cultivar by temperature interactions were observed. High nighttime temperatures (>14°C) decreased photosynthesis after 14 d of stress. Grain yields linearly decreased with increasing nighttime temperatures, leading to lower harvest indices at 20 and 23°C. High nighttime temperature (> or =20°C) decreased spikelet fertility, grains per spike, and grain size. Compared to the control (14°C), grain filling duration was decreased by 3 and 7 d at night temperatures of 20 and 23°C, respectively. High nighttime temperature increased the expression of chloroplast protein synthesis elongation factor in both cultivars suggesting possible involvement of this protein in plant response to stress.
Abstract
Virulence of the fungal human pathogen Candida albicans is also attributed to its ability to switch reversibly between yeast and hyphal growth forms. Morphogenesis in this yeast is ...influenced by the composition of the environment, activating sensors, which consequently play an important role in fungal pathogenicity. This review summarizes some of the main environmental sensors, their ligands and downstream signaling pathways in C. albicans. We will focus on proteins localized in the plasma membrane and on the interaction between cells and their environment. This will underline the convergence of several environmental signals onto the mitogen-activated protein kinase and protein kinase A pathways.
An Update of Wallace's Zoogeographic Regions of the World Holt, Ben G.; Lessard, Jean-Philippe; Borregaard, Michael K. ...
Science (American Association for the Advancement of Science),
01/2013, Letnik:
339, Številka:
6115
Journal Article
Recenzirano
Modern attempts to produce biogeographic maps focus on the distribution of species, and the maps are typically drawn without phylogenetic considerations. Here, we generate a global map of ...zoogeographic regions by combining data on the distributions and phylogenetic relationships of 21,037 species of amphibians, birds, and mammals. We identify 20 distinct zoogeographic regions, which are grouped into 11 larger realms. We document the lack of support for several regions previously defined based on distributional data and show that spatial turnover in the phylogenetic composition of vertebrate assemblages is higher in the Southern than in the Northern Hemisphere. We further show that the integration of phylogenetic information provides valuable insight on historical relationships among regions, permitting the identification of evolutionarily unique regions of the world.
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