ABSTRACT
In recent years, ‘multi-omic’ sciences have affected all aspects of fundamental and applied biological research. Yeast taxonomists, though somewhat timidly, have begun to incorporate ...complete genomic sequences into the description of novel taxa, taking advantage of these powerful data to calculate more reliable genetic distances, construct more robust phylogenies, correlate genotype with phenotype and even reveal cryptic sexual behaviors. However, the use of genomic data in formal yeast species descriptions is far from widespread. The present review examines published examples of genome-based species descriptions of yeasts, highlights relevant bioinformatic approaches, provides recommendations for new users and discusses some of the challenges facing the genome-based systematics of yeasts.
The cases in which genome data has accompanied the description of asomycetous and basidiomycetous yeasts are revised including the different methods and approaches used.
ABSTRACT
Genomic studies of yeasts from the wild have increased considerably in the past few years. This revolution has been fueled by advances in high-throughput sequencing technologies and a better ...understanding of yeast ecology and phylogeography, especially for biotechnologically important species. The present review aims to first introduce new bioinformatic tools available for the generation and analysis of yeast genomes. We also assess the accumulated genomic data of wild isolates of industrially relevant species, such as Saccharomyces spp., which provide unique opportunities to further investigate the domestication processes associated with the fermentation industry and opportunistic pathogenesis. The availability of genome sequences of other less conventional yeasts obtained from the wild has also increased substantially, including representatives of the phyla Ascomycota (e.g. Hanseniaspora) and Basidiomycota (e.g. Phaffia). Here, we review salient examples of both fundamental and applied research that demonstrate the importance of continuing to sequence and analyze genomes of wild yeasts.
New genome sequencing technologies together with new bioinformatic tools provide unique insights into the fascinating stories of wild and non-conventional yeast.
This paper presents a study on the mechanical properties of spherical egg-box core sandwich panels subjected to compression. Initial attention focuses on the effect that constraining the core, via ...the introduction of skins, and increasing the thickness of the cell walls has on the compressive properties of GFRP and CFRP structures. Tests were also undertaken on foam-filled samples in order to investigate the influence of additional support on the crushing behaviour of the cores. Low velocity impact tests were subsequently undertaken in order to investigate the rate-sensitivity of these core structures. Finally, blast tests were conducted on the core materials to investigate their response at high strain rates.
It has been shown that constraining the lateral movement of the cores, by bonding composite skins to the upper and lower surfaces, serves to enhance the mechanical properties of the core in compression. In addition, quasi-static compression testing has shown that the compressive strength of the core increases rapidly with increasing cell wall thickness, with effects being more pronounced in the GFRP structures. Tests on foam-filled panels have shown that adding a low density filler to the core serves to enhance the energy-absorbing properties of the GFRP systems. Subsequent tests at dynamic rates of loading have shown that the values of energy absorption were slightly higher than those measured at quasi-static rates, due to rate effects in the failure processes within the composite material. Finally, it has been shown that when subjected to blast loading, extensive crushing of the spherical egg-box was observed, indicating that these structures are capable of absorbing significant energy under this extreme loading condition.
•The compressive strength of the spherical egg-box sandwich panels increases rapidly with increasing cell wall thickness.•Tests on foam-filled panels have shown enhanced energy-absorbing properties.•A load sensitivity effect was noticed at high strain compression.•The extensive crushing of the spherical egg-box was observed under blast loading.
We examine mid- to late Holocene centennial-scale climate variability in Ireland using proxy data from peatlands, lakes and a speleothem. A high degree of between-record variability is apparent in ...the proxy data and significant chronological uncertainties are present. However, tephra layers provide a robust tool for correlation and improve the chronological precision of the records. Although we can find no statistically significant coherence in the dataset as a whole, a selection of high-quality peatland water table reconstructions co-vary more than would be expected by chance alone. A locally weighted regression model with bootstrapping can be used to construct a ‘best-estimate’ palaeoclimatic reconstruction from these datasets. Visual comparison and cross-wavelet analysis of peatland water table compilations from Ireland and Northern Britain show that there are some periods of coherence between these records. Some terrestrial palaeoclimatic changes in Ireland appear to coincide with changes in the North Atlantic thermohaline circulation and solar activity. However, these relationships are inconsistent and may be obscured by chronological uncertainties. We conclude by suggesting an agenda for future Holocene climate research in Ireland.
Birch pollen is a prevalent aeroallergen during the springtime allergy season. In field studies, variable allergen exposure and environmental factors can affect data quality while environmental ...exposure units (EEUs) deliver controlled, standardized, and reproducible allergen exposures.
To inform study design for EEU trials evaluating antiallergic therapies.
In this prospective study, 76 participants with birch allergy experienced 3 exposures to birch pollen: (1) an out-of-season EEU challenge (two 3-hour sessions on consecutive days); (2) a natural seasonal exposure; and (3) an in-season EEU challenge (3-hour exposure for 2 weeks after birch pollen season initiation).
The total nasal symptom score, total ocular symptom score, and total symptom score (TSS = total nasal symptom score plus total ocular symptom score) were assessed every 30 minutes and daily during EEU and natural exposures. A high association between TSSs and day 2 of the out-of-season and in-season EEU challenges was noted, with a good association between the maximum TSS during the natural and in-season EEU challenges, and natural season and day 2 of the out-of-season EEU challenge (P < .001 for all). Participants had higher maximum change from the baseline TSS during day 2 of the out-of-season EEU challenge (12.4) vs the following: (1) first day (9.8); (2) in-season EEU challenge (8.4); and (3) natural seasonal exposure (7.6) (P < .001 for all).
A strong association was seen between the presence of allergy symptoms and exposure to birch pollen in the EEU (maximum change in symptom scores during day 2) and in the field. A hybrid trial design may be useful to demonstrate the clinical efficacy of novel antiallergic therapies requiring fewer participants and shorter timelines and expediting treatment availability.
Anemia is common in older adults and associated with adverse health outcomes in epidemiological studies. A thorough understanding of the complex pathophysiological mechanisms driving anemia in the ...elderly is lacking; but inflammation, iron restriction, and impaired erythroid maturation are thought to influence the phenotype. We hypothesized that interleukin-6 contributes to this anemia, given its pro-inflammatory activities, its ability to induce hepcidin antimicrobial peptide, and its negative impact on several tissues in older adults. We tested this hypothesis by comparing changes in indices of inflammation, iron metabolism and erythropoiesis in aged C57BL/6 mice to aged mice with targeted deletions of interleukin-6 or hepcidin antimicrobial peptide. Circulating neutrophil and monocyte numbers and inflammatory cytokines increased with age. Decline in hemoglobin concentration and red blood cell number indicated that C57BL/6, interleukin-6 knockout mice, and hepcidin antimicrobial peptide knockout mice all demonstrated impaired erythropoiesis by 24 months. However, the interleukin-6 knock out genotype and the hepcidin antimicrobial peptide knock out genotype resulted in improved erythropoiesis in aged mice. Increased erythropoietic activity in the spleen suggested that the erythroid compartment was stressed in aged C57BL/6 mice compared to aged interleukin-6 knockout mice. Our data suggest C57BL/6 mice are an appropriate mammalian model for the study of anemia with age. Furthermore, although interleukin-6 and hepcidin antimicrobial peptide are not required, they can participate in the development of anemia in aging mice, and could be targeted, pre-clinically, with existing interventions to determine the feasibility of such agents for the treatment of anemia in older adults.
1 Exercise Physiology Program, University of Missouri,
Columbia 65211; 2 Nutrition and Consumer Sector, Monsanto
Company, St. Louis 63167; and 3 Department of Biochemistry,
University of Missouri, ...Columbia, Missouri 65211
The purpose of this study was to evaluate the effect of
medium-chain triglycerides (MCT) with and without exercise on
postprandial lipemia (PPL). Subjects were 25 young men and
women. Each subject performed three trials: 1 ) control (fat
meal only, 1.5 g fat/kg) 2 ) MCT (substitution of MCT
oil, 30% of fat calories), and 3 ) MCT + Ex (exercise
12 h before the MCT meal). Before each trial, the subject
underwent consistent dietary preparation. Blood was collected on 2 separate days for baseline measurements of postheparin lipases and, in
each trial, at 0 h (premeal), at 2, 4, 6, and 8 h after the
fat meal for triglycerides and cholesterol ester transfer protein
(CETP), and at 8 h for postheparin lipoprotein lipase (LPL) and
hepatic lipase activities (HL). ANOVA indicated that the partial
substitution of MCT oil to the fat meal did not affect the PPL
response. However, the PPL was significantly lower after the MCT + Ex trial vs. the other trials. LPL activity was significantly elevated
after all trials compared with baseline, whereas HL was lower in the
MCT + Ex trial only. CETP mass was significantly lower at 4 and
8 h than 0 h during all trials but relatively higher in the
MCT + Ex trial vs. the nonexercise trials. These results suggest
that MCT does not affect the TG response to a fat meal. LPL and CETP
are affected by a fat meal with or without exercise, but HL is affected
only when exercise is included.
cholesterol ester transfer protein; exercise training; hepatic
lipase activity; lipoprotein lipase activity; triglycerides
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