Selection of favorable alleles of genes controlling flowering and senescence improves malt barley quality

Molecular Breeding - Maize amylose is a type of high value-added starch used for medical, food, and chemical applications. Mutations in the starch branching enzyme (SBEIIb), with recessive ae...     

Pixel by pixel: real-time observation and quantification of passive flotation speeds of three common equine endoparasite egg types

The efficacy of anthelmintic treatments against populations of endoparasites infecting livestock throughout the world is decreasing. To mitigate this, the use of fecal egg counts is recommended to determine both the necessity, and to ensure the appropriate choice, of anthelmintic treatment. Traditionally, and in order to facilitate easier identification and/or enumeration, samples are analysed after separating eggs from other fecal particulates by exposing them to a solution with a density higher than that of the eggs, but lower than the remaining fecal contents. While many parasite egg flotation protocols exist, little is known about the characteristics of these eggs with respect to their movement through a flotation solution. In this study, we have demonstrated a novel method for the observation and quantification of microscopic (65–100 µm) objects as they experience unassisted flotation. This also represents, to our knowledge for the first time, that the flotation of parasite eggs has been observed and their movement characteristics quantified as they float through solution. Particle tracking and video analysis software were utilised to automatically detect and track the movement of individual eggs as they floated. Three 30 s videos and one 2 min video of each egg type were analysed. If the first 30 s of video were discounted, the differences in mean flotation speed among all videos was statistically significant between egg types (P = 0.0004). Strongyle type eggs (n = 201) moved the fastest with a mean 51.08 µm/s (95% confidence interval: 47.54–54.62). This was followed by Parascaris spp. (n = 131) and Anoplocephala perfoliata eggs (n = 322), with mean speeds of 44.43 µm/s (95% confidence interval: 39.47–49.4) and 31.11 µm/s (95% confidence interval: 29.6–32.61), respectively. This method for evaluating the mean speed of passive flotation may represent a first step towards further optimizing fecal egg flotation and be of interest to parasitologists and veterinary practitioners.     

Livestock disturbances in Mediterranean temporary ponds: A mesocosm experiment with sheep manure and simulated trampling

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The role of Ubiquitination in Apoptosis and Necroptosis

Cell death pathways have evolved to maintain tissue homoeostasis and eliminate potentially harmful cells from within an organism, such as cells with damaged DNA that could lead to cancer. Apoptosis, known to eliminate cells in a predominantly non-inflammatory manner, is controlled by two main branches, the intrinsic and extrinsic apoptotic pathways. While the intrinsic pathway is regulated by the Bcl-2 family members, the extrinsic pathway is controlled by the Death receptors, members of the tumour necrosis factor (TNF) receptor superfamily. Death receptors can also activate a pro-inflammatory type of cell death, necroptosis, when Caspase-8 is inhibited. Apoptotic pathways are known to be tightly regulated by post-translational modifications, especially by ubiquitination. This review discusses research on ubiquitination-mediated regulation of apoptotic signalling. Additionally, the emerging importance of ubiquitination in regulating necroptosis is discussed.Subject terms: Protein-protein interaction networks, Deubiquitylating enzymes, Ubiquitin ligases, Ubiquitylation     

Anti-Inflammatory Effects of Resveratrol on Human Retinal Pigment Cells and a Myopia Animal Model

Resveratrol is a key component of red wine and other grape products. Recent studies have characterized resveratrol as a polyphenol, and shown its beneficial effects on cancer, metabolism, and infection. This study aimed to obtain insights into the biological effects of resveratrol on myopia. To this end, we examined its anti-inflammatory influence on human retinal pigment epithelium cells and in a monocular form deprivation (MFD)-induced animal model of myopia. In MFD-induced myopia, resveratrol increased collagen I level and reduced the expression levels of matrix metalloproteinase (MMP)2, transforming growth factor (TGF)-β, and nuclear factor (NF)-κB expression levels. It also suppressed the levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β. Resveratrol exhibited no significant cytotoxicity in ARPE-19 cells. Downregulation of inflammatory cytokine production, and inhibition of AKT, c-Raf, Stat3, and NFκB phosphorylation were observed in ARPE-19 cells that were treated with resveratrol. In conclusion, the findings suggest that resveratrol inhibits inflammatory effects by blocking the relevant signaling pathways, to ameliorate myopia development. This may make it a natural candidate for drug development for myopia.     

Reconstitution of EBV-directed T cell immunity by adoptive transfer of peptide-stimulated T cells in a patient after allogeneic stem cell transplantation for AITL

Reconstitution of the T cell repertoire after allogeneic stem cell transplantation is a long and often incomplete process. As a result, reactivation of Epstein-Barr virus (EBV) is a frequent complication that may be treated by adoptive transfer of donor-derived EBV-specific T cells. We generated donor-derived EBV-specific T cells by stimulation with peptides representing defined epitopes covering multiple HLA restrictions. T cells were adoptively transferred to a patient who had developed persisting high titers of EBV after allogeneic stem cell transplantation for angioimmunoblastic T-cell lymphoma (AITL). T cell receptor beta (TCRβ) deep sequencing showed that the T cell repertoire of the patient early after transplantation (day 60) was strongly reduced and only very low numbers of EBV-specific T cells were detectable. Manufacturing and in vitro expansion of donor-derived EBV-specific T cells resulted in enrichment of EBV epitope-specific, HLA-restricted T cells. Monitoring of T cell clonotypes at a molecular level after adoptive transfer revealed that the dominant TCR sequences from peptide-stimulated T cells persisted long-term and established an EBV-specific TCR clonotype repertoire in the host, with many of the EBV-specific TCRs present in the donor. This reconstituted repertoire was associated with immunological control of EBV and with lack of further AITL relapse.     

Community structure of ectomycorrhizal fungi in a Pinus muricata forest: minimal overlap between the mature forest and resistant propagule communities

We have investigated colonization strategies by comparing the abundance and frequency of ectomycorrhizal fungal species on roots in a mature Pinus muricata forest with those present as resistant propagules colonizing potted seedlings grown in the same soil samples. Thirty-seven fungal species were distinguished by internal transcribed spacer (ITS) restriction fragment length polymorphisms (RFLPs); most were identified to species level by sporocarp RFLP matches or to genus/family level by using sequence databases for the mitochondrial and nuclear large-subunit rRNA genes. The below-ground fungal community found in the mature forest contrasted markedly with the resistant propagule community, as only four species were found in both communities. The dominant species in the mature forest were members of the Russulaceae, Thelephorales and Amanitaceae. In contrast, the resistant propagule community was dominated by Rhizopogon species and by species of the Ascomycota. Only one species, Tomentella sublilacina (Thelephorales), was common in both communities. The spatial distribution of mycorrhizae on mature roots and propagules in the soil differed among the dominant species. For example, T. sublilacina mycorrhizae exhibited a unique bias toward the organic horizons, Russula brevipes mycorrhizae were denser and more clumped than those of other species and Cenococcum propagules were localized, whereas R. subcaerulescens propagules were evenly distributed. We suggest that species differences in resource preferences and colonization strategies, such as those documented here, contribute to the maintenance of species richness in the ectomycorrhizal community.     

Evaluation of an in vitro coculture model for the blood-brain barrier: Comparison of human umbilical vein endothelial cells (ECV304) and rat glioma cells (C6) from two commercial sources

Summary Cocultures of human umbilical vein endothelial cells (ECV304) and rat glioma cells (C6) from two commercial sources, American Type Culture Collection and European Collection of Animal Cell Cultures, were evaluated as an in vitro model for the blood-brain barrier. Monolayers of endothelial cells grown in the presence or absence of glial cells were examined for transendothelial electrical resistance, sucrose permeability, morphology, multidrug resistance-associated protein expression, and P-glycoprotein expression and function. Coculture of glial cells with endothelial cells increased electrical resistance and decreased sucrose permeability across European endothelial cell monolayers, but had no effect on American endothelial cells. Coculture of European glial cells with endothelial cells caused cell flattening and decreased cell stacking with both European and American endothelial cells. No P-glycoprotein or multidrug resistance-associated protein was immunodetected in endothelial cells grown in glial cell-conditioned medium. Functional P-glycoprotein was demonstrated in American endothelial cells selected in vinblastine-containing medium over eight passages, but these cells did not form a tight endothelium. In conclusion, while European glial cells confer blood-brain barrier-like morphology and barrier integrity to European endothelial cells in coculture, the European endothelial-glial cell coculture model does not express P-glycoprotein, normally found at the blood-brain barrier. Further, the response of endothelial cells to glial factors was dependent on cell source, implying heterogeneity among cell populations. On the basis of these observations, the umbilical vein endothelial cell-glial cell coculture model does not appear to be a viable model for predicting blood-brain barrier penetration of drug molecules.     

Alternative sulfonylurea receptor expression defines metabolic sensitivity of K-ATP channels in dopaminergic midbrain neurons

ATP-sensitive potassium (K-ATP) channels couple the metabolic state to cellular excitability in various tissues. Several isoforms of the K-ATP channel subunits, the sulfonylurea receptor (SUR) and inwardly rectifying K channel (Kir6.X), have been cloned, but the molecular composition and functional diversity of native neuronal K-ATP channels remain unresolved. We combined functional analysis of K-ATP channels with expression profiling of K-ATP subunits at the level of single substantia nigra (SN) neurons in mouse brain slices using an RT-multiplex PCR protocol. In contrast to GABAergic neurons, single dopaminergic SN neurons displayed alternative co-expression of either SUR1, SUR2B or both SUR isoforms with Kir6.2. Dopaminergic SN neurons expressed alternative K-ATP channel species distinguished by significant differences in sulfonylurea affinity and metabolic sensitivity. In single dopaminergic SN neurons, co-expression of SUR1 + Kir6.2, but not of SUR2B + Kir6.2, correlated with functional K-ATP channels highly sensitive to metabolic inhibition. In contrast to wild-type, surviving dopaminergic SN neurons of homozygous weaver mouse exclusively expressed SUR1 + Kir6.2 during the active period of dopaminergic neurodegeneration. Therefore, alternative expression of K-ATP channel subunits defines the differential response to metabolic stress and constitutes a novel candidate mechanism for the differential vulnerability of dopaminergic neurons in response to respiratory chain dysfunction in Parkinson's disease.