102 research outputs found
Induction of Mutants with Ectopic Expression of Condensed Tannins
Leaves of 47,000 Lotus japonicus plants were screened using a butanol:HCl histochemical test to select “gain of function” mutants. These plants were progeny from L. japonicus lines which were transformed with T-DNA constructs containing either the maize Ds or Ac transposon (Thykjaer et al., 1995). Among 21 putative leaf tannin mutants, five (tan1-5) were characterized for synthesis of condensed tannins, leucocyanidin reductase activity and the presence of Ac and the selectable marker gene, nptII . A range of leaf tannin content among other Lotus species was also characterized
Morphology, carbohydrate distribution, gene expression, and enzymatic activities related to cell wall hydrolysis in four barley varieties during simulated malting
Many biological processes, such as cell wall hydrolysis and the mobilisation of nutrient reserves from the starchy endosperm, require stringent regulation to successfully malt barley (Hordeum vulgare) grain in an industrial context. Much of the accumulated knowledge defining these events has been collected from individual, unrelated experiments, and data have often been extrapolated from Petri dish germination, rather than malting, experiments. Here, we present comprehensive morphological, biochemical, and transcript data from a simulated malt batch of the three elite malting cultivars Admiral, Navigator, and Flagship, and the feed cultivar Keel. Activities of lytic enzymes implicated in cell wall and starch depolymerisation in germinated grain have been measured, and transcript data for published cell wall hydrolytic genes have been provided. It was notable that Flagship and Keel exhibited generally similar patterns of enzyme and transcript expression, but exhibited a few key differences that may partially explain Flagship's superior malting qualities. Admiral and Navigator also showed matching expression patterns for these genes and enzymes, but the patterns differed from those of Flagship and Keel, despite Admiral and Navigator having Keel as a common ancestor. Overall (1,3;1,4)-β-glucanase activity differed between cultivars, with lower enzyme levels and concomitantly higher amounts of (1,3;1,4)-β-glucan in the feed variety, Keel, at the end of malting. Transcript levels of the gene encoding (1,3;1,4)-β-glucanase isoenzyme EI were almost three times higher than those encoding isoenzyme EII, suggesting a previously unrecognised importance for isoenzyme EI during malting. Careful morphological examination showed that scutellum epithelial cells in mature dry grain are elongated but expand no further as malting progresses, in contrast to equivalent cells in other cereals, perhaps demonstrating a morphological change in this critical organ over generations of breeding selection. Fluorescent immuno-histochemical labelling revealed the presence of pectin in the nucellus and, for the first time, significant amounts of callose throughout the starchy endosperm of mature grain.Natalie S. Betts, Laura G. Wilkinson, Shi F. Khor, Neil J. Shirley, Finn Lok, Birgitte Skadhauge, Rachel A. Burton, Geoffrey B. Fincher and Helen M. Collin
CPT Violation and the Nature of Neutrinos
In order to accommodate the neutrino oscillation signals from the solar,
atmospheric, and LSND data, a sterile fourth neutrino is generally invoked,
though the fits to the data are becoming more and more constrained. However, it
has recently been shown that the data can be explained with only three
neutrinos, if one invokes CPT violation to allow different masses and mixing
angles for neutrinos and antineutrinos. We explore the nature of neutrinos in
such CPT-violating scenarios. Majorana neutrino masses are allowed, but in
general, there are no longer Majorana neutrinos in the conventional sense.
However, CPT-violating models still have interesting consequences for
neutrinoless double beta decay. Compared to the usual case, while the larger
mass scale (from LSND) may appear, a greater degree of suppression can also
occur.Comment: 10 pages, 1 figur
Effect of indomethacin on S. typhimurium and cholera toxin-induced fluid accumulation in pig jejunum
We have investigated the influence of prostaglandins (PGs) on the Salmonella typhimurium (St) and cholera toxin (CT)-induced fluid accumulation in jejunum of 9-10 weeks (18-20 kg) old female pigs. St (1010 colony forming units) and CT (56/ig) were instilled in separated tiedoff loops for 8 hours. Before instillation, and again after 4 hours, pigs were given an intravenous dose of the cyclooxygenase and prostaglandin synthesis inhibitor, indomethacin, or saline alone (control). In the St-loops indomethacin had no effect on the fluid accumulation, 9.1 ± 1.3 vs 8.2±0.5 mg fluid/mg loop dry weight, whereas in CT-Ioops, indomethacin reduced fluid accumulation significantly from 35±2 to 22±3 mg fluid/mg loop dry weight (P\u3c0.05). Our preliminary results indicate that PGs are not involved in St-induced fluid accumulation in pig jejunum, which is in contrast to the case in CT -induced fluid accumulation
Prevalence of Obesity-Related Disease in a Danish Population – The Results of an Algorithm-Based Screening Program
Claus B Juhl,1– 4 Else Marie Bladbjerg,3,5 Bibi Gram,3 Torben Knudsen,3,6 Mette Munk Lauridsen,3,6 Niels-Peter Brøchner Nygaard,1,3,7 Nina Drøjdahl Ryg,1,2,4 Lars Skadhauge,3,8 Anna-Marie Bloch Münster3,5 1Department of Endocrinology, University Hospital of Southern Denmark, Esbjerg, Denmark; 2Steno Diabetes Center Odense, University Hospital of Southern Denmark, Odense, Denmark; 3University of Southern Denmark, Department of Regional Health Research, Odense, Denmark; 4OPEN, Open Patient Data Explorative, Odense University Hospital, Odense, Denmark; 5Department of Clinical Biochemistry, University Hospital of Southern Denmark, Esbjerg, Denmark; 6Department of Gastroenterology, University Hospital of Southern Denmark, Esbjerg, Denmark; 7Department of Neurology, University Hospital of Southern Denmark, Esbjerg, Denmark; 8Department of Occupational Medicine, University Hospital of Southern Denmark, Esbjerg, DenmarkCorrespondence: Claus B Juhl, Department of Endocrinology, University Hospital Southern Denmark, Esbjerg, DK-6700, Denmark, Tel +45 6086 7172, Email [email protected]: The prevalence of obesity continues to rise. People with obesity are at increased risk of several diseases. We tested an algorithm-based screening program for people with a BMI above 30 kg/m2 and present data on the prevalence of previously undiagnosed obesity-related diseases.Patients and Methods: Seven hundred and sixty-nine persons with BMI > 30 kg/m2 and age 18– 60 years were screened for diabetes (assessed by glycosylated hemoglobin and oral glucose tolerance test at HbA1c 43– 48 mmol/mol), sleep apnea (screened by questionnaires and assessed by cardiorespiratory monitoring at indication of sleep disorder), liver steatosis or liver fibrosis (assessed by biochemistry and fibroscan) and arterial hypertension (assessed by both office and 24-hour blood pressure measurement). A reference group of people with a BMI of 18.5– 29.9 kg/m2 was established.Results: Of those referred, 73.0% were women. We identified new diabetes in 4.2%, prediabetes in 9.1%, moderate-to-severe sleep apnea in 25.1%, increased liver fat and increased liver stiffness in 68.1% and 17.4%, respectively, and hypertension or masked hypertension in 19.0%. The prevalence of diseases was much higher among men and increased with BMI. Except for hypertension, we found few participants with undiagnosed disease in the reference group.Conclusion: An algorithm-based screening program is feasible and reveals undiagnosed obesity-related disease in a large proportion of the participants. The disproportional referral pattern calls for a tailored approach aiming to include more men with obesity.Trial Registration: Inclusion of the non-obese group was approved by the Scientific Ethics Committee of The Region of Southern Denmark (project identification number: S-20210091), and the study was reported at clinicaltrials.gov (NCT05176132).Plain Language Summary: The number of people with obesity is going up, and they are at a higher risk for various diseases. We tested a screening program for people referred with a BMI over 30 kg/m2 and presented the prevalence of diseases related to obesity. We screened 769 people aged 18 to 60 years with a BMI over 30 kg/m2 for diabetes (biochemistry and glucose tolerance test), sleep apnea (both questionnaires and home monitoring), liver disease (biochemistry and liver scan) and high blood pressure (office and 24-hour readings). We also tested a reference group of people with BMI 18.5-30 kg/m2. Among those screened, 73.0% were women. We found new cases of diabetes in 4.2%, prediabetes in 9.1%, sleep apnea in 25.1%, increased liver fat in 68.1%, increased liver stiffness in 17.4%, and hypertension or masked hypertension in 19.0%. The diseases were more common in men and increased with both higher BMI and age. Except for hypertension, we found few cases in the reference groups. The screening program uncovered undiagnosed obesity-related diseases in a large group of individuals. The uneven distribution of referrals suggests we need a customized approach to include more men with obesity.Keywords: diabetes, pre-diabetes, sleep apnea, metabolic dysfunction-associated steatotic liver disease, hypertensio
LHC signals for neutrino mass model in bilinear R-parity violating mAMSB
We investigate a neutrino mass model in which the neutrino data is accounted
for by bilinear R-parity violating supersymmetry with anomaly mediated
supersymmetry breaking. We focus on the CERN Large Hadron Collider (LHC)
phenomenology, studying the reach of generic supersymmetry search channels with
leptons, missing energy and jets. A special feature of this model is the
existence of long lived neutralinos and charginos which decay inside the
detector leading to detached vertices. We demonstrate that the largest reach is
obtained in the displaced vertices channel and that practically all of the
reasonable parameter space will be covered with an integrated luminosity of 10
fb-1. We also compare the displaced vertex reaches of the LHC and Tevatron.Comment: 27 page
Low-cost cross-taxon enrichment of mitochondrial DNA using in-house synthesised RNA probes
Hybridization capture with in-solution oligonucleotide probes has quickly become the preferred method for enriching specific DNA loci from degraded or ancient samples prior to high-throughput sequencing (HTS). Several companies synthesize sets of probes for in-solution hybridization capture, but these commercial reagents are usually expensive. Methods for economical in-house probe synthesis have been described, but they do not directly address one of the major advantages of commercially synthesised probes: that probe sequences matching many species can be synthesised in parallel and pooled. The ability to make "phylogenetically diverse" probes increases the cost-effectiveness of commercial probe sets, as they can be used across multiple projects (or for projects involving multiple species). However, it is labour-intensive to replicate this with in-house methods, as template molecules must first be generated for each species of interest. While it has been observed that probes can be used to enrich for phylogenetically distant targets, the ability of this effect to compensate for the lack of phylogenetically diverse probes in in-house synthesised probe sets has not been tested. In this study, we present a refined protocol for in-house RNA probe synthesis and evaluated the ability of probes generated using this method from a single species to successfully enrich for the target locus in phylogenetically distant species. We demonstrated that probes synthesized using long-range PCR products from a placental mammal mitochondrion (Bison spp.) could be used to enrich for mitochondrial DNA in birds and marsupials (but not plants). Importantly, our results were obtained for approximately a third of the cost of similar commercially available reagents.Stephen M. Richards, Nelli Hovhannisyan, Matthew Gilliham, Joshua Ingram, Birgitte Skadhauge, Holly Heiniger, Bastien Llamas, Kieren J. Mitchell, Julie Meachen, Geoffrey B. Fincher, Jeremy J. Austin, Alan Coope
Status of the CPT Violating Interpretations of the LSND Signal
We study the status of the CPT violating neutrino mass spectrum which has
been proposed to simultaneously accommodate the oscillation data from LSND,
KamLAND, atmospheric and solar neutrino experiments, as well as the
non-observation of anti-neutrino disappearance in short-baseline reactor
experiments. We perform a three-generation analysis of the global data with the
aim of elucidating the viability of this solution. We find no compatibility
between the results of the oscillation analysis of LSND and all-but-LSND data
sets below 3 CL. Furthermore, the global data without LSND show no
evidence for CPT violation: the best fit point of the all-but-LSND analysis
occurs very close to a CPT conserving scenario.Comment: Improved version, to appear in Phys. Rev. D, 16 pages, 5 figure
Transcriptional and biochemical analyses of gibberellin expression and content in germinated barley grain
Mobilization of reserves in germinated cereal grains is critical for early seedling vigour, global crop productivity and hence food security. Gibberellins (GAs) are central to this process. We have developed a spatio-temporal model that describes the multifaceted mechanisms of GA regulation in germinated barley grain. The model was generated using RNA-seq transcript data from tissues dissected from intact, germinated grain, which closely match measurements of GA hormones and their metabolites in those tissues. The data show that successful grain germination is underpinned by high concentrations of GA precursors in ungerminated grain, the use of independent metabolic pathways for the synthesis of several bioactive GAs during germination, and a capacity to abort bioactive GA biosynthesis. The most abundant bioactive form is GA₁, which is synthesized in the scutellum as a glycosyl conjugate that diffuses to the aleurone, where it stimulates de novo synthesis of a GA₃ conjugate and GA₄. Synthesis of bioactive GAs in the aleurone provides a mechanism that ensures the hormonal signal is relayed from the scutellum to the distal tip of the grain. The transcript dataset of 33,421 genes used to define GA metabolism is available as a resource to analyse other physiological processes in germinated grain.Natalie S. Betts, Christoph Dockter, Oliver Berkowitz, Helen M. Collins, Michelle Hooi, Qiongxian Lu, Rachel A. Burton, Vincent Bulone, Birgitte Skadhauge, James Whelan, and Geoffrey B. Finche
Disentangling hydroxynitrile glucoside biosynthesis in a barley (Hordeum vulgare) metabolon provides access to elite malting barleys for ethyl carbamate-free whisky production
Barley produces several specialized metabolites, including five α-, β-, and γ-hydroxynitrile glucosides (HNGs). In malting barley, presence of the α-HNG epiheterodendrin gives rise to undesired formation of ethyl carbamate in the beverage production, especially after distilling. Metabolite-GWAS identified QTLs and underlying gene candidates possibly involved in the control of the relative and absolute content of HNGs, including an undescribed MATE transporter. By screening 325 genetically diverse barley accessions, we discovered three H. vulgare ssp. spontaneum (wild barley) lines with drastic changes in the relative ratios of the five HNGs. Knock-out (KO)-lines, isolated from the barley FIND-IT resource and each lacking one of the functional HNG biosynthetic genes (CYP79A12, CYP71C103, CYP71C113, CYP71U5, UGT85F22 and UGT85F23) showed unprecedented changes in HNG ratios enabling assignment of specific and mutually dependent catalytic functions to the biosynthetic enzymes involved. The highly similar relative ratios between the five HNGs found across wild and domesticated barley accessions indicate assembly of the HNG biosynthetic enzymes in a metabolon, the functional output of which was reconfigured in the absence of a single protein component. The absence or altered ratios of the five HNGs in the KO-lines did not change susceptibility to the fungal phytopathogen Pyrenophora teres causing net blotch. The study provides a deeper understanding of the organization of HNG biosynthesis in barley and identifies a novel, single gene HNG-0 line in an elite spring barley background for direct use in breeding of malting barley, eliminating HNGs as a source of ethyl carbamate formation in whisky production.</p
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