48 research outputs found
Visceral, subcutaneous abdominal adiposity and liver fat content distribution in normal glucose tolerance, impaired fasting glucose and/or impaired glucose tolerance
Q1Q1Objectives:
To examine the specific distribution of liver fat content, visceral and subcutaneous adiposity in normal glucose tolerance (NGT/NGT), isolated impaired fasting glucose (iIFG), isolated impaired glucose tolerance (iIGT) and combined conditions (IFG+IGT), as well as with newly diagnosed type 2 diabetes (nT2D).
Design:
Multicenter, international observational study: cross-sectional analysis.
Subjects:
Two thousand five hundred and fifteen patients (50.0% women, 54.5% non-Caucasian) without previously known diabetes were recruited from 29 countries. Abdominal fat distribution was measured by computed tomography (CT). Liver fat was estimated using the CT-liver mean attenuation.
Results:
Compared with NGT/NGT patients, increased visceral adiposity was found in iIFG, iIGT, IFG+IGT and nT2D; estimated liver fat progressively increased across these conditions. A one-s.d. increase in visceral adiposity was associated with an increased risk of having iIFG (men: odds ratio (OR) 1.41 (95% confidence interval (CI) 1.15–1.74), women: OR 1.62 (1.29–2.04)), iIGT (men: OR 1.59 (1.15–2.01), women: OR 1.30 (0.96–1.76)), IFG+IGT (men: OR 1.64 (1.27–2.13), women: OR 1.83 (1.36–2.48)) and nT2D (men: OR 1.80 (1.35–2.42), women: OR 1.73 (1.25–2.41)). A one-s.d. increase in estimated liver fat was associated with iIGT (men: OR 1.46 (1.12–1.90), women: OR 1.81 (1.41–2.35)), IFG+IGT (men: OR 1.42 (1.14–1.77), women: OR 1.74 (1.35–2.26)) and nT2D (men: OR 1.77 (1.40–2.27), women: OR 2.38 (1.81–3.18)). Subcutaneous abdominal adipose tissue showed an inverse relationship with nT2D in women (OR 0.63 (0.45–0.88)).
Conclusions:
Liver fat was associated with iIGT but not with iIFG, whereas visceral adiposity was associated with both. Liver fat and visceral adiposity were associated with nT2D, whereas subcutaneous adiposity showed an inverse relationship with nT2D in women
and Oxygen Stoichiometry: Structure, Resistivity, Fermi Surface Topology and Normal State Properties
(2212) single crystal samples
were studied using transmission electron microscopy (TEM), plane
() and axis () resistivity, and high resolution
angle-resolved ultraviolet photoemission spectroscopy (ARUPS). TEM reveals that
the modulation in the axis for doped 2212 is dominantly
of type that is not sensitive to the oxygen content of the system, and the
system clearly shows a structure of orthorhombic symmetry. Oxygen annealed
samples exhibit a much lower axis resistivity and a resistivity minimum at
K. He-annealed samples exhibit a much higher axis resistivity and
behavior below 300K. The Fermi surface (FS) of oxygen annealed
2212 mapped out by ARUPS has a pocket in the FS around the
point and exhibits orthorhombic symmetry. There are flat, parallel sections of
the FS, about 60\% of the maximum possible along , and about 30\%
along . The wavevectors connecting the flat sections are about
along , and about along , rather than . The symmetry of the near-Fermi-energy dispersing
states in the normal state changes between oxygen-annealed and He-annealed
samples.Comment: APS_REVTEX 3.0, 49 pages, including 11 figures, available upon
request. Submitted to Phys. Rev. B
Transcriptional Analysis of Distant Signaling Induced by Insect Elicitors and Mechanical Wounding in Zea mays
When plants are under insect herbivore attack defensive measures are activated not only locally, but also in distant and systemic tissues. While insect elicitors (IE) abundant in the oral secretions of the attacking herbivore are essential in the regulation of induced defenses, little is known about their effects on systemic defense signaling in maize (Zea mays). The goal of this study was therefore to identify genetic markers that can be used to further characterize local and systemic signaling events induced by IE or mechanical wounding (MW). We selected genes for this study based on their putative involvement in signaling (allene oxide synthase), regulation of gene expression (transcription factor MYC7), and in direct defenses (ribosome inactivating protein) and analyzed their expression in different sections of the treated leaf as well as in systemic parts of the same plant. We found the most significant transcript accumulation of the selected genes after treatment with insect elicitors in those parts with increased JA levels. Additionally, treatment with IE did also induce the accumulation of MYC7 transcripts in basal parts of the treated leaf and systemically. MW, in contrast, did induce RIP and AOS only locally, but not MYC7. This local suppression of MYC7 was further studied by adding glutathione (GSH) as an electron donor to MW plants to quench putative α, β-unsaturated carbonyls, which build up to significant levels around the damage site. Indeed, GSH-treated MW plants accumulated MYC7 at the damage site and also produced more volatiles, suggesting a putative redox-regulatory element being involved in the suppression of MYC7. The results presented herein provide evidence for the specific induction of distant signaling events triggered by IE, most likely through electric signaling. Additionally, a putative role for MW-induced α, β-unsaturated carbonyls in the transcriptional regulation of defense genes was discovered
Hypersensitive Response-Like Reaction Is Associated with Hybrid Necrosis in Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii Coss
BACKGROUND: Hybrid speciation is classified into homoploid and polyploid based on ploidy level. Common wheat is an allohexaploid species that originated from a naturally occurring interploidy cross between tetraploid wheat and diploid wild wheat Aegilops tauschii Coss. Aegilops tauschii provides wide naturally occurring genetic variation. Sometimes its triploid hybrids with tetraploid wheat show the following four types of hybrid growth abnormalities: types II and III hybrid necrosis, hybrid chlorosis, and severe growth abortion. The growth abnormalities in the triploid hybrids could act as postzygotic hybridization barriers to prevent formation of hexaploid wheat. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report on the geographical and phylogenetic distribution of Ae. tauschii accessions inducing the hybrid growth abnormalities and showed that they are widely distributed across growth habitats in Ae. tauschii. Molecular and cytological characterization of the type III necrosis phenotype was performed. The hybrid abnormality causing accessions were widely distributed across growth habitats in Ae. tauschii. Transcriptome analysis showed that a number of defense-related genes such as pathogenesis-related genes were highly up-regulated in the type III necrosis lines. Transmission electron microscope observation revealed that cell death occurred accompanied by generation of reactive oxygen species in leaves undergoing type III necrosis. The reduction of photosynthetic activity occurred prior to the appearance of necrotic symptoms on the leaves exhibiting hybrid necrosis. CONCLUSIONS/SIGNIFICANCE: Taking these results together strongly suggests that an autoimmune response might be triggered by intergenomic incompatibility between the tetraploid wheat and Ae. tauschii genomes in type III necrosis, and that genetically programmed cell death could be regarded as a hypersensitive response-like cell death similar to that observed in Arabidopsis intraspecific and Nicotiana interspecific hybrids. Only Ae. tauschii accessions without such inhibiting factors could be candidates for the D-genome donor for the present hexaploid wheat
Global response of Plasmodium falciparum to hyperoxia: a combined transcriptomic and proteomic approach
<p>Abstract</p> <p>Background</p> <p>Over its life cycle, the <it>Plasmodium falciparum </it>parasite is exposed to different environmental conditions, particularly to variations in O<sub>2 </sub>pressure. For example, the parasite circulates in human venous blood at 5% O<sub>2 </sub>pressure and in arterial blood, particularly in the lungs, at 13% O<sub>2 </sub>pressure. Moreover, the parasite is exposed to 21% O<sub>2 </sub>levels in the salivary glands of mosquitoes.</p> <p>Methods</p> <p>To study the metabolic adaptation of <it>P. falciparum </it>to different oxygen pressures during the intraerythrocytic cycle, a combined approach using transcriptomic and proteomic techniques was undertaken.</p> <p>Results</p> <p>Even though hyperoxia lengthens the parasitic cycle, significant transcriptional changes were detected in hyperoxic conditions in the late-ring stage. Using PS 6.0™ software (Ariadne Genomics) for microarray analysis, this study demonstrate up-expression of genes involved in antioxidant systems and down-expression of genes involved in the digestive vacuole metabolism and the glycolysis in favour of mitochondrial respiration. Proteomic analysis revealed increased levels of heat shock proteins, and decreased levels of glycolytic enzymes. Some of this regulation reflected post-transcriptional modifications during the hyperoxia response.</p> <p>Conclusions</p> <p>These results seem to indicate that hyperoxia activates antioxidant defence systems in parasites to preserve the integrity of its cellular structures. Moreover, environmental constraints seem to induce an energetic metabolism adaptation of <it>P. falciparum</it>. This study provides a better understanding of the adaptive capabilities of <it>P. falciparum </it>to environmental changes and may lead to the development of novel therapeutic targets.</p
Efeitos agudos de diferentes intensidades de exercício sobre a ingestão alimentar pós-exercício
O objetivo do presente estudo foi verificar os efeitos agudos de diferentes intensidades de exercício aerróbio (40 e 80% do VO2pico) sobre a ingestão alimentar pós-exercício. Participaram do estudo 18 adultos jovens, eutróficos (22,20 ± 1,72 kg/m²) e fisicamente ativos. Todos os sujeitos foram submetidos aleatoriamente a três condições experimentais: controle (sem exercício); EBI, exercício de baixa intensidade (40% doVO2pico) e EAI, exercício de alta intensidade (80% do VO2pico). As sessões de exercício foram isocalróricas (350 kcal). Após 120 minutos de recuperação passiva, os voluntários tinham livre acesso a um "buffet" variado de alimentos, a ingestão alimentar foi determinada atravéz da pesagem dos alimentos ingeridos. Os dados alimentares obtidos foram então tabulados e analisados por meio do "software" Nutwin 6.0 (UNIFESP, 2002), para estimativa do consumo energético total (kcal) e ingestão dos macronutrientes (carboidratos, proteínas e lipídeos) em gramas. Os resultados não demonstram nenhuma diferença na ingesto alimentar entre as condições experimentais analisadas. Dessa forma, podemos concluir que a ingestão alimentar pós-exercício não se mostrou dependente da intensidade do esforóo em curto prazo em indivíduos adultos jovens fisicamente ativos.The aim of this study was to investigate the acute effects of different aerobic exercise intensities (40 and 80% do VO2peak) on post-exercise food intake. The sample was composed of eighteen healthy, physically active young men, of normal weight (22.20 ± 1.72 kg/m²). Subjects were randomly submitted to three experimental conditions: control (no exercise); low-intensity exercise (LIE -40% of VO2peak) and high-intensity exercise (HIE- 80% of VO2peak). Exercise trials were iso-caloric (350 Kcal). After 120 minutes of passive recovery, the volunteers had free access to a variety food buffet, and food intake was determined thru food weight. Data was analyzed by the software Nutwin 6.0 (UNIFESP, 2002) to estimate total energy intake (kcal) and consumption of the macronutrients (carbohydrates, proteins and lipids). The results suggest that food intake after exercise showed no significant differences between the experimental conditions. In conclusion, food intake after exercise is not dependent on exercise intensity in healthy young men