The balance between fumarate and malate plays an important role in plant development and postharvest quality in tomato fruit

Organic acids, produced as intermediates of the tricarboxylic cycle, play a crucial role in the plant primary metabolism and are considered as being ones of the most important quality traits in edible fruits. Even if they are key metabolites in a multitude of cellular functions, little is known about their physiological relevance and regulation. Transgenic tomato (Solanum lycopersicum) plants expressing constitutively a bacterial maleate isomerase, which converts reversibly maleate to fumarate, were generated in order to improve our knowledge about the role of organic acids in the crop and fruit metabolism. Growth and reproduction were affected by the unbalance of tricarboxylic cycle intermediates, as a dwarf phenotype and a flowering delay were observed in the transgenic plants. In addition, a delay in chlorophyll synthesis, a decrease in the numbers of stomata and significant changes in some photosynthetic parameters indicated alterations in central primary metabolism. Postharvest was also impaired, as transgenic fruits showed increased water lost and deterioration, indicating a possible role of the organic acids in cell wall metabolism. Finally, preliminary metabolomics analysis pointed out important changes during fruit ripening in flavor-related metabolites, such as acids and sugars, revealing the importance of organic acids in fruit metabolism. Taken together, these data indicate a pivotal role of tricarboxylic cycle intermediates, such as malate or fumarate, as regulatory metabolites. Besides their role in quality fruit characteristics, they are involved in a multitude of functions including growth and photosynthesis.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Rapid in vivo PGC-1 mRNA upregulation in brown adipose tissue of Wistar rats by a beta(3)-adrenergic agonist and lack of effect of leptin.

Peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1) is highly expressed in brown adipose tissue (BAT) and plays an important role in adaptive thermogenesis. The aim of this study was to assess the acute effect of a β3-adrenergic agonist (Trecadrine) and leptin on the expression of PGC-1 and PPARγ2 mRNA in BAT. Trecadrine produced a marked increase (4.5-fold) in PGC-1 mRNA compared to controls (P<0.001) without changes in PPARγ2 mRNA, whereas leptin administration did not alter either PGC-1 or PPARγ2 expression. These results show that selective stimulation of the β3-adrenoceptor rapidly upregulates the expression of PGC-1 in brown adipocytes without a concomitant increase in PPARγ2. Moreover, our results show that PGC-1 and PPARγ2 expression in BAT seems not to be acutely regulated by leptin

A combined algorithm approach for PD location estimation using RF antennas

To locate the positions of partial discharge sources in free space at least four RF antennas are arranged in a suitable spatial geometry to detect the radiated electromagnet energy from the discharge. The time-difference-of-arrival (TDOA) between the signals from each antenna are then used within multi-lateration equations to determine the position of the source. The iterative Hyperbolic Least Squares (HLS) method and the non-iterative Maximum Likelihood Estimator (MLE) method are two common techniques used in the literature to solve the multi-lateration equations. This paper investigates the ability of combining MLE and HLS to improve location accuracy and maintain fast location computation time. To this end HLS, MLE and the combined MLEHLS method are evaluated in terms of location accuracy and computation performance for three spatial antenna configurations, namely Square, Pyramidal and Trapezoidal arrangements. The location accuracies for each method are evaluated for theoretical TDOA values and also for the case when a finite sampling rate of 10G samples-per-second is considered, the latter is implemented through appropriate rounding up of TDOA values by one sample time. It is shown that MLE-HLS produces improved location accuracy compared with HLS and MLE for both theoretical and finite sampled TDOA values. In addition, it is shown that MLE-HLS improves significantly the computation time over the iterative HLS method

A combined algorithm approach for PD location estimation using RF antennas

To locate the positions of partial discharge sources in free space at least four RF antennas are arranged in a suitable spatial geometry to detect the radiated electromagnet energy from the discharge. The time-difference-of-arrival (TDOA) between the signals from each antenna are then used within multi-lateration equations to determine the position of the source. The iterative Hyperbolic Least Squares (HLS) method and the non-iterative Maximum Likelihood Estimator (MLE) method are two common techniques used in the literature to solve the multi-lateration equations. This paper investigates the ability of combining MLE and HLS to improve location accuracy and maintain fast location computation time. To this end HLS, MLE and the combined MLEHLS method are evaluated in terms of location accuracy and computation performance for three spatial antenna configurations, namely Square, Pyramidal and Trapezoidal arrangements. The location accuracies for each method are evaluated for theoretical TDOA values and also for the case when a finite sampling rate of 10G samples-per-second is considered, the latter is implemented through appropriate rounding up of TDOA values by one sample time. It is shown that MLE-HLS produces improved location accuracy compared with HLS and MLE for both theoretical and finite sampled TDOA values. In addition, it is shown that MLE-HLS improves significantly the computation time over the iterative HLS method

Prolonged food deprivation increases mRNA expression of deiodinase 1 and 2, and thyroid hormone receptor β-1 in a fasting-adapted mammal

Food deprivation in mammals is typically associated with reduced thyroid hormone (TH) concentrations and deiodinase content and activity to suppress metabolism. However, in prolonged-fasted, metabolically active elephant seal pups, TH levels are maintained, if not elevated. The functional relevance of this apparent paradox is unknown and demonstrates variability in the regulation of TH levels, metabolism and function in food-deprived mammals. To address our hypothesis that cellular TH-mediated activity is upregulated with fasting duration, we quantified the mRNA expression and protein content of adipose and muscle deiodinase type I (DI1) and type II (DI2), and TH receptor beta-1 (THrβ-1) after 1, 3 and 7 weeks of fasting in northern elephant seal pups (N=5–7 per week). Fasting did not decrease the concentrations of plasma thyroid stimulating hormone, total triiodothyronine (tT(3)), free T(3), total thyroxine (tT(4)) or free T(4), suggesting that the hypothalamic–pituitary–thyroid axis is not suppressed, but rather maintained during fasting. Mean mRNA expression of adipose DI1 and DI2 increased threefold and fourfold, respectively, and 20- and 30-fold, respectively, in muscle. With the exception of adipose DI1, protein expression of adipose DI2 and muscle DI1 and DI2 increased twofold to fourfold. Fasting also increased adipose (fivefold) and muscle (fourfold) THrβ-1 mRNA expression, suggesting that the mechanisms mediating cellular TH activity are upregulated with prolonged fasting. The data demonstrate a unique, atypical mechanism of TH activity and regulation in mammals adapted to prolonged food deprivation in which the potential responsiveness of peripheral tissues and cellular TH activity are increased, which may contribute to their lipid-based metabolism

Genetic differentiation between natural populations of Drosophila subobscura in the Western Mediterranean Area with respect to chromosomal variation

International audienc

Statin pretreatment diminishes the levels of myocardial ischemia markers not only in CABG

A response to Ege E, Dereli Y, Kurban S, Sarigul A: Atorvastatin pretreatment diminishes the levels of myocardial ischemia markers early after CABG operation: an observational study. J Cardiothorac Surg 2010, 5:60

Dietary total antioxidant capacity is associated with leukocyte telomere length in a children and adolescent population

Background & Aims: Oxidative stress and inflammation seem to be potential underlying mechanisms for telomere attrition. A lack of specific antioxidants is believed to increase free radical damage and a greater risk for telomere shortening. Our aim was to evaluate the relationship between diet and leukocyte telomere length in a cross-sectional study of children and adolescents. We hypothesized that dietary total antioxidant capacity would be positively associated with telomere length. Methods: Telomere length was measured by quantitative real-time polymerase chain reaction in 287 participants (55% males, 6–18 years), who were randomly selected from the GENOI study. Results: A positive correlation between dietary total antioxidant capacity and telomere length (r=0.157, p=0.007) was found after adjustment for age and energy intake. However, higher white bread consumption was associated with shorter telomeres (β=-0.204, p=0.002) in fully-adjusted models. Interestingly, those individuals who had simultaneously higher dietary total antioxidant capacity and lower white bread consumption significantly presented the longest telomeres. Moreover, the multivariable-adjusted odds ratio for very short telomeres was 0.30 for dietary total antioxidant capacity (p=0.023) and 1.37 for white bread (p=0.025). Conclusion: It was concluded that longer telomeres were associated with higher dietary total antioxidant capacity and lower white bread consumption in S2panish children and adolescents. These findings might open a new line of investigation about the potential role of an antioxidant diet in maintaining telomere length

CARACTERIZACIÓN DE LAS PROPIEDADES NUTRICIONALES Y ANTIOXIDANTES DE SEMILLAS DE QUINUA (Chenopodium quinoa WILLD.)

[EN] Interest in the cultivation of quinoa pseudo-cereal (Chenopodium quinoa Willd.) has increased in recent years due to its nutritional value, as well as its antioxidant capacity and phytochemical content. The chemical composition of quinoa seeds and their bioactive compounds can differ between varieties. In this study, the nutritional composition, antioxidant properties and total phenolic content of Yellow quinoa seeds cultivated in Mexico were evaluated. The results were compared with four commercial quinoa varieties from Peru: Yellow, Black, Red and Peruvian Yellow. The chemical composition of seeds in this study varied as a function of germplasm and growing conditions. In general, samples were characterized by their high carbohydrate content, followed by protein, lipids and fiber. The Yellow quinoa grown in Mexico stood out for its high phenolic content, as well as for its antioxidant activity, probably influenced by the presence of saponins.Carranza-Concha, J.; Chairez-Huerta, SG.; Contreras-Martinez, CS.; García Martínez, EM. (2021). Characterization of nutritional and antioxidant properties of Quinoa seeds (Chenopodium quinoa WILLD.). Revista Fitotecnia Mexicana. 44(3):357-366. http://hdl.handle.net/10251/18680435736644