Ferritin levels and COVID-19 Vargas-Vargas, Manuel; Cortés-Rojo, Christian
Revista panamericana de salud pública,
01/2020, Letnik:
44, Številka:
72
Journal Article
Metabolic diseases are characterized by high NADH/NAD+ ratios due to excessive electron supply, causing defective mitochondrial function and impaired sirtuin-3 (SIRT-3) activity, the latter driving ...to oxidative stress and altered fatty acid β-oxidation. NADH is oxidized by the complex I in the electron transport chain, thereby factors inhibiting complex I like acetylation, cardiolipin peroxidation, and glutathionylation by low GSH/GSSG ratios affects SIRT3 function by increasing the NADH/NAD+ ratio. In this review, we summarized the evidence supporting a role of the above events in the development of insulin resistance, which is relevant in the pathogenesis of obesity and diabetes. We propose that maintenance of proper NADH/NAD+ and GSH/GSSG ratios are central to ameliorate insulin resistance, as alterations in these redox couples lead to complex I dysfunction, disruption of SIRT-3 activity, ROS production and impaired β-oxidation, the latter two being key effectors of insulin resistance.
•Diabetes, obesity, and insulin resistance involve alterations in NADH and GSH levels.•High NADH/NAD+ ratios and low GSH/GSSG ratios impairs mitochondrial metabolism.•Incomplete fatty acid β-oxidation in mitochondria may lead to insulin resistance.•Cardiolipin peroxidation impairs NADH oxidation by the complex I in mitochondria.•NAD+, GSH and cardiolipin levels may be targets for insulin resistance treatment.
Background: The alarming increase in childhood obesity is a global public health problem since it has significant health consequences. This cross-sectional study aimed to identify the potentially ...modifiable risk factors for developing excess weight and determine the importance of developing certain habits to prevent childhood overweight and obesity. Methods: The sample included 416 students between the ages of 12 and 14 (12.8 ± 0.62) first-year high school students from Murcia in Spain. Data were collected on their lifestyle habits through the ENHASA questionnaire, and the somatometry of the participants was measured. Such data were studied through structural equation modeling and importance-performance map analyses. Results: The modifiable risk factors that presented the greatest potency directly regarding when developing excess weight in adolescents were ‘use of electronic devices’ and ‘not performing physical activity’ (p < 0.001). ‘Social and school environment’ and ‘diet’ showed relationships but no significant differences with overweight or obesity. Globally, the lifestyle habit of the greatest importance for not being overweight was ‘engagement in extracurricular physical activities’. On the other hand, the habits related to using new technologies in a sedentary way showed the best capacity for improvement. Therefore, it would be very efficient to focus on them to control excess weight. Conclusion: Responsible and limited use of screens and engaging in extracurricular physical activities may be the most remarkable and cost-effective strategies for obesity prevention programs.
High fat or fructose induces non-alcoholic fatty liver disease (NAFLD) accompanied of mitochondrial dysfunction and oxidative stress. Controversy remains about whether fructose or fat is more ...deleterious for NAFLD development. To get more insights about this issue and to determine if the severity of liver disease induced by fructose or fat is related to degree of mitochondrial dysfunction, we compared the effects of diets containing high fat (HF), fructose (Fr) or high fat plus fructose (HF + Fr) on NAFLD development, mitochondrial function, ROS production and lipid peroxidation.
Wistar rats were assigned to four groups: Control, fed with standard rodent chow; High fat (HF), supplemented with lard and hydrogenated vegetable oil; Fructose (Fr), supplemented with 25% fructose in the drinking water; High fat plus fructose group (HF + Fr), fed with both HF and Fr diets. Rats were sacrificed after 6 weeks of diets consumption and the liver was excised for histopathological analysis by hematoxylin and eosin staining and for mitochondria isolation. Mitochondrial function was evaluated by measuring both mitochondrial respiration and complex I activity. Lipid peroxidation and ROS production were evaluated in mitochondria by the thiobarbituric acid method and with the fluorescent ROS probe 2,4-H
DCFDA, respectively.
Fr group underwent the lower degree of both liver damage and mitochondrial dysfunction that manifested like less than 20% of hepatocytes with microvesicular steatosis and partial decrease in state 3 respiration, respectively. HF group displayed an intermediate degree of damage as it showed 40% of hepatocytes with microvesicular steatosis and diminution of both state 3 respiration and complex I activity. HF + Fr group displayed more severe damage as showed microvesicular steatosis in 60% of hepatocytes and inflammation, while mitochondria exhibited fully inhibited state 3 respiration, impaired complex I activity and increased ROS generation. Exacerbation of mitochondrial lipid peroxidation was observed in both the Fr and HF + Fr groups.
Severity of liver injury induced by fructose or fat was related to the degree of dysfunction and oxidative damage in mitochondria. Attention should be paid on the serious effects observed in the HF + Fr group as the typical Western diet is rich in both fat and carbohydrates.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Mean cell size at division is generally constant for specific conditions and cell types, but the mechanisms coupling cell growth and cell cycle control with cell size regulation are poorly understood ...in intact tissues. Here we show that the continuously dividing fields of cells within the shoot apical meristem of Arabidopsis show dynamic regulation of mean cell size dependent on developmental stage, genotype and environmental signals. We show cell size at division and cell cycle length is effectively predicted using a two-stage cell cycle model linking cell growth and two sequential cyclin dependent kinase (CDK) activities, and experimental results concur in showing that progression through both G1/S and G2/M is size dependent. This work shows that cell-autonomous co-ordination of cell growth and cell division previously observed in unicellular organisms also exists in intact plant tissues, and that cell size may be an emergent rather than directly determined property of cells.
•Unimodal regularisation for cross-entropy loss using the beta distribution.•Comparison with other regularisation methods based on other distributions.•Ordinal output scheme based on the ...stick-breaking process.•Application to convolutional neural networks and several benchmark datasets.
Currently, the use of deep learning for solving ordinal classification problems, where categories follow a natural order, has not received much attention. In this paper, we propose an unimodal regularisation based on the beta distribution applied to the cross-entropy loss. This regularisation encourages the distribution of the labels to be a soft unimodal distribution, more appropriate for ordinal problems. Given that the beta distribution has two parameters that must be adjusted, a method to automatically determine them is proposed. The regularised loss function is used to train a deep neural network model with an ordinal scheme in the output layer. The results obtained are statistically analysed and show that the combination of these methods increases the performance in ordinal problems. Moreover, the proposed beta distribution performs better than other distributions proposed in previous works, achieving also a reduced computational cost.
This essay considers various kinds of manipulation cases (local and global, dispositional and situational), and how Doris's Deep Self-style theory of responsibility fares in light of them. Agents ...acting with preferences adaptively formed under oppression are an especially interesting challenge for this sort of view, and the article considers what options may be available to Doris and others.
The performance of vehicle safety systems depends very much on the accuracy of the signals coming from vehicle sensors. Among them, the wheel speed is of vital importance. This paper describes a new ...method to obtain the wheel speed by using Sin-Cos encoders. The methodology is based on the use of the Savitzky-Golay filters to optimally determine the coefficients of the polynomials that best fit the measured signals and their time derivatives. The whole process requires a low computational cost, which makes it suitable for real-time applications. This way it is possible to provide the safety system with an accurate measurement of both the angular speed and acceleration of the wheels. The proposed method has been compared to other conventional approaches. The results obtained in simulations and real tests show the superior performance of the proposed method, particularly for medium and low wheel angular speeds.
ROS-induced DNA damage and PARP-1 are required for optimal induction of starvation-induced autophagy Jose Manuel Rodriguez-Vargas Maria Jose Ruiz-Magana Carmen Ruiz-Ruiz Jara Majuelos-Melguizo Andreina Peralta-Lea Maria Isabel Rodriguez Jose Antonio Munoz-Gaimez Mariano Ruiz de Almodovar Eva Siles Abelardo Lopez Rivas Marja Jaattela F Javier Oliver
Cell research,
07/2012, Letnik:
22, Številka:
7
Journal Article
Recenzirano
Odprti dostop
In response to nutrient stress, cells start an autophagy program that can lead to adaptation or death. The mechanisms underlying the signaling from starvation to the initiation of autophagy are not ...fully understood. In the current study we show that the absence or inactivation of PARP-1 strongly delays starvation-induced autophagy. We have found that DNA damage is an early event of starvation-induced autophagy as measured by y-H2AX accumulation and comet assay, with PARP-1 knockout cells displaying a reduction in both parameters. During starvation, ROS- induced DNA damage activates PARP-1, leading to ATP depletion （an early event after nutrient deprivation）. The absence of PARP-1 blunted AMPK activation and prevented the complete loss of mTOR activity, leading to a delay in autophagy. PARP-1 depletion favors apoptosis in starved cells, suggesting a pro-survival role of autophagy and PARP-1 activation after nutrient deprivation. In vivo results show that neonates of PARP-1 mutant mice subjected to acute starvation, also display deficient liver autophagy, implying a physiological role for PARP-1 in starvation-in- duced autophagy. Thus, the PARP signaling pathway is a key regulator of the initial steps of autophagy commitment following starvation.
•Calcination conditions of Ni/YSZ modified the number of surface oxygen vacancies.•Ni/Al2O3 catalyst has poor activity due to the formation of NiAl2O4 metal phase.•The H2/CO molar ratio obtained in ...tri-reforming is affected by the support basicity.•CeO2 and β-SiC supported catalysts showed the best catalytic performance.
The influence of different support materials (alumina, ceria, β-silicon carbide and yttria-stabilized zirconia) on the catalytic behaviour of Ni catalysts for the dry reforming reaction and the tri-reforming process has been studied. The influence on the catalytic performance of the composition of the atmosphere surrounding the Ni/YSZ catalyst during the calcination step was also analysed. Temperature-programmed reduction experiments showed remarkable differences in the reduction profile and the degree of reduction of the catalysts as a function of both the support used and the calcination conditions. Ni/YSZ-O2, the catalyst calcined under an oxygen-poor atmosphere, presented a higher reducibility as a consequence of the higher number of oxygen vacancies in the surface of the support. The Ni/Al2O3 catalyst gave the lowest CH4 and CO2 reaction rates as a consequence of its low reducibility due to the formation of Ni aluminate. The Ni/CeO2 catalyst showed the lowest H2/CO molar ratio for the tri-reforming process. This result can be explained on considering the higher basicity of this catalyst, as shown by CO2-TPD experiments. The CeO2 and β-SiC catalysts had the best characteristics as catalytic supports for the tri-reforming process.
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