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Background: Poor diet quality contributes to morbidity and mortality and affects environmental sustainability. The EAT-Lancet reference diet offers a healthy and sustainable solution. This study aimed to estimate the association between diet cost and dietary quality, measured with an EAT-Lancet Index., Methods: An EAT-Lancet index was adapted to assess adherence to this dietary pattern from 24-h recalls data from the 2012 and 2016 Mexican National Health and Nutrition Surveys (n = 14,242). Prices were obtained from the Consumer Price Index. We dichotomized cost at the median (into low- and high-cost) and compared the EAT-Lancet index scores. We also used multivariate linear regression models to explore the association between diet cost and diet quality., Results: Individuals consuming a low-cost diet had a higher EAT-Lancet score than those consuming a high-cost diet (20.3 vs. 19.4 from a possible scale of 0 to 42; p < 0.001) due to a lower intake of beef and lamb, pork, poultry, dairy, and added sugars. We found that for each one-point increase in the EAT-Lancet score, there was an average decrease of MXN$0.4 in the diet cost (p < 0.001). This association was only significant among low- and middle-SES individuals., Conclusions: Contrary to evidence from high-income countries, this study shows that in Mexico, adhering to the EAT-Lancet reference diet is associated with lower dietar costs, particularly in lower SES groups. These findings suggest the potential for broader implementation of healthier diets without increasing the financial burden., (© 2024. The Author(s).)

Background: Since 2020 in Mexico, front-of-pack warning labels (FOPWL) have been implemented in processed products. Evidence supports warning labels allow consumers to identify unhealthy products. We aimed to evaluate the hypothetical impact of the FOPWL regulation on the Mexican population's intake of critical nutrients and energy, based on the replacement of food and beverages using 4 hypothetical scenarios which represented the phases of the regulation., Methods: Dietary data were collected using a standardized 24-h dietary recall from the 2016 Mexican National Health and Nutrition Survey (n = 4184). To evaluate the hypothetical impact of FOPWL, the nutritional content of critical nutrients in processed products was evaluated according to the Mexican Official Standard 051 (NOM-051). Then, we replaced products with several warning labels (WL) with those with a fewer number of them or with non-processed food. For the replacement, 4 hypothetical scenarios were established: scenario 1: the current consumption of the Mexican Population, scenario 2: the replacement during the first phase of the norm, scenario 3: the replacement in the second phase and scenario 4: the replacement in the last phase. We estimated the means, confidence intervals (CI 95%), and the mean percentage change of energy, saturated fat, trans-fat, added sugars, and sodium intake during the second, third, and the fourth scenarios., Results: According to the norm, in the second scenario, the majority of the products presented a label for energy (52.6%) whereas in the third (56.4%) and fourth (61.2%) scenarios were for sodium. In contrast, trans-fat was the least labeled nutrient in all the scenarios (from 2.1 to 4.1%). In the fourth scenario, we observed a reduction of the intake of energy intake to 15.4% as well as saturated fat (- 20%, CI 95% - 18.4; - 21.6), trans-fat (- 8.2%, CI 95% - 6.4; - 10.1) and sodium (- 12.7%, CI 95% - 11.3; - 14.1). The most important reduction was observed for added sugars intake (until - 54.1%, CI 95% - 51; - 57.1)., Conclusions: FOPWL could be an effective strategy to decrease energy consumption and nutrients of concern. If consumers use the FOPWL, it would be an important change in critical nutrients intake. These results support that FOPWL might help the Mexican population to choose healthier nutrition alternatives., (© 2023. The Author(s).)

Background: Iron is essential for the maintenance of basic cellular processes. In the regulation of its cellular levels, ferritin acts as the main intracellular iron storage protein. In this work we present a mathematical model for the dynamics of iron storage in ferritin during the process of intestinal iron absorption. A set of differential equations were established considering kinetic expressions for the main reactions and mass balances for ferritin, iron and a discrete population of ferritin species defined by their respective iron content., Results: Simulation results showing the evolution of ferritin iron content following a pulse of iron were compared with experimental data for ferritin iron distribution obtained with purified ferritin incubated in vitro with different iron levels. Distinctive features observed experimentally were successfully captured by the model, namely the distribution pattern of iron into ferritin protein nanocages with different iron content and the role of ferritin as a controller of the cytosolic labile iron pool (cLIP). Ferritin stabilizes the cLIP for a wide range of total intracellular iron concentrations, but the model predicts an exponential increment of the cLIP at an iron content > 2,500 Fe/ferritin protein cage, when the storage capacity of ferritin is exceeded., Conclusions: The results presented support the role of ferritin as an iron buffer in a cellular system. Moreover, the model predicts desirable characteristics for a buffer protein such as effective removal of excess iron, which keeps intracellular cLIP levels approximately constant even when large perturbations are introduced, and a freely available source of iron under iron starvation. In addition, the simulated dynamics of the iron removal process are extremely fast, with ferritin acting as a first defense against dangerous iron fluctuations and providing the time required by the cell to activate slower transcriptional regulation mechanisms and adapt to iron stress conditions. In summary, the model captures the complexity of the iron-ferritin equilibrium, and can be used for further theoretical exploration of the role of ferritin in the regulation of intracellular labile iron levels and, in particular, as a relevant regulator of transepithelial iron transport during the process of intestinal iron absorption.

Background: To allow the survival of the population in the absence of nitrogen, some cyanobacteria strains have developed the capability of differentiating into nitrogen fixing cells, forming a characteristic pattern. In this paper, the process by which cyanobacteria differentiates from vegetative cells into heterocysts in the absence of nitrogen and the elements of the gene network involved that allow the formation of such a pattern are investigated., Methods: A simple gene network model, which represents the complexity of the differentiation process, and the role of all variables involved in this cellular process is proposed. Specific characteristics and details of the system's behavior such as transcript profiles for ntcA, hetR and patS between consecutive heterocysts were studied., Results: The proposed model is able to capture one of the most distinctive features of this system: a characteristic distance of 10 cells between two heterocysts, with a small standard deviation according to experimental variability. The system's response to knock-out and over-expression of patS and hetR was simulated in order to validate the proposed model against experimental observations. In all cases, simulations show good agreement with reported experimental results., Conclusion: A simple evolution mathematical model based on the gene network involved in heterocyst differentiation was proposed. The behavior of the biological system naturally emerges from the network and the model is able to capture the spacing pattern observed in heterocyst differentiation, as well as the effect of external perturbations such as nitrogen deprivation, gene knock-out and over-expression without specific parameter fitting.