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We identified the main changes in serum metabolites associated with severe (n = 46) and mild (n = 19) COVID-19 patients by gas chromatography coupled to mass spectrometry. The modified metabolic profiles were associated to an altered amino acid catabolism in hypoxic conditions. Noteworthy, three α-hydroxyl acids of amino acid origin increased with disease severity and correlated with altered oxygen saturation levels and clinical markers of lung damage. We hypothesize that the enzymatic conversion of α-keto-acids to α- hydroxyl-acids helps to maintain NAD recycling in patients with altered oxygen levels, highlighting the potential relevance of amino acid supplementation during SARS-CoV-2 infection.

Antimicrobial peptides (AMPs) are part of the innate immune defense mechanism of many organisms and are promising candidates to treat infections caused by pathogenic bacteria to animals and humans. AMPs also display anticancer activities because of their ability to inactivate a wide range of cancer cells. Cancer remains a cause of high morbidity and mortality worldwide. Therefore, the development of methods for its control is desirable. Attractive alternatives include plant AMP thionins, defensins, and cyclotides, which have anticancer activities. Here, we provide an overview of plant AMPs anticancer activities, with an emphasis on their mode of action, their selectivity, and their efficacy.

SARS-CoV-2 infection represents a global health problem that has affected millions of people. The fine host immune response and its association with the disease course have not yet been fully elucidated. Consequently, we analyze circulating B cell subsets and their possible relationship with COVID-19 features and severity. Using a multiparametric flow cytometric approach, we determined B cell subsets frequencies from 52 COVID-19 patients, grouped them by hierarchical cluster analysis, and correlated their values with clinical data. The frequency of CD19 B cells is increased in severe COVID-19 compared to mild cases. Specific subset frequencies such as transitional B cell subsets increase in mild/moderate cases but decrease with the severity of the disease. Memory B compartment decreased in severe and critical cases, and antibody-secreting cells are increased according to the severity of the disease. Other non-typical subsets such as double-negative B cells also showed significant changes according to disease severity. Globally, these differences allow us to identify severity-associated patient clusters with specific altered subsets. Finally, respiratory parameters, biomarkers of inflammation, and clinical scores exhibited correlations with some of these subpopulations. The severity of COVID-19 is accompanied by changes in the B cell subpopulations, either immature or terminally differentiated. Furthermore, the existing relationship of B cell subset frequencies with clinical and laboratory parameters suggest that these lymphocytes could serve as potential biomarkers and even active participants in the adaptive antiviral response mounted against SARS-CoV-2.

Confinement due to the COVID-19 pandemic can influence dietary profiles, especially those of adolescents, who are highly susceptible to acquiring bad eating habits. Adolescents’ poor dietary habits increase their subsequent risk of degenerative diseases such as obesity, diabetes, cardiovascular pathologies, etc. Our aim was to study nutritional modifications during COVID-19 confinement in adolescents aged 10 to 19 years, compare them with their usual diet and dietary guidelines, and identify variables that may have influenced changes. Data were collected by an anonymous online questionnaire on food intake among 820 adolescents from Spain, Italy, Brazil, Colombia, and Chile. The results show that COVID-19 confinement did influence their dietary habits. In particular, we recorded modified consumption of fried food, sweet food, legumes, vegetables, and fruits. Moreover, gender, family members at home, watching TV during mealtime, country of residence, and maternal education were diversely correlated with adequate nutrition during COVID-19 confinement. Understanding the adolescents’ nutrition behavior during COVID-19 lockdown will help public health authorities reshape future policies on their nutritional recommendations, in preparation for future pandemics.

Aim: to describe physical activity and ultra-processed foods consumption, their changes and sociodemographic predictors among adolescents from countries in Europe (Italy and Spain) and Latin America (Brazil, Chile, and Colombia) during the SARS-CoV-2-pandemic period. Methods: Cross-sectional study via web survey. International Physical Activity Questionnaire (IPAQ) and weekly ultra-processed food consumption data were used. To compare the frequencies of physical activity status with sociodemographic variables, a multinomial logistic and a multiple logistic regression for habitual ultra-processed foods was performed. In final models, p < 0.05 was considered significant. Results: Sample of 726 adolescents, mostly females (59.6%) aged 16–19 years old (54.3%). Adolescents from Latin America presented odds ratio (OR) 2.98 (CI 95% 1.80–4.94) of being inactive and those whose mothers had higher level of education were less active during lockdown [OR 0.40 (CI 95% 0.20–0.84)]. The habitual ultra-processed consumption was also high during this period in all countries, and more prevalent in Latin America. Conclusion: A higher prevalence of inactivity was observed in this population, but reductions of physical activity and habitual ultra-processed consumption during the pandemic were more pronounced in Latin America. Our findings reinforce the importance of promoting a healthy lifestyle, i.e., exercise and diet, during periods of social isolation.

Different ethnomedicinal studies have investigated the relationship between various phytochemicals as well as organic extracts and their bioactive aspects. Studies on biological effects are attributed to secondary metabolites such as alkaloids, phenolic compounds, and terpenes. Since there have been no reviews in the literature on the traditional, phytochemical, and ethnomedicinal uses of the genus Aristolochia so far, this article systematically reviews 141 published studies that analyze the associations between secondary metabolites present in organic extracts and their beneficial effects. Most studies found associations between individual secondary metabolites and beneficial effects such as anticancer activity, antibacterial, antioxidant activity, snake anti-venom and anti-inflammatory activity. The aim of this review was to analyze studies carried out in the period 2005–2021 to update the existing knowledge on different species of the genus Aristolochia for ethnomedicinal uses, as well as pharmacological aspects and therapeutic uses.

Estrogens and their role in cancer are well-studied, and some cancer types are classified in terms of their response to them. In recent years, a G protein-coupled estrogen receptor (GPER) has been described with relevance in cancer. GPER is a pleiotropic receptor with tissue-specific activity; in normal tissues, its activation is related to correct development and homeostasis, while in cancer cells, it can be pro- or anti-tumorigenic. Also, GPER replaces estrogen responsiveness in estrogen receptor alpha (ERα)-lacking cancer cell lines. One of the most outstanding activities of GPER is its role in epithelial–mesenchymal transition (EMT), which is relevant for metastasis development. In addition, the presence of this receptor in tumor microenvironment cells contributes to the phenotypic plasticity required for the dissemination and maintenance of tumors. These characteristics suggest that GPER could be a promising therapeutic target for regulating cancer development. This review focuses on the role of GPER in EMT in tumorigenic and associated cells, highlighting its role in relation to the main hallmarks of cancer and possible therapeutic options.

The objective of this work was to analyse the effect of partial sucrose replacement by isomalt on the thermal, rheological, and moisture sorption behaviour of cocoa-flavoured confectionery coatings. Formulations were elaborated using sucrose, isomalt, cocoa powder, vegetable oil, lecithin, glycerol, and water. Full-sugar sample (0%) was used as control and reduced-sugar formulations were obtained by replacing 25% and 50% of the sucrose by isomalt. Flow behaviour and thixotropy of liquid formulations were evaluated. Thermal properties (by differential scanning calorimetry) and moisture adsorption and desorption isotherms at 25 °C of films (dried by casting at 40 °C and 26% relative humidity for 24 h) were obtained in the water activity range of 0.225–0.927. Rheological behaviour was described by the Cross model and a first-order structural kinetic model. Sorption isotherms were analysed applying the Generalised D’Arcy and Watt (GDW) and Chi models. The presence of isomalt affected the rheology of liquid formulations, especially in the 50% sample. Similar thixotropic behaviour was found between 0% and 25% samples, with a ~ 100% recovery, indicating a better coating performance. The range of the mean onset (36–41 °C) and melting (95–155 °C) temperatures obtained was high, suggesting that the solid structure of films will be preserved at room storage conditions. The sorption isotherms showed a type-III shape, evidencing two characteristic surfaces with different sorption energies, and hysteresis between adsorption and desorption. The GDW and Chi models accurately described the isotherms. These results are useful to control the elaboration and conservation of reduced-sugar confectionery coatings.

Observations of a stellar occultation of Haumea, one of the four known trans-Neptunian dwarf planets, constrain its size, shape and density, and reveal a ring coplanar with Haumea’s largest moon. A ring around Haumea Haumea is a dwarf planet beyond the orbit of Neptune. It is rapidly rotating and very elongated, unlike the other three known trans-Neptunian dwarf planets. Jose Ortiz and collaborators obtained observations from multiple Earth-based telescopes as Haumea passed in front of a background star. This occultation enabled the team to constrain the density of Haumea to an upper limit of about 1,885 kilograms per cubic metre. They also constrained its ellipsoid shape and albedo (0.51). They did not detect an atmosphere around the planet, but found a ring circling it. They determined that the ring is 70 kilometres wide, has a radius of about 2,287 kilometres and lies in the same orbital plane as Haumea's equator and largest moon. It has an orbital period that is three times the spin period of Haumea. The ring absorbed roughly half of the star light coming through, giving it an opacity of 0.5. Haumea—one of the four known trans-Neptunian dwarf planets—is a very elongated and rapidly rotating body 1 , 2 , 3 . In contrast to other dwarf planets 4 , 5 , 6 , its size, shape, albedo and density are not well constrained. The Centaur Chariklo was the first body other than a giant planet known to have a ring system 7 , and the Centaur Chiron was later found to possess something similar to Chariklo’s rings 8 , 9 . Here we report observations from multiple Earth-based observatories of Haumea passing in front of a distant star (a multi-chord stellar occultation). Secondary events observed around the main body of Haumea are consistent with the presence of a ring with an opacity of 0.5, width of 70 kilometres and radius of about 2,287 kilometres. The ring is coplanar with both Haumea’s equator and the orbit of its satellite Hi’iaka. The radius of the ring places it close to the 3:1 mean-motion resonance with Haumea’s spin period—that is, Haumea rotates three times on its axis in the time that a ring particle completes one revolution. The occultation by the main body provides an instantaneous elliptical projected shape with axes of about 1,704 kilometres and 1,138 kilometres. Combined with rotational light curves, the occultation constrains the three-dimensional orientation of Haumea and its triaxial shape, which is inconsistent with a homogeneous body in hydrostatic equilibrium. Haumea’s largest axis is at least 2,322 kilometres, larger than previously thought, implying an upper limit for its density of 1,885 kilograms per cubic metre and a geometric albedo of 0.51, both smaller than previous estimates 1 , 10 , 11 . In addition, this estimate of the density of Haumea is closer to that of Pluto than are previous estimates, in line with expectations. No global nitrogen- or methane-dominated atmosphere was detected.

Cancer is a relevant health problem worldwide. In 2020, leukemias represented the 13th most commonly reported cancer cases worldwide but the 10th most likely to cause deaths. There has been a progressive increase in the efficacy of treatments for leukemias; however, these still generate important side effects, so it is imperative to search for new alternatives. Defensins are a group of antimicrobial peptides with activity against cancer cells. However, the cytotoxic mechanism of these peptides has been described mainly for animal defensins. This study shows that defensin γ-thionin (Capsicum chinense) is cytotoxic to the K562 leukemia cells with an IC50 = 290 μg/mL (50.26 μM) but not for human peripheral blood mononuclear cells. Results showed that γ-thionin did not affect the membrane potential; however, the peptide modified the mitochondrial membrane potential (ΔΨm) and the intracellular calcium release. In addition, γ-thionin induced apoptosis in K562 cells, but the activation of caspases 8 and 9 was not detected. Moreover, the activation of calpains was detected at one hour of treatment, suggesting that γ-thionin activates the caspase-independent apoptosis. Furthermore, the γ-thionin induced epigenetic modifications on histone 3 in K562 cells, increased global acetylation (~2-fold), and specific acetylation marks at lysine 9 (H3K9Ac) (~1.5-fold). In addition, γ-thionin increased the lysine 9 methylation (H3K9me) and dimethylation marks (H3K9me2) (~2-fold), as well as the trimethylation mark (H3K9me3) (~2-fold). To our knowledge, this is the first report of a defensin that triggers caspase-independent apoptosis in cancer cells via calpains and regulating chromatin remodelation, a novel property for a plant defensin.