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Obesity can lead children and adolescents to an increased cardiovascular disease (CVD) risk. A diet supplemented with Plantago psyllium has been shown to be effective in reducing LDL-C and IL-6 in adolescents. However, there are no studies that have explored small-dense LDL (sdLDL) or HDL subclasses. The aim of this study was to evaluate the impact of a fiber dietary intervention on LDL and HDL subclasses in adolescents with obesity. In this parallel, double blind, randomized clinical trial, the participants were assigned to Plantago psyllium or placebo (10g/day for 7 weeks). We randomized 113 participants, and evaluated and analyzed 100 adolescents (50 in each group), 15 to 19 years with a body mass index of 29-34. We measured biochemical markers LDL and HDL subclasses using the Lipoprint system (Quantimetrix) and IL-6 by ELISA. Post-treatment there was a decrease in sdLDL between the groups 2.0 (0-5.0) vs 1 (0-3.0) mg/dl (p = 0.004), IL-6 median 3.32 (1.24-5.96) vs 1.76 (0.54-3.28) pg/ml, p

Functional status is considered the main determinant of healthy aging. Impairment in skeletal muscle and the cardiovascular system, two interrelated systems, results in compromised functional status in aging. Increased oxidative stress and inflammation in older subjects constitute the background for skeletal muscle and cardiovascular system alterations. Aged skeletal muscle mass and strength impairment is related to anabolic resistance, mitochondrial dysfunction, increased oxidative stress and inflammation as well as a reduced antioxidant response and myokine profile. Arterial stiffness and endothelial function stand out as the main cardiovascular alterations related to aging, where increased systemic and vascular oxidative stress and inflammation play a key role. Physical activity and exercise training arise as modifiable determinants of functional outcomes in older persons. Exercise enhances antioxidant response, decreases age-related oxidative stress and pro-inflammatory signals, and promotes the activation of anabolic and mitochondrial biogenesis pathways in skeletal muscle. Additionally, exercise improves endothelial function and arterial stiffness by reducing inflammatory and oxidative damage signaling in vascular tissue together with an increase in antioxidant enzymes and nitric oxide availability, globally promoting functional performance and healthy aging. This review focuses on the role of oxidative stress and inflammation in aged musculoskeletal and vascular systems and how physical activity/exercise influences functional status in the elderly.

Down syndrome (DS) is the most common genetic cause of developmental disabilities. Advanced analysis of brain magnetic resonance imaging (MRI) has been used to find brain abnormalities and their relationship to neurocognitive impairments in children and adolescents with DS. Because genetic factors affect brain development in early fetal life, there is a growing interest in analyzing brains from living fetuses with DS. In this study, we investigated regional sulcal folding depth as well as global cortical gyrification from fetal brain MRIs. Nine fetuses with DS (29.1 ± 4.24 gestational weeks [mean ± standard deviation]) were compared with 17 typically developing [TD] fetuses (28.4 ± 3.44). Fetuses with DS showed lower whole-brain average sulcal depths and gyrification index than TD fetuses. Significant decreases in sulcal depth were found in bilateral Sylvian fissures and right central and parieto-occipital sulci. On the other hand, significantly increased sulcal depth was shown in the left superior temporal sulcus, which is related to atypical hemispheric asymmetry of cortical folding. Moreover, these group differences increased as gestation progressed. This study demonstrates that regional sulcal depth is a sensitive marker for detecting alterations of cortical development in DS during fetal life, which may be associated with later neurocognitive impairment.

Endothelial dysfunction, with increased endothelin-1 (ET-1) synthesis, and sarcopenia, characterized by the loss of muscular mass and strength, are two aging–related conditions. However, a relationship between them has not been already established. The aim of this study was to determine whether ET-1 induces senescence and fibrosis in cultured murine myoblasts, which could be involved in the development of sarcopenia related to aging. For this purpose, myoblasts were incubated with ET-1 to assess cellular senescence, analyzed by senescence associated β-galactosidase activity and p16 expression; and fibrosis, assessed by fibronectin expression. ET-1 induced myoblast senescence and fibrosis through ETA receptor. The use of antioxidants and several antagonists revealed that ET-1 effect on senescence and fibrosis depended on ROS production and activation of PI3K-AKT-GSK pathway. To stress the in vivo relevance of these results, circulating ET-1, muscular strength, muscular fibrosis and p16 expression were measured in male C57Bl6 mice from 5-18-24-months-old. Old mice shown high levels of ET-1 correlated with muscular fibrosis, muscular p16 expression and loss of muscle strength. In conclusion, ET-1 promotes fibrosis and senescence in cultured myoblasts, similar results were found in old mice, suggesting a potential role for ET-1 in the development of sarcopenia related to aging.

BACKGROUND AND AIMS Sarcopaenia, defined as the loss of muscle mass and function, is an ageing-related pathology associated with some important diseases such as chronic kidney disease (CKD). Hyperphosphatemia has been associated with both, ageing and CKD. Old mice show an increase in serum phosphate concentration and a reduction in muscle mass, forelimb strength, gait speed and transition time in the static bar, with respect to young mice. Previous results of our group showed the beneficial effects of a low phosphate diet on ageing-related sarcopaenia. Given that the implementation of dietary phosphate restriction entails difficulties in the elderly, the aim of this work was to analyse the beneficial effects of a diet supplemented with a phosphate binder on the signs of sarcopaenia. METHOD C57BL6 male mice were used for in vivo studies: 5-month-old (young) and 24-month-old (old), which were fed with a powder standard diet (containing 0.6% of phosphate). Some old mice were fed with a hypophosphatemic diet (containing 0.2% of phosphate) or with a diet supplemented with 5% sucroferric oxyhydroxide (Velphoro®) for the last 3 months before sacrifice. Serum phosphate levels were analysed with a commercial kit. Muscle mass was estimated by measuring the gastrocnemius muscle mass divided by total body mass, muscle force was measured by a grip test and physical performance was evaluated by a gait test and the static bar test. RESULTS Velphoro® treated old mice showed a significant and more effective reduction in phosphate serum levels than old mice fed with the hypophosphatemic diet. No differences were observed in the relative gastrocnemius muscle mass between the three old mice experimental groups. By contrast, old mice fed with the standard diet supplemented with Velphoro® displayed an increased muscular strength and physical performance, improving the gait speed and reducing the transition time in the static bar, compared with old mice fed with the standard diet. Results obtained with Velphoro® treatment were similar to those observed in old mice fed with the hyphophosphatemic diet, but Velphoro® treatment achieve better results in motor coordination in the static bar test. CONCLUSION Dietary restriction of phosphate is a useful approach to mitigate the signs of ageing-related sarcopaenia (muscle strength and physical performance) in old mice. The use of Velphoro®, as a phosphate binder, exhibits similar or even better results than the hypophosphatemic diet. Therefore, the administration of Velphoro® could attenuate the signs of sarcopaenia in the elderly or in ageing-related diseases in which sarcopaenia is common, like CKD.

The severe acute respiratory syndrome CoV-2 rapidly spread worldwide, causing a pandemic. After a period of evolutionary stasis, a set of SARS-CoV-2 mutations has arisen in the spike, the leading glycoprotein at the viral envelope and the primary antigenic candidate for vaccines against the 2019 CoV disease (COVID-19). Here, we present comparative biochemical data of the glycosylated full-length ancestral and D614G spike together with three other highly transmissible strains classified by the World Health Organization as variants of concern (VOC): beta, gamma, and delta. By showing that only D614G early variant has less hydrophobic surface exposure and trimer persistence at mid-temperatures, we place D614G with features that support a model of temporary fitness advantage for virus spillover worldwide. Further, during the SARS-CoV-2 adaptation, the spike accumulates alterations leading to less structural rigidity. The decreased trimer stability observed for the ancestral and the gamma strain and the presence of D614G uncoupled conformations mean higher ACE-2 affinities when compared to the beta and delta strains. Mapping the energetic landscape and flexibility of spike variants is necessary to improve vaccine development.

Intestinal failure secondary to short bowel syndrome in pediatrics, is a rare condition with high morbimortality. A follow up multidisciplinary team is necessary to minimize complications and optimize the intestinal rehabilitation. There are no gold standard guidelines for the management of this group of complex patients. The development of clinical guidelines may contribute for an adequate management of patients with intestinal failure and short bowel syndrome. This Clinical Guideline for the Management was developed by 16 experts based on modified Delphi methodology. The meetings were held at the Argentinian Association of Enteral and Parenteral Nutrition (Asociacion Argentina de Nutricion Enteral y Parenteral); the topics analyzed were definitions, epidemiology, enteral and parenteral nutrition, pharmacological and surgical treatments, and criteria for referring patients to intestinal rehabilitation centers. The document is aimed to provide basic scientific knowledge for medical institutions, health providers, healthcare providers, patients and families.

Context Rare partial/complete loss-of-function mutations in the melanocortin-4 receptor (MC4R) gene are the most common cause of Mendelian obesity in European populations, but their contribution to obesity in the Mexican population is unclear. Objective and Design We investigated whether deleterious mutations in MC4R contribute to obesity in Mexican children and adults. Results We provide evidence that the MC4R p.Ile269Asn (rs79783591) mutation may have arisen in modern human populations from a founder event in native Mexicans. The MC4R Isoleucine 269 is perfectly conserved across 184 species, which suggests a critical role for the amino acid in MC4R activity. Four in silico tools (SIFT, PolyPhen-2, CADD, MutPred2) predicted a deleterious impact of the p.Ile269Asn substitution on MC4R function. The MC4R p.Ile269Asn mutation was associated with childhood (Ncontrols = 952, Ncases = 661, odds ratio (OR) = 3.06, 95% confidence interval (95%CI) [1.94–4.85]) and adult obesity (Ncontrols = 1445, Ncases = 2,487, OR = 2.58, 95%CI [1.52–4.39]). The frequency of the MC4R p.Ile269Asn mutation ranged from 0.52 to 0.59% and 1.53 to 1.59% in children and adults with normal weight and obesity, respectively. The MC4R p.Ile269Asn mutation co-segregated perfectly with obesity in 5 multigenerational Mexican pedigrees. While adults with obesity carrying the p.Ile269Asn mutation had higher BMI values than noncarriers, this trend was not observed in children. The MC4R p.Ile269Asn mutation accounted for a population attributable risk of 1.28% and 0.68% for childhood and adult obesity, respectively, in the Mexican population. Conclusion The MC4R p.Ile269Asn mutation may have emerged as a founder mutation in native Mexicans and is associated with childhood and adult obesity in the modern Mexican population.

Shotgun proteomics based on peptide fractionation by using liquid chromatography has become the common procedure for proteomic studies, although in the very beginning of the field, protein separation by using electrophoresis was the main tool. Nonetheless, during the last two decades, the electrophoretic techniques for peptide mixtures fractionation have evolved as a result of relevant technological improvements. We also proposed the combination of sodium dodecyl sulfate polyacrylamide gel electrophoresis for protein fractionation and sodium dodecyl sulfate free polyacrylamide gel electrophoresis for peptide separation as a novel procedure for proteomic studies. Here, we present an optimized device for sodium dodecyl sulfate free polyacrylamide gel electrophoresis improving peptide recoveries respect to the established electrophoretic technique off gel electrophoresis meanwhile conserving the excellent resolution described for the former technique in slab gel based systems. The device simultaneously allows the separation and the collection of fractionated peptides in solution.

In this article we will approach the movies Estrellas (2007) by Federico León and Marcos Martínez and Agarrando pueblo (1978) by the Colombian directors Luis Ospina and Carlos Mayolo. We are interested in analyzing the connection between the construction of space and poor bodys in documentaries that thematized the use of the marginalized spaces and the construction of an image of poverty that becomes the object of consume in the Latin American cinema.

Los objetivos de este trabajo son: (a) caracterizar cómo se han expresado las dinámicas de acaparamiento de tierras operadas en y desde los mundos agrarios de Argentina antes, durante y después del boom de precios internacionales de commodities, y (b) analizar los comportamientos empresariales desplegados particularmente después de ese boom. Basamos el análisis en datos primarios cualitativos y cuantitativos producidos en dos investigaciones: una sobre megaempresas de origen argentino, otra sobre la cúpula empresarial de una frontera de commodities del Gran Chaco. Concluimos que hay cambios recientes que sugieren tendencias hacia la intensificación de las escalas de capital en la agricultura, más que a la extensión de escalas de superficie.

Background Hyperphosphatemia has been related to the development of sarcopenia in aging mice. We describe the intracellular mechanisms involved in the impairment of the myogenic differentiation promoted by hyperphosphatemia and analyse these mechanisms in the muscle from older mice. Methods C2C12 cells were grown in 2% horse serum in order to promote myogenic differentiation, in the presence or absence of 10 mM beta‐glycerophosphate (BGP) for 7 days. Troponin T, paired box 7 (Pax‐7), myogenic factor 5 (Myf5), myogenic differentiation 1 (MyoD), myogenin (MyoG), myocyte enhancer factor 2 (MEF2C), P300/CBP‐associated factor (PCAF), histone deacetylase 1 (HDAC1), fibronectin, vimentin, and collagen I were analysed at 48, 72, and 168 h, by western blotting or by immunofluorescence staining visualized by confocal microscopy. Studies in mice were performed in 5‐ and 24‐month‐old C57BL6 mice. Three months before sacrifice, 21‐month‐old mice were fed with a standard diet or a low phosphate diet, containing 0.6% or 0.2% phosphate, respectively. Serum phosphate concentration was assessed by a colorimetric method and forelimb strength by a grip test. Fibrosis was observed in the tibialis anterior muscle by Sirius Red staining. In gastrocnemius muscle, MyoG, MEF2C, and fibronectin expressions were analysed by western blotting. Results Cells differentiated in the presence of BGP showed near five times less expression of troponin T and kept higher levels of Pax‐7 than control cells indicating a reduced myogenic differentiation. BGP reduced Myf5 about 50% and diminished MyoD transcriptional activity by increasing the expression of HDAC1 and reducing the expression of PCAF. Consequently, BGP reduced to 50% the expression of MyoG and MEF2C. A significant increase in the expression of fibrosis markers as collagen I, vimentin, and fibronectin was found in cells treated with BGP. In mice, serum phosphate (17.24 ± 0.77 mg/dL young; 23.23 ± 0.81 mg/dL old; 19.09 ± 0.75 mg/dL old with low phosphate diet) correlates negatively (r = −0.515, P = 0.001) with the muscular strength (3.13 ± 0.07 gf/g young; 1.70 ± 0.12 gf/g old; 2.10 ± 0.09 gf/g old with low phosphate diet) and with the expression of MyoG (r = −0.535, P = 0.007) and positively with the expression of fibronectin (r = 0.503, P = 0.001) in gastrocnemius muscle. The tibialis anterior muscle from old mice showed muscular fibrosis. Older mice fed with a low phosphate diet showed improved muscular parameters relative to control mice of similar age. Conclusions Hyperphosphatemia impairs myogenic differentiation, by inhibiting the transcriptional activity of MyoD, and enhances the expression of fibrotic genes in cultured myoblasts. Experiments carried out in older mice demonstrate a close relationship between age‐related hyperphosphatemia and the decrease in the expression of myogenic factors and the increase in factors related to muscle fibrosis.

Obesity can lead children and adolescents to an increased cardiovascular disease (CVD) risk. A diet supplemented with Plantago psyllium has been shown to be effective in reducing LDL-C and IL-6 in adolescents. However, there are no studies that have explored small-dense LDL (sdLDL) or HDL subclasses. The aim of this study was to evaluate the impact of a fiber dietary intervention on LDL and HDL subclasses in adolescents with obesity. In this parallel, double blind, randomized clinical trial, the participants were assigned to Plantago psyllium or placebo (10g/day for 7 weeks). We randomized 113 participants, and evaluated and analyzed 100 adolescents (50 in each group), 15 to 19 years with a body mass index of 29-34. We measured biochemical markers LDL and HDL subclasses using the Lipoprint system (Quantimetrix) and IL-6 by ELISA. Post-treatment there was a decrease in sdLDL between the groups 2.0 (0-5.0) vs 1 (0-3.0) mg/dl (p = 0.004), IL-6 median 3.32 (1.24-5.96) vs 1.76 (0.54-3.28) pg/ml, p0.0001. There were no differences in HDL subclasses and no adverse effects were reported in either group.Conclusions: Small dense LDL and IL-6 reduced in adolescents with obesity when consuming Plantago psyllium. This may be an early good strategy for the reduction of cardiovascular disease risk in this vulnerable population.Trial registration: ISRCTN # 14180431. Date assigned 24/08/2020 What is Known: • Supplementing the diet with Plantago psyllium lowers LDL-C levels. What is New: • First evidence that soluble fiber supplementation like Plantago psyllium decreases small dense LDL particles in association with lowered IL-6, reducing the risk of cardiovascular disease in obese adolescents.

Intestinal failure secondary to short bowel syndrome in pediatrics, is a rare condition with high morbimortality. A follow up multidisciplinary team is necessary to minimize complications and optimize the intestinal rehabilitation. There are no gold standard guidelines for the management of this group of complex patients. The development of clinical guidelines may contribute for an adequate management of patients with intestinal failure and short bowel syndrome. This Clinical Guideline for the Management was developed by 16 experts based on modified Delphi methodology. The meetings were held at the Argentinian Association of Enteral and Parenteral Nutrition (Asociación Argentina de Nutrición Enteral y Parenteral); the topics analyzed were definitions, epidemiology, enteral and parenteral nutrition, pharmacological and surgical treatments, and criteria for referring patients to intestinal rehabilitation centers. The document is aimed to provide basic scientific knowledge for medical institutions, health providers, healthcare providers, patients and families.La falla intestinal secundaria a síndrome de intestino corto en pediatría es una entidad poco frecuente, de alta morbimortalidad. Requiere de un equipo interdisciplinario para su abordaje, lo cual ha demostrado que disminuye la morbimortalidad y aumenta la posibilidad de que los pacientes logren la autonomía intestinal. Existe una falta de evidencia científica en diferentes abordajes de la patología. Consideramos necesario el desarrollo de esta Guía para el Manejo Clínico construida sobre la base de la metodología Delphi modificada, en la Asociación Argentina de Nutrición Enteral y Parenteral, por 16 expertos que se reunieron para discutir y consensuar los principales aspectos de tratamiento clínico. Se analizaron 4 aspectos: definiciones y epidemiología; nutrición enteral, nutrición parenteral; tratamientos farmacológicos y quirúrgicos, y criterios de derivación a centros de alta complejidad. Sin duda este documento será de utilidad para los pacientes, los profesionales y las instituciones, así como para los diferentes financiadores del sistema de salud.

En este trabajo nos proponemos abordar 143.353 (los ojos no quieren estar siempre cerrados) (2010) del artista español Marcelo Expósito. Su obra funda un dispositivo crítico que plantea una serie de preguntas en torno a lo que se podría llamar una ética de la mirada. En 143.353… se anudan una perspectiva documental experimental y archivística, de modo que la imagen y el archivo devienen arte de la memoria. Definidos como “archivos mutantes” (GARCÍA, 2018), los videos de Expósito dan cuenta de un posicionamiento singular en relación con la política, la historia y la estética. Sus procedimientos más potentes consisten en el montaje y la organización de imágenes de naturaleza variada y de temporalidades heterogéneas. El artista propone nuevas matrices de citación y yuxtaposición en las que aparecen pliegues que tienden a una restauración de la experiencia para activar la memoria. Su posición denota la denuncia de una política de la invisibilidad en la cual la imagen opera como un instrumento mediante el cual la anomia colectiva, la amnesia y la represión son socialmente inscriptas.Palabras clave: Archivo; memoria; imagen; desaparecidos; dictadura.

Background and Aims Hyperphosphatemia has been associated with aging and chronic kidney disease (CKD). Sarcopenia, which is a related condition of these pathologies, is defined by loss of force and muscular mass. During aging, chronic systemic inflammation appears, termed inflammaging, due to changes in immune system function. Inflammaging has been associated with many age-related diseases including Sarcopenia and CKD. The work aimed to evaluate the effect of hyperphosphatemia on proinflammatory profile of cultured myoblast cells and to analyze, in old mice, the effect of a dietary restriction in the phosphate intake on the aging-related sarcopenia. Methods Culture murine myoblast C2C12 cells were used for in vitro experiments. Cells were treated with 10 mM beta-glycerophosphate (BGP) as phosphate donor for 24, 48 or 72h. Inflammation was assessed through IL6, TNFα and MCP-1 expression by RT-qPCR. Twenty-four months old, C57BL6 mice were used for in vivo studies. Mice were fed with a normal diet containing 0.6% of phosphate until 21 months, after that, one group of mice continued with a normal diet and the other group was fed with a hypophosphatemic diet, containing a 0.2% of phosphate, for the following 3 months. Old mice were compared with 5 months old mice. Muscle force was measured by a grip strength test. Serum phosphate concentration was evaluated with a commercial kit and inflammation was assessed through IL-1β expression levels by RT-qPCR. Results Results showed that BGP treatment augmented pro-inflammatory cytokines levels, in myoblast, at 72h. On the other hand, old mice had a 40% increase in serum phosphate concentration regarding young mice, and, in parallel, they showed a reduction in forelimb strength. Old animals feeding with a hypophosphatemic diet showed a decreased level of phosphate serum linked to a better muscle function. Pro-inflammatory cytokines expression was higher in old mice compared to young mice; those values were reduced in 24-month-mice fed with a low phosphate diet. Furthermore, there was a positive correlation between IL-1β expression levels and serum phosphate levels, suggesting that high levels of serum phosphate were increasing inflammation in vivo and a negative correlation between IL-1β and grip strength test, which shows that high levels of inflammation decrease muscular function Conclusion In this work, we propose that high levels of phosphate are related to inflammation in vitro and in vivo. This increase of proinflammatory cytokines decreases muscle function whereas dietary restriction of phosphate decreases inflammation and improves muscle function. These results could point to a direct link between elevated serum phosphate levels and inflammaging presented in sarcopenic people such as CKD patients and aged people.

Background and Aims Patients with chronic kidney disease (CKD) present a high rate of cardiovascular mortality mainly associated with endothelial dysfunction, which causes more cardiovascular events in presence of atherosclerosis. Atherosclerosis is characterized by a significant increase of low density lipoproteins (LDL), reactive oxygen species (ROS) and inflammation. ROS can oxidize LDL generating oxidized-LDL (oxLDL) that promotes the development of cardiovascular pathologies. The aim of this study was to evaluate whether oxLDL induce endothelial dysfunction analysing the involvement of vascular fibrosis. Method The model used for in vivo studies was the Knockout apolipoprotein E (KO-apoE) mice, which resemble human atherosclerosis and shown high levels of cholesterol (LDL) that can be oxidized to oxLDL. In mice, blood pressure was registered before sacrificed them. After that, we measured different parameters as serum cholesterol levels, vascular function by vascular reactivity in mesenteric arteries and vascular fibrosis in aorta by Sirius Red staining and by the protein expression of fibronectin and collagen-I by immunohistochemistry. In order to investigate the mechanism of action of oxLDL, in vitro studios were performed on human smooth muscle cells (SMC) incubated with oxLDL at different times. Fibrosis was evaluated by the expression of TGF- β and extracellular matrix proteins such as fibronectin and collagen-I by Western blot and by immunofluorescence. ROS production was also measured by fluorescence confocal microscopy, using the CellROX Deep Red probe. Results KO-apoE mice shown higher levels of serum cholesterol and blood pressure than WT animals. Moreover, KO-apoE mice showed endothelial dysfunction since their arteries were less relaxed and more contracted. In addition, these mice presented thickening of vascular wall (SMC layer), more fibrosis showing intense Sirius Red staining and less expression of elastin, all compatible with their vascular dysfunction compared to WT mice. Furthermore, aortas from KO-apoE mice showed a slight increase in fibronectin and collagen-I expression assessed by immunohistochemistry. In vivo studies were confirmed in vitro after treating SMC with oxLDL. oxLDL induced fibrosis in SMC by increasing TGF-β, fibronectin and collagen-I protein expressions evaluated by Western blot and immunofluorescence assays. Treatment with oxLDL also increased ROS production, which seem to be responsible of oxLDL-induced fibrosis in human SMC, as it was blocked in the presence of the antioxidant N-Acetyl-cysteine. Conclusion In summary, these results point to endothelial dysfunction associated to atherosclerosis (oxLDL) could be mediated by an increase in the development of vascular fibrosis where ROS could play an important role. Therefore, the endothelial dysfunction typical of CKD patients could impair with more vascular fibrosis when atherosclerosis is also present.

Background and Aims The loss of muscle mass and function has been related to chronic kidney disease (CKD). About 37% of dialysis patients show symptoms of sarcopenia and this has been related to an increased risk of mortality. Changes in sarcopenic muscle include the loss of its regenerative capacity due to a reduction in the number and function of satellite cells, the muscle stem cells. The concentration of serum uremic toxins (UT) increases in parallel to a decline in the glomerular filtration rate in patients with CKD and this uremia may be involved in the development of sarcopenia. Previous studies showed as serum concentration of UT found in the early stages of CKD inhibits myogenic differentiation of cultured myoblasts. Nevertheless, the effect of those concentrations found in the advanced stages of CKD has not been described. The study aimed to analyse whether UT affect the muscular regeneration process by modifying the proliferation capacity of myoblasts (activated satellite cells). Method Cultured mouse myoblasts C2C12 cells were used for all experiments. Cells were grown with 0% or 10% FBS culture media in the presence or absence of indoxyl sulphate and para-cresol at doses of 100µg/ml each one, which are similar to ones found in the advanced stages of CKD. Proliferation was evaluated by scratch wound healing and cell cycle by flow cytometry with propidium iodide and the fluorescent probe CFSE, an intracellular protein binding dye that is divided equally between daughter cells, allowing the discrimination of successive rounds of cell division. Chromosome condensation was assessed by immunofluorescence staining by confocal microscopy. Apoptosis was analysed by annexin V staining. Results C2C12 cells treated with UT shown a significant decrease in the proliferation rate. A significant delay in wound closure was observed in cells treated with UT compared to control cells. Myoblasts treated with UT suffered a significant decrease in the proliferation rate since the probe remained higher than in the vehicle-treated cells. Proliferating cells treated with UT suffered a dramatic cell cycle arrest between the phases S and G2/M. Chromosome condensation was also analysed, finding that in the presence of colcemid, vehicle-treated cells condensed their chromosomes, as expected, whereas UT-treated cells did not, suggesting that UT stop the cell cycle at any point before the entry of cells in the mitosis phase. Besides, there was strong phosphorylation of cdc2 in the presence of UT indicating that cdc2 and the complex cdc2-cyclin B were inactive. This result explains why cells did not enter in the mitosis phase under UT exposition. Finally, UT induced the death of proliferating C2C12 cells by apoptosis. Conclusion In the advanced stages of CKD, uremic toxins concentration increases, thereby inducing a dramatic arrest in the cell cycle of myoblasts, inactivating the cdc2-cyclin B complex, interrupting their proliferation and leading them towards cell apoptosis. These results point to a role of uremic toxins impairing the skeletal muscle regeneration process, which could be involved in CKD-related sarcopenia and frailty.

Zika virus (ZIKV) transmission to the fetus during pregnancy could enable a collection of severe fetal malformations like microcephaly (MC), termed Congenital Zika Syndrome (CZS). The mechanisms involved in ZIKV transplacental transmission are not fully understood. Here we aim to identify in placental tissues the deregulated proteins associated with ZIKV-induced MC using label-free proteomics. We found proteins associated with DNA damage and gene expression inhibition up-regulated in infected placentas with no MC fetuses (Z+) compared to the control group (Ctr) Actin filament organization and the immune response were also found deregulated in the Z+ group. In ZIKV-positive placentas bearing fetuses with MC (MC+) was detected an increase in T cell activation, indicating an elevated immune response. A comparison between MC+ and Z+ groups showed a higher abundance of proteins related to endocytosis and autophagy in MC+, suggesting a higher transcytosis of vesicles with ZIKV particles across the maternal-fetal interface. Our results suggest that higher expression of integrins in MC+ might be associated with high internalization of the virus since these proteins are known as virus receptors. Similarly, an increased immune response in the placenta and higher infiltration of the virus to the fetus could contribute to the neurological malformation of the CZS. This article is protected by copyright. All rights reserved.

Summary Hyperphosphatemia is related to some pathologies, affecting vascular cell behavior. This work analyzes whether high concentration of extracellular phosphate induces endothelial senescence through up-regulation of endothelin-1 (ET-1), exploring the mechanisms involved. The phosphate donor β-glycerophosphate (BGP) in human endothelial cells increased ET-1 production, endothelin-converting enzyme-1 (ECE-1) protein, and mRNA expression, which depend on the AP-1 activation through ROS production. In parallel, BGP also induced endothelial senescence by increasing p16 expression and the senescence-associated β-galactosidase (SA-s-GAL) activity. ET-1 itself was able to induce endothelial senescence, increasing p16 expression and SA-s-GAL activity. In addition, senescence induced by BGP was blocked when different ET-1 system antagonists were used. BGP increased ROS production at short times, and the presence of antioxidants prevented the effect of BGP on AP1 activation, ECE-1 expression, and endothelial senescence. These findings were confirmed in vivo with two animal models in which phosphate serum levels were increased: seven/eight nephrectomized rats as chronic kidney disease models fed on a high phosphate diet and aged mice. Both models showed hyperphosphatemia, higher levels of ET-1, and up-regulation in aortic ECE-1, suggesting a direct relationship between hyperphosphatemia and ET-1. Present results point to a new and relevant role of hyperphosphatemia on the regulation of ET-1 system and senescence induction at endothelial level, both in endothelial cells and aorta from two animal models. The mechanism involved showed a higher ROS production, which probably activates AP-1 transcription factor and, as a result, ECE-1 expression, increasing ET-1 synthesis, which in consequence induces endothelial senescence.

Este artículo aborda el estudio del agronegocio a partir de las prácticas de las megaempresas de producción agropecuaria de origen argentino, que contribuyen a dar forma y a consolidar los pilares sobre los que se asienta ese modelo productivo. En particular, el análisis de las prácticas productivas, comerciales y financieras de estas empresas "tanto en Argentina como en los otros países del Mercosur donde se expandieron" permite entender el vínculo entre los pilares financiero, productivo y organizacional de esta lógica de producción. A través del estudio de dos casos, el Grupo Los Grobo y El Tejar, se analiza la flexibilización de la producción y del trabajo que promueven estas empresas con su modelo de negocios en 'red', su participación en la financiarización de la agricultura, y el vínculo de ambos aspectos con los procesos de concentración que facilitan. This article deals with the study of agribusiness based on the practices of agricultural production mega-companies of Argentinean origin, which contribute to shaping and consolidating the pillars on which this productive model stands. In particular, the analysis of the productive, commercial and financial practices of these companies "not only in Argentina but also in the other Mercosur countries where they expanded their production" allows us to understand the link between the financial, productive and organizational pillars of this logic of production. Through the study of two cases, Los Grobo Group and El Tejar, we analyze the flexibilization of production and labor these companies promote through their "network" business model, their part in financialization of agriculture, and the relationship of both traits to the concentration processes they facilitate.

In recent years, the evidence has demonstrated the relevance of the gut microbiota in an individual's health. The dynamics of an early colonization and the establishment of a community of plenty, diverse, and healthy microorganisms from a vaginal delivery and breastfeeding are critical for the development of a healthy immune matrix. The objective of this review is to describe the available evidence on microbiota development in the first year of life and the current possibilities offered by prebiotics, probiotics, symbiotics, and postbiotics during such critical stage of life.En los últimos años, las evidencias han demostrado la importancia de la microbiota intestinal en la salud del individuo. La dinámica de la colonización temprana y el establecimiento de una comunidad abundante y diversa de microorganismos saludables, a partir de un parto vaginal y lactancia materna, resultan fundamentales en la conformación de una matriz inmunológica saludable. Esta revisión tiene como objetivo describir las evidencias disponibles sobre el desarrollo de la microbiota en el primer año de vida y el actual potencial que ofrece el uso de prebióticos, probióticos, simbióticos y posbióticos durante esta etapa esencial de la vida.