Quantitative RNA-seq Analysis Unveils Osmotic and Thermal Adaptation Mechanisms Relevant for Ectoine Production in Chromohalobacter salexigens

Quantitative RNA sequencing (RNA-seq) and the complementary phenotypic assays were implemented to investigate the transcriptional responses of Chromohalobacter salexigens to osmotic and heat stress. These conditions trigger the synthesis of ectoine and hydroxyectoine, two compatible solutes of biotechnological interest. Our findings revealed that both stresses make a significant impact on C. salexigens global physiology. Apart from compatible solute metabolism, the most relevant adaptation mechanisms were related to “oxidative- and protein-folding- stress responses,” “modulation of respiratory chain and related components,” and “ion homeostasis.” A general salt-dependent induction of genes related to the metabolism of ectoines, as well as repression of ectoine degradation genes by temperature, was observed. Different oxidative stress response mechanisms, secondary or primary, were induced at low and high salinity, respectively, and repressed by temperature. A higher sensitivity to H2O2 was observed at high salinity, regardless of temperature. Low salinity induced genes involved in “protein-folding-stress response,” suggesting disturbance of protein homeostasis. Transcriptional shift of genes encoding three types of respiratory NADH dehydrogenases, ATP synthase, quinone pool, Na+/H+ antiporters, and sodium-solute symporters, was observed depending on salinity and temperature, suggesting modulation of the components of the respiratory chain and additional systems involved in the generation of H+ and/or Na+ gradients. Remarkably, the Na+ intracellular content remained constant regardless of salinity and temperature. Disturbance of Na+- and H+-gradients with specific ionophores suggested that both gradients influence ectoine production, but with differences depending on the solute, salinity, and temperature conditions. Flagellum genes were strongly induced by salinity, and further induced by temperature. However, salt-induced cell motility was reduced at high temperature, possibly caused by an alteration of Na+ permeability by temperature, as dependence of motility on Na+-gradient was observed. The transcriptional induction of genes related to the synthesis and transport of siderophores correlated with a higher siderophore production and intracellular iron content only at low salinity. An excess of iron increased hydroxyectoine accumulation by 20% at high salinity. Conversely, it reduced the intracellular content of ectoines by 50% at high salinity plus high temperature. These findings support the relevance of iron homeostasis for osmoadaptation, thermoadaptation and accumulation of ectoines, in C. salexigens.España Ministerio de Economía y Competitividad BIO2015-63949-RJunta de Andalucía P11-CVI-729

Changes in colony morphology and antibiotic resistance in response to in vitro exposure of Klebsiella pneumoniae to the antibiotic cephalothin

Klebsiella pneumoniae is a gram-negative nosocomial pathogen and causative agent of many hospital acquired infections. K. pneumoniae infections have become increasingly of interest due to the rise of hypervirulent variants and multidrug resistant strains. Modeling how antibiotic resistance evolves in K. pneumoniae will allow us to better understand exactly how the bacterium acquires resistance to various antibiotics. A previous experiment in our lab exposed a strain of K. pneumoniae to low but increasing concentrations of the antibiotic cephalothin. As a result, the strain evolved to be mucoid with elongated cellular morphology and resistant to multiple antibiotics. This study aimed to repeat the same experimental approach with multiple cultures, to determine if different genomic mutations could result in the same endpoint of antibiotic resistance. Five cultures of K. pneumoniae 43816 were exposed to increasing amounts of the antibiotic cephalothin over a 14-day period. After the 14 day experiment, cultures were assayed for changes in antibiotic susceptibility, colony, and cellular-level morphology. Preliminary results indicate evolved resistance to cephalothin and tetracycline, but not kanamycin. Further, alterations in the colony morphology have been noted with a mix of small and large colony phenotypes. This variation of colony morphology in the adapted population may indicate different genetic mutations that correspond to these large and small colony variants. Current work is determining the relationship between colony morphology and antibiotic resistance

Crossroads of Cuisine

Crossroads of Cuisine provides a history of foods, and foodways in terms of exchanges taking place in Central Asia and in surrounding areas such as China, Korea or Iran during the last 5000 years, stressing the manner in which East and West, West and East grew together through food. It provides a discussion of geographical foundations, and an interlocking historical and cultural overview going down to the present day, with a comparative country by country survey of foods and recipes. An ethnographic photo essay embracing all parts of the book binds it all together, and helps make topics discussed vivid and approachable. The book is important for explaining key relationships that have not always been made clear in past scholarship

Engineering physiological environments to advance kidney organoid models from human pluripotent stem cells

During embryogenesis, the mammalian kidney arises because of reciprocal interactions between the ureteric bud (UB) and the metanephric mesenchyme (MM), driving UB branching and nephron induction. These morphogenetic processes involve a series of cellular rearrangements that are tightly controlled by gene regulatory networks and signaling cascades. Here, we discuss how kidney developmental studies have informed the definition of procedures to obtain kidney organoids from human pluripotent stem cells (hPSCs). Moreover, bioengineering techniques have emerged as potential solutions to externally impose controlled microenvironments for organoid generation from hPSCs. Next, we summarize some of these advances with major focus On recent works merging hPSC-derived kidney organoids (hPSC-kidney organoids) with organ-on-chip to develop robust models for drug discovery and disease modeling applications. We foresee that, in the near future, coupling of different organoid models through bioengineering approaches will help advancing to recreate organ-to-organ crosstalk to increase our understanding on kidney disease progression in the human context and search for new therapeutics

La raza en la literatura : Alborada de Iris y la Retórica de la Modernidad en una escritora de vanguardia. Chile, 1930-1946

La tesis de doctorado titulada “La Raza en la Literatura: Alborada de Iris y la Retórica de la Modernidad en una escritora de Vanguardia. Chile, 1930-1946” surge de la pregunta ¿cómo, en qué contexto y por qué es utilizado el concepto raza en una serie de novelas histórico-memorialísticas (Alborada) publicadas en la primera mitad del siglo XX por una escritora de la aristocracia chilena conocida como Iris? La emergencia de esta pregunta y el planteamiento de este problema de investigación hacen parte de una reflexión sobre las formas discursivas que se dieron dentro de la literatura e historiografía chilena entre 1870 y 1950. Las referencias al pasado colonial o decimonónico silenciaron o soslayaron narrar la conformación social chilena en su plena complejidad cultural y fenotípica. En gran parte de los textos que circulaban en la época, especialmente en el paso del siglo XIX al XX, la palabra raza se estableció como un concepto explicativo de muchos fenómenos. El Giro Intelectual que aconteció en América Latina, ligado a un movimiento intelectual global en el que confluyeron contradictorias posturas muchas veces usando un lenguaje similar, se caracterizó por dos ejes fundamentales: un cuestionamiento a las concepciones científico-positivistas fuertemente divulgadas en la segunda mitad del siglo XIX encadenadas a la emergencia de ideas espiritualistas, y por otro lado, un reforzamiento de las explicaciones deterministas de los fenómenos sociales, a partir de datos y conceptos como la raza, el clima, la geografía o la psicología. No obstante, y en definitiva ¿qué es raza en todos estos discursos? Este es un asunto esencial que se dilucida a lo largo de este trabajo. Junto a las preguntas planteadas, se pretende indagar sobre las estrategias discursivas que utiliza la obra Alborada para perfilar una (nueva) propuesta de identidad nacional chilena –genealógica e intelectual– mediante la utilización de conceptos que se relacionan con campos semánticos de lo femenino, lo moderno y la vanguardia, la espiritualidad y el evolucionismo, para llegar a descubrir de qué modo se liga la Retórica de la Modernidad presente en su discurso –retórica definida por el pensamiento Decolonial, como veremos– con el Feminismo y el Espiritualismo de Vanguardia, dos tendencias o lenguajes literarios al que adscribió Iris. La metodología, junto al sustento teórico, se ha tomado de diversos autores, tanto del área de los estudios literarios y de los estudios culturales como de los estudios históricos. Por lo tanto esta tesis es una propuesta esencialmente interdisciplinaria. A partir de esta base, y mediante la lectura a contrapunto, sociocrítica y decolonial, de las novelas de Iris se ha podido concluir que la obra de esta autora representa un complejo escenario discursivo, que se mueve entre el progresismo del feminismo y la vanguardia, pero que, a la vez, apropia un lenguaje ajustado a los discursos imperialistas y cientificistas decimonónicos. En última instancia, la gran influencia de la Teosofía en la escritura de Iris genera el lenguaje alegórico y profético, espiritual y visionario que contienen las novelas que conforman Alborada, todo cruzado por la ideología racial.A tese de doutoramento intitulada “A Raça na Literatura: Alborada, de Iris, e a Retórica da Modernidade numa escritora de Vanguarda. Chile, 1930-1946” surge da questão: como, em que contexto e por que motivo é usado o conceito de raça numa série de romances histórico-memorialísticos (Alborada) publicados na primeira metade do século XX por uma escritora da aristocracia chilena, conhecida como Iris? O surgimento desta questão e a abordagem deste problema de pesquisa, fazem parte de uma reflexão sobre as formas discursivas que ocorreram na literatura e na historiografia chilena entre 1870 e 1950. Nestes discursos, as referências ao passado colonial ou ao século XIX silenciaram ou ignoraram a conformação social chilena em toda a sua complexidade cultural e fenotípica. Na maior parte dos textos que circulavam na época, especialmente na passagem entre os séculos XIX e XX, a palavra raça foi estabelecida como um conceito explicativo de muitos fenómenos. A Viragem Intelectual que aconteceu na América Latina, ligada a um movimento intelectual global onde confluíram posições contraditórias muitas vezes utilizando linguagem semelhante, caracterizou-se por dois pilares principais: um desafio das concepções científicas positivistas fortemente divulgadas na segunda metade do século XIX ligadas à emergência de ideias espiritualistas, e por outro lado, um reforço das explicações deterministas dos fenómenos sociais, a partir de dados e conceitos como raça, clima, geografia ou psicologia. No entanto, e concretamente, o que é a raça em todos estes discursos? Esta é uma questão essencial que se elucida ao longo deste trabalho. Juntamente com as questões levantadas, procura-se investigar as estratégias discursivas utilizadas pela obra Alborada para delinear uma (nova) proposta de identidade nacional chilena –genealógica e intelectual– mediante a utilização de conceitos que se relacionam com os campos semânticos do feminino, o moderno e a vanguarda, espiritualidade e evolucionismo, para esclarecer como a Retórica da Modernidade –uma retórica definida pelo pensamento Descolonial, como veremos– está ligada discursivamente com o Feminismo e o Espiritualismo de Vanguarda, duas tendências ou linguagens literárias às quais Iris aderiu. A metodologia, juntamente com o suporte teórico, foi tomada de vários autores, tanto na área dos estudos literários e dos estudos culturais como dos estudos históricos. Portanto, esta tese é uma proposta essencialmente interdisciplinar. A partir dessa base, e através da leitura em contraponto, sociocrítica e descolonial dos romances de Iris, foi possível concluir que o trabalho desta autora representa um cenário discursivo complexo, que se move entre o progressismo do feminismo e a vanguarda, mas que, ao mesmo tempo, se apropria de uma linguagem dos discursos imperialista e científico do século XIX. Em última análise, a grande influência da Teosofia na escrita de Iris gera a linguagem alegórica e profética, espiritual e visionária, presente nos romances que compõem Alborada, todos atravessados pela ideologia racial.This doctoral dissertation titled “The Race in Literature: Alborada by Iris and the Rhetoric of Modernity in an Avant-garde Writer. Chile, 1930-1946” arises from the question: how, in what context and why is the concept of race used in a series of historical-memorialistic novels (Alborada) published in the first half of the 20th century by a Chilean aristocrat writer known as Iris? The emergence of this question and the approach to this research problem are part of a reflection on the discursive forms of Chilean literature and historiography between 1870 and 1950, where references to the Colonial past or to the 19th century ignored the Chilean social conformation in its cultural and phenotypic complexity. In many texts that circulated at the time, especially in the turn of the 19th to the 20th century, the word race was established as an explanatory concept to many phenomena. The Intellectual Turn developed in Latin America, linked to a global intellectual movement in which converged contradictory positions often using a similar language, was characterized by two fundamental axes: first, a disbelief in the scientific-positivist conceptions widely disseminated in the second half of the 19th century, connected to the emergency of spiritualist ideas; and, on the other hand, a reinforcement of the deterministic explanations of social phenomena, considering data and concepts such as race, climate, geography or psychology. However, and finally, what is race in all these discourses? This is an essential issue that is elucidated throughout this thesis. In addition to these questions, we intend to investigate the discursive strategies used by the novels Alborada to outline a (new) proposal of Chilean national identity –genealogical and intellectual– through the use of concepts associated to the semantic fields of the Feminine, the Modernity and the Avant-garde, Spirituality and Evolutionism; this way, we will explain how we may connect the Rhetoric of Modernity – a rhetoric defined by Decolonial thought, as we will see– with Feminism and Avant-garde Spiritualism, two literary languages or tendencies which Iris favored. The methodology and the theoretical support have been taken from various authors from different areas such as literary studies, cultural studies and historical studies. Therefore this dissertation is an essentially interdisciplinary proposal. From this base, and through the counterpoint, the sociocritic and the decolonial reading of Iris’ novels, it has been possible to conclude that the work by this author represents a complex discursive scenario, which moves between the progressivism of feminism and the avant-garde, but at the same time, appropriates the language of the 19th century imperialist and scientific discourses. Ultimately, the great influence of Theosophy in the writing by Iris generates the allegorical and prophetic, spiritual and visionary language that appears in the novels of Alborada, all crossed by racial ideology

Impact of diet on cardiometabolic health in children and adolescents

The manifestation of cardiovascular risk factors, such as hypertension, diabetes, and particularly obesity begins in children and adolescents, with deleterious effects for cardiometabolic health at adulthood. Although the impact of diet on cardiovascular risk factors has been studied extensively in adults, showing that their cardiometabolic health is strongly lifestyle-dependent, less is known about this impact in children and adolescents. In particular, little is known about the relationship between their dietary patterns, especially when derived a posteriori, and cardiovascular risk. An adverse association of cardiovascular health and increased intake of sodium, saturated fat, meat, fast food and soft drinks has been reported in this population. In contrast, vitamin D, fiber, mono-and poly-unsaturated fatty acids, dairy, fruits and vegetables were positively linked to cardiovascular health. The aim of this review was to summarize current epidemiological and experimental evidence on the impact of nutrients, foods, and dietary pattern on cardiometabolic health in children and adolescents. A comprehensive review of the literature available in English and related to diet and cardiometabolic health in this population was undertaken via the electronic databases PubMed, Cochrane Library, and Medline

Fructose metabolism in Chromohalobacter salexigens: interplay between the Embden–Meyerhof–Parnas and Entner–Doudoroff pathways

Background The halophilic bacterium Chromohalobacter salexigens metabolizes glucose exclusively through the Entner–Doudoroff (ED) pathway, an adaptation which results in inefficient growth, with significant carbon overflow, especially at low salinity. Preliminary analysis of C. salexigens genome suggests that fructose metabolism could proceed through the Entner–Doudoroff and Embden–Meyerhof–Parnas (EMP) pathways. In order to thrive at high salinity, this bacterium relies on the biosynthesis and accumulation of ectoines as major compatible solutes. This metabolic pathway imposes a high metabolic burden due to the consumption of a relevant proportion of cellular resources, including both energy molecules (NADPH and ATP) and carbon building blocks. Therefore, the existence of more than one glycolytic pathway with different stoichiometries may be an advantage for C. salexigens. The aim of this work is to experimentally characterize the metabolism of fructose in C. salexigens. Results Fructose metabolism was analyzed using in silico genome analysis, RT-PCR, isotopic labeling, and genetic approaches. During growth on fructose as the sole carbon source, carbon overflow was not observed in a wide range of salt concentrations, and higher biomass yields were reached. We unveiled the initial steps of the two pathways for fructose incorporation and their links to central metabolism. While glucose is metabolized exclusively through the Entner–Doudoroff (ED) pathway, fructose is also partially metabolized by the Embden–Meyerhof–Parnas (EMP) route. Tracking isotopic label from [1-13C] fructose to ectoines revealed that 81% and 19% of the fructose were metabolized through ED and EMP-like routes, respectively. Activities of enzymes from both routes were demonstrated in vitro by 31P-NMR. Genes encoding predicted fructokinase and 1-phosphofructokinase were cloned and the activities of their protein products were confirmed. Importantly, the protein encoded by csal1534 gene functions as fructose bisphosphatase, although it had been annotated previously as pyrophosphate-dependent phosphofructokinase. The gluconeogenic rather than glycolytic role of this enzyme in vivo is in agreement with the lack of 6-phosphofructokinase activity previously described. Conclusions Overall, this study shows that C. salexigens possesses a greater metabolic flexibility for fructose catabolism, the ED and EMP pathways contributing to a fine balancing of energy and biosynthetic demands and, subsequently, to a more efficient metabolism.University of Murcia and University of Seville was supported by projects: BIO2015-63949-R, BIO2014-54411-C2-1-REuropa MINECO/FEDER RTI2018-094393-B-C21Fundación Séneca (Grant no. 19236/PI/14

Neodymium 1D systems: targeting new sources for field-induced slow magnetization relaxation

Two non-isostructural homometallic 1D neodymium species dis- playing field-induced slow magnetization relaxations are presented together with theoretical studies. It is established that both systems are better described as organized 1D single molecule magnets (SMMs). Studies show great potential of NdIII ions to provide homometallic chains with slow magnetic relaxation

Kinetic model of photo-Fenton degradation of paracetamol in an annular reactor: main reaction intermediates and cytotoxicity studies

A kinetic model derived from a simplified reaction sequence is proposed for the photo-Fenton degradation of Paracetamol (PCT), employing an annular photoreactor. The kinetic model explicitly included the effects of radiation absorption on pollutant degradation kinetics through the evaluation of the Local Volumetric Rate of Photon Absorption (LVRPA). Irradiated experiments achieved an average PCT conversion of 99.3% at 5 min of reaction, and a maximum of 69% of mineralization. Conversely, non-irradiated experiments reached an average PCT conversion of 86.6% at 5 min of reaction, and a maximum of 35% of mineralization. Kinetic parameters (, ,M-1s-1) were estimated employing a nonlinear, multi-parameter regression method, and the validated kinetic model was used to predict temporal variations of the concentrations of HP, PCT, and the main reaction intermediates: hydroquinone (HQ) and 1,4-benzoquinone (BQ). The root mean square error (RMSE) values obtained for HP, PCT, HP, HQ and BQ were 1.16¿×¿10-2, 7.13¿×¿10-1, 3.53¿×¿10-3, 3.05¿×¿10-3 mM, respectively, showing a good agreement between experimental and predicted data. Moreover, the kinetic model was validated with a new set of experimental tests, confirming its predictive capacity. Beyond the degree of mineralization attained, additional cytotoxicity tests proved that the photo-Fenton process is effective in generating a non-toxic effluent under the operating variables investigated.Peer ReviewedPostprint (published version