Rapid depletion of "catch-and-release" anti-ASGR1 antibody in vivo.

Targeting antigens with antibodies exhibiting pH/Ca2+-dependent binding against an antigen is an attractive strategy to mitigate target-mediated disposition and antigen buffering. Studies have reported improved serum exposure of antibodies exhibiting pH/Ca2+-binding against membrane-bound receptors. Asialoglycoprotein receptor 1 (ASGR1) is a membrane-bound receptor primarily localized in hepatocytes. With a high expression level of approximately one million receptors per cell, high turnover, and rapid recycling, targeting this receptor with a conventional antibody is a challenge. In this study, we identified an antibody exhibiting pH/Ca2+-dependent binding to ASGR1 and generated antibody variants with increased binding to neonatal crystallizable fragment receptor (FcRn). Serum exposures of the generated anti-ASGR1 antibodies were analyzed in transgenic mice expressing human FcRn. Contrary to published reports of increased serum exposure of pH/Ca2+-dependent antibodies, the pH/Ca2+-dependent anti-ASGR1 antibody had rapid serum clearance in comparison to a conventional anti-ASGR1 antibody. We conducted sub-cellular trafficking studies of the anti-ASGR1 antibodies along with receptor quantification analysis for mechanistic understanding of the rapid serum clearance of pH/Ca2+-dependent anti-ASGR1 antibody. The findings from our study provide valuable insights in identifying the antigens, especially membrane bound, that may benefit from targeting with pH/Ca2+-dependent antibodies to obtain increased serum exposure.

Cellular Neonatal Fc Receptor Recycling Efficiencies can Differentiate Target-Independent Clearance Mechanisms of Monoclonal Antibodies.

In vivo clearance mechanisms of therapeutic monoclonal antibodies (mAbs) encompass both target-mediated and target-independent processes. Two distinct determinants of overall mAb clearance largely separate of target-mediated influences are non-specific cellular endocytosis and subsequent pH-dependent mAb recycling mediated by the neonatal Fc receptor (FcRn), where inter-mAb variability in the efficiency of both processes is observed. Here, we implemented a functional cell-based FcRn recycling assay via Madin-Darby canine kidney type II cells stably co-transfected with human FcRn and its light chain ß2-microglobulin. Next, a series of pH-dependent internalization studies using a model antibody demonstrated proper function of the human FcRn complex. We then applied our cellular assays to assess the contribution of both FcRn and non-specific interactions in the cellular turnover for a panel of 8 clinically relevant mAbs exhibiting variable human pharmacokinetic behavior. Our results demonstrate that the interplay of non-specific endocytosis rates, pH-dependent non-specific interactions, and engagement with FcRn all contribute to the overall recycling efficiency of therapeutic monoclonal antibodies. The predictive capacity of our assay approach was highlighted by successful identification of all mAbs within our panel possessing clearance in humans greater than 5 mL/day/kg. These results demonstrate that a combination of cell-based in vitro assays can properly resolve individual mechanisms underlying the overall in vivo recycling efficiency and non-target mediated clearance of therapeutic mAbs.

Lipid turnover through lipophagy in the newly identified extremophilic green microalga Chlamydomonas urium.

Autophagy is a central degradative pathway highly conserved among eukaryotes, including microalgae, which remains unexplored in extremophilic organisms. In this study, we described and characterized autophagy in the newly identified extremophilic green microalga Chlamydomonas urium, which was isolated from an acidic environment. The nuclear genome of C. urium was sequenced, assembled and annotated in order to identify autophagy-related genes. Transmission electron microscopy, immunoblotting, metabolomic and photosynthetic analyses were performed to investigate autophagy in this extremophilic microalga. The analysis of the C. urium genome revealed the conservation of core autophagy-related genes. We investigated the role of autophagy in C. urium by blocking autophagic flux with the vacuolar ATPase inhibitor concanamycin A. Our results indicated that inhibition of autophagic flux in this microalga resulted in a pronounced accumulation of triacylglycerols and lipid droplets (LDs). Metabolomic and photosynthetic analyses indicated that C. urium cells with impaired vacuolar function maintained an active metabolism. Such effects were not observed in the neutrophilic microalga Chlamydomonas reinhardtii. Inhibition of autophagic flux in C. urium uncovered an active recycling of LDs through lipophagy, a selective autophagy pathway for lipid turnover. This study provided the metabolic basis by which extremophilic algae are able to catabolize lipids in the vacuole.

Thioredoxin A regulates protein synthesis to maintain carbon and nitrogen partitioning in cyanobacteria.

Thioredoxins play an essential role in regulating enzyme activity in response to environmental changes, especially in photosynthetic organisms. They are crucial for metabolic regulation in cyanobacteria, but the key redox-regulated central processes remain to be determined. Physiological, metabolic, and transcriptomic characterization of a conditional mutant of the essential Synechocystis sp. PCC 6803 thioredoxin trxA gene (STXA2) revealed that decreased TrxA levels alter cell morphology and induce a dormant-like state. Furthermore, TrxA depletion in the STXA2 strain inhibited protein synthesis and led to changes in amino acid pools and nitrogen/carbon reserve polymers, accompanied by oxidation of the elongation factor-Tu. Transcriptomic analysis of TrxA depletion in STXA2 revealed a robust transcriptional response. Downregulated genes formed a large cluster directly related to photosynthesis, ATP synthesis, and CO2 fixation. In contrast, upregulated genes were grouped into different clusters related to respiratory electron transport, carotenoid biosynthesis, amino acid metabolism, and protein degradation, among others. These findings highlight the complex regulatory mechanisms that govern cyanobacterial metabolism, where TrxA acts as a critical regulator that orchestrates the transition from anabolic to maintenance metabolism and regulates carbon and nitrogen balance.

Aspectos inmunológicos en preeclampsia / Immunologic Aspects in Preeclampsia

Resumen La preeclampsia es una patología con alta morbimortalidad a nivel mundial. En esta enfermedad la placenta es un órgano de choque donde la inflamación y la respuesta inmunológica generan el daño que se traduce en el cuadro clínico característico. La tríada clásica en preeclampsia está integrada por hipertensión, edema y proteinuria, por lo que se piensa que el endotelio debe estar afectado por la actividad inflamatoria-inmunológica. El sistema inmunológico actúa en el desarrollo del embarazo y lo hace a diferentes tiempos y regulando de manera fisiológica. Tanto componentes celulares como humorales de la respuesta innata y adquirida han sido estudiados en pacientes con preeclampsia y se ha determinado que su participación es decisiva en la fisiopatología de esta enfermedad. La participación del sistema inmunológico en la fisiopatología de la preeclampsia alcanza un alto nivel de complejidad pues interacciona con otros sistemas (coagulación, renal, cardiovascular y endocrinológico entre otros) favoreciendo así la enfermedad. Es por esto que el tratamiento debe ser integral, con una visión holística del padecimiento y que requiere de un equipo multidisciplinario, que actué armónicamente para así alcanzar el mayor éxito terapéutico con la menor frecuencia de secuelas para el binomio madre-feto o madre-recién nacido. En la gestación se desarrolla la denominada "tolerancia inmunológica del embarazo", en ese estado de tolerancia inmunológica las células B y T pueden reconocer antígenos específicos (por ejemplo, los paternos) y posteriormente activarse y generar la respuesta inmunológica, por lo que la preeclampsia podría ser considerada como una patología autoinmune, donde la perdida de la tolerancia inmunológica sería la piedra angular en la fisiopatología, conocer como limitar o regular esta activación celular anómala podría servir para proponer nuevos acercamientos terapéuticos y controlar así esta enfermedad.

Abstract Preeclampsia is a pathology with high morbidity and mortality worldwide. In this disease, the placenta is an organ of shock where inflammation and the immune response generate the damage that results in the characteristic clinical scenario. The classic triad in preeclampsia is made up of hypertension, edema, and proteinuria, so it is thought that the endothelium must be affected by inflammatory-immunological activity. The immune system acts in the development of pregnancy and does so at different times and regulating physiologically. Both, cellular and humoral components of the innate and acquired response have been studied in patients with preeclampsia and it has been determined that their participation is decisive in the pathophysiology of this disease. The involvement of the immune system in the pathophysiology of preeclampsia reaches a high level of complexity since it interacts with other systems (coagulation, renal, cardiovascular and endocrinological among others) thus favoring the disease. For this reason, treatment must be comprehensive, with a holistic vision of the condition and requires a multidisciplinary team that acts harmoniously to achieve the greatest therapeutic success with the least frequency of sequelae for the mother-fetus or mother-newborn dyads. During pregnancy, the so-called "immunological tolerance of pregnancy" develops, in this state of immunological tolerance the B and T cells can recognize specific antigens (for example, the paternal ones) and later activate and generate the immune response, which is why preeclampsia could being considered an autoimmune pathology, where the loss of immunological tolerance would be the cornerstone of pathophysiology, knowing how to limit or regulate this abnormal cell activation could help to propose new therapeutic approaches and thus control this disease.

Redox-mediated activation of ATG3 promotes ATG8 lipidation and autophagy progression in Chlamydomonas reinhardtii.

Autophagy is one of the main degradative pathways used by eukaryotic organisms to eliminate useless or damaged intracellular material to maintain cellular homeostasis under stress conditions. Mounting evidence indicates a strong interplay between the generation of reactive oxygen species and the activation of autophagy. Although a tight redox regulation of autophagy has been shown in several organisms, including microalgae, the molecular mechanisms underlying this control remain poorly understood. In this study, we have performed an in-depth in vitro and in vivo redox characterization of ATG3, an E2-activating enzyme involved in ATG8 lipidation and autophagosome formation, from 2 evolutionary distant unicellular model organisms: the green microalga Chlamydomonas (Chlamydomonas reinhardtii) and the budding yeast Saccharomyces cerevisiae. Our results indicated that ATG3 activity from both organisms is subjected to redox regulation since these proteins require reducing equivalents to transfer ATG8 to the phospholipid phosphatidylethanolamine. We established the catalytic Cys of ATG3 as a redox target in algal and yeast proteins and showed that the oxidoreductase thioredoxin efficiently reduces ATG3. Moreover, in vivo studies revealed that the redox state of ATG3 from Chlamydomonas undergoes profound changes under autophagy-activating stress conditions, such as the absence of photoprotective carotenoids, the inhibition of fatty acid synthesis, or high light irradiance. Thus, our results indicate that the redox-mediated activation of ATG3 regulates ATG8 lipidation under oxidative stress conditions in this model microalga.

Redox partner interactions in the ATG8 lipidation system in microalgae.

Autophagy is a catabolic pathway that functions as a degradative and recycling process to maintain cellular homeostasis in most eukaryotic cells, including photosynthetic organisms such as microalgae. This process involves the formation of double-membrane vesicles called autophagosomes, which engulf the material to be degraded and recycled in lytic compartments. Autophagy is mediated by a set of highly conserved autophagy-related (ATG) proteins that play a fundamental role in the formation of the autophagosome. The ATG8 ubiquitin-like system catalyzes the conjugation of ATG8 to the lipid phosphatidylethanolamine, an essential reaction in the autophagy process. Several studies identified the ATG8 system and other core ATG proteins in photosynthetic eukaryotes. However, how ATG8 lipidation is driven and regulated in these organisms is not fully understood yet. A detailed analysis of representative genomes from the entire microalgal lineage revealed a high conservation of ATG proteins in these organisms with the remarkable exception of red algae, which likely lost ATG genes before diversification. Here, we examine in silico the mechanisms and dynamic interactions between different components of the ATG8 lipidation system in plants and algae. Moreover, we also discuss the role of redox post-translational modifications in the regulation of ATG proteins and the activation of autophagy in these organisms by reactive oxygen species.

Analyzing the impact of autotrophic and heterotrophic metabolism on the nutrient regulation of TOR.

The target of rapamycin (TOR) protein kinase is a master regulator of cell growth in all eukaryotes, from unicellular yeast and algae to multicellular animals and plants. Target of rapamycin balances the synthesis and degradation of proteins, lipids, carbohydrates and nucleic acids in response to nutrients, growth factors and cellular energy to promote cell growth. Among nutrients, amino acids (AAs) and glucose are central regulators of TOR activity in evolutionary distant eukaryotes such as mammals, plants and algae. However, these organisms obtain the nutrients through totally different metabolic processes. Although photosynthetic eukaryotes can use atmospheric CO2 as the sole carbon (C) source for all reactions in the cell, heterotrophic organisms get nutrients from other sources of organic C including glucose. Here, we discuss the impact of autotrophic and heterotrophic metabolism on the nutrient regulation of TOR, focusing on the role of AAs and C sources upstream of this signaling pathway.

Hemofilia adquirida A en embarazo. Caso clínico de medicina crítica en obstetricia por morbilidad extrema y su abordaje transdisciplinario perioperatorio / Acquired hemophilia A in pregnancy. Clinical case of critical medicine in obstetrics due to extreme morbidity and its perioperative transdisciplinary approach

Resumen: La identificación de múltiples factores de riesgo que predisponen a la hemorragia durante el evento obstétrico, como la hemofilia adquirida que es un trastorno que se desarrolla por la generación de autoanticuerpos inhibidores de factores de la coagulación, la interpretación objetiva de las pruebas de laboratorio rutinarias, el desarrollo de un pensamiento sistematizado en la integración diagnóstico-terapéutica por parte del personal de salud, y la disposición de los recursos farmacológicos hospitalarios, es lo que determina frecuentemente el pronóstico en pacientes obstétricas con morbilidad extrema que requieren atención multidisciplinaria en las diferentes unidades hospitalarias del sector salud de nuestro país. El objetivo es presentar un caso clínico de morbilidad extrema por hemofilia adquirida, su presentación clínica, evolución y desenlace fatal. Se presenta un caso referido de otra unidad del Sector Salud ISEM (Instituto de Salud del Estado de México), atendido en la Unidad de Cuidados Intensivos Obstétricos del Hospital «Mónica Pretelini Sáenz¼, resaltando la importancia en la integración diagnóstico-terapéutica y la interacción multifactorial de variables relacionadas con su desenlace fatal. Conclusiones: Desconocimiento de la patología, retraso en el diagnóstico, múltiples procedimientos condicionantes de hemorragia iatrógena y la limitación en recursos terapéuticos son factores que contribuyen a un desenlace fatal.

Abstract: The identification of multiple risk factors that predispose to bleeding during the obstetric event, such as acquired hemophilia, which is a disorder that develops due to the generation of autoantibodies that inhibit coagulation factors, the objective interpretation of routine laboratory tests , the development of systematized thinking in diagnostic-therapeutic integration by health personnel, and the provision of hospital pharmacological resources, is what frequently determines the prognosis in obstetric patients with extreme morbidity who require multidisciplinary care in the different hospital units of the health sector of our country. The objective is to present a clinical case of extreme morbidity due to acquired hemophilia, its clinical presentation, evolution and fatal outcome. A case referred from another unit of the ISEM (Instituto de Salud del Estado de México) Health Sector, treated at the Obstetric Intensive Care Unit of the «Mónica Pretelini Sáenz¼ Hospital, is presented, highlighting the importance of diagnostic-therapeutic integration, and the multifactorial interaction of variables related to its fatal outcome. Conclusions: Ignorance of the pathology, delay in diagnosis, multiple conditioning procedures of iatrogenic hemorrhage and the limitation in therapeutic resources are factors that contribute to a fatal outcome.

Deciphering the function and evolution of the target of rapamycin signaling pathway in microalgae.

Microalgae constitute a highly diverse group of photosynthetic microorganisms that are widely distributed on Earth. The rich diversity of microalgae arose from endosymbiotic events that took place early in the evolution of eukaryotes and gave rise to multiple lineages including green algae, the ancestors of land plants. In addition to their fundamental role as the primary source of marine and freshwater food chains, microalgae are essential producers of oxygen on the planet and a major biotechnological target for sustainable biofuel production and CO2 mitigation. Microalgae integrate light and nutrient signals to regulate cell growth. Recent studies identified the target of rapamycin (TOR) kinase as a central regulator of cell growth and a nutrient sensor in microalgae. TOR promotes protein synthesis and regulates processes that are induced under nutrient stress such as autophagy and the accumulation of triacylglycerol and starch. A detailed analysis of representative genomes from the entire microalgal lineage revealed that the highly conserved central components of the TOR pathway are likely to have been present in the last eukaryotic common ancestor, and the loss of specific TOR signaling elements at an early stage in the evolution of microalgae. Here we examine the evolutionary conservation of TOR signaling components in diverse microalgae and discuss recent progress of this signaling pathway in these organisms.

Characterization and impact of sunflower plastidial octanoyltransferases (Helianthus annuus L.) on oil composition.

Prosthetic lipoyl groups are essential for the metabolic activity of several multienzyme complexes in most organisms. In plants, octanoyltransferase (LIP2) and lipoyl synthase (LIP1) enzymes in the mitochondria and plastids participate in the de novo synthesis of lipoic acid, and in the attachment of the lipoyl cofactors to their specific targets. In plastids, the lipoylated pyruvate dehydrogenase complex catalyzes the synthesis of the acetyl-CoA that is required for de novo fatty acid synthesis. Since lipoic acid transport across plastid membranes has not been demonstrated, these organelles require specific plastidial LIP1 and LIP2 activities for the in situ synthesis of this cofactor. Previously, one essential LIP1 enzyme and two redundant LIP2 enzymes have been identified within Arabidopsis chloroplasts. In this study, two plastidial sunflower (Helianthus annuus L.) LIP2 genes (HaLIP2p1 and HaLIP2p2) were identified, cloned and characterized. The expression of these genes in different tissues was studied and the tertiary structure of the peptides they encode was modeled by protein docking. These genes were overexpressed in Escherichia coli and their impact on bacterial fatty acid synthesis was studied. Finally, transgenic Arabidopsis plants overexpressing HaLIP2p1 were generated and their seed lipid profiles analyzed. The lipid composition of the transgenic seeds, particularly their TAG species, differed from that of wild-type plants, revealing a relationship between lipoic acid synthesis and the accumulation of storage lipids in Arabidopsis seeds.

Exploring the Diversity of the Thioredoxin Systems in Cyanobacteria.

Cyanobacteria evolved the ability to perform oxygenic photosynthesis using light energy to reduce CO2 from electrons extracted from water and form nutrients. These organisms also developed light-dependent redox regulation through the Trx system, formed by thioredoxins (Trxs) and thioredoxin reductases (TRs). Trxs are thiol-disulfide oxidoreductases that serve as reducing substrates for target enzymes involved in numerous processes such as photosynthetic CO2 fixation and stress responses. We focus on the evolutionary diversity of Trx systems in cyanobacteria and discuss their phylogenetic relationships. The study shows that most cyanobacteria contain at least one copy of each identified Trx, and TrxA is the only one present in all genomes analyzed. Ferredoxin thioredoxin reductase (FTR) is present in all groups except Gloeobacter and Prochlorococcus, where there is a ferredoxin flavin-thioredoxin reductase (FFTR). Our data suggest that both TRs may have coexisted in ancestral cyanobacteria together with other evolutionarily related proteins such as NTRC or DDOR, probably used against oxidative stress. Phylogenetic studies indicate that they have different evolutionary histories. As cyanobacteria diversified to occupy new habitats, some of these proteins were gradually lost in some groups. Finally, we also review the physiological relevance of redox regulation in cyanobacteria through the study of target enzymes.

Photosynthetic assimilation of CO2 regulates TOR activity.

The target of rapamycin (TOR) kinase is a master regulator that integrates nutrient signals to promote cell growth in all eukaryotes. It is well established that amino acids and glucose are major regulators of TOR signaling in yeast and metazoan, but whether and how TOR responds to carbon availability in photosynthetic organisms is less understood. In this study, we showed that photosynthetic assimilation of CO2 by the Calvin-Benson-Bassham (CBB) cycle regulates TOR activity in the model single-celled microalga Chlamydomonas reinhardtii Stimulation of CO2 fixation boosted TOR activity, whereas inhibition of the CBB cycle and photosynthesis down-regulated TOR. We uncovered a tight link between TOR activity and the endogenous level of a set of amino acids including Ala, Glu, Gln, Leu, and Val through the modulation of CO2 fixation and the use of amino acid synthesis inhibitors. Moreover, the finding that the Chlamydomonas starch-deficient mutant sta6 displayed disproportionate TOR activity and high levels of most amino acids, particularly Gln, further connected carbon assimilation and amino acids to TOR signaling. Thus, our results showed that CO2 fixation regulates TOR signaling, likely through the synthesis of key amino acids.

Dark side of cyanobacteria: searching for strategies to control blooms.

Cyanobacteria are ecologically one of the most prolific groups of photosynthetic prokaryotes in marine and freshwater habitats. They are primary producer microorganisms and are involved in the production of important secondary metabolites, including toxic compounds such as cyanotoxins. Environmental conditions promote massive growth of these microbes, causing blooms that can have critical ecological and public health implications. In this highlight, we discuss some of the approaches being addressed to prevent these blooms, such as control of nutrient loading, treatments to minimize growth or monitoring interactions with other species.

Depletion of m-type thioredoxin impairs photosynthesis, carbon fixation, and oxidative stress in cyanobacteria.

Thioredoxins (Trxs) are disulfide oxidoreductases that regulate many biological processes. The m-type thioredoxin (TrxA) is the only Trx present in all oxygenic photosynthetic organisms. Extensive biochemical and proteomic analyses have identified many TrxA target proteins in different photosynthetic organisms. However, the precise function of this essential protein in vivo is still poorly known. In this study, we generated a conditional Synechocystis sp. PCC 6803 mutant strain (STXA2) using an on-off promoter that is able to survive with only 2% of the TrxA level of the wild-type (WT) strain. STXA2 characterization revealed that TrxA depletion results in growth arrest and pronounced impairment of photosynthesis and the Calvin-Benson-Bassham (CBB) cycle. Analysis of the in vivo redox state of the bifunctional enzyme fructose-1,6-bisphosphatase/sedoheptulose-1,7-bisphosphatase showed higher levels of oxidation that affected enzyme activity in STXA2. This result implies that TrxA-mediated redox regulation of the CBB cycle is conserved in both cyanobacteria and chloroplasts, although the targets have different evolutionary origins. The STXA2 strain also accumulated more reactive oxygen species and was more sensitive to oxidative stress than the WT. Analysis of the in vivo redox state of 2-Cys peroxiredoxin revealed full oxidation, corresponding with TrxA depletion. Overall, these results indicate that depletion of TrxA in STXA2 greatly alters the cellular redox state, interfering with essential processes such as photosynthetic machinery operativity, carbon assimilation, and oxidative stress response. The TrxA regulatory role appears to be conserved along the evolution of oxygenic photosynthetic organisms.

Estrategias para empoderar a las mujeres en relación con los derechos reproductivos y la planificación familiar: revisión sistemática desde las corrientes bioéticas / Strategies to empower women in relation to reproductive rights and family planning: a systematic review from bioethical currents / Estratégias para empoderar as mulheres em relação aos direitos reprodutivo e de planejamento familiar: revisão sistemática desde las correntes bioéticas

Resumen El presente artículo informa de una investigación cuyo objetivo fue definir las estrategias para empoderar a las mujeres mexicanas en sus decisiones de planificación familiar y de establecer compromisos y responsabilidades con sus parejas. Se realizó una revisión sistemática, incluyendo PubMed, Redalyc y Scopus, y se incluyeron diez artículos originales de dos continentes y diversas poblaciones. De los estudios realizados en México y Latinoamérica ninguno proporcionó una propuesta para implementar mejoras en la adopción de un método de planificación familiar entre las mujeres que viven violencia de pareja. Se concluye que la capacitación y formación bioética del personal de salud puede abonar a lograr que el proceso de información y decisión por parte de la mujer o de la pareja sean llevados a cabo con apego a la bioética, buscando el beneficio individual y protección del bienestar de la mujer y, por ende, de su familia.

Abstract This article reports on research aimed at defining strategies to empower Mexican women in their family planning decisions and to establish commitments and responsibilities with their partners. A systematic review was conducted, including PubMed, Redalyc and Scopus, and ten original articles from two continents and diverse populations were included. Of the studies conducted in Mexico and Latin America, none provided a proposal to implement improvements in the adoption of a family planning method among women who experience intimate partner violence. It is concluded that bioethical training and education of health personnel can contribute to ensure that the information and decision-making process by the woman or the couple is carried out in accordance with bioethics, seeking individual benefit and protection of the wellbeing of the woman and, therefore, of her family.

Resumo O presente artigo informa sobre uma pesquisa cujo objetivo foi definir as estratégias para empoderar as mulheres mexicanas em suas decisões de planejamento familiar e de estabelecer compromissos e responsabilidades com seus companheiros. Foi realizada uma revisão sistemática, incluindo PubMed, Redalyc e Scopus, e se incluíram dez artigos originais de dois continentes e diversas populações. Dos estudos realizados no México e na América Latina nenhum proporcionou uma proposta para implementar melhorias na adoção de um método de planejamento familiar entre as mulheres que sofrem violência conjugal. Conclui-se que a capacitação e formação bioética do pessoal de saúde pode lograr alcançar que o processo de informação e decisão por parte da mulher ou do casal sejam levados a cabo com apego à bioética, buscando o beneficio individual e a proteção do bem estar da mulher e, por conseguinte, de sua família.

Impact of sunflower (Helianthus annuus L.) plastidial lipoyl synthases genes expression in glycerolipids composition of transgenic Arabidopsis plants.

Lipoyl synthases are key enzymes in lipoic acid biosynthesis, a co-factor of several enzyme complexes involved in central metabolism. Plant pyruvate dehydrogenase complex (PDH), located in mitochondria and plastids, catalyses the first step of fatty acid biosynthesis in these organelles. Among their different components, the E2 subunit requires the lipoic acid prosthetic group to be active. De novo lipoic acid biosynthesis is achieved by the successive action of two enzymes on octanoyl-ACP: octanoyltransferase (LIP2) and lipoyl synthase (LIP1). In this study, two plastidial lipoyl synthase genes from sunflower (Helianthus annuus L.) were identified (HaLIP1p1 and HaLIP1p2), sequenced and cloned in a heterologous production system (Escherichia coli). Gene expression studies revealed similar expression patterns for both isoforms, with a slight predominance of HaLIP1p1 in vegetative tissues and mature seeds. Tertiary structural models for these enzymes indicate they both have the same theoretical catalytic sites, using lipoyl-lys and 5-deoxyadenosine as docking substrates. The fatty acid profile of E. coli cells overexpressing HaLIP1p1 and HaLIP1p2 did not present major differences, and the in vivo activity of both proteins was confirmed by complementation of an E. coli JW0623 mutant in which lipoyl synthase is defective. Although no significant differences were detected in the total fatty acid composition of transgenic Arabidopsis thaliana seeds overexpressing any of both proteins, a lipidomic analysis revealed a redistribution of the glycerolipid species, accompanied with increased phosphatidylethanolamine (PE) content and a decrease in diacyglycerols (DAG) and phosphatidylcholine (PC). Depletion of the SAM co-factor caused by HaLIP1p1 and HaLIP1p2 overexpression in transgenic plants could explain this remodelling through its effects on PC synthesis.

Morbilidad extrema (near-miss) en obstetricia. Revisión de la literatura / Severe morbidity (near-miss) in obstetrics. Literature review

Resumen: Objetivo: Presentar la evidencia científica más reciente referente a la definición, diagnóstico y consecuencias de morbilidad extrema en obstetricia (MEO). Metodología de búsqueda: Búsqueda en PubMed, The Cochrane Library, OVID, Science Direct, Google Académico, Artemisa, LILACS e Imbiomed de artículos publicados en inglés y español entre los años 2005 a 2018 con las siguientes palabras clave: severe maternal morbidity, near miss morbidity, severe acute maternal morbidity, obstetric near miss and maternal near miss. Se excluyeron estudios cualitativos. Resultados: La MEO (o near miss) se refiere a cualquier complicación aguda que puede presentarse en el embarazo, labor o hasta seis semanas después de haber concluido el embarazo, estas complicaciones ponen en riesgo la vida de la madre, pero no resulta en su muerte. Los indicadores de MEO fueron desarrollados con base a la incidencia y presencia de trastornos hemorrágicos, hipertensivos y otras alteraciones sistémicas y condiciones maternas graves que pueden tener un impacto en la salud de la madre. En la actualidad, se sugiere que el estudio de los indicadores de MEO son de más utilidad que los de muerte materna. Conclusiones: El ejercicio de la práctica médica con base en la mejor evidencia científica, el estudio y la mejora de la calidad de la práctica clínica, de la planificación familiar, la asesoría prenatal y los programas hospitalarios son estrategias que permitirán ayudar a disminuir los casos de MEO.

Abstract. Objective: To provide the most recent scientific evidence about definitions, diagnosis and consequences of severe maternal morbidity (SMM). Research methodology: We searched databases in PubMed, The Cochrane Library, OVID, Science Direct, Google Scholar, Artemisa, LILACS and Imbiomed from 2005 to 2018 with the following keywords: severe maternal morbidity, near miss morbidity, severe acute maternal morbidity, obstetric near miss and maternal near miss. The search was restricted to articles written in the English and Spanish language and published from 2005 to 2018. Qualitative studies were excluded. Results: SMM or maternal near miss event refers to any acute obstetric complication that immediately threatens a woman's survival but does not result in her death either by chance or because of hospital care she receives during pregnancy, labor or within six weeks of termination of pregnancy. The indicators for SMM were developed and based on the incidence and presence of hemorrhagic disorders, hypertensive disorders, other systemic disorders and severe maternal conditions which could have an impact on maternal health. Nowadays it is suggested that the study of indicators for SMM is a more useful indicator of obstetric care than mortality. Conclusions: Use of best evidence-based practices, studying and improving the effectiveness and quality of clinical practice, family planning, prenatal check-up, and hospital obstetric care programs are strategies that could help to reduce cases of SMM.

Lethality caused by ADP-glucose accumulation is suppressed by salt-induced carbon flux redirection in cyanobacteria.

Cyanobacteria are widely distributed photosynthetic organisms. During the day they store carbon, mainly as glycogen, to provide the energy and carbon source they require for maintenance during the night. Here, we generate a mutant strain of the freshwater cyanobacterium Synechocystis sp. PCC 6803 lacking both glycogen synthases. This mutant has a lethal phenotype due to massive accumulation of ADP-glucose, the substrate of glycogen synthases. This accumulation leads to alterations in its photosynthetic capacity and a dramatic decrease in the adenylate energy charge of the cell to values as low as 0.1. Lack of ADP-glucose pyrophosphorylase, the enzyme responsible for ADP-glucose synthesis, or reintroduction of any of the glycogen synthases abolishes the lethal phenotype. Viability of the glycogen synthase mutant is also fully recovered in NaCl-supplemented medium, which redirects the surplus of ADP-glucose to synthesize the osmolite glucosylglycerol. This alternative metabolic sink also suppresses phenotypes associated with the defective response to nitrogen deprivation characteristic of glycogen-less mutants, restoring the capacity to degrade phycobiliproteins. Thus, our system is an excellent example of how inadequate management of the adenine nucleotide pools results in a lethal phenotype, and the influence of metabolic carbon flux in cell viability and fitness.