38 research outputs found

    Adaptive Evolution of Phosphorus Metabolism in Prochlorococcus.

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    Inorganic phosphorus is scarce in the eastern Mediterranean Sea, where the high-light-adapted ecotype HLI of the marine picocyanobacterium Prochlorococcus marinus thrives. Physiological and regulatory control of phosphorus acquisition and partitioning has been observed in HLI both in culture and in the field; however, the optimization of phosphorus metabolism and associated gains for its phosphorus-limited-growth (PLG) phenotype have not been studied. Here, we reconstructed a genome-scale metabolic network of the HLI axenic strain MED4 (iJC568), consisting of 568 metabolic genes in relation to 794 reactions involving 680 metabolites distributed in 6 subcellular locations. iJC568 was used to quantify metabolic fluxes under PLG conditions, and we observed a close correspondence between experimental and computed fluxes. We found that MED4 has minimized its dependence on intracellular phosphate, not only through drastic depletion of phosphorus-containing biomass components but also through network-wide reductions in phosphate-reaction participation and the loss of a key enzyme, succinate dehydrogenase. These alterations occur despite the stringency of having relatively few pathway redundancies and an extremely high proportion of essential metabolic genes (47%; defined as the percentage of lethal in silico gene knockouts). These strategies are examples of nutrient-controlled adaptive evolution and confer a dramatic growth rate advantage to MED4 in phosphorus-limited regions. IMPORTANCE Microbes are known to employ three basic strategies to compete for limiting elemental resources: (i) cell quotas may be adjusted by alterations to cell physiology or by substitution of a more plentiful resource, (ii) stressed cells may synthesize high-affinity transporters, and (iii) cells may access more costly sources from internal stores, by degradation, or by petitioning other microbes. In the case of phosphorus, a limiting resource in vast oceanic regions, the cosmopolitan cyanobacterium Prochlorococcus marinus thrives by adopting all three strategies and a fourth, previously unknown strategy. By generating a detailed model of its metabolism, we found that strain MED4 has evolved a way to reduce its dependence on phosphate by minimizing the number of enzymes involved in phosphate transformations, despite the stringency of nearly half of its metabolic genes being essential for survival. Relieving phosphorus limitation, both physiologically and throughout intermediate metabolism, substantially improves phosphorus-specific growth rates

    Dudawalamides A−D, Antiparasitic Cyclic Depsipeptides from the Marine Cyanobacterium Moorea producens

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    HPLC. DudA family of 2,2-dimethyl-3-hydroxy-7-octynoic acid (Dhoya)-containing cyclic depsipeptides, named dudawalamides A−D (1−4), was isolated from a Papua New Guinean field collection of the cyanobacterium Moorea producens using bioassay-guided and spectroscopic approaches. The planar structures of dudawalamides A−D were determined by a combination of 1D and 2D NMR experiments and MS analysis, whereas the absolute configurations were determined by X-ray crystallography, modified Marfey’s analysis, chiral-phase GCMS, and chiral-phase awalamides A−D possess a broad spectrum of antiparasitic activity with minimal mammalian cell cytotoxicity. Comparative analysis of the Dhoya-containing class of lipopeptides reveals intriguing structure−activity relationship features of these NRPS−PKS-derived metabolites and their derivatives.HPLC. DudA family of 2,2-dimethyl-3-hydroxy-7-octynoic acid (Dhoya)-containing cyclic depsipeptides, named dudawalamides A−D (1−4), was isolated from a Papua New Guinean field collection of the cyanobacterium Moorea producens using bioassay-guided and spectroscopic approaches. The planar structures of dudawalamides A−D were determined by a combination of 1D and 2D NMR experiments and MS analysis, whereas the absolute configurations were determined by X-ray crystallography, modified Marfey’s analysis, chiral-phase GCMS, and chiral-phase awalamides A−D possess a broad spectrum of antiparasitic activity with minimal mammalian cell cytotoxicity. Comparative analysis of the Dhoya-containing class of lipopeptides reveals intriguing structure−activity relationship features of these NRPS−PKS-derived metabolites and their derivatives

    19-Hydroxy-bufalin, a major bufadienolide isolated from the parotoid gland secretions of the Panamanian endemic toad Rhinella centralis (Bufonidae), inhibits the growth of Trypanosoma cruzi

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    American trypanosomiasis is a parasitic neglected disease, responsible for the death of approximately 10,000 people every year. Amphibians are recognized for producing in their cutaneous glands substances with pharmacological potential against a variety of pathologies. Here we investigated the antiprotozoal activity against Trypanosoma cruzi of bufadienolides isolated from the parotoid glands secretions of the toad Rhinella centralis from Panama. NMR and mass spectrometry analysis led to the identification of the active compound 19-hydroxybufalin, for which its antitrypanosomal activity and occurrence in the genus Rhinella are reported for the first time. This compound showed low cytotoxicity and significant selectivity which confers to it a potential role for the treatment of Chagas diseaseAmerican trypanosomiasis is a parasitic neglected disease, responsible for the death of approximately 10,000 people every year. Amphibians are recognized for producing in their cutaneous glands substances with pharmacological potential against a variety of pathologies. Here we investigated the antiprotozoal activity against Trypanosoma cruzi of bufadienolides isolated from the parotoid glands secretions of the toad Rhinella centralis from Panama. NMR and mass spectrometry analysis led to the identification of the active compound 19-hydroxybufalin, for which its antitrypanosomal activity and occurrence in the genus Rhinella are reported for the first time. This compound showed low cytotoxicity and significant selectivity which confers to it a potential role for the treatment of Chagas diseas

    Estudio de pre-factibilidad de una micro planta de aceite de palta en el distrito de San Juan de Lurigancho año 2019

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    La investigación es fundamental en la formación académica, desarrollándose la tesis: “Estudio de Pre-factibilidad de una micro planta de aceite de palta en el distrito de San Juan de Lurigancho, 2019” cuyo objetivo general, es conocer el proceso de fabricacion del aceite de palta, sus propiedades para su posterior implementación bajo un proyecto ejecutador. En el desarrollo de la investigación el método fue cuantitativo, diseño descriptivo y aplicado. De estudio descriptivo con incidencia en la parte teórica, así como procedimientos de elaboración del aceite de palta. Tomando el método de prensado en frío siendo el más práctico y económico (Condori Cahui, 2016). Se presenta la secuencia del proceso (diagrama de flujo), las máquinas y herramientas del proceso, y los indicadores referenciales de propiedades físicas y químicas del producto bajo parámetros teóricos y prácticos de otros estudios ya ejecutados internacional y nacionalmente. Con capacidad máxima 1200 botellas/año y un mínimo es el punto de equilibrio de 600 botellas/ año y la implementación de la micro planta de aceite de palta requiere una inversión de S/. 140,000, las ratios obtenidas VANE y VANF son S/. 12,000 y S/. 8,000 respectivamente

    Multi-Species Transcriptome Assemblies of Cultivated and Wild Lentils (Lens sp.) Provide a First Glimpse at the Lentil Pangenome

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    [EN] Lentils (Lens sp.) are one of the main sources of protein for humans in many regions, in part because their rusticity allows them to withstand semi-dry climates and tolerate a wide spectrum of pests. Both are also highly sought-after attributes to face climate change. Wild accessions, rather than cultivated varieties, are typically the holders of most influential alleles for rusticity traits. However, most genomic and transcriptomic research conducted in lentils has been carried out on commercial accessions (L. culinaris), while wild relatives have been largely neglected. Herein, we assembled, annotated, and evaluated the transcriptomes of eight lentil accessions, including the cultivated Lens culinaris and the wild relatives: L. orientalis, L. tomentosus, L. ervoides, L. lamottei, L. nigricans, and two L. odemensis. The assemblies allowed, for the first time, a comparison among different lentil taxa at the coding sequence level, providing further insights into the evolutionary relationships between cultivated and wild germplasm and suggesting a grouping of the seven accessions into at least three conceivable gene pools. Moreover, orthologous clustering allowed a first estimation of the lentil pan-transcriptome. It is composed of 15,910 core genes, encoded in all accessions, and 24,226 accessory genes. The different pan-transcriptome clusters were also screened for Pfam-domain enrichment. The present study has a high novelty, as it is the first pan-transcriptome analysis using six wild species in addition to cultivated species. Because of the amount of transcript sequences provided, our findings will greatly boost lentil research and assist breeding efforts.S

    Pre-Columbian alloys from the royal tombs of Sipán and from the Museum of Sicán

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    On the north coast of present-day Peru, approximately between 50 and 700 AD, flourished the Moche civilization. It was an advanced culture, and the Moche were sophisticated metalsmiths. The Moche metal working ability was impressively shown by the excavations of the “Tumbas Reales de Sipán”, discovered by W. Alva and co-workers in 1987. The Sicán culture is a successive civilization (750-1375 AD) which extended as far as present day Piura in the north and Trujillo in the south. The Sicán culture was strongly influenced by the Moche culture, particularly in its metallurgical development (Shimada and Griffin, 1994). The metal objects from the Museums of Sipán and Sicán were analyzed with a portable equipment which uses energy-dispersive X-ray fluorescence (XRF). This portable equipment is composed of a small size X-ray tube and a Si-PIN thermoelectrically cooled X-ray detector. It was determined that the analyzed artefacts are composed of gold, silver and copper alloys, of gilded copper, of silvered gold, and of tumbaga, the last being a poor gold alloy enriched at the surface by depletion gilding, i.e. removing copper from the surface. In the case of gold, silver and copper alloys, their composition was determined by EDXRF analysis employing standard alloys. In the case of gilded copper, silvered copper and of tumbaga, the ratio Cu(Ka/Kb) was accurately determined from the X-ray spectra, first in order to clearly distinguish them, and subsequently in order to determine the thickness of the gilding. Mean values of 0.4 µm and 2.7 µm were determined for gilded copper and tumbaga, respectively. For gilded silver, the ratio Ag(Ka /Kb) was measured. The ratios Au-Ka/Cu-Ka, Ag-Ka/Cu-Ka and Au-Ka/Ag-Ka (gilded copper, silvered copper, and gilded silver, respectively) also depend on the thickness of gilding or silvering, and were employed to this aim.Sur la côte nord de l’actuel Pérou, entre environ 50 et 700 AD, prospérait la civilisation Moche. Cette culture était très avancée et les Moches étaient des métallurgistes avertis. Leur talent pour travailler le métal est illustré par les fouilles du site des “Tumbas Reales de Sipán”, découvert par W. Alva et collaborateurs en 1987. La culture Sicán est une civilisation qui se succède de 750 à 1375 AD et qui s’étend au nord jusqu’à Piura et au sud jusqu’à Trujillo. La culture Sicán a été fortement influencée par la culture Moche, et tout particulièrement leur métallurgie (Shimada et Griffin, 1994). Les objets métalliques des musées de Sipán et Sicán ont été analysés avec un spectromètre portable à fluorescence X à dispersion d’énergie. Cet équipement est constitué d’un tube à rayons-X miniaturisé et d’un détecteur de rayons-X de type Si-PIN à refroidissement thermoélectrique.  Nous avons pu montrer que les objets sont fabriqués avec des alliages d’or, argent et cuivre, avec du cuivre et de l’argent doré ainsi qu’avec du tumbaga, alliage d’or enrichi par mise en couleur, c’est-à-dire par appauvrissement en surface du cuivre. Les compositions des alliages en or, argent et cuivre ont été déterminées par ED-FX au moyen de standards d’or. Pour différencier les cuivres et les argents dorés ainsi que les tumbaga et ensuite déterminer l’épaisseur de la dorure, le rapport Cu(Ka/Kb) a été déterminé avec précision à partir des spectres à rayons X. Des valeurs moyennes de, respectivement, 0,4µm et 2,7µm ont été déterminées pour les cuivres dorés et les tumbaga. Pour les argents dorés, c’est le rapport Ag(Ka/Kb) qui a été mesuré. Les rapports Au-Ka/Cu-Ka, Ag-Ka/Cu-Ka et Au-Ka/Ag-Ka (cuivres dorés, cuivres argentés et argents dorés, respectivement) dépendent aussi de l’épaisseur de la dorure et de l’argenture

    I Diretriz brasileira de cardio-oncologia pediátrica da Sociedade Brasileira de Cardiologia

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    Sociedade Brasileira de Oncologia PediátricaUniversidade Federal de São Paulo (UNIFESP) Instituto de Oncologia Pediátrica GRAACCUniversidade Federal de São Paulo (UNIFESP)Universidade de São Paulo Faculdade de Medicina Instituto do Coração do Hospital das ClínicasUniversidade Federal do Rio Grande do Sul Hospital de Clínicas de Porto AlegreInstituto Materno-Infantil de PernambucoHospital de Base de BrasíliaUniversidade de Pernambuco Hospital Universitário Oswaldo CruzHospital A.C. CamargoHospital do CoraçãoSociedade Brasileira de Cardiologia Departamento de Cardiopatias Congênitas e Cardiologia PediátricaInstituto Nacional de CâncerHospital Pequeno PríncipeSanta Casa de Misericórdia de São PauloInstituto do Câncer do Estado de São PauloUniversidade Federal de São Paulo (UNIFESP) Departamento de PatologiaHospital Infantil Joana de GusmãoUNIFESP, Instituto de Oncologia Pediátrica GRAACCUNIFESP, Depto. de PatologiaSciEL

    The relationship between genetic liability, childhood maltreatment, and IQ: findings from the EU-GEI multicentric case–control study

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    This study investigated if the association between childhood maltreatment and cognition among psychosis patients and community controls was partially accounted for by genetic liability for psychosis. Patients with first-episode psychosis (N = 755) and unaffected controls (N = 1219) from the EU-GEI study were assessed for childhood maltreatment, intelligence quotient (IQ), family history of psychosis (FH), and polygenic risk score for schizophrenia (SZ-PRS). Controlling for FH and SZ-PRS did not attenuate the association between childhood maltreatment and IQ in cases or controls. Findings suggest that these expressions of genetic liability cannot account for the lower levels of cognition found among adults maltreated in childhood
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