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Flavobacterium columnare causes columnaris disease in fish. Columnaris disease is incompletely understood, and adequate control measures are lacking. The type IX secretion system (T9SS) is required for F. columnare gliding motility and virulence. The T9SS and gliding motility machineries share some, but not all, components. GldN (required for gliding and for secretion) and PorV (involved in secretion but not required for gliding) are both needed for virulence, implicating T9SS-mediated secretion in virulence. The role of motility in virulence is uncertain. We constructed and analyzed sprB, sprF, and gldJ mutants that were defective for motility but that maintained T9SS function to understand the role of motility in virulence. Wild-type cells moved rapidly and formed spreading colonies. In contrast, sprB and sprF deletion mutants were partially defective in gliding and formed nonspreading colonies. Both mutants exhibited reduced virulence in rainbow trout fry. A gldJ deletion mutant was nonmotile, secretion deficient, and avirulent in rainbow trout fry. To separate the roles of GldJ in secretion and in motility, we generated gldJ truncation mutants that produce nearly full-length GldJ. Mutant gldJ563, which produces GldJ truncated at amino acid 563, was defective for gliding but was competent for secretion as measured by extracellular proteolytic activity. This mutant displayed reduced virulence in rainbow trout fry, suggesting that motility contributes to virulence. Fish that survived exposure to the sprB deletion mutant or the gldJ563 mutant exhibited partial resistance to later challenge with wild-type cells. The results aid our understanding of columnaris disease and may suggest control strategies.IMPORTANCEFlavobacterium columnare causes columnaris disease in many species of freshwater fish in the wild and in aquaculture systems. Fish mortalities resulting from columnaris disease are a major problem for aquaculture. F. columnare virulence is incompletely understood, and control measures are inadequate. Gliding motility and protein secretion have been suggested to contribute to columnaris disease, but evidence directly linking motility to disease was lacking. We isolated and analyzed mutants that were competent for secretion but defective for motility. Some of these mutants exhibited decreased virulence. Fish that had been exposed to these mutants were partially protected from later exposure to the wild type. The results contribute to our understanding of columnaris disease and may aid development of control strategies.
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Proteínas Bacterianas , Enfermedades de los Peces , Animales , Proteínas Bacterianas/metabolismo , Virulencia , Proteínas Motoras Moleculares/metabolismo , Flavobacterium , Enfermedades de los Peces/microbiologíaRESUMEN
OBJECTIVE: To share our experience with belimumab in lupus pregnant women and to review the relevant published literature on its use in this scenario. METHODS: A prospective observational study of pregnant patients with lupus was conducted. Additionally, MEDLINE and EMBASE databases were searched, and a secondary hand search of the literature was performed. Studies were evaluated and visualised descriptively. RESULTS: Sixteen pregnancies of 12 lupus women were included, six (involving eight pregnancies) received belimumab throughout their illness, five of them during some period of gestation. In this group, there was one miscarriage, one elective termination and seven live foetuses (including two live twins). There was one type I intrauterine growth retardation, and a preterm pregnancy due to premature rupture of membranes (PPROM). One mild lupus flare was detected. There were no cases of pre-eclampsia, gestational diabetes mellitus or hypertension. All neonates had normal Apgar scores at birth, none needed critical care. There were no congenital anomalies. After the search, we identified 10 case reports and case series, and five registries. Among the 39 reported cases (41 pregnancies), there were 5 PPROM, 4 pre-eclampsia, and 1 eclampsia. All women made full recoveries. Nineteen new-borns had low birth weight. There were no malformations. While registries did not indicate an increased risk of birth defects or pregnancy loss, there was a higher risk of neonatal infections. CONCLUSIONS: Belimumab may be an option for pregnant women with difficult-to-control lupus. Further research is needed to confirm the absence of association between belimumab and foetal harm.
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Anticuerpos Monoclonales Humanizados , Inmunosupresores , Lupus Eritematoso Sistémico , Complicaciones del Embarazo , Resultado del Embarazo , Humanos , Embarazo , Femenino , Anticuerpos Monoclonales Humanizados/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Estudios Prospectivos , Adulto , Complicaciones del Embarazo/tratamiento farmacológico , Inmunosupresores/uso terapéutico , Inmunosupresores/efectos adversos , Recién Nacido , Aborto Espontáneo/epidemiología , Adulto JovenRESUMEN
The application of protein hydrolysates (PH) biostimulants is considered a promising approach to promote crop growth and resilience against abiotic stresses. Nevertheless, PHs bioactivity depends on both the raw material used for their preparation and the molecular fraction applied. The present research aimed at investigating the molecular mechanisms triggered by applying a PH and its fractions on plants subjected to nitrogen limitations. To this objective, an integrated transcriptomic-metabolomic approach was used to assess lettuce plants grown under different nitrogen levels and treated with either the commercial PH Vegamin® or its molecular fractions PH1(>10 kDa), PH2 (1-10 kDa) and PH3 (<1 kDa). Regardless of nitrogen provision, biostimulant application enhanced lettuce biomass, likely through a hormone-like activity. This was confirmed by the modulation of genes involved in auxin and cytokinin synthesis, mirrored by an increase in the metabolic levels of these hormones. Consistently, PH and PH3 upregulated genes involved in cell wall growth and plasticity. Furthermore, the accumulation of specific metabolites suggested the activation of a multifaceted antioxidant machinery. Notwithstanding, the modulation of stress-response transcription factors and genes involved in detoxification processes was observed. The coordinated action of these molecular entities might underpin the increased resilience of lettuce plants against nitrogen-limiting conditions. In conclusion, integrating omics techniques allowed the elucidation of mechanistic aspects underlying PH bioactivity in crops. Most importantly, the comparison of PH with its fraction PH3 showed that, except for a few peculiarities, the effects induced were equivalent, suggesting that the highest bioactivity was ascribable to the lightest molecular fraction.
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Lactuca , Nitrógeno , Hidrolisados de Proteína , Lactuca/metabolismo , Lactuca/genética , Lactuca/efectos de los fármacos , Lactuca/crecimiento & desarrollo , Nitrógeno/metabolismo , Hidrolisados de Proteína/metabolismo , Hidrolisados de Proteína/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Metabolómica , Reguladores del Crecimiento de las Plantas/metabolismo , Transcriptoma/genética , MultiómicaRESUMEN
Bone and joint infections (BJIs) are difficult to treat and affect a growing number of patients, in which relapses are observed in 10-20% of the case. These relapses, which call for prolonged antibiotic treatment and increase resistance emergence risk, may originate from ill understood adaptation of the pathogen to the host. Here, we investigated three pairs of Escherichia coli strains from BJI cases and their relapses to unravel in-patient adaptation. Whole genome comparison presented evidence for positive selection and phenotypic characterization showed that biofilm formation remained unchanged, contrary to what is usually described in such cases. Although virulence was not modified, we identified the loss of two virulence factors contributing to immune system evasion in one of the studied strains. Other strategies, including global growth optimization and colicin production, likely allowed the strains to outcompete competitors. This work highlights the variety of strategies allowing in-patient adaptation in BJIs.
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The health and environmental risks associated with antibiotic use in aquaculture have promoted bacterial probiotics as an alternative approach to control fish infections in vulnerable larval and juvenile stages. However, evidence-based identification of probiotics is often hindered by the complexity of bacteria-host interactions and host variability in microbiologically uncontrolled conditions. While these difficulties can be partially resolved using gnotobiotic models harboring no or reduced microbiota, most host-microbe interaction studies are carried out in animal models with little relevance for fish farming. Here we studied host-microbiota-pathogen interactions in a germ-free and gnotobiotic model of rainbow trout (Oncorhynchus mykiss), one of the most widely cultured salmonids. We demonstrated that germ-free larvae raised in sterile conditions displayed no significant difference in growth after 35 days compared to conventionally-raised larvae, but were extremely sensitive to infection by Flavobacterium columnare, a common freshwater fish pathogen causing major economic losses worldwide. Furthermore, re-conventionalization with 11 culturable species from the conventional trout microbiota conferred resistance to F. columnare infection. Using mono-re-conventionalized germ-free trout, we identified that this protection is determined by a commensal Flavobacterium strain displaying antibacterial activity against F. columnare. Finally, we demonstrated that use of gnotobiotic trout is a suitable approach for the identification of both endogenous and exogenous probiotic bacterial strains protecting teleostean hosts against F. columnare. This study therefore establishes an ecologically-relevant gnotobiotic model for the study of host-pathogen interactions and colonization resistance in farmed fish.
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Enfermedades de los Peces/microbiología , Flavobacterium/fisiología , Vida Libre de Gérmenes , Interacciones Huésped-Patógeno , Microbiota , Oncorhynchus mykiss/microbiología , Animales , Acuicultura , Agua DulceRESUMEN
Tartary buckwheat belongs to the family Polygonaceae, which is a traditionally edible and medicinal plant. Due to its various bioactive compounds, the consumption of Tartary buckwheat is correlated to a wide range of health benefits, and increasing attention has been paid to its potential as a functional food. This review summarizes the main bioactive compounds and important bioactivities and health benefits of Tartary buckwheat, emphasizing its protective effects on metabolic diseases and relevant molecular mechanisms. Tartary buckwheat contains a wide range of bioactive compounds, such as flavonoids, phenolic acids, triterpenoids, phenylpropanoid glycosides, bioactive polysaccharides, and bioactive proteins and peptides, as well as D-chiro-inositol and its derivatives. Consumption of Tartary buckwheat and Tartary buckwheat-enriched products is linked to multiple health benefits, e.g., antioxidant, anti-inflammatory, antihyperlipidemic, anticancer, antidiabetic, antiobesity, antihypertensive, and hepatoprotective activities. Especially, clinical studies indicate that Tartary buckwheat exhibits remarkable antidiabetic activities. Various tartary buckwheat -based foods presenting major health benefits as fat and blood glucose-lowering agents have been commercialized. Additionally, to address the safety concerns, i.e., allergic reactions, heavy metal and mycotoxin contaminations, the quality control standards for Tartary buckwheat and its products should be drafted and completed in the future.
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Fagopyrum , Plantas Medicinales , Fagopyrum/química , Flavonoides/metabolismo , Antioxidantes/farmacología , Antioxidantes/metabolismo , GlicósidosRESUMEN
Vapor pressures and other thermodynamic properties of liquids, such as density and enthalpy of mixtures, are the key parameters in chemical engineering for designing new process units, and are also essential for understanding the physical chemistry, macroscopic and molecular behavior of fluid systems. In this work, vapor pressures between 278.15 and 323.15 K, densities and enthalpies of mixtures between 288.15 and 318.15 K for the binary mixture (2-propanol + 1,8-cineole) have been measured. From the vapor pressure data, activity coefficients and excess Gibbs energies were calculated via the Barker's method and the Wilson equation. Excess molar volumes and excess molar enthalpies were also obtained from the density and calorimetric measurements. Thermodynamic consistency test between excess molar Gibbs energies and excess molar enthalpies has been carried out using the Gibbs-Helmholtz equation. Robinson-Mathias, and Peng-Robinson-Stryjek-Vera together with volume translation of Peneloux equations of state (EoS) are considered, as well as the statistical associating fluid theory that offers a molecular vision quite suitable for systems having highly non-spherical or associated molecules. Of these three models, the first two fit the experimental vapor pressure results quite adequately; in contrast, only the last one approaches the volumetric behavior of the system. A brief comparison of the thermodynamic excess molar functions for binary mixtures of short-chain alcohol + 1,8-cineole (cyclic ether), or +di-n-propylether (lineal ether) is also included.
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1-Propanol , 2-Propanol , Eucaliptol , Termodinámica , Gases , PropanolesRESUMEN
Flavobacterium columnare causes columnaris disease in wild and cultured freshwater fish and is a major problem for sustainable aquaculture worldwide. The F. columnare type IX secretion system (T9SS) secretes many proteins and is required for virulence. The T9SS component GldN is required for secretion and gliding motility over surfaces. Genetic manipulation of F. columnare is inefficient, which has impeded identification of secreted proteins that are critical for virulence. Here, we identified a virulent wild-type F. columnare strain (MS-FC-4) that is highly amenable to genetic manipulation. This facilitated isolation and characterization of two deletion mutants lacking core components of the T9SS. Deletion of gldN disrupted protein secretion and gliding motility and eliminated virulence in zebrafish and rainbow trout. Deletion of porV disrupted secretion and virulence but not motility. Both mutants exhibited decreased extracellular proteolytic, hemolytic, and chondroitin sulfate lyase activities. They also exhibited decreased biofilm formation and decreased attachment to fish fins and other surfaces. Using genomic and proteomic approaches, we identified proteins secreted by the T9SS. We deleted 10 genes encoding secreted proteins and characterized the virulence of mutants lacking individual or multiple secreted proteins. A mutant lacking two genes encoding predicted peptidases exhibited reduced virulence in rainbow trout, and mutants lacking a predicted cytolysin showed reduced virulence in zebrafish and rainbow trout. The results establish F. columnare strain MS-FC-4 as a genetically amenable model to identify virulence factors. This may aid development of measures to control columnaris disease and impact fish health and sustainable aquaculture. IMPORTANCE Flavobacterium columnare causes columnaris disease in wild and aquaculture-reared freshwater fish and is a major problem for aquaculture. Little is known regarding the virulence factors involved in this disease, and control measures are inadequate. The type IX secretion system (T9SS) secretes many proteins and is required for virulence, but the secreted virulence factors are not known. We identified a strain of F. columnare (MS-FC-4) that is well suited for genetic manipulation. The components of the T9SS and the proteins secreted by this system were identified. Deletion of core T9SS genes eliminated virulence. Genes encoding 10 secreted proteins were deleted. Deletion of two peptidase-encoding genes resulted in decreased virulence in rainbow trout, and deletion of a cytolysin-encoding gene resulted in decreased virulence in rainbow trout and zebrafish. Secreted peptidases and cytolysins are likely virulence factors and are targets for the development of control measures.
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Enfermedades de los Peces , Infecciones por Flavobacteriaceae , Animales , Enfermedades de los Peces/microbiología , Infecciones por Flavobacteriaceae/microbiología , Infecciones por Flavobacteriaceae/veterinaria , Flavobacterium , Proteómica , Virulencia , Pez CebraRESUMEN
Brown algae are ubiquitously distributed in the NW coastline of the Iberian Peninsula, where they stand as an underexploited resource. In this study, five solvents were applied to the extraction of pigments from nine brown algae, followed by their determination and quantification by HPLC-DAD. A total of 13 compounds were detected: Six were identified as chlorophylls, six were classified as xanthophylls, and one compound was reported as a carotene. Fucoxanthin was reported in all extracts, which is the most prominent pigment of these algae. Among them, L. saccharina and U. pinnatifida present the highest concentration of fucoxanthin (4.5-4.7 mgâg-1 dry weight). Ethanol and acetone were revealed as the most efficient solvents for the extraction of pigments, showing a maximal value of 11.9 mg of total pigments per gram of dry alga obtained from the ethanolic extracts of H. elongata, followed by the acetonic extracts of L. ochroleuca. Indeed, ethanol was also revealed as the most efficient solvent according to its high extraction yield along all species evaluated. Our results supply insights into the pigment composition of brown algae, opening new perspectives on their commercial exploitation by food, pharmaceutical, and cosmeceutical industries.
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Phaeophyceae/química , Pigmentos Biológicos/química , Solventes/química , Carotenoides/química , Carotenoides/aislamiento & purificación , Clorofila/química , Clorofila/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Pigmentos Biológicos/aislamiento & purificación , Agua de Mar , Xantófilas/química , Xantófilas/aislamiento & purificaciónRESUMEN
Algae are underexplored resources in Western countries and novel approaches are needed to boost their industrial exploitation. In this work, eight edible seaweeds were subjected to their valorization in terms of nutritional characterization, thermochemical properties, and bioactive profile. Our results suggest that seaweeds present a rich nutritional profile, in which carbohydrates are present in high proportions, followed by a moderate protein composition and a valuable content of ω-3 polyunsaturated fatty acids. The thermochemical characterization of seaweeds showed that some macroalgae present a low ash content and high volatile matter and carbon fixation rates, being promising sources for alternative biofuel production. The bioactive profile of seaweeds was obtained from their phenolic and carotenoid content, together with the evaluation of their associated bioactivities. Among all the species analyzed, Porphyra purpurea presented a balanced composition in terms of carbohydrates and proteins and the best thermochemical profile. This species also showed moderate anti-inflammatory activity. Additionally, Himanthalia elongata extracts showed the highest contents of total phenolics and a moderate carotenoid content, which led to the highest rates of antioxidant activity. Overall, these results suggest that seaweeds can be used as food or functional ingredient to increase the nutritional quality of food formulations.
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Biocombustibles , Valor Nutritivo , Fitoquímicos/farmacología , Algas Marinas/química , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Porphyra/químicaRESUMEN
Neuropathic pain is a form of chronic pain arising from damage of the neural cells that sense, transmit or process sensory information. Given its growing prevalence and common refractoriness to conventional analgesics, the development of new drugs with pain relief effects constitutes a prominent clinical need. In this respect, drugs that reduce activity of sensory neurons by modulating ion channels hold the promise to become effective analgesics. Here, we evaluated the mechanical antinociceptive effect of IQM-PC332, a novel ligand of the multifunctional protein downstream regulatory element antagonist modulator (DREAM) in rats subjected to chronic constriction injury of the sciatic nerve as a model of neuropathic pain. IQM-PC332 administered by intraplantar (0.01-10 µg) or intraperitoneal (0.02-1 µg/kg) injection reduced mechanical sensitivity by ≈100% of the maximum possible effect, with ED50 of 0.27 ± 0.05 µg and 0.09 ± 0.01 µg/kg, respectively. Perforated-patch whole-cell recordings in isolated dorsal root ganglion (DRG) neurons showed that IQM-PC332 (1 and 10 µM) reduced ionic currents through voltage-gated K+ channels responsible for A-type potassium currents, low, T-type, and high voltage-activated Ca2+ channels, and transient receptor potential vanilloid-1 (TRPV1) channels. Furthermore, IQM-PC332 (1 µM) reduced electrically evoked action potentials in DRG neurons from neuropathic animals. It is suggested that by modulating multiple DREAM-ion channel signaling complexes, IQM-PC332 may serve a lead compound of novel multimodal analgesics.
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Analgésicos/farmacología , Proteínas de Interacción con los Canales Kv/metabolismo , Neuralgia/tratamiento farmacológico , Neuralgia/etiología , Traumatismos de los Nervios Periféricos/complicaciones , Animales , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/metabolismo , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/metabolismo , Ligandos , Masculino , Potenciales de la Membrana/efectos de los fármacos , Neuralgia/metabolismo , Traumatismos de los Nervios Periféricos/metabolismo , Ratas , Ratas Sprague-Dawley , Nervio Ciático/efectos de los fármacos , Nervio Ciático/metabolismo , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismoRESUMEN
Seaweeds are industrially exploited for obtaining pigments, polysaccharides, or phenolic compounds with application in diverse fields. Nevertheless, their rich composition in fiber, minerals, and proteins, has pointed them as a useful source of these components. Seaweed proteins are nutritionally valuable and include several specific enzymes, glycoproteins, cell wall-attached proteins, phycobiliproteins, lectins, or peptides. Extraction of seaweed proteins requires the application of disruptive methods due to the heterogeneous cell wall composition of each macroalgae group. Hence, non-protein molecules like phenolics or polysaccharides may also be co-extracted, affecting the extraction yield. Therefore, depending on the macroalgae and target protein characteristics, the sample pretreatment, extraction and purification techniques must be carefully chosen. Traditional methods like solid-liquid or enzyme-assisted extraction (SLE or EAE) have proven successful. However, alternative techniques as ultrasound- or microwave-assisted extraction (UAE or MAE) can be more efficient. To obtain protein hydrolysates, these proteins are subjected to hydrolyzation reactions, whether with proteases or physical or chemical treatments that disrupt the proteins native folding. These hydrolysates and derived peptides are accounted for bioactive properties, like antioxidant, anti-inflammatory, antimicrobial, or antihypertensive activities, which can be applied to different sectors. In this work, current methods and challenges for protein extraction and purification from seaweeds are addressed, focusing on their potential industrial applications in the food, cosmetic, and pharmaceutical industries.
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Fraccionamiento Químico/métodos , Hidrolisados de Proteína/aislamiento & purificación , Hidrolisados de Proteína/uso terapéutico , Péptidos/aislamiento & purificación , Péptidos/uso terapéutico , Fenoles/aislamiento & purificación , Polisacáridos , Algas Marinas/químicaRESUMEN
Hydrolytic extracellular enzymes degrading host tissues potentially play a role in bacterial pathogenesis. Flavobacterium psychrophilum is an important bacterial pathogen of salmonid fish reared in freshwater throughout the world. Diversity among isolates has been described at the phenotypic, serological, and genomic levels, but the links between these various traits remain poorly understood. Using a genome-wide association study, we identified a gene encoding a novel elastinolytic enzyme in F. psychrophilum To formally demonstrate enzymatic activity, this gene (FP0506 from strain JIP 02/86) was expressed in the elastinolysis-deficient strain OSU THCO2-90, resulting in proficient elastin-degrading cells. The encoded protein is predicted to be a cell-surface-exposed lipoprotein with no homology to previously reported elastases. FP0506 might belong to the zincin tribe and gluzincin clan of metalloproteases, and this new elastase-encoding gene seems to be present only in some members of the family FlavobacteriaceaeIMPORTANCE Elastin is an important proteinaceous component of vertebrate connective tissues (e.g., blood vessels, lung, and skin), to which it confers elasticity. Elastases have been identified in a number of pathogenic bacteria. They are thought to be required for tissue penetration and dissemination, acting as "spreading factors." Flavobacterium psychrophilum is a devastating bacterial pathogen of salmonid fish (salmon and trout) that is responsible for severe economic losses worldwide. This pathogen displays strong proteolytic activities. Using a variety of techniques, including genome comparisons, we identified a gene encoding a novel elastase in F. psychrophilum The encoded protein is predicted to be a cell-surface-exposed lipoprotein with no homology to previously reported elastases. In addition, this elastase likely belongs to a new family of proteases that seems to be present only in some members of this important group of bacteria.
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Proteínas Bacterianas/metabolismo , Elastina/metabolismo , Enfermedades de los Peces/microbiología , Infecciones por Flavobacteriaceae/veterinaria , Flavobacterium/enzimología , Metaloproteasas/metabolismo , Animales , Proteínas Bacterianas/genética , Infecciones por Flavobacteriaceae/microbiología , Flavobacterium/química , Flavobacterium/genética , Flavobacterium/aislamiento & purificación , Genoma Bacteriano , Estudio de Asociación del Genoma Completo , Metaloproteasas/genética , Oncorhynchus mykiss/microbiologíaRESUMEN
The rates of production of secondary metabolites obtained by employing conventional plant breeding may be low for practical purposes. Thus, innovative approaches for increasing their rates of production are being developed. Here, we propose the use of elicited plant suspension cultured cells (PSCC) with cyclodextrins (CDs) as an alternative method for the production of bioactive compounds from Bryophyllum species. For this purpose, we analyzed the effects of methyl-ß-cyclodextrin and 2-hydroxypropyl-ß-cyclodextrin on cell culture growth and on the intra- and extracellular production of phenols and flavonoids. Results clearly show that CDs enhance the biosynthesis of polyphenols by PSCC favoring their accumulation outside the cells. CDs shift the homeostatic equilibrium by complexing extracellular phenolics, causing stress in cells that respond by increasing the production of intracellular phenolics. We also analyzed the radical scavenging activity of the culture medium extracts against 2,2-diphenyl-1-pycrilhydrazyl (DPPH) radical, which increased with respect to the control samples (no added CDs). Our results suggest that both the increase in the production of polyphenols and their radical scavenging activity are a consequence of their inclusion in the CD cavities. Overall, based on our findings, CDs can be employed as hosts for increasing the production of polyphenols from Bryophyllum species.
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Ciclodextrinas/metabolismo , Kalanchoe/metabolismo , Células Vegetales/efectos de los fármacos , Células Vegetales/metabolismo , Antioxidantes/farmacología , Células Cultivadas , Ciclodextrinas/farmacología , Relación Dosis-Respuesta a Droga , Espacio Extracelular/metabolismo , Espacio Intracelular/metabolismo , Kalanchoe/efectos de los fármacos , Cinética , Fenoles/metabolismoRESUMEN
Somatic embryogenesis receptor-like kinase 1 (SERK1) is a membrane receptor that might serve as common co-regulator of plant cell differentiation processes by forming heterodimers with specific receptor-like kinases. The Coffea canephora SERK1 homolog (CcSERK1) was cloned in this work, and its early function in the transcription of embryogenesis master genes and of genes encoding proteins involved in auxin metabolism was investigated by externally manipulating its expression in embryogenic leaf explants, before the appearance of embryogenic structures. Overexpression of CcSERK1 early during embryogenesis caused an increase in the number of somatic embryos when the 55-day process was completed. Suppression of CcSERK1 expression by RNA interference almost abolished somatic embryogenesis. Real time-PCR experiments revealed that the transcription of the CcAGL15, CcWUS, CcBBM, CcPKL, CcYUC1, CcPIN1 and CcPIN4 homologs was modified in direct proportion to the expression of CcSERK1 and that only CcLEC1 was inversely affected by the expression levels of CcSERK1. The expression of the CcYUC4 homolog was induced to more than 80-fold under CcSERK1 overexpression conditions, but it was also induced when CcSERK1 expression was silenced. The level of CcTIR1 was not affected by CcSERK1 overexpression but was almost abolished during CcSERK1 silencing. These results suggest that CcSERK1 co-regulates the induction of somatic embryogenesis in Coffea canephora by early activation of YUC-dependent auxin biosynthesis, auxin transport mediated by PIN1 and PIN4, and probably auxin perception by the TIR1 receptor, leading to the induction of early-stage homeotic genes (CcAGL15, CcWUS, CcPKL and CcBBM) and repression of late-stage homeotic genes (CcLec1).
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Coffea/genética , Coffea/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas Quinasas/genética , Semillas/genética , Clonación Molecular , Expresión Génica Ectópica , Regulación de la Expresión Génica de las Plantas , Familia de Multigenes , Filogenia , Hojas de la Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Proteínas Quinasas/metabolismo , Semillas/crecimiento & desarrollo , Transcripción GenéticaRESUMEN
In this work we report the preparation of mixtures of several alkyl glyceryl ethers, as hydrogen bond donor compounds, with two ammonium salts, choline chloride and N,N,N-triethyl-2,3-dihydroxypropan-1-aminium chloride. The stability of the mixtures at different molar ratios and temperatures has been evaluated in order to determine the formation of low melting mixtures. Liquid and stable mixtures have been characterized and their physico-chemical properties such as density, viscosity, refractive index, conductivity and surface tension have been measured in the temperature range of 293.15 K to 343.15 K. Comparison of the mixtures prepared herein with the ones containing glycerol and choline chloride evidences the possibility of tuning the physico-chemical properties by changing the substitution pattern in the hydrogen bond donor compound or in the ammonium salt, thus broadening the scope of application of these mixtures.
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Flavobacterium psychrophilum is an important fish pathogen, responsible for Cold Water Disease, with a significant economic impact on salmonid farms worldwide. In spite of this, little is known about the bacterial physiology and pathogenesis mechanisms, maybe because it is difficult to manipulate, being considered a fastidious microorganism. Mutants obtained using a Tn4351 transposon were screened in order to identify those with alteration in colony morphology, colony spreading and extracellular proteolytic activity, amongst other phenotypes. A F. psychrophilum mutant lacking gliding motility showed interruption of the FP1638 locus that encodes a putative type-2 glycosyltransferase (from here on referred to as fpgA gene, Flavobacterium psychrophilum glycosyltransferase). Additionally, the mutant also showed a decrease in the extracellular proteolytic activity as a consequence of down regulation in the fpgA mutant background of the fpp2-fpp1 operon promoter, responsible for the major extracellular proteolytic activity of the bacterium. The protein glycosylation profile of the parental strain showed the presence of a 22 kDa glycosylated protein which is lost in the mutant. Complementation with the fpgA gene led to the recovery of the wild-type phenotype. LD50 experiments in the rainbow trout infection model show that the mutant was highly attenuated. The pleiotropic phenotype of the mutant demonstrated the importance of this glycosyltranferase in the physiology and virulence of the bacterium. Moreover, the fpgA mutant strain could be considered a good candidate for the design of an attenuated vaccine.
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Proteínas Bacterianas/genética , Enfermedades de los Peces/microbiología , Infecciones por Flavobacteriaceae/veterinaria , Flavobacterium/enzimología , Flavobacterium/patogenicidad , Glicosiltransferasas/genética , Oncorhynchus mykiss , Animales , Proteínas Bacterianas/metabolismo , Enfermedades de los Peces/enzimología , Infecciones por Flavobacteriaceae/enzimología , Infecciones por Flavobacteriaceae/microbiología , Flavobacterium/genética , Glicosiltransferasas/metabolismo , Dosificación Letal Mediana , VirulenciaRESUMEN
BACKGROUND: In subjects with hypercholesterolaemia, cholesterol values remain above guideline levels. One of the limiting factors to the achievement of goals in such patients is therapeutic non-adherence. The aim of this study is to assess the effectiveness of an intervention designed to improve control of hypercholesterolaemic patients, consisting of a combined strategy that would include the delivery of printed information, treatment-compliance check cards and the dispatch of text messages as complementary measures in support of the intervention at the general practitioner's practice. METHODS/DESIGN: A randomised, parallel-group clinical trial will be conducted at the family medicine outpatient facilities of eight health centres in three of Spain's Autonomous Regions (Comunidades Autónomas), covering a total of 358 subjects aged 18 years or over with diagnosis of hypercholesterolaemia. Patients in the intervention group will be supplied with printed material with information on the disease and its management, mobile-telephone text messages with guideline summaries, reminders of forthcoming appointments and/or arrangements for making new appointments in the event of non-attendance, and self-report cards to check compliance with recommendations. Both groups -intervention and control- will receive routine recommendations from their physicians in accordance with current European clinical practice guidelines for hypercholesterolaemia and cardiovascular risk management. As regards the measurements to be made, the main variable is the proportion of subjects who attain the low density lipoprotein cholesterol levels set as a target across a follow-up period of 24 months. The secondary variables are as follows: adherence to recommendations on lifestyle and adherence to drug treatment; variation in lipid profiles and cardiovascular risk levels; appearance of cardiovascular events; physical activity; food consumption; smoking habit; anthropometric measures; blood pressure; health problems; use of hypolipidaemic agents; socio-demographic data; beliefs and expectations about preventive recommendations; and degree of satisfaction with the combined strategy. DISCUSSION: Should this intervention prove effective, a recommendation could be issued on the application of this combined strategy to subjects with hypercholesterolaemia. It is a simple, relatively inexpensive intervention. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02314663.
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Hipercolesterolemia/terapia , Cooperación del Paciente , Atención Primaria de Salud/métodos , Sistemas Recordatorios , Enfermedades Cardiovasculares/prevención & control , Conductas Relacionadas con la Salud , Humanos , Hipercolesterolemia/complicaciones , Hipercolesterolemia/tratamiento farmacológico , Estilo de Vida , Educación del Paciente como Asunto , Factores de Riesgo , Envío de Mensajes de TextoRESUMEN
Plant imprinted genes show parent-of-origin expression in seed endosperm, but little is known about the nature of parental imprints in gametes before fertilization. We show here that single differentially methylated regions (DMRs) correlate with allele-specific expression of two maternally expressed genes in the seed and that one DMR is differentially methylated between gametes. Thus, plants seem to have developed similar strategies as mammals to epigenetically mark imprinted genes.
Asunto(s)
Epigénesis Genética , Impresión Genómica , Plantas/genética , Islas de CpG , Metilación de ADN , ADN de Plantas/química , ADN de Plantas/genética , Regulación de la Expresión Génica de las Plantas , Células Germinativas/metabolismo , Plantas/embriología , Plantas Modificadas Genéticamente , Zea mays/genéticaRESUMEN
The increasing trend regarding the use of plastics has arisen an exponential concern on the fate of their derived products to the environment. Among these derivatives, microplastics and nanoplastics (MNPs) have been featured for their associated environmental impact due to their low molecular size and high surface area, which has prompted their ubiquitous transference among all environmental interfaces. Due to the heterogenous chemical composition of MNPs, the study of these particles has focused a high number of studies, as a result of the myriad of associated physicochemical properties that contribute to the co-transference of a wide range of contaminants, thus becoming a major challenge for the scientific community. In this sense, both primary and secondary MNPs are well-known to be adscribed to industrial and urbanized areas, from which they are massively released to the environment through a multiscale level, involving the atmosphere, hydrosphere, and lithosphere. Consequently, much research has been conducted on the understanding of the interconnection between those interfaces, that motivate the spread of these contaminants to biological systems, being mostly represented by the biosphere, especially phytosphere and, finally, the anthroposphere. These findings have highlighted the potential hazardous risk for human health through different mechanisms from the environment, requiring a much deeper approach to define the real risk of MNPs exposure. As a result, there is a gap of knowledge regarding the environmental impact of MNPs from a high-throughput perspective. In this review, a metabolomics-based overview on the impact of MNPs to all environmental interfaces was proposed, considering this technology a highly valuable tool to decipher the real impact of MNPs on biological systems, thus opening a novel perspective on the study of these contaminants.