1,875 research outputs found

    Chemotactic response of the flavonoid daidzein and its effect on the composition of the rumen bacterial community

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    Daidzein is one of common metabolites in plants and has chemotactic effect on soil bacteria that colonize the plants. There are several tests to assess bacterial chemotaxis, but none focused on rumen bacteria. Therefore, the aim of this study was to test the chemotactic response of the rumen microflora towards daidzein using a standardized bacterial chemotaxis assay. It consisted in a modifying capillary technique and employing technology for measuring in vitro gas production. Ruminal fluids and cellulose were used as controls. The response of bacteria to daidzein was greater than the response to cellulose, supporting the hypothesis that when fodder is chewed by the ruminant it releases daidzein which can attract rumen bacteria towards feed particles (chemotaxis) for attachment and subsequent degradation

    Glucocorticoid Resistance: Interference between the Glucocorticoid Receptor and the MAPK Signalling Pathways

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    Endogenous glucocorticoids (GCs) are steroid hormones that signal in virtually all cell types to modulate tissue homeostasis throughout life. Also, synthetic GC derivatives (pharmacological GCs) constitute the first-line treatment in many chronic inflammatory conditions with unquestionable therapeutic benefits despite the associated adverse effects. GC actions are principally mediated through the GC receptor (GR), a ligand-dependent transcription factor. Despite the ubiquitous expression of GR, imbalances in GC signalling affect tissues differently, and with variable degrees of severity through mechanisms that are not completely deciphered. Congenital or acquired GC hypersensitivity or resistance syndromes can impact responsiveness to endogenous or pharmacological GCs, causing disease or inadequate therapeutic outcomes, respectively. Acquired GC resistance is defined as loss of efficacy or desensitization over time, and arises as a consequence of chronic inflammation, affecting around 30% of GC-treated patients. It represents an important limitation in the management of chronic inflammatory diseases and cancer, and can be due to impairment of multiple mechanisms along the GC signalling pathway. Among them, activation of the mitogen-activated protein kinases (MAPKs) and/or alterations in expression of their regulators, the dual-specific phosphatases (DUSPs), have been identified as common mechanisms of GC resistance. While many of the anti-inflammatory actions of GCs rely on GR-mediated inhibition of MAPKs and/or induction of DUSPs, the GC anti-inflammatory capacity is decreased or lost in conditions of excessive MAPK activation, contributing to disease susceptibility in tissue- and disease- specific manners. Here, we discuss potential strategies to modulate GC responsiveness, with the dual goal of overcoming GC resistance and minimizing the onset and severity of unwanted adverse effects while maintaining therapeutic potential

    Electrochemical behaviour of gamma hydroxybutyric acid at a platinum electrode in acidic medium

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    The electrooxidation of Gamma Hydroxybutyric Acid (GHB) on a polycrystalline platinum electrode is studied by cyclic voltammetry in acidic medium. Two oxidation peaks, A and B, are obtained in the positive scan within the potential range of the double layer region and of the platinum oxide region, respectively. In the negative going potential sweep an inverted oxidation peak with an onset partially overlapping with the tail of the cathodic peak for the reduction of the platinum oxide formed during the anodic scan is obtained (peak C). This inverted peak can be observed at a potential close to +0.2 V (vs Ag/AgCl at pH 2) and separated 0.4 and 0.8 V from the two other oxidation peaks obtained during the anodic scan and in such conditions that the surface is particularly activated to favour this electrochemical process. The response obtained in the electronic current for the different peaks when GHB concentration and scan rate were changed to allows inferring that these are the result of a potential dependent mechanism. The behaviour observed is according with the oxidation of the alcohol group to the corresponding aldehyde and carboxylic acid (succinic acid) as main products

    Dynamic semantic ontology generation: a proposal for social robots

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    [Abstract] During a human-robot interaction by dialogue/voice, the robot cannot extract semantic meaning from the words used, limiting the intervention itself. Semantic knowledge could be a solution by structuring information according to its meaning and its semantic associations. Applied to social robotics, it could lead to a natural and fluid human-robot interaction. Ontologies are useful representations of semantic knowledge, as they capture the relationships between objects and entities. This paper presents new ideas for ontology generation using already generated ontologies as feedback in an iterative way to do it dynamically. This paper also collects and describes the concepts applied in the proposed methodology and discusses the challenges to be overcome.Ministerio de Ciencia, Innovación y Universidades; RTI2018-096338-B-I0

    Comparative study of gamma-hidroxybutiric acid (GHB) and other derivative compounds by spectroelectrochemistry raman (SERS) on platinum surface.

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    The electrochemical behaviour of gamma-hydroxybutyric acid (GHB), the cyclic lactone derivative (GBL), 1-butanol, butyric acid and succinic acid on a platinum electrode in acidic medium has been studied by means of Raman spectroelectrochemistry using the SERS effect. Only GHB and 1-butanol were found to be electroactive substances that can form the acid product mainly and other species in minor proportion through the electro-catalytic oxidation reaction of alcohol group. The interaction of all these molecules with the platinum and platinum oxides, generated during the electrodic process has been investigated in a wide interval of potentials. Succinic acid was found to play the role of both intermediate (to produce the conjugate derivative) and product in GHB electrocatalytic oxidation. Likewise, the electrooxidation of 1-butanol produced butyric acid predominantly. The carbon (CH2) and the ring skeletons presented a predominant interaction with the platinum oxide surface for 1-butanol and GBL, respectively

    Cyano-and ketone-containing selenoesters as multi-target compounds against resistant cancers

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    Fifteen selenocompounds, comprising of eight ketone-containing selenoesters (K1–K8, also known as oxoselenoesters) and seven cyano-containing selenoesters (N1–N7, known also as cyanoselenoesters), have been designed, synthesized, and evaluated as novel anticancer agents. These compounds are derivatives of previously reported active selenoesters and were prepared following a three-step one-pot synthetic route. The following evaluations were performed in their biological assessment: cytotoxicity determination, selectivity towards cancer cells in respect to non-cancer cells, checkerboard combination assay, ABCB1 inhibition and inhibition of ABCB1 ATPase activity, apoptosis induction, and wound healing assay. As key results, all the compounds showed cytotoxicity against cancer cells at low micromolar concentrations, with cyanoselenoesters being strongly selective. All of the oxoselenoesters, except K4, were potent ABCB1 inhibitors, and two of them, namely K5 and K6, enhanced the activity of doxorubicin in a synergistic manner. The majority of these ketone derivatives modulated the ATPase activity, showed wound healing activity, and induced apoptosis, with K3 being the most potent, with a potency close to that of the reference compound. To summarize, these novel derivatives have promising multi-target activity, and are worthy to be studied more in-depth in future works to gain a greater understanding of their potential applications against cancer.The study was supported by the projects SZTE ÁOK-KKA 2018/270-62-2 of the University of Szeged, Faculty of Medicine and GINOP-2.3.2-15-2016-00038 (Hungary); and Consejo Superior de Investigaciones Científicas (CSIC, Spain, project LINKA20285). This research was funded by VISEGRAD FUND, grant number 22010090; and by the mobility project from the Czech Ministry of Education, Youth and Sports INTER-COST, grant number LTC19007. This article is based upon work from COST Action 17104 , supported by COST (European Cooperation in Science and Technology), (http://www.cost.eu, accessed on 17 September 2021). The study was supported also by two cultural associations: “Trevinca” and “Iniciativas Ropelanas”

    Consensus document on the progression and treatment response criteria in gastroenteropancreatic neuroendocrine tumors

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    Purpose Gastroenteropancreatic neuroendocrine tumors are a heterogeneous group of low incidence neoplasms characterized by a low proliferative activity and slow growth. Their response to targeted therapies is heterogeneous and often does not lead to tumor shrinkage. Thus, evaluation of the therapeutic response should difer from other kind of tumors. Methods To answer relevant questions about which techniques are best in the assessment of progression or treatment response a RAND/UCLA-based consensus process was implemented. Relevant clinical questions were listed followed by a systematic search of the literature. The expert panel answered all questions with recommendations, combining available evidence and expert opinion. Recommendations were validated through a questionnaire and a participatory meeting. Results Expert recommendations regarding imaging tools for tumor assessment and evaluation of progression were agreed upon. Available imaging techniques were reviewed and recommendations for best patient monitoring practice and the best way to evaluate treatment response were formulated

    Epilepsy and neuropsychiatric comorbidities in mice carrying a recurrent Dravet syndrome SCN1A missense mutation

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    Dravet Syndrome (DS) is an encephalopathy with epilepsy associated with multiple neuropsychiatric comorbidities. In up to 90% of cases, it is caused by functional happloinsufficiency of the SCN1A gene, which encodes the alpha subunit of a voltage-dependent sodium channel (Nav1.1). Preclinical development of new targeted therapies requires accessible animal models which recapitulate the disease at the genetic and clinical levels. Here we describe that a C57BL/6 J knock-in mouse strain carrying a heterozygous, clinically relevant SCN1A mutation (A1783V) presents a full spectrum of DS manifestations. This includes 70% mortality rate during the first 8 weeks of age, reduced threshold for heat-induced seizures (4.7 °C lower compared with control littermates), cognitive impairment, motor disturbances, anxiety, hyperactive behavior and defects in the interaction with the environment. In contrast, sociability was relatively preserved. Electrophysiological studies showed spontaneous interictal epileptiform discharges, which increased in a temperature-dependent manner. Seizures were multifocal, with different origins within and across individuals. They showed intra/inter-hemispheric propagation and often resulted in generalized tonic-clonic seizures. 18F-labelled flourodeoxyglucose positron emission tomography (FDG-PET) revealed a global increase in glucose uptake in the brain of Scn1aWT/A1783V mice. We conclude that the Scn1aWT/A1783V model is a robust research platform for the evaluation of new therapies against DS

    NIVEL DE PREFERENCIA DE MERMELADA ELABORADA CON ROCOTO (Capsicum pubescens) Y PIÑA (Ananas comosus)

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    The pace of life of the current population has led to changes in eating habits and people are likely to suffer from gastric problems. The rocoto chilli is palatable, contains vitamins, antioxidants, and has been reported that consumption of chilies benefits the digestive system. This research aimed to evaluate acceptance and consumer preference to the processed food from the binary combination of a natural fruit pulp and rocoto chilli ; two differents jams formulations to pineapple pulp and rocoto chilli pulp (ratios 1:4 and 1:8) were developed, being used sugar, pectin , potassium sorbate and citric acid, rocoto chilli pulp and pineapple pulp. The preference degree of potential consumer (53 judges aged 17 to 50 years old) was evaluated, significant differences were detected between the two jams formulations (α=0,01), 02 formulation being preferred; 62,26% of consumers expressed a willingness to purchase the preferred jam. The attributes sensory evaluated: color, smell, consistency and flavor, semi-trained panel (16 judges) was used, significant differences were detected in the intensity of color (α<0,05), the other attributes: smell, taste and consistency, judges did not detect difference between the two formulations (α=0,05). The 01 formulation pH 3.45; 75°Brix and 5700 cp at 60 rpm; the 02 formulation showed pH 3,35; 66°Brix and 4500 cp at 60 rpm.El ritmo de vida acelerado de la población actual ha producido cambios en los hábitos alimenticios y las personas están propensas a sufrir problemas gástricos. El rocoto tiene sabor agradable, contiene vitaminas, antioxidantes y su consumo beneficia al sistema digestivo. Esta investigación tuvo como propósito evaluar la aceptación y preferencia del consumidor ante un producto elaborado con la combinación binaria de pulpa de rocoto y un fruto natural; se desarrollaron dos formulaciones de mermelada de rocoto:piña (proporciones 1:4 y 1:8), empleándose pulpa de rocoto, pulpa de piña, azúcar, pectina, sorbato de potasio y ácido cítrico. Se evaluó el nivel de preferencia del consumidor potencial (53 jueces con edades entre 17 a 50 años) detectándose diferencias significativas entre las dos formulaciones de mermelada (α=0,01), prefiriéndose la formulación 02; el 62,26% de los consumidores manifestaron buena disposición para la compra de la mermelada preferida. Se empleó un panel semientrenado (16 jueces) para la evaluación sensorial de los atributos: color, olor, consistencia y sabor; se detectaron diferencias significativas en la intensidad del color (α>0,05), en la evaluación de los atributos olor, sabor y consistencia los jueces no detectaron diferencia entre las dos formulaciones (α=0,05). El análisis fisicoquímico de la formulación 01: pH 3,45; 75°Brix y 5700 cp a 60 rpm; la formulación 02: pH 3,35; 66 °Brix y 4500 cp a 60 rpm
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