Browsing by Subject "Inhibition"

Now showing 1 - 6 of 6
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    Cognitive flexibility and response inhibition in patients with Obsessive-Compulsive Disorder and Generalized Anxiety Disorder
    (Elsevier, 2020) Rosa-Alcázar, Angel; Olivares-Olivares, Pablo; Martínez-Esparza, Inma; Parada-Navas, Jose Luis; Rosa-Alcázar, Ana Isabel; Olivares-Rodríguez, José; Personalidad, Evaluación y Tratamiento Psicológicos
    Background/Objective: The main aim of this study was to analyze differences in inhibition and cognitive flexibility, taking into account some variables that may influence results (non verbal reasoning, depression, anxiety, intolerance of uncertainty, comorbidity, medication consump- tion). Method: The participants were 95 adults aged 17-61 years old (M = 33.48, SD = 11.13), primary (most severe) Generalized Anxiety Disorder or Obsessive-Compulsive Disorder and a healthy control group. Neuropsychological neasures were completed using computerized Wisconsin Card Sorting Test, Stroop Color Word Test and Go/NoGo Task. Results: Clinical groups presented worse results in cognitive flexibility to the control group. The obsessive-compulsive group showed worse scores in flexibility than the generalized anxiety group, once non-verbal reasoning and tolerance to uncertainty were controlled. Comorbidity and medication use did not affect results in the obsessive compulsive group but did however influence the generalized anxiety group. Conclusions: Cognitive flexibility could be included treatment in the treatment of obsessive- compulsive disorder and generalized anxiety disorder.
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    Considerations about the inhibition of monophenolase and diphenolase activities of tyrosinase. Characterization of the inhibitor concentration which generates 50 % of inhibition, type and inhibition constants. A review
    (Elsevier, 2024-04-10) García Molina, Pablo; Saura Sanmartín, Adrián; Berná Cánovas, José; Muñoz Muñoz, Jose Luis; García Cánovas, Francisco; García Molina, Francisco; Rodríguez López, José Neptuno; Teruel Puche, José Antonio; Saura Sanmartín, Adrián; García Molina, Francisco; Química Orgánica
    Tyrosinase is a copper oxidase enzyme which catalyzes the first two steps in the melanogenesis pathway, L tyrosine to L-dopa conversion and, then, to o-dopaquinone and dopachrome. Hypopigmentation and, above all, hyperpigmentation issues can be originated depending on their activity. This enzyme also promotes the browning of fruits and vegetables. Therefore, control of their activity by regulators is research topic of great relevance. In this work, we consider the use of inhibitors of monophenolase and diphenolase activities of the enzyme in order to accomplish such control. An experimental design and data analysis which allow the accurate calculation of the degree of inhibition of monophenolase activity (iM) and diphenolase activity (iD) are proposed. The IC50 values (amount of inhibitor that causes 50 % inhibition at a fixed substrate concentration) can be calculated for the two activities and from the values of ICM 50 (monophenolase) and ICD 50(diphenolase). Addi tionally, the strength and type of inhibition can be deduced from these values. The data analysis from these ICD 50 values allows to obtain the values of Kapp I1 or Kapp I2 , or Kapp I1 and Kapp I3 from the values of ICM 50. In all cases, the values of the different Kapp I must satisfy their relationship with ICM 50 and ICD 50.
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    Disease-causing mutations in the serpin antithrombin reveal a keydomaincritical for inhibiting protease activities
    (Elsevier, American Society for Biochemistry and Molecular Biology , 2017-10-06) Águila Martínez, Sonia; Izaguirre, G.; Vicente García, Vicente; Martínez-Martínez, I.; Olson, S. T.; Corral de la Calle, Javier; Medicina Interna
    Antithrombin mainly inhibits factor Xa and thrombin. The reactive center loop (RCL) is crucial for its interactions with its protease targets and is fully inserted into the A-sheet after its cleavage, causing translocation of the covalently linked protease to the opposite end of the A-sheet. Antithrombin variants with altered RCL hinge residues behave as substrates rather than inhibitors, resulting in stoichiometries of inhibition greater than one. Other antithrombin residues have been suggested to interfere with RCL insertion or the stability of the antithrombin–protease complex, but available crystal structures or mutagenesis studies have failed to identify such residues. Here, we characterized two mutations, S365L and I207T, present in individuals with type II antithrombin deficiency and identified a new antithrombin functional domain. S365L did not form stable complexes with thrombin or factor Xa, and the I207T/I207A variants inhibited both proteases with elevated stoichiometries of inhibition. Close proximity of Ile-207 and Ser-365 to the inserted RCL suggested that the preferred reaction of these mutants as protease substrates reflects an effect on the rate of the RCL insertion and protease translocation. However, both residues lie within the final docking site for the protease in the antithrombin–protease complex, supporting the idea that the enhanced substrate reactions may result from an increased dissociation of the final complexes. Our findings demonstrate that the distal end of the antithrombin A-sheet is crucial for the last steps of protease inhibition either by affecting the rate of RCL insertion or through critical interactions with proteases at the end of the A-sheet.
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    Effect of preventive and simultaneous inoculations of Bacillus amyloliquefaciens (Fukumoto) strains on conidial germination of Botrytis cinerea Pers.:Fr.
    (Universidad de Murcia, 2018) Hamdache, Ahlem; Ezziyyani, Mohammed; Lamarti, Ahmed
    Botrytis cinerea es un patógeno fúngico necrotrófico de varias plantas distribuido en todo el mundo. En el presente estudio se analizó el efecto de nueve aislados bacterianos sobre la germinación de conidios de B. cinerea. Los aislados se identificaron como Bacillus amyloliquefaciens. Para evaluar la eficacia de los aislados, se realizaron confrontaciones duales tanto preventivas como simultáneas con los conidios de B. cinerea. Los resultados mostraron que cinco aislados fueron más eficaces cuando se coinocularon simultáneamente con el patógeno. Cuatro aislados fueron más eficaces cuando se inocularon previamente cuatro horas antes el patógeno. La cepa denominada B24, mostró una inhibición de (84.04%) en concentraciones muy bajas (3x103 UFC/ml) y la cepa RA9 fue la cepa menos eficaz.
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    G protein-gated inwardly rectifying K+ (GIRK/Kir3) channels: Molecular, cellular, and subcellular diversity
    (Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2025) Martín Belmonte, Alejandro; Aguado, Carolina; Alfaro Ruíz, Rocio; Luján, Rafael
    G protein-gated inwardly rectifying K+ (GIRK/Kir3) channels are mainly expressed in excitable cells such as neurons and atrial myocytes, where they can respond to a wide variety of neurotransmitters. Four GIRK subunits have been found in mammals (GIRK1-4) and act as downstream targets for various Gαi/o-linked G protein-coupled receptors (GPCRs). Activation of GIRK channels produces a postsynaptic efflux of potassium from the cell, responsible for hyper-polarization/inhibition of the neuron. A growing body of evidence suggests that dysregulation of GIRK signalling can lead to excessive or deficient neuronal excitability, which contributes to neurological diseases and disorders. Therefore, GIRK channels are proposed as new pharmacological targets. The function of GIRK channels in neurons is not only determined by their biophysical properties but also by their cellular and subcellular localization patterns and densities on the neuronal surface. GIRK channels can be located within several subcellular compartments, where they have many different functional implications. This subcellular localization changes dynamically along the neuronal surface in response to drug intake and following plasticity processes. Ongoing research is focusing on determining the proteins that form macromolecular complexes with GIRK channels and are responsible for fast and precise signalling under physiological conditions, and how their alteration is implicated in pathological conditions. In this review, the distinct regional, cellular, and subcellular distribution of GIRK channel subunits in the brain will be discussed in view of their possible functional and pathological implications.
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    Relación entre la práctica deportiva en Clubes Deportivos y la mejora del control de la impulsividad en escolares
    (Universidad de Murcia. Servicio de publicaciones, 2021) Calleja Reina, Marina; Rueda Gómez, José Manuel; Barbosa Gonzalez, Antonio
    La práctica regular de Actividad Física Deportiva (en adelante AFD) tiene efectos beneficiosos a nivel físico y cognitivo. Trabajos recientes han encontrado influencia entre la práctica de AFD y la mejora en memoria, en rendimiento académico, en autoestima, en atención y en Funciones Ejecutivas.En el presente trabajo de corte comparativo han participado 110 estudiantes de Educación Primaria y de Educación Secundaria Obligatoria de las localidades de Ourense y Málaga, con edades comprendidas entre 8 y 14 años (M=10,89; DT=1,54). Los estudiantes se asignaron a diferentes grupos: estudiantes que practican AFD federados en clubes deportivos a nivel competitivo o AFD-F (n= 37), estudiantes que practican AFD en horario extraescolar en los centros educativos o AFD-C (n=37) y un grupo de estudiantes que no practicaban ningún tipo de AFD o No-AFD (n=36) Los resultados muestran la modulación de la AFD en diferentes modalidades de inhibición, comparando estudiantes que practican y los que no practican AFD (en línea con trabajos previos). Por otra parte, se ha analizado si la modalidad de AFD (AFD-F vs. AFD-C) contribuye al desarrollo diferencial de algunos componentes inhibitorios. Los resultados muestran que la AFD en ambos grupos (AFD-F y AFD-C) mejora el control atencional y el control inhibitorio, evidenciando similares resultados en la habilidad para cumplir las reglas, en la precisión en la búsqueda visual y en la flexibilidad cognitiva. Sin embargo, hemos encontrado que la práctica de AFD-F mejora los índices en el control de la impulsividad en comparación con la práctica de AFD-C.