32 resultados para Multiphasic
Resumo:
Cartilage tissue is a complex nonlinear, viscoelastic, anisotropic, and multiphasic material with a very low coefficient of friction, which allows to withstand millions of cycles of joint loading over decades of wear. Upon damage, cartilage tissue has a low self-reparative capacity due to the lack of neural connections, vascularization, and a latent pool of stem/chondroprogenitor cells. Therefore, the healing of articular cartilage defects remains a significant clinical challenge, affecting millions of people worldwide. A plethora of biomaterials have been proposed to fabricate devices for cartilage regeneration, assuming a wide range of forms and structures, such as sponges, hydrogels, capsules, fibers, and microparticles. In common, the fabricated devices were designed taking in consideration that to fully achieve the regeneration of functional cartilage it is mandatory a well-orchestrated interplay of biomechanical properties, unique hierarchical structures, extracellular matrix (ECM), and bioactive factors. In fact, the main challenge in cartilage tissue engineering is to design an engineered device able to mimic the highly organized zonal architecture of articular cartilage, specifically its spatiomechanical properties and ECM composition, while inducing chondrogenesis, either by the proliferation of chondrocytes or by stimulating the chondrogenic differentiation of stem/chondro-progenitor cells. In this chapter we present the recent advances in the development of innovative and complex biomaterials that fulfill the required structural key elements for cartilage regeneration. In particular, multiphasic, multiscale, multilayered, and hierarchical strategies composed by single or multiple biomaterials combined in a welldefined structure will be addressed. Those strategies include biomimetic scaffolds mimicking the structure of articular cartilage or engineered scaffolds as models of research to fully understand the biological mechanisms that influence the regeneration of cartilage tissue.
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The endocannabinoid system (ECS) is a construct based on the discovery of receptors that are modulated by the plant compound tetrahydrocannabinol and the subsequent identification of a family of nascent ligands, the 'endocannabinoids'. The function of the ECS is thus defined by modulation of these receptors-in particular, by two of the best-described ligands (2-arachidonyl glycerol and anandamide), and by their metabolic pathways. Endocannabinoids are released by cell stress, and promote both cell survival and death according to concentration. The ECS appears to shift the immune system towards a type 2 response, while maintaining a positive energy balance and reducing anxiety. It may therefore be important in resolution of injury and inflammation. Data suggest that the ECS could potentially modulate mitochondrial function by several different pathways; this may help explain its actions in the central nervous system. Dose-related control of mitochondrial function could therefore provide an insight into its role in health and disease, and why it might have its own pathology, and possibly, new therapeutic directions.
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The purpose of this study was to determine the degree to which the Big-Five personality taxonomy, as represented by the Minnesota Multiphasic Personality Inventory (MMPI), California Psychological Inventory (CPI), and Inwald Personality Inventory (IPI) scales, predicted a variety of police officer job performance criteria. Data were collected archivally for 270 sworn police officers from a large Southeastern municipality. Predictive data consisted of scores on the MMPI, CPI, and IPI scales as grouped in terms of the Big-Five factors. The overall score on the Wonderlic was included in order to assess criterion variance accounted for by cognitive ability. Additionally, a psychologist's overall rating of predicted job fit was utilized to assess the variance accounted for by a psychological interview. Criterion data consisted of supervisory ratings of overall job performance, State Examination scores, police academy grades, and termination. Based on the literature, it was hypothesized that officers who are higher on Extroversion, Conscientiousness, Agreeableness, Openness to Experience, and lower on Neuroticism, otherwise known as the Big-Five factors, would outperform their peers across a variety of job performance criteria. Additionally, it was hypothesized that police officers who are higher in cognitive ability and masculinity, and lower in mania would also outperform their counterparts. Results indicated that many of the Big-Five factors, namely, Neuroticism, Conscientiousness, Agreeableness, and Openness to Experience, were predictive of several of the job performance criteria. Such findings imply that the Big-Five is a useful predictor of police officer job performance. Study limitations and implications for future research are discussed. ^
Resumo:
Development of some immune-mediated disorders may depend on dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. To explore neuropsychologic mechanisms in relation to the abnormal endocrine reactivity in patients with systemic lupus erythematosus (SLE) and chronic hepatitis C (CHC) we used the corticotropin releasing hormone (CRH) test, the Minnesota Multiphasic Personality Inventory (MMPI), and the Edinburgh Inventory of Manual Preference Inventory (EIMP). Compared to controls, the adrenocorticotrophic hormone (ACTH) response to CRH was reduced in CHC, while SLE presented reduced baseline dehydroepiandrosterone sulfate levels; higher neurotic scores were found in SLE and higher behavior deviant scores in CHC. Peak ACTH levels were a significant factor for the MMPI profile variability, while the manual preference score was a significant factor for the ACTH response. Personality and manual preference contribute to neuroendocrine abnormalities. Different behavioral and neuroimmunoendocrine models emerge for these disorders.
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OBJECTIVE: - Clinical observations and a review of the literature led us to hypothesize that certain personality and character traits could provide improved understanding, and thus improved prevention, of suicidal behaviour among young women with eating disorders. METHOD: - The clinical group consisted of 152 women aged between 18 and 24 years, with DSM-IV anorexia nervosa/restrictive type (AN-R = 66), anorexia nervosa/purging type (AN-P = 37), bulimia nervosa/non-purging type (BN-NP = 9), or bulimia nervosa/purging type (BN-P = 40). The control group consisted of 140 subjects. The assessment measures were the Minnesota Multiphasic Personality Inventory-second version (MMPI-2) scales and subscales, the Beck Depression Inventory (BDI) used to control for current depressive symptoms, plus a specific questionnaire concerning suicide attempts. RESULTS: - Suicide attempts were most frequent in subjects with purging behaviour (30.0% for BN-P and 29.7% for AN-P). Those attempting suicide among subjects with eating disorders were mostly students (67.8%). For women with AN-R the scales for 'Depression' and 'Antisocial practices' represented significant suicidal risk, for women with AN-P the scales for 'Hysteria', 'Psychopathic deviate', 'Shyness/Self-consciousness', 'Antisocial Practices', 'Obsessiveness' and 'Low self-esteem' were risk indicators and for women with BN-P the 'Psychasthenia', 'Anger' and 'Fears' scales were risk indicators. CONCLUSION: - This study provides interesting results concerning the personality traits of young women with both eating disorders and suicidal behaviour. Students and those with purging behaviour are most at risk. Young women should be given more attention with regard to the risk of suicide attempts if they: (a). have AN-R with a tendency to self-punishment and antisocial conduct, (b). have AN-P with multiple physical complaints, are not at ease in social situations and have antisocial behaviour, or (c). if they have BN-P and tend to be easily angered with obsessive behaviour and phobic worries. The MMPI-2 is an interesting assessment method for the study of traits indicating a risk of suicidal behaviour in young subjects, after controlling for current depressive pathology.
Resumo:
The main aim of this study was to replicate and extend previous results on subtypes of adolescents with substance use disorders (SUD), according to their Minnesota Multiphasic Personality Inventory for adolescents (MMPI-A) profiles. Sixty patients with SUD and psychiatric comorbidity (41.7% male, mean age = 15.9 years old) completed the MMPI-A, the Teen Addiction Severity Index (T-ASI), the Child Behaviour Checklist (CBCL), and were interviewed in order to determine DSMIV diagnoses and level of substance use. Mean MMPI-A personality profile showed moderate peaks in Psychopathic Deviate, Depression and Hysteria scales. Hierarchical cluster analysis revealed four profiles (acting-out, 35% of the sample; disorganized-conflictive, 15%; normative-impulsive, 15%; and deceptive-concealed, 35%). External correlates were found between cluster 1, CBCL externalizing symptoms at a clinical level and conduct disorders, and between cluster 2 and mixed CBCL internalized/externalized symptoms at a clinical level. Discriminant analysis showed that Depression, Psychopathic Deviate and Psychasthenia MMPI-A scales correctly classified 90% of the patients into the clusters obtained.
Resumo:
The main aim of this study was to replicate and extend previous results on subtypes of adolescents with substance use disorders (SUD), according to their Minnesota Multiphasic Personality Inventory for adolescents (MMPI-A) profiles. Sixty patients with SUD and psychiatric comorbidity (41.7% male, mean age = 15.9 years old) completed the MMPI-A, the Teen Addiction Severity Index (T-ASI), the Child Behaviour Checklist (CBCL), and were interviewed in order to determine DSMIV diagnoses and level of substance use. Mean MMPI-A personality profile showed moderate peaks in Psychopathic Deviate, Depression and Hysteria scales. Hierarchical cluster analysis revealed four profiles (acting-out, 35% of the sample; disorganized-conflictive, 15%; normative-impulsive, 15%; and deceptive-concealed, 35%). External correlates were found between cluster 1, CBCL externalizing symptoms at a clinical level and conduct disorders, and between cluster 2 and mixed CBCL internalized/externalized symptoms at a clinical level. Discriminant analysis showed that Depression, Psychopathic Deviate and Psychasthenia MMPI-A scales correctly classified 90% of the patients into the clusters obtained.
Resumo:
The EEG of the sleep onset period of psychophysiological insomniacs, psychiatric insomniacs and controls was compared using power spectral analysis (FFT). Eighteen drug-free subjects were equally divided into three groups according to their responses in the Brock Sleep and Insomnia Questionnaire, the Minnesota Multiphasic Personality Inventory and the Sleep Disorders Questionnaire. Group 1 consisted of psychophysiological insomniacs, group 2 included insomniacs with an indication of psychiatric disturbances, and group 3 was a control group. EEG, EOG and EMG were recorded for two consecutive nights. Power spectral analysis (FFT) of EEG at C4 from the sleep onset period (defined as lights out to the first five minutes of stage 2) was performed on all standard frequency bands, delta: .5-4 Hz; theta: 4-8 Hz; alpha: 8-12 Hz; sigma: 12-15 Hz beta: 15-25 Hz. Psychophysiological insomniacs had less alpha during wakefulness than the other two groups and did not show the dramatic drop in alpha across the sleep onset period, which characterizes normal sleep. They also had less delta, especially during stage 2 on night 2. They also showed less delta in the last quartile of the chronological analysis of the sleep onset period. Psychiatric insomniacs showed lower relative beta power values overall while psychophysiological insomniacs showed higher relative beta power values during wakefulness. This microanalysis 11 confirms that the sleep onset period is generally similar for psychiatric insomniacs and normal sleepers. This may be due to the sample of psychiatric insomniacs being heterogeneous or may reflect a sleep onset system that is essentially intact. Psychophysiological insomniacs have higher cortical arousal during the sleep onset period than do the psychiatric insomniacs and the controls. Clear differences in the sleep onset period of psychophysiological insomniacs exist. The dramatic changes in power values in these two groups are not seen in the psychophysiological insomniacs, which may make the discrimination between wakefulness and sleep more difficult.
Resumo:
El neurofeedback es una técnica no invasiva en la que se pretende corregir, mediante condicionamiento operante, ondas cerebrales que se encuentren alteradas en el electroencefalograma. Desde 1967, se han conducido numerosas investigaciones relacionadas con los efectos de la técnica en el tratamiento de alteraciones psicológicas. Sin embargo, a la fecha no existen revisiones sistemáticas que reúnan los temas que serán aquí tratados. El aporte de este trabajo es la revisión de 56 artículos, publicados entre los años 1995 y 2013 y la evaluación metodológica de 29 estudios incluidos en la revisión. La búsqueda fue acotada a la efectividad del neurofeedback en el tratamiento de depresión, ansiedad, trastorno obsesivo compulsivo (TOC), ira y fibromialgia. Los hallazgos demuestran que el neurofeedback ha tenido resultados positivos en el tratamiento de estos trastornos, sin embargo, es una técnica que aún está en desarrollo, con unas bases teóricas no muy bien establecidas y cuyos resultados necesitan de diseños metodológicamente más sólidos que ratifiquen su validez.
Resumo:
Determinar los elementos que constituyen una conducta social. Determinar como se relacionan determinados aspectos de una conducta para producir una conducta social habilidosa.. 10 sujetos entre 18 y 30 años con nivel socio-cultural medio-alto y problemas de incorporación social.. Entrevista y evaluación en tres areas: ansiedad social, cognisciones y actuación propia. EMES_M, AI, SAD, FNE.. Entrevista de Arkowitz, 1981, Minnesota Multiphasic Personality Inventory, Sixteen Personality Factor Questionnaire, State-Trait Anxiety Inventory Beck Depression Inventary.. Gráficos de barras y circulares, tablas.. Los resultados se presentan a modo de gráficos. Existen vinculaciones dadas como significativas a través de un porcentaje que vincula un test a un aspecto de la personalidad, sin una más amplia definición.. Prueba básicamente empírica que engloba los resultados anteriores y posteriores a un adiestramiento en 'habilidades sociales'. Cualquier cuestionario es desglosado en función de los resultados significativos obtenidos en cada test..
Resumo:
Estudiar los factores de la personalidad mediante un estudio experimental. 141 sujetos de Las Palmas, 79 son chicas y 62 chicos. Todos realizan estudios en centros estatales de ense??anza media, en los cursos de COU, tercero y segundo de BUP. Ofrece unos presupuestos te??ricos centrados en la teor??a factorialista de Cattell y su af??n de estudiar cient??ficamente la personalidad, m??s una breve exposici??n de la nomenclatura y de la utilidad que tienen los dos tests que va a utilizar en el estudio experimental. Despu??s explica en qu?? consiste dicho estudio y concluye con los resultados obtenidos en un estudio de casos. Cuestionarios Hight School Personality Questionnaire (HSPQ) y Minnesota Multiphasic Personality Inventory (MMPI). Se aplican las pruebas HSPQ y MMPI y despu??s se analizan los resultados hallando la media del grupo femenino y la del masculino para obtener las diferencias existentes en la personalidad de ambos grupos. Para obtener mayor informaci??n sobre las dimensiones de la personalidad se realiza un estudio de casos. 1) En los resultados generales de grupo se deduce que: a) En las chicas se da una mayor sensibilidad e impaciencia, con ciertos sentimientos de inseguridad, reflejando sus problemas psicol??gicos a trav??s de la somatizaci??n; b) Los chicos poseen una mayor estabilidad emocional, son m??s dominantes y competitivos, dados a la acci??n y m??s resueltos en sus decisiones, aunque no se valoran en sus aut??nticas posibilidades. Mientras que los resultados en el estudio de casos: a) El perfil del sujeto femenino destaca por su gran iniciativa, optimismo, decisi??n, sociabilidad y no se encuentra atada por las costumbres sociales que le rodean, mostr??ndose rebelde con la autoridad, inconforme con el ambiente, agresiva e individualista. Adem??s presenta un Yo fuerte, estable, con ausencia de depresiones y con una normal preocupaci??n por la salud; b) El perfil masculino demuestra un sujeto acogedor y dispuesto a la cooperaci??n, con inteligencia general algo superior a la media. Tiene una considerable fuerza del Yo, es emocionalmente maduro y estable y con un temperamento bastante reflexivo. Pero presenta cierta dependencia del grupo y la b??squeda de aprobaci??n por un lado, y el deseo de autosuficiencia por otro. 1) La aplicaci??n del HSPQ ha permitido, por la asociaci??n con las escalas del MMPI, orientar de alguna manera las posibilidades cl??nicas de descripci??n de los factores de Cattell, a pesar de ser un test encaminado, m??s bien, a detectar la personalidad en sus formulaciones positivas de equilibrio y madurez. 2) Se confirma la orientaci??n bipolar de los factores del HSPQ, con las correlaciones positivas o negativas con el MMPI; al mismo tiempo que se apoyan o refutan las orientaciones positivas y negativas, respecto de la personalidad. 3) Igualmente en el MMPI, a trav??s de las correlaciones y sobre todo por medio del an??lisis factorial, se ha podido comprobar, c??mo no existe una enfermedad o desviaci??n psicopatol??gica por antonomasia, sino que se forma un conglomerado con todas ellas, aunque llevan un matiz definido.
Resumo:
Estudiar la personalidad. 296 sujetos de Gijón, 191 son universitarios masculinos y 105 alumnas de sexto de bachillerato femenino. Expone unos presupuestos generales sobre la personalidad, analiza las teorías acerca de la misma, estudia científicamente la personalidad a través de la teoría de R.B. Cattell y de su cuestionario (HSPQ), y explica en qué consiste el Minnesota Multiphasic Personality Inventory (MMPI). Después realiza un trabajo experimental sobre la personalidad aplicando las pruebas citadas a estudiantes de Gijón. High School Personality Questionnaire (HSPQ) y Minnesota Multiphasic Personality Inventory (MMPI). La aplicación del HSPQ permite, por la asociación con las escalas de MMPI, comprobar de alguna manera las posibilidades clínicas de descripción de los factores de Cattell. 1) La histeria se da más en la muestra femenina, mientras que la psicastenia abunda en mayor medida en la masculina. 2) En la inteligencia, hay mayor dispersión entre los hombres, y hay mayor concentración sobre una media superior en las mujeres. 3) La estabilidad emocional favorece a las mujeres, mientras que la tensión aprensiva y la autosuficiencia destacan en los hombres. 1) El análisis factorial que se ha realizado sobre las variables de Cattell ha confirmado la línea de factores y de agrupaciones factoriales en notas de personalidad tal como las recoge, esencialmente, el manual. 2) Se ve confirmada la orientación bipolar de los factores HSPQ con las correlaciones positivas o negativas con el MMPI, al mismo tiempo que se destacan las orientaciones positivas o negativas, respecto de la personalidad, de las puntuaciones altas obtenidas en los diversos factores.
Resumo:
Suppression of depolarizing postsynaptic potentials and isolated GABA-A receptor-mediated fast inhibitory postsynaptic potentials by the muscarinic acetylcholine receptor agonist, oxotremorine-M (10 microM), was investigated in adult and immature (P14-P30) rat piriform cortical (PC) slices using intracellular recording. Depolarizing postsynaptic potentials evoked by layers II-III stimulation underwent concentration-dependent inhibition in oxotremorine-M that was most likely presynaptic and M2 muscarinic acetylcholine receptor-mediated in immature, but M1-mediated in adult (P40-P80) slices; percentage inhibition was smaller in immature than in adult piriform cortex. In contrast, compared with adults, layer Ia-evoked depolarizing postsynaptic potentials in immature piriform cortex slices in oxotremorine-M, showed a prolonged multiphasic depolarization with superimposed fast transients and spikes, and an increased 'all-or-nothing' character. Isolated N-methyl-d-aspartate receptor-mediated layer Ia depolarizing postsynaptic potentials (although significantly larger in immature slices) were however, unaffected by oxotremorine-M, but blocked by dl-2-amino-5-phosphonovaleric acid. Fast inhibitory postsynaptic potentials evoked by layer Ib or layers II-III-fiber stimulation in immature slices were significantly smaller than in adults, despite similar estimated mean reversal potentials ( approximately -69 and -70 mV respectively). In oxotremorine-M, only layer Ib-fast inhibitory postsynaptic potentials were suppressed; suppression was again most likely presynaptic M2-mediated in immature slices, but M1-mediated in adults. The degree of fast inhibitory postsynaptic potential suppression was however, greater in immature than in adult piriform cortex. Our results demonstrate some important physiological and pharmacological differences between excitatory and inhibitory synaptic systems in adult and immature piriform cortex that could contribute toward the increased susceptibility of this region to muscarinic agonist-induced epileptiform activity in immature brain slices.
Resumo:
One of the most studied ceramic superconductors for application has been, undoubtedly, Bi2Sr2CaCu2O8+delta. Although being a multiphasic material, it has proved to have great advantages compared to other ceramic systems. Measurements of the elastic energy loss and modulus (anelastic spectroscopy) as a function of temperature call distinguish among different atomic jumps that occur inside the various phases or at different local ordering. In this paper, mechanical loss spectra of Bi2Sr2CaCu2O8+delta bar shaped samples, made by a conventional method, have been measured between 80 and 600 K, using a torsion pendulum operating in frequencies below 50 Hz, for samples annealed in vacuum up to 600 K. Possible relaxation mechanisms are proposed to explain the origin of the mechanical-loss peaks observed 300 and 500 K. (C) 2004 Elsevier B.V. All rights reserved.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)