Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
1.
Acta Psychiatr Scand ; 142(1): 27-39, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31953847

RESUMEN

This article discusses initiatives aimed at preventing and reducing 'coercive practices' in mental health and community settings worldwide, including in hospitals in high-income countries, and in family homes and rural communities in low- and middle-income countries. The article provides a scoping review of the current state of English-language empirical research. It identifies several promising opportunities for improving responses that promote support based on individuals' rights, will and preferences. It also points out several gaps in research and practice (including, importantly, a gap in reviews of non-English-language studies). Overall, many studies suggest that efforts to prevent and reduce coercion appear to be effective. However, no jurisdiction appears to have combined the full suite of laws, policies and practices which are available, and which taken together might further the goal of eliminating coercion.


Asunto(s)
Coerción , Lenguaje , Servicios de Salud Mental/ética , Humanos , Salud Mental
2.
Eur Psychiatry ; 44: 24-29, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28535407

RESUMEN

BACKGROUND: The weak regulation, or "dysregulation", of the Behavioural Activation System (BAS) is implicated in the development and recurrence of bipolar disorder. However, there has been a lack of prospective studies investigating the predictive role of BAS dysregulation in relation to bipolar-vulnerability. Furthermore, no studies have tested the prospective predictive utility of the DYS self-report measure of BAS dysregulation in an analogue sample. The goal of the current study was to redress this gap. METHODS: Participants (n=127) completed baseline self-report measures of mood symptoms (Internal States Scale [ISS]), the Hypomanic Personality Scale (HPS), behavioural activation, inhibition and dysregulation of BAS (BIS/BAS and DYS), and at six months, the Mood Disorders Questionnaire (MDQ). RESULTS: Linear regression analysis indicated a significant main effect of BAS Dysregulation, and a significant interaction between BIS and BAS Fun Seeking, on prospective MDQ scores whilst controlling for baseline mood symptoms and HPS scores. The interaction effect indicated that the relationship between high BAS Fun Seeking and follow-up MDQ scores was strongest when BIS scores were high, whilst the lowest MDQ scores were observed for a combination of low BAS Fun Seeking and high BIS. However, DYS scores were the stronger predictor of MDQ scores compared to the BAS Fun Seeking and BIS interaction. CONCLUSIONS: Bipolar-vulnerability is prospectively associated with heightened BAS Dysregulation, as measured by the DYS subscale, similar to prior findings in clinical samples. Further research investigating the longer-term associations between BAS Dysregulation with the development of clinically significant bipolar mood symptoms is required.


Asunto(s)
Afecto , Trastorno Bipolar/psicología , Inhibición Psicológica , Adulto , Trastorno Ciclotímico/psicología , Femenino , Humanos , Masculino , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Autoinforme , Encuestas y Cuestionarios
3.
Clin Psychol Rev ; 54: 1-16, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28371648

RESUMEN

We sought to conduct the first systematic review of empirical evidence investigating the role of psychological factors in the relationship between sleep problems and suicidal thoughts and behaviours. Twelve studies were identified which examined psychological factors grouped into four categories of cognitive appraisals, psychosocial factors, emotion regulation strategies, and risk behaviours. Although there was substantial heterogeneity across studies with respect to measurement, sampling, and analysis, preliminary evidence indicated that negative cognitive appraisals, perceived social isolation, and unhelpful emotion regulation strategies may contribute to the association between sleep problems and suicidal thoughts and behaviours. Given that findings in this area are currently restricted to studies with cross-sectional designs, the directionality of the interrelationships between these psychological factors, sleep problems and suicidality, remains unclear. We integrate the findings of our review with contemporary psychological models of suicidal behaviour to develop a clear research agenda. Identified pathways should now be tested with longitudinal and experimental designs. In addition, a more thorough investigation of the complexities of sleep, psychological factors, and suicidal thoughts and behaviours is crucial for the development of targeted psychological interventions.


Asunto(s)
Trastornos del Sueño-Vigilia/psicología , Ideación Suicida , Intento de Suicidio/psicología , Suicidio/psicología , Humanos , Asunción de Riesgos
4.
Eur Psychiatry ; 30(8): 988-94, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26497469

RESUMEN

BACKGROUND: Research is sparse which examines pathways to suicide, and resilience to suicide, in people who are particularly vulnerable to suicide, for example, prison inmates. The purpose of this study was to examine the ways in which perceptions of self-esteem and coping ability interacted with defeat and entrapment to both amplify suicidal thoughts and feelings, and to act as a buffer against suicidal thoughts and feelings. METHODS: Participants were 65 male prisoners at high risk of suicide. A cross-sectional questionnaire design was used. Questionnaire measures of depression, defeat, entrapment, self-esteem, coping ability and suicidal probability were administered. RESULTS: For the hopelessness component of the suicide probability measure, high levels of coping ability together with low levels of defeat resulted in the lowest levels of suicidality indicative of a resilience factor. In contrast, low levels of coping skills together with high levels of entrapment were a high risk factor for this hopelessness component of suicide. This pattern of results pertained when controlling for depression levels. CONCLUSIONS: This is the first study to examine interactions between defeat, entrapment and appraisals of self-esteem and coping ability. Therapeutic interventions would benefit from boosting perceptions and appraisals of coping ability, in particular, in people who are at high risk for suicide.


Asunto(s)
Adaptación Psicológica , Depresión/psicología , Prisioneros/psicología , Resiliencia Psicológica , Autoimagen , Prevención del Suicidio , Suicidio , Adulto , Estudios Transversales , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo/métodos , Factores de Riesgo , Autoevaluación (Psicología) , Ideación Suicida , Suicidio/psicología , Encuestas y Cuestionarios , Reino Unido
5.
Psychol Med ; 45(16): 3441-51, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26165919

RESUMEN

BACKGROUND: Prisoners have an exceptional risk of suicide. Cognitive-behavioural therapy for suicidal behaviour has been shown to offer considerable potential, but has yet to be formally evaluated within prisons. This study investigated the feasibility of delivering and evaluating a novel, manualized cognitive-behavioural suicide prevention (CBSP) therapy for suicidal male prisoners. METHOD: A pilot randomized controlled trial of CBSP in addition to treatment as usual (CBSP; n = 31) compared with treatment as usual (TAU; n = 31) alone was conducted in a male prison in England. The primary outcome was self-injurious behaviour occurring within the past 6 months. Secondary outcomes were dimensions of suicidal ideation, psychiatric symptomatology, personality dysfunction and psychological determinants of suicide, including depression and hopelessness. The trial was prospectively registered (number ISRCTN59909209). RESULTS: Relative to TAU, participants receiving CBSP therapy achieved a significantly greater reduction in suicidal behaviours with a moderate treatment effect [Cohen's d = -0.72, 95% confidence interval -1.71 to 0.09; baseline mean TAU: 1.39 (S.D. = 3.28) v. CBSP: 1.06 (S.D. = 2.10), 6 months mean TAU: 1.48 (S.D. = 3.23) v. CBSP: 0.58 (S.D. = 1.52)]. Significant improvements were achieved on measures of psychiatric symptomatology and personality dysfunction. Improvements on psychological determinants of suicide were non-significant. More than half of the participants in the CBSP group achieved a clinically significant recovery by the end of therapy, compared with a quarter of the TAU group. CONCLUSIONS: The delivery and evaluation of CBSP therapy within a prison is feasible. CBSP therapy offers significant promise in the prevention of prison suicide and an adequately powered randomized controlled trial is warranted.


Asunto(s)
Terapia Cognitivo-Conductual/métodos , Depresión/terapia , Cooperación del Paciente , Prisioneros/psicología , Prevención del Suicidio , Adulto , Afecto , Atención , Cognición , Inglaterra , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Solución de Problemas , Escalas de Valoración Psiquiátrica , Autoimagen , Autoinforme , Resultado del Tratamiento , Adulto Joven
6.
Compr Psychiatry ; 55(1): 104-12, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23972619

RESUMEN

BACKGROUND: A growing body of research has highlighted the importance of identifying resilience factors against suicidal behavior. However, no previous study has investigated potential resilience factors among individuals with Posttraumatic Stress Disorder (PTSD). The aim of this study was to examine whether perceived social support buffered the impact of PTSD symptoms on suicidal behavior. METHODS: Fifty-six individuals who had previously been exposed to a traumatic event and reported PTSD symptoms in the past month (n = 34, 60.7% participants met the full criteria for a current PTSD diagnosis) completed a range of self-report measures assessing PTSD symptoms, perceived social support and suicidal behavior. Hierarchical regression analyses were conducted to examine whether perceived social support moderates the effects of PTSD symptoms on suicidal behavior. RESULTS: The results showed that perceived social support moderated the impact of the number and severity of PTSD symptoms on suicidal behavior. For those who perceived themselves as having high levels of social support, an increased number and severity of PTSD symptoms were less likely to lead to suicidal behavior. CONCLUSIONS: The current findings suggest that perceived social support might confer resilience to individuals with PTSD and counter the development of suicidal thoughts and behaviors. The milieu of social support potentially provides an area of further research and an important aspect to incorporate into clinical interventions for suicidal behavior in PTSD or trauma populations.


Asunto(s)
Resiliencia Psicológica , Apoyo Social , Trastornos por Estrés Postraumático/psicología , Ideación Suicida , Intento de Suicidio/psicología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Índice de Severidad de la Enfermedad
7.
Crisis ; 34(4): 273-81, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23608231

RESUMEN

BACKGROUND: Suicide has been conceived as involving a continuum, whereby suicidal plans and acts emerge from thoughts about suicide. Suicide prevention strategies need to determine whether different responses are needed at these points on the continuum. AIMS: This study investigates factors that were perceived to counter suicidal ideation, plans, and acts. METHOD: The 36 participants, all of whom had had experiences of psychosis and some level of suicidality, were presented with a vignette describing a protagonist with psychotic symptoms. They were asked to indicate what would counter the suicidal thoughts, plans, and acts of the protagonist described in the vignette. Qualitative techniques were first used to code these free responses into themes/categories. Correspondence analysis was then applied to the frequency of responses in each of these categories. RESULTS: Social support was identified as a strong counter to suicidal ideation but not as a counter to suicidal plans or acts. Help from health professionals was strongly related to the cessation of suicidal plans as were the opinions of the protagonist's children. Changing cognitions and strengthening psychological resources were more weakly associated with the cessation of suicidal ideation and plans. The protagonist's children were considered potentially helpful in addressing suicidal acts. CONCLUSION: These results suggest that both overlapping and nonoverlapping factors need to be considered in understanding suicide prevention, dependent on whether individuals are thinking about, planning, or attempting suicide.


Asunto(s)
Actitud Frente a la Salud , Servicios de Salud Mental , Trastornos Psicóticos/psicología , Apoyo Social , Ideación Suicida , Suicidio/psicología , Adolescente , Adulto , Trastornos Psicóticos Afectivos/psicología , Anciano , Trastorno Bipolar/psicología , Trastorno Depresivo/psicología , Femenino , Esperanza , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Factores de Riesgo , Esquizofrenia , Psicología del Esquizofrénico , Intento de Suicidio/prevención & control , Intento de Suicidio/psicología , Adulto Joven , Prevención del Suicidio
8.
Behav Res Ther ; 50(10): 589-95, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22835839

RESUMEN

The broaden-and-build theory postulates that positive emotions broaden people's cognitions and actions, and facilitate the building of personal and social resources which enhance resilience in a range of clinical populations. The Broad-Minded Affective Coping procedure (BMAC) is a recently developed clinical technique which utilizes the recall of positive autobiographical memories and mental imagery to elicit positive affect. This study aims to investigate the ability of the BMAC to boost mood among 50 individuals diagnosed currently (n = 31) or previously (n = 19) with Posttraumatic Stress Disorder (PTSD). To assess mood, a series of Visual Analog Scales (VASs) and Likert scales measuring feelings of sadness, calmness, happiness, hopelessness, defeat and frustration were administrated at baseline, immediately following the completion of the BMAC and two hours and two days afterwards. Participants in the BMAC condition demonstrated greater increases in self-reported levels of positive emotions and greater reductions in self-reported levels of negative emotions following the BMAC technique compared to those in the control condition. The results suggest that the BMAC is a useful clinical technique which can be incorporated into other clinical interventions such as cognitive behavioral therapy to elicit positive affect and promote resilience.


Asunto(s)
Adaptación Psicológica , Afecto , Imágenes en Psicoterapia/métodos , Trastornos por Estrés Postraumático/terapia , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Recuerdo Mental , Persona de Mediana Edad , Trastornos por Estrés Postraumático/psicología , Adulto Joven
9.
Br J Clin Psychol ; 51(1): 72-83, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22268542

RESUMEN

OBJECTIVE: There is a suggestion in the literature that more variable affect increases suicidal ideation through the repeated re-activation of latent suicidal cognitions. The hypothesis that affective variability would be a better predictor of suicidal ideation and related behaviour than affect level was tested in individuals at ultra-high risk of developing psychosis. This study also examined the prediction that affective variability is a suicide-specific mechanism and would not predict levels of attenuated psychotic phenomena. METHOD: Twenty-seven ultra-high risk individuals were required to complete ambulant ratings of their affect when prompted by an electronic wristwatch for six days (the experience sampling method). In the debriefing session, participants were assessed with a semi-structured interview (the Comprehensive Assessment of At-Risk Mental State), which assessed the severity and frequency of suicidality and psychosis-related phenomena. RESULTS: The variability of negative and positive affect was predictive of the frequency of suicidal thoughts and behaviour. More variable negative, but not positive affect, was also associated with more severe suicidal ideation and related behaviour. Affect variability was not significantly related to the severity of attenuated psychotic phenomena. CONCLUSION: Affective variability appears to be a specific risk factor for suicidal ideation in individuals at ultra-high risk of developing psychosis. Early intervention should focus on providing individuals with skills for regulating their own affect.


Asunto(s)
Afecto , Trastornos Psicóticos/psicología , Ideación Suicida , Adulto , Femenino , Humanos , Entrevista Psicológica , Masculino , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Adulto Joven
10.
Int J Geriatr Psychiatry ; 27(3): 262-70, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21472780

RESUMEN

BACKGROUND: The goal of the current study was to investigate psychological resilience in the older adults (>64 years) compared with that of the young ones (<26 years). METHODS: Questionnaire measures of depression, hopelessness, general health and resilience were administered to the participants. The resilience measure comprised three sub-scales of social support, emotional regulation and problem solving. RESULTS: The older adults were the more resilient group especially with respect to emotional regulation ability and problem solving. The young ones had more resilience related to social support. Poor perceptions of general health and low energy levels predicted low levels of resilience regardless of age. Low hopelessness scores also predicted greater resilience in both groups. Experiencing higher levels of mental illness and physical dysfunction predicted high resilience scores especially for the social support resilience scale in the older adults. The negative effects of depression on resilience related to emotional regulation were countered by low hopelessness but only in the young adults. CONCLUSIONS: These results highlight the importance of maintaining resilience-related coping skills in both young and older adults but indicate that different psychological processes underlie resilience across the lifespan.


Asunto(s)
Envejecimiento/psicología , Resiliencia Psicológica , Adulto , Anciano , Estudios Transversales , Depresión/diagnóstico , Emociones , Femenino , Evaluación Geriátrica , Estado de Salud , Humanos , Masculino , Solución de Problemas , Análisis de Regresión , Autoeficacia , Apoyo Social , Encuestas y Cuestionarios , Reino Unido , Adulto Joven
11.
J Psychiatr Ment Health Nurs ; 19(2): 162-73, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22070759

RESUMEN

Attitudes about family interventions have been identified as a possible reason for the poor implementation of such treatments. The current study used Q methodology to investigate the attitudes of relatives of forensic service users and clinical staff towards family interventions in medium secure forensic units, particularly when facilitated by a web camera. Eighteen relatives and twenty-nine staff completed a sixty-one item Q sort to obtain their idiosyncratic views about family intervention. The results indicated that relatives and staff mostly held positive attitudes towards family intervention. Relatives showed some uncertainty towards family intervention that may reflect the lack of involvement they receive from the forensic service. Staff highlighted key barriers to successful implementation such as lack of dedicated staff time for family work and few staff adequately trained in family intervention. Despite agreement with the web-based forensic family intervention technique and its benefits, both staff and relatives predicted problems in the technique.


Asunto(s)
Actitud del Personal de Salud , Terapia Familiar , Familia/psicología , Psiquiatría Forense , Cuerpo Médico/psicología , Servicios de Salud Mental/organización & administración , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esquizofrenia/terapia
12.
Behav Res Ther ; 48(9): 883-9, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20538264

RESUMEN

Recent years have seen growing interest into concepts of resilience, but minimal research has explored resilience to suicide and none has investigated resilience to suicide amongst clinical groups. The current study aimed to examine whether a proposed resilience factor, positive self-appraisals of the ability to cope with emotions, difficult situations and the ability to gain social support, could buffer against the negative impact of hopelessness amongst individuals with psychosis-spectrum disorders when measured cross-sectionally. Seventy-seven participants with schizophrenia-spectrum disorders completed self-report measures of suicidal ideation, hopelessness and positive self-appraisals. Positive self-appraisals were found to moderate the association between hopelessness and suicidal ideation. For those reporting high levels of positive self-appraisals, increased levels of hopelessness were significantly less likely to lead to suicidality. These results provide cross-sectional evidence suggest that positive self-appraisals may buffer individuals with psychosis against the pernicious impact of a well known clinical risk factor, hopelessness. Accounting for positive self-appraisals may improve identification of individuals at high risk of suicidality, and may be an important area to target for suicide interventions.


Asunto(s)
Psicoterapia/métodos , Trastornos Psicóticos/psicología , Resiliencia Psicológica , Esquizofrenia/terapia , Ideación Suicida , Suicidio/psicología , Adaptación Psicológica , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trastornos Psicóticos/terapia , Refuerzo en Psicología , Psicología del Esquizofrénico , Autoimagen , Autoevaluación (Psicología) , Prevención del Suicidio
13.
Behav Res Ther ; 48(3): 179-86, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19906364

RESUMEN

AIMS: The Schematic Appraisals Model of Suicide (SAMS) suggests that positive self-appraisals may be important for buffering suicidal thoughts and behaviours, potentially providing a key source of resilience. The current study aimed to explore whether positive self-appraisals buffered individuals from suicidality in the face of stressful life events. METHOD: 78 participants who reported experiencing some degree of suicidality were recruited from a student population. They completed a battery of questionnaires including measures of suicidality, stressful life events and positive self-appraisals. RESULTS: Positive self-appraisals moderated the association between stressful life events and suicidality. For those reporting moderate or high levels of positive self-appraisals, raised incidence of stressful life events did not lead to increases in suicidality. DISCUSSION: These results support the SAMS framework, and suggest that positive self-appraisals may confer resilience to suicide. Positive self-appraisals may be a promising avenue for further resilience research, and an important area to target for suicide interventions.


Asunto(s)
Adaptación Psicológica , Modelos Psicológicos , Autoimagen , Suicidio/psicología , Femenino , Humanos , Masculino , Análisis de Regresión , Estrés Psicológico , Encuestas y Cuestionarios , Adulto Joven
14.
Neuropsychologia ; 43(4): 583-7, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15716148

RESUMEN

Baddeley and Wilson [Baddeley, A. D., & Wilson, F. B. (2002). Prose recall and amnesia: implications for the structure of working memory. Neuropsychologia 40, 1737-1743.] have argued that their finding of a positive association between amnesics' immediate prose recall scores and their scores on measures of executive function and fluid intelligence supports the view that an episodic buffer exists. However, the pattern of data from amnesics tested in our laboratory presented some problems for this conceptualisation of the episodic buffer.


Asunto(s)
Amnesia/fisiopatología , Lenguaje , Recuerdo Mental , Adulto , Femenino , Humanos , Inteligencia , Masculino , Procesos Mentales , Persona de Mediana Edad , Reconocimiento en Psicología
15.
Planta ; 213(5): 748-57, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11678279

RESUMEN

Polyphenol oxidase (PPO; EC 1.10.3.2) is the enzyme thought to be responsible for browning in banana [Musa cavendishii (AAA group, Cavendish subgroup) cv. Williams] fruit. Banana flesh was high in PPO activity throughout growth and ripening. Peel showed high levels of activity early in development but activity declined until ripening started and then remained constant. PPO activity in fruit was not substantially induced after wounding or treatment with 5-methyl jasmonate. Banana flowers and unexpanded leaf roll had high PPO activities with lower activities observed in mature leaves, roots and stem. Four different PPO cDNA clones were amplified from banana fruit (BPO1, BPO11, BPO34 and BPO35). Full-length cDNA and genomic clones were isolated for the most abundant sequence (BPO1) and the genomic clone was found to contain an 85-bp intron. Introns have not been previously found in PPO genes. Northern analysis revealed the presence of BPO1 mRNA in banana flesh early in development but little BPO1 mRNA was detected at the same stage in banana peel. BPO11 transcript was only detected in very young flesh and there was no detectable expression of BPO34 or BPO35 in developing fruit samples. PPO transcripts were also low throughout ripening in both flesh and peel. BPO1 transcripts were readily detected in flowers, stem, roots and leaf roll samples but were not detected in mature leaves. BPO11 showed a similar pattern of expression to BPO1 in these tissues but transcript levels were much lower. BPO34 and BPO35 mRNAs were only detected at a low level in flowers and roots and BPO34 transcript was detected in mature leaves, the only clone to do so. The results suggest that browning of banana fruit during ripening results from release of pre-existing PPO enzyme, which is synthesised very early in fruit development.


Asunto(s)
Catecol Oxidasa/genética , Frutas/genética , Musa/genética , Acetatos/farmacología , Secuencia de Bases , Catecol Oxidasa/efectos de los fármacos , Catecol Oxidasa/metabolismo , Clonación Molecular , Ciclopentanos/farmacología , ADN Complementario/química , ADN Complementario/genética , ADN de Plantas/genética , Frutas/enzimología , Frutas/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica , Regulación Enzimológica de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Intrones , Datos de Secuencia Molecular , Musa/enzimología , Musa/crecimiento & desarrollo , Oxilipinas , Reguladores del Crecimiento de las Plantas/farmacología , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN
16.
Plant J ; 27(6): 581-90, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11576441

RESUMEN

Post-transcriptional silencing of plant genes using anti-sense or co-suppression constructs usually results in only a modest proportion of silenced individuals. Recent work has demonstrated the potential for constructs encoding self-complementary 'hairpin' RNA (hpRNA) to efficiently silence genes. In this study we examine design rules for efficient gene silencing, in terms of both the proportion of independent transgenic plants showing silencing, and the degree of silencing. Using hpRNA constructs containing sense/anti-sense arms ranging from 98 to 853 nt gave efficient silencing in a wide range of plant species, and inclusion of an intron in these constructs had a consistently enhancing effect. Intron-containing constructs (ihpRNA) generally gave 90-100% of independent transgenic plants showing silencing. The degree of silencing with these constructs was much greater than that obtained using either co-suppression or anti-sense constructs. We have made a generic vector, pHANNIBAL, that allows a simple, single PCR product from a gene of interest to be easily converted into a highly effective ihpRNA silencing construct. We have also created a high-throughput vector, pHELLSGATE, that should facilitate the cloning of gene libraries or large numbers of defined genes, such as those in EST collections, using an in vitro recombinase system. This system may facilitate the large-scale determination and discovery of plant gene functions in the same way as RNAi is being used to examine gene function in Caenorhabditis elegans.


Asunto(s)
Silenciador del Gen , Vectores Genéticos , Técnicas de Sonda Molecular , Plantas Modificadas Genéticamente/genética , ARN sin Sentido , Arabidopsis/genética , Intrones , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Oryza , Sondas ARN , Empalme del ARN , Proyectos de Investigación , Nicotiana/genética , Transformación Genética
17.
Neuropsychologia ; 38(5): 666-76, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10689043

RESUMEN

A meta-analysis was conducted on studies of implicit memory for novel and familiar information in organic amnesic patients and healthy controls. Across studies, the amnesics performed equivalently to the controls on indirect memory tests for familiar information. However, the controls performed better than amnesics for indirect memory tests for novel item and novel associative information. This is in accord with memory theories which suggest that medial temporal lobe structures are essential for encoding and storing arbitrary associations between items or events.


Asunto(s)
Amnesia/psicología , Memoria , Pruebas Neuropsicológicas , Toma de Decisiones , Lóbulo Frontal/patología , Humanos , Aprendizaje
18.
Q J Exp Psychol A ; 52(2): 395-422, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10428685

RESUMEN

Four experiments were conducted to explore the possible involvement of explicit memory in an indirect memory test in which white noise accompanying old sentences was judged to be quieter than white noise accompanying new sentences (Jacoby, Allan, Collins & Larwill, 1988). Experiment 1 established that this effect lasted up to 1 week. Experiment 2 found that a group of amnesic patients showed a noise effect that was marginally above chance and not significantly less that that of their matched controls after a delay of one day. Effect of time pressure at test (Experiment 3) and divided attention at study (Experiment 4) suggested that the memory processes mediating the noise effect were not automatic, although the possibility that the processes involve enhanced fluency is also discussed.


Asunto(s)
Amnesia/fisiopatología , Atención/fisiología , Memoria/fisiología , Volición/fisiología , Adulto , Análisis de Varianza , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Factores de Tiempo
19.
Nucleic Acids Res ; 27(7): 1709-18, 1999 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-10076003

RESUMEN

We have used particle bombardment (biolistics) to deliver replication-competent wheat dwarf virus (WDV)-based constructs, carrying reporter gene sequences fused to the virion sense promoter (Pv) or the CaMV 35S promoter, to suspension culture cells and immature zygotic embryos of wheat. While the replication of WDV double-stranded DNA forms (replicons) was equivalent between wheat suspension culture cells and embryos, GUS reporter gene activity was 20-40 times higher in the embryo cultures. Maximum expression of WDV replicons occurred in the embryonic axis tissue of wheat embryos but their expression in suspension cells was compromised, compared with transiently maintained input plasmid DNA containing the same sequences. From these studies, we propose that WDV replicons are subject to a host cell-controlled competency for virion sense transcription. The term competency is used to distinguish between the phenomenon described here and control of gene expression by specific transcription factors. Control of competency is independent of Pv, the replacement 35S promoter and of the complementary sense control of virion sense expression involving specific sequences in Pv. We propose that factors controlling the competency for replicon expression may be present in cells which, as well as maintaining high rates of DNA synthesis, are totipotent. Cell type control of active chromatin, methylation of specific sequences in WDV minichromosomes and/or interaction of virus-encoded proteins with specific host factors are considered as possible mechanisms.


Asunto(s)
Geminiviridae/genética , Regulación de la Expresión Génica de las Plantas , Regulación Viral de la Expresión Génica , Triticum/virología , Caulimovirus/genética , Células Cultivadas , Replicación del ADN , ADN de Plantas , Plásmidos , Regiones Promotoras Genéticas , Replicón , Semillas
20.
Br J Psychiatry ; 174: 449-54, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10616615

RESUMEN

BACKGROUND: In healthy controls, preactivation of muscles by exercise results in enhanced motor-evoked potential (MEP) responses to transcranial magnetic stimulation (TMS). AIMS: We tested the hypothesis that medicated, depressed patients would show reduced post-exercise MEP facilitation compared with controls. METHOD: Ten patients with DSM-IV depression (two male, eight female) and ten controls (three male, seven female) participated. MEPs were elicited at rest, then after exercising the contralateral abductor pollicis brevis muscle, using TMS of the primary motor cortex. RESULTS: The mean MEP amplitude recorded after exercise (expressed as a percentage of baseline) was 210% in controls and 130% in patients. There was a significant difference in post-exercise MEP between patients and controls (P = 0.03). CONCLUSIONS: Post-exercise MEP facilitation was demonstrated in controls but not in patients. This supports the hypothesis that the modulation of cortical excitability may be impaired in depression.


Asunto(s)
Corteza Cerebral/fisiología , Trastorno Depresivo/fisiopatología , Potenciales Evocados Motores/fisiología , Ejercicio Físico/fisiología , Agitación Psicomotora/fisiopatología , Adulto , Estimulación Eléctrica/métodos , Femenino , Humanos , Masculino , Estimulación Magnética Transcraneal
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA