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1.
Eat Weight Disord ; 24(6): 1155-1164, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29397562

RESUMEN

BACKGROUND: Intimacy is a key psychological problem in anorexia nervosa (AN). Empirical evidence, including neurobiological underpinnings, is however, scarce. OBJECTIVE: In this study, we evaluated various emotional stimuli including intimate stimuli experienced in patients with AN and non-patients, as well as their cerebral response. METHODS: Functional magnetic resonance imaging was conducted using stimuli with positive, neutral, negative and intimate content. Participants (14 AN patients and 14 non-patients) alternated between passive viewing and explicit emotion regulation. RESULTS: Intimate stimuli were experienced less positively in AN patients compared to non-patients. AN patients showed decreased cerebral responses in superior parietal cortices in response to positive and intimate stimuli. Intimate stimuli led to stronger activation of the orbitofrontal cortex, and lower activation of the bilateral precuneus in AN patients. Orbitofrontal responses decreased in AN patients during explicit emotion regulation. CONCLUSIONS: These results show that intimate stimuli are of particular importance in AN patients, who show experiential differences compared to non-patients and altered activation of orbitofrontal and parietal brain structures. This supports that AN patients have difficulties with intimacy, attachment, self-referential processing and body perception. LEVEL OF EVIDENCE: Level III, case-control study.


Asunto(s)
Anorexia Nerviosa/diagnóstico por imagen , Regulación Emocional , Lóbulo Frontal/diagnóstico por imagen , Relaciones Interpersonales , Lóbulo Parietal/diagnóstico por imagen , Anorexia Nerviosa/fisiopatología , Anorexia Nerviosa/psicología , Estudios de Casos y Controles , Emociones , Femenino , Lóbulo Frontal/fisiopatología , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética , Lóbulo Parietal/fisiopatología , Adulto Joven
2.
Psychol Med ; 44(1): 85-98, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23510549

RESUMEN

BACKGROUND: Emotional dysregulation is becoming increasingly recognized as an important feature of attention deficit hyperactivity disorder (ADHD). In this study, two experiments were conducted investigating the neural response to either verbally instructed fear (IF) or uninstructed (classically conditioned) fear (UF) using the skin conductance response (SCR) and functional magnetic resonance imaging (fMRI). METHOD: In the conditioning phase of the UF experiment (17 ADHD and 17 healthy controls), subjects experienced an unconditioned stimulus (UCS, unpleasant electrodermal stimulation) paired with a former neutral conditioned stimulus (CS+), whereas a control stimulus (CS-) was never paired with the UCS. In the subsequent test phase, only the CS+ and the CS- were presented. In the IF experiment (13 ADHD and 17 healthy controls), subjects were only told that an independently experienced UCS might occur together with the CS+ but not the CS- during testing. No UCS was presented. RESULTS: Groups did not detectably differ in SCR or neural responses to UF. In IF, ADHD patients showed a trend-line decreased SCR and significantly decreased activation of the dorsal anterior cingulate cortex (dACC), a region prominently involved in fear responding, to the CS+. This was accompanied by higher amygdala activation to the CS-. CONCLUSIONS: During IF, ADHD patients showed deficits in regions centrally involved in fear learning and expression in terms of diminished CS+-related dACC and increased CS--related amygdala signals. This suggests an impaired processing of verbally transmitted aversive information, which is central for conveying fear information in social contexts. This result extends the growing literature on emotional alterations in ADHD.


Asunto(s)
Amígdala del Cerebelo/fisiopatología , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Condicionamiento Clásico/fisiología , Miedo/fisiología , Giro del Cíngulo/fisiopatología , Adulto , Encéfalo/fisiopatología , Estudios de Casos y Controles , Señales (Psicología) , Femenino , Neuroimagen Funcional , Respuesta Galvánica de la Piel , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto Joven
3.
Mol Cell Biol ; 8(8): 3114-21, 1988 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2463472

RESUMEN

We have previously shown that assembly of nucleosomes on the DNA template blocks transcription initiation by RNA polymerase II in vitro. In the studies reported here, we demonstrate that assembly of a complete RNA polymerase II preinitiation complex before nucleosome assembly results in nucleosomal templates which support initiation in vitro as efficiently as naked DNA. Control experiments prove that our observations are not the result of slow displacement of nucleosomes by the transcription machinery during chromatin assembly, nor are they an artifact of inefficient nucleosome deposition on templates already bearing an RNA polymerase. Thus, the RNA polymerase II preinitiation complex appears to be resistant to disruption by subsequent nucleosome assembly.


Asunto(s)
Nucleosomas/metabolismo , ARN Polimerasa II/metabolismo , Transcripción Genética , Cromatina/metabolismo , Células HeLa/metabolismo , Humanos , Plásmidos , ARN/biosíntesis , ARN/genética , ARN/aislamiento & purificación , Moldes Genéticos
4.
Gene Expr ; 5(3): 193-203, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8882642

RESUMEN

We previously demonstrated that RNA polymerase II promoters may be limited in strength not only at the step of transcription complex assembly, but also at initiation or promoter clearance. Here we report on experiments designed to test the possibility that steps following transcription complex assembly might be stimulated by transcriptional activators. Using an in vitro system in which we can independently measure the efficiency of assembly, initiation, and promoter clearance, we have investigated the mechanism by which the model activator GAL4-VP16 increases transcription from two promoters: a weak variant of Ad 2 ML with an altered TATA box, which is inefficient in transcription initiation, and the mouse beta-globin promoter, which is inefficient in promoter clearance. We found that whereas GAL4-VP16 is effective in stimulating both promoters, this increase resulted only from greater transcription complex assembly; the initiation and clearance steps were not affected. Because recent studies have suggested that the core transcription factors TFIIE and TFIIH might be important in promoter clearance, we also attempted to increase the initiation and clearance efficiencies of the Ad ML-TATA mutant and globin promoters by direct addition of excess TFIIE and TFIIH to partially purified preinitiation complexes assembled at each of these promoters. These factors had no effect on transcription by either of the preinitiation complexes.


Asunto(s)
Proteínas Fúngicas/metabolismo , Globinas/genética , ARN Polimerasa II/genética , Transactivadores/metabolismo , Transcripción Genética , Animales , Ratones , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/metabolismo
5.
Nervenarzt ; 76(3): 339-43, 2005 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-15696308

RESUMEN

Dialectical behavior therapy (DBT) was originally developed for suicidal female patients with borderline personality disorder (BPD). Meanwhile, DBT-based approaches to psychotherapy have also been successfully applied in other clinical groups. Previous studies of DBT in patients suffering from BPD and comorbid drug addiction are discussed, and an approach to DBT that has been devised by the authors for use in the treatment of alcoholics with comorbid BPD is described. As these patients have more severe clinical problems and less satisfactory treatment responses than do alcoholics without comorbid BPD, we must hope that this new approach will improve clinical outcomes in these severely ill patients.


Asunto(s)
Alcoholismo/complicaciones , Alcoholismo/terapia , Terapia Conductista/métodos , Trastorno de Personalidad Limítrofe/complicaciones , Trastorno de Personalidad Limítrofe/terapia , Humanos , Guías de Práctica Clínica como Asunto , Resultado del Tratamiento
6.
J Biol Chem ; 262(31): 14990-7, 1987 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-3667620

RESUMEN

We have investigated the formation of the first phosphodiester bond by RNA polymerase II in vitro. The template was a cloned DNA bearing the adenovirus 2 major late promoter; transcription factors and RNA polymerase II were provided by a HeLa cell nuclear extract. Dinucleotide primers and single nucleoside triphosphates were used as substrates. We found that accurate initiation does occur when only one phosphodiester bond can be formed; however, all of the resulting dinucleotide-primed trimers are abortively initiated. Synthesis of the trimers by RNA polymerase II requires ATP or dATP and is sensitive to low concentrations of alpha-amanitin. Treatments which abolish the ability of the preinitiation complex to synthesize long RNAs also eliminate the ability to abortively initiate. Abortive initiation proceeds for at least one-half h at 25 degrees C, at which point up to 4 mol of transcript/mol of template have been synthesized. The level of abortive initiation (per template molecule) is not significantly reduced by 0.025% Sarkosyl or by 10-fold dilution of the reaction, consistent with the initiation complex remaining intact during abortive initiation.


Asunto(s)
Adenovirus Humanos/genética , Genes Virales , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismo , Adenovirus Humanos/efectos de los fármacos , Adenovirus Humanos/enzimología , Amanitinas/farmacología , Secuencia de Bases , ADN/metabolismo , Células HeLa/metabolismo , Humanos , Cinética , Moldes Genéticos , Factores de Transcripción/metabolismo
7.
J Biol Chem ; 269(5): 3655-63, 1994 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-8106410

RESUMEN

We have measured the ability of three TATA box promoters, adenovirus 2 major late (Ad 2 ML), Ad 2 ML with a point mutation in the TATA box, and mouse beta-globin, to support abortive and productive RNA synthesis in vitro. We have also measured the ability of these promoters to direct the assembly of preinitiation complexes using a nuclease protection assay. The relative strengths in productive transcription, determined from the synthesis of RNAs 10 nucleotides or longer, were 12:6:1 for Ad 2 ML, mouse beta-globin, and the TATA mutant of Ad 2 ML. However, the TATA mutant was reduced only 4-fold in its ability to assemble preinitiation complexes, compared to Ad 2 ML. Complexes formed on the Ad 2 ML TATA mutant may therefore also be reduced in their ability to initiate transcription. The mouse beta-globin promoter directed assembly and initiation as well as Ad 2 ML, but the beta-globin transcription complexes were less able to clear the promoter, resulting in an increase in aborted transcripts at the expense of productive RNA synthesis. We have thus shown that the transcriptional strength of eukaryotic promoters may be determined not only at the step of transcription complex assembly but also at the level of promoter clearance and possibly at transcription initiation as well.


Asunto(s)
Adenovirus Humanos/genética , Regiones Promotoras Genéticas , ARN Polimerasa II/genética , TATA Box , Transcripción Genética , Adenovirus Humanos/enzimología , Animales , Secuencia de Bases , Núcleo Celular/metabolismo , Expresión Génica , Globinas/genética , Células HeLa , Humanos , Cinética , Ratones , Datos de Secuencia Molecular , Plásmidos , Mutación Puntual , ARN Polimerasa II/metabolismo , Moldes Genéticos
8.
J Biol Chem ; 266(33): 22537-44, 1991 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-1939271

RESUMEN

We have shown that accurate initiation of productive RNA synthesis in vitro at the adenovirus 2 major late promoter is accompanied by abortive initiation of very short transcripts (Luse, D. S., and Jacob, G. A. (1987) J. Biol. Chem. 262, 14990-14997). We made a set of sequence variants of this promoter, using every possible base at position -28 (in the TATA box) in the context of either the normal base (A) or a T at position +1 on the nontemplate strand. All changes from wild type reduced promoter strength. The two weakest promoters were 10- and 30-fold less active than wild type in productive RNA synthesis. We tested the possibility that the down mutations also caused an increase in the proportion of in vitro initiations which are abortive. This effect was seen only with the two weakest members of the promoter set. For these promoters, which share an A----C change at the -28 position of the TATA box, the ratio of abortive to productive initiations was 3-4-fold higher than for the other promoters. Interestingly, the sequence change at +1, although a down mutation, did not lead to an increase in abortive initiation.


Asunto(s)
Adenovirus Humanos/genética , ADN Viral/genética , Regiones Promotoras Genéticas , Transcripción Genética , Secuencia de Bases , Núcleo Celular/fisiología , Clonación Molecular , Células HeLa , Humanos , Sustancias Macromoleculares , Datos de Secuencia Molecular , ARN Viral/genética , Mapeo Restrictivo , TATA Box , Moldes Genéticos
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