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1.
Klin Padiatr ; 229(1): 40-45, 2017 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-28147385

RESUMEN

Introduction Most pediatric patients require deep sedation for a TEE examination. We analyzed the data of our sedation protocols relating to all outpatient TEEs in patients under 18 years of age for the year 2011. On the basis of the data records of a total of 40 patients, we will describe our standard and compare it with the findings of the international literature. Material and Methods In a retrospective analysis, we inspected our sedation protocols in terms of patient-related data, vital parameters, drug applications, occurring complications and necessary interventions as well as nausea and vomiting during the post-sedative monitoring phase. Results In line with our standard, we applied atropine, midazolam, S-ketamine and propofol; complications occurred in 5 patients. They could be handled using simple measures. With regard to the vital parameters, no severe complications occurred. Dizziness was observed in 4 patients during the recovery phase; one patient complained about nausea and vomiting during the first fluid intake. All patients could be discharged 4 h after the termination of sedation. Conclusion Our standard is a practicable and safe procedure for preforming TEE examinations in pediatric outpatients.


Asunto(s)
Atención Ambulatoria , Sedación Consciente/métodos , Ecocardiografía Transesofágica , Adolescente , Periodo de Recuperación de la Anestesia , Anestésicos/administración & dosificación , Anestésicos/efectos adversos , Niño , Preescolar , Protocolos Clínicos , Sedación Consciente/efectos adversos , Sedación Consciente/normas , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Lactante , Masculino , Seguridad del Paciente , Estudios Retrospectivos
2.
Arch Orthop Trauma Surg ; 137(1): 141-145, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27787635

RESUMEN

INTRODUCTION: Digital pyogenic flexor tenosynovitis requires fast, aggressive treatment. Although this infection occurs frequently, treatment consensus is lacking. MATERIALS AND METHODS: Between 2011 and 2015, 22 patients with acute pyogenic flexor tenosynovitis were treated with a single open debridement followed by irrigation; the incision was closed and a 10-day antibiotic course was administered. The average incision-to-suture time was 25 min, and the average hospital stay was 4 days. Recovery was uncomplicated for 20 patients, while two were reoperated, one due to germ resistance and the other due to necrotizing fasciitis. At an average of 30 month postoperatively, 21 of the 22 patients were available for follow-up. The affected finger was inspected, and sensibility, range of motion, and grip force were compared with the opposite side, and the DASH score was determined. Each patient documented pain in the affected finger at rest and during activity, and rated overall satisfaction with the treatment on a visual analogue scale. RESULTS: Almost all patients were free of pain at follow-up and very satisfied. Compared to the contralateral side, each of the affected fingers had the same range of motion and sensibility. Grip force was similar on both sides. The average DASH score was 35 points. CONCLUSION: A single open debridement with irrigation and primary wound closure followed by 10 days of antibiotic treatment resolved uncomplicated pyogenic flexor tenosynovitis. After 2 and a half years, the treatment yielded high patient satisfaction with neither functional nor subjective impairment of the affected finger.


Asunto(s)
Antibacterianos/uso terapéutico , Desbridamiento , Dedos/cirugía , Tenosinovitis/cirugía , Irrigación Terapéutica , Adolescente , Adulto , Anciano , Niño , Desbridamiento/efectos adversos , Fascitis Necrotizante/cirugía , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Complicaciones Posoperatorias , Rango del Movimiento Articular , Reoperación , Infección de la Herida Quirúrgica/cirugía , Tenosinovitis/tratamiento farmacológico , Adulto Joven
3.
Mol Psychiatry ; 20(11): 1386-96, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25450228

RESUMEN

In aetiologically complex illnesses such as schizophrenia, there is no direct link between genotype and phenotype. Intermediate phenotypes could help clarify the underlying biology and assist in the hunt for genetic vulnerability variants. We have previously shown that cognition shares substantial genetic variance with schizophrenia; however, it is unknown if this reflects pleiotropic effects, direct causality or some shared third factor that links both, for example, brain volume (BV) changes. We quantified the degree of net genetic overlap and tested the direction of causation between schizophrenia liability, brain structure and cognition in a pan-European schizophrenia twin cohort consisting of 1243 members from 626 pairs. Cognitive deficits lie upstream of the liability for schizophrenia with about a quarter of the variance in liability to schizophrenia explained by variation in cognitive function. BV changes lay downstream of schizophrenia liability, with 4% of BV variation explained directly by variation in liability. However, our power to determine the nature of the relationship between BV deviation and schizophrenia liability was more limited. Thus, while there was strong evidence that cognitive impairment is causal to schizophrenia liability, we are not in a position to make a similar statement about the relationship between liability and BV. This is the first study to demonstrate that schizophrenia liability is expressed partially through cognitive deficits. One prediction of the finding that BV changes lie downstream of the disease liability is that the risk loci that influence schizophrenia liability will thereafter influence BV and to a lesser extent. By way of contrast, cognitive function lies upstream of schizophrenia, thus the relevant loci will actually have a larger effect size on cognitive function than on schizophrenia. These are testable predictions.


Asunto(s)
Encéfalo/patología , Trastornos del Conocimiento/etiología , Modelos Genéticos , Esquizofrenia , Adulto , Estudios de Cohortes , Europa (Continente) , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Escalas de Valoración Psiquiátrica , Esquizofrenia/complicaciones , Esquizofrenia/genética , Esquizofrenia/patología , Estadística como Asunto , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética , Adulto Joven
4.
Nervenarzt ; 87(1): 82-7, 2016 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-26099499

RESUMEN

BACKGROUND: Patients with mental illnesses, especially with schizophrenia, suffer from stigma and discrimination. In addition, the stigma is a barrier to recognising and treating patients with first-episode psychosis; however, a self-rating instrument that assesses the general burden due to stigma experiences is still lacking. MATERIAL AND METHODS: A total of N = 48 patients with first-episode schizophrenia who were participants in the multicenter first-episode (long-term) study within the German Research Network on Schizophrenia, completed a newly developed self-rating questionnaire to assess the burden due to stigma experiences (B-STE). The following variables were analyzed as possible correlates: psychopathology (CGI, PANSS, CDSS and HAM-D), global functioning (GAF), social adjustment (SAS), self-esteem (FSKN), as well as quality of life (LQLP), subjective well-being under neuroleptic treatment (SWN) and anticipated stigma (PDDQ). RESULTS: Of the participants 25 % showed an increased burden due to stigma experiences, which correlated with a lower quality of life, lower subjective well-being under neuroleptic treatment, lower self-esteem and higher anticipated stigma. The results indicate that patients rated higher on the CGI scale who are at the same time better socially adjusted (SAS), are more intensely affected by the burden due to stigma experiences. CONCLUSION: The short self-rating instrument burden due to stigma experiences (B-STE) can help to identify patients who might benefit from therapeutic or educational interventions to support coping with stigma experiences.


Asunto(s)
Calidad de Vida/psicología , Esquizofrenia/epidemiología , Psicología del Esquizofrénico , Discriminación Social/psicología , Discriminación Social/estadística & datos numéricos , Estereotipo , Adulto , Distribución por Edad , Femenino , Alemania/epidemiología , Humanos , Masculino , Prevalencia , Esquizofrenia/diagnóstico , Distribución por Sexo
5.
Psychol Med ; 45(1): 143-52, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25065377

RESUMEN

BACKGROUND: Genetic variation in the gene encoding ZNF804A, a risk gene for schizophrenia, has been shown to affect brain functional endophenotypes of the disorder, while studies of white matter structure have been inconclusive. METHOD: We analysed effects of ZNF804A single nucleotide polymorphism rs1344706 on grey and white matter using voxel-based morphometry (VBM) in high-resolution T1-weighted magnetic resonance imaging scans of 62 schizophrenia patients and 54 matched healthy controls. RESULTS: We found a significant (p < 0.05, family-wise error corrected for multiple comparisons) interaction effect of diagnostic group x genotype for local grey matter in the left orbitofrontal and right and left lateral temporal cortices, where patients and controls showed diverging effects of genotype. Analysing the groups separately (at p < 0.001, uncorrected), variation in rs1344706 showed effects on brain structure within the schizophrenia patients in several areas including the left and right inferior temporal, right supramarginal/superior temporal, right and left inferior frontal, left frontopolar, right and left dorsolateral/ventrolateral prefrontal cortices, and the right thalamus, as well as effects within the healthy controls in left lateral temporal, right anterior insula and left orbitofrontal cortical areas. We did not find effects of genotype of regional white matter in either of the two cohorts. CONCLUSIONS: Our findings demonstrate effects of ZNF804A genetic variation on brain structure, with diverging regional effects in schizophrenia patients and healthy controls in frontal and temporal brain areas. These effects, however, might be dependent on the impact of other (genetic or non-genetic) disease factors.


Asunto(s)
Sustancia Gris/fisiopatología , Esquizofrenia/genética , Esquizofrenia/fisiopatología , Adulto , Análisis de Varianza , Femenino , Variación Genética , Genotipo , Voluntarios Sanos , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Polimorfismo Genético , Factores de Riesgo , Lóbulo Temporal/fisiopatología , Sustancia Blanca/fisiopatología
6.
Mol Psychiatry ; 19(3): 317-24, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23478748

RESUMEN

The identification of an ultra-high risk (UHR) profile for psychosis and a greater understanding of its prodrome have led to increasing interest in early intervention to delay or prevent the onset of psychotic illness. In a randomized placebo-controlled trial, we have identified long-chain ω-3 (ω-3) polyunsaturated fatty acid (PUFA) supplementation as potentially useful, as it reduced the rate of transition to psychosis by 22.6% 1 year after baseline in a cohort of 81 young people at UHR of transition to psychosis. However, the mechanisms whereby the ω-3 PUFAs might be neuroprotective are incompletely understood. Here, we report on the effects of ω-3 PUFA supplementation on intracellular phospholipase A2 (inPLA(2)) activity, the main enzymes regulating phospholipid metabolism, as well as on peripheral membrane lipid profiles in the individuals who participated in this randomized placebo-controlled trial. Patients were studied cross-sectionally (n=80) and longitudinally (n=65) before and after a 12-week intervention with 1.2 g per day ω-3 PUFAs or placebo, followed by a 40-week observation period to establish the rates of transition to psychosis. We investigated inPLA(2) and erythrocyte membrane FAs in the treatment groups (ω-3 PUFAs vs placebo) and the outcome groups (psychotic vs non-psychotic). The levels of membrane ω-3 and ω-6 PUFAs and inPLA(2) were significantly related. Some of the significant associations (that is, long-chain ω-6 PUFAs, arachidonic acid) with inPLA(2) activity were in opposite directions in individuals who did (a positive correlation) and who did not (a negative correlation) transition to psychosis. Supplementation with ω-3 PUFA resulted in a significant decrease in inPLA(2) activity. We conclude that ω-3 PUFA supplementation may act by normalizing inPLA(2) activity and δ-6-desaturase-mediated metabolism of ω-3 and ω-6 PUFAs, suggesting their role in neuroprogression of psychosis.


Asunto(s)
Ácidos Grasos Omega-3/farmacología , Fosfolipasas A2/efectos de los fármacos , Trastornos Psicóticos/metabolismo , Adolescente , Adulto , Estudios Transversales , Progresión de la Enfermedad , Método Doble Ciego , Membrana Eritrocítica/efectos de los fármacos , Membrana Eritrocítica/metabolismo , Ácidos Grasos Omega-3/uso terapéutico , Ácidos Grasos Omega-6/metabolismo , Femenino , Humanos , Líquido Intracelular/efectos de los fármacos , Líquido Intracelular/metabolismo , Estudios Longitudinales , Masculino , Fosfolipasas A2/sangre , Trastornos Psicóticos/dietoterapia , Factores de Riesgo , Adulto Joven
7.
Psychol Med ; 44(4): 811-20, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23795679

RESUMEN

BACKGROUND: Recent studies have provided strong evidence that variation in the gene neurocan (NCAN, rs1064395) is a common risk factor for bipolar disorder (BD) and schizophrenia. However, the possible relevance of NCAN variation to disease mechanisms in the human brain has not yet been explored. Thus, to identify a putative pathomechanism, we tested whether the risk allele has an influence on cortical thickness and folding in a well-characterized sample of patients with schizophrenia and healthy controls. METHOD: Sixty-three patients and 65 controls underwent T1-weighted magnetic resonance imaging (MRI) and were genotyped for the single nucleotide polymorphism (SNP) rs1064395. Folding and thickness were analysed on a node-by-node basis using a surface-based approach (FreeSurfer). RESULTS: In patients, NCAN risk status (defined by AA and AG carriers) was found to be associated with higher folding in the right lateral occipital region and at a trend level for the left dorsolateral prefrontal cortex. Controls did not show any association (p > 0.05). For cortical thickness, there was no significant effect in either patients or controls. CONCLUSIONS: This study is the first to describe an effect of the NCAN risk variant on brain structure. Our data show that the NCAN risk allele influences cortical folding in the occipital and prefrontal cortex, which may establish disease susceptibility during neurodevelopment. The findings suggest that NCAN is involved in visual processing and top-down cognitive functioning. Both major cognitive processes are known to be disturbed in schizophrenia. Moreover, our study reveals new evidence for a specific genetic influence on local cortical folding in schizophrenia.


Asunto(s)
Trastorno Bipolar/patología , Corteza Cerebral/patología , Proteoglicanos Tipo Condroitín Sulfato/genética , Lectinas Tipo C/genética , Imagen por Resonancia Magnética/métodos , Proteínas del Tejido Nervioso/genética , Esquizofrenia/patología , Adulto , Trastorno Bipolar/genética , Corteza Cerebral/metabolismo , Genotipo , Humanos , Imagen por Resonancia Magnética/instrumentación , Neurocano , Lóbulo Occipital/metabolismo , Lóbulo Occipital/patología , Polimorfismo de Nucleótido Simple/genética , Corteza Prefrontal/metabolismo , Corteza Prefrontal/patología , Riesgo , Esquizofrenia/genética
8.
Acta Psychiatr Scand ; 127(6): 474-81, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22957829

RESUMEN

OBJECTIVE: To evaluate the predictive validity of early response in first-episode schizophrenia within a 1-year follow-up trial and to compare the resulting cutoff to the currently proposed early response definition (20% improvement by week 2). METHOD: Receiver operator characteristic (ROC) analyses were used to identify the predictive validity of the psychopathological improvement of treatment from week 1 to week 8, regarding the maintenance of response until week 52 as well as to define the most reasonable cutoff in 132 first-episode patients. The Youden Index (maximum of sensitivity and specificity) was used to compare the newly developed and the commonly used early response definition. RESULTS: Starting with week 6, a reasonable validity to predict the maintenance of response was found (area under the curve = 0.721) with the best fitting cutoff being a 51.6% PANSS total score improvement. Using this cutoff 74 patients (56%) were correctly identified to become responder and maintain response during follow-up (sensitivity: 0.747). The Youden Index was higher applying the newly developed early response cutoff featuring higher specificity compared to the commonly used early response definition. CONCLUSION: Regarding long-term treatment, it seems more appropriate to base predictions of the patient's maintenance of response not before 6 weeks of treatment.


Asunto(s)
Antipsicóticos/uso terapéutico , Haloperidol/uso terapéutico , Risperidona/uso terapéutico , Esquizofrenia/tratamiento farmacológico , Adulto , Progresión de la Enfermedad , Método Doble Ciego , Femenino , Humanos , Estudios Longitudinales , Masculino , Curva ROC , Esquizofrenia/diagnóstico , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
9.
Nervenarzt ; 84(11): 1369-70, 1372-4, 1376-8 passim, 2013 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-24166017

RESUMEN

This article is based on an evaluation carried out by the DGPPN in 2011 surveying 50 German university and non-university institutions about the scientific research output focussing on psychiatric and psychotherapeutic research. The results of the survey show that on average there are 1 to 2 professors with 12 assistants scientifically active per institution. According to self-disclosure an estimated 1.8 million Euros of external funds are raised each year.Compared to international standards regarding the illnesses major depression, schizophrenia and alcohol abuse, Germany ranks second and third place behind the USA and the UK or Canada in terms of publication output. In terms of authors and institutions, German scientists and universities rank in the upper third to upper tenth for these illnesses. These data show that psychiatric research in Germany is not only internationally competitive but outstanding in its excellent achievements in these fields. Unfortunately, many funding programmes are limited to a 3-6 year period. In view of this fact and in order to achieve a long-term improvement in the translation of funding structures, as in the US (NIMH) or the UK (MRC) to benefit the mentally ill the implementation of a German centre for mental disorders is inevitable.


Asunto(s)
Investigación Biomédica/economía , Investigación Biomédica/estadística & datos numéricos , Psiquiatría/economía , Psiquiatría/estadística & datos numéricos , Psicoterapia/economía , Psicoterapia/estadística & datos numéricos , Recolección de Datos , Alemania , Internacionalidad
11.
Mol Psychiatry ; 15(5): 463-72, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-18936756

RESUMEN

Several studies have reported structural brain abnormalities, decreased myelination and oligodendrocyte dysfunction in schizophrenia. In the central nervous system, glia-derived de novo synthesized cholesterol is essential for both myelination and synaptogenesis. Previously, we demonstrated in glial cell lines that antipsychotic drugs induce the expression of genes involved in cholesterol and fatty acids biosynthesis through activation of the sterol regulatory element binding protein (SREBP) transcription factors, encoded by the sterol regulatory element binding transcription factor 1 (SREBF1) and sterol regulatory element binding transcription factor 2 (SREBF2) genes. Considering the importance of these factors in the lipid biosynthesis and their possible involvement in antipsychotic drug effects, we hypothesized that genetic variants of SREBF1 and/or SREBF2 could affect schizophrenia susceptibility. We therefore conducted a HapMap-based association study in a large German sample, and identified association between schizophrenia and five markers in SREBF1 and five markers in SREBF2. Follow-up studies in two independent samples of Danish and Norwegian origin (part of the Scandinavian collaboration of psychiatric etiology study, SCOPE) replicated the association for the five SREBF1 markers and for two markers in SREBF2. A combined analysis of all samples resulted in highly significant genotypic P-values of 9 x 10(-4) for SREBF1 (rs11868035, odd ration (OR)=1.26, 95% confidence interval (CI) (1.09-1.45)) and 4 x 10(-5) for SREBF2 (rs1057217, OR=1.39, 95% CI (1.19-1.63)). This finding strengthens the hypothesis that SREBP-controlled cholesterol biosynthesis is involved in the etiology of schizophrenia.


Asunto(s)
Antipsicóticos/uso terapéutico , Predisposición Genética a la Enfermedad , Lipogénesis/efectos de los fármacos , Polimorfismo de Nucleótido Simple/genética , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 2 de Unión a Elementos Reguladores de Esteroles/genética , Adulto , Estudios de Casos y Controles , Cromosomas Humanos Par 17/genética , Cromosomas Humanos Par 22/genética , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Alemania , Humanos , Lipogénesis/genética , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Países Escandinavos y Nórdicos
12.
Psychol Med ; 40(11): 1879-86, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20056020

RESUMEN

BACKGROUND: With regard to current neurobiological theories, the aim of our study was to examine possible alterations of temporal and frontal lobe volume in panic disorder (PD). METHOD: Seventeen in-patients with PD and a group of healthy control subjects (HC) matched for age and gender were investigated by quantitative volumetric magnetic resonance imaging (MRI). Structures of interest were: the temporal lobe, the amygdala-hippocampus complex (AHC) and the frontal lobe. In addition, a voxel-based morphometry (VBM) analysis implemented in Statistical Parametric Mapping 5 (SPM5) was used for a more detailed assessment of possible volume alterations. Modulated grey matter (GM) images were used to test our a priori hypotheses and to present the volumetric results. RESULTS: Quantitative volumetric MRI revealed a bilateral reduction in temporal lobe volume in patients with PD compared to HC subjects. The AHC was normal. The right frontal lobe volume was also decreased. Using VBM we detected a significant GM volume reduction in the right middle temporal gyrus [Brodmann area (BA) 21] in patients with PD. In addition, there was a reduction in GM volume in the medial part of the orbitofrontal cortex (BA 11). CONCLUSIONS: Our results of reduced temporal and frontal lobe volume in PD are in agreement with prior studies. By using a recent VBM approach we were able to assess the abnormalities more precisely. The location of GM volume reduction in the right middle temporal gyrus and medial orbitofrontal cortex lends further support to recent aetiological models of PD.


Asunto(s)
Lóbulo Frontal/patología , Trastorno de Pánico/patología , Lóbulo Temporal/patología , Adulto , Amígdala del Cerebelo/patología , Estudios de Casos y Controles , Femenino , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tamaño de los Órganos
13.
Psychol Med ; 39(11): 1809-19, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19379537

RESUMEN

BACKGROUND: There is increasing evidence that the frequently reported working memory impairments in schizophrenia might be partly due to an alteration in the functional connectivity between task-relevant areas. However, little is known about the functional connectivity patterns in schizophrenia patients during learning processes. In a previous study, Koch et al. [Neuroscience (2007) 146, 1474-1483] have demonstrated stronger exponential activation decreases in schizophrenia patients during overlearning of short-term memory material. The question arises whether these differential temporal patterns of activation in schizophrenia patients and controls are going along with changes in task-related functional connectivity. METHOD: Therefore, in the current study, 13 patients with schizophrenia and 13 controls were studied while performing a short-term memory task associated with increasing overlearning of verbal stimulus material. Functional connectivity was investigated by analyses of psychophysiological interactions (PPI). RESULTS: Results revealed significant task-related modulation of functional connectivity between the left dorsolateral prefrontal cortex (DLPFC) and a network including the right DLPFC, left ventrolateral prefrontal cortex, premotor cortex, right inferior parietal cortex, left and right cerebellum as well as the left occipital lobe in patients during the course of overlearning and practice. No significant PPI results were detectable in controls. CONCLUSIONS: Activation changes with practice were associated with high functional connectivity between task-relevant areas in schizophrenia patients. This could be interpreted as a compensatory resource allocation and network integration in the context of cortical inefficiency and may be a specific neurophysiological signature underlying the pathophysiology of schizophrenia.


Asunto(s)
Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/rehabilitación , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Imagen por Resonancia Magnética , Sobreaprendizaje/fisiología , Oxígeno/sangre , Práctica Psicológica , Corteza Prefrontal/fisiopatología , Esquizofrenia/fisiopatología , Esquizofrenia/rehabilitación , Psicología del Esquizofrénico , Adolescente , Adulto , Atención/fisiología , Mapeo Encefálico , Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Trastornos del Conocimiento/psicología , Dominancia Cerebral/fisiología , Femenino , Humanos , Potenciación a Largo Plazo/fisiología , Masculino , Memoria a Corto Plazo/fisiología , Red Nerviosa/fisiopatología , Pruebas Neuropsicológicas , Tiempo de Reacción/fisiología , Aprendizaje Verbal/fisiología , Adulto Joven
14.
Synapse ; 63(5): 429-42, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19184997

RESUMEN

There is evidence that the dopaminergic system is involved in probabilistic reinforcement learning and reward-related decision-making. However, little is known about the effects of external dopaminergic challenges on processing of uncertainty in decision-making tasks. Therefore, the present study examined changes in fMRI activation patterns in a natural sampling paradigm. Decision making under uncertainty was examined before and after administration of a single dose of 40 mg methylphenidate as an acute dopaminergic pharmacological challenge. We found that the level of uncertainty was positively correlated with activations in the prefrontal cortex. Conversely, negative correlations with uncertainty were found in the left hippocampus, right amygdale, and right middle temporal gyrus. The drug intervention with methylphenidate revealed a differential picture. Uncertain information processing was associated with higher activation in the parietal association cortex and posterior cingulate cortex after placebo relative to methylphenidate. The methylphenidate challenge relative to placebo was associated with higher left and right parahippocampal as well as cerebellar activation under uncertainty. Apparently, the pro-dopaminergic pharmacological influence induces a relative shift towards recruitment of hippocampal areas under uncertainty, whereas under placebo conditions, higher levels of parietal cortex activations are involved in the task. The findings suggest a role of dopamine in uncertainty processing and shed light on the pharmacological mechanisms of methylphenidate.


Asunto(s)
Encéfalo , Técnicas de Apoyo para la Decisión , Inhibidores de Captación de Dopamina/farmacología , Dopamina/metabolismo , Imagen por Resonancia Magnética/métodos , Metilfenidato/farmacología , Adulto , Análisis de Varianza , Encéfalo/irrigación sanguínea , Encéfalo/efectos de los fármacos , Encéfalo/fisiología , Mapeo Encefálico , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Metilfenidato/sangre , Pruebas Neuropsicológicas , Oxígeno/sangre , Estimulación Luminosa , Desempeño Psicomotor/efectos de los fármacos , Tiempo de Reacción , Incertidumbre , Adulto Joven
15.
J Cell Biol ; 106(5): 1445-52, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3286658

RESUMEN

The orderly progression of eukaryotic cells from interphase to mitosis requires the close coordination of various nuclear and cytoplasmic events. Studies from our laboratory and others on animal cells indicate that two activities, one present mainly in mitotic cells and the other exclusively in G1-phase cells, play a pivotal role in the regulation of initiation and completion of mitosis, respectively. The purpose of this study was to investigate whether these activities are expressed in the slime mold Physarum polycephalum in which all the nuclei traverse the cell cycle in natural synchrony. Extracts were prepared from plasmodia in various phases of the cell cycle and tested for their ability to induce germinal vesicle breakdown and chromosome condensation after microinjection into Xenopus laevis oocytes. We found that extract of cells at 10-20 min before metaphase consistently induced germinal vesicle breakdown in oocytes. Preliminary characterization, including purification on a DNA-cellulose affinity column, indicated that the mitotic factors from Physarum were functionally very similar to HeLa mitotic factors. We also identified a number of mitosis-specific antigens in extracts from Physarum plasmodia, similar to those of HeLa cells, using the mitosis-specific monoclonal antibodies MPM-2 and MPM-7. Interestingly, we also observed an activity in Physarum at 45 min after metaphase (i.e., in early S phase since it has no G1) that is usually present in HeLa cells only during the G1 phase of the cell cycle. These are the first studies to show that maturation-promoting factor activity is present in Physarum during mitosis and is replaced by the G1 factor (or anti-maturation-promoting factor) activity in a postmitotic stage. A comparative study of these factors in this slime mold and in mammalian cells would be extremely valuable in further understanding their function in the regulation of eukaryotic cell cycle and their evolutionary relationship to one another.


Asunto(s)
Sustancias de Crecimiento/análisis , Mitosis , Oocitos/crecimiento & desarrollo , Physarum/fisiología , Animales , Anticuerpos Monoclonales , Antígenos Fúngicos/análisis , Ciclo Celular , Electroforesis en Gel de Poliacrilamida , Inhibidores de Crecimiento/farmacología , Sustancias de Crecimiento/fisiología , Células HeLa , Humanos , Inmunoensayo , Interfase , Factor Promotor de Maduración , Metafase , Microinyecciones , Physarum/citología , Xenopus laevis
16.
Nervenarzt ; 80(1): 62-3, 65-7, 2009 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-18781290

RESUMEN

We report a patient with early-onset autosomal dominant dementia. The CSF showed increased levels of tau protein and decreased amyloid beta (ratio 42:40) typical for Alzheimer's disease. Cerebral MRI revealed vascular lesions and white-matter changes around the posterior horns of the ventricles with only moderate atrophy of the brain. Susceptibility-weighted imaging detected multiple small hemorrhagic changes. Gene analysis revealed amyloid precursor protein (APP) locus duplication as the cause of hereditary Alzheimer's dementia. The co-occurrence of CSF changes typical for Alzheimer's disease and MRI findings of cerebral amyloid angiopathy is remarkable, as it is also described for APP locus duplication. In conjunction with a family history suggestive of hereditary dementia, such a constellation should lead to enhanced gene analysis.


Asunto(s)
Enfermedad de Alzheimer/congénito , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/genética , Heterocigoto , Fragmentos de Péptidos/genética , Humanos , Masculino , Persona de Mediana Edad , Linaje
17.
Neuroimage ; 43(3): 645-55, 2008 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18761094

RESUMEN

Functional imaging studies are indicating disrupted error monitoring and executive control in a fronto-cingulate network in major depression. However, univariate statistical analyses allow only for a limited assessment of directed neuronal interactions. Therefore, the present study used dynamic causal modeling (DCM) of a fronto-cingulate network to re-analyze the data from a preceding fMRI study in 16 drug-free patients with major depression and 16 healthy controls using the Stroop Color-Word Test (Wagner et al., 2006). In both groups, a significant reciprocal interregional connectivity was found in a cognitive control network including prefrontal cortex (PFC) and dorsal anterior cingulate cortex (ACC). With regard to intrinsic connections we detected a significant difference for dorsal to rostral ACC connectivity between depressive patients and controls in terms of higher connectivity in patients. Additionally, a task by group interaction was observed for the bilinear interaction signaling enhanced task-related input from the dorsal to rostral ACC in subjects with depression. This could be related to the inability of patients to down-regulate rostral ACC activation as observed in the previous univariate analysis. The correlation between interference scores and intrinsic connections from dorsal ACC to dorsolateral PFC (DLPFC) was significant for both groups together, but no significant group differences in correlations could be detected. Thus, the observed relationship between control functions of the dorsal ACC exerted over DLPFC and interference scores appears to be valid in both patients with depression and controls. The findings are consistent with current models of a differential involvement of the fronto-cingulate system in the pathophysiology of major depression.


Asunto(s)
Mapeo Encefálico , Encéfalo/fisiopatología , Trastorno Depresivo Mayor/fisiopatología , Modelos Neurológicos , Vías Nerviosas/fisiopatología , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética
18.
Neuroscience ; 153(1): 54-62, 2008 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-18359576

RESUMEN

Working memory (WM) deficits are core symptoms of schizophrenia. Differing behavioral performance is known to represent a potent moderating variable when investigating the neural correlates of working memory in patients with schizophrenia compared with healthy controls. The present functional magnetic resonance imaging study examined performance-matched cerebral activity during correct WM retrieval by balancing the mean number of correct responses as well as the mean response times between patients and controls and analyzing remaining correct trials. Forty-one schizophrenia patients and 41 healthy controls performed an event-related Sternberg task allowing for analysis of correctly remembered trials. Correct retrieval was associated with activation in a bilateral fronto-parieto-occipital network comprising mainly the dorsolateral prefrontal cortex, ventrolateral prefrontal cortex and superior parietal cortex in controls and, to a weaker degree, in patients. Direct group comparison revealed significantly decreased activations in patients in the posterior (Brodmann area (BA) 31) and anterior (BA 32) cingulate cortex (ACC) and the medial caudate bilaterally when matching for performance. When matching for performance and response speed there was additional hypoactivation in the insula. Mean response times were negatively correlated with cingulate and caudate activation only in controls. Present findings suggest that during efficient WM retrieval processing patients exhibit only slightly impaired activation in a task-specific network containing mainly prefrontal and superior parietal areas. However, hypoactivation of areas predominantly responsible for cognitive control and response execution seems to remain even under performance-matched conditions. Given the relevant role of the caudate and the ACC in dopaminergically mediated executive processing, the results bear crucial implications for the psychopathology of schizophrenia.


Asunto(s)
Cuerpo Estriado/fisiopatología , Memoria a Corto Plazo , Red Nerviosa/fisiopatología , Corteza Prefrontal/fisiopatología , Esquizofrenia/fisiopatología , Adulto , Mapeo Encefálico , Cognición/fisiología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/fisiopatología , Cuerpo Estriado/anatomía & histología , Femenino , Lateralidad Funcional/fisiología , Giro del Cíngulo/anatomía & histología , Giro del Cíngulo/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Memoria a Corto Plazo/fisiología , Recuerdo Mental , Red Nerviosa/anatomía & histología , Vías Nerviosas/anatomía & histología , Vías Nerviosas/fisiopatología , Pruebas Neuropsicológicas , Lóbulo Occipital/anatomía & histología , Lóbulo Parietal/anatomía & histología , Lóbulo Parietal/fisiopatología , Corteza Prefrontal/anatomía & histología , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico
19.
J Phys Condens Matter ; 20(20): 204115, 2008 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-21694244

RESUMEN

Mn(x)Zn(1-x)Fe(2)O(4)-based magnetic fluids with x = 0.1-0.9 are synthesized by coprecipitation. The samples are heated in a radio frequency (rf) magnetic field using an rf generator at different powers, and the temperature is measured as function of time using an optical thermometer. The heating effect of the dispersed magnetic nanoparticles is proportional to the imaginary part of the dynamic magnetic susceptibility of the ferrofluid, a quantity that depends on the temperature through the magnetization of the ferrite nanoparticles and the Néel or Brownian relaxation times, respectively. We propose an extrapolation method to actuate the Curie temperatures of the dispersed magnetic nanoparticles. By means of appropriate fitting functions for (dT/dt) versus T for both the heating and the cooling process, we deduce the Curie temperature of the samples under investigation. For Mn(x)Zn(1-x)Fe(2)O(4)-based magnetic nanoparticles the Curie temperatures decrease with increasing Zn content. They turn out to be lower than the literature values for bulk Mn(x)Zn(1-x)Fe(2)O(4), a phenomenon which is generally observed for phase transitions of nanocrystalline materials.

20.
Ann Oncol ; 18(11): 1875-81, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17804477

RESUMEN

BACKGROUND: Depressive symptoms are a major complaint reported by cancer patients. Somatic and affective symptoms can contribute to depression. PATIENTS AND METHODS: We investigated the prevalence of somatic and affective depressive symptoms with the Beck Depression Inventory (BDI) in 213 hospitalized cancer patients prior to the start of chemotherapy. RESULTS: Seventeen of 213 patients (8%) were screened positive for major depression; 40 (19%) had mild to moderate depressive symptoms. The corresponding figures for somatic and affective symptoms were 33.3% and 2.8% in the patients with major depression and 23.0% and 8.0% in those with mild to moderate depressive symptoms. Female patients, patients with solid tumour and those with functional limitations had significantly higher mean scores. All differences were related to higher scores in somatic and not in affective items. CONCLUSIONS: Most alterations in the BDI in cancer patients are related to somatic and not to affective symptoms and may be attributed not to depression but to severity of the underlying disease.


Asunto(s)
Trastorno Depresivo/diagnóstico , Trastorno Depresivo/epidemiología , Neoplasias/epidemiología , Calidad de Vida , Adaptación Psicológica , Adolescente , Adulto , Distribución por Edad , Anciano , Estudios de Casos y Controles , Causalidad , Comorbilidad , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Hospitales Universitarios , Humanos , Entrevista Psicológica/métodos , Masculino , Persona de Mediana Edad , Neoplasias/diagnóstico , Neoplasias/psicología , Prevalencia , Probabilidad , Escalas de Valoración Psiquiátrica , Medición de Riesgo , Distribución por Sexo , Perfil de Impacto de Enfermedad , Estadísticas no Paramétricas , Estrés Psicológico , Encuestas y Cuestionarios
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