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1.
Hum Brain Mapp ; 43(6): 1787-1803, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-35076988

RESUMEN

The amplitude of activation in brain resting state networks (RSNs), measured with resting-state functional magnetic resonance imaging, is heritable and genetically correlated across RSNs, indicating pleiotropy. Recent univariate genome-wide association studies (GWASs) explored the genetic underpinnings of individual variation in RSN activity. Yet univariate genomic analyses do not describe the pleiotropic nature of RSNs. In this study, we used a novel multivariate method called genomic structural equation modeling to model latent factors that capture the shared genomic influence on RSNs and to identify single nucleotide polymorphisms (SNPs) and genes driving this pleiotropy. Using summary statistics from GWAS of 21 RSNs reported in UK Biobank (N = 31,688), the genomic latent factor analysis was first conducted in a discovery sample (N = 21,081), and then tested in an independent sample from the same cohort (N = 10,607). In the discovery sample, we show that the genetic organization of RSNs can be best explained by two distinct but correlated genetic factors that divide multimodal association networks and sensory networks. Eleven of the 17 factor loadings were replicated in the independent sample. With the multivariate GWAS, we found and replicated nine independent SNPs associated with the joint architecture of RSNs. Further, by combining the discovery and replication samples, we discovered additional SNP and gene associations with the two factors of RSN amplitude. We conclude that modeling the genetic effects on brain function in a multivariate way is a powerful approach to learn more about the biological mechanisms involved in brain function.


Asunto(s)
Mapeo Encefálico , Red Nerviosa , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico/métodos , Estudio de Asociación del Genoma Completo , Humanos , Imagen por Resonancia Magnética/métodos , Red Nerviosa/fisiología
2.
Mol Psychiatry ; 26(6): 2277-2285, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32051549

RESUMEN

The gene encoding adhesion G protein-coupled receptor L3 (ADGRL3, also referred to as latrophilin 3 or LPHN3) has been associated with ADHD susceptibility in independent ADHD samples. We conducted a systematic review and a comprehensive meta-analysis to summarize the associations between the most studied ADGRL3 polymorphisms (rs6551665, rs1947274, rs1947275, and rs2345039) and both childhood and adulthood ADHD. Eight association studies (seven published and one unpublished) fulfilled criteria for inclusion in our meta-analysis. We also incorporated GWAS data for ADGRL3. In order to avoid overlapping samples, we started with summary statistics from GWAS samples and then added data from gene association studies. The results of our meta-analysis suggest an effect of ADGRL3 variants on ADHD susceptibility in children (n = 8724/14,644 cases/controls and 1893 families): rs6551665 A allele (Z score = -2.701; p = 0.0069); rs1947274 A allele (Z score = -2.033; p = 0.0421); rs1947275 T allele (Z score = 2.339; p = 0.0978); and rs2345039 C allele (Z score = 3.806; p = 0.0026). Heterogeneity was found in analyses for three SNPs (rs6551665, rs1947274, and rs2345039). In adults, results were not significant (n = 6532 cases/15,874 controls): rs6551665 A allele (Z score = 2.005; p = 0.0450); rs1947274 A allele (Z score = 2.179; p = 0.0293); rs1947275 T allele (Z score = -0.822; p = 0.4109); and rs2345039 C allele (Z score = -1.544; p = 0.1226). Heterogeneity was found just for rs6551665. In addition, funnel plots did not suggest publication biases. Consistent with ADGRL3's role in early neurodevelopment, our findings suggest that the gene is predominantly associated with childhood ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Adulto , Trastorno por Déficit de Atención con Hiperactividad/genética , Niño , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad/genética , Humanos , Polimorfismo de Nucleótido Simple/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Péptidos/genética
3.
Neuroimage ; 208: 116409, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31785419

RESUMEN

Investigating the contribution of biology to human cognition has assumed a bottom-up causal cascade where genes influence brain systems that activate, communicate, and ultimately drive behavior. Yet few studies have directly tested whether cognitive traits with overlapping genetic underpinnings also rely on overlapping brain systems. Here, we report a step-wise exploratory analysis of genetic and functional imaging overlaps among cognitive traits. We used twin-based genetic analyses in the human connectome project (HCP) dataset (N â€‹= â€‹486), in which we quantified the heritability of measures of cognitive functions, and tested whether they were driven by common genetic factors using pairwise genetic correlations. Subsequently, we derived activation maps associated with cognitive tasks via functional imaging meta-analysis in BrainMap (N â€‹= â€‹4484), and tested whether cognitive traits that shared genetic variation also exhibited overlapping brain activation. Our genetic analysis determined that six cognitive measures (cognitive flexibility, no-go continuous performance, fluid intelligence, processing speed, reading decoding and vocabulary comprehension) were heritable (0.3 â€‹< â€‹h2 â€‹< â€‹0.5), and genetically correlated with at least one other heritable cognitive measure (0.2 â€‹< â€‹ρg â€‹< â€‹0.35). The meta-analysis showed that two genetically-correlated traits, cognitive flexibility and fluid intelligence (ρg â€‹= â€‹0.24), also had a significant brain activation overlap (ρperm â€‹= â€‹0.29). These findings indicate that fluid intelligence and cognitive flexibility rely on overlapping biological features, both at the neural systems level and at the molecular level. The cross-disciplinary approach we introduce provides a concrete framework for data-driven quantification of biological convergence between genetics, brain function, and behavior in health and disease.


Asunto(s)
Cognición/fisiología , Función Ejecutiva/fisiología , Patrón de Herencia/genética , Inteligencia/genética , Adulto , Comprensión/fisiología , Conectoma , Femenino , Humanos , Masculino , Metaanálisis como Asunto , Tiempo de Reacción/genética , Adulto Joven
4.
Phys Rev Lett ; 124(8): 081803, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32167372

RESUMEN

We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26} e.cm.

5.
Behav Genet ; 49(3): 270-285, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30659475

RESUMEN

We aimed to detect Attention-deficit/hyperactivity (ADHD) risk-conferring genes in adults. In children, ADHD is characterized by age-inappropriate levels of inattention and/or hyperactivity-impulsivity and may persists into adulthood. Childhood and adulthood ADHD are heritable, and are thought to represent the clinical extreme of a continuous distribution of ADHD symptoms in the general population. We aimed to leverage the power of studies of quantitative ADHD symptoms in adults who were genotyped. Within the SAGA (Study of ADHD trait genetics in adults) consortium, we estimated the single nucleotide polymorphism (SNP)-based heritability of quantitative self-reported ADHD symptoms and carried out a genome-wide association meta-analysis in nine adult population-based and case-only cohorts of adults. A total of n = 14,689 individuals were included. In two of the SAGA cohorts we found a significant SNP-based heritability for self-rated ADHD symptom scores of respectively 15% (n = 3656) and 30% (n = 1841). The top hit of the genome-wide meta-analysis (SNP rs12661753; p-value = 3.02 × 10-7) was present in the long non-coding RNA gene STXBP5-AS1. This association was also observed in a meta-analysis of childhood ADHD symptom scores in eight population-based pediatric cohorts from the Early Genetics and Lifecourse Epidemiology (EAGLE) ADHD consortium (n = 14,776). Genome-wide meta-analysis of the SAGA and EAGLE data (n = 29,465) increased the strength of the association with the SNP rs12661753. In human HEK293 cells, expression of STXBP5-AS1 enhanced the expression of a reporter construct of STXBP5, a gene known to be involved in "SNAP" (Soluble NSF attachment protein) Receptor" (SNARE) complex formation. In mouse strains featuring different levels of impulsivity, transcript levels in the prefrontal cortex of the mouse ortholog Gm28905 strongly correlated negatively with motor impulsivity as measured in the five choice serial reaction time task (r2 = - 0.61; p = 0.004). Our results are consistent with an effect of the STXBP5-AS1 gene on ADHD symptom scores distribution and point to a possible biological mechanism, other than antisense RNA inhibition, involved in ADHD-related impulsivity levels.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Proteínas del Tejido Nervioso/genética , Proteínas R-SNARE/genética , ARN Largo no Codificante/genética , Adulto , Animales , Trastorno por Déficit de Atención con Hiperactividad/metabolismo , Estudios de Cohortes , ADN sin Sentido/genética , ADN sin Sentido/metabolismo , Femenino , Predisposición Genética a la Enfermedad/genética , Genética de Población/métodos , Estudio de Asociación del Genoma Completo , Genotipo , Células HEK293 , Humanos , Masculino , Ratones , Fenotipo , Polimorfismo de Nucleótido Simple/genética , ARN Largo no Codificante/metabolismo , Factores de Riesgo
6.
Mol Psychiatry ; 23(2): 257-262, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28242872

RESUMEN

Autism spectrum disorders (ASD) and attention-deficit/hyperactivity disorder (ADHD) frequently co-occur. The presence of a genetic link between ASD and ADHD symptoms is supported by twin studies, but the genetic overlap between clinically ascertained ASD and ADHD remains largely unclear. We therefore investigated how ASD and ADHD co-aggregate in individuals and in families to test for the presence of a shared genetic liability and examined potential differences between low- and high-functioning ASD in the link with ADHD. We studied 1 899 654 individuals born in Sweden between 1987 and 2006. Logistic regression was used to estimate the association between clinically ascertained ASD and ADHD in individuals and in families. Stratified estimates were obtained for ASD with (low-functioning) and without (high-functioning) intellectual disability. Individuals with ASD were at higher risk of having ADHD compared with individuals who did not have ASD (odds ratio (OR)=22.33, 95% confidence interval (CI): 21.77-22.92). The association was stronger for high-functioning than for low-functioning ASD. Relatives of individuals with ASD were at higher risk of ADHD compared with relatives of individuals without ASD. The association was stronger in monozygotic twins (OR=17.77, 95% CI: 9.80-32.22) than in dizygotic twins (OR=4.33, 95% CI: 3.21-5.85) and full siblings (OR=4.59, 95% CI: 4.39-4.80). Individuals with ASD and their relatives are at increased risk of ADHD. The pattern of association across different types of relatives supports the existence of genetic overlap between clinically ascertained ASD and ADHD, suggesting that genomic studies might have underestimated this overlap.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno del Espectro Autista/complicaciones , Trastorno del Espectro Autista/genética , Adolescente , Adulto , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Trastorno Autístico/complicaciones , Trastorno Autístico/genética , Niño , Preescolar , Estudios de Cohortes , Familia , Femenino , Estudios de Asociación Genética/métodos , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Sistema de Registros , Factores de Riesgo , Hermanos , Suecia , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética
7.
Mol Psychiatry ; 23(5): 1205-1212, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-28507316

RESUMEN

Autism spectrum disorders (ASDs) and autistic traits in the general population may share genetic susceptibility factors. In this study, we investigated such potential overlap based on common genetic variants. We developed and validated a self-report questionnaire of autistic traits in adults. We then conducted genome-wide association studies (GWASs) of six trait scores derived from the questionnaire through exploratory factor analysis in 1981 adults from the general population. Using the results from the Psychiatric Genomics Consortium GWAS of ASDs, we observed genetic sharing between ASDs and the autistic traits 'childhood behavior', 'rigidity' and 'attention to detail'. Gene-set analysis subsequently identified 'rigidity' to be significantly associated with a network of ASD gene-encoded proteins that regulates neurite outgrowth. Gene-wide association with the well-established ASD gene MET reached significance. Taken together, our findings provide evidence for an overlapping genetic and biological etiology underlying ASDs and autistic population traits, which suggests that genetic studies in the general population may yield novel ASD genes.


Asunto(s)
Trastorno del Espectro Autista/genética , Trastorno Autístico/genética , Adulto , Trastorno del Espectro Autista/etiología , Trastorno del Espectro Autista/fisiopatología , Trastorno Autístico/etiología , Trastorno Autístico/fisiopatología , Femenino , Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino , Fenotipo , Proteínas Proto-Oncogénicas c-met/genética , Autoinforme , Encuestas y Cuestionarios
8.
Nat Prod Rep ; 35(2): 137-146, 2018 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-29379937

RESUMEN

Covering: 1999 up to the end of 2017The small cyclic peptide SunFlower Trypsin Inhibitor-1 (SFTI-1) from sunflower seeds is the prototypic member of a novel family of natural products. The biosynthesis of these peptides is intriguing as their gene-encoded peptide backbone emerges from a precursor protein that also contains a seed storage albumin. The peptide sequence is cleaved out from the precursor and cyclised by the albumin-maturing enzymatic machinery. Three-dimensional solution NMR structures of a number of these peptides, and of the intact precursor protein preproalbumin with SFTI-1, have now been elucidated. Furthermore, the evolution of the family has been described and a detailed understanding of the biosynthetic steps, which are necessary to produce cyclic SFTI-1, is emerging. Macrocyclisation provides peptide stability and thus represents a key strategy in peptide drug development. Consequently the constrained structure of SFTI-1 has been explored as a template for protein engineering, for tuning selectivity towards clinically relevant proteases and for grafting in sequences with completely novel functions. Here we review the discovery of the SFTI-1 peptide family, their evolution, biosynthetic origin, and structural features, as well as highlight the potential applications of this unique class of natural products.


Asunto(s)
Péptidos Cíclicos/biosíntesis , Péptidos Cíclicos/química , Proteínas de Almacenamiento de Semillas/química , Albúminas/química , Antiinfecciosos/química , Antiinfecciosos/farmacología , Diseño de Fármacos , Evolución Molecular , Resonancia Magnética Nuclear Biomolecular , Péptidos Cíclicos/farmacología , Ingeniería de Proteínas/métodos , Proteínas de Almacenamiento de Semillas/biosíntesis , Proteínas de Almacenamiento de Semillas/genética , Inhibidores de Serina Proteinasa/química , Inhibidores de Serina Proteinasa/farmacología
10.
Mol Psychiatry ; 21(4): 565-73, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25962619

RESUMEN

Attention-deficit/hyperactivity disorder (ADHD) is a common, highly heritable neuropsychiatric disorder with hyperactivity as one of the hallmarks. Aberrant dopamine signaling is thought to be a major theme in ADHD, but how this relates to the vast majority of ADHD candidate genes is illusive. Here we report a Drosophila dopamine-related locomotor endophenotype that is shared by pan-neuronal knockdown of orthologs of the ADHD-associated genes Dopamine transporter (DAT1) and Latrophilin (LPHN3), and of a gene causing a monogenic disorder with frequent ADHD comorbidity: Neurofibromin (NF1). The locomotor signature was not found in control models and could be ameliorated by methylphenidate, validating its relevance to symptoms of the disorder. The Drosophila ADHD endophenotype can be further exploited in high throughput to characterize the growing number of candidate genes. It represents an equally useful outcome measure for testing chemical compounds to define novel treatment options.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno por Déficit de Atención con Hiperactividad/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Animales , Modelos Animales de Enfermedad , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Drosophila , Masculino , Metilfenidato/farmacología , Neurofibromina 1/genética , Neurofibromina 1/metabolismo , Receptores de Péptidos/genética , Receptores de Péptidos/metabolismo , Transducción de Señal
11.
Mol Psychiatry ; 21(9): 1202-7, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26573769

RESUMEN

A strong motivation for undertaking psychiatric gene discovery studies is to provide novel insights into unknown biology. Although attention-deficit hyperactivity disorder (ADHD) is highly heritable, and large, rare copy number variants (CNVs) contribute to risk, little is known about its pathogenesis and it remains commonly misunderstood. We assembled and pooled five ADHD and control CNV data sets from the United Kingdom, Ireland, United States of America, Northern Europe and Canada. Our aim was to test for enrichment of neurodevelopmental gene sets, implicated by recent exome-sequencing studies of (a) schizophrenia and (b) autism as a means of testing the hypothesis that common pathogenic mechanisms underlie ADHD and these other neurodevelopmental disorders. We also undertook hypothesis-free testing of all biological pathways. We observed significant enrichment of individual genes previously found to harbour schizophrenia de novo non-synonymous single-nucleotide variants (SNVs; P=5.4 × 10(-4)) and targets of the Fragile X mental retardation protein (P=0.0018). No enrichment was observed for activity-regulated cytoskeleton-associated protein (P=0.23) or N-methyl-D-aspartate receptor (P=0.74) post-synaptic signalling gene sets previously implicated in schizophrenia. Enrichment of ADHD CNV hits for genes impacted by autism de novo SNVs (P=0.019 for non-synonymous SNV genes) did not survive Bonferroni correction. Hypothesis-free testing yielded several highly significantly enriched biological pathways, including ion channel pathways. Enrichment findings were robust to multiple testing corrections and to sensitivity analyses that excluded the most significant sample. The findings reveal that CNVs in ADHD converge on biologically meaningful gene clusters, including ones now established as conferring risk of other neurodevelopmental disorders.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Psiquiatría Biológica/métodos , Adolescente , Trastorno Autístico/genética , Canadá , Niño , Preescolar , Variaciones en el Número de Copia de ADN/genética , Bases de Datos de Ácidos Nucleicos , Europa (Continente) , Femenino , Estudios de Asociación Genética/métodos , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Humanos , Irlanda , Masculino , Trastornos del Neurodesarrollo/genética , Polimorfismo de Nucleótido Simple/genética , Esquizofrenia/genética , Reino Unido
12.
J Wound Care ; 25(5): 256-65, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27169341

RESUMEN

OBJECTIVE: To evaluate the performance and safety of Mepilex Transfer Ag (MTAg) in the treatment of infected diabetic foot ulcers (DFU). METHOD: Patients with locally infected DFU were treated with the test dressing for up to 4 weeks, with a further 12 weeks of follow-up in a non-comparative study. Changes to wound infection and wound size as well as the condition of the peri-wound skin from baseline were assessed. Wound pain during dressing change was measured using a visual analogue scale (VAS). The investigators and patients documented their opinions on their overall experience of the test dressing and on key performance parameters. RESULTS: Following treatment with the test dressing, the signs and symptoms of local wound infection present in the target DFU were substantially reduced compared with baseline. Following the posttreatment evaluation, the majority of the DFU exhibited no signs of infection. and mean wound size was reduced by 50%. Wound size also continued to steadily decrease during follow-up. At the end of treatment five DFUs were completely healed and a further six healed by the end of the follow-up period. Concomitantly, over the course of the study, wound exudate levels were reduced and there was a significant improvement in the condition of the peri-wound area. Wound pain at dressing change was low throughout; generally patients felt no anxiety during the dressing change procedure. The patients considered it a comfortable dressing that remained in place and allowed ease of movement during wear. The investigating clinicians were highly satisfied with the overall performance, especially with respect to its ease of application and removal, conformability and flexibility. CONCLUSION: This study has demonstrated the potential of the dressing to provide topical antimicrobial activity directly to an infected DFU, suggesting prompt treatment of an infected DFU with this topical antimicrobial could aid wound complications. DECLARATION OF INTEREST: The authors have no conflict of interest to declare.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Vendajes , Pie Diabético/terapia , Siliconas , Compuestos de Plata/uso terapéutico , Infección de Heridas/terapia , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Exudados y Transudados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Satisfacción del Paciente , Estudios Prospectivos
13.
Ann Rheum Dis ; 74(3): e15, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24532677

RESUMEN

INTRODUCTION: Rheumatoid arthritis (RA) patients can be classified based on presence or absence of anticitrullinated peptide antibodies (ACPA) in their serum. This heterogeneity among patients may reflect important biological differences underlying the disease process. To date, the majority of genetic studies have focused on the ACPA-positive group. Therefore, our goal was to analyse the genetic risk factors that contribute to ACPA-negative RA. METHODS: We performed a large-scale genome-wide association study (GWAS) in three Caucasian European cohorts comprising 1148 ACPA-negative RA patients and 6008 controls. All patients were screened using the Illumina Human Cyto-12 chip, and controls were genotyped using different genome-wide platforms. Population-independent analyses were carried out by means of logistic regression. Meta-analysis with previously published data was performed as follow-up for selected signals (reaching a total of 1922 ACPA-negative RA patients and 7087 controls). Imputation of classical HLA alleles, amino acid residues and single nucleotide polymorphisms was undertaken. RESULTS: The combined analysis of the studied cohorts resulted in identification of a peak of association in the HLA-region and several suggestive non-HLA associations. Meta-analysis with previous reports confirmed the association of the HLA region with this subset and an observed association in the CLYBL locus remained suggestive. The imputation and deep interrogation of the HLA region led to identification of a two amino acid model (HLA-B at position 9 and HLA-DRB1 at position 11) that accounted for the observed genome-wide associations in this region. CONCLUSIONS: Our study shed light on the influence of the HLA region in ACPA-negative RA and identified a suggestive risk locus for this condition.


Asunto(s)
Artritis Reumatoide/genética , Antígenos HLA/genética , Alelos , Artritis Reumatoide/inmunología , Autoanticuerpos/inmunología , Estudios de Casos y Controles , Citrulina/inmunología , Estudio de Asociación del Genoma Completo , Antígenos HLA/inmunología , Antígenos HLA-B/genética , Cadenas HLA-DRB1/genética , Humanos , Modelos Logísticos , Péptidos/inmunología , Polimorfismo de Nucleótido Simple , Análisis de Componente Principal , Población Blanca/genética
14.
Phys Rev Lett ; 115(16): 162502, 2015 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-26550870

RESUMEN

We describe a spin-echo method for ultracold neutrons (UCNs) confined in a precession chamber and exposed to a |B0|=1 µT magnetic field. We have demonstrated that the analysis of UCN spin-echo resonance signals in combination with knowledge of the ambient magnetic field provides an excellent method by which to reconstruct the energy spectrum of a confined ensemble of neutrons. The method takes advantage of the relative dephasing of spins arising from a gravitationally induced striation of stored UCNs of different energies, and also permits an improved determination of the vertical magnetic-field gradient with an exceptional accuracy of 1.1 pT/cm. This novel combination of a well-known nuclear resonance method and gravitationally induced vertical striation is unique in the realm of nuclear and particle physics and should prove to be invaluable for the assessment of systematic effects in precision experiments such as searches for an electric dipole moment of the neutron or the measurement of the neutron lifetime.


Asunto(s)
Gravitación , Modelos Teóricos , Neutrones , Frío , Cinética
15.
Psychol Med ; 45(15): 3159-70, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26073896

RESUMEN

BACKGROUND: Impairment of response inhibition has been implicated in attention-deficit/hyperactivity disorder (ADHD). Dopamine neurotransmission has been linked to the behavioural and neural correlates of response inhibition. The current study aimed to investigate the relationship of polymorphisms in two dopamine-related genes, the catechol-O-methyltransferase gene (COMT) and the dopamine transporter gene (SLC6A3 or DAT1), with the neural and behavioural correlates of response inhibition. METHOD: Behavioural and neural measures of response inhibition were obtained in 185 adolescents with ADHD, 111 of their unaffected siblings and 124 healthy controls (mean age 16.9 years). We investigated the association of DAT1 and COMT variants on task performance and whole-brain neural activation during response inhibition in a hypothesis-free manner. Additionally, we attempted to explain variance in previously found ADHD effects on neural activation during response inhibition using these DAT1 and COMT polymorphisms. RESULTS: The whole-brain analyses demonstrated large-scale neural activation changes in the medial and lateral prefrontal, subcortical and parietal regions of the response inhibition network in relation to DAT1 and COMT polymorphisms. Although these neural activation changes were associated with different task performance measures, no relationship was found between DAT1 or COMT variants and ADHD, nor did variants in these genes explain variance in the effects of ADHD on neural activation. CONCLUSIONS: These results suggest that dopamine-related genes play a role in the neurobiology of response inhibition. The limited associations between gene polymorphisms and task performance further indicate the added value of neural measures in linking genetic factors and behavioural measures.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/genética , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Encéfalo/fisiopatología , Catecol O-Metiltransferasa/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Inhibición Psicológica , Desempeño Psicomotor/fisiología , Adolescente , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Hermanos
16.
Mol Psychiatry ; 19(4): 452-61, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23568192

RESUMEN

Bipolar disorder (BD) is a polygenic disorder that shares substantial genetic risk factors with major depressive disorder (MDD). Genetic analyses have reported numerous BD susceptibility genes, while some variants, such as single-nucleotide polymorphisms (SNPs) in CACNA1C have been successfully replicated, many others have not and subsequently their effects on the intermediate phenotypes cannot be verified. Here, we studied the MDD-related gene CREB1 in a set of independent BD sample groups of European ancestry (a total of 64,888 subjects) and identified multiple SNPs significantly associated with BD (the most significant being SNP rs6785[A], P=6.32 × 10(-5), odds ratio (OR)=1.090). Risk SNPs were then subjected to further analyses in healthy Europeans for intermediate phenotypes of BD, including hippocampal volume, hippocampal function and cognitive performance. Our results showed that the risk SNPs were significantly associated with hippocampal volume and hippocampal function, with the risk alleles showing a decreased hippocampal volume and diminished activation of the left hippocampus, adding further evidence for their involvement in BD susceptibility. We also found the risk SNPs were strongly associated with CREB1 expression in lymphoblastoid cells (P<0.005) and the prefrontal cortex (P<1.0 × 10(-6)). Remarkably, population genetic analysis indicated that CREB1 displayed striking differences in allele frequencies between continental populations, and the risk alleles were completely absent in East Asian populations. We demonstrated that the regional prevalence of the CREB1 risk alleles in Europeans is likely caused by genetic hitchhiking due to natural selection acting on a nearby gene. Our results suggest that differential population histories due to natural selection on regional populations may lead to genetic heterogeneity of susceptibility to complex diseases, such as BD, and explain inconsistencies in detecting the genetic markers of these diseases among different ethnic populations.


Asunto(s)
Trastorno Bipolar/etnología , Trastorno Bipolar/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Regulación de la Expresión Génica/genética , Predisposición Genética a la Enfermedad , Hipocampo/patología , Polimorfismo de Nucleótido Simple/genética , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Pueblo Asiatico/genética , Estudios de Casos y Controles , Biología Computacional , Femenino , Frecuencia de los Genes/genética , Estudios de Asociación Genética , Humanos , Masculino , Persona de Mediana Edad , Neuroimagen , Pruebas Neuropsicológicas , Fenotipo , ARN Mensajero/metabolismo , Población Blanca/genética
17.
Eur J Clin Microbiol Infect Dis ; 34(2): 331-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25213718

RESUMEN

Direct treatment costs caused by candidemia in German intensive care unit (ICU) patients are currently unknown. We analyzed treatment costs and the impact of antifungal drug choice. Comprehensive data of patients who had at least one episode of candidemia while staying in the ICU between 01/2005 and 12/2010 were documented in a database using the technology of the Cologne Cohort of Neutropenic Patients (CoCoNut). A detailed analysis of all disease-associated treatment costs was performed. Patients treated with echinocandins (i.e., anidulafungin, caspofungin, micafungin) or fluconazole were analyzed separately and compared. Forty-one and 64 patients received echinocandins and fluconazole, respectively. The mean Acute Physiology and Chronic Health Evaluation (APACHE) IV score was 114 (95 % confidence interval [CI]: 106-122) vs. 95 (95 % CI: 90-101, p = <0.001). Twenty-three (56 %) and 33 (52 %, p = 0.448) patients survived hospitalization, while 17 (41 %) and 22 (34 %, p = 0.574) survived one year after diagnosis. In the echinocandin and fluconazole groups, the mean costs per patient of ICU treatment were 20,338 (95 % CI: 12,893-27,883) vs. 11,932 (95 % CI: 8,016-15,849, p = 0.110), and the total direct treatment costs per patient were 37,995 (95 % CI: 26,614-49,376) vs. 22,305 (95 % CI: 16,817-27,793, p = 0.012), resulting in daily costs per patient of 1,158 (95 % CI: 1,036-1,280) vs. 927 (95 % CI: 828-1,026, p = 0.001). Our health economic analysis shows the high treatment costs of patients with candidemia in the ICU. Sicker patients had a prolonged hospitalization and were more likely to receive echinocandins, leading to higher treatment costs. Outcomes were comparable to those achieved in less sick patients with fluconazole.


Asunto(s)
Antifúngicos/uso terapéutico , Candidemia/tratamiento farmacológico , Equinocandinas/uso terapéutico , Fluconazol/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anidulafungina , Candidemia/economía , Caspofungina , Niño , Preescolar , Femenino , Costos de la Atención en Salud , Hospitalización/economía , Humanos , Lactante , Unidades de Cuidados Intensivos , Lipopéptidos/uso terapéutico , Masculino , Micafungina , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
18.
Infection ; 43(6): 707-14, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26123227

RESUMEN

PURPOSE: Clostridium difficile associated diarrhoea (CDAD) is the most common cause of health-care-associated infectious diarrhoea. In the context of the German health-care system, direct and indirect costs of an initial episode of CDAD and of CDAD recurrence are currently unknown. METHODS: We defined CDAD as presence of diarrhoea (≥3 unformed stools/day) in association with detection of Clostridium difficile toxin in an unformed faecal sample. Patients treated with metronidazole (PO or IV) and/or vancomycin (PO) were included. Comprehensive data of patients were retrospectively documented into a database using the technology of the Cologne Cohort of Neutropenic Patients (CoCoNut). Patients with CDAD were matched to control patients in a 1:1 ratio. Analysis was split in three groups: incidence group (CDAD patients without recurrence), recurrence group (CDAD patients with ≥1 recurrence) and control group (matched non-CDAD patients). RESULTS: Between 02/2010 and 12/2011, 150 patients with CDAD (114 patients in the incidence and 36 (24 %) in the recurrence group) and 150 controls were analysed. Mean length of stay was: 32 (95 %CI: 30-37), 94 (95 %CI: 76-112) and 24 days (95 %CI: 22-27; P = <0.001), resulting in mean overall direct treatment costs per patient of €18,460 (95 %CI: €14,660-€22,270), €73,900 (95 %CI: €50,340-€97,460) and €14,530 (95 %CI: €11,730-€17,330; P = <0.001). In the incidence and recurrence group, the mean cumulative number of antibiotic CDAD treatment days was 11 (95 %CI: 10-12) and 36 (95 %CI: 27-45; P = <0.001). CONCLUSIONS: Especially CDAD recurrence was associated with excessive costs, which were mostly attributable to a significantly longer overall length of stay. Innovative treatment strategies are warranted to reduce treatment costs and prevent recurrence of CDAD.


Asunto(s)
Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/economía , Costo de Enfermedad , Diarrea/economía , Adulto , Anciano , Anciano de 80 o más Años , Infecciones por Clostridium/epidemiología , Infecciones por Clostridium/microbiología , Diarrea/epidemiología , Diarrea/microbiología , Femenino , Alemania/epidemiología , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Centros de Atención Terciaria , Adulto Joven
19.
Eur Child Adolesc Psychiatry ; 24(8): 959-68, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25395383

RESUMEN

Meta-analyses suggest normalizing effects of methylphenidate on structural fronto-striatal abnormalities in patients with attention-deficit/hyperactivity disorder (ADHD). A subgroup of patients receives atypical antipsychotics concurrent with methylphenidate. Long-term safety and efficacy of combined treatment are unknown. The current study provides an initial investigation of structural brain correlates of combined methylphenidate and antipsychotic treatment in patients with ADHD. Structural magnetic resonance imaging was obtained in 31 patients who had received combined methylphenidate and antipsychotic treatment, 31 matched patients who had received methylphenidate but not antipsychotics, and 31 healthy controls (M age 16.7 years). We analyzed between-group effects in total cortical and subcortical volume, and in seven frontal cortical and eight subcortical-limbic volumes of interest, each involved in dopaminergic neurotransmission. Patients in the combined treatment group, but not those in the methylphenidate only group, showed a reduction in total cortical volume compared to healthy controls (Cohen's d = 0.69, p < 0.004), which was apparent in most frontal volumes of interest. Further, the combined treatment group, but not the methylphenidate group, showed volume reduction in bilateral ventral diencephalon (Left Cohen's d = 0.48, p < 0.04; Right Cohen's d = 0.46, p < 0.05) and the left thalamus (Cohen's d = 0.47, p < 0.04). These findings may indicate antipsychotic treatment counteracting the normalizing effects of methylphenidate on brain structure. However, it cannot be ruled out that pre-existing clinical differences between both patient groups may have resulted in anatomical differences at the time of scanning. The absence of an untreated ADHD group hinders unequivocal interpretation and implications of our findings.


Asunto(s)
Antipsicóticos/uso terapéutico , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Encéfalo/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/uso terapéutico , Imagen por Resonancia Magnética/métodos , Metilfenidato/uso terapéutico , Administración Oral , Adolescente , Atención , Trastorno por Déficit de Atención con Hiperactividad/patología , Encéfalo/metabolismo , Encéfalo/patología , Estudios de Casos y Controles , Cuerpo Estriado/efectos de los fármacos , Estudios Transversales , Quimioterapia Combinada , Femenino , Humanos , Masculino , Resultado del Tratamiento
20.
Psychol Med ; 44(4): 881-92, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23721667

RESUMEN

BACKGROUND: The results of twin and sibling studies suggest that executive functioning is a prime candidate endophenotype in attention deficit hyperactivity disorder (ADHD). However, studies have not assessed the co-segregation of executive function (EF) deficits from parents to offspring directly, and it is unclear whether executive functioning is an ADHD endophenotype in adolescents, given the substantial changes in prefrontal lobe functioning, EF and ADHD symptoms during adolescence. METHOD: We recruited 259 ADHD and 98 control families with an offspring average age of 17.3 years. All participants were assessed for ADHD and EF [inhibition, verbal (VWM) and visuospatial working memory (VsWM)]. Data were analysed using generalized estimating equations (GEEs). RESULTS: Parental ADHD was associated with offspring ADHD and parental EF was associated with offspring EF but there were no cross-associations (parental ADHD was not associated with offspring EF or vice versa). Similar results were found when siblings were compared. EF deficits were only found in affected adolescents and not in their unaffected siblings or (un)affected parents. CONCLUSIONS: The core EFs proposed to be aetiologically related to ADHD, that is working memory and inhibition, seem to be aetiologically independent of ADHD in adolescence. EF deficits documented in childhood in unaffected siblings were no longer present in adolescence, suggesting that children 'grow out' of early EF deficits. This is the first study to document ADHD and EF in a large family sample with adolescent offspring. The results suggest that, after childhood, the majority of influences on ADHD are independent from those on EF. This has potential implications for current aetiological models of causality in ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Endofenotipos , Función Ejecutiva/fisiología , Padres/psicología , Adolescente , Adulto , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Trastorno por Déficit de Atención con Hiperactividad/etiología , Niño , Femenino , Humanos , Inhibición Psicológica , Masculino , Memoria a Corto Plazo/fisiología , Persona de Mediana Edad , Países Bajos/epidemiología , Hermanos/psicología , Adulto Joven
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