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1.
Mol Psychiatry ; 28(3): 1240-1247, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36517639

RESUMO

While childhood attention-deficit/hyperactivity disorder (ADHD) is more prevalent in males than females, genetic contributors to this effect have not been established. Here, we explore sex differences in the contribution of common and/or rare genetic variants to ADHD. Participants were from the Adolescent Brain and Cognitive Development study (N = 1253 youth meeting DSM-5 criteria for ADHD [mean age = 11.46 years [SD = 0.87]; 31% female] and 5577 unaffected individuals [mean age = 11.42 years [SD = 0.89]; 50% female], overall 66% White, non-Hispanic (WNH), 19% Black/African American, and 15% other races. Logistic regression tested for interactions between sex (defined genotypically) and both rare copy number variants (CNV) and polygenic (common variant) risk in association with ADHD. There was a significant interaction between sex and the presence of a CNV deletion larger than 200 kb, both in the entire cohort (ß = -0.74, CI = [-1.27 to -0.20], FDR-corrected p = 0.048) and, at nominal significance levels in the WNH ancestry subcohort (ß = -0.86, CI = [-1.51 to -0.20], p = 0.010). Additionally, the number of deleted genes interacted with sex in association with ADHD (whole cohort. ß = -0.13, CI = [-0.23 to -0.029], FDR-corrected p = 0.048; WNH. ß = -0.17, CI = [-0.29 to -0.050], FDR-corrected p = 0.044) as did the total length of CNV deletions (whole cohort. ß = -0.12, CI = [-0.19 to -0.044], FDR-corrected p = 0.028; WNH. ß = -0.17, CI = [-0.28 to -0.061], FDR-corrected p = 0.034). This sex effect was driven by increased odds of childhood ADHD for females but not males in the presence of CNV deletions. No similar sex effect was found for CNV duplications or polygenic risk scores. The association between CNV deletions and ADHD was partially mediated by measures of cognitive flexibility. In summary, CNV deletions were associated with increased odds for childhood ADHD in females, but not males.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Adolescente , Humanos , Masculino , Feminino , Criança , Transtorno do Deficit de Atenção com Hiperatividade/genética , Variações do Número de Cópias de DNA , Predisposição Genética para Doença , Encéfalo , Grupos Raciais
2.
Mol Psychiatry ; 28(2): 792-800, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36380233

RESUMO

Despite advances in identifying rare and common genetic variants conferring risk for ADHD, the lack of a transcriptomic understanding of cortico-striatal brain circuitry has stymied a molecular mechanistic understanding of this disorder. To address this gap, we mapped the transcriptome of the caudate nucleus and anterior cingulate cortex in post-mortem tissue from 60 individuals with and without ADHD. Significant differential expression of genes was found in the anterior cingulate cortex and, to a lesser extent, the caudate. Significant downregulation emerged of neurotransmitter gene pathways, particularly glutamatergic, in keeping with models that implicate these neurotransmitters in ADHD. Consistent with the genetic overlap between mental disorders, correlations were found between the cortico-striatal transcriptomic changes seen in ADHD and those seen in other neurodevelopmental and mood disorders. This transcriptomic evidence points to cortico-striatal neurotransmitter anomalies in the pathogenesis of ADHD, consistent with current models of the disorder.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Transcriptoma/genética , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Corpo Estriado/metabolismo , Encéfalo/metabolismo
3.
Psychol Med ; 53(2): 524-532, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132649

RESUMO

BACKGROUND: Recommendations for promoting mental health during the COVID-19 pandemic include maintaining social contact, through virtual rather than physical contact, moderating substance/alcohol use, and limiting news and media exposure. We seek to understand if these pandemic-related behaviors impact subsequent mental health. METHODS: Daily online survey data were collected on adults during May/June 2020. Measures were of daily physical and virtual (online) contact with others; substance and media use; and indices of psychological striving, struggling and COVID-related worry. Using random-intercept cross-lagged panel analysis, dynamic within-person cross-lagged effects were separated from more static individual differences. RESULTS: In total, 1148 participants completed daily surveys [657 (57.2%) females, 484 (42.1%) males; mean age 40.6 (s.d. 12.4) years]. Daily increases in news consumed increased COVID-related worrying the next day [cross-lagged estimate = 0.034 (95% CI 0.018-0.049), FDR-adjusted p = 0.00005] and vice versa [0.03 (0.012-0.048), FDR-adjusted p = 0.0017]. Increased media consumption also exacerbated subsequent psychological struggling [0.064 (0.03-0.098), FDR-adjusted p = 0.0005]. There were no significant cross-lagged effects of daily changes in social distancing or virtual contact on later mental health. CONCLUSIONS: We delineate a cycle wherein a daily increase in media consumption results in a subsequent increase in COVID-related worries, which in turn increases daily media consumption. Moreover, the adverse impact of news extended to broader measures of psychological struggling. A similar dynamic did not unfold between the daily amount of physical or virtual contact and subsequent mental health. Findings are consistent with current recommendations to moderate news and media consumption in order to promote mental health.


Assuntos
COVID-19 , Adulto , Feminino , Masculino , Humanos , Saúde Mental , Pandemias , Consumo de Bebidas Alcoólicas , Etanol
4.
Cereb Cortex ; 32(14): 3031-3041, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35848863

RESUMO

Homophily refers to the tendency to like similar others. Here, we ask if homophily extends to brain structure. Specifically: do children who like one another have more similar brain structures? We hypothesized that neuroanatomic similarity tied to friendship is most likely to pertain to brain regions that support social cognition. To test this hypothesis, we analyzed friendship network data from 1186 children in 49 classrooms. Within each classroom, we identified "friendship distance"-mutual friends, friends-of-friends, and more distantly connected or unconnected children. In total, 125 children (mean age = 7.57 years, 65 females) also had good quality neuroanatomic magnetic resonance imaging scans from which we extracted properties of the "social brain." We found that similarity of the social brain varied by friendship distance: mutual friends showed greater similarity in social brain networks compared with friends-of-friends (ß = 0.65, t = 2.03, P = 0.045) and even more remotely connected peers (ß = 0.77, t = 2.83, P = 0.006); friends-of-friends did not differ from more distantly connected peers (ß = -0.13, t = -0.53, P = 0.6). We report that mutual friends have similar "social brain" networks, adding a neuroanatomic dimension to the adage that "birds of a feather flock together."


Assuntos
Amigos , Grupo Associado , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Imageamento por Ressonância Magnética , Rede Social
5.
J Transl Med ; 20(1): 124, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287669

RESUMO

BACKGROUND: Chimeric antigen receptor (CAR) T-cell therapy has proven to be a valuable new treatment option for patients with B-cell malignancies. However, by applying selective pressure, outgrowth of antigen-negative tumor cells can occur, eventually resulting in relapse. Subsequent rescue by administration of CAR-T cells with different antigen-specificity indicates that those tumor cells are still sensitive to CAR-T treatment and points towards a multi-target strategy. Due to their natural tumor sensitivity and highly cytotoxic nature, natural killer (NK) cells are a compelling alternative to T cells, especially considering the availability of an off-the-shelf unlimited supply in the form of the clinically validated NK-92 cell line. METHODS: Given our goal to develop a flexible system whereby the CAR expression repertoire of the effector cells can be rapidly adapted to the changing antigen expression profile of the target cells, electrotransfection with CD19-/BCMA-CAR mRNA was chosen as CAR loading method in this study. We evaluated the functionality of mRNA-engineered dual-CAR NK-92 against tumor B-cell lines and primary patient samples. In order to test the clinical applicability of the proposed cell therapy product, the effect of irradiation on the proliferative rate and functionality of dual-CAR NK-92 cells was investigated. RESULTS: Co-electroporation of CD19 and BMCA CAR mRNA was highly efficient, resulting in 88.1% dual-CAR NK-92 cells. In terms of CD107a degranulation, and secretion of interferon (IFN)-γ and granzyme B, dual-CAR NK-92 significantly outperformed single-CAR NK-92. More importantly, the killing capacity of dual-CAR NK-92 exceeded 60% of single and dual antigen-expressing cell lines, as well as primary tumor cells, in a 4h co-culture assay at low effector to target ratios, matching that of single-CAR counterparts. Furthermore, our results confirm that dual-CAR NK-92 irradiated with 10 Gy cease to proliferate and are gradually cleared while maintaining their killing capacity. CONCLUSIONS: Here, using the clinically validated NK-92 cell line as a therapeutic cell source, we established a readily accessible and flexible platform for the generation of highly functional dual-targeted CAR-NK cells.


Assuntos
Antígeno de Maturação de Linfócitos B , Receptores de Antígenos Quiméricos , Antígeno de Maturação de Linfócitos B/metabolismo , Citotoxicidade Imunológica , Humanos , Imunoterapia Adotiva/métodos , Células Matadoras Naturais , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo
6.
Mol Psychiatry ; 26(8): 4046-4054, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33173195

RESUMO

Childhood attention deficit hyperactivity disorder (ADHD) shows a highly variable course with age: some individuals show improving, others stable or worsening symptoms. The ability to predict symptom course could help individualize treatment and guide interventions. By studying a cohort of 362 youth, we ask if polygenic risk for ADHD, combined with baseline neural and cognitive features could aid in the prediction of the course of symptoms over an average period of 4.8 years. Compared to a never-affected comparison group, we find that participants with worsening symptoms carried the highest polygenic risk for ADHD, followed by those with stable symptoms, then those whose symptoms improved. Participants with worsening symptoms also showed atypical baseline cognition. Atypical microstructure of the cingulum bundle and anterior thalamic radiation was associated with improving symptoms while reduction of thalamic volume was found in those with stable symptoms. Machine-learning algorithms, trained and tested on independent groups, performed well in classifying those never affected against groups with worsening, stable, and improving symptoms (area under the curve >0.79). We conclude that some measures of polygenic risk, cognition, and neuroimaging show significant associations with the future course of ADHD symptoms and may have modest predictive power. These features warrant further exploration as prognostic tools.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Substância Branca , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/genética , Cognição , Genômica , Humanos , Herança Multifatorial/genética
7.
Malar J ; 21(1): 302, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36303209

RESUMO

BACKGROUND: The resistance of Plasmodium falciparum to artemisinin-based (ART) drugs, the front-line drug family used in artemisinin-based combination therapy (ACT) for treatment of malaria, is of great concern. Mutations in the kelch13 (k13) gene (for example, those resulting in the Cys580Tyr [C580Y] variant) were identified as genetic markers for ART-resistant parasites, which suggests they are associated with resistance mechanisms. However, not all resistant parasites contain a k13 mutation, and clearly greater understanding of resistance mechanisms is required. A genome-wide association study (GWAS) found single nucleotide polymorphisms associated with ART-resistance in fd (ferredoxin), arps10 (apicoplast ribosomal protein S10), mdr2 (multidrug resistance protein 2), and crt (chloroquine resistance transporter), in addition to k13 gene mutations, suggesting that these alleles contribute to the resistance phenotype. The importance of the FD and ARPS10 variants in ART resistance was then studied since both proteins likely function in the apicoplast, which is a location distinct from that of K13. METHODS: The reported mutations were introduced, together with a mutation to produce the k13-C580Y variant into the ART-sensitive 3D7 parasite line and the effect on ART-susceptibility using the 0-3 h ring survival assay (RSA0-3 h) was investigated. RESULTS AND CONCLUSION: Introducing both fd-D193Y and arps10-V127M into a k13-C580Y-containing parasite, but not a wild-type k13 parasite, increased survival of the parasite in the RSA0-3 h. The results suggest epistasis of arps10 and k13, with arps10-V127M a modifier of ART susceptibility in different k13 allele backgrounds.


Assuntos
Antimaláricos , Apicoplastos , Artemisininas , Malária Falciparum , Humanos , Plasmodium falciparum , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Malária Falciparum/parasitologia , Apicoplastos/metabolismo , Estudo de Associação Genômica Ampla , Resistência a Medicamentos/genética , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Mutação
8.
BMC Public Health ; 22(1): 1777, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36123662

RESUMO

BACKGROUND: Recent research has shown the mental health consequence of social distancing during the COVID-19 pandemic, but longitudinal data are relatively scarce. It is unclear whether the pattern of isolation and elevated stress seen at the beginning of the pandemic persists over time. This study evaluates change in social interaction over six months and its impact on emotional wellbeing among older adults. METHODS: We drew data from a panel study with six repeated assessments of social interaction and emotional wellbeing conducted monthly May through October 2020. The sample included a total of 380 White, Black and Hispanic participants aged 50 and over, of whom 33% had low income, who residing in fourteen U.S. states with active stay-at-home orders in May 2020. The analysis examined how change in living arrangement, in-person interaction outside the household, quality of relationship with family and friends, and perceived social support affected trajectories of isolation stress, COVID worry and sadness. RESULTS: While their living arrangements (Odds Ratio [OR] = 0.95, 95% Confidence Interval [CI] = 0.87, 1.03) and relationship quality (OR = 0.94, 95% CI = 0.82, 1.01) remained stable, older adults experienced fluctuations in perceived social support (linear Slope b = -1.42, s.e. = 0.16, p < .001, quadratic slope b = 0.50, s.e. = 0.08, p < .001, cubic slope b = -0.04, s.e. = 0.01, p < .001) and increases in in-person conversations outside the household (OR = 1.19, 95% CI = 1.09, 1.29). Living with a spouse/partner stabilized isolation stress (change in linear slope b = 1.16, s.e. = 0.48, p < .05, in quadratic slope b = -0.62, s.e. = 0.26, p < .05, and in cubic slope = 0.09, s.e. = 0.04, p < .05) and COVID worry (change in quadratic slope b = -0.66, s.e. = 0.32, p < .05 and in cubic slope = 0.09, s.e. = 0.04, p < .05) over time. Individuals with better relationship quality with friends had decreased sadness over time (OR = 0.90, 95% CI = 0.82, 0.99). Changes in social support were associated with greater fluctuations in isolation stress and COVID worry. CONCLUSIONS: During the pandemic, social interactions are protective and lack of stability in feeling supported makes older adults vulnerable to stress. Efforts should focus on (re)building and maintaining companionship and support to mitigate the pandemic's negative impact.


Assuntos
COVID-19 , Interação Social , Idoso , COVID-19/epidemiologia , Emoções , Humanos , Pessoa de Meia-Idade , Pandemias , Apoio Social , Estados Unidos/epidemiologia
9.
Child Psychiatry Hum Dev ; 53(6): 1330-1339, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34184159

RESUMO

Assessing stability and change of children's psychopathology symptoms can help elucidate whether specific behaviors are transient developmental variations or indicate persistent psychopathology. This study included 6930 children across early childhood (T1), late childhood (T2) and early adolescence (T3), from the general population. Latent profile analysis identified psychopathology subgroups and latent transition analysis quantified the probability that children remained within, or transitioned across psychopathology subgroups. We identified four psychopathology subgroups; no problems (T1: 85.9%, T2: 79.0%, T3: 78.0%), internalizing (T1: 5.1%, T2: 9.2%, T3: 9.0%), externalizing (T1: 7.3%, T2: 8.3%, T3: 10.2%) and the dysregulation profile (DP) (T1: 1.7%, T2: 3.5%, T3: 2.8%). From T1 to T2, 44.7% of the children remained in the DP. Between T2 and T3, 33.6% remained in the DP; however, 91.4% were classified in one of the psychopathology subgroups. Our findings suggest that for many children, internalizing or externalizing symptoms encompass a transient phase within development. Contrary, the DP resembles a severe at-risk state in which the predictive value for being in one of the psychopathology subgroups increases over time.


Assuntos
Transtornos do Comportamento Infantil , Psicopatologia , Adolescente , Criança , Comportamento Infantil , Transtornos do Comportamento Infantil/diagnóstico , Pré-Escolar , Humanos
10.
Molecules ; 27(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458660

RESUMO

The treatment of a variety of protozoal infections, in particular those causing disabling human diseases, is still hampered by a lack of drugs or increasing resistance to registered drugs. However, in recent years, remarkable progress has been achieved to combat neglected tropical diseases by sequencing the parasites' genomes or the validation of new targets in the parasites by novel genetic manipulation techniques, leading to loss of function. The novel amino acid hypusine is a posttranslational modification (PTM) that occurs in eukaryotic initiation factor 5A (EIF5A) at a specific lysine residue. This modification occurs by two steps catalyzed by deoxyhypusine synthase (dhs) and deoxyhypusine hydroxylase (DOHH) enzymes. dhs from Plasmodium has been validated as a druggable target by small molecules and reverse genetics. Recently, the synthesis of a series of human dhs inhibitors led to 6-bromo-N-(1H-indol-4yl)-1-benzothiophene-2-carboxamide, a potent allosteric inhibitor with an IC50 value of 0.062 µM. We investigated this allosteric dhs inhibitor in Plasmodium. In vitro P. falciparum growth assays showed weak inhibition activity, with IC50 values of 46.1 µM for the Dd2 strain and 51.5 µM for the 3D7 strain, respectively. The antimalarial activity could not be attributed to the targeting of the Pfdhs gene, as shown by chemogenomic profiling with transgenically modified P. falciparum lines. Moreover, in dose-dependent enzymatic assays with purified recombinant P. falciparum dhs protein, only 45% inhibition was observed at an inhibitor dose of 0.4 µM. These data are in agreement with a homology-modeled Pfdhs, suggesting significant structural differences in the allosteric site between the human and parasite enzymes. Virtual screening of the allosteric database identified candidate ligand binding to novel binding pockets identified in P. falciparum dhs, which might foster the development of parasite-specific inhibitors.


Assuntos
Oxirredutases atuantes sobre Doadores de Grupo CH-NH , Plasmodium , Inibidores Enzimáticos/farmacologia , Humanos , Oxigenases de Função Mista/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/antagonistas & inibidores , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Plasmodium/metabolismo , Proteínas Recombinantes/metabolismo , Tiofenos/farmacologia
11.
Clin Genet ; 100(6): 703-712, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34496037

RESUMO

To maximize the potential of genomics in medicine, it is essential to establish databases of genomic variants for ethno-geographic groups that can be used for filtering and prioritizing candidate pathogenic variants. Populations with non-European ancestry are poorly represented among current genomic variant databases. Here, we report the first high-density survey of genomic variants for the Thai population, the Thai Reference Exome (T-REx) variant database. T-REx comprises exome sequencing data of 1092 unrelated Thai individuals. The targeted exome regions common among four capture platforms cover 30.04 Mbp on autosomes and chromosome X. 345 681 short variants (18.27% of which are novel) and 34 907 copy number variations were found. Principal component analysis on 38 469 single nucleotide variants present worldwide showed that the Thai population is most genetically similar to East and Southeast Asian populations. Moreover, unsupervised clustering revealed six Thai subpopulations consistent with the evidence of gene flow from neighboring populations. The prevalence of common pathogenic variants in T-REx was investigated in detail, which revealed subpopulation-specific patterns, in particular variants associated with erythrocyte disorders such as the HbE variant in HBB and the Viangchan variant in G6PD. T-REx serves as a pivotal addition to the current databases for genomic medicine.


Assuntos
Bases de Dados Genéticas , Exoma , Variação Genética , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Estudos de Associação Genética/métodos , Predisposição Genética para Doença , Genética Populacional , Medicina Genômica/métodos , Humanos , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Tailândia , Sequenciamento do Exoma
12.
Mol Psychiatry ; 25(10): 2482-2492, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-30700802

RESUMO

There are now large-scale data on which common genetic variants confer risk for attention deficit hyperactivity disorder (ADHD). Here, we use mediation analyses to explore how cognitive and neural features might explain the association between common variant (polygenic) risk for ADHD and its core symptoms. In total, 544 participants participated (mean 21 years, 212 (39%) with ADHD), most with cognitive assessments, neuroanatomic imaging, and imaging of white matter tract microstructure. We found that polygenic risk for ADHD was associated with symptoms of hyperactivity-impulsivity but not inattention. This association was mediated across multiple PRS thresholds by white matter microstructure, specifically by axial diffusivity of the right corona radiata, (maximum indirect effect ß = -0.034 (CI: -0.065 to -0.01), by thickness of the left dorsomedial prefrontal (ß = -0.029; CI: -0.061 to -0.0047) and area of the right lateral temporal cortex (ß = 0.024; CI: 0.0034-0.054). In addition, modest serial mediation was found, mapping a pathway from polygenic risk, to white matter microstructure of the anterior corona radiata, then cognition (working memory, focused attention), and finally to hyperactivity-impulsivity (working memory ß = -0.014 (CI: -0.038 to -0.0026); focused attention ß = -0.011 (CI: -0.033 to -0.0017). These mediation pathways were diagnostically specific and were not found for polygenic risk for ASD or schizophrenia. In conclusion, using a deeply phenotyped cohort, we delineate a pathway from polygenic risk for ADHD to hyperactive-impulsive symptoms through white matter microstructure, cortical anatomy, and cognition.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Encéfalo , Cognição , Predisposição Genética para Doença , Transtornos Mentais , Herança Multifatorial , Adulto , Criança , Feminino , Humanos , Masculino , Transtorno do Deficit de Atenção com Hiperatividade/genética , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Comportamento Impulsivo , Transtornos Mentais/genética , Herança Multifatorial/genética , Substância Branca/diagnóstico por imagem
13.
Nature ; 511(7511): 587-91, 2014 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-25043043

RESUMO

During the blood stages of malaria, several hundred parasite-encoded proteins are exported beyond the double-membrane barrier that separates the parasite from the host cell cytosol. These proteins have a variety of roles that are essential to virulence or parasite growth. There is keen interest in understanding how proteins are exported and whether common machineries are involved in trafficking the different classes of exported proteins. One potential trafficking machine is a protein complex known as the Plasmodium translocon of exported proteins (PTEX). Although PTEX has been linked to the export of one class of exported proteins, there has been no direct evidence for its role and scope in protein translocation. Here we show, through the generation of two parasite lines defective for essential PTEX components (HSP101 or PTEX150), and analysis of a line lacking the non-essential component TRX2 (ref. 12), greatly reduced trafficking of all classes of exported proteins beyond the double membrane barrier enveloping the parasite. This includes proteins containing the PEXEL motif (RxLxE/Q/D) and PEXEL-negative exported proteins (PNEPs). Moreover, the export of proteins destined for expression on the infected erythrocyte surface, including the major virulence factor PfEMP1 in Plasmodium falciparum, was significantly reduced in PTEX knockdown parasites. PTEX function was also essential for blood-stage growth, because even a modest knockdown of PTEX components had a strong effect on the parasite's capacity to complete the erythrocytic cycle both in vitro and in vivo. Hence, as the only known nexus for protein export in Plasmodium parasites, and an essential enzymic machine, PTEX is a prime drug target.


Assuntos
Proteínas de Choque Térmico/metabolismo , Malária/parasitologia , Plasmodium falciparum/genética , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Proteínas de Choque Térmico/genética , Humanos , Estágios do Ciclo de Vida/fisiologia , Complexos Multiproteicos/metabolismo , Transporte Proteico/genética , Proteínas de Protozoários/genética , Vacúolos/metabolismo , Vacúolos/parasitologia
14.
Proc Natl Acad Sci U S A ; 114(44): 11787-11792, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29078281

RESUMO

We have a limited understanding of why many children with attention deficit hyperactivity disorder do not outgrow the disorder by adulthood. Around 20-30% retain the full syndrome as young adults, and about 50% show partial, rather than complete, remission. Here, to delineate the neurobiology of this variable outcome, we ask if the persistence of childhood symptoms into adulthood impacts on the brain's functional connectivity. We studied 205 participants followed clinically since childhood. In early adulthood, participants underwent magnetoencephalography (MEG) to measure neuronal activity directly and functional MRI (fMRI) to measure hemodynamic activity during a task-free period (the "resting state"). We found that symptoms of inattention persisting into adulthood were associated with disrupted patterns of typical functional connectivity in both MEG and fMRI. Specifically, those with persistent inattention lost the typical balance of connections within the default mode network (DMN; prominent during introspective thought) and connections between this network and those supporting attention and cognitive control. By contrast, adults whose childhood inattentive symptoms had resolved did not differ significantly from their never-affected peers, both hemodynamically and electrophysiologically. The anomalies in functional connectivity tied to clinically significant inattention centered on midline regions of the DMN in both MEG and fMRI, boosting confidence in a possible pathophysiological role. The findings suggest that the clinical course of this common childhood onset disorder impacts the functional connectivity of the adult brain.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Encéfalo/fisiopatologia , Rede Nervosa/fisiopatologia , Adulto , Atenção/fisiologia , Mapeamento Encefálico/métodos , Transtornos Cognitivos/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Magnetoencefalografia/métodos , Masculino , Imagem Multimodal/métodos , Vias Neurais/fisiopatologia , Adulto Jovem
15.
Genet Epidemiol ; 42(4): 405-414, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29682794

RESUMO

Genome-wide association studies (GWASs) are unraveling the genetics of adult brain neuroanatomy as measured by cross-sectional anatomic magnetic resonance imaging (aMRI). However, the genetic mechanisms that shape childhood brain development are, as yet, largely unexplored. In this study we identify common genetic variants associated with childhood brain development as defined by longitudinal aMRI. Genome-wide single nucleotide polymorphism (SNP) data were determined in two cohorts: one enriched for attention-deficit/hyperactivity disorder (ADHD) (LONG cohort: 458 participants; 119 with ADHD) and the other from a population-based cohort (Generation R: 257 participants). The growth of the brain's major regions (cerebral cortex, white matter, basal ganglia, and cerebellum) and one region of interest (the right lateral prefrontal cortex) were defined on all individuals from two aMRIs, and a GWAS and a pathway analysis were performed. In addition, association between polygenic risk for ADHD and brain growth was determined for the LONG cohort. For white matter growth, GWAS meta-analysis identified a genome-wide significant intergenic SNP (rs12386571, P = 9.09 × 10-9 ), near AKR1B10. This gene is part of the aldo-keto reductase superfamily and shows neural expression. No enrichment of neural pathways was detected and polygenic risk for ADHD was not associated with the brain growth phenotypes in the LONG cohort that was enriched for the diagnosis of ADHD. The study illustrates the use of a novel brain growth phenotype defined in vivo for further study.


Assuntos
Encéfalo/crescimento & desenvolvimento , Estudo de Associação Genômica Ampla , Adolescente , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/genética , Criança , Estudos de Coortes , Estudos Transversais , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Herança Multifatorial/genética , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Substância Branca/patologia
16.
Psychol Med ; 49(4): 590-597, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-29792238

RESUMO

BACKGROUND: While the neuroanatomic substrates of symptoms of attention deficit hyperactivity disorder (ADHD) have been investigated, less is known about the neuroanatomic correlates of cognitive abilities pertinent to the disorder, particularly in adults. Here we define the neuroanatomic correlates of key cognitive abilities and determine if there are associations with histories of psychostimulant medication. METHODS: We acquired neuroanatomic magnetic resonance imaging data from 264 members of 60 families (mean age 29.5; s.d. 18.4, 116 with ADHD). Using linear mixed model regression, we tested for associations between cognitive abilities (working memory, information processing, intelligence, and attention), symptoms and both cortical and subcortical volumes. RESULTS: Symptom severity was associated with spatial working memory (t = -3.77, p = 0.0002), processing speed (t = -2.95, p = 0.004) and a measure of impulsive responding (t = 2.19, p = 0.03); these associations did not vary with age (all p > 0.1). Neuroanatomic associations of cognition varied by task but centered on prefrontal, lateral parietal and temporal cortical regions, the thalamus and putamen. The neuroanatomic correlates of ADHD symptoms overlapped significantly with those of working memory (Dice's overlap coefficient: spatial, p = 0.003; verbal, p = 0.001) and information processing (p = 0.02). Psychostimulant medication history was associated with neither cognitive skills nor with a brain-cognition relationships. CONCLUSIONS: Diagnostic differences in the cognitive profile of ADHD does not vary significantly with age; nor were cognitive differences associated with psychostimulant medication history. The neuroanatomic substrates of working memory and information overlapped with those for symptoms within these extended families, consistent with a pathophysiological role for these cognitive skills in familial ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/patologia , Mapeamento Encefálico , Encéfalo/patologia , Cognição , Adulto , Atenção , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Criança , Família , Feminino , Humanos , Inteligência , Imageamento por Ressonância Magnética , Masculino , Memória de Curto Prazo , Neuroimagem , Testes Neuropsicológicos , Índice de Gravidade de Doença
17.
Hum Brain Mapp ; 39(3): 1218-1231, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29206318

RESUMO

Motion-related artifacts are one of the major challenges associated with pediatric neuroimaging. Recent studies have shown a relationship between visual quality ratings of T1 images and cortical reconstruction measures. Automated algorithms offer more precision in quantifying movement-related artifacts compared to visual inspection. Thus, the goal of this study was to test three different automated quality assessment algorithms for structural MRI scans. The three algorithms included a Fourier-, integral-, and a gradient-based approach which were run on raw T1 -weighted imaging data collected from four different scanners. The four cohorts included a total of 6,662 MRI scans from two waves of the Generation R Study, the NIH NHGRI Study, and the GUSTO Study. Using receiver operating characteristics with visually inspected quality ratings of the T1 images, the area under the curve (AUC) for the gradient algorithm, which performed better than either the integral or Fourier approaches, was 0.95, 0.88, and 0.82 for the Generation R, NHGRI, and GUSTO studies, respectively. For scans of poor initial quality, repeating the scan often resulted in a better quality second image. Finally, we found that even minor differences in automated quality measurements were associated with FreeSurfer derived measures of cortical thickness and surface area, even in scans that were rated as good quality. Our findings suggest that the inclusion of automated quality assessment measures can augment visual inspection and may find use as a covariate in analyses or to identify thresholds to exclude poor quality data.


Assuntos
Artefatos , Imageamento por Ressonância Magnética , Reconhecimento Automatizado de Padrão , Garantia da Qualidade dos Cuidados de Saúde/métodos , Algoritmos , Área Sob a Curva , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Movimento (Física) , Tamanho do Órgão , Reconhecimento Automatizado de Padrão/métodos , Curva ROC
18.
J Child Psychol Psychiatry ; 59(10): 1114-1123, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29693267

RESUMO

BACKGROUND: The cerebellum supports many cognitive functions disrupted in attention deficit hyperactivity disorder (ADHD). Prior neuroanatomic studies have been often limited by small sample sizes, inconsistent findings, and a reliance on cross-sectional data, limiting inferences about cerebellar development. Here, we conduct a multicohort study using longitudinal data, to characterize cerebellar development. METHODS: Growth trajectories of the cerebellar vermis, hemispheres and white matter were estimated using piecewise linear regression from 1,656 youth; of whom 63% had longitudinal data, totaling 2,914 scans. Four cohorts participated, all contained childhood data (age 4-12 years); two had adolescent data (12-25 years). Growth parameters were combined using random-effects meta-analysis. RESULTS: Diagnostic differences in growth were confined to the corpus medullare (cerebellar white matter). Here, the ADHD group showed slower growth in early childhood compared to the typically developing group (left corpus medullare z = 2.49, p = .01; right z = 2.03, p = .04). This reversed in late childhood, with faster growth in ADHD in the left corpus medullare (z = 2.06, p = .04). Findings held when gender, intelligence, comorbidity, and psychostimulant medication were considered. DISCUSSION: Across four independent cohorts, containing predominately longitudinal data, we found diagnostic differences in the growth of cerebellar white matter. In ADHD, slower white matter growth in early childhood was followed by faster growth in late childhood. The findings are consistent with the concept of ADHD as a disorder of the brain's structural connections, formed partly by developing cortico-cerebellar white matter tracts.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Cerebelo/crescimento & desenvolvimento , Cerebelo/fisiopatologia , Neuroimagem , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Estudos Longitudinais , Masculino , Países Baixos , Adulto Jovem
19.
J Psychiatry Neurosci ; 43(2): 170094, 2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29402375

RESUMO

BACKGROUND: There is evidence suggesting neuropsychiatric disorders share genomic, cognitive and clinical features. Here, we ask if autism-spectrum disorders (ASD), attention-deficit/hyperactivity disorder (ADHD) and schizophrenia share neuroanatomical variations. METHODS: First, we used measures of cortical anatomy to estimate spatial overlap of neuroanatomical variation using univariate methods. Next, we developed a novel methodology to determine whether cortical deficits specifically target or are "enriched" within functional resting-state networks. RESULTS: We found cortical anomalies were preferentially enriched across functional networks rather than clustering spatially. Specifically, cortical thickness showed significant enrichment between patients with ASD and those with ADHD in the default mode network, between patients with ASD and those with schizophrenia in the frontoparietal and limbic networks, and between patients with ADHD and those with schizophrenia in the ventral attention network. Networks enriched in cortical thickness anomalies were also strongly represented in functional MRI results (Neurosynth; r = 0.64, p = 0.032). LIMITATIONS: We did not account for variable symptom dimensions and severity in patient populations, and our cross-sectional design prevented longitudinal analyses of developmental trajectories. CONCLUSION: These findings suggest that common deficits across neuropsychiatric disorders cannot simply be characterized as arising out of local changes in cortical grey matter, but rather as entities of both local and systemic alterations targeting brain networks.

20.
J Psychiatry Neurosci ; 43(3): 201-212, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29688876

RESUMO

BACKGROUND: There is evidence suggesting neuropsychiatric disorders share genomic, cognitive and clinical features. Here, we ask if autism-spectrum disorders (ASD), attention-deficit/hyperactivity disorder (ADHD) and schizophrenia share neuroanatomical variations. METHODS: First, we used measures of cortical anatomy to estimate spatial overlap of neuroanatomical variation using univariate methods. Next, we developed a novel methodology to determine whether cortical deficits specifically target or are "enriched" within functional resting-state networks. RESULTS: We found cortical anomalies were preferentially enriched across functional networks rather than clustering spatially. Specifically, cortical thickness showed significant enrichment between patients with ASD and those with ADHD in the default mode network, between patients with ASD and those with schizophrenia in the frontoparietal and limbic networks, and between patients with ADHD and those with schizophrenia in the ventral attention network. Networks enriched in cortical thickness anomalies were also strongly represented in functional MRI results (Neurosynth; r = 0.64, p = 0.032). LIMITATIONS: We did not account for variable symptom dimensions and severity in patient populations, and our cross-sectional design prevented longitudinal analyses of developmental trajectories. CONCLUSION: These findings suggest that common deficits across neuropsychiatric disorders cannot simply be characterized as arising out of local changes in cortical grey matter, but rather as entities of both local and systemic alterations targeting brain networks.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno Autístico/patologia , Córtex Cerebral/patologia , Esquizofrenia/patologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno Autístico/fisiopatologia , Córtex Cerebral/fisiopatologia , Estudos Transversais , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Neuroimagem , Fenótipo , Esquizofrenia/fisiopatologia
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