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Cancer cells are in most instances characterized by rapid proliferation and uncontrolled cell division. Hence, they must adapt to proliferation-induced metabolic stress through intrinsic or acquired antimetabolic stress responses to maintain homeostasis and survival. One mechanism to achieve this is reprogramming gene expression in a metabolism-dependent manner. MondoA (also known as Myc-associated factor X-like protein X-interacting protein [MLXIP]), a member of the MYC interactome, has been described as an example of such a metabolic sensor. However, the role of MondoA in malignancy is not fully understood and the underlying mechanism in metabolic responses remains elusive. By assessing patient data sets, we found that MondoA overexpression is associated with worse survival in pediatric common acute lymphoblastic leukemia (ALL; B-precursor ALL [B-ALL]). Using clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) and RNA-interference approaches, we observed that MondoA depletion reduces the transformational capacity of B-ALL cells in vitro and dramatically inhibits malignant potential in an in vivo mouse model. Interestingly, reduced expression of MondoA in patient data sets correlated with enrichment in metabolic pathways. The loss of MondoA correlated with increased tricarboxylic acid cycle activity. Mechanistically, MondoA senses metabolic stress in B-ALL cells by restricting oxidative phosphorylation through reduced pyruvate dehydrogenase activity. Glutamine starvation conditions greatly enhance this effect and highlight the inability to mitigate metabolic stress upon loss of MondoA in B-ALL. Our findings give novel insight into the function of MondoA in pediatric B-ALL and support the notion that MondoA inhibition in this entity offers a therapeutic opportunity and should be further explored.
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Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas de Neoplasias/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/metabolismo , Estresse Fisiológico , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Proteínas de Neoplasias/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genéticaRESUMO
BACKGROUND: Prenatal alcohol exposure (PAE) has been linked to severe, adverse child outcomes. However, little is known regarding subclinical outcomes of low/moderate PAE and its longitudinal consequences, especially regarding neurophysiological and neurocognitive development. A newborn biomarker of PAE, meconium ethyl glucuronide (EtG), has been shown to predict cognitive impairments in primary-school-aged children. The current study investigated the ongoing effects of subclinical PAE in adolescence. METHODS: A sample of n = 96 mother-child dyads of the FRAMES/FRANCES cohort were classified into PAE/no PAE using EtG with a 10 ng/g cutoff. Mothers were recruited during pregnancy and children were assessed during primary-school age (M = 7.57, SD = 0.65, range: 6.00-9.92 years) and adolescence (M = 13.26, SD = 0.31, range: 12.79-14.20 years) on three levels: clinical (ADHD rating), neuropsychological (IQ score and performance in a go/nogo task), and neurophysiological (analysis of P3 event-related potentials (ERP) during said go/nogo task). Developmental outcomes and courses following PAE were assessed using rmANCOVAs, controlling for relevant confounders (socioeconomic status (SES), birth weight, and maternal psychopathology). RESULTS: Neurophysiological impairments emerged for exposed children in the form of diminished attentional resource recruiting in childhood and adolescence (reduced go-P3 amplitudes) with no differences in performance. Neuropsychological testing showed a reduced IQ score for both time points with dose-dependent effects in childhood. Clinical ADHD symptoms were not significantly affected. CONCLUSION: Subclinical PAE, as determined by meconium EtG, has negative developmental consequences on cognitive function that persist from childhood to adolescence. These findings suggest that there is no safe limit for alcohol consumption during pregnancy and that more thorough screening of alcohol consumption during pregnancy is necessary for early identification and treatment of at-risk children.
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Glucuronatos , Mecônio , Efeitos Tardios da Exposição Pré-Natal , Recém-Nascido , Humanos , Feminino , Adolescente , Gravidez , Criança , Efeitos Tardios da Exposição Pré-Natal/diagnóstico , Etanol , Consumo de Bebidas Alcoólicas/efeitos adversos , CogniçãoRESUMO
In this Article, author Benedikt Brors was erroneously associated with affiliation number '8' (Department of Developmental Neurobiology, St Jude Children's Research Hospital, Memphis, Tennessee, USA); the author's two other affiliations (affiliations '3' and '7', both at the German Cancer Research Center (DKFZ)) were correct. This has been corrected online.
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Pan-cancer analyses that examine commonalities and differences among various cancer types have emerged as a powerful way to obtain novel insights into cancer biology. Here we present a comprehensive analysis of genetic alterations in a pan-cancer cohort including 961 tumours from children, adolescents, and young adults, comprising 24 distinct molecular types of cancer. Using a standardized workflow, we identified marked differences in terms of mutation frequency and significantly mutated genes in comparison to previously analysed adult cancers. Genetic alterations in 149 putative cancer driver genes separate the tumours into two classes: small mutation and structural/copy-number variant (correlating with germline variants). Structural variants, hyperdiploidy, and chromothripsis are linked to TP53 mutation status and mutational signatures. Our data suggest that 7-8% of the children in this cohort carry an unambiguous predisposing germline variant and that nearly 50% of paediatric neoplasms harbour a potentially druggable event, which is highly relevant for the design of future clinical trials.
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Genoma Humano/genética , Genômica , Mutação/genética , Neoplasias/classificação , Neoplasias/genética , Adolescente , Adulto , Criança , Cromotripsia , Estudos de Coortes , Variações do Número de Cópias de DNA/genética , Diploide , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa/genética , Humanos , Terapia de Alvo Molecular , Taxa de Mutação , Neoplasias/tratamento farmacológico , Proteína Supressora de Tumor p53/genética , Adulto JovemRESUMO
The pterin-dependent nonheme iron enzymes hydroxylate aromatic amino acids to perform the biosynthesis of neurotransmitters to maintain proper brain function. These enzymes activate oxygen using a pterin cofactor and an aromatic amino acid substrate bound to the FeII active site to form a highly reactive FeIV = O species that initiates substrate oxidation. In this study, using tryptophan hydroxylase, we have kinetically generated a pre-FeIV = O intermediate and characterized its structure as a FeII-peroxy-pterin species using absorption, Mössbauer, resonance Raman, and nuclear resonance vibrational spectroscopies. From parallel characterization of the pterin cofactor and tryptophan substrate-bound ternary FeII active site before the O2 reaction (including magnetic circular dichroism spectroscopy), these studies both experimentally define the mechanism of FeIV = O formation and demonstrate that the carbonyl functional group on the pterin is directly coordinated to the FeII site in both the ternary complex and the peroxo intermediate. Reaction coordinate calculations predict a 14 kcal/mol reduction in the oxygen activation barrier due to the direct binding of the pterin carbonyl to the FeII site, as this interaction provides an orbital pathway for efficient electron transfer from the pterin cofactor to the iron center. This direct coordination of the pterin cofactor enables the biological function of the pterin-dependent hydroxylases and demonstrates a unified mechanism for oxygen activation by the cofactor-dependent nonheme iron enzymes.
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Ferro/metabolismo , Neurotransmissores/biossíntese , Proteínas Nucleares/metabolismo , Pterinas/química , Proteína Gli2 com Dedos de Zinco/metabolismo , Humanos , Ferro/química , Proteínas Nucleares/química , Oxigênio/metabolismo , Pterinas/metabolismo , Triptofano/química , Triptofano/metabolismo , Proteína Gli2 com Dedos de Zinco/químicaRESUMO
BACKGROUND: Anorexia nervosa (AN) is associated with altered processing of disorder-relevant stimuli. Event-related potentials (ERP) - such as the Late Positive Potential (LPP) - give information about the underlying mechanisms of central nervous stimulus processing. METHODS: Patients with AN (22 adolescents, 23 adults) and healthy controls (HCs; 17 adolescents, 24 adults) were included. Neutral, low, and high calorie food-images were rated for valence and arousal; EEG activity was recorded and LPPs (early: 350-700 ms; late: 800-1200 ms) were extracted. Effects of patient status, age group, and stimulus category were analyzed via mixed 2 × 2 × 3-AN(C)OVAs. RESULTS: Patients with AN rated high calorie stimuli lower in valence and higher in arousal than HCs. Controlling for hunger, food stimuli elicited higher early LPPs than neutral ones in patients and HCs. For the late LPP, patients with AN showed larger amplitudes. CONCLUSION: Results suggest a highly automatic attentional bias towards low-calorie foods. Patients with AN seem to have more intense cognitive processing independent of stimulus material. More research is needed to validate and clarify differences between early and late LPP measures as well as the operationalization and relevance of hunger status.
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Anorexia Nervosa , Eletroencefalografia , Adulto , Humanos , Adolescente , Emoções/fisiologia , Anorexia Nervosa/psicologia , Potenciais Evocados/fisiologia , AlimentosRESUMO
OBJECTIVE: An increasing demand for inpatient treatment for adolescents with anorexia nervosa (AN) during and after the Covid-19 pandemic contrasts with limited capacity and long waiting times. The current pilot study evaluated an outpatient group therapy (GT) as early intervention for adolescents with AN prior to inpatient treatment. METHODS: Seventeen female adolescents who participated at the GT (intervention group, INT) were compared to 16 adolescents without GT (treatment-as-usual, TAU). BMI, eating disorder psychopathology and motivation of change (MoC) were assessed at three timepoints. RESULTS: Comparing pre- versus post- group participation, we identified a significant increase of MoC and a trend towards a decreased AN-specific psychopathology. Comparing INT with TAU adolescents, we found a significant lower AN psychopathology at inpatient admission for the INT group and a trend for different BMI courses: While the BMI of the TAU group decreased during waiting time, the INT group did not show a decrease during GT resulting in a higher BMI at admission. CONCLUSIONS: Results of the current pilot study suggest positive effects of an early outpatient intervention in a group setting for adolescents with AN prior to inpatient treatment. Further research with larger sample sizes is necessary to validate the current pilot results.
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While α-, ß-, and γ-cyclodextrin (CD) are ubiquitous hosts employed by supramolecular chemists, δ-CD (formed from nine α-1,4-linked glucopyranose units) has received very little attention. α-, ß-, and γ-CD are the major products of the enzymatic breakdown of starch by cyclodextrin glucanotransferase (CGTase), but δ-CD forms only transiently in this reaction, as a minor component of a complex mixture of linear and cyclic glucans. In this work, we show how δ-CD can be synthesized in unprecedented yields by employing a bolaamphiphile template in an enzyme-mediated dynamic combinatorial library of cyclodextrins. NMR spectroscopy studies revealed that δ-CD can thread up to three bolaamphiphiles forming [2]-, [3]-, or [4]-pseudorotaxanes, depending on the size of the hydrophilic headgroup and the length of the alkyl chain axle. Threading of the first bolaamphiphile occurs in fast exchange on the NMR chemical shift time scale, while subsequent threading occurs in slow exchange. To extract quantitative information for 1:2 and 1:3 binding events occurring in mixed exchange regimes, we derived equations for nonlinear curve fitting that take into consideration both the chemical shift changes for species in fast exchange and the integrals for species in slow exchange to determine Ka1, Ka2, and Ka3. Template T1 could be used to direct the enzymatic synthesis of δ-CD due to the cooperative formation of a 1:2 complexâthe [3]-pseudorotaxane δ-CD·T12. Importantly, T1 is recyclable. It can be readily recovered from the enzymatic reaction by precipitation and reused in subsequent syntheses enabling preparative-scale synthesis of δ-CD.
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Ciclodextrinas , Ciclodextrinas/química , Glucanos , Amido/química , Glucosiltransferases/metabolismoRESUMO
Therapeutic proteins can be challenging to develop due to their complexity and the requirement of an acceptable formulation to ensure patient safety and efficacy. To date, there is no universal formulation development strategy that can identify optimal formulation conditions for all types of proteins in a fast and reliable manner. In this work, high-throughput characterization, employing a toolbox of five techniques, was performed on 14 structurally different proteins formulated in 6 different buffer conditions and in the presence of 4 different excipients. Multivariate data analysis and chemometrics were used to analyze the data in an unbiased way. First, observed changes in stability were primarily determined by the individual protein. Second, pH and ionic strength are the two most important factors determining the physical stability of proteins, where there exists a significant statistical interaction between protein and pH/ionic strength. Additionally, we developed prediction methods by partial least-squares regression. Colloidal stability indicators are important for prediction of real-time stability, while conformational stability indicators are important for prediction of stability under accelerated stress conditions at 40 °C. In order to predict real-time storage stability, protein-protein repulsion and the initial monomer fraction are the most important properties to monitor.
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Anticorpos Monoclonais , Quimiometria , Humanos , Estabilidade Proteica , Anticorpos Monoclonais/química , Desdobramento de Proteína , Conformação Proteica , Estabilidade de MedicamentosRESUMO
To fully understand animal transcription networks, it is essential to accurately measure the spatial and temporal expression patterns of transcription factors and their targets. We describe a registration technique that takes image-based data from hundreds of Drosophila blastoderm embryos, each costained for a reference gene and one of a set of genes of interest, and builds a model VirtualEmbryo. This model captures in a common framework the average expression patterns for many genes in spite of significant variation in morphology and expression between individual embryos. We establish the method's accuracy by showing that relationships between a pair of genes' expression inferred from the model are nearly identical to those measured in embryos costained for the pair. We present a VirtualEmbryo containing data for 95 genes at six time cohorts. We show that known gene-regulatory interactions can be automatically recovered from this data set and predict hundreds of new interactions.
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Drosophila melanogaster/genética , Redes Reguladoras de Genes , Modelos Genéticos , Animais , Blastoderma , Drosophila melanogaster/metabolismo , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genes de InsetosRESUMO
Determining the requirements for efficient oxygen (O2) activation is key to understanding how enzymes maintain efficacy and mitigate unproductive, often detrimental reactivity. For the α-ketoglutarate (αKG)-dependent nonheme iron enzymes, both a concerted mechanism (both cofactor and substrate binding prior to reaction with O2) and a sequential mechanism (cofactor binding and reaction with O2 precede substrate binding) have been proposed. Deacetoxycephalosporin C synthase (DAOCS) is an αKG-dependent nonheme iron enzyme for which both of these mechanisms have been invoked to generate an intermediate that catalyzes oxidative ring expansion of penicillin substrates in cephalosporin biosynthesis. Spectroscopy shows that, in contrast to other αKG-dependent enzymes (which are six coordinate when only αKG is bound to the FeII), αKG binding to FeII-DAOCS results in â¼45% five-coordinate sites that selectively react with O2 relative to the remaining six-coordinate sites. However, this reaction produces an FeIII species that does not catalyze productive ring expansion. Alternatively, simultaneous αKG and substrate binding to FeII-DAOCS produces five-coordinate sites that rapidly react with O2 to form an FeIV=O intermediate that then reacts with substrate to produce cephalosporin product. These results demonstrate that the concerted mechanism is operative in DAOCS and by extension, other nonheme iron enzymes.
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Transferases Intramoleculares/química , Ferro/química , Ácidos Cetoglutáricos/química , Ferroproteínas não Heme/química , Proteínas de Ligação às Penicilinas/química , Espécies Reativas de Oxigênio/química , Ativação Enzimática , Oxirredução , Penicilina G/química , Especificidade por SubstratoRESUMO
The sirtuins are NAD+ -dependent lysine deacylases, comprising seven isoforms (SIRT1-7) in humans, which are involved in the regulation of a plethora of biological processes, including gene expression and metabolism. The sirtuins share a common hydrolytic mechanism but display preferences for different ϵ-N-acyllysine substrates. SIRT7 deacetylates targets in nuclei and nucleoli but remains one of the lesser studied of the seven isoforms, in part due to a lack of chemical tools to specifically probe SIRT7 activity. Here we expressed SIRT7 and, using small-angle X-ray scattering, reveal SIRT7 to be a monomeric enzyme with a low degree of globular flexibility in solution. We developed a fluorogenic assay for investigation of the substrate preferences of SIRT7 and to evaluate compounds that modulate its activity. We report several mechanism-based SIRT7 inhibitors as well as de novo cyclic peptide inhibitors selected from mRNA-display library screening that exhibit selectivity for SIRT7 over other sirtuin isoforms, stabilize SIRT7 in cells, and cause an increase in the acetylation of H3 K18.
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Sirtuína 1 , Sirtuínas , Humanos , Sirtuína 1/metabolismo , Sirtuínas/química , Acetilação , Hidrólise , Isoformas de Proteínas/metabolismoRESUMO
Conformational stability of human serum transferrin (Tf) at varying pH values and salt and excipient concentrations were investigated using molecular dynamics (MD) simulations, and the results are compared with previously published small-angle X-ray scattering (SAXS) experiments. SAXS study showed that at pH 5, Tf is predominantly present in a partially open (PO) form, and the factions of PO differ based on the physicochemical condition and drift toward the closed form (HO) as the pH increases. Tf is a bilobal glycoprotein that is composed of homologous halves termed the N- and C-lobes. The current study shows that the protonation of Y188 and K206 at pH 5 is the primary conformational drive into PO, which shifts toward the closed (HO) conformer as the pH increases. Furthermore, at pH 6.5, PO is unfavorable due to negative charge-charge repulsion at the N/C-lobe interface linker region causing increased hinge distance when compared to HO, which has favorable attractive electrostatic interactions in this region. Subsequently, the effect of salt concentration was studied at 70 and 140 mM NaCl. At 70 mM NaCl and pH 5, chloride ions bind strongly in the N-lobe iron-binding site, whereas these interactions are weak at pH 6.5. With increasing salt concentration at pH 5, the regions surrounding the N-lobe iron-binding site are saturated, and as a consequence, sodium and chloride ions accumulate into the bulk. Additionally, protein-excipient interactions were investigated. At pH 5, the excipients interact in similar loop regions, E89-T93, and D416-D420, located in the N- and C-lobes of the HO conformer, respectively. It is anticipated that interactions of additives in these two loop regions cause conformational changes that lead to iron-coordinating residues in the N-lobe to drift away from iron and thus drive HO to PO conversion. Furthermore, at pH 6.5 and 140 mM histidine, these interactions are negligible leading to the stabilization of HO.
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Simulação de Dinâmica Molecular , Transferrina , Cloretos , Excipientes , Humanos , Concentração de Íons de Hidrogênio , Ferro/metabolismo , Conformação Proteica , Espalhamento a Baixo Ângulo , Cloreto de Sódio , Transferrina/metabolismo , Difração de Raios XRESUMO
Using light scattering (LS), small-angle X-ray scattering (SAXS), and coarse-grained Monte Carlo (MC) simulations, we studied the self-interactions of two monoclonal antibodies (mAbs), PPI03 and PPI13. With LS measurements, we obtained the osmotic second virial coefficient, B22, and the molecular weight, Mw, of the two mAbs, while with SAXS measurements, we studied the mAbs' self-interaction behavior in the high protein concentration regime up to 125 g/L. Through SAXS-derived coarse-grained representations of the mAbs, we performed MC simulations with either a one-protein or a two-protein model to predict B22. By comparing simulation and experimental results, we validated our models and obtained insights into the mAbs' self-interaction properties, highlighting the role of both ion binding and charged patches on the mAb surfaces. Our models provide useful information about mAbs' self-interaction properties and can assist the screening of conditions driving to colloidal stability.
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Anticorpos Monoclonais , Anticorpos Monoclonais/química , Método de Monte Carlo , Espalhamento a Baixo Ângulo , Difração de Raios X , Raios XRESUMO
BACKGROUND: Perinatal markers of prenatal development are associated with offspring psychiatric symptoms. However, there is little research investigating the specificity of perinatal markers for the development of specific disorders. This study aimed to explore if perinatal markers are specifically associated with adolescent substance use disorder (SUDs). METHODS: Adolescent participants from two study centers, one for SUD patients (n = 196) and one for general psychopathology (n = 307), were recruited for participation. Since the SUD participants presented with a number of comorbid disorders, we performed a 1-on-1 matching procedure, based on age, gender, and specific pattern of comorbid disorders. This procedure resulted in n = 51 participants from each group. From all participants and their mothers we recorded perinatal markers (mode of birth, weeks of completed pregnancy, birth weight, Apgar score after 5 min) as well as intelligence quotient (IQ). The SUD sample additionally filled out the Youth Safe Report (YSR) as well as the PQ-16 and the DUDIT. We aimed to distinguish the two groups (SUD sample vs. general psychiatric sample) based on the perinatal variables via a logistic regression analysis. Additionally, linear regressions were performed for the total group and the subgroups to assess the relationship between perinatal variables and IQ, YSR, DUDIT and PQ-16. RESULTS: The perinatal variables were not able to predict group membership (X2 [4] = 4.77, p = .312, Cox & Snell R² = 0.053). Odds ratios indicated a small increase in probability to belonging to the general psychiatric sample instead of the SUD sample if birth was completed via C-section. After Bonferroni-correction, the linear regression models showed no relation between perinatal markers and IQ (p = .60, R² = 0.068), YSR (p = .09, R² = 0.121), DUDIT (p = .65, R² = 0.020), and PQ-16 (p = .73, R² =0.021). CONCLUSION: Perinatal markers were not able to distinguish SUD patients from patients with diverse psychopathologies. This pattern contradicts previous findings, perhaps because our chosen markers reflect general processes instead of specific mechanistic explanations. Future studies should take care to investigate specific prenatal markers and associate them with psychopathology on the symptom level.
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Saúde Mental , Transtornos Relacionados ao Uso de Substâncias , Gravidez , Feminino , Adolescente , Humanos , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Psicopatologia , PartoRESUMO
Maternal depression and child development: A prospective analysis of consequences, risk and protective factors Abstract. Objective: Maternal stress, specifically maternal mental health problems, are considered risk factors for child development. The literature suggests that prenatal depressive symptoms as well as depressive symptoms are a widespread phenomenon during the further development of the child and have repeatedly been shown to have adverse effects on child mental health outcomes. The present study examined the longitudinal relationships between maternal depression (prenatal, postnatal, during childhood and adolescence) and child mental health from childhood to adolescence. Possible risk and protective factors were also considered. Method: N = 112 mothers were assessed for depressive symptoms via a questionnaire at four different timepoints (prenatal, T1; postnatal, T2; during childhood, T3; during adolescence, T4). Children's externalizing and internalizing symptoms (50.9 % girls) were assessed by their mothers both during childhood (M = 7.68, SD = 0.76 years) and during adolescence (M = 13.23, SD = 0.27 years). We evaluated the relationships between maternal depressive symptoms and children's externalizing/internalizing symptoms using multiple regression models and analyzed possible risk and protective factors using moderation analysis. Results: Externalizing/Internalizing symptoms were not directly associated with maternal depressive symptoms, while associations between such symptoms and maladaptive behavior were found in adolescents. The socioeconomic status of families showed a different risk profile for prenatal and postnatal depressive symptoms. The IQ of the children proved to be a risk factor for internalizing symptoms. Conclusions: Maternal depressive symptoms at any time during child development - in combination with further risk factors - have an impact on child mental health. The early identification of maternal symptoms followed by interventions to differentiate between prenatal and postnatal depression - especially in the context of socioeconomic status - are highly relevant for child development.
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Depressão Pós-Parto , Depressão , Adolescente , Criança , Desenvolvimento Infantil , Depressão/psicologia , Depressão Pós-Parto/diagnóstico , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia , Feminino , Humanos , Masculino , Mães/psicologia , Gravidez , Fatores de ProteçãoRESUMO
BACKGROUND: Drinking alcohol during pregnancy is considered a risk factor for child development; however, child biomarkers of prenatal alcohol exposure have been rarely studied. We examined whether a meconium alcohol metabolite (ethyl glucuronide, EtG) was associated with child cortisol concentrations at primary school age. METHODS: For 137 children, prenatal alcohol exposure was operationalized by the meconium biomarker EtG and by maternal self-reports during pregnancy. Two EtG cut-offs (EtG ≥10 ng/g and EtG ≥112 ng/g) were applied. Cortisol concentrations were measured in saliva and hair samples. RESULTS: Children with EtG ≥10 ng/g showed significantly reduced hair cortisol concentrations (HCCs) (p = .050, ηp2 = 0.042). For children with EtG ≥112 ng/g, the cortisol awakening response (CAR) was significantly decreased (p = .025, ηp2 = 0.070). These effects were also present in correlational analyses with continuous EtG data, speaking for partly dose-dependent effects. Especially, within the EtG ≥112 ng/g group, the basal (CAR: rp = -.642, p = .120) and cumulative (HCC: rp = -.660, p = .107) cortisol parameters were associated with child emotional symptoms at medium effect size. CONCLUSIONS: The present study showed both the biological association of intrauterine alcohol exposure with the cortisol stress system, partly dose-dependent, and the functional association with emotional and behavioral symptoms.
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Consumo de Bebidas Alcoólicas , Efeitos Tardios da Exposição Pré-Natal , Biomarcadores/metabolismo , Pré-Escolar , Etanol , Feminino , Cabelo/química , Humanos , Recém-Nascido , Mecônio , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismoRESUMO
Phase-contrast transmission electron microscopy (TEM) is a powerful tool for imaging the local atomic structure of materials. TEM has been used heavily in studies of defect structures of two-dimensional materials such as monolayer graphene due to its high dose efficiency. However, phase-contrast imaging can produce complex nonlinear contrast, even for weakly scattering samples. It is, therefore, difficult to develop fully automated analysis routines for phase-contrast TEM studies using conventional image processing tools. For automated analysis of large sample regions of graphene, one of the key problems is segmentation between the structure of interest and unwanted structures such as surface contaminant layers. In this study, we compare the performance of a conventional Bragg filtering method with a deep learning routine based on the U-Net architecture. We show that the deep learning method is more general, simpler to apply in practice, and produces more accurate and robust results than the conventional algorithm. We provide easily adaptable source code for all results in this paper and discuss potential applications for deep learning in fully automated TEM image analysis.
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Liquid-phase transmission electron microscopy is a technique for simultaneous imaging of the structure and dynamics of specimens in a liquid environment. The conventional sample geometry consists of a liquid layer tightly sandwiched between two Si3N4 windows with a nominal spacing on the order of 0.5 µm. We describe a variation of the conventional approach, wherein the Si3N4 windows are separated by a 10-µm-thick spacer, thus providing room for gas flow inside the liquid specimen enclosure. Adjusting the pressure and flow speed of humid air inside this environmental liquid cell (ELC) creates a stable liquid layer of controllable thickness on the bottom window, thus facilitating high-resolution observations of low mass-thickness contrast objects at low electron doses. We demonstrate controllable liquid thicknesses in the range 160 ± 34 to 340 ± 71 nm resulting in corresponding edge resolutions of 0.8 ± 0.06 to 1.7 ± 0.8 nm as measured for immersed gold nanoparticles. Liquid layer thickness 40 ± 8 nm allowed imaging of low-contrast polystyrene particles. Hydration effects in the ELC have been studied using poly-N-isopropylacrylamide nanogels with a silica core. Therefore, ELC can be a suitable tool for in situ investigations of liquid specimens.
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Sleep behavior and problems in children and adolescents of a psychiatric day clinic sample: results and requirements for systematic diagnostic Abstract. Sleep disorders are common in adults as well as children and adolescents. Children and adolescents in psychiatric treatment (CAP) are especially affected by sleep problems. Cognitive behavioral therapy represents the first-line treatment, preceded by a standardized procedure for sleep diagnostics. To date, no study has investigated sleep behavior in CAP day clinics in Germany. In this study, N = 46 children/adolescents receiving CAP treatment in a day clinic completed a sleep diary (7 days) and a sleep anamnesis scheme with the help of their parents, and their sleep behavior was assessed by a clinician. Furthermore, a parent- and a self-report questionnaire plus a clinical assessment of the mental disorders in the children/adolescents were collected. 52 % of the children/ adolescents exhibited sleep disorders or sleep abnormalities (= sleep disorder symptoms in the context of comorbid disorders), in particular problems falling asleep or to falling asleep and sleeping through the night (26 %). In addition, 33 % reported having nightmares. Their sleep behavior correlated significantly with their external behavior problems (r = .38 .61, p = .02-.04); their sex (female: p = .01-≤ .001, |d| = 1.57-2.50) and their age (older: p = .05, |d| = .78) also significantly influenced sleep behavior. Particularly external behavior problems were associated with sleep problems in this day-care population. In summary, a multi-method-multi-informant procedure should be established for the systematic diagnostics of sleep abnormalities, together with individualized cognitive-behavioral therapy of sleep problems, especially in patients with external behavior problems.