RÉSUMÉ
Although the overall survival rate of B cell acute lymphoblastic leukemia (B-ALL) in childhood is more than 80%, it is merely 30% in refractory/relapsed and adult patients with B-ALL. This demonstrates a need for improved therapy targeting this subgroup of B-ALL. Here, we show that the ten-eleven translocation 1 (TET1) protein, a dioxygenase involved in DNA demethylation, is overexpressed and plays a crucial oncogenic role independent of its catalytic activity in B-ALL. Consistent with its oncogenic role in B-ALL, overexpression of TET1 alone in normal precursor B cells is sufficient to transform the cells and cause B-ALL in mice within 3 to 4 months. We found that TET1 protein is stabilized and overexpressed because of its phosphorylation mediated by protein kinase C epsilon (PRKCE) and ATM serine/threonine kinase (ATM), which are also overexpressed in B-ALL. Mechanistically, TET1 recruits STAT5B to the promoters of CD72 and JCHAIN and promotes their transcription, which in turn promotes B-ALL development. Destabilization of TET1 protein by treatment with PKC or ATM inhibitors (staurosporine or AZD0156; both tested in clinical trials), or by pharmacological targeting of STAT5B, greatly decreases B-ALL cell viability and inhibits B-ALL progression in vitro and in vivo. The combination of AZD0156 with staurosporine or vincristine exhibits a synergistic effect on inhibition of refractory/relapsed B-ALL cell survival and leukemia progression in PDX models. Collectively, our study reveals an oncogenic role of the phosphorylated TET1 protein in B-ALL independent of its catalytic activity and highlights the therapeutic potential of targeting TET1 signaling for the treatment of refractory/relapsed B-ALL.
Sujet(s)
Leucémie-lymphome lymphoblastique à précurseurs B et T , Protéines proto-oncogènes , Animaux , Souris , Protéines proto-oncogènes/métabolisme , Phosphorylation , Staurosporine , Transduction du signal , Leucémie-lymphome lymphoblastique à précurseurs B et T/traitement médicamenteux , Protéines de liaison à l'ADN/métabolismeRÉSUMÉ
N6-Methyladenosine (m6A) modification and its modulators play critical roles and show promise as therapeutic targets in human cancers, including acute myeloid leukemia (AML). IGF2BP2 was recently reported as an m6A binding protein that enhances mRNA stability and translation. However, its function in AML remains largely elusive. Here we report the oncogenic role and the therapeutic targeting of IGF2BP2 in AML. High expression of IGF2BP2 is observed in AML and associates with unfavorable prognosis. IGF2BP2 promotes AML development and self-renewal of leukemia stem/initiation cells by regulating expression of critical targets (e.g., MYC, GPT2, and SLC1A5) in the glutamine metabolism pathways in an m6A-dependent manner. Inhibiting IGF2BP2 with our recently identified small-molecule compound (CWI1-2) shows promising anti-leukemia effects in vitro and in vivo. Collectively, our results reveal a role of IGF2BP2 and m6A modification in amino acid metabolism and highlight the potential of targeting IGF2BP2 as a promising therapeutic strategy in AML.
Sujet(s)
Glutamine , Leucémie aigüe myéloïde , Humains , Glutamine/métabolisme , Leucémie aigüe myéloïde/traitement médicamenteux , Leucémie aigüe myéloïde/génétique , Leucémie aigüe myéloïde/métabolisme , Stabilité de l'ARN , Pronostic , Antigènes mineurs d'histocompatibilité , Système ASC de transport d'acides aminés/génétique , Système ASC de transport d'acides aminés/métabolisme , Protéines de liaison à l'ARN/génétique , Protéines de liaison à l'ARN/métabolismeRÉSUMÉ
RNA N6 -methyladenosine (m6A) modification and its regulators fine tune gene expression and contribute to tumorigenesis. This study aims to uncover the essential role and the underlying molecular mechanism(s) of the m6A reader YTHDC1 in promoting triple negative breast cancer (TNBC) metastasis. METHODS: In vitro and in vivo models were employed to determine the pathological function of YTHDC1 in TNBC metastasis. To identify bona fide YTHDC1 target RNAs, we conducted RNA-seq, m6A-seq, and RIP-seq, followed by integrative data analysis and validation assays. RESULTS: By analyzing The Cancer Genome Atlas (TCGA) dataset, we found that elevated expression of YTHDC1 is positively correlated with poor prognosis in breast cancer patients. Using a mammary fat pad mouse model of TNBC, YTHDC1 significantly promoted lung metastasis of TNBC cells. Through multiple transcriptome-wide sequencing and integrative data analysis, we revealed dysregulation of metastasis-related pathways following YTHDC1 depletion and identified SMAD3 as a bona fide YTHDC1 target RNA. Depletion of YTHDC1 caused nuclear retention of SMAD3 mRNA, leading to lower SMAD3 protein levels. Loss of YTHDC1 led to impaired TGF-ß-induced gene expression, leading to inhibition of epithelial-mesenchymal transition (EMT) and suppressed TNBC cell migration and invasion. SMAD3 overexpression was able to restore the response to TGF-ß in YTHDC1 depleted TNBC cells. Furthermore, we demonstrated that the oncogenic role of YTHDC1 is mediated through its recognition of m6A as m6A-binding defective mutants of YTHDC1 were unable to rescue the impaired cell migration and invasion of YTHDC1 knockout TNBC cells. CONCLUSIONS: We show that YTHDC1 plays a critical oncogenic role in TNBC metastasis through promoting the nuclear export and expression of SMAD3 to augment the TGF-ß signaling cascade. Overall, our study demonstrates that YTHDC1 is vital for TNBC progression by enhancing TNBC cell survival and TGF-ß-mediated EMT via SMAD3 to enable the formation of distant metastasis and highlights the therapeutic potential of targeting the YTHDC1/m6A/SMAD3 axis for TNBC treatment.
Sujet(s)
Tumeurs du sein triple-négatives , Animaux , Mouvement cellulaire/génétique , Transition épithélio-mésenchymateuse/génétique , Humains , Souris , Protéines de tissu nerveux/métabolisme , ARN , Facteurs d'épissage des ARN/génétique , Facteurs d'épissage des ARN/métabolisme , Facteur de croissance transformant bêta/métabolisme , Tumeurs du sein triple-négatives/anatomopathologieRÉSUMÉ
METTL16 has recently been identified as an RNA methyltransferase responsible for the deposition of N6-methyladenosine (m6A) in a few transcripts. Whether METTL16 methylates a large set of transcripts, similar to METTL3 and METTL14, remains unclear. Here we show that METTL16 exerts both methyltransferase activity-dependent and -independent functions in gene regulation. In the cell nucleus, METTL16 functions as an m6A writer to deposit m6A into hundreds of its specific messenger RNA targets. In the cytosol, METTL16 promotes translation in an m6A-independent manner. More specifically, METTL16 directly interacts with the eukaryotic initiation factors 3a and -b as well as ribosomal RNA through its Mtase domain, thereby facilitating the assembly of the translation-initiation complex and promoting the translation of over 4,000 mRNA transcripts. Moreover, we demonstrate that METTL16 is critical for the tumorigenesis of hepatocellular carcinoma. Collectively, our studies reveal previously unappreciated dual functions of METTL16 as an m6A writer and a translation-initiation facilitator, which together contribute to its essential function in tumorigenesis.
Sujet(s)
Adénosine/analogues et dérivés , Carcinogenèse/métabolisme , Carcinome hépatocellulaire/enzymologie , Tumeurs du foie/enzymologie , Methyltransferases/métabolisme , Biosynthèse des protéines , Maturation post-transcriptionnelle des ARN , ARN messager/métabolisme , Adénosine/métabolisme , Animaux , Carcinogenèse/génétique , Carcinogenèse/anatomopathologie , Carcinome hépatocellulaire/génétique , Carcinome hépatocellulaire/anatomopathologie , Cytosol/enzymologie , Facteur-3 d'initiation eucaryote/génétique , Facteur-3 d'initiation eucaryote/métabolisme , Régulation de l'expression des gènes tumoraux , Cellules HEK293 , Cellules HepG2 , Humains , Tumeurs du foie/génétique , Tumeurs du foie/anatomopathologie , Methyltransferases/génétique , Souris de lignée NOD , Souris SCID , ARN messager/génétique , ARN ribosomique/génétique , ARN ribosomique/métabolisme , Transduction du signal , Charge tumoraleRÉSUMÉ
Infant attachment is a key predictor of later socioemotional functioning, but it is not clear how parental responsivity to infant expressive behavior is associated with attachment outcomes. A mid-range model of responsivity holds that both unresponsive and highly reactive parental behaviors lead to insecure and disorganized attachment. We examined the relationship between maternal (and infant) contingent responsivity and attachment in a high-risk sample. Participants were 625 infant-mother pairs from a longitudinal study of children with and without prenatal drug exposure and variable levels of associated social risks. Infant-mother pairs participated in the Face-to-Face/Still-Face paradigm (FFSF) at 4-months and in the Strange Situation Procedure (SSP) at 18-months. A model incorporating both linear and quadratic responsivity effects indicated that mothers who were either very high (reactive) or very low (unresponsive) in responsivity were more likely to have infants with disorganized attachment outcomes. While maternal responsivity was associated with attachment disorganization, no associations between maternal responsivity, and attachment security/insecurity were detected. Infant responsivity to mother was not associated with attachment outcomes. The findings suggest the importance of mid-range levels of maternal responsivity in the development of organized attachment among infants facing high levels of prenatal and social risk.
Sujet(s)
Comportement du nouveau-né et du nourrisson , Attachement à l'objet , Enfant , Femelle , Humains , Nourrisson , Comportement du nouveau-né et du nourrisson/psychologie , Études longitudinales , Comportement maternel/psychologie , GrossesseRÉSUMÉ
Four programmed death ligand 1 (PD-L1) immunohistochemistry assays (28-8, 22C3, SP263, and SP142) have been approved for use by the US Food and Drug Administration (FDA). Analytical concordance between these assays has been evaluated in multiple studies. This systematic review included studies that investigated the analytical concordance of immunohistochemistry assays utilizing two or more PD-L1 antibodies from FDA-approved diagnostics for evaluation of PD-L1 expression on tumor or immune cells across a range of tumor types and algorithms. METHODS: Literature searches were conducted in MEDLINE (via PubMed) and EMBASE to identify studies published between January 1, 2010, and March 31, 2019, that evaluated analytical concordance between two or more assays based on antibodies from FDA-approved assays. Proceedings of key oncology and pathology congresses that took place between January 2016 and March 2019 were searched for abstracts of studies evaluating PD-L1 assay concordance. RESULTS: A total of 42 studies across a range of tumor types met the selection criteria. Concordance between 28-8-, 22C3-, and SP263-based assays in lung cancer, urothelial carcinoma, and squamous cell carcinoma of the head and neck was high when used to assess PD-L1 expression on tumor cells (TCs). SP142-based assays had overall low concordance with other approved assays when used to assess PD-L1 expression on TCs. Analytical concordance for assessment of PD-L1 expression on immune cells was variable and generally lower than for PD-L1 expression on TCs. CONCLUSION: A large body of evidence supports the potential interchangeability of 28-8-, 22C3-, and SP263-based assays for the assessment of PD-L1 expression on TCs in lung cancer. Further studies are required in tumor types for which less evidence is available.
Sujet(s)
Anticorps/analyse , Antigène CD274/immunologie , Tumeurs/diagnostic , Tumeurs/immunologie , Humains , Immunohistochimie , Stadification tumorale , États-Unis , Food and Drug Administration (USA)RÉSUMÉ
Infant attachment is a critical indicator of healthy infant social-emotional functioning, which is typically measured using the gold-standard Strange Situation Procedure (SSP). However, expert-based attachment classifications from the SSP are time-intensive (with respect both to expert training and rating), and do not provide an objective, continuous record of infant behavior. To continuously quantify predictors of key attachment behaviors and dimensions, multimodal movement and audio data were collected during the SSP. Forty-nine 1-year-olds and their mothers participated in the SSP and were tracked in three-dimensional space using five synchronized Kinect sensors; LENA recordings were used to quantify crying duration. Theoretically-informed multimodal measures of attachment-related behavior (e.g., dyadic contact duration, infant velocity of approach toward the mother, and infant crying) were used to predict expert rating scales and dimensional summaries of attachment outcomes. Stepwise regressions identified sets of multimodal objective measures that were significant predictors of eight of nine of the expert ratings of infant attachment behaviors in the SSP's two reunions. These multimodal measures predicted approximately half of the variance in the summary approach/avoidance and resistance/disorganization attachment dimensions. Incorporating all objective measures as predictors regardless of significance levels, predicted individual ratings within an average of one point on the original Likert scales. The results indicate that relatively inexpensive Kinect and LENA sensors can be harnessed to quantify attachment behavior in a key assessment protocol, suggesting the promise of objective measurement to understanding infant-parent interaction.
Sujet(s)
Relations mère-enfant , Attachement à l'objet , Émotions , Femelle , Humains , Nourrisson , Comportement du nouveau-né et du nourrisson , MèresRÉSUMÉ
R-2-hydroxyglutarate (R-2HG), a metabolite produced by mutant isocitrate dehydrogenases (IDHs), was recently reported to exhibit anti-tumor activity. However, its effect on cancer metabolism remains largely elusive. Here we show that R-2HG effectively attenuates aerobic glycolysis, a hallmark of cancer metabolism, in (R-2HG-sensitive) leukemia cells. Mechanistically, R-2HG abrogates fat-mass- and obesity-associated protein (FTO)/N6-methyladenosine (m6A)/YTH N6-methyladenosine RNA binding protein 2 (YTHDF2)-mediated post-transcriptional upregulation of phosphofructokinase platelet (PFKP) and lactate dehydrogenase B (LDHB) (two critical glycolytic genes) expression and thereby suppresses aerobic glycolysis. Knockdown of FTO, PFKP, or LDHB recapitulates R-2HG-induced glycolytic inhibition in (R-2HG-sensitive) leukemia cells, but not in normal CD34+ hematopoietic stem/progenitor cells, and inhibits leukemogenesis in vivo; conversely, their overexpression reverses R-2HG-induced effects. R-2HG also suppresses glycolysis and downregulates FTO/PFKP/LDHB expression in human primary IDH-wild-type acute myeloid leukemia (AML) cells, demonstrating the clinical relevance. Collectively, our study reveals previously unrecognized effects of R-2HG and RNA modification on aerobic glycolysis in leukemia, highlighting the therapeutic potential of targeting cancer epitranscriptomics and metabolism.
Sujet(s)
Alpha-ketoglutarate-dependent dioxygenase FTO/génétique , Antinéoplasiques/pharmacologie , Glutarates/pharmacologie , Glycolyse/génétique , Lactate dehydrogenases/génétique , Leucémie aigüe myéloïde/traitement médicamenteux , Phosphofructokinase-1, type C/génétique , Alpha-ketoglutarate-dependent dioxygenase FTO/antagonistes et inhibiteurs , Alpha-ketoglutarate-dependent dioxygenase FTO/métabolisme , Animaux , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Femelle , Fluorouracil/pharmacologie , Régulation de l'expression des gènes tumoraux , Glycolyse/effets des médicaments et des substances chimiques , Cellules HEK293 , Humains , Cellules K562 , Lactate dehydrogenases/antagonistes et inhibiteurs , Lactate dehydrogenases/métabolisme , Leucémie aigüe myéloïde/génétique , Leucémie aigüe myéloïde/mortalité , Leucémie aigüe myéloïde/anatomopathologie , Mâle , Souris , Souris de lignée C57BL , Souris transgéniques , Phosphorylation oxydative/effets des médicaments et des substances chimiques , Phosphofructokinase-1, type C/antagonistes et inhibiteurs , Phosphofructokinase-1, type C/métabolisme , Petit ARN interférent/génétique , Petit ARN interférent/métabolisme , Protéines de liaison à l'ARN/génétique , Protéines de liaison à l'ARN/métabolisme , Transduction du signal , Analyse de survie , Tests d'activité antitumorale sur modèle de xénogreffeRÉSUMÉ
Fat mass and obesity-associated protein (FTO), an RNA N6-methyladenosine (m6A) demethylase, plays oncogenic roles in various cancers, presenting an opportunity for the development of effective targeted therapeutics. Here, we report two potent small-molecule FTO inhibitors that exhibit strong anti-tumor effects in multiple types of cancers. We show that genetic depletion and pharmacological inhibition of FTO dramatically attenuate leukemia stem/initiating cell self-renewal and reprogram immune response by suppressing expression of immune checkpoint genes, especially LILRB4. FTO inhibition sensitizes leukemia cells to T cell cytotoxicity and overcomes hypomethylating agent-induced immune evasion. Our study demonstrates that FTO plays critical roles in cancer stem cell self-renewal and immune evasion and highlights the broad potential of targeting FTO for cancer therapy.
Sujet(s)
Alpha-ketoglutarate-dependent dioxygenase FTO/antagonistes et inhibiteurs , Auto-renouvellement cellulaire/effets des médicaments et des substances chimiques , Antienzymes/pharmacologie , Échappement immunitaire/effets des médicaments et des substances chimiques , Alpha-ketoglutarate-dependent dioxygenase FTO/composition chimique , Alpha-ketoglutarate-dependent dioxygenase FTO/métabolisme , Anthracènes/composition chimique , Anthracènes/pharmacologie , Dérivés du biphényle/composition chimique , Dérivés du biphényle/pharmacologie , Lignée cellulaire tumorale , Survie cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/génétique , Antienzymes/composition chimique , Antienzymes/métabolisme , Régulation de l'expression des gènes tumoraux/effets des médicaments et des substances chimiques , Humains , Échappement immunitaire/génétique , Leucémies/génétique , Leucémies/anatomopathologie , Leucémies/prévention et contrôle , Glycoprotéines membranaires/génétique , Glycoprotéines membranaires/métabolisme , Structure moléculaire , Liaison aux protéines/effets des médicaments et des substances chimiques , Domaines protéiques , Récepteurs immunologiques/génétique , Récepteurs immunologiques/métabolisme , Cellules U937RÉSUMÉ
AIMS: Programmed death-1/programmed death ligand 1 (PD-1/PD-L1) inhibitor therapy is accompanied by companion or complementary PD-L1 testing in some tumour types. We investigated utilisation of the Dako PD-L1 IHC 28-8 and 22C3 pharmDx assays and the Ventana PD-L1 (SP142) assay and evaluated concordance between the 28-8 and 22C3 assays in a real-world cohort of patients tested at a single US national reference laboratory. METHODS: NeoGenomics Laboratories performed PD-L1 testing on tumour samples between October 2015 and March 2018. PD-L1 test results were matched with patient characteristics using unique identifiers. Concordance between the 28-8 and 22C3 assays was evaluated in matched tumour samples. Data were evaluated across multiple tumour types and in subgroups of patients with lung cancer, melanoma, squamous cell carcinoma of the head and neck, and urothelial carcinoma. RESULTS: 62 180 individual PD-L1 tests were conducted on samples from 55 652 patients. PD-L1 test volume increased ~10-fold over the period evaluated. Test failure rates were typically low, and test turnaround time (TAT) ranged between 2 and 4 days. Concordance between the 28-8 and 22C3 assays was strong in the overall population and across tumour type subgroups (Kendall's tau correlations of 0.94 and 0.92-0.98, respectively). CONCLUSIONS: Test failure rates for PD-L1 tests were low and TAT remained reasonable despite marked increases in test volume. Concordance was high between the 28-8 and 22C3 assays across a range of tumour types and biopsy locations. These findings add to the literature showing high concordance between the 28-8 and 22C3 assays.
Sujet(s)
Antigène CD274/analyse , Marqueurs biologiques tumoraux/analyse , Immunohistochimie , Humains , Immunohistochimie/méthodes , Immunohistochimie/normes , Immunohistochimie/statistiques et données numériques , Tumeurs/métabolisme , Reproductibilité des résultatsRÉSUMÉ
N6-methyladenosine (m6A), the most abundant internal modification in mRNA, has been implicated in tumorigenesis. As an m6A demethylase, ALKBH5 has been shown to promote the development of breast cancer and brain tumors. However, in acute myeloid leukemia (AML), ALKBH5 was reported to be frequently deleted, implying a tumor-suppressor role. Here, we show that ALKBH5 deletion is rare in human AML; instead, ALKBH5 is aberrantly overexpressed in AML. Moreover, its increased expression correlates with poor prognosis in AML patients. We demonstrate that ALKBH5 is required for the development and maintenance of AML and self-renewal of leukemia stem/initiating cells (LSCs/LICs) but not essential for normal hematopoiesis. Mechanistically, ALKBH5 exerts tumor-promoting effects in AML by post-transcriptional regulation of its critical targets such as TACC3, a prognosis-associated oncogene in various cancers. Collectively, our findings reveal crucial functions of ALKBH5 in leukemogenesis and LSC/LIC self-renewal/maintenance and highlight the therapeutic potential of targeting the ALKBH5/m6A axis.
Sujet(s)
Auto-renouvellement cellulaire , Leucémie aigüe myéloïde , AlkB Homolog 5, RNA demethylase/génétique , Carcinogenèse/génétique , Humains , Leucémie aigüe myéloïde/génétique , Protéines associées aux microtubules , Cellules souches tumoralesRÉSUMÉ
Although difficulties with social relationships are key to autism spectrum disorder (ASD), no previous study has examined infant attachment security prior to ASD diagnosis. We prospectively assessed attachment security at 15 months in high-risk infants with later ASD (high-risk/ASD, n = 16), high-risk infants without later ASD (high-risk/no-ASD, n = 40), and low-risk infants without later ASD (low-risk/no-ASD, n = 39) using the Strange Situation Procedure. High-risk/ASD infants were disproportionately more likely to be classified as insecure (versus secure) and more likely to be classified as insecure-resistant (versus secure or avoidant) than high-risk/no-ASD and low-risk/no-ASD infants. High-risk infants with insecure-resistant attachments were over nine times more likely to receive an ASD diagnosis than high-risk infants with secure attachments. Insecure-resistant attachment in high-risk infants suggests a propensity toward negative affect with the parent in conditions of stress. Insecure-resistant attachment may prove useful as a potential early index of propensity toward ASD diagnosis in high-risk siblings, while insecure-resistant attachment in the context of emergent autism may contribute to difficulties experienced by children with ASD and their families.
Sujet(s)
Trouble du spectre autistique/psychologie , Attachement à l'objet , Femelle , Humains , Nourrisson , Mâle , Parents , Études prospectives , Facteurs de risque , Fratrie , Comportement socialRÉSUMÉ
Human observations can only capture a portion of ongoing classroom social activity, and are not ideal for understanding how children's interactions are spatially structured. Here we demonstrate how social interaction can be investigated by modeling automated continuous measurements of children's location and movement using a commercial system based on radio frequency identification. Continuous location data were obtained from 16 five-year-olds observed during three 1-h classroom free play observations. Illustrative coordinate mapping indicated that boys and girls tended to cluster in different physical locations in the classroom, but there was no suggestion of gender differences in children's velocity (i.e., speed of movement). To detect social interaction, we present the radial distribution function, an index of when children were in social contact at greater than chance levels. Rank-order plots indicated that children were in social contact tens to hundreds of times more with some peers than others. We illustrate the use of social ties (higher than average levels of social contact) to visualize the classroom network. Analysis of the network suggests that transitivity is a potential lens through which to examine male, female, and mixed-sex cliques. The illustrative findings suggest the validity of the new measurement approach by re-examining well-established gender segregation findings from a new perspective.
RÉSUMÉ
OBJECTIVE: There is a prevailing notion that children with autism spectrum disorder (ASD) exhibit intense negative and attenuated positive emotions, although the empirical evidence regarding their emotional expressiveness (EE) is limited. Given the importance of emotions in shaping social and cognitive development, we examined intensity and valence of EE and links between EE and autism severity and parent-reported temperament in ASD. METHOD: Toddlers (aged 21.2 months) with ASD (n = 43), developmental delay (DD, n = 16), and typical development (TD, n = 40) underwent standardized probes designed to induce anger, joy, and fear. Intensity of EE through facial and vocal channels were coded offline. Autism severity and temperament were quantified using the Autism Diagnostic Observation Schedule-2 (ADOS-2) and Early Childhood Behavior Questionnaire (ECBQ). RESULTS: The ASD group exhibited less intense fear compared to both the DD and TD groups, more intense anger than DD but not TD, with no differences in joy intensity. All groups showed similar levels of incongruous negative EE. Intensity of fear and anger were not associated with severity of autism symptoms, but lower intensity of joy was related to greater autism severity. Expressed fear and joy were associated with temperament. CONCLUSION: The study provides no support for a negative emotionality bias in ASD. Instead, toddlers with ASD display a muted response to threat and an accentuated response to goal blockage, whereas the ability to express positive emotions appears intact. Negative emotionality and social disability dimensions are independent. The study demonstrates the complexity of EE in ASD and motivates investigations into underlying mechanisms as well as its role in shaping complex phenotypes of affected children.
Sujet(s)
Trouble du spectre autistique/physiopathologie , Incapacités de développement/physiopathologie , Émotions/physiologie , Tempérament/physiologie , Comportement de l'enfant , Enfant d'âge préscolaire , Femelle , Humains , Nourrisson , MâleRÉSUMÉ
Children from low SES backgrounds hear, on average, fewer words at home than those from high SES backgrounds. This word gap is associated with widening achievement differences in children's language abilities and school readiness. However relatively little is known about adult and child speech in childcare settings, in which approximately 30% of American children are enrolled. We examined the influence of teacher and peer language input on children's in-class language use and language development in an intervention classroom for low-SES, high-risk 2- to 3-year-olds. Over the course of a year, day-long recordings of the classroom were collected weekly with LENA recorders. Using LENA software algorithms, we found that language input from peers was positively related to children's in-class language use, both in-the-moment and over the course of each day, as were the number of conversational turns in which children and teachers engaged Both peer input and conversational turns with teachers were also positively related to children's language development rates, as indexed by increases in vocabulary size. Together these results indicate the importance of child-specific rates of classroom language input in the language development of high-risk, preschoolers.
Sujet(s)
Langage de l'enfant , Communication , Développement du langage oral , Environnement social , Facteurs socioéconomiques , Enfant d'âge préscolaire , Femelle , Humains , Mâle , Établissements scolaires , VocabulaireRÉSUMÉ
A growing number of social scientists have turned to differential equations as a tool for capturing the dynamic interdependence among a system of variables. Current tools for fitting differential equation models do not provide a straightforward mechanism for diagnosing evidence for qualitative shifts in dynamics, nor do they provide ways of identifying the timing and possible determinants of such shifts. In this paper, we discuss regime-switching differential equation models, a novel modeling framework for representing abrupt changes in a system of differential equation models. Estimation was performed by combining the Kim filter (Kim and Nelson State-space models with regime switching: classical and Gibbs-sampling approaches with applications, MIT Press, Cambridge, 1999) and a numerical differential equation solver that can handle both ordinary and stochastic differential equations. The proposed approach was motivated by the need to represent discrete shifts in the movement dynamics of [Formula: see text] mother-infant dyads during the Strange Situation Procedure (SSP), a behavioral assessment where the infant is separated from and reunited with the mother twice. We illustrate the utility of a novel regime-switching differential equation model in representing children's tendency to exhibit shifts between the goal of staying close to their mothers and intermittent interest in moving away from their mothers to explore the room during the SSP. Results from empirical model fitting were supplemented with a Monte Carlo simulation study to evaluate the use of information criterion measures to diagnose sudden shifts in dynamics.
Sujet(s)
Psychométrie/méthodes , Simulation numérique , Femelle , Mouvements de la tête , Humains , Nourrisson , Comportement du nouveau-né et du nourrisson , Méthode de Monte Carlo , Relations mère-enfant/psychologie , Sciences sociales/méthodes , Logiciel , Processus stochastiquesRÉSUMÉ
Brain-behavior associations in fMRI studies are typically restricted to a single level of analysis: either a circumscribed brain region-of-interest (ROI) or a larger network of brain regions. However, this common practice may not always account for the interdependencies among ROIs of the same network or potentially unique information at the ROI-level, respectively. To account for both sources of information, we combined measurement and structural components of structural equation modeling (SEM) approaches to empirically derive networks from ROI activity, and to assess the association of both individual ROIs and their respective whole-brain activation networks with task performance using three large task-fMRI datasets and two separate brain parcellation schemes. The results for working memory and relational tasks revealed that well-known ROI-performance associations are either non-significant or reversed when accounting for the ROI's common association with its corresponding network, and that the network as a whole is instead robustly associated with task performance. The results for the arithmetic task revealed that in certain cases, an ROI can be robustly associated with task performance, even when accounting for its associated network. The SEM framework described in this study provides researchers additional flexibility in testing brain-behavior relationships, as well as a principled way to combine ROI- and network-levels of analysis.
Sujet(s)
Cartographie cérébrale/méthodes , Encéphale/physiologie , Modèles neurologiques , Réseau nerveux/physiologie , Adulte , Femelle , Humains , Traitement d'image par ordinateur/méthodes , Imagerie par résonance magnétique , Mâle , Analyse et exécution des tâches , Jeune adulteRÉSUMÉ
According to dominant theories of affect, humans innately and universally express a set of emotions using specific configurations of prototypical facial activity. Accordingly, thousands of studies have tested emotion recognition using sets of highly intense and stereotypical facial expressions, yet their incidence in real life is virtually unknown. In fact, a commonplace experience is that emotions are expressed in subtle and nonprototypical forms. Such facial expressions are at the focus of the current study. In Experiment 1, we present the development and validation of a novel stimulus set consisting of dynamic and subtle emotional facial displays conveyed without constraining expressers to using prototypical configurations. Although these subtle expressions were more challenging to recognize than prototypical dynamic expressions, they were still well recognized by human raters, and perhaps most importantly, they were rated as more ecological and naturalistic than the prototypical expressions. In Experiment 2, we examined the characteristics of subtle versus prototypical expressions by subjecting them to a software classifier, which used prototypical basic emotion criteria. Although the software was highly successful at classifying prototypical expressions, it performed very poorly at classifying the subtle expressions. Further validation was obtained from human expert face coders: Subtle stimuli did not contain many of the key facial movements present in prototypical expressions. Together, these findings suggest that emotions may be successfully conveyed to human viewers using subtle nonprototypical expressions. Although classic prototypical facial expressions are well recognized, they appear less naturalistic and may not capture the richness of everyday emotional communication. (PsycINFO Database Record