Sensitive Periods Of Development Research Articles

ПОДОЛАННЯ ГЕНДЕРНИХ СТЕРЕОТИПІВ НА УРОКАХ ФІЗИЧНОЇ КУЛЬТУРИ ЗАСОБАМИ СПОРТИВНИХ ІГОР

The article analyzes the manifestations of gender stereotypes in sports and notes that despite some positive changes in pedagogy, in particular, when it comes to physical education, there is still a unilateral approach in sex-role education of children. Even in new pedagogical publications, the difference between sexes is often reduced only to the physiological differences. It is stated that the introduction of sports games, in particular basketball, at high school allows to overcome a number of gender stereotypes. The model experiment has determined the appropriate age of starting playing basketball, on the basis of which you can see that at high school, both boys and girls show equally high achievements in this sport. This pattern allows you to train the basic skills of the game and directly two-way play in mixed teams. As a result, students develop an understanding that success, effectiveness and victory depend on perseverance, diligence, work on themselves and their own skills, not on gender. It is emphasized that the purpose of studying sport games at high school, in particular basketball, is not training professional athletes, but education of a number of useful life skills: the ability to work in a team, ingenuity, agility, initiative, leadership qualities and, importantly, overcome gender stereotypes about the benefits of a certain sex in sports. Thus, generalization of the results of the model experiment and many years of practical experience make it possible to argue that basketball is an effective way to overcome gender stereotypes in physical education lessons at high school. Key words: gender stereotypes, sports games, basketball, model experiment, sensitive periods of development, mixed teams.

0104 Acoustic enhancement of slow-wave sleep in healthy adolescents

Abstract Introduction Adolescents have a stable sleep-need of between 9-10 hours a night, yet a pattern of markedly restricted sleep duration, particularly on school nights, has given rise to an epidemic of sleep deprivation in this population. As demonstrated by large numbers of studies, insufficient, irregular, and/or poor-quality sleep is a risk factor for both mental health problems and learning difficulties. Enhancing slow-wave sleep through non-pharmacological means may be a mechanism for alleviating daytime functional deficits in youth. In this study, we tested the feasibility of enhancing slow-wave sleep in healthy adolescents using a closed-loop, sleep-wearable device (SmartSleep, Phillips-Respironics) which monitors the EEG signal to automatically detect sleep stages, slow-waves, and micro-arousals to deliver acoustic stimulation to enhance SWA. Methods Seventeen healthy adolescents (15.5±1.8 years; 11 female) who endorsed sleep restriction and symptoms of daytime sleepiness participated in a randomized, cross-over study. Participation included wearing SmartSleep for two consecutive 4-night periods at home—one period with acoustic stimulation (STIM) and one without (SHAM). During STIM, SmartSleep monitors the EEG in real-time and delivers acoustic tones (50 ms, 1 second interval between) through embedded headphones at an intensity dynamically modulated by sleep depth. Stimulation is stopped when an arousal or sleep stage-shift is detected. During SHAM recording, the same stimulation protocol is applied with tones played at zero volume. Results No differences were observed in any measure of sleep architecture. A mixed effects linear regression model was used to analyze the impact of condition (STIM vs SHAM) on both cumulative and average SWA during N2N3 and N3 sleep. At the group level, cumulative SWA during N2N3 and average SWA during N3 were significantly increased in STIM relative to SHAM (p=0.01; p=0.02, respectively), while age (p=0.67) and sex (p=0.71) had no effect. Despite the significant group effects, not all youth were responders; an average increase in cumulative SWA (11.5 ± 7.1%) in the STIM condition was observed in 12/17 participants. Conclusion Consecutive nights of acoustic stimulation enhanced SWA in otherwise healthy, sleep-restricted adolescents. These data suggest that acoustic stimulation during sleep may be a viable method for optimizing slow-wave activity and minimizing the emotional and cognitive consequences of sleep restriction during this sensitive developmental period. Support (If Any)

Audiovisual spatial recalibration but not integration is shaped by early sensory experience

SummaryTo clarify the role of sensory experience during early development for adult multisensory learning capabilities, we probed audiovisual spatial processing in human individuals who had been born blind because of dense congenital cataracts (CCs) and who subsequently had received cataract removal surgery, some not before adolescence or adulthood. Their ability to integrate audio-visual input and to recalibrate multisensory spatial representations was compared to normally sighted control participants and individuals with a history of developmental (later onset) cataracts. Results in CC individuals revealed both normal multisensory integration in audiovisual trials (ventriloquism effect) and normal recalibration of unimodal auditory localization following audiovisual discrepant exposure (ventriloquism aftereffect) as observed in the control groups. In addition, only the CC group recalibrated unimodal visual localization after audiovisual exposure. Thus, in parallel to typical multisensory integration and learning, atypical crossmodal mechanisms coexisted in CC individuals, suggesting that multisensory recalibration capabilities are defined during a sensitive period in development.

P137. Differential Effects of Early Life Stress During Sensitive Periods of Development on Anxiety-Like Behavior and Gene Expression Response in Adult Mice

Preclinical ELS models (e.g., maternal separation) have been extensively used to investigate biomolecular changes underlying the behavioral outcomes in response to stress exposure during early postnatal period. However, it still unclear how the reprograming effects of these early stress experiences could interact with the exposure to a second stressor during later periods of development, such as adolescence. To address that, this study investigated how maternal separation would interact with chronic adolescence stress exposure on anxiety-like response, gene and protein expression of GR and FKBP5 in the hippocampus.

Development of a theoretically and empirically grounded emotion knowledge training for the young

Background: Digital mental health trainings can be an impactful and efficient way to promote well-being and prevent psychopathology during the sensitive developmental periods of adolescence and young adulthood. However, many online and app-based trainings are often not grounded in science or have low engagement rates due to poor usability. The aim of the current project was to tackle both of these issues in the development of an emotional competence skills training for youth (target age: 16-22). Given that deficits in emotional competence constitute a risk factor for poor mental health, we built a training that aims to increase knowledge and understanding of emotions and the processes that underlie them. Methods: As a theoretical base, we used the Component Process Model to teach youth to understand their emotional experiences as a dynamic process that involves the activation of appraisals, bodily reactions, expressions, action tendencies and subjective feelings. To avoid issues related to low engagement, we included youth across various stages throughout the development of the training program, which allowed us to make changes incrementally at each stage. Feedback from several focus groups, Youth Advisory Board meetings, and a pilot study resulted in the development of a gamified emotional knowledge skills training that teaches young people how to understand, recognize, and reflect on their emotions. Results: Results showed that when it came to digital mental health trainings, youth valued personalization, relatability, fast and colorful graphics, professional audiovisual elements, interactivity, ease-of-use, privacy protection and scientific legitimacy. Conclusions: In this paper, we describe and reflect on the process of developing the training and offer suggestions to help guide future researchers in building mental health trainings that are both supported by science and appealing to young users.

Sleep reactivity as a potential pathway from childhood abuse to adult insomnia

BackgroundSurvivors of childhood abuse are prone to adult insomnia, but the mechanisms for this development are poorly understood. Abuse that occurs during sensitive developmental periods might affect risk for insomnia by impacting emerging stress regulatory processes. Sleep reactivity refers to the sensitivity of the sleep system to stress and is a robust risk factor for insomnia. Recent evidence shows stress exposure itself worsens sleep reactivity, thereby increasing insomnia vulnerability. In this preliminary study, we hypothesized the association between childhood abuse experiences and adult insomnia would be mediated through greater sleep reactivity. MethodsCommunity adults were recruited from the United States during the COVID-19 pandemic between June 2020 and June 2021 (N = 241, 88% female, Mage = 39, SD = 13.40). Participants completed a cross-sectional survey that included the Childhood Trauma Questionnaire, Ford Insomnia Response to Stress Test, Insomnia Severity Index, and a measure of general COVID-19 stress. ResultsReporting more frequent childhood emotional, physical, or sexual abuse was associated with more severe insomnia during the COVID-19 pandemic. Only childhood emotional and physical (but not sexual) abuse histories were associated with greater sleep reactivity, which exerted an indirect effect on the relationships between these two abuse types and insomnia symptoms. These findings were robust to the effects of gender, age, and stress about the COVID-19 pandemic. ConclusionsThis preliminary study suggests recurrent emotional and physical abuse in childhood might promote later insomnia through heightened sleep reactivity. Stress management interventions could be important to prevent insomnia for abuse survivors by bolstering resilience of the sleep system.

Sex-dependent impact of microbiota status on cerebral μ-opioid receptor density in fischer rats.

μ‐opioid receptors (MOPr) play a critical role in social play, reward and pain, in a sex‐ and age‐dependent manner. There is evidence to suggest that sex and age differences in brain MOPr density may be responsible for this variability; however, little is known about the factors driving these differences in cerebral MOPr density. Emerging evidence highlights gut microbiota's critical influence and its bidirectional interaction with the brain on neurodevelopment. Therefore, we aimed to determine the impact of gut microbiota on MOPr density in male and female brains at different developmental stages. Quantitative [3H]DAMGO autoradiographic binding was carried out in the forebrain of male and female conventional (CON) and germ‐free (GF) rats at postnatal days (PND) 8, 22 and 116–150. Significant ‘microbiota status X sex’, ‘age X brain region’ interactions and microbiota status‐ and age‐dependent effects on MOPr binding were uncovered. Microbiota status influenced MOPr levels in males but not females, with higher MOPr levels observed in GF versus CON rats overall regions and age groups. In contrast, no overall sex differences were observed in GF or CON rats. Interestingly, within‐age planned comparison analysis conducted in frontal cortical and brain regions associated with reward revealed that this microbiota effect was restricted only to PND22 rats. Thus, this pilot study uncovers the critical sex‐dependent role of gut microbiota in regulating cerebral MOPr density, which is restricted to the sensitive developmental period of weaning. This may have implications in understanding the importance of microbiota during early development on opioid signalling and associated behaviours.

Impact of Adolescent Intermittent Ethanol Exposure on Social Investigation, Social Preference, and Neuronal Activation in cFos-LacZ Male and Female Rats.

Adolescence is a sensitive developmental period during which alcohol use is often initiated and consumed in high quantities, often at binge or even high-intensity drinking levels. Our lab has repeatedly found that adolescent intermittent ethanol (AIE) exposure in rats results in long-lasting social impairments, specifically in males, however our knowledge of the neuronal underpinnings to this sex-specific effect of AIE is limited. The present study was designed to test whether social anxiety-like alterations in AIE-exposed males would be accompanied by alterations of neuronal activation across brain regions associated with social behavior, with AIE females demonstrating no social impairments and alterations in neuronal activation. Adolescent male and female cFos-LacZ transgenic rats on a Sprague-Dawley background were exposed to ethanol (4 g/kg, 25% v/v) or water via intragastric gavage every other day during postnatal days (P) 25–45 for a total of 11 exposures (n = 13 per group). Social behavior of adult rats was assessed on P70 using a modified social interaction test, and neuronal activation in brain regions implicated in social responding was assessed via β-galactosidase (β-gal) expression. We found that AIE exposure in males resulted in a significantly lower social preference coefficient relative to water-exposed controls, with no effect evident in females. Exposure-specific relationships between social behavior and neuronal activation were identified, with AIE eliminating correlations found in water controls related to social interaction, and eliciting negative correlations mainly in limbic regions in a sex-specific manner. AIE exposure in the absence of social testing was also found to differentially affect neural activity in the orbitofrontal cortex and central amygdala in males and females. These data suggest that AIE produces sex-specific social impairments that are potentially driven by differential neuronal activation states in regions important for social behavior, including the medial prefrontal and orbitofrontal cortices, nucleus accumbens, lateral septum, and central amygdala. Future studies should be focused on identification of specific neuronal phenotypes activated by interaction with a social partner in AIE-exposed subjects and their control counterparts.

Structural, functional, and behavioral significance of sex and gonadal hormones in the basolateral amygdala: A review of preclinical literature.

The basolateral amygdala (BLA) is intimately involved in the development of neuropsychiatric disorders such as anxiety and alcohol use disorder (AUD). These disorders have clear sex biases, with women more likely to develop an anxiety disorder and men more likely to develop AUD. Preclinical models have largely confirmed these sex-specific vulnerabilities and emphasize the effects of sex hormones on behaviors influenced by the BLA. This review will discuss sex differences in BLA-related behaviors and highlight potential mechanisms mediated by altered BLA structure and function, including the composition of GABAergic interneuron subpopulations, glutamatergic pyramidal neuron morphology, glutamate/GABA neurotransmission, and neuromodulators. Further, sex hormones differentially organize dimorphic circuits during sensitive developmental periods (organizational effects) and initiate more transient effects throughout adulthood (activational effects). Current literature indicates that estradiol and allopregnanolone, a neuroactive progestogen, generally reduce BLA-related behaviors through a variety of mechanisms, including activation of estrogen receptors or facilitation of GABAA-mediated inhibition, respectively. This enhanced GABAergic inhibition may protect BLA pyramidal neurons from the excitability associated with anxiety and alcohol withdrawal. Understanding sex differences and the effects of sex hormones on BLA structure and function may help explain sex-specific vulnerabilities in BLA-related behaviors and ultimately improve treatments for anxiety and AUD.

Development of the Ontogenetic Self-Regulation Clock.

To date, there is no overarching proposition for the ontogenetic-neurobiological basis of self-regulation. This paper suggests that the balanced self-regulatory reaction of the fetus, newborn and infant is based on a complex mechanism starting from early brainstem development and continuing to progressive control of the cortex over the brainstem. It is suggested that this balance occurs through the synchronous reactivity between the sympathetic and parasympathetic systems, both which originate from the brainstem. The paper presents an evidence-based approach in which molecular excitation-inhibition balance, interchanges between excitatory and inhibitory roles of neurotransmitters as well as cardiovascular and white matter development across gestational ages, are shown to create sympathetic-parasympathetic synchrony, including the postnatal development of electroencephalogram waves and vagal tone. These occur in developmental milestones detectable in the same time windows (sensitive periods of development) within a convergent systematic progress. This ontogenetic stepwise process is termed “the self-regulation clock” and suggest that this clock is located in the largest connection between the brainstem and the cortex, the corticospinal tract. This novel evidence-based new theory paves the way towards more accurate hypotheses and complex studies of self-regulation and its biological basis, as well as pointing to time windows for interventions in preterm infants. The paper also describes the developing indirect signaling between the suprachiasmatic nucleus and the corticospinal tract. Finally, the paper proposes novel hypotheses for molecular, structural and functional investigation of the “clock” circuitry, including its associations with other biological clocks. This complex circuitry is suggested to be responsible for the developing self-regulatory functions and their neurobehavioral correlates.

Transcultural adaptation and psychometric properties of the International Development and Early Learning Assessment (IDELA) in Brazilian pre-school children

Early childhood is a sensitive period for development, and it is important to use psychometrically sound instruments to assess the child's developmental abilities. The International Development and Early Learning Assessment (IDELA) represents an innovative, feasible and low-cost assessment tool for preschool children that evaluates motor development, pre-numeracy, pre-literacy, and socioemotional development. These areas of development represent “key” skills for early development and school readiness. The objectives of this study were to translate the IDELA to Brazilian Portuguese, to conduct its cultural adaptation to the Brazilian population, to analyze its content validity, to assess its inter-rater reliability, to analyze the internal consistency of its sub-domains and to investigate associations between the child's IDELA scores and sociodemographic characteristics of the family. This was a descriptive, cross-sectional study, in which a sample of 565 preschool children were assessed with the IDELA in the city of Embu das Artes, São Paulo. Results indicated that the IDELA was successfully translated and culturally adapted to the Brazilian population, presenting adequate content validity, good internal consistency of its sub-domains and very high inter-rater reliability. Among the evaluated children, the girls' mean scores were higher than the boys' mean scores; 5-year-old children had higher scores than 4-year-old children; a positive correlation was observed between maternal education and the children's mean scores in the total IDELA, the pre-mathematics and the socioemotional subdomains. In conclusion, the Brazilian version of the IDELA proved to be feasible, adequate and reliable to assess early childhood development and school readiness of preschool age children in Brazil. Future studies could use the IDELA to provide relevant data about the children's development and school readiness in other Brazilian regions that will be useful in the planning of public health and education policies to improve children's integral development and their academic achievement.

The Potential Role of Nutrition in Modulating the Long-Term Consequences of Early-Life Stress.

Stress exposure during sensitive developmental periods lastingly affects brain function and cognition and increases vulnerability to psychopathology later in life, as established in various preclinical and clinical studies. Interestingly, similar patterns are seen in children who suffer from perinatal malnutrition. Stress and malnutrition can act closely aligned and stress and nutrition interact. There is emerging evidence that specific nutritional supplementation during various time windows may ameliorate the long-lasting effects of early-life stress, although possible mechanistic insights in this process are sparsely reported. Understanding how stress exposure in early-life influences brain development, and understanding the role of nutrition in this process, is essential for the development of effective (nutritional) therapies to improve long-term health in children exposed to early-life stress. This is especially important in the situation of preterm birth where both stress exposure and malnutrition are common. Here, we will discuss the programming effects of early-life stress, the possible underlying mechanisms, how nutrients impact on this process, and the promising role of nutrition in modulating (some of) the lasting consequences of early-life stress on brain function and health in adulthood.

Issue Information

Palatogenesis is affected by genetic and environmental insults during sensitive developmental periods. In zebrafish palatogenesis, the knockout of a homeobox transcription factor (mkxa) increases the susceptibility to an inhibitor of Sonic hedgehog signaling (cyclopamine). Further details can be seen in the article by Adachi et al. in this issue. image

ВЗАИМОСВЯЗЬ МОТИВАЦИЙ ЛИЧНОСТИ И СКЛОННОСТИ К ДЕВИАНТНОМУ ПОВЕДЕНИЮ У ПОДРОСТКОВ, ОБУЧАЮЩИХСЯ В УЧРЕЖДЕНИЯХ СРЕДНЕГО ПРОФЕССИОНАЛЬНОГО ОБРАЗОВАНИЯ

The article reflects the connection of motivation with deviant behavior as one of the significant aspects of the study of the problem of adolescents’ deviation. The theoretical approaches presented in the article show that the violation of the motivational sphere of adolescents increases the risk of deviant behavior. The types of such motives are listed in the work. The author pays attention to the study of the relationship between personal motivation and the tendency to deviant behavior of adolescent students of secondary vocational educational institutions with the norm of behavior. On the one hand the adolescence is shown to be a sensitive period of development of the motivational sphere; on the other hand, admission to secondary vocational education organizations acts as a new social situation for a teenager. The ratio of these facts can increase the negative manifestations of deviant behavior. The aim of the study is to establish the relationship between the propensity for deviant behavior and the motives of students’ personality at educational institutions of secondary vocational education. The author describes the methods and results of the study, the purpose of which is to establish the relationship between motivation and the tendency to deviant behavior in adolescent students of vocational educational institutions. The diagnostic methods were the method of J. Nuttin (motivational sphere) and the questionnaire “DAP-P” (tendency to deviant behavior). The sample of subjects consisted of 44 first-year students studying at secondary educational institutions, whose average age is 15.8. Results of the method of J. Nuttin showed the severity of the motive of achievement, cognition, influence, dominance and focus on material values. According to the results of the questionnaire “DAP-P” students have an average level of tendency to deviant behavior. The r-Spearman correlation method has found correlations between the tendency to delinquent behavior as a form of deviant behavior and such motives as aggressiveness, focus on material values, power, dominating. This fact confirms our hypothesis. The analysis of the correspondence of the results obtained by the author with similar scientific research is carried out. Conclusions are drawn about the theoretical and practical significance of the work.

KONSTRUKTIVISTIČKI PRISTUP UČENJU DECE PREDŠKOLSKOG UZRASTA

Constructivism, as a theory about learning and knowledge, is the subject of a large number of both theoretical and empirical researches. Views on the values of constructivism range from advocacy to refutation. What is characteristic of modern educational policy is the focus on productivity, activity and knowledge that will be applicable in real life circumstances. The basic idea of constructivism is based on these assumptions. In this paper, we deal with the question of why this approach is extremely important in early childhood. The preschool period is one of the most sensitive periods in development. It is characterized by numerous regularities and specifics, which should be followed within every program intended for the upbringing and education of children in the preschool period. Preschool children are characterized by curiosity, desire to learn, activity but also short-term maintenance of intentional attention, rapid fatigue and loss of interest in things that are familiar to them. Therefore, the constructivist approach in this period is very suitable, because it does not insist on imposing certain knowledge, but suggests an activity based on interests. The modern preschool institution has the task of providing children with a favorable social and material environment that will encourage development through activity and gaining experience and thus support the realization of their potential. Keywords: constructivism, preschool education, active learning.

Annual Research Review: A systematic review ofmental health services for emerging adults-moulding a precipice into a smooth passage.

The transition between child and adult services should aim to support young people into the next stage of their life in a way that optimises their function. Yet financial, organisational and procedural barriers to continuity of care often hamper smooth transition between child and adult services. We reviewed studies of transition from child to adult mental health services, focusing on: (a) rates of referrals and referral acceptance; (b) barriers and facilitators of successful transition; (c) continuity of care during and post-transition and (d) service users' experience of transition. Studies were identified through systematic searches of electronic databases: PsycINFO, Medline, Embase and Child Development and Adolescent Studies. Forty-seven papers describing 43 unique studies met inclusion criteria. Service provision is influenced by previous history and funding processes, and the presence or absence of strong primary care, specialist centres of excellence and coordination between specialist and primary care. Provision varies between and within countries, particularly whether services are restricted to 'core' mental health or broader needs. Unsupportive organisational culture, fragmentation of resources, skills and knowledge base undermine the collaborative working essential to optimise transition. Stigma and young people's concerns about peers' evaluation often prompt disengagement and discontinuation of care during transition, leading to worsening of symptoms and later, to service re-entry. Qualitative studies reveal that young people and families find the transition process frustrating and difficult, mainly because of lack of advanced planning and inadequate preparation. Despite increasing research interest over the last decade, transition remains 'poorly planned, executed and experienced'. Closer collaboration between child and adult services is needed to improve the quality of provision for this vulnerable group at this sensitive period of development.

Single-Cell Transcriptional Changes in Hypothalamic Corticotropin-Releasing Factor–Expressing Neurons After Early-Life Adversity Inform Enduring Alterations in Vulnerabilities to Stress

BackgroundMental health and vulnerabilities to neuropsychiatric disorders involve the interplay of genes and environment, particularly during sensitive developmental periods. Early-life adversity (ELA) and stress promote vulnerabilities to stress-related affective disorders, yet it is unknown how transient ELA dictates lifelong neuroendocrine and behavioral reactions to stress. The population of hypothalamic corticotropin-releasing factor (CRF)–expressing neurons that regulate stress responses is a promising candidate to mediate the long-lasting influences of ELA on stress-related behavioral and hormonal responses via enduring transcriptional and epigenetic mechanisms. MethodsCapitalizing on a well-characterized model of ELA, we examined ELA-induced changes in gene expression profiles of CRF-expressing neurons in the hypothalamic paraventricular nucleus of developing male mice. We used single-cell RNA sequencing on isolated CRF-expressing neurons. We determined the enduring functional consequences of transcriptional changes on stress reactivity in adult ELA mice, including hormonal responses to acute stress, adrenal weights as a measure of chronic stress, and behaviors in the looming shadow threat task. ResultsSingle-cell transcriptomics identified distinct and novel CRF-expressing neuronal populations, characterized by both their gene expression repertoire and their neurotransmitter profiles. ELA-provoked expression changes were selective to specific subpopulations and affected genes involved in neuronal differentiation, synapse formation, energy metabolism, and cellular responses to stress and injury. Importantly, these expression changes were impactful, apparent from adrenal hypertrophy and augmented behavioral responses to stress in adulthood. ConclusionsWe uncover a novel repertoire of stress-regulating CRF cell types differentially affected by ELA and resulting in augmented stress vulnerability, with relevance to the origins of stress-related affective disorders.

Involvement of homeobox transcription factor Mohawk in palatogenesis.

Palatogenesis is affected by many factors, including gene polymorphisms and exposure to toxic chemicals during sensitive developmental periods. Cleft palate is one of the most common congenital anomalies, and ongoing efforts to elucidate the molecular mechanisms underlying palatogenesis are providing useful insights to reduce the risk of this disorder. To identify novel potential regulators of palatogenesis, we analyzed public transcriptome datasets from a mouse model of cleft palate caused by selective deletion of transforming growth factor-β (TGFβ) receptor type 2 in cranial neural crest cells. We identified the homeobox transcription factor Mohawk (Mkx) as a gene downregulated in the maxilla of TGFβ knockout mice compared with wild-type mice. To examine the role of mkx in palatogenesis, we used CRISPR/Cas9 editing to generate zebrafish with impaired expression of mkxa and mkxb, the zebrafish homologs of Mkx. We found that mkx crispants expressed reduced levels of gli1, a critical transcription factor in the Sonic hedgehog (SHH) signaling pathway that plays an important role in the regulation of palatogenesis. Furthermore, we found that mkxa-/- zebrafish were more susceptible than mkxa+/+ zebrafish to the deleterious effects of cyclopamine, an inhibitor of SHH signaling, on upper jaw development. These results suggest that Mkx may be involved in palatogenesis regulated by TGFβ and SHH signaling, and that impairment in Mkx function may be related to the etiology of cleft palate.

Multiple metals in children’s deciduous teeth: results from a community-initiated pilot study

BackgroundCharacterizing retrospective exposure to toxicants during multiple early-life developmental periods is challenging, yet critical for understanding developmental effects.ObjectiveTo characterize early-life metal exposure using deciduous teeth in a community concerned about past exposures.MethodsNaturally shed teeth were collected from 30 children ages 5–13 years who resided in Holliston, Massachusetts since conception. We estimated weekly prenatal and postnatal (up to 1 year of age) exposure to 12 metals by measuring dentine concentrations using laser ablation-inductively coupled plasma-mass spectrometry. Multivariable linear mixed models were used to explore sociodemographic, dietary, and behavioral correlates of dentine metal concentrations.ResultsTemporal trends in dentine levels differed by metal. Source of milk during the first year of life was associated with dentine barium (Ba) levels, where being fed predominantly breastmilk was associated with 39% (95% CI: –57%, –13%) lower dentine Ba compared to predominantly formula use. Females had higher prenatal and postnatal dentine Mn and Pb, compared to males (e.g., % difference, postnatal Mn: 122% (17%, 321%); postnatal Pb: 60% (95% CI: –8%, 178%)).SignificanceDeciduous teeth provide retrospective information on dose and timing of early-life metals exposure at high resolution. We demonstrate their utility in a community-based study with known past contamination of drinking water.Impact statementWe conducted a community-initiated pilot study in a community concerned with historical exposure to multiple metals. Using deciduous teeth, a novel noninvasive biomarker, we characterized early-life exposure to 12 metals in approximately weekly increments during sensitive developmental periods, thus demonstrating the utility of this biomarker in communities concerned with past exposures.

Erucic acid exposure during the first year of life-Scenarios with precise food-based dietary guidelines.

Recently, the European Food Safety Authority (EFSA) issued a tolerable daily intake (TDI) for erucic acid, which is mainly found in rapeseed oil. Infants may be exposed to erucic acid from rapeseed oil indirectly through maternal consumption via breastmilk or the fat component in formula, and directly as a part of complementary feeding (CF). To check the safety of infant nutrition, scenarios for erucic acid exposure were calculated based on the daily food amounts of the German dietary guidelines. Information on erucic acid concentrations in foods was obtained from European studies for breastmilk, from EFSA samples for formula powder, and from a representative analysis of rapeseed oil samples in the German retail market. 6 scenarios were calculated for the early milk feeding phase (4 formula feeding, 2 breastfeeding) and 8 scenarios for the later CF phase (5 CF +formula feeding, 3 CF +breastfeeding). Out of the 14 scenarios, only 3 resulted in exposures that were definitively below the TDI (range 4.4.–6.0 mg/kg bodyweight; BW). Assuming either high consumption or high concentration led to high exceedances (range 7.5–26.2 mg/kg BW), especially in case of the new EU limits for formula or vegetable oils (33.6 and 43.2 mg/kg BW, respectively). In our scenarios, high erucic acid exposures occurred during a particularly sensitive developmental period. To definitively weigh the potential risks from erucic acid in infants against nutritional benefits of the dietary recommendations, reliable, timely data on erucic acid in breast milk and formula are needed, similar to those from rapeseed oil in Germany.