ABSTRACT
Measures of physical growth, such as weight and height have long been the predominant outcomes for monitoring child health and evaluating interventional outcomes in public health studies, including those that may impact neurodevelopment. While physical growth generally reflects overall health and nutritional status, it lacks sensitivity and specificity to brain growth and developing cognitive skills and abilities. Psychometric tools, e.g., the Bayley Scales of Infant and Toddler Development, may afford more direct assessment of cognitive development but they require language translation, cultural adaptation, and population norming. Further, they are not always reliable predictors of future outcomes when assessed within the first 12-18 months of a child's life. Neuroimaging may provide more objective, sensitive, and predictive measures of neurodevelopment but tools such as magnetic resonance (MR) imaging are not readily available in many low and middle-income countries (LMICs). MRI systems that operate at lower magnetic fields (< 100mT) may offer increased accessibility, but their use for global health studies remains nascent. The UNITY project is envisaged as a global partnership to advance neuroimaging in global health studies. Here we describe the UNITY project, its goals, methods, operating procedures, and expected outcomes in characterizing neurodevelopment in sub-Saharan Africa and South Asia.
ABSTRACT
Prenatal alcohol exposure (PAE) can affect brain development in early life, but few studies have investigated the effects of PAE on trajectories of white matter tract maturation in young children. Here we used diffusion weighted imaging (DWI) repeated over three time points, to measure the effects of PAE on patterns of white matter microstructural development during the pre-school years. Participants were drawn from the Drakenstein Child Health Study (DCHS), an ongoing birth cohort study conducted in a peri-urban community in the Western Cape, South Africa. A total of 342 scans acquired from 237 children as neonates (N = 82 scans: 30 PAE; 52 controls) and at ages 2-3 (N = 121 scans: 27 PAE; 94 controls) and 6-7 years (N = 139 scans: 45 PAE; 94 controls) were included. Maternal alcohol use during pregnancy and other antenatal covariates were collected from 28 to 32 weeks' gestation. Linear mixed effects models with restricted maxium likelihood to accommodate missing data were implemented to investigate the effects of PAE on fractional anisotropy (FA) and mean diffusivity (MD) in specific white matter tracts over time, while adjusting for child sex and maternal education. We found significant PAE-by-time effects on trajectories of FA development in the left superior cerebellar peduncle (SCP-L: p = 0.001; survived FDR correction) and right superior longitudinal fasciculus (SLF-R: p = 0.046), suggesting altered white matter development among children with PAE. Compared with controls, children with PAE demonstrated a more rapid change in FA in these tracts from the neonatal period to 2-3 years of age, followed by a more tapered trajectory for the period from 2-3 to 6-7 years of age, with these trajectories differing from unexposed control children. Given their supporting roles in various aspects of neurocognitive functioning (i.e., motor regulation, learning, memory, language), altered patterns of maturation in the SCP and SLF may contribute to a spectrum of physical, social, emotional, and cognitive difficulties often experienced by children with PAE. This study highlights the value of repeated early imaging in longitudinal studies of PAE, and focus for early childhood as a critical window of potential susceptibility as well as an opportunity for early intervention.
Subject(s)
Prenatal Exposure Delayed Effects , White Matter , Child , Infant, Newborn , Humans , Child, Preschool , Female , Pregnancy , Diffusion Tensor Imaging/methods , White Matter/diagnostic imaging , South Africa , Cohort Studies , Birth Cohort , Prenatal Exposure Delayed Effects/diagnostic imaging , Longitudinal Studies , Anisotropy , Brain/diagnostic imagingABSTRACT
Child development is strongly influenced by maternal characteristics. Maternal sensitivity, as well as risks to and outcomes of sensitive maternal style, are well studied in industrialised western contexts, but it is unclear if this is the case for other contexts. Sub-Saharan Africa has been subjected to and continues to negotiate socio-economic and psychological sequelae of colonial and race-based politics: exploring the nature and outcomes of early caregiver input in such challenging conditions is imperative. This scoping review thus aims to 1) evaluate the nature and extent of quantified observational assessments of dyadic interactions, with a focus on maternal sensitivity, in Sub-Saharan Africa and 2) ascertain which risk and outcome factors have been examined in relation to maternal sensitivity. Study quality and cross-cultural appropriateness will also be considered. The search using expanded search terms yielded 20 papers -four characterizing maternal sensitivity or style, eight examining maternal sensitivity in relation to risks and outcomes, and eight intervention studies examining efforts to improve maternal sensitivity. Most research was conducted in South Africa - only seven studies were conducted in four other countries. Researchers used a wide array of coding schemes, mostly developed in the west. Ten studies made some adaptations to measures. Language issues and cultural considerations were often not explicitly addressed. Taken together, very limited research on this important topic exists. For the work that does exist, questions around westernized assumptions, language, and appropriateness of measures remain. Substantially more research, informed by both culturally flexible conceptualizations and methodological rigour, is required.
ABSTRACT
Over the past few decades, neuroimaging has become a ubiquitous tool in basic research and clinical studies of the human brain. However, no reference standards currently exist to quantify individual differences in neuroimaging metrics over time, in contrast to growth charts for anthropometric traits such as height and weight1. Here we assemble an interactive open resource to benchmark brain morphology derived from any current or future sample of MRI data ( http://www.brainchart.io/ ). With the goal of basing these reference charts on the largest and most inclusive dataset available, acknowledging limitations due to known biases of MRI studies relative to the diversity of the global population, we aggregated 123,984 MRI scans, across more than 100 primary studies, from 101,457 human participants between 115 days post-conception to 100 years of age. MRI metrics were quantified by centile scores, relative to non-linear trajectories2 of brain structural changes, and rates of change, over the lifespan. Brain charts identified previously unreported neurodevelopmental milestones3, showed high stability of individuals across longitudinal assessments, and demonstrated robustness to technical and methodological differences between primary studies. Centile scores showed increased heritability compared with non-centiled MRI phenotypes, and provided a standardized measure of atypical brain structure that revealed patterns of neuroanatomical variation across neurological and psychiatric disorders. In summary, brain charts are an essential step towards robust quantification of individual variation benchmarked to normative trajectories in multiple, commonly used neuroimaging phenotypes.
Subject(s)
Brain , Longevity , Body Height , Brain/anatomy & histology , Humans , Magnetic Resonance Imaging/methods , NeuroimagingABSTRACT
BACKGROUND: The world has suffered immeasurably during the COVID-19 pandemic. Increased distress and mental and medical health concerns are collateral consequences to the disease itself. The Genes to Mental Health (G2MH) Network consortium sought to understand how individuals affected by the rare copy number variations of 22q11.2 deletion and duplication syndrome, associated with neurodevelopmental/neuropsychiatric conditions, were coping. The article focuses on worry and disruptions in medical care caused by the pandemic. METHODS: The University of Pennsylvania COVID-19 Stressor List and care disruption questions were circulated by 22 advocacy groups in English and 11 other languages. RESULTS: A total of 512 people from 23 countries completed the survey; most were caregivers of affected individuals. Worry about family members acquiring COVID-19 had the highest average endorsed worry, whilst currently having COVID-19 had the lowest rated worry. Total COVID-19 worries were higher in individuals completing the survey towards the end of the study (later pandemic wave); 36% (n = 186) of the sample reported a significant effect on health due to care interruption during the pandemic; 44% of individuals (n = 111) receiving care for their genetic syndrome in a hospital setting reported delaying appointments due to COVID-19 fears; 12% (n = 59) of the sample reported disruptions to treatments; and of those reporting no current disruptions, 59% (n = 269) worried about future disruptions if the pandemic continued. Higher levels of care disruptions were related to higher COVID-19 worries (Ps < 0.005). Minimal differences by respondent type or copy number variation type emerged. CONCLUSIONS: Widespread medical care disruptions and pandemic-related worries were reported by individuals with 22q11.2 syndrome and their family members. Reported worries were broadly consistent with research results from prior reports in the general population. The long-term effects of COVID-19 worries, interruptions to care and hospital avoidance require further study.
Subject(s)
COVID-19 , DNA Copy Number Variations , Caregivers , Chromosomes , Humans , PandemicsABSTRACT
BACKGROUND: Antenatal maternal psychological distress is common in low and middle-income countries (LMIC), but there is a dearth of research on its effect on birth and developmental outcomes in these settings, particularly in Sub-Saharan Africa. This study set out to identify risk factors for antenatal maternal psychological distress and determine whether antenatal maternal psychological distress was associated with infant birth and developmental outcomes, using data from the Drakenstein Child Health Study (DCHS), a birth cohort study in South Africa. METHODS: Pregnant women were enrolled in the DCHS from primary care antenatal clinics. Antenatal maternal psychological distress was measured using the Self-Reporting Questionnaire 20-item (SRQ-20). A range of psychosocial measures, including maternal childhood trauma, depression, and posttraumatic stress disorder (PTSD) were administered. Birth outcomes, including premature birth, weight-for-age z-score and head circumference-for-age z-score, were measured using revised Fenton growth charts. The Bayley III Scales of Infant and Toddler Development was administered at 6 months of age to assess infant development outcomes, including cognitive, language, and motor domains in a subset of n=231. Associations of maternal antenatal psychological distress with psychosocial measures, and with infant birth and developmental outcomes were examined using linear regression models. RESULTS: 961 women were included in this analysis, with 197 (21%) reporting scores indicating the presence of psychological distress. Antenatal psychological distress was associated with maternal childhood trauma, antenatal depression, and PTSD, and inversely associated with partner support. No association was observed between antenatal maternal psychological distress and preterm birth or early developmental outcomes, but antenatal maternal psychological distress was associated with a smaller head circumference at birth (coefficient=-0.30, 95% CI: -0.49; -0.10). CONCLUSION: Antenatal maternal psychological distress is common in LMIC settings and was found to be associated with key psychosocial measures during pregnancy, as well as with adverse birth outcomes, in our study population. These associations highlight the potential value of screening for antenatal maternal psychological distress as well as of developing targeted interventions.
Subject(s)
Child Development/physiology , Pregnancy Complications/psychology , Prenatal Exposure Delayed Effects/psychology , Psychological Distress , Adult , Cohort Studies , Family , Female , Humans , Infant , Infant, Newborn , Pregnancy , Pregnancy Complications/diagnosis , Risk Factors , South Africa , Stress Disorders, Post-Traumatic/diagnosis , Stress Disorders, Post-Traumatic/psychology , Surveys and Questionnaires , Young AdultABSTRACT
PURPOSE: Data relating to the role that Human immunodeficiency virus (HIV) contributes towards seizures in HIV-infected children is limited. The management of seizures in this group is complex due to potential interactions between antiseizure medication and antiretroviral therapies. This study explores the seizure semiology and course of a population of affected children based on questions raised from a previous epidemiological study. METHODS: A retrospective case-control study of all patients presenting to an HIV neurology clinic between 2008-2015 was conducted. A multinomial logistic regression model was used to identify risk factors for seizure occurrence in HIV-infected children, as well as factors associated with seizure control. RESULTS: Of 227 HIV-infected children (median 82 months, interquartile range 41-109), 52 (23%) reported a past or present history of seizures. Prior bacterial meningitis (p = 0.03, OR 12.5, 95% CI 1.2-136.1), cerebrovascular accident (CVA, p = 0. 005, OR 8.1, 95% CI 1.9-34.9) and or tuberculous meningitis (TBM, p = 0.0004) was associated with an increased risk of seizures in HIV-infected children. Generalised tonic-clonic seizures were the predominant seizure type (64%) with the majority caused by an infectious aetiology (62%). Thirty-two (62%) of these patients had epilepsy in-line with the latest diagnostic criteria. HIV-infected children with epilepsy who were treated with efavirenz were more likely to have poor seizure control (OR 23.1 95% CI 3.4-159.6, p = 0.0001). CONCLUSIONS: This study provides new data highlighting the complex clinical presentation and management challenges of HIV-infected children with seizures.
Subject(s)
HIV Infections/complications , HIV Infections/epidemiology , Seizures/complications , Seizures/epidemiology , Adolescent , Anticonvulsants/therapeutic use , Antiviral Agents/therapeutic use , Case-Control Studies , Child , Child, Preschool , Female , HIV Infections/diagnostic imaging , HIV Infections/drug therapy , Humans , Infant , Male , Neuroimaging , Risk Factors , Seizures/diagnostic imaging , Seizures/drug therapy , South Africa/epidemiology , Statistics, NonparametricABSTRACT
In utero exposure to alcohol leads to a spectrum of fetal alcohol related disorders (FASD). However, few studies used have used proton magnetic resonance spectroscopy ((1)H-MRS) to understand how neurochemical disturbances relate to the pathophysiology of FASD. Further, no studies to date have assessed brain metabolites in infants exposed to alcohol in utero. We hypothesize that neonates exposed to alcohol in utero will show decreased glutamatergic activity, pre-emptive of their clinical diagnosis or behavioural phenotype. Single voxel (1)H-MRS data, sampled in parietal white and gray matter, were acquired from 36 neonates exposed to alcohol in utero, and 31 control unexposed healthy neonates, in their 2nd-4th week of life. Metabolites relative to creatine with phosophocreatine and metabolites absolute concentrations using a water reference are reported. Male infants exposed to alcohol in utero were found to have reduced concentration of glutamate with glutamine (Glx) in their parietal white matter (PWM), compared to healthy male infants (p = 0.02). Further, male infants exposed to alcohol in utero had reduced concentration and ratio for glutamate (Glu) in their PWM (p = 0.02), compared to healthy male infants and female infants exposed to alcohol in utero. Female infants showed higher relative Glx and Glu ratios for parietal gray matter (PGM, p < 0.01), compared to male infants. We speculate that the decreased Glx and Glu concentrations in PWM are a result of delayed oligodendrocyte maturation, which may be a result of dysfunctional thyroid hormone activity in males exposed to alcohol in utero. Further study is required to elucidate the relationship between Glx and Glu, thyroid hormone activity, and oligodendrocyte maturation in infants exposure to alcohol in utero.
Subject(s)
Alcohol Drinking/metabolism , Glutamic Acid/metabolism , Magnetic Resonance Spectroscopy/methods , Prenatal Exposure Delayed Effects/metabolism , Sex Characteristics , White Matter/metabolism , Alcohol Drinking/adverse effects , Cohort Studies , Female , Humans , Infant, Newborn , Male , Pregnancy , Prenatal Exposure Delayed Effects/diagnosis , Protons , White Matter/pathologyABSTRACT
BACKGROUND: Early life psychobiological and psychosocial factors play a key role in influencing child health outcomes. Longitudinal studies may help elucidate the relevant risk and resilience profiles, and the underlying mechanisms that impact on child health, but there is a paucity of birth cohort data from low and middle-income countries (LMIC). We describe the rationale for and present baseline findings from the psychosocial component of the Drakenstein Child Health Study (DCHS). METHODS: We review the psychosocial measures used in the DCHS, a multidisciplinary birth cohort study in a peri-urban area in South Africa, and provide initial data on psychological distress, depression, substance use, and exposure to traumatic stressors and intimate partner violence (IPV). These and other measures will be assessed longitudinally in mothers in order to investigate associations with child neurodevelopmental and health outcomes. RESULTS: Baseline psychosocial data is presented for mothers (n=634) and fathers (n=75) who have completed antenatal assessments to date. The sample of pregnant mothers is characterized by multiple psychosocial risk factors, including a high prevalence of psychological distress and depression, high levels of substance use, and high exposure to traumatic stressors and IPV. DISCUSSION: These data are consistent with prior South African studies which have documented a high prevalence of a multitude of risk factors during pregnancy. Further longitudinal assessment of mothers and children may clarify the underlying psychobiological and psychosocial mechanisms which impact on child health, and so inform clinical and public health interventions appropriate to the South African and other LMIC contexts.
Subject(s)
Child Abuse/psychology , Child Health , Mental Disorders/epidemiology , Mother-Child Relations , Socioeconomic Factors , Stress, Psychological/epidemiology , Child , Cohort Studies , Female , Humans , Male , Pneumonia/epidemiology , Pneumonia/etiology , Pregnancy , Prenatal Care/statistics & numerical data , Risk Factors , South Africa/epidemiologyABSTRACT
We report the first documented case of endocarditis associated with Bartonella clarridgeiae in any species. B. clarridgeiae was identified as a possible etiological agent of human cat scratch disease. Infective vegetative valvular aortic endocarditis was diagnosed in a 2.5-year-old male neutered boxer. Historically, the dog had been diagnosed with a systolic murmur at 16 months of age and underwent balloon valvuloplasty for severe valvular aortic stenosis. Six months later, the dog was brought to a veterinary hospital with an acute third-degree atrioventricular block and was diagnosed with infective endocarditis. The dog died of cardiopulmonary arrest prior to pacemaker implantation. Necropsy confirmed severe aortic vegetative endocarditis. Blood culture grew a fastidious, gram-negative organism 8 days after being plated. Phenotypic and genotypic characterization of the isolate, including partial sequencing of the citrate synthase (gltA) and 16S rRNA genes indicated that this organism was B. clarridgeiae. DNA extraction from the deformed aortic valve and the healthy pulmonic valve revealed the presence of B. clarridgeiae DNA only from the diseased valve. No Borrelia burgdorferi or Ehrlichia sp. DNA could be identified. Using indirect immunofluorescence tests, the dog was seropositive for B. clarridgeiae and had antibodies against Ehrlichia phagocytophila but not against Ehrlichia canis, Ehrlichia ewingii, B. burgdorferi, or Coxiella burnetii.
Subject(s)
Aortic Valve/microbiology , Bartonella Infections/veterinary , Bartonella/isolation & purification , Dog Diseases/microbiology , Endocarditis, Bacterial/veterinary , Animals , Antibodies, Bacterial/blood , Aortic Valve/pathology , Bartonella/classification , Bartonella/genetics , Bartonella/immunology , Bartonella Infections/microbiology , DNA, Bacterial/analysis , Dogs , Endocarditis, Bacterial/microbiology , Male , Polymerase Chain ReactionABSTRACT
The enzyme 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (HMG-R) is the major rate-limiting enzyme of the mevalonate pathway in many organisms, including yeasts. In the yeast Saccharomyces cerevisiae, there are two isoenzymes of HMG-R (Hmg1p and Hmg2p). Both consist of an anchoring transmembrane domain and a catalytic domain. We have removed the known controlling features of HMG-R by overproducing the catalytic domain of Hmg1p. This overproduction leads to an enhancement of squalene production, implying that HMG-R has been deregulated. The enhancement is apparent under semianaerobic and aerobic conditions. Despite the increase in squalene production, the amount of ergosterol produced by the HMG-R-overproducing yeast was not increased. This result suggests the presence of another regulatory step between squalene and ergosterol formation. Squalene levels generated by cells overproducing the catalytic domain of HMG-R were estimated to be up to 10 times those produced by wild-type cells. The enhancement in squalene production coincided with a reduction in growth rate. This reduction may be a direct consequence of the buildup of high concentrations of squalene and presqualene intermediates of the pathway.