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Threat sensitivity, an individual difference construct reflecting variation in responsiveness to threats of various types, predicts physiological reactivity to aversive stimuli and shares heritable variance with anxiety disorders in adults. However, no research has been conducted yet with youth to examine the heritability of threat sensitivity or evaluate the role of genetic versus environmental influences in its relations with mental health problems. The current study addressed this gap by evaluating the psychometric properties of a measure of this construct, the 20-item Trait Fear scale (TF-20), and examining its phenotypic and genotypic correlations with different forms of psychopathology in a sample of 346 twin pairs (121 monozygotic), aged 9–14 years. Analyses revealed high internal consistency and test-retest reliability for the TF-20. Evidence was also found for its convergent and discriminant validity in terms of phenotypic and genotypic correlations with measures of fear-related psychopathology. By contrast, the TF-20’s associations with depressive conditions were largely attributable to environmental influences. Extending prior work with adults, current study findings provide support for threat sensitivity as a genetically-influenced liability for phobic fear disorders in youth.
Aerosol-cloud interactions contribute significant uncertainty to modern climate model predictions. Analysis of complex observed aerosol-cloud parameter relationships is a crucial piece of reducing this uncertainty. Here, we apply two machine learning methods to explore variability in in-situ observations from the NASA ACTIVATE mission. These observations consist of flights over the Western North Atlantic Ocean, providing a large repository of data including aerosol, meteorological, and microphysical conditions in and out of clouds. We investigate this dataset using principal component analysis (PCA), a linear dimensionality reduction technique, and an autoencoder, a deep learning non-linear dimensionality reduction technique. We find that we can reduce the dimensionality of the parameter space by more than a factor of 2 and verify that the deep learning method outperforms a PCA baseline by two orders of magnitude. Analysis in the low dimensional space of both these techniques reveals two consistent physically interpretable regimes—a low pollution regime and an in-cloud regime. Through this work, we show that unsupervised machine learning techniques can learn useful information from in-situ atmospheric observations and provide interpretable results of low-dimensional variability.
Objectives/Goals: This poster discusses key methodological and theoretical issues in translation and implementation for improving HPV vaccine recommendations in clinics serving rural communities. Methods/Study Population: Leveraging implementation science, the study of how to improve the uptake of evidence-based practices, this pilot study uses a mixed-methods effectiveness-implementation design to engage local experts in identifying a bundle of locally-tailored implementation strategies to facilitate uptake of evidence-based HPV vaccine recommendations. In partnership with the University of Arkansas for Medical Sciences Rural Research Network, we will follow an evidence-based quality improvement process to develop locally tailored implementation strategies, which we will then evaluate for acceptability, feasibility, and effectiveness. Results/Anticipated Results: This study aims to generate actionable insights into the design and implementation of tailored, evidence-based communication strategies that can be scaled to improve HPV vaccine uptake in rural communities. Findings from this pilot study will be used to support a future full-scale Hybrid-Type 3 effectiveness-implementation trial to evaluate the bundle of tailored implementation strategies. Discussion/Significance of Impact: By addressing the rural-specific determinants of evidence-based HPV vaccine recommendations, this research will contribute to a deeper understanding of how to support high-quality, evidence-based provider recommendations in rural, underserved communities, and will mitigate rural disparities in HPV-related cancers.
The diets of children in the UK are suboptimal(1), which may influence their immediate and future health and well-being(2). Schools offer convenient and prolonged access to children from diverse backgrounds, thus interventions within this setting have been suggested as a means to promote diet and health outcomes among this population(3). This study explored the effects of Project Daire(4), a school-based food intervention, on children’s diet diversity and diet quality as well as their attitudes towards health behaviours.
A factorial design cluster randomized controlled trial was conducted. Fifteen primary schools in Northern Ireland were randomized into one of four 6-month intervention arms: Nourish, Engage, Nourish and Engage or Control (Delayed). The Nourish intervention modified the school food environment, provided food-related experiences and increased access to local foods. The Engage intervention included educational activities on nutrition, food and agriculture. Data on food consumption at home, school and/or in total over a 24-hour period were collected using ageappropriate food frequency questionnaires at baseline, with follow-up at 6-months. Diet diversity score (DDS) and diet quality score (DQS) were developed based on adherence to the Eatwell Guide. Additionally, a Health Attitudes and Behaviour measure assessed 10-11 year old children’s attitudes towards importance of various health behaviours at both time points. Linear and logistic regression models were used to examine intervention effects and to account for school clustering.
A total of 445 children aged 6-7 and 458 aged 10-11 years old completed the trial. Results indicated that children aged 10-11 year old who received the Nourish intervention demonstrated higher school DDS (adjusted mean difference=2.79, 95% CI 1.40 – 4.19; p = 0.001) and total DDS (adjusted mean difference=1.55, 95% CI 0.66 – 2.43, p = 0.002) compared to their counterparts who did not. Subgroup analyses revealed that the increases in school DDS among 10-11 year old children in the Nourish group were apparent in both boys and girls (Boys: adjusted mean difference=2.4 95% CI 0.1 – 4.7, p = 0.04; Girls: adjusted mean difference=3.1 95% CI 1.6 – 4.6, p = 0.001). However, the increase in total DDS remained statistically significant only among girls, with an adjusted mean difference of 1.9 (95% CI 1.1-2.7, p<0.001). No statistically significant changes in DQS were detected in either age group. High levels of positive attitudes towards health behaviours were observed at baseline, with no clinically significant effects of either the Nourish or Engage interventions detected during the follow-up period.
The multi-component approach of the Nourish intervention, addressing both food provision and environment, showed promise in promoting diet diversity. Further research is warranted to develop sustainable implementation strategies for Daire, to explore additional intervention components to impact other outcomes, including diet quality, and to evaluate long-term effectiveness.
Identifying persons with HIV (PWH) at increased risk for Alzheimer’s disease (AD) is complicated because memory deficits are common in HIV-associated neurocognitive disorders (HAND) and a defining feature of amnestic mild cognitive impairment (aMCI; a precursor to AD). Recognition memory deficits may be useful in differentiating these etiologies. Therefore, neuroimaging correlates of different memory deficits (i.e., recall, recognition) and their longitudinal trajectories in PWH were examined.
Design:
We examined 92 PWH from the CHARTER Program, ages 45–68, without severe comorbid conditions, who received baseline structural MRI and baseline and longitudinal neuropsychological testing. Linear and logistic regression examined neuroanatomical correlates (i.e., cortical thickness and volumes of regions associated with HAND and/or AD) of memory performance at baseline and multilevel modeling examined neuroanatomical correlates of memory decline (average follow-up = 6.5 years).
Results:
At baseline, thinner pars opercularis cortex was associated with impaired recognition (p = 0.012; p = 0.060 after correcting for multiple comparisons). Worse delayed recall was associated with thinner pars opercularis (p = 0.001) and thinner rostral middle frontal cortex (p = 0.006) cross sectionally even after correcting for multiple comparisons. Delayed recall and recognition were not associated with medial temporal lobe (MTL), basal ganglia, or other prefrontal structures. Recognition impairment was variable over time, and there was little decline in delayed recall. Baseline MTL and prefrontal structures were not associated with delayed recall.
Conclusions:
Episodic memory was associated with prefrontal structures, and MTL and prefrontal structures did not predict memory decline. There was relative stability in memory over time. Findings suggest that episodic memory is more related to frontal structures, rather than encroaching AD pathology, in middle-aged PWH. Additional research should clarify if recognition is useful clinically to differentiate aMCI and HAND.
Flumioxazin and S-metolachlor are widely used in conventional sweetpotato production in North Carolina and other states; however, some growers have recently expressed concerns about potential effects of these herbicides on sweetpotato yield and quality. Previous research indicates that activated charcoal has the potential to reduce herbicide injury. Field studies were conducted in 2021 and 2022 to determine whether flumioxazin applied preplant and S-metolachlor applied before and after transplanting negatively affect sweetpotato yield and quality when activated charcoal is applied with transplant water. The studies evaluated five herbicide treatments and two activated charcoal treatments. Herbicide treatments included two flumioxazin rates, one S-metolachlor rate applied immediately before and immediately after transplanting, and no herbicide. Charcoal treatments consisted of activated charcoal applied at 9 kg ha−1, and no charcoal. No visual injury from herbicides or charcoal was observed. Likewise, no effect of herbicide or charcoal treatment on no. 1, marketable (sum of no. 1 and jumbo grades), or total yield (sum of canner, no. 1, and jumbo grades) was observed. Additionally, shape analysis conducted on calculated length-to-width ratio (LWR) for no. 1 sweetpotato roots found no effect from flumioxazin at either rate on sweetpotato root shape. However, both S-metolachlor treatments resulted in lower LWR of no. 1 sweetpotato roots in 2021. Results are consistent with prior research and indicate that flumioxazin and S-metolachlor are safe for continued use on sweetpotato at registered rates.
Neurocognitive dysfunction is a transdiagnostic finding in psychopathology, but relationships among cognitive domains and general and specific psychopathology dimensions remain unclear. This study aimed to examine associations between cognition and psychopathology dimensions in a large youth cohort.
Method
The sample (N = 9350; age 8–21 years) was drawn from the Philadelphia Neurodevelopmental Cohort. Data from structured clinical interviews were modeled using bifactor confirmatory factor analysis (CFA), resulting in an overall psychopathology (‘p’) factor score and six orthogonal psychopathology dimensions: dysphoria/distress, obsessive-compulsive, behavioral/externalizing, attention-deficit/hyperactivity, phobias, and psychosis. Neurocognitive data were aggregated using correlated-traits CFA into five factors: executive functioning, memory, complex cognition, social cognition, and sensorimotor speed. We examined relationships among specific and general psychopathology dimensions and neurocognitive factors.
Results
The final model showed both overall and specific associations between cognitive functioning and psychopathology, with acceptable fit (CFI = 0.91; TLI = 0.90; RMSEA = 0.024; SRMR = 0.054). Overall psychopathology and most psychopathology dimensions were negatively associated with neurocognitive functioning (phobias [p < 0.0005], behavioral/externalizing [p < 0.0005], attention-deficit/hyperactivity [p < 0.0005], psychosis [p < 0.0005 to p < 0.05]), except for dysphoria/distress and obsessive-compulsive symptoms, which were positively associated with complex cognition (p < 0.05 and p < 0.01, respectively).
Conclusion
By modeling a broad range of cognitive and psychopathology domains in a large, diverse sample of youth, we found aspects of neurocognitive functioning shared across clinical phenotypes, as well as domain-specific patterns. Findings support transdiagnostic examination of cognitive performance to parse variability in the link between neurocognitive functioning and clinical phenotypes.
Fruit and vegetable intakes are major modifiable determinants of risk for non-communicable disease(1), yet intake levels remain low(2) and multiple barriers (cost, access, perishability, preparation skills) exist(3,4). 100% fruit and vegetable juices contain key micronutrients and bioactive compounds (5–7) and may help circumvent these barriers to consumption(6,7). However, their role in dietary guidelines and models of healthy eating remains controversial due to their free sugars and reduced dietary fibre content, relative to whole fruits and vegetables(6,7). Therefore, we conducted a systematic umbrella review of systematic literature reviews (SLRs) with meta-analyses assessing the relationships between 100% juice consumption and human health outcomes. Four databases (Medline, Cochrane Library, EMBASE, and CINAHL) were systematically searched for SLRs with meta-analyses of human prospective cohort, case-control, and intervention studies examining the relationship between 100% juice and any health outcome through to 20th October 2022. Screening (Covidence), quality (GRADE)(8), risk of bias (ROBIS)(9) and content overlap (corrected covered area(10)) tools were applied, and extracted data were narratively synthesised. The protocol was pre-registered (PROSPERO) and conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklists. 15 SLRs on 100% fruit juice including 51 primary meta-analyses, 6 dose-response analyses, and 87 sub-analyses were eligible for inclusion. No eligible studies on vegetable juice were found. Included studies represented data from almost 2 million subjects with a range of doses (50-1200mL/day) and timeframes (hours to years). Significant improvements in health outcomes were found in 19.6% of included meta-analyses (blood pressure, flow-mediated dilation, IL-6, c-reactive protein, and stroke mortality), and increased disease risks were found in 5.9% of included meta-analyses (CVD mortality, prostate cancer, and type II diabetes). The remainder (74.5%) found no significant difference (blood lipids, weight, liver function, metabolic markers, colorectal and breast cancers, and multiple inflammatory markers). The ROBIS quality assessment rated nine SLRs as low risk of bias, three as unclear and three as high. Using GRADE, confidence in the body of evidence ranged from very low (27 primary and 79 secondary meta-analyses) to low (19 primary and 13 secondary meta-analyses), and medium (4 primary and one secondary meta-analyses.) Findings show 100% juice consumption has limited risks of harm and some potential benefits, over a broad range of doses, including some that are relatively high, and time periods. The positive associations between 100% juice consumption and specific health outcomes relevant to population health may be explained by multiple mechanisms, including the vitamin, mineral, and bioactive contents. The balance of evidence suggests that 100% may have a neutral or beneficial place in general, population-level dietary guidelines.
Greenhouse trials were conducted to determine the response of stevia to reduced-risk synthetic and nonsynthetic herbicides applied over-the-top post-transplant. In addition, field trials were conducted with stevia grown in a polyethylene mulch production system to determine crop response and weed control in planting holes to reduced-risk synthetic and nonsynthetic herbicides applied post-transplant directed. Treatments included caprylic acid plus capric acid, clove oil plus cinnamon oil, d-limonene, acetic acid (200 grain), citric acid, pelargonic acid, eugenol, ammonium nonanoate, and ammoniated soap of fatty acids. Stevia yield (dry aboveground biomass) in the greenhouse was reduced by all herbicide treatments. Citric acid and clove oil plus cinnamon oil were the least injurious, reducing yield by 16% to 20%, respectively. In field studies, d-limonene, pelargonic acid, ammonium nonanoate, and ammoniated soap of fatty acids controlled Palmer amaranth (>90% 1 wk after treatment (WAT). In field studies caprylic acid plus capric acid, pelargonic acid, and ammonium nonanoate caused >30% injury to stevia plants at 2 WAT, and d-limonene, citric acid, acetic acid, and ammoniated soap of fatty acids caused 18% to 25% injury 2 WAT. Clove oil plus cinnamon oil and eugenol caused <10% injury. Despite being injurious, herbicides applied in the field did not reduce yield compared to the nontreated check. Based upon yield data, these herbicides have potential for use in stevia; however, these products could delay harvest if applied to established stevia. In particular, clove oil plus cinnamon oil has potential for use for early-season weed management for organic production systems. The application of clove oil plus cinnamon oil over-the-top resulted in <10% injury 28 d after treatment (DAT) in the greenhouse and 3% injury 6 WAT postemergence-directed in the field. In addition, this treatment provided 95% control of Palmer amaranth 4 WAT.
This article examines the development, early operation and subsequent failure of the Tot-Kolowa Red Cross irrigation scheme in Kenya’s Kerio Valley. Initially conceived as a technical solution to address regional food insecurity, the scheme aimed to scale up food production through the implementation of a fixed pipe irrigation system and the provision of agricultural inputs for cash cropping. A series of unfolding circumstances, however, necessitated numerous modifications to the original design as the project became increasingly entangled with deep and complex histories of land use patterns, resource allocation and conflict. Failure to understand the complexity of these dynamics ultimately led to the project’s collapse as the region spiralled into a period of significant unrest. In tracing these events, we aim to foreground the lived realities of imposed development, including both positive and negative responses to the scheme’s participatory obligations and its wider impact on community resilience.
To cope with homonegativity-generated stress, gay, bisexual and other men who have sex with men (GBM) use more mental health services (MHS) compared with heterosexual men. Most previous research on MHS among GBM uses data from largely white HIV-negative samples. Using an intersectionality-based approach, we evaluated the concomitant impact of racialization and HIV stigma on MHS use among GBM, through the mediating role of perceived discrimination (PD).
Methods
We used baseline data from 2371 GBM enrolled in the Engage cohort study, collected between 2017 and 2019, in Montreal, Toronto and Vancouver, using respondent-driven sampling. The exposure was GBM groups: Group 1 (n = 1376): white HIV-negative; Group 2 (n = 327): white living with HIV; Group 3 (n = 577): racialized as non-white HIV-negative; Group 4 (n = 91): racialized as non-white living with HIV. The mediator was interpersonal PD scores measured using the Everyday Discrimination Scale (5-item version). The outcome was MHS use (yes/no) in the prior 6 months. We fit a three-way decomposition of causal mediation effects utilizing the imputation method for natural effect models. We obtained odds ratios (ORs) for pure direct effect (PDE, unmediated effect), pure indirect effect (PIE, mediated effect), mediated interaction effect (MIE, effect due to interaction between the exposure and mediator) and total effect (TE, overall effect). Analyses controlled for age, chronic mental health condition, Canadian citizenship, being cisgender and city of enrolment.
Results
Mean PD scores were highest for racialized HIV-negative GBM (10.3, SD: 5.0) and lowest for white HIV-negative GBM (8.4, SD: 3.9). MHS use was highest in white GBM living with HIV (GBMHIV) (40.4%) and lowest in racialized HIV-negative GBM (26.9%). Compared with white HIV-negative GBM, white GBMHIV had higher TE (OR: 1.71; 95% CI: 1.27, 2.29) and PDE (OR: 1.68; 95% CI: 1.27, 2.24), and racialized HIV-negative GBM had higher PIE (OR: 1.09; 95% CI: 1.02, 1.17). Effects for racialized GBMHIV did not significantly differ from those of white HIV-negative GBM. MIEs across all groups were comparable.
Conclusions
Higher MHS use was observed among white GBMHIV compared with white HIV-negative GBM. PD positively mediated MHS use only among racialized HIV-negative GBM. MHS may need to take into account the intersecting impact of homonegativity, racism and HIV stigma on the mental health of GBM.
Older people with HIV (PWH) are at-risk for Alzheimer’s disease (AD) and its precursor, amnestic mild cognitive impairment (aMCI). Identifying aMCI among PWH is challenging because memory impairment is also common in HIV-associated neurocognitive disorders (HAND). The neuropathological hallmarks of aMCI/AD are amyloid-ß42 (Aß42) plaque and phosphorylated tau (p-tau) accumulation. Neurofilament light chain protein (NfL) is a marker of neuronal injury in AD and other neurodegenerative diseases. In this study, we assessed the prognostic value of the CSF AD pathology markers of lower Aß42, and higher p-tau, p-tau/Aß42 ratio, and NfL levels to identify an aMCI-like profile among older PWH and differentiating it from HAND. We assessed the relationship between aMCI and HAND diagnosis and AD biomarker levels
Participants and Methods:
Participants included 74 PWH (Mean age=48 [SD=8.5]; 87.4% male, 56.5% White) from the National NeuroAIDS Tissue Consortium (NNTC). CSF Aß42, Aß40, p-tau and NfL were measured by commercial immunoassay. Participants completed a neurocognitive evaluation assessing the domains of learning, recall, executive function, speed of information processing, working memory, verbal fluency, and motor. Memory domains were assessed with the Hopkins Verbal Learning Test-Revised and the Brief Visuospatial Memory Test-Revised, and aMCI was defined as impairment (<1.0 SD below normative mean) on two or more memory outcomes among HVLT-R and BVMT-R learning, delayed recall and recognition with at-least one recognition impairment required. HAND was defined as impairment (<1.0 SD below normative mean) in 2 or more cognitive domains. A series of separate linear regression models were used to examine how the levels of CSF p-tau, Aß42, p-tau/Aß42 ratio, and NfL relate to aMCI and HAND status while controlling for demographic variables (age, gender, race and education). Covariates were excluded from the model if they did not reach statistical significance.
Results:
58% percent of participants were diagnosed with HAND, 50.5% were diagnosed with aMCI. PWH with aMCI had higher levels of CSF p-tau/Aß42 ratio compared to PWH without aMCI (ß=.222, SE=.001, p=.043) while controlling for age (ß=.363, p=.001). No other AD biomarker significantly differed by aMCI or HAND status.
Conclusions:
Our results indicate that the CSF p-tau/Aß42 ratio relates specifically to an aMCI-like profile among PWH with high rates of cognitive impairment across multiple domains in this advanced HIV disease cohort. Thus, the p-tau/Aß42 ratio may have utility in disentangling aMCI from HAND and informing the need for further diagnostic procedures and intervention. Further research is needed to fully identify, among a broader group of PWH, who is at greatest risk for aMCI/AD and whether there is increased risk for aMCI/AD among PWH as compared to those without HIV.
Among people with HIV (PWH), the apolipoprotein e4 (APOE-e4) allele, a genetic marker associated with Alzheimer’s disease (AD), and self-reported family history of dementia (FHD), considered a proxy for higher AD genetic risk, are independently associated with worse neurocognition. However, research has not addressed the potential additive effect of FHD and APOE-e4 on global and domain-specific neurocognition among PWH. Thus, the aim of the current investigation is to examine the associations between FHD, APOE-e4, and neurocognition among PWH.
Participants and Methods:
283 PWH (Mage=50.9; SDage=5.6) from the CNS HIV Anti-Retroviral Therapy Effects Research (CHARTER) study completed comprehensive neuropsychological and neuromedical evaluations and underwent APOE genotyping. APOE status was dichotomized into APOE-e4+ and APOE-e4-. APOE-e4+ status included heterozygous and homozygous carriers. Participants completed a free-response question capturing FHD of a first- or second-degree relative (i.e., biologic parent, sibling, children, grandparent, grandchild, uncle, aunt, nephew, niece, half-sibling). A dichotomized (yes/no), FHD variable was used in analyses. Neurocognition was measured using global and domain-specific demographically corrected (i.e., age, education, sex, race/ethnicity) T-scores. t-tests were used to compare global and domain-specific demographically-corrected T-scores by FHD status and APOE-e4 status. A 2x2 factorial analysis of variance (ANOVA) was used to model the interactive effects of FHD and APOE-e4 status. Tukey’s HSD test was used to follow-up on significant ANOVAs.
Results:
Results revealed significant differences by FHD status in executive functioning (t(281)=-2.3, p=0.03) and motor skills (t(278)=-2.0, p=0.03) such that FHD+ performed worse compared to FHD-. Differences in global neurocognition by FHD status approached significance (t(281)=-1.8, p=.069). Global and domain-specific neurocognitive performance were comparable among APOE-e4 carriers and noncarriers (ps>0.05). Results evaluating the interactive effects of FHD and APOE-e4 showed significant differences in motor skills (F(3)=2.7, p=0.04) between the FHD-/APOE-e4+ and FHD+/APOE-e4- groups such that the FHD+/APOE-e4- performed worse than the FHD-/APOE-e4+ group (p=0.02).
Conclusions:
PWH with FHD exhibited worse neurocognitive performance within the domains of executive functioning and motor skills, however, there were no significant differences in neurocognition between APOE-e4 carriers and noncarriers. Furthermore, global neurocognitive performance was comparable across FHD/APOE-e4 groups. Differences between the FHD-/APOE-e4+ and FHD+/APOE-e4- groups in motor skills were likely driven by FHD status, considering there were no independent effects of APOE-e4 status. This suggests that FHD may be a predispositional risk factor for poor neurocognitive performance among PWH. Considering FHD is easily captured through self-report, compared to blood based APOE-e4 status, PWH with FHD should be more closely monitored. Future research is warranted to address the potential additive effect of FHD and APOE-e4 on rates of global and domain-specific neurocognitive decline and impairment over time among in an older cohort of PWH, where APOE-e4 status may have stronger effects.
Children born to mothers infected with human immunodeficiency virus (HIV) during pregnancy experience increased risk of neurocognitive impairment. In Botswana, HIV infection is common, but standardized cognitive testing is limited. The Penn Computerized Neurocognitive Battery (PennCNB) is a widely used cognitive test battery that streamlines evaluation of neurocognitive functioning. Our group translated and culturally adapted the PennCNB for use among children and adolescents in this high-burden, low-resource setting. The current study examined the construct validity and sensitivity to HIV infection and exposure of the culturally adapted PennCNB among a cohort of HIV-affected children and adolescents in Gaborone, Botswana.
Participants and Methods:
628 school-aged children aged 7-17 years (n=223 children living with HIV [HIV+]; n=204 HIV exposed, uninfected [HEU]; and 201 HIV unexposed, uninfected [HUU]) completed the PennCNB. Participants were recruited from a clinic specializing in the care and treatment of HIV+ children and adolescents in Gaborone, Botswana, as well as from local schools. Confirmatory factor analyses were performed on efficiency measures for 13 PennCNB tests. Multiple regressions examined associations between HIV and neurocognitive functioning while controlling for age and sex. Multivariate normative comparisons were used to examine rates of overall cognitive impairment by comparing individual profiles of test scores to the multivariate distribution of test scores using age-normed data from the HUU group.
Results:
Confirmatory factor analysis supported four hypothesized neurocognitive domains: executive functioning, episodic memory, complex cognition, and sensorimotor/processing speed. As expected, there were main effects of age on cognitive performance across all domains (ps < .001), and there were small sex differences, with females performing better in executive functioning and males performing better on visuospatial processing. Children and adolescents living with HIV performed significantly worse than HUU across all domains (ps < .001), with the largest effect sizes on measures of abstraction, working memory, and processing speed. HEU also performed worse than HUU across several domains, with smaller effect sizes. Multivariate normative comparisons indicated that 27% of the HIV+ group evidenced global neurocognitive impairment.
Conclusions:
Overall, results support the validity of a neurocognitive battery adapted for use in Botswana, a non-Western, resource-limited setting. Results indicated that the adapted battery applied to children and adolescents with limited computer familiarity had a similar factor structure as in Western settings, indicating that the PennCNB appeared to assess the hypothesized neurocognitive domains. Hypothesized associations with age and sex supported the battery’s construct validity. Moreover, the battery appears to be sensitive to cognitive impairments associated with perinatally-acquired HIV and in utero HIV-related exposures, as it discriminated between the HUU, HIV+, and HEU groups. Differences were found in specific domains and in detection of overall impairment, including approximately one quarter of children and adolescents living with HIV in this cohort evidencing global neurocognitive impairment. Together, these results provide evidence that the PennCNB could serve as a useful tool for the assessment of neurocognitive functioning in school-aged children and adolescents from Botswana and, potentially, other resource-limited settings.
Many people with HIV (PWH) are at risk for age-related neurodegenerative disorders such as Alzheimer’s disease (AD). Studies on the association between cognition, neuroimaging outcomes, and the Apolipoprotein E4 (APOE4) genotype, which is associated with greater risk of AD, have yielded mixed results in PWH; however, many of these studies have examined a wide age range of PWH and have not examined APOE by race interactions that are observed in HIV-negative older adults. Thus, we examined how APOE status relates to cognition and medial temporal lobe (MTL) structures (implicated in AD pathogenesis) in mid- to older-aged PWH. In exploratory analyses, we also examined race (African American (AA)/Black and non-Hispanic (NH) White) by APOE status interactions on cognition and MTL structures.
Participants and Methods:
The analysis included 88 PWH between the ages of 45 and 68 (mean age=51±5.9 years; 86% male; 51% AA/Black, 38% NH-White, 9% Hispanic/Latinx, 2% other) from the CNS HIV Antiretroviral Therapy Effects Research multi-site study. Participants underwent APOE genotyping, neuropsychological testing, and structural MRI; APOE groups were defined as APOE4+ (at least one APOE4 allele) and APOE4- (no APOE4 alleles). Eighty-nine percent of participants were on antiretroviral therapy, 74% had undetectable plasma HIV RNA (<50 copies/ml), and 25% were APOE4+ (32% AA/Black/15% NH-White). Neuropsychological testing assessed seven domains, and demographically-corrected T-scores were calculated. FreeSurfer 7.1.1 was used to measure MTL structures (hippocampal volume, entorhinal cortex thickness, and parahippocampal thickness) and the effect of scanner was regressed out prior to analyses. Multivariable linear regressions tested the association between APOE status and cognitive and imaging outcomes. Models examining cognition covaried for comorbid conditions and HIV disease characteristics related to global cognition (i.e., AIDS status, lifetime methamphetamine use disorder). Models examining the MTL covaried for age, sex, and
relevant imaging covariates (i.e., intracranial volume or mean cortical thickness).
Results:
APOE4+ carriers had worse learning (ß=-0.27, p=.01) and delayed recall (ß=-0.25, p=.02) compared to the APOE4- group, but APOE status was not significantly associated with any other domain (ps>0.24). APOE4+ status was also associated with thinner entorhinal cortex (ß=-0.24, p=.02). APOE status was not significantly associated with hippocampal volume (ß=-0.08, p=0.32) or parahippocampal thickness (ß=-0.18, p=.08). Lastly, race interacted with APOE status such that the negative association between APOE4+ status and cognition was stronger in NH-White PWH as compared to AA/Black PWH in learning, delayed recall, and verbal fluency (ps<0.05). There were no APOE by race interactions for any MTL structures (ps>0.10).
Conclusions:
Findings suggest that APOE4 carrier status is associated with worse episodic memory and thinner entorhinal cortex in mid- to older-aged PWH. While APOE4+ groups were small, we found that APOE4 carrier status had a larger association with cognition in NH-White PWH as compared to AA/Black PWH, consistent with studies demonstrating an attenuated effect of APOE4 in older AA/Black HIV-negative older adults. These findings further highlight the importance of recruiting diverse samples and suggest exploring other genetic markers (e.g., ABCA7) that may be more predictive of AD in some races to better understand AD risk in diverse groups of PWH.
Pediatric patients with frontal lobe epilepsy (FLE) have higher rates of attention deficit hyperactivity disorder (ADHD), as well as executive functioning (EF) and fine motor (FM) challenges. Relations between these constructs have been established in youth with ADHD and are supported by FM and EF skill involvement in frontal-subcortical systems. Still, they are not well understood in pediatric FLE. We hypothesized that poorer FM performance would be related to greater executive dysfunction and ADHD symptomatology in this group.
Participants and Methods:
47 children and adolescents with FLE (AgeM=12.47, SD=5.18; IQM=84.07; SD=17.56; Age of Seizure OnsetM=6.85, SD=4.64; right-handed: n=34; left-handed: n=10; Unclear: n=3) were enrolled in the Pediatric Epilepsy Research Consortium dataset as part of their phase I epilepsy surgical evaluation. Participants were selected if they had unifocal FLE and completed the Lafayette Grooved Pegboard (GP). Seizure lateralization (left-sided: n=19; right-sided: n=26; bilateral: n=2) and localization were established via data (e.g., EEG, MRI) presented at a multidisciplinary team case conference. Patients completed neuropsychological measures of FM, attention, and EF. Parents also completed questionnaires inquiring about their child’s everyday EF and ADHD symptomatology. Correlational analyses were conducted to examine FM, EF, and ADHD relations.
Results:
Dominant hand (DH) manual dexterity (GP) was related to parent-reported EF (Behavior Rating Inventory of Executive Function, Second Edition [BRIEF-2]-Global Executive Composite [GEC]: r(15) =-.70, p<.01, d=1.96). While not statistically significant, medium to large effect sizes were found for GP DH and parent-reported inattention (Behavior Assessment System for Children, Third Edition [BASC-3]-Attention Problems: r(12)=-.39, p=.17, d=.85) and hyperactivity/impulsivity (BASC-3-Hyperactivity: r(11)= -.44, p=.13, d=.98), as well as performance-based attention (Conners Continuous Performance Test, Third Edition -Omission Errors: r(12)=-.35, p=.22, d=.41), working memory (Wechsler Intelligence Scale for Children - Fifth Edition [WISC-V]-Digit Span [DS]: r(19)=.38, p=.09, d=.82) and cognitive flexibility (Delis-Kaplan Executive Function System (D-KEFS) Verbal Fluency Category Switching: r(13)=.46, p=.08, d=1.04); this suggests that these relations may exist but that our study was underpowered to detect them. Non-dominant hand (NDH) manual dexterity was related to performance-based working memory (WISC-V-DS: r(19)=.50, p<.01, d=1.12) and cognitive flexibility (D-KEFS-Trails Making Test Number-Letter Switching: r(17)=.64, p<.01, d=1.67). Again, while underpowered, medium to large effect sizes were found for GP NDH and parent-reported EF (BRIEF-2 GEC: r(15) =-.45, p=.07, d=1.01) and performance-based phonemic fluency (D-KEFS-Letter Fluency: r(13)=.31, p=.20, d=.65).
Conclusions:
Our findings suggest that FM, EF, and ADHD are related in youth with FLE; however, these relations appear to vary by skill and hand. We posit that our findings are due in part to the frontal-cerebellar networks given their anatomic proximity between frontal motor areas and the dorsolateral prefrontal cortex - as well as their shared functional involvement in these networks. Future studies should evaluate the predictive validity of initial FM skills for later executive dysfunction and ADHD symptomatology in FLE. If such relations emerge, contributions of early FM interventions on EF development should be examined. Further replication of these findings with a larger sample is warranted.
Rapid increase in the hectarage and agricultural systems that use cover cropping for soil conservation and improvement, soil moisture retention, and weed management has highlighted the need to develop formal breeding programs for cover crop species. Cereal rye (Secale cereale L.) is preferred by many growers due to high biomass production and weed-suppression potential, which is believed to be partially due to allelopathy. Rye germplasm exhibits large variability in allelopathic activity, which could be used to breed rye with enhanced weed suppression. Here, we provide an overview of rye history and breeding and describe a strategy to develop rye lines with increased allelopathic activity. The discussion focuses on ways to deal with important challenges to achieving this goal, including obligate cross-pollination and its consequent high segregation levels and the need to quantify allelopathic activity under field conditions. This review seeks to encourage weed scientists to collaborate with plant breeders and promote the development of cover crop cultivars better suited to reduce weed populations.