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Paskewitz, S.

Publications and source records attributed to Paskewitz, S..

4 recordsLinked to original sources

Integrating multi-system environmental factors to predict brain and behavior in adolescents

ObjectiveEnvironmental factors have long been shown to influence brain structure and adolescent psychopathology. However, almost no research has included environmental factors spanning micro-to-macro-systems, brain structure, and psychopathology in an integrated framework. Here, we assessed the ways and degree to which multi-system environmental factors during late childhood predict subcortical volume and psychopathology during early adolescence. MethodWe used the baseline and 2-year follow-up data from the Adolescent Brain Cognitive DevelopmentSM Study (N = 2,766). A Bayesian latent profile analysis was applied to obtain distinct multi-system environmental profiles during late childhood. The profiles were used in a path analysis to predict their direct and indirect effects on subcortical volume and psychopathology during early adolescence. ResultsBayesian latent profile analysis revealed nine environmental profiles. Two distinct profiles predicted greater externalizing problems in adolescents: (i) adversity across, family, school, and neighborhood systems and (ii) family conflict and low school involvement. In contrast, a profile of family and neighborhood affluence predicted fewer externalizing difficulties. Further, family and neighborhood affluence predicted higher subcortical volume, which in turn, predicted fewer externalizing problems; whereas, family economic and neighborhood adversity predicted lower subcortical volume, which in turn, predicted greater externalizing difficulties. ConclusionWe captured direct and indirect influences of environmental factors across multiple systems on externalizing psychopathology. Specifying the equifinal pathways to externalizing psychopathology serves to provide an evidence base for establishing different types of interventions based on the needs and risk profiles of youth. Diversity and Inclusion StatementThe current study is part of the ongoing Adolescent Brain Cognitive DevelopmentSM Study (ABCD Study(R)) for which youth are recruited from elementary schools in the United States that are informed by gender, race, ethnicity, socioeconomic status, and urbanicity. The ABCD Study(R) aims to recruit youth longitudinally by sampling the sociodemographic makeup of the US population. Two of the authors self-identifies as a member of one or more historically underrepresented racial and/or ethnic groups in science. One of the authors identifies as a part of an underrepresented gender group in science. The authors also are representative of the communities for which data was collected and contributed to design, analysis, and/or interpretation of the work. Finally, every effort was made to cite the work of authors from underrepresented and minoritized groups in academic research.

neuroscience↗

Bacteria: A novel source for potent mosquito feeding-deterrents

Antibiotic and insecticidal bioactivities of the extracellular secondary metabolites produced by entomopathogenic bacteria belonging to genus Xenorhabdus have been identified; however, their novel applications such as mosquito feeding-deterrence have not been reported. Here, we show that a mixture of compounds isolated from Xenorhabdus budapestensis in vitro cultures exhibits potent feeding-deterrent activity against three deadly mosquito vectors: Aedes aegypti, Anopheles gambiae and Culex pipiens. We further demonstrate that the deterrent-active fraction isolated from replicate bacterial cultures is consistently highly enriched in two modified peptides identical to the previously described fabclavines, strongly suggesting that these are molecular species responsible for feeding-deterrence. The mosquito feeding-deterrent activity in the fabclavines-rich fraction is comparable to or better than that of N, N-diethyl-3-methylbenzamide (also known as Deet) or picaridin in side-by-side assays. Our unique discovery lays the groundwork for research into biologically derived, peptide-based low molecular weight compounds isolated from bacteria for exploitation as mosquito repellents and feeding-deterrents.

microbiology↗

Ixodes scapularis does not harbor a stable midgut microbiome

Hard ticks of the order Ixodidae serve as vectors for numerous human pathogens, including the causative agent of Lyme Disease Borrelia burgdorferi. Tick-associated microbes can influence pathogen colonization, offering the potential to inhibit disease transmission through engineering of the tick microbiota. Here, we investigate whether B. burgdorferi encounters abundant bacteria within the midgut of wild adult Ixodes scapularis, its primary vector. Through the use of controlled sequencing methods and confocal microscopy, we find that the majority of field-collected adult I. scapularis harbor limited internal microbial communities that are dominated by endosymbionts. A minority of I. scapularis ticks harbor abundant midgut bacteria and lack B. burgdorferi. We find that the lack of a stable resident midgut microbiota is not restricted to I. scapularis since extension of our studies to I. pacificus, Amblyomma maculatum, and Dermacentor spp showed similar patterns. Finally, bioinformatic examination of the B. burgdorferi genome revealed the absence of genes encoding known interbacterial interaction pathways, a feature unique to the Borrelia genus within the phylum Spirochaetes. Our results suggest that reduced selective pressure from limited microbial populations within ticks may have facilitated the evolutionary loss of genes encoding interbacterial competition pathways from Borrelia.

microbiology↗