Application of a Heuristic Framework for Multilevel Interventions to Eliminate the Impact of Unjust Social Processes and Other Harmful Social Determinants of Health.

There is consensus about the importance of developing a strong cadre of effective multilevel interventions to eliminate the impacts of unjust social processes, such as structural racism and other harmful social determinants of health (SDOH), on health inequities in the USA. However, the available cadre of rigorously evaluated evidence-based interventions for SDOH mitigation remains underdeveloped relative to the magnitude of historic and current health inequities. The proposed manuscript addresses this gap in two ways: first, by introducing a heuristic framework to inform decisions in multilevel intervention development, study design, and selection of analytic methods and, second, by providing a roadmap for future applications of the framework in multilevel intervention research through an exemplar application using the ongoing NIH-funded evaluation study of the Nurse-Community-Family Partnership (NCFP) intervention. NCFP leverages individual, family, institutional, and system factors to shape COVID-19 mitigation outcomes at the individual and household levels. NCFP takes an approach informed by the heuristic framework to addressing and mitigating unjust social processes and other harmful SDOH. We discuss the application of a two-arm parallel explanatory group randomized trial to evaluate the efficacy of NCFP in improving the primary (COVID-19 testing uptake) and secondary (adoption of COVID-19 control measures, COVID-19 vaccine uptake, mutual aid capacity, etc.) outcomes at the individual and household levels. The analysis approach relies on random-intercept models, and we calculate the variance partitioning coefficient to estimate the extent to which household- and individual-level variables contribute to the outcome, allowing examination of NCFP effects at multiple levels.

Novel insights into the role of long non-coding RNA in the human malaria parasite, Plasmodium falciparum.

The complex life cycle of Plasmodium falciparum requires coordinated gene expression regulation to allow host cell invasion, transmission, and immune evasion. Increasing evidence now suggests a major role for epigenetic mechanisms in gene expression in the parasite. In eukaryotes, many lncRNAs have been identified to be pivotal regulators of genome structure and gene expression. To investigate the regulatory roles of lncRNAs in P. falciparum we explore the intergenic lncRNA distribution in nuclear and cytoplasmic subcellular locations. Using nascent RNA expression profiles, we identify a total of 1768 lncRNAs, of which 718 (~41%) are novels in P. falciparum. The subcellular localization and stage-specific expression of several putative lncRNAs are validated using RNA-FISH. Additionally, the genome-wide occupancy of several candidate nuclear lncRNAs is explored using ChIRP. The results reveal that lncRNA occupancy sites are focal and sequence-specific with a particular enrichment for several parasite-specific gene families, including those involved in pathogenesis and sexual differentiation. Genomic and phenotypic analysis of one specific lncRNA demonstrate its importance in sexual differentiation and reproduction. Our findings bring a new level of insight into the role of lncRNAs in pathogenicity, gene regulation and sexual differentiation, opening new avenues for targeted therapeutic strategies against the deadly malaria parasite.

Small RNA sequencing of field Culex mosquitoes identifies patterns of viral infection and the mosquito immune response.

Mosquito-borne disease remains a significant burden on global health. In the United States, the major threat posed by mosquitoes is transmission of arboviruses, including West Nile virus by mosquitoes of the Culex genus. Virus metagenomic analysis of mosquito small RNA using deep sequencing and advanced bioinformatic tools enables the rapid detection of viruses and other infecting organisms, both pathogenic and non-pathogenic to humans, without any precedent knowledge. In this study, we sequenced small RNA samples from over 60 pools of Culex mosquitoes from two major areas of Southern California from 2017 to 2019 to elucidate the virome and immune responses of Culex. Our results demonstrated that small RNAs not only allowed the detection of viruses but also revealed distinct patterns of viral infection based on location, Culex species, and time. We also identified miRNAs that are most likely involved in Culex immune responses to viruses and Wolbachia bacteria, and show the utility of using small RNA to detect antiviral immune pathways including piRNAs against some pathogens. Collectively, these findings show that deep sequencing of small RNA can be used for virus discovery and surveillance. One could also conceive that such work could be accomplished in various locations across the world and over time to better understand patterns of mosquito infection and immune response to many vector-borne diseases in field samples.

Plasmodium kinesin-8X associates with mitotic spindles and is essential for oocyst development during parasite proliferation and transmission.

Kinesin-8 proteins are microtubule motors that are often involved in regulation of mitotic spindle length and chromosome alignment. They move towards the plus ends of spindle microtubules and regulate the dynamics of these ends due, at least in some species, to their microtubule depolymerization activity. Plasmodium spp. exhibit an atypical endomitotic cell division in which chromosome condensation and spindle dynamics in the different proliferative stages are not well understood. Genome-wide shared orthology analysis of Plasmodium spp. revealed the presence of two kinesin-8 motor proteins, kinesin-8X and kinesin-8B. Here we studied the biochemical properties of kinesin-8X and its role in parasite proliferation. In vitro, kinesin-8X has motility and depolymerization activities like other kinesin-8 motors. To understand the role of Plasmodium kinesin-8X in cell division, we used fluorescence-tagging and live cell imaging to define its location, and gene targeting to analyse its function, during all proliferative stages of the rodent malaria parasite P. berghei life cycle. The results revealed a spatio-temporal involvement of kinesin-8X in spindle dynamics and an association with both mitotic and meiotic spindles and the putative microtubule organising centre (MTOC). Deletion of the kinesin-8X gene revealed a defect in oocyst development, confirmed by ultrastructural studies, suggesting that this protein is required for oocyst development and sporogony. Transcriptome analysis of Δkinesin-8X gametocytes revealed modulated expression of genes involved mainly in microtubule-based processes, chromosome organisation and the regulation of gene expression, supporting a role for kinesin-8X in cell division. Kinesin-8X is thus required for parasite proliferation within the mosquito and for transmission to the vertebrate host.

Quantitative Analysis of Photobodies.

Photobodies are membraneless subnuclear organelles that contain the red and far-red photoreceptors, phytochromes. Photobody biogenesis has been postulated to play important roles in early light signaling events. The size and number of photobodies are highly dynamic in response to the quality and quantity of light and correlated tightly with phytochrome-mediated seedling morphogenesis. Here, we provide a detailed protocol for characterization of the three-dimensional morphology of photobodies, including sample preparation, fluorescence microscopy, and image analysis. Although this method was developed initially for characterizing photobodies, it can be adopted to analyze other membraneless or membrane-bound subcellular organelles.

The effect of race and birth cohort on the veteran mortality differential.

Research on veteran versus nonveteran mortality outcomes provides contrary results, with some studies reporting a veteran mortality advantage while others report a veteran mortality disadvantage. Life course scholars suggest these conflicting results may be explained by a crossover in the veteran-nonveteran mortality differential, with veterans having a mortality advantage during early and midlife and a mortality disadvantage during older age. We conducted discrete time hazard analysis of a veteran-nonveteran mortality crossover among black and white men in the United States by birth cohort using data from the 1986-2009(2011) National Health Interview Survey-Linked Mortality Files. Among men who turned age 18 during non-war eras, veterans had an early to midlife mortality advantage and later life mortality disadvantage, with differences more pronounced among black men. However, differences between veteran and nonveteran mortality risk were not significant among the majority of men who turned age 18 during war eras. Findings clarify that the mortality related benefits of military service may only apply to veterans who came of age during non-war eras. Furthermore, results suggest that military service may provide a greater mortality benefit to black veterans than white veterans.