Objectives/Goals: The Standards for Reporting Implementation Studies (StaRI) are the Enhancing the Quality and Transparency of Health Research (EQUATOR) Network 27-item checklist for Implementation Science. This study quantifies StaRI adherence among self-defined Implementation Science studies in published Learning Health Systems (LHS) research. Methods/Study Population: A medical librarian-designed a search strategy identified original Implementation Science research published in one of the top 20 Implementation Science journals between 2017 and 2021. Inclusion criteria included studies or protocols describing the implementation of any intervention in healthcare settings. Exclusion criteria included concept papers, non-implementation research, or editorials. Full-text documents were reviewed by two investigators to abstract and judge StaRI implementation and intervention adherence, partial adherence, or non-adherence. Results/Anticipated Results: A total of 330 documents were screened, 97 met inclusion criteria, and 47 were abstracted including 30 research studies and 17 protocols. Adherence to individual StaRI reporting items ranged from 13% to 100%. Most StaRI items were reported in >60% of manuscripts and protocols. The lowest adherence in research studies was noted around economic evaluation reporting for implementation (16%) or intervention (13%) strategies, harms (13%), contextual changes (30%), or fidelity of either the intervention (34%) or implementation (53%) approach. Subgroup analyses were infrequently contemplated or reported (43%). In protocols, the implications of the implementation strategy (41%) or intervention approach (47%) were not commonly reported. Discussion/Significance of Impact: When leveraging implementation science to report reproducible and sustainable practice change initiatives, LHS researchers will need to include assessments of economics, harms, context, and fidelity in order to attain higher levels of adherence to EQUATOR’s StaRI checklist.

OBJECTIVES/SPECIFIC AIMS: Treatment of acute myeloid leukemia (AML) is challenging, as apoptosis-resistant AML cells often persist within the bone marrow microenvironment despite chemotherapy. The overall goal of our laboratory is to identify and ultimately target the bone marrow factors that protect AML cells. METHODS/STUDY POPULATION: Using cell cultures, we previously reported that SDF-1 (CXCL12), an abundant bone marrow chemokine, induces apoptosis of isolated CXCR4+ AML cells, including freshly isolated bone marrow-derived AML cells from approximately one-third of AML patients. However, co-culture of AML cells with differentiating osteoblasts protected AML cells from apoptosis. RESULTS/ANTICIPATED RESULTS: Histone deacetylase inhibitors (HDACi) abrogated the ability of osteoblasts to protect AML cells and altered expression of matrix mineralization genes including tissue nonspecific alkaline phosphatase (TNAP). A different drug, cyclosporine A (CSA), similarly inhibited osteoblast-mediated protection of AML cells and reduced TNAP expression. Specifically targeting osteoblast TNAP via siRNA was sufficient to prevent osteoblasts from protecting AML cells in co-cultures. In addition, we are targeting TNAP enzymatically. DISCUSSION/SIGNIFICANCE OF IMPACT: Our results indicate that targeting TNAP may be useful in AML treatment to render the bone marrow microenvironment more hostile to leukemic cell survival.

Velvetleaf (Abutilon theophrasti Medik. # ABUTH) seeds were bioassayed on 241 microbial isolates to assess their antimicrobial activity. Seeds placed on agar plates inoculated with test microorganisms released a diffusible substance(s) that inhibited the growth of 117 of 202 (58%) bacteria and all of the fungi tested. Antimicrobial activity of the seeds appeared to be nonselective as the extent of inhibition was not related to type of microorganism nor their origin. Hard, water-impermeable seeds had greater inhibitory activity than imbibed (soft) seeds. The intensity of inhibition was affected by prior leaching of seeds with various solvents and by the stage of seed development. Chemical analysis of diffusion zones from agar plates and seed leachates revealed the presence of phenolic compounds. The presence of antimicrobial substances in velvetleaf seeds may contribute to the persistence of viable seeds in soil by inhibiting potential seed-deteriorating microorganisms.

Rhizobacteria have been shown to be phytotoxic to leafy spurge in laboratory assays. This field study investigated the influence of two strains of Pseudomonas fluorescens [Trevisan, (Migula)], deleterious rhizobacteria (DRB), on root weight, root bud number, and root carbohydrate content of leafy spurge at three sites located in northeast and north-central South Dakota. Soils were inoculated with 2 g of starch-based granules containing no bacteria or starch granules containing 108colony-forming units (cfu)/g of either bacterial strain LS102 (Montana origin) or LS174 (South Dakota origin). Bacterial strains were detected on root samples from treated areas. Root weight and root carbohydrate content were reduced about 20% compared to roots from control plots.

The relationships between microorganisms and velvetleaf (Abutilon theophrasti Medic. # ABUTH) seeds in contact with soil were studied to determine microbial effects on velvetleaf seed viability. The characteristic seed microbial association persisted on velvetleaf seeds placed on the soil surface during 32 days of incubation. The fungal association comprised of Alternaria alternata (Fr.) Keissl., Cladosporium cladosporioides (Fres.) de Vries, Epicoccum purpurascens Ehrenb. ex Schlecht, and Fusarium spp. was detected on over 50% of the seeds during incubation. Establishment of soil microorganisms on 50% of seeds occurred at only one sampling date. Such establishment was largely unsuccessful due to the effective barrier presented by seedborne microorganisms. Seedborne and soilborne microorganisms were unable to reduce viability of velvetleaf seeds in contact with soil as the total viability of all seeds tested exceeded 90% during incubation. Velvetleaf seedborne microorganisms may augment seed longevity on and in soils by acting as a barrier to potential seed decomposers originating from soil.

Germination stimulants were tested for effectiveness on velvetleaf seed imbibition and germination and concurrent microbial attack of seed to deplete weed seed in soil. Several chemicals increased in vitro seed germination and decreased the numbers of hard, viable seed. The proportion of nonviable seed, 5% with Fusarium oxysporum (Schlech.), was enhanced to 40% by adding ethephon at 100 μg/ml. Fungal density on seedling roots and imbibed (nonviable seed) was increased by chemical treatment. Seedling emergence was reduced 15% when ethephon or carbofuran was applied to soil with the fungus. Shoot dry weight decreased and root infection increased with all treatments regardless of fungal inoculation. Butylate and carbofuran increased infection of imbibed seed in soil by F. oxysporum while ethephon and AC94377 increased infection by other soil fungi.

A scentless plant bug feeds on velvetleaf seeds. Fungi, dominated by the genera Fusarium and Alternaria, were isolated from insect-attacked seeds at levels related to insect density on the plants. The combined effects of insect feeding and fungal infection decreased seed germination. Burial of insect-attacked seeds in soil for 24 months reduced seed survival and increased Fusarium infection. Decreases in velvetleaf seed viability and survival in soil caused by a seed-feeding insect and associated seed fungi suggests that subsequent infestations by velvetleaf can be decreased through integrated use of the two biological control agents.

Field experiments, conducted from 1991 to 1994, generated information on weed seedbank emergence for 22 site-years from Ohio to Colorado and Minnesota to Missouri. Early spring seedbank densities were estimated through direct extraction of viable seeds from soil cores. Emerged seedlings were recorded periodically, as were daily values for air and soil temperature, and precipitation. Percentages of weed seedbanks that emerged as seedlings were calculated from seedbank and seedling data for each species, and relationships between seedbank emergence and microclimatic variables were sought. Fifteen species were found in 3 or more site-years. Average emergence percentages (and coefficients of variation) of these species were as follows: giant foxtail, 31.2 (84%); velvetleaf, 28.2 (66); kochia, 25.7 (79); Pennsylvania smartweed, 25.1 (65); common purslane, 15.4 (135); common ragweed, 15.0 (110); green foxtail, 8.5 (72); wild proso millet, 6.6 (104); hairy nightshade, 5.2 (62); common sunflower, 5.0 (26); yellow foxtail, 3.4 (67); pigweed species, 3.3 (103); common lambsquarters, 2.7 (111); wild buckwheat, 2.5 (63), and prostrate knotweed, 0.6 (79). Variation among site-years, for some species, could be attributed to microclimate variables thought to induce secondary dormancy in spring. For example, total seasonal emergence percentage of giant foxtail was related positively to the 1st date at which average daily soil temperature at 5 to 10 cm soil depth reached 16 C. Thus, if soil warmed before mid April, secondary dormancy was induced and few seedlings emerged, whereas many seedlings emerged if soil remained cool until June.

Bioassays using cell cultures and callus tissues of leafy spurge were devised to evaluate the potential of rhizobacteria as biocontrol agents. Rhizobacteria isolated from roots of leafy spurge seedlings were screened in suspension-cultured leafy spurge cells. Cell viability was assessed using the Evan's blue bioassay 48 h after bacterial inoculation. Among the 30 isolates tested, LS102 and LS105 consistently caused intensive cell death determined by measuring the A630 of the inoculated cell cultures. Cell death was 2.5 to 3 times higher in cultures inoculated with LS105 and LS102, respectively, than in the control. Population levels of the two isolates within cell cultures and callus tissues of leafy spurge increased during the first 48 h. Leafy spurge callus tissues were inoculated with rhizobacteria either directly or by using the Host Pathogen Interaction System (HPIS). The latter exposes calli to bacteria without any physical contact. LS102 caused cellular leakage and eventually death of the callus tissue. Callus growth was reduced by about 30 to 70% when exposed to LS102 and LS105, respectively. Results suggest that these two isolates may affect leafy spurge at the cellular level by different mechanisms. A screening method based on cell cultures and callus tissues offers a good and rapid technique for detecting deleterious rhizobacteria with potential as biocontrol agents for leafy spurge.

Field infestations of a seed-feeding insect developed from overwintered populations reduced viability of velvetleaf seed to 17.5 and 15.5% at two locations in central Missouri, compared to 95.5 and 87.5% at insect-free sites. Insect feeding enhanced the proportion of seedborne microorganisms in seed up to 98% compared to the average fungal infection of 8% for seed not exposed to the insect. There was a strong negative correlation between fungal infection associated with insect feeding and percent velvetleaf seed viability. The insect transmits microorganisms externally just as pollen is carried by various other insect species and not by ingestion and regurgitation. The effectiveness of the insect on reducing seed viability and seed production in central Missouri is mainly limited by the time required to build up populations capable of significantly affecting early-season velvetleaf seed production.

There is a current need to develop alternative weed management techniques in response to demands for reduction in herbicide use due mainly to health and environmental concerns. Therefore, all possible nonchemical strategies for weed control should be considered, including biological control. Deleterious rhizobacteria (DRB), largely overlooked as potential biological control agents for weeds until recently, are able to colonize root surfaces of weed seedlings and suppress plant growth. Limited field studies indicate that DRB suppressed weed growth, and reduced weed density, biomass, and seed production. In this manner, crops out-compete the suppressed weeds for growth requirements, eliminating the necessity for eradication of weeds in the crop. Establishment of DRB as a viable biological control strategy initially will require integration with other weed control approaches including other biocontrol agents, agrichemicals, and cultural and residue management practices. To achieve success, more in-depth research is needed on ecology of bacteria-plant relationships, mechanisms of action (including characterization of phytotoxins), inocula formulations, and methods to enhance crop competition.

Soil microbial community structure and activity are linked to plantcommunities. Weeds may alter their soil environment, selecting for specificrhizosphere microbial communities. Rhizosphere modification occurs for manycrop and horticultural plants. However, impacts of weeds in agroecosystemson soil biology and ecology have received less attention because effectiveweed management practices were developed to minimize their impacts on cropproduction. The recent development of herbicide resistance (HR) in severaleconomically important weeds leading to widespread infestations in cropfields treated with a single herbicide has prompted a re-evaluation of theeffects of weed growth on soil biology and ecology. The objective of thisarticle is to review the potential impacts of herbicide-resistant weeds onsoil biological and ecological properties based on reports for crops, weeds,and invasive plants. Persistent weed infestations likely establish extensiveroot systems and release various plant metabolites through root exudation.Many exudates are selective for specific soil microbial groups mediatingbiochemical and nutrient acquisition processes. Exudates may stimulatedevelopment of microbial groups beneficial to weed but detrimental to cropgrowth or beneficial to both. Changes in symbiotic and associative microbialinteractions occur, especially for arbuscular mycorrhizal fungi (AMF) thatare important in plant uptake of nutrients and water, and protecting fromphytopathogens. Mechanisms used by weeds to disrupt symbioses in crops arenot clearly described. Many herbicide-resistant weeds including Amaranthus and Chenopodium do notsupport AMF symbioses, potentially reducing AMF propagule density andestablishment with crop plants. Herbicides applied to control HR weeds maycompound effects of weeds on soil microorganisms. Systemic herbicidesreleased through weed roots may select microbial groups that mediatedetrimental processes such as nutrient immobilization or serve asopportunistic pathogens. Understanding complex interactions of weeds withsoil microorganisms under extensive infestations is important in developingeffective management of herbicide-resistant weeds.

Field studies were conducted to determine the effect of early-season and early- plus late-season acetolactate synthase–resistant Helianthus annuus interference on Glycine max and H. annuus growth and yield at two sites in Missouri. Helianthus annuus densities of 3 plants m−2 were established shortly after G. max emergence in all plots except the weed-free check. To study early-season interference, H. annuus were removed with postemergence glyphosate (0.84 kg ae ha−1) 2, 4, 6, and 8 wk after planting (WAP) and kept weed-free for the rest of the growing season. Glycine max yields were not different with 2, 4, 6, or 8 wk of early-season interference at either location. To study early- plus late-season interference, H. annuus densities were established at 3 plants m−2. They were then removed 2, 4, 6, or 8 WAP with glyphosate and subsequently reestablished at the same density within 2 wk after removal by newly emerging and transplanted H. annuus. These H. annuus were allowed to remain in the field for the remainder of the growing season. This provided a weed-free period of approximately 2 wk during the growing season beginning 2, 4, 6, or 8 WAP. Season-long interference and no-interference treatments were also included. Glycine max yields were reduced 47 to 72% with season-long interference. Helianthus annuus vegetative dry matter was approximately 56% lower at Columbia than at Miami. Glycine max yields tended to increase as the weed-free period was delayed into the growing season. Early-season weed-free periods (2 to 4 and 4 to 6 WAP) allowed H. annuus to become re-established before G. max formed a canopy and resulted in larger amounts of H. annuus biomass and seed production as well as G. max yield losses of 15 to 80%. Re-establishment of H. annuus in 6 to 8 WAP and 8 to 10 WAP weed-free treatments generally resulted in the plants surviving for only a few weeks after establishment and not producing seed or reducing G. max yield.