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Abstract Bone is a hierarchical material formed by an organic extracellular matrix and mineral where each component and their physical relationship with each other contribute to fracture resistance. Bone quality can be affected by nutrition, and dietary supplements that are marketed to improve overall health may improve the fracture resistance of bone. To test this, 11 week old female C57BL/6 mice were fed either collagen, chondroitin sulfate, glucosamine sulfate, or fish oil 5 times a week for 8 weeks. Femurs, tibiae, and vertebrae were scanned with micro-computed tomography and then mechanically tested. Glucosamine and fish oil lowered elastic modulus, but did not alter the overall strength of the femur. There were no differences in bone mechanics of the tibiae or vertebrae. Overall, the data suggest that dietary supplements did little to improve bone quality in young, healthy mice. These supplements may be more effective in diseased or aged mice.

Persons with HIV-associated Kaposi's sarcoma (KS) experience three co-existing stigmatizing health conditions: skin disease, HIV, and cancer, which contribute to a complex experience of stigmatization and to delays in diagnosis and treatment. Despite the importance of stigma among these patients, there are few proven stigma-reduction strategies for HIV-associated malignancies. Using qualitative methods, we explore how people with HIV-associated KS in western Kenya between August 2022 and 2023 describe changes in their stigma experience after participation in a multicomponent navigation strategy, which included 1) physical navigation and care coordination, 2) video-based education with motivational survivor stories, 3) travel stipend, 4) health insurance enrollment assistance, 5) health insurance stipend, and 6) peer mentorship. A purposive sample of persons at different stages of chemotherapy treatment were invited to participate. Participants described how a multicomponent navigation strategy contributed to increased knowledge and awareness, a sense of belonging, hope to survive, encouragement, and social support, which served as stigma mitigators, likely counteracting the major drivers of intersectional stigma in HIV-associated KS., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Competing Interests: Conflicts of interest None disclosed.

Background: Implementation science has been recognized for its potential to improve the integration of evidence-based practices into routine dermatologic care. The COVID-19 pandemic has resulted in rapid teledermatology implementation worldwide. Although several studies have highlighted patient and care provider satisfaction with teledermatology during the COVID-19 pandemic, less is known about the implementation process., Objective: Our goal was to use validated tools from implementation science to develop a deeper understanding of the implementation of teledermatology during the COVID-19 pandemic. Our primary aims were to describe (1) the acceptability and feasibility of the implementation of teledermatology and (2) organizational readiness for the implementation of teledermatology during the COVID-19 pandemic. We also sought to offer an example of how implementation science can be used in dermatologic research., Methods: An anonymous, web-based survey was distributed to Association of Professors of Dermatology members. It focused on (1) the acceptability, feasibility, and appropriateness of teledermatology and (2) organizational readiness for implementing teledermatology. It incorporated subscales from the Organizational Readiness to Change Assessment-a validated measure of organizational characteristics that predict implementation success., Results: Of the 518 dermatologists emailed, 35 (7%) responded, and all implemented or scaled up teledermatology during the pandemic. Of the 11 care providers with the highest level of organizational readiness, 11 (100%) said that they plan to continue using teledermatology after the pandemic. Most respondents agreed or strongly agreed that they had sufficient training (24/35, 69%), financial resources (20/35, 57%), and facilities (20/35, 57%). However, of the 35 respondents, only 15 (43%) agreed or strongly agreed that they had adequate staffing support. Most respondents considered the most acceptable teledermatology modality to be synchronous audio and video visits with supplemental stored digital photos (23/35, 66%) and considered the least acceptable modality to be telephone visits without stored digital photos (6/35, 17%). Overall, most respondents thought that the implementation of synchronous audio and video with stored digital photos (31/35, 89%) and telephone visits with stored digital photos (31/35, 89%) were the most feasible. When asked about types of visits that were acceptable for synchronous video/audio visits (with stored digital photos), 18 of the 31 respondents (58%) said "new patients," 27 (87%) said "existing patients," 19 (61%) said "medication monitoring," 3 (10%) said "total body skin exams," and 22 (71%) said "lesions of concern.", Conclusions: This study serves as an introduction to how implementation science research methods can be used to understand the implementation of novel technologies in dermatology. Our work builds upon prior studies by further characterizing the acceptability and feasibility of different teledermatology modalities. Our study may suggest initial insights on how dermatology practices and health care systems can support dermatologists in successfully incorporating teledermatology after the pandemic., Competing Interests: Conflicts of Interest: None declared., (©Shanelle Mariah Briggs, Jules Benjamin Lipoff, Sigrid Marie Collier. Originally published in JMIR Dermatology (http://derma.jmir.org), 09.06.2022.)

Purpose of Review: Summarize the current evidence for teledermatology in rural, underserved, and isolated environments including its use during the current COVID-19 pandemic., Recent Findings: Teledermatology is a reliable and cost-effective tool that can reduce face-to-face visits and improve the timeliness of care for medically underserved populations. Recent studies have shown many additional benefits of teledermatology, including improving patients' health outcomes and increasing local providers' knowledge of dermatologic conditions. Despite these benefits, many low-income and rural populations lack access to digital technology and high-speed internet, limiting the reach of telemedical services., Summary: Overall, barriers in access to care are unique across the globe, and thus teledermatology interventions should address and adapt to the needs of the local patient population. Certain strategies, such as implementing simple, SF models, using standardized TD consult templets, and providing real-time information technology support could potentially mitigate disparities and improve the effectiveness of TD programs in underserved areas., Competing Interests: Conflicts of InterestThe authors declare no competing interests., (© This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2022.)

Background: The coronavirus disease 2019 (COVID-19) pandemic profoundly affected food systems including food security. Understanding how the COVID-19 pandemic impacted food security is important to provide support and identify long-term impacts and needs., Objective: The National Food Access and COVID research Team (NFACT) was formed to assess food security over different US study sites throughout the pandemic, using common instruments and measurements. This study presents results from 18 study sites across 15 states and nationally over the first year of the COVID-19 pandemic., Methods: A validated survey instrument was developed and implemented in whole or part through an online survey of adults across the sites throughout the first year of the pandemic, representing 22 separate surveys. Sampling methods for each study site were convenience, representative, or high-risk targeted. Food security was measured using the USDA 6-item module. Food security prevalence was analyzed using ANOVA by sampling method to assess statistically significant differences., Results: Respondents ( n  = 27,168) indicate higher prevalence of food insecurity (low or very low food security) since the COVID-19 pandemic, compared with before the pandemic. In nearly all study sites, there is a higher prevalence of food insecurity among Black, Indigenous, and People of Color (BIPOC), households with children, and those with job disruptions. The findings demonstrate lingering food insecurity, with high prevalence over time in sites with repeat cross-sectional surveys. There are no statistically significant differences between convenience and representative surveys, but a statistically higher prevalence of food insecurity among high-risk compared with convenience surveys., Conclusions: This comprehensive study demonstrates a higher prevalence of food insecurity in the first year of the COVID-19 pandemic. These impacts were prevalent for certain demographic groups, and most pronounced for surveys targeting high-risk populations. Results especially document the continued high levels of food insecurity, as well as the variability in estimates due to the survey implementation method., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.)

One of the most widespread approaches for measurement of greenhouse gas emissions from soils involves the use of static chambers. This method is relatively inexpensive, is easily replicated, and is ideally suited to plot-based experimental systems. Among its limitations is the loss of detection sensitivity with increasing chamber height, which creates challenges for deployment in systems including tall vegetation. It is not always possible to avoid inclusion of plants within chambers or to extend chamber height to fully accommodate plant growth. Thus, in many systems, such as perennial forages and biomass crops, plants growing within static chambers must either be trimmed or folded during lid closure. Currently, data on how different types of biomass manipulation affect measured results is limited. Here, we compare the effects of cutting vs. folding of biomass on nitrous oxide measurements in switchgrass ( L.) and alfalfa ( L.) systems. We report only limited evidence of treatment effects during discrete sampling events and little basis for concern that effects may intensify over time as biomass manipulation is repeatedly imposed. However, nonsignificant treatment effects that were consistently present amounted to significant overall trends in three out of the four systems studied. Such minor disparities in flux could amount to considerable quantities over time, suggesting that caution should be exercised when comparing cumulative emission values from studies using different biomass manipulation strategies., (Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.)

Measurement of greenhouse gas (GHG) fluxes between the soil and the atmosphere, in both managed and unmanaged ecosystems, is critical to understanding the biogeochemical drivers of climate change and to the development and evaluation of GHG mitigation strategies based on modulation of landscape management practices. The static chamber-based method described here is based on trapping gases emitted from the soil surface within a chamber and collecting samples from the chamber headspace at regular intervals for analysis by gas chromatography. Change in gas concentration over time is used to calculate flux. This method can be utilized to measure landscape-based flux of carbon dioxide, nitrous oxide, and methane, and to estimate differences between treatments or explore system dynamics over seasons or years. Infrastructure requirements are modest, but a comprehensive experimental design is essential. This method is easily deployed in the field, conforms to established guidelines, and produces data suitable to large-scale GHG emissions studies.

The potato (Solanum tuberosum) disease resistance protein Rx has a modular arrangement that contains coiled-coil (CC), nucleotide-binding (NB), and leucine-rich repeat (LRR) domains and mediates resistance to potato virus X. The Rx N-terminal CC domain undergoes an intramolecular interaction with the Rx NB-LRR region and an intermolecular interaction with the Rx cofactor RanGAP2 (Ran GTPase-activating protein 2). Here, we report the crystal structure of the Rx CC domain in complex with the Trp-Pro-Pro (WPP) domain of RanGAP2. The structure reveals that the Rx CC domain forms a heterodimer with RanGAP2, in striking contrast to the homodimeric structure of the CC domain of the barley disease resistance protein MLA10. Structure-based mutagenesis identified residues from both the Rx CC domain and the RanGAP2 WPP domain that are crucial for their interaction and function in vitro and in vivo. Our results reveal the molecular mechanism underlying the interaction of Rx with RanGAP2 and identify the distinct surfaces of the Rx CC domain that are involved in intramolecular and intermolecular interactions.

Plant genomes encode large numbers of nucleotide-binding, leucine-rich repeat (NB-LRR) proteins, many of which are active in pathogen detection and defense response induction. NB-LRR proteins fall into two broad classes: those with a Toll and interleukin-1 receptor (TIR) domain at their N-terminus and those with a coiled-coil (CC) domain at the N-terminus. Within CC-NB-LRR-encoding genes, one basal clade is distinguished by having CC domains resembling the Arabidopsis thaliana RPW8 protein, which we refer to as CCR domains. Here, we show that CCR-NB-LRR-encoding genes are present in the genomes of all higher plants surveyed, and that they comprise two distinct subgroups: one typified by the Nicotiana benthamiana N-required gene 1 (NRG1) protein and the other typified by the Arabidopsis activated disease resistance gene 1 (ADR1) protein. We further report that, in contrast to CC-NB-LRR proteins, the CCR domains of both NRG1- and ADR1-like proteins are sufficient for the induction of defense responses, and that this activity appears to be SGT1-independent. Additionally, we report the apparent absence of both NRG1 homologs and TIR-NB-LRR-encoding genes from the dicot Aquilegia coerulea and the dicotyledonous order Lamiales as well as from monocotyledonous species. This strong correlation in occurrence is suggestive of a functional relationship between these two classes of NB-LRR proteins.

Plant genomes encode large numbers of highly variable nucleotide binding leucine-rich repeat (NB-LRR) disease resistance proteins. These proteins have been studied extensively to understand their evolution and the molecular basis of their function. Multiple studies indicate that the C-terminal LRR domain plays a pivotal role in defining pathogen recognition specificity. However, a growing body of evidence suggests that the N-termini of NB-LRR proteins also function in pathogen recognition. To formulate a framework that can explain the underlying principles governing NB-LRR function while accommodating findings from different experimental systems, we present a "bait and switch" model. This model proposes a two-step recognition process involving interactions with both cellular cofactors (bait) and the LRR domain, which in turn activates the molecular switch leading to disease resistance.

Comparative genomics provides a powerful tool for the identification of genes that encode traits shared between crop plants and model organisms. Pathogen resistance conferred by plant R genes of the nucleotide-binding-leucine-rich-repeat (NB-LRR) class is one such trait with great agricultural importance that occupies a critical position in understanding fundamental processes of pathogen detection and coevolution. The proposed rapid rearrangement of R genes in genome evolution would make comparative approaches tenuous. Here, we test the hypothesis that orthology is predictive of R-gene genomic location in the Solanaceae using the pepper R gene Bs2. Homologs of Bs2 were compared in terms of sequence and gene and protein architecture. Comparative mapping demonstrated that Bs2 shared macrosynteny with R genes that best fit criteria determined to be its orthologs. Analysis of the genomic sequence encompassing solanaceous R genes revealed the magnitude of transposon insertions and local duplications that resulted in the expansion of the Bs2 intron to 27 kb and the frequently detected duplications of the 5'-end of R genes. However, these duplications did not impact protein expression or function in transient assays. Taken together, our results support a conservation of synteny for NB-LRR genes and further show that their distribution in the genome has been consistent with global rearrangements.

Plant genomes encode large numbers of nucleotide binding and leucine-rich repeat (NB-LRR) proteins, some of which mediate the recognition of pathogen-encoded proteins. Following recognition, the initiation of a resistance response is thought to be mediated by the domains present at the N termini of NB-LRR proteins, either a Toll and Interleukin-1 Receptor or a coiled-coil (CC) domain. In order to understand the role of the CC domain in NB-LRR function, we have undertaken a systematic structure-function analysis of the CC domain of the potato (Solanum tuberosum) CC-NB-LRR protein Rx, which confers resistance to Potato virus X. We show that the highly conserved EDVID motif of the CC domain mediates an intramolecular interaction that is dependent on several domains within the rest of the Rx protein, including the NB and LRR domains. Other conserved and nonconserved regions of the CC domain mediate the interaction with the Ran GTPase-activating protein, RanGAP2, a protein required for Rx function. Furthermore, we show that the Rx NB domain is sufficient for inducing cell death typical of hypersensitive plant resistance responses. We describe a model of CC-NB-LRR function wherein the LRR and CC domains coregulate the signaling activity of the NB domain in a recognition-specific manner.

We present a case of spontaneous evisceration of the small bowel through the vaginal vault in a 61-year-old women. The predisposing factors and management are discussed.