Polygalacturonase-inhibiting proteins as an exogenously applied natural solution for prevention of postharvest fungal infections.

Polygalacturonase inhibiting proteins (PGIPs) are plant proteins involved in the inhibition of polygalacturonases (PGs), cell-wall degrading enzymes often secreted by phytopathogenic fungi. Previously, we confirmed that PGIP2 from Phaseolus vulgaris (PvPGIP2) can inhibit the growth of Aspergillus niger and Botrytis cinerea on agar plate. In this study, we further validated the feasibility of using PGIP as an environmental and ecological friendly agent to prevent fungal infection post-harvest. We found that application of either purified PGIP (full length PvPGIP2 or truncated tPvPGIP2_5-8), or PGIP-secreting Saccharomyces cerevisiae strains can effectively inhibit fungal growth and necrotic lesions on tobacco leaf. We also examined the effective amount and thermostability of PGIP when applied on plants. A concentration of 0.75 mg/mL or higher can significantly reduce the area of B. cinerea lesions. The activity of full-length PvPGIPs is not affected after incubation at various temperatures ranging from -20 to 42 °C for 24 h, while truncated tPvPGIP2_5-8 lost some efficacy after incubation at 42 °C. Furthermore, we have also examined the efficacy of PGIP on tomato fruit. When the purified PvPGIP2 proteins were applied to tomato fruit inoculated with B. cinerea at a concentration of roughly 1.0 mg/mL, disease incidence and area of disease had reduced by more than half compared to the controls without PGIP treatment. This study explores the potential of PGIPs as exogenously applied, eco-friendly fungal control agents on fruit and vegetables post-harvest.

Interventions to promote home radon testing: A randomized clinical trial of a smartphone app vs. printed brochures.

Radon is a preventable cause of lung cancer, but the percentage of homes tested for radon is low. We previously developed a smartphone app that informs users about radon and allows them to request a free radon test. Here we conducted a randomized, controlled trial comparing the radon app versus printed brochures on radon knowledge, attitudes, and behaviors, including the proportion of participants requesting radon tests. Participants (N = 138) were undergraduates at a midwestern university. Data were analyzed by t-tests, general linear models, and logistic regression. App users showed significantly greater increases in radon knowledge (p = 0.010) and self-efficacy (p < 0.001) and requested tests three times more often than brochure recipients (41.4% vs. 13.2%, p < 0.001). However, the rate of test usage in each condition was low, ~3%. In conclusion, the radon app markedly outperformed brochures in increasing knowledge and requests for radon tests. Future work should focus on methods to increase test usage.

The potential of plant proteins as antifungal agents for agricultural applications.

Fungal pathogens induce a variety of diseases in both plants and post-harvest food crops, resulting in significant crop losses for the agricultural industry. Although the usage of chemical-based fungicides is the most common way to control these diseases, they damage the environment, have the potential to harm human and animal life, and may lead to resistant fungal strains. Accordingly, there is an urgent need for diverse and effective agricultural fungicides that are environmentally- and eco-friendly. Plants have evolved various mechanisms in their innate immune system to defend against fungal pathogens, including soluble proteins secreted from plants with antifungal activities. These proteins can inhibit fungal growth and infection through a variety of mechanisms while exhibiting diverse functionality in addition to antifungal activity. In this mini review, we summarize and discuss the potential of using plant antifungal proteins for future agricultural applications from the perspective of bioengineering and biotechnology.

Exploring the potential of engineering polygalacturonase-inhibiting protein as an ecological, friendly, and nontoxic pest control agent.

In plants, polygalacturonase-inhibiting proteins (PGIPs) play critical roles for resistance to fungal disease by inhibiting the pectin-depolymerizing activity of endopolygalacturonases (PGs), one type of enzyme secreted by pathogens that compromises plant cell walls and leaves the plant susceptible to disease. Here, the interactions between PGIPs from Phaseolus vulgaris (PvPGIP1 and PvPGIP2) and PGs from Aspergillus niger (AnPG2), Botrytis cinerea (BcPG1 and BcPG2), and Fusarium moniliforme (FmPG3) were reconstituted through a yeast two hybrid (Y2H) system to investigate the inhibition efficiency of various PvPGIP1 and 2 truncations and mutants. We found that tPvPGIP2_5-8, which contains LRR5 to LRR8 and is only one-third the size of the full length peptide, exhibits the same level of interactions with AnPG and BcPGs as the full length PvPGIP2 via Y2H. The inhibitory activities of tPvPGIP2_5-8 on the growth of A. niger and B. cinerea were then examined and confirmed on pectin agar. On pectin assays, application of both full length PvPGIP2 and tPvPGIP2_5-8 clearly slows down the growth of A. niger and B. cinerea. Investigation on the sequence-function relationships of PGIP utilizing a combination of site directed mutagenesis and a variety of peptide truncations suggests that LRR5 could have the most essential structural feature for the inhibitory activities, and may be a possible target for the future engineering of PGIP with enhanced activity. This study highlights the potential of plant-derived PGIPs as a candidate for future in planta evaluation as a pest control agent.

Nonpharmacist Health Care Providers' Knowledge of and Opinions Regarding Medication Costs in Critically Ill Patients.

Purpose: Medication cost is frequently overlooked when treating critically ill patients. Stewardship of health care resources in high-utilization settings is imperative. This study was conducted to determine nonpharmacist health care providers' knowledge and perceptions of medication costs in a medical intensive care unit (MICU). Methods: Nonpharmacist health care providers in a MICU completed a 27-item survey. The survey queried perceptions regarding medication cost, cost-limiting strategies, and most/least expensive medications in 8 classes, medication price ranges, and intravenous-to-oral comparisons for commonly prescribed medications. Responses were analyzed using descriptive statistics and compared between providers using Fisher exact tests. Results: Among 98 health care providers (76 medical trainees, 5 attending physicians, 17 nurses), when ordering a medication, 49% consider its cost. Few (15%) providers considered themselves knowledgeable regarding medication costs with no difference between providers (P = .174). Attending physicians were more aware of the most/least expensive medications than residents (correct out of 16: 9.6 vs 8.5, P = .044). The correct price ranges for select medications (11%-36%, P = .373) and intravenous-to-oral relative costs (3%-49%, P = .596) were similarly low. Most (59%) believed pharmacists limit expensive medication use, particularly senior physicians (58% resident vs 100% attending, P = .007). Conclusion: In spite of a goal of cost consideration, most nonpharmacist health care providers are unaware of medication costs and fail to include them in decision making. These knowledge gaps and perceptions should inform future efforts to improve knowledge and attitudes regarding medication costs.