Ecdysteroid responses to urban heat island conditions during development of the western black widow spider (Latrodectus hesperus).

The steroid hormone 20-hydroxyecdysone (20E) controls molting in arthropods. The timing of 20E production, and subsequent developmental transitions, is influenced by a variety of environmental factors including nutrition, photoperiod, and temperature, which is particularly relevant in the face of climate change. Environmental changes, combined with rapid urbanization, and the increasing prevalence of urban heat islands (UHI) have contributed to an overall decrease in biodiversity making it critical to understand how organisms respond to elevating global temperatures. Some arthropods, such as the Western black widow spider, Latrodectus hesperus, appear to thrive under UHI conditions, but the physiological mechanism underlying their success has not been explored. Here we examine the relationship between hemolymph 20E titers and spiderling development under non-urban desert (27°C), intermediate (30°C), and urban (33°C) temperatures. We found that a presumptive molt-inducing 20E peak observed in spiders at non-urban desert temperatures was reduced and delayed at higher temperatures. Intermolt 20E titers were also significantly altered in spiders reared under UHI temperatures. Despite the apparent success of black widows in urban environments, we noted that, coincident with the effects on 20E, there were numerous negative effects of elevated temperatures on spiderling development. The differential effects of temperature on pre-molt and intermolt 20E titers suggest distinct hormonal mechanisms underlying the physiological, developmental, and behavioral response to heat, allowing spiders to better cope with urban environments.

Understanding medication use behaviors and perspectives in an older cardiovascular patient population: Opportunities for patient-centered deprescribing.

Study objective: Describe self-reported medication use behaviors and perspectives to identify opportunities for collaborative deprescribing among older cardiovascular patients. Design: Patient survey using convenience sampling. Setting: Private cardiology practice in Maricopa County, Arizona, USA. Participants: Established patients aged ≥65 years with an active medication list indicating prescription polypharmacy (≥5 medications) and/or use of ≥1 high risk medication (anticoagulant, antiarrhythmic, anti-hypotensive, insulin). Intervention: Anonymous online survey. Main outcome measures: Current medication use (prescription and over-the-counter), self-reported medication use behaviors measured by the Adherence to Refills and Medications Scale (ARMS-12), and perspectives on deprescribing. Results: Overall, 138 participants were recruited, with a mean age of 76.7 years. All but two self-identified as Caucasian. Prescription polypharmacy was reported by 80 (58.0 %), with use of 5-9 medications by 66 (47.8 %) and use of ≥10 medications (excessive polypharmacy) by 14 (10.1 %). Approximately one-third (n = 45, 32.6 %) had ARMS = 12, indicating adherence to taking and refilling medications. More than 1 in 10 patients (11.6 %) used >1 high-risk medication. About 4 in 10 (40.6 %) used ≥5 OTC medications. Most highly prioritized reasons for continuing medications were to prolong life (40 %), feel better (17 %), and reduce stroke risk (15 %). Despite 66.7 % of patients indicating taking "just the right amount of medications," willingness to stop ≥1 medication was very high at 80.4 %. Conclusion: Among older cardiovascular patients, prescription polypharmacy is prevalent as are medication use behaviors associated with some degree of nonadherence. Patients are supportive of deprescribing. Prioritizing what matters most to patients and focusing efforts to deprescribe potentially inappropriate medications is recommended.

Urban heat island conditions experienced by the Western black widow spider (Latrodectus hesperus): Extreme heat slows development but results in behavioral accommodations.

While shifts in organismal biology stemming from climate change are receiving increased attention, we know relatively little about how organisms respond to other forms of anthropogenic disturbance. The urban heat island (UHI) effect describes the capture of heat by built structures (e.g. asphalt), resulting in elevated urban temperatures. The UHI is a well-studied phenomenon, but only a handful of studies have investigated trait-based shifts resulting from the UHI, and even fewer have attempted to quantify the magnitude of the UHI experienced at the microclimate scale. Here, using a common urban exploiter, the Western black widow spider (Latrodectus hesperus), we show that the UHI experienced by spiders in July in their urban Phoenix, AZ refuges is 6°C hotter (33°C) than conditions in the refuges of spiders from Sonoran Desert habitat outside of Phoenix's development (27°C). We then use this field microclimate UHI estimate to compare the development speed, mass gain and mortality of replicate siblings from 36 urban lineages reared at 'urban' and 'desert' temperatures. We show that extreme heat is slowing the growth of spiderlings and increasing mortality. In contrast, we show that development of male spiders to their penultimate moult is accelerated by 2 weeks. Lastly, in terms of behavioral shifts, UHI temperatures caused late-stage juvenile male spiders to heighten their foraging voracity and late-stage juvenile female spiders to curtail their web-building behavior. Trait-based approaches like the one presented herein help us better understand the mechanisms that lead to the explosive population growth of urban (sometimes invasive) species, possibly at the expense of urban biodiversity. Studies of organismal responses to the present day UHI can be used as informative surrogates that help us grasp the impact that projected climate change will have on biodiversity.