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After regulation of pesticides, determination of their persistence in the environment is an important indicator of effectiveness of these measures. We quantified concentrations of two types of systemic insecticides, neonicotinoids (imidacloprid, acetamiprid, clothianidin, thiacloprid, and thiamethoxam) and butenolides (flupyradifurone), in off-crop nontarget media of hummingbird cloacal fluid, honey bee (Apis mellifera) nectar and honey, and wildflowers before and after regulation of imidacloprid on highbush blueberries in Canada in April 2021. We found that mean total pesticide load increased in hummingbird cloacal fluid, nectar, and flower samples following imidacloprid regulation. On average, we did not find evidence of a decrease in imidacloprid concentrations after regulation. However, there were some decreases, some increases, and other cases with no changes in imidacloprid levels depending on the specific media, time point of sampling, and site type. At the same time, we found an overall increase in flupyradifurone, acetamiprid, thiamethoxam, and thiacloprid but no change in clothianidin concentrations. In particular, flupyradifurone concentrations observed in biota sampled near agricultural areas increased twofold in honey bee nectar, sevenfold in hummingbird cloacal fluid, and eightfold in flowers after the 2021 imidacloprid regulation. The highest residue detected was flupyradifurone at 665 ng/mL (parts per billion [ppb]) in honey bee nectar. Mean total pesticide loads were highest in honey samples (84 ± 10 ppb), followed by nectar (56 ± 7 ppb), then hummingbird cloacal fluid (1.8 ± 0.5 ppb), and least, flowers (0.51 ± 0.06 ppb). Our results highlight that limited regulation of imidacloprid does not immediately reduce residue concentrations, while other systemic insecticides, possibly replacement compounds, concurrently increase in wildlife. Environ Toxicol Chem 2024;43:1497-1508. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Insecticidas , Neonicotinoides , Nitrocompuestos , Neonicotinoides/análisis , Animales , Insecticidas/análisis , Nitrocompuestos/análisis , Piridinas/análisis , Abejas , Monitoreo del Ambiente , Aves , Néctar de las Plantas/química , Miel/análisis , Tiametoxam , Flores/química , Guanidinas , Tiazinas , Tiazoles , 4-Butirolactona/análogos & derivadosRESUMEN
Hummingbirds share biologically distinctive traits: sustained hovering flight, the smallest bird body size, and high metabolic rates fueled partially by nectar feeding that provides pollination to plant species. Being insectivorous and sometimes serving as prey to larger birds, they fulfill additional important ecological roles. Hummingbird species evolved and radiated into nearly every habitat in the Americas, with a core of species diversity in South America. Population declines of some of their species are increasing their risk of extinction. Threats to population health and genetic diversity are just beginning to be identified, including diseases and hazards caused by humans. We review the disciplines of population health, disease ecology, and genomics as they relate to hummingbirds. We appraise knowledge gaps, causes of morbidity and mortality including disease, and threats to population viability. Finally, we highlight areas of research need and provide ideas for future studies aimed at facilitating hummingbird conservation.
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Néctar de las Plantas , Polinización , Humanos , Animales , Aves/genética , GenómicaRESUMEN
Neonatology is a field that is currently facing many challenges. These challenges include outdated work models in clinical environments with increasing acuity and patient workloads, physician burnout exacerbated by gender inequity and the recent COVID-19 pandemic, and inappropriate metrics to measure clinical productivity. Academic neonatologists have additional missions that include research, teaching, and scholarly productivity in the setting of an increasing clinical workload and reduced time and support for teaching and research. Within the university-based practice setting, reimbursement, and salary structure result in relatively low compensation for neonatologist clinical productivity and time. These challenges threaten the sustainability of academic neonatology as a field. Working towards potential solutions such as creation of sustainable, transparent work models, and aligned funds flow within university-based settings is imperative.
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Neonatología , Médicos , Humanos , Neonatólogos , Pandemias , BenchmarkingRESUMEN
Cancers in the central nervous system resist therapies effective in other cancers, possibly due to the unique biochemistry of the human brain microenvironment composed of cerebrospinal fluid (CSF). However, the impact of CSF on cancer cells and therapeutic efficacy is unknown. Here, we examined the effect of human CSF on glioblastoma (GBM) tumors from 25 patients. We found that CSF induces tumor cell plasticity and resistance to standard GBM treatments (temozolomide and irradiation). We identified nuclear protein 1 (NUPR1), a transcription factor hampering ferroptosis, as a mediator of therapeutic resistance in CSF. NUPR1 inhibition with a repurposed antipsychotic, trifluoperazine, enhanced the killing of GBM cells resistant to chemoradiation in CSF. The same chemo-effective doses of trifluoperazine were safe for human neurons and astrocytes derived from pluripotent stem cells. These findings reveal that chemoradiation efficacy decreases in human CSF and suggest that combining trifluoperazine with standard care may improve the survival of patients with GBM.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/metabolismo , Trifluoperazina/farmacología , Trifluoperazina/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/metabolismo , Temozolomida/farmacología , Quimioradioterapia , Línea Celular Tumoral , Microambiente TumoralRESUMEN
Agriculture is one the main drivers of bird decline in both Europe and North America. While it is clear that agricultural practices and changes in the rural landscape directly and indirectly affect bird communities, we still do not know the extent to which these impacts might change across broad spatial and temporal scales. To address this question, we combined information on agricultural activities with occurrence and abundance of 358 bird species across five time periods spanning 20 years in Canada. As a proxy for agricultural impact, we used a combined index that included different agricultural metrics, such as cropland and tillage area and area treated with pesticides. We found that agriculture impact was negatively associated with bird diversity and evenness across all 20 years studied, but these associations seemed to vary by region. We found good support for an overall negative association between agriculture impact and bird diversity and evenness in the Eastern and Atlantic regions but weaker associations in the Prairies and Pacific. These findings suggest that agricultural activities result in bird communities that are less diverse and disproportionately benefit certain species. The spatial variation in the impact of agriculture on bird diversity and evenness we observed is likely a result of regional differences in the native vegetation, the type of crops and commodities produced, the historical context of agriculture, as well as the native bird community and the extent of their association with open habitat. Thus, our work provides support for the idea that the on-going agricultural impact on bird communities, while largely negative, is not uniform, and can vary across broad geographic regions.
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Biodiversidad , Ecosistema , Animales , Agricultura , Canadá , AvesAsunto(s)
Neonatólogos , Neonatología , Humanos , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Recursos HumanosRESUMEN
Background and Objectives: Palliative care addresses physical, emotional, psychological, and spiritual suffering that accompanies serious illness. Emphasis on symptom management and goals of care is especially valuable for seriously ill nursing home residents. We investigated barriers to nursing home palliative care provision highlighted by the coronavirus disease 2019 (COVID-19) pandemic and the solutions nursing home staff used to provide care in the face of those barriers. Research Design and Methods: For this descriptive qualitative study, seven Massachusetts nursing home directors of nursing were interviewed remotely about palliative care provision before and during the COVID-19 pandemic. Interview data were analyzed using thematic analysis. Results: Before the pandemic, palliative care was delivered primarily by nursing home staff depending on formal and informal consultations from palliative care specialists affiliated with hospice providers. When COVID-19 lockdowns precluded these consultations, nursing staff did their best to provide palliative care, but were often overwhelmed by shortfalls in resources, resident decline brought on by isolation and COVID-19 itself, and a sense that their expertise was lacking. Advance care planning conversations focused on hospitalization decisions and options for care given resource constraints. Nevertheless, nursing staff discovered previously untapped capacity to provide palliative care on-site as part of standard care, building trust of residents and families. Discussion and Implications: Nursing staff rose to the palliative care challenge during the COVID-19 pandemic, albeit with great effort. Consistent with prepandemic analysis, we conclude that nursing home payment and quality standards should support development of in-house staff capacity to deliver palliative care while expanding access to the formal consultations and family involvement that were restricted by the pandemic. Future research should be directed to evaluating initiatives that pursue these aims.
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Detailed information spanning the full annual cycle is lacking for most songbird populations. We examined breeding, migration, and non-breeding sites for the Yellow-breasted Chat (Icteria virens, chat). We deployed archival GPS tags and light-level geolocators on breeding chats in British Columbia and light-level geolocators in California from 2013 to 2017 to determine migration routes and non-breeding sites. We examined whether chats overwintered in protected areas and characterized the percent of land cover within 1 km. We used a combination of genetics and stable hydrogen isotopes from feathers collected on non-breeding chats in Nayarit, Mexico (2017-2019) and migrating chats in Chiapas, Mexico (2018) and Veracruz, Mexico (2014-2015) to determine subspecies and infer breeding location. Endangered chats in British Columbia followed the Pacific Flyway and spent the non-breeding period in Sinaloa and Nayarit, Mexico. Two out of five chats spent the non-breeding period in protected areas, and the most common landcover type used was tropical or subtropical broadleaf deciduous forest. We found no mixing of eastern and western chats in our Mexico sites, suggesting strong migratory connectivity at the subspecies level. Western chats likely originating from multiple breeding latitudes spent the non-breeding period in Nayarit. Eastern Yellow-breasted Chats likely breeding across various latitudes migrated through Veracruz and Chiapas. Our results provide precise migration routes and non-breeding locations, and describe habitat cover types for chats, notably an endangered population in British Columbia, which may be valuable for habitat protection and conservation efforts. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10336-021-01931-8.
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Open-pit mining operations are hailed for safe working conditions for miners as well as economically and logistically favourable outcomes for mining companies. However, ecological impacts of these operations may persist for decades. Expansions of open-pit coal mining in British Columbia of Western Canada are planned. Governmental regulation of background contaminants leached from these mines into nearby water systems were established to mitigate environmental impacts associated with these operations. We analyzed water, periphyton, invertebrate, and American dipper (Cinclus mexicanus) blood, egg, and feather samples for selenium and mercury exposure related to mining operations in the Elk Valley. We also quantified effects associated with exposure on clutch size and hatching success. Selenium concentrations in water, periphyton, and invertebrates were significantly higher downstream of mines compared to reference sites within and outside of the Elk River watershed. Selenium concentrations in water from exposed sites exceeded current regulatory levels established to protect wildlife by up to 20 times. Mercury concentrations were below toxic levels for birds in all media and did not factor into determination of selenium exposure or effects. Egg selenium concentrations were on average 0.9 times the regulatory threshold. Our stable isotope analyses showed that diets of nesting females included a negligible proportion of higher order consumers. We did not detect a significant effect of selenium on the rate of hatching success or clutch size of dippers nesting in exposed sites. We conclude that at the time of the investigation, selenium exposure was not impairing hatching of American dippers at the sampled locations.
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Minas de Carbón , Selenio , Pájaros Cantores , Contaminantes Químicos del Agua , Animales , Bioacumulación , Colombia Británica , Monitoreo del Ambiente , Minería , Selenio/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidadRESUMEN
Mercury (Hg) is an environmental contaminant that can negatively impact human and wildlife health. For songbirds, Hg risk may be elevated near riparian habitats due to the transfer of methylmercury (MeHg) from aquatic to terrestrial food webs. We measured Hg levels in tail feathers sampled across the breeding range of the Yellow-breasted Chat (Icteria virens), a riparian songbird species of conservation concern. We assessed the risk of Hg toxicity based on published benchmarks. Simultaneously, we measured corticosterone, a hormone implicated in the stress response system, released via the hypothalamus-pituitary-adrenal axis. To better understand range-wide trends in Hg and corticosterone, we examined whether age, sex, subspecies, or range position were important predictors. Lastly, we examined whether Hg and corticosterone were correlated. Hg levels in chats were relatively low: 0.30 ± 0.02 µg/g dry weight. 148 out of 150 (98.6%) had Hg levels considered background, and 2 (1.6%) had levels considered low toxicity risk. Hg levels were similar between sexes and subspecies. Younger chats (<1 year) had higher Hg levels than older chats (>1 year). Hg levels were lowest in the northern and central portion of the eastern subspecies' range. Corticosterone concentrations in feathers averaged 3.68 ± 0.23 pg/mm. Corticosterone levels were similar between ages and sexes. Western chats had higher levels of corticosterone than eastern chats. Hg and corticosterone were not correlated, suggesting these low Hg burdens did not affect the activity of the hypothalamus-pituitary-adrenal axis. Altogether, the chat has low Hg toxicity risk across its breeding range, despite living in riparian habitats.
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Mercurio , Compuestos de Metilmercurio , Passeriformes , Animales , Corticosterona , Monitoreo del Ambiente , Humanos , Mercurio/análisis , Mercurio/toxicidad , Compuestos de Metilmercurio/toxicidadRESUMEN
As pollinators, hummingbirds play a critical role for both the function of ecological communities and in providing ecosystem services for people. To examine the conservation status of North American hummingbirds, we analyzed Breeding Bird Survey data for 8 species and 3 genera from 1970 to 2019 (long-term) and from 2009 to 2019 (short-term, approximately three generations). Among the Selasphorus genus, Allen's, rufous, and broad-tailed hummingbirds have declined since 1970, and the rate of decline increased from 2009 to 2019. Contrasting the trends from the past half-century, ruby-throated hummingbirds of Eastern North America have declined since approximately 2004 throughout most of the species' breeding range. In contrast, Anna's hummingbird populations have increased dramatically since 1970 in their range in western North America. We also tested whether apparent declines might be due to a growing mismatch between the timing of breeding and the timing of BBS surveys. We found no evidence for such an effect, thus supporting the hypothesis that trends reflect true demographic change. Our analyses and geographic modelling highlight the urgent need of regulatory action to conserve hummingbirds uniquely capable of filling their niche in North America.
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Aves/fisiología , Especies en Peligro de Extinción/tendencias , Animales , Ecosistema , América del NorteRESUMEN
Dichlorodiphenyldichlorethane (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) (DDT) is an organochlorine insecticide that was widely used from the late 1940s to the 1970s in fruit orchards in the Okanagan valley, British Columbia, Canada, and in the process, contaminated American robin (Turdus migratorius) food chains with the parent compound and metabolite dichlorodiphenyldichloroethylene (1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene) (p,p'-DDE). In the present study, we examined the biological fate of these DDT-related (DDT-r) compounds at the same sites/region 26 years after a previous study by: (1) collecting soil, earthworms, and American robin eggs from apple, cherry, and pear orchards; (2) characterizing the diet and trophic positions of our biota using stable isotope analyses of δ13 C and δ15 N; and (3) estimating fugacity, biota-soil-accumulation factors (BSAFs), and biomagnification factors (BMFs). Mean p,p'-DDE concentrations (soil: 16.1 µg/g organic carbon-lipid equivalent; earthworms: 96.5 µg/g lipid equivalent; eggs: 568 µg/g lipid equivalent) revealed that contamination is present at elevated levels similar to the 1990s and our average soil DDE:DDT ratio of 1.42 confirmed that DDT is slowly degrading. American robins appeared to feed at similar trophic levels, but on different earthworms as indicated by egg stable isotope values (mean δ15 N = 8.51 ± 0.25; δ13 C = -26.32 ± 0.12). Lumbricidae and Aporrectodea worms shared a roughly similar δ15 N value; however, Lumbricus terrestris showed a markedly enriched δ13 C isotope, suggesting differences in organic matter consumption and physiological bioavailability. Biota-soil-accumulation factors and BMFs ranged over several orders of magnitude and were generally >1 and our fugacity analyses suggested that p,p'-DDE is still thermodynamically biomagnifying in American robin food chains. Our results demonstrate that DDT-r in fruit orchards remains bioavailable to free-living terrestrial passerines and may pose a potential toxicological risk. Environ Toxicol Chem 2021;40:3379-3391. © 2021 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.
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DDT , Cadena Alimentaria , Animales , Bioacumulación , Colombia Británica , DDT/análisis , Diclorodifenil Dicloroetileno/análisis , Femenino , Frutas/química , Frutas/metabolismoRESUMEN
We analyzed the reproductive success of eastern bluebirds (Sialia sialis) nesting in apple orchards and non-orchard nest-boxes in southern Ontario, Canada, from 1988 to 2018. Using data from 2397 nest-boxes monitored at 20 orchard sites and 52 non-orchard sites, we first modeled phenological parameters typically linked to climate change across both site types. We found that the first egg of each brood was laid significantly earlier in the season each year over our 31-year study. Clutch initiation occurred 4 days earlier in the spring in 2018 compared to 1988. Average clutch size in the first or second brood did not change significantly during our 31-year study; however, clutches were significantly smaller in orchards compared to non-orchards (0.10 ± 0.03 fewer eggs between sites). Nests built in orchards were also at 6.1-fold greater risk of parasitism and 2.1-fold greater risk of depredation than nests in non-orchards. After accounting for depredation and nest parasitism, hatching success was still significantly lower in orchards than in non-orchards. Overall, hatching success was 4%-5% lower in orchards. The probability of successfully fledging did not differ significantly between site types. In 2012, a ban on use of the organophosphate insecticide azinphos-methyl in orchards was enacted in Canada. We did not find a difference in hatching or fledging success in orchards after the ban. In our assessment of available data, we conclude that any pesticide effect on hatching success of eastern bluebirds in sprayed orchards is most likely the consequence of long-term exposure to dichlorodiphenyltrichloroethane (DDT) compounds in orchard soils and bioaccumulation in eggs rather than pesticides in use since regulation of DDT in the 1970s. Environ Toxicol Chem 2021;40:3369-3378. © 2021 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.
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Malus , Plaguicidas , Pájaros Cantores , Animales , Ecosistema , Femenino , OntarioRESUMEN
BACKGROUND: Integrating bioethical concepts into preclinical medical school curriculum and engaging early medical learners in bioethics are a challenge. ACTIVITY: A total of 140 medical students participated in a 2-h simulation activity consisting of a series of standardized patient (SP) encounters. RESULTS: A total of 41 of 140 students (29%) completed the learner evaluation survey. Ninety-one percent thought that the SP encounter was relevant to their role as a future physician. Ninety-three percent of students rated the exercise as highly effective. CONCLUSIONS: SP encounters enhance preclinical medical students' engagement with bioethics and provide learners practice applying these concepts to clinically relevant scenarios.
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OBJECTIVES: To examine characteristics and outcomes of T18 and T13 infants receiving intensive surgical and medical treatment compared to those receiving non-intensive treatment in NICUs. STUDY DESIGN: Retrospective cohort of infants in the Children's Hospitals National Consortium (CHNC) from 2010 to 2016 categorized into three groups by treatment received: surgical, intensive medical, or non-intensive. RESULTS: Among 467 infants admitted, 62% received intensive medical treatment; 27% received surgical treatment. The most common surgery was a gastrostomy tube. Survival in infants who received surgeries was 51%; intensive medical treatment was 30%, and non-intensive treatment was 72%. Infants receiving surgeries spent more time in the NICU and were more likely to receive oxygen and feeding support at discharge. CONCLUSIONS: Infants with T13 or T18 at CHNC NICUs represent a select group for whom parents may have desired more intensive treatment. Survival to NICU discharge was possible, and surviving infants had a longer hospital stay and needed more discharge supports.