Wild and managed bees are critical for the stability of trophic webs, angiosperm reproduction, and agricultural productivity. Unfortunately, as many as 40% of crop pollinators are in a steep decline due to habitat loss and exposure to agrochemicals. Pyrethroids, neonicotinoids, and macrocyclic lactones are among the many agrochemicals toxic to pollinating insects that are used extensively in industrial beef cattle feeding operations throughout the world.
View Article and Find Full Text PDFPollinator population declines are global phenomena with severe consequences for native flora and agriculture. Many factors have contributed to pollinator declines including habitat loss, climate change, disease and parasitism, reductions in abundance and diversity of foraging resources, and agrochemical exposure. Particulate matter (PM) serves as a carrier of toxic agrochemicals, and pollinator mortality can occur following exposure to agrochemical-contaminated PM.
View Article and Find Full Text PDFBeef cattle feedlot particulate matter (PM) is a complex mixture of dust, animal waste, agrochemicals, and bioaerosols. However, no empirical data exist quantifying downwind residential exposure to PM or PM-bound agrochemicals. In the current study, authors investigated transport of PM and co-occurring insecticides and anthelmintics downwind of three feedlots in the Southern Great Plains (SGP) of North America from May-August 2022.
View Article and Find Full Text PDFEnvironmental transport and deposition of particulate matter (PM) associated with toxic chemicals has begun to receive attention as a source of risk to pollinators. For example, dust arising from manipulations of insecticide-treated seed has potential to exert toxic effects among non-target insects. Similarly, synthetic steroid growth promoters, antibiotics and multiple insecticides and parasiticides detected in fugitive beef cattle feedyard PM may also negatively impact pollinators since many of these chemicals have been detected on wildflowers and pollinators collected near beef cattle feedyards.
View Article and Find Full Text PDFIndustrial cattle feeding operations (feedlots) have been subject to public scrutiny in recent decades regarding environmental impacts of site runoff and aerial dispersion of agrochemical-laden particulate matter (PM). However, source apportionment of multi-use pesticides is challenging in mixed agricultural settings. Beef cattle on feed and row crop production are heavily concentrated in the Southern Great Plains of North America, where playa wetlands are vulnerable to agrochemical inputs and sedimentation from surrounding land use.
View Article and Find Full Text PDFIt is well established that agrochemicals can pose significant threats to native pollinators; however, relatively little is known about pollinator risks associated with agrochemicals that are used on beef cattle feed yards. Recently, feed yard-derived agrochemicals and those from row crop agriculture were quantified on wildflowers growing on the High Plains, USA. To better characterize pollinator risks on the High Plains, we collected colocated wildflowers and foraging bees across three field seasons for analytical determination of residual agrochemicals.
View Article and Find Full Text PDFAnalysis of particulate matter originating from beef cattle feed yards on the High Plains of the United States has revealed occurrence of multiple pesticides believed to potentially impact non-Apis pollinators. Among these pesticides are those that are highly toxic to Apis mellifera (honey bees). However, little non-Apis bee species toxicity data exist; especially pertaining to beef cattle feed yard-derived pesticides.
View Article and Find Full Text PDFConsidering the recent discovery of veterinary pharmaceutical aerial transport from industrial cattle feeding operations via particulate matter, the objective of this study is to determine the extent to which insecticides are also transported into the environment by total suspended particulates emanating from beef cattle feed yards. Of 16 different pesticides quantified in particulate matter samples collected from beef cattle feed yards, permethrin was detected most frequently at >67% of particulate matter samples and at a mean concentration of 1211.7 ± 781.
View Article and Find Full Text PDFA chemical contaminant of growing concern to freshwater aquatic organisms, including many amphibians, is chloride ion. The salinization of freshwater ecosystems is likely caused, in part, by the application of massive amounts of road de-icing salts to roadways during winter months. The issue of freshwater salinization has become the subject of many toxicity studies and is often investigated in conjunction with other chemical stressors.
View Article and Find Full Text PDFAn important challenge in amphibian ecotoxicology and conservation is that amphibian toxicity tests are usually focused on a single chemical while populations experience multiple, simultaneous stressors. For example, about 14 million tons of road de-icing salts are used each year in North America with NaCl accounting for 98% of total salt use and, hence, elevated chloride is an important environmental stressor to aquatic organisms, including amphibians. As well, higher temperature as a result of climate change is becoming an increasingly important environmental stressor.
View Article and Find Full Text PDFPurpose: To assess the complication rates and visual outcomes of manual small incision cataract surgery (MSICS) in a university teaching hospital setting.
Method: Retrospective audit encompassing a 3-year period looking at the visual outcomes, and intraoperative and postoperative complications of planned MSICS performed on brunescent cataracts.
Results: MSICS was performed in 55 eyes of 49 patients.
Transferrin receptor 2 (TfR2) is a homologue of transferrin receptor 1 (TfR1), the protein that delivers iron to cells through receptor-mediated endocytosis of diferric transferrin (Fe(2)Tf). TfR2 also binds Fe(2)Tf, but it seems to function primarily in the regulation of systemic iron homeostasis. In contrast to TfR1, the trafficking of TfR2 within the cell has not been extensively characterized.
View Article and Find Full Text PDFA yeast two-hybrid screen identified a specific interaction between the cytoplasmic domain of transferrin receptor (TfR) and GABARAP, a 14 kDa protein that binds to the gamma2 subunit of neuronal GABA(A) receptors. The specificity of the TfR-GABARAP interaction was demonstrated by in vitro binding assays with purified proteins and by co-immunoprecipitation of GABARAP with endogenous TfR from HeLa cell lysates. Replacement of the YTRF internalization motif with ATRA within the cytoplasmic domain of TfR reduced interaction with GABARAP in the yeast two-hybrid screen and in vitro binding assays.
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