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Major strike-slip faults that develop between strong and weaker regions are thought to focus along narrow shear zones at the rheological boundary. Here we present the InSAR-derived velocity field spanning almost the entire length of one such fault, the 1600 km-long Altyn Tagh Fault (ATF), and analyse the strain distribution. We find that localisation of strain is actually variable, in contrast to other major strike-slip faults that show little variation, with strain concentrated at the fault for some sections and distributed over broad (>100 km) shear zones for others. Slip rate along the ATF is also variable, decreasing along the fault from 11.6 ± 1.6 mm/yr in the west to 7.2 ± 1.4 mm/yr in the central portion, before increasing again to 11.7 ± 0.9 mm/yr over the eastern portion. We show that the variable shear zone width may be linked to geological variability and the influence of heat flow, and the results imply that sub-parallel faults play an important role in the overall deformation field. This demonstrates the significance of accurately characterising strain rates over a broad region when assessing seismic hazard.
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Biocompatibility testing using in vivo tests is often one of the final evaluations of new dental materials. To reduce the likelihood of failure at this late stage, predictive biocompatibility testing using in vitro methods is needed. In this study, we describe a sensitivity analysis of an oral irritation test by evaluating changes in the viability, using the MTT assay, of 3-D models with EpiOral constructs as a case study. Experiments that tested sources of variability in the assay led to recommendations regarding the storage of the constructs after arrival, pipetting procedure, use of MTT reagents from different vendors, use of transepithelial electrical resistance measurements, and statistical analyses. A statistical model was proposed to evaluate whether test substances yield a positive or negative result and the associated statistical confidence. Testing several test compounds such as the Y-4 polymer, that contains a known irritant, and dentally relevant substances such as sodium dodecyl sulfate (SDS) at varying concentrations revealed statistically significant results as expected. Lastly, a software app was designed to support a multiwell culture plate layout design. Overall, the findings and suggestions documented here will support the further development and potential standardization of this assay system and may be useful for the development of other assays using 3-D constructs.
New in vitro methods can support the development of novel dental materials by yielding information about their biocompatibility. In this study, an in vitro oral irritation assay was investigated to better understand what aspects of the method contribute to its variability. There is a potential that such a method could yield similar information to in vivo experiments and reduce animal testing.
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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
Repeatability of measurements from image analytics is difficult, due to the heterogeneity and complexity of cell samples, exact microscope stage positioning, and slide thickness. We present a method to define and use a reference focal plane that provides repeatable measurements with very high accuracy, by relying on control beads as reference material and a convolutional neural network focused on the control bead images. Previously we defined a reference effective focal plane (REFP) based on the image gradient of bead edges and three specific bead image features. This paper both generalizes and improves on this previous work. First, we refine the definition of the REFP by fitting a cubic spline to describe the relationship between the distance from a bead's center and pixel intensity and by sharing information across experiments, exposures, and fields of view. Second, we remove our reliance on image features that behave differently from one instrument to another. Instead, we apply a convolutional regression neural network (ResNet 18) trained on cropped bead images that is generalizable to multiple microscopes. Our ResNet 18 network predicts the location of the REFP with only a single inferenced image acquisition that can be taken across a wide range of focal planes and exposure times. We illustrate the different strategies and hyperparameter optimization of the ResNet 18 to achieve a high prediction accuracy with an uncertainty for every image tested coming within the microscope repeatability measure of 7.5 µm from the desired focal plane. We demonstrate the generalizability of this methodology by applying it to two different optical systems and show that this level of accuracy can be achieved using only 6 beads per image.
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Hutchison's niche theory suggests that coexisting competing species occupy non-overlapping hypervolumes, which are theoretical spaces encompassing more than three dimensions, within an n-dimensional space. The analysis of multiple stable isotopes can be used to test these ideas where each isotope can be considered a dimension of niche space. These hypervolumes may change over time in response to variation in behaviour or habitat, within or among species, consequently changing the niche space itself. Here, we use isotopic values of carbon and nitrogen of ten amino acids, as well as sulphur isotopic values, to produce multi-isotope models to examine niche segregation among an assemblage of five coexisting seabird species (ancient murrelet Synthliboramphus antiquus, double-crested cormorant Phalacrocorax auritus, Leach's storm-petrel Oceanodrama leucorhoa, rhinoceros auklet Cerorhinca monocerata, pelagic cormorant Phalacrocorax pelagicus) that inhabit coastal British Columbia. When only one or two isotope dimensions were considered, the five species overlapped considerably, but segregation increased in more dimensions, but often in complex ways. Thus, each of the five species occupied their own isotopic hypervolume (niche), but that became apparent only when factoring the increased information from sulphur and amino acid specific isotope values, rather than just relying on proxies of δ15N and δ13C alone. For cormorants, there was reduction of niche size for both species consistent with a decline in their dominant prey, Pacific herring Clupea pallasii, from 1970 to 2006. Consistent with niche theory, cormorant species showed segregation across time, with the double-crested demonstrating a marked change in diet in response to prey shifts in a higher dimensional space. In brief, incorporating multiple isotopes (sulfur, PC1 of δ15N [baselines], PC2 of δ15N [trophic position], PC1 and PC2 of δ13C) metrics allowed us to infer changes and differences in food web topology that were not apparent from classic carbon-nitrogen biplots.
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Aminoácidos , Charadriiformes , Animales , Aminoácidos/metabolismo , Isótopos/metabolismo , Aves/metabolismo , Nitrógeno/metabolismo , Carbono/metabolismo , Azufre/metabolismo , Isótopos de Nitrógeno/metabolismo , Isótopos de Carbono/metabolismoRESUMEN
OBJECTIVE: To determine headache diagnosis and treatment patterns in the outpatient setting, focusing on documentation of the International Classification of Headache Disorders (ICHD) criteria. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort data were collected from electronic medical records of adults aged 18-35 who presented to resident-staffed family medicine outpatient clinics in the Midwest, USA, for a new or worsening headache between 2015 and 2016. Diagnosis codes were used to summarize the overall nature and prevalence of headaches. A random subset of 30 patients each for migraine headache (MGH) with and without aura and tension-type headache (TTH) were reviewed to determine how many of the five possible ICHD criteria were documented. Demographics/clinical characteristics, ICHD criteria, number and type of medications, and healthcare utilization (imaging, primary and emergency department care) through one year following the initial visit were summarized and compared across headache types. RESULTS: There were 716 unique patients during the study period (414 MGH, 227 unspecified headaches, 75 TTH, or others). Complete ICHD criteria were documented for two patients in total. There was partial documentation (e.g., one to four of the possible five) for 30% of TTH, 63% of MGH without aura, and 77% of MGH with aura (p<0.05). Across headache types, patients were prescribed an average of 2.3 to 3.3 medications over one year, with MGH patients generally trying more medications (up to eight for those with aura and up to 12 for those without). Abortive or rescue medications were prescribed to nearly all patients; prophylactics were prescribed for 50% of MGH with aura, 66.7% of MGH without aura, and 53.3%. Non-pharmacologic interventions were less prescribed: 33.3% of TTH patients and 3.3% of MGH types combined (p<0.05). Healthcare utilization was highest for MGH with aura (ED visits) and without aura (clinic visits) patients compared to TTH (p<0.001). CONCLUSION: Headache-related documentation is often incomplete, which may limit interpretation and associations between diagnoses, prescribing patterns, and healthcare utilization. Future studies should evaluate the use of electronic medical records (EMR)-based templates to improve documentation, and additional detailed studies are needed in the local setting to determine whether treatment, including the use of non-pharmacologic and prophylactic methods of treatment, is optimal.
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Anticoagulant rodenticides (ARs) have caused widespread contamination and poisoning of predators and scavengers. The diagnosis of toxicity proceeds from evidence of hemorrhage, and subsequent detection of residues in liver. Many factors confound the assessment of AR poisoning, particularly exposure dose, timing and frequency of exposure, and individual and taxon-specific variables. There is a need, therefore, for better AR toxicity criteria. To respond, we compiled a database of second-generation anticoagulant rodenticide (SGAR) residues in liver and postmortem evaluations of 951 terrestrial raptor carcasses from Canada and the United States, 1989 to 2021. We developed mixed-effects logistic regression models to produce specific probability curves of the toxicity of ∑SGARs at the taxonomic level of the family, and separately for three SGARs registered in North America, brodifacoum, bromadiolone, and difethialone. The ∑SGAR threshold concentrations for diagnosis of coagulopathy at 0.20 probability of risk were highest for strigid owls (15 ng g-1) lower and relatively similar for accipitrid hawks and eagles (8.2 ng g-1) and falcons (7.9 ng g-1), and much lower for tytonid barn owls (0.32 ng g-1). These values are lower than those we found previously, due to compilation and use of a larger database with a mix of species and source locations, and also to refinements in the statistical methods. Our presentation of results on the family taxonomic level should aid in the global applicability of the numbers. We also collated a subset of 440 single-compound exposure events and determined the probability of SGAR-poisoning symptoms as a function of SGAR concentration, which we then used to estimate relative SGAR toxicity and toxic equivalence factors: difethialone, 1, brodifacoum, 0.8, and bromadiolone, 0.5. Environ Toxicol Chem 2024;43:988-998. © 2024 His Majesty the King in Right of Canada and The Authors. 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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Anticoagulantes , Rapaces , Rodenticidas , Rodenticidas/toxicidad , Animales , Anticoagulantes/toxicidad , Anticoagulantes/envenenamiento , 4-Hidroxicumarinas/envenenamiento , 4-Hidroxicumarinas/toxicidad , Canadá , Monitoreo del AmbienteRESUMEN
Metal-organic frameworks (MOFs) have captured the imagination of researchers for their highly tunable properties and many potential applications, including as catalysts for a variety of transformations. Even though MOFs possess significant potential, the challenges associated with processing of these crystalline powders into usable form factors while retaining their functional properties limit their end use applications. Herein, we introduce a new approach to construct MOF-polymer composites via 3D photoprinting to overcome these limitations. We designed photoresin composite formulations that use polymerization-induced phase separation to cause the MOF catalysts to migrate to the surface of the printed material, where they are accessible to substrates such as chemical warfare agents. Using our approach, MOF-polymer composites can be fabricated into nearly any shape or architecture while retaining both the excellent catalytic activity at 10 wt % loading of the MOF components and the flexible, elastomeric mechanical properties of a polymer.
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Many jurisdictions require ecological risk assessments for terrestrial wildlife (i.e., terrestrial vertebrates) to assess potential adverse effects from exposure to anthropogenic chemicals. This occurs, for example, at contaminated sites and when new pesticides are proposed, and it occurs for chemicals that are in production and/or proposed for wide-scale use. However, guidance to evaluate such risks has not changed markedly in decades, despite the availability of new scientific tools to do so. In 2019, the Wildlife Toxicology World Interest Group of the Society of Environmental Toxicology and Chemistry (SETAC) initiated a virtual workshop that included a special session coincident with the annual SETAC North America meeting and which focused on the prospect of improving risk assessments for wildlife and improving their use in implementing chemical regulations. Work groups continued the work and investigated the utility of integrating emerging science and novel methods for improving problem formulation (WG1), exposure (WG2), toxicology (WG3), and risk characterization (WG4). Here we provide a summary of that workshop and the follow-up work, the regulations that drive risk assessment, and the key focus areas identified to advance the ability to predict risks of chemicals to wildlife. Integr Environ Assess Manag 2024;20:645-657. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).
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Animales Salvajes , Plaguicidas , Animales , Ecotoxicología , Medición de Riesgo/métodos , Plaguicidas/toxicidad , América del NorteRESUMEN
Background: The liability of plastic surgery tourism in patient health and postoperative resource allocation is significant. Procedures completed within the context of medical tourism often lack rigorous quality assurance and provide limited preoperative evaluation or postoperative care. Not only does this jeopardize the patient's well-being, but it also increases the financial burden and redirects invaluable resources domestically through often unnecessary diagnostic tests and hospitalizations. Objectives: This manuscript will examine the complications and associated costs following plastic surgery tourism and highlight unnecessary expenses for patients with outpatient complications. Methods: A retrospective review was conducted of all patients 18 years or older who underwent destination surgery and were seen within 1 year postoperatively in consultation with plastic surgery at our health system between January 11, 2015 and January 7, 2022. Patient admissions were reviewed and deemed necessary or unnecessary after review by 2 physicians. Results: The inclusion criteria were met by 41 patients, of whom hospitalization was deemed necessary in 28 patients vs unnecessary in 13 patients. The most common procedures included abdominoplasty, liposuction, breast augmentation, and "Brazilian butt lift." The most common complications were seroma and infection. Patients deemed to have a necessary admission often required at least 1 operation, were more likely to need intravenous antibiotics, were less likely to have the diagnosis of "pain," necessitated a longer hospitalization, and incurred a higher cost. The total financial burden was $523,272 for all 41 patients. Conclusions: Plastic surgery tourism poses substantial health risks, the morbidities are expensive, and it strains hospital resources.
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Dermatitis Alérgica por Contacto , Dermatología , Humanos , Propilenglicol , Pruebas del ParcheRESUMEN
Model species (e.g., granivorous gamebirds, waterfowl, passerines, domesticated rodents) have been used for decades in guideline laboratory tests to generate survival, growth, and reproductive data for prospective ecological risk assessments (ERAs) for birds and mammals, while officially adopted risk assessment schemes for amphibians and reptiles do not exist. There are recognized shortcomings of current in vivo methods as well as uncertainty around the extent to which species with different life histories (e.g., terrestrial amphibians, reptiles, bats) than these commonly used models are protected by existing ERA frameworks. Approaches other than validating additional animal models for testing are being developed, but the incorporation of such new approach methodologies (NAMs) into risk assessment frameworks will require robust validations against in vivo responses. This takes time, and the ability to extrapolate findings from nonanimal studies to organism- and population-level effects in terrestrial wildlife remains weak. Failure to adequately anticipate and predict hazards could have economic and potentially even legal consequences for regulators and product registrants. In order to be able to use fewer animals or replace them altogether in the long term, vertebrate use and whole organism data will be needed to provide data for NAM validation in the short term. Therefore, it is worth investing resources for potential updates to existing standard test guidelines used in the laboratory as well as addressing the need for clear guidance on the conduct of field studies. Herein, we review the potential for improving standard in vivo test methods and for advancing the use of field studies in wildlife risk assessment, as these tools will be needed in the foreseeable future. Integr Environ Assess Manag 2024;20:699-724. © 2023 His Majesty the King in Right of Canada and The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Reproduced with the permission of the Minister of Environment and Climate Change Canada. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
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OBJECTIVE: Emergency department thoracotomy (EDT) is an uncommon but potentially lifesaving procedure that warrants familiarity with anatomy, instruments, and indications necessary for completion. To address this need, we developed a low-cost EDT trainer. The primary objective of this study was to compare the effectiveness of a low-cost EDT trainer to teach emergency department thoracotomy with a discussion-based teaching session. Secondary objective was to study the face validity of the low-cost EDT trainer. DESIGN: A prospective 2-phase randomized control study was conducted. Participants were randomly divided into two groups. In phase one, baseline medical knowledge for both groups was assessed using a multiple-choice question pretest. In Group 1, each participant was taught EDT using a one-on-one discussion with a trauma surgeon, whereas Group 2 used the EDT trainer and debriefing for training. In phase 2 (1 month later), all participants completed a knowledge retention test and performed a videoed EDT using our EDT trainer, the video recordings were later reviewed by content experts blinded to the study participants using a checklist with a maximum score of 22. The participants also completed a reaction survey at the end of phase 2 of the study. SETTING: OhioHealth Riverside Methodist Hospital, an urban tertiary care academic hospital in Columbus, Ohio. PARTICIPANTS: Nine senior surgery residents from training years 3 to 5. RESULTS: The mean score for the performance of the procedure for the simulation-based (Group 2) was significantly higher than that of the discussion-based (Group 1) (Rater 1: 21.2 ± 0.8 vs. 19.0 ± 2.0, pâ¯=â¯0.05, Rater 2: 20.4 ± 1.5 vs. 18.3±1.0, pâ¯=â¯0.04). Group 2 also was quicker than Group 1 in deciding to start the procedure by approximately 56 seconds. When comparing the mean pretest knowledge score to the mean knowledge retention score 30 days after training, the discussion-based group improved from 58.33% to 81.25% (pâ¯=â¯0.01); the simulation-trained group's scores remained at 68.33%. All the participants agreed or strongly agreed that the simulator provided a realistic opportunity to perform EDT and improved their confidence. CONCLUSIONS: The results of this pilot study support our hypothesis that using a low-cost EDT trainer effectively improves general surgery residents' confidence and procedural skills scores in a simulated environment. Further training with low-cost simulators may provide surgical residents with deliberate practice opportunities and improve performance when learning low-frequency procedures.
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Cirugía General , Internado y Residencia , Humanos , Toracotomía/educación , Proyectos Piloto , Estudios Prospectivos , Servicio de Urgencia en Hospital , Competencia Clínica , Cirugía General/educaciónRESUMEN
Despite advances in toxicity testing and the development of new approach methodologies (NAMs) for hazard assessment, the ecological risk assessment (ERA) framework for terrestrial wildlife (i.e., air-breathing amphibians, reptiles, birds, and mammals) has remained unchanged for decades. While survival, growth, and reproductive endpoints derived from whole-animal toxicity tests are central to hazard assessment, nonstandard measures of biological effects at multiple levels of biological organization (e.g., molecular, cellular, tissue, organ, organism, population, community, ecosystem) have the potential to enhance the relevance of prospective and retrospective wildlife ERAs. Other factors (e.g., indirect effects of contaminants on food supplies and infectious disease processes) are influenced by toxicants at individual, population, and community levels, and need to be factored into chemically based risk assessments to enhance the "eco" component of ERAs. Regulatory and logistical challenges often relegate such nonstandard endpoints and indirect effects to postregistration evaluations of pesticides and industrial chemicals and contaminated site evaluations. While NAMs are being developed, to date, their applications in ERAs focused on wildlife have been limited. No single magic tool or model will address all uncertainties in hazard assessment. Modernizing wildlife ERAs will likely entail combinations of laboratory- and field-derived data at multiple levels of biological organization, knowledge collection solutions (e.g., systematic review, adverse outcome pathway frameworks), and inferential methods that facilitate integrations and risk estimations focused on species, populations, interspecific extrapolations, and ecosystem services modeling, with less dependence on whole-animal data and simple hazard ratios. Integr Environ Assess Manag 2024;20:725-748. © 2023 His Majesty the King in Right of Canada and The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Reproduced with the permission of the Minister of Environment and Climate Change Canada. This article has been contributed to by US Government employees and their work is in the public domain in the USA.
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Birds can bioaccumulate persistent contaminants, and maternal transfer to eggs may expose embryos to concentrations sufficient to cause adverse effects during sensitive early-life stages. However, using tissue residue concentrations alone to infer whether contaminant effects are occurring suffers from uncertainty, and efficient, sensitive biomarkers remain limited in wildlife. We studied relationships between whole embryo contaminant concentrations (total mercury, organochlorine pesticides, perfluoroalkyl substances, polychlorinated biphenyls, and halogenated flame retardants) together with mRNA expression in embryonic liver tissue from a Pacific Ocean seabird, the rhinoceros auklet (Cerorhinca monocerata). Fresh eggs were collected, incubated under controlled conditions, and from the pre-hatch embryo, hepatic RNA was extracted for qPCR array analysis to measure gene expression (2-∆Cq), while the remaining embryo was analyzed for contaminant residues. Contaminant and gene expression data were assessed with a combination of multivariate approaches and linear models. Results indicated correlations between embryonic total mercury and several genes such as sepp1, which encodes selenoprotein P. Correlation between the biotransformation gene cyp1a4 and the C7 perfluoroalkyl carboxylic acid PFHpA was also evident. This study demonstrates that egg collection from free-living populations for contaminant biomonitoring programs can relate chemical residues to in ovo mRNA gene expression effects in embryo hepatic tissue.
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Charadriiformes , Mercurio , Bifenilos Policlorados , Animales , Monitoreo Biológico , ARN Mensajero/metabolismo , Bifenilos Policlorados/análisis , Aves/metabolismo , Hígado/química , Charadriiformes/metabolismo , Mercurio/análisis , Expresión Génica , Monitoreo del AmbienteRESUMEN
COVID-19 is an ongoing, global pandemic caused by the novel, highly infectious SARS-CoV-2 virus. Efforts to mitigate the effects of SARS-CoV-2, such as mass vaccination and development of monoclonal therapeutics, require precise measurements of correlative, functional neutralizing antibodies that block virus infection. The development of rapid, safe, and easy-to-use neutralization assays is essential for faster diagnosis and treatment. Here, we developed a vesicular stomatitis virus (VSV)-based neutralization assay with two readout methods, imaging and flow cytometry, that were capable of quantifying varying degrees of neutralization in patient serum samples. We tested two different spike-pseudoviruses and conducted a time-course assay at multiple multiplicities of infection (MOIs) to optimize the assay workflow. The results of this assay correlate with the results of previously developed serology and surrogate neutralization assays. The two pseudovirus readout methods produced similar values of 50% neutralization titer values. Harvest-free in situ readouts for live-cell imaging and high-throughput analysis results for flow cytometry can provide unique capabilities for fast evaluation of neutralization, which is critical for the mitigation of future pandemics.
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COVID-19 , SARS-CoV-2 , Humanos , Citometría de Flujo , Anticuerpos Antivirales , Pruebas de Neutralización/métodos , Anticuerpos NeutralizantesRESUMEN
We investigated the trophic magnification potential of perfluoroalkyl substances (PFAS) in a terrestrial food web by using a chemical activity-based approach, which involved normalizing concentrations of PFAS in biota to their relative biochemical composition in order to provide a thermodynamically accurate basis for comparing concentrations of PFAS in biota. Samples of hawk eggs, songbird tissues, and invertebrates were collected and analyzed for concentrations of 18 perfluoroalkyl acids (PFAAs) and for polar lipid, neutral lipid, total protein, albumin, and water content. Estimated mass fractions of PFCA C8-C11 and PFSA C4-C8 predominantly occurred in albumin within biota samples from the food web with smaller estimated fractions in polar lipids > structural proteins > neutral lipids and insignificant amounts in water. Estimated mass fractions of longer-chained PFAS (i.e., C12-C16) mainly occurred in polar lipids with smaller estimated fractions in albumin > structural proteins > neutral lipids > and water. Chemical activity-based TMFs indicated that PFNA, PFDA, PFUdA, PFDoA, PFTrDA, PFTeDA, PFOS, and PFDS biomagnified in the food web; PFOA, PFHxDA, and PFHxS did not appear to biomagnify; and PFBS biodiluted. Chemical activity-based TMFs for PFCA C8-C11 and PFSA C4-C8 were in good agreement with corresponding TMFs derived with concentrations normalized to only total protein in biota, suggesting that concentrations normalized to total protein may be appropriate proxies of chemical activity-based TMFs for PFAS, which predominantly partition to albumin. Similarly, TMFs derived with concentrations normalized to albumin may be suitable proxies of chemical activity-based TMFs for longer-chained PFAS, which predominantly partition to polar lipids.
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Fluorocarburos , Cadena Alimentaria , Animales , Aves , Albúminas , Agua , LípidosRESUMEN
Whether perfluoroalkyl sulfonates (PFSAs) and perfluoroalkyl carboxylates (PFCAs) are responding to legislative restrictions and showing decreasing trends in top marine predators that range across the eastern North Pacific Ocean is unclear. Here, we examined longer-term temporal trends (1973-2019) of 4 PFSAs and 13 PFCAs, as well stable isotopes of δ13C and δ15N, in the eggs of 4 seabird species sampled along a nearshore-offshore gradient; double-crested cormorants (Nannopterum auritum), pelagic cormorants (Urile pelagicus), rhinoceros auklets (Cerorhinca monocerata), and Leach's storm-petrels (Hydrobates leucorhous) from the Pacific coast of British Columbia, Canada. PFOS was the most abundant PFSA (79-94%) detected in all eggs regardless of colony and year, with the highest concentrations, on average, measured in auklet eggs (mean = 58 ng g-1, range = 11-286 ng g-1 ww). Perfluoroundecanoic acid (PFUdA) and perfluorotridecanoic acid (PFTriDA) were the dominant long-chain PFCAs (≥30% combined). The majority of PFSAs (including PFOS) are statistically declining (p < 0.001) in the eggs of all 4 species with PFOS half-lives ranging from 2.6 to 7.8 years. Concentrations of long-chain PFCAs exhibited a trajectory comprised of linear increases and second-order declines, suggesting that the rate of uptake of PFCAs is slowing or leveling off. These trends are consistent with the voluntarily ceased production of PFSAs by 3M circa 2000-2003 and are among the first from the northeast Pacific to indicate a positive response to several regulations and restrictions on PFCAs from facility emissions and product content.
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Ácidos Alcanesulfónicos , Charadriiformes , Fluorocarburos , Animales , Monitoreo del Ambiente , Fluorocarburos/análisis , Aves , Colombia Británica , Alcanosulfonatos , Ácidos Carboxílicos , Ácidos Alcanesulfónicos/análisisRESUMEN
Introduction Telehealth visits (TH) have become an important pillar of healthcare delivery during the COVID pandemic. No-shows (NS) may result in delays in clinical care and in lost revenue. Understanding the factors associated with NS may help providers take measures to decrease the frequency and impact of NS in their clinics. We aim to study the demographic and clinical diagnoses associated with NS to ambulatory telehealth neurology visits. Methods We conducted a retrospective chart review of all telehealth video visits (THV) in our healthcare system from 1/1/2021 to 5/1/2021 (cross-sectional study). All patients at or above 18 years of age who either had a completed visit (CV) or had an NS for their neurology ambulatory THV were included. Patients having missing demographic variables and not meeting the ICD-10 primary diagnosis codes were excluded. Demographic factors and ICD-10 primary diagnosis codes were retrieved. NS and CV groups were compared using independent samples t-tests and chi-square tests as appropriate. Multivariate regression, with backward elimination, was conducted to identify pertinent variables. Results Our search resulted in 4,670 unique THV encounters out of which 428 (9.2%) were NS and 4,242 (90.8%) were CV. Multivariate regression with backward elimination showed that the odds of NS were higher with a self-identified non-Caucasian race OR = 1.65 (95%, CI: 1.28-2.14), possessing Medicaid insurance OR = 1.81 (95%, CI: 1.54-2.12) and with primary diagnoses of sleep disorders OR = 10.87 (95%, CI: 5.55-39.84), gait abnormalities (OR = 3.63 (95%, CI: 1.81-7.27), and back/radicular pain OR = 5.62 (95%, CI: 2.84-11.10). Being married was associated with CVs OR = 0.74 (95%, CI: 0.59-0.91) as well as primary diagnoses of multiple sclerosis OR = 0.24 (95%, CI: 0.13-0.44) and movement disorders OR = 0.41 (95%, CI: 0.25-0.68). Conclusion Demographic factors, such as self-identified race, insurance status, and primary neurological diagnosis codes, can be helpful to predict an NS to neurology THs. This data can be used to warn providers regarding the risk of NS.