RESUMO
The outbreak of e-cigarette or vaping use-associated lung injury (EVALI) in the United States in 2019 led to a total of 2807 hospitalizations with 68 deaths. While the exact causes of this vaping-related lung illness are still being debated, laboratory analyses of products from victims of EVALI have shown that vitamin E acetate (VEA), an additive in some tetrahydrocannabinol (THC)-containing products, is strongly linked to the EVALI outbreak. Because of its similar appearance and viscosity to pure THC oil, VEA was used as a diluent agent in cannabis oils in illicit markets. A potential mechanism for EVALI may involve VEA's thermal decomposition product, ketene, a highly poisonous gas, being generated under vaping conditions. In this study, a novel approach was developed to evaluate ketene production from VEA vaping under measurable temperature conditions in real-world devices. Ketene in generated aerosols was captured by two different chemical agents and analyzed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography with tandem mass spectrometry (LC-MS/MS). The LC-MS/MS method takes advantage of the high sensitivity and specificity of tandem mass spectrometry and appears to be more suitable than GC-MS for the analysis of large batches of samples. Our results confirmed the formation of ketene when VEA was vaped. The production of ketene increased with repeat puffs and showed a correlation to temperatures (200 to 500 °C) measured within vaping devices. Device battery power strength, which affects the heating temperature, plays an important role in ketene formation. In addition to ketene, the organic oxidant duroquinone was also obtained as another thermal degradation product of VEA. Ketene was not detected when vitamin E was vaped under the same conditions, confirming the importance of the acetate group for its generation.
Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Etilenos , Cetonas , Vaping , Vaping/efeitos adversos , Cetonas/química , Cetonas/análise , Etilenos/química , Humanos , Saúde Pública , Vitamina E/química , Vitamina E/análise , Lesão Pulmonar/etiologia , Lesão Pulmonar/induzido quimicamente , Cromatografia Gasosa-Espectrometria de MassasRESUMO
Minimization of airborne virus transmission has become increasingly important due to pandemic and endemic infectious respiratory diseases. Physical distancing is a frequently advocated control measure, but the proximity-based transmission it is intended to control is challenging to incorporate into generalized, ventilation-based models. We utilize a size-dependent aerosol release model with turbulent dispersion to assess the impact of direct, near-field transport in conjunction with changes in ventilation, exposure duration, exhalation/inhalation rates, and masks. We demonstrate this model on indoor and outdoor scenarios to estimate the relative impacts on infection risk. The model can be expressed as a product of six multiplicative factors that may be used to identify opportunities for risk reduction. The additive nature of the short-range (proximity) and long-range (background) transmission components of the aerosol transport factor implies that they must be minimized simultaneously. Indoor simulations showed that close physical distances attenuated the impact of most other risk reduction factors. Increasing ventilation resulted in a 17-fold risk decrease at further physical distances but only a 6-fold decrease at shorter distances. Distance, emission rate, and duration also had large impacts on risk (11-65-fold), while air direction and inhalation rate had lower risk impacts (3-4-fold range). Surgical mask and respirator models predicted higher maximum risk impacts (33- and 280-fold, respectively) than cloth masks (4-fold). Most simulations showed decreasing risk at distances > 1-2 m (3-6 ft). The risk benefit of maintaining 2-m distance vs. 1 m depended substantially on the environmental turbulence and ventilation rate. Outdoors, long-range transmission was negligible and short-range transmission was the primary determinant of risk. Temporary passing events increased risk by up to 50 times at very slow walking speeds and close passing distances, but the relative risks outdoors were still much lower than indoors. The current model assumes turbulent dispersion typical of a given room size and ventilation rate. However, calm environments or confined airflows may increase transmission risks beyond levels predicted with this turbulent model.
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COVID-19 , Distanciamento Físico , Aerossóis , Humanos , Pandemias , SARS-CoV-2RESUMO
Microplastics were extracted from freshwater sport fish stomachs containing substantial biomass and identified using optical microscopy, scanning electron microscopy plus energy-dispersive X-ray spectroscopy (SEM/EDS), and Fourier transform infrared (FTIR) micro-spectroscopy with automated spectral mapping. An extraction method is presented that uses a negatively pressurized sieve stack and purified water to preserve plastic surface characteristics and any adsorbed persistent organic pollutants (POPs). This nondestructive extraction method for large predators' stomachs enables multiple trophic-level studies from one fish sampling event and provides other dietary and behavioral data. FTIR-identified microplastics 50-1500 µm, including polyethylene (two with plastic additive POPs), styrene acrylonitrile, polystyrene, and nylon and polyethylene terephthalate fibers 10-50 µm wide. SEM/EDS revealed characteristic surface weathering on the plastic surfaces. The nylon fibers appear to be from human fishing activities, suggesting options for management. Some particles visually identified as potential plastics were revealed by micro-spectroscopy to be mineralized, natural polyamide proteins, or nonplastic shell pieces. A low-cost, reflective sample preparation method with stable particle mounting was developed to enable automated mapping, improved FTIR throughput, and lower detection size limit. This study yielded 37 intact prey items set aside for future analyses.
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Peixes , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Água Doce , Microplásticos , Plásticos , Espectroscopia de Infravermelho com Transformada de Fourier , EstômagoAssuntos
Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/epidemiologia , Sistemas Eletrônicos de Liberação de Nicotina/estatística & dados numéricos , Etilenos/efeitos adversos , Cetonas/efeitos adversos , Vaping/efeitos adversos , Lesão Pulmonar Aguda/fisiopatologia , Feminino , Humanos , Incidência , Masculino , Medição de Risco , Estados UnidosRESUMO
PURPOSE: The objective of this study was to understand at what level of the Autonomous Pharmacy Framework facilities are operating, in terms of the current state of data collection and analysis in the medication-use process, and to gather insights about systems integration and automation use. METHODS: The Autonomous Pharmacy Advisory Board, a group of chief pharmacy officers and operational leaders, developed a self-assessment instrument based on the previously published Autonomous Pharmacy Framework, made the self-assessment instrument available via the internet, and reviewed respondents' self-reported results. The data collection period for the survey started in March of 2021 and ended in January of 2023. RESULTS: A total of 119 facility-level self-assessments were completed and analyzed. On a scale of 1 to 5, where 1 represented little or no data-driven automation with lots of manual tasks and 5 represented the utmost data-driven automation with few manual tasks, the average overall facility-level score was 2.77 (range, 1.38-4.41). Results revealed slight variance by facility bed capacity. Much more variation was found in the degrees to which individual facilities have automated core processes like inventory management, intravenous medication preparation, and financial reporting. CONCLUSION: As a baseline, this automation-focused facility self-assessment suggests that for essentially all health-system pharmacy facilities and their larger organizations, a substantial body of work needs to be done to further develop and upgrade technology and practice in tandem, greatly expand data collection and analysis, and thereby achieve better operational, financial, and clinical outcomes. Significant advancements are needed to arrive at the highly reliable, highly automated, data-driven medication-use process involving few repetitive manual tasks envisioned in the Autonomous Pharmacy Framework.
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Farmácias , Serviço de Farmácia Hospitalar , Farmácia , Humanos , Autoavaliação (Psicologia) , AutomaçãoRESUMO
We present correlated application of two micro-analytical techniques: scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS) for the non-invasive characterization and molecular identification of flame retardants (FRs) in environmental dusts and consumer products. The SEM/EDS-RMS technique offers correlated, morphological, molecular, spatial distribution and semi-quantitative elemental concentration information at the individual particle level with micrometer spatial resolution and minimal sample preparation. The presented methodology uses SEM/EDS analyses for rapid detection of particles containing FR specific elements as potential indicators of FR presence in a sample followed by correlated RMS analyses of the same particles for characterization of the FR sub-regions and surrounding matrices. The spatially resolved characterization enabled by this approach provides insights into the distributional heterogeneity as well as potential transfer and exposure mechanisms for FRs in the environment that is typically not available through traditional FR analysis. We have used this methodology to reveal a heterogeneous distribution of highly concentrated deca-BDE particles in environmental dust, sometimes in association with identifiable consumer materials. The observed coexistence of deca-BDE with consumer material in dust is strongly indicative of its release into the environment via weathering/abrasion of consumer products. Ingestion of such enriched FR particles in dust represents a potential for instantaneous exposure to high FR concentrations. Therefore, correlated SEM/RMS analysis offers a novel investigative tool for addressing an area of important environmental concern.
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Meio Ambiente , Poluentes Ambientais/análise , Retardadores de Chama/análise , Microscopia Eletrônica/métodos , Microtecnologia/métodos , Análise Espectral Raman/métodos , Qualidade de Produtos para o Consumidor , Poluentes Ambientais/químicaRESUMO
Asbestos is a known human carcinogen, and recent regulation in California limits asbestiform fibers in brakes to trace levels beginning in 2014, although there is no corresponding federal requirement. In order to gauge the current prevalence of asbestos use in automotive brake applications, the California Air Resources Board tested brake linings from 137 light- and medium-duty vehicles and 54 heavy-duty vehicles. Only about 3% of the light- and medium-duty vehicle brake linings contained chrysotile asbestos. All of those brake linings were drum-type shoes, which are generally being phased out. No asbestos was found in low mileage vehicles presumed to have their original stock linings from the vehicle manufacturer. Additionally, no asbestos was found in the heavy-duty vehicle brake shoe linings sampled. Given the small percentage of vehicle brake linings with asbestos observed, it appears that the prior federal ban that was subsequently overturned, in combination with a threat of litigation, has reduced asbestos use in brake linings. However, our study was limited in scope and without a national ban, the current and future prevalence of asbestos in brakes is uncertain, suggesting the need for continued monitoring of materials released as toxic air contaminants in normal braking operations.
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Amianto/análise , Poluição Ambiental/prevenção & controle , Veículos Automotores , Material Particulado/análise , California , Poluição Ambiental/legislação & jurisprudência , Humanos , Microscopia , Inquéritos e QuestionáriosRESUMO
This work compares relative mask inhalation protection against a range of airborne particle sizes that the general public may encounter, including infectious particles, wildfire smoke and ash, and allergenic fungal and plant particles. Several mask types available to the public were modeled with respirable fraction deposition. Best-case collection efficiencies for cloth, surgical, and respirator masks were predicted to be lowest (0.3, 0.6, and 0.8, respectively) for particle types with dominant sub-micrometer modes (wildfire smoke and human-emitted bronchial particles). Conversely, all mask types were predicted to achieve good collection efficiency (up to ~1.0) for the largest-sized particle types, including pollen grains, some fungal spores, and wildfire ash. Polydisperse infectious particles were predicted to be captured by masks with efficiencies of 0.3-1.0 depending on the pathogen size distribution and the type of mask used. Viruses aerosolized orally are predicted to be captured efficiently by all mask types, while those aerosolized from bronchiolar or laryngeal-tracheal sites are captured with much lower efficiency by surgical and cloth masks. The predicted efficiencies changed very little when extrathoracic deposition was included (inhalable rather than respirable fraction) or when very large (100 µm) particles were neglected. Actual mask fit and usage will determine protection levels in practice, but the relative comparisons in this work can inform mask guidance for different inhalation hazards, including particles generated by yard work, wildfires, and infections.
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Dispositivos de Proteção Respiratória , Humanos , Máscaras , Fumaça , Alérgenos , Tamanho da Partícula , AerossóisRESUMO
The need for improved microplastic (MP) data accuracy has been widely reported, but MP precision issues have been investigated less thoroughly. This work demonstrates how initial and continuing assessments of a laboratory's analytical precision can be used for establishing laboratory repeatability for MP analyses. These precision estimates can be reported along with MP results to ensure their quality and compare them meaningfully to other data. Re-analyses of reference MP samples can be used to assess and compare precision between different laboratories. A multi-lab precision exercise was demonstrated using infrared (IR) standard test methods performed on reference samples consisting of low-concentration MP spikes in both clean water and wastewater matrices. Each lab repeated their IR analyses 7 times and calculated relative standard deviations (RSD) for each detected polymer type using a standardized template. All labs' MP methods yielded generally repeatable results, though RSDs were consistently higher for lower MP counts. The reported range of total MP counts per sample was 8-33 particles, and the observed RSDs were 0.1-0.6. These RSDs were the same or lower than the expected imprecision due to random (Poisson) counting error alone, suggesting that these automated methods did not contribute any additional variability, and had slightly better reproducibility than expected for independent recounts. The wastewater matrix exhibited numerous interfering particles but did not yield more variability than the clean water matrix. The low-count design is a worst case for precision but is appropriate for some real-world sample concentrations. In practice, labs could generate separate references for precision assessment at multiple MP ranges (e.g., high, medium, and low.) The RSDs obtained from this data can be used to generate QC charts, detect changes in analyst performance, compare to Poisson error to identify additional sources of imprecision, and determine target filtration and instrumental parameters for MP analyses.
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Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Plásticos/análise , Reprodutibilidade dos Testes , Águas Residuárias/análise , Água/análise , Poluentes Químicos da Água/análiseRESUMO
Public complaints have raised concerns that some mattresses in the current marketplace may be potential sources of airborne fiberglass. Although mattress foam is often marketed as chemical-free, their cover compositions are not as well understood by the general public. To fill these basic information gaps, the covers of four newly purchased mattresses were sampled and analyzed using polarized light microscopy, SEM-EDS, and FTIR microspectroscopy. Two of the mattress covers contained over 50% fiberglass in their inner sock layers. Up to 1% of the fiberglass had migrated to adjacent fabric layers, representing a potential risk of consumer exposure if the zipper on the outer cover is opened. The observed fiberglass fragments had calculated aerodynamic diameters ranging between 30 and 50 µm, suggesting they are potentially inhalable into the nose, mouth, and throat, but are likely too large to penetrate deeper into the lungs. No fiberglass was observed on the brand new mattresses' outer surfaces. Synthetic fibers also present in the sock layers were consistent with flame resistant modacrylic containing vinyl chloride and antimony. The use of fiberglass and other chemicals in mattress covers poses a potential health risk if these materials are not adequately contained. The apparent non-inclusion of mattress covers in chemical-free certifications suggests that further improvements are needed in mattress labeling and education of consumers.
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Antimônio , Leitos , VidroRESUMO
Three acute cardiovascular events within a 4-month period among drivers at an indoor go-kart arena prompted a visit to assess the magnitude of potentially hazardous air pollutant levels within the facility and help identify control measures. Carbon monoxide (CO) and particulate matter with aerodynamic diameters < 2.5 microm (PM2.5) were measured with personal, continuous-reading instruments to capture their spatial and temporal variability. Average driver and track CO levels during the sampling visit were comparable to state standards for worker exposures and exceeded some health-based guidelines. Average PM2.5 levels were low compared with regulatory standards, but transient PM2.5 peaks of unknown health impact were observed. Driver exposures were modestly but significantly higher than track concentrations measured by stationary monitors and substantially higher than outdoor concentrations. Driver exposures were partitioned into three components, attributed to (1) outdoor pollutants that were drawn unfiltered into the facility, (2) the persistent track cloud from previous races, and (3) proximity to the exhausts of other go-karts while driving in a race. Track cloud and tailpipe proximity components were the dominant contributors to driver CO exposure. The track cloud component lagged the number of go-karts on the track by 10-15 min. The dominant contributor to driver PM2.5 exposure was either the track cloud or outdoor component, depending on how many go-karts were racing simultaneously on the track. Transient spikes in PM2.5 were caused by proximity to other karts' tailpipes during passing events. Recommended methods for decreasing the track cloud component include modifying the ventilation system, race schedules, and number of go-karts racing simultaneously. The tailpipe proximity component can be reduced only by modifying go-kart exhausts or engines. This work represents a brief, limited sampling visit to a single facility, but it demonstrates the levels that are possible on a fairly high-usage afternoon. Future studies should be conducted to assess representative go-kart facility exposures at multiple facilities on multiple days.
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Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/análise , Monóxido de Carbono/análise , Exposição por Inalação/análise , Material Particulado/análise , Emissões de Veículos/análise , Condução de Veículo , Monóxido de Carbono/normas , Monitoramento Ambiental , Humanos , Tamanho da Partícula , Material Particulado/normas , Recreação , Local de TrabalhoRESUMO
BACKGROUND: Identifying the functional materials inside vaping devices can help inform efforts to understand risk. While nicotine E-cigarette components and metals have been characterized in several previous studies, the internal component compositions of tetrahydrocannabinol (THC) cartridge designs are not as well known. The 2019-20 e-cigarette or vaping product use associated lung injury (EVALI) outbreak has been associated with THC devices containing vitamin E acetate (VEA), possibly mediated by chemical reactions with internal cartridge components and high filament temperatures. METHODS: We investigate the composition and internal components of 2019 EVALI patient-associated THC vaping devices compared to other THC and nicotine devices from 2016-19, specifically the metal, ceramic, and polymer components likely to be exposed to heat. To do this, we have disassembled forty-eight components from eight used and unused vaping devices under a microscope and analyzed them using X-ray fluorescence, scanning electron microscopy, and Fourier-transform infrared micro-spectroscopy. CONCLUSIONS: The two THC cartridges used by EVALI patients exhibited evidence of localized high temperatures, including charring of the ceramic heating elements and damaged wire surfaces. The newer THC cartridges possessed more ceramic and polymer insulation than older THC or nicotine devices. The combination of ceramics, metals, and high temperatures in newer THC cartridges is consistent with conditions hypothesized to produce VEA reactions during vaping. Nickel and chromium components were detected in all devices, and others contained copper, lead, tin, gold, silicon-rich rubbers, or fluorinated microplastics. These components have the potential to thermally degrade and volatilize if heated sufficiently. These findings do not imply that harmful exposures would occur under all usage conditions, and are most relevant to harm reduction efforts based on avoiding higher internal temperatures. This study was limited to a small sample of cartridges obtained from investigations. Future work should test more device types and internal temperatures under controlled usage conditions.
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Dronabinol/efeitos adversos , Sistemas Eletrônicos de Liberação de Nicotina , Lesão Pulmonar/patologia , Nicotina/química , Canabinoides/toxicidade , Cerâmica/efeitos adversos , Cerâmica/química , Surtos de Doenças , Dronabinol/química , Temperatura Alta/efeitos adversos , Humanos , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/epidemiologia , Microscopia Eletrônica de Varredura , Nicotina/efeitos adversos , Plásticos/efeitos adversos , Polímeros/efeitos adversos , Polímeros/química , Borracha/efeitos adversos , Borracha/química , Vaping/fisiopatologiaRESUMO
A new protocol for the extraction of microplastic is proposed and demonstrated which combines dissection, ultrasonication, and filtration with chemical dissolution in order to estimate microplastic contamination in fish or other samples with significant biomass. This protocol enables initial characterization of the sample through dissection followed by chemical dissolution to isolate polymer debris while minimizing analytical uncertainties and maintaining microplastic particle integrity. The extraction method begins with dissection and inspection of the stomach contents, followed by pulsed ultrasonic extraction to remove the majority of biomass and surface contaminants. Subsequent chemical dissolution of the extracted contents using KOH and HCl removes any remaining biomass and inorganic interferences. Incorporating chemical dissolution post-extraction minimizes the overall biomass subjected to dissolution, thereby enabling faster processing and subsequently a cleaner sample compared to methods involving digestion of the entire organism. Furthermore, the chemical dissolution step enables direct filter analysis for microplastics, thereby minimizing the potential loss of microplastic particles associated with manual particle transfer. Hence, the microplastic extraction method presented here is suitable for the extraction and identification of small (>20 µm) and potentially brittle microplastic.
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Microplásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Plásticos , Solubilidade , Poluentes Químicos da Água/análiseRESUMO
Importance: Since August 2019, more than 2700 patients have been hospitalized with e-cigarette, or vaping, product use-associated lung injury (EVALI) across the United States. This report describes the outbreak in California, a state with one of the highest case counts and with a legal adult-use (recreational) cannabis market. Objective: To present clinical characteristics and vaping product exposures of patients with EVALI in California. Design, Setting, and Participants: Case series describing epidemiologic and laboratory data from 160 hospitalized patients with EVALI reported to the California Department of Public Health by local health departments, who received reports from treating clinicians, from August 7 through November 8, 2019. Exposures: Standardized patient interviews were conducted to assess vaping products used, frequency of use, and method of product acquisition. Vaping products provided by a subset of patients were tested for active ingredients and other substances. Main Outcomes and Measures: Demographic and clinical characteristics, level of care, and outcomes of hospitalization were obtained from medical record review. Results: Among 160 patients with EVALI, 99 (62%) were male, and the median age was 27 years (range, 14-70 years). Of 156 patients with data available, 71 (46%) were admitted to an intensive care unit, and 46 (29%) required mechanical ventilation. Four in-hospital deaths occurred. Of 86 patients interviewed, 71 (83%) reported vaping tetrahydrocannabinol (THC)-containing products, 36 (43%) cannabidiol (CBD)-containing products, and 39 (47%) nicotine-containing products. Sixty-five of 87 (75%) THC-containing products were reported as obtained from informal sources, such as friends, acquaintances, or unlicensed retailers. Of 87 vaping products tested from 24 patients, 49 (56%) contained THC. Vitamin E or vitamin E acetate was found in 41 (84%) of the THC-containing products and no nicotine products. Conclusions and Relevance: Patients' clinical outcomes and vaping behaviors, including predominant use of THC-containing products from informal sources, are similar to those reported by other states, despite California's legal recreational cannabis market. While most THC products tested contained vitamin E or vitamin E acetate, other underlying cause(s) of injury remain possible. The California Department of Public Health recommends that individuals refrain from using any vaping or e-cigarette products, particularly THC-containing products from informal sources, while this investigation is ongoing.
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Sistemas Eletrônicos de Liberação de Nicotina , Hospitalização/tendências , Lesão Pulmonar/induzido quimicamente , Saúde Pública , Vaping/efeitos adversos , Adolescente , Adulto , Idoso , California/epidemiologia , Feminino , Humanos , Incidência , Lesão Pulmonar/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Adulto JovemRESUMO
BACKGROUND: Because of the overwhelming benefit of thrombectomy for highly selected trial patients with large vessel occlusion (LVO), some trial-ineligible patients are being treated in practice. OBJECTIVE: To determine the safety and efficacy of thrombectomy in DAWN/DEFUSE-3-ineligible patients. METHODS: Using a multicenter prospective observational study of consecutive patients with anterior circulation LVO who underwent late thrombectomy, we compared symptomatic intracerebral hemorrhage (sICH) and good outcome (90-d mRS 0-2) among DAWN/DEFUSE-3-ineligible patients to trial-eligible patients and to untreated DAWN/DEFUSE-3 controls. RESULTS: Ninety-eight patients had perfusion imaging and underwent thrombectomy >6 h; 46 (47%) were trial ineligible (41% M2 occlusions, 39% mild deficits, 28% ASPECTS <6). In multivariable regression, the odds of a good outcome (aOR 0.76, 95% CI 0.49-1.19) and sICH (aOR 3.33, 95% CI 0.42-26.12) were not different among trial-ineligible vs eligible patients. Patients with mild deficits were more likely to achieve a good outcome (aOR 3.62, 95% CI 1.48-8.86) and less sICH (0% vs 10%, P = .16), whereas patients with ASPECTS <6 had poorer outcomes (aOR 0.14, 95% CI 0.05-0.44) and more sICH (aOR 24, 95% CI 5.7-103). Compared to untreated DAWN/DEFUSE-3 controls, trial-ineligible patients had more sICH (13%BEST vs 3%DAWN [P = .02] vs 4%DEFUSE [P = .05]), but were more likely to achieve a good outcome at 90 d (36%BEST vs 13%DAWN [P < .01] vs 17%DEFUSE [P = .01]). CONCLUSION: Thrombectomy is used in practice for some patients ineligible for the DAWN/DEFUSE-3 trials with potentially favorable outcomes. Additional trials are needed to confirm the safety and efficacy of thrombectomy in broader populations, such as large core infarction and M2 occlusions.
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Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Trombectomia/tendências , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: The 2018 AHA guidelines recommend perfusion imaging to select patients with acute large vessel occlusion (LVO) for thrombectomy in the extended window. However, the relationship between noncontrast CT and CT perfusion imaging has not been sufficiently characterized >6 hours after last known normal (LKN). METHODS: From a multicenter prospective cohort of consecutive adults who underwent thrombectomy for anterior LVO 0-24 hours after LKN, we correlated baseline core volume (rCBF < 30%) and the Alberta Stroke Program Early CT Scale (ASPECTS) score. We compared perfusion findings between patients with an unfavorable ASPECTS (<6) against those with a favorable ASPECTS (≥6), and assessed findings over time. RESULTS: Of 485 enrolled patients, 177 met inclusion criteria (median age: 69 years, interquartile range [IQR: 57-81], 49% female, median ASPECTS 8 [IQR: 6-9], median core 10 cc [IQR: 0-30]). ASPECTS and core volume moderately correlated (r = -.37). A 0 cc core was observed in 54 (31%) patients, 70% of whom had ASPECTS <10. Of the 28 patients with ASPECTS <6, 3 (11%) had a 0 cc core. After adjustment for age and stroke severity, there was a lower ASPECTS for every 1 hour delay from LKN (cOR: 0.95, 95% confidence of interval [CI]: 0.91-1.00, P = .04). There was no difference in core (P = .51) or penumbra volumes (P = .87) across patients over time. CONCLUSIONS: In this multicenter prospective cohort of patients who underwent thrombectomy, one-third of patients had normal CTP core volumes despite nearly three quarters of patients showing ischemic changes on CT. This finding emphasizes the need to carefully assess both noncontrast and perfusion imaging when considering thrombectomy eligibility.
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Isquemia Encefálica/diagnóstico por imagem , Imagem de Perfusão/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Alberta , Pressão Sanguínea/fisiologia , Isquemia Encefálica/terapia , Procedimentos Endovasculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Trombectomia/métodosRESUMO
This article was migrated. The article was marked as recommended. Students have traditionally held a singular role in medical education - the learner. This narrow view neglects students unique perspective and ability to shape the future of medical education. In recognizing the need for deliberate leadership skill development and networking opportunities for medical student leaders, the American Medical Association (AMA) supported the first AMA Accelerating Change in Medical Education Student-Led Conference on Leadership in Medical Education. A planning committee of 19 students from seven medical schools collaborated to develop this conference, which took place on August 4-5, 2017 at the University of Michigan, Ann Arbor. The primary goal of the conference was for students to learn about leadership skills, connect with other student leaders, feel empowered to lead change, and continue to lead from their roles as students. Attendees participated in a variety of workshops and presentations focused on developing practical leadership skills. In addition, students formed multi-institutional teams to participate on in the MedEd Impact Challenge, attempting to address issues in medical education such as leadership curriculum development, wellness, and culture change. Post-conference surveys showed an overwhelming majority of students connected with other student leaders, shared ideas, developed collaborations, and felt empowered to enact change. Looking forward, we believe that similar student-led conferences focused on broadening the medical student role would provide avenues for positive change in medical education.
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Pacific Ocean trawl samples, stomach contents of laboratory-raised fish as well as fish from the subtropical gyres were analyzed by Raman micro-spectroscopy (RMS) to identify polymer residues and any detectable persistent organic pollutants (POP). The goal was to access specific molecular information at the individual particle level in order to identify polymer debris in the natural environment. The identification process was aided by a laboratory generated automated fluorescence removal algorithm. Pacific Ocean trawl samples of plastic debris associated with fish collection sites were analyzed to determine the types of polymers commonly present. Subsequently, stomach contents of fish from these locations were analyzed for ingested polymer debris. Extraction of polymer debris from fish stomach using KOH versus ultrapure water were evaluated to determine the optimal method of extraction. Pulsed ultrasonic extraction in ultrapure water was determined to be the method of choice for extraction with minimal chemical intrusion. The Pacific Ocean trawl samples yielded primarily polyethylene (PE) and polypropylene (PP) particles >1 mm, PE being the most prevalent type. Additional microplastic residues (1 mm - 10 µm) extracted by filtration, included a polystyrene (PS) particle in addition to PE and PP. Flame retardant, deca-BDE was tentatively identified on some of the PP trawl particles. Polymer residues were also extracted from the stomachs of Atlantic and Pacific Ocean fish. Two types of polymer related debris were identified in the Atlantic Ocean fish: (1) polymer fragments and (2) fragments with combined polymer and fatty acid signatures. In terms of polymer fragments, only PE and PP were detected in the fish stomachs from both locations. A variety of particles were extracted from oceanic fish as potential plastic pieces based on optical examination. However, subsequent RMS examination identified them as various non-plastic fragments, highlighting the importance of chemical analysis in distinguishing between polymer and non-polymer residues.
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Monitoramento Ambiental , Conteúdo Gastrointestinal/química , Polímeros/análise , Resíduos/análise , Poluentes Químicos da Água/análise , Animais , Oceano Atlântico , Peixes , Oceanos e Mares , Oceano Pacífico , Plásticos/análise , Polietileno/análise , Poliestirenos/análise , Água do Mar/química , Análise Espectral Raman , Estômago/químicaRESUMO
In the present research, the potential of breath analysis by comprehensive two-dimensional gas chromatography coupled to mass spectrometry (GC×GC-MS) was investigated for the discrimination between healthy and infected mice. A pilot study employing a total of 16 animals was used to develop a method for breath analysis in a murine model for studying Mycobacterium tuberculosis complex (MTBC) using the M. bovis bacillus Calmette-Guérin. Breath was collected in Tedlar bags and concentrated onto thermal desorption tubes for subsequent analysis by GC×GC-MS. Immunological test and bacterial cell count in bronchoalveolar lavage fluid and mice lung homogenate confirmed the presence of bacteria in the infected group. From the GC×GC-MS analysis, 23 molecules were found to mainly drive the separation between control and infected mice and their tentative identification is provided.This study shows that the overall used methodology is able to differentiate breath between healthy and infected animals, and the information herein can be used to further develop the mouse breath model to study MTBC pathogenesis, evaluate pre-clinical drug regimen efficacy, and to further develop the concept of breath-based diagnostics.
Assuntos
Testes Respiratórios/métodos , Infecções por Mycobacterium/diagnóstico , Mycobacterium bovis/isolamento & purificação , Animais , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Cromatografia Gasosa-Espectrometria de Massas , Macrófagos/patologia , Masculino , Camundongos Endogâmicos C57BL , Infecções por Mycobacterium/microbiologia , Infecções por Mycobacterium/patologia , Neutrófilos/patologia , Projetos Piloto , Análise de Componente PrincipalRESUMO
In this pilot study, volatile molecules produced by cultures of Mycobacterium tuberculosis were evaluated to determine whether they could be used to discriminate between uninfected and M. tuberculosis-infected macaques. Thirty seven of the culture biomarkers were detectable in macaque breath and were shown to discriminate between uninfected and infected animals with an area under the curve (AUC) of 87%. An AUC of 98% was achieved when using the top 38 discriminatory molecules detectable in breath. We report two newly discovered volatile biomarkers, not previously associated with M. tuberculosis, that were selected in both our in vitro and in vivo discriminatory biomarker suites: 4-(1,1-dimethylpropyl)phenol and 4-ethyl-2,2,6,6-tetramethylheptane. Additionally, we report the detection of heptanal, a previously identified M. tuberculosis breath biomarker in humans, as an in vitro culture biomarker that was detected in every macaque breath sample analyzed, though not part of the in vivo discriminatory suite. This pilot study suggests that molecules from the headspace of M. tuberculosis culture show potential to translate as breath biomarkers for macaques infected with the same strain.