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A series of chloro-alkylammonium montmorillonites was produced by cation exchange from Na+-montmorillonite. Gas chromatographic data were obtained for light hydrocarbons and certain oxides of nitrogen. Surface area and X-ray powder diffraction studies were made on each organo-clay, making possible differentiation between possible chromatographic pathways. Adsorption of the gas molecules on the silicate sheet was determined to be the dominant chromatographic pathway for all gases studied.
The COVID-19 pandemic and subsequent social distancing guidelines and restrictions brought on changes in the everyday experiences of older adults. It is not clear, however, to what extent the pandemic has impacted the importance of everyday preferences for persons with cognitive impairment (CI) or the proxy ratings of those preferences. The sample of this study included 27 dyads of persons with CI and their care partners. The Preferences for Everyday Living Inventory was used to assess importance of preferences among persons with CI; care partners completed concurrent proxy assessments. Mixed random and fixed effects longitudinal models were used to evaluate changes in ratings and concordance levels between persons with CI and care partners prior to and during the COVID-19 pandemic. Persons with CI rated autonomous choice preferences as significantly more important during the COVID-19 pandemic than before; there was no association between the COVID-19 pandemic and change in other everyday preferences domains or discrepancy in proxy assessments of everyday preferences. Identifying avenues to support and provide for autonomy in the decision-making of older adults with CI may offer a way forward in mitigating the psychological and behavioral impacts of the COVID-19 pandemic in this population.
Agitation is a common complication of Alzheimer’s dementia (Agit-AD) associated with substantial morbidity, high healthcare service utilization, and adverse emotional and physical impact on care partners. There are currently no FDA-approved pharmacological treatments for Agit-AD. We present the study design and baseline data for an ongoing multisite, three-week, double-blind, placebo-controlled, randomized clinical trial of dronabinol (synthetic tetrahydrocannabinol [THC]), titrated to a dose of 10 mg daily, in 80 participants to examine the safety and efficacy of dronabinol as an adjunctive treatment for Agit-AD. Preliminary findings for 44 participants enrolled thus far show a predominately female, white sample with advanced cognitive impairment (Mini Mental Status Examination mean 7.8) and agitation (Neuropsychiatric Inventory-Clinician Agitation subscale mean 14.1). Adjustments to study design in light of the COVID-19 pandemic are described. Findings from this study will provide guidance for the clinical utility of dronabinol for Agit-AD. ClinicalTrials.gov Identifier: NCT02792257.
Pharmacogenomic testing has emerged to aid medication selection for patients with major depressive disorder (MDD) by identifying potential gene-drug interactions (GDI). Many pharmacogenomic tests are available with varying levels of supporting evidence, including direct-to-consumer and physician-ordered tests. We retrospectively evaluated the safety of using a physician-ordered combinatorial pharmacogenomic test (GeneSight) to guide medication selection for patients with MDD in a large, randomized, controlled trial (GUIDED).
Materials and Methods
Patients diagnosed with MDD who had an inadequate response to ≥1 psychotropic medication were randomized to treatment as usual (TAU) or combinatorial pharmacogenomic test-guided care (guided-care). All received combinatorial pharmacogenomic testing and medications were categorized by predicted GDI (no, moderate, or significant GDI). Patients and raters were blinded to study arm, and physicians were blinded to test results for patients in TAU, through week 8. Measures included adverse events (AEs, present/absent), worsening suicidal ideation (increase of ≥1 on the corresponding HAM-D17 question), or symptom worsening (HAM-D17 increase of ≥1). These measures were evaluated based on medication changes [add only, drop only, switch (add and drop), any, and none] and study arm, as well as baseline medication GDI.
Results
Most patients had a medication change between baseline and week 8 (938/1,166; 80.5%), including 269 (23.1%) who added only, 80 (6.9%) who dropped only, and 589 (50.5%) who switched medications. In the full cohort, changing medications resulted in an increased relative risk (RR) of experiencing AEs at both week 4 and 8 [RR 2.00 (95% CI 1.41–2.83) and RR 2.25 (95% CI 1.39–3.65), respectively]. This was true regardless of arm, with no significant difference observed between guided-care and TAU, though the RRs for guided-care were lower than for TAU. Medication change was not associated with increased suicidal ideation or symptom worsening, regardless of study arm or type of medication change. Special attention was focused on patients who entered the study taking medications identified by pharmacogenomic testing as likely having significant GDI; those who were only taking medications subject to no or moderate GDI at week 8 were significantly less likely to experience AEs than those who were still taking at least one medication subject to significant GDI (RR 0.39, 95% CI 0.15–0.99, p=0.048). No other significant differences in risk were observed at week 8.
Conclusion
These data indicate that patient safety in the combinatorial pharmacogenomic test-guided care arm was no worse than TAU in the GUIDED trial. Moreover, combinatorial pharmacogenomic-guided medication selection may reduce some safety concerns. Collectively, these data demonstrate that combinatorial pharmacogenomic testing can be adopted safely into clinical practice without risking symptom degradation among patients.
Understanding place-based contributors to health requires geographically and culturally diverse study populations, but sharing location data is a significant challenge to multisite studies. Here, we describe a standardized and reproducible method to perform geospatial analyses for multisite studies. Using census tract-level information, we created software for geocoding and geospatial data linkage that was distributed to a consortium of birth cohorts located throughout the USA. Individual sites performed geospatial linkages and returned tract-level information for 8810 children to a central site for analyses. Our generalizable approach demonstrates the feasibility of geospatial analyses across study sites to promote collaborative translational research.
Among older people with cognitive impairment and mild dementia, relatively little is known about the factors that predict preferences for everyday living activities and experiences and that influence the relative importance of those activities and experiences.
Design:
Cross-sectional study.
Setting:
Participants were recruited from the Massachusetts Alzheimer’s Disease Research Center (MADRC) Clinical Core longitudinal cohort.
Participants:
The sample included 62 community-dwelling older adults with cognitive impairment (Clinical Dementia Rating global score ≥ 0.5).
Measurements:
We used the Preferences for Everyday Living Inventory (PELI) to assess preferences for activities and lifestyle experiences among persons with cognitive impairment. Within-subjects analysis of variance was used to test for significant differences in the mean ratings of importance for four domains of the PELI (“autonomous choice,” “social engagement,” “personal growth,” and “keeping a routine”). Multiple regression models were used to relate predictors, including neuropsychiatric symptoms, to importance ratings for each domain.
Results:
Significant differences were noted in the mean importance ratings of the preferences domains: “social engagement” preferences were rated as most important, followed by “autonomous choice,” “personal growth,” and “keeping a routine.” For the “social engagement” preferences domain, female sex was significantly associated with higher importance of “social engagement,” while depressive symptoms (Geriatric Depression Scale-15 scores) were significantly associated with lower importance.
Conclusions:
This study adds novel insight into the everyday preferences of community-dwelling older adults with cognitive impairment and highlights the impact of a number of factors, particularly level of depression, on how important various everyday experiences are perceived.
The Genomics Used to Improve DEpresssion Decisions (GUIDED) trial assessed outcomes associated with combinatorial pharmacogenomic (PGx) testing in patients with major depressive disorder (MDD). Analyses used the 17-item Hamilton Depression (HAM-D17) rating scale; however, studies demonstrate that the abbreviated, core depression symptom-focused, HAM-D6 rating scale may have greater sensitivity toward detecting differences between treatment and placebo. However, the sensitivity of HAM-D6 has not been tested for two active treatment arms. Here, we evaluated the sensitivity of the HAM-D6 scale, relative to the HAM-D17 scale, when assessing outcomes for actively treated patients in the GUIDED trial.
Methods:
Outpatients (N=1,298) diagnosed with MDD and an inadequate treatment response to >1 psychotropic medication were randomized into treatment as usual (TAU) or combinatorial PGx-guided (guided-care) arms. Combinatorial PGx testing was performed on all patients, though test reports were only available to the guided-care arm. All patients and raters were blinded to study arm until after week 8. Medications on the combinatorial PGx test report were categorized based on the level of predicted gene-drug interactions: ‘use as directed’, ‘moderate gene-drug interactions’, or ‘significant gene-drug interactions.’ Patient outcomes were assessed by arm at week 8 using HAM-D6 and HAM-D17 rating scales, including symptom improvement (percent change in scale), response (≥50% decrease in scale), and remission (HAM-D6 ≤4 and HAM-D17 ≤7).
Results:
At week 8, the guided-care arm demonstrated statistically significant symptom improvement over TAU using HAM-D6 scale (Δ=4.4%, p=0.023), but not using the HAM-D17 scale (Δ=3.2%, p=0.069). The response rate increased significantly for guided-care compared with TAU using both HAM-D6 (Δ=7.0%, p=0.004) and HAM-D17 (Δ=6.3%, p=0.007). Remission rates were also significantly greater for guided-care versus TAU using both scales (HAM-D6 Δ=4.6%, p=0.031; HAM-D17 Δ=5.5%, p=0.005). Patients taking medication(s) predicted to have gene-drug interactions at baseline showed further increased benefit over TAU at week 8 using HAM-D6 for symptom improvement (Δ=7.3%, p=0.004) response (Δ=10.0%, p=0.001) and remission (Δ=7.9%, p=0.005). Comparatively, the magnitude of the differences in outcomes between arms at week 8 was lower using HAM-D17 (symptom improvement Δ=5.0%, p=0.029; response Δ=8.0%, p=0.008; remission Δ=7.5%, p=0.003).
Conclusions:
Combinatorial PGx-guided care achieved significantly better patient outcomes compared with TAU when assessed using the HAM-D6 scale. These findings suggest that the HAM-D6 scale is better suited than is the HAM-D17 for evaluating change in randomized, controlled trials comparing active treatment arms.
Simulation plays an integral role in the Canadian healthcare system with applications in quality improvement, systems development, and medical education. High-quality, simulation-based research will ensure its effective use. This study sought to summarize simulation-based research activity and its facilitators and barriers, as well as establish priorities for simulation-based research in Canadian emergency medicine (EM).
Methods
Simulation-leads from Canadian departments or divisions of EM associated with a general FRCP-EM training program surveyed and documented active EM simulation-based research at their institutions and identified the perceived facilitators and barriers. Priorities for simulation-based research were generated by simulation-leads via a second survey; these were grouped into themes and finally endorsed by consensus during an in-person meeting of simulation leads. Priority themes were also reviewed by senior simulation educators.
Results
Twenty simulation-leads representing all 14 invited institutions participated in the study between February and May, 2018. Sixty-two active, simulation-based research projects were identified (median per institution = 4.5, IQR 4), as well as six common facilitators and five barriers. Forty-nine priorities for simulation-based research were reported and summarized into eight themes: simulation in competency-based medical education, simulation for inter-professional learning, simulation for summative assessment, simulation for continuing professional development, national curricular development, best practices in simulation-based education, simulation-based education outcomes, and simulation as an investigative methodology.
Conclusion
This study summarized simulation-based research activity in EM in Canada, identified its perceived facilitators and barriers, and built national consensus on priority research themes. This represents the first step in the development of a simulation-based research agenda specific to Canadian EM.
Major depressive disorder (MDD) is a leading cause of disease burden worldwide, with lifetime prevalence in the United States of 17%. Here we present the results of the first prospective, large-scale, patient- and rater-blind, randomized controlled trial evaluating the clinical importance of achieving congruence between combinatorial pharmacogenomic (PGx) testing and medication selection for MDD.
Methods
1,167 outpatients diagnosed with MDD and an inadequate response to ≥1 psychotropic medications were enrolled and randomized 1:1 to a Treatment as Usual (TAU) arm or PGx-guided care arm. Combinatorial PGx testing categorized medications in three groups based on the level of gene-drug interactions: use as directed, use with caution, or use with increased caution and more frequent monitoring. Patient assessments were performed at weeks 0 (baseline), 4, 8, 12 and 24. Patients, site raters, and central raters were blinded in both arms until after week 8. In the guided-care arm, physicians had access to the combinatorial PGx test result to guide medication selection. Primary outcomes utilized the Hamilton Depression Rating Scale (HAM-D17) and included symptom improvement (percent change in HAM-D17 from baseline), response (50% decrease in HAM-D17 from baseline), and remission (HAM-D17<7) at the fully blinded week 8 time point. The durability of patient outcomes was assessed at week 24. Medications were considered congruent with PGx test results if they were in the ‘use as directed’ or ‘use with caution’ report categories while medications in the ‘use with increased caution and more frequent monitoring’ were considered incongruent. Patients who started on incongruent medications were analyzed separately according to whether they changed to congruent medications by week8.
Results
At week 8, symptom improvement for individuals in the guided-care arm was not significantly different than TAU (27.2% versus 24.4%, p=0.11). However, individuals in the guided-care arm were more likely than those in TAU to achieve remission (15% versus 10%; p<0.01) and response (26% versus 20%; p=0.01). Remission rates, response rates, and symptom reductions continued to improve in the guided-treatment arm until the 24week time point. Congruent prescribing increased to 91% in the guided-care arm by week 8. Among patients who were taking one or more incongruent medication at baseline, those who changed to congruent medications by week 8 demonstrated significantly greater symptom improvement (p<0.01), response (p=0.04), and remission rates (p<0.01) compared to those who persisted on incongruent medications.
Conclusions
Combinatorial PGx testing improves short- and long-term response and remission rates for MDD compared to standard of care. In addition, prescribing congruency with PGx-guided medication recommendations is important for achieving symptom improvement, response, and remission for MDD patients.
Funding Acknowledgements: This study was supported by Assurex Health, Inc.
This work presents a study of the region of nanoparticle growth in an atmospheric pressure carbon arc. The nanoparticles are detected using the planar laser-induced incandescence technique. The measurements revealed large clouds of nanoparticles in the arc periphery bordering the region with a high density of diatomic carbon molecules. Two-dimensional computational fluid dynamic simulations of the arc combined with thermodynamic modeling show that this is due to the interplay of the condensation of carbon molecular species and the convection flow pattern. These results show that the nanoparticles are formed in the colder, peripheral regions of the arc and describe the parameters necessary for coagulation.
Despite the rapid expansion of online educational resources for emergency medicine, barriers remain to their effective use by emergency physicians and trainees. This article expands on previous descriptions of techniques to aggregate online educational resources, outlining four strategies to help learners navigate, evaluate, and contribute online. These strategies include 1) cultivating digital mentors, 2) browsing the most popular free open access medical education (FOAM) websites, 3) using critical appraisal tools developed for FOAM, and 4) contributing new online content.
The recent introduction of glufosinate-resistant and glyphosate-resistant crops provides growers with new options for weed management. Information is needed to compare the effectiveness of glufosinate and glyphosate on annual weeds. Greenhouse trials were conducted to determine the response of barnyardgrass (Echinochloa crus-galli), common lambsquarters (Chenopodium album), common ragweed (Ambrosia artemisiifolia), fall panicum (Panicum dichotomiflorum), giant foxtail (Setaria faberi), large crabgrass (Digitaria sanguinalis), and velvetleaf (Abutilon theophrasti) to glufosinate and glyphosate. The response of velvetleaf and common lambsquarters was investigated at multiple stages of growth. Glufosinate and glyphosate were applied to each weed species at logarithmically incremented rates. The glufosinate and glyphosate rates that provided a 50% reduction in aboveground weed biomass, commonly referred to as GR50 values, were compared using nonlinear regression techniques. Barnyardgrass, common ragweed, fall panicum, giant foxtail, and large crabgrass responded similarly to glufosinate and glyphosate. Common lambsquarters 4 to 8 cm in height was more sensitive to glufosinate than glyphosate. In contrast, 15- to 20-cm tall-velvetleaf was more sensitive to glyphosate than glufosinate.
Field trials were conducted in 1996 and 1997 to determine the influence of glufosinate and glyphosate application rates, application timings, and interrow cultivation on weed control and corn yield. Glufosinate-ammonium rates ranged from 0.18 to 0.41 kg ai/ha, while rates for the isopropylamine salt of glyphosate ranged from 0.21 to 0.84 kg ae/ha. Increasing rates of glufosinate and glyphosate often improved weed control. Control of many of the weed species was improved by delaying herbicide application timing. Weed control was most consistent from late postemergence (LPOST) applications of glufosinate at 0.41 kg ai/ha or glyphosate at 0.84 kg ae/ha. Corn yields were reduced due to incomplete weed control when the lowest rate of glufosinate was applied. Weed control from early postemergence (EPOST) glufosinate and glyphosate applications followed by cultivation was similar to weed control from LPOST glufosinate and glyphosate applications without cultivation. Interrow cultivation following glufosinate or glyphosate application did not affect corn yield.
Field studies were conducted from 1995 through 1998 to evaluate citronmelon control in peanut with various preplant and preemergence combinations of dimethenamid, flumioxazin, imazethapyr, lactofen, metolachlor, oxyfluorfen, and pendimethalin. Pendimethalin alone or in combination with imazethapyr, metolachlor, or dimethenamid did not control citronmelon. Flumioxazin alone, pendimethalin plus flumioxazin, or pendimethalin followed by (fb) lactofen controlled citronmelon at least 85% early season. Pendimethalin fb lactofen controlled citronmelon at least 75% late season, whereas all other herbicide treatments controlled less than 70%.
Field studies were conducted in 1999 and 2000 at seven locations in south Texas to evaluate flufenacet plus metribuzin for weed control and corn tolerance. Texas panicum control with flufenacet plus metribuzin was variable with less than 70% control in 1999 and greater than 75% control in 2000. Palmer amaranth and pitted morningglory control ranged from 41 to 100%. Corn stunting (4 to 13%) was noted in soils with greater than 75% sand. Corn yields with flufenacet and metribuzin combinations were increased up to 19% over the untreated check where stunting was not observed.
Field studies were conducted from 1995 through 1998 to evaluate citronmelon control with postemergence (POST) herbicides. Imazapic at any application timing and late postemergence (LPOST) applications of 2,4-DB were the only herbicides that provided >80% control of citronmelon late season. Other herbicides such as acifluorfen, imazethapyr, lactofen, and pyridate provided acceptable (>75%) early-season control of citronmelon, but control was inadequate at harvest.
Field studies were conducted in 1999 and 2000 at seven locations in south Texas to evaluate flufenacet plus isoxaflutole for weed control and corn tolerance. Palmer amaranth control with flufenacent plus isoxaflutole was variable, with no greater than 60% control at one location and greater than 95% control at another. The poor control at the one location was probably due to lack of rainfall for 3 to 4 wk after corn was planted. Flufenacet plus isoxaflutole at 0.56 or 0.7 kg/ha controlled Texas panicum at least 80%, whereas flufenacet plus isoxaflutole rates lower than 0.56 kg/ha provided variable control (55 to 99%). Flufenacet plus isoxaflutole at 0.35 and 0.49 kg/ha controlled pitted morningglory at least 83%. Corn stunting (3 to 16%) with flufenacet plus isoxaflutole was noted at the one location where the soil sand content was greater than 80% and moisture was received within 48 h of herbicide application. With few exceptions, corn weed control and yield with flufenacet plus isoxaflutole combinations were generally comparable to those observed for the atrazine and acetochlor standard treatments.
Field studies were conducted from 1996 through 1998 to evaluate control of broadleaf signalgrass and slender amaranth by clethodim, fluazifop-P-butyl, and fluazifop-P-butyl plus fenoxaprop-P-ethyl applied alone, in combination with pyrithiobac, or sequentially with pyrithiobac. Broadleaf signalgrass control with graminicides alone was 75 to 100%. Although broadleaf signalgrass control with clethodim was not reduced by pyrithiobac, control with fluazifop-P-butyl and fluazifop-P-butyl plus fenoxaprop-P-ethyl was reduced by pyrithiobac. Pyrithiobac controlled slender amaranth 85 to 100% when applied alone. However, slender amaranth control by pyrithiobac was inconsistent when pyrithiobac was applied in mixture or sequentially with graminicides. A reduction in slender amaranth control may have resulted from a combination of reduced graminicide efficacy and interference caused by broadleaf signalgrass with slender amaranth (pyrithiobac alone). Cotton yields were highest when pyrithiobac was applied 24 h after graminicides.
Field trials were conducted in 1998 and 1999 to determine the effect of delayed burndown timings on weed control and yield of no-tillage glyphosate-resistant corn planted into soybean residue and into a wheat cover crop. Burndown treatments containing glyphosate were applied to both trials when the corn was planted (PRE), when the corn began to emerge (SPIKE), or when the corn had three visible leaves (3-LEAF). As burndown timing was delayed, velvetleaf control increased in corn planted into soybean residue. Glyphosate applied at 0.84 kg ae/ha at the SPIKE or 3-LEAF timing followed by a sequential application of glyphosate at 0.84 kg/ha controlled velvetleaf 91% and corn yields were similar to the weed-free plots. Corn yields among the burndown treatments were directly related to velvetleaf control. In the wheat cover crop trial, wheat treated at the PRE timing was completely controlled and corn yields were similar to the weed-free plots. As burndown timings were delayed, corn emergence and yields were severely reduced. Glyphosate applied at 0.84 kg/ha to 25-cm-wide strips over the corn row at planting and followed with delayed burndown timings increased corn emergence and yield.