The Impact of Acute Diesel Exhaust Exposure on Executive Brain Function

Abstract Background Previous results from the Diesel Exhaust in Miners Study (DEMS) demonstrated a positive exposure–response relation between lung cancer and respirable elemental carbon (REC), a key surrogate for diesel exhaust exposure. Two issues have been raised regarding DEMS: (i) the use of historical carbon monoxide (CO) measurements to calibrate models used for estimating historical exposures to REC in the DEMS exposure assessment; and (ii) potential confounding by radon. Methods We developed alternative REC estimates using models that did not rely on CO for calibration, but instead relied on estimated use of diesel equipment, mine ventilation rates and changes in diesel engine emission rates over time. These new REC estimates were used to quantify cumulative REC exposure for each subject in the nested case-control study. We conducted conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals for lung cancer. To evaluate the impact of including radon as a potential confounder, we estimated ORs for average REC intensity adjusted for cumulative radon exposure in underground miners. Results Validation of the new REC exposure estimates indicated that they overestimated historical REC by 200–400%, compared with only 10% for the original estimates. Effect estimates for lung cancer using these alternative REC exposures or adjusting for radon typically changed by <10% when compared with the original estimates. Conclusions These results emphasize the robustness of the DEMS findings, support the use of CO for model calibration and confirm that radon did not confound the DEMS estimates of the effect of diesel exposure on lung cancer mortality.

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Effects of Short-Term Exposure to Diesel Exhaust on the Ecophysiology, Growth, and Fecundity of Soybean (Glycine max (L.) Merr.) and Chicory (Cichorium intybus L.)

The Ohio Journal of Science ◽

10.18061/ojs.v121i2.6936 ◽

2021 ◽

Vol 121 (2) ◽

pp. 21-32

Author(s):

Susan Y. Jaconis ◽

Theresa M. Culley ◽

Timothy Keener ◽

Alexandra M. Odom ◽

Robert Elam ◽

...

Keyword(s):

Glycine Max ◽

Plant Species ◽

Diesel Exhaust ◽

Recovery Period ◽

Ambient Air ◽

Cichorium Intybus ◽

Short Term ◽

Diesel Exhaust Exposure ◽

Glycine Max L ◽

The Impact

Plants growing along roadways are often exposed to vehicle exhaust containing both particulate matter (PM) and various gases that could affect gas exchange and thus plant reproduction. To investigate effects of diesel exhaust exposure on plant ecophysiology, growth, and fecundity, individuals of soybean (Glycine max (L.) Merr.) and chicory (Cichorium intybus L.) were exposed to either exhaust from a diesel generator or ambient air. Exposure occurred daily over a 5-day period (beginning 18 June 2013) using open-top chambers in an agricultural field in southwestern Ohio, United States. Plants were evaluated at 3 times (before, directly after exposure, and following a 5.5-week post-treatment recovery period) for photosynthetic rate (A), stomatal conductance (g), water use efficiency (WUE), stomatal clogging due to PM deposition, and number of nodes. Aboveground biomass, fruit number, mean seed number, and seed mass were measured for soybean after the recovery period. In soybean, A minimally decreased with exposure to diesel exhaust (compared to the control), but an increase in g and a decrease in WUE were detected after the exhaust treatment. Chicory exhibited a relatively low increase in A after the treatment, but there were no clear differences in g or WUE. Growth and fecundity were similar among all soybean plants directly after treatment, but after 5.5 weeks plants exposed to diesel exhaust had increased vegetative biomass while exhibiting no difference in fecundity. These plant species reacted differently to short-term diesel exhaust exposure, suggesting that the impact of diesel exhaust will depend on both the plant species and its physiology.

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Air pollution & the brain: Subchronic diesel exhaust exposure causes neuroinflammation and elevates early markers of neurodegenerative disease

Journal of Neuroinflammation ◽

10.1186/1742-2094-8-105 ◽

2011 ◽

Vol 8 (1) ◽

pp. 105 ◽

Cited By ~ 165

Author(s):

Shannon Levesque ◽

Michael J Surace ◽

Jacob McDonald ◽

Michelle L Block

Keyword(s):

Air Pollution ◽

Neurodegenerative Disease ◽

Diesel Exhaust ◽

Diesel Exhaust Exposure ◽

Early Markers ◽

The Brain

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Respiratory Filter Reduces the Cardiovascular Effects Associated With Diesel Exhaust Exposure

JACC Heart Failure ◽

10.1016/j.jchf.2015.07.018 ◽

2016 ◽

Vol 4 (1) ◽

pp. 55-64 ◽

Cited By ~ 15

Author(s):

Jefferson L. Vieira ◽

Guilherme V. Guimaraes ◽

Paulo A. de Andre ◽

Fátima D. Cruz ◽

Paulo H. Nascimento Saldiva ◽

...

Keyword(s):

Diesel Exhaust ◽

Cardiovascular Effects ◽

Diesel Exhaust Exposure

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Moderators of the Impact of (Poly)Phenols Interventions on Psychomotor Functions and BDNF: Insights from Subgroup Analysis and Meta-Regression

Nutrients ◽

10.3390/nu12092872 ◽

2020 ◽

Vol 12 (9) ◽

pp. 2872

Author(s):

Achraf Ammar ◽

Khaled Trabelsi ◽

Omar Boukhris ◽

Bassem Bouaziz ◽

Patrick Müller ◽

...

Keyword(s):

Phenolic Compounds ◽

Subgroup Analysis ◽

Psychomotor Performance ◽

Brain Function ◽

Significant Heterogeneity ◽

Moderator Variables ◽

Psychomotor Functions ◽

Meta Regression ◽

Participant Characteristics ◽

The Impact

Background: Recent anti-aging interventions have shown contradictory impacts of (poly)phenols regarding the prevention of cognitive decline and maintenance of brain function. These discrepancies have been linked to between-study differences in supplementation protocols. This subgroup analysis and meta-regression aimed to (i) examine differential effects of moderator variables related to participant characteristics and supplementation protocols and (ii) identify practical recommendations to design effective (poly)phenol supplementation protocols for future anti-aging interventions. Methods: Multiple electronic databases (Web of Science; PubMed) searched for relevant intervention published from inception to July 2019. Using the PICOS criteria, a total of 4303 records were screened. Only high-quality studies (n = 15) were included in the final analyses. Random-effects meta-analysis was used, and we calculated standard differences in means (SDM), effect size (ES), and 95% confidence intervals (CI) for two sufficiently comparable items (i.e., psychomotor function and brain-derived neurotrophic factor (BDNF)). When significant heterogeneity was computed (I2 > 50%), a subgroup and meta-regression analysis were performed to examine the moderation effects of participant characteristics and supplementation protocols. Results: The reviewed studies support the beneficial effect of (poly)phenols-rich supplementation on psychomotor functions (ES = −0.677, p = 0.001) and brain plasticity (ES = 1.168, p = 0.028). Subgroup analysis revealed higher beneficial impacts of (poly)phenols (i) in younger populations compared to older (SDM = −0.89 vs. −0.47 for psychomotor performance, and 2.41 vs. 0.07 for BDNF, respectively), (ii) following an acute compared to chronic supplementation (SDM = −1.02 vs. −0.43 for psychomotor performance), and (iii) using a phenolic compound with medium compared to low bioavailability rates (SDM = −0.76 vs. −0.68 for psychomotor performance and 3.57 vs. 0.07 for DBNF, respectively). Meta-regressions revealed greater improvement in BDNF levels with lower percentages of female participants (Q = 40.15, df = 6, p < 0.001) and a skewed scatter plot toward a greater impact using higher (poly)phenols doses. Conclusion: This review suggests that age group, gender, the used phenolic compounds, their human bioavailability rate, and the supplementation dose as the primary moderator variables relating to the beneficial effects of (poly)phenol consumption on cognitive and brain function in humans. Therefore, it seems more advantageous to start anti-aging (poly)phenol interventions in adults earlier in life using medium (≈500 mg) to high doses (≈1000 mg) of phenolic compounds, with at least medium bioavailability rate (≥9%).

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Diesel exhaust exposure favors TH2 cell recruitment in nonatopic subjects by differentially regulating chemokine production

Journal of Allergy and Clinical Immunology ◽

10.1016/j.jaci.2006.04.050 ◽

2006 ◽

Vol 118 (2) ◽

pp. 354-360 ◽

Cited By ~ 19

Author(s):

Ying Chang ◽

Stéphanie Sénéchal ◽

Patricia de Nadai ◽

Cécile Chenivesse ◽

Jules Gilet ◽

...

Keyword(s):

Diesel Exhaust ◽

Chemokine Production ◽

Cell Recruitment ◽

Diesel Exhaust Exposure ◽

Th2 Cell

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Sex differences in the circadian regulation of sleep and waking cognition in humans

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1521637113 ◽

2016 ◽

Vol 113 (19) ◽

pp. E2730-E2739 ◽

Cited By ~ 106

Author(s):

Nayantara Santhi ◽

Alpar S. Lazar ◽

Patrick J. McCabe ◽

June C. Lo ◽

John A. Groeger ◽

...

Keyword(s):

Sex Differences ◽

Performance Measures ◽

Brain Function ◽

Early Morning ◽

Circadian Rhythmicity ◽

Men And Women ◽

Circadian Phase ◽

Time Awake ◽

Everyday Performance ◽

The Impact

The sleep–wake cycle and circadian rhythmicity both contribute to brain function, but whether this contribution differs between men and women and how it varies across cognitive domains and subjective dimensions has not been established. We examined the circadian and sleep–wake-dependent regulation of cognition in 16 men and 18 women in a forced desynchrony protocol and quantified the separate contributions of circadian phase, prior sleep, and elapsed time awake on cognition and sleep. The largest circadian effects were observed for reported sleepiness, mood, and reported effort; the effects on working memory and temporal processing were smaller. Although these effects were seen in both men and women, there were quantitative differences. The amplitude of the circadian modulation was larger in women in 11 of 39 performance measures so that their performance was more impaired in the early morning hours. Principal components analysis of the performance measures yielded three factors, accuracy, effort, and speed, which reflect core performance characteristics in a range of cognitive tasks and therefore are likely to be important for everyday performance. The largest circadian modulation was observed for effort, whereas accuracy exhibited the largest sex difference in circadian modulation. The sex differences in the circadian modulation of cognition could not be explained by sex differences in the circadian amplitude of plasma melatonin and electroencephalographic slow-wave activity. These data establish the impact of circadian rhythmicity and sex on waking cognition and have implications for understanding the regulation of brain function, cognition, and affect in shift-work, jetlag, and aging.

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