Intra-neighborhood associations between residential greenness and blood pressure.

INTRODUCTION: Previous investigations have reported that individuals living in greener neighborhoods have better cardiovascular health. It is unclear whether the effects reported at large geographic scales persist when examined at an intra-neighborhood level. The effects of greenness have not been thoroughly examined using high-resolution metrics of greenness exposure, and how they vary with spatial scales of assessment or participant characteristics. METHODS: We conducted a cross-sectional assessment of associations between blood pressure and multiple high-resolution measures of residential area greenness in spatially concentrated HEAL Study cohort of the Green Heart Project. We employed generalized linear models, accounting for individual-level covariates, to examine associations between different high-resolution measures of greenness and blood pressure among 667 participants in a 4 sq. mile contiguous neighborhood area in Louisville, KY. RESULTS: In adjusted models, we observed significant inverse associations between residential greenness, measured by leaf area index (LAI), and systolic blood pressure (SBP) within 150-250 m and 500 m of homes, but not for Normalized Difference Vegetation Index (NDVI) or grass cover. Weaker associations were also found with diastolic blood pressure (DBP). Significant positive associations were observed between LAI and SBP among participants who reported being female, White, without obesity, non-exercisers, non-smokers, younger age, of lower income, and who had high nearby roadway traffic. We found few significant associations between grass cover and SBP, but an inverse association in those with obesity, but positive associations for those without obesity. CONCLUSIONS: We found that leaf surface area of trees around participants home is strongly associated with lower blood pressure, with little association with grass cover. These effects varied with participant characteristics and spatial scales. More research is needed to test causative links between greenspace types and cardiovascular health and to develop population-, typology-, and place-based evidence to inform greening interventions.

Cardiovascular Health Effects and Synthetic Cooling Agents in E-cigarettes Labeled as 'clear' Marketed in Massachusetts After the Tobacco Product Flavoring Ban.

Introduction: Massachusetts (MA) enacted statewide regulation on all flavored tobacco products in June 2020. Thereafter, electronic cigarettes (e-cigarettes) labeled 'clear' emerged on the market. We aimed to combine cardiovascular health effects with chemical analysis of 'clear' e-cigarettes. Methods: We measured acute changes in blood pressure and heart rate following a 10-minute structured use of participants' own e-cigarette, comparing 'clear' e-cigarette users with other flavored e-cigarette users and non-users. Chemical characterization and quantification of relevant flavorings and cooling agents (WS-3, WS-23) of 19 'clear'-labeled disposable e-cigarette liquids was carried out by GC/MS. Results: After the ban, participants that used 'clear' labeled e-cigarettes increased from 0% to 21%. Increase in diastolic blood pressure and heart rate was significantly greater in 'clear' e-cigarettes users (n=22) compared to both non-'clear' flavored e-cigarette users (n=114) and non-users (n=72). We saw similar results in heart rate when comparing Juul e-cigarette and 'clear' users; Juul was used as a reference as synthetic coolants WS-3 or WS-23 were not detected in these.All (19/19) 'clear' e-liquids were found to contain synthetic cooling agents WS-23 and/or WS-3, menthol (18/19), as well as other flavorings (12/19). Discussion: The detected presence of menthol alongside other flavorings in tested 'clear' products is a direct violation of the MA flavored tobacco product regulation, warranting stricter monitoring for new products and constituents. 'clear' e-cigarette use led to greater hemodynamic effects compared to other flavored e-cigarettes and Juul, which raises questions about the effect of cooling agents on users.

Individual NMDA receptor GluN2 subunit signaling domains differentially regulate the postnatal maturation of hippocampal excitatory synaptic transmission and plasticity but not dendritic morphology.

N-methyl-d-aspartate receptors (NMDARs) at hippocampal excitatory synapses undergo a late postnatal shift in subunit composition, from an initial prevalence of GluN2B subunit incorporation to a later predominance of GluN2A. This GluN2B to GluN2A shift alters NMDAR calcium conductance dynamics and intracellular molecular signaling that are individually regulated by distinct GluN2 signaling domains and temporally align with developmental alterations in dendritic and synaptic plasticity. However, the impacts of individual GluN2B to GluN2A signaling domains on neuronal development remain unknown. Ionotropic and intracellular signaling domains of GluN2 subunits were separated by creating chimeric GluN2 subunits that were expressed in two transgenic mouse lines. Western blot and immunoprecipitation revealed that roughly one third of native synaptic NMDARs were replaced by transformed NMDARs without altering total synaptic NMDAR content. Schaffer collateral synaptic strength was transiently increased in acutely prepared hippocampal slices at just over 3 weeks of age in animals overexpressing the GluN2B carboxy terminus. Long-term potentiation (LTP) induction following lower frequency stimulation was regulated by GluN2 ionotropic signaling domains in an age-dependent manner and LTP maintenance was enhanced by overexpression of the GluN2B CTD in mature animals. After higher frequency stimulation, the induction and maintenance of LTP were increased in young adult animals overexpressing the GluN2B ionotropic signaling domains but reduced in juveniles just over 3 weeks of age. Confocal imaging of green fluorescent protein (GFP)- labeled CA1 pyramidal neurons revealed no alterations in dendritic morphology or spine density in mice expressing chimeric GluN2 subunits. These results illustrate how individual GluN2 subunit signaling domains do or do not control physiological and morphological development of hippocampal excitatory neurons and better clarify the neurobiological factors that govern hippocampal maturation. SIGNIFICANCE STATEMENT: A developmental reduction in the magnitude of hippocampal long-term synaptic potentiation (LTP) and a concomitant improvement in spatial maze performance coincide with greater incorporation of GluN2A subunits into synaptic NMDARs. Corroborating our prior discovery that overexpression of GluN2A-type ionotropic signaling domains enables context-based navigation in immature mice, GluN2A-type ionotropic signaling domain overexpression reduces LTP induction threshold and magnitude in immature mice. Also, we previously found that GluN2B carboxy terminal domain (CTD) overexpression enhances long-term spatial memory in mature mice and now report that the GluN2B CTD is associated with greater amplitude of LTP after induction in mature mice. Thus, the late postnatal maturation of context encoding likely relies on a shift toward GluN2A-type ionotropic signaling and a reduction in the threshold to induce LTP while memory consolidation and LTP maintenance are regulated by GluN2B subunit CTD signaling.

Greenspaces And Cardiovascular Health.

Accumulating evidence suggests that living in areas of high surrounding greenness or even brief exposures to areas of high greenery is conducive to cardiovascular health, which may be related to the environmental, social, psychological, and physiological benefits of greenspaces. Recent data from multiple cross-sectional, longitudinal, and cohort studies suggest that living in areas of high surrounding greenness is associated with a lower risk of all-cause and cardiovascular mortality. High levels of neighborhood greenery have been linked also to a decrease in the burden of cardiovascular disease risk factors as reflected by lower rates of hypertension, dyslipidemia, and diabetes. Those who live in greener environments report better mental health and more frequent social interactions, which can benefit cardiovascular health as well. In this narrative review, we discuss evidence linking greenspaces to cardiovascular health as well as the potential mechanisms underlying the beneficial effects of greenspaces, including the impact of vegetation on air, noise and light pollution, ambient temperature, physical activity, mental health, and biodiversity. We review literature on the beneficial effects of acute and chronic exposure to nature on cardiovascular disease risk factors, inflammation and immune function, and we highlight the potential cardiovascular effects of biogenic volatile organic compounds that are emitted by trees and shrubs. We identify current knowledge gaps in this area and underscore the need for additional population studies to understand more clearly and precisely the link between greenness and health. Such understanding is urgently needed to fully redeem the promise of greenspaces in preventing adverse environmental exposures, mitigating the effects of climate change, and creating healthier living environments.

Dynamic SARS-CoV-2 surveillance model combining seroprevalence and wastewater concentrations for post-vaccine disease burden estimates.

BACKGROUND: Despite wide scale assessments, it remains unclear how large-scale severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination affected the wastewater concentration of the virus or the overall disease burden as measured by hospitalization rates. METHODS: We used weekly SARS-CoV-2 wastewater concentration with a stratified random sampling of seroprevalence, and linked vaccination and hospitalization data, from April 2021-August 2021 in Jefferson County, Kentucky (USA). Our susceptible ( S ), vaccinated ( V ), variant-specific infected ( I 1 and I 2 ), recovered ( R ), and seropositive ( T ) model ( S V I 2 R T ) tracked prevalence longitudinally. This was related to wastewater concentration. RESULTS: Here we show the 64% county vaccination rate translate into about a 61% decrease in SARS-CoV-2 incidence. The estimated effect of SARS-CoV-2 Delta variant emergence is a 24-fold increase of infection counts, which correspond to an over 9-fold increase in wastewater concentration. Hospitalization burden and wastewater concentration have the strongest correlation (r = 0.95) at 1 week lag. CONCLUSIONS: Our study underscores the importance of continuing environmental surveillance post-vaccine and provides a proof-of-concept for environmental epidemiology monitoring of infectious disease for future pandemic preparedness.

It is unclear how large-scale COVID-19 vaccination impacts wastewater concentration or overall disease burden. Here, we developed a mathematical surveillance model that allows estimation of overall vaccine impact based on the amount of SARS-CoV-2 in wastewater, seroprevalence and the number of cases admitted to hospitals between April 2021­August 2021 in Jefferson County, Kentucky USA. We found that a 64% vaccination coverage correlated to a 61% decrease in COVID-19 cases. The emergence of the SARS-CoV-2 Delta variant during the time of the surveillance directly correlated with a sharp increase in infection incidence as well as viral counts in wastewater. The hospitalization burden was closely reflected by the viral count found in the wastewater, indicating that post-vaccine environmental surveillance can be an effective method of estimating changing disease prevalence in future pandemics.

Biological Sex as a Moderator of Work Determinants of Health: Implications for Work and Stress.

This study examined whether biological sex moderates the relationship between experiences of workplace culture and urinary levels of catecholamines and their metabolites. We conducted a series of regression analyses (predictors: 3-methoxytyramine (3MT), 5-hydroxyindolacetic (5HIAA), and dopamine (DA); outcomes: employee engagement and workplace culture) in a sample of 218 participants. Compared to men, women rated workplace culture less positively (r = -0.210; p < 0.01) and had stronger positive associations with 3MT (r = 0.328; p < 0.001), DA (r = 0.376; p < 0.001), and 5HIAA (r = 0.168; p < 0.01). There was a significant moderation effect between 3MT and sex on employee engagement (b = -1.76 (SE = 0.84); p < 0.01), and 3MT had a positive significant association for men with engagement (p < 0.05); however, there was no significant association for women. Findings suggest that for women, less positive experiences with workplace culture could elevate 3MT, stimulating sympathetic nervous tone and potentially amplifying risks for negative health outcomes. Conversely, men who reported higher employee engagement had higher levels of 3MT, suggesting possible health risks associated with high levels of engagement, rather than lack of engagement. Overall, study findings suggested differential health risks based on biological sex, potentially impacting health risk policy development.

Evaluation of urinary limonene metabolites as biomarkers of exposure to greenness.

Exposure to plants is known to improve physical and mental health and living in areas of high vegetation is associated with better health. The addition of quantitative measures of greenness exposure at individual-level to other objective and subjective study measures will help establish cause-and-effect relationships between greenspaces and human health. Because limonene is one of the most abundant biogenic volatile organic compounds emitted by plants, we hypothesized that urinary metabolites of inhaled limonene can serve as biomarkers of exposure to greenness. To test our hypothesis, we analyzed urine samples collected from eight human volunteers after limonene inhalation or after greenness exposure using liquid chromatography-high resolution mass spectrometry-based profiling. Eighteen isomers of nine metabolites were detected in urine after limonene inhalation, and their kinetic parameters were estimated using nonlinear mixed effect models. Urinary levels of most abundant limonene metabolites were elevated after brief exposure to a forested area, and the ratio of urinary limonene metabolites provided evidence of recent exposure. The identities and structures of these metabolites were validated using stable isotope tracing and tandem mass spectral comparison. Together, these data suggest that urinary metabolites of limonene, especially uroterpenol glucuronide and dihydroperillic acid glucuronide, could be used as individualized biomarkers of greenness exposure.

The Green Heart Project: Objectives, Design, and Methods.

The Green Heart Project is a community-based trial to evaluate the effects of increasing greenery on urban environment and community health. The study was initiated in 2018 in a low-to-middle-income mixed-race residential area of nearly 28,000 residents in Louisville, KY. The 4 square mile area was surveyed for land use, population characteristics, and greenness, and assigned to 8 paired clusters of demographically- and environmentally matched "target" (T) and adjacent "control" (C), clusters. Ambient levels of ultrafine particles, ozone, oxides of nitrogen, and environmental noise were measured in each cluster. Individual-level data were acquired during in-person exams of 735 participants in Wave 1 (2018-2019) and 545 participants in Wave 2 (2021) to evaluate sociodemographic and psychosocial factors. Blood, urine, nail, and hair samples were collected to evaluate standard cardiovascular risk factors, inflammation, stress, and pollutant exposure. Cardiovascular function was assessed by measuring arterial stiffness and flow-mediated dilation. After completion of Wave 2, more than 8,000 mature, mostly evergreen, trees and shrubs were planted in the T clusters in 2022. Post planting environmental and individual-level data were collected during Wave 3 (2022) from 561 participants. We plan to continue following changes in area characteristics and participant health to evaluate the long-term impact of increasing urban greenery.

Global Profiling of Urinary Mercapturic Acids Using Integrated Library-Guided Analysis.

Urinary mercapturic acids (MAs) are often used as biomarkers for monitoring human exposures to occupational and environmental xenobiotics. In this study, we developed an integrated library-guided analysis workflow using ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry. This method includes expanded assignment criteria and a curated library of 220 MAs and addresses the shortcomings of previous untargeted approaches. We employed this workflow to profile MAs in the urine of 70 participants─40 nonsmokers and 30 smokers. We found approximately 500 MA candidates in each urine sample, and 116 MAs from 63 precursors were putatively annotated. These include 25 previously unreported MAs derived mostly from alkenals and hydroxyalkenals. Levels of 68 MAs were comparable in nonsmokers and smokers, 2 MAs were higher in nonsmokers, and 46 MAs were elevated in smokers. These included MAs of polycyclic aromatic hydrocarbons and hydroxyalkenals and those derived from toxicants present in cigarette smoke (e.g., acrolein, 1,3-butadiene, isoprene, acrylamide, benzene, and toluene). Our workflow allowed profiling of known and unreported MAs from endogenous and environmental sources, and the levels of several MAs were increased in smokers. Our method can also be expanded and applied to other exposure-wide association studies.

The Role of Perceived Neighborhood Cohesion in the Association between Depressive Symptoms and Cigarette Smoking.

BACKGROUND: Greater depression has been linked to increased smoking rates. However, the mechanisms underlying this association are not fully understood. It is possible that high perceived neighborhood cohesion may serve as one such mechanism given its associations with decreased depression and smoking. Having increased levels of depression likely impacts one's perceptions of neighborhood cohesion, which could lead to further increases in depression and a need to manage these symptoms via cigarette smoking. As a first test of this theory, the current study examined the effect of neighborhood cohesion on the association between depressive symptoms and smoking frequency and quantity among past 30-day cigarette smokers. METHODS: Participants were 201 combustible cigarette smokers (Mage = 48.33, SD = 11.64; 63.2% female; 68.2% White) who completed self-report measures as part of a larger study of environmental influences on cardiac health. RESULTS: Greater depressive symptoms were associated with lower levels of perceived neighborhood cohesion, and there was a significant indirect effect of greater depressive symptoms on heavier smoking through decreased neighborhood cohesion (b = .07, SE = .04, 95% CI [.003, .15]). There was no significant indirect effect for daily smoking. CONCLUSION: These results suggest that neighborhood cohesion is an important contextual factor that serves as one explanatory mechanism for the well-established relationship between depression and smoking quantity. Thus, there may be utility in implementing interventions focused on increasing neighborhood cohesion as a way to decrease smoking behavior.

Greenness and equity: Complex connections between intra-neighborhood contexts and residential tree planting implementation.

Associations between neighborhood greenness and socioeconomic status (SES) are established, yet intra-neighborhood context and SES-related barriers to tree planting remain unclear. Large-scale tree planting implementation efforts are increasingly common and can improve human health, strengthen climate adaptation, and ameliorate environmental inequities. Yet, these efforts may be ineffective without in-depth understanding of local SES inequities and barriers to residential planting. We recruited 636 residents within and surrounding the Oakdale Neighborhood of Louisville, Kentucky, USA, and evaluated associations of individual and neighborhood-level sociodemographic indicators with greenness levels at multiple scales. We offered no-cost residential tree planting and maintenance to residents within a subsection of the neighborhood and examined associations of these sociodemographic indicators plus baseline greenness levels with tree planting adoption among 215 eligible participants. We observed positive associations of income with Normalized Difference Vegetation Index (NDVI) and leaf area index (LAI) within all radii around homes, and within yards of residents, that varied in strength. There were stronger associations of income with NDVI in front yards but LAI in back yards. Among Participants of Color, associations between income and NDVI were stronger than with Whites and exhibited no association with LAI. Tree planting uptake was not associated with income, education, race, nor employment status, but was positively associated with lot size, home value, lower population density, and area greenness. Our findings reveal significant complexity of intra-neighborhood associations between SES and greenness that could help shape future research and equitable greening implementation. Results show that previously documented links between SES and greenspace at large scales extend to residents' yards, highlighting opportunities to redress greenness inequities on private property. Our analysis found that uptake of no-cost residential planting and maintenance was nearly equal across SES groups but did not redress greenness inequity. To inform equitable greening, further research is needed to evaluate culture, norms, perceptions, and values affecting tree planting acceptance among low-SES residents.

Stratified Simple Random Sampling Versus Volunteer Community-Wide Sampling for Estimates of COVID-19 Prevalence.

Objectives. To evaluate community-wide prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using stratified simple random sampling. Methods. We obtained data for the prevalence of SARS-CoV-2 in Jefferson County, Kentucky, from adult random (n = 7296) and volunteer (n = 7919) sampling over 8 waves from June 2020 through August 2021. We compared results with administratively reported rates of COVID-19. Results. Randomized and volunteer samples produced equivalent prevalence estimates (P < .001), which exceeded the administratively reported rates of prevalence. Differences between them decreased as time passed, likely because of seroprevalence temporal detection limitations. Conclusions. Structured targeted sampling for seropositivity against SARS-CoV-2, randomized or voluntary, provided better estimates of prevalence than administrative estimates based on incident disease. A low response rate to stratified simple random sampling may produce quantified disease prevalence estimates similar to a volunteer sample. Public Health Implications. Randomized targeted and invited sampling approaches provided better estimates of disease prevalence than administratively reported data. Cost and time permitting, targeted sampling is a superior modality for estimating community-wide prevalence of infectious disease, especially among Black individuals and those living in disadvantaged neighborhoods. (Am J Public Health. 2023;113(7):768-777. https://doi.org/10.2105/AJPH.2023.307303).

Associations of bedroom PM2.5, CO2, temperature, humidity, and noise with sleep: An observational actigraphy study.

OBJECTIVE: Climate change and urbanization increasingly cause extreme conditions hazardous to health. The bedroom environment plays a key role for high-quality sleep. Studies objectively assessing multiple descriptors of the bedroom environment as well as sleep are scarce. METHODS: Particulate matter with a particle size <2.5 µm (PM2.5), temperature, humidity, carbon dioxide (CO2), barometric pressure, and noise levels were continuously measured for 14 consecutive days in the bedroom of 62 participants (62.9% female, mean ± SD age: 47.7 ± 13.2 years) who wore a wrist actigraph and completed daily morning surveys and sleep logs. RESULTS: In a hierarchical mixed effect model that included all environmental variables and adjusted for elapsed sleep time and multiple demographic and behavioral variables, sleep efficiency calculated for consecutive 1-hour periods decreased in a dose-dependent manner with increasing levels of PM2.5, temperature, CO2, and noise. Sleep efficiency in the highest exposure quintiles was 3.2% (PM2.5, p < .05), 3.4% (temperature, p < .05), 4.0% (CO2, p < .01), and 4.7% (noise, p < .0001) lower compared to the lowest exposure quintiles (all p-values adjusted for multiple testing). Barometric pressure and humidity were not associated with sleep efficiency. Bedroom humidity was associated with subjectively assessed sleepiness and poor sleep quality (both p < .05), but otherwise environmental variables were not statistically significantly associated with actigraphically assessed total sleep time and wake after sleep onset or with subjectively assessed sleep onset latency, sleep quality, and sleepiness. Assessments of bedroom comfort suggest subjective habituation irrespective of exposure levels. CONCLUSIONS: These findings add to a growing body of evidence highlighting the importance of the bedroom environment-beyond the mattress-for high-quality sleep.

Exposure to Volatile Organic Compounds Is Associated with Hypertension in Black Adults: The Jackson Heart Study.

BACKGROUND: The prevalence of hypertension is higher among Black adults than among White and Hispanic adults. Nevertheless, reasons underlying the higher rates of hypertension in the Black population remain unclear but may relate to exposure to environmental chemicals such as volatile organic compounds (VOCs). METHODS: We evaluated the associations of blood pressure (BP) and hypertension with VOC exposure in non-smokers and smokers in a subgroup of the Jackson Heart Study (JHS), consisting of 778 never smokers and 416 age- and sex-matched current smokers. We measured urinary metabolites of 17 VOCs by mass spectrometry. RESULTS: After adjusting for covariates, we found that amoong non-smokers, metabolites of acrolein and crotonaldehyde were associated with a 1.6 mm Hg (95%CI: 0.4, 2.7; p = 0.007) and a 0.8 mm Hg (95%CI: 0.01, 1.6; p = 0.049) higher systolic BP, and the styrene metabolite was associated with a 0.4 mm Hg (95%CI: 0.09, 0.8, p = 0.02) higher diastolic BP. Current smokers had 2.8 mm Hg (95% CI 0.5, 5.1) higher systolic BP. They were at higher risk of hypertension (relative risk = 1.2; 95% CI, 1.1, 1.4), and had higher urinary levels of several VOC metabolites. Individuals who smoke had higher levels of the urinary metabolites of acrolein, 1,3-butadiene, and crotonaldehyde and were associated with higher systolic BP. The associations were stronger among participants who were <60 years of age and male. Using Bayesian kernel machine regression to assess the effects of multiple VOC exposures, we found that the relationship between VOCs and hypertension among non-smokers was driven primarily by acrolein and styrene in non-smokers, and crotonaldehyde in smokers. CONCLUSIONS: Hypertension in Black individuals may be attributed, in part, to VOC exposure from the environment or tobacco smoke.

Associations between residential volatile organic compound exposures and liver injury markers: The role of biological sex and race.

While occupational exposures to volatile organic compounds (VOCs) have been linked to steatohepatitis and liver cancer in industrial workers, recent findings have also positively correlated low-dose, residential VOC exposures with liver injury markers. VOC sources are numerous; factors including biological make up (sex), socio-cultural constructs (gender, race) and lifestyle (smoking) can influence both VOC exposure levels and disease outcomes. Therefore, the current study's objective is to investigate how sex and race influence associations between residential VOC exposures and liver injury markers particularly in smokers vs. nonsmokers. Subjects (n = 663) were recruited from residential neighborhoods; informed consent was obtained. Exposure biomarkers included 16 urinary VOC metabolites. Serological disease biomarkers included liver enzymes, direct bilirubin, and hepatocyte death markers (cytokeratin K18). Pearson correlations and generalized linear models were conducted. Models were adjusted for common liver-related confounders and interaction terms. The study population constituted approximately 60% females (n = 401) and 40% males (n = 262), and a higher percent of males were smokers and/or frequent drinkers. Both sexes had a higher percent of White (75% females, 82% males) vs. Black individuals. Positive associations were identified for metabolites of acrolein, acrylamide, acrylonitrile, butadiene, crotonaldehyde, and styrene with alkaline phosphatase (ALP), a biomarker for cholestatic injury; and for the benzene metabolite with bilirubin; only in females. These associations were retained in female smokers. Similar associations were also observed between these metabolites and ALP only in White individuals (n = 514). In Black individuals (n = 114), the styrene metabolite was positively associated with aspartate transaminase. Interaction models indicated that positive associations for acrylamide/crotonaldehyde metabolites with ALP in females were dose-dependent. Most VOC associations with K18 markers were negative in this residential population. Overall, the findings demonstrated that biological sex, race, and smoking status influence VOC effects on liver injury and underscored the role of biological-social-lifestyle factor(s) interactions when addressing air pollution-related health disparities.

Pod-based e-liquids impair human vascular endothelial cell function.

Pod-based electronic (e-) cigarettes more efficiently deliver nicotine using a protonated formulation. The cardiovascular effects associated with these devices are poorly understood. We evaluated whether pod-based e-liquids and their individual components impair endothelial cell function. We isolated endothelial cells from people who are pod users (n = 10), tobacco never users (n = 7), and combustible cigarette users (n = 6). After a structured use, pod users had lower acetylcholine-mediated endothelial nitric oxide synthase (eNOS) activation compared with never users and was similar to levels from combustible cigarette users (overall P = 0.008, P = 0.01 pod vs never; P = 0.96 pod vs combustible cigarette). The effects of pod-based e-cigarettes and their constituents on vascular cell function were further studied in commercially available human aortic endothelial cells (HAECs) incubated with flavored JUUL e-liquids or propylene glycol (PG):vegetable glycerol (VG) at 30:70 ratio with or without 60 mg/mL nicotine salt for 90 min. A progressive increase in cell death with JUUL e-liquid exposure was observed across 0.0001-1% dilutions; PG:VG vehicle with and without nicotine salt induced cell death. A23187-stimulated nitric oxide production was decreased with all JUUL e-liquid flavors, PG:VG and nicotine salt exposures. Aerosols generated by JUUL e-liquid heating similarly decreased stimulated nitric oxide production. Only mint flavored e-liquids increased inflammation and menthol flavored e-liquids enhanced oxidative stress in HAECs. In conclusion, pod e-liquids and their individual components appear to impair endothelial cell function. These findings indicate the potential harm of pod-based devices on endothelial cell function and thus may be relevant to cardiovascular injury in pod type e-cigarette users.

Wastewater and seroprevalence for pandemic preparedness: variant analysis, vaccination effect, and hospitalization forecasting for SARS-CoV-2, in Jefferson County, Kentucky.

Despite wide scale assessments, it remains unclear how large-scale SARS-CoV-2 vaccination affected the wastewater concentration of the virus or the overall disease burden as measured by hospitalization rates. We used weekly SARS-CoV-2 wastewater concentration with a stratified random sampling of seroprevalence, and linked vaccination and hospitalization data, from April 2021-August 2021 in Jefferson County, Kentucky (USA). Our susceptible (S), vaccinated (V), variant-specific infected I1 and I2, recovered (R), and seropositive (T) model SVI2RT tracked prevalence longitudinally. This was related to wastewater concentration. The 64% county vaccination rate translated into about 61% decrease in SARS-CoV-2 incidence. The estimated effect of SARS-CoV-2 Delta variant emergence was a 24-fold increase of infection counts, which corresponded to an over 9-fold increase in wastewater concentration. Hospitalization burden and wastewater concentration had the strongest correlation (r = 0.95) at 1 week lag. Our study underscores the importance of continued environmental surveillance post-vaccine and provides a proof-of-concept for environmental epidemiology monitoring of infectious disease for future pandemic preparedness.

Association of electronic cigarette use with circulating angiogenic cell levels in healthy young adults: Evidence for chronic systemic injury.

BACKGROUND: Circulating angiogenic cells (CACs) are indicative of vascular health and repair capacity; however, their relationship with chronic e-cigarette use is unclear. This study aims to assess the association between e-cigarette use and CAC levels. METHODS: We analyzed CAC levels in 324 healthy participants aged 21-45 years from the cross-sectional Cardiovascular Injury due to Tobacco Use study in four groups: never tobacco users (n = 65), sole e-cigarette users (n = 19), sole combustible cigarette users (n = 212), and dual users (n = 28). A total of 15 CAC subpopulations with four cell surface markers were measured using flow cytometry: CD146 (endothelial), CD34 (stem), CD45 (leukocyte), and AC133 (early progenitor/stem). Generalized linear models with gamma distribution and log-link were generated to assess association between CACs and smoking status. Benjamini-Hochberg were used to adjust p-values for multiple comparisons. RESULTS: The cohort was 47% female, 51% Black/African American, with a mean (± SD) age of 31 ± 7 years. Sole cigarette use was significantly associated with higher levels of two endothelial marker CACs (Q ⩽ 0.05). Dual users had higher levels of four endothelial marker CACs and one early progenitor/stem marker CAC (Q ⩽ 0.05). Sole e-cigarette users had higher levels of one endothelial and one leukocyte marker CAC (Q ⩽ 0.05). CONCLUSION: Dual use of e-cigarettes and combustible cigarettes was associated with higher levels of endothelial origin CACs, indicative of vascular injury. Sole use of e-cigarettes was associated with higher endothelial and inflammatory CACs, suggesting ongoing systemic injury. Distinct patterns of changes in CAC subpopulations suggest that CACs may be informative biomarkers of changes in vascular health due to tobacco product use.

The Relationship between Perceptions and Objective Measures of Greenness.

Exposure to greenness has been studied through objective measures of remote visualization of greenspace; however, the link to how individuals interpret spaces as green is missing. We examined the associations between three objective greenspace measures with perceptions of greenness. We used a subsample (n = 175; 2018-2019) from an environmental cardiovascular risk cohort to investigate perceptions of residential greenness. Participants completed a 17-item survey electronically. Objective measurements of greenness within 300 m buffer around participants home included normalized difference vegetation index (NDVI), tree canopy and leaf area index. Principal component analysis reduced the perceived greenspaces to three dimensions reflecting natural vegetation, tree cover and built greenspace such as parks. Our results suggest significant positive associations between NDVI, tree canopy and leaf area and perceived greenness reflecting playgrounds; also, associations between tree canopy and perceived greenness reflecting tree cover. These findings indicate that the most used objective greenness measure, NDVI, as well as tree canopy and leaf area may most align with perceptions of parks, whereas tree canopy alone captures individuals' perceptions of tree cover. This highlights the need for research to understand the complexity of green metrics and careful interpretation of data based on the use of subjective or objective measures of greenness.