Energetic and Cognitive Demands of Treading Water: Effects of Technique and Expertise.

Being able to tread water effectively can improve the likelihood of survival following accidental immersion. People tread water in various ways, ranging from rudimentary 'doggy-paddle' to more elaborate techniques like the eggbeater, but little is known about the energetic and cognitive requirements of treading water. We therefore aimed to measure the demands of treading water techniques for people of different experience levels. Three cohorts, comprising 21 adult water treading experts (water polo players), 15 intermediate swimmers and 16 inexperienced swimmers, treaded water for 3 min each using four different techniques while cognitive and energetic economy measures were taken. For inexperienced swimmers, the flutter kick and breaststroke patterns produced the lowest self-reported physical and task load (rating of perceived exertion, NASA task load index), while cognitive (probe reaction time), cardiac (heart rate) and metabolic (oxygen consumption) load did not differ between techniques. In contrast, for expert water treaders, both breaststroke and eggbeater patterns produced lower cognitive, cardiac and metabolic loads. For intermediate swimmers, breaststroke resulted in the lowest cardiac and metabolic loads, as well as self-reported task load. Probe reaction time was highest while performing the eggbeater technique, indicating that this technique was challenging to coordinate and cognitively demanding. While the energetic demands of antiphase kicking patterns (such as eggbeater in experts or flutter kick in beginners) may be similarly low, the symmetric coordination of upright breaststroke may explain why this pattern's cognitive economy was favourable for all groups. As the eggbeater can be challenging to perform for many people, an upright breaststroke technique is an adequate alternative to adopt in survival situations.

Genome-wide analysis of mitochondrial DNA copy number reveals loci implicated in nucleotide metabolism, platelet activation, and megakaryocyte proliferation.

Mitochondrial DNA copy number (mtDNA-CN) measured from blood specimens is a minimally invasive marker of mitochondrial function that exhibits both inter-individual and intercellular variation. To identify genes involved in regulating mitochondrial function, we performed a genome-wide association study (GWAS) in 465,809 White individuals from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium and the UK Biobank (UKB). We identified 133 SNPs with statistically significant, independent effects associated with mtDNA-CN across 100 loci. A combination of fine-mapping, variant annotation, and co-localization analyses was used to prioritize genes within each of the 133 independent sites. Putative causal genes were enriched for known mitochondrial DNA depletion syndromes (p = 3.09 × 10-15) and the gene ontology (GO) terms for mtDNA metabolism (p = 1.43 × 10-8) and mtDNA replication (p = 1.2 × 10-7). A clustering approach leveraged pleiotropy between mtDNA-CN associated SNPs and 41 mtDNA-CN associated phenotypes to identify functional domains, revealing three distinct groups, including platelet activation, megakaryocyte proliferation, and mtDNA metabolism. Finally, using mitochondrial SNPs, we establish causal relationships between mitochondrial function and a variety of blood cell-related traits, kidney function, liver function and overall (p = 0.044) and non-cancer mortality (p = 6.56 × 10-4).

Genotypic variation and covariation in wheat seedling seminal root architecture and grain yield under field conditions.

KEY MESSAGE: Greater embryo size in a large and carefully phenotyped mapping population was genetically associated with a greater number of longer seminal roots to increase grain yield in droughted field environments. Breeding modification of root architecture is challenging in field environments owing to genetic and phenotypic complexity, and poor repeatability with root sampling. Seeds from a large mapping population varying in embryo size were harvested from a common glasshouse and standardised to a common size before assessing in rolled germination paper at 12 and 20 °C for seedling growth. Differences in genotype means were large and heritabilities high (h2 = 0.55-0.93) indicating strong and repeatable genotypic differences for most root traits. Seminal roots 1 to 3 were produced on all seedlings, whereas growth of seminal roots 4, 5 and 6 was associated with differences in embryo size. Increases in seminal root number from 4 to 6 per plant were strongly, genetically correlated with increases in total seminal length (rg = 0.84, < 0.01). Multivariate analysis confirmed initiation and growth of seminal roots 1, 2 and 3, and of roots 4, 5 and 6 behaved as genetically independent (rPg = 0.15 ns) cohorts. Tails representing extremes in seedling root length and number were associated with significant differences in grain yield of up to 35% in droughted field environments but were not different in irrigated environments. Increases in grain yield were linked to greater lengths of seminal roots 4, 5 and 6 and were largely independent of plant height or development. This is the first report on the genetic relationship of seedling root architecture and embryo size, and potential in selection of seminal root size for accessing deep-soil moisture in droughted environments.

The Rowing-Specific Reinvestment Scale.

This research project aimed to develop and validate a rowing-specific reinvestment scale. In Study 1, a 24-item questionnaire was developed and the content validity was assessed using experts (N = 7) and pilot-tested in rowers (N = 24). Next, rowers (N = 282) completed the questionnaire with the remaining items, and exploratory factor analysis (EFA) was conducted. This further reduced the number of items and revealed two factors, rowing specific conscious motor processing (RS-CMP) and movement self-consciousness (RS-MSC). In Study 2, rowers (N = 270) completed the scale that was evaluated using confirmatory factor analysis (CFA). Moreover, the construct validity of the scale was investigated by asking them to complete measures of movement-specific reinvestment, perceived performance, self-consciousness, and state anxiety. Actual performance was also determined based on their race finishing position. Study 1 EFA resulted in a 2-factor model with six items assessing RS-CMP and six items assessing RS-MSC. Study 2 supported the factor structure of scale; CFA indicated an acceptable model fit with good internal consistency. Content validity was also supported, with evidence of concurrent, convergent, discriminant, and predictive validity. In conclusion, these studies provided good initial evidence for the validity and reliability of the RSRS.

StomataCounter: a neural network for automatic stomata identification and counting.

Stomata regulate important physiological processes in plants and are often phenotyped by researchers in diverse fields of plant biology. Currently, there are no user-friendly, fully automated methods to perform the task of identifying and counting stomata, and stomata density is generally estimated by manually counting stomata. We introduce StomataCounter, an automated stomata counting system using a deep convolutional neural network to identify stomata in a variety of different microscopic images. We use a human-in-the-loop approach to train and refine a neural network on a taxonomically diverse collection of microscopic images. Our network achieves 98.1% identification accuracy on Ginkgo scanning electron microscropy micrographs, and 94.2% transfer accuracy when tested on untrained species. To facilitate adoption of the method, we provide the method in a publicly available website at http://www.stomata.science/.

Associations between antibiotic prescriptions and recurrent urinary tract infections in female college students.

Urinary tract infections (UTIs) are common among college-aged women and often recur. Some antibiotics recommended to treat UTIs trigger dysbiosis of intestinal and vaginal microbiomes - where uropathogens originate, though few studies have investigated associations between these therapies with recurrent infections. We retrospectively analysed the electronic medical records of 6651 college-aged women diagnosed with a UTI at a US university student health centre between 2006 and 2014. Women were followed for 6 months for incidence of a recurrent infection. In a secondary analysis, associations in women whose experienced UTI recurrence within 2 weeks were also considered for potential infection relapse. Logistic regression was used to assess associations between infection recurrence or relapse and antibiotics prescribed, in addition to baseline patient characteristics including age, race/ethnicity, region of origin, year of encounter, presence of symptomology, pyelonephritis, vaginal coinfection and birth control consultation. There were 1051 instances of infection recurrence among the 6620 patients, indicating a prevalence of 16%. In the analysis of patient characteristics, Asian women were statistically more likely to experience infection recurrence whereas African American were less likely. No significant associations were identified between the antibiotic administered at the initial infection and the risk of infection recurrence after multivariable adjustment. Treatment with trimethoprim-sulphamethoxazole and being born outside of the USA were significantly associated with increased odds of infection relapse in the multivariate analysis. The results of the analyses suggest that treatment with trimethoprim-sulphamethoxazole may lead to an increased risk of UTI relapse, warranting further study.

Investigating Changes in Real-time Conscious Postural Processing by Older Adults during Different Stance Positions Using Electroencephalography Coherence.

Background/Study Context: Adjustments of posture in response to balance challenges may lead to subsequent increases in conscious posture processing. If cognitive resources are stretched by conscious processing of postural responses fewer resources will be available to attend to environmental trip or fall hazards. The objective of the study was to explore brain activity related to conscious processing of posture as a function of movement specific reinvestment and fear of falling. Method: Forty-three older adults (M = 71.4, SD = 4.1) stood with a wide or narrow stance on a force-plate while neural coherence between verbal-analytical (T3) and motor planning (Fz) regions of the brain was assessed using electroencephalography. The propensity for movement specific reinvestment was assessed using the Chinese version Movement Specific Reinvestment Scale (MSRS-C) and fear of falling was assessed using the Chinese version Fall Efficacy Scale International (FES-I[CH]). Results: Scores from the MSRS-C were negatively correlated with changes in T3-Fz coherence that occurred when participants shifted from wide to narrow stance. Together, MSRS-C and FES-I(CH) uniquely predicted the percentage change in T3-Fz coherence between the two stance conditions. Conclusion: Presented with two postural tasks of different complexities, participants with a lower propensity for conscious control of their movements (movement specific reinvestment) exhibited larger changes in real-time brain activity (neural coherence) associated with conscious postural processing.

Investigating an errorless learning approach for developing dental operative technique skills: A pilot study.

INTRODUCTION: Explicit instruction (conscious knowledge/rules) is generally used for learning dental operative skills; however, recent work has demonstrated advantages of learning skills implicitly with minimal accrual of conscious knowledge and reduced attentional demands. Therefore, this study examined the effects of learning handpiece manipulation skills explicitly (errorful) and implicitly (errorless: limited error detection/correction) under conditions of increased attentional demands (ie multitasking and additional instructions). MATERIALS AND METHODS: Non-dental university students were randomly assigned to errorless (n = 11) or errorful (n = 8) groups. They used pencil lead instead of a bur, with errorless learners shading shapes from simple (small circle) to complex (cross), while errorful learners shaded the shapes in reverse. During testing, they completed simulated cavities in baseline, additional instructions and multitask conditions. Learning performance was calculated as per cent of the shape shaded successfully. Test performance was computed as error in cavity length/depth and was compared with dental students who had completed their operative technique course (n = 14). RESULTS: Errorless learners were more accurate than errorful learners especially when shading difficult shapes (P = 0.042). With additional instructions, errorless and errorful learners did not differ in cavity depth (P = 0.057) or length (P = 0.540). When multitasking, errorless learners prepared the cavity length (P = 0.048) but not depth (P = 0.920) more accurately than errorful learners. Overall, performance of errorless learners was comparable to dental students. CONCLUSIONS: These preliminary findings suggest handpiece skills can be acquired implicitly via errorless learning, and it is less attentionally demanding than errorful learning, as evident by maintenance of preparation performance when processing additional relevant instructions and multitasking.

Examining links between anxiety, reinvestment and walking when talking by older adults during adaptive gait.

Falls by older adults often result in reduced quality of life and debilitating fear of further falls. Stopping walking when talking (SWWT) is a significant predictor of future falls by older adults and is thought to reflect age-related increases in attentional demands of walking. We examine whether SWWT is associated with use of explicit movement cues during locomotion, and evaluate if conscious control (i.e. movement specific reinvestment) is causally linked to fall-related anxiety during a complex walking task. We observed whether twenty-four older adults stopped walking when talking when asked a question during an adaptive gait task. After certain trials, participants completed a visuospatial recall task regarding walkway features, or answered questions about their movements during the walk. In a subsequent experimental condition, participants completed the walking task under conditions of raised postural threat. Compared to a control group, participants who SWWT reported higher scores for aspects of reinvestment relating to conscious motor processing but not movement self-consciousness. The higher scores for conscious motor processing were preserved when scores representing cognitive function were included as a covariate. There were no group differences in measures of general cognitive function, visuospatial working memory or balance confidence. However, the SWWT group reported higher scores on a test of external awareness when walking, indicating allocation of attention away from task-relevant environmental features. Under conditions of increased threat, participants self-reported significantly greater state anxiety and reinvestment and displayed more accurate responses about their movements during the task. SWWT is not associated solely with age-related cognitive decline or generic increases in age-related attentional demands of walking. SWWT may be caused by competition for phonological resources of working memory associated with consciously processing motor actions and appears to be causally linked with fall-related anxiety and increased vigilance.

Comparison of molecular detection methods for pertussis in children during a state-wide outbreak.

A state-wide pertussis outbreak occurred in Washington during the winter-spring months of 2012, concurrent with respiratory viral season. We compared performance characteristics of a laboratory-developed pertussis PCR (LD-PCR for Bordetella pertussis, Bordetella parapertussis, and Bordetella holmesii) and rapid multiplex PCR (RM-PCR) for respiratory viruses (FilmArray™, BioFire, B. pertussis data unblinded following FDA approval post outbreak). We analyzed three cohorts of patients using physician testing orders as a proxy for clinical suspicion for pertussis or respiratory viruses: Cohort 1, tested by LD-PCR for pertussis pathogens only by nasopharyngeal swab; Cohort 2, by RM-PCR for respiratory viruses only by mid-nasal turbinate swab; and Cohort 3, by both methods. B. pertussis was detected in a total of 25 of the 490 patients in Cohort 3 in which LD-PCR detected 20/25 (80 %) cases and the RM-PCR detected 24/25 (96 %; p = 0.2). Pertussis pathogens were detected in 21/584 (3.6 %) of samples from Cohort 1 where clinicians had a relatively strong suspicion for pertussis. In contrast, B. pertussis was detected in only 4/3071 (0.1 %) specimens from Cohort 2 where suspicion for pertussis was lower (p < 0.001 for comparison with Cohort 1). In summary, the two laboratory methods were comparable for the detection of B. pertussis.

Multitask training promotes automaticity of a fundamental laparoscopic skill without compromising the rate of skill learning.

BACKGROUND: A defining characteristic of expertise is automated performance of skills, which frees attentional capacity to better cope with some common intraoperative stressors. There is a paucity of research on how best to foster automated performance by surgical trainees. This study examined the use of a multitask training approach to promote automated, robust laparoscopic skills. METHODS: Eighty-one medical students completed training of a fundamental laparoscopic task in either a traditional single-task training condition or a novel multitask training condition. Following training, participants' laparoscopic performance was tested in a retention test, two stress transfer tests (distraction and time pressure) and a secondary task test, which was included to evaluate automaticity of performance. The laparoscopic task was also performed as part of a formal clinical examination (OSCE). RESULTS: The training groups did not differ in the number of trials required to reach task proficiency (p = .72), retention of skill (ps > .45), or performance in the clinical examination (p = .14); however, the groups did differ with respect to the secondary task (p = .016). The movement efficiency (number of hand movements) of single-task trainees, but not multitask trainees, was negatively affected during the secondary task test. The two stress transfer tests had no discernable impact on the performance of either training group. CONCLUSION: Multitask training was not detrimental to the rate of learning of a fundamental laparoscopic skill and added value by providing resilience in the face of a secondary task load, indicative of skill automaticity. Further work is needed to determine the extent of the clinical utility afforded by multitask training.

The Impact of Abuse Trauma on Alcohol and Drug Use: A Study of High-Risk Incarcerated Girls.

This study examines the impact of abuse trauma (physical and sexual) on alcohol and drug use of high-risk girls (12-18 years of age) who were surveyed within the first two weeks of their incarceration. One-way ANOVA analyses and Tukey post-hoc tests indicate physical abuse with a weapon was associated with higher marijuana use and number of drugs used. Sexual abuse, especially within the past year increased marijuana use, alcohol use, number of drugs used, and alcohol and other drug (AOD) problems. Policy implications reflect the need for treatment protocols within substance abuse programs to address abuse trauma, particularly, forced sex which has occurred within the last year.

Gingival bleeding on probing: relationship to change in periodontal pocket depth and effect of sodium hypochlorite oral rinse.

BACKGROUND AND OBJECTIVE: This study evaluated the potential of gingival bleeding on probing to serve as a predictor of future periodontal breakdown. It also assessed the ability of 0.25% sodium hypochlorite twice-a-week oral rinse to convert periodontal pockets showing bleeding on probing to nonbleeding sites. MATERIAL AND METHODS: The study was performed as a randomized, single-blinded, clinical trial in parallel groups. Seven periodontitis patients rinsed twice-weekly for 3 mo with 15 mL of a fresh solution of 0.25% sodium hypochlorite, and five periodontitis patients rinsed with water. The 12 study patients received no subgingival or supragingival scaling. Clorox(®) Regular-Bleach was the source of sodium hypochlorite. At baseline and 3-mo visits, gingival bleeding was assessed within 30 s after probing to full pocket depth using an approximate force of 0.75 N. RESULTS: A total of 470 (38%) of 1230 periodontal pockets in the bleach-rinse group revealed bleeding on probing at the initial visit but not at the 3-mo visit; only 71 (9%) of 828 pockets in the control group became bleeding-negative during the study (p < 0.001). Bleeding on probing in 4- to 7-mm-deep pockets decreased by 53% in the bleach-rinse group but increased by 6% in the water-rinse group (p < 0.001). Ninety-seven pockets showed depth increases of ≥ 2 mm after 3 mo: 60 (62%) of those pockets exhibited bleeding on probing at both the initial and the 3-mo visits; 24 (25%) bled at only one of the two visits; and 13 (13%) never demonstrated gingival bleeding (p < 0.001). CONCLUSIONS: Persistent gingival bleeding on probing was associated with an increased risk for periodontal breakdown, and the absence of gingival bleeding seemed to be a useful, although not perfect, indicator of disease stability. Twice-weekly oral rinsing with dilute bleach (0.25% sodium hypochlorite) produced a significant reduction in bleeding on probing, even in deep unscaled pockets. Sodium hypochlorite constitutes a valuable antiseptic in periodontal self-care.

Surgeons' display reduced mental effort and workload while performing robotically assisted surgical tasks, when compared to conventional laparoscopy.

BACKGROUND: Research has demonstrated the benefits of robotic surgery for the patient; however, research examining the benefits of robotic technology for the surgeon is limited. This study aimed to adopt validated measures of workload, mental effort, and gaze control to assess the benefits of robotic surgery for the surgeon. We predicted that the performance of surgical training tasks on a surgical robot would require lower investments of workload and mental effort, and would be accompanied by superior gaze control and better performance, when compared to conventional laparoscopy. METHODS: Thirty-two surgeons performed two trials on a ball pick-and-drop task and a rope-threading task on both robotic and laparoscopic systems. Measures of workload (the surgery task load index), mental effort (subjective: rating scale for mental effort and objective: standard deviation of beat-to-beat intervals), gaze control (using a mobile eye movement recorder), and task performance (completion time and number of errors) were recorded. RESULTS: As expected, surgeons performed both tasks more quickly and accurately (with fewer errors) on the robotic system. Self-reported measures of workload and mental effort were significantly lower on the robotic system compared to the laparoscopic system. Similarly, an objective cardiovascular measure of mental effort revealed lower investment of mental effort when using the robotic platform relative to the laparoscopic platform. Gaze control distinguished the robotic from the laparoscopic systems, but not in the predicted fashion, with the robotic system associated with poorer (more novice like) gaze control. CONCLUSIONS: The findings highlight the benefits of robotic technology for surgical operators. Specifically, they suggest that tasks can be performed more proficiently, at a lower workload, and with the investment of less mental effort, this may allow surgeons greater cognitive resources for dealing with other demands such as communication, decision-making, or periods of increased complexity in the operating room.

Examining Movement-Specific Reinvestment and Performance in Demanding Contexts.

Two experiments examined the roles of the dimensions of movement-specific reinvestment (movement self-consciousness and conscious motor processing) on performance under demanding conditions. In Experiment 1, novice golfers practiced a golf putting task and were tested under low- and high-anxiety conditions. Conscious motor processing was not associated with putting proficiency or movement variability; however, movement self-consciousness was positively associated with putting proficiency and appeared to be negatively associated with variability of impact velocity in low-anxiety conditions, but not in high-anxiety conditions. Increased anxiety and effort possibly left few attention resources for movement self-consciousness under high anxiety. In Experiment 2, participants performed a quiet standing task in single- and dual-task conditions. Movement self-consciousness was positively associated with performance when attention demands were low (single task) but not when attention demands were high (dual task). The findings provide insight into the differential influence of the two dimensions of movement-specific reinvestment under demanding conditions.

Periodontal effects of 0.25% sodium hypochlorite twice-weekly oral rinse. A pilot study.

BACKGROUND AND OBJECTIVE: The study aimed to evaluate the effect of 0.25% sodium hypochlorite twice-weekly oral rinse on plaque and gingivitis in patients with minimally treated periodontitis. MATERIAL AND METHODS: The study included 30 patients with periodontitis, it lasted 3 mo, and it was performed as a randomized, controlled, single-blinded, clinical trial in parallel groups. Fifteen patients rinsed for 30 s with 15 mL of a fresh solution of 0.25% sodium hypochlorite (test) and 15 patients rinsed with 15 mL of water (control). Clorox(®) regular bleach was the source of the sodium hypochlorite. At baseline and at 2 wk, the study patients received professional subgingival irrigation for 5 min with either 0.25% sodium hypochlorite or water, but no subgingival or supragingival scaling. The presence or absence of supragingival plaque on facial and lingual surfaces was determined by visual inspection; each tooth was dried with air and mouth mirror rotation was used to provide light reflection to identify plaque on smooth surfaces and at the tooth line angles. Gingival bleeding within 30 s after probing to full pocket depth was assessed in six sites of each tooth. Adverse events were evaluated by questionnaire and visual examination. RESULTS: All 30 patients in the study completed the baseline and the 2 wk parts of the study and a subset of 12 participants completed the 3 mo part of the study. The sodium hypochlorite rinse group and the water rinse group, respectively, showed increases from baseline to 3 mo of 94% and 29% (3.2-fold difference) in plaque-free facial surfaces, of 195% and 30% (6.5-fold difference) in plaque-free lingual surfaces, and of 421% and 29% (14.5-fold difference) in number of teeth with no bleeding on probing. The differences in clinical improvement between the sodium hypochlorite rinse group and the water rinse group were statistically significant. No adverse events were identified in any of the study patients, except for minor complaints about the taste of bleach. CONCLUSION: A twice-weekly oral rinse with 0.25% sodium hypochlorite produced marked decreases in dental plaque level and bleeding on probing and may constitute a promising new approach to the management of periodontal disease. Long-term controlled studies on the effectiveness of sodium hypochlorite oral rinse are needed and encouraged.

Scaling sporting equipment for children promotes implicit processes during performance.

This study investigated whether children who used scaled equipment compared to full size equipment during a motor task demonstrated reduced conscious involvement in performance. Children (9-11 years) performed a tennis hitting task in two attention conditions (single-task and dual-task) using two types of equipment (scaled and full size). A more skilled group and a less skilled group were formed using hitting performance scores. The more skilled group displayed greater working memory capacity than the less skilled group. For both groups, hitting performance and technique were better when scaled equipment was used. Hitting performance when using scaled equipment was not disrupted in either group by a cognitively demanding secondary task; however, performance was disrupted in the less skilled group when using full size equipment. We conclude that equipment scaling may reduce working memory engagement in motor performance and discuss the findings in the context of implicit motor learning theory.

Microbial communities within field-collected Culiseta melanura and Coquillettidia perturbans.

Although mosquitoes are well-known vectors of human and animal diseases, pathogens are only minor components of their total endogenous microbial communities. The midguts of many insects, including mosquitoes, contain diverse microbial communities. In this study, we used denaturing gradient gel electrophoresis to identify the diversity of bacteria in field-collected adult female Culiseta melanura (Diptera: Culicidae) (Coquillett) and Coquillettidia perturbans (Diptera: Culicidae) (Walker). Few significant differences in bacterial fauna between the two mosquito species were found, but the results suggest that host life history may be a determinant of the endogenous bacterial communities in mosquitoes. In the present study, the dominant bacteria are frequently identified as major components of other mosquito species' microbial flora, suggesting the establishment of a stable association between the mosquitoes and the microbes after initial acquisition from the environment.

Safe(r) landing by older people: A matter of complexity.

Maintaining balance is a complex motor problem that requires coordinated contributions from multiple biological systems. Aging inevitably lessens the fidelity of biological systems, which can result in an increased risk of falling, and associated injuries. It is advantageous to land safely, but falls manifest in diverse ways, so different motor solutions are required to land safely. However, without considerable practice, it is difficult to recall the appropriate motor solution for a fall and then apply it effectively in the brief duration before hitting the ground. A complex systems perspective provides a lens through which to view the problem of safe-landing. It may be possible to use motor analogies to promote degeneracy within the perceptual-motor system so that, regardless of the direction in which an older person falls, their body self-organizes to land with less likelihood of injury.

Adhesion molecules, endothelin-1 and lung function in seven population-based cohorts.

CONTEXT: Endothelial function is abnormal in chronic obstructive pulmonary disease (COPD); whether endothelial dysfunction causes COPD is unknown. OBJECTIVE: Test associations of endothelial biomarkers with FEV1 using instrumental variables. METHODS: Among 26 907 participants with spirometry, ICAM-1, P-selectin, E-selectin and endothelin-1 were measured in subsets. RESULTS: ICAM-1 and P-selectin were inversely associated with FEV1 among European-Americans (-29 mL and -34 mL per standard deviation of log-transformed biomarker, p < 0.001), as was endothelin-1 among African-Americans (-22 mL, p = 0.008). Genetically-estimated ICAM-1 and P-selectin were not significantly associated with FEV1. The instrumental variable for endothelin-1 was non-informative. CONCLUSION: Although ICAM-1, P-selectin and endothelin-1 were inversely associated with FEV1, associations for ICAM-1 and P-selectin do not appear causal.