scholarly journals Comparison of Endotoxin Exposure Assessment by Bioaerosol Impinger and Filter-Sampling Methods

2001 ◽  
Vol 67 (6) ◽  
pp. 2775-2780 ◽  
Author(s):  
Caroline Duchaine ◽  
Peter S. Thorne ◽  
Anne Mériaux ◽  
Yan Grimard ◽  
Paul Whitten ◽  
...  
Keyword(s):  
Repeated Measures ◽  
Endotoxin Concentration ◽  
Interaction Terms ◽  
Filter Methods ◽  
Endotoxin Exposure ◽  
Inhalable Dust ◽  
Acceptable Method ◽  
Swine Barns ◽  
Airborne Microorganism ◽  
Filter Sampling

ABSTRACT Environmental assessment data collected in two prior occupational hygiene studies of swine barns and sawmills allowed the comparison of concurrent, triplicate, side-by-side endotoxin measurements using air sampling filters and bioaerosol impingers. Endotoxin concentrations in impinger solutions and filter eluates were assayed using theLimulus amebocyte lysate assay. In sawmills, impinger sampling yielded significantly higher endotoxin concentration measurements and lower variances than filter sampling with IOM inhalable dust samplers. Analysis of variance for repeated measures showed that this association remained after controlling for other factors such as replicate, sawmill, sawmill operation, wood type, and interaction terms. Endotoxin concentrations in the swine barns were 10-fold higher on average than in sawmills. These samples demonstrated comparable endotoxin concentration estimates for impinger and filter methods although the variability was lower using the impinger method. In both occupational settings, side-by-side replicates were more uniform for the impinger samples than for the filter samples. This study demonstrates that impinger sampling is an acceptable method for quantitation of area endotoxin concentrations. Further, when sampling is performed with impingers for airborne microorganism quantitation, these same impinger solutions can yield valid endotoxin exposure estimates, negating the need for additional filter sampling.

scholarly journals Personal inhalable dust and endotoxin exposure among workers in an integrated textile factory

2020 ◽  
Vol 75 (7) ◽  
pp. 415-421
Author(s):  
Yifokire Tefera ◽  
Vivi Schlünssen ◽  
Abera Kumie ◽  
Wakgari Deressa ◽  
Bente E. Moen ◽  
...  
Keyword(s):  
Endotoxin Exposure ◽  
Inhalable Dust ◽  
Textile Factory

scholarly journals DNA Methylation and Asthma Acquisition During and Post-Adolescence, an Epigenome-Wide Longitudinal Study.

2021 ◽  
Author(s):  
Aniruddha Rathod ◽  
Hongmei Zhang ◽  
Hasan Arshad ◽  
Susan Ewart ◽  
Caroline Relton ◽  
...  
Keyword(s):  
Birth Cohort ◽  
Repeated Measures ◽  
Statistical Power ◽  
Transition Period ◽  
Disease Onset ◽  
Enrichment Analysis ◽  
Interaction Effects ◽  
Biological Assessment ◽  
Pathway Enrichment Analysis ◽  
Interaction Terms

Abstract Background- While the majority of asthma starts in early childhood, asthma onset in some individuals occurs during adolescence or in adulthood. However, the pathogenesis of later onset asthma as well as the observed sex specificity are not well understood. Objective- We hypothesized that DNAm at specific CpG sites measured before disease onset, either in pre- or post-adolescence would be associated with asthma acquisition both during adolescence and in later adulthood. Methods- Subjects from the Isle of Wight Birth Cohort (IOWBC) were included. DNAm in blood at ages 10 (pre-adolescence) and 18 (post-adolescence), and asthma acquisition from age 10-18, and 18-26 years was studied. To improve statistical power, we first screened epigenome-wide CpGs based on the association of DNAm at 10 years with asthma acquisition from 10-18 years. Logistic regression with repeated measures were then applied to the CpGs that survived screening to examine the associations of pre-adolescence DNAm with asthma acquisition from pre-to post-adolescence, and post-adolescence DNAm with asthma acquisition from post-adolescence to adulthood. The effect of DNAm on asthma acquisition at different transition period was evaluated using interaction terms. The ALSPAC birth cohort was used for independent replication. For biological assessment of identified CpGs, pathway enrichment analysis and Differentially Methylated Regions were assessed. Results- Significant interaction effects of DNAm and transition period (10-18 or 18-26 years) on asthma acquisition were found for 17 CpGs in males and 98 CpGs in females (FDR=0.05) in IOWBC. Consistent interaction effects were observed for 9 CpGs in males and 53 CpGs in females in ALSPAC. For CpGs not showing interaction effects (i.e., effect of DNAm is stable over time), association with asthma acquisition was found for 38 CpGs in males and 52 CpGs in females in IOWBC. Of these 90 CpGs, at 13 CpG in males and 37 CpG in females, consistent direction of associations was observed in ALSPAC. Genes that the identified CpGs were mapped to, e.g., AKAP1 and ENO1, have shown to be associated with asthma. Conclusion- DNAm at specific CpGs is associated with asthma acquisition and such association is likely to be sex and transition period specific.

A Repeated Measures Investigation of the Relation of the School Motivation Analysis Test to Academic Achievement

1973 ◽  
Vol 33 (3) ◽  
pp. 743-748 ◽  
Author(s):  
T. W. Bartsch ◽  
K. Barton ◽  
R. B. Cattell
Keyword(s):  
Social Studies ◽  
Standardized Tests ◽  
Junior High School ◽  
Repeated Measures ◽  
Differential Rate ◽  
Differential Growth ◽  
Independent Variables ◽  
Interaction Terms ◽  
Central Illinois ◽  
Main Effects

Standardized tests of social studies, science, mathematics and reading achievement, along with questionnaire measures of intelligence and motivation, were administered three times, at 6-mo. intervals, to 109 girls and 149 boys enrolled in a central Illinois junior high school. With sex, intelligence and motivation treated as independent variables, 40 repeated-measures analyses of variance were computed to determine if these factors were associated with differential rate of gain in any of the four achievement tests. Significant main effects for intelligence, motivation, and occasions were found in each analysis. In comparison, interaction terms, suggesting differential change in level of achievement, were sparse and highly specific. With one exception, it was concluded that little differential growth occurred in the sample over the 12-mo. period.

scholarly journals Inhalable dust and endotoxin exposure among Danish pig, dairy, poultry and mink farmers: results from the SUS cohort study

2011 ◽  
Vol 68 (Suppl_1) ◽  
pp. A51-A51
Author(s):  
I. Basinas ◽  
T. Sigsgaard ◽  
D. Heederik ◽  
H. Takai ◽  
O. Omland ◽  
...  
Keyword(s):  
Cohort Study ◽  
Endotoxin Exposure ◽  
Inhalable Dust

scholarly journals Pregnancy-specific transcriptional changes upon endotoxin exposure in mice

2020 ◽  
Vol 48 (7) ◽  
pp. 700-722
Author(s):  
Kenichiro Motomura ◽  
Roberto Romero ◽  
Adi L. Tarca ◽  
Jose Galaz ◽  
Gaurav Bhatti ◽  
...  
Keyword(s):  
Adrenal Gland ◽  
Host Response ◽  
Linear Models ◽  
Principal Component ◽  
Host Responses ◽  
Host Immune Responses ◽  
Interaction Terms ◽  
Specific Host ◽  
Endotoxin Exposure ◽  
Pregnant Mice

Abstract Objectives Pregnant women are more susceptible to certain infections; however, this increased susceptibility is not fully understood. Herein, systems biology approaches were utilized to elucidate how pregnancy modulates tissue-specific host responses to a bacterial product, endotoxin. Methods Pregnant and non-pregnant mice were injected with endotoxin or saline on 16.5 days post coitum (n=8–11 per group). The uterus, cervix, liver, adrenal gland, kidney, lung, and brain were collected 12 h after injection and transcriptomes were measured using microarrays. Heatmaps and principal component analysis were used for visualization. Differentially expressed genes between groups were assessed using linear models that included interaction terms to determine whether the effect of infection differed with pregnancy status. Pathway analysis was conducted to interpret gene expression changes. Results We report herein a multi-organ atlas of the transcript perturbations in pregnant and non-pregnant mice in response to endotoxin. Pregnancy strongly modified the host responses to endotoxin in the uterus, cervix, and liver. In contrast, pregnancy had a milder effect on the host response to endotoxin in the adrenal gland, lung, and kidney. However, pregnancy did not drastically affect the host response to endotoxin in the brain. Conclusions Pregnancy imprints organ-specific host immune responses upon endotoxin exposure. These findings provide insight into the host-response against microbes during pregnancy.

scholarly journals A Resourceful Work Environment Moderates the Relationship between Presenteeism and Health. A Study Using Repeated Measures in the Swedish Working Population

2020 ◽  
Vol 17 (13) ◽  
pp. 4711 ◽  
Author(s):  
Gunnar Bergström ◽  
Klas Gustafsson ◽  
Emmanuel Aboagye ◽  
Staffan Marklund ◽  
Gunnar Aronsson ◽  
...  
Keyword(s):  
Work Environment ◽  
Repeated Measures ◽  
General Health ◽  
Job Strain ◽  
Negative Impact ◽  
Psychosocial Work Environment ◽  
Psychosocial Work ◽  
Job Support ◽  
Interaction Terms ◽  
The Relationship

The objective of this study was to investigate if the psychosocial work environment moderates the proposed negative impact of presenteeism on future general health. We expect that the negative impact of presenteeism on general health is weaker if the psychosocial work environment is resourceful, and more pronounced if the environment is stressful. Data were derived from the 2008–2018 biennial waves of the Swedish Longitudinal Occupational Survey of Health (SLOSH). The final analytic sample consisted of n = 15,779 individuals. We applied repeated measures regression analyses through generalized estimating equations (GEE). Results from the autoregressive GEE models showed statistically significant interaction terms between presenteeism and all four investigated moderators, i.e., job demands, job control, job support and job strain. The results indicate that the psychosocial work environment moderates the negative association between presenteeism and general health and illustrates a buffering effect of the psychosocial work environment. A possible explanation for these results may be that psychosocially resourceful work environments give room for adjustments in the work situation and facilitate recovery. The results also indicate that by investing the psychosocial work environment employers may be able to promote worker health as well as prevent reduced job performance due to presenteeism.

scholarly journals Optimization of Airborne Endotoxin Exposure Assessment: Effects of Filter Type, Transport Conditions, Extraction Solutions, and Storage of Samples and Extracts

2007 ◽  
Vol 73 (19) ◽  
pp. 6134-6143 ◽  
Author(s):  
Suzanne Spaan ◽  
Dick J. J. Heederik ◽  
Peter S. Thorne ◽  
Inge M. Wouters
Keyword(s):  
Glass Fiber ◽  
Exposure Assessment ◽  
Storage Temperature ◽  
Free Water ◽  
Tween 20 ◽  
Adverse Health Effects ◽  
Endotoxin Exposure ◽  
Inhalable Dust ◽  
Filter Type ◽  
And Storage

ABSTRACT Endotoxin exposure occurs in homes and occupational environments and is known to cause adverse health effects. In order to compare results from different studies and establish standards, airborne endotoxin exposures should be assessed using standardized methods. Although the European Committee for Standardization (CEN) developed guidelines for endotoxin exposure assessment, these leave room for individual interpretation. The influence of methods of sampling, extraction, and analysis has never been investigated in a full experimental design. Thus, we sought to fully elucidate the importance of all facets of endotoxin assessment. Inhalable dust samples collected simultaneously were used to investigate the effects on and interactions with airborne endotoxin concentration in two working environments of filter type (glass fiber or Teflon), transport conditions (with/without desiccant), sample storage (−20 or 4°C), extraction solution (pyrogen-free water [PFW] or PFW plus 0.05% Tween 20), extract storage (−20 or 4°C), and assay solution (PFW or PFW plus 0.05% Tween 20). Four hundred samples were collected and randomly distributed over the 20 combinations of treatments. There were no differences found for transport conditions and storage temperature of extracts. Also, no interactions between study variables existed. Sampling on glass-fiber filters, storage of samples in the freezer, and extraction in PFW plus 0.05% Tween 20 resulted in 1.3-, 1.1-, and 2.1-fold-higher estimated endotoxin concentrations, respectively. Use of PFW plus 0.05% Tween 20 in the assay solution had an additive effect. Thus, this study investigated gaps in the CEN protocol and provides data with which to fully specify a protocol for standardization of endotoxin exposure assessment.

The Effect of Kalman-Weighted Averaging and Artifact Rejection on Residual Noise During Auditory Brainstem Response Testing

2019 ◽  
Vol 28 (1) ◽  
pp. 114-124
Author(s):  
Linda W. Norrix ◽  
Julie Thein ◽  
David Velenovsky
Keyword(s):  
Repeated Measures ◽  
Auditory Brainstem ◽  
Weighted Averaging ◽  
Auditory Brainstem Responses ◽  
Residual Noise ◽  
Electrophysiological Recordings ◽  
Artifact Rejection ◽  
Brainstem Response ◽  
Active Motor ◽  
Averaging Time

Purpose Low residual noise (RN) levels are critically important when obtaining electrophysiological recordings of threshold auditory brainstem responses. In this study, we examine the effectiveness and efficiency of Kalman-weighted averaging (KWA) implemented on the Vivosonic Integrity System and artifact rejection (AR) implemented on the Intelligent Hearing Systems SmartEP system for obtaining low RN levels. Method Sixteen adults participated. Electrophysiological measures were obtained using simultaneous recordings by the Vivosonic and Intelligent Hearing Systems for subjects in 2 relaxed conditions and 4 active motor conditions. Three averaging times were used for the relaxed states (1, 1.5, and 3 min) and for the active states (1.5, 3, and 6 min). Repeated-measures analyses of variance were used to examine RN levels as a function of noise reduction strategy (i.e., KWA, AR) and averaging time. Results Lower RN levels were obtained using KWA than AR in both the relaxed and active motor states. Thus, KWA was more effective than was AR under the conditions examined in this study. Using KWA, approximately 3 min of averaging was needed in the relaxed condition to obtain an average RN level of 0.025 μV. In contrast, in the active motor conditions, approximately 6 min of averaging was required using KWA. Mean RN levels of 0.025 μV were not attained using AR. Conclusions When patients are not physiologically quiet, low RN levels are more likely to be obtained and more efficiently obtained using KWA than AR. However, even when using KWA, in active motor states, 6 min of averaging or more may be required to obtain threshold responses. Averaging time needed and whether a low RN level can be attained will depend on the level of motor activity exhibited by the patient.

Vestibular Function and Motion Sickness Susceptibility: Videonystagmographic Evidence From Oculomotor and Caloric Tests

2020 ◽  
Vol 29 (2) ◽  
pp. 188-198
Author(s):  
Cynthia G. Fowler ◽  
Margaret Dallapiazza ◽  
Kathleen Talbot Hadsell
Keyword(s):  
Phase Velocity ◽  
Motion Sickness ◽  
Repeated Measures ◽  
Short Form ◽  
Vestibular Function ◽  
Slow Phase ◽  
Test Results ◽  
Normal Range ◽  
Slow Phase Velocity ◽  
Caloric Tests

Purpose Motion sickness (MS) is a common condition that affects millions of individuals. Although the condition is common and can be debilitating, little research has focused on the vestibular function associated with susceptibility to MS. One causal theory of MS is an asymmetry of vestibular function within or between ears. The purposes of this study, therefore, were (a) to determine if the vestibular system (oculomotor and caloric tests) in videonystagmography (VNG) is associated with susceptibility to MS and (b) to determine if these tests support the theory of an asymmetry between ears associated with MS susceptibility. Method VNG was used to measure oculomotor and caloric responses. Fifty young adults were recruited; 50 completed the oculomotor tests, and 31 completed the four caloric irrigations. MS susceptibility was evaluated with the Motion Sickness Susceptibility Questionnaire–Short Form; in this study, percent susceptibility ranged from 0% to 100% in the participants. Participants were divided into three susceptibility groups (Low, Mid, and High). Repeated-measures analyses of variance and pairwise comparisons determined significance among the groups on the VNG test results. Results Oculomotor test results revealed no significant differences among the MS susceptibility groups. Caloric stimuli elicited responses that were correlated positively with susceptibility to MS. Slow-phase velocity was slowest in the Low MS group compared to the Mid and High groups. There was no significant asymmetry between ears in any of the groups. Conclusions MS susceptibility was significantly and positively correlated with caloric slow-phase velocity. Although asymmetries between ears are purported to be associated with MS, asymmetries were not evident. Susceptibility to MS may contribute to interindividual variability of caloric responses within the normal range.

Effects of Aging on the Subcortical Encoding of Stop Consonants

2020 ◽  
Vol 29 (3) ◽  
pp. 391-403
Author(s):  
Dania Rishiq ◽  
Ashley Harkrider ◽  
Cary Springer ◽  
Mark Hedrick
Keyword(s):  
Older Adults ◽  
Repeated Measures ◽  
Mixed Model ◽  
Auditory Brainstem ◽  
Auditory Brainstem Responses ◽  
Aging Effects ◽  
Formant Frequency ◽  
Place Of Articulation ◽  
Second Formant ◽  
Effects Of Aging

Purpose The main purpose of this study was to evaluate aging effects on the predominantly subcortical (brainstem) encoding of the second-formant frequency transition, an essential acoustic cue for perceiving place of articulation. Method Synthetic consonant–vowel syllables varying in second-formant onset frequency (i.e., /ba/, /da/, and /ga/ stimuli) were used to elicit speech-evoked auditory brainstem responses (speech-ABRs) in 16 young adults ( M age = 21 years) and 11 older adults ( M age = 59 years). Repeated-measures mixed-model analyses of variance were performed on the latencies and amplitudes of the speech-ABR peaks. Fixed factors were phoneme (repeated measures on three levels: /b/ vs. /d/ vs. /g/) and age (two levels: young vs. older). Results Speech-ABR differences were observed between the two groups (young vs. older adults). Specifically, older listeners showed generalized amplitude reductions for onset and major peaks. Significant Phoneme × Group interactions were not observed. Conclusions Results showed aging effects in speech-ABR amplitudes that may reflect diminished subcortical encoding of consonants in older listeners. These aging effects were not phoneme dependent as observed using the statistical methods of this study.

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