scholarly journals Aerosolization of Mycobacterium tuberculosis by tidal breathing

2021 ◽  
Author(s):  
Ryan Dinkele ◽  
Sophia Gessner ◽  
Andrea McKerry ◽  
Bryan Leonard ◽  
Juane Leukes ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Particulate Matter ◽  
Real Time ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Significant Contribution ◽  
Causative Organism ◽  
Tidal Breathing ◽  
Proxy Measure ◽  
Particle Counts

Rationale: Interrupting tuberculosis (TB) transmission requires an improved understanding of how - and when - the causative organism, Mycobacterium tuberculosis (Mtb), is aerosolized. Although Cough is commonly assumed to be the dominant source of Mtb aerosols, recent evidence of Cough-independent Mtb release implies the contribution of alternative mechanisms. Objective: To compare the aerosolization of Mtb and particulate matter from GeneXpert-positive patients during three separate respiratory manoeuvres: Tidal Breathing (TiBr), Forced Vital Capacity (FVC), and Cough. Methodology: Bioaerosol sampling and Mtb detection were combined with real-time assessments of CO2 production and particle counts from 39 confirmed TB patients. Measurements and Main Results: TiBr and FVC produced comparable numbers of particles, with Cough producing >4-fold more. For all manoeuvres, the proportions of particles detected across size categories from 0.5 - 5 µm were similar, with minor differences observed only in particles between 1.5 - 2 µm (p = 0.014) and >5 µm (p = 0.020). Viable Mtb bacilli were detected in 66%, 70%, and 65% of TiBr, FVC, and Cough samples, respectively. Notably, while Cough produced 3-fold more Mtb than TiBr, the relative infrequency of coughing compared to breathing implies that TiBr likely contributes >90% of the daily aerosolised Mtb across a range of Cough frequencies. Conclusions: Our results suggest that, while Cough increases particle aerosolization compared to TiBr, this is not associated with increased Mtb aerosolization. Instead, TiBr produces more Mtb per particle than Cough. Assuming the number of viable Mtb organisms detected provides a proxy measure of patient infectiousness, these observations imply a significant contribution of TiBr to TB transmission.

Gravity effects on regional lung ventilation determined by functional EIT during parabolic flights

2001 ◽  
Vol 91 (1) ◽  
pp. 39-50 ◽  
Author(s):  
Inéz Frerichs ◽  
Taras Dudykevych ◽  
José Hinz ◽  
Marc Bodenstein ◽  
Günter Hahn ◽  
...  
Keyword(s):  
Lung Volume ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Lung Ventilation ◽  
Tidal Breathing ◽  
Parabolic Flights ◽  
Regional Lung ◽  
Residual Capacity ◽  
The Right ◽  
Regional Lung Ventilation

Gravity-dependent changes of regional lung function were studied during normogravity, hypergravity, and microgravity induced by parabolic flights. Seven healthy subjects were followed in the right lateral and supine postures during tidal breathing, forced vital capacity, and slow expiratory vital capacity maneuvers. Regional 1) lung ventilation, 2) lung volumes, and 3) lung emptying behavior were studied in a transverse thoracic plane by functional electrical impedance tomography (EIT). The results showed gravity-dependent changes of regional lung ventilation parameters. A significant effect of gravity on regional functional residual capacity with a rapid lung volume redistribution during the gravity transition phases was established. The most homogeneous functional residual capacity distribution was found at microgravity. During vital capacity and forced vital capacity in the right lateral posture, the decrease in lung volume on expiration was larger in the right lung region at all gravity phases. During tidal breathing, the differences in ventilation magnitudes between the right and left lung regions were not significant in either posture or gravity phase. A significant nonlinearity of lung emptying was determined at normogravity and hypergravity. The pattern of lung emptying was homogeneous during microgravity.

Quantifying Vocal Power: Correlation of Whole-Body Anaerobic Power to Vocal Function Measures

2020 ◽  
Vol 63 (8) ◽  
pp. 2597-2608
Author(s):  
Emily N. Snell ◽  
Laura W. Plexico ◽  
Aurora J. Weaver ◽  
Mary J. Sandage
Keyword(s):  
Fundamental Frequency ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Anaerobic Power ◽  
Performance Outcomes ◽  
Sound Level ◽  
Whole Body ◽  
Vocal Function ◽  
Laryngeal Diadochokinesis ◽  
High Sound

Purpose The purpose of this preliminary study was to identify a vocal task that could be used as a clinical indicator of the vocal aptitude or vocal fitness required for vocally demanding occupations in a manner similar to that of the anaerobic power tests commonly used in exercise science. Performance outcomes for vocal tasks that require rapid acceleration and high force production may be useful as an indirect indicator of muscle fiber complement and bioenergetic fitness of the larynx, an organ that is difficult to study directly. Method Sixteen women (age range: 19–24 years, M age = 22 years) were consented for participation and completed the following performance measures: forced vital capacity, three adapted vocal function tasks, and the horizontal sprint test. Results Using a within-participant correlational analyses, results indicated a positive relationship between the rate of the last second of a laryngeal diadochokinesis task that was produced at a high fundamental frequency/high sound level and anaerobic power. Forced vital capacity was not correlated with any of the vocal function tasks. Conclusions These preliminary results indicate that aspects of the laryngeal diadochokinesis task produced at a high fundamental frequency and high sound level may be useful as an ecologically valid measure of vocal power ability. Quantification of vocal power ability may be useful as a vocal fitness assessment or as an outcome measure for voice rehabilitation and habilitation for patients with vocally demanding jobs.

Analysis of patients with idiopathic pulmonary fibrosis (IPF) with percent predicted forced vital capacity (FVC) < 50% treated with pirfenidone in RECAP

Pneumologie ◽  
2017 ◽  
Vol 71 (S 01) ◽  
pp. S1-S125
Author(s):  
U Costabel ◽  
C Albera ◽  
KU Kirchgaessler ◽  
F Gilberg ◽  
U Petzinger ◽  
...  
Keyword(s):  
Idiopathic Pulmonary Fibrosis ◽  
Pulmonary Fibrosis ◽  
Forced Vital Capacity ◽  
Vital Capacity

Assessment of factors affecting short-term pulmonary functions following cardiac surgery: A prospective observational study

2021 ◽  
pp. 021849232110100
Author(s):  
Neetika Katiyar ◽  
Sandeep Negi ◽  
Sunder Lal Negi ◽  
Goverdhan Dutt Puri ◽  
Shyam Kumar Singh Thingnam
Keyword(s):  
Cardiac Surgery ◽  
Pulmonary Function ◽  
Forced Vital Capacity ◽  
Vital Capacity ◽  
Forced Expiratory Volume ◽  
Pulmonary Complications ◽  
Operative Morbidity ◽  
Factors Affecting ◽  
Factors Influencing ◽  
Significant Impairment

Background Pulmonary complications after cardiac surgery are very common and lead to an increased incidence of post-operative morbidity and mortality. Several factors, either modifiable or non-modifiable, may contribute to the associated unfavorable consequences related to pulmonary function. This study was aimed to investigate the degree of alteration and factors influencing pulmonary function (forced expiratory volume in one second (FEV1) and forced vital capacity), on third, fifth, and seventh post-operative days following cardiac surgery. Methods This study was executed in 71 patients who underwent on-pump cardiac surgery. Pulmonary function was assessed before surgery and on the third, fifth, and seventh post-operative days. Data including surgical details, information about risk factors, and assessment of pulmonary function were obtained. Results The FEV1 and forced vital capacity were significantly impaired on post-operative days 3, 5, and 7 compared to pre-operative values. The reduction in FEV1 was 41%, 29%, and 16% and in forced vital capacity was 42%, 29%, and 19% consecutively on post-operative days 3, 5, and 7. Multivariate analysis was done to detect the factors influencing post-operative FEV1 and forced vital capacity. Discussion This study observed a significant impairment in FEV1 and forced vital capacity, which did not completely recover by the seventh post-operative day. Different factors affecting post-operative FEV1 and forced vital capacity were pre-operative FEV1, age ≥60, less body surface area, lower pre-operative chest expansion at the axillary level, and having more duration of cardiopulmonary bypass during surgery. Presence of these factors enhances the chance of developing post-operative pulmonary complications.

Real‐time air monitoring of occupational exposures to particulate matter among hairdressers in Maryland: A pilot study

Indoor Air ◽  
2021 ◽  
Author(s):  
Yuan Shao ◽  
Lucy Kavi ◽  
Meleah Boyle ◽  
Lydia M. Louis ◽  
Walkiria Pool ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Pilot Study ◽  
Real Time ◽  
Occupational Exposures ◽  
Air Monitoring

scholarly journals Exposure to Atmospheric Particulate Matter-Bound Polycyclic Aromatic Hydrocarbons and Their Health Effects: A Review

2021 ◽  
Vol 18 (4) ◽  
pp. 2177
Author(s):  
Lu Yang ◽  
Hao Zhang ◽  
Xuan Zhang ◽  
Wanli Xing ◽  
Yan Wang ◽  
...  
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Particulate Matter ◽  
Real Time ◽  
Health Effects ◽  
Aromatic Hydrocarbons ◽  
Anthropogenic Activities ◽  
Personal Exposure ◽  
Epidemiological Studies ◽  
Atmospheric Particulate Matter ◽  
Polycyclic Aromatic

Particulate matter (PM) is a major factor contributing to air quality deterioration that enters the atmosphere as a consequence of various natural and anthropogenic activities. In PM, polycyclic aromatic hydrocarbons (PAHs) represent a class of organic chemicals with at least two aromatic rings that are mainly directly emitted via the incomplete combustion of various organic materials. Numerous toxicological and epidemiological studies have proven adverse links between exposure to particulate matter-bound (PM-bound) PAHs and human health due to their carcinogenicity and mutagenicity. Among human exposure routes, inhalation is the main pathway regarding PM-bound PAHs in the atmosphere. Moreover, the concentrations of PM-bound PAHs differ among people, microenvironments and areas. Hence, understanding the behaviour of PM-bound PAHs in the atmosphere is crucial. However, because current techniques hardly monitor PAHs in real-time, timely feedback on PAHs including the characteristics of their concentration and composition, is not obtained via real-time analysis methods. Therefore, in this review, we summarize personal exposure, and indoor and outdoor PM-bound PAH concentrations for different participants, spaces, and cities worldwide in recent years. The main aims are to clarify the characteristics of PM-bound PAHs under different exposure conditions, in addition to the health effects and assessment methods of PAHs.

Assessing reinforcing versus aversive consequences in a real-time secondhand smoke intervention

2021 ◽  
Author(s):  
Vincent Berardi ◽  
John Bellettiere ◽  
Benjamin Nguyen ◽  
Neil E Klepeis ◽  
Suzanne C Hughes ◽  
...  
Keyword(s):  
Real Time ◽  
Real World ◽  
Secondhand Smoke ◽  
Relative Effectiveness ◽  
Feedback System ◽  
Control Group ◽  
Sensing Technology ◽  
Control Versus ◽  
Particle Counts ◽  
Post Hoc

Abstract Few studies have examined the relative effectiveness of reinforcing versus aversive consequences at changing behavior in real-world environments. Real-time sensing devices makes it easier to investigate such questions, offering the potential to improve both intervention outcomes and theory. This research aims to describe the development of a real-time, operant theory-based secondhand smoke (SHS) intervention and compare the efficacy of aversive versus aversive plus reinforcement contingency systems. Indoor air particle monitors were placed in the households of 253 smokers for approximately three months. Participants were assigned to a measurement-only control group (N = 129) or one of the following groups: 1.) aversive only (AO, N = 71), with aversive audio/visual consequences triggered by the detection of elevated air particle measurements, or 2.) aversive plus reinforcement (AP, N = 53), with reinforcing consequences contingent on the absence of SHS added to the AO intervention. Residualized change ANCOVA analysis compared particle concentrations over time and across groups. Post-hoc pairwise comparisons were also performed. After controlling for Baseline, Post-Baseline daily particle counts (F = 6.42, p = 0.002), % of time &gt;15,000 counts (F = 7.72, p &lt; 0.001), and daily particle events (F = 4.04, p = 0.02) significantly differed by study group. Nearly all control versus AO/AP pair-wise comparisons were statistically significant. No significant differences were found for AO versus AP groups. The aversive feedback system reduced SHS, but adding reinforcing consequences did not further improve outcomes. The complexity of real-world environments requires the nuances of these two contingency systems continue to be explored, with this study demonstrating that real-time sensing technology can serve as a platform for such research.

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