ERS International Congress 2021: Highlights from the Allied Respiratory Professionals assembly

This paper provides an overview of some of the most memorable sessions that were (co)organised by the Allied Respiratory Professionals Assembly during the 2021 European Respiratory Society International Congress, which was held online for the second consecutive year due to the COVID-19 pandemic. Early Career Members from Assembly 9 summarised the content of the sessions (three oral communication sessions, two symposia and one Expert View) with the support of the chairs from the four Assembly groups: Respiratory Function Technologists and Scientists (Group 9.01); Physiotherapists (Group 9.02); Nurses (Group 9.03); and Psychologists and Behavioural Scientists (Group 9.04). The sessions covered the following topics: impact of COVID-19 on lung function and healthcare services, and the importance of quality assurance and technology in lung function assessment; diagnosis and management of sarcopenia in patients with chronic respiratory disease; maintenance of the effects of pulmonary rehabilitation; solutions outside the hospital for the management of patients with COVID-19 in need of health care; the nursing perspective during the COVID-19 pandemic; and psychological and behavioural issues in respiratory care. This highlights article provides valuable insight into the latest scientific data and emerging areas affecting clinical practice of allied respiratory professionals.

This article provides an overview of outstanding sessions that were (co)organised by @ERS_Assembly9 during #ERSCongress 2021https://bit.ly/332uZWy

The "can do, do do" concept in individuals with chronic obstructive pulmonary disease: an exploration of psychological mechanisms

Background

The “can do, do do” concept aims at identifying subgroups among persons with chronic obstructive pulmonary disease (COPD). Following a two-dimensional categorization, individuals are binarily classified with respect to their levels of physical capacity (“can’t do” or “can do”) and physical activity (“don’t do” or “do do”), resulting in four disjunct quadrants. The approach has been debated recently and the latest articles have concluded that the quadrants should be specifically examined in terms of psychological aspects of physical activity. Therefore, the goal of the present study was to explore the role of psychological variables in physical activity in the context of the “can do, do do” quadrant concept.

Methods

Within the scope of secondary data analyses of the “Stay Active After Rehabilitation” (STAR) randomized controlled trial, a total of 298 COPD rehabilitants of an inpatient pulmonary rehabilitation program were grouped into the suggested quadrants. We set fixed cut-offs at 70% of relative 6-min walking test performances for healthy individuals (physical capacity dimension) and 5.000 steps per day (physical activity dimension). Univariate and multivariate logistic regression analyses served to analyze whether depression scores, fear avoidance behaviors, disease-specific anxiety, self-concordance for physical activity, and five indicators of physical activity-related health competence (PAHCO) effectively discriminated between the “don’t do” and “do do” groups.

Results

Among persons with lower relative physical capacity, depression scores, fear avoidance behaviors, and disease-specific anxiety (univariate case) significantly differentiated between the more and the less active. Among persons with higher relative physical capacity, fear avoidance behaviors, disease-specific anxiety, as well as three PAHCO indicators (physical activity-specific self-efficacy, self-control, and affect regulation) significantly separated the more and the less active. In multivariate analyses, only fear avoidance behaviors and affect regulation discriminated among individuals with better relative physical capacity.

Conclusion

The findings identified important psychological and competence-oriented variables that explain discrepancies in the quadrant concept. Based on this, we discuss implications for physical activity promotion in individuals with COPD. Respiratory research can benefit from future studies complementing the quadrant concept through further behavioral analyses.

Trial registration Clinicaltrials.gov, ID: NCT02966561. Registered 17 November, 2016, https://clinicaltrials.gov/ct2/show/NCT02966561.

In the spotlight: first ERS Early Career Member Award winner, the ERS Lung Science Conference 2020 and new ECMC members

At the European Respiratory Society (ERS) International Congress in Paris (France) in 2018, the Early Career Members Committee (ECMC) postulated the idea of providing an incentive for ambitious and successful Early Career Members (ECMs) through granting an ECM award. The ECMC forwarded the concept to the ERS Executive Committee. ECM representatives of each assembly discussed the nomination of an ECM within each assembly. Based on their curriculum vitae and involvement within ERS, the nominees were ranked, and Lies Lahousse became the laureate of the first ERS Early Career Member Award (figure 1). Two ECMs (T. Janssens and J. De Brandt) visited Prof. Lahousse in Ghent (Belgium) to interview her.

All you need to know about @LiesLahousse, first ECM to be granted the Early Career Member Award; #LSC2020; the newly elected assembly representatives for @EarlyCareerERS; and new @EuroRespSoc fellowship opportunitieshttp://bit.ly/2OTgQlo

A43 Translational research: NGS metagenomics into clinical diagnostics

As research next-generation sequencing (NGS) metagenomic pipelines transition to clinical diagnostics, the user-base changes from bioinformaticians to biologists, medical doctors, and lab-technicians. Besides the obvious need for benchmarking and assessment of diagnostic outcomes of the pipelines and tools, other focus points remain: reproducibility, data immutability, user-friendliness, portability/scalability, privacy, and a clear audit trail. We have a research metagenomics pipeline that takes raw fastq files and produces annotated contigs, but it is too complicated for non-bioinformaticians. Here, we present preliminary findings in adapting this pipeline for clinical diagnostics. We used information available on relevant fora (www.bioinfo-core.org) and experiences and publications from colleague bioinformaticians in other institutes (COMPARE, UBC, and LUMC). From this information, a robust and user-friendly storage and analysis workflow was designed for non-bioinformaticians in a clinical setting. Via Conda [https://conda.io] and Docker containers [http://www.docker.com], we made our disparate pipeline processes self-contained and reproducible. Furthermore, we moved all pipeline settings into a separate JSON file. After every analysis, the pipeline settings and virtual-environment recipes will be archived (immutably) under a persistent unique identifier. This allows long-term precise reproducibility. Likewise, after every run the raw data and final products will be automatically archived, complying with data retention laws/guidelines. All the disparate processes in the pipeline are parallelized and automated via Snakemake1 (i.e. end-users need no coding skills). In addition, interactive web-reports such as MultiQC [http://multiqc.info] and Krona2 are generated automatically. By combining Snakemake, Conda, and containers, our pipeline is highly portable and easily scaled up for outbreak situations, or scaled down to reduce costs. Since patient privacy is a concern, our pipeline automatically removes human genetic data. Moreover, all source code will be stored on an internal Gitlab server, and, combined with the archived data, ensures a clear audit trail. Nevertheless, challenges remain: (1) reproducible reference databases, e.g. being able to revert to an older version to reproduce old analyses. (2) A user-friendly GUI. (3) Connecting the pipeline and NGS data to in-house LIMS. (4) Efficient long-term storage, e.g. lossless compression algorithms. Nevertheless, this work represents a step forward in making user-friendly clinical diagnostic workflows.

Assessment of Anterior Cruciate Ligament Graft Maturity With Conventional Magnetic Resonance Imaging: A Systematic Literature Review

Background:

Magnetic resonance imaging (MRI) signal intensity (SI) measurements are being used increasingly in both clinical and research studies to assess the maturity of anterior cruciate ligament (ACL) grafts in humans. However, SI in conventional MRI with weighted images is a nonquantitative measure dependent on hardware and software.

Purpose:

To conduct a systematic review of studies that have used MRI SI as a proxy for ACL graft maturity and to identify potential confounding factors in assessing the ACL graft in conventional MRI studies.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

A systematic review was conducted by searching the MEDLINE/PubMed, Scopus, and Cochrane Library electronic databases according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines to identify studies that examined the healing of the intra-articular portion of the ACL graft by assessing SI on MRIs.

Results:

A total of 34 studies were selected for inclusion in this systematic review. The MRI acquisition techniques and methods to evaluate the ACL graft SI differed greatly across the studies. No agreement was found regarding the time frames of SI changes in MRI reflecting normal healing of the ACL tendon graft, and the graft SI and clinical outcomes after ACL reconstruction were found to be poorly correlated.

Conclusion:

The MRI acquisition and evaluation methods used to assess ACL grafts are very heterogeneous, impeding comparisons of SI between successive scans and between independent studies. Therefore, quantitative MRI-based biomarkers of ACL graft healing are greatly needed to guide the appropriate time of returning to sports after ACL reconstruction.

Placebo and nocebo effects and operant pain-related avoidance learning

INTRODUCTION

Research on learning in placebo and nocebo has relied predominantly on Pavlovian conditioning procedures. Operant learning procedures may more accurately model learning in real-life situations in which placebo and nocebo effects occur.

OBJECTIVES

To investigate the development and persistence of placebo and nocebo effects using an operant avoidance learning task.

METHODS

Pain-free participants (n = 58) could learn to avoid pain by performing movements that differed in difficulty and intensity of painful stimulation. Participants performed movements in 2 contexts. In the high cost of avoidance context, pain stimulus intensity reduced with increasing movement difficulty. In the low cost of avoidance context, contingencies were reversed. Participants rated pain expectations and pain intensity. During test, movement difficulties were unchanged, but participants always received a medium-intensity pain stimulus. Placebo and nocebo effects were defined as lower/higher pain intensity ratings for trajectories that previously resulted in low/high-intensity compared with medium-intensity stimulation.

RESULTS

As expected, participants acquired differential movement-pain expectations and differential movement choices. Testing with a medium-intensity pain stimulus quickly erased differences in movement choice across contexts, but differences in pain expectations were maintained. Pain modulation across context was in line with movement-pain expectations. However, we only observed placebo effects within the low cost of avoidance context and found no evidence of nocebo effects.

CONCLUSION

Operant learning can change pain expectations, pain modulation, and pain-related avoidance behavior. Persisting pain expectations suggest that acquired pain beliefs may be resistant to disconfirmation, despite self-initiated experience with novel pain-movement contingencies.

Influence of incubation conditions on the formation of model biofilms by Listeria monocytogenes and Salmonella Typhimurium on abiotic surfaces

AIMS

This research aims to develop strongly adherent and mature model biofilms (on a 20 cm² polystyrene surface) for two pathogenic species, i.e. Listeria monocytogenes and Salmonella Typhimurium. These model biofilms can be used as standards to study biofilms or to study/compare the influence of different inactivation technologies.

METHODS AND RESULTS

Three influencing factors on the formation of biofilms are investigated, i.e. growth medium, incubation temperature and incubation time, which are three easily controllable environmental factors. Optical density measurement and plate counts were used to evaluate the adherence and the maturity of the biofilms, respectively. Confocal laser scanning microscopy was used to verify most important findings obtained with previously mentioned assays. Results indicated that mature and strongly adherent L. monocytogenes biofilms are obtained following 13 h of incubation at 30°C with BHI as growth medium. For S. Typhimurium, an incubation period of 19 h at 25°C was required with 20-fold diluted TSB as growth medium.

CONCLUSIONS

Based on previously mentioned assays, a protocol for the formation of reproducible model biofilms was obtained.

SIGNIFICANCE AND IMPACT OF THE STUDY

The developed model biofilms can be applied as a standard to study biofilms (in different research fields) and their subsequent inactivation by different methods. In addition, the results of this study could be used to control biofilm formation (e.g. by setting a maximum allowed surface temperature).

Towards an assessment of perceived COPD exacerbation triggers: Initial development and validation of a questionnaire

BACKGROUND AND OBJECTIVE

Prevention of exacerbations in chronic obstructive pulmonary disease (COPD) is important to decrease overall declines in functioning and improve quality of life. The present study sought to develop a psychometrically valid measure of perceived triggers of exacerbations in COPD patients, the COPD Exacerbation Trigger Inventory (CETI).

METHODS

Participants (n = 192) were recruited through local clinics and online to complete surveys of the CETI, demographic information, disease-specific information and the COPD Assessment Test (CAT). The CETI included a free response section on patients' individual top triggers, combined with ratings of their controllability.

RESULTS

Exploratory principal component analyses identified a stable 5-factor structure (33 items), from which trigger subscales for weather/climate, air pollution/irritants, exercise, infection/illness and psychological factors were formed (internal consistency Cronbach's α = 0.90-0.94). Trigger factors were associated with COPD functional status, exacerbation frequency and healthcare utilization. Participants found personal triggers related to dust, air pollution, smoking and physical activity to be the most easily controlled, whereas those related to psychological factors, climate, infection, respiratory symptoms and sleep to be more difficult to control. Greater perceived controllability of triggers was associated with lower CAT scores, indicating better health status and less impact of the disease on functioning.

CONCLUSION

The CETI is a psychometrically valid measure of perceived exacerbation triggers in patients with COPD. Perceived triggers are associated with clinical outcomes. Assessment of trigger classes and their controllability may prove useful in both research and clinical settings with COPD patients and to further our knowledge in prevention and disease management.

[Methemoglobinemia after inhalation of poppers]

BACKGROUND

This case report presents a case of symptomatic methemoglobinemia (MetHb 31.6%) after inhalation of volatile nitrites (poppers).

METHODS

The patient's medical history and symptoms are discussed together with pathophysiology of methemoglobinemia, diagnostics, and antidote therapy. Pulse oxymetry, arterial blood gas analysis, and CO-oximetry receive particular attention as well as antidote therapy with methylene blue.

RESULTS

The patient was treated successfully with intravenous methylene blue. Within 60 min methemoglobinemia returned to normal values (MetHb 0.6%).

CONCLUSION

Stimulating compounds such as volatile nitrites (poppers) may lead to potentially fatal methemoglobinemia. Swift and accurate diagnosis and targeted therapy with methylene blue can lead to rapid recovery.

Learning to Detect Triggers of Airway Symptoms: The Role of Illness Beliefs, Conceptual Categories and Actual Experience with Allergic Symptoms

Background: In asthma and allergic rhinitis, beliefs about what triggers allergic reactions often do not match objective allergy tests. This may be due to insensitivity for expectancy violations as a result of holding trigger beliefs based on conceptual relationships among triggers. In this laboratory experiment, we aimed to investigate how pre-existing beliefs and conceptual relationships among triggers interact with actual experience when learning differential symptom expectations.

Methods: Healthy participants (N = 48) received information that allergic reactions were a result of specific sensitivities versus general allergic vulnerability. Next, they performed a trigger learning task using a differential conditioning paradigm: brief inhalation of CO₂ enriched air was used to induce symptoms, while participants were led to believe that the symptoms came about as a result of inhaled allergens (conditioned stimuli, CS’s; CS+ followed by symptoms, CS- not followed by symptoms). CS+ and CS- stimuli either shared (e.g., birds-mammals) or did not share (e.g. birds-fungi) category membership. During Acquisition, participants reported symptom expectancy and symptom intensity for all triggers. During a Test 1 day later, participants rated symptom expectancies for old CS+/CS- triggers, for novel triggers within categories, and for exemplars of novel trigger categories. Data were analyzed using multilevel models.

Findings: Only a subgroup of participants (n = 22) showed differences between CO₂ and room air symptoms. In this group of responders, analysis of symptom expectancies during acquisition did not result in significant differential symptom CS+/CS- acquisition. A retention test 1 day later showed differential CS+/CS- symptom expectancies: When CS categories did not share category membership, specific sensitivity beliefs improved retention of CS+/CS- differentiation. However, when CS categories shared category membership, general vulnerability beliefs improved retention of CS+/CS- differentiation. Furthermore, participants showed some selectivity in generalization of symptom expectancies to novel categories, as symptom expectancies did not generalize to novel categories that were unrelated to CS+ or CS- categories. Generalization to novel categories was not affected by information about general vulnerability or specific sensitivities.

Discussion: Pre-existing vulnerability beliefs and conceptual relationships between trigger categories influence differential symptom expectancies to allergic triggers.

Premorbid obesity, but not nutrition, prevents critical illness-induced muscle wasting and weakness

BACKGROUND

The 'obesity paradox' of critical illness refers to better survival with a higher body mass index. We hypothesized that fat mobilized from excess adipose tissue during critical illness provides energy more efficiently than exogenous macronutrients and could prevent lean tissue wasting.

METHODS

In lean and premorbidly obese mice, the effect of 5 days of sepsis-induced critical illness on body weight and composition, muscle wasting, and weakness was assessed, each with fasting and parenteral feeding. Also, in lean and overweight/obese prolonged critically ill patients, markers of muscle wasting and weakness were compared.

RESULTS

In mice, sepsis reduced body weight similarly in the lean and obese, but in the obese with more fat loss and less loss of muscle mass, better preservation of myofibre size and muscle force, and less loss of ectopic lipids, irrespective of administered feeding. These differences between lean and obese septic mice coincided with signs of more effective hepatic fatty acid and glycerol metabolism, and ketogenesis in the obese. Also in humans, better preservation of myofibre size and muscle strength was observed in overweight/obese compared with lean prolonged critically ill patients.

CONCLUSIONS

During critical illness premorbid obesity, but not nutrition, optimized utilization of stored lipids and attenuated muscle wasting and weakness.

Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine: Brussels, Belgium. 15-18 March 2016

[This corrects the article DOI: 10.1186/s13054-016-1208-6.].

Generalization of Respiratory Symptom Triggers

Behavioral management of asthma and other chronic conditions depends upon the accurate identification of environmental factors that trigger symptom onset. In this study, we developed a lab-based conditioning method to study category-based acquisition and generalization of respiratory symptom triggers. During trigger acquisition, unique exemplars of two different categories were shown to a sample of healthy participants (n=48). CS+ exemplars were paired with CO2 inhalation on 50% of trials, while CS- exemplars were always paired with room air. Trigger categories differed in their conceptual similarity. In a generalization task, participants rated symptom expectancy for a set of triggers that included previously seen exemplars, novel exemplars, and exemplars from novel categories. Results show that participants acquired differential symptom expectancies based on category information, which generalized to novel CS+ exemplars and novel categories that shared similarity with the CS+ category. Greater similarity between CS+ and CS- categories increased differential effects for both old and novel exemplars of CS+ and CS- categories, and increased the proportion of novel CS+ exemplars that were remembered as being seen during acquisition. These findings suggest that a more narrowly defined contrast between triggers and nontriggers promotes category-based inference and could help to reduce uncertainty about potential triggers.

Unraveling the relationship between trait negative affectivity and habitual symptom reporting

Objective

In two studies, we aimed at further elucidating the relationship between trait negative affectivity (NA) and habitual symptom reporting (HSR) by relating these variables to measures of executive function, trait questionnaires, and effects of emotion induction.

Methods

Healthy female participants (N = 75) were selected on their scores for trait NA and for the Checklist for Symptoms in Daily Life. Three groups were compared: (1) low NA-low HSR; (2) high NA-low HSR; and (3) high NA-high HSR (low NA-high HSR did not occur). In study 1, participants underwent a Parametric Go/No-go Task and a Stroop Color-Word test, and trait questionnaires measured alexithymia and absorption. Forty-five participants (N = 15 in each group) were further engaged in study 2 to induce state NA using an affective picture paradigm.

Results

Impaired inhibition on the Stroop and Go/No go Task characterized high trait NA, but not high HSR, whereas alexithymia and absorption were elevated in HSR, regardless of trait NA. Negative picture viewing induced elevated state NA in all groups, but only high HSR also reported more bodily symptoms. This effect was moderated, but not mediated by state NA.

Conclusion

High trait NA is a vulnerability factor but not a sufficient condition to develop HSR. Deficient inhibition is related to the broad trait of NA, whereas the moderating effect of state NA on symptom reporting is specific for high HSR. Understanding processes related to alexithymia and absorption may specifically help to explain elevated HSR.

Impact of duration of critical illness on the adrenal glands of human intensive care patients

CONTEXT

Adrenal insufficiency is considered to be prevalent during critical illness, although the pathophysiology, diagnostic criteria, and optimal therapeutic strategy remain controversial. During critical illness, reduced cortisol breakdown contributes substantially to elevated plasma cortisol and low plasma ACTH concentrations.

OBJECTIVE

Because ACTH has a trophic impact on the adrenal cortex, we hypothesized that with a longer duration of critical illness, subnormal ACTH adrenocortical stimulation predisposes to adrenal insufficiency.

DESIGN, SETTING AND PARTICIPANTS

Adrenal glands were harvested 24 hours or sooner after death from 13 long intensive care unit (ICU)-stay patients, 27 short ICU-stay patients, and 13 controls. Prior glucocorticoid treatment was excluded. MAIN OUTCOME AND MEASURE(S): Microscopic adrenocortical zonational structure was evaluated by hematoxylin and eosin staining. The amount of adrenal cholesterol esters was determined by Oil-Red-O staining, and mRNA expression of ACTH-regulated steroidogenic enzymes was quantified.

RESULTS

The adrenocortical zonational structure was disturbed in patients as compared with controls (P < .0001), with indistinguishable adrenocortical zones present only in long ICU-stay patients (P = .003 vs. controls). Adrenal glands from long ICU-stay patients, but not those of short ICU-stay patients, contained 21% less protein (P = .03) and 9% more fluid (P = .01) than those from controls, whereas they tended to weigh less for comparable adrenal surface area. There was 78% less Oil-Red-O staining in long ICU-stay patients than in controls and in short-stay patients (P = .03), the latter similar to controls (P = .31). The mRNA expression of melanocortin 2 receptor, scavenger-receptor class B, member 1, 3-hydroxy-3-methylglutaryl-CoA reductase, steroidogenic acute regulatory protein, and cytochrome P450 cholesterol side-chain cleavage enzyme was at least 58% lower in long ICU-stay patients than in controls (all P ≤ .03) and of melanocortin 2 receptor, scavenger-receptor class B, member 1, steroidogenic acute regulatory protein, and cytochrome P450 cholesterol side-chain cleavage enzyme at least 53% lower than in short ICU-stay patients (all P ≤ .04), whereas gene expression in short ICU-stay patients was similar to controls.

CONCLUSION AND RELEVANCE

Lipid depletion and reduced ACTH-regulated gene expression in prolonged critical illness suggest that sustained lack of ACTH may contribute to the risk of adrenal insufficiency in long-stay ICU patients.

Attentional modulation of reflex cough

OBJECTIVE

Reflex cough is a defensive response generated in the brainstem in response to chemical and mechanical stimulation of the airways. However, converging evidence shows that reflex cough is also influenced by central neural control processes. In this study, we investigate whether reflex cough can be modulated by attentional focus on either external stimuli or internal cough-related stimuli.

METHODS

Healthy volunteers (N = 24; seven men; age range, 18-25 years) completed four blocks of citric acid-induced cough challenges while, simultaneously, auditory stimuli were presented. Within each block, four concentrations were administered (30, 100, 300 and 1,000 mM, randomized). During two subsequent blocks, participants focused their attention externally (counting tones). During the other two blocks, participants focused their attention internally (counting coughs). The order of attentional focus was counterbalanced across participants. Ratings of the urge to cough were collected after each challenge. Cough frequency was determined by audio recording.

RESULTS

Cough frequency was higher when participants focused their attention internally vs externally (P < .05). Also urge to cough was greater during internal vs external focus (P < .05), but the effect was smaller in later blocks of trials.

CONCLUSIONS

Reflex cough can be modulated by attentional focus. Internally focused attention may be a mechanism involved in excessive (idiopathic) cough, while an external focus may be introduced as part of treatments targeting excessive cough.

A 22-channel receive array with Helmholtz transmit coil for anesthetized macaque MRI at 3 T

The macaque monkey is an important model for cognitive and sensory neuroscience that has been used extensively in behavioral, electrophysiological, molecular and, more recently, neuroimaging studies. However, macaque MRI has unique technical differences relative to human MRI, such as the geometry of highly parallel receive arrays, which must be addressed to optimize imaging performance. A 22-channel receive coil array was constructed specifically for rapid high-resolution anesthetized macaque monkey MRI at 3 T. A local Helmholtz transmit coil was used for excitation. Signal-to-noise ratios (SNRs) and noise amplification for parallel imaging were compared with those of single- and four-channel receive coils routinely used for macaque MRI. The 22-channel coil yielded significant improvements in SNR throughout the brain. Using this coil, the SNR in peripheral brain was 2.4 and 1.7 times greater than that obtained with single- or four-channel coils, respectively. In the central brain, the SNR gain was 1.5 times that of both the single- and four-channel coils. Finally, the performance of the array for functional, anatomical and diffusion-weighted imaging was evaluated. For all three modalities, the use of the 22-channel array allowed for high-resolution and accelerated image acquisition.

Enhanced immunoreceptor tyrosine-based activation motif signaling is related to pathological bone resorption during critical illness

Prolonged critically ill patients present with distinct alterations in calcium and bone metabolism. Circulating bone formation markers are reduced and bone resorption markers are substantially elevated, indicating an uncoupling between osteoclast and osteoblast activity, possibly resulting in pronounced bone loss, impaired traumatic or surgical fracture healing, and osteoporosis. In addition, we have previously shown that increased circulating osteoclast precursors in critically ill patients result in increased osteoclastogenesis in vitro, possibly through FcγRIII signaling. In the current study, we investigated the effects of sustained critical illness on bone metabolism at the tissue level in a standardized rabbit model of prolonged (7 days), burn injury-induced critical illness. This in vivo model showed a reduction in serum ionized calcium and osteocalcin levels, as is seen in humans. Trabecular area, bone mineral content, and -density were decreased in sick rabbits [by 43% (p<0.01), 31% (p<0.01), and 29% (p<0.05), respectively], as was the trabecular gene expression of osteoblast and angiogenesis markers, indicating decreased bone formation and impaired vascularization. There was no change in the expression of osteoclast differentiation markers from the canonical RANK/RANKL/OPG pathway, however, there was an increase in expression of markers from the non-canonical, immunoreceptor tyrosine-based activation motif (ITAM) signaling pathway, FcγRIII, and DAP12 (148% and 59%, respectively; p<0.01). The current study has shown a detrimental effect of prolonged critical illness on trabecular bone integrity, possibly explained by reduced osteoblast differentiation and angiogenesis, coupled with increased osteoclastogenesis signaling that may be mediated via the non-canonical immunoreceptor tyrosine-based activation motif signaling pathway.

Determination of platinum surface contamination in veterinary and human oncology centres using inductively coupled plasma mass spectrometry

The objective of this study was to determine the surface contamination with platinum-containing antineoplastic drugs in veterinary and human oncology centres. Inductively coupled plasma mass spectrometry was used to measure platinum levels in surface samples. In veterinary and human oncology centres, 46.3 and 68.9% of the sampled surfaces demonstrated platinum contamination, respectively. Highest platinum levels were found in the preparation rooms (44.6 pg cm(-2)) in veterinary centres, while maximal levels in human centres were found in oncology patient-only toilets (725 pg cm(-2)). Transference of platinum by workers outside areas where antineoplastic drugs were handled was observed in veterinary and human oncology centres. In conclusion, only low levels of platinum contamination attributable to carboplatin were found in the sampled veterinary oncology centres. However, dispersion of platinum outside areas where antineoplastic drugs were handled was detected in veterinary and human oncology centres. Consequently, not only personnel, but also others may be exposed to platinum.

Perceived triggers of asthma: key to symptom perception and management

Adequate asthma management depends on an accurate identification of asthma triggers. A review of the literature on trigger perception in asthma shows that individuals vary in their perception of asthma triggers and that the correlation between self-reported asthma triggers and allergy tests is only modest. In this article, we provide an overview of psychological mechanisms involved in the process of asthma triggers identification. We identify sources of errors in trigger identification and targets for behavioural interventions that aim to improve the accuracy of asthma trigger identification and thereby enhance asthma control.

Charisma: an integrated approach to automatic H&E-stained skeletal muscle cell segmentation using supervised learning and novel robust clump splitting

Histological image analysis plays a key role in understanding the effects of disease and treatment responses at the cellular level. However, evaluating histology images by hand is time-consuming and subjective. While semi-automatic and automatic approaches for image segmentation give acceptable results in some branches of histological image analysis, until now this has not been the case when applied to skeletal muscle histology images. We introduce Charisma, a new top-down cell segmentation framework for histology images which combines image processing techniques, a supervised trained classifier and a novel robust clump splitting algorithm. We evaluate our framework on real-world data from intensive care unit patients. Considering both segmentation and cell property distributions, the results obtained by our method correspond well to the ground truth, outperforming other examined methods.

Inductively coupled plasma mass-spectrometric determination of platinum in excretion products of client-owned pet dogs

Residues of antineoplastic drugs in canine excretion products may represent exposure risks to veterinary personnel, owners of pet dogs and other animal care-takers. The aim of this study was to measure the extent and duration of platinum (Pt) excretion in pet dogs treated with carboplatin. Samples were collected before and up to 21 days after administration of carboplatin. We used validated, ultra-sensitive, inductively coupled plasma-mass spectrometry assays to measure Pt in canine urine, faeces, saliva, sebum and cerumen. Results showed that urine is the major route of elimination of Pt in dogs. In addition, excretion occurs via faeces and saliva, with the highest amounts eliminated during the first 5 days. The amount of excreted Pt decreased over time but was still quantifiable at 21 days after administration of carboplatin. In conclusion, increased Pt levels were found in all measured excretion products up to 21 days after administration of carboplatin to pet dogs, with urine as the main route of excretion. These findings may be used to further adapt current veterinary guidelines on safe handling of antineoplastic drugs and treated animals.

Surface based analysis of diffusion orientation for identifying architectonic domains in the in vivo human cortex

Diffusion tensor MRI is sensitive to the coherent structure of brain tissue and is commonly used to study large-scale white matter structure. Diffusion in gray matter is more isotropic, however, several groups have observed coherent patterns of diffusion anisotropy within the cerebral cortical gray matter. We extend the study of cortical diffusion anisotropy by relating it to the local coordinate system of the folded cerebral cortex. We use 1mm and sub-millimeter isotropic resolution diffusion imaging to perform a laminar analysis of the principal diffusion orientation, fractional anisotropy, mean diffusivity and partial volume effects. Data from 6 in vivo human subjects, a fixed human brain specimen and an anesthetized macaque were examined. Large regions of cortex show a radial diffusion orientation. In vivo human and macaque data displayed a sharp transition from radial to tangential diffusion orientation at the border between primary motor and somatosensory cortex, and some evidence of tangential diffusion in secondary somatosensory cortex and primary auditory cortex. Ex vivo diffusion imaging in a human tissue sample showed some tangential diffusion orientation in S1 but mostly radial diffusion orientations in both M1 and S1.

An implanted 8-channel array coil for high-resolution macaque MRI at 3T

An 8-channel receive coil array was constructed and implanted adjacent to the skull in a male rhesus monkey in order to improve the sensitivity of (functional) brain imaging. The permanent implant was part of an acrylic headpost assembly and only the coil element loop wires were implanted. The tuning, matching, and preamplifier circuitry was connected via a removable external assembly. Signal-to-noise ratio (SNR) and noise amplification for parallel imaging were compared to single-, 4-, and 8-channel external receive-only coils routinely used for macaque fMRI. In vivo measurements showed significantly improved SNR within the brain for the implanted versus the external coils. Within a region-of-interest covering the cerebral cortex, we observed a 5.4-, 3.6-fold, and 3.4-fold increase in SNR compared to the external single-, 4-, and 8-channel coils, respectively. In the center of the brain, the implanted array maintained a 2.4×, 2.5×, and 2.1× higher SNR, respectively compared to the external coils. The array performance was evaluated for anatomical, diffusion tensor and functional brain imaging. This study suggests that a stable implanted phased-array coil can be used in macaque MRI to substantially increase the spatial resolution for anatomical, diffusion tensor, and functional imaging.

Predicting asthma treatment outcome at diagnosis: the role of symptom perception during a histamine challenge test

OBJECTIVE

In asthma, many treatment decisions are dependent upon patient perception/patient report of asthma symptoms. Discrepancies between patient perception of asthma symptoms and objective indicators of pathophysiology are widespread and can hinder asthma treatment. Early detection of problems in asthma symptom perception may be a first step to help these patients. We investigated the predictive value of symptom perception during a histamine challenge test (HCT) at asthma diagnosis for patient-rated outcome of asthma treatment 3 months later.

METHODS

In a prospective observational study, persons with asthma (N = 60) showing bronchial hyperresponsiveness in a HCT completed questions on asthma symptoms and negative affectivity (NA). The HCT was extended with an ambiguous situation suggesting asthma symptoms despite physiological recovery. Lung function (forced expiratory volume in 1 second (FEV(1))) and symptom ratings were measured during the test (after each histamine dosage), and we constructed several measures of asthma symptom perception based on FEV(1) and symptom ratings. Three months later, 30 participants completed questionnaires on asthma control and asthma-related quality of life.

RESULTS

Symptoms reported during HCT predicted worse asthma control and quality of life 3 months later. The prospective association between symptoms during HCT and asthma control remained significant when controlling for NA and baseline lung function. These effects were strongest for symptoms during ambiguous situations.

CONCLUSIONS

Higher symptom levels at the start of the HCT and during recovery may reflect a tendency to inaccurately perceive asthma symptoms in ambiguous situations. Assessing symptoms during diagnostic challenge tests can help predict problems with asthma treatment.

Symptoms, lung function, and perception of asthma control: an exploration into the heterogeneity of the asthma control construct

BACKGROUND

Asthma control is still surprisingly poor, which may be related to factors causing discrepancies between objective lung function measures and subjective symptom reports or discrepancies between objective indicators of asthma control and control perception. Identifying patients prone to such discrepancies may help to understand asthma control problems.

METHODS

Ninety-four persons with asthma participated in this study. We used cluster analysis to identify different subgroups of asthma control, based on a measure of lung function and self-report of daytime and nighttime symptoms, activity limitations, reliever medication use, and perception of asthma control. Subsequently, we explored between-cluster differences in clinical and psychological characteristics.

RESULTS

We identified two homogeneous clusters: a cluster of persons with poorly controlled asthma and a cluster of persons with well-controlled asthma. A third cluster included persons with an intermediate level of asthma control, an absence of nighttime symptoms, and a reduced impact of asthma symptoms on daily activities despite high levels of symptoms and reliever medication use. Members of the poorly controlled asthma cluster showed higher symptom levels, more catastrophic thinking, and activity avoidance beliefs compared with members of other clusters.

CONCLUSION

The clusters we identified crosscut current definitions of asthma severity and asthma control and indicate the importance of affective evaluation of symptoms in explaining poor asthma control.

The influence of fear of symptoms and perceived control on asthma symptom perception

OBJECTIVE

Self-reported asthma symptoms correlate only modestly with measures of underlying pathophysiological mechanisms. In this study, we investigated the role of fear of symptoms and perceived control on respiratory symptom perception in patients with asthma.

METHODS

Patients with intermittent to moderate persistent asthma (N=32) were administered 4 subsequent rebreathing challenges (one using 100% O(2) and three using 5% CO(2) and 95% O(2)). We manipulated perceived control by providing information on the availability/unavailability of rescue medication during the challenges (perceived control/no control condition). Perceived symptoms and lung function were assessed after each rebreathing challenge.

RESULTS

Persons with low fear of symptoms reported respiratory symptoms to be less unpleasant during the perceived control condition compared to the no control condition. The reverse was found for persons with high fear of symptoms. The interaction between fear of symptoms and the control manipulations was mediated by threat perception.

CONCLUSION

Messages intended to increase perceived control over symptoms may actually increase threat in persons with high fear of symptoms and eventually increase unpleasantness of respiratory sensations. This finding underlines the importance of affective processes in the perception of asthma symptoms and shows that instructions to patients should take pre-existing fear levels into account.

Dyspnea-related anxiety: The Dutch version of the Breathlessness Beliefs Questionnaire

Dyspnea-related anxiety may lead to reduced quality of life and functional disability through fearful avoidance of dyspnea-evoking activity. We describe the validation of a generic - diagnosis-independent - instrument assessing dyspnea-related anxiety. A total of 187 patients with respiratory diseases completed the Breathlessness Beliefs Questionnaire (BBQ), a 17-item questionnaire adapted from the Tampa Scale for Kinesiophobia (TSK), a measure of how harmful pain patients think painful movement is and to what extent they think activity should be avoided. Measures of negative and positive affectivity (PANAS), anxiety and depression (HADS), functional status (PFSDQ), and health-related quality of life (CRDQ) were also completed. Principal component analysis and item-total correlations suggested a reliable (reduced) 11-item BBQ (Cronbach's alpha = .85) with two factors converging with the TSK factors: a 'somatic focus' factor assessing the harmfulness of dyspnea and the underlying pathology and an 'activity avoidance' factor assessing beliefs that activity should be avoided. Correlational analyses support the construct validity of the BBQ: higher scores on the BBQ are associated with reduced health-related quality of life and functional status. Associations between 'somatic focus' and negative affectivity and anxiety and between 'activity avoidance' and positive affectivity and depression further supported the validity of the BBQ and its subscales. The BBQ is a valid, short, and useful instrument to assess respiratory patients' beliefs about the harmfulness of their disease and physical activities. Further research is needed to document to what extent BBQ scores are related to daily life activities and symptoms.

Inaccurate perception of asthma symptoms: a cognitive-affective framework and implications for asthma treatment

Inaccurate perception of respiratory symptoms is often found in asthma patients. Typically, patients who inaccurately perceive asthma symptoms are divided into underperceivers and overperceivers. In this paper we point out that this division is problematic. We argue that little evidence exists for a trait-like stability of under- and overperception and that accuracy of respiratory symptom perception is highly variable within persons and strongly influenced by contextual information. Particularly, expectancy and affective cues appear to have a powerful influence on symptom accuracy. Based on these findings and incorporating recent work on associative learning, attention and mental representations in anxiety and symptom perception, we propose a cognitive-affective model of symptom perception in asthma. The model can act as a framework to understand both normal perception as well as under- and overperception of asthma symptoms and can guide the development of affect-related interventions to improve perceptual accuracy, asthma control and quality of life in asthma patients.

Ligation of the superficial femoral vein in prevention of pulmonary embolism: an old fashion procedure?

From 1974 to 1988, interruption of the superficial femoral vein (SFV) was performed to prevent pulmonary embolism (PE) in 73 patients. The mean age of the patients was 62 years. Phlebography showed thrombi in the following localizations: calf veins (67.3%), superficial femoral or popliteal veins (56.6%), common femoral veins (19.5%) and iliac veins (2.7%). A floating thrombus in the popliteal or femoral vein was the main indication for surgery in 97.3% of patients. Pulmonary embolism had occurred in 76.7% and was associated with neoplasm in 13.7%. Ligation of the SFV was performed in 93 limbs and completed iliac or femoral thrombectomy in 32.3%. The procedure was performed under locoregional anesthesia in 82.9% of the cases. Hospital mortality was 1.4% and 3 year survival, considering only PE related deaths was 95.3 +/- 2.7%. Follow-up was complete for all patients and averaged 3.0 years, for a 3 years PE-free rate of 90.8 +/- 3.6%. Persistent symptoms included increased limb tenseness in 12.5% and mild ankle edema in 25%. Bilateral strain-gauge plethysmography (SGP) was obtained in 65 limbs. The time necessary to obtain a 50, 75 and 100% decrease in calf volume (respectively T1/2, T3/4 and TT) was calculated for the operated limb and compared with the untreated limbs used as controls. A prolongation of T1/2 from 2.5 +/- 0.3 sec in controls to 4.3 +/- 0.4 sec in the operated limb (p less than 0.01) was found. Thus, our experience with ligation of the superficial femoral vein is favourable since long-term ill effects have been minimal and strain gauge plethysmography (SGP) showed only mildly altered venous drainage.(ABSTRACT TRUNCATED AT 250 WORDS)