Activation of epithelial and inflammatory pathways in adolescent elite athletes exposed to intense exercise and air pollution

RATIONALE

Participation in high-intensity exercise in early life might act as stressor to the airway barrier.

OBJECTIVES

To investigate the effect of intense exercise and associated exposure to air pollution on the airway barrier in adolescent elite athletes compared with healthy controls and to study exercise-induced bronchoconstriction (EIB) in this population.

METHODS

Early-career elite athletes attending 'Flemish-Elite-Sports-Schools' (12-18 years) of 4 different sport disciplines (n=90) and control subjects (n=25) were recruited. Presence of EIB was tested by the eucapnic voluntary hyperventilation (EVH) test. Markers at mRNA and protein level; RNA-sequencing; carbon load in airway macrophages were studied on induced sputum samples.

RESULTS

444 genes were differentially expressed in sputum from athletes compared with controls, which were related to inflammation and epithelial cell damage and sputum samples of athletes contained significantly more carbon loaded airway macrophages compared with controls (24%, 95% CI 20% to 36%, p<0.0004). Athletes had significantly higher substance P (13.3 pg/mL, 95% CI 2.0 to 19.2) and calprotectin (1237 ng/mL, 95% CI 531 to 2490) levels as well as IL-6, IL-8 and TNF-α mRNA levels compared with controls (p<0.05). The incidence of EIB in athletes was 9%. The maximal fall in forced expiratory volume in 1 s (%) after EVH test in athletes was significantly associated with prior PM10 and PM2.5 exposure.

CONCLUSION

Early-career elite athletes showed increased markers of air pollution exposure, epithelial damage and airway inflammation compared with controls. Acute exposure to increased air pollution PM10 levels was linked to increased airway hyper-reactivity.

TRIAL REGISTRATION NUMBER

NCT03587675.

Public health impact and return on investment of Belgium's pediatric immunization program

Objective

We evaluated the public health impact and return on investment of Belgium's pediatric immunization program (PIP) from both healthcare-sector and societal perspectives.

Methods

We developed a decision analytic model for 6 vaccines routinely administered in Belgium for children aged 0-10 years: DTaP-IPV-HepB-Hib, DTaP-IPV, MMR, PCV, rotavirus, and meningococcal type C. We used separate decision trees to model each of the 11 vaccine-preventable pathogens: diphtheria, tetanus, pertussis, poliomyelitis, Haemophilus influenzae type b, measles, mumps, rubella, Streptococcus pneumoniae, rotavirus, and meningococcal type C; hepatitis B was excluded because of surveillance limitations. The 2018 birth cohort was followed over its lifetime. The model projected and compared health outcomes and costs with and without immunization (based on vaccine-era and pre-vaccine era disease incidence estimates, respectively), assuming that observed reductions in disease incidence were fully attributable to vaccination. For the societal perspective, the model included productivity loss costs associated with immunization and disease in addition to direct medical costs. The model estimated discounted cases averted, disease-related deaths averted, life-years gained, quality-adjusted life-years gained, costs (2020 euros), and an overall benefit-cost ratio. Scenario analyses considered alternate assumptions for key model inputs.

Results

Across all 11 pathogens, we estimated that the PIP prevented 226,000 cases of infections and 200 deaths, as well as the loss of 7,000 life-years and 8,000 quality-adjusted life-years over the lifetime of a birth cohort of 118,000 children. The PIP was associated with discounted vaccination costs of €91 million from the healthcare-sector perspective and €122 million from the societal perspective. However, vaccination costs were more than fully offset by disease-related costs averted, with the latter amounting to a discounted €126 million and €390 million from the healthcare-sector and societal perspectives, respectively. As a result, pediatric immunization was associated with overall discounted savings of €35 million and €268 million from the healthcare-sector and societal perspectives, respectively; every €1 invested in childhood immunization resulted in approximately €1.4 in disease-related cost savings to the health system and €3.2 in cost savings from a societal perspective for Belgium's PIP. Estimates of the value of the PIP were most sensitive to changes in input assumptions for disease incidence, productivity losses due to disease-related mortality, and direct medical disease costs.

Conclusion

Belgium's PIP, which previously had not been systematically assessed, provides large-scale prevention of disease-related morbidity and premature mortality, and is associated with net savings to health system and society. Continued investment in the PIP is warranted to sustain its positive public health and financial impact.

A molecular understanding of citrate adsorption on calcium oxalate polyhydrates

Calcium oxalate precipitation is a common pathological calcification in the human body, whereby crystallite morphology is influenced by the chelating properties of biological ions such as citrate. It has been suggested that citrate could steer oxalate formation towards its dihydrated form and away from the monohydrated form, which was identified as a major cause for disease. To assess the influence of the citrate ion on the resulting calcium oxalate, surface energies were calculated at the dispersion-corrected density functional level of theory for both monohydrated and dihydrated calcium oxalate. Different adsorption geometries were considered by varying the attacking angle of citrate as well as by considering the citrate ion on top of an adsorbed water layer or penetrating the water layer. The obtained results were compared to ab initio molecular dynamics simulations and experimental scanning electron microscope images. A strong preference for citrate adsorption on calcium oxalate dihydrate was observed, suggesting medical applications for the treatment of such pathological calcifications.

The burden and surveillance of RSV disease in young children in Belgium-expert opinion

Infections with respiratory syncytial virus (RSV) can cause severe disease. In young children, RSV is the most common cause of lower respiratory tract illness and life-threatening infections most commonly occur in the first years of life. In adults, elderly and immunocompromised people are most vulnerable. Recently there has been an acceleration in the development of candidate RSV vaccines, monoclonal antibodies and therapeutics which are expected to become available in Europe within the next 2-10 years. Understanding the true burden of childhood RSV disease will become very important to support public health authorities and policy makers in the assessment of new therapeutic opportunities against RSV disease. A systematic literature search was performed to map local data on the burden of RSV disease and to evaluate available RSV surveillance systems. A group of 9 paediatric infectious diseases specialists participated in an expert panel. The purpose of this meeting was to evaluate and map the burden associated with RSV infection in children, including patient pathways and the epidemiological patterns of virus circulation in Belgium. Sources of information on the burden of RSV disease in Belgium are very limited. For the outpatient setting, it is estimated that 5-10% of young patients seen in primary care are referred to the hospital. Around 3500 children between 0 and 12 months of age are hospitalized for RSV-bronchiolitis every year and represent the majority of all hospitalizations. The current Belgian RSV surveillance system was evaluated and found to be insufficient. Knowledge gaps are highlighted and future perspectives and priorities offered.

CONCLUSION

The Belgian population-based RSV surveillance should be improved, and a hospital-led reporting system should be put in place to enable the evaluation of the true burden of RSV disease in Belgium and to improve disease management in the future.

WHAT IS KNOWN

• RSV bronchiolitis is a very important cause of infant hospitalization. • The burden of disease in the community is poorly studied and underestimated.

WHAT IS NEW

• This expert opinion summarizes knowledge gaps and offers insights that allow improvement of local surveillance systems in order to establish a future-proof RSV surveillance system.

Blood transcriptomics to facilitate diagnosis and stratification in pediatric rheumatic diseases - a proof of concept study

BACKGROUND

Transcriptome profiling of blood cells is an efficient tool to study the gene expression signatures of rheumatic diseases. This study aims to improve the early diagnosis of pediatric rheumatic diseases by investigating patients' blood gene expression and applying machine learning on the transcriptome data to develop predictive models.

METHODS

RNA sequencing was performed on whole blood collected from children with rheumatic diseases. Random Forest classification models were developed based on the transcriptome data of 48 rheumatic patients, 46 children with viral infection, and 35 controls to classify different disease groups. The performance of these classifiers was evaluated by leave-one-out cross-validation. Analyses of differentially expressed genes (DEG), gene ontology (GO), and interferon-stimulated gene (ISG) score were also conducted.

RESULTS

Our first classifier could differentiate pediatric rheumatic patients from controls and infection cases with high area-under-the-curve (AUC) values (AUC = 0.8 ± 0.1 and 0.7 ± 0.1, respectively). Three other classifiers could distinguish chronic recurrent multifocal osteomyelitis (CRMO), juvenile idiopathic arthritis (JIA), and interferonopathies (IFN) from control and infection cases with AUC ≥ 0.8. DEG and GO analyses reveal that the pathophysiology of CRMO, IFN, and JIA involves innate immune responses including myeloid leukocyte and granulocyte activation, neutrophil activation and degranulation. IFN is specifically mediated by antibacterial and antifungal defense responses, CRMO by cellular response to cytokine, and JIA by cellular response to chemical stimulus. IFN patients particularly had the highest mean ISG score among all disease groups.

CONCLUSION

Our data show that blood transcriptomics combined with machine learning is a promising diagnostic tool for pediatric rheumatic diseases and may assist physicians in making data-driven and patient-specific decisions in clinical practice.

Guided Gradual Egg-Tolerance Induction in Hen's Egg Allergic Children Tolerating Baked Egg: A Prospective Randomized Trial

Background

Over the last few years, studies have shown that the majority of egg allergic children tolerate baked egg (e.g., cake), and that consuming baked egg accelerates the resolution of egg allergy. However, few prospective studies demonstrate the step-wise reintroduction of egg at home after developing baked egg tolerance. Although this could have a positive impact on the children's quality of life and nutrition. Additionally, research supporting the theoretical concept that heating in the presence or absence of wheat causes reduced allergenicity of egg proteins is limited.

Objective

To investigate the clinically most favorable duration of gradual egg-tolerance induction in baked egg tolerant children at home, with regard to complete raw egg tolerance.

Methods

Baked egg tolerant children above 12 months of age were randomly assigned to a short- or long arm protocol. In the short arm, egg-tolerance induction was studied over 18 months compared to 30 months in the long arm. Children were guided through this protocol involving the step-wise introduction of increasingly allergenic forms of egg starting with baked egg offered as cake, followed by hard-boiled egg, omelet/waffle/pancake, soft-boiled egg, and finally raw egg. We hereby designed this protocol based on the influence of thermal processing in the presence or absence of wheat on egg proteins, as investigated by ELISA, SDS-PAGE, and immunoblotting. At inclusion, children either passed an in-hospital cake challenge or had ovomucoid sIgE ≤1.2 kUA/L, which was considered safe for introduction at home.

Results

Gel electrophoresis revealed that the ovalbumin band became weaker with heating, while the ovomucoid band remained stable. In accordance, the IgE-binding to ovalbumin decreased with extensive heating, as opposed to ovomucoid. However, heating in the presence of wheat led to a decreased IgE reactivity to ovomucoid. Of the 78 children in the intention-to-treat group, 39 were randomized to each arm. Fifty-eight children reached the raw egg tolerance endpoint, of which 80% were in the short arm and 69% in the long arm. Within the short arm, the median time to raw egg tolerance was 24 months (95% CI, 21–27 months) compared to 30 months (95% CI, 28–32 months) in the long arm (p = 0.005). No grade IV reactions or cases of eosinophilic esophagitis were observed. The short arm was considered to be non-inferior to the long arm.

Conclusion

Our gradual short arm protocol appears to be safe and allows clinicians to guide baked egg tolerant children toward raw egg tolerance at home. The allergenicity of the egg proteins was affected by heating temperature and duration, as well as the presence of wheat.

Explaining the formation of a plateau in rotavirus vaccine impact on rotavirus hospitalisations in Belgium

BACKGROUND

Observational data on the reduction in hospitalisations after rotavirus vaccine introduction in Belgium suggest that vaccine impact plateaued at an unexpectedly high residual hospitalisation rate. The objective of this analysis was to identify factors that influence real-world vaccine impact.

METHODS

Data were collected on hospitalisations in children aged ≤ 5 years with rotavirus disease from 11 hospitals since 2005 (the RotaBIS study). The universal rotavirus vaccination campaign started late in 2006. A mathematical model simulated rotavirus hospitalisations in different age groups using vaccine efficacy and herd effect, influenced by vaccine coverage, vaccine waning, and secondary infection sources. The model used optimisation analysis to fit the simulated curve to the observed data, applying Solver add-in software. It also simulated an 'ideal' vaccine introduction maximising hospitalisation reduction (maximum coverage, maximum herd effect, no waning), and compared this with the best-fit simulated curve. Modifying model input values identified factors with the largest impact on hospitalisations.

RESULTS

Compared with the 'ideal' simulation, observed data showed a slower decline in hospitalisations and levelled off after three years at a higher residual hospitalisation rate. The slower initial decline was explained by the herd effect in unvaccinated children. The higher residual hospitalisation rate was explained by starting the vaccine programme in November, near the rotavirus seasonal peak. This resulted in low accumulated vaccine coverage during the first rotavirus disease peak season, with the consequential appearance of secondary infection sources. This in turn reduced the herd effect, resulting in a diminished net impact.

CONCLUSIONS

Our results indicate that countries wishing to maximise the impact of rotavirus vaccination should start vaccinating well ahead of the rotavirus seasonal disease peak. This maximises herd effect during the first year leading to rapid and high reduction in hospitalisations. Secondary infection sources explain the observed data in Belgium better than vaccine waning.

Belgian Consensus Recommendations to Prevent Vitamin K Deficiency Bleeding in the Term and Preterm Infant

Neonatal vitamin K prophylaxis is essential to prevent vitamin K deficiency bleeding (VKDB) with a clear benefit compared to placebo. Various routes (intramuscular (IM), oral, intravenous (IV)) and dosing regimens were explored. A literature review was conducted to compare vitamin K regimens on VKDB incidence. Simultaneously, information on practices was collected from Belgian pediatric and neonatal departments. Based on the review and these practices, a consensus was developed and voted on by all co-authors and heads of pediatric departments. Today, practices vary. In line with literature, the advised prophylactic regimen is 1 or 2 mg IM vitamin K once at birth. In the case of parental refusal, healthcare providers should inform parents of the slightly inferior alternative (2 mg oral vitamin K at birth, followed by 1 or 2 mg oral weekly for 3 months when breastfed). We recommend 1 mg IM in preterm <32 weeks, and the same alternative in the case of parental refusal. When IM is perceived impossible in preterm <32 weeks, 0.5 mg IV once is recommended, with a single additional IM 1 mg dose when IV lipids are discontinued. This recommendation is a step towards harmonizing vitamin K prophylaxis in all newborns.

Thymus satureioides and Origanum majorana essential oils improve the quality of Beni Arouss buck semen during storage at 4°C

This study aims to investigate the effects of essential oils (EOs), extracted from Thymus satureioides (TS) and Origanum majorana (OM), on Beni Arouss buck semen quality stored in skimmed milk at 4°C. EOs were extracted by hydro-distillation, and the chemical compounds were determined. Ejaculates were collected from six Beni Arouss bucks, once a week for 10 weeks, and they were pooled, divided into five equal aliquots and diluted to 400 × 10⁶ sperm/ml with skimmed milk supplemented with 0.01% of OM EO, 0.01% of TS EO, 0.05% of OM EO and 0.05% of TS EO. Non-supplemented skimmed milk was considered as a control. Semen motility, kinematic parameters, viability, abnormality, membrane integrity and lipid peroxidation were evaluated at 0, 4, 8, 24, 28, 32 and 48 hr of liquid storage at 4°C. The main EO components were carvacrol (31.7%), thymol (28.0%) and borneol (14.4%) for TS, and terpinene-4-ol (31.2%), γ-terpinene (17.4%) and α-terpinene (12.7%) for OM. The results highlighted a dose-dependent effect of TS and OM EOs on all semen quality parameters. 0.01% of both EOs had a beneficial effect on the sperm preservation stored at 4°C compared with control (p < .05) excepted for the straight-line velocity. The 0.05% EO addition had harmful effects during storage particularly for TS EO. In conclusion, 0.01% of TS and OM EOs are recommended to improve the Beni Arouss buck semen preservation at 4°C.

Real-time versus thermal desorption selected ion flow tube mass spectrometry for quantification of breath volatiles

RATIONALE

Selected ion flow tube mass spectrometry (SIFT-MS) is versatile, rapidly provides result output and determines a wide range of volatiles, making it suitable for biomedical applications. When direct sampling into the SIFT-MS instrument is impractical, combining thermal desorption (TD) and SIFT-MS might offer a solution as it allows sample storage on sorbent tubes for later analysis. This work compares off-line TD SIFT-MS and real-time SIFT-MS for the quantification of selected breath volatiles.

METHODS

Ten healthy non-smoking individuals provided 60 breath samples per method. For off-line analysis, breath was collected onto sorbent tubes via a breath sampler provided with filtered inspiratory air. After TD, samples were re-collected in Tedlar bags which were then connected to the SIFT-MS instrument. For real-time analysis, breath was sampled directly into the instrument. In both cases the analytical method included a total of 155 product ions, and 14 selected volatiles were quantified. The agreement between the methods was assessed using Pearson correlation coefficients and Bland-Altman plots.

RESULTS

Overall, correlations between real-time and off-line analysis were moderate to very strong (r = 0.43-0.92) depending on the volatile of interest, except for 2,3-butanedione and styrene. The difference between real-time and off-line measured breath concentrations (average bias) ranged between -14.57 and 20.48 ppbv. For acetone and isoprene, it was 251.53 and 31.9 ppbv, respectively.

CONCLUSIONS

Real-time SIFT-MS and off-line TD SIFT-MS for quantification of selected breath volatiles did not show optimal agreement. Analyzing a multitude of analytes in breath via direct exhalation into a SIFT-MS instrument for real-time analysis is challenging. On the other hand, off-line analysis using a breath collection device also has its issues such as possible sample losses due to selective absorption depending on the sorbent used or during desorption and transfer to the instrument. Despite these drawbacks, both methods were moderately well correlated.

The Type and Concentration of Inoculum and Substrate as Well as the Presence of Oxygen Impact the Water Kefir Fermentation Process

Eleven series of water kefir fermentation processes differing in the presence of oxygen and the type and concentration of inoculum and substrate, were followed as a function of time to quantify the impact of these parameters on the kinetics of this process via a modeling approach. Increasing concentrations of the water kefir grain inoculum increased the water kefir fermentation rate, so that the metabolic activity during water kefir fermentation was mainly associated with the grains. Water kefir liquor could also be used as an alternative means of inoculation, but the resulting fermentation process progressed slower than the one inoculated with water kefir grains, and the production of water kefir grain mass was absent. Substitution of sucrose with glucose and/or fructose reduced the water kefir grain growth, whereby glucose was fermented faster than fructose. Lacticaseibacillus paracasei (formerly known as Lactobacillus paracasei), Lentilactobacillus hilgardii (formerly known as Lactobacillus hilgardii), Liquorilactobacillus nagelii (formerly known as Lactobacillus nagelii), Saccharomyces cerevisiae, and Dekkera bruxellensis were the main microorganisms present. Acetic acid bacteria were present in low abundances under anaerobic conditions and only proliferated under aerobic conditions. Visualization of the water kefir grains through scanning electron microscopy revealed that the majority of the microorganisms was attached onto their surface. Lactic acid bacteria and yeasts were predominantly associated with the grains, whereas acetic acid bacteria were predominantly associated with the liquor.

Closing schools for SARS-CoV-2: a pragmatic rapid recommendation

BACKGROUND

In Belgium, schools closed during the first lockdown in March 2020, with a partial reopening in May. They fully reopened in September. During the summer, infections started to increase in the general population, speeding up in September. Some measures were taken to limit social contacts but those were insufficient to mitigate the exponential rise of infections in October. Children were still receiving all lessons at school at that time and it was questioned whether this position was tenable. We systematically compared the benefits and harms of closing primary and secondary schools and developed a recommendation.

METHODS

A multidisciplinary panel, including school pupils and teachers, educational experts, clinicians and researchers, produced this recommendation in compliance with the standards for trustworthy rapid guidelines. The recommendation is based on data collected through national surveillance or studies from Belgium, and supported by a rapid literature review.

RESULTS

Closing schools during the first lockdown probably resulted in a large learning delay and possibly led to more cases of child abuse. We are uncertain about the effect on the infection rate, hospitalisations, transmission rates, mental health of children, teachers and parents. The panel concluded that the balance of benefits and harms of closing schools clearly shifts against closing schools. Detrimental effects are even worse for vulnerable children. This recommendation is affected by the local virus circulation.

CONCLUSION

The guideline panel issues a strong recommendation against closing schools when the virus circulation is low to moderate, and a weak recommendation against closing schools when the virus circulation is high. It does not apply when the school system cannot function due to lack of teachers, too many children who are at home or a shortage of support services. As the results of international studies are consistent with Belgian study results, this recommendation may also be relevant internationally.

Diagnostic characterization of respiratory allergies by means of a multiplex immunoassay

Allergic sensitization is commonly assessed in patients by performing the skin prick test (SPT) or determining specific immunoglobulin (IgE) levels in blood samples with the ImmunoCAP™ assay, which measures each allergen and sample separately. This paper explores the possibility to investigate respiratory allergies with a high throughput method, the Meso Scale Discovery (MSD) multiplex immunoassay, measuring IgE levels in low volumes of blood. The MSD multiplex immunoassay, developed and optimized with standards and allergens from Radim Diagnostics, was validated against the SPT and the ImmunoCAP assay. For 18 adults (15 respiratory allergy patients and three controls), blood collection and the SPT were performed within the same hour. Pearson correlations and Bland-Altman analysis showed high comparability of the MSD multiplex immunoassay with the SPT and the ImmunoCAP assay, except for house dust mite. The sensitivity of the MSD multiplexed assay was ≥78% for most allergens compared to the SPT and ImmunoCAP assay. Additionally, the specificity of the MSD multiplex immunoassay was ≥ 87% - the majority showing 100% specificity. Only the rye allergen had a low specificity when compared to the SPT, probably due to cross-reactivity. The reproducibility of the MSD multiplex immunoassay, assessed as intra- and interassay reproducibility and biological variability between different sampling moments, showed significantly high correlations (r = 0·943-1) for all tested subjects (apart from subject 13; r = 0·65-0·99). The MSD multiplex immunoassay is a reliable method to detect specific IgE levels against respiratory allergens in a multiplexed and high-throughput manner, using blood samples as small as from a finger prick.

Lessons Learned from Long-Term Assessment of Rotavirus Vaccination in a High-Income Country: The Case of the Rotavirus Vaccine Belgium Impact Study (RotaBIS)

INTRODUCTION

The rotavirus (RV) vaccine Belgium Impact Study (RotaBIS) evaluated the vaccine effect on RV-related hospital care in children up to 5 years old over a period of 13 years. Different forces were identified that influence the reduction in hospital care. Our analysis aims to report on the current RotaBIS dataset and explore through model simulation whether, how, and when the results could have been improved.

METHODS

As performed in previous assessments, this analysis evaluated RV-related events per year, per age group, RV nosocomial infections, hospitalization duration, and herd effect. It subsequently identified results that were surprising or unexpected. To know whether those data could have been improved through specific interventions, we developed a model with the forces acting on the disease transmission and the vaccine effect on RV-related hospital care. Scenario analysis of the forces should explain the current findings and identify ways to optimize the results.

RESULTS

The RotaBIS data show that annual RV-related hospital cases (n = 1345 pre-vaccination) dropped by 70% (95% confidence interval [CI] 66-74%) by year 5 (n = 395) after vaccine introduction, and by 84% (95% CI 79-89%) by year 10 (n = 217). The herd effect during the first year was limited to 14% extra gain. During the last 5 years, small disease increases were seen biennially. The simulation model indicates that higher vaccine coverage of the major transmitters during the peak season of the first year of vaccination could have reduced RV-related hospital care by nearly 90% at 5 and 10 years after vaccine introduction owing to a higher herd effect. The smaller peaks observed in recent years would have been dramatically reduced.

CONCLUSION

The current RotaBIS data show a maintained reduction, around 76%, in RV hospitalization cases. Simulations show that these results could have been improved to an important extent with a more optimal initiation of the vaccination program.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT01563146 and NCT01563159.

Real-time selected ion flow tube mass spectrometry to assess short- and long-term variability in oral and nasal breath

Breath-based non-invasive diagnostics have the potential to provide valuable information about a person's health status. However, they are not yet widely used in clinical practice due to multiple factors causing variability and the lack of standardized procedures. This study focuses on the comparison of oral and nasal breathing, and on the variability of volatile metabolites over the short and long term. Selected ion flow tube mass spectrometry (SIFT-MS) was used for online analysis of selected volatile metabolites in oral and nasal breath of 10 healthy individuals five times in one day (short-term) and six times spread over three weeks (long-term), resulting in nearly 100 breath samplings. Intra-class correlation coefficients (ICCs) were used to assess short- and long-term biological variability. Additionally, the composition of ambient air was analyzed at different samplings. The selected volatiles common in exhaled breath were propanol, 2,3-butanedione, acetaldehyde, acetone, ammonia, dimethyl sulfide, isoprene, pentane, and propanal. Additionally, environmental compounds benzene and styrene were analyzed as well. Volatile metabolite concentrations in ambient air were not correlated with those in exhaled breath and were significantly lower than in breath samples. All volatiles showed significant correlation between oral and nasal breath. Five were significantly higher in oral breath compared to nasal breath, while for acetone, propanal, dimethyl sulfide, and ammonia, concentrations were similar in both matrices. Variability depended on the volatile metabolite. Most physiologically relevant volatiles (acetone, isoprene, propanol, acetaldehyde) showed good to very good biological reproducibility (ICC > 0.61) mainly in oral breath and over a short-term period of one day. Both breathing routes showed relatively similar patterns; however, bigger differences were expected. Therefore, since sampling from the mouth is practically more easy, the latter might be preferred.

Diagnosing enterovirus meningitis via blood transcriptomics: an alternative for lumbar puncture?

BACKGROUND

Meningitis can be caused by several viruses and bacteria. Identifying the causative pathogen as quickly as possible is crucial to initiate the most optimal therapy, as acute bacterial meningitis is associated with a significant morbidity and mortality. Bacterial meningitis requires antibiotics, as opposed to enteroviral meningitis, which only requires supportive therapy. Clinical presentation is usually not sufficient to differentiate between viral and bacterial meningitis, thereby necessitating cerebrospinal fluid (CSF) analysis by PCR and/or time-consuming bacterial cultures. However, collecting CSF in children is not always feasible and a rather invasive procedure.

METHODS

In 12 Belgian hospitals, we obtained acute blood samples from children with signs of meningitis (49 viral and 7 bacterial cases) (aged between 3 months and 16 years). After pathogen confirmation on CSF, the patient was asked to give a convalescent sample after recovery. 3' mRNA sequencing was performed to determine differentially expressed genes (DEGs) to create a host transcriptomic profile.

RESULTS

Enteroviral meningitis cases displayed the largest upregulated fold change enrichment in type I interferon production, response and signaling pathways. Patients with bacterial meningitis showed a significant upregulation of genes related to macrophage and neutrophil activation. We found several significantly DEGs between enteroviral and bacterial meningitis. Random forest classification showed that we were able to differentiate enteroviral from bacterial meningitis with an AUC of 0.982 on held-out samples.

CONCLUSIONS

Enteroviral meningitis has an innate immunity signature with type 1 interferons as key players. Our classifier, based on blood host transcriptomic profiles of different meningitis cases, is a possible strong alternative for diagnosing enteroviral meningitis.

Exhaled breath metabolomics reveals a pathogen-specific response in a rat pneumonia model for two human pathogenic bacteria: a proof-of-concept study

Volatile organic compounds in breath can reflect host and pathogen metabolism and might be used to diagnose pneumonia. We hypothesized that rats with Streptococcus pneumoniae ( SP) or Pseudomonas aeruginosa ( PA) pneumonia can be discriminated from uninfected controls by thermal desorption-gas chromatography-mass-spectrometry (TD-GC-MS) and selected ion flow tube-mass spectrometry (SIFT-MS) of exhaled breath. Male adult rats ( n = 50) received an intratracheal inoculation of 1) 200 µl saline, or 2) 1 × 107 colony-forming units of SP or 3) 1 × 107 CFU of PA. Twenty-four hours later the rats were anaesthetized, tracheotomized, and mechanically ventilated. Exhaled breath was analyzed via TD-GC-MS and SIFT-MS. Area under the receiver operating characteristic curves (AUROCCs) and correct classification rate (CCRs) were calculated after leave-one-out cross-validation of sparse partial least squares-discriminant analysis. Analysis of GC-MS data showed an AUROCC (95% confidence interval) of 0.85 (0.73–0.96) and CCR of 94.6% for infected versus noninfected animals, AUROCC of 0.98 (0.94–1) and CCR of 99.9% for SP versus PA, 0.92 (0.83–1.00), CCR of 98.1% for SP versus controls and 0.97 (0.92–1.00), and CCR of 99.9% for PA versus controls. For these comparisons the SIFT-MS data showed AUROCCs of 0.54, 0.89, 0.63, and 0.79, respectively. Exhaled breath analysis discriminated between respiratory infection and no infection but with even better accuracy between specific pathogens. Future clinical studies should not only focus on the presence of respiratory infection but also on the discrimination between specific pathogens.

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.].

The Sustained Rotavirus Vaccination Impact on Nosocomial Infection, Duration of Hospital Stay, and Age: The RotaBIS Study (2005-2012)

Introduction

The benefits of rotavirus (RV) vaccination in developed countries have focused on reductions in mortality, hospitalization and medical visits, and herd protection. We investigated other aspects related to RV-induced nosocomial infection, duration of hospital stay, age shift, and sustained vaccine impact (VI) over time.

Method

RotaBIS (Rotavirus Belgian Impact Study; ClinicalTrials.gov identifier, NCT01563146) annually collects retrospective data on hospitalization linked to RV testing in children up to 5 years old from 11 pediatric wards located all over Belgium. Data from 2005 to 2012 have been split in pre- (2005–2006) and post-vaccination (2007–2012) period. Information was collected on age, gender, RV test result, nosocomial infection caused by RV and duration of hospital stay.

Results

Over the 6-year period after the introduction of the RV vaccine, an 85% reduction in nosocomial infections was observed (221 in 2005 to 33 in 2012, p < 0.001). A significant reduction of almost 2 days in average duration of hospital stay per event was observed overall (7.62 days in 2005 to 5.77 days in 2012, p < 0.001). The difference is mainly explained by the higher reduction in number of nosocomial infections. A pronounced age shift (+24%, p < 0.01) of RV nosocomial infection to infants ≤2 months old was observed, increasing with length of post-vaccination period. VI was maintained over the follow-up (±79% VI per birth cohort). A decrease was seen depending on age, 85% (95% CI 76–91%) in the youngest to 63% (95% CI 22–92%) in the oldest age group.

Conclusion

The higher reduction in nosocomial infection may affect the overall average duration of hospital stay for RV infection. No change in VI by birth cohort, but a reduction by age group was observed. These findings could be important for decision-makers considering the introduction of universal mass RV vaccination programs.

Trial registration

ClinicalTrials.gov identifier, NCT01563146.

Funding

GlaxoSmithKline Biologicals SA (Rixensart, Belgium).

Identification of specific bovine blood biomarkers with a non-targeted approach using HPLC ESI tandem mass spectrometry

Animal by-products are valuable protein sources in animal nutrition. Among them are blood products and blood meal, which are used as high-quality material for their beneficial effects on growth and health. Within the framework of the feed ban relaxation, the development of complementary methods in order to refine the identification of processed animal proteins remains challenging. The aim of this study was to identify specific biomarkers that would allow the detection of bovine blood products and processed animal proteins using tandem mass spectrometry. Seventeen biomarkers were identified: nine peptides for bovine plasma powder; seven peptides for bovine haemoglobin powder, including six peptides for bovine blood meal; and one peptide for porcine blood. They were not detected in several commercial compound feed or feed materials, such as blood by-products of other animal origins, milk-derived products and fish meal. These biomarkers could be used for developing a species-specific and blood-specific detection method.

Species and tissues specific differentiation of processed animal proteins in aquafeeds using proteomics tools

The rapidly growing aquaculture industry drives the search for sustainable protein sources in fish feed. In the European Union (EU) since 2013 non-ruminant processed animal proteins (PAP) are again permitted to be used in aquafeeds. To ensure that commercial fish feeds do not contain PAP from prohibited species, EU reference methods were established. However, due to the heterogeneous and complex nature of PAP complementary methods are required to guarantee the safe use of this fish feed ingredient. In addition, there is a need for tissue specific PAP detection to identify the sources (i.e. bovine carcass, blood, or meat) of illegal PAP use. In the present study, we investigated and compared different protein extraction, solubilisation and digestion protocols on different proteomics platforms for the detection and differentiation of prohibited PAP. In addition, we assessed if tissue specific PAP detection was feasible using proteomics tools. All work was performed independently in two different laboratories. We found that irrespective of sample preparation gel-based proteomics tools were inappropriate when working with PAP. Gel-free shotgun proteomics approaches in combination with direct spectral comparison were able to provide quality species and tissue specific data to complement and refine current methods of PAP detection and identification.

SIGNIFICANCE

To guarantee the safe use of processed animal protein (PAP) in aquafeeds efficient PAP detection and monitoring tools are required. The present study investigated and compared various proteomics workflows and shows that the application of shotgun proteomics in combination with direct comparison of spectral libraries provides for the desired species and tissue specific classification of this heat sterilized and pressure treated (≥133°C, at 3bar for 20min) protein feed ingredient.

Improvement in hospital Quality of Care (QoC) after the introduction of rotavirus vaccination: An evaluation study in Belgium

During each winter period hospital emergency rooms and pediatric wards are often overwhelmed by high patient influx with infectious diseases leading to chaotic conditions with poor quality of care (QoC) delivery as a consequence. The conditions could be improved if we were able to better control the influx by introducing for instance better prevention strategies against some of the most frequent infectious diseases. New prevention strategies using vaccination against rotavirus infection were introduced in Belgium in November 2006. We developed a measure of hospital QoC suitable for assessing the impact of pediatric rotavirus vaccination. The study is retrospective collecting routine data on bed and staff management in one pediatric hospital in Belgium. The data were divided in pre- and post-vaccination periods during rotavirus-epidemic and non-epidemic periods. The scores were constructed using Explanatory Factor Analysis (EFA). All patients enrolled were admitted to the pediatric ward over the period from 1 January 2004 to 31 December 2009. The results of the epidemic period indicated that bed-day occupancy, bed-day turnover and unplanned readmissions for acute gastroenteritis were lower in the post-vaccination compared with the pre-vaccination periods. The QoC scores were therefore significantly lower (indicating improved QoC) after the introduction of rotavirus vaccination, compared with pre-vaccination. The data suggests that the reduction in the winter peak of rotavirus-related hospitalizations after the introduction of the vaccine reduces pressure on hospital resources and improves the quality of hospital care. The findings should be further tested in similar settings.

Medium- to Long-Term Impact of Rotavirus Vaccination on Hospital Care in Belgium: A 7-Year Follow-Up of the Rotavirus Belgium Impact Study (RotaBIS)

Introduction

Rotavirus (RV) vaccination was introduced in Belgium in 2006. With the high uptake it had (>85%), a sharp decline in hospitalizations was observed during the first years after vaccine introduction. The objective of this study was to investigate whether this decline was maintained and to simulate projections.

Methods

The Rotavirus Belgium Impact Study allowed an analysis of the RV vaccine impact amongst children in 11 hospitals in Belgium over a 9-year period (2005–2013) with 2 years pre- and 7 years post-vaccine introduction. Results were compared by year and by subsequent birth cohort aging up to 5 years. The two different analysis methods helped dismantling the different (direct and indirect) effects of vaccine protection to simulate future hospitalization trends.

Results

During the whole observation period, 40,552 RV detection tests were performed of which 5832 were positive (14.4%). After RV vaccine introduction, a significant reduction in number of tests performed (−38%) was combined with a dramatic drop in numbers of positive tests (−76.6%). The decreases were spectacular during the first two years of vaccine introduction; after that period, the decrease flattened. Cross-sectional comparison with cohort data showed that the initial drop was heavily influenced by the herd effect of the vaccine. Cohort analysis demonstrated a low rate of residual disease over time, suggesting another infection source other than the child population.

Conclusion

The residual disease will be maintained in the community when a same vaccination strategy is continued over time, starting vaccination of children only at 6 weeks’ time.

Funding

GlaxoSmithKline Biologicals SA.

Trial registration

ClinicalTrials.gov identifier, NCT01563146.

Electronic supplementary material

The online version of this article (doi:10.1007/s40121-015-0099-1) contains supplementary material, which is available to authorized users.

Importance of preoperative anaesthetic consultation in perioperative medicine

This report describes two patients for whom the preoperative, anaesthetic consultation led to postponing planned surgery because of important, undiagnosed health problems. In one of the two cases, this consultation was even life-saving. However, actual literature cannot prove any advantage on the outcome of the individual patient. The only proven advantages in favour of pre-operative consultation are a reduced length of stay in the hospital and a reduction in the cost of preoperative testing.

Influence of domestication process on immune response to repeated emersion stressors in Eurasian perch (Perca fluviatilis, L.)

Domestication might be a possible way to reduce the physiological response to long-term stressors and deleterious effects on immunity. The present study aimed to evaluate the chronic immune response induced by repeated emersions and the possible impact of domestication by comparing farmed Eurasian perch with short (F1) and long (F4) captive-life history. In the first experiment, fish were exposed to a single emersion and physiological stress response was measured in the short term to characterize fish sensitivity to the tested stressor. Serum cortisol and glucose elevated within 6h post-stress and splenosomatic index (SSI) decreased within 48h, indicating that the species was affected by emersion stressor. In the second experiment, F1 and F4 generations were submitted to repeated water emersions (3 times/week during 44days). On day 9, 18 and 44, samplings were performed 48h post-stressor to highlight any sustained disruption of immune system. Serum cortisol, glucose, SSI and lysozyme activity were evaluated and serum proteome was analyzed using 2D-DIGE. Any of the tested variables were affected by repeated emersions and proteomic analysis only revealed that alpha-2 macroglobulins (a2Ms) were up-regulated in the serum of stressed individuals. Domestication also resulted in the up-regulation of five a2M isoforms and down-regulation of complement C3 and Ig light chain proteins, independently of any stressor exposure. In conclusion, the results suggested that repeated emersions are not severe stressors for Eurasian perch, probably explaining why domestication had no influence on fish responses. Changes associated with domestication are highly complex and certainly need further investigations.

Myeloperoxidase and its products in synovial fluid of patients with treated or untreated rheumatoid arthritis

OBJECTIVE

Plasma and synovial myeloperoxidase (MPO) and its products were strongly associated with osteoarthritis (OA) and rheumatoid arthritis (RA). In addition, it is well known that there is a link between oxidative stress and cytokines. The present study aims at investigating the link between synovial MPO (and its products), interleukin (IL)-18, which is involved in the degradation of articular cartilage in RA, and IL-8, which is involved in recruitment and activation of neutrophils during inflammation. Effects of the treatment of RA on the biological parameters were also investigated.

METHODS

Patients (n = 105) were studied including 39 patients with OA, 33 with RA and 33 with RA receiving a specific treatment. Disease activity score (DAS-28) was calculated whereas MPO antigen/activity, neutrophils, chloro-tyrosine (Cl-Tyr), homocitrulline (Hcit), IL-8, and IL-18 were measured in synovial fluid (SF) and CRP was measured in serum.

RESULTS

DAS-28 and CRP levels were not significantly different between groups. MPO activity, and MPO, Cl-Tyr, and Hcit levels were significantly higher in SF of RA patients than OA patients. MPO specific activity (MPO activity/antigen ratio) was significantly lower in treated than in untreated RA patients as was IL-8. MPO activity and concentration were correlated with IL-8 and IL-18 in untreated but not in treated RA patients.

CONCLUSIONS

MPO level is related to IL-8 and IL-18 levels in untreated RA patients. A link has been shown between treatment and decrease of IL-8, MPO specific activity and Hcit in SF. The causal role of MPO in SF inflammation and how treatment can affect MPO specific activity need further investigations.

Numerical characterization of an ultra-high NA coherent fiber bundle part I: modal analysis

Advances in fiber optics and CCD technology in the last decades have allowed for a large reduction in outer diameter (from centimeters to submillimeter) of endoscopes. Attempts to reduce the outer diameter even further, however, have been hindered by the trade-off, inherent to conventional endoscopes, between outer diameter, resolution and field of view. Several groups have shown the feasibility of further miniaturization towards so called micro-endoscopes, albeit at the cost of a very reduced field of view. In previous work we presented the design of an ultra-high NA (0.928) Coherent FiberBundle (CFB) that, in combination with proximal wave front shaping, could be used to circumvent this trade-off thus paving the way for even smaller endoscopes. In this paper we analyze how the modal properties of such an ultra-high NA CFB determine the required input field to achieve any desired output field. We use the periodicity of the hexagonal lattice which characterizes a CFB, to define a unit cell of which we analyze the eigen-modes. During the modal analysis, we also take into account realistic variations in lattice constant, core size and core shape due to the limitations of the fabrication technology. Realistic values for these types of fabrication-induced irregularities were obtained via SEM images of a CFB fabricated according to the aforementioned design. The presence of these irregularities results, for a desired output, in the required input to be different from the required input for a defect-free CFB. We find that of the different types of fabrication-induced irregularities present in the CFB, variations in core ellipticity have the biggest impact on the required input for a given desired output.

Impact of rotavirus vaccination on hospitalisations in Belgium: comparing model predictions with observed data

Background

Published economic assessments of rotavirus vaccination typically use modelling, mainly static Markov cohort models with birth cohorts followed up to the age of 5 years. Rotavirus vaccination has now been available for several years in some countries, and data have been collected to evaluate the real-world impact of vaccination on rotavirus hospitalisations. This study compared the economic impact of vaccination between model estimates and observed data on disease-specific hospitalisation reductions in a country for which both modelled and observed datasets exist (Belgium).

Methods

A previously published Markov cohort model estimated the impact of rotavirus vaccination on the number of rotavirus hospitalisations in children aged <5 years in Belgium using vaccine efficacy data from clinical development trials. Data on the number of rotavirus-positive gastroenteritis hospitalisations in children aged <5 years between 1 June 2004 and 31 May 2006 (pre-vaccination study period) or 1 June 2007 to 31 May 2010 (post-vaccination study period) were analysed from nine hospitals in Belgium and compared with the modelled estimates.

Results

The model predicted a smaller decrease in hospitalisations over time, mainly explained by two factors. First, the observed data indicated indirect vaccine protection in children too old or too young for vaccination. This herd effect is difficult to capture in static Markov cohort models and therefore was not included in the model. Second, the model included a ‘waning’ effect, i.e. reduced vaccine effectiveness over time. The observed data suggested this waning effect did not occur during that period, and so the model systematically underestimated vaccine effectiveness during the first 4 years after vaccine implementation.

Conclusions

Model predictions underestimated the direct medical economic value of rotavirus vaccination during the first 4 years of vaccination by approximately 10% when assessing hospitalisation rates as compared with observed data in Belgium.

Effectiveness of rotavirus vaccination in prevention of hospital admissions for rotavirus gastroenteritis among young children in Belgium: case-control study

OBJECTIVE

To evaluate the effectiveness of rotavirus vaccination among young children in Belgium.

DESIGN

Prospective case-control study.

SETTING

Random sample of 39 Belgian hospitals, February 2008 to June 2010.

PARTICIPANTS

215 children admitted to hospital with rotavirus gastroenteritis confirmed by polymerase chain reaction and 276 age and hospital matched controls. All children were of an eligible age to have received rotavirus vaccination (that is, born after 1 October 2006 and aged ≥ 14 weeks).

MAIN OUTCOME MEASURE

Vaccination status of children admitted to hospital with rotavirus gastroenteritis and matched controls.

RESULTS

99 children (48%) admitted with rotavirus gastroenteritis and 244 (91%) controls had received at least one dose of any rotavirus vaccine (P<0.001). The monovalent rotavirus vaccine accounted for 92% (n=594) of all rotavirus vaccine doses. With hospital admission as the outcome, the unadjusted effectiveness of two doses of the monovalent rotavirus vaccine was 90% (95% confidence interval 81% to 95%) overall, 91% (75% to 97%) in children aged 3-11 months, and 90% (76% to 96%) in those aged ≥ 12 months. The G2P[4] genotype accounted for 52% of cases confirmed by polymerase chain reaction with eligible matched controls. Vaccine effectiveness was 85% (64% to 94%) against G2P[4] and 95% (78% to 99%) against G1P[8]. In 25% of cases confirmed by polymerase chain reaction with eligible matched controls, there was reported co-infection with adenovirus, astrovirus and/or norovirus. Vaccine effectiveness against co-infected cases was 86% (52% to 96%). Effectiveness of at least one dose of any rotavirus vaccine (intention to vaccinate analysis) was 91% (82% to 95%).

CONCLUSIONS

Rotavirus vaccination is effective for the prevention of admission to hospital for rotavirus gastroenteritis among young children in Belgium, despite the high prevalence of G2P[4] and viral co-infection.

Secondary soy allergy in children with birch pollen allergy may cause both chronic and acute symptoms

BACKGROUND

Secondary soy allergy occurring in tree pollen allergic patients may cause acute symptoms.

METHODS

We selected children with birch pollen allergy suspected of also being soy allergic (SA). Soy allergy was proven based on one of the following: (i) a clear-cut clinical history; (ii) a positive provocation test; and (iii) elimination and reintroduction of soy. Skin prick tests (SPT) were performed with a commercial soy extract and with soy flour. Specific IgE to Gly m 4, Gly m 5, and Gly m 6 was determined by means of ImmunoCAP and ISAC. Eight soy-tolerant atopic children being CAP rGly m 4-negative served as a control group for skin testing.

RESULTS

Of 15 subjects with birch pollen allergy and being suspected of soy allergy, eight of them proved to be SA; 7/15 subjects proved to be soy tolerant (ST). Besides acute symptoms in 8/8 SA subjects, 3/8 subjects also had been suffering from severe chronic complaints because of soy allergy. SPT with commercial soy extract was negative in all SA and ST subjects tested. SPT with soy flour was positive in 8/8 SA and in 5/6 ST subjects, but negative in all 8 controls (p < 0.0001); the median weal diameter was 7.7 mm in SA subjects, compared to 3 mm in ST subjects (p < 0.01). The median IgE level to rGly m 4 using CAP and ISAC was, respectively, 32.4 kU/l and 4.0 ISU in SA subjects, compared to 6.2 kU/l and 0.4 ISU in ST subjects (p < 0.05). Analysis of IgE to nGly m 5 and nGly m 6, using CAP or ISAC, showed no significant differences between SA and ST subjects.

CONCLUSIONS

Secondary soy allergy may cause severe chronic besides acute symptoms. SPT with soy flour is a sensitive and specific tool in detecting soy sensitization. SPT with soy flour, CAP rGly m 4, and ISAC rGLY m 4 are valuable tools in the diagnosis of birch-pollen-associated secondary soy allergy.

Physiological and proteomic evidences that domestication process differentially modulates the immune status of juvenile Eurasian perch (Perca fluviatilis) under chronic confinement stress

The current study aimed to evaluate the influence of domestication process on the stress response and subsequent immune modulation in Eurasian perch juveniles (Perca fluviatilis) submitted to chronic confinement. Briefly, F1 and F4 generations were confined into small-size tanks and sampled 7 and 55 days after stocking. Cortisol and glucose levels as well as lysozyme activity and immunoglobulin level were evaluated in the serum. Spleen Somatic Index and spleen ROS production were also measured. A proteomic analysis was performed on serum sampled on day 7. Finally, both generations were genetically characterized using a microsatellite approach. Globally, results revealed that chronic confinement did not elicit a typical stress response but resulted in a prolonged immune stimulation. Proteomic results suggested that domestication process influenced the immune status of perch submitted to chronic confinement as the F1 confined fish displayed lower abundance of C3 complement component, transferrin and Apolipoprotein E. Microsatellite data showed a strong genetic drift as well as reduced genetic diversity, allelic number and heterozygosity along with domestication process. The present work is the first to report that fish under domestication can develop an immune response, assessed by a combined approach, following recurrent challenges imposed by captive environment despite a reduced genetic variation.

Efficacy of combined porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae vaccination in piglets

Three vaccination challenge studies were performed to evaluate the impact on vaccine efficacy of combining porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae vaccines. Piglets were vaccinated with either a M hyopneumoniae bacterin, a modified live PRRSV vaccine based on a European-type PRRSV strain, or a combination of both vaccines, followed by experimental infection with either M hyopneumoniae or PRRSV. Vaccine efficacy was evaluated by assessing lung lesion scores for M hyopneumoniae and measuring viraemia for PRRSV. There were no significant differences between the protective efficacy of the combined vaccine protocol and the protective efficacy of the two single vaccines, indicating that PRRSV vaccination did not interfere with M hyopneumoniae vaccine efficacy and vice versa.

Exploration of basal immune parameters in healthy infants receiving an infant milk formula supplemented with prebiotics

This double-blind, randomized, placebo-controlled study, aimed to explore the effect of an infant milk formula (IMF) with 6 g/l short-chain galacto- and long-chain fructo-oligosaccharides (scGOS/lcFOS, ratio 9:1) on basal immune parameters in 215 healthy, term infants during the first 26 wk of life. After birth, the infants received breast milk or were randomized to receive an IMF with or without scGOS/lcFOS. Blood samples were collected at the age of 8 wk and 26 wk for the analysis of serum immunoglobulins, lymphocyte subpopulations, and cytokines. The scGOS/lcFOS group and the control group were compared in the statistical analysis. A breast fed group was included as a reference. In total, 187 Infants completed the study. No significant differences were observed between both formula groups in the different studied immune parameters at weeks 8 and 26. This explorative study indicates that supplementation of infant formula with a mixture of prebiotic oligosaccharides did not change the basal level of the measured parameters of the developing immune system in healthy infants with a balanced immune system during the first 6 months of life in comparison to feeding a standard infant formula and in comparison to exclusive breastfeeding.

Laboratory diagnosis of specific antibody deficiency to pneumococcal capsular polysaccharide antigens by multiplexed bead assay

We evaluated a multiplexed bead-based assay (xMAP Pneumococcal Immunity assay from Luminex) for the simultaneous determination of antibodies against 14 capsular polysaccharides. Post-vaccination (Pneumovax) antibody concentrations were measured in 35 healthy children, 40 healthy adults, 99 consecutive patients with increased susceptibility to respiratory infection, and 24 patients with a deficient anti-polysaccharide antibody response. The serotype-specific lower 5th percentile (cutoff) value for the post-immunization antibody concentration was determined in healthy individuals. Eleven of 99 patients (11%) failed to mount a response that was >5th percentile of controls for at least 6 of the 14 serotypes tested, whereas only 3 of 75 controls (4%) failed to do so. All patients with known anti-polysaccharide antibody deficiency failed to mount a response that was >5th percentile of controls for at least 6 of the 14 serotypes tested. The XMAP pneumococcal immunity panel appears useful for identifying individuals with a low response to the unconjugated pneumococcal vaccine.

Montelukast does not prevent reactive airway disease in young children hospitalized for RSV bronchiolitis

AIM

To evaluate the long-term effect of montelukast on symptoms of cough and wheeze following RSV bronchiolitis.

METHODS

Fifty eight patients (aged < or = 24 months) hospitalized with a first episode of RSV bronchiolitis were enrolled in this double blind prospective randomized trial comparing montelukast (n = 31) vs placebo (n = 27).

RESULTS

During the 3-month treatment period, there were no statistical significant differences between the two groups for symptom-free days and nights (48.5 [interquartile range 33.0.0-66.0] for montelukast vs 57.0 [29.0-71.0] for placebo p = 0.415) nor disease-free days and nights (44.5 days [26.0-54.0] vs 53.0 [22.3-71.0]; p = 0.266). During the 1 year follow-up, there were 41 exacerbations in the montelukast group vs 54 exacerbations in the placebo group (p = 0.57). Time to first exacerbation was not different. Number of unscheduled visits and need to start inhaled steroids were comparable in the two groups.

CONCLUSION

Treatment with montelukast after hospital admission for RSV bronchiolitis in children younger than 2 years of age did not reduce symptoms of cough and wheeze. We cannot exclude that a subgroup of children may, however, benefit from this treatment.

Forced catch-up growth after fetal protein restriction alters the adipose tissue gene expression program leading to obesity in adult mice

A mismatch between fetal and postnatal environment can permanently alter the body structure and physiology and therefore contribute later to obesity and related disorders, as revealed by epidemiological studies. Early programming of adipose tissue might be central in this observation. Moreover, adipose tissue secretes adipokines that provide a molecular link between obesity and its related disorders. Therefore, our aim was to investigate whether a protein restriction during fetal life, followed by catch-up growth could lead to obesity in 9-mo-old male mice and could alter the adipose tissue gene expression profile. Dams were fed a low-protein (LP) or an isocaloric control (C) diet during gestation. Postnatal catch-up growth was induced in LP offspring by feeding dams with control diet and by culling LP litters to four pups instead of eight in the C group. At weaning, male mice were fed by lab chow alone (C) or supplemented with a hypercaloric diet (HC), to induce obesity (C-C, C-HC, LP-C, and LP-HC groups). At 9 mo, LP offspring featured increased relative fat mass, hyperglycemia, hypercholesterolemia, and hyperleptinemia. Using a microarray designed to study the expression of 89 genes involved in adipose tissue differentiation/function, we demonstrated that the expression profile of several genes were dependent upon the maternal diet. Among the diverse genes showing altered expression, we could identify genes encoding several enzymes involved in lipid metabolism. These results indicated that offspring submitted to early mismatched nutrition exhibited alterations in adipose tissue gene expression that probably increases their susceptibility to overweight when challenged after weaning with a HC diet.