Impact of short term forced oral breathing induced by nasal occlusion on respiratory function in mice

Aerosolized delivery of ESKAPE pathogens for murine pneumonia models

Murine pneumonia models for ESKAPE pathogens serve to evaluate novel antibacterials or to investigate immunological responses. The majority of published models uses intranasal or to a limited extent the intratracheal instillation to challenge animals. In this study, we propose the aerosol delivery of pathogens using a nebulizer. Aerosol delivery typically results in homogeneous distribution of the inoculum in the lungs because of lower particle size. This is of particular importance when compounds are assessed for their pharmacokinetic and pharmacodynamic (PK/PD) relationships as it allows to conduct several analysis with the same sample material. Moreover, aerosol delivery has the advantage that it mimics the 'natural route' of respiratory infection. In this short and concise study, we show that aerosol delivery of pathogens resulted in a sustained bacterial burden in the neutropenic lung infection model for five pathogens tested, whereas it gave a similar result in immunocompetent mice for three out of five pathogens. Moreover, a substantial bacterial burden in the lungs was already achieved 2 h post inhalation. Hence, this study constitutes a viable alternative for intranasal administration and a refinement of murine pneumonia models for PK/PD assessments of novel antibacterial compounds allowing to study multiple readouts with the same sample material.

Influence of mouth breathing on atopic dermatitis risk and oral health in children: A population-based cross-sectional study

Background/purpose

Previous studies have suggested that mouth breathing has harmful effects on atopic dermatitis (AD) and oral health in children, but the evidence has been insufficient. To investigate the association of mouth breathing with AD and oral health in Korean schoolchildren aged 8–11 years.

Materials and methods

Cross-sectional data were obtained from March to April 2016. A questionnaire was used to investigate children's mouth breathing habits and personal/family histories related to allergic disease. Oral health status was determined through a clinical oral examination. Data were analyzed with multivariable logistic regression.

Results

In total, 1507 children were included. A moderate relationship was observed between mouth breathing and AD (adjusted odds ratio, 1.05; 95% confidence interval, 1.00–1.10; p-value, 0.035), whereas no association was found between mouth breathing and dental caries in children. Mouth breathing during sleep (MBS) was closely related to allergic diseases and other respiratory diseases. Furthermore, mouth breathing was associated with child's tonsillitis and was identified as a possible risk factor for class II dental malocclusion.

Conclusion

We confirmed the positive association between mouth breathing (especially during sleep) and allergic diseases, including the AD in school-aged children. The influence of mouth breathing on dental caries remains uncertain. An intervention trial is required to evaluate whether the prevention of mouth breathing can reduce the risk of allergic diseases.

Fatal Aspergillus flavus rhinitis with gastrointestinal gaseous distension in a Cape porcupine

An adult female Cape porcupine (Hystrix africaeaustralis) was presented because of marked abdominal distension, acute dyspnea, and lethargy. Physical examination and standard radiographs revealed marked and diffuse gaseous dilation of the stomach and intestines of undetermined origin. The porcupine died despite medical therapy and surgical intervention. Postmortem examination revealed chronic fungal (Aspergillus flavus) rhinitis. Given that rodents are obligate nasal breathers, the rhinitis likely resulted in substantial upper airway obstruction leading to aerophagia.