The relationship between added lung sounds and airway dimensions

The aim of this study was to explore potential relationships between added lung sound characteristics measured by Computer Aided Lung Sound Analysis (CALSA) and airway dimensions measured by High resolution Computed Tomography (HRCT). CALSA has been proposed as a new objective measurement to record and analyse lung sounds. However, there is still a lack of evidence as to whether and how added lung sounds relate to the geometry of airways. HRCT is considered to have the highest sensitivity of imaging measurements and is capable of generating three dimensional pictures of airways from which the dimensions may be measured. Twenty-six participants (9 healthy non-smokers, 9 healthy smokers and 8 patients with COPD) were recruited. Lung sound data were recorded using a digital stethoscope. HRCT scans were conducted using a Siemens Sensation 64 CT scanner and the resulting data were analysed using the Pulmonary Workstation 2 software to give airway dimensions. Lungs sounds were characterised in terms of Crackle 2-cycle durations (crackle 2CD), the number of crackles per breathing cycle (NCpB) and lung geometry were characterised in terms of airway diameter, length, branching angle, internal perimeter, wall thickness and percentage of wall area. The analysis showed that there was a significant positive correlation between crackle 2CD and airway wall thickness at generations 3 and 5. Crackle 2CD also significantly correlated with the branching angles at the main bronchus and at generation 3. There was also a significant negative correlation between NCpB and percentage of wall area at generation 2 and airway wall thickness at generation 5. Moreover, NCpB recorded at anterior right region of chest wall was found to predict the percentage of wall area at the right upper bronchus. These initial results suggest NCpB might be useful to predict changes in percentage of wall area caused by the chronic inflammation of the main bronchi, though a larger sample size would be needed to confirm it. This suggests that crackles could potentially be used as a biomarker of COPD

Bacterial challenge-associated metabolic phenotypes in Hermetia illucens defining nutritional and functional benefits

Black soldier fly (BSF, Hermetia illucens) is popular for its applications in animal feed, waste management and antimicrobial peptide source. The major advantages of BSF larva include their robust immune system and high nutritional content that can be further developed into more potential agricultural and medical applications. Several strategies are now being developed to exploit their fullest capabilities and one of these is the immunity modulation using bacterial challenges. The mechanism underlying metabolic responses of BSF to different bacteria has, however, remained unclear. In the current study, entometabolomics was employed to investigate the metabolic phenoconversion in response to either Escherichia coli, Staphylococcus aureus, or combined challenges in BSF larva. We have, thus far, characterized 37 metabolites in BSF larva challenged with different bacteria with the major biochemical groups consisting of amino acids, organic acids, and sugars. The distinct defense mechanism-specific metabolic phenotypes were clearly observed. The combined challenge contributed to the most significant metabolic phenoconversion in BSF larva with the dominant metabolic phenotypes induced by S. aureus. Our study suggested that the accumulation of energy-related metabolites provided by amino acid catabolism is the principal metabolic pathway regulating the defense mechanism. Therefore, combined challenge is strongly recommended for raising BSF immunity as it remarkably triggered amino acid metabolisms including arginine and proline metabolism and alanine, aspartate and glutamate metabolism along with purine metabolism and pyruvate metabolism that potentially result in the production of various nutritional and functional metabolites