Fibrotic and Emphysematous Murine Lung Mechanics Under Negative-Pressure Ventilation.

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide and the progressive nature heightens the calamity of the disease. Despite countless existing COPD studies, lung mechanics are often reported under positive-pressure ventilation (PPV) and implications and extrapolations made from these studies pose serious restrictions as recent works have divulged disparate elastic and energetic results between PPV and more physiological negative-pressure counterparts (NPV). This non-equivalence of PPV and NPV needs to be investigated under diseased states to augment our understanding of disease mechanics.

Lung Mechanics: Material Characterization of Pulmonary Constituents for an Experimentally Informed Computational Pipeline.

The lung comprises multiple components including the parenchyma, airways, and visceral pleura, where each constituent displays specific material properties that together govern the whole organ's properties. The structural and mechanical complexity of the lung has historically undermined its comprehensive characterization, especially compared to other biological organs, such as the heart or bones. This knowledge void is particularly remarkable when considering that pulmonary disease is one of the leading causes of morbidity and mortality across the globe.

A Comparative Study of Ex-Vivo Murine Pulmonary Mechanics Under Positive- and Negative-Pressure Ventilation.

Increased ventilator use during the COVID-19 pandemic resurrected persistent questions regarding mechanical ventilation including the difference between physiological and artificial breathing induced by ventilators (i.e., positive- versus negative-pressure ventilation, PPV vs NPV).

Diseased and healthy murine local lung strains evaluated using digital image correlation.

Tissue remodeling in pulmonary disease irreversibly alters lung functionality and impacts quality of life. Mechanical ventilation is amongst the few pulmonary interventions to aid respiration, but can be harmful or fatal, inducing excessive regional (i.e.

Associating local strains to global pressure-volume mouse lung mechanics using digital image correlation.

Pulmonary diseases alter lung mechanical properties, can cause loss of function, and necessitate use of mechanical ventilation, which can be detrimental. Investigations of lung tissue (local) scale mechanical properties are sparse compared to that of the whole organ (global) level, despite connections between regional strain injury and ventilation. We examine ex vivo mouse lung mechanics by investigating strain values, local compliance, tissue surface heterogeneity, and strain evolutionary behavior for various inflation rates and volumes.

Mouse lung mechanical properties under varying inflation volumes and cycling frequencies.

Respiratory pathologies alter the structure of the lung and impact its mechanics. Mice are widely used in the study of lung pathologies, but there is a lack of fundamental mechanical measurements assessing the interdependent effect of varying inflation volumes and cycling frequency. In this study, the mechanical properties of five male C57BL/6J mice (29-33 weeks of age) lungs were evaluated ex vivo using our custom-designed electromechanical, continuous measure ventilation apparatus.

Examining lung mechanical strains as influenced by breathing volumes and rates using experimental digital image correlation.

Background: Mechanical ventilation is often employed to facilitate breathing in patients suffering from respiratory illnesses and disabilities. Despite the benefits, there are risks associated with ventilator-induced lung injuries and death, driving investigations for alternative ventilation techniques to improve mechanical ventilation, such as multi-oscillatory and high-frequency ventilation; however, few studies have evaluated fundamental lung mechanical local deformations under variable loading.

Methods: Porcine whole lung samples were analyzed using a novel application of digital image correlation interfaced with an electromechanical ventilation system to associate the local behavior to the global volume and pressure loading in response to various inflation volumes and breathing rates.

Effectiveness of interventions for the reversal of a metabolic syndrome diagnosis: An update of a meta-analysis of mixed treatment comparison studies.

Introduction: Identifying the most effective interventions to reverse the metabolic syndrome can be key in the design of clinical strategies to prevent progression to type 2 diabetes mellitus and cardiovascular disease. Objective: To estimate the effect size of the interventions used for the reversal of metabolic syndrome. Materials and methods: We searched in Embase and Medline databases for randomized clinical trials with an outcome defined as the reversal of the metabolic syndrome diagnosis.