Matriptase proteolytically activates influenza virus and promotes multicycle replication in the human airway epithelium.

Influenza viruses do not encode any proteases and must rely on host proteases for the proteolytic activation of their surface hemagglutinin proteins in order to fuse with the infected host cells. Recent progress in the understanding of human proteases responsible for influenza virus hemagglutinin activation has led to the identification of members of the type II transmembrane serine proteases TMPRSS2 and TMPRSS4 and human airway trypsin-like protease; however, none has proved to be the sole enzyme responsible for hemagglutinin cleavage. In this study, we identify and characterize matriptase as an influenza virus-activating protease capable of supporting multicycle viral replication in the human respiratory epithelium.

Measurement of fractional order model parameters of respiratory mechanical impedance in total liquid ventilation.

This study presents a methodology for applying the forced-oscillation technique in total liquid ventilation. It mainly consists of applying sinusoidal volumetric excitation to the respiratory system, and determining the transfer function between the delivered flow rate and resulting airway pressure. The investigated frequency range was f ∈ [0.

Total liquid ventilation efficacy in an ovine model of severe meconium aspiration syndrome.

Objective: To test the hypothesis that total liquid ventilation enables a more effective and better tolerated lavage than a bronchoalveolar lavage performed with diluted surfactant in a newborn ovine model of severe acute meconium aspiration syndrome.

Design: Prospective, randomized, interventional study.

Setting: Animal research laboratory at the Faculté de médecine et des sciences de la santé de l'université de Sherbrooke, Sherbrooke, Canada.

Neonatal total liquid ventilation: is low-frequency forced oscillation technique suitable for respiratory mechanics assessment?

This study aimed to implement low-frequency forced oscillation technique (LFFOT) in neonatal total liquid ventilation (TLV) and to provide the first insight into respiratory impedance under this new modality of ventilation. Thirteen newborn lambs, weighing 2.5 + or - 0.

A regulator for pressure-controlled total-liquid ventilation.

Total-liquid ventilation (TLV) is an innovative experimental method of mechanical-assisted ventilation in which lungs are totally filled and then ventilated with a tidal volume of perfluorochemical liquid by using a dedicated liquid ventilator. Such a novel medical device must resemble other conventional ventilators: it must be able to conduct controlled-pressure ventilation. The objective was to design a robust controller to perform pressure-regulated expiratory flow and to implement it on our latest liquid-ventilator prototype (Inolivent-4).