BACKGROUND Positive expiratory pressure (PEP) and CPAP are used to enhance breathing parameters such as functional residual capacity (FRC) in patients. Studies comparing effects of PEP and CPAP on FRC are few and variable. One reason for this may be that sophisticated equipment, not suitable in the clinical setting, is required. Because total lung capacity (TLC) consists of inspiratory capacity...

BACKGROUND The Innocor device contains a highly sensitive photoacoustic gas analyser that has been used to perform multiple breath washout (MBW) measurements using very low concentrations of the tracer gas SF6. Use in smaller subjects has been restricted by the requirement for a gas analyser response time of <100 ms, in order to ensure accurate estimation of lung volumes at rapid ventilation ra...

BACKGROUND The respiratory mass spectrometer is the current gold-standard technique for performing multiple-breath inert gas washout (MBW), but is expensive and lacks portability. A number of alternative techniques have recently been described. OBJECTIVES We aimed to validate, using an in vitro lung model, an open-circuit MBW system that utilises a portable photoacoustic gas analyser, with su...

The lymph node vasculature is essential to immune function, but mechanisms regulating lymph node vascular maintenance and growth are not well understood. Vascular endothelial growth factor (VEGF) is an important mediator of lymph node endothelial cell proliferation in stimulated lymph nodes. It is expressed basally in lymph nodes and up-regulated upon lymph node stimulation, but the identity of...

Lung volumes in irreversible diffuse obstructive pulmonary syndromes (DOPS(I)) have been studied by using an analog of the lung that simulates an 18-breath nitrogen washout. The functional residual capacity (FRC), the dead space volume (Vd), the distribution of ventilation, as well as the pattern of lung emptying have been measured in normal subjects and those with obstructive syndromes. The Vd...

OBJECTIVE Color match between fiber-reinforced composite (FRC) restorations and teeth is an imperative factor in esthetic dentistry. The purpose of this study is to evaluate the influence of veneering composites and fibers on the color change of FRC restorations. MATERIALS AND METHODS Glass and polyethylene fibers were used to reinforce a direct microhybrid composite (Z250, 3M ESPE) and a mic...

Hydrostatic weighing (HW) was performed at both residual volume (RV) and functional residual capacity (FRC) to determine if underwater weighing at different lung volumes affected the measurement of body density. Subjects were 43 males, 18-25 yr. Subjects were submerged in the prone position, and the lung volume was measured by helium dilution at the time of the underwater weighing. Underwater w...

AIM This study evaluated in vitro microleakage of inlays made by direct or indirect techique with or without fiber reinforced composite (FRC) substructure. MATERIALS AND METHODS Standardized mesio-occlusal cavities were prepared and restored using direct-technique with composite resin only or FRC-composite resin, and indirect technique with laboratory composite only or FRC-laboratory composit...

Hyperinflation is the consequence of a dysbalance of static forces (determining the relaxation volume) and/or of the dynamic components. The relaxation volume is determined by an equilibrium between the elastic recoil of the lungs and of the chest walls. The dynamic components include the pattern of breathing, upper airway resistance and postinspiratory activity of inspiratory muscles. The resp...

The purpose of the present study was to evaluate the bond strength between a fiber-reinforced composite (FRC) and six luting agents (Panavia F 2.0, Linkmax MC, Chemiace II, Multibond, Super-Bond C&B, and Fuji I). A prosthodontic resin composite material (RC-control) and a luting agent containing no functional monomer (MT) were used as controls. Shear bond strengths between alumina-blasted FRC a...