Methods We used SMS to collect symptoms and peak flow (PEF) meter readings from children with asthma. Digital PEF meters enabled data download to confirm validity of PEF data sent by SMS. Parents responded to 5 SMS messages daily for 7 days during baseline and for 14 days during a cold. Parents provided written feedback about the SMS-based data collection at the beginning (Q1) and at the end (Q...

BACKGROUND Recent evidence suggests that the frequency response requirements for peak expiratory flow (PEF) meters are higher than was first thought and that the American Thoracic Society (ATS) waveforms to test PEF meters may not be adequate for the purpose. METHODS The dynamic response of mini-Wright (MW), Vitalograph (V), TruZone (TZ), MultiSpiro (MS) and pneumotachograph (PT) flow meters ...

The effect of thermal and pulsed electric field (PEF) processing on the shelf life of an orange juice-milk beverage (OJMB) was studied. The intensities of the treatments were selected to produce similar inactivation of pectin methyl esterase (PME), an enzyme responsible for the jellification and loss of fresh juice cloudiness. Physical properties (pH, degrees Brix, and color), microbial populat...

BACKGROUND Bronchial reactivity measurements are widely used in epidemiological studies to provide an objective marker of asthma. There are, however, several potential advantages of measuring peak expiratory flow (PEF) variability instead, particularly in large studies. PEF variability and bronchial reactivity were compared in a population sample to assess the relationships of the two measureme...

A group of selected enzymes were subjected to continuous pulsed electric field (PEF) treatments to evaluate the inactivation effect of PEF. For a treatment time of 126 s, 51.7% and 83.8% of pepsin was inactivated at 37.0 kV/cm and 41.8 kV/cm, respectively. Enzyme activity of polyphenol oxidase decreased 38.2% when treated at 33.6 kV/cm for 126 s. Enzyme activity decreased 18.1% and 4.0% for per...

Peak expiratory flow (PEF) and plasma concentrations of platelet factor 4 and beta thromboglobulin were measured before and after exercise in nine asthmatic patients and 12 non-asthmatic volunteers. Exercise was preceded by administration in random order of either placebo, salbutamol 200 micrograms, or sodium cromoglycate 2 mg from a pressurised inhaler. In control subjects there were minimal c...

Panel studies have found 1-3% increases in reports of acute respiratory symptoms associated with each 10 microg x m(-3) increase in ambient concentrations of particles with a 50% cut-off aerodynamic diameter of 10 microm (PM10). Statistically significant decrements in population mean peak expiratory flow (PEF) have also been observed but their magnitude is only about 0.1% for the same exposure....

STUDY OBJECTIVE To determine if peak expiratory flow (PEF) is higher using incorrect technique versus correct technique with five marketed peak flowmeters. DESIGN Randomized, nonblinded study. SETTING University pulmonary medicine clinic. PATIENTS Twenty adults with clinically stable asthma. INTERVENTIONS After inhaling 2 puffs of albuterol via a valved aerosol holding chamber (Aerocham...

Methods and results We compared survival in patients with HF-PEF with that in patients with HF-REF in a meta-analysis using individual patient data. Preserved EF was defined as an EF ≥ 50%. The 31 studies included 41 972 patients: 10 347 with HF-PEF and 31 625 with HF-REF. Compared with patients with HF-REF, those with HF-PEF were older (mean age 71 vs. 66 years), were more often women (50 vs. ...

STUDY OBJECTIVES To evaluate features of the peak expiratory flow (PEF) test protocol, and to characterize patterns of reproducibility in multiple PEF measurements. DESIGN Cross-sectional study. SETTING University population. PARTICIPANTS Two hundred twenty-three healthy adults. INTERVENTIONS Participants recorded five PEF measurements in each of five sessions per day for 1 week. MEAS...