Functional residual capacity measurements in healthy infants: ultrasonic flow meter versus a mass spectrometer.

Accurate, reproducible and portable bedside monitoring of lung volume could potentially facilitate the early recognition of both under and overinflation of the lungs in ventilated and nonventilated subjects. This study asked whether a prototype portable ultrasonic flow meter provided valid and reliable measurements of functional residual capacity (FRCUS) when compared to those obtained using a mass spectrometer (FRCMS) in nonventilated healthy infants. Paired, randomised measurements of FRCMS and FRCUS were obtained using the sulphur hexafluoride (SF6) multiple-breath washout technique in 23 healthy infants with a median (range) postnatal age of 34.

Development of lung function in early life: influence of birth weight in infants of nonsmokers.

This study aimed to compare lung growth and development during the first year of life in healthy term infants of low or appropriate birth weight for gestation. Paired measurements of forced expiratory volume in 0.4 second, FVC, and forced expiratory flow when 75% of FVC has been exhaled were obtained, using the raised volume technique, at about 7 weeks and 9 months of age in 80 infants (32 low and 48 appropriate birth weight for gestation) of white, nonsmoking mothers.

Respiratory physiotherapy vs. suction: the effects on respiratory function in ventilated infants and children.

Objective: To assess and compare the effects of physiotherapy and suction on expired tidal volume (V(TE)), respiratory compliance (C(rs)), resistance (R(rs)) and arterial blood gases.

Design: Randomised cross-over study comparing outcomes after both treatments on the same day.

Setting: Intensive tertiary care units, Great Ormond Street Hospital, London.

Human physiological responses to cold exposure.

Thermal energy is transferred within and between bodies via several avenues, but for most unprotected human cold exposures, particularly during immersion, convective heat loss dominates. Lower tissue temperatures stimulate thermoreceptors, and the resultant afferent flow elicits autonomic homoeostatic responses (thermogenesis and vasoconstriction) that regulate body temperature within a narrow range. The most powerful effector responses occur when both superficial and deep thermoreceptors are cooled simultaneously, but thermoeffector activation can also occur as a result of peripheral cooling alone.

The influence of physiotherapy and suction on respiratory deadspace in ventilated children.

Objective: To assess and compare the effects of respiratory physiotherapy and suction on deadspace volumes, carbon dioxide elimination (VCO(2)), end tidal CO(2) (ETCO(2)), and arterial partial pressure of carbon dioxide (PaCO(2)) in ventilated infants and children.

Design: Randomised crossover study. Participants received both treatments with a washout interval of more than 90 min.

Interactions between temperature and human leptin physiology in vivo and in vitro.

To investigate the possibility that environmental temperature may exert physiologically significant direct, local effects on subcutaneous adipose tissue temperatures, and its secretion of leptin, we exposed healthy males ( n=12) to repeated cold-water immersion (study 1), and also incubated surgically removed human subcutaneous adipose tissue samples ( n=7) at 27 degrees, 32 degrees and 37 degrees C (study 2). In vivo immersions were conducted over 15 days (60-90 min at 18 degrees C). Regional body temperatures and plasma leptin concentrations were measured before and during immersion.

Quality control for spirometry in preschool children with and without lung disease.

The reliability of spirometry is dependent on strict quality control. We examined whether quality control criteria recommended for adults could be applied to children aged 2-5 years. Forty-two children with cystic fibrosis and 37 healthy children attempted spirometry during their first visit to our laboratory.

Transition from estrogen therapy to raloxifene in postmenopausal women: effects on treatment satisfaction and the endometrium-a pilot study.

Objective: To compare the effects of transferring from low-dose, transdermal estrogen to raloxifene with a phase of alternate-day raloxifene therapy with or without low-dose transdermal estrogen on patient satisfaction, endometrial changes, and overall safety in healthy, postmenopausal women previously administered hormone therapy.

Design: Healthy postmenopausal women were randomized to one of two treatment groups: raloxifene + low-dose, transdermal estrogen (RLX+E) and raloxifene + placebo (RLX+P). The study consisted of four equal phases of 8 weeks each: Phase I (low-dose, transdermal estrogen, 25 microg/day), phase II (double-blind, alternate-day raloxifene 60 mg + low-dose, transdermal estrogen or placebo patch), phase III (alternate-day RLX 60 mg + placebo patch), and phase IV (raloxifene 60 mg/day + placebo patch).

Transition to raloxifene with and without low-dose estrogen therapy in postmenopausal women: effects on serum lipids and fibrinogen - a pilot study.

Objective: To compare the effects of transferring from low-dose transdermal estrogen to raloxifene (RLX), with a phase of alternate-day RLX therapy with or without low-dose transdermal estrogen, on serum lipids and fibrinogen in postmenopausal women previously administered estrogen plus progestogen therapy.

Methods: Sixty postmenopausal women (mean age 55 years) were randomized to one of two treatment groups: RLX + low-dose transdermal estrogen (RLX + E) or RLX + placebo. The study consisted of four 8-week phases: phase I (all subjects low-dose transdermal estrogen 25 microg/day), phase II (double-blind RLX 60 mg every 2nd day in combination with either low-dose transdermal estrogen or placebo), phase III (all subjects RLX 60 mg every 2nd day + placebo) and phase IV (all subjects RLX 60 mg/day + placebo).

Cold-water acclimation does not modify whole-body fluid regulation during subsequent cold-water immersion.

We investigated the impact of cold-water acclimation on whole-body fluid regulation using tracer-dilution methods to differentiate between the intracellular and extracellular fluid compartments. Seven euhydrated males [age 24.7 (8.

The evolution of airway function in early childhood following clinical diagnosis of cystic fibrosis.

This study aimed to investigate the evolution of airway function in infants newly diagnosed with cystic fibrosis (CF). FEV(0.5) was measured soon after diagnosis (median age of 28 weeks) and 6 months later in subjects with CF and on two occasions 6 months apart (median ages of 7.

Low birth weight for gestation and airway function in infancy: exploring the fetal origins hypothesis.

Background: Poor fetal growth has been associated with impaired airway function in adult life, but evidence linking birth weight and airway function in early childhood is sparse. We examined the hypothesis that low birth weight for gestation is associated with impaired airway function shortly after birth and that this is independent of impaired postnatal somatic growth.

Methods: Airway function was measured using the raised volume technique in healthy white infants of low (< or =10th centile) or appropriate (> or =20th centile) birth weight for gestation and was expressed as forced expiratory volume in 0.

Assessment of tidal breathing parameters in infants with cystic fibrosis.

Simple methods are needed to assess lung function in infants with cystic fibrosis (CF). This study determined the relationship between simple measurements obtained from tidal breathing with those from more complicated forced expiratory manoeuvres. Healthy infants and infants with CF were recruited from two maternity units and five specialist CF hospitals, respectively.

Humid heat acclimation does not elicit a preferential sweat redistribution toward the limbs.

We tested the hypothesis that local sweat rates would not display a systematic postadaptation redistribution toward the limbs after humid heat acclimation. Eleven nonadapted males were acclimated over 3 wk (16 exposures), cycling 90 min/day, 6 days/wk (40 degrees C, 60% relative humidity), using the controlled-hyperthermia acclimation technique, in which work rate was modified to achieve and maintain a target core temperature (38.5 degrees C).

The effect of parental smoking on lung function and development during infancy.

While the adverse effects of parental smoking on respiratory health during childhood are well recognized, its potential impact on early lung development is less clear. This review summarizes current evidence on the effect of parental smoking on lung function during infancy. It is difficult to separate the effects of pre- and postnatal exposure, since the majority of mothers who smoke in pregnancy (currently around 30% worldwide) continue to do so thereafter.

A novel LCAT mutation (Phe382-->Val) in a kindred with familial LCAT deficiency and defective apolipoprotein B-100.

We studied a four-generation family (17 subjects) with familial lecithin:cholesterol acyltransferase (LCAT) deficiency. A 30-year-old Caucasian male with corneal clouding and HDL cholesterol <0.1 mmol/l was a compound heterozygote for a novel mutation (Phe(382)-->Val), a previously reported mutation (Thr321-->Met) and a common variant (Thr208-->Ser) of the gene.

Effects of raloxifene hydrochloride on bone mineral density, bone metabolism and serum lipids in postmenopausal women: a randomized clinical trial in Beijing.

Objective: To determine the effects of raloxifene hydrochloride (RLX) on bone mineral density (BMD), bone metabolism markers and serum lipids in healthy postmenopausal women in Beijing.

Methods: A multicenter, randomized, double-blind, placebo-controlled study was conducted in a total of 204 healthy postmenopausal women (age 59.5 +/- 5.

Predicting oxygen uptake for men and women with moderate to severe chronic obstructive pulmonary disease.

Objective: To develop regression equations for estimating peak oxygen consumption (Vo(2)) for men and women with moderate to severe chronic obstructive pulmonary disease (COPD) from the 6-minute walk test (6MWT).

Design: Multivariate analysis of patient pulmonary function and exercise gas exchange indices to 2 outcomes for the 6MWT (distance ambulated, calculated work [6M(WORK)]).

Setting: A university hospital and clinics.

Peak physiologic responses to arm and leg ergometry in male and female patients with airflow obstruction.

Study Objective: To investigate differences in work capacity for the arms and legs in patients with moderate-to-severe COPD.

Design: Cross-sectional investigation.

Patients: One hundred twenty-four patients (90 men and 34 women) aged 45 to 81 years with moderate-to-very severe COPD.

Progressive decline in plethysmographic lung volumes in infants: physiology or technology?

During the last 30 years, there has been an unexplained trend toward declining values for plethysmographic assessments of lung volume at functional residual capacity (FRC) in infants. The aim of this study was to compare data collected from healthy infants using contemporary equipment with published reference data and to explore reasons for discrepancies. Lung volumes were measured in 32 healthy infants (age, 4-93 weeks; weight, 3.

[A randomised clinical trial to study the effects of raloxifene hydrochloride on bone mineral density, biochemical markers of bone metabolism and serum lipids in postmenopausal women].

Objective: To determine the effect of raloxifene hydrochloride (RLX) on bone mineral density (BMD), biochemical markers of bone metabolism and lipid metabolism in Chinese postmenopausal women.

Methods: This was a multicenter, randomized, double blind placebo controlled study in China with a total of 204 postmenopausal women [mean age (60 +/- 5) years (x +/- s) and weight (63 +/- 9) kg (x +/- s)] treated with either RLX 60 mg (n = 102) or placebo (n = 102) daily for 12 months. BMD, serum lipid and bone markers were determined before and after drug administration.

6-minute walk work for assessment of functional capacity in patients with COPD.

Unlabelled: The 6-min walk (6MW) test is commonly used to assess exercise capacity in patients with COPD and to track functional change resulting from disease progression or therapeutic intervention. Not surprisingly, distance covered has been the preferred outcome for this test. However, distance walked does not account for differences in body weight that are known to influence exercise capacity.