The effect of exposure to a single vowel on talker normalization for vowels.

The current work investigated the role of single vowels in talker normalization. Following initial training to identify six talkers from the isolated vowel /i/, participants were asked to identify vowels in three different conditions. In the blocked-talker conditions, the vowels were blocked by talker. In the mixed-talker conditions, vowels from all six talkers were presented in random order. The precursor mixed-talker conditions were identical to the mixed-talker conditions except that participants were provided with either a sample vowel or just the written name of a talker before target-vowel presentation. In experiment 1, the precursor vowel was always spoken by the same talker as the target vowel. Identification accuracy did not differ significantly for the blocked and precursor mixed-talker conditions and both were better than the pure mixed-talker condition. In experiment 2, half of the trials had a precursor spoken by the same talker as the target and half had a different talker. For the same-talker precursor condition, the results replicated those in experiment 1. In the different-talker precursor, no benefit was observed relative to the pure-mixed condition. In experiment 3, only the written name was presented as a precursor and no benefits were observed relative to the pure-mixed condition.

Subglottal resonances of adult male and female native speakers of American English.

This paper presents a large-scale study of subglottal resonances (SGRs) (the resonant frequencies of the tracheo-bronchial tree) and their relations to various acoustical and physiological characteristics of speakers. The paper presents data from a corpus of simultaneous microphone and accelerometer recordings of consonant-vowel-consonant (CVC) words embedded in a carrier phrase spoken by 25 male and 25 female native speakers of American English ranging in age from 18 to 24 yr. The corpus contains 17,500 utterances of 14 American English monophthongs, diphthongs, and the rhotic approximant [[inverted r]] in various CVC contexts. Only monophthongs are analyzed in this paper. Speaker height and age were also recorded. Findings include (1) normative data on the frequency distribution of SGRs for young adults, (2) the dependence of SGRs on height, (3) the lack of a correlation between SGRs and formants or the fundamental frequency, (4) a poor correlation of the first SGR with the second and third SGRs but a strong correlation between the second and third SGRs, and (5) a significant effect of vowel category on SGR frequencies, although this effect is smaller than the measurement standard deviations and therefore negligible for practical purposes.

Once daily insulin detemir in cystic fibrosis with insulin deficiency.

The aim of this study was to determine if once daily insulin detemir reverses decline in weight and lung function in patients with cystic fibrosis (CF). 12 patients with early insulin deficiency and six with CF related diabetes (aged 7.2-18.1 years) were treated for a median of 0.8 years. Changes in weight and lung function following treatment were compared to pretreatment changes. Before treatment, the change in weight SD score (ΔWtSDS), percentage of predicted forced expiratory volume in 1 s (Δ%FEV(1)) and percentage of predicted forced vital capacity (Δ%FVC) declined in the whole study population (-0.45±0.38, -7.9±12.8%, -5.8±14.3%) and in the subgroup with early insulin deficiency (-0.41±0.43, -9.8±9.3%, -6.8±10.3%). Following treatment with insulin ΔWtSDS, Δ%FEV(1) and Δ%FVC significantly improved in the whole study population (+0.18±0.29 SDS, p=0.0001; +3.7±10.6%, p=0.007; +5.2±12.7%, p=0.013) and in patients with early insulin deficiency (+0.22±0.31 SDS, p=0.003; +5.3±11.5%, p=0.004; +5.8±13.4%, p=0.024). Randomised controlled trials are now needed.

Resonances and wave propagation velocity in the subglottal airways.

Previous studies of subglottal resonances have reported findings based on relatively few subjects, and the relations between these resonances, subglottal anatomy, and models of subglottal acoustics are not well understood. In this study, accelerometer signals of subglottal acoustics recorded during sustained [a:] vowels of 50 adult native speakers (25 males, 25 females) of American English were analyzed. The study confirms that a simple uniform tube model of subglottal airways, closed at the glottis and open at the inferior end, is appropriate for describing subglottal resonances. The main findings of the study are (1) whereas the walls may be considered rigid in the frequency range of Sg2 and Sg3, they are yielding and resonant in the frequency range of Sg1, with a resulting ~4/3 increase in wave propagation velocity and, consequently, in the frequency of Sg1; (2) the "acoustic length" of the equivalent uniform tube varies between 18 and 23.5 cm, and is approximately equal to the height of the speaker divided by an empirically determined scaling factor; (3) trachea length can also be predicted by dividing height by another empirically determined scaling factor; and (4) differences between the subglottal resonances of males and females can be accounted for by height-related differences.

Early glucose abnormalities in cystic fibrosis are preceded by poor weight gain.

OBJECTIVE: Progressive beta-cell loss causes catabolism in cystic fibrosis. Existing diagnostic criteria for diabetes were based on microvascular complications rather than on cystic fibrosis-specific outcomes. We aimed to relate glycemic status in cystic fibrosis to weight and lung function changes. RESEARCH DESIGN AND METHODS: We determined peak blood glucose (BG(max)) during oral glucose tolerance tests (OGTTs) with samples every 30 min for 33 consecutive children (aged 10.2-18 years). Twenty-five also agreed to undergo continuous glucose monitoring (CGM) (Medtronic). Outcome measures were change in weight standard deviation score (wtSDS), percent forced expiratory volume in 1 s (%FEV1), and percent forced vital capacity (%FVC) in the year preceding the OGTT. RESULTS: Declining wtSDS and %FVC were associated with higher BG(max) (both P = 0.02) and with CGM time >7.8 mmol/l (P = 0.006 and P = 0.02, respectively) but not with BG(120 min). A decline in %FEV1 was related to CGM time >7.8 mmol/l (P = 0.02). Using receiver operating characteristic (ROC) analysis to determine optimal glycemic cutoffs, CGM time above 7.8 mmol/l > or =4.5% detected declining wtSDS with 89% sensitivity and 86% specificity (area under the ROC curve 0.89, P = 0.003). BG(max) > or =8.2 mmol/l gave 87% sensitivity and 70% specificity (0.76, P = 0.02). BG(120 min) did not detect declining wtSDS (0.59, P = 0.41). After exclusion of two patients with BG(120 min) > or =11.1 mmol/l, the decline in wtSDS was worse if BG(max) was > or =8.2 mmol/l (-0.3 +/- 0.4 vs. 0.0 +/- 0.4 for BG(max) <8.2 mmol/l, P = 0.04) or if CGM time above 7.8 mmol/l was > or =4.5% (-0.3 +/- 0.4 vs. 0.1 +/- 0.2 for time <4.5%, P = 0.01). CONCLUSIONS: BG(max) > or =8.2 mmol/l on an OGTT and CGM time above 7.8 mmol/l > or =4.5% are associated with declining wtSDS and lung function in the preceding 12 months.

Mirth-triggered asthma: is laughter really the best medicine?

Mirthful emotions such as laughter and excitement are unrecognized but perhaps important triggers of asthma. Our study aimed to explore the prevalence, mechanisms, and associations of mirth-triggered asthma (MTA) in children. Our MTA prevalence questionnaire was given to 285 children who presented to the Emergency Department of Sydney Children's Hospital (SCH) with an acute episode of asthma. Our MTA profile questionnaire study was a cross-sectional study of 541 children with asthma. The parents completed a questionnaire regarding their child's asthma. In our laughter diary study, diary cards were given to the parents of 21 children with asthma. The diary required details regarding the mirthful stimulus, symptoms of asthma, and recording of peak expiratory flow (PEF) measurements. Of the selected cohort, 31.9% had mirth-triggered asthma. In the cross-sectional study, mirth-triggered asthma was more common: with increasing age (P = 0.02); in those who in the last 3 months had taken more doses of salbutamol (P = 0.005), and who had more wheeze, nocturnal symptoms, and early morning symptoms (P < 0.0005); and in those who reported exercise-induced asthma (P < 0.0005). Laughter was more commonly reported as a trigger than excitement; cough was the most prominent symptom; and symptoms mostly occurred within 2 min of the mirthful stimulus. In the laughter diary study, 59 of 130 recorded events described symptoms of asthma. Mirth while watching a film led to PEF of 73% of baseline, compared with 81% for mirth with exertional play, and 95% for mirth with nonexertional play (P = 0.01). Mirth-triggered asthma is common, and is an indicator of suboptimal asthma control.

Asthma exacerbations in children associated with rhinovirus but not human metapneumovirus infection.

Children with asthma were studied during the Southern hemisphere winter and summer of 2001-2002. Human rhinovirus (hRV) was significantly associated (P=.0001) with asthma exacerbations in winter and spring/summer, but not in intervening asymptomatic periods. Although hRV was also found in children with upper respiratory tract infection (URTI) who underwent sampling at the same time, it was present in significantly higher numbers of children with symptomatic asthma (P<.0001). Human metapneumovirus was also found in small numbers of children with URTI, but significantly less frequently in children with asthma.

Relationship between sputum inflammatory markers, lung function, and lung pathology on high-resolution computed tomography in children with cystic fibrosis.

High-resolution computed tomography (HRCT) is a sensitive technique for early visualisation and location of cystic fibrosis (CF) bronchopathology, and has been shown to detect acute reversible and chronic changes. It would be expected to correlate with markers of the underlying pathological processes, such as sputum cytokines and cytology, as well as with pulmonary function tests (PFTs). Our aim was to study the relationship between PFTs, sputum cytology, and sputum cytokine interleukin-8 (IL-8) and HRCT in CF patients. Prospective standardized collection of sputum samples was performed at the time of routine annual high-resolution CT scans. Forced expired volume in 1 sec (FEV(1)) and forced vital capacity (FVC) were recorded. Sputum processing was selective, with dispersal by the three-enzyme technique. IL-8 measurements were by kit assay. HRCT scans were scored by a pediatric radiologist, blinded to clinical condition, using a modified Bhalla score.Forty-three CT scans were performed on 34 children with CF between March 1998 and April 2000. Mean age was 12.3 years (range, 6-21 years), FEV(1) (% predicted) was 67% (range, 23-120%), and mean modified Bhalla score was 11.2 (range, 0-22). Sputum IL-8 concentration (mean, 86; range, 4-150 ng/mL) and total cell count (mean, 31.9 x 10(6)/mL; range, 21.8-42.0 x 10(6)/mL) were high. FEV(1) and FVC correlated with modified Bhalla score (r = -0.66, P < 0.0001 for both), and most individual components of the score, especially mosaic perfusion (r = -0.64, r = -0.61 respectively, P < 0.0001) and extent of bronchiectasis (r = -0.61, P < 0.0001 for both). The combination of these two predicted 58% of the variability in FEV(1) on analysis of variance (P < 0.0001). Sputum total cell count correlated weakly with modified Bhalla score (r = 0.38, P < 0.05) and with FEV(1) and FVC (r = -0.36, P < 0.05; and r = -0.46, P < 0.01). Differential cell counts, cell viability, and IL-8 did not correlate with modified Bhalla scores, or with reversible components such as mucus plugging, centrilobular nodules, or peribronchial thickening. In conclusion, pathological changes on HRCT correlated with lung function but not with sputum markers of inflammation.

Inflammation, infection, and pulmonary function in infants and young children with cystic fibrosis.

Our aim was to study the effect of lower airway infection on clinical parameters, pulmonary function tests, and inflammation in clinically stable infants and young children with cystic fibrosis (CF). To accomplish this goal, a prospective cohort of screened CF patients under 4 years of age were studied, using elective anesthesia and intubation for: passive respiratory mechanics (single breath occlusion passive deflation) and lung volumes (nitrogen washout), under neuromuscular blockade; and bronchoalveolar lavage (BAL) of 3 main bronchi for cytology, cytokine interleukin (IL)-8, and quantitative microbiology. There were 22 children studied, with a mean age of 23.2 months (6.7-44 months). A greater relative risk of lower airway pathogens was associated with prior respiratory admission (3.60, 95% confidence interval [CI] 2.87-4.51), history of asthma (1.75, 95% CI 1.52-2.03), and chronic symptoms (1.50, 95% CI 1.23-1.83), especially wheeze (1.88, 95% CI 1.61-2.19). Lower respiratory pathogens (> or = 10 cfu/ml BAL) were found in 14 out of 22, and greater than 10(5) cfu/ml in 8 out of 22 subjects. The level of pathogens in BAL (log10 cfu/ml) explained 78% of the variability in percent neutrophils and 34% of the variability in IL-8 levels. Pathogen level also correlated with pulmonary function tests of specific respiratory system compliance (r -0.49, p = 0.02) and functional residual capacity over total lung capacity (r 0.49, p = 0.03). We conclude that the presence of pathogens in the lower airways correlated with levels of inflammation, respiratory system compliance, and degree of air trapping.