Outcomes of an early childhood obesity prevention program in a low-income community: a pilot, randomized trial.

BACKGROUND: Obesity is a major and worldwide health problem in children. OBJECTIVES: The Early Childhood Obesity Prevention Program is a multi-component, randomized, controlled trial of a pilot community-focused obesity prevention program for mother/newborn dyads. METHODS: Underserved, mother/newborn dyads were recruited to receive a standard home visitation program (Nurturing Families Network, NFN) or an enhanced program (NFN+) that incorporated behavioural change strategies (e.g., goal-setting, problem-solving) and focused on six obesity-associated behaviours (breastfeeding, juice/sugar-sweetened beverages, solids, infant sleep, TV/screen time and soothability) with linkages to community resources. Weight-for-length (WFL) z-score and maternal diet were secondary outcomes. RESULTS: Fifty-seven dyads were recruited and 47 fully eligible dyads were enrolled (NFN = 21, NFN+ = 26). Forty-one (87.2%) were assessed at 6 months and 34 (72.3%) at 12 months. Retention at 12 months was higher for NFN+ dyads (84.6% vs. 56.1%, p = 0.04). NFN+ mothers were more likely to continue breastfeeding at 6 and 12 months vs. NFN mothers (p = 0.03 and 0.003, respectively), and at 12 months, NFN+ infants had fewer nocturnal awakenings (p = 0.04). There were no differences in other primary outcome measures or in WFL z-score at 6 or 12 months. CONCLUSIONS: A multi-component behavioural intervention increased breastfeeding duration and decreased nocturnal awakenings in infants of low-income families.

Genome-wide association study of body mass index in 23 000 individuals with and without asthma.

BACKGROUND: Both asthma and obesity are complex disorders that are influenced by environmental and genetic factors. Shared genetic factors between asthma and obesity have been proposed to partly explain epidemiological findings of co-morbidity between these conditions. OBJECTIVE: To identify genetic variants that are associated with body mass index (BMI) in asthmatic children and adults, and to evaluate if there are differences between the genetics of BMI in asthmatics and healthy individuals. METHODS: In total, 19 studies contributed with genome-wide analysis study (GWAS) data from more than 23 000 individuals with predominantly European descent, of whom 8165 are asthmatics. RESULTS: We report associations between several DENND1B variants (P = 2.2 × 10(-7) for rs4915551) on chromosome 1q31 and BMI from a meta-analysis of GWAS data using 2691 asthmatic children (screening data). The top DENND1B single nucleotide polymorphisms(SNPs) were next evaluated in seven independent replication data sets comprising 2014 asthmatics, and rs4915551 was nominally replicated (P < 0.05) in two of the seven studies and of borderline significance in one (P = 0.059). However, strong evidence of effect heterogeneity was observed and overall, the association between rs4915551 and BMI was not significant in the total replication data set, P = 0.71. Using a random effects model, BMI was overall estimated to increase by 0.30 kg/m(2) (P = 0.01 for combined screening and replication data sets, N = 4705) per additional G allele of this DENND1BSNP. FTO was confirmed as an important gene for adult and childhood BMI regardless of asthma status. CONCLUSIONS AND CLINICAL RELEVANCE: DENND1B was recently identified as an asthma susceptibility gene in a GWAS on children, and here, we find evidence that DENND1B variants may also be associated with BMI in asthmatic children. However, the association was overall not replicated in the independent data sets and the heterogeneous effect of DENND1B points to complex associations with the studied diseases that deserve further study.

Provider adherence to a clinical practice guideline for acute asthma in a pediatric emergency department.

UNLABELLED: Critics of the use of clinical practice guidelines (CPGs) in an emergency department (ED) setting believe that they are too cumbersome and time-consuming, but to the best of the authors' knowledge, potential barriers to CPG adherence in the ED have not been prospectively evaluated. OBJECTIVES: To measure provider adherence to an ED CPG based on National Asthma Education and Prevention Program (NAEPP) recommendations, and to determine factors associated with provider nonadherence. METHODS: Prospective, cohort study of children aged 1-18 years with the diagnosis of an acute exacerbation of asthma who were seen in a pediatric ED and requiring admission, as well as a random selection of children discharged to home following pediatric ED care. The following adherence parameters were assessed: at least three nebulized albuterol treatments in the first hour; early steroid administration (after the first nebulizer treatment); clinical assessments using pulse oximetry and peak expiratory flow (PEF) (for children >6 years old); and use of a clinical score to assess acute illness severity (Asthma Severity Score). Nonadherence was defined as any deviation of the above parameters. RESULTS: Between July 1, 1998, and June 30, 1999, 369 patients were studied. Of these, 38% (139) were discharged to home, 38% (140) were admitted to the observation unit, and 24% (90) were admitted to the inpatient unit. Illness severities at initial presentation to the ED were: 24% (86) had mild exacerbations, 59% (212) had moderate exacerbations, and 17% (62) had severe exacerbations. Sixty-eight percent (95% CI = 63% to 73%) of the patients were managed with complete adherence to the CPG. Of the 32% with some form of nonadherence, most (63%) were children older than 6 years; in this group 64% (48/75) were nonadherent due to lack of PEF assessment. When PEF assessment was disregarded, an 83% (95% CI = 79% to 87%) adherence to the CPG was achieved. Other nonadherence factors included: lack of at least three nebulized albuterol treatments provided timely within the first hour (5%); delay in steroid administration (6%); lack of pulse oximeter use (0.5%); and failure to record clinical score to assess severity (1.1%). Patient age, illness severity (acute and chronic), first episode of wheezing, and high ED volume periods (evenings and weekends) did not worsen adherence. CONCLUSIONS: Clinical practice guidelines can be used successfully in the pediatric ED and provide a more efficient management and treatment approach to acute exacerbations of childhood asthma. With a systematic and concise CPG, barriers to adherence in a pediatric ED appear to be minimal, with the exception of using PEF in the routine ED assessment.

Diagnosing pediatric asthma: validating the Easy Breathing Survey.

OBJECTIVE: To determine the sensitivity, specificity, and predictive value of a simple, self-administered questionnaire for the diagnosis of asthma in children. STUDY DESIGN: A questionnaire specifically designed to assist primary care providers in making a diagnosis of asthma in children was developed and administered in 4 different primary care and subspecialty clinics, validated, and then used as part of an asthma management program called Easy Breathing. Asthma diagnoses were made according to recommended National Asthma Expert Panel Guidelines. RESULTS: Four questions on the survey were shown to be sensitive and specific for asthma. The sensitivity was greater for all levels (mild, moderate, and severe) of persistent asthma than for mild, intermittent asthma. A positive response to any 1 of the 4 questions was over 94% sensitive for asthma; a negative response to all 4 questions was 55% specific for ruling out asthma. CONCLUSIONS: Patient responses to 4 specific respiratory symptom questions can assist primary care providers in diagnosing asthma in children. Primary care providers serving pediatric populations at high risk for asthma should consider asking patients or their parents these 4 questions regarding asthma symptoms on a regular basis.

Practice of pediatric pulmonology: results of the Future of Pediatric Education Project (FOPE)

In 1996, the Future of Pediatric Education (FOPE) Project of the American Academy of Pediatrics (AAP) developed surveys to describe the nature of pediatric practices, recent trends in clinical practice, and anticipated workforce needs for both pediatric generalists and pediatric sub-specialists. A survey was specifically developed to describe the features of pediatric pulmonology as self-reported by pediatric pulmonologists. The survey was distributed to members of the AAP Pulmonology Section, the Pediatric Assembly of the American Thoracic Society, and certified pediatric pulmonologists recognized by the American Board of Pediatrics. Of the 535 respondents (67% of those invited to respond), the responses of 388 certified and 94 trained but not board-certified pulmonologists were included in the results. The characteristics of certified and non-certified respondents were the same for most survey questions. Clinical activities occupy 73 +/- 29% of professional time. Most pulmonologists work in urban, inner city, or suburban settings and 85% are affiliated with a medical school. One third are in private practice. As a group, research activities occupy less than 15% of their time. Most pediatric pulmonologists maintain a referral practice and use physician extenders to provide care. Patients with asthma and cystic fibrosis comprise 60-70% of patient volume. Both the volume and complexity of patients are increasing, as is competition for pediatric sub-specialty services. Pediatric pulmonary practices vary in size and in volume of patients that they manage in various settings. Forty percent of respondents identify allergists and other pediatric pulmonologists as sources of competition. Sixty-nine percent of respondents do not believe that there is a current need for additional pediatric pulmonologists in their respective communities. Only 15% of respondents plan to retire in the next decade.

Factor and subscale structure of a parental health locus of control instrument (parental health beliefs scales) for use in a mainland United States Puerto Rican community.

This study was undertaken to determine whether the subscale structure of an instrument used to measure parental health locus of control is a valid representation of the concept of locus of control in the Puerto Rican community. Ethnocultural differences in values and attitudes may create different conceptualizations of questionnaire items, which may impact on the subscale factor loadings for these items. Four hundred and twenty parents of Puerto Rican ethnicity living in a mainland inner city community in the United States completed the Parental Health Beliefs Scales (PHBS) instrument, which was developed to measure parental locus of control regarding their children's health. Results were subject to exploratory factor analysis. The resultant factor structure was then compared to other published factor structures by confirmatory factor analysis. Exploratory factor analysis results show a new five factor solution. Compared to two previously published factor structures for this instrument, the new five factor structure has a better goodness of fit for this Puerto Rican study sample. Through item analysis, we were able to refine the final structure into a four factor, 15 item instrument. We conclude that the new factor structure for the PHBS creates an instrument with subscales that reflect Puerto Rican cultural beliefs and values, especially as it pertains to locus of control issues (e.g. respect of professionals, collectivism, and the importance of fate). When working with ethnocultural minority groups, the health services researcher needs to be certain that the research instruments used are culturally appropriate and sensitive.

Byssinosis: role of polymer length on the effect of tannin on the airway beta-adrenergic receptor.

Tannin, isolated from cotton bracts and implicated in the pathogenesis of byssinosis, inhibits isoproterenol and forskolin-stimulated cAMP release from airway cells in part by decreasing cell surface beta-adrenergic receptor number and uncoupling the beta-adrenergic receptor from its stimulatory G-protein (Gs) and in part by inhibiting adenylyl cyclase activity. We have hypothesized that cotton tannin, because of its long polymer length, interacts with the hydrophobic binding pocket of the beta-adrenergic receptor and alters beta-adrenergic receptor binding and Gs coupling. In these studies, tannins of three different polymer lengths and molecular masses were isolated from cotton bracts using sequential Amicon ultrafiltration [molecular mass > 10, 000 (YM10 retentate), 1,000-10,000 (YM10 filtrate), and 1,000-5,000 Da (YM2 retentate)]. The YM10 retentate (25 microg/ml) decreased chloride secretion (Jnet = 1.11 +/- 0.28 (control) to 0.59 +/- 0.18 microEq/cm2.h, p < 0.05, n = 6), decreased cell surface beta-adrenergic receptor number (18.0 +/- 1.8 (control) to 10.6 +/- 0.9 fmol/mg protein, p < 0.02, n = 4), and inhibited forskolin-stimulated cAMP release (5,254 +/- 1,290 (control) to 2, 968 +/- 620 pmol/mg protein, p < 0.01, n = 8). In contrast, neither the YM10 filtrate nor the YM2 retentate had any effect on net chloride secretion, beta-adrenergic cell surface receptor number, or forskolin-stimulated cAMP release. We conclude that polymer length is essential for the effect of tannin on the beta-adrenergic receptor and on adenylyl cyclase.

Tannin inhibits the cAMP-beta-adrenergic receptor pathway in bovine tracheal epithelium.

Tannin, isolated from cotton bracts, inhibits chloride secretion in airway epithelium. In bovine tracheal epithelial cells, tannin (25 micrograms/ml) blunted isoproterenol (Iso)-stimulated adenosine 3',5'-cyclic monophosphate (cAMP) accumulation. Inhibition was time and dose dependent, with 52 +/- 5% (mean +/- SE, n = 6) inhibition at 60 min and 82 +/- 9% (n = 3) inhibition at 8 h. Inhibition was reversible starting at 4 h. Low-molecular-mass tannin (1,000-5,000 Da) had no effect on Iso-stimulated cAMP accumulation, whereas N-acetylcysteine, which interacts with cysteine residues, blocked the effects of tannin on Iso-stimulated cAMP accumulation. Tannin exposure (25 micrograms/ml for 30 min) had no effect on the dissociation constant (Kd) for [3H]dihydroalprenolol (DHA) (0.41 +/- 0.03 nM, n = 3) but decreased maximal binding from 252 +/- 32 to 162 +/- 36 fmol/mg protein. Using single-point analysis and [3H]CGP-12177, we determined that tannin (25 micrograms/ml for 4 h) decreased surface beta-adrenergic receptor density from 26.4 +/- 4.3 (n = 12) to 11.9 +/- 3.0 fmol/mg protein and that the decrease was dose dependent. Agonist binding affinity by Iso displacement of DHA demonstrated a two-site model (Kd values = 27 +/- 9 and 2,700 +/- 600 nM) and a ratio of high- to low-affinity receptors of 1:1. Tannin (25 micrograms/ml) steepened the curve and shifted it to the right, as did Gpp(NH)p. Gpp(NH)p had no further effect on the shape or position of the displacement curve in the presence of tannin. In contrast, when polymer length was decreased by oxidation, tannin had no effect on the DHA displacement curve. These data demonstrate that tannin reversibly desensitizes bovine tracheal epithelial cells to Iso, decreases beta-adrenergic receptor density, and uncouples the receptor from its stimulatory G protein. These data also suggest that the polymer length of tannin and its interaction with cysteine residues are important for these effects. These studies provide additional evidence for the role of tannin in the occupational lung disease byssinosis.

Tannin stimulates arachidonic acid release from bovine tracheal epithelial cells.

Condensed tannin, isolated from cotton bracts extract (CBE), increases arachidonic acid (AA) release from rabbit alveolar macrophages and inhibits its subsequent reacylation. We determined whether tannin from CBE had any effect upon AA release in bovine tracheal epithelial cells (BTE). [14C] AA release was measured at timed intervals after addition of various concentrations of tannin to BTE cells grown to confluence in the presence of [14C] AA. Tannin caused a time- and dose-dependent release of AA from airway cells, with a maximum release occurring at 1 min in the presence of 100 micrograms/ml of tannin, and was confirmed by high-pressure liquid chromatography. The pattern of release was similar to that observed with bradykinin (2 x 10(-6) M). AA release by tannin was partially inhibited by indomethacin (10(-5) M) but not by 5,8,11,14-eicosatetraynoic acid (ETYA; 10(-5) M. Both of these drugs were effective in inhibiting bradykinin-induced AA release. In addition, AA release was not inhibited by cycloheximide. Endotoxin at 100 pg/ml and higher also caused a time-dependent release of AA that was not inhibitable by indomethacin or ETYA. Tannin-induced AA release was inhibited by pretreatment with pertussis toxin but not by neomycin, an inhibitor of phospholipase C (PLC). Neither pertussis toxin nor neomycin had any effect upon endotoxin-induced AA release. In other experiments, neither tannin nor endotoxin had any effect on [14C]AA uptake by BTE. These data demonstrate that tannin at low concentrations and endotoxin at high concentrations increase AA release by BTE cells. The AA release by tannin is partially metabolized by the cyclooxygenase pathway. We hypothesize that tannin-induced AA release is not mediated by PLC but may be mediated by other phospholipases, including PLA2.

Ethnomedical (folk) remedies for childhood asthma in a mainland Puerto Rican community.

BACKGROUND: Childhood asthma is the most common chronic illness of childhood. The highest prevalence of childhood asthma in the United States occurs in the Puerto Rican community, and there are many traditional beliefs and practices regarding asthma that coexist with biomedical therapies. OBJECTIVES: To describe the ethnomedical treatment practices for childhood asthma in one mainland United States Puerto Rican community and to determine whether any of these practices are effective or potentially harmful. METHOD: Home interview with caretakers of 118 Puerto Rican children with asthma who seek care at two community health clinics in an inner city in the eastern United States. RESULTS: Common home-based ethnomedical practices include attempts to maintain physical and emotional balance and harmony, religious practices, and ethnobotanical and other therapies. Potentially harmful practices are uncommon, and other remedies are only harmful if not taken as directed. Many remedies are not effective from a biomedical standpoint (ie, bronchodilation or antiinflammation), but if analyzed within the ethnomedical explanatory model--which includes the belief that expulsion of mucus and phlegm from the body is beneficial for the treatment of asthma--these remedies bring about the desired effect and are therefore considered effective to the user. CONCLUSIONS: Ethnomedical therapies for asthma in the mainland Puerto Rican community are well known and commonly used. Most practices are not idiosyncratic but fit within a coherent ethnocultural belief system. The health care practitioner can lower the risk for potentially toxic effects of some treatments by discussing these practices with patients and families. Some ethnomedical practices are not discordant with biomedical therapy. Incorporation of these practices into the biomedical plan may help to fit the biomedical therapy into the lifestyle of the patient.

Tannin inhibits adenylate cyclase in airway epithelial cells.

Tannin, isolated from cotton bracts extract and implicated in the pathogenesis of byssinosis, inhibits adenosine 3',5'-cyclic monophosphate (cAMP) production and Cl- secretion in bovine airway epithelial cells in part by inhibiting adrenergic receptor binding. The purpose of this study was to determine whether tannin affected other parts of the adrenergic-cAMP signal transduction pathway by examining the effect of tannin on guanosine 5'-triphosphate (GTP)-regulatory pathways (G proteins) and on adenylate cyclase activity. cAMP production in confluent airway epithelial cells was measured in the presence of cholera toxin (100 micrograms/ml), an activator of GS proteins, and forskolin (0.1-1,000 microM), a direct activator of adenylate cyclase. Cholera toxin stimulated cAMP production; this response, however, was inhibited in cells pretreated with 50 micrograms/ml tannin. Forskolin (100 microM) stimulated cAMP production 13-fold above baseline values. Tannin pretreatment inhibited the stimulatory effect of forskolin on cAMP release in a dose-dependent manner with a tannin concentration causing 50% inhibition of 7.5 micrograms/ml. The stimulatory effect of forskolin on cAMP release was completely inhibited in cells pretreated with 50 micrograms/ml tannin. The inhibition was reversible 3 h after removal of tannin from the solution. Tannin also inhibited forskolin-stimulated adenylate cyclase activity in a dose-dependent, noncompetitive manner. We conclude that forskolin and cholera toxin stimulate cAMP production in airway epithelial cells and that tannin inhibits the production of cAMP in airway epithelial cells by a direct effect on adenylate cyclase activity.

Pulmonary function abnormalities in Prader-Willi syndrome.

OBJECTIVE: To determine whether individuals with Prader-Willi syndrome (PWS) have abnormalities in pulmonary function as a result of thoracic muscle weakness. DESIGN: Testing of spirometry, flow-volume curves, lung volumes, and static respiratory pressures was performed in patients with PWS who are followed at the University of Connecticut. All tests were performed in triplicate on two or more occasions. Only reproducible tests were accepted. Established normative data were applied for all test results. RESULTS: A total of 18 male subjects (age, 17.9 +/- 10.2 years (mean +/- SD); range, 5-39 years) and 17 female subjects (age, 23.5 +/- 13.0 years; range, 5-54 years) completed the tests. Forced vital capacity and forced expiratory volume in 1 second were reduced; the forced expiratory volume in 1 second/forced vital capacity ratio was normal, total lung capacity was in the low normal range, and residual volume was elevated. Maximum inspiratory (PImax) and expiratory (PEmax) pressures were markedly reduced in 32 subjects tested. Fifteen subjects had PEmax values and 20 subjects had PImax values < 60 cm H2O, respectively. There was a linear correlation between forced expiratory volume in 1 second and both PImax and PEmax (r = 0.71; r = 0.62, respectively), and between forced vital capacity and both PEmax and PImax (r = 0.62 and r = 0.74, respectively). There was an inverse relationship between both PImax and PEmax, and residual volume (r = 0.47 and r = 0.72, respectively). CONCLUSION: Children and adults with PWS have restrictive ventilatory impairment primarily as a result of respiratory muscle weakness. Efforts to improve thoracic muscle strength may be useful in improving pulmonary function in individuals with PWS.

Tannin inhibition of protein kinase C in airway epithelium.

Tannin, a polydisperse polyphenol extracted from cotton bracts (CBE), has been implicated in the pathogenesis of byssinosis, a lung disease of mill workers. CBE tannin inhibits chloride secretion in airway epithelial cells by means of an unknown mechanism(s). Activation of protein kinase C (PKC) by PMA (phorbol 12-myristate 13-acetate) in airway cells increases chloride secretion. The effect of tannin on this PKC pathway was examined, using canine tracheal epithelium mounted in Ussing chambers. PMA addition (10 nM) to the mucosal bath resulted in a 0.36 +/- 0.07 microEq/cm2.h (mean +/- SEM, n = 20) increase in short-circuit current (Isc) and a 0.38 +/- 0.17 microEq/cm2.h increase in net chloride secretion (Jnet). The inactive 4 alpha-phorbol had no effect. Tannin addition to the mucosal bath produced a dose-dependent decrease in Isc and Jnet. In tissues pretreated with 2-50 micrograms/ml tannin, and subsequently stimulated with PMA, tannin inhibited PMA stimulation of chloride secretion beginning at a tannin concentration of 10 micrograms/ml (0.09 +/- 0.05 microEq/cm2.h [n = 10] increase in Isc and 0.08 +/- 0.03 microEq/cm2.h increase in Jnet with PMA after tannin pretreatment). At 50 micrograms/ml tannin, the stimulatory effect of PMA was completely abolished. The known PKC inhibitor, H-7 (20 microM), inhibited PMA stimulation, while chelerythrine (2 microM) had not effect on PMA-stimulated Isc and Jnet, and calphostin C was toxic to the airway epithelium. In membrane fragments, 2.5 micrograms/ml tannin inhibited the rate of histone III phosphorylation by PMA from 32.1 +/- 4.4 nmol/mg protein per min to 20.1 +/- 2.7 nmol/mg protein per min (n = 7). In bovine airway cells, tannin pretreatment (2.5 micrograms/ml) decreased the cytosolic activity of PKC but had no effect on PKC translocation to the membrane. We conclude that tannin inhibits chloride secretion in airway epithelial cells in part by inhibiting PKC.

Tannin inhibits cAMP pathways in bovine airway epithelium.

Tannin, isolated from aqueous extracts of cotton bracts, inhibits chloride secretion in airway epithelial cells. The effect of tannin on the epinephrine- and bradykinin-stimulated rise in intracellular free calcium and cyclic adenosine monophosphate (cAMP) was examined using bovine tracheal epithelial cells in suspension and culture. Basal intracellular calcium levels were 33 +/- 11 nM (mean +/- SEM, n = 54) and increased 13- to 15-fold after addition of epinephrine (10(-6) M) or bradykinin (2 x 10(-6) M). Tannin pretreatment blunted the subsequent response to epinephrine beginning at a tannin concentration of 10 micrograms/ml. Pretreatment with 100 micrograms/ml tannin completely inhibited the rise in intracellular free calcium in response to epinephrine but had no effect on the calcium response to bradykinin. In the absence of tannin, both bradykinin and epinephrine increased intracellular levels of cAMP. At a tannin concentration of 10 micrograms/ml, tannin inhibited the rise in intracellular cAMP in cells stimulated with either epinephrine or bradykinin but had no effect on bradykinin-stimulated prostaglandin E2 release. Tannin alone (10 micrograms/ml) increased prostaglandin E2 release. In other studies, tannin inhibited epinephrine binding to airway epithelial cells in a dose-dependent manner. R(o) decreased from 948 +/- 69 fmol/mg protein under control conditions (n = 4) to 587 +/- 131 fmol/mg protein in the presence of 25 micrograms/ml tannin (n = 3). Tannin had no effect upon the Kd for epinephrine binding (132 +/- 12 pM). Tannin had no effect on bradykinin binding to airway epithelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Duramycin increases intracellular calcium in airway epithelium.

Duramycin increases short-circuit current (Isc) and net Cl- secretion in tracheal epithelium. We measured the intracellular free calcium ([Ca2+]i) response to duramycin using Indo-1 and bovine and canine tracheal cell suspensions, and the effect of an intracellular calcium chelator, BAPTA, and the protein kinase C inhibitor, staurosporine, on the Isc and [Ca2+]i response to duramycin. [Ca2+]i increased in a dose-dependent manner from basal levels of 34 +/- 5 to 949 +/- 136 nM at 5 x 10(-6) M duramycin. Both BAPTA (50 microM) and staurosporine (5-50 nM) pretreatment blunted the increase in Isc and net Cl- secretion produced by duramycin. BAPTA also blunted the rise in [Ca2+]i produced by duramycin (5 x 10(-6) M) in the presence of extracellular calcium (499 +/- 122 nM). In the absence of extracellular calcium, the duramycin-induced (5 x 10(-6) M) rise in [Ca2+]i was blunted from 949 +/- 136 nM (stimulation in the presence of Ca2+) to 621 +/- 122 nM, and was further decreased in the presence of BAPTA to 197 +/- 42 nM. In contrast, staurosporine (50 nM) pretreatment had no effect on the rise in [Ca2+]i produced by duramycin (basal 90 +/- 27 to 861 +/- 110 nM at 5 x 10(-6) M). Duramycin had no effect on [Ca2+]i in human neutrophils. These data demonstrate that duramycin releases calcium from intracellular stores and stimulates the influx of calcium in airway epithelial cells. These data also demonstrate that, in the presence of protein kinase C pathway blockade, an increase in intracellular free calcium is not sufficient for chloride secretion; thus, duramycin-stimulated chloride secretion may depend upon protein kinase C.

Congenital cystic adenomatoid malformation.

Congenital cystic adenomatoid malformation is an uncommon congenital anomaly. We present four additional children with CCAM and review the literature. Two of these children had unusual manifestations of CCAM--one presented with a "cavitary lesion" while the other is suspected of having bilateral disease.