Differential modulation of transforming growth factor-beta by betamethasone-17- valerate and isotretinoin: corticosteroid decreases and isotretinoin increases the level of transforming growth factor-beta in suction blister fluid.

Retinoids and glucocorticoids are known to have a potential to modulate the expression of transforming growth factor-beta (TGF-beta). We investigated the effect of oral isotretinoin (13-cis-retinoic acid) on the expression of two distinct isoforms of TGF-beta, TGF-beta1 and TGF-beta2, in suction blister fluid and serum in acne patients. We also investigated the effect of topical glucocorticoid (betamethasone-17-valerate) and age on suction blister fluid TGF-beta1 in healthy volunteers. Six weeks of isotretinoin treatment caused a statistically significant 19% increase in suction blister fluid TGF-beta1. The suction blister fluid TGF-beta2 level remained below the sensitivity level of the immunoassay in many cases. Isotretinoin did not affect the serum TGF-beta1 or TGF-beta2 level. Betamethasone-17-valerate pretreatment for 3 days twice a day caused a statistically significant 17% decrease in suction blister fluid TGF-beta1. The active form of TGF-beta1 represented 5% of the total TGF-beta1 in suction blister fluid. Our diffusion calculations suggest that all TGF-beta1 and TGF-beta2 detected in suction blister fluid have diffused from systemic circulation. The increase in suction blister fluid TGF-beta1 after isotretinoin treatment seems to be of local origin, while the decrease in suction blister fluid TGF-beta1 after glucocorticoid pretreatment seems to be due to glucocorticoid-induced vasoconstriction resulting in decreased diffusion of TGF-beta1 from the circulation. Modulation of local interstitial fluid TGF-beta1 concentration may be one mechanism by which isotretinoin and glucocorticoids mediate their effects in skin.

Low colostral IgA associated with cow's milk allergy.

During a nutritional study of 198 infants, seven became allergic to cow's milk. The seven infants showed acute cutaneous manifestations during cow's milk challenge tests in hospital and six had increased levels of IgE cow's milk-specific antibodies. Neither in the development of the levels of immunoglobulins G, A and M, nor in that of the cow's milk-specific antibodies of these isotypes did these seven patients differ from the remaining infants. Beta-lactoglobulin content and levels of cow's milk-, and beta-lactoglobulin-specific antibodies and of immunoglobulins A, G and M were measured in samples of colostrum and milk from the mothers of the seven infants with cow's milk allergy and from a comparison group (non-atopic mothers of non-atopic infants). The milk of the mothers whose infants became allergic to cow's milk contained less IgA through the lactation: 95% confidence intervals of the groups did not overlap. The difference was most marked in the colostrum. All other measurements were similar in the two groups. This suggests that an infant is more likely to develop cow's milk allergy if the mother's colostrum had a low total IgA content.

Alpha-actinin and myosin light chains in congenital nemaline myopathy.

The muscle fibers of patients with congenital nemaline myopathy contain nemaline bodies, of which alpha-actinin is a major constituent. In some cases, deficiencies of fast myosin light chains have been reported. We performed 1-dimensional polyacrylamide sodium dodecyl sulfate gradient gel electrophoresis of muscle proteins from 13 patients with congenital nemaline myopathy and 10 controls to examine the alpha-actinin and the distribution of myosin light chains in congenital nemaline myopathy. At 95 kd (corresponding to alpha-actinin), 4 patients and all controls had 1 band, 2 patients did not have any bands, and 7 had bands that were clearly weaker than those of the controls. Because alpha-actinin is present in the nemaline bodies of congenital nemaline myopathy muscle, only the deficiency of this protein must be apparent. No apparent differences in fast myosin light-chain distribution could be documented between patients and controls; no correlation was observed between muscle fiber type and light-chain distribution. The results suggest that alpha-actinin is abnormal in congenital nemaline myopathy.

Surfactant proteins in the diagnosis of fetal lung maturity. II. The 35 kd protein and phospholipids in complicated pregnancy.

The major surfactant protein with a molecular weight of 35 kd and also saturated phosphatidylcholine and phosphatidylglycerol were analyzed in specimens of amniotic fluid; 68 were from cases of maternal diabetes, 41 from preeclampsia or maternal hypertension, 26 from premature rupture of the fetal membranes, and 45 from normal pregnancies. The relationship between the individual surfactant components was studied after covariance adjustment for the length of gestation. In severe early-onset preeclampsia, the 35 kd surfactant protein/saturated phosphatidylcholine ratio was significantly higher than in the other pregnancies. In diabetic pregnancies (classes B to D without preeclampsia), the phosphatidylglycerol/saturated phosphatidylcholine ratio was lower than in the other pregnancies. Isolated surfactant complex showed similar abnormalities. In severe early-onset preeclampsia and insulin-dependent diabetes without vascular disease, the phosphatidylglycerol/saturated phosphatidylcholine ratio correlated negatively with fetal growth. In four samples of amniotic fluids from cases of severe early-onset preeclampsia, the 35 kd protein falsely predicted lung maturity. All had abnormally high 35 kd protein/saturated phosphatidylcholine ratios (greater than 2 SD of controls). According to the present results, the 35 kd protein may give a false mature test result in severe preeclampsia.

Plasma antibodies to cow's milk are increased by early weaning and consumption of unmodified milk, but production of plasma IgA and IgM cow's milk antibodies is stimulated even during exclusive breast-feeding.

We measured levels of cow's milk-specific (CM) antibodies of immunoglobulin classes G, A and M by enzyme-linked immunosorbent assay in plasma of 198 healthy infants; a variable number of samples taken at birth and at ages of 2, 4, 6, 9, 12 and 28 months were available (altogether 765 samples). The rise in the level of IgG CM antibodies was highest and most rapid in infants exposed to CM formula before the age of 1 month. The level fell by 9 months, but rose again by 12 months. This second rise was attributed to the introduction of dairy milk. Partially breast-fed and fully weaned infants had similar levels of IgG CM antibodies. The levels of IgG CM antibodies were unaffected by the infants' own atopy, their heredity for atopy, and the umbilical serum level of IgG CM antibodies. IgA and IgM CM antibodies were absent at birth. Their levels increased similarly in exclusively breast-fed infants and infants fed CM formula. We conclude that plasma IgG antibodies to cow's milk are increased by early weaning and by consumption of unmodified cow's milk. Production of plasma IgA and IgM antibodies to cow's milk is stimulated even during exclusive breast-feeding.

Risk factors for infantile recurrent otitis media: atopy but not type of feeding.

We followed 183 infants from birth to 2.3 yr of age. Of these infants 28 had recurrent otitis media (ROM), defined as five or more separate episodes of otitis media (OM) during the first 2 yr of life or four such episodes during their 2nd yr. The OM presented during their 1st yr (early-onset ROM) in 12 infants and during their 2nd yr (2nd yr ROM) in 16. Eighty infants had no OM and served as a comparison group. Regarding type of feeding, the infants with early-onset ROM did not differ from their age-matched pairs in the comparison group either 1 month before the first OM or at the time of first episode of OM. Exclusive breast-feeding did not prevent OM and early weaning was not a risk factor for ROM. Atopy was associated with ROM with a relative risk of 1.9 (95% confidence limits 1.2-3.2). It was particularly prevalent among the infants with early-onset ROM, in 67 versus in 25% in the comparison group (p less than 0.01). During the 2nd yr daily contact with five or more children was associated with ROM with a relative risk of 2.1 (1.3-3.3). The infants with 2nd-yr ROM were in daily contact with more children than the comparison group (mean 11 versus 5; p less than 0.001). Parental smoking was more frequent among the infants with ROM than in the comparison group (54 versus 33%; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Purification of a hydrophobic surfactant peptide using high-performance liquid chromatography.

A 4- to 6-kDa hydrophobic peptide (SP4-6) was purified from human pulmonary surfactant. Sep Pak Florisil cartridges removed most of the lipids and the 18-kDa peptide. Analytical wide-pore reversed-phase HPLC column separated a single peptide that contained no detectable lipids (less than 1 nmol/2.5 micrograms protein). N-terminal analysis indicated that this peptide was pure, but the N-terminal amino acid was blocked. The peptide was capable of restoring the in vitro surface properties of synthetic phospholipids, which is characteristic of native lung surfactant.

Surfactant proteins in the diagnosis of fetal lung maturity. I. Predictive accuracy of the 35 kD protein, the lecithin/sphingomyelin ratio, and phosphatidylglycerol.

The concentration of the major surfactant protein with a molecular weight of 35 kD was determined in 469 amniotic fluid specimens from 284 pregnancies by the two-site simultaneous immunoassay with monoclonal antibodies. The predictive accuracy of the 35 kD protein was compared with that of the lecithin/sphingomyelin ratio and phosphatidylglycerol (the lung profile). Immature levels of 35 kD protein (less than 0.6 micrograms/ml) predicted 59% of all cases of respiratory distress syndrome (RDS) with an accuracy of 91%, and mature levels of 35 kD protein (greater than 3.0 micrograms/ml) predicted 68% of all infants who did not have RDS with an accuracy of 100%. The overall accuracy of the 35 kD protein in predicting the risk of developing respiratory distress syndrome was similar to that of the lung profile. In addition, testing with 35 kD protein improved the predictive value of an indeterminate lung profile (lecithin/sphingomyelin ratio of 1:1.9 and no phosphatidylglycerol) from 52% to 74%. The present results show that the lecithin/sphingomyelin ratio, phosphatidylglycerol, and 35 kD apoprotein have additive effects in improving the accuracy of the diagnosis of lung maturity.

Inositol supplementation in respiratory distress syndrome: relationship between serum concentration, renal excretion, and lung effluent phospholipids.

Inositol or placebo was given to 48 small preterm infants with respiratory distress syndrome (mean birth weight 1365 g, gestational age 30.1 weeks) between 48 hours and 10 days of age. The dose of inositol, 40 mg/kg every 6 hours, was at least as high as amounts received in full preterm human milk feedings. Serum inositol concentration increased between days 2 and 3 from a mean of 566 mumol/L to 823 mumol/L in the infants given supplement and fell from 451 mumol/L to 292 mumol/L in the controls. On day 16, serum inositol values remained higher in the infants given supplement than in those given placebo (mean 334 mumol/L vs 146 mumol/L, P = 0.014). The infants who developed bronchopulmonary dysplasia had significantly higher renal inositol clearance, lower inositol intake, and lower serum inositol concentrations. Inositol supplementation increased the saturated phosphatidylcholine/sphingomyelin ratio in tracheal aspirates. According to these results, supplementation with inositol in preterm infants leads to a rise in serum inositol concentration and improvement in the surfactant phospholipids. Inositol deserves further study as a dietary supplement for immature preterm infants who do not receive full human milk feeds.

Determination of trimethoprim in pediatric samples by high-performance liquid chromatography.

We describe and evaluate modifications to a known high-performance liquid chromatography assay of trimethoprim. The sensitivity, specificity and wide range of linearity (0.11-690 mumol/l) of this method make it suitable for analysing samples with large variations in volume and concentration. We have used it to study the pharmacokinetics of trimethoprim in children, including newborns. Automated injection is a useful option if the sample volume is not limited. The recovery (at 3.44 mumol/l) of the method was 99.8% with a coefficient of variation of 6.8% for manually injected samples. The corresponding results for automated injection were 97.9% and 12.8%.

Carnitine during prolonged breast feeding.

To assess carnitine levels during prolonged sole breast feeding we measured serum and breast milk carnitine concentrations in 37 lactating mothers and their healthy term infants from birth to the age of 1 yr. The number of solely breast-fed infants decreased to 31 at 2 months of age, to 28 at 6 months, and to seven at 9 months, because formula and/or solid food was added when there was not enough breast milk. In mothers the mean serum carnitine increased from 35 to 50 mumol/liter during the first 2 months after delivery and remained unchanged thereafter. Irrespective of the type of feeding, the mean serum carnitine in infants increased from 29 to 59 mumol/liter during the first 2 months, remained unchanged during 2-9 months, and decreased to the mean level of mothers thereafter. The mean carnitine concentration of breast milk was high (106 mumol/liter) immediately after delivery. During the first 2 months the mean carnitine concentration of milk decreased to the mean serum level of mothers and remained unchanged thereafter. The carnitine concentrations of serum and breast milk did not correlate, however. The mean daily carnitine intake of the breast-fed infants was 5.7 mumol/kg at 4 months of age, 4.7 mumol/kg at 6 months, and 6.0 mumol/kg at 9 months whereas the mean daily carnitine intake of the infants receiving formula was 28.9 mumol/kg at 1 month of age and 30.7 mumol/kg at 2 months. The serum concentration of carnitine in our infants did not correlate with carnitine intake. Our results indicate that serum carnitine concentrations are maintained during prolonged sole breast feeding.

Endobronchial surface active phospholipids in various pulmonary diseases.

In the present study we investigated the phospholipid composition of small-volume (up to 20 ml) in vivo bronchoalveolar lavage and that of quantitative ex vivo bronchoalveolar lavage. Furthermore, the accuracy of the small-volume lavage in predicting lung disease was evaluated. There was a positive linear correlation (r approximately equal to 0.87-0.91) between the amount of saturated phosphatidylcholine and the saturated phosphatidylcholine/sphingomyelin ratio in quantitative bronchoalveolar lavage. The phospholipid distributions in the small-volume lavage and the quantitative lavage were similar (r approximately equal to 0.78-0.94, n = 14). The overall accuracy of phosphatidylcholine/sphingomyelin ratio and phosphatidylglycerol/total phospholipid ratio in predicting the presence or absence of respiratory failure was 85-87% in newborns, children, and adults. In respiratory diseases without respiratory failure, the abnormalities in the phospholipids were frequent, although less distinct. According to animal experiments the surfactant system is inhibited at the onset of high permeability lung edema. Soon thereafter, the lavageable surfactant pool is decreased. Present findings support the view that surfactant defects are of importance in the pathogenesis of respiratory disease, and that surfactant-oriented therapy may be effective in the treatment and prevention of respiratory failure.

Difference in trimethoprim pharmacokinetics between children and adults.

We used a new micromethod, an application of a previously published high-performance liquid chromatography assay, to investigate trimethoprim (TMP) pharmacokinetics in children. The subjects were 5 girls who were treated for urinary tract infection with a TMP suspension, 6 mg/kg/day, twice daily for 10 days. Elimination studies were done after the last dose. The girls were 1.08-9.71 years old. 3 healthy adult males, aged 26.35-37.31 served as controls. The half-life (t 1/2) of TMP in the children was 3.0-5.5 versus 9.3-13.6 h in the adults. The volume of distribution (Vd) was 0.7-1.1 1/kg in the children and 0.5-0.9 1/kg in the adults. Plasma clearance (Clp) was 2.1-2.8 ml/min/kg for the children. The adults had a smaller Clp of 0.4-1.2 ml/min/kg. From this and previous studies we conclude that the t 1/2 of TMP is much shorter in children than in adults.

Increased IgM-type betalactoglobulin antibodies in children with recurrent otitis media.

Total concentrations of IgA, IgG, IgM and IgE, precipitating antibodies to cow milk, milk-specific IgE, as well as anti-milk antibodies and betalactoglobulin antibodies of the IgA, IgG and IgM classes determined by the ELISA method were studied and compared in children with recurrent otitis media, and children who had never had otitis. The children with recurrent otitis had a higher total IgE at 1 year of age and a higher total IgM at 3 years. The only difference in milk-specific antibodies was an increased titre of betalactoglobulin antibodies of IgM type in children with recurrent otitis. This new finding suggests that immunological mechanisms might play a part in recurrent otitis, which has been shown to be more common in bottle-fed than in breast-fed infants. So far, the role of betalactoglobulin antibodies in the pathogenesis of otitis media remains uncertain.

Gyrate atrophy of the choroid and retina with hyperornithinemia. Deficient formation of guanidinoacetic acid from arginine.

Patients with gyrate atrophy of the choroid and retina have 10- to 20-fold increased ornithine concentrations in body fluids and significantly reduced activity of ornithine aminotransferase in lymphocytes and cultured fibroblasts. We administered intravenous arginine to six patients and six controls to study in vivo inhibition by high ornithine concentrations of arginine-glycine transamidinase, the rate-limiting enzyme in creatine synthesis. Serum arginine concentrations curves after administration were similar for the two groups. The increment in serum ornithine was more than three times as great in patients as in controls. The mean half-times in plasma ornithine were 360 and 97 min, respectively. In the patients, the metabolic clearance of ornithine from the extracellular fluid was significantly delayed. Urinary guanidinoacetate excretion rose markedly in all controls, the excretion rate being higher in females. The patients always excreted less than the controls, the differences within the sexes being highly significant. Differences in creatine excretion after administration were less marked. We conclude that in gyrate atrophy patients, formation of guanidinoacetate, creatine, and possibly phosphocreatine is inhibited at the transaminidation step by the high concentrations of ornithine. Deficiency of the high-energy phosphates may underlie the pathogenesis of the eye and muscle atrophies.

Prolactin levels and bromocriptine treatment of short luteal phase.

Moderate hyperprolactinemia was found in 14 of 30 infertile patients with short luteal phase indicating a possible hypothalamic disorder in these patients. While the cycle length was normal, 28 days, late ovulation around day 18 of the cycle was characteristic of these patients. During bromocriptine treatment, 2.5 mg twice daily, ovulation took place earlier and luteal phase became longer irrespective of the basal serum prolactin level. The mean (+/- SEM) duration of luteal phase was 9.9 +/- 0.2 days in control cycles, and 11.7 +/- 0.5 and 12.2 +/- 0.3 days in two successive bromocriptine cycles (P less than 0.001). In patients taking bromocriptine, luteal phase became longer than 11 days in 37 of 60 treatment cycles, but no significant difference was recorded in the circulating progesterone and LH levels during mid- and late luteal phase. Three patients became pregnant and they all had normal baseline serum prolactin concentrations. Our results show that bromocriptine may be effective even when no apparent indication for prolactin suppression can be demonstrated.