[A new spacer, Babyhaler, for BDP inhalation therapy in severe infantile asthma]

Recently, it has been recognized that airway inflammation is the most important pathogenesis of bronchial asthma, and inhaled corticosteroids therapy is effective for childhood asthma. However, using metered dose inhalers (MDI) of beclomethasone dipropionate (BDP) is difficult for infants. In this study, we administered BDP inhalation therapy with a new spacer, Babyhaler, for five cases of early childhood with severe infantile asthma that we could not control even by combination of theophylline round the clock (RTC) therapy and disodium cromoglycate (DSCG) + beta 2 stimulant (beta 2) regular use. We compared symptom score of asthma attack between the pre-treatment period (prior 2 weeks) and post-treatment period (following 8 weeks) of BDP inhalation therapy with Babyhaler. As a result, symptom score decreased significantly within 4 weeks after treatment of BDP with Babyhaler as compared with the score before treatment of BDP. These findings suggest that Babyhaler is useful for BDP inhalation therapy in infantile asthma.

A novel specific bioassay for serum human growth hormone

Human GH receptor (hGHR) was recently expressed on a Ba/F3 cell line, which is a mouse pro-B cell lymphoma that has been induced to become a cloned cell line (Ba/F3-hGHR). Using a Ba/F3-hGHR cell line, we have established a bioassay for serum hGH. hGH stimulated cell proliferation in a dose-dependent manner in concentrations ranging from 1 ng to 100 ng/mL. Cell proliferation was not influenced by other hormones or growth factors in the bioassay, with the exception of insulin-like growth factor I (IGF-I) and GH binding protein. Free IGF-I significantly stimulated the proliferation of Ba/F3-hGHR cells at concentrations over 25.85 ng/mL in this bioassay system, but serum IGF-I did not stimulate cell proliferation because the sensitivity of cell proliferation was insufficient for free IGF-I in serum. GH binding protein, however, did suppress cell proliferation at the highest concentration (100 ng/mL), but did not at the average concentration (20 ng/mL). Human serum stimulated cell proliferation, which was completely suppressed by anti-GH antibody. The GH bioactivity of serum samples from normal children and patients with non-GH deficient short stature correlated strongly with the serum hGH concentration determined by immunoradiometric assay (IRMA) (r = 0.967, r = 0.924, P < 0.0001, respectively). The ratio of bioactivity/IRMA was 1.01+/-0.26 in sera from normal children and 1.18+/-0.24 and 1.00+/-0.29 at basal values and peak values in GH stimulation tests, respectively, in sera from patients with non-GH deficient short stature. The bioactivity/IRMA ratio for the serum GH bioactivity of a patient who had biologically inactive GH caused by an amino acid substitution was 0.333+/-0.056 (mean +/- SD). In conclusion, we established a new sensitive bioassay for hGH that is specific for hGH somatogenic action and is useful for screening of patients with short stature caused by biologically inactive hGH.

[Neonatal transient hypothyroidism]

Neonatal screening for congenital hypothyroidism can detect permanent and transient hypothyroidism. The latter condition is called neonatal transient hypothyroidism. This may result from various causes, but, especially, it should be suspected whenever there is a history of maternal autoimmune thyroid disease, including Hashimoto thyroiditis, Graves disease, hypothyroidism on replacement therapy, or recurrent congenital hypothyroidism of a transient nature in subsequent siblings. Transplacental TSH-receptor antibodies may affect fetal or neonatal thyroid function. Although thyroid dysfunction may be transitory, long-term follow-up is desirable.

Analysis of phyto-oestrogens by gas chromatography-mass spectrometry

The metabolites of oestrogenic substances of plant origin, phyto-oestrogens, have been proposed as cancer-protective agents in Asian and vegetarian populations. The two principle classes of these weak oestrogens are isoflavonoids and mammalian lignans. The former is derived from soya-based foods and the latter from oilseeds, cereals and whole grains. Asian populations such as the Japanese have high plasma concentrations of the isoflavones, daidzein and genistein, whereas vegetarians excrete large quantities of the lignan enterolactone, in their urine. The concentrations of these compounds in biological samples and foods are usually determined by GC-MS, although other techniques such as HPLC and LC-MS have also been used. A simple, robust method employing isotope dilution GC-MS will be described which could be applied to the determination of phyto-oestrogens in biological samples and food matrices. Briefly, samples are hydrolysed with β-glucuronidase, the aglycones extracted and the phyto-oestrogen fraction isolated by chromatography on Sephadex LH20. This fraction is then derivatised for GC-MS by reaction with N,O-bistrimethylsilyl-triflouroacetatamide to form trimethylsilyl derivatives. Using this technique we have determined the concentrations of the lignans, enterodiol and enterolactone, and the isoflavonoids, equol, daidzein and genistein, in the serum of men from Japan (n=42). The mean levels of daidzein and genistein in these men were 82.5 ng/ml (range 1.9-577) and 158.6 ng/ml (range 5.3-852), respectively. The majority of these men (57%) produced equol concentrations of >5 ng/ml, with a mean value of 26.7 ng/ml. Mean Levels of enterodiol and enterolactone were 0.6 and 9.4 ng/ml, respectively. The levels of daidzein and genistein produced from the hydrolysis of soya bean hulls, soya bean hypocotyl, dehulled soya beans, soya flour, soya grit and soya concentrates have also been determined by this method. Soya bean hypocotyl, for example, produces 2.1 mg/g of daidzein and 1.2 mg/g genistein, whereas some concentrates yield as much as 40% isoflavones.

Comparison between pre- and posttreatment clinical and renal biopsies in children receiving low dose ciclosporine-A for 2 years for steroid-dependent nephrotic syndrome

BACKGROUND

The dose of ciclosporine-A (CSA) for long-term treatment of nephrotic syndrome remains unclear due to the chronic nephrotoxicity of CSA.

PATIENTS AND METHODS

We examined 14 children with steroid-dependent nephrotic syndrome (SDNS) who showed signs of steroid toxicity and did not respond to cyclophosphamide. CSA was started at a dose between 2.0 and 3.3 mg/kg/day and the CSA dosage was decreased to between 1.6 and 3.1 mg/kg/day 4 months after the initiation of CSA therapy to maintain 40 to 70 ng/ml in the whole blood trough level.

RESULTS

Renal histology before CSA therapy showed minimal changes in all patients. It was possible to discontinue corticosteroid therapy within 3 to 4 months in all patients. The SD score for height significantly improved during CSA therapy. The incidence of CSA side-effects in our patients was lower than previously reported. Post-therapy biopsies after 24 months of CSA treatment showed mild tubular atrophy accompanying stripped interstitial fibrosis in only 1 patient (7%), and positive findings of global sclerosed glomeruli in 2 patients.

CONCLUSION

Long-term CSA therapy in low doses was effective for patients with SDNS and demonstrated a low incidence of CSA side-effects including nephrotoxicity.

Effects of the orally active non-peptide bradykinin B2 receptor antagonist, FR173657, on plasma extravasation in guinea pig airways

We investigated the effect of the orally active non-peptide bradykinin B2 receptor antagonist, FR173657 (E)-3-(6-acetamido-3-pyridyl)-N-[N-[2.4-di-chloro-3-[(2-methyl-8-quinoli nyl)oxymethyl]phenyl]-N-methy-laminocarbonylmethyl] acrylamide), on plasma extravasation mediated by activation of sensory nerves in guinea pig airways. Plasma extravasation was assessed by the photometric measurement of the extravasated Evans blue after formamide extraction. We found that the increase in Evans blue dye extravasation evoked by an aerosol of bradykinin (0.1 mM, 2 min) in the presence of phosphoramidon (2.5 mg/kg, i.v.) was abolished completely by FR173657 (20 mg/kg, p.o.) in the trachea and main bronchi. In sensitized guinea pigs pretreated with phosphoramidon, FR173657 (20 mg/kg, p.o.) inhibited plasma extravasation evoked by ovalbumin aerosol (5%, 2 min) by 77+/-14.2% in the trachea and 65+/-11.2% in the main bronchi. FR173657 (20 mg/kg, p.o.) did not affect the plasma extravasation caused by aerosolised capsaicin. These findings suggest that FR173657 is an orally active, promising anti-inflammatory agent for kinin-dependent inflammation following antigen challenge.

[Regulation of gonadotropin secretion]

Physiological gonadotropin levels are modulated by complex relationships between sex steroids and the hypothalamic gonadotropin-releasing hormone (GnRH) pulses. The frequency and amplitude of GnRH secretion provide signals for the differential regulation of LH and FSH secretion. At higher GnRH pulse frequencies, LH secretion increases more than FSH secretion, whereas, at lower frequencies, FSH secretion is favored. Gonadotropin secretion and subunit gene expression are regulated by sex steroids acting either directly at the pituitary level or indirectly by alteration of GnRH pulses from the hypothalamus. And sex steroids have positive or negative actions, depending on the model system and physiological state. Three gonadally derived peptides, inhibin, activin, and follistatin have been isolated and shown to have specific effects on FSH gene expression. Although gonadotropin regulation and reproductive function have not been fully determined, current molecular technologies will probably identify additional targets of sex steroids and GnRH action and allow greater insight.

Biologically inactive growth hormone caused by an amino acid substitution

Short stature caused by biologically inactive growth hormone (GH) is characterized by lack of GH action despite high immunoassayable GH levels in serum and marked catch-up growth to exogenous GH administration. We found a heterozygous single-base substitution (A-->G) in exon 4 of the GH-1 gene of a girl with short stature, clinically suspected to indicate the presence of bioinactive GH and resulting in the substitution of glycine for aspartic acid at codon 112. We confirmed the presence of mutant GH in the serum using isoelectric focusing analysis. The locus of mutation D112G was found within site 2 of the GH molecule in binding with GH receptor (GHR)/GH binding protein (GHBP). The expressed recombinant mutant GH tended to form a 1:1 instead of the 1:2 GH-GHBP complex normally produced by wild-type GH. The formation of a 1:2 GH-GHBP complex is compatible with the dimerization of GHRs by GH, a crucial step in GH signal transduction. Mutant GH was less potent than wild-type GH not only in phosphorylation of tyrosine residues in GHR, janus kinase 2 (JAK2), and signal transducers and activators of transcription 5 (STAT5) in IM-9 cells, but also in metabolic responses of BaF/GM cells, a stable clone transfected with cDNA of the chimera of the extracellular domain of human GHR, the transmembrane and the cytoplasmic domain of the human thrombopoietin receptor. These results indicate that the D112G mutation in the GH-1 gene causes production of bioinactive GH, which prevents dimerization of GHR and is therefore responsible for the patient's short stature.

Lipoprotein(a) phenotypes in Japanese children: a cohort study

BACKGROUND

Elevated serum lipoprotein(a) [Lp(a)] concentrations have been demonstrated to be associated with cardiovascular diseases due to premature atherosclerosis. However, the association of Lp(a) phenotypes with the development of these diseases remains largely unexplored.

METHODS

We analyzed the population-based frequencies of serum Lp(a) phenotypes in 269 Japanese children aged 8-13 years in one community. According to the different apolipoprotein(a) [apo(a)] electrophoretic mobilities, Lp(a) was classified into seven single-band and respective double-band phenotypes. Each individual expressed a single (homozygotic) or a double band (heterozygotic).

RESULTS

The serum Lp(a) concentration frequency distribution was skewed toward lower levels with a mean +/- SD of 15.5 +/- 18.0 mg/dl and a median of 11.0 mg/dl. The Lp(a) phenotype frequencies revealed that the frequency of double-band phenotype expression (55%) was higher than that of single bands (44%) and that the frequency of phenotypes representative of low molecular weight apo(a) was very low (2%). The mean serum Lp(a) concentration of the double-band-expressing subjects was higher than that of subjects with the single-band phenotype (20.1 +/- 19.9 vs. 10.5 +/- 15.9 mg/dl, p < 0.01).

CONCLUSIONS

These findings of Lp(a) phenotypes in children seemed to differ from those in Japanese adults in another study; contrary to expectation, the predominant Lp(a) phenotypes found in children were those frequently associated with cardiovascular diseases in adults. Thus, it is speculated that children whose Lp(a) phenotypes remain unchanged during the transition to adulthood may show an increased susceptibility to cardiovascular disease, although the nutritional effects on the Lp(a) phenotypes cannot be neglected.

Characterization of low-density lipoprotein subclasses in children

Low-density lipoprotein (LDL) particles are heterogeneous in density, size, and chemical composition, and this heterogeneity is thought to be genetically influenced. In the present study, plasma LDL subclasses in 248 children aged 7 to 13 years were analyzed by gradient gel electrophoresis. The prevalence of small dense LDL (SDLDL), a potent atherogenic LDL, was 9.3%, which is lower than that reported in adults. Furthermore, children with this LDL subclass showed increased body fatness and dyslipidemia, including elevated plasma triglyceride and apolipoprotein (apo) B concentrations and decreased plasma high-density lipoprotein (HDL) cholesterol and apo A-I concentrations, compared with children without this phenotype. These findings suggest that in addition to genetic factors, environmental factors that affect these cardiovascular risk factors may also influence expression of the SDLDL subclass.

Graves' disease associated with exophthalmos, cerebral ventricular dilatation and accelerated growth

A report is presented of a girl with Graves' disease, which was diagnosed at the age of 1.7 years. The mother had no thyroid disease. The patient developed signs of hyperthyroidism shortly before her first birthday, and the most prominent manifestations were accelerated skeletal maturation and linear growth, and dilatation of the brain ventricles. The latter manifestation, which has not been reported previously, was reversible upon normalisation of thyroid function with antithyroid treatment for three years.

Hyponatremia in central partial diabetes insipidus due to postoperative hypothalamic tumor

We report the case of a 4-year-old boy with a postoperative hypothalamic tumor, who exhibited unusual water and electrolyte disturbance. This developed as a late manifestation during the course of central diabetes insipidus (DI), which started when the patient was 2 years old. Clinically, hyponatremia and DI appeared alternately within 1 day. The hyponatremia (lowest value Na+ 115 mmol/I) was associated with afebrile convulsions. Assessment of fluid status revealed that the patient had a reduced capacity for arginine vasopressin(AVP) secretion (partial DI), which was not physiologically regulated and which was not concomitantly sufficient to produce maximally concentrated urine and allow the production of maximally diluted urine. This defective osmoreceptor function in association with the previously existing reduced capacity for AVP release seemed to be responsible for the fluid disturbance in the patient. The administration of nasal 1-desamino-8D-arginine vasopressin (DDAVP) only when urine output was increased, instead of regular administration at a fixed time, prevented both worsening of hyponatremia and development of DI.

Effect of testosterone on bone density and bone metabolism in adolescent male hypogonadism

To assess the influence of gonadal steroid testosterone (T) on bone mineral status in males during puberty, we observed the response of cortical bone density and serum biochemical parameters of bone metabolism to T treatment in 12 adolescent patients with hypogonadotropic hypogonadism (11 with both gonadotropin and growth hormone deficiency and one with isolated gonadotropin deficiency). The 12 patients aged 15 to 21 years (Tanner stage I to II) were divided into two groups: group 1 (n = 6) given T treatment for 2 consecutive years, and group 2 (n = 6) without T treatment for the first year and then with T treatment for the second year. Cortical bone density measured in the radius was less than the age-matched mean value for normal subjects in all 12 patients (groups 1 and 2) at the start of the study. Bone density in group 1 increased significantly during the 2-year T treatment period, but did not increase in group 2 during the first year without T treatment, although an increase was observed during the subsequent year with T treatment. Among circulating biochemical factors such as osteocalcin, parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OHD), and 1,25-dihydroxyvitamin D [1,25-(OH)2D], only osteocalcin showed an increase in response to T treatment in both groups. Levels of insulin-like growth factor-I (IGF-I) remained consistently low and did not change in any patients except one with isolated gonadotropin deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)