Relationship between serum levels of methylguanidine and glycemic control in IDDM children.

OBJECTIVE: To examine the serum levels of methylguanidine in IDDM children and compare them with markers for glycemic control. Reports have indicated that active oxygen, which damages various tissues, increases in diabetes mellitus. The increase of active oxygen is one of the risk factors for diabetic complications. The synthesis of methylguanidine, a metabolic product of guanidine, is mainly regulated by active oxygen. RESEARCH DESIGN AND METHODS: Forty-eight children with IDDM (mean age 13.3 yr) and 17 age-matched nondiabetic control subjects were studied. Diabetic children were divided into a well-controlled group (HbA1c < 8%, n = 24) and a poorly controlled group (HbA1c > 8%, n = 24). Serum concentrations of methylguanidine were measured by enzymatic assay. RESULTS: Levels of methylguanidine in the poorly controlled group (1.31 +/- 0.08 microM) were significantly higher than those in both the well-controlled group (0.85 +/- 0.08 microM) and the control group (0.59 +/- 0.11 microM), respectively (P < 0.01). Methylguanidine levels showed a positive correlation with the levels of HbA1c (P < 0.01) or fructosamine (P < 0.01). No significant correlations were noted between methylguanidine levels and age, sex, duration of diabetes, or insulin dose. CONCLUSIONS: Our data indicate that the levels of methylguanidine in IDDM children might be affected by glycemic control and that the determination of serum methylguanidine levels could be a useful test for evaluating the state of diabetic control.

A new point mutation in the deoxyribonucleic acid-binding domain of the vitamin D receptor in a kindred with hereditary 1,25-dihydroxyvitamin D-resistant rickets.

Hereditary 1,25-dihydroxyvitamin D [1,25-(OH)2D]-resistant rickets (HVDRR) is a rare disorder characterized by rickets, alopecia, hypocalcemia, secondary hyperparathyroidism, and normal or elevated serum 1,25-dihydroxyvitamin D levels. We describe a patient with typical clinical characteristics of HVDRR, except that elevated levels of serum phosphorus were present coincident with increased levels of serum intact PTH. The patient was treated with high dose calcium infusion after an ineffective treatment with 1 alpha-hydroxyvitamin D3; serum calcium and phosphorus as well as intact PTH and alkaline phosphatase levels were normalized. Evaluation of phytohemagglutinin-activated lymphocytes derived from this patient revealed that 1,25-(OH)2D3 was unable to inhibit thymidine incooperation, a result that contrasts with the capacity of 1,25-(OH)2D3 to inhibit uptake into normal activated lymphocytes. 1,25-(OH)2D3 did not induce human osteocalcin promoter activity after transfection of this DNA linked to a reporter gene into patient cells. Cointroduction of a human vitamin D receptor (VDR) cDNA expression vector with the reporter plasmid, however, restored the hormone response. Evaluation of extracts from the patient cells for VDR DNA binding revealed a defect in DNA binding. Analysis of genomic DNA from the patient's cells by PCR confirmed the presence of a point mutation in exon 2 of the VDR. This exon directs synthesis of a portion of the DNA-binding domain of the receptor. We conclude that the genetic basis for 1,25-(OH)2D3 resistance in this kindred with VDR-positive HVDRR is due to a single base mutation in the VDR that leads to production of a receptor unable to interact appropriately with DNA.

Familial congenital hypopituitarism with central diabetes insipidus.

Congenital hypopituitarism (CH) presenting with central diabetes insipidus is typically associated with midline facial deformities or ophthalmological abnormalities. We present three brothers with CH and central diabetes insipidus not associated with any of these predisposing conditions. All three subjects presented with clinical features typical for CH (neonatal hypoglycemia, short stature, protruding forehead, and microgenitalia). All had hypoplastic genitalia indicating in utero gonadotropin deficiency, and all had complete GH deficiency. One represented low levels of thyroid hormones and TSH, indicating central hypothyroidism. Water deprivation examination in two of the brothers demonstrated complete arginine vasopressin deficiency in one and partial deficiency in the other. Magnetic resonance imaging indicated absence of the pituitary stalk, severe hypoplastic anterior pituitary in all three brothers, and absence of any posterior pituitary gland in two of the three. The other sibling had an ectopic posterior pituitary. This first report of familial CH with central diabetes insipidus may represent a previously unknown midline anomaly and provide new insights into the genetic control of pituitary and hypothalamic development.

Infantile neuroaxonal dystrophy: perinatal onset with symptoms of diencephalic syndrome.

In a neonatal case of infantile neuroaxonal dystrophy, there was emaciation, nystagmus, and endocrinologic disorder suggesting the diencephalic syndrome. At autopsy, spheroid bodies were widely disseminated, particularly in the hypothalamus, infundibulum, and neurohypophysis. The pathologic process may have started in utero.

Hyperresponsiveness of cough receptors in patients with bronchial asthma.

The hyperresponsiveness of cough receptors was evaluated using the acetic acid inhalation test in healthy adults, patients with bronchial asthma, and children with or without cough. The concentration of acetic acid inducing cough was more than 20% in all 16 healthy adults and 18 children in the control group. There were two groups of asthmatic patients: Those in group 1 showed normal response to more than 20% acetic acid (n = 46), and those in group 2 showed a sensitive reaction to less than 10% (n = 11). Mean age was 9.0 +/- 4.2 years in group 1 and 15.1 +/- 7.6 years in group 2 (statistical significance, P less than .001). Six of 11 asthmatic patients in group 2 were classified as nonallergic asthmatics, whereas only five of 46 patients in group 1 were nonallergic (P less than .01). Bronchoconstriction was not induced in any case, in spite of the production of cough. It is suggested that the hyperresponsiveness of individual cough receptors without the stimulation of irritant receptors be evaluated.

Gastroduodenal motility in neonates: response to human milk compared with cow's milk formula.

It is known that breast milk empties more quickly from the stomach than does infant formula. We studied the difference in gastroduodenal motility between neonates fed with human milk and those fed with infant formula. Twenty-four five- to 36-day-old neonates were fed with mother's breast milk or with a cow's milk-based formula. Postprandial gastroduodenal contractions were recorded manometrically for three hours. Repetitive, high-amplitude nonmigrating contractions were the dominant wave form during the postprandial period. The number of episodes, duration, amplitude, and frequency of nonmigrating contractions were not different following the different feedings. The migrating myoelectric complex, which signals a return to the interdigestive (fasting) state, appeared in 75% of breast milk-fed infants but only 17% of formula-fed infants (P less than .05) within the three-hour recording period. Because contractions were similar following the two meals, but a fasting state recurred more rapidly in breast-fed infants, we conclude that factors other than phasic, nonpropagated antroduodenal contractions were responsible for the differences in gastric emptying between breast milk and formula.

Attenuation of tachykinin-induced airflow obstruction and microvascular leakage in immature airways.

1. To study the effect of maturation on substance P (SP)- and neurokinin A (NKA)-induced airflow obstruction and airway microvascular leakage (MVL), we have measured changes in both lung resistance (RL) and extravasation of Evans blue dye in anaesthetized immature (aged 14 +/- 1 days) and adult guinea-pigs (aged 80 +/- 3 days). 2. RL and its recovery after hyperinflation at 5 min were measured for 6 min after i.v. SP (0.2, 1 and 30 nmol kg-1), NKA (1 and 10 nmol kg-1) or vehicle (0.9% NaCl). After measurement of RL, MVL in trachea, main bronchi and intrapulmonary airways was also examined. 3. The order of potency in inducing airflow obstruction did not change with age (NKA > SP) but immature animals required a larger dose of SP or NKA than adults to cause a significant increase in RL. 4. The order of potency in inducing airway microvascular leakage was SP > NKA in both immature and adult animals. The amount of extravasated dye after SP was significantly less in immature airways, especially in central airways. 5. Phosphoramidon (2.5 mg kg-1), a neutral endopeptidase (NEP) inhibitor, significantly increased RL after 0.2 nmol kg-1 SP only in adult airways. Phosphoramidon enhanced the dye extravasation after 0.2 nmol kg-1 SP in both immature and adult airways with a significantly greater amount of dye in adult animals, suggesting that mechanisms other than changes in NEP activity may be responsible for this age-related difference. 6. RL after hyperinflation following SP was not correlated with the degree of extravasation of Evans blue dye in immature animals, whereas it was closely correlated in adult animals. 7. SP and NKA may be less potent in causing both bronchoconstriction and microvascular leakage in immature airways. 8. Airway oedema caused by microvascular leakage may contribute less in immature airways to airflow obstruction after SP or NKA.

Inhaled furosemide prevents ultrasonically nebulized water bronchoconstriction in children with both atopic and nonatopic asthma.

To determine whether inhaled furosemide can modify the bronchoconstriction induced by ultrasonically nebulized distilled water (UNDW) in children with both atopic and nonatopic asthma, a single-blind, randomized, placebo-controlled study was undertaken. The UNDW inhalation challenge was performed in 21 asthmatic children (atopic, 14; nonatopic, 7; mean +/- SEM age, 11.5 +/- 0.5 years), who had a fall in FEV1 of at least 20 percent after distilled water inhalation. On separate days, these subjects underwent UNDW challenge test after inhalation of furosemide (10 mg/body square meters) or placebo (saline solution). Inhaled furosemide exerted a protective effect against bronchoconstriction induced by UNDW in children with both atopic and nonatopic asthma (p < 0.01, p < 0.05, respectively). These results indicate that the protective action of furosemide against UNDW-induced bronchoconstriction may be independent of its direct inhibitory effect on airway mast cell activation.

Inhaled diuretics attenuate acid-induced cough in children with asthma.

To evaluate the effect of inhaled diuretics, furosemide and amiloride, on cough induced by acid inhalation challenge in asthmatic children, a double-blind, randomized, placebo-controlled study was conducted. On separate days, 12 asthmatic children (10.3 +/- 0.7 [SEM] years) underwent acetic acid (AD) inhalation challenge after inhalation of furosemide (10 mg/m2 of body) amiloride (0.3 mg/m2 of body), or placebo (0.9% saline solution). Bronchoconstriction was not observed after administration of furosemide and amiloride. Both inhaled furosemide and amiloride exerted a protective effect against AA-induced cough in asthmatic children (p < 0.01 and p < 0.05, respectively), while there was little correlation between the individual protective potency of furosemide and amiloride against AA-induced cough (rs = 0.344, p = 0.255). These results demonstrate that both furosemide and amiloride can attenuate AA-induced cough, although, this protective effect of inhaled diuretics may not necessarily be dependent on Na(+)-K(+)-Cl- cotransporter or Na+ channel in airway epithelial cells.

Roxithromycin reduces the degree of bronchial hyperresponsiveness in children with asthma.

We evaluated the effects of a new semisynthetic macrolide antibiotic, roxithromycin, on the bronchial hyperresponsiveness to histamine in children with asthma. Twelve hospitalized asthmatic children, aged 11 to 15 years (mean age, 12.9 years), were enrolled in this study. They were treated with 150 mg of roxithromycin once a day orally for 8 weeks without any side effects. The PC20 value 4 or 8 weeks after the administration of roxithromycin increased significantly over the initial values (p < 0.05, p < 0.01, respectively). No significant change was observed in serum theophylline concentrations during this study. Serum cortisol level in the morning did not change after the administration of roxithromycin for 4 weeks. These results suggest that administration of roxithromycin may act favorably in the treatment of childhood asthma.

A prefecture-wide survey of mumps meningitis associated with measles, mumps and rubella vaccine.

A survey of untoward reactions, especially central nervous system reactions, after the administration of a newly introduced measles, mumps and rubella (MMR) vaccine in Gunma Prefecture, Japan, was initiated soon after 4 patients were hospitalized for aseptic meningitis. Thirty-five, 6 and 2 children developed meningitis, convulsive disorders and parotitis, respectively, within 2 months after MMR vaccination during the 8-month period extending from April to November, 1989. The time lag between MMR vaccination and meningitis ranged from 14 to 28 days in the 35 cases of meningitis. Mumps virus, isolated from the cerebrospinal fluid in 13 patients with aseptic meningitis, was characterized by determination of the nucleotide sequences of the P gene as mumps vaccine strain. The incidence of aseptic meningitis with positive mumps vaccine virus was estimated to be 0.11% (0.3% as a whole) during the 8 months from April to November and increased to 0.3% (0.7% as a whole) in September and October. We conclude that the incidence of aseptic meningitis after MMR vaccination seems to be higher than that reported previously.

Frequent lack of antibodies against human T-cell leukemia virus type I gag proteins p24 or p19 in sera of patients with adult T-cell leukemia.

Specificities of antibodies against human T-cell leukemia virus type I (HTLV-I) in sera of 27 patients with adult T-cell leukemia (ATL) were studied. All sera were positive for HTLV-I antigens by immunofluorescence assay using cells expressing HTLV-I antigens; sera from five ATL patients, however, did not react or hardly reacted with p19 or p24 gag proteins of HTLV-I upon immunoprecipitation assay. Therefore, the relationships among antibody specificities against HTLV-I, the proviral structures of HTLV-I genomes in leukemic cells, and the expression of viral antigens by leukemic cells after cultivation in vitro for a few days were examined. Analyses of the genomic structures of the proviruses revealed deletions in at least seven cases. However, we could not detect deletions in the proviral genomes of four out of the five ATL patients who lacked antibodies against gag proteins. Furthermore, expression of p19 and p24 was detected in these patients' peripheral blood lymphocytes (PBL) cultured in vitro for a few days. Thus, some ATL patients could not or could hardly raise antibodies against gag proteins, although they harbored complete HTLV-I genomes and their PBL expressed gag proteins in vitro. All patients harboring deleted proviruses, so far tested, raised antibodies not only against viral proteins that should be encoded by the integrated proviruses, but also against viral proteins that should be encoded by the deleted regions. Antibodies against viral proteins were detected also in sera of ATL patients whose PBL did not express viral proteins after in vitro cultivation. Specificities of antibodies against viral proteins in ATL patients could not be predicted by the structures of proviruses in leukemic cells or by expression of viral proteins in vitro. Immune responses to HTLV-I antigens were weak or lost in some ATL patients.

Bradykinin is less potent in causing airway microvascular leakage in immature than in adult guinea-pigs. Role of neutral endopeptidase.

To study the effect of maturation on bradykinin-induced airflow obstruction and airway microvascular leakage, we measured changes in both lung resistance (RL) and extravasation of Evans Blue dye in anaesthetized immature (aged 12 +/- 1 days) and adult guinea-pigs (aged 77 +/- 2 days). After measurement of RL after i.v. administration of bradykinin (2.5, 5 and 10 nmol/kg) or vehicle (0.9% NaCl), dye extravasation in the lower airways was examined in the same animal. Bradykinin did not cause a significant increase in RL in immature airways, whereas even 2.5 nmol/kg induced a significant elevation in adult airways. Bradykinin-induced extravasation of Evans Blue dye was greater in adult than in immature animals. Phosphoramidon (2.5 mg/kg), a neutral endopeptidase inhibitor, did not abolish the age-related difference in the amount of dye extravasated, suggesting that mechanisms other than changes in neutral endopeptidase activity may be responsible for the lower potency of bradykinin in inducing airway microvascular leakage in immature airways.

Platelet-activating factor-induced enhancement of superoxide anion generation in guinea-pigs.

We studied whether platelet-activating factor (PAF) enhances superoxide anion (O2-) generation in guinea-pigs. The production of O2- was assayed by chemiluminescence, using a Cypridina luciferin analog as a highly sensitive and specific probe for O2-. I.v. administered PAF significantly enhanced phorbol myristate acetate- or N-formyl-methionyl-leucyl-phenylalanine-induced O2- generation by guinea-pig alveolar macrophages or by polymorphonuclear leukocytes in a dose-dependent manner. The priming effect of PAF on O2- generation was maximal in cells harvested 5 min after administration of PAF. These responses were completely inhibited by administration of WEB 2086, a specific PAF receptor antagonist, or ONO-3708, a specific thromboxane A2 receptor antagonist, suggesting that the effects were mediated through the PAF receptor and thromboxane A2 generation. PAF might contribute to airway inflammation by enhancing O2- formation in addition to exerting other effects such as smooth muscle contraction or microvascular leakage.

The effect of non-steroidal anti-inflammatory drugs on the electrical properties of cultured dog tracheal epithelial cells.

The effect of non-steroidal anti-inflammatory drugs (NSAIDs) on the electrical properties of primary cultures of dog tracheal epithelium has been studied. The cells used were grown with an air interface in a serum-free medium on membranes coated with human placental collagen. When mounted in Ussing chambers at 37 degrees C, mean values for the baseline short circuit current (Isc) and the transepithelial resistance of 65 tissue specimens from 18 dogs were 24.0 +/- 3.2 microA/cm2 and 458 +/- 128 omega.cm2, respectively. These tissues had been pretreated with amiloride to abolish active Na+ absorption. Under these conditions, the Isc value serves as a measure of active Cl- secretion. The results of this study revealed that the Isc across a cultured monolayer of trachea was attenuated by the tested NSAIDs, indomethacin, fulfenamic acid, mefenamic acid, aspirin, and acetaminophen, with Ki's that ranged from 6.0 x 10(-5) to 2.51 x 10(-3) M. Salicylic acid had no effect on baseline Isc. The Isc sensitivity sequence to the Cl- channel inhibitors tested was: fulfenamic acid >> indomethacin > mefenamic acid >> aspirin > acetaminophen > salicylic acid. The NSAIDs also significantly inhibited both the transient, Ca(2+)-dependent and the sustained, cAMP-dependent increases in Isc elicited by isoproterenol. Thus, the tested NSAIDs appeared to have an effect on the electrical properties of the cells. A similar effect of NSAIDs on ion transport across the human airway epithelium may help to reduce airway fluid secretion.

Effect of maturation on histamine-induced airflow obstruction and airway microvascular leakage in guinea pig airways.

To study the effect of maturation on histamine-induced airflow obstruction and airway microvascular leakage, we measured concomitant changes in lung resistance (RL) and in extravasation of Evans Blue dye in the airways of anesthetized immature (aged 14 +/- 2 days) and adult guinea pigs (aged 60 +/- 12 days). RL was measured for 6 min after iv. histamine (0, 5, 15, 30 and 50 micrograms/kg). For comparison, responses after 1 microgram/kg substance P were also examined. After measurement of RL, microvascular leakage in trachea, main bronchi, and proximal and distal intrapulmonary airways was also examined in the same animal. Immature animals required a larger dose of histamine than adults to achieve a similar degree of maximal bronchoconstriction after histamine. In contrast, equal doses of histamine (15 and 30 micrograms/kg) induced a significantly greater extravasation of dye in immature airways in both proximal and distal intrapulmonary airways, although not in trachea or main bronchi. Substance P did not cause any age-related differences in dye extravasation at any airway level. These results suggest that i.v. histamine specifically causes a greater degree of airway microvascular leakage in peripheral airways but induces less smooth muscle contraction in the airways of immature guinea pigs than in the airways of adult animals.

Natriuretic activity of digoxin-like immunoreactive substance extracted from cord blood.

It was examined whether the digoxin-like immunoreactive substance (DLIS) extracted from cord blood has a natriuretic activity. The DLIS was prepared from cord blood of healthy fullterm infants by acetone-HCl extraction and a gel filtration column. A solution (solution A) containing 1.0 ng/ml of DLIS or another solution (solution B) consisting of solution A from which the DLIS had been completely absorbed by rat brain synaptosome, a crude digoxin receptor, were infused directly into the renal arteries of rats. Serum and urine were serially sampled. The excretion of sodium into the urine increased gradually after the initiation of infusion and reached a level two or three times higher than that before infusion (p less than 0.05). The infusion of a buffer solution or of the extract from which the DLIS had been absorbed by rat brain synaptosome did not significantly increase the urinary excretion of sodium. Statistical analysis showed a clear difference in the natriuretic activity between solutions A and B (p less than 0.01, p less than 0.05). Well-known natriuretic substances such as atrial natriuretic hormone, prostaglandin E2, F2 alpha, bradykinin and oxytocin dopamine were not detected enough to contribute to natriuresis in the extracts. From this data, we speculated that the DLIS in cord blood has a natriuretic activity and that it plays a role in water and sodium homeostasis in perinatal life.

Demonstration of the presence of digoxin-like immunoreactive substance (DLIS) in the serum and urine in children with nephrotic syndrome.

Longitudinal changes of digoxin-like immunoreactive substance (DLIS) in serum and urine from nephrotic children have been studied. The magnitude of DLIS in samples was measured by digoxin RIA kit. The binding activity to the ouabain receptor was measured by radioreceptor assay using crude rat brain synaptosomal fraction. In five cases of nephrosis, the mean value of DLIS in diuresis was significantly higher than during other stages (p less than 0.05). It was also higher than the levels recorded for six patients with nephritis (p less than 0.05). The presence of DLIS in the urine followed a similar pattern. The positive correlation between urine DLIS and ouabain-like substance (OLS) corrected by creatinine was observed for one month after the onset of nephrosis. The present study indicates the presence of DLIS in the serum and urine from patients with nephrosis which have the binding activity to the ouabain receptor. DLIS may be involved in natriuresis and may regulate active sodium transport in nephrotic children.

Two siblings with partial trisomy 1(q42.3-ter).

Two brothers, aged 6 and 4 years, with an unbalanced chromosome translocation (partial trisomy 1), and their mother, a balanced carrier of the translocation, t(1;3)(q42.3;p26.3), were described. Both patients show minor anomalies; a large head with a prominent forehead, low-set and soaring ears, a high-arched palate, a shallow nasal bridge, hypertelorism, and slender hands and feet. The manifestations in our cases were very mild compared to in the previously reported cases of partial trisomy 1. And our patients exhibit psychomotor retardation and ventricular dilatation on brain CT. We speculated that the amount of extra material reflects the phenotype. Our cases and previous reports indicate that the minimum clinical features of partial trisomy 1 are poor psychomotor development, a prominent forehead, and slender hands and feet. And many cases have macrocephaly with ventricular dilatation or hydrocephalus. So these features may be a key for the diagnosis of very mild partial trisomy 1.

Auditory brainstem responses in congenital heart disease.

To evaluate the effect of chronic hypoxemia on brainstem maturation, auditory brainstem responses were examined in 70 children (32 with and 38 without cyanosis) who had congenital heart disease. Ninety-one age-matched normal children served as controls. At 1-3 months of age, the I-V interpeak latencies of cyanotic infants (mean +/- S.D.; 5.17 +/- 0.17 ms) were more prolonged than were those of controls (4.95 +/- 0.11 ms) and those without cyanosis (4.84 +/- 0.22 ms; P < .05; P < .01). At 4-11 months of age, the I-V interpeak latencies of cyanotic infants (4.85 +/- 0.13 ms) were more prolonged than were those of controls (4.67 +/- 0.19 ms) and those not experiencing cyanosis (4.5 +/- 0.17 ms; P < .05; P < .01). In the cyanotic children, there was a significant negative correlation between the I-V interpeak latency and oxygen partial pressure (P < .01) or oxygen saturation (P < .05). Three of the 70 patients (4.3%) with congenital heart disease had absent auditory brainstem response. These data indicate that chronic hypoxemia may be one of the factors in retarded brainstem maturation.