Radiological characteristics of skeletal growth in neonates and infants with achondroplasia

Achondroplasia (ACH) is the most common form of skeletal dysplasia characterized by a rhizomelic short stature. Radiological skeletal findings in pediatric and adult patients with ACH include short long bones, a relatively longer fibula compared to the tibia, a narrow lumbar interpedicular distance, and a hypoplastic iliac wing. Nonetheless, the characteristics of skeletal growth during the neonatal and infantile periods have scarcely been explored. Therefore, this retrospective study aimed to analyze the radiological skeletal growth during the neonatal and infantile periods in 41 Japanese patients with genetically confirmed ACH. The length of long bones in the upper and lower limbs and the lumbar interpedicular distances at L1 and L4 were measured. These parameters showed significant positive correlations with age. The upper segment-to-lower segment ratio in the lower limbs resembled the data of healthy controls from previous reports. The L1/L4 and fibula/tibia ratios increased with age, suggesting that some representative skeletal phenotypes of ACH were less distinct during the neonatal and infantile periods. In conclusion, for the first time, this study radiologically characterized skeletal growth during the neonatal and infantile periods of patients with genetically confirmed ACH.

Novel and recurrent COMP gene variants in five Japanese patients with pseudoachondroplasia: skeletal changes from the neonatal to infantile periods

Pseudoachondroplasia (PSACH) is an autosomal dominant skeletal dysplasia caused by pathogenic variants of cartilage oligomeric matrix protein (COMP). Clinical symptoms of PSACH are characterized by growth disturbances after the first year of life. These disturbances lead to severe short stature with short limbs, brachydactyly, scoliosis, joint laxity, joint pain since childhood, and a normal face. Epimetaphyseal dysplasia, shortened long bones, and short metacarpals and phalanges are common findings on radiological examination. Additionally, anterior tonguing of the vertebral bodies in the lateral view is an important finding in childhood because it is specific to PSACH and normalizes with age. Here, we report five Japanese patients with PSACH, with one recurrent (p.Cys351Tyr) and four novel heterozygous pathogenic COMP variants (p.Asp437Tyr, p.Asp446Gly, p.Asp507Tyr, and p.Asp518Val). These five pathogenic variants were located in the calcium-binding type 3 (T3) repeats. In four of the novel variants, the affected amino acid was aspartic acid, which is abundant in each of the eight T3 repeats. We describe the radiological findings of these five patients. We also retrospectively analyzed the sequential changes in the vertebral body and epimetaphysis of the long bones from the neonatal to infantile periods in a patient with PSACH and congenital heart disease.

A pediatric case of ureterolithiasis due to cystinuria accompanied by acute appendicitis; a case report

Introduction

Acute abdominal pain, a chief complaint frequently seen in the emergency department, can be triggered by a vast range of conditions. Although ureterolithiasis is a less common cause in children, renal colic can be caused by calculi due to hereditary metabolic diseases among patients in those age groups.

Presentation of case

We report a 12-year-old girl with abdominal pain who was diagnosed with concurrent acute appendicitis and ureterolithiasis due to cystinuria. Acute appendicitis was successfully treated with cefmetazole, and the calculus was eliminated after adequate fluid loading.

Discussion

Synchronous acute appendicitis and ureterolithiasis is reported to be rare. Cystinuria is a hereditary metabolic stone-forming disease, and the first calculi can be detected in childhood. Increasing the solubility of cystine in the urine is required to prevent recurrent stone formation and accompanying complications. Urinalysis, ultrasound, and computed tomography coincidentally demonstrated two different acute pathological processes of ureterolithiasis and appendicitis.

Conclusion

Careful physical and laboratory examination can help clinicians find coexisting etiologies of acute abdominal pain. Ureterolithiasis can be seen in children with hereditary disorders such as cystinuria. Early diagnosis of cystinuria and close monitoring may lead to a better long-term outcome.

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Abdominal pain can be caused by coexisting different disease processes.

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Patients with cystinuria usually experience the first stone formation in childhood.

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Diagnostic clues: cystine stone, hexagonal crystals, and urinary cystine excretion

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Treatments include adequate fluid intake, urinary alkalinization, and nutritional therapy.

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A proper selection of imaging modalities is needed for the assessment and follow-up.

Coronary artery lesions and the increasing incidence of Kawasaki disease resistant to initial immunoglobulin

BACKGROUNDS

Kawasaki disease (KD) is a systemic vasculitis of childhood involving coronary arteries. Treatment for intractable cases at a higher risk of cardiac sequelae remains controversial.

METHODS

Clinical outcomes of KD patients diagnosed in Yamaguchi prefecture, Japan between 2003 and 2014 were analyzed using the medical records from all 14 hospitals covering the prefecture. The study included 1487 patients (male:female, 873:614; median age at diagnosis, 24months).

RESULTS

The proportion of initial intravenous immunoglobulin (IVIG)-resistant patients increased from 7% to 23% during this decade, although no patients died. Twenty-four patients developed coronary artery lesions (CALs) over one month after the KD onset. The incidence of CAL in patients who received corticosteroid during the disease course (10/37; 27.0%) was higher than that in those who did not (14/1450; 0.97%, p=2.0×10(-35)). Nine patients who responded to initial IVIG plus corticosteroids had no CAL. Conversely, IVIG-resistant patients with alternate corticosteroid therapy more frequently developed CAL than those without it (10/28; 35.7% vs. 5/194; 2.6%, p=8.9×10(-10)). Multivariate analyses indicated corticosteroid therapy (p<0.0001), hyperbilirubinemia (p=0.0010), and a longer number of days before treatment (p=0.0005) as risk factors associated with CAL over a month after onset. The odds ratio of corticosteroid use increased from 18.3 to 43.5 if the cases were limited to initial IVIG non-responders and corticosteroid free-IVIG responders.

CONCLUSIONS

IVIG-failure has recently increased. The incidence of CAL increased in intractable cases with prolonged corticosteroid use. Corticosteroid may not be alternate choice for IVIG-failure to reduce the risk of cardiac sequelae.

Analysis of linear growth in survivors of childhood acute lymphoblastic leukemia

Therapy for childhood acute lymphoblastic leukemia (ALL) is entering a new era in terms of quality-of-life. In the current study, 21 patients with childhood-onset ALL were assessed for linear growth, bone mineral density (BMD), and endocrinological status, focusing especially on longitudinal analysis of the growth of each patient. Linear growth was uniformly attenuated during therapy in all patients. In contrast, after the cessation of therapy, the growth of each patient varied widely from attenuated to dramatic catch-up growth. In pubertal survivors who had received chemotherapy and cranial irradiation during prepuberty, the degree of growth after the cessation of therapy was negatively correlated with changes in height Z scores during therapy ( r = -0.76, P= 0.004). One of the factors involved in catch-up growth, urinary N-telopeptide/creatinine (U-NTx/Cr), was significantly higher in patients whose Z scores decreased after cessation of therapy ( P = 0.01), despite normal pubertal development and normal endocrinological assessments. The present study revealed individual differences in linear growth after the cessation of therapy and suggests the importance of catch-up growth during puberty.

Ultrasound assessment of tibial cortical bone acquisition in Japanese children and adolescents

The purpose of the present study was to evaluate the normal process of cortical bone acquisition during childhood and adolescence, and the relationship between speed of sound (SOS), measured by the Sound Scan 2000 system, and linear growth. A total of 1689 healthy Japanese children and adolescents (862 males and 827 females, aged 7-19 years) were enrolled in the study. SOS (m/s) was measured at the right tibial midshaft and the standard SOS values in the children and adolescents were generated. Various growth parameters were also measured. SOS of tibia increased significantly with age in both males and females (P < 0.001 each). In both sexes, a spurt in SOS was noted 1 year after the standard age at which Japanese peak height velocity (PHV; cm/year) occurs, and SOS increased markedly after the age at which the length of tibia reached a maximum. Multiple regression equations for SOS were generated as a function of various growth parameters; for males, SOS = 3047 + 6.2 x height (cm) + 2.1 x weight (kg) - 9.8 x length of tibia (cm) (R2 = 0.50; P < 0.001) and for females, SOS = 2713 + 10.3 x height (cm) + 1.8 x weight (kg) - 15.5 x length of tibia (cm) (R2 = 0.49; P < 0.001). In both sexes, SOS correlated positively with body height and weight, but negatively with length of tibia. Our results indicate that SOS is quite useful for evaluating cortical bone status in children and adolescents; the results of these measurements may provide an explanation for the relative weakness of the mechanical properties of the bone during childhood and adolescence.

An ultrasensitive assay revealed age-related changes in serum oestradiol at low concentrations in both sexes from infancy to puberty

OBJECTIVE

Intensive studies of oestrogen receptors have suggested extragonadal functions of oestrogen. However, the in vivo extragonadal functions of oestradiol remain unclear because of the lack of an adequate assay system at low concentrations. In this study, we assessed the usefulness of a new ultra-sensitive assay for children.

METHODS

Serum oestradiol was measured with an ultrasensitive assay (assayable concentration: 5-1,835 pmol/l: ESTR-US-CT, CIS biointernational, France). Intra- and interassay coefficients of variation at low concentrations (< 36.7 pmol/l) were 8.2 +/- 6.8 (0.1-31.2)% and 8.3 +/- 3.7 (7.5-12.9)%, respectively.

SUBJECTS

Sera from 88 healthy children (55 males and 33 females; 1 month to 16 years old) and 31 patients who underwent gonadal suppression therapy were analysed.

RESULTS

Age-related changes were observed in both sexes. Serum oestradiol concentrations in childhood decreased slightly compared to those in infancy, then increased at puberty. Most prepubertal children showed oestradiol concentrations lower than 36.7 pmol/l. A study on patients who underwent gonadal suppression therapy revealed oestradiol changes within low concentrations, depending on the stage of the therapy.

CONCLUSIONS

The new assay was considered precise enough for the assessment of oestradiol secretion at low concentrations in childhood. Age-related changes in serum oestradiol suggested gonadal activity in the prepubertal period. This assay could be a powerful tool for investigating novel oestradiol functions in vivo.

Growth hormone therapy in achondroplasia

Achondroplasia is one of the most common causes of severe rhizomelic dwarfism. We have previously reported the growth-promoting effect of growth hormone (GH) in this disorder. In this expanded clinical study, dose dependency and the long-term effect of GH were also investigated. Prepubertal children with achondroplasia (82 males and 63 females) were randomly divided into 2 groups. Patients were treated with 0.5 IU/kg per week or 1.0 IU/kg per week subcutaneous recombinant human GH. Of 75 patients, the mutational analysis of fibroblast growth factor receptor-3 revealed that G1138A was detected in 70 and G1138C was found in 2. GH increased growth rate and height z score in a dose-dependent manner. GH also increased serum insulin-like growth factor (IGF)-I, IGF-binding protein-3 and osteocalcin. No adverse effects were observed in either group. We conclude that GH therapy is a useful method for improvement of severe growth retardation of achondroplasia.

Control of melanosome movement in intact and cultured melanophores in the bitterling, Acheilognathus lanceolatus

The melanophores in the dermis on scales in the bitterling, Acheilognathus lanceolatus were studies to obtain information about the control mechanism of aggregation and dispersion using intact, membrane-permeabilized and cultured cells. The cultured melanophores showed supersensitivity, namely, they responded to norepinephrine with much higher sensitivity than intact cells. The cultured melanophores failed to respond to high KCl. Melatonin aggregated and adenosine dispersed melanosomes within a cell. Digitonin permeabilized cells showed aggregation with Ca ions and dispersion by cyclic adenosine 3',5'-monophosphate (cAMP) in the presence of ATP. Movement of melanosomes was observed under the high magnification of light microscope and the tracks of each pigment granule were followed. The granules moved fast and linearly during aggregation, whereas they showed to-and-fro movement during dispersion.

The clinical usefulness of liquid human growth hormone (hGH) (Norditropin SimpleXx in the treatment of GH deficiency

Human growth hormone (hGH) is an essential therapeutic drug for the treatment of GH deficiency. The development of recombinant GH using a pen injection system has enabled easy and safe treatment of GH-deficient patients; however, the process of dissolving hGH in the powder form is complicated and dangerous. In this study, we investigated the usefulness of a newly developed liquid form of hGH (Norditropin((R)) SimpleXx(TM)) in the treatment of 51 patients with GH deficiency. Fifteen previously untreated patients with GH deficiency were treated with liquid hGH (group A), and 36 patients who had previously used hGH in the powder form were changed to the liquid form (group B). Both groups were treated with liquid hGH 0.5 IU/kg per week for 6 months. The growth rate of patients in group A increased from 4.0 +/- 2.4 cm/year to 9.2 +/- 2.9 cm/year. The patients in group B continued to grow at the same rate as before using the liquid hGH therapy. Questionnaires to the patients in group B demonstrated that 85% preferred the convenience of using the new liquid form of hGH. Our results indicate that liquid hGH has similar efficacy to that of powder hGH, but its improved convenience may have a beneficial effect on patient compliance.

Vitamin D is an important factor in estrogen biosynthesis of both female and male gonads

In the present study, the role of vitamin D in the regulation of estrogen synthesis in gonads was investigated. Vitamin D receptor null mutant mice showed gonadal insufficiencies. Uterine hypoplasia and impaired folliculogenesis were observed in the female, and decreased sperm count and decreased motility with histological abnormality of the testis were observed in the male. The aromatase activities in these mice were low in the ovary, testis, and epididymis at 24%, 58%, and 35% of the wild-type values, respectively. The gene expression of aromatase was also reduced in these organs. Elevated serum levels of LH and FSH revealed hypergonadotropic hypogonadism in these mice. The gene expressions of estrogen receptor alpha and beta were normal in gonads in these mice. Supplementation of estradiol normalized histological abnormality in the male gonads as well as in the female. Calcium supplementation increased aromatase activity and partially corrected the hypogonadism. When the serum calcium concentration was kept in the normal range by supplementation, the aromatase activity in the ovary increased to 60% of the wild-type level, but LH and FSH levels were still elevated. These results indicated that vitamin D is essential for full gonadal function in both sexes. The action of vitamin D on estrogen biosynthesis was partially explained by maintaining calcium homeostasis; however, direct regulation of the expression of the aromatase gene should not be neglected.

Thyroid-stimulating antibody in a patient with euthyroid Graves' disease

We report an 11-year-old girl with euthyroid Graves' disease. She was referred to our clinic because of left exophthalmos without other symptoms suggestive of hyperthyroidism. Her serum concentration of free thyroxine (FT4) and free triiodothyronine (FT3) were normal, but thyroid-stimulating hormone (TSH) was below normal and impaired TSH response to TSH releasing hormone (TRH) was found. Although the sera were positive for anti-TSH receptor antibody (TRAb) and thyroid-stimulating antibody (TSAb), both titers were not as high as usually observed in Graves' disease. Three months later, she developed hyperthyroidism and was treated with propylthiouracil. Within 2 weeks of the initiation of therapy, all symptoms except exophthalmos disappeared, and after 2 months of treatment TRAb was negative though TSAb remained positive. TSAb is therefore a good indicator to use in the diagnosis and follow-up of euthyroid Graves' disease and should be measured in patients with exophthalmos of unknown origin, even in children.

Altered biochemical markers of bone turnover in humans during 120 days of bed rest

Microgravity induces significant and progressive bone loss in both humans and animals. This is the consequence of disturbed bone remodeling. We performed a bed rest experiment to simulate microgravity and tried to clarify bone metabolism by measuring biochemical markers of bone turnover. Six healthy volunteers participated in 120 days of bed rest. The parameters of calcium homeostasis, calcitropic hormones, and biochemical markers of bone turnover were examined. After ambulatory control evaluation, all subjects underwent 120 days of bed rest. Metabolic evaluation was performed in a baseline period, and on days 7, 16, 50, 72, 92, and 108 during bed rest, and on days 10 and 25 during a recovery period. Bed rest induced an increase in urinary calcium (Ca) excretion and serum Ca and bone resorption markers. Urine pyridinoline, deoxypyridinoline, and type I collagen cross-linked N-telopeptide increased more rapidly than urinary Ca excretion and serum Ca. Tartrate-resistant acid phosphatase (TRAP) increased even in the recovery period. Carboxy-terminal propeptide of type I collagen, a bone formation marker, significantly decreased on days 50, 92, and 108 of bed rest. These changes of biochemical markers of bone metabolism, except for TRAP, rapidly returned toward control levels in the recovery period. Immunoreactive parathyroid hormone showed a modest decrease during bed rest and a significant increase in the recovery period. Insulin-like growth factor I (IGF-I) and its binding protein, insulin-like growth factor binding protein-3, increased during bed rest, indicating the possibility of resistance to IGF-I in bones under reduced mechanical stress and strain. Bone loss from unloading results from the combination of acceleration of bone resorption and subsequent retardation of bone formation.

Molecular defects in achondroplasia and the effects of growth hormone treatment

Achondroplasia is a common skeletal dysplasia with severe growth retardation. Recently, mutations in the fibroblast growth factor receptor 3 (FGFR3) were identified in patients with achondroplasia. In the present study, 70 of 75 Japanese patients with achondroplasia were found to have a G1138A mutation in FGFR3, and two patients had a G1138C mutation. Growth hormone therapy was given to 145 patients with achondroplasia. Significant dose-dependent effects on skeletal growth were obtained, with no long-term adverse effects.

Potential role of rhIGF-I/IGFBP-3 in maintaining skeletal mass in space

Bone loss during space flight may be induced by decreased activity of bone formation. To explore a new method for the bone loss in microgravity, the effects of insulin-like growth factor I (IGF-I), a potent stimulator for osteoblast activities, were studied in in vitro and in vivo system. The complex of IGF-I and its specific binding protein, IGFBP-3, may stimulate the osteoblastic activities via prolonged serum half life and increased cellular association of IGF-I. In an ovariectomy combined with neurectomy model, this complex stimulated bone turnover. IGF-I/IGFBP-3 may be a candidate for the treatment of bone loss induced by the microgravity.

Recent progress in diagnosis and treatment of osteogenesis imperfecta

Osteogenesis imperfecta (OI) is an inheritable disorder characterized by bone fragility with various symptoms of connective tissue disorders. OI is commonly classified by Sillence's classification into four types according to the clinical features. The cardinal symptom is pathologic fracture, which is often recognized before birth, is frequent during infancy and childhood, then decreases at puberty. Bone mineral density is markedly decreased in OI, especially of the lumbar spine. Bone deformities are frequently observed in the long bones of the extremities, and spinal deformities and compression fractures are also common. Growth retardation is extremely severe, especially in type III. Calcitonin has been the most common therapy for OI. Recently, bisphosphonates have been found to be potent drugs that increase bone mass in OI patients. To prevent further fracture or bone deformity, appropriate orthopedic managements, including intramedullary rodding, are critically important. Growth hormone is effective in stimulating bone growth during childhood. The pathogenesis of OI is quantitative or qualitative abnormalities of type I collagen. The clinical features of each type usually correspond to the type of mutation. Several possibilities for gene therapy have been proposed.

Serum bone alkaline phosphatase isoenzyme levels in normal children and children with growth hormone (GH) deficiency: a potential marker for bone formation and response to GH therapy

Serum bone alkaline phosphatase (B-ALP) has been considered to be a good marker for bone formation. Recently, a specific immunoradiometric assay for serum B-ALP has been developed. Using this system, we measured the serum levels of B-ALP in 363 normal children (207 males and 156 females, age 0-18 yr) and in 20 GH-deficient children (age 5-13 yr) who showed significant bone growth during GH therapy. We found the following results. 1) There were no significant circadian variations in serum B-ALP levels (coefficients of variation: 2.10-9.66%). 2) In normal children, serum B-ALP levels were high in infants and gradually declined and increased again during puberty. During the pubertal period, the highest serum B-ALP values were observed at midpuberty (stage 3 of breast and pubic hair development and 4-12 mL of testicular volume). 3) Serum B-ALP levels were significantly correlated with levels of the carboxy-terminal propeptide of type 1 procollagen (r = 0.447, P < 0.0001) and osteocalcin (r = 0.433, P < 0.0001). 4) After beginning GH therapy, serum B-ALP levels increased significantly; a 26% increase in serum B-ALP level was observed after 3 months of GH therapy. 5) The ratio between serum B-ALP level after 3 months of GH therapy and before GH therapy was positively correlated with the GH-induced improvement in the height SD score (height SD score after 1 yr of GH therapy minus that before GH therapy) and improvement in the height velocity SD score (height velocity SD score during GH therapy minus before GH therapy) (r = 0.531, P < 0.05 and r = 0.608, P < 0.01, respectively). 6) The increment of SD score in serum B-ALP level after 1 yr of GH treatment was also significantly correlated with that for bone mineral density after 1 yr of GH therapy (r = 0.663, P < 0.005). These results show that B-ALP levels are a useful marker for bone formation because B-ALP levels increased when the growth rate accelerated. Serum B-ALP is a potential predictor of the effectiveness of GH therapy, because the serum level after 3 months of GH therapy reflects the outcome of 1 yr of GH therapy.

Serum insulin-like growth factor binding protein-3 in the hypophosphatemic mouse: decreased activity and abnormal modulation by dietary phosphate

The hypophosphatemic mouse, the murine homologue of X-linked hypophosphatemia, is characterized by renal defects in phosphate reabsorption and 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) production and by an osteoblast dysfunction. In view of the potential importance of insulin-like growth factors (IGFs) in the regulation of these processes and the role of IGF-binding proteins (IGFBPs) as modulators of IGF action, we asked whether Hyp mice have alterations in IGFs or IGFBPs. Using specific radioimmunoassays and Western ligand blot analysis, we evaluated serum levels of IGFs (IGF-1 and IGF-II) and IGFBPs, respectively, in normal and Hyp mice. We also examined the effect of dietary phosphatase on these parameters. Serum levels of IGF-1 and IGF-II in Hyp mice were not significantly different from those in normal mice, but IGFBP-3 levels were significantly lower (70% of normal, p < 0.05) in the mutant strain. The other IGFBP species appear unchanged. Phosphate supplementation normalized serum phosphate levels in Hyp mice and elicited a significant decrease in serum IGF-I levels (23%, p < 0.05) and a further deduction in IGFBP-3 (22%, p < 0.02). Phosphate deprivation induced hypophosphatemia IGF-II. The present results indicate that the low serum IGFBP-3 activity in Hyp mice is not related to hypophosphatemia per se. Based on the documented effects of parathyroid hormone (PTH) on IGF-I and IGFBP-3, we propose that the secondary hyperparathyroidism displayed by Hyp mice and its exacerbation by phosphate supplementation may contribute to low IGFBP-3 levels in control Hyp mice and to the decreases in serum IGF-I and IGFBP-3 in phosphate-supplemented Hyp mice.

Malignant osteopetrosis treated with high doses of 1 alpha-hydroxyvitamin D3 and interferon gamma

A male infant with malignant osteopetrosis was treated with high doses of 1 alpha-hydroxyvitamin D3 and interferon gamma. Therapy with 1 alpha-hydroxyvitamin D3 increased the serum calcium level despite the markedly elevated serum level of 1 alpha, 25-dihydroxyvitamin D before treatment. Recombinant human interferon gamma increased neither the bone mineral nor matrix turnover, and was not tolerated because of bone marrow suppression.

Growth hormone (GH) treatment in achondroplasia

Achondroplasia is one of the most commonly known types of skeletal dysplasia in the adult leading to short stature. Before beginning growth hormone (GH) treatment of short stature in patients with achondroplasia, we evaluated their growth pattern and their hypothalamic-pituitary function, including GH secretion. We studied 22 patients with achondroplasia (7 males and 15 females: age range, 3 to 12 years). The z-score of their height at admission was -5.4 +/- 1.2 (mean +/- SD), and that of their annual height gain before admission was -3.1 +/- 1.3 (mean +/- SD). GH response to provocative tests was normal in all patients except five: four showed subnormal (< 10 ng/ml) response to L-Dopa stimuli, and one patient showed subnormal (< 20 ng/ml) response to GRF stimuli. The mean GH concentration during sleep was found to be low (< 5 ng/ml) in three patients. These three patients were suspected to have latent GH deficiency, as they also showed a markedly low IGF-1 level and marked delay of bone age. LH, FSH, TSH, and cortisol response to provocative tests were normal in all the patients. We treated this group of patients with recombinant human GH (1 IU/kg/week). In 18 patients who were treated with GH for more than 6 months, height velocity during GH therapy was significantly increased compared to that before GH therapy (4.1 +/- 0.8 cm/year vs 7.2 +/- 1.4 cm/year). We conclude that parameters reflecting hypothalamic-pituitary function, particularly GH secretion, should be examined in achondroplasia patients, and that GH treatment may be beneficial in the treatment of short stature in achondroplasia.

Urinary glycylprolyl dipeptidyl aminopeptidase (GP-DAP) in insulin-dependent diabetic patients

Urinary glycylprolyl dipeptidyl aminopeptidase (GP-DAP) concentrations were determined in 36 insulin-dependent diabetic children aged 4-18 years with a duration of diabetes ranging from 1 month to 14 years. Abnormal urinary GP-DAP concentrations were found in 19 of the 36 patients. Twelve of 27 patients without microalbuminuria also had increased urinary concentrations of GP-DAP. There was a significant correlation between urinary GP-DAP and plasma fructosamine (r = 0.52, p < 0.001). Our data suggest that urinary GP-DAP may be used as a marker for diabetic nephropathy. However, there is also a possibility that increased urinary GP-DAP concentrations are functionally related to poor metabolic control. Longitudinal studies are needed to establish the clinical usefulness of urinary GP-DAP.

Serum propeptide and intact molecular osteocalcin in normal children and children with growth hormone (GH) deficiency: a potential marker of bone growth and response to GH therapy

To establish a sensitive marker for bone formation we have developed a sandwich enzyme-linked immunosorbent assay for intact osteocalcin (OC) and its propeptide. Serum levels of these peptides were studied in 185 normal children, aged 4-15 yr, and in 23 GH-deficient children treated with GH. The serum levels of the propeptide in normal prepubescent children were 1.43 +/- 0.23 (mean +/- SE) micrograms/L in boys and 1.53 +/- 0.23 micrograms/L in girls. The peak value occurred at the age of 13 yr in boys (2.91 +/- 0.42 micrograms/L) and 11 yr in girls (2.34 +/- 0.34 micrograms/L). The serum intact OC levels in prepubescent boys and girls were 18.8 +/- 2.1 and 20.7 +/- 2.1 micrograms/L, respectively, and these levels increased to 41.0 +/- 3.7 micrograms/L in boys aged 13 yr and to 27.0 +/- 2.5 micrograms/L in girls aged 11 yr. In the GH-deficient patients, a 2.3-fold increase in the propeptide level and a 1.7-fold increase in the intact OC level was observed after 1 month of GH therapy. Serum propeptide and intact OC levels after 1 month of GH therapy correlated with the growth response after 12 months of GH therapy (r = 0.660 and P < 0.01, for propeptide; r = 0.537 and P < 0.01 for intact OC). These results show that since both propeptide and intact OC in serum were increased when the growth rate was elevated, these peptides are sensitive markers of bone formation. Serum levels of these peptides, particularly propeptide, after 1 month of GH therapy might be a helpful predictor of the growth response to long term GH therapy.

Growth hormone deficiency and empty sella syndrome in a boy with dup(X) (q13.3----q21.2)

A 2 8/12-year-old boy with severe growth failure and mental retardation was found to have a maternally derived tandem duplication of the long arm of X chromosome, dup(X) (q13.3----q21.2). Karyotypic interpretation was further confirmed in this patient by a double gene dose for red blood cell phosphoglycerate kinase. DNA replication study showed that the duplicated X chromosome was always late replicating in peripheral blood lymphocytes as well as in skin fibroblasts from the mother. Endocrine studies in the patient demonstrated growth hormone deficiency. Magnetic resonance imaging of the head then disclosed the empty sella syndrome. This appears to be the first report of a dup(Xq) patient associated with a growth hormone deficiency and the empty sella syndrome. We emphasize that duplication of the proximal Xq in males represents another microduplication syndrome (Thode-Leonard syndrome).

1,25-Dihydroxyvitamin D3 stimulates the secretion of insulin-like growth factor binding protein 3 (IGFBP-3) by cultured human osteosarcoma cells

Several types of specific insulin-like growth factor binding proteins have been reported. These binding proteins are produced by peripheral tissue-derived cells and they modulate the functions of insulin-like growth factors. In this study, we investigated both the secretion of insulin-like growth factor binding protein 3 (IGFBP-3) from a human osteosarcoma cell line MG63, and the effects of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) on the production of this binding protein. The beta subunit of IGFBP-3 was detected in perinuclear cytoplasm of MG63 cells by immunocytochemical study. Immunoblotting and SDS-PAGE analysis revealed that both 150KD MW entire molecules and 40-60KD MW beta subunit molecules of IGFBP-3 were present in cell-conditioned media. 1,25-(OH)2D3 stimulated the production of the IGFBP-3 molecule by MG63 cells. The concentration of IGFBP-3 in conditioned media began to rise at 12 hours after the addition of 10(-8) M of 1,25-(OH)2D3 and reached peak level at 48 hours. Dose-dependent effects of 1,25-(OH)2D3 were demonstrated. The its maximum effect was observed at 10(-10) M. The concentration of IGFBP-3 in cytosol also increased at a 10(-10) M concentration of 1,25-(OH)2D3. We conclude from these results that human osteosarcoma cells MG63 produce the IGFBP-3 molecule and that 1,25-(OH)2D3 stimulates the production of this protein. These data suggests that the synergistic effects of 1,25-(OH)2D3 on the action of IGF-I on osteoblastic cells, which we reported previously, may be modulated by locally produced IGFBP-3.

Age-related changes in urinary growth hormone level and its clinical application

In order to establish the normal range of urinary growth hormone (GH) level for age and sex, which is important in the clinical application of urinary GH to diagnosis, we measured GH in the first morning urine specimens of 270 normal subjects aged 3 to 20 years. Urinary GH levels in patients with documented GH deficiency were compared with those of the normal controls. In normal subjects, urinary GH levels showed a statistically significant change with age. They were relatively high in infancy and mid-puberty, reaching a peak at 11 to 12 years in girls and at 13 to 14 years in boys. Urinary GH levels in patients with complete GH deficiency were apparently lower (less than -2.0 SD) than those of the normal children, while the levels in patients with partial GH deficiency overlapped with the normal range. When assessing GH secretion by using urinary GH measurement, consideration of age and sex is required, since the level changes significantly with these factors.

[Anticonvulsant effects of bifemelane hydrochloride on kindled seizures from the amygdala and hippocampus in rats]

The anticonvulsant affects of bifemelane hydrochloride, a novel therapeutic drug for cerebrovascular dementia, were investigated in the kindling model of epilepsy in rats. The results obtained were as follows. (i) Both the seizure stage and afterdischarge duration of kindled seizures from the amygdala and hippocampus were significantly suppressed following systemic injection of bifemelane hydrochloride (5-30 mg/kg) in a dose-dependent manner. (ii) The efficacy of anticonvulsant action on kindled seizures from the hippocampus was more potent than from the amygdala. (iii) The maximum anticonvulsant effects were observed between 1 and 4 h after injection, and this time course was very similar to that of the previously reported increasing effects of bifemelane hydrochloride on noradrenaline levels in the rat brain. Thus, it is suggested that these anticonvulsant effects in kindling may be mediated by central noradrenergic systems. These results indicate that bifemelane hydrochloride has a potent anticonvulsant action on kindled seizures and may be useful for dementia patients with epilepsy or other seizure disorders.

[The effect of a novel TRH analog (DN-1417) on postictal seizure inhibition in amygdaloid kindled cats]

Anticonvulsant and prophylactic effects of DN-1417, a novel TRH analog, were reported previously in kindled cat preparations which had been established as an experimental model of epilepsy. This study was conducted to examine an effect of DN-1417 on postictal events including postictal seizure inhibition (PSI). A recycling paradigm consisted of 8 amygdaloid stimuli at 1 hour intervals was applied to evaluate the PSI. Six of bilateral amygdaloid kindled cats were used. In control session, the left amygdala had been stimulated at final electroconvulsive threshold at 1 hour intervals in all cats. In drug session, the cats were pretreated with DN-1417 (4 mg/kg, i.v.) and exposed to recycling paradigm 20 minutes after the administration. The interval of each session was at least 2 weeks EEG recordings and behavioral observations were carried out at the same time. Effects of TRH tartrate (4 mg/kg, i.v.) on PSI was also investigated in 2 cats at the same paradigm. PSI was significantly prolonged and postictal EEG silence was significantly shortened by DN-1417. The pretreatment of TRH tartrate showed an prolongation of PSI in 2 cats respectively. These results suggest that administrated TRH analog or TRH may inhibit an occurrence of subsequent seizures and prevent the epileptic status.

Postictal seizure inhibition in amygdaloid-kindled cats

A recycling trial consisting of six amygdaloid stimuli at 60-min intervals was applied to evaluate postictal seizure inhibition (PSI). Cats kindled unilaterally and bilaterally from the amygdala were used. The results obtained may be summarized as follows: (1) kindled generalized convulsions resulted in three consecutive postictal stages before recovery from postictal behavioral depression; (2) in bilaterally kindled cats, PSI lasted for 3-4 h, which was longer than the postictal behavioral depression; (3) no correlation was found between interictal spike frequency and decreased susceptibility to convulsion during PSI; (4) the duration of PSI was prolonged significantly after secondary site amygdaloid kindling; and (5) such changes were observed greater than 2 weeks after the last secondary site stimulation. It is suggested that the intensity of PSI is altered by the establishment of secondary epileptogenesis in the contralateral hemisphere, which exerts a long-lasting seizure inhibitory effect on the primary epileptogenic focus.

[Anticonvulsant effects of TRH analog. 3. Prophylactive effects of DN-1417 on kindling model]

We reported previously that TRH . T and a novel TRH analog, DN-1417 had anticonvulsant effects in kindling cat preparations which had been established as an experimental model of epilepsy. Although acute anticonvulsant effect of DN-1417 was short-lasting without dose-related efficacy, DN-1417 administration resulted a lasting increase in convulsive threshold in some cases. In order to study the effects of DN-1417 on kindling seizure development (prophylactic effect), 10 amygdaloid kindling cats were examined. The animals in the DN-1417 group (N = 4) were treated with the agent (1 mg/kg) prior to each daily kindling stimulation for 35 days (drug sessions). Six cats in control group were kindled without drug treatment. Kindling rates, changes in after-discharge duration, and positivity of transference phenomenon to contralateral amygdala were compared between these two groups. The results obtained were: 1) Positive prophylactic effects on kindling was found in 3 cats of DN-1417 group. In these cats, 19 (7-37) additional daily stimulation to those given during the drug session were required for the kindling. 2) No positive transfer to contralateral amygdala was found in 2 of 3 cats of DN-1417 group. 3) During the drug sessions, self-sustained afterdischarges were fragmented into separated bursts of discharges with short duration in 2 cats of DN-1417 group. These results suggested that DN-1417 may prevent a trans-synaptic change underlying the kindling, which might relate to the long-lasting anticonvulsant effect reported clinically. A possible mechanism underlying the prophylactic effects of DN-1417 was discussed.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of callosal bi-section on temporal cortical seizure and postictal refractory period in kindled cats]

Effects of midline bi-section including corpus callosum and hippocampal commissure on the kindled generalized convulsion and postictal refractory period (PRP) were examined in temporal cortical kindled cats. Time latency for re-appearance of generalized convulsion after the initial generalized convulsion was designated as a PRP arbitrarily in this experiment. Six repeated electrical stimulation at afterdischarge threshold intensity with one hour interval was performed, and EEG was recorded during PRP test session. Following results were obtained: 1) Kindled generalized convulsion in the split brain cats was characterized by asymmetrical or hemi-convulsion with lateralized afterdischarge in the stimulated hemisphere, 2) EEG silence and monorhythmic 2.5-3 cps high voltage slow activity in the split brain cats did not differ, rather prolonged than the control group in duration, but such postictal EEG changes were lateralized only in the stimulated hemisphere. Behavioral suppression was reduced markedly by midline bi-section, as compared with intact control, 3) In the PRP session of the split brain cats, the initially induced hemi-convulsion appeared with lateralized active afterdischarge lasting for 76.8 sec in the stimulated hemisphere. It was followed by the postictal EEG change as mentioned above in the stimulated hemisphere. In spite of such full-blown ictal events in the stimulated hemisphere, PRP was shorter (within 2 hrs) in the split brain cats than the control cats (more than 4 hrs). It is concluded that midline bi-section including corpus callosum and hippocampal commissure not only modify the pattern and duration of kindled generalized convulsion, but markedly reduce a seizure intensity reflected by shortening of postictal behavioral suppression and PRP.