Earlier BMI rebound and lower pre-rebound BMI as risk of obesity among Japanese preschool children.

OBJECTIVES: Longitudinal growth data of children were analyzed to clarify the relationship between the timing of body mass index (BMI) rebound and obesity risk in later ages. SUBJECTS/METHODS: Of 54 558 children born between April 2004 and March 2005 and longitudinally measured in April and October every year in the preschool period, 15 255 children were analyzed wherein no longitudinal measurement is missing after 1 year of age. BMI rebound age was determined as the age with smallest BMI value across longitudinal individual data after 1 year of age. Rebound age was compared between overweight and non-overweight groups. The subjects were divided into groups based on the timing of rebound. The sex- and age-adjusted mean of the BMI, height and weight s.d. scores for age group, along with 6 months weight and height gain, were compared among groups using analysis of covariance. RESULTS: Among those who were overweight at 66-71 months of age, BMI rebound age obtained at approximately 3 years of age was compared with the non-overweight group, whose BMI rebound age was utmost 66 months or later (P<0.001). The comparison among BMI age group showed that earlier BMI rebound results in larger BMI (P<0.001) and larger weight and height gain after the rebound (P<0.001). Among the group with BMI rebound earlier than 30 months of age, low BMI was observed (P<0.001). Slight elevation of height and weight gain was observed before the BMI rebound among groups with rebound age earlier than 60 months of age (P<0.001). CONCLUSION: Earlier BMI rebound timing with pre-rebound low BMI leads to greater childhood obesity risk; hence, early detection and prevention is necessary for such cases.

Longitudinal changes in body mass index of children affected by the Great East Japan Earthquake.

BACKGROUND: The evacuation and disruption in housing caused by the 2011 Great East Japan Earthquake and following nuclear radiation may have influenced child health in many respects. However, studies regarding longitudinal childhood growth are limited. Therefore, in this study we aimed to explore the influence of the earthquake on longitudinal changes in body mass index in preschool children. METHODS: Participants were children from nursery schools who cooperated with the study in the Iwate, Miyagi and Fukushima prefectures. The exposed group consisted of children who experienced the earthquake during their preschool-age period (4-5 years old). The historical control group included children who were born 2 years earlier than the exposed children in the same prefectures. Trajectories regarding body mass index and prevalence of overweight/obesity were compared between the two groups using multilevel analysis. Differences in the changes in BMI between before and after the earthquake, and proportion of overweight/obesity was compared between the two groups. We also conducted subgroup analysis by defining children with specific personal disaster experiences within the exposed group. RESULTS: A total of 9722 children were included in the study. Children in the exposed group had higher body mass indices and a higher proportion of overweight after the earthquake than the control group. These differences were more obvious when confined to exposed children with specific personal disaster experiences. CONCLUSIONS: Children's growth and development-related health issues such as increased BMI after natural disasters should evoke great attention.

Incidence and prevalence of childhood-onset Type 1 diabetes in Japan: the T1D study.

AIMS: A majority of children with Type 1 diabetes in Japan are registered with the government-subsidized Specified Pediatric Chronic Disease Treatment Research Projects (SPCDTRP). In this study, the incidence and prevalence of childhood-onset (< 15 years) Type 1 diabetes in Japan were estimated by drawing on SPCDTRP data. METHODS: Data available for 2005-2012 from the SPCDTRP and Statistics Bureau, Ministry of Internal Affairs and Communications were used to estimate the incidence of Type 1 diabetes for 2005-2010, adjusted to cover those registered within 3 years of disease onset and stratified by sex, age at onset and period of onset. RESULTS: The incidence of Type 1 diabetes for 2005-2010 was 2.25/100,000 persons [95% confidence intervals (95% CI), 2.14-2.36] (boys: 1.91, 95% CI, 1.83-1.98; girls: 2.52, 95% CI, 2.34-2.69), with that for the age brackets 0-4, 5-9 and 10-14 years being 1.48 (95% CI, 1.29-1.66), 2.27 (95% CI, 2.08-2.47) and 3.00 (95% CI, 2.74-3.25), respectively. The onset of disease was shown to peak at age 13 among boys (3.28, 95% CI, 3.02-3.55) and at age 10 among girls (3.28, 95% CI, 3.02-3.55). The peak periods of disease onset were April/May and December. The number of children aged < 15 years with Type 1 diabetes for 2005-2012 was estimated to be 2326 (95% CI, 2202-2450) with the prevalence estimated as 13.53/100,000 persons (95% CI, 12.63-14.43). CONCLUSIONS: Study findings demonstrated no increase in the incidence of Type 1 diabetes, although suggesting, in agreement with earlier reports, that the onset of disease peaks in adolescence with a female predominance. In addition, the incidence of childhood-onset diabetes exhibited an annual bimodal pattern in this study.

Mandibular reconstruction using a poly(L-lactide) mesh combined with autogenous particulate cancellous bone and marrow: a prospective clinical study.

The purpose of this study was to evaluate the stability and viability of mandibular bone regeneration using a poly(L-lactide) (PLLA) mesh and autogenous particulate cancellous bone and marrow (PCBM). Sixty-two procedures were undertaken at eight hospitals (22 malignant tumours, 30 benign tumours, five cysts, two osteomyelitis, two trauma, and one atrophy of the alveolar ridge); the success rate was 84%. The follow-up period was between 9 and 200 months (mean 88.2 months). Consequently, bone regeneration at 6 months postoperation was excellent in 35 cases (57%), good in 17 cases (27%), and poor in 10 cases (16%). In six of the 'poor' cases, the PLLA mesh was removed due to local infection early after surgery. Bone resorption>20% was observed in only one of 46 cases with a follow-up term of >1 year. There were no signs of any other adverse effects except in one case where a section of the tray broke off late in the follow-up period. It is concluded that this method is stable and effective due to favourable morphological and functional recovery and low invasiveness. It may thus be a useful alternative procedure for mandibular reconstruction.

Comparison of the expression patterns of two LIM-homeodomain genes, Lhx6 and L3/Lhx8, in the developing palate.

OBJECTIVES: To compare and contrast the gene expression of two LIM-homeobox type transcription factors, Lhx6 and L3/Lhx8, in secondary palate formation. METHODS: In situ hybridization histochemistry with digoxygenin (DIG) labelled cRNA probes specific for Lhx6 and L3/Lhx8. MATERIALS: Serial cryo-sections of embryonic day (E)13.5, 14.5, and 15.5 mice (C57BL/6). OUTCOME MEASURE: Comparison of the signal intensities of NBT/BCIP precipitate by alkaline phosphatase conjugated anti-DIG antibody. RESULTS: From E13.5 to E15.5, Lhx6 and L3/Lhx8 signals are detected in palatal mesenchyme, but the L3/Lhx8 signal is much more intense than the Lhx6 signal. In palatal epithelium, covering the mesenchyme, Lhx6 mRNA is transiently expressed at E14.5, while L3/Lhx8 mRNA expression is never detected throughout the development. CONCLUSION: Lhx6 and L3/Lhx8 functions may be partially redundant in the mesenchyme of the secondary palate, but not in the palatal epithelium.

Expression of the novel transcription factor OASIS, which belongs to the CREB/ATF family, in mouse embryo with special reference to bone development.

The OASIS gene, which encodes a novel CREB/ATF family member, was isolated from long-term cultured astrocytes that were employed as an in vitro gliosis model. In the present study, we examined the expression pattern of the OASIS gene in the developing mouse embryo by in situ hybridization histochemistry and compared it with the expression of osteogenesis markers. OASIS mRNA expression was most strongly detected in preosteoblasts of the outer bony cortex of the ribs. Alveolar bone also showed strong signals for OASIS gene expression. OASIS mRNA was also localized to the preodontoblast of tooth buds. Expression began at embryonic day 12 (D12.5), peaked around D14.5-16.5, and continued to D18.5. The pattern of expression was very similar to that of hXBP-1 mRNA, which encodes another CREB/ATF family member. Spatiotemporal patterns of OASIS partly overlapped that of osteopontin, osteonectin, and alpha1 type I procollagen genes. Among these, the time course of OASIS mRNA expression was most similar to that of osteopontin mRNA expression, suggesting that the OASIS protein is involved in the late phase of osteoblast differentiation, as compared to the Cbfa1 that regulates early phases of osteoblast differentiation.

New compound heterozygous mutation in the CYP17 gene in a 46,XY girl with 17 alpha-hydroxylase/17,20-lyase deficiency.

BACKGROUND: 17alpha-Hydroxylase/17,20-lyase deficiency is caused by a defect of P450c17 which catalyzes both 17alpha-hydroxylase and 17,20-lyase reactions in adrenal glands and gonads. RESULTS: In the present study, we analyzed the CYP17 gene in a Japanese patient with 17alpha-hydroxylase/17,20-lyase deficiency. The patient was a phenotypic girl and referred to us for right-sided inguinal hernia at the age of 4 years. Biopsy of the herniated gonad showed testicular tissue. The karyotype was 46,XY. At 6 years of age, hypertension was clearly recognized and the patient was diagnosed as having 17alpha-hydroxylase/17,20-lyase deficiency based on the clinical and laboratory findings. Analysis of the CYP17 gene revealed a compound heterozygous mutation. One mutation was an undescribed single nucleotide deletion at codon 247 in exon 4 (CTT to CT: 247delT) and the other was a missense mutation resulting in a substitution of His to Leu at codon 373 in exon 6 (CAC to CTC: H373L), which has been previously shown to abolish both 17alpha-hydroxylase and 17,20-lyase activities. The functional expression study of the 247delT mutant showed that this 247delT mutation completely eliminates both 17alpha-hydroxylase and 17,20-lyase activities. CONCLUSIONS: Together, these results indicate that the patient is a compound heterozygote for the mutation of the CYP17 gene (247delT and H373L) and that these mutations inactivate both 17alpha-hydroxylase and 17,20-lyase activities and give rise to clinically manifest 17alpha-hydroxylase/17,20-lyase deficiency.

Two hyperandrogenic adolescent girls with congenital portosystemic shunt.

UNLABELLED: We describe two adolescent girls with a congenital portosystemic shunt who exhibited hyperandrogenism in addition to insulin resistant hyperinsulinaemia. Case 1 was referred to our clinic to undergo a routine clinical work-up prior to tonsillectomy at 14 years of age. Mild liver dysfunction was identified and hypogenesis of the portal vein with a congenital portosystemic shunt diagnosed. Primary amenorrhoea and virilization were evident and an endocrinological evaluation revealed hyperandrogenism and insulin resistant hyperinsulinaemia. Case 2 was referred at 15 years of age because of cardiomegaly. Mild liver dysfunction and hyperbilirubinaemia led to a diagnosis of agenesis of the portal vein with a congenital portosystemic shunt. Virilization was evident and an endocrinological evaluation revealed hyperandrogenism and insulin resistant hyperinsulinaemia. The haemodynamics of these patients were similar to those of secondary portosystemic shunt due to liver cirrhosis, which is often associated with hyperinsulinaemia and/or non-insulin dependent diabetes mellitus. On the other hand, hyperandrogenism is associated with certain insulin-resistant conditions with hyperinsulinaemia, including the polycystic ovary syndrome (PCO). Hyperinsulinaemia is believed to cause hyperandrogenism in patients with PCO by stimulating androgen production in both the ovary and adrenal gland. Therefore, in congenital portosystemic shunts, hyperinsulinaemia is also thought to cause hyperandrogenism due to the same mechanism. CONCLUSION: A certain percentage of female patients with hyperandrogenism, likely including those with polycystic ovary syndrome may also have congenital portosystemic shunts. Our results indicate that serum levels of total bile acids and ammonia are prognostic indicators of this hepatic vascular anomaly.

Anti-tumor immunity against CT26 colon tumor in mice immunized with plasmid DNA encoding beta-galactosidase fused to an envelope protein of endogenous retrovirus.

Endogenous retroviral gene products have been recognized as being expressed in human cancerous tissues. However, these products have not been shown to be antigenic targets for T-cells, possibly due to immune tolerance. Since carcinogen-induced colon tumor CT26 expresses an envelope protein, gp70, of an endogenous ecotropic murine leukemia virus that is comparable to human tumor-associated antigens, we examined whether a DNA vaccine containing the gp70 gene induces protective immunity against CT26 cells. Injection of mice with plasmid DNA (pDNA) encoding gp70 alone failed to induce anti-gp70 antibody (Ab) or anti-CT26 cytotoxic T lymphocyte (CTL) responses. However, immunization with pDNA encoding the beta-galactosidase (beta-gal)/gp70 fusion protein induced anti-gp70 Ab and anti-CT26 CTL responses and conferred protective immunity against CT26 cells. These results indicate that beta-gal acts as an immunogenic carrier protein that helps in the induction of immune responses against the poorly immunogenic gp70. Considering these results, it is possible that potential tolerance to the endogenous retroviral gene products expressed by human tumors may be overcome by DNA vaccines that contain an endogenous retroviral gene fused to genes encoding immunogenic carrier proteins.

Clinical and molecular studies in 15 females with ring X chromosomes: implications for r(X) formation and mental development.

We report clinical and molecular findings in 15 Japanese mosaic females with r(X) chromosomes, 45,X/46,X,r(X), confirmed by fluorescence in situ hybridization (FISH) analysis for DXZ1 and whole X chromosome painting. Cases 1-3, 5-7, and 11-13 had mental retardation (MR), the remaining cases being free from MR. FISH analysis showed that XIST was absent from the r(X) chromosomes in cases 1-4 and was present on the r(X) chromosomes in cases 5-15. X-inactivation analysis for the methylation status of the AR gene indicated that, of eight cases with XIST-positive r(X) chromosomes in more than 10% (23%-62%) of lymphocytes (cases 5-12), cases 5-10 had selective X-inactivation, whereas cases 11 and 12 had active X disomy. Microsatellite analysis for multiple loci on the pericentromeric region revealed that, of 11 cases with r(X) chromosomes in more than 10% (13%-62%) of lymphocytes (cases 1, 2, and 4-12), cases 1, 2, and 5-10 had heterozygous alleles for at least one locus, whereas cases 4, 11, and 12 had single alleles for all the loci examined. The results suggest that the r(X) and normal X chromosomes could be of biparental or uniparental origin, and that mental status in females with r(X) chromosomes is determined by multiple factors, including the presence or absence of XIST on the r(X) chromosomes and the size and frequency of active r(X) chromosomes, in addition to co-incidental genetic and environmental factors.

A novel missense mutation of mineralocorticoid receptor gene in one Japanese family with a renal form of pseudohypoaldosteronism type 1.

Pseudohypoaldosteronism type 1 (PHA1) is a rare condition characterized by neonatal salt loss with dehydration, hypotension, hyperkalemia, and metabolic acidosis, despite elevated plasma aldosterone levels and PRA. Two modes of inheritance of PHA1 have been described: an autosomal dominant form and an autosomal recessive form. An autosomal recessive form manifests severe life-long salt wasting resulting from multiple mineralocorticoid target tissue such as sweat, salivary glands, the colonic epithelium, and lung. Contrary, an autosomal dominant PHA1 manifests milder salt wasting that gradually improves with advancing age. Recently, in one sporadic and four dominant cases, four different mutations including two frame shift mutations, two premature termination codons, and one splice site mutation in the mineralocorticoid receptor (MR) gene were identified. We studied the molecular mechanisms of one Japanese family with a renal form of PHA1. PCR and direct sequencing of the MR gene identified a heterozygous point mutation changing codon 924 Leu (CTG) to CCG (Pro) (L924P) in all affected members. COS-1 cells were transfected with expression vectors for either wild type or the mutant MR-L924P receptors, together with the reporter plasmid (glucocorticoid response element tk-CAT). Aldosterone increased CAT activity in cells expressing wild-type receptor, but had no effect in cells expressing the mutant receptors. These results suggest that mineralocorticoid resistance in this family is due to a missense mutation in the MR gene. To our knowledge, this is the first case of the missense mutation of the MR gene in renal PHA1.

Skeletal features and growth patterns in 14 patients with haploinsufficiency of SHOX: implications for the development of Turner syndrome.

We report on clinical features in 14 Japanese patients (4 males and 10 females) with partial monosomy of the short arm pseudoautosomal region involving SHOX (n = 11) or total monosomy of the pseudoautosomal region with no involvement of disease genes on the sex-differential regions (n = 3). Skeletal assessment showed that three patients had no discernible skeletal abnormalities, one patient exhibited short 4th metacarpals and borderline cubitus valgus, and the remaining 10 patients had Madelung deformity and/or mesomelia characteristic of Léri-Weill dyschondrosteosis (LWD), together with short 4th metacarpals and/or cubitus valgus. Skeletal lesions were more severe in females and became obvious with age. Growth evaluation revealed that patients without LWD grew along by the -2 SD growth curve before puberty and showed a normal or exaggerated pubertal growth spurt, whereas those with LWD grew along by the standard growth curves before puberty but exhibited an attenuated pubertal growth spurt and resultant short stature. Maturational assessment indicated a tendency of relatively early maturation in patients with LWD. There was no correlation between the clinical phenotype and the deletion size. These findings suggest that haploinsufficiency of SHOX causes not only short stature but also Turner skeletal anomalies (such as short 4th metacarpals, cubitus valgus, and LWD) and that growth pattern is primarily dependent on the presence or absence of LWD. Because skeletal lesions have occurred in a female-dominant and age-influenced fashion, it is inferred that estrogens exert a maturational effect on skeletal tissues that are susceptible to premature fusion of growth plates because of haploinsufficiency of SHOX, facilitating the development of skeletal lesions.

Pharmacokinetics and metabolic effects of high-dose growth hormone administration in healthy adult men.

To evaluate pharmacokinetics of growth hormone (GH) and its effects on IGF-I, glucose, insulin, nonesterified fatty acid (NEFA) and triglyceride (TG), fifteen Japanese healthy adult male volunteers (20-27 years old) were studied. The subjects were divided into three groups, and received with a single s.c. injection of 0.075, 0.15 and 0.30 IU/kg of GH, respectively. The subjects assigned to receive 0.30 IU/kg were administered for additional 6 days. After a single administration of GH, Cmax and AUC of GH were increased in a dose-dependent manner. There was a significant positive correlation between the AUC and the T1/2 (r=0.516, P<0.05). Total body clearance was significantly greater in 0.075 IU/kg group than the other groups and showed a significant negative correlation with Cmax (r=-0.694, P<0.005) and AUC (r=-0.723, P<0.005). After a single administration of each dose, serum IGF-I concentrations were increased gradually. In the repeated administered group (0.30 IU/kg), IGF-I concentrations almost reached a plateau at a significantly high level four days after the start of administration and remained at a high level (786-405.4 ng/ml) until day 8. There was no significant difference in diurnal change of blood glucose and serum insulin after a single administration of GH among three groups. In the 0.3 U/kg group, there was no significant difference in diurnal change of blood glucose between day 1 and day 7, but serum insulin level was significantly higher in day 7 than in day 1 (P<0.01). Serum concentrations of NEFA were increased over time after administration in all subjects administered once or repeatedly. TG concentrations showed no changes after single administration of each dose level, but were significantly increased on day 7 in the subjects repeatedly treated with 0.30 IU/kg/day. This effect is speculated to be caused by high dose GH treatment. The above findings demonstrated that higher GH dose significantly influences on carbohydrate and lipid metabolism. It remains necessary to elucidate what kinds of effects of the long-lasting increased levels of insulin and triglyceride, even if reversible, would have on glucose and lipid metabolism.

Localization of huntingtin-interacting protein-2 (Hip-2) mRNA in the developing mouse brain.

Huntingtin-interacting protein-2 (Hip-2) was identified as a human protein specifically associated with huntingtin in vitro, a gene product affected in patients with Huntington disease (HD). It is a ubiquitin-conjugating enzyme identical to the previously characterized bovine E2-25k. We identified the mouse Hip-2 homologue (mHip-2) and examined its distribution patterns in the developing mouse brain in order to gain an insight into the functional significance of the Hip-2 protein in the normal brain as well as in the pathogenesis of HD. As reported with huntingtin, the mHip-2 mRNA expression developed in parallel with neuronal maturation and became distributed widely in the postnatal mouse brain. This spatiotemporal pattern of mHip-2 mRNA expression resembled that of huntingtin. We further demonstrated that mHip-2 mRNA was colocalized with huntingtin-like immunoreactivity in a single neuron. These findings suggested that the Hip-2 interacted with huntingtin in vivo and played an important role in HD pathogenesis.

Expression of sonic hedgehog signal transducers, patched and smoothened, in human basal cell carcinoma.

In basal cell nevus syndrome (BCNS) patients, mutations of a gene, patched (ptc), which encodes a putative signal transducer of sonic hedgehog protein (SHH), were found and are thought to be one of the major causes of BCNS. The SHH signaling pathway is an important developmental pathway, and ptc protein (PTC) is a suppressive component serving as a receptor for the secreted SHH. Another transmembrane protein, smoothened (SMO), forms a complex with PTC and regulates this signaling pathway. Recent transgenic studies have strengthened the importance of the SHH signaling system in the etiology of basal cell carcinoma (BCC). In this study, we examined the expression patterns of mRNA for ptc and smo in two different BCC subtypes and normal skin. We found that the expressions of ptc and smo mRNA were enhanced in the tumor nests of the nodular BCC, especially at the advancing portions, but were under the detectable level in the superficial BCC cases examined, indicating that ptc and smo mRNA expressions might be associated with BCC tumor progression and divide the BCC histologic types into two subtypes, superficial and nodular types. In addition, no obvious signals for ptc and smo mRNA were detected in the normal human epidermis, appendages, or seborrheic keratosis, indicating that the abnormal proliferation of follicular epithelial cells caused by ptc, smo and/or other genetic changes, which also cause ptc and smo overexpressions, might result in BCC tumor formation.

Identification of a novel gene, OASIS, which encodes for a putative CREB/ATF family transcription factor in the long-term cultured astrocytes and gliotic tissue.

Gliosis is a characteristic response of astrocytes to inflammation and trauma of the central nervous system (CNS). To study the mechanisms underlying gliosis, we performed differential display screening for genes specifically induced in long-term cultured astrocytes used as an in vitro gliosis model. We identified and characterized a gene (named OASIS, for old astrocyte specifically-induced substance) expressed in long-term cultured mouse astrocytes, or 'old astrocytes (OA)'. The OASIS gene encoded a putative transcription factor belonging to the cyclic AMP responsive element binding protein/activating transcription factor (CREB/ATF) gene family, with homology to box B-binding factor-2 (BBF-2), a Drosophila transcription factor. Its expression was developmentally regulated; OASIS mRNA was primarily expressed in the salivary gland and cartilage in the mouse embryo and it was transiently upregulated in the brain during postnatal two weeks. The expression became weaker in the adult brain. We also demonstrated that an expression of the OASIS mRNA was induced in response to the cryo-injury of the mouse cerebral cortex. The distribution pattern of the OASIS-positive cells in the injured cortex was very similar to that of the glial fibrillary acidic protein (GFAP)-positive cells. These results suggest that OASIS protein may play a role in gliotic events.

Recent status in the occurrence of leukemia in growth hormone-treated patients in Japan. GH Treatment Study Committee of the Foundation for Growth Science, Japan.

The Foundation for Growth Science in Japan has monitored the safety and efficacy of GH treatment in GH-deficient patients since 1975. Data were collected from more than 32,000 patients up to December 31, 1997. New leukemia was observed in 14 patients and myelodysplastic syndrome (MDS) in one patient. The types of leukemia were acute lymphocytic leukemia (n = 6; 40%), acute myelocytic leukemia or MDS (n = 7; 47%), and chronic myelocytic leukemia (n = 2; 13%). Leukemia developed in 9 patients during GH treatment and in 6 after the cessation of GH treatment. Six patients had known risk factors for leukemia, such as Fanconi's anemia and previous radiation or chemotherapy. Patient-years of GH therapy was defined as the time from the first dose of GH to the date of the last visit during GH therapy, and patient-years of risk was defined as the time from the first dose of GH to December 31, 1997. The incidence of leukemia of patient-years of GH therapy and patient-years of risk in GH-treated patients without risk factors was 3.0/100,000 and 3.9/100,000, respectively, a figure similar to the incidence in the general population aged 0-15 yr. We conclude that the incidence of leukemia in GH-treated patients without risk factors is not greater than that in the general population aged 0-15 yr, and a possible increased occurrence of leukemia with GH treatment appears to be limited to patients with risk factors.

Eos: a novel member of the Ikaros gene family expressed predominantly in the developing nervous system.

We identified a novel member of the Ikaros gene family, which has critical roles in the development of lymphoid lineages. This gene, which we named Eos, was expressed predominantly in the developing central and peripheral nervous system. Eos protein could interact with itself and Ikaros protein through its C-terminal portion in the yeast two hybrid assay. These findings suggested that Eos may have important roles in neural development similarly to the Ikaros family in the development of hemolymphoid tissue.

High-dose growth hormone (GH) treatment in prepubertal GH-deficient children.

Two clinical studies were conducted to determine the effect of different doses of growth hormone (GH) on prepubertal growth in GH-deficient boys. In one study, GH doses of 1.0 and 1.5 IU/kg/week (0.33 and 0.5 mg/kg/week) were given to groups of five children and compared with a conventional Japanese dose of 0.5 IU/kg/week (0.17 mg/kg/week) in 15 children. A significant dose-dependent increase in height velocity occurred in the first year of treatment, but differences between doses were not significant thereafter. In a second study, GH was administered to ten boys at a dose of 0.5 IU/kg/week for the first year, 0.75 IU/kg/week for the second year, 1.0 IU/kg/week for the third year and 0.5 IU/kg/week for the fourth and subsequent years (0.17, 0.25, 0.33 and 0.17 mg/kg/week, respectively). During the second and third years of GH treatment, these boys had significantly higher growth rates than controls, who were given GH at 0.5 IU/kg/week (0.17 mg/kg/week) throughout, indicating successful reduction in 'waning' of the treatment effect. At the end of the fourth year, the different protocols from the two studies had both resulted in a greater height SDS than the controls, and did not advance bone maturation. In conclusion, these protocols may be effective in increasing prepubertal height gain in children with GH deficiency.

Serum levels of 20-kilodalton human growth hormone (GH) are parallel those of 22-kilodalton human GH in normal and short children.

Twenty-kilodalton human GH (20K), which is one of the human GH (hGH) variants, is thought to be produced by alternative premessenger ribonucleic acid splicing. However, its physiological role is still unclear due to the lack of a specific assay. We have measured serum 20K and 22-kDa hGH (22K) by specific ELISAs to investigate the physiological role of 20K in children. The subjects were 162 normal children, aged 1 month to 20 yr; 12 patients with GH deficiency (GHD), aged 11 months to 13 yr; 57 children with non-GHD short stature, aged 2-17 yr; and 13 girls with Turner's syndrome, aged 5 months to 15 yr. Samples were collected at random from normal children and were collected after hGH provocative tests and 3-h nocturnal sleep from GHD, non-GHD short stature, and Turner's syndrome children. The mean basal serum concentrations of 22K and 20K were 2.4 +/- 2.8 ng/mL and 152.3 +/- 184.0 pg/mL in normal boys and 2.5 +/- 3.1 ng/mL and 130.6 +/- 171.5 pg/mL in normal girls, respectively. The percentages of 20K (%20K) were 5.8 +/- 2.1% and 6.0 +/- 3.2% in 83 normal boys and 79 normal girls, respectively. There was no significant difference in %20K either among ages or between the prepubertal stage and the pubertal stage in normal boys and girls. The mean %20K values in basal samples of provocative tests in 12 patients with GHD, non-GHD short stature, and Turner's syndrome were 6.5 +/- 2.4%, 6.5 +/- 3.8%, and 5.9 +/- 3.2%, respectively. There was no significant difference in %20K among normal children and these growth disorders, and there was no significant difference in %20K throughout the hGH provocative tests and 3-h nocturnal sleep in these growth disorders. There was also no significant correlation between the percentage of 20K and the height SD score or body mass index in either normal children or subjects with these growth disorders. In conclusion, the %20K is constant, regardless of age, sex, puberty, height SD score, body mass index, and GH secretion status. The regulation of serum 20K levels remains to be established.