Aromatase inhibitors: a useful additional therapeutic option for slowing down advanced bone age in boys with growth hormone deficiency.

INTRODUCTION: Aromatase inhibitors (AIs) have been used to slow down estrogen-dependent skeletal maturation in pubertal boys with short stature. In the literature, few data evaluate the effectiveness and safety of AIs in boys with growth hormone deficiency (GHD). This study aimed to evaluate the auxologic effects and short-term laboratory profiles of combined AI and rhGH therapy for 1 year in adolescent males with GHD. SUBJECTS AND METHODS: Male subjects between the ages of 10 and 16 with GHD from two different centers were included in the study. Patients were divided into two groups: (i) those who only used recombinant human growth hormone (rhGH) therapy (Group I; G-I) and (ii) those who also used AI therapy (anastrozole or letrozole) along with rhGH (Group II; G-II). RESULTS: Forty-one patients (G-I, 46%; G-II, 54%) were included in the study. All the subjects had isolated GHD. At the beginning of the treatment, the chronological ages (CAs) of the patients in the G-I and G-II groups were 11.8 (10.9-13.7) and 12.8 (12.0-14.3) years, respectively. The ratios of bone age (BA)/CA for the two groups were 0.8 (0.8-0.9) and 1.0 (0.9-1.1), respectively (p < 0.001). After the treatment, the height standard deviation (SD) scores and predicted adult height (PAH) significantly increased from baseline in all subjects in the G-I and G-II groups (p < 0.001; p < 0.001, respectively). There was no significant change in the ratio of BA/CA post-therapy in the G-I group (p = 0.1), while there was a significant decrease in the G-II group (p < 0.001). The growth velocities of the patients in the G-I and G-II groups were 9.1 (7.4-10.1) cm/year [1.5 (0.8-5.0) SD score] and 8.7 (7.5-9.9) cm/year [1.1 (0.3-3.1) SD score], respectively (p = 0.6). While post-therapy serum testosterone concentrations were seen to increase in the G-II group, none of the patients exhibited hematocrit above 50 percent, and the fasting glucose concentrations were normal. CONCLUSIONS: When used in addition to rhGH therapy in boys with GHD and advanced BA, AIs were observed to slow down the tempo of BA maturation after 1 year, compared to those who received rhGH treatment alone. AI therapy was found to be safe during the 1-year observation period and thus could be considered for preserving growth potential in these patients.

Comparison of the effects of the L-dopa and insulin tolerance tests on cortisol secretion.

PURPOSE: The aims of the present study are to evaluate the effect of L-dopa on the secretion of cortisol and adrenocorticotropic hormone (ACTH) in short children and compare the performance of this test with the insulin tolerance test (ITT) in a large number of patients. METHODS: A total of 29 short but otherwise healthy children [mean age 9.5 ± 3.1 years (range 3.7-14.9 years)] who had inadequate growth hormone (GH) responses to ITT, which was performed as the first test, were consecutively enrolled in this study. GH, cortisol, and ACTH levels were measured just before administration of L-dopa and then at 30-min intervals afterward over a total time of 120 min. Peak concentrations of cortisol and ACTH exceeding 18 µg/dL (496 mmol/L) and 46 pg/mL (10.2 pmol/L), respectively, were defined as an adequate response. RESULTS: While the L-dopa test revealed that 26 of the 29 children (89.7%) had peak serum cortisol levels of > 18 µg/dL, the ITT revealed that only 23 children (79.3%) had adequate cortisol responses. The L-dopa test revealed normal ACTH responses (> 46 pg/mL) in 24 (82.8%) patients. Peak cortisol levels were higher in children with normal ACTH responses than in those with subnormal ACTH responses (25.6 ± 6.2 vs. 19.5 ± 6.4 µg/dL, p = 0.054), but the difference observed was statistically insignificant. CONCLUSION: The results of the current study confirm that the L-dopa test is a reliable test of cortisol secretion. As such, this test may be applicable to assessments of the hypothalamic-pituitary-adrenal axis.

A novel mutation in steroidogenic factor (SF1/NR5A1) gene in a patient with 46 XY DSD without adrenal insufficiency.

Steroidogenic factor-1 (SF-1), also known as nuclear receptor subfamily 5 group A member 1 (NR5A1), is a member of orphan receptor subfamily and located on chromosome 9 (9q33). In 46, XY individuals with mutation of SF-1 gene, adrenal failure, testis dysgenesis, androgen synthesis defects, hypospadias and anorchia with microphallus, infertility can occur from severe to mild. We report a case of a 20-day-old male who is admitted to our clinic due to ambiguous genitalia. In this report, we describe a novel heterozygous c.814A > C (p. T272P) NR5A1 mutation in a patient with 46, XY DSD without adrenal insufficiency. We describe a novel missense mutation c.814A > C (p. T272P) in NR5A1 gene which had not previously been reported. Also this report highlights that the potential diagnostic utility of next-generation sequencing is an effective strategy versus Sanger sequencing to identify genetic mosaicism in clinical practice.

Association Between Vitamin D Receptor Polymorphism and Familial Mediterranean Fever Disease in Turkish Children.

Familial Mediterranean fever (FMF) is an autosomal recessive, inherited autoinflammatory disease characterized by recurrent, self-limited attacks of fever, and inflammation of serosal surfaces. The aim of our study was to determine a possible relationship between Vitamin D receptor (VDR) gene polymorphisms and the risk of children with FMF. We investigated VDR FokI (rs10735810), TaqI (rs731236), BsmI (rs1544410), and ApaI (rs7975232) polymorphisms in 50 children with FMF and 150 age-matched healthy control subjects. This study was performed by polymerase chain reaction-based restriction fragment length polymorphism. There was no significant difference between patients and controls for VDR FokI, TaqI, BsmI, and ApaI genotypes and alleles (p > 0.05). Results need to be supported by further investigations that define haplotype patterns for VDR gene polymorphisms in a larger group and different ethnic groups of FMF patients.

Serum nesfatin-1 and leptin levels in non-obese girls with premature thelarche.

AIM: We aimed to investigate serum nesfatin-1 level in girls with premature thelarche (PT) and its relationship with anthropometric parameters and leptin, which are involved in the initiation of pubertal process. SUBJECTS-METHODS: Non-obese girls who presented with the complaint of early (2-8 years) and isolated breast development were included in the study. The control group consisted of age-matched healthy prepubertal girls. Auxological measurements were performed in all subjects. Gonadotropin-releasing hormone (GnRH) stimulation test and bone age assessment were conducted in subjects with early breast development. Girls with a bone age/chronologic age ratio <1.2 and a peak luteinizing hormone (LH) response to GnRH stimulation <5 mIU/L were included in the PT group. RESULTS: The study included 22 non-obese girls with PT and 24 healthy prepubertal controls. Body mass index (BMI), BMI-standard deviation score (SDS) and height SDS were similar between the groups (p > 0.05). Serum leptin and nesfatin-1 levels were found significantly higher in the PT group compared to controls (p < 0.05). No correlation was detected between nesfatin-1 and basal LH, basal follicle stimulating hormone (FSH), stimulated peak LH, peak FSH, leptin levels and anthropometric parameters in the PT group (p > 0.05). CONCLUSION: Results of the present study showed that serum nesfatin-1 and leptin levels are significantly higher in girls with PT than in prepubertal controls. This finding suggests that similar to leptin, nesfatin-1 may also have a central or peripheral role in the initiation of pubertal process and may be related to PT pathogenesis.

The muscle regulatory gene, Myf-6, has a biphasic pattern of expression during early mouse development.

The spatial and temporal expression pattern of the muscle regulatory gene Myf-6 (MRF4/herculin) has been investigated by in situ hybridization during embryonic and fetal mouse development. Here, we report that the Myf-6 gene shows a biphasic pattern of expression. Myf-6 transcripts are first detected in the most rostral somites of the mouse embryo at 9 d of gestation and accumulate progressively in myotomal cells along the rostro-caudal axis. This expression is transient and Myf-6 mRNA can no longer be detected in myotomal cells after day 12 post coitum (p.c.). In contrast to other muscle determination genes (MyoD1, myogenin, Myf-5), Myf-6 mRNA is not detected in limb buds or visceral arches and skeletal muscle of the mouse embryo (day 8-15 p.c.). In fetal mice, Myf-6 transcripts appear at day 16 p.c. in all skeletal muscles, and the gene continues to be expressed at a high level after birth. These results suggest that early Myf-6 expression may be restricted to a population of myogenic cells that does not contribute to the embryonic muscle masses in limb buds and visceral arches. The reappearance of Myf-6 mRNA in fetal skeletal muscle coincides approximately with secondary muscle fiber formation and the onset of innervation.

Distinct temporal expression of mouse Nkx-5.1 and Nkx-5.2 homeobox genes during brain and ear development.

The mouse Nkx-5.1 and Nkx-5.2 genes have been identified by sequence homology to Drosophila NK genes within the homeobox domain. Here, we report the isolation of the Nkx-5.2 cDNA and a detailed comparative analysis of the spatio-temporal expression patterns for Nkx-5.1 and Nkx-5.2 genes. Nkx-5.2 transcripts are first detected in E13.5 embryos where they colocalize with Nkx-5.1 mRNA in the developing central nervous system and the inner ear. However, the onset of Nkx-5.1 transcription begins much earlier in 10 somite stage embryos (E8.5) in the otic placode and the branchial region. Nkx-5.1 expression in the ear persists until birth, whereas in branchial arches it is transient between E8.5 to E11.5. Transcript distribution appears regionalized in the otic vesicle concentrating at the anterior and posterior margin and later at the dorsal side of the otocyst. These domains are distinct from regions expressing Pax-2 and sek, two other early markers for otic development. From E11.5 to birth several Nkx-5.1 expression domains appear in the brain between the ventral diencephalon and the myelencephalon. The same expression domains also exist for Nkx-5.2 beginning at E13.5. The regionally restricted expression pattern of both Nkx-5 genes during mouse development suggests their involvement in cell type specification of neuronal cells.

FGFs control the patterning of the inner ear but are not able to induce the full ear program.

FGF2 or FGF8 applied ectopically, close to the developing otic placode enhances transcription of a subset of ear marker genes such as Nkx5-1, SOHo1 and Pax2. Other ear expressed genes (Dlx5 and BMP4) are not up-regulated by FGFs. Ectopic FGFs lead to an increase in size of the vestibulo-cochlear ganglion. This phenotypic change is due to an increased recruitment of epithelial cells to the neuronal fate rather than to an enhanced proliferation. We also observed an induction of additional, vesicle-like structures upon ectopic FGF treatment, but this induction never led to enrolment of a full ear program. We further demonstrate that FGF8 is expressed in two separate, short waves, first at the otic placode stage and later at the vesicle stage. Both activities correspond to critical morphogenetic events in ear development. We propose that FGF8 is an important regulator of otocyst patterning.

Inner ear and lateral line expression of a zebrafish Nkx5-1 gene and its downregulation in the ears of FGF8 mutant, ace.

An orthologue of the mouse homeobox gene Nkx5-1 was cloned and characterized in the zebrafish. As in the mouse and chick, the zebrafish Nkx5-1 gene is expressed in the ear placode and vesicle and in cells forming the vestibulo-acoustic ganglion. In addition, a novel expression domain, the lateral line, appears in the zebrafish, supporting a common precursor hypothesis for these two organs. In the FGF8 zebrafish mutant ace, expression of Nkx5-1 in the otic structures is diminished. The most significant reduction of zfNkx5-1 expression was observed in cells of the vestibulo-acoustic ganglion.

Response to growth hormone with respect to pubertal status on increased dose in idiopathic growth hormone deficiency: an analysis of Turkish children in the KIGS database (Pfizer International Growth Study).

AIM: To compare the growth response to growth hormone (GH) treatment in patients with idiopathic GH deficiency (IGHD) who were prepubertal with the response of those who were pubertal at the onset of GH therapy on an increased GH dose. PATIENTS AND METHODS: Among the Turkish patients enrolled in the Pfizer International Growth Study (KIGS) database with the diagnosis of IGHD, the growth data over 2 years of GH therapy were analyzed longitudinally of 113 (79 M) prepubertal (Group 1) and 44 (33 M) pubertal (Group 2) patients. Pubertal signs were reported to be present initially or to have appeared within 6 months of GH therapy in Group 2. Mean +/- SD age at onset of therapy was 8.7 +/- 3.5 and 13.5 +/- 1.8 years; height SDS -4.2 +/- 1.4 and -3.2 +/- 1.1 (p < 0.05) in Groups 1 and 2, respectively. Mid-parental height (MPH) SDS did not show a significant difference between the two groups (-1.5 +/- 1.1 vs -1.7 +/- 1.1). RESULTS: Delta height SDS over 2 years of therapy was significantly higher in Group 1 (1.1 +/- 1.0) than in Group 2 (0.7 +/- 0.6) (p <0.05) in spite of a significantly lower dose of GH (14.6 +/- 3.3 in Group 1 vs 17.0 +/- 3.1 IU/m2/week in Group 2, p < 0.05). Ht--MPH SDS showed an increase from -2.4 +/- 1.7 to -1.4 +/- 1.5 in Group 1 and from -1.5 +/- 1.5 to -0.8 +/- 1.3 in Group 2. Overall delta height SDS showed negative correlations with age (r = -0.32), height SDS (r = -0.41) and height--MPH SDS (r = -0.40) at onset of therapy (p < 0.001). CONCLUSIONS: These data show that in IGHD the slight increase (15-20%) in the dose of GH during puberty was not adequate to maintain height velocity at the same magnitude as in prepuberty, and thus was not cost effective.

Alkali myosin light chains in man are encoded by a multigene family that includes the adult skeletal muscle, the embryonic or atrial, and nonsarcomeric isoforms.

A set of cDNA clones coding for alkali myosin light chains (AMLC) was isolated from fetal human skeletal muscle. Nucleotide sequence analysis and RNA expression patterns of individual clones revealed related sequences corresponding to (i) fast fiber type MLC1 and MLC3; (ii) the embryonic MLC that is also expressed in fetal ventricle and adult atrium (MLCemb); and (iii) a nonsarcomeric MLC isoform that is found in all nonmuscle cell types and smooth muscle. The AMLC gene family in man comprises unique copies for MLC1, MLC3 and MLCemb, and multiple copies for the nonsarcomeric MLC genes. The gene coding for MLC1 and MLC3 is located on human chromosome 2.

Evidence for a signal peptide at the amino-terminal end of human mitochondrial aldehyde dehydrogenase.

A full-length cDNA clone coding for human mitochondrial aldehyde dehydrogenase (ALDH I) was isolated from a human fetal muscle cDNA library. Sequence analysis revealed structural similarities between the amino-terminal end of ALDH I and other known targeting sequences responsible for protein uptake into the mitochondria.

Development of the vertebrate inner ear.

The inner ear, also called the membranous labyrinth, contains the cochlea, which is responsible for the sense of hearing, and the vestibular apparatus, which is necessary for the sense of balance and gravity. The inner ear arises in the embryo from placodes, which are epithelial thickenings of the cranial ectoderm symmetrically located on either side of hindbrain rhombomeres 5 and 6. Placode formation in mice is first visible at the 12-somite stage and is controlled by surrounding tissues, the paraxial mesoderm and neural ectoderm. Diffusible molecules such as growth factors play an important role in this process. The activity of several genes confers the identity to the placodal cells. Subsequent cellular proliferation processes under influences from the adjacent hindbrain cause the inner ear epithelium to invaginate and form a vesicle called the otocyst. Combinatorial expression of several genes and diffusible factors secreted from the vesicle epithelium and hindbrain control specification of distinct inner ear compartments. Transplantation studies and inner ear in vitro cultures show that each of these compartments is already committed to develop unique inner ear structures. Later developmental periods are principally characterized by intrinsic differentiation processes. In particular, sensory patches differentiate into fully functional sensory epithelia, and the semicircular canals along with the cochlear duct are elaborated and ossified.

Regionalized expression of Nkx5-1, Nkx5-2, Pax2 and sek genes during mouse inner ear development.

Nkx5-1 and Nkx5-2 are two highly related homeobox genes which are expressed during mouse development in the inner ear. Here, we present the detailed expression of both genes within the developing ear and a comparison to the expression of other potential control genes in this organ. Both genes are active between E13.5 and birth in non-sensory epithelium of the semicircular canals, utricle and saccule. Nkx5-1 and Nkx5-2 are also expressed in the cochlea, where the expression is restricted to the stria vascularis. The endolymphatic duct is devoid of any Nkx5 transcripts. Pax2 is expressed in epithelial cells of the ventral part of the membranous labyrinth where it overlaps with the Nkx5 expression domain. sek shows a complementary pattern to Nkx5 in the vestibular epithelium. In the cochlea sek is expressed throughout the mesenchyme and epithelium but not in the stria vascularis. In the vestibulum Pax2 and sek is limited to the ventral part whereas Nkx5 genes are active throughout. These data suggest that Nkx5 genes, Pax2 and sek play different roles in the patterning of inner ear structures.

Isolation of repetitive clones from human muscle cDNA library.

Human fetal muscle cDNA library was screened with a beta-myosin heavy chain gene fragment containing Alu sequences. Two cDNA clones AI and BII with 1.8 and 3 kb inserts respectively were chosen for further characterization by means of RNA and DNA hybridization procedures and sequencing. The clones appeared to contain repetitive sequences as well as single copy regions. They are actively transcribed in different stages of myogenic development but not in the liver. DNA sequence analysis of short stretches from both clones revealed no sequence homology to any other published DNA sequences.

Sotos syndrome with septo-optic dysplasia.

A 12 2/12 year-old boy was admitted to our hospital with the complaint of rapid growth. His birth and postnatal growth history, developmental retardation, physical examination and skeletal radiograms suggested Sotos syndrome. CT and MRI findings revealed septo-optic dysplasia (SOD), which is usually characterized by poor growth, together with cerebral gigantism in our case. These two entities are both rare and as far as we know this is the first patient in the literature with Sotos syndrome and SOD.

Partial remission phase and metabolic control in type 1 diabetes mellitus in children and adolescents.

A better understanding of the remission phase, while residual beta-cell function is still present in recently diagnosed type 1 (insulin dependent) diabetes mellitus (IDDM), is very important because of the potential for pharmacological intervention to preserve this function. To evaluate the natural course and characteristics of the remission phase in children and adolescents with IDDM, a retrospective study was performed on patients diagnosed with IDDM under the age of 18 years during the years 1991-1998. Sixty-two patients whose medical records were available were included in the study. Data were collected by reviewing the hospital records of patients from the time of diagnosis through the first 24 months after diagnosis. The duration of symptoms and history of infection prior to presentation, diabetic ketoacidosis (DKA) at diagnosis, length of hospitalization, initial glucose level, basal C-peptide levels at diagnosis, daily insulin requirements per kg body weight and HbA1c at diagnosis and at each visit were recorded. Thirty-five patients (56.5%) entered partial remission. We observed similar remission rates in those aged <10 and > or =10 years at diagnosis and in boys and girls. History of infection and presentation with DKA were associated with a lower rate of remission (p<0.001, p<0.0001, respectively) and were more commonly observed under the age of 10 years (p<0.0001, p<0.0001, respectively). The average insulin requirements per kg body weight calculated at diagnosis decreased with increasing age (r = -0.31, p = 0.012). The length of time until remission was 1.36+/-1.03 (mean +/- SD) months and positively correlated with insulin requirements at discharge from the hospital (r = 0.63, p<0.0001). Mean duration of remission was 11.67+/-5.82 months and was much longer in boys than girls (p<0.05). Six patients, all boys, entered total remission for 3.80+/-3.73 months. HbA1c concentrations in the first year of the disease were significantly lower in patients who underwent a remission phase (7.31+/-1.24% vs. 8.24+/-1.47%, p <0.05). However, this difference was not observed during the second year of the disease. In conclusion, history of infection prior to presentation and DKA at diagnosis were associated with young age and were the most important factors negatively influencing the remission rate in newly diagnosed IDDM patients.

Vitamin A and beta carotene levels in constitutional delay of growth and puberty.

The objective of this study was to investigate the vitamin A (vit A) status and beta carotene levels of children with constitutional delay of growth and puberty (CDGP). Serum vit A and beta-carotene levels of 26 children with CDGP were measured. 20 age-matched healthy children with normal pubertal development served as controls. Except for the height SDS, which was significantly lower in the CDGP group (p < 0.05), no significant differences were found between chronological ages, weight for height indices and beta-carotene levels of the two groups (p > 0.05). Although serum vit A levels of children in both groups were within normal limits according to WHO criteria, serum vit A levels were significantly lower in the CDGP group than in controls (44.13 +/- 12.25 and 59.60 +/- 19.75 micrograms/dl respectively, p < 0.05). It was concluded that vit A deficiency may play a role in CDGP in developing countries.

Helicobacter pylori infection in children with constitutional delay of growth and puberty.

Helicobacter pylori is a gastroduodenal pathogen strongly associated with chronic gastritis and duodenal ulceration. It is thought that H. pylori infection might be one of the causes of growth retardation in children. The aim of this study was to evaluate the seroprevalence of H. pylori in children with constitutional delay of growth and puberty (CDGP). H. pylori seropositivity was studied in 24 children with CDGP (22 M, 2 F) and 32 healthy age-matched children with normal pubertal development. Mean age of the children with CDGP was 14.53 +/- 1.12 yr and all of them had been diagnosed as CDGP after physical and laboratory assessment. H. pylori IgG positivity was detected in 16 of the 24 children with CDGP (66.6%) and 12 of 32 controls (37.5%) (p <0.05). This finding is consistent with the hypothesis that H. pylori infection could be one of the environmental factors causing CDGP.

Bilateral breast masses and bloody nipple discharge in a two year-old boy.

Breast enlargement with bloody discharge is very rare in childhood. We report a two year-old boy with breast enlargement and bloody discharge. Because of persistent bloody discharge, subcutaneous mastectomy was performed. The specimen showed histologic changes identical to those seen in adult mammary duct ectasia. We suggested that the infant's own endocrine system is responsible for breast enlargement and mammary duct ectasia, possibly occurring as a result of a mechanism similar to that in adults.