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Acute hypokalemic paralysis is a rare cause of acute weakness. Thyrotoxic periodic paralysis (TPP) is an unusual complication of hyperthyroidism. It is characterized by sudden onset of hypokalemia condition resulting from a shift of potassium into cells and paralysis that primarily affects the lower extremities. Failure to recognize TPP may lead to improper management. Treatment of TPP includes replacing potassium rapidly, using nonselective beta-blockers and correcting the underlying hyperthyroidism as soon as possible. TPP is curable once euthyroid state is achieved. We describe a 13-year-old male with Down syndrome who presented with acute onset of lower extremity weakness secondary to acute hypokalemia and was found to have new onset Graves' disease.La hipokalemia aguda es una causa poco frecuente de debilidad muscular. La parálisis periódica tirotóxica es una complicación infrecuente de la tirotoxicosis, en sus diferentes etiologías, en la cual se produce hipokalemia por un flujo masivo de potasio al compartimiento intracelular, que provoca parálisis muscular, que afecta, principalmente, la musculatura proximal de los miembros inferiores. Es importante reconocer esta entidad para instaurar un tratamiento adecuado que incluya el rápido suplemento de potasio y el uso de beta-bloqueantes no selectivos. El tratamiento del hipertiroidismo subyacente y el retorno al estado eutiroideo es imprescindible para la resolución de los episodios de parálisis periódica tirotóxica. Aquí se presenta a un paciente de 13 años de edad con síndrome de Down que consultó por debilidad muscular de los miembros inferiores y trastorno de la marcha, asociada a hipokalemia aguda, en el que se realizó el diagnóstico de hipertiroidismo por enfermedad de Graves.

Androgen insensitivity syndrome (AIS) is a hereditary condition in patients with a 46,XY karyotype in which loss-of-function mutations of the androgen receptor (AR) gene are responsible for defects in virilization. The aim of this study was to investigate the consequences of the lack of AR activity on germ cell survival and the degree of testicular development reached by these patients by analyzing gonadal tissue from patients with AIS prior to Sertoli cell maturation at puberty. Twenty-three gonads from 13 patients with AIS were assessed and compared to 18 testes from 17 subjects without endocrine disorders. The study of the gonadal structure using conventional microscopy and the ultrastructural characteristics of remnant germ cells using electron microscopy, combined with the immunohistochemical analysis of specific germ cell markers (MAGE-A4 for premeiotic germ cells and of OCT3/4 for gonocytes), enabled us to carry out a thorough investigation of germ cell life in an androgen-insensitive microenvironment throughout prepuberty until young adulthood. Here, we show that germ cell degeneration starts very early, with a marked decrease in number after only 2 years of life, and we demonstrate the permanence of gonocytes in AIS testis samples until puberty, describing 2 different populations. Additionally, our results provide further evidence for the importance of AR signaling in peritubular myoid cells during prepuberty to maintain Sertoli and spermatogonial cell health and survival. Fil: Aliberti, Paula. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Perez Garrido, Natalia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Marino, Roxana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Ramirez, Pablo. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Solari, Alberto Juan. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Sciurano, Roberta Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina; Argentina Fil: Costanzo, Mariana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Guercio, Gabriela Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Warman, Diana Mónica. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Bailez, Marcela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Baquedano, María Sonia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Rivarola, Marco Aurelio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Belgorosky, Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Berensztein, Esperanza Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina

Healthcare budgets worldwide are facing increasing pressureto reduce costs and improve efficiency, while maintainingquality. Laboratory testing has not escaped thispressure.The clinical laboratory control of demand is oftenconfused with demand management. Control of demandrefers to the reduction of costs, while demand managementfocusses on ensuring appropriate requesting. Hence,the latter has an inbuilt quality aspect and may result inincreased as well as decreased testing (i.e. to reduce overordering,underordering and misordering of tests) [1, 2].It has been widely accepted that the major changes inthyroid function in adult subjects may initially be studiedby assessing of thyroid-stimulating hormone (TSH) [3].Free thyroxine (fT4) should be measured in the setting ofan abnormal TSH, and free triiodothyronine (fT3) only inspecific circumstances, such as cases of suspected hyperthyroidismwith a normal fT4 and suppressed TSH [4].The recommendations by Wisely et al. [5] from theAmerican Society for Clinical Pathology (ASCP) adviseagainst ordering multiple tests in the initial investigationof patients with suspected non-neoplastic thyroid disease.In the paediatric population the impact of thyroidhormone deficiency on neuro development and growth,warrant evaluation of an aetiology of central origin. Herewe propose the use of serum TSH and fT4 to evaluateprimary and central thyroid dysfunction in this population[6, 7]. However, to our knowledge, currently noevidence exists on whether serum TSH and fT4 providesufficient information for the screening of thyroid functionin children.The aim of the study was to retrospectively assessserum full thyroid profile (TSH, fT4, T4 and T3) vs. TSHand fT4 only for the primary evaluation of thyroid diseasein children describing the results obtained and subsequentmedical management.We retrospectively analysed consecutive patients(n = 5999) in whom thyroid function was studied with afull thyroid test seen between November 2014 and September2015. Tests were performed on the day of sampling. Weexcluded those subjects who were previously diagnosedwith thyroid disease, those that were not seen by anyphysician after the studies, those who had been treatedwith levothyroxine (LT), methimazole, or antiepilepticdrugs, and severely ill patients. The remaining 5738 subjectsincluded were categorised into 12 groups accordingto age from 1 week to 12 years. TSH, T3 and fT4 weremeasured with Architect i4000 (Abbott) and we used ourown reference interval (RI) [8] for total T4 IMMULITE 2000(Siemens) and was used the RI by Elmlinger et al. [9]. Allwith percentiles between 2.5 and 97.5.Subjects with serum TSH and fT4 within the (RI)according to age were selected (n = 4007, 69.8%).From this group, children who had T3 and/or T4outside the RI were selected (n = 390, 6.79%) (Figure 1)(Supplementary Material 1 and 2). In the clinical records (CR) of 381 patients (6.63%) nocomment was made on thyroid function or the thyroidprofile was reported to be normal, in spite of T3 and/or T4outside the RI.In nine patients (0.15%) a comment was made inthe CR; five patients were sent home without further interventions, in one patient with high T3 and T4, highserum levels of thyroxine-binding globulin were found,and the three remaining were finally treated with LT(0.05% from de selected subjects). All of them had fT4below the 10th percentile of the RI and one additionallyhad TSH above the 90th percentile of the RI.Of the study population n = 5738, 69.8% presentedwith normal serum TSH and fT4 levels. Overall patients,6.79% had T3 and/or T4 outside the RI, which is statisticallyacceptable for a reference population. Accordingto the definition of RI using the central 95% values fromreference population in both analytes, 5% of healthy subjectsis statistically expected to be found outside the RI, ifwe used two analytes is possible to found almost 9.75% ofhealthy subjects outside the RI ([1?(0.95)2] *100 = 9.75%).In the CR of 381 patients (6.63%) no comment wasmade, this may have happened because in all cases T3and/or T4 were within the reference change value (RCV)on the limits of the RI (Supplementary Material 2).As to the nine patients that had some medicalcomment in their CR regarding thyroid test results, onlythree were put on treatment, and all had fT4 below the10th percentile and one had TSH above the 90th percentileas well. Moreover, the three patients who duringfollow-up showed a drop in serum thyroid hormones,and showed clinical signs of hypothyroidism and werestarted on supplementary treatment with LT had medulloblastoma,neurofibromatosis and Prader-Willi syndrome,diseases that may be associated with centralhypothyroidism. In adults the use of only serum TSH by primary careproviders, may be sufficient for screening of thyroiddisease. However, in children functional disorders of thethyroid, such as hypothyroidism and hyperthyroidism dueto chronic lymphocytic thyroiditis and Graves? Basedowdisease, are frequent. The combination of TSH and fT4allows detection of these two disorders as well as the centralabnormalities of the hypothalamus pituitary thyroid axis;the findings in our series support this concept.When considering cost-effectiveness, costs could bereduced by 46% in each patient studied, with a positiveimpact on the management of demand without effectingclinical outcome.In conclusion, we found that the use of TSH and fT4is useful for primary evaluation of thyroid disease in paediatrics.However, TSH and fT4 should be assessed with astricter RI between the 10th and 90th percentile. In caseof persistent clinical signs suggestive of a disorder of thethyroid gland in a child, assessment of a complete thyroidprofile, including antithyroid antibodies, total or free T3,and total T4, is recommended.This study suggests that questionable testing patternscontribute to inappropriate thyroid test utilisation. A prospectivestudy in a paediatric population would be necessaryto clinically confirm these results and subsequentlydefine medical management. Fil: Zaidman, Verónica. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Lazzati, Juan Manuel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Maceiras, Mercedes Carmen. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Herzovich, Viviana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Pelanda, Melina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Ribas, Alejandra. Fundacion Hospital de Pediatria Professor Dr. Juan P. Garrahan; Argentina Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Chaler, Eduardo Adrian. Fundacion Hospital de Pediatria Professor Dr. Juan P. Garrahan; Argentina

STUDY QUESTION What is the genetic landscape within the testis of the juvenile rhesus monkey (Macaca mulatta) that underlies the decision of undifferentiated spermatogonia to commit to a pathway of differentiation when puberty is induced prematurely by exogenous LH and FSH stimulation? SUMMARY ANSWER Forty-eight hours of gonadotrophin stimulation of the juvenile monkey testis resulted in the appearance of differentiating B spermatogonia and the emergence of 1362 up-regulated and 225 down-regulated testicular mRNAs encoding a complex network of proteins ranging from enzymes regulating Leydig cell steroidogenesis to membrane receptors, and from juxtacrine and paracrine factors to transcriptional factors governing spermatogonial stem cell fate. WHAT IS KNOWN ALREADY Our understanding of the cell and molecular biology underlying the fate of undifferentiated spermatogonia is based largely on studies of rodents, particularly of mice, but in the case of primates very little is known. The present study represents the first attempt to comprehensively address this question in a highly evolved primate. STUDY DESIGN, SIZE, DURATION Global gene expression in the testis from juvenile rhesus monkeys that had been stimulated with recombinant monkey LH and FSH for 48 h (N = 3) or 96 h (N = 4) was compared to that from vehicle treated animals (N = 3). Testicular cell types and testosterone secretion were also monitored. PARTICIPANTS/MATERIALS, SETTING, METHODS Precocious testicular puberty was initiated in juvenile rhesus monkeys, 14-24 months of age, using a physiologic mode of intermittent stimulation with i.v. recombinant monkey LH and FSH that within 48 h produced â adult' levels of circulating LH, FSH and testosterone. Mitotic activity was monitored by immunohistochemical assays of 5-bromo-2′-deoxyuridine and 5-ethynyl-2′-deoxyuridine incorporation. Animals were bilaterally castrated and RNA was extracted from the right testis. Global gene expression was determined using RNA-Seq. Differentially expressed genes (DEGs) were identified and evaluated by pathway analysis. mRNAs of particular interest were also quantitated using quantitative RT-PCR. Fractions of the left testis were used for histochemistry or immunoflouresence. MAIN RESULTS AND THE ROLE OF CHANCE Differentiating type B spematogonia were observed after both 48 and 96 h of gonadotrophin stimulation. Pathway analysis identified five super categories of over-represented DEGs. Repression of GFRA1 (glial cell line-derived neurotrophic factor family receptor alpha 1) and NANOS2 (nanos C2HC-type zinc finger 2) that favor spermatogonial stem cell renewal was noted after 48 and 96 h of LH and FSH stimulation. Additionally, changes in expression of numerous genes involved in regulating the Notch pathway, cell adhesion, structural plasticity and modulating the immune system were observed. Induction of genes associated with the differentiation of spermatogonia stem cells (SOHLH1(spermatogenesis- A nd oogenesis-specific basic helix-loop-helix 1), SOHLH2 and KIT (V-Kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog)) was not observed. Expression of the gene encoding STRA8 (stimulated by retinoic acid 8), a protein generally considered to mark activation of retinoic acid signaling, was below our limit of detection. LARGE SCALE DATA The entire mRNA data set for vehicle and gonadotrophin treated animals (N = 10) has been deposited in the GEO-NCBI repository (GSE97786). LIMITATIONS REASONS FOR CAUTION The limited number of monkeys per group and the dilution of low abundance germ cell transcripts by mRNAs contributed from somatic cells likely resulted in an underestimation of the number of differentially expressed germ cell genes. WIDER IMPLICATIONS OF THE FINDINGS The findings that expression of GDNF (a major promoter of spermatogonial stem cell renewal) was not detected in the control juvenile testes, expression of SOHLH1, SOHLH2 and KIT, promoters of spermatogonial differentiation in mice, were not up-regulated in association with the gonadotrophin-induced generation of differentiating spermatogonia, and that robust activation of the retinoic acid signaling pathway was not observed, could not have been predicted. These unexpected results underline the importance of non-human primate models in translating data derived from animal research to the human situation. Fil: Ramaswamy, Suresh. University of Pittsburgh at Johnstown; Estados Unidos. University of Pittsburgh; Estados Unidos Fil: Walker, William H.. University of Pittsburgh; Estados Unidos. University of Pittsburgh at Johnstown; Estados Unidos Fil: Aliberti, Paula. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Sethi, Rahil. University of Pittsburgh; Estados Unidos. University of Pittsburgh at Johnstown; Estados Unidos Fil: Marshall, Gary R.. Chatham University; Fil: Smith, Alyxzandria. University of Pittsburgh; Estados Unidos. University of Pittsburgh at Johnstown; Estados Unidos Fil: Nourashrafeddin, Seyedmehdi. University of Pittsburgh at Johnstown; Estados Unidos. University of Pittsburgh; Estados Unidos Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Chandran, Uma R.. University of Pittsburgh; Estados Unidos. University of Pittsburgh at Johnstown; Estados Unidos Fil: Hedger, Mark P.. Hudson Institute Of Medical Research; Australia Fil: Plant, Tony M.. University of Pittsburgh; Estados Unidos. University of Pittsburgh at Johnstown; Estados Unidos

Giant prolactinomas are rare pituitary adenomas characterized by their great local invasion. In this paper, we report a 15-year-old male with left retro-ocular pain and ipsilateral exophthalmos of 4 months of evolution, secondary to a tumour in the base of the skull that invaded the orbit. Hormonal studies revealed serum prolactin of 6913,7 ng/ml (normal value20), confirming the diagnosis of giant prolactinoma. The patient started treatment with the dopaminergic agonist cabergoline in increasing doses. After 7 months of follow-up the prolactin had decreased to 349.8 ng/ml and the tumor volume was reduced by 70%, without presenting adverse effects to the treatment. The patient was asymptomatic and had restarted puberty. The rapid remission of symptoms without the need for invasive treatments underlines the importance of considering the diagnosis of prolactinoma among the possible differential diagnoses of tumor of the skull base.El prolactinoma gigante es un adenoma pituitario poco frecuente caracterizado por su gran invasión local. Se reporta el caso de un varón de 15 años de edad con dolor retroocular izquierdo y exoftalmos ipsilateral de 4 meses de evolución secundario a un tumor en la base del cráneo que invadía la órbita. Los estudios hormonales revelaron prolactina sérica de 6913,7 ng/ml (valor normal20), que confirmó el diagnóstico de prolactinoma gigante. El paciente inició un tratamiento con el agonista dopaminérgico cabergolina en dosis crecientes. Luego de 7 meses de seguimiento, la prolactina había descendido a 349,8 ng/ml y el volumen del tumor se redujo un 70%, sin efectos adversos al tratamiento. El paciente se encontraba asintomático y había reiniciado la pubertad. La rápida remisión de los síntomas sin necesidad de tratamientos invasores subraya la importancia de considerar el diagnóstico de prolactinoma entre los posibles diagnósticos diferenciales de tumor de la base del cráneo.

Congenital adrenal hyperplasia (CAH), resulting from mutations in CYP11B1, a gene encoding 11β-hydroxylase, represents a rare autosomal recessive Mendelian disorder of aberrant sex steroid production. Unlike CAH caused by 21-hydroxylase deficiency, the disease is far more common in the Middle East and North Africa, where consanguinity is common often resulting in identical mutations. Clinically, affected female newborns are profoundly virilized (Prader score of 4/5), and both genders display significantly advanced bone ages and are oftentimes hypertensive. We find that 11-deoxycortisol, not frequently measured, is the most robust biochemical marker for diagnosing 11β-hydroxylase deficiency. Finally, computational modeling of 25 missense mutations of CYP11B1 revealed that specific modifications in the heme-binding (R374W and R448C) or substrate-binding (W116C) site of 11β-hydroxylase, or alterations in its stability (L299P and G267S), may predict severe disease. Thus, we report clinical, genetic, hormonal, and structural effects of CYP11B1 gene mutations in the largest international cohort of 108 patients with steroid 11β-hydroxylase deficiency CAH. Fil: Khattab, Ahmed. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Haider, Shozeb. University College London; Estados Unidos Fil: Kumar, Ameet. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Dhawan, Samarth. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Alam, Dauood. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Romero, Raquel. University College London; Estados Unidos Fil: Burns, James. University College London; Estados Unidos Fil: Li, Di. University College London; Estados Unidos Fil: Estatico, Jessica. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Rahi, Simran. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Fatima, Saleel. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Alzahrani, Ali. King Faisal Specialist Hospital And Research Centre; Arabia Saudita Fil: Hafez, Mona. Cairo University; Egipto Fil: Musa, Noha. Cairo University; Egipto Fil: Azar, Maryam Razzghy. Iran University Of Medical Sciences; Irán Fil: Khaloul, Najoua. Hopital Farhat Hached Sousse; Túnez Fil: Gribaa, Moez. Hopital Farhat Hached Sousse; Túnez Fil: Saad, Ali. Hopital Farhat Hached Sousse; Túnez Fil: Charfeddine, Ilhem Ben. Hopital Farhat Hached Sousse; Túnez Fil: De Mendonça, Berenice Bilharinho. Universidade de Sao Paulo; Brasil Fil: Belgorosky, Alicia. Hospital de Pediatria Samic Prof. Dr. Juan P. Garrahan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Dumic, Katja. University Of Zagreb. School Of Medicine; Croacia Fil: Dumic, Miroslav. University Of Zagreb. School Of Medicine; Croacia Fil: Aisenberg, Javier. Hackensack University Medical Center; Estados Unidos Fil: Kandemir, Nurgun. Hacettepe Universitesi; Turquía Fil: Alikasifoglu, Ayfer. Hacettepe Universitesi; Turquía Fil: Ozon, Alev. Hacettepe Universitesi; Turquía Fil: Gonc, Nazli. Hacettepe Universitesi; Turquía Fil: Cheng, Tina. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Kuhnle Krahl, Ursula. University of Munich; Alemania Fil: Cappa, Marco. Ospedale Pediatrico Bambino Gesu; Italia Fil: Holterhus, Paul-Martin. Universitatsklinikum Schleswig-Holstein; Alemania Fil: Nour, Munier A.. University of Saskatchewan; Canadá Fil: Pacaud, Daniele. University of Calgary; Canadá Fil: Holtzman, Assaf. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Li, Sun. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Zaidi, Mone. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: Yuen, Tony. Icahn School Of Medicine At Mount Sinai; Estados Unidos Fil: New, Maria I.. Icahn School Of Medicine At Mount Sinai; Estados Unidos

Steroid acute regulatory (StAR) protein is a mitochondria-targeted protein that is part of the transduceosome complex crucial for transport of cholesterol to mitochondria. Recessive mutations cause classic and nonclassic congenital lipoid adrenal hyperplasia.The aim of this study was to report the clinical, hormonal, genetic, and functional data of a novel heterozygous mutation in the StAR gene found in a 46,XY patient with ambiguous genitalia and neonatal severe steroidogenic deficiency.Undetectable serum steroids with high ACTH and plasma renin activity but normal acute GnRH response were found in infancy. After gonadectomy (at 3 yr of age), serum LH and testosterone were undetectable, whereas FSH was normal but increased slowly afterward. Estrogen replacement therapy, started at 10.2 yr of age, suppressed gonadotropins (for 2 yr). However, after 1 month off estrogens, the patient showed castrated levels. At 11.9 yr old, after fludrocortisone withdrawal because of hypertension, plasma renin activity and aldosterone remained normal, suggesting mineralocorticoid recovery by a StAR-independent mechanism.We found a de novo heterozygous IVS-2AG StAR mutation and the reported heterozygous p.G146A SF1 polymorphism with normal CYP11A1, FDXR, FDX1, VDAC1, and TSPO genes. The mutant StAR transcript lacked exon 2, resulting in the in-frame loss of amino acids 22 to 59 in the N-terminal mitochondrial targeting signal. In vitro, the mutant protein exhibited reduced StAR activity in a dominant-negative manner and almost no mitochondria localization.A misfolded p.G22_L59del StAR might interfere with wild-type StAR activity by blocking the transduceosome complex, causing an autosomal dominant form of StAR deficiency, explaining the clinical phenotype. We speculated that estrogen might have modulated mineralocorticoid function and pubertal maturation in a human natural model lacking endogenous steroid production.

Several heterozygous GLI2 gene mutations have been reported in patients with isolated GH deficiency (IGHD) or multiple pituitary hormone deficiency (MPHD) with or without other malformations. The primary aim of this study was to analyze the presence of GLI2 gene alterations in a cohort of patients with IGHD or MPHD and ectopic/absent posterior pituitary. The coding sequence and flanking intronic regions of GLI2 gene were amplified and directly sequenced from gDNA of 18 affected subjects and relatives. In silico tools were applied to identify the functional impact of newly found variants (Polyphen2, SIFT, Mutation Taster). We identified two novel heterozygous missense variations in two unrelated patients, p.Arg231Gln and p.Arg226Leu, located in the repressor domain of the protein. Both variations affect highly conserved amino acids of the Gli2 protein and were not found in the available databases. In silico tools suggest that these variations might be disease causing. Our study suggests that the GLI2 gene may be one of the candidate genes to analyze when an association of pituitary hormone deficiency and developmental defects in posterior pituitary gland. The highly variable phenotype found suggests the presence of additional unknown factors that could contribute to the phenotype observed in these patients.

Background Children born small for gestational age (SGA) experience higher rates of morbidity and mortality than those born appropriate for gestational age. In Latin America, identification and optimal management of children born SGA is a critical issue. Leading experts in pediatric endocrinology throughout Latin America established working groups in order to discuss key challenges regarding the evaluation and management of children born SGA and ultimately develop a consensus statement. Discussion SGA is defined as a birth weight and/or birth length greater than 2 standard deviations (SD) below the population reference mean for gestational age. SGA refers to body size and implies length-weight reference data in a geographical population whose ethnicity is known and specific to this group. Ideally, each country/region within Latin America should establish its own standards and make relevant updates. SGA children should be evaluated with standardized measures by trained personnel every 3 months during year 1 and every 6 months during year 2. Those without catch-up growth within the first 6 months of life need further evaluation, as do children whose weight is ≤ -2 SD at age 2 years. Growth hormone treatment can begin in SGA children > 2 years with short stature (< -2.0 SD) and a growth velocity < 25th percentile for their age, and should continue until final height (a growth velocity below 2 cm/year or a bone age of > 14 years for girls and > 16 years for boys) is reached. Blood glucose, thyroid function, HbA1c, and insulin-like growth factor-1 (IGF-1) should be monitored once a year. Monitoring insulin changes from baseline and surrogates of insulin sensitivity is essential. Reduced fetal growth followed by excessive postnatal catch-up in height, and particularly in weight, should be closely monitored. In both sexes, gonadal function should be monitored especially during puberty. Summary Children born SGA should be carefully followed by a multidisciplinary group that includes perinatologists, pediatricians, nutritionists, and pediatric endocrinologists since 10% to 15% will continue to have weight and height deficiency through development and may benefit from growth hormone treatment. Standards/guidelines should be developed on a country/region basis throughout Latin America.

Growth retardation is a considerable clinical problem in children with chronic kidney disease (CKD). Optimization of metabolic and nutritional parameters does not always lead to improved growth. Recombinant human growth hormone (rhGH) treatment has been used to improve height. Several studies in the literature have shown increased growth velocity, although data on the final height (FH) reached are scarce. We assessed the effect of rhGH on FH standard deviation score (SDS) in children with CKD following renal transplantation (RTx), comparing it with patients who did not receive rhGH (control group) but were treated with the same protocol and followed up in a single Center. Thirty-three patients received rhGH treatment until FH. Fourteen who refused rhGH therapy were included in the controls. Prognostic factors for FH and changes in glomerular filtration rate (GFR) during follow-up were also analyzed FH SDS in rhGH-treated patients was significantly higher than in controls (−1.88 ± 1.14 vs −3.48 ± 1.19 SDS, respectively, p

In humans, steroidogenic factor 1 (NR5A1/SF-1) mutations have been reported to cause gonadal dysgenesis, with or without adrenal failure, in both 46,XY and 46,XX individuals. We have previously reported extreme within-family variability in affected 46,XY patients. Even though low ovarian reserve with preserved fertility has been reported in females harboring NR5A1 gene mutations, fertility has only been observed in one reported case in affected 46,XY individuals. A kindred with multiple affected members presenting gonadal dysgenesis was studied. Four 46,XY individuals presented severe hypospadias at birth, one of them associated with micropenis and cryptorchidism. The other 3 developed spontaneous male puberty, and 1 has fathered 5 children. Four 46,XX patients presented premature ovarian failure (one of them was not available for the study) or high follicle-stimulating hormone levels. Mutational analysis of the NR5A1 gene revealed a novel heterozygous mutation, c.938G→A, predicted to cause a p.Arg313Hys amino acid change. A highly conserved amino acid of the ligand-binding domain of the mature protein is affected, predicting abnormal protein function. We confirm that preserved fertility can be observed in patients with a 46,XY disorder of sex development due to heterozygous mutations in the NR5A1 gene.

Background: Three novel heterozygous SF-1 gene mutations affecting multiple members of two unrelated families with a history of 46,XY disorders of sex development (DSD) and 46,XX ovarian insufficiency are described. Methods: Clinical and mutational analysis of the SF-1 gene in 9 subjects of two families. Results: Family 1 had 2 affected 46,XY DSD subjects. One, born with severe perineal hypospadias, was raised as a male, and presented normal adolescence. The other, born with ambiguous genitalia, uterus, and mild testicular dysgenesis, was raised as a female. A W279X heterozygous mutation and an intronic deletion (g3314-3317delTCTC (IVS 4 + 8) was found in the SF-1 gene. In family 2, 4/6 affected siblings had 46,XY DSD or hypospadias. An affected 46,XX sister had normal sexual development but increased FSH levels. The 37-year-old affected mother had entered menopause. An Y183X heterozygous mutation was detected. Conclusion: An extreme within-family phenotypic variability, ranging from severe prenatal undervirilization to normal pubertal development, was observed in 46,XY-affected siblings, indicating that other unknown factors might be involved in the phenotype. Low ovarian reserve and preserved fertility in 46,XX subjects can be observed in heterozygous SF-1 gene mutations.

Patients with TSH-beta subunit defects and congenital hypothyroidism are missed by TSH-based neonatal screening.Our objective was to report the molecular consequences of a novel splice-junction mutation and a novel missense mutation in the TSH-beta subunit gene found in two patients with congenital central hypothyroidism and conventional treatment-resistant anemia.Patient 1 had a homozygous G to A nucleotide change at the 5' donor splice site of exon/intron 2. This resulted in a silent change at codon 34 of the mature protein. In vitro splicing assays showed that the mutant minigene dramatically affected pre-mRNA processing, causing exon 2 to be completely skipped. The putative product from a new out-of-frame translational start point in exon 3 is expected to yield a nonsense 25-amino-acid peptide. In patient 2, sequence analysis revealed a compound heterozygosis for the already reported 313delT (C105Vfs114X) mutation and for a second novel mutation in exon 3, substituting G for A at cDNA nucleotide position 323, resulting in a C88Y change. This cysteine residue is conserved among all dimeric pituitary and placental glycoprotein hormone-beta subunits. Data from in silico analysis confirmed that the C88Y mutation would affect subunit conformation. Indeed, two different bioinformatics approaches, PolyPhen and SIFT analysis, predicted C88Y to be a damaging substitution.In isolated TSH deficiency, the exact molecular diagnosis is mandatory for diagnosis of isolated pituitary deficiency, delineation of prognosis, and genetic counseling. Moreover, diagnosis of central hypothyroidism should be considered in the face of severe infant anemia of uncertain etiology.

Disorders of androgen production can occur in all steps of testosterone biosynthesis and secretion carried out by the foetal Leydig cells as well as in the conversion of testosterone into dihydrotestosterone (DHT). The differentiation of Leydig cells from mesenchymal cells is the first walk for testosterone production. In 46,XY disorders of sex development (DSDs) due to Leydig cell hypoplasia, there is a failure in intrauterine and postnatal virilisation due to the paucity of interstitial Leydig cells to secrete testosterone. Enzymatic defects which impair the normal synthesis of testosterone from cholesterol and the conversion of testosterone to its active metabolite DHT are other causes of DSD due to impaired androgen production. Mutations in the genes that codify the enzymes acting in the steps from cholesterol to DHT have been identified in affected patients. Patients with 46,XY DSD secondary to defects in androgen production show a variable phenotype, strongly depending of the specific mutated gene. Often, these conditions are detected at birth due to the ambiguity of external genitalia but, in several patients, the extremely undervirilised genitalia postpone the diagnosis until late childhood or even adulthood. These patients should receive long-term care provided by multidisciplinary teams with experience in this clinical management. Fil: Mendonca, Berenice B.. Universidade de Sao Paulo; Brasil Fil: Costa, Elaine M.F.. Universidade de Sao Paulo; Brasil Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rivarola, Marco Aurelio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Domenice, Sorahia. Universidade de Sao Paulo; Brasil

Background: Insulin resistance (IR), abnormal lipid profile, and other features of the metabolic syndrome have been described in CYP19 gene knockout mice and in aromatase-deficient adult men but not in prepubertal affected girls. Aims: To study insulin sensitivity, as well as the effects of estrogen, metformin and GnRHa treatment on glucose homeostasis, in an aromatase-deficient girl. Methods: Clinical, metabolic and hormonal follow-up data, from 8 to 12 years of age, is presented. Results: At 9 years of age, IR (HOMA 5.6) and glucose intolerance was detected, along with high serum testosterone (2.28 nmol/l), androstenedione (4.92 nmol/l) and FSH (13.4 mIU/ml) levels. Estrogen replacement was ineffective to suppress gonadotropin and androgen levels, as well as IR. Under metformin therapy, she developed type 2 diabetes and acanthosis nigricans. GnRHa administration for 1 year resulted in marked decreases in gonadotropin and serum androgens, but severe IR persisted. Conclusion: Postnatal estrogen replacement and a marked decrease of endogenous androgens failed to improve IR and glucose tolerance. We propose that, in females, the increment of androgens and/or lack of estrogens during fetal life might alter the mechanism of fetal programming of insulin sensitivity.

Adrenarche is a process of postnatal sexual maturation occurring in higher primates, in which there is an increase in the secretion of adrenal androgens. It is the consequence of a process of postnatal organogenesis characterized by the development of a new zone in the adrenal cortex, the zona reticularis (ZR). The mechanism of this phenomenon remains poorly understood, suggesting that it might be a multifactorial event. A relationship between circulating IGF-I, insulin sensitivity, and adrenal androgens has been postulated. Boys and girls have different patterns of changes in insulin sensitivity at puberty, perhaps secondary to differences in the estrogen milieu. Estrogen effects may also play a role in premature adrenarche. Peripheral or local IGF-1 actions could regulate adrenal progenitor cell proliferation and migration. Since adrenal progenitor cells as well as IGF-I and the IGF-R1 are located in the outer zone of the adrenal cortex during childhood and adolescence, this peripheral cell layer, below the capsule, may contain undifferentiated progenitor cells. Therefore, the IGF-R1 signaling pathway might positively modulate the proliferation and migration of adrenal progenitor cell to stimulate the development of adrenal zones, including ZR. However, no evidence of a direct action of IGF-I on ZR was found. In addition, a role for estrogens in the ontogenesis of ZR is suggested by the presence of aromatase (CYP19) in the subcapsular zona glomerulosa and in the adrenal medulla. Estrogens produced locally could act on ZR by interacting with estrogen receptor beta (ERbeta), but not alpha, and membrane estrogen receptor GPR-30. An estradiol-induced increase in DHEA/cortisol ratio was indeed seen in cultures of adrenocortical cells from post-adrenarche adrenals. In summary, several lines of evidence point to the action of multiple factors, such as local adrenal maturational changes and peripheral metabolic signals, on postnatal human adrenal gland ZR formation.

Immunoexpression of IGF-I, IGF-II, type 1 IGF receptor (IGFR), insulin receptor (IR), and GH receptor (GHR) was analyzed in human testis, in three age groups (Gr): Gr1 (neonates), Gr2 (postnatal testicular activation), and Gr3 (early prepuberty). In interstitial cells, low IGF-I and GHR, but moderate IR immunoexpression was observed in all Grs. However, high expression of IGF-II in Gr1, and moderate expression of IGFR in Gr1 and Gr2 were found. In Leydig cell (LC), high expression of IGF-II, moderate expression of IGFR and GHR, and undetectable IGF-I was found. Moreover, IR was highly expressed in Gr2. The effect of IGF-I on cell proliferation (PI) and apoptosis (AI), induction of cytochrome P450 side chain cleavage (cP450scc) immunoexpression, 3beta-hydroxysteroid dehydrogenase mRNA and testosterone (T) secretion was evaluated in human testis cell cultures. IGF-I increased P450scc immunoexpression, 3beta-hydroxysteroid dehydrogenase mRNA, T secretion, and PI, but decreased AI. We propose that IGF-II, mainly through IR, is involved in functional LC differentiation. In some interstitial cells, probably in LC precursors, IGF-II/IR could be involved, among other factors, in the stimulation of PI and/or inhibition of AI, and in LC differentiation.

The responsibility of clinical laboratories includes adequate assay methods, measurement procedures, and the definition of the appropriate quality specifications for each mensurand as well as the identification of criteria required for obtaining the optimal interpretation and utilization of results, with reference intervals and adequate decision limits. Fil: Lazzati, Juan Manuel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Zaidman, Verónica. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Maceiras, Mercedes. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Chaler, Eduardo. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina

La enzima P450 aromatasa (P450Aro) participa en la síntesis de estrógenos a partir de andrógenos. La mutación c655G>A, descripta en forma heterocigota en una niña y en forma homocigota en un hombre adulto, ambos con déficit de aromatasa, genera la disrupción del sitio dador de splicing exón5-intrón5. Se ha postulado que la retención del intrón5 y la generación de una proteína truncada inactiva serían las consecuencias de esta mutación. Sorpresivamente, la paciente presentó desarrollo espontáneo de mamas y niveles puberales de estradiol, sugiriendo una actividad aromatasa (AA) residual. En principio postulamos que la mutación c655G>A generaría la pérdida del exón5 con conservación del marco de lectura, generándose una proteína con menor actividad que podría explicar el déficit parcial. La expresión del ARNm sin exón5 (ARNm- E5) en linfocitos de la paciente sugiere una asociación entre la pérdida del exón y la presencia de la mutación; posteriormente confirmada realizando ensayos de splicing en células Y1. Sin embargo, la expresión del cDNAE5 en células Y1 presentó una AA nula que no explicaría un déficit parcial. La expresión del ARNm-E5 fue detectada en placenta, testículo y adrenal humanos como una variante de splicing normal. Estos resultados indicarían la ocurrencia de splicing alternativo (SA) en la zona codificante de P450Aro como un posible mecanismo regulador de la producción de estrógenos en tejidos esteroidogénicos humanos. La mutación c655G>A podría alterar los mecanismos fisiológicos reguladores del SA del exón5 favoreciendo su exclusión. De esta forma, bajos niveles de ARNm+E5 podrían expresarse aun en presencia de la mutación explicando el fenotipo de déficit parcial observado en la paciente.P450 aromatase (P450Aro), involved in androgen to estrogen conversion, is encoded by the CYP19 gene. P450Aro c655G>A mutation described in heterozygous form in a girl and in homozygous form in an adult male with P450Aro deficiency results in an aberrant splicing due to disruption of a donor splice site. A truncated inactive protein would be expected if intron5 is retained. Surprisingly, the girl described with this mutation showed spontaneous breast development and pubertal estradiol (E2) levels suggesting residual P450Aro activity (AA). Formerly, we postulate the in frame E5 skipping as a consequence of this mutation generating a protein with some degree of activity. When P450Aro mRNA expression was analysed from patient's lymphocytes, an aberrant spliced mRNA lacking E5 (-E5mRNA) was detected, suggesting an association between E5 skipping and the presence of the mutation. Splicing assays in Y1 cells confirmed this association. -Ex5 cDNA expression in Y1 cells resulted in an inactive protein that could not explain patient's phenotype. Exon 5 might be predicted as a poorly defined exon suggesting a susceptibility to splicing mutations and physiological alternative splicing (AS) events. Therefore, -Ex5mRNA was assessed as a natural occurring alternative transcript in normal human steroidogenic tissues. As P450Aro -E5mRNA expression was detected in human term placenta, prepubertal testis and prepubertal adrenal, we might speculate that AS of P450Aro coding region would occur in humans and would be involved in the complex AA regulation. Furthermore, tissue specific regulation of AS might suggest low expression of +E5mRNA from the c655G>A allele explaining residual AA evidenced in the affected girl.

Context: The mechanisms of postnatal adrenal zonation remain unclear.Objective: To provide a clue for a possible role of estrogens in adrenarche, we studied the expression of estrogen receptor (ER)α, ERβ, G protein-coupled receptor (GPR)30, and cP450aromatase (cP450arom) in human adrenal tissue.Design: Human adrenal tissue was collected from three postnatal age groups (Grs): Gr 1, younger than 3 months (n = 12), fetal zone involution; Gr 2, 3 months to 6 yr (n = 17), pre-adrenarche; and Gr 3, older than 6–20 yr (n = 12), post-adrenarche period.Results: ERβ mRNA in Grs 1 and 3 was higher than in Gr 2 (P < 0.05). By immunohistochemistry and laser capture microdissection followed by RT-PCR, ERβ was expressed in zona reticularis and fetal zone, GPR30 in zona glomerulosa (ZG) and adrenal medulla, while ERα mRNA and protein were undetectable. cP450arom mRNA in Gr 3 was higher than in Grs 1 and 2 (P < 0.05), and localized to ZG and adrenal medulla by laser capture microdissection. cP450arom Immunoreactivity was observed in adrenal medulla in the three Grs and in subcapsular ZG of Gr 3. Double-immunofluorescence studies revealed that cP450arom and chromogranin A only colocalize in adrenal medulla of subjects younger than 18 months. In these samples, exon 1.b-derived transcript was 3.5-fold higher, while exon 1.a-, 1.c-, and 1.d-derived transcripts were 3.3-, 1.9-, and 1.7-fold lower, respectively, than in subjects older than 6 yr.Conclusions: Our results suggest that estrogens produced locally in adrenal medulla would play a role in zona reticularis functional differentiation through ERβ. The cP450arom and GPR30 expression in subcapsular ZG, colocalizing with a high-cell proliferation index, previously reported, suggests a local GPR30-dependent estrogen action in proliferation and migration of progenitor adrenal cells.

Background/Aims: It was postulated that a high growth hormone (GH) bioactivity might explain the rapid growth rate of neonates. The aim of this study is to verify changes in serum GH biological potency (Bio-/Immuno-GH ratio) and their effects on serum growth factors during the first month of life in term and preterm babies. Methods: Blood samples were collected from 10 small-for-gestational-age preterm (SGAPT), 17 appropriate for gestational age preterm (AGAPT) and 26 AGA term (T) neonates on days 4, 15 and 30 of life to evaluate serum GH values measured by IFMA (IFMA-GH) and bioassay (Bio-GH), serum insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 (IGFBP-3). Results: High serum Bio-GH values on the first few days of life correspond to high IFMA-GH values, suggesting full biological potency of circulating GH. Furthermore, IGF-I/IGFBP-3 molar ratio values in preterm babies were higher than in full-term infants. Conclusions: These data confirmed the hypothesis that the higher growth velocity in the first month of life of preterm neonates is due to an increased bioavailability of IGF-I. A progressive maturation of the hypothalamic-pituitary-IGF-I axis without any alteration in the GH biological potency seems to underpin the increase of the growth factors early in life.

Purpose: Since SF1 gene mutations located in the ligand binding domain are associated with a wide phenotypic spectrum in 46,XY subjects, the functional and structural characterization of these variations is of great interest. The aim of this study is to evaluate the clinical phenotype, hormonal pattern and molecular studies (genetic, functional data and protein structural analysis) in two non-related 46,XY disorder of sex development (DSD) index patients. Methods: Clinical characteristics, genomic DNA sequencing analysis, protein prediction software study and protein structure analysis, and functional characterization of the mutations was carried out. Results: Both index DSD patients showed a similar phenotype, however several affected members of Family 1 showed variable phenotypes. While in Family 1 a previously reported heterozygous missense point mutation (p.Arg313His) was found, in Family 2 a novel heterozygous missense point mutation (p.Ser303Arg) was detected. Both mutations were predicted to be as “probably damaging”. The transcriptional activity of SF1 mutants p.Arg313His and p.Ser303Arg, studied using two different promoters in two cell lines, exhibited significant reductions of transactivation activity. Structural analysis showed differences between both mutants, such as changes in the flexibility of the receptor backbone and in the tertiary structure around the ligand and in the AF-2 domain. Conclusions: One of these ligand binding domain mutations in SF1 showed phenotypic heterogeneity among family members, while both variations showed similarities in prepubertal phenotype, as well as in damage prediction and experimental decreases in transcriptional activity, but marked differences in structural consequence predictions. Finally the present study reinforces the concept of the wide variability in the clinical phenotype in affected 46,XY DSD patients. Fil: Perez Garrido, Natalia Isabel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Saraco, Nora Isabel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Marino, R.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Ramirez, P.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Ciaccio, Marta Graciela Cristina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Costanzo, M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Guercio, Gabriela Viviana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Warman, M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Minini, L.. Universidad de la República. Facultad de Ciencias; Uruguay Fil: Portillo Ledesma, S.. Universidad de la República. Facultad de Ciencias; Uruguay Fil: Rivarola, Marco Aurelio. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Coitiño, E. L.. Universidad de la República. Facultad de Ciencias; Uruguay Fil: Belgorosky, Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina

Background/Aims: Splicing CYP19 gene variants causingaromatase deficiency in 46,XX disorder of sexual development(DSD) patients have been reported in a few cases. Amisbalance between normal and aberrant splicing variants was proposed to explain spontaneous pubertal breast developmentbut an incomplete sex maturation progress. Theaim of this study was to functionally characterize a novelCYP19A1 intronic homozygote mutation (IVS9+5G>A) in a46,XX DSD girl presenting spontaneous breast developmentand primary amenorrhea, and to evaluate similar splicing variant expression in normal steroidogenic tissues. Methods:Genomic DNA analysis, splicing prediction programs,splicing assays, and in vitro protein expression and enzymeactivity analyses were carried out. CYP19A1 mRNA expressionin human steroidogenic tissues was also studied. Results:A novel IVS9+5G>A homozygote mutation was found.In silico analysis predicts the disappearance of the splicingdonor site in intron 9, confirmed by patient peripheral leukocytecP450arom and in vitro studies. Protein analysisshowed a shorter and inactive protein. The intron 9 transcriptvariant was also found in human steroidogenic tissues.Conclusions: The mutation IVS9+5G>A generates a splicingvariant that includes intron 9 which is also present in normalhuman steroidogenic tissues, suggesting that a misbalancebetween normal and aberrant splicing variants might occurin target tissues, explaining the clinical phenotype in the affectedpatient. Fil: Saraco, Nora Isabel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Nesi Franca, Suzana. Universidade Federal do Paraná; Brasil Fil: Sainz, Romina Belén. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría ; Argentina Fil: Marino, Roxana Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría ; Argentina Fil: Marques Pereira, Rosana. Universidade Federal do Paraná; Brasil Fil: La Pastina, Julia. Universidade Federal do Paraná; Brasil Fil: Perez Garrido, Natalia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría ; Argentina Fil: Sandrini, Romolo. Universidade Federal do Paraná; Brasil Fil: Rivarola, Marco Aurelio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría ; Argentina Fil: Lacerda, Luiz de. Universidade Federal do Paraná; Brasil Fil: Belgorosky, Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría ; Argentina

Context: Aromatase is the key enzyme for estrogen biosynthesis and is encoded by the CYP19A1 gene. Since 1991, several molecular CYP19A1 gene alterations associated with aromatase deficiency have been described in both sexes. Objective: The objective of the study was to detect CYP19A1 mutations in five aromatasedeficient 46, XX patients, to describe the clinical follow-up from birth to puberty and to perform haplotype analysis associated with the high-frequency c.628G>A splice mutation in Argentinean patients. Design: The design of the study was the sequencing of the coding and flanking intronic regions of the CYP19A1 gene in all patients and parents. Haplotype analysis of patients carrying the c.628G>A mutation was also performed. Patients: Clinical and biochemical findings in five new cases and one previously reported female aromatase-deficient patient (46, XX) are described. All patients presented with ambiguous genitalia at birth. Congenital adrenal hyperplasia due to 21-hydroxylase deficiency as well as other steroidogenic defects were ruled out. Results: Phenotypic variability among the affected patients was found during follow-up. Direct sequencing of the CYP19A1 gene from genomic DNA revealed one novel mutation (c.574C>T) in two patients. In silico analysis predicted the c.574C>T mutation to be probably damaging. Four of six nonrelated patients presented with the c.628G>A splice mutation. Haplotype analysis showed that the c.628G>A splice mutation is associated with the same haplotype in our population. Conclusions: Increased knowledge on phenotypical variability found in female aromatase-deficient patients is useful to improve the detection rate in this disorder. In our population, a genetic founder defect has probably contributed to an increase in the incidence of the c.628G>A splice mutation. Fil: Marino, Roxana Marcela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Garrido, Natalia Perez. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Costanzo, Mariana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Guercio, Gabriela Viviana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Juanes, Matías Hernan. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rocco, Carlos Alberto. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ramirez, Pablo. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Warman, Diana M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Ciaccio, Marta. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Pena, Gladys. Hospital Infantil Municipal de Cordoba; Argentina Fil: Feyling, José García. Hospital Regional de Concepcion; Argentina Fil: Miras, Mirta Beatriz. Hospital de Ninos de la Santisima Trinidad; Argentina Fil: Rivarola, Marco Aurelio. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Saraco, Nora Isabel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

The expression of aromatase, estrogen receptor alpha (ERalpha) and beta (ERbeta), androgen receptor (AR), and cytochrome P-450 side chain cleavage enzyme (cP450scc) was studied in prepubertal testis. Samples were divided in three age groups (GRs): GR1, newborns (1- to 21-d-old neonates, n = 5); GR2, postnatal activation stage (1- to 7-mo-old infants, n = 6); GR3, childhood (12- to 60-mo-old boys, n = 4). Absent or very poor detection of ERalpha by immunohistochemistry in all cells and by mRNA expression was observed. Leydig cells (LCs) of GR1 and GR2 showed strong immunostaining of aromatase and cP450scc but weak staining of ERbeta and AR. Interstitial cells (ICs) and Sertoli cells (SCs) expressed ERbeta, particularly in GR1 and GR2. Strong expression of AR was found in peritubular cells (PCs). For all markers, expression in GR3 was the weakest. In germ cells (GCs), i.e. gonocytes and spermatogonia, aromatase and ERbeta were immunoexpressed strongly whereas no expression of ERalpha, AR, or cP450scc was detected. It is proposed that in newborn and infantile testis, testosterone acting on PCs might modulate infant LC differentiation, whereas the absence of AR in SCs prevents development of spermatogenesis. The role of estrogen is less clear, but it could modulate the preservation of an adequate pool of precursor LCs and GCs.

Large cell calcifying Sertoli cell tumors (LCCSCT) are associated with Carney complex and Peutz-Jeghers syndrome. The mechanisms linking these 2 genetic defects to the genesis of this tumor are obscure. Studies of CYP19 (aromatase) and transforming growth factor (TGF)–β1 messenger RNA (mRNA) abundance, estrogen receptor (ER), TGFβ1, and TGFβ type II receptor (R) immunochemistry were carried out in the testis of a patient with this tumor to gain information on possible mechanisms of cell tumor development. Testicular tissue of a prepubertal patient, collected at gonadectomy, was separated into 2 macroscopically distinct fractions: tumoral nodules (Tu) and extratumoral, normal-looking testicular tissue (ExTu). The patient was a 9.5-year-old boy with a 5-year history of bilateral gynecomastia (Tanner stage 4), no pubic hair, incipient genital development, and bilateral testicular nodules. Multiple pigmented lesions of the skin were present. Bilateral mammectomy and gonadectomy was performed. RNA was extracted from Tu and ExTu for semiquantitative reverse transcriptase–polymerase chain reaction of CYP19 and TGFβ1. Protein expression of ER, TGFβ1, and TGFβ type II R in Tu and ExTu was detected by immunohistochemistry. Cell proliferation was estimated by Ki-67 antigen immunochemistry and apoptosis using a modified TUNEL assay. Mean expression of aromatase and TGFβ1 mRNAs in Tu was 6- and 2.3-fold higher than in ExTu, respectively ( P < 0.05). Tumoral cells exhibited ER staining with a predominant extra-nuclear localization. Positive staining of Sertoli cells in Tu was higher than in ExTu. TGFβ1 immunostaining of the interstitial cells in Tu was higher than in ExTu. TGFβ type II R immunostaining was detected in most Sertoli and interstitial cells, but intensity in ExTu was lower than in Tu. No significant difference was detected in the proliferation index, but in Tu, the percentage of Sertoli cells in apoptosis (1.4%) was significantly lower ( P < 0.01) than in ExTu (14.0%). The following hypothesis is proposed. The congenital gene defects of Carney complex or of Peutz-Jeghers syndrome might trigger a cascade of intracellular events that leads to overexpression of aromatase in Sertoli cells, favoring the development of a LCCSCT. At some point in the evolution of the disease, a mutational event might induce a higher expression of the ER. Also, TGFβ1 protein expression is increased in neighboring cells. In this environment, TGFβ1 might switch from tumor suppressor to oncogenic factor and along with estrogen-ER complexes, might favor tumor progression by inhibiting apoptosis.

Background: The serum GH cut-off value for pharmacological tests of GH secretion (PhT GH) depends on the type of test and also on the method used for determining serum GH. Cut-off serum GH values as different as 5–10 ng/ml, have been reported, and have been validated biochemically. We have used the growth velocity (GV)-standard deviation score (SDS) during the first year of treatment with rhGH to validate these cut-offs on a biological basis. Methods: Fifty pre-pubertal patients with short stature (height ≤–2 SDS and GV ≤–1.2 SDS) were studied. GH deficiency (GHD) was diagnosed in 39 patients, on the basis of clinical and auxological parameters and on the serum concentration of IGF-1, and non-GHD in the other 11 patients. Two PhT GH (arginine and clonidine) were carried out in the 50 patients. Serum GH was determined by two different methods: one detecting most of serum GH isoforms, named Total GH (HGH Bio-Tech, MAIA Clone), and another one, only detecting the 22 kDa GH, named 22K GH (GH-22K IFMA, Wallac). Results: Basal data: all patients with GHD and with non-GHD had maximal serum GH response (MaxR) values below and above the cut-off, respectively, for the serum Total GH and 22K GH. The mean 22K GH/Total GH ratio was similar to previous publications. Post-rhGH treatment data: the two groups improved their height SDS during the first year of treatment, particularly patients with GHD. A receiver-operator curve was used to define the best threshold for post-treatment GV-SDS that separates GHD from non-GHD patients. This value was 1.91 GV-SDS. A negative correlation between first year treatment GV-SDS and pre-treatment serum GH MaxR was found for the two assays (p < 0.001). Then, the best cut-off GV-SDS, previously calculated with the receiver-operator curve (1.91 SDS) was used to interpolate the corresponding serum GH values, as determined by the two methods. For Total GH, the value was 10.8 ng/ml, and for 22K GH, it was 5.4 ng/ml. Conclusion: The cut-off values calculated by biological means to separate GHD from non-GHD were remarkably similar to those calculated biochemically (10.0 and 4.8 ng/ml, respectively) for Total and 22K GH. This is a biological validation for using different cut-off values, appropriate for each assay, to diagnose GHD.

IGF-1, IGF-2, and type 1 IGF receptor (IGF-R1) mRNA expression and immunolocalization and cell proliferation index were studied in human adrenals from early infancy to late puberty. Adrenals were obtained from transplantation donors or from necropsies of endocrinologically normal subjects. Subjects were divided into three age groups: group 1

Context: 3βHSD2 is a bifunctional microsomal NAD+-dependent enzyme crucial for adrenal and gonad steroid biosynthesis, converting Δ5-steroids to Δ4-steroids. 3βHSD2 deficiency is a rare cause of congenital adrenal hyperplasia caused by recessive loss-of-function HSD3B2 mutations. Objective: The aim was to define the pathogenic consequences of a novel missense mutation in the HSD3B2 gene. Patient: We report a 7-month-old 46,XX girl referred because of precocious pubarche and postnatal clitoromegaly. Hormonal profile showed inadequate glucocorticoid levels, increased 17OHP and renin levels, and very high DHEAS levels, suggestive of compensated nonsalt-losing 3βHSD2 deficiency. Design and Results: Direct sequencing revealed a novel, homozygous, pG250V HSD3B2 mutation. In vitro analysis in intact COS-7 cells showed impaired enzymatic activity for the conversion of pregnenolone to progesterone and dehydroepiandrosterone to androstenedione (20% and 27% of WT at 6 h, respectively). G250V-3βHSD2 decreased the Vmax for progesterone synthesis without affecting the Km for pregnenolone. Western blot and immunofluorescence suggested that p.G250V mutation has no effect on the expression and intracellular localization of the mutant protein. Molecular homology modeling predicted that mutant V250 affected an L239-Q251 loop next to a β-sheet structure in the NAD+-binding domain. Conclusions: We identified a novel p.G250V mutation of HSD3B2 which causes an incomplete loss of enzymatic activity, explaining the compensated nonsalt loss phenotype. In vitro and in silico experiments provided insight into the structure-function relationship of the 3βHSD2 protein suggesting the importance of the L239-Q251 loop for the catalytic activity of the otherwise stable 3βHSD2 enzyme. Fil: Baquedano, María Sonia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Ciaccio, Marta. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Marino, Roxana Marcela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Perez Garrido, Natalia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Ramirez, Pablo. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Maceiras, Mercedes. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Turjanski, Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Defelipe, Lucas Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina Fil: Rivarola, Marco Aurelio. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Background Children born small for gestational age (SGA) experience higher rates of morbidity and mortality than those born appropriate for gestational age. In Latin America, identification and optimal management of children born SGA is a critical issue. Leading experts in pediatric endocrinology throughout Latin America established working groups in order to discuss key challenges regarding the evaluation and management of children born SGA and ultimately develop a consensus statement. Discussion SGA is defined as a birth weight and/or birth length greater than 2 standard deviations (SD) below the population reference mean for gestational age. SGA refers to body size and implies length-weight reference data in a geographical population whose ethnicity is known and specific to this group. Ideally, each country/region within Latin America should establish its own standards and make relevant updates. SGA children should be evaluated with standardized measures by trained personnel every 3 months during year 1 and every 6 months during year 2. Those without catch-up growth within the first 6 months of life need further evaluation, as do children whose weight is ≤ -2 SD at age 2 years. Growth hormone treatment can begin in SGA children > 2 years with short stature (< -2.0 SD) and a growth velocity < 25th percentile for their age, and should continue until final height (a growth velocity below 2 cm/year or a bone age of > 14 years for girls and > 16 years for boys) is reached. Blood glucose, thyroid function, HbA1c, and insulin-like growth factor-1 (IGF-1) should be monitored once a year. Monitoring insulin changes from baseline and surrogates of insulin sensitivity is essential. Reduced fetal growth followed by excessive postnatal catch-up in height, and particularly in weight, should be closely monitored. In both sexes, gonadal function should be monitored especially during puberty. Summary Children born SGA should be carefully followed by a multidisciplinary group that includes perinatologists, pediatricians, nutritionists, and pediatric endocrinologists since 10% to 15% will continue to have weight and height deficiency through development and may benefit from growth hormone treatment. Standards/guidelines should be developed on a country/region basis throughout Latin America.

Meta-analysis has shown a modest improvement in first-year growth response to recombinant human GH (r-hGH) for carriers of the exon 3-deleted GH receptor (GHRd3) polymorphism but with significant interstudy variability. The associations between GHRd3 and growth response to r-hGH over 3 years in relation to severity of GH deficiency (GHD) were investigated in patients from 14 countries. Treatment-naïve pre-pubertal children with GHD were enrolled from the PREDICT studies (NCT00256126 and NCT00699855), categorized by peak GH level (peak GH) during provocation test: ≤4 μg/l (severe GHD; n=45) and >4 to n=49) and genotyped for the GHRd3 polymorphism (full length (fl/fl, fl/d3, d3/d3). Gene expression (GE) profiles were characterized at baseline. Changes in growth (height (cm) and SDS) over 3 years were measured. There was a dichotomous influence of GHRd3 polymorphism on response to r-hGH, dependent on peak GH level. GH peak level (higher vs lower) and GHRd3 (fl/fl vs d3 carriers) combined status was associated with height change over 3 years (P

Programmed cell death and proliferation are evolutionary conserved processes that play a major role during normal development and homeostasis. In the testis, during the fetal and newborn periods, they might determine final adult size and fertility potential. In the present study, we have measured the relative number of testicular cells in apoptosis and in active proliferation in the seminiferous cords and in the interstitium, at different age periods of prepubertal testicular development in humans. Testes from 44 prepubertal subjects without endocrine and metabolic abnormalities were collected at necropsy. They were divided in three age groups (Gr): Gr 1, newborn (1- to 21-d-old neonates), n = 18, mean (+/-SD) age 0.3 +/- 0.23 months; Gr 2, post natal activation (1- to 6-month-old infants), n = 13, mean age 3.93 +/- 1.90 months; and Gr 3, early childhood period (1- to

In girls, but not in boys, pronounced adrenarche and precocious pubarche along with ovarian hyperandrogenism have been related to insulin resistance and reduced fetal growth. However, insulin secretion is increased during puberty in normal boys. The aim of this study was to analyze the possible implication of changes in the GH/IGF-I axis and in insulin sensitivity for the regulation of adrenal androgen secretion of normal prepubertal and adolescent boys. Fifty-six normal boys were divided into the following groups (Gr): Gr1, prepuberty (testicular volume

Background: IGF1R gene mutations have been associated with varying degrees of intrauterine and postnatal growth retardation, and microcephaly. Objective To identify and characterize IGF1R gene variations in a cohort of 28 Argentinean children suspected of having IGF-1 insensitivity, who were selected on the basis of the association of pre/postnatal growth failure and microcephaly. Methods The coding sequence and flanking intronic regions of IGF1R gene were amplified and directly sequenced. Functional characterization was performed by two in vitro assays: 1) [Methyl-3H] thymidine incorporation into DNA in fibroblast cell primary cultures from patients and controls treated with IGF-1 for 16-24 h. 2) PI3K/Akt pathway was evaluated with phospho-Akt (Ser473) STAR ELISA Kit (Millipore) in fibroblast cultures from patients and controls stimulated with IGF-1 for 10 min. Prepubertal clinical and GH-IGF-1 axis evaluation was followed up. Results We identified three novel heterozygous missense mutations in three unrelated patients, de novo p.Arg1256Ser, de novo p.Asn359Tyr and p.Tyr865Cys. In control cells, proliferation assay showed that IGF-1 significantly induced DNA synthesis at 20 h and Akt phosphorylation assay that it significantly stimulated phosphorylation after 10 min (P < 0·05 by anova and Bonferroni Tests). However, no significant increase was observed in any of the three patient fibroblasts in both functional studies. GH therapy growth response in two patients was inconsistent. Conclusion These variations led to failure of the IGF1R function causing pre- and postnatal growth retardation and microcephaly. Microcephaly should be considered in the evaluation of SGA patients, because it seems to favour the frequency of detection of IGF1R mutations. Fil: Juanes, Matías Hernan. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Guercio, Gabriela Viviana. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Marino, Roxana Marcela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Berensztein, Esperanza Beatriz. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Warman, Diana Mónica. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Ciaccio, Marta. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Gil, Silvia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Bailez, Marcela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Rivarola, Marco Aurelio. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

In blood, circulating IGFs are bound to six high-affinity IGFBPs, which modulate IGF delivery to target cells. Serum IGFs and IGFBP-3, the main carrier of IGFs, are upregulated by GH. The functional role of serum IGFBP-3-bound IGFs is not well understood, but they constitute the main reservoir of IGFs in the circulation. We have used an equation derived from the law of mass action to estimate serum IGFBP-3-bound IGF-I and IGFBP-3-bound IGF-II, as well as serum free IGF-I and free IGF-II, in 129 control children and adolescents (48 girls and 81 boys) and in 13 patients with GHD. Levels of serum total IGF-I, total IGF-II, IGFBP-1, IGFBP-2 and IGFBP-3 were determined experimentally, while those of IGFBP-4, IGFBP-5 and IGFPB-6, as well as the 12 affinity constants of association of the two IGFs with the six IGFBPs, were taken from published values. A correction for in vivo proteolysis of serum IGFBP-3 was also considered. In controls, serum total IGF-I, total IGF-II, IGFBP-3, IGFBP-3-bound IGF-I, IGFBP-3-bound IGF-II and free IGF-I increased linearly with age, from less than 1 to 15 years, in the two sexes. The concentrations of serum free IGF-I and free IGF-II were approximately two orders of magnitude below published values, as well as below the affinity constant of association of IGF-I with the type-1 IGF receptor. Therefore, it is unlikely that these levels can interact with the receptor. In the 13 patients with GHD, mean (+/- SD) SDS of serum IGFBP-3-bound IGF-I was -2.89 +/- 0.97. It was significantly lower than serum total IGF-I, free IGF-I or IGFBP-3 SDSs (-2.35 +/- 0.83, -1.12 +/- 0.78 and -2.55 +/- 1.07, respectively, p = 0.0001). The mean SDS of serum total IGF-II, IGFBP-3-bound IGF-II and free IGF-II were -1.25 +/- 0.68, -2.03 +/- 0.87 and 0.59 +/- 1.10, respectively, in GHD. In control subjects, 89.8 +/- 4.47% of serum total IGF-I and 77.3 +/- 9.4% of serum total IGF-II were bound to serum IGFBP-3. In patients with GHD, the mean serum IGFBP-3-bound IGF-I and IGFBP-3-bound IGF-II were 8.63 +/- 8. 53 and 19.1 +/- 14.7% below the respective means of control subjects (p0.02). In conclusion, in GHD there was a relative change in the distribution of serum IGFs among IGFBPs, due to the combined effects of the decrease in both total IGF-I and IGFBP-3. As a result, serum IGFBP-3-bound IGF-I and IGFBP-3 bound IGF-II, the main reservoirs of serum IGFs, were severely affected. This suggests that the decrease in serum IGFPB-3-bound IGF-I and IGFBP-3-bound IGF-II might have a negative effect for growth promotion and other biological effects of IGF-I and IGF-II. Finally, the estimation of serum IGFBP-3-bound IGF-I, or the percentage of total IGF-I and IGF-II bound to IGFBP-3, might be useful markers in the diagnosis of GHD.

Vitamin D (Vit D) is well recognized as an immunomodulator [...] Fil: Zaidman, Verónica E.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Maceiras, Mercedes. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Lazzati, Juan Manuel. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Kutasz, Ezequiel P.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: D’ Isa, Gabriela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Chilleli, Carla. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Tau, Cristina. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Viterbo, Gisela. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Rivarola, Marco Aurelio. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Chaler, Eduardo A.. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina

StAR facilitates cholesterol entry into the mitochondria as part of the transduceosome complex. Recessive mutations in the gen STAR cause classic and nonclassic congenital lipoid adrenal hyperplasia. The aim of the study was to analyze the molecular consequences of a novel heterozygous STAR mutation in a 46,XY patient with ambiguous genitalia and adrenal insufficiency. We found a de novo heterozygous IVS-2AG STAR mutation and the reported heterozygous p.G146A SF1 polymorphism with normal CYP11A1, FDXR, FDX1, VDAC1 and TSPO genes. RT-PCR and sequencing from patient's testicular RNA showed a -exon2 transcript and the wild-type (WT) transcript. Both 37 kDa precursor and 30 kDa mature protein were detected in COS-7 cell transfected with mutant and WT plasmids. Immunofluorescence showed almost no co-localization of mitochondria and mutant protein (delta22-59StAR). Delta22-59StAR activity was 65±13% of WT. Cotransfection with WT and delta22-59StAR plasmids reduced WT activity by 62.0% ± 13.9. Novel splice-junction heterozygous STAR mutation (IVS-2AG) resulted in the in-frame loss of amino acids 22 to 59 in the N-terminal mitochondrial targeting signal. A misfolded p.G22_L59delStAR might interfere with WT StAR activity by blocking the transduceosome complex, causing an autosomal dominant form of StAR deficiency, explaining the clinical phenotype.

Fil: Juanes, Matias Hernan. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatria "Juan P. Garrahan"; Argentina

Objective: Individual sensitivity to recombinant human GH (r-hGH) is variable. Identification of genetic factors contributing to this variability has potential use for individualization of treatment. The objective of this study was to identify genetic markers and gene expression profiles associated with growth response on r-hGH therapy in treatment-naïve, prepubertal children with GH deficiency (GHD) or Turner syndrome (TS). Design: A prospective, multicenter, international, open-label pharmacogenomic study. Methods: The associations of genotypes in 103 growth- and metabolism-related genes and baseline gene expression profiles with growth response to r-hGH (cm/year) over the first year were evaluated. Genotype associations were assessed with growth response as a continuous variable and as a categorical variable divided into quartiles. Results: Eleven genes in GHD and ten in TS, with two overlapping between conditions, were significantly associated with growth response either as a continuous variable (seven in GHD, two in TS) or as a categorical variable (four more in GHD, eight more in TS). For example, in GHD, GRB10 was associated with high response (≥Q3; P=0.0012), while SOS2 was associated with low response (≤Q1; P=0.006), while in TS, LHX4 was associated with high response (P=0.0003) and PTPN1 with low response (P=0.0037). Differences in expression were identified for one of the growth response-associated genes in GHD (AKT1) and for two in TS (KRAS and MYOD1). Conclusions: Carriage of specific growth-related genetic markers is associated with growth response in GHD and TS. These findings indicate that pharmacogenomics could have a role in individualized management of childhood growth disorders. Fil: Clayton, P.. Royal Manchester Children’s Hospital. Manchester Academic Health Sciences Centre; Reino Unido Fil: Chatelain, P.. Université Claude Bernard. Hopital Mère-Enfant. Département Pediatrie; Francia Fil: Tato, L.. Università degli Studi di Verona. Clinica Pediatrica; Italia Fil: Yoo, H. W.. University of Ulsan. College of Medicine. Asan Medical Center. Department of Pediatrics; Corea del Sur Fil: Ambler, G. R.. University of Sydney. The Children’s Hospital at Westmead; Australia Fil: Belgorosky, Alicia. Gobierno de la Ciudad de Buenos Aires. Hospital de Pediatría "Juan P. Garrahan"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Quinteiro, S.. Hospital Materno Infantil. Servicio de Pediatría Endocrino; España Fil: Deal, C.. University of Montreal. Department of Pediatrics; Canadá Fil: Stevens, A.. Royal Manchester Children’s Hospital. Manchester Academic Health Sciences Centre; Reino Unido Fil: Raelson, J.. Genizon BioSciences; Canadá Fil: Croteau, P.. Genizon BioSciences; Canadá Fil: Destenaves, B.. Merck Serono S.A.; Suiza Fil: Olivier, C.. Merck Serono S.A; Suiza

Little is known on the hormonal regulation of the early postnatal phase of Leydig cell activation in the human. Testosterone secretion by prepubertal testicular cells in culture was studied in two different age groups, 0-7-no-old (group 1) and 16-36-no-old (group 2) boys. A mixed cell preparation was isolated from testes collected at necropsy and maintained in culture for 6 d. Cells were cultured in serum-free medium in basal conditions and under the stimulation of human (h)LH, hFSH, or recombinant hGH, and the secretion of testosterone was determined on d 6 by RIA. In basal conditions, cells of group 1 secreted more testosterone (median 5.83 pmol/10 6 cells.d, n = 7) than cells of group 2 (median 1.73, n = 5), p < 0.05, reflecting the steroidogenic potential of the testes in vivo. Under hLH stimulation, cells of group 1 responded by increasing testosterone secretion significantly. Surprisingly, hFSH stimulation elicited a similar response in cells of group 1. Because FSH receptors are presumably located in Sertoli cells, it is concluded that these cells secreted a paracrine factor that stimulated testosterone secretion by Leydig cells. On the other hand, recombinant hGH also stimulated the secretion of testosterone by cells of group 1. Recombinant hGH could have interacted with either GH or prolactin receptors of testicular cells. Cells of group 2 did not respond to any stimulus. Because serum levels of LH, FSH, GH, and prolactin are higher during the first months of life than later in childhood, it is possible that the early postnatal activation of the testis is under multiple pituitary hormone influence.

Hospital de Pediatr i a Prof. Dr. Juan P. Garrahan, Combate de los Pozos 1881, Ciudad Autonoma de Buenos Aires, CP 1245, Argentina, Phone: +54 11 43084300, Fax: +54 11 43086700, mE- ail: echaler@yahoo.com Juan M. Lazzati, Mercedes Maceiras, Marco A. Rivarola and Alicia Belgorosky: Hospital de Pediatr i a Prof. Dr. Juan P. Garrahan , Buenos Aires , Argentina Gabriela Ballerini, Mauro Frusti, Ignacio Bergada and Gabriela Ropelato: Hospital de Ni n os Ricardo Gutierrez , Buenos Aires , Argentina

In humans, steroidogenic factor 1 (NR5A1/SF-1) mutations have been reported to cause gonadal dysgenesis, with or without adrenal failure, in both 46,XY and 46,XX individuals. We have previously reported extreme within-family variability in affected 46,XY patients. Even though low ovarian reserve with preserved fertility has been reported in females harboring NR5A1 gene mutations, fertility has only been observed in one reported case in affected 46,XY individuals. A kindred with multiple affected members presenting gonadal dysgenesis was studied. Four 46,XY individuals presented severe hypospadias at birth, one of them associated with micropenis and cryptorchidism. The other 3 developed spontaneous male puberty, and 1 has fathered 5 children. Four 46,XX patients presented premature ovarian failure (one of them was not available for the study) or high follicle-stimulating hormone levels. Mutational analysis of the NR5A1 gene revealed a novel heterozygous mutation, c.938G→A, predicted to cause a p.Arg313Hys amino acid change. A highly conserved amino acid of the ligand-binding domain of the mature protein is affected, predicting abnormal protein function. We confirm that preserved fertility can be observed in patients with a 46,XY disorder of sex development due to heterozygous mutations in the NR5A1 gene.

Establishment of reliable reference intervals remains valuable for confirming validity and advancing standardization across methods and populations. Moreover, knowledge of the measurement uncertainty (U) and of the reference change value (RCV) has important applications in clinical chemistry.Starting from the information available in the laboratory data base (29,901 subjects) an initial selection was carried out by eliminating all subjects with a clinical or laboratory pathological report; data from 7581 0- to 20-year-old subjects (53.87% girls) remained in the study. These subjects, divided into nine age groups, were used to define reference distribution percentiles (2.5th, 50th and 97.5th) of serum thyrotropin (TSH), triiodothyronine (T3), thyroxine (T4), and free T4 (fT4), as well as U and RCV of these assays.In early infancy, T4 and fT4 values were higher than in the older age groups. Serum T4 95th percentile reference value, useful for the diagnosis of hyperthyroidism, was 142.9 in 20-year-old boys and 230.4 nmol/L in early infants and serum T3 95th percentile was 2.6 and 3.5 nmol/L, respectively, while fT4 2.5th percentile reference value, useful for the diagnosis of hypothyroidism, was 9.6 and 13.0 pmol/L, respectively. Serum TSH 97.5th percentile showed less age variation, 4.38–4.88 mIU/L. Performance of the four assays resulted in approximately 20% Us, reflecting simple and complex imprecision, trueness, analytical and functional sensitivity. RCV of serum TSH (58.6%) was larger than for thyroid hormones (28.3%–34.7%), probably due to the high biological variation of this hormone.We have established reference interval for TSH and thyroid hormones, as well as Us for assessing reliability of measurements, and RCVs to alert users on the presence of clinical significant changes.