Identifying patient-related predictors of permanent growth hormone deficiency.

Objective: Isolated childhood growth hormone deficiency (GHD) can persist into adulthood, and re-testing at the transition period is needed to determine whether continued growth hormone therapy is indicated. Here, our objective was to identify predictors of permanent GHD. Design: Retrospective single-centre study of patients with childhood-onset GHD who were re-tested after adult height attainment. Methods: Auxological, clinical, laboratory, and MRI data throughout follow-up were collected. Results: We included 101 patients. At GH treatment initiation, age was 8.1 ± 0.4 years, height -2.25 ± 0.8, and BMI -0.27 ± 0.1 SDS. The 29 (28.7%) patients with persistent GHD had lower height SDS (-2.57 ± 0.1 vs. -2.11 ± 0.1, p<0.001) and mean GH peaks (8.4 ± 1.0 vs.13.2 ± 0.5 mIU/L, p<0.001) at GHD diagnosis; at adult height, they had lower IGF1 (232 ± 19.9 vs. 331 ± 9.1 ng/mL, p<0.001) and higher BMI SDS (-0.15 ± 0.27 vs. -0.73 ± 0.13, p<0.005). By multivariate analysis, the best predictive model included height and BMI SDS, both GH peaks, and MRI findings at diagnosis. Patients with height at diagnosis <-3 SDS had a 7.7 (95% IC 1.4-43.1, p=0.02) fold higher risk of persistent GHD after adjustment on BMI SDS. An abnormal pituitary region by MRI was the strongest single predictor (7.2 times, 95% CI 2.7-19.8) and after multivariate analysis adjustment for GH peaks and height SDS at diagnosis, the risk increased to 10.6 (1.8 - 61.3) times. Conclusions: Height <-3 SDS at GHD diagnosis and pituitary MRI abnormalities should lead to a high index of suspicion for persistent GHD.

Vitamin D status and obesity in children from Chile.

BACKGROUND: Vitamin D [25(OH)D] is essential for normal bone development and maintenance. Furthermore, its deficiency has been associated with obesity, cardiovascular diseases, insulin resistance, autoimmune diseases, and certain cancers. OBJECTIVE: To determine the incidence of serum 25(OH)D deficiency (<20 ng/ml) among apparently healthy Chilean children (4-14 years old) from three Chilean geographic areas during May-September 2018. MATERIALS AND METHODS: Serum 25(OH)D levels were measured by a competitive protein-binding ELISA assay in 1134 children, and correlations between serum 25(OH)D levels, BMI, and geographic area were calculated. Individuals were grouped according to their serum 25-hydroxyvitamin D levels (ng/ml): severe deficiency: <5; moderate deficiency: 5-10.9; mild deficiency: 11-20.9; insufficiency: 21-29.9 and sufficiency: 30-100. RESULTS: We found 80.4% of children had serum 25(OH)D deficiency, with 1.7% severe, 24.6% moderate, and 54.1% mild. In the three cities, the percentage of serum 25(OH)D deficit was increased when comparing overweight or obesity with a healthy weight. Additionally, an interaction effect was observed between geographic area, nutritional status, and serum 25(OH)D levels using the factorial ANOVA test (p = 0.038). In Antofagasta, there were more overweight children and also a higher percentage of children with VitD deficiency (<30 ng/ml) compared to Santiago or Concepción. CONCLUSION: This study revealed a high prevalence of serum 25(OH)D deficiency in children between 4 and 14 years old in Chile (80.4%) during May-September 2018. Obese and overweight children had the highest prevalence of serum 25(OH)D deficiency.

Differential effects of androgens and estrogens over cellular GH sensitivity in HEPG2 cells.

Testosterone and estrogen concentrations progressively increase during puberty, and in association with growth hormone (GH), lead to the increase in height velocity known as the pubertal growth spurt. Very limited information is available however, regarding the possible effects of sex steroids over GH cellular sensitivity. OBJECTIVE: To investigate the effects of different concentrations of testosterone, estradiol and dihydrotestosterone over the GH intracellular signaling pathway. METHODS: We evaluated the effects of these sex steroids on the nuclear phosphorylation of STAT5b and IGF-1 expression, in HEPG2 human hepatoma cells. In addition, we studied whether Tamoxifen (TAM), can modulate these effects. RESULTS: The highest concentration of T tested (10 ng/mL) co-incubated with a fixed concentration of GH (40 ng/mL) increased nuclear STAT5b phosphorylation compared with GH alone (1.34 ± 0.2 vs 0.6 ± 0.09 AU; *p < 0.05), as well as IGF-1 expression (0.6 ± 0.03 vs 0.32 ± 0.05 AU; *p < 0.05). This effect was not observed with lower concentrations of T tested (1 and 5 ng/mL). A similar increase in nuclear STAT5b phosphorylation was observed with the lowest concentration of E2 tested (20 pg/mL), co-incubated with the same fixed concentration of GH (3.6 ± 0.5 vs 1.28 ± 0.33 AU; *p < 0.05). This effect was also associated with an increase in IGF-1 expression (0.73 ± 0.02 vs 0.39 ± 0.04 AU; *p < 0.05). These results were not observed with higher concentrations of E2 tested (75 and 200 pg/mL). DHT at concentrations of 0.1, 0.25 and 0.5 ng/mL, co-stimulated with GH, did not change cytoplasmic STAT5b phosphorylation, nuclear STAT5b or IGF-1 expression. In addition, the co-incubation of TAM with the highest concentration of T tested (10 ng/mL) and GH (40 ng/mL) did not change cytoplasmic, nuclear pSTAT5 levels or IGF-1 expression. CONCLUSIONS: T and E2 potentiate the GH signaling pathway in a concentration-dependent fashion. The observation that the non-aromatizable androgen dihydrotestosterone does not stimulate this pathway, and that the effects of T are blocked with TAM, suggests that the effects of T over the GH signaling pathway appear to be mediated by estrogen.

Reproductive hormones during pubertal transition in girls with transient Thelarche.

CONTEXT: Transient thelarche (TT), that is, the appearance, regression and subsequent reappearance of breast buds, is a frequent phenomenon, but little is known about pubertal transition in these girls. OBJECTIVE: To describe pubertal progression, growth, genotypes, reproductive hormones and growth factors in girls with TT compared to those who do not present TT (non-TT). DESIGN: Retrospective analysis of a longitudinal population-based study. PATIENTS OR OTHER PARTICIPANTS: Girls (n = 508) of the Chilean Growth and Obesity cohort. MEASUREMENTS: Pubertal progression, reproductive hormones, follicle stimulating hormone (FSH) beta subunit/FSH receptor gene single nucleotide polymorphisms and growth. RESULTS: Thirty-seven girls (7.3%) were presented TT. These girls entered puberty by pubarche more frequently (51%) than girls with normal progression (non-TT; n = 471; 23%, P = .005). Girls with TT who were under 8 years old had lower androgens, anti-Müllerian hormone (AMH), luteinizing hormone (LH) and oestradiol (all P < .05) than older girls with TT. At the time of Tanner breast stage 2 (B2), girls with TT had higher androgens, LH, FSH, IGF1, LH, insulin and oestradiol (P < .01) than at the time of TT. TT girls were older at B2 (10.3 ± 1.1 vs. 9.2 ± 1.2 years, P < .001) and menarche (12.3 ± 0.8 vs. 12.0 ± 1.0 years, P = .040) than their counterparts (non-TT). No differences in anthropometric variables or FSHB/FSHR genotypes were detected. CONCLUSION: Transient thelarche is a frequent phenomenon that does not appear to be mediated by hypothalamic-pituitary-gonadal axis activation or by adiposity. Hormonal differences between earlier TT and later TT suggest that their mechanisms are different.

Desarrollo psicomotor y cortisol salival en niños que viven juntos a sus madres privadas de libertad / Psychomotor development and cortisol salivary levels in infants that live with their inmate mothers

INTRODUCCIÓN: En Chile el sistema penitenciario cuenta con un programa que permite que las madres privadas de libertad vivan con sus hijos menores de 2 años. Esta modalidad podría implicar que los niños estén más expuestos a condiciones de estrés y a mayor riesgo de retraso en su desarrollo psicomotor (DSM). OBJETIVO: Comparar el DSM y la concentración de cortisol en saliva de los niños que viven en la cárcel junto a sus madres y comparar los resultados con los observados en niños que no están bajo este régimen. SUJETOS Y MÉTODO: Estudio transversal en 42 lactantes, 12 de ellos hijos de madres reclusas en el centro penitenciario de Santiago (CPF), y 30 controles provenientes de un Centro de Salud Familiar de Atención Primaria (CESFAM). Se evaluó DSM de los lactantes mediante la encuesta ASQ-3 y se realizó medición de cortisol salival mediante radioinmunoensayo a los lactantes y madres. RESULTADOS: La mediana de cortisol salival de los hijos de madres del CPF y CESFAM fue de 2,3 ng/ml (IQR 1,1 a 2,7) y de 2,1 ng/ml (IQR 1,6 a 2,9) respectivamente. El cortisol materno fue 4,6 ng/ml (IQR 3,8 a 7,3) en el CPF y 3,7 ng/ml (IQR 2,4 a 4,7) en el CESFAM. El déficit del DSM fue 2,3% y 28,5% para los niños del CPF y del CESFAM, respectivamente, sin diferencia estadística (p = 0,06). CONCLUSIONES: No hubo diferencia en el DSM y tampoco en el cortisol salival entre los niños de ambos grupos.

INTRODUCTION: In Chile, the prison system has a program that allows inmate mothers to live with their children un der two years of age. This could imply that these children are more exposed to stress conditions and a higher psychomotor developmental delay (PDD) risk. OBJECTIVE: To compare the PDD and salivary cortisol concentrations (SCC) of children living in prison with their mothers and to compare the results with control children. SUBJECTS AND METHOD: Cross-sectional study in 42 infants, 12 of them are children of inmate mothers in the penitentiary center (CPF) of Santiago, and 30 controls from a Primary Care Family Health Center (CESFAM). PDD of infants was assessed through the ASQ-3 questionnaire and salivary cortisol was measured in infants and mothers using radioimmunoassay. RESULTS: The median salivary cortisol level of the children of CPF and CESFAM mothers was 2.3 ng/ ml (IQR 1.1 to 2.7) and 2.1 ng/ml (IQR 1.6 to 2, 9) respectively. Maternal cortisol was 4.6 ng/ml (IQR 3.8 to 7.3) in the CPF and 3.7 ng/ml (IQR 2.4 to 4.7) in the CESFAM. The PDD deficit was 2.3% and 28.5% for children from the CPF and the CESFAM respectively, without statistical difference (p = 0.06). CONCLUSIONS: There was no difference in the PDD and salivary cortisol between children of both groups.

Is There a Difference between Ultrasonographic (US) Uterine Changes of Oral Versus Transdermal (TD) 17ß Estradiol (17ß E2) in Girls with Turner Syndrome (TS)? Own Experience and Literature Review.

BACKGROUND: Among patients with Turner Syndrome (TS), premature ovarian failure is a main feature. Recently published consensus guidelines recommend that transdermal (TD) estradiol is the preferred route for estrogen replacement. Studies related to ultrasound (US) measurements during estrogen replacement in TS patients using estradiol (17ß E2) and correlating uterine growth with estrogen metabolites are limited. OBJECTIVES: To compare uterine morphology and hormonal changes depending on route of administration of 17ß E2 (oral vs. TD) in a small population of girls with TS. SUBJECTS: 11 hypogonadal girls with TS (mean (SE) age 14.5 ± 1.4 years; BMI -0.98 ± -1.0 SDS) who participated in a larger study on the effects of oral versus TD 17ß E2 agreed to do a sub-study on the effect of the form of 17ß E2 treatment on uterine size. METHODS: 17ß E2 was given orally or TD for 12 months, titrated to doses up to 2 mg orally or 100 µg TD to achieve normal estradiol levels. Subjects received monthly progesterone for 1 week for withdrawal bleeding. At baseline, 6 and 12 months, a pelvic ultrasound was performed while on estradiol only. RESULTS: Uterine morphology and endometrial thickness increased comparably in both groups. E2 concentrations were comparable at 12 months between both groups but E1 and E1S were lower in TD group at 12 months. CONCLUSIONS: According to our experience, in a group of TS patients randomized to oral vs TD 17ß E2 and monitored with trans-abdominal US, both groups achieved similar increases in uterine size comparable to normal women. To confirm our observation a larger sample and a longer evaluation period is needed.

Efecto de Estradiol y Testosterona sobre la activación de la vía JAK2/STAT5 inducida por hormona de crecimiento / Estradiol and Testosterone effect on the activation of the JAK2/STAT5 pathway induced by growth hormone

Abstract: Sex hormones play a major role during pubertal growth. Estradiol (E2) and testosterone (T) levels progressively increase during puberty and in the presence of growth hormone (GH), growth velocity increases. Understanding the interactions between sex hormones and GH, may optimize the treatment of pubertal children with growth disorders. The aim of our study was to investigate possible molecular mechanisms which might potentiate longitudinal growth during puberty due to E 2or T combined with GH. We evaluated the GH/JAK2/STAT5 signaling pathway in the human hepatoma cell line HEPG2. Our results suggest that sex hormones potentiate the GH signaling pathway in a dose dependent fashion. Relatively low concentrations of E 2associated with GH induce a substantial activation of the GH pathway, whereas relatively high concentrations of T associated with GH produce a similar effect. These findings are concordant with the physiology of the pubertal growth spurt, which is an early event in girls (when E 2 circulating levels are low), and a late event in boys (when T circulating levels are high).

Resumen: Las hormonas sexuales, modulan el crecimiento durante la pubertad. Los niveles de estradiol (E2) y testosterona (T) aumentan progresivamente durante la pubertad y en combinación con la hormona de crecimiento (GH), producen un incremento en la velocidad de crecimiento en este período conocido como el "estirón puberal". El estudio de la interacción entre las hormonas sexuales y la GH, es de gran importancia para optimizar el tratamiento de niños(as) con alteraciones del crecimiento durante la pubertad. El objetivo de nuestro estudio fue investigar los posibles mecanismos que podrían potenciar el crecimiento longitudinal durante la pubertad, en especial las interacciones entre E 2o T en combinación con GH. Se evaluó la activación de la vía de señalización GH/JAK2/STAT5 frente al estímulo combinado con estas hormonas en cultivos celulares de hepatoma humana HEPG2. Nuestros resultados sugieren que existe un efecto potenciador de las hormonas sexuales sobre la vía de señalización de GH. Observamos que concentraciones relativamente bajas de E2 junto con GH producen una clara activación de la vía de señalización para GH, mientras que concentraciones relativamente altas de T junto con GH producen una activación similar. Estos hallazgos son concordantes con la fisiología del estirón puberal, que es más precoz en niñas (cuando los niveles circulantes de E2 son bajos), y más tardíos en varones (cuando los niveles circulantes de T son altos).

Folate Transporters in Placentas from Preterm Newborns and Their Relation to Cord Blood Folate and Vitamin B12 Levels.

Folate deficiency during pregnancy has been related to low birth weight, preterm (PT) birth and other health risks in the offspring; however, it is unknown whether prematurity is related to low folate transport through the placenta due to altered expression of specific folate transporters. We determined placental expression (mRNA and protein concentrations by RT-qPCR and WB respectively) of specific folate transporters: RFC, PCFT/HCP1 and FOLR1 in chorionic (fetal) and basal (maternal) plates of placentas of PT pregnancies (PT, 32-36 weeks, n = 51). Term placentas were used as controls (T, 37-41 weeks, n = 47). Folates and vitamin B12 levels were measured by electrochemiluminescence in umbilical cord blood of newborns. FOLR1 mRNA expression was lower and protein concentration higher in PT placentas (both plates) relative to the control group (p <0.05). In addition, gestational age was positively correlated with mRNA expression (Rho = 0.7), and negatively with protein concentration (Rho = -0.7 for chorionic and -0.43 for basal plate). PCFT/HCP1 mRNA was lower in PT placentas, without changes in protein levels. RFC did not differ in PT placentas compared to controls. PT newborns presented higher cord blood folate level (p = 0.049) along with lower vitamin B12 concentration compared to controls (p = 0.037).In conclusion, placental FOLR1 mRNA was positively associated with gestational age. Conversely, FOLR1 protein concentrations along with folate/vitamin B12 ratio in cord blood were negatively associated with gestational age. Placental FOLR1 is likely the main placental folate transporter to the fetus in newborns.

[Severe vitamin D deficiency in children from Punta Arenas, Chile: Influence of nutritional status on the response to supplementation]. / Deficiencia severa de vitamina D en niños de Punta Arenas, Chile: influencia de estado nutricional en la respuesta a suplementación.

UNLABELLED: There is a high risk of vitamin D (VD) deficiency in the population of southern Chile that can be treated with VD supplements. Weight excess (WE) can influence the response to supplements. OBJECTIVES: To study the prevalence of VD deficiency and the effect of cholecalciferol (VD3) supplements in healthy children from Punta Arenas, Chile, and evaluate a possible association with nutritional status. METHODOLOGY: Demographic and anthropometric data, as well as laboratory assessment of serum 25-hidroxyvitamin D (25OHD) and other bone metabolism parameters were evaluated. After baseline evaluation, children were supplemented with VD3 1600 IU/day for one month, after which 25OHD was retested. RESULTS: Of the 108 children studied, 50% were boys, and had a mean age of 9.6±0.5 years. Nutritional assessment showed that 39% had normal weight, 46% were overweight, and 15% were obese. Median 25OHD was 10.9ng/ml: 96.3% had deficiency (<20ng/ml) and 3.7% insufficiency (20-29ng/ml). Severe deficiency was found in 62% (<12ng/ml). Baseline 25OHD was not affected by nutritional status. After supplementation, median 25OHD was 17.5ng/ml: 62% had deficiency, 36% insufficiency, and 2% sufficiency (>30ng/ml). Children with WE had a significantly lower increase in 25OHD than children with normal weight (5±5.5 vs. 7.7±4.9, p=03). Children with WE may require 32% higher VD dose than normal weight children to attain the same 25OHD concentration. CONCLUSIONS: Chilean schoolchildren from Punta Arenas have high prevalence of WE and VD deficiency, with a majority in the range of severe VD deficiency. WE interferes in the response to VD supplementation, leading to a lower increase in 25OHD.

[Insulin autoimmune syndrome: Report of two cases]. / Síndrome de hipoglicemia autoinmune: Primeros casos en Chile.

Insulin autoimmune syndrome (IAS) is characterized by spontaneous hypoglycemia with extremely high insulin levels and the presence of circulating autoantibodies against insulin, in patients who have never been exposed to exogenous insulin. We report two patients with the syndrome. A 36 years old male presenting with hypoglycemia in the emergency room had an oral glucose tolerance test showed basal and 120 min glucose levels of 88 and 185 mg/dl. The basal and 120 min insulin levels were 2,759 and 5,942 µUI/ml. The presence of an insulin secreting tumor was discarded. Anti-insulin antibodies were positive. He was successfully treated with a diet restricted in carbohydrates and frequent meals in small quantities. A 65 years old female presenting with hypoglycemia in the emergency room had the fasting insulin levels of 1,910 µUI/ml. No insulin secreting tumor was detected by images and anti-insulin antibodies were positive. The polyethylene glycol precipitation test showed a basal and after exposition insulin level 1,483 and 114 µUI/ml, respectively. She responded partially to diet and acarbose and required the use of prednisone with a good clinical response.

Hirsutism and oligomenorrhea are appropriate screening criteria for polycystic ovary syndrome in adolescents.

We evaluated the association of hirsutism and oligomenorrhea (persistent menstrual cycles > 45 days) as screening criteria for the detection of biochemical hyperandrogenism (BH) and polycystic ovaries (PCOM) during adolescence and determined which androgens, granulosa cell hormone, ultrasonographic parameters have the best association with polycystic ovary syndrome (PCOS). Hirsute girls with oligomenorrhea (N = 26 Hirs/Oligo group) and non-hirsute girls with regular cycles (N = 63, C group) were studied. Prevalence of BH and PCOM, diagnostic performance of androgens and ultrasound parameters for PCOS diagnosis were analyzed. BH and PCOM prevalence were higher in the Hirs/Oligo girls than in the C girls (76.9% versus 25.5%; 92.3% versus 33.3%, respectively; p < 0.0001). A complete PCOS phenotype (Hirs/Oligo with BH and PCOM) was observed in 73.1% of the Hirs/Oligo group. The presence of both BH and PCOM was observed in 7.9% of the C group. The parameters with the best diagnostic performance were free androgen index ≥6.1, testosterone ≥2.4 nmol/L, follicle number ≥12 and ovarian volume ≥10 ml anti-Müllerian hormone (AMH) exhibited a low diagnostic accuracy. Hirsutism and persistent menstrual cycle over 45 days are highly associated with BH and PCOM suggesting that the presences of both criteria are necessary for the diagnosis of PCOS during adolescence.

Síndrome de hipoglicemia autoinmune: Primeros casos en Chile / Insulin autoimmune syndrome: Report of two cases

Insulin autoimmune syndrome (IAS) is characterized by spontaneous hypoglycemia with extremely high insulin levels and the presence of circulating autoantibodies against insulin, in patients who have never been exposed to exogenous insulin. We report two patients with the syndrome. A 36 years old male presenting with hypoglycemia in the emergency room had an oral glucose tolerance test showed basal and 120 min glucose levels of 88 and 185 mg/dl. The basal and 120 min insulin levels were 2,759 and 5,942 μUI/ml. The presence of an insulin secreting tumor was discarded. Anti-insulin antibodies were positive. He was successfully treated with a diet restricted in carbohydrates and frequent meals in small quantities. A 65 years old female presenting with hypoglycemia in the emergency room had the fasting insulin levels of 1,910 µUI/ml. No insulin secreting tumor was detected by images and anti-insulin antibodies were positive. The polyethylene glycol precipitation test showed a basal and after exposition insulin level 1,483 and 114 µUI/ml, respectively. She responded partially to diet and acarbose and required the use of prednisone with a good clinical response.

Deficiencia severa de vitamina D en niños de Punta Arenas, Chile: influencia de estado nutricional en la respuesta a suplementación / Severe vitamin D deficiency in children from Punta Arenas, Chile: Influence of nutritional status on the response to supplementation

En población austral existe un alto riesgo de deficiencia de vitamina D (VD) que puede tratarse mediante suplementación nutricional. El exceso de peso (EP) podría afectar la respuesta a su suplementación. Objetivos: Estudiar la prevalencia de deficiencia de VD y el efecto de la suplementación con colecalciferol (VD3) en niños sanos de Punta Arenas, Chile, y evaluar la posible asociación con el estado nutricional. Metodología: Se obtuvieron datos demográficos, antropométricos y medición sérica de 25-hidroxivitamina-D (25OHD) y parámetros de metabolismo óseo. Luego se suplementó a los niños con VD3 1.600 UI/día por un mes y se reevaluó 25OHD sérica. Resultados: Se estudiaron 108 niños, 50% hombres, edad promedio 9,6 ± 0,5 años. Un 39% eran eutróficos, 46% con sobrepeso y 15% obesos. La mediana de 25OHD fue 10,9 ng/ml: 96,3% tenían deficiencia (< 20 ng/ml) y 3,7% insuficiencia (20 a 29 ng/ml). Se pesquisó deficiencia severa (< 12 ng/ml) en 62%. La concentración basal de 25OHD no varió según estado nutricional. Luego de la suplementación, la mediana de 25OHD fue 17,5 ng/ml: 62% con deficiencia, 36% insuficiencia y 2% suficiencia (> 30 ng/ml). Los niños con EP tuvieron un alza de 25OHD significativamente menor que niños eutróficos (5 ± 5,5 vs. 7,7 ± 4,9, p = 0,03). Niños con EP requerirían dosis de VD 32% mayores que niños eutróficos para lograr la misma concentración de 25OHD. Conclusiones: Niños escolares de Punta Arenas presentan alta prevalencia de EP, deficiencia de VD y la mayoría en rango de deficiencia severa. El EP interfiere en la respuesta a suplementación farmacológica, logrando menor alza de 25OHD.

There is a high risk of vitamin D (VD) deficiency in the population of southern Chile that can be treated with VD supplements. Weight excess (WE) can influence the response to supplements. Objectives: To study the prevalence of VD deficiency and the effect of cholecalciferol (VD3) supplements in healthy children from Punta Arenas, Chile, and evaluate a possible association with nutritional status. Methodology: Demographic and anthropometric data, as well as laboratory assessment of serum 25-hidroxyvitamin D (25OHD) and other bone metabolism parameters were evaluated. After baseline evaluation, children were supplemented with VD3 1600 IU/day for one month, after which 25OHD was retested. Results: Of the 108 children studied, 50% were boys, and had a mean age of 9.6 ± 0.5 years. Nutritional assessment showed that 39% had normal weight, 46% were overweight, and 15% were obese. Median 25OHD was 10.9 ng/ml: 96.3% had deficiency (< 20 ng/ml) and 3.7% insufficiency (20-29 ng/ml). Severe deficiency was found in 62% (< 12 ng/ml). Baseline 25OHD was not affected by nutritional status. After supplementation, median 25OHD was 17.5 ng/ml: 62% had deficiency, 36% insufficiency, and 2% sufficiency (>30 ng/ml). Children with WE had a significantly lower increase in 25OHD than children with normal weight (5 ± 5.5 vs. 7.7 ± 4.9, p = 03). Children with WE may require 32% higher VD dose than normal weight children to attain the same 25OHD concentration. Conclusions: Chilean schoolchildren from Punta Arenas have high prevalence of WE and VD deficiency, with a majority in the range of severe VD deficiency. WE interferes in the response to VD supplementation, leading to a lower increase in 25OHD.

Elevation of C-reactive protein during the luteal phase in healthy adolescents.

INTRODUCTION: Variations in inflammatory markers have been reported in adult women during the luteal phase, but whether these findings are observed during adolescence is unknown. We postulate that higher ultrasensitive C-reactive protein (usCRP) and lower 2-hydroxyestrone (2OHE) levels, an estrogen metabolite with cardioprotective actions, are present during the luteal phase in young women. AIM: To evaluate usCRP levels during the menstrual cycle and to determine its association with 2OHE and 16α-hydroxyestrone (16OHE) in adolescents. METHODS: Healthy postmenarcheal adolescents (N = 37) were studied during one menstrual cycle in follicular phase (FP) and luteal phase-like period (LP-L). RESULTS: Elevations in usCRP levels in the LP-L were observed in the entire group and in anovulatory cycles (1.9 ± 1.1 mg/L in FP to 2.5 ± 1.8 mg/L in LP-L; p < 0.0001). Increases in estrone, estradiol, free and bioavailable estradiol, testosterone, usCRP and 2OHE levels were observed in LP-L compared with FP (p < 0.01), with a borderline elevation in IFG-I levels (p = 0.06). CONCLUSIONS: We report an elevation of usCRP and 2OHE levels during the luteal phase in healthy adolescents. Elevations of this inflammatory marker in anovulatory adolescents without an increase in 2OHE may play a role in metabolic risks associated with chronic anovulation.

Leuprolide acetate-stimulated androgen response during female puberty.

BACKGROUND: A physiological increase in androgen levels occurs during adolescence. Measuring androgen concentrations is the best method to distinguish normal evolution processes from hyperandrogenic disorders. HYPOTHESIS: The increase in circulating androgens during puberty is inversely associated with insulin sensitivity in normal weight girls. OBJECTIVE: To assess circulating levels of ovarian androgens and anti-Müllerian hormone (AMH) at baseline and after GnRH analogue (GnRH-a) stimulation in normal pubertal girls across different Tanner stages. We also studied the association between this response and insulin sensitivity. DESIGN: Prospective study of healthy girls (6-12 years) from the local community (n = 63). METHODS: Tanner I (n = 23) subjects were assessed cross-sectionally, and Tanner II girls (n = 40) were evaluated every 6 months until they reached Tanner V. Early morning dehydroepiandrosterone sulphate (DHEA-S), AMH, sex hormone-binding globulin (SHBG), androstenedione, glucose and insulin levels were measured. A GnRH-a test (500 µg/m(2) ; sc) and oral glucose intolerance test (OGTT) were performed. Differences throughout puberty were evaluated. RESULTS: Basal and/or stimulated Testosterone DHEA-S and 17-hydroxyprogesterone (17OHP) were inversely associated with insulin sensitivity (WIBSI) from the beginning of puberty, whereas androstenedione was directly associated with gonadotrophins. AMH was inversely associated with basal and stimulated gonadotrophins and directly with insulin area under the curve (AUC) only in the early stages of puberty. 17OHP and testosterone responsiveness increased significantly during puberty in all subjects, whereas testosterone levels changed less consistently. This pattern of ovarian-steroidogenic response was most evident during mid- and late puberty. Moreover, during late puberty only, basal 17OHP, testosterone and DHEA-S were positively associated with gonadotrophins. CONCLUSION: In normal nonobese girls born appropriate for gestational age, androgen synthesis was associated with insulin sensitivity in early puberty and with LH only in late puberty.

IGF-IR signal transduction protein content and its activation by IGF-I in human placentas: relationship with gestational age and birth weight.

INTRODUCTION: The human placenta expresses the IGF-I and IGF-IR proteins and their intracellular signal components (IRS-1, AKT and mTOR). The aim of this study was to assess the IGF-IR content and activation of downstream signaling molecules in placentas from newborns who were classified by gestational age and birth weight. We studied placentas from 25 term appropriate (T-AGA), 26 term small (T-SGA), 22 preterm AGA (PT-AGA), and 20 preterm SGA (PT-SGA) newborns. The total and phosphorylated IGF-IR, IRS-1, AKT, and mTOR contents were determined by Western Blot and normalized by actin or with their respective total content. The effect of IGF-I was determined by stimulating placental explants with recombinant IGF-I 10-8 mol/L for 15, 30, and 60 minutes. RESULTS: The IGF-IR content was higher in T-SGA compared to T-AGA placentas, and the IRS-1 content was higher in PT-placentas compared with their respective T-placentas. The effect of IGF-I on the phosphorylated forms of IGF-IR was increased in T-SGA (150%) and PT-SGA (300%) compared with their respective AGA placentas. In addition, AKT serine phosphorylation was higher in PT-SGA compared to PT-AGA and T-SGA placentas (90% and 390% respectively). CONCLUSION: The higher protein content and response to IGF-I of IGF-IR, IRS-1, and AKT observed in SGA placentas may represent a compensatory mechanism in response to fetal growth restriction.

Hormonal profile and androgen receptor study in prepubertal girls with hypertrichosis.

BACKGROUND: Prepubertal hypertrichosis is a reportedly benign condition characterized by an excessive growth of vellous hair in non-androgen dependent areas of the body compared to the amount usually present in normal subjects of the same age, race and sex. Although this condition is usually considered idiopathic and regarded as benign, it may be very disturbing cosmetically, causing significant patient and parental anxiety. METHOD: We performed a hormonal and androgen receptor study in 42 prepubertal girls with hypertrichosis and 29 control girls from 2 to 8 years of age. Both groups underwent a determination of basal LH, FSH, 17OH progesterone, androstenedione, testosterone, estradiol and SHBG, abdominal ultrasound to assess ovarian morphology, and the number of androgen receptor CAG/GGC repeats in DNA obtained from peripheral leukocytes. RESULTS: The hypertrichosis score was higher in the cases compared to controls. Serum gonadotropins and sex steroids were similar in both groups, but SHBG was significantly lower in the girls with hypertrichosis (71.1 ± 2.9 vs 81.9 ± 3.0 nmol/L, p < 0.02). The distribution of shorter, larger and total alleles was not statistically different between cases and controls. The combined analysis of CAG/GGC, however, showed a significantly higher prevalence of the most androgen-sensitive haplotypes (1-2: <22CAG + 17/17GGC- < 14CAG + 17/18GGC) in girls with hypertrichosis compared to controls. CONCLUSIONS: We conclude that girls with hypertrychosis exhibit AR(s) with enhanced sensitivity, which may facilitate the growth of their body hair.

Phosphotyrosine phosphatases in GH-stimulated skin fibroblasts from children with idiopathic short stature.

AIM: Some cases of idiopathic short stature (ISS) may be caused by defects in the modulation of the negative feedback regulation of the growth hormone receptor (GHR)/ Janus kinase (JAK)2/signal transducers and activators of transcription (STAT)5 signaling pathway. The cytosolic tyrosine phosphatases, protein tyrosine phosphatase 1B (PTP1B) and Src homology 2 (SH2) domain-containing protein-tyrosine phosphatase-1 (SHP-1), the later which translocates to the nucleus after activation, interact with JAK2 in a GH-dependent manner. The possible contribution of PTP1B and SHP-1 to GH signaling in fibroblasts from ISS patients has not been studied. METHODS: We determined the basal protein content of PTP1B and SHP-1 in the presence of recombinant human GH (rhGH) for 24 h in skin fibroblast cultures, obtained from patients with ISS, and were compared with a normal height control children group. JAK2 activation was determined in both groups. RESULTS: JAK2 activation was delayed in fibroblasts from ISS patients compared to controls. Under basal conditions, the protein content of SHP-1 was lower in ISS, and after incubation with rhGH, it decreased in the non-nuclear and nuclear fraction of controls, but not in ISS patients. The protein content of PTP1B, however, increased in a similar fashion in fibroblasts from both ISS and control children. CONCLUSION: The delayed activation of JAK2 and the lack of response of SHP-1 after incubation with GH in fibroblasts from ISS patients, suggests that the growth retardation observed in some of these children may be mediated in part by this phosphotyrosine phosphatase.

[Effects of smoking on plasma antimüllerian hormone concentrations among infertile women]. / El hábito de fumar se asocia a baja concentración plasmática de hormona antimülleriana en mujeres infértiles.

BACKGROUND: Smoking may hamper female fertility, probably modifying ovarian reserve. Antimüllerian hormone (AMH) is an accurate marker for ovarian reserve. AIM: To look for an association between smoking status and plasma AMH concentration. PATIENTS AND METHODS: A cohort of 141 infertile women in a university setting in Santiago, Chile was studied. Demographic and smoking data, including the number of cigarettes smoked during the last week, were collected. A blood sample was obtained and kept frozen until determination of AMH by ELISA and follicle stimulating hormone (FSH) and estradiol at day three of the menstrual cycle, by radioimmunoanalysis. RESULTS: Thirty two participants smoked (23%). There were no significant differences in age, parity, body mass index, causes of infertility and day three FSH and estradiol between smokers and nonsmokers. According to a regression analysis, there was a significant decrease in AMH concentration with age and active cigarette smoking. A drop in AMH of -0.189 ng/mL with a unitary change in age and a decrease of -2.29 ng/mL when everything else remains constant, except the smoking status, were established (p < 0.001 and r2 = 0.134). However, no dose response was observed when the number of cigarettes smoked during the last week were introduced in the model. Furthermore, no significant association of plasma AMH with day three plasma FSH and estradiol concentrations was observed. CONCLUSIONS: Cigarette smoking is associated with decreased AMH plasma concentrations among infertile women. However there was no dose response relationship. The mechanisms underlying this association are unknown and further investigation is required.

El hábito de fumar se asocia a baja concentración plasmática de hormona antimülleriana en mujeres infértiles / Effects of smoking on plasma antimüllerian hormone concentrations among infertile women

Background: Smoking may hamperfemale fertility, probably modifying ovarian reserve. Antimüllerian hormone (AMH) is an accurate marker for ovarian reserve. Aim: To look for an association between smoking status and plasma AMH concentration. Patients and Methods: A cohort of 141 infertile women in a university setting in Santiago, Chile was studied. Demographic and smoking data, including the number of cigarettes smoked during the last week, were collected. A blood sample was obtained and kept frozen until determination of AMH by ELISA and follicle stimulating hormone (FSH) and estradiol at day three of the menstrual cycle, by radioimmunoanalysis. Results: Thirty two participants smoked (23%). There were no significant differences in age, parity, body mass index, causes of infertility and day three FSH and estradiol between smokers and nonsmokers. According to a regression analysis, there was a significant decrease in AMH concentration with age and active cigarette smoking. A drop in AMH of -0.189 ng/mL with a unitary change in age and a decrease of -2.29 ng/mL when everything else remains constant, except the smoking status, were established (p < 0.001 and r2 = 0.134). However, no dose response was observed when the number of cigarettes smoked during the last week were introduced in the model. Furthermore, no significant association ofplasma AMH with day three plasma FSH and estradiol concentrations was observed. Conclusions: Cigarette smoking is associated with decreased AMHplasma concentrations among infertile women. However there was no dose response relationship. The mechanisms underlying this association are unknown and further investigation is required.