Crecimiento físico de niños con hiperplasia suprarrenal congénita perdedora de sal durante los dos primeros años de vida en el Instituto Nacional de Salud del Niño / Physical growth in children with salt-wasting adrenal hyperplasia during their first two years of life in the Peruvian National Children's Health Institute

Objetivo: Describir el crecimiento físico de niños con hiperplasia suprarrenal congénita (HSC) perdedora de sal durante los dos primeros años de vida, evaluados en el Servicio de Endocrinología del Instituto Nacional de Salud del Niño (INSN), Lima-Perú. Materiales y métodos: Es un estudio observacional, descriptivo y retrospectivo. Se incluyeron 55 niños con HSC que tuvieron seguimiento en el Servicio de Endocrinología del INSN del 2000 al 2016; se recopilaron datos como peso y talla al nacer y cada 6 meses, edad al diagnóstico, dosis de hidrocortisona y fludrocortisona y velocidad de crecimiento. Resultados: Se analizaron 55 niños con HSC perdedora de sal siendo el diagnóstico más precoz en mujeres (mediana: 21 días) que en varones (mediana: 52 días). Al nacimiento, su longitud promedio fue 0,07 + 0,75 DE; a los 6 meses fue -1,67 + 1,33 DE con mayor compromiso en varones (-2,29 + 1,18 DE; p=0,022); a los 12 meses fue -1,84 + 1,27 DE, con recuperación a los 24 meses (-1,51 + 1,10 DE). La velocidad de crecimiento fue -1,03 + 1,62 DE y -0,89 + 1,06 DE en el en el primer y segundo año, respectivamente. Conclusiones: Los niños con HSC perdedora de sal que tuvieron seguimiento en el INSN, tuvieron menor longitud a los 6 y 12 meses de edad y lograron recuperarse a los 24 meses.

Objective: To describe physical growth features in children with salt-wasting congenital adrenal hyperplasia (CAH) during their first two years of life, in the Endocrinology Service of the Peruvian National Children's Health Institute (CHI) in Lima, Peru. Materials and Methods: This is a retrospective, observational, and descriptive study. Fifty-five children with CAH underwent follow-up in the Endocrinology Service of the CHI from 2000 to 2016; data such as body weight and height were collected at birth time and every six months, as well as age at diagnosis, hydrocortisone and fludrocortisone doses, and growth velocity. Results: Fifty-five children with salt-wasting CAH were assessed, the diagnosis was more promptly made in females (median: 21 days) compared to males (median: 52 days). At birth, their average length was 0.07 ± 0.75 SD; at 6 months it was -1.67 ± 1.33 SD, and male subjects were more affected (-2.29 ± 1.18 SD; p= 0.022); at 12 months, this parameter was -1.84 ± 1.27 SD, and recovery was observed at 24 months (-1.51 ± 1.10 SD). Growth velocity values were -1.03 ± 1.62 SD and -0.89 ± 1.06 SD in the first and second years of life, respectively. Conclusions: Children with salt-wasting CAH who were followed-up at CHI had shorter length at 6- and 12- months of age, and their recovered at 24-monbths.

Central diabetes insipidus: clinical profile that suggests organicity in Peruvian children: Lima - Peru 2001-2013.

BACKGROUND: Central diabetes insipidus (CDI) is a heterogeneous disease caused by arginine vasopressin deficiency; its management implies a profound understanding of the pathophysiology and the clinical spectrum. The aim of the study was to describe the clinical characteristics that indicate organicity in children and adolescents with central diabetes insipidus treated at the Department of Endocrinology from The Child Health's Institute during 2001 to 2013. METHODS: Cross-sectional, retrospective study. 79 cases of patients diagnosed with CDI (51 males and 28 females) from 1 month to 16 years of age were reviewed. For the descriptive analysis, measures of central tendency and dispersion were used; groups of organic and idiopathic CDI were compared using χ2-test and t-test. A p-value<0.05 was considered significant. RESULTS: The average age of patients was 8.1±4.2 years. Organic causes were intracranial tumors, 44 (55.7%), Langerhans cell histiocytosis (LCH), 11 (13.9%) and cerebral malformations in 7 (8.9%) patients, while the idiopathic group was 14 (17.7%) patients. Regarding clinical characteristics suggestive of organicity, headache (p=0.02) and visual disturbances (p=0.01) were found statistically significant. The anterior pituitary hormonal abnormalities were documented in 34 (52.3%) organic CDI patients. Furthermore, we did not find a significant difference in the average daily dose of desmopressin between patients with permanent vs. transitory CDI (0.81±0.65 vs. 0.59±0.62; p=0.363). CONCLUSIONS: The main clinical features suggestive of organicity in pediatric patients with central diabetes insipidus were headache and visual disturbances; furthermore, anterior pituitary hormonal abnormalities suggest an underlying organic etiology.

Resistencia a insulina en adolescentes obesos / Insulin resistance in obese adolescents

Introducción: La obesidad en niños y adolescentes es un problema de salud pública que se encuentra en incremento a nivel mundial, siendo conocida su relación con el desarrollo de alteraciones metabólicas como la diabetes mellitus tipo 2. Objetivos: Determinar la presencia de resistencia a la insulina en adolescentes obesos y no obesos según sexo, edad, estadio puberal y antecedentes familiares de alteración metabólica o enfermedad cardiovascular (ECV) explorando asociación y riesgo. Diseño: Estudio transversal, observacional y analítico. Lugar: Tres centros educativos de la zona urbana de Lima. Participantes: Adolescentes entre 10 y 17 años de edad. Intervención: Se estudió 69 adolescentes entre 10 y 17 años de edad, agrupados de acuerdo a la presencia de obesidad. El diagnóstico de obesidad fue definido por un índice de masa corporal (IMC) >95 percentil; 55,1 por ciento varones y 44,9 por ciento mujeres. Se empleó el modelo de evaluación homeostática para determinar la resistencia a insulina (HOMA-IR) y la función de la célula beta (HOMAû por cientoB) en ambos grupos. También se realizó determinaciones de lípidos mediante método enzimático y se aplicó una encuesta para buscar antecedentes familiares de obesidad, diabetes mellitus y enfermedad cardiovascular (ECV). El análisis estadístico se hizo mediante pruebas de correlación de Spearman y de comparación de medias con la prueba U de Mann- Whitney. Principales medidas de resultados: Insulina basal, colesterol total, triglicéridos, colesterol-VLDL, HOMA IR y HOMA por cientoB en adolescentes obesos y no obesos. Resultados: Se encontró que la insulina basal, el colesterol total, triglicéridos, colesterol-VLDL, HOMA IR y HOMA por cientoB fueron significativamente mayores (p<0,05) en el grupo de obesos. El HOMA-IR presentó una correlación inversa, débil, con el desarrollo puberal, particularmente en el sexo femenino (r=-0,486, p<0,05). Predominaron los antecedentes familiares de obesidad y ECV en el grupo de obesos (71,8 por ciento). Conclusiones: La presencia de resistencia a la insulina en adolescentes obesos se asocia a los antecedentes familiares de obesidad y ECV. Se sugiere el empleo del HOMA asociado a la identificación de dichos antecedentes en adolescentes obesos, a fin de incorporarlos a un programa de atención integral de orientación a un estilo de vida saludable.

Introduction: Obesity in children and adolescents is a public health problem that is increasing worldwide, being known its relation with the development of metabolic alterations like diabetes mellitus type 2. Objectives: To determine the presence of insulin resistance in obese and non obese adolescents according to sex, age, pubertal stage and presence of familial metabolic or cardiovascular disorders. Design: Cross-sectional observational and analytical study. Setting: Three Lima urban educational centers. Participants: Adolescents 10 to 17 year-old. Interventions: Sixty nine adolescents between 10 and 17 years old were divided in two groups according to the presence of obesity. Obesity was defined as body mass index >95th percentile, 55,1 per cent were male and 44,9 per cent female. Homeostatic model assessment was employed to determine insulin resistance (HOMA-IR) and beta cell function (HOMA per centB) in both groups. Lipid levels were measured by the enzymatic method and a questionnaire was applied to determine familial obesity, diabetes mellitus and cardiovascular disease. Spearman correlation and U Mann-Whitney for media comparison tests were employed. Main outcome measures: Basal insuline, total cholesterol, triglicerids, CLDL cholesterol, HOMA IR and HOMA per centB in obese and non obese adolescents. Results: Basal insulin, cholesterol, triglycerides, VLDL cholesterol, HOMA IR and HOMA per centB were significantly higher (p<0,05) in the obese group. HOMA ûIR showed a weak inverse correlation with Tanner stage in females. Cardiovascular disease and obesity predominated in the obese group families (71,8 per cent). Conclusions: The use of HOMA along with familial disorders identification in obese adolescents is recommended in order to incorporate them in a healthy lifestyle program.

Características clínicas y hormonales del síndrome de insensibilidad a andrógenos / Clínical and hormonal characteristics of androgen insensitivity syndrome

Objetivo: Estudiar las características clínicas y hormonales de pacientes portadores del síndrome de insensibilidad a andrógenos. Material y Métodos: Se han estudiado 20 casos de pacientes portadores del síndrome de insensibilidad a andrógenos atendidos en el servicio de Endocrinología del Instituto Especializado de Salud del Niño. Se aplicó los criterios de Quigley para evaluar el grado de ambigüedad sexual.Resultados: Se encontró 10/18 (55,55%) de casos de grado III, 4/18 (22,22%) de grado IV, 2/18 (11,11%) de grado V, 1/18 (5,55%) de grado VI y 1/18 (5,55%) de grado VII, estos dos últimos grados corresponden al fenotipo femenino (SIA completo). En los pacientes con formas de SIA incompleto se encontró relación T/DHT >17, lo que equivale a discreta falla en la 5α-reductasa, lo que no sucedió con los pacientes con SIA completo. Conclusiones: El síndrome de insensibilidad a andrógenos por mostrar diversos grados de ambigüedad sexual amerita estudios genéticos, hormonales, diagnóstico por imágenes y exploración quirúrgica que permitan una orientación en la determinación del género.

Objective: Assessment of the clinical and hormonal characteristics of patients with androgen insensitivity syndrome (AIS). Materials and methods: 20 cases of AIS were studied in the Endocrinology Unit of the Instituto Especializado del Salud del Niño (Institute of Child Health - Lima, Perú). Quigley criteria was used to assess ambiguous genitalia. Results: According this criteria the findings were the following: 10/18 (55,55%) of cases were stage III, 4/18 (22,22%) were stage IV, 2/18 (11,11%) were stage V, 1/18 (5,55%) were stage VI and 1/18 (5,55%) were stage VII. The last two stages had female phenotype (complete AIS). In patients with incomplete AIS the ratio testosterone/dihydrotestosterone was less than 17, showing a mild failure of 5α-reductasa. This finding was not present in the cases with complete AIS. Conclusions: Due to the different degrees of ambiguous genitalia, the patients with AIS need genetic, hormone, images studies and surgical exploration to have the necessary criteria to suggest the most adequate therapy for each case.

Serine protease mechanism-based mimics. Direct evidence for a transition state bridge proton in stable potentials.

We have synthesized 1-(2-hydroxyacetyl)piperidine-2-one (2) and 1-(2-hydroxyacetyl)azepan-2-one (3). Equilibrium (K(f)) between the free alcohol (open form) and the tetrahedral intermediate (cyclol) is readily established, and both forms are observed in the D(2)O (1)H NMR spectra of 2 and 3. Therefore, their interconversion can be considered as an almost thermoneutral non-identical one. Pseudo-first-order rate constants (k(obs)) were obtained by simulating the AB (1)H NMR system observed for the cyclol. By best fitting the experimental points of a k(obs) versus pD profile to the equation k(obs) = 0.5k(0r) + 0.5k(r) K(ac)/(K(ac) + [D(+)]) + 0.5k(f)K(ao)/(K(ao)+ [D(+)]), the parameters involved were obtained: rate constants of rupture and formation (k(0r) and k(0f) = K(f)k(0r)) catalyzed by water, rate constants of rupture (k(r)) and formation (k(f)) from the conjugated bases of the cyclol form and the open form, and their acidity equilibrium constants K(ac) and K(ao). The system studied mimics the serine alcohol attack on the peptide bond and its reverse reaction in serine protease enzymes. In fact, the reaction rates are similar or perhaps even faster than the ones obtained for enzymatic reactions. The results also show the participation of water molecules forming catalytic proton bridges in stable potentials with the two interconverted forms. The position change of the bridged proton is sensitive to lactam ring size, and it is manifested by considerable change in the pKa values of both cyclol and open forms. Other evidence such as kinetics, DeltaS degrees , DeltaS, and proton inventory experiments and semiempirical molecular calculations support this proposal.

Titanium dioxide photoinduced degradation of some pesticide/fungicide precursors.

Five-membered nitrogen heterocycles (pyrrole, imidazole and 1,2,4-triazole) have been degraded using titanium dioxide and simulated solar radiation at pH = 8. The degradations followed a simple Langmuir-Hinshelwood mechanism. Accordingly, the adsorption equilibrium constants K of the heterocycles on the titanium dioxide surface and the rate constants k of degradation of the heterocycle-catalyst adduct have been obtained experimentally. While the K values decrease with heterocycle pKa, the k values increase with increasing pKa. Therefore, apparently, the rate constant depends on the availability of the electron pair on nitrogen, but at the same time the electron pair repulsion induced by the negatively charged titanium dioxide surface at pH = 8 causes a reverse effect in the adsorption equilibrium constant. Only in the case of imidazole, where the adsorption equilibrium constant is low enough (K = 0.013 M(-1)), can the rate constant be approximated to a pseudo-first-order rate expression: k(obs) = Kk. In all other cases, k(obs) = Kk/(1 + K(heterocycle)).

Hydrolysis of cyclic phosphoramides. Evidence for syn lone pair catalysis.

Hydrolysis between 1.5 < pH < 4 of five and six membered cyclic phosphoramides has been followed by UV and 3'PNMR spectroscopy. The observed rates fit the equation: k(obs) = k(H2O) [H+]/([H+] + Ka) + k'(H2O), where k(H2O) and k'(H2O) are the pseudo first-order rate constants of water attack on the protonated phosphoramide and its unprotonated form, respectively, and Ka is the phosphoramide acidity equilibrium constant. Although, faster hydrolysis rates on the five membered ring are expected due to the energy released in going from a strained cyclic to a "strained free" trigonal-bipyramidal-pentacoordinated intermediate, with one of the cyclic nitrogens occupying the apical position. these compounds react slightly faster (k(H2O) values) but slower regarding the k'(H2O) values than the six membered analogs. The balance in reactivity is attributed to the additional stability obtained in the six membered cyclic compounds by a syn orientation of the two lone pairs of the cyclic nitrogen to the water attack. This stabilization does not exist in the five membered phospholidines since the water attack is perpendicular to the electron pairs of the cyclic nitrogen. In agreement with the incoming water orientation, the product ratios from the hydrolysis show that in the five membered rings the main product is the one produced by endocyclic cleavage; meanwhile, in the six membered cyclic phospholines the kinetic product is the one produced by exocyclic cleavage. The syn orientation of two electron pairs on nitrogen stabilizes the transition state of water approach to the phosphoramides by ca. 3 kcal mol(-1) when compared to the orthogonal attack.

Aplicación de sistemas oxidantes avanzados en el tratamiento de aguas residuales de la industria petrolera (Sistema Fenton) / Application of advanced oxidants systems in the treatment of sewage of the petroleum industry (Fenton system)

Se trataron contaminantes típicos de aguas residuales provenientes de las actividades de la industria patrolera con el sistema Fenton (H2O2/Fe2+) em condiciones de temperatura ambiente. Los contaminantes tratados, en concentraciones ambientalmente prejudiciales, fueron m-cresol, 2-clorofenol y metil-terbutil-éter (MTBE). Adicionalmente fueron tratadas con Fenton aguas contaminadas con gasolina reformulada, en las cuales se hizo el seguimiento de la degradación de MTBE, y de algunos compuestos aromáticos monocíclicos (benceno, tolueno, etilbenceno y xilenos) presentes. Asimismo se comprobó la eficiencia del sistema en el tratamiento de aguas contaminadas en la actividad de produción, y de un agua residual proveniente de un complejo petroquímico. En todos los casos se observó una avanzada mineralización de los contaminantes en tiempos de reacción relativamente cortos. Se determinaron las constantes cinéticas, a temperatura ambiente, en la degradaçción de los substratos m-cresol, 2-clorofenol y MTBE.