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1.
Dalton Trans ; 42(45): 16049-55, 2013 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23945598

RESUMEN

We have revealed the fundamental mechanism of specific Cs(+) adsorption into Prussian blue (PB) in order to develop high-performance PB-based Cs(+) adsorbents in the wake of the Fukushima nuclear accident. We compared two types of PB nanoparticles with formulae of Fe(III)4[Fe(II)(CN)6]3·xH2O (x = 10-15) (PB-1) and (NH4)0.70Fe(III)1.10[Fe(II)(CN)6]·1.7H2O (PB-2) with respect to the Cs(+) adsorption ability. The synthesised PB-1, by a common stoichiometric aqueous reaction between 4Fe(3+) and 3[Fe(II)(CN)6](4-), showed much more efficient Cs(+) adsorption ability than did the commercially available PB-2. A high value of the number of waters of crystallization, x, of PB-1 was caused by a lot of defect sites (vacant sites) of [Fe(II)(CN)6](4-) moieties that were filled with coordination and crystallization water molecules. Hydrated Cs(+) ions were preferably adsorbed via the hydrophilic defect sites and accompanied by proton-elimination from the coordination water. The low number of hydrophilic sites of PB-2 was responsible for its insufficient Cs(+) adsorption ability.

2.
Anal Bioanal Chem ; 374(6): 1101-4, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12458427

RESUMEN

The number of water molecules in the inner-sphere (N(H2O)) was determined for Eu(III) and the strength of ligand field (R(E/M)) was evaluated for a variety of coordination environments from the luminescence lifetime and the relative intensity at 615 nm and at 592 nm, by time-resolved laser-induced fluorescence spectroscopy. When R(E/M) and deltaN(H2O) for Eu(III) with a known coordination environment were plotted clear regularity was apparent between the location of the R(E/M)-deltaN(H2O) plot and the coordination environment of Eu(III). Here, deltaN(H2O) was calculated by use of the equation, deltaN(H2O)=9-N(H2O). Unknown coordination environments of Eu(III) can, in turn, be characterized, including both the inner- and the outer-sphere, simply by plotting R(E/M) and deltaN(H2O) for Eu(III) on the diagram. This empirical method is effective for prediction of the coordination environment of hydrated and complexed Eu(III) in solutions and that of the adsorbed Eu(III) on ion-exchange resins and by microorganisms.

4.
Childs Nerv Syst ; 11(12): 712-4, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8750954

RESUMEN

We report the case of a 4-year-old boy with a postoperative hypothalamic tumor, who exhibited unusual water and electrolyte disturbance. This developed as a late manifestation during the course of central diabetes insipidus (DI), which started when the patient was 2 years old. Clinically, hyponatremia and DI appeared alternately within 1 day. The hyponatremia (lowest value Na+ 115 mmol/I) was associated with afebrile convulsions. Assessment of fluid status revealed that the patient had a reduced capacity for arginine vasopressin(AVP) secretion (partial DI), which was not physiologically regulated and which was not concomitantly sufficient to produce maximally concentrated urine and allow the production of maximally diluted urine. This defective osmoreceptor function in association with the previously existing reduced capacity for AVP release seemed to be responsible for the fluid disturbance in the patient. The administration of nasal 1-desamino-8D-arginine vasopressin (DDAVP) only when urine output was increased, instead of regular administration at a fixed time, prevented both worsening of hyponatremia and development of DI.


Asunto(s)
Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Diabetes Insípida/patología , Diabetes Insípida/cirugía , Hiponatremia/complicaciones , Hiponatremia/etiología , Complicaciones Posoperatorias , Arginina Vasopresina/uso terapéutico , Preescolar , Humanos , Hiponatremia/tratamiento farmacológico , Masculino , Concentración Osmolar
5.
Metabolism ; 44(4): 419-23, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7723663

RESUMEN

To assess the influence of gonadal steroid testosterone (T) on bone mineral status in males during puberty, we observed the response of cortical bone density and serum biochemical parameters of bone metabolism to T treatment in 12 adolescent patients with hypogonadotropic hypogonadism (11 with both gonadotropin and growth hormone deficiency and one with isolated gonadotropin deficiency). The 12 patients aged 15 to 21 years (Tanner stage I to II) were divided into two groups: group 1 (n = 6) given T treatment for 2 consecutive years, and group 2 (n = 6) without T treatment for the first year and then with T treatment for the second year. Cortical bone density measured in the radius was less than the age-matched mean value for normal subjects in all 12 patients (groups 1 and 2) at the start of the study. Bone density in group 1 increased significantly during the 2-year T treatment period, but did not increase in group 2 during the first year without T treatment, although an increase was observed during the subsequent year with T treatment. Among circulating biochemical factors such as osteocalcin, parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OHD), and 1,25-dihydroxyvitamin D [1,25-(OH)2D], only osteocalcin showed an increase in response to T treatment in both groups. Levels of insulin-like growth factor-I (IGF-I) remained consistently low and did not change in any patients except one with isolated gonadotropin deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Huesos/metabolismo , Hipogonadismo/metabolismo , Testosterona/farmacología , Adolescente , Adulto , Humanos , Masculino , Osteocalcina/sangre , Vitamina D/sangre
9.
Childs Nerv Syst ; 8(2): 81-2, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1591751

RESUMEN

We describe two children who after cardiopulmonary arrest developed hypernatremia at the terminal stage. Urinary antidiuretic hormone concentration was very low, indicating central diabetes insipidus. These cases illustrate the necessity of alertness to the development of central diabetes insipidus in patients with severe hypoxic brain damage.


Asunto(s)
Daño Encefálico Crónico/fisiopatología , Diabetes Insípida/fisiopatología , Hipoxia Encefálica/fisiopatología , Vasopresinas/deficiencia , Adolescente , Obstrucción de las Vías Aéreas/fisiopatología , Parálisis Cerebral/fisiopatología , Humanos , Lactante , Masculino , Neurohipófisis/fisiología , Resucitación , Vasopresinas/orina , Equilibrio Hidroelectrolítico/fisiología
10.
Prostaglandins Leukot Essent Fatty Acids ; 43(3): 197-201, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1871184

RESUMEN

Our previous study demonstrated that levels of dihomo-gamma-linolenic acid (DGLA) and arachidonic acid in serum total lipids decreased in association with increased plasma levels of prostaglandins E2 (PGE2) and F2 alpha (PGF2 alpha) in patients with insulin-dependent diabetes mellitus. In this study, 11 children with insulin-dependent diabetes mellitus completed a double-blind, placebo-controlled study to assess the effect of dietary supplementation with gamma-linolenic acid (GLA) on serum essential fatty acid and plasma PGE2 and PGF2 alpha levels. GLA was given as the seed oil from the evening primrose (EPO) and all patients received either EPO capsules (containing 45 mg of GLA and 360 mg of linoleic acid) or indistinguishable placebo capsules for 8 months. Initially patients took 2 capsules daily for 4 months then 4 capsules daily for a further 4 months. All patients were assessed at the start of the study, after 4 months and at the end of the study, by measuring serum essential fatty acid and plasma PGE2 and PGF2 alpha levels. After administration of 4 capsules daily the DGLA levels increased and PGE2 levels decreased significantly (p less than 0.01) in the EPO compared with the placebo group. Neither fatty acid nor PGE2 and PGF2 alpha levels were altered by administration of 2 EPO capsules daily. This suggests that the altered essential fatty acid and PG metabolism in diabetes may be reversed by direct GLA supplementation.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Ácidos Grasos Esenciales/farmacología , Ácidos Grasos/sangre , Prostaglandinas/sangre , Adolescente , Niño , Dinoprost/sangre , Dinoprostona/sangre , Método Doble Ciego , Ácidos Grasos Esenciales/administración & dosificación , Femenino , Humanos , Ácidos Linoleicos , Masculino , Oenothera biennis , Aceites de Plantas , Ácido gammalinolénico
14.
Dtsch Med Wochenschr ; 113(49): 1913-5, 1988 Dec 09.
Artículo en Alemán | MEDLINE | ID: mdl-3197614

RESUMEN

The salivary concentration of 17-hydroxyprogesterone (17-OHP) was determined in 11 patients (aged 6 months to 13 years) with congenital adrenogenital syndrome (AGS) due to C21-hydroxylase deficiency and six healthy controls, in order to assess its value in monitoring treatment of AGS. Salivary 17-OHP was measured by a specific radioimmunoassay after extraction with dichloromethane. Only 100 microliters of saliva was needed for the assay. There was a good correlation (r = 0.93; P less than 0.01) between 17-OHP concentrations in paired saliva and serum samples from the patients and the control subjects. There was a wide scatter in salivary 17-OHP levels in the range between 164 ng/l (1.7 ng/ml in serum) of satisfactorily or overtreated patients and 15,500 ng/l (247 ng/l in serum) of undertreated patients. Levels in normal children were between 200 and 300 ng/l. It is concluded that treatment of congenital AGS (21-hydroxylase deficiency) can be carefully monitored in children with the noninvasive, frequently repeatable measurement of salivary 17-OHP.


Asunto(s)
Hiperplasia Suprarrenal Congénita/tratamiento farmacológico , Hidroxiprogesteronas/análisis , Saliva/análisis , 17-alfa-Hidroxiprogesterona , Adolescente , Hiperplasia Suprarrenal Congénita/sangre , Hiperplasia Suprarrenal Congénita/diagnóstico , Niño , Preescolar , Femenino , Fludrocortisona/uso terapéutico , Humanos , Hidrocortisona/uso terapéutico , Hidroxiprogesteronas/sangre , Lactante , Masculino , Monitoreo Fisiológico , Radioinmunoensayo
15.
J Pediatr Gastroenterol Nutr ; 5(6): 878-82, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3467055

RESUMEN

To study prostaglandin (PG) metabolism in children with insulin-dependent diabetes mellitus, plasma levels of PGE2, PGF2 alpha, and thromboxane B2 and the composition of serum fatty acids were measured. Platelet aggregation, a risk factor in diabetic vascular complications, was also measured. The mean levels of plasma PGE2 and PGF2 alpha were high and serum dihomo-gamma-linolenic acid and arachidonic acid were low in the diabetic children. The plasma thromboxane B2 levels of the diabetic children and normal controls were not significantly different. Platelet aggregation was also increased in diabetic patients. These results suggest that the insulin deficiency and high blood sugar in diabetic children may disturb the supply of dihomo-gamma-linolenic acid from cis-linoleic acid, decreasing prostaglandin formation in series 1. Then feedback regulation may increase production of PGE2 and PGF2 alpha in series 2. Altered PG metabolism may be responsible for the occurrence and progression of vascular complications in the diabetic children.


Asunto(s)
Diabetes Mellitus Tipo 1/sangre , Prostaglandinas/sangre , Adolescente , Niño , Preescolar , Dinoprost , Dinoprostona , Ácidos Grasos/sangre , Femenino , Humanos , Masculino , Agregación Plaquetaria , Prostaglandinas E/sangre , Prostaglandinas F/sangre , Tromboxano B2/sangre
16.
Clin Pediatr (Phila) ; 25(11): 559-61, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3769372

RESUMEN

Two sisters who presented with a similar growth pattern are described. They delivered with idiopathic intrauterine growth retardation and had an early adolescent growth spurt. The physical and endocrine findings suggested a potential relationship between intrauterine growth retardation and early puberty.


Asunto(s)
Retardo del Crecimiento Fetal/complicaciones , Trastornos del Crecimiento/complicaciones , Adolescente , Niño , Femenino , Retardo del Crecimiento Fetal/genética , Hormonas Esteroides Gonadales/sangre , Trastornos del Crecimiento/genética , Humanos , Embarazo , Pubertad Precoz/fisiopatología , Caracteres Sexuales , Maduración Sexual
17.
Am J Dis Child ; 140(10): 998-1000, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2875648

RESUMEN

Two patients with hypothyroidism had detectable serum levels of thyrotropin binding inhibitor immunoglobulin (TBII). Patient 1 was a newborn infant who had transient neonatal hypothyroidism due to transfer of TBII from the mother with nongoitrous autoimmune thyroiditis. Patient 2 was an 8-year-old girl with Down's syndrome who presented with signs of myxedema and central precocious puberty. She had no goiter, and the recognition of thyroid disease was delayed; the histological diagnosis of chronic lymphocytic thyroiditis was established by aspiration biopsy, and TBII had strong thyroid adenyl cyclase-inhibiting activity in vitro. It appears that TBII may be pathogenetically important for occurrence of neonatal hypothyroidism and nongoitrous autoimmune thyroiditis without goiter.


Asunto(s)
Hipotiroidismo/inmunología , Inmunoglobulina G/análisis , Adenilil Ciclasas/análisis , Adulto , Enfermedades Autoinmunes/inmunología , Niño , Femenino , Humanos , Hipotiroidismo/enzimología , Hipotiroidismo/etiología , Inmunoglobulinas Estimulantes de la Tiroides , Recién Nacido , Intercambio Materno-Fetal , Embarazo , Complicaciones del Embarazo/inmunología , Tiroiditis Autoinmune/inmunología
18.
Acta Paediatr Scand ; 75(5): 875-8, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3564956

RESUMEN

A 5-month-old boy with giant cell hepatitis died of hepatic failure. Analysis of serum bile acids by high pressure liquid chromatography revealed a marked increase in total bile acid concentration and a decrease in the cholate to chenodeoxycholate ratio. However, contrary to expectation, the conjugating ability of bile acids with taurine or glycine was well preserved. This suggests that the amino acid conjugation can occur despite the presence of severe hepatocellular damage.


Asunto(s)
Ácidos y Sales Biliares/sangre , Ictericia Neonatal/sangre , Cromatografía Líquida de Alta Presión , Hepatitis/sangre , Humanos , Lactante , Ictericia Neonatal/complicaciones , Hígado/patología , Masculino
19.
Clin Pediatr (Phila) ; 24(6): 347-50, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3995865

RESUMEN

A 13-year-old girl presenting with abdominal pain, polyuria, polydipsia, and radiologically confirmed renal calculi was diagnosed as having primary hyperparathyroidism. Laboratory data revealed markedly elevated serum calcium, low phosphorus, and elevated parathyroid hormone. Other parathyroid function tests also confirmed the diagnosis of primary hyperparathyroidism. Ultrasound examination showed a small echogenic nodule in the parathyroid gland. Following a single gland resection, the extremely high serum calcium level promptly decreased to normal range, and it has remained normal.


Asunto(s)
Hiperparatiroidismo , Adolescente , Calcio/sangre , Femenino , Estudios de Seguimiento , Humanos , Hipercalcemia/etiología , Hiperparatiroidismo/diagnóstico , Hiperparatiroidismo/patología , Hiperparatiroidismo/cirugía , Glándulas Paratiroides/patología , Glándulas Paratiroides/cirugía , Fósforo/sangre
20.
Eur J Pediatr ; 143(4): 308-10, 1985 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3987732

RESUMEN

The case of a 14-month-old girl presenting with precocious breast development due to adrenal hyperplasia is reported. The endocrine studies revealed a slight elevation of the plasma progesterone, 17 alpha-hydroxyprogesterone, testosterone and oestrone levels, and an increased urinary oestrogen excretion. The findings of the ultrasound examination and the evidence that the oestradiol concentration in the left adrenal vein was higher than in the right adrenal vein confirmed the diagnosis of left adrenal hyperfunction. Surgical exploration revealed unilateral hyperplasia of the adrenal cortex. After adrenalectomy the plasma hormone levels and urinary oestrogen excretion fell to normal, with concomitant regression of breast tissue. The girl shows no signs of recurrence of the disorder in a 2 year follow-up. This adrenal hyperplasia might be a benign adrenal disorder causing precocious breast development.


Asunto(s)
Hiperplasia Suprarrenal Congénita/complicaciones , Mama/crecimiento & desarrollo , 17-alfa-Hidroxiprogesterona , Corteza Suprarrenal/patología , Hiperplasia Suprarrenal Congénita/metabolismo , Hiperplasia Suprarrenal Congénita/patología , Estrógenos/metabolismo , Femenino , Humanos , Hidroxiprogesteronas/metabolismo , Lactante , Progesterona/metabolismo , Testosterona/metabolismo
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