Browsing by Author "Gonzalez, G"
Now showing 1 - 6 of 6
Results Per Page
Sort Options
- ItemAssociation of primary antiphospholipid syndrome with primary adrenal insufficiency(J RHEUMATOL PUBL CO, 1996) Gonzalez, G; Gutierrez, M; Ortiz, M; Tellez, R; Figueroa, F; Jacobelli, SThe association of primary adrenal insufficiency with antiphospholipid antibodies is usually reported in the context of adrenal thrombosis or hemorrhage. We describe a 35-year-old woman who developed a primary antiphospholipid syndrome (spontaneous abortion, thrombocytopenia, and cerebrovascular occlusion) in association with primary adrenal insufficiency without evidence of suprarenal hemorrhage or thrombosis.
- ItemBone turnover and density in healthy women during breastfeeding and after meaning(1996) Lopez, JM; Gonzalez, G; Reyes, V; Campino, C; Diaz, STo investigate the changes in maternal bone density and turnover associated with lactation we ran a longitudinal study in fully breastfeeding women (age 26.3+/-4.1 years, mean+/-SD) at the first (stage I, n = 30) and sixth (stage II, n = 25) months postpartum and 6 months after weaning (stage III, n = 20), and in a contemporary control group of non-nursing women. At each time point bone density, serum calcium, phosphorus, alkaline phosphatases, parathyroid hormone (PTH), osteocalcin, follicle stimulating hormone (FSH), estradiol (E(2)), prolactin (PRL) urinary hydroxyproline and creatinine (OH-P/Cr) were measured in both groups. The daily calcium intake of nursing women (1479 +/- 590 mg/day at stage I) was higher than in non-nursing women (536 +/- 231 mg/day at stage I). Biochemical markers of bone turnover were higher (p<0.05) in nursing than in non-nursing women at stages I and II, while in stage III only OH-P/Cr was elevated. The lumbar spine (L2-4) bone mineral density was similar in the two groups at the beginning of the study (1.148 +/- 0.111 g/cm(2) in nursing women vs 1.211 +/- 0.102 g/cm(2) in non-nursing women; p = 0.56), but it was lower in nursing women at stage II (1.144 +/- 0.110 g/cm(2) vs 1.216 +/- 0.095 g/cm(2) respectively; p<0.05). Right cm femoral neck bone density decreased by 3% between stages I and II in nursing women but did not differ from values in non-nursing women (0.947 +/- 0.110 vs 0.973 +/- 0.108 in stage I and 0.918 +/- 0.114 vs 0.975 +/- 0.098 in stage II respectively; p<0.05, ANOVA). After weaning, lumbar spine and femoral neck bone density increased by 6% and 8% respectively (p<0.05, ANOVA). No correlation was found between changes in bone turnover markers or bone density and parity, frequency and duration of nursing episodes, body weight, body mass index, and plasma PRL, E(2) and PTH levels. We conclude that in nursing women with a daily calcium intake at the recommended dietary allowance (>1200 mg/day), full breastfeeding extending over 6 months is characterized by increased maternal bone turnover and a transient bone loss which normalizes after weaning.
- ItemDoes perchlorate in drinking water affect thyroid function in newborns or school-age children?(2000) Crump, C; Michaud, P; Tellez, R; Reyes, C; Gonzalez, G; Montgomery, EL; Crump, KS; Lobo, G; Becerra, C; Gibbs, JPPerchlorate is known to suppress thyroid function by inhibiting uptake of iodide by the human thyroid at doses of 200 mg/day or greater. A study was conducted to investigate the potential effects of perchlorate in drinking water on thyroid function in newborns and school-age children. A total of 162 school-age children and 9784 newborns were studied in three proximate cities in northern Chile that have different concentrations of perchlorate in drinking water: Taltal (100 to 120 mu g/L), Chanaral (5 to 7 mu g/L), and Antofagasta (non-detectable: <4 mu g/L). Among schoolchildren, no difference was found in thyroid-stimulating hormone levels or goiter prevalence among lifelong residents of Taltal or Chanaral compared with those of Antofagasta, after adjusting for age, sex, and urinary iodine. No presumptive cases of congenital hypothyroidism were detected in Taltal or Chanaral; seven cases were detected in Antofagasta. Neonatal thyroid-stimulating hormone levels were significantly lower in Taltal compared with Antofagasta; this is opposite to the known pharmacological effect of perchlorate, and the magnitude of difference did not seem to be clinically significant. These findings do not support the hypothesis that perchlorate in drinking water at concentrations as high as 100 to 120 mu g/L suppresses thyroid function in newborns or school-age children.
- ItemDynamic modelling and advanced multivariable control of conventional flotation circuits(PERGAMON-ELSEVIER SCIENCE LTD, 1998) Perez Correa, R; Gonzalez, G; Casali, A; Cipriano, A; Barrera, R; Zavala, EExpert and predictive multivariable control algorithms for a conventional cooper flotation circuit were assessed through simulations These simulations were carried out with a nonlinear dynamic model, derived from mass balances and empirical relationships, that qualitatively reproduced the dynamic behaviour of a real plant well. In order to make the simulations more realistic, they included noisy measurements, stochastic parameter variations and input disturbances. New expert algorithms were able to keep the plant operating within a pre-defined zone for long periods without complete control saturation, unlike previous expert controllers. In addition, the inclusion of constraints in a multivariable predictive algorithm verified improved control system regulation and flexibility. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.
- ItemPathological characteristics of thyroid microcarcinoma. A review of 402 biopsies(2005) Fardella, C; Jimenez, M; Gonzalez, H; Leon, A; Goni, I; Cruz, F; Solar, A; Torres, J; Mosso, L; Gonzalez, G; Rodriguez, JA; Campusano, C; Lopez, JM; Arteaga, EBackground: Thyroid microcarcinoma is a tumor of 10 mm or less. that should have a low risk of mortality. However a subgroup of these carcinomas is as aggressive as bigger tumors. Aim To describe the pathological presentation of these tumors.. and compare them with larger tumors. Material and methods. All Pathological samples of thyroid carcinoma that were obtained between 1992 and 2003, were studied. In all biopsies, the pathological type, tumor size. the focal or multifocal character the presence of lymph node involvement and the presence of lymphocytic thyroiditis or thyroid hyperplasia, were recorded. Results: One hundred eighteen microcarcinomas and 284 larger tumors were studied. The mean age of patients with microcarcinoma and larger tumors was 42.7 +/- 14 and 49.3 +/- 16 years respectively (p < 0,00.1) and 83% were female. without gender differences between tumor types. klean size of microcarcinomas was 8.6 mm and 116 (98%) were papillary carcinomas. Of these. 109 (94% were well differentiated and seven (6%) were moderatly differentiated. Thirty six(31%) were multifocal and in 10 (8,6%), there was lymph node involvement. The mean size of larger tumors was 23.8 mm and 241 (85%) were papillary carcinomas. Of these, 200 (83%) were well differentiated, and 41 (17%) were moderately differentiated.Eighty five (35%) were multifocal and in 44 (18%) there was lymph node involvement. The prevalence of thyroiditis and hyperplasia was significantly higher among microcardinomas than in larger tumors (15 and 2.5%, respectively, p < 0.001, for the former; 32.4 and 1.7%, respectively, p < 0.001, for the latter. Conclusions. In this series. one third of microcarcinomas were multifocal and 10% had lymph node involvement. Therefore, aggresiveness of these tumors is higher than what is reported in the literature and they should be treated with total thyroidectomy.
- ItemSuccessful treatment of hyperthyroidism with amiodarone in a patient with propylthiouracil-induced acute hepatic failure(MARY ANN LIEBERT, INC, 2004) Brusco, F; Gonzalez, G; Soto, N; Arteaga, EAcute hepatic failure is a rare and potentially lethal complication of propylthiouracil (PTU) use for hyperthyroidism. We present a 20-year-old woman with Basedow-Graves' disease who developed PTU-induced fulminant hepatitis, which progressed to acute hepatic failure with grade III hepatic encephalopathy. Laboratory evaluation ruled out the most common causes of fulminant hepatitis. We treated her hyperthyroidism with amiodarone (average daily dose, 200 mg) for 3 weeks, achieving rapid and persistent euthyroidism, (triiodothyronine [T-3] levels ranged between 64 and 109 ng/dL) without side effects. Amiodarone treatment did not abolish the thyroid radioactive iodine uptake (RAIU), allowing for subsequent treatment with radioactive iodine. The clinical course was favorable and the patient achieved full hepatic recovery 3 months after the hepatic failure was detected. After an extensive review of the literature, we believe that this is the first communication of the successful use of amiodarone to control hyperthyroidism in a patient with PTU-induced fulminant hepatitis.