Assuntos

Aldosterona/sangue , Hiperaldosteronismo/sangue , Complicações na Gravidez/sangue , Progesterona/sangue , Adolescente , Feminino , Humanos , Gravidez , Adulto Jovem

RESUMO

OBJECTIVE: High sodium (HS) diet is associated with hypertension (HT) and insulin resistance (IR). We evaluated whether HS diet was associated with a dysregulation of cortisol production and metabolic syndrome (MetS). PATIENTS AND MEASUREMENTS: We recruited 370 adults (18-85 years, BMI 29·3 ± 4·4 kg/m(2) , 70% women, 72% HT, 61% MetS). HS diet (urinary sodium >150 mEq/day) was observed in 70% of subjects. We measured plasma hormones, lipid profile, urinary free cortisol (UFC) and cortisol tetrahydrometabolites (THM). RESULTS: Urinary sodium was correlated with UFC (r = +0·45, P < 0·001), cortisol THM (r = +0·41, P < 0·001) and inversely with adiponectin, HDL and aldosterone, after adjusting by age, gender and BMI. Subjects with high, compared with adequate sodium intake (50-149 mEq/day) had higher UFC (P < 0·001), THM (P < 0·001), HOMA-IR (P = 0·04), HT (81% vs 50%, P < 0·001), MetS (69% vs 41%, P < 0·001) and lower adiponectin (P = 0·003). A multivariate predictive model adjusted by confounders showed a high discriminative capacity for MetS (ROC curve 0·878) using four clinical variables: HS intake [OR = 5·6 (CI 2·3-15·3)], HOMA-IR [OR 1·7 (1·3-2·2)] cortisol THM [OR 1·2 (1·1-1·4)] and adiponectin [OR = 0·9 (0·8-0·9)], the latter had a protective effect. CONCLUSIONS: High sodium diet was associated with increased urinary cortisol and its metabolites. Also, HS diet was associated with HT, insulin resistance, dyslipidaemia and hypoadiponectinaemia, even when adjusting by confounding variables. Further, we observed that high salt intake, IR and higher cortisol metabolites, alone or combined in a clinical simple model, accurately predicted MetS status, suggesting an additive mechanism in obesity-related metabolic disorders.

Assuntos

Hidrocortisona/urina , Resistência à Insulina , Síndrome Metabólica/epidemiologia , Sódio na Dieta/efeitos adversos , Adiponectina/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Aldosterona/urina , Glicemia/análise , Índice de Massa Corporal , Estudos de Coortes , Feminino , Glucocorticoides/metabolismo , Glucocorticoides/urina , Humanos , Hidrocortisona/metabolismo , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Razão de Chances , Sódio na Dieta/urina , Adulto Jovem

RESUMO

Hypertension is traditionally considered a disease in which elevated blood pressure contributes to inflammation and activation of the immune system, leading to cardiovascular injury and end-organ damage. Here, we discuss the effects of aldosterone on the immune system and aldosterone's contribution to vascular pathogenesis. Studies in human have suggested a broader role for aldosterone, beyond elevating blood pressure. Recent clinical data support the notion that aldosterone can directly alter the function of the immune system and cause vascular-damaging inflammation. Clinical observations have been reproduced in experimental models of hypertension, further supporting the idea that an aberrant immune response contributes to the onset of hypertension. Such studies have shown that myeloid cells are required to induce the disease and IL-17-producing CD4(+) T cells may contribute to maintaining aldosterone-mediated hypertension. In addition, regulatory T cells diminish the inflammatory damage caused by aldosterone during hypertension. This is a very active area of research that could lead to new therapeutic targets for treating hypertension.

Assuntos

Aldosterona/farmacologia , Vasos Sanguíneos/patologia , Genoma Humano/genética , Hipertensão/imunologia , Hipertensão/patologia , Sistema Imunitário/patologia , Vasos Sanguíneos/efeitos dos fármacos , Humanos , Estresse Oxidativo/efeitos dos fármacos

RESUMO

In nonhuman primates and rodents, melatonin acting directly on the adrenal gland, inhibits glucocorticoid response to ACTH. In these species, an intrinsic adrenal circadian clock is involved in ACTH-stimulated glucocorticoid production. We investigated whether these findings apply to the human adrenal gland by determining i) expression of clock genes in vivo and ii) direct effects of melatonin in ACTH-stimulated adrenal explants over a) expression of the clock genes PER1 (Period 1) mRNA and BMAL1 [Brain-Muscle (ARNT)-like] protein, ACTH-induced steroidogenic acute regulatory protein (StAR), and 3ß-hydroxysteroid dehydrogenase (3ß-HSD) and b) over cortisol and progesterone production. Adrenal tissue was obtained from 6 renal cancer patients undergoing unilateral nephrectomy-adrenalectomy. Expression of the clock genes PER1, PER2, CRY2 (Cryptochrome 2), CLOCK (Circadian Locomotor Output Cycles Kaput) and BMAL1, was investigated by RT-PCR in a normal adrenal and in an adenoma. In independent experiments, explants from 4 normal adrenals were preincubated in culture medium (6 h) followed by 12 h in: medium alone; ACTH (100 nM); ACTH plus melatonin (100 nM); and melatonin alone. The explants' content of PER1 mRNA (real-time PCR) and StAR, 3ß-HSD, BMAL1 (immuno slot-blot), and their cortisol and progesterone production (RIA) were measured. The human adrenal gland expresses the clock genes PER1, PER2, CRY2, CLOCK, and BMAL1. ACTH increased PER1 mRNA, BMAL1, StAR, and 3ß-HSD protein levels, and cortisol and progesterone production. Melatonin inhibited these ACTH effects. Our study demonstrates, for the first time, direct inhibitory effects of melatonin upon several ACTH responses in the human adrenal gland.

Assuntos

Glândulas Suprarrenais/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Regulação para Baixo , Melatonina/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Idoso , Feminino , Expressão Gênica , Humanos , Hidrocortisona/metabolismo , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Progesterona/metabolismo

RESUMO

The circadian production of glucocorticoids involves the concerted action of several factors that eventually allow an adequate adaptation to the environment. Circadian rhythms are controlled by the circadian timing system that comprises peripheral oscillators and a central rhythm generator located in the suprachiasmatic nucleus (SCN) of the hypothalamus, driven by the self-regulatory interaction of a set of proteins encoded by genes named clock genes. Here we describe the phase relationship between the SCN and adrenal gland for the expression of selected core clock transcripts (Per-2, Bmal-1) in the adult capuchin monkey, a New World, diurnal nonhuman primate. In the SCN we found a higher expression of Bmal-1 during the h of darkness (2000-0200 h) and Per-2 during daytime h (1400 h). The adrenal gland expressed clock genes in oscillatory fashion, with higher values for Bmal-1 during the day (1400-2000 h), whereas Per-2 was higher at nighttime (about 0200 h), resulting in a 9- to 12-h antiphase pattern. In the adrenal gland, the oscillation of clock genes was accompanied by rhythmic expression of a functional output, the steroidogenic enzyme 3beta-hydroxysteroid dehydrogenase. Furthermore, we show that adrenal explants maintained oscillatory expression of Per-2 and Bmal-1 for at least 36 h in culture. The acrophase of both transcripts, but not its overall expression along the incubation, was blunted by 100 nm melatonin. Altogether, these results demonstrate oscillation of clock genes in the SCN and adrenal gland of a diurnal primate and support an oscillation of clock genes in the adrenal gland that may be modulated by the neurohormone melatonin.

Assuntos

Glândulas Suprarrenais/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Ritmo Circadiano/fisiologia , Flavoproteínas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Melatonina/farmacologia , Melatonina/fisiologia , Núcleo Supraquiasmático/metabolismo , 3-Hidroxiesteroide Desidrogenases/genética , Fatores de Transcrição ARNTL , Animais , Cebus , Criptocromos , RNA Mensageiro/análise , RNA Ribossômico 18S/análise

RESUMO

UNLABELLED: Multiple endocrine neoplasia type 1 (MEN1) is a syndrome inherited in an autosomal dominant trait caused by the inactivation of the tumor suppressor gene MEN1. OBJECTIVE: To communicate a family with a new heterozygous germ line mutation in the intronic region of MEN1 gene and to study its influence in the menin expression. PATIENTS AND METHODS: We studied 5 members of a family with symptomatic hyperparathyroidism (HPT). One of them had also a neuroendocrine pancreatic tumor, and 2 had non-functional multinodular cortical adrenal hyperplasia compatible with the diagnosis of MEN1. After the mutation was identified, HSP92II restriction enzyme was used to determine both zygosity and segregation of the mutation. RT-PCR from leukocyte's isolated mRNA and western blot from pancreatic tumor tissue were performed. In vitro studies were done in Chinese hamster ovary (CHO) cells transfected with reporter minigenes carrying the coding regions spanning exon (EX)-intron 9 and EX10 with the mutant and the wild type sequences. RESULTS: We identified a heterozygous G-to-T substitution in the intron-EX junction (IVS9-1 G>T) of MEN1 gene in the index case and the family members. The mRNA from patient's leukocytes was larger (934 bp) in comparison to the normal transcript (717 bp). Immunoblot analysis demonstrated that wild type (67 kDa) and two additional mutant proteins (approximately 55 and approximately 90 kDa) were expressed in the pancreatic tissue. The in vitro study showed a 45% nuclear localization of the mutated menin signal and a 95% in the wild type protein. CONCLUSIONS: We identified a new intronic heterozygous germ line mutation (IVS9-1G>T) of MEN1 gene in a family affected by MEN1 syndrome. This mutation alters the splice acceptor site of intron 9 that promotes an incorrect splicing, generating aberrant proteins without the nuclear localization signals necessary for the normal menin translocation to the nucleus.

Assuntos

Núcleo Celular/metabolismo , Mutação em Linhagem Germinativa/genética , Neoplasia Endócrina Múltipla Tipo 1/genética , Proteínas Proto-Oncogênicas/metabolismo , Adulto , Idoso de 80 Anos ou mais , Processamento Alternativo , Criança , Chile , DNA/genética , Feminino , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico , Linhagem , Análise de Sequência de DNA

RESUMO

In the adult mammal the circadian system, which allows predictive adaptation to daily environmental changes, comprises peripheral oscillators in most tissues, commanded by the suprachiasmatic nucleus (SCN) of the hypothalamus. The external environment of the fetus is provided by its mother. In primates, maternal melatonin is a candidate to entrain fetal circadian rhythms, including the SCN rhythms of metabolic activity. We found in the 90% of gestation capuchin monkey fetus expression of the clock genes Bmal-1, Per-2, Cry-2, and Clock in the SCN, adrenal, pituitary, brown fat, and pineal. Bmal-1, Per-2, and the melatonin 1 receptor (MT1) showed a robust oscillatory expression in SCN and adrenal gland, whereas a circadian rhythm of dehydroepiandrosterone sulphate was found in plasma. Maternal melatonin suppression changed the expression of Bmal-1, Per-2, and MT1 in the fetal SCN. These effects were reversed by maternal melatonin replacement. In contrast, neither maternal melatonin suppression nor its replacement had effects on the expression of Per-2 and Bmal-1 or MT1 in the fetal adrenal gland or the circadian rhythm of fetal plasma dehydroepiandrosterone sulphate. Our data suggest that maternal melatonin is a Zeitgeber for the fetal SCN but probably not for the adrenal gland.

Assuntos

Feto/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Melatonina/fisiologia , Transativadores/genética , Fatores de Transcrição ARNTL , Glândulas Suprarrenais/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas CLOCK , Cebus , Ritmo Circadiano/genética , Ritmo Circadiano/fisiologia , DNA Complementar/biossíntese , DNA Complementar/genética , Sulfato de Desidroepiandrosterona/sangue , Feminino , Hidrocortisona/sangue , Proteínas Nucleares/genética , Gravidez , Receptor MT1 de Melatonina/biossíntese , Receptor MT1 de Melatonina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Núcleo Supraquiasmático/fisiologia , Temperatura , Fatores de Transcrição/genética

RESUMO

Thyroid hormone resistance is a rare autosomal dominant disease associated, in more than 90% of cases, to mutations in the beta thyroid hormone receptor. We report a 23 years old male that consulted for a psychiatric condition. Clinically, the patient was euthyroid in spite of high total and free T4 and T3 concentrations, while TSH remained normal. Also, TSH showed a five fold increase under TRH stimulation. The mother and one of his brothers had the same pattern of abnormal serum thyroid hormones. We discuss the diagnostic considerations and the protocol to study this rare pathology.

Assuntos

Adulto , Humanos , Masculino , Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/genética , Síndrome da Resistência aos Hormônios Tireóideos/diagnóstico , Glândula Tireoide/patologia , Glândula Tireoide , Hormônios Tireóideos/sangue , Saúde da Família , Síndrome da Resistência aos Hormônios Tireóideos/genética

RESUMO

BACKGROUND: Fully breastfeeding women experience an amenorrhoea of variable duration. Our aim was to identify in pregnancy, endocrine markers that could predict the duration of subsequent lactational amenorrhoea. METHODS: We studied 17 healthy women at 34 and 38 weeks gestation, and 1 and 3 months post-partum. The women fully breastfed until 6 months post-partum. During pregnancy, prolactin (PRL), oestrogens (total oestradiol, unconjugated oestrone, unconjugated oestriol), sex hormone binding globulin (SHBG), dehydroepiandrosterone sulphate (DHEA-S), progesterone and placental lactogen, and during post-partum PRL, oestrogens and SHBG, were measured. Free oestradiol in pregnancy and post-partum was calculated. RESULTS: Ten women experienced long (>6 months) and seven experienced short (<6 months) lactational amenorrhoea. At 38 weeks gestation, the women who experienced a long lactational amenorrhoea had twice as much PRL, about half the total oestradiol, lower SHBG concentration (P < 0.05, Student's t-test, Bonferroni modification) and similar free oestradiol concentration, compared with those who experienced short lactational amenorrhoea. The difference in PRL concentration persisted in post-partum postsuckling samples. CONCLUSION: At 38 weeks gestation, the ratio PRL/oestradiol identified all individual women according to the subsequent duration of their lactational amenorrhoea, suggesting that duration of lactational amenorrhoea is conditioned during pregnancy.

Assuntos

Amenorreia , Estradiol/sangue , Idade Gestacional , Período Pós-Parto , Prolactina/sangue , Adulto , Sulfato de Desidroepiandrosterona/sangue , Estriol/sangue , Estrona/sangue , Feminino , Humanos , Lactogênio Placentário/sangue , Gravidez , Progesterona/sangue , Globulina de Ligação a Hormônio Sexual/análise , Fatores de Tempo

RESUMO

BACKGROUND: Calcitonin is specially indicated for the treatment of osteoporosis in women that cannot receive estrogen replacement therapy or that have a high bone turnover rate. AIM: To study the effects of low intranasal calcitonin doses on bone remodeling in postmenopausal women with a high bone turnover. PATIENTS AND METHODS: Forty one healthy women aged 56 +/- 6 years old, with a mean lapse after menopause of 7.6 +/- 6.5 years and with a high bone turnover rate, evidenced by an urinary hydroxyproline (mg/dl)/creatinine (g/dl) ratio of 52.4 +/- 7.2, were studied. They were randomly assigned to receive 100 or 50 U/calcitonin thrice a week during 3 months or to a control group that received placebo. All received 500 mg/day calcium carbonate. Urinary hydroxyproline/creatinine ratio was measured a 0, 15, 30, 60 and 90 days. Plasma bone fraction of alkanine phosphatases was measured at 0, 30 and 90 days. RESULTS: Initial urinary hydroxyproline/creatinine ratio and plasma bone fraction of alkanine phosphatases were similar in all study groups and there was no change in these parameters during the study period. CONCLUSIONS: Intranasal calcitonin in doses of 100 U thrice a week or less, does not modify accelerated bone turnover in postmenopausal women.

Assuntos

Remodelação Óssea/efeitos dos fármacos , Calcitonina/administração & dosagem , Osteoporose Pós-Menopausa/tratamento farmacológico , Fosfatase Alcalina/sangue , Análise de Variância , Calcitonina/uso terapêutico , Creatinina/urina , Método Duplo-Cego , Feminino , Humanos , Hidroxiprolina/urina , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/urina , Estudos Prospectivos , Fatores de Tempo

RESUMO

BACKGROUND: Thyroglobulin measurement is useful for the follow up of patients subjected to total thyroidectomy for differentiated thyroid carcinoma. Thyroglobulin autoantibodies may interfere with its determination. AIM: To measure thyroglobulin autoantibodies and their interference with thyroglobulin determination. MATERIAL AND METHODS: The presence of thyroglobulin autoantibodies was investigated in 801 serum samples sent to the laboratory for measurement of thyroglobulin levels. A serum was considered positive for these autoantibodies when radioactivity corresponding to 125I-thyroglobulin bound to thyroglobulin autoantibodies, precipitated with human gamma globulin, exceeded in 1.4 times that of a negative sera pool. In positive sera, thyroglobulin autoantibody concentration was measured and its interference with thyroglobulin radioimmunoassay was assessed through a recuperation test using exogenous thyroglobulin. RESULTS: Thyroglobulin autoantibodies were detected in 149 sera (18.6%). Of these, 65 had a recuperation that fluctuated between 1 and 80%. Thyroglobulin autoantibody concentration was negatively correlated with recuperation percentages (r = -0.64; p < 0.001) but not with thyroglobulin concentrations (r = 0.08). Thyroglobulin was higher in positive sera with a recuperation over 80% than in sera with a recuperation of less than 80% (12.7 +/- 1.7 and 5.9 +/- 0.6 ng/ml, respectively; p < 0.001). CONCLUSIONS: Thyroglobulin autoantibodies interfere with thyroglobulin measurement by radioimmunoassay, sequestering variable amounts of thyroglobulin. The presence of these autoantibodies must be investigated prior to thyroglobulin determination.

Assuntos

Autoanticorpos/análise , Tireoglobulina/sangue , Tireoglobulina/imunologia , Humanos , Reprodutibilidade dos Testes

RESUMO

Bone density and turnover was assessed in a longitudinal study of healthy lactating women who initiated use of Norplant((R)) implants (NOR, n = 29), progesterone vaginal rings (PVR, n = 28) or Copper T 380A intrauterine devices (T-Cu, n = 51, control group) around day 60 postpartum. Bone density, serum calcium, phosphorus, alkaline phosphatases, parathyroid hormone (PTH), follicle stimulating hormone (FSH), oestradiol and prolactin, and urinary hydroxyproline and creatinine were measured at postpartum months 1 (PM1), and 12 (PM12) and 6 or 12 months after weaning; at month 6 postpartum (PM6) serum and urine tests alone were performed. Baseline characteristics and lactation performance were similar between groups. Biochemical markers of bone turnover were higher at PM1, PM6 and PM12 than after weaning, with no differences between groups. Bone density in the lumbar spine (L2-L4) and femoral neck at PM1 and PM12 ( approximately 1.11 g/cm(2)) was similar in three groups. Lumbar spine values were found to be lower in lactating women than those present in non-lactating women, but increased after weaning to similar values. The two progestin-only contraceptives studied appear to have no deleterious effect upon bone density and metabolism in healthy lactating women.

Assuntos

Densidade Óssea/efeitos dos fármacos , Remodelação Óssea/efeitos dos fármacos , Anticoncepção/métodos , Anticoncepcionais Femininos/uso terapêutico , Lactação/efeitos dos fármacos , Levanogestrel/uso terapêutico , Progesterona/uso terapêutico , Administração Intravaginal , Adolescente , Adulto , Implantes de Medicamento , Feminino , Humanos , Dispositivos Intrauterinos de Cobre , Desmame

RESUMO

The association of hyperthyroxinemia and euthyroidism is frequent and characterized by high plasma thyroxin concentrations, normal TSH values and absence of clinical signs of hyperthyroidism. We report an asymptomatic 28 years old male presenting with a serum total plasma thyroxin of 18.5 micrograms/dl (N 6.1-12.5), a free thyroxin of 2.9 ng/dl (N 0.8-1.4), a TSH of 3.4 microIU/ml (N 0.5-5), and a triiodothyronine of 128 ng/dl (N 80-180). Laboratory assessment did not find high thyroxin binding globulin, albumin or prealbumin concentrations or antithyroxin antibodies. The thyroxin binding capacity of albumin was elevated to 58.2 micrograms/dl (N 11.5-34.1). TSH responded normally to TRH stimulus and was suppressed with exogenous triiodothyronine, which caused an hyperthyroid syndrome. We concluded that this patient had a familial dysalbuminemia.

Assuntos

Síndromes do Eutireóideo Doente/complicações , Hipertireoxinemia/complicações , Adulto , Síndromes do Eutireóideo Doente/sangue , Síndromes do Eutireóideo Doente/diagnóstico , Humanos , Hipertireoxinemia/sangue , Hipertireoxinemia/diagnóstico , Masculino , Albumina Sérica/análise , Tireotropina/sangue , Proteínas de Ligação a Tiroxina/análise , Tri-Iodotironina/sangue

RESUMO

To assess whether plasma prolactin (PRL) characteristics relate to lactogenesis and absence or presence of menstrual cycles, we measured bioactive PRL (BIO-PRL) using the Nb2 assay, immunoreactive PRL (IR-PRL) by radio-immunoassay, calculated equations describing the BIO-PRL-IR-PRL relationship and separated charged PRL isoforms (by chromatofocusing) in five amenorrhoeic and five cycling nursing women at 6 months postpartum and in 10 cycling non-nursing women. Plasma samples were drawn before and 30 min after a suckling episode at 0800, 1600 and 2400 h in nursing women and at the same hours in non-nursing women. BIO-PRL and IR-PRL concentrations were highest in amenorrhoeic nursing women, intermediate in cycling nursing women and lowest in cycling non-nursing women. The BIO-PRL-IR-PRL relationship shows that a given amount of IR-PRL corresponds to equivalent amounts of BIO-PRL in cycling nursing and cycling non-nursing women, and to a larger extent in amenorrhoeic nursing women. IR-PRL was present in plasma as several charge isoforms. Bioactive isoforms eluting at pH 6.0-5.1 were found in amenorrhoeic and cycling nursing women, reaching similar concentrations after suckling. Bioactive isoforms eluting at pH 7.0-6.1 were found only in amenorrhoeic nursing women. We speculate that isoforms eluting at pH 6.0-5.1 may play a role in lactation and isoforms eluting at pH 7.0-6.1, in lactational amenorrhoea.

Assuntos

Lactação/fisiologia , Prolactina/fisiologia , Adulto , Aleitamento Materno , Feminino , Humanos , Ciclo Menstrual/fisiologia , Isoformas de Proteínas/fisiologia

RESUMO

BACKGROUND: Prescription of calcium supplements is a frequent practice, considering that diet is insufficient to cover daily requirements of this mineral. AIM: To study the dissolution velocity in an acid solution, of different commercial calcium supplements. MATERIAL AND METHODS: Hydrochloric acid was added to distilled water in increasing amounts to obtain a final pH of 6.9, 3.0, 2.5, 2.0 and 1.5. Eighteen commercial calcium preparations were incubated in these solutions for 60 min and dissolution velocity was measured as the percentage of elemental calcium found in solution after this incubation period. RESULTS: Calcium carbonate preparations had a pH dependent dissolution velocity, ranging from 0.67 +/- 0.8% at pH 6.9 to 77.15 +/- 17.5% at pH 1.5. Using the solution with pH 1.5, the dissolution velocity of different preparations varied widely from 56 to 100%. Calcium acetate, followed by calcium citrate and dicalcic phosphate were the salts in tablets with better dissolution velocities. Among powders and effervescent preparations, those containing calcium lactogluconate and citrate had the better dissolution velocities (95 to 115%), that were independent of the solution's pH. A studied preparation with integral bone had a very low dissolution velocity, not surpassing 33 mg of calcium per tablet. CONCLUSIONS: The dissolution velocity of different calcium carbonate preparations varies greatly and, in conditions of achlorhydria, it is negligible. Calcium lactogluconate and citrate dissolution velocities are independent of the solution's pH.

Assuntos

Cálcio/metabolismo , Suplementos Nutricionais , Solubilidade , Cálcio/uso terapêutico , Carbonato de Cálcio/metabolismo , Citrato de Cálcio/metabolismo , Cálcio da Dieta/metabolismo , Fatores de Tempo

RESUMO

During the last two decades, the clinical presentation of primary hyperparathyroidism (PHP) has changed due to the routine use of multiphasic biochemical screening tests. We assessed 84 patients with PHP treated in our service between 1977 and 1991. The yearly incidence increased from 1.6 to 7.6 patients/year with the introduction of multiphasic biochemical testing in our hospital in 1982; likewise the proportion of asymptomatic patients increased from 12.5 to 40.7%. The most frequent presenting symptoms were bone pain and renal colic. Nineteen percent of patients were over 70 years old and this age group had distinct clinical features. The plasma chlorine/phosphorus ratio was abnormal in 95% of cases; on the contrary only 7 of 18 patients had a urinary calcium excretion over 300 mg/day. Cervical ultrasound, performed in 45 patients had a positive predictive value of 78% to localize the lesion. Bone density was below fracture threshold in 50% of studied patients. The principal surgical finding was the presence of adenoma. Twenty one percent of patients had symptomatic hypocalcemia during the first week after surgery; however, only 2.5% of patients continued to have hypocalcemia one month after surgery. One patient had an inferior laryngeal nerve damage and two a cervical hematoma. It is concluded that the introduction of massive calcium measurements has allowed an early diagnosis of asymptomatic PHP, specially in elderly people.

Assuntos

Hiperparatireoidismo/diagnóstico , Adenoma/complicações , Adenoma/diagnóstico , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Cálcio/sangue , Carcinoma/complicações , Carcinoma/diagnóstico , Feminino , Humanos , Hiperparatireoidismo/sangue , Hiperparatireoidismo/complicações , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores Sexuais , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/diagnóstico

RESUMO

The defect of 3 beta hydroxysteroid dehydrogenase (3 beta HSD) is frequent among hirsute women and clearly dependent on the ethnic composition of the studied population. Our aim was to study the frequency of 3 beta HSD deficit in a group of Chilean hirsute women. Basal and post ACTH concentrations of cortisol, 17 hydroxyprogesterone and 17 hydroxypregnenolone were measured by RIA in 40 hirsute post puberal women and in 15 normal age matched female volunteers. Criteria for considering a 3 beta HDS deficit were 17 hydroxypregnenolone values and 17 hydroxypregnenolone/17 hydroxyprogesterone and 17 hydroxypregnenolone/cortisol ratios after ACTH stimulation over the 95% confidence intervals of normal women. Basal dehydroepiandrosterone sulphate and testosterone levels were also measured in hirsute women. All samples were obtained during the follicular phase of the menstrual cycle. ACTH stimulated hormone values and ratios were diagnostic for 3 beta HDS deficit in 7.5% of hirsute women. Basal testosterone was over 80 ng/dl in 47.5% and dehydroepiandrosterone sulphate over 3.9 micrograms/ml in 52.5% of these women. There was no correlation between dehydroepiandrosterone or testosterone values and ACTH stimulated hormone values. It is concluded that 3 beta HSD is frequent in hirsute women and that its diagnosis requires the determination of ACTH stimulated 17 hydroxypregnenolone values and 17 hydroxypregnenolone/17 hydroxyprogesterone ratio.

Assuntos

3-Hidroxiesteroide Desidrogenases/deficiência , Hirsutismo/enzimologia , 17-alfa-Hidroxipregnenolona/sangue , Hormônio Adrenocorticotrópico/administração & dosagem , Biomarcadores/sangue , Estudos de Casos e Controles , Chile , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Feminino , Humanos , Hidrocortisona/sangue , Hidroxiprogesteronas/sangue , Radioimunoensaio , Testosterona/sangue

RESUMO

Previous studies in our laboratory have identified a portion of big-big GH as actually being anti-GH receptor immunoglobulins. We now report the isolation of two types of anti-GH receptor antibodies from the serum of active acromegalic patients. One of them (patient A) interferes with the human GH RIA, thus overestimating the real plasma GH values. The other type of immunoglobulin G (IgG; patient B) was detected in an acromegalic patient with almost normal immunoreactive GH level. The main aim of the present study was to explore whether these anti-GH receptor IgGs possess GH-like biological activity. The IgGs of both patients were isolated by chromatography on Sephadex G-100 and then on protein-A-Sepharose. In the bioassay, cultured Nb2 lymphoma cells were incubated with hGH standards and serial dilutions of the purified IgGs, and cell proliferation was used as a measure of biological activity. The IgGs of both patients showed GH-like bioactivities, which, when calculated as equivalents of human GH, correspond to approximately 260 and 120 micrograms/L, respectively. The results suggest that biologically active anti-GH receptor antibodies may contribute in the pathology of some cases of acromegaly.

Assuntos

Acromegalia/fisiopatologia , Anticorpos/análise , Hormônio do Crescimento/fisiologia , Receptores da Somatotropina/imunologia , Acromegalia/sangue , Adolescente , Anticorpos/imunologia , Anticorpos/fisiologia , Feminino , Hormônio do Crescimento/sangue , Humanos , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Imunoglobulina G/fisiologia , Linfoma/química , Linfoma/patologia , Linfoma/ultraestrutura , Masculino , Pessoa de Meia-Idade , Radioimunoensaio , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/patologia , Células Tumorais Cultivadas/ultraestrutura

RESUMO

Serum osteocalcin (OC) was serially measured along an ovulatory menstrual cycle in 4 healthy unmedicated volunteers (age 33-38 years). During the study the women maintained their normal diet and daily physical activity. Starting at days 4-5 of the cycle, blood samples were taken between 09-11 AM every 2 or 3 days for OC, FSH, LH, E2 and P determinations. Daily ultrasound assessment of ovulation was performed in all subjects between days 7-18 of the cycle. Hormone determinations and OC were performed by RIA. While blood levels of FSH, LH, E2 and P changed during the cycle, according to the expected ovulatory pattern, serum OC concentrations remained stable during the cycle in each subject. In conclusion, serum OC is independent of the gonadotropin and ovarian steroid variations during the normal menstrual cycle.

Assuntos

Ciclo Menstrual/sangue , Osteocalcina/sangue , Adulto , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Fósforo/sangue , Radioimunoensaio

RESUMO

Serum osteocalcin (OC) was serially measured along an ovulatory menstrual cycle in 4 healthy unmedicated volunteers (age 33-38 years). During the study the women maintained their normal diet and daily physical activity. Starting at days 4-5 of the cycle, blood samples were taken between 09-11 AM every 2 or 3 days for OC, FSH, LH, E2 and P determinations. Daily ultrasound assessment of ovulation was performed in all subjects between days 7-18 of the cycle. Hormone determinations and OC were performed by RIA. While blood levels of FSH, LH, E2 and P changed during the cycle, according to the expected ovulatory pattern, serum OC concentrations remained stable during the cycle in each subject. In conclusion, serum OC is independent of the gonadotropin and ovarian steroid variations during the normal menstrual cycle.