RESUMO
OBJECTIVES: Since the Landmark Shelby V. Holder Supreme Court Ruling, the number of laws in the United States that make it difficult to vote has increased dramatically. This may lead to legislation that limits access to health care, including options for family planning services. We determine whether voting restrictions are associated with county-level teenage birth rates. STUDY DESIGN: This is an ecological study. METHODS: The Cost of Voting Index, a state-level measure of barriers to voting during US elections from 1996 to 2016, was used as a proxy for access to voting. County-level teenage birth rates were obtained from the County Health Rankings data. We used multilevel modeling to determine whether restrictive voting laws were associated with county-level teenage birth rates. We tested whether associations varied across racial and socio-economic groups. RESULTS: When confounders were included, a significant association was observed between increasing voting restrictions and teenage birth rates (ß = 1.72, 95% confidence interval: 0.54, 2.89). A Cost of Voting Index-median income interaction term was tested and was statistically significant (ß = -1.00, 95% confidence interval: -1.36, -0.64), indicating that the observed relationship was particularly strong among lower-income counties. The number of reproductive health clinics per capita within each state is a potential mediator. CONCLUSION: Restrictive voting laws were associated with higher teenage birth rates, particularly for low-income counties. Future work should use methods in which a causal relation can be identified.
Assuntos
Coeficiente de Natalidade , Renda , Adolescente , Humanos , Estados Unidos/epidemiologia , Serviços de Planejamento Familiar , Desigualdades de Saúde , PolíticaRESUMO
The Wilms' tumor locus (WTL) at 11p13 contains a gene that encodes a zinc finger-containing protein that has characteristics of a DNA-binding protein. However, binding of this protein to DNA in a sequence-specific manner has not been demonstrated. A synthetic gene was constructed that contained the zinc finger region, and the protein was expressed in Escherichia coli. The recombinant protein was used to identify a specific DNA binding site from a pool of degenerate oligonucleotides. The binding sites obtained were similar to the sequence recognized by the early growth response-1 (EGR-1) gene product, a zinc finger-containing protein that is induced by mitogenic stimuli. A mutation in the zinc finger region of the protein originally identified in a Wilms' tumor patient abolished its DNA-binding activity. These results suggest that the WTL protein may act at the DNA binding site of a growth factor-inducible gene and that loss of DNA-binding activity contributes to the tumorigenic process.
Assuntos
Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Genes do Tumor de Wilms , Proteínas Imediatamente Precoces , Fatores de Transcrição/metabolismo , Dedos de Zinco , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , Cromossomos Humanos Par 11 , Sequência Consenso , DNA/genética , Proteínas de Ligação a DNA/genética , Proteína 1 de Resposta de Crescimento Precoce , Escherichia coli/genética , Humanos , Dados de Sequência Molecular , Mutação , Oligonucleotídeos/metabolismo , Reação em Cadeia da Polimerase , Proteínas Recombinantes/metabolismo , Mapeamento por Restrição , Fatores de Transcrição/genética , Dedos de Zinco/genéticaRESUMO
The wt1 gene, a putative tumor suppressor gene located at the Wilms tumor (WT) locus on chromosome 11p13, encodes a zinc finger-containing protein that binds to the same DNA sequence as EGR-1, a mitogen-inducible immediate-early gene product that activates transcription. The transcriptional regulatory potential of WT1 has not been demonstrated. In transient transfection assays, the WT1 protein functioned as a repressor of transcription when bound to the EGR-1 site. The repression function was mapped to the glutamine- and proline-rich NH2-terminus of WT1; fusion of this domain to the zinc finger region of EGR-1 converted EGR-1 into a transcriptional repressor.
Assuntos
Proteínas de Ligação a DNA/genética , Genes Supressores de Tumor , Neoplasias Renais/genética , Proteínas Repressoras/genética , Transcrição Gênica , Tumor de Wilms/genética , Dedos de Zinco/genética , Sequência de Aminoácidos , Sequência de Bases , Linhagem Celular , Cromossomos Humanos Par 11 , DNA/genética , Regulação da Expressão Gênica , Humanos , Dados de Sequência MolecularRESUMO
The chromosome 11p13 Wilms' tumor locus (wt1) encodes a zinc finger-containing transcription factor (WT1). WT1 binds to the consensus sequence (5'-GCGGGGGCG-3') and represses transcription when bound to this site in vivo. The mechanism of repression is not yet defined. To investigate the mechanisms of transcriptional repression and map the domains of WT1 responsible, we constructed hybrid proteins between the yeast GAL4 1-147 DNA binding domain and WT1. Fusion of a 298 amino acid glutamine-proline-rich N-terminal segment of WT1 to the GAL4 DNA binding domain created a potent transcriptional repressor. The use of N- and C-terminal truncations of this segment demonstrated that as few as 96 amino acids were required for active repression by GAL4-WT1 hybrid proteins in NIH3T3 fibroblasts. However, the truncated GAL4-WT1 fusion proteins functioned poorly as repressors in embryonic kidney-derived 293 cells, suggesting cell type-specific requirements for transcriptional repression. Site-directed mutagenesis of the WT1 repression domain revealed that deletion of homopolymeric proline and glycine regions, as well as single amino acid changes, partially inactivated the repression function. Single repressor binding sites placed upstream of the transcription start site conferred WT1-mediated repression to a heterologous promoter, whereas multiple sites resulted in additive (non-synergistic) increases in transcriptional repression. Significant repression of transcription was observed when binding sites were placed 760 base pairs upstream or 1000 base pairs downstream relative to the site of transcription initiation. We conclude that the transcriptional repression function of WT1 is contained in the N-terminal, non-DNA binding domain of the protein and that repression can be functionally transferred to a heterologous DNA binding domain.
Assuntos
Proteínas de Ligação a DNA/farmacologia , Proteínas Repressoras/farmacologia , Transcrição Gênica/efeitos dos fármacos , Dedos de Zinco , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Sítios de Ligação , DNA/metabolismo , Proteínas de Ligação a DNA/química , Camundongos , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Proteínas Recombinantes de Fusão/farmacologia , Relação Estrutura-Atividade , Proteínas WT1RESUMO
The Wilms' tumor suppressor gene (wt1) encodes a zinc finger DNA binding protein (WT1) which functions as a transcriptional regulator and is essential for normal urogenital development. WTI has previously been shown to repress the transcription of a variety of target genes whose products stimulate growth, such as growth factors, growth factor receptors and other transcription factors. In this study, we identify syndecan-1 as a target gene for WT1-mediated activation. Syndecan-1 is a cell surface proteoglycan whose induction is coincident with epithelial differentiation during kidney development and whose loss of expression is correlated with the loss of the epithelial phenotype and malignant transformation. The murine syndecan-1 promoter contains several potential binding sites for WT1. We demonstrate that both WT1 (-KTS) and WT1 (+KTS) isoforms bind to multiple sites in this highly G + C-rich region, as detected by gel-shift analyses. These WT1 isoforms function as transcriptional activators of syndecan-1 expression in transient transfection assays. Activation of syndecan-1 by WT1 is dependent on an intact zinc-finger region as well as a 179 amino acid proline-rich region in the amino terminus of the protein. Moreover, the endogenous syndecan-1 gene is activated by WT1 in a novel inducible cell line based upon the sheep metallothionein promoter. These results highlight an emerging role for WT1 as an activator of genes like syndecan-1 which may potentiate epithelial differentiation and maintenance in the developing kidney.
Assuntos
Proteínas de Ligação a DNA/fisiologia , Genes do Tumor de Wilms , Glicoproteínas de Membrana/genética , Regiões Promotoras Genéticas , Proteoglicanas/genética , Fatores de Transcrição/fisiologia , Ativação Transcricional , Células 3T3 , Animais , Sequência de Bases , DNA , Humanos , Camundongos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , RNA Mensageiro/genética , Sindecana-1 , Sindecanas , Proteínas WT1 , Dedos de ZincoRESUMO
We analysed the biochemical properties of the transcription factor encoded by the putative tumor-suppressor gene present at the WT1 Wilms' tumor locus. A gene containing the full-length amino acid coding sequence of human wt1 was reconstructed from synthetic oligonucleotides and cloned into expression vectors for in vitro and in vivo protein synthesis. Polyclonal rabbit antibodies specific for the WT1 protein were raised to an Escherichia coli-produced 91 amino acid N-terminal segment and to a 136 amino acid C-terminal segment, which contains the zinc finger domain. WT1 produced by in vitro translation migrated as a 52 kDa protein on sodium dodecylsulfate-polyacrylamide gels and bound to the EGR consensus sequence in gel-retardation assays. Expression of the wt1 gene via transient transfection in COS-1 cells revealed a 52 kDa protein which was immunoprecipitated by both the N-terminal- and C-terminal-specific antisera. Immunofluorescence studies of wt1-transfected COS-1 cells revealed that the WT1 protein was localized to the nucleus. Metabolic labeling with [32P]orthophosphate failed to reveal significant phosphorylation of the WT1 protein in COS-1 cells. Two immunoreactive WT polypeptides of 52 and 54 kDa were observed in murine embryonic stem cells and COS-1 kidney cells and may represent previously identified splicing variants of WT1. These antisera should be useful in characterizing the structure and function of the WT1 protein in human Wilms' tumor specimens.
Assuntos
Genes Supressores de Tumor , Neoplasias Renais/genética , Tumor de Wilms/genética , Dedos de Zinco/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/genética , Imunofluorescência , Humanos , Metionina/metabolismo , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos , Mapeamento de Peptídeos , Proteínas Recombinantes/análise , Proteínas Recombinantes/metabolismo , TransfecçãoRESUMO
One woman (patient 1), aged 27 years, and one man (patient 2), aged 26 years, had pituitary surgery for pituitary-dependent Cushing's syndrome. An adenoma was identified and removed in both patients. Persistence of hypercortisolism characterized the response of patient 2 to surgery; transient hypoadrenalism, the response of patient 1. Patient 1 subsequently underwent a relapse. At the second surgery (total hypophysectomy for both patients), hyperplasia was demonstrated in patient 1, and scattered nests of adrenocorticotropic hormone (ACTH)-secreting cells were demonstrated in patient 2. Postoperatively, Cushing's syndrome persisted in both patients. Inferior petrosal sampling for ACTH during corticotropin releasing hormone stimulation verified a pituitary source of ACTH in patient 1. A decrease in cortisol secretion following hypophysectomy and subsequent cure by pituitary irradiation constitutes the evidence for pituitary origin in patient 2. Dexamethasone suppression and corticotropin releasing hormone-stimulation tests consistently suggested a pituitary cause throughout the clinical course of both patients. Computed tomographic scans after hypophysectomy revealed postoperative changes only. In both patients, panhypopituitarism, except for cortisol and ACTH, followed hypophysectomy. It may be concluded that patients with diffuse pituitary ACTH hyperplasia cannot, at present, be identified preoperatively by conventional clinical testing. Surgery for such patients may not be the therapy of choice.
Assuntos
Adenoma/cirurgia , Síndrome de Cushing/cirurgia , Hipofisectomia , Neoplasias Hipofisárias/cirurgia , Adenoma/complicações , Adulto , Síndrome de Cushing/etiologia , Síndrome de Cushing/metabolismo , Feminino , Humanos , Masculino , Neoplasias Hipofisárias/complicações , Testes de Função Adreno-HipofisáriaRESUMO
Large, adrenocorticotrophic hormone-secreting pituitary tumors (Nelson's syndrome) developed in four of 12 patients treated with a bilateral adrenalectomy for Cushing's disease. Two of the patients with Nelson's syndrome suffered spontaneous pituitary tumor infarctions. One patient improved under close observation and subsequent radiation therapy, although she ultimately died from her locally invasive tumor. The condition of the other patient-which had stabilized-appeared to be worsened by surgical intervention. The high incidence of these tumors after bilateral adrenalectomy, their large and agressive nature, and their apparent propensity to undergo spontaneous infarction supports the position that initial therapy for Cushing's disease should be directed to the pituitary gland.
Assuntos
Infarto/etiologia , Síndrome de Nelson/complicações , Neoplasias Hipofisárias/irrigação sanguínea , Neoplasias Hipofisárias/complicações , Adrenalectomia/efeitos adversos , Adulto , Síndrome de Cushing/cirurgia , Feminino , Humanos , Síndrome de Nelson/etiologia , Síndrome de Nelson/radioterapia , Síndrome de Nelson/cirurgia , Neoplasias Hipofisárias/radioterapia , Neoplasias Hipofisárias/cirurgiaRESUMO
A woman with pituitary-dependent Cushing's disease remained hypercortisolemic after bilateral adrenalectomy. A search for an adrenal remnant by venous catheterization study suggested persistent cortisol-secreting tissue in the left adrenal bed. During ACTH stimulation, plasma corticosterone concentrations remained low and cortisol remained high, suggesting the cortisol was of exogenous origin. Cushingoid features resolved after confronting the patient with this evidence. Plasma corticosterone concentrations played a novel role in the diagnosis of factitiously induced Cushing's syndrome in this patient.
Assuntos
Síndrome de Cushing/diagnóstico , Transtornos Autoinduzidos/diagnóstico , Hormônio Adrenocorticotrópico , Adulto , Corticosterona/sangue , Síndrome de Cushing/sangue , Transtornos Autoinduzidos/sangue , Feminino , Humanos , Hidrocortisona/sangueRESUMO
Although changes in hypothalamic-pituitary-adrenal axis function have frequently been reported in alcoholics, the majority of studies have used recently detoxified subjects in whom abstinence phenomena and clinical depression may contribute to observed stress axis alterations. To isolate the primary effects of alcohol dependence on the stress axis, the ACTH and cortisol responses to insulin-induced hypoglycemia were measured in seven actively drinking male alcoholics recruited from the general public through a newspaper advertisement along with eight age-matched male controls. The alcoholic subjects met current American Psychiatric Association diagnostic criteria for alcohol dependence, were stably employed, and had no concurrent psychiatric disorders, cognitive impairment, or psychometric evidence of depression. While relatively young (30.0 yr; range, 22-48 yr), they had lengthy histories of alcohol-related problems (11.9 yr; range, 5-30 yr). Insulin administration resulted in similar nadirs in blood sugar in both alcoholic and control groups. However, the plasma ACTH response was markedly blunted in the alcoholics (P = 0.040, by Mann-Whitney U test). There was a nonsignificant trend toward increased cortisol levels in the alcoholic group. The findings suggest that altered hypothalamic-pituitary-adrenal axis function in alcoholics is a primary results of chronic ethanol exposure rather than a confounding effect of clinical depression or recent detoxification.
Assuntos
Hormônio Adrenocorticotrópico/sangue , Consumo de Bebidas Alcoólicas/fisiologia , Alcoolismo/sangue , Etanol/farmacologia , Hipoglicemia/sangue , Insulina/administração & dosagem , Adulto , Alcoolismo/fisiopatologia , Glicemia/análise , Depressão/sangue , Humanos , Hidrocortisona/sangue , Hipoglicemia/induzido quimicamente , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/fisiologiaRESUMO
We prospectively studied two groups of GH-deficient patients during GH therapy based upon exposure of the liver to elevated (oral estrogen) or not elevated (endogenous or transdermal) sources of estrogen. We wondered whether higher concentrations of estrogen at the liver level (oral estrogen) might inhibit insulin-like growth factor I (IGF-I) secretion and alter exogenous GH requirements. In this study we compared GH replacement requirements in these two groups of women as well as with GH-treated adult hypopituitary males. The final GH dose was based upon maintenance IGF-I levels in the mid- to high normal range adjusted for age and sex or symptom tolerance. Each group [women taking oral estrogen (n = 12), women not taking oral estrogen (n = 13), and men (n = 12)] was similar in age and final IGF-I concentration. Women taking oral estrogen required 10.6 +/- 0.7 microg/kg x day or 867 +/- 45 microg/day GH, women not taking oral estrogen required 5.0 +/- 0.7 microg/kg x day or 424 +/- 57 microg/day, and men required 4.1 +/- 0.6 microg/kg x day or 376 +/- 49 microg/day to achieve similar IGF-I concentrations. GH requirements in men were not different from those in women not taking oral estrogen, but the GH requirements in both groups were significantly different from GH requirements in women taking oral estrogen. These observations may be useful in anticipating appropriate starting and final doses of GH in adult hypopituitary patients.
Assuntos
Estradiol/administração & dosagem , Hormônio do Crescimento Humano/administração & dosagem , Hormônio do Crescimento Humano/deficiência , Administração Cutânea , Administração Oral , Adulto , Feminino , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
Recently, intraoperative rapid immunochemiluminometric assay (ICMA) ACTH measurements have been used to evaluate the completeness of resection of ectopic ACTH-secreting tumors. This study evaluates whether this method can be applied to patients undergoing transsphenoidal surgery (TSS) for Cushing's disease to predict complete pituitary tumor resection. Eighteen patients with Cushing's disease undergoing TSS had plasma ACTH concentrations measured by a standard ICMA every 10 min for 1 h immediately after pituitary tumor removal. Patients were evaluated postoperatively for cure by standard criteria. ACTH levels were evaluated for percentage decrease from baseline at each time point. Patients who were cured (n = 11) had statistically greater decreases in ACTH levels (mean decrease 54%) than patients who were not (n = 7; 26% mean decrease, P < 0.04). By Receiver-Operator Characteristic (ROC) analysis, a reduction of at least 40% best predicted which patients were cured and which were not cured. This level of reduction was observed in 82% of cured patients, and a reduction of less than 40% was observed in 71% of those not cured. The analysis misclassified 4 of the 18 patients, resulting in a diagnostic accuracy of 78%. Although the mean maximal decrease in ACTH concentrations after tumor removal was significantly different between cured and not cured patients with Cushing's disease, it was less dramatic than results in the previous ectopic ACTH study. This may relate to incomplete suppression and/or surgical manipulation of normal pituitary corticotrophs in patients with pituitary disease. In summary, in contrast to the ectopic ACTH syndrome, decline of plasma ACTH during TSS does not accurately predict complete tumor resection.
Assuntos
Hormônio Adrenocorticotrópico/sangue , Síndrome de Cushing/sangue , Síndrome de Cushing/cirurgia , Feminino , Humanos , Técnicas Imunológicas , Período Intraoperatório , Medições Luminescentes , Masculino , Prognóstico , Estudos Prospectivos , Fatores de Tempo , Resultado do TratamentoRESUMO
A 17-year-old women received 12,000 rads of alpha-particle radiation for the treatment of Cushing's disease. One day after the completion of therapy, the patient developed nausea, vomiting, headache, and postural hypotension. Laboratory evaluation demonstrated a marked fall of the previously elevated urinary 17-hydroxycorticosteroids (17-OHCS) and undetectable plasma cortisols. The urinary 17-OHCS transiently returned to supranormal levels but over a 2 1/2-week period decreased and then remained low. The patient also demonstrated a subnormal urinary aldosterone excretion in relation to plasma renin activity (PRA) during 10 mEq/24 h sodium restriction. The remainder of the endocrine evaluation was normal, suggesting that pituitary function otherwise remained intact. One and one-half years after alpha-particle therapy, the patients's urinary 17-OHCS were normal and responded normally to metyrapone. The relationship between urinary aldosterone excretion and PRA also was normal. It is postulated that there was an infarction of an ACTH secreting pituitary tumor leaving the remainder of the pituitary intact. Achronically elevated circulating level of ACTH with sudden loss of ACTH secretion appeared to have been responsible for the initial low urinary aldosterone as well as the low urinary 17-OHCS. This is the first reported case of a presumed pituitary tumor infarction in association with alpha-particle pituitary radiation.
Assuntos
Insuficiência Adrenal/etiologia , Partículas alfa , Síndrome de Cushing/radioterapia , 17-Hidroxicorticosteroides/urina , Adenoma/irrigação sanguínea , Adenoma/metabolismo , Adolescente , Insuficiência Adrenal/metabolismo , Hormônio Adrenocorticotrópico/metabolismo , Aldosterona/urina , Feminino , Humanos , Hidrocortisona/sangue , Infarto , Neoplasias Hipofisárias/irrigação sanguínea , Neoplasias Hipofisárias/metabolismo , Renina/sangueRESUMO
It can be difficult to establish the diagnosis of Cushing's Syndrome (CS) in patients with mild or nonspecific clinical and biochemical findings, because available diagnostic tests have limited predictive values. We hypothesized that measurement of 24-h cortisol production rates (CPRs) might be a more sensitive indicator of CS in such patients. We measured CPRs in 28 patients with suspected CS (but equivocal biochemical findings) and in 22 healthy control subjects, by infusing tracer amounts of deuterated cortisol, with simultaneous measurements of 24-h urine free cortisol (UFC) levels; and we frequently sampled serum cortisol levels. CPRs were calculated from the ratio of isotopic enrichment to isotopic dilution of cortisol measured by gas chromatography-negative ion chemical ionization mass spectrometry. Nine of the patients proved to have CS by surgery (CS-Yes), whereas 19 patients were determined not to have CS by biochemical testing (CS-No). Mean 24-h UFCs, nocturnal serum cortisol levels, and CPRs were higher in CS-Yes, compared with CS-No and normal subjects. However, one CS-Yes patient had a normal 24-h UFC, two had normal nocturnal serum cortisol levels, and two had normal 24-h CPRs. There was extensive overlap in all of the biochemical parameters between the CS-Yes and the CS-No groups. Thus, measurement of CPR does not seem to offer any diagnostic advantage over available tests for the diagnosis of CS. Patients with proven CS can have normal UFC levels, normal CPRs, or normal nocturnal cortisol levels, whereas patients not thought to have CS may have elevated levels of any one or more these parameters.
Assuntos
Síndrome de Cushing/sangue , Síndrome de Cushing/diagnóstico , Hidrocortisona/sangue , Adulto , Idoso , Cromatografia Gasosa , Ritmo Circadiano/fisiologia , Deutério , Feminino , Humanos , Hidrocortisona/urina , Masculino , Pessoa de Meia-Idade , Técnica de Diluição de Radioisótopos , Análise de Regressão , Análise EspectralRESUMO
Inferior petrosal sinus sampling (IPSS) is used to distinguish pituitary Cushing's disease from occult cases of the ectopic ACTH syndrome, but is limited in that it requires the use of ovine CRH (oCRH) and is not highly accurate at predicting the intrapituitary location of tumors. This study was designed to determine whether cavernous sinus sampling (CSS) is as safe and accurate as IPSS, whether CSS can eliminate the need for oCRH stimulation, and whether CSS can accurately predict the intrapituitary location of tumors. Ninety-three consecutive patients with ACTH-dependent Cushing's syndrome were prospectively studied with bilateral, simultaneous CSS before and after oCRH stimulation. Prediction of a pituitary or ectopic ACTH source was based on cavernous/peripheral plasma ACTH ratios. Intrapituitary tumor location was predicted based on lateralization (side to side) ACTH ratios. These predictions were compared to surgical outcome in the 70 patients who had surgically proven pituitary (n = 65) or ectopic (n = 5) disease. CSS distinguished pituitary Cushing's disease from the ectopic ACTH syndrome in 93% of patients with proven tumors before oCRH administration and in 100% of patients with proven tumors after oCRH. It was as safe and efficacious as published IPSS results. CSS accurately predicted the intrapituitary lateralization of the tumor in 83% of all patients and 89% of those patients with good catheter position and symmetric venous flow. CSS is as safe and accurate as IPSS for distinguishing patients with pituitary Cushing's disease from those with the ectopic ACTH syndrome. In addition, CSS appears to be superior to IPSS for predicting intrapituitary tumor lateralization.
Assuntos
Síndrome de ACTH Ectópico/diagnóstico , Seio Cavernoso/diagnóstico por imagem , Síndrome de Cushing/diagnóstico , Neoplasias Hipofisárias/diagnóstico , Síndrome de ACTH Ectópico/diagnóstico por imagem , Síndrome de ACTH Ectópico/cirurgia , Hormônio Adrenocorticotrópico/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Hormônio Liberador da Corticotropina , Síndrome de Cushing/diagnóstico por imagem , Síndrome de Cushing/cirurgia , Diagnóstico Diferencial , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Hipófise/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Prospectivos , Radiografia , Ovinos , Resultado do TratamentoRESUMO
Extremely premature infants manifest clinical features suggestive of adrenal insufficiency. Yet, serum cortisol levels are similar in ill and well preterm infants in a setting where one would expect high stress levels in the ill infants. We investigated the hypothalamic-pituitary-adrenal axis in 17 extremely low birth weight stressed premature infants, mean birth weight 739 g, gestational age, 26.1 weeks, using ovine CRH (oCRH) and ACTH stimulation. oCRH (1 microgram/kg) was administered at 2-7 days of life (mean = 4.1). ACTH rose from a basal value 6.0 +/- 0.8 pmol/L (mean +/- SEM) to 9.6 +/- 1.8 pmol/L (P < 0.01) at 15 min and 9.5 +/- 1.7 pmol/L (P < 0.01) at 60 min. Basal cortisol rose from 349.3 +/- 58.1 nmol/L to 422.3 +/- 57.9 nmol/L (P < 0.01) at 15 min and 568.7 +/- 60.2 nmol/L (P < 0.01) at 60 min. Cortisol values remained significantly (P < 0.05) elevated 24 h after oCRH. An ACTH stimulation test performed 24 h after the oCRH test demonstrated a significant cortisol rise from 603.5 +/- 130.5 nmol/L to 882.7 +/- 136.6 nmol/L (P < 0.05) at 60 min. Plasma CRH immunoactivity was also measured before oCRH testing and was detectable in 10 of 15 infants. The mean CRH immunoactivity was 21.8 +/- 4.4 pmol/L in the infants, significantly higher than 8 adult male controls (P < 0.04). Our results show a normal pituitary response to ovine CRH and a normal adrenal response to ACTH. We hypothesize that cortisol levels are inappropriately low in some ill preterm infants because of the inability of the extremely premature brain to recognize the stress of the illness or because of inadequate hypothalamic secretion of CRH. The significance of the measurable plasma CRH in the first week of life is unknown.
Assuntos
Glândulas Suprarrenais/fisiologia , Hipotálamo/fisiologia , Recém-Nascido de Baixo Peso/fisiologia , Recém-Nascido Prematuro/fisiologia , Hipófise/fisiologia , Hormônio Adrenocorticotrópico/sangue , Hormônio Liberador da Corticotropina/sangue , Idade Gestacional , Humanos , Hidrocortisona/sangue , Recém-Nascido , MasculinoRESUMO
A pharmacokinetic-pharmacodynamic study of a long-acting GH [Nutropin Depot; somatropin (rDNA origin) for injectable suspension] was performed in 25 patients with adult GH deficiency. Single doses of 0.25 mg/kg and 0.5 mg/kg, based on ideal body weight, were administered sc. After either dose, serum GH concentrations rose rapidly in both sexes. In men, the lower dose maintained serum IGF-I levels within 1 SD of the mean for age and sex for 14-17 d; the higher dose raised IGF-I levels 2 SD above the mean. In most women, all of whom were receiving oral estrogen, the lower dose did not normalize IGF-I levels; the higher dose maintained IGF-I near the mean for approximately 14 d. Increases in IGF binding protein-3 and acid-labile subunit levels were observed in both sexes; however, a sex-related difference was not obvious. Fasting glucose and insulin concentrations were transiently elevated in men receiving the higher dose. Patients tolerated the injections well. We concluded that a single injection of Nutropin Depot at these doses in patients with adult GH deficiency increased serum IGF-I to within normal limits for 14-17 d. Estrogen-treated women required approximately twice the dose needed in men to produce comparable IGF-I concentrations.
Assuntos
Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/farmacocinética , Adulto , Idoso , Glicemia/análise , Proteínas de Transporte/sangue , Preparações de Ação Retardada , Jejum , Feminino , Glicoproteínas/sangue , Hormônio do Crescimento Humano/sangue , Hormônio do Crescimento Humano/farmacologia , Humanos , Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Cinética , Masculino , Pessoa de Meia-Idade , Caracteres SexuaisRESUMO
In a group of 19 patients with pituitary dysfunction, we assessed peripheral visual fields and flicker discrimination. Two subgroups of patients were defined: (1) nonsurgical (n = 6), and (2) surgical (n = 13). For the nonsurgical group, 16.7% (2/12) of the eyes tested had impaired flicker discrimination, whereas 33% (4/12) had a deficit in visual field. For the surgical group, none of the patients had a deficit of visual field, whereas 60% (15/25) of the eyes tested had an alteration of flicker discrimination. For this latter group, abnormalities of the flicker fusion threshold were present several months to several years after surgery.
Assuntos
Hipotálamo , Hipófise , Transtornos da Visão/diagnóstico , Adulto , Encefalopatias/complicações , Encefalopatias/etiologia , Feminino , Humanos , Masculino , Neoplasias Hipofisárias/cirurgia , Complicações Pós-Operatórias , Transtornos da Visão/complicações , Testes VisuaisRESUMO
This review article discusses the diagnostic possibilities that might result in an adrenal mass lesion and suggests the most appropriate diagnostic evaluation to verify the most likely cause. An algorithm is formulated for lesions that do not have a clinically apparent reason after initial evaluation, an unfortunately frequent situation.
Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Glândulas Suprarrenais/anatomia & histologia , Glândulas Suprarrenais/diagnóstico por imagem , Glândulas Suprarrenais/patologia , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/fisiopatologia , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/fisiopatologia , Feocromocitoma/diagnóstico , Feocromocitoma/fisiopatologia , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Surgical exploration for gastrinoma has a high failure rate because of small primary tumors and occult metastasis. Despite extensive preoperative and intraoperative tumor localization, only 30% to 40% of patients with gastrinoma are cured by surgery. Two patients with unlocalized gastrinomas were studied with intraoperative gamma detection of an iodine 125-labeled somatostatin analog, lanreotide, to localize their tumors. METHODS: Both patients were challenged before operation with 100 micrograms of octreotide acetate, and both had circulating gastrin levels suppressed by greater than 50%. Iodine 125-labeled lanreotide (100 to 150 muCi) was injected during exploration, and an intraoperative gamma detector was used to detect tumor binding of the analog. RESULTS: In patient 1 a single source of increased counts was discovered in a retroduodenal lymph node, which was excised; no other tissue was removed. Histologic study of this node failed to demonstrate tumor; however, the patient's gastrin level was normal (63 pg/ml) 4 months after operation. In patient 2 five areas of increased counts were discovered and excised. Three of these five areas had visible tumor on microscopic examination. Three months after operation the patient's fasting gastrin level was 103 pg/ml. CONCLUSIONS: Intraoperative gamma detection of radiolabeled peptides may allow the localization of occult tumors that contain specific peptide receptors.