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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Congenital adrenal hyperplasia describes a group of inherited autosomal recessive disorders characterized by an enzymatic defect in cortisol biosynthesis, compensatory increases in corticotropin secretion, and adrenocortical hyperplasia. 21-Hydroxylase deficiency is responsible for more than 95% of cases and is one of the most common known autosomal recessive disorders. The classic or severe type presents in the newborn period or early childhood with virilization and adrenal insufficiency, with or without salt loss; the mild or nonclassic form presents in late childhood or early adulthood with mild hyperandrogenism and is an important cause of masculinization and infertility in women. This wide range of phenotypic expression is mostly explained by genetic variation, although genotype-phenotype discrepancies have been described. Reproductive, metabolic, and other comorbid conditions, including risk for tumors, are currently under investigation in both forms of the disease. A high proportion of patients with adrenal incidentalomas may be homozygous or heterozygous for 21-hydroxylase deficiency. Women with congenital adrenal hyperplasia often develop the polycystic ovary syndrome. Ectopic adrenal rest tissue is often found in the testes of men with congenital adrenal hyperplasia; characteristic clinical and radiologic findings help differentiate this tissue from other tumors. Levels of corticotropin-releasing hormone are elevated in patients with depression and anxiety and are expected to be elevated in patients with congenital adrenal hyperplasia; it is unknown whether patients with 21-hydroxylase deficiency have an increased incidence of these psychiatric disorders. Abnormalities in both the structure and function of the adrenal medulla have been shown in patients with classic congenital adrenal hyperplasia, and the degree of adrenomedullary impairment may be a biomarker of disease severity. The 21-hydroxylase-deficient mouse has provided a useful model with which to examine disease mechanisms and test new therapeutic interventions in classic disease, including gene therapy. Treatment of this condition is intended to reduce excessive corticotropin secretion and replace both glucocorticoids and mineralocorticoids. However, clinical management is often complicated by inadequately treated hyperandrogenism, iatrogenic hypercortisolism, or both. New treatment approaches currently under investigation include combination therapy to block androgen action and inhibit estrogen production, and bilateral adrenalectomy in the most severely affected patients. Other approaches, which are in a preclinical stage of investigation, include treatment with a corticotropin-releasing hormone antagonist and gene therapy.
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PMID:NIH conference. Future directions in the study and management of congenital adrenal hyperplasia due to 21-hydroxylase deficiency. 1184 30

The most potent corticosteroids are 11beta-hydroxylated compounds. In humans, two cytochrome P450 isoenzymes with 11beta-hydroxylase activity, catalyzing the biosynthesis of cortisol and aldosterone, are present in the adrenal cortex. CYP11B1, the gene encoding 11beta-hydroxylase (P450c11), is expressed in high levels in the zona fasciculata and is regulated by adrenocorticotropic hormone (ACTH). CYP11B2, the gene encoding aldosterone synthase (P450c11Aldo), is expressed in the zona glomerulosa under primary control of the renin-angiotensin system. The substrate for P450c11 is 11-deoxycortisol. Mutations in CYP11B1 cause congenital adrenal hyperplasia (CAH) due to 11beta-hydroxylase deficiency. This disorder is characterized by androgen excess and hypertension and is autosomal recessively inherited. Classical and nonclassical forms of 11beta-hydroxylase deficiency can be distinguished. Studies in heterozygotes for classical 11beta-hydroxylase deficiency show inconsistent results with no or only mild hormonal abnormalities (elevated plasma levels of 11-deoxycortisol after ACTH stimulation). Molecular genetic studies of the CYP11B1 gene in 11beta-hydroxylase deficiency have led to the identification of several mutations. Transfection experiments showed loss of enzyme activity in vitro. Molecular genetic studies have practical importance for the prenatal diagnosis of virilizing CAH forms.
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PMID:Congenital adrenal hyperplasia: 11beta-hydroxylase deficiency. 1242 5

The aim of the study was to compare the response between the standard and low dose adrenocorticotropin (ACTH) test for patients with congenital adrenal hyperplasia (CAH). The authors employed a 2-by-2 crossover design and enrolled 16 patients, 14 girls and 2 boys, aged between 1.4 months and 15 years. Steroid treatment was stopped 24 hours before each test was conducted. The standard ACTH (250 microg) test was performed followed by the low dose test (1 microg) in eight patients; the other eight underwent the low dose ACTH test first followed by the standard one. The cortisol and 17-hydroxyprogesterone (17-OHP) levels in each patient varied unpredictably between the two tests. The cortisol responses to the low dose ACTH at 30 and 60 minutes were lower than at time zero; in contrast to the 60-minute peak cortisol response to the standard dose. The serum 17-OHP in all specimens was more than 10,000 ng/dl (300 nmol/L), with the peak response at 60 minutes in both groups. Both the low dose and standard dose ACTH test indicated adrenal insufficiency and the high 17-OHP levels were diagnostic of 21- hydroxylase (21-OH) deficiency. If the low dose ACTH test becomes the "standard" ACTH test, the diagnosis of 21-OH deficiency would probably not be missed.
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PMID:Adrenocorticotropin stimulation test in congenital adrenal hyperplasia: comparison between standard and low dose test. 1294 58

Primary aldosteronism, congenital adrenal hyperplasia, Cushing's syndrome, glucocorticoid-remediable aldosteronism, and corticotropin-dependent forms of adrenal pathology can cause hypertension by excessive production of adrenocortical hormones. Although traditional biochemical assays continue to be used, genetic testing has simplified the diagnosis of glucocorticoid-remediable aldosteronism. Also, new interventional radiologic approaches for the diagnosis and treatment of corticotropin-dependent forms of Cushing's syndrome are available. Medical and surgical approaches, however, still remain viable options for treatment.
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PMID:Adrenocortical hypertension. 1648 Jun 76

Congenital adrenal hyperplasia is a general term applied to several disorders caused by inherited recessive defects of cortisol synthesis. The most common form is 21-hydroxylase deficiency, accounting for 95% of cases. The classical forms have an incidence of one in 15,000 and the non-classical forms about one in 1,000. The classical or severe phenotype presents in the newborn period or early infancy with virilization and adrenal insufficiency, with or without salt-losing; the non-classical or mild phenotype presents in late childhood or early adulthood with signs of hyperandrogenism. This wide range of clinical expression is explained by genetic variation. Although there is a certain amount of genotype-phenotype correlation, discrepancies have been described. During the last 30 years there has been a substantial improvement in diagnosis and treatment of this disease, and patients with CAH now reach adulthood. Treatment of this condition is intended to reduce excessive corticotropin secretion and replace glucocorticoids and mineralocorticoids as physiologically as possible. Clinical management is often complicated by periods of inadequately treated hyperandrogenism, iatrogenic hypercortisolism, or both. Long-term consequences in adult life may include short stature, obesity, diminished bone mass, gonadal dysfunction with low fertility rates and psychosexual dysfunction in females. New treatment approaches are under investigation, such as the use of anti-androgens, inhibitors of estrogen production and adrenalectomy for severely resistant cases.
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PMID:Childhood-onset congenital adrenal hyperplasia: long-term outcome and optimization of therapy. 1513 1

The measurement of 17alpha-hydroxyprogesterone (17alpha-OHPR) is of value for the diagnosis and management of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. In the central laboratory from 2000 to 2002, we observed, using the assay from the manufacturer DSL, an elevation of the moving average of 17alpha-OHPR concentrations and a number of adrenocorticotropic hormone (ACTH) stimulation tests despite the lack of any changes to the internal and external quality control, of which the criteria were continuously fulfilled. We studied a population of n=49 patients for the measurement of 17alpha-OHPR, with and without extraction, to evaluate the quality of different commercially available radioimmunoassays. The internal and external quality controls were successful in determining 17alpha-OHPR. An excellent measurement and correlation of 17alpha-OHPR was expressed with the assay from the manufacturer IBL without extraction and from the manufacturer DSL with extraction. The quantitative determination of 17alpha-OHPR requires adequate specificity and accuracy of the 17alpha-OHPR radioimmunoassays. The results show that internal and external quality control systems are not sufficient to resolve analytical problems described in this study.
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PMID:Comparison of three commercial assays for the measurement of 17alpha-hydroxyprogesterone (17alpha-OHPR): limitations of the quality control system. 1514 57

This article reports the case of a boy diagnosed at 1.8 years of age with congenital adrenal hyperplasia due to 11 beta-hydroxylase deficiency. The patient showed salt-wasting episodes during the neonatal period. On molecular analysis, a homozygous deletion hybrid (CYP11B2-CYP11B1) involving the CYP11B locus at 8q24.3 was found. Southern blot analysis showed the break point of the chimera gene to be located before intron 5; sequence analysis identified it at exon 4 between codons 202 and 248. This CYP11B2(5')/B1(3') hybrid should lack aldosterone synthase activity (due to the CYP11B1 residues at exons 5 and 6), and the enzyme it codes for should not be promoted by adrenocorticotropic hormone (ACTH) (CYP11B2 promoter sequences). The patient phenotype - neonatal salt-wasting and 11 beta-hydroxylase deficiency - is in agreement with this hybrid structure. This is the first time a homozygous deletion hybrid generated by unequal crossover has been described in exon 4. This genetic lesion appears to be the reciprocal product from the recombination event that causes glucocorticoid-remediable aldosteronism, a duplication dominant allele (CYP11B2-CYP11B1/B2-CYP11B1) coding for additional aldosterone synthase activity regulated by ACTH. The clinical presentation of the condition in this patient contributes to the in vivo understanding of the regulation of this complex locus in which two 'duplicated' genes have evolved different regulatory and enzymatic activities involved in mineralocorticoid and glucocorticoid synthesis in the adrenal glands. The fact that this allele was first predicted and has now been documented clinically and molecularly in vivo is particularly noteworthy.
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PMID:Neonatal salt-wasting and 11 beta-hydroxylase deficiency in a child carrying a homozygous deletion hybrid CYP11B2 (aldosterone synthase)-CYP11B1 (11 beta-hydroxylase). 1532 22

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders resulting from deficiency of one of the five enzymes required for synthesis of cortisol in the adrenal cortex. The most common form of the disease is classic 21-hydroxylase deficiency, which is characterized by decreased synthesis of glucocorticoids and often mineralocorticoids, adrenal hyperandrogenism and impaired development and function of the adrenal medulla. The clinical management of classic 21-hydroxylase deficiency is often suboptimal, and patients are at risk of developing in tandem iatrogenic hypercortisolism and/or hyperandogenism. Limitations of current medical therapy include the inability to control hyperandrogenism without employing supraphysiologic doses of glucocorticoid, hyperresponsiveness of the hypertrophied adrenal glands to adrenocorticotropic hormone (ACTH) and difficulty in suppressing ACTH secretion from the anterior pituitary. Puberty imposes increased difficulty in attaining adrenocortical suppression despite optimal substitution therapy and adherence to medical treatment. Alterations in the endocrine milieu at puberty may influence cortisol pharmacokinetics and, consequently, the handling of hydrocortisone used as replacement therapy. Recent studies have demonstrated a significant increase in cortisol clearance at puberty and a shorter half-life of free cortisol in pubertal females compared with males. Furthermore, children with classic CAH have elevated fasting serum insulin concentrations and insulin resistance. The latter may further enhance adrenal and/or ovarian androgen secretion, decrease the therapeutic efficacy of glucocorticoids and contribute to later development of the metabolic syndrome and its complications.
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PMID:Classic congenital adrenal hyperplasia and puberty. 1555 90

Adrenal myelolipomas are rare benign tumors that comprise mature adipose cells and hematopoietic elements. They are usually found incidentally at autopsy and on imaging. Most cases are isolated and small. Although they are not hormonally active, there is very rarely an association with functional adrenal disorders such as Cushing syndrome and congenital adrenal hyperplasia. It is believed that in these patients high corticotropin levels contribute to the pathogenesis of these neoplasms. We report the imaging appearances of bilateral giant adrenal myelolipomas in a patient known to have congenital adrenal hyperplasia. To our knowledge, these are the largest bilateral adrenal myelolipomas reported in association with congenital adrenal hyperplasia. A distinct change in their appearances after a period of steroid treatment is described for the first time.
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PMID:Bilateral giant adrenal myelolipomas. 1624 20

Primary aldosteronism, congenital adrenal hyperplasia, Cushing's syndrome, glucocorticoid-remediable aldosteronism, and corticotropin-dependent forms of adrenal pathology can cause hypertension by excessive production of adrenocortical hormones. Although traditional biochemical assays continue to be used, genetic testing has simplified the diagnosis of glucocorticoid-remediable aldosteronism. Also new interventional radiologic approaches for the diagnosis and treatment of corticotropin-dependent forms of Cushing's syndrome are available. Medical and surgical approaches, however, still remain viable options for treatment.
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PMID:Adrenocortical hypertension. 1512 76


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