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51.
环境内分泌干扰物(EED)广泛存在于日常生活中,是一类可以干扰激素行为的外源性化学物。EED可以结合人体内不同的受体,通过多种机制增强或抑制体内正常的内分泌功能,从而引发多种疾病。多囊卵巢综合征(PCOS)病因复杂,已有研究结果表明PCOS的发生与环境因素有关。相关流行病学和基础实验研究表明,EED参与PCOS的发生、发展,但具体作用机制仍需进一步研究。现就EED与PCOS的关系及可能的相关作用机制进行阐述,总结EED与PCOS的关系,为干预PCOS患者的生活方式并阻断疾病发生提供新的线索。  相似文献   
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Primary hyperparathyroidism is a common endocrine disorder and the most prevalent cause of hypercalcemia worldwide. While most cases are sporadic, 5–10% of cases are inherited as part of a familial syndrome: multiple endocrine neoplasia (MEN-1, MEN-2A, MEN-4), hyperparathyroidism jaw-tumor syndrome (HPT-JT), familial hypocalciuric hypercalcemia (FHH), neonatal severe hyperparathyroidism (NSHPT), autosomal dominant moderate hyperparathyroidism (ADMH), or familial isolated hyperparathyroidism (FIHPT). Recent developments in molecular pathology identified specific germline mutations (MEN1, RET, CDKIs, CDC73/HRPT2, CaSR, GNA11, AP2S1) implicated in their pathogenesis. In contrast to sporadic primary hyperparathyroidism which is usually caused by a solitary parathyroid adenoma, hereditary hyperparathyroidism tend to present with multiglandular parathyroid disease, with variable penetrance according to the genetic syndrome. As a result, the clinical severity of each familial condition varies tremendously, resulting in distinct prognosis and treatment strategies. With the advent of molecular testing, genetic subtyping has become an integral part of treatment decision making, requiring correlation with clinical and pathologic findings. This review provides an update on the current knowledge of hereditary hyperparathyroidism and its associated genetic syndromes.  相似文献   
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Dioxins and dioxin-like compounds (DLCs) are the ones with poor water solubility and low volatility, resistant to physical, chemical and biological processes, persistent in the environment even under extreme conditions. Due to lipophilic nature, they get adhered to the fatty material and concentrate through biomagnification and bioaccumulation, thereby easily getting incorporated into food chains, paving the way to endocrine disruption via modulation of various human receptors. This in turn leads to certain adverse health effects. In the present study, a total of 100 dioxins and DLCs were taken and their binding pattern was assessed with the ketosteroid receptors, i.e. androgen (hAR), glucocorticoid (hGR), progesterone (hPR) and mineralocorticoid (hMR) in comparison to the corresponding natural steroids and a known endocrine disrupting xenobiotic, Bisphenol A (BPA). Most of the DLCs, particularly those bearing hydroxyl (-OH) group showed considerable affinities with ketosteroid receptors. On comparing D scores of all the dioxins and DLCs against all four receptors, compound 8-hydroxy-3,4-dichlorodibenzofuran(8-OH-DCDF) exhibited least D score of -9.549?kcal mol?1 against hAR. 3,8-Dihydroxy-2-chlorodibenzofuran(3,8-DiOH-CDF), 4′-hydroxy-2,3,4,5-tetrachlorobiphenyl (4′-OH-TCB) and 4-hydroxy-2,2′,5′-trichlorobiphenyl(4-OH-TCB) also showed comparable molecular interactions with the ketosteroid receptors. These interactions mainly include H-bonding, π–π stacking, hydrophobic, polar and van der Waals’ interactions. In contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, i.e. certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.  相似文献   
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Multiple endocrine neoplasia type 2A (MEN 2A) is an autosomal dominant inherited condition with a prevalence of one in 40?000 individuals. It causes the development of tumours in endocrine glands, such as medullary thyroid cancer, pheochromocytomas, as well as primary hyperparathyroidism. MEN 2A in pregnancy is very rare with only 29 cases reported in the literature. The presence of pheochromocytoma is a rare cause of hypertension during pregnancy with an incidence of 0.007% of all pregnancies. This has severe implications on both mother and the foetus. This case report describes a 22-year-old nulliparous Caucasian woman with known MEN2A syndrome, who underwent thyroidectomy for medullary thyroid carcinoma in childhood and excision of left sided pheochromocytoma at the age of 19. She was found to have a recurrence of pheochromocytoma in the right adrenal gland during pregnancy at 16 weeks of gestation and was oddly normotensive. Catecholamine effects were blocked with phenoxybenzamine and she delivered by an uneventful elective caesarean section at 36 weeks gestation. She underwent a laparoscopic right adrenalectomy six weeks postpartum, followed by lifelong corticosteroid replacement.  相似文献   
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Plasma transthyretin (TTR) is a plasma protein secreted by the liver that circulates bound to retinol-binding protein 4 (RBP4) and its retinol ligand. TTR is the sole plasma protein that reveals from birth to old age evolutionary patterns that are closely superimposable to those of lean body mass (LBM) and thus works as the best surrogate analyte of LBM. Any alteration in energy-to-protein balance impairs the accretion of LBM reserves and causes early depression of TTR production. In acute inflammatory states, cytokines induce urinary leakage of nitrogenous catabolites, deplete LBM stores, and cause an abrupt decrease in TTR and RBP4 concentrations. As a result, thyroxine and retinol ligands are released in free form, creating a second frontline that strengthens that primarily initiated by cytokines. Malnutrition and inflammation thus keep in check TTR and RBP4 secretion by using distinct and unrelated physiologic pathways, but they operate in concert to downregulate LBM stores. The biomarker complex integrates these opposite mechanisms at any time and thereby constitutes an ideally suited tool to determine residual LBM resources still available for metabolic responses, hence predicting outcomes of the most interwoven disease conditions.  相似文献   
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