1,721,061 research outputs found
Selenium and reproductive function. A systematic review
Full text linkSelenium (Se) is an essential element involved in normal gonadal development, gametogenesis, and fertilization. Molecular studies show that the gonads actively take up and store Se, most of which is incorporated in the glutathione peroxidase enzymes. We provide a systematic review of the original molecular studies, prospective observational data and randomized controlled trials on the role of Se in reproductive function conducted in the past 30 years. A critical appraisal of these findings suggests that Se supplementation produces a bell-shaped response curve, with negative effects observed for both low and high concentrations. The few available clinical trials support the use of Se supplementation (<200 μg/d) to improve male infertility, although their pre-treatment assessment of Se levels in enrolled subjects is inconsistent and their quality and size are insufficient to enable general recommendations. In females, a putative role in oocyte maturation and fertilization is suggested, but no large controlled trials have yet been performed. The role of Se supplementation on pregnancy outcomes is promising, and ongoing studies and meta-analysis should soon enable proper recommendations to be suggested. How best to assess Se in terms of cut-off value, sample type (serum, semen, other fluids) and the specific outcome of interest remains to be clarified. In the meantime, assessment of serum Se levels followed by low-dose replacement therapy when necessary is a reasonable approach to improve male idiopathic infertility and gestational outcome
Male hypogonadism
No full textThe hypothalamic-pituitary-gonadal (HPG) axis regulates the development, endocrine and reproductive function of the gonads throughout all phases of life. Male hypogonadism is defined an inadequate gonadal function, as manifested by deficiency in gametogenesis and/or secretion of gonadal hormones. In most cases, male hypogonadism is diagnosed through detailed history, physical examination and a few basic hormonal evaluations. In selected cases, however, additional tests are needed to define the aetiology and the extent of HPG axis dysfunction. These include semen analysis, pituitary imaging studies, genetic studies, bone densitometry, testicular ultrasonography, testicular biopsy and hormonal dynamic testing. The stimulation tests of the HPG are of particular importance in the differential diagnosis of congenital delayed puberty versus pre-pubertal hypogonadism in children. This review will focus on the methods, indications and limitations of endocrine testing in the characterisation and differential diagnosis of male hypogonadism at various ages. A practical hands-on guide on how to perform these tests is also provide
Phytotherapic approach in menopause: light and darkness
No full textMenopause is a critical period of the woman life, characterized by a peculiar modification in estrogens concentration and accompanied by different signs and symptoms. To prevent and contrast unfavorable consequences of menopause, different therapeutic approach could be evaluated. The hormone replacement therapy (HRT) is the most known, but it has several contraindications. The increasing interest in phytotherapy introduces the necessity for endocrinologist involved in menopause to suggest different therapeutic approach, considering the state of health of patient and the real efficacy of the drug. We aim to outline the main phytotherapy treatments to choose in menopause
Androgens, cardiovascular disease and osteoporosis.
No full textEpidemiological studies correlated the age-related decline of serum testosterone levels to the concomitant increase of cardiovascular diseases, osteoporosis and bone fractures. For this reason, testosterone replacement therapy (TRT) in older men with late-onset hypogonadism has been advocated. Testosterone has an anti-resorptive effect that may increase bone density at lumbar spine. Androgens may also have cardio-protective effects by improving endothelial function and reducing the risk factors for atherosclerosis. It has been proposed that atherosclerosis and osteoporosis share common pathophysiological mechanisms. The role of inflammatory cells, citokynes and calcium deposition into the vascular walls has been reviewed to explore the causal nexus between these frequently associated diseases. Experimental studies indicate that a deregulation in the commitment of pluripotent mesenchimal stem cells toward specialized phenotypes might participate in the development of these conditions. The crossed-over beneficial effect of bisphosphonate on the cardiovascular system and statins on bone metabolism supports the research for a unitary pharmacological approach to both conditions. The findings that androgens regulate mesenchimal cell differentiation, as well as body composition, lipid profile and bone metabolism, have claimed a role for TRT in aging men with late onset-hypogonadism
Management Strategies for Aggressive Cushing's Syndrome: From Macroadenomas to Ectopics.
Full text linkCushing's syndrome (CS) is a rare but severe clinical condition represented by an excessive endogenous cortisol secretion and hence excess circulating free cortisol, characterized by loss of the normal feedback regulation and circadian rhythm of the hypothalamic-pituitary axis due to inappropriate secretion of ACTH from a pituitary tumor (Cushing's disease, CD) or an ectopic source (ectopic ACTH secretion, EAS). The remaining causes (20) are ACTH independent. As soon as the diagnosis is established, the therapeutic goal is the removal of the tumor. Whenever surgery is not curative, management of patients with CS requires a major effort to control hypercortisolemia and associated symptoms. A multidisciplinary approach that includes endocrinologists, neurosurgeons, oncologists, and radiotherapists should be adopted. This paper will focus on traditional and novel medical therapy for aggressive ACTH-dependent CS. Several drugs are able to reduce cortisol levels. Their mechanism of action involves blocking adrenal steroidogenesis (ketoconazole, metyrapone, aminoglutethimide, mitotane, etomidate) or inhibiting the peripheral action of cortisol through blocking its receptors (mifepristone RU-486). Other drugs include centrally acting agents (dopamine agonists, somatostatin receptor agonists, retinoic acid, peroxisome proliferator-activated receptor γ PPAR-γ ligands) and novel chemotherapeutic agents (temozolomide and tyrosine kinase inhibitors) which have a significant activity against aggressive pituitary or ectopic tumors. © 2012 Carlotta Pozza et al
Subclinical male hypogonadism
No full textMale hypogonadism is traditionally defined as the inadequate production of testosterone and impaired spermatozoa generation in the presence of elevated or reduced levels of gonadotropins. A more frequent measurement of testosterone levels and the development of highly sensitive and specific assays have led to the detection of less clinically evident gonadal dysfunction, in which small biochemical alterations may or may not be accompanied by signs and symptoms. This condition is called "compensated" or "subclinical" hypogonadism. To determine whether subclinical hypogonadism is a paraphysiological state, a clinical condition in itself, or a precursor to overt hypogonadism, we carried out a literature review with the aim of establishing a practical approach to subclinical hypogonadism. (C) 2012 Elsevier Ltd. All rights reserved
Neuroendocrine Neoplasms with Peculiar Biology and Features. MEN1, MEN2A, MEN2B, MEN4, VHL, NF1
No full textA relevant number of neuroendocrine neoplasms (NENs) show a hereditary background being associated with a genetic endocrine neoplastic syndrome. Multiple endocrine neoplasia type 1 (MEN1), multiple endocrine neoplasia type 2 (MEN2), variants MEN2A and MEN2B, and multiple endocrine neoplasia type 4 (MEN4) present NENs as main and typical manifestations, while Von Hippel–Lindau disease (VHL) and neurofibromatosis type 1 (NF1) are mainly characterized by neoplasms of non-neuroendocrine origin.
Among NENs, pancreatic and thyroid tumors are most frequently associated with hereditary syndromes, the former being found in MEN1, MEN4, VHL, NF1, and the latter in MEN2A and B. Rare NEN sites are lung, thymus, and stomach, while pituitary and parathyroid adenomas are common in MEN1 and MEN4, as well as pheochromocytoma and paragangliomas in MEN2, VHL, NF1.
The diagnosis of hereditary NENs is anticipated of approximately two to three decades as compared to the sporadic counterpart. At histology the neuroendocrine tumors associated with genetic syndromes associated with hereditary syndromes are generally well differentiated, low proliferating, multiple, and multifocal. They are also frequently functioning, thus resulting in different types of endocrine syndromes, such as hyperinsulinemic hypoglycemia, Zollinger–Ellison, hyperprolactinemia, hyperparathyroidism, hypersecretion of catecholamines, and other rarer syndromes. Neuroendocrine carcinomas are extremely rare
The Woman's Heart: Insights into New Potential Targeted Therapy
No full textCardiovascular disease is an increasingly common cause of death in women. There is as yet no consensus on the analysis of cardiovascular risk factors with regard to the specific, personalised treatment of pre- and post-menopausal women. Clinically significant cardioprotective and antiremodelling effects have been observed in animal and human studies exploring chronic inhibition of phosphodiesterase type 5 (PDE5). The relationship between the heart, estrogens and PDE5 inhibitors (PDE5is) remains unclear. Experimental data suggest potential beneficial effects on cardiac geometry, function, endothelial function and microvascular coronary flow in women. It was recently postulated that the efficacy of PDE5is is estrogen-dependent in female heart disease. A registered randomised, placebo-controlled study, RECOGITO (NCT01803828), aimed at identifying the genderspecific efficacy of long-term PDE5 inhibition in diabetic cardiomyopathy, is currently recruiting patients. Estrogen receptor modulation could be a new promising approach to heart protection via PDE5is. PDE5is could be indicated as a gender-oriented strategy in modulated cardiac dysfunction and remodelling and in cardiac risk factors for selected cardiovascular diseases
Use of contrast enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) in the characterization of non-palpable testicular lesions
No full text- …
