119 research outputs found
Moda e letteratura
No full textSi tratta di un contributo sul rapporto tra moda e letteratura a partire dall'Unità d'Italia, con particolare attenzione all'intreccio di letteratura e giornalismo, trasformazioni della femminilità da Verga e d'Annunzio a Pasolini e Arbasino
Aromatase activity and bone loss
No full textAromatase is a specific component of the cytochrome P450 enzyme system that is responsible for the transformation of 09 androgen precursors into C18 estrogenic compounds. This enzyme is encoded by the CYP19A1 gene located at chromosome 15q21.2, that is expressed in ovary and testis not only but also in many extraglandular sites such as the placenta, brain, adipose tissue, and bone. The regulation of the level and activity of aromatase determines the levels of estrogens that have endocrine, paracrine, and autocrine effects on target issues including bone. Importantly, extraglandular aromatization of circulating androgen precursors is the major source of estrogen not only in men (since only 15% of circulating estradiol is released directly by the testis) but also in women after the menopause. Several lines of clinical and experimental evidence now clearly indicate that aromatase activity and estrogen production are necessary for longitudinal bone growth, attainment of peak bone mass, the pubertal growth spurt, epiphyseal closure, and normal bone remodeling in young individuals. Moreover, with aging, individual differences in aromatase activity and thus in estrogen levels may significantly affect bone loss and fracture risk in both genders
Vitamin D deficiency and primary hyperparathyroidism
No full textVitamin D via its receptor has essential actions on parathyroid cells, inhibiting PTH secretion, and parathyroid cell proliferation. While the effects of vitamin D depletion in the pathogenesis of secondary hyperparathyroidism in elderly individuals or in the occurrence of parathyroid hyperplasia in patients with renal insufficiency are well established, the association between hypovitaminosis D and primary hyperparathyroidism (P-HPT) has only recently become appreciated. In different cohorts of patients with P-HPT, vitamin D deficiency has been recently associated with higher PTH levels, larger adenomas, and a more severe
phenotype (including osteitis fibrosa cystica) as well as negative post-operative outcomes following parathyroidectomy. Despite current guidelines recommend measurement of serum 25OHD (25-hydroxy-cholecalciferol) in P-HPT and their repletion if the levels are <20 ng/ml, future well-designed trials of vitamin D supplementation in P-HPT patients with coexisting vitamin D deficiency are needed to evaluate the risk/benefit profile of this treatment
Lasofoxifene: a new-generation SERM for the treatment of postmenopausal osteoporosis
No full textLasofoxifene is a new-generation selective estrogen receptor modulator that completed the Phase III development program for the prevention and treatment of osteoporosis in postmenopausal women. This compound has a remarkably improved oral bioavailability with respect to other selective estrogen receptor modulators owing to its increased resistance to intestinal wall glucuronidation. In both preclinical and short-term Phase II clinical studies, lasofoxifene showed a favorable safety profile and demonstrated a proven efficacy in preventing bone loss and lowering cholesterol levels. The recent results from Phase III clinical trials demonstrated the clinical efficacy of this drug in the prevention of vertebral and nonvertebral fractures. The purpose of this article is to review the clinical evidence for the use of lasofoxifene in women after menopause and to discuss how it will fit into the treatment of postmenopausal osteoporosis. © 2009, Expert Reviews Ltd. All rights reserved
MicroRNAs in bone diseases
No full textMicroRNAs are small, noncoding single-stranded RNAs that have emerged as important posttranscriptional regulators of gene expression, with an essential role in vertebrate development and different biological processes. This review highlights the recent advances in the function of miRNAs and their roles in bone remodeling and bone diseases. MicroRNAs (miRNAs) are a class of small (∼22 nt), noncoding single-stranded RNAs that have emerged as important post transcriptional regulators of gene expression. They are essential for vertebrate development and play critical roles in different biological processes related to cell differentiation, activity, metabolism, and apoptosis. A rising number of experimental reports now indicate that miRNAs contribute to every step of osteogenesis and bone homeostasis, from embryonic skeletal development to
maintenance of adult bone tissue, by regulating the growth, differentiation, and activity of different cell systems inside and outside the skeleton. Importantly, emerging information from animal studies suggests that targeting miRNAs might become an attractive and new therapeutic approach for osteoporosis or other skeletal diseases, even though there are still major concerns related to potential off target effects and the need of efficient delivery methods in vivo. Moreover, besides their recognized effects at the cellular level, evidence is
also gathering that miRNAs are excreted and can circulate in the blood or other body fluids with potential paracrine or endocrine functions. Thus, they could represent suitable candidates for becoming sensitive disease biomarkers in different pathologic conditions, including skeletal disorders. Despite these
promising perspectives more work remains to be done until miRNAs can serve as robust therapeutic targets or established diagnostic tools for precision medicine in skeletal disorders
Vescicole extracellulari e metabolismo osseo: ruolo e possibili implicazioni cliniche
No full textLe vescicole extracellulari (EV) sono secrete da vari tipi cellulari e veicolano cargo specifici destinati alle cellule target, mediando così effetti paracrini in meccanismi fisiologici e patologici. Negli ultimi anni lo studio delle EV si è affermato in moltissimi ambiti, compreso il mondo del metabolismo osseo. In questa rassegna riportiamo i più recenti e promettenti studi sul ruolo biologico delle EV nel tessuto osseo e il loro potenziale utilizzo in strategie terapeutiche
Aromatase Activity and Bone Loss in Men
No full textAromatase is a specific component of the cytochrome P450 enzyme system responsible for the transformation of androgen precursors into estrogens. This enzyme is encoded by the CYP19A1 gene located at chromosome 15q21.2, that is, expressed in ovary and testis, but also in many extraglandular sites such as the placenta, brain, adipose tissue, and bone. The activity of aromatase regulates the concentrations of estrogens with endocrine, paracrine, and autocrine effects on target issues including bone. Importantly, extraglandular aromatization of circulating androgen precursors is the major source of estrogen in men. Clinical and experimental evidences clearly indicate that aromatase activity and estrogen production are necessary for longitudinal bone growth, the attainment of peak bone mass, pubertal growth spurt, epiphyseal closure, and normal bone remodeling in young individuals. Moreover, with aging, individual differences in aromatase activity may significantly affect bone loss and fracture risk in men
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