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1.
BMC Surg ; 19(1): 146, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619236

RESUMO

BACKGROUND: Simulation in laparoscopic surgery is nowadays recognized as a valid instrument for learning and training surgeons in different procedures. However, its role as evaluation test and self-assessment tool to verify basic surgical skills is still under discussion. METHODS: Thirty-three residents in obstetrics and gynecology at University of Pisa, Italy were recruited, and they received a simulation program consisting of 5 tasks. They had to perform basic laparoscopic surgery maneuvers as creating pneumoperitoneum, positioning trocars under vision, demonstrating the appropriate use of dominant and non-dominant hand and making single stitch and knot. They were evaluated with a modified OSATs scale. RESULTS: Senior trainees had better score than junior trainees (p value< 0,005) and after different sessions of simulation scores of both groups significantly improved (p < 0,001), especially for the junior group. All the trainees reported self-assessments that matched with the evaluation of external observers demonstrating the importance of simulation also as auto-evaluation test. CONCLUSIONS: In this study, we demonstrated the role of simulation as powerful tool to evaluate and to self-assess surgical technical skills and to improve own capacities, with the use of a modified OSATs scale adapted to specific exercises.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/educação , Internato e Residência , Laparoscopia/educação , Treinamento por Simulação , Competência Clínica , Ginecologia/educação , Humanos , Itália , Cirurgiões/educação
2.
Maturitas ; 99: 1-9, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28364860

RESUMO

BACKGROUND: Estetrol (E4) is a natural estrogen produced solely during human pregnancy. E4 is suitable for clinical use since it acts as a selective estrogen receptor modulator. In clinical trials E4 has been seen to have little or no effect on coagulation. Hence, it is interesting to investigate whether E4 alters endothelial-dependent fibrinolysis. OBJECTIVES: We studied the effects of E4 on the fibrinolytic system and whether this could influence the ability of endothelial cells to migrate. In addition, we compared the effects of E4 with those of 17ß-estradiol (E2). STUDY DESIGN: Human umbilical vein endothelial cells (HUVEC) were obtained from healthy women. Expression of plasminogen-activator inhibitor-1 (PAI-1), urokinase-type plasminogen activator (u-PA) and tissue plasminogen activator (t-PA) proteins was evaluated by Western blot analysis. Endothelial cell migration was studied by razor-scrape horizontal and multiwell insert systems assays. RESULTS: E4 increased the expression of t-PA, u-PA and PAI-1 in HUVEC, but less so than did equimolar amounts of E2. The effects of E4 on t-PA, u-PA and PAI-1 were mediated by the induction of the early-immediate genes c-Jun and c-Fos. E4 in combination with E2 antagonized the effects induced by pregnancy-like E2 concentrations but did not impair the effects of postmenopausal-like E2 levels. We also found that the increased synthesis of PAI-1, u-PA and t-PA induced by E2 and E4 is important for horizontal and three-dimensional migration of HUVEC. CONCLUSIONS: These results support the hypothesis that E4 acts as an endogenous selective estrogen receptor modulator (SERM), controlling the fibrinolytic system and endothelial cell migration.


Assuntos
Movimento Celular/efeitos dos fármacos , Estetrol/farmacologia , Fibrinólise/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/efeitos dos fármacos , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Ativador de Plasminogênio Tecidual/efeitos dos fármacos , Ativador de Plasminogênio Tipo Uroquinase/efeitos dos fármacos , Western Blotting , Células Cultivadas , Células Endoteliais , Endotélio Vascular/efeitos dos fármacos , Estradiol/farmacologia , Estrogênios/farmacologia , Feminino , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
3.
J Neurochem ; 141(2): 165-178, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28072455

RESUMO

Schwann cells' (SCs) development and maturation require coordinate and complementary activation of several signals and intracellular pathways. Among factors controlling these processes, the signalling intermediates Src tyrosine kinase and focal adhesion kinase (FAK) are relevant for SCs', participating in regulation of their adhesion, motility and migration. Recently, the progesterone metabolite allopregnanolone (ALLO) was proved to be synthesized by SCs, whereas it acts autocrinally on SCs motility and proliferation, which are crucial processes for nerve development, maturation and regeneration. Herein, we investigate the hypothesis that the molecular mechanisms behind the ALLO's action on SCs involve the signalling intermediates Src and FAK. We first demonstrated that ALLO 10-6  M regulates SCs morphology, motility and myelination, also increasing the internode distance in the in vitro myelination model of neuron/SCs co-culture. ALLO's actions were mediated by the modulation of Src/FAK pathway, since they were counteracted by PP2 10-5  M, a selective inhibitor of Src kinase. Then, we proved that Src/FAK activation in SCs involves GABA-A dependent mechanisms and actin re-arrangements. In conclusion, our findings are the first to corroborate the importance of the neuroactive steroid ALLO in regulating SCs development and maturation via the Src and phospho-FAK signalling activation. Cover Image for this issue: doi: 10.1111/jnc.13795.


Assuntos
Movimento Celular/fisiologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Fibras Nervosas Mielinizadas/enzimologia , Pregnanolona/farmacologia , Células de Schwann/enzimologia , Quinases da Família src/metabolismo , Animais , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Ratos , Células de Schwann/efeitos dos fármacos
4.
Artigo em Inglês | MEDLINE | ID: mdl-27746764

RESUMO

The relationship between androgens and breast cancer is controversial. Androgens have complex effects on breast cancer progression and metastasis. Moreover, androgen receptor (AR) is expressed in approximately 70 to 90% of invasive breast carcinomas, which has prognostic relevance in basal-like cancers and in triple-negative breast cancers. Recent studies have associated the actin-binding proteins of the ezrin-radixin-moesin (ERM) family with metastasis in endocrine-sensitive cancers. We studied on T47D breast cancer cells whether androgens with different characteristics, such as testosterone (T), dihydrotestosterone (DHT), and dehydroepiandrosterone (DHEA) may regulate breast cancer cell motility and invasion through the control of actin remodeling. We demonstrate that androgens promote migration and invasion in T47D via Moesin activation. We show that T and DHEA exert their actions via the AR and estrogen receptor (ER), while the non-aromatizable androgen - DHT - only recruits AR. We further report that androgen induced significant changes in actin organization with pseudopodia along with membrane ruffles formation, and this process is mediated by Moesin. Our work identifies novel mechanisms of action of androgens on breast cancer cells. Through the modulation of Moesin, androgens alter the architecture of cytoskeleton in T47D breast cancer cell and promote cell migration and invasion. These results could help to understand the biological actions of androgens on breast cancer and, eventually, to develop new strategies for breast cancer treatment.

5.
Artigo em Inglês | MEDLINE | ID: mdl-26257704

RESUMO

Estetrol (E4) is a natural human estrogen that is present at high concentrations during pregnancy. E4 has been reported to act as an endogenous estrogen receptor modulator, exerting estrogenic actions on the endometrium or the central nervous system but presenting antagonistic effects on the breast. Due to these characteristics, E4 is currently being developed for a number of clinical applications, including contraception and menopausal hormone therapy. Endothelial nitric oxide (NO) is a key player for vascular function and disease during pregnancy and throughout aging in women. Endothelial NO is an established target of estrogens that enhance its formation in human endothelial cells. We here addressed the effects of E4 on the activity and expression of the endothelial nitric oxide synthase (eNOS) in cultured human umbilical vein endothelial cells (HUVEC). E4 stimulated the activation of eNOS and NO secretion in HUVEC. E4 was significantly less effective compared to E2, and a peculiar concentration-dependent effect was found, with higher amounts of E4 being less effective than lower concentrations. When E2 was combined with E4, an interesting pattern was noted. E4 antagonized NO synthesis induced by pregnancy-like E2 concentrations. However, E4 did not impede the modest induction of NO synthesis associated with postmenopausal-like E2 levels. These results support the hypothesis that E4 may be a regulator of NO synthesis in endothelial cells and raise questions on its peculiar signaling in this context. Our results may be useful to interpret the role of E4 during human pregnancy and possibly to help develop this interesting steroid for clinical use.

6.
Artigo em Inglês | MEDLINE | ID: mdl-26733941

RESUMO

The role of prolactin on breast cancer development and progression is debated. Breast cancer progression largely depends on cell movement and on the ability to remodel the actin cytoskeleton. In this process, actin-binding proteins are requested to achieve fibrillar actin de-polymerization and relocation at the cell membrane. Kinases such as focal adhesion kinase (FAK) are later required to form actin/vinculin-enriched structures called focal adhesion complexes, which mediate firm adhesion to the extracellular matrix. These controllers are regulated by c-Src, which forms multiprotein signaling complexes with membrane receptors and is regulated by a number of hormones, including -prolactin. We here show that breast cancer cells exposed to prolactin display an elevated c-Src expression and phosphorylation. In parallel, increased moesin and FAK expression and phosphorylation are found. These molecular changes are associated to relocation to the plasma membrane of cytoskeletal actin fibers and to increased horizontal cell movement. In conclusion, prolactin regulates actin remodeling and enhances breast cancer cell movement. This finding broadens the understanding of prolactin actions on breast cancer cells, highlighting new pathways that may be relevant to on breast cancer progression.

7.
Artigo em Inglês | MEDLINE | ID: mdl-24904530

RESUMO

Estetrol (E4) is a natural human estrogen present at high concentrations during pregnancy. Due to its high oral bioavailability and long plasma half-life, E4 is particularly suitable for therapeutic applications. E4 acts as a selective estrogen receptor (ER) modulator, exerting estrogenic actions on the endometrium or the central nervous system, while antagonizing the actions of estradiol in the breast. We tested the effects of E4 on its own or in the presence of 17ß-estradiol (E2) on T47-D ER+ breast cancer cell migration and invasion of three-dimensional matrices. E4 administration to T47-D cells weakly stimulated migration and invasion. However, E4 decreased the extent of movement and invasion induced by E2. Breast cancer cell movement requires a remodeling of the actin cytoskeleton. During exposure to E4, a weak, concentration-dependent, re-distribution of actin fibers toward the cell membrane was observed. However, when E4 was added to E2, an inhibition of actin remodeling induced by E2 was seen. Estrogens stimulate ER+ breast cancer cell movement through the ezrin-radixin-moesin family of actin regulatory proteins, inducing actin and cell membrane remodeling. E4 was a weak inducer of moesin phosphorylation on Thr(558), which accounts for its functional activation. In co-treatment with E2, E4 blocked the activation of this actin controller in a concentration-related fashion. These effects were obtained through recruitment of estrogen receptor-α. In conclusion, E4 acted as a weak estrogen on breast cancer cell cytoskeleton remodeling and movement. However, when E2 was present, E4 counteracted the stimulatory actions of E2. This contributes to the emerging hypothesis that E4 may be a naturally occurring ER modulator in the breast.

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