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Controlled ovarian stimulation (COH) in PCOS is a challenge for fertility expert both ovarian hyperstimulation syndrome (OHSS) and oocytes immaturity are the two major complication. Ovarian response to COH vary widely among POCS patients and while some patients are more likely to show resistance to COH, other experienced an exaggerated response. The aim of our study is to investigate a possible correlation between PCOS phenotypes and the variety of ovarian response to COH and ART outcomes in patients with different PCOS phenotypes. We retrospectively analyzed a total of 71 cycles performed in 44 PCOS infertile patients attending ART at Centre of Infertility and Assisted Reproduction of Pisa University between January 2013 and January 2016. Patientsundergoing IVF with GnRH-antagonist protocol and 150–225?UI/days of recombinant FSH; triggering was carried out using 250 mg of recombinant hCG or a GnRH analogous on the basis of the risk to OHSS. We observed that Phenotype B had a tendency to have a greater doses of gonadotropins used respect to all phenotypes. Phenotype A group showed a greater serum estrogen levels compared to all phenotypes groups, a greater number of follicles of diameter between 8–12?mm found by ultrasound on the day of triggering and a greater mean number of freeze embryo. Additionally serum AMH and antral follicles count (AFC) follow the same trend in the different phenotypes ad they were significantly higher in phenotype A and in phenotype D. In conclusion this study shows that the features of PCOS phenotypes reflect the variety of ovarian response to COH as well as the risks to develop OHSS. Serum AMH and AFC are related to the degree of ovulatory dysfunction making these ‘added values’ in identifying the different PCOS phenotypes. Phenotype A seems to be the phenotype with the higher risk to develop OHSS and the use of GnRH as a trigger seems to improve oocyte quality. To classify PCOS phenotype at diagnosis might help clinicians to identify patients at greater risk of OHSS, customize therapy and subsequently plan the trigger agent.  相似文献   
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We examined the autocrine/paracrine role of interleukin-8 (CXCL8) and the functional significance of CXCL8 receptors, CXCR1 and CXCR2, in human malignant melanoma proliferation, migration, invasion and angiogenesis. We found that a panel of seven cell lines, even though at different extent, secreted CXCL8 protein, and expressed CXCR1 and CXCR2 independently from the CXCL8 expression, but depending on the oxygen level. In fact, hypoxic exposure increases the expression of CXCR1 and CXCR2. The cell proliferation of both M20 and A375SM lines, expressing similar levels of both CXCR1 and CXCR2 but secreting low and high amounts of CXCL8, respectively, was significantly enhanced by CXCL8 exposure and reduced by CXCL8, CXCR1 and CXCR2 neutralising antibodies, indicating the autocrine/paracrine role of CXCL8 in melanoma cell proliferation. Moreover, an increased invasion and migration in response to CXCL8 was observed in several cell lines, and a further enhancement evidenced under hypoxic conditions. A CXCL8-dependent in vivo vessel formation, evaluated through a matrigel assay, was also demonstrated. Furthermore, when neutralising antibodies against CXCR1 or CXCR2 were used, only the involvement of CXCR2, but not CXCR1 was observed on cell migration and invasion, while both receptors played a role in angiogenesis.In summary, our data demonstrate that CXCL8 induces cell proliferation and angiogenesis through both receptors and that CXCR2 plays an important role in regulating the CXCL8-mediated invasive and migratory behaviour of human melanoma cells. Thus, blocking the CXCL8 signalling axis promises an improvement for the therapy of cancer and, in particular, of metastatic melanoma.  相似文献   
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Colon tumors may be maintained by a rare fraction of cancer stem-like cells (CSC) that express the cell surface marker CD133. Self-renewing CSCs exhibit relatively greater resistance to clinical cytotoxic therapies and recent work suggests that this resistance may be mediated in part by an autocrine response to the immune cytokine interleukin 4 (IL-4). Blocking IL-4 signaling can sensitize CSCs to apoptotic stimuli and increase the in vivo efficacy of cytotoxic therapy. These findings suggest that inhibitors of IL-4 signaling may offer a new therapeutic tool in colon carcinoma.  相似文献   
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Objective: The objective of this study was to assess left ventricle (LV) function and remodeling by three-dimensional echocardiography (3DE) in patients who underwent arterial switch procedure (ASO) for transposition of great arteries (TGA) in long-term follow-up. Methods and Results: We studied 54 asymptomatic patients (39 male) who have undergone single-stage ASO for TGA, aged 13.7 ± 4.7 years, with a normal LV ejection fraction (EF), compared to healthy peers. We evaluated LV volume and function in asymptomatic patients with normal ejection fraction by 3DE. All patients had normal EF, measured by modified Simpson’s method (mean 60.9 ± 3.5%) and by 3D method (mean 62.3 ± 3.8%). No statistically significant differences were documented between 2D and 3D measures of age-related LV volumes. Comparison of 3D volumes with reference ones was performed only in pediatric patients (<18 years old). In this subgroup (n = 42) 3D volumes were significantly higher than reference values from the age of 9 years (End-diastolic volume: 9–12 years 79.61 ± 20.29 ml vs. 53.52 ± 13.94 ml, p < 0.001; 13–17 years 107.30 ± 23.28 ml vs. 81.78 ± 26.44 ml, p = 0.0038). Conclusions: Children and young adults late after ASO demonstrate normal ejection fraction, but present subclinical signs of ventricular and myocardial remodeling, such as increased LV dimensions, when using 3D echocardiography. Our findings support the usefulness of 3DE to detect LV remodeling precociously.  相似文献   
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Galápagos tortoises represent the only surviving lineage of giant tortoises that exhibit two different types of shell morphology. The taxonomy of Galápagos tortoises was initially based mainly on diagnostic morphological characters of the shell, but has been clarified by molecular studies indicating that most islands harbor monophyletic lineages, with the exception of Isabela and Santa Cruz. On Santa Cruz there is strong genetic differentiation between the two tortoise populations (Cerro Fatal and La Reserva) exhibiting domed shell morphology. Here we integrate nuclear microsatellite and mitochondrial data with statistical analyses of shell shape morphology to evaluate whether the genetic distinction and variability of the two domed tortoise populations is paralleled by differences in shell shape. Based on our results, morphometric analyses support the genetic distinction of the two populations and also reveal that the level of genetic variation is associated with morphological shell shape variation in both populations. The Cerro Fatal population possesses lower levels of morphological and genetic variation compared to the La Reserva population. Because the turtle shell is a complex heritable trait, our results suggest that, for the Cerro Fatal population, non-neutral loci have probably experienced a parallel decrease in variability as that observed for the genetic data.  相似文献   
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