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Reactive Oxygen Species (ROS) are produced during oxidative metabolism, and regulate many biological processes. The acute inflammation characterizing parturition induces many physiological changes. Among them, there is evidence that ROS affect the synthesis of many factors involved in parturition. Our study aims to determine serum levels of ROS in periparturient ewes, as well as to establish a value of reference of their physiological concentration.

ROS determination was performed on blood collected every 12 hours in periparturient twin pregnant ewes. Our results will show a significant increase in ROS concentrations from the beginning to the end of the experiment. This increase may be due to the inflammatory process establishing during parturition.  相似文献   
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Ductal carcinoma in situ (DCIS) is a heterogeneous disease that has been investigated less extensively than invasive breast cancer. Women with DCIS are mainly treated with conservative surgery almost exclusively followed by radiotherapy. However, as radiation treatment is not always effective, the search for biomarkers capable of identifying DCIS lesions that could progress to invasive cancer is ongoing. Although conventional biomarkers have been thoroughly studied in invasive tumours, little is known about the role played by androgen receptor (AR), widely expressed in DCIS. A series of 42 DCIS patients treated with quadrantectomy and radiotherapy were followed for a period of up to 95 months. Of these, 11 had recurrent DCIS or progressed to invasive cancer. All tumours were analysed for clinical pathological features. Conventional biomarkers and androgen receptor expression were determined by immunohistochemistry. Our results showed that AR was higher in tumours of relapsed patients than non‐relapsed patients (P value: 0.0005). Conversely, oestrogen receptor (ER) was higher, albeit not significantly, in non‐relapsed patients than in relapsed patients. AR/ER ratio was considerably different in the two subgroups (P value: 0.0033). Area under the curve (AUC) values were 0.85 for AR and 0.80 for the AR/ER ratio. These preliminary results highlight the potentially important role of both AR and the AR/ER ratio as prognostic markers in DCIS.  相似文献   
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The prevalence of people who are overweight or obese has increased dramatically in high-income countries over the past 20 years. There is a strong association between obesity and infertility, and weight loss can result in increased fecundity in obese women. The aim of this study is to demonstrate the potential role of intragastric balloon in the treatment of obese-related infertility. This is a retrospective study. A chart review of 27 obese women seen between September 2003 and July 2008 was performed. They all presented with the diagnosis of infertility and had undergone endoscopic intragastric balloon positioning. Among these women who tried unsuccessfully to become pregnant before weight loss, 15 became pregnant afterward. The pregnancies proceeded without complications and ended with live births. An improvement in the fertility status after weight loss has been described, although data on fertility after weight loss following bariatric surgery are still limited. The results obtained in our experience are not different from data reported in literature for bariatric surgery. Therefore, balloon treatment might be effective in young infertile obese women who wish to become pregnant.  相似文献   
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Objectives: Blood flow to the fetal brain is supplied by two vascular systems: the vertebral artery (VA) and the internal carotid artery with its anatomical continuation, the middle cerebral artery (ICA/MCA). In this work, our aim was to establish consistent reference values for the comparative study of both arterial systems.

Methods: The study group consisted of 2323 Doppler examinations of the VA, MCA and UA performed on 2323 single pregnancies between 19 and 41 weeks. These values were afterwards used to calculate the pulsatility index (PI), peak systolic velocity (PSV) and cerebro-placental ratio (CPR) percentiles.

Results: The VA and MCA PI reached maximum values at the end of the second trimester and decreased afterwards due to an increase in the diastolic flow. Conversely, the VA and MCA PSV increased progressively until the end of pregnancy. Regarding the VA and MCA CPR values, they were higher in the middle of the third trimester and decreased afterwards.

Conclusions: In both arterial systems, Doppler reference values have been calculated for the PI, PSV and CPR, being available for future comparative studies.  相似文献   

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Chronic skin ulcers, consequence of diabetes and other pathological conditions, heavily compromise the patient life quality and represent a high and constantly growing cost for National Health Services. Autologous platelet‐rich plasma (PRP), has been proposed to treat these lesions. The absence of guidelines for the PRP production and the need of a fresh preparation for each treatment lead us to develop a protocol for the production of an allogenic PRP‐based bioactive membrane (BAM), standardized for platelet concentration and growth factor release. This work compares BAMs obtained starting from two different platelet concentrations. There was no direct correlation between the amount of growth factors released by BAM in vitro and the initial platelet count. However, different release kinetics were noticed for different growth factors, suggesting that they were differently retained by the two BAMs. The angiogenic potential of both BAMs was determined by Luminex Angiogenesis Assay. The biological activity of the factors released by the two BAMs was confirmed by cell proliferation and migration. A diabetic mouse chronic ulcer model was used to define the best PRP therapeutic dose in vivo. Both BAMs induced wound healing by increasing the thickness of the regenerated epidermis and the vessel number. However, a too high platelet concentration resulted in a slowdown of the membrane resorption that interfered with the skin healing. Overall, the results indicate that the BAMs could represent a natural and effective wound healing tool for the treatment of skin ulcers. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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