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The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues.  相似文献   
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It is agreed that ovarian stimulation results in histopathologic changes and variations in gene expression when compared to natural cycles. However, the enigma is still present: What is the true impact of variable degrees of embryo-endometrium developmental asynchrony in the presence of high clinical embryo implantation rates in IVF? It is postulated that the temporal characterization of gene expression and protein profiles of isolated endometrial compartments might unveil patterns that are critical for the establishment of the window of implantation.  相似文献   
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Purpose: To investigate the effect of the cumulative exposure to estradiol (E2) during the follicular phase on IVF outcome. Methods: Patients were stimulated with recombinant FSH after GnRH agonist suppression and had a day 3-embryo transfer. Estrogen exposure was determined as the area under the curve (AUC) for serum E2 levels measured from the first day of stimulation through the day after hCG administration. Results: E2 AUC thresholds for 10th and 90th percentiles were 4704 pg/ml and 16338 pg/ml, respectively. The pregnancy and implantation rates were highest in the 10th–90th percentile group, and were statistically higher in this group than in the >90th percentile group (54.6% vs. 33.3% and 24.8% and 12.9%, respectively, for pregnancy and implantation rates, P < 0.05). Recovered mature oocytes, fertilization, and number and mean score of transferred embryos were similar. Conclusions: High cumulative E2 exposure during the follicular phase of IVF cycles has detrimental effects on implantation.  相似文献   
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Laparoscopic techniques have revolutionized the concept of minimally invasive surgery. Robotically assisted surgery is one of the latest innovations in this field and many operative laparoscopic procedures have been performed in urology, cardiac and general surgery. More recently, the use of robotically assisted techniques have been introduced in gynaecology, and most available studies have shown it to be a safe and effective alternative to conventional laparoscopic surgery. However, whether or not to approach the management of certain gynaecological pathologies with a laparotomy or laparoscopy (conventional or with robotic aid) continues to be a point of debate. This article reviews recent developments in the endoscopic management of reproductive (tubal reanastomosis and myomectomies) and other gynaecological surgical conditions (hysterectomies, pelvic organ prolapse, repair of vesicovaginal fistulas and staging for gynaecological malignancies). Ongoing controversies associated with this technology, such as cost, learning curve, conversion rate to laparotomy, post-surgical fertility and complications, are briefly addressed. Long-term analysis of outcomes is ongoing.  相似文献   
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Background Biliary tract cancers (BTC) are rare but highly aggressive tumours with poor prognosis, usually detected at advanced stages. Herein, we aimed at identifying BTC-specific DNA methylation alterations.Methods Study design included statistical power and sample size estimation. A genome-wide methylation study of an explorative cohort (50 BTC and ten matched non-tumoral tissue samples) has been performed. BTC-specific altered CpG islands were validated in over 180 samples (174 BTCs and 13 non-tumoral controls). The final biomarkers, selected by a machine-learning approach, were validated in independent tissue (18 BTCs, 14 matched non-tumoral samples) and bile (24 BTCs, five non-tumoral samples) replication series, using droplet digital PCR.Results We identified and successfully validated BTC-specific DNA methylation alterations in over 200 BTC samples. The two-biomarker panel, selected by an in-house algorithm, showed an AUC > 0.97. The best-performing biomarker (chr2:176993479-176995557), associated with HOXD8, a pivotal gene in cancer-related pathways, achieved 100% sensitivity and specificity in a new series of tissue and bile samples.Conclusions We identified a novel fully efficient BTC biomarker, associated with HOXD8 gene, detectable both in tissue and bile by a standardised assay ready-to-use in clinical trials also including samples from non-invasive matrices.Subject terms: Diagnostic markers, Biliary tract cancer  相似文献   
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Endometriosis-associated ovarian cancer represents the most common form of malignancy associated with this benign disease. It has a better prognosis than most types of ovarian cancer, with endometrioid adenocarcinoma and clear cell carcinoma as the main histological types. Clinical presentation is usually nonspecific and tumor biomarkers can be misleading, since they can also be elevated in the presence of benign ovarian endometriosis. We report a case of a 52-year-old woman with known ovarian and deep pelvic endometriosis, who developed ovarian clear cell carcinoma within a large endometrioma. The imaging findings highlight the key role of magnetic resonance imaging in detecting suspicious features such as loss of the “T2 shading” sign, loss of high T1 signal of an endometrioma, or the presence of mural nodules. Early detection of these malignancies is fundamental for adequate surgical treatment and overall outcome.  相似文献   
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