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Abstract

Wharton’s Jelly (WJ) tissue is a promising biomaterial, for tissue engineering applications. However, its preservation over a long period in order to be readily available needs further optimization. A possible solution could be the vitrification and storage of WJ tissue at low temperatures. The aim of this study is to evaluate the effect of low temperature in the WJ tissue, which was stored at ?196?°C, either with the vitrification or conventional cryopreservation methods. WJ tissues were isolated from human umbilical cords, cryopreserved with the above methods and remained for 1?year at ?196?°C. Histological analysis of tissue’s extracellular matrix (ECM), isolation, and characterization of mesenchymal stromal cells (MSCs) were performed. Histological analysis revealed the presence of ECM components such as collagen, sulfated glycosaminoglycans (sGAGs), and the presence of cell nuclei only in vitrified samples. Furthermore, MSCs were isolated and expanded successfully from vitrified WJ tissues, whereas a few viable cells were obtained from conventionally cryopreserved tissues that were not further expanded. In conclusion, this study indicated the proper preservation of vitrified WJ tissues after 1?year of storage, which eventually could be used in tissue engineering and regenerative medicine approaches.  相似文献   
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BACKGROUND Coronavirus disease 2019(COVID-19) significantly affected endoscopy practice,as gastrointestinal endoscopy is considered a risky procedure for transmission of infection to patients and personnel of endoscopy units(PEU).AIM To assess the impact of COVID-19 on endoscopy during the first European lockdown(March-May 2020).METHODS Patients undergoing endoscopy in nine endoscopy units across six European countries during the period of the first European lockdown for COVID-19(MarchMay 2020) were included. Prior to the endoscopy procedure, participants were stratified as low-or high-risk for potential COVID-19 infection according to the European Society of Gastrointestinal Endoscopy(ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates(ESGENA) joint statement, and contacted 7-14 d later to assess COVID-19 infection status. PEU were questioned regarding COVID-19 symptoms and/or infection via questionnaire, while information regarding hospitalizations, intensive care unitadmissions and COVID-19-related deaths were collected. The number of weekly endoscopies at each center during the lockdown period was also recorded.RESULTS A total of 1267 endoscopies were performed in 1222 individuals across nine European endoscopy departments in six countries. Eighty-seven(7%) were excluded because of initial positive testing. Of the 1135 pre-endoscopy low risk or polymerase chain reaction negative for COVID-19, 254(22.4%) were tested post endoscopy and 8 were eventually found positive, resulting in an infection rate of 0.7% [(95%CI: 0.2-0.12]. The majority(6 of the 8 patients, 75%) had undergone esophagogastroduodenoscopy. Of the 163 PEU, 5 [3%;(95%CI: 0.4-5.7)] tested positive during the study period. A decrease of 68.7%(95%CI: 64.8-72.7) in the number of weekly endoscopies was recorded in all centers after March 2020. All centers implemented appropriate personal protective measures(PPM) from the initial phases of the lockdown.CONCLUSION COVID-19 transmission in endoscopy units is highly unlikely in a lockdown setting, provided endoscopies are restricted to emergency cases and PPM are implemented.  相似文献   
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Kikuchi-Fujimoto disease (KFD) is a benign and self-limited disease of unknown etiology that affects mainly young women. It presents with localized lymphadenopathy, usually cervical, accompanied with fever, night sweats, and leucopenia. KFD has been rarely described in association with autoimmune disorders, mainly systemic lupus erythematosus (SLE). We report the case of a young patient presenting with KFD coinciding with SLE. The association of KFD and SLE is reviewed. Moreover, a possible pathogenetic role of Ebstein-Barr virus linking the two clinical entities is discussed.  相似文献   
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Archives of Women's Mental Health - Limited research exists on suicidal behaviors among women with disabilities. This study examined disability, suicidal behaviors, and associated health...  相似文献   
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This is the first part of a 3‐part comprehensive review of intraosseous carcinoma of the jaws. We have outlined 4 groups of intraosseous carcinoma of the jaws (metastatic, salivary‐type, odontogenic, and primary intraosseous carcinoma), emphasizing the need for accurate diagnosis and the problems associated with changing classification systems, standardization of diagnostic criteria and nomenclature, and the accuracy of existing literature. In this first part, the features of metastatic and the very rare salivary‐type carcinomas of the jaws are examined with particular emphasis on histologic and immunohistochemical characteristics, diagnostic difficulties, and uncertainties. © 2012 Wiley Periodicals, Inc. Head Neck, 2012  相似文献   
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