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991.
FGF-2, a potent angiogenic factor that is involved in tumor invasion, is known to be released extracellularly by a nonclassical secretory pathway. Recently it has become clear that Epstein-Barr virus, specifically its oncoprotein LMP1, can induce expression of angiogenic factors. Among these factors is FGF-2. LMP1 not only promotes expression of FGF-2, but also the release extracellularly of its 18-kDa isoform. We analyzed the mechanism of FGF-2 release induced by LMP1. Confocal immunofluorescence microscopy revealed colocalization of FGF-2 with LMP1 in small dots also stained positively for CD63 and cathepsin D, markers of late endosomes or multivesicular bodies. Biochemical analysis and immunoelectron microscopy of purified exosomal fractions from cotransfected cells demonstrated increased release of exosomes and the concentration of LMP1 and FGF-2 in these structures. Moreover, cotransfection appeared to induce partial redistribution of the Na(+)/K(+)-ATPase, which participates in FGF-2 release, from the plasma membrane to the intracellular LMP1/FGF-2 positive dots. Treatment with ouabain, which inhibits Na(+)/K(+)-ATPase activity, partially suppressed FGF-2 secretion via exosomes in a dose-dependent manner. The results suggest that exosomes may represent a previously unrecognized mechanism for FGF-2 release mediated by LMP1, and that this pathway involves the activity of Na(+)/K(+)-ATPase.  相似文献   
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Interferon alpha (IFNalpha) induces an EGF-Ras-->Raf-1-->Erk dependent survival pathway counteracting apoptosis induced by the cytokine. In this paper we have evaluated the effects of the combination between farnesyl-transferase inhibitor (FTI) R115777 and IFNalpha on the growth inhibition and apoptosis of cancer cells. Simultaneous exposure to R115777 and IFNalpha produced synergistic both antiproliferative and proapoptotic effects. In these experimental conditions, IFNalpha and R115777 completely antagonized the increased activity of both Ras and Erk-1/2 induced by IFNalpha and strongly reduced Akt activity. Furthermore, treatment with R115777 in combination with IFNalpha regimen induced tumor growth delay on established KB cell xenografts in nude mice, while the single agents were almost inactive. R115777 was again able to antagonize the Ras-dependent survival pathway induced by IFNalpha also in vivo. Raf-1, one of the downstream targets of Ras, has been reported to activate bcl-2 through displacement and/or phosphorylation of Bad. We have found that IFNalpha induced mitochondrial localization of Raf-1 that was antagonized by R115777. Moreover, IFNalpha increased Raf-1/bcl-2 immuno-conjugate formation and intracellular co-localization and enhanced phosphorylation of Bad at Ser 112 and again R115777 counteracted all these effects. Moreover, the use of plasmids encoding for dominant negative or dominant positive Raf-1 antagonized and potentiated, respectively, the co-immunoprecipitation between Raf-1 and bcl-2. In conclusion, FTI R115777 strongly potentiates the antitumor activity of IFNalpha both in vitro and in vivo through the inhibition of different survival pathways that are dependent from isoprenylation of intracellular proteins such as ras.  相似文献   
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IntroductionHealthy sexual function during pregnancy and after childbirth is one of the cornerstones for couples to evolve from partners to parents.AimThe aim of our review is to evaluate the available evidence and define present knowledge about female sexual function during pregnancy and after childbirth.MethodsPubMed was searched for articles on sexual function during pregnancy and after childbirth, published from 1960 up to date. The most relevant articles have been reviewed and included.Main Outcome MeasuresThe main outcome is the review of the effect of pregnancy, delivery, and postpartum on female sexuality.ResultsA total of 48 articles which specifically addressed this topic were included. Sexual function was found to have a significant global decline during pregnancy, particularly in the third trimester and this persisted for 3–6 months following delivery. The lack of adequate information about sex in pregnancy and concerns about the possible adverse obstetric outcomes are the most relevant factors responsible for the avoidance of sexual activity during pregnancy. Breast-feeding, dyspareunia, and postpartum pelvic floor dysfunction were reported as possible causes for the delay in resuming sexual intercourses after childbirth.ConclusionsCouples should be informed about the decline of libido, desire and orgasm, commonly encountered during pregnancy, particularly in the last trimester, and puerperium which may lead to reduction in sexual intercourse frequency. Serati M, Salvatore S, Siesto G, Cattoni E, Zanirato M, Khullar V, Cromi A, Ghezzi F, and Bolis P. Female sexual function during pregnancy and after childbirth.  相似文献   
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Crohn's disease is a chronic, inflammatory disease of the gastrointestinal tract, affecting both children and adults. Extracorporeal photopheresis (ECP) has been used in steroid dependent adults with moderate to severely active Crohn's disease, with response rates up to 50%, with up to 25% complete responses. A 12‐year‐old male patient had severe unremitting Crohn's disease for one year, despite treatment with anti‐inflammatory, immunosuppressive, and biologic agents. He failed elemental enteral nutrition and required total parenteral nutrition (TPN). A diverting colostomy for perforation was required. He required frequent hospitalizations and required homebound schooling. Endoscopy revealed severe inflammation and ulcerations of the entire colon. ECP was begun twice weekly for 4 weeks, then twice per week every 14 days for a total of 28 weeks. ECP was well tolerated and prednisone was gradually discontinued. He continued daily azathioprine and infliximab at 6 week intervals. TPN was weaned as enteral intake improved. Disease abatement allowed a return to school and normal activities. Endoscopy at completion of ECP course revealed normal upper tract, normal ano‐rectum, and decreased, although significant, colonic disease. This response has continued for at least 16 months since completion of ECP. We conclude that ECP is useful for pediatric patients with steroid dependent Crohn's disease and prospective evaluation is warranted. J. Clin. Apheresis 28:381–386, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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COVID-19 pandemic dramatically impacted transplantation landscape. Scientific societies recommend against the use of donors with active SARS-CoV-2 infection. Italian Transplant Authority recommended to test recipients/donors for SARS-CoV-2-RNA immediately before liver transplant (LT) and, starting from November 2020, grafts from deceased donors with active SARS-CoV-2 infection were allowed to be considered for urgent-need transplant candidates with active/resolved COVID-19. We present the results of the first 10 LTs with active COVID-19 donors within an Italian multicenter series. Only two recipients had a positive molecular test at LT and one of them remained positive up to 21 days post-LT. None of the other eight recipients was found to be SARS-CoV-2 positive during follow-up. IgG against SARS-CoV-2 at LT were positive in 80% (8/10) of recipients, and 71% (5/7) showed neutralizing antibodies, expression of protective immunity related to recent COVID-19. In addition, testing for SARS-CoV-2 RNA on donors’ liver biopsy at transplantation was negative in 100% (9/9), suggesting a very low risk of transmission with LT. Immunosuppression regimen remained unchanged, according to standard protocol. Despite the small number of cases, these data suggest that transplanting livers from donors with active COVID-19 in informed candidates with SARS-CoV-2 immunity, might contribute to safely increase the donor pool.

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