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Membrane transporters are involved in enormous number of physiological and pathological processes. Under oxidative stress they become targets for reactive oxygen species and its derivatives which cause protein damage and/or influence protein function(s). The molecular mechanisms of this interaction are poorly understood. Here we describe a novel lipid-mediated mechanism by which biologically important reactive aldehydes (RAs; 4-hydroxy-2-nonenal, 4-hydroxy-2-hexenal and 4-oxo-2-nonenal) modify the activity of several membrane transporters. We revealed that investigated RAs covalently modify the membrane lipid phosphatidylethanolamine (PE), that lead to the formation of different membrane active adducts. Molecular dynamic simulations suggested that anchoring of PE-RA adducts in the lipid headgroup region is primarily responsible for changes in the lipid membrane properties, such as membrane order parameter, boundary potential and membrane curvature. These caused the alteration of transport activity of mitochondrial uncoupling protein 1, potassium carrier valinomycin and ionophore CCCP. In contrast, neither direct protein modification by RAs as previously shown for cytosolic proteins, nor its insertion into membrane bilayers influenced the studied transporters. Our results explain the diversity of aldehyde action on cell proteins and open a new field in the investigation of lipid-mediated effects of biologically important RAs on membrane receptors, channels and transporters.

Objectives To compare uterine rupture rates in women having a medical abortion receiving gemeprost alone to those receiving mifepristone plus gemeprost. Study design We reviewed the records of women undergoing medical abortion at 13 0/7–23 6/7 weeks from January 2007 to December 2014 at a single center in Italy. Prior to January 2011, we used gemeprost 1 mg vaginally every 3 h up to a maximum of five doses. After January 2011, we added mifepristone 200 mg orally 24 h prior to the same gemeprost protocol. The primary outcome of the study was the incidence of uterine rupture. We compared the outcome between women receiving gemeprost alone with the combination of gemeprost and mifepristone. Results One thousand and sixty-one (58.5%) and 753 (41.5%) women underwent medical abortion in the gemeprost-alone and the gemeprost/mifepristone groups, respectively. Five (0.47%) uterine ruptures occurred in the gemeprost and four uterine ruptures occurred in the gemeprost/mifepristone groups, respectively (0.53%) (p=.89). All uterine ruptures occurred in women with prior cesarean delivery. Conclusions We rep orted no difference in the incidence of uterine rupture between the gemeprost-alone and gemeprost and mifepristone groups. Implications Uterine rupture is a rare complication of second-trimester medical abortion with gemeprost. Use of mifepristone prior to gemeprost does not affect this risk.

Objectives To compare surgical outcomes of different types of intracorporeal sutures for laparoscopic posterior myomectomy, by a prospective randomized study. Study design Prospective randomized study on 47 patients with single posterior intramural myoma (4–7 cm in diameter) undergoing laparoscopic myomectomy. The patients enrolled were divided into two groups, one operated using conventional suture in double strand, and the other with bidirectional barbed suture Stratafix. The main outcome measures were suturing time, peri-operative variables, and post-operative adhesions in both groups. Results The mean operative time was shorter with the Stratafix™ than with the conventional suture (66.3 ± 8.2 vs. 73 ± 8 min; p = 0.005). Suturing time was significantly shorter in the Stratafix™ than in the control group (8.8 ± 2.4 vs. 15.5 ± 2.8 min; p = 0.001). Intraoperative bleeding was significantly less in the Stratafix group ( p = 0.0012). Conversely, there was no statistically significant difference for postoperative adhesions between the two groups (26.7% vs. 21.4% p = 0.5). Conclusions The use of barbed suture may reduce operative time, suturing time, and blood loss. No difference in post operative adhesions was found.