Resultados preliminares do tratamento de insuficiência venosa grave com termoablação da veia safena magna por técnica endovascular com laser de diodo 980nm desenvolvido no Brasil, associado à escleroterapia com polidocanol

The endovenous laser ablation (EVLA) of the insufficient saphenous vein has similar results to open conventional surgery, but less morbidity. The echo-guided polidocanol foam sclerotherapy technique has been used for the same purpose. The combined techniques may play a role for more severe diseases, such as those with varicose ulcers. An EVLA device (called VELAS) has been developed in the Optics and Photonics Research Center of USP-São Carlos in agreement with FMB-UNESP. In this study, we present the preliminary results of the VELAS device (MMO 980nm diode) in patients with chronic venous ulcer, associated with echo-guided polidocanol foam sclerotherapy for the treatment of varicosities. Primary outcomes were healing time of the venous ulcer, occlusion of the treated veins and treatment-related adverse events. We included 12 patients with insufficient saphenous vein and chronic venous ulcer. Initially, we treated all of them with thermoablation of the insufficient saphenous vein (VELAS), on an outpatient basis, with local anesthesia. After one week of the procedure, we sclerosed the varicosities with polidocanol foam (Tessari technique). The national VELAS device was easily handled. Total venous occlusion occurred in 83.3% of the patients (in seven days) and the association of the techniques was responsible for a wound healing rate of 83.3%, with no adverse events

On the role of the two extracytoplasmic substrate-binding domains in the ABC transporter OpuA

Members of two transporter families of the ATP-binding cassette (ABC) superfamily use two or even four extracytoplasmic substrate-binding domains (SBDs) for transport. We report on the role of the two SBDs in the translocation cycle of the ABC transporter OpuA from Lactococcus lactis. Heterooligomeric OpuA complexes with only one SBD or one functional and one non-functional SBD (inactivated by covalent linkage of a substrate mimic) have been constructed, and the substrate binding and transport kinetics of the purified transporters, reconstituted in liposomes, have been determined. The data indicate that the two SBDs of OpuA interact in a cooperative manner in the translocation process by stimulating either the docking of the SBDs onto the translocator or the delivery of glycine betaine to the translocator. It appears that one of these initial steps, but not the later steps in translocation or resetting of the system to the initial state, is rate determining for transport. These new insights on the functional role of the extracytoplasmic SBDs are discussed in the light of the current knowledge of substrate-binding-protein-dependent ABC transporters