Rivaroxaban for the prevention of venous thromboembolism after radiofrequency ablation of saphenous veins concomitant with miniphlebectomy, sclerotherapy, or no treatment of varicose tributaries.

OBJECTIVE: To assess the efficacy and safety of once-daily 10 mg rivaroxaban for venous thromboembolism prophylaxis after ClosureFast radiofrequency ablation (RFA) of saphenous veins. METHOD: The medical records of patients, who had a Caprini score of ≥3, underwent RFA, received prophylactic rivaroxaban for five days, and completed follow up at one month were reviewed for efficacy (a combination of endovenous heat-induced thrombosis [EHIT] grade of 2-4, any symptomatic or asymptomatic deep vein thrombosis [DVT], and symptomatic pulmonary embolism [PE]) and safety (a combination of major and clinically relevant non-major [CRNM] bleeding) outcomes. RESULTS: The results of RFA for 248 great saphenous and 24 small saphenous veins with the concomitant miniphlebectomy (63.8%) and sclerotherapy (16.5%) were analyzed. The primary efficacy outcome occurred in 5 of 218 (2.3%; 95%CI, 1.0-5.3%) patients: three EHITs and two symptomatic DVTs. The CRNM bleeding was reported in two patients (0.9%; 95% CI, 0.2-3.3%). No difference was observed in comparison with 79 similar patients who received 40 mg of subcutaneous enoxaparin during the same time period. CONCLUSION: Once-daily 10 mg rivaroxaban is suitable for VTE prophylaxis after RFA of saphenous veins.

Kinetics of lactose and rhamnose oxidation over supported metal catalysts.

Several mono- and bimetallic Pd, Pt, Rh and Ru supported on alumina and active carbon catalysts were characterized by CO chemisorption, nitrogen adsorption, XPS and XRD and acidity titrations were performed for active carbon supported catalysts. These catalysts were tested in oxidation of two sugars, namely lactose and rhamnose, at 60 °C and at 70 °C under slightly alkaline conditions (pH 8) with molecular oxygen. The results revealed that there is an optimum metal particle size in a range of 3-10 nm giving the highest initial TOFs for both oxidations. Furthermore, the catalytic activities and conversions were related to other catalyst properties, such as the type and amount of promoters and the presence of different phases. In situ catalyst potential measurements revealed that there is an inverse correlation between the increase of catalyst potential as a function of sugar conversion and the catalyst activity after prolonged reaction times. This method is a valuable tool for in situ characterization of catalysts correlating well with their activities.

Reaction products and transformations of intermediates in the aqueous-phase reforming of sorbitol.

Aqueous phase reforming of sorbitol over Pt supported on an alumina catalyst is investigated, in order to identify the intermediates involved in the transformation of the initial feed. Parameters such as the sorbitol feed rate and temperature are studied. To identify the intermediates, an approach based on analysis of the gas and liquid phases as well as the total carbon content was developed. According to analysis by gas chromatography combined with mass spectrometry of volatile substances collected with solid-phase microextraction, over 260 compounds are involved in the transformation of sorbitol. Of these, 50 of the major products are identified with high reliability. It is shown that a great variety of compounds, bearing different functionalities, form part of the reaction network. The formation of the majority of identified compounds is explained and a reaction network for the formation of sorbitol and intermediate molecules transformation is proposed.