Endovascular stenting for chronic femoro-iliac venous obstructive disease: Clinical efficacy and short-term outcomes.

PURPOSE: To report the clinical efficacy and mid-term outcomes of endovascular treatment in patients with chronic, symptomatic, post-thrombotic femoro-iliac venous obstruction. MATERIALS AND METHODS: Forty-two patients with post-thrombotic syndrome (PTS) presenting with femoro-iliac venous obstructive lesions treated in our institution by endovascular approach between March 2012 and October 2017 were retrospectively included. There were 27 women and 15 men with a mean age of 47.3±17 (SD) years (range: 22-86 years). Procedure included first venous recanalization, then pre-dilatation and self-expandable metallic stenting of the narrowed or occluded iliac and/or femoral veins. Severity of PTS and quality of life were assessed at baseline and 3 months after the intervention respectively, using Villalta score and Chronic Venous Insufficiency Questionnaire (CIVIQ-20) scale. Imaging follow-up evaluation of stent patency was based on the results of duplex Doppler ultrasound and computed tomography. RESULTS: Immediate technical success was achieved in 41/42 (97.6%) patients, without any major complications. Primary patency, primary assisted patency and secondary patency at the end of the median imaging follow-up of 18.1 months (IQR, 9.7-34.4) were achieved in 29/42 (66.7%) patients, 33/42 (78.6%) patients and 37/42 (88.1%) patients, respectively. Median Villalta and CIVIQ-20 scores decreased from 14 (IQR, 10-19) and 57 (IQR, 39-72) at baseline, respectively, to 5 (IQR, 2-9) and 30 (IQR, 24-50) 3 months after the procedure, respectively (P<0.0001), showing significant decrease in the severity of PTS and improvement in the quality of life. The multiple linear regression model showed that both baseline Villalta and CIVIQ-20 scores ([95% CI: -7.80-3.79; P<0.0001] and [95% CI: 0.07-0.20; P<0.0001], respectively), age (95% CI: 0.04-0.19; P=0.002) and stenting expanse (95% CI: 0.97-5.65; P=0.006) were independent variables related to Villalta gain. Baseline Villalta (95% CI: 0.89-2.23; P<0.0001) was the single independent variable related to CIVIQ-20 gain. CONCLUSION: This study confirms the high clinical efficacy and favorable mid-term outcomes of endovascular stenting in patients with chronic symptomatic femoro-iliac venous obstructive lesions.

Biosynthesis of lead nanoparticles by the aquatic water fern, Salvinia minima Baker, when exposed to high lead concentration.

Salvinia minima Baker is a small floating aquatic fern that is efficient for the removal and storage of heavy metals such as lead and cadmium. In this study, we report that lead removal by S. minima causes large accumulation of lead inside the cells in the form of nanoparticles (PbNPs). The accumulation pattern of lead was analyzed in both, submerged root-like modified fronds (here named "roots"), and in its aerial leaf-like fronds ("leaves"). Analysis by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) confirmed the biosynthesis of PbNPs by the plant. In both, roots and leaves, PbNPs were found to accumulate almost exclusively at the cell wall and closely associated to the cell membrane. Two types of PbNPs shapes were found in cells of both tissues, those associated to the cell wall were quasi-spherical with 17.2±4.2 nm of diameter, while those associated to the cell membrane/cytoplasm were elongated. Elongated particles were 53.7±29.6 nm in length and 11.1±2.4 nm wide. Infrared spectroscopy (IR) results indicate that cellulose, lignin and pectin are the major components that may be acting as the reducing agents for lead ions; these findings strongly suggest the potential use of this fern to further explore the bio-assisted synthesis of heavy metal nanostructures.