A new precursor (Ag/CS/PNIPA) arranged as a nanogel (nanoreactor) is obtained from the aqueous mixture of Ag, chitosan (CS) and poly(N-isopropylacrylamide) (PNIPA). A model synthetic system based on the thermally induced aqueous silver ions-CS reaction to form silver nanoparticles (AgNP) is used as a starting point to assess the PNIPA role as a thermo-sensitive additive of synthesis in a low content for the production of size-controlled AgNP. As expected, the PNIPA phase transition produced by the temperature increase leads to chitosan nanogel contraction, lowering the diffusion of ionic species.
View Article and Find Full Text PDFObjective: the aim of this study was to assess the results of mechanochemical endovenous ablation either in the primary or recurrent saphenous vein insufficiency, including only patients with veno-venous shunt type III.
Methods: retrospective analysis of a prospective study of patients with symptomatic chronic venous insufficiency who underwent ClariVein® technique. A total of 134 saphenous veins were included between August 2017 and August 2018.
The synthetic system to produce silver nanoparticles (AgNP) based on the thermally activated reduction of aqueous silver ions by chitosan (CS) polysaccharide is investigated to unravel the physicochemical processes controlling AgNP nucleation and growth. An anomalous preeminence of AgNP nucleation over growth is found for conditions under which the opposite trend is obeyed for AgNP synthesized from soluble precursors in homogeneous media. The behavior is modeled assuming the formation of a tridimensional supramolecular structure from silver ions / CS´s amino groups coordination complexes, driving the crosslinking within polymer folding and aggregation in shaping random coils.
View Article and Find Full Text PDFBackground: Type 2 endoleaks (T2Es) are the main cause of reintervention after endovascular repair of abdominal aortic aneurysms (EVAR). The objective of this study is to quantify success rates of T2E treatment.
Methods: This study involves a retrospective analysis of a prospectively maintained database containing data on all consecutive patients treated for a T2E between 2003 and 2017 in a single center.
Background: The objective of this report is to present a challenging case of a mycotic aneurysm of the innominate artery (IA) in a patient with a bovine aortic arch.
Materials And Methods: An 85-year-old woman presented with intermittent fever and positive blood cultures for Staphylococcus aureus. An echocardiogram and a positron emission tomography-computed tomography were performed, showing a hypermetabolic dilation of the IA compatible with a mycotic aneurysm with a type one bovine aortic arch.
Purpose:: Endograft infection is an infrequent but one of the most serious and challenging complications after endovascular aortic repair. The aim of this study was to assess the management of this complication in a tertiary center.
Case Series:: A retrospective analysis of a prospective database was performed including all patients who underwent elective endovascular abdominal aortic repair (EVAR) from 2003 to 2016 in a tertiary center.
We show that homogeneously mixed self-assembled monolayers (SAMs) of mercaptoalkanoic acids of different chain lengths can be used to build up a pH-sensitive supramolecular switch. The acids with short and long alkyl chains interact via the strong hydrogen bond between carboxylic acid groups. The pH acts as a trigger by breaking or restoring the hydrogen bond interaction in basic or acidic solutions, respectively.
View Article and Find Full Text PDFHypothesis: Heterogeneous nucleation of silver oxide (Ag2O) onto oxide microparticles (OMPs) followed by spontaneous thermal decomposition produce nanostructures made of OMPs decorated with silver nanoparticles (OMP|AgNPs).
Experiments: Colloidal chemistry methods have been used to produce the decoration of OMPs with silver nanoparticles (AgNPs), by carrying out the Ag2O precipitation/thermal decomposition. The process is driven in water enriched acetone medium containing NaOH, NH3, AgNO3 and SiO2MPs as substrate.
Primary Sjögren's syndrome (pSS) is an autoimmune disorder of the exocrine glands presenting with progressive ocular and oral dryness, parotid gland enlargement, and often with extraglandular manifestations. In this group of patients the risk of development of non-Hodgkin's lymphoma is 16-fold compared to healthy population, mainly of the MALT lymphoma type. This case reports a 52-year-old woman with pSS developing a progressively growing mass at face and neck compatible with blastoid variant mantle cell lymphoma and a fatal outcome.
View Article and Find Full Text PDFIntroduction: The genetic diversity of Plasmodium falciparum has been one of the major obstacles for the success of anti-malaria drug therapy. It provides the parasite an ability to evade the host's immune response by generating changes in its antigenic composition and resistance to antimalarial drugs.
Objective: The genetic diversity of P.
We evaluated the Plasmodium vivax polymorphism by studying the Pvmsp-3alpha gene's polymorphic region by PCR-RFLP in 55 samples from patients living in Tierralta, Colombia. Three different sizes of the Pvmsp-3 alpha gene were found, type A (1,900 bp), type B (1,500 bp) and type C (1,100 bp); most of the samples were type A (96.4 %).
View Article and Find Full Text PDFIntroduction: The decrease in the efficacy of antimalarial drugs in the world and in Colombia hampers its control.
Objective: The in vivo therapeutic efficacy of the amodiaquine+sulfadoxine-pyrimethamine combination was evaluated in the treatment of uncomplicated Plasmodium falciparum malaria and of chloroquine for P. vivax malaria.