Endovascular treatment for massive haemoptysis due to pulmonary pseudoaneurysm: report of 23 cases.

PURPOSE: To evaluate the safety and effectiveness of endovascular treatment for massive haemoptysis caused by pulmonary pseudoaneurysm (PAP). METHODS: The clinical data, imaging data, and endovascular treatment protocol of 23 patients with massive haemoptysis caused by continuous PAP were retrospectively analysed. The success, complications, postoperative recurrence rate, and influence of the treatment on pulmonary artery pressure were also evaluated. RESULTS: Nineteen patients with a bronchial artery-pulmonary artery (BA-PA) and/or nonbronchial systemic artery-pulmonary artery (NBSA-PA) fistula underwent bronchial artery embolization (BAE) and/or nonbronchial systemic artery embolization (NBSAE) + pulmonary artery embolization (PAE). The pulmonary artery (PA) pressures before and after embolization were 52.11 ± 2.12 (35-69 cmH2O) and 33.58 ± 1.63 (22-44 cmH2O), respectively (P = 0.001). Four patients did not have a BA-PA and/or NBSA-PA fistula. Embolization was performed in two patients with a distal PAP of the pulmonalis lobar arteria. Bare stent-assisted microcoils embolization was performed in the other two patients with a PAP of the main pulmonary lobar arteries. The PA pressures of the four patients before and after treatment were 24.50 ± 1.32 (22-28 cmH2O) and 24.75 ± 1.70 (22-29 cmH2O), respectively (P = 0.850). The technique had a 100% success rate with no serious complications and a postoperative recurrence rate of 30%. CONCLUSION: Endovascular treatment is safe and effective for massive haemoptysis caused by PAP. BAE and/or NBSAE can effectively reduce pulmonary hypertension in patients with a BA-PA and/or NBSA-PA fistula.

Effects of Strand Lay Direction and Crossing Angle on Tribological Behavior of Winding Hoist Rope.

Friction and wear behavior exists between hoisting ropes that are wound around the drums of a multi-layer winding hoist. It decreases the service life of ropes and threatens mine safety. In this research, a series of experiments were conducted using a self-made test rig to study the effects of the strand lay direction and crossing angle on the winding rope's tribological behavior. Results show that the friction coefficient in the steady-state period shows a decreasing tendency with an increase of the crossing angle in both cross directions, but the variation range is different under different cross directions. Using thermal imaging, the high temperature regions always distribute along the strand lay direction in the gap between adjacent strands, as the cross direction is the same with the strand lay direction (right cross contact). Additionally, the temperature rise in the steady-state increases with the increase of the crossing angle in both cross directions. The differences of the wear scar morphology are obvious under different cross directions, especially for the large crossing angle tests. In the case of right cross, the variation range of wear mass loss is larger than that in left cross. The damage that forms on the wear surface is mainly ploughing, pits, plastic deformation, and fatigue fracture. The major wear mechanisms are adhesive wear, and abrasive and fatigue wear.

Novel polyelectrolyte carboxymethyl konjac glucomannan-chitosan nanoparticles for drug delivery. I. Physicochemical characterization of the carboxymethyl konjac glucomannan-chitosan nanoparticles.

Carboxymethyl konjac glucomannan-chitosan (CKGM-CS) nanoparticles, which are well dispersed and stable in aqueous solution, were spontaneously prepared under very mild conditions via polyelectrolyte complexation. The physicochemical properties of the nanoparticles were identified by Zetasizer 3000 and Fourier transform infrared. It was found that at various CKGM and CS concentrations the particles ranged in size from approximately 50 to 1200 nm, and the zeta potential from 15 to 45 mV. By changing pH value of the medium and increasing the concentration of salt, the mean size of the particles increased and the zeta potential decreased. Also, investigations on the encapsulation efficiency of the bovine serum albumin loaded CKGM-CS nanoparticles were also undertaken. This nanoparticulate system driven by complex formation shows potential as an advanced drug delivery system for water-soluble drugs.

Novel polyelectrolyte carboxymethyl konjac glucomannan-chitosan nanoparticles for drug delivery. II. Release of albumin in vitro.

Carboxymethyl konjac glucomannan-chitosan (CKGM-CS) nanoparticles were spontaneously prepared under very mild conditions via polyelectrolyte complexation. Bovine serum albumin (BSA), as a model protein drug, was incorporated into the CKGM-CS nanoparticles. The physicochemical properties of the BSA-loaded nanoparticles were identified by Zetasizer 3000 and FTIR spectrophotometry. Their sizes were from 330 nm to 900 nm; zeta potentials were positive according to varies CKGM/CS ratios. The encapsulation efficiency was up 20%. The release behavior in vitro of BSA from the nanoparticles was also investigated. We could find that the BSA release from the CKGM-CS nanoparticles is much more influenced by the CS coating layer than by the CKGM inner structure. And the CKGM-CS matrices not only exhibited pH-responsive properties, but ionic strength-sensitive properties. These systems may present a potential for pulsatile protein drug delivery.

Fabrication of temperature-sensitive imprinted polymer hydrogel.

Weakly cross-linked temperature sensitive gels that memorize 4-aminopyridine molecules were designed and synthesized. The polymer gels show special selectivity, good thermo-sensitivity and reusability, which would have an enormous potential of application in drug controlled release systems.

Design of temperature sensitive imprinted polymer hydrogels based on multiple-point hydrogen bonding.

Weakly cross-linked temperature sensitive imprinted polymer hydrogels that recognize L-pyroglutamic acid (Pga) molecules via multiple-point hydrogen bonding were designed and synthesized. The amount of adsorption for Pga in imprinted hydrogels is 3-4 times higher than that in non-imprinted hydrogels. The selectivity test of imprinted polymer gels was carried out by using a series of structurally related compounds Pga, pyrrolidine, 2-pyrrolidone, L-proline as substrates. The results show that imprinted polymer gels exhibit high selectivity for Pga as compared to all the other tested substrates. The imprinted polymer hydrogels show good temperature sensitivity, special selectivity and reusability, suggesting that the polymer hydrogels would have an enormous potential for application in controlled drug release and separation field.