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PubMed2003

Chemokines accumulate in the lungs of rats with severe pulmonary embolism induced by polystyrene microspheres.

Pulmonary thromboembolism (PEm) is a serious and life threatening disease and the most common cause of acute pulmonary vascular occlusion. Even following successful treatment of PEm, many patients experience long-term disability due to diminished heart and lung function. Considerable damage to the lungs presumably occurs due to reperfusion injury following anti-occlusive treatments for PEm and the resulting chronic inflammatory state in the lung vasculature. We have used a rat model of irreversible PEm to ask whether pulmonary vascular occlusion in the absence of reperfusion is itself sufficient to induce an inflammatory response in lungs. By adjusting the severity of the vascular occlusion, we were able to generate hypertensive and nonhypertensive PEm, and then examine lung tissue for expression of CXC and C-C chemokine genes and bronchoalveolar lavage (BAL) fluid for the presence of chemokine proteins. Hypertensive and nonhypertensive PEm resulted in increased expression of both CXC and C-C chemokines genes in lung tissues. Hypertensive PEm was also associated with a 50-100-fold increase in protein content in lung BAL fluid, which included the CXC chemokines cytokine-induced neutrophil chemoattractant and macrophage-inflammatory protein 2. The presence of chemokines in BALs was reflected by a potent neutrophil chemotactic activity in in vitro chemotaxis assays. Abs to cytokine-induced neutrophil chemoattractant blocked the in vitro neutrophil chemotactic activity of BAL by 44%. Our results indicate that the ischemia and hypertension associated with PEm are sufficient to induce expression of proinflammatory mediators such as chemokines, and establish a proinflammatory environment in the ischemic lung even before reperfusion.

Animals↗
PubMedDate not supplied

Evaluation of a hypercrosslinked polystyrene, MN-200, as a sorbent for the preconcentration of volatile organic compounds in air.

Breakthrough volumes, average percentage recoveries, and storage stabilities were obtained for vapors of 8 volatile organic compounds (pentane, octane, undecane, isooctane, cyclohexane, toluene, methanol, and dichloromethane) on a new adsorbent material, Hypersol-Macronet, MN-200. Breakthrough volumes were estimated as half of the gas chromatographic specific retention volumes at 20 degrees C for the compounds. Recoveries of the adsorbates were determined by both solvent extraction and thermal desorption methods. The results obtained compare favorably with those for Tenax GR (values reported in the published literature and others obtained in our laboratory). Results of storage stability studies on MN-200 meet the criterion for acceptability (<10% loss). High adsorption capacity for very volatile and polar compounds, combined with ease of desorption of less volatile compounds, render MN-200 a highly promising adsorbent for sampling volatile organic compounds in indoor and outdoor air.

Adsorption↗
PubMed2002

[Colonic necrosis caused by sodium polystyrene (kayexalate) in hemodialysis: myth or reality? Two case reports].

Among gastro-intestinal complications reported in uremic or transplanted patients, colonic necrosis due to Kayexalate and sorbitol is not so unusual for english authors. This iatrogenic event is probably underestimated by physicians and pathologists. In France, neither literature nor pharmacovigilance refer this complication but Vidal dictionary advises against such association. We thought of interest to report 2 representative observations and, after reviewing literature, to discuss diagnostics circumstances and etiopathogenic hypothesis and then to give some advices.

Cation Exchange Resins↗