Special situations in inflammatory bowel disease: First Latin American consensus of the Pan American Crohn's and Colitis Organisation (PANCCO) (Second part). / Situaciones especiales en la enfermedad inflamatoria intestinal: primer consenso latinoamericano de la Pan American Crohn's and Colitis Organisation (PANCCO) (Segunda parte).

This is the first Latin American Consensus of the Pan American Crohn's and Colitis Organisation (PANCCO) regarding special situations in patients with inflammatory bowel disease (IBD). The aim of this consensus is to raise awareness in the medical community in all Latin American countries with respect to pregnancy, vaccinations, infections, neoplasms, including colorectal cancer, and pediatric issues in patients with IBD.

Impact of long-term wastewater irrigation on sorption and transport of atrazine in Mexican agricultural soils.

In the Mezquital Valley, Mexico, crops have been irrigated with untreated municipal wastewater for more than a century. Atrazine has been applied to maize and alfalfa grown in the area for weed control for 15 years. Our objectives were to analyse (i) how wastewater irrigation affects the filtering of atrazine, and (ii) if the length of irrigation has a significant impact. We compared atrazine sorption to Phaeozems that have been irrigated with raw wastewater for 35 (P35) and 85 (P85) years with sorption to a non-irrigated (P0) Phaeozem soil under rainfed agriculture. The use of bromide as an inert water tracer in column experiments and the subsequent analysis of the tracers' breakthrough curves allowed the calibration of the hydrodynamic parameters of a two-site non equilibrium convection-dispersion model. The quality of the irrigation water significantly altered the soils' hydrodynamic properties (hydraulic conductivity, dispersivity and the size of pores that are hydraulically active). The impacts on soil chemical properties (total organic carbon content and pH) were not significant, while the sodium adsorption ratio was significantly increased. Sorption and desorption isotherms, determined in batch and column experiments, showed enhanced atrazine sorption and reduced and slower desorption in wastewater-irrigated soils. These effects increased with the length of irrigation. The intensified sorption-desorption hysteresis in wastewater-irrigated soils indicated that the soil organic matter developed in these soils had fewer high-energy, easily accessible sorption sites available, leading to lower and slower atrazine desorption rates. This study leads to the conclusion that wastewater irrigation decreases atrazine mobility in the Mezquital valley Phaeozems by decreasing the hydraulic conductivity and increasing the soil's sorption capacity.

[Recalibration of the lumbar canal, an alternative to laminectomy in the treatment of lumbar canal stenosis]. / Le recalibrage du canal lombaire, alternative à la laminectomie dans le traitement des sténoses du canal lombaire.

A technique is described for widening the lumbar vertebral canal in the treatment of lumbar stenosis. This method, which preserves part of the posterior arches, has the aim of avoiding the instability which accompanies extensive laminectomies of the whole lumbar spine. The preservation of the posterior arches allows a ligamentoplasty to be made with dacron in stable spines and a combined fusion with internal fixation applied to the posterior arches to be made in cases of spondylolisthesis. The results of a prospective series of 32 patients have confirmed the effectiveness of the method both on the stenosis and on the post-operative spinal stability.