An analytical solution to solute transport in continuous arterio-venous hemodiafiltration (CAVHD)

In conventional intermittent hemodialysis, the overall mass transfer coefficient (Ko) of a dialyser is mostly calculated at zero ultrafiltration and at relatively high dialysate flow rates. In continuous arterio-venous hemodiafiltration (CAVHD), the dialysate flow rates are low as comparable to the rates of ultrafiltration flows, making the dialysis treatment as slow as possible. Therefore the overall mass transfer coefficient (Kd) of a CAVHD hemofilter has to be calculated in the presence of ultrafiltration. A mathematical model of CAVHD is presented in order to calculate the diffusive mass transfer coefficient (Kd) for a solute when blood, filtrate and dialysate flow rates and solute concentrations are known. The ultrafiltration volume flux (Jv) is assumed to vary linearly along the axial direction of the hemofilter. The calculated mass transfer coefficient Kd shows that at high values of dialysate flow and low values of ultrafiltration, the overall mass transfer coefficient (Kd) of a CAVHD hemofilter equals mass transfer coefficient (Ko) of a dialyser in conventional intermittent hemodialysis. Also, the calculated mass transfer coefficient Kd shows no significant differences when the ultrafiltration volume flux is assumed to be constant along the length of the hemofilter if no backfiltration occurs in the hemofilter

Feasibility of intensity-modulated and image-guided radiotherapy for functional organ preservation in locally advanced laryngeal cancer

Purpose: The study aims to assess the feasibility of intensity-modulated and image-guided radiotherapy (IMRT, and IGRT, respectively) for functional preservation in locally advanced laryngeal cancer. A retrospective review of 27 patients undergoing concurrent chemoradiation for locally advanced laryngeal cancers (8 IMRT, 19 IGRT) was undertaken. In addition to regular clinical examinations, all patients had PET imaging at 4 months and 10 months after radiotherapy, then yearly. Loco-regional control, speech quality and feeding-tube dependency were assessed during follow-up visits. Results: At a median follow-up of 20 months (range 6-57 months), four out of 27 patients (14.8%) developed local recurrence and underwent salvage total laryngectomy. One patient developed distant metastases following salvage surgery. Among the 23 patients who conserved their larynx with no sign of recurrence at last follow-up, 22 (95%) reported normal or near normal voice quality, allowing them to communicate adequately. Four patients (14.8%) had long-term tube feeding-dependency because of severe dysphagia (2 patients) and chronic aspiration (2 patients, with ensuing death from aspiration pneumonia in one patient). Conclusions and Clinical Relevance: Functional laryngeal preservation is feasible with IMRT and IGRT for locally advanced laryngeal cancer. However, dysphagia and aspiration remain serious complications, due most likely to high radiation dose delivery to the pharyngeal musculatures. © 2012 Nguyen et al

Cytotoxicity of Triorganophosphinegold(I) Complexes of Thiobenzoate

The preparation and characterization of two triorganophosphinegold(I) complexes containing the anion derived from thiobenzoic acid are described. The cytotoxicity of these complexes has been investigated along with that of triphenylphosphinegold(I) mercaptopurinate, a known anti-tumor compound, against a variety of human cell lines. The complexes showed moderate to high cytotoxicity (ID50 250 – 2500 ng/ml)

Feasibility of Tomotherapy-Based Image-Guided Radiotherapy to Reduce Aspiration Risk in Patients with Non-Laryngeal and Non-Pharyngeal Head and Neck Cancer

Purpose: The study aims to assess the feasibility of Tomotherapy-based image-guided radiotherapy (IGRT) to reduce the aspiration risk in patients with non-laryngeal and non-hypopharyngeal cancer. A retrospective review of 48 patients undergoing radiation for non-laryngeal and non-hypopharyngeal head and neck cancers was conducted. All patients had a modified barium swallow (MBS) prior to treatment, which was repeated one month following radiotherapy. Mean middle and inferior pharyngeal dose was recorded and correlated with the MBS results to determine aspiration risk

Nuevos registros de Amphisbaena fuliginosa Linnaeus, 1758 (Squamata: Amphisbaenidae) para la Amazonia Boliviana y primer registro para el departamento del Beni

Los especímenes de Amphisbaena fuliginosa representan un aporte importante para el mejor conocimiento sobre la distribución de la especie en Bolivia. Sin embargo, comparando los caracteres merísticos de los tres especímenes del presente estudio con los descritos por Vanzolini (2002a) para las diferentes subespecies de A. fuliginosa, resulta que dos de estas (CIRAH-951, 1000) coinciden con A. fuliginosa bassleri y una (CIRAH-1001) con A. fuliginosa wiedi (excepto en los anillos de la cola) y no así con el patrón de color descritos por este autor. Además, constituyen los primeros registros para el departamento del Beni (Riberalta), ciudad ubicada a orillas del río Beni en la Amazonia boliviana y una de las regiones escasamente estudiadas, pero altamente diversa.Asociación Herpetológica Argentin