Desferrioxamine (DFO) has shown anti-proliferative and cytotoxic effects on several tumor cells. DFO is used at present in the treatment of neuroblastoma in combination with chemotherapy (D-CECaT regimen: cyclophosphamide, etoposide, carboplatin, and thiotepa). We compared the effect of continuous or intermittent exposures to DFO on 3H-thymidine uptake, viability, and cell cycle of human neuroblastoma (NB) cell lines. Our results show that continuous exposures to DFO cause dose- and time-dependent cytotoxicity of NB cells, while intermittent exposures result in significant NB cell toxicity only when using high DFO concentrations. By 3H-thymidine uptake, a significant inhibition of proliferation was observed only in continuous exposures. In addition, a consistent arrest in G1 phase was detected only in cultures treated continuously with high DFO concentrations. Our data indicate that 3H-thymidine uptake, viability, and cell cycle changes are proportional to the extent of exposure and concentration of DFO, suggesting that in vivo DFO continuous infusion may improve anti-neuroblastoma activity.

The iron chelator desferrioxamine (DFO) has been shown to inhibit the proliferation of hemopoietic progenitors and several tumor cell lines. We have compared the in viro hemopoietic inhibitory effect of desferrioxamine (DFO) and hydroxypyridones (HPOs) on hemopoietic progenitors and two human neuroectodermal (NE) tumor cell lines, NB 100 and SKNMC. Both DFO and HPOs showed a direct dose-related inhibitory effect on BFU-E and CFU-GM obtained from purified human non-T MNAC (T-lymphocyte-depleted nonadherent mononuclear cells) and CD34+ cells. DFO and HPOs displayed both an inhibitory and a cytotoxic effect on NE cell lines. We calculated the ratio between NE cell and hemopoietic cell growth inhibition for a range of concentrations of chelators. DFO showed the most satisfactory ratio. This suggests that DFO is still the most preferable chelating agent for the treatment of neuroblastoma, since it combines the highest antineuroblastoma effect with the lowest hematopoietic toxicity.

Aims and background High doses of metoclopramide are contraindicated to prevent chemotherapy-induced emesis in pediatric patients, since the incidence of extrapyramidal reactions is increased in these patients. The aim of this small study was to evaluate the antiemetic activity and the safety of tropisetron (a new selective antagonist of 5-HT3 receptors) in children who suffered nausea and vomiting during previous chemotherapy courses, despite the administration of an anxiolytic agent (hydroxyzine hydrochloride). Methods The children with a malignant neoplasm were treated for emesis with tropisetron (5 mg o.a.d. or b.i.d.) during a total of 20 cycles of chemotherapy with carboplatin combined with other antitumor agents. Results In 14 cycles (70%), there was no vomiting. There were two or less episodes of vomiting in 2 cycles (10%), 3–4 episodes in 2 cycles (10%), and no inhibition of vomiting at all in 2 cycles (10%). In 8 cycles there were no episodes of nausea (40%), in 5 cycles (25%) there were episodes of moderate nausea, and in 4 (20%) there were episodes of severe nausea. One child had a mild headache during one cycle and moderate hypotension during another. Conclusions The results suggest that tropisetron is both efficacious and safe for the treatment of pediatric patients.

We present new records of the invasive hammerhead flatworms Bipalium kewense Moseley, 1878 and Bipalium vagum Jones & Sterrer, 2005 (Platyhelminthes, Geoplanidae, Bipaliinae) from several states in Mexico based on iNaturalist and two vouchered specimens. This represents for Mexico the first review of distribution records of this group and highlights the importance of citizen science in monitoring the distribution of these ecologically important invasive predators. Methods for the collection and preservation of hammerhead flatworms, as well as an identification key, are proposed.

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