A new rapid protocol for 226Ra separation and preconcentration in natural water samples using molecular recognition technology for ICP-MS analysis

A new rapid protocol for ²²⁶Ra separation and preconcentration in natural water samples was developed before its determination by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). For this purpose, the commercially available Ra specific resin AnaLig^® Ra-01 was used. This resin shows a high selectivity for radium in a large range of acid concentrations and no affinity or possible elution of ²²⁶Ra interfering elements. The distribution coefficients of Ra and other elements over a wide range of acid (HCl and HNO₃) concentrations were obtained. Due to the high radium selectivity, the new developed protocol uses only 50 mg of dry resin and its performance was evaluated using 100 mL of three natural waters with different ionic strengths, spiked with a known quantity of ²²⁶Ra. Radium was successfully separated and preconcentrated yielding recoveries ranging between 72% and 86%. In parallel with the characterisation of the resin sorption properties, a detailed study of polyatomic interferences was performed on our ICP-MS allowing to identify the prominent elements favouring interferences at m/z = 226. Furthermore, a ²²⁶Ra sensitivity comparison between different ICP-MS instruments and configurations was done in order to determine high sensitivity conditions for radium analysis.

[Survey of general practitioners management of erysipelas]

PURPOSE

A few studies only have focused on ambulatory management of erysipelas.

METHODS

To assess the diagnostic and therapeutic management of erysipelas by general practitioners, and their adherence to the French Society of Infectious Diseases and Dermatology joint 2000 recommendations, we surveyed 114 general practitioners during a 1 year period (from May 1st, 2005 to April 30th, 2006).

RESULTS

Seventy-three general practitioners accepted to participate to the study and 54 cases of erysipelas were reported. Median age of patients was 63 years (range, 18-94) and sex ratio was 0.77. Lower limbs were affected in 83% out of the cases. A skin lesion was reported in 65% of the cases. None of the 15 doppler ultrasonography that were performed identified deep vein thrombosis. Five patients (9%) were initially hospitalized. Only 18% out of the patients were treated by amoxicillin. Most prescribed antimicrobial agents were pristinamycin (31%) and amoxicillin-clavulanate (27%). Median duration of treatment was 10 days. Six patients received an anti-inflammatory drug. Among the 44 patients who had a follow-up visit, 37 patients (84%) recovered and two patients were hospitalized after this follow-up assessment. Two patients experienced a recurrence of erysipelas during the study.

CONCLUSION

As previously reported in the literature, outcome of erysipelas after ambulatory management remains excellent, although recommendations are poorly followed.

Membrane interactions of a new class of anticancer agents derived from arylchloroethylurea: a FTIR spectroscopic study

We have investigated the interaction between a new class of antineoplastic agents derived from arylchloroethylurea (CEU) and different lipids such as dimyristoylphosphatidylcholine (DMPC) in the absence and presence of 30 mol% of cholesterol, dimyristoylphosphatidylglycerol (DMPG) and a mixture made of 1-palmitoyl-2-oleylphosphatidylcholine (POPC) and DMPC by Fourier transform infrared (FTIR) spectroscopy. The results indicate that the drugs incorporate in the bilayer and cause a decrease of the phase transition temperature and an increase of the conformational disorder of the lipid acyl chains. These effects are dependent on the nature (degree of branching, length of the alkyl chain and presence of a sulfur atom), as well as on the position of the R substituent and are related to the cytotoxicity of the drugs. More specifically, the more cytotoxic drugs, such as 4-sec-butyl CEU, are those having a bulky branched substituent and those for which the disordering effect on the lipid bilayer is the greatest. On the other hand, the disordering effect is small for the long chain CEUs, such as 4-n-hexadecyl CEU, which have been shown to have weak cytotoxic activity.