Bottled mineral waters polluted by protozoa in Mexico

A survey of protozoa polluting bottled mineral water in Mexico was carried out using samples obtained form the three best-selling brands of bottled mineral water in the country. The organisms were concentrated through filtration procedures and subsequently cultured in the sterile media. The cultures were observed over four weeks, with identification to the level of genus and species. Most commonly found were the amoebae Naegleria gruberi, Acanthamoeba astronyxis, and Vahlkampfia vahlkampfi (trophic as well as cystic stages) plus one flagellate, Bodomorpha minima. No ciliates were detected. The public health importance of the findings is obvious, since some strains of Naegleria and Acanthamoeba have the potential to cause human disease that may lead to death.

[Evaluation of psychological and social rehabilitation of the child with chronic renal failure]

Fifteen children with chronic renal failure were studied from the psychological and social viewpoints. Seven of them had been treated under a program of chronic hemodialysis; seven had been transplanted a kidney from a living donor and one from a dead donor. The degree of psychological and social rehabilitations was compared between the transplanted patients and those under chronic hemodialysis. It was observed that the latter did not achieve an acceptable degree of rehabilitation. The importance of the donor's position within the family structure, prior to the transplant, is also emphasized as the key relevant factor contributing to the family balance after the transplant.

Importance of geometry in biological sample analysis by x-ray fluorescence

The determining factors of a good analysis by x-ray fluorescence are discussed, emphasizing the importance of the geometrical arrangement, especially the excitation-source to analysis-material distance. The variation of the peak area of the Kalpha x-ray of Fe is evaluated as a function of the distance. Precautions are given for the analysis of low concentration samples as well as for obtaining the relative concentration of an element in a specific material or organ.