Cell specific ultrasound effects are dose and frequency dependent

Ultrasound is widely used in clinical practice, mostly in diagnostic studies, but increasingly in therapeutic applications as well. This may be the case in acceleration of wound healing or treatment of cancer. Still, little is known about the direct effect of frequency or energy density of the ultrasound upon the cells themselves. We therefore investigated the impact of three different protocols using high, medium and low energy densities at three different frequencies on normal endothelial and epithelial as well as carcinoma cell lines (neuroblastoma and adenocarcinoma cell lines).Proliferation of endothelial and epithelial cell lines was significantly increased depending on the frequency and energy density applied. No influence on actin cytoskeleton formation was seen in these cells after treatment, while a significant decrease in the density of microvilli and the length of filopodia in the epithelial cell line could be noted. The proliferation rate of the carcinoma cell lines was reduced and cells destroyed. Apoptosis was induced in the adenocarcinoma cells after ultrasound exposure. Additionally, the expression of neurofilament was increased in neuroblastoma cells as evidence of beginning differentiation.So, different settings of frequency and energy density in an ultrasonic treatment protocol lead to different impacts on proliferation, morphology and differentiation and might be used to stimulate or inhibit the growth of individual cell types.     

Effect of bipolar electrode orientation on local electrogram properties

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Pulmonary manifestations of schistosomiasis

Bilharziosis or schistosomiasis is the third leading endemic parasitic disease in the world, following malaria and ambiasis. More than 300 million individuals are infested. Schistomosomes are blood flukes which live in the perivisceral veins. Clinical signs result from ova migrations. Transmitted by urine and feces, the parasite cycle requires intermediary host, usually fresh water snails. Bilharsiosis is endemic in tropical zones where it is a major public health problem closely correlated with the socio-economic conditions. Liver, intestinal or urinary complications, depending on the species, lead to underestimated morbidity and mortality. Pulmonary lesions are attributed to 3 species: S. haematobium, S. mansoni and S. japonicum. Although the lung is mandatory step in the parasite cycle, pulmonary manifestations are limited. They can be acute or chronic depending on the phase of the cycle, but are the most frequent extradigestive localization for S. mansoni. Morbidity due to chronic manifestations is particularly severe and should be prevented whenever possible.     

Orchidectomy and hormonal therapy of prostate cancer

The objective of this study is to document the use of hormonal therapies in treating prostate cancer in Ontario in the last decade. Drug utilization data were extracted from the Ontario Drug Benefit Program, while surgical orchidectomy rates were calculated from Hospital Medical Records Institute data. The provincial rate of orchidectomy showed a 55% relative increase from 1981 to 1991. There was a 6.4-fold variation in orchidectomy rates among counties in Ontario. As well, the expenditures on new hormonal therapies rose 38-fold between 1985 and 1990, and doubled between 1990 and 1992. There was no consistent relationship between use of orchidectomy and hormonal drug therapy at the county level. We conclude that both forms of hormonal therapy have increased in Ontario. The wide variation in surgical orchidectomy rates observed in Ontario suggests differences in practice styles and possible medical uncertainty. Guidelines for the hormonal therapy of prostate cancer may be a helpful step forward for practitioners and patients.