Linear accelerator therapeutic dose-induced radioactivity dependence.

Dependence between therapeutic dose and activity induced in mammal bones is discussed. This activity leads to gamma ray emission registered by HPGe detector and scintilation probe. Presented results are focused on activation which occurs during emission of 15 and 20 MV photon beams. The purpose is to describe how therapeutic conditions (dose, time of irradiation) influence the induced radioactivity. Preliminary studies of decay rate, calculation of half-life and identification of isotopes involved in this dynamic process are given.

[The usefulness of MIBI scintigraphy for postoperative monitoring of patients with thyroid cancer]. / Przydatnosc scyntygrafii MIBI w monitorowaniu pooperacyjnym chorych na zróznicowanego raka tarczycy.

Metoxyizobutyloizonitrile labelled with technetium 99mTc is a radio-pharmaceutical that was shown to accumulate in benign and cancerous thyroid tissue. As it can be applied without thyroid hormone withdrawal this gave a stimulus to the investigations on its usefulness in diagnostic and follow up procedures for thyroid cancer patients. The goal of this study is to evaluate the efficacy and benefit of 99mTc-MIBI whole body scintigrams in post surgery follow-up of patients with differentiated thyroid cancer. One hundred and twenty eight 99mTc MIBI scintigraphy were performed and evaluated. Sensitivity of MIBI scans was the highest for bone metastases--79%. Good results were also obtained for lymph node metastases (sensitivity--73%, specificity--90%). In case of lung metastases the sensitivity and specificity were 21% and 94% respectively. Sensitivity of detection of clinically apparent recurrent disease in thyroid bed was 70% and specificity of visualization 78%. Results of our study demonstrate that 99mTC-MIBI is valuable tool in follow up of thyroid cancer patients, but can not replace 131I scintygraphy.

[Invasive treatment of recent myocardial infarction. Evaluation of left ventricular function]. / Leczenie inwazyjne swiezego zawalu serca. Ocena funkcji lewej komory.

Hemodynamic parameters of left ventricular function were assessed in 179 patients with acute myocardial infarction, who were treated with intracoronary thrombolysis during first six hours after the onset of chest pain. Some of them were subjected to coronary angioplasty. Patency of the infarct related artery was controlled between the 2nd and 3rd week after acute myocardial infarction concomitant with evaluation of EF and LVEDP. Reperfusion of the infarct related artery was obtained in 121 patients (67.6%) and also significant increase of EF was observed in those patients. EF rose in patients with a patent coronary artery after 2-3 weeks (not significant) in contrast to patients with obstructed coronary artery in whom there was a fall in EF. The rise of EF was more pronounced in patients with reperfusion reached in 3 hours after the onset of infarct pain and without coronary angioplasty. It was shown that LVEDP is not usefull in estimation of left ventricular function.

The effect of ethanol-caffeine interaction on the gastric mucosal barrier.

Potential difference across the stomach wall (PD) is determined by the gastric mucosa electrolyte barrier. The decrease in the PD caused by the "barrier breakers" e.g. aspirin, alcohol and cholic acids is a sensitive index of mucosal damage. We studied the effect of interaction between alcohol and caffeine on the PD in the anesthetized rats. The intragastric administration of 1 ml of 40 vol.% ethanol solution decreased the PD by 39%, of 10 mg of caffeine sodium benzoate by 22% and the simultaneous administration of alcohol and caffeine by 53%. These results indicate that caffeine may enhance the damaging effect of alcohol on the gastric mucosal barrier.