Radioprotective effects of amifostine (WR-2721) or cystamine on radiation damage and its repair in rats whole body exposed to fission neutrons.

Sulphur containing radioprotective drugs amifostine (gammaphos, WR-2721) or cystamine (disulfide of meracaptoethylamine) of Czechoslovak production were examined in whole body fission neutrons irradiated rats in the thermal column of reactor VVR-S. Using the split-dose technic the first sublethal neutron dose in the range 1-2 Gy was followed by second lethal exposures in the two time intervals (3 or 6 days) using whole body fission neutrons irradiations (3 days interval) or whole body gamma-irradiations (6 days interval) for LD50/30 evaluation within next 30 days survival observation. In other experiments the mean survival time (MST) in days was estimated in different rats group, when animals were whole body fission neutrons irradiated twice with 3-days interval using the total lethal doses of 4 or 5 Gy.

[Cytoprotective effects of amifostine in the treatment of tumors].

An efficient therapy of patients with tumorous diseases should include maximum killing of malignant cells with minimal damage to cells in healthy tissues. Radiotherapy and chemotherapy are frequently associated with a series of undesirable effects. Side effects related to the therapy may unfavorably influence quality of life for a short or long period of time, may cause the need to decrease the dosage or shorten the overall period of treatment or survival of the patient.

Radiation pneumonitis: the model of interstitial edema.

We used the measurement of the thickness of alveolar septa in the lungs in (C57BI/6xDBA/2)F1 mice irradiated locally in the area of the thorax with absorbed doses of 14, 16 and 18 Gy of gamma rays. The thickness of alveolar septa of the pulmonary tissue was measured using a computer image analysis. 24 weeks after irradiation we found a significant increase in the thickness of alveolar septa in direct relation to the dose within a range of 14 to 18 Gy.

[Evaluation of the quality of a decision-making rule in discriminant analysis].

Logistic regression (LR) and concept of the beta-confidence allocation rule were applied to predict the survival of dogs within the radiobiological experiment. The biochemical and haematological investigations in 86 dogs on the 2nd, 5th and 8th day post-external gamma-neutron irradiation (4.8-7.

[Classification of multidimensional observations using linear discriminant functions].

In the present paper the role of linear discriminant analysis is delimitated all along with a range of problems which could be solved using this method in appropriate conditions. The analysis is given of possibilities on how to involve the decrease in number of variables in a model, and how to predict probability of incorrect classification. As an example of application, the prediction of dog survival is calculated in radiobiological experiment on the basis of biochemical and hematological values which were obtained by the 2nd day after the irradiation as well as an error probability was determined.