Another article in this issue, Space Shuttles and their contribution, provides an overview of the Space Shuttle Program (officially called Space Transportation System - STS), which the U.S. established in the late 1960s. The program commenced on April 12, 1981, with the launching of Columbia STS-1 - the first shuttle orbital flight - and concluded with its last mission, STS-135 flown by Atlantis in July 2011, which retired the final shuttle in the fleet. The Space Shuttle program formally ended on August 31, 2011. and František Fárník.
There is one feature common to most types of cancer - profound changes in their cellular metabolism that accommodate the high requirements for fast growth and cell division. This change brings about many advantages to the transformed cell and it is also indispensable for its survival and proliferation. This review describes the differences in metabolism between normal and cancerous cells and outlines strategies that could exploit these differences as tools for oncological treatment. and Věra Slaninová, Alena Krejčí.
Raloxifen is a selective estrogen receptor modulator which prevents bone loss in ovariectomized female mice in a fashion similar to estrogens. Since testosterone-deficient male mice also lose bone mass, we were interested in testing the effects of raloxifen on bones in intact and castrated male mice. Bone density was significantly reduced in castrated animals (1.36±0.04 g/ml) as compared to intact animals (1.42±0.03 g/ml) (p<0.01). When castrated mice with extraordinarily low concentrations of testosterone and with reduced weight of seminal vesicles were treated with raloxifen, the changes in bone density and bone minerals resulting from castration (1.36±0.04 g/ml) were entirely prevented (1.40±0.01 g/ml). Cortical bone was lost in orchidectomized mice, and this decrease in cortical thickness of the femur was prevented by raloxifen administration. Raloxifen in a dose used in humans for treatment of osteoporosis decreased the weight of seminal vesicles, an organ which is highly sensitive to the androgenic effect, decreased the concentration of testosterone (12.5±2.8 μmol/l) (p<0.01) but not to the same level as in the case of castrated animals (0.6±0.3 μmol/l), and did not have any effect on bone density or mineral content in intact mice. The results of the present study may thus be interpreted as supporting the hypothesis that raloxifen is an effective agent against the deleterious effects of castration-induced osteopenia in male mice and also support the hypothesis that estrogens may have physiological skeletal effects in male mice., P. D. Broulík, K. Broulíková., and Obsahuje bibliografii a bibliografické odkazy