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.
Knowledge of the patterns in the spatial distribution of species provides valuable information about the factors (resources and environment) that regulate the use of space by animals. Typically, the distribution of litter-dwelling scorpions in Atlantic forests is correlated with the structure of their microhabitats, although to better understand their natural history more studies on the patterns in their use of space are required. Therefore, we investigated the effect of rainfall on the patterns in the spatial distributions and population densities of two sympatric species of scorpion, Tityus (Archaeotityus) pusillus Pocock 1893 and Ananteris mauryi Lourenço 1982 in a fragment of Atlantic Forest in Brazil. The study was carried out during the dry (September) and rainy (June) months. We collected 501 individuals (268 T. (A.) pusillus and 233 A. mauryi) by actively searching at night using UV lanterns. We found that the spatial distribution and population density of T. (A.) pusillus, but not A. mauryi, were significantly affected by rainfall, with T. (A.) pusillus individuals showing a clumped pattern during the rainy month and random distribution in the dry month. We also found a different response in the population densities of the two species, with T. (A.) pusillus but not A. mauryi being affected by rainfall. Our results indicate that, although co-habiting in leaf litter, these species respond differently to rainfall, which affects their spatial distribution and abundance in this habitat., Gabriela Cavalcanti Silva de Gusmão Santos, Welton Dionisio-Da-Silva, João Pedro Souza-Alves, Cleide Maria Ribeiro de Albuquerque, André Felipe de Araujo Lira., and Obsahuje bibliografii
The source-sink relationship is one of major determinants of plant performance. The influence of reproductive sink demand on light-saturated photosynthesis (Pmax), dark respiration (RD), stomatal conductance (gs), intrinsic water-use efficiency (WUEi), contents of soluble sugar (SSC), nitrogen, carbon, and photosynthetic pigments was examined in blueberry (Vaccinium corymbosum L. cv. ‘Brigitta’) during the final stage of rapid fruit growth. Measurements were performed three times per day on developed, sun-exposed leaves of girdled shoots with 0.1, 1, and 10 fruit per leaf (0.1F:L, 1F:L, and 10F:L, respectively) and nongirdled shoots bearing one fruit per leaf (NG). Girdling and lower fruit amount induced lower Pmax, gs, N, and total chlorophyll (Chl) and higher WUEi, SSC, RD, Chl a/b ratio and carotenoids-to-chlorophylls ratio (Car/Chl) for the 1F:L and 0.1F:L treatments. The impact of girdling was counterbalanced by 10F:L, with NG and 10F:L having similar values. Variables other than Pmax, RD, gs, WUEi, and SSC were unaffected throughout the course of the day. Pmax and gs decreased during the course of the day, but gs decreased more than Pmax in the afternoon, while WUEi was increasing in almost all treatments. SSC increased from the morning until afternoon, whereas RD peaked at noon regardless of the treatment. Generally, Pmax was closely and negatively correlated to SSC, indicating that sugar-sensing mechanisms played an important role in regulation of blueberry leaf photosynthesis. With respect to treatments, Pmax and N content were positively related, while RD was not associated to substrate availability. The enhanced Car/Chl ratio showed a higher photoprotection under the lower sink demand. Changes in the source-sink relationship in 'Brigitta' blueberry led to a rearrangement of physiological and structural leaf traits which allowed adjusting the daily balance between carbon assimilation and absorbed light energy., E. Jorquera-Fontena, M. Alberdi, M. Reyes-Díaz, N. Franck., and Obsahuje bibliografii