“The influence of light and temperature on the cylindrospe


“The influence of light and temperature on the cylindrospermopsin (CYN) production of two Aphanizomenon flos-aquae strains, isolated from Mizoribine in vitro North-eastern German lakes, was investigated with semi-continuously growing cultures. A light gradient from 10 to 60 mu E m(-2) s(-1) in combination with temperatures of 16, 20, and 25 degrees C was tested.\n\nCYN concentrations varied by a maximum factor of 2.7 in strain 10E9 with a significant

decrease with increasing temperature. Strain 22D11 showed less pronounced changes, i.e. by a factor of 1.6, and without clear relationship to temperature.\n\nReaction patterns of CYN production to changing light intensities are different at different temperatures. In both strains CYN concentrations increase significantly see more at 20 degrees C between 10 and 60 mu E m(-2) s(-1), whereas they decrease significantly at 25 degrees C in the same light gradient. The amount of synthesised CYN is not reflected

by growth rates of the strains in a uniform manner. Nonetheless several temperature-light combinations which constitute physiological stress seem to trigger CYN production and particularly CYN release from cells. The lowest growth rate observed at 16 degrees C and 60 mu E m(-2) s(-1) of strain 22D11 may reflect photoinhibition due to the lower temperature and related limited CO(2)-fixation. Under these conditions, extracellular CYN concentrations increased to 58% of total CYN, while the share of extracellular CYN of all other light and temperature regimes was 11-26%. From the results and the experimental design we conclude an active release of the toxin into medium to be more likely than mere leakage from cells. (C) 2008 Elsevier B.V. All rights reserved.”
“White adipose tissue, previously regarded as a passive Smad inhibitor lipid storage site, is now viewed

as a dynamic tissue. It has the capacity to actively communicate by sending and receiving different types of signals. An overview of these signals, the external modulators that affect adipose tissue and the secreted signaling molecules, the adipokines, is presented. The secretory function is highlighted in relation to energy metabolism, inflammation and the extracellular matrix and placed in the context of adipose tissue biology. We observe that the endocrine function of adipocytes receives much attention, while its paracrine and autocrine functions are underestimated. Also, we provide examples that species specificity should not be neglected. We conclude that adipose tissue primarily is an energy storage organ, well supported by its secretory function.”
“Like tumor metastases, endometriotic implants require neovascularization to proliferate and invade into ectopic sites within the host. Endometrial tissue, with its robust stem cell populations and remarkable regenerative capabilities, is a rich source of proangiogenic factors.

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