Differences in permeability of preterm and term fetal membranes to calcium ions - Preliminary report.

The metabolic activity of amniochorion contributes to the control of activation of labor-type uterine contractions. The study presents an experimental model of transport of calcium ions across the human amniochorion sampled directly after cesarean section in patients delivering both at term and prematurely. Transmembrane transport of calcium ions was lower in preterm vs.

Light-induced differences in conformational dynamics of the circadian clock regulator VIVID.

The LOV (light-oxygen-voltage) domain protein VIVID (VVD) is a negative regulator of the circadian transcription factor White Collar Complex and controls light response and photoadaptation in Neurospora. Blue light converts VIVID from the dark state into the light state (VVDL) with concomitant homodimerization. Upon return to low-light conditions, VVD very slowly reverts back into the monomeric dark state (VVDD).

Circadian conformational change of the Neurospora clock protein FREQUENCY triggered by clustered hyperphosphorylation of a basic domain.

In the course of a day, the Neurospora clock protein FREQUENCY (FRQ) is progressively phosphorylated at up to 113 sites and eventually degraded. Phosphorylation and degradation are crucial for circadian time keeping, but it is not known how phosphorylation of a large number of sites correlates with circadian degradation of FRQ. We show that two amphipathic motifs in FRQ interact over a long distance, bringing the positively charged N-terminal portion in spatial proximity to the negatively charged middle and C-terminal portion of FRQ.

Photoadaptation in Neurospora by competitive interaction of activating and inhibitory LOV domains.

Light responses and photoadaptation of Neurospora depend on the photosensory light-oxygen-voltage (LOV) domains of the circadian transcription factor White Collar Complex (WCC) and its negative regulator VIVID (VVD). We found that light triggers LOV-mediated dimerization of the WCC. The activated WCC induces expression of VVD, which then disrupts and inactivates the WCC homodimers by the competitive formation of WCC-VVD heterodimers, leading to photoadaptation.

[Tick borne encephalitis and enviromental changes].

Currently observed markedly increased incidence of various tick borne diseases in many parts of Europe is due to documented climatic changes as well anthropogenic influence on habitat structure. One of the analyzed factors is tendency to increase of the spring temperatures, especially in the third decade of the April. Such conditions (spring temperatures above 7-10 degrees C) let the nymphs and larvae of Ixodes ricinus to feed simultaneously on rodents.

[The lymph nodes of the fallow deer (Dama dama L., 1758)].

In the present study the topographic anatomy of the lymph nodes of fallow deer is described in detail. The Nl. axillaris proprius is absent.