Morphometric analysis of supraoptic neurons of the rat hypothalamic nuclei under conditions of prolonged illumination

The article reviews the results of studies of the morphofunctional state of neurons of the supraoptic nuclei of the rat hypothalamus under conditions of different duration of light regime. Under standard light regime in rats, a diurnal rhythm of morphofunctional activity of supraoptic nucleus neurons with maximum activity during daytime (before 2 p.m.) is recorded. In animals subjected to prolonged light exposure, more pronounced changes in the morphofunctional state of the supraoptic neurons of the hypothalamus at 2 a.m. than at 2 p.m. were established. Thus, the neuronal nucleus area was 94.08 ± 9.55 μm2 and was significantly greater than that in intact animals. The nucleo-cytoplasmic ratio of supraoptic hypothalamic neuron at 2 a.m. was lower than that in intact animals due to a decrease in specific nucleus volume. In comparison with the day period (2 p.m.), before 2 a.m. there was revealed a decrease of the neuron body area of supraoptic nuclei of hypothalamus due to possible decrease of the area of nucleus and nucleolus of cells. This was the reason for the increase in the nucleo-cytoplasmic ratio in the neurons under observation at night, which was 2.51 ± 0.023 units. Constant light regime did not cause inversion of the rhythm of morphofunctional activity of the neurons under study, the maximum values, as in intact animals, occurred in the daytime observation period

UniPROBE, update 2011: expanded content and search tools in the online database of protein-binding microarray data on protein–DNA interactions

The Universal PBM Resource for Oligonucleotide-Binding Evaluation (UniPROBE) database is a centralized repository of information on the DNA-binding preferences of proteins as determined by universal protein-binding microarray (PBM) technology. Each entry for a protein (or protein complex) in UniPROBE provides the quantitative preferences for all possible nucleotide sequence variants (‘words’) of length k (‘k-mers’), as well as position weight matrix (PWM) and graphical sequence logo representations of the k-mer data. In this update, we describe >130% expansion of the database content, incorporation of a protein BLAST (blastp) tool for finding protein sequence matches in UniPROBE, the introduction of UniPROBE accession numbers and additional database enhancements. The UniPROBE database is available at http://uniprobe.org.National Institutes of Health (U.S.) (grant number R01 HG003985

UniPROBE, update 2011: expanded content and search tools in the online database of protein-binding microarray data on protein–DNA interactions

The Universal PBM Resource for Oligonucleotide-Binding Evaluation (UniPROBE) database is a centralized repository of information on the DNA-binding preferences of proteins as determined by universal protein-binding microarray (PBM) technology. Each entry for a protein (or protein complex) in UniPROBE provides the quantitative preferences for all possible nucleotide sequence variants (‘words’) of length k (‘k-mers’), as well as position weight matrix (PWM) and graphical sequence logo representations of the k-mer data. In this update, we describe >130% expansion of the database content, incorporation of a protein BLAST (blastp) tool for finding protein sequence matches in UniPROBE, the introduction of UniPROBE accession numbers and additional database enhancements. The UniPROBE database is available at http://uniprobe.org.National Institutes of Health (U.S.) (grant number R01 HG003985

UniPROBE: an online database of protein binding microarray data on protein–DNA interactions

The UniPROBE (Universal PBM Resource for Oligonucleotide Binding Evaluation) database hosts data generated by universal protein binding microarray (PBM) technology on the in vitro DNA-binding specificities of proteins. This initial release of the UniPROBE database provides a centralized resource for accessing comprehensive PBM data on the preferences of proteins for all possible sequence variants (‘words’) of length k (‘k-mers’), as well as position weight matrix (PWM) and graphical sequence logo representations of the k-mer data. In total, the database hosts DNA-binding data for over 175 nonredundant proteins from a diverse collection of organisms, including the prokaryote Vibrio harveyi, the eukaryotic malarial parasite Plasmodium falciparum, the parasitic Apicomplexan Cryptosporidium parvum, the yeast Saccharomyces cerevisiae, the worm Caenorhabditis elegans, mouse and human. Current web tools include a text-based search, a function for assessing motif similarity between user-entered data and database PWMs, and a function for locating putative binding sites along user-entered nucleotide sequences. The UniPROBE database is available at http://thebrain.bwh.harvard.edu/uniprobe/

Age changes in the tigroid substance of neutrons of the lateral preoptic nucleus of hypothalamus under different light modes

The article presents analysis of the results of the original histochemical studies of tigroid substance of neurons of the lateral preoptic nucleus of  hypothalamus in mature and old rats under the influence of different light modes. In all observations, the tigroid substance was located in the cytoplasm of neurons of the lateral preoptic nucleus of hypothalamus in the form of individual granular formations of different sizes and shapes. The amount of tigroid substance of neurons of the lateral preoptic nucleus of hypothalamus in mature rats is greater than in older rats. At the same time, it should be noted that different experimental conditions significantly affected the amount of tigroid substance in neurons of the lateral preoptic nucleus of hypothalamus in old rats. In particular, under conditions of light deprivation, the optical density of specific histochemical staining for tigroid substance in neurons of the lateral preoptic nucleus of hypothalamus increased significantly (p<0,001), and under conditions of light stimulation, on the contrary, probably decreased (p<0,001)

Pressure influence on excitonic luminescence of CsPbBr3 perovskite

This study investigates the effect of hydrostatic pressure on the luminescence properties of CsPbBr3 single crystals at 12 K. The luminescence at the edge of the band gap reveals a structure attributed to free excitons, phonon replica of the free excitons, and Rashba excitons. Changes in the relative intensity of the free and Rashba excitons were observed with increasing pressure, caused by changes in the probability of nonradiative deexcitation. At pressures around 3 GPa, luminescence completely fades away. The red shift of the energy position of the maximum luminescence of free and Rashba excitons in pressure ranges of 0-1.3 GPa is attributed to the length reduction of Pb-Br bonds in [PbBr6]4- octahedra, while the high-energy shift of the Rashba excitons at pressures above 1.3 GPa is due to [PbBr6]4- octahedra rotation and changes in the Pb-Br_Pb angle.Comment: 14 pages, 11 figure