English term biological

This project is focused on studying the biological effects of low-power RF radiation on the expression and function of mechanosensitive ion channel protein (Piezo-1). To evaluate the effects of long-term exposures, cells were exposed at the frequency of 1800 MHz and power of 17 dBm for a period of 2 and 4 hrs using the transverse electromagnetic (TEM) cell exposure system. To study the effects of short-term RF radiation (10 min), exposures emitted from the mobile phone headset at the frequency of 845 MHz and powers of -15 dBm and -5 dBm were applied to cell cultures.

141p runthenight04 02-02-2023 9 3   Download

The thesis aims to obtain data on freshwater crustacean composition in the water bodies of Phong Nha - Ke Bang National Park. Identify the characteristics of quantity distribution of freshwater crustaceans in the study areas along with the changes of this group in terms of space and climate season. Proposing solutions to conservation of specific and important types of SE in limestone areas of Phong Nha and Quang Binh national parks.

27p xacxuoc4321 11-07-2019 62 5   Download

We report here the direct evidence for the formation of alternative DNA structures in a plasmid DNA, termed pTIR10, containing a 0.23-kb pyrimidine/purine-biased (Pyr/Pur) stretch isolated from the rat genome. Long Pyr/Pur sequences are abundant in eukaryotic genomes, and they may modulate the biological activity of genes and genomes via formation of various types of triplex-related structures. The plasmid DNA in sodium acetate buffer (pH 4.35) was deposited on APS-modified mica, and after drying it was imaged with an atomic force microscope in air. ...

5p system191 01-06-2013 34 3   Download

The case of homologous monomeric c-type and oligomeric b-type crystallins has been described and analyzed in evolutionary terms. Data and hypotheses from molecular genetics and structural investigations converge and suggest a novel three-phase model for the evolutionary history of crystallin-type proteins. In the divergent cascades of monomeric and oligomeric crystallins, a pivotal role was played by alterations in the gene segments encoding the C-terminal extensions and the intermotif or interdomain linker peptides.

9p system191 01-06-2013 41 4   Download

Cytochrome c is widely distributed in bacterial species, from mesophiles to thermophiles, and is one of the best-characterized redox proteins in terms of biogenesis, folding, structure, function, and evolution. Experimental molecular biology techniques (gene cloning and expression) have become applicable to cytochrome c, enabling its engineering and manipulation. Heterologous expression systems for cytochromes c in bacteria, for use in mutagenesis studies, have been established by extensive investigation of the biological process by which the functional structure is formed. ...

7p research12 01-06-2013 32 3   Download

Tyrosinase (monophenol,L-DOPA:oxygen oxidoreductase) was isolated from the ink of the squid,Illex argentinus. Squid tyrosinase, termed ST94, was found to occur as a covalently linked homodimeric protein with a molecular mass of 140.2 kDa containing two copper atoms per a subunit. The tyrosinase activity of ST94 was enhanced by proteolysis with trypsin to form a protein, termed ST94t, with a molecular mass of 127.6 kDa.

13p tumor12 20-04-2013 30 3   Download

Caseins are highly phosphorylated milk proteins assembled in large colloidal structures termed micelles. In the milk of ruminants, as1-casein has been shown to be extensively phosphorylated. In this report we have determined the phosphorylation pattern of humanas1 -casein by a combi-nationofmatrix-assisted laserdesorptionmass spectrometry and amino acid sequence analysis. Three phosphorylation variants were identified. A nonphosphorylated form, a variant phosphorylated at Ser18 and a variant phosphory-lated at Ser18 and Ser26.

5p tumor12 20-04-2013 34 4   Download

Termination of mitochondrial (mt) H-strand transcription in mammalian cells occurs at two distinct sites on the genome. The first site of termination, referred to as mt-TERM occurs beyond the 16 S rRNA gene. However, the second and final site of termination beyond the tRNA Thr gene remains unclear. In this study we have characterized the site of termination of the polycistronic distal gene transcript beyond the D-loop region, immedi-ately upstream of the tRNA Phe gene.

13p tumor12 20-04-2013 43 3   Download

The targeting of proteins to particular subcellular sites is an important principle of the functional organization of cells at themolecular level. In turn, knowledge about the subcellular localizationof aprotein is acharacteristic thatmayprovidea hint as to the function of the protein.

11p tumor12 20-04-2013 36 4   Download

Embryos of the brine shrimp,Artemia franciscana, exhibit remarkable resistance to physiological stress, which is tem-porally correlated with the presence of two proteins, one a small heat shock/a-crystallin protein termed p26 and the other called artemin, of unknown function.Artemin was sequenced previously by Edman degradation, and its rela-tionship to ferritin, an iron storage protein, established.The isolation from anArtemiaexpressed sequence tag library of artemin and ferritin cDNAs extends this work. ...

9p tumor12 20-04-2013 25 4   Download

Primary olfactory neuronal cultures exposed to odorant stimulation have previously exhibited concentration-related effects in terms of intracellular cAMP levels and adenylate cyclase activity [Ronnett, G.V., Parfitt, D.J., Hester, L.D. & Snyder, S.H. (1991)PNAS88, 2366–2369].Maximal sti-mulation occurred for intermediate concentrations, whereas AC activity declined for both low and high odorant con-centrations.We suspected that this behavior might be ascribed to the intrinsic response of the first molecular species concerned by odorant detection, i.e. the olfactory receptor itself....

8p fptmusic 16-04-2013 37 3   Download

One of the most drastic post-translational modification of proteins in eu-karyotic cells is poly(ADP-ribosyl)ation, catalysed by a family enzymes termed poly(ADP-ribose) polymerases (PARPs). In the human genome, 18 different genes have been identified that all encode PARP family members.

14p fptmusic 11-04-2013 52 2   Download

Small heat shock proteins (sHSPs) function as molecular chaperones, pre-venting stress induced aggregation of partially denatured proteins and pro-moting their return to native conformations when favorable conditions pertain. Sequence similarity between sHSPs resides predominately in an internal stretch of residues termed the a-crystallin domain, a region usually flanked by two extensions.

15p awards 06-04-2013 37 3   Download

The 2-hydroxycarboxylate transporter (2HCT) family of secondary trans-porters belongs to a much larger structural class of secondary transporters termed ST3 which contains about 2000 transporters in 32 families. The transporters of the 2HCT family are among the best studied in the class. Here we detect weak sequence similarity between the N- and C-terminal halves of the proteins using a sensitive method which uses a database con-taining the N- and C-terminal halves of all the sequences in ST3 and involves blastsearches of each sequence in the database against the whole database. ...

11p awards 06-04-2013 31 4   Download

We have previously reported the Ras-dependent activation of the mitogen-activated protein kinases p44 and p42, also termed extracellular signal-regulated kinases (ERK)1 and 2 (ERK1⁄2), mediated through Gs-coupled serotonin receptors transiently expressed in human embryonic kidney (HEK) 293 cells. Whereas G i- and Gq-coupled receptors have been shown to activate Ras through the guanine nucleotide exchange factor (GEF) called Ras-GRF1 (CDC25 Mm ) by binding of Ca 2+ ⁄calmodulin to its N-terminal IQ domain, ...

0p awards 06-04-2013 35 3   Download

Recently, a novel plaque-associated protein, collagenous Alzheimer amy-loid plaque component (CLAC), was identified in brains from patients with Alzheimer’s disease. CLAC is derived from a type II transmembrane colla-gen precursor protein, termed CLAC-P (collagen XXV). The biological function and the contribution of CLAC to the pathogenesis of Alzheimer’s disease and plaque formation are unknown.

0p awards 06-04-2013 28 2   Download

Ammonium assimilation inEscherichia coliis regulated through multiple mechanisms (metabolic, signal transduction leading to covalent modification, transcription, and translation), which (in-)directly affect the activities of its two ammonium-assimilating enzymes, i.e. glutamine synthetase (GS) and glutamate dehydrogenase (GDH).

21p awards 06-04-2013 29 4   Download

Although of major impact in terms of biological and environmental haz-ards, interactions of actinide cations with biological molecules are only par-tially understood. Human serum transferrin (Tf) is one of the major iron carriers in charge of iron regulation in the cell cycle and consequently con-tamination by actinide cations is a critical issue of nuclear toxicology. Combined X-ray absorption spectroscopy (XAS) and near infrared absorp-tion spectrometry were used to characterize a new complex between Tf and Np (IV) with the synergistic nitrilotriacetic acid (NTA) anion....

0p awards 06-04-2013 49 3   Download

The TPaand TPbisoforms of the human thromboxane A2 receptor (TP) arise by differential splicing but are under the transcriptional control of two distinct promoters, termed Prm1 and Prm3, respectively (Coyle et al. 2002Eur J Biochem269, 4058–4073). The aim of the current study was to determine the key factors regulating TPbexpression by functionally charac-terizing Prm3, identifying the core promoter and the cis-acting elements regulating basal Prm3 activity.

18p awards 05-04-2013 40 3   Download

Retinoid receptors are ligand-dependent transcription factors belonging to the nuclear receptor superfamily. Retinoic acid (RARa, b, c) and retinoid X (RXRa, b, c) receptors mediate the retinoid/rexinoid signal to the transcriptional machineries by interacting at the first level with coactivators or corepressors, which leads to the recruitment of enzymatically active noncovalent com-plexes at target gene promoters.

10p awards 05-04-2013 33 4   Download