Search results for "ethology"

Synthesis of GABAA receptor agonists and evaluation of their alpha-subunit selectivity and orientation in the GABA binding site.

2008

Drugs used to treat various disorders target GABA A receptors. To develop alpha subunit selective compounds, we synthesized 5-(4-piperidyl)-3-isoxazolol (4-PIOL) derivatives. The 3-isoxazolol moiety was substituted by 1,3,5-oxadiazol-2-one, 1,3,5-oxadiazol-2-thione, and substituted 1,2,4-triazol-3-ol heterocycles with modifications to the basic piperidine substituent as well as substituents without basic nitrogen. Compounds were screened by [(3)H]muscimol binding and in patch-clamp experiments with heterologously expressed GABA A alpha ibeta 3gamma 2 receptors (i = 1-6). The effects of 5-aminomethyl-3 H-[1,3,4]oxadiazol-2-one 5d were comparable to GABA for all alpha subunit isoforms. 5-pipe…

Jararhagin-derived RKKH Peptides Induce Structural Changes in α1I Domain of Human Integrin α1β1

2003

Integrin alpha(1)beta(1) is one of four collagen-binding integrins in humans. Collagens bind to the alphaI domain and in the case of alpha(2)I collagen binding is competitively inhibited by peptides containing the RKKH sequence and derived from the metalloproteinase jararhagin of snake venom from Bothrops jararaca. In alpha(2)I, these peptides bind near the metal ion-dependent adhesion site (MIDAS), where a collagen (I)-like peptide is known to bind; magnesium is required for binding. Published structures of the ligand-bound "open" conformation of alpha(2)I differs significantly from the "closed" conformation seen in the structure of apo-alpha(2)I near MIDAS. Here we show that two peptides,…

Conformational investigation of alpha,beta-dehydropeptides. XIII. Conformational properties of N-acetyl-alpha,beta-dehydrovaline N',N'-dimethylamide.

2004

The crystal structure of Ac-DeltaVal-NMe(2) (DeltaVal = alpha,beta-dehydrovaline) was determined by X-ray crystallography. The found angles phi = -60 degrees and psi = 125 degrees correspond exactly to the respective values of the (i + 1)th residue in idealised beta-turn II/VIa. Ab initio/DFT studies revealed that the molecule adopts the angle psi restricted only to about |130 degrees | and very readily attains the angle phi = about -50 degrees. This is in line with its solid-state conformation. Taken together, these data suggest that the DeltaVal residue combined with a C-terminal tertiary amide is a good candidate at the (i + 1)th position in a type II/VIa beta-turn.

Combined use of 13C chemical shift and 1H alpha-13C alpha heteronuclear NOE data in monitoring a protein NMR structure refinement.

1995

A large portion of the 13C resonance assignments for murine epidermal growth factor (mEGF) at pH 3.1 and 28 degrees C has been determined at natural isotope abundance. Sequence-specific 13C assignments are reported for 100% of the assignable C alpha, 96% of the C beta, 86% of the aromatic and 70% of the remaining peripheral aliphatic resonances of mEGF. A good correlation was observed between experimental and back-calculated C alpha chemical shifts for regions of regular beta-sheet structure. These assignments also provide the basis for interpreting 1H alpha-13C alpha heteronuclear NOE (HNOE) values in mEGF at natural isotope abundance. Some of the backbone polypeptide segments with high in…

Zoology and Animal Ecology: Abstract book : 3 February 2022, Nature House University of Latvia, Riga, Latvia

2022

Zoology and Animal Ecology: Abstract book : 25 January 2023, Nature House University of Latvia, Riga, Latvia

2023

The Zoology and Animal Ecology section of the conference covers a broad range of topics, ranging from the distribution of animal species and the different aspects of species' interactions with the environment to animal genetics and physiology, including behaviour, conservation and other topics where study objects are animals.

2015

The execution of unilateral hand contractions before performance has been reported to produce behavioral aftereffects in various tasks. These effects have been regularly attributed to an induced shift in activation asymmetry to the contralateral hemisphere produced by the contractions. An alternative explanation proposes a generalized state of reduced bilateral cortical activity following unilateral hand contractions. The current experiment contrasted the above explanation models and tested the state of cortical activity after the termination of unilateral hand contractions. Twenty right-handed participants performed hand contractions in two blocks, one for each hand. Using electroencephalo…

Ablation of interleukin-4 receptor alpha in macrophages ameliorates fibrotic NASH phenotype in murine nonalcoholic steatohepatitis

2018

Systematic measurements of proton- and alpha-capture cross sections relevant to the modelling of the p process

2005

Several in-beam cross section measurements of proton- as well as α -capture reactions in the Se-Sb region have been carried out to obtain global input parameters for Hauser-Feshbach (HF) calculations. In total, 20 (p, γ ) and 7 ( α , γ ) reactions were measured. We compare some of these results with Hauser-Feshbach calculations using various optical model potentials and nuclear level densities.

Hepatocellular carcinoma: comparison of two different periods at the same center.

2010

Aims: To analyze the main etiological factors and some clinical characteristics of patients with HCC at diagnosis and to compare them with those we described ten years ago. Methods: 179 patients were included in Group 1, while 132 patients were included in Group 2. For all patients age, sex, serum markers of hepatitis B and C viruses, alcohol consumption, serum alpha feto-protein (AFP) levels and the main liver function parameters at HCC diagnosis were recorded. Results: Mean age was 66.0 years for Group 1 and 69.0 for Group 2 (P=0.005). HCV was responsible for 80.3% of HCC cases in Group 2 versus 72% in Group 1 (P=0.005). HBV alone and co-infection of HCV+HBV decreased, but not significant…