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41.
The study investigates the distribution of chronotypes among alcohol-dependent subjects and the relationship between personality and chronotype. Fifty-eight alcohol-dependent patients and 29 age-matched healthy controls were studied using Ogińska’s Chronotype Questionnaire (ChQ), Eysenck’s Personality Questionnaire – Revised (EPQ-R), Selzer’s Michigan Alcoholism Screening Test (MAST) and a sociodemographic status questionnaire designed by the authors. The alcohol-dependent patients tended to be morning type, based on the morningness–eveningness ChQ scale, with a weakly marked rhythm, based on the distinctness ChQ scale. Preference towards morningness was associated with older age, but no relation between chronotype and severity of alcohol dependence was found. A high amplitude of the rhythm was associated with higher neuroticism. Therefore, despite being in the minority, patients with a distinct circadian rhythm (i.e. with a high amplitude) are at greater risk of mood and anxiety disorders and hence should be given special consideration.  相似文献   
42.
European populations of the white‐tailed eagle Haliaeetus albicilla suffered a drastic decline during the 20th century. In many countries, only a few dozen breeding pairs survived or the species disappeared completely. By today, the populations have recovered, naturally or through restocking (e.g. in Scotland or the Czech Republic). In the Carpathian Basin, which is now a stronghold in southern Europe for the species in the southern part of the distribution range with more than 500 breeding pairs, only about 50 pairs survived the bottleneck. This region provides important wintering places for individuals arriving from different regions of Eurasia. In the present study, we investigated 249 DNA samples from several European countries, using 11 microsatellites and mitochondrial control region sequences (499 bp), to answer two main questions: 1) did the Carpathian Basin population recover through local population expansion or is there a significant gene flow from more distant populations as well? 2) Does the Czech population show signs in its genetic structure of the restocking with birds of unknown origin? Our microsatellite data yielded three genetically separate lineages within Europe: northern, central and southern, the latter being present exclusively in the Carpathian Basin. Sequencing of mitochondrial DNA revealed that there is one haplotype (B12) which is not only exclusive to the Carpathian Basin but it is frequent in this population. Our results suggest that in accordance with the presumably philopatric behaviour of the species, recovery of the Carpathian Basin population was mainly local, but some of the wintering birds coming from the northern and central populations contributed to its genetic composition as well. We detected considerably higher proportions of northern birds within the Czech Republic compared to the neighbouring areas, making it likely that parents of the reintroduced birds came from northern populations.  相似文献   
43.
44.
Resonance Raman (RR) spectra of green fluorescent protein (GFP) model chromophores in solution have been simulated with the CASSCF/MM methodology. Although several reports on vibrational analysis of GFP model chromophores have been recently published, the RR spectra were simulated for the first time in explicit solution with the inclusion of the counterion, as these effects are crucial for unambiguously reproducing the vibrational band assignment in the anionic form of the GFP chromophore. This strategy allows for a one-to-one correspondence of the calculated vibrational modes to the observed RR bands, concerning both the location and intensity pattern. In addition, these simulations were complemented with total energy distribution calculations to aid in the unambiguous assignment of the measured spectra. The current study helps to clarify some of the previous RR bands assignments as well as producing some new assignment for the anionic form of GFP chromophore. The explicit solvent simulations and PCM-based calculations are compared to the measured spectra, and these results demonstrate that explicit solvent simulations provide better agreement with experiment, both in terms of vibrational frequencies and intensity distribution. Figure a Correlation of explicit hydration calculations (CASSCF/6-31G*/MM) for the HBI model chromophore and experimental RR data [21]; slope = 0.982, intercept = 27.210 and regression coefficient = 0.997. b Correlation of implicit PCM calculations (CASSCF/6-31G*) for the HBI model chromophore and experimental RR data [21], slope = 1.017, intercept = −48.838 and regression coefficient = 0.984  相似文献   
45.
The two forms of monoamine oxidase, monoamine oxidase A and monoamine oxidase B, have been associated with imidazoline-binding sites (type 2). Imidazoline ligands saturate the imidazoline-binding sites at nanomolar concentrations, but inhibit monoamine oxidase activity only at micromolar concentrations, suggesting two different binding sites [Ozaita A, Olmos G, Boronat MA, Lizcano JM, Unzeta M & García-Sevilla JA (1997) Br J Pharmacol121, 901-912]. When purified human monoamine oxidase A was used to examine the interaction with the active site, inhibition by guanabenz, 2-(2-benzofuranyl)-2-imidazoline and idazoxan was competitive with kynuramine as substrate, giving K(i) values of 3 microM, 26 microM and 125 microM, respectively. Titration of monoamine oxidase A with imidazoline ligands induced spectral changes that were used to measure the binding affinities for guanabenz (19.3 +/- 3.9 microM) and 2-(2-benzofuranyl)-2-imidazoline (49 +/- 8 microM). Only one type of binding site was detected. Agmatine, a putative endogenous ligand for some imidazoline sites, reduced monoamine oxidase A under anaerobic conditions, indicating that it binds close to the flavin in the active site. Flexible docking studies revealed multiple orientations within the large active site, including orientations close to the flavin that would allow oxidation of agmatine.  相似文献   
46.
This study concentrates on the investigation of energy and environmental benefits for used oil pertaining to its reuse through: (i) recovering the heating value of used oils in a combustion process and (ii) re-refining of used oil to produce fresh lube oil products. Tests were made with the used oil samples by ICP technique and the results were compared with standard requirements. We have found that the problems could successfully be solved through used oil management practices including collection centers, transporters, and processors by providing encouragement and financial support towards the re-refining industry. The novelty and value of our work lies in the conclusion that reformulation of motor oil results in lower levels of hazardous elements in used oils.  相似文献   
47.
We report on a PCR-RFLP procedure for recognising of a silent point mutation of ITGB2 CD18 subunit gene in cattle. Polymorphism screening was performed in a Polish Black-and-White cattle population (n=210). The genotype and allele frequencies were established in the sires and cows. Further research is needed to explain the possible applications of the CD18 silent point mutation as a potential molecular marker for high milk productivity.  相似文献   
48.
A membrane transporter for tryptophan composed of RNA   总被引:2,自引:0,他引:2  
Janas T  Janas T  Yarus M 《RNA (New York, N.Y.)》2004,10(10):1541-1549
We have incorporated an RNA binding site for the biological amino acid tryptophan within an RNA complex with affinity for phospholipid bilayer membranes. The resulting RNA (9:10Trp) creates a selective route through the bilayer for the amino acid. Binding and enhanced tryptophan permeability are nonlinear in RNA concentration, suggesting that RNA aggregation is required for both. Tryptophan permeability saturates with increased concentration, though at approximately 1000-fold greater level than when binding a free aptamer. The RNA (9:10Trp) complex, bound at a mean of two per liposome, halves the activation energy for tryptophan transport (to 46 kJ/mole), specifically increasing tryptophan entry to a maximal velocity of 0.5 sec(-1) per liposome with little or no accompanying increase in general permeability. Individual RNAs turn over tens of thousands of times at high tryptophan concentration. Thus, a specific passive membrane transporter whose properties overlap those of single-molecule transporter proteins, can be made of RNA alone. Permeability changes probably rely on disturbances in lipid conformation as well as on an advantageous low free energy position for tryptophan at the membrane. Other RNA activities may yield other RNA-membrane nanosystems via this route.  相似文献   
49.
Mitochondria are important in the pathophysiology of several neurodegenerative diseases, and mitochondrial production of reactive oxygen species (ROS), membrane depolarization, permeability changes and release of apoptogenic proteins are involved in these processes. Following brain insults, cell death often occurs in discrete regions of the brain, such as the subregions of the hippocampus. To analyse mitochondrial structure and function in such subregions, only small amounts of mitochondria are available. We developed a protocol for flow cytometric analysis of very small samples of isolated brain mitochondria, and analysed mitochondrial swelling and formation of ROS in mitochondria from the CA1 and CA3 regions of the hippocampus. Calcium-induced mitochondrial swelling was measured, and fluorescent probes were used to selectively stain mitochondria (nonyl acridine orange), to measure membrane potential (tetramethylrhodamine-methyl-ester, 1,1',3,3,3',3'-hexamethylindodicarbocyanine-iodide) and to measure production of ROS (2',7'-dichlorodihydrofluorescein-diacetate). We found that formation of ROS and mitochondrial permeability transition pore activation were higher in mitochondria from the CA1 than from the CA3 region, and propose that differences in mitochondrial properties partly underlie the selective vulnerability of the CA1 region to brain insults. We also conclude that flow cytometry is a useful tool to analyse the role of mitochondria in cell death processes.  相似文献   
50.
Popek T  Lis T 《Carbohydrate research》2002,337(9):787-801
2,3:4,5-Di-O-isopropylidene-beta-D-fructopyranose 1-sulfate have been synthesized by treatment of 2,3:4,5-di-O-isopropylidene-beta-D-fructopyranose with pyridine-sulfur trioxide complex. Direct hydrolysis of the isopropylidene group at C-4, C-5 gave 2,3-O-isopropylidene-beta-D-fructopyranose 1-sulfate. The crystal and molecular structures of ammonium (1a) and potassium (1b) salts of diisopropylidene derivative and ammonium (2) salt of monoisopropylidene derivative were determined by X-ray crystallography. Data for 1a and 1b were collected in 120 K and in 150 K for 2. All salts crystallized in P2(1)2(1)2(1) space group. There are three independent anions in asymmetric unit in 1b. Pyranose rings in the diisopropylidene derivative salts studied adopt 2S(0) twist boat conformation, whereas in the monoisopropylidene exists in a slightly distorted chair conformation (4C(1)). A staggered conformation is preferred by the sulfate group as indicated by values of C-(ester)-S-O(terminal) torsion angles: -173.2(4) degrees in 1a, 175.1(6) degrees in anion A of 1b, 170.8(6) degrees in anion C of 1b and 177.9(2) degrees in 2. However, strong interactions such as potassium-oxygen and H-bonds may affect the geometry: in anion B of 1b the value of the torsion angle is 139.4(6) degrees.  相似文献   
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