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51.
A novel series of arylsulfonamide derivatives of (aryloxy)propyl piperidines was designed to obtain potent 5-HT7R antagonists. Among the compounds evaluated herein, 3-chloro-N-{1-[3-(1,1-biphenyl-2-yloxy)2-hydroxypropyl]piperidin-4-yl}benzenesulfonamide (25) exhibited antagonistic properties at 5-HT7R and showed selectivity over selected serotoninergic and dopaminergic receptors, as well as over serotonin, noradrenaline and dopamine transporters. Compound 25 demonstrated significant antidepressant-like activity in the forced swim test (0.625–2.5 mg/kg, i.p.) and in the tail suspension test (1.25 mg/kg, i.p.), augmented the antidepressant effect of inactive doses of escitalopram (selective serotonin reuptake inhibitor) and bupropion (dopamine reuptake inhibitor) in the FST in mice, and similarly to SB-269970, exerted pro-cognitive properties in the novel object recognition task in cognitively unimpaired conditions in rats (0.3 mg/kg, i.p.). Such an extended pharmacological profile, especially the augmentation effect of the identified 5-HT7R antagonist on SSRI activity, seems promising regarding the complexity of affective disorders and potentially improved outcomes, including mnemonic performance.  相似文献   
52.
IgA, IgG and IgM antibodies against Yersinia Yop proteins, Yersinia LPS and Salmonella LPS from different serogroups were determined by enzyme-linked immunosorbent assay (ELISA) in a 885 serum samples and 92 synovial fluids. The control group consisted of 200 healthy blood donors. Compared with control subjects, patients with arthritis showed significantly increased titres of antibodies against Yersinia Yop, Yersinia LPS and Salmonella LPS appropriately in 21.7%, 44.0% and 56.0% serum samples. The prevalence of positive antibody levels was highest in Yersinia serogroup O3 and Salmonella serogroup B and D antibodies. The IgA titres were found to be much higher in adults than in children and youngsters but IgM titres consequently decreased with age. Investigation of synovial fluids obtained from patients with arthritis showed that Yersinia and Salmonella antibodies in synovial fluid mirror those in serum by concentration, by specificity and by distribution in classes.  相似文献   
53.
Summary 1. The effect of lead (in vivo) on the uptake of GABA, dopamine, and histidine as a precursor of histamine in synaptosomes obtained from chronically lead-treated rats was studied.2. Lead decreased the uptake of GABA, increased the uptake of dopamine, and did not change the uptake of histidine. These effects were independent of calcium concentration.3. Lead administration to the rat changed the morphology of the synaptosomes, as manifested in the decreased number of synaptic vesicles and disturbed mitochondrial structure.4. The results suggest the existence of several mechanisms of lead toxicity on uptake, related to individual neurotransmitters, which are not necessarily connected with a Pb2+/Ca2+ interaction.  相似文献   
54.
Since Svf1 is phosphoprotein, we investigated whether it was a substrate for protein kinase CK2. According to the amino acid sequence Svf1 harbours 20 putative CK2 phosphorylation sites. Here, we have reported cloning, overexpression, purification and characterization of yeast Svf1 as a substrate for three forms of yeast CK2. Svf1 serves as a substrate for both the recombinant CK2α (K m 0.35 μM) and CK2α′ (K m 0.18 μM) as well as CK2 holoenzyme (K m 1.1 μM). Different K m values argue that CK2β(β′) subunit has an inhibitory effect on the activity of both CK2α and CK2α′ towards surviving factor Svf1. Reconstitution of α′2ββ′ isoform of CK2 holoenzyme shows that β/β′ subunits have regulatory effect depending on the kind of CK2 catalytic subunit. This effect was not observed in the case of α2ββ′ isoform, which may be due to interaction between Svf1 and regulatory CK2β subunit (shown by co-immunoprecipitation experiments). Interactions between CK2 subunits and Svf1 protein may have influence on ATP as well as ATP-competitive inhibitors (TBBt and TBBz) binding. CK2 phosphorylates up to six serine residues in highly acidic peptide K199EVIPESDEEESSADEDDNEDEDEESGDSEEESGSEEESDSEEVEITYED248 of the Svf1 protein in vitro. Presented data may help to elucidate the role of protein kinase CK2 and Svf1 in the regulation of cell survival pathways.  相似文献   
55.
This paper is the first geomycological report regarding the fungal communities on rock surfaces in the Demänovská Ice Cave and the Demänovská Cave of Liberty, Slovakia. The samples were collected in June 2014 from five locations from inside both the caves by using sterile swabs wetted with physiological saline (0.85% NaCl). The density of epilithic fungi isolated from the Demänovská Ice Cave ranged from 238.7 to 575.1 CFU (colony-forming units) per m2 of the rock surface, and from the Demänovská Cave of Liberty ranged from 88.6 to 347 CFU. Seventeen different free-living culturable fungi (15 filamentous fungi, one yeast, and one yeast-like fungus) were isolated from the rock surfaces of both caves. Generally, Cladosporium cladosporioides and Aspergillus flavus were the most frequently cultured species from the Demänovská Ice Cave and the Demänovská Cave of Liberty, respectively. Free-living fungi found on the rock surfaces of both caves can lead to their slow biodegradation.  相似文献   
56.
57.
Aim This study investigated whether habitat fragmentation at the landscape level influences patch occupancy and abundance of the black‐headed gull, Chroicocephalus ridibundus, and whether the response of the species to environmental factors is consistent across replicated landscape plots. Location Water bodies (habitat patches) in southern Poland. Methods Surveys were conducted in two landscape types (four plots in each): (1) more‐fragmented landscape, in which habitat patches were small (mean size 2.2–6.2 ha) and far apart (mean distance 2.5–3.1 km); and (2) less‐fragmented landscape, in which habitat patches were large (mean size 9.2–16.5 ha) and separated by short distances (mean 0.9–1.4 km). Observations were performed twice in 284 potential habitat patches during the 2007 breeding season. Results Colonies were significantly more frequent and larger in the less‐fragmented landscapes than in the more‐fragmented ones. Probability of patch occupancy and number of breeding birds were positively related with patch size and these relationships were especially strong in the more‐fragmented landscapes. In the less‐fragmented landscapes, the occurrence of black‐headed gulls was negatively related to the distance to the nearest local population, but in the more‐fragmented landscapes such a relationship was not detected. As distance to the nearest habitat patch increased, the probability of the patch occupancy decreased in the more‐fragmented landscapes. Moreover, abundance was negatively influenced by distance to the nearest habitat patch, especially strongly in more‐fragmented landscapes. Proximity of corridors (rivers) positively influenced the occupation of patches regardless of landscape type. The number of islets positively influenced occupancy and abundance of local populations, and this relationship was stronger in the more‐fragmented landscapes. Main conclusions Our results are in agreement with predictions from metapopulation theory and are the first evidence that populations of black‐headed gulls may have a metapopulation structure. However, patch occupancy and abundance were differentially affected by explanatory variables in the more‐fragmented landscapes than in the less‐fragmented ones. This implies that it is impossible to derive, a priori, predictions about presence/abundance patterns based on only a single landscape.  相似文献   
58.
The involvement of both apolipoprotein E (apoE) and mitochondria in lipid metabolism is widely recognized, however there is surprisingly scarce data about the putative mitochondrial action(s) of this protein. The aim of the study was to screen the alterations in liver mitochondrial proteome caused by apoE deficiency. We applied 2DE-LC-MS/MS methodology to investigate the changes in liver mitochondrial protein expression in 6-months old apoE(-/-) mice as compared to C57BL/6J controls. ApoE(-/-), but not C57BL/6J mice developed visible atherosclerotic changes in aorta and mild, diffuse steatosis of the liver. Collectively, 18 differentially expressed proteins were identified in mitochondria, related to apoptosis, antioxidant and detoxifying mechanisms of mitochondria, as well as lipid metabolism and transport. In conclusion, differential proteomic approach revealed several lines of proteomic evidence that mitochondrial function in the liver of apoE(-/-) mice could be altered as a result of overlapping of pathological and compensatory changes in expression of proteins.  相似文献   
59.
We discuss some aspects of mathematical modelling relevant to the dynamics of insect flight in the context of insect-like flapping-wing micro air vehicles (MAVs). MAVs are small flying vehicles developed to reconno?tre in confined spaces. This requires power-efficient, highly-manoeuvrable, low-speed flight with stable hover. All of these attributes are present in insect flight and hence the focus on reproducing the functionality of insect flight by engineering means. Empirical research on insect flight dynamics is limited by experimental difficulties. Force and moment measurements require tethering the animal whose behaviour may then differ from free flight. The measurements are made when the insect actively tries to control its flight, so that its open-loop dynamics cannot be observed. Finally, investigation of the sensory-motor system responsible for flight is even more challenging. Despite these difficulties, much empirical progress has been made recently. Further progress, especially in the context of MAVs, can be achieved by the complementary information derived from appropriate mathematical modelling. The focus here is on a means of computing the data not easily available from experiments and also on making mathematical predictions to suggest new experiments. We consider two aspects of mathematical modelling for insect flight dynamics. The first one is theoretical (computational), as opposed to empirical, generation of the aerodynamic data required for the six-degrees-of-freedom equations of motion. For this purpose we first explain insect wing kinematics and the salient features of the corresponding flow. In this context, we show that aerodynamic modelling is a feasible option for certain flight regimes, focusing on a successful example of modelling hover. Such modelling progresses from the first principles of fluid mechanics, but relies on simplifications justified by the known flow phenomenology and/or geometric and kinematic symmetries. This is relevant to six types of fundamental manoeuvres, which we define as those flight conditions for which only one component of the translational and rotational body velocities is nonzero and constant. The second aspect of mathematical modelling for insect flight dynamics addressed here deals with the periodic character of the aerodynamic force and moment production. This leads to consideration of the types of solutions of nonlinear equations forced by nonlinear oscillations. In particular, the mechanism of synchronization seems relevant and should be investigated further.  相似文献   
60.
Conformations of two pairs of dehydropeptides with the opposite configuration of the ΔPhe residue, Boc‐Gly‐ΔZPhe‐Gly‐Phe‐OMe ( Z‐ OMe ), Boc‐Gly‐ΔEPhe‐Gly‐Phe‐OMe ( E‐ OMe ), Boc‐Gly‐ΔZPhe‐Gly‐Phe‐p‐NA ( Z‐p‐ NA ), and Boc‐Gly‐ΔEPhe‐Gly‐Phe‐p‐NA ( E‐p‐ NA ) were compared on the basis of CD and NMR studies in MeOH, trifluoroethanol (TFE), MeCN, chloroform, and dimethylsulfoxide (DMSO). The CD results were used as the additional input data for the NMR‐based determination of the detailed solution conformations of the peptides. It was found that E‐ OMe is unordered and Z‐ OMe , Z‐p‐ NA , and E‐p‐ NA adopt the β‐turn conformation. There are two overlapping β‐turns in each of those peptides: type II and type III′ in Z‐ OMe and Z‐p‐ NA , and two type III in E‐p‐ NA . The ordered structure‐inducing properties of ΔZPhe and ΔEPhe in the peptides studied depend on the C‐terminal blocking group. In methyl esters, the ΔZPhe residue is a strong inducer of ordered conformations whereas the ΔEPhe one has no such properties. In p‐nitroanilides, both isomers of ΔPhe cause the peptides to adopt ordered structures to a similar extent. © 2010 Wiley Periodicals, Inc. Biopolymers 93: 1055–1064, 2010. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com  相似文献   
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