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31.
Hasslöf P. Granqvist L. Stecksén-Blicks C. Twetman S. 《Probiotics and antimicrobial proteins》2022,14(2):384-390
Probiotics and Antimicrobial Proteins - The aim of this study was to evaluate the effect of drops containing probiotic bacteria on the recurrence of dental caries in preschool children. The study... 相似文献
32.
The effect of polyelectrolyte cation specificity, charge density, and conformation on the interaction between furcelleran, kappa, iota, and lambda-carrageenan, respectively, and amitriptyline, an amphiphilic cationic drug molecule, was studied by means of a dialysis equilibrium technique. The carrageenans used in this study-furcelleran, kappa, iota, and lambda-carrageenan-had a charge density corresponding to 0.69, 0.92, 1.53, and 2.07 sulfate groups per disaccharide. In general, the binding isotherms followed the order Li(+) < Na(+) < N(CH3)(4)(+) < K(+) < or = Cs(+) approximately Rb(+), i.e., the binding isotherms were shifted to higher concentrations of free amphiphile according to the sequence indicated. This affinity sequence correlates well with that found for the dextran sulfate-amitriptyline system (A. Hugerth and L.-O. Sundel?f, Langmuir 2000, 16, 313-317). The factor determining the critical aggregation concentration in the presence of Na(+) compared to K(+) was found to be as follows: the flexibility (conformation) in the case of the lower charged carrageenans, i.e., furcelleran and kappa-carrageenan, charge density for iota-carrageenan, and in the lambda-carrageenan case the difference in the ROSO(3)(-)-alkali ion specificity. 相似文献
33.
A method for calculating the curves of DNA transition from linear to condensed state upon binding of condensing ligands has been developed. The character of the transition and ligand concentration necessary for condensation have been shown to be governed by the length of DNA molecule, energy and stoichiometry parameters of DNA-ligand complex (equilibrium constant between linear and condensed form in the absence of ligands, constants for ligand binding to linear and condensed forms, the number of base pairs covered by one ligand, etc.). The results of the calculations indicate that only slight difference in the free energies of these states in free DNA (less than 6 cal/mole(bp) for DNA of 500 bp long) is sufficient for the existence of stable linear state in the absence of ligands (in free DNA) and the formation of stable condensed state upon complexation. 相似文献
34.
Cotecchia S Stanasila L Diviani D Björklöf K Rossier O Fanelli F 《Biology of the cell / under the auspices of the European Cell Biology Organization》2004,96(5):327-333
The aim of a large number of studies on G protein-coupled receptors was centered on understanding the structural basis of their main functional properties. Here, we will briefly review the results obtained on the alpha1-adrenergic receptor subtypes belonging to the rhodopsin-like family of receptors. These findings contribute, on the one hand, to further understand the molecular basis of adrenergic transmission and, on the other, to provide some generalities on the structure-functional relationship of G protein-coupled receptors. 相似文献
35.
In order to study the genetic structure of the Adriatic shared stock of red mullet (Mullus barbatus), we developed a set of dinucleotide microsatellite markers. A dinucleotide-enriched genomic library was obtained, and 6 polymorphic dinucleotide loci were successfully optimized. The markers showed high expected heterozygosity (from 0.68 to 0.92) and allele number (from 12 to 33); thus they appear to be suitable for detecting genetic differences in the population of red mullet. Four Adriatic samples were subsequently analyzed for microsatellite variation, and the results showed subtle but statistically significant genetic differentiation, indicating that the Adriatic red mullet may group into local, genetically isolated populations. No correlation between geographic distance and genetic differentiation was observed. In addition, the evidence of recent bottlenecks in the Adriatic samples indicates that the observed population subdivision might reflect random local allelic variations, generated by reproductive success, survival rates, or fishing pressure. 相似文献
36.
Ethylhydroxyethyl cellulose (EHEC) of three different viscosity classes (EHEC I, II, and III) was analyzed by programmed cross-flow asymmetrical flow field-flow fractionation coupled to multiangle light scattering and refractive index detectors to determine their size and molar mass distribution. Two size populations were detected in the two lower viscosity classes, EHEC I and II, one high molar mass and one ultrahigh molar mass (UHM). The two covered molar masses from 10(4) up to 10(9) g X mol(-1). The highest viscosity class EHEC III was less size-dispersed covering molar masses from 5 x 10(5) to 5 x 10(7) g.mol(-1). Filtering of the EHEC II solution removed small amounts of compact UHM material. Enzyme treatments were performed on EHEC II to further characterize it. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and anion ion-exchange chromatography coupled to pulsed amperometric detection showed that the UHM component contained EHEC. 相似文献
37.
Lanne B Potthast F Höglund A Brockenhuus von Löwenhielm H Nyström AC Nilsson F Dahllöf B 《Proteomics》2001,1(7):819-828
Adipose tissue imposes problems in two-dimensional (2-D) analysis due to its extremely high content of fat. To improve protein separation detergents and chaotropes were varied in the IEF step. The most important factor for obtaining distinct spots in the 2-D gel was whether thiourea was included or not. Many high molecular weight spots became resolved by using thiourea, while no spots disappeared or showed inferior characteristics, thus approximately twice as many spots were possible to quantify. Hydrophobic indices were compared for a set of proteins that gave rise to sharper spots with proteins that were not improved on the use of thiourea. The comparison did not give any statistically significant difference between the two groups of proteins. One of the effects obtained by inclusion of thiourea was that the dominating protein, serum albumin, appeared as more condensed spots allowing other minor proteins to be detected. This work resulted in a protocol which greatly enhances the resolution of proteins in adipose tissue. A 2-D map of mouse white adipose tissue from epididymal fat pads was constructed in which 140 spots were identified by mass spectrometry. This work lays the ground for our further studies on white adipose tissue in metabolic diseases such as obesity and dyslipidemia. 相似文献
38.
Ljung B Bamberg K Dahllöf B Kjellstedt A Oakes ND Ostling J Svensson L Camejo G 《Journal of lipid research》2002,43(11):1855-1863
Abnormalities in fatty acid (FA) metabolism underlie the development of insulin resistance and alterations in glucose metabolism, features characteristic of the metabolic syndrome and type 2 diabetes that can result in an increased risk of cardiovascular disease. We present pharmacodynamic effects of AZ 242, a novel peroxisome proliferator activated receptor (PPAR)alpha/gamma agonist. AZ 242 dose-dependently reduced the hypertriglyceridemia, hyperinsulinemia, and hyperglycemia of ob/ob diabetic mice. Euglycemic hyperinsulinemic clamp studies showed that treatment with AZ 242 (1 micromol/kg/d) restored insulin sensitivity of obese Zucker rats and decreased insulin secretion. In vitro, in reporter gene assays, AZ 242 activated human PPARalpha and PPARgamma with EC(50) in the micro molar range. It also induced differentiation in 3T3-L1 cells, an established PPARgamma effect, and caused up-regulation of liver fatty acid binding protein in HepG-2 cells, a PPARalpha-mediated effect. PPARalpha-mediated effects of AZ 242 in vivo were documented by induction of hepatic cytochrome P 450-4A in mice. The results indicate that the dual PPARalpha/gamma agonism of AZ 242 reduces insulin resistance and has beneficial effects on FA and glucose metabolism. This effect profile could provide a suitable therapeutic approach to the treatment of type 2 diabetes, metabolic syndrome, and associated vascular risk factors. 相似文献
39.
Shoot-derived auxin is essential for early lateral root emergence in Arabidopsis seedlings 总被引:2,自引:0,他引:2
Bhalerao RP Eklöf J Ljung K Marchant A Bennett M Sandberg G 《The Plant journal : for cell and molecular biology》2002,29(3):325-332
Lateral root formation is profoundly affected by auxins. Here we present data which indicate that light influences the formation of indole-3-acetic acid (IAA) in germinating Arabidopsis seedlings. IAA transported from the developing leaves to the root system is detectable as a short-lived pulse in the roots and is required for the emergence of the lateral root primordia (LRP) during early seedling development. LRP emergence is inhibited by the removal of apical tissues prior to detection of the IAA pulse in the root, but this treatment has minimal effects on LRP initiation. Our results identify the first developing true leaves as the most likely source for the IAA required for the first emergence of the LRP, as removal of cotyledons has only a minor effect on LRP emergence in contrast to removal of the leaves. A basipetal IAA concentration gradient with high levels of IAA in the root tip appears to control LRP initiation, in contrast to their emergence. A significant increase in the ability of the root system to synthesize IAA is observed 10 days after germination, and this in turn is reflected in the reduced dependence of the lateral root emergence on aerial tissue-derived auxin at this stage. We propose a model for lateral root formation during early seedling development that can be divided into two phases: (i) an LRP initiation phase dependent on a root tip-localized IAA source, and (ii) an LRP emergence phase dependent on leaf-derived IAA up to 10 days after germination. 相似文献
40.
Cotecchia S Björklöf K Rossier O Stanasila L Greasley P Fanelli F 《Journal of receptor and signal transduction research》2002,22(1-4):1-16
The aim of this review is to summarize some of the main findings from our laboratory as well as from others concerning the biochemical, molecular, and functional properties of the alpha1b-adrenergic receptor. Experimental and computational mutagenesis of the alpha1b-adrenergic receptor have been instrumental in elucidating some of the molecular mechanisms underlying receptor activation and receptor coupling to Gq. The knockout mouse model lacking the alpha1b-adrenergic receptor has highlighted the potential implication of this receptor subtype in variety of functions including the regulation of blood pressure, glucose homeostasis, and the rewarding response to drugs of abuse. 相似文献