Kinetic preference for interaction of cisplatin with the G-C-rich wobble basepair region in both tRNAAla and MhAla

The anticancer active complex cisplatin interacts preferentially with the common, G-C rich, wobble base pair region of both tRNA(Ala) and Mh(Ala) in a reaction that at pH 6.3 is rate limited by the acid hydrolysis of the metal complex.     

Reduction of nonspecific protein binding on surface plasmon resonance biosensors

Reduction of the nonspecific serum protein adsorption on a gold surface to levels low enough to allow the detection of biomarkers in complex media has been achieved using the N-hydroxysuccinimide (NHS) ester of 16-mercaptohexadecanoic acid. Carboxymethylated dextran (CM dextran), which is widely used, nonspecifically adsorbs enough proteins to mask the signal from target biomarkers in complex solutions such as serum or blood. The use of short-chain thiols greatly reduces the amount of nonspecific protein adsorption. Mixed layers of 11-mercaptoundecanoic acid or the NHS ester of 11-mercaptoundecanoic acid mixed layers with either 11-mercaptoundecanol or undecanethiol, and 16-mercaptohexadecanoic acid or the NHS ester of 16-mercaptohexadecanoic acid with hexadecanethiol, were also investigated for nonspecific protein binding properties as well as for biomarker signal response. The NHS ester of 16-mercaptohexadecanoic acid exhibits the largest signal for the biomarker myoglobin (including CM dextran) while offering a significantly diminished amount of nonspecific binding. The sensor has also been shown to detect interleukin-6 in cell culture media containing protein concentrations of at least 4 mg/mL.     

The selective and efficient laser ion source and trap project LIST for on-line production of exotic nuclides

Laser ion sources based on resonant excitation and ionization of atoms are well-established tools for selective and efficient production of radioactive ion beams. A recent trend is the complementary installation of reliable state-of-the-art all solid-state Ti:Sapphire laser systems. To date, 35 elements of the Periodic Table are available at laser ion sources by using these novel laser systems, which complements the overall accessibility to 54 elements including use of traditional dye lasers. Recent progress in the field concerns the identification of suitable optical excitation schemes for Ti:Sapphire laser excitation as well as technical developments of the source in respect to geometry, cavity material as well as by incorporation of an ion guide system in the form of the laser ion source trap LIST.     

Vowel spaces in Swedish adolescents with cochlear implants

This paper examines vowel production in Swedish adolescents with cochlear implants. Twelve adolescents with cochlear implants and 11 adolescents with normal hearing participated. Measurements were made of the first and second formants in all the nine long Swedish vowels. The values in hertz were bark-transformed, and two measures of the size of the vowel space were obtained. The first of them was the average Euclidean distance in the F1-F2 plane between the nine vowels and the mean F1 and F2 values of all the vowels. The second was the mean Euclidean distance in the F1-F2 plane between all the vowels. The results showed a significant difference for both vowel space measures between the two groups of adolescents. The cochlear implant users had a smaller space than the adolescents with normal hearing. In general, the size of the vowel space showed no correlations with measures of receptive and productive linguistic abilities. However, the results of an identification test showed that the listeners made more confusions of the vowels produced by speakers who had a small mean distance in the F1-F2 plane between all the vowels.     

Electro‐driven extraction of inorganic anions from water samples and water miscible organic solvents and analysis by ion chromatography

A simple electromembrane extraction (EME) procedure combined with ion chromatography (IC) was developed to quantify inorganic anions in different pure water samples and water miscible organic solvents. The parameters affecting extraction performance, such as supported liquid membrane (SLM) solvent, extraction time, pH of donor and acceptor solutions, and extraction voltage were optimized. The optimized EME conditions were as follows: 1‐heptanol was used as the SLM solvent, the extraction time was 10 min, pHs of the acceptor and donor solutions were 10 and 7, respectively, and the extraction voltage was 15 V. The mobile phase used for IC was a combination of 1.8 mM sodium carbonate and 1.7 mM sodium bicarbonate. Under these optimized conditions, all anions had enrichment factors ranging from 67 to 117 with RSDs between 7.3 and 13.5% (n = 5). Good linearity values ranging from 2 to 1200 ng/mL with coefficients of determination (R²) between 0.987 and 0.999 were obtained. The LODs of the EME‐IC method ranged from 0.6 to 7.5 ng/mL. The developed method was applied to different samples to evaluate the feasibility of the method for real applications.     

Rheology of nanofibrillated cellulose/acrylate systems for coating applications

In this work, the suitability of nanofibrillated cellulose (NFC) as a novel component for wood coatings has been evaluated. NFC was prepared from two different wood pulps with a high pressure homogeniser and a grinder, depending on the initial fibre size of the two pulps. The fibrillation process was monitored using viscosity measurements and scanning electron microscopy. Viscosity measurements were found to be a suitable, reliable and especially fast and easy method for process monitoring, optimization and quality assessment of the NFC fibrillation process. NFC was mixed with four different waterborne acrylic polymer emulsions and analysed regarding its rheological behaviour. The viscosity of the acrylate–NFC suspensions was dominated by the NFC, whereas the polymer type was of minor importance at the tested concentrations. The viscosity increased exponentially after NFC addition and consequently the viscosity of such suspensions would be precisely adjustable in the considered shear range. During accelerated storage at elevated temperatures, the general flow behaviour did not change; only a slight viscosity increase was observed. The study shows that rheology is an important issue that has to be taken into account when applying NFC as additive in water based coating systems and that NFC is suitable as component for coating applications.     

Molecular and Functional Analysis of Human β-Defensin 3 Action at Melanocortin Receptors

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Effects of Lipid-Based Encapsulation on the Bioaccessibility and Bioavailability of Phenolic Compounds

Phenolic compounds (quercetin, rutin, cyanidin, tangeretin, hesperetin, curcumin, resveratrol, etc.) are known to have health-promoting effects and they are accepted as one of the main proposed nutraceutical group. However, their application is limited owing to the problems related with their stability and water solubility as well as their low bioaccessibility and bioavailability. These limitations can be overcome by encapsulating phenolic compounds by physical, physicochemical and chemical encapsulation techniques. This review focuses on the effects of encapsulation, especially lipid-based techniques (emulsion/nanoemulsion, solid lipid nanoparticles, liposomes/nanoliposomes, etc.), on the digestibility characteristics of phenolic compounds in terms of bioaccessibility and bioavailability.     

Numerically stable algorithm for cycloidal splines

We propose a knot insertion algorithm for splines that are piecewisely in L{1, x, sin x, cos x}. Since an ECC-system on [0, 2π] in this case does not exist, we construct a CCC-system by choosing the appropriate measures in the canonical representation. In this way, a B-basis can be constructed in much the same way as for weighted and tension splines. Thus we develop a corner cutting algorithm for lower order cycloidal curves , though a straightforward generalization to higher order curves, where ECC-systems exist, is more complex. The important feature of the algorithm is high numerical stability and simple implementation. This research was supported by Grant 037-1193086-2771, by the Ministry of science, higher education and sports of the Republic of Croatia.     

Investigation of expected location of muonium in normal state in III–V semiconductors and associated muon hyperfine interaction

The location and hyperfine properties of muonium in AlP is investigated by the unrestricted Hartree-Fock cluster procedure. Two minima are found, one at the aluminium tetrahedral interstitial site, and the other at the corresponding phosphorus site. The former is deeper by 0.25 eV and separated from the other minimum by a steep maximum of 0.63 eV in the hexagonal region. Using the calculated electronic wave functions, the muon hyperfine constant, after vibrational averaging, comes out smaller than the value for free muonium, the ratio being 0.93. This value is, however, significantly higher than the experimental results in GaP and GaAs.Briefly reported in Abstract at American Physical Society meeting in New Orleans, March 1988, see Bull. Am. Phys. Soc. 33 (1988) 1364.