bluuebunny/crossref_metadata_2025_split huggingface dataset:
Involvement of an influx transporter in the blood–brain barrier transport of naloxone
Authors: Suzuki Toyofumi , Ohmuro Aya , Miyata Mariko , Furuishi Takayuki , Hidaka Shinji , Kugawa Fumihiko , Fukami Toshiro , Tomono Kazuo 
Published: April 2010

AbstractNaloxone, a potent and specific opioid antagonist, has been shown in previous studies to have an influx clearance across the rat blood–brain barrier (BBB) two times greater than the efflux clearance. The purpose of the present study was to characterize the influx transport of naloxone across the rat BBB using the brain uptake index (BUI) method. The initial uptake rate of [3H]naloxone exhibited saturability in a concentration‐dependent manner (concentration range 0.5 µMto 15 mM) in the presence of unlabeled naloxone. These results indicate that both passive diffusion and a carrier‐mediated transport mechanism are operating. Thein vivokinetic parameters were estimated as follows: the Michaelis constant,Kt, was 2.99±0.71 mM; the maximum uptake rate,Jmax, was 0.477±0.083 µmol/min/g brain; and the nonsaturable first‐order rate constant,Kd, was 0.160±0.044 ml/min/g brain. The uptake of [3H]naloxone by the rat brain increased as the pH of the injected solution was increased from 5.5 to 8.5 and was strongly inhibited by cationic H1‐antagonists such as pyrilamine and diphenhydramine and cationic drugs such as lidocaine and propranolol. In contrast, the BBB transport of [3H]naloxone was not affected by any typical substrates for organic cation transport systems such as tetraethylammonium, ergothioneine orL‐carnitine or substrates for organic anion transport systems such asp‐aminohippuric acid, benzylpenicillin or pravastatin. The present results suggest that a pH‐dependent and saturable influx transport system that is a selective transporter for cationic H1‐antagonists is involved in the BBB transport of naloxone in the rat. Copyright © 2010 John Wiley & Sons, Ltd.
Effects of homogeneous and inhomogeneous static magnetic fields combined with gamma radiation on DNA and DNA repair
Authors: Kubinyi Györgyi , Zeitler Zsuzsanna , Thuróczy György , Juhász Péter , Bakos József , Sinay Hanna , László János 
Published: April 2010

AbstractThe aim of this study was to reveal whether static magnetic fields (SMFs) influence the repair of radiation‐damaged DNA on leukocytes or has any effect on DNA. After 4 Gy of 60Co‐γ irradiation, some of the samples were exposed to inhomogeneous SMFs with a lateral magnetic flux density gradient of 47.7, 1.2, or 0.3 T/m by 10 mm lateral periodicity, while other samples were exposed to homogeneous SMF of 159.2 ± 13.4 mT magnetic flux density for a time period of 0.5 min, 1, 2, 4, 6, 18, 20, or 24 h. Another set of samples was exposed to the aforementioned SMFs before gamma irradiation. The following three groups were examined: (i) exposed to SMF only, (ii) exposed to SMF following irradiation by 60Co‐γ, and (iii) exposed to SMF before 60Co‐γ irradiation. The analysis of the DNA damage was made by single‐cell gel electrophoresis technique (comet assay). Statistically significant differences were found at 1 h (iSMF), 4 h (hSMF), and 18 h (hSMF) if samples were exposed to only SMF, compared to control. When the SMF exposure followed the 60Co‐γ irradiation, statistically significant differences were found at 1 h (iSMF) and 4 h (hSMF). If exposure to SMF preceded 60Co‐γ irradiation, no statistically significant difference was found compared to 4 Gy gamma‐irradiated group. Bioelectromagnetics 31:488–494, 2010. © 2010 Wiley‐Liss, Inc.
A comparative study of solid and liquid non‐aqueous phases for the biodegradation of hexane in two‐phase partitioning bioreactors
Authors: Hernández María , Quijano Guillermo , Thalasso Frédéric , Daugulis Andrew J. , Villaverde Santiago , Muñoz Raúl 
Published: April 2010

AbstractA comparative study of the performance of solid and liquid non‐aqueous phases (NAPs) to enhance the mass transfer and biodegradation of hexane by Pseudomonas aeruginosa in two‐phase partitioning bioreactors (TPPBs) was undertaken. A preliminary NAP screening was thus carried out among the most common solid and liquid NAPs used in pollutant biodegradation. The polymer Kraton G1657 (solid) and the liquid silicone oils SO20 and SO200 were selected from this screening based on their biocompatibility, resistance to microbial attack, non‐volatility and high affinity for hexane (low partition coefficient: K = Cg/CNAP, where Cg and CNAP represent the pollutant concentration in the gas phase and NAP, respectively). Despite the three NAPs exhibited a similar affinity for hexane (K ≈ 0.0058), SO200 and SO20 showed a superior performance to Kraton G1657 in terms of hexane mass transfer and biodegradation enhancement. The enhanced performance of SO200 and SO20 could be explained by both the low interfacial area of this solid polymer (as a result of the large size of commercial beads) and by the interference of water on hexane transfer (observed in this work). When Kraton G1657 (20%) was tested in a TPPB inoculated with P. aeruginosa, steady state elimination capacities (ECs) of 5.6 ± 0.6 g m−3 h−1 were achieved. These values were similar to those obtained in the absence of a NAP but lower compared to the ECs recorded in the presence of 20% of SO200 (10.6 ± 0.9 g m−3 h−1). Finally, this study showed that the enhancement in the transfer of hexane supported by SO200 was attenuated by limitations in microbial activity, as shown by the fact that the ECs in biotic systems were far lower than the maximum hexane transfer capacity recorded under abiotic conditions. Biotechnol. Bioeng. 2010;106: 731–740. © 2010 Wiley Periodicals, Inc.
Enhancement of DNA uptake in FUT8‐deleted CHO cells for transient production of afucosylated antibodies
Authors: Wong Athena W. , Baginski Tomasz K. , Reilly Dorothea E. 
Published: April 2010

AbstractRemoval of the core α1,6 fucose from the glycans in the Fc region of IgG1 antibodies has been demonstrated to improve antibody‐dependent cellular cytotoxicity (ADCC) activity. In order to produce afucosylated antibodies using transient transfection, a FUT8 knockout (FUT8KO) cell line was generated in a CHO host cell line using the zinc finger nuclease technology. Transient transfection of DNA into mammalian cells using the cationic polymer, polyethylenimine (PEI), is commonly used for rapid generation of recombinant proteins. FUT8KO cells evaluated in PEI transfections yielded lower titers than parental CHO WT cells. FACS and HPLC analyses revealed that the FUT8KO cells had lower cell surface heparan sulfate (HS) levels than CHO WT. Removal of cell surface HS resulted in reduced uptake of PEI‐transfected DNA (PEI:DNA) and lower transfection titers suggesting that PEI:DNA relies on HS for binding and cellular entry. The absence of cell surface HS did not severely impact transfections performed with cationic liposomes. We undertook two approaches to improve transient production of afucosylated antibodies. First, we evaluated transfection of FUT8KO cells with cationic liposomes, which were observed to be less dependent on HS levels for uptake. Transfection of FUT8KO cells using the cationic liposome, DMRIE‐C, produced similar titers to CHO WT in both shake flask and large‐scale 10 L bioreactors. The second approach was to engineer a cell line overexpressing exostosin‐1 (EXT1), an enzyme responsible for HS chain elongation, to increase HS content. EXT1‐FUT8KO and CHO WT cells produced comparable levels of antibody from PEI transfections. Biotechnol. Bioeng. 2010;106: 751–763. © 2010 Wiley Periodicals, Inc.
Production of a non‐triple helical collagen α chain in transgenic silkworms and its evaluation as a gelatin substitute for cell culture
Authors: Adachi Takahiro , Wang Xiaobiao , Murata Tomoko , Obara Masanobu , Akutsu Hidenori , Machida Masakazu , Umezawa Akirihiro , Tomita Masahiro 
Published: April 2010

AbstractWe generated transgenic silkworms that synthesized human type I collagen α1 chain [α1(I) chain] in the middle silk glands and secreted it into cocoons. The initial content of the recombinant α1(I) chain in the cocoons of the transgenic silkworms was 0.8%. The IE1 gene, a trans‐activator from the baculovirus, was introduced into the transgenic silkworm to increase the content of the chain. We also generated silkworms homozygous for the transgenes. These manipulations increased the α1(I) chain content to 8.0% (4.24 mg per cocoon). The α1(I) chain was extracted and purified from the cocoons using a very simple method. The α1(I) chain contained no hydroxyprolines due to the absence of prolyl‐hydroxylase activity in the silk glands. Circular dichroism analysis showed that the secondary structure of the α1(I) chain is similar to that of denatured type I collagen, demonstrating the absence of the triple helical structure. Human skin fibroblasts were seeded on the α1(I) chain‐coated dishes. The cells attached and spread, although at decreased chain concentrations the spreading rate was lower than that of the collagen and gelatin. Cynomolgus monkey embryonic stem cells cultured on the α1(I) chain‐coated dishes maintained an undifferentiated state after 30 passages, and their pluripotency was confirmed by teratoma formation in severe combined immunodeficient mice. These results show that the recombinant human α1(I) chain is a promising candidate biomaterial as a high‐quality and safe gelatin substitute for cell culture. Biotechnol. Bioeng. 2010;106: 860–870. © 2010 Wiley Periodicals, Inc.
The replacement of the Neumann trend test and the Durbin–Watson test on residuals by one‐way ANOVA with resampling and an extension of the tests to different time lags
Authors: Tóth Gergely 
Published: April 2010

AbstractIn our investigation we focused on the replacement and on the extension of two traditional parametric tests used for detecting trend and autocorrelation in time series. We found that the Neumann test of gradual trend and the Durbin–Watson test of residuals can be replaced by one‐way analysis of variance (ANOVA) with resampling. Resampling meant a proper choice of numerous pairs of data, where each pair consisted of two successive data points.We extended the Neumann test, the Durbin–Watson test and our ANOVA method with the introduction of time lag. If the resampled data consisted of pairs with a time lag of h, we obtained a set of tests with different answers on the hypothesis at the h‐values. The time lag extended tests with resampling seemed to be efficient in the detection of hidden autocorrelation, trend and relevant time scales for data modelling.The methods were compared on simple model data and on data of air pollutants recorded in Hungary. The Neumann(h) and the ANOVA(h) curves were specific for the different pollutant and helped to detect and explain local peculiarities. Copyright © 2010 John Wiley & Sons, Ltd.
Random projection experiments with chemometric data
Authors: Varmuza Kurt , Filzmoser Peter , Liebmann Bettina 
Published: April 2010

AbstractRandom projection (RP) is a linear method for the projection of high‐dimensional data onto a lower dimensional space. RP uses projection vectors (loading vectors) that consist of random numbers taken from a symmetric distribution with zero mean; many successful applications have been reported for high‐dimensional data sets. The basic ideas of RP are presented, and tested with artificial data, data from chemoinformatics and from chemometrics. RP's potential in dimensionality reduction is investigated by a subsequent cluster analysis, classification or calibration, and is compared to PCA as a reference method. RP allowed drastic reduction in data size and computing time, while preserving the performance quality. Successful applications are shown in structure similarity searches (53 478 chemical structures characterized by 1233 binary substructure descriptors) and in classification of mutagenicity (6506 chemical structures characterized by 1455 molecular descriptors). Only in calibration tasks with low‐dimensional data as in many chemical applications, RP showed limited performance. For special applications in chemometrics with very large data sets and/or severe restrictions for hardware and software resources, RP is a promising method. Copyright © 2010 John Wiley & Sons, Ltd.
Applicability domain for in silico models to achieve accuracy of experimental measurements
Authors: Sushko Iurii , Novotarskyi Sergii , Körner Robert , Pandey Anil Kumar , Kovalishyn Vasily V. , Prokopenko Volodymyr V. , Tetko Igor V. 
Published: April 2010

AbstractThe accuracy of in silico models can be inhomogeneous: models can show excellent performance on some chemical subspaces but have low accuracy on others. We show that applicability domain (AD) approaches can differentiate reliable and non‐reliable predictions and identify those with experimental accuracy for both regression and classification models. For reliably predicted molecules, the predicted values can be used instead of experimental measurements. This can halve time and costs of experimental measurements. The developed classification models for AMES mutagenicity test and CYP450 inhibition, which are important drug discovery properties, are publicly available at the online chemical database and modeling environment (OCHEM) site http://qspr.eu Copyright © 2010 John Wiley & Sons, Ltd.
Application of recurrent relations in chemistry
Authors: Zenkevich Igor G. 
Published: April 2010

AbstractAs it was previously demonstrated, mathematical properties of simplest first‐order recurrent relations A(n + 1) = aA(n) + b provide important advantages at their applications in chemistry, namely in the approximation of monotonous variations of different physicochemical properties of homologues of various series of organic compounds. Besides that it was empirically revealed the unique ‘chemical’ property of recurrences that is the application of single equations of this kind to constants of different series. To explain this high ‘approximating ability’ of recurrences it was proved first time that numerical sequences that obey high‐order recurrence in a limiting case can be approximated by first‐order recurrence. Consequently, this fact explains us the existence of close analogy between first‐order recurrent approximation of recursive numerical sequences (Fibonacci, Padovan, Lucas and Perrin sequences are considered as examples) and physicochemical constants of homologues. This analogy is considered as not ‘chemically’ correct proof, but reasonable explanation of the applicability of single recurrent equations to constants of different homologous series. The mentioned properties of recurrences seem to be the reason of their high approximating ability in relation to different chemical variables. Recurrent relations can be recommended as universal approach in processing of not only various sets of physicochemical constants of homologues, but also properties or processes characterized by equidistant values of arguments. Copyright © 2010 John Wiley & Sons, Ltd.
Impact of standardization sample design on Tikhonov regularization variants for spectroscopic calibration maintenance and transfer
Authors: Kunz Matthew R. , Ottaway Joshua , Kalivas John H. , Andries Erik 
Published: April 2010

AbstractMultivariate spectroscopic calibration models are only valid to predict samples within the span of the calibration sample space measured relative to the current instrument environment (the primary conditions). Predicting samples in secondary conditions with new variances, same sample variances as the calibration space but a new instrument environment, or both, requires some form of continual model maintenance and/or transfer. Previous work has shown that a Tikhonov regularization (TR) approach is capable of accomplishing both tasks by updating the primary model based on only a few samples (transfer or standardization set) measured under the secondary conditions. A distinction of the TR design for calibration maintenance and transfer is a defined weighting scheme for the small set of standardization samples augmented to the full set of primary calibration samples. Critical to successful calibration maintenance or transfer is the standardization sample set composition, i.e. standardization samples should properly represent that are less secondary conditions. This paper reports on using TR‐based methods to investigate this issue and a consensus modeling approach is briefly evaluated. Copyright © 2010 John Wiley & Sons, Ltd.
Development of semi‐empirical electrotopological index using the atomic charge in QSPR/QSRR models for alcohols
Authors: Souza Érica Silva , Kuhnen Carlos Alberto , da Silva Junkes Berenice , Yunes Rosendo Augusto , Heinzen Vilma Edite Fonseca 
Published: April 2010

AbstractThe semi‐empirical electrotopological index (ISET) used for quantitative structure‐retention relationship (QSRR) models firstly developed for alkanes and alkenes, was remodeled for different organic compounds such as ketones, aldehydes and esters. In this study, the ISET was developed and optimized to describe the chromatographic retention of aliphatic alcohols on six different stationary phases (SE‐30, OV‐3, OV‐7, OV‐11, OV‐17 and OV‐25). The presence of a hydroxyl group leads to a charge redistribution increasing the interactions between these molecules and the stationary phases relative to the interactions between hydrocarbons and the same stationary phases. These considerations were included in the calculation of ISET. The simple linear regressions (SLR) between retention indices and the ISET for each stationary phase showed good statistical quality, high internal stability and good predictive ability for external groups, especially for stationary phases with low polarity. A single combined model, in which the McReynolds polarity term was added as a descriptor, was developed for all the data points for the stationary phases and the results were of satisfactory predictive quality. The efficiency and the applicability of the approach were demonstrated through the high quality quantitative structure‐property relationship (QSPR) model for the boiling point (BP). For this physical property 134 compounds were used; most of them were not included in the original data set employed to develop the ISET. Copyright © 2010 John Wiley & Sons, Ltd.
Deterministic fallacies and model validation
Authors: Hawkins Douglas M. , Kraker Jessica 
Published: April 2010

AbstractStochastic settings differ from deterministic ones in many subtle ways, making it easy to slip into errors through applying deterministic thinking inappropriately. We suspect this is the cause of much of the disagreement about model validation. A further technical issue is a common misapplication of cross‐validation, in which it is applied only partially, leading to incorrect results. Statistical theory and empirical investigation verify the efficacy of cross‐validation when it is applied correctly. In settings where data are relatively scarce, cross‐validation is attractive in that it makes the maximum possible use of all available information, at the cost of potentially substantial computation. The bootstrap is another method that makes full use of all available data for both model fitting and model validation, at a cost of substantially increased computation, and it shares many of the broad philosophical background of cross‐validation. Increasingly, the computational cost of these methods is not a major concern, leading to the recommendation, in most circumstances, to use cross‐validation or bootstrapping rather than the earlier standard method of splitting the available data into a learning and a testing portion. Copyright © 2010 John Wiley & Sons, Ltd.
The role of the C(2) configuration and methyl substitution on the catalytic activity of novel 2,3,3‐ and 2,7,7‐trimethyl‐substituted γ‐aminonorbornan‐2‐ols
Authors: Martínez Antonio García , Vilar Enrique Teso , Fraile Amelia García , Cerero Santiago de la Moya , Ruiz Paloma Martínez , Morillo Cristina Díaz 
Published: April 2010

AbstractA new set of optically active 2,3,3‐ and 2,7,7‐trimethyl‐substituted γ‐aminonorbornan‐2‐ols have been obtained from 2‐methylenenorbornane‐1‐carbonitriles derived from (+)‐camphor and (−)‐fenchone and probed as chiral ligands for the enantioselective addition of diethylzinc to benzaldehyde. This has allowed the study of the structural factors influencing the chirality transfer, such as variation of the relative configuration at C(2) and steric hindrance at C(2), C(3), and C(7) positions of norbornane, which result in the observance of the important role played by the gem‐dimethyl position in γ‐aminonorbornan‐2‐exo‐ols. An empirical rationalization of the obtained experimental results has been realized on the basis of energetically‐favored diastereomeric Noyori‐like transition states. Chirality 2010. © 2010 Wiley‐Liss, Inc.
Factors affecting supramolecular exciton intensity
Authors: Simonyi Miklós 
Published: April 2010

AbstractThe effect of nonchromophoric additives on supramolecular exciton intensity was tested. Fatty acids and 1‐dodecanol decreased exciton intensity of the tightly packed aggregate of 6′R‐capsanthol‐3′‐on, whereas all esters studied increased exciton intensity. These results apparently confirm the validity of the treatment of Harada for supramolecular systems too. Chirality 2010. © 2010 Wiley‐Liss, Inc.
Mixing intensification for the mineral industry
Authors: Wu Jie , Graham Lachlan , Nguyen Bon 
Published: April 2010

AbstractThe modern mineral industry uses hydrometallurgical processes to extract metals from ores. Typically, a large volume of ore slurry is treated in mixing tanks in a mineral processing plant, for leaching, digestion, precipitation, and other chemical processing to obtain pure metals or concentrated ores. This paper discusses mixing intensification as a means to achieve process intensification for the mineral process industry. Areas where mixing intensification can be applied are illustrated with case examples. Among them, it was suggested that for slowly reacting slurry systems typical in the mineral processing operations, high solid loadings should be considered to boost throughput. Improved agitator energy efficiency can be achieved by removing baffles, at very high solid loadings. Slurry stratification in tanks can be used to boost either solids residence time or slurry through flow.
Theoretical pressure dependency of carbon dioxide solubility under hydrate–liquid water equilibrium
Authors: Bergeron Sebastien , Beltrán Juan G. , Macchi Arturo , Servio Phillip 
Published: April 2010

AbstractThe effect of pressure on carbon dioxide solubility in water is significantly smaller than that of temperature under hydrate–liquid water (H–Lw) equilibrium. As a result, experimental values of carbon dioxide solubility in the water rich liquid phase under H–Lw equilibrium are often inconclusive and in some cases contradictory. This work proposes a theoretical derivation, based on fundamental thermodynamics, of the gas hydrate former solubility dependency on pressure for any binary system under two‐phase equilibrium. The obtained expression is applied to the carbon dioxide–water system under both hydrate–liquid water and vapour–liquid water equilibrium. It is shown that the solubility of carbon dioxide in the water rich liquid phase increases with increasing pressure under H–Lw equilibrium. The predicted trend is then compared to the limited experimental data available in the literature.