bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mutated polyadenylation signals for controlling expression levels of multiple genes in mammalian cells
Authors: Yang Yuansheng , Mariati  , Ho Steven C.L. , Yap Miranda G.S. 
Published: September 2008

AbstractA set of mutated SV40 early polyadenylation signals (SV40pA) with varying strengths is generated by mutating the AATAAA sequence in the wild‐type SV40pA. They are shown to control the expression level of a gene over a 10‐fold range using luciferase reporter genes in transient transfection assays. The relative strength of these SV40pA variants remains similar under three commonly used mammalian promoters and in five mammalian cell lines. Application of SV40pA variants for controlling expression level of multiple genes is demonstrated in a study of monoclonal antibody (mAb) synthesis in mammalian cells. By using SV40pA variants of different strengths, the expression of light chain (LC) and heavy chain (HC) genes encoded in a single vector is independently altered which results in different ratios of LC to HC expression spanning a range from 0.24 to 16.42. The changes in gene expression are determined by measuring mRNA levels and intracellular LC and HC polypeptides. It is found that a substantial decrease of HC expression, which increases the LC/HC mRNA ratio, only slightly reduces mAb production. However, reducing the LC expression by a similar magnitude, which decreases the LC/HC mRNA ratio results in a sharp decline of mAb production to trace amounts. This set of SV40pA variants offers a new tool for accurate control of the relative expression levels of multiple genes. It will have wide‐ranging applications in fields related to the study of biosynthesis of multi‐subunit proteins, proteomic research on protein interactions, and multi‐gene metabolic engineering. Biotechnol. Bioeng. 2009;102: 1152–1160. © 2008 Wiley Periodicals, Inc.
HPLC‐UV assay for monitoring total and unbound mycophenolic acid concentrations in children
Authors: Zeng L. , Nath C. E. , Shaw P. J. , Earl J. W. , McLachlan A. J. 
Published: September 2008

AbstractA simple, accurate and sensitive HPLC method was developed for measuring total and unbound mycophenolic acid (MPA) in human plasma. Total MPA was extracted by protein precipitation and ultrafiltration was used to assess unbound MPA concentrations. The supernatant (20 µL) or ultrafiltrate (100 µL) was injected onto a C18 HPLC column with a mobile phase of 0.05 m sodium phosphate buffer (pH 2.31)–acetonitrile (55:45, v/v for total MPA; 50:50 for unbound MPA) with UV detection at 254 nm. The extraction recovery was over 93% and reproducible. The assay was linear over the concentration range of 0.07–50 mg/L for total MPA and 4–1500 µg/L for unbound MPA. Intra‐ and inter‐day assay reproducibility was less than 10%. Detection limits were 0.04 mg/L and 2 µg/L for total and unbound MPA, respectively. The assay utility was established in samples collected from five paediatric bone marrow transplant recipients who were receiving intravenous doses of mycophenolate mofetil. In these patients MPA concentrations ranged from 0.07 to 7.83 mg/L and unbound drug concentrations ranged from 2.1 to 107.5 µg/L. This method can be effectively applied to MPA pharmacokinetics in paediatric patients. Copyright © 2008 John Wiley & Sons, Ltd.
Characteristics of Oxidation of Diesel Paticulate Matter over a Spinel Type Cu0.95K0.05Fe2O4 Catalyst
Authors: Lin H. , Huang Z. , Shangguan W. 
Published: September 2008

AbstractThis paper presents an experimental study on oxidation of diesel paticulate matter (PM) and aims at investigating the characteristics of PM oxidation. The experiments were performed over a Cu0.95K0.05Fe2O4 catalyst which is attributed to a spinel type metal oxide. The effects of O2 on PM oxidation as well as on NOx reduction were studied and the roles of O2 in PM oxidation and in NOx reduction, respectively, are discussed. During the temperature‐programmed oxidation of PM, SOF oxidation and soot oxidation lead to two CO2 peaks at different temperatures. It was found that the presence of O2 benefits PM oxidation but suppresses the reduction of NOx into N2 by consuming the soot. This study revealed that the appearance of PM oxidation is different from that of soot oxidation. The mechanisms on PM oxidation and NOx reduction are discussed.
Effect of Structured Packing Characteristics on Styrene Monomer/Ethylbenzene Distillation Process
Authors: Salem A. , Shokrkar H. 
Published: September 2008

AbstractThe application of various types of structured packings to separate styrene monomer/ethyl benzene in packed columns is presented. The investigation was conducted over a wide range of operating conditions such as packing type, pressure, and reflux ratio. Several structured packings were used for separation of styrene monomer/ethyl benzene and the optimum conditions were determined for each of them. The proper condition of separation process and appropriate parameters for achieving better efficiency was discussed. The calculated results were compared with those obtained in industrial scale. It was shown that Mellapak‐Plus 252Y and 452Y packings can provide the maximum capacity with an acceptable level of efficiency over a wide range of operating conditions.
Heterogeneous Catalysis in Supercritical Media, Part 3: Other Media
Authors: Kruse A. , Vogel H. 
Published: September 2008

AbstractFor technical applications, those reactions in supercritical fluids are of particular interest which have significant advantages over conventional methods or which are impossible in classical solvents or in the gas phase. This last part of the trilogy deals with heterogeneously catalyzed reactions in supercritical fluids other than carbon dioxide or water.
Complex Hydrothermal Reaction Systems: A Systematic Investigation of Copper Phosphonatoethanesulfonates by High‐Throughput Methods
Authors: Sonnauer Andreas , Stock Norbert 
Published: September 2008

AbstractThe polyfunctional ligand 2‐phosphonoethanesulfonic acid, H2O3P–C2H4–SO3H (H3L), was used in a high‐throughput (HT) investigation of a new class of compounds, the copper phosphonatosulfonates. An extensive HT study comprising 288 individual hydrothermal reactions was performed to systematically investigate the influence of temperature, pH, and molar ratio of Cu2+/H3L in the reaction system Cu(NO3)2/H3L/NaOH/H2O/temperature. The HT investigation led to five new compounds Cu2[(O3P–C2H4–SO3)(OH)(H2O)](H2O) (1), Cu2.5(O3P–C2H4–SO3)(OH)2 (2), Cu1.5[(O3P–C2H4–SO3)(H2O)]·H2O (3), Cu2[(O3P–C2H4–SO3)(OH)(H2O)2]·3H2O (4), and NaCu(O3P–C2H4–SO3)(H2O)3 (5). Their fields of formation were established unequivocally and from the large amount of data reaction trends were extracted. Furthermore, a new compound Cu1.5(O3P–C2H4–SO3)(H2O) (6) was synthesized under hydrothermal reaction conditions in a glass reactor. For compounds 1, 2, and 6 crystal structures were determined by single‐crystal X‐ray diffraction. The compounds exhibit a large structural variety. Thus, CuO4, CuO5, and CuO6 units are observed. Corner‐, edge‐ as well as face‐sharing polyhedra form chains, layers, or Cu3O12 clusters that are connected by the –CH2CH2– group of the ligand. Thermogravimetric investigations, magnetic measurements, IR spectra as well as chemical analyses of compounds 1, 3, 4, 5, and 6 are also presented.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Enzymatic Method for the Synthesis of Blockbuster Drug Intermediates – Synthesis of Five‐Membered Cyclic γ‐Amino Acid and γ‐Lactam Enantiomers
Authors: Forró Enikő , Fülöp Ferenc 
Published: September 2008

AbstractA very efficient enzymatic method was developed for the synthesis of cyclic γ‐lactam and γ‐amino acid enantiomers, intermediates for drugs with a prominent turnover (e.g., abacavir and carbovir), through the CAL‐B‐catalysed enantioselective (E > 200) hydrolysis of the corresponding N‐Boc protected and unprotected racemic γ‐lactams with H2O in iPr2O. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Direct Electrochemistry and Electrocatalysis of Hemoglobin/ZnO‐Chitosan/nano‐Au Modified Glassy Carbon Electrode
Authors: Duan Guoping , Li Yinfeng , Wen Yin , Ma Xiaoling , Wang Yao , Ji Jiahua , Wu Ping , Zhang Zongrang , Yang Haifeng 
Published: September 2008

AbstractThe highly efficient H2O2 biosensor was fabricated on the basis of the complex films of hemoglobin (Hb), nano ZnO, chitosan (CHIT) dispersed solution and nano Au immobilized on glassy carbon electrode (GCE). Biocompatible ZnO‐CHIT composition provided a suitable microenvironment to keep Hb bioactivity (Michaelis‐Menten constant of 0.075 mmol L−1). The presence of nano Au in matrix could effectively enhance electron transfer between Hb and electrode. The electrochemical behaviors and effects of solution pH values were carefully examined in this paper. The (ZnO‐CHIT)‐Au‐Hb/GCE demonstrated excellently electrocatalytical ability for H2O2. This biosensor had a fast response to H2O2 less than 4 s and excellent linear relationships were obtained in the concentration range from1.94×10−7 to 1.73×10−3 mol L−1 with the detection limit of 9.7×10−8 mol L−1 (S/N=3) under the optimum conditions. Moreover, the stability and reproducibility of this biosensor were evaluated with satisfactory results.
Hepatic steatosis in response to acute alcohol exposure in zebrafish requires sterol regulatory element binding protein activation #
Authors: Passeri Michael J. , Cinaroglu Ayca , Gao Chuan , Sadler Kirsten C. 
Published: September 2008

Abstract
Steatosis is the most common consequence of acute alcohol abuse and may predispose to more severe hepatic disease. Increased lipogenesis driven by the sterol response element binding protein (SREBP) transcription factors is essential for steatosis associated with chronic alcohol ingestion, but the mechanisms underlying steatosis following acute alcohol exposure are unknown. Zebrafish larvae represent an attractive vertebrate model for studying alcoholic liver disease (ALD), because they possess the pathways to metabolize alcohol, the liver is mature by 4 days post-fertilization (dpf), and alcohol can be simply added to their water. Exposing 4 dpf zebrafish larvae to 2% ethanol (EtOH) for 32 hours achieves ˜80 mM intracellular EtOH and up-regulation of hepatic cyp2e1, sod, and bip, indicating that EtOH is metabolized and provokes oxidant stress. EtOH-treated larvae develop hepatomegaly and steatosis accompanied by changes in the expression of genes required for hepatic lipid metabolism. Based on the importance of SREBPs in chronic ALD, we explored the role of Srebps in this model of acute ALD. Srebp activation was prevented in gonzo larvae, which harbor a mutation in the membrane-bound transcription factor protease 1 (mbtps1) gene, and in embryos injected with a morpholino to knock down Srebp cleavage activating protein (scap). Both gonzo mutants and scap morphants were resistant to steatosis in response to 2% EtOH, and the expression of many Srebp target genes are down-regulated in gonzo mutant livers. Conclusion: Zebrafish larvae develop signs of acute ALD, including steatosis. Srebp activation is required for steatosis in this model. The tractability of zebrafish genetics provides a valuable tool for dissecting the molecular pathogenesis of acute ALD. (Hepatology 2008.)
A method to estimate mortality trends when death certificates are imprecisely coded: An application to cervical cancer in Italy
Authors: Capocaccia Riccardo , Martina Lucia , Inghelmann Riccardo , Crocetti Emanuele , De Lisi Vincenzo , Falcini Fabio , Guzzinati Stefano , Rosso Stefano , Tagliabue Giovanna , Tumino Rosario , Vercelli Marina , Zanetti Roberto , De Angelis Roberta 
Published: September 2008

AbstractSystematic analysis of mortality trends of cervix and corpus uteri cancers is difficult in Italy, as in many other countries, because of the poor specification of uterine cancer subsites in official death statistics. The aim of this article is to propose a method for the analysis of uterine cancers mortality based on high quality incidence and prevalence data from population‐based cancer registries. The method assumes that the excess mortality of cancer patients, compared to death rates expected in the general population, is attributable to the specific cancer. The method is applied to estimate mortality trends for cancers of cervix, corpus and uterus as whole, during the period 1987–1999, in an area covered by 8 Italian cancer registries. Official mortality rates for the 2 subsites were about 60% lower than excess mortality rates, due to the very high proportion of deaths attributed to not specified subsite. Age adjusted cervical cancer excess mortality rates decreased from 3.7 to 2.7 × 100,000 women. Excess mortality for corpus uteri cancer remained approximately stable between 3 and 3.3 × 100,000 women in the period 1990–1999. The results support the efficacy of organized screening in reducing cervical cancer mortality. The same method can be used to assess mortality rates for every cancer entity identifiable in cancer registries data, not otherwise available from official death records. © 2008 Wiley‐Liss, Inc.
Estimation of soil water content and evapotranspiration from irrigated cropland on the North China Plain
Authors: Jiang Jie , Zhang Yongqiang , Wegehenkel Martin , Yu Qiang , Xia Jun 
Published: September 2008

AbstractFor nearly 30 y, cropland on the North China Plain (NCP) has been irrigated primarily by pumping groundwater with no sustainable management strategy. This has caused a continuous decline of the water table. A sustainable groundwater management and irrigation strategy must be established in order to prevent further decline of the water table; to do this, one must quantify soil water content and daily rates of deep percolation and locate evapotranspiration from irrigated cropland. For that purpose, we developed a three‐layer soil–water balance (SWB) model based on an approach described by Kendy et al. (2003). In this model, the unsaturated soil zone is divided into three layers: a surface active layer, a middle active soil layer, and a lowest passive soil layer. The middle and the lowest layers dynamically change with the development of crop rooting depth. A simple “tipping bucket” routine and an exponential equation are used to redistribute soil water in the three soil layers. The actual evapotranspiration estimated is partitioned into soil evaporation and crop transpiration using a dual crop coefficient reference approach. At first, the model was calibrated using data obtained from five deficiently irrigated field plots located at an experimental site in the NCP between 1998 and 2003. Then, the model was validated by comparing estimated soil water contents with measured ones at three other plots with nondeficient irrigation. The estimates of actual evapotranspiration were compared with those measured with a large‐scale weighing lysimeter (3 m2). The index of agreement (IA) for soil water contents varied between 0.62 and 0.80; the concordance correlation coefficient (CCC) and the root mean square error obtained from the same comparison were 0.34–0.65 and 0.043–0.074 cm3 cm–3, respectively. The rates of 10 d mean evapotranspiration estimated by the model show a good fit to those measured by the large‐scale lysimeter; this is indicated by IA = 0.94 and CCC = 0.88. Our results indicate that at the irrigated cropland on the plain, deep soil water–percolation rates are usually <200 mm y–1 under nondeficient‐irrigation conditions.
Fluxes of climate‐relevant trace gases between a Norway spruce forest soil and atmosphere during repeated freeze–thaw cycles in mesocosms
Authors: Goldberg Stefanie D. , Muhr Jan , Borken Werner , Gebauer Gerhard 
Published: September 2008

AbstractFor this century, an increasing frequency of extreme meteorological boundary conditions is expected, presumably resulting in a changing frequency of freezing and thawing of soils in higher‐elevation areas. Our current knowledge about the effects of these events on trace‐gas emissions from soils is scarce. In this study, the effects of freeze–thaw events on the fluxes of the trace gases CO2, N2O, and NO between soil and atmosphere were investigated in a laboratory experiment. Undisturbed soil columns were collected from a mature Norway spruce forest in the “Fichtelgebirge”, SE Germany. The influence of freezing temperatures (–3°C, –8°C, –13°C) on gas fluxes was studied during the thawing periods (+5°C) in three freeze–thaw cycles (FTCs) and compared to unfrozen controls (+5°C).Two different types of soil columns were examined in parallel—one consisting of O layer only (O columns) and one composed of O layer and mineral soil horizons (O+M columns)—to quantify the contribution of the organic layer and the top mineral soil to the production or consumption of these trace gases.During the thawing period, we observed increasing emissions of CO2, N2O, and NO from the spruce forest soil, but the cumulative emissions of these gases did mostly not exceed the level of the controls. The results show that the O layers were mainly involved in the gas production. Severe soil frost increased CO2 fluxes during soil thawing, whereas repetition of the freeze–thaw events decreased CO2 fluxes from the thawing soil. Fluxes of N2O and NO were neither influenced by freezing temperature nor by freeze–thaw repetition.Stable‐isotope analysis indicated that denitrification was mostly responsible for the N2O production in the FTC columns. Furthermore, isotope data demonstrated a consumption of N2O through microbial denitrification to N2. It was further shown, that production of N2O also occurred in the mineral horizons. The NO emissions were mainly driven by increasing soil temperature during thawing. In this freeze–thaw experiment up to 20 times higher NO than N2O fluxes were recorded. Our results suggest that topsoil thawing has little potential to increase the emissions of CO2, N2O, and NO in spruce forest soils.
Separation of Parent Homopolymers from Diblock Copolymers by Liquid Chromatography under Limiting Conditions of Desorption, 2 ‐ Optimization of Experimental Arrangement
Authors: Berek Dušan 
Published: September 2008

AbstractThe experimental arrangement for liquid chromatography under limiting conditions of desorption was optimized, aiming at separation of the parent homopolymers from diblock copolymers. Measurements with the block copolymer PS‐b‐PMMA have confirmed that the method enables fast and efficient separation of both parent homopolymers PS and PMMA from the copolymers in a single run. The new experimental set‐up also allows the separation of potentially present low molecular or oligomeric admixtures from the polymeric constituents of sample. The peak broadening of the non‐retained macromolecules has been suppressed. The sample recovery is high and can be easily checked by the injection of a large volume of an appropriate displacer.magnified image
Enantiomeric differentiation of oxygenated p‐menthane derivatives by 13C NMR using Yb(hfc)3
Authors: Lanfranchi Don Antoine , Blanc Marie‐Cécile , Vellutini Muriel , Bradesi Pascale , Casanova Joseph , Tomi Félix 
Published: September 2008

AbstractThe 13C NMR behaviour of 21 p‐menthanic terpene bearing an oxygenated function (alcohol, ketone, acetate) was examined in the presence of a chiral lanthanide shift reagent (Yb(hfc)3). For each monocyclic compound, we measured the lanthanide‐induced shift (LIS) on the signals of the carbons and the splitting of signals allowing the enantiomeric differentiation. Some general features were found about their LIS behaviour: experimental data establishing distinct patterns for carvomenthone‐like compounds and menthone‐like compounds. The enantiomeric splitting was observed for the majority of signals in the spectrum of each compound. In the case of alcohols and acetates, the influence of the relative stereochemistry (cis vs trans) of isopropyl(ene) and the binding function was discussed. Copyright © 2008 John Wiley & Sons, Ltd.
The reaction of nitrosodicyclohexylamine with organolithiums
Authors: Vázquez Alvaro J. , Rodríguez Cristian , Nudelman N. Sbarbati 
Published: September 2008

AbstractThe detailed study of the reaction of N‐nitrosamines with organolithium compounds, under different reaction conditions, allowed the development of a useful methodology for the synthesis of substituted hydrazones and trialkyl hydrazines. The reaction proved to be very sensitive to the reaction conditions, and different main products can be obtained by fine tuning of several variables. With the purpose of searching into the reaction mechanism, a careful isolation, characterization, and quantitative determination of several minor products was carried out. N,N‐ dicyclohexylamine, N‐cyclohexylidencyclohexyl amine, and N,N,N′‐dicyclohexylalkylhydrazines, were the main side products identified after the work up of the reaction mixtures. With the same aim, the kinetics of the reaction of N‐nitrosodicyclohexylamine with n‐BuLi, was determined at temperatures in the range 0 °C room temperature. Under the conditions leading to the trialkyl hydrazine, the results show an abrupt slowdown of the reaction rate, after a short reaction time. This result, together with other observations, such as the recovering of hydrazone even when using high [RLi], is indicative of equilibrium involving different species in the reaction mixture. The isolation of reduction products, as well as additional experiments carried out with lithium dialkylamides and NO, allowed suggestion of an overall mechanistic scheme for the complex consecutive and parallel reactions, that is consistent with the afforded evidences. Copyright © 2008 John Wiley & Sons, Ltd.
Watsu approach for improving spasticity and ambulatory function in hemiparetic patients with stroke
Authors: Chon Seung Chul , Oh Duck Won , Shim Jae Hun 
Published: September 2008

AbstractBackground and Purpose. This study reports the effect of Watsu as rehabilitation method for hemiparetic patients with stroke. Method. Watsu consisted of 40 treatment sessions for 8 weeks, delivered underwater or at water surface level, it applied in three patients. Outcome measures included tools for assessing spasticity and ambulatory function. Results. All patients showed decreased scores in the TAS and RVGA after Watsu application. Conclusions. Watsu was helpful in controlling spasticity and improving ambulatory function of the patients with hemiparesis. Copyright © 2008 John Wiley & Sons, Ltd.
Crystal structure of a 1.6‐hexanediol bound tetrameric form of Escherichia coli Lac‐repressor refined to 2.1 Å resolution
Authors: Stenberg Kaj A. E. , Vihinen Mauno 
Published: September 2008

AbstractWe report the structure of a novel tetrameric form of the lactose repressor (LacI) protein from Escherichia coli refined to 2.1 Å resolution. The tetramer is bound to 1.6‐hexanediol present in the crystallization solution and the final Rfree for the structure is 0.201. The structure confirms previously reported structures on the monomer level. However, the tetramer is much more densely packed. This adds a new level of complexity to the interpretation of mutational effects and challenges details in the current model for LacI function. Several amino acids, previously associated with changes in function but unexplained at the structural level, appear in a new structural context in this tetramer which provides new implications for their function. Proteins 2009. © 2008 Wiley‐Liss, Inc.