bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of isomaltooligosaccharides and oligodextrans in a recycle membrane bioreactor by the combined use of dextransucrase and dextranase
Authors: Goulas Athanasios K. , Cooper Julian M. , Grandison Alistair S. , Rastall Robert A. 
Published: November 2004

AbstractA recycle ultrafiltration membrane reactor was used to develop a continuous synthesis process for the production of isomaltooligosaccharides (IMO) from sucrose, using the enzymes dextransucrase and dextranase. A variety of membranes were tested and the parameters affecting reactor stability, productivity, and product molecular weight distribution were investigated. Enzyme inactivation in the reactor was reduced with the use of a non‐ionic surfactant but its use had severe adverse effects on the membrane pore size and porosity. During continuous isomaltooligosaccharide synthesis, dextransucrase inactivation was shown to occur as a result of the dextranase activity and it was dependent mainly on the substrate availability in the reactor and the hydrolytic activity of dextranase. Substrate and dextranase concentrations (50–200 mg/mL−1 and 10–30 U/mL−1, respectively) affected permeate fluxes, reactor productivity, and product average molecular weight. The oligodextrans and isomaltooligosaccharides formed had molecular weights lower than in batch synthesis reactions but they largely consisted of oligosaccharides with a degree of polymerization (DP) greater than 5, depending on the synthesis conditions. No significant rejection of the sugars formed was shown by the membranes and permeate flux was dependent on tangential flow velocity. © 2004 Wiley Periodicals, Inc.
Synergistic effect of shear stress and streptavidin‐biotin on the expression of endothelial vasodilator and cytoskeleton genes
Authors: Chan Bernard P. , Reichert William M. , Truskey George A. 
Published: November 2004

AbstractDual ligand treatment of streptavidin(SA)‐biotin and fibronectin (Fn) enhances the adhesion of endothelial cells (EC) onto synthetic surfaces and promotes the quiescent phenotype of adherent EC. The current study investigates the effect of the dual ligand on the expression of endothelial genes in static culture and under shear stress (4 h at 10 dynes/cm2). Expression of 23 genes in the classes of signaling, cytoskeleton/ECM, vasoregulation, and shear‐responsive were examined. Eight genes (argininosuccinate synthetase, K+ channel, TGFβ, Mn‐SOD, α‐tubulin, t‐PA, COX2, and eNOS) were significantly upregulated by shear stress. Two genes (caveolin‐1 and ET‐1) were downregulated by shear stress. Three genes (RhoA, elastin, α‐actinin) were upregulated by the dual ligand treatment in static culture, and four genes (FAK, elastin, COX2, and eNOS) were upregulated when the dual ligand and shear stress were applied simultaneously. Northern blot analyses on FAK, RhoA, elastin, and α‐actinin revealed similar results. The results suggest (1) the use of SA‐biotin to supplement EC adhesion enhances the integrity of the EC cytoskeleton by upregulating the expression of cytoskeleton/ECM genes, and (2) a likely relationship between the expression of cytoskeleton/ECM genes and the downstream events, such as the shear‐induced expression of eNOS and COX2 genes. Analyses presented in this study provide insights into the mechanism by which SA‐biotin‐supplemented EC mediate gene expression. © 2004 Wiley Periodicals, Inc.
Effective non‐viral leader for cap‐independent translation in a eukaryotic cell‐free system
Authors: Shaloiko L.A. , Granovsky I.E. , Ivashina T.V. , Ksenzenko V.N. , Shirokov V.A. , Spirin A.S. 
Published: November 2004

AbstractThe 61 nt 5′‐untranslated region (5′‐UTR) of mRNA encoding for a light‐emitting protein of hydroid polyp Obelia longissima, obelin, is shown to provide a high level of cap‐independent translation of heterologous mRNAs in cell‐free translation systems based on wheat germ extracts. The inhibition of translation typically observed when excess mRNA is present or produced in a eukaryotic system (the so‐called self‐inhibition phenomenon) is found abated with mRNA constructs carrying the obelin mRNA leader. The role of the sequestration of a limiting initiation factor, probably eIF4F, in the self‐inhibition phenomenon and the possible independence of the obelin mRNA leader from eIF4F are discussed. We propose the obelin mRNA leader be used for effective cap‐independent translation in eukaryotic cell‐free systems, including combined transcription‐translation systems with uncontrolled phage polymerase‐catalyzed accumulation of mRNA. © 2004 Wiley Periodicals, Inc.
Strain improvement and metabolic flux analysis in the wild‐type and a mutant Lactobacillus lactis strain for L(+)‐lactic acid production
Authors: Bai Dong‐Mei , Zhao Xue‐Ming , Li Xin‐Gang , Xu Shi‐Min 
Published: November 2004

AbstractThe effects of initial glucose concentration and calcium lactate concentration on the lactic acid production by the parent strain, Lactobacillus lactis BME5‐18, were studied. The results of the experiments indicated that glucose and lactate repressed the cell growth and the lactic acid production by Lactobacillus lactis BME5‐18. A l(+)‐lactic acid overproducing strain, Lactobacillus lactis BME5‐18M, was screened by mutagenizing the parent strain with ultraviolet (UV) light irradiation and selecting the high glucose and lactate calcium concentration repression resistant mutant. Starting with a concentration of 100g L−1 glucose, the mutant produced 98.6 g L−1 lactic acid after 60 h in flasks, 73.9% higher than that of the parent strain. The l(+)‐lactic acid purity was 98.1% by weight based on the amount of total lactic acid. The culture of the parent strain could not be analyzed well by conventional metabolic flux analysis techniques, since some pyruvate were accumulated intracellularly. Therefore, a revised flux analysis method was proposed by introducing intracellular pyruvate pool. Further studies demonstrate that there is a high level of NADH oxidase activity (12.11 mmol mg−1 min−1) in the parent strain. The molecular mechanisms of the strain improvement were proposed, i.e., the high level of NADH oxidase activity was eliminated and the uptake rate of glucose was increased from 82.1 C‐mmol (g DW h)−1 to 98.9 C‐mmol (g DW h)−1 by mutagenizing the parent strain with UV, and therefore the mutant strain converts mostly pyruvate to lactic acid with a higher productivity (1.76 g L−1h−1) than the parent strain (0.95 g L−1h−1). © 2004 Wiley Periodicals, Inc.
Bacterial P450‐catalyzed polyketide hydroxylation on a microfluidic platform
Authors: Srinivasan Aravind , Bach Horacio , Sherman David H. , Dordick Jonathan S. 
Published: November 2004

AbstractThe incorporation of a multicomponent, cofactor‐dependant P450 into a microfluidic biochip is demonstrated. The PikC hydroxylase Streptomyces venezuelae was incorporated into a PDMS‐based microfluidic channel. The enzyme was immobilized to Ni‐NTA agarose beads via in situ attachment following the addition of the beads to the microchannel. The enzyme loading was ∼6 μg per mg of beads resulting in a microchannel loading of 10.7 mg/mL. This high enzyme loading enabled the rapid hydroxylation of the macrolide YC‐17 to methymycin and neomethymycin in about equal amounts with a conversion of >90% at a flow rate of 70 nL/min. This high reactivity allowed rapid hydroxylation reactions to be performed with short residence times, which is critical for complex enzymes with limited inherent stability. © 2004 Wiley Periodicals, Inc.
Effects of a selective cyclo-oxygenase 2 inhibitor on colonic anastomotic and skin wound integrity
Authors: Cahill R A , Sheehan K M , Scanlon R W , Murray F E , Kay E W , Redmond H P 
Published: November 2004

Abstract

Background
Selective inhibitors of inducible cyclo-oxygenase (COX-2) are of potential benefit in the perioperative period for both their analgesic and, perhaps, antineoplastic actions. However, their effects on laparotomy and intestinal wound healing are unknown.

Methods
Forty adult Sprague–Dawley rats underwent laparotomy, descending colonic transection and handsewn reanastomosis. The animals were randomized to receive either a selective COX-2 inhibitor (rofecoxib, 10 mg/kg) or an equal volume of water by gavage before operation and then daily after surgery. Animals were killed after 3 or 7 days, and their wounds were evaluated by means of tensiometry (skin and colonic wounds) and bursting pressure measurement (colonic anastomoses). In addition, haematoxylin and eosin-stained intestinal sections were examined and scored by a blinded independent observer.

Results
Five animals that received rofecoxib had anastomotic leaks by day 7 compared with none in the control group (P = 0·048). Intact colonic suture lines were also significantly weaker in this group (tensile strength at day 3, P = 0·043; bursting pressure on days 3 and 7, both P = 0·019). Skin wound strengths were similar in the two groups at both time points.

Conclusion
Although beneficial in the treatment of pathological inflammation, selective COX-2 inhibitors may adversely affect colonic anastomotic healing.
Autopsy findings from 111 deaths in the 1999 Athens earthquake as a basis for auditing the emergency response
Authors: Papadopoulos I N , Kanakaris N , Triantafillidis A , Stefanakos J , Kainourgios A , Leukidis C 
Published: November 2004

Abstract

Background
The aim of the study was to assess the emergency response to an earthquake.

Methods
This retrospective study, based on formal autopsy findings from 111 earthquake-related deaths, evaluated demographic data, circumstances of death, rescue time, mechanisms of injury, causes of death, Abbreviated Injury Scale (AIS 90) and Injury Severity Score (ISS) values, vital functions, co-morbidity and preventable deaths.

Results
The median extrication time for 99 of 102 victims buried or trapped in collapsed buildings was 2·1 (range 0·1–7·8) days. Deaths were cause by blunt injuries, asphyxia and myocardial infarction. Injuries impaired the airway, breathing, circulation, and brain or spinal functions in 10·5, 61·9, 46·6 and 57·1 per cent of the victims respectively. The 105 injured victims were classified into three main categories. The first comprised 36 victims (34·3 per cent) with injuries not compatible with life (ISS 75), the second included 38 victims (36·2 per cent) who suffered life-threatening injuries (ISS 9–74) but had no evidence of asphyxia, and the third category contained 31 victims (29·5 per cent) with findings of asphyxia and an ISS of 1–18. The reviewers concluded that 13 trauma-related deaths and 31 deaths from asphyxia were potentially preventable.

Conclusion
A method based on detailed evaluation of deaths provided information with which to audit the emergency response to an earthquake.
Effects of warm-up on exercise capacity, platelet activation and platelet–leucocyte aggregation in patients with claudication
Authors: Pasupathy S , Naseem K M , Homer-Vanniasinkam S 
Published: November 2004

Abstract

Background
The effects of exercise and warm-up were investigated in patients with claudication.

Methods
This case–control crossover study involved two treadmill exercise tests, one preceded by a warm-up. Exercise continued until maximal leg pain (patients with claudication) or exhaustion (controls). Blood was taken before, and 5 and 60 min after exercise for flow cytometric analysis of platelet activation and platelet–leucocyte aggregation.

Results
Both cohorts (eight patients with claudication of median age 63 years and eight healthy controls of median age 63·5 years) demonstrated improvement in exercise capacity after warm-up (13·1 per cent, P = 0·012 and 15·6 per cent, P = 0·008 respectively). Platelet activation increased after exercise in patients with claudication (fibrinogen binding: 1·11 per cent before exercise versus 2·63 per cent after exercise, P = 0·008; P-selectin: 0·68 versus 1·11 per cent, P = 0·028). Neither agonist stimulation nor warm-up altered this trend. Platelet–leucocyte (PLA) and platelet–neutrophil (PNA) aggregation were similarly increased immediately after exercise in patients with claudication (PLA: 7·6 versus 13·0 per cent, P = 0·004; PNA: 6·8 versus 10·2 per cent, P = 0·012). These remained high 60 min after exercise only in patients with claudication, but recovered to baseline levels when preceded by warm-up. Warm-up significantly desensitized PNA after stimulation with 10 µmol/l adenosine 5′-diphosphate at all time points.

Conclusion
Warm-up increased the exercise capacity of patients with claudication. Exercise induced a thromboinflammatory response, with PLA and PNA persistently increased after 60 min in patients with claudication, an effect diminished after warm-up.
Implementing chemicals policy: leaders or laggards?
Authors: Richards J. P. , Glegg G. A. , Cullinane S. 
Published: November 2004

AbstractPrioritization of regulatory agency resources remains a key issue in the management of industrial pollution. This is likely to become increasingly important as a new EC chemicals policy is implemented and measures are introduced to achieve the OSPAR zero emissions target. The Environment Agency (England and Wales) has updated the Operator Pollution and Risk Assessment (OPRA) scheme, but it still includes no quantitative measurement of operator attitudes towards environmental regulation. This is important because regulated firms' attitudes are known to affect regulatory behaviour. This study explores the attitudes of environmental managers from 142 chemical sector companies regulated under Integrated Pollution Control. Analysis of responses from a questionnaire survey revealed a number of regulatory typologies. A ‘conservative’ cluster exhibited satisfaction with the current regulatory system and rejected change. ‘Progressive’ cluster members recognized shortcomings and welcomed change. This methodology could be used alongside OPRA to support decisions necessary to prioritize regulatory resources. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment.
Neutrophils from Brazilian patients with Graves' disease: some biochemical and functional aspects
Authors: Russo‐Carbolante E. M. S. , Polizzelo A. C. M. , Azzolini A. E. C. S. , Maciel L. M. Z. , Lucisano‐Valim Y. M. 
Published: November 2004

AbstractGraves' disease shows important systemic inflammatory complications and has been considered to be systemic autoimmune thyroid, skeletal muscle and connective tissue syndrome. Neutrophils participate in the pathophysiology of the two major immune and inflammatory manifestations of the disease, ophthalmopathy and myxedema, and may worsen the inflammatory picture. In this study we analysed some biochemical and functional aspects of neutrophils in Graves' disease patients to assess their participation in these processes. The results show that the complement and/or Fcγ receptor‐mediated oxygen radical production by neutrophils was increased when patient cells were compared with controls. However the percentage of cells expressing complement and IgG receptors and the per‐cell fluorescence, were similar, indicating that the increased oxidative burst was not due to an abnormal expression of mediating receptors. The production of hydrogen peroxide was also increased in hyperthyroid patient neutrophils as compared to controls. Conversely, antioxidant defences (superoxide dismutase activity and reduced glutathione content) in neutrophils from patients were not significantly different from healthy controls. The liberation of potent oxidative compounds together with the absence of adequate quenching of them by antioxidant mechanisms could be responsible for greater tissue damage in inflammatory conditions, as is the case in ophthalmopathy and myxedema patients. Considering our results and those of other workers, we encourage and suggest an associated antioxidant therapy to complement the conventional anti‐thyroid therapy, especially in obvious inflammatory cases and in individuals who smoke. Copyright © 2004 John Wiley & Sons, Ltd.
Analysis of Platinum Adducts with DNA Nucleotides and Nucleosides by Capillary Electrophoresis Coupled to ESI‐MS: Indications of Guanosine 5′‐Monophosphate O6–N7 Chelation
Authors: Warnke Ulrich , Rappel Christina , Meier Heiko , Kloft Charlotte , Galanski Mathea Sophia , Hartinger Christian G. , Keppler Bernhard K. , Jaehde Ulrich 
Published: November 2004

AbstractDNA is the ultimate target of platinum‐based anticancer therapy. Since the N7 of guanine is known to be the major binding site of cisplatin and its analogues, adduct formation with model nucleotides, especially 2′‐deoxyguanosine 5′‐monophosphate (dGMP), has been studied in detail. During the last few years a coupled capillary eletrophoresis/electrospray‐ionization mass spectrometry (CE/ESI‐MS) method has been advantageously used in order to separate and identify platinum adducts with nucleotides in submillimolar concentrations in aqueous solutions. Beside the bisadduct, [Pt(NH3)2(dNMP)2]2− (NMP=2′‐deoxynucleoside 5′‐monophosphate), and the well‐known monochloro and monohydroxo adducts, [Pt(NH3)2Cl(dNMP)]− and [Pt(NH3)2(dNMP)OH]−, respectively, a third kind of monoadduct species with a composition of [Pt(NH3)2(dNMP)]− can be separated by CE and detected through the m/z values measured with ESI‐MS. Different experimental setups indicate the existence of an O6–N7 chelate, whereas the formation of N7–αPO4 macrochelates or dinuclear species is unlikely. Additionally, offline MS experiments with 2′‐deoxyguanosine (dG) and stabilization of the controversially discussed O6–N7 chelate by oxidation with hydrogen peroxide support the assumption of the existence of O6–N7 chelation.
Function of lanGT3, a Glycosyltransferase Gene Involved in Landomycin A Biosynthesis
Authors: Luzhetskyy Andriy , Liu Tao , Fedoryshyn Marta , Ostash Bohdan , Fedorenko Viktor , Rohr Jürgen , Bechthold Andreas 
Published: November 2004

AbstractThe glycosyltransferase gene lanGT3, involved in the biosynthesis of the angucyclic antibiotic landomycin A, has been characterised by targeted gene deletion. A lanGT3 mutant was shown to produce landomycin E, which consists of a trisaccharide side chain attached to the polyketide moiety. Expression of lanGT3 in the mutant restored landomycin A production. Our results indicate that LanGT3 is responsible for the transfer of the fourth sugar during landomycin A biosynthesis.
Modified Oligonucleotides Containing Lithocholic Acid in Their Backbones: Their Enhanced Cellular Uptake and Their Mimicking of Hairpin Structures
Authors: Kim Su Jeong , Bang Eun‐Kyoung , Kwon Ho Jeong , Shim Joong Sup , Kim Byeang Hyean 
Published: November 2004

AbstractTheir enhanced cell permeability and their ability to mimic DNA structures make modified oligodeoxyribonucleotides (ODNs) very important substances for increasing our understanding of cell biology and for therapeutic applications. Lithocholic acid is a hydrophobic secondary bile acid that is a substrate of nuclear Pregnane X receptor (PXR). We designed and synthesized novel lithocholic acid‐based ODNs (L‐ODNs) by using a new phosphoramidite derived from lithocholic acid. By comparing data obtained from circular‐dichroism, melting‐point, and theoretical studies, we believe that these L‐ODNs adopt DNA hairpin structures. Furthermore, L‐ODNs have enhanced cellular uptake properties with respect to regular ODNs. To demonstrate their enhanced cell permeabilities, we carried out cellular uptake experiments of L‐ODNs in HeLa cells. By attaching fluorescein as a fluorescence label and using confocal microscopy, we observed that the permeability of L‐ODNs is much higher than that of natural ODNs.
Boiling Heat Transfer Enhancement of Water/Salt Mixtures on Roll‐Worked Enhanced Tubes in Compact Staggered Tube Bundles
Authors: Liu Z.‐H. , Qiu Y.‐H. 
Published: November 2004

AbstractAn experimental study was performed for the boiling heat transfer enhancement of water/salt mixtures on both plane and roll‐worked enhanced tubes in compact staggered tube‐bundle evaporators under atmospheric and increased pressure conditions. The effects of tube spacing, position of tubes, test pressure and salt‐water concentration on the boiling heat transfer characteristics in restricted spaces of compact tube bundles consisting of plane and roll‐worked tubes were investigated. The experimental results indicate that the single roll‐worked tubes in a bulk liquid have a greater boiling heat transfer promotion than the single plane tubes. For the plane tubes in compact tube bundles, the effect of tube spacing on the boiling heat transfer is very significant. The boiling heat transfer has a maximum enhancement when the optimum tube spacing is selected. For the roll‐worked tubes in compact bundles, the effect of tube spacing on the boiling heat transfer is also significant as the tube spacing is small. The boiling heat transfer still has a maximum value and a compound enhancement effect of the boiling heat transfer from both the optimum tube spacing and the surface treatment is observed for the enhanced tube bundles.
Reactor Modeling of Gas‐Phase Polymerization of Ethylene
Authors: Kiashemshaki A. , Mostoufi N. , Sotudeh‐Gharebagh R. , Pourmahdian S. 
Published: November 2004

AbstractA model is developed for evaluating the performance of industrial‐scale gas‐phase polyethylene production reactors. This model is able to predict the properties of the produced polymer for both linear low‐density and high‐density polyethylene grades. A pseudo‐homogeneous state was assumed in the fluidized bed reactor based on negligible heat and mass transfer resistances between the bubble and emulsion phases. The nonideal flow pattern in the fluidized bed reactor was described by the tanks‐in‐series model based on the information obtained in the literature. The kinetic model used in this work allows to predict the properties of the produced polymer. The presented model was compared with the actual data in terms of melt index and density and it was shown that there is a good agreement between the actual and calculated properties of the polymer. New correlations were developed to predict the melt index and density of polyethylene based on the operating conditions of the reactor and composition of the reactants in feed.
The Influence of the External Imprinted Flow Field on Capillary Instability Driven Jet Breakup
Authors: Fischer P. , Maruyama K. , Windhab E.J. 
Published: November 2004

AbstractThe breakup of a flowing liquid jet surrounded by a second flowing liquid is governed by capillary instabilities. These instabilities are caused by minor perturbations in the flow field that build up sinusoidal waves at the jet interface and eventually break it up. The phenomenon of such fatal wavelengths was described first by Lord Rayleigh and later extended by several authors to quiescent and flowing liquid‐liquid systems. The jet formation in a co‐flowing environment was only recently investigated. Originating from the forced breakup of liquid jets in air, this paper reports on the breakup mechanism of liquid jets surrounded by a fluid. By using different flow cells and consequently different flow profiles along the jet trajectory, the breakup mechanism given by the material and process parameters could be excited or suppressed. Two questions concerning droplet generation and the droplet size distribution are addressed: the suppression of the fatal wavelength in transient flow fields and the use of external flow fields to support the fatal wavelength.
Modeling of the Wall Effect in Packed Bed Adsorption
Authors: Kwapinski W. , Winterberg M. , Tsotsas E. , Mewes D. 
Published: November 2004

AbstractA model developed for catalytic packed bed reactors and consistently accounting for the influence of the tube wall on porosity, flow and transport phenomena is used in order to simulate the operation of packed bed adsorbers. By comparison of simulation results with reduced versions of the model the influence of the wall on the adsorber performance is worked out and found to be major at low ratios between tube and particle diameter. The interaction between maldistribution, thermal effects and intraparticle resistances in such adsorber tubes is discussed.