bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantification of toluene dioxygenase induction and kinetic modeling of TCE cometabolism by Pseudomonas putida TVA8
Authors: Shingleton J.T. , Applegate B.A. , Baker A.J. , Sayler G.S. , Bienkowski P.R. 
Published: August 2002

AbstractAs measured by the toluene‐induced bioluminescent response of Pseudomonas putida TVA8 in batch experiments, toluene dioxygenase (Tod) enzyme activities are dependent on toluene concentration between 0 and 30 mg/L. To provide a measure of the Tod activity for use in Michaelis‐Menten competitive‐inhibition kinetics, a correlation between toluene concentration and induced Tod activity as measured by an induced bioluminescent response of P. putida TVA8 is presented as a nondimensional Tod activity parameter. A packed‐bed, radial‐flow bioreactor (RFB) using the bioreporter P. putida TVA8A serves as the model system for studying the effect of the enzyme activity parameter on model predictions of vapor‐phase toluene oxidation and trichloroethylene (TCE) cometabolism. Mass balances were performed on a differential section of the RFB to describe the radial transport of vapor‐phase toluene and TCE through a bulk gas phase and the concomitant biological reaction in a stationary biofilm phase. The finite‐element Galerkin weak‐statement formulation with first‐order basis functions was used to find the optimum solution to the highly nonlinear, coupled equations. For this RFB system with toluene concentrations less than 1 mg/L in the bulk gas phase, the Tod activity parameter enables accurate predictions of steady‐state TCE degradation rate (0.27 μg TCE/min). © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 76: 341–350, 2001.
Effects of furfural on anaerobic continuous cultivation of Saccharomyces cerevisiae
Authors: Horváth Ilona Sárvári , Taherzadeh Mohammad J. , Niklasson Claes , Lidén Gunnar 
Published: August 2002

AbstractFurfural is an important inhibitor of yeast metabolism in lignocellulose‐derived substrates. The effect of furfural on the physiology of Saccharomyces cerevisiae CBS 8066 was investigated using anaerobic continuous cultivations. Experiments were performed with furfural in the feed medium (up to 8.3 g/L) using three different dilution rates (0.095, 0.190, and 0.315 h−1). The measured concentration of furfural was low (< 0.1 g/L) at all steady states obtained. However, it was not possible to achieve a steady state at a specific conversion rate of furfural, qf, higher than approximately 0.15 g/g·h. An increased furfural concentration in the feed caused a decrease in the steady‐state glycerol yield. This agreed well with the decreased need for glycerol production as a way to regenerate NAD+, i.e., to function as a redox sink because furfural was reduced to furfuryl alcohol. Transient experiments were also performed by pulse addition of furfural directly into the fermentor. In contrast to the situation at steady‐state conditions, both glycerol and furfuryl alcohol yields increased after pulse addition of furfural to the culture. Furthermore, the maximum specific conversion rate of furfural (0.6 g/g·h) in dynamic experiments was significantly higher than what was attainable in the chemostat experiments. The dynamic furfural conversion could be described by the use of a simple Michaelis–Menten‐type kinetic model. Also furfural conversion under steady‐state conditions could be explained by a Michaelis–Menten‐type kinetic model, but with a higher affinity and a lower maximum conversion rate. This indicated the presence of an additional component with a higher affinity, but lower maximum capacity, either in the transport system or in the conversion system of furfural. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 540–549, 2001.
Electric field induced desorption of bacteria from a conditioning film covered substratum
Authors: Poortinga Albert T. , Smit Jelly , van der Mei Henny C. , Busscher Henk J. 
Published: August 2002

AbstractDesorption of three oral bacterial strains from a salivary conditioning film on an indium tin oxide electrode during application of a positive (bacterial adhesion to the anode) or a negative electric current was studied in a parallel plate flow chamber. Bacterial adhesion was from a flowing suspension of high ionic strength, after which the bacterial suspension was replaced by a low ionic strength solution without bacteria and currents ranging from −800 to +800 μA were applied. Streptococcus oralis J22 desorbed during application of a positive and negative electric current with a desorption probability that increased with increasing electric current. Two actinomyces strains, however, could not be stimulated to desorb by the electric currents applied. The desorption forces acting on adhering bacteria are electroosmotic in origin and working parallel to the electrode surface in case of a positive current, whereas they are electrophoretic and electrostatic in origin and working perpendicular to the surface in case of a negative current. By comparison of the effect of positive and negative electric currents, it can be concluded that parallel forces are more effective in stimulating bacterial desorption than perpendicular forces. The results of this study point to a new pathway of cleaning industrial and biomedical surfaces without the use of detergents or biocides. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 76: 395–399, 2001.
Metabolic flux analysis for succinic acid production by recombinant Escherichia coli with amplified malic enzyme activity
Authors: Hong Soon Ho , Lee Sang Yup 
Published: August 2002

AbstractA pfl ldhA double mutant Escherichia coli strain NZN111 was used to produce succinic acid by overexpressing the E. coli malic enzyme. Escherichia coli strain NZN111 harboring pTrcML produced 6 and 8 g/L of succinic acid from 20 g/L of glucose in flask culture at 37°C and 30°C, respectively. When NZN111(pTrcML) was cultured at 30°C with intermittent glucose feeding the final succinic acid concentration obtained was 9.5 g/L and the ratio of succinic acid to acetic acid was 13:1. This system could not be analyzed by conventional metabolic flux analysis techniques, since some pyruvate and succinic acid were accumulated intracellularly. Therefore, a new flux analysis method was proposed by introducing intracellular pyruvate and succinic acid pools. By this new method the concentrations of intracellular metabolites were successfully predicted and the differences between the measured and calculated reaction rates could be considerably reduced. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 89–95, 2001.
Prediction of the pilot‐scale recovery of a recombinant yeast enzyme using integrated models
Authors: Varga E. G. , Titchener‐Hooker N. J. , Dunnill P. 
Published: August 2002

AbstractThis article describes the rapid prediction of recovery process performance for a new recombinant enzyme product on the basis of a broad portfolio of computer models and highly targeted experimentation. A process model for the recombinant system was generated by linking unit operation models in an integrated fashion, with required parameter estimation and physical property determination accomplished using data from scale‐down studies. This enabled the generic modeling framework established for processing of a natural enzyme from bakers' yeast to be applied. An experimental study of the same operations at the pilot scale showed that the process model gave a conservative prediction of recombinant enzyme recovery. The model successfully captured interactions leading to a low overall product yield and indicated the need for further study of precipitate breakage in the feed zone of a disc stack centrifuge in order to improve performance. The utility of scale‐down units as an aid to fast model generation and the advantage of integrating computer modeling and scale‐down studies to accelerate bioprocess development are highlighted. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 96–107, 2001.
Performance of batch membrane reactor: Glycerol‐3‐phosphate synthesis coupled with adenosine triphosphate regeneration
Authors: Li Tao , Yeh Henry , Kim Ji‐Hyeon , Ryu Dewey D. Y. 
Published: August 2002

AbstractGlycerol‐3‐phosphate (G3P) was synthesized from glycerol using glycerol kinase (GK). This reaction requires adenosine triphosphate (ATP) and was coupled with the ATP regeneration reaction using acetate kinase (AK) in a batch‐operated ultrafiltration hollow‐fiber reactor. By taking into consideration the dynamic nature of the bioreactor performance under non–steady‐state conditions, a model for the performance of a batch membrane reactor for G3P synthesis coupled with ATP regeneration was developed and studied. The simulation results showed good agreement with the experimental results. The simulation studies have provided some insight into the process dynamics of the coupled reactions in the reactor system studied. For the reactor operational model used, in which the enzymes are retained in the shell side and the substrates are also initially placed in the shell side, it was found that the substrate concentration in the lumen side increased to a level higher than that in the shell side, and a backdiffusion occurred from the lumen side to the shell side during reactor operation. The ratio of the reaction rate to diffusion rate goes through a sharp peak during the time that the direction of diffusion is reversed. For another reactor operational model, in which the substrates were initially placed in the lumen side and enzymes were retained in the shell side, it was found that the rate‐controlling step between the reaction and diffusion was switched during the reactor operation. Initially, the reaction rate increased while the diffusion rate was high and the substrate concentrations increased in the shell side. The ratio of reaction rate to diffusion rate increased to a maximum and remained at a constant level as the diffusion rate decreased to a low level due to the nonlinear characteristics of mass transfer process. This study provides information that is useful for optimization of batch membrane enzyme reactor operation and for a fed‐batch‐type process with an intermittent feeding strategy for efficient use of substrates. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 326–334, 2001.
Towards more active biocatalysts in organic media: Increasing the activity of salt‐activated enzymes
Authors: Ru Michael T. , Wu Kahn C. , Lindsay John P. , Dordick Jonathan S. , Reimer Jeffrey A. , Clark Douglas S. 
Published: August 2002

AbstractThe activation of freeze‐dried subtilisin Carlsberg (SC) in hexane has been systematically studied and partially optimized with respect to the freezing method, the addition of inorganic salts and lyoprotectants, the initial concentration and final weight percent of additives, and the amount of water added to the organic solvent. Activity and water content were found to correlate directly with the kosmotropicity of the activating salt (kosmotropic salts bind water molecules strongly relative to the strength of water‐water interactions in bulk solution). Combinations of kosmotropic salts with known lyoprotectants such as poly(ethylene glycol) (PEG) and sugars did not yield an appreciably more active catalyst. However, the combination of the kosmotropic sodium acetate with the strongly buffering sodium carbonate activated the enzyme more than the individual additives alone. Enzyme activity was enhanced further by the addition of small amounts of water to the organic solvent. Under optimal conditions, enzyme activity in hexane was improved over 27,000‐fold relative to the salt‐free enzyme, reaching a catalytic efficiency that was within one order of magnitude of kcat/Km for hydrolysis of the same substrate in aqueous buffer. Further activation to attain even higher catalytic efficiencies may be possible with additional optimization. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 187–196, 2001.
Estimation of steady‐state culture characteristics during acceleration‐stats with yeasts
Authors: van der Sluis Catrinus , Westerink Brenda H. , Dijkstal Maikel M. , Castelein Sipke J. , van Boxtel Antonius J.B. , Giuseppin Marco L.F. , Tramper Johannes , Wijffels René H. 
Published: August 2002

AbstractSteady‐state culture characteristics are usually determined in chemostat cultivations, which are very time‐consuming. In contrast, acceleration‐stat (A‐stat) cultivations in which the dilution rate is continuously changed with a constant acceleration rate are not so time‐consuming, especially at high acceleration rates. Therefore, the A‐stat could be advantageous to use instead of the chemostat. However, the highest acceleration rate, meaning the fastest A‐stat that can be applied for estimating steady‐state culture characteristics, is not known yet. Experimental results obtained with Zygosaccharomyces rouxii, an important yeast in soy sauce processes, showed that the culture characteristics during the A‐stat with an acceleration rate of 0.001 h−2 were roughly comparable to those of the chemostat. For higher acceleration rates the deviation between the culture characteristics in the A‐stat and those in the chemostat obtained at the same dilution rate generally started to increase. The source of these deviations was examined by simulation for Saccharomyces cerevisiae. The simulations demonstrated that this deviation was not only dependent on the metabolic adaptation rate of the yeast, but also on the rate of change in environmental substrate concentrations during A‐stats. From this work, it was concluded that an A‐stat with an acceleration rate of 0.001 h−2 is attractive to be used instead of chemostat whenever a rough estimation of steady‐state culture characteristics is acceptable. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 267–275, 2001.
Managing environmental risk in existing light industrial estates
Authors: Jayne Michael Ross 
Published: August 2002

AbstractIn order to optimize the role of light industrial estates in the environment, it is desirable to follow the principles of ecological modernization and factor the environmental considerations into the development process. This is not possible with existing estates, where a different approach must be taken. This paper examines research conducted at five light industrial estates and considers the role of the landlord in determining an alternative strategy. The results suggest that occupiers are still not taking all the reasonable steps available to them in order to mitigate their potential for environmental damage, nor are they fully exploiting the opportunities that exist for environmental improvements. Landlords of light industrial estates have long term interests in property and, consequently, have a role in ensuring that existing estates are better managed from an environmental point of view. As such landlords have the potential to contribute to the process of ecological modernization. Copyright © 2001 John Wiley & Sons, Ltd and ERP Environment
Unusual origin and course of the left pulmonary artery
Authors: Gerlis Leon M. , Anderson Robert H. 
Published: August 2002

AbstractAn infant with a cardiac murmur was found to have a patent arterial duct and an anomalous left pulmonary artery. The duct was surgically ligated at the age of 8 months, and she remained free of cardiac or respiratory symptoms up to her death at 6 years from an unrelated intestinal condition. An anomaly was discovered at post mortem examination; the left pulmonary artery arose from the right pulmonary artery and passed behind the trachea to enter the left lung. We describe and illustrate the anatomic features of this well‐recognized entity, discuss the embryological substrate, and refer to the clinical implications. Clin. Anat. 5:373–378, 2001. © 2001 Wiley‐Liss, Inc.
Meeting the training needs of GP registrars in child abuse and neglect
Authors: Bannon Michael J. , Carter Yvonne H. , Jackson Neil R. , Pace Melanie , Thorne Wendy 
Published: August 2002

AbstractA questionnaire survey undertaken among general practitioner registrars in North Thames in 1998 revealed significant deficiencies in their child protection training. A minority expressed confidence at the prospect of dealing with child protection cases in the future. A new, interactive training package was subsequently developed and delivered to a sample of GP registrars in Northeast Thames in 1999. Preliminary evaluation confirmed that the new training material was sensitive to the needs of recipients and levels of perceived confidence with participation in child protection work were increased. Further work is needed to develop the package and to oversee its successful incorporation into general practitioner vocational training. Copyright © 2001 John Wiley & Sons, Ltd.
Closure of the femoral vein puncture site after transcatheter procedures using Angio‐Seal
Authors: Coto Humberto A. 
Published: August 2002

AbstractThe use of anchor‐based, collagen‐derived vascular sealing devices in femoral vein punctures during right and left heart catheterizations or coronary interventions necessitating venous access for temporary pacemaker or hemodynamic monitoring has not been studied. We hypothesized that using these devices in the femoral vein would be practical and reliable. One hundred and ten consecutive patients undergoing right and left heart catheterization (56 patients, 51%) or coronary intervention (54 patients, 49%) were included in this study. Forty‐five of the interventions received IIb/IIIa inhibitors in combination with heparin, enoxaparin, aspirin, and clopidogrel. The Angio‐Seal device was successfully deployed in the femoral vein in all patients, whereas 93 (85%) received arterial Angio‐Seal, 8 received Perclose, and 9 (8%) had manual pressure or a Fem‐Stop applied to control arterial bleeding after deployment. We conclude that in patients undergoing transcatheter procedures requiring venous access, the use of an 8 Fr Angio‐Seal to seal the femoral vein is safe and feasible. Cathet Cardiovasc Intervent 2002;55:16–19. © 2002 Wiley‐Liss, Inc.
Comparison of myocardial fractional flow reserve and intravascular ultrasound for the assessment of slotted‐tube stents
Authors: Katritsis Demosthenes G. , Ioannidis John P.A. , Korovesis Socrates , Giazitzoglou Eleftherios , Parissis John , Kalivas Pericles , Webb‐Peploe Michael M. 
Published: August 2002

AbstractIntravascular ultrasound (IVUS) and myocardial fractional flow reserve (FFR) have been reported to provide similar results for assessment of coil stent deployment. Their relative value in slotted‐tube stents has not been investigated. Fourteen patients subjected to coronary angioplasty and IVUS‐guided elective stenting with a slotted‐tube stent underwent IVUS assessment and FFR measurement following stent implantation at inflation pressures of 12 and 18 atm. FFR values (mean ± SD) preangioplasty, postangioplasty, and poststenting at 12 atm and 18 atm, were 0.58 ± 0.07, 0.83 ± 0.05, 0.94 ± 0.02, and 0.94 ± 0.02, respectively. After inflation at 12 atm, the area under the receiver operating characteristic (ROC) curve for the concordance of IVUS and FFR measurements was 0.89 (P = 0.02). Six patients had either an abnormal IVUS (n = 2) or FFR < 0.94 (n = 1) or both abnormal IVUS and FFR < 0.94 (n = 3) after the first inflation and had a second inflation at 18 atm. The area under the ROC curve for the concordance between IVUS and FFR final measurements was 0.855 (P = 0.10). Perfect concordance between IVUS and FFR was seen only for FFR values less than 0.91 or larger than 0.94. Overall, IVUS and FFR have substantial concordance with respect to slotted‐tube stent deployment. However, FFR values between 0.91 and 0.94 after inflation are difficult to interpret. Cathet Cardiovasc Intervent 2001;52:322–326. © 2001 Wiley‐Liss, Inc.
Percutaneous transluminal angioplasty of ostial lesions of internal mammary artery grafts
Authors: Jacq Laureut , Lancelin Bernard , Brenot Philippe , Caussin Christophe 
Published: August 2002

AbstractThe internal mammary artery (IMA) is currently the best graft for coronary bypass surgery and is therefore preferentially anastomosed to major arteries, usually the left anterior descending (LAD) artery. This graft may develop a stenosis, most often at the distal anastomosis. Ostial stenoses are rare and their pathophysiology uncertain. While angioplasty of distal anastomotic lesions provides adequate results, the very small number of published cases of angioplasty of ostial lesions explains the lack of knowledge on results of this type of procedure. The authors report six procedures of this type on five patients, including two with stenting. The primary success rate was 100%, with only one hospital complication in the form of pulmonary edema. Mean follow‐up for 35 months revealed one sudden death due to probable restenosis, another death 3 years after angioplasty from rapid fatal shock without complementary investigation, and one case of unstable angina secondary to intrastent restenosis. These results suggest that this type of angioplasty is technically feasible with low risk, and that the restenosis rate seems relatively high, potentially presenting as sudden death, in the same way as unprotected dilatation of the native left main artery. A very close clinical follow‐up of these patients is therefore necessary, with angiographic control in case of suspected ischemia. Cathet Cardiovasc Intervent 2001;52:368–372. © 2001 Wiley‐Liss, Inc.
Use of fractional flow reserve in the treatment of a calcific bifurcation left anterior descending coronary stenosis with rotational atherectomy
Authors: Holmes David G. , Kern Morton J. 
Published: August 2002

AbstractWe report the results of an intervention in a high‐risk surgical patient undergoing rotational atherectomy in a bifurcating lesion. The use of fractional flow reserve (FFR) was especially helpful due to the inability to visualize clearly the angiographic anatomy both before and following intervention. Cathet Cardiovasc Intervent 2001;53:64–67. © 2001 Wiley‐Liss, Inc.
Thermography of human arterial system by means of new thermography catheters
Authors: Stefanadis Christodoulos , Toutouzas Konstantinos , Tsiamis Eleftherios , Vavuranakis Manolis , Kallikazaros Ioannis , Toutouzas Pavlos 
Published: August 2002

AbstractIn this case report, we present the first clinical application of three thermography catheters for temperature measurements in the coronary arteries, the aorta, and the femoral arteries. The entire procedure was performed successfully without complications. Larger clinical studies are required in order to examine the feasibility for the application of the aortic and the peripheral artery thermography catheters and the clinical significance of temperature measurements in these arteries. Cathet Cardiovasc Intervent 2001;54:51–58. © 2001 Wiley‐Liss, Inc.
Lactones. 6. Microbial lactonization of γ,δ‐epoxy esters
Authors: Olejniczak Teresa , Gawroński Jacek , Wawrzeńczyk Czesław 
Published: August 2002

AbstractThe ability of 19 microorganisms to perform the enantioselective lactonization of racemic γ,δ‐epoxy ester 3a and its 7‐methyl homolog 3b was checked. It was found that Rhodotorula rubra preferentialy transformed both substrates to (−)‐enantiomers of trans δ‐hydroxy‐γ‐lactones with ee 76% for 3a and 24% for 3b. The best efficiency (20–30%) and enantioselectivity (ee 60–100%) of formation of (−)‐γ‐hydroxy‐δ‐lactones 6a and 6b was observed for lactonization by Botrytis cinerea and Fusarium semitectum, respectively. Chirality 13:302–307, 2001. © 2001 Wiley‐Liss, Inc.