bluuebunny/crossref_metadata_2025 huggingface dataset:
Folate‐targeted imaging of activated macrophages in rats with adjuvant‐induced arthritis
Authors: Turk Mary Jo , Breur Gert J. , Widmer William R. , Paulos Chrystal M. , Xu Le‐Cun , Grote Lee Ann , Low Philip S.
Published: September 2002

Objective

To determine whether overexpression of the high‐affinity folate receptor (FR) on activated macrophages can be exploited to selectively target imaging agents to sites of inflammation in rats with adjuvant‐induced arthritis (AIA).

Methods

Folic acid was conjugated to a 99mTc chelator (the complex termed EC20), and its distribution was visualized using gamma scintigraphy in healthy rats, rats with AIA, and arthritic rats that had been depleted of macrophages. To confirm that uptake was mediated by the FR, excess folic acid competition studies were conducted, and tissue FR levels were quantitated using a radioligand binding assay. Flow cytometry was also used to investigate uptake of folate conjugates into macrophages of both arthritic and healthy rats.

Results

EC20 concentrated in the arthritic extremities of diseased rats but not in the extremities of healthy rats. The intensity of images of affected tissues was greatly reduced in the presence of excess competing folic acid. The livers and spleens of arthritic animals also showed enhanced uptake of EC20 and increased levels of FR. Depletion of macrophages from arthritic animals reduced tissue FR content and concomitantly abolished uptake of EC20. In addition, macrophages isolated from livers of rats with AIA exhibited a significantly higher binding capacity for folate conjugates than did macrophages obtained from healthy rats.

Conclusion

Although EC20 is currently undergoing clinical evaluation for use in the imaging of ovarian carcinomas, the present results suggest that it may also be useful for assaying the participation of activated macrophages in inflammatory processes such as rheumatoid arthritis.
Bone loss in patients with rheumatoid arthritis: Results from a population‐based cohort of 366 patients followed up for two years
Authors: Haugeberg Glenn , Ørstavik Ragnhild E. , Uhlig Till , Falch Jan A. , Halse Johan I. , Kvien Tore K.
Published: September 2002

Objective

To evaluate the extent of and risk factors for bone loss in a population‐based cohort of patients with rheumatoid arthritis (RA) receiving conventional health care.

Methods

In a longitudinal study, clinical data were collected and bone mineral density (BMD) measurements were performed at baseline and after 2 years. Dual‐energy x‐ray absorptiometry was used for hip and spine BMD measurements. At baseline, patients received advice about lifestyle adjustments and calcium and vitamin D supplementation; during the followup period they were treated with antirheumatic and bone‐sparing drugs, according to clinical judgment.

Results

After a mean ± SD of 2.2 ± 0.2 years, 366 (298 women, 68 men) of the 488 patients who were examined at baseline were reexamined. At that time, 47.9% were current users of corticosteroids and 37.0% were using antiresorptive drugs (hormone replacement therapy, bisphosphonates, or calcitonin). The mean BMD reduction was −0.64% in the femoral neck, −0.77% in the total hip, and −0.29% in the spine at L2‐4. BMD was increased at all measurement sites in current users of antiresorptive drugs (0.16–1.64%) but was decreased in patients using calcium and vitamin D alone (−1.99% to −1.39%) and in patients not using any osteoporosis treatment (−1.20% to −0.43%). Current use of corticosteroids was independently associated with increased risk for BMD loss in the total hip (odds ratio [OR] 2.63, 95% confidence interval [95% CI] 1.38–5.00) and spine at L2‐4 (OR 2.70, 95% CI 1.30–5.63), whereas current use of antiresorptive drugs was associated with decreased risk for bone loss in the total hip (OR 0.43, 95% CI 0.20–0.89).

Conclusion

Results of this population‐based, 2‐year followup study indicate that adequate management of patients with RA, addressing both the rheumatic disease and osteoporosis, protects against bone loss.
Flunisolide HFA vs flunisolide CFC: pharmacokinetic comparison in healthy volunteers
Authors: Nolting Arno , Sista Suryanarayana , Abramowitz Wattanaporn
Published: September 2002

Two preparations of flunisolide, an inhaled corticosteroid, were compared in a parallel, multiple‐dose study of 31 healthy volunteers. The new flunisolide preparation substitutes hydrofluoroalkane (HFA) for chlorofluorocarbon (CFC) as a propellant and incorporates a spacer into its pressurized metered‐dose inhaler (pMDI). In this study, subjects were randomly assigned to receive flunisolide CFC 1000 µg bid; flunisolide HFA 170 µg bid; or flunisolide HFA 340 µg bid. Dosing was continued for 13.5 days. Plasma samples were analyzed after the first dose on day 1 and again after 13.5 days of treatment. No significant differences in day 1 dose‐adjusted peak plasma concentrations (Cmax) were observed. Dose proportionality in Cmax and area under the concentration–time curves (AUC) was observed for the flunisolide HFA 170 and 340 µg bid groups on days 1 and 14. Day 1 mean dose‐adjusted AUC was significantly greater in the flunisolide CFC 1000 µg bid group than in either flunisolide HFA group, indicating greater systemic availability of flunisolide CFC. Oral clearance and volume of distribution were significantly higher for flunisolide CFC than for flunisolide HFA. This may be due to greater oropharyngeal deposition by the flunisolide CFC formulation. Another indicator of greater flunisolide CFC oropharyngeal deposition was observed in Cmax and AUC0–tlast values for 6β‐OH flunisolide, the first‐pass metabolite of flunisolide. The values of these pharmacokinetic parameters were significantly higher in the flunisolide CFC group than in the 340 µg bid flunisolide HFA group on days 1 and 14. However, this was not the case for cortisol values where flunisolide HFA accounted for less oropharyngeal deposition and more targeted delivery without adverse events. The study demonstrated that flunisolide HFA administered through a pMDI with built‐in spacer was safe and well tolerated in healthy volunteers. Copyright © 2001 John Wiley & Sons, Ltd.
Successful generalized parent training and failed schedule thinning of response blocking for automatically maintained object mouthing
Authors: Tarbox Jonathan , Wallace Michele D. , Tarbox Rachel S. F.
Published: September 2002

Mouthing of inedible objects maintained by automatic reinforcement can be particularly difficult to treat, given that the functional reinforcer is not socially mediated, and therefore it is difficult or impossible to withhold reinforcement. In the current investigation, response blocking was used to reduce automatically maintained object mouthing. Treatment effects were generalized to the natural environment. An attempt at schedule thinning was not successful; however, the participant's parents were trained to implement the treatment successfully in their home. Copyright © 2002 John Wiley & Sons, Ltd.
Calculability analysis in underdetermined metabolic networks illustrated by a model of the central metabolism in purple nonsulfur bacteria
Authors: Klamt Steffen , Schuster Stefan , Gilles Ernst Dieter
Published: September 2002

Metabolite balancing has turned out to be a powerful computational tool in metabolic engineering. However, the linear equation systems occurring in this analysis are often underdetermined. If it is difficult or impossible to find the missing constraints, it is nevertheless feasible in some cases to determine the values of a subset of the unknown rates. Here, a procedure for finding out which reaction rates can be uniquely calculated in underdetermined metabolic networks and computing these rates is given. The method is based on the null space to the stoichiometry matrix corresponding to the reactions with unknown rates. It is shown that this method is considerably easier to handle than an algorithm given previously (Van der Heijden et al., 1994a). Furthermore, a useful elementary representation of the null space is presented which is closely related with the elementary flux modes. This unique representation is central to a more general approach to observability/calculability analysis. In particular, it allows one to find, in an easy way, those sets of measurable rates that enable a calculation of a certain unknown rate. Besides, rates which are never calculable by metabolite balancing may be easily detected by this method.

The applicability of these methods is illustrated by a model of the central metabolism in purple nonsulfur bacteria. The photoheterotrophic growth of these representatives of anoxygenic photosynthetic bacteria is stoichiometrically analyzed. Interesting metabolic constraints caused by the necessary balancing of NAD(P)H can be detected in a highly underdetermined system. This is, to our knowledge, the first application of stoichiometric analysis to the metabolic network in this bacteria group using metabolite balancing techniques. A new software tool, the FluxAnalyzer, is introduced. It allows quantitative and structural analysis of metabolic networks in a graphical user interface. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 734–751, 2002; DOI 10.1002/bit.10153
Modeling of the biotransformation of crotonobetaine into L‐(−)‐carnitine by Escherichia coli strains
Authors: Canovas M. , Maiquez J. R. , Obón J. M. , Iborra J. L.
Published: September 2002

A simple unstructured model, which includes carbon source as the limiting and essential substrate and oxygen as an enhancing substrate for cell growth, has been implemented to depict cell population evolution of two Escherichia coli strains and the expression of their trimethylammonium metabolism in batch and continuous reactors. Although the model is applied to represent the trans‐crotonobetaine to L‐(−)‐carnitine biotransformation, it is also useful for understanding the complete metabolic flow of trimethylammonium compounds in E. coli. Cell growth and biotransformation were studied in both anaerobic and aerobic conditions. For this reason we derived equations to modify the specific growth rate, μ, and the cell yield on the carbon source (glycerol), Yxg, as oxygen increased the rate of growth. Inhibition functions representing an excess of the glycerol and oxygen were included to depict cell evolution during extreme conditions. As a result, the model fitted experimental data for various growth conditions, including different carbon source concentrations, initial oxygen levels, and the existence of a certain degree of cell death. Moreover, the production of enzymes involved within the E. coli trimethylammonium metabolism and related to trans‐crotonobetaine biotransformation was also modeled as a function of both the cell and oxygen concentrations within the system. The model describes all the activities of the different enzymes within the transformed and wild strains, able to produce L‐(−)‐carnitine from trans‐crotonobetaine under both anaerobic and aerobic conditions. Crotonobetaine reductase inhibition by either oxygen or the addition of fumarate as well as its non‐reversible catalytic action was taken into consideration. The proposed model was useful for describing the whole set of variables under both growing and resting conditions. Both E. coli strains within membrane high‐density reactors were well represented by the model as results matched the experimental data. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 764–775, 2002; DOI 10.1002/bit.10157
Miniaturized amperometric flow immunoassay system using a glass fiber membrane modified with anion
Authors: Lim Tae‐Kyu , Imai Satoko , Matsunaga Tadashi
Published: September 2002

This paper describes a miniaturized amperometric flow immunoassay system using a glass fiber membrane modified with anion. The glass fiber membrane was functionally modified with γ‐glycidoxypropyltrimethoxysilane and sodium thiosulfate and was used for separation of protein. Anti‐human chorionic gonadotrophin (HCG) immunoglobulin G (IgG) antibody conjugated with ferrocenemonocarboxylic acid (Fc), namely, Fc‐conjugated IgG (Fc–IgG), was used as a novel analytical reagent. HCG and Fc–IgG complexes were separated from free Fc–IgG based on differences in isoelectric point (pI) using the glass fiber membrane modified with a thiosulfonyl acid functional group. The assay yields a linear relationship between current and HCG concentration in the range of 0–2000 mIU/mL. This simple technique enables the assay of HCG within 2 min. The modified glass fiber membrane was regenerated by occasional elution with malonate buffer (pH 6.0) containing 0.5 M NaCl, to remove free Fc–IgG. Free Fc–IgG recovered in this manner could be reused up to eight times without significant decreases in sensitivity. This miniaturized amperometric flow immunoassay requires only minute quantities of serum and generates highly reproducible results. © 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 758–763, 2002; DOI 10.1002/bit.10158
Inhibition of sodium butyrate‐induced apoptosis in recombinant Chinese hamster ovary cells by constitutively expressing antisense RNA of caspase‐3
Authors: Kim No Soo , Lee Gyun Min
Published: September 2002

Sodium butyrate (NaBu) can enhance the expression of genes controlled by some of the mammalian promoters, but it can also inhibit cell growth and induce cellular apoptosis. Thus, the beneficial effect of using a higher concentration of NaBu on a foreign protein expression is compromised by its cytotoxic effect on cell growth. To overcome this cytotoxic effect of NaBu, the expression vector of antisense RNA of caspase‐3 was constructed and transfected to recombinant Chinese hamster ovary (rCHO) cells producing a humanized antibody. Using this antisense RNA strategy, rCHO cells (B3) producing a low level of caspase‐3 proenzyme were established. When batch cultures of both B3 cells and control cells transfected with antisense RNA‐deficient plasmid were performed in the absence of NaBu, both cells showed similar profiles of cell growth and antibody production. Compared with control cell culture, under the condition of 5 mM NaBu addition at the exponential growth phase, expression of antisense RNA of caspase‐3 significantly suppressed the NaBu‐induced apoptosis of B3 cells and extended culture longevity by >2 days if the culture was terminated at cell viability of 50%. However, compared with control cell culture, the final antibody concentration of B3 cell culture was not increased in the presence of NaBu, which may be due to the loss of cellular metabolic capability resulted from the depolarization of mitochondrial membrane. Taken together, this study suggests that, although expression of antisense RNA of caspase‐3 does not improve antibody productivity of rCHO cells, it can suppress NaBu‐induced apoptotic cell death of rCHO cells and thereby may reduce problems associated with cellular disintegration. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 217–228, 2002; DOI 10.1002/bit.10191
Decreasing the hyphal branching rate of Saccharopolyspora erythraea NRRL 2338 leads to increased resistance to breakage and increased antibiotic production
Authors: Wardell J. N. , Stocks S. M. , Thomas C. R. , Bushell M.E.
Published: September 2002

Mutation and selection for increased resistance to cell‐wall synthesis inhibitors led to alterations in the hyphal branching rate of Saccharopolyspora erythraea NRRL 2338. Mutants with decreased branching frequency exhibited increased hyphal strength (estimated by in vitro micromanipulation). As the hyphal strength was increased, this led to a greater proportion of hyphal particles in liquid culture with a hyphal fragment diameter of greater than 88 μm. This, in turn, coincided with proportionately increased antibiotic production. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 141–146, 2002; DOI 10.1002/bit.10210
Successional development of sulfate‐reducing bacterial populations and their activities in an activated sludge immobilized agar gel film
Authors: Okabe Satoshi , Santegoeds Cecilia M. , Watanabe Yoshimasa , Beer Dirk de
Published: September 2002

A combination of fluorescence in situ hybridization (FISH), microprofiles, and denaturing gradient gel electrophoresis (DGGE) analysis of PCR‐amplified 16S rDNA fragments followed by hybridization analysis with specific probes was applied to investigate successional development of sulfate‐reducing bacteria (SRB) community structure and in situ sulfide production activity within an activated sludge immobilized agar gel film. In this model biofilm system, since biases arising from biofilm heterogeneity can be ignored, the population dynamics of SRB in the agar gel is directly related to physiological capability and in situ activity of SRB. Microelectrode measurements showed that an anoxic zone was already developed at the beginning (0 day), a first sulfide production of 0.054 μmol H2S m−2 s−1 was detected during the first week, and the rate increased gradually to 0.221 μmol H2S m−2 s−1 in the fifth week. The most active sulfide production zone moved upward to the chemocline and intensified with time to form a narrow zone with high volumetric sulfide production rates. This result coincided with the shift of the spatial distributions of SRB populations determined by FISH. In situ hybridization with probe SRB385 for mainly general SRB of the delta Proteobacteria plus some gram‐positive bacteria and probe 660 for Desulfobulbus indicated that the most abundant populations of SRB were primarily restricted to near the oxic/anoxic interface (chemocline). A close observation of the development of the vertical distributions of SRB populations revealed that the cell numbers of Desulfobulbus tripled (from 0.5 × 108 to 1.5 × 108 cells cm−3) near the oxic/anoxic interface. Similar growth (from 1.0 ×108 to 4.5 × 108 cells cm−3) of Desulfovibrio‐like SRB that hybridized with probe SRB385 was observed. PCR‐DGGE followed by hybridization analysis revealed that one Desulfobulbus strain was detected from the beginning, and another strain appeared after 1 week, coinciding with the first detected sulfide production. In addition, three strains hybridizing with probe 687 (possibly Desulfovibrio) were also dominant SRB in the agar gel. © 2002 Wiley Periodicals, Inc. Biotechnol Bioeng 78: 119–130, 2002; DOI 10.1002/bit.10240
Process performance models in the optimization of multiproduct protein production plants
Authors: Pinto José M. , Montagna Jorge M. , Vecchietti Aldo R. , Iribarren Oscar A. , Asenjo Juan A.
Published: September 2002

In this work we propose a model that simultaneously optimizes the process variables and the structure of a multiproduct batch plant for the production of recombinant proteins. The complete model includes process performance models for the unit stages and a posynomial representation for the multiproduct batch plant. Although the constant time and size factor models are the most commonly used to model multiproduct batch processes, process performance models describe these time and size factors as functions of the process variables selected for optimization. These process performance models are expressed as algebraic equations obtained from the analytical integration of simplified mass balances and kinetic expressions that describe each unit operation. They are kept as simple as possible while retaining the influence of the process variables selected to optimize the plant. The resulting mixed‐integer nonlinear program simultaneously calculates the plant structure (parallel units in or out of phase, and allocation of intermediate storage tanks), the batch plant decision variables (equipment sizes, batch sizes, and operating times of semicontinuous items), and the process decision variables (e.g., final concentration at selected stages, volumetric ratio of phases in the liquid–liquid extraction). A noteworthy feature of the proposed approach is that the mathematical model for the plant is the same as that used in the constant factor model. The process performance models are handled as extra constraints. A plant consisting of eight stages operating in the single product campaign mode (one fermentation, two microfiltrations, two ultrafiltrations, one homogenization, one liquid–liquid extraction, and one chromatography) for producing four different recombinant proteins by the genetically engineered yeast Saccharomyces cerevisiae was modeled and optimized. Using this example, it is shown that the presence of additional degrees of freedom introduced by the process performance models, with respect to a fixed size and time factor model, represents an important development in improving plant design. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 451–465, 2001.
Evaluation of photobioreactor heat balance for predicting changes in culture medium temperature due to light irradiation
Authors: Morita Masahiko , Watanabe Yoshitomo , Saiki Hiroshi
Published: September 2002

Microalgal photosynthesis requires appropriate culture medium temperatures to achieve high photosynthetic performance and to maintain production of a high‐quality biomass product. Enclosed systems, such as our conical, helical tubular photobioreactor (HTP), can accomplish high photosynthetic efficiency and the small amount of culture medium used by these systems means that the culture medium temperature may be effectively controlled. On the other hand, because a high ratio of surface area to culture medium volume leads to rapid heating under the illumination condition and substantial heat loss at night, maintaining a suitable culture medium temperature is necessary to achieve efficient, commercially practical biomass production. In order to predict changes in the culture medium temperature caused by changes in solar irradiance and ambient temperature, it is necessary to understand the heat balance within the photobioreactor. We therefore investigated the heat balance in three major parts (photostage, degasser, and helical heat exchanger) of our conical HTP, analyzed the time‐dependent changes in medium temperature at various room temperatures and radiant energy inputs, and predicted changes in the culture medium temperature based on the characteristics of heat transfer among the three parts. Using this model, the predicted changes in culture medium temperature were very similar to the changes observed experimentally in the laboratory and under field conditions. This means that by calculating the time‐dependent changes in the culture medium temperature, based on measurements of solar energy input and ambient temperature, we should be able to estimate the energy required to maintain the culture medium temperature within a range where photosynthetic performance of microalgae is high. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 466–475, 2001.
Effects of nonionic surfactants on the UV/visible absorption of bacterial cells
Authors: Brown Derick G. , Jaffé Peter R.
Published: September 2002

Nonionic surfactants are used in a number of different microbiological applications, including solubilization of cell membranes, washing bacterial cultures prior to experimentation, and enhancing biodegradation of low‐solubility compounds. An important consideration in these applications is the potential for the surfactant to alter the cell membrane. One potential means to monitor the impact of surfactants on the bacterial cell membrane is through monitoring the absorbance spectrum of the bacterial suspension. This is due to the colloidal nature of bacteria, where the absorbance of a bacterial suspension is related to the size and refractive index of the bacterial cells. Through a systematic study it was shown that there can be a significant change in the bacterial absorbance spectrum due to the presence of nonionic surfactants, with the effect a function of surfactant structure and concentration, solution ionic strength and cation valence. The effects were most pronounced with Na+ as the cation, with surfactants having mid‐range hydrophile‐lipophile balance (HLB) values, and with surfactant concentrations above the CMC. The results indicate that measurement of the absorbance spectrum of bacterial cultures can provide a means to monitor the effects of nonionic surfactants on the bacterial cell membrane. In addition, depending on the specific application, appropriate selection of surfactant structure and media composition can be made to enhance or minimize the effects. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 476–482, 2001.
High‐level expression and stabilization of recombinant human chitinase produced in a continuous constitutive Pichia pastoris expression system
Authors: Goodrick J. C. , Xu M. , Finnegan R. , Schilling B. M. , Schiavi S. , Hoppe H. , Wan N. C.
Published: September 2002

A continuous fermentation process has been developed in Pichia pastoris (P. pastoris) with the glyceraldehyde‐3‐phosphate dehydrogenase (GAP) promoter in order to produce large quantities of recombinant human chitinase (rh‐chitinase) for preclinical studies as a potential high‐dose antifungal drug. Expression levels of about 200 to 400 mg/L have been demonstrated in fed‐batch fermentations using strains with either the traditional methanol‐inducible or the constitutive GAP promoter. Proteolytic degradation of the enzyme was typically seen in fed‐batch fermentations. Continuous production of the enzyme by P. pastoris with the GAP promoter was demonstrated in a 1.5‐L working volume fermentor using either glucose or glycerol as the carbon source. The fermentation could be extended for >1 month with a steady‐state protein concentration of approximately 300 mg/L. Cell densities were >400 g/L wet cell weight (WCW) (approximately 100 g/L dry cell weight [DCW]) at a dilution rate (D) of 0.83 day−1 or 1.2 volume exchanges per day (VVD). No proteolytic degradation of the enzyme was seen in the continuous fermentation mode. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 492–497, 2001.
Factors affecting α,‐1,2 glucooligosaccharide synthesis by Leuconostoc mesenteroides NRRL B‐1299 dextransucrase
Authors: Dols‐Lafargue Marguerite , Willemot René‐Marc , Monsan Pierre F. , Remaud‐Simeon Magali
Published: September 2002

The optimization of α‐1,2 glucooligosaccharide (GOS) synthesis from maltose and sucrose by Leuconostoc mesenteroides NRRL B‐1299 dextransucrase was achieved using experimental design and consecutive analysis of the key parameters. An increase of the pH of the reaction from 5.4 to 6.7 and of the temperature from 25 to 40°C significantly favored α‐1,2 GOS synthesis, thanks to a significant decrease of the side reactions, i.e., dextran and leucrose synthesis. These positive effects were not sufficient to compensate for the decrease of enzyme stability caused by the use of high pH and temperature. However, the critical parameters were the sucrose to maltose concentration ratio (S/M) and the total sugar concentration (TSC). α1,2 GOS synthesis was favored at high S/M ratios. But using these conditions also led to an increase of side reactions which could be modulated by choosing the appropriate TSC. Finally, with S/M = 4 and TSC = 45% w/v, dextran and leucrose productions were limited and the final α‐1,2 GOS yield reached 56.7%, the total GOS yield being 88%. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 498–504, 2001.
A priori analysis of metabolic flux identifiability from 13C‐labeling data
Authors: van Winden Wouter A. , Heijnen Joseph J. , Verheijen Peter J. T. , Grievink Johan
Published: September 2002

The 13C‐labeling technique was introduced in the field of metabolic engineering as a tool for determining fluxes that could not be found using the ‘classical’ method of flux balancing. An a priori flux identifiability analysis is required in order to determine whether a 13C‐labeling experiment allows the identification of all the fluxes. In this article, we propose a method for identifiability analysis that is based on the recently introduced ‘cumomer’ concept. The method improves upon previous identifiability methods in that it provides a way of systematically reducing the metabolic network on the basis of structural elements that constitute a network and to use the implicit function theorem to analytically determine whether the fluxes in the reduced network are theoretically identifiable for various types of real measurement data. Application of the method to a realistic flux identification problem shows both the potential of the method in yielding new, interesting conclusions regarding the identifiability and its practical limitations that are caused by the fact that symbolic calculations grow fast with the dimension of the studied system. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 74: 505–516, 2001.
Analysis of glycosaminoglycan‐derived disaccharides in biologic samples by capillary electrophoresis and protocol for sequencing glycosaminoglycans
Authors: Lamari F. N. , Militsopoulou M. , Mitropoulou T. N. , Hjerpe A. , Karamanos N. K.
Published: September 2002

Glycosaminoglycans are biologically significant carbohydrates which either as free chains (hyaluronan) or constituents of proteoglycans (chondroitin/dermatan sulfates, heparin, heparan sulfate and keratan sulfate) participate and regulate several cellular events and (patho)physiological processes. Capillary electrophoresis, due to its high resolving power and sensitivity, has been successfully used for the analysis of glycosaminoglycans. Determination of compositional characteristics, such as disaccharide sulfation pattern, is a useful prerequisite for elucidating the interactions of glycosaminoglycans with matrix effective molecules and, therefore, essential in understanding the biological functions of proteoglycans. The interest in the field of characterization of such biologically important carbohydrates is soaring and advances in this field will signal a new revolution in the area of glycomics equivalent to that of genomics and proteomics. This review focuses on the capillary electrophoresis methods used to determine the disaccharide pattern of glycosaminoglycans in various biologic samples as well as advances in the sequence analysis of glycosaminoglycans using both chromatographic and electrophoretic techniques. Copyright © 2002 John Wiley & Sons, Ltd.
A study of chiral recognition for NBD‐derivatives on a Pirkle‐type chiral stationary phase
Authors: Kato Masaru , Fukushima Takeshi , Shimba Nobuhisa , Shimada Ichio , Kawakami Yoshiyuki , Imai Kazuhiro
Published: September 2002

A chiral stationary phase (CSP 1) derived from an (S)‐N‐3,5‐dinitrobenzoyl‐1‐naphthylglycine showed excellent enantiomeric separation for amino acid derivatives with a fluorogenic reagent, 4‐fluoro‐7‐nitro‐2,1,3‐benzoxadiazole (NBD‐F), in high‐performance liquid chromatography (HPLC). We compared elution profiles (separation factor and elution order) of NBD‐amino acids and their analogs on HPLC, to determine the diastereomeric complex between the chiral moiety of CSP 1 and NBD‐amino acid, which is responsible for the chiral recognition. 1H‐NMR studies of a mixture of model compound of CSP 1 and NBD‐Ala suggest that the diastereomeric complex is composed of two hydrogen bonding sites at the amino proton and oxygen atom, and a π–π interaction by the benzofurazan structure (2,1,3‐benzoxadiazole) of NBD‐amino acid. Furthermore CSP 1 was able to separate esters, amides and α‐methyl amino acids derivatized with NBD‐F. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

ABD‐F

4‐aminosulfonyl‐7‐fluoro‐2,1,3‐benzoxadiazole

APCI

atmospheric chemical ionization

CSP

chiral stationary phase;

DCC

N,N′‐dicyclohexylcarbodiimide;

DMAP

4‐dimethylamino pyridine

DBD‐F

4‐(N,N′‐dimethylaminosulfonyl‐7‐fluoro‐2,1,3‐benzoxadiazole

DNM

[3,5‐dinitrophenylamido‐(s)‐1‐naphthylglycine]

HBD‐F

4‐fluoro‐2,1,3‐benzoxadiazole

NBD‐CL

4‐chloro‐7‐nitro‐2,1,3‐benzoxadiazole

NBD‐F

4‐fluoro‐7‐nitro‐2,1,3‐benzoxadiazole

TFA

trifluoroacetic acid
Determining the procedure for routine residue monitoring of sulfamethazine in edible animal tissues
Authors: Furusawa Naoto
Published: September 2002

A simplified method to determine/identify residual sulfamethazine (SMZ) in edible tissues from cattle, pigs, chickens and sheep by a high‐performance liquid chromatography (HPLC) with a photo‐diode array detector is presented. The sample preparation was performed by homogenizing with 30% (v/v) ethanol in water followed by an Ultrafree®‐MC/PL as a centrifugal ultra‐filtration unit. For determination/identification of SMZ, a reversed‐phase C4 column and a mobile phase of 15% (v/v) ethanol in water with a photo‐diode array detector was used. Average recoveries from spiked SMZ (0.1–1.0 mg kg−1) were ≥80% with coefficients of variation between 1.3 and 4.3%. The limits of quantitation were calculated to be 0.057–0.060 mg kg−1. The total time and solvent required for the analysis of one sample were <40 min and <2 mL of ethanol, respectively. Copyright © 2001 John Wiley & Sons, Ltd.
Determination of trimebutine maleate in rat plasma and tissues by using capillary zone electrophoresis
Authors: Li Famei , Yu Lining
Published: September 2002

A simple and rapid capillary zone electrophoresis method was developed for the determination of trimebutine maleate in rat plasma and tissues. Rat plasma and tissue homogenates were mixed with acetonitrile containing internal standard, ephedrine hydrochloride, and then centrifuged. The supernatant was dried under a stream of nitrogen, and the residue was reconstituted in methanol–water (1:1). The electrophoresis was performed in uncoated capillary with 30 mmol/L phosphate buffer of pH 6.0 as the separation electrolyte. The applied voltage was 10 kV and the UV detection was set at 214 nm. The peak height ratio vs concentration in plasma or homogenates was linear over the range of 5–500 ng/mL and the limit of quantitation was 5 ng/mL. The intra‐ and inter‐day precision was RSD < 14% and <15%. The accuracy was relative error (RE) within ± 14%. This method was applied to studying the pharmacokinetics and tissue distribution after a single dose of trimebutine maleate was administrated to the rats. The Tmax, AUC, Cmax and t1/2 were 30 min, 7.8 × 102 (ng/mL) min, 39 ng/mL and 1.7 × 102 min. The drug distribution was found in a decreasing order of liver, kidney, spleen, lung and heart. Copyright © 2001 John Wiley & Sons, Ltd.
A rapid, sensitive high performance liquid chromatographic method for the determination of meropenem in pharmaceutical dosage form, human serum and urine
Authors: Özkan Yalcin , Küçükgüzel İlkay , Özkan Sibel A. , Aboul‐Enein Hassan Y.
Published: September 2002

A new, simple, precise and rapid high performance liquid chromatographic method was developed for the determination of meropenem in human serum, urine and pharmaceutical dosage forms. Chromatography was carried out on an LC18 column using a mixture of 15 mM KH2PO4:acetonitrile:methanol (84:12:4; v/v/v), adjusted to pH 2.8 with H3PO4. The proposed method was conducted using a reversed‐phase technique, UV monitoring at 307.6 nm and cefepime as an internal standard. The retention times were 5.98 and 7.47 min for cefepime and meropenem, respectively. The detector response was linear over the concentration range of 50–10,000 ng/mL. The detection limit of the procedure was found to be 22 ng/mL. The detection limit for meropenem in human plasma was 108.4 ng/mL and the corresponding value in human urine was 179.3 ng/mL. No interference from endogenous substances in human serum, urine and pharmaceutical preparation was observed. The proposed method is sufficiently sensitive for determination of the concentrations of meropenem and may have clinical application for its monitoring in patients receiving the drug. Copyright © 2001 John Wiley & Sons, Ltd.
Quantification of D/L‐aspartic acids in Aplysia californica central nervous system by β‐cyclodextrin modified micellar electrokinetic chromatography
Authors: Zhao Shulin , Liu Yi‐Ming
Published: September 2002

In presence of an organic modifier (e.g. methanol), separation of amino acid enantiomers tagged with naphthalene‐2,3‐dicarboxaldehyde by β‐cyclodextrin modified micellar electrokinetic chromatography was dramatically improved. Coupled with laser‐induced fluorescence detection, the method was well suited for analysis of D/L‐amino acid enantiomers present in mass/volume‐limited biological samples such as cell clusters. The five major ganglia dissected from the central nervous system of Aplysia californica, a widely used neuronal model, were analyzed to determine D‐ and L‐aspartic acid enantiomers both free and bound in proteins/tissue matrix. The analyses revealed high levels of free D‐aspartic acid ranging from 0.13 to 0.82 µmol/g wet tissue (or 6.0–21.2% of the total free aspartic acid) in all of the five ganglia. However, no D‐aspartic acid was detected bound in protein/tissue matrix. The content of free D‐aspartic acid in the liver tissue was also found below the detection limit of the method, which was 1 × 10−8 M. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

CBI

1‐cyano‐2‐substituted benz[f]isoindole

CSF

cerebrospinal fluid

D‐Asp

D‐aspartic acid D‐Ser, D‐Serine

FITC

fluorescein isothiocyanate

KCN

potassium cyanide

OPA

ophthaldialdehyde

NDA

naphthalene‐2,3‐di‐carboxaldehyde

SDS

sodium dodecyl sulfate

TEA

triethylamine.
Simultaneous determination of clozapine, norclozapine and clozapine‐N‐oxide in human plasma by high‐performance liquid chromatography with ultraviolet detection
Authors: Liu Y. Y. , van Troostwijk L. J. A. E. Doude , Guchelaar H.‐J.
Published: September 2002

A reversed‐phase high‐performance liquid chromatographic (HPLC) method for the simultaneous determination of clozapine and its two major metabolites, norclozapine and clozapine‐N‐oxide in human plasma has been developed and validated. The isocratic HPLC assay uses a mobile phase consisting of an acetonitril‐buffered aqueous solution containing 146 µL of triethylamine and 200 µL of 85% phosphoric acid, adjusted to pH 3.3 with 10% potassiumhydroxide solution (400:600, v/v) at a flow‐rate of 0.8 ml/min and a Lichrospher 100 RP‐18 reversed‐phase column and UV detection at 215 nm. Doxepine was used as the internal standard. Mean recoveries for clozapine, norclozapine, clozapine‐N‐oxide and doxepine were 95%, 98%, 96% and 94%, respectively, whereas the respective mean repeatability coefficients of variation were 3.4%, 2.7%, 4.3% and 0.9%. Reproducibility coefficients of variation were 1.3%, 1.8%, 3.6% and 0.5%, respectively. The mean correlation coefficient for the linear calibration curve (n = 2) for clozapine and norclozapine at a concentration range of 100–1600 ng/mL was 0.9998 and 0.9997, respectively; for clozapine‐N‐oxide (20–200 ng/mL) it was found to be 0.9986. The lower limits of quantitation were 12.5 ng/mL, 10 ng/mL and 12.5 ng/mL for clozapine, norclozapine and clozapine‐N‐oxide, respectively. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

LLQ

lower limit of quantitation.
Moral justification forTarasoff‐type warnings and breach of confidentiality: a clinician's perspective
Authors: Gutheil Thomas G.
Published: September 2002

After brief review of the background and context of theTarasoffcase and its impact on clinicians, the author examines the “Tarasoffwarning,” proposed in the 1974Tarasoffopinion, from a moral position, with brief discussion of its clinical and risk management dimensions. Moral issues considered include confidentiality itself, agency, fiduciary duty, a shift in the victim paradigm, the emergency context, a novel risk, and a proposed approach. The dilemma presented by the originalTarasofffact situation is re‐examined. The author stresses the need for individualized responses to the risks posed by patients. Copyright © 2001 John Wiley & Sons, Ltd.
WWW courseware in applied science: Cases and lessons
Authors: Froese Thomas , Zhu David , Bhat Shankar
Published: September 2002

A project was conducted to investigate WWW courseware for a variety of applications to support a university engineering degree program. The overall results in terms of learning effectiveness, teaching efficiency, and distance education are discussed, as are lessons learned relating to development considerations and methodologies. An approach of assessing and comparing the various learning elements of both traditional and on‐line course delivery is presented. Three cases of development modules are then described, spanning general course support, on‐line instruction, and laboratory support. © 2001 John Wiley & Sons, Inc. Comput Appl Eng Educ 9: 63–77, 2001
Designing the microprocessor with Abel‐HDL
Authors: Guŝtin Veselko
Published: September 2002

In this article we introduce the use of the programmable logic circuit in students' work as an example of configuring the CPU (central processing unit). Since the concept of an in‐system configurable logic circuit is becoming increasingly popular, we now use it for the purpose of logic design. We suggest to students that they use programmable logic, as in constructing the CPU, with their own designed functions that are directly implemented in logic. Such an approach could greatly increase the understanding of the architectural concept of the CPU. © 2001 John Wiley & Sons, Inc. Comput Appl Eng Educ 9: 87–92, 2001
Magnetostatic analysis of a brushless DC motor using a two‐dimensional partial differential equation solver
Authors: Kostaridis A. , Soras C. , Makios V.
Published: September 2002

A finite element, magnetostatic analysis, of a brushless direct current motor containing non‐linear materials and permanent magnets is presented. The analysis is performed with PDEase™, a low cost, two‐dimensional partial differential equation solver. The descriptor file is remarkably short and easy to understand, enabling students to focus on the application and not on the finite element method. © 2001 John Wiley & Sons, Inc. Comput Appl Eng Educ 9: 93–100, 2001
Assessing volunteer motives: a comparison of an open‐ended probe and Likert rating scales
Authors: Allison Lora D. , Okun Morris A. , Dutridge Kathy S.
Published: September 2002

The purpose of the present study was to compare the motives of volunteers (career, esteem, protective, social, understanding, and value) as assessed by an open‐ended probe and the Volunteer Functions Inventory (VFI) which employs a Likert rating scale. One‐hundred‐and‐twenty‐nine individuals, who volunteered for an organization that focuses on episodic volunteering in the community, completed both measures of volunteer motives and reported their frequency of volunteering for the organization. The Spearman rank correlation between the rankings of the six volunteer motives in the two distributions was 0.71. The maximum variance shared between the same motive as assessed by the two methods was 0.14. Frequency of volunteering for the organization was predicted by the value (positive predictor) and social (negative predictor) VFI scale scores. A post hoc analysis of the data from the open‐ended probe revealed three additional motives for volunteering—enjoyment, religiosity, and team building. Copyright © 2002 John Wiley & Sons, Ltd.
Evidence for the involvement of polyunsaturated fatty acids in the regulation of long‐chain acyl CoA thioesterases and peroxisome proliferation in rat carcinosarcoma
Authors: Ramos Karina L. , Colquhoun Alison
Published: September 2002

The feeding of high‐fat diets rich in polyunsaturated fatty acids (PUFAs) caused a marked increase in the acyl CoA thioesterase activity of the Walker 256 tumour. Diets containing lower levels of PUFAs did not alter the activity of acyl CoA thioesterase and the exposure of LLC‐WRC256 tumour cells, in culture, to PUFAs (150 μM) also was ineffective in altering activity. The tumours from n‐3 PUFA‐rich and control diets were analysed by transmission electron microscopy in order to compare peroxisomal content. The presence of PUFAs led to an almost 10‐fold increase in the number of peroxisomes present in the tumour tissue. A common feature of the PUFA‐treated tumour was the presence of many cells containing highly condensed heterochromatin at the periphery of the nucleus, indicative of apoptosis. The sparsity of endoplasmic reticulum and the lack of detection of mitochondrial acyl CoA thioesterase, MTE‐I, led to the conclusion that the increase in tumour acyl CoA thioesterase activity may be due to an increase in the activity of the peroxisomal enzyme. Copyright © 2001 John Wiley & Sons, Ltd.
ACE in diabetes mellitus: Dr. Bilal Uuml;stundag replies
Authors: Üstundag Bilal
Published: September 2002

No abastract
Effects of polyamines on DNA synthesis using various subcellular DNA polymerases extracted from normal rat liver, tumour‐bearing rat liver, and tumour cells
Authors: Taguchi Takahiko , Kurata Sumiko , Ohashi Mochihiko
Published: September 2002

The effects of polyamines on DNA synthesis in vitro using various subcellular DNA polymerase fractions from normal and tumour‐bearing rat livers, and tumour cells were investigated. When nuclear and mitochondrial DNA polymerase fractions were used, DNA synthesis on activated DNA was increased 3.5–8‐fold by the addition of 20 mM putrescine or cadaverine. However, DNA synthesis was not stimulated by the addition of spermidine or spermine at any concentration tested. In contrast, DNA synthesis using the cytoplasmic DNA polymerase fraction was not stimulated at various concentrations of any of the four polyamines tested. The stimulatory effects of putrescine and cadaverine were absent when nuclear fractions from tumour‐bearing rat liver or from tumour cells were used. In addition, in vitro DNA synthesis was not stimulated by 20 mM putrescine or cadaverine when nuclear extracts from the livers of rats administered putrescine subcutaneously were used. The specific activities of DNA polymerases extracted from tumour cells and tumour‐bearing rat liver were already fully stimulated. These results suggest that DNA polymerases in tumour cells and tumour‐bearing liver cells are stimulated by trapped putrescine produced in tumour cells and are thus no longer activated by exogenous putrescine. Copyright © 2001 John Wiley & Sons, Ltd.
Control of apolipoprotein E secretion in the human hepatoma cell line KYN‐2
Authors: Brahimi Fouad , Bertrand Philippe , Starck Marjorie , Galteau Marie‐Madeleine , Siest Gérard
Published: September 2002

Even though it is known that apolipoprotein E (apoE) is deeply involved in major age‐related disorders such as atherosclerosis or Alzheimer's disease (AD), the control of cell‐specific apoE expression is still poorly understood. We compared the apoE secretion as previously described in astrocytic cell17 to hepatic cell apoE secretion. We used the human hepatoma cell line KYN‐2 to better delineate the characteristics of apoE secretion and to validate it with respect to the classical human hepatoma cell line HepG2. Interleukin‐1β (IL‐1β) and interferon‐γ (IFN‐γ) significantly inhibited, while IL‐2, IL‐6 and tumour necrosis factor‐α (TNF‐α) were inactive on apoE secretion by KYN‐2 as well as HepG2 cells. Cholesterol and 25‐OH cholesterol had no effect, while forskolin exerted a significant inhibitory effect, on apoE secretion in KYN‐2 cells. Our results suggest that the KYN‐2 cell line represents an appropriate cell model, and in any case an alternative model to the HepG2 cell line, to study the control of apoE secretion. The response of KYN‐2 cells to both cytokines and cholesterol differs from that found in astrocytoma cells, suggesting that blood variations of apoE concentrations in AD may not reflect the dysregulations taking place in the brain. Copyright © 2001 John Wiley & Sons, Ltd.