bluuebunny/crossref_metadata_2025 huggingface dataset:
Stimulation of DNA repair as an evolutionary drive for bacterial luminescence
Authors: Czyż Agata , Plata Konrad , Wȩgrzyn Grzegorz
Published: April 2003

It was demonstrated recently that luminescence of a free‐living marine bacterium, Vibrio harveyi, stimulates DNA repair, most probably by activation of the photoreactivation process. Here, we ask whether the stimulation of DNA repair could be an evolutionary drive that ensured maintenance and development of early bacterial luminescent systems. To test this hypothesis, we cultivated V. harveyi lux+ bacteria and luxA mutants in mixed cultures. Initial cultures were mixed to obtain a culture consisting of roughly 50% lux+ cells and 50% luxA mutants. Then bacteria were cultivated for several days and ratio of luminescent to dark bacteria was measured. Under these conditions, luxA mutants became highly predominant within a few days of cultivation. This indicates that, without a selective pressure, the luminescence is a disadvantage for bacteria, perhaps due to consumption of significant portion of cell energy. However, when the same experiments were repeated but cultures were irradiated with low UV doses, luminescent bacteria started to predominate shortly after the irradiation. Therefore, we conclude that stimulation of photoreactivation may be an evolutionary drive for bacterial bioluminescence. Copyright © 2003 John Wiley & Sons, Ltd.
RGD‐grafted poly‐l‐lysine‐graft‐(polyethylene glycol) copolymers block non‐specific protein adsorption while promoting cell adhesion
Authors: VandeVondele Stephanie , Vörös Janos , Hubbell Jeffrey A.
Published: April 2003

A novel class of surface‐active copolymers is described, designed to protect surfaces from nonspecific protein adsorption while still inducing specific cell attachment and spreading. A graft copolymer was synthesized, containing poly‐(L‐lysine) (PLL) as the backbone and substrate binding and poly(ethylene glycol) (PEG) as protein adsorption‐resistant pendant side chains. A fraction of the grafted PEG was pendantly functionalized by covalent conjugation to the peptide motif RGD to induce cell binding. The graft copolymer spontaneously adsorbs from dilute aqueous solution onto negatively charged surfaces. The performance of RGD‐modified PLL‐g‐PEG copolymers was analyzed in protein adsorption and cell culture assays. These coatings efficiently blocked the adsorption of serum proteins to Nb2O5 and tissue culture polystyrene while specifically supporting attachment and spreading of human dermal fibroblasts. This surface functionalization technology is expected to be valuable in both the biomaterial and biosensor fields, because different signals can easily be combined, and sterilization and application are straightforward and cost‐effective. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 784–790, 2003.
Salt hydrates for in situ water activity control have acid–base effects on enzymes in nonaqueous media
Authors: Fontes Nuno , Harper Neil , Halling Peter J. , Barreiros Susana
Published: April 2003

Salt hydrates very frequently are utilized as in situ water activity buffers in reaction mixtures of enzymes in nonaqueous media. In addition to buffering water activity, there is evidence that salt hydrates also often affect initial rates in other ways. This has been generally overlooked or thought to be related to water transfer effects. Here we show that salt hydrates can have important acid–base effects on enzymes in nonaqueous media. We performed transesterification reactions in n‐hexane and in supercritical ethane catalyzed by cross‐linked crystals of subtilisin, differing in the method used to set aW, and confirmed that the presence of salt hydrate pairs significantly affected the catalytic performance of the enzyme. However, in the presence of a solid‐state acid–base buffer, salt hydrates had no effect on enzymatic activity. Direct evidence for the acid–base effects of salt hydrates was obtained by testing their effect on the protonation state of an organo‐soluble H+/Na+ indicator. The four salt hydrate pairs tested affected the indicator to very different extents. By promoting the exchange of H+ for Na+, salt hydrates will tend to affect the ionization state of acidic residues in the protein and, hence, enzymatic activity. In fact, salt hydrates were able to affect the pH memory of subtilisin lyophilized from different aqueous pHs, bringing about up to 20‐fold enhancements and up to 5‐fold decreases in catalytic activity. The possibility of such acid–base effects need to be considered in all experiments using salt hydrates to control water activity. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 802–808, 2003.
Novel escherichia coli strain allows efficient recombinant protein production using lactose as inducer
Authors: Menzella Hugo G. , Ceccarelli Eduardo A. , Gramajo Hugo C.
Published: April 2003

An important characteristic of promoters used in recombinant protein production in Escherichi coli is their inducibility in a simple and cost‐effective manner. The IPTG inducible promoters lac, tac, and trc are powerful and widely used for basic research. However, the use of IPTG in large‐scale production is undesirable due to its high cost and toxicity. The promoters mentioned above can also be induced by the addition of lactose, which has the double role of inducer and carbon and energy source. Nevertheless, the use of this sugar in industrial processes has several drawbacks, which result in low volumetric yields and difficulties in process control. We have genetically engineered a BL21 strain to allow the efficient use of lactose as inducer in fed‐batch cultures. Two modifications were introduced, the exchange of the wild‐type lac operator by a constitutive one (lacOc) and the replacement of the gal alleles to recover the Gal+ phenotype. The constitutive expression of the lac operon overcame the negative effects that the Lac nongenetic heterogeneity of wild‐type E. coli introduces when lactose is used as inducer. The gal+ genotype allowed the complete use of the lactose as carbon and energy source. The relevance of these two modifications in the efficient utilization of lactose as inducer was demonstrated in fed‐batch cultures of the novel recombinant strain MP101 harboring expression vectors containing the calf prochymosin gene or the pccB gene, which encodes for the carboxyltransferase component of a propionyl‐CoA carboxylase complex from Streptomyces coelicolor. Similar levels of recombinant protein production (up to 16 g/L) were obtained by using either lactose or IPTG as inducers, which confirmed the success of the genetics modifications introduced. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 809–817, 2003.
Control of xylose consumption by xylose transport in recombinant Saccharomyces cerevisiae
Authors: Gárdonyi Márk , Jeppsson Marie , Lidén Gunnar , Gorwa‐Grauslund Marie F. , Hahn‐Hägerdal Bärbel
Published: April 2003

Saccharomyces cerevisiae TMB3001 has previously been engineered to utilize xylose by integrating the genes coding for xylose reductase (XR) and xylitol dehydrogenase (XDH) and overexpressing the native xylulokinase (XK) gene. The resulting strain is able to metabolize xylose, but its xylose utilization rate is low compared to that of natural xylose utilizing yeasts, like Pichia stipitis or Candida shehatae. One difference between S. cerevisiae and the latter species is that these possess specific xylose transporters, while S. cerevisiae takes up xylose via the high‐affinity hexose transporters. For this reason, in part, it has been suggested that xylose transport in S. cerevisiae may limit the xylose utilization.

We investigated the control exercised by the transport over the specific xylose utilization rate in two recombinant S. cerevisiae strains, one with low XR activity, TMB3001, and one with high XR activity, TMB3260. The strains were grown in aerobic sugar‐limited chemostat and the specific xylose uptake rate was modulated by changing the xylose concentration in the feed, which allowed determination of the flux response coefficients. Separate measurements of xylose transport kinetics allowed determination of the elasticity coefficients of transport with respect to extracellular xylose concentration. The flux control coefficient, C, for the xylose transport was calculated from the response and elasticity coefficients. The value of C for both strains was found to be < 0.1 at extracellular xylose concentrations > 7.5 g L−1. However, for strain TMB3260 the flux control coefficient was higher than 0.5 at xylose concentrations < 0.6 g L−1, while C stayed below 0.2 for strain TMB3001 irrespective of xylose concentration. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 818–824, 2003.
New approach to regioselective synthesis: Using proteins in vitro as guidance—regioselective reduction of steroids with guidance from bovine serum albumin
Authors: Liu Xiao‐Chuan , Kayser Lauren
Published: April 2003

A novel approach for regioselective synthesis is described. The approach uses the unique binding properties of protein as a guide to achieve regioselectivity. Specifically, steroids, e.g., 4‐androstene‐3,17‐dione, were reduced selectively at carbon 17 using bovine serum albumin (BSA) as a regio auxlliary. The approach has resulted in a high yield (ca. 91%) in an environmental friendly aqueous medium. Both 1H NMR and 13C NMR data show that the BSA‐assisted reduction of the steroid render the reaction regioselective compared to the control reaction. Various control reactions were performed to verify that the unique binding of BSA to steroids was the origin of regioselectivity. After one cycle of the reduction reaction, BSA was reconditioned such that it could be reused five or more times. This novel approach could be used to develop practical and “green” methods for regioselective synthesis. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 858–863, 2003.
Production of mannitol and lactic acid by fermentation with Lactobacillus intermedius NRRL B‐3693
Authors: Saha Badal C. , Nakamura Lawrence K.
Published: April 2003

Lactobacillus intermedius B‐3693 was selected as a good producer of mannitol from fructose after screening 72 bacterial strains. The bacterium produced mannitol, lactic acid, and acetic acid from fructose in pH‐controlled batch fermentation. Typical yields of mannitol, lactic acid, and acetic acid from 250 g/L fructose were 0.70, 0.16, and 0.12 g, respectively per g of fructose. The fermentation time was greatly dependent on fructose concentration but the product yields were not dependent on fructose level. Fed‐batch fermentation decreased the time of maximum mannitol production from fructose (300 g/L) from 136 to 92 h. One‐third of fructose could be replaced with glucose, maltose, galactose, mannose, raffinose, or starch with glucoamylase (simultaneous saccharification and fermentation), and two‐thirds of fructose could be replaced with sucrose. L. intermedius B‐3693 did not co‐utilize lactose, cellobiose, glycerol, or xylose with fructose. It produced lactic acid and ethanol but no acetic acid from glucose. The bacterium produced 21.3 ± 0.6 g lactic acid, 10.5 ± 0.3 g acetic acid, and 4.7 ± 0.0 g ethanol per L of fermentation broth from dilute acid (15% solids, 0.5% H2SO4, 121°C, 1 h) pretreated enzyme (cellulase, β‐glucosidase) saccharified corn fiber hydrolyzate. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 864–871, 2003.
In vitro model of “wound healing” analyzed by laser scanning cytometry: Accelerated healing of epithelial cell monolayers in the presence of hyaluronate
Authors: Haider Asifa S. , Grabarek Jerzy , Eng Ben , Pedraza Paulina , Ferreri Nicholas R. , Balazs Endre A. , Darzynkiewicz Zbigniew
Published: April 2003

Background

In vitro models of “wound healing” rely on analysis of confluent cell cultures that are mechanically wounded, e.g., by scratching the cell monolayer. Damage and removal of cells during wounding provides mitogenic signals to the adjacent cells and induces their migration to close the wound. The progress of healing is generally estimated by microscopy or time‐lapse cinematography by assessing cell proliferation and/or migration that leads to the wound closure.

Methods

The aim of the present study was to adapt laser scanning cytometry (LSC) to measure cellular changes related to damage and recovery of a monolayer of primary epithelial cells from rat kidneys growing with and without hyaluronate (∼6 × 106 average molecular weight). Because x–y coordinates of the cell position on the slide were recorded by LSC, the apoptotic and proliferative changes in individual cells induced by wounding and wound closure could be correlated, by multiparameter analysis, with the cell location with respect to the wound.

Results

The initial change, observed as soon as 4 h after scratching and seen among the cells at the wound edge, was the appearance of apoptotic cells, characterized by cell shrinkage, typically condensed chromatin, and activation of caspases, the latter detected by binding of fluorochrome‐labeled inhibitor of caspases. Their frequency was reduced to up to sixfold in the presence of hyaluronate. Cell proliferation, measured by frequency of cells incorporating bromodeoxyuridine, also reflected by percentage of cells in S, G2, and mitosis, was higher in proximity of the wound but was not significantly affected by hyaluronate. However, the monolayer gap closure was accelerated in the presence of hyaluronate.

Conclusions

By offering the means to measure apoptosis and proliferation in relation to the cell position (distance) with respect to the wound in cell monolayer and to relocate them for visual inspection, LSC is uniquely suited to quantitatively analyze in vitro the process of wound healing. Hyaluronate, the ubiquitous component of intercellular matrix, preparations of which are being used in the clinic to suppress inflammatory reactions in tissues and promote healing, accelerated the healing process by protecting cells from apoptosis and stimulating cell migration to close the gap in the cell monolayer. Cytometry Part A 53A:1–8, 2003. © 2003 Wiley‐Liss, Inc.
Quantitative fluorescence of 5‐FU–treated fetal rat limbs using confocal laser scanning microscopy and Lysotracker Red
Authors: Price Owen T. , Lau Christopher , Zucker Robert M.
Published: April 2003

Background

LysoTracker Red (LT) is a paraformaldehyde fixable probe that concentrates into acidic compartments of cells and tissues. After cell death, a high level of lysosomal activity (acidic enzyme) is expressed in tissues resulting from phagocytosis of apoptotic bodies by neighboring cells. LT was shown previously to be an indicator of cell death in a manner similar to other standard assays (Annexin, terminal dUTP nick end labeling, Nile blue sulfate, neutral red, and acridine orange).

Methods

LT fluorescence in fetal rat hindlimbs at gestational day 14 was measured 8 h after administration of the teratogen, 5‐fluorouracil (5‐FU), with the use of confocal laser scanning microscopy (CLSM). Four dose levels of 5‐FU (0, 20, 30, and 40 mg/kg) were studied. The preparation technique involved staining with LT, paraformaldehyde fixation, methanol dehydration, and clearance with benzyl alcohol and benzyl benzoate. After this treatment, the limb was nearly transparent and ready for CLSM analysis.

Results

LT staining was observed in specific regions undergoing apoptosis in normal (control) hindlimbs. After 5‐FU treatment, highly fluorescent regions appeared in the progress zone (PZ) of the limb. A dose‐dependent response to 5‐FU treatment was observed. Compared with controls, hindlimbs treated with 20, 30, and 40 mg/kg of 5‐FU exhibited more fluorescence within the highly proliferative PZ. These results showed a dose–response relation between 5‐FU exposure and LT uptake.

Conclusions

We found that three‐dimensional volumetric regions indicating a high level of fluorescence in the embryonic limb bud can be quantified with three different computer analysis programs. The combination of a sample preparation procedure that clears tissue, a CLSM technique that addresses the equipment variables, and an application of statistical population analysis procedures enabled the visualization and quantification of fluorescence in entire fetal rat hindlimbs that were approximately 500 μm in thickness. Cytometry Part A 53A:9–21, 2003. Published 2003 Wiley‐Liss, Inc.
Optimal preparation of rhesus macaque blood for cytokine flow cytometric analysis
Authors: Nomura Laurel E. , deHaro Eileen D. , Martin Louis N. , Maecker Holden T.
Published: April 2003

Background

The rhesus macaque is a common substitute for human subjects in many disease models, including simian immunodeficiency virus, the non‐human primate equivalent of the human immunodeficiency virus. Monoclonal antibodies and fluorochromes optimized for use in macaques were included in samples examined for immune responses with the use of intracellular cytokine flow cytometry (CFC).

Methods

Sample preparation was optimized based on the following comparisons: activation of peripheral blood mononuclear cells (PBMCs) versus whole blood; separation of PBMCs using BD Vacutainer cell preparation tubes versus Ficoll; and activation of samples on the day they were collected versus holding samples overnight.

Results

When activated with the simian immunodeficiency virus type mac239 and Gag peptide mix or with the superantigen Staphylococcal enterotoxin B, separated PBMCs produced greater CD4 and CD8 fluorescence intensities and a larger percentage of CD69+ cytokine‐positive cells than did whole blood samples. PBMCs separated by cell preparation tubes produced absolute T‐lymphocyte counts equivalent to that with Ficoll separation, and CFC results with both methods were similar. When subjected to overnight shipping conditions, whole blood and PBMCs sometimes showed a reduction in mean fluorescence intensity and percentage of CD69+ cytokine‐positive T lymphocytes.

Conclusions

Due to this reduction in responses, it is preferable to activate samples on the day of blood collection. Samples can be surface stained and frozen in BD FACS Lysing Solution, to be thawed at a later date; this preserves their ability to display a cytokine response. Thus optimal CFC results are achieved by separating macaque PBMCs from whole blood, activating samples on day of collection, and, if necessary, freezing samples after surface staining for future analysis. Cytometry Part A 53A:28–38, 2003. © 2003 Wiley‐Liss, Inc.
Genetic linkage maps of the West African clawed frog Xenopus tropicalis
Authors: Kochan Kelli J. , Wright David A. , Schroeder Lisa J. , Shen Jianjun , Morizot Donald C.
Published: April 2003

The original article to which this Erratum refers was published in Developmental Dynamics 226:99–102 Developmental Dynamics(2003) 226(1) 99–102
Malleal processus brevis is dispensable for normal hearing in mice
Authors: Zhang Zunyi , Zhang Xiaoyun , Avniel Wilma A. , Song Yiqiang , Jones Sherri M. , Jones Timothy A. , Fermin Cesar , Chen Yiping
Published: April 2003

The mammalian middle ear cavity contains a chain of three ossicles (the malleus, incus, and stapes), which develop from the mesenchyme of the first two branchial arches. Mice deficient in the Msx1 homeobox gene exhibit craniofacial abnormalities, including the absence of the malleal processus brevis that is normally attached to the upper part of the tympanic membrane. Here, we show that the expression of Msx1 and Msx2 overlaps in the malleal primordium during early embryonic development. A functional redundancy of Msx1 and Msx2 in the development of the middle ear is suggested by the stronger hypomorphism in the malleus of Msx1‐/‐/Msx2‐/‐ embryos, including the absence of the malleal manubrium and the malleal processus brevis. The expression of Bmp4, a known downstream target of Msx1 in several developing craniofacial organs, was down‐regulated in the malleal primordium, particularly in the region of the developing malleal manubrium, of Msx1 and Msx1‐/‐/Msx2‐/‐ embryos. Msx genes, thus, appear to act in a cell autonomous manner, possibly by regulating Bmp4 expression, in the formation of the malleus. Transgenic rescue of the cleft palate of Msx1‐/‐ mice overcame the neonatal lethality and allowed Msx1‐/‐ mice to grow into adulthood but retain the phenotype of the absence of the malleal processus brevis. The availability of this animal model for the first time allowed us to measure auditory evoked potentials to assess the functional significance of the malleal processus brevis. The results demonstrated unimpaired auditory function in Msx1‐/‐ mice. In addition, mutant mice appeared normal in balance behavior and in the vestibular evoked potential screening test. These results indicate that the malleal processus brevis is not necessary for sound transmission and seems dispensable for normal hearing and balance in mammals. Developmental Dynamics 227:69–77, 2003 © 2003 Wiley‐Liss, Inc.
Differential expression of the two Drosophila fos/kayak transcripts during oogenesis and embryogenesis
Authors: Souid Sami , Yanicostas Constantin
Published: April 2003

The Dfos/kayak gene encodes a bZIP protein, DFos, required in a large variety of differentiation and morphogenetic processes throughout Drosophila development. The recent availability of an expressed sequence tag (EST) sequence led us to identify a novel kay mRNA encoding a deduced DFos isoform showing a specific NH2‐terminal region. To gain further insight into the function and the regulation of this gene, we have investigated the expression pattern of the two kay mRNA isoforms, kay‐RA and kay‐RB, during oogenesis and embryogenesis by whole‐mount in situ hybridization. Results show that, although the two kay RNA isoforms display fully distinct patterns of transcription during oogenesis, they show partially overlapping expression profiles in embryos. These data reveal a previously unsuspected level of complexity in the regulation of the expression of the kay gene. In addition, they suggest a possible requirement for this gene in the invagination processes during early gastrula stages. Developmental Dynamics, 227:150–154, 2003. © 2003 Wiley‐Liss, Inc.
Genomic organization and promoter and transcription regulatory regions for the expression in the anterior brain (sensory vesicle) of Hroth, the otx homologue of the ascidian, Halocynthia roretzi
Authors: Oda‐Ishii Izumi , Saiga Hidetoshi
Published: April 2003

Otx (otd in Drosophila) is a well‐conserved homeobox gene throughout animal phylogeny and commonly expressed in the anterior part of the embryo. In embryos of the ascidian Halocynthia roretzi, Hroth, the otx homologue in this species, is expressed in the endoderm and the sensory vesicle, the anterior part of the larval ascidian central nervous system (CNS), which has been thought to be homologous to vertebrate forebrain and midbrain. The developmental expression pattern of Hroth is very similar to that of vertebrate counterparts, which leads to a possibility that a similar mechanism may exist in the patterning of the CNS between ascidians and vertebrates. To better understand the mechanism, we decided to undertake analysis of the transcriptional regulatory regions of Hroth. We isolated and determined the nucleotide sequence of the 11.4‐kbp region upstream of the translation start site of Hroth. We found that Hroth transcripts are modified likely with spliced leader RNA; therefore, we could not determine the transcription start site. However, first, we identified three introns that are unknown with vertebrate otx genes. Second, we found two regions that are capable of functioning as a promoter through deletion analysis, one of which appeared to be an endogenous promoter of Hroth. We analyzed the 5′ upstream region 5402‐1473bp, the region between 1473 and 5402 base pairs upstream from the translation start site of Hroth, including the putative endogenous promoter. This region was capable of driving Hroth expression in the sensory vesicle lineage cells as well as some other lineages at the early tail bud stage. Deletion analysis of this region suggested that three regions, 1659‐1650bp, 1628‐1613bp, and 1542‐1473bp are responsible for regulating Hroth expression in the sensory vesicle cells at the tail bud stage. Among these regions, no apparent sequence conservation was observed. The present study has revealed a complex organization of transcription regulatory regions for the ascidian otx. Developmental Dynamics 227:104–113, 2003. © 2003 Wiley‐Liss, Inc.
Fetterman‐House: A Process Use Distinction and a Theory
Authors: Fetterman David
Published: April 2003

Theories of action and use shed light on empowerment evaluation as a specific approach and may be enabling tools in our discourse about the role of theory and practice in the field as a whole.
Evaluation Theory and Practice: Insights and New Directions
Authors: Alkin Marvin C.
Published: April 2003

This chapter offers a synthesis of the critical commentaries of each of the previous chapters, along with additional commentary on evaluation theory and practice.
Understanding Evaluation Theory and its Role in Guiding Practice: Formal, Folk, and Otherwise
Authors: Christie Christina A.
Published: April 2003

The author makes a final comment on the empirical study of evaluation theory and practice.
Pricing continuously sampled Asian options with perturbation method
Authors: Zhang Jin E.
Published: April 2003

This article explores the price of continuously sampled Asian options. For geometric Asian options, we
present pricing formulas for both backward‐starting and forward‐starting cases. For arithmetic
Asian options, we demonstrate that the governing partial differential equation (PDE) cannot be
transformed into a heat equation with constant coefficients; therefore, these options do not have a
closed‐form solution of the Black–Scholes type, that is, the solution is not given in terms of the
cumulative normal distribution function. We then solve the PDE with a perturbation method and obtain an
analytical solution in a series form. Numerical results show that as compared with Zhang's (2001) highly accurate numerical results, the series converges very quickly and gives a
good approximate value that is more accurate than any other approximate method in the literature, at least for
the options tested in this article. Graphical results determine that the solution converges globally very
quickly especially near the origin, which is the area in which most of the traded Asian options fall. ©
2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:535–560, 2003
The effect of liquidity constraints on futures hedging
Authors: Lien Donald
Published: April 2003

This article assumes that because of liquidity constraints, a hedge program will be terminated if the
cumulative loss from a futures position exceeds a certain threshold. The constraint leads to a smaller futures
position. If the hedger has a quadratic utility function, then the optimal futures position is constant regardless
of the parameter values and increases as the spot position or the conventional hedge ratio increases. When the
capital allocation is small, the hedger tends to ignore this restriction and chooses a larger position.
Consequently, the optimal position may decrease as the capital allocation increases. For a moderate capital
allocation, the optimal position increases with an increasing capital allocation. Similar properties are
established for exponential utility functions. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:603–613,
2003
Sarbanes–Oxley: How will it affect auditing?
Authors: Munter Paul
Published: April 2003

In the wake of recent corporate scandals, Congress hurriedly passed a massive, complex reform bill—the
Sarbanes–Oxley Act. How will it affect auditing? The author provides a road map—and some
important answers. © 2003 Wiley Periodicals, Inc.
Operational reviews and auditing ERP
Authors: Goldberg Stephen R. , Godwin Joseph H.
Published: April 2003

Reider, Rob. 2002. Operational Review: Maximum Results at Efficient Costs, 3rd edition
(New York: John Wiley & Sons).

Musaji, Yusufali F. 2002. Integrated Auditing of ERP Systems (New York: John Wiley &
Sons).
Regulation of the mesangial cell myofibroblast phenotype by actin polymerization
Authors: Patel Keyur , Harding Pamela , Haney Lisa B. , Glass William F.
Published: April 2003

Mesangial cells in diverse glomerular diseases become myofibroblast‐like, characterized by activation of smooth muscle α‐actin (α‐SMA) expression. In cultured mesangial cells, serum‐deprivation markedly increases α‐SMA expression, cell size, and stress fiber formation. Since stress fibers are assembled from actin monomers, we investigated the hypothesis that alterations in stress fiber formation regulate α‐SMA expression and hypertrophy. Human mesangial cells were treated with agents that disrupt or stabilize actin stress fibers. Depolymerization of actin stress fibers in serum‐deprived cells with actin‐depolymerizing agents, cytochalasin B (CytB) and latrunculin B (LatB), or with inhibitors of Rho‐kinase, Y‐27632 and HA‐1077 decreased α‐SMA mRNA as judged by Northern blot analysis. Western blot analysis showed that CytB also reduced α‐SMA protein levels. In serum‐fed cells, agents that stabilized actin stress fibers, jasplakinolide (Jas) and phalloidin, increased α‐SMA mRNA and protein. Treatment of human or rat mesangial cells with CytB, LatB, or Y‐27632 decreased α‐SMA promoter activity. In contrast, Jas increased promoter activity 5.6‐fold in rat mesangial cells. The presence of an RNA polymerase inhibitor blocked degradation of α‐SMA mRNA in cells treated with CytB suggesting that destabilization of this message is dependent on a newly transcribed or rapidly degraded factor. Inhibition of actin polymerization by CytB, LatB, Y‐27623, and HA‐1077 inhibited incorporation of 3[H]‐leucine into newly synthesized protein. Additionally, CytB and LatB decreased cell volume as determined by flow cytometry. Collectively, these results indicate that the state of polymerization of the actin cytoskeleton regulates α‐SMA expression, hypertrophy, and myofibroblast differentiation in mesangial cells. © 2003 Wiley‐Liss, Inc.
Tensile stress induces α‐adaptin C production in mouse calvariae in an organ culture: Possible involvement of endocytosis in mechanical stress‐stimulated osteoblast differentiation
Authors: Shimomura Junko , Ishibashi Osamu , Ikegame Mika , Yoshizawa Tatsuya , Ejiri Sadakazu , Noda Tadashi , Kawashima Hiroyuki
Published: April 2003

We previously demonstrated that tensile stress (TS)‐induced osteoblast differentiation eventually led to osteogenesis in an organ culture of mouse calvarial sutures. In the present study, we employed RNA‐fingerprinting using an arbitrarily primed polymerase chain reaction (RAP‐PCR) to identify α‐adaptin C, a component of the endocytosis machinery AP2, as a TS‐inducible gene. Protein production, as well as the gene expression of α‐adaptin C, was induced by TS as early as 3 h following the initiation of loading. In situ hybridization and immunohistochemical analysis revealed that the induction of α‐adaptin C mostly occurred in fibroblastic cells in the sutures, suggesting that it precedes TS‐induced osteoblast differentiation. Consistent with this result, TS significantly increased the number of coated pits (CPs) and coated vesicles (CVs) in the undifferentiated fibroblastic cells but not in the osteoblastic cells around calvarial bones. Further, TS‐induced osteoblast differentiation was suppressed when endocytosis was inhibited by potassium depletion. These results, taken together, suggest that TS accelerates osteoblast differentiation and osteogenesis, possibly through the induction of the α‐adaptin C expression and consequent activation of receptor‐mediated endocytosis. © 2003 Wiley‐Liss, Inc.
Differential physiological expression of the invertebrate 2Na+/1H+ antiporter in single epithelial cell type suspensions of lobster hepatopancreas
Authors: Mandal Prabir K. , Mandal Anita , Ahearn Gregory A.
Published: April 2003

Lobster (Homarus americanus) hepatopancreas is a complex, heterogeneous tissue composed of four epithelial cell types that individually contribute to the overall functional properties of digestion, absorption, secretion, and detoxification. Previous studies, using purified hepatopancreatic brush border membrane vesicles, have described the properties of an electrogenic, 2Na+/1H+ antiporter in this tissue that regulates the absorption and secretion of these cations. These studies were not able to localize this cation exchange phenomenon to specific epithelial cell types. In the present study, sodium/proton exchange by purified, single cell, suspensions of lobster (Homarus americanus) hepatopancreatic epithelium was investigated using a centrifugal elutriation method to cleanly separate the four individual cell types for subsequent physiological characterization. Results indicate that all four hepatopancreatic epithelial cell types possessed the 2Na+/1H+ antiporter as a result of its unique sigmoidal influx properties. Hill Coefficients, measures of transport sigmodicity obtained from kinetic analyses of 22Na+ influx by single cell type suspensions, varied from 1.56±0.30 (R‐cell suspensions) to 2.79±0.41 (F‐cell suspensions), suggesting that different numbers of sodium ions may be accommodated by each cell type. Both calcium and zinc were competitive inhibitors of 22Na+ influx in E‐cells (calcium Ki = 105.1±5.2 µM; zinc Ki=46.2±7.8 µM), but the extent to which these divalent cations inhibited monovalent cation transport by each cell type varied. It is concluded that different isoforms of the electrogenic 2Na+/1H+ antiporter may be present in each hepatopancreatic cell type and thereby contribute in differing degrees to the cation regulatory functions performed by the overall organ. J. Exp. Zool. 297A:32–44, 2003. © 2003 Wiley‐Liss, Inc.
Viewing chelonian reproductive ecology through acoustic windows: Cranial and inguinal perspectives
Authors: Henen Brian T. , Hofmeyr Margaretha D.
Published: April 2003

Ultrasonography is a powerful new tool in reproductive physiology and ecology but quantitative evaluations of acoustic window efficacies are necessary to assess methodological accuracy. We evaluated the efficacy of the left inguinal, right inguinal and cranial acoustic windows for detecting ovarian follicles and oviducal eggs in three tortoise species. Incorporating cranial results improved upon inguinal efficacies for detecting follicles in the three species, and for detecting eggs in Chersina angulata, which had small inguinal apertures for its body size. The cranial window provided the best follicle results (highest numbers detected) but the left inguinal window provided the best egg results. This asymmetry was probably due to the primarily posterior position of the oviducts (eggs) and the pliable ovarian sheets allowing follicles to move cranially. The left‐right asymmetry may result from intestinal asymmetry (i.e., between the cecum and descending colon) in obscuring ultrasound transmission or displacing follicles and eggs. Seasonal influences upon efficacies varied with species, partially due to species differences in a) reproductive cycles and b) size and number of follicles and eggs. We attributed other efficacy differences among species to differences in body size and shell morphology, especially the inguinal apertures. Correlation analyses revealed strong individual influences upon window efficacy, suggesting that individuals varied in the position of follicles and eggs and the degree of obfuscation by nonreproductive structures. The paucity of correlations between efficacies and body size reflects the complex interactions of body size, shell morphology, reproductive structures and reproductive cycles on efficacies. J. Exp. Zool. 297A:88–104, 2003. © 2003 Wiley‐Liss, Inc.
Characterization of the effects of vasoactive substances on the bulbus arteriosus of the eel, Anguilla rostrata
Authors: Evans David H. , Harrie Ann C. , Kozlowski Matthew S.
Published: April 2003

The fish bulbus arteriosus (BA) smoothes cardiac output by expanding during cardiac systole and rebounding during diastole, thereby providing constant perfusion of the gills downstream. Published data have demonstrated innervation of the teleost BA and shown that the tension and compliance of the BA responded to vasoactive agonists, such as epinephrine and acetylcholine, suggesting that the BA was more than a mere “windkessel.” To examine vasoactivity in the BA more directly, we measured the responses of isolated tissue rings from the BA of the eel, Anguilla rostrata to a suite of putative vasoactive agonists, which had been shown to affect vascular smooth muscle in a variety of teleosts. The BA of the eel was insensitive to acetylcholine but constricted when endothelin (ET‐1) was applied. Nitric oxide, sodium nitroprusside (SNP; NO donor), natriuretic peptides (NP), and prostaglandin E1 (but not the prostacyclin agonist carbaprostacyclin) produced significant dilation in the BA. Since both ET‐1 and sarafotoxin S6c produced concentration‐dependent constriction, it appears that endothelin receptor B‐type (ETB) receptors (and possibly ETA receptors) are present. The dilation produced by SNP was also concentration dependent, as were the dilations produced by porcine C‐type natriuretic peptide, eel atrial natriuretic peptide (NP receptor agonists), Sulprostone and Butaprost (PGE receptor agonists). Our data demonstrate that the BA of eel is responsive to a variety of vasoactive agonists, suggesting that the BA is under neurohumoral control. The role of agonist‐induced changes in BA tension in fish cardiovascular physiology remains to be determined, as do the specific receptor types involved. J. Exp. Zool. 297A:45–51, 2003. © 2003 Wiley‐Liss, Inc.
Compensation for hypercapnia by a euryhaline elasmobranch: Effect of salinity and roles of gills and kidneys in fresh water
Authors: Choe Keith Patrick , Evans David H.
Published: April 2003

Specimens of the euryhaline elasmobranch, Dasyatis sabina were acclimated to seawater and fresh water, and exposed to normocapnic (air) and hypercapnic (1% CO2 in air) environmental water. Blood pH, P, and [HCO], as well as whole‐animal net‐acid excretion, were measured for up to 24 h of hypercapnia. In a separate experimental series, urine was collected from freshwater acclimated stingrays during 8 h of normocapnia and hypercapnia. Stingrays in both salinities at least partially compensated for the respiratory acidosis by accumulating HCO in their extracellular spaces. The degree of compensation for blood pH was 88.5% in seawater, but only 31.0% in fresh water after 24 h of hypercapnia. Whole‐animal net‐acid excretion was also greater in seawater than in fresh water, as was the increase in extracellular fluid [HCO]. Mean urinary net‐acid excretion rates were slightly negative, and never increased above normocapnic control rates during hypercapnia. Since whole‐animal net‐acid excretion rates increased with blood [HCO], and urinary excretion was always negative, the gills were probably the primary organ responsible for compensation from environmental hypercapnia. The faster, and more complete, compensation for hypercapnia in seawater than in fresh water for this euryhaline elasmobranch is consistent with data for euryhaline teleosts, and probably reflects Na+‐dependent mechanisms of branchial acid excretion. J. Exp. Zool. 297A:52–63, 2003. © 2003 Wiley‐Liss, Inc.
Vascular anatomy of the gills in a high energy demand teleost, the skipjack tuna (Katsuwonus pelamis)
Authors: Olson Kenneth R. , Dewar Heidi , Graham Jeffrey B. , Brill Richard W.
Published: April 2003

Tunas (family: Scombridae, Tribe: Thunnini) exhibit anatomical, physiological, and biochemical adaptations that dramatically increase the ability of their cardiorespiratory systems to transfer oxygen from the water to the tissues. In the present study the vascular anatomy of the skipjack tuna, Katsuwonus pelamis, gill was examined by light and scanning electron microscopic analysis of methyl methacrylate vascular corrosion replicas prepared under physiological pressure. The gill filament contains three distinct blood pathways, respiratory, interlamellar, and nutrient. The respiratory, or arterio‐arterial (AA) pathway, is the site of gas exchange and consists of the afferent and efferent filamental arteries (AFA and EFA) and arterioles (ALA and ELA) and the lamellae. Each ALA in the basal filament supplies ten or more lamellae and they anastomose with their neighbor to form a continuous vascular arcade. Four modifications in the lamellar circulation appear to enhance gas exchange efficiency. 1) The ALA deliver blood directly to the outer margin of the lamellae where unstirred boundary layer effects are predicted to be minimal and water PO2 highest. 2) Pillar cells are closely aligned along the outer boundary of the inlet side and the inner boundary of the outlet side of the lamellae to form multiple distributing and receiving blood channels. 3) Elsewhere in the lamella, pillar cells are aligned to form diagonal channels that direct blood from the outer to the inner lamellar margins, thereby reducing vascular resistance. 4) The lamellar sinusoid is especially widened near the efferent end to augment oxygen saturation of blood flowing through the inner margin. These adaptations, plus the presence of a bow‐shaped interlamellar septum, and a thinned filament core appear to decrease gill vascular resistance and maximize gas‐exchange efficiency. The interlamellar (IL) and nutrient systems originate from post‐lamellar vessels and are arterio‐venous (AV) pathways. IL vessels form an extensive ladder‐like lattice on both sides of the filamental cartilage and are supplied in part by narrow‐bore vessels from the medial wall of the EFA. Their function is unknown. Nutrient vessels are formed from the confluence of a myriad of tortuous, narrow‐bore vessels arising from the basal region of the EFA and from efferent branchial arteries. They re‐enter the filament and eventually drain into the IL system or filamental veins. As these AV pathways are retained despite considerable reduction in filamental tissue, it is evident that they are integral components of other non‐respiratory homeostatic activities of the gill. J. Exp. Zool. 297A:17–31, 2003. © 2003 Wiley‐Liss, Inc.
Synthesis of deuterium‐labeled 3‐O‐methyldopa and 4‐O‐methyldopa
Authors: Perera Aruna , Hyland Keith , Nguyen Hoa K. , Kane Robert R.
Published: April 2003

Concise methods for the synthesis of 4‐hydroxy‐3‐[2H3]‐methoxyphenylalanine (3‐O‐[2H3]‐methydopa) and 3‐hydroxy‐4‐[2H3]‐methoxyphenylalanine (4‐O‐[2H3]‐methydopa) are described. The 3‐O‐[2H3]‐methydopa is a valuable internal standard for the tandem MS quantification of 3‐O‐methyldopa, a metabolite of value in the diagnosis of aromatic l‐amino acid decarboxylase (AADC) deficiency. Copyright © 2003 John Wiley & Sons, Ltd.
Asymmetric epoxidation of digeranyl by cultured cells of Nicotiana tabacum
Authors: Nakagawa Osamu , Shimoda Kei , Izumi Sunsuke , Hirata Toshifumi
Published: April 2003

Asymmetric epoxidation of digeranyl, which is a squalene analog, with cultured cells of Nicotiana tabacum was investigated. Feeding of [8‐3H]‐digeranyl into the cultured cells of N. tabacum resulted in the formation of (3S)‐2,3‐epoxydigeranyl and 6,7‐epoxydigeranyl. It was found that the epoxidation of digeranyl with N. tabacum was highly stereoselective. Copyright © 2003 John Wiley & Sons, Ltd.
Synthesis of tritium labelled L783483 ‐ a PPARδ ligand
Authors: Grue‐Sørensen Gunnar , Høj Nicolaj
Published: April 2003

The potent peroxisome proliferator‐activated receptor (PPAR) δ ligand L783483 (3‐chloro‐4‐(3‐(7‐propyl‐3‐trifluoromethyl‐benzisoxazol‐6‐oxy)propylsulfanyl)phenylacetic acid) has been labelled with tritium via selective tritium/bromine exchange of 5‐bromo‐6‐(3‐bromopropyloxy)‐7‐propyl‐3‐trifluoromethyl‐benzisoxazole. [3H]‐L783483 had a specific activity of 529 GBq/mmol (14.3 Ci/mmol) and a radiochemical purity of 98%. Copyright © 2003 John Wiley & Sons, Ltd.
Chemical and enzymatic synthesis of tritium labelled coenzymes
Authors: Sidorov G. V. , Zverkov Yu. B. , Shram S. I. , Lazurkina T. Yu. , Myasoedov N. F.
Published: April 2003

Details of the synthesis of tritium labelled co enzymes‐nicotinamide adenine dinucleotide and coenzyme A by isotope exchange and enzymatic reactions are reported. It was established, that among the investigated chemical reactions, the most effective is solid state isotope exchange with gaseous tritium. This method was used to produce [3H] nicotinamide adenine dinucleotide (111 Ci/mmol), [3H] coenzyme A (3.9 Ci/mmol) and D‐[G‐3H] pantothenic acid (43 Ci/mmol). It was shown that most of the tritium in the labeled nicotinamide adenine dinucleotide and coenzyme A was localized in the nicotinamide (98%) and adenine (89%) sites, respectively. For synthesis of coenzymes labelled with tritium at other sites we developed enzymatic methods which used labelled precursors. Optimum conditions for enzymatic synthesis of [adenine‐3H] nicotinamide adenine dinucleotide from [2,8‐3H] ATP and [pantothenate‐3H] coenzyme A from D‐[G‐3H] pantothenic acid were determined. The tritium labelled acetyl coenzyme A was synthesized by acetylation of labelled coenzyme A with acetic anhydride. The methods chosen allow one to produce tritium labelled coenzymes at high specific activity. Copyright © 2003 John Wiley & Sons, Ltd.
[14C] and [3H]‐labelling of Ragaglitazar: A dual acting PPARα and PPARγ agonist with hypolipidemic and anti‐diabetic activity
Authors: Kristensen Jesper B. , Johansen Steen K. , Valsborg Jacob S. , Martiny Lars , Foged Christian
Published: April 2003

Currently, Ragaglitazar is being developed as a drug for the treatment of hyperglycaemia and hyperlipidemia in patients with type 2 diabetes. Here, we report the labelling of Ragaglitazar with carbon‐14 and tritium for in vivo and in vitro investigations. Two different carbon‐14 labelled as well as two different tritium labelled tracers of Ragaglitazar were synthesised. The carbon‐14 label was introduced from either ethyl bromo[2‐14C]acetate (5 steps/33% overall yield) or [U‐14C]phenoxazine (4 steps/48% overall yield). Tritium was incorporated either by catalytic tritiation of an alkene precursor followed by chiral HPLC separation (2 steps/17% overall yield) or by catalytic tritium–halogen exchange of an aryl bromide precursor (2 steps/68% overall yield). Copyright © 2003 John Wiley & Sons, Ltd.
Application of 1‐butyl‐3‐methylimidazolium hexafluorophosphate to Ir(I)‐catalyzed hydrogen isotope exchange labelling of substrates poorly soluble in dichloromethane
Authors: Salter Rhys , Bosser Isabelle
Published: April 2003

Substrate solubility remains a major limitation in Ir(I)‐catalyzed isotopic hydrogen exchange labelling. In the search for an alternative to the solvent dichloromethane, which is critical to the success of the reaction, we examined a series of ionic liquids for their suitability. Commercially available 1‐butyl‐3‐methylimidazolium hexafluorophosphate (abbreviated to [BMI][PF6]) was found to support efficient deuterium and tritium exchange labelling of N‐(4‐methoxyphenyl)‐N‐methyl benzamide 1 under standard conditions. The solvent dissolves both polar hydroxyl and carboxylic acid substituted acetanilides, providing isotopomers in unprecedentedly high deuterium incorporation as compared to dichloromethane. We report the application of [BMI][PF6] and its potential for extending the scope of Ir(I)‐catalyzed H/T exchange to more polar compounds. Copyright © 2003 John Wiley & Sons, Ltd.
Über die gültigkeit des viskositätsgesetzes bei polyoxydecansäuren
Authors: Staudinger Von H. , Berndt Fr.
Published: April 2003

Es werden fünf Polyoxydecansäuren vom osmotischen Molekulargewicht 5000 bis 13 000 beschrieben, bei denen die beiden Endgruppenmolekulargewichte die gleiche Größe haben und die danach unverzweigte Moleküle haben. Da auch das viskosimetrische Molekulargewicht mit diesen Werten übereinstimmt, so wird auf die Gültigkeit des Viskositätsgesetzes geschlossen.

Eine Gruppe von anderen Polyoxydecansäuren von gleichem und höherem Molekulargewicht hat verzweigte Moleküle, da das Endgruppenmolekulargewicht, bestimmt aus dem Carboxylgruppengehalt, niedriger ist als das osmotische Molekulargewicht und das andere Endgruppenmolekulargewicht. Die viskosimetrischen Molekulargewichte stimmen bei diesen verzweigten Polyestern nicht mit den Endgruppen molekulargewichten überein.

Die Fasern aus unverzweigten und verzweigten Polyestern zeigen bemerkenswerte Unterschiede in der Festigkeit.