bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating the TNP‐OVA and direct popliteal lymph node assays for the detection of immunostimulation by drugs associated with anaphylaxis in humans
Authors: Gutting Bradford W. , Updyke Lawrence W. , Amacher David E.
Published: August 2002

Using current animal models, it is not possible to identify low‐molecular‐weight compounds (LMWCs) that are likely to be associated with anaphylaxis. It is generally accepted that the ultimate effector mechanism involves drug‐induced IgE antibody. The objective of the present study was to determine if diclofenac, zomepirac and glafenine, which are associated with anaphylaxis in humans, have immunostimulating potential in the murine TNP‐OVA (trinitrophenyl‐ovalbumin) popliteal lymph node assay (PLNA), and more specifically to determine if the immunostimulation caused by these LMWCs results in IgE antibody production. These LMWCs were chosen because both zomepirac and glafenine were removed from the market due to high association with anaphylaxis, and diclofenac, which remains on the market, is frequently associated with anaphylaxis. In addition to conducting a TNP‐OVA PLNA, the immunostimulating potential of these compounds was examined in the direct PLNA. When co‐administered with TNP‐OVA, all three LMWCs caused dose‐dependent (0.25, 0.50, 1.00 and 1.25 mg) increases in popliteal lymph node (PLN) weight and cellularity that were observed beginning with the 0.25‐mg dose. In addition, beginning with the 0.25‐mg dose, all three compounds caused dose‐dependent increases in TNP‐OVA specific IgM and IgG1 antibody‐forming cells (AFCs). Diclofenac induced an isotype switch and caused a dose‐dependent increase in the number of IgE AFCs with no detectable IgG2a AFCs and minimal high‐dose‐only IgG2b AFCs. Zomepirac induced IgE, IgG2a and IgG2b AFCs following the injection of 0.50 mg only, and glafenine induced IgE, IgG2a and IgG2b AFCs following the injection of 0.50–1.00 mg. In the direct PLNA, diclofenac caused dose‐dependent increases in PLN weight and cellularity that were observed beginning with dose of 0.50 mg, whereas zomepirac failed to increase any PLN parameter and glafenine only increased the PLN weight. These results suggest that diclofenac, zomepirac and glafenine are immunostimulating LMWCs in the TNP‐OVA PLNA with the potential to induce IgE antibody against a co‐administered hapten‐conjugate. Furthermore, these results suggest that the TNP‐OVA PLNA offered significant advantages over the direct PLNA. Although it is not realistic to suggest that a single assay, based on a low number of test compounds, can identify all LMWCs with the potential to cause anaphylaxis in humans, these observations do demonstrate the potential utility of the PLNAs in examining LMWC‐induced immunomodulation and support further development and investigation of the assays. Copyright © 2002 John Wiley & Sons, Ltd.
Airway reactivity response to aged carbon–graphite/epoxy composite material smoke
Authors: Kimmel Edgar C. , Reboulet James E. , Courson David L. , Still Kenneth R.
Published: August 2002

Exposure of na&ıuml;ve guinea pigs for a total of 30 min to aged smoke from pyrolysis of 5, 10 and 100 g of carbon–graphite/epoxy‐advanced composite material (cgeCM) elicited changes in the ventilation and breathing pattern reminiscent of an acute, asthmatic episode. The severity of these responses was dose related. Although breathing pattern changes were not definitive of stimulation by a single type of respiratory irritant, non‐dimensional indices derived from breath structure appeared to be characteristic of bronchoconstriction possibly complicated by CO2‐stimulated ventilation. The highest exposure concentration also elicited convulsions in the animals, which may or may not be related to the airway reactivity (AR) response. Upon treatment with fresh air, breathing returned to normal. However, this recovery was transient with some respiratory parameters returning to abnormal levels, possibly indicating a rebound or delayed component of the response. Filtration of particulate material from the smoke moderated but did not eliminate the AR response. Animals exposed to diluted smoke from the pyrolysis of 2 g of cgeCM showed no remarkable changes in breathing or ventilation, suggesting that there may be a threshold for aged cgeCM smoke‐elicited AR response. Published in 2002 by John Wiley & Sons, Ltd.
Effect of zinc on hepatic lipid peroxidation and antioxidative enzymes in ethanol‐fed rats
Authors: Pathak A. , Mahmood A. , Pathak R. , Dhawan D.
Published: August 2002

A 3‐ml aliquot of 30% ethanol was fed daily to normal as well as zinc‐treated (227 mg l−1) rats for periods of 2, 4 and 8 weeks. A highly significant increase in the levels of hepatic lipid peroxidation was observed in ethanol‐fed rats after 4 and 8 weeks of treatment. On the other hand, the levels of lipid peroxidation came down significantly following ethanol feeding to zinc‐treated rats. The activities of glutathione peroxidase (GPx), catalase and superoxide dismutase (SOD) in liver were elevated significantly after ethanol administration to rats for durations of 2, 4 and 8 weeks. Interestingly, zinc treatment to rats given ethanol was able to bring down the elevated levels of SOD, catalase and GPx to within normal limits, However, zinc administration alone did not cause any significant alteration in the activities of these antioxidative enzymes. Copyright © 2002 John Wiley & Sons, Ltd.
Cement–cement interface strength: Influence of time to apposition
Authors: Park Sang‐Hyun , Silva Mauricio , Park Jong‐Seok , Ebramzadeh Edward , Schmalzried Thomas P.
Published: August 2002

Cement–cement interfaces were created under simulated operating‐room conditions. In order to analyze the effect of time to apposition on interface strength, two cement surfaces were brought together 1, 2, 4, and 6 min after 1 min of mixing and 45 s of waiting. Cement–cement interface strength was evaluated with the use of a three‐point bending to failure test. Scanning electron microscopy (SEM) images of the failed interface were obtained. The mean interface strength decreased when the cement–cement interface was time delayed. Compared to bulk cement, interface strength in time‐delayed groups decreased 8% after 1‐min delay (p=.037), 18% after 2‐min delay (p=.0004), 20% after 4‐min delay (p=.0005), and 42% after 6‐min delay (p<.0001). No statistically significant differences in interface strength were found between the 2‐ and 4‐min delayed groups (p=.73). SEM images revealed that after 6‐min delay, up to 50% of the cement surface can remain unbonded, explaining the decrease in strength of the cement–cement interface as a function of time to apposition. This laboratory study indicates that time to apposition plays a critical role in cement–cement interface strength. If any cementing technique involves the joining of two cement surfaces, it is recommended that the two cement surfaces be mated together within 5 min and 45 s after the start of mixing (1 min mixing; 45 s waiting; 4 min delay), in order to obtain a strong cement–cement interface bond. Delay beyond this can result in substantial reduction in the strength of the cement–cement interface bond. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res (Appl Biomater) 58: 741–746, 2001
The relationship between stress, porosity, and nonlinear damage accumulation in acrylic bone cement
Authors: Murphy B. P. , Prendergast P. J.
Published: August 2002

The long‐term survival of cemented hip replacements depends on the ability of the cemented fixation to resist fatigue damage. Damage has been assumed to accumulate linearly (Miner's law) even though it is unlikely to be the case in such a porous brittle material. This study addresses the nonlinear stress‐dependent nature of fatigue damage accumulation in acrylic bone cement. Specimens were subjected to a zero‐to‐tension fatigue load in water at 37°C. A total of 15 specimens were tested, i.e., five specimens at each of three stress levels. The specimens were cyclically loaded to a certain fraction of their fatigue lives and the amount of microcracking present at that time was quantified by counting each crack and measuring its length. This procedure was repeated until the specimen failed. A total of 801 cracks formed in the 15 specimens. All cracks were found to initiate at pores. Crack propagation directions were distributed normally about the direction perpendicular to the applied load at the lower stress levels, but at higher stress, the distribution tended to be broader. At higher stresses, more cracks were produced per pore. The damage accumulation process in acrylic bone cement was found to be nonlinear with the degree of nonlinearity increasing with stress. Furthermore, great variability was found which was attributed to the differences in porosity between specimens. A power law equation is given which describes the predicted relationship between damage accumulation and number of loading cycles as a function of the stress level. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 646–654, 2002
von Hippel‐Lindau tumor suppressor protein represses platelet‐derived growth factor B‐chain gene expression via the Sp1 binding element in the proximal PDGF‐B promoter
Authors: Rafty Louise A. , Khachigian Levon M.
Published: August 2002

VHL is the causative gene for von Hippel‐Lindau disease and sporadic clear cell renal cancer. It has been shown that pVHL can suppress the expression of certain genes that are overexpressed in renal carcinomas. One such gene is that encoding the potent mitogen and chemoattractant, platelet‐derived growth factor B‐chain (PDGF‐B). The regulatory mechanisms underlying pVHL suppression of PDGF‐B expression, however, are completely unknown. This understanding would shed vital light on the control of growth factor gene expression by this tumor suppressor. Here we report that pVHL can repress both endogenous steady‐state PDGF‐B mRNA expression and PDGF‐B promoter‐dependent transcription in WKY12‐22 cells. Transient transfection analysis utilizing PDGF‐B promoter‐chloramphenicol acetyl transferase (CAT) reporter constructs revealed that pVHL inhibition of PDGF‐B expression is mediated via the Sp1‐binding element in the proximal region of the PDGF‐B promoter. Recent studies have demonstrated a physical interaction between pVHL and Sp1, which activates the PDGF‐B promoter. We show that Sp1 can rescue PDGF‐B promoter activity and endogenous PDGF‐B mRNA expression from pVHL repression. These findings thus demonstrate a pivotal role for Sp1 in pVHL inhibition of PDGF‐B transcription. J. Cell. Biochem. 85: 490–495, 2002. © 2002 Wiley‐Liss, Inc.
Extracellular matrix regulates alpha s1‐casein gene expression in rabbit primary mammary cells and CCAAT enhancer binding protein (C/EBP) binding activity
Authors: Jolivet Geneviève , Meusnier Chantal , Chaumaz Gilles , Houdebine Louis‐Marie
Published: August 2002

Previous studies have shown that both the signal transducer and activator of transcription 5 (STAT5) and the CCAAT enhancer binding proteins (C/EBPs) are involved in the regulation of casein gene expression by mammary epithelial cells. Prolactin (Prl) activation of STAT5 is necessary for casein gene expression. The extracellular matrix (ECM) regulates also casein gene expression. Here, we have investigated whether ECM regulates C/EBPs activity in primary rabbit mammary epithelial cells. Isolated primary mammary cells were cultured on plastic or on floating collagen I gel. Prolactin induced αs 1‐casein gene expression when cells were cultured on collagen but not on plastic. It is noteworthy that activated STAT5 was detected in both culture conditions. Several STAT5 isoforms (STAT5a, STAT5b, and other STAT5 related isoforms, some with lower molecular weight than the full‐length STAT5a and STAT5b) were detected under the different culture conditions. However, their presence was not related to the expression of αs 1‐casein gene. The binding of nuclear factors to a C/EBP specific binding site and the protein level of C/EBPβ differed in cells cultured on plastic or on collagen but these parameters were not modified by Prl. This suggests that C/EBP binding activity was regulated by ECM and not by Prl. Interestingly, these modifications were correlated to the expression of the αs 1‐casein gene. Hence, the activation of the αs 1‐casein gene expression depends on two independent signals, one delivered by Prl via the activation of STAT5, the other delivered by ECM via C/EBP. J. Cell. Biochem. 82:371–386, 2001. © 2001 Wiley‐Liss, Inc.
Inhibitory effect of regucalcin on protein phosphatase activity in the nuclei of rat kidney cortex
Authors: Morooka Yoshiko , Yamaguchi Masayoshi
Published: August 2002

The role of regucalcin, which is a regulatory protein of calcium signaling, in the regulation of protein phosphatase activity in the nuclei of rat kidney cortex was investigated. Protein phosphatase activity towards phosphotyrosine, phosphoserine, and phosphothreonine was found in the nuclei. The enzyme activity towards three phosphoamino acids was significantly increased by the addition of calcium chloride (10–50 μM) in the enzyme reaction mixture. This increase was significantly inhibited by trifluoperazine (25 or 50 μM), an antagonist of calmodulin. The presence of regucalcin (50 or 100 nM) in the enzyme reaction mixture caused a significant decrease in protein phosphatase activity towards three phosphoamino acids. This effect was also seen in the presence of calcium (25 μM) and/or calmodulin (5 μg/ml). Protein phosphatase activity towards three phosphoamino acids was significantly increased in the presence of anti‐regucalcin monoclonal antibody (25 or 50 ng/ml) in the enzyme reaction mixture. This effect was completely blocked by the addition of regucalcin (100 nM). The effect of antibody (25 ng/ml) in increasing protein phosphatase activity towards phosphotyrosine was significantly inhibited by vanadate (10−4 M). Also, the antibody's effect towards phosphoserine and phosphothreonine was significantly inhibited by cyclosporin A (10−5 M). Endogenous regucalcin was found in the nuclei of rat kidney cortex using Western blot analysis. Nuclear regucalcin level was significantly reduced by the administration of saline (0.9% NaCl) for seven days in rats. Protein phosphatase activity towards three phosphoamino acids was significantly decreased by saline administration. The effect of anti‐regucalcin monoclonal antibody (25 ng/ml) in increasing protein phosphatase activity towards three phosphoamino acids was weakened in the renal cortex nuclei of saline‐administrated rats. The present study demonstrates that endogenous regucalcin plays a suppressive role in the regulation of protein phosphatase activity in the nuclei of rat kidney cortex cells. © 2001 Wiley‐Liss, Inc.
Semiautomatic sequence‐specific assignment of proteins based on the tertiary structure—The program st2nmr
Authors: Pristovšek Primož , Rüterjans Heinz , Jerala Roman
Published: August 2002

The sequence‐specific assignment of resonances is still the most time‐consuming procedure that is necessary as the first step in high‐resolution NMR studies of proteins. In many cases a reliable three‐dimensional (3D) structure of the protein is available, for example, from X‐ray spectroscopy or homology modeling. Here we introduce the st2nmr program that uses the 3D structure and Nuclear Overhauser Effect spectroscopy (NOESY) peak list(s) to evaluate and optimize trial sequence‐specific assignments of spin systems derived from correlation spectra to residues of the protein. A distance‐dependent target function that scores trial assignments based on the presence of expected NOESY crosspeaks is optimized in a Monte Carlo fashion. The performance of the program st2nmr is tested on real NMR data of an α‐helical (cytochrome c) and β‐sheet (lipocalin) protein using homology models and/or X‐ray structures; it succeeded in completely reproducing the correct sequence‐specific assignments in most cases using 2D and/or 15N/13C Nuclear Overhauser Effect (NOE) data. Additionally to amino acid residues the program can also handle ligands that are bound to the protein, such as heme, and can be used as a complementary tool to fully automated assignment procedures. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 335–340, 2002
Use of exchange maximization to generate starting vectors for self‐consistent field calculations on metal cluster/adsorbate systems
Authors: Buenker R. J. , Whitten J. L. , Izgorodina E. I. , Liebermann H.‐P. , Kokh D. B.
Published: August 2002

Localized molecular orbitals (LMOs) derived from exchange maximization with respect to all atom‐centered basis functions in the basis set are shown to generate a good starting electronic field for self‐consistent field calculations on extended systems such as metal clusters, for which well‐defined chemical bonds are not present. Examples studied are a cluster of 20 Ni atoms and the Pt97CO, Ag43/H3CNON, Ag91/H2CO, and vinylidene/Ni metal cluster plus adsorbate systems. It is also shown that improved starting vectors can be obtained by remixing a subset of the LMOs with the largest exchange eigenvalues through diagonalization of the Fock matrix computed with a null electronic field. Employing only a subset of the exchange‐maximized LMOs in the first iterations, and then gradually expanding the space in which the diagonalizations are carried out in succeeding cycles, is shown to be an effective means of guiding the SCF procedure to the converged full‐basis solution. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 943–949, 2002
Intra‐ and intermolecular interactions in crystals of polar molecules. A study by the mixed quantum mechanical/molecular mechanical SCMP‐NDDO method
Authors: Ferenczy György G. , Ángyán János G.
Published: August 2002

Stabilization energies of crystals of polar molecules were calculated with the recently developed NDDO‐SCMP method that determines the wave function of a subunit embedded in the symmetrical environment constituted by the copies of the subunit. The total stabilization energies were decomposed into four components. The deformation energy is the difference between the energy of the molecule in the geometries adopted in the crystal on the one hand, and in vacuo, on the other hand. Further energy components are derived from the molecular geometry found in the crystal phase. The electrostatic component is the interaction energy of the molecule with the crystal field, corresponding to the charge distribution obtained in vacuo. The polarization component is the energy lowering resulted in the self‐consistent optimization of the wave function in the crystal field. The rest of the stabilization energy is attributed to the dispersion–repulsion component, and is calculated from an empirical potential function. The major novelty of this decomposition scheme is the introduction of the deformation energy. It requires the optimization of the structural parameters, including the molecular geometry, the intermolecular coordinates, and the cell parameters of the crystal. The optimization is performed using the recently implemented forces in the SCMP‐NDDO method, and this new feature is discussed in detail. The calculation of the deformation energy is particularly important to obtain stabilization energies for crystals in which the molecular geometry differs considerably from that corresponding to the energy minimum of the isolated molecule. As an example, crystals of diastereoisomeric salts are investigated. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1679–1690, 2001
Simulating enzyme reactions: Challenges and perspectives
Authors: Field Martin J.
Published: August 2002

Elucidating how enzymes enhance the rates of the reactions that they catalyze is a major goal of contemporary biochemistry, and it is an area in which computational and theoretical techniques can make a major contribution. This article outlines some of the processes that need to be investigated if enzyme catalysis is to be understood, reviews the current state‐of‐the‐art in enzyme simulation work, and highlights challenges for the future. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 48–58, 2002
Double coverings of 2‐paths by Hamilton cycles*
Authors: Kobayashi Midori , Mutoh Nobuaki , Kiyasu‐Zen'iti  , Nakamura Gisaku
Published: August 2002

A double Dudeney set in Kn is a multiset of Hamilton cycles in Kn having the property that each 2‐path in Kn lies in exactly two of the cycles. A double Dudeney set in Kn has been constructed when n ≥ 4 is even. In this paper, we construct a double Dudeney set in Kn when n ≥ 3 is odd. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 195–206, 2002; Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/jcd.10003
What is an infinite design?
Authors: Cameron Peter J. , Webb Bridget S.
Published: August 2002

It is usually assumed that an infinite design is a design with infinitely many points. This encompasses a myriad of structures, some nice and others not. In this paper we consider examples of structures that we would not like to call designs, and investigate additional conditions that exclude such anomalous structures. In particular, we expect a design to be regular, the complement of a design to be a design, and a t‐design to be an s‐design, for all 0 < s ≤ t. These are all properties that can be taken for granted with finite designs, and for infinite Steiner systems. We present a new definition of an infinite t‐design, and give examples of structures that satisfy this definition. We note that infinite designs considered in the literature to date satisfy our definition. We show that infinite design theory does not always mirror finite design theory, for example there are examples of designs with υ > b. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 79–91, 2002; DOI 10.1002/jcd.10005
Some Hadamard designs with parameters (71,35,17)
Authors: Crnković Dean , Held Dieter
Published: August 2002

Up to isomorphisms there are precisely eight symmetric designs with parameters (71, 35, 17) admitting a faithful action of a Frobenius group of order 21 in such a way that an element of order 3 fixes precisely 11 points. Five of these designs have 84 and three have 420 as the order of the full automorphism group G. If |G| = 420, then the structure of G is unique and we have G = (Frob21 × Z5):Z4. In this case Z(G) = 〈1〉, G′ has order 35, and G induces an automorphism group of order 6 of Z7. If |G| = 84, then Z(G) is of order 2, and in precisely one case a Sylow 2‐subgroup is elementary abelian. © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 144–149, 2002; DOI 10.1002/jcd.996
Quantification of antigen‐reactive T cells by a modified ELISPOT assay based on freshly isolated blood dendritic cells
Authors: Schmitz M. , Rohayem J. , Paul R. , Weigle B. , Stein A. , Rieber E.P.
Published: August 2002

The enzyme‐linked immunospot (ELISPOT) assay has become a widely employed method for quantification of antigen‐reactive T lymphocytes. In recent years, various types of antigen‐presenting cells (APCs) have been tested as stimulator cells in ELISPOT protocols to achieve a highly sensitive and rapid assay which is not impaired by a marked nonspecific cytokine release. However, the currently available APCs still have disadvantages, such as significant background reactivities, limited sensitivity, and time‐consuming preparation procedures. Recently, we succeeded in defining a novel subpopulation of circulating dendritic cells (DCs) that can easily be prepared from human blood. These M‐DC8+ DCs proved to be very effective in the induction of antigen‐specific T cell responses. In the present study we provide evidence that M‐DC8+ DCs are particularly well suited as APCs for the detection of antigen‐specific CD8+ T cells after challenge with viral or tumor peptides in ELISPOT assays. In addition, protein‐loaded M‐DC8+ DCs proved to be quite efficient in the presentation of MHC class II‐bound peptides, thus allowing the determination of frequencies of antigen‐reactive CD4+ T cells. The use of M‐DC8+ DCs as stimulator cells can improve the ELISPOT assay by combining high sensitivity, rapidity, and low background reactivity. J. Clin. Lab. Anal. 16:30–36, 2002. © 2002 Wiley‐Liss, Inc.
Purification of activins from androgen‐independent Shionogi carcinoma cells demonstrates enhanced expression of activin βB‐subunit under androgen‐depleted cell conditions in vitro and in vivo
Authors: Tanaka Akira , Hasegawa Yoshihisa , Hakamata Yoji , Kamiakito Tomoko , Kuriki Ken , Yoshida Hiroki , Fukayama Masashi
Published: August 2002

Here, we report characterization of growth factors secreted from androgen‐independent mouse mammary Shionogi carcinoma cells. Previous isolation of fibroblast growth factor 8 (FGF8) from androgen‐dependent Shionogi carcinoma SC‐3 cells prompted us to characterize growth factors secreted from the androgen‐independent cells. After several purification procedures, mitogens for NIH3T3 cells from the androgen‐independent cells were identified as activins on the grounds that activin βA‐ and βB‐subunits are detected in the active fractions by Western blotting and that the growth‐promoting effects by the active fractions are specifically inhibited in the presence of follistatin. In addition, exogenous activins, but not inhibin, stimulated the growth of NIH3T3 cells in a dose‐dependent manner. Interestingly, transcripts of activin βB‐subunit were predominantly found in the androgen‐independent cells while its βA‐subunit was universally expressed in both androgen‐dependent and ‐independent Shionogi carcinoma cells. In concordant with this in vitro finding, transcripts of activin βB‐subunit were enhanced in murine prostates after castration. Therefore, expression of activin βB‐subunit, but not its βA‐subunit, is likely to be related with androgen‐depleted cell conditions in prostates, and possibly in androgen‐related cancers. © 2001 Wiley‐Liss, Inc.
Cytosolic phospholipase A2 activity during the ongoing cell cycle
Authors: van Rossum Gerda S.A.T. , Vlug Angela S. , van den Bosch Henk , Verkleij Arie J. , Boonstra Johannes
Published: August 2002

Cytosolic phospholipase A2 (cPLA2) is of special interest because it selectively releases arachidonic acid from membrane phospholipids. Arachidonic acid has been implicated to play an important role in various cellular responses. Recently arachidonic acid release and prostaglandin synthesis have been shown to be cell cycle dependent and therefore the activity of cPLA2 during the ongoing cell cycle was investigated, using the mitotic shake off method for cell synchronisation. cPLA2 activity was high in mitotic cells and decreased rapidly in the early G1 phase. A strong increase in activity was measured following the G1/S transition in both neuroblastoma and Chinese hamster ovary cells. The changes in activity were not due to a difference in cPLA2 expression but due to phosphorylation of cPLA2. Phosphorylation of cPLA2 occurs through MAPK since the use of a specific MAPK kinase inhibitor and serum depletion of synchronised cells inhibited cPLA2 activity. © 2001 Wiley‐Liss, Inc.
Sonographic detection of multiple brain abscesses in a newborn with IgA deficiency
Authors: Rožmanić Vojko , Ahel Vladimir , Dessardo Sandro , Flajšman‐Raspor Sanja , Franulović Jadranka , Gazdik Miljen
Published: August 2002

We report the case of a neonate with selective IgA deficiency and multiple brain abscesses diagnosed with sonography. Brain sonography revealed multiple abscesses in the left hemisphere; the abscesses ranged from 10 to 20 mm. Cultures obtained from the cerebrospinal fluid and blood were positive for Proteus mirabilis. The neonate responded promptly to broad‐spectrum antibiotic therapy and had no neurologic sequelae. Because IgA deficiency is associated with infections, we believe it was a predisposing factor for the brain abscesses. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:479–481, 2001.
Sonographic findings of tuberculous thyroiditis in a patient with Behçet's syndrome
Authors: Chung Sun Yang , Oh Ki Keun , Chang Hang Seok
Published: August 2002

We report a case of tuberculous thyroiditis in a woman with Behçet's syndrome. The initial physical examination in May 1998 revealed multiple soft, nontender, mobile lymph nodes, each measuring less than 1 cm, in the left lower internal jugular chain. Sonography performed in February 2000 showed multiple small (< 1 cm), oval lymph nodes, each with an intact fatty hilum, in the left lower internal jugular chain; the thyroid gland appeared normal. Follow‐up sonography 6 months later showed multifocal, heterogeneous, hypoechoic lesions with ill‐defined margins in both lobes of the thyroid and several small, oval lymph nodes, each with an intact fatty hilum, in the left lower internal jugular chain. Fine‐needle aspiration was performed on the largest thyroid lesion, and cytologic analysis of the aspirate revealed a small number of epithelioid histiocytes in a necrotic background, which was suggestive of tuberculosis. Follow‐up sonography after 3 months of antituberculosis chemotherapy showed that the thyroid lesions had resolved. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:184–188, 2002; DOI 10.1002/jcu.10041
Ciliary neurotrophic factor increases the survival of magnocellular vasopressin and oxytocin neurons in rat supraoptic nucleus in organotypic cultures†
Authors: Rusnak Milan , House Shirley B. , Arima Hiroshi , Gainer Harold
Published: August 2002

Organotypic cultures of the rat hypothalamus are very useful models for the long‐term study of parvocellular vasopressin (VP) neurons in the paraventricular (PVN) and suprachiasmatic (SCN) nuclei. However, they do not preserve significant numbers of VP magnocellular neurons (VP‐MCNs) in either the PVN or the supraoptic nucleus (SON). Vutskits et al. [(1998) Neuroscience 87:571–582] reported that ciliary neurotrophic factor (CNTF) was a selective survival factor for rat VP‐MCNs in organotypic cultures of the rat hypothalamic paraventricular nucleus (PVN). We examined the effects of CNTF on the survival of these neurons in rat and mouse SONs. CNTF (10 ng/ml) in the culture media increased the survival of VP‐MCNs by 6‐fold and OT‐MCNs by 3‐fold. In the mouse, both OT‐ and VP‐MCNs survive very well in organotypic cultures under standard culture conditions and the addition of CNTF had no further effect. Consistent with these results, in situ hybridization showed substantially higher levels of VP‐ and OT‐mRNA in rat PVNs and SONs in the presence of CNTF, but produced no changes in these nuclei in the mouse. The optimum period for the survival effect of CNTF on MCNs in the rat hypothalamic cultures was in the first 7–10 days of culture and this effect is maintained for at least 5 additional days if CNTF is then removed from the medium. Therefore, using CNTF in the culture media can provide an opportunity for long‐term studies of rat VP‐ and OT‐MCNs in SONs in organotypic cultures. Microsc. Res. Tech. 56:2002, 2002. © 2002 Wiley‐Liss, Inc.
Multiple connexins localized to individual gap‐junctional plaques in human myometrial smooth muscle
Authors: Kilarski Wincenty M. , Rothery Stephen , Roomans Godfried M. , Ulmsten Ulf , Rezapour Masoumeh , Stevenson Shirley , Coppen Steven R. , Dupont Emmanuel , Severs Nicholas J.
Published: August 2002

The synchronous contractions of the uterus in labour depend on electrical coupling of myometrial smooth muscle cells by gap junctions. In the human myometrium, gap junctions are scarce in the non‐pregnant uterus, but become abundant at term in preparation for labour. We have previously demonstrated that in the human myometrium at term, three different gap‐junctional proteins are expressed, connexins 43, 45, and 40. These connexins are known to have distinctive functional capacities in in vitro expression systems but whether, in the human myometrium in vivo, they are co‐assembled into the same gap junction or form different types of gap junction has previously been unclear. By applying triple immunogold labelling to sections of Lowicryl‐embedded tissue for electron microscopy, together with complementary immunoconfocal microscopy, we demonstrate here that connexins 43, 45, and 40 are commonly present as mixtures within the same gap‐junctional plaque. While all gap junctions contain connexin43, the relative signal for each connexin type varies between individual junctions. The presence within single gap‐junctional plaques of three different connexins, each with the potential for conferring distinctive channel properties, suggests an inherent versatility for modulation of smooth muscle cell intercellular communication properties during human parturition. Microsc. Res. Tech. 54:114–122, 2001. © 2001 Wiley‐Liss, Inc.
Thyroxine induces transitions in red muscle kinetics and steady swimming kinematics in rainbow trout (Oncorhynchus mykiss)
Authors: Coughlin David J. , Forry Jennifer A. , McGlinchey Shannon M. , Mitchell Jason , Saporetti Katherine A. , Stauffer Karen A.
Published: August 2002

During normal development, rainbow trout undergo a shift in red muscle contraction kinetics and swimming kinematics. Young trout parr have faster muscle kinetics and faster tailbeat frequency during swimming than older, larger juvenile trout. In this study, the thyroid hormone thyroxine (T4) was used to induce these changes in trout parr. This allowed a comparison of swimming kinematics, through the use of video analysis and electromyography, and red muscle contractile properties, through the use of in vitro muscle preparations, between natural parr and same‐sized induced juveniles. The red muscle of natural parr has faster contractile properties than induced juveniles, including faster twitch time and a faster maximum shortening velocity (Vmax). Further, natural parr swim with faster tailbeat frequencies than induced juveniles. The results suggest that the natural shift in red muscle contraction kinetics observed during parr‐smolt transfomation in trout directly affects swimming behavior in these fish. Also, thyroid hormones appear to induce a shift towards slower isoforms of the muscle protein myosin heavy chain (MHC), a result distinct from work on rats where thyroid hormones induce shifts towards faster forms of MHC. J. Exp. Zool. 290:115–124, 2001. © 2001 Wiley‐Liss, Inc.
Myosin heavy chain expression in the red, white, and ventricular muscle of juvenile stages of rainbow trout
Authors: Weaver Frances E. , Stauffer Karen A. , Coughlin David J.
Published: August 2002

Juvenile stages of rainbow trout, smaller parr and older juveniles, termed smolts, show differences in red muscle contractile properties: parr red muscle has faster kinetics and a faster maximum shortening velocity than smolt red muscle. A developmental reduction in the number of MHC isoforms as detected by SDS‐PAGE between parr and smolt has also been observed. To investigate whether this shift in contractile kinetics results from differential gene expression, three different MHC cDNA fragments, one each from red, white, and ventricular muscle, were identified. The red muscle and ventricular forms are novel MHCs, and the white muscle form is identical to a published MHC from adult trout white muscle. Tissue and developmental stage‐specific expression patterns of these MHC isoforms were examined using isoform‐specific RT‐PCR. Ventricular muscle typically showed only the ventricular form; 60% parr and 80% smolts expressed the ventricular form only. Approximately half of the white muscle samples of either parr or smolts, 58% and 50%, respectively, expressed only white muscle MHC. Red muscle samples were the most heterogeneous, with red muscle MHC found in combination with either the white or ventricular form or both. Combining samples from the anterior and posterior, 8% of parr red muscle samples expressed solely the red muscle MHC form, and 30% of smolt red muscle samples expressed the red muscle form alone. Variations in the relative contribution of each MHC to the red muscle of parr and smolt may explain observed differences in protein composition and contractile properties. J. Exp. Zool. 290:751–758, 2001. © 2001 Wiley‐Liss, Inc.
Synthesis and characterization of [2‐3H] (1R,2S)‐ (−)‐2‐amino‐1,2‐diphenylethanol
Authors: Egan Judith A. , Filer Crist N.
Published: August 2002

(R)‐(−) Benzoin oxime 2 was catalytically tritiated to afford [2‐3H] (1R,2S)‐(−)‐2‐amino‐1,2‐diphenylethanol 1 in 92% ee. Copyright © 2001 John Wiley & Sons, Ltd.
Highly efficient synthesis of [11C]Me‐QNB, a selective radioligand for the quantification of the cardiac muscarinic receptors using PET
Authors: Dolle Frédéric , Hinnen Françoise , Vaufrey Françoise , Demphel Stéphane , Bramoulle Yann , Fournier Denis , Ponchant Michel , Valette Héric , Crouzel Christian
Published: August 2002

Me‐QNB (N‐methyl‐quinuclidin‐3‐yl benzilate or N‐methyl‐quinuclidin‐3‐yl diphenylhydroxy acetate) is a hydrophilic, non‐metabolized and highly specific muscarinic acetylcholinergic antagonist. Using this quaternary ammonium derivative of QNB, labelled with carbon‐11, a positron‐emitting isotope (half‐life : 20.4 minutes), the potential for quantification of myocardial muscarinic receptors in vivo using the high‐resolution, sensitive and quantitative imaging technique PET (positron emission tomography) was previously demonstrated in dogs and validated in humans. In this paper, the radiosynthesis of carbon‐11‐labelled Me‐QNB is investigated and oriented towards the preparation of multi milliCuries of radiotracer. Typically, using no‐carrier‐added [11C]methyl triflate as the alkylating agent and 0.64 mg (1.89 µmol) of QNB as precursor for labelling at 100°C for 1 minute lead to a 48.5% +/−10% (15 runs) decay‐corrected radiochemical yield (based on [11C]methyl triflate). 183 mCi (+/−39) of [11C]Me‐QNB ([11C]‐1) could be synthesized in only 27 to 28 minutes after EOB and occasionally, up to 340 mCi of [11C]Me‐QNB ([11C]‐1) were obtained, corresponding to a 85% decay‐corrected yield. The associated decay‐corrected specific radioactivities obtained were 2658 mCi/µmol (+/−971) at EOB. Copyright © 2001 John Wiley & Sons, Ltd.
Synthesis of cobalt‐55/57‐complexes for radiolabelling of platelets as a potential PET imaging agent
Authors: Schmaljohann J. , Karanikas G. , Sinzinger H.
Published: August 2002

Complexes of oxine, tropolone and mercaptopyridine‐N‐oxide (MPO) with 111In have been widely used for platelet labelling. The medium half‐life PET radioisotope cobalt‐55 would combine the higher sensitivity and resolution of PET with a half‐life allowing quantitative uptake and cell kinetic studies. We therefore investigated the synthesis and platelet uptake of 57Co‐oxine, 57Co‐tropolonate and 57Co‐MPO in vitro with cobalt‐57 as model for the cobalt‐55. The complexes were formed in high yields >90%, with the exception of 57Co‐tropolonate 38%, and were stable over several days. The platelet uptake was generally low with 5–13%. Thus, these complexes are not ideal for platelet labelling and the eventually following PET application. Copyright © 2001 John Wiley & Sons, Ltd.
Prospective stereotaxy: A novel method of trajectory alignment using real‐time image guidance
Authors: Truwit Charles L. , Liu Haiying
Published: August 2002

Purpose:

To describe prospective stereotaxy, a novel method of trajectory alignment that works in real‐time. Materials and Methods: Prospective stereotaxy was used in minimally‐invasive neurosurgical procedures in 74 patients since February 1999. This methodology differs from framed and frameless stereotaxy, both of which are based on retrospective data. Rather, prospective stereotaxy uses real‐time MR images to align a surgical trajectory.

Results:

Phantom tests and clinical procedures in all patients were successfully performed using prospective stereotaxy. In all cases, surgical targets were accessed, and the diagnostic yield of neurobiopsy using prospective stereotaxy was 100%.

Conclusion:

Prospective stereotaxy is applicable to all cross‐sectional imaging, and is particularly useful for MR‐ and CT‐guided interventions. The method is simple, reproducible, and accurate in surgical targeting for neurobiopsy and electrode placement. It does not require cumbersome stereotactic frames or expensive optical detectors, and it offers immediate entry into the field of interventional MR with cylindrical MR scanners. J. Magn. Reson. Imaging 2001;13:452–457. © 2001 Wiley‐Liss, Inc.
Electrospray and matrix‐assisted laser desorption/ionization mass spectral characterization of linear single nylon‐6 oligomers
Authors: Shan Lu , Murgasova Renata , Hercules David M. , Houalla Marwan
Published: August 2002

Synthetic nylon‐6 single molecular mass oligomers were studied by matrix‐assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI) mass spectrometry. These oligomers, considered as model compounds for the study of nylon‐6 polymers, gave good mass spectrometric results using both MALDI and ESI. In spite of the gentle nature of both techniques, the MALDI and ESI spectra showed evidence of end‐group cleavage from the oligomer chains. MALDI‐MS was found to give similar fragmentation patterns for all of the oligomer samples. An increase in doubly charged ion signals with increasing oligomer mass was observed in the ESI mass spectra, as was end‐group fragmentation. Signals from oligomer clusters were observed in ESI‐MS for the dimer, tetramer and hexamer, most likely due to non‐covalent bonding among the low‐mass oligomer molecules. Copyright © 2001 John Wiley & Sons, Ltd.
Perspectives on the use of electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry for short tandem repeat genotyping in the post‐genome era
Authors: Null Allison P. , Muddiman David C.
Published: August 2002

The recent completion of the first rough draft of the human genome has provided fundamental information regarding our genetic make‐up; however, the post‐genome era will certainly require a host of new technologies to address complex biological questions. In particular, a rapid and accurate approach to characterize genetic markers, including short tandem repeats (STRs) and single nucleotide polymorphisms (SNPs) is demanded. STRs are the most informative of the two polymorphisms owing to their remarkable variability and even dispersity throughout eukaryotic genomes. Mass spectrometry is rapidly becoming a significant method in DNA analysis and has high probability of revolutionizing the way in which scientists probe the human genome. It is our responsibility as biomolecular mass spectrometrists to understand the issues in genetic analysis and the capabilities of mass spectrometry so that we may fulfill our role in developing a rapid, reliable technology to answer specific biological questions. This perspective is intended to familiarize the mass spectrometry community with modern genomics and to report on the current state of mass spectrometry, specifically electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry, for characterization of STRs. Copyright © 2001 John Wiley & Sons, Ltd.
Simultaneous determination of etoposide and its catechol metabolite in the plasma of pediatric patients by liquid chromatography/tandem mass spectrometry
Authors: Pang Shaokun , Zheng Naiyu , Felix Carolyn A. , Scavuzzo Jennifer , Boston Ray , Blair Ian A.
Published: August 2002

The anticancer drug etoposide is associated with leukemias with MLL gene translocations and other translocations as a treatment complication. The genotype of cytochrome P450 3A4 (CYP3A4), which converts etoposide to its catechol metabolite, influences the risk. In order to perform pharmacokinetic studies aimed at further elucidation of the translocation mechanism, we have developed and validated a liquid chromatography/electrospray/tandem mass spectrometry assay for the simultaneous analysis of etoposide and its catechol metabolite in human plasma. The etoposide analog teniposide was used as the internal standard. Liquid chromatography was performed on a YMC ODS‐AQ column. Simultaneous determination of etoposide and its catechol metabolite was achieved using a small volume of plasma, so that the method is suitable for pediatric patients. The limits of detection were 200 ng ml−1 etoposide and 10 ng ml−1 catechol metabolite in human plasma and 25 ng ml−1 etoposide and 2.5 ng ml−1 catechol metabolite in protein‐free plasma, respectively. Acceptable precision and accuracy were obtained for concentrations in the calibration curve ranges 0.2–100 µg ml−1 etoposide and 10–5000 ng ml−1 catechol metabolite in human plasma. Acceptable precision and accuracy for protein‐free human plasma in the range 25–15 000 ng ml−1 etoposide and 2.5–1500 ng ml−1 etoposide catechol were also achieved. This method was selective and sensitive enough for the simultaneous quantitation of etoposide and its catechol as a total and protein‐free fraction in small plasma volumes from pediatric cancer patients receiving etoposide chemotherapy. A pharmacokinetic model has been developed for future studies in large populations. Copyright © 2001 John Wiley & Sons, Ltd.
Identification of anhydroecgonine methyl ester N‐oxide, a new metabolite of anhydroecgonine methyl ester, using electrospray mass spectrometry
Authors: Fandiño Anabel S. , Karas Michael , Toennes Stefan W. , Kauert Gerold
Published: August 2002

Cocaine is transformed into hepatotoxic metabolites through oxidative pathways. For anhydroecgonine methyl ester (AEME), the main constituent in crack smoke, the oxidative metabolism has not been studied. Therefore, incubation of AEME with rat liver microsomes was performed and a metabolite of AEME, anhydroecgonine methyl ester N‐oxide (AEMENO), was identified. The chemical structure of this new metabolite was confirmed by synthesis and by comparative interpretation of electrospray multiple‐stage mass spectra, which were obtained in the positive ion mode. This metabolite was also detected in whole blood, serum and urine samples from crack users. The application of liquid chromatography/electrospray mass spectrometry or nanoelectrospray mass spectrometry was necessary because AEMENO is susceptible to thermal degradation during gas chromatographic/mass spectrometric analysis. This study demonstrated that AEMENO is produced by rat hepatic microsomal metabolism in vitro and is present in body fluids from crack users. Copyright © 2002 John Wiley & Sons, Ltd.
Prevalence and genotypic distribution of TT virus in Athens, Greece*
Authors: Katsoulidou Antigoni , Paraskevis Dimitrios , Anastassopoulou Cleo G. , Chryssou Stella‐Eugenie , Sypsa Vassiliki , Boletis John , Malliori Meni , Karafoulidou Anastasia , Tassopoulos Nicholas C. , Hatzakis Angelos
Published: August 2002

The prevalence of TT virus (TTV) infection in various population groups from Athens, Greece, was assessed by the polymerase chain reaction (PCR) using two primer sets from distinct regions of the genome: the conventional set derived from the open reading frame‐1 (ORF‐1) and the new, highly sensitive set targeting the region that includes the TATA signal localized upstream of ORF‐2. Based on both primer sets, TTV DNA was detected in 42/50 (84.0%) healthy individuals, 42/50 (84.0%) chronic hepatitis C patients, 31/39 (79.5%) acute non‐A–E hepatitis patients (group I), 14/16 (87.5%) renal failure patients with acute non‐A–E hepatitis (group II), 47/50 (94.0%) intravenous drug users (IVDU), 36/50 (72.0%) hemophiliacs, and 21/31 (67.7%) hemodialysis patients. The presence of TTV was not associated with any particular risk group, and no differences were observed in relation to demographic, biochemical and virological characteristics between TTV DNA‐positive and ‐negative patients. TTV did not seem to have a profound effect on the course of chronic C or acute non‐A–E hepatitis either. Phylogenetic analysis revealed that TTV strains circulating in the greater metropolitan area of Athens belong not only to the G1 and G2 genotypes that are encountered worldwide, but also to G3 and to G5 that are found mainly in Europe and Asia, respectively. Further studies will shed light on the role of this highly prevalent virus. J. Med. Virol. 65:423–429, 2001. © 2001 Wiley‐Liss, Inc.