bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractStabilization 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

AbstractElucidating 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

AbstractA 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

AbstractIt 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

AbstractUp 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

AbstractThe 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

AbstractHere, 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

AbstractCytosolic 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

AbstractWe 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

AbstractWe 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

AbstractOrganotypic 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

AbstractThe 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

AbstractDuring 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

AbstractJuvenile 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

Abstract(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

AbstractMe‐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

AbstractComplexes 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

AbstractPurpose: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

AbstractSynthetic 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.