bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antibodies directed against L and D isovaline using a chemical derivatizing reagent for the measurement of their enantiomeric ratio in extraterrestrial samples: First step–production and characterization of antibodies
Authors: Vandenabeele‐Trambouze O. , Geffard M. , Bodet D. , Despois M. , Dobrijevic M. , Loustalot M‐F. Grenier , Commeyras A. 
Published: August 2002

AbstractDetermining the enantiomeric ratio of amino acids in meteorites requires very sensitive and precise measurements. In this study, an immunochemical approach, combined with new chemical derivatizing agents, was investigated for the measurement of the enantiomeric ratio of isovaline. In the initial step, L and D isovaline were derivatized with ε‐benzyloxycarbonyl‐L‐lysine‐(t‐butyl ester)‐chloroethylnitrosourea (Z‐L‐Lys‐(OtBu)‐CENU). The Z group was hydrolyzed and the resulting isovaline derivatives (L‐Lys(OtBu)‐L‐isovaline and L‐Lys(OtBu)‐D‐isovaline) were conjugated with protein using glutaraldehyde and reduced with sodium borohydride. Rabbits were immunized with the immunogenic conjugates thus obtained. Antibodies were characterized using many compounds, both derivatized and underivatized, in competitive ELISA tests. These competition experiments performed enabled us to establish the following results: 1) unconjugated L‐Lys(OtBu)‐L‐isovaline and L‐Lys(OtBu)‐D‐isovaline were poorly recognized; 2) all related L‐Lys(OtBu)‐α‐hydrogenated amino acids (L and D) were not recognized at all, which eliminates the possibility of the measurements being distorted by contamination; 3) only conjugated L‐Lys(OtBu)‐α‐amino‐isobutyric acid (AIB) was recognized by the antibody, 4) the enantiomeric discrimination of L and D isovaline through their derivatives (diastereoisomeric L‐Lys(OtBu)‐L‐isovaline and L‐Lys(OtBu)‐D‐isovaline) was in accordance with the measurement of their enantiomeric ratio. Immunopurification was shown to enhance antibody specificity. The strategy employed shows potential for the quantification of meteoritic amino acids. Chirality 14:519–526, 2002. © 2002 Wiley‐Liss, Inc.
Application of real time digital filters in NMR spectroscopy
Authors: Moskau Detlef 
Published: August 2002

AbstractSince the introduction of Fourier transform NMR spectroscopy, free induction decay (FID) has been available in a binary format, which is required to apply several mathematical treatments on the raw data. Those mathematical procedures are the application of window functions on the FID, baseline correction of the time domain data, and finally the Fourier transformation. Nevertheless, it took a long time until digital filtering was applied on NMR raw data. Digital filtering can be done as either a postprocessing procedure or on the fly. The on the fly concept is preferable, but it requires specialized and very fast processors. With the common availability of such processors, called digital signal processors (DSP), digital filtering on NMR raw data became a routine method. The application of digital filters allows us to overcome problems such as baseline distortion in the NMR spectrum due to nonperfect phase response of any common analog antialiasing filter, distortion of the signal amplitude due to a nonperfect amplitude response of any common analog antialiasing filter, a limited dynamic range due to aliased noise by nonoversampling techniques, reduced dynamic range due to quantization noise, and folded signals due to folded signals outside of the spectral window. The manner in which digital filters are used in a NMR spectrometer is the same as audio applications; it just requires stronger processors to apply high‐performance digital filters on the fly. This article is an introduction to the concept of digital filters. Therefore, the description is strongly simplified and the ideal case is assumed. © 2002 Wiley Periodicals, Inc. Concepts in Magnetic Resonance (Magn Reson Engineering) 15: 164–176, 2002
Expression of specific glycoconjugates in both primary and secondary olfactory pathways in BALB/C mice
Authors: Tisay Katarina T. , St. John James A. , Key Brian 
Published: August 2002

AbstractBinding of cell surface carbohydrates to their receptors specifically promotes axon growth and synaptogenesis in select regions of the developing nervous system. In some cases these interactions depend upon cell–cell adhesion mediated by the same glycoconjugates present on the surface of apposing cells or their processes. We have previously shown that the plant lectin Dolichos biflorus agglutinin (DBA) binds to a subpopulation of mouse primary olfactory neurons whose axons selectively fasciculate prior to terminating in the olfactory bulb. In the present study, we investigated whether these glycoconjugates were also expressed by postsynaptic olfactory neurons specifically within the olfactory pathway. We show here for the first time that DBA ligands were expressed both by a subset of primary olfactory neurons as well as by the postsynaptic mitral/tufted cells in BALB/C mice. These glycoconjugates were first detected on mitral/tufted cell axons during the early postnatal period, at a time when there is considerable synaptogenesis and synaptic remodelling in the primary olfactory cortex. This is one of the few examples of the selective expression of molecules in contiguous axon tracts in the mammalian nervous system. These results suggest that glycoconjugates recognized by DBA may have a specific role in the formation and maintenance of neural connections within a select functional pathway in the brain. J. Comp. Neurol. 443:213–225, 2002. © 2002 Wiley‐Liss, Inc.
SPACRCAN in the developing retina and pineal gland of the rat: Spatial and temporal pattern of gene expression and protein synthesis
Authors: Foletta Victoria C. , Nishiyama Kazutoshi , Rayborn Mary E. , Shadrach Karen G. , Young W. Scott , Hollyfield Joe G. 
Published: August 2002

AbstractSPACRCAN is a hyaluronan‐binding proteoglycan that is present in the pineal gland and interphotoreceptor matrix of the retina. Here, we evaluate the pattern of SPACRCAN gene expression and protein appearance during retinal and pineal gland development in the rat. In situ hybridization histochemistry with SPACRCAN riboprobes indicates that hybridization signals are first evident in the retina over developing photoreceptor cells at embryonic day 16 (E16) and in the pineal gland at E21. Immunocytochemistry using a SPACRCAN antibody shows localization of SPACRCAN protein in the developing interphotoreceptor matrix by Postnatal day 5 (P5) and in the pineal gland by P6. These studies suggest that SPACRCAN mRNA expression may occur substantially earlier than the time when SPACRCAN protein is detectable in both the retina and the pineal gland. The period of retinal histogenesis when SPACRCAN is detected first is coincident with the time photoreceptors begin to extend from the outer retinal surface, suggesting that SPACRCAN may participate in the maturation and maintenance of the light‐sensitive photoreceptor outer segment. J. Comp. Neurol. 435:354–365, 2001. © 2001 Wiley‐Liss, Inc.
Neuronal turnover in the Xenopus laevis olfactory epithelium during metamorphosis
Authors: Higgs Dennis M. , Burd Gail D. 
Published: August 2002

AbstractMetamorphic changes in the amphibian olfactory system present many interesting questions concerning the competing possibilities of neuronal respecification versus replacement. For example, are olfactory neurons retained during this transition with their presumed sensitivity to waterborne versus airborne stimuli respecified, or are olfactory neurons completely replaced? We address this question using the African clawed frog (Xenopus laevis) as a model. The water‐sensing nose (principal cavity; PC) of larval X. laevis is respecified into an air‐sensing cavity in adults, with changes in odorant receptor gene expression, ultrastructure, and site of innervation of the receptor neurons. The vomeronasal organ (VNO) does not appear to change function, structure, or innervation during metamorphosis. We labeled PC and VNO olfactory receptor neurons with injections of retrogradely transported fluorescent microspheres into the main and accessory olfactory bulbs. Injections were performed in larvae, and animals were allowed to survive through metamorphosis. After metamorphosis, few labeled cells were observed in the PC, whereas the VNO and the olfactory bulbs remained heavily labeled. Animals that were killed before metamorphosis always had extensive label in the PC epithelium regardless of how long the beads were present. This suggests that changes in the PC olfactory epithelium that are seen during metamorphosis are due primarily to turnover of the neurons in this epithelium rather than to respecification of existing neurons. These results also are discussed in terms of natural turnover time of olfactory receptor neurons. J. Comp. Neurol. 433:124–130, 2001. © 2001 Wiley‐Liss, Inc.
Regulation of neurotrophin‐induced axonal responses via Rho GTPases
Authors: Özdi̇nler P. Hande , Erzurumlu Reha S. 
Published: August 2002

AbstractNerve growth factor (NGF) and related neurotrophins induce differential axon growth patterns from embryonic sensory neurons (Lentz et al. [1999] J. Neurosci. 19:1038–1048; Ulupinar et al. [2000a] J. Comp. Neurol 425:622–630). In wholemount explant cultures of embryonic rat trigeminal ganglion and brainstem or in dissociated cell cultures of the trigeminal ganglion, exogenous supply of NGF leads to axonal elongation, whereas neurotrophin‐3 (NT‐3) treatment leads to short branching and arborization (Ulupinar et al. [2000a] J. Comp. Neurol. 425:622–630). Axonal responses to neurotrophins might be mediated via the Rho GTPases. To investigate this possibility, we prepared wholemount trigeminal pathway cultures from E15 rats. We infected the ganglia with recombinant vaccinia viruses that express GFP‐tagged dominant negative Rac, Rho, or constitutively active Rac or treated the cultures with lysophosphatitic acid (LPA) to activate Rho. We then examined axonal responses to NGF by use of the lipophilic tracer DiI. Rac activity induced longer axonal growth from the central trigeminal tract, whereas the dominant negative construct of Rac eliminated NGF‐induced axon outgrowth. Rho activity also significantly reduced, and the Rho dominant negative construct increased, axon growth from the trigeminal tract. Similar alterations in axonal responses to NT‐3 and brain‐derived neurotrophic factor were also noted. Our results demonstrate that Rho GTPases play a major role in neurotrophin‐induced axonal differentiation of embryonic trigeminal axons. J. Comp Neurol. 438:377–387, 2001. © 2001 Wiley‐Liss, Inc.
Vortex dynamics of the full time‐dependent Ginzburg‐Landau equations
Authors: Spirn Daniel 
Published: August 2002

AbstractIn the Ginzburg‐Landau model for superconductivity a large Ginzburg‐Landau parameter κ corresponds to the formation of tight, stable vortices. These vortices are located exactly where an applied magnetic field pierces the superconducting bulk, and each vortex induces a quantized supercurrent about the vortex. The energy of large‐κ solutions blows up near each vortex which brings about difficulties in analysis. Rigorous asymptotic static theory has previously established the existence of a finite number of the vortices, and these vortices are located precisely at the critical points of the renormalized energy (the free energy less the vortex self‐induction energy). A rigorous study of the full time‐dependent Ginzburg‐Landau equations under the classical Lorentz gauge is done under the asymptotic limit κ → ∞. Under slow times the vortices remain pinned to their initial configuration. Under a fast time of order κ the vortices move according to a steepest descent of the renormalized energy. © 2002 John Wiley & Sons, Inc.
A parallel Navier–Stokes solver for the rotating flow problem
Authors: da Cunha Rudnei Dias , de Bortoli Álvaro Luiz 
Published: August 2002

AbstractIn this paper, we investigate the parallel solution of rotating internal flow problems, using the Navier–Stokes equations as proposed by Speziale and Thangam (in 1983) and Speziale (in 1985). A Runge–Kutta time‐stepping scheme was applied to the equations and both sequential and message‐passing implementations were developed, the latter using MPI, and were tested on a four‐processor SGI Origin200 distributed, global shared memory parallel computer and on a 32‐processor IBM 9076 SP/2 distributed memory parallel computer. The results show that our approach to parallelize the sequential implementation requires little effort whilst providing good results even for medium‐sized problems. Copyright © 2001 John Wiley & Sons, Ltd.
The treatment of obsessive‐compulsive disorder
Authors: Haan Else de 
Published: August 2002

AbstractTreatment strategies developed and validated at academic centres are not widely used in clinical practice. One of the reasons is the fact that little attention is given to implementation problems in therapy. In this Practioner Report the treatment strategy for obsessive‐compulsive disorders is described: the treatment rationale, how to make an exposure hierarchy, ways to handle obsessions, the involvement of parents and other family members and compliance enhancement strategies. Copyright © 2001 John Wiley & Sons, Ltd.
Five‐color flow cytometric analysis of swine lymphocytes for detection of proliferation, apoptosis, viability, and phenotype
Authors: Waters W. Ray , Harkins Kristi R. , Wannemuehler Michael J. 
Published: August 2002

AbstractBackgroundThe objective of this study was to develop a method to simultaneously examine phenotype, proliferation, apoptosis, and death of antigen‐stimulated porcine lymphocytes.MethodsPeripheral blood mononuclear cells (PBMCs) were isolated from pigs vaccinated with a Brachyspira hyodysenteriae bacterin.ResultsOnce isolated, PBMCs were stained with the fluorescent membrane intercalating dye, PKH67, and cultured with or without B. hyodysenteriae whole‐cell sonicate antigen. Serial samples of nonstimulated and B. hyodysenteriae–stimulated PBMCs were harvested for flow cytometric analysis. Fluorochrome excitation was performed with spatially separated air‐cooled argon and red helium neon laser beams. Five‐color analysis included signal detection of PKH67 (proliferation), phycoerythrin (cell surface antigen), Texas Red phycoerythrin tandem (cell surface antigen), allophycocyanin (annexin V), and 7‐amino‐actinomysin D (7AAD; viability). For analysis, gates were set on live (annexin V−, 7AAD−), intact apoptotic (annexin V+, 7AADdim), and live plus intact apoptotic (annexin V+/−, 7AADdim/−) cells, and the phenotypes of PBMCs within these populations were determined during the course of the in vitro response. Dead cells (i.e., 7AADbright) were excluded from the analysis.ConclusionApplication of this method for the determination of porcine lymphocyte subset proliferation is presented. Cytometry 48:146–152, 2002. © 2002 Wiley‐Liss, Inc.
FNAB cytology of chordoma masquerading as adenocarcinoma: Case report
Authors: Chivukula Mamatha , Rao Raj , Macchi Janobya , Ghazala Farrukh , Rao R. Nagarjun , Komorowski Richard , Shidham Vinod B. 
Published: August 2002

AbstractWe report a lesion of the mobile spine in a 77‐yr‐old white male who presented with lower back pain, radiating bilaterally to the legs, with numbness on walking and standing. Magnetic resonance imaging showed a large mass within L3–L4 vertebral bodies; however, chordoma was not suspected or suggested. Fine‐needle aspiration biopsy (FNAB) of the mass revealed mostly blood with isolated flat clusters of polygonal rounded epithelial‐like cells in a myxoid background. Immunohistochemistry could not be performed on the FNAB specimen due to inadequate material for cell‐block. A limited immunocytochemistry panel was performed on one cytology smear. The tumor cells were immunoreactive for cytokeratin. During primary and expert evaluation, these features were interpreted as metastatic adenocarcinoma. Prostate and thyroid were suggested as possible primary sites. An extensive clinical and radiological search did not reveal a primary lesion. Four years later, the patient underwent surgical decompression and stabilization of his lumbar spine to avoid a catastrophic collapse of spine with neurological deficit. Histomorphological features and immunohistochemical studies at this time confirmed the lesion as chordoma. This case highlights the significance of considering chordoma in the differential diagnosis of FNAB cytology of spinal column lesions suggestive of adenocarcinoma, especially when the clusters of low‐grade epithelioid cells with vacuolated cytoplasm in a myxoid background do not show epithelial structures such as papillae, glands, or acini. Diagn. Cytopathol. 2002;26:306–309. © 2002 Wiley‐Liss, Inc.
Fine‐needle aspiration cytology of the breast: Invasive vs. in situ carcinoma
Authors: McKee Grace T. , Tambouret Rosemary H. , Finkelstein Dianne 
Published: August 2002

AbstractThe surgical management of invasive breast carcinoma differs from that of in situ disease. Invasive carcinoma necessitates axillary lymph node dissection, a procedure that has associated morbidity. We studied 80 cases (66 invasive, 14 in situ) of breast carcinoma that had a histological diagnosis and a preoperative fine‐needle aspirate. All slides were reviewed, with 17 cytologic features assessed. We found that six of these features showed a statistically significant difference between the invasive and in situ cases. These were infiltration of fat or stroma by malignant cells (72% of invasive cases demonstrated this feature, but it was not present in any of the in situ cases, P = 0.0002), the presence of myoepithelial cells overlying clusters of tumor cells (seen in 86% of in situ tumors and 7% of invasive cases, P < 0.00001), calcification (present in 71% of in situ and 15% of the invasive group, P = 0.001), foamy macrophages (noted in 64% of in situ tumors and 16% of invasive carcinomas, P = 0.0007), intracytoplasmic vacuoles (seen in 50% of invasive cases and 21% of in situ lesions, P = 0.08), and tubules (present in 30% of invasive and 7% of in situ tumors, P = 0.10). We demonstrate that invasion can be suggested in fine‐needle aspirates of carcinomas, provided that true infiltration of fibrofatty connective tissue by neoplastic cells is present. In situ disease has characteristic features, but the presence of invasion cannot be excluded, even in the presence of stromal or adipose tissue fragments without tumor infiltration. Diagn. Cytopathol. 25:73–77, 2001. © 2001 Wiley‐Liss, Inc.
Ontogenetic differences in the effects of unpaired stimulus preexposure on eyeblink conditioning in the rat*†
Authors: Rush Ashley N. , Robinette Brian L. , Stanton Mark E. 
Published: August 2002

AbstractLearned irrelevance (LIr) is a Pavlovian conditioning phenomenon in which random or unpaired preexposure to a conditional stimulus (CS) and to an unconditional stimulus (US) retards subsequent paired conditioning involving these stimuli. A previous developmental study of eyeblink conditioning in the rat suggested that LIr is not present on postnatal Day 20. Stanton, Fox, and Carter (1998) showed that unpaired preexposure to a CS and a US on postnatal Day 17 failed to retard (and, in fact, facilitated) subsequent paired conditioning involving these stimuli on postnatal Day 20. The present experiments were designed to further characterize the ontogeny of this phenomenon. In Experiment 1, LIr was observed when rat pups were tested for eyeblink conditioning as described in Stanton et al. (1998), except that preexposure occurred on postnatal Day 27, and acquisition testing occurred on postnatal Day 30. In Experiment 2, preexposure and acquisition both occurred on postnatal Day 30, and four types of preexposure were compared: chamber only, CS alone, US alone, or unpaired presentation of CS and US. Unpaired preexposure impaired acquisition relative to that of the remaining three groups, which did not differ. Experiment 3, showed that under the conditions of Experiment 2, LIr failed to appear on postnatal Day 20, but was observed on postnatal Days 25 and 30. These findings suggest that learning that events are unrelated emerges between postnatal Days 20 and 25 in the rat. Possible behavioral and neural mechanisms underlying this effect are discussed. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 39: 8–18, 2001
Anterior expression of thecaudalhomologuecCdx‐Bactivates a posterior genetic program in avian embryos
Authors: Ehrman Lisa A. , Yutzey Katherine E. 
Published: August 2002

AbstractSeveral families of regulatory genes have been implicated in anteroposterior patterning of gastrulation‐stage vertebrate embryos. Members of theDrosophila caudalfamily of homeobox genes (Cdx) are among the earliest regulators of posterior cell fates. The regulatory cascade initiated by thecaudalhomologue,cCdx‐B, was examined in avian embryos. During gastrulation,cCdx‐Bis expressed with other posterior patterning genes. In the posterior primitive streak,cCdx‐Bexpression coincides with posteriorly expressedHoxcluster genes andWntfamily members such asWnt‐8c. The hierarchical relationship between these patterning genes was examined after anterior ectopic expression of cCdx‐B. cCdx‐B expression in anterior cardiogenic cells by means of adenoviral infection leads to the induction ofWnt‐8cand the posteriorHoxgenes,Hoxa‐7,Hoxc‐6, andHoxc‐8. Cardiogenesis is not inhibited incCdx‐Bexpressing anterior lateral mesoderm, indicating that anterior cell fates are not respecified with the activation of posterior patterning genes after gastrulation. These results support an important role for cCdx‐B in initiating a posterior program of gene expression that includesWntsignaling molecules and theHoxcluster genes. © 2001 Wiley‐Liss, Inc.
p53 As a mutagen test in breast cancer
Authors: Hill Kathleen A. , Sommer Steve S. 
Published: August 2002

AbstractThe p53 gene is mutated in about half of all tumors. The p53 gene can be used as a “mutagen test,” that is, the relative frequencies of the different types of mutation can be used as an epidemiological tool to explore the contribution of exogenous mutagens vs. endogenous processes in particular cancers. p53 has been used as a mutagen test in breast cancer. Surprisingly, the pattern of p53 mutations differs among 15 geographically and ethnically diverse populations. In contrast, mutation patterns in the human factor IX gene are similar in geographically and ethnically diverse populations. Diverse p53 mutation patterns in breast cancer are consistent with a significant contribution by a diversity of exogenous mutagens. Breast tissue may be uniquely sensitive to lipophilic mutagens because of its unique architecture, characterized by tiny islands of cancer‐prone mammary epithelial cells surrounded by a sea of adipocytes. Mammary epithelial cells may be differentially susceptible to released lipophilic mutagens preferentially concentrated in adjacent adipocytes and originating in the diet. To test this hypothesis, we developed a method for measuring mutation load from ethanol‐fixed, paraffin‐embedded human tissues immunohistochemically stained with anti‐p53 antibodies. Single cells staining positively for p53 overabundance are microdissected and the gene is sequenced. It is possible to identify individuals with a high mutation load in normal breast tissue and who are presumably at increased risk for breast cancer. In addition, analysis of the p53 gene with appropriate mutation detection methodology markedly improves the prediction of early recurrence, treatment failure, and death in breast cancer patients. Mutagen tests and mutation load measurements are useful tools to identify the role of mutagens in breast cancer. Environ. Mol. Mutagen. 39:216–227, 2002. © 2002 Wiley‐Liss, Inc.