bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of the ethanol and glucose supply rate on the rate and enantioselectivity of 3‐oxo ester reduction by baker's yeast
Authors: Chin‐Joe Ifoeng , Straathof Adrie J. J. , Pronk Jack T. , Jongejan Jaap A. , Heijnen Joseph J.
Published: August 2002

Baker's‐yeast‐mediated reductions of ketones hold great potential for the industrial production of enantiopure alcohols. In this article we describe the stoichiometry and kinetics of asymmetric ketone reduction by cell suspensions of bakers’ yeast (Saccharomyces cerevisiae). A system for quantitative analysis of 3‐oxo ester reduction was developed and allowed construction of full mass and redox balances as well as determination of the influence of different process parameters on aerobic ketone reduction. The nature of the electron donor (ethanol or glucose) and its specific consumption rate by the biomass (0–1 mol.kg dw−1.h−1) affected the overall stoichiometry and rate of the process and the final enantiomeric excess of the product. Excess glucose as the electron donor, i.e. a very high consumption rate of glucose, resulted in a high rate of alcoholic fermentation, oxygen consumption, and biomass formation and therefore causing low efficiency of glucose utilization. Controlled supply of the electron donor at the highest rates applied prevented alcoholic fermentation but still resulted in biomass formation and a high oxygen requirement, while low rates resulted in a more efficient use of the electron donor. Low supply rates of ethanol resulted in biomass decrease while low supply rates of glucose provided the most efficient strategy for electron donor provision and yielded a high enantiomeric excess of ethyl (S)‐3‐hydroxybutanoate. In contrast to batchwise conversions with excess glucose as the electron donor, this strategy prevented by‐product formation and biomass increase, and resulted in a low oxygen requirement. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 29–38, 2001.
Juvenile curfews: are they an effective and constitutional means of combating juvenile violence?*
Authors: Fried Carrie S.
Published: August 2002

Curfew ordinances have become a popular way to attempt to combat juvenile crime and victimization. Although the Supreme Court has yet to hear a curfew case, several constitutional challenges have been brought in lower federal courts. The cases are replete with psychological assumptions for which there is limited empirical evidence. In applying the “strict scrutiny” standard, several courts have also questioned whether juvenile curfews are narrowly tailored to further the State's interest in reducing juvenile crime and victimization. While public opinion and reports from several police jurisdictions support the utility of juvenile curfews, recent empirical studies indicate that curfews are not effective at reducing juvenile offending or victimization. This paper argues that the emerging evidence does not support the use of juvenile curfews and urges policy makers and the courts to examine the efficacy of curfew legislation. Directions for future research that could be helpful to the courts in applying the Bellotti factors to curfew cases are also suggested. Copyright © 2001 John Wiley & Sons, Ltd.
New methods for the isolation of skeletal muscle sarcolemma and sarcoplasmic reticulum allowing a comparison between the mammalian and amphibian β2‐adrenergic receptors and calcium pumps
Authors: Hemmings Susan J.
Published: August 2002

New methods were established for the rapid and simultaneous isolation of multiple sarcolemmal and sarcoplasmic reticular fractions from very small amounts (0.25–2.0 g) of skeletal muscle. Theβ2‐adrenergic receptor and calcium transport systems were used as indices of purity and functional integrity as well as being the focal points of the study. These methods were found to be suitable for the special needs of small tissue samples, allowed rapid preparation and were appropriate for skeletal muscle from various species, frogs to mammals. The sarcolemmalβ2‐adrenergic receptor was expressed in frogs and mammals at similar levels of expression (336–454 fmol·mg−1). The calcium pump was also present in sarcolemmal and sarcoplasmic reticular fractions in all species but notable species differences were found. In sarcolemmal fractions, while calcium binding was uniformly low (<1 nmol·mg−1), oxalate stimulation was variable: low in frogs (∼1.05‐fold) high in mammals (120–450‐fold). In sarcoplasmic reticular fractions, calcium binding was low in frogs (4–9 nmol·mg−1) and much higher in mammals (322–383 nmol·mg−1); oxalate stimulated calcium transport to a much greater extent in frogs (<70‐fold) than in mammals (1.6–2‐fold). It is concluded that theβ2‐adrenergic receptor appears to be strongly conserved in skeletal muscle while the use of calcium pumps evolves from reliance in Amphibia on the sarcoplasmic reticular calcium pump to the use in Mammalia of calcium pumps from both the sarcoplasmic reticulum and the plasma membrane. Copyright © 2001 John Wiley & Sons, Ltd.
Stent implantation for superior vena cava occlusion after the mustard operation
Authors: Mohsen Aly El , Rosenthal Eric , Qureshi Shakeel A. , Tynan Michael
Published: August 2002

A 25‐year‐old man who had undergone a Mustard repair for complete transposition of the great arteries 21 years previously developed complete occlusion of the superior vena cava and obstruction of the inferior vena cava. Transcatheter recanalization was performed using needle puncture of the superior obstruction followed by stent implantation into both systemic venous pathways with relief of obstructive symptoms. Cathet Cardiovasc Intervent 2001;52:351–354. © 2001 Wiley‐Liss, Inc.
Yb(fod)3 in the spectroscopic determination of the configuration of chiral diols: A survey of the lanthanide diketonate method
Authors: Di Bari Lorenzo , Lelli Moreno , Pintacuda Guido , Salvadori Piero
Published: August 2002

A modification of the diketonate method for the determination of the absolute configuration of chiral vicinal diols, first proposed by Nakanishi, is taken under object and tested with a set of aliphatic and aromatic substrates; Yb(fod)3 (fod = 6,6,7,7,8,8,8‐heptafluoro‐2,2‐dimethyl‐3,5‐octanedionate) is employed as the chromophoric species. The replacement of dpm (dpm = dipivalomethanate) with fod ensures the formation of strong and stable signals in the UV region, whose signs are related to the configuration of the chelating molecule. The choice of ytterbium as the central cation introduces two major advantages: the electronic f–f transition of the rare‐earth supplies a second spectral window in the near‐IR, which is sensitive to the chemical environment around the atom. This allowed us to ascertain the number of different species present in solution and the observation of an induced CD also for strongly UV‐absorbing substrates. The pseudocontact shifts induced in the 1H‐NMR spectrum by the unpaired electron of the lanthanide ion provide valuable structural information on the adducts. Chirality 14:265–273, 2002. © 2002 Wiley‐Liss, Inc.
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

Determining 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

Since 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

Binding 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

SPACRCAN 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

Metamorphic 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

Nerve 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

In 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

In 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

Treatment 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

Background

The objective of this study was to develop a method to simultaneously examine phenotype, proliferation, apoptosis, and death of antigen‐stimulated porcine lymphocytes.

Methods

Peripheral blood mononuclear cells (PBMCs) were isolated from pigs vaccinated with a Brachyspira hyodysenteriae bacterin.

Results

Once 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.

Conclusion

Application 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

We 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

The 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

Learned 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

Several 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

The 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.
Why is DNA damage signaling so complicated? Chaos and molecular signaling
Authors: Yarosh Daniel B.
Published: August 2002

Molecular signaling in eukaryotic cells is accomplished by complex and redundant pathways converging on key molecules that are allosterically controlled by a limited number of signaling proteins. The p53‐signaling pathway is an example of a complicated sequence of signals produced in response to DNA damage. This pattern of signaling may arise from chance occurrences at the origin of life and the necessities imposed on a nanomolar system. From this viewpoint, chaos theory may explain the origin, complexity, and convergence of these pathways. Environ. Mol. Mutagen. 38:132–134, 2001 © 2001 Wiley‐Liss, Inc.
Multivariate data analysis of fluorescence signals from biological aerosols
Authors: Tjärnhage Torbjörn , Strömqvist Marianne , Olofsson Göran , Squirrell David , Burke James , Ho Jim , Spence Mel
Published: August 2002

This paper describes the use of multivariate data analysis of multiwavelength fluorescence measurements of biological aerosols collected by an air to liquid cyclone sampler. The enriched aerosol suspension was analyzed in a flow cell by a commercial spectrofluorometer at eight different wavelength combinations. The data were obtained from the disseminations of biological simulants at the 6th Joint Field Trials at Defence Research Establishment Suffield, Ralston, Alberta, Canada. The measurement concept was to use intrinsic biological fluorescence to distinguish between the different simulants as well as to distinguish them from interfering particles such as smoke and dust. Fluorescence data were analyzed using principal component analysis. © 2001 John Wiley & Sons, Inc. Field Analyt Chem Technol 5: 171–176, 2001
Performance of algebraic multi‐grid solvers based on unsmoothed and smoothed aggregation schemes
Authors: Webster R.
Published: August 2002

A comparison is made of the performance of two algebraic multi‐grid (AMG0 and AMG1) solvers for the solution of discrete, coupled, elliptic field problems. In AMG0, the basis functions for each coarse grid/level approximation (CGA) are obtained directly by unsmoothed aggregation, an appropriate scaling being applied to each CGA to improve consistency. In AMG1 they are assembled using a smoothed aggregation with a constrained energy optimization method providing the smoothing. Although more costly, smoothed basis functions provide a better (more consistent) CGA. Thus, AMG1 might be viewed as a benchmark for the assessment of the simpler AMG0. Selected test problems for D'Arcy flow in pipe networks, Fick diffusion, plane strain elasticity and Navier–Stokes flow (in a Stokes approximation) are used in making the comparison. They are discretized on the basis of both structured and unstructured finite element meshes. The range of discrete equation sets covers both symmetric positive definite systems and systems that may be non‐symmetric and/or indefinite. Both global and local mesh refinements to at least one order of resolving power are examined. Some of these include anisotropic refinements involving elements of large aspect ratio; in some hydrodynamics cases, the anisotropy is extreme, with aspect ratios exceeding two orders. As expected, AMG1 delivers typical multi‐grid convergence rates, which for all practical purposes are independent of mesh bandwidth. AMG0 rates are slower. They may also be more discernibly mesh‐dependent. However, for the range of mesh bandwidths examined, the overall cost effectiveness of the two solvers is remarkably similar when a full convergence to machine accuracy is demanded. Thus, the shorter solution times for AMG1 do not necessarily compensate for the extra time required for its costly grid generation. This depends on the severity of the problem and the demanded level of convergence. For problems requiring few iterations, where grid generation costs represent a significant penalty, AMG0 has the advantage. For problems requiring a large investment in iterations, AMG1 has the edge. However, for the toughest problems addressed (vector and coupled vector–scalar fields discretized exclusively using finite elements of extreme aspect ratio) AMG1 is more robust: AMG0 has failed on some of these tests. However, but for this deficiency AMG0 would be the preferred linear approximation solver for Navier–Stokes solution algorithms in view of its much lower grid generation costs. Copyright © 2001 John Wiley & Sons, Ltd.
A numerical study of an unsteady laminar flow in a doubly constricted 3D vessel
Authors: Rathish Kumar B. V. , Yamaguchi T. , Liu H. , Himeno R.
Published: August 2002

Unsteady flow dynamics in doubly constricted 3D vessels have been investigated under pulsatile flow conditions for a full cycle of period T. The coupled non‐linear partial differential equations governing the mass and momentum of a viscous incompressible fluid has been numerically analyzed by a time accurate Finite Volume Scheme in an implicit Euler time marching setting. Roe's flux difference splitting of non‐linear terms and the pseudo‐compressibility technique employed in the current numerical scheme makes it robust both in space and time. Computational experiments are carried out to assess the influence of Reynolds' number and the spacing between two mild constrictions on the pressure drop across the constrictions. The study reveals that the pressure drop across a series of mild constrictions can get physiologically critical and is also found to be sensitive both to the spacing between the constrictions and the oscillatory nature of the inflow profile. The flow separation zone on the downstream constriction is seen to detach from the diverging wall of the constriction leading to vortex shedding with 3D features earlier than that on the wall in the spacing between the two constrictions. Copyright © 2002 John Wiley & Sons, Ltd.
Ectopic sequences from truncated HMGIC in liposarcomas are derived from various amplified chromosomal regions
Authors: Meza‐Zepeda Leonardo A. , Berner Jeanne‐Marie , Henriksen Jørn , South Andrew P. , Pedeutour Florence , Dahlberg Anine B. , Godager Linda H. , Nižetić Dean , Forus Anne , Myklebost Ola
Published: August 2002

The HMGIC gene codes for an architectural transcription factor frequently rearranged by translocation in lipomas and other benign mesenchymal tumors. In sarcomas, malignant tumors of mesenchymal origin, the gene is also found to be rearranged, but in addition amplified and overexpressed. Here we report the sequence, chromosomal localization, and expression patterns of 11 novel ectopic sequences fused to exons 2 and 3 of HMGIC in seven different sarcoma samples. In addition, we identified a number of variant transcripts observed previously in benign tumors. Consistent with the suggested role of HMGIC in adipocytic differentiation, most of the novel ectopic sequences were observed in well‐differentiated liposarcomas. These tumors are known to have complex marker chromosomes containing amplified segments from several chromosomes. Five novel sequences were derived from 12q14–q15, where HMGIC resides, two from 1q24, a region frequently amplified in these types of tumors, two from 11q14, and one from chromosome 2. All except one of the aberrant transcripts encoded truncated proteins with intact DNA‐binding domains (AT hooks) but lacking the C‐terminal acidic region, a target for constitutive phosphorylation by protein kinase CK2. Some of the ectopic sequences were transcribed in other tissues, and most of the ectopic sequences also showed recurrent amplification in liposarcomas. © 2001 Wiley‐Liss, Inc.
Unusual case of leukemic mantle cell lymphoma with amplified CCND1/IGH fusion gene
Authors: Gruszka‐Westwood Alicja M. , Atkinson Shayne , Summersgill Brenda M. , Shipley Janet , Elnenaei Manal O. , Jain Paresh , Hamoudi Rifat A. , Kaeda Jaspal S. , Wotherspoon Andrew C. , Matutes Estella , Catovsky Daniel
Published: August 2002

We describe a case of leukemic mantle cell lymphoma (MCL) with complex karyotype and amplification of the CCND1/IGH fusion gene. Testing for the presence of t(11;14), the hallmark of MCL, revealed multiple copies of the fusion signals. We therefore conducted extensive molecular cytogenetic studies to delineate the nature and consequences of such an abnormality. We localized the amplification to the der(14)t(11;14) and to a der(2) chromosome in a form of interspersed chromosome 11 and 14 material. This resulted in high expression of cyclin D1 mRNA and the protein expressed independently of the cell cycle phase. CGH analysis revealed that the overrepresentation on chromosome 11 included chromosomal band 11q23 in addition to the CCND1 locus at 11q13. The band 11q23 harbors the ataxia telangiectasia mutated (ATM) gene recently proposed to be involved in the pathogenesis of MCL with high incidence of deletions in this locus. Using YAC 801e11, containing the ATM gene, we demonstrated several hybridization signals, suggesting that this region also formed part of the amplicon. This case also showed TP53 gene abnormalities: protein expression, monoallelic deletion, and a mutation in exon 5. The clinical course was aggressive, and the patient died within 6 months of presentation. This is to our knowledge the first description of amplification of the CCND1/IGH fusion gene in a human neoplasm, which may have played a role in the fulminating course of the disease in this patient. © 2002 Wiley‐Liss, Inc.
Soil management in pre‐Hispanic raised field systems: Micromorphological evidence from Hacienda Zuleta, Ecuador
Authors: Wilson Clare , Simpson Ian A. , Currie Elizabeth J.
Published: August 2002

Soils‐based evidence derived from thin section micromorphology is used to explore contrasts in pre‐Hispanic and Hispanic arable land management practices associated with raised fields in an inter‐Andean valley of Ecuador. Differences in textural pedofeature characteristics suggest that, where they are found in the same locality, camellón systems were more intensively manured and cultivated than wachu systems. Both, however, were more intensively managed than traditional Hispanic arable fields. The importance of the camellón in pre‐Hispanic agriculture is emphasized by soils‐based evidence that highlights the efforts made to clear these fields of volcanic ash after the Quilotoa eruption of ca. A.D. 1280. This research suggests that, in an andosol context, pre‐Hispanic and Hispanic arable land management practices leave relict and fossil soil micromorphology features that can be used to interpret land use intensities. © 2002 Wiley Periodicals, Inc.
An enhancer sequence directs LacZ expression to developing pharyngeal endoderm in transgenic mice
Authors: Parmar Hema , Coletta P. Louise , Faruque Nadeem , Sharpe Paul T.
Published: August 2002

Summary: The murine Hoxc‐6 homeobox gene comprises three exons with two distinct promoters (PRI and PRII) located 9 kb apart. To characterise the PRII promoter, a region 3 kb upstream of the transcription start site was sequenced, and an Antananapedia‐like consensus binding sequence was found (Coletta et al., 1991). A LacZ reporter gene construct, containing three copies of this sequence, directs highly specific expression in cells forming pharyngeal endoderm in transgenic mice. Expression was first detected in a few individual anterior endoderm cells at E7.5, which increase in number up to E9.5, where expression was clearly visible in the pharyngeal endoderm. Expression of the endodermal genes HNF3β, Pax‐9, Shh, and Nkx2.5 showed colocalization with the LacZ‐positive cells in the foregut and pharyngeal endoderm. This novel enhancer provides a means of tracking the morphogenetic movement of endodermal cells fated to form the foregut. genesis 31:57–63, 2001. © 2001 Wiley‐Liss, Inc.
Genome‐wide linkage analyses of total serum IgE using variance components analysis in asthmatic families
Authors: Mathias R.A. , Freidhoff L.R. , Blumenthal M.N. , Meyers D.A. , Lester L. , King R. , Xu J.F. , Solway J. , Barnes K.C. , Pierce J. , Stine O.C. , Togias A. , Oetting W. , Marshik P.L. , Hetmanski J.B. , Huang S.K. , Ehrlich E. , Dunston G.M. , Malveaux F. , Banks‐Schlegel S. , Cox N.J. , Bleecker E. , Ober C. , Beaty T.H. , Rich S.S.
Published: August 2002

Variance components models were used to analyze total IgE levels in families ascertained though the Collaborative Study of the Genetics of Asthma (CSGA) using a genome‐wide array of polymorphic markers. While IgE levels are known to be associated with clinical asthma and recognized to be under strong genetic control (here the heritability was estimated at 44–60% in the three racial groups), specific genes influencing this trait are still largely unknown. Multipoint analysis of 323 markers yielded little indication of specific regions containing a trait locus controlling total serum IgE levels (adjusted for age and gender). Although a number of regions showed LOD statistics above 1.5 in Caucasian families (chromosome 4) and in African‐American families (chromosomes 2 and 4), none yielded consistent evidence in all three racial groups. Analysis of total IgE adjusted for gender, age and Allergy Index (a quantitative score of skin test sensitivity to 14 common aeroallergens) was conducted on these data. In this analysis, a much stronger signal for a trait locus controlling adjusted log[total IgE] was seen on the telomeric end of chromosome 18, but only in Caucasian families. This region accounted for most of the genetic variation in log[total IgE], and may represent a quantitative trait locus for IgE levels independent of atopic response. Oligogenic analysis accounting simultaneously for the contribution of this locus on chromosome 18 and other chromosomal regions showing some evidence of linkage in these Caucasian families (on chromosomes 2, 4 and 20) failed to yield significant evidence for interaction. Genet. Epidemiol. 20:340–355, 2001. © 2001 Wiley‐Liss, Inc.
New approach to localize speech relevant brain areas and hemispheric dominance using spatially filtered magnetoencephalography
Authors: Kober Helmut , Möller Martin , Nimsky Christopher , Vieth Jürgen , Fahlbusch Rudolf , Ganslandt Oliver
Published: August 2002

We used a current localization by spatial filtering‐technique to determine primary language areas with magnetoencephalography (MEG) using a silent reading and a silent naming task. In all cases we could localize the sensory speech area (Wernicke) in the posterior part of the left superior temporal gyrus (Brodmann area 22) and the motor speech area (Broca) in the left inferior frontal gyrus (Brodmann area 44). Left hemispheric speech dominance was determined in all cases by a laterality index comparing the current source strength of the activated left side speech areas to their right side homologous. In 12 cases we found early Wernicke and later Broca activation corresponding to the Wernicke‐Geschwind model. In three cases, however, we also found early Broca activation indicating that speech‐related brain areas need not necessarily be activated sequentially but can also be activated simultaneously. Magnetoencephalography can be a potent tool for functional mapping of speech‐related brain areas in individuals, investigating the time‐course of brain activation, and identifying the speech dominant hemisphere. This may have implications for presurgical planning in epilepsy and brain tumor patients. Hum. Brain Mapping 14:236–250, 2001. © 2001 Wiley‐Liss, Inc.
Synthesis and properties of 4,5‐dihydrobenzo[e]imidazo[2,1‐c][1,4,2]diazaphosphinine derivatives
Authors: Ivanov Vladimir V. , Yurchenko Alexandr A. , Chernega Alexander N. , Pinchuk Alexandr M. , Tolmachev Andrej A.
Published: August 2002

A number of 4,5‐dihydrobenzo[e]imidazo[2,1‐c][1,4,2]diazaphosphinine derivatives were prepared by the direct phosphorylation of 1‐(4‐Chlorophenylcarboxamido)‐2‐(1H‐1‐imidazolyl)‐5‐trifluoromethylbenzene in basic medium with phosphorus(III) bromide and dibromophenylphosphine. The tricyclic compounds 6a, 6b, and 9 having a trivalent phosphorus atom undergo the diazaphosphinine ring opening upon treatment with secondary amines in the presence of sulfur. © 2002 John Wiley & Sons, Inc. Heteroatom Chem 13:84–92, 2002; DOI 10.1002/hc.10000
SRN1 reaction of haloarenes with benzenethiolate, benzeneselenolate, and benzenetellurolate ions promoted by SmI2
Authors: Zhang Yongmin , Guo Hongyun
Published: August 2002

SRN1 reaction is of haloarenes with benzenethiolate, benzeneselenate, and benzenetellurolate ions can be carried out by use of samarium diiodide (SmI2) as a promoter in DMF‐THF to afford the corresponding ArZPh compounds in moderate to good yields. © 2001 John Wiley & Sons, Inc. Heteroatom Chem 12:539–541, 2001