bluuebunny/crossref_metadata_2025 huggingface dataset:
CD8+-Cell-Mediated Suppression of Virulent Simian Immunodeficiency Virus during Tenofovir Treatment
Authors: Van Rompay Koen K. A. , Singh Raman P. , Pahar Bapi , Sodora Donald L. , Wingfield Casey , Lawson Jonathan R. , Marthas Marta L. , Bischofberger Norbert
Published: April 2004

The ability of tenofovir to suppress viremia in simian immunodeficiency virus (SIV)-infected macaques for years despite the presence of virulent viral mutants with reduced in vitro susceptibility is unprecedented in this animal model. In vivo cell depletion experiments demonstrate that tenofovir's ability to suppress viremia during acute and chronic infection is significantly dependent on the presence of CD8+lymphocytes. Continuous tenofovir treatment was required to maintain low viremia. Although it is unclear whether this immune-mediated suppression of viremia is linked to tenofovir's direct antiviral efficacy or is due to independent immunomodulatory effects, these studies prove the concept that antiviral immune responses can play a crucial role in suppressing viremia during anti-human immunodeficiency virus drug therapy.
The Herpes Simplex Virus Type 1 UL20 Protein Modulates Membrane Fusion Events during Cytoplasmic Virion Morphogenesis and Virus-Induced Cell Fusion
Authors: Foster Timothy P. , Melancon Jeffrey M. , Baines Joel D. , Kousoulas Konstantin G.
Published: April 2004

The herpes simplex virus type 1 (HSV-1) UL20 protein is an important determinant for virion morphogenesis and virus-induced cell fusion. A precise deletion of the UL20 gene in the HSV-1 KOS strain was constructed without affecting the adjacent UL20.5 gene. The resultant KOS/UL20-null virus produced small plaques of 8 to 15 cells in Vero cells while it produced wild-type plaques on the complementing cell line G5. Electron microscopic examination of infected cells revealed that the KOS/UL20-null virions predominantly accumulated capsids in the cytoplasm while a small percentage of virions were found as enveloped virions within cytoplasmic vacuoles. Recently, it was shown that UL20 expression was necessary and sufficient for cell surface expression of gK (T. P. Foster, X. Alvarez, and K. G. Kousoulas, J. Virol. 77:499-510, 2003). Therefore, we investigated the effect of UL20 on virus-induced cell fusion caused by syncytial mutations in gB and gK by constructing recombinant viruses containing the gBsyn3 or gKsyn1 mutations in a UL20-null genetic background. Both recombinant viruses failed to cause virus-induced cell fusion in Vero cells while they readily caused fusion of UL20-null complementing G5 cells. Ultrastructural examination of UL20-null viruses carrying the gBsyn3 or gKsyn1 mutation revealed a similar distribution of virions as the KOS/UL20-null virus. However, cytoplasmic vacuoles contained aberrant virions having multiple capsids within a single envelope. These multicapsid virions may have been formed either by fusion of viral envelopes or by the concurrent reenvelopment of multiple capsids. These results suggest that the UL20 protein regulates membrane fusion phenomena involved in virion morphogenesis and virus-induced cell fusion.
Human Immunodeficiency Virus Type 1 Envelope Glycoproteins That Lack Cytoplasmic Domain Cysteines: Impact on Association with Membrane Lipid Rafts and Incorporation onto Budding Virus Particles
Authors: Bhattacharya Jayanta , Peters Paul J. , Clapham Paul R.
Published: April 2004

The human immunodeficiency virus type 1 (HIV-1) envelope comprises a surface gp120 and a transmembrane gp41. The cytoplasmic domain of gp41 contains cysteine residues (C764 and C837) which are targets for palmitoylation and were reported to be required for envelope association with lipid rafts and assembly on budding virions (I. Rousso, M. B. Mixon, B. K. Chen, and P. S. Kim, Proc. Natl. Acad. Sci. USA97:13523-13525, 2000). Several infectious HIV-1 clones contain envelopes that have no gp41 cytoplasmic cysteines. Since no other gp41 amino acid is a target for palmitoylation, these clones imply that palmitoylation is not essential for envelope trafficking and assembly. Here, we show that HIV-1 envelope mutants that lack gp41 cytoplasmic cysteines are excluded from light lipid rafts. Envelopes that contained residues with bulky hydrophobic side chains instead of cysteines retained their association with heavy rafts and were nearly fully functional for incorporation into virions and infectivity. Substitution of cysteines with alanines or serines eliminated raft association and more severely reduced envelope incorporation onto virions and their infectivity. Nevertheless, the A764/A837 mutant envelope retained nearly 40% infectivity compared to the wild type, even though this envelope was excluded from lipid rafts. Our results demonstrate that gp41 cytoplasmic cysteines that are targets for palmitoylation and are required for envelope trafficking to classical lipid rafts are not essential for HIV-1 replication.
Classical Swine Fever Virus Glycoprotein E
rns
Is an Endoribonuclease with an Unusual Base Specificity
Authors: Hausmann Yvonne , Roman-Sosa Gleyder , Thiel Heinz-Jürgen , Rümenapf Till
Published: April 2004

The glycoprotein E
rns
of pestiviruses is a virion-associated and -secreted RNase that is involved in virulence. The requirements at the cleavage site in heteropolymeric RNA substrates were studied for E
rns
. Limited digestion of heteropolymeric RNA substrates indicated a cleavage 5′ of uridine residues irrespective of the preceding nucleotide (Np/U). To further study specificity radiolabeled RNA, molecules of 45 to 56 nucleotides in length were synthesized that contained no or a single Np/U cleavage site. Cleavage was only observed in substrates containing an ApU, CpU, GpU, or UpU dinucleotide and occurred in two steps, an initial NpU-specific and a consecutive unspecific degradation. The NpU-specific cleavage was resistant to 7 M urea while the second-order cleavage was sensitive to denaturation. Kinetic analyses revealed that E
rns
is a highly active endoribonuclease (k
cat
/

K
m

= 2 × 10
6
to 10 × 10
6
M
−1
s
−1
) with a strong affinity to NpU containing single-stranded RNA substrates (

K
m

= 85 to 260 nM).
The Development of the P.E.T.Scale for the Measurement of Physical and Emotional Tormenting Against Animals in Adolescents
Authors: Baldry Anna
Published: April 2004

The Physical and Emotional Tormenting Against Animals Scale (P.E.T.) is a new self-administered scale to measure physical and emotional abuse against animals among adolescents. This study is a first attempt to establish the reliability and validity of this newly developed scale with a non-clinical sample of 1396 Italian adolescents, aged 11-17 years.The scale measures different dimensions of animal abuse, ranging from mild to more severe: bothering, tormenting, hitting, harming, and being cruel to an animal. The scale measures the prevalence and frequency of directed and witnessed abuse against animals. Principal components analysis suggested a two factor solution, with factors labeled "direct" and "indirect" animal abuse; internal consistency was good for each factor.The direct animal abuse factor was significantly correlated with the Child Behavior Checklist's single item assessing engagement in cruelty against animals. These findings suggest that the PET scale has potential as an instrument for the measurement of animal abuse. Future studies of the PET scale's psychometric properties, and cross-validation on new populations, are needed.
Teachers’ personal practical knowledge and interactive decisions
Authors: Tsang Wai King
Published: April 2004

This case study aims to investigate the role of teachers’ personal practical knowledge in interactive decision making for three pre-ser-vice non-native ESL teachers. The research question is: What role does pre-service ESL teachers’ personal practical knowledge (operationalized as teaching maxims in this study) play in their interactive decisions (decisions made during teaching)? Content analysis on language learning =teaching autobiographies was carried out to map out teachers’ personal practical knowledge. Interviews, observation over time, and a video-based method of eliciting introspective data were employed. The teachers’ lesson plans and journals were triangulated with the other data. Findings were that some parts of a teacher’s personal practical knowledge might be competitive or conditional while being applied in particular instructional contexts and that while some new maxims start shaping during classroom teaching, some old ones are seen in a new light. Results also show that during classroom teaching, the participants have limited access to their personal practical knowledge (only about half of the interactive decisions made were guided by their personal practical knowledge). However, this played a part in informing post-active decisions (decisions made after teaching), and delayed accessibility to such knowledge nonetheless helped evaluate new maxims of teaching.
Dopamine Transmission in the Human Striatum during Monetary Reward Tasks
Authors: Zald David H. , Boileau Isabelle , El-Dearedy Wael , Gunn Roger , McGlone Francis , Dichter Gabriel S. , Dagher Alain
Published: April 2004

Previous studies have demonstrated the ability of the [11C]raclopride positron emission tomography (PET) technique to measure behaviorally induced changes in endogenous dopamine transmission in humans. However, these studies have lacked well matched sensorimotor control conditions, making it difficult to know what sensory, cognitive, or motor features contributed to changes in dopaminergic activity. Here we report on [11C]raclopride PET studies in which healthy humans performed card selection tasks for monetary rewards. During separate scans, subjects completed a variable ratio (VR) reward schedule with a 25% reward rate in which they did not know the outcome of their responses in advance, a fixed ratio (FR) 25% reward schedule in which outcomes were fully predictable, and a sensorimotor control (SC) condition involving similar sensory and motor demands but no rewards. Relative to the SC condition, the FR schedule produced only modest increases in dopamine transmission and no decreases relative to the SC condition. In contrast, the VR schedule produced significant increases in dopamine transmission in the left medial caudate nucleus while simultaneously producing significant decreases in other areas of the caudate and putamen. These data indicate: (1) the feasibility of measuring alterations in dopamine transmission even after controlling for sensorimotor features and (2) the complex and regionally specific influence of VR schedules on dopamine transmission. The implications of these results are discussed in relation to conflicting models of dopaminergic functioning arising from studies using electrophysiological and microdialysis techniques in animals.
Variations in Nucleus Accumbens Dopamine Associated with Individual Differences in Maternal Behavior in the Rat
Authors: Champagne Frances A. , Chretien Pablo , Stevenson Carl W. , Zhang Tie Yuan , Gratton Alain , Meaney Michael J.
Published: April 2004

Lactating rats exhibit stable individual differences in pup licking/grooming. We usedin vivovoltammetry to monitor changes in extracellular dopamine (DA) in the nucleus accumbens (n. Acc) shell of lactating rats interacting with pups and found that (1) the DA signal increased significantly with pup licking/grooming; (2) the onset of such increases preceded pup licking/grooming; and (3) the magnitude and duration of the increase in the DA signal were significantly correlated with the duration of the licking/grooming bout. In females characterized on the basis of behavioral observations as high-licking/grooming mothers, the magnitude of the increase in the DA signal associated with licking/grooming was significantly greater than in low-licking/grooming dams. Dopamine transporter binding in the n. Acc was increased in low-compared with high-licking/grooming mothers. Injection of the selective DA uptake inhibitor GBR 12909 [1-(2-(Bis-(4-fluorophenyl)methoxy)ethyl)-4-(3 phenypropyl)piperazine dihydrochloride] (5 mg/kg, s.c.) increased the DA signal in the n. Acc and pup licking/grooming in low-licking/grooming mothers to levels comparable with those observed in high-licking/grooming dams. Receptor autoradiographic studies showed elevated levels of D1and D3receptors in the n. Acc shell region in high-licking/grooming dams. These results suggest that high- and low-licking/grooming dams differ in mesolimbic dopaminergic activity associated with mother-pup interactions. Such differences may serve as neural substrates for individual differences in the motivational component of maternal behavior.
Austenitic Stainless Steels from Quantum Mechanical Calculations
Authors: Vitos L. , Korzhavyi P.A. , Johansson B.
Published: April 2004

Quantum mechanics is used to study the influence of the chemical composition on the elastic properties of austenitic stainless steels. Fe based alloys comprising approximately 15% Cr and 8% Ni are predicted to have the largest hardness among the usual austenitic steels, which, however, is associated with increased brittleness and susceptibility to various forms of localized corrosion. It is shown that few percent of additional Os or Ir to Fe15Cr8Ni alloy significantly improve on both of these shortcomings, without deteriorating the hardness.
Superparamagnetic Silica‐Iron Oxide Nanocomposites for Application in Hyperthermia
Authors: Chastellain M. , Petri A. , Gupta A. , Rao K.V. , Hofmann H.
Published: April 2004

Superparamagnetic iron oxide particles embedded in silica are studied for application in hyperthermia. The temperature increase is studied when submitting the samples to a weak alternating magnetic field. The influence of the iron oxide size distribution, saturation magnetization, out of phase susceptibility and anisotropy constant is discussed. A theoretical calculation of power loss is carried out and agrees with experimental data.
Momentaufnahmen photoangeregter Moleküle in fehlgeordneten Medien mit gepulster Synchrotron‐Röntgenstrahlung
Authors: Chen Lin X.
Published: April 2004

An jeder photochemischen Reaktion sind photoangeregte Moleküle beteiligt. Die Kenntnis ihrer Strukturen in fehlgeordneten Medien, in denen die meisten photochemischen Reaktionen ablaufen, ist Voraussetzung für das Verständnis der Photochemie. Über diese Strukturen war lange aber nur wenig bekannt, weil geeignete Röntgenquellen fehlten. Dank der heute verfügbaren gepulsten Röntgenquellen können die Strukturen von Molekülen in kurzlebigen angeregten Zuständen in fehlgeordneten Medien mit Laserpump‐Röntgenanalyse‐Techniken in Synchrotrons der dritten Generation mit Zeitauflösungen von 30–100 ps untersucht werden. Diese Studien liefern wertvolle Informationen über die strukturellen Ursachen molekularer Eigenschaften in angeregten Zuständen. Mit derzeit in Bau befindlichen Röntgeneinrichtungen könnte die Zeitauflösung bei der Strukturbestimmung angeregter Zustände sogar in den Femtosekundenbereich gedrückt werden. Damit wären “molekulare Filme” von Bindungsbrüchen und ‐bildungen oder der Schwingungsrelaxation möglich.
Nanolithography and Nanochemistry: Probe‐Related Patterning Techniques and Chemical Modification for Nanometer‐Sized Devices
Authors: Wouters Daan , Schubert Ulrich S.
Published: April 2004

The size regime for devices produced by photolithographic techniques is limited. Therefore, other patterning techniques have been intensively studied to create smaller structures. Scanning‐probe‐based patterning techniques, such as dip‐pen lithography, local force‐induced patterning, and local‐probe oxidation‐based techniques are highly promising because of their relative ease and widespread availability. The latter of these is especially interesting because of the possibility of producing nanopatterns for a broad range of chemical and physical modification and functionalization processes; both the production of nanometer‐sized electronic devices and the formation of devices involving (bio)molecular recognition and sensor applications is possible. This Review highlights the development of various scanning probe systems and the possibilities of local oxidation methods, as well as giving an overview of state‐of‐the‐art nanometer‐sized devices, and a view of future development.
Cover Picture: A Droplet‐Based, Composite PDMS/Glass Capillary Microfluidic System for Evaluating Protein Crystallization Conditions by Microbatch and Vapor‐Diffusion Methods with On‐Chip X‐Ray Diffraction (Angew. Chem. Int. Ed. 19/2004)
Authors: Zheng Bo , Tice Joshua D. , Roach L. Spencer , Ismagilov Rustem F.
Published: April 2004

Protein crystals can be grown inside nanoliter droplets in a composite polydimethylsiloxane/glass microfluidic device. R. F. Ismagilov and co‐workers describe in their Communication on page 2508 ff. how this approach can be used to screen conditions for protein crystallization by both microbatch and vapor‐diffusion methods. The quality of the crystals grown in the device was evaluated directly from the X‐ray diffraction pattern shown in the background.
Effect of processing method on surface and weathering characteristics of wood–flour/HDPE composites
Authors: Stark Nicole M. , Matuana Laurent M. , Clemons Craig M.
Published: April 2004

Wood–plastic lumber is promoted as a low‐maintenance high‐durability product. When exposed to accelerated weathering, however, wood–plastic composites may experience a color change and/or loss in mechanical properties. Different methods of manufacturing wood–plastic composites lead to different surface characteristics, which can influence weathering. In this study, 50% wood–flour‐filled high‐density polyethylene (HDPE) composite samples were injection molded, extruded, or extruded and then planed, to remove the manufacturing surface characteristics. Fourier transform infrared spectroscopy was used to chemically show the difference in surface components. The samples were weathered in a xenon‐arc weathering apparatus for 1000, 2000, and 3000 h and analyzed for color fade and loss of flexural modulus of elasticity and strength. Final color (lightness) after weathering was not dependent on the manufacturing method. However, the manufacturing method was related to mechanical property loss caused by weathering. Composites with more wood component at the surface (i.e., planed samples) experienced a larger percentage of total loss in flexural modulus of elasticity and strength after weathering. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1021–1030, 2004
Antimicrobial finishing of wool fabrics using quaternary ammonium salts
Authors: Zhu Ping , Sun Gang
Published: April 2004

Durable antimicrobial wool fabrics were prepared by using a simple chemical finishing process. Carboxylate groups in wool protein were employed to form ionic interactions with cationic antimicrobial agents, such as cetylpyridinium chloride (CPC) and other quaternary ammonium salts, under the isoelectric point of wool protein, and such interactions were proven effective. The uptakes of the agents were dependent on their chemical structures, pH values of treatment solutions, concentration of the agents, and treatment temperature. The ionic interactions between the agents and the protein could survive repeated laundering, with CPC showing the best durability among three tested quaternary ammonium salts. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1037–1041, 2004
Tubular‐Shaped Stoichiometric Chrysotile Nanocrystals
Authors: Falini Giuseppe , Foresti Elisabetta , Gazzano Massimo , Gualtieri Alessandro F. , Leoni Matteo , Lesci Isidoro G. , Roveri Norberto
Published: April 2004

Stoichiometric chrysotile tubular nanocrystals have been synthesized as possible starting materials for applications toward nanotechnology, and as a standard reference sample for the investigation of the molecular interactions between chrysotile, the most utilized asbestos, and biological systems. Chrysotile nanocrystals have been synthesized under controlled hydrothermal conditions, and have been characterized by chemical, morphological, structural, spectroscopic and microcalorimetric analyses. They show a constant “cylinder‐in‐cylinder” morphology constituted by two or three concentric subunits. Each single nanocrystal has a tubular shape of about 49±1 nm in outer maximum diameter, and a hollow core of about 7±1 nm. Structural investigation carried out on an X‐ray powder pattern allowed to improve the structural model proposed for chrysotile mineral samples. Synthetic chrysotile crystallizes in the monoclinic Cc space group with a=0.5340(1) nm, b=0.9241(1) nm, and c=1.4689(2) nm, β=93.66(3)°.
Mikroverfahrenstechnik – Ein Förderschwerpunkt des BMBF im Rahmen des Programms Mikrosysteme
Authors: Ackermann U.
Published: April 2004

No abstracts.
Fluidisches Bussystem für die chemische Verfahrenstechnik und für die Produktion von Feinchemikalien
Authors: Müller A. , Cominos V. , Hessel V. , Horn B. , Schürer J. , Ziogas A. , Jähnisch K. , Hillmann V. , Großer V. , Jam K. A. , Bazzanella A. , Rinke G. , Kraut M.
Published: April 2004

No abstracts.
Mischer mit mikrostrukturierten Folien für chemische Produktionsaufgaben
Authors: Werner B. , Hessel V. , Löb P.
Published: April 2004

Seit etwa 10 Jahren beschäftigt sich die Institut für Mikrotechnik Mainz GmbH (IMM) mit der Nutzung von Mikrostrukturen im Bereich der Mikroverfahrenstechnik. Deren Vorteile – effizienterer Wärmeaustausch und Massentransport – bewirken u. a. Steigerung von Ausbeute und Selektivität bei gleichzeitiger Ressourcenschonung. Die Entwicklung von mikrostrukturierten Mischern war dabei ein Schlüssel zu verbesserten Feinchemikaliensynthesen sowie zur Herstellung von Dispersionen, Cremes, Schäumen und Emulsionen. Bislang waren diese mikrostrukturierten Mischer im Wesentlichen auf Labor‐ oder bestenfalls Pilotanlagen‐Maßstab festgelegt – typische Maximalflussraten lagen bei 2 – 100 L/h für wasserähnliche Fluidsysteme. Mit der Einführung der StarLaminatoren StarLam300 und StarLam3000, konnte diese Grenze jetzt auf weit über 300 L/h bis in den m3/h‐Bereich angehoben werden. Beide Apparate zeigen gute Mischgüten bei hohen Flüssen, die durchaus an die sehr guten Werte von bisher bekannten Niederdurchsatz(L/h)‐Mikromischer heranreichen. Damit ist eine Kontinuität von „wirklichen”︁ Mikromischern über die hier beschriebenen Hochdurchsatz‐Tools bis zu statischen Mischern mit noch höheren Durchsätzen gegeben. Eine Klassifikation der Mischeffizienz nach dem Leistungseintrag bestätigt ebenso diese Kontinuität.
The cognitive sequelae of standard‐dose adjuvant chemotherapy in women with breast carcinoma
Authors: Wefel Jeffrey S. , Lenzi Renato , Theriault Richard L. , Davis Robert N. , Meyers Christina A.
Published: April 2004

BACKGROUND

Retrospective trials have reported that chemotherapy‐induced cognitive dysfunction was experienced by a subset of patients with breast carcinoma. However, recent evidence indicated that a subset also exhibited impaired cognitive function at baseline, before the start of chemotherapy. A prospective, longitudinal trial that incorporates baseline neuropsychologic evaluations is necessary to determine to what extent cognitive dysfunction is attributable to chemotherapy in this population.

METHODS

Eighteen women with breast carcinoma underwent a comprehensive neuropsychologic evaluation before treatment and at short‐term and long‐term intervals after chemotherapy. The incidence, nature, severity, and chronicity of cognitive dysfunction developing in patients with breast carcinoma treated with a standard dose of adjuvant chemotherapy were assessed.

RESULTS

Before the start of systemic therapy, 33% of women in the current cohort exhibited cognitive impairment. At the short‐term postchemotherapy time point, 61% of the cohort exhibited a decline relative to baseline in 1 or more domains of cognitive functioning and reported greater difficulty in maintaining their ability to work. The most common domains of cognitive dysfunction were related to attention, learning, and processing speed. At the long‐term postchemotherapy time point, approximately 50% of patients who experienced declines in cognitive function demonstrated improvement, whereas 50% remained stable. Self‐reported ability to perform work‐related activities also improved over this interval. Neither impairment at baseline nor subsequent treatment‐related cognitive decline exhibited any statistically significant correlation with affective well‐being or with demographic or clinical characteristics.

CONCLUSIONS

The current study is the first longitudinal trial to report evidence of an association between cognitive dysfunction and chemotherapy in a subgroup of women with nonmetastatic breast carcinoma. The importance of using prospective research designs, appropriate cognitive measures, and statistical methods to evaluate subgroup effects was discussed. Identification of mechanisms associated with cognitive dysfunction and of risk factors contributing to subgroup vulnerability is necessary. Cancer 2004. © 2004 by the American Cancer Society.
Drosophila eye disc margin is a center for organizing long‐range planar polarity
Authors: Lim Janghoo , Choi Kwang‐Wook
Published: April 2004

Planar polarity patterning involves long‐range signaling and signal transduction. In Drosophila eye, Dishevelled (Dsh) is not only crucial for cell‐autonomous transduction of a polarity signal(s) but is also involved in nonautonomous signaling function. To identify the sites for long‐range polarity signaling in eye disc, we examined spatial and temporal conditions for nonautonomous Dsh function. Here we show that Dsh and its downstream factor Armadillo (Arm) are required in the border region of eye disc between the peripodial membrane (PM) and the disc proper (DP) for nonautonomous signaling. Conditional misexpression of Dsh or Arm at the posterior margin of the disc was sufficient to induce nonautonomous polarity reversals. A critical time window for the induction of such changes was approximately coincident with the timing of morphogenetic furrow initiation. Our data suggest that the disc margin is an essential site for organizing planar polarity during the initial stage of retinal morphogenesis. genesis 39:26–37, 2004. © 2004 Wiley‐Liss, Inc.
Laser capture microdissection of fluorescently labeled embryonic cranial neural crest cells
Authors: Bhattacherjee Vasker , Mukhopadhyay Partha , Singh Saurabh , Roberts Emily A. , Hackmiller Rita C. , Greene Robert M. , Pisano M. Michele
Published: April 2004

Summary: This study is the first to report a unique genetic strategy to permanently label mammalian neural crest cells (NCC) with a fluorescent marker, selectively isolate the labeled NCC or their derivatives during murine ontogenesis by laser capture microdissection (LCM), and prepare molecular components, such as RNA, for selective gene expression analyses. Through utilization of a Cre recombinase/loxP system, a genetic strategy that has been used repeatedly to achieve tissue‐specific activation of reporter transgenes in mice, a novel two‐component mouse model was created in which neural crest cells (and their progeny) are indelibly marked throughout the pre‐ and postnatal lifespan of the organism. To generate this mouse model, a Wnt1‐Cre transgenic line was crossed with a mouse line expressing a conditional reporter transgene (“floxed” enhanced green fluorescent protein). Resulting offspring, expressing both the Wnt1‐Cre and “floxed” EGFP alleles, demonstrated EGFP expression in the NCC and all of their derivatives throughout embryonic, postnatal, and adult stages. In the present study, EGFP‐labeled cranial NCC from the first branchial arch of gestational day 9.5 murine embryos were visualized in frozen tissue sections and isolated by LCM under epifluorescence optics. RNA was extracted from “captured” cells and amplified by double‐stranded cDNA synthesis and in vitro transcription. Amplified mRNA samples from “captured” cells were evaluated by TaqMan quantitative, real‐time PCR for the expression of a panel of NCC gene markers. The molecular genetic strategy delineated in this report will facilitate future embryo‐genomic and ‐proteomic analyses of mammalian NCC that will serve to further our understanding of these pluripotent embryonic progenitor cells. genesis 39:58–64, 2004. © 2004 Wiley‐Liss, Inc.
Loss‐of‐imprinting of Peg1 in mouse interspecies hybrids is correlated with altered growth
Authors: Shi Wei , Lefebvre Louis , Yu Yang , Otto Sabine , Krella Antje , Orth Annie , Fundele Reinald
Published: April 2004

Previous studies have shown that loss‐of‐imprinting (LOI) is a regular occurrence in interspecies hybrids of the genus Peromyscus. Furthermore, evidence was presented that indicated that LOI is involved in a placental hybrid dysgenesis effect resulting in abnormal placental growth and thus possibly in speciation. We show here that LOI of the strictly paternally expressed gene Peg1 (also called Mest) occurs in F1 hybrids between Mus musculus (MMU) and M. spretus (MSP). Peg1 LOI is correlated with increased body weight and increased weight of two of the organs tested, kidney and spleen. X‐gal staining of tissues derived from Peg1+/‐ × MSP F1 mice, carrying a maternal LacZ knock‐in allele of Peg1, demonstrates that LOI is stochastic in that it affects different tissues to variable extents and that, even within one tissue, not all cells are similarly affected. Furthermore, this expression from the maternal allele does not necessarily follow the endogenous paternal Peg1 expression pattern. Our results indicate that LOI occurs in interspecies hybrids in the genus Mus and that altered growth is a frequent outcome of LOI. genesis 39:65–72, 2004. © 2004 Wiley‐Liss, Inc.
Poly(vinyl alcohol) membranes for adhesion prevention
Authors: Weis Christine , Odermatt Erich K. , Kressler Jörg , Funke Zofia , Wehner Tim , Freytag Dorothee
Published: April 2004

The abnormal joining of anatomic structures after abdominal and pelvic surgery can lead to such major complications as bowel obstruction or infertility. Poly(vinyl alcohol) (PVA) membranes and hydrogels were placed over the injured tissue to act as a physical barrier and prevent such adhesions from occurring in a rabbit sidewall model. The membranes were sutured into place to prevent their slipping or curling on the moist tissue. Various in vitro experiments (including testing for swelling and mechanical strength) were conducted in order to better understand the behavior of these membranes in the wound. The results showed that both the PVA membranes and PVA hydrogels significantly reduced the number and severity of adhesions in the rabbit sidewall model, and even indicated a distinct improvement over SEPRAFILM® as antiadhesion barriers. Contact‐angle measurements were taken in order to evaluate the surface properties of the membranes and hydrogels. Three approaches were taken to render the membranes more bioadhesive, and forego the need for future additional suturing: imprinting a texture onto the membrane, coating the membrane with carboxy methyl cellulose (CMC), and producing bi‐layered, porous PVA membranes through a process of lyophilization. Though the surface of the PVA hydrogels is more hydrophilic than the surface of the PVA membranes, neither would adhere untreated to moist tissue. However, all three approaches aimed at improving their bioadhesion yielded excellent results and demonstrated that PVA could indeed be considered a viable method of adhesion prevention. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 70B: 191–202, 2004
Disruption of the actin cytoskeleton results in nuclear factor‐κB activation and inflammatory mediator production in cultured human intestinal epithelial cells
Authors: Németh Zoltán H. , Deitch Edwin A. , Davidson Marson T. , Szabó Csaba , Vizi E. Sylvester , Haskó György
Published: April 2004

The cytoskeleton in eukaryotic cells is composed of two major filament systems, the microtubule system and the actin cytoskeleton. The microtubule system has recently emerged as an important regulator of NF‐κB function. However, the role that the actin microfilament system plays in controlling NF‐κB activation is incompletely understood. In this study, we examined the effect of actin cytoskeleton disruption on NF‐κB activation in human intestinal epithelial cells. Treatment of HT‐29 or Caco‐2 cells with the prototypic actin disrupting agents cytochalasin D or latrunculin B resulted in increased NF‐κB DNA binding and NF‐κB‐dependent transcriptional activity. This NF‐κB activation by cytochalasin D was secondary to an effect on IκB, because cytochalasin D‐induced IκB degradation and the cytochalasin D‐induced increase in NF‐κB‐dependent transcriptional activity was prevented by a dominant negative IκB mutant. Exposure of the cells to cytochalasins or latrunculin B increased gene expression and release of the NF‐κB‐dependent chemokines IL‐8 and GRO‐α. Cytochalasin D also activated p38 MAP kinase, which pathway contributed to the cytochalasin D‐induced increase in IL‐8 production. These results demonstrate that the actin cytoskeleton plays an important role in the regulation of NF‐κB activation and inflammatory events in intestinal epithelial cells. J. Cell. Physiol. 200: 71–81, 2004. © 2004 Wiley‐Liss, Inc.
Design and processing of a thermoplastic composite reinforced wood structure
Authors: Dai Heming , Smith Michael J. , Ramani Karthik
Published: April 2004

Reinforced wood structures retain the advantages of natural wood while they allow increased life and better performance. Wood reinforced with thermoset composites has been studied earlier. We for the first time develop a process and design methodology for a thermoplastic‐reinforced wood structure. A wood floor structure was reinforced by the means of adhering a thin layer of consolidated thermoplastic composite. The process for consolidating commingled E‐glass/polypropylene yarns and adhering the composite to wood was designed and tested. The time for preheating and consolidating the commingled thermoplastic yarns on top of wood was predicted analytically and compared with experimental results. An optimal design methodology for the wood/composite floor structure is also developed. Polym. Compos. 25:119–133, 2004. © 2004 Society of Plastics Engineers.
Numerical predictions of 3‐D filler orientation and elastic compliance for reinforced plastics containing fillers with aspect ratio distribution
Authors: Shiraishi Yutaka , Narazaki Norio , Kikutani Takeshi
Published: April 2004

In the injection molding of parts containing 30 wt% short‐glass‐fiber or glass‐flake, filler orientation distribution functions and elastic constants are predicted, taking into account the aspect ratio distribution of fillers. The filler orientation distribution functions and the elastic compliance tensors are estimated by using Advani's method and Wakashima's method, respectively. The estimated filler orientation distributions in composite parts reinforced with short‐glass‐fiber or glass‐flake agree with soft X‐ray photograph observations. The fiber orientation distribution function, predicted for interaction coefficient CI = 0.01, is close to the experimental results. Based on this orientation distribution, the elastic compliance tensor distributions are predicted on the assumption that the filler aspect ratio can be presented by a circumscribed filler aspect ratio or an equivalent filler aspect ratio. As a result, the vibration behavior predicted by adopting the equivalent aspect ratio agrees with the experimental results. Polym. Compos. 25:194–213, 2004. © 2004 Society of Plastics Engineers.
Process‐induced internal stresses in phenol‐formaldehyde cellulose composites
Authors: Doyle M. A. , Hagstrand P.‐O. , Månson J.‐A. E.
Published: April 2004

Phenol and melamine‐formaldehyde (PF and MF) cellulose composites are being used extensively in the laminate industry. Despite their many advantages, flat panels produced from such materials have a tendency to warp immediately after processing as well as during subsequent service. This report presents results of an investigation into the thermoviscoelastic properties and the process‐induced internal stresses of PF cellulose composites. Thermoelastic properties were measured using Electronic Speckle Pattern Interferometry (ESPI), Thermo Mechanical Analysis (TMA) and Dynamic Mechanical Analysis (DMA). This latter was also employed in order to build a time‐temperature relaxation superposition for PF cellulose. Process‐induced internal stresses were quantified via a modified beam‐bending technique that allowed for consolidation pressure to be applied on the materials. Results from the study showed the following: anisotropy in thermoelastic properties due to the oriented cellulose fiber network, a clear viscoelastic response allowing time‐temperature superposition in a bi‐phase material, and high levels of internal stress build‐up on cure. Polym. Compos. 25:214–228, 2004. © 2004 Society of Plastics Engineers.
Complex folding pathways in a simple β‐hairpin
Authors: Wei Guanghong , Mousseau Normand , Derreumaux Philippe
Published: April 2004

The determination of the folding mechanisms of proteins is critical to understand the topological change that can propagate Alzheimer and Creutzfeld‐Jakobs diseases, among others. The computational community has paid considerable attention to this problem; however, the associated time scale, typically on the order of milliseconds or more, represents a formidable challenge. Ab initio protein folding from long molecular dynamics simulations or ensemble dynamics is not feasible with ordinary computing facilities and new techniques must be introduced. Here we present a detailed study of the folding of a 16‐residue β‐hairpin, described by a generic energy model and using the activation‐relaxation technique. From a total of 90 trajectories at 300 K, three folding pathways emerge. All involve a simultaneous optimization of the complete hydrophobic and hydrogen bonding interactions. The first two pathways follow closely those observed by previous theoretical studies (folding starting at the turn or by interactions between the termini). The third pathway, never observed by previous all‐atom folding, unfolding, and equilibrium simulations, can be described as a reptation move of one strand of the β‐sheet with respect to the other. This reptation move indicates that non‐native interactions can play a dominant role in the folding of secondary structures. Furthermore, such a mechanism mediated by non‐native hydrogen bonds is not available for study by unfolding and Gō model simulations. The exact folding path followed by a given β‐hairpin is likely to be influenced by its sequence and the solvent conditions. Taken together, these results point to a more complex folding picture than expected for a simple β‐hairpin. Proteins 2004;9999:000–000. © 2004 Wiley‐Liss, Inc.
Cytosolic sialidase Neu2 upregulation during PC12 cells differentiation
Authors: Fanzani A. , Colombo F. , Giuliani R. , Preti A. , Marchesini S.
Published: April 2004

The enzymatic activity of cytosolic sialidase Neu2 was found to increase transiently only during differentiation, whereas was undetectable in untreated PC12 cells. These data suggest a possible involvement of cytosolic sialidase Neu2 in differentiation of PC12 cells.
Sites of positive allosteric modulation by neurosteroids on ionotropic γ‐aminobutyric acid receptor subunits
Authors: Ueno Susumu , Tsutsui Masato , Toyohira Yumiko , Minami Kouichiro , Yanagihara Nobuyuki
Published: April 2004

Neurosteroids are known as allosteric modulators of ionotropic γ‐aminobutyric acid (GABA) receptors. Here, we investigated sites of positive allosteric modulation by allotetrahydrodeoxycorticosterone (5α‐THDOC) at GABA receptors using the technique of chimeragenesis and the Xenopus oocyte expression system. Our findings have demonstrated that the region from transmembrane segment (TM) 4 to the C‐terminus of the GABAA receptor α1 subunit is crucial for the action of 5α‐THDOC, but insufficient for the action of another neurosteroid allopregnanolone, suggesting that a specific region critical for neurosteroid action at GABA receptors exists in the domain between TM4 and the C‐terminus of GABA receptor subunits.
Wet early to middle Holocene conditions on the upper Coastal Plain of North Carolina, USA
Authors: Goman Michelle , Leigh David S
Published: April 2004

A peat core from a cutoff paleochannel of Little River on the upper Coastal Plain of North Carolina provides a continuous pollen record of environmental change for the past 10,500 years and includes a sedimentary record of overbank floods. Palynological and sedimentary data indicate that the early to middle Holocene was wetter than previously suggested from lake sites in the southeastern United States. The period from 9000 to 6100 cal yr B.P. is characterized by high pollen percentages of Nyssa and Quercus, but low percentages of Pinus. Fifteen large overbank flood events are present within this period (5 floods/1000 yr). In contrast, only 6 large overbank flood events occurred since 6100 cal yr B.P. (1 flood/1000 yr). The increases in moisture and flood events probably were controlled by changes in atmospheric circulation related to shifts in the position of the Bermuda High, sea surface temperatures, and El Niño activity that together may have affected the frequency of large floods generated from tropical storms in the region.
The phenology of Sarcosagium campestre observed over three years
Authors: Gilbert Oliver L.
Published: April 2004

A small number of lichens produce ephemeral fruit bodies that last for less than a year, they belong to genera such as Absconditella, Epigloea, Sarcosagium, Steinia, Thelocarpon and Vezdaea. Many are found in transient, terricolous, often man-made habitats and niches where competition is low. Poelt and Vežda (1990) have reviewed the sparse literature on ephemeral lichens. Since then, a two year study of Thelocarpon laureri in the Sheffield area (Gilbert 2001), has shown this species behaving as a spring ephemerophyte, the number of fruits peaking in April and May. Colonies persisted for 18 months (two fruiting periods). This short paper extends such observations to Sarcosagium campestre.
A new species of Solenopsora from Tasmania
Authors: KANTVILAS Gintaras
Published: April 2004

The new species, Solenopsora tasmanica Kantvilas, is described and its distinguishing characteristics are discussed. The new species is the first record for the genus for Tasmania and occurs on montane, acidic soils, an unusual habitat for Solenopsora. It also contains the compounds brialmontin 1 and brialmontin 2, recorded from Solenopsora for the first time.
A reassessment of the genera Chromatochlamys and Thelenella, and a new species of Strigula from the British Isles
Authors: FRYDAY Alan M. , COPPINS Brian J.
Published: April 2004

Strigula confusa Fryday, Coppins & Common is described from the western British Isles, where it grows over bryophytes on mildly basic rocks. The concept of the genus Thelenella is expanded to include Chromatochlamys and the following new combinations are made: Thelenella larbalestieri (A. L. Sm.) Coppins & Fryday, Thelenella muscorum var. octospora (Nyl.) Coppins & Fryday, Thelenella vezdae (H. Mayrhofer & Poelt) Coppins & Fryday. Thelenella sordidula (Th. Fr.) H. Mayrhofer is reported for the first time from Europe (Svalbard).
Literature on lichens and biodeterioration of stonework. IV
Authors: PIERVITTORI R. , SALVADORI O. , ISOCRONO D.
Published: April 2004

Each reference is numbered progressively and is characterized by publication details, a brief abstract and one or more abbreviations referring to specific themes. The list is followed by an Analytical Index of the different themes, showing the numbers corresponding to the appropriate references in the Bibliographic list. A new topic (RV) has been introduced to identify the review articles.
ACKNOWLEDGEMENTS
Authors: Editor Journal
Published: April 2004

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ONTOGENY OF THE FRUITS OF TWO ANOMALOUS AFRICAN WOODY GENERA, POLEMANNIOPSIS AND STEGANOTAENIA (APIACEAE), AND THEIR PHYLOGENETIC RELATIONSHIP
Authors: LIU M. (REBECCA) , VAN WYK B-E. , TILNEY P. M.
Published: April 2004

The fruits of two anomalous African woody Apiaceae, Polemanniopsis marlothii and Steganotaenia araliacea, differ in structure when mature though the ovaries are very similar, both being heteromorphic in young flower stage. This unexpected heteromorphism in S. araliacea has important implications for future studies of basal genera and the interpretation of fruit characters in general. Both taxa also have unique ‘intrajugal cavities’ in the ovaries and fruits, which supports the idea that the two genera are closely related, sharing some characters with the Hydrocotyloideae and Saniculoideae. This provides morphological and anatomical evidence to support the previous hypotheses on their relationship with Saniculoideae. Their basal position is also supported by characters shared with other basal genera previously included in Hydrocotyloideae, such as the lateral wings and slightly lignified endocarp in Polemanniopsis and Steganotaenia.
THE GESNERIACEAE OF SULAWESI III: THREE NEW SPECIES OF AESCHYNANTHUS
Authors: MENDUM M.
Published: April 2004

Three new species of Aeschynanthus (Gesneriaceae) from Sulawesi (Celebes), A. batesii, A. burttii and A. lobaticalyx, are described and illustrated. The phylogenetic position of A. batesii and A. lobaticalyx is briefly discussed; A. burttii has not yet been sequenced.
A SYNOPSIS OF CYTOLOGICAL STUDIES IN GESNERIACEAE
Authors: MÖLLER M. , KIEHN M.
Published: April 2004

Our knowledge of cytological data published on members of the family Gesneriaceae is summarized and critically evaluated in the light of current taxonomic treatments and phylogenetic hypotheses. There are about 1000 published chromosome counts, covering 56% of the genera but only 18% of the species. In particular the New World tribes Beslerieae and Napeantheae and the Old World tribe Didymocarpeae are underexplored at generic level. In Gesneriaceae chromosome data are a valuable source of taxonomic characters. From our current knowledge of the phylogenetic relationships in the family we know that basic chromosome numbers in the New World subfamily Gesnerioideae appear to be rather conserved, but that a more complex pattern of genome evolution seems to be present among the Old World tribes. Both polyploidy and dysploid changes have played a significant role in the evolution of the family. However, the number of species for which both cytological and molecular data are available is at present too low to reach firm conclusions on ancestral basic chromosome numbers, particularly for the Old World group. To facilitate wider access to cytological data on the Gesneriaceae, a website has been developed (http://www.rbge.org.uk/rbge/web/search/index.jsp), which is introduced in this paper.
A NEW SPECIES OF CAULOKAEMPFERIA (ZINGIBERACEAE) FROM LAOS
Authors: LARSEN K. , JENJITTIKUL T.
Published: April 2004

The genus Caulokaempferia (Zingiberaceae) is recorded for the first time from Laos with the description and illustration of the new species C. burttii.
A NEW SPECIES OF CAULOKAEMPFERIA (ZINGIBERACEAE) FROM THAILAND
Authors: SUKSATHAN P. , TRIBOUN P.
Published: April 2004

The new species Caulokaempferia larsenii (Zingiberaceae) from northern Thailand is described and illustrated.
Cladistics: A Practical Primer on CD-ROM. Peter Skelton, Andrew Smith & Neale Monks. Cambridge University Press. 2002. 92pp. ISBN 0 521 52341 9. £29.95 (hardback).
Authors: Milton J. J.
Published: April 2004

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