bluuebunny/crossref_metadata_2025_split huggingface dataset:
Apoptotic Killing and Phagocytosis of Host Cells by the ParasiteEntamoeba histolytica
Authors: Huston Christopher D. , Boettner Douglas R. , Miller-Sims Vanessa , Petri, William A. 
Published: January 2003

ABSTRACTThe ability ofEntamoeba histolyticato kill and phagocytose host cells correlates with parasite virulence. This study addressed the role of apoptotic cell killing and host cell phosphatidylserine exposure in the subsequent phagocytosis of Jurkat T cells byE. histolytica. Ingested host cells were apoptotic, as evidenced by the activation of caspase 3 in 88% ± 3% (mean and standard deviation [SD] of the mean) of Jurkat cells engulfed byE. histolytica; ingested cells without detectable active caspase 3 were already disrupted and partially digested. That apoptotic cell killing preceded phagocytosis was supported by the demonstration that a higher percentage of amebae ingested apoptotic cells than ingested healthy cells (62% ± 7% versus 30% ± 9%, respectively [mean and SD]) (P= 0.008).E. histolyticaalso ingested apoptotic Jurkat cells more rapidly than necrotic control cells (8.5% ± 0.4% versus 3.5% ± 0.7%, respectively [mean and SD]) (P< 0.001). The inhibition of amebic cytotoxicity withd-galactose (which blocks the amebic Gal/GalNAc lectin) blocked the phagocytosis of healthy cells by greater than 80%, providing further evidence that apoptosis preceded engulfment. In contrast,d-galactose blocked the phagocytosis of already apoptotic cells by only 40%, implicating an additional host ligand (besidesd-galactose) in amebic engulfment of apoptotic cells. The most characteristic surface change on apoptotic cells is phosphatidylserine exposure. Consistent with a role for host cell phosphatidylserine exposure in amebic ingestion of killed cells, Jurkat cell phosphatidylserine was exposed during incubation withE. histolytica(27% ± 1% [mean and SD] specific increase at 30 min) (thePvalue versus the control was 0.0003). Approximately 50% more amebae ingested viable Jurkat cells expressing phosphatidylserine on the outer leaflet of the plasma membrane than ingested control cells (30.3% ± 2.2% versus 19.8% ± 1.9%, respectively [mean and SD]) (P= 0.003). By analogy with phagocytic clearance during apoptosis in metazoans, amebic apoptotic host cell killing followed by phagocytosis may limit inflammation and enable amebae to evade the host immune response.
Restricted Fusion of
Chlamydia trachomatis
Vesicles with Endocytic Compartments during the Initial Stages of Infection
Authors: Scidmore Marci A. , Fischer Elizabeth R. , Hackstadt Ted 
Published: January 2003

ABSTRACT

The chlamydial inclusion occupies a unique niche within the eukaryotic cell that does not interact with endocytic compartments but instead is fusogenic with a subset of sphingomyelin-containing exocytic vesicles. The
Chlamydia trachomatis
inclusion acquires these distinctive properties by as early as 2 h postinfection as demonstrated by the ability to acquire sphingomyelin, endogenously synthesized from 6{
N
-[(7-nitrobenzo-2-oxa-1,3-diazol-4-yl)amino]caproylsphingosine} (C
6
-NBD-ceramide). The molecular mechanisms involved in transformation of the properties and cellular interactions of the inclusion are unknown except that they require early chlamydial transcription and translation. Although the properties of the inclusion are established by 2 h postinfection, the degree of interaction with endocytic pathways during the brief interval before fusogenicity with an exocytic pathway is established is unknown. Using a combination of confocal and electron microscopy to localize endocytic and lysosomal markers in
C. trachomatis
infected cells during the early stages of infection, we demonstrate a lack of these markers within the inclusion membrane or lumen of the inclusion to conclude that the nascent chlamydial inclusion is minimally interactive with endosomal compartments during this interval early in infection. Even when prevented from modifying the properties of the inclusion by incubation in the presence of protein synthesis inhibitors, vesicles containing elementary bodies are very slow to acquire lysosomal characteristics. These results imply a two-stage mechanism for chlamydial avoidance of lysosomal fusion: (i) an initial phase of delayed maturation to lysosomes due to an intrinsic property of elementary bodies and (ii) an active modification of the vesicular interactions of the inclusion requiring chlamydial protein synthesis.
DEVIATION ALGORITHMS FOR RANKING SHORTEST PATHS
Authors: DE QUEIRÓS VIEIRA MARTINS ERNESTO , PASCOAL MARTA MARGARIDA BRAZ , SANTOS JOSÉ LUIS ESTEVES DOS 
Published: January 2003

The shortest path problem is a classical network problem that has been extensively studied. The problem of determining not only the shortest path, but also listing the K shortest paths (for a given integer K>1) is also a classical one but has not been studied so intensively, despite its obvious practical interest. Two different types of problems are usually considered: the unconstrained and the constrained K shortest paths problem. While in the former no restriction in considered in the definition of a path, in the constrained K shortest paths problem all the paths have to satisfy some condition – for example, to be loopless. In this paper new algorithms are proposed for the uncontrained problem, which compute a super set of the K shortest paths. It is also shown that ranking loopless paths does not hold in general the Optimality Principle and how the proposed algorithms for the unconstrained problem can be adapted for ranking loopless paths.
OPTIMAL LAYOUT OF TRIVALENT CAYLEY INTERCONNECTION NETWORKS
Authors: CALAMONERI TIZIANA , PETRESCHI ROSSELLA 
Published: January 2003

In this paper we deal with the layout of Trivalent Cayley Interconnection Networks. Namely, we prove that a lower bound on their layout area is Ω(2n-1× 2n-1) and we exhibit some methods to lay these networks out in O(2n-1× 2n-1). We piont out that these layout methods work for other networks decomposable into equal length cycles connected by following fixed rules.
TRANSFER EQUIVALENCE AND REALIZATION OF NONLINEAR HIGHER ORDER INPUT/OUTPUT DIFFERENCE EQUATIONS USING MATHEMATICA
Authors: KOTTA ÜLLE , TÕNSO MARIS 
Published: January 2003

This paper presents a contribution to the development of symbolic computation tools for discrete-time nonlinear control systems. A set of functions is developed in Mathematica 3.0 that test if the higher order input/output difference equation is realizable in the classical state-space form, and for simple examples, also find such state equations. The approach relies on a new notion of equivalence of higher order difference equations which yields a minimal (i.e. accessible and observable) realization and generalizes the notion of transfer equivalence to the nonlinear case. The application of the developed functions is demonstrated on three examples obtained via identification.
Sulfenamide-catalyzed Oxidation of Primary and Secondary Alcohols with Molecular Bromine
Authors: Matsuo Jun-ichi , Kawana Asahi , Yamanaka Hiroyuki , Mukaiyama Teruaki 
Published: January 2003

Abstract
Primary and secondary alcohols were smoothly oxidized to the corresponding aldehydes and ketones in high yields at room temperature with 1.1 equiv. of molecular bromine by using a catalytic amount of N-t-butyl-2-nitrobenzenesulfenamide in the coexistence of potassium carbonate and molecular sieves 4A.
Surface Modification of Ordered Mesoporous Silica with an Organosilane Containing Polyethylene Oxide Groups to Retain the Hydrophilic Nature
Authors: Kimura Tatsuo , Suzuki Makiko , Tomura Shinji , Oda Kiichi 
Published: January 2003

Abstract
The ability to adsorb water of ordered mesoporous silica was successfully controlled by organic modification with an organoalkoxysilane containing polyethylene oxide groups.
Higher Water Intrusion Property on Novel Porous Matrix Composed of Bioinspired Polymer Stereocomplex for Tissue Engineering
Authors: Watanabe Junji , Ishihara Kazuhiko 
Published: January 2003

Abstract
A porous matrix composed of bioinspired phospholipid polymers with enantiomeric poly(lactic acid) segments in side chain, were prepared by formation of stereocomplex between them and characterized for use as new cell culture matrix.
TiNxOyFz as a Stable Photocatalyst for Water Oxidation in Visible Light (&lt;570 nm)
Authors: Nukumizu Kohta , Nunoshige Jun , Takata Tsuyoshi , Kondo Junko N , Hara Michikazu , Kobayashi Hisayoshi , Domen Kazunari 
Published: January 2003

Abstract
TiNxOyFz prepared from (NH4)2TiF6 and SiO2 under NH3 flow at 773 K has a bandgap-absorption edge at about 570 nm and functions as a stable photocatalyst for water oxidation.
Graft copolymerization of nitrile monomers onto sulfonated jute‐cotton blended fabric
Authors: Mondal Ibrahim H. 
Published: January 2003

AbstractGraft copolymerization of nitrile monomers, such as acrylonitrile and methacrylonitrile, onto bleached sulfonated jute‐cotton blended fabric was carried out in an aqueous medium using potassium permanganate as an initiator under the catalytic influence of sulfuric acid in a nitrogen atmosphere. The effect of concentrations of monomer, permanganate, sulfuric acid, reaction time, and reaction temperature on the percent graft yield was studied. The percent graft yield was found to be dependent on the above‐mentioned variables. On the basis of experimental findings, an optimum condition for effective grafting is suggested. As evidence of polymer grafting, some instrumental analyses, such as thermogravimetric analysis, infrared spectroscopy, and X‐ray diffractometry were carried out. Grafting improved the thermal stability, protected from photo‐oxidative degradation, affected dyeability, and had a positive impact on color fastness. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2262–2266, 2003
Surface photografting polymerization of vinyl acetate, maleic anhydride, and their charge‐transfer complex. IV. Maleic anhydride
Authors: Jianping Deng , Wantai Yang 
Published: January 2003

AbstractIn general, it has been accepted that maleic anhydride (MAH) cannot be homopolymerized under normal conditions. However, MAH can be grafted onto substrates under UV irradiation rather easily. In this study, the photografting polymerization of MAH was examined with low‐density polyethylene (LDPE) film as a substrate. The initiating performances of different photoinitiators, including benzophenone (BP), Irgacure 651, and benzoyl peroxide (BPO), were examined. The effects of some principal factors, such as the temperature, solvent, and UV intensity, on the grafting polymerization of MAH were also investigated. The results show that MAH can be smoothly grafted onto LDPE film by UV radiation. Enhancing the intensity of UV radiation and elevating the irradiation temperature facilitate the grafting polymerization of MAH. Among BP, Irgacure 651, and BPO, Irgacure 651 can initiate the polymerization of more MAH, but BP is more effective for the initiation of surface grafting polymerization. Solvents of MAH also have a great influence on the grafting polymerization; some of them even seem to take part in the reaction. The occurrence of photografting polymerization was verified with Fourier transform infrared and electron spectroscopy for chemical analysis spectra. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2318–2325, 2003
Thermal and kinetic study of radical polymerization I. Melt state bulk polymerization of acrylamide by DSC
Authors: Mahdavian Ali‐Reza , Zandi Mojgan 
Published: January 2003

AbstractRadical‐initiated bulk polymerization of acrylamide in the presence of potassium persulfate in the melt phase has been investigated by differential scanning calorimetry (DSC). The method presented here has been carried out in isothermal condition. This not only saves energy and time but also has some less probable side effects. Side effects such as evaporation and imidization could affect the final yield and properties of the obtained product. Different temperatures have been examined for isothermal polymerization to find out the optimum temperature with complete conversion of acrylamide to its corresponding polymer. During the polymerization process, high‐molecular‐weight polyacrylamide is being produced without any significant loss in total yield. The molecular weight was determined by inherent viscosity measurement. Also, no side reaction such as imidization resulting in partial insolubility or crosslinked product was being observed. It is noteworthy that we believe DSC studies show the existence of living radicals that has not been reported before. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2335–2340, 2003
Synthesis of butyl rubber in hexane using a mixture of Et2AlCl and EtAlCl2 in the initiating system
Authors: Gronowski Adam A. 
Published: January 2003

AbstractA method was studied to obtain butyl rubber in hexane at −75 and −60°C using a mixture of a major amount of diethylaluminum chloride and a minor amount of ethylaluminum dichloride in the initiating system. The Jaacks method was used to determine the monomer reactivity ratio of isobutylene in copolymerization with isoprene in hexane at −75°C with the above initiating system; rIB = 1.54 ± 0.06. This value was different from a literature value rIB = 1.08 when just EtAlCl2 was used in hexane at −80°C. The mixture of both alkylaluminum chlorides in the initiating solution was subsequently directly activated with minute amounts of water or methylaluminoxane (MAO). The use of the modified initiators resulted in higher molecular weights, higher degrees of conversion, and higher isoprene contents in the butyl rubber. At the same time, temperature control was good during polymerizations. With modified alkylaluminum halides, the monomer reactivity ratio of isobutylene in copolymerization with isoprene in hexane at −75°C was close to unity, similar to the reported case with just EtAlCl2. The system activated with MAO made it possible to synthesize butyl rubber in hexane at −60°C having main characteristics typical of commercial butyl rubber manufactured in methyl chloride at −95°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2360–2364, 2003
Paradoxes of eukaryotic DNA replication: MCM proteins and the random completion problem
Authors: Hyrien Olivier , Marheineke Kathrin , Goldar Arach 
Published: January 2003

AbstractEukaryotic DNA replication initiates at multiple origins. In early fly and frog embryos, chromosomal replication is very rapid and initiates without sequence specificity. Despite this apparent randomness, the spacing of these numerous initiation sites must be sufficiently regular for the genome to be completely replicated on time. Studies in various eukaryotes have revealed that there is a strict temporal separation of origin “licensing” prior to S phase and origin activation during S phase. This may suggest that replicon size must be already established at the licensing stage. However, recent experiments suggest that a large excess of potential origins are assembled along chromatin during licensing. Thus, a regular replicon size may result from the selection of origins during S phase. We review single molecule analyses of origin activation and other experiments addressing this issue and their general significance for eukaryotic DNA replication. BioEssays 25:116–125, 2003. © 2003 Wiley Periodicals, Inc.
Closing the (Ran)GAP on segregation distortion in Drosophila
Authors: Kusano Ayumi , Staber Cynthia , Chan Ho Yin Edwin , Ganetzky Barry 
Published: January 2003

AbstractSegregation Distorter (SD) is a meiotic drive system in Drosophila that causes preferential transmission of the SD chromosome from SD/SD+ males owing to induced dysfunction of SD+ spermatids. Since its discovery in 1956, SD and its mode of action have baffled biologists. Recently, substantial progress has been made in elucidating this puzzle. Sd, the primary gene responsible for distortion encodes a mutant RanGAP, a key protein in the Ran signaling pathway required for nuclear transport and other nuclear functions. The mutant protein is enzymatically active but mislocalized to nuclei, which apparently disrupts Ran signaling by reducing intranuclear Ran‐GTP levels. Some evidence suggests that a defect in nuclear transport may be the main cause of sperm dysfunction. Although important questions remain, the basic mechanism of distortion is now understood sufficiently well that specific hypotheses can be formulated and tested. This previously mysterious genetic system may now offer unique insights into novel aspects of regulation by Ran. BioEssays 25:108–115, 2003. © 2003 Wiley Periodicals, Inc.
Proline‐directed phosphorylation and isomerization in mitotic regulation and in Alzheimer's Disease
Authors: Lu Kun Ping , Liou Yih‐Cherng , Vincent Inez 
Published: January 2003

AbstractThe reversible phosphorylation of proteins on serine/threonine residues preceding proline (Ser/Thr‐Pro) is a major regulatory mechanism for the control of a series of cell cycle events. Although phosphorylation is thought to regulate protein function by inducing conformational changes, little is known about most of these conformational changes and their significance. Recent studies indicate that the conformation and function of a subset of these phosphorylated proteins are controlled by the prolyl isomerase Pin1 through isomerization of specific phosphorylated Ser/Thr‐Pro bonds. Furthermore, compelling evidence supports the idea that proline‐directed phosphorylation and subsequent isomerization play a critical role not only in cell cycle control, but also in the development of Alzheimer's disease, where postmitotic neurons display various cell cycle markers, especially mitotic events, prior to degeneration. BioEssays 25:174–181, 2003. © 2003 Wiley Periodicals, Inc.
When parsimony backfires: Neglecting DNA repair may doom neurons in Alzheimer's disease
Authors: Nouspikel Thierry , Hanawalt Philip C. 
Published: January 2003

AbstractTaking advantage of the fact that they need not replicate their DNA, terminally differentiated neurons only repair their expressed genes and largely dispense with the burden of removing damage from most of their genome. However, they may pay a heavy price for this laxity if unforeseen circumstances, such as a pathological condition like Alzheimer's disease, cause them to re‐enter the cell cycle. The lifetime accumulation of unrepaired lesions in the silent genes of neurons is likely to be significant and may result in aborting the mitotic process and triggering cell death if the cells attempt to express these dormant genes and resume DNA replication. BioEssays 25:168–173, 2003. © 2003 Wiley Periodicals, Inc.
Visualization of molecular and cellular events with green fluorescent proteins in developing embryos: a review
Authors: Yu Yong A. , Oberg Kerby , Wang Gefu , Szalay Aladar A. 
Published: January 2003

AbstractAn Erratum has been published for this article in Luminescence (2003) 18(4) 243
During the past 5 years, green fluorescent protein (GFP) has become one of the most widely used in vivo protein markers for studying a number of different molecular processes during development, such as promoter activation, gene expression, protein trafficking and cell lineage determination. GFP fluorescence allows observation of dynamic developmental processes in real time, in both transiently and stably transformed cells, as well as in live embryos. In this review, we include the most up‐to‐date use of GFP during embryonic development and point out the unique contribution of GFP visualization, which resulted in novel discoveries. Copyright © 2002 John Wiley & Sons, Ltd.
Assessment of training effects on activity levels of alveolar macrophage in matured rats using chemiluminescent technique
Authors: Kumae Takashi , Arakawa Hatsuko 
Published: January 2003

AbstractChemiluminescence responses have been used for the evaluation of phagocyte function. In this study, to evaluate effects of training started after maturation on pulmonary immunity, the activity levels of rat alveolar macrophages (AMs) were assessed as reactive oxygen species (ROS) generating capacity, measured by lucigenin‐ and luminol‐dependent chemiluminescence, using a parallel luminometer. One group of male Wistar rats started training at 11 weeks old and another group at 17 weeks old. The experimental period was 12 weeks, and about half of the rats were sacrificed after 6 weeks. The forced and voluntary exercises affect the mean levels of body weights and cell populations in the bronchoalveolar lavage fluid in younger animals; however, the voluntary exercise group in younger animals seemed to adapt after 12 weeks. By contrast, chemiluminescence responses in older rats observed after 6 weeks suggest that AMs are primed, and the maximum releasing activities of ROS are reduced. These changes in AM activity may be caused by the exercise and separation stresses and the rats may adapt to those stressors after 12 weeks. The chemiluminescent technique is thought to be useful to evaluate the changes of AM activity. Copyright © 2002 John Wiley & Sons, Ltd.
Imaging of ultra‐weak bio‐chemiluminescence and singlet oxygen generation in germinating soybean in response to wounding
Authors: Chen Wen Li , Xing Da , Tan ShiCi , Tang YongHong , He Yonghong 
Published: January 2003

AbstractUltra‐weak bio‐chemiluminescence (UBC) from germinating soybean (Glycine max L. Merr) cotyledon under mechanical wounding was observed using a high‐sensitivity imaging system based on an ICCD detector and a highly sensitive single photon counter (SPC) device. The UBC imaging showed that the intensity at the injury location on a wounded cotyledon was obviously enhanced as compared with that at the non‐injured point. The UBC intensity of wounded cotyledons was initially very high and reached a stationary state after about 5 min. Wounding‐induced emission could be suppressed by wounding in the presence of sodium azide. Deuterium oxide amplified the emission intensity. It was concluded that singlet oxygen (1O2) was the main cause of the emission during the wounding phase. Copyright © 2002 John Wiley & Sons, Ltd.
College of DuPage Teaching and Learning Center: A comprehensive professional development program
Authors: Troller Karen T. 
Published: January 2003

AbstractAn important goal for professional development is the creation of a place where all faculty and staff can come together and learn. In this chapter, I describe how the College of DuPage in Glen Ellyn, Illinois, integrated its traning efforts by creating a teaching and learning center. This center provides development opportunities for all employees.
Magnetic resonance spectrometer controller and data postprocessing software
Authors: De Alejo R. Pérez , Álvarez E. , Rodríguez I. , Rodríguez E.M. , Villa P. , Piña D. , Shelton R. , Ruiz‐Cabello J. , Cortijo M. 
Published: January 2003

AbstractFreeware called MRS_Controller and written for Windows is described. It may be used to control magnetic resonance spectrometers or postprocess data, and is composed of four modules that may carry out field stabilization, graphical pulse sequence edition, experiment planning, and spectral data postprocessing. The control of a commercial Tesla BS587A spectrometer was performed with this software through an independent dynamic link library. It may easily be rewritten to allow the control of other types of spectrometers. This software can also be used for spectral data postprocessing and for planning or preparing experiments offline because hardware access is disabled when an instrument is not detected at startup. © 2003 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 16B: 1–14, 2003