bluuebunny/crossref_metadata_2025_split huggingface dataset:
The boundaries of cellular pathology: how pathologists see their clinical role
Authors: Jenkins David , Philips Zoë , Grisaffiî Kate , Whynes David K. 
Published: October 2002

AbstractThere has been much recent public attention on the effects of the practices of cellular pathology on patients and their relatives. It is important to establish clearly pathologists' views about their professional relationships to clinicians and patients. A national postal questionnaire survey was performed to investigate how cellular pathologists perceive their role in clinical practice and whether there are important differences between different groups of pathologists. Responses were received from 773 pathologists, of whom 167 were trainees. On the basis of responses to 25 attitude statements, it appears that the profession shares a core belief that pathologists are clinicians rather than scientists and sees diagnosis as its main clinical responsibility. However, the role that each pathologist feels clear about differs significantly between pathologists, with a stronger consensus over function, responsibility, and professional image than on the clinical practice of pathology, job satisfaction, and the impact of technological change. Academic activities are a minority interest, although academic pathologists express better job satisfaction and more radical views of professional practice. Young trainees are more likely to work in teaching hospitals, to be female, to have trained outside the UK, and to have had experience in other specialities. They have, however, a more restricted view of the clinical role of pathology than accredited pathologists. Most cellular pathologists see themselves as clinicians with a special role in diagnosis, but how this is interpreted and the extent to which pathologists involve themselves in clinical decision‐making is inconsistent. This professional dilemma should be addressed by research to obtain more systematic knowledge of the clinical impact of cellular pathology and especially the ill‐defined links between diagnosis and clinical decision‐making. Copyright © 2002 John Wiley & Sons, Ltd.
Telepathology in a routine clinical environment: implementation and accuracy of diagnosis by robotic microscopy in a one‐stop breast clinic
Authors: Singh Naveena , Akbar Nuzhat , Sowter Chris , Lea Kevin G. , Wells Clive A. 
Published: October 2002

AbstractThe concept of using telepathology as a way of increasing the efficiency of pathologists is not new. There have been many studies attempting to evaluate the role of telepathology diagnosis, predominantly using transmission of still digital images. This study evaluates the potential value of remote diagnosis using robotic microscopy in the setting of a one‐stop breast clinic. A Zeiss Axiopath telepathology system was used. The aim was to identify deficiencies in software and theminimum specifications for the computer hardware and network capability needed for reproducible pathological diagnosis with a view to developing a system that can preclude the need for an on‐site pathologist. Forty‐seven fine needle aspiration smears were diagnosed simultaneously by a pathologist in the breast clinic and by a different pathologist operating a robotic microscope situated in the clinic in a different wing of the hospital from the pathology department. The diagnoses, the time taken for clinic and remote diagnosis, and difficulties in using the system were recorded. Absolute correlation was achieved in 80.9% of cases. There was one false‐positive diagnosis of cancer and no false negatives. The mean time taken for diagnosis per case was 2.39 min in clinic and 10.81 min by remote control robotic microscopy. However, as the pathologist did not have to leave the department, remote diagnosis was overall more economical of pathologists' time. Image quality was generally found to be good and not an obstacle to diagnosis. There were operational and technical problems that made remote diagnosis tedious and lengthy. Although at present the system is not capable of replacing an on‐site pathologist, the results were encouraging and suggest that remote control remote diagnosis has the potential to increase the efficiency of pathologists. Copyright © 2002 John Wiley & Sons, Ltd.
Gastrointestinal stem cells
Authors: Brittan Mairi , Wright Nicholas A. 
Published: October 2002

AbstractTurnover of the epithelial cell lineages within the gastrointestinal tract is a constant process, occurring every 2–7 days under normal homeostasis and increasing after damage. This process is regulated by multipotent stem cells, which give rise to all gastrointestinal epithelial cell lineages and can regenerate whole intestinal crypts and gastric glands. The stem cells of the gastrointestinal tract are as yet undefined, although it is generally agreed that they are located within a ‘niche’ in the intestinal crypts and gastric glands. Studies of allophenic tetraparental chimeric mice and targeted stem cell mutations suggest that a single stem cell undergoes asymmetrical division to produce an identical daughter cell, and thus replicate itself, and a committed progenitor cell which further differentiates into an adult epithelial cell type. The discovery of stem cell plasticity in many tissues, including the ability of transplanted bone marrow to transdifferentiate into intestinal subepithelial myofibroblasts, provides a potential use of bone marrow cells to deliver therapeutic genes to damaged tissues, for example, in treatment of mesenchymal diseases in the gastrointestinal tract, such as fibrosis and Crohn's disease. Studies are beginning to identify the molecular pathways that regulate stem cell proliferation and differentiation into adult gastrointestinal cell lineages, such as the Wnt and Notch/Delta signalling pathways, and the importance of mesenchymal–epithelial interactions in normal gastrointestinal epithelium and in development and disease. Copyright © 2002 John Wiley & Sons, Ltd.
In vitro model for the study of necrosis and apoptosis in native cartilage
Authors: Grogan Shawn Patrick , Aklin Balz , Frenz Martin , Brunner Thomas , Schaffner Thomas , Mainil‐Varlet Pierre 
Published: October 2002

AbstractApoptosis plays a role in everything from early development to ageing and in a host of disease states. Studying this important process in the in vivo state is critical, to understand its varied role and to open further avenues of therapeutic intervention. The present paper presents an ex vivo bovine articular cartilage model to study apoptotic and necrotic processes following acute injury. Ex vivo bovine articular cartilage was assessed 1, 3 and 6 days following holmium : YAG laser treatment (780 mJ). Markers to visualize cell viability, caspase‐3 activity, changes in mitochondrial membrane potential and the degree of DNA fragmentation (TUNEL assay) were used alone or in various combinations. Standard histology and transmission electron microscopy (TEM) were also performed for a more comprehensive assessment. A significant progression (p < 0.05) of ethidium/caspase‐3‐positive signal depth at day 3 preceded a significant increase (p < 0.05) in TUNEL signal depth by day 6. The mitochondrial matrix marker CMXRos was shown to provide an alternative to calcein‐AM for assessing cell viability. The identification of chondrocyte apoptosis morphology by TEM was not conclusive. Nevertheless, TEM revealed that cells which were clearly necrotic also stained positively for TUNEL, thus indicating the risk of using TUNEL alone for the assessment of apoptosis. The model described here allows the rapid, spatial and temporal determination of cell viability and of apoptotic and necrotic processes in whole‐tissue specimens after acute injury, and permits study of the balance between these events. The assessment of healthy and diseased cartilage and of the effects of surgical, pharmaceutical or in vitro intervention are immediate applications of these protocols. Moreover, this model may be useful for the study of key mechanisms involved in apoptosis or for the establishment of other markers of apoptosis. Copyright © 2002 John Wiley & Sons, Ltd.
Neural stem cells
Authors: Kennea Nigel L. , Mehmet Huseyin 
Published: October 2002

AbstractNeural stem cells (NSCs) have the ability to self‐renew, and are capable of differentiating into neurones, astrocytes and oligodendrocytes. Such cells have been isolated from the developing brain and more recently from the adult central nervous system. This review aims to provide an overview of the current research in this evolving area. There is now increasing knowledge of the factors controlling the division and differentiation of NSCs during normal brain development. In addition, the cues for differentiation in vitro, and the possibility of transdifferentiation are reviewed. The discovery of these cells in the adult brain has encouraged research into their role during neurogenesis in the normal mature brain and after injury. Lastly other sources of neural precursors are discussed, and the potential for stem cells to be used in cell replacement therapy for brain injury or degenerative brain diseases with a particular emphasis on cerebral ischaemia and Parkinson's disease. Copyright © 2002 John Wiley & Sons, Ltd.
Photoinitiated alternating copolymerization of vinyl ethers with chlorotrifluoroethylene
Authors: Gaboyard Manuel , Hervaud Yves , Boutevin Bernard 
Published: October 2002

AbstractThe photoinitiated copolymerization of chlorotrifluoroethylene (CTFE) with several vinyl ethers [ethyl vinyl ether (EVE), 2‐chloroethyl vinyl ether (CEVE), cyclohexyl vinyl ether (CHVE), 4‐hydroxybutyl vinyl ether (HBVE)] was studied. CTFE is an acceptor monomer (e ∼ 1.5) whereas vinyl ethers are donor monomers (e ∼ −1.5), and therefore their copolymerization led to alternating copolymers, as indicated by elementary analysis. The equilibrium constant (KF) of the charge‐transfer complex formation (CTC) was determined by 19F NMR spectroscopy. Under our experimental conditions, KF was low for CHVE/CTFE and HBVE/CTFE systems, 0.058 and 0.013 l mol−1 respectively. It can be assumed that the copolymerization involves the free monomers rather than propagation via the donor–acceptor complex. The alternating structure arises from the great difference in polarity between the two types of monomers. Several functional copolymers were prepared in good yield and with molecular weight close to 15 000 g mol−1.© 2002 Society of Chemical Industry
Morphologies of polybutylacrylate/poly(styrene‐co‐methyl methacrylate) latex prepared by starved emulsion polymerization Part I. Thermodynamics equilibrium morphology
Authors: Huo Dongxia , Liu Dazhuang 
Published: October 2002

AbstractHeterogeneous latexes were prepared by a semicontinuous seeded emulsion polymerization process under monomer starved conditions at 80 °C using potassium persulfate as the initiator and sodium dodecyl sulfate as the emulsifier. Poly(butyl acrylate) latexes were used as seeds. The second‐stage polymer was poly(styrene‐co‐methyl methacrylate). By varying the amounts of methyl methacrylate (MMA) in the second‐stage copolymer, the polarity of the copolymer phase could be controlled. Phase separation towards the thermodynamic equilibrium morphology was accelerated either by ageing the composite latex at 80 °C or by adding a chain‐transfer agent during polymerization. The morphologies of the latex particles were examined by transmission electron microscopy (TEM). The morphology distributions of latex particles were described by a statistical method. It was found that the latex particles displayed different equilibrium morphologies depending on the composition of the second‐stage copolymers. This series of equilibrium morphologies of [poly(butyl acrylate)/poly(styrene‐co‐methyl methacrylate)] (PBA/P(St‐co‐MMA)) system provides experimental verification for quantitative simulation. Under limiting conditions, the equilibrium morphologies of PBA/P(St‐co‐MMA) were predicted according to the minimum surface free energy change principle. The particle morphology observed by TEM was in good agreement with the predictions of the thermodynamic model. Therefore, the morphology theory for homopolymer/homopolymer composite systems was extended to homopolymer/copolymer systems.© 2002 Society of Chemical Industry
The influence of parental and peer attachment on college students' academic achievement
Authors: Fass Michael E. , Tubman Jonathan G. 
Published: October 2002

AbstractThis study examined relations among attachment to parents and peers, cognitive ability, psychosocial functioning variables, and academic achievement in a multiethnic sample of college students (n = 357). A small subgroup (14.8%) of students reported low levels of attachment to both parents and peers. Significant positive correlations were documented between parent and peer attachment and several indices of psychosocial competence. Results from hierarchical multiple regression analyses revealed that indices of cognitive ability were significant predictors of college students' grade point averages, while broader measures of functioning in early adulthood (attachment, intellectual ability, self‐esteem) were significant predictors of scholastic competence. Results suggest that perceived attachment to both parents and peers is a component of wider patterns of social competence and adjustment that may function as protective or compensatory factors during key transitions in young adulthood, such as participation in college, and with its attendant demands for academic achievement. © 2002 Wiley Periodicals, Inc.
Adolescents' perceptions of their fathers' involvement: Significance to school attitudes
Authors: Flouri Eirini , Buchanan Ann , Bream Victoria 
Published: October 2002

AbstractBased on data from 2,722 British adolescents aged 14–18 years, this study explored whether perceived father involvement can be associated with school attitudes even after controlling for perceived mother involvement. Multiple regression analysis showed that both father involvement and mother involvement contributed significantly and independently to positive school attitudes. Furthermore, the association between father involvement and school attitudes was the same for sons and daughters. We did not find evidence to support the notion that being in a non‐intact family weakens the association between perceived father involvement and school attitudes. Finally, there was no evidence suggesting that the impact of perceived father involvement on school attitudes depends on the level of perceived mother involvement. © 2002, Wiley Periodicals, Inc.
Exploring the re‐evaluated interpretation of hydrophobicity to explain rates of Diels–Alder reactions in aqueous salt solutions
Authors: Kumar Anil , Deshpande Suvarna S. 
Published: October 2002

AbstractThe recently proposed correlation between hydrophobicity and internal pressure offers quantitative support to our understanding on the rate enhancement of Diels–Alder reactions in water and its salt solutions. Copyright © 2002 John Wiley & Sons, Ltd.
Substituent effects in solvolysis of 1,1‐diphenylethyl p‐nitrobenzoates. Symmetrically disubstituted and monosubstituted systems
Authors: Fujio Mizue , Uddin Md. Khabir , Kim Hyun‐Joong , Tsuno Yuho 
Published: October 2002

AbstractThe rates of solvolysis of 1,1‐diarylethyl p‐nitrobenzoates and chlorides were determined conductimetrically at 25 °C in 80% (v/v) aqueous acetone. Applying the Yukawa–Tsuno (Y–T) equation, the symmetrical (X = Y) subseries gave a precise additivity relationship for the whole substituent range with a ρsym value of −3.78 and an rsym value of 0.77. While any Y subsets gave statistically less reliable Y–T correlations, the apparent ρ value changed significantly depending on the fixed Y substituents; the ρ value decreases with the more electron‐donating fixed substituents Y, which is compatible with the Hammond shift of the transition state coordinate. Nevertheless, the concave correlations of the More O'Ferrall non‐linearity relationship for any Y subsets are not in line with what is expected from the reactivity–selectivity relationship suggesting an anti‐Hammond shift of transition state. However, we found a precise extended Brønsted relationship between the pK values of 1,1‐diarylethylenes and solvolysis rate process with a constant slope of α = 1.03 ± 0.03. This is direct evidence indicating that there is no significant shift of the transition‐state coordinate over the whole range of substituent change. Copyright © 2002 John Wiley & Sons, Ltd.
Solvolysis of chiral cyclohexylidenemethyl triflate. Evidence against a primary vinyl cation intermediate
Authors: Fujita Morifumi , Yamamoto Akiyo , Sugimura Takashi , Okuyama Tadashi 
Published: October 2002

AbstractSolvolysis of (R)‐4‐methylcyclohexylidenemethyl triflate (6) was examined at 140 °C in various aqueous methanol and some other alcoholic solvents. The main product was (R)‐4‐methylcycloheptanone that maintains the stereochemical purity of 6, with accompanying 4‐methylcyclohexanecarbaldehyde. In the presence of bromide ion, the bromide substitution product was also obtained, mostly with inversion of configuration. It is concluded that the solvolysis does not involve the formation of the primary vinyl cation but proceeds via σ‐bond participation to form the rearranged cycloheptenyl cation as an intermediate. Copyright © 2002 John Wiley & Sons, Ltd.
Photochromism of dihydroindolizines. Part II—Synthesis and photophysical properties of new photochromic IR‐sensitive photoswitchable substituted fluorene‐9′‐styrylquinolinedihydroindolizines
Authors: Ahmed Saleh Abdel‐Mgeed 
Published: October 2002

AbstractTwenty‐nine new photochromic 2,4,7‐substituted fluorene‐9′‐styrylquinolinedihydroindolizines (DHIs) 4a–χ were prepared in 45–75% yield via nucleophilic addition of 4‐styrylquinolines 2a–k to substituted spirocyclopropenes 1a–c. The absorption maxima (λmax) of the colored betaines 3a–χ were detected by flash photolysis measurements. All betaines 3a–χ showed two absorption maxima, one in the visible region (450–525 nm) and another in the IR region (825–950 nm). Absorption spectra of betaines 3a–χ were also recorded at low temperature (77 K) by FT‐UV–Vis–near‐IR spectroscopy. The kinetics of the fast cyclizing process of betaines 3a–χ to DHIs 4a–χ were studied by millisecond flash photolysis and were found to take place in the millisecond range (35–310 ms in dichloromethane solution and 50–425 ms in methanol solution). A transient lifetime (ca 1 ms), measured using laser flash photolysis, was attributed to the transformation of (Z) to (E)‐betaines 3. Large solvatochromic effects on the absorption maxima (λmax) and a substantial increase in the half‐lives (t1/2) with solvent polarity of betaines­3a–χ were also observed. Copyright © 2002 John Wiley & Sons, Ltd.
Solvent‐dependent fluorescence of donor‐substituted (E)‐1,2‐bis(stilbenyl‐1,3,4‐oxadiazolyl)ethenes
Authors: Detert Heiner , Sugiono Erli , Kruse Gabriele 
Published: October 2002

AbstractThe Huisgen reaction of aryltetrazoles and fumaryl chloride leads to symmetrically aryl‐substituted 1,2‐bis(1,3,4‐oxadiazolyl)ethenes. Molecules with extended conjugated systems are accessible using stilbenyltetrazoles or higher homologues. The substitution with solubility‐permitting alkoxy side‐chains results in molecules of C2h symmetry, consisting of a central electron‐accepting segment and two terminal electron density‐releasing units. The solvatochromism of the absorption spectra is negligible, while in the emission spectra a strong positive solvatochromism connected with a dramatic decrease of the quantum yield is observed, indicating intramolecular charge transfer. The influences of different alkoxy substitution patterns on the luminescence properties are discussed. Copyright © 2002 John Wiley & Sons, Ltd.
β‐Butyrolactone polymerization initiated with tetrabutylammonium carboxylates: A novel approach to biomimetic polyester synthesis
Authors: Kurcok Piotr , Śmiga Monika , Jedliński Zbigniew 
Published: October 2002

AbstractThe anionic ring‐opening polymerizations of (R,S)‐β‐butyrolactone and (S)‐β‐butyrolactone initiated with tetrabutylammonium salts of carboxylic acids as initiators were investigated. Poly[(R,S)‐3‐hydroxybutyrate] and poly[(R)‐3‐hydroxybutyrate], with relatively high molecular weights (170,000 and 35,000, respectively) and low molecular weight distributions, were synthesized. Moreover, biomimetic poly(3‐hydroxybutyrate)s with well‐defined microstructures and predictable iso‐dyad contents were obtained. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2184–2189, 2002
Relation between the reactivities of vinyl monomers in ionic polymerizations and their 1H NMR spectra
Authors: Hatada Koichi , Kitayama Tatsuki , Nishiura Takafumi , Shibuya Wataru 
Published: October 2002

Abstract1H NMR chemical shifts of the protons in the vinyl groups of monomers are correlated with their reactivities in anionic, coordinated anionic, and cationic polymerizations. The relative reactivities of styrenes in anionic addition reactions with living polystyrene increase linearly with the chemical shift of the proton trans to the substituent (δH1). Only the plot for 2,4,6‐trimethylstyrene deviates very much from the linear relation because of the large steric hindrance. The relative reactivities of methacrylates in anionic copolymerizations increase with increasing chemical shifts of protons attached to the β‐carbon of methacrylates. In cationic polymerizations of styrenes, the relative reactivities decrease with increasing δH1. The relative reactivities in coordinated anionic polymerizations with Ti‐containing Ziegler initiators show a typical feature of cationic polymerization, and those with V‐containing initiators show a typical feature of anionic polymerization, indicating the importance of the coordination process in the propagation reaction with Ti‐containing initiator systems. From the results, it can be concluded that the chemical shifts of the protons attached to the β‐carbon of vinyl monomers can be used as a practical measure of the reactivity of vinyl monomers in ionic polymerizations and also as a tool for understanding the mechanism of polymerization. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2134–2147, 2002
Poly(ethylene terephthalate) copolymers containing nitroterephthalic units. III. Methanolytic degradation
Authors: Kint Darwin P. R. , Martinez de Ilarduya Antxon , Bou Jordi J. , Muñoz‐Guerra Sebastián 
Published: October 2002

AbstractThe methanolytic degradation of poly(ethylene terephthalate) (PET) copolymers containing nitroterephthalic units was investigated. Random poly(ethylene terephthalate‐co‐nitroterephthalate) copolyesters (PETNT) containing 15 and 30 mol % nitrated units were prepared from ethylene glycol and a mixture of dimethyl terephthalate and dimethyl nitroterephthalate. A detailed study of the influence of the nitro group on the methanolytic degradation rate of the nitrated bis(2‐hydroxyethyl) nitroterephthalate (BHENT) model compound in comparison with the nonnitrated bis(2‐hydroxyethyl) terephthalate (BHET) model compound was carried out. The kinetics of the methanolysis of BHENT and BHET were evaluated with high‐performance liquid chromatography and 1H NMR spectroscopy. BHENT appeared to be much more reactive than BHET. The methanolytic degradation of PET and PETNT copolyesters at 80 °C was followed by changes in the weight and viscosity, gel permeation chromatography, differential scanning calorimetry, scanning electron microscopy, and 1H and 13C NMR spectroscopy. The copolyesters degraded faster than PET, and the degradation increased with the content of nitrated units and occurred preferentially by cleavage of the ester groups placed at the meta position of the nitro group in the nitrated units. For both PET and PETNT copolyesters, an increase in crystallinity accompanied methanolysis. A surface degradation mechanism entailing solubilization of the fragmented polymer and consequent loss of mass was found to operate in the methanolysis of the copolyesters. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2276–2285, 2002