bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polyaniline and its modification for electroresponsive material under applied electric fields
Authors: Cho M. S. , Kim J. W. , Choi H. J. , Jhon M. S. 
Published: January 2005

AbstractPolyaniline (PANI) and its various copolymers were synthesized using different monomers such as o‐methyl‐, o‐methoxy‐, o‐ethyl‐, o‐ethoxyaniline and sodium diphenylamine sulfonate by the chemical oxidation polymerization as air‐stable organic conducting polymers, and adopted as one of the most potential materials of electrorheological (ER) fluids, especially for the anhydrous system. A relatively low density, a controllable conductivity, and thermal stability are advantages of the PANI based ER system compared with other ER materials. An FT‐IR analysis was adopted to confirm their synthesis and a scanning electron microscopy (SEM) analysis indicated the shape of PANI derivatives was irregular. The effect of functional group of PANI on electric and electroresponsive properties of poly(aniline‐co‐ethoxyaniline) (COPA) particles were examined. A universal scaling equation of the yield stress was applied to these ER fluids and it was found that all data were collapsed successfully onto a single curve regardless of monomer type of the polyaniline synthesized. Copyright © 2005 John Wiley & Sons, Ltd.
Reversible control of micellization induced by hydrogen bond crosslinking for a nonamphiphilic diblock copolymer with an α,ω‐diamine
Authors: Yoshida Eri , Ohta Masayo , Terada Yoshikazu 
Published: January 2005

AbstractThe micelle formation in a non‐selective solvent has great advantages in molecular designing. It has already been revealed that a poly(vinylphenol)‐block‐polystyrene diblock copolymer (PVPh‐b‐PSt) formed micelles in the presence of α,ω‐diamine in 1,4‐dioxane, a non‐selective solvent through hydrogen bond crosslinking. In this article it is reported that the dissociation‐reconstruction of the PVPh‐b‐PSt micelles with 1,4‐butanediamine (BDA) is reversibly controlled by the variation in temperature, the copolymer concentration, and the diamine concentration. Light scattering studies demonstrated that the micellization of PVPh‐b‐PSt with Mn(PVPh‐b‐PSt) of 10K‐b‐120K occurred at a higher BDA concentration and produced micelles with a lower aggregation number as the temperature increased. The micelles were thermally unstable and dissociated into unimers by increasing the temperature, however, the micelles were completely reconstructed by decreasing the temperature. This dissociation‐reconstruction of the micelles was perfectly controlled by the variation in temperature. An increase in the BDA concentration prevented the dissociation of the micelles but promoted the reconstruction. The increase in the BDA concentration causes an increase in the crosslinking points for hydrogen bonding in the cores of the micelles, thus preventing the dissociation of the micelles by the strong hydrogen bond crosslinking. Copyright © 2005 John Wiley & Sons, Ltd.
Recent developments in polymeric phase change materials for energy storage: poly(ethylene oxide)/stearic acid blends
Authors: Pielichowski Krzysztof , Flejtuch Kinga 
Published: January 2005

AbstractThe thermal behavior of a series of poly(ethylene oxide) (PEO)/stearic acid blends was investigated by means of differential scanning calorimetry (DSC), modulated temperature DSC, Fourier transform infrared spectroscopy (FT‐IR) and scanning electron microscopy (SEM) for application as thermal energy storage materials. It has been found that PEO/stearic acid blends are efficient polymer‐based phase change materials that can be applied in the temperature range 55.7–75.2°C with the enthalpy of phase transition values in the range of 202.8–252.3 J/g. The PEO/stearic acid blend (1:3 w/w) exhibits a senergistic effect—its value of enthalpy of melting and crystallization is higher than those of pure components. The origin of this promising effect was investigated by FT‐IR and SEM techniques to ascertain the influence of hydrogen bonds on the sample's supramolecular morphology. Copyright © 2005 John Wiley & Sons, Ltd.
Asymmetric PS‐block‐(PS‐co‐PB)‐block‐PS block copolymers: morphology and deformation behavior of star block copolymer/PS blends
Authors: Adhikari R. , Buschnakowski M. , Lebek W. , Godehardt R. , Michler G. H. , Calleja F. J. Baltá , Knoll K. 
Published: January 2005

AbstractThe morphology and deformation behavior of blends comprising an asymmetric styrene/butadiene star block copolymer and polystyrene homopolymer (hPS) were investigated by means of transmission electron microscopy (TEM) and uniaxial tensile testing. The hPS samples used had a wide range of molecular weights. In spite of the high polystyrene (PS) content, the star block copolymer exhibited a morphology consisting apparently of a rubbery matrix, attributable to its asymmetric architecture and presence of polystyrene/polybutadiene random copolymer (PS‐co‐PB) as soft rubbery blocks. In the blends, depending on the molecular weight and modality of the added hPS and on the composition of the mixtures, different morphologies (ranging from microphase‐separated and macrophase‐separated ones to a combination of both of them) were observed. Consequently, it was possible to tailor the tensile mechanical properties based on the nature of the nanoscopic morphology of the star block copolymer/PS blends. Copyright © 2005 John Wiley & Sons, Ltd.
Morphology and micromechanical properties of ethylene/1‐octene copolymers and their blends with high density polyethylene
Authors: Adhikari R. , Godehardt R. , Lebek W. , Frangov S. , Michler G. H. , Radusch H.‐J. , Calleja F. J. Baltá 
Published: January 2005

AbstractThe relationship between morphology and deformation behavior of selected ethylene/1‐octene copolymers (EOCs) and their blends with high density polyethylene (HDPE) was investigated. The copolymers showed, depending on the 1‐octene content, different morphologies ranging from lamellar to worm‐like crystalline domains. The binary HDPE/EOC blends studied, which showed well phase‐separated structures consistent with individual melting and crystallization behavior of the blend components, were characterized by a wide range of mechanical and micromechanical properties. The study of strain induced structural changes in an HDPE/EOC blend revealed that at large strains, the extensive stretching of the soft EOC phase is accompanied by rotation of lamellar stack along the strain axis and subsequent fragmentation of the crystals forming beaded‐string‐like structures. A significant depression in microhardness was observed in the copolymers. In their blends with HDPE, a deviation in microhardness behavior from the additivity law was observed. Copyright © 2005 John Wiley & Sons, Ltd.
Effect of gamma irradiation on HDPE/HA (80:20) composites
Authors: Albano C. , Karam A. , González G. , Domínguez N. , Sánchez Y. , Manzo F. , Guzmán‐García C. 
Published: January 2005

AbstractEffect of gamma irradiation on high density polyethylene/hydroxyapatite (HDPE/HA) composites prepared by solution was studied. Melt flow index (MFI) showed a strong increase with radiation due to some decalin remnant. The evaluation of the mechanical behavior showed an increase in the Young's modulus and resistance at break values attributed to the HA addition. Elongation at break decrease strongly. Radiation did not produce any significant changes on crystallization temperatures. Crystallinity of the polymer decreases when HA is added. The activation energy values allowed for the estimation of the optimum radiation dose. Copyright © 2005 John Wiley & Sons, Ltd.
Oncogene lineages of human papillomavirus type 16 E6, E7 and E5 in preinvasive and invasive cervical squamous cell carcinoma
Authors: Hu Xinrong , Pang Tianyun , Guo Zhongmin , Pontén Jan , Nistér Monica , Bernard Afink Gijs 
Published: January 2005

AbstractHuman papillomavirus (HPV)16 accounts for about 60% of the HPV infections in invasive cervical cancer (ICC). There are many sequence variations within HPV16, some of which have been associated with different biological properties, although no definite correlations have yet been established. However, the definition ‘variant’ has been a source of confusion in research and diagnosis, since it is based on all sequence deviations from a randomly selected prototype. This study has sequenced the HPV16 oncogenes E6, E7 and E5 from 61 Swedish cases with cervical intraepithelial neoplasia grade III (CIN III) or ICC. Clustering the sequence variations at the three common sites of variation (nucleotide 350 in E6, which has previously been associated with the progression from CIN III to ICC, and nucleotides 3979 and 4042 in E5) resulted in the distinction of three major oncogene lineages encompassing more than 95% of the cases, and two minor oncogene lineages. Simple comparison of the distribution of the individual variations or oncogene lineages between CIN III and ICC showed no significant difference, but the number of variations in addition to the three common ones was significantly higher in ICC. This novel classification scheme, based on the variations in the E6, E7 and E5 region, is considered to be a major improvement over the classical ‘prototype‐variant’ classification, and can help to clarify the interpretation of HPV sequence data in relation to the progression of cervical cancer. Copyright © 2001 John Wiley & Sons, Ltd.
p53 over‐expression identifies a subset of nodal peripheral T‐cell lymphomas with a distinctive biological profile and poor clinical outcome
Authors: Pescarmona Edoardo , Pignoloni Patrizia , Puopolo Maria , Martelli Maurizio , Addesso Maria , Guglielmi Cesare , Baroni Carlo D. 
Published: January 2005

AbstractPeripheral T‐cell lymphomas (PTCL) are usually characterized by aggressive clinical behaviour and poor clinical outcome, but their biological background has not been extensively investigated to date, due to their low incidence, about 10% of all non‐Hodgkin's lymphoma cases in Western countries, and also to the paucity of specific molecular‐genetic abnormalities. Neverthless, there is increasing biological and clinical evidence that primary nodal PTCL should be considered separately from extra‐nodal cases, but little is known about biological factors of possible clinical and prognostic impact. This immunohistochemical study has analysed the expression of p53, Mdm2, p21WAF1, BCL‐2 and p‐glycoprotein (MDR‐1 gene product) in a series of 45 cases of nodal peripheral T‐cell lymphomas (PTCL) with ‘high‐grade’ histology. The immunohistochemical findings were then correlated with proliferative activity and clinical outcome. p53 was over‐expressed in 13 cases (28.9%). p53 positive cases showed significantly higher proliferative activity (p<0.01), more frequent expression of Bcl‐2 (p<0.01) and less frequent expression of p21WAF1 than p53 negative cases. Mdm2 and p‐glycoprotein were expressed in 4/13 (30.8%) and 8/13 (61.5%) p53 positive cases respectively, and in none (0%) of the p53 negative cases (p<0.01). Analysis of the survival curves showed that p53 positive cases were associated with a significantly poorer clinical outcome than p53 negative cases, in terms of both overall survival (p=0.0032) and event‐free survival (p=0.0004). Furthermore, multivariate analysis showed that p53 expression was the most important independent prognostic variable. These findings indicate that p53 over‐expression identifies a subset of nodal PTCL cases with a distinctive biological profile (higher proliferative activity, less frequent expression of p21WAF1 and more frequent expression of Bcl‐2, Mdm2 and p‐glycoprotein than p53 negative cases) and poor clinical outcome. The immunohistochemical analysis of p53 expression is a simple, rapid and low‐cost method which may provide information of potential clinical and prognostic value in nodal peripheral T‐cell lymphomas. Copyright © 2001 John Wiley & Sons, Ltd.
Decline in the expression of the serine proteinase inhibitor maspin is associated with tumour progression in ductal carcinomas of the breast
Authors: Maass Nicolai , Teffner Martin , Rösel Frank , Pawaresch Reza , Jonat Walter , Nagasaki Koichi , Rudolph Pierre 
Published: January 2005

AbstractMaspin is an inhibitor of serine proteinases with tumour suppressor activity. Its expression appears to be reduced in advanced stages of breast cancer. A large series of archival breast tissue specimens has been examined, including normal glands (n=7), fibrocystic change (n=22), ductal carcinoma in situ (DCIS, n=12), infiltrating carcinomas (n=128) and their lymph node metastases (n=65), using a specific monoclonal antibody. Myoepithelium invariably showed strong maspin expression. In epithelial cells, the strongest expression was found in normal breast and fibrocystic change. A significant stepwise decrease in maspin expression (p<0.0001) occurred in the sequence DCIS – invasive cancer – lymph node metastasis. However, a subset of infiltrating carcinomas showed strong maspin expression, significantly associated with a lower rate of lymph node metastasis at the time of diagnosis (p<0.01). This was independent of tumour size and grade. The in vivo observations presented here are in keeping with data obtained in prior in vitro experiments. Maspin emerges as an indicator of tumour progression and metastatic potential, and might be exploited to predict breast cancer prognosis. According to in vitro data, its tumour suppressor activity is likely to involve both the modulation of cell motility/invasiveness and the inhibition of angiogenesis. Copyright © 2001 John Wiley & Sons, Ltd.
Heavy metals of relevance to human health induce genomic instability
Authors: Coen Natasha , Mothersill Carmel , Kadhim Munira , Wright E. G. 
Published: January 2005

AbstractHeavy metals used in medical prostheses or present in water supplies or tobacco can build up in tissues and blood and are well known to produce toxic effects. Normally, legislative controls on the levels of these substances are determined by reference to the acute toxicity data. This paper shows that cadmium and nickel can produce delayed effects in human cells in vitro, which are characteristic of genomic instability. The effects occur even at levels where no acute toxic effects can be demonstrated. Genomic instability can be demonstrated by persistent induction of cytogenetic abnormalities and delayed cell death in progeny of cells many generations after exposure. Formerly, this syndrome has only been definitively proven to occur following irradiation, but in these experiments cell populations exposed for only 1 or 24 hours were expanded over several months, involving eight passages, and the yield of chromosomal aberrations and cell loss due to lethal mutations did not decrease. The consequences of this genomic instability are not yet known but it is possible that many of the systemic symptoms associated with exposure to low concentrations of these metals could involve delayed expression of cellular damage. It is also clear that these effects cannot be predicted from acute toxicity data. Copyright © 2001 John Wiley & Sons, Ltd.
Differential expression of the chromosome 11 mucin genes in colorectal cancer
Authors: Sylvester Paul A. , Myerscough Neil , Warren Bryan F. , Carlstedt Ingemar , Corfield Anthony P. , Durdey Paul , Thomas Michael G. 
Published: January 2005

AbstractThe four secretory mucin genes clustered on chromosome 11, MUC2, MUC5AC, MUC5B and MUC6, were screened in 37 patients with cancers in the left hemi‐colon or rectum and 10 normal rectal controls. The mucin genes were detected by in situ hybridization using oligonucleotide probes to the variable number tandem repeat (VNTR) sequences, while the proteins were stained with non‐VNTR (MUC2, MUC5AC and MUC5B) or VNTR (MUC6) antibodies. Low levels of MUC2 mRNA were detected in non‐mucinous adenocarcinomas (5/27) while a higher proportion of mucinous carcinomas (4/9) was positive. All 25 cases of adjacent normal tissue expressed MUC2 mRNA. No transcripts for MUC5AC, MUC5B or MUC 6 were detected in any of these specimens. MUC2 protein product was detected immunohistochemically in 34/36 carcinoma specimens, with no change from normal controls. There was de novo expression of MUC5AC in 23/36 carcinomas. No MUC5B or MUC6 protein was detected. No difference in MUC2 and MUC5AC protein was found between mucinous and non‐mucinous carcinomas. The level of MUC2 was increased in moderately differentiated cancers compared with normal controls and decreased in the poorly differentiated group. Decreased MUC2 was found in poorly differentiated compared with moderately differentiated tumours. More MUC5AC protein was detected in well and moderately differentiated tumours than in poorly differentiated tumours and in all tumours relative to controls. The pattern of MUC2 staining in cancers was different from control tissue, with strong staining in the perinuclear region and none in goblet cell vesicles. MUC5AC staining was mainly detected in the cytoplasm. Poor detection of MUC2 and MUC5AC mRNA and associated strong staining for the total protein suggests altered biosynthesis and processing, leading to the characteristic subcellular distribution. Hence, change in the synthesis of MUC2 and the de novo appearance of MUC5AC in colorectal carcinomas may be significant events in the adenoma‐carcinoma sequence, with possible implications for tumour prognosis. Copyright © 2001 John Wiley & Sons, Ltd.
Molecular classification of breast cancer patients by gene expression profiling*
Authors: Ahr André , Holtrich Uwe , Solbach Christine , Scharl Anton , Strebhardt Klaus , Karn Thomas , Kaufmann Manfred 
Published: January 2005

AbstractFor many tumuors, pathological subclasses exist which have to be further defined by genetic markers to improve therapy and follow‐up strategies. In this study, cDNA array analyses of breast cancers have been performed to classify tumuors into categories based on expression patterns. Comparing purified normal ductal epithelial cells and corresponding tumour tissues, the expression of only a small fraction of genes was found to be significantly changed. A subset of genes repeatedly found to be differentially expressed in breast cancers was subsequently employed to perform a classification of 82 normal and malignant breast specimens by cluster analysis. This analysis identifies a subgroup of transcriptionally related tumours, designated class A, which can be further subdivided into A1 and A2. Correlation with classical clinicopathological parameters revealed that subgroup A1 was characterized by a high number of node‐positive tumours (14 of 16). In this subgroup there was a disproportionate number of patients who had already developed distant metastases at the time of diagnosis (25% in this subgroup, compared with 5% among the rest of the samples). Taken together, the use of these differentially expressed marker genes in conjunction with sample clustering algorithms provides a novel molecular classification of breast cancer specimens, which facilitates the identification of patients with a higher risk of recurrence. Copyright © 2001 John Wiley & Sons, Ltd.
Cathepsin K – a marker of macrophage differentiation?
Authors: Bühling F. , Reisenauer A. , Gerber A. , Krüger S. , Weber E. , Brömme D. , Roessner A. , Ansorge S. , Welte T. , Röcken Ch. 
Published: January 2005

AbstractCathepsin K is a cysteine protease with high matrix‐degrading activity. Initially, cathepsin K was described as being expressed exclusively by osteoclasts. It was suggested that cathepsin K expression is a specific feature of cells involved in bone remodelling. The aim of this study was to investigate the hypothesis that cathepsin K is expressed not only in bone‐resorbing macrophages, but also more generally in specifically differentiated macrophages, such as epithelioid cells and multinucleated giant cells in soft tissues. Specimens obtained from different organs and anatomical locations of patients suffering from sarcoidosis, tuberculosis, granulomas caused by foreign materials, and sarcoid‐like lesions were investigated for the expression of cathepsins B, K, and L. Immunohistochemistry and in situ hybridization showed cathepsin K in epithelioid cells and multinucleated giant cells irrespective of the pathological condition and anatomical location, but not in normal resident macrophages. By immunoelectron microscopy, cathepsin K was discovered in cytoplasmic granules of multinucleated giant cells. In contrast, cathepsin B and cathepsin L were expressed ubiquitously in CD68‐positive tissue macrophages, epithelioid cells, and multinucleated giant cells. The results demonstrate that cathepsin K, but not cathepsin B or cathepsin L, differentiates specific phenotypes of macrophages independently of the anatomical site. Its enzymatic characteristics, particularly its high matrix‐degrading activity, suggest that cathepsin K‐positive epithelioid cells and multinucleated giant cells are characterized by an enhanced specific proteolytic capability. Copyright © 2001 John Wiley & Sons, Ltd.
Collagen VII expression in glomerular sclerosis
Authors: Onetti Muda Andrea , Ruzzi Laura , Bernardini Silvia , Teti Anna , Faraggiana Tullio 
Published: January 2005

AbstractGlomerular sclerosis is the final stage of a variety of kidney diseases and matrix molecules not normally expressed in the extracellular matrix are synthesized and accumulate during the sclerotic process. Collagen type VII is the major component of the anchoring fibrils at the dermal–epidermal junction, but it is usually not present in normal glomeruli. The aim of this study was to investigate whether this type of fibrillary collagen, different from types I and III, is expressed in chronically diseased glomerular extracellular matrix. The presence and distribution of collagen VII have been examined in 50 renal biopsies by indirect immunofluorescence staining, standard electron microscopy, and immuno‐electron microscopy. In selected cases, collagen VII mRNA expression was also measured by RT‐PCR on isolated glomeruli. Cases included focal segmental glomerulosclerosis, minimal change disease, membranous glomerulonephritis, IgA nephropathy, SLE nephritis, diabetic glomerulosclerosis, ischaemic renal disease, extracapillary glomerulonephritis, and end‐stage renal disease. Collagen VII protein and mRNA expression was absent or present in trace amounts in normal kidneys or in disorders with only a mild increase of mesangial matrix, without scarring of the tuft. Maximal expression was evident in the presence of adhesions between the glomerular tuft and Bowman's capsule or fibrous crescents. The results showed that collagen VII is actively synthesized and laid down in areas of glomerular and/or tubular scarring, irrespective of the underlying disease, confirming the de novo expression of fibrillary collagens in diseased renal extracellular matrix. The appearance of an anchoring collagen may be a response to support mechanical stress and it takes part in the process of cell proliferation and tissue repair. Copyright © 2001 John Wiley & Sons, Ltd.