bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of tumor location on breast cancer prognosis
Authors: Kroman Niels , Wohlfahrt Jan , Mouridsen Henning T. , Melbye Mads 
Published: April 2003

AbstractOur objective was to investigate the influence of primary tumor location on breast cancer prognosis. We used a population‐based registry since 1977 that has collected detailed information regarding clinical and histopathological presentation, postoperative therapy and follow‐up status on Danish women with breast cancer. Nodal status and relative risk of dying was estimated according to primary tumor localization in the breast. Overall, 35,319 patients with primary breast cancer were included in the study. After adjustment for prognostic factors, the risk of dying increased significantly (up to 21%) with increasing distance of tumor location from the axilla. This trend was seen both among women with and without spread to the axillary lymph nodes. In conclusion, survival is significantly better for women with a tumor in the upper lateral quadrant than tumors located elsewhere in the breast. Our finding of a similar trend according to distance from the axilla among women with positive axillary lymph nodes who all are allocated to systemic therapy suggests that a better lymph node staging procedure alone is unlikely to eliminate these survival differences. Other reasons for the observed differences should be sought to help improve survival for women with breast cancer. © 2003 Wiley‐Liss, Inc.
Molecular detection of p16 promoter methylation in the serum of recurrent colorectal cancer patients
Authors: Nakayama Hiroshi , Hibi Kenji , Takase Tsunenobu , Yamazaki Taiji , Kasai Yasushi , Ito Katsuki , Akiyama Seiji , Nakao Akimasa 
Published: April 2003

AbstractWe previously proved that p16 promoter methylation present in the tumors of colorectal cancer patients can be detected in the serum of those same patients using methylation‐specific PCR (MSP). To seek the possibility that this technique could be applied to the monitoring of cancer recurrence, we examined the p16 methylation using MSP. We detected tumor DNA in the serum of 31 of 45 (69%) patients with recurrent colorectal cancer. No methylation was found in serum DNA of 50 patients with colorectal cancers whose corresponding tumor DNA had no methylation in p16 promoter. These results suggested that MSP might be a sensitive and useful method to detect recurrent colorectal cancer in serum. © 2003 Wiley‐Liss, Inc.
Fried potatoes and human cancer
Authors: Pelucchi Claudio , Franceschi Silvia , Levi Fabio , Trichopoulos Dimitrios , Bosetti Cristina , Negri Eva , La Vecchia Carlo 
Published: April 2003

AbstractA considerable public concern about cancer risk from acrylamide‐rich foods followed the announcement that high concentrations of acrylamide are found in fried potatoes and potato chips and, more generally, in starch‐containing foods cooked at high temperatures. From a series of hospital‐based case–control studies conducted in Italy and Switzerland between 1991 and 2000, we have analyzed the relation between intake of fried/baked potatoes and cancer risk. The cancer sites considered were oral cavity and pharynx (749 cases, 1,772 controls), esophagus (395 cases, 1,066 controls), larynx (527 cases, 1,297 controls), large bowel (1,225 colon and 728 rectum cases, 4,154 controls), breast (2,569 cases, 2,588 controls) and ovary (1,031 cases, 2,411 controls). All cancer cases were incident and histologically confirmed. Controls were subjects admitted to the same network of hospitals of cases for acute, non‐neoplastic conditions. All the odds ratios (OR) for the highest vs. the lowest tertile of intake ranged between 0.8–1.1. We found no evidence of interaction with age, gender, alcohol and tobacco use. Our data provide reassuring evidence for the lack of an important association between consumption of fried/baked potatoes and cancer risk. © 2003 Wiley‐Liss, Inc.
Leucine‐zipper protein, LDOC1, inhibits NF‐κB activation and sensitizes pancreatic cancer cells to apoptosis
Authors: Nagasaki Koichi , Schem Christian , von Kaisenberg Constantin , Biallek Marco , Rösel Frank , Jonat Walter , Maass Nicolai 
Published: April 2003

AbstractWe have isolated a novel gene, LDOC1, which encodes for a leucine zipper protein that was downregulated in a series of human pancreatic cancer cell lines but was expressed in corresponding normal tissues. We report the initial characterization of LDOC1 as a novel regulator of the transcriptional response mediated by the nuclear factor kappa B (NF‐κB). Transient expression of LDOC1 significantly inhibited the luciferase activity in LDOC1‐negative BxPC‐3 pancreatic cancer cell line transfected with the NF‐κB reporter plasmid, activated with mitogen‐activated protein kinase/ERK kinase kinase‐1 (MEEK). LDOC1, however, does not affect p53, AP1 and CRE‐dependent reporter gene expression. The activation of NF‐κB through ligand‐induced stimulation by tumor necrosis factor‐α (TNF‐α) or phorbol 12‐myristate 13‐acetate (PMA) was also inhibited by transient expression of LDOC1 in a dose dependent manner. To determine the growth effect of LDOC1 expression on cancer cells, BxPC‐3 cells were stably transfected with LDOC1 cDNA. Viability studies demonstrated that TNF‐α or PMA‐induced antiproliferative effects were significantly enhanced by stable transfection of cells with LDOC1. These observations suggest that LDOC1 is a novel regulator of NF‐κB that can affect the PMA or TNF‐α‐mediated pathway to apoptosis through inhibition of NF‐κB activation in BxPC3 pancreatic cancer cells. © 2003 Wiley‐Liss, Inc.
Increased protein expression of DNA methyltransferase (DNMT) 1 is significantly correlated with the malignant potential and poor prognosis of human hepatocellular carcinomas
Authors: Saito Yoshimasa , Kanai Yae , Nakagawa Tohru , Sakamoto Michiie , Saito Hidetsugu , Ishii Hiromasa , Hirohashi Setsuo 
Published: April 2003

AbstractAlteration of DNA methylation is one of the most consistent epigenetic changes in human cancers. DNA methyltransferase (DNMT) 1 is a major enzyme involved in establishing genomic methylation patterns. Most of the studies concerning DNMT1 expression in human cancers have been performed only at the mRNA level. To directly examine DNMT1 protein expression levels during human hepatocarcinogenesis, 16 histologically normal liver tissues, 51 noncancerous liver tissues exhibiting chronic hepatitis or cirrhosis, which are considered to be precancerous conditions, and 53 hepatocellular carcinomas (HCCs) were subjected to immunohistochemic examination. If more than 20% of the cells exhibited nuclear DNMT1 staining, the tissue sample was considered to be DNMT1‐positive. DNMT1 immunoreactivity was observed in 23 (43%) of the HCCs, but in none (0%) of the histologically normal liver or noncancerous liver tissues exhibiting chronic hepatitis or cirrhosis. The incidence of increased DNMT1 protein expression in HCCs correlated significantly with poor tumor differentiation (p = 0.0006) and portal vein involvement (p = 0.0002). Moreover, the recurrence‐free (p = 0.0001) and overall (p < 0.0001) survival rates of patients with HCCs exhibiting increased DNMT1 protein expression were significantly lower than those of patients with HCCs that did not exhibit increased expression. Increased DNMT1 protein expression may play a critical role in the malignant progression of HCCs and be a biologic predictor of both HCC recurrence and a poor prognosis in HCC patients. © 2003 Wiley‐Liss, Inc.
Chords of longest circuits of graphs embedded in torus and Klein bottle
Authors: Li Xuechao , Zhang Cun‐Quan 
Published: April 2003

AbstractThomassen conjectured that every longest circuit of a 3‐connected graph has a chord. It is proved in this paper that every longest circuit of a 4‐connected graph embedded in a torus or Klein bottle has a chord. © 2003 Wiley Periodicals, Inc. J Graph Theory 43: 1–23, 2003
Highly edge‐connected detachments of graphs and digraphs
Authors: Berg Alex R. , Jackson Bill , Jordán Tibor 
Published: April 2003

AbstractLet G = (V,E) be a graph or digraph and r : V → Z+. An r‐detachment of G is a graph H obtained by ‘splitting’ each vertex ν ∈ V into r(ν) vertices. The vertices ν1,…,νr(ν) obtained by splitting ν are called the pieces of ν in H. Every edge uν ∈ E corresponds to an edge of H connecting some piece of u to some piece of ν. Crispin Nash‐Williams 9 gave necessary and sufficient conditions for a graph to have a k‐edge‐connected r‐detachment. He also solved the version where the degrees of all the pieces are specified. In this paper, we solve the same problems for directed graphs. We also give a simple and self‐contained new proof for the undirected result. © 2003 Wiley Periodicals, Inc. J Graph Theory 43: 67–77, 2003
Kinetics of crystallization and a crystal‐crystal transition in poly‐1‐butene
Authors: Boor J. , Mitchell J. C. 
Published: April 2003

AbstractThe formation and melting of the two crystalline modifications of poly‐1‐butene have been studied by the techniques of differential thermal analysis, infrared spectroscopy, dilatometry, and polarizing microscopy. On cooling the melt, modification 2 (Tm = 120–126°C.) appears within minutes. This form is unstable and gradually transforms to modification 1 (Tm = 135–142°C.). A density change of over 4% accompanies this latter transformation. As torsional damping experiments have shown the amorphous content to decrease by only about 5%, the stable modification must be much more dense than the unstable form. The kinetics of the crystallization of modification 2 from the melt were studied primarily dilatometrically at several temperatures. The data generally followed the Avrami equation with n equal to 4. This crystallization shows a high negative temperature coefficient (T1/2 = 380 min. at 110°C. and 2 min. at 90°C.) and becomes too rapid to measure by this technique at lower temperatures. The kinetics of the transformation of modification 2 to modification 1 were followed in infrared spectral, density gradient tube, and dilatometric studies. At room temperature, halftimes ranging from 250 to 1600 min. were observed, depending on the mechanical and thermal history of the sample. The observed discrepancies have been shown to be due, at least in part, to orientation effects. In dilatometric studies of the temperature dependence, the transition rate showed a pronounced maximum in the region of 15°C. Large increases in the torsional modulus and offset yield point of the specimen were observed to accompany the transition.
The dielectric relaxation time spectrum and the corresponding cole‐cole diagram for methylcellulose in water
Authors: Kuhn W. , Moser P. 
Published: April 2003

AbstractFrom a measurement of the dielectric increment of methylcellulose in water, including the frequency dependence of this increment, the dielectric relaxation time spectrum has been determined and represented quantitatively by a formula containing three parameters τor, νAh, and θq, each of which can be obtained from earlier published viscosity and birefringence of flow data. On the basis of this relaxation time spectrum, the Cole‐Cole diagram of the aqueous solution of methylcellulose can be drawn. It is found that this diagram is dissymmetrical, i.e., different in shape from a circle or part of a circle; the circular form of the Cole‐Cole diagram is thus not a general phenomenon, even if it is realized in many cases.
Viscosity of critical mixtures
Authors: Debye P. , Chu B. , Woermann D. 
Published: April 2003

AbstractMeasurements of the viscosity of critical mixtures were extended to high polymer solutions (polystyrene–cyclohexane). An anomaly is found in the temperature coefficient of the viscosity. An empirical expression for the viscosities of critical mixtures as a function of ΔT/Tc, where ΔT = T − Tc, and Tc is the critical temperature, is derived.
Critical opalescence of polystyrene in ethylcyclohexane
Authors: Debye P. , Woermann D. , Chu B. 
Published: April 2003

AbstractThe range of molecular forces and the critical temperature of polystyrene in ethylcyclohexane are calculated from measurements of the angular dependence of critical opalescence. The polystyrene samples have molecular weights ranging from 69,000 to 552,000. The range of molecular forces remains strikingly small and is comparable with values obtained earlier on the system polystyrene–cyclohexane.
A theory for surface elevation in the weissenberg effect
Authors: Middleman Stanley 
Published: April 2003

AbstractA Couette flow generated by a cylinder rotating perpendicular to the free surface of a fluid is considered and the equations of motion are solved to yield an expression for the surface shape in the vicinity of the rod. The fluid model chosen is one for which the shear stress τrθ and the normal stresses Trr and Tee obey the relations

where M, n, a, b, and κ are constants characteristic of the fluid and v is the flow velocity component in the angular direction. The results are found to be in reasonable agreement with previous experimental observations of the Weissenberg effect.
Depolarization of scattered light in solutions of linear and branched polysaccharides
Authors: Rao V. S. R. , Foster Joseph F. 
Published: April 2003

AbstractThe effect of branching on the depolarization of light scattered from polymer solutions has been investigated employing various branched and unbranched polysaccharides. Two dextran fractions of M̄w 71,000 and 131 × 106 were studied in a strong solvent (aqueous KOH) and an indifferent solvent (water). The other polymers, studied in aqueous KOH only, included unfractionated corn amylopectin, the β‐amylase limit dextrin of corn amylopectin, unfractionated corn amylose, and three subfractions of potato amylose (M̄w = 2.4 × 106, 1.14 × 106, and 0.27 × 106). Each polymer system was studied at several concentrations and all components of the scattered light, namely Hu, Vu, Hv, Vv, Hk, and Vh, were measured in each case. In general the results are in agreement with predictions of Krishnan and of Doty. However, certain important deviations from predicted behavior are noted and discussed.
Unsaturation in high impact polystyrene analytical studies
Authors: Crompton T. R. , Reid V. W. 
Published: April 2003

AbstractA method for separating a pure gel and a soluble graft containing fraction from high impact polystyrene is described together with methods for determining the unsaturation of these two fractions and for the determination of unsaturation in polybutadiene rubber and unfractionated high impact polystyrene samples. The methods have been used to show how the rubber distributes between the gel and soluble fractions obtained from high impact polystyrenes prepared by the interpolymerization technique.
Depolarization measurements of polymer solutions in high dilutions. Part I
Authors: Kalpagam V. , Ramakrishna Rao M. 
Published: April 2003

AbstractThe depolarization ratios of unpolarized light, vertically polarized light, and horizontally polarized light at 90° have been measured for polyvinyl acetate solutions at high dilutions with the help of a specially designed differential amplifier. Over the concentration range (0.01–0.25%) studied, the values of ρu and ρv decrease sharply with increasing concentrations up to a concentration of about 0.1% and then the curves flatten out. Depending upon the nature of the solvent, there exists for each polymer—solvent system a critical concentration range above which the anisotropy of the molecules does not later further. This behavior is the same both in the good solvent (methyl ethyl ketone) and the relatively poor solvent (ethyl acetate). The experimentally determined ρh values generally are in agreement with the values calculated from the reciprocity theorem, except where ρh values are greater than one. In the case of ρh values which are greater than unity the difference between the experimentally determined and the calculated values is as high as 70%.
Nitroso fluorocarbon elastomers. Polymerization mechanism
Authors: Crawford G. H. , Rice D. E. , Landrum B. F. 
Published: April 2003

AbstractThe mechanism of copolymerization of fluoronitrosoalkanes with fluoroolefins was investigated. The reaction was not inhibited by water or other common ionic polymerization inhibitors but was greatly affected by free radicals or radical chain transfer agents, indicating a free radical polymerization mechanism. Evidence against initiation by impurities or by homolytic cleavage of the nitroso monomer was obtained. Initial rates of polymerization in solution were determined. The data obtained is consistent with a polymerization mechanism involving initiation by a radical formed through the interaction of the fluoroolefin with the fluoronitrosoalkane which has a significant diradical or triplet state population at the polymerization temperature. The reactivities of various monomers, the formation of low molecular weight product and the structures of the oxazetidine by‐products are discussed in terms of this mechanism.
Particle size distribution in polymer solutions
Authors: Maurer John J. 
Published: April 2003

AbstractLog‐normal particle size distributions in polymer solutions have been measured with the Coulter counter. Qualitative membrane diffusion measurements were performed to substantiate the presence in these solutions of particles in the micron size range. Particle size was found to be dependent upon the thermal history of a polymer solution and upon the shearing forces to which it had been subjected. Further, particle size decreased upon dilution of a polyelectrolyte solution or upon an increase in the salt content. It is concluded that polymeric aggregates are the species being counted. These aggregates apparently originated during the polymerization of the polystyrene or of the styrene maleic anhydride studied. Bimodal distributions were observed in polystyrene solutions and in polystyrene sulfonate (Na+) solutions. The latter bimodal systems were resolved by graphical means, and it was found that the two populations are present in the ratio 65:35. The two distributions have the same dispersions (0.04) and only slightly different means (3.7 versus 4.5 microns). The mechanism of formation of this bimodal system may be that proposed by van der Hoff; namely, that particles are formed consecutively in the micellar and in the aqueous phase of an emulsion polymerization system when the soap concentration is near the critical micelle concentration.
Crystallinity and the structure of celluloses
Authors: Heritage K. J. , Mann J. , Roldan‐Gonzalez L. 
Published: April 2003

AbstractObservations on the x‐ray scattering by ball‐milled cellulose and cellulose derivatives, amorphous oligosaccharides, and Fortisan H are reported and an approximate shape is established for the scattering curve of the noncrystalline component of celluloses. Using this shape measurements have been made of the minimum crystallinity which is consistent with the observed x‐ray diagram of regenerated cellulose.From a comparison of this minimum crystallinity with crystallinity determined by the infrared‐deuteration method, it is concluded that at least 14% of the total material cannot be truly described as either perfectly crystalline or perfectly amorphous. This fraction of material of intermediate order is registered as crystalline by x‐ray diffraction, but infrared spectroscopy suggests that it does not possess the precise molecular configuration characteristic of crystalline material. Support for this view of structure is reported from observations of differences in hydrogen‐bonding in amorphous regions of regenerated and bacterial celluloses. Infrared results show that OH groups which lie in the surface of crystallites are hydrogen‐bonded in a random amorphous manner and it is concluded that the material of intermediate order can be accounted for in terms of chains lying in the surface of crystallites of cross‐section 29 A. × 65 A.
Copolymerization of acrylonitrile and p‐sodium styrene sulfanate
Authors: Izumi Z. , Kiuchi H. , Watanabe M. 
Published: April 2003

AbstractThe copolymerization of acrylonitrile (AN) with sodium p‐styrenesulfonate (SSS) in aqueous solutions (of pH 3 and pH 7) has been investigated. Monomer reactivity ratios at 45°C. for AN and SSS are found to be r1 = 0.10 ± 0.02, r2 = 1.20 ± 0.10 at pH 3 and r1 = 0.05 ± 0.01, r2 = 1.40 ± 0.04 at pH 7, from which Price Q and e values for SSS of 0.76 and −0.26 at pH 3 and of 1.25 and −0.43 at pH 7 are calculated. Initial rates of copolymerization at 45°C. with ammonium persulfate (APS) as initiators were determined over the entire range of composition from pure AN to pure SSS, and it has been found that there is a sharp rise in copolymerization rates within 0.2–5 mole‐% monomer feed, sometimes being eight times larger than those in the neighboring range. The copolymerization in SSS monomer feed of 0.2–5 mole‐% occurs in the transition phase from homogeneous to heterogeneous, and the system is very viscous and slightly cloudy. From the investigation of the effect of initiator concentration on the copolymerization rate and the direct observation by an electron microscope, the sharp rise in copolymerization rates may reasonably be interpreted in terms of the emulsion copolymerization mechanism.
Thermodynamic properties of solutions of cellulose acetate and cellulose nitrate
Authors: Moore W. R. , Shuttleworth R. 
Published: April 2003

AbstractVapor pressure lowerings of solutions containing 10–50 wt.‐% of a secondary cellulose acetate and of a cellulose nitrate of similar degree of substitution in representative solvents have been measured over a range of temperature. Solvent activities and free energies, heats and entropies of dilution are obtained. At low polymer concentrations the cellulose acetate systems are endothermal but become exothermal at higher concentrations. Entropies of dilution show a somewhat similar variation with concentration when acetone, methyl acetate, and dioxane are used as solvents for the cellulose acetate, but with pyridine as solvent entropies are positive and increase with increasing polymer concentration. The systems cellulose nitrate‐acetone and cellulose nitrate‐methyl acetate are exothermal at all concentrations, but entropies of dilution are positive and increase with concentration from values not far from ideal to relatively large ones. An attempt is made to interpret these results in terms of solvation and chain stiffness. Values of the polymer‐solvent interaction parameter χ1 are obtained by use of polymer volume fractions calculated from the densities of the dry polymers. As the volume fraction of polymer increases in the cellulose acetate systems, χ1 would appear initially to fall from values characteristic of dilute solutions and then to increase. In the cellulose nitrate systems, χ1 falls from small positive to relatively large negative values. Values of the heat χh and entropy χs contributions to χ1 are also obtained. It is pointed out that it may be more logical to express polymer volume fraction in terms of solvated polymer and that this might lead to values of χ1, χh, and χs more in keeping with theories of polymersolvent interaction.