bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of poly(vinyl acetate) and poly(vinyl chloride‐ co‐vinyl acetate) low‐profile additives on properties of cured unsaturated polyester resins. I. Volume shrinkage characteristics and internal pigmentability
Authors: Huang Yan‐Jyi , Chen Tzong‐Shyang , Huang Jyh‐Gau , Lee Fuh‐Huah 
Published: July 2003

AbstractThree series of self‐synthesized poly(vinyl acetate)‐based low‐profile additives (LPAs) with different chemical structures and molecular weights, including poly(vinyl acetate), poly(vinyl chloride‐co‐vinyl acetate), and poly(vinyl chloride‐co‐vinyl acetate‐co‐maleic anhydride), were studied. Their effects on the volume shrinkage characteristics and internal pigmentability for low‐shrink unsaturated polyester (UP) resins during cure were investigated. The experimental results were examined with an integrated approach involving measurements of the static phase characteristics of the ternary styrene/UP/LPA system, the reaction kinetics, the cured sample morphology, and microvoid formation by using differential scanning calorimetry, scanning electron microscopy, optical microscopy, and image analysis. Based on the Takayanagi mechanical model, factors leading to both good volume shrinkage control and acceptable internal pigmentability for the molded parts were explored. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3336–3346, 2003
Graft polymerization of acrylonitrile onto starch‐coated polyethylene film surfaces
Authors: Fanta George F. , Felker Frederick C. , Salch John H. 
Published: July 2003

AbstractStarch‐coated polyethylene (PE) films were prepared by immersing PE in a hot, jet cooked solution of starch. They were allowed to react with acrylonitrile (AN) in the presence of ceric ammonium nitrate initiator, and the graft polymerization that occurred produced starch‐g‐polyacrylonitrile (PAN) coatings that contained about 25 wt % grafted PAN. The starch‐g‐PAN coatings tightly adhered to the PE film surfaces. When grafted starch coatings were wetted with water and the surfaces vigorously rubbed, less than 20% of the coating was removed. The fact that PAN‐grafted coatings were not removed with boiling water provided further evidence for their strong adherence. When starch was removed from the coating by acid hydrolysis, the residual grafted PAN still remained adsorbed on the PE surface. Because the grafted coating was completely removed by treatment with refluxing 0.7N sodium hydroxide, there is apparently no chemical bonding between starch‐g‐PAN and PE. The dimensional changes associated with the evaporation of water from these PAN‐grafted coatings caused the films to curl during drying. Because the final shape of these coated films depends upon the presence or absence of water in the surrounding environment, these films may be considered to be a type of stimulus‐responsive polymer. Attempts to graft polymerize methyl methacrylate and methyl acrylate onto starch‐coated PE surfaces, under conditions similar to those used with AN, were unsuccessful. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3323–3328, 2003
Influence of the molecular weight on the thermal and mechanical properties of ethylene/norbornene copolymers
Authors: Ekizoglou Nikos , Thorshaug Knut , Cerrada María L. , Benavente Rosario , Pérez Ernesto , Pereña José M. 
Published: July 2003

AbstractA series of ethylene‐norbornene copolymers were synthesized using Me2Si(Me4Cp)(NtBu)TiCl2 as the metallocene catalyst and methylaluminoxane (MAO) as the cocatalyst, with the same molecular characteristics except the molecular weight, to evaluate its influence on the determination of the glass transition temperature (Tg). The polymers were characterized using wide‐angle X‐ray scattering, differential scanning calorimetry, microhardness measurements, and dynamic mechanical thermal analysis. The value of the Tg, for the same norbornene content and determined from the last three mentioned methods, increases significantly up to a limit of Mn about 6–10 × 104 (g/mol). Above this value, Tg remains practically constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3358–3363, 2003
Copolymerization of carbon dioxide and ethyl vinyl ether at subcritical and supercritical conditions
Authors: Yokoyama Chiaki , Kawase Yasuo , Shibasaki‐Kitakawa Naomi , Smith Richard L. 
Published: July 2003

AbstractThe copolymerization of carbon dioxide (CO2) and ethyl vinyl ether (EVE) at subcritical and supercritical conditions was studied in the presence and absence of an aluminum triacetylacetonate [Al(acac)3] catalyst. The experiments took place at 313–423 K and 4–15 MPa and for reaction times of 12–120 h. We confirmed that CO2 could copolymerize with EVE with or without the Al(acac)3 catalyst, regardless of whether the vessel wall material was Teflon or stainless steel. With the Al(acac)3 catalyst, a maximum yield of 3.2% polymer was obtained at 338 K, 6 MPa, and 45 h. The maximum value of the average CO2 fraction was about 50% (100% of the theoretical) at 338 K, 15 MPa, and 45 h. Results confirmed the mechanism and pathways proposed earlier by Soga et al. (1973). There was a trade‐off between yield and the CO2 fraction incorporated into the polymer as conditions changed from subcritical to supercritical. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3167–3174, 2003
PNA‐positive glycoconjugates are negatively correlated with the access of neural crest cells to the gut in chicken embryos
Authors: Franchi De Freitas Patrícia , De Fátima Ferreira Fabiana , Ditzel Faraco Cloris 
Published: July 2003

AbstractNeural crest cells give rise to many derivatives, including the neurons and glia of the peripheral nervous system, adrenomedulary cells, and melanocytes, and migrate through precise pathways that differ according to their axial level and/or state of specification. The migratory routes taken by neural crest cells are reported to be regulated by extracellular matrix molecules. We examined the possible influence of glycoconjugates on the establishment of barriers to neural crest access to ventral regions leading to the gut, by labeling stage‐16–28 white Leghorn (WL) and Silky (SK) embryos with peanut agglutinin (PNA) at vagal, thoracic, and sacral levels. We observed a transitory expression of glycoconjugates that correlate with a barrier to the entrance of neural crest cells into the gut at the thoracic level, which is not present at vagal and sacral levels. In later stages, neural crest cells of melanocytic lineage were observed entering the gut in embryos of the SK chicken, a mutant with an altered pattern of pigmentation. The ventral regions occupied by melanoblasts in SK embryos were free of PNA labeling, while in WL embryos, in which PNA‐positive molecules are strongly expressed, melanoblasts were restricted to peripheral regions. We suggest that PNA‐binding glycoconjugates are good molecular marker for barriers that control the access of neural crest cells to the gut. Anat Rec Part A 273A:705–713, 2003. © 2003 Wiley‐Liss, Inc.
Lens structure in MIP‐deficient mice
Authors: Al‐Ghoul Kristin J. , Kirk Tyler , Kuszak Adam J. , Zoltoski Rebecca K. , Shiels Alan , Kuszak Jer R. 
Published: July 2003

AbstractIn this study we used correlative light, scanning, and transmission (freeze‐etch) electron microscopy to characterize lens structure in normal mice and compare it with that in mice deficient in the major intrinsic protein (MIP) of fiber cells. Grossly, wild‐type lenses were transparent and had typical Y sutures at all of the ages examined. These lenses had fibers of uniform shape (hexagonal in cross section) arranged in ordered concentric growth shells and radial cell columns. In addition, these fibers had normal opposite end curvature and lateral interdigitations regularly arrayed along their length. Ultrastructural evaluation of these fibers revealed anterior and posterior end segments characterized by square array membrane on low‐amplitude wavy fiber membrane. Approximately 13% of the equatorial or mid segments of these same fibers were specialized as gap junctions (GJs). In contrast, heterozygote lenses, while initially transparent at birth, were translucent by 3 weeks of age, except for a peripheral transparent region that contained fibers in the early stages of elongation. This degradation in clarity was correlated with abnormal fiber structure. Specifically, although the mid segment of these fibers was essentially normal, their end segments lacked normal opposite end curvature, were larger than normal, and had a distinct non‐hexagonal shape. As a result, these fibers failed to form typical Y sutures. Furthermore, the nuclear fibers of heterozygote lenses were even larger and lacked any semblance of an ordered packing arrangement. Grossly, homozygote lenses were opaque at all ages examined, except for a peripheral transparent region that contained fibers in the early stages of elongation. All fibers from homozygote lenses lacked opposite end curvature, and thus failed to form any sutures. Also, these fibers were essentially devoid of interlocking devices, and only 7% of their mid segment was specialized as GJs. The results of this study suggest that MIP has essential roles in the establishment and maintenance of uniform fiber structure, and the organization of fibers, and as such is essential for lens function. Anat Rec Part A 273A:714–730, 2003. © 2003 Wiley‐Liss, Inc.
Dynamic expression of Krüppel‐like factor 4 (Klf4), a target of transcription factor AP‐2α during murine mid‐embryogenesis
Authors: Ehlermann Julia , Pfisterer Petra , Schorle Hubert 
Published: July 2003

AbstractKrüppel‐like factor 4 (Klf4) belongs to the family of transcription factors that are thought to be involved in the regulation of epithelial and germ cell differentiation, based on their expression in postproliferative cells of the skin, gut, and testes. Gene ablation experiments suggest that Klf4 plays a role in keratinocyte differentiation, since mice lacking Klf4 fail to establish proper barrier function and, as a consequence, die postnatally due to dehydration. Recent studies have shown that Klf4 is also expressed in postnatal male mice, in postmeiotic sperm cells undergoing terminal differentiation into sperm cells. However, prior to the current study, the expression pattern of Klf4 during early and mid‐embryogenesis had not been examined. Here we demonstrate that Klf4 transcripts can be detected from embryonic day 4.5 (E4.5) on in the developing conceptus, and that Klf4 expression before E10 is restricted to extraembryonic tissues. The embryo proper displays a highly dynamic and changing Klf4 signal from E10 of murine development on. In addition to being expressed in a stripe of mesenchymal cells extending from the forelimb bud rostrally over the branchial arches to the developing eye, Klf4 is also expressed in the mesenchyme surrounding the nasal pit at day E11.5. In addition, Klf4 has been detected in the apical ectodermal ridge and adjacent mesenchymal cells in the limb buds, and in mesenchymal cells of the developing body wall in trunk areas. These findings suggest that Klf4 plays an important role in regulating cellular proliferation, which underlies the morphogenetic changes that shape the developing embryo. Anat Rec Part A 273A:677–680, 2003. © 2003 Wiley‐Liss, Inc.
Smad 3 regulates proliferation of the mouse ovarian surface epithelium
Authors: Symonds Daniel , Tomic Dragana , Borgeest Christina , McGee Elizabeth , Flaws Jodi A. 
Published: July 2003

AbstractSmad 3 is a signaling intermediate for the transforming growth factor beta (TGFβ) family; however, little is known about the role this protein plays in the regulation of the ovarian surface epithelium (OSE). Using a transgenic mouse model, we found that in the absence of Smad 3 there was a distinct morphological alteration of OSE cells. Wild‐type (WT) OSE was flat with thin cells, while Smad 3‐deficient (Smad 3 −/−) OSE was thick with plump cuboidal cells. WT OSE had less immunostaining for proliferating cell nuclear antigen (PCNA) and estrogen receptor alpha (ERα) than Smad 3 −/− OSE. However, there were no differences in the number of apoptotic cells or Bax and Bcl‐2 levels between WT and Smad 3 −/− OSE. Although WT mice had higher levels of serum estradiol than Smad 3 −/− mice, WT and Smad 3 −/− mice had similar levels of progesterone. These data suggest that Smad 3 regulates OSE morphological appearance and proliferation in the absence of high serum estradiol levels or alterations in progesterone levels. Anat Rec Part A 273A:681–686, 2003. © 2003 Wiley‐Liss, Inc.
The HGF/SF antagonist NK4 reverses fibroblast‐ and HGF‐induced prostate tumor growth and angiogenesis in vivo
Authors: Davies Gaynor , Mason Malcolm D. , Martin Tracey A. , Parr Christian , Watkins Gareth , Lane Jane , Matsumoto Kunio , Nakamura Toshikazu , Jiang Wen G. 
Published: July 2003

AbstractOur study examined the in vitro and in vivo responses of a newly discovered HGF/SF antagonist, NK4, on HGF/SF‐promoted growth of human prostate cancer cells (PC‐3). Nude mice were s.c. injected with either PC‐3‐ and/or HGF/SF‐producing fibroblasts (MRC5), and tumor size was measured over a 4‐week period. rh‐HGF/SF and/or NK4 were introduced by osmotic minipumps. An in vitro study found that NK4 significantly suppressed HGF/SF‐induced invasion (HGF/SF; p < 0.01 vs. HGF/SF+NK4) and migration (HGF/SF; p < 0.05 vs. HGF/SF+NK4). Similarly, NK4 also suppressed the invasion (MRC5; p < 0.01 vs. MRC5+NK4) and migration (MRC5; p < 0.05 vs. MRC5+NK4) induced by MRC5 cells. NK4 also suppressed HGF/SF‐ and MRC5‐induced tyrosine phosphorylation of the HGF/SF receptor Met as assessed by immunoprecipitation. Using a nude mouse model, prostate tumor volume (mm3) was significantly increased in both HGF/SF‐ (HGF/SF; p < 0.05 vs. control) and MRC5‐ (MRC5; p < 0.01 vs. control) treated groups compared to the control. In contrast, NK4 alone significantly reduced the growth of prostate tumors (NK4; p < 0.01 vs. control). In addition, NK4 also suppressed both HGF/SF‐ (HGF/SF; p < 0.01 vs. HGF/SF+NK4) and MRC5‐ (MRC5; p < 0.05 vs. MRC5+NK4) induced tumor growth in vivo by significantly reducing (p < 0.05) the degree of tumor angiogenesis using a recently discovered family of tumor endothelial markers (TEMs) by Q‐RT‐PCR analysis. In conclusion, NK4 suppresses both HGF/SF‐ and MRC5‐induced invasion/migration of PC‐3 cells in vitro. Furthermore, the HGF/SF antagonist NK4 significantly reduces prostate tumor growth in vivo by inhibiting the degree of tumor angiogenesis as determined by TEM‐1 and TEM‐8. Finally, our study provides evidence of the therapeutic potential of NK4 in prostate cancer development by antagonising HGF/SF‐mediated events. © 2003 Wiley‐Liss, Inc.
Persistence and load of high‐risk HPV are predictors for development of high‐grade cervical lesions: A longitudinal French cohort study
Authors: Dalstein Véronique , Riethmuller Didier , Prétet Jean‐Luc , Le Bail Carval Karine , Sautière Jean‐Loup , Carbillet Jean‐Pierre , Kantelip Bernadette , Schaal Jean‐Patrick , Mougin Christiane 
Published: July 2003

AbstractOncogenic HPV types are the major cause of worldwide cervical cancer, but only a small proportion of infected women will develop high‐grade cervical intraepithelial neoplasia or cancer (CIN2/3+). We performed a prospective study including 781 women with normal, atypical squamous cells of undetermined significance (ASCUS) or low‐grade squamous intraepithelial lesion (LGSIL) cytology, and infected or not by high‐risk (HR) HPV tested by Hybrid Capture II. Women were followed up every 6 months for a median period of 22 months. Among the HR‐HPV‐positive women at entry, more than half cleared their virus in 7.5 months; the clearance rate was greater for low viral loads than for high loads and also was higher in women with an initial ASCUS/LGSIL smear than in women with normal cytology. The incidence of cytologic abnormalities strongly depended on baseline viral load and HR‐HPV persistence. Maintenance of cytologic abnormalities was associated with the outcome of HR‐HPV status (negative<transient<persistent) but not with baseline load. Progression to CIN2/3+ was achieved only in women with persistent HR‐HPV infection. The risk of CIN2/3+ also was increased with initial high loads (≥100 pg/mL). Conversely, women who were consistently HR‐HPV negative or transiently HR‐HPV positive, whatever the cytology at baseline was, did not develop CIN2/3+ during follow‐up. Age seemed to affect only the rate of incident HR‐HPV infection. In conclusion, our data suggest that women repeatedly tested positive for HR‐HPV are at risk of developing CIN2/3+, even when initial cytology is normal. A high viral load could be used as a short‐term marker of progression toward precancerous lesions, although lower load does not inevitably exclude progressive disease. © 2003 Wiley‐Liss, Inc.
RETRACTED: Enhanced susceptibility of oral squamous cell carcinoma cell lines to FAS‐mediated apoptosis by cisplatin and 5‐fluorouracil
Authors: Iwase Masayasu , Watanabe Hitoshi , Kondo Gen , Ohashi Masaru , Nagumo Masao 
Published: July 2003

AbstractOur study was conducted to investigate whether anticancer drugs, cisplatin (CDDP) and/or 5‐fluorouracil (5‐FU), can modulate Fas‐mediated apoptosis in oral squamous cell carcinoma (OSCC) cell lines. When OSCC cell lines, NA and HSC‐4, were treated with CDDP and/or 5‐FU, Fas and its mRNA expression on the plasma membrane were enhanced. An increase in caspase‐3 and ‐8 activities was then observed by the addition of agonistic anti‐Fas antibody, CH‐11. Apoptosis of OSCC cells treated with anticancer drugs were significantly enhanced by CH‐11, whereas untreated cells were nearly resistant to apoptosis. Moreover, the combination of CDDP and 5‐FU resulted in an increasing susceptibility to apoptosis. Caspase‐3 and ‐8 inhibitors, but not caspase‐9 inhibitor, reduced Fas‐mediated apoptosis enhanced by the anticancer drugs. Furthermore, OSCC cells treated with anticancer drugs exhibited decreased cellular FADD‐like interleukin 1‐converting enzyme‐inhibitory protein (c‐FLIP) levels, whereas neither the Fas‐associated death domain‐containing protein (FADD) nor procaspase‐8 changed the expression. Moreover, antisense oligonucleotide to c‐FLIP confirmed that down‐regulation of c‐FLIP induced sensitization to Fas‐mediated apoptosis. These results suggest that CDDP and 5‐FU may enhance the susceptibility to Fas‐mediated apoptosis through down‐regulation of c‐FLIP. From these findings, a new potential strategy may be developed to improve the efficacy of anticancer drugs. © 2003 Wiley‐Liss, Inc.
Antihistamine use and breast cancer risk
Authors: Nadalin Victoria , Cotterchio Michelle , Kreiger Nancy 
Published: July 2003

AbstractAntihistamines are structurally similar to DPPE, a tamoxifen derivative known to promote tumor growth, and to antidepressants. Animal experiments have linked certain antihistamines and antidepressants with enhanced tumor growth in mice. The few epidemiologic studies examining antihistamine use have not indicated an increased risk. In light of suggestive animal data, structural similarities between antihistamines and DPPE, the widespread use of antihistamines, and the lack of epidemiologic investigation into their use and breast cancer risk, it is important to examine this issue. Female cases aged 25–74 years, diagnosed 1996 to 1998, were identified through the Ontario Cancer Registry. Controls were a random, age‐matched sample of women. Cases (n=3,133) and controls (n=3,062) completed a mailed questionnaire that included questions about antihistamines used regularly (undefined), type and duration. Age‐adjusted odds ratio (OR) estimates and 95% confidence intervals (CIs) were obtained using logistic regression. Antihistamine users were at no increased risk for breast cancer (OR=0.93, 95% CI: 0.81, 1.06), and no trend in risk was observed for age starting or duration of use. Antihistamine users were at no increased risk. No confounding or effect modification was identified in multivariate modeling. Our findings do not support the hypothesis that women who use antihistamines are at a greater breast cancer risk than those who do not. © 2003 Wiley‐Liss, Inc.
Histogenesis of hepatoid adenocarcinoma of the stomach:Molecular evidence of identical origin with coexistent tubular adenocarcinoma
Authors: Akiyama Sunao , Tamura Gen , Endoh Yasushi , Fukushima Norimasa , Ichihara Yukihiro , Aizawa Kikuo , Kawata Sumio , Motoyama Teiichi 
Published: July 2003

AbstractHepatoid adenocarcinoma of the stomach is a highly malignant neoplasm. Most gastric hepatoid adenocarcinomas coexist with tubular adenocarcinoma. However, the relationship between hepatoid adenocarcinoma and tubular adenocarcinoma is still unclear. In the present study, the characteristics of the coexistent tubular adenocarcinomas were determined by examining their profiles of mucin production. Subsequently, molecular pathological techniques were applied to determine the clonality of 15 mixed hepatoid and tubular adenocarcinomas of the stomach. Mucin analysis suggested that the coexistent tubular adenocarcinomas with hepatoid adenocarcinoma were of the intestinal type. The patterns of chromosome X inactivation were identical between the hepatoid adenocarcinoma component and tubular adenocarcinoma component in all of 3 informative female cases. Mutations in the p53 gene were found in 5 cases. The sequences were identical within both tumor components in all 5 cases. Microsatellite analysis indicated more than 3 common patterns of loss of heterozygosity in 8 cases. These observations strongly suggested that hepatoid adenocarcinomas were of identical origin to coexistent tubular adenocarcinomas. © 2003 Wiley‐Liss, Inc.
In vitro and in vivo biologic evaluation of long‐circulating biodegradable drug carriers loaded with the pure antiestrogen RU 58668
Authors: Ameller Thibault , Marsaud Véronique , Legrand Philippe , Gref Ruxandra , Renoir Jack‐Michel 
Published: July 2003

AbstractWe have developed a parenteral delivery system for the administration of the highly promising pure antiestrogen RU 58668 (RU). Two types of nanoparticles (NP) made of biodegradable copolymers and coated with polyethylene‐glycol (PEG) chains were prepared: nanospheres (NS) (diameter, ∼110 nm) and nanocapsules (NC) with an oily core (diameter, ∼250 nm). The amount of RU incorporated into NS and NC was ∼33 vs. ∼5 μg RU/mg of polymer, respectively. Coating with PEG chains prolonged the antiestrogenic potency of RU, as shown by a prolonged antiuterotrophic activity of encapsulated RU into PEG‐poly(D,L lactic acid) (PLA) NS, as compared to that of conventional nonpegylated NS. In mice bearing MCF‐7 estrogen‐dependent tumors, free RU injected at 4.3 mg/kg/week by i.v. route slightly decreased the estradiol‐promoted (0.5 mg/kg/week) tumor growth while RU‐loaded PEG‐PLA NS injected at the same dose strongly reduced it. Analysis of cell cycle parameters in tumors treated with RU indicated that RU‐loaded PEG‐PLA NS injected at 4.3 mg/kg/week in MCF‐7 tumors decreased cyclin D1 and cyclin E simultaneously, and increased p27. The antitumoral activity of RU encapsulated within pegylated NC was stronger than that of RU entrapped with pegylated NS loaded at an equivalent dose. Indeed, the former decreased the tumor size in nude mice transplanted with the estrogen receptor‐positive but estrogen‐independent MCF‐7/Ras breast cancer cells at a concentration 2.5 times lower than that of the latter (0.4 mg/kg/week compared to 1 mg/kg/week). Empty PEG‐PLA NS and NC were devoid of antiuterotrophic and antitumoral activities. Altogether, these results suggest that the incorporation of the pure antiestrogen RU into long‐circulating NP could represent a novel antiestrogen drug delivery system for the parenteral route. © 2003 Wiley‐Liss, Inc.