bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transcript profiling of enzymes involved in detoxification of xenobiotics and reactive oxygen in human normal and simian virus 40 T antigen‐immortalized oral keratinocytes
Authors: Vondracek Martin , Weaver David A. , Sarang Zsolt , Hedberg Jesper J. , Willey James C. , Wärngård Lars , Grafström Roland C. 
Published: August 2002

AbstractThe metabolic detoxification capacity may critically regulate the susceptibility of human tissues to cancer development. We used standardized and quantitative, reverse transcription‐polymerase chain reaction (StaRT‐PCR) and microarray chip techniques to analyze transcript levels of multiple detoxification enzymes in cultured normal human oral keratinocytes (NOK) and the Siman virus 40 T antigen‐immortalized oral keratinocyte line SVpgC2a, viewing the latter as a model of a benign tumor state. With good agreement between the 2 methodologies, NOK and SVpgC2a were found to express transcripts for cytochrome P450 enzymes (CYPs), factors related to CYP induction and enzymes involved in conjugation reactions or detoxification of reactive oxygen. The cell types expressed similar levels of CYP 2B6/7, CYP 2E1, P450 oxidoreductase, the aryl hydrocarbon receptor nuclear translocator, sulfotransferase 1A1, sulfotransferase 1A3, epoxide hydrolase, glutathione S‐transferase M3, glutathione S‐transferase pi and catalase, superoxide dismutase 1, glutathione peroxidase 1 and glutathione peroxidase 3. In contrast, SVpgC2a exhibited comparatively higher levels of CYP1A1, 1B1, aryl hydrocarbon receptor, glutathione S‐transferase M1, 2, 4, 5, glutathione S‐transferase theta 1 and superoxide dismutase 2 and comparatively lower levels of UDP glycosyltransferase 2 and microsomal glutathione S‐transferase 1. Some transcripts, e.g., CYP 2A6/7, were not detected by either standard, non quantitative RT‐PCR or the above methods, whereas others were barely quantifiable by StaRT‐PCR, i.e., were present at 1–10 molecules/106 molecules of actin. Overall, the expression analysis demonstrated presence of mRNA for multiple enzymes involved in foreign compound metabolism and detoxification pathways, including several enzymes not previously reported for oral epithelium. Generally, the comparison of NOK from 2 individuals indicated relatively similar transcript levels of these enzymes. In contrast, differences between NOK and SVpgC2a, e.g., for CYP1B1, may reflect alteration caused by immortalization and aid identification of early stage tumor markers in oral epithelium. © 2002 Wiley‐Liss, Inc.
MSI in endometrial carcinoma: Absence of MLH1 promoter methylation is associated with increased familial risk for cancers
Authors: Whelan Alison J. , Babb Sheri , Mutch David G. , Rader Janet , Herzog Thomas J. , Todd Christina , Ivanovich Jennifer L. , Goodfellow Paul J. 
Published: August 2002

AbstractLoss of DNA mismatch repair occurs in a variety of malignancies and is associated with genome‐wide instability of microsatellite repeats, a molecular phenotype referred to as microsatellite instability (MSI). MSI is a consistent feature of colorectal and endometrial tumors from patients with hereditary non‐polyposis colorectal cancer (HNPCC). Sporadic colorectal and endometrial cancers that exhibit MSI frequently have methylation of the MLH1 promoter. We undertook a detailed family and medical history study to compare family cancer risk for women with MSI‐positive and ‐negative endometrial cancers. The MLH1 promoter methylation status was determined for all cancers. Family histories were developed for 80 probands (40 with MSI‐positive and 40 with MSI‐negative tumors). The numbers of reported cancers in first‐ and second‐degree relatives of the 2 groups were similar. There was a modest increase in familial cancer clustering for MSI‐positive probands. When MSI‐positive tumors were subclassified according to MLH1 promoter methylation, a clear association between methylation status and familial cancer risk was evident. Women with MSI‐positive endometrial cancers in which the MLH1 promoter was unmethylated had a 7‐fold relative risk (RR) of demonstrating familial clustering of cancers [RR 7.07 (95% confidence interval 2.29–21.81)]. The women with MSI‐positive, MLH1‐unmethylated tumors were significantly younger than the rest of the study population (56.1 years vs. 65.4, p ≤ 0.01). Age of onset and tumor MSI not associated with MLH1 promoter methylation may point to women with a genetic susceptibility to malignancies. © 2002 Wiley‐Liss, Inc.
Identification and characterization of 9D7, a novel human protein overexpressed in renal cell carcinoma
Authors: Klade Christoph S. , Dohnal Alexander , Fürst Walter , Sommergruber Wolfgang , Heider Karl‐Heinz , Gharwan Helen , Ratschek Manfred , Adolf Günther R. 
Published: August 2002

AbstractWith the objective of discovering novel tumor‐associated antigens of the cancer/testis type, we compared the transcriptional profiles of renal cell carcinoma (RCC) and non‐tumorous kidney and further screened for genes expressed in RCC and testis, but not other normal tissues. In a first step, a representational difference analysis library consisting of approximately 1,900 RCC cDNA clones was generated. Clones were then spotted onto filters and hybridized with cDNA probes derived from a testis‐specific cDNA library, a pool of RCCs and a pool of 10 healthy normal tissues, respectively. Based on strong hybridization signals with both RCC and testis, but not normal tissue probes, 185 clones were sequenced and annotated. After EST‐database comparison, 35 clones were selected for experimental analysis, including conventional and quantitative RT‐PCR as well as Northern blotting. Clone 9D7 showed strong mRNA expression in RCC as well as in several other major tumor types. In normal tissues there was little or no mRNA expression with the exception of heart. 9D7 was cloned to full‐size and found to represent a novel human gene containing 5 exons residing on chromosome 14. Alternative splicing within exon 1 generates 2 open‐reading‐frames consisting of 717 or 435 bp corresponding to predicted proteins of 239 or 145 amino acids. 9D7 shows high homology (227/239 amino acids or 95% identity) to a growth factor‐inducible gene of Rattus norvegicus involved in apoptosis. In situ hybridization as well as immunohistochemical analysis using 9D7‐specific antisera confirmed overexpression of 9D7 in RCCs as compared to normal kidney tissue. © 2002 Wiley‐Liss, Inc.
Resistance to tamoxifen‐induced apoptosis is associated with direct interaction between Her2/neu and cell membrane estrogen receptor in breast cancer
Authors: Chung Yih‐Lin , Sheu Meei‐Ling , Yang Shun‐Chun , Lin Chi‐Hung , Yen Sang‐Hue 
Published: August 2002

AbstractOverexpression of Her2/neu is implicated in the development of resistance to the antiestrogen tamoxifen (TAM) that exerts its inhibitory effect through interaction with estrogen receptor (ER). Whereas Her2/neu and ER are believed to be important cell survival/death factors in human breast cancer cells, if and how they interact to confer resistance to hormone therapy is not known. This prompted us to investigate whether modulation of the effect of TAM occurs via the Her2/neu pathway and whether targeting the interaction between the Her2/neu pathway and the ER pathway is beneficial. There are 2 forms of ER that are localized to the cell membrane and to the nucleus. For the first time, we found that Her2/neu directly interacts with ER at the cell membrane. We then investigated the role of Her2/neu overexpression in the regulation of the cell membrane ER pathway in TAM‐resistant breast cancer cells and the nature of this interaction in apoptotic signaling. Relief of TAM resistance was associated with Her2/neu downregulation and ER upregulation. TAM‐induced apoptosis occurred immediately after dissociation of Her2/neu from cell membrane ER. These results demonstrate a novel mechanism by which Her2/neu regulates the cell membrane ER‐coupled apoptosis and the possible involvement of the Her2/neu in TAM resistance of breast cancer cells. Moreover, the antiproliferative activity of TAM should rely on the integration between the signal transduction from the cell membrane ER and the gene regulation by the nuclear ER. Coordinated modulation on the cell membrane ER/Her2/neu pathway and the nuclear ER/RAR pathway may provide a new approach for treatment of ER‐positive, Her2/neu overexpressing breast cancer. © 2001 Wiley‐Liss, Inc.
Assessing the risk of nasopharyngeal carcinoma on the basis of EBV antibody spectrum
Authors: Cheng Wei‐min , Chan Kwok Hung , Chen Hong‐lin , Luo Rui‐xian , Ng S. Park , Luk Winsie , Zheng Bo‐jian , Ji Ming‐fang , Liang Jin‐sheng , Sham Jonathan S.T. , Wang De‐Kun , Zong Yong‐sheng , Ng Mun Hon 
Published: August 2002

AbstractWe have evaluated the performance of 3 new EBV ELISA for the diagnosis of nasopharyngeal carcinoma (NPC). The tests were specific for EBNA 1 IgA, EBNA 1 IgG and zta IgG, respectively. Their distinct antigenic specificity permits these assays to be used in concert in an approach that differentiates patients and apparently healthy subjects on the basis of their antibody spectrum. By so exploiting a distinguishing feature of NPC first described by the late Werner Henle that the patients sustain high levels of a broad spectrum of serum EBV antibodies, this approach achieved a sensitivity of 92% and a specificity of 93%, surpassing the performance of each of these assays individually. The enhanced performance is especially useful in population screening. It was shown that relative risk of NPC sustained by apparently healthy subjects residing in a high incidence area for NPC in the Pearl River estuary in Southern China may vary according to EBV antibody spectrum. The risk of the cancer was markedly reduced with odds ratios of 0.009 for 59% of those who had low level of all 3 antibodies. The risk was increased as antibody spectrum broadens and the risk was the highest with an odds ratio of 138 for 0.4% of those who had high levels of all 3 antibodies. Thus, EBV antibody spectrum may serve to guide follow‐up measures for early detection of the cancer and/or risk counseling according to level of the risk of the cancer sustained by the screened individuals. © 2001 Wiley‐Liss, Inc.
Getting dads involved: Predictors of father involvement in Early Head Start and with their children
Authors: Roggman Lori A. , Boyce Lisa K. , Cook Gina A. , Cook Jerry 
Published: August 2002

AbstractFather characteristics and psychosocial functioning were examined as predictors of father involvement both with an Early Head Start (EHS) program and with their infant. Variables examined as potential predictors were selected based on the program's emphasis on building relationships as their primary intervention strategy. The 72 low‐income fathers included in this study were predominantly Caucasian and married or living with their child's mother. Fathers' characteristics predicted their involvement in expected ways. Fathers were rated as more involved, both with their infants and with the EHS program, when they were better educated, less depressed, more likely to use social support especially spiritual support, and more active in their religion. Fathers who had better relationships with home visitors were those who had these same characteristics and also were less anxious about close relationships. In addition, fathers who were later rated as more engaged with their infants reported doing more activities with their infants at 10 months. These results suggest that the fathers who most need support to become more involved with their children are likely to be those who are the most difficult to get involved in an EHS program. ©2002 Michigan Association for Infant Mental Health.
Full cost or “sustainability cost” pricing in irrigated agriculture. Charging for water can be effective, but is it sufficient?
Authors: Tardieu Henri , Préfol Bernard 
Published: August 2002

AbstractIn France, the water management issue is no longer a matter of developing stakeholder participation or transferring state competence to user associations. But, as for other countries with a significant irrigated agriculture, two socio‐economic questions need to be answered: (i) How to ensure the sustainability of investments by raising the price of water without discouraging economic development? (ii) How to share water between users when resources are scarce?Answering these questions brings up the two basic principles of good water management for sustainable development: as it consumes more than 70% of the available water of low flow periods, irrigated agriculture must respect the other uses by limiting its demand to the allocated volume; as it involves large and long‐term public investments, irrigated agriculture must at least bear the “sustainability cost” of the irrigation schemes including the upstream water resources. Such a general answer is of course largely case‐specific and should be adjusted to each institutional framework. In France today, the Sociétés d'Aménagement Régional (SARs) are currently applying these principles. This paper will address both socio‐economic questions stated above, with a specific discussion on the case of a water‐stressed basin in the south west of France where a specific step‐pricing and quota system has been set up in order to regulate the demand. It is argued that “full cost pricing of water services”, as recommended in the World Water Vision (The Hague 2000), is not practical in the short term and, if pursued, could lead to very undesirable results. As a conclusion, two recommendations are proposed with a view to developing best practices in charging for water. Copyright © 2002 John Wiley & Sons, Ltd.
Potential protective role of angiotensin‐converting enzyme inhibitors captopril and enalapril against adriamycin‐induced acute cardiac and hepatic toxicity in rats
Authors: Abd El‐Aziz M. A. , Othman A. I. , Amer M. , El‐Missiry M. A. 
Published: August 2002

AbstractCaptopril and enalapril—angiotensin‐converting enzyme (ACE) inhibitors—were evaluated for their antioxidative protective action against adriamycin‐induced cardiac and hepatic toxicity. Rats were treated with either captopril (10 mg kg−1) or enalapril (2 mg kg−1) intragastrically (i.g.) daily for 7 days before single intraperitoneal (i.p.) injection with adriamycin (15 mg kg−1). The animals were killed 30 h after adriamycin administration. Adriamycin produced significant elevation in thiobarbituric acid reactive substances (TBARS), which is an indicator of lipid peroxidation, and significantly inhibited the activity of superoxide dismutase (SOD) in heart and liver tissues, with a significant rise in the serum levels of glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), creatine kinase isoenzyme (CK‐MB) and lactic dehydrogenase (LDH), indicating acute cardiac toxicity. A single injection of adriamycin did not affect the cardiac or hepatic glutathione (GSH) content or cardiac catalase (CAT) activity, but hepatic CAT activity was elevated. Pretreatment with ACE inhibitors significantly reduced the TBARS concentration in both heart and liver and ameliorated the inhibition of cardiac and hepatic SOD activity. In addition, the ACE inhibitors significantly improved the serum levels of GOT, GPT, CK‐MB and LDH in adriamycin‐treated rats. Thus, these results suggest that captopril and enalapril possess antioxidative potential that may protect the heart against adriamycin‐induced acute oxidative toxicity. This protective effect might be mediated, at least in part, by the limitation of culprit free radicals and the amelioration of oxidative stress. Copyright © 2001 John Wiley & Sons, Ltd.
Cationic lipid‐mediated transfection of bovine aortic endothelial cells inhibits their attachment
Authors: Kader Khalid N. , Sweany Jon M. , Bellamkonda Ravi V. 
Published: August 2002

AbstractThe need for a small‐diameter vascular graft for coronary artery and peripheral vascular replacement is great and is projected to increase as the population ages. Synthetic small‐diameter vascular grafts fail because of acute thrombosis or chronic intimal hyperplasia leading to restenosis. Endothelial cell seeding has been attempted with limited success in the femoral artery by Zilla and others. However, patency rates have not increased sufficiently to justify large clinical trials. Genetic engineering of endothelial cells before seeding has been proposed to encourage endothelial cell phenotypes that would predispose the graft to patency. In this study, we investigate the effect cationic lipid‐mediated transfection of endothelial cells with respect to their attachment to a potential graft material, Fluoropassiv™ (Vascutek). Liposomal transfection was optimized for maximum gene expression. We report that transfection decreases the ability of bovine aortic endothelial cells to attach by approximately 100% as compared with nontransfected control over 18 h. Further, when placed under physiologic shear conditions, this difference is sustained. The effects of gene transfer on endothelial cell adhesion must be included as an important optimization criterion along with gene expression for engineered endothelial cell‐seeding applications. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 405–410, 2002; DOI 10.1002/jbm.10062
Analysis of acid‐treated dentin smear debris and smear layers using confocal Raman microspectroscopy
Authors: Wang Yong , Spencer Paulette 
Published: August 2002

AbstractSmear layers are generally present on any dentin surface prepared with cutting instruments and are often the only available substrate for bonding. It is commonly reported that acid removes these layers, but to date there has been no chemical evidence to support this observation. Confocal Raman microspectroscopy was used to investigate changes in the composition and molecular structure of acid‐treated smear debris and in situ dentin smear layers. The exposed dentin in human molars was abraded with 600‐grit silicon carbide sandpaper. Raman spectra were acquired on the smear debris and collected from the sandpaper before and after treatment with 10% citric acid, 35% H3PO4, or 0.5M ethylenediaminetetraacetic acid (EDTA). The resultant smeared dentin samples were treated with one of the aforementioned reagents, and spectra were acquired at 1.0‐μm intervals across the interfaces of the smear layers/demineralized dentin/mineralized dentin. Corresponding specimens were morphologically analyzed with scanning electron microscopy (SEM). The results showed that the composition of the smear debris and the in situ smear layers was a mixture of disorganized collagen and mineral. Spectral changes in the smear debris suggested that the disorganized collagen was denatured by acid treatment. The denatured collagen formed a gelatinous matrix around the mineral in the smear layer, thereby shielding it from the acid. The smear layers were not apparent in the SEM micrographs of acid‐etched dentin prepared and processed with conventional techniques. The micro‐Raman spectroscopic results presented in this study provide the first direct evidence that partially denatured collagen within smear layers is not removed and that the mineral is only partially removed with acids that represent conventional dentin adhesive etchants. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 300–308, 2002; DOI 10.1002/jbm.10108
Synthesis, characterization, and cytocompatibility of elastomeric, biodegradable poly(ester‐urethane)ureas based on poly(caprolactone) and putrescine
Authors: Guan Jianjun , Sacks Michael S. , Beckman Eric J. , Wagner William R. 
Published: August 2002

AbstractThe engineering of tissue for mechanically demanding applications in the cardiovascular system is likely to require mechanical conditioning of cell–scaffold constructs prior to their implantation. Scaffold properties amenable to such an application include high elasticity and strength coupled with controllable biodegradative and cell‐adhesive properties. To fulfill such design criteria, we have synthesized a family of poly(ester‐urethane)ureas (PEUUs) from polycaprolactone and 1,4‐diisocyanatobutane. Lysine ethyl ester (Lys) or putrescine was used as chain extenders. To encourage cell adhesion, PEUUs were surface modified with radio‐frequency glow discharge followed by coupling of Arg‐Gly‐Asp‐Ser (RGDS). The synthesized PEUUs were highly flexible, with breaking strains of 660–895% and tensile strengths from 9.2–29 MPa. Incubation in aqueous buffer for 8 weeks resulted in mass loss, from >50% (Lys chain extender) to 10% (putrescine chain extender). Human endothelial cells cultured for 4 days with medium containing the degradation products from PEUUs with either the Lys or putrescine chain extender showed no toxic effects. Cell adhesion was 85% of that measured on tissue‐culture polystyrene for unmodified PEUU surfaces (p < 0.01) and >160% (p < 0.001) of polystyrene on RGDS‐modified PEUUs. These biodegradable PEUUs demonstrate potential for future application as cell scaffolds in cardiovascular tissue‐engineering or other soft‐tissue applications. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 61: 493–503, 2002
Hydroxyapatite ceramic bodies with tailored mechanical properties for different applications
Authors: Rodríguez‐Lorenzo L. M. , Vallet‐Regí M. , Ferreira J. M. F. , Ginebra M. P. , Aparicio C. , Planell J. A. 
Published: August 2002

AbstractA perfect control on the final ceramic features will enable the research/clinical community to spread the use of calcium phosphate ceramic bodies to a large number of applications and/or requirements. The mechanical properties of hydroxyapatite ceramic bodies manufactured by different techniques and with different porosities is presented. The flexural strength, hardness, fracture toughness, surface roughness, and their evolution after immersion in SBF are studied. An increase of the mechanical properties with density is observed. The factors governing these results are analyzed. The increase of the porosity percentage of the bodies results in an increase on the surface roughness. The degradation studies show that the HA ceramics keep their integrity and mechanical properties under physiological conditions during the soaking time studied. The OHAp ceramic bodies with controlled porosity could be appropriated for hard tissue substitution or as a carriers for controlled delivery of drugs or as scaffolds for tissue engineering. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 159–166, 2002