bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seasonal inundation patterns in two large savanna floodplains of South America: the Llanos de Moxos (Bolivia) and the Llanos del Orinoco (Venezuela and Colombia)
Authors: Hamilton Stephen K. , Sippel Suzanne J. , Melack John M. 
Published: July 2004

AbstractInundation patterns in two of the largest savanna floodplains of South America were studied by analysis of the 37‐GHz polarization difference observed by the Scanning Multichannel Microwave Radiometer (Nimbus‐7 satellite). Flooded area was estimated at monthly intervals for January 1979 through to August 1987 using mixing models that account for the major landscape units with distinctive microwave emission characteristics. Results are presented separately for five subregions in each of the two floodplain regions to show the spatial as well as temporal variability in inundation patterns. The total area inundated during the 9 years varied between 2069 and 78 460 km2 in the Llanos de Moxos (also spelled as Mojos; median area, 23 383 km2) and 1278 and 105 454 km2 in the Llanos del Orinoco (median, 25 374 km2), not including the open‐water area of permanent lakes and river channels. The correlation between flooded area and river stage was used to extend the inundation records over a 30‐year period in the Moxos (1967–97) and a 58‐year period (1927–85) in the Orinoco. Interannual variability in inundation is greater in the Moxos than the Orinoco. Comparison of these data, however, with a previously published analysis of the Pantanal wetland shows that inundation patterns in these two floodplain regions are not as variable across years as they are in the Pantanal. Copyright © 2004 John Wiley & Sons, Ltd.
Vascular density in colorectal liver metastases increases after removal of the primary tumor in human cancer patients
Authors: Peeters Charlotte F.J.M. , Westphal Johan R. , de Waal Robert M.W. , Ruiter Dirk J. , Wobbes Theo , Ruers Theo J.M. 
Published: July 2004

AbstractIn animal models, explosive growth of metastases after removal of the primary tumor has been attributed to abolishment of angiogenesis inhibition. We investigated the influence of (removal of) the primary tumor on vascularization of liver metastases in human colorectal cancer patients. We analyzed vascular density in synchronous liver metastases from patients with the primary tumor in situ, in synchronous metastases from patients with the primary tumor resected and in metachronous metastases. In a limited number of cases, biopsies from metastases from the same patient before and within 3 months after resection were analyzed. In addition, vascular density in metastases was compared to the vascular density in the corresponding primary tumor. Peritumoral and intratumoral vascular density were determined by staining for endothelial antigens CD31 and CD34, respectively. Both peritumoral and intratumoral vascular density were elevated in synchronous metastases from patients with the primary tumor removed compared to synchronous metastases from patients with the primary tumor in situ. Comparable results were observed in patients with metachronous metastases. An increase in vascular density after resection of the colorectal malignancy was also observed in biopsies taken from the same patient before and after tumor resection. Remarkably, vascular density in the liver metastases was always lower than that in the corresponding primary tumor. Our data show for the first time in humans that the presence of a primary tumor is correlated with decreased vascularization of its distant metastases. Resection of the primary tumor results in an increased vascularization of metastatic lesions. © 2004 Wiley‐Liss, Inc.
Coamplification and coexpression of GRB7 and ERBB2 is found in high grade intraepithelial neoplasia and in invasive Barrett's carcinoma
Authors: Walch Axel , Specht Katja , Braselmann Herbert , Stein Hubert , Siewert Jörg Rüdiger , Hopt Ulrich , Höfler Heinz , Werner Martin 
Published: July 2004

AbstractThe human growth factor receptor‐bound protein 7 gene (GRB7), the founding member of a family of adaptor molecules has been shown to regulate cell migration and has been implicated in tumor progression. GRB7 is localized in close proximity to the ERBB2 gene within an amplicon previously identified in Barrett's adenocarcinoma (BCA). We evaluated gene amplification and mRNA expression of GRB7 and ERBB2 in Barrett's carcinoma and its associated precursor lesions to assess their possible role in Barrett's malignant transformation. Copy number and expression levels were analyzed by Q‐PCR (GRB7, ERBB2) and QRT‐PCR (GRB7, ERBB2) using TaqMan technology and fluorescence in situ hybridization (ERBB2) in a series of 24 laser‐microdissected samples of Barrett's carcinomas and 32 samples of associated premalignant lesions. Parallel analysis of gene copy number changes and expression levels demonstrated that GRB7 and ERBB2 displayed concomitant elevated expression levels and increased copy numbers in 32% of Barrett's carcinomas. There was a correlation between GRB7 and ERBB2 in BCA at the DNA level (rs = 0.76, p < 0.001) and the mRNA level (rs = 0.89, p < 0.001). Moreover, coamplification (rs = 0.97, p < 0.001) and coexpression (rs = 0.81, p < 0.001) of GRB7 and ERBB2 are shown to be already present in a subset of BCA associated high‐grade intraepithelial neoplasia (HGIN), possibly reflecting a role of a concerted expression of GRB7 and ERBB2. No alterations, neither gene amplification nor overexpression were detected in Barrett's carcinoma associated low grade intraepithelial neoplasia (LGIN), intestinal metaplasia (IM) and squamous epithelium, indicating that alterations of GRB7 and ERBB2 are late events in the carcinogenesis of Barrett's esophagus. These findings may be of particular interest because the transition from high grade intraepithelial neoplasia to invasive carcinoma is a crucial step in malignant transformation in Barrett's carcinogenesis and might underline the putative role of GRB7 and ERBB2 in cell migration and tumor invasion. © 2004 Wiley‐Liss, Inc.
Epigenetic inactivation of RUNX3 in microsatellite unstable sporadic colon cancers
Authors: Goel Ajay , Arnold Christian N. , Tassone Pierfrancesco , Chang Dong K. , Niedzwiecki Donna , Dowell Jeannette M. , Wasserman Linda , Compton Carolyn , Mayer Robert J. , Bertagnolli Monica M. , Boland C. Richard 
Published: July 2004

AbstractRunt domain transcription factors are important targets of TGF‐β superfamily proteins and play a crucial role in mammalian development. Three mammalian runt‐related genes, RUNX1, RUNX2 and RUNX3, have been described. RUNX3 has been shown to be a putative tumor suppressor gene localized to chromosome 1p36, a region showing frequent loss of heterozygosity events in colon, gastric, breast and ovarian cancers. Because of the important role of TGF‐β signaling in the human colon, we hypothesized that RUNX3 may serve as a key tumor suppressor in human colon cancers and colon cancer‐derived cell lines. We examined RUNX3 expression and the frequency of RUNX3 promoter hypermethylation in 17 colon cancer cell lines and 91 sporadic colorectal cancers. Semiquantitative analysis of RUNX3 transcripts was performed by RT‐PCR and de novo methylation of the RUNX3 promoter was studied by a methylation‐specific PCR (MSP) assay. Nineteen of 91 informative tumors (21%) and 11 of 17 (65%) colon cancer cell lines exhibited hypermethylation of the RUNX3 promoter. Interestingly, RUNX3 promoter hypermethylation was more common in tumors exhibiting high frequency of microsatellite instability (MSI‐H) (33% of MSI‐H vs. 12% of MSI‐L/MSS tumors; p = 0.012). Hypermethylation of the RUNX3 promoter correlated with loss of mRNA transcripts in all cell lines. RUNX3 promoter methylation was reversed and its expression restored in SW48 and HCT15 colon cancer cells after treatment with the demethylating agent 5‐aza‐2′‐deoxycytidine, indicating that loss of expression is caused by epigenetic inactivation in colon carcinogenesis. This is the first demonstration of frequent de novo hypermethylation of the RUNX3 promoter in sporadic colon cancers. The significant association of RUNX3 promoter hypermethylation with MSI‐H colon cancers suggests that RUNX3 is a novel target of methylation, along with the hMLH1 gene, in the evolution of MSI‐H colorectal cancers. © 2004 Wiley‐Liss, Inc.
In vitro and in vivo antitumor effect of 2‐methoxyestradiol on human melanoma
Authors: Dobos Judit , Tímár József , Bocsi József , Burián Zsuzsanna , Nagy Katalin , Barna Gábor , Peták István , Ladányi Andrea 
Published: July 2004

Abstract2‐methoxyestradiol (2ME2) is an endogenous metabolite of estradiol with estrogen‐receptor‐independent antitumor and antiangiogenic activity. We examined the effects of 2ME2 on the cellular proliferation of 8 human melanoma cell lines. We show that 2ME2 inhibited cell proliferation by inducing apoptosis and an arrest in the G2/M phase, and the mechanism of action involved microtubules, mitochondrial damage and caspase activation. In male SCID mice, 2ME2 was effective in reducing primary tumor weight and the number of liver metastases after intrasplenic injection of human melanoma cells. In the metastases, we found a significantly higher rate of apoptotic cells after 2ME2 treatment. These findings on the antitumor effect of 2ME2 in cell culture as well as in an animal model may have implications for designing alternative treatment options for patients with advanced malignant melanoma. © 2004 Wiley‐Liss, Inc.
DNA repair gene XRCC2 and XRCC3 polymorphisms and susceptibility to cancers of the upper aerodigestive tract
Authors: Benhamou Simone , Tuimala Jarno , Bouchardy Christine , Dayer Pierre , Sarasin Alain , Hirvonen Ari 
Published: July 2004

AbstractCigarette smoke can generate reactive oxygen species, which are capable of inducing double‐strand breaks (DSBs) in DNA. Polymorphisms in XRCC2 and XRCC3 genes, involved in DSBs repair pathways, may alter an individual's susceptibility to smoking‐related cancers. We investigated the effect of XRCC2 Arg188His and XRCC3 Thr241Met polymorphisms in cancer proneness in 121 oral/pharynx cancer cases, 129 larynx cancer cases and 172 noncancer controls, all Caucasian smokers. The XRCC2 His‐allele was associated with a significantly increased risk of pharyngeal cancer (OR=2.9, 95% CI: 1.3–6.2). No significant associations were observed between the XRCC3 Thr241Met polymorphism and overall risk of developing UADT cancers. However, quite opposite to the expectations, a reduced risk of supraglottic cancer was found for carriers of the XRCC3 Met variant allele (OR=0.3, 95% CI: 0.2–0.7). These findings provide evidence for the view that polymorphisms in DNA repair genes may modify individual susceptibility to smoking‐related cancers. © 2004 Wiley‐Liss, Inc.
Follicle stimulating hormone‐induced growth promotion and gene expression profiles on ovarian surface epithelial cells
Authors: Ji Qing , Liu Paul I. , Chen Peter K. , Aoyama Chisa 
Published: July 2004

AbstractEpidemiologic data have implicated reproductive follicle‐stimulating hormone (FSH) as a probable risk factor for ovarian cancer (OC) development. Although pituitary and sex hormones have been reported to regulate OC cell growth, no information is available on the influence of FSH on gene expression profiles during ovarian surface epithelial (OSE) cell proliferation. This study evaluated the effect of FSH treatment on cell proliferation of various OSE cell lines and gene expression profiles with FSH treatment. Follicle‐stimulating hormone receptor (FSHR) was found at higher expression at both transcriptional and protein levels in ovarian cancerous tissues compared to normal tissues, and FSH was shown to promote cell growth in 3 OSE cell lines. Furthermore, it was also found that overexpression of FSHR in Chinese hamster ovary (CHO) cells leads to cell proliferation. Using cDNA MicroArray analysis on MCV152 cells with FSH treatment, 91 genes were found upregulated and 68 genes downregulated for more than 2‐fold after FSH treatment. Most of the genes were related to metabolism, cell proliferation and oncogenes. Downregulated genes included tumor suppressor genes (RB1, BRCA1, BS69) and the genes related to cell proliferation control. Pathway analysis found that FSH activates certain important enzymes in sterol biosynthesis pathways. FSH‐induced gene expression profiles on MCV152 cells support the standing hypothesis that FSH is a probable risk factor for ovarian cancerous development. © 2004 Wiley‐Liss, Inc.
IL‐12 receptor‐mediated upregulation of FasL in human ovarian carcinoma cells
Authors: Gorelik Elieser , Edwards Robert P. , Feng Xin , Marrangoni Adele M. , Grandis Jennifer R. , Drenning Stephanie D. , Velikokhatnaya Lyudmila , Kwon Jeong‐Ah , Lokshin Anna E. 
Published: July 2004

AbstractThe expression and functions of IL‐12 receptor (IL‐12R) in human ovarian carcinoma cell lines have been investigated. Ovarian carcinoma cells express both the IL‐12Rβ1 and the IL‐12Rβ2 subunits. IL‐12R crosslinking resulted in phosphorylation of Tyk2, p44 (ERK1) and Akt kinases and activation of STATs 2, 3, 4 and 5. IL‐12 induced substantial upregulation of Fas ligand (FasL) surface expression in ovarian carcinoma cells paralleled by an increased ability to induce apoptosis in Jurkat cells and PHA‐activated lymphocytes. The induction of surface expression of FasL by IL‐12 was not due to upregulation of FasL gene expression, but resulted from downregulation of matrix metalloproteinases (MMPs)‐3 and ‐7 and consequently reduced cleavage of FasL from the cell surface. These findings bring new insights into the significance of IL‐12‐mediated effects in nonlymphoid cancer cells that might be of importance for improving the design of IL‐12‐based therapies for ovarian cancer. © 2004 Wiley‐Liss, Inc.
N‐glycosylation of CD97 within the EGF domains is crucial for epitope accessibility in normal and malignant cells as well as CD55 ligand binding
Authors: Wobus Manja , Vogel Björn , Schmücking Eike , Hamann Jörg , Aust Gabriela 
Published: July 2004

AbstractCD97 is an EGF‐TM7 receptor found on various carcinomas where expression levels correlate with dedifferentiation and tumor stage, smooth muscle cells and leukocytes. CD97 acts as an adhesion molecule by binding to its cellular ligand, CD55. In this study, we demonstrate that 2 immunodominant CD97 epitopes are not equally present in the various cell types. Differences were apparent in gastrointestinal tumors and smooth muscle cells where monoclonal antibodies (mAbs) to the first epidermal growth factor (EGF) domain (CD97EGF) showed a more restricted staining pattern than mAbs to the stalk region (CD97stalk). This discrepancy was not detectable in cultured gastrointestinal tumor cell lines. In fact, the selection of the CD97 mAb influences the result of clinical studies. Thus, we clarified the reason(s) for these differences in CD97 mAb staining on various cell types. We provide evidence that epitope accessibility for CD97EGF mAbs depends on N‐glycosylation. Immunoprecipitation of CD97 from the Colo 205 tumor cell line revealed the established 78 and 83 kDa products, while a 52 and 57 kDa band were obtained from smooth muscle cells. N‐glycosidase F reduced the size of CD97 in Colo 205 cells to 52–57 kDa. Culturing these cells with tunicamycin resulted in the same decrease in size and impaired CD97EGF mAb binding. As shown by site‐directed mutagenesis, deletion of the N‐glycosylation sites located within the EGF domains efficiently disturbed CD97EGF mAb immunoreactivity and, importantly, binding of CD55. In conclusion, CD97EGF epitope accessibility for mAbs and ligand binding is influenced by cell type‐specific N‐glycosylation. © 2004 Wiley‐Liss, Inc.
Single nucleotide polymorphism in the 5′ tandem repeat sequences of thymidylate synthase gene predicts for response to fluorouracil‐based chemotherapy in advanced colorectal cancer patients
Authors: Marcuello Eugenio , Altés Albert , del Rio Elisabeth , César Angeles , Menoyo Anna , Baiget Montserrat 
Published: July 2004

AbstractThymidylate synthase (TS) is the primary target of 5‐fluorouracil (5‐FU). A VNTR polymorphism in the TS promoter region is associated with the efficacy of 5‐FU‐based chemotherapy in colorectal cancer. A common G>C SNP at the 12th nucleotide of the second repeat in the TS*3 alleles has been recently described. The combination of SNP and VNTR allows the definition of 3 TS alleles: *2, *3G and *3C. The aim of our study was to evaluate the predictive value of clinical response and survival of these new defined TS alleles. TS genotypes of 89 patients diagnosed with metastatic colorectal cancer and undergoing 5‐FU‐based chemotherapy were carried out. The clinical outcome was evaluated according to the genotype (high expression genotype: *2R/*3G; *3C/*3G; *3G/*3G; and low expression genotype: *2R/*2R; *2R/*3C; *3C/*3C. A higher overall response was observed in the group of patients with a low expression genotype (p = 0.035). The probability of achieving a clinical response of patients with a low expression‐related genotype was 2.9 higher than that of the other group (95% CI = 1.03–5.6, p = 0.04). The median time to progression was 12 months and 9 months in the low and high expression groups, respectively (p = 0.07, log rank test). Overall survival was significantly longer in the low expression group. In this group the median OS was not achieved at 50 months of follow‐up in contrast to the 20 months observed in the high expression group (p = 0.03). TS genotype was an independent predictor of progression‐free and overall survival in the Cox regression models after adjustment to the other clinical variables. The selection of patients who are likely to respond to 5‐FU therapy may be considerably improved if the TS genotype were to include both the VNTR and the SNP located within the promoter region of the gene. © 2004 Wiley‐Liss, Inc.
Hollow‐fiber dispersion‐free extraction and stripping of Pb(II) in the presence of Cd(II) using D2EHPA under recirculating operation mode
Authors: Escobar Armando , Schimmel Keith A , de Gyves Josefina , de San Miguel Eduardo Rodríguez 
Published: July 2004

AbstractLead(II) and cadmium(II) solvent extraction (SX) with D2EHPA dissolved in heptane and kerosene from aqueous chloride media was studied. Extraction reaction stoichiometries and extraction equilibrium constants were evaluated. Application of a dispersion‐free membrane‐based extraction and stripping technique with two hollow‐fiber contactors under recirculating operation mode allowed a quantitative (>97%) removal of lead from the aqueous solution in the extraction module with a separation factor of 19 and a 62% recovery in the back‐extraction module with a separation factor of 6.3 after 7 h under optimum conditions. Mass‐transfer coefficients for the system were evaluated. Optimal conditions for transport and separation are reported and compared using SX and the membrane‐based technique. Copyright © 2004 Society of Chemical Industry
The effect of operational parameters on the performance of a bipolar trickle tower reactor
Authors: Trinidad Pedro , Walsh Frank C , Sheppard Sally A , Gillard Stephen P , Campbell Sheelagh A 
Published: July 2004

AbstractA bipolar trickle tower reactor (BTTR) (of 7.9 cm internal diameter and 75 cm length containing 57 layers, each layer having 30 carbon Raschig rings, each of 1.25 cm outside diameter) has been studied under a range of operational conditions. The batch recycle mode of operation has been used for the removal of Cu(II) ions (at an initial concentration of 50–200 ppm) from an acid sulfate solution (typically 3000 cm3) at 295 K. Non‐ideal flow and Peclet number values have been considered to establish the degree of deviation from ideal reactor flow models. Operational variables included the potential difference per layer (1.0–3.0 V), volumetric flow rate (8.3–50 cm3 s−1) and the effect of H2SO4 concentration (which increased conductivity and lowered pH) in the electrolyte. The reactor has been shown to be best suited to the treatment of a moderately high reactant concentration (eg 100–200 ppm) and low electrolyte conductivity. The final concentration can be as low as a few parts per million but the performance of the reactor (as judged by the current efficiency and the rate of concentration decay) markedly decreased as the dissolved metal ion concentration fell. Copyright © 2004 Society of Chemical Industry
The application of reticulated vitreous carbon rotating cylinder electrodes to the removal of cadmium and copper ions from solution
Authors: Reade Gavin W , Bond Peter , de Leon Carlos Ponce , Walsh Frank C 
Published: July 2004

AbstractThe removal of cadmium and cupric ions from 0.50 mol dm−3 Na2SO4 at pH 2 and 298 K was studied using a reticulated vitreous carbon (RVC) rotating cylinder electrode (RCE). The cathode was a 100 pores per linear inch porosity grade with a radius of 0.5 cm, a height of 1.2 cm and a volume of 0.94 cm3. The cathode was rotated a constant speed of 1500 rev min−1. A rate enhancement of approximately three times is reported for the removal of cupric ions from a chloride solution (0.05 mol dm−3 cupric ions in 0.1 mol dm−3 NaCl at pH 7) when compared with the analogous reaction in acid sulfate solutions (0.50 mol dm−3 Na2SO4 at pH 2). SEM images of the metal deposit morphology allow the morphology of the metal deposits to be characterised. The deposits showed incomplete coverage of the RVC surface and appreciable roughness developed with time due to dendritic growths. Copyright © 2004 Society of Chemical Industry
Synthesis and preliminary in vivo evaluation of 4‐[18F]fluoro‐N‐{2‐[4‐(6‐trifluoromethylpyridin‐2‐yl)piperazin‐1‐yl]ethyl}benzamide, a potential PET radioligand for the 5‐HT1A receptor
Authors: Vandecapelle M. , Dumont F. , De Vos F. , Strijckmans K. , Leysen D. , Audenaert K. , Dierckx R. A. , Slegers G. 
Published: July 2004

Abstract4‐Fluoro‐N‐{2‐[4‐(6‐trifluoromethylpyridin‐2‐yl)piperazin‐1‐yl]ethyl}benzamide is a full 5‐HT1A agonist with high affinity (pKi=9.3), selectivity and a c log P of 3.045. The corresponding PET radioligand 4‐[18F]fluoro‐N‐{2‐[4‐(6‐trifluoromethylpyridin‐2‐yl)piperazin‐1‐yl]ethyl}benzamide was synthesized by nucleophilic aromatic substitution on the nitro precursor. The fluorinating agent K[18F]F/Kryptofix 2.2.2 was both dried (9 min, 700 W) and incorporated in the precursor (5 min, 700 W) using a commercially available microwave oven. In a total synthesis time of 60 min, an overall radiochemical yield of 18% (SD=5, n=7, EOS) was obtained. Radiochemical purity was always higher than 99% and specific activity always higher than 81.4 GBq/µmol (2.2 Ci/µmol). Initial brain uptake in mice was 2.19% ID (5.47% ID/g, 2 min) but decreased rapidly (0.17% ID, 0.45% ID/g (60 min)). During the first 20 min p.i., radioactivity concentration of the brain was significantly higher than that of blood demonstrating good brain entry of the tracer. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis and radioiodination of 7‐(3′‐ammoniopropyl)‐7,8‐dicarba‐nido‐undecaborate(‐1), (ANC)
Authors: Ghirmai Senait , Malmquist Jonas , Lundquist Hans , Tolmachev Vladimir , Sjöberg Stefan 
Published: July 2004

AbstractDerivatives of nido‐carborate have potential use in tumour targeting as hydrophilic boron‐rich compounds for boron neutron capture therapy (BNCT) and as pendant groups for attachment of radiohalogens to tumour‐seeking molecules. For this purpose, functionalized derivatives of nido‐carborates that can be conjugated to biomolecules should be synthesized and evaluated. In this study, racemic 1, 7‐(3′‐ammoniopropyl)‐7,8‐dicarba‐nido‐undecaborate(‐1) (acronym ANC) was obtained by degradation of the corresponding aminopropyl‐o‐carborane, which was synthesized in three steps from 1‐tert‐butyldimethylsilyl‐2‐(3‐bromopropyl)‐o‐carborane, with sodium hydroxide in absolute ethanol. The racemate 1 was radioiodinated (125I) using the Chloramine‐T method. Radio‐TLC results showed that radiolabelling with 125I was achieved in a yield greater than 95%. Copyright © 2004 John Wiley & Sons, Ltd.