bluuebunny/crossref_metadata_2025_split huggingface dataset:
A conceptual hydrologic model for a forested Carolina bay depressional wetland on the Coastal Plain of South Carolina, USA
Authors: Pyzoha Jennifer E. , Callahan Timothy J. , Sun Ge , Trettin Carl C. , Miwa Masato 
Published: October 2007

AbstractThis paper describes how climate influences the hydrology of an ephemeral depressional wetland. Surface water and groundwater elevation data were collected for 7 years in a Coastal Plain watershed in South Carolina USA containing depressional wetlands, known as Carolina bays. Rainfall and temperature data were compared with water‐table well and piezometer data in and around one wetland. Using these data a conceptual model was created that describes the hydrology of the system under wet, dry, and drought conditions. The data suggest this wetland operates as a focal point for groundwater recharge under most climate conditions. During years of below‐normal to normal rainfall the hydraulic gradient indicated the potential for groundwater recharge from the depression, whereas during years of above‐normal rainfall, the hydraulic gradient between the adjacent upland, the wetland margin, and the wetland centre showed the potential for groundwater discharge into the wetland. Using high‐resolution water‐level measurements, this groundwater discharge condition was found to hold true even during individual rainfall events, especially under wet antecedent soil conditions. The dynamic nature of the hydrology in this Carolina bay clearly indicates it is not an isolated system as previously believed, and our groundwater data expand upon previous hydrologic investigations at similar sites which do not account for the role of groundwater in estimating the water budget of such systems. Copyright © 2007 John Wiley & Sons, Ltd.
Delineation of spatial redox zones using discriminant analysis and geochemical modelling in arsenic‐affected alluvial aquifers
Authors: Lee Jin‐Jing , Jang Cheng‐Shin , Wang Sheng‐Wei , Liang Chin‐Ping , Liu Chen‐Wuing 
Published: October 2007

AbstractThis study characterized the redox conditions in arsenic‐affected groundwater aquifers of the Lanyang plain, Taiwan. Discriminant analysis was adopted to delineate three redox zones (oxidative, transitional and reductive zones) in different aquifers and yielded 92·3% correctness on groundwater quality data. Arsenic is mainly distributed in the reductive zone, and arsenic distribution in the shallow aquifer is mainly affected by surface activities. According to PHREEQC modelling results, possible mechanisms for arsenic release to groundwater in Lanyang plain are explored. Arsenic released to groundwater in the oxidative zone (zone 1) is primarily caused by the oxidations of arsenic‐bearing pyrite minerals, and arsenate is the predominant species. While the reductive dissolution of Fe‐oxides are responsible for the high arsenic concentration found in the transitional and reductive zones (zones 2 and 3), arsenite is the predominant species. The reduction potential of groundwater rises as the depths and zones increase. Some sulphates may be reduced to form sulphide ions, which then react with arsenic to form arseno‐sulphide deposits (such as realgar, orpiment) and then slightly lower groundwater arsenic concentrations. A conceptual diagram which summarized the possible release processes of arsenic in different redox zones along groundwater flow in Lanyang plain is postulated. Arsenic‐bearing pyrite and arsenopyrite (FeAsS) are oxidized as they are exposed to the infiltrated oxygenated rainwater, releasing soluble arsenate Fe(II) and SO42− into zone 1. The dissolution of arsenic‐rich Fe‐oxides due to the onset of reducing conditions in zones 2 and 3 is responsible for the mobility of arsenic and likely to be the primary mechanism of arsenic release to groundwater in the Lanyang plain Copyright © 2007 John Wiley & Sons, Ltd.
Estimation of suspended sediment loads and delivery in an incised upland headwater catchment, south‐eastern Australia
Authors: Smith Hugh G. 
Published: October 2007

AbstractHistorically upland headwater catchments in south‐eastern Australia have undergone extensive gully erosion that has removed large amounts of sediment to lowlands. Recent research suggests these upland areas may continue to dominate fine sediment loads in lowland rivers. Improved understanding of sediment transfer through upland headwater catchments may have implications for interpreting downstream sediment supply. In this study a nested catchment design was utilized to examine suspended sediment yields and delivery from a small tributary sub‐catchment (1·64 km2) to the study catchment outlet (53·5 km2). Monitoring of suspended sediment concentration and discharge was undertaken for a period of nearly two years and used to estimate suspended sediment loads. Estimated total suspended sediment exports over the period of monitoring were 24·16 t from the sub‐catchment and 550·3 t from the catchment, which are generally less than previous reported small catchment yields in south‐eastern Australia. The extent of sediment delivery was examined using between‐site ratios of specific sediment yield per unit area and incised channel length. Sediment delivery was high under average rainfall conditions, but seasonally dependent. Both suspended sediment yields and the extent of delivery peaked over spring months, supplemented by remobilization of sediment stored during summer months in the main catchment channel. The findings of this study suggest much of the suspended sediment exported from small incised upland sub‐catchments (1–2 km2) may be delivered to downstream reaches under average rainfall conditions, which, in conjunction with the findings of previous research supports the potential importance of contributions from these areas to suspended sediment loads in lowland rivers during high flow periods. Copyright © 2007 John Wiley & Sons, Ltd.
Cannabinoids in pancreatic cancer: Correlation with survival and pain
Authors: Michalski Christoph W. , Oti Florian E. , Erkan Mert , Sauliunaite Danguole , Bergmann Frank , Pacher Pal , Batkai Sandor , Müller Michael W. , Giese Nathalia A. , Friess Helmut , Kleeff Jörg 
Published: October 2007

AbstractCannabinoids exert antiproliferative properties in a variety of malignant tumors, including pancreatic ductal adenocarcinoma (PDAC). In our study, we quantitatively evaluated the immunoreactivity for cannabinoid‐1 (CB1) and cannabinoid‐2 (CB2) receptors as well as for the endocannabinoid metabolizing enzymes fatty acid amide hydrolase (FAAH) and monoacyl glycerol lipase (MGLL). Furthermore, quantitative real‐time RT‐PCR for CB1, CB2, FAAH and MGLL in normal pancreas and pancreatic cancer tissues was performed. Levels of endocannabinoids were determined by liquid chromatography/mass spectrometry. Immunoreactivity scores and QRT‐PCR expression levels were correlated with the clinico‐pathological (TNM, survival, pain) status of the patients. Evaluation of endocannabinoid levels revealed that these remained unchanged in PDAC compared to the normal pancreas. Patients with high CB1 receptor levels in enlarged nerves in PDAC had a lower combined pain score (intensity, frequency, duration; p = 0.012). There was a significant relationship between low CB1 receptor immunoreactivity or mRNA expression levels (p = 0.0011 and p = 0.026, respectively), or high FAAH and MGLL cancer cell immunoreactivity (p = 0.036 and p = 0.017, respectively) and longer survival of PDAC patients. These results are underlined by a significant correlation of high pain scores and increased survival (p = 0.0343). CB2 receptor immunoreactivity, CB2 receptor, FAAH and MGLL mRNA expression levels did not correlate with survival. Therefore, changes in the levels of endocannabinoid metabolizing enzymes and cannabinoid receptors on pancreatic cancer cells may affect prognosis and pain status of PDAC patients. © 2007 Wiley‐Liss, Inc.
E7080, a novel inhibitor that targets multiple kinases, has potent antitumor activities against stem cell factor producing human small cell lung cancer H146, based on angiogenesis inhibition
Authors: Matsui Junji , Yamamoto Yuji , Funahashi Yasuhiro , Tsuruoka Akihiko , Watanabe Tatsuo , Wakabayashi Toshiaki , Uenaka Toshimitsu , Asada Makoto 
Published: October 2007

AbstractE7080 is an orally active inhibitor of multiple receptor tyrosine kinases including VEGF, FGF and SCF receptors. In this study, we show the inhibitory activity of E7080 against SCF‐induced angiogenesis in vitro and tumor growth of SCF‐producing human small cell lung carcinoma H146 cells in vivo. E7080 inhibits SCF‐driven tube formation of HUVEC, which express SCF receptor, KIT at the IC50 value of 5.2 nM and it was almost identical for VEGF‐driven one (IC50 = 5.1 nM). To assess the role of SCF/KIT signaling in tumor angiogenesis, we evaluated the effect of imatinib, a selective KIT kinase inhibitor, on tumor growth of H146 cells in nude mice. Imatinib did not show the potent antitumor activity in vitro (IC50 = 2,200 nM), because H146 cells did not express KIT. However, oral administration of imatinib at 160 mg/kg clearly slowed tumor growth of H146 cells in nude mice, accompanied by decreased microvessel density. Oral administration of E7080 inhibited tumor growth of H146 cells at doses of 30 and 100 mg/kg in a dose‐dependent manner and caused tumor regression at 100 mg/kg. While anti‐VEGF antibody also slowed tumor growth, it did not cause tumor regression. These results indicate that KIT signaling has a role in tumor angiogenesis of SCF‐producing H146 cells, and E7080 causes regression of H146 tumors as a result of antiangiogenic activity mediated by inhibition of both KIT and VEGF receptor signaling. E7080 may provide therapeutic benefits in the treatment of SCF‐producing tumors. © 2007 Wiley‐Liss, Inc.
Noggin blocks invasive growth of murine B16‐F1 melanoma cells in the optic cup of the chick embryo
Authors: Busch Christian , Drews Ulrich , Eisele Stefan R. , Garbe Claus , Oppitz Matthias 
Published: October 2007

AbstractMelanoma cells originate from the neural crest and are characterized by high migratory potential and invasive growth. After transplantation into the neural tube of the chick embryo, melanoma cells spontaneously emigrate along the neural crest pathways without tumor formation or malignant growth. This emigration depends on the constitutive over‐expression of bone morphogenetic protein‐2 (BMP‐2) and can be ablated by the BMP‐antagonist noggin. When transplanted into the embryonic optic cup, melanoma cells invade the host tissue and form malignant tumors. Here, we asked if the invasive growth of melanoma cells in the optic cup could be influenced by BMP‐2 or noggin. Mouse B16‐F1 cells were grown as aggregates, treated with BMP‐2 or noggin during aggregation and transplanted into the optic cup of 3‐day chick embryos. After 3 days of subsequent incubation, embryos were evaluated for melanoma cell invasiveness. Immunohistochemical examination revealed that untreated and BMP‐2‐treated melanoma cells had grown malignantly into the host tissue. However, noggin pretreatment of the aggregates had blocked melanoma cell invasiveness and tumor formation. We conclude that invasive growth of melanoma cells in vivo is BMP‐dependent and can be ablated by noggin, thus rendering noggin a promising agent for the treatment of BMP‐over‐expressing melanoma. © 2007 Wiley‐Liss, Inc.
Caveolin‐1 secreting LNCaP cells induce tumor growth of caveolin‐1 negative LNCaP cells in vivo
Authors: Bartz René , Zhou Jian , Hsieh Jer‐Tsong , Ying Yunshu , Li Weiping , Liu Pingsheng 
Published: October 2007

AbstractCaveolin‐1 (Cav‐1) was originally identified as a structural protein of caveolae, which is a plasma membrane domain that regulates a variety of signaling pathways involved in cell growth and migration. Here, we show that expression of Cav‐1 in the Cav‐1‐deficient human prostate cancer cell line LNCaP both stimulates cell proliferation and promotes tumor growth in nude mice. Unexpectedly, Cav‐1 expressing LNCaP (LNCaPCav‐1) cells injected into one side of a nude mouse promoted tumor growth of Cav‐1 negative LNCaP cells injected on the contralateral side of the same animal. The LNCaP tumors were positive for Cav‐1, however, this signal was not caused by migrated LNCaPCav‐1 cells, but we show that this Cav‐1 was secreted by the LNCaPCav‐1 tumors. We demonstrate that conditioned media from LNCaPCav‐1 cells contained Cav‐1 that was associated with a lipoprotein particle ranging in size from 15 to 30 nm and a density similar to high density lipoprotein particle. These results suggest that LNCaPCav‐1 cells secreting Cav‐1 particle produce an endocrine factor that stimulates tumor growth. © 2007 Wiley‐Liss, Inc.
Inhibitory effects of olive oil phenolics on invasion in human colon adenocarcinoma cells in vitro
Authors: Hashim Yumi Z.H‐Y. , Rowland Ian R. , McGlynn Hugh , Servili Maurizio , Selvaggini Roberto , Taticchi Agnese , Esposto Sonia , Montedoro GianFrancesco , Kaisalo Leena , Wähälä Kristiina , Gill Chris I.R. 
Published: October 2007

AbstractStudies in human, animal and cellular systems suggest that phenols from virgin olive oil are capable of inhibiting several stages in carcinogenesis, including metastasis. The invasion cascade comprises cell attachment to extracellular matrix components or basement membrane, degradation of basement membrane by proteolytic enzymes and migration of cells through the modified matrix. In the present study, we investigated the effect of phenolics extracted from virgin olive oil (OVP) and its main constituents: hydroxytyrosol (3,4‐dihydroxyphenylethanol), tyrosol (p‐hydroxyphenylethanol), pinoresinol and caffeic acid. The effects of these phenolics were tested on the invasion of HT115 human colon carcinoma cells in a Matrigel invasion assay. OVP and its compounds showed different dose‐related anti‐invasive effects. At 25 μg/ml OVP and equivalent doses of individual compounds, significant anti‐invasive effects were seen in the range of 45–55% of control. Importantly, OVP, but not the isolated phenolics, significantly reduced total cell number in the Matrigel invasion assay. There were no significant effects shown on cell viability, indicating the reduction of cell number in the Matrigel invasion assay was not due to cytotoxicity. There were also no significant effects on cell attachment to plastic substrate, indicating the importance of extracellular matrix in modulating the anti‐invasive effects of OVP. In conclusion, the results from this study indicate that phenols from virgin olive oil have the ability to inhibit invasion of colon cancer cells and the effects may be mediated at different levels of the invasion cascade. © 2007 Wiley‐Liss, Inc.
MYCN regulates oncogenic MicroRNAs in neuroblastoma
Authors: Schulte Johannes H. , Horn Sebastian , Otto Tobias , Samans Birgit , Heukamp Lukas C. , Eilers Ursula‐Christa , Krause Michael , Astrahantseff Kathy , Klein‐Hitpass Ludger , Buettner Reinhard , Schramm Alexander , Christiansen Holger , Eilers Martin , Eggert Angelika , Berwanger Bernd 
Published: October 2007

AbstractMYCN amplification is a common feature of aggressive tumour biology in neuroblastoma. The MYCN transcription factor has been demonstrated to induce or repress expression of numerous genes. MicroRNAs (miRNA) are a recently discovered class of short RNAs that repress translation and promote mRNA degradation by sequence‐specific interaction with mRNA. Here, we sought to analyse the role of MYCN in regulation of miRNA expression. Using a miRNA microarray containing 384 different miRNAs and a set of 160 miRNA real‐time PCR assays to validate the microarray results, 7 miRNAs were identified that are induced by MYCN in vitro and are upregulated in primary neuroblastomas with MYCN amplification. Three of the seven miRNAs belong to the miR‐106a and miR‐17 clusters, which have previously been shown to be regulated by c‐Myc. The miR‐17–92 polycistron also acts as an oncogene in haematopoietic progenitor cells. We show here that miR‐221 is also induced by MYCN in neuroblastoma. Previous studies have reported miR‐221 to be overexpressed in several other cancer entities, but its regulation has never before been associated with Myc. We present evidence of miRNA dysregulation in neuroblastoma. Additionally, we report miRNA induction to be a new mechanism of gene expression downregulation by MYCN. © 2007 Wiley‐Liss, Inc.
Modifying network chemistry in thiol‐acrylate photopolymers through postpolymerization functionalization to control cell‐material interactions
Authors: Rydholm Amber E. , Held Nicole L. , Benoit Danielle S.W. , Bowman Christopher N. , Anseth Kristi S. 
Published: October 2007

AbstractThiol‐acrylate photopolymers often contain pendant, unreacted thiol groups even following complete reaction of the acrylate functional groups. The results presented herein demonstrate a high throughput method for quantifying pendant thiol group concentrations using FTIR spectra of thiol‐acrylate microspot arrays. Using this technique, more than 25% of the original thiol groups were detected as pendant groups in microspots made from monomer solutions containing at least 40 mol % thiol functional groups. Subsequent modification reactions allowed postpolymerization tailoring of the network chemistry. The extent of modification was controlled by the concentration of the pendant thiols (ranging from 0.01 to 0.4M) and the duration of the modification reaction (0–10 min for photocoupling reactions, 0–24 h for Michael‐type addition reactions). Further, when photocoupling was used to modify the networks, spatial and temporal control of the light exposure facilitated the formation of chemical patterns on the surface and throughout the material. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Application of porous glycosaminoglycan‐based scaffolds for expansion of human cord blood stem cells in perfusion culture
Authors: Cho Cheul H. , Eliason James F. , Matthew Howard W.T. 
Published: October 2007

AbstractIn vitro expansion of hematopoietic stem cells (HSCs) has been employed to obtain sufficient numbers of stem cells for successful engraftment after HSC transplantation. A three‐dimensional perfusion bioreactor system with a heparin‐chitosan scaffold was designed and evaluated for its capability to support maintenance and expansion of HSCs. Porous chitosan scaffolds were fabricated by a freeze‐drying technique and N‐desulfated heparin was covalently immobilized within the scaffolds using carbodiimide chemistry. CD34+ HSCs isolated from umbilical cord blood by immunomagnetic separation were cultured within the porous scaffold in a perfusion bioreactor system. Control cultures were maintained on dishes coated with similar heparin‐chitosan films. Oxygen uptake was measured during the culture period. After 7 days of culture, scaffolds were harvested for analysis. Cellular phenotype and HSC characteristics were evaluated via flow cytometry and colony forming unit assays. The results indicate good cell retention and proliferation within the perfused scaffolds. Oxygen consumption in the perfusion bioreactor system increased continuously during the culture, indicating steady cell growth. Cells from the perfused scaffold cultures showed higher percentages of primitive progenitors and exhibited superior colony forming unit performance as compared to cells from static cultures. In addition, perfusion culture at low oxygen (5%) enhanced the expansion of CD34+ cells and colony‐forming activity compared to high oxygen (19%) cultures. The results suggest that perfusion culture of cord blood CD34+ cells under bone marrow‐like conditions enhances HSC expansion compared to static cultures. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
The electrochemical behavior of nitinol in simulated physiological solutions
Authors: Pound Bruce G. 
Published: October 2007

AbstractThe electrochemical behavior of nitinol in simulated human bile and phosphate‐buffered saline (PBS) was examined using electrochemical impedance spectroscopy. In addition, cyclic potentiodynamic polarization tests were performed in the simulated bile and salt‐only bile, and the results compared with those obtained previously in PBS. The potentiodynamic tests showed that electropolishing was effective in providing nitinol with a high resistance to pitting corrosion in the bile solutions, as found in PBS. Differences between the breakdown potential and the corrosion potential indicated that mechanically polished nitinol should be more susceptible to pitting corrosion in simulated bile than in the salt‐only bile and PBS. The impedance spectra showed near‐capacitive behavior in both PBS and simulated bile, and the data could be fitted by a parallel resistance–capacitance (as a constant phase element) circuit associated with the passive oxide film. The thickness of the oxide was determined from the capacitive component and found to be consistent with surface analytical results reported in the literature. Resistivities obtained from resistance values indicated that compositional features of the oxide were similar for PBS and simulated bile. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Biological activity of recombinant human growth factors released from biocompatible bone implants
Authors: Ziegler Joerg , Anger Dominique , Krummenauer Frank , Breitig Dieter , Fickert Stefan , Guenther Klaus‐Peter 
Published: October 2007

AbstractThe present investigation was performed to study the bioactivity of osteoinductive and osteoproliferative growth factors after release from biocompatible bone implants. Three types of porous carriers were used in this study: hydroxyapatite, alpha tricalcium phosphate, and a neutralized glass ceramic. Implants were loaded with recombinant human bone morphogenetic protein 2 (rh‐BMP‐2) and recombinant human basic fibroblast growth factor (rh‐bFGF) in a concentration of 2 μg/150 μL PBS each. The released growth factors were then applicated into SAOS‐2‐cell cultures. After 3, 5, and 7 days cell differentiation was measured by the activity of alkaline phosphatase (ALP), cell proliferation by using a MTT assay as well as a cell counter. Rh‐BMP‐2 released during the first hour from the scaffolds led to a significant increase of the activity of ALP in the incubated SAOS‐2‐cell culture after 3, 5, and 7 days. However, the incubation with rh‐BMP‐2 released after 24 h was not found to increase the expression of ALP. The incubation of cell cultures with rh‐bFGF released during the first hour led to a significant increase of cell number and of extinction in the MTT assay, whereas this increase was not observed after incubation with rh‐bFGF released after 24 h. The in vitro measured biological activity of released growth factors from the surface of synthetic implants is time‐depending. If prolonged osteoinductive and osteoproliferative potency of growth factors is desired, a modified application technique should be chosen to stabilize those proteins. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008