bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct Electrochemistry of Myoglobin in a Nafion‐Ionic Liquid Composite Film Modified Carbon Ionic Liquid Electrode
Authors: Sun Wei , Li Xiaoqing , Jiao Kui
Published: February 2009

In this paper two kinds of ionic liquids (ILs) were used for the construction of a myoglobin (Mb) electrochemical biosensor. Firstly a hydrophilic ionic liquid of 1‐ethyl‐3‐methylimidazolium tetrafluoroborate (EMIMBF4) was used as binder to prepare a carbon ionic liquid electrode (CILE), then a Nafion and hydrophobic ionic liquid of 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIMPF6) composite film was applied on the surface of the CILE. The direct electrochemistry of Mb in the Nafion‐BMIMPF6/CILE was achieved with the cathodic and anodic peak potentials located at −0.345 V and −0.213 V (vs. SCE). The formal potential (E°′) was located at −0.279 V, which was the characteristic of Mb FeIII/FeII redox couples. The electrochemical behaviors of Mb in the Nafion‐ionic liquid composite film modified CILE were carefully investigated. The Mb modified electrode showed good electrocatalytic behaviors to the reduction of trichloroacetic acid (TCA) and NaNO2. Based on the Nafion‐BMIMPF6/Mb/CILE, a new third generation reagentless biosensor was constructed.
Simultaneous Quantification of Heavy Metals Using a Solid State Potentiometric Sensor Array
Authors: Gismera Ma Jesús , Arias Sandra , Sevilla Ma Teresa , Procopio Jesús R.
Published: February 2009

A potentiometric sensor array of four nonspecific electrodes with solid‐state membranes is developed and tested for simultaneous analysis of copper(II), mercury(II), and silver(I) ions. The cross‐sensitivity responses of the sensors for these ions are evaluated. The array potentiometric signals are processed by partial least‐squares regression (PLS) and back propagation artificial neural networks (ANN) to determinate analyte concentrations. The ANN configuration is optimized and two different training algorithms of the ANN are also evaluated. Best results are obtained when the potentiometric sensors are activated and the data are processed using ANN and the gradient descent adaptive algorithm. The system is used to quantify these heavy metals in synthetic samples and in dental amalgams with successful results.
Thionicotinamide SAM on Gold: Adsorption Studies and Electroactivity
Authors: de Freitas Paulo Tércio , de Oliveira Pinheiro Solange , Da Silva Maria Aparecida S. , de França Lopes Luiz Gonzaga , Pinheiro Lucidalva S. , Aquino Gil F. A. , Temperini Márcia Laudelina Arruda , de Lima Neto Pedro , Diógenes Izaura Cirino Nogueira
Published: February 2009

STM and impedance results of the self‐assembled monolayer (SAM) formed with thionicotinamide (TNA) on gold indicate the presence of defects that increase with the immersion time of the electrode in the TNA solution affecting the SAM electroactivity toward the electron transfer reaction of the cytochrome c metalloprotein and [Fe(CN)6]4− and [Ru(NH3)6]3+ complexes. It was observed that this electroactivity was also affected by the pH of the electrolyte solution. SERS and STM data indicate sulfur coordination to the surface with contribution of the NH2 group. From the dependence of the TNA surface coverage on the temperature and concentration in solution, thermodynamic parameters of adsorption were determined.
Green Approaches to Field Nitrate Analysis: An Electroanalytical Perspective
Authors: Desai Radha , Marti Villalba Maria , Lawrence Nathan S. , Davis James
Published: February 2009

The different approaches that have been taken in the development of analytical methods for the determination of nitrate within the field are reviewed. The emphasis has been placed on providing a critical appraisal of the chemistry that underpins current commercial systems and the need to remove the dependence on heavy metal and concentrated acid components. The search for more environmentally acceptable and user friendly systems has long been pursued and the present communication seeks to explore the recent development in portable testing technologies and how they might evolve in the future. In particular, the role of electrochemical techniques in the latter are investigated and their potential application compared and contrasted with the more traditional wet chemical detection strategies.
Localized Deposition of Chitosan as Matrix for Enzyme Immobilization
Authors: Chen Po‐Chung , Chen Richie L. C. , Cheng Tzong‐Jih , Wittstock G.
Published: February 2009

A local electrodeposition method was developed for chitosan by exploiting a pH gradient between a macroscopic electrode (the support) and a much smaller counter electrode. The deposition was confined either by using the direct mode of scanning electrochemical microscopy (SECM) or by performing the deposition in channels of a microfluidic network. The roughness was characterized by noncontact scanning force microscopy. The availability of amino groups at the surface of the microstructures was visualized after labeling by confocal laser scanning microscopy. The enzyme glucose oxidase could be entrapped during the electrochemical deposition and showed activity as seen by SECM images.
Single‐nucleotide polymorphism typing based on pyrosequencing chemistry and acryl‐modified glass chip
Authors: Huang Huan , Wu Haiping , Xiao Pengfeng , Zhou Guohua
Published: February 2009

A new method (termed as “chip‐BAMPER” (bioluminometric assay coupled with modified primer extension reactions)) for single‐nucleotide polymorphism (SNPs) genotyping was developed by pyrosequencing chemistry coupled with hydrogel chip immobilized with single‐stranded target DNAs. The method is based on allele‐specific extension reaction, which is switched by the base type in the 3′ end of allele‐specific primers. A genotype is determined by comparing the light intensity from a pair of gel pads, and the specificity is improved by introducing an artificially mismatched base at the third position upstream from the 3′ end of the allele‐specific primer. The big problem of chip‐BAMPER is the ultra‐high background of the detection mixture because apyrase could not be used. Here, we successfully prepared and used beaded apyrase, which can be removed from the detection mixture before sample typing, to decrease the high background due to adenosine 5′‐triphosphate and inorganic pyrophosphate or sodium pyrophosphate decahydrate contamination. Unlike gel‐based pyrosequencing, chip‐BAMPER is highly sensitive because many bases are extended at a time in one extension reaction. Usually, less than 0.25 μL of PCR products can give a successful genotyping. To evaluate the method, four SNPs, OLR1‐C15577T, OLR1‐C14417G, PPARG‐Pro12Ala, and PPARG‐C2821T, were detected. To avoid the crosstalk between two adjacent spots in a gel‐chip, mineral oil was dispensed to coat the gel‐chip for physically separating two spots. It is shown that this new strategy of SNP typing based on the acryl‐modified glass chip is highly sensitive, simple, inexpensive, and easy to be automated. It can be used for various applications of DNA analysis at a relative high‐throughput.
Development and evaluation of a model for soil–air fluidized bed rheological behavior
Authors: Fox David M. , Lee Joon Sang
Published: February 2009

The ground vehicle mine blast mitigation problem represents a research topic that has recently been generating a very high level of interest and activity. Many aspects of the physics of the problem have been extensively researched. One area that has been neglected, however, is that aspect of the blast threat that relates to the rheology and flow, subsequent to ignition of the explosive, of the relatively energetic mixture of air and soil, sometimes referred to as ejecta.

Methods developed for the study of fluidized beds that are used in, e.g. the chemical and power generation process industries, were adapted in order to more clearly define the rheology of air–glass bead mixtures and also of air–soil mixtures that comprise the ejecta. Continuity and momentum balance equations developed for fluidized beds were adapted, using physical properties of glass beads and soils, into a form relates to the properties of mine blast ejecta.

These equations were then discretized and solved, for a relatively simple geometry, in order to validate the model and gain a general sense of the flow behavior of particle–air blends. Parametric studies were performed to estimate the variation of the rheology of the air–particle mixtures as a function of the particle diameter and the sphericity of the particles. Finally, the flow properties of a couple of real soils were investigated via application of the two‐phase flow model. Copyright © 2009 John Wiley & Sons, Ltd.
Moving mesh methods for Boussinesq equation
Authors: Wan‐Lung Lee , Tan Zhijun
Published: February 2009

The Boussinesq equation is a challenging problem both analytically and numerically. Owing to the complex dynamic development of small scales and the rapid loss of solution regularity, the Boussinesq equation pushes any numerical strategy to the limit. With uniform meshes, the amount of computational time is too large to enable us to obtain useful numerical approximations. Therefore, developing effective and robust moving mesh methods for these problems becomes necessary. In this work, we develop an efficient moving mesh algorithm for solving the two‐dimensional Boussinesq equation. Our moving mesh algorithm is an extension of Tang and Tang (SIAM J. Numer. Anal. 2003; 41:487–515) for hyperbolic conservation laws and Zhang and Tang (Commun. Pure Appl. Anal. 2002; 1:57–73) for convection‐dominated equations. Several numerical fluxes (Riemann Solvers and Numerical Methods for Fluid Dynamics: A Practical Introduction (2nd edn). Springer: Berlin, 1999; WASCOM 99”: 10th Conference on Waves and Stability in Continuous Media, Porto Ercole, Italy, 1999; 257–264; High‐order Methods for Computational Physics. Springer: Berlin, 1999; 439–582; J. Sci. Comput. 1990; 5:127–149; SIAM J. Numer. Anal. 2003; 41:487–515; Commun. Pure Appl. Anal. 2002; 1:57–73) are also discussed. Numerical results demonstrate the advantage of our moving mesh method in resolving the small structures. Copyright © 2009 John Wiley & Sons, Ltd.
Flow division at a channel crossing with subcritical or supercritical flow
Authors: Li C. W. , Zeng C.
Published: February 2009

The passage of an extreme storm over an urban area can lead to the flooding of the streets if the rainfall intensity exceeds the design value and/or the drainage system is not functional. The study of flow distribution in street networks thus is important for the design of flood protection measures. The flow distribution is affected by the junction flow characteristics, inflow discharges and downstream water depths. To reduce the degree of empiricism, a 3D Reynolds‐averaged Navier–Stokes equations model has been implemented in this study to investigate the flow phenomena in a cross junction. The Spalart–Allmaras model is used for turbulence closure. The numerical model utilizes the split‐operator approach, in which the advection, diffusion and pressure propagations are solved separately. The numerical model predicts accurately the flow distribution in a channel crossing under different subcritical flow conditions, for which experimental data are available. Recirculation zones exist at both the downstream channels and the associated contraction coefficient varies linearly with the ratio of the discharges at the two inlets. Secondary currents are apparent for the flow with strong asymmetric outlet conditions. Under supercritical inflow conditions, the model reproduces the hydraulic jump and hydraulic drop phenomena and predicts accurately the relationship between the input power ratio and the outflow discharge ratio of the street crossing. Copyright © 2009 John Wiley & Sons, Ltd.
Increase in gene dosage is a mechanism of HIF‐1α constitutive expression in head and neck squamous cell carcinomas
Authors: Secades Pablo , Rodrigo Juan Pablo , Hermsen Mario , Alvarez Cesar , Suarez Carlos , Chiara María‐Dolores
Published: February 2009

The HIF‐1α protein plays a key role in the cellular response to hypoxia via transcriptional regulation of genes involved in erythropoiesis, angiogenesis, and metabolism. Overexpression of HIF‐1α is commonly found in solid tumors in significant association with increased patient mortality and resistance to therapy. The predominant mode of HIF‐1α regulation by hypoxia occurs at the level of protein stability. In addition to hypoxia, HIF‐1α protein stability and synthesis is regulated by nonhypoxic signals such as inactivation of tumor suppressors and activation of oncogenes. Here, we show that an increase in gene dosage may contribute to HIF‐1α mRNA and protein overexpression in a nonhypoxic environment in head and neck squamous cell carcinomas (HNSCC). Increased HIF‐1α gene dosage was found in one out of five HNSCC‐derived cell lines and three out of 27 HNSCC primary tumors. Significantly, increased gene dosage in those samples was associated with high HIF‐1α mRNA and protein levels. Normoxic overexpression of HIF‐1α protein in HNSCC‐derived cell lines was also paralleled by higher expression levels of HIF‐1α target genes. Array CGH analysis confirmed the copy number increase of HIF‐1α gene and revealed that the gene is contained within a region of amplification at 14q23‐q24.2 both in the cell line and primary tumors. In addition, FISH analysis revealed the presence of 11–13 copies on a tetraploid background in SCC2 cells. These data suggest that increased HIF‐1α gene dosage is a mechanism of HIF‐1α protein overexpression in HNSCC that possibly prepares the cells for a higher activity in an intratumoral hypoxic environment. © 2009 Wiley‐Liss, Inc.
Genomic imbalances in rhabdomyosarcoma cell lines affect expression of genes frequently altered in primary tumors: An approach to identify candidate genes involved in tumor development
Authors: Missiaglia Edoardo , Selfe Joanna , Hamdi Mohamed , Williamson Daniel , Schaaf Gerben , Fang Cheng , Koster Jan , Summersgill Brenda , Messahel Boo , Versteeg Rogier , Pritchard‐Jones Kathy , Kool Marcel , Shipley Janet
Published: February 2009

Rhabdomyosarcomas (RMS) are the most common pediatric soft tissue sarcomas. They resemble developing skeletal muscle and are histologically divided into two main subtypes; alveolar and embryonal RMS. Characteristic genomic aberrations, including the PAX3‐ and PAX7‐FOXO1 fusion genes in alveolar cases, have led to increased understanding of their molecular biology. Here, we determined the effect of genomic copy number on gene expression levels through array comparative genomic hybridization (CGH) analysis of 13 RMS cell lines, confirmed by multiplex ligation‐dependent probe amplification copy number analyses, combined with their corresponding expression profiles. Genes altered at the transcriptional level by genomic imbalances were identified and the effect on expression was proportional to the level of genomic imbalance. Extrapolating to a public expression profiling dataset for 132 primary RMS identified features common to the cell lines and primary samples and associations with subtypes and fusion gene status. Genes identified such as CDK4 and MYCN are known to be amplified, overexpressed, and involved in RMS tumorigenesis. Of the many genes identified, those with likely functional relevance included CENPF, DTL, MYC, EYA2, and FGFR1. Copy number and expression of FGFR1 was validated in additional primary material and found amplified in 6 out of 196 cases and overexpressed relative to skeletal muscle and myoblasts, with significantly higher expression levels in the embryonal compared with alveolar subtypes. This illustrates the ability to identify genes of potential significance in tumor development through combining genomic and transcriptomic profiles from representative cell lines with publicly available expression profiling data from primary tumors. © 2009 Wiley‐Liss, Inc.
Association analysis of the COMT/MTHFR genes and geriatric depression: An MRI study of the putamen
Authors: Pan Chih‐Chuan , McQuoid Douglas R. , Taylor Warren D. , Payne Martha E. , Ashley‐Koch Allison , Steffens David C.
Published: February 2009

Objective

Catechol‐O‐Methyltransferase (COMT) and Methylenetetrahydrofolate reductase (MTHFR) had been reported to relate to depression but with inconsistent results. The basal ganglia are also important in the pathophysiology of affective disorder via connections with limbic system and prefrontal cortex. The authors examined the relationship between an interaction of COMT/MTHFR polymorphisms and volumes of putamen in depressed and nondepressed elders.

Methods

Participants included 170 depressed and 83 nondepressed subjects aged 60 years or older. Subjects completed cross‐sectional assessments, including clinical evaluation, brain magnetic resonance imaging (MRI) scan, and COMT Val158Met and MTHFR C677T genotyping. Putamen volumes were measured using 1.5‐Tesla whole‐body MRI system. Statistical models examined the relationship between COMT/MTHFR genotype, proportional volumes of putamen and depression while controlling for age and sex.

Results

After controlling for covariates, among depressed subjects with MTHFR C/C, both the right and left putamen had smaller volumes as the number of COMT 158Val increased. The left putamen volumes of depressed subjects with COMT Met/Met were smaller as the number of MTHFR 677T increased compared to nondepressed subjects.

Conclusions

Our findings do not support a major role for COMT or MTHFR alone. However, an epigenetic interaction of COMT Val158Met and MTHFR C677T polymorphisms may contribute to putamen volumes differences between depressed and nondepressed subjects. Further studies with a larger sample size are necessary to support a genetically based role for basal ganglia structures in the etiopathogenesis of depression. Copyright © 2009 John Wiley & Sons, Ltd.
Investigation of dopamine receptors in susceptibility to behavioural and psychological symptoms in Alzheimer's disease
Authors: Pritchard Antonia L. , Ratcliffe Laura , Sorour Eman , Haque Sayeed , Holder Roger , Bentham Peter , Lendon Corinne L.
Published: February 2009

Objective

Alzheimer's disease (AD) patients commonly suffer from behavioural and psychological symptoms of dementia (BPSD). A genetic component to the development of BPSD in AD has been supported. Polymorphisms within dopamine receptors DRD1, DRD2, DRD3 and DRD4 have previously been investigated in a few interesting studies that are reviewed here and extended using our patient cohort.

Methods

Our large cohort of 395 probable AD patients had longitudinal information on the BPSD (Neuropsychiatric Inventory), which was used to dichotomise patients into whether they had ever suffered from a given symptom within the study period, or not. These measures were related to the DRD1 (A‐48G), DRD2 (ser311cys; C‐ins/del), DRD3 (ser9gly) and DRD4 (VNTR) genotype and allele frequencies.

Results

Associations were revealed between DRD3 and elation, and between DRD4 with agitation/aggression and with depression; however, these findings do not remain significant after correction for multiple testing. No associations were found with the other genetic variants and these symptoms and no associations were observed between any of the polymorphic variants examined and delusions, hallucinations, psychosis and aberrant motor behaviour.

Conclusion

Our data, in combination with a review of the literature, reveal a potential role for the VNTR variant of DRD4 in the development of depression in AD patients. The findings presented here need to be replicated in large, well characterised longitudinal cohorts. Copyright © 2009 John Wiley & Sons, Ltd.
Functionally linked resting‐state networks reflect the underlying structural connectivity architecture of the human brain
Authors: van den Heuvel Martijn P. , Mandl René C.W. , Kahn René S. , Hulshoff Pol Hilleke E.
Published: February 2009

During rest, multiple cortical brain regions are functionally linked forming resting‐state networks. This high level of functional connectivity within resting‐state networks suggests the existence of direct neuroanatomical connections between these functionally linked brain regions to facilitate the ongoing interregional neuronal communication. White matter tracts are the structural highways of our brain, enabling information to travel quickly from one brain region to another region. In this study, we examined both the functional and structural connections of the human brain in a group of 26 healthy subjects, combining 3 Tesla resting‐state functional magnetic resonance imaging time‐series with diffusion tensor imaging scans. Nine consistently found functionally linked resting‐state networks were retrieved from the resting‐state data. The diffusion tensor imaging scans were used to reconstruct the white matter pathways between the functionally linked brain areas of these resting‐state networks. Our results show that well‐known anatomical white matter tracts interconnect at least eight of the nine commonly found resting‐state networks, including the default mode network, the core network, primary motor and visual network, and two lateralized parietal‐frontal networks. Our results suggest that the functionally linked resting‐state networks reflect the underlying structural connectivity architecture of the human brain. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc.
Empathic neural responses to others' pain are modulated by emotional contexts
Authors: Han Shihui , Fan Yan , Xu Xiaojing , Qin Jungang , Wu Bing , Wang Xiaoying , Aglioti Salvatore M. , Mao Lihua
Published: February 2009

Recent brain imaging studies indicate that empathy for pain relies upon both the affective and/or the sensorimotor nodes of the pain matrix, and empathic neural responses are modulated by stimulus reality, personal experience, and affective link with others. The current work investigated whether and how empathic neural responses are modulated by emotional contexts in which painful stimulations are perceived. Using functional magnetic resonance imaging (fMRI), we first showed that perceiving a painful stimulation (needle penetration) applied to a face with neutral expression induced activation in the anterior cingulate cortex (ACC) relative to nonpainful stimulation (Q‐tip touch). However, when observation of the painful stimuli delivered to a neutral face was intermixed with observation of painful or happy faces, the ACC activity decreased while the activity in the face area of the secondary somatosensory cortex increased to the painful stimulation. Moreover, the secondary somatosensory activity associated with the painful stimulation decreased when the painful stimulation was applied to faces with happy and painful expressions. The findings suggest that observing painful stimuli in an emotional context weakens affective responses but increases sensory responses to perceived pain and implies possible interactions between the affective and sensory components of the pain matrix during empathy for pain. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc.
Source connectivity analysis with MEG and EEG
Authors: Schoffelen Jan‐Mathijs , Gross Joachim
Published: February 2009

Interactions between functionally specialized brain regions are crucial for normal brain function. Magnetoencephalography (MEG) and electroencephalography (EEG) are techniques suited to capture these interactions, because they provide whole head measurements of brain activity in the millisecond range. More than one sensor picks up the activity of an underlying source. This field spread severely limits the utility of connectivity measures computed directly between sensor recordings. Consequentially, neuronal interactions should be studied on the level of the reconstructed sources. This article reviews several methods that have been applied to investigate interactions between brain regions in source space. We will mainly focus on the different measures used to quantify connectivity, and on the different strategies adopted to identify regions of interest. Despite various successful accounts of MEG and EEG source connectivity, caution with respect to the interpretation of the results is still warranted. This is due to the fact that effects of field spread can never be completely abolished in source space. However, in this very exciting and developing field of research this cautionary note should not discourage researchers from further investigation into the connectivity between neuronal sources. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc.
Mutational analysis of IDH1 codon 132 in glioblastomas and other common cancers
Authors: Kang Mi Ran , Kim Min Sung , Oh Ji Eun , Kim Yoo Ri , Song Sang Yong , Seo Seong Il , Lee Ji Youl , Yoo Nam Jin , Lee Sug Hyung
Published: February 2009

Missense somatic mutations in IDH1 gene affecting codon 132 have recently been reported in glioblastoma multiforme (GBM) and other gliomas. The recurrent nature of the IDH1 mutations in the same amino acid strongly suggests that the mutations may play important roles in the pathogenesis of glial tumors. The aim of this study was to see whether the IDH1 codon 132 mutations occur in other human cancers besides glial tumors. We also attempted to confirm the occurrence of the IDH1 mutations in GBM of Korean patients. We have analyzed 1,186 cancer tissues from various origins, including carcinomas from breast, colon, lung, stomach, esophagus, liver, prostate, urinary bladder, ovary, uterine cervix, skin and kidney, and malignant mesotheliomas, primary GBM, malignant meningiomas, multiple myelomas and acute leukemias by single‐strand conformation polymorphism analysis. We found four IDH1 codon 132 mutations in the GBM (4/25; 16.0%), two in the prostate carcinomas (2/75; 2.7%) and one in the B‐acute lymphoblastic leukemias (B‐ALL) (1/60; 1.7%), but none in other cancers. The IDH1 mutations consisted of five p.R132H and two p.R132C mutations. The data indicate that IDH1 codon 132 mutations occur not only in GBM, but also in prostate cancers and B‐ALL. This study suggests that despite the infrequent incidence of the IDH1 mutations in prostate cancers and B‐ALL, mutated IDH1 could be therapeutically targeted in these cancers and in glial tumors with the IDH1 mutations. © 2009 UICC
Combined targeting of interleukin‐6 and vascular endothelial growth factor potently inhibits glioma growth and invasiveness
Authors: Saidi Ahlame , Hagedorn Martin , Allain Nathalie , Verpelli Chiara , Sala Carlo , Bello Lorenzo , Bikfalvi Andreas , Javerzat Sophie
Published: February 2009

Interleukin‐6 (IL6) and vascular endothelial growth factor (VEGFA) are abundantly produced by glioma cells and contribute to malignancy by promoting angiogenesis, cell proliferation and resistance to apoptosis. We compared the effect of inhibiting IL6 and VEGF on U87‐derived experimental glioma grown on the chick chorio‐allantoic membrane (CAM) or in the brain of xenografted mice. Tumor growth was monitored by biomicroscopy and immunohistology. In vitro, IL6 knockdown had no effect on proliferation but substantially enhanced invasion. In the CAM experimental glioma, IL6 or VEGF knockdown reduced growth and vascularization of the tumors with a comparable efficiency, but increased invasion of residual tumor cells. In contrast, combined IL6/VEGF knockdown not only showed enhanced reduction of tumor growth and angiogenesis but also significantly prevented invasion of residual tumor cells. In mice, combining IL6 knockdown and Avastin™ treatment completely abrogated tumor development and infiltration. Molecular response of tumor cells to single or combined treatment was studied by transcriptomic profiling. Many cell cycle promoting genes and chromatin components were silenced in the double knockdown. In addition, specific migratory signatures detected in tumors under single IL6 or VEGF knockdown were partially erased in combined IL6/VEGF knockdown tumors. Our results show that treatment with a combination of IL6 and VEGF inhibitors brings synergistic antitumoral benefit and reduces global activity of major pathways of cell survival, proliferation and invasiveness in remaining tumor cells that may be induced by using VEGF or IL6 inhibitors alone. © 2009 UICC
Systemic delivery of siRNA specific to tumor mediated by atelocollagen: Combined therapy using siRNA targeting Bcl‐xL and cisplatin against prostate cancer
Authors: Mu Ping , Nagahara Shunji , Makita Naoki , Tarumi Yuzo , Kadomatsu Kenji , Takei Yoshifumi
Published: February 2009

The largest obstacle to the effective use of short interfering RNA (siRNA) in an animal body is the ability to deliver it to the target tissue. Here we showed a systemic delivery method of siRNA specific to pregrown solid tumors via atelocollagen. Atelocollagen facilitated the selective uptake of siRNA into the tumors when an siRNA/atelocollagen complex was administered intravenously to mice. We chose a Bcl‐xL protein as a model target to prove the therapeutic efficacy of the atelocollagen‐mediated method. Bcl‐xL acts as an anti‐apoptotic factor, which is overexpressed in many cancers, including prostate cancer. One of the four designed siRNAs to human Bcl‐xL potently inhibited the expression of Bcl‐xL by the PC‐3 human prostate cancer cell line in vitro, leading to cell apoptosis. Intravenous injections for3 consecutive days (siRNA, 100 μg/injection per day as a complex with atelocollagen) effectively downregulated Bcl‐xL expression in the PC‐3 xenograft. We administered four series of 3 consecutive days of intravenous injections each, for a total of 12 injections, which significantly inhibited tumor growth when the treatment was combined with cisplatin (2 mg/kg). Local injection of Bcl‐xL siRNA also potently inhibited tumor growth. All of the tumors treated with Bcl‐xL siRNA/atelocollagen complex via both intravenous and intratumoral injection showed terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling‐positive apoptosis. There were no severe side effects such as interferon‐α induction and liver or renal damage in mice. Our results indicate that systemic delivery of siRNA via atelocollagen, which specifically targets tumors, is safe and feasible for cancer therapy. © 2009 UICC
Family history of hormonal cancers and colorectal cancer risk: A case‐control study conducted in Ontario
Authors: Jang Ji‐Hyun , Cotterchio Michelle , Gallinger Steven , Knight Julia A. , Daftary Darshana
Published: February 2009

Aggregation of cancers among families with highly penetrant genetic mutations such as hereditary nonpolyposis colorectal cancer is well‐described. However, there is a paucity of data regarding familial aggregation of hormonal cancers (cancers of the breast, endometrial, ovarian and prostate) and colorectal cancer (CRC) in the general population. We investigated the association between having a first‐degree family history of breast, endometrial, ovarian, or prostate cancer and CRC risk. Population‐based CRC cases and controls were recruited by the Ontario Familial Colorectal Cancer Registry (OFCCR). Logistic regression was conducted to obtain odds ratio (OR) estimates and 95% confidence intervals (95% CIs). First‐degree family history of breast cancer was associated with a modest, borderline statistically significant increased CRC risk (age‐, sex‐adjusted OR = 1.2, 95% CI = 1.0, 1.5). The magnitude of CRC risk was greatest if more than one first‐degree kin had breast cancer (age‐, sex‐adjusted OR = 1.7, 95% CI = 1.0, 2.0), as well as if the kin was diagnosed at >50 years of age (age‐, sex‐adjusted OR = 1.4, 95% CI = 1.1, 1.8). Family history of ovarian cancer was associated with reduced CRC risk (multivariate‐adjusted OR = 0.6, 95% CI = 0.3, 1.0). Although statistically significant increases in CRC risk were observed in the age‐, sex‐adjusted OR estimates for family history of endometrial and prostate cancers, the associations were no longer significant after multivariate‐adjustment. In conclusion, individuals with a first‐degree kin with breast cancer may have a modest increased risk for CRC compared to individuals without. © 2009 UICC
Enhanced invasiveness of drug‐resistant acute myeloid leukemia cells through increased expression of matrix metalloproteinase‐2
Authors: Song Ju Han , Kim Seung Hyun , Cho Daeho , Lee Il‐Kwon , Kim Hyeoung‐Joon , Kim Tae Sung
Published: February 2009

The acquired drug resistance as well as extramedullary tissue infiltration of leukemic cells is a major obstacle in leukemia treatment. Excessive egress of leukemia cell blasts results in invasion into various organs or tissues, which is facilitated by the catalytic activities of matrix metalloproteinases (MMPs). However, the migration of chemoresistant leukemia cells remains unclear. Here, we generated drug‐resistant variants of the human acute myeloid leukemia cell line (AML‐2/WT) by stepwise exposure to anticancer drugs and evaluated the level of MMP‐2 in the drug‐resistant variants, along with their invasiveness. Each of the drug‐resistant cell variants demonstrated predominant increases in the expression and gelatinolytic activity of MMP‐2 as well as in invasiveness, which were significantly suppressed by both a MMP‐2 inhibitor and a blocking antibody. Knockdown experiments using MMP‐2 short hairpin RNA also indicated that its upregulation was strongly associated with the cells' increased invasive properties. Importantly, elevated levels of MMP‐2 activity and invasiveness were observed in ex vivo mononuclear cell of bone marrow from patients with poor responses to chemotherapy. These findings suggest that advanced malignancy due to acquired drug resistance is responsible for the progressive invasiveness of leukemia cells via MMP‐2. © 2009 UICC
Meat and fat intake and pancreatic cancer risk in the Netherlands Cohort Study
Authors: Heinen Mirjam M. , Verhage Bas A.J. , Goldbohm R. Alexandra , van den Brandt Piet A.
Published: February 2009

Meat contains numerous carcinogens, such as heterocyclic amines, polycyclic aromatic hydrocarbons, and N‐nitroso compounds, which can be derived either from natural food or during the process of food preparation. These carcinogens may increase pancreatic cancer risk. Furthermore, studies in animals showed that polyunsaturated fatty acids, especially linoleic acid, increase pancreatic cancer risk. We examined prospectively the relation between pancreatic cancer risk and intake of fresh meat, processed meat, fish, eggs, total fat, and different types of fat. The Netherlands Cohort Study consisted of 120,852 men and women who completed a baseline questionnaire in 1986. After 13.3 years of follow‐up, 350 pancreatic cancer cases (66% microscopically confirmed) were available for analysis. A validated 150‐item food‐frequency questionnaire was used to calculate intake of fresh meat, processed meat, fish, eggs, fat and different types of fat. No association was found when examining the association between intake of fresh meat, other types of meat, fish, eggs, dietary intake of total fat and different types of fat and risk of pancreatic cancer. It is important for future studies to investigate the relation between different meat‐cooking methods and pancreatic cancer. © 2009 UICC
Induction of osteopontin expression by nicotine and cigarette smoke in the pancreas and pancreatic ductal adenocarcinoma cells
Authors: Chipitsyna Galina , Gong Qiaoke , Anandanadesan Rathai , Alnajar Amer , Batra Surinder K. , Wittel Uwe A. , Cullen Diane M. , Akhter Mohammed P. , Denhardt David T. , Yeo Charles J. , Arafat Hwyda A.
Published: February 2009

Pancreatic ductal adenocarcinoma (PDA) is a lethal disease with etiological association with cigarette smoking. Nicotine, an important component of cigarettes, exists at high concentrations in the bloodstream of smokers. Osteopontin (OPN) is a secreted phosphoprotein that confers on cancer cells a migratory phenotype and activates signaling pathways that induce cell survival, proliferation, invasion, and metastasis. Here, we investigated the potential molecular basis of nicotine's role in PDA through studying its effect on OPN. Nicotine significantly (p < 0.02) increased OPN mRNA and protein secretion in PDA cells through activation of the OPN gene promoter. The OPN mRNA induction was inhibited by the nicotinic acetylcholine receptor antagonist, mechamylamine. Further, the tyrosine kinase inhibitor genistein inhibited the nicotine‐mediated induction of OPN, suggesting that mitogen activated protein kinase signaling mechanism is involved. Nicotine activated the phosphorylation of ERK1/2, but not p38 or c‐Jun NH2‐terminal MAP kinases. Inhibition of ERK1/2 activation reduced the nicotine‐induced OPN synthesis. Rats exposed to cigarette smoke showed a dose‐dependent increase in pancreatic OPN that paralleled the rise of pancreatic and plasma nicotine levels. Analysis of cancer tissue from invasive PDA patients, the majority of whom were smokers, showed the presence of significant amounts of OPN in the malignant ducts and the surrounding pancreatic acini. Our data suggest that nicotine may contribute to PDA pathogenesis through upregulation of OPN. They provide the first insight into a nicotine‐initiated signal transduction pathway that regulates OPN as a possible tumorigenic mechanism in PDA. © 2009 UICC
Functional coexpression of Interleukin (IL)‐7 and its receptor (IL‐7R) on Hodgkin and Reed‐Sternberg cells: Involvement of IL‐7 in tumor cell growth and microenvironmental interactions of Hodgkin's lymphoma
Authors: Cattaruzza Lara , Gloghini Annunziata , Olivo Karin , Di Francia Raffaele , Lorenzon Debora , De Filippi Rosaria , Carbone Antonino , Colombatti Alfonso , Pinto Antonio , Aldinucci Donatella
Published: February 2009

The clinical and pathological features of classical Hodgkin lymphoma (cHL) mirror an abnormal tissue and systemic immune response due to the production of a variety of cytokines and chemokines by the malignant Hodgkin‐Reed‐Sternberg (H‐RS) cells and/or surrounding reactive cells. Here, we demonstrate that HL‐derived cell lines (L‐428, KM‐H2, HDLM‐2, L‐1236 and L‐540) and primary H‐RS cells from lymph node tissues of HL patients express the IL‐7(R) receptor. IL‐7 appears to be involved in autocrine circuitries of HL because L‐1236, HDLM‐2 and KM‐H2 cells display the constitutive production of IL‐7 and neutralizing anti‐IL‐7 antibodies induces a statistically significant inhibition of their basal proliferation. In addition, IL‐7, either exogenous or fibroblasts‐derived, promotes the clonogenic growth and reduces apoptosis of cultured H‐RS cells, being also able to partially protect these cells from the cytotoxic effects of doxorubicin. We also provide evidence that IL‐7 stimulates IL‐6 secretion from IL‐7R‐expressing fibroblasts from HL‐involved lymph nodes (HLFs), and that a striking increase in IL‐6 secretion can be observed in cocultures of HLFs with L1236 cells. Finally, we show that L‐1236 cells‐derived IL‐7 represents a costimulator for proliferation of purified CD4+CD25+CD127dim/− regulatory T cells (Tregs). Taken together, our data indicates that the IL‐7/IL‐7R axis constitutes an additional signaling pathway between H‐RS cells and their reactive cellular background, thereby affecting proliferation and survival of tumor cells, acting as a cofactor for Tregs expansion and enhancing the microenviromental production of IL‐6, a cytokine associated with the presence of “B” symptoms and a poor outcome in HL patients. © 2009 UICC
Identification of novel microRNA targets based on microRNA signatures in bladder cancer
Authors: Ichimi Takahiro , Enokida Hideki , Okuno Yasushi , Kunimoto Ryo , Chiyomaru Takeshi , Kawamoto Ken , Kawahara Kazuya , Toki Kazuki , Kawakami Kazumori , Nishiyama Kenryu , Tsujimoto Gozoh , Nakagawa Masayuki , Seki Naohiko
Published: February 2009

MicroRNAs (miRNAs) are small noncoding RNAs that negatively regulate protein‐coding genes. To identify miRNAs that have a tumor suppressive function in bladder cancer (BC), 156 miRNAs were screened in 14 BCs, 5 normal bladder epithelium (NBE) samples and 3 BC cell lines. We identified a subset of 7 miRNAs (miR‐145, miR‐30a‐3p, miR‐133a, miR‐133b, miR‐195, miR‐125b and miR‐199a*) that were significantly downregulated in BCs. To confirm these results, 104 BCs and 31 NBEs were subjected to real‐time RT‐PCR‐based experiments, and the expression levels of each miRNA were significantly downregulated in BCs (p < 0.0001 in all). Receiver‐operating characteristic curve analysis revealed that the expression levels of these miRNAs had good sensitivity (>70%) and specificity (>75%) to distinguish BC from NBE. Our target search algorithm and gene‐expression profiling in BCs (Kawakami et al., Oncol Rep 2006;16:521–31) revealed that Keratin7 (KRT7) mRNA was a common target of the downregulated miRNAs, and the mRNA expression levels of KRT7 were significantly higher in BCs than in NBEs (p = 0.0004). Spearman rank correlation analysis revealed significant inverse correlations between KRT7 mRNA expression and each downregulated miRNA (p < 0.0001 in all). Gain‐of‐function analysis revealed that KRT7 mRNA was significantly reduced by transfection of 3 miRNAs (miR‐30‐3p, miR‐133a and miR‐199a*) in the BC cell line (KK47). In addition, significant decreases in cell growth were observed after transfection of 3 miRNAs and si‐KRT7 in KK47, suggesting that miR‐30‐3p, miR‐133a and miR‐199a* may have a tumor suppressive function through the mechanism underlying transcriptional repression of KRT7. © 2009 UICC
Identification of integrins α6 and β7 as c‐Jun‐ and transformation‐relevant genes in highly invasive fibrosarcoma cells
Authors: Kielosto Mari , Nummela Pirjo , Järvinen Kristiina , Yin Miao , Hölttä Erkki
Published: February 2009

Understanding the mechanisms of tumor cell invasion is essential for our attempts to prevent cancer deaths. We screened by DNAmicroarrays the c‐Jun‐ and transformation‐related gene expression changes inS‐adenosylmethionine decarboxylase (AdoMetDC)‐overexpressing mouse fibroblasts that are highly invasivein vivo, and their derivatives expressing a tetracycline‐inducible dominant‐negative mutant of c‐Jun (TAM67) or c‐Jun shRNA. Among the small set of target genes detected were integrins α6 and β7, cathepsin L and thymosin β4, all upregulated in the AdoMetDC‐transformed cells and downregulated upon reversal of transformation by TAM67 or c‐Jun shRNA. The upregulation of integrin α6 subunit, pairing with integrin β1, endowed the transformed cells with the capability to attach to basement membrane laminin and to spread. Further, inhibition of integrin α6 or β1 function with neutralizing antibodies blocked the invasiveness of AdoMetDC‐transformants and human HT‐1080 fibrosarcoma cells in three‐dimensional Matrigel. Moreover, immunohistochemical analyses showed strong integrin α6 staining in high‐grade human fibrosarcomas. Our data show that c‐Jun can regulate all three key steps of invasion: cell adhesion (integrin α6), basement membrane/extracellular matrix degradation (cathepsin L) and cell migration (thymosin β4). In addition, this is the first study to associate integrin β7, known as a leukocyte‐specific integrin binding to endothelial/epithelial cell adhesion molecules, with the transformed phenotype in cells of nonleukocyte origin. As tumor cell invasion is a prerequisite for metastasis, the observed critical role of integrin α6β1 in fibrosarcoma cell invasion/spreading allures testing antagonists to integrin α6β1, alone or combined with inhibitors of cathepsin L and thymosin β4, as chemotherapeutic agents. © 2009 UICC
Gene expression profiling of alpha‐radiation‐induced rat osteosarcomas: Identification of dysregulated genes involved in radiation‐induced tumorigenesis of bone
Authors: Daino Kazuhiro , Ugolin Nicolas , Altmeyer‐Morel Sandrine , Guilly Marie‐Noëlle , Chevillard Sylvie
Published: February 2009

To better understand the molecular basis of radiation‐induced osteosarcoma (OS), we performed global gene expression profiling of rat OS tumors induced by the bone‐seeking alpha emitter 238Pu, and the expression profiles were compared with those of normal osteoblasts (OB). The expressions of 72 genes were significantly differentially expressed in the tumors related to OB. These included genes involved in the cell adhesion (e.g., Podxl, Col18a1, Cd93, Emcn and Vcl), differentiation, developmental processes (e.g., Hhex, Gata2, P2ry6, P2rx5, Cited2, Osmr and Igsf10), tumor‐suppressor function (e.g., Nme3, Blcap and Rrm1), Src tyrosine kinase signaling (e.g., Hck, Shf, Arhgap29, Cttn and Akap12), and Wnt/β‐catenin signaling (e.g., Fzd6, Lzic, Dkk3 and Ctnna1) pathways. Expression changes of several genes were validated by quantitative real‐time RT‐PCR analysis. Notably, all of the identified genes involved in the Wnt/β‐catenin signaling pathway were known or proposed to be negative regulators of this pathway and were downregulated in the tumors, suggesting the activation of β‐catenin in radiation‐induced OS. By using immunohistochemical and immunoblot analyses, constitutive activation of the Wnt/β‐catenin signaling pathway in the tumors was confirmed by observing nuclear and/or cytoplasmic localization of β‐catenin and a decrease in its inactive (phosphorylated) form. Furthermore, we found a significant reduction in the levels of glycogen synthase kinase 3β (GSK‐3β) protein in the tumors relative to OB. Taken together, these findings provide new insights into the molecular basis of radiation‐induced OS. © 2009 UICC
Methylation of multiple genes as molecular markers for diagnosis of a small, well‐differentiated hepatocellular carcinoma
Authors: Moribe Toyoki , Iizuka Norio , Miura Toshiaki , Kimura Naoki , Tamatsukuri Shigeru , Ishitsuka Hideo , Hamamoto Yoshihiko , Sakamoto Kazuhiko , Tamesa Takao , Oka Masaaki
Published: February 2009

The current study was conducted to identify robust methylation markers and their combinations that may prove useful for the diagnosis of early hepatocellular carcinoma (HCC). To achieve this, we performed in silico CpG mapping, direct sequencing and pyrosequencing after bisulfite treatment, and quantitative methylation‐specific PCR (MSP) in HCC and non‐HCC liver tissues. In the filtering group (25 HCCs), our direct sequencing analysis showed that, among the 12 methylation genes listed by in silico CpG mapping, 7 genes (RASSF1A, CCND2, SPINT2, RUNX3, GSTP1, APC and CFTR) were aberrantly methylated in stages I and II HCCs. In the validation group (20 pairs of HCCs and the corresponding non‐tumor liver tissues), pyrosequencing analysis confirmed that the 7 genes were aberrantly and strongly methylated in early HCCs, but not in any of the corresponding non‐ tumor liver tissues (p < 0.00001). The results obtained using our novel quantitative MSP assay correlated well with those observed using the pyrosequencing analysis. Notably, in MSP assay, RASSF1A showed the most robust performance for the discrimination of HCC and non‐HCC liver tissues. Furthermore, a combination of RASSF1A, CCND2 and SPINT2 showed 89–95% sensitivity, 91–100% specificity and 89–97% accuracy in discriminating between HCC and non‐HCC tissues, and correctly diagnosed all early HCCs. These results indicate that the combination of these 3 genes may aid in the accurate diagnosis of early HCC. © 2009 UICC
On 2‐factorizations of the complete graph: From the k‐pyramidal to the universal property
Authors: Bonvicini Simona , Mazzuoccolo Giuseppe , Rinaldi Gloria
Published: February 2009

We consider 2‐factorizations of complete graphs that possess an automorphism group fixing k⩾0 vertices and acting sharply transitively on the others. We study the structures of such factorizations and consider the cases in which the group is either abelian or dihedral in some more details. Combining results of the first part of the paper with a result of D. Bryant, J Combin Des, 12 (2004), 147–155, we prove that the class of 2‐factorizations of complete graphs is universal. Namely each finite group is the full automorphism group of a 2‐factorization of the class. © 2009 Wiley Periodicals, Inc. J Combin Designs 17: 211‐228, 2009