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1.
MethodsX ; 10: 102075, 2023.
Article in English | MEDLINE | ID: mdl-36875342

ABSTRACT

It is often logistically impractical to measure forest defoliation events in the field due to seasonal variability in larval feeding phenology (e.g., start, peak, and end) in any given year. As such, field data collections are either incomplete or at coarse temporal resolutions, both of which result in inaccurate estimation of annual defoliation (frass or foliage loss). Using Choristoneura pinus F. and Lymantria dispar dispar L., we present a novel approach that leverages a weather-driven insect simulation model (BioSIM) and defoliation field data. Our approach includes optimization of a weighting parameter (w) for each instar and imputation of defoliation. Results show a negative skew in this weighting parameter, where the second to last instar in a season exhibits the maximum consumption and provides better estimates of annual frass and foliage biomass loss where sampling data gaps exist. Respective cross-validation RMSE (and normalized RMSE) results for C. pinus and L. dispar dispar are 77.53 kg·ha-1 (0.16) and 38.24 kg·ha-1 (0.02) for frass and 74.85 kg·ha-1 (0.10) and 47.77 kg·ha-1 (0.02) for foliage biomass loss imputation. Our method provides better estimates for ecosystem studies that leverage remote sensing data to scale defoliation rates from the field to broader landscapes and regions.•Utilize fine temporal resolution insect life cycle data derived from weather-driven insect simulation model (BioSIM) to bridge critical gaps in coarse temporal resolution defoliation field data.•Fitting distributions to optimize the instar weighting parameter (w) and impute frass and foliage biomass loss based on a cumulative density function (CDF).•Enables accurate estimation of annual defoliation impacts on ecosystems across multiple insect taxa that exhibit distinct but seasonally variable feeding phenology.

2.
J Geophys Res Biogeosci ; 127(8): e2022JG006876, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36248721

ABSTRACT

High-resolution space-based spectral imaging of the Earth's surface delivers critical information for monitoring changes in the Earth system as well as resource management and utilization. Orbiting spectrometers are built according to multiple design parameters, including ground sampling distance (GSD), spectral resolution, temporal resolution, and signal-to-noise ratio. Different applications drive divergent instrument designs, so optimization for wide-reaching missions is complex. The Surface Biology and Geology component of NASA's Earth System Observatory addresses science questions and meets applications needs across diverse fields, including terrestrial and aquatic ecosystems, natural disasters, and the cryosphere. The algorithms required to generate the geophysical variables from the observed spectral imagery each have their own inherent dependencies and sensitivities, and weighting these objectively is challenging. Here, we introduce intrinsic dimensionality (ID), a measure of information content, as an applications-agnostic, data-driven metric to quantify performance sensitivity to various design parameters. ID is computed through the analysis of the eigenvalues of the image covariance matrix, and can be thought of as the number of significant principal components. This metric is extremely powerful for quantifying the information content in high-dimensional data, such as spectrally resolved radiances and their changes over space and time. We find that the ID decreases for coarser GSD, decreased spectral resolution and range, less frequent acquisitions, and lower signal-to-noise levels. This decrease in information content has implications for all derived products. ID is simple to compute, providing a single quantitative standard to evaluate combinations of design parameters, irrespective of higher-level algorithms, products, applications, or disciplines.

3.
Plant Dis ; 102(11): 2233-2240, 2018 11.
Article in English | MEDLINE | ID: mdl-30145947

ABSTRACT

Spectral phenotyping is an efficient method for the nondestructive characterization of plant biochemical and physiological status. We examined the ability of a full range (350 to 2,500 nm) of foliar spectral data to (i) detect Potato virus Y (PVY) and physiological effects of the disease in visually asymptomatic leaves, (ii) classify different strains of PVY, and (iii) identify specific potato cultivars. Across cultivars, foliar spectral profiles of PVY-infected leaves were statistically different (F = 96.1, P ≤ 0.001) from noninfected leaves. Partial least-squares discriminate analysis (PLS-DA) accurately classified leaves as PVY infected (validation κ = 0.73) and the shortwave infrared spectral regions displayed the strongest correlations with infection status. Although spectral profiles of different PVY strains were statistically different (F = 6.4, P ≤ 0.001), PLS-DA did not classify different strains well (validation κ = 0.12). Spectroscopic retrievals revealed that PVY infection decreased photosynthetic capacity and increased leaf lignin content. Spectral profiles of potato cultivars also differed (F = 9.2, P ≤ 0.001); whereas average spectral classification was high (validation κ = 0.76), the accuracy of classification varied among cultivars. Our study expands the current knowledge base by (i) identifying disease presence before the onset of visual symptoms, (ii) providing specific biochemical and physiological responses to disease infection, and (iii) discriminating between multiple cultivars within a single plant species.


Subject(s)
Plant Diseases/prevention & control , Solanum tuberosum/virology , Spectrum Analysis/methods , Plant Diseases/virology , Plant Leaves/physiology , Plant Leaves/virology , Potyvirus/classification , Solanum tuberosum/physiology
4.
Luminescence ; 33(4): 654-659, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29498214

ABSTRACT

X-Ray excited luminescence (radioluminescence, RL) spectra from nominally pure crystalline zinc oxide (ZnO) are reported. The temperature range is from 20 to 673 K. Significant changes of emission band energies and intensities are observed across the temperature range. Photon energies of emission bands linked to the band gap decrease with increasing temperature in RL. This dependence fits the theoretical equations describing the temperature response of the ZnO band gap. Defect related luminescence includes a complex mixture of features at low temperature for RL. Thermoluminescence (TL) signals from 20 to 300 K confirm the presence of an unresolved feature in the RL data. Comments on the possible origin of these bands are summarized. The data underline that it is essential to record the temperature dependence for the luminescence data in order to separate overlapping spectral features.


Subject(s)
Luminescence , Temperature , Zinc Oxide/chemistry , Luminescent Measurements
5.
Sci Rep ; 7(1): 5147, 2017 07 11.
Article in English | MEDLINE | ID: mdl-28698554

ABSTRACT

Osteoarthritis (OA) is characterised by progressive destruction of articular cartilage and chondrocyte cell death. Here, we show the expression of the endogenous peptide urocortin1 (Ucn1) and two receptor subtypes, CRF-R1 and CRF-R2, in primary human articular chondrocytes (AC) and demonstrate its role as an autocrine/paracrine pro-survival factor. This effect could only be removed using the CRF-R1 selective antagonist CP-154526, suggesting Ucn1 acts through CRF-R1 when promoting chondrocyte survival. This cell death was characterised by an increase in p53 expression, and cleavage of caspase 9 and 3. Antagonism of CRF-R1 with CP-154526 caused an accumulation of intracellular calcium (Ca2+) over time and cell death. These effects could be prevented with the non-selective cation channel blocker Gadolinium (Gd3+). Therefore, opening of a non-selective cation channel causes cell death and Ucn1 maintains this channel in a closed conformation. This channel was identified to be the mechanosensitive channel Piezo1. We go on to determine that this channel inhibition by Ucn1 is mediated initially by an increase in cyclic adenosine monophosphate (cAMP) and a subsequent inactivation of phospholipase A2 (PLA2), whose metabolites are known to modulate ion channels. Knowledge of these novel pathways may present opportunities for interventions that could abrogate the progression of OA.


Subject(s)
Cartilage, Articular/cytology , Ion Channels/chemistry , Ion Channels/metabolism , Receptors, Corticotropin-Releasing Hormone/metabolism , Urocortins/genetics , Autocrine Communication , Calcium/metabolism , Cartilage, Articular/metabolism , Cell Survival/drug effects , Cells, Cultured , Chondrocytes/cytology , Chondrocytes/metabolism , Cyclic AMP/metabolism , Humans , Paracrine Communication , Peptide Fragments/pharmacology , Peptides, Cyclic/pharmacology , Protein Conformation , Pyrimidines/pharmacology , Pyrroles/pharmacology , Signal Transduction , Urocortins/metabolism
6.
Br J Cancer ; 115(9): 1078-1086, 2016 Oct 25.
Article in English | MEDLINE | ID: mdl-27685442

ABSTRACT

BACKGROUND: Prostate cancer (PCa) is the most common male cancer in the United Kingdom and we aimed to identify clinically relevant biomarkers corresponding to stage progression of the disease. METHODS: We used enhanced proteomic profiling of PCa progression using iTRAQ 3D LC mass spectrometry on high-quality serum samples to identify biomarkers of PCa. RESULTS: We identified >1000 proteins. Following specific inclusion/exclusion criteria we targeted seven proteins of which two were validated by ELISA and six potentially interacted forming an 'interactome' with only a single protein linking each marker. This network also includes accepted cancer markers, such as TNF, STAT3, NF-κB and IL6. CONCLUSIONS: Our linked and interrelated biomarker network highlights the potential utility of six of our seven markers as a panel for diagnosing PCa and, critically, in determining the stage of the disease. Our validation analysis of the MS-identified proteins found that SAA alongside KLK3 may improve categorisation of PCa than by KLK3 alone, and that TSR1, although not significant in this model, might also be a clinically relevant biomarker.


Subject(s)
Biomarkers, Tumor/metabolism , Prostatic Neoplasms/blood , Prostatic Neoplasms/pathology , Proteomics/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Biomarkers, Tumor/blood , Blood Chemical Analysis/methods , Chromatography, Liquid , Disease Progression , Enzyme-Linked Immunosorbent Assay , Humans , Male , Pilot Projects , Prognosis , Prostatic Neoplasms/diagnosis , Reproducibility of Results
8.
Phys Life Rev ; 18: 1-21, 2016 09.
Article in English | MEDLINE | ID: mdl-27291090

ABSTRACT

This paper proposes an essay concerning the understanding of human behaviours and crisis management of crowds in extreme situations, such as evacuation through complex venues. The first part focuses on the understanding of the main features of the crowd viewed as a living, hence complex system. The main concepts are subsequently addressed, in the second part, to a critical analysis of mathematical models suitable to capture them, as far as it is possible. Then, the third part focuses on the use, toward safety problems, of a model derived by the methods of the mathematical kinetic theory and theoretical tools of evolutionary game theory. It is shown how this model can depict critical situations and how these can be managed with the aim of minimizing the risk of catastrophic events.


Subject(s)
Behavior , Crowding , Informatics/methods , Models, Theoretical , Game Theory , Humans , Stress, Psychological
9.
Int J Biochem Cell Biol ; 60: 130-8, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25541373

ABSTRACT

Urocortin (Ucn 1), a 40 amino acid long peptide related to corticotropin releasing factor (CRF) was discovered 19 years ago, based on its sequence homology to the parent molecule. Its existence was inferred in the CNS because of anatomical and pharmacological discrepancies between CRF and its two receptor subtypes. Although originally found in the brain, where it has opposing actions to CRF and therefore confers stress-coping mechanisms, Ucn 1 has subsequently been found throughout the periphery including heart, lung, skin, and immune cells. It is now well established that this small peptide is involved in a multitude of physiological and pathophysiological processes, due to its receptor subtype distribution and promiscuity in second messenger signalling pathways. As a result of extensive studies in this field, there are now well over one thousand peer reviewed publications involving Ucn 1. In this review, we intend to highlight some of the less well known actions of Ucn 1 and in particular its role in neuronal cell protection and maintenance of the skeletal system, both by conventional methods of reviewing the literature and using bioinformatics, to highlight further associations between Ucn 1 and disease conditions. Understanding how Ucn 1 works in these tissues, will help to unravel its role in normal and pathophysiological processes. This would ultimately allow the generation of putative medical interventions for the alleviation of important diseases such as Parkinson's disease, arthritis, and osteoporosis.


Subject(s)
Parkinson Disease/metabolism , Urocortins/metabolism , Animals , Arthritis/genetics , Arthritis/metabolism , Humans , Osteoporosis/genetics , Osteoporosis/metabolism , Parkinson Disease/genetics , Urocortins/genetics
10.
Radiat Prot Dosimetry ; 158(4): 373-7, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24101655

ABSTRACT

Numerous materials have been proposed for thermoluminescence dosemeter, and the example of highest sensitivity is cited as magnesium orthosilicate doped with terbium (Mg2SiO4:Tb). Nevertheless, the material is currently not commercially attractive because the sensitivity varies greatly with synthesis techniques. This is a multi-parameter problem, and the current work explores some of the conditions required to consistently enhance the response. These new results show that to get a high TL response, Mg2SiO4:Tb should be prepared at a high temperature of at least 1500°C, for sintering times of several hours. In the current example, the optimum time was 6 h. Signals also vary with the terbium activator concentration, and good responses were achieved with a concentration of Tb at 5 wt %. Overall, this suggests that with careful preparation, the potentially high dosimetry performance might be exploited. The inherent problem of concentration quenching is considered, and the potential benefits of processing the powder with pulse laser annealing are reviewed in the light of successful luminescence and laser studies for rare-earth-doped laser materials.


Subject(s)
Magnesium/chemistry , Silicates/chemistry , Terbium/chemistry , Thermoluminescent Dosimetry/instrumentation , Lasers , Luminescence , Materials Testing , Temperature , Thermoluminescent Dosimetry/methods , X-Ray Diffraction
11.
Cell Death Dis ; 4: e717, 2013 Jul 11.
Article in English | MEDLINE | ID: mdl-23846219

ABSTRACT

Osteoarthritis (OA) is characterized by a loss of joint mobility and pain resulting from progressive destruction and loss of articular cartilage secondary to chondrocyte death and/ or senescence. Certain stimuli including nitric oxide (NO) and the pro-inflammatory cytokine tumor necrosis factor α (TNF-α have been implicated in this chondrocyte death and the subsequent accelerated damage to cartilage. In this study, we demonstrate that a corticotrophin releasing factor (CRF) family peptide, urocortin (Ucn), is produced by a human chondrocyte cell line, C-20/A4, and acts both as an endogenous survival signal and as a cytoprotective agent reducing the induction of apoptosis by NO but not TNF-α when added exogenously. Furthermore, treatment with the NO donor S-nitroso-N-acetyl-D-L-penicillamine upregulates chondrocyte Ucn expression, whereas treatment with TNF-α does not. The chondroprotective effects of Ucn are abolished by both specific ligand depletion (with an anti-Ucn antibody) and by CRF receptor blockade with the pan-CRFR antagonist α-helical CRH(9-41). CRFR expression was confirmed by reverse transcription-PCR with subsequent amplicon sequence analysis and demonstrates that C-20/A4 cells express both CRFR1 and CRFR2, specifically CRFR1α and CRFR2ß. Protein expression of these receptors was confirmed by western blotting. The presence of both Ucn and its receptors in these cells, coupled with the induction of Ucn by NO, suggests the existence of an endogenous autocrine/paracrine chondroprotective mechanism against stimuli inducing chondrocyte apoptosis via the intrinsic/mitochondrial pathway.


Subject(s)
Apoptosis , Chondrocytes/physiology , Nitric Oxide/physiology , Osteoarthritis/drug therapy , Urocortins/metabolism , Base Sequence , Cell Survival , Cells, Cultured , Chondrocytes/drug effects , Cytoprotection , DNA Primers/genetics , Gene Expression , Humans , Nitric Oxide Donors/pharmacology , Receptors, Corticotropin-Releasing Hormone/metabolism , S-Nitroso-N-Acetylpenicillamine/pharmacology , Urocortins/genetics
12.
Luminescence ; 28(3): 253-8, 2013.
Article in English | MEDLINE | ID: mdl-22511618

ABSTRACT

Luminescence data have often been used to study imperfections and to characterize lattice distortions because the signals are sensitive to changes of structure and composition. Previous studies have included intentionally added probe ions such as rare earth ions to sense distortions in local crystal fields caused by modified structural environments. An under-exploited extension of this approach was to use luminescence to monitor crystalline phase changes. A current overview of this new and powerful technique shows that continuous scanning of the sample temperatures immediately offered at least three types of signatures for phase transitions. Because of high sensitivity, luminescence signals were equally responsive to structural changes from inclusions and nanoparticles. These coupled to the host material via long-range interactions and modified the host signals. Two frequently observed examples that are normally overlooked are from nanoparticle inclusions of water and CO2. Examples also indicated that phase transitions were detected in more diverse materials such as superconductors and fullerenes. Finally, luminescence studies have shown that in some crystalline examples, high dose ion implantation of surface layers could induce relaxations and/or structural changes of the entire underlying bulk material. This was an unexpected result and therefore such a possibility has not previously been explored. However, the implications for ion implication are significant and could be far more general than the examples mentioned here.


Subject(s)
Luminescent Measurements/methods , Metals, Rare Earth/chemistry , Crystallization , Luminescence , Molecular Structure , Phase Transition
13.
Oncogene ; 32(38): 4490-9, 2013 Sep 19.
Article in English | MEDLINE | ID: mdl-23108401

ABSTRACT

As colorectal cancer remains the second highest cause of cancer-related deaths in much of the industrialised world, identifying novel strategies to prevent colorectal tumour development remains an important challenge. BAG-1 is a multi-functional protein, the expression of which is up-regulated at relatively early stages in colorectal tumorigenesis. Importantly, BAG-1 is thought to enhance colorectal tumour progression through promoting tumour cell survival. Here, we report for the first time a novel role for BAG-1, establishing it as a suppressor of transforming growth factor ß (TGF-ß1) expression in colorectal tumour cells. Microarray analysis first highlighted the possibility that BAG-1 may regulate TGF-ß1 expression, a key cytokine in normal colonic tissue homoeostasis. Q-RT-PCR and ELISA demonstrated TGFB1 mRNA and protein expression to be significantly increased when BAG1 levels were reduced by small interfering RNA; additionally, induction of BAG-1L caused suppression of TGFB1 mRNA in colorectal tumour cells. Using reporter and chromatin immunoprecipitation assays, a direct association of BAG-1 with the TGFB1 gene regulatory region was identified. Immunohistochemistry and Weiser fraction data indicated that the levels of BAG-1 and TGF-ß1 are inversely correlated in the normal colonic epithelium in vivo, consistent with a role for BAG-1-mediated repression of TGF-ß1 production. In vitro studies showed that the change in TGF-ß1 production following manipulation of BAG-1 is functionally relevant; through induction of anchorage-independent growth in TGF-ß1-dependent normal rat kidney fibroblasts and regulation of SMAD2 phosphorylation in TGF-ß1-sensitive adenoma cells. Taken together, this study identifies the anti-apoptotic protein BAG-1 as a suppressor of the inhibitory growth factor TGF-ß1, suggesting that high expression of BAG-1 can impact on a number of the hallmarks of cancer, of potential importance in promoting the early stages of colorectal tumorigenesis. Establishing BAG-1 as a repressor of TGF-ß1 has important biological implications, and highlights a new role for BAG-1 in colorectal tumorigenesis.


Subject(s)
Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , DNA-Binding Proteins/metabolism , Gene Expression Regulation, Neoplastic , Transcription Factors/metabolism , Transforming Growth Factor beta1/genetics , Carcinoma/genetics , Carcinoma/metabolism , Cell Line, Tumor , Epithelial Cells/metabolism , Humans , Models, Biological , Protein Binding , Regulatory Sequences, Nucleic Acid , Transcription, Genetic , Transforming Growth Factor beta1/metabolism
14.
Cell Death Dis ; 3: e408, 2012 Oct 11.
Article in English | MEDLINE | ID: mdl-23059827

ABSTRACT

Although the retinoblastoma-susceptibility gene RB1 is inactivated in a wide range of human tumours, in colorectal cancer, the retinoblastoma protein (Rb) function is often preserved and the RB locus even amplified. Importantly, we have previously shown that Rb interacts with the anti-apoptotic Bcl-2 associated athanogene 1 (BAG-1) protein, which is highly expressed in colorectal carcinogenesis. Here we show for the first time that Rb expression is critical for BAG-1 anti-apoptotic activity in colorectal tumour cells. We demonstrate that Rb expression not only increases the nuclear localisation of the anti-apoptotic BAG-1 protein, but that expression of Rb is required for inhibition of apoptosis by BAG-1 both in a γ-irradiated Saos-2 osteosarcoma cell line and colorectal adenoma and carcinoma cell lines. Further, consistent with the fact that nuclear BAG-1 has previously been shown to promote cell survival through increasing nuclear factor (NF)-κB activity, we demonstrate that the ability of BAG-1 to promote NF-κB activity is significantly inhibited by repression of Rb expression. Taken together, data presented suggest a novel function for Rb, promoting cell survival through regulating the function of BAG-1. As BAG-1 is highly expressed in the majority of colorectal tumours, targeting the Rb-BAG-1 complex to promote apoptosis has exciting potential for future therapeutic development.


Subject(s)
DNA-Binding Proteins/metabolism , Retinoblastoma Protein/metabolism , Transcription Factors/metabolism , Apoptosis , Cell Nucleus/metabolism , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , DNA-Binding Proteins/antagonists & inhibitors , DNA-Binding Proteins/genetics , Humans , NF-kappa B/metabolism , RNA Interference , RNA, Small Interfering/metabolism , Retinoblastoma Protein/antagonists & inhibitors , Retinoblastoma Protein/genetics , Transcription Factors/antagonists & inhibitors , Transcription Factors/genetics , Tumor Cells, Cultured
15.
Acta Mater ; 60(6-7): 2568-2577, 2012 Apr.
Article in English | MEDLINE | ID: mdl-23470958

ABSTRACT

The solidification sequence of an AlMg4.7Si8 alloy is imaged in situ by synchrotron microtomography. Tomograms with (1.4 µm)3/voxel have been recorded every minute while cooling the melt from 600 °C at a cooling rate of 5 K min-1 to 540 °C in the solid state. The solidification process starts with the three-dimensional evolution of the α-Al dendritic structure at 590 °C. The growth of the α-Al dendrites is described by curvature parameters that represent the coarsening quantitatively, and ends in droplet-like shapes of the secondary dendrite arms at 577 °C. There, the eutectic valley of α-Al/Mg2Si is reached, forming initially octahedral Mg2Si particles preferentially at the bases of the secondary dendrite arms. The eutectic grows with seaweed-like Mg2Si structures, with increasing connectivity. During this solidification stage Fe-aluminides form and expand as thin objects within the interdendritic liquid. Finally, the remaining liquid freezes as ternary α-Al/Mg2Si/Si eutectic at 558 °C, increasing further the connectivity of the intermetallic phases. The frozen alloy consists of four phases exhibiting morphologies characteristic of their mode of solidification: α-Al dendrites, eutectic α-Al/Mg2Si "Chinese script" with Fe-aluminides, and interpenetrating α-Al/Mg2Si/Si ternary eutectic.

16.
Res Vet Sci ; 93(1): 42-5, 2012 Aug.
Article in English | MEDLINE | ID: mdl-21880339

ABSTRACT

Escherichia coli O115 has been isolated from healthy sheep and was shown to be associated with attaching-effacing (AE) lesions in the large intestine. Following previous observations of interactions between E. coli O157 and O26, the aim of the present study was to assess what influence an O115 AE E. coli (AEEC) would have on E. coli O157 colonisation in vitro and in vivo. We report that E. coli O115- and O157-associated AE lesions were observed on HEp-2 cells and on the mucosa of ligated ovine spiral colon. In single strain inoculum, E. coli O115 associated intimately with HEp-2 cells and the spiral colon in greater numbers than E. coli O157:H7. However, in mixed inoculum studies, the number of E. coli O115 AE lesions was significantly reduced suggesting negative interference by E. coli O157. Use of the ligated colon model in the present work has allowed in vitro observations to be extended and confirmed whilst using a minimum of experimental animals. The findings support a hypothesis that some AEEC can inhibit adhesion of other AEEC in vivo. The mechanisms involved may prove to be of utility in the control of AE pathovars.


Subject(s)
Bacterial Adhesion/physiology , Colon/microbiology , Escherichia coli Infections/veterinary , Escherichia coli/physiology , Sheep Diseases/microbiology , Animals , Colon/pathology , Escherichia coli Infections/microbiology , Escherichia coli Infections/pathology , Immunoenzyme Techniques/veterinary , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Microscopy, Electron, Transmission/veterinary , Sheep/microbiology , Sheep Diseases/pathology
17.
Oncogene ; 31(22): 2761-72, 2012 May 31.
Article in English | MEDLINE | ID: mdl-21963853

ABSTRACT

Understanding the mechanisms that promote aberrant tumour cell survival is critical for the determination of novel strategies to combat colorectal cancer (CRC). We have recently shown that the anti-apoptotic protein BAG-1, highly expressed in pre-malignant and CRC tissue, can potentiate cell survival through regulating NF-κB transcriptional activity. In this study, we identify a novel complex between BAG-1 and the p50-p50 NF-κB homodimers, implicating BAG-1 as a co-regulator of an atypical NF-κB pathway. Importantly, the BAG-1-p50 complex was detected at gene regulatory sequences including the epidermal growth factor receptor (EGFR) and COX-2 (PTGS2) genes. Suppression of BAG-1 expression using small interfering RNA was shown to increase EGFR and suppress COX-2 expression in CRC cells. Furthermore, mouse embryonic fibroblasts derived from the NF-κB1 (p105/p50) knock-out mouse were used to demonstrate that p50 expression was required for BAG-1 to suppress EGFR expression. This was shown to be functionally relevant as attenuation of BAG-1 expression increased ligand activated phosphorylation of EGFR in CRC cells. In summary, this paper identifies a novel role for BAG-1 in modulating gene expression through interaction with the p50-p50 NF-κB complexes. Data presented led us to propose that BAG-1 can act as a selective regulator of p50-p50 NF-κB responsive genes in colorectal tumour cells, potentially important for the promotion of cell survival in the context of the fluctuating tumour microenvironment. As BAG-1 expression is increased in the developing adenoma through to metastatic lesions, understanding the function of the BAG-1-p50 NF-κB complexes may aid in identifying strategies for both the prevention and treatment of CRC.


Subject(s)
Cell Transformation, Neoplastic/pathology , Colorectal Neoplasms/metabolism , Colorectal Neoplasms/pathology , DNA-Binding Proteins/metabolism , ErbB Receptors/metabolism , Gene Expression Regulation, Neoplastic , NF-kappa B p50 Subunit/metabolism , NF-kappa B/physiology , Transcription Factors/metabolism , Animals , Apoptosis , Blotting, Western , Cell Proliferation , Cells, Cultured , Chromatin Immunoprecipitation , Colorectal Neoplasms/genetics , Cyclooxygenase 2/genetics , Cyclooxygenase 2/metabolism , DNA-Binding Proteins/genetics , Electrophoretic Mobility Shift Assay , Embryo, Mammalian , ErbB Receptors/genetics , Fibroblasts , Humans , Immunoenzyme Techniques , Immunoprecipitation , Luciferases/metabolism , Mice , Mice, Knockout , NF-kappa B/antagonists & inhibitors , NF-kappa B p50 Subunit/genetics , Promoter Regions, Genetic , Protein Multimerization , RNA, Messenger/genetics , RNA, Small Interfering/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Transcription Factors/genetics , Transfection
18.
Br J Cancer ; 106(1): 157-65, 2012 Jan 03.
Article in English | MEDLINE | ID: mdl-22075945

ABSTRACT

BACKGROUND: Metastatic prostate cancer (PCa) has no curative treatment options. Some forms of PCa are indolent and slow growing, while others metastasise quickly and may prove fatal within a very short time. The basis of this variable prognosis is poorly understood, despite considerable research. The aim of this study was to identify markers associated with the progression of PCa. METHODS: Artificial neuronal network analysis combined with data from literature and previous work produced a panel of putative PCa progression markers, which were used in a transcriptomic analysis of 29 radical prostatectomy samples and correlated with clinical outcome. RESULTS: Statistical analysis yielded seven putative markers of PCa progression, ANPEP, ABL1, PSCA, EFNA1, HSPB1, INMT and TRIP13. Two data transformation methods were utilised with only markers that were significant in both selected for further analysis. ANPEP and EFNA1 were significantly correlated with Gleason score. Models of progression co-utilising markers ANPEP and ABL1 or ANPEP and PSCA had the ability to correctly predict indolent or aggressive disease, based on Gleason score, in 89.7% and 86.2% of cases, respectively. Another model of TRIP13 expression in combination with preoperative PSA level and Gleason score was able to correctly predict recurrence in 85.7% of cases. CONCLUSION: This proof of principle study demonstrates a novel association of carcinogenic and tumourigenic gene expression with PCa stage and prognosis.


Subject(s)
Biomarkers, Tumor/genetics , Prostatic Neoplasms/pathology , Disease Progression , Humans , Male , Prostatic Neoplasms/genetics , Prostatic Neoplasms/surgery , Real-Time Polymerase Chain Reaction
19.
J Dev Orig Health Dis ; 2(4): 250-5, 2011 Aug.
Article in English | MEDLINE | ID: mdl-22003431

ABSTRACT

Impaired flexibility in the use of substrates for energy production in the heart is implicated in cardiomyopathy. We investigated the effect of maternal protein restriction during pregnancy in rats on the transcription of key genes in cardiac lipid and carbohydrate metabolism in the offspring. Rats were fed protein-sufficient or protein-restricted (PR) diets during pregnancy. Triacylglycerol concentration in adult (day 105) heart was altered by maternal protein intake contingent on post-weaning fat intake and sex. mRNA expression of peroxisomal proliferator-activated receptor (PPAR)-α and carnitine palmitoyltransferase-1 was increased by the maternal PR diet in adult, but not neonatal, offspring. PPARα promoter methylation was lower in adult and neonatal heart from PR offspring. These findings suggest that prenatal nutrition alters the future transcriptional regulation of cardiac energy metabolism in the offspring through changes in epigenetic regulation of specific genes. However, changes in gene functional changes may not be apparent in early life.

20.
Opt Express ; 16(3): 1860-6, 2008 Feb 04.
Article in English | MEDLINE | ID: mdl-18542264

ABSTRACT

We demonstrate a novel Rayleigh interferometric noise mitigation scheme for applications in carrier-distributed dense wavelength division multiplexed (DWDM) passive optical networks at 10 Gbit/s using carrier suppressed subcarrier-amplitude modulated phase shift keying modulation. The required optical signal to Rayleigh noise ratio is reduced by 12 dB, while achieving excellent tolerance to dispersion, subcarrier frequency and drive amplitude variations.


Subject(s)
Artifacts , Electronics/instrumentation , Fiber Optic Technology/instrumentation , Interferometry/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Equipment Design , Equipment Failure Analysis , Reproducibility of Results , Sensitivity and Specificity
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