2,127 research outputs found
Similarities and differences between the E5 oncoproteins of bovine papillomaviruses type 1 and type 4: Cytoskeleton, motility and invasiveness in E5-transformed bovine and mouse cells
Bovine papillomaviruses (BPVs) are oncogenic viruses. In cattle, BPV-1/2 is associated with urinary bladder cancer and BPV-4 with upper GI tract cancer. BPV E5 is a small hydrophobic protein localised in the endoplasmic reticulum (ER) and Golgi apparatus (GA). E5 is the major transforming protein of BPVs, capable of inducing cell transformation in cultured mouse fibroblasts and, in cooperation with E7, in primary bovine cells. E5-induced cell transformation is accompanied by activation of several cellular protein kinases, including growth factor receptors, and alkalinisation of endosomes and GA. We have reported that BPV E5 causes swelling and fragmentation of the GA and extensive vacuolisation of the cytoplasm. We now show that E5 from both BPV-1 and BPV-4 disturbs the actin cytoskeleton and focal adhesions in transformed bovine cells, where these morphological and behavioural characteristics are accompanied by hyperphosphorylation of the cellular phosphotyrosine kinase c-src. Both BPV-1 and BPV-4 E5 increase the motility of transformed mouse cells, but only BPV-1 E5 causes transformed mouse cells to penetrate a matrigel matrix. BPV-1 transformed mouse cells, but not BPV-4 transformed mouse cells, have hyperhpsphorylated c-src
A new technique for evaluating mesospheric momentum balance utilizing radars and satellite data
Copyright © 2000 European Geosciences UnionA new method for evaluating momentum balance in the mesosphere using radar and satellite data is presented. This method is applied to radar wind data from two medium frequency installations (near Adelaide, Australia and Christchurch, New Zealand) and satellite temperature data from the Improved Stratospheric and Mesospheric Sounder (ISAMS). Because of limitations in data availability and vertical extent, the technique can only be applied to evaluate the momentum balance at 80 km above the radar sites for May 1992. The technique allows the calculation of the residual terms in the momentum balance which are usually attributed to the effects of breaking gravity waves. Although the results are inconclusive above Adelaide, this method produces values of zonal and meridional residual accelerations above Christchurch which are consistent with expectation. In both locations it is apparent that geostrophic balance is a poor approximation of reality. (This result is not dependent on a mismatch between the radar and satellite derived winds, but rather is inherent in the satellite data alone.) Despite significant caveats about data quality the technique appears robust and could be of use with data from future instruments
Some Combinatorial Properties of Hook Lengths, Contents, and Parts of Partitions
This paper proves a generalization of a conjecture of Guoniu Han, inspired
originally by an identity of Nekrasov and Okounkov. The main result states that
certain sums over partitions p of n, involving symmetric functions of the
squares of the hook lengths of p, are polynomial functions of n. A similar
result is obtained for symmetric functions of the contents and shifted parts of
n.Comment: 20 pages. Correction of some inaccuracies, and a new Theorem 4.
Electricity Network Scenarios for Great Britain in 2050. Final Report for Ofgems LENS Project
An expert opinion: Rehabilitation options for people with polyneuropathy
Polyneuropathies encompass a number of diseases of the peripheral nerves. Causes vary, and some types of polyneuropathy have a chronic disease course, and some have acute onset. Polyneuropathies, such as Guillain Barré Syndrome, improve after acute deterioration, but some people are left with longer term disability.
Physical management to manage longer term impairments and maintain function, are gathering evidence of efficacy, though trials remain small in number and size. Exercise trials show some positive improvements in proximal muscle strength, aerobic capacity, balance and distal strength in children. People with polyneuropathy often present with distal weakness and joint malalignment. Orthotics interventions may address these impairments and can vary from ankle foot orthoses to insoles. Weakness and sensory impairment also lead to altered hand function which can be addressed by adaptive strategies and exercise. People with polyneuropathies can beneft from rehabilitation interventions through addressing the impact of impairments and compensatory strategies necessary for optimised function
Src/FAK-mediated regulation of E-cadherin as a mechanism for controlling collective cell movement Insights from in vivo imaging
Recent advances in confocal and multi-photon microscopy, together with fluorescent probe development, have enabled cancer biology studies to go beyond the culture dish and interrogate cancer-associated processes in the complex in vivo environment. Regulation of the tumor suppressor protein E-cadherin plays an important role in cancer development and progression, and may contribute to the decision between ‘single cell’ and ‘collective invasion’ in vivo. Mounting evidence from in vitro and in vivo experiments places the two nonreceptor protein tyrosine kinases Src and Focal Adhesion Kinase at the heart of E-cadherin regulation and the crosstalk between integrins and cadherins. Here we discuss recent insights, attained using high-resolution fluorescent in vivo imaging, into the regulation of E-cadherin and collective invasion. We focus on the regulatory crosstalk between the Src/FAK signaling axis and E-cadherin in vivo
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