67 research outputs found
Towards liver-directed gene therapy: Retrovirus-mediated gene transfer into human hepatocytes
Liver-directed gene therapy is being considered in the treatment of inherited metabolic diseases. One approach we are considering is the transplantation of autologous hepatocytes that have been genetically modified with recombinant retroviruses ex vivo. We describe, in this report, techniques for isolating human hepatocytes and efficiently transducing recombinant genes into primary cultures. Hepatocytes were isolated from tissue of four different donors, plated in primary culture, and exposed to recombinant retroviruses expressing either the LacZ reporter gene or the cDNA for rabbit LDL receptor. The efficiency of gene transfer under optimal conditions, as determined by Southern blot analysis, varied from a maximum of one proviral copy per cell to a minimum of 0.1 proviral copy per cell. Cytochemical assays were used to detect expression of the recombinant derived proteins, E. coli β-galactosidase and rabbit LDL receptor. Hepatocytes transduced with the LDL receptor gene expressed levels of receptor protein that exceeded the normal endogenous levels. The ability to isolate and genetically modify human hepatocytes, as described in this report, is an important step towards the development of liver-directed gene therapies in humans.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45540/1/11188_2005_Article_BF01233625.pd
Residual electrostatic charge and charge distributions on fly ashes produced by the combustion of Australian coals
Electrostaticcharges on flyash particles, measured in situ at several Australian power stations have indicated variations in magnitude and distribution, which can be related to difficulties experienced in cleaning the fabric filters downstream. Measurements made in situ at three Australian power stations, Eraring, Tallawarra and Bayswater showed a considerable variation in charge and distribution with Tallawarra having the largest mean charge (−1.25 μC/g) with a narrow distribution and Eraring having the smallest mean charge (−0.35 μC/g) with a wide distribution. Laboratory tests performed immediately after collection of isokinetic samples from the power stations resulted in lower mean charges (−0.11 μC/g for the Eraring ash) with similar trends in distribution. Further measurements of the charge on the flyashes taken over several months showed that an inherent charge on the ash particles remains indefinitely (−0.018 μC/g for the Eraring ash and −0.25 μC/g for the Tallawarra ash). It appears that this inherent charge cannot be dissipated by contact with other particles or solid materials
- …