Abstract: A plug assembly having an insert having an aperture extending from a first end of the insert to a second end, the aperture defining a tapered female thread tapering from a larger diameter towards the first end to a smaller diameter towards the second end, and a plug having a head portion and a base portion, and a tapered male thread located between the head portion and the base portion, wherein the plug is adapted to screw into the insert to secure the plug in the insert.

Abstract: This invention relates to methods for the cultivating cells, and in particular to methods for propagating viruses.

Abstract: An insoluble mammalian protein is extracted from transformed bacteria expressing the mammalian protein while avoiding irreversible insolubilization of bacterial host proteins by homogenizing the fermentation broth, centrifuging the homogenized broth and removing the supernatant liquid for the inclusion body containing pellet. In another embodiment, the pH of the homogenized broth is adjusted to 2.0 prior to centrifugation. The acidified broth is then centrifuged, and the pellet is resuspended in buffer, homogenized again, and the inclusion body is isolated by centrifugation.