摘要:
The present invention provides a method for purifying bacterial minicells that involves subjecting a sample containing minicells to density gradient centrifugation in a biologically compatible medium. The method optionally includes a preliminary differential centrifugation step and one or more filtration steps. The invention also provides a method for purifying bacterial minicells in which a sample containing minicells is subjected to a condition that induces parent bacterial cells to adopt a filamentous form, followed by filtration of the sample to separate minicells from parent bacterial cells. The inventive methods optionally include one or more steps to remove endotoxin from purified minicell preparations, and/or treatment of purified minicell preparations with an antibiotic. Additionally, the invention provides purified minicell preparations, prepared according to the foregoing methods, and containing fewer than about 1 contaminating parent bacterial cell per 107, 108, 109, 1010, or 1011 minicells.
摘要:
An egg freezing and storing instrument has an egg freezing and storing tube made of a liquid nitrogen-resistant material; and a metal cylindrical protection member for protecting the tube. The tube has a body part; and an egg-storing small-diameter part having an inner diameter of 0.1 mm to 0.5 mm. The tube can be heat-sealed at a front side of the small-diameter part and at a rear side of the body part. The cylindrical protection member has a tubular part for accommodating a front side of the small-diameter part of the tube; and a semi-tubular part for accommodating a portion of the small-diameter part not accommodated in the tubular part and a front portion of the body part.
摘要:
The invention relates to a method of manufacturing a culture medium on which plants can be grown. The method comprises mixing organic and/or inorganic particulate base materials with a thermoplastic, biologically degradable, binding agent, heating the mixture to make it at least semi-fluid, and then cooling the mixture to solidify it.
摘要:
A method for in vitro cultivation of cells, which grow on a culture surface, wherein the cells are sown on culture surfaces (1) and are cultivated in a culture medium, whereby the culture surface is continually or periodically expanded, without being removed from the culture medium. To expand the culture surface, the cells are not detached from the culture surface and the culture surface between the cells is expanded. However, at least part of the cells can be detached and the culture surface can be expanded by the flooding of additional culture surface areas. The culture surface of an example device for cell cultivation consists of one side of an expanding membrane (6), which is expanded by modifying the pressure on the other side. The cell cultivation can be carried out without manual passaging. The cells are subjected to less stress than in known cell cultivation methods and the method can be automated more easily.
摘要:
A freeze-dried biocompatible matrix that includes plasma proteins that are useful as implants for tissue engineering as well as in biotechnology. Methods of producing the matrix are also provided. Mechanical and physical parameters can be controlled by the use of auxiliary components or additives which may be removed after the matrix is formed in order to improve the biological properties of the matrix. These matrices may be used clinically per se or as a cell-bearing implant.
摘要:
The invention relates to a new nullgene-switchnull (cumate-inducible switch) for mammalian cells. This switch is as useful in the development of expression systems and cell-based assays for functional genomics as in the generation of viral vectors for gene therapy.
摘要:
Methods and compositions for modulating mucin secretion by respiratory system cells are provided. In the subject methods, an effective amount of an hCLCA2 (or homolog thereof) modulatory agent is contacted with the cell to modulate mucin secretion, e.g., decrease or increase mucin secretion, by the cell. The subject methods find use in a variety of different applications, including the treatment of disease conditions associated with respiratory system mucin secretion, e.g., mucin hyper- or hyposecretion. Also provided are methods of screening for respiratory system mucin secretion modulatory agents. Finally, mCLCA4 and non-human homologs thereof, as well as nucleic acid compositions encoding the same, are provided.
摘要:
The present invention relates to protein engineering for production of analogs of MB-1. MB-1 analogs are more stable to different biochemical conditions than the native protein, and allow for improving the supplying of essential amino acids to human and animals. De novo synthesis of MB-1 analogs is principally targeted to enhance availability of essential amino acids required for farm animal production or human health.
摘要:
A system is provided to enable maintaining cell viability in a microfluidic device and for monitoring an activity of a cell in a microfluidic device. The microfluidic device may include a cell duct plate, a flow channel plate, a porous membrane bounding at least a portion of each of the cell duct and the flow channel plate. The system may include, in addition to the microfluidic device, a pump, a controller, and a sensor.
摘要:
Disclosed are methods and compositions useful, e.g., for controlling the valency of display proteins during display library screenings and selections. In one embodiment, they are applicable to phage and phage libraries that are based on bacteriophage, e.g., filamentous bacteriophage.