periods Protocols

Category: Cloning Protocols

Protocol describes a method for DNA fragmentation by sonication. During sonication, DNA samples are subjected to hydrodynamic shearing by exposure to brief periods of sonication. DNA that has been sonicated for excessive periods of time is extremely difficult to clone. - [Read Fragmentation of DNA by Sonication Protocol]

Category: Cell Biology and Cell Culture: Flow Cytometry Protocols: Cell Sorting Protocols

This protocol has been established to maintain the efficient use of the AutoMACS cell sorter during periods of heavy use (e.g., three preparations of splenocytes from 16 spleens per week). Includes: Running the SAFE Clean Program; Clearing Debris. - [Read Maintenance of the AutoMACS Cell Sorter Protocol]

Category: Nucleic Acid Electrophoresis Protocols: Pulsed Field Gel Electrophoresis Protocols

Protocol for pulsed-field gel electrophoresis via contour-clamped homogeneous electric field gels. In CHEF gels, the electric field is generated from multiple electrodes, arranged in a square of hexagonal contour around the horizontal gel and clamped to predetermined potentials.  Using a combination of low field strengths, low concentrations of aragose, long switching intervals, and extended periods of electrophoresis, DNAs up to 5000 kb can be resolved. - [Read Pulsed-field Gel Electrophoresis via Contour-clamped Homogeneous Electric Field Gels Protocol]

Category: Transfection Protocols: Calcium Phosphate Transfection Protocols

This protocol describes two transfection methods for expressing GFP-tagged actin in primary neurons. The lipid reagent DOTAP (Roche Diagnostics) method produces actin-GFP-expressing hippocampal neurons that survive well during long periods in culture. The calcium phosphate method can be used to transfect neurons that have already been growing on coverslips in vitro. Transfected cells suitable for imaging can be obtained in cultures up to 15 days in vitro. - [Read Transfecting Cultured Hippocampal Neurons with an Actin-GFP Plasmid]

Category: Neuroscience Protocols: Neuronal Cell Culture Protocols

Protocol describes two transfection methods for expressing GFP-tagged actin in primary neurons.  The lipid reagent DOTAP (Roche Diagnostics) method produces actin-GFP-expressing hippocampal neurons that survive well during long periods in culture. - [Read Transfecting Cultured Hippocampal Neurons with an Actin-GFP Plasmid Protocol]

Category: Immunohistochemistry Protocols: Antigen Retrieval Protocols

Several methods have been developed to "retrieve" antigens that have been masked by fixation. The principle behind using the microwave oven method described here is to use extended periods of heat to break some of the subcellular structures that block antibody access. Be aware that any of the antigen retrieval methods should be avoided wherever possible, because they may introduce artifactual false-positive staining. - [Read Unmasking Hidden Epitopes Using the Microwave Oven Protocol]

Category: Immunohistochemistry Protocols: Antigen Retrieval Protocols

The principle behind the pressure cooker method described here is to use extended periods of heat to break some of the subcellular structures that block antibody access. This approach is appropriate for handling specimens on glass slides. The major advantages of the pressure cooker method are the ability to handle a large number of slides simultaneously, the convenience of using metal racks, and the avoidance of any hot spots that are found in the microwave. - [Read Unmasking Hidden Epitopes Using the Pressure Cooker Protocol]