Study of optical parameters of the nucleoli under the effect of transcription inhibitors by coherent phase microscopy

The use of coherent phase microscopy for online quantitative registration of nucleolar reaction to transcription inhibition is validated. Reduction of phase thickness of the nucleoli was detected during the first minutes of the experiment; 30 min after addition of the drug rarefaction zones predominated and areas of condensation were seen. These changes reflect the dynamics of disorders in the nucleolar ultrastructure during transcription inhibition.

A study of demyelination of nerve fibers using dynamic phase contrast microscopy

Dynamic phase microscopy was used for evaluation of changes in myelinated axon segment in the paranodal region of nerve fibers during demyelination. Normally paranodal myelin sheath is characterized by regular oscillations of the optical path difference with frequences of 4.2 and 6.7 Hz. Demyelination decreased the amplitude and conduction velocity in nerve fibers and shifted the characteristic frequencies of optical path difference oscillations to 2.8, 3.2, and 11 Hz. These shifts of optical path difference frequencies probably resulted from disturbances in the state of charged phospholipids and a decrease in the level of bound Ca(2+)during demyelination of nerve fiber.