These materials persist in the peritoneal cavity, where they induce chronic inflammation during the long periods before plasmacytomas develop.
Such plasmacytomas appear to arise from B cells carrying chromosomal translocations that affect c-myc transcription.
OBJECTIVE Because silicone gels are in widespread medical use and share many of the characteristics of other materials known to be inducers of plasmacytomas, we wished to determine their capacity to induce plasmacytomas in mice.
GREUTATE - SFATURI PENTRU A SLABI SANATOS
Mice were examined at least once every 2 weeks for plasamacytoma pierderea în greutate of abdominal tumor or weight loss and screened every weeks for peritoneal plasmacytoma cells by peritoneal lavage. Tissues were examined by histologic and immunohistochemical techniques.
Metaphase chromosome spreads were made from ascitic plasmacytomas without Colcemid treatment, and metaphase plates were G-banded according to standard techniques.
The t 12;15 or t 6;15 translocation chromosomes were identified under the microscope in at least five metaphase plates of high banding quality.
Mice were autopsied days after the injection of test material. Gas chromatography and mass spectrometry were utilized to determine the composition of the silicone oil and silicone gel used in the injections.
Neither corn oil used as a control nor centistoke or 12,centistoke dimethylpolysiloxane induced plasmacytomas in these mice. The plasmacytomas were transplantable in syngeneic hosts.
Cytogenetic studies of 41 silicone-induced plasmacytomas showed that 30 had t 12;15 translocations, eight had t 6;15 translocations, and three had no translocations. Further studies will be required to determine which of the components of these gels are the active materials.
Creșterea nivelului de calciu din sânge hipercalcemie.