text: Study of freeze-thaw effects and CSF pH on tissue RNA integrity
  We have long suspected, on the basis of our tissue banking experience, that most of the molecular degradation that occurs in banked tissue is due to repeated freeze-thaw cycles, which occur due to improper handling during dissection for tissue retrieval or due to freezer malfunctions. Our freezers are currently protected by temperature-sensitive alarms that automatically telephone maintenance and tissue banking personnel when the temperature reaches a certain level. More protection is preferable, with CO2 tanks for backup cooling the optimum (but expensive) approach. We plan to systematically investigate the effects of thawing and refreezing on RNA integrity, by deliberately thawing and freezing small samples of brain tissue over varying time intervals and temperatures.
  
entities.text: ['tissue']
entities.type: Tissue
entities.entity_id: PMC-2493521-sec-21_T1
entities.text: ['tissue']
entities.type: Tissue
entities.entity_id: PMC-2493521-sec-21_T2
entities.text: ['tissue']
entities.type: Tissue
entities.entity_id: PMC-2493521-sec-21_T3
entities.text: ['tissue']
entities.type: Tissue
entities.entity_id: PMC-2493521-sec-21_T4
entities.text: ['tissue']
entities.type: Tissue
entities.entity_id: PMC-2493521-sec-21_T5
entities.text: ['brain tissue']
entities.type: Tissue
entities.entity_id: PMC-2493521-sec-21_T6
entities.text: ['samples']
entities.type: Tissue
entities.entity_id: PMC-2493521-sec-21_T7