Impact of Cold Ischemic Time and Freeze-Thaw Cycles on RNA, DNA and Protein Quality in Colorectal Cancer Tissues Biobanking.

Tissue-derived RNA, DNA and protein samples become more and more crucial for molecular detection in clinical research, personalized and targeted cancer therapy. This study evaluated how to biobanking colorectal tissues through examining the influences of cold ischemic time and freeze-thaw cycles on RNA, DNA and protein integrity. Here, 144 pairs of tumor and normal colorectal tissues were used to investigate the impact of cold ischemic times (0-48h) on RNA, DNA and protein integrity at on ice or room temperature conditions. Additionally, 45 pairs of tissues experienced 0-9 freeze-thaw cycles, and then the RNA, DNA and protein quality were analyzed. On ice, RNA, DNA and protein from colorectal tumor and normal tissues were all stable up to 48h after surgery. At room temperature, RNA in colorectal tumor and normal tissues began to degrade at 8h and 24h, respectively. Meanwhile, the tumor tissues DNA degradation occurred at 24h after surgery at room temperature. Similarly, the protein expression level of tumor and normal tissues began to change at 24h after the surgery at room temperature. Interestingly, tissue RNA and DNA remained stable even after 9 freeze-thaw cycles, whereas the proteins levels were remarkably changed after 7 freeze-thaw cycles. This study provided a useful evidence on how to store human colorectal tissues for biobanking. Preserving the surgical colorectal tissue on ice was an effective way to prevent RNA, DNA and protein degradation. Importantly, more than 7 repeated freeze-thaw cycles were not recommended for colorectal tissues.

[Probe into characteristics of Taraxacum mongolicum ultramicro-power].

OBJECTIVE: To observe and study the tissue characteristics of T. mongolicum ultramicro-power and dissolving-out characteristics of effective compositions. METHOD: By microscopic observation and thin-layer chromatography. RESULT: Nearly all cell walls of T. mongolicum are broken and dissolving-out characteristics of effective compositions are remarkably improved, after it is ultramicro-porphyrized.

[Study on pharmacology of ultra-fine particles compound Rehmannia].

OBJECTIVE: To observe pharmacological difference between ultra-fine particles of six ingredient Rehmannia pill and traditional six ingredient Rehmannia pill. METHOD: Pharmacokinetic index was measured by death rate, and pharmacology actions were compared by anti-fatigue, hypoglycemic, clearance rate of charcoal particle, hypoxia resistance and serum hemolysin concentration experiment. RESULT: Dose-effection was significant and pharmacology actions were more than traditional six ingredient Rehmannia pill in six ingredient Rehmannia pill. CONCLUSION: Ultra-fine particles of six ingredient Rehmannia pill are better than traditional six ingredient Rehmannia pill in bioavailability and pharmacology actions, and the weight of pill is reduced while efficacy is enhenced by ultra-fine particles.