AIM:To evaluate the effect of mycoplasma on the rRNA composition of mature ribosomes in human cell lines.METHODS:We isolated ribosome nascent-chain complex ( RNC) from multiple mycoplasma-positive-negative human cell lines.RNC-RNA was acquired from each cell line through RNA extraction, followed by agarose gel separation, fluorescent visualization and gray-scale value measurements on the rRNA bands.Western blot analysis was performed to in-vestigate the MAPK pathway alterations.RESULTS:In various human cell lines derived from different tissues, we found that as compared with mycoplasma-negative cells, mycoplasma-positive cells showed aberrant RNC-rRNA band patterns, featured by the decreases in 28S and 18S eukaryotic rRNAs and the increases in 16S and other unknown prokaryotic rRNAs.When cultured without ciprofloxacin, mycoplasma-negative HBE cells acquired mycoplasma contamination as ob-served with such characteristic abnormal rRNA bands.The ciprofloxacin treatment was able to recover the RNC-rRNA bands of the mycoplasma-contaminated cells to the normal pattern.The results of Western blot analysis on total and phos-phorylated proteins indicated that p38 pathway was significantly deactivated in mycoplasma-infected A549 cells, while ERK1/2 pathway was not significantly altered.CONCLUSION:Mycoplasma contamination severely alters the RNC-rRNA composition via p38 MAPK pathway, thus seriously impacting on the host cell translational behaviors.

OBJECTIVE: To study the radition injury of tracheal mucous membrane tissue after interstitial implanted radioactive 125I in normal rabbit,improve the safety of clinical application. METHOD: Sixty New Zealand rabbits, weighing 2.15-2.30 kg, were randomly divided into 1 w, 1 m, 2 m, 4 m and the control group, the control group was further divided into four subgroups. The 0.8mCi 125I seeds were implanted into the tissue by the first tracheal ring in the treatment groups and nonradioactive seeds were implanted in the control group. Taking the tracheal mucous membrane tissue for pathological examination by HE staining to observe the mucosal injury and VEGF, Pan-Cadherin immunohistochemical staining to observe the expression in differernt time. RESULT: Immunohistochemical staining: VEGF and Pan-Cadherin have statistically significant differences in the expression on different time, the expression is dynamic. CONCLUSION The expression of VEGF and Pan-Cadherin reflect the radioactive 125I seed has little influence on normal trachea tissue and the damage can be repaired by the regeneration of the basal cell.
Animals ; Brachytherapy ; adverse effects ; Iodine Radioisotopes ; adverse effects ; Rabbits ; Radiation Injuries ; pathology ; Trachea ; pathology ; radiation effects