ABSTRACT
Objective To investigate the feasibility and preventive effect of benign esophageal restenosis by binding 125I seeds to upper esophageal stent through animal experiments.Methods Eight 125I seeds were evenly bound to upper normal esophageal stents for the animal experiments.A total of 32 beagle dogs were randomly assigned to 2 groups:experimental group,implanted with esophageal stents with eight 125I seeds (33.3 MBq),and the control (stents without 125I seeds).Four dogs of each group were killed at the 1 st,2nd,4th,and 8th week after imaging studies.The tissue of 2 cm upper stent underwent pathology analysis.Results All the novel stents were successfully implanted.No radioactive leak was detected by ECT.The lumen diameter of the top stent showed the tract gradually narrowed and at the 4th and 8th weeks,the experiment group narrowed more seriously compared with the control group and the difference was statistically significant (P ＜ 0.05).PCNA,ot-SMA mean optical density were significantly different in the 4th week.Both hydroxyproline and total amino acid increased progressively,with significant difference at the 4th and 8th weeks.The macroscopic and optical findings of the trachea and major vessels were basically the same in both groups.Conclusion The novel stent is feasible and safe for preventing benign esophageal restenosis and preventing benign esophageal stent restenosis.
ABSTRACT
Objective To investigate the effect and underlying mechanism of single,fractioned and continuous low dose rate radiation on CL187 colorectal cancer cell line.Methods CL187 cells were exposed to 6 MV X-rays at a high dose rate of 4 Gy/min and 125Ⅰ seed at a low dose rate of 2.77 cGy/h with three groups:single dose radiation group (SDR),fractioned dose radiation group (FDR) by 2 Gy/f,and continuous low dose rate radiation group (CLDR).The radiation doses were 0,2,4 and 8 Gy.Total cell number and cell viability were determined by trypan blue.Clone forming assay was used to evaluate the cell proliferation ability.The percentage of apoptosis cells was analyzed by flow cytometry.Western blot was used to detect the protein expression levels of PHLPP2,PTEN and Bax.Results Compared with SDR and FDR groups,the total cell number and survival fraction of CLDR group decreased.The relative biological effect (RBE) for 125Ⅰ seeds compared with 6 MV X-rays was 1.41.The percentage of apoptosis cells of CLDR group was significantly increased (t =-15.08,-11.99,P ＜ 0.05).The expression level of Bax increased in CLDR group,while no obvious changes were observed on PHLPP2 and PTEN among three groups.Conclusions The expression level of PHLPP2 increaseS in SDR,FDR and CLDR group,while it seems that it was not influenced by dose rate.The expression level of Bax increased in three groups,while more colorectal CL187 cells in CLDR group may be killed due to the increase of Bax expression.
ABSTRACT
ObjectiveTo evaluate the efficacy, feasibility and safety of CT guided percutaneous 125Ⅰ seeds implantation in elderly patients of stage Ⅰperipheral non-small cell lung cancer ( NSCLC ).MethodsClinical data of 16 elderly peripheral stage Ⅰ NSCLC patients ( 10 squamous carcinoma and 6adenocarcinoma;13 stage ⅠA and 3 stage ⅠB ) who received radioactive 125Ⅰ seeds implantation because of refusal or being unsuited to operation or external radiotherapy were retrospectively analyzed. Prescribed dose was 140 - 160 Gy. Under CT guidance, 125Ⅰ seeds were implanted percutaneously into tumors for interstitial radiotherapy according to treatment plan system. ResultsMean number of 125Ⅰ seeds each patient received was21.1. 12 complete response (CR) and 4 partial response (PR) were achieved. Total response rate ( CR + PR) was 100％. 100％ patients completed 10 to 56 months of follow-up, 15, 13, 8 and 6 patients completed 1-, 2-, 3-and 4-years'follow-up, respectively. The median local progression free time was 14months. The 1-,2-,3-and 4-year overall survival rate were 60％, 54％, 50％ and 33％, respectively (median:14 months). 7 cases died of non-tumor disease and 5 died of metastasis. No severe complications were observed. ConclusionsCT guided 125Ⅰ seeds implantation is a safe, reliable and effective radical treatment method for elderly stage Ⅰ peripheral NSCLC patients, who refuse to or are unsuitable to operation or external radiotherapy.