Transfection of hypertrophic cardiac myocytes in vitro with (99)Tc(m)-labeled antisense miR208b oligonucleotide / 南方医科大学学报

<p><b>OBJECTIVE</b>To test the efficiency of transfecting (99)Tc(m)-labeled anti-miR208b oligonucleotide into early hypertrophic cardiac myocytes in vitro.</p><p><b>METHODS</b>The anti-oligonucleotide targeting miR208b (AMO) was synthesized and modified with LNA followed by conjugation with N-hydroxysuccinimidyl S-acetyl-meraptoacetyl triglycine (NHS-MAG3) and radiolabeling with (99)Tc(m). NHS-MAG3-LNA-AMO and labeled AMO were purified with Sep-Pak C18 column chromatography, and the former was examined for UV absorption at the 260 nm using Gene Quant DNA/RNA calculator. The labeling efficiency, radiochemical purity, stability and molecular hybridization activity were analyzed. An angiotensin II-induced cell model of hypertrophic cardiac myocytes was transfected with (99)Tc(m)-NHS-MAG3-LNA-AMO via liposome, and the relative expression of miRNA208b and retention ratio of the labeled AMO in early hypertrophic cells were determined.</p><p><b>RESULTS</b>The labeling efficiency and radiochemical purity of the labeled AMO after purification exceeded 84% and 86%, respectively. The radio- chemical purities of the labeled AMO incubated in serum and normal saline for 12 h were both higher than 80%, and the labeled AMO showed a capacity to hybridize with the target gene. In the hypertrophic model of cardiac myocytes, the retention ratio of labeled AMO at 6 h was higher than 20%.</p><p><b>CONCLUSION</b>The (99)Tc(m)-labeled antisense probe can be efficiently transfected into hypertrophic cardiac myocytes in vitro, which provides an experimental basis for subsequent radionuclide imaging studies.</p>

Association between iodine intake and treatment outcomes of radioiodine remnant ablation in patients with papillary thyroid cancer / 中华核医学与分子影像杂志

Objective To evaluate the association between iodine intake and treatment outcomes of radioiodine remnant ablation in patients with papillary thyroid cancer (PTC),and to investigate the determinants related to the ablation efficacy.Methods A total of 95 PTC patients (28 males,67 females;average age 39.8 years) without distant metastases from January 2013 to May 2014 were enrolled in this retrospective study.All patients underwent total thyroidectomy and 2-4 weeks of low iodine diet (LID) before initial 131I therapy.Patients were divided into 3 groups according to urinary iodine excretion (UIE):moderate-severe iodine deficiency group (0＜UIE＜50 μg/L,n =30),mild iodine deficiency group (50 μg/L≤UIE＜100 μg/L,n =26),adequate iodine group (100 μg/L ≤ UIE ＜ 300 μg/L,n =39).Patients were followed up for 3-6 months after radioiodine ablation,successful ablation was defined as no visible uptake in the thyroid bed on diagnostic 131I whole body scan and Tg level ＜2 μg/L (with negative TgAb),or no visible uptake in thyroid bed on posttreatment 131I whole body scan.x2 test,two-sample t test,Mann-Whitney u test and logistic regression analysis were performed.Results In all,84.2％ (80/95)of patients were successfully ablated.The successful rates in the three iodine intake groups were 96.7％ (29/30),84.6％ (22/26) and 74.4％ (29/39),respectively,with significant difference (x2=7.374,P＜0.05).Univariate analysis revealed that UIE,pre-treatment TSH,pre-treatment Tg and the amount of remnant thyroid tissue at ablation affected ablation efficacy (x2 =7.374,t =2.037,z =-2.966,x2 =4.144,all P＜0.05).Logistic regression showed that the level of pre-treatment Tg (P ＜ 0.05) and iodine intake (P ＜ 0.05) were independent factors of ablation efficacy.Conclusion Iodine intake before 131I remnant ablation is one of the important factors affecting treatment outcomes.Thyroid remnant could be more successfully ablated if reasonable LID protocols be adopted according to the iodine nutritional status before treatment.