Evaluation of Prognosis of Juvenile Differentiated Thyroid Carcinoma.

Differentiated thyroid carcinoma (DTC) in juvenile patients is often an extensive and aggressive disease with a high frequency of recurrence. However, the prognosis is excellent, with a low mortality rate even when advanced disease is present, although prognostic factors and treatment strategy remain uncertain. Between April 2004 and March 2017, 33 juvenile patients (< 30 years old) were diagnosed with DTC and treated at our institution. We retrospectively investigated prognosis and factors including sex, reason for discovery, treatment, pathological factors and treatment progress to clarify the risk factors. All patients underwent curative surgical treatment. Pathologically, lymph node metastasis was identified in 25 patients (75%). Thirteen patients (39%) had bilateral cervical metastasis. In addition, 9 (27%) had more than 10 metastatic lymph nodes. The 2 patients with more than 20 metastatic lymph nodes were treated with radioactive iodine (RAI). Five patients (15%) had local recurrences and received surgery. There have been no further recurrences or deaths. However, no factors were determined to significantly predict the recurrence of juvenile DTC. Local recurrent disease was treated with surgery and/or RAI until remission, and survival was excellent in juvenile DTC.

DNA mismatch detection using a pyrene-excimer-forming probe.

A pyrene-excimer-forming probe allowed the easy and sensitive detection of a single base mismatch in target DNA. This was due to the faster strand exchange rate compared to a fully-matched target.

Molecular sensing by pyrene excimer signal of fluorescent DNA aptamer.

The pyrene excimer label (2) has been incorporated into the adjacent residue to the binding site of anti-ATP DNA aptamer. The fluorescent aptamer exhibited the specific fluorescence signal only in the presence of ATP.

Bis-pyrene labeled DNA aptamer as an intelligent fluorescent biosensor.

The site-directed incorporation of bis-pyrenyl fluorophore into anti-ATP DNA aptamer results in a creation of an intelligent fluorescent sensor with high signal intensity and specificity for detecting the target ligand in a homogeneous system.

Bis-pyrene-labeled oligonucleotides: sequence specificity of excimer and monomer fluorescence changes upon hybridization with DNA.

The design, synthesis, and properties of a new pyrene excimer-forming probe of DNA have been described. 2,2-(Aminomethyl)propanediol was converted by the reaction with 1-pyrenebutylic acid to bis-pyrene-modified propanediol as a fluorescent non-nucleosidic linker. The bis-pyrene-modified linker can be incorporated via phosphoramidite chemistry into the 5'-terminal or internal positions of oligonucleotides (ODNs). The terminally modified ODNs showed almost similar affinity for complementary DNA when compared with the corresponding unmodified ODNs. The duplexes containing the bis-pyrene in the main chain exhibited higher melting temperatures relative to the corresponding duplexes containing propanediol linker at the same position. The UV and CD spectral studies indicate that the stacking interactions between the pyrene and DNA bases occur in the internally modified duplex and do not in the terminally modified duplex. The bis-pyrene modified linker itself displays excimer (E at 480 nm) and monomer (M at 380 nm) emission in a quantum yield (QY) of 0.17 and the E/M intensity ratio of 15. Incorporation of this linker into the terminal or internal positions of ODNs reduced the QY (0.003-0.009) and the E/M ratio (0.3-0.8). While small changes in the QY and E/M ratio was obtained in binding of the internally labeled ODNs to DNA, up to 27-fold increase in the QY and 17-fold increase in the E/M ratio was observed upon hybridization of the terminally labeled ODNs with DNA. The excimer and monomer fluorescence changes were found to be sensitive to a mismatch base present in the target DNA. The bis-pyrene-modified ODNs thus provide a sequence-sepcific fluorescent probe of DNA.