Effect of previous administration of potassium iodine and different durations of low iodine diets for radioiodine therapy on the treatment of Graves' disease in iodine-rich areas.

PURPOSE: To examine whether adherence to a low-iodine diet (LID) enhances the therapeutic efficacy of radioiodine therapy (RAI) in Graves' hyperthyroidism (GH) in iodine-rich areas. METHODS: We retrospectively evaluated 185 patients with GH from Aichi (n = 114) and Hokkaido (n = 71) Prefectures. Patients aged ≥ 18 years with GH who underwent RAI between December 2012 and March 2022 were divided into subgroups based on pretreatment with anti-thyroid drug (ATD) or potassium iodide (KI). Patients were followed up with LID from 18 days (group A) or 7 days (group H) before RAI to 3 days after RAI. The dose of radioactive iodine 131 (131I) was adjusted to deliver > 100 Gy to the thyroid. The associations between urinary iodine concentration on UIC2 vs. 24hRU and UIC2 vs. the 1-year RAI success rate (SR) were investigated. RESULTS: Compared with UIC1, UIC2 was significantly decreased in all subgroups (P < 0.01). An inverse correlation between UIC2 and 24hRU was observed in the four groups; however, the difference was insignificant. The SR in groups A and H was 85% and 89%, respectively. Univariate analysis revealed no association between UIC2 and SR in each group. Additionally, stratification of the 185 patients into quartiles using UIC2 yielded no significant differences in SR (p = 0.79). CONCLUSIONS: LID sufficiently reduced UIC in patients undergoing RAI. Although a lower UIC2 may increase 24hRU, it did not increase the success of RAI. The benefit of LID in enhancing the efficacy of RAI in GH treatment remains uncertain.

Synthesis of Photoreactive Poly(ethylene oxide)s for Surface Modification.

Photoreactive polymers that generate active species upon irradiation with light are very useful for modifying the surfaces of substrates. However, water solubility decreases as the number of photoreactive functional groups on the polymer increases because most photoreactive functional groups are hydrophobic. In order to improve the hydrophilicity of the photoreactive polymer, we synthesized polyethylene glycol-based photoreactive polymers bearing hydrophobic azidophenyl groups on their side chains. Because of the hydrophilicity of the ethylene glycol main chain, polymers with large numbers of azidophenyl groups were solubilized in protic solvents compared to hydrophobic alkylene chain-based polymers prepared by radical polymerization of methacrylate monomers. Polymers were immobilized on various substrates by irradiation with ultraviolet light and were shown to suppress nonspecific interactions between proteins and cells on the substrate. We conclude that such polymers are useful, highly water soluble antifouling agents.

[Use of Flash Glucose Monitoring during the Perioperative Period of Cardiac Surgery in a Patient with Type 1 Diabetes Mellitus].

FreeStyle Libre (flash glucose monitoring) is useful to control the blood sugar levels of outpatients with diabetes. We used FreeStyle Libre for a patient with type 1 diabetes mellitus during the perioperative period of cardiac surgery except during and just after surgery. We adjusted the insulin amount according to the glucose level of the device before surgery and prevented prolonged hypoglycemia. After surgery, we could also adjust the blood sugar levels using the device until discharge. All data were within zones A and B of the Clarke error grid analysis when referred to as arterial blood sugar levels in the intensive care unit. In the general ward after surgery, 95% of the data referred to as venous blood sugar levels were within zones A and B. FreeStyle Libre was useful for adjusting the amount of insulin for a patient with type 1 diabetes mellitus during the perioperative period of cardiac surgery in the ward and also might be useful for decreasing the frequency of arterial blood collection in the intensive care unit.

Efficacy of Dietitian-instructed Low Iodine Diet for Radioiodine Remnant Tissue Ablation for Thyroid Cancer.

We evaluated the significance of dietary instruction (DI) for patients who are going on a low iodine diet (LID) as a preparation for remnant tissue ablation for thyroid cancer. DI was done by a dietarian using a dedicated handbook we have developed. To assess the effect of LID on depleting body iodine, urinary iodine concentration (UIC) in patients with post-surgical papillary thyroid cancer was measured twice, before and after LID. UIC on the day of radioiodine administration was compared with radioiodine uptake (RU) in the remnant tissue. Additionally, the association between clinical and lifestyle-related features of patients and the outcome of LID were investigated. A questionnaire survey was conducted to determine whether the DI helped patients go on LID. The mean value of UIC after the one-week LID was decreased to about 15% of the baseline value. There was a significant inverse correlation between UIC and RU (r= -0.694). Age and UIC before the start of LID were linked to successful outcome of LID. In the questionnaire survey, 84% of the participants answered that the handbook helped them go on a LID. Likewise, 80% answered that they could manage their LID without using the boil-in-the-bag low iodine food. LID successfully decreased UIC in patients undergoing remnant tissue ablation. DI by a dietitian may make a practice of LID easier.