Evaluation of the factors related to difficult ultrasound-guided radial artery catheterization in small children: A prospective observational study.

BACKGROUND: Although ultrasound guidance has significantly improved the success rate of radial artery catheterization, the failure rate in children is still high. For the further improvement of success rate, we prospectively evaluated the factors that make ultrasound-guided radial artery catheterization difficult in children under two years old. METHODS: From October 2018 to September 2019, patients who required radial artery catheterization for surgery were enrolled. After collecting the anatomical characteristics of the radial artery using ultrasound at the puncture site, ultrasound-guided radial artery catheterization was performed by one experienced anaesthesiologist. The primary outcome was to identify the factors related to the first attempt failure. The factors associated with the total duration of the procedure until success were also evaluated. RESULTS: A total of 183 children were included in the analysis. A radial artery cross-sectional area of ≤1 mm2 (odds ratio [OR] = 5.26; 95% confidence interval [CI], 2.48-11.18; P < .0001) and the presence of an anomalous radial artery branch (OR = 3.37; 95% CI, 1.43-7.95; P = .005) were independent predictors of first-attempt failure during ultrasound-guided radial artery catheterization. The total procedure time was also negatively associated with the small cross-sectional area (P < .001). CONCLUSIONS: A cross-sectional area of ≤ 1 mm2 and the presence of an anomalous branch of radial artery significantly increased the difficulty of ultrasound-guided radial artery catheterization in children under two years old. In patients of these ages, pre-procedural ultrasound scanning to find an optimal site for catheterization may increase the first-attempt success rate although further studies are needed to verify our results. TRIAL REGISTRATION: Clinical Research Information Service (https://crits.nih.go.kr, October 6, 2018 [KCT0003239]; Principle investigator: Jong-Hwan Lee).

Enhancement of the optical properties of CsPbBr3 perovskite nanocrystals using three different solvents.

Green-emitting CsPbBr3 perovskite nanocrystals were synthesized by the modified hot-injection method using three different solvents. The produced nanocrystals showed a narrow green emission band centered at 515-520 nm with full width at half-maximum (FWHM) values of approximately 18-20 nm. The highest photoluminescence quantum yield (PLQY) was obtained for the nanocrystal sample synthesized using a paraffin liquid solvent, with a value of 70.1% under excitation at 450 nm. The CsPbBr3 nanocrystals film light-emitting diodes (LED) chip module showed a luminous efficacy of 40.7lm/Wrad. The white LED (WLED) with green CsPbBr3 and red CsPbI3 nanocrystal films emitted bluish-white light with a high color rendering index of 89, and the luminous efficacy of the WLED reached 16.3lm/Wrad.

Leukotrienes induce the migration of Th17 cells.

Th17 cell trafficking in response to leukotriene signaling is poorly understood. Here we showed that Th17 cells express high levels of leukotriene B4 receptor 1 (LTB4R1) and cysteinyl leukotriene receptor 1 (CysLTR1). Th17 cells migrated under the guidance of leukotriene B4 and D4. The migration of Th17 cells was more efficient than that of Th1 and Th2 cells, and it was blocked by specific inhibitors of LTB4R1 or CysLTR1. Studies in an animal model of experimental autoimmune encephalomyelitis revealed that treatment with montelukast alleviated disease symptoms and inhibited the recruitment of Th17 cells to the central nervous system. Thus, leukotrienes may act as chemoattractants for Th17 cells.

Corrigendum to "Breast mucocele-like lesions (MLL): a case report and review of the literature". [Radiol Case Rep 2024;19:1083-1089].

[This corrects the article DOI: 10.1016/j.radcr.2023.12.017.].

Breast Mucocele-like lesions (MLL): A case report and review of the literature.

Mucocele-like lesions of the breast are rare, usually presenting themselves as suspicious findings on imaging, warranting biopsies. It can be associated with several degrees of hyperplasia, including atypical ductal hyperplasia and ductal carcinoma in situ, historically being considered a high-risk lesion. It also can be an underestimated invasive carcinoma in a percutaneous biopsy. When facing a histologic diagnosis of a mucocele-lesion in a percutaneous biopsy, it is important to be aware of these lesions' significance to make the most appropriate interpretation, recommendation, and management. The purpose of this work is to present some cases of breast mucocele-like lesions from our Institution and perform a review of the literature.

Breast granular cell tumor: A case report and review of literature.

Granular cell tumor (GCT) is a rare neoplasm. Its diagnosis is based on imaging and pathological findings. There are only a few reported cases of GCT of the breast (GCTB) in the literature. We present a case of a female patient diagnosed with GCTB and perform a review on the prevalence, diagnosis, histology, treatment, and prognosis.

Enhancing microbial CO2 electrocatalysis for multicarbon reduction in a wet amine-based catholyte.

Microbial CO2 electroreduction (mCO2ER) offers a promising approach for producing high-value multicarbon reductants from CO2 by combining CO2 fixing microorganisms with conducting materials (i. e., cathodes). However, the solubility and availability of CO2 in an aqueous electrolyte pose significant limitations in this system. This study demonstrates the efficient production of long-chain multicarbon reductants, specifically carotenoids (~C40), within a wet amine-based catholyte medium during mCO2ER. Optimizing the concentration of the biocompatible CO2 absorbent, monoethanolamine (MEA), led to enhanced CO2 fixation in the electroautotroph bacteria. Molecular biological analyses revealed that MEA in the catholyte medium redirected the carbon flux towards carotenoid biosynthesis during mCO2ER. The faradaic efficiency of mCO2ER with MEA for carotenoid production was 4.5-fold higher than that of the control condition. These results suggest the mass transport bottleneck in bioelectrochemical systems could be effectively addressed by MEA-assissted mCO2ER, enabling highly efficient production of valuable products from CO2.

Alkali Cation Engineered Chemical Self-Oxidation of Copper Oxide Nanowire-Based Photocathodes.

Hydrogen energy production through photoelectrochemical (PEC) water splitting has great potential in the field of renewable energy. This study focuses on the hydration enthalpy difference of cations (Li+ , Na+ , and K+ ) in an aqueous solution for the chemical self-oxidation process without an external applied bias. The thickness of the cation/H2 O double layer is controlled. The starting materials are low-cost copper foil and the synthesis uses alkali cation-engineered chemical self-oxidation. Li+ ions are strongly attracted to water molecules. This forms a sufficient OH- layer on the Cu foil surface. By accelerating the oxidation reaction, a large surface area of Cu(OH)x nanowires (NWs) with high purity and a uniform shape are obtained. This optimal p-type Cu2 O NWs photocathode is CuO-free, has the highest conductivity, and is fabricated through phase transition using precise vacuum annealing. The other alkali cations produce the Cu2 O/CuO mixed or CuO phases that degrade the PEC performances with severe corrosive reactions. The Cu/Li : Cu2 O/AZO/TiO2 /Pt photocathode has a 50 h stability with a photocurrent density of 8.4 mA cm-2 at 0 VRHE . The fabricated photoelectrode did not structurally collapse after stability measurements during this period. The captured hydrogen production was in agreement with the calculated faradaic efficiency.

Variations in dose distribution and optical properties of Gafchromic(TM) EBT2 film according to scanning mode.

PURPOSE: The authors aim was to investigate the effects of using transmission and reflection scanning modes, the film orientation during scanning, and ambient room light on a dosimetry system based on the Gafchromic(TM) EBT2 film model. METHODS: For calibration, the films were cut to 3 × 3 cm(2) and irradiated from 20 to 700 cGy at the depth of maximum dose using 6 and 10 MV photon beams in a 10 × 10 cm(2) field size. Absolute dose calibration of the linear accelerator was done according to the TRS398 protocol. An FG65-G ionization chamber was used to monitor the dose while irradiating the films in solid water. The film pieces were scanned with an EPSON Expression 1680 Pro flatbed scanner in transmission and reflection modes. Authors investigated the effect of orientation on films and examined the optical properties of EBT2 film using an ellipsometer and an ultraviolet (UV)/visible spectrometer to explain the dosimetric dependence of the film on orientation during the scanning process. To investigate the effect of ambient room light, films were preirradiated in 6 and 10 MV photon beams with intensity-modulated radiotherapy (IMRT) quality assurance (QA) plans, and then exposed to room light, either directly for 2 days in a workroom or for 2 months in a film box. Gamma index pass criteria of (3%, 3 mm) were used. RESULTS: The dose response curves based on net optical density (NOD) indicated that the reflection scanning mode can provide a better dose sensitivity than the transmission scanning mode, whereas the standard deviation of the dose is greater in reflection mode than in transmission mode. When the film was rotated 90° from the portrait orientation, the average dose of the EBT2 film decreased by 11.5-19.6% in transmission mode and by 1.5-2.3% in reflection mode. Using an ellipsometer, variation of the refractive index of EBT2 film-the birefringence property-was found to be the largest between 45° (1.72 and 1.71) and 135° (1.8 and 1.77) for 300 and 800 cGy. Absorption spectra of EBT2 films measured with spectrometer were the function of film orientation. The readings in reflection scanning mode were more stable against room light than those in transmission scanning mode, although dose readings increased in both modes after the films were exposed to room light. CONCLUSIONS: The transmission scanning mode exhibited a strong dependence on film orientation during scanning and a change in optical density resulting from room light exposure, so a constant scanning orientation and minimal exposure to light can reduce uncertainty in the measured dose (23 ± 3%). The angular dependence was analyzed using Jones matrices and optical properties of EBT2 film were obtained using an ellipsometer and an UV/visible spectrometer. The reflection scanning mode has relatively good stability with respect to room light and film orientation on a scanner, although the large standard deviation of dose is a disadvantage in measurements of absolute dose. Reflection scanning mode can offer a potential advantage for film dosimetry in radiotherapy, although transmission scanning mode is still recommended for dosimetry as it provides better uncertainty results.

Facile nanostructured zinc oxide coating technique for antibacterial and antifouling air filters with low pressure drop.

Air filters effectively filtrate external contaminants including pathogenic bioaerosols; however, they also act as culture sites for the pathogenic bacteria captured in nutrient organic pollutants. Although many researchers have applied various antibacterial coatings to filters, the coating application inevitably increased the pressure drop, leading to the low efficiency and high energy consumption of the purification system. Herein, we report a simple nanostructured zinc oxide (ZnO) coating technique to confer a polypropylene nonwoven filter with superior antibacterial, antifouling and anti-biofilm properties without an additional pressure drop. For aerodynamic coating designs, filters were directly immersed into low concentration precursor solutions to enable the sedimentation of the ZnO sol-gel particles on the filter fibers according to fluid dynamic. The precursor concentration affected the surface topology and so properties of the as-fabricated coating. 0.07 M precursor solution produced a rose-like nanostructured coating exhibiting no pressure-drop increase. The large specific surface area and hydrophobic surface killed and then repelled the attached bacteria effectively. As a result, the bare filter promoted the growth and consequent biofilm formation of the surface bacteria in a favorable environment for the growth of microorganisms, while the coated filter successfully suppressed biofilm development.

De novo dual functional 3D scaffold using computational simulation with controlled drug release.

A novel and facile synthesis is made of cotton-like three-dimensional (3D) fibrous scaffold containing spatiotemporally defined patterns of simvastatin (SIM) optimized for angiogenesis-coupled osteogenesis. Herein, we demonstrate the 3D fiber deposition mechanism in detail during the electrospinning process via computer simulation. The 3D fibrous scaffolds were functionalized with hydroxyapatite nanoparticles (HA - NPs) to induce the biomineralization process mimicking the natural apatite layer. The morphology, physiochemical properties, biomimetic mineralization, and drug release of the as-fabricated 3D fibrous scaffolds of simvastatin-loaded poly (ɛ-caprolactone) poly (glycerol-sebacate) hydroxyapatite nanoparticles (3D - PGHS) were investigated. The effects of simvastatin on the osteogenic differentiation of human mesenchymal stem cells (hMSCs) and angiogenesis in human umbilical vein endothelial cells (HUVECs) were assessed. The results showed that the 3D - PGHS both enhanced the expression of osteogenic markers including ALP, RUNX2, and COLA1 in hMSCs, and promoted the migration and tube formation of HUVECs. This finding demonstrates the potential of 3D scaffold-loaded SIM as a putative point-of-care therapy for tightly controlled tissue regeneration.

Completion thyroidectomy may not be required for papillary thyroid carcinoma with multifocality, lymphovascular invasion, extrathyroidal extension to the strap muscles, or five or more central lymph node micrometastasis.

OBJECTIVE: This study aimed to determine whether completion thyroidectomy is necessary based on long-term follow-up oncological results according to various clinical and pathological characteristics of patients with papillary thyroid carcinoma (PTC) who underwent lobectomy. MATERIALS AND METHODS: We enrolled 1815 patients with PTC who underwent thyroid lobectomy from January 2003 to December 2014. Various clinical and pathological characteristics were reviewed retrospectively, and clinicopathologic characteristics and recurrence rates were analyzed. RESULTS: Eighty-two (4.5%) patients showed locoregional recurrence during the average 10.2-year follow-up period. There was no significant difference in tumor size, multifocality, lymphovascular invasion (LVI), microscopic or strap muscle-extrathyroidal extension, and central neck lymph node (LN) micrometastasis between the recurrence and non-recurrence groups. The gross strap muscle-extrathyroidal extension group was associated with older age (p < 0.001), larger tumor size (p < 0.001), more capsular invasion (p < 0.001), and more LVI (p < 0.001) than the negative extrathyroidal extension group; there was no significant difference in recurrence between the groups (p = 0.096). Patients with five or more central LN micrometastases were associated with younger age (p = 0.006), larger tumor size (p = 0.04), and presence of LVI (p = 0.033) than patients with less than five central LN metastases; there was no significant difference in recurrence between the groups (p = 0.867). All patients with recurrence were cured through reoperation after recurrence was confirmed. CONCLUSION: After thyroid lobectomy, PTC patients with multifocality, LVI, extrathyroidal extension to the strap muscles, or five or more central LN micrometastases may not require immediate completion thyroidectomy.

Natural Phytochemicals as Novel Therapeutic Strategies to Prevent and Treat Parkinson's Disease: Current Knowledge and Future Perspectives.

Parkinson's disease (PD) is the second-most common neurodegenerative chronic disease affecting both cognitive performance and motor functions in aged people. Yet despite the prevalence of this disease, the current therapeutic options for the management of PD can only alleviate motor symptoms. Research has explored novel substances for naturally derived antioxidant phytochemicals with potential therapeutic benefits for PD patients through their neuroprotective mechanism, targeting oxidative stress, neuroinflammation, abnormal protein accumulation, mitochondrial dysfunction, endoplasmic reticulum stress, neurotrophic factor deficit, and apoptosis. The aim of the present study is to perform a comprehensive evaluation of naturally derived antioxidant phytochemicals with neuroprotective or therapeutic activities in PD, focusing on their neuropharmacological mechanisms, including modulation of antioxidant and anti-inflammatory activity, growth factor induction, neurotransmitter activity, direct regulation of mitochondrial apoptotic machinery, prevention of protein aggregation via modulation of protein folding, modification of cell signaling pathways, enhanced systemic immunity, autophagy, and proteasome activity. In addition, we provide data showing the relationship between nuclear factor E2-related factor 2 (Nrf2) and PD is supported by studies demonstrating that antiparkinsonian phytochemicals can activate the Nrf2/antioxidant response element (ARE) signaling pathway and Nrf2-dependent protein expression, preventing cellular oxidative damage and PD. Furthermore, we explore several experimental models that evaluated the potential neuroprotective efficacy of antioxidant phytochemical derivatives for their inhibitory effects on oxidative stress and neuroinflammation in the brain. Finally, we highlight recent developments in the nanodelivery of antioxidant phytochemicals and its neuroprotective application against pathological conditions associated with oxidative stress. In conclusion, naturally derived antioxidant phytochemicals can be considered as future pharmaceutical drug candidates to potentially alleviate symptoms or slow the progression of PD. However, further well-designed clinical studies are required to evaluate the protective and therapeutic benefits of phytochemicals as promising drugs in the management of PD.

SOX9 is required for kidney fibrosis and activates NAV3 to drive renal myofibroblast function.

Renal fibrosis is a common end point for kidney injury and many chronic kidney diseases. Fibrogenesis depends on the sustained activation of myofibroblasts, which deposit the extracellular matrix that causes progressive scarring and organ failure. Here, we showed that the transcription factor SOX9 was associated with kidney fibrosis in humans and required for experimentally induced kidney fibrosis in mice. From genome-wide analysis, we identified Neuron navigator 3 (NAV3) as acting downstream of SOX9 in kidney fibrosis. NAV3 increased in abundance and colocalized with SOX9 after renal injury in mice, and both SOX9 and NAV3 were present in diseased human kidneys. In an in vitro model of renal pericyte transdifferentiation into myofibroblasts, we demonstrated that NAV3 was required for multiple aspects of fibrogenesis, including actin polymerization linked to cell migration and sustained activation of the mechanosensitive transcription factor YAP1. In summary, our work identifies a SOX9-NAV3-YAP1 axis involved in the progression of kidney fibrosis and points to NAV3 as a potential target for pharmacological intervention.

A comprehensive overview and recent advances on polyhydroxyalkanoates (PHA) production using various organic waste streams.

Polyhydroxyalkanoates (PHA) are appealing as an important alternative to replace synthetic plastics owing to its comparable physicochemical properties to that of synthetic plastics, and biodegradable and biocompatible nature. This review gives an inclusive overview of the current research activities dealing with PHA production by utilizing different waste fluxes generated from food, milk and sugar processing industries. Valorization of these waste fluxes makes the process cost effective and practically applicable. Recent advances in the approaches adopted for waste treatment, fermentation strategies, and genetic engineering can give insights to the researchers for future direction of waste to bioplastics production. Lastly, synthesis and application of PHA-nanocomposites, research and development challenges, future perspectives for sustainable and cost-effective PHB production are also discussed. In addition, the review addresses the useful information about the opportunities and confines associated with the sustainable PHA production using different waste streams and their evaluation for commercial implementation within a biorefinery.

Dendropanax Morbiferus and Other Species from the Genus Dendropanax: Therapeutic Potential of Its Traditional Uses, Phytochemistry, and Pharmacology.

The Dendropanax genus is a kind of flowering plant in the family of Araliaceae that encompasses approximately 91 to 95 species. Several Dendropanax species are used as traditional medicinal plants, extensively used Korea and South America and other parts of the world. Almost every part of the plant, including the leaves, bark, roots, and stems, can be used as traditional medicine for the prevention and management of a broad spectrum of health disorders. This paper sought to summarizes the ethnopharmacological benefits, biological activities, and phytochemical investigations of plants from the genus Dendropanax, and perhaps to subsequently elucidate potential new perspectives for future pharmacological research to consider. Modern scientific literature suggests that plants of the Dendropanax genus, together with active compounds isolated from it, possess a wide range of therapeutic and pharmacological applications, including antifungal, anti-complement, antioxidant, antibacterial, insect antifeedant, cytotoxic, anti-inflammatory, neuroprotective, anti-diabetic, anti-cancer, and anti-hypouricemic properties. The botanical descriptions of approximately six to 10 species are provided by different scientific web sources. However, only six species, namely, D. morbiferus, D. gonatopodus, D. dentiger, D. capillaris, D. chevalieri, and D. arboreus, were included in the present investigation to undergo phytochemical evaluation, due to the unavailability of data for the remaining species. Among these plant species, a high concentration of variable bioactive ingredients was identified. In particular, D. morbifera is a traditional medicinal plant used for the multiple treatment purposes and management of several human diseases or health conditions. Previous experimental evidence supports that the D. morbifera species could be used to treat various inflammatory disorders, diarrhea, diabetes, cancer, and some microbial infections. It has recently been reported, by our group and other researchers, that D. morbifera possesses a neuroprotective and memory-enhancing agent. A total of 259 compounds have been identified among six species, with 78 sourced from five of these species reported to be bioactive. However, there is no up-to-date information concerning the D. morbifera, its different biological properties, or its prospective benefits in the enhancement of human health. In the present study, we set out to conduct a comprehensive analysis of the botany, traditional medicinal history, and medicinal resources of species of the Dendropanax genus. In addition, we explore several phytochemical constituents identified in different species of the Dendropanax genus and their biological properties. Finally, we offer comprehensive analysis findings of the phytochemistry, medicinal uses, pharmacological actions, and a toxicity and safety evaluation of the D. morbifera species and its main bioactive ingredients for future consideration.

Medicinal Profile, Phytochemistry, and Pharmacological Activities of Murraya koenigii and its Primary Bioactive Compounds.

The discovery of several revitalizing molecules that can stop or reduce the pathology of a wide range of diseases will be considered a major breakthrough of the present time. Available synthetic compounds may provoke side effects and health issues, which heightens the need for molecules from plants and other natural resources under discovery as potential methods of replacing synthetic compounds. In traditional medicinal therapies, several plant extracts and phytochemicals have been reported to impart remedial effects as better alternatives. Murraya koenigii (M. koenigii) belongs to the Rutaceae family, which is commonly used as a medicinally important herb of Indian origin in the Ayurvedic system of medicine. Previous reports have demonstrated that the leaves, roots, and bark of this plant are rich sources of carbazole alkaloids, which produce potent biological activities and pharmacological effects. These include antioxidant, antidiabetic, anti-inflammatory, antitumor, and neuroprotective activities. The present review provides insight into the major components of M. koenigii and their pharmacological activities against different pathological conditions. The review also emphasizes the need for more research on the molecular basis of such activity in various cellular and animal models to validate the efficacy of M. koenigii and its derivatives as potent therapeutic agents.

The Investigation of Hyaluronic Acid (The Chaeum Premium No.2®) to Evaluate the Efficacy and Safety for Injection Laryngoplasty in Unilateral Vocal Cord Paralysis: A Single Center, Phase II Trial

Background and Objectives@#This study aimed to evaluate the clinical efficacy and safety of hyaluronic acid (HA) (The Chaeum Premium No.2®) for injection laryngoplasty (IL) in unilateral vocal cord paralysis (UVCP) patients.Materials and Method This clinical trial has been registered with the clinical research information service of the Republic of Korea (No. KCT0007597). Ten patients with UVCP were enrolled. Auditory-perceptual evaluation, acoustic analysis, aerodynamic analysis, electroglottography, laryngoscopy, and voice handicap index (VHI)-30 were assessed before injection, at 1, 3, and 6 months after injection. @*Results@#All auditory-perceptual parameters gradually showed statistically significant improvements at 1, 3, and 6 months after injection. Acoustic, aerodynamic parameters, electroglottography, and VHI-30 showed gradual improvements at 1 and 3 months after injection. Then, they showed slight deterioration 6 months after injection. There were no adverse effects in all patients. @*Conclusion@#IL using HA is an effective and safe treatment for UVCP patients.

Pancreatoduodenectomy with colon-last approach for advanced pancreatic head cancer

Purpose@#Margin-negative surgery is very important in surgical oncology. Considering margin-negative pancreatectomy is known to be essential for cure of the pancreatic cancer, pancreatoduodenectomy with combined venous vascular or arterial resection can be a potential option for margin-negative resection, especially, in era of neoadjuvant treatment with potent systemic chemotherapy. To the contrary, special attention was not paid on combined colonic resection during PD. In this article, safe surgical technique for PD with combined colonic resection is introduced, under the name of PD with “colon-last” approach. @*Methods@#At Severance Hospital (Yonsei University College of Medicine, Seoul, Republic of Korea), between 2014 and 2021, a total of six patients underwent PD with “colon-last” approach. The surgical technique and surgical outcome are reviewed. @*Results@#All patients recovered without major complications (Clavien-Dindo classification grade ≥ III) after surgery, and most of them recovered after conservative treatment with postoperative pancreatic fistula biochemical leak. None of the patients were readmitted. Only the first and second cases represent cancer-related mortality, and the other patients are still alive and are being followed up. @*Conclusion@#It is hoped that the present technique, PD with colon-last approach, could be helpful enhance the procedural safety in treating advanced cancer requiring PD with combined colon resection. However, its technical safety and oncologic role should be validated by many pancreatic surgeons’ collaborative studies in the near future.

Risk of Subsequent Primary Cancers in Thyroid Cancer Survivors according to the Dose of Levothyroxine: A Nationwide Cohort Study

Background@#Current research has not investigated the effect of thyroid-stimulating hormone suppression therapy with levothyroxine on the risk for developing subsequent primary cancers (SPCs). This study aimed to investigate the association between levothyroxine dosage and the risk for SPCs in thyroid cancer patients. @*Methods@#We conducted a nationwide population-based retrospective cohort study form Korean National Health Insurance database. This cohort included 342,920 thyroid cancer patients between 2004 and 2018. Patients were divided into the non-levothyroxine and the levothyroxine groups, the latter consisting of four dosage subgroups according to quartiles. Cox proportional hazard models were performed to evaluate the risk for SPCs by adjusting for variables including cumulative doses of radioactive iodine (RAI) therapy. @*Results@#A total of 17,410 SPC cases were observed over a median 7.3 years of follow-up. The high-dose levothyroxine subgroups (Q3 and Q4) had a higher risk for SPC (adjusted hazard ratio [HR], 1.14 and 1.27; 95% confidence interval [CI], 1.05–1.24 and 1.17– 1.37; respectively) compared to the non-levothyroxine group. In particular, the adjusted HR of stomach (1.31), colorectal (1.60), liver and biliary tract (1.95), and pancreatic (2.48) cancers were increased in the Q4 subgroup. We consistently observed a positive association between high levothyroxine dosage per body weight and risk of SPCs, even after adjusting for various confounding variables. Moreover, similar results were identified in the stratified analyses according to thyroidectomy type and RAI therapy, as well as in a subgroup analysis of patients with good adherence. @*Conclusion@#High-dose levothyroxine use was associated with increased risk of SPCs among thyroid cancer patients regardless of RAI therapy.