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Fine particulate matter (FPM) is a major component of air pollution and has emerged as a significant global health concern owing to its adverse health effects. Previous studies have investigated the correlation between bone health and FPM through cohort or review studies. However, the effects of FPM exposure on bone health are poorly understood. This study aimed to investigate the effects of FPM on bone health and elucidate these effects in vitro and in vivo using mice. Micro-CT analysis in vivo revealed FPM exposure decreased bone mineral density, trabecular bone volume/total volume ratio, and trabecular number in the femurs of mice, while increasing trabecular separation. Histological analysis showed that the FPM-treated group had a reduced trabecular area and an increased number of osteoclasts in the bone tissue. Moreover, in vitro studies revealed that low concentrations of FPM significantly enhanced osteoclast differentiation. These findings further support the notion that short-term FPM exposure negatively impacts bone health, providing a foundation for further research on this topic. [ABSTRACT FROM AUTHOR]

Diatoms are photosynthetic unicellular organisms surrounded by silica-based cell walls known as frustules. Given their widespread distribution in aquatic systems and their prolific nature, diatoms play a pivotal role in global silica cycling. Silicon transporter (SIT) proteins play a critical role in this process by facilitating the import and intracellular transport of dissolved silica. Therefore, it is important to understand the mechanisms controlling the uptake and utilization of silica below the concentration range of Si, where free diffusion of Si is insufficient for proliferation. In our investigation, we observed varied frustule synthesis responses of Thalassiosira eccentrica LIMS-PS-3165 under different nutrient limitations through fluorescence labeling of newly synthesized frustules. Additionally, we examined the expression patterns of SIT genes following silicon replenishment and analyzed the sequences of two SITs, TeSIT1/2 and TeSIT3, from T. eccentrica. Upon silicon resupply after a period of silicon deprivation, TeSIT1/2 transcription was downregulated, whereas TeSIT3 expression remained unaffected. Analysis of the predicted amino acid sequences revealed that TeSIT1/2 and TeSIT3 share 10 transmembrane domains and two conserved GXQ motifs, indicating structural similarities and differences in their silicon transport mechanisms. These findings enhance our understanding of silicon transport responses in T. eccentrica under nutrient-limited conditions and contribute to broader knowledge of silica biogeochemistry in diatoms. [ABSTRACT FROM AUTHOR]

Purpose: Cardiac radioablation is a novel, non-invasive treatment for ventricular tachycardia (VT), involving a single fractional stereotactic ablative body radiotherapy (SABR) session with a prescribed dose of 25 Gy. This complex procedure requires a detailed workflow and stringent dose constraints compared to conventional radiation therapy. This study aims to establish a consistent institutional workflow for single-fraction cardiac VT-SABR, emphasizing robust plan evaluation and quality assurance. Materials and Methods: The study developed a consistent institutional workflow for VT-SABR, including computed tomography (CT) simulation, target volume definition, treatment planning, robust plan evaluation, quality assurance, and image-guided strategy. The workflow was implemented for two patients with cardiac arrhythmia. Accurate target volume definition using planning CT images and electronic anatomical mapping was critical. A four-dimensional (4D) cone-beam CT (CBCT) and breath-hold electrocardiographic gated CT images reliably detected target motion. Results: The resulting plans exhibited a conformity index greater than 0.7 and a gradient index around G4.0. Dose constraints for the planning target volume (PTV) aimed for 95% or higher PTV dose coverage, with a maximum dose of 200% or lower. However, one case did not meet the PTV dose coverage due to the proximity of the PTV to gastrointestinal organs. Plans adhered to dose constraints for organs at risk near the heart, but meeting constraints for specific cardiac sub-structures was challenging and dependent on PTV location. Conclusion: The plans demonstrated robustness against respiratory motion and patient positional uncertainty through a robust evaluation function. The 4D and intra-fractional CBCT were effective in verifying target motion and setup stability. [ABSTRACT FROM AUTHOR]

Purpose: This report offers a detailed examination of the inception and current state of the Heavyion Therapy Center (HITC) at the Yonsei Cancer Center (YCC), setting it apart as the world's first center equipped with a fixed beam and two superconducting gantries for carbon-ion radiation therapy (CIRT). Materials and Methods: Preparations for CIRT at YCC began in 2013; accordingly, this center has completed a decade of meticulous planning and culminating since the operational commencement of the HITC in April 2023. Results: This report elaborates on the clinical preparation for adopting CIRT in Korea. It includes an extensive description of HITC's facility layout at YCC, which comprises the accelerator and treatment rooms. Furthermore, this report delineates the clinical workflow, criteria for CIRT application, and the rigorous quality assurance processes implemented at YCC. It highlights YCC's sophisticated radiation therapy infrastructure, collaborative initiatives, and the efficacious treatment of >200 prostate cancer cases utilizing CIRT. Conclusion: This manuscript concludes by discussing the prospective influence of CIRT on the medical domain within Korea, spotlighting YCC's pioneering contribution and forecasting the widespread integration of this groundbreaking technology. [ABSTRACT FROM AUTHOR]

PURPOSE. This pilot study investigated the effect of surface roughness on osseointegration by comparing two types of commercial SLA-treated dental implants with different surface roughness levels: moderately rough (Sa = 1 - 2 µm) and rough surfaces (Sa > 2 µm). MATERIALS AND METHODS. Two implant groups were studied: TS (rough surface) and ADD (moderately rough surface) groups. Surface characteristics were analyzed using optical profilometry and SEM. In vitro studies using BRITER cells assessed cell adhesion, proliferation, and osteogenic differentiation through CCK-8 assay and qRT-PCR for osteopontin (OPN), osteocalcin (OCN), and alkaline phosphatase (ALP) expression. The in vivo study involved 12 implants (six per group) placed in mandibular defects of two beagle dogs. After 8 weeks, histomorphometric analysis evaluated bone to implant contact (BIC) and inter-thread bone density (ITBD). Statistical analysis used Student's t-test and two-way ANOVA for in vitro data, and Mann-Whitney U test for in vivo data. RESULTS. Surface analysis revealed Sa values of 2.50 ± 0.27 µm for the TS group and 1.80 ± 0.06 µm for the ADD group. In vitro studies showed no significant differences in cell adhesion and proliferation between the groups (P > .05). However, gene expression patterns differed, with ADD group showing higher OPN expression (P < .001) and TS group showing higher ALP expression (P < .01). The in vivo study revealed no statistically significant differences in BIC and ITBD between the two groups (P > .05). CONCLUSION. Surface roughness influenced osteoblast differentiation in vitro, but did not significantly affect osseointegration outcomes in vivo. Both moderately rough and rough surfaces appeared to support comparable levels of osseointegration. Larger studies are needed to confirm these findings and determine optimal implant surface characteristics. [ABSTRACT FROM AUTHOR]