The increasing of intracellular calcium concentration is a fundamental process for mediating osteoclastogenesis, which is involved in osteoclastic bone resorption. Cytosolic calcium binds to calmodulin and subsequently activates calcineurin, leading to NFATc1 activation, a master transcription factor required for osteoclast differentiation. Targeting the various activation processes in osteoclastogenesis provides various therapeutic strategies for bone loss. Diverse compounds that modulate calcium signaling have been applied to regulate osteoclast differentiation and, subsequently, attenuate bone loss. Thus, in this review, we summarized the modulation of the NFATc1 pathway through various compounds that regulate calcium signaling and the calcium influx machinery. Furthermore, we addressed the involvement of transient receptor potential channels in osteoclastogenesis.

Fibroblast-like synoviocytes (FLSs) and osteoclasts are central cells in the maintenance of joint homeostasis. Rheumatoid arthritis (RA) is a chronic inflammatory disease of joints that induces cytokine-activated FLSs and progressive bone erosion. Interactions between FLSs and other cells, such as T cells and B cells, have been recognized in the development of RA. Here we hypothesized that calcium released from bone by mature osteoclasts might activate FLSs, which are also affected by inflammatory cytokines in the inflamed synovium. Osteoclastogenesis occurs in the presence of cytokine-stimulated FLS medium, and calcium released from the bone disc activates FLS migration. We first investigated the calcium and cytokine feedback loop between FLSs and osteoclast maturation. Moreover, by addressing the role of the sodium-bicarbonate cotransporter NBCn1 in osteoclastogenesis, we found that the inhibition of NBCn1 attenuated the infinite calcium and cytokine feedback loop between FLSs and osteoclasts. In a collagen-induced arthritis mouse model, the inhibition of NBC reduced the RA pathological phenotype and bone resorption area in the femur. These results suggest that modulation of the crosstalk between FLSs and osteoclasts by inhibiting the calcium and cytokine feedback loop could be considered to develop pioneering strategies to combat RA severity and dysregulated bone homeostasis.

Objectives: The demand for dental care is expected to increase as the population ages. This study aimed to predict the utilization of dental implant care following the expansion of national health insurance benefits for dental implants. Methods: Multiple linear regression analysis was performed on HIRA big data open portal data and DNN-based artificial intelligence models to forecast the utilization of dental care in relation to the national health insurance coverage for dental implants. Results: National health insurance coverage of dental implants was found to be associated with the number of patients using dental implant services and demonstrated a statistical significance. The dental implant services utilization increased with the increased dental implant health insurance benefits for the elderly population, increased mean by region, increased number of dental institutions by region, and increased health insurance coverage rate for dental implants. However, the dental implant services utilization decreased with the increased number of older people living alone and increased size of dental institutions. Conclusions: With the expansion of the national health insurance coverage for dental implants, it is predicted that the utilization of dental implant medical services will increase in the future.

우리나라의 인구 고령화는 급격히 진행되고 있다. 이는 수도권보다 지방에서 더욱 집중적으로 일어나고 있는 현상으로 지방도시의 소멸의 위기까지 거론되고 있다. 구직활동을 위해 도시로 이주하는 청년계층 외에 노인계층 또한 도시 여러 서비스를 제공 받고자 도시로 이주하려는 경향을 보이고 있다. 여러 가지 도시 서비스중 의료시설에 대한 선호로 인해 노인인구의 이동이 발생하는 것을 고려하여 본 연구에서는 회귀분석과 머신러닝 기법을 활용하여 전국을 대상으로 의료시설의 접근성이 노인 인구 증가에 미치는 영향을 연구 하였다. 분석 결과, 회귀분석의 수정된 결정계수는 0.507이었으며, 머신러닝 분석 결과 MAPE값은 최소값 기준 27.5%의 성능을 보였다. 본 연구의 결과를 통해 지방 도시에 노인들의 수요를 고려한 의료 서비스 공급의 당위성을 확보하고, 지방 도시에 노인들의 수요를 고려한 의료 서비스를 제공함으로써 노인들의 삶의 질을 높이고 지방도시의 소멸에 대비하여 국토의 균형발전을 도모할 수 있을 것이다.

Hye Young Mun, Septika Prismasari, Jeong Hee Hong, Hana Lee, Doyong Kim, Han Sung Kim, Dong Min Shin, and Jung Yun Kang. Korean J Physiol Pharmacol 2025;29:9-19. https://doi.org/10.4196/kjpp.24.115

Objective: Dental instruments are often designed for single use; however, some dental clinics resort to reusing instruments, including saliva ejectors. In this study, we aimed to investigate and compare various disinfection and sterilization methods for contaminated disposable salivary ejectors. Methods: Saliva ejectors contaminated with Streptococcus mutans were divided into f ive groups: negative control, positive control, cleaning, disinfection, and sterilization. Surface contamination and microbial culture tests were conducted using the adenosine triphosphate (ATP) test and colony-forming units (CFUs) counting, respectively. One-way ANOVA was used to assess the differences among groups. Results: There were no significant differences among the cleaning, disinfection, and sterilization groups based on immediate ATP test. However, CFU counts were significantly higher in the cleaning and disinfection groups compared to negative control group, while no microbial growth was observed in the sterilization group. Conclusions: This study demonstrated that saliva ejectors harbor bacteria capable of growth, even after cleaning with a toothbrush or disinfectant. Autoclaving proved to be the most effective sterilization method, eliminating microbial growth, and allowing for microbiological reuse. Future studies involving diverse microorganisms and different types of contaminants are recommended.