Purpose: The Dietary Reference Intakes for Koreans (KDRIs) serve as a foundation for nutrition policy, nutrition education, and dietary intake evaluation among healthy Koreans.The KDRIs are revised every five years to ensure that the guidelines are based on a robust and up-to-date scientific foundation. For the 2025 KDRIs for calcium, the 2020 KDRIs were revisited, and references were critically evaluated. Methods: All references cited in the 2020 KDRIs were extracted, reviewed, and organized according to the framework for the estimated average requirement (EAR). Each reference was evaluated based on the participant characteristics, including age, race/ethnicity, and health status, as well as study design, exposure, and outcomes. In addition, calculations for the EAR and Recommended Nutritient Intakes were re-examined for each sex and age group and compared with the current literature. Results: Major revisions in the 2025 KDRIs were driven by updates in the reference bodyweight, improved consistency in rounding and coefficients of variation, inclusion of studies in East Asian populations, and clarification of the use of calcium balance studies.Nevertheless, further studies in Koreans, particularly in pregnant and lactating women, are needed to strengthen the scientific evidence for the calcium DRI. Conclusion The 2025 KDRIs for calcium were revised to be based on more robust logical reasoning and calculation methods. Future research conducted on Korean populations is necessary to define the calcium requirements for Koreans more accurately.

Purpose: Adolescents with same-sex or both-sex sexual experience face disproportionate health risks, yet research has predominantly examined single health problems rather than their multidimensional patterns. This study employed latent class analysis (LCA) to identify distinct health typological classes among Korean adolescents and characterize the distribution of sexual behavior patterns across these classes. Methods: We analyzed 278,066 middle- and high-school students in the 2013–2016 Korea Youth Risk Behavior Survey. The LCA used 17 indicators encompassing sexual behavior patterns, health behaviors, health perceptions, and mental health. Complex-sample weighted analyses examined associations between latent classes and sociodemographic characteristics, sexual behaviors, and diseases. Results: Four distinct classes were identified: mental health high-risk group (10.1%), substance use high-risk group (6.5%), average group (36.3%), and healthy group (47.1%). Adolescents with same-sex or both-sex sexual experience were disproportionately concentrated in the two high-risk classes, comprising 3.3% of the mental health high-risk group and 4.1% of the substance use high-risk group, compared with only 0.3% and 0.5% of the average group and the healthy group. The mental health high-risk group exhibited extremely elevated prevalence rates of suicidal ideation (96.2%), depressive symptoms (88.5%), and suicide attempts (27.5%), while the substance use high-risk group showed high rates of smoking (82.4%) and alcohol use (84.6%) but better mental health. Conclusion Adolescents with same-sex or both-sex sexual experience demonstrate health inequality through disproportionate classification in the mental health high-risk group and the substance use high-risk group. The findings underscore the need for integrated interventions combining mental health support and substance use prevention.

Background: The diagnostic accuracy of preoperative radiologic findings in predicting the tumor characteristics and clinical outcomes of papillary thyroid microcarcinoma (PTMC) was evaluated across all risk groups. Methods: In total, 939 PTMC patients, comprising both low-risk and non-low-risk groups, who underwent surgery were enrolled. The preoperative tumor size and lymph node metastasis (LNM) were evaluated by ultrasonography within 6 months before surgery and compared with the postoperative pathologic findings. Discrepancies between the preoperative and postoperative tumor sizes were analyzed, and clinical outcomes were assessed. Results: The agreement rate between radiological and pathological tumor size was approximately 60%. Significant discrepancies were noted, including an increase in tumor size in 24.3% of cases. Notably, in 10.8% of patients, the postoperative tumor size exceeded 1 cm, despite being initially classified as 0.5 to 1.0 cm based on preoperative imaging. A postoperative tumor size >1 cm was associated with aggressive pathologic factors such as multiplicity, microscopic extrathyroidal extension, and LNM, as well as a higher risk of distant metastasis. In 30.1% of patients, LNM was diagnosed after surgery despite not being suspected before the procedure. This group was characterized by smaller metastatic foci and lower risks of distant metastasis or recurrence than patients with LNM detected both before and after surgery. Conclusion Among all risk groups of PTMCs, a subset showed an increase in tumor size, reaching 1 cm after surgery. These cases require special consideration due to their association with adverse clinical outcomes, including an elevated risk of distant metastasis.

Objective: The Children in Disaster: Evaluation and Recovery (CIDER) program in Korea was developed to treat children and adolescents exposed to trauma. This study aimed to demonstrate the effectiveness of the CIDER through a comparison with controls. Methods: A total of 85 participants consisted of the intervention group (n=41) and control group (n=44). We assessed the changes in trauma-related symptoms, depression, anxiety, and improvements in quality of life before and after the intervention. Results: In total, bullying and school violence (44.7%) were the most common trauma, followed by sexual abuse (17.6%). Acute stress disorder and post-traumatic stress disorder (PTSD) accounted for 41.2%, and attention-deficit/hyperactivity disorder (ADHD) and developmental disorder were the most common comorbidities (51.8%). The symptoms of trauma, depression, anxiety, and quality of life improved significantly in the intervention group, while the control group did not show significant changes. Conclusion Compared with the control group, the CIDER improved symptoms and quality of life in children and adolescents who had experienced trauma. The CIDER program was practical and easy to apply, even for different ages, types of traumas, and comorbidities.

Background: We investigated the effects of sevoflurane exposure on the expression of matrix metalloproteinase (MMP), expression and ablation of natural killer group 2, member D (NKG2D) ligands (UL16-binding proteins 1–3 and major histocompatibility complex class I chain-related molecules A/B), and natural killer (NK) cell-mediated cytotoxicity in breast cancer cells. Methods: Three human breast cancer cell lines (MCF-7, MDA-MB-453, and HCC-70) were incubated with 0 (control), 600 (S6), or 1200 μM (S12) sevoflurane for 4 h. The gene expression of NKG2D ligands and their protein expression on cancer cell surfaces were measured using multiplex polymerase chain reaction (PCR) and flow cytometry, respectively. Protein expression of MMP-1 and -2 and the concentration of soluble NKG2D ligands were analyzed using western blotting and enzyme-linked immunosorbent assays, respectively. Results: Sevoflurane downregulated the mRNA and protein expression of the NKG2D ligand in a dose-dependent manner in MCF-7, MDA-MB-453, and HCC-70 cells but did not affect the expression of MMP-1 or -2 or the concentration of soluble NKG2D ligands in the MCF-7, MDA-MB-453, and HCC-70 cells. Sevoflurane attenuated NK cell-mediated cancer cell lysis in a dose-dependent manner in MCF-7, MDA-MB-453, and HCC-70 cells (P = 0.040, P = 0.040, and P = 0.040, respectively). Conclusions Our results demonstrate that sevoflurane exposure attenuates NK cell-mediated cytotoxicity in breast cancer cells in a dose-dependent manner. This could be attributed to a sevoflurane-induced decrease in the transcription of NKG2D ligands rather than sevoflurane-induced changes in MMP expression and their proteolytic activity.

Humanity is in the midst of the coronavirus disease 2019 (COVID-19) pandemic, and vaccines—including mRNA vaccines—have been developed at an unprecedented speed. It is necessary to develop guidelines for vaccination for people undergoing treatment with assisted reproductive technology (ART) and for pregnancy-related situations based on the extant laboratory and clinical data. COVID-19 vaccines do not appear to adversely affect gametes, embryos, or implantation; therefore, active vaccination is recommended for women or men who are preparing for ART. The use of intravenous immunoglobulin G (IVIG) for the treatment of immune-related infertility is unlikely to impact the effectiveness of the vaccines, so COVID-19 vaccines can be administered around ART cycles in which IVIG is scheduled. Pregnant women have been proven to be at risk of severe maternal and neonatal complications from COVID-19. It does not appear that COVID-19 vaccines harm pregnant women or fetuses; instead, they have been observed to deliver antibodies against severe acute respiratory syndrome coronavirus 2 (SARSCoV-2) to the fetus. Accordingly, it is recommended that pregnant women receive COVID-19 vaccination. There is no rationale for adverse effects, or clinical cases of adverse reactions, in mothers or neonates after COVID-19 vaccination in lactating women. Instead, antibodies to SARS-CoV-2 can be delivered through breast milk. Therefore, breastfeeding mothers should consider vaccination. In summary, active administration of COVID-19 vaccines will help ensure the safe implementation of ART, pregnancy, and breastfeeding.

Complex chromosome rearrangements (CCRs) are structural chromosomal rearrangements involving at least three chromosomes and more than two breakpoints. CCR carriers are generally phenotypically normal but related to higher risk of recurrent miscarriage and having abnormal offspring with congenital anomalies. However, most of CCR carriers are not aware of their condition until genetic analysis of either abortus or affected baby or parental karyotyping is performed. Herein, we present the case that CCR carrier patients can be identified by preimplantation genetic testing of preimplantation embryos. An infertile male patient with severe oligoasthenoteratozoospermia was diagnosed balanced reciprocal translocation, 46,XY,t(3;11) (p26;p14) at first. After attempting the first preimplantation genetic testing for structural rearrangement (PGT-SR) cycle, we found the recurrent segmental gain or loss on 21q21.3-q22.3 of five out of nine embryos. As a result of karyotype re-analysis, the patient’s karyotype showed a balanced CCR involving chromosomes 3, 11, and 21 with three breakpoints 3p26, 11p14, and 21q21. The patient underwent two PGT-SR cycles, and a pregnancy was established after the transfer of an euploid embryo in the second cycle. Amniocentesis confirmed that the baby carried normal karyotype without mosaicism. At 37 weeks gestation, a healthy girl weighting 3,050 g was born.

Organized hematoma of maxillary sinus is a rare pathologically benign mass in which pressure in the hematoma increases as it undergoes a process of organization, causing the deformation of the surrounding tissue, mimicking malignancies. The midfacial degloving approach can be used when extensive exposure is required in the treatment of lesions or traumas in the midfacial area with intranasal and intraoral incisions. We report a surgical excision case of organized hematoma of maxillary sinus using midfacial degloving approach without major complications and recurrence after one-year follow up.

Radical trachelectomy is a fertility-preserving alternative to radical hysterectomy in carefully selected young women with early-stage cervical cancer. However, in cases with subsequent severe cervical stenosis, assisted reproductive techniques can be difficult. This is a case report of a 34-year-old patient who underwent robot-assisted radical trachelectomy and cerclage for early-stage (IB2) adenosquamous carcinoma. Three months after surgery, the patient underwent ovarian stimulation using a gonadotropin-releasing hormone antagonist protocol. As it was impossible to perform transcervical embryo transfer due to the almost complete absence of the cervical opening, transmyometrial embryo transfer under ultrasound guidance was performed. This resulted in a successful singleton pregnancy. This is the first case of successful pregnancy conceived by in vitro fertilization with transmyometrial embryo transfer in a patient who had previously undergone robot-assisted radical trachelectomy.