1.Diagnostic Accuracy of Serological Tests for Mycoplasma pneumoniae Infections in Children with Pneumonia, Based on Symptom Onset
Gahee KIM ; Ki Wook YUN ; Dayun KANG ; Taek Jin LEE ; Byung Wook EUN ; Hyunju LEE ; Yae-Jean KIM ; Doo Ri KIM ; Areum SHIN ; Hyun Mi KANG ; Ye Ji KIM ; Byung Ok KWAK ; Younghee LEE ; Ye Kyung KIM ; Young June CHOE ; Woosuck SUH ; Kyo Jin JO ; Kyung-Ran KIM ; Eun Young CHO ; Kyung Min KIM ; Joon Kee LEE ; Su Eun PARK
Annals of Laboratory Medicine 2026;46(2):162-170
Background:
Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in children, with a rising incidence of macrolide resistance. Early diagnosis is crucial for reducing the disease burden; however, current diagnostic tools have limitations.We evaluated the diagnostic accuracy of serological assays and their performance based on symptom onset in children with CAP.
Methods:
From September 2023 to September 2024, we prospectively enrolled children with CAP, classified as M. pneumoniae pneumonia (MPP) or non-MPP, from 16 hospitals in Korea. Serological testing included chemiluminescence immunoassay (CLIA) and ELISA for detecting IgM and IgG, along with particle agglutination (PA) for total antibody measurements. Serological responses were analyzed at different times after symptom onset (0–4, 5–9, and 10–21 days).
Results:
Among 472 children with CAP (362 MPP, 110 non-MPP), 138 (29.2%) underwent PA testing, and 334 (70.8%) underwent IgM testing. PA at a 1:640 cutoff showed 48.0% sensitivity and 100% specificity. CLIA and ELISA showed comparable sensitivities (69.1% vs. 69.2%) and specificities (76.9% vs. 66.7%) for IgM testing. Seropositivity increased significantly with time since symptom onset (P for trend < 0.001), reaching 97.9% for IgM, 62.5% for IgG, and 94.7% for PA at 10–21 days.
Conclusions
The time post-symptom onset significantly influenced the diagnostic utility of serological tests for pediatric MPP, which showed limited value during the early stage of illness. These findings emphasize the importance of symptom onset-based interpretation of serological test results and their utility in complementing PCR when optimizing MPP diagnosis in children.
2.Development and Validation of an Analytical Method for the Simultaneous Determination of Three Marker Compounds in Wikstroemia trichotoma
Min-Ji KEEM ; Taek-Hwan KWON ; Beom-Geun JO ; Sangho CHOI ; Jin-Hyub PAIK ; Young Suk JUNG ; Eun-Ju JEONG ; Su-Nam KIM ; Min Hye YANG
Natural Product Sciences 2026;32(1):84-92
The Wikstroemia genus is highly regarded in traditional Asian medicine for its diverse therapeutic applications, including the treatment of inflammatory and infectious conditions. Among its members,Wikstroemia trichotoma (Thunb.) Makino remains a promising medicinal resource which is yet to be chemicallycharacterized. To ensure the chemical consistency of W. trichotoma, we developed and validated the first HPLC method for the simultaneous quantification of three major marker compounds: chlorogenic acid (1), miconioside B (2), and matteucinol 7-O-apiofuranosyl(1→6)-glucopyranoside (3). Chromatographic separation was achieved on a C18 column using a gradient elution system of 0.1% formic acid in water and 0.1% formic acid in acetonitrile. Detection was optimized using a photodiode array (PDA) detector at 280 and 325 nm, based on the absorption maxima of the markers. The method was validated in accordance with the International Council for Harmonisation (ICH) and the Ministry of Food and Drug Safety (MFDS) guidelines. The results demonstrated high linearity (r2 > 0.999), with limits of detection and quantitation ranging from 4.28–6.42 and 12.97–19.47 μg/ mL, respectively. Intra- and inter-day precision (% RSD ≤ 1.83%) and accuracy (recoveries of 92.5–101.7%) were within acceptable limits. Quantitative analysis revealed the contents of 1, 2, and 3 in the W. trichotoma extract to be 19.9, 139.8, and 264.9 mg/g, respectively. This study provides a reliable analytical framework for the standardization, quality control, and future pharmacological evaluation of W. trichotoma.
3.c-Kit signaling confers damage-resistance to sweet taste cells upon nerve injury.
Su Young KI ; Jea Hwa JANG ; Dong-Hoon KIM ; Yong Taek JEONG
International Journal of Oral Science 2025;17(1):57-57
Taste buds relay taste sensory information to the primary taste neurons but depend on those same neurons for essential components to maintain function. While denervation-induced taste bud degeneration and subsequent regeneration were discovered decades ago, the mechanisms underlying these phenomena (e.g., heterogenous cellular responses to nerve injury and the signaling pathways involved) remain poorly understood. Here, using mouse genetics, nerve injury models, pharmacologic manipulation, and taste bud organoid models, we identify a specific subpopulation of taste cells, predominantly c-Kit-expressing sweet cells, that exhibit superior resistance to nerve injury. We found the c-Kit inhibitor imatinib selectively reduced the number of residual c-Kit-expressing sweet cells at post-operation week 2, subsequently attenuating the re-emergence of other type II cells by post-operation week 4. In taste bud organoids, c-Kit-expressing cells were resistant to R-spondin withdrawal but susceptible to imatinib, while other taste cell types showed the opposite behavior. We also observed a distinct population of residual taste cells that acquired stem-like properties, generating clonal descendent cells among suprabasal keratinocytes independent of c-Kit signaling. Together, our findings reveal that c-Kit signaling confers resilience on c-Kit-expressing sweet cells and supports the broader reconstruction of taste buds during the later regenerative stage following nerve injury.
Animals
;
Taste Buds/metabolism*
;
Proto-Oncogene Proteins c-kit/metabolism*
;
Mice
;
Signal Transduction
;
Imatinib Mesylate/pharmacology*
;
Mice, Inbred C57BL
4.Comparative analysis of novel damping capacity analysis devices for assessing implant stability in clinical practice
Su-Bin HONG ; Bo-Ah LEE ; Woo-Ri LEE ; Jung-Seok LEE ; Young-Taek KIM
Journal of Periodontal & Implant Science 2025;55(6):462-472
Purpose:
Implant stability testing is crucial for verifying osseointegration before prosthetic loading. Several methods have been developed to assess osseointegration. Among these, damping capacity analysis (DCA) devices offer a user-friendly and non-invasive approach.In this study, we evaluated the accuracy and reliability of newly available DCA devices in assessing dental implant stability.
Methods:
This study included 58 implants from 37 patients over a 1-month period. Three measurements per implant were obtained with healing abutments in place, following the manufacturers’ guidelines, using the DCA-P (Periotest M, Medizintechnik Gulden), DCA-A (Anycheck, Neobiotech), and DCA-T (The Trust, Dentium) devices. Factors such as healing abutment height, time since placement, bone grafting, fixture diameter, and fixture length were evaluated. Accuracy was assessed using DCA-P as the reference, and reproducibility was statistically analyzed using 3 measurements per implant. Statistical analyses were performed with SPSS Statistics 23.0 (IBM Corp.).
Results:
All implants that passed the stability tests using DCA devices were restored with definitive prostheses and showed no signs of early failure. The DCA-A value demonstrated a very strong correlation with the DCA-P value (DCAV-P), whereas the DCA-T value exhibited only a moderate correlation with DCAV-P. DCA-P also showed the highest reliability, followed by DCA-A and then DCA-T. The reliability of DCA-A and DCA-T was not significantly affected by any of the assessed factors; in contrast, DCA-P’s reliability was significantly influenced by arch location and specific quadrant position.
Conclusions
With DCA-P as the reference, DCA-A demonstrated superior accuracy compared to DCA-T. Although DCA-P exhibited the highest reliability, its performance was significantly affected by the positional factors of the target implant.
5.Efficacy of intravesical gemcitabine instillation compared with intravesical Bacillus Calmette-Guérin instillation for non-muscle invasive bladder cancer
Dong Ha KIM ; Taek Sang KIM ; Su Hwan KANG ; Seong Bin KIM
Kosin Medical Journal 2024;39(4):254-258
Background:
Intravesical Bacillus Calmette-Guérin (BCG) instillation is the most effective treatment for reducing intravesical recurrence in non-muscle invasive bladder cancer (NMIBC). However, due to the recent global shortage of BCG, there is an increasing need for alternative treatments. This study aimed to retrospectively compare the outcomes of patients treated with intravesical gemcitabine instillation and BCG instillation as initial treatment options for NMIBC.
Methods:
Seventy-eight patients with NMIBC who underwent transurethral resection of bladder tumors between January 2022 and September 2023 were reviewed. Of these, 42 patients received intravesical gemcitabine instillation, and 36 patients received BCG instillation. Recurrence-free survival (RFS) was analyzed, along with tumor multiplicity, grade, T stage, size, and bladder storage time after instillation, which could influence RFS.
Results:
The mean follow-up period was 18.7 months for the gemcitabine group and 20.6 months for the BCG group. Recurrence occurred in 46.15% of patients (52.38% in the gemcitabine group and 38.92% in the BCG group). Tumor characteristics, including multiplicity, grade, stage, and size, were not significantly different between the two groups. The mean RFS was 15.92 months in the gemcitabine group and 19.84 months in the BCG group, with no statistically significant difference (p=0.397). However, gemcitabine instillation caused more severe bladder irritation, with shorter bladder storage time.
Conclusions
Intravesical gemcitabine and BCG instillation yielded comparable RFS outcomes. However, gemcitabine led to more severe bladder irritation, highlighting the need for further studies to optimize its application.
6.Efficacy of intravesical gemcitabine instillation compared with intravesical Bacillus Calmette-Guérin instillation for non-muscle invasive bladder cancer
Dong Ha KIM ; Taek Sang KIM ; Su Hwan KANG ; Seong Bin KIM
Kosin Medical Journal 2024;39(4):254-258
Background:
Intravesical Bacillus Calmette-Guérin (BCG) instillation is the most effective treatment for reducing intravesical recurrence in non-muscle invasive bladder cancer (NMIBC). However, due to the recent global shortage of BCG, there is an increasing need for alternative treatments. This study aimed to retrospectively compare the outcomes of patients treated with intravesical gemcitabine instillation and BCG instillation as initial treatment options for NMIBC.
Methods:
Seventy-eight patients with NMIBC who underwent transurethral resection of bladder tumors between January 2022 and September 2023 were reviewed. Of these, 42 patients received intravesical gemcitabine instillation, and 36 patients received BCG instillation. Recurrence-free survival (RFS) was analyzed, along with tumor multiplicity, grade, T stage, size, and bladder storage time after instillation, which could influence RFS.
Results:
The mean follow-up period was 18.7 months for the gemcitabine group and 20.6 months for the BCG group. Recurrence occurred in 46.15% of patients (52.38% in the gemcitabine group and 38.92% in the BCG group). Tumor characteristics, including multiplicity, grade, stage, and size, were not significantly different between the two groups. The mean RFS was 15.92 months in the gemcitabine group and 19.84 months in the BCG group, with no statistically significant difference (p=0.397). However, gemcitabine instillation caused more severe bladder irritation, with shorter bladder storage time.
Conclusions
Intravesical gemcitabine and BCG instillation yielded comparable RFS outcomes. However, gemcitabine led to more severe bladder irritation, highlighting the need for further studies to optimize its application.
7.Efficacy of intravesical gemcitabine instillation compared with intravesical Bacillus Calmette-Guérin instillation for non-muscle invasive bladder cancer
Dong Ha KIM ; Taek Sang KIM ; Su Hwan KANG ; Seong Bin KIM
Kosin Medical Journal 2024;39(4):254-258
Background:
Intravesical Bacillus Calmette-Guérin (BCG) instillation is the most effective treatment for reducing intravesical recurrence in non-muscle invasive bladder cancer (NMIBC). However, due to the recent global shortage of BCG, there is an increasing need for alternative treatments. This study aimed to retrospectively compare the outcomes of patients treated with intravesical gemcitabine instillation and BCG instillation as initial treatment options for NMIBC.
Methods:
Seventy-eight patients with NMIBC who underwent transurethral resection of bladder tumors between January 2022 and September 2023 were reviewed. Of these, 42 patients received intravesical gemcitabine instillation, and 36 patients received BCG instillation. Recurrence-free survival (RFS) was analyzed, along with tumor multiplicity, grade, T stage, size, and bladder storage time after instillation, which could influence RFS.
Results:
The mean follow-up period was 18.7 months for the gemcitabine group and 20.6 months for the BCG group. Recurrence occurred in 46.15% of patients (52.38% in the gemcitabine group and 38.92% in the BCG group). Tumor characteristics, including multiplicity, grade, stage, and size, were not significantly different between the two groups. The mean RFS was 15.92 months in the gemcitabine group and 19.84 months in the BCG group, with no statistically significant difference (p=0.397). However, gemcitabine instillation caused more severe bladder irritation, with shorter bladder storage time.
Conclusions
Intravesical gemcitabine and BCG instillation yielded comparable RFS outcomes. However, gemcitabine led to more severe bladder irritation, highlighting the need for further studies to optimize its application.
8.Efficacy of intravesical gemcitabine instillation compared with intravesical Bacillus Calmette-Guérin instillation for non-muscle invasive bladder cancer
Dong Ha KIM ; Taek Sang KIM ; Su Hwan KANG ; Seong Bin KIM
Kosin Medical Journal 2024;39(4):254-258
Background:
Intravesical Bacillus Calmette-Guérin (BCG) instillation is the most effective treatment for reducing intravesical recurrence in non-muscle invasive bladder cancer (NMIBC). However, due to the recent global shortage of BCG, there is an increasing need for alternative treatments. This study aimed to retrospectively compare the outcomes of patients treated with intravesical gemcitabine instillation and BCG instillation as initial treatment options for NMIBC.
Methods:
Seventy-eight patients with NMIBC who underwent transurethral resection of bladder tumors between January 2022 and September 2023 were reviewed. Of these, 42 patients received intravesical gemcitabine instillation, and 36 patients received BCG instillation. Recurrence-free survival (RFS) was analyzed, along with tumor multiplicity, grade, T stage, size, and bladder storage time after instillation, which could influence RFS.
Results:
The mean follow-up period was 18.7 months for the gemcitabine group and 20.6 months for the BCG group. Recurrence occurred in 46.15% of patients (52.38% in the gemcitabine group and 38.92% in the BCG group). Tumor characteristics, including multiplicity, grade, stage, and size, were not significantly different between the two groups. The mean RFS was 15.92 months in the gemcitabine group and 19.84 months in the BCG group, with no statistically significant difference (p=0.397). However, gemcitabine instillation caused more severe bladder irritation, with shorter bladder storage time.
Conclusions
Intravesical gemcitabine and BCG instillation yielded comparable RFS outcomes. However, gemcitabine led to more severe bladder irritation, highlighting the need for further studies to optimize its application.
9.Efficacy of intravesical gemcitabine instillation compared with intravesical Bacillus Calmette-Guérin instillation for non-muscle invasive bladder cancer
Dong Ha KIM ; Taek Sang KIM ; Su Hwan KANG ; Seong Bin KIM
Kosin Medical Journal 2024;39(4):254-258
Background:
Intravesical Bacillus Calmette-Guérin (BCG) instillation is the most effective treatment for reducing intravesical recurrence in non-muscle invasive bladder cancer (NMIBC). However, due to the recent global shortage of BCG, there is an increasing need for alternative treatments. This study aimed to retrospectively compare the outcomes of patients treated with intravesical gemcitabine instillation and BCG instillation as initial treatment options for NMIBC.
Methods:
Seventy-eight patients with NMIBC who underwent transurethral resection of bladder tumors between January 2022 and September 2023 were reviewed. Of these, 42 patients received intravesical gemcitabine instillation, and 36 patients received BCG instillation. Recurrence-free survival (RFS) was analyzed, along with tumor multiplicity, grade, T stage, size, and bladder storage time after instillation, which could influence RFS.
Results:
The mean follow-up period was 18.7 months for the gemcitabine group and 20.6 months for the BCG group. Recurrence occurred in 46.15% of patients (52.38% in the gemcitabine group and 38.92% in the BCG group). Tumor characteristics, including multiplicity, grade, stage, and size, were not significantly different between the two groups. The mean RFS was 15.92 months in the gemcitabine group and 19.84 months in the BCG group, with no statistically significant difference (p=0.397). However, gemcitabine instillation caused more severe bladder irritation, with shorter bladder storage time.
Conclusions
Intravesical gemcitabine and BCG instillation yielded comparable RFS outcomes. However, gemcitabine led to more severe bladder irritation, highlighting the need for further studies to optimize its application.
10.Immune Cells Are DifferentiallyAffected by SARS-CoV-2 Viral Loads in K18-hACE2 Mice
Jung Ah KIM ; Sung-Hee KIM ; Jeong Jin KIM ; Hyuna NOH ; Su-bin LEE ; Haengdueng JEONG ; Jiseon KIM ; Donghun JEON ; Jung Seon SEO ; Dain ON ; Suhyeon YOON ; Sang Gyu LEE ; Youn Woo LEE ; Hui Jeong JANG ; In Ho PARK ; Jooyeon OH ; Sang-Hyuk SEOK ; Yu Jin LEE ; Seung-Min HONG ; Se-Hee AN ; Joon-Yong BAE ; Jung-ah CHOI ; Seo Yeon KIM ; Young Been KIM ; Ji-Yeon HWANG ; Hyo-Jung LEE ; Hong Bin KIM ; Dae Gwin JEONG ; Daesub SONG ; Manki SONG ; Man-Seong PARK ; Kang-Seuk CHOI ; Jun Won PARK ; Jun-Won YUN ; Jeon-Soo SHIN ; Ho-Young LEE ; Ho-Keun KWON ; Jun-Young SEO ; Ki Taek NAM ; Heon Yung GEE ; Je Kyung SEONG
Immune Network 2024;24(2):e7-
Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019.In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×105 plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×102 PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×102 PFU-virusinfected lungs from 2 dpi, but not in 1×105 PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×105PFU; however, 1×102 PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

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