Osteoid osteoma accounts for approximately 10% of all benign bone tumors, but only approximately 4% of cases occur in the foot and ankle area. Periarticular osteoid osteoma frequently manifests with nonspecific clinical symptoms that mimic other conditions, potentially leading clinicians down a diagnostic side path and resulting in delayed or missed diagnoses compared to extra-articular osteoid osteoma. Although plain radiographs may show nonspecific findings, magnetic resonance imaging can detect bone marrow edema and surrounding soft tissue changes. Computed tomography is the most accurate modality for diagnosis. This paper reports the case of a 26-year-old female diagnosed with periarticular osteoid osteoma of the calcaneus and was treated with arthroscopic localized curettage at the author’s institution.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease that culminates in respiratory failure and death due to irreversible scarring of the distal lung. While initially considered a chronic inflammatory disorder, the aberrant function of the alveolar epithelium is now acknowledged as playing a central role in the pathophysiology of IPF. This study aimed to investigate the regenerative capacity of alveolar type 2 (AT2) cells using IPF-derived alveolar organoids and to examine the effects of disease progression on this capacity. Methods: Lung tissues from three pneumothorax patients and six IPF patients (early and advanced stages) were obtained through video-assisted thoracoscopic surgery and lung transplantation. HTII-280+ cells were isolated from CD31-CD45-epithelial cell adhesion molecule (EpCAM)+ cells in the distal lungs of IPF and pneumothorax patients using fluorescence-activated cell sorting (FACS) and resuspended in 48-well plates to establish IPF-derived alveolar organoids. Immunostaining was used to verify the presence of AT2 cells. Results: FACS sorting yielded approximately 1% of AT2 cells in early IPF tissue, and the number decreased as the disease progressed, in contrast to 2.7% in pneumothorax. Additionally, the cultured organoids in the IPF groups were smaller and less numerous compared to those from pneumothorax patients. The colony forming efficiency decreased as the disease advanced. Immunostaining results showed that the IPF organoids expressed less surfactant protein C (SFTPC) compared to the pneumothorax group and contained keratin 5+ (KRT5+) cells. Conclusion This study confirmed that the regenerative capacity of AT2 cells in IPF decreases as the disease progresses, with IPF-derived AT2 cells inherently exhibiting functional abnormalities and altered differentiation plasticity.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease that culminates in respiratory failure and death due to irreversible scarring of the distal lung. While initially considered a chronic inflammatory disorder, the aberrant function of the alveolar epithelium is now acknowledged as playing a central role in the pathophysiology of IPF. This study aimed to investigate the regenerative capacity of alveolar type 2 (AT2) cells using IPF-derived alveolar organoids and to examine the effects of disease progression on this capacity. Methods: Lung tissues from three pneumothorax patients and six IPF patients (early and advanced stages) were obtained through video-assisted thoracoscopic surgery and lung transplantation. HTII-280+ cells were isolated from CD31-CD45-epithelial cell adhesion molecule (EpCAM)+ cells in the distal lungs of IPF and pneumothorax patients using fluorescence-activated cell sorting (FACS) and resuspended in 48-well plates to establish IPF-derived alveolar organoids. Immunostaining was used to verify the presence of AT2 cells. Results: FACS sorting yielded approximately 1% of AT2 cells in early IPF tissue, and the number decreased as the disease progressed, in contrast to 2.7% in pneumothorax. Additionally, the cultured organoids in the IPF groups were smaller and less numerous compared to those from pneumothorax patients. The colony forming efficiency decreased as the disease advanced. Immunostaining results showed that the IPF organoids expressed less surfactant protein C (SFTPC) compared to the pneumothorax group and contained keratin 5+ (KRT5+) cells. Conclusion This study confirmed that the regenerative capacity of AT2 cells in IPF decreases as the disease progresses, with IPF-derived AT2 cells inherently exhibiting functional abnormalities and altered differentiation plasticity.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease that culminates in respiratory failure and death due to irreversible scarring of the distal lung. While initially considered a chronic inflammatory disorder, the aberrant function of the alveolar epithelium is now acknowledged as playing a central role in the pathophysiology of IPF. This study aimed to investigate the regenerative capacity of alveolar type 2 (AT2) cells using IPF-derived alveolar organoids and to examine the effects of disease progression on this capacity. Methods: Lung tissues from three pneumothorax patients and six IPF patients (early and advanced stages) were obtained through video-assisted thoracoscopic surgery and lung transplantation. HTII-280+ cells were isolated from CD31-CD45-epithelial cell adhesion molecule (EpCAM)+ cells in the distal lungs of IPF and pneumothorax patients using fluorescence-activated cell sorting (FACS) and resuspended in 48-well plates to establish IPF-derived alveolar organoids. Immunostaining was used to verify the presence of AT2 cells. Results: FACS sorting yielded approximately 1% of AT2 cells in early IPF tissue, and the number decreased as the disease progressed, in contrast to 2.7% in pneumothorax. Additionally, the cultured organoids in the IPF groups were smaller and less numerous compared to those from pneumothorax patients. The colony forming efficiency decreased as the disease advanced. Immunostaining results showed that the IPF organoids expressed less surfactant protein C (SFTPC) compared to the pneumothorax group and contained keratin 5+ (KRT5+) cells. Conclusion This study confirmed that the regenerative capacity of AT2 cells in IPF decreases as the disease progresses, with IPF-derived AT2 cells inherently exhibiting functional abnormalities and altered differentiation plasticity.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease that culminates in respiratory failure and death due to irreversible scarring of the distal lung. While initially considered a chronic inflammatory disorder, the aberrant function of the alveolar epithelium is now acknowledged as playing a central role in the pathophysiology of IPF. This study aimed to investigate the regenerative capacity of alveolar type 2 (AT2) cells using IPF-derived alveolar organoids and to examine the effects of disease progression on this capacity. Methods: Lung tissues from three pneumothorax patients and six IPF patients (early and advanced stages) were obtained through video-assisted thoracoscopic surgery and lung transplantation. HTII-280+ cells were isolated from CD31-CD45-epithelial cell adhesion molecule (EpCAM)+ cells in the distal lungs of IPF and pneumothorax patients using fluorescence-activated cell sorting (FACS) and resuspended in 48-well plates to establish IPF-derived alveolar organoids. Immunostaining was used to verify the presence of AT2 cells. Results: FACS sorting yielded approximately 1% of AT2 cells in early IPF tissue, and the number decreased as the disease progressed, in contrast to 2.7% in pneumothorax. Additionally, the cultured organoids in the IPF groups were smaller and less numerous compared to those from pneumothorax patients. The colony forming efficiency decreased as the disease advanced. Immunostaining results showed that the IPF organoids expressed less surfactant protein C (SFTPC) compared to the pneumothorax group and contained keratin 5+ (KRT5+) cells. Conclusion This study confirmed that the regenerative capacity of AT2 cells in IPF decreases as the disease progresses, with IPF-derived AT2 cells inherently exhibiting functional abnormalities and altered differentiation plasticity.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease that culminates in respiratory failure and death due to irreversible scarring of the distal lung. While initially considered a chronic inflammatory disorder, the aberrant function of the alveolar epithelium is now acknowledged as playing a central role in the pathophysiology of IPF. This study aimed to investigate the regenerative capacity of alveolar type 2 (AT2) cells using IPF-derived alveolar organoids and to examine the effects of disease progression on this capacity. Methods: Lung tissues from three pneumothorax patients and six IPF patients (early and advanced stages) were obtained through video-assisted thoracoscopic surgery and lung transplantation. HTII-280+ cells were isolated from CD31-CD45-epithelial cell adhesion molecule (EpCAM)+ cells in the distal lungs of IPF and pneumothorax patients using fluorescence-activated cell sorting (FACS) and resuspended in 48-well plates to establish IPF-derived alveolar organoids. Immunostaining was used to verify the presence of AT2 cells. Results: FACS sorting yielded approximately 1% of AT2 cells in early IPF tissue, and the number decreased as the disease progressed, in contrast to 2.7% in pneumothorax. Additionally, the cultured organoids in the IPF groups were smaller and less numerous compared to those from pneumothorax patients. The colony forming efficiency decreased as the disease advanced. Immunostaining results showed that the IPF organoids expressed less surfactant protein C (SFTPC) compared to the pneumothorax group and contained keratin 5+ (KRT5+) cells. Conclusion This study confirmed that the regenerative capacity of AT2 cells in IPF decreases as the disease progresses, with IPF-derived AT2 cells inherently exhibiting functional abnormalities and altered differentiation plasticity.

Objectives: The main Brucella species causing human infections in the Republic of Korea is Brucella abortus, which uses cattle as its host. However, since 2014, Brucella melitensis, whichuses sheep and goats as hosts, has also been identified. This study investigated whether a shifthas occurred in the predominant species of Brucella pathogens. Methods: Brucellosis is a class 3 infectious disease requiring mandatory reporting and registration in the Korea Disease Control and Prevention Agency’s infectious disease surveillance system (http://is.kdca.go.kr). Cases from 2014 to 2023 were studied, and whole-genome sequencing analysis was conducted using BruMLSA21. Results: Out of 51 patients, males (45 patients, 88.2%) were predominantly affected. Twentyfive patients (49%) came from the livestock industry, and within the livestock sector group, the route of infection occurred exclusively through contact (25/25, 100%), whereas in other occupations, it was split between contact (9/26 patients, 34.6%) and ingestion (8/26 patients, 30.8%). Among the 31 patients who underwent Brucella culture tests, B. melitensis was found to be more prevalent than B. abortus (14 patients, 45.2% vs. 11 patients, 35.5%). In all cases where B. melitensis was isolated, the infections were of foreign origin, consistent with the results ofBruMLSA21. Conclusion Regular monitoring of the causative agent of brucellosis is necessary due to its varying host preferences and antibiotic resistance. Furthermore, given the increasing prevalence of B. melitensis worldwide, changes in dietary habits (e.g., increased lamb consumption), and the increase in foreign workers and Chinese immigrants, a multi-ministerial One Health response will be required.

Purpose: For the treatment of locally advanced rectal cancer (LARC), research on primary lesions with mesorectal fascia (MRF) involvement is lacking. This study analyzed the clinical outcomes and efficacy of dose-escalated neoadjuvant concurrent chemoradiotherapy (NCRT) to patients with LARC involving MRF. Materials and Methods: We retrospectively reviewed 301 patients who were diagnosed with LARC involving MRF and underwent NCRT followed by total mesorectal excision (TME). Patients who received radiotherapy (RT) doses of ≤50.4 Gy were defined as the non-boost group, while ≥54.0 Gy as the boost group. Pathological tumor response and survival outcomes, including intrapelvic recurrence-free survival (IPRFS), distant metastases-free survival (DMFS) and overall survival (OS), were analyzed. Results: A total of 269 patients (89.4%) achieved a negative pathological circumferential resection margin and 104 (34.6%) had good pathological tumor regression grades. With a median follow-up of 32.4 months, IPRFS, DMFS, and OS rates at 5-years were 88.6%, 78.0%, and 91.2%, respectively. In the subgroup analysis by RT dose, the boost group included more advanced clinical stages of patients. For the non-boost group and boost group, 5-year IPRFS rates were 90.3% and 87.0% (p = 0.242), 5-year DMFS rates were 82.0% and 71.3% (p = 0.105), and 5-year OS rates were 93.0% and 80.6% (p = 0.439), respectively. Treatment related toxicity was comparable between the two groups (p = 0.211). Conclusion Although this retrospective study failed to confirm the efficacy of dose-escalated NCRT, favorable IPRFS and pathological complete response was achieved with NCRT followed by TME. Further studies combining patient customized RT dose with systemic therapies are needed.

Objectives: The main Brucella species causing human infections in the Republic of Korea is Brucella abortus, which uses cattle as its host. However, since 2014, Brucella melitensis, whichuses sheep and goats as hosts, has also been identified. This study investigated whether a shifthas occurred in the predominant species of Brucella pathogens. Methods: Brucellosis is a class 3 infectious disease requiring mandatory reporting and registration in the Korea Disease Control and Prevention Agency’s infectious disease surveillance system (http://is.kdca.go.kr). Cases from 2014 to 2023 were studied, and whole-genome sequencing analysis was conducted using BruMLSA21. Results: Out of 51 patients, males (45 patients, 88.2%) were predominantly affected. Twentyfive patients (49%) came from the livestock industry, and within the livestock sector group, the route of infection occurred exclusively through contact (25/25, 100%), whereas in other occupations, it was split between contact (9/26 patients, 34.6%) and ingestion (8/26 patients, 30.8%). Among the 31 patients who underwent Brucella culture tests, B. melitensis was found to be more prevalent than B. abortus (14 patients, 45.2% vs. 11 patients, 35.5%). In all cases where B. melitensis was isolated, the infections were of foreign origin, consistent with the results ofBruMLSA21. Conclusion Regular monitoring of the causative agent of brucellosis is necessary due to its varying host preferences and antibiotic resistance. Furthermore, given the increasing prevalence of B. melitensis worldwide, changes in dietary habits (e.g., increased lamb consumption), and the increase in foreign workers and Chinese immigrants, a multi-ministerial One Health response will be required.

Objectives: The main Brucella species causing human infections in the Republic of Korea is Brucella abortus, which uses cattle as its host. However, since 2014, Brucella melitensis, whichuses sheep and goats as hosts, has also been identified. This study investigated whether a shifthas occurred in the predominant species of Brucella pathogens. Methods: Brucellosis is a class 3 infectious disease requiring mandatory reporting and registration in the Korea Disease Control and Prevention Agency’s infectious disease surveillance system (http://is.kdca.go.kr). Cases from 2014 to 2023 were studied, and whole-genome sequencing analysis was conducted using BruMLSA21. Results: Out of 51 patients, males (45 patients, 88.2%) were predominantly affected. Twentyfive patients (49%) came from the livestock industry, and within the livestock sector group, the route of infection occurred exclusively through contact (25/25, 100%), whereas in other occupations, it was split between contact (9/26 patients, 34.6%) and ingestion (8/26 patients, 30.8%). Among the 31 patients who underwent Brucella culture tests, B. melitensis was found to be more prevalent than B. abortus (14 patients, 45.2% vs. 11 patients, 35.5%). In all cases where B. melitensis was isolated, the infections were of foreign origin, consistent with the results ofBruMLSA21. Conclusion Regular monitoring of the causative agent of brucellosis is necessary due to its varying host preferences and antibiotic resistance. Furthermore, given the increasing prevalence of B. melitensis worldwide, changes in dietary habits (e.g., increased lamb consumption), and the increase in foreign workers and Chinese immigrants, a multi-ministerial One Health response will be required.