Becoming a doctor: using social constructivism and situated learning to understand the clinical clerkship experiences of undergraduate medical students.

BACKGROUND: Despite the emphasis on the uniqueness and educational importance of clinical clerkships in medical education, there is a lack of deep understanding of their educational process and outcomes. Especially due to an inherent trait of clinical clerkships which requires participation in the workplace outside the classroom, it is difficult to fully comprehend their educational potential using traditional learning perspectives such as imbibing outside knowledge. Accordingly, this study aims to explore the experiences of a rotation-based clerkship of medical school students from the perspective of social constructivism of learning, which can empirically examine what and how medical students learn during clinical clerkship in South Korea. By providing an insight into the workings of the clerkship process, this study contributes to a better understanding of how a learning-friendly environment can be cultivated at clinical clerkships. METHODS: The study utilized a basic qualitative study to understand what and how medical students learn during their clinical clerkships. Semi-structured, in-depth individual interviews were conducted with eight sixth-graders who had experienced a two-year clerkship at Ajou University Medical School. Data were analyzed based on Lave and Wenger's situated learning theory and Wenger's social theory in learning. RESULTS: We found that the medical students had developed different aspects of their professional identities such as values, functionality, career decisions, sociality, and situating during their clinical clerkships. Further, professional identity was formed through a combination of participation and reification-the processes involved in the negotiation of meaning. This combination was facilitated by the students' first experience and relationships with professors, classmates, and patients. Finally, non-learning occurred in the context of over-participation (learning anxiety and alienation) or over-reification (evaluation and e-portfolio). CONCLUSIONS: This study revealed five sub-professional identities and their formation process from the learners' perspective, thereby uncovering the unique learning characteristics and advantages of rotated-based clerkship and contributing to a further understanding of how gradual improvements can be made to the traditional clerkship education of medical students.

Twenty-Five Year Trend Change in the Etiology of Pediatric Invasive Bacterial Infections in Korea, 1996-2020.

BACKGROUND: The coronavirus disease-2019 (COVID-19) pandemic has contributed to the change in the epidemiology of many infectious diseases. This study aimed to establish the pre-pandemic epidemiology of pediatric invasive bacterial infection (IBI). METHODS: A retrospective multicenter-based surveillance for pediatric IBIs has been maintained from 1996 to 2020 in Korea. IBIs caused by eight bacteria (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyogenes, Listeria monocytogenes, and Salmonella species) in immunocompetent children > 3 months of age were collected at 29 centers. The annual trend in the proportion of IBIs by each pathogen was analyzed. RESULTS: A total of 2,195 episodes were identified during the 25-year period between 1996 and 2020. S. pneumoniae (42.4%), S. aureus (22.1%), and Salmonella species (21.0%) were common in children 3 to 59 months of age. In children ≥ 5 years of age, S. aureus (58.1%), followed by Salmonella species (14.8%) and S. pneumoniae (12.2%) were common. Excluding the year 2020, there was a trend toward a decrease in the relative proportions of S. pneumoniae (rs = -0.430, P = 0.036), H. influenzae (rs = -0.922, P < 0.001), while trend toward an increase in the relative proportion of S. aureus (rs = 0.850, P < 0.001), S. agalactiae (rs = 0.615, P = 0.001), and S. pyogenes (rs = 0.554, P = 0.005). CONCLUSION: In the proportion of IBIs over a 24-year period between 1996 and 2019, we observed a decreasing trend for S. pneumoniae and H. influenzae and an increasing trend for S. aureus, S. agalactiae, and S. pyogenes in children > 3 months of age. These findings can be used as the baseline data to navigate the trend in the epidemiology of pediatric IBI in the post COVID-19 era.

The First Reported Case of Infant Botulism in Korea: Treatable Infantile Neuromuscular Disease.

Botulism is a rare neuromuscular disorder caused by neurotoxins produced by Clostridium botulinum. The diagnosis of infant botulism may be obscured or delayed, as its presentation is similar to that of infantile neuromuscular disorders. We report the first Korean case of infant botulism in an acute progressive floppy infant with poor sucking and a weak cry. No abnormalities were found in all blood, cerebrospinal fluid, genetic test, nerve conduction study, and imaging studies. A stool-toxin test was finally performed under suspicion of infant botulism, and the result was positive. The patient was immediately treated with heptavalent botulism antitoxin. Follow-up after 3 months showed normal development with a complete resolution of all symptoms. Therefore, clinical suspicion of infant botulism, which is a treatable infantile neuromuscular disease, is essential for early diagnosis and prompt treatment in the differential diagnosis of a floppy infant.

Improved Outcome of a Reduced Toxicity-Fludarabine, Cyclophosphamide, plus Antithymocyte Globulin Conditioning Regimen for Unrelated Donor Transplantation in Severe Aplastic Anemia: Comparison of 2 Multicenter Prospective Studies.

Hematopoietic stem cell transplantation (HSCT) is a curative therapy for severe aplastic anemia (SAA); however, the optimal conditioning regimen for HSCT with an unrelated donor has not yet been defined. A previous study using a fludarabine (FLU), cyclophosphamide (Cy), and antithymocyte globulin (ATG) conditioning regimen (study A: 50 mg/kg Cy once daily i.v. on days -9, -8, -7, and -6; 30 mg/m(2) FLU once daily i.v. on days -5, -4, -3, and -2; and 2.5 mg/kg of ATG once daily i.v. on days -3, -2, and -1) demonstrated successful engraftment (100%) but had a high treatment-related mortality rate (32.1%). Therefore, given that Cy is more toxic than FLU, we performed a new phase II prospective study with a reduced-toxicity regimen (study B: 60 mg/kg Cy once daily i.v. on days -8 and -7; 40 mg/m(2) FLU once daily i.v. on days -6, -5, -4, -3, and -2; and 2.5 mg/kg ATG once daily i.v. on 3 days). Fifty-seven patients were enrolled in studies A (n = 28) and B (n = 29), and donor type hematologic recovery was achieved in all patients in both studies. The overall survival (OS) and event-free survival (EFS) rates of patients in study B was markedly improved compared with those in study A (OS: 96.7% versus 67.9%, respectively, P = .004; EFS: 93.3% versus 64.3%, respectively, P = .008). These data show that a reduced-toxicity conditioning regimen with FLU, Cy, and ATG may be an optimal regimen for SAA patients receiving unrelated donor HSCT.

Risk Factors and Clinical Features of Cytomegalovirus Disease in Children Receiving Anticancer Chemotherapy.

This study was conducted to identify risk factors for cytomegalovirus (CMV) infection and demonstrate the spectrum of CMV disease in children receiving anticancer chemotherapy without hematopoietic stem cell transplantation (HSCT). A total of 289 children who received chemotherapy and were tested for CMV infection were included in the study. CMV antigenemia and DNAemia were determined by identifying the pp65 antigen in leukocytes and performing real-time PCR. CMV disease was diagnosed by tissue biopsy, culture, or ophthalmic examination. Of the 289 children, CMV infection was demonstrated in 46 patients (15.9%). Young age at cancer diagnosis was the risk factor for CMV infection by multivariate analysis (7 mo vs. 7 y, P<0.001). Among 46 children with CMV infection, 10 (21.7%) were diagnosed with CMV disease; hepatitis (n=4), retinitis (n=3), hepatitis and pneumonia (n=2), and hepatitis and retinitis (n=1). The age of the patients with CMV disease was significantly younger than those without (3 vs. 16 mo, P=0.023). Retinoblastoma and neuroblastoma were the 2 most common underlying malignancies. There were 2 fatal cases associated with CMV disease, including 1 who died of CMV pneumonia. The findings of this study demonstrated significant morbidity of CMV infection and disease in young children during the course of chemotherapy without HSCT.

The Risk of Acute Kidney Injury from Fluid Restriction and Hydroxyethyl Starch in Thoracic Surgery.

BACKGROUND: Fluid is restricted in thoracic surgery to reduce acute lung injury, and hydroxyethyl starches (HES) are often administered to reduce fluid amount. This strategy may contribute to the development of acute kidney injury (AKI). We evaluated the incidence, risk factors, and prognosis of AKI in thoracic surgery. We especially focused on whether fluid restriction/HES administration increased AKI. METHODS: This is a retrospective study of patients undergoing thoracic surgery in a tertiary care academic center. Postoperative AKI was diagnosed within 72 hours after surgery based on the Acute Kidney Injury Network criteria. Demographic, intraoperative, and postoperative data were compared between non-AKI and AKI groups. Logistic regression was used to model the association between risk factors and AKI. RESULTS: Final analysis included 1442 patients. Of these, 74 patients developed AKI (5.1%). Crystalloid restriction (≤3 mL·kg·h) was unrelated to AKI, regardless of preoperative renal functions (odds ratio [OR], 0.5; 95% confidence interval [CI] 0.2-1.4). AKI occurred more often when HES were administered to the patients with decreased renal function (OR, 7.6; 95% CI, 1.5-58.1) or having >2 risk factors with normal renal function (OR, 7.2; 95% CI, 3.6-14.1). Multivariate analysis revealed several risk factors: angiotensin-converting enzyme inhibitor/angiotensin receptor blockers, open thoracotomy, pneumonectomy/esophagectomy, diabetes mellitus, cerebrovascular disease, low albumin level, and decreased renal function. CONCLUSIONS: Fluid restriction neither increased nor was a risk factor for AKI. HES should be administered with caution in high-risk patients undergoing thoracic surgery.

Tracheal Intubation with a McGrath® Series 5 Video Laryngoscope by Novice Personnel in a Cervical-immobilized Manikin.

BACKGROUND: Prehospital tracheal intubation may be performed by novice intubators in cervical immobilized patients. However, most indirect laryngoscopes require special training. The McGrath® Series 5 video laryngoscope is similar to the Macintosh laryngoscope in shape and usage, yet still confers the advantages of having indirect laryngoscopes. OBJECTIVE: This study compared tracheal intubation by novice users, using the McGrath® Series 5 video laryngoscope vs. the Macintosh laryngoscope in a cervical immobilized manikin. METHODS: Thirty-eight nurses intubated the trachea of a manikin using a McGrath® Series 5 video laryngoscope and a Macintosh laryngoscope, in random order. Then they repeated the procedure in a manikin with a cervical collar. Success rate, time to success, number of intubation attempts, dental clicks, and difficulty score were compared between the two laryngoscopes. RESULTS: First-attempt success rate was higher for the McGrath® Series 5 compared to the Macintosh laryngoscope in cervical immobilizations (84.2% vs. 47.7%, respectively; p = 0.019). However, overall intubation success rate with and without the cervical collar was no different. Tracheal intubation using the McGrath® Series 5 was faster than the Macintosh laryngoscope regardless of the presence of a cervical collar. McGrath® Series 5 required fewer trials, had fewer dental clicks, and was easier to use than the Macintosh laryngoscope. CONCLUSIONS: McGrath® Series 5 video laryngoscope may be better than a standard Macintosh laryngoscope for novice intubators intubating the trachea in cervical immobilization, due to the higher first-attempt success rate, faster intubation time, fewer dental clicks, lower number of intubation attempts, and overall ease of use.

Calcium blockers decrease the bortezomib resistance in mantle cell lymphoma via manipulation of tissue transglutaminase activities.

Although bortezomib is clinically approved for the treatment of mantle cell lymphoma (MCL), only limited effects of this treatment have been demonstrated. To improve survival for bortezomib-resistant patients, it is necessary to develop new therapeutic strategies. In the present study, we used biochemical and molecular methodologies to demonstrate that tissue transglutaminase (TG) activates downstream NF-κB signaling pathways. The signaling axis from TG to NF-κB could be a new therapeutic target to overcome bortezomib resistance in MCL. TG2 is a calcium-dependent protein cross-linking enzyme reported to be overexpressed in various cancer cells. We found that MCL cells expressed elevated levels of TG2 and that the modification of TG2 activities altered NF-κB expression and downstream signaling in MCL cells. When TG2 signaling was inhibited by calcium blockers, the combination of a calcium blocker (perillyl alcohol) with bortezomib suppressed NF-κB expression and improved the cytotoxicity of bortezomib in MCL cells. Our study is the first to show the expression of TG2 and the contribution of TG2 to NF-κB signaling in MCL. TG2 inhibition may be used as an alternative target anti-MCL therapy, and calcium blockers may be combined with bortezomib to overcome the bortezomib resistance in MCL.

Stereoselective skin anti-photoaging properties of ginsenoside Rg3 in UV-B-irradiated keratinocytes.

Ginsenosides are major bioactive constituents that are responsible for the diverse pharmacological activities of ginseng. This work aimed to assess the skin anti-photoaging activities of the two stereoisomeric forms of ginsenoside Rg3, 20(S)-Rg3 and 20(R)-Rg3. When the two Rg3 stereoisomers were added to cultured human keratinocyte HaCaT cells prior to irradiation with 70 mJ/cm(2) UV-B, 20(S)-Rg3, but not 20(R)-Rg3, decreased the UV-B-induced intracellular reactive oxygen species (ROS) levels in a concentration-dependent manner, as detected by both fluorometric and confocal microscopic analyses. Likewise, 20(S)-Rg3, but not 20(R)-Rg3, decreased the UV-B-induced ROS levels in human dermal fibroblast cells. Both stereoisomers were unable to modulate the nitric oxide levels in HaCaT cells under UV-B irradiation, and induced no cytotoxicity in cultured keratinocytes and fibroblasts. 20(S)-Rg3 suppressed the UV-B-induced matrix metalloproteinase (MMP)-2 activities in HaCaT cells. Taken together, these results indicate that 20(S)-Rg3 possesses both ROS-scavenging and MMP-2 inhibitory activities, while 20(R)-Rg3 possesses neither activity. These findings imply that ginsenoside Rg3 stereoselectively demonstrates skin anti-photoaging activities.

Comparison of medical students' perceptions of patient safety: Focusing on simulation training using a high-fidelity simulator.

Patient safety education is necessary for the provision of high-quality medical services. A significant aspect of patient safety education is simulation training, which allows medical students to experience realistic clinical environments. This study aimed to verify the effectiveness of patient safety education using simulation training. We retrospectively analyzed the results of a 30-question questionnaire survey on the perceptions of patient safety before and after simulation training, which was completed by 40 medical students who participated in clinical practice between June and December 2021. A paired t-test was performed by calculating the mean and standard deviation for each item. We found that students' overall perceptions of patient safety improved after training. Specifically, after simulation training, attitudes toward patient safety were maintained at the same level as before training, while students' self-efficacy of patient safety increased. Simulation training is effective in improving students' perceptions of patient safety, and increasing students' confidence can improve their clinical performance. To maintain this effect, repeated learning is required, and theoretical classes and simulation training should be used appropriately for patient safety education in the future.

Pre-engraftment syndrome after unrelated cord blood transplantation: a predictor of engraftment and acute graft-versus-host disease.

Pre-engraftment syndrome (PES) is poorly characterized, and its clinical significance and the prognostic impact after unrelated cord blood transplantation (CBT) are unclear. To address these issues, we retrospectively analyzed the incidence, risk factors, and clinical outcomes of PES in unrelated CBT recipients. Data of 381 patients who received unrelated CBT from 18 medical centers in Korea were reviewed. PES was defined as unexplained fever >38.3°C not associated with infection, and/or unexplained skin rash with or without evidence of fluid retention before neutrophil recovery. PES developed in 102 patients (26.8%) at a median of 7 days after CBT. Of these patients, 74 patients (72.5%) received intravenous corticosteroid at a median dose of 1 mg/kg/day, and of these, 95% showed clinical improvement. Risk factors for developing PES included low risk disease, myeloablative conditioning, graft-versus-host disease (GVHD) prophylaxis without methotrexate or corticosteroid, and >5.43 x 10(7)/kg infused nucleated cells. Absence of PES was one of the risk factors for graft failure in multivariate analysis. The cumulative incidence of grade II to grade IV acute GVHD by 100 days after CBT was higher in patients with PES than in those without PES (56.0% versus 34.4%, P < .01). PES was not associated with chronic GVHD, treatment-related mortality, relapse, or overall survival. PES seems to be common after CBT and may be associated with enhanced engraftment without significant morbidity.

Antioxidative, anti-inflammatory, and matrix metalloproteinase inhibitory activities of 20(S)-ginsenoside Rg3 in cultured mammalian cell lines.

Ginsenoside Rg3 is one of ginsenosides that are the well-known bioactive principles of Panax ginseng. Among the two stereoisomeric forms of Rg3, 20(S)-ginsenoside Rg3 [20(S)-Rg3] is predominant. 20(S)-Rg3 is capable of suppressing the nitric oxide (NO), reactive oxygen species (ROS) and prostaglandin E2 (PGE2) productions induced by lipopolysaccharide (LPS) in RAW264.7 macrophage cells in a concentration-dependent manner. In the same stimulated macrophages, 20(S)-Rg3 was able to suppress matrix metalloproteinase-9 (MMP-9) activity and suppress cyclooxygenase-2 (COX-2) expression. It suppressed the production of some proinflammatory cytokines, such as TNF-α, IL-1ß and IL-6, and the cell mobility enhanced by LPS in the macrophage cells. 20(S)-Rg3 displayed suppressive effect on the ROS level but not on the NO level, and down-regulating effect on MMP-9 but not on MMP-2 in non-stimulated HaCat keratinocytes. 20(S)-Rg3 also exhibited suppressive effect on the MMP-9 gelatinolytic activity enhanced in the HaCat keratinocytes stimulated with tumor necrosis factor-α (TNF-α), one of the major proinflammatory cytokines. However, 20(S)-Rg3 was not able to modulate the NO level even in the presence of TNF-α. Taken together, anti-inflammatory and related antioxidative and MMP-9 inhibitory activities of 20(S)-Rg3, the major stereoisomeric form of ginsenoside Rg3, are confirmed in macrophage and keratinocyte cell lines.

Reactive oxygen species-dependent down-regulation of tumor suppressor genes PTEN, USP28, DRAM, TIGAR, and CYLD under oxidative stress.

We examined whether steady-state mRNA levels of five tumor suppressor genes are subjected to oxidative stress. Superoxide radical-generating menadione and serum deprivation diminished the steady-state mRNA levels for the genes phosphatase and tensin homolog (PTEN), ubiquitin specific peptidase 28 (USP28), damage-regulated autophagy modulator (DRAM), TP53-induced glycolysis and apoptosis regulator (TIGAR), and cylindromatosis (CYLD). Hydrogen peroxide showed suppression in steady-state mRNA levels for USP28, DRAM, TIGAR, and CYLD but not for PTEN. The steady-state mRNA levels specific for all five genes were enhanced by antioxidants, such as glutathione and N-acetylcysteine. The HepG2 stable transfectants overexpressing the mitochondrial isoform of human glutaredoxin, Grx2a, and containing a relatively low reactive oxygen species (ROS) level were assessed to contain the increased steady-state mRNA levels specific for the five tumor suppressor genes. In brief, the steady-state mRNA levels specific for these genes are negatively regulated by oxidative stress through the mediation of ROS.

Changes in the Incidence of Immune Thrombocytopenia in the Coronavirus Disease 2019 Era: A Nationwide Observational Study in Korea.

Purpose: We investigated whether nonpharmaceutical interventions (NPI) to reduce the spread of coronavirus disease 2019 (COVID-19) was associated with a change in the incidence of immune thrombocytopenia (ITP). Patients and Methods: Using the Korean Health Insurance Review and Assessment Services (HIRA) database, individuals newly diagnosed with ITP between January 2015 and December 2020 were identified. The NPI period was defined as February 2020 to December 2020. The ITP incidence in the NPI period was compared with the mean annual incidence during the same months in the pre-NPI period and the incidence predicted by the autoregressive integrated moving average model. Results: In total, 25,723 patients were identified, and the overall annual incidence of ITP was 8.28 per 100,000 persons ([95% confidence interval (CI): 8.18-8.39]. The ITP incidence in the NPI period was 6.60 per 100,000 person-years (95% CI: 6.37-6.85), 0.77 times (95% CI: 0.74-0.80) lower than that during the pre-NPI period [8.62/100,000 (95% CI: 8.50-8.74)]. With the exception for patients aged ≥70 years, the ITP incidence was significantly lower in the NPI period than in the pre-NPI period. The most significant decline in the ITP incidence during the NPI period was observed in the 0-9 years age group [25.76/100,000 vs 14.01/100,000, P <0.001; incidence rate ratio (IRR): 0.54 (95% CI: 0.51-0.58)]. The intravenous immunoglobulin-treated ITP incidence in the NPI period was 1.69/100,000 (95% CI: 1.58-1.81), 0.79 times (95% CI: 0.73-0.85) lower than that in the pre-NPI period 2.15/100,000 (95% CI: 2.09-2.21)]. The incidence of steroid-treated ITP was lower in the NPI period than in the pre-NPI period (2.73/100,000 vs 2.2/100,000, P <0.001), with an IRR of 0.80 (95% CI: 0.76-0.83). Conclusion: This nationwide study revealed a significant decrease in ITP incidence, particularly among children, after the implementation of NPI.

Synergistic anticancer effects of arsenic trioxide with bortezomib in mantle cell lymphoma.

Mantle cell lymphoma (MCL) is a subtype of B-cell Non-Hodgkin's Lymphoma (NHL) and accounts for ~6% of all lymphomas. MCL is highly refractory to most chemotherapy including newer antibody-based therapeutic approaches, and high-grade MCL has one of the worst survival rates among NHLs. Therefore, the development of new therapeutic strategies to overcome drug resistance of MCL is important. In this article, we tested the effects of arsenic trioxide (As(2) O(3) , ATO) in bortezomib-resistant MCL. ATO is reported to induce complete remission in the patients with relapsed or refractory acute promyelocytic leukemia. Their effects in MCL, however, have not been explored. In this report, we show that ATO effectively inhibited the growth of MCL cells in vitro. ATO treatment also reduced cyclin D1 expression which is a genetic hallmark of MCL and NF-kB expression which was reported to have a prosurvival role in some MCL cells. The induction of apoptosis in MCL was partially due to reduced levels of cyclin D1 and increased levels of apoptosis-related molecules. The antiproliferative effects of bortezomib on MCL greatly increased when the cells were also treated with ATO, indicating ATO can sensitize MCL to bortezomib. Similar results were noted in bortezomib-resistant cell lines. In conclusion, ATO may be an alternative drug for use in combined adjuvant therapies for MCL, and further clinical testing should be performed.

Glutaredoxin 2a, a mitochondrial isoform, plays a protective role in a human cell line under serum deprivation.

The roles of mitochondrial glutaredoxin (Grx2a) under serum deprivation were assessed using the human stable HepG2 cell lines overexpressing or down-regulating Grx2a. The Grx2a-overexpressing stable cells displayed enhanced proliferation, decreased reactive oxygen species (ROS) and caspase-3 activity levels, and increased total GSH level, compared to the vector control cells. These characteristics of the overexpressing stable cells were reversed by down-regulating Grx2a in the same cell line. In the limited serum conditions, the Grx2a-overexpressing stable pcDNA3.0/HA-Grx2a cells exhibited higher cellular viabilities and total GSH level, and showed much lower enhancement in ROS and caspase-3 activity levels than the vector control pcDNA3.0/HA cells. However, the Grx2a-down-regulating stable cells gave rise to diminished cellular viabilities and further decreased total GSH level, and contained significantly higher ROS and caspase-3 activity levels, under serum deprivation than the vector control cells. These results suggest that Grx2a plays proliferative and anti-apoptotic roles under serum deprivation.

Anti-inflammatory, antinociceptive and anti-angiogenic activities of a phospholipid mixture purified from porcine lung tissues.

This work aimed to assess anti-inflammatory and related properties of a phospholipid mixture purified from porcine lung tissues, named KT&G101, which is being developed as a novel topical remedy for atopic dermatitis. KT&G101 consists of pure phospholipids, mainly phosphatidylcholine (PC) and other phospholipids such as phosphatidylinositol (PI) and phosphatidylserine (PS). Its predominant PC species is 1,2-dipalmitoylphosphatidylcholine (DPPC). KT&G101 exhibited an anti-angiogenic activity in the chick chorioallantoic membrane (CAM) assay. Oral administration of KT&G101 at the dosages of 100, 200 and 400 mg/kg body weight gave rise to an inhibition of 15.4%, 25.3% and 30.1% in the vascular permeability assay, respectively. In the carrageenan-induced inflammation in the air pouches, KT&G101 significantly diminished the volume of exudates in the pouches, the number of polymorphonuclear leukocytes and nitrite content in exudates. In the acetic acid-induced writhing response, oral administration of KT&G101 at the dosages of 50, 100 and 200 mg/kg body weight showed the reduction of 21.6%, 51.6% and 60.8% in the pain response of mice, respectively. It was also able to diminish the nitric oxide (NO) and reactive oxygen species (ROS) levels in the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. KT&G101 displayed a significant suppression on the induction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in the stimulated RAW264.7 cells. However, the free radical scavenging activity of KT&G101 was detected to be very weak in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Taken together, KT&G101 possesses anti-inflammatory and related antinociceptive and anti-angiogenic activities, which indirectly supports its use as an anti-atopic therapy.

Effect of a Regional Outbreak of Coronavirus Disease 2019 on Kawasaki Disease in Korea.

Purpose: The association between coronavirus disease 2019 (COVID-19) and Kawasaki disease (KD) remains controversial. Prior to the nationwide epidemic of COVID-19, there was a unique, large-scale, regional outbreak in Daegu and Gyeonsangbuk-do (DG) in Korea in the spring of 2020. We evaluated the impact of COVID-19 on KD by comparing the characteristics of KD incidence between epidemic and non-epidemic regions in Korea. Patients and Methods: We analyzed nationwide Health Insurance Review and Assessment (HIRA) data to estimate KD incidence from February 2019 to July 2020. Patients below 18 years who were admitted with KD and administered both intravenous immunoglobulin and aspirin (ICD-10 code M303 for KD) were included in the study. We compared the incidence of KD in DG and other regions by analyzing the period-specific incidence from February to May before and after the COVID-19 era. Results: A total of 4461 patients were identified to have KD nationwide from February 2019 to July 2020. The nationwide incidence of KD was significantly reduced during this period compared with the period from February 2018 to July 2019 (p < 0.001). In the DG region, within the 0-4-years age group, there was no significant difference in the incidence of KD between periods (p = 0.714). In the 5-9 years age group, a significant decrease in KD incidence was observed in the DG region and all other regions from February 2019 to July 2020. Conclusion: There was a significant decrease in nationwide KD incidence during and until 2 months after the local epidemic in Korea. However, no significant decrease in KD incidence was observed in the 0-4 years age group in the DG region where the local COVID-19 outbreak occurred. A larger study is necessary to determine the correlation between KD in this age group and the COVID-19 outbreak.

Changes in Etiology of Invasive Bacterial Infections in Infants Under 3 Months of Age in Korea, 2006-2020.

OBJECTIVES: Invasive bacterial infection (IBI) causes a significant burden in infants. In this study, we analyzed changes in epidemiology of IBI among infants in Korea. METHODS: A retrospective multicenter-based surveillance for IBIs in infants <3 months of age was performed during 2006-2020. Cases were classified as an early-onset disease (EOD) (0-6 days) or late-onset disease (LOD) (7-89 days). The temporal trend change in proportion of pathogens was analyzed. RESULTS: Among 1545 cases, the median age was 28 days (IQR: 12, 53) and EOD accounted for 17.7%. Among pathogens, S. agalactiae (40.4%), E. coli (38.5%), and S. aureus (17.8%) were the most common and attributed for 96.7%. Among EOD (n = 274), S. agalactiae (45.6%), S. aureus (31.4%), E. coli (17.2%) and L. monocytogenes (2.9%) were most common. Among LOD (n = 1274), E. coli (43.1%), S. agalactiae (39.3%), S. aureus (14.9%) and S. pneumoniae (1.3%) were most common. In the trend analysis, the proportion of S. aureus (r s = -0.850, P < 0.01) decreased significantly, while that of S. agalactiae increased (r s = 0.781, P < 0.01). CONCLUSION: During 2006-2020, among IBI in infants <3 months of age, S. agalactiae, E. coli, and S. aureus were most common and an increasing trend of S. agalactiae was observed.

Current status of pediatric umbilical cord blood transplantation in Korea: a multicenter retrospective analysis of 236 cases.

We report the outcome of 236 pediatric umbilical cord blood transplantations (UCBT) performed in Korea. Given that the sources of the grafts were mostly unrelated donors (n = 226; 95.8%), only the results of unrelated UCBT were included for all statistics. The most frequent primary disease was acute leukemia (n = 167). In total, 91.7% of recipients were seropositive for cytomegalovirus (CMV). The median doses of nucleated cells and CD34+ cells were 4.84 × 10(7)/kg and 2.00 × 10(5)/kg, respectively. The median times to neutrophil (>0.5 × 10(9)/L) and platelet recovery (>20 × 10(9)/L) were 18 and 45 days, respectively. Grade 2-4 acute graft-versus-host-disease (GVHD) and chronic GVHD developed in 41.1 and 36.1% of cases, respectively. Forty-five patients developed CMV disease. The 5-year overall and event-free survival were 47.5 and 36.9%, respectively. Multivariate analysis revealed that adverse factors for survival of the whole cohort were total body irradiation-based conditioning (P = 0.007), salvage transplant (P = 0.001), failure to achieve early complete chimerism (P < 0.0005), and CMV disease (P = 0.001). The outcomes of the single- and double-unit UCBT (n = 64) were similar, while double-unit recipients were heavier (P < 0.0005) and older (P < 0.0005). We conclude that double-unit UCBT is a reasonable option for older or heavier children and that the thorough surveillance of CMV infection and the development of an effective CMV therapeutic strategy may be especially important for Korean children, whose CMV seroprevalence exceeds 90%.