Associations between short-term exposure to air pollution and thyroid function in a representative sample of the Korean population.

BACKGROUND: Disruption of thyroid function can profoundly affect various organ systems. However, studies on the association between air pollution and thyroid function are relatively scarce and most studies have focused on the long-term effects of air pollution among pregnant women. OBJECTIVES: This study aimed to explore the associations between short-term exposure to air pollution and thyroid function in the general population. METHODS: Data from the Korea National Health and Nutrition Examination Survey (2013-2015) were analyzed (n = 5,626). Air pollution concentrations in residential addresses were estimated using Community Multiscale Air Quality models. The moving averages of air pollution over 7 days were set as exposure variables through exploratory analyses. Linear regression and quantile g-computation models were constructed to assess the effects of individual air pollutants and air pollution mixture, respectively. RESULTS: A 10-ppb increase in NO2 (18.8-µg/m3 increase) and CO (11.5-µg/m3 increase) was associated with 2.43% [95% confidence interval (CI): 0.42, 4.48] and 0.19% (95% CI: 0.01, 0.36) higher thyroid-stimulating hormone (TSH) levels, respectively. A 10-µg/m3 increase in PM2.5 and a 10-ppb increase in O3 (19.6-µg/m3 increment) were associated with 0.87% (95% CI: 1.47, -0.27) and 0.59% (95% CI: 1.18, -0.001) lower free thyroxine (fT4) levels, respectively. A simultaneous quartile increase in PM2.5, NO2, O3, and CO levels was associated with lower fT4 but not TSH levels. CONCLUSIONS: As the subtle changes in thyroid function can affect various organ systems, the present results may have substantial public health implications despite the relatively modest effect sizes. Because this was a cross-sectional study, it is necessary to conduct further experimental or repeated-measures studies to consolidate the current results.

Prolonged Union in Conservative Treatment of Symphalangeal Toe Fractures: Case Series.

Background: Toe symphalangism is characterized by a fusion of the interphalangeal joint between the middle and distal phalanges. While typical lesser toe fractures heal well with conservative treatment, in our clinical experience, we encountered patients with symphalangeal toe fractures who experienced long-lasting pain and delayed radiographic union. Therefore, this study aimed to report radiographic outcomes following conservative treatment of symphalangeal fractures of the lesser toes. Methods: We retrospectively reviewed 14 patients with symphalangeal lesser toe fractures who were treated conservatively. We investigated the mechanism of injury and measured the time from the initial injury date to the complete radiographic union. The fracture gap distance was measured on an initial lateral radiograph. Results: Symphalangeal fractures involved the fourth toe in 4 patients (28.5%) and the fifth toe in 10 patients (71.4%). Regarding the mechanism of injury, 6 patients (42.9%) were injured by stubbing or bumping into the door, 5 patients (35.7%) were injured by tripping, 2 patients (14.3%) were injured by heavy objects falling directly on their toes, and 1 patient (2.3%) complained of pain after wearing pointed shoes for half a day. The mean time to complete union was 9.1 months, and the median period was 5.5 months (range, 0.8-29 months). The initial gap of the fracture was 0.60 mm (range, 0.30-1.04 mm). Conclusions: The results of our case series may help counsel patients in the outpatient clinic that prolonged healing time may be required for the union of symphalangeal toe fractures.

Clinical outcomes following tibiotalocalcaneal arthrodesis with intramedullary nailing combined with partial fibulectomy and onlay bone graft.

INTRODUCTION: Although intramedullary nailing is a popular method for tibiotalocalcaneal arthrodesis, nonunion is one of the most commonly reported complications. This study aimed to evaluate the fusion rate, improvement in functional outcomes, and occurrence of complications in tibiotalocalcaneal arthrodesis using retrograde intramedullary nailing with partial fibulectomy and onlay bone graft technique. MATERIALS AND METHODS: Twenty-six consecutive patients using the proposed technique were retrospectively reviewed. For radiographic outcomes, the union rate, alignment, and any related complications were assessed. Functional outcomes were evaluated using the American Orthopedic Foot and Ankle Society hindfoot scale, Foot and Ankle Outcome Score, and visual analog scale, preoperatively and at the final follow-up. RESULTS: The mean follow-up period was 38.2 months. The tibiotalar joint achieved complete union in 80.8% at six months postoperatively, while all the cases achieved complete union at 12 months postoperatively. However, the subtalar joint achieved complete union in 26.9% at six months postoperatively, which gradually increased to 73.1% at 12 months postoperatively, and 80.8% at the final follow-up without revision surgery. A subgroup analysis showed there was a trend of higher subtalar fusion rate when an additional screw for the subtalar joint fixation was placed (86.7% vs. 54.5%). The functional outcomes significantly improved at the final follow-up. A few minor complications occurred, including surgical site infection, irritational symptoms, and metal failure; however, they eventually resolved. CONCLUSIONS: Our technique of tibiotalocalcaneal arthrodesis with partial fibulectomy and onlay bone grafting could be a good option where both the tibiotalar and subtalar joints need to be fused.

Efficacy of Far Cortical Locking Screws in Treating Distal Tibia Fractures in Comparison With That of Standard Locking Screws.

There are no clinical studies about treatment of distal tibia fractures using far cortical locking (FCL) screws, even though it has been shown to be superior to standard locking screws in biomechanical studies. We compared the efficacy of FCL screws to that of traditional locking screws. Twenty-five distal tibia fractures were treated with minimally invasive plate osteosynthesis using traditional locking screws, whereas 20 were treated using FCL screws. We retrospectively compared time taken for callus formation and radiographic bone union between 2 groups. The effect of age, sex, diabetes, and smoking history on bone healing was analyzed. Complications were also noted. As a result, there was no significant difference in age (p = .292), sex (p = 1.0), diabetes (p = 1.0), or smoking history (p = .704) between 2 groups. Time to callus formation was 77.5 days in the FCL group, and 96 days in the traditional group (p = .023). Average time to bone union was 134.8 days, and 163.1 days in the FCL group and the traditional group, respectively (p = .017). There was one case of screw loosening in the FCL group, and one case of screw breakage in the traditional group. This study suggests that FCL screws promote quicker healing of distal tibia fractures than traditional locking screws.

Foot and Ankle Motion after Tibiotalocalcaneal Arthrodesis: Comparison with Tibiotalar Arthrodesis Using a Multi-Segment Foot Model.

Background: Tibiotalocalcaneal arthrodesis is an established surgical procedure for treating patients with end-stage ankle joint arthritis and subtalar joint arthritis. Although it greatly relives pain, a major drawback is loss of range of motion. Although it is known to restrict an additional subtalar joint compared to tibiotalar arthrodesis, there is a lack of gait analysis studies comparing the two methods. This study aimed to evaluate the differences in kinematics of the foot and ankle joints between tibiotalar and tibiotalocalcaneal arthrodesis. We also compared preoperative and postoperative statuses for each surgical method. Methods: The study included 12 and 9 patients who underwent tibiotalar and tibiotalocalcaneal arthrodesis, respectively, and 40 healthy participants were included in the control group. The DuPont foot model was used to analyze intersegmental foot and ankle kinematics during gait. Results: Compared to controls, both tibiotalar and tibiotalocalcaneal arthrodesis resulted in slow gait speed with reduced stride length, increased step width, and decreased range of sagittal plane motion. Both fusion methods showed similar range of motion in all segments and planes following surgery. Coronal positions showed more supination of the forefoot and pronation of the hindfoot segment after each operation, particularly tibiotalocalcaneal arthrodesis. Gait after tibiotalocalcaneal arthrodesis did not significantly differ from that after tibiotalar arthrodesis, but there was a tendency of more pronation in the hindfoot segment. Conclusions: Both fusion methods limited foot and ankle motion in similar ways. Comparing tibiotalar and tibiotalocalcaneal arthrodesis suggests that additionally fusing the subtalar joint does not cause greater movement restriction in patients. Objectively comparing tibiotalar and tibiotalocalcaneal arthrodesis will facilitate further understanding of the effect of tibiotalocalcaneal arthrodesis on movement and the value of subtalar joint motion for improved preoperative counselling.

Whole-genome sequencing and genetic diversity of severe fever with thrombocytopenia syndrome virus using multiplex PCR-based nanopore sequencing, Republic of Korea.

BACKGROUND: Whole-genome sequencing plays a critical role in the genomic epidemiology intended to improve understanding the spread of emerging viruses. Dabie bandavirus, causing severe fever with thrombocytopenia syndrome (SFTS), is a zoonotic tick-borne virus that poses a significant public health threat. We aimed to evaluate a novel amplicon-based nanopore sequencing tool to obtain whole-genome sequences of Dabie bandavirus, also known as SFTS virus (SFTSV), and investigate the molecular prevalence in wild ticks, Republic of Korea (ROK). PRINCIPAL FINDINGS: A total of 6,593 ticks were collected from Gyeonggi and Gangwon Provinces, ROK in 2019 and 2020. Quantitative polymerase chain reaction revealed the presence of SFSTV RNA in three Haemaphysalis longicornis ticks. Two SFTSV strains were isolated from H. longicornis captured from Pocheon and Cheorwon. Multiplex polymerase chain reaction-based nanopore sequencing provided nearly full-length tripartite genome sequences of SFTSV within one hour running. Phylogenetic and reassortment analyses were performed to infer evolutionary relationships among SFTSVs. Phylogenetic analysis grouped SFTSV Hl19-31-4 and Hl19-31-13 from Pocheon with sub-genotype B-1 in all segments. SFTSV Hl20-8 was found to be a genomic organization compatible with B-1 (for L segment) and B-2 (for M and S segments) sub-genotypes, indicating a natural reassortment between sub-genotypes. CONCLUSION/SIGNIFICANCE: Amplicon-based next-generation sequencing is a robust tool for whole-genome sequencing of SFTSV using the nanopore platform. The molecular prevalence and geographical distribution of SFTSV enhanced the phylogeographic map at high resolution for sophisticated prevention of emerging SFTS in endemic areas. Our findings provide important insights into the rapid whole-genome sequencing and genetic diversity for the genome-based diagnosis of SFTSV in the endemic outbreak.

A Portable Diagnostic Assay, Genetic Diversity, and Isolation of Seoul Virus from Rattus norvegicus Collected in Gangwon Province, Republic of Korea.

Seoul virus (SEOV), an etiological agent for hemorrhagic fever with renal syndrome, poses a significant public health threat worldwide. This study evaluated the feasibility of a mobile Biomeme platform for facilitating rapid decision making of SEOV infection. A total of 27 Rattus norvegicus were collected from Seoul Metropolitan City and Gangwon Province in Republic of Korea (ROK), during 2016-2020. The serological and molecular prevalence of SEOV was 5/27 (18.5%) and 2/27 (7.4%), respectively. SEOV RNA was detected in multiple tissues of rodents using the Biomeme device, with differences in Ct values ranging from 0.6 to 2.1 cycles compared to a laboratory benchtop system. Using amplicon-based next-generation sequencing, whole-genome sequences of SEOV were acquired from lung tissues of Rn18-1 and Rn19-5 collected in Gangwon Province. Phylogenetic analysis showed a phylogeographical diversity of rat-borne orthohantavirus collected in Gangwon Province. We report a novel isolate of SEOV Rn19-5 from Gangwon Province. Our findings demonstrated that the Biomeme system can be applied for the molecular diagnosis of SEOV comparably to the laboratory-based platform. Whole-genome sequencing of SEOV revealed the phylogeographical diversity of orthohantavirus in the ROK. This study provides important insights into the field-deployable diagnostic assays and genetic diversity of orthohantaviruses for the rapid response to hantaviral outbreaks in the ROK.

Long-term exposure to air pollution and the blood lipid levels of healthy young men.

BACKGROUND: There is insufficient evidence of an association between long-term exposure to air pollution and changes in blood lipid levels, and assessments may be influenced by residual confounding factors, such as socioeconomic status. OBJECTIVES: To investigate the associations between long-term exposure to air pollution and blood lipid profiles while controlling for the risk of residual confounding factors. METHODS: We conducted a study involving conscripted Korean soldiers to assess the associations between air pollution and blood lipid levels. The soldiers, who were randomly distributed among military units throughout the country, led homogenous lives and were subjected to health checkups 8-12 months post-enlistment. We analyzed data pertaining to those who enlisted and underwent health checkups in 2019 (n = 12,778) using linear mixed models. Additionally, we evaluated quantile-specific associations using quantile regression models. We also assessed interactions based on body mass index (BMI) at the time of enlistment (≥25.0 vs. < 25.0 kg/m2). RESULTS: The linear mixed models revealed that a 10-µg/m3 increase in fine particulate matter ≤ 2.5 µm (PM2.5) decreased high-density lipoprotein cholesterol (HDL-C) levels by -0.66% (95% confidence interval [CI]: -1.21, -0.10), and a 10-ppb increase in nitrogen dioxide (NO2) increased total cholesterol (TC) levels by 1.04% (95% CI: 0.24, 1.84). In the quantile regression models, associations were also found at specific deciles. PM2.5 exposure contributed to higher TC, NO2 resulted in higher triglycerides and lower HDL-C, and ozone (O3) led to lower HDL-C. The association between O3 and TC differed according to BMI (p-value for interaction = 0.03); among those with a BMI ≥ 25.0 kg/m2, a 10-ppb increase in O3 increased TC by 1.09% (95% CI: 0.20, 1.09). DISCUSSION: These results shed new light on the importance of controlling air pollution, which can contribute to abnormal blood lipid levels, an independent risk factor for cardiovascular disease.

Effects of preoperative, scheduled administration of antiemetics in reducing postoperative nausea and vomiting in patients undergoing total knee arthroplasty.

ABSTRACT: There is no established protocol regarding the timing of administration of antiemetics in patients undergoing total knee arthroplasty (TKA). The purpose of this study was to determine whether preoperative, rather than postoperative administration of an antiemetic could reduce postoperative nausea and vomiting (PONV) in patients undergoing TKA, and whether there was a difference in postoperative pain, patient satisfaction and complications after TKA between the 2 different administration times.The included patients (N = 101) either received intravenous administration of the ramosetron 1 hour before surgery (N = 50) or at the end of surgery (N = 51) consecutively order. The incidence of PONV and the frequency of rescue medicine use were recorded until 48 hours postoperatively. The severity of postoperative pain and patient satisfaction were assessed using the visual analogue scale. The incidence of complications associated with use of antiemetic was assessed.Preoperative administration of ramosetron did not decrease PONV during the first 48 hours. There was no significant difference in the incidence of nausea and vomiting, use of rescue antiemetics, and the severity of nausea (P > .05). Postoperative pain, satisfaction scores, and the incidence of complications were not different between the 2 groups (P > .05).Preoperative administration of ramosetron did not show clinical advantage in reducing POVN, postoperative pain and improving patient satisfaction. However, the outcomes of complications were not inferior to those of postoperative administration. Therefore, under the current protocol of multimodal therapies, timing of administration of pre-emptive antiemetic did not have significant effect on PONV.

Association between short-term air pollution exposure and attention-deficit/hyperactivity disorder-related hospital admissions among adolescents: A nationwide time-series study.

Long-term air pollution exposure has been suggested to increase the risk of attention-deficit/hyperactivity disorder (ADHD). However, the association between short-term air pollution exposure and ADHD-related outcomes is still unknown. We investigated the associations between short-term exposure to particulate matter with an aerodynamic diameter ≤10 µm (PM10), nitrogen oxide (NO2), and sulfur dioxide (SO2) and hospital admissions with a principal diagnosis of ADHD among adolescents (age 10-19 years) in 16 regions of the Republic of Korea from 2013 to 2015. We estimated the region-specific relative risks (RRs) and 95% confidence intervals (CIs) from quasi-Poisson regressions adjusted for potential confounders, considering single-day and moving average lag. Consequently, we performed meta-analyses to pool the region-specific estimates. The risks of ADHD-related hospital admissions were increased in the single-day and moving average lag models for PM10 (largest association for lag 1 in the single-day lag model, RR = 1.12, 95% CI: 1.05, 1.20; lag 0-2 in the moving average lag model, RR = 1.17, 95% CI: 1.07, 1.27), NO2 (lag 3, RR = 1.47, 95% CI: 1.25, 1.73; lag 1-3, RR = 1.68, 95% CI: 1.38, 2.04), and SO2 (lag 1, RR = 1.27, 95% CI: 1.14, 1.41; lag 1-3, RR = 1.29, 95% CI: 1.12, 1.49). The associations were similar between boys and girls, but they were stronger among adolescents aged 15-19 years than those aged 10-14 years for NO2 and SO2. In conclusion, the results indicate that short-term exposure to PM10, NO2, and SO2 may be a risk factor for the exacerbation of ADHD symptoms, leading to hospitalization.

Posterior condylar offset changes and its effect on clinical outcomes after posterior-substituting, fixed-bearing total knee arthroplasty: anterior versus posterior referencing.

BACKGROUND: We sought to determine whether there was a difference in the posterior condylar offset (PCO), posterior condylar offset ratio (PCOR) and clinical outcomes following total knee arthroplasty (TKA) with anterior referencing (AR) or posterior referencing (PR) systems. We also assessed whether the PCO and PCOR changes, as well as patient factors were related to range of motion (ROM) in each referencing system. METHODS: This retrospective study included 130 consecutive patients (184 knees) with osteoarthritis who underwent primary posterior cruciate ligament (PCL)-substituting fixed-bearing TKA. The difference between preoperative and postoperative PCO and PCOR values were calculated. Clinical outcomes including ROM and Western Ontario and McMaster University (WOMAC) scores were evaluated. Furthermore, multiple linear regression analysis was performed to determine the factors related to postoperative ROM in each referencing system. RESULTS: The postoperative PCO was greater in the AR group (28.4 mm) than in the PR group (27.4 mm), whereas the PCO was more consistently preserved in the PR group. The mean postoperative ROM after TKA was greater in the AR group (129°) than in the PR group (122°), whereas improvement in WOMAC score did not differ between the two groups. Preoperative ROM was the only factor related to postoperative ROM in both groups. CONCLUSIONS: There was no difference in postoperative PCO in AR and PR group and the PCO was not associated with postoperative ROM. PCO was more consistently preserved after surgery in the PR group. The postoperative PCO and PCOR changes did not affect the postoperative ROM. Furthermore, similar clinical outcomes were achieved in the AR and PR groups. TRIAL REGISTRATION: Retrospectively registered (Trial registration number: 06-2010-110).

Febrile Respiratory Illness Associated with Human Adenovirus Type 55 in South Korea Military, 2014-2016

An outbreak of febrile respiratory illness associated with human adenovirus (HAdV) occurred in the South Korea military during the 2014-15 influenza season and thereafter. Molecular typing and phylogenetic analysis of patient samples identified HAdV type 55 as the causative agent. Emergence of this novel HAdV necessitates continued surveillance in military and civilian populations.

Complete Genome Sequence of Human Adenovirus Type 55 Associated with Acute Respiratory Disease, Isolated from a Military Base in the Republic of Korea.

Human adenovirus (HAdV) (genus Mastadenovirus; family Adenoviridae) serotype 55 is a reemerging pathogen associated with acute respiratory disease. Here, we report the complete genome sequence of HAdV-55 strain AFMC 16-0011, isolated from a military recruit, using next-generation sequencing technology.

Prevalence of electrocardiographic findings suggestive of sudden cardiac death risk in 10,867 apparently healthy young Korean men.

BACKGROUND: The objective of this study was to determine the prevalence of electrocardiographic (ECG) findings suggestive of sudden cardiac death risk in apparently healthy young Korean men. METHODS: We administered questionnaires that elicited personal and family histories and performed ECGs on 10,867 male subjects (mean age, 20.9 years). The subjects with abnormal ECG findings underwent echocardiography, a treadmill test, Holter monitoring, a flecainide provocation test, or an electrophysiologic study (EPS) according to the ECG findings and histories. RESULTS: Of the subjects, 5.95% had left ventricular hypertrophy on ECG, but no subjects had hypertrophic cardiomyopathy by echocardiography. The percentage of subjects with a Brugada ECG pattern was 0.90%. We identified one subject with a positive result on the flecainide provocation test. The percentage of subjects with a preexcitation ECG was 0.17%. In two of the subjects, supraventricular tachycardia was induced in the EPS. Of the subjects, 0.05% had epsilon waves, but there were no subjects with arrhythmogenic right ventricular dysplasia/cardiomyopathy by echocardiography. The percentage of subjects with long QT intervals was 0.02%, but there were no arrhythmias on the treadmill test or Holter monitoring. CONCLUSIONS: The prevalence of a Brugada ECG pattern in apparently healthy young men is higher in Korea than other countries.