Innovative building materials by upcycling clothing waste into thermal energy storage matrix with phase change materials.

The current volume of clothing waste reached 115 million tons in 2021 and is projected to increase to approximately 150 million tons by 2030. This significant surge in clothing waste has prompted heightened discussions regarding environmentally friendly recycling methods. Clothing presents complex properties, posing substantial challenges to recycling and usually resulting in environmental pollution when disposed. In this study, our recycling approach capitalizes on the differing melting points of textiles. This transformation was achieved through a physical process that included an opening procedure and high temperature heat compression. Textile materials exhibit exceptional thermal properties. Through experimentation on 50 g fiber specimens, thermal conductivities similar to commercial insulation materials were observed, registering an average of 0.0592 W/m·K at 20 °C and 0.06053 W/m·K at 40 °C. This study explores the impregnation of phase change materials (PCMs) into clothing waste-based specimens, equipping them with heat storage capabilities. During the experimental phase, we employed three distinct types of PCMs to evaluate their thermal properties and heat storage capacities in relation to their respective melting temperatures. Through thermal properties analysis, we determined the latent heat capacity of each specimen, ranging from a minimum of 6.63 J/g to a maximum of 75.81 J/g. Our observations indicated a reduction in peak temperature and time-leg effects attributable to the use of PCMs for surface heat flow. This research underscores the superior thermal performance of construction and building materials derived from clothing waste, enhanced by the integration of PCMs, when compared to traditional materials and other waste-derived alternatives.

Effects of 4-hexylresorcinol on facial skeletal development in growing rats: Considerations for diabetes / 대한치과교정학회지

Objective@#To investigate the long-term effects of 4-hexylresorcinol (4HR) on facial skeletal growth in growing male rats, with a focus on diabetic animal models. Methods: Forty male rats were used. Of them, type 1 diabetes mellitus was induced in 20 animals by administering 40 mg/kg streptozotocin (STZ), and they were assigned to either the STZ or 4HR-injected group (STZ/4HR group).The remaining 20 healthy rats were divided into control and 4HR groups. We administered 4HR subcutaneously at a weekly dose of 10 mg/kg until the rats were euthanized. At 16 weeks of age, whole blood was collected, and microcomputed tomography of the skull and femur was performed. Results: All craniofacial linear measurements were smaller in the STZ group than in the control group. The mandibular molar width was significantly smaller in the 4HR group than in the control group (P = 0.031) but larger in the STZ/4HR group than in the STZ group (P = 0.011). Among the diabetic animals, the STZ/4HR group exhibited significantly greater cortical bone thickness, bone mineral density, and bone volume than the STZ group. Serum testosterone levels were also significantly higher in the STZ/4HR group than in the STZ group. @*Conclusions@#4HR administration may have divergent effects on mandibular growth and bone mass in healthy and diabetic rats. In the context of diabetes, 4HR appears to have beneficial effects, potentially through the modulation of mitochondrial respiration.

Efficacy and Cardiovascular Safety of Romosozumab: A Meta-analysis and Systematic Review

Background@#This systematic review and meta-analysis aimed to evaluate the efficacy and cardiovascular safety of romosozumab compared with placebo. @*Methods@#Randomized controlled trials (RCTs) were searched from Medline, EMBASE, Cochrane Central, and Web of Science until July 2022. Primary outcomes included the change in bone mineral density (BMD) from baseline at month 6. The secondary outcomes were the change of bone turnover markers (N-terminal propeptide of type 1 procollagen (P1NP); C-terminal telopeptide of type 1 collagen (CTX)) from baseline at month 3, and the incidence of cardiovascular adverse events for the total follow-up period. @*Results@#A total of 7 RCTs on 8,370patients were included. Romosozumab showed better effects in improving BMD in both lumbar spine and femoral neck at month 6 (standardized mean difference, SMD 2.20 [95% CI: 1.89-2.52], SMD 0.63 [95% CI: 0.41-0.86]). In contrast to placebo, romosozumab significantly increased PINP levels and reduced CTX levels at month 3 (SMD 0.93 [95% CI: 0.65-1.22], SMD −1.03 [95% CI: −1.23~ −0.82]. However, there was no significant difference in the composite incidence of cardiovascular adverse events and major adverse cardiovascular events (OR 1.16 [95% CI: 0.82-1.65], OR 1.08 [95% CI: 0.75-1.56]). @*Conclusion@#This analysis showed that romosozumab significantly improved BMD compared to placebo and was beneficial for change in bone turnover markers. There is no significant difference in the incidence of cardiovascular adverse events compared to placebo.

Characterization of a conjugated polysuccinimide-carboplatin compound

Carboplatin, an advanced anticancer drug with excellent efficacy against ovarian cancer, was developed to alleviate the side effects that often occur with cisplatin and other platinum-based compounds. Our study reports the in vitro characteristics, viability, and activity of cells expressing the inducible nitric oxide synthase (iNOS) gene after carboplatin was conjugated with polysuccinimide (PSI) and administered in combination with other widely used anticancer drugs. PSI, which has promising properties as a drug delivery material, could provide a platform for prolonging carboplatin release, regulating its dosage, and improving its side effects. The iNOS gene has been shown to play an important role in both cancer cell survival and inhibition. Herein, we synthesized a PSI-carboplatin conjugate to create a modified anticancer agent and confirmed its successful conjugation. To ensure its solubility in water, we further modified the structure of the PSI-carboplatin conjugate with 2-aminoethanol groups. To validate its biological characteristics, the ovarian cancer cell line SKOV-3 and normal ovarian Chinese hamster ovary cells were treated with the PSI-carboplatin conjugate alone and in combination with paclitaxel and topotecan, both of which are used in conventional chemotherapy. Notably, PSI-carboplatin conjugation can be used to predict changes in the genes involved in cancer growth and inhibition. In conclusion, combination treatment with the newly synthesized polymer-carboplatin conjugate and paclitaxel displayed anticancer activity against ovarian cancer cells but was not toxic to normal ovarian cancer cells, resulting in the development of an effective candidate anticancer drug without severe side effects.

Comparison of Outcomes of Multi-Level Anterior, Oblique, Transforaminal Lumbar Interbody Fusion Surgery : Impact on Global Sagittal Alignment

Objective@#: To compare the outcomes of anterior lumbar interbody fusion (ALIF), oblique lumbar interbody fusion (OLIF), and transforaminal lumbar interbody fusion (TLIF) in terms of global sagittal alignment. @*Methods@#: From January 2007 to December 2019, 141 adult patients who underwent multilevel interbody fusion for lumbar degenerative disorders were enrolled. Regarding the approach, patients were divided into the ALIF (n=23), OLIF (n=60), and TLIF (n=58) groups. Outcomes, including local radiographic parameters and global sagittal alignment, were then compared between the treatment groups. @*Results@#: Regarding local radiographic parameters, ALIF and OLIF were superior to TLIF in terms of the change in the anterior disc height (7.6±4.5 mm vs. 6.9±3.2 mm vs. 4.7±2.9 mm, p=0.000), disc angle (-10.0°±6.3° vs. -9.2°±5.2° vs. -5.1°±5.1°, p=0.000), and fused segment lordosis (-14.5°±11.3° vs. -13.8°±7.5° vs. -7.4°±9.1°, p=0.000). However, regarding global sagittal alignment, postoperative lumbar lordosis (-42.5°±9.6° vs. -44.4°±11.6° vs. -40.6°±12.3°, p=0.210), pelvic incidence-lumbar lordosis mismatch (7.9°±11.3° vs. 6.7°±11.6° vs. 11.5°±13.0°, p=0.089), and the sagittal vertical axis (24.3±28.5 mm vs. 24.5±34.0 mm vs. 25.2±36.6 mm, p=0.990) did not differ between the groups. @*Conclusion@#: Although the anterior approaches were superior in terms of local radiographic parameters, TLIF achieved adequate global sagittal alignment, comparable to the anterior approaches.

Rapid FEV 1 /FVC Decline Is Related With Incidence of Obstructive Lung Disease and Mortality in General Population

Background@#Forced expiratory volume in 1 second (FEV1 )/forced vital capacity (FVC) naturally decreases with age; however, an excessive decline may be related with increased morbidity and mortality. This study aimed to evaluate the FEV1 /FVC decline rate in the Korean general population and to identify whether rapid FEV1 /FVC decline is a risk factor for obstructive lung disease (OLD) and all-cause and respiratory mortality. @*Methods@#We evaluated individuals aged 40−69 years who underwent baseline and biannual follow-up spirometric assessments for up to 18 years, excluding those with airflow limitations at baseline. Based on the quartiles of the annual FEV1 /FVC decline rate, the most negative FEV1 /FVC change (1 st quartile of annual FEV1 /FVC decline rate) was classified as rapid FEV1 / FVC decline. We investigated the risk of progression to OLD and all-cause and respiratory mortality in individuals with rapid FEV1 /FVC decline. @*Results@#The annual FEV1 /FVC decline rate in the eligible 7,768 patients was 0.32 percentage point/year. The incidence rate of OLD was significantly higher in patients with rapid FEV1 / FVC decline than in those with non-rapid FEV1 /FVC decline (adjusted incidence rate, 2.119; 95% confidence interval [CI], 1.932–2.324). Rapid FEV1 /FVC decline was an independent risk factor for all-cause mortality (adjusted hazard [HR], 1.374; 95% CI, 1.105–1.709) and respiratory mortality (adjusted HR, 1.353; 95% CI, 1.089–1.680). @*Conclusion@#The annual FEV1 /FVC decline rate was 0.32%p in the general population in Korea. The incidence rate of OLD and the hazards of all-cause and respiratory mortality were increased in rapid FEV1 /FVC decliners.

Within-Host Evolution of SARS-CoV-2in a B-Cell Depleted Patient With Successful Treatment

Prolonged viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in an immunocompromised host is a challenge as the treatment and infection control for chronic coronavirus disease 2019 infection is not well established and there is a potential risk of new variants emerging. A 48-year-old woman who underwent chemotherapy, including rituximab and steroid, had reactivation of SARS-CoV-2 68 days after the virus was first detected. She successfully recovered after receiving convalescent plasma and intravenous immunoglobulin. Genomic analysis demonstrated that viruses collected from the nasopharyngeal specimens at day 0 and day 68 had 18 different nucleotide mutations, implying within-host evolution after in-depth epidemiologic investigation.

Functional Role of Phospholipase D in Bone Metabolism

Phospholipase D (PLD) proteins are major enzymes that regulate various cellular functions, such as cell growth, cell migration, membrane trafficking, and cytoskeletal dynamics. As they are responsible for such important biological functions, PLD proteins have been considered promising therapeutic targets for various diseases, including cancer and vascular and neurological diseases. Intriguingly, emerging evidence indicates that PLD1 and PLD2, 2 major mammalian PLD isoenzymes, are the key regulators of bone remodeling; this suggests that these isozymes could be used as potential therapeutic targets for bone diseases, such as osteoporosis and rheumatoid arthritis. PLD1 or PLD2 deficiency in mice can lead to decreased bone mass and dysregulated bone homeostasis. Although both mutant mice exhibit similar skeletal phenotypes, PLD1 and PLD2 play distinct and nonredundant roles in bone cell function. This review summarizes the physiological roles of PLD1 and PLD2 in bone metabolism, focusing on recent findings of the biological functions and action mechanisms of PLD1 and PLD2 in bone cells.

Anesthetic management of an elderly COVID-19 patient with pulmonary thromboembolism for hip surgery - A case report -

Background@#COVID-19 and delayed hip surgery are well-known risk factors for thromboembolism in elderly patients.Case: We report the case of an 88-year-old female patient with COVID-19 and pulmonary thromboembolism (PTE) who underwent delayed hip surgery 21 days after the injury. Heparinization and inferior vena cava filters were used to treat and prevent PTE. Transesophageal echocardiography and extracorporeal membrane oxygenation (ECMO) sheaths were inserted as a precaution in case of emergencies during surgery; the procedure was performed without any specific event. @*Conclusions@#COVID-19-infected patients suffering from a hip fracture have a high risk of thromboembolism, and therefore, require utmost attention for appropriate evaluation and prevention.

Lactobacillus reuteri ATG-F4 Alleviates Chronic Stress-induced Anhedonia by Modulating the Prefrontal Serotonergic System

Mental health is influenced by the gut-brain axis; for example, gut dysbiosis has been observed in patients with major depressive disorder (MDD).Gut microbial changes by fecal microbiota transplantation or probiotics treatment reportedly modulates depressive symptoms. However, it remains unclear how gut dysbiosis contributes to mental dysfunction, and how correction of the gut microbiota alleviates neuropsychiatric disorders. Our previous study showed that chronic consumption of Lactobacillus reuteri ATG-F4 (F4) induced neurometabolic alterations in healthy mice. Here, we investigated whether F4 exerted therapeutic effects on depressive-like behavior by influencing the central nervous system. Using chronic unpredictable stress (CUS) to induce anhedonia, a key symptom of MDD, we found that chronic F4 consumption alleviated CUS-induced anhedonic behaviors, accompanied by biochemical changes in the gut, serum, and brain. Serum and brain metabolite concentrations involved in tryptophan metabolism were regulated by CUS and F4. F4 consumption reduced the elevated levels of serotonin (5-HT) in the brain observed in the CUS group. Additionally, the increased expression of Htr1a, a subtype of the 5-HT receptor, in the medial prefrontal cortex (mPFC) of stressed mice was restored to levels observed in stress-naïve mice following F4 supplementation. We further demonstrated the role of Htr1a using AAV-shRNA to downregulate Htr1a in the mPFC of CUS mice, effectively reversing CUS-induced anhedonic behavior. Together, our findings suggest F4 as a potential therapeutic approach for relieving some depressive symptoms and highlight the involvement of the tryptophan metabolism in mitigating CUS-induced depressive-like behaviors through the action of this bacterium.

Immunogenicity and Safety of Vaccines against Coronavirus Disease in Actively Treated Patients with Solid Tumors: A Prospective Cohort Study / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#We aimed to assess the humoral response to and reactogenicity of coronavirus disease 2019 (COVID-19) vaccination according to the vaccine type and to analyze factors associated with immunogenicity in actively treated solid cancer patients (CPs). @*Materials and Methods@#Prospective cohorts of CPs, undergoing anticancer treatment, and healthcare workers (HCWs) were established. The participants had no history of previous COVID-19 and received either mRNA-based or adenovirus vector–based (AdV) vaccines as the primary series. Blood samples were collected before the first vaccination and after 2 weeks for each dose vaccination. Spike-specific binding antibodies (bAbs) in all participants and neutralizing antibodies (nAbs) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) wild-type, Delta, and Omicron variants in CPs were analyzed and presented as the geometric mean titer. @*Results@#Age-matched 20 HCWs and 118 CPs were included in the analysis. The bAb seroconversion rate and antibody concentrations after the first vaccination were significantly lower in CPs than in HCWs. After the third vaccination, antibody levels in CPs with a primary series of AdV were comparable to those in HCWs, but nAb titers against the Omicron variant did not quantitatively increase in CPs with AdV vaccine as the primary series. The incidence and severity of adverse reactions post-vaccination were similar between CPs and HCWs. @*Conclusion@#CPs displayed delayed humoral immune response after SARS-CoV-2 vaccination. The booster dose elicited comparable bAb concentrations between CPs and HCWs, regardless of the primary vaccine type. Neutralization against the Omicron variant was not robustly elicited following the booster dose in some CPs, implying the need for additional interventions to protect them from COVID-19.

Partial Pedicle Subtraction Osteotomy for Patients with Thoracolumbar Fractures : Comparative Study between Burst Fracture and Posttraumatic Kyphosis

Objective@#: To evaluate the surgical outcomes of partial pedicle subtraction osteotomy (PPSO) in patients with thoracolumbar fractures and compare the outcomes of PPSO for burst fractures with those for posttraumatic kyphosis (PTK). @*Methods@#: From June 2013 to May 2019, 20 consecutive adult patients underwent PPSO for thoracolumbar fractures at the levels of T10 to L2. Of these patients, 10 underwent surgery for acute fractures (burst fractures), and 10 for sequelae of thoracolumbar fractures (PTK). Outcomes of PPSO were evaluated and compared between the groups. @*Results@#: Twenty patients (each 10 patients of burst fractures and PTK) with a mean age of 64.7±11.1 years were included. The mean follow-up period was 21.8±11.0 months. The mean correction of the thoracolumbar angle was -34.9°±18.1° (from 37.8°±20.5°preoperatively to 2.8°±15.2° postoperatively). The mean angular correction at the PPSO site was -38.4°±13.6° (from 35.5°±13.6° preoperatively to -2.9°±14.1° postoperatively). The mean preoperative sagittal vertical axis was 93.5±6.7 cm, which was improved to 37.6±35.0 cm postoperatively. The mean preoperative kyphotic angle at the PPSO site was significant greater in patients with PTK (44.8°±7.2°) than in patients with burst fractures (26.2°±12.2°, p=0.00). However, the mean postoperative PPSO angle did not differ between the two groups (-5.9°±15.7° in patients with burst fractures and 0.2°±12.4° in those with PTK, p=0.28). The mean angular correction at the PPSO site was significantly greater in patients with PTK (-44.6°±10.7°) than in those with burst fractures (-32.1°±13.7°, p=0.04). The mean operation time was 188.1±37.6 minutes, and the mean amount of surgical bleeding was 1030.0±533.2 mL. There were seven cases of perioperative complications occurred in five patients (25%), including one case (5%) of neurological deficit. The operation time, surgical bleeding, and complication rates did not differ between groups. @*Conclusion@#: In cases of burst fracture, PPSO provided enough spinal cord decompression without corpectomy and produced sagittal correction superior to that achieved with corpectomy. In case of PTK, PPSO achieved satisfactory curve correction comparable to that achieved with conventional PSO, with less surgical time, less blood loss, and lower complication rates. PPSO could be a viable surgical option for both burst fractures and PTK.

Treatment of Human Immunodeficiency Virus-Associated Facial Lipoatrophy With Hyaluronic Acid Filler Mixed With Micronized Cross-Linked Acellular Dermal Matrix

Background@#Human immunodeficiency virus (HIV)-associated facial lipoatrophy (FLA) is a stigmatizing side effect associated with the use of highly active antiretroviral therapy. We sought to evaluate the safety and efficacy of the hyaluronic acid filler mixed with micronized cross-linked acellular dermal matrix (HA/MADM) in HIV-associated FLA. @*Methods@#We conducted an open-label safety and efficacy study in patients with HIVassociated FLA. Fourteen patients received single injection of the HA/MADM, and 13 patients completed the 24-week follow-up evaluation. Treatment efficacy, safety, and patient and physician satisfaction were evaluated. Repeated measure analysis of variance with post-hoc analysis with the Wilcoxon signed rank test was performed to compare and incorporate parameters at each time point. @*Results@#All 13 patients maintained a significant improvement of the Carruthers Lipoatrophy Severity Scale grade throughout the study period, along with improvement of the depressed volume due to lipoatrophy measured using a three-dimensional camera system. More than 80% of patients and physicians were satisfied with the treatment, and no treatment-related adverse events were reported, except for one case of transient subcutaneous nodule formation. @*Conclusion@#Our study findings suggest that injectable HA/MADM is a potentially effective and safe treatment option for treating HIV-positive patients with FLA.

Risk Factors and Patterns of Locoregional Recurrence after Radical Nephrectomy for Locally Advanced Renal Cell Carcinoma / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#We aimed to investigate the risk factors and patterns of locoregional recurrence (LRR) after radical nephrectomy (RN) in patients with locally advanced renal cell carcinoma (RCC). @*Materials and Methods@#We retrospectively analyzed 245 patients who underwent RN for non-metastatic pT3-4 RCC from January 2006 to January 2016. We analyzed the risk factors associated with poor locoregional control using Cox regression. Anatomical mapping was performed on reference computed tomography scans showing intact kidneys. @*Results@#The median follow-up duration was 56 months (range, 1 to 128 months). Tumor extension to renal vessels or the inferior vena cava (IVC) and Fuhrman’s nuclear grade IV were identified as independent risk factors of LRR. The 5-year actuarial LRR rates in groups with no risk factor, one risk factor, and two risk factors were 2.3%, 19.8%, and 30.8%, respectively (p < 0.001). The locations of LRR were distributed as follows: aortocaval area (n=2), paraaortic area (n=4), retrocaval area (n=5), and tumor bed (n=11). No LRR was observed above the celiac axis (CA) or under the inferior mesenteric artery (IMA). @*Conclusion@#Tumor extension to renal vessels or the IVC and Fuhrman’s nuclear grade IV were the independent risk factors associated with LRR after RN for pT3-4 RCC. The locations of LRR after RN for RCC were distributed in the tumor bed and regional lymphatic area from the bifurcation of the CA to that of the IMA.

Surveillance of Close Contacts and Implications of Pediatric Patients with COVID-19–Experiences from a Single Residential Treatment Center

Residential treatment centers (RTCs) are successful in isolating and closely monitoring adults confirmed with coronavirus disease 2019 (COVID-19), but there are concerns for children who need care. This study was conducted as a retrospective analysis of the surveillance of guardians who entered an RTC with infected pediatric patients to identify the secondary attack rate of COVID-19 to close contacts in a single RTC and to provide directions for developing guidelines for caregivers who co-isolate with infected children. When caregivers were admitted to this RTC, aside from negative confirmation before discharge, tests were additionally performed one or two times. There were 57 index children and adolescent patients who entered the RTC with their parents as caregivers. The secondary attack rate by pediatric patients to close contacts outside their households was 25% (95% confidence interval, 10.0 to 40.0) (8 out of 32 contacts). The transmissibility of SARS-CoV-2 in children was close to zero at 6 days after the confirmation tests. It is reasonable to test the close contacts of pediatric patients after 7 days of isolation to identify infections among caregivers.

Introduction of Non-Native Ticks Collected from Fresh Migratory Bird Carcasses on a Stopover Island in the Republic of Korea

When free-ranging birds are accidentally killed or die, there may be greater potential for their associated ticks to detach, seek alternate hosts, and become established. We examined 711 carcasses of 95 avian species for ticks at a stopover island of migratory birds in the Republic of Korea where only Ixodes nipponensis and I. persulcatus were previously reported from local mammals and vegetation. A total of 16 ticks, I. turdus and Haemaphysalis flava, were collected from 8 fresh carcasses belonging to 5 avian species. Despite their known abundance on migratory birds and mainland Korea, these species had not colonized the isolated insular ecosystem possibly due to the low abundance and diversity of local hosts. The results imply that increasing human impact, such as the anthropogenic mortality of migratory birds and the introduction of non-native mammalian hosts, will increase the potential invasion and colonization risk of ticks. This finding also suggests that tick surveillance consisting of fresh carcasses of dead migratory birds may provide additional information, often ignored in surveillance of ticks on live birds, for the potential introduction of non-native ticks and associated pathogens affecting animal and human health.

A Single Baseline Amyloid Positron Emission Tomography Could Be Sufficient for Predicting Alzheimer’s Disease Conversion in Mild Cognitive Impairment

Objective@#Baseline amyloid burden in mild cognitive impairment (MCI) has been linked to conversion to Alzheimer’s disease (AD), but the comparison of baseline and longitudinal changes in amyloid burden for predicting AD remains unresolved. The objectives of this study aimed to compare the prognostic ability of baseline and longitudinal changes in amyloid burden in MCI patients. @*Methods@#Seventy-five individuals with MCI were recruited and examined annually by clinical interviews for a mean follow-up of 24 months (range, 11.6–42.0). [18F]Florbetaben positron emission tomography (PET) scans were performed. T1-weighted 3D volumes were acquired for co-registration, and to define regions of interest. We examined whether baseline and longitudinal amyloid burden changes can improve AD conversion by Cox proportional hazard model analysis and receiver operating characteristic (ROC) curve analysis. @*Results@#Cox proportional hazards model analysis showed that baseline amyloid burden was significantly associated with increased risk of conversion to AD (hazard ratio [HR]=10.0; 95% confidence interval [CI], 1.15–85.39; p=0.04), but longitudinal amyloid burden changes was not (HR=0.2; 95% CI, 0.02–1.18; p=0.07). When predicting AD, longitudinal amyloid burden changes had better ROC accuracy of 65.2% (95% CI, 48.4–82.0) than baseline amyloid burden of 59.6% (95% CI, 40.3–79.0), without statistical significance in pairwise comparison. @*Conclusion@#A single baseline amyloid PET could be sufficient in the prediction of AD conversion in MCI.

Differential Diagnosis of Inflammatory Arthropathy Accompanying Active Tuberculosis Infection

Objective@#The study aimed to ascertain the clinical manifestations of inflammatory arthritis accompanying tuberculosis (TB) for the differential diagnosis. @*Methods@#We retrospectively reviewed patients with active TB who presented with inflammatory arthropathy at Seoul Medical Center. Among 2,872 patients with active TB infection, 47 had inflammatory arthropathy: 14 had crystal-induced arthropathy; 12, TB arthritis; 12, Poncet’s disease (PD); 8, Rheumatoid arthritis (RA); and 1, septic arthritis. The clinical characteristics and laboratory and radiographic findings of each group were analyzed. @*Results@#In TB arthritis, weight-bearing joints were more commonly affected than the elbow and wrist joints. When compared to TB arthritis, PD demonstrated a significantly higher proportion of polyarthritis and involved both large and small-to-mediumsized joints. The duration of arthritis symptoms after anti-TB treatment was significantly shorter in patients with PD (56 days vs. 90 days, p=0.028). When compared to PD, RA flares during active TB infection involved only small-to-medium-sized joints rather than a mixed distribution (62.5% vs. 16.7%, p=0.035). Patients with PD more commonly had fever at onset and showed a good response to nonsteroidal anti-inflammatory drugs alone or were in remission within 3 months after anti-TB treatment. The presence of rheumatoid factor or anti-cyclic citrullinated peptide and radiographic progression after 12 months was frequently observed in patients with RA flares. @*Conclusion@#The differential diagnosis of inflammatory arthritis accompanying active tuberculosis infection is challenging. Comprehensive history taking and physical examination, synovial fluid analysis, and a high level of clinical suspicion are essential to avoid delayed diagnosis and to reduce the significant morbidity involved.

A Case of African Tick-Bite Fever in a Returning Traveler from Southern Africa / 감염과화학요법

African tick-bite fever (ATBF), caused by Rickettsia africae, is the second most frequent cause of fever after malaria in travelers returning from Southern Africa. As the Korean outbound travelers are increasing every year, tick-borne rickettsial diseases as a cause of febrile illness are likely to increase. We describe a febrile Korean returning traveler who showed two eschars after visiting the rural field in Manzini, Swaziland. We performed nested polymerase chain reaction using the eschar and diagnosed the patient with ATBF. He was treated with oral doxycycline for 7 days, and recovered without any complications. We believe that the present case is the first ATBF case diagnosed in a Korean traveler.

Evaluation of Intervention Policies for the COVID-19Epidemic in the Seoul/Gyeonggi Region through a Model Simulation

Purpose@#To evaluate the efficacy of intervention policies on coronavirus disease-19 (COVID-19) dissemination. @*Materials and Methods@#An age-structured compartmental model for the COVID-19 outbreak was proposed to predict the impact of control measures in the Seoul/Gyeonggi region. The model was calibrated based on actual data and realistic situations, including daily vaccine doses, proportion of delta variant cases, and confirmed cases by age. We simulated different scenarios for non-pharmaceutical interventions by varying social distancing and school attendance strategies. @*Results@#Two-step mitigation of social distancing without in-person classes would result in a rapid increase in confirmed cases up to 10000 but would keep severe cases within the manageable range of the health care system. The overall impact of taking down the distancing level by one step with twice the increase in contacts at school was comparable to the above scenario. Implementation of two-step mitigation of social distancing along with a two-fold increase in contacts among the school-age group would dramatically increase confirmed and severe cases by over 80000 and 100, respectively, as early as the beginning of December. This policy would cause the situation to spiral out of control, considering the scale of the response and time to prepare. On the other hand, the burden on the current healthcare system caused by two-step mitigation of social distancing and 40% increased contacts in the school-age group was manageable if prepared. @*Conclusion@#A compromise between social distancing and school attendance policy and timely preparations for the spread of COVID-19 are required.