Time-variant reproductive number of COVID-19 in Seoul, Korea / 한국역학회지

OBJECTIVES@#To estimate time-variant reproductive number (Rt) of coronavirus disease 19 based on either number of daily confirmed cases or their onset date to monitor effectiveness of quarantine policies. @*METHODS@#Using number of daily confirmed cases from January 23, 2020 to March 22, 2020 and their symptom onset date from the official website of the Seoul Metropolitan Government and the district office, we calculated Rt using program R’s package “EpiEstim”. For asymptomatic cases, their symptom onset date was considered as -2, -1, 0, +1, and +2 days of confirmed date. @*RESULTS@#Based on the information of 313 confirmed cases, the epidemic curve was shaped like ‘propagated epidemic curve’. The daily Rt based on Rt_c peaked to 2.6 on February 20, 2020, then showed decreased trend and became <1.0 from March 3, 2020. Comparing both Rt from Rt_c and from the number of daily onset cases, we found that the pattern of changes was similar, although the variation of Rt was greater when using Rt_c. When we changed assumed onset date for asymptotic cases (-2 days to +2 days of the confirmed date), the results were comparable. @*CONCLUSIONS@#Rt can be estimated based on Rt_c which is available from daily report of the Korea Centers for Disease Control and Prevention. Estimation of Rt would be useful to continuously monitor the effectiveness of the quarantine policy at the city and province levels.

Time-variant reproductive number of COVID-19 in Seoul, Korea / 한국역학회지

OBJECTIVES@#To estimate time-variant reproductive number (Rt) of coronavirus disease 19 based on either number of daily confirmed cases or their onset date to monitor effectiveness of quarantine policies. @*METHODS@#Using number of daily confirmed cases from January 23, 2020 to March 22, 2020 and their symptom onset date from the official website of the Seoul Metropolitan Government and the district office, we calculated Rt using program R’s package “EpiEstim”. For asymptomatic cases, their symptom onset date was considered as -2, -1, 0, +1, and +2 days of confirmed date. @*RESULTS@#Based on the information of 313 confirmed cases, the epidemic curve was shaped like ‘propagated epidemic curve’. The daily Rt based on Rt_c peaked to 2.6 on February 20, 2020, then showed decreased trend and became <1.0 from March 3, 2020. Comparing both Rt from Rt_c and from the number of daily onset cases, we found that the pattern of changes was similar, although the variation of Rt was greater when using Rt_c. When we changed assumed onset date for asymptotic cases (-2 days to +2 days of the confirmed date), the results were comparable. @*CONCLUSIONS@#Rt can be estimated based on Rt_c which is available from daily report of the Korea Centers for Disease Control and Prevention. Estimation of Rt would be useful to continuously monitor the effectiveness of the quarantine policy at the city and province levels.

Acute UV Irradiation Increases Heparan Sulfate Proteoglycan Levels in Human Skin

Glycosaminoglycans are important structural components in the skin and exist as various proteoglycan forms, except hyaluronic acid. Heparan sulfate (HS), one of the glycosaminoglycans, is composed of repeated disaccharide units, which are glucuronic acids linked to an N-acetyl-glucosamine or its sulfated forms. To investigate acute ultraviolet (UV)-induced changes of HS and HS proteoglycans (HSPGs), changes in levels of HS and several HSPGs in male human buttock skin were examined by immunohistochemistry and real-time quantitative polymerase chain reaction (qPCR) after 2 minimal erythema doses (MED) of UV irradiation (each n = 4-7). HS staining revealed that 2 MED of UV irradiation increased its expression, and staining for perlecan, syndecan-1, syndecan-4, CD44v3, and CD44 showed that UV irradiation increased their protein levels. However, analysis by real-time qPCR showed that UV irradiation did not change mRNA levels of CD44 and agrin, and decreased perlecan and syndecan-4 mRNA levels, while increased syndecan-1 mRNA level. As HS-synthesizing or -degrading enzymes, exostosin-1 and heparanase mRNA levels were increased, but exostosin-2 was decreased by UV irradiation. UV-induced matrix metalloproteinase-1 expression was confirmed for proper experimental conditions. Acute UV irradiation increases HS and HSPG levels in human skin, but their increase may not be mediated through their transcriptional regulation.

A Fifteen-year Epidemiological Study of Ventriculoperitoneal Shunt Infections in Pediatric Patients: A Single Center Experience / 소아감염

PURPOSE: Ventriculoperitoneal (VP) shunt insertion is an important treatment modality in children with hydrocephalus. VP shunt infection is a major complication and an important factor that determines the surgery outcome. This 15-year study was performed to evaluate the epidemiology of VP shunt infections in pediatric patients treated at our center. METHODS: A retrospective review of medical records was performed in patients 18 years old or younger who underwent VP shunt insertion surgery from April 1995 to June 2010. RESULTS: Three hundred twenty-seven VP shunt surgeries were performed in a total of 190 pediatric patients (83 females, 107 males). The median age of the patients was 2.4 years (range, 0.02-17.9 years). Having a malignant brain tumor was the most frequent cause for VP shunt insertion. The shunt infection rate was 6.7% (22/327) per 100 operations and 9.5% (18/190) per 100 patients, and the incidence rate was 0.45 infection cases per 100 shunt operations-year. The most common pathogen was coagulase-negative staphylococcus (n=7) followed by methicillin resistant Staphylococcus aureus (n=1). Ten cases were treated with vancomycin and beta-lactam antibiotic (cephalosporin or carbapenem) combination therapy and 7 cases were treated with vancomycin monotherapy. The median duration of antibiotic treatment was 26 days (range, 7 to 58 days). Surgical intervention was performed in 18 cases (18/22, 81.8%). CONCLUSION: Epidemiologic information regarding VP shunt infections in pediatric patients is valuable that will help guide proper antibiotic management. Additional studies on the risk factors for developing VP shunt infections are also warranted.

Transcriptional Regulation of Proteoglycans and Glycosaminoglycan Chain-synthesizing Glycosyltransferases by UV Irradiation in Cultured Human Dermal Fibroblasts

Various kinds of glycosaminoglycans (GAGs) and proteoglycans (PGs) have been known to be involved in structural and space-filling functions, as well as many physiological regulations in skin. To investigate ultraviolet (UV) radiation-mediated regulation of GAGs and PGs in cultured human dermal fibroblasts, transcriptional changes of many types of PGs and GAG chain-synthesizing enzymes at 18 hr after 75 mJ/cm2 of UV irradiation were examined using quantitative real-time polymerase chain reaction methods. Hyaluronic acid synthase (HAS)-1, -2, and -3 and hyaluronidase-2 mRNA expressions were significantly increased by UV irradiation. Expressions of lumican, fibromodulin, osteoglycin, syndecan-2, perlecan, agrin, versican, decorin, and biglycan were significantly decreased by UV irradiation, while syndecan-1 was increased. Expressions of GAG chain-synthesizing glycosyltransferases, xylosyltransferase-1, beta1,3-glucuronyltransferase-1, beta1,4-galactosyltransferase-2, -4, exostosin-1, chondroitin polymerizing factor, and chondroitin sulfate synthase-3 were significantly reduced, whereas those of beta1,3-galactosyltransferase-6, beta1,4-galactosyltransferase-3, -7, beta-1,3-N-acetylglucosaminyltran sferase-2, and -7 were increased by UV irradiation. Heparanase-1 mRNA expression was increased, but that of heparanase-2 was reduced by UV irradiation. Time-course investigation of representative genes showed consistent results. In conclusion, UV irradiation may increase hyaluronic acid production through HAS induction, and decrease other GAG productions through downregulation of PG core proteins and GAG chain-synthesizing glycosyltransferases in cultured human dermal fibroblasts.

Prevention of UV-Induced Skin Damages by 11,14,17-Eicosatrienoic Acid in Hairless Mice In Vivo

Polyunsaturated fatty acids (PUFAs) are known to play important roles in various physiological and pathological processes. Recent studies have shown that some omega-3 (omega-3) PUFAs, such as eicosapentaenoic acid (EPA) and dodecahexaenoic acid (DHA), have protective effects on acute and chronic UV-induced changes. However, the effects of other omega-3 PUFAs including 11,14,17-eicosatrienoic acid (20:3) (ETA) on UV-induced skin damages are poorly understood. In this study, we investigated the cutaneous photoprotective effects of ETA in hairless mice in vivo. Female HR-1 hairless mice were topically treated with vehicle (ethanol:polyethylene glycol=30:70) only, 0.1% ETA, or 1% ETA once a day for 3 successive days after one time UV irradiation (200 mJ/cm2) on dorsal skins. Skin biopsy was carried out on the fourth day (72 hr after UV irradiation). We found that topical treatment with ETA attenuated UV-induced epidermal and dermal thickness and infiltration of inflammatory cells, and impairment of skin barrier function. In addition, ETA suppressed the expression of IL-1beta, COX-2, and MMP-13 induced by UV irradiation. Our results show that the topical application of ETA protects against UV-induced skin damage in hairless mice and suggest that ETA can be a potential agent for preventing and/or treating UV-induced inflammation and photoaging.

The peroxisome proliferator-activated receptor-gamma agonist, Rosiglitazone, improves aortic wall stiffness in type 2 diabetic patients / 대한내과학회지

BACKGROUND: Diabetes is a major risk factor for the development of coronary artery disease. Atherosclerosis is thought to arise as a result of a chronic inflammatory process within the arterial wall. Insulin resistance is central to the pathogenesis of type 2 diabetes and may contribute to atherosclerosis, either directly or through associated risk factors. Rosiglitazone, a peroxisome proliferator-activated receptor gamma agonist, is used in the treatment of type 2 diabetes mellitus, and previous findings suggest that it may have anti-inflammatory effects on atherosclerosis. This study was performed to evaluate whether rosiglitazone can improve arterial stiffness in type 2 diabetic patients. METHODS: This study consisted of 40 patients with type 2 diabetes. These subjects were classified into two groups either medicated with glimepiride (GLIME group, 61.5+/-8.2 years, M:F = 9:11) or with glimepiride and rosiglitazone (ROSI group, 65.6+/-9.5 years, M:F = 4:16). For each group, plasma a hsCRP, lipid profile, HOMAIR and HbA1c were measured before and after 12 months of medical treatment. At the same time, pulse wave velocity (PWV) using an automatic device (PP 1000, Hanbyul, Jeonju, Korea) was measured. RESULTS: The plasma hsCRP level was significantly decreased in the ROSI group as compared with the GLIME group (4.22+/-4.65 vs. 1.07+/-0.80 mg/L, p=0.025). The carotid-femoral PWV of the ROSI group improved significantly as compared with the GLIME group (8.29+/-1.25 vs. 7.26+/-1.49 m/sec, p=0.024). The changes of PWV were correlated with the changes of hsCRP (r=0.412, p=0.033). CONCLUSIONS: These findings suggest that rosiglitazone can improve the arterial stiffness in type 2 diabetic patients.

Squamous cell carcinoma of the finger and toe / 대한피부과학회지

BACKGROUND: Squamous cell carcinoma of the finger and toe is a relatively rare disorder which has often been misdiagnosed for years before definite diagnosis. Squamous cell carcinoma of the finger has usually been found to be associated with type 16 human papillomavirus (HPV). OBJECTIVES: To describe the clinical and histological features of 12 squamous cell carcinomas of the finger and toe, and to evaluate these lesions for the presence of HPV. METHOD: The clinical and histological features were reviewed. Immunohistochemical staining and PCR were performed in paraffin embedded tissue sections for detection of the presence of HPV infection. RESULTS: Patients presented with an erosive or a verrucous papule. Histologically, 2 lesions demonstrated bowenoid features, 9 lesions demonstrated well differentiated squamous cell carcinoma, and 1 lesion demonstrated verrucous carciroma-like features. By immunohistochenical staining and PCR, we could not demonstrate any evidence of HPV infection in any of the cases. The affected digit was amputated in 10 cases, and complete excision of the skin lesion was done in 2 cases. CONCLUSION: Squamous cell carcinoma of the finger and toe is not as rare as has been implied by early literature. It is important to carry out the skin biopsy from all recalcitrant lesions of the finger and toe.

An electromyographic investigation of masticatory muscles in normal occlusion and Class II malocclusion / 대한치과교정학회지

Along with form and function relationship of craniofacial growth comes a concern for the masticatory muscles with postnormal occlusion. It is the aim of this study to grope the certain differences upon the electromyographic activities of the masticatory muscles between normal occlusion and class II malocclusion during the varieties of oral functions. 26 persons of normal occlusion whose mean age were 18.9-25.6 years and another 26 persons of class II malocclusion whose mean age were 19.0-28.9 years served for this study. The electromyographic recordings processed by Medelec(R) MS 25 EMG apparatus were taken from the anterior and posterior temporal, and anterior and posterior masseter muscles of both sides, and suprahyoid muscles as well. Analyses of the data toward such specific activities as mandibular rest, maximal biting, chewing gums and swallowing peanuts turned out the following summary and conclusions. 1. The maximal mean amplitude of the posterior temporalis showed significant augmentation in class II malocclusion, however the anterior temporalis, posterior masseter, and suprahyoid muscles manifested meaningful diminutions. 2. Stronger posterior temporalis and weaker anterior masseter and suprahyoid muscles were arranged in maximal biting with parameters of maximal mean amplitude. 3. The anterior temporalis of working side expressed smaller maximal mean amplitude in class II malocclusion. Significant swelling in duration were shown at anterior and posterior temporalis of working side, and posterior temporalis of balancing side in class II malocclusion, and marked reduction at anterior masseter of balancing side and posterior masseter of working side as well. The lessened latency were expressed at anterior masseter of working side, and anterior and posterior masseter of balancing side. Class II malocclusion group had significant prolongation of silent period duration. Mean silent period duration of 10.75 msec in normal occlusion and 24.37 msec in class II malocclusion were calculated. 4. Significant augmentations of maximal mean amplitude while swallowing peanuts were yielded at right anterior temporalis and posterior temporalis of both sides, however left anterior masseter and right posterior masseter showed diminution. No significant differences in duration showed at every muscle examined in class II malocclusion group. 5. Weaker masseter and stronger temporalis were suggested as characteristics of class II malocclusion.