PURPOSE: Oak is the dominant tree species in Korea. Oak pollen has the highest sensitivity rate among all allergenic tree species in Korea. A deep neural network (DNN)-based estimation model was developed to determine the concentration of oak pollen and overcome the shortcomings of conventional regression models. METHODS: The DNN model proposed in this study utilized weather factors as the input and provided pollen concentrations as the output. Weather and pollen concentration data were used from 2007 to 2016 obtained from the Korea Meteorological Administration pollen observation network. Because it is difficult to prevent over-fitting and underestimation by using a DNN model alone, we developed a bootstrap aggregating-type ensemble model. Each of the 30 ensemble members was trained with random sampling at a fixed rate according to the pollen risk grade. To verify the effectiveness of the proposed model, we compared its performance with those of models of regression and support vector regression (SVR) under the same conditions, with respect to the prediction of pollen concentrations, risk levels, and season length. RESULTS: The mean absolute percentage error in the estimated pollen concentrations was 11.18%, 10.37%, and 5.04% for the regression, SVR and DNN models, respectively. The start of the pollen season was estimated to be 20, 22, and 6 days earlier than that predicted by the regression, SVR and DNN models, respectively. Similarly, the end of the pollen season was estimated to be 33, 20, and 9 days later that predicted by the regression, SVR and DNN models, respectively. CONCLUSIONS: Overall, the DNN model performed better than the other models. However, the prediction of peak pollen concentrations needs improvement. Improved observation quality with optimization of the DNN model will resolve this issue.
Korea ; Pollen ; Quercus ; Rhinitis, Allergic ; Rhinitis, Allergic, Seasonal ; Seasons ; Trees ; Weather

BACKGROUND AND PURPOSE: Few studies have investigated the relationship between the specific functional factors potentially associated with functional level and stroke recurrence. We conducted a study of patients with noncardioembolic ischemic stroke (NCIS) to determine the functional factors affecting recurrence within the first year. METHODS: In total, 568 first-ever NCIS patients (age=65.1±17.4 years, mean±SD) were analyzed in a multicenter, prospective cohort study registered from August 2012. Demographic characteristics, past medical history, comorbidities, laboratory data, stroke features in neuroimaging, acute treatments, and medications at discharge were assessed. Functional factors reflecting gross functional impairment, ambulatory function, motor function, activities of daily living, cognition, language ability, swallowing function, mood, and quality of life were comprehensively evaluated in face-to-face assessments using standardized tools at the time of discharge. RESULTS: The cumulative incidence of stroke recurrence in NCIS was 6.0% (n=34) at 1 year. The period from admission to discharge was 34.4±7.0 days. The independent predictors of stroke recurrence within 1 year in multivariate Cox proportional-hazards regression analyses were 1) age [per-year hazard ratio (HR)=1.04, 95% confidence interval (CI)=0.97–1.06, p=0.048], 2) Charlson Comorbidity Index higher than 2 (HR=1.72, 95% CI=1.26–2.22, p=0.016), 3) modified Rankin Scale score of 3 or more at discharge (HR=1.56, 95% CI=1.22–1.94, p=0.032), and 4) Functional Ambulation Category of 3 or less at discharge (HR=2.56, 95% CI=1.84–3.31, p=0.008). CONCLUSIONS: In addition to patient age, moderate-to-severe functional impairment requiring the help of others (especially for ambulation) at the time of discharge and the severity of comorbidity were independent predictors of stroke recurrence within 1 year of the first NCIS.
Activities of Daily Living ; Cognition ; Cohort Studies* ; Comorbidity ; Deglutition ; Disability Evaluation ; Humans ; Incidence ; Language ; Neuroimaging ; Prospective Studies ; Quality of Life ; Recurrence* ; Rehabilitation* ; Stroke* ; Walking

BACKGROUND: Dexmedetomidine, an α2-adrenergic agonist, can be used for sedation and as an adjuvant to anesthetics. This study aimed to evaluate the effects of preanesthetic administration of dexmedetomidine on the propofol and remifentanil requirement during general anesthesia and postoperative pain in patients undergoing laparoscopic cholecystectomy. METHODS: Sixty patients were randomly assigned to group D or S (n = 30 each). Dexmedetomidine (0.5 µg/kg) and a comparable volume of saline were administered in groups D and S, respectively, over a 10 minutes period before induction. General anesthesia was induced and maintained with propofol and remifentanil; the bispectral index was maintained at 40–60. The intraoperative remifentanil and propofol dosages were recorded, and postoperative pain was assessed using a visual analog scale (VAS). RESULTS: In groups S and D, propofol dosage was 8.52 ± 1.64 and 6.83 ± 1.55 mg/kg/h, respectively (P < 0.001), while remifentanil dosage was 7.18 ± 2.42 and 4.84 ± 1.44 µg/ kg/h, respectively (P < 0.001). VAS scores for postoperative pain were 6.50 (6–7) and 6.0 (6–7), respectively, at 30 minutes (P = 0.569), 5 (4–5) and 4 (3–5), respectively, at 12 hours (P = 0.039), and 2 (2–3) and 2 (1.25–2), respectively, at 24 hours (P = 0.044). The Friedman test revealed that VAS scores changed over time in both groups (P < 0.001). CONCLUSIONS: Preanesthetic single administration of a low dose of dexmedetomidine (0.5 µg/kg) can significantly decrease the remifentanil and propofol requirement during short surgeries and alleviate postoperative pain.
Anesthesia, General ; Anesthetics ; Cholecystectomy, Laparoscopic* ; Dexmedetomidine* ; Humans ; Pain, Postoperative ; Propofol* ; Visual Analog Scale

PURPOSE: Dexrazoxane has been used as an effective cardioprotector against anthracycline cardiotoxicity. This study intended to analyze cardioprotective efficacy and secondary malignancy development, and elucidate risk factors for secondary malignancies in dexrazoxane-treated pediatric patients. MATERIALS AND METHODS: Data was collected from 15 hospitals in Korea. Patients who received any anthracyclines, and completed treatment without stem cell transplantation were included. For efficacy evaluation, the incidence of cardiac events and cardiac event-free survival rates were compared. Data about risk factors of secondary malignancies were collected. RESULTS: Data of total 1,453 cases were analyzed; dexrazoxane with every anthracyclines group (D group, 1,035 patients) and no dexrazoxane group (non-D group, 418 patients). Incidence of the reported cardiac events was not statistically different between two groups; however, the cardiac event-free survival rate of patients with more than 400 mg/m2 of anthracyclines was significantly higher in D group (91.2% vs. 80.1%, p=0.04). The 6-year cumulative incidence of secondary malignancy was not different between both groups after considering follow-up duration difference (non-D, 0.52%±0.37%; D, 0.60%±0.28%; p=0.55). The most influential risk factor for secondary malignancy was the duration of anthracycline administration according to multivariate analysis. CONCLUSION: Dexrazoxane had an efficacy in lowering cardiac event-free survival rates in patients with higher cumulative anthracyclines. As a result of multivariate analysis for assessing risk factors of secondary malignancy, the occurrence of secondary malignancy was not related to dexrazoxane administration.
Anthracyclines ; Cardiotoxicity ; Dexrazoxane ; Disease-Free Survival ; Follow-Up Studies ; Humans ; Incidence ; Korea ; Multivariate Analysis ; Neoplasms, Second Primary ; Risk Factors* ; Stem Cell Transplantation

PURPOSE: Head and neck squamous cell carcinoma (HNSCC) is a deadly disease in which precision medicine needs to be incorporated. We aimed to implement next-generation sequencing (NGS) in determining actionable targets to guide appropriate molecular targeted therapy in HNSCC patients. MATERIALS AND METHODS: Ninety-three tumors and matched blood samples underwent targeted sequencing of 244 genes using the Illumina HiSeq 2500 platform with an average depth of coverage of greater than 1,000×. Clinicopathological data from patients were obtained from 17 centers in Korea, and were analyzed in correlation with NGS data. RESULTS: Ninety-two of the 93 tumors were amenable to data analysis. TP53 was the most common mutation, occurring in 47 (51%) patients, followed by CDKN2A (n=23, 25%), CCND1 (n=22, 24%), and PIK3CA (n=19, 21%). The total mutational burden was similar between human papillomavirus (HPV)–negative vs. positive tumors, although TP53, CDKN2A and CCND1 gene alterations occurred more frequently in HPV-negative tumors. HPV-positive tumors were significantly associated with immune signature-related genes compared to HPV-negative tumors. Mutations of NOTCH1 (p=0.027), CDKN2A (p < 0.001), and TP53 (p=0.038) were significantly associated with poorer overall survival. FAT1 mutations were highly enriched in cisplatin responders, and potentially targetable alterations such as PIK3CA E545K and CDKN2A R58X were noted in 14 patients (15%). CONCLUSION: We found several targetable genetic alterations, and our findings suggest that implementation of precision medicine in HNSCC is feasible. The predictive value of each targetable alteration should be assessed in a future umbrella trial using matched molecular targeted agents.
Biomarkers ; Carcinoma, Squamous Cell* ; Cisplatin ; Epithelial Cells* ; Head* ; Humans ; Korea ; Molecular Targeted Therapy ; Neck* ; Precision Medicine ; Statistics as Topic

BACKGROUND: The standard morphological evaluation has been widely used for embryo selection, but it has limitations. This study aimed to investigate the correlation between morphologic grading and euploidy rate of in vitro fertilization (IVF) preimplantation genetic screening (PGS) and compare the pregnancy rates in young and old ages. METHODS: This is a retrospective study using the medical records of patients who underwent IVF procedures with PGS between January 2016 and February 2017 in a single center. The embryo grades were categorized into 4 groups: excellent, good, fair, and poor. Basic characteristics, euploidy rates, clinical pregnancy (CP) rates and ongoing pregnancy rates were analyzed. RESULTS: The excellent group had significantly higher rate of euploid embryos than fair group (47.82% vs. 29.33%; P = 0.023) and poor group (47.82% vs. 29.60%; P = 0.005). When the four groups were recategorized into two groups (excellent and good vs. fair and poor), they also showed significant difference in euploidy rates (44.52% vs. 29.53%; P = 0.002). When the patients were divided into two groups by age 35, the CP rates for those under and over 35 years old were 44.74% and 47.83%, respectively, which showed no significant difference. CONCLUSION: The significant differences among the euploidy rates of different morphologic embryo grades demonstrated the positive correlations between the morphologic grading of the embryo and the euploidy rate of PGS. Additionally, there was no significant difference between the younger and older patients' CP rates. These findings emphasize the fact that old age patients might benefit from PGS whatever the indication of PGS is.
Blastocyst* ; Embryonic Structures ; Fertilization in Vitro* ; Genetic Testing* ; Humans ; In Vitro Techniques* ; Medical Records ; Pregnancy ; Pregnancy Rate ; Retrospective Studies

The global obesity epidemic and associated metabolic diseases require alternative biological targets for new therapeutic strategies. In this study, we show that a phytochemical sulfuretin suppressed adipocyte differentiation of preadipocytes and administration of sulfuretin to high fat diet-fed obese mice prevented obesity and increased insulin sensitivity. These effects were associated with a suppressed expression of inflammatory markers, induced expression of adiponectin, and increased levels of phosphorylated ERK and AKT. To elucidate the molecular mechanism of sulfuretin in adipocytes, we performed microarray analysis and identified activating transcription factor 3 (Atf3) as a sulfuretin-responsive gene. Sulfuretin elevated Atf3 mRNA and protein levels in white adipose tissue and adipocytes. Consistently, deficiency of Atf3 promoted lipid accumulation and the expression of adipocyte markers. Sulfuretin’s but not resveratrol’s anti-adipogenic effects were diminished in Atf3 deficient cells, indicating that Atf3 is an essential factor in the effects of sulfuretin. These results highlight the usefulness of sulfuretin as a new anti-obesity intervention for the prevention of obesity and its associated metabolic diseases.
Activating Transcription Factor 3 ; Adipocytes ; Adiponectin ; Adipose Tissue, White ; Animals ; Diet* ; Insulin Resistance ; Metabolic Diseases* ; Mice ; Mice, Obese* ; Microarray Analysis ; Obesity* ; RNA, Messenger

Oxidative stress is considered a major contributor in the pathogenesis of diabetic neuropathy and in diabetes complications, such as nephropathy and cardiovascular diseases. Diabetic neuropathy, which is the most frequent complications of diabetes, affect sensory, motor, and autonomic nerves. This study aimed to investigate whether 7,8-dihydroxyflavone (7,8-DHF) protects SH-SY5Y neuronal cells against high glucose-induced toxicity. In the current study, we found that diabetic patients exhibited higher lipid peroxidation caused by oxidative stress than healthy subjects. 7,8-DHF exhibits superoxide anion and hydroxyl radical scavenging activities. High glucose-induced toxicity severely damaged SH-SY5Y neuronal cells, causing mitochondrial depolarization; however, 7,8-DHF recovered mitochondrial polarization. Furthermore, 7,8-DHF effectively modulated the expression of pro-apoptotic protein (Bax) and anti-apoptotic protein (Bcl-2) under high glucose, thus inhibiting the activation of caspase signaling pathways. These results indicate that 7,8-DHF has antioxidant effects and protects cells from apoptotic cell death induced by high glucose. Thus, 7,8-DHF may be developed into a promising candidate for the treatment of diabetic neuropathy.
Antioxidants ; Autonomic Pathways ; Cardiovascular Diseases ; Cell Death ; Diabetes Complications ; Diabetic Neuropathies ; Glucose ; Healthy Volunteers ; Humans ; Hydroxyl Radical ; Lipid Peroxidation ; Neurons* ; Oxidative Stress* ; Superoxides

PURPOSE: The purpose of this study was to investigate the effect of hospital case volume on clinical outcomes in patients with nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: Data on 1,073 patients with cT1-4N0-3M0 NPC were collected from a multi-institutional retrospective database (KROG 11-06). All patients received definitive radiotherapy (RT) either with three-dimensional-conformal RT (3D-CRT) (n=576) or intensity-modulated RT (IMRT) (n=497). The patients were divided into two groups treated at high volume institution (HVI) (n=750) and low volume institution (LVI) (n=323), defined as patient volume ≥ 10 (median, 13; range, 10 to 18) and < 10 patients per year (median, 3; range, 2 to 6), respectively. Endpoints were overall survival (OS) and loco-regional progression-free survival (LRPFS). RESULTS: At a median follow-up of 56.7 months, the outcomes were significantly better in those treated at HVI than at LVI. For the 614 patients of propensity score-matched cohort, 5-year OS and LRPFS were consistently higher in the HVI group than in the LVI group (OS: 78.4% vs. 62.7%, p < 0.001; LRPFS: 86.2% vs. 65.8%, p < 0.001, respectively). According to RT modality, significant difference in 5-year OS was observed in patients receiving 3D-CRT (78.7% for HVI vs. 58.9% for LVI, p < 0.001) and not in those receiving IMRT (77.3% for HVI vs. 75.5% for LVI, p=0.170). CONCLUSION: A significant relationship was observed between HVI and LVI for the clinical outcomes of patients with NPC. However, the difference in outcome becomes insignificant in the IMRT era, probably due to the standardization of practice by education.
Cohort Studies ; Disease-Free Survival ; Education ; Follow-Up Studies ; Humans ; Nasopharyngeal Neoplasms ; Radiotherapy ; Radiotherapy, Intensity-Modulated ; Retrospective Studies* ; Treatment Outcome

OBJECTIVES: Postoperative cheek cyst (POCC) is a late postoperative complication of radical maxillary sinus surgery including the Caldwell-Luc (C-L) operation. The present study aimed to evaluate the therapeutic outcomes of surgical treatment for POCC and to assess the clinical factors correlated to these outcomes. METHODS: This study included 57 patients (67 nostrils) diagnosed with POCC who underwent surgical drainage. The medical records of the patients were retrospectively reviewed for radiological findings, treatment modalities, residual symptoms, and recurrences. RESULTS: In total, 30 patients were male and 27 patients were female with a mean age of 55 years, and the patients were usually diagnosed with POCC 28.2 years after radical surgery. Endonasal endoscopic marsupialization was performed via inferior meatal antrostomy, and if possible, middle meatal antrostomy was performed at the same time. In patients with cysts that were difficult to reach using an endonasal endoscopic approach, additional open C-L approaches were performed. The median follow-up period was 19.4 months. Overall, adequate drainage and symptomatic relief were achieved in 91% (61/67) of the patients. The recurrence rate was significantly higher in patients who had anterolateral POCC. Failure to achieve symptomatic relief was correlated to a smaller cyst and the use of the open C-L approach for drainage. CONCLUSION: The location and size of the cyst as well as the use of the open surgical approach were important factors in predicting the therapeutic outcome of POCC. The time point of treatment and surgical approaches should be based on the above-mentioned findings.
Cheek ; Drainage ; Female ; Follow-Up Studies ; Humans ; Male ; Maxillary Sinus ; Medical Records ; Mucocele ; Postoperative Complications ; Recurrence ; Retrospective Studies ; Treatment Outcome