Korean fog probability retrieval using remote sensing combined with machine-learning

Fog is a phenomenon that occurs very close to the ground or sea level, and when detected by satellite, it is difficult to distinguish it from the low-level cloud. Logistic regression can help identify the false detection of the low-level cloud as fog and improve the accuracy of fog detection. In this study, a Korean fog detection algorithm was developed by using a machine learning-based logistic regression model (LRM) at three time points throughout the day (daytime, nighttime, and dawn/dusk) according to the solar zenith angle. The visible reflectance (Ref) and infrared brightness temperature (BT) of Himawari-8, solar zenith angle, land/sea mask, digital elevation angle, clear-sky Ref, and clear-sky BT excluding cloud pixels, from 2017 to 2018, were used as training data. The model was constructed by selecting variables with high correlation with the target data through a stepwise elimination method among input data having independent relationships between variables. Cross-validation using test data (20% of training data) contributed to the optimization of LRM. The fog detection performance of LRM confirmed by cross-validation has a stability of 83%–94% with high accuracy. For quantitative validation in 2019 using a 3 × 3-pixel validation method, the average probability of detection (POD) in the spring was 0.89–0.92, while the false alarm rate (FAR) was 0.39–0.41; in autumn, the POD was 0.9–0.97 and FAR was 0.29–0.4. The sophistication of the threshold between fog and non-fog can affect the performance improvement of the model. Further evaluation of the fog detection accuracy confirmed the reliability of the fog probability based on the stepwise probability. Satellite images enabled quantitative comparisons and validation of the proposed method; the results indicate that the approach is stable, reliable, and accurate. LRM fog detection will contribute to the Korean fog detection forecast with high performance, while the machine learning method used to build LRM can improve the performance of other meteorological forecast systems

Ipsilateral Recurrence of DCIS in Relation to Radiomics Features on Contrast Enhanced Breast MRI

The purpose of this retrospective study was to investigate the association between ipsilateral recurrence of ductal carcinoma in situ (DCIS) and radiomics features from DCIS and contralateral normal breast on contrast enhanced breast MR imaging. A total of 163 patients with DCIS who underwent preoperative MR imaging between January 2010 and December 2014 were included (training cohort; n = 117, validation cohort; n = 46). Radiomics features were extracted from whole tumor volume of DCIS on early dynamic T1-subtraction images and from the contralateral normal breast on precontrast T1 and early dynamic T1-subtraction images. After feature selection, a Rad-score was established by LASSO Cox regression model. Performance of Rad-score was evaluated by the receiver operating characteristic (ROC) curve and Kaplan Meier curve with log rank test. The Rad-score was significantly associated with ipsilateral recurrence free survival (RFS). The low-risk group with a low Rad-score showed higher ipsilateral RFS than the high-risk group with a high Rad-score in both training and validation cohorts (p < 0.01). The Rad-score based on radiomics features from DCIS and contralateral normal breast on breast MR imaging showed the potential for prediction of ipsilateral RFS of DCIS

Cytotoxic Compounds from Juglans sinensis Dode Display Anti-Proliferative Activity by Inducing Apoptosis in Human Cancer Cells

Phytochemical investigation of the bark of Juglans sinensis Dode (Juglandaceae) led to the isolation of two active compounds, 8-hydroxy-2-methoxy-1,4-naphthoquinone (1) and 5-hydroxy-2-methoxy-1,4-naphthoquinone (2), together with 15 known compounds 3–17. All compounds were isolated from this plant for the first time. The structures of 1 and 2 were elucidated by spectroscopic data analysis, including 1D and 2D NMR experiments. Compounds 1–17 were tested for their cytotoxicity against the A549 human lung cancer cell line; compounds 1 and 2 exhibited significant cytotoxicity and additionally had potent cytotoxicity against six human cancer cell lines, MCF7 (breast cancer), SNU423 (liver cancer), SH-SY5Y (neuroblastoma), HeLa (cervical cancer), HCT116 (colorectal cancer), and A549 (lung cancer). In particular, breast, colon, and lung cancer cells were more sensitive to the treatment using compound 1. In addition, compounds 1 and 2 showed strong cytotoxic activity towards human breast cancer cells MCF7, HS578T, and T47D, but not towards MCF10A normal-like breast cells. They also inhibited the colony formation of MCF7, A549, and HCT116 cells in a dose-dependent manner. Flow cytometry analysis revealed that the percentage of apoptotic cells significantly increased in MCF7 cells upon the treatment with compounds 1 and 2. The mechanism of cell death caused by compounds 1 and 2 may be attributed to the upregulation of Bax and downregulation of Bcl2. These findings suggest that compounds 1 and 2 may be regarded as potential therapeutic agents against cancer

The changes of subtypes in pediatric diabetes and their clinical and laboratory characteristics over the last 20 years

PurposeWe studied the changes in subtypes of diabetes mellitus (DM) in children and evaluated the characteristics of each group over the past 20 years. In addition, we also examined the correlation between the glycated hemoglobin (HbA1c) values at the time of diagnosis and lipid profiles.MethodsThe patients were divided into 2 groups: there were a total of 190 patients under 20 years of age firstly diagnosed with DM in Ajou University Hospital. The patients in groups I and II were diagnosed from September 1995 to December 2004 and from January 2005 to April 2014, respectively.ResultsThe characteristics were compared between the 2 groups of patients. The result showed an increase in percentage of type 2 diabetes and maturity onset diabetes of the young (MODY) patients between the 2 groups. HbA1c and total cholesterol level had statistical significances to explain increasing the low-density lipoprotein cholesterol level among age, HbA1c, total cholesterol level, and z-scores of weight and body mass index (BMI) in type 2 diabetes. R-square was 0.074. However, z-score of BMI and total cholesterol level, not HbA1c, had statistical significances in type 1 diabetic patients. R-square was 0.323.ConclusionThe increase in the proportions of both type 2 diabetes and MODY in the last 10 years needed to be reminded when diagnosing the subtypes of DM, and the dyslipidemia should be attended more as a common problem of pediatric diabetic patients

Development of 3D Cell Printed Patch-Type Stem Cell Therapy for Treatment of Liver Cirrhosis

Liver cirrhosis is an irreversible end-stage liver disease which has no effective therapy except for liver transplantation, but donor shortage has been a critical limitation. Stem cell injection has been regarded as an alternative to the liver transplantation; yet, there is no optimal condition for such therapy. Moreover, the efficiency of delivery is below 10%, and the efficacy is reported to be minimal or even none. Therefore, we developed a liver patch, which is a 3D cell printed patch-type stem cell therapy with liver decellularized extracellular matrix (LdECM) bioink and human bone marrow derived mesenchymal stem cell to enhance the efficacy and delivery efficiency. The liver patch showed in vitro efficacy in the inactivation of the activated hepatic stellate cell (aHSC) by paracrine effect in transwell coculture condition. For in vivo efficacy assessment, the liver patch was implanted to the pathological liver tissue of irreversible cirrhosis mouse models. The deposited endogenous collagen was significantly decreased, and aHSCs were inactivated in the liver patch delivered cirrhosis model. Consequently, the results demonstrated that the liver patch with functional LdECM bioink and stem cell would be an effective therapy for liver cirrhosis treatment.1

Oncologic safety of skin-sparing mastectomy followed by immediate reconstruction in young patients with breast cancer

Summary: Backgrounds: This study aimed to compare the oncologic outcomes of nipple-sparing mastectomy (NSM)/skin-sparing mastectomy (SSM) followed by immediate reconstruction with those of conventional mastectomy (CM) in young patients aged under 35 years old with breast cancer. Methods: We analyzed retrospectively 2889 patients who underwent mastectomy for breast cancer at Asan Medical Center from January 2003 to December 2008. We compared NSM/SSM followed by immediate reconstruction with CM in patients under 35 years old by analyzing clinicopathologic features, breast cancer specific survival rate (BCSS), distant metastasis free survival rate (DMFS), and local recurrence rate (LRR). Results: Out of a total of 2889 patients, we performed NSM/SSM in 118 patients and CM in 141 patients aged less than 35 years old. DMFS were 85.3% and 73.4% in NSM/SSM and CM, respectively (p = 0.001). BCSS were 90.7% and 73.0% in NSM/SSM and CM, respectively (p = 0.001). After adjusting for stage, there were no statistically significant differences between the two groups with respect to DMFS and BCSS. The type of surgery was not a prognostic factor in multivariate analysis for DMFS and BCSS (CM vs. NSM/SSM: DMFS HR = 0.67, p = 0.215; BCSS: HR = 0.66, p = 0.265). Conclusions: Compared to CM, NSM/SSM followed by immediate breast reconstruction is oncologically safe and could be a viable surgical treatment in young patients under 35 years old with breast cancer. Keywords: Breast neoplasm, Mastectomy, Reconstruction, Young ag

Systems approach to characterize the metabolism of liver cancer stem cells expressing CD133

Liver cancer stem cells (LCSCs) have attracted attention because they cause therapeutic resistance in hepatocellular carcinoma (HCC). Understanding the metabolism of LCSCs can be a key to developing therapeutic strategy, but metabolic characteristics have not yet been studied. Here, we systematically analyzed and compared the global metabolic phenotype between LCSCs and non-LCSCs using transcriptome and metabolome data. We also reconstructed genome-scale metabolic models (GEMs) for LCSC and non-LCSC to comparatively examine differences in their metabolism at genome-scale. We demonstrated that LCSCs exhibited an increased proliferation rate through enhancing glycolysis compared with non-LCSCs. We also confirmed that MYC, a central point of regulation in cancer metabolism, was significantly up-regulated in LCSCs compared with non-LCSCs. Moreover, LCSCs tend to have less active fatty acid oxidation. In this study, the metabolic characteristics of LCSCs were identified using integrative systems analysis, and these characteristics could be potential cures for the resistance of liver cancer cells to anticancer treatments