Purpose: High-dose radiotherapy (RT) for localized prostate cancer requires careful consideration of target position changes and adjacent organs-at-risk (OARs), such as the rectum and bladder. Therefore, daily monitoring of target position and OAR changes is crucial in minimizing interfractional dosimetric uncertainties. For efficient monitoring of the internal condition of patients, we assessed the feasibility of an auto-segmentation of OARs on the daily acquired images, such as megavoltage computed tomography (MVCT), via a commercial artificial intelligence (AI)-based solution in this study. Materials and Methods: We collected MVCT images weekly during the entire course of RT for 100 prostate cancer patients treated with the helical TomoTherapy system. Based on the manually contoured body outline, the bladder including prostate area, and rectal balloon regions for the 100 MVCT images, we trained the commercially available fully convolutional (FC)-DenseNet model and tested its auto-contouring performance. Results: Based on the optimally determined hyperparameters, the FC-DenseNet model successfully auto-contoured all regions of interest showing high dice similarity coefficient (DSC) over 0.8 and a small mean surface distance (MSD) within 1.43 mm in reference to the manually contoured data. With this well-trained AI model, we have efficiently monitored the patient's internal condition through six MVCT scans, analyzing DSC, MSD, centroid, and volume differences. Conclusion We have verified the feasibility of utilizing a commercial AI-based model for auto-segmentation with low-quality daily MVCT images. In the future, we will establish a fast and accurate auto-segmentation and internal organ monitoring system for efficiently determining the time for adaptive replanning.

Aldose reductase (AR) protein, a member of the NADPH-dependent aldo-keto reductase family, reduces a wide range of aldehydes and enhances cell survival by inhibition of oxidative stress. Oxidative stress is known as one of the major pathological factor in ischemia. Since the precise function of AR protein in ischemic injury is fully unclear, we examined the function of AR protein in hippocampal neuronal (HT-22) cells and in an animal model of ischemia in this study. Cell permeable Tat-AR protein was produced by fusion of protein transduction domain in Tat for delivery into the cells. Tat-AR protein transduced into HT-22 cells and significantly inhibited cell death and regulated the mitogen-activate protein kinases (MAPKs), Bcl-2, Bax, and Caspase-3 under oxidative stress condition. In an ischemic animal model, Tat-AR protein transduced into the brain tissues through the blood-brain barrier (BBB) and drastically decreased neuronal cell death in hippocampal CA1 region. These results indicate that transduced Tat-AR protein has protective effects against oxidative stress-induced neuronal cell death in vitro and in vivo, suggesting that Tat-AR protein could be used as potential therapeutic agent in ischemic injury.
Aldehyde Reductase ; Aldehydes ; Blood-Brain Barrier ; Brain ; CA1 Region, Hippocampal ; Caspase 3 ; Cell Death ; Cell Survival ; Humans ; In Vitro Techniques ; Ischemia ; Models, Animal ; Neurons ; Oxidative Stress ; Oxidoreductases ; Protein Kinases

PURPOSE: We describe the daily bladder volume change observed by mega-voltage computed tomography (MVCT) during pelvic radiotherapy with potential predictors of increased bladder volume variations. MATERIALS AND METHODS: For 41 patients who received pelvic area irradiation, the volumes of bladder and pelvic body contour were measured twice a day with pre- and post-irradiation MVCT from the 1st to the 10th fraction. The median prescription dose was 20 Gy (range, 18 to 30 Gy) up to a 10th fraction. The upper and lower margin of MVCT scanning was consistent during the daily treatments. The median age was 69 years (range, 33 to 86 years) and 10 patients (24.4%) were treated postoperatively. RESULTS: Overall bladder volume on planning computed tomography was 139.7 ± 92.8 mL. Generally, post-irradiation bladder volume (POSTBV) was larger than pre-irradiation bladder volume (PREBV) (p < 0.001). The mean PREBV and POSTBV was reduced after 10 fraction treatments by 21.3% (p = 0.028) and 25.4% (p = 0.007), respectively. The MVCT-scanned body contour volumes had a tendency to decrease as the treatment sessions progressed (p = 0.043 at the 8th fraction and p = 0.044 at the 10th fraction). There was a statistically significant correlation between bladder filling time and PREBV (p = 0.001). CONCLUSION: Daily MVCT-based bladder volume assessment was feasible both intra- and inter-fractionally.
Humans ; Pelvic Neoplasms ; Prescriptions ; Radiotherapy ; Radiotherapy, Intensity-Modulated ; Urinary Bladder

Background: Controlled-release oxycodone/naloxone (OXN-CR) maintains the effect of opioid-induced analge-sia through oxycodone while reducing the occurrence rate of opioid-induced constipation through naloxone. The present study was designed to assess the non-inferiority of OXN-CR to controlled-release oxycodone (OX-CR) for the control of cancer-related pain in Korean patients. Methods: In this randomized, open-labeled, parallel-group, phase IV study, we enrolled patients aged 20 years or older with moderate to severe cancer-related pain [numeric rating scale (NRS) pain score≥4] from seven Korean oncology/hematology centers. Patients in the intention-to-treat (ITT) population were randomized (1:1) to OXN-CR or OX-CR groups. OXN-CR was administered starting at 20 mg/10 mg per day and up-titrated to a maximum of 80 mg/40 mg per day for 4 weeks, and OX-CR was administered starting at 20 mg/day and up-titrated to a maximum of 80 mg/day for 4 weeks. The primary efficacy endpoint was the change in NRS pain score from baseline to week 4, with non-inferiority margin of?1.5. Secondary endpoints included analgesic rescue medication intake, patient-reported change in bowel habits, laxative intake, quality of life (QoL), and safety assessments. Results: Of the ITT population comprising 128 patients, 7 with missing primary efficacy data and 4 who violated the eligibility criteria were excluded from the efficacy analysis. At week 4, the mean change in NRS pain scores was not significantly different between the OXN-CR group (n= 58) and the OX-CR group (n= 59) (?1.586 vs.?1.559, P= 0.948). The lower limit of the one-sided 95％ confidence interval (?0.776 to 0.830) for the difference exceeded the non-inferiority margin (P < 0.001). The OXN-CR and OX-CR groups did not differ significantly in terms of analgesic rescue medication intake, change in bowel habits, laxative intake, QoL, and safety assessments. Conclusions: OXN-CR was non-inferior to OX-CR in terms of pain reduction after 4 weeks of treatment and had a similar safety profile. Studies in larger populations of Korean patients with cancer-related pain are needed to further investigate the effectiveness of OXN-CR for long-term pain control and constipation alleviation.

BACKGROUND/AIMS: Noncardiac chest pain (NCCP) is substernal, squeezing chest pain, unrelated to the cardiac problem. Our study aimed to define the prevalence and clinical characteristics of reflux esophagitis in NCCP patients in Korea. MATERIALS AND METHODS: We reviewed medical records of patients who visited Department of Cardiology, St. Paul's Hospital due to chest pain and had normal coronary arteriography and who had received endoscopy within 6 months. Patients diagnosed with peptic ulcer or gastric cancer were excluded. The patients were classified into two groups according to their endoscopic results; the reflux esophagitis group and the control group. RESULTS: Two hundred seventeen NCCP patients were enrolled and 96 patients (44.2%) were diagnosed with reflux esophagitis: 68 patients (31.3%) with minimal change esophagitis; 26 patients (12.0%) with Los Angeles (LA) grade A; 2 patients (0.9%) with LA grade B. There were no patients with severe erosive reflux disease. There were no significantly different characteristics in the reflux esophagitis group and the control group. CONCLUSIONS: The prevalence of reflux esophagitis in NCCP patients in Korea was 44.2%. Most patients had mild reflux esophagitis.
Angiography ; Cardiology ; Chest Pain* ; Endoscopy ; Esophagitis ; Esophagitis, Peptic* ; Gastroesophageal Reflux ; Humans ; Korea* ; Medical Records ; Peptic Ulcer ; Prevalence* ; Stomach Neoplasms ; Thorax*

Recent cohort studies have relied on exposure prediction models to estimate individual-level air pollution concentrations because individual air pollution measurements are not available for cohort locations. For such prediction models, geographic variables related to pollution sources are important inputs. We demonstrated the computation process of geographic variables mostly recorded in 2010 at regulatory air pollution monitoring sites in South Korea. On the basis of previous studies, we finalized a list of 313 geographic variables related to air pollution sources in eight categories including traffic, demographic characteristics, land use, transportation facilities, physical geography, emissions, vegetation, and altitude. We then obtained data from different sources such as the Statistics Geographic Information Service and Korean Transport Database. After integrating all available data to a single database by matching coordinate systems and converting non-spatial data to spatial data, we computed geographic variables at 294 regulatory monitoring sites in South Korea. The data integration and variable computation were performed by using ArcGIS version 10.2 (ESRI Inc., Redlands, CA, USA). For traffic, we computed the distances to the nearest roads and the sums of road lengths within different sizes of circular buffers. In addition, we calculated the numbers of residents, households, housing buildings, companies, and employees within the buffers. The percentages of areas for different types of land use compared to total areas were calculated within the buffers. For transportation facilities and physical geography, we computed the distances to the closest public transportation depots and the boundary lines. The vegetation index and altitude were estimated at a given location by using satellite data. The summary statistics of geographic variables in Seoul across monitoring sites showed different patterns between urban background and urban roadside sites. This study provided practical knowledge on the computation process of geographic variables in South Korea, which will improve air pollution prediction models and contribute to subsequent health analyses.
Air Pollution* ; Altitude ; Buffers ; Cohort Studies ; Family Characteristics ; Geographic Information Systems ; Geography ; Housing ; Information Services ; Korea* ; Seoul ; Transportation

Recent cohort studies have relied on exposure prediction models to estimate individual-level air pollution concentrations because individual air pollution measurements are not available for cohort locations. For such prediction models, geographic variables related to pollution sources are important inputs. We demonstrated the computation process of geographic variables mostly recorded in 2010 at regulatory air pollution monitoring sites in South Korea. On the basis of previous studies, we finalized a list of 313 geographic variables related to air pollution sources in eight categories including traffic, demographic characteristics, land use, transportation facilities, physical geography, emissions, vegetation, and altitude. We then obtained data from different sources such as the Statistics Geographic Information Service and Korean Transport Database. After integrating all available data to a single database by matching coordinate systems and converting non-spatial data to spatial data, we computed geographic variables at 294 regulatory monitoring sites in South Korea. The data integration and variable computation were performed by using ArcGIS version 10.2 (ESRI Inc., Redlands, CA, USA). For traffic, we computed the distances to the nearest roads and the sums of road lengths within different sizes of circular buffers. In addition, we calculated the numbers of residents, households, housing buildings, companies, and employees within the buffers. The percentages of areas for different types of land use compared to total areas were calculated within the buffers. For transportation facilities and physical geography, we computed the distances to the closest public transportation depots and the boundary lines. The vegetation index and altitude were estimated at a given location by using satellite data. The summary statistics of geographic variables in Seoul across monitoring sites showed different patterns between urban background and urban roadside sites. This study provided practical knowledge on the computation process of geographic variables in South Korea, which will improve air pollution prediction models and contribute to subsequent health analyses.
Air Pollution* ; Altitude ; Buffers ; Cohort Studies ; Family Characteristics ; Geographic Information Systems ; Geography ; Housing ; Information Services ; Korea* ; Seoul ; Transportation

BACKGROUND/AIMS: Effective bowel preparation is essential for accurate diagnosis of colon disease. We investigated efficacy and safety of 2 L polyethylene glycol (PEG) solution with 90 mL sodium phosphate (NaP) solution compared with 4 L PEG method. METHODS: Between August 2009 and April 2010, 526 patients were enrolled who visited Seoul National University Bundang Hospital for colonoscopy. We allocated 249 patients to PEG 4 L group and 277 patients to PEG 2 L with NaP 90 mL group. Detailed questionnaires were performed to investigate compliance, satisfaction and preference of each method. Bowel preparation quality and segmental quality were evaluated. Success was defined as cecal intubation time less than 20 minutes without any help of supervisors. RESULTS: Both groups revealed almost the same baseline characteristics except the experience of operation. PEG 4 L group's compliance was lower than PEG 2 L with NaP 90 mL group. Success rate and cecal intubation time was not different between two groups. Overall bowel preparation quality of PEG 2 L with NaP 90 mL group was better than PEG 4 L group. Segmental bowel preparation quality of PEG 2 L with NaP 90 mL group was also better than PEG 4 L group in all segments, especially right side colon. Occurrence of hyperphosphatemia was higher in PEG 2 L with NaP 90 mL group than PEG 4 L group. However, significant adverse event was not reported. CONCLUSIONS: PEG 2 L with NaP 90 mL method seems to be more effective bowel preparation than PEG 4 L method.
Administration, Oral ; Adult ; Aged ; Colonic Diseases/diagnosis ; Colonoscopy/*methods ; Humans ; Male ; Middle Aged ; Patient Compliance ; Phosphates/*administration & dosage ; Polyethylene Glycols/*administration & dosage ; Questionnaires ; Solutions ; Therapeutic Irrigation

BACKGROUND/AIMS: The use of self-expandable metal stents (SEMS) is a safe and efficacious method for palliating malignant gastric outlet obstruction. However, few reports have assessed clinical outcome after the insertion of SEMS for malignant gastric outlet obstruction caused by stomach cancer. The aim of this study was to assess the usefulness of uncovered SEMS in patients with malignant gastric outlet obstruction caused by stomach cancer. METHODS: We evaluated 62 patients with gastric outlet obstruction caused by stomach cancer treated by the implantation of uncovered SEMS. A total of 62 patients (43 males, 19 females) were treated between August 2000 and March 2007. A scoring system was used to grade the ability to eat. RESULTS: Stent implantation was successful in 61 (98.4%) patients. Relief of obstructive symptoms was achieved in 49 (80.3%) patients. The mean survival duration was 143 days. The mean stent patency time was 103.5 days. An improvement in the ability to eat using the scoring system was statistically significant (p<0.05). CONCLUSIONS: Endoscopic placement of uncovered SEMS is a safe and effective treatment for the palliation of patients with inoperable malignant gastric outlet obstruction caused by stomach cancer.
Gastric Outlet Obstruction ; Humans ; Male ; Stents ; Stomach ; Stomach Neoplasms

BACKGROUND/AIMS: Palliative endoscopic or percutaneous internal drainage is widely used for treating hilar cholangiocarcinoma. Yet unilateral biliary drainage does not completely improve jaundice and it can induce acute cholangitis by the undrained contrast media. To investigate this technique's technical and clinical effectiveness, a newly devised Y-configured dual stent was used for treating advanced hilar malignancies. METHODS: From May, 2005 to May, 2007, 20 hilar malignancies (men: women=9:11, age=70.5 yr) that were not suitable for surgical resection were included in this study. For bilateral metal stent placement, a biliary stent with a wide open central mesh was first inserted. After this, another stent without a hole was inserted into the contralateral hepatic duct through the open central mesh of the first stent. RESULTS: Bilateral metal stent insertion was done in 14 of 20 patients. Among the 14 patients in whom bilateral stents were successfully placed, the rate of functional success was 100%. There were no early complications. As a late complication, stent occlusion occurred in 4 of 14 patients (28.5%), and one of these patients had a plastic stent inserted. The other 3 patients were treated with percutaneous transhepatic biliary drainage. The median stent patency period was 231 days. CONCLUSION: The bilateral metal stent method using the Y stent is safe and effective for bilateral biliary drainage in patients with unresectable hilar malignancies.
Cholangiocarcinoma ; Cholangitis ; Contrast Media ; Drainage ; Hepatic Duct, Common ; Humans ; Jaundice ; Plastics ; Stents