Optimal set of grid size and angular increment for practical dose calculation using the dynamic conformal arc technique: a systematic evaluation of the dosimetric effects in lung stereotactic body radiation therapy

Purpose To recommend the optimal plan parameter set of grid size and angular increment for dose calculations in treatment planning for lung stereotactic body radiation therapy (SBRT) using dynamic conformal arc therapy (DCAT) considering both accuracy and computational efficiency. Materials and methods Dose variations with varying grid sizes (2, 3, and 4 mm) and angular increments (2°, 4°, 6°, and 10°) were analyzed in a thorax phantom for 3 spherical target volumes and in 9 patient cases. A 2-mm grid size and 2° angular increment are assumed sufficient to serve as reference values. The dosimetric effect was evaluated using dose–volume histograms, monitor units (MUs), and dose to organs at risk (OARs) for a definite volume corresponding to the dose–volume constraint in lung SBRT. The times required for dose calculations using each parameter set were compared for clinical practicality. Results Larger grid sizes caused a dose increase to the structures and required higher MUs to achieve the target coverage. The discrete beam arrangements at each angular increment led to over- and under-estimated OARs doses due to the undulating dose distribution. When a 2° angular increment was used in both studies, a 4-mm grid size changed the dose variation by up to 3–4% (50 cGy) for the heart and the spinal cord, while a 3-mm grid size produced a dose difference of \u3c1% (12 cGy) in all tested OARs. When a 3-mm grid size was employed, angular increments of 6° and 10° caused maximum dose variations of 3% (23 cGy) and 10% (61 cGy) in the spinal cord, respectively, while a 4° increment resulted in a dose difference of \u3c1% (8 cGy) in all cases except for that of one patient. The 3-mm grid size and 4° angular increment enabled a 78% savings in computation time without making any critical sacrifices to dose accuracy. Conclusions A parameter set with a 3-mm grid size and a 4° angular increment is found to be appropriate for predicting patient dose distributions with a dose difference below 1% while reducing the computation time by more than half for lung SBRT using DCAT

Preparation and Characterization of Self-Emulsified Docetaxel

The aim of this paper was to prepare a self-microemulsifying docetaxel (Dtx) using PLGA, Tetraglycol, Labrasol, and Cremophor ELP. The prepared Dtx-loaded self-microemulsifying system (SMES) showed the initial size of the range of 80–100 nm with narrow size distribution and the negative zeta-potential values. Its morphology was a spherical shape by atomic force microscopy. In experiment of stability, Dtx-loaded SMES prepared in DW and BSA condition showed good stability at 37∘C for 7 days. The viability of the B16F10 cells incubated with Dtx-loaded SMES, Dtx-solution, and Taxol were decreased as a function of incubation time. In conclusion, we confirmed that Dtx-loaded SMES showed an inhibitory effect for proliferation of B16F10 melanoma cells

The effect of hidden female smoking on the relationship between smoking and cardiovascular disease

Background: Smoking is a known risk factor for cardiovascular morbidity and mortality, but several Korean studies have shown differing results on the association of current smoking status and the risk of cardiovascular disease (CVD). The aim of the present study was to investigate the association between smoking status and CVD (myocardial infarction and stroke) using national representative populationbased samples. The aim was also to investigate the effects of hidden smokers on the association between CVD and smoking.Methods: Data were acquired from 28,620 participants (12,875 men and 15,745 women), age 19 years or older, who participated in the Korea National Health and Nutrition Examination Survey (KNHANES) conducted from 2008 to 2016.Results: The multivariable logistic regression analysis showed that ex-smoking status was correlated with CVD when self-reported (odds ratio [OR]: 1.62; 95% confidence interval [CI]: 1.20–2.19) and for survey-cotinine verified-smoking status (OR: 1.57; 95% CI: 1.20–2.19). Interestingly, the present study showed current smoking was not significantly associated with CVD. For the effect of sex on smoking and CVD, self-reported and survey-cotinine-verified ex-smoking status were correlated with CVD in males (OR: 1.45; 95% CI: 1.04–2.04 and OR: 1.43; 95% CI: 1.02–2.02) and in females (OR: 2.74; 95% CI: 1.59–4.71 and OR: 2.92; 95% CI: 1.64–5.18). The ratios of cotinine-verified to self-reported smoking rates were 1.95 for women and 1.08 for men.Conclusions: In the current study, while ex-smoking status was significantly associated with CVD, current smoking status was not. Female ex-smoking status had a higher adjusted odds ratio for CVD than males compared to non-smoking status. An effect of hidden female smoking was also found on the association between smoking status and CVD in Korean adults

Exploratory, cognitive, and depressive-like behaviors in adult and pediatric mice exposed to controlled cortical impact

Objective Sequelae of behavioral impairments associated with human traumatic brain injury (TBI) include neurobehavioral problems. We compared exploratory, cognitive, and depressive-like behaviors in pediatric and adult male mice exposed to controlled cortical impact (CCI). Methods Pediatric (21 to 25 days old) and adult (8 to 12 weeks old) male C57Bl/6 mice underwent CCI at a 2-mm depth of deflection. Hematoxylin and eosin staining was performed 3 to 7 days after recovery from CCI, and injury volume was analyzed using ImageJ. Neurobehavioral characterization after CCI was performed using the Barnes maze test (BMT), passive avoidance test, open-field test, light/dark test, tail suspension test, and rotarod test. Acutely and subacutely (3 and 7 days after CCI, respectively), CCI mice showed graded injury compared to sham mice for all analyzed deflection depths. Results Time-dependent differences in injury volume were noted between 3 and 7 days following 2-mm TBI in adult mice. In the BMT, 2-mm TBI adults showed spatial memory deficits compared to sham adults (P<0.05). However, no difference in spatial learning and memory was found between sham and 2-mm CCI groups among pediatric mice. The open-field test, light/dark test, and tail suspension test did not reveal differences in anxiety-like behaviors in both age groups. Conclusion Our findings revealed a graded injury response in both age groups. The BMT was an efficient cognitive test for assessing spatial/non-spatial learning following CCI in adult mice; however, spatial learning impairments in pediatric mice could not be assessed

Development of an approximate construction duration prediction model during the project planning phase for general office buildings

Accurate prediction of the construction duration is imperative to the reliable cash flow analysis during the project planning phase when feasibility analysis is carried out. However, lack of information and frequent changes that occur as a result of a negotiation process between the owner and the designer in defining the project scope make it difficult to compute real-time construction duration. Domestic and foreign models for calculating the construction durations cannot be readily applied to computation of construction duration for general office buildings in Korea specifically during the project planning phase as there is a limit in its applicability due to numerous restrictions. Moreover, there are no preceding studies suggesting different computational approaches to predict the entire construction duration for office buildings with the approximate construction duration concept during planning phase. Therefore, based on the collected performance data, this study proposes a multiple linear regression model that facilitates reliable prediction of approximate construction duration for office buildings in the project planning phase. The model will allow the owner and other stakeholders to predict the real-time construction duration using the basic information on office buildings and to assess the construction durations incorporating frequent changes during the project planning phase

Signet Ring Cell Carcinoma Arising from a Solitary Juvenile Polyp in the Colon

Juvenile polyps are relatively common polyps that affect predominantly young patients and may occur in isolated, multiple, and/or familial forms. They have been considered to be benign lesions without neoplastic potential, but for patients with multiple juvenile polyposis, the cumulative malignant risk is greater than fifty percents. In patients with a solitary polyp, the risks are minimal, and only a few cases of malignant change from a solitary juvenile polyp have been reported. We describe the case of a twenty one year old female with one solitary juvenile polyp, which contained a signet ring cell carcinoma in the mucosal layer

Ubiquitous-Severance Hospital Project: Implementation and Results

OBJECTIVES: The purpose of this study was to review an implementation of u-Severance information system with focus on electronic hospital records (EHR) and to suggest future improvements. METHODS: Clinical Data Repository (CDR) of u-Severance involved implementing electronic medical records (EMR) as the basis of EHR and the management of individual health records. EHR were implemented with service enhancements extending to the clinical decision support system (CDSS) and expanding the knowledge base for research with a repository for clinical data and medical care information. RESULTS: The EMR system of Yonsei University Health Systems (YUHS) consists of HP integrity superdome servers using MS SQL as a database management system and MS Windows as its operating system. CONCLUSIONS: YUHS is a high-performing medical institution with regards to efficient management and customer satisfaction; however, after 5 years of implementation of u-Severance system, several limitations with regards to expandability and security have been identifiedope

The Effects of Glyburide on Apoptosis and Endoplasmic Reticulum Stress in INS-1 Cells in a Glucolipotoxic Condition

Backgroundβ-cell death due to endoplasmic reticulum (ER) stress has been regarded as an important pathogenic component of type 2 diabetes. The possibility has been suggested that sulfonylurea, currently being used as one of the main oral hypoglycemic agents of type 2 diabetes, increases ER stress, which could lead to sulfonylurea failure. The authors of the present study examined ER stress of β-cells in a glucolipotoxic condition using glyburide (GB) in an environment mimicking type 2 diabetes.MethodsApoptosis was induced by adding various concentrations of GB (0.001 to 200 µM) to a glucolipotoxic condition using 33 mM glucose, and the effects of varied concentrations of palmitate were evaluated via annexin V staining. The markers of ER stress and pro-apoptotic markers were assessed by Western blotting and semi-quantitative reverse transcription-polymerase chain reaction. Additionally, the anti-apoptotic markers were evaluated.ResultsAddition of any concentration of GB in 150 µM palmitate and 33 mM glucose did not increase apoptosis. The expression of phosphorylated eukaryotic initiation factor (eIF-2α) was increased and cleaved caspase 3 was decreased by adding GB to a glucolipotoxic condition. However, other ER stress-associated markers such as Bip-1, X-box binding protein-1, ATF-4 and C/EBP-homologous protein transcription factor and anti-apoptotic markers phosphor-p85 phosphatidylinositol 3-kinase and phosphorylation of Akt did not change significantly.ConclusionGB did not show further deleterious effects on the degree of apoptosis or ER stress of INS-1 cells in a glucolipotoxic condition. Increased phosphorylation of eIF-2α may attenuate ER stress for adaptation to increased ER protein load