1.Real-Time Computed Tomography Volume Visualization with Ambient Occlusion of Hand-Drawn Transfer Function Using Local Vicinity Statistic
Jaewoo KIM ; Taejun HA ; Heewon KYE
Healthcare Informatics Research 2019;25(4):297-304
OBJECTIVES: In this paper, we present an efficient method to visualize computed tomography (CT) datasets using ambient occlusion, which is a global illumination technique that adds depth cues to the output image. We can change the transfer function (TF) for volume rendering and generate output images in real time. METHODS: In preprocessing, the mean and standard deviation of each local vicinity are calculated. During rendering, the ambient light intensity is calculated. The calculation is accelerated on the assumption that the CT value of the local vicinity of each point follows the normal distribution. We approximate complex TF forms with a smaller number of connected line segments to achieve additional acceleration. Ambient occlusion is combined with the existing local illumination technique to produce images with depth in real time. RESULTS: We tested the proposed method on various CT datasets using hand-drawn TFs. The proposed method enabled real-time rendering that was approximately 40 times faster than the previous method. As a result of comparing the output image quality with that of the conventional method, the average signal-to-noise ratio was approximately 40 dB, and the image quality did not significantly deteriorate. CONCLUSIONS: When rendering CT images with various TFs, the proposed method generated depth-sensing images in real time.
Acceleration
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Computer Systems
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Cues
;
Dataset
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Lighting
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Mathematical Computing
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Methods
;
Signal-To-Noise Ratio
3.Growth and clinical efficacy of fortified human milk and premature formula on very low birth weight infants.
Heewon CHUEH ; Myo Jing KIM ; Young A LEE ; Jin A JUNG
Korean Journal of Pediatrics 2008;51(7):704-712
PURPOSE: A prospective, controlled trial was conducted to evaluate growth, efficacy, safety and nutritional status for very low birth weight infants fed with human milk fortified with Maeil human milk fortifier (Maeil HMF(R); Maeil Dairies Co., Ltd.). METHODS: We enrolled 45 premature infants with a birth weight <1,500 g and gestational age <33 weeks, who were born at Dong-A University Hospital from October, 2006 through December, 2007. They were divided into 2 groups: infants in one group were fed with human milk fortified with HMF(R), and the second were fed with preterm formula. Growth, biochemical indices, feeding tolerance, and other adverse events in each group were assessed serially and compared relatively. Follow-up data were also collected after discharge at 1, 3, and 6 months corrected age. RESULTS: Characteristics of the 2 groups including average gestational age, birth weight, sex, respiratory distress syndrome, patent ductus arteriosus, and other adverse events (sepsis, retinopathy of prematurity, and intraventricular hemorrhage) showed no significant difference. Average feeding start day (8.00+/-3.27 d vs. 8.86+/-5.37 d) (P=0.99) and the number of days required to reach full feeding after start feeding (41.78+/-20.47 d vs 36.86+/-20.63 d) (P=0.55) were not significantly different in the group fed human milk fortified with HMF(R) when compared with the group that was fed preterm formula. The duration of total parenteral nutrition and the incidence of feeding intolerance also showed no differences between the 2 groups. Although infants fed with human milk fortified with HMF(R) showed faster weight gain than those fed with preterm formula at the end stage of the admission period, other growth indices of the two groups showed no significant difference. No significant correlations were found between the 2 groups with regard to weight gain velocity, height gain velocity, head circumference velocity, and post- discharge follow up growth indices. CONCLUSION: Premature infants fed human milk fortified with HMF(R) showed no significant difference compared with those fed preterm formula in growth, biochemical indices, and adverse events. Using human milk fortifier can be an alternative choice for very low birth weight infants, who need high levels nutritional support even after discharge from NICU.
Birth Weight
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Ductus Arteriosus, Patent
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Follow-Up Studies
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Gestational Age
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Head
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Humans
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Incidence
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Infant
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Infant, Newborn
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Infant, Premature
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Infant, Very Low Birth Weight
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Milk, Human
;
Nutritional Status
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Nutritional Support
;
Parenteral Nutrition, Total
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Prospective Studies
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Retinopathy of Prematurity
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Weight Gain
4.A case of acute respiratory distress syndrome associated with congenital H-type tracheoesophageal fistula and gastroesophageal reflux.
Heewon CHUEH ; Myo Jing KIM ; Jin A JUNG
Korean Journal of Pediatrics 2008;51(8):892-895
H-type tracheoesophageal fistula (TEF) is extremely rare in infants and children, and clinical manifestations of this condition are diverse based on its severity. Some cases of congenital TEF diagnosed in adulthood have been reported, which indicate the difficulty of early diagnosis of this disease. Gastroesophageal reflux (GER) may induce chronic aspiration, pulmonary aspiration, apparent life-threatening events, and failure to thrive. We report a 5-month- old boy whose recurrent pneumonia and wheezing did not improve under usual treatment and led to acute respiratory distress syndrome. He was found to have severe GER on the second-trial of the esophagogram and was eventually revealed to have congenital H-type TEF upon repeated evaluation.
Child
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Early Diagnosis
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Failure to Thrive
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Gastroesophageal Reflux
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Humans
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Infant
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Pneumonia
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Respiratory Distress Syndrome, Adult
;
Respiratory Sounds
;
Tracheoesophageal Fistula
5.The Long-Term Outcomes of Alzheimer’s Disease Patients Treated with Anti-Dementia Medications According to Baseline Dementia Severity
Heewon SEO ; Yuri PARK ; Insun KWON ; Jeong Lan KIM
Journal of the Korean Society of Biological Therapies in Psychiatry 2021;27(1):33-39
Objectives:
:To describe the differences in long-term outcomes in Alzheimer’s disease (AD) patients according to initial dementia severity.
Methods:
:A retrospective chart review of AD patients from a dementia clinic at the University Hospital in Korea was conducted from April 2010 to March 2017. There were 168 patients enrolled, who were divided into three groups based on initial Clinical Dementing Rating (CDR). There were 55 in the very mild group (CDR=0.5 ; mean age 80.64±6.57), 93 in the mild group (CDR=1 ; mean age 80.57±7.28) and 20 in the moderate group (CDR=2 ; mean age 83.00±9.07). Participants were treated with donepezil±memantine. The observation period was 2.44±0.50 years. Cognitive function and severity of dementia were initially assessed by the Consortium to Establish a Registry for Alzheimer’s Disease Neuropsychological Assessment Battery (CERAD-NP) and were annually assessed by Mini-Mental State Exam (MMSE), CDR and CDR-Sum of boxes (CDR-SB).
Results:
:The annual decline rate of MMSE score was -0.82 and those of very mild, mild, moderate groups were -0.63, -0.80, -1.96 respectively, while the annual change in CDR-SB score was 0.98, very mild group 0.86, mild group 1.03, moderate group 1.26. Education level, male, initial CDR were found to be significant potential factors in the annual change in MMSE, while initial CDR was a significant potential factor in the annual change in CDR-SB.
Conclusion
:It is meaningful that we studied long-term outcomes of anti-dementia medications in real-world clinical setting. The higher the initial severity of AD, the higher the cognitive decline rate.
6.The Effects of Dietary Interventions on mRNA Expression of Peroxisome Proliferator Activated Receptor Isoforms (PPAR Isoforms)in Rat Skeletal Muscle.
Jangkyu LEE ; Jungkyu KIM ; Heewon MOON ; Youngoh SHIN ; Jongsam LEE
The Korean Journal of Nutrition 2007;40(3):221-228
We determined the effects of dietary manipulations on messenger RNA of peroxisome proliferators activated receptor isoforms (i.e., PPAR alpha, beta/delta, gamma)in red vastus lateralis muscle of rats. Total 16 male Sprague-Dawley rats were used, and animals were divided into one of two dietary conditions :either chow diet group (CHOW ;n =8 )in which animals were fed with standard rodent chow (61.8% carbohydrate, 15.7% fat, 22.5% protein )or high fat diet group (FAT n =8 ) in which animals were fed 24.3% carbohydrate, 52.8% fat, 22.9% protein. At the end of the 8 weeks of experimental pe-riod, red vastus lateralis muscle was dissected out from all animals, and PPAR alpha, beta/delta, gamma mRNA expression was deter-mined. There was no significant difference in body mass (BM )between CHOW and FAT. As expected, blood glucose and free fatty acid (FFA )concentration was higher in FAT than CHOW (p <0.05 ), and lactate concentration was significan-tly lower in FAT compared to CHOW (p <0.05 ). Insulin concentration tended to higher in FAT than CHOW (67.2 +/- 21.9 vs. 27.0 +/-5.2 pmol/L ), but it did not reach to the statistical significance. Gene expression of PPAR alpha was not signifi-cantly different between CHOW and FAT. It was not also significantly different in PPAR beta/delta. Interestingly, expression of mRNA in PPAR gamma however, was markedly depressed in FAT compared to CHOW (approximately 3 fold higher in CHOW ; p <0.05 ). Results obtained from present study implies that PPAR gamma (as compensatory function of PPAR alpha is expressed ) possibly exerts another major tuning roles in fatty acid transport, utilization, as well as biosynthesis in skeletal muscle cells. The situations and conditions that can be postulated for this implication need to be further examined.
Animals
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Blood Glucose
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Diet
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Diet, High-Fat
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Gene Expression
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Humans
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Insulin
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Lactic Acid
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Male
;
Muscle, Skeletal*
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Peroxisome Proliferator-Activated Receptors
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Peroxisome Proliferators
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Peroxisomes*
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PPAR alpha
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PPAR gamma
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Protein Isoforms*
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Quadriceps Muscle
;
Rats*
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Rats, Sprague-Dawley
;
RNA, Messenger*
;
Rodentia
8.Physiological Roles of Monomeric Amyloid-β and Implications for Alzheimer’s Disease Therapeutics
Hyomin JEONG ; Heewon SHIN ; Seungpyo HONG ; YoungSoo KIM
Experimental Neurobiology 2022;31(2):65-88
Alzheimer’s disease (AD) progressively inflicts impairment of synaptic functions with notable deposition of amyloid-β (Aβ) as senile plaques within the extracellular space of the brain. Accordingly, therapeutic directions for AD have focused on clearing Aβ plaques or preventing amyloidogenesis based on the amyloid cascade hypothesis. However, the emerging evidence suggests that Aβ serves biological roles, which include suppressing microbial infections, regulating synaptic plasticity, promoting recovery after brain injury, sealing leaks in the blood-brain barrier, and possibly inhibiting the proliferation of cancer cells. More importantly, these functions were found in in vitro and in vivo investigations in a hormetic manner, that is to be neuroprotective at low concentrations and pathological at high concentrations. We herein summarize the physiological roles of monomeric Aβ and current Aβ-directed therapies in clinical trials. Based on the evidence, we propose that novel therapeutics targeting Aβ should selectively target Aβ in neurotoxic forms such as oligomers while retaining monomeric Aβ in order to preserve the physiological functions of Aβ monomers.
10.Tobacco consumption, sales, and output as monitoring indicators in the era of the tobacco endgame: a Korean example
Hana KIM ; Hee-kyoung NAM ; Heewon KANG
Epidemiology and Health 2023;45(1):e2023030-
OBJECTIVES:
The consumption, sales, and output of tobacco products each suggest different areas of intervention for tobacco control. In the era of the tobacco endgame, as increasingly stronger supply-side measures are implemented, multifaceted indicators that assess both supply and/or demand are required. We aimed to estimate the consumption of cigarette and heated tobacco products (HTPs) and sought agreement between the various indicators.
METHODS:
The annual cigarette and HTP consumption in 2014-2020 was calculated using the frequency and intensity of cigarette use from representative surveys of adults and adolescents by sex and age. Sales and output data were acquired from governmental sources. Spearman correlation coefficients and Bland–Altman plots were used to compare the indicators.
RESULTS:
Tobacco output, cigarette sales, and cigarette consumption were greatest in 2014. The HTP consumption calculated for 2020 was 292.28 million packs. Cigarette consumption and sales correlated significantly, as did tobacco output and tobacco sales. A Bland–Altman plot comparing the difference between cigarette consumption and sales showed that this difference was largest in 2014, immediately before cigarette prices increased. With the exception of a single year, all cigarette consumption values were within the limits of agreement for cigarette sales and tobacco output.
CONCLUSIONS
Our analyses showed agreement between demand-side (tobacco consumption) and supply-side (sales and output) indicators. We recommend using all indicators to monitor the impacts of tobacco control on both demand and supply sides. The systematic use of various indicators is critical to achieve the end of the tobacco epidemic.