1.Comparison of digital radiometric featuresbetween radicular cysts and periapical granulomas.
Journal of Korean Academy of Oral and Maxillofacial Radiology 1999;29(1):241-254
The purpose of this study was to investigate whether a radiometric analysis of radicular cysts and periapical granulomas is useful in the differential diagnosis. In this experiment, twenty-nine periapical radiographs of the radicular cyst and those periapical granuloma were used. The periapical radiography was taken by intraoral paralleling device. The X-ray film was digitized and digitally filtered to reduce film-grain noise. We estimated density difference of the inner/outer area, roundness or circularity, bone profile or scan line of the margin and cumulative percentage frequency curve of radicular cyst & periapical granuloma. The obtained results were as follows ; 1. The differences in density between ROIs of inner and outer area of radicular cysts were smaller than those of periapical granulomas. 2. The equivalent circular diameter was over 6.3mm, there was significant difference between periapical cyst and periapical granuloma. 3. In differential diagnosis of radicular cyst and periapical granuloma using bone profile, sensitivity, spicificity and accuracy were considerably high(0.83, 0.86, 0.86) respectively. 4. Cumulative percentage frequency curve of the radicular cyst was closer to the pseudo-pixel value of 50 than average curve, whereas periapical granuloma was closer to that of 0. Hence we conclude that digital radiometric features might be useful in the differential diagnosis between radicular cyst and periapical granuloma.
Diagnosis, Differential
;
Noise
;
Periapical Granuloma*
;
Radicular Cyst*
;
Radiography
;
X-Ray Film
2.Effects of taxol and ionizing radiation on cytotoxicity and prostaglandin production in KB, RPMI-2650, SW-13 and L929.
Journal of Korean Academy of Oral and Maxillofacial Radiology 1998;28(1):127-144
The author evaluated the effects of taxol, a microtubular inhibitor, as a possible radiation sensitizer and the production of prostaglandins on three human cancer cell lines(KB, RPMI-2650 and SW-13) and one murine cell line(L929). Each cell line was divided into four groups(control, taxol only, radiation only and combination of taxol and radiation). The treatment consisted of a single irradiation of 10 Gy and graded doses(5, 50, 100, 200, 300, 500 nM) of taxol for a 24-h period. The cytotoxicity of taxol alone was measured at 1 day after(1-day group) and 4 days after(4-day group) the treatment. The survival ratio of cell was analyzed by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-dimethyl tetrazolium bromide) test. Prostaglandins(PGE2 and PGI2) were measured in the culture medium by a radioimmunoassay. The results obtained were as follows ; 1. There was a significantly in creased cytotoxicity of KB cells in 4-day group than those in 1-day group. Therr was a high correlation between doses of taxol and cell viability in both groups(1-day group R=0.82741, 4-day group R=0.84655). 2. There was a significantly increased cytotoxicity of RPMI-2650 cells treated with high concentration of taxol in 4-day group than those in 1-day group. Also there was a high correlation between doses of taxol and cell viability in 4-day group(R=0.93917). 3. There was a significantly increased cytotoxicity of SW-13 cell treated with high concentration of taxol in 4-day group than those in 1-day group. However no high correlation was observed between doses of taxol and cell viability in both groups(1-day group R=0.46362, 4-day group R=0.65425). 4. There was a significantly increased cytotoxicity of L929 cells treated with low concentration of taxol in 4-day group than those in 1-day group. At the same time, there was a low correlation between doses of taxol and cell viability in both groups(1-day group R=0.34237, 4-day group R=0.23381). 5. In 1-day group of L929 cells, higher cytotoxicities were observed in the groups treated with 500 nM taxil than given 10 Gy radiation alone showed a radiosensitizing effect by taxol. 6. In addition to L929 cells, all cancer cells treated with a commbinationof taxol and radiation in 4-day group appeared ti have some fragmented nuclei and to float on the medium. In addition, L929 cells appeared to be more confluent. 7. The level of PGE2 production was the highest in the contol KB cells. This appeared to increase in every experimental group of all three cancer except L929 cells. There was a significantly increased production of PGE2 in SW-13 cells treated with a combination taxol and radiation compared to the other experimental groups. 8. The level of PGI2 production in the contol group RPMI-2650 cells was the highest. This appeared to increase in every experimental group of all cells except in SW-13 cells. This also increased signigicantly in RPMI-2650 cells treated with a cimbination of taxol and radiation compared to the other experimental groups.
Cell Line
;
Cell Survival
;
Dinoprostone
;
Epoprostenol
;
Humans
;
KB Cells
;
Paclitaxel*
;
Prostaglandins
;
Radiation Dosage
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Radiation, Ionizing*
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Radiation-Sensitizing Agents
;
Radioimmunoassay
3.Fractal dimension from radiographs of bone as indicatos of possible osteoporosis.
Journal of Korean Academy of Oral and Maxillofacial Radiology 1998;28(1):17-26
The purpose of this study was to investigate wether a radiographic estimate of osseous fractal dimension is useful in the characterization of structural changes in bone. Ten specimens of bone were progressively decalcified in fresh 50ml solutions of 0.1N hydrochloric acid solution at cummulative timed periods of 5, 10, 20, 30, 60 and 90 minutes, and radiographed from 0 degree projection angle controlled by intraoral parelleling device. The test set of 70 radiographs was digitally filtered to reduce film-grain noise. I performed one-dimensional variance and fractal analysis of bony profiles or scan lines, Correlation analysis quantified the relationship between variance and fractal dimension. The obtained results were as follow ; 1. After the first stage of decalcification variance and fractal dimension of scan line pixel intensities generally decreased with a range of 57.94 to 12.64 and 1.59 to 1.36. 2. Correlation coefficient(r) relating variance to fractal dimension was consistantly excellent(range r=0.90 to 0.98). 3. Variance and fractal dimension were much alike in ability to discriminate, at leat on a group basis, between contrl and decalcified specimens.
Fractals*
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Hydrochloric Acid
;
Noise
;
Osteoporosis*
4.Comparison of digitized radiographic alveolar features with age.
Journal of Korean Academy of Oral and Maxillofacial Radiology 1997;27(1):17-24
The purpose of the present stydy was to use digital profile image features and digital imge analysis of fixed-dime nsion bone regions, extracted from standardized periapical radiographs of the maxilla, to determine whether differences exist in alveolar bone of younger women(mean age: 59.23+/-7.34 years) and just menopaused women(mean age: 59.23+/-7.34), Periapical films were used from two groups of 20 randomly selected women. None of the subjects had a remarkabel medical history. To simplify protocal, we chose one interproximal bone area between the maxillary right canine and lateral inci sor for study. Each film was digitized into a 1312X1024 pixelX8 bit depth matrix by means of a Nikon 35 mm film scanner(LS-3510AF, Japan) with fixed gain and internal dark current correction to maintain constant illumination. The scanner was interfaced to a Macintosh LC III computer(Apple Computer, Charlotte, N.C.). Area and profile orientation were selecte d with a NIMH Image 1.37(NIH Research Services Brach, Bethesda, Md.). Histogram features were extracted form each profil e and area. The results of this study indicate that mean pixel intensities didn't differ significantly between two group s and there was a high correlation-coefficient between digitized radiographic profile features and area features.
Female
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Humans
;
Lighting
;
Maxilla
;
National Institute of Mental Health (U.S.)
5.Nonlinear contrast enhancement on subtraction images.
Journal of Korean Academy of Oral and Maxillofacial Radiology 1997;27(2):83-90
This study was performed to demonstrate the effect of linear or nonlinear contrast enhancement on subtraction images. Three different textures were radiograped on dental film. The first radiograph was taken without the presence of an object. the second, which showed trabucular bone, was taken of the molar area of a human. the third radiograph was taken of the coronal part of molars. Each film was digitized into a 1312 X 1024 pixel X 8 bit depth matrix by means of a Nikon 35 mm film scanner(LS-3510AF, Japan) with fixed gain and internal dark current correction to maintain constant illumination. The scanner was interfaced to a Macintosh LC III computer(Apple Computer, Charlotte, N.C.). This resulted in three pairs of images, including different textures-plain, bone and enamel. Digital regular, linearly and nonlinearly enhanced subtraction was performed. Computer software was used to simulate lesions in the shape of a 2D-Gaussian curve on each of a pair of images. The each subtraction images were presented in a random sequence to two groups of 10 observers(students and dentists). ROC analysis was used to compare observer performance. The following results were obtained; 1. All of LCE subtraction, equalized subtraction and regular subtraction images of plain texture were diagnosed the best by far. 2. The data revealed a siginificant LCE effect in both the student group and the expert group. 3. Clinical expertise was a helphul factor for the observers in this study.
Dental Enamel
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Humans
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Lighting
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Molar
;
ROC Curve
6.Characterization of trabecular bone structure using 2D Fourier transformation and fractal analysis.
Journal of Korean Academy of Oral and Maxillofacial Radiology 1998;28(2):339-353
The purpose of this study was to investigate whether a radiographic estimate of osseous fractal dimension and power spectrum of 2D discrete Fourier transform is useful in the characterization of structural changes in bone. Ten specimens of bone were decalcified in fresh 50 ml solutions of 0.1 N hydrochloric acid solution at cummulative timed periods of 0 and 90 minutes, and radiographed from 0 degree projection angle controlled by intraoral parelleling device. I performed one-dimensional variance, fractal analysis of bony profiles and 2D discrete Fourier transform. The results of this study indicate that variance and fractal dimension of scan line pixel intensities decreased significantly in decalcified groups but Fourier spectral analysis didn't discriminate well between control and decalcified specimens.
Fourier Analysis*
;
Fractals*
;
Hydrochloric Acid
;
Osteoporosis
7.Effect of Nimodipine on Ischemic Brain Edema of Gerbil.
Il Keon LEE ; Byung Woo YOON ; Jae Kyu RHO
Journal of the Korean Neurological Association 1991;9(4):413-417
The mechanisms involved in brain neuronal damage in ischemia are related to the elevation of cytosolic calcium concentration and calcium antagonist is considered as a promising drug that may alleviate ischemic neuronal damage. Using transient global ischemia model of Mongolian gerbil, we studied the effect of nimodipine, a cerebroselective calcium antagonist, on ischemic brain edema. We treated each gerbil intraperitoneally with nimodipine (lmg/kg) or the same amount of saline 30 minutes prior to ischemia, and transient global ischemia was induced by means of clipping both common carotid arteries either for 10 minutes or for 45 minutes. Three hours after reperfusion, the animals were decapitated and the water content of the bain was determined by oven dry method. With 10 minute ischemia the brain water content in nimodipine pretreatment group (78.6 +/- 0.2%) was lower than that in saline pretreatment group (79.1 +/- 0.4%) significantly (p<0.05). But with 45 minute ischemia nimodipine pretreatment did not reduce the postischemic increase of water content compared with saline pretreatment (79.8 +/- 0.4% and 79 6 +/- 0.4%, respectively; not significant). Our results suggest that nimodipine pretreatment may suppress the development of ischemic brain edema and its effect depends largely on the extent of brain ischemia.
Animals
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Brain Edema*
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Brain Ischemia
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Brain*
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Calcium
;
Carotid Artery, Common
;
Cytosol
;
Gerbillinae*
;
Ischemia
;
Neurons
;
Nimodipine*
;
Reperfusion
8.Secondary hemochromatosis in a long term hemodialysis patients.
Won Ho SHIN ; Dae Seok SHIM ; Kyung Lyul RYU ; Keon Yong KIM ; Keon Ho KIM ; Ok Jae LEE ; Il Yong HWANG
Korean Journal of Medicine 1993;45(5):676-680
No abstract available.
Hemochromatosis*
;
Humans
;
Renal Dialysis*
9.Effect of Group-Based Cognitive Training on Cognitive Performance, Depression, and Quality of Life in Community-Dwelling Elderly
Eyohan KO ; Eyohan KO ; Myeong-Il HAN ; Myeong-Il HAN ; Keon-Hak LEE ; Keon-Hak LEE ; Su-Jeong HONG ; Su-Jeong HONG
Journal of Korean Geriatric Psychiatry 2021;25(1):36-42
Objective:
There are reports that cognitive training improves cognitive performance in patients with mild cognitive impairment and dementia. However, the research on the effects of cognitive training in the community-dwelling elderly is insufficient. This study aimed to verify the effectiveness of cognitive training in the community-dwelling elderly.
Methods:
The participants were community-dwelling elderly aged 60 years or over. We collected demographic data and assessed Korean Version of Montreal Cognitive Assessment (MoCA-K), The Short form of the Geriatric Depression Scale-Korean (SGDS-K), and Geriatric Quality of Life-Dementia (GQOL-D). Cognitive training consisted of performing tasks for multi-cognitive domains. It was a paper- and group-based program, conducted 15 sessions each 60 minute. After the intervention, clinical characteristics were reassessed. Paired t-test, pearson correlation, analysis of covariance (ANCOVA) were performed using R version 3.6.1.
Results:
There were 206 participants. 162 participants completed the intervention, and were eligible for analyses. After the cognitive intervention, MoCA-K was improved 2.10±0.61 which was statistically significant (p<0.001). SGDS-K was decreased 0.57± 0.46 (p=0.003). GQOL-D was increased 1.65±1.64 (p=0.048). ANCOVA showed that the score change in MoCA-K was not in-fluenced by baseline SGDS-K or baseline GQOL-D score.
Conclusion
Group-and paper-based cognitive training could improve MoCA-K, SGDS-K, and GQOL-D for the communitydwelling elderly. Baseline SGDS-K and GQOL-D scores were not associated with cognitive training effects in the community-dwelling elderly.
10.Effect of Group-Based Cognitive Training on Cognitive Performance, Depression, and Quality of Life in Community-Dwelling Elderly
Eyohan KO ; Eyohan KO ; Myeong-Il HAN ; Myeong-Il HAN ; Keon-Hak LEE ; Keon-Hak LEE ; Su-Jeong HONG ; Su-Jeong HONG
Journal of Korean Geriatric Psychiatry 2021;25(1):36-42
Objective:
There are reports that cognitive training improves cognitive performance in patients with mild cognitive impairment and dementia. However, the research on the effects of cognitive training in the community-dwelling elderly is insufficient. This study aimed to verify the effectiveness of cognitive training in the community-dwelling elderly.
Methods:
The participants were community-dwelling elderly aged 60 years or over. We collected demographic data and assessed Korean Version of Montreal Cognitive Assessment (MoCA-K), The Short form of the Geriatric Depression Scale-Korean (SGDS-K), and Geriatric Quality of Life-Dementia (GQOL-D). Cognitive training consisted of performing tasks for multi-cognitive domains. It was a paper- and group-based program, conducted 15 sessions each 60 minute. After the intervention, clinical characteristics were reassessed. Paired t-test, pearson correlation, analysis of covariance (ANCOVA) were performed using R version 3.6.1.
Results:
There were 206 participants. 162 participants completed the intervention, and were eligible for analyses. After the cognitive intervention, MoCA-K was improved 2.10±0.61 which was statistically significant (p<0.001). SGDS-K was decreased 0.57± 0.46 (p=0.003). GQOL-D was increased 1.65±1.64 (p=0.048). ANCOVA showed that the score change in MoCA-K was not in-fluenced by baseline SGDS-K or baseline GQOL-D score.
Conclusion
Group-and paper-based cognitive training could improve MoCA-K, SGDS-K, and GQOL-D for the communitydwelling elderly. Baseline SGDS-K and GQOL-D scores were not associated with cognitive training effects in the community-dwelling elderly.