• Applied Microscopy
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• v.10 no.1_2
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• pp.27-32
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• 1980

A case of cutaneous leishmaniasis developed in a 48 year old Korean male who returned from middle east was studied by light and electron microscopic observations. Light microscopically, the lesion consisted of heavy chronic ill-defined granulomatous inflammation involving entire thickness of the dermis, composed of mainly histiocytic and small mononuclear cell infiltrations without evidence of necrosis or giant cell formation. Giemsa staining revealed numerous intracellular micro-organisms within histiocytes, showing dark stained central dot surrounded by light stained cytoplasm. Electron microscopically, the organisms were observed mostly ovoid in shape and frequently binary mitotic features within the host cells. follicle consisted of double unit membranes and microtubules, which are immediately below these membrnae. A long kinetoplast was noted within a very elongated mitochondrion at the center of the organisms and a flagella rose in front of the kineoplast but ended within the cytoplasm. Large numbers of free ribosomes, occasional Golgi complex and SER were also noted, but RER was seldom found. These ultrastructural features corresponded to promastigote stage of Leishmania tropica. In principle, leishmaniasis is a tropical disease and can not be found in temperate zone. However, travel to mideast by many Koreans may contract this disease while they are in endemic regions.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1267-1272
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• 2012

Background and Objective: The optimal resection extent for clinically unilateral papillary thyroid microcarcinoma (PTMC) remains controversial. The objective was to investigate risk factors associated with occult contralateral carcinoma, and put emphasis on the predictive value of preoperative BRAF mutation. Materials and Methods: 100 clinically unilateral PTMC patients all newly diagnosed, previously untreated were analyzed in a prospective cohort study. We assessed the T1799A BRAF mutation status in FNAB specimens obtained from all PTMC patients before undergoing total thyroidectomy (TT) and central lymph node dissection (CLND) for PTMC. Univariate and multivariate analyses were used to reveal the incidence of contralateral occult cancer, difference of risk factors and predictive value, with respect to the following variables: preoperative BRAF mutation status, age, gender, tumor size, multifocality of primary tumor, capsular invasion, presence of Hashimoto thyroiditis and central lymph node metastasis. Results: 20 of 100 patients (20%) had occult contralateral lobe carcinoma. On multi-variate analysis, preoperative BRAF mutation (p = 0.030, OR = 3.439) and multifocality of the primary tumor (p = 0.004, OR = 9.570) were independent predictive factors for occult contralateral PTMC presence. However, there were no significant differences between the presence of occult contralateral carcinomas and age, gender, tumor size, capsular invasion, Hashimoto thyroiditis and central lymph node metastasis. Conclusions: Total thyroidectomy, including the contralateral lobe, should be considered for the treatment of unilateral PTMC if preoperative BRAF mutation is positive and/or if the observed lesion presents as a multifocal tumor in the unilateral lobe.

• Investigative Magnetic Resonance Imaging
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• v.17 no.1
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• pp.59-62
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• 2013

There are various types of foreign body reactions, such as inflammation, edema, fluid collection, hematoma, infection, abscess and granulomas. There are various imaging findings according to types of foreign bodies and depending on the lapse of time. Therefore, correct diagnosis of a foreign body reaction is difficult and easily confused with soft tissue neoplasm. The MRI is ideal for the detection of foreign bodies regardless of radiolucency or acoustic impedance. It is especially very useful in the evaluation of the surrounding tissue reaction. The authors report a case of a 26-year-old female patient with both forearm swelling due to self-injection of a mixture of powdered tablets and saline. The lesion shows numerous internal T1 and T2 dark signal intensity micro-spots with surrounding fluid collection, which are diagnosed as foreign bodies with surrounding inflammatory changes during an operation.

• Journal of Korean Neurosurgical Society
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• v.30 no.10
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• pp.1187-1192
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• 2001

Objective : The lateral extracavitary approach(LECA) to the thoracolumbar spine is known as one of procedure which allows not only direct vision of pathologic lesion, but also ventral decompression, and dorsal fixation of the spine through the same incision. However, some drawbacks of LECA, including the technically- demanding, time-consuming, unfamiliar surgical anatomy and excessive blood loss, make surgeons to hesitate to use this approach. This study is to provide the surgical anatomy of LECA using cadavers, for detailed informations when LECA is considered for the surgery. Methods : We performed the 10 cadaveric studies, 7 male and 3 female, and careful dissection was carried out on right side of thoracolumbar region, except one for thoracic region. The photographs with micro-lens were taken to depict the close-up findings and for demonstrating detailed anatomy. Results : The photographs and hand-drawings demonstrated the relationships among the musculature, segmental vessels and nerve roots seen during each dissection plane. The lateral branches of dorsal rami of spinal nerve and the transverse process were confirmed to be the most important landmark of this approach. Conclusion : We concluded that detailed anatomical findings for LECA through this step-by-step dissection would be useful during operative intervention to reduce the intraoperative complications in LECA.

• International Journal of Oral Biology
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• v.45 no.1
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• pp.1-7
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• 2020

Oral lichen planus (OLP) is a chronic inflammatory disease observed in approximately 0.5-2.2% of the population, and it is recognized as a premalignant lesion that can progress into oral squamous cell carcinoma (OSCC). The rate of malignant transformation is approximately 1.09-2.3%, and the risk factors for malignant transformation are age, female, erosive type, and tongue site location. Malignant transformation of OLP is likely related to the low frequency of apoptotic phenomena. Therefore, apoptosis-related genetic factors, like p53, BCL-2, and BAX are reviewed. Increased p53 expression and altered expression of BCL-2 and BAX were observed in OLP patients, and the malignant transformation rate in these patients was relatively higher. The involvement of microRNA (miRNA) in the malignant transformation of OLP is also reviewed. Because autophagy is involved in cell survival and death through the regulation of various cellular processes, autophagy-related genetic factors may function as factors for malignant transformation. In OLP, decreased levels of ATG9B mRNA and a higher expression of IGF1 were observed, suggesting a reduction in cell death and autophagic response. Activated IGF1-PI3K/AKT/mTor cascade may play an important role in a signaling pathway related to the malignant transformation of OLP to OSCC. Recent research has shown that miRNAs, such as miR-199 and miR-122, activate the cascade, increasing the prosurvival and proproliferative signals.

• Journal of the korean academy of Pediatric Dentistry
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• v.37 no.3
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• pp.288-297
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• 2010

The purpose of this study was to evaluate the effect of light cured fluoride-releasing materials on the inhibition of demineralization. In addition, the pattern of fluoride uptake of adjacent tooth structure was analyzed with EPMA. Eighty intact premolars were restored with $Filtek^{TM}$ Z250(control group, composite), Fuji Filling $LC^{TM}$(RMGI), Dyract $AP^{(R)}$ (compomer) and Beautifil II(giomer). Restored teeth were stored in distilled water for 30 days. Then sixty teeth(n=15) were exposed to demineralizing solution(pH 4.3). Demineralized teeth were bisected and polished. The specimens were observed with confocal laser scanning microscope. The depth of outer lesion and the thickness of inhibition zone were measured. Remained twenty teeth(n=5) were bisected for fluoride uptake analysis. The fluoride analysis were taken at enamel-restoration interface and dentin-restoration interface by electron probe micro-analyzer. The results are as follows: 1. The depth of outer lesion of Fuji Filling $LC^{TM}$ Dyract AP, Beautifil II was shallower than that of $Filtek^{TM}$ Z250 at the margin of restoration(p<0.05). 2. The thickness of caries inhibition zone of Fuji Filling $LC^{TM}$, Dyract AP, Beautifil II was greater than that of $Filtek^{TM}$ Z250 at the margin of restoration(p<0.05). 3. Fuji Filling $LC^{TM}$, Dyract AP, Beautifil II groups showed the greater fluoride uptake into enamel and dentine around restoration than $Filtek^{TM}$ Z250 group. 4. In dentin the difference of fluoride concentration were greater than in enamel, and Dyract AP showed the greatest fluoride concentration in dentin.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.25-41
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• 1986

The applicability of micro-ELISA was evaluated in human neuro-cysticercosis using paired samples of serum and CSF. A total of 355 cases who were mostly neurologic patients was subjected. Cystic fluid of C. cellulosae was used as antigen in protein concentration of $2.5{\;}{\mu}g/ml$. Serum was diluted to 1 : 100 and CSF was undiluted in the assay for the specific IgG antibody level. The differential criterion of the positive reaction was the abs. of o. 18 in both samples. The results were summarized as follows: 1. The overall sensitivity of the micro-ELISA in 71 confirmed neurocysticercosis was 90.1% ; the sensitivity by serum was 77.5% and that by CSF was 83.1%. CSF was a more sensitive and valuable material. Most of the false negative cases of neuro-cysticercosis showed far lower level of abs. rather than marginal. 2. The overall specificity of the micro-ELISA in 52 confirmed other neurologic diseases was 88.5%; the specificities by serum and by CSF were 94.2% respectively. Cases of other neurologic diseases did not show false positive reactions in both samples. 3. When serum was assayed, taeniasis(2/18), sparganosis(2/20), paragonimiasis(1/56), clonorchiasis(1/15) and fascioliasis(1/1) cases showed cross reactions. When CSF was assayed, 2 ot 10 neuro-sparganosis showed cross reactions while none of 9 neuro-paragonimiasis showed it. Out of 71 confirmed neuro-cysticercosis cases, 6 and 11 showed cross reactions by serum and CSF to crude extract antigen of sparganum; but no case did show it to crude extract antigen of Paragonimus westermani. 4. Ventricular CSF showed low or negative levels of IgG antibody than lumbar CSF unless the lesion was at the lateral ventricle itself. 5. Out of 4 racemose cysticercosis cases, 3 showed positive reaction in serum while all of 3 examined CSF were positive. The above results indicated that the serological test for detecting the specific IgG antibody by micro-ELISA using paired samples of serum and CSF was very helpful for clinical differentiation of neuro-cysticercosis from neurologic diseases of other causes.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.150-156
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• 2000

Purpose : Stereotactic radiation therapy (SRT) can deliver highly focused radiation to a small and spherical target lesion with very high degree of mechanical accuracy. For non-spherical and large lesions, however, inclusion of the neighboring normal structures within the high dose radiation volume is inevitable in SRT This is to report the beam shaping using the partial closure of the independent jaw in SRT and the verification of dose calculation and the dose display using a home-made soft ware. Materials and Methods : Authors adopted the idea to partially close one or more independent collimator jaw(5) in addition to the circular collimator cones to shield the neighboring normal structures while keeping the target lesion within the radiation beam field at all angles along the arc trajectory. The output factors (OF's) and the tissue-maximum ratios (TMR's) were measured using the micro ion chamber in the water phantom dosimetry system, and were compared with the theoretical calculations. A film dosimetry procedure was peformed to obtain the depth dose profiles at 5 cm, and they were also compared with the theoretical calculations, where the radiation dose would depend on the actual area of irradiation. Authors incorporated this algorithm into the home-made SRT software for the isodose calculation and display, and was tried on an example case with single brain metastasis. The dose-volume histograms (DVH's) of the planning target volume (PTV) and the normal brain derived by the control plan were reciprocally compared with those derived by the plan using the same arc arrangement plus the independent collimator jaw closure. Results : When using 5.0 cm diameter collimator, the measurements of the OF's and the TMR's with one independent jaw set at 30 mm (unblocked), 15.5 mm, 8.6 mm, and 0 mm from th central beam axis showed good correlation to the theoretical calculation within 0.5% and 0.3% error range. The dose profiles at 5 cm depth obtained by the film dosimetry also showed very good correlation to the theoretical calculations. The isodose profiles obtained on the home-made software demonstrated a slightly more conformal dose distribution around the target lesion by using the independent jaw closure, where the DVH's of the PTV were almost equivalent on the two plans, while the DVH's for the normal brain showed that less volume of the normal brain receiving high radiation dose by using this modification than the control plan employing the circular collimator cone only. Conclusions : With the beam shaping modification using the independent jaw closure, authors have realized wider clinical application of SRT with more conformal dose planning. Authors believe that SRT, with beam shaping ideas and efforts, should no longer be limited to the small spherical lesions, but be more widely applied to rather irregularly shaped tumors in the intracranial and the head and neck regions.

• Restorative Dentistry and Endodontics
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• v.32 no.1
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• pp.69-79
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• 2007

The purpose of this study was to investigate the effects of composite resin restorations on the stress distribution of notch shaped noncarious cervical lesion using three-dimensional (3D) finite element analysis (FEA). Extracted maxillary second premolar was scanned serially with Micro-CT (SkyScan1072 ; SkyScan, Aartselaar, Belgium). The 3D images were processed by 3D-DOCTOR (Able Software Co., Lexington, MA, USA). ANSYS (Swanson Analysis Systems, Inc., Houston, USA) was used to mesh and analyze 3D FE model. Notch shaped cavity was filled with hybrid or flowable resin and each restoration was simulated with adhesive layer thickness ($40{\mu}m$) A static load of 500 N was applied on a point load condition at buccal cusp (loading A) and palatal cusp (loading B). The principal stresses in the lesion apex (internal line angle of cavity) and middle vertical wall were analyzed using ANSYS. The results were as follows 1. Under loading A, compressive stress is created in the unrestored and restored cavity. Under loading B, tensile stress is created. And the peak stress concentration is seen at near mesial corner of the cavity under each load condition. 2. Compared to the unrestored cavity, the principal stresses at the cemeto-enamel junction (CEJ) and internal line angle of the cavity were more reduced in the restored cavity on both load con ditions. 3. In teeth restored with hybrid composite, the principal stresses at the CEJ and internal line angle of the cavity were more reduced than flowable resin.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.1
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• pp.61-69
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• 2008

Purpose: Micro-pinhole SPECT system with conventional multiple-head gamma cameras has the advantage of high magnification factor for imaging of rodents. However, several geometric factors should be calibrated to obtain the SPECT image with good image quality. We developed a simplified geometric calibration method for rotating triple-head pinhole SPECT system and assessed the effects of the calibration using several phantom and rodent imaging studies. Materials and Methods: Trionix Triad XLT9 triple-head SPECT scanner with 1.0 mm pinhole apertures were used for the experiments. Approximately centered point source was scanned to track the angle-dependent positioning errors. The centroid of point source was determined by the center of mass calculation. Axially departed two point sources were scanned to calibrate radius of rotation from pinhole to center of rotation. To verify the improvements by the geometric calibration, we compared the spatial resolution of the reconstructed image of Tc-99m point source with and without the calibration. SPECT image of micro performance phantom with hot rod inserts was acquired and several animal imaging studies were performed. Results: Exact sphere shape of the point source was obtained by applying the calibration and axial resolution was improved. Lesion detectibility and image quality was also much improved by the calibration in the phantom and animal studies. Conclusion: Serious degradation of micro-pinhole SPECT images due to the geometric errors could be corrected using a simplified calibration method using only one or two point sources.