• Nuclear Medicine and Molecular Imaging
• /
• v.40 no.3
• /
• pp.186-187
• /
• 2006

A 64-year-old female with glioblastoma multiforme (GBM) was assigned to our department for whole body PET/CT scan. She ingested 1 liter of pure water as negative oral contrast just before PET/CT examination. FDG-PET/CT images showed a very intense hypermetabolic, focal lesion in the abdominal cavity around descending colon. The SUVmax of the lesion was 17.2. But there was no abnormal lesion corresponded to the area of PET scan in the combined contrast enhanced CT scan. We suggested considering a malignant lesion due to very intense glycolytic activity. Conventional abdominal CT scan & colonoscopy were accomplished within one week after PET/CT evaluation. There was no abnormality in both examinations. We executed follow-up PET/CT evaluation after 1 month and couldn't find any abnormality around the corresponding area. So we concluded the hypermetabolism was colonic physiologic uptake. A colonic physiologic uptake is a well known cause of false positive finding. Nuclear physicians should be considered the possibility of malignancy when interpret focal colonic uptake, especially incidental finding. There are a few reports that using of negative oral contrast is able to reduce gastrointestinal physiologic uptakes. But as we can see in this case, although we used negative oral contrast, intense physiologic uptake is detected and maxSUV is able to up to 17.2. So, it is important to keep a fact in mind. Even though there is a colonic physiologic uptake in PET/CT image, it may be able to show very intense hypermetabolism regardless of using negative oral contrast.

• Imaging Science in Dentistry
• /
• v.45 no.3
• /
• pp.141-145
• /
• 2015

Purpose: This study evaluated the diagnostic accuracy of the reverse contrast mode in intraoral digital radiography for the detection of proximal dentinal caries, in comparison with the original digital radiographs. Materials and Methods: Eighty extracted premolars with no clinically apparent caries were selected, and digital radiographs of them were taken separately in standard conditions. Four observers examined the original radiographs and the same radiographs in the reverse contrast mode with the goal of identifying proximal dentinal caries. Microscopic sections $5{\mu}m$ in thickness were prepared from the teeth in the mesiodistal direction. Four slides prepared from each sample used as the diagnostic gold standard. The data were analyzed using SPSS (${\alpha}=0.05$). Results: Our results showed that the original radiographs in order to identify proximal dentinal caries had the following values for sensitivity, specificity, positive predictive value, negative predictive value, and accuracy, respectively: 72.5%, 90%, 87.2%, 76.5%, and 80.9%. For the reverse contrast mode, however, the corresponding values were 63.1%, 89.4%, 87.1%, 73.5%, and 78.8%, respectively. The sensitivity of original digital radiograph for detecting proximal dentinal caries was significantly higher than that of reverse contrast mode (p<0.05). However, no statistically significant differences were found regarding specificity, positive predictive value, negative predictive value, or accuracy (p>0.05). Conclusion: The sensitivity of the original digital radiograph for detecting proximal dentinal caries was significantly higher than that of the reversed contrast images. However, no statistically significant differences were found between these techniques regarding specificity, positive predictive value, negative predictive value, or accuracy.

• Investigative Magnetic Resonance Imaging
• /
• v.5 no.1
• /
• pp.49-56
• /
• 2001

Purpose : To evaluate value of superparamagnetic iron oxide (SPIO) as a negative oral contrast agent in MR cholangiopancreatography (MRCP). Materials and methods : Forty-eight patients with suspected biliary tract or pancreatic diseases and six healthy volunteers were enrolled in this study. All MR images were obtained using a 1.5 T MR unit. MR-CP using fat-suppressed half-Fourier acquisition single-shot turbo spin echo (HASTE) and turbo spin echo (TSE) techniques were performed and reconstructed with maximal intensity projection (MIP). To determine the most optimal concentration of SPIO to obliterate the high signal intensity of water, a phantom experiment was conducted with various concentrations of SPIO-water mixture. Two radiologists evaluated pre- and postcontrast MRCPS. The contrast enhancement was assessed on the basis of loss of signal intensity in the stomach and duodenum. Results : In the phantom experiment, a significant increase of percentage of signal intensity loss (PSIL) occurred in concentration of 22.4 ugFe/ml (Feridex1 ml diluted with water 500 ml). Postcontrast MRCP showed an improved image quality compared with precontrast images. The rate of improvement in the diagnosis of diseases of the common bile duct and pancreatic duct was 25% (12/48). Conclusion : In patients with suspected biliary tract and pancreatic diseases, the SPIO is useful as a negative oral contrast agent for MRCP and provides an improvement of image quality.

• International Journal of Oral Biology
• /
• v.38 no.4
• /
• pp.149-154
• /
• 2013

In general, oleanolic acid (OA) and ursolic acid (UA) have antimicrobial effect against Gram-positive bacteria but not Gram-negative bacteria whereas sophoraflavanone G has antimicrobial activity against both bacterial types. However, the antimicrobial effects of OA, UA, and sophoraflavanone G against periodontopathogens have not been studied to any great extent. The aim of this study was to investigate antimicrobial effect of OA, UA, and sophoraflavanone G against 15 strains (5 species) of oral Gram-negative bacteria, which are the major causative bacteria of periodontal disease. The antimicrobial activity was evaluated by minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) determinations. OA and UA showed antimicrobial effects against all of the Porphyromonas gingivalis strains tested and also Prevotella intermedia ATCC $25611^T$. Interestingly, P. intermedia ATCC 49046 showed greater resistance to OA and UA than P. intermedia ATCC $25611^T$. In contrast, sophoraflavanone G had antimicrobial activity against all strains, with MIC and MBC values below $32{\mu}g/ml$, except Aggregatibacter actinomycetemcomitans. These results indicate that sophoraflavanone G may have potential for use in future oral hygiene products such as dentifrices and gargling solution to prevent periodontitis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.38 no.1
• /
• pp.38-43
• /
• 2012

Introduction: The location of parotid gland tumors in the superficial or deep lobes can affect the time and difficulty of operations. Therefore, accurate preoperative evaluation of the tumor location is important for surgical outcomes. Materials and Methods: A total of 16 patients with parotid gland tumors and who underwent a parotidectomy between April 2003 and March 2011 were retrospectively reviewed in terms of demographic background, tumor location, surgical treatment, and treatment outcomes. Tumor location was estimated by four landmarks on contrast enhanced computerized tomography scans, which were Conn's arc, the facial nerve (FN) line, the Utrecht line, and the retromandibular vein. Tumor location was confirmed by relative position depending on the facial nerve during surgery. It was assumed positive since the tumor lies in the superficial lobe of the parotid gland, the sensitivity, specificity, positive predictive value, negative predictive value, and efficiency of each landmark were evaluated. Results: Our result revealed that the facial nerve line had a sensitivity of 83.3%, specificity of 100%, positive predictive value of 100%, negative predictive value of 71.4%, and efficiency of 87.5%. Some would be more efficient preoperative evaluation methods of the relationship of parotid gland tumors to the facial nerve than others. Conclusion: In our study, the FN line was found to be the most reliable analysis method.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.16
• /
• pp.6787-6790
• /
• 2014

Background: The aim of this study was to evaluate cyclooxygenase-2 (COX-2) immunoreactivity in colorectal adenocarcinomas and to find correlations with different pathological features. Materials and Methods: This study included 35 cases of colorectal carcinoma foir which surgical colectomy specimens were collected. Immunohistochemical staining of COX-2 (cyclooxygenase-2) is done by using the Streptavidin-biotin technique. Results: This work reveals that COX-2 is positive in most cases of colorectal carcinoma and negative in normal colon tissue with statistically non significant relations between COX-2 immunostaining and different pathological features. Conclusions: Our data suggest over expression of COX-2 protein in colorectal carcinoma in contrast to normal mucosa, with a possible role in cell proliferation in carcinogenesis.

• Korean Journal of Head & Neck Oncology
• /
• v.21 no.2
• /
• pp.196-200
• /
• 2005

Objectives: The purpose of this study was to evaluate the incidence and predictive factors of contralateral occult lymph node metastasis in oral cavity squamous cell carcinomas to form a rational basis for elective contralateral neck management. Materials and Methods: We performed a retrospective analysis of 66 N0-2 oral cavity cancer patients undergoing elective neck dissection for contralateral clinically negative necks from 1991 to 2003. Results: Clinically negative but pathologically positive contralateral lymph nodes occurred in 11%(7 of 66) . Of the 11 cases with a clinically ipsilateral node positive neck, contralateral occult lymph node metastases developed in 36%(4 of 10, in contrast with 5%(3/55) in the cases with clinically ipsilateral node negative necks(p<0.05). Based on the clinical staging of the tumor, 8%(3 of 37) of the cases showed lymph node metastases in T2 tumors, 25%(2 of 8) in T3, and 18%(2 of 11) in T4. None of the T1 tumors(10 cases) had pathologically positive lymph nodes. The rate of contralateral occult neck metastasis was significantly higher in advanced stage cases and those crossing the midline, compared to early stage or unilateral lesions(p<0.05). Patients with no evidence of contralateral nodal cancer had significantly improved disease-specific survival over patients with any pathologically positive nodes(5-year disease-specific survival rate was 79% vs. 43%, p<0.05). Conclusion: The risk of contralateral occult neck involvement in the oral cavity squamous cell carcinomas above the T3 stage or those crossing the midline with unilateral metastases was high. Therefore, we advocate an elective contralateral neck treatment with surgery or radiotherapy in oral cavity squamous cell carcinoma patients with ipsilateral node metastases or tumors that are greater than stage T3 or crossing the midline.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.42 no.3
• /
• pp.133-138
• /
• 2016

Objectives: To assess the association between muscle invasion by oral squamous cell carcinoma of the posterior mandibular alveolar ridge and cervical lymph node metastasis on the basis of preoperative magnetic resonance imaging (MRI). Materials and Methods: Twenty-six patients with oral squamous cell carcinoma of the posterior mandibular alveolar ridge were evaluated by MRI. The associations between cervical lymph node metastasis and independent factors evaluated by MRI were analyzed. Overall survival was also analyzed in this manner. Representative biopsy specimens were stained with anti-podoplanin and anti-CD34 antibodies. Results: Mylohyoid muscle invasion was associated with cervical lymph node metastasis. A combinational factor of mylohyoid and/or buccinator muscle invasion was also associated with cervical lymph node metastasis. Cervical lymph node metastasis and masticator space invasion had a negative effect on overall survival. No lymphatic vessels were identified near the tumor invasion front within the mandible. In contrast, lymphatic vessels were identified near the front of tumor invasion in the muscles. Conclusion: This study demonstrates an association between muscular invasion by oral squamous cell carcinoma of the posterior mandibular alveolar ridge and cervical lymph node metastasis.

• International Journal of Oral Biology
• /
• v.36 no.3
• /
• pp.109-116
• /
• 2011

Periodontitis results from the activation of host immune and inflammatory defense responses to subgingival plaque bacteria, most of which are gram-negative rods with lipopoly-saccharides (LPSs) in their cell walls. LPSs have been known to induce proinflammatory responses and recently it was reported also that they induce the expression of microRNAs (miRNAs) in host cells. In our current study therefore, we aimed to examine and compare the miRNA expression patterns induced by the LPSs of major periodontopathogens in the human gingival epithelial cell line, Ca9-22. The cells were treated with 1 ${\mu}g$/ml of E. coli (Ec) LPS or 5 ${\mu}g$/ml of an LPS preparations from four periodontopathogens Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Aggregatibacter actinomycetemcomitans (Aa), and Fusobacterium nucleatum (Fn) for 24 h. After small RNA extraction from the treated cells, miRNA microarray analysis was carried out and characteristic expression profiles were observed. Fn LPS most actively induced miRNAs related to inflammation, followed by Aa LPS, Pi LPS, and Ec LPS. In contrast, Pg LPS only weakly activated miRNAs related to inflammation. Among the miRNAs induced by each LPS, miR-875-3p, miR-449b, and miR-520d-3p were found to be commonly up-regulated by all five LPS preparations, although at different levels. When we further compared the miRNA expression patterns induced by each LPS, Ec LPS and Pi LPS were the most similar although Fn LPS and Aa LPS also induced a similar miRNA expression pattern. In contrast, the miRNA profile induced by Pg LPS was quite distinctive compared with the other bacteria. In conclusion, miR-875-3p, miR-449b, and miR-520d-3p miRNAs are potential targets for the diagnosis and treatment of periodontal inflammation induced by subgingival plaque biofilms. Furthermore, the observations in our current study provide new insights into the inflammatory miRNA response to periodontitis.

• Journal of Korean society of Dental Hygiene
• /
• v.9 no.2
• /
• pp.13-24
• /
• 2009

The purpose of this study was to examine the relationship between the dietary habits and oral health of elderly people in an attempt to pave the way for the development of oral health promotion programs geared toward improving the quality of life of the elderly. The subjects in this study were senior citizens who were selected by convenience sampling from Seoul. The findings of the study were as follows: 1. Regarding subjective oral health state, 54.5% of the elderly people, more than the half, considered their mouth to be in good health. The number of their mean remaining permanent teeth was 13.71. 47.5 percent of the senior citizens investigated had no shaking teeth. 2. Those who found themselves to be in good oral health had meals on a regular basis(p=0.022) and ate detergent food often. The gaps between them and the others was significant(p=0.005). In contrast, the elderly people who were in a bad oral health frequently ate cariogenic food(p=0.044). 3. The elderly people who had 21 teeth or more ate detergent food often(p=0.029), and those who owned no teeth had a sweet teeth(p=0.003), ate more cariogenic food(p=0.001) and had a snack frequently(p=0.026). 4. The subjective oral health status had a positive correlation to detergent food intake(r=0.23) and had a slightly negative correlation to preference for sweets(r=-0.14), cariogenic food intake(r=-0.14) and snack intake(r=-0.06). The number of tooth was positively correlated to detergent food intake(r=0.23) and negatively to preference for sweets(r=0.32), cariogenic food intake(r=-0.30) and snack intake(r=-0.21). The presence or absence of shaking teeth had a positive correlation to snack intake(r=0.14). The above-mentioned findings suggested that the dietary habits of the elderly people had a statistically significant relationship to subjective and objective oral health state, which indicated that there was a close relationship between oral health and dietary habits. Therefore how to improve dietary habits as well as oral health should be taken into account when oral health promotion programs are developed for the sake of the elderly. That would contribute to promoting the oral health of elderly people and eventually boosting their quality of life.