• Journal of Environmental Health Sciences
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• v.40 no.2
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• pp.105-113
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• 2014

Objectives: It is necessary to apply quantitative structure activity relationship (QSAR) for the various chemicals with insufficient toxicity data that are used in the workplace, based on the precautionary principle. This study aims to find application plan of QSAR software tool for predicting health hazards such as genetic toxicity, and carcinogenicity for some chemicals used in the electronics industries. Methods: Toxicity prediction of 21 chemicals such as 5-aminotetrazole, ethyl lactate, digallium trioxide, etc. used in electronics industries was assessed by Toxicity Prediction by Komputer Assisted Technology (TOPKAT). In order to identify the suitability and reliability of carcinogenicity prediction, 25 chemicals such as 4-aminobiphenyl, ethylene oxide, etc. which are classified as Group 1 carcinogens by the International Agency for Research on Cancer (IARC) were selected. Results: Among 21 chemicals, we obtained prediction results for 5 carcinogens, 8 non-carcinogens and 8 unpredictability chemicals. On the other hand, the carcinogenic potential of 5 carcinogens was found to be low by relevant research testing data and Oncologic TM tool. Seven of the 25 carcinogens (IARC Group 1) were wrongly predicted as non-carcinogens (false negative rate: 36.8%). We confirmed that the prediction error could be improved by combining genetic toxicity information such as mutagenicity. Conclusions: Some compounds, including inorganic chemicals and polymers, were still limited for applying toxicity prediction program. Carcinogenicity prediction may be further improved by conducting cross-validation of various toxicity prediction programs, or application of the theoretical molecular descriptors.

• The Journal of Korean Society of Virology
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• v.30 no.2
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• pp.151-159
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• 2000

Hepatitis C virus (HCV) is one of the important human pathogen that can cause acute and chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Recently, the third generation radiation immuno assay (RIA) method has been developed as a very sensitive test to detect anti-HCV antibody. However, false positive is the problem with RIA test. To solve this the RIA results were compared to those of 5-antigen recombinant immunoblot assay (5-RIBA) and reverse transcription-polymerase chain reaction (RT-PCR). Among 12,767 serum samples tested from clinic visitors, total 275 (2.2%) samples were antibody positive by RIA. RIBA was performed with 148 RIA positives cases but among them was shown eighty five was antibody positive and sixty three (42.6%) was negative result. However, nested RT-PCR test was shown also carried out with 43 positive, 6 intermediates and 25 negatives of RIBA. As a result of the nested RT-PCR results, HCV antigen were detected in RIBA positive, 33.3% (2/6) RIBA intermediate and 12% (3/25). Clinical syndrome of all 148 patients as a with chronic active hepatitis (46.0%), cirrhosis (18.9%), hepatocellular carcinoma (8.1%) and others (27.0%) and they were positive in reaction by RIA test. But RIBA positive patients with 34.9% of chronic active hepatitis, 18.6% of cirrhosis, 4.6% of hepatocellular carcinoma and 41.9% of others were detected to be positive case by nested RT-PCR.

• Imaging Science in Dentistry
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• v.50 no.3
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• pp.209-216
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• 2020

Purpose: In India, the age of 14 years is the legal age threshold for child labour. Therefore, in suspected instances of child labour, age assessment plays a crucial role in determining whether a violation of the law on the employment of children has occurred. The aim of this retrospective cross-sectional study was to assess the discriminatory ability of stages of cervical vertebral maturation (CVM) in predicting the legal age threshold of 14 years. Materials and Methods: Routinely taken lateral cephalograms from 408 subjects aged 10 to 18 years were evaluated retrospectively using the CVM stages described by Baccetti et al. Descriptive statistics, accuracy, sensitivity, specificity, positive and negative predictive values, and likelihood ratios were calculated for stages 2, 3, and 4 of CVM. Results: Real age increased as the CVM stage gradually increased. The results of 2×2 contingency tables showed that CVM stage 4 produced an accuracy of 71% and 73%, a false positive rate of 7% and 18%, and a post-test probability of 59% and 68% for boys and girls, respectively. Conclusion: Based on these findings, it can be concluded that the stages of CVM are of limited use for predicting the attainment of the legal age threshold of 14 years. Future studies should investigate whether combinations of skeletal and dental methods could achieve better accuracy and post-test probability.

• Journal of Gastric Cancer
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• v.16 no.1
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• pp.14-20
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• 2016

Purpose: Early diagnosis of gastric cancer is still the exception in Western countries. In the East, as in Japan and Korea, this disease is an endemic disorder. More conservative surgical procedures are frequently performed in early gastric cancer cases in these countries where sentinel lymph node navigation surgery is becoming a safe option for some patients. This study aims to evaluate preliminary outcomes of patients with early gastric cancer who underwent sentinel node navigation surgeries in Brazil, a country with non-endemic gastric cancer levels. Materials and Methods: From September 2008 to March 2014, 14 out of 205 gastric cancer patients underwent sentinel lymph node navigation surgeries, which were performed using intraoperative, endoscopic, and peritumoral injection of patent blue dye. Results: Antrectomies with Billroth I gastroduodenostomies were performed in seven patients with distal tumors. The other seven patients underwent wedge resections. Sentinel basin resections were performed in four patients, and lymphadenectomies were extended to stations 7, 8, and 9 in the other 10. Two patients received false-negative results from sentinel node biopsies, and one of those patients had micrometastasis. There was one postoperative death from liver failure in a cirrhotic patient. Another cirrhotic patient died after two years without recurrence of gastric cancer, also from liver failure. All other patients were followed-up for 13 to 79 months with no evidence of recurrence. Conclusions: Sentinel lymph node navigation surgery appears to be a safe procedure in a country with non-endemic levels of gastric cancer.

• The Korean Journal of Cytopathology
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• v.18 no.2
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• pp.126-132
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• 2007

The aim of this study was to evaluate the diagnostic value of fine needle aspiration cytology (FNAC) for the assessment of palpable enlarged lymph nodes. The authors reviewed the results of 1,346 FNACs of palpable enlarged lymph nodes performed at Pusan National University Hospital from 1998 to 2004. Of the 1,346 cases, 1,265 (94.0%) were satisfactory and 81 (6.0%) unsatisfactory. Cytologic diagnoses were judged in 488 cases, based on subsequent histologic diagnoses, clinical follow up, or both. Global results for all malignancies (lymphoid and non-lymphoid neoplasms) based on cases with final diagnoses, showed a sensitivity of 87.4% and a specificity of 98.7%. The overall diagnostic accuracy was 93,2%, and the false negative rate reduced from 12,6% to 7,3% when lymphomatous cases were excluded. The annual data for this period showed that the number of diagnostic lymph node biopsies and the rate of inadequately sampled material markedly decreased. Gene rearrangement studies for IgH and TCR ${\gamma}$ were helful in 30 cases. FNAC is a useful initial diagnostic procedure for the evaluation of palpable enlarged lymph nodes. However, the technique should be assisted by the appropriate ancillary studies and by proper interpretation by a cytopathologist.

• The KIPS Transactions:PartC
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• v.15C no.5
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• pp.351-358
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• 2008

Recently, as network flooding attacks such as DoS/DDoS and Internet Worm have posed devastating threats to network services, rapid detection and proper response mechanisms are the major concern for secure and reliable network services. However, most of the current Intrusion Detection Systems(IDSs) focus on detail analysis of packet data, which results in late detection and a high system burden to cope with high-speed network environment. In this paper we propose a lightweight and fast detection mechanism for traffic flooding attacks. Firstly, we use SNMP MIB statistical data gathered from SNMP agents, instead of raw packet data from network links. Secondly, we use a machine learning approach based on a Support Vector Machine(SVM) for attack classification. Using MIB and SVM, we achieved fast detection with high accuracy, the minimization of the system burden, and extendibility for system deployment. The proposed mechanism is constructed in a hierarchical structure, which first distinguishes attack traffic from normal traffic and then determines the type of attacks in detail. Using MIB data sets collected from real experiments involving a DDoS attack, we validate the possibility of our approaches. It is shown that network attacks are detected with high efficiency, and classified with low false alarms.

• Clinical and Experimental Pediatrics
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• v.57 no.6
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• pp.278-286
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• 2014

Purpose: To evaluate the potential utility of $^{123}I$-metaiodobenzylguanine ($^{123}I$-MIBG) scintigraphy and $^{18}F$-fluorodeoxyglucose ($^{18}F$-FDG) positron emission tomography (PET) for the detection of primary and metastatic lesions in pediatric neuroblastoma (NBL) patients, and to determine whether $^{18}F$-FDG PET is as beneficial as $^{123}I$-MIBG imaging. Methods: We selected 8 NBL patients with significant residual mass after operation and who had paired $^{123}I$-MIBG and $^{18}F$-FDG PET images that were obtained during the follow-up. We retrospectively reviewed the clinical charts and the findings of 45 paired scans. Results: Both scans correlated relatively well with the disease status as determined by standard imaging modalities during follow-up; the overall concordance rates were 32/45 (71.1%) for primary tumor sites and 33/45 (73.3%) for bone-bone marrow (BM) metastatic sites. In detecting primary tumor sites, $^{123}I$-MIBG might be superior to $^{18}F$-FDG PET. The sensitivity of $^{123}I$-MIBG and $^{18}F$-FDG PET were 96.7% and 70.9%, respectively, and their specificity were 85.7% and 92.8%, respectively. $^{18}F$-FDG PET failed to detect 9 true NBL lesions in 45 follow-up scans (false negative rate, 29%) with positive $^{123}I$-MIBG. For bone-BM metastatic sites, the sensitivity of $^{123}I$-MIBG and $^{18}F$-FDG PET were 72.7% and 81.8%, respectively, and the specificity were 79.1% and 100%, respectively. $^{123}I$-MIBG scan showed higher false positivity (20.8%) than $^{18}F$-FDG PET (0%). Conclusion: $^{123}I$-MIBG is superior for delineating primary tumor sites, and $^{18}F$-FDG PET could aid in discriminating inconclusive findings on bony metastatic NBL. Both scans can be complementarily used to clearly determine discrepancies or inconclusive findings on primary or bone-BM metastatic NBL during follow-up.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.3
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• pp.187-192
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• 2015

Purpose: Measurement of serum ceruloplasmin level is the first step in screening for Wilson's disease (WD). Despite the rarity of WD in the general population, ceruloplasmin levels are routinely measured through hepatitis screening in both adults and children. Herein, we evaluated the diagnostic value of ceruloplasmin for the diagnosis of WD among children with hepatitis. Methods: We retrospectively reviewed data on serum ceruloplasmin levels measured as a serologic marker for patients with hepatitis at Asan Medical Center (Seoul, Korea) between from January 2004 to November 2013. The diagnosis of WD was confirmed by the identification of pathogenic variants in the ATP7B gene. To determine the diagnostic accuracy of ceruloplasmin, receiver operation characteristic (ROC) curves were constructed and the area under curve (AUC) were calculated. Results: Measurements of serum ceruloplasmin were performed in 2,834 children who had hepatitis. Among these, 181 (6.4%) children were diagnosed with WD. The sensitivity, specificity, and accuracy of a ceruloplasmin level of <20 mg/dL in the discrimination of WD were 93.4%, 84.2%, and 84.8%, respectively. In this study, 418 (14.7%) false-positive cases and 12 (0.4%) false-negative cases were noted. Using a ROC curve, a ceruloplasmin level of ${\leq}16.6mg/dL$ showed the highest AUC value (0.956) with a sensitivity of 91.2%, a specificity of 94.9%, and an accuracy of 94.7%. Conclusion: The measurement of serum ceruloplasmin was frequently used for the screening of WD in children, despite a low positive rate. The diagnostic value of ceruloplasmin may be strengthened by adopting a new lower cut-off level.

• Journal of Preventive Medicine and Public Health
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• v.52 no.2
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• pp.131-139
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• 2019

Objectives: Self-reporting can be used to determine the incidence and prevalence of hypertension (HTN). The present study was conducted to determine the validity of self-reported HTN and to identify factors affecting discordance between self-reported and objectively measured HTN in participants in the Ravansar Non-Communicable Diseases (RaNCD) cohort. Methods: The RaNCD cohort included permanent residents of Ravansar, Iran aged 35-65 years. Self-reported data were collected before clinical examinations were conducted by well-trained staff members. The gold standard for HTN was anti-hypertensive medication use and blood pressure measurements. The sensitivity, specificity, positive and negative predictive values, and overall accuracy of self-reporting were calculated. Univariate and multivariate logistic regression were used to examine the discordance between self-reported HTN and the gold standard. Results: Of the 10 065 participants in the RaNCD, 4755 (47.4%) were male. The prevalence of HTN was 16.8% based on self-reporting and 15.7% based on medical history and HTN measurements. Of the participants with HTN, 297 (18.8%) had no knowledge of their disease, and 313 (19.9%) had not properly controlled their HTN despite receiving treatment. The sensitivity, specificity, and kappa for self-reported HTN were 75.5%, 96.4%, and 73.4%, respectively. False positives became more likely with age, body mass index (BMI), low socioeconomic status, and female sex, whereas false negatives became more likely with age, BMI, high socioeconomic status, smoking, and urban residency. Conclusions: The sensitivity and specificity of self-reported HTN were acceptable, suggesting that this method can be used for public health initiatives in the absence of countrywide HTN control and detection programs.

• Clinical and Experimental Pediatrics
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• v.51 no.9
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• pp.971-976
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• 2008

Purpose : Surveillance for detecting and managing latent tuberculosis infection (LTBI) is a key component of tuberculosis control. The classic surveillance tool, the tuberculin skin test (TST), may have some limitations when used in the Bacillus Calmette-$Gu{\acute{e}}rin$ (BCG)-vaccinated population. The object was to perform a blood test $QuantiFERON^{(R)}$-TB Gold In Tube (QFT-G IT) based on the detection of interferon-$\gamma$ ($IFN-{\gamma}$) released by T cells in response to Mycobacterium tuberculosis-specific antigens, and to compare the efficacy of this new diagnostic tool for LTBI with that of TST. Methods : For six months, between October 1, 2006 and April 30, 2007, data were collected from 111 patients under 15 years of age at Severance Children's Hospital. TST and QFT-G IT tests were performed with children with or without contact histories of tuberculosis. In addition to these tests, we examined comparative data from 29 adults who had tuberculosis, to detect false negative rates in the QFT-G IT method. Results : Thirty-three children had household contact histories. In this group, 15% and 42% of cases were found to be positive using the QFT-G IT assay and TST, respectively. Agreement was low between these two tests (${\kappa}=0.39$). In the adult active tuberculosis group, the QFT-G IT false negative rate defined as a positive culture and a negative QFT-G IT result was 12.5%. Conclusion : In diagnosing LTBI in children, the usefulness of a whole-blood $IFN-{\gamma}$ assay employing TB-specific antigens will be revealed only by examining additional longitudinal clinical data; this study serves as a starting point in that process.