• Journal of Environmental Impact Assessment
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• v.29 no.4
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• pp.286-297
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• 2020

This research studied human health risk assessment of PAHs (Polycyclic Aromatic Hydrocarbons) in road dust sediments collected from 6 sites in four different cities in Korea. PAHs are well known to be human carcinogens and toxic compounds that are commonly generated from incomplete combustion of fuels and energy products. Such compounds which is absorbed by atmospheric suspended dust can be emitted into air in gaseous form and often deposited on road dust sediments. The PAHs which is deposited on sediment particles can also be re-dispersed by vehicles or winds on the road surface. It can be harmful for humans when exposed via breathing, ingestion and dermal contact. This study examined human health risk assessment of PAHs in deposited road dust sediments. Results showed that the excess cancer risk estimates were above 1.0×10-6 at main traffic roads and resident area in Ulsan city. According to the result of deterministic risk assessment, dermal-contact was the major pathway, while the contribution of the risk from inhalation was less than 1%. The probabilistic risk assessment showed similar levels of cancer risk derived from the deterministic risk assessment. The result of sensitivity analysis reveal that exposure time is the most contributing factor (69%). Since the values of carcinogenic risk assessment were higher than 1.0 × 10^-6, further detailed monitoring and refined risk assessment for PAHs may be required to identify more reliable and potential cancer risks for those who live in the study locations in Ulsan city.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.2
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• pp.289-295
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• 1998

Used gasoline engine oils(UGEO) are carcinogenic in long term studies and capable of increasing the number of carcinogen-DNA adducts in short term studies when dermally applied to mice. The carcinogenic risk of UGEO has been attributed to the concentration of polycyclic aromatic hydrocarbons(PAH) which accumulate in the lubricating system during the combustion of gasoline. When dermally exposed to UGEO, the use of hand cleanser was commonly recommended for removing it. But generally workers who dermally exposed oils, use kerosene as cleaner which make skin trouble. During this study, female mice aged 4-6 weeks were utilized to evaluate the efficiency of kerosene, as solvent-based cleanser, following dermal exposure to UGEO. DNA adduct were detected at skin and lung tissues by using the $^{32}P$-postlabeling method. Washing with cleansers were done at two different interval times following dermal application of UGEO. The total DNA adducts in skin and lung tissues were statistically significantly increased in positive control groups, and of which the total adduct level in skin tissues was statistically significant higher than those in lung tissues(p=0.005). When washing kerosene, the DNA adduct level in skin tissues was statistically significantly decreased(p=0.0001). But DNA adducts in lung tissue was statistically increased(p=0.0039), and that washed at 8hr post exposure was more severly increase(p<0.05). The slope of regression between DNA adducts of lung between skin tissues was 1.0802. In conclusion, skin cleaning with kerosene facilitates passage of carcinogens to the lungs of animals dermally treated with used gasoline engine oils(UGEO).

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1235-1240
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• 2012

Background: Opisthorchis viverrini infection is a serious public-health problem in Southeast Asia. It is associated with a number of hepatobiliary diseases and the evidence strongly indicates that liver fluke infection is the etiology of cholangiocarcinoma. Objectives: This study aimed to investigate Opisthorchis viverrini metacercarial infection in cyprinoid fish collected from 32 districts of Nakhon Ratchasima province, Northeastern Thailand during one year period from February 2010 to February 2011. Methods: A cross-sectional study was conducted, data being collected with pepsin-HCl digestion and stereomicroscope, respectively. Analysis was performed using SPSS Windows Version 12.0. Results: A total of 640 Cyprinidae family fish including 5 species were collected from different study sites, and investigated for O. viverrini metacercariae. The infection rate was 12.3% (79/640), predominantly in Cyclocheilichthys armatus, C. repasson, Puntioplites proctzysron, Hampala macrolepitota and Hampala dispar, respectively. The prevalence of O. viverrini metaceria in Nakhon Ratchasima area was 78.1%, predominantly in Sida and KiaKham Thale So. Conclusion: This findings stress that natural fish species in rural communities are still a source of O viverrini infection and put local people at risk, therefore public awareness and prevention campaigns are urgently required.

• Korean Journal of Head & Neck Oncology
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• v.25 no.1
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• pp.28-32
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• 2009

Background : The most frequently reported risk factors for head and neck suamous cell carcinoma are smoking and alcohol. But in a recent overview, human papilloma virus(HPV) infection was revealed the important carcinogenic factor in oropharyngeal cancer. We aimed to clarify whether HPV directly effects on the oncogenesis and biologic behavior of hean and neck squamous cell carcinoma by comparison with infection prevalence, and physical status of virus. Material and Method : We used HPV genotyping DNA chip(Biocore, Korea, Seoul) arrayed by multiple oligonucleotide probes of L1 sequence of 26 types of HPV and HPV genotypes are identified by fluorescence scanner. The copy numbers of HPV E2 and E6 open reading frames(ORF) were assessed using a TaqMan-based 5'-exonuclease quantitative real-time PCR assay. The ratio of E2 to E6 copy numbers was calculated to determine the physical status of HPV-16 viral gene. Results : We observed a significant difference in HPV prevalence between tonsillar cancer group and control group(73.1% vs. 11.6%), and most of the HPVs were type 16(87.2%) and integrated(94.1%) state. In terms of oral tongue cancer, we demonstrate that 30.5% has integrated HPV-16 in cancer tissue. But Glottic cancer only 1% is related to HPV-16 integration. Conclusion : This study revealed significant relationship of HPV prevalence with oropharyngeal and oral tongue squamous cell carcinoma. Most of HPV were 16 type and integrated or mixed, HPV-16 integration could be directly related to the carcinogenesis.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5817-5821
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• 2012

Background/Aims: Glutathione S-transferase M1 (GSTM1) is a multifunctional enzyme that plays a critical role in the detoxification of varieties of carcinogenic metabolites. Many studies have been conducted to investigate the association between GSTM1 polymorphism and nasopharyngeal cancer (NPC) risk, but the findings among those studies are inconsistent. To assess this relationship more precisely, we performed a meta-analysis of all available studies on the subject. Methods: Case-control studies were identified by searching Pubmed, Embase, ISI Web of Science, and Wanfang databases through September 6, 2012. We used the pooled odds ratio (OR) with its corresponding 95% confidence interval (95%CI) to evaluate the association of GSTM1 polymorphism with NPC susceptibility. Subgroup analyses by pathological types, sex and smoking status were performed to further identify the association. Results: Overall, 11 published studies with 1,513 cases and 2,802 controls were finally included into this meta-analysis according to the inclusion criteria. Meta-analysis of total studies showed that the null genotype of GSTM1 was significantly associated with increased risk of NPC, when comparing with the non-null genotype (OR=1.51, 95%CI=1.33-1.72, POR<0.001). The association was still statistically significant in subgroup analysis of patients with nasopharyngeal squamous cell carcinoma (OR=1.73, 95%CI=1.24-2.42, POR=0.001). Males with the null genotype of GSTM1 were more likely to subject to NPC than females. In addition, the association between the null genotype of GSTM1 and NPC risk was strongest in individuals with exposure to smoking. Sensitivity analysis by sequential omission of any individual studies one at a time further demonstrated the significant association. Conclusions: The findings suggest that the null genotype of GSTM1 is a risk factor for NPC, and there is a gene-smoking interaction in this association.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.1913-1917
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• 2015

Background: Oesophageal squamous cell carcinoma (ESCC) is endemic in the Eastern Anatolian region of Turkey. The present study was performed to identify risk factors for ESCC that specifically reflect the demography and nutritional habits of individuals living in this region. Materials and Methods: The following parameters were compared in 208 ESCC patients and 200 control individuals in the Eastern Anatolian region: age, sex, place of living, socioeconomic level, education level, smoking, alcohol intake, nutritional habits, and food preservation methods. Results: The mean age of ESCC patients was 56.2 years, and 87 (41.8%) were 65 years-old or older. The ratio of women to men in the patient group was 1.39/1. ESCC patients consumed significantly less fruit and yellow or green vegetables and more hot black tea, 'boiled yellow butter', and mouldy cheese than did control individuals. Residence in rural areas, smoking, and cooking food by burning animal manure were also significantly associated with ESCC. Conclusions: The consumption of boiled yellow butter and mouldy cheese, which are specific to the Eastern Anatolian region, and the use of animal manure for food preparation were identified as risk factors in this region. Further studies are required to potentially identify the carcinogenic substances that promote the development of ESCC in this region.

• Safety and Health at Work
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• v.15 no.1
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• pp.87-95
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• 2024

Background: This study focuses on assessing occupational risk for the health hazards encountered during maintenance works (MW) in semiconductor fabrication (FAB) facilities. Objectives: The objectives of this study include: 1) identifying the primary health hazards during MW in semiconductor FAB facilities; 2) reviewing the methods used in evaluating the likelihood and severity of health hazards through occupational health risk assessment (OHRA); and 3) suggesting variables for the categorization of likelihood of exposures to health hazards and the severity of health effects associated with MW in FAB facilities. Methods: A literature review was undertaken on OHRA methodology and health hazards resulting from MW in FAB facilities. Based on this review, approaches for categorizing the exposure to health hazards and the severity of health effects related to MW were recommended. Results: Maintenance workers in FAB facilities face exposure to hazards such as debris, machinery entanglement, and airborne particles laden with various chemical components. The level of engineering and administrative control measures is suggested to assess the likelihood of simultaneous chemical and dust exposure. Qualitative key factors for mixed exposure estimation during MW include the presence of safe operational protocols, the use of air-jet machines, the presence and effectiveness of local exhaust ventilation system, chamber post-purge and cooling, and proper respirator use. Using the risk (R) and hazard (H) codes of the Globally Harmonized System alongside carcinogenic, mutagenic, or reprotoxic classifications aid in categorizing health effect severity for OHRA. Conclusion: Further research is needed to apply our proposed variables in OHRA for MW in FAB facilities and subsequently validate the findings.

• Biomedical Science Letters
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• v.20 no.4
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• pp.185-193
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• 2014

Cancers are based upon an array of orchestrated genetic changes and the identification of changes causally related to the carcinogenic process. To elucidate the mechanism of cancer carcinogenesis, it is necessary to reconstruct these molecular events at each level. Microarray technologies have been extensively used to evaluate genetic alterations associated with cancer onset and progression in clinical oncology. The clinical impact of the genomic alterations identified by microarray technologies are growing rapidly and array analysis has been evolving into a diagnostic tool to better identify high-risk patients and predict patient outcomes from their genomic profiles. Here, we discuss the state-of-the-art microarray technologies and their applications in clinical oncology, and describe the potential benefits of these analysis in the clinical implications and biological insights of cancer biology.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4199-4204
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• 2016

Cancer is a complex disease caused by a progressive accumulation of multiple genetic mutations. Consumption of fruits is associated with lower risk of several cancers, which is mainly associated to their phytochemical content. The use of functional foods and chemopreventive compounds seems to contribute in this process, acting by mechanisms of antioxidant, anti-inflammatory, anti-angiogenic and hormonal. The Psidium Guajava has high potential functional related to pigments who are involved in the process of cancer prevention by having antioxidant activity. The aim of the present review is to expose some chemical compounds from P. Guajava fractions and their association with anti-carcinogenic function. The evidences supports the theory of anticancer properties of P. Guajava, although the mechanisms are still not fully elucidated, but may include scavenging free radicals, regulation of gene expression, modulation of cellular signalling pathways including those involved in DNA damage repair, cell proliferation and apoptosis.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.2
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• pp.102-106
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• 2008

Formaldehyde, an indoor volatile organic compound, is considered toxic due to its carcinogenic risk. Recently, we isolated a formaldehyde-degrading bacterium Pseudomonas sp. YK-32. A crude enzyme prepared from YK-32 also degraded formaldehyde, suggesting that YK-32 cells have formaldehyde hydrogenase activity which is one of the important factors in formaldehyde degradation. The formaldehyde hydrogenase activity was increased 1.25 fold by adding 0.1 % glucose and formaldehyde to the culture medium. In addition, treatment with 1 mM EDTA as a permeabilizer promoted the degradation of formaldehyde and increased the enzymatic activity.