• 대한환경공학회지
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• 제30권2호
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• pp.155-160
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• 2008

본 연구에서는 다단계 전기화학적 반응기를 이용하여 환원제의 투입, 전극의 종류, 수리학적 체류시간(HRT : Hydraulic Retention Time) 및 전류밀도 변화에 따른 질산성질소의 제거효율을 살펴보았다. 실험결과, 환원제 투입은 질산성질소 제거효율을 증가시켰으며 에너지투입량은 감소시켰다. 전극종류를 변화시켰을 경우, 질산성질소 제거효율 및 전류효율의 차이는 거의 없었으나 Zn 환원제의 회수를 위해 B-type(1단 : Pt-Zn, 2단 : Pt-Zn, 3단 : Pt-Zn, 4단 : Pt-Zn)을 선정하였다. 수리학적 체류시간 변화실험에서는 수리학적 체류시간과 무관하게 동일전류밀도를 공급한 실험과 수리학적 체류시간 변화에 따른 전류밀도 변화 실험 즉, 단위부피당 동일 전류량 공급 실험을 진행하였다. 실험 결과, 수리학적 체류시간과 전류밀도 변화에 의해 농도분극현상과 적용전류량의 부족현상이 발생하게 된다. 즉 수리학적 체류시간이 감소할수록 농도분극현상은 감소하지만 단위 부피당 적용전류량이 부족하게 된다. 따라서 수리학적 체류시간과 전류밀도 실험을 통해 적절한 운전조건을 도출할 수 있으며, 내부 스페이서의 설치로 확산을 증가시킬 경우 질소제거효율 및 에너지효율이 증가될 수 있을 것으로 예상된다.

• BMB Reports
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• 제51권11호
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• pp.584-589
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• 2018

Secondary prevention via earlier detection would afford the greatest chance for a cure in premalignant lesions. We investigated the exomic profiles of non-malignant and malignant changes in head and neck squamous cell carcinoma (HNSCC) and the genomic blueprint of human papillomavirus (HPV)-driven carcinogenesis in oropharyngeal squamous cell carcinoma (OPSCC). Whole-exome (WES) and whole-genome (WGS) sequencing were performed on peripheral blood and adjacent non-tumor and tumor specimens obtained from eight Korean HNSCC patients from 2013 to 2015. Next-generation sequencing yielded an average coverage of $94.3{\times}$ for WES and $35.3{\times}$ for WGS. In comparative genomic analysis of non-tumor and tumor tissue pairs, we were unable to identify common cancer-associated early mutations and copy number alterations (CNA) except in one pair. Interestingly, in this case, we observed that non-tumor tonsillar crypts adjacent to HPV-positive OPSCC appeared normal under a microscope; however, this tissue also showed weak p16 expression. WGS revealed the infection and integration of high-risk type HPV16 in this tissue as well as in the matched tumor. Furthermore, WES identified shared and tumor-specific genomic alterations for this pair. Clonal analysis enabled us to infer the process by which this transitional crypt epithelium (TrCE) evolved into a tumor; this evolution was accompanied by the subsequent accumulation of genomic alterations, including an ERBB3 mutation and large-scale CNAs, such as 3q27-qter amplification and 9p deletion. We suggest that HPV16-driven OPSCC carcinogenesis is a stepwise evolutionary process that is consistent with a multistep carcinogenesis model. Our results highlight the carcinogenic changes driven by HPV16 infection and provide a basis for the secondary prevention of OPSCC.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5773-5777
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• 2015

Background: Oral squamous cell carcinoma (OSCC) is thought to develop from precancerous dysplastic lesions through multistep processes of carcinogenesis involving activation of oncogenes and loss of tumor suppressor genes. The human epidermal growth factor receptor 2 (Her-2/neu [erbB-2]), a cell membrane glycoprotein, is a growth factor receptor that has receptor tyrosine kinase activity. Her2/neu activation plays a central role in cell proliferation and survival. It has been shown that overexpression of Her2/neu increases the rate of cell division and growth, leading to precancerous changes. The aim of the present study was to compare the serum and salivary Her2/neu levels between cases with premalignant and malignant oral lesions. Materials and Methods: Fasting blood samples and unstimulated saliva by passive drooling were collected from three groups of healthy control (n=20), premalignant disorder (PMD) (n=20) and OSCC (n=25) subjects. The HER2 extracellular domain (HER2 ECD) levels were measured using ELISA. Results: The levels of serum Her2/neu showed no significant differences between any of the groups but on the other hand salivary Her2/neu levels were found to be significantly (p<0.05) higher when compared between control (median 68.7 pg/ml, range: 21.5 - 75.8) and OSCC (median 145.6 pg/ml, range: 45.1-191.1). A similar trend was observed when comparing between PMD (median 43.3, range: 22.1 -94.7) and OSCC with a statistical significance of p<0.05. Conclusions: Our study provided evidence of increased salivary Her2/neu in OSCC when compared to PMD and control which was not the case for serum levels. This suggests that probably Her2/neu is not highly amplified as in breast cancer so as to be reflected in serum. Since saliva is in local vicinity of the OSCC, even a mild increase might be mirrored. On the whole, this study proposes Her2/neu as marker for distinguishing premalignant and malignant conditions.

• Asian Pacific Journal of Cancer Prevention
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• 제13권7호
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• pp.3519-3528
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• 2012

Inhibitory effects of Maclura amboinenesis Bl, one plant used traditionally for the treatment of cancers, on metastatic potential of highly metastatic B16F10 melanoma cells were investigated in vitro. Cell proliferation was assessed using the MTT colorimetric assay. Details of metastatic capabilities including invasion, migration and adhesion of B16F10 melanoma cells were examined by Boyden Chamber invasion and migration, scratch motility and cell attachment assays, respectively. The results demonstrated that n-hexane and chloroform extracts exhibited potent anti-proliferative effects (p<0.01), whereas the methanol and aqueous extracts had less pronounced effects after 24 h exposure. Bioactivity-guided chromatographic fractionation of both active n-hexane and chloroform extracts led to the isolation of two main prenylated xanthones and characterization as macluraxanthone and gerontoxanthone-I, respectively, their structures being identified by comparison with the spectral data. Interestingly, both exhibited potent effective effects. At non-toxic effective doses, n-hexane and chloroform extracts (10 and $30{\mu}g/ml$) as well as macluraxanthone and gerontoxanthone-I (3 and $10{\mu}M$) significantly inhibited B16F10 cell invasion, to a greater extent than $10{\mu}m$ doxorubicin, while reducing migration of cancer cells without cellular cytotoxicity. Moreover, exposure of B16F10 melanoma cells to high concentrations of chloroform ($30{\mu}g/ml$) and geratoxanthone-I ($20{\mu}M$) for 24 h resulted in delayed adhesion and retarded colonization. As insights into mechanisms of action, typical morphological changes of apoptotic cells e.g. membrane blebbing, chromatin condensation, nuclear fragmentation, apoptotic bodies and loss of adhesion as well as cell cycle arrest in the G1 phase with increase of sub-G1 cell proportions, detected by Hoechst 33342 staining and flow cytometry were observed, suggesting DNA damage and subsequent apoptotic cell death. Taken together, our findings indicate for the first time that active n-hexane and chloroform extracts as well as macluraxanthone and gerontoxanthone-I isolated from Maclura amboinensis Bl. roots affect multistep of cancer metastasis processes including proliferation, adhesion, invasion and migration, possibly through induction of apoptosis of highly metastatic B16F10 melanoma cells. Based on these data, M. amboinensis Bl. represents a potential candidate novel chemopreventive and/or chemotherapeutic agent. Additionally, they also support its ethno-medicinal usage for cancer prevention and/or chemotherapy.

• Journal of Microbiology and Biotechnology
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• 제14권1호
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• pp.81-89
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• 2004

Tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and lymphotoxin-$\alpha$ (LT-$\alpha$, TNF-$\beta$) can initiate and perpetuate human diseases such as multiple sclerosis (MS), rheumatoid arthritis (RA), and insulin-dependent diabetes mellitus (IDDM). TNFs can be blocked by the use of soluble TNF receptors. However, since monomeric soluble receptors generally exhibit low affinity or function as agonists, the use of monomeric soluble receptors has been limited in the case of cytokines such as TNF-$\alpha$, TNF-$\alpha$, interleukin (IL)-1, IL-4, IL-6, and IL-13, which have adapted to a multi component receptor system. For these reasons, very high-affinity inhibitors were created for the purpose of a TNFs antagonist to bind the TNFR and trigger cellular signal by using the multistep polymerase chain reaction method. First, recombinant simple TNFR-Ig fusion proteins were constructed from the cDNA sequences encoding the extracellular domain of the human p55 TNFR (CD120a) and the human p75 TNFR (CD120b), which were linked to hinge and constant regions of human $IgG_1$ heavy chain, respectively using complementary primers (CP) encoding the complementary sequences. Then, concatameric TNFR-Ig fusion proteins were constructed using recombinant PCR and a complementary primer base of recombinant simple TNFR-Ig fusion proteins. For high level expression of recombinant fusion proteins, Chinese hamster ovary (CHO) cells were used with a retroviral expression system. The transfected cells produced the simple concatameric TNFR-Ig fusion proteins capable of binding TNF and inactivating it. These soluble versions of simple concantameric TNFR-Ig fusion proteins gave rise to multiple forms such as simple dimers and concatameric homodimers. Simple TNFR-1g fusion proteins were shown to have much more reduced TNF inhibitory activity than concatameric TNFR-Ig fusion proteins. Concatameric TNFR-Ig fusion proteins showed higher affinity than simple TNFR-Ig fusion proteins in a receptor inhibitor binding assay (RIBA). Additionally, concatameric TNFR-Ig fusion proteins were shown to have a progressive effect as a TNF inhibitor compared to the simple TNFR-Ig fusion proteins and conventional TNFR-Fc in cytotoxicity assays, and showed the same results for collagen induced arthritis (CIA) in mice in vivo.

• Journal of Preventive Medicine and Public Health
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• 제41권6호
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• pp.373-379
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• 2008

Objectives ; The objective of this study was to evaluate the prevalence of atrophic gastritis and intestinal metaplasia according to gender, age and Helicobacter pylori infection in a rural population in Korea. Methods: Between April 2003 and January 2007, 713 subjects (298 men and 415 women, age range: 18-85) among the 2,161 adults who participated in a population-based survey received gastrointestinal endoscopy. All the subjects provided informed consent. Multiple biopsy specimens were evaluated for the presence of atrophic gastritis and intestinal metaplasia. The presence of Helicobacter Pylori was determined using CLO and histology testing. Results ; The age-adjusted prevalence of atrophic gastritis was 42.7% for men and 38.1% for women and the prevalence of intestinal metaplasia was 42.5% for men and 32.7% for women. The prevalence of atrophic gastritis and intestinal metaplasia increased significantly with age for both men and women (p for trend<0.001). The age-adjusted prevalence of Helicobacter pylori was similar for men (59.0%) and women (56.7%). The subjects with Helicobacter pylori infection showed a significantly higher prevalence of intestinal metaplasia (44.3%) compared with that (26.8%) of the noninfected subjects (p<0.001). However, the prevalence of atrophic gastritis was not statistically different between the Helicobacter pylori-infected subjects and the noninfected individuals. Conclusions : Our findings suggest that the prevalence of atrophic gastritis and intestinal metaplasia is higher for a Korean rural population than that for a Western population; this may be related to the high incidence of gastric cancer in Koreans. Especially, the prevalence of intestinal metaplasia was high for the subjects with Helicobacter pylori infection. The multistep process of gastric carcinogenesis and the various factors contributing to each step of this process need to be determined by conducting future follow-up studies.

• 생명과학회지
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• 제26권12호
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• pp.1367-1375
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• 2016

Cilostazol은 phosphodiesterase III의 선택적 저해제로 알려져 있으며, 뇌졸중 치료에 일반적으로 사용되고 있다. Cilostazol을 처리한 경우, 국소 뇌허혈이 발생한 후에 혈관신생을 통해서 혈관형성이 향상된다는 것을 본 연구자들이 발표하였다. 혈관신생은 조직의 허혈상태를 극복하기 위해서 혈관재생을 촉진하는 중요한 과정으로써, 혈관내피세포의 증식, 이동, 모세관구조 형성의 다단계 과정으로 구성되어 있다. 이에 본 연구에서는 인간 뇌혈관내피세포를 이용하여 cilostazol이 혈관신생의 각 단계들에 어떤 영향을 미치는지 조사하였다. Cilostazol은 농도의존적으로 뇌혈관내피세포의 이동성을 촉진하였으나, 뇌혈관내피세포의 증식과 모세관구조 형성에는 영향을 미치지 않았다. Cilostazol이 세포이동을 조절하는 기전을 분석하기 위해서 cDNA microarray를 수행하였고, 세포이동에 관련성이 있는 5종의 후보 유전자들을 선택하여 real-time PCR을 통해 해당 유전자의 발현을 검증하였다. Cilostazol에 의해서 발현양이 조절되는 유전자들로써, phosphoserine aminotransferase 1 (PSAT1)와 CCAAT/enhancer binding protein ${\beta}$ ($C/EBP{\beta}$)은 발현이 증가하였고, tissue factor pathway inhibitor 2 (TFPI2), retinoic acid receptor responder 1 (RARRES1), RARRES3는 발현이 감소하였다. 이상의 결과를 통해서 cilostazol이 혈관내피세포의 이동을 촉진하여 혈관신생을 향상시킬 수 있음을 제안할 수 있으며, 뇌혈관내피세포에 대한 cilostazol의 조절기전에 대해서 더욱 상세히 규명을 한다면 혈관형성을 통하여 허혈성 질환을 치료할 수 있는 유용한 정보가 될 것으로 기대한다.

• Childhood Kidney Diseases
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• 제14권2호
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• pp.132-142
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• 2010

저칼륨혈증의 경우 약제 또는 백혈구 증가증 등에 의해서 칼륨이 일시적으로 세포내로 이동하는 재분포에 의해서 생기는 저칼륨혈증을 먼저 감별한다. 칼륨소실에 의한 결핍의 경우 소변 칼륨 농도 또는 TTKG를 구하고, 감소되어 있는 경우에는 칼륨의 신외성 손실, 칼륨 섭취의 부족 등을 감별한다. 증가되어 있는 경우 신장을 통한 칼륨의 소실을 생각하고, 고혈압이 동반되어 있지 않을 경우 산증과 관련된 경우, 구토에 의한 경우, 세뇨관에서의 칼륨 재흡수 장애 또는 칼륨의 분비가 증가되는 경우를 생각할 수 있다. 고혈압이 동반되어 있을 경우 혈장 레닌과 알도스테론을 측정하여 레닌이 증가되어 있을 경우, 혈장 레닌이 정상 또는 낮으면서 혈장 알도스테론만 증가한 경우, 혈장 알도스테론은 증가되어 있지 않지만 알도스테론 이외에 광물부신겉질호르몬의 작용이 증가하는 경우를 감별한다. 증상은 무기력, 경련, 근육통, 횡문근 융해증, 변비, 장폐쇄, 부정맥, 지각이상 등이 있다. 치료는 원인 질환의 치료 및 칼륨공급이다. 고칼륨혈증은 재분포에 의한 경우, 가성 고칼륨혈증, 진성 고칼륨혈증을 감별해야 한다. 진성 고칼륨혈증이면서 사구체 여과율이 감소되어 있는 경우 신부전 또는 체내 칼륨 부하가 증가하는 경우를 감별한다. 사구체 여과율이 15 mL/min/$1.73m^2$ 이상인 경우에는 혈장 레닌과 알도스테론을 검사한다. 모두 낮을 경우, 혈장 레닌은 정상이지만 알도스테론만 낮은 경우, 혈장 알도스테론의 농도는 정상이지만 알도스테론의 작용을 저해되는 경우 등을 감별해야 한다. 증상은 부정맥, 감각 이상, 허약 등이 있다. 치료는 calcium gluconate, 인슐린, 베타2작용제, 중탄산염, furosemide, resin, 투석 등이 있으며, 칼륨을 제한하고 원인 약물이 있을 경우 이를 중단해야 한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권1호
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• pp.69-75
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• 2006

Head and neck squamous cell carcinoma(HNSCC) is the sixth most common cancer among men in the developed world affecting the tongue, pharynx, larynx and oral cavity. HNSCC is thought to represent a multistep process whereby carcinogen exposure leads to genetic instability in the tissue and accumulation of specific genetic events, which result in dysregulation of proliferation, differentiation, and cell loss and the acquisition of invasive capacity. Despite therapeutic and diagnostic progress in oncology during the past decades, the prognosis of HNSCC remains poor. Thus it seems that finding a biological tumor markers which will increase the early diagnosis and treatment monitoring rates, is of paramount importance in respect to improving prognosis. In an effort to identify gene expression signatures that may serve as biomarkers, this study several genes were selected, such as H3,3A, S100A7, UCHL1, GSTP1, PAI-2, PLK, TGF${\beta}$1 and bFGF, and used 7 HNSCC cell lines that were established various anatomical sites, and also 17 other cancer cell lines were used for control group using real-time quantitative RT-PCR and immunocytochemical analysis with a monoclonal antibody. In this study, S100A7 showed a clearly restricted occurrence in tongue originated cell line, and GSTP1 expression level in the pharynx originated cell line was very increased, relative to corresponding other cell lines. These results suggest that S100A7 and GSTP1 genes' expression can occur during tongue and pharynx originated head and neck tumorigenesis and that genetic change is an important driving force in the carcinogenesis process. This data indicate that S100A7 and GSTP1 expression pattern in HNSCC reflect both diagnostic clue and biological marker. And this is provides a foundation for the development of site-specific diagnostic strategies and treatments for HNSCC.

• 생명과학회지
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• 제23권4호
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• pp.602-608
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• 2013

만성적인 염증이 다단계 발암과정에서 다면적인 역할을 하고 있음은 이미 잘 알려진 사실이다. 치주 질환의 원인은 구강 박테리아에서 분비되는 내독소들과 염증 유발인자들의 생성 등이 관여하는 다양한 요인들을 포함하며, 이는 잘못된 구강 위생 관리가 신체의 여러 가지 전신병적 원인과 연관되어 있음을 의미한다. 비위생적인 구강 상태와 연관된 만성 염증, 흡연, 알콜 섭취의 증가 등은 암의 발병 위험 요소로 작용함은 명확한 사실이다. 최근에는 구강 위생과 치아 손실이 위장관암, 폐암 및 췌장암 뿐만 아니라 혈구암 발병 증가와 직접적인 연관성이 있음이 밝혀졌다. 또한 흡연은 악성 질환 발병의 위험 요소로서 구강 위생의 강력한 위해요인임은 명백하며, 역학적 조사결과들에 의하면 구강 박테리아에 의한 치주 질환은 만성 염증을 통하여 흡연과 알콜 연관 발암원을 활성시킴으로서 다양한 암의 발병 위험 요소를 증가시킬 수 있는 것으로 나타났다. 따라서 암 뿐만 아니라 다른 다양한 질환의 예방을 위한 적절한 구강 관리는 필수적이다. 본 논문에서는 암예방을 위한 악성질환의 위해 요소로서 염증과 치주질환 및 구강 위생과의 연관성을 논하였다.