• Journal of Microbiology and Biotechnology
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• 제25권4호
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• pp.547-553
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• 2015

The yeast surface-displayed cDNA library has been used to identify unknown antigens. However, when unknown target antigens show moderate-to-low abundance, some modifications are needed in the screening process. In this study, a directional random-primed cDNA library was used to increase the number of candidates for the unknown antigen. To avoid the loss of target yeast clones that express proteins at a low frequency in the cDNA library, a comprehensive monitoring system based on magnetic-activated cell sorting, fluorescence-activated cell sorting, and immunofluorescence was established, and a small number of target yeast cells was successfully enriched. These results showed that our optimized method has potential application for identifying rare unknown antigens of the human monoclonal antibody.

• 약학회지
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• 제44권5호
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• pp.416-423
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• 2000

There is a growing concern that a wide variety of chemicals released into the environment can disrupt the endocrine system of fish, wildlife and humans. Endocrine disrupting chemicals (EDCs) include pesticides such as DDT lindane and atrazine, the food packaging chemicals, phthalates and bisphenol A, alkylphenol ethoxylate detergents and the chemical industry by-products, dioxins. Xenoestrogens in the environment have been argued about health risk, because of estrogen mimetic chemicals are exposed only small amounts to human. A number of in vivo and in vitro assays are now in use to assess the activity of xenoestrogens in the environment. A human breast cancer cell line (MCF-7) was used to develop in vitro screening assay for the detection of xenoestrogenic environmental pollutants. The E-SCREEN (MCF7-BUS) assay is proposed as a reliable, easy and rapid-to-perform method. To optimize and validate this method before it can be used routinely, several phenol compounds and pesticides suspected to be estrogenic were tested using I-SCREEN assay. The results showed that this method is a valuable tool for screening potential estrogen-mimicking environmental pollutants and quantitative determination of estrogeniciy.

• Molecules and Cells
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• 제27권5호
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• pp.577-582
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• 2009

The development of a high-throughput functional genomic screening provides a novel and expeditious approach in identifying critical genes involved in specific biological processes. Here we describe a cell-based cDNA screening system to identify the transcription activators of BiP, an endoplasmic reticulum (ER) chaperone protein. BiP promoter contains the ER stress element which is commonly present in the genes involved in unfolded protein response (UPR) that regulates protein secretion in cells. Therefore, the positive regulators of BiP may also be utilized to improve the recombinant protein production through modulation of UPR. Four BiP activators, including human UDP-glucose:glycoprotein glucosyltransferase 1 (HUGT1), are identified by the cDNA screening. Overexpression of HUGT1 leads to a significant increase in the production of recombinant erythropoietin, interferon ${\gamma}$, and monoclonal antibody in HEK293 cells. Our results demonstrate that the cDNA screening for BiP activators may be effective to identify the novel BiP regulators and HUGT1 may serve as an ideal target gene for improving the recombinant protein production in mammalian cells.

• 약학회지
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• 제39권4호
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• pp.444-449
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• 1995

Primary cultures of rat cortical and chicken embryonic brain cells were employed to establish a reliable screening method for natural products blocldng or enhancing glutamate-induced neurotoxicity. Exposure of primary cultured rat cortical cells or chicken embryonic brain cells to high dose of glutamate resulted in the fragmentation of neutites and consequent neuronal death. The level of cytoplasmic lactate dehydrogenase(LDH), indicator for cell survival in cultures, was significantly reduced at exposure to glutamate. For the practical application of the methods, series of concentrations of plants extracts and positive control were applied prior to the glutamate insult on primary cultures of rat cortical and chicken embryonic, brain cells. Relative LDH level in cells was measured for the estimation of the effect of the test materials on the glutamatergic neurons. The validity of the present screening method for natural products acting on glutamatergic neurons was examined with dextromethorphan, a known glutamatergic antagonist. The treatment of 100 $\mu{M}$ dextromethorphan prevented the reduction of LDH in rat cortical and chicken embryonic brain cells caused by glutamate insult keeping 60% and 90% of LDH level in normal control, respectively. Above results indicate that primary cultures of rat cortical and chicken embryonic brain cells could be proper systems for the screening of potential natural agents acting on glutamatergic, neurons. Between the two types of cultures, primary culture of chicken embryonic brain cells seemed to be a better system for the primary screening, since it is technically easier and economical compared to that of rat cortical cells.

• Asian Pacific Journal of Cancer Prevention
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• 제16권6호
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• pp.2307-2312
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• 2015

Curcumol is a sesquiterpene originally isolated from curcuma rhizomes, a component of herbal remedies commonly used in oriental medicine. Its beneficial pharmacological activities have attract significant interest recently. In this study, anti-cancer activity of curcumol was examined with both in vitro and in vivo models. It was found that curcumol exhibited time- and concentration-dependent anti-proliferative effects in SPC-A-1 human lung adenocarcinoma cells with cell cycle arrest in the G0/G1 phase while apoptosis-induction was also confirmed with flow cytometry and morphological analyses. Interestingly, curcumol did not display growth inhibition in MRC-5 human embryonic lung fibroblasts, suggesting the anti-proliferative effects of curcumol were specific to cancer cells. Anti-neoplastic effects of curcumol were also confirmed in tumor bearing mice. Curcumol (60 mg/ kg daily) significantly reduced tumor size without causing notable toxicity. In conclusion, curcumol appears a favorable anti-cancer candidate for further development.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4457-4461
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• 2016

Purpose: To determine the prevalence of abnormal cervical cytology, as diagnosed using a liquid-based cytology technique, in pregnant women attending the Antenatal Care (ANC) clinic at Siriraj Hospital. Materials and Methods: This cross-sectional study included 655 first-visit pregnant women who attended ANC clinic at Siriraj Hospital during June to November 2015 study period. After receiving routine antenatal care, cervical cytology screening was performed with the Siriraj liquid-based cytology technique. All specimens were reviewed by a certified cytopathologist using Bethesda System 2001 criteria. Patients with abnormal PAP results characterized as epithelial cell abnormalities were referred to a gynecologic oncologist for further management according to ASCCP Guidelines 2012. Results: Mean age of participants was $28.9{\pm}6.2$ years. Prevalence of abnormal cervical cytology was 3.4% (95% CI: 2.0-4.7). Among this group, there were ASC-US, ASC-H, LSIL, HSIL for 12(1.8%), 2(0.3%), 7(1.1%) and 1(0.2%), respectively. In 633 specimens of the normal group, infection was identified in 158 specimens (24.1%) which were caused by Candida spp. and Trichomonas vaginalis. Regarding patient perception about the importance of cervical cancer screening, although most women perceived screening to be important, 54% of participants had never been screened for cervical cancer. Rate of loss to follow-up in the postpartum period was as high as 41.8%. Conclusions: Prevalence of abnormal cervical cytology in pregnant women attending the ANC clinic at Siriraj Hospital was 3.4%. Inclusion of cervical cancer screening as part of antenatal assessment can help to identify precancerous lesions or cervical cancers in patients who might otherwise not be screened, thereby facilitating early treatment and improved patient outcomes.

• Asian Pacific Journal of Cancer Prevention
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• 제13권10호
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• pp.4931-4933
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• 2012

Objective: To determine the diagnostic performance of hematuria as a screening test for urinary bladder infiltration in cervical cancer patients with a prospective study design. Materials and Methods: Newly diagnosed cervical cancer patients at Srinagarind hospital from 14 June 2011 to 30 April 2012 were enrolled in this study. We collected midstream urine samples for urinalysis from every patient before routine cystoscopic exam for clinical staging. The presence of 3 or more red blood cells (RBCs) per high power field was defined as positive for hematuria. A two-by-two table was used to determine the diagnostic performance of hematuria to detect urinary bladder mucosal infiltration using cystoscopy and biopsy as the gold standard. Result: A total of 130 were patients included, 54 of which (41.5%) had hematuria. Of these, four patients (3.08%) had pathological report from cystoscopic biopsy confirmed metastatic squamous cell carcinoma. The sensitivity, specificity, PPV, NPV, and accuracy of hematuria as a screening test to detect urinary bladder mucosal infiltration of cervical cancer were 100%, 60.3%, 7.4%, 100%, and 61.5%, respectively. There was no single case of urinary bladder mucosal infiltration in patients initially staged less than stage III. Conclusions: Hematuria can be used as a screening test to detect urinary bladder mucosal infiltration of cervical cancer. This can reduce the number of cervical cancer patients who really need to undergo cystoscopy as a staging procedure to less than half and to less than 20% if stage III or more were included without missing a single case of urinary bladder mucosal infiltration.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.2979-2982
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• 2013

Cervical cancer is a commonly-encountered malignant tumor in women. Cervical screening is particularly important due to early symptoms being deficient in specificity. The main purpose of the study is to assess the application value of cervical thinprep cytologic test (TCT) and human papillomavirus (HPV) detection in screening for cervical cancer and precancerous lesions. In the study, cervical TCT and HPV detection were simultaneously performed on 12,500 patients selected in a gynecological clinic. Three hundred patients with positive results demonstrated by cervical TCT and/or HPV detection underwent cervical tissue biopsy under colposcopy, and pathological results were considered as the gold standard. The results revealed that 200 out of 12,500 patients were abnormal by TCT, in which 30 cases pertained to equivocal atypical squamous cells (ASCUS), 80 cases to low squamous intraepithelial lesion (LSIL), 70 cases to high squamous intraepithelial lesion (HSIL) and 20 cases to squamous cell carcinoma (SCC). With increasing pathological grade of cervical biopsy, however, TCT positive rates did not rise. Two hundred and eighty out of 12,500 patients were detected as positive for HPV infection, in which 50 cases were chronic cervicitis and squamous metaplasia, 70 cases cervical intraepithelial neoplasia (CIN) I, 60 cases CIN II, 70 cases CIN III and 30 cases invasive cervical carcinoma. Two hundred and thirty patients with high-risk HPV infection were detected. With increase in pathological grade, the positive rate of high-risk HPV also rose. The detection rates of HPV detection to CIN III and invasive cervical carcinoma as well as the total detection rate of lesions were significantly higher than that of TCT. Hence, HPV detection is a better method for screening of cervical cancer at present.

• 한국환경농학회지
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• 제20권2호
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• pp.74-78
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• 2001

아닐린을 유일 탄소원 및 에너지원으로 이용하는 두 개의 균주를 강물에서 분리하였다. 두 개의 세균 균주들은 생리 ${\cdot}$ 생화학적 특성과 16S rRNA 유전자 염기서열을 통하여 모두 Pseudomonas rhodesiae로 동정되었다. 이 균주들은 유일 탄소원으로 아닐린이 6,000 ${\mu}g/mL$ 수준으로 포함되어 있는 최소배지에서도 생육이 가능하였으며 두 균주간의 아닐린 분해능에는 뚜렷한 차이가 없었다. P. rhodesiae 51-C 균주는 아닐린이 300 ${\mu}g/mL$ 수준으로 처리된 최소배지에서 16시간이내에 아닐린을 완전히 분해하였고 아닐린 분해에 대한 최적의 pH는 7.0이었으며, 적온은 $30^{\circ}C$와 $35^{\circ}C$사이였다. P. rhodesiae에 의한 아닐린의 분해는 처음으로 보고하는 바이다.

• Journal of Microbiology and Biotechnology
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• 제33권3호
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• pp.329-338
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• 2023

Enterohemorrhagic Escherichia coli (EHEC) is a foodborne pathogen that produces attaching and effacing lesions on the large intestine and causes hemorrhagic colitis. It is primarily transmitted through the consumption of contaminated meat or fresh produce. Similar to other bacterial pathogens, antibiotic resistance is of concern for EHEC. Furthermore, since the production of Shiga toxin by this pathogen is enhanced after antibiotic treatment, alternative agents that control EHEC are necessary. This study aimed to discover alternative treatments that target virulence factors and reduce EHEC toxicity. The locus of enterocyte effacement (LEE) is essential for EHEC attachment to host cells and virulence, and most of the LEE genes are positively regulated by the transcriptional regulator, Ler. GrlA protein, a transcriptional activator of ler, is thus a potential target for virulence inhibitors of EHEC. To identify the GrlA inhibitors, an in vivo high-throughput screening (HTS) system consisting of a GrlA-expressing plasmid and a reporter plasmid was constructed. Since the reporter luminescence gene was fused to the ler promoter, the bioluminescence would decrease if inhibitors affected the GrlA. By screening 8,201 compounds from the Korea Chemical Bank, we identified a novel GrlA inhibitor named Grlactin [3-[(2,4-dichlorophenoxy)methyl]-4-(3-methylbut-2-en-1-yl)-4,5-dihydro-1,2,4-oxadiazol-5-one], which suppresses the expression of LEE genes. Grlactin significantly diminished the adhesion of EHEC strain EDL933 to human epithelial cells without inhibiting bacterial growth. These findings suggest that the developed screening system was effective at identifying GrlA inhibitors, and Grlactin has potential for use as a novel anti-adhesion agent for EHEC while reducing the incidence of resistance.