• 제목/요약/키워드: Basic Medical Science

검색결과 1,251건 처리시간 0.026초

Cloning and Biochemical Characterization of a Hyaluronate Lyase from Bacillus sp. CQMU-D

  • Lu Wang;Qianqian Liu;Xue Gong;Wenwen Jian;Yihong Cui;Qianying Jia;Jibei Zhang;Yi Zhang;Yanan Guo;He Lu;Zeng Tu
    • Journal of Microbiology and Biotechnology
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    • 제33권2호
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    • pp.235-241
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    • 2023
  • Hyaluronidase (HAase) can enhance drug diffusion and dissipate edema by degrading hyaluronic acid (HA) in the extracellular matrix into unsaturated HA oligosaccharides in mammalian tissues. Microorganisms are recognized as valuable sources of HAase. In this study, a new hyaluronate lyase (HAaseD) from Bacillus sp. CQMU-D was expressed in Escherichia coli BL21, purified, and characterized. The results showed that HAaseD belonged to the polysaccharide lyase (PL) 8 family and had a molecular weight of 123 kDa. HAaseD could degrade chondroitin sulfate (CS) -A, CS-B, CS-C, and HA, with the highest activity toward HA. The optimum temperature and pH value of HAaseD were 40℃ and 7.0, respectively. In addition, HAaseD retained stability in an alkaline environment and displayed higher activity with appropriate concentrations of metal ions. Moreover, HAaseD was an endolytic hyaluronate lyase that could degrade HA to produce unsaturated HA oligosaccharides. Together, our findings indicate that HAaseD from Bacillus sp. CQMU-D is a new hyaluronate lyase and with excellent potential for application in industrial production.

우리나라 의사 국가시험 필기시험(2016-2018)의 기초의학 역량 평가 현황의 분석 (Analysis of Basic Medicine-Related Questions in the Korean Medical Licensing Examination (2016-2018))

  • 국현;오세옥;이덕주;기선호;전용성
    • 의학교육논단
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    • 제25권1호
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    • pp.68-77
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    • 2023
  • Basic medical education is important for developing the competencies of medical doctors, and it includes basic biomedical sciences, preventive medicine, medical ethics, and clinical science. This study aimed to reveal the current status of the Korean Medical Licensing Examination (KMLE) regarding its evaluation of competencies in basic biomedical sciences. The basic medicine-related questions were screened and selected from the test forms of the KMLE (2016-2018) by personnel conducting basic biomedical science education, and the selected questions were analyzed by three independent groups of undergraduate students at Chonnam National University Medical School in terms of the learning outcomes of basic medical education. The study scope includes the proportion of basic medicine-related questions, which consist of basic medicine questions and basic medicine-related clinical medicine questions, its annual change, discipline distribution, and associated learning outcomes. The average proportions of basic biomedical sciences, preventive medicine and medical law, and clinical sciences were 2.3%, 5.8%, and 91.9% of all questions, respectively. The proportion of basic medicine-related questions, except those on preventive medicine and medical law, was 22.0% of the total, and questions on pharmacology and microbiology accounted for 83.0% of the basic medicine-related questions. The proportion of sub-enabling learning outcomes linked with basic medicine-related questions comprised 14.0% of the total outcomes for basic biomedical sciences and 30.4% for preventive medicine and medical law. It is concluded that the KMLE questions may not sufficiently cover the essential competencies of basic medical education for medical doctors, and the KMLE may need to be improved with regard to competencies in basic biomedical sciences.

BRI3 associates with SCG10 and attenuates NGF-induced neurite outgrowth in PC12 cells

  • Gong, Yanhua;Wu, Jing;Qiang, Hua;Liu, Ben;Chi, Zhikai;Chen, Tao;Yin, Bin;Peng, Xiaozhong;Yuan, Jiangang
    • BMB Reports
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    • 제41권4호
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    • pp.287-293
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    • 2008
  • In a yeast two-hybrid screen, we identified the microtubule-destabilizing protein SCG10 as a potential effector protein of $BRI_3$. The association was verified using GST pull-down, Co-IP, and their perinuclear co-localization. The analysis of in vitro microtubule polymerization/depolymerization showed that the binding of $BRI_3$ to SCG10 effectively blocked the ability of SCG10 to induce microtubule disassembly, as determined by turbidimetric assays. In intact PC12 cells, $BRI_3$ exhibited the ability to stabilize the microtubule network and attenuate the microtubule-destabilizing activity of SCG10. Furthermore, co-expression of $BRI_3$ with SCG10 attenuated SCG10-mediated PC12 cell neurite outgrowth induced by NGF. These results identify a novel connection between a neuron-specific BRI protein and the cytoskeletal network, suggesting possible roles of BRI3 in the process of neuronal differentiation.

Autophagy inhibition through PI3K/Akt increases apoptosis by sodium selenite in NB4 cells

  • Ren, Yun;Huang, Fang;Liu, Yuan;Yang, Yang;Jiang, Qian;Xu, Caimin
    • BMB Reports
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    • 제42권9호
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    • pp.599-604
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    • 2009
  • Selenium possesses the chemotherapeutic feature by inducing apoptosis in cancer cell with trivial side effects on normal cells. However, the mechanism in which is not clearly understood. Emerging evidence indicates the overlaps between the autophagy and the apoptosis. In this study, we have investigated the role of autophagy in selenium-induced apoptosis in NB4 cells. We find that autophagy is suppressed in NB4 cells treated by sodium selenite, as measured by electron microscope, acridine orange staining and western blot. Moreover, selenite combined with autophagy inhibitor contributes to the up-regulation of apoptosis, while the PI3K/Akt signaling pathway is down- regulated. Consistently, when the inhibitor of PI3K was applied, the autophagic level significantly decreased. In summary, sodium selenite increases NB4 cell apoptosis by autophagy inhibition through PI3K/Akt, and the inhibition of autophagy contributes to the up-regulation of apoptosis.

ER membrane protein complex subunit 6 (EMC6) is a novel tumor suppressor in gastric cancer

  • Wang, Xiaokun;Xia, Yan;Xu, Chentong;Lin, Xin;Xue, Peng;Zhu, Shijie;Bai, Yun;Chen, Yingyu
    • BMB Reports
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    • 제50권8호
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    • pp.411-416
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    • 2017
  • The endoplasmic reticulum (ER) membrane protein complex subunit 6 (EMC6) is a novel human autophagy-related molecule. Here, using tissue microarray and immunohistochemistry, we report that EMC6 protein is lost or reduced in glandular cells of patients with gastric adenocarcinoma, compared to normal stomach mucosa. Overexpression of EMC6 in gastric cancer cells inhibited cell growth, migration, invasion, and induced apoptosis and cell cycle arrest at S-phase. Further investigation suggested that EMC6 overexpression in BGC823 human adenocarcinoma gastric cancer cells reduced tumorigenicity in a xenograft model, demonstrating that EMC6 has the characteristics of a tumor suppressor. This is the first study to show that EMC6 induces cell death in gastric cancer cells. The molecular mechanism of how EMC6 functions as a tumor suppressor needs to be further explored.

Detection of MecA Gene in Clinical Isolates of Staphylococcus aureus by Multiplex-PCR, and Antimicrobial Susceptibility of MRSA

  • Lee, Hyean-Woo;Yoon, Joon-Ho;Sohn, Joon-Hyung;Lee, Kyoung-Ho;Yeh, Byung-Il;Park, Deok-Woo;Kim, Hyun-Won;Choi, Jong-Whan
    • Journal of Microbiology and Biotechnology
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    • 제13권3호
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    • pp.354-359
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    • 2003
  • Multiplex-PCR protocols were designed in order to make a rapid identification of MRSA. MecA, femB, and 165 rRNA genes were amplified for making a detection of MRSA. The incidence of MRSA in the clinical isolates of Staphylococcus aureus was examined by using a multiplex-PCR assay. The mecA gene was detected in 266 strains out of 336 clinical isolates of S. aureus, thus the incidence of MRSA was approximately 76.5%. The MRSAs of 247 strains (96.1%) showed resistance to more than eight species of the antimicrobial agents tested. The isolates of MRSA showed 27 different antimicrobial-resistant patterns. The results indicate that many different MRSA strains having high multidrug resistance are actually prevalent in Korea. Also, VISA was screened from the MRSA. Two strains were grown on the BHI agar plate supplemented with $8\;\mu\textrm{g}/ml$ of vancomycin at a frequency of $1/10^8$ colony forming units or higher.