• Journal of Microbiology
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• 제45권1호
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• pp.21-28
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• 2007

In order to search for specific genotypes related to this unique phenotype, we used whole genomic DNA microarray to characterize the genomic diversity of Helicobacter pylori (H. pylori) strains isolated from clinical patients in China. The open reading frame (ORF) fragments on our microarray were generated by PCR using gene-specific primers. Genomic DNA of H. pylori 26695 and J99 were used as templates. Thirty-four H. pylori isolates were obtained from patients in Shanghai. Results were judged based on In(x) transformed and normalized Cy3/Cy5 ratios. Our microarray included 1882 DNA fragments corresponding to 1636 ORFs of both sequenced H. pylori strains. Cluster analysis, revealed two diverse regions in the H. pylori genome that were not present in other isolates. Among the 1636 genes, 1091 (66.7%) were common to all H. pylori strains, representing the functional core of the genome. Most of the genes found in the H. pylori functional core were responsible for metabolism, cellular processes, transcription and biosynthesis of amino acids, functions that are essential to H. pylori's growth and colonization in its host. In contrast, 522 (31.9%) genes were strain-specific genes that were missing from at least one strain of H. pylori. Strain-specific genes primarily included restriction modification system components, transposase genes, hypothetical proteins and outer membrane proteins. These strain-specific genes may aid the bacteria under specific circumstances during their long-term infection in genetically diverse hosts. Our results suggest 34 H. pylori clinical strains have extensive genomic diversity. Core genes and strain-specific genes both play essential roles in H. pylori propagation and pathogenesis. Our microarray experiment may help select relatively significant genes for further research on the pathogenicity of H. pylori and development of a vaccine for H. pylori.

• 한국수정란이식학회지
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• 제24권1호
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• pp.39-45
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• 2009

This study was carried out to evaluate the nuclear, cytoplasmic maturation and developmental potential of bovine oocytes selected by brilliant cresyl blue (BCB) as indirect measurement of oocytes growth phase. Cumulus-oocyte complexes (COCs) were collected from 2 to 8 mm follicles from slaughterhouse Hanwoo ovaries. The COCs were divided into stained cytoplasm to blue (BCB+) and unstained (BCB-) according to their ooplasm BCB coloration stained by $26{\mu}m$ of BCB after 90 min. Selected COCs were cultured in a TCM 199 for 18 to 26 h. Nuclear maturation and total cell number was evaluated after in vitro maturation (IVM) or in vitro culture (IVC) using $10{\mu}g/ml$ Hoechst 33342, and cytoplasmic maturation was evaluated by intracellular glutathione (GSH) assay before (0 h) and after (24 h) IVM. The oocyte diameters were not differed significantly between BCB+ ($157.4{\pm}5.8{\mu}m$) and BCB+ ($149.0{\pm}31.0{\mu}m$) groups (p>0.05). However, the proportion of metaphase II oocytes in BCB+ group was significantly higher than BCB- group after IVM (p<0.05). GSH content of BCB+ group oocytes was significantly higher than that of BCB- group just after collection ($7.3{\pm}0.6$ vs. $4.8{\pm}0.6\;pmol/oocyte$, p<0.05), but not varied after IVM($13.1{\pm}0.9$ and $12.6{\pm}2.5\;pmol/oocytes$ for BCB+ and BCB- respectively; p>0.05). The proportion of blastocyst formation and total cell number in BCB+ group (23.5% and $105.5{\pm}28.6$) was significantly higher than that in BCB- (9.8% and $72.4{\pm}26.1$; p<0.05). The results indicate that BCB+ group oocytes may provide a cellular and functional basis for the greater developmental competence in Korean Native Cow (KNC) oocytes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권1호
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• pp.42-51
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• 2006

Schwann cell, one of important components of peripheral nervous system, interact with neurons to mutually support the growth and replication of embryonal nerves and to maintain the different functions of adult nerves. The Ara-C, known as an antimitotic agent, have been used to have high effectiveness in eliminating fibroblasts during Schwann cell culture period. This enrichment effect is also known to be cummulative with each successive pulse of Ara-C applied and is due to a progressive loss of fibroblasts. But the cytotoxicity by Ara-C is also cummulative and noticeable over the period. To determine the most effective application time and interval of Ara-C in the Schwann cell culture, we observed the Schwann cell purity and density with the Ara-C treatment in plain and three-dimensional culture from dorsal root ganglion of new born rat. By culturing dispersed dorsal root ganglia, we can repeatedly generate homogenous Schwann cells, and cellular morphology and cell count with mean percentages were evaluated in the plain culture dishes and in the immunostainings of S-100 and GFAP in the three-dimensional culture. The Ara-C treated cultures showed a higher Schwann cell percentage (31.0%${\pm}$8.09% in P4 group to 65.5%${\pm}$24.08% in P2 group), compared with that obtained in the abscence of Ara-C (17.6%${\pm}$6.03%) in the plain culture after 2 weeks. And in the three-dimensional culture, S-100 positive cells increased to 56.22%${\pm}$0.67% and GFAP positive cells to 66.46%${\pm}$1.83% in G2 group (p<0.05), higher yield than other groups with Ara-C application. Therefore, we concluded that the Ara-C treatment is effective for the proliferation of Schwann cells contrast to the fibroblasts in vitro culture, and the first application after 24 hours from cell harvesting and subsequent 2 pulse treatment (P2 group in plain culture and G2 group in three-dimensional culture) was more effective than other application protocols.

• 폴리머
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• 제37권2호
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• pp.141-147
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• 2013

Poly(lactide-co-glycolic acid)(PLGA)는 좋은 기계적 성질과 생분해성으로 약물전달시스템 또는 조직공학적으로 널리 이용되고 있으나 낮은 세포 부착률을 가지고 있어 피브린을 첨가하여 이를 보완하고자 하였다. 본 연구에서 사용된 지지체는 트롬빈과 피브리노겐, 그리고 세포을 혼합시킨 후 PLGA 지지체 위에 도포시켜 제조하였다. 세포의 부착 및 증식률을 측정하고자 PLGA/피브린 지지체에 늑연골 세포를 파종 후 1, 3일 및 7일 후 SEM과 MTT 분석을 통하여 측정하였으며, 세포외기질 형성에 미치는 피브린의 영향을 확인하고자 세포를 파종 후 누드마우스에 이식하여 GAG 및 콜라겐 합성의 효과를 확인하였다. 따라서 본 연구에서는 피브린이 혼합된 PLGA 지지체가 생체 내 외 환경에서 세포의 부착 및 증식에 미치는 영향을 확인하고자 연구를 진행하였다. 그 결과, PLGA/피브린 지지체가 기존의 PLGA 지지체와 비교하여 탁월한 세포 성장률을 나타내는 것으로 확인하였다.

• 한국동물학회지
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• 제31권1호
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• pp.49-55
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• 1988

SV80와 같은 SV40로 형질전환된 사람세포는 종양을 일으킬 수 있는 능력을 가지고 있으나 면역기구인 흉선이 없는 누드마우스에서는 거부반응을 일으켜 종양을 일으키지 않는다. 그러나, 예외적으로 WI18/VA-2세포는 누드마우스에서 종양을 일으키며 이에서 얻는 두클론중 NW18C11은 종양을 일으키나 NW18C12는 종양을 일으키지 않는다. 본 실험에서는 이들 두 클론의 차이점들을 조사하였다. 실험결과, NW18C11은 NW18C12보다 더 많은수의 SV40 sequence를 포함하고 있음을 southern blot방법을 통해 확인하였으며 또한 immunofluoresce와 immunoprecipitation방법을 사용하여 두 클론 모두 정상크기의 SV40유전자산물인 large T와 small t 단백질을 생성함을 확인하였다. 한편 두 클론내에 포함되어 있는 바이러스유전자가 비형질전환새포로 하여금 생체내에서 악성종양 형성능력을 획득하도록 형질전환시킬수 있는지 확인하기 위해 두 클론의 DNA를 추출하여 마우스 NIH3T3세포에 주입시켜 형질전환된 세포를 선별하였다. 이 세포들은 모두 large T단백질을 생성하였으며 누드마우스에서 종양을 일으켰다. 이들 결과로써 NW18C12세포의 형질전환능은 완전하며, 이 세포가 누드마우스에서 거부반응에 기인하는 것으로 생각된다.

• 한국식품저장유통학회지
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• 제12권1호
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• pp.8-16
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• 2005

본 연구에서는 김치의 숙도를 조절하여 선도유지기간을 연장할 목적으로 천연항균소재로서 항균작용 및 항진균작용이 탁월한 식물성 천연항균소재(Botanical Antimicrobial Agent-Citrus fruits : BAAC)를 이용하여 김치의 변패에 관여하는 미생물들에 대한 생육억제효과를 관찰하였다. 김치의 산패에 관여하는 Lactobacillus plantarum, Klebsiella pneumonia, Pichia membranaefaciences 등에 대하여 뚜렷한 BAAC의 항균력을 확인할 수 있었으며, 항균력은 BAAC의 농도에 비례하여 증대하였다. $\beta-galactosidase$활성은 BAAC 처리 미생물 세포의 경우, 무처리구인 대조구 세포보다 훨씬 높게 나타나 BAAC처리에 의하여 미생물 세포막의 기능성이 크게 떨어짐을 확인할 수 있었으며, 전자현미경 촬영 사진의 결과 분석을 통하여 BAAC를 처리한 미생물 세포는 세포막 및 세포벽 기능이 파괴되어 세포내용물이 균체외부로 유출되어 사멸하는 미생물 균수가 크게 증가하였다. 발효김치 재료를 BAAC에 침지 또는 분무등의 전처리 과정을 거친 후, BAAC처리농도 및 저장기간별로 미생물학적, 화학분석적 및 관능검사 결과치를 중심으로 숙성된 김치제품의 품질변화를 검토하였다. 김치 숙성중 pH변화는 BAAC를 첨가한 처리구의 경우, 첨가량이 증가할수록 대조구에 비하여 pH저하가 억제되는 것으로 나타났으며, 산도의 증가도 같은 경향으로 억제되었다. 김치 숙성중 대조구의 경우, 숙성이 진행됨에 따라 미생물수가 급격히 증가한 반면, BAAC처리 농도가 증가할수록 미생물의 성장이 억제되었다. 숙성기간이 경과할수록 BAAC를 첨가한 시험구는 대조구에 비하여 vitamin C함량은 완만하게 감소하는 경향을 보였다. 관능검사결과 $0.01\%$이하의 BAAC를 첨가하여 김치를 제조할 경우, 대조구와 향미 및 색도면에서 손색이 없는 김치생산이 가능할 수 있음을 확인할 수 있었다.

• Molecules and Cells
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• 제38권4호
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• pp.373-379
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• 2015

Pyruvate kinase M2 isoform (PKM2), a rate-limiting enzyme in the final step of glycolysis, is known to be associated with the metabolic rewiring of cancer cells, and considered an important cancer therapeutic target. Herein, we report a novel PKM2 activator, PA-12, which was identified via the molecular docking-based virtual screening. We demonstrate that PA-12 stimulates the pyruvate kinase activity of recombinant PKM2 in vitro, with a half-maximal activity concentration of $4.92{\mu}M$, and effectively suppresses both anchorage-dependent and -independent growth of lung cancer cells in non-essential amino acid-depleted medium. In addition, PA-12 blocked the nuclear translocalization of PKM2 in lung cancer cells, resulting in the inhibition of hypoxia response element (HRE)-mediated reporter activity as well as hypoxia-inducible factor 1 (HIF-1) target gene expression, eventually leading to the suppression of cell viability under hypoxia. We also verified that the effects of PA-12 were dependent on PKM2 expression in cancer cells, demonstrating the specificity of PA-12 for PKM2 protein. Taken together, our data suggest that PA-12 is a novel and potent PKM2 activator that has therapeutic implications for lung cancer.

• Molecules and Cells
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• 제38권11호
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• pp.991-997
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• 2015

Tristetraprolin (TTP) is an AU-rich elements (AREs)-binding protein, which regulates the decay of ARE-scontaining mRNAs such as proto-oncogenes, anti-apoptotic genes and immune regulatory genes. Despite the low expression of TTP in various human cancers, the mechanism involving suppressed expression of TTP is not fully understood. Here, we demonstrate that Resveratrol (3,5,4'-trihydroxystilbene, Res), a naturally occurring compound, induces glioma cell apoptosis through activation of tristetraprolin (TTP). Res increased TTP expression in U87MG human glioma cells. Res-induced TTP destabilized the urokinase plasminogen activator and urokinase plasminogen activator receptor mRNAs by binding to the ARE regions containing the 3' untranslated regions of their mRNAs. Furthermore, TTP induced by Res suppressed cell growth and induced apoptosis in the human glioma cells. Because of its regulation of TTP expression, these findings suggest that the bioactive dietary compound Res can be used as a novel anti-cancer agent for the treatment of human malignant gliomas.

• Molecules and Cells
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• 제38권11호
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• pp.966-974
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• 2015

Despite the presence of toll like receptor (TLR) expression in conventional $TCR{\alpha}{\beta}$ T cells, the direct role of TLR signaling via myeloid differentiation factor 88 (MyD88) within T lymphocytes on graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect after allogeneic stem cell transplantation (allo-SCT) remains unknown. In the allo-SCT model of C57BL/6 ($H-2^b$) ${\rightarrow}$ B6D2F1 ($H-2^{b/d}$), recipients received transplants of wild type (WT) T-cell-depleted (TCD) bone marrow (BM) and splenic T cells from either WT or MyD88 deficient (MyD88KO) donors. Host-type ($H-2^d$) P815 mastocytoma or L1210 leukemia cells were injected either subcutaneously or intravenously to generate a GVHD/GVL model. Allogeneic recipients of MyD88KO T cells demonstrated a greater tumor growth without attenuation of GVHD severity. Moreover, GVHD-induced GVL effect, caused by increasing the conditioning intensity was also not observed in the recipients of MyD88KO T cells. In vitro, the absence of MyD88 in T cells resulted in defective cytolytic activity to tumor targets with reduced ability to produce IFN-${\gamma}$ or granzyme B, which are known to critical for the GVL effect. However, donor T cell expansion with effector and memory T-cell differentiation were more enhanced in GVHD hosts of MyD88KO T cells. Recipients of MyD88KO T cells experienced greater expansion of Foxp3- and IL4-expressing T cells with reduced INF-${\gamma}$ producing T cells in the spleen and tumor-draining lymph nodes early after transplantation. Taken together, these results highlight a differential role for MyD88 deficiency on donor T-cells, with decreased GVL effect without attenuation of the GVHD severity after experimental allo-SCT.

• Molecules and Cells
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• 제43권7호
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• pp.619-631
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• 2020

In this study, we describe a novel function of TNNC1 (Troponin C1, Slow Skeletal and Cardiac Type), a component of actin-bound troponin, as a tumor suppressor of lung adenocarcinoma (LUAD). First, the expression of TNNC1 was strongly down-regulated in cancer tissues compared to matched normal lung tissues, and down-regulation of TNNC1 was shown to be strongly correlated with increased mortality among LUAD patients. Interestingly, TNNC1 expression was enhanced by suppression of KRAS, and ectopic expression of TNNC1 in turn inhibited KRAS^G12D-mediated anchorage independent growth of NIH3T3 cells. Consistently, activation of KRAS pathway in LUAD patients was shown to be strongly correlated with down-regulation of TNNC1. In addition, ectopic expression of TNNC1 inhibited colony formation of multiple LUAD cell lines and induced DNA damage, cell cycle arrest and ultimately apoptosis. We further examined potential correlations between expression levels of TNNC1 and various clinical parameters and found that low-level expression is significantly associated with invasiveness of the tumor. Indeed, RNA interference-mediated down-regulation of TNNC1 led to significant enhancement of invasiveness in vitro. Collectively, our data indicate that TNNC1 has a novel function as a tumor suppressor and is targeted for down-regulation by KRAS pathway during the carcinogenesis of LUAD.