• Molecules and Cells
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• 제26권2호
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• pp.107-112
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• 2008

Invasion mechanisms of pathogens and counteracting defense mechanisms of plants are highly diverse and perpetually evolving. While most classical studies of plant defense have focused only on defense-specific factor-mediated responses, recent work is beginning to shed light on the involvement of non-stress signal components, especially growth and developmental processes. This shift in focus links plant resistance more closely with growth and development. In this review, we summarize our current understanding of how pathogens manipulate host developmental processes and, conversely, of how plants deploy their developmental processes for self-protection. We conclude by introducing our recent work on UNI, a novel R protein in Arabidopsis which mediates cross-talk between developmental processes and defense responses.

• Molecules and Cells
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• 제26권5호
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• pp.514-516
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• 2008

The cancer stem cell hypothesis posits that tumor growth is driven by a rare subpopulation of cells, designated cancer stem cells (CSC). Studies supporting this theory are based in large part on xenotransplantation experiments wherein human cancer cells are grown in immunocompromised mice and only CSC, often constituting less than 1% of the malignancy, generate tumors. Herein, we show that all colonies derived from randomly chosen single cells in mouse lung and breast cancer cell lines form tumors following allografting histocompatible mice. Our study suggests that the majority of malignant cells rather than CSC can sustain tumors and that the cancer stem cell theory must be reevaluated.

• 한국해양바이오학회지
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• 제2권3호
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• pp.198-200
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• 2007

Cultivation of a $Q_{10}$-producing photosynthetic bacterium, Rhodobacter sphaeroids, was carried out in a 1-L flask to characterize its cellular growth reaction. The result of experiment showed that dissolve oxygen in the broth was depleted within 7 h. ORP decreased with decrease of DO, and recovered somewhat with increase of pH. The growth of R. spahaeroids reached at late-log phase in 140 h of reaction. The final pH and dry-cell weight were 7.62 and 2.2 mg/mL, respectively. The $Q_{10}$ content in the final broth was 2.35 mg/g dry cell weight, which was higher than that obtained in tube culture.

• ALGAE
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• 제29권4호
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• pp.311-319
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• 2014

The biocide sodium hypochlorite (NaOCl) is widely used for controlling algal growth, and this application can be extended to marine environments as well. This study evaluates the biocidal efficiency and cellular toxicity of NaOCl on the harmful dinoflagellate Cochlodinium polykrikoides, with emphasis on pigment production and antioxidant enzyme activity. The test organism showed dose-dependent decrease in growth rate on exposure to NaOCl, and the 72 h $EC_{50}$ was measured to be $0.584mg\;L^{-1}$. NaOCl significantly decreased pigment levels and chlorophyll autofluorescence intensity, indicating possible detrimental effects on the photosystem of C. polykrikoides. Moreover, it significantly increased the activities of antioxidant enzymes, suggesting the production of reactive oxygen species in the cells. These data indicate that NaOCl exerted deleterious effects on the photosynthetic machinery and induced oxidative damage in the dinoflagellate and this biocide could be effectively used for the control of algal blooms.

• 한국발생생물학회지:발생과생식
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• 제15권2호
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• pp.173-178
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• 2011

The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA) is a potent monoaminergic neurotoxin with the potential to cause serotonergic neurotoxicity, but has become a popular recreational drug. Little has been known about the cellular effects induced by MDMA. This report shows that MDMA inhibits neuronal cell growth and differentiation. MDMA suppressed neuronal cell growth. The results of quantitative real-time PCR analysis showed that Egr-1 expression is elevated in mouse embryo and neuroblastoma cells after MDMA treatment. Transiently transfected Egr-1 interfered with the neuronal differentiation of neuroblastoma cells such as SH-SY5Y and PC12 cells. These findings provide evidence that the abuse of MDMA during pregnancy may impair neuronal development via an induction of Egr-1 over-expression.

• 한국치위생학회지
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• 제1권1호
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• pp.101-109
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• 2001

This study was conducted to investigate the effect of natural resources against growth of oral bacteria. The CHJ-5 strain was isolated from oral cavity of dental patients. Similarity index values of oral bacterium CHJ-5 was 0.876 to E. faecalis by cellular fatty acid analysis(Analytical Services Inc., USA). As a result of investigation about the growth inhibition of 32 kinds of natural resources on E. faecalis CHJ-5. This strain was inhibited by Schizamdrae fructus, Coptidis rhizoma and Caryophylli flos. Minimal inhibitory concentrations of Schizamdrae fructus, Coptidis rhizoma and Caryophylli flos were 0.1%, 02% and 0.1% on E. faecalis CHJ-5, respectively.

• Journal of Microbiology and Biotechnology
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• 제11권2호
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• pp.310-316
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• 2001

Poly-3-hydroxybutyrate (PHB) synthase catalyzed the last enzymic step to synthesize the intracellular PHB of Rhodobacter sphaeroides. No PHB was detected when the phbC coding for PhB synthase was interrupted, and its expression was regulated at the level of transcription. The cellular PHB content increased about four- to six-fold during the growth transition from the exponential to the early stationary phase under both aerobic and photoheterotrophic conditions. The PHB content during the aerobic growth seemed to be determined by the PhB synthase activity. However, the PHB synthase activity of photoheterotrophically grown cells did not correlate with the PhB content, suggesting a photoheterotrophic regulation different from the aerobic control. Thus, the PHB content of R. sphaeroides was regulated at the transcription level only under aerobic conditions.

• Journal of Microbiology and Biotechnology
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• 제24권9호
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• pp.1291-1299
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• 2014

Recently, multifunctional nanomaterials have been developed as nanotherapeutic agents for cellular imaging and targeted cancer treatment because of their ease of synthesis and low cytotoxicity. In this study, we developed a multifunctional, two-component nanorod consisting of gold (Au) and nickel (Ni) blocks that enables dual-fluorescence imaging and the targeted delivery of small interfering RNA (siRNA) to improve cancer treatment. Fluorescein isothiocyanate-labeled luteinizing hormone-releasing hormone (LHRH) peptides were attached to the surface of a Ni block via a histidine-tagged LHRH interaction to specifically bind to a breast cancer cell line, MCF-7. The Au block was modified with TAMRA-labeled thiolated siRNA in order to knock down the vascular endothelial growth factor protein to inhibit cancer growth. These two-component nanorods actively targeted and internalized into MCF-7 cells to induce apoptosis through RNA interference. This study demonstrates the feasibility of using two-component nanorods as a potential theranostic in breast cancer treatment, with capabilities in dual imaging and targeted gene delivery.

• Journal of Microbiology and Biotechnology
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• 제1권4호
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• pp.288-292
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• 1991

The aim of the current study is to evaluate the effects of medium compositions on the production of protease inhibitor in Streptomyces sp. SMF13. The production of protease inhibitor was counter-currently linked to extra-cellular protease, which were regulated by the culture conditions. Nitrogen source was the most critical ingredient affecting the production of protease inhibitor and protease. Carbon source was an important factor to determine the culture pH which affected very clearly the formation of protease and protease inhibitor. Inorganic phosphate inhibited the protease inhibitor production which was linked to the cell growth rate, although the optimal conditions for the production of protease inhibitor were not favouring to the cell growth.

• 한국세라믹학회지
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• 제36권6호
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• pp.640-645
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• 1999

Recently rapid progress of electronic and telecommunication technology requires the development of new piezoelectric materials and cellular communication is more and more used in various fields. Langasite(La3Ga5SiO14) is suitable for new piezoelectric properties. Langastie can be applied as communication devices due to intermediate piezoelectric properties which are similar to those of quartz and LiTaO3 in its acoustic characteristics. So in this study Langastie(La3Ga5SiO14) single crystal with 47 mm in diameter and 25mm in length were sucessfully grown by using self-designed Czochralski system. In addition optimum growth conditions for the piezoelectric applications throughout estimation of crystal quality and frequency characteristics were investigated.