• Development and Reproduction
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• v.16 no.4
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• pp.329-338
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• 2012

The proliferation of embryonic cells or adult stem cells in tissue is critically regulated during development and repair. How limited the proliferation of cells, so far, is not much explored. Cell-cell contact proliferation inhibition is known as a crucial mechanism regulating cell proliferation in vitro and in vivo. In this study we examined the characters of mouse subcutaneous adipose derived stem cells (msADSC) whether they lost or get contact inhibition during in vitro culture. The characters of msADSC growth after confluence were analyzed using confocal microscope and the expression profiles of contact inhibition related genes were analyzed according to the morphological changes using real-time PCR method. msADSC showed overlapping growth between them but not after passage 14. The cell shapes were also changed after passage 14. The expression profiles of genes which are involved in contact inhibition were modified in the msADSC after passage 14. The differentiation ability of msADSCs to adipocyte, chondrocyte and osteocyte was not changed by such changes of gene expression profiles. Based on these results, it is revealed that smADSC were characterized by getting of strong cell-cell contact inhibition after passage 14 but the proliferation and developmental ability were not blocked by the change of cell-cell contact proliferation inhibition. These finding will help to understand the growth of adipose tissue, although further studies are needed to evaluate the physiological meaning of the cell-cell contact proliferation inhibition during in vitro culture of msADSC.

• YAKHAK HOEJI
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• v.48 no.1
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• pp.27-29
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• 2004

The essential oil fractions from six plant parts including leaf of Zanthoxylum piperitum and flower of Lindera obtusiloba have revealed to possess resistance inhibitory activity on antibiotic resistant Staphylococcus aureus SA2 when combined with ohloramphenicol (Cm). The combination of Cm and essential oil mixtures showed potent resistance inhibition in the level of 10∼20 $\mu\textrm{g}$/ml.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.244.1-244.1
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• 2002

Cyclooxygenase-2 ( COX-2 ) is an inducible enzyme which produces prostanoids by various stimuli. Overexpression of COX-2 in many tumor types indicates its association with tumor progression, which has been a promising target for chemoprevention and chemomodulation. We studied conc- and time-dependency of COX-2 inhibition, growth inhibition, and cell cycle arrest induced by celecoxib, a selective COX-2 inhibitor, in human non-small cell lung cancer (NSCLC) A549 cells. (omitted)

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.3
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• pp.193-201
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• 2006

Squamous cell carcinoma(SCC) of head and neck(SCCHN) is the sixth most common human malignant tumor. However, despite advances in prevention and treatment of SCC, the five-year survival rates for patients remain still low. To improve the outcome for patients with SCCHN, novel treatment strategies are needed. Overexpression of the epidermal growth factor(EGF) and activation of its receptor(EGFR) are associated with progressive growth of SCCHN. Vascular endothelial growth factor(VEGF) signaling molecules are related with neoangiogenesis and vascular metastasis of SCC. In this study, we determined the therapeutic effect of AEE788(Novartis Pharma AG, Basel, Switzerland), which is a dual inhibitor of EGFR/ErbB2 and VEGFR tyrosine kinases, on human oral SCC. At first, we screened the expression of EGFR, c-ErbB2(HER-2) and VEGFR-2 in a series of human oral SCC cell lines. And then we evaluated the effects of AEE788 on the phosphorylation of EGFR and VEGFR-2 in a oral SCC cell line expressing EGFR/HER-2 and VEGFR-2. We also evaluated the effects of AEE788 alone, or with paclitaxel(Taxol) on the oral SCC cell growth and apoptosis. As a result, all oral SCC cells expressed EGFR and VEGFR-2. Treatment of oral SCC cells with AEE788 led to dose-dependent inhibition of EGFR and VEGFR-2 phosphorylation, growth inhibition, and induction of apoptosis. Moreover, AEE788 sensitizes the cells to paclitaxel-mediated toxicity and apoptosis. These data mean EGFR and VEGFR-2 can be reliable targets for molecular therapy of oral SCC, and therefore warrant clinical use of EGFR/VEGFR inhibition in the treatment of patients with recurrent or metastatic oral SCC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.8
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• pp.1233-1238
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• 2003

The growth inhibitory effects of chloride salts and organic acid salts against six food-borne microorganisms (Bacillus cereus ATCC 11778, Escherichia coli O157:H7 ATCC 43894, Listeria monocytogenes ATCC 19111, Salmonella Typhimurium ATCC 14028, Staphylococcus aureus ATCC 25923, Vibrio parahaemolyticus ATCC 17802) were determined using Bioscreen C in broth medium. The growth inhibitory concentrations of sodium chloride and potassium chloride on B. cereus were 7 and 9%, respectively. E. coli O157:H7 and S. aureus were inhibited by treatment of 3% calcium chloride. Magnesium chloride showed growth inhibitory effect on B. cereus, S. Typhimurium, and S. aureus at 5%. The order of growth inhibition effects by organic acid salts was calcium propionate>calcium acetate>calcium lactate. Calcium chloride (3%) with 0.01% lactic acid showed strong inhibition on the growth of S. Typhimurium and exhibited stronger growth inhibition than calcium chloride alone (5%). We concluded that calcium chloride and calcium propionate had strong growth inhibitory activities and that calcium chloride and sodium chloride in combination with lactic acid had stronger inhibitory activities than that of chloride salts alone.

• Journal of Microbiology and Biotechnology
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• v.20 no.8
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• pp.1240-1242
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• 2010

We attempted to identify the compound responsible for the growth inhibition of Microcystis aeruginosa occurring when a culture broth of Bacillus subtilis C1 was added to the medium. The active compound was purified from B. subtilis C1 culture broth by adsorption chromatography and HPLC, and was identified as a type of glycolipid based on $^1H$ NMR and MS analyses. The purified active compound completely inhibited the growth of M. aeruginosa at a concentration of 10 ${\mu}g/ml$. This is the first report of a glycolipid produced by a Bacillus strain that has potential as an agent for the selective control of bloom-forming M. aeruginosa.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.183-188
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• 1997

Antimicrobial activity of various extracts of Xanthium strumarium L. was tested against 25 strains of bacteria, yeast and fungus. The crude ethylacetate extract exhibited strong growth inhibition to the tested strains with the exception of partial Gram-negative bacteria. The property of antimicrobial compound was very stable under heat treatment at $120^{\circ}C$, but it was unstable in acid (pH 3.0) and alkali (pH 10.0) treatment. The antimicrobial compounds were purified by boiling water extraction, ethylacetate extraction, charcoal column chromatography, silica gel column chro- matography and reverse phase HPLC. The purified compound A and B were detected in a single peak (each above 98% purity) through the HPLC analysis. The compound A and B showed a strong growth inhibition against Gram-negative and positive bacteria in the agar diffusion method. When tested by the FDA method using the esterase, compound A mainly inhibited the growth of bacteria and compound B showed the growth inhibition of both bacteria and yeasts.

• East Asian mathematical journal
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• v.36 no.1
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• pp.81-90
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• 2020

Many compartment models assume a kinetically homogeneous amount of materials that have well-stirred compartments. However, based on observations from such processes, they have been heuristically fitted by exponential or gamma distributions even though biological media are inhomogeneous in real environments. Fractional differential equations using a specific kernel in Pharmacokinetic/Pharmacodynamic (PKPD) model are recently introduced to account for abnormal drug disposition. We discuss a tumor growth inhibition (TGI) model using fractional-order derivative from it. This represents a tumor growth delay by cytotoxic agents and additionally show variations in the equilibrium points by the change of fractional order. The result indicates that the equilibrium depends on the tumor size as well as a change of the fractional order. We find that the smaller the fractional order, the smaller the equilibrium value. However, a difference of them is the number of concavities and this indicates that TGI over time profile for fitting or prediction should be determined properly either fractional order or tumor sizes according to the number of concavities shown in experimental data.

• Applied Chemistry for Engineering
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• v.19 no.3
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• pp.277-286
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• 2008

This paper deals with the theoretical derivation of the modified Haldane model of the substrate inhibition in the microbial growth processes. Based on the biological concepts of substrate-receptor complex working mechanisms, a new microbial kinetics of N-fold multiplex substrate inhibition and its generalization has been considered theoretically, which is natural expansion of the simple substrate inhibition mechanism in the enzyme reaction. As a result, the modified Haldane model of the substrate inhibition turns out to be a well-designed four-parameter kinetic model with a biological constant of the total substrate inhibition concentration.

• The Journal of Korean Medicine
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• v.27 no.4
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• pp.162-173
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• 2006

The water-extracts of Scutellaria barbata Don (SBDE) were isolated from Chinese medicinal plant sources. The extracts showed strong growth-inhibitory activity and cancer chemopreventive activity on the growth and DNA incorporation of MG63 human osteosarcoma and K562 human leukemia cell lines. The growth of human cancer cells was inhibited in the presence of the extracts (20, 50 and 100 ${\mu}$g/ml), and the effects were concentration-dependent and incubation time-dependent up to 8 days. When 50 ${\mu}$g/ml of the extracts was added to the media of MG63 and K562, cell growth after 8 days or 6 days of incubation was retarded by 93.2 to 97.3% of the control group. Morphological changes of MG63 and K562 cell lines were observed. As the concentration of the extracts increased up to 50 ${\mu}$g/ml, degree of cell aggregation decreased. Moreover, the DNA incorporation of the cells which were labeled with [3H] thymidine was significantly reduced after 3 days of incubation at $37^{\circ}C$ with the extract. Therefore, it is suggested that the extract is highly effective on inhibition of cancer cell growth. The extract also inhibited gene expression of IGF-II in transcriptional level. Since IGF-II works as a mitogenic effector on MG63 and K562 cell lines, these results suggest that the growth inhibition is in part mediated through the inhibition of IGF-II gene expression.