• Journal of the Korean Chemical Society
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• v.50 no.3
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• pp.216-223
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• 2006

To increase the stability of liposomes in blood circulation, surface modification of liposomes by incorporating a lipid-polymer derivative in the lipid bilayer or conjugating a hydrophilic polymer to the liposomal surface has been developed. In this study, the comblike copolymer, poly(HEMA-co-HPOEM), having multiple polyethyleneoxide side chains was prepared by free radical polymerization of hydroxyethylmethacrylate (HEMA) and hydroxypolyoxyethylenemethacrylate (HPOEM) as vinyl monomers. Poly(HEMA-co-HPOEM) was conjugated to the liposomal surface and the characteristics of the modified liposomes in serum were investigated. Conjugation of poly(HEMA-co-HPOEM) to liposomes increased the particle size of the liposomes by 30 nm and decreased the absolute value of zeta potential of the liposomes by shielding the negative charge of liposomal surface. Loading efficiency of model drug, doxorubicin, in liposomes was about 90% and the efficiency was not affected by conjugation of poly(HEMA-co-HPOEM) to liposomes. The particle size of poly(HEMA-co-HPOEM)-conjugated liposomes in serum did not changed and the protein adsorption was lower than that of control liposomes or liposomes containing polyethyleneoxide-lipid derivative (PEG-liposomes). These results suggest that poly(HEMA-co-HPOEM) is efficient for the stabilization of liposomes in blood circulation.

• Korean Journal of Food Science and Technology
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• v.52 no.1
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• pp.26-30
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• 2020

This study was undertaken to determine the characteristics of xanthoangelol, the major chalcone constituent derived from the extracts of different parts of Lespedeza bicolor. Xanthoangelol was isolated from the root extract using column chromatography and used as a standard for quantitative analysis. The structure of the isolated compound was established based on spectroscopic evidence. The HPLC-DAD method was validated for specificity, linearity, precision, accuracy, limit of detection, and limit of quantitation. The calibration curve of xanthoangelol had significant linearity (R²>0.9999). Limit of detection and limit of quantitation 0.018 and 0.059 ㎍/mL, respectively. The relative standard deviation values of precision test, and intra- and inter-day tests were less than 0.22 and 0.40%, respectively. In the recovery test, the accuracy ranged from 98.98-102.78% with RSD values less than 0.13%. The method validation parameters indicate the applicability of the HPLC method for quality control of food or drug formulations containing L. bicolor.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.5
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• pp.687-692
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• 2012

Schizandra chinensis extract has been known to possess a variety of efficacy including antitumor. However, it remains unclear how schizandrin, which is a major biological active ingredient of Schizandra chinensis, exerts antitumor effect. This study was designed to investigate the mechanism by which schizandrin inhibits tumor growth and metastasis. In in vivo test using tumor model mice injected with B16BL6 cell line, mice treated with 10 and 100 ${\mu}g/ml$ schizandrin showed a significant inhibition by $73.79{\pm}6.43%$ and $90.46{\pm}1.72%$, respectively, compared with positive tumor controls. Schizandrin did not exert a significant toxicity for the normal cells (HUVECs) and tumor cell lines (A549, B16BL6, Du145, Huh7). Treatment with schizandrin at 10 and 100 ${\mu}g$/head significantly inhibited the tumor-induced angiogenesis by $68.04{\pm}32.21%$ and $103.8{\pm}34.99%$ compared with the positive control group, respectively. Using in vivo lung metastasis model, tumor metastasis assay revealed that 10 and 100 ${\mu}g$/head schizandrin significantly decreased the metastatic lung tumor by $37.51{\pm}8.15%$ and $75.53{\pm}4.38%$ compared with positive controls, respectively. On the other hand, schizandrin did not affect the adherence of B16BL6 cell line to extracellular matrix protein. These results demonstrate that schizandrin exerts inhibitory effect on tumor growth and metastasis by inhibiting angiogenesis. This study thus suggest that schizandrin may be a candidate molecule target for cancer drug development.

• Radiation Oncology Journal
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• v.4 no.1
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• pp.1-13
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• 1986

In order to clarify the effect of radiation on the mouse jejunal crypt cells by combined administration of administration and radiation and also to evaluate the enhancing effect of adriamycin, the authors performed this study by delivering single irradiation of 1,000 to 1,600 rad to the whole abdomen of mice by cobalt-60 teletherapy unit. In combination with adriyamycin treatment groups, the drug was administered as single dose of 10 mg/kg either 2 hours before or 4 hours after graded single dose,900 to 1,400 rad, of irradiation. The authors studied the quantitative changes of intestinal crypt cells by microcolony survival assay technique and the morphological changes of small intestinal villi by scanning electron microscope in mice following to combined therapy with adriamycin and irradiation, The average number of jejunal crypts per circumference was $130{\pm}16$ in control group. The mean lethal dose(Do) of each irradiation alone and combined therapy groups 2 hours before and 4 hours after irradiation, were 160, 170, and 170 rad in cell survival curves, respectively. The dose effect factor(DEF) of adriamycin in each groups of pre-irradiation and post-irradiation were 1.19 and 1.26, respectively. The conical shaped villi were noted on 1,200 rad in irradiation alone group and 1,000 rad in combined groups. For the proper clinical application we must be careful of the radiation injury to small bowel when the anticancer chemotherapy and radiation therapy to the abdomen and pelvic area are used as combined therapeutic modality.

• Korean Journal of Veterinary Service
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• v.22 no.3
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• pp.221-237
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• 1999

To investigate the specificity of rapid slide agglutination test for pullorum-gallinarum diseases and to obtain a basic data for avian salmonellosis control, salmonella isolation was peformed for the layer chickens positively reacted in pullonlm-typhoid agglutination test. The biochemical, serological and antimicrobial properties of the isolates were examined. The results obtained through this study were summarized as follows; 1. Of 2,384 chickens tested by the agglutination test, 606 chickens (25.4%) were positive reactors. 154 of 606 reactors and 49 of the non-reacting chickens were investigated for salmonella isolation, resulting in isolation of 68 strains of salmonellae from 27 chickens. 2. By organs, the isolation frequency from liver, cecum, spleen, ovary and gall bladder showed 8.9% (18 strains), 8.9% (18 strains), 7.4% (15 strains), 4.4% (9 strains) and 3.9% (8 strains), respectively. 3. By culture medium the combination of selenite broth and MacConkey agar revealed the highest isolation rate and the enrichment culture by delayed secondary enrichment culture method was found the most effective for salmonella isolation. 4. The serotypes of 68 salmonella isolates were identified as 3 strains of S pullorum, 24 strains of S gallinarum, 15 strains of S typhimurium, 8 strains of S enteritidis, 7 strains of S paratyphi A, 5 strains of S typhimurium and 6 strains of the other salmonellae. 5. The serotypes of 8 salmonella strains isolated from 49 chickens non-reacting in pullorum-typhoid agglutination test were identified as 3 strains of S typhimurium and 5 strains of S infantis. 6. When 24 chickens of which 68 strains of salmonellae isolated were examined by microplate agglutination test, the average antibody titer for pullorum antigen was $2^{5.25}$. The chickens at antibody titer between $2^3$ and $2^5$ showed the higher frequency of isolation as compared with the chickens at the other titers. 7. When salmonella isolates were tested the antimicrobial drug sensitivity by disk diffusion method, S paratyphi A were highly sensitive by 100% to ATM and GM, S typhimurium, by 88% to AM, CIP, IMP and TN, S infantis, by 100% to AM, CRO, ENR and PIP, S enteritidis,by 100% to IMP and PIP, S pullorum, by 100% to ATM, CRO, ENR and PIP and S gallinarum, by 92% to CRO, CIP and PIP.

• Journal of Food Hygiene and Safety
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• v.19 no.4
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• pp.198-202
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• 2004

It was carried out to compare the relationship of EEC 4-plate test method and Charm II test method by HPLC. 46 only tetracyclines, 4 only sulfonamides, 4 sulfonamides+tetracyclines, one amphenicols+tetracyclines, and one amphenicols+sulfonarnides+tetracyclines, it was detected on 71 porks of EEC 4-plate positive or Charm II positive by HPLC. In case of sulfonamides and chloramphenicols, two test methods had related with each other, but had no relation in tetracyclines. Also, it was $10.5\%(6/57)$ tetracyclines, $81.8\%(9/11)$ chloramphenicols that were EEC 4 plate positive or Charm II positive, but not detectrd by HPLC. Consequently, EEC 4-plate test method and Charm II test method were suitable by screening test on antibiotics and sulfonamides etc.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.6
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• pp.741-755
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• 1999

As a material of metal-ceramic prosthesis, nickel as a form of Ni-Cr alloy has been used for many dental prostheses in many cases. However, several problems in use of the alloy have been revealed (ex : tissue stimulation, skin allergy, hypersensitivity, cytotoxicity and carcinogenecity). Little is known about nickel with respect to the relationship between Ni-prosthesis and gaining of Ni-resistance in oral microorganisms. The present study was undertaken to check wheather use of Ni-prosthesis leads to occurrence of Ni-resistant microorganisms. So this study may suggest the possible relationships between the oral microorganisms and nickel-resistance in oral environment. Bacteria were isolated from the gingival crevicular fluid on the pateints wearing Ni-Cr prosthesis. The isolated bacteria were tested for their Ni-resistance in nickel containing media at different concentration from 3mM to 110mM. E. coli HB101 was used as control. The Ni-resistant bacteria were isolated and biochemically identified. The Ni-resistant bacteria were tested several bio-chemical, molecular-biological tests. Performed tests were ; measuring the growth curve, antibiotic test, growth ability test in liquid media, isolation of the chromosome and plasmid, digestion of DNA by restriction enzyme, electrophoresis of chromosome and plasmid DNA, identification of Ni-resistant genes by the DNA hybridization. The results were as follows: 1) The bacteria isolated from gingival crevicular fluid on the patients wearing Ni-Cr alloy pros-thesis showed nickel-resistance. 2) The isolated microorganisms grew at nickel containing media of high concentrations (60mM-110mM). 3) Based on the biochemical tests, the isolated microorganisms were identified as Enterococcus faecalis(13 cases), Klebsiella pneumoniae(1 case) and Enterobacter gergeviae(1 case). 4) Enterococcus faecalis expressed not only nickel resistance but also the multi-drug resistance to several antibiotics ; chloramphenicol, kanamicin, streptomycin, lincomycin, clindamycin. However, all strain showed the sensitivity against the tetracycline. 5) DNA hybridization result suggest that there is no homology between the previousely known gene of nickel resistance in Klebsiella pneumoniae and chromosomal DNA of Enterococcus faecalis.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.909-914
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• 2012

Background: Gefitinib, a tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR), is used both as a single drug and concurrently with whole brain radiotherapy (WBRT) the standard treatment for brain metastases (BM), and is reported to be effective in a few small studies of patients with BM from non-small-cell lung cancer (NSCLC). However, no study has compared the two treatment modalities. This retrospective analysis was conducted to compare the efficacy of gefitinib alone with gefitinib plus concomitant WBRT in treatment of BM from NSCLC. Methods: We retrospectively reviewed 90 patients with BM from NSCLC who received gefitinib alone (250mg/day, gefitinib group) or with concomitant WBRT (40Gy/20f/4w, gefitinib-WBRT group) between September 2005 and September 2009 at Sun Yat-Sen University Cancer Center. Forty-five patients were in each group. Results: The objective response rate of BM was significantly higher in gefitinib-WBRT group (64.4%) compared with gefitinib group (26.7%, P<0.001). The disease control rate of BM was 71.1% in gefitinib-WBRT group and 42.2% in gefitinib group (P=0.006). The median time to progression of BM was 10.6 months in gefitinib-WBRT group and 6.57 months in gefitinib group (P<0.001). The median overall survival(OS) of gefitinib-WBRT and gefitinib alone group was 23.40 months and 14.83 months, respectively (HR, 0.432, P=0.002). Conclusion: Gefitinib plus concomitant WBRT had higher response rate of BM and significant improvement in OS compared with gefitinib alone in treatment of BM from NSCLC.

• Journal of Nutrition and Health
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• v.46 no.4
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• pp.315-323
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• 2013

This study was conducted in order to compare the biological activities of leaf and root water extracts of Smilax china L. (SC) by measuring the total polyphenol and flavonoid contents, anti-oxidant activity, inhibitory effect on ${\alpha}$-glucosidase, and anti-inflammatory gene expression. The total polyphenol and flavonoid contents of SC leaf (SCLE) and root (SCRE) water extracts were 127.93 mg GAE/g and 39.50 mg GAE/g and 41.99 mg QE/g and 1.25 mg QE/g, respectively. The anti-oxidative activities of SCLE and SCRE were measured using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity assay and reducing power assay. Both SCLE and SCRE scavenged radicals in a concentration-dependent manner, and SCLE showed stronger radical scavenging activity and reducing power than SCRE; however, both SCLE and SCRE exhibited lower activities than ascorbic acid. Compared to the anti-diabetic drug acarbose, which was used as a positive control, SCLE and SCRE exhibited low ${\alpha}$-glucosidase inhibition activities; nevertheless, the activity of SCLE was 3.7 fold higher than that of SCRE. Finally, SCLE caused significantly decreased expression of the LPS-induced cytokines, iNOS, and COX-2 mRNA in RAW264.7 cells, indicating anti-inflammatory activity. These results indicate that SCLE might be a potential candidate as an anti-oxidant, anti-diabetic, and anti-inflammatory agent.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10659-10663
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• 2015

Background: Rapamycin is an effective anti-angiogenic drug. However, the mode of its action remains unclear. Therefore, in this study, we aimed to elucidate the antitumor mechanism of rapamycin, hypothetically via apoptotic promotion, using MCF-7 breast cancer cells. Materials and Methods: MCF-7 cells were plated at a density of $1{\times}10^5$ cells/well in 6-well plates. After 24h, cells were treated with a series of concentrations of rapamycin while only adding DMEM medium with PEG for the control regiment and grown at $37^{\circ}C$, 5% $CO_2$ and 95% air for 72h. Trypan blue was used to determine the cell viability and proliferation. Untreated and rapamycin-treated MCF-7 cells were also examined for morphological changes with an inverted-phase contrast microscope. Alteration in cell morphology was ascertained, along with a stage in the cell cycle and proliferation. In addition, cytotoxicity testing was performed using normal mouse breast mammary pads. Results: Our results clearly showed that rapamycin exhibited inhibitory activity on MCF-7 cell lines. The $IC_{50}$ value of rapamycin on the MCF-7 cells was determined as $0.4{\mu}g/ml$ (p<0.05). Direct observation by inverted microscopy demonstrated that the MCF-7 cells treated with rapamycin showed characteristic features of apoptosis including cell shrinkage, vascularization and autophagy. Cells underwent early apoptosis up to 24% after 72h. Analysis of the cell cycle showed an increase in the G0G1 phase cell population and a corresponding decrease in the S and G2M phase populations, from 81.5% to 91.3% and 17.3% to 7.9%, respectively. Conclusions: This study demonstrated that rapamycin may potentially act as an anti-cancer agent via the inhibition of growth with some morphological changes of the MCF-7 cancer cells, arrest cell cycle progression at G0/G1 phase and induction of apoptosis in late stage of apoptosis. Further studies are needed to further characterize the mode of action of rapamycin as an anti-cancer agent.