• Biomolecules & Therapeutics
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• v.17 no.4
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• pp.370-378
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• 2009

N-myc downstream-regulated gene 2 (NDRG2) has recently been found to be a tumor suppressor gene. Although it has been reported that NDRG2 expression in breast cancer cells decreases cell proliferation by inhibiting STAT3 activation via SOCS1 induction, the molecular mechanism of chemotherapeutic agent-induced apoptosis is not well known. To elucidate the effect of NDRG2 on the apoptotic pathway induced by doxorubicin, we established stable cell lines expressing NDRG2 and investigated the effect of NDRG2 expression on the doxorubicin-induced apoptosis. While STAT3 activation was remarkably inhibited by NDRG2 overexpression, the expression level of p21 was increased by NDRG2 expression. We confirmed that NDRG2-expressing cells treated with doxorubicin suppressed STAT3 activation and upregulated p21 expression. NDRG2 expression considerably enhanced TUNEL positive apoptotic cells, poly-ADP ribose polymerase (PARP) cleavage, release of cytochrome c to cytosol, and caspase-3 activity in doxorubicin-induced apoptosis. Bid expression in a resting state and after treatment with doxorubicin increased in MDA-MB-231-NDRG2 cells compared to MDA-MB-231-mock cells. Meanwhile, Bcl-$x_L$ expression decreased in MDA-MB-231-NDRG2 cells compared to MDA-MB-231-mock cells in a resting state and in doxorubicin-treated cells. Collectively, these data suggest that suppression of STAT3 activation by NDRG2 influences the sensitivity to doxorubicin-induced apoptosis of breast cancer cells and this may provide a potential therapeutic benefit to overcome the resistance against doxorubicin in breast cancer.

• Journal of Chest Surgery
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• v.22 no.5
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• pp.713-723
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• 1989

In order to assess the correlation of the myocardial damage and the duration of cardiopulmonary bypass, measurement of creatine kinase [CK], lactate dehydrogenase [LDH], asparatate aminotransferase [AST], and MB band of CK [CK-MB] were carried out on the first, third, fifth, seventh, and ninth day in 44 patients following open heart surgery [POD 1,3,5,7,9]. And the patients were divided into three groups according to the duration of aortic cross clamp time [ACT]: Group I [ACT< 60 minutes. n=19], Group II [60 minutes < ACT< 90 minutes, n=7] and Group III[90 minutes > ACT, n=18]. 1. The leakage of CK in total patients increased to the highest level at POD 1, with rapid decrease and recovery at POD 7. The leakage of CK in Group III were greater than in Group I from POD 1 to POD 3 [P < 0.01]. The recovery time of CK level was shorter in Group I [POD 3] than in Group II and III [POD 7]. 2. The serum levels of LDH in total patients increased to the highest level at POD 1, with slow recovery until POD 9. The levels of LDH in Group III were higher than in Group I until POD 9 [P < 0.005]. The levels of LDH in Group I and II recovered but not in Group III. 3. The serum levels of AST in total patients increased to the highest level at POD 1, with rapid decrease and recovery at POD 7. The levels of AST in Group III were greater than in Group I from POD 1 to POD 5 [P < 0.05]. The recovery time of AST level was shorter in Group I and II [POD 5] than in Group III [POD 7]. 4. The positive cases for CK-MB in 36 patients were 22 [61.1 %] as a whole, 5[41.6%] in Group I, 4[57.1 %] in Group II, 13[76.4 %] in Group III at POD 1, and a case in each group at POD 3, and only a case in Group Ill at POD 5. It is concluded that the myocardial injury was closely related with the duration of cardiopulmonary bypass in open heart surgery.

• Archives of Pharmacal Research
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• v.21 no.3
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• pp.310-314
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• 1998

DW-116 is a new fluoroquinolone antimicrobial agent with a broad spectrum. In order to elucidate the resistance mechanism to DW-116 in Acinetobacter spp. bacteria, total chromosomal DNA was isolated from 10 strains of Acinetobacter spp. resistant to DW-116. Quinolone resistance determinant region (QRDR) of DNA gyrase gene was amplified by PCR. The 345 bp nucleotide fragment yielded was inserted into pKF 3 which was used as the vector. Comparisons of the DNA sequences of 8 strains with that of the wild type strain revealed a Ser-83 to Leu mutation in mutants and all ten strains contained one silent mutation$(T{\rightarrow}G)$in QRDR. From Acinetobacter MB4-8 strain, DNA gyrase was isolated and purified, through novobiocin-sepharose, heparin-sepharose affinity column chromatography. The enzyme was composed of two subunits and the molecular mass of subunits A and B were 75.6 and 51.9 kDa, respectively. The supercoiling activity of the reconstituted DNA gyrase composed of subunit A from Acinetobacter MB4-8 and subunit B from E. coli was not inhibited by $128{\mu}\textrm{g}$ml of ciprofloxacin. It might be said that one of the resistance mechanisms to DW-116 in Acinetohacter MB4-8 was subunit A alteration of DNA gyrase.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.5
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• pp.479-488
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• 2021

This study aimed to develop docetaxel (DTX) loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (DTX-NPs) and to evaluate the different pharmacological sensitivity of NPs to MCF-7 and MDA-MB-231 breast cancer cells. NPs containing DTX or coumarin-6 were prepared by the nanoprecipitation method using PLGA as a polymer and d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) as a surfactant. The physicochemical properties of NPs were characterized. In vitro anticancer effect and cellular uptake were evaluated in breast cancer cells. The particle size and zeta potential of the DTX-NPs were 160.5 ± 3.0 nm and -26.7 ± 0.46 mV, respectively. The encapsulation efficiency and drug loading were 81.3 ± 1.85% and 10.6 ± 0.24%, respectively. The in vitro release of DTX from the DTX-NPs was sustained at pH 7.4 containing 0.5% Tween 80. The viability of MDA-MB-231 and MCF-7 cells with DTX-NPs was 37.5 ± 0.5% and 30.3 ± 1.13%, respectively. The IC₅₀ values of DTX-NPs were 3.92- and 6.75-fold lower than that of DTX for MDA-MB-231 cells and MCF-7 cells, respectively. The cellular uptake of coumarin-6-loaded PLGA-NPs in MCF-7 cells was significantly higher than that in MDA-MB-231 cells. The pharmacological sensitivity in breast cancer cells was higher on MCF-7 cells than on MDA-MB-231 cells. In conclusion, we successfully developed DTX-NPs that showed a great potential for the controlled release of DTX. DTX-NPs are an effective formulation for improving anticancer effect in breast cancer cells.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.48 no.1
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• pp.21-32
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• 2022

Objectives: Inferior alveolar nerve block (IANB) is commonly used for mandibular dentoalveolar surgery. The objective of this study was to evaluate and compare the effectiveness of coadministration of dexamethasone (4 mg/mL) or adrenaline (0.01 mg/mL) as an adjuvant with lignocaine 2% in IANB during third molar surgery (TMS). Patients and Methods: This double-blind, randomized controlled trial was conducted between March and August 2020. The investigators screened patients needing elective TMS under local anesthesia. Based on strict inclusion and exclusion criteria, patients were enrolled in this study. These patients were assigned randomly into two study groups: dexamethasone group (DXN) or adrenaline group (ADN). Outcome variables were postoperative edema, trismus, visual analogue scale (VAS), perioperative analgesia, onset time, and duration of IANB. Results: Eighty-three patients were enrolled in this study, of whom 23 (27.7%) were eliminated or excluded during follow-up. This study thus included data from 60 samples. Mean age was 32.28±11.74 years, including 28 females (46.7%) in the ADN (16 patients, 57.1%) and DXN (12 patients, 42.9%) groups. The duration of action for DXN (mean±standard deviation [SD], 4:02:07±0:34:01 hours; standard error [SE], 0:06:00 hours; log-rank P=0.001) and for ADN (mean±SD, 1:58:34±0:24:52 hours; SE, 0:04:42 hours; log-rank P=0.001) were found. Similarly, time at which 1st analgesic consume and total number of nonsteroidal antiinflammatory drugs need to rescue postoperative analgesia was found statistically significant between study groups (t (58)=-11.95; confidence interval, -2:25:41 to -1:43:53; P=0.001). Early-hours VAS was also significantly different between the study groups. Conclusion: A single injection of dexamethasone prolongs the duration of action of lignocaine 2% IANB. Additionally, it can be used in cases where adrenaline is contraindicated.

• Food Science of Animal Resources
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• v.29 no.5
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• pp.627-632
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• 2009

The objective of this study was to investigate the supplementation effect of selenium on beef color stability. A total of 15 Hanwoo steers were divided into 3 groups and 2 groups were administered with 0.9 ppm of one of two organic-selenium products, Organic-Se and Se-SMC (Se-spent mushroom compost) for 4 mon. The third group was the control group, which was not with fed selenium during the same period. The result of this study showed that there was no significant difference in meat color between the control and treatments when Hunter $L^*$, $a^*$, $b^*$, chroma, hue and total color difference (${\Delta}E$) were measured after 30 min of blooming. When the oxymyoglobin (OxyMb) contents were measured after beef samples were ground and stored for 48 h at $20^{\circ}C$ in an incubator, they were 26.04%, 28.52% and 33.78% for the control, Organic-Se and Se-SMC after 14 d of storage and 12.65, 18.98 and 18.72 after 21 d of storage at $4^{\circ}C$, respectively (p<0.05). The control had a significantly higher metmyoglobin (MetMb) content than Organic-Se and Se-SMC (p<0.05). This result indicated that selenium supplementation was effective in preventing the oxidation of myoglobin(Mb) and production of MetMb and thus was able to maintain the purplish fresh red color of the meat.

• Journal of the Korean Chemical Society
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• v.31 no.4
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• pp.295-300
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• 1987

Spectroscopic studies have been carried out on the metachromatic behavior of methylene blue(MB) and acridine orange(AO) in the presence of chondroitin sulfate A(CSA) and chondroitin sulfate C(CSC). The characteristic changes of the meta-band with the changes of P/D value are discussed in terms of the stacking theory. Quantitative studies on the stacking effect are made to calculate the number of bound molecules of dye per unit molecule of the polyanion. The result shows that MB has stronger stacking effect than AO. A stacking model and the dimension of the bound dyes on the surface of the polyanion are proposed, on the basis of the dimer model of planar aromatic dyes and the most stable conformation of the CSA chain. The model is found to be reasonable in accordance with the experimental results.

• Biomolecules & Therapeutics
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• v.20 no.3
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• pp.313-319
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• 2012

In recent years, inhibition of HDACs has emerged as a potential strategy to reverse aberrant epigenetic changes associated with cancer, and several classes of HDAC inhibitors have been found to have potent and specific anticancer activities in preclinical studies. But their precise mechanism of action has not been elucidated. In this study, a novel synthetic inhibitor of HDAC, 3-(4-dimethylamino phenyl)-N-hydroxy-2-propenamide [IN-2001] was examined for its antitumor activity and the underlying molecular mechanisms of any such activity on human breast cancer cell lines. IN-2001 effectively inhibited cellular HDAC activity ($IC_{50}$ = 0.585 nM) inMDA-MB-231 human breast cancer cells. IN-2001 caused a significant dose-dependent inhibition of cell proliferation in estrogen receptor (ER) negative MDA-MB-231human breast cancer cells. Cell cycle analysis revealed that the growth inhibitory effects of IN-2001 might be attributed to cell cycle arrest at $G_0/G_1$ and/or $G_2$/Mphase and subsequent apoptosis in human breast cancer cells. These events are accompanied by modulating several cell cycle and apoptosis regulatory genes such as CDK inhibitors $p21^{WAF1}$ and $p27^{KIP1}$ cyclin D1, and other tumor suppressor genes such as cyclin D2. Collectively, IN-2001 inhibited cell proliferation and induced apoptosis in human breast cancer cells and these findings may provide new therapeutic approaches, combination of antiestrogen together with a HDAC inhibitor, in the hormonal therapy-resistant ER-negative breast cancers. In summary, our data suggest that this histone deacetylase inhibitor, IN-2001, is a novel promising therapeutic agent with potent antitumor effects against human breast cancers.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.484-490
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• 2012

The tin (IV) oxide nanoparticles are prepared by controlled precipitation method and calcined at temperatures of $200-600^{\circ}C$. The prepared $SnO_2$ nanoparticles characterized by XRD patterns, TEM image, IR and UV-Vis spectra. The XRD patterns and TEM image show the tetragonal structure and spherical morphology for $SnO_2$ nanoparticles, respectively. The photocatalytic activity of the prepared $SnO_2$ nanoparticles studied in degradation reaction of methylene blue (MB). The results show the size of nanoparticles, band-gap energy and photocatalytic activity of $SnO_2$ depends on the calcinations temperature. The $SnO_2$ nanoparticles calcined at $500^{\circ}C$ indicated the highest photoreactivity. Also, the zero-valent tin (ZVT) nanoparticles with tetragonal structure are prepared by a reducing agent and used as a catalyst in degradation of MB. In basic pH of 11, the degradation >95% of MB at time 150 min obtained at presence of ZVT nanoparticles.

• Nano
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• v.13 no.12
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• pp.1850142.1-1850142.9
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• 2018

Modified titanate nanotubes (TNT) were tested for their adsorption of methylene blue (MB) from water solutions. They were obtained from the $TiO_2$ nanopowder using a standard alkaline hydrothermal method but in the stage of acid washing, when the titanate flakes begin to roll into nanotubes, magnetite nanoparticles were added. The $Fe_3O_4$ magnetic nanoparticles with diameter of around 2 nm and 12 nm were used in the tests. Significantly stronger adsorption of MB was observed when smaller nanoparticles were used compared to using larger nanoparticles and compared to the case of unmodified nanotubes. It was shown that the increased adsorption of MB is associated with a more negative value of ${\zeta}$-potential for titanates modified by the ultra-small nanoparticles. In the adsorption experiment, pH 7 was selected. These results may prove to be of great importance in the case of potential applications corresponding to the use of such material for wastewater purification.