• Title/Summary/Keyword: ion effect

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DNA Breakage by Salvianolic acid B in the Presence of Cu (II) (구리이온(II)이 존재할 때 Salvianolic acid B에 의한 DNA 절단)

  • Lee, Pyeongjae;Moon, Cheol;Choi, Yoon Seon;Son, Hyun Kyu
    • Korean Journal of Clinical Laboratory Science
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    • v.50 no.2
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    • pp.205-210
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    • 2018
  • Salvianolic acid B, which is a compound in the Salvia miltiorrhiza, has diverse biological activities, In particular, the antioxidative effects were reported to be involved in the protection of hepatocytes, neurons, and various cell types. On the other hand, some phenolic compounds, such as ferulic acid, which is regarded as an antioxidant, plays a pro-oxidative role in the specific transitional metal environment, which could explain the anticancer effect. This study examined the pro-oxidative effects of salvianolic acid B in the presence of $Cu^{2+}$. Treatment with both salvianolic acid B and $Cu^{2+}$ induced the transition of supercoiled DNA to the open circular or linear form but not in the sole salvianolic acid B or $Cu^{2+}$ treatments. Salvianolic acid B reduced the $Cu^{2+}$ to $Cu^+$ using neocuproine, a $Cu^+$ specific chelator. In addition, catalase, an enzyme that breaks down the $H_2O_2$ to water and molecular oxygen, inhibited the DNA breakage. $H_2O_2$, a reactive oxygen species, has detrimental effects on biological molecules, particularly DNA. Overall, the reduction of $Cu^{2+}$ by salvianolic acid B could lead to the production of $H_2O_2$ followed by DNA breakage. These results suggest that the pro-oxidative effects could be the one of the anti-cancer mechanisms of salvianolic acid B, which remains to be explained.

Antioxidant Activity of Fermented Wild Grass Extracts (산야초 발효액의 항산화 활성)

  • Lee, Young-Jun;Yoon, Bo-Ra;Kim, Dan-Bi;Kim, Myoung-Dong;Lee, Dae-Won;Kim, Jae-Keun;Lee, Ok-Hwan
    • The Korean Journal of Food And Nutrition
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    • v.25 no.2
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    • pp.407-412
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    • 2012
  • Wild grass is edible, and it grows in the mountains or field areas. Wild grass has diverse biological effects, such as antiobesity, anti-cancer, antioxidant activities and immune stimulation. Currently, many studies are aimed at enhancing the efficacy of medicinal foods on biological activity using a bioconversion technology, including the fermentation process. In this study, the quality characteristics and antioxidative activity of the fermented wild grass was investigated. The antioxidant activity of fermented wild grass was assessed by various radical scavenging assays using DPPH(2,2-diphenyl-1-picrylhydrazyl), FRAP(ferric ion reducing antioxidant power), reducing power, and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)). Moisture contents of the fermented wild grass is $49.6{\pm}0.06%$. Contents of crude ash, crude protein, and crude fat were $0.65{\pm}0.01$, $0.65{\pm}0.04$, and $3.3{\pm}0.59%$, respectively. Moreover, fermented wild grass showed that the hunter's color values were 80.36(lightnees), 11.47(redness), and 44.53(yellowness), respectively. Total phenolic contents of the fermented wild grass was $1,185{\pm}159{\mu}g$ GAE(gallic acid equivalent)/g. The antioxidative activities of the fermented wild grass were significantly increased in a dose dependent manner. In addition, fermented wild grass did not show any cytotoxicity up to 500 ${\mu}g/m{\ell}$. However, the anti-adipogenic effect of the fermented wild grass extract was barely detectable. This antioxidant potential is partly due to the phenolic compounds that are present in the fermented wild grass extracts.

Functionality of Extracted Proteins by Additives and Ionic Strength (첨가제의 종류와 이온강도에 따라 추출되는 육단백질의 기능적 특성)

  • Rhee, Min-Suk;Lee, Jun-Sup;Koh, Kyung-Chul;Kim, Young-Kyo;Kim, Byoung-Chul
    • Korean Journal of Food Science and Technology
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    • v.30 no.1
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    • pp.69-76
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    • 1998
  • This study was investigated to determine the effect of additives and ionic strength on the functionality of extracted proteins in preblends in order to use less additive in restructured meat products. Preblends contained the combinations of sodium chloride (NaCl; 0, 4.5, 9.0%), sodium tripolyphosphate (STPP; 0, 2.5, 5.0%), and tetrasodium pyrophosphate (PP; 0, 2.44, 4.88%). The pH values increased linearly with increasing STPP and PP concentrations (p<0.01). In the equivalent ionic strengths, PP was more effective than STPP in increasing pH. Phosphate ions were more effective on total extractable protein (used 1 M NaCl buffer) than chloride ion at equivalent ionic strengths. Solubility was decreased by adding NaCl and increasing total extractable proteins. Meat sulfhydryl contents were high with increasing total extractable proteins. When protein extracts were heated at $65^{\circ}C$, 7 min, meat sulfhydryl contents decreased and surface hydrophobicity increased (p<0.01). However, all protein extracts showed no differences in SDS-PAGE pattern. In conclusion, PP is more effective than STPP in order to use less additive but there was no linear relationship between functionnal improvement and ionic strength.

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Purification and Characterization of a Novel Neuvopeptide with a Smooth Muscle-Relaxing Activity from the Starfish, Asterina pectinifera (별불가사리(Asterina pectinifera)로부터 새로운 평활근 이완활성 펩타이드의 정제)

  • KIM Eun Jung;KIM Chan-Hee;GO Hye-Jin;KIM In Hae;AN Sang Hyun;SOHN Hee-Young;PARK Hee Yeon;YOON Ho Dong;CHANG Young-Chae;HONG Yong-Ki;PARK Nam Gyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.38 no.3
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    • pp.148-152
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    • 2005
  • A novel neuropeptide with a relaxing activity on the dorsal retractor muscle (DRM) was isolated from the whole body extract of the starfish, Asterina pectinifera. The peptide was purified by gel-filtration ion-exchange and $C_{18}$ reversed-phase HPLC. The complete amino acid sequence of this peptide, which was determined by automated Edman degradation and MALDI-TOF mass, was Phe-Gly-Lys-Gly-Gly-Ala-Tyr-Asp-Pro-Leu-Ser-Ala-Gly-Phe-Thr-Asp. A comparison of the amino acid sequence with those of other known neuropeptides revealed that the asteripectin was a novel neuropeptide with smooth muscle-relaxing activity on the starfish DRM. This peptide showed threshold response to relaxing activity on the DRM at $10^{-10}M$ and the maximal relaxing effect was $120{\pn}7.0\%$ at $10^{-5}M$. The relaxing activity of this peptide on the starfish DRM increased in a dose-dependent manner.

THE EFFECT OF DIFFERENTIAL MODULATION OF N-METHYL-D-ASPARTATE RECEPTOR ON THE PROLIFERATION OF PRIMARY CULTURED NORMAL HUMAN ORAL KERATINOCYTES: DNA SYNTHESIS RATE ANALYSIS (N-methyl-D-aspartate 수용기의 다양한 조절이 일차 배양된 정상사람구강각화세포의 증식에 미치는 영향; DNA 합성율 평가)

  • Kim, In-Soo;Paik, Ki-Suk;Chang, Mi-Sook;Lee, Won;Lee, Seung-Pyo
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.2
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    • pp.124-130
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    • 2007
  • In the present study, I investigated the effects of N-methyl-D-aspartate (NMDA), arachidonic acid (AA), and Nitric Oxide Synthase Inhibitor (NOSI), alone or in combination, on the proliferation of cultured primary normal human oral keratinocytes (NHOK). The purpose of this study was therefore the preliminary study for the examination of the interaction between these agents and NHOK in order to elucidate the mechanisms by which epithelial growth and regeneration are regulated. NHOK were obtained from gingival tissue of 20 individuals aged 20 to 29, and third passage (P3) cells were used for this study. The DNA synthesis was measured by the BrdU assay. Addition of low concentration of AA ($1{\mu}M$) and high concentration of AA with NMDA group (NMDA+AA $10{\mu}M$) made DNA synthesis rate increase significantly at the early stage. Adding NNA ($10{\mu}M$) affected DNA synthesis rate to increase significantly in 4 hours. At the early stage, DNA synthesis was significantly active in the NOS-I with NMDA groups than in the control and the NMDA-only group, while it didn't become statistically meaningful in 24 hours. AA $1{\mu}M$ and NNA $10{\mu}M$ may induce the proliferation of the NHOK independently and NOS-I may induce the proliferation of the NHOK with NMDA. These reactions might be related to the NMDA receptor in the cell and the change of the intracellular calcium ion concentration.

The effects of Hydroxyapatite nano-coating implants on healing of surgically created circumferential gap in dogs

  • Chae, Gyung-Joon;Lim, Hyun-Chang;Choi, Jung-Yoo;Chung, Sung-Min;Lee, In-Seop;Cho, Kyoo-Sung;Kim, Chong-Kwan;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • v.38 no.sup2
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    • pp.373-384
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    • 2008
  • Purpose: The aim of this study is to compare the healing response of various Hydroxyapatite(HA) coated dental implants by Ion-Beam Assisted Deposition(IBAD) placed in the surgically created circumferential gap in dogs. Materials and methods: In four mongrel dogs, all mandibular premolars and the first molar were extracted. After an 8 weeks healing period, six submerged type implants were placed and the circumferential cylindrical 2mm coronal defects around the implants were made surgically with customized step drills. Groups were divided into six groups : anodized surface, anodized surface with 150nm HA and heat treatment, anodized surface with 300nm HA and heat treatment, anodized surface with 150nm HA and no heat treatment, and anodized surface with 150nm HA, heat treatment and bone graft, anodized surface with bone graft. The dogs were sacrificed following 12 weeks healing period. Specimens were analyzed histologically and histomorphometrically. Results: During the healing period, healing was uneventful and implants were well maintained. Anodized surface with HA coating and $430^{\circ}C$ heat treatment showed an improved regenerative characteristics. Most of the gaps were filled with newly regenerated bone. The implant surface was covered with bone layer as base for intensive bone formation and remodeling. In case that graft the alloplastic material to the gaps, most of the coronal gaps were filled with newly formed bone and remaining graft particles. The bone-implant contact and bone density parameters showed similar results with the histological findings. The bone graft group presented the best bone-implant contact value which had statistical significance. Conclusion: Within the scope of this study, nano-scale HA coated dental implants appeared to have significant effect on the development of new bone formation. And additional bone graft is an effective method in overcoming the gaps around the implants.

THE EFFECTS OF IONS AND BUFFER SOLUTIONS ON THE MRNA EXPRESSION OF gtfD GENE OF Streptococcus mutans (Streptococcus mutans의 gtfD 유전자 발현에 대한 이온 및 완충액의 영향)

  • Kim, Bo-Young;Kim, Shin;Chung, Jin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.31 no.2
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    • pp.314-322
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    • 2004
  • The production of a glucan was affected by the concentration of ions and buffer solutions, and nutrients in an oral cavity. In this study, the effects of ions and buffer solutions on the mRNA expression of gtfD gene in Streptococcus mutans, an important causative agent of dental caries, were investigated by Fluorescent in situ hybridization(FISH). At first, ions and buffer solutions had little effect on the multiplication of Streptococcus mutans. The green fluorescence according to the mRNA expression of gtfD gene was detected in the BHI broth containing 1% sucrose. The intensities of the green fluorescence were strong at 0.25mM of $CaCl_2$. Little fluorescence was detected by the addition of KCl, except far 10mM KCl at which fluorescence intensities were similar to those of the control. Fluorescence intensities were weak at each concentration of $MgCl_2$ when compared to the control. As for buffer solutions, fluorescence intensities were similar to those of the control at each concentration of buffer solutions, except that they were little detected at 100mM of potassium phosphate.

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THE FLUORIDE RELEASING EFFECT OF PVA FLUORIDE-POLYMER ADHESIVE TAPE (불소를 함유한 PVA 고분자 접착 테잎의 불소 유리 효과)

  • Im, Sung-Ok;Lee, Sang-Ho;Lee, Nan-Young;Park, Seung-Hyo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.38 no.4
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    • pp.327-336
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    • 2011
  • The purpose of this study is to investigate the residual fluoride concentration of polymer adhesive tape in oral cavity which is made by spraying NaF on PVA base and to compare with Fluoride varnish(Cavityshiled$^{TM}$). Experimental groups were divided into two according to application methods; Group 1(NaF-PVA tape) and Group 2(Cavityshiled$^{TM}$). Topical fluoride was applied to 20 healthy adults aged from 25 to 30. Fluoride concentration in unstimulated whole saliva was measured by fluoride-sensitive electrode for 72 hours. 1. Until 72 hours after application in every group, significantly higher fluoride concentration was shown in saliva than baseline value(p<0.05). 2. At 2, 3 and 4 hours after application, Group 2 revealed significantly higher fluoride concentration than Group 1(p<0.05). 3. At 24, 48 and 72 hours after application, there was no significance(p>0.05). Although the residual fluoride concentration of saliva and the amount of fluoride of NaF-PVA tape are lower than those of Cavityshield$^{TM}$, NaF-PVA tape is considered to be more effective since it showed almost the same result as Cavityshield$^{TM}$. Therefore, NaF-PVA tape is expected to be a great fluoride application material.

Prediction of Midline Dose from Entrance and Exit Dose Using OSLD Measurements for Total Body Irradiation

  • Choi, Chang Heon;Park, Jong Min;Park, So-Yeon;Chun, Minsoo;Han, Ji Hye;Cho, Jin Dong;Kim, Jung-in
    • Journal of Radiation Protection and Research
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    • v.42 no.2
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    • pp.77-82
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    • 2017
  • Background: This study aims to predict the midline dose based on the entrance and exit doses from optically stimulated luminescence detector (OSLD) measurements for total body irradiation (TBI). Materials and Methods: For TBI treatment, beam data sets were measured for 6 MV and 15 MV beams. To evaluate the tissue lateral effect of various thicknesses, the midline dose and peak dose were measured using a solid water phantom (SWP) and ion chamber. The entrance and exit doses were measured using OSLDs. OSLDs were attached onto the central beam axis at the entrance and exit surfaces of the phantom. The predicted midline dose was evaluated as the sum of the entrance and exit doses by OSLD measurement. The ratio of the entrance dose to the exit dose was evaluated at various thicknesses. Results and Discussion: The ratio of the peak dose to the midline dose was 1.12 for a 30 cm thick SWP at both energies. When the patient thickness is greater than 30 cm, the 15 MV should be used to ensure dose homogeneity. The ratio of the entrance dose to the exit dose was less than 1.0 for thicknesses of less than 30 cm and 40 cm at 6 MV and 15 MV, respectively. Therefore, the predicted midline dose can be underestimated for thinner body. At 15 MV, the ratios were approximately 1.06 for a thickness of 50 cm. In cases where adult patients are treated with the 15 MV photon beam, it is possible for the predicted midline dose to be overestimated for parts of the body with a thickness of 50 cm or greater. Conclusion: The predicted midline dose and OSLD-measured midline dose depend on the phantom thickness. For in-vivo dosimetry of TBI, the measurement dose should be corrected in order to accurately predict the midline dose.

Thermal Stability Enhancement of Nickel Monosilicides by Addition of Pt and Ir (Pt와 Ir 첨가에 의한 니켈모노실리사이드의 고온 안정화)

  • Yoon, Ki-Jeong;Song, Oh-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.13 no.4
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    • pp.27-36
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    • 2006
  • We fabricated thermally evaporated 10 nm-Ni/(poly)Si, 10 nm-Ni/l nm-Ir/(poly)Si and 10 nm-Ni/l nm-Pt/(poly)Si films to investigate the thermal stability of nickel monosilicides at the elevated temperatures by rapid annealing them at the temperatures of $300{\sim}1200^{\circ}C$ for 40 seconds. Silicides of 50 nm-thick were formed on top of both the single crystal silicon actives and the polycrystalline silicon gates. A four-point tester was used to examine sheet resistance. A scanning electron microscope and field ion beam were employed for thickness and microstructure evolution characterization. An X-ray diffractometer and an Auger depth profiler were used for phase and composition analysis, respectively. Nickel silicides with platinum have no effect on widening the NiSi stabilization temperature region. Nickel silicides with iridium farmed on single crystal silicon showed a low resistance up to $1200^{\circ}C$ while the ones formed on polycrystalline silicon substrate showed low resistance up to $850^{\circ}C$. The grain boundary diffusion and agglomeration of silicides lowered the NiSi stable temperature with polycrystalline silicon substrates. Our result implies that our newly proposed Ir added NiSi process may widen the thermal process window for nano CMOS process.

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