• Textile Coloration and Finishing
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• v.13 no.2
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• pp.28-28
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• 2001

Four kinds of neutral sodium salts with different anions, NaF, NaCl, NaBr, and NaI, were added to the dye bath to accurately understand the effect of anions on the reactive dyeing of silk with C. I. Reactive Black 5. The sodium cation lowered the negative surface potential of the silk and increased the dye-uptake on fille fabric as reported previously. However, because of the discrepancy in the anions′inhibition power from cation′s lowering the surface negative potential the amount of the dye on the silk fiber was different from each other in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$. The activation energy($E_a$) for the dyeing was in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$ but the dye-uptake on the fabric and the activation free energy(Δ$G^*$), the real energy barrier for the reaction, were in the order of $F^-\;>\;Cl^-\;>\; Br^-\;>\;I^-$ because the strength of the interaction of the anions with sodium cations was the same as the order of the latter. In other words $F^-$ exerted the weakest electrostatic force on $Na^+$and competed with the dyestuff anions least of all. The decrease in Δ$S^*$may be due to the looesly bonded activated complex of dyestuff anions, sodium cations and fiber molecules at transition state. It was clarified from the Bronsted equation that sodium salts with different anions also had fille ionic strength effect and the specific salt effect on the reactive dyeing.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.289-292
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• 1995

Fig leaves were extracted with methanol and then fractionated with ethyl acetate and various buffers to get active fractions, and their antimicrobial activities in each fraction were determined. Acidic fraction and phenolic fraction of fig leaves showed strong antimicrobial activities, but the basic fraction and neutral fraction did not show any activities. The degree of antimicrobial activities in phenolic fraction against tested bacteria were higher than those in acidic fraction, but these against yeasts and mold were almost equivalent to those in acidic fraction. Especially, phenolic fraction showed the strongest activities against Staphylococcuns aureus and Pseudomonas aeruginosa. Although there were some differences among microorganisms, minimum inhibition concentrations(MIC) in acidic and phenolic fractions against tested microorganisms were 0.05 to 0.1 g eq./ml and 0.01 to 0.25 g eq./ml, on the basis of fresh sample weight, respectively. Minimum lethal concentrations(MLC) in acidic and phenolic fractions were 0.25 to 2.00 g eq./ml and 0.05 to 1.50 g eq./ml, respectively. These supposed the antimicrobial activities in phenolic fraction were generally higher than those in acidic fraction and also phenolic fraction had lower MIC and MLC values than acidic fraction.

• The korean journal of orthodontics
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• v.42 no.1
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• pp.17-22
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• 2012

Objective: To study and compare the effects of different demineralization-inhibition methods on the shear bond strength (SBS) and fracture mode of an adhesive used to bond orthodontic brackets to demineralized enamel surfaces. Methods: Eighty freshly extracted, human maxillary premolars were divided into 4 equal groups and demineralized over the course of 21 days. Brackets were bonded to the demineralized enamel of teeth in Group 1. In Group 2, bonding was performed following resin infiltration ($ICON^{(R)}$, DMG, Hamburg, Germany). Before bonding, pre-treatment with acidulated phosphate fluoride (APF) or solutions containing casein phosphopeptide-amorphous calcium phosphate with 2% neutral sodium fluoride (CPP-ACP/wF) was performed in Groups 3 and 4, respectively. The SBS values of the brackets were measured and recorded following mechanical shearing of the bracket from the tooth surface. The adhesive remnant index (ARI) scores were determined aft er the brackets failed. Statistical comparisons were performed using one-way ANOVA, Tukey's post-tests, and G-tests. Results: Significant differences were found in some of the intergroup comparisons of the SBS values (F = 39.287, p < 0.001). No significant differences were found between the values for the APF-gel and control groups, whereas significantly higher SBS values were recorded for the resin-infiltrated and CPP-ACP/wF-treated groups. The ARI scores were also significantly different among the 4 groups (p < 0.001). Conclusions: Tooth surfaces exposed to resin infiltration and CPP-ACP/wF application showed higher debonding forces than the untreated, demineralized surfaces.

• Journal of the Korean Society of Tobacco Science
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• v.19 no.2
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• pp.136-144
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• 1997

Cigarette smoking is known to suppress both 1-methy14-phenyl-155,Ltetrahydropy-ridine (MPTP)-induced parkinsonism and idiopathic Parkinson's disease (PD). However, the precise mechanism underlying its protective action against PD is not clearly elucidated yet. In order to find possible clue on the mechanism of protective action of smoking, we investigated the inhibitory effect of cigarette smoke components on rat brain mitochondria1 monoamine oxidase B (MAO-B), responsible enzyme for the activation of MPTP to its toxic metabolitesr and identified the components having an inhibitory potency on this enzyme from cigarette smoke. Total 31 eligible constituents including nicotine were selected from cigarette smoke condensates via solvents partitioning and silica gel chromatographic separation, and inhibitory potencies of 19 components on MAO-B were determined. Hydroquinone and methylcatechol, the phenolic components, showed the strongest inhibitory potencies on MAO-B activity in the components tested. 3,4-Dihydroxybenzylamino, myosmine and indole in basic fracton, eugenol in phenolic fraction, and farnesol in neutral fraction also inhibited the enzyme activity dose-dependently. Among tobacco alkaloids tested only myosmine was effective for the inhibition of this enzyme. These results suggest that the decrease in MAO-B activity by such components derived from cigarette smoke seems to be related to the suppression of MPTP-induced neurotoxicity and to the less incidence of Parkinson's disease in smokers than in nonsmokers.

• Archives of Pharmacal Research
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• v.29 no.3
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• pp.241-248
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• 2006

Angiotensin converting enzyme (ACE) inhibitors have cardioprotective effects in different species including human. This cardioprotective effect is mainly due to the inhibition of bradykinin (BK) degradation rather than inhibition of the conversion of angiotensin I to angiotensir. II. Bradykinin, a nonapeptide, has been considered to be the potential target for various enzymes including ACE, neutral endopeptidase 24.11, carboxypeptidase M, carboxypeptidase N, proline aminopeptidase, endopeptidase 24.15, and meprin. In the present study, the coronary vascular beds of Sprague Dawley rat isolated hearts were perfused (single passage) with Krebs solution alone or with different concentrations of BK i.e. $2.75{\times}10^{-10},\;10^{-7},\;10^{-6}\;and\;10^{-5}M$ solution. Percent degradation of BK was determined by radioimmunoassay. The degradation products of BK after passing through the isolated rat-hearts were determined using RP-HPLC and mass spectroscopy. All the four doses of BK significantly decreased the perfusion pressure during their passage through the hearts. The percentage degradation of all four doses was decreased as the concentration of drug was increased, implying saturation of a fixed number of active sites involved in BK degradation. Bradykinin during a single passage through the hearts degraded to give [1-7]-BK as the major metabolite, and [1-8]-BK as a minor metabolite, detected on HPLC. Mass spectroscopy not only confirmed the presence of these two metabolites but also detected traces of [1-5]-BK and arginine. These findings showed that primarily ACE is the major cardiac enzyme involved in the degradation of bradykinin during a single passage through the coronary vascular of bed the healthy rat heart, while carboxypeptidase M may have a minor role.

• Journal of the Korean Society of Tobacco Science
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• v.2 no.2
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• pp.8-13
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• 1980

The inhibition effect of flavone and butylatedhydroxyanisole (BHA) on the microsomal activation of Cigarette Smoke Condensate (CSC) or its Neutral Portion (NP) was investigated in Rat. The activities of Latic acid dehydrogenase (LDH) in serum was measured in the time intervals of 3, 6, 12, 18, 24 and 30 hr, respectively, after the injection (ip) of CSC (5mg/kg) or NP (10mg/kg) to Wistar male rat. Flavone (1mg/kg) and BHA (1mg/kg) were injected along with CSC or NP. The significant enhancement of the LDH activity in serum was observed in both cases of rats treated with CSC and NP. A drastic decrease of LDH activity from 1040 unit to 641 unit was observed after 12 hours of injection of CSC along with flavone. In contrast with the case of flavone, BHA reduced the enzyme activity from 825 unit to 652 unit at the same condition of flavone. Therefore, flavone can be considered to be a better inhibitor on action of CSC in vivo.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4357-4361
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• 2015

Thunbergia Laurifolia Linn. (TL) is one of the most familiar plants in Thai traditional medicine that is used to treat various conditions, including cancer. However, the antitumor activity of TL or its constituents has never been reported at the molecular level to support the folklore claim. The present study was designed to investigate the antitumor effect of an aqueous extract of TL in human breast cancer cells and the possible mechanism(s) of action. An aqueous crude extract was prepared from dried leaves of TL. Folin-Ciocalteu colorimetric assays were used to determine the total phenolic content. Antiproliferative and cell cycle effects were evaluated in human breast adenocarcinoma MCF-7 cells by MTT reduction assay, cell growth inhibition, clonogenic cell survival, and flow cytometric analysis. Free radical generation by the extracts was detected using electron paramagnetic resonance spectroscopy. The exposure of human breast adenocarcinoma MCF-7 cells to a TL aqueous extract resulted in decreases in cell growth, clonogenic cell survival, and cell viability in a concentration-dependent manner with an $IC_{50}$ value of $843{\mu}g/ml$. Treatments with extract for 24h at $250{\mu}g/ml$ or higher induced cell cycle arrest as indicated by a significant increase of cell population in the G1 phase and a significant decrease in the S phase of the cell cycle. The capability of the aqueous extract to generate radical intermediates was observed at both high pH and near-neutral pH conditions. The findings suggest the antitumor bioactivities of TL against selected breast cancer cells may be due to induction of a G1 cell cycle arrest. Cytotoxicity and cell cycle perturbation that are associated with a high concentration of the extract could be in part explained by the total phenolic contents in the extract and the capacity to generate radical intermediates to modulate cellular proliferative signals.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.115-121
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• 1988

Although Saponin A from Panax ginseng has previously been shown to inhibit carageenin induced edema. a paucity of information exists on the effects of components from ginseng on the cellular inflammatory response. specifically polymorphonuclear leukocyte (PMNL) function. The purpose of this study was 10 determine the effects of isolated neutral dammarane saponins from ginseng (i.e..glycosidic derivatives of 20(S)-protopanaxadiol [ginsenoside $Rb_1,\;Rb_2$ and Rc] and 20(S)-protopanaxatriol [ginsenosides Re and $Rg_1$]) on in vivo PMNL function and to compare their effects with those produced by a steroidal anti-inflammatory agent (dexamethasone) and commercially available saponin. Dexamethasone. the ginsenosides and saponin were all shown to he potent inhibitors of PMNL chemotaxis using the $^{51}Cr$ assay with $5{\times}10^{-8}M$ f-met-leu-phe [FMLP] as the chemoattractant. Inhibition or PMNL chemotaxis by dexamethasone. the ginsenosides and saponin were all shown to be both time-and dose-dependent and these agents did not affect cellular viability at the concentrations tested Saponin and the ginsenosides were more potent inhibitors of chemotaxis than was dexamethasone. while oxidant generation (as measured by the luminol-enhaneed chemil-uminescence of PMNL using FMNL $[10^{-6}]$ as the stimulus) was inhibited by dexamethasone. the ginsenosides $(Rb_1\;Rb_2\;Rc\;Re\;and\;Rg_1)$ and saponin at a concentration of 1 ${\mu}M$ had no significant effect on PMNL chemiluminescence. Thus. the neutral dammarane saponins are potentially important modulators or PMNL function and their inhibitory effects may he differentiated from those of the Steroidal anti-inflammatory agents.

• Archives of Pharmacal Research
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• v.7 no.2
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• pp.87-93
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• 1984

The effects of ionic strength and pH on the binding of cefazolin to bovine serum albumin (BSA) were studied by UV difference spectrophotometry. As ionic strength at constant pH and temperature increases, the apparent bining constant decreased but the number of binding sites remained almost constant at 2. The constancy of the number of binding sites with increasing the ionic strength suggests that purely electrostatic forces between BSA and drug do not have great importance in the drug binding, even though there is a decrease in the apparent binding constant. Thus, the effect of ionic strength on the interaction between drug and BSA may be explained by the changes in ionic atmosphere of the aggregated BSA molecules and competitive inhibition by phosphate ions. In addition, the higher apparent binding constant at high ionic strength is explained by conformational changes of BSA from its aggregate forms into subunits. The pH effects on the afinity of interactions indicated that the binding affinity of cefazoline is higher in the neutral region than in the alkaline region. An d at high pH value, the number of binding sites decreased from 2 to 1 because of the conformational change of BSA in the alkaline region.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.3
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• pp.207-214
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• 1997

We collected airborne complex mixtures in a industrial area of Yeochun, and examined whether these complex mixtures could affect gap junctional intercellular communication (GJIC) in a cultured WBF-344 rat liver epithelial cells (LEC). Since the reduction of GJIC plays an important role in chemical carcinogenesis, measurement of changes of GJIC is a meaningful method to screen carcinogenicity of these mixtures. High and low volume samples were dissolved in dimethyl sulfoxide (DMSO) and tested. Blank filter extractions were also examined for exclud-ing possible toxicity of filter itself, and TPA (12-O-tetradecanoylphorbol-13-acetate) and DMSO were used as positive and negative control, respectively. When the cells were exposed to samples at concentration below that required to maintain rather than 85% cell viability based on the result of neutral red uptake assay, maximal inhibition of GJIC was observed at 1hr after treatment with both high and low volume samples by scrape-loading dye transfer assay. In fluorescence recovery after photobleaching assay, recovery rates via gap junctions were 33%/min in high volume sample and 62%/min in low volume sample. In together, airborne samples collected in Yeochun inhibited GJIC in a cultured WBF-344 rat LEC. These results suggest airborne samples tested in this experiment may attribute to cause a certain type and degree of cancers in in vivo when exposured for some periods.