• 제목/요약/키워드: PG

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Tetraphenylborate 음이온과 Pyronin G의 회합에 관한 분광학적 특성 (Spectroscopic Characterization on the Aggregation Behavior of Pyronin G with Tetraphenylborate anion)

  • 이범규;김강진
    • 분석과학
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    • 제8권1호
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    • pp.47-53
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    • 1995
  • 수용액에서 $TPB^-$$PG^+$의 회합을 흡수 및 형광분광법으로 연구하였다. 1, 4-dioxane을 PG-TPB 수용액에 첨가하면 순수한 물보다 용매의 소수성이 증가되어 $PG^+$$TPB^-$ 사이의 회합체가 해리되었고, $PG^+$만의 수용액보다 $PG^+$ 단위체의 농도가 더 크게 나타났다. 물을 제외한 모든 유기 용매에서 회합은 관찰되지 않았고, 최대 흡수는 ${\pi}^*$ 척도와 $(n^2-1)/(2n^2+1)$ 함수를 사용하였을 때가 비교적 좋은 직선 관계를 주었다. 그러나 알코올의 경우는 ${\pi}^*$ 척도를 사용하였을 때가 더 훌륭한 직선 관계를 주었다.

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Poly (lactide)-b-Poly (glycerol) 블록 공중합체의 중합 (Synthesis of Poly (lactide)-b-Poly (glycerol) (PLA-b-PG) Block Copolymer)

  • 이존환;오성근;김용진
    • 대한화장품학회지
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    • 제43권2호
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    • pp.165-174
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    • 2017
  • 이 연구는 소수성 폴리락타이드(PLA) 블록과 친수성 하이퍼브랜치드 폴리글리세롤(hbPG) 블록으로 구성된 양친매성 블록 공중합체(PLA-b-hbPG)의 합성방법에 대한 것이다. 또한, hbPG 블록을 4-hydroxyl cinnamic acid (CA)로 에스터 반응화하여, 광가교가 가능한 블록 공중합체인 PLA-b-hbPG-CA에 대한 접근법에 대해서도 보고하였다. 연구된 양친성 고분자는 친수기에 많은 양으로 존재하는 폴리글리세롤에 의해 화장품용 약물 전달체로 사용이 가능한 작은 크기(100 nm)의 마이셀을 형성함을 확인하였다. 또한, hbPG으로 구성된 마이셀의 corona 부분은 우수한 친수성을 나타내어 생체 내 독성을 최소화할 수 있음을 확인하였다. 소수성 활성성분이 담지된 PLA-b-hbPG-CA 마이셀은 생체적합성 및 자기조립구조에 의해 화장품용 약물 전달체로 활용이 가능할 것으로 기대된다.

A murine periodontitis model using coaggregation between human pathogens and a predominant mouse oral commensal bacterium

  • Liu, Mengmeng;Choi, Youngnim
    • Journal of Periodontal and Implant Science
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    • 제52권2호
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    • pp.141-154
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    • 2022
  • Purpose: C57BL/6 mice, which are among the most common backgrounds for genetically engineered mice, are resistant to the induction of periodontitis by oral infection with periodontal pathogens. This study aimed to develop a periodontitis model in C57BL/6 mice using coaggregation between human pathogens and the mouse oral commensal Streptococcus danieliae (Sd). Methods: The abilities of Porphyromonas gingivalis ATCC 33277 (Pg33277), P. gingivalis ATCC 49417 (Pg49417), P. gingivalis KUMC-P4 (PgP4), Fusobacterium nucleatum subsp. nucleatum ATCC 25586 (Fnn), and F. nucleatum subsp. animalis KCOM 1280 (Fna) to coaggregate with Sd were tested by a sedimentation assay. The Sd-noncoaggregating Pg33277 and 2 Sd-coaggregating strains, PgP4 and Fna, were chosen for animal experiments. Eighty C57BL/6 mice received oral gavage with Sd once and subsequently received vehicle alone (sham), Fna, Pg33277, PgP4, or Fna+PgP4 6 times at 2-day intervals. Mice were evaluated at 5 or 8 weeks after the first gavage of human strains. Results: Fnn, Fna, and PgP4 efficiently coaggregated with Sd, but Pg33277 and Pg49417 did not. Alveolar bone loss was significantly higher in the PgP4 group at both time points (weeks 5 and 8) and in all experimental groups at week 8 compared with the sham group. The PgP4 group presented greater alveolar bone loss than the other experimental groups at both time points. A higher degree of alveolar bone loss accompanied higher bacterial loads in the oral cavity, the invasion of not only PgP4 but also Sd and Fna, and the serum antibody responses to these bacteria. Conclusions: Periodontitis was successfully induced in C57BL/6 mice by oral infection with a P. gingivalis strain that persists in the oral cavity through coaggregation with a mouse oral commensal bacterium. This new model will be useful for studying the role of human oral bacteria-host interactions in periodontitis using genetically engineered mice.

다이옥신류에 의한 한국인의 폭로 현황 및 리스크 평가 (Residue and Risk Assessment of Polychlorinated dibenzo-p-dioxin/dibenzofurans in the Korean Population)

  • 강윤석;박종세;민병윤
    • 분석과학
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    • 제15권3호
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    • pp.270-286
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    • 2002
  • 서울, 마산 그리고 진주 지역에 거주하는 일반인 체내에 잔류하는 PCDDs/DFs의 축적 레벨은 독성등량으로 환산하여 PCDDs가 평균 9 pg I-TEQ/g(0.2 ~ 30 pg TEQ/g 지방 중량), PCDFs가 8 pg I-TEQ/g (0.8 ~ 25 pg TEQ/g)으로 계산되어졌다. 한편 마산 지역에서 채취된 모유 샘플의 경우 PCDDs가 평균 13 pg I-TEQ/g (lipid wt.), PCDFs가 평균 4.8 pg I-TEQ/g으로 각각 검출되어졌다. 전반적으로 한국인 체내의 PCDDs/DFs의 잔류레벨은 구미 선진국과 비교하여 낮은 수준임을 확인 할 수 있었다. 유아에 있어 수유를 통한 PCDDs/DFs의 일일 폭로량은 유아 체중을 5 kg, 일일 모유 섭취량을 800 mL 로 가정하여 계산되어졌으며, 그 계산 결과 유아의 2,3,7,8-TeCDD의 폭로량은 39 pg/kg body weight/day 이었으며, 총 TEQ로 환산 할 경우 86 pg/kg/day로 계산되어졌다. 이러한 폭로 레벨은 미국의 실질 안전계수(0.001 pg/kg/day) 혹은 WHO가 설정한 TDI(4 pg/kg/day)를 훨씬 초과하는 수준으로, 단기간이지만 수유기에 이루어지는 다량의 PCDDs/DFs의 폭로에 대한 적절한 리스크 평가와 대책 마련이 필요한 것으로 사료된다.

장생도라지 (Platycodon grandiflorum)의 항산화 활성 평가 (Evaluation of Antioxidant Activity of Platycodon grandiflorum)

  • 김충현;정봉용;정선기;이철호;이현선;김봉희;김상겸
    • Environmental Analysis Health and Toxicology
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    • 제25권1호
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    • pp.85-94
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    • 2010
  • Platycodon grandiflorum, Doraji as Korean name, is one of the most widely used traditional oriental medicine for bronchial diseases and also used as a folk remedy for geriatric diseases and inflammatory diseases. In recent studies, it has been reported that some effect of P. grandiflorum is derived from its antioxidant activity, although there is still a lack of evidence to establish its oxy-radical scavenging activity. In this study, total oxy-radical scavenging capacity (TOSC) assay was used to evaluate antioxidant activity of total extracts (T-PG), polysaccharide fraction (Po-PG), and saponin fraction (Sa-PG) isolated from P. grandiflorum against peroxyl radicals and peroxynitrites. And MTT assay was taken to assess cyto-protective effects of T-PG, Po-PG and Sa-PG in H4IIE cells treated with hydrogen peroxide and tert-butylhydroperoxide. In the TOSC assay, Sa-PG showed strong oxy-radical scavenging capacity compared with T-PG and Po-PG. In cell-based assay, T-PG and Po-PG protected cells from oxidative stress, but Sa-PG did not protect cells because of cytotoxicity of Sa-PG. These results suggest that the saponin components of P. grandiflorum have relatively strong antioxidant capacity and cytotoxicity in rat hepatoma cells.

The Effects of Panax ginseng and P. quinquefolium on Hemodynamics and Body Temperature in Healthy Young Men (III)

  • Lee, Jee-Hwan;Cho, Jung-Ah;Ki, Chan-Young;Son, Yeon-Kyoung;Park, Jeong-Hill;Park, Man-Ki;Han, Yong-Nam
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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    • pp.108-108
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    • 2003
  • The current study was performed to observe the effects of Panax ginseng (PG) and P. quinquefolia (PQ) on hemodynamics such as blood flow rate (BF), blood flow velocity (BV), heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP, and body temperature (BT) in healthy young men. After testing equality of variance, Student's t-test using PROC TTEST was examined to. prove statistical differences between control and ginseng conditions at each time point. It was found that the BF data were fluctuated by personal deviation. In order to minimize the deviation, the results obtained for 6 hrs were reconstituted after dividing them into two periods of the first half from 1 to 3 hrs and of the latter half from 3.5 to 6 hrs. And then the reconstitution data and dose-response curves were obtained. Blood flow such as BF and BV shows significant increases both two periods in the dose of PG 2.25 and PG 9.0, whereas significant decrease in the dose of PG 4.5. However, in the PQ groups, the middle dose PQ 4.5 shows the highest significant increase among the three doses. Except for PG 2.25 in HR, other doses show significant decreases both in the first half and latter half. SBP of PQ 9.0 shows only a significant decrease in the first half; on the other hand, in the latter half, PG 4.5, PG 9.0 and PQ 9.0 significantly increase SBP. In addition, DBP of PG 2.25 and PG 4.5 show significant increase in the both periods. In the BT, PQ groups show gradual decrease from PQ 2.25 to PQ 9.0; however, PG groups show differently. PG 4.5 shows significant decrease, but PG 9.0 shows a increase without statistical meanings. In summary, PG is more effective in respect to keeping homeostasis of hemodynamics.

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Pyronine G와 계면활성제 사이의 상호작용에 관한 연구 (Study on the Interaction between Pyronine G and Surfactant)

  • 송기동;김성현;최칠남;이범규;최형기
    • 공업화학
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    • 제8권2호
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    • pp.154-160
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    • 1997
  • Pyronine G(PG)와 계면활성제 사이의 상호작용을 흡수 및 형광 분광학적으로 조사하였다. PG-AOT계 내에서 ${\gamma}$-band의 최적 조건은 S/D(계면활성제의 농도/PG의 농도)의 80 부근에서 가장 좋았으며, 그 이상에서는 stacking 형태가 점차 파괴되는 해리현상이 일어남을 알 수 있었다. 그리고 양이온 및 비이온 계면활성제계들이 첨가되면 PG 단위체의 흡수세기가 증가하였다. 한편, PG-AOT계 내에서 NaCl 농도가 증가함에 따라 S/D<10까지는 ${\gamma}$-band의 흡수세기가 감소하였다. 그러나 S/D>20에서는 흡수세기가 큰 차이를 보이면서 증가하였다. NaCl를 첨가한 PG-AOT계는 NaCl를 첨가하지 않은 계보다 더 큰 해리 현상이 일어남을 알 수 있었다.

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Lyotropic Behaviors of a Phospholipid-based Lamella Liquid Crystalline Phase Hydrated by Propylene Glycol as a Polar Solvent: Correlation of DSPC vs PG Concentration

  • Jeong, Tae-Hwa;Oh, Seong-Geun
    • Bulletin of the Korean Chemical Society
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    • 제28권1호
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    • pp.108-114
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    • 2007
  • The lyotropic behaviors to form the structure of distearoylphosphatidylcholine (DSPC)-based liquid crystal (LC) hydrated by only propylene glycol (PG) without water were examined by differential scanning calorimetry (DSC), X-ray diffractions (XRD), polarized microscope (PM) and transmission electron microscope (TEM). By increasing the amount of PG instead of water, it showed the phase transition to be gradually changed from anisotropic structures to other structures more close to isotropic ones and their appearance to be changed from solid-like states to liquid-like ones with more fluidity. Below 50% w/w PG, the mixtures of DSPC and PG resulted in no direct observation of LC structure through PM because they were very close to solid-states. From 55% w/w to 90% w/w of PG, the dense lamella crystalline structures were observed through PM, and their thickness and area decreased as the content of PG increased. Measured by DSC with heating process, the main phase transition from α -lamella phase to isotropic phase appeared from 52.89 °C to 47.41 °C to show linearly decreasing behaviors because PG affects the hydrophobic region of DSPC-based lamella phase. The repeating distance of the lamella phase and the interlayer distance between bilayers were calculated with XRDs and the average number of bilayers related to the thickness in LC structure was approximately estimated by combining with TEM results. The WAXS and DSC measurements showed that all of PG molecules contributed to swelling both the lipid layer in the edge region of lamella phase close to phosphate groups and the interlayer between bilayers below 90% w/w of PG. The phase and thermal behaviors were found to depend on the amount of PG used by means of dissolving DSPC as a phospholipid and rearranging its structure. Instead of water, the inducement of PG as a polar solvent in solid-lamella phase is discussed in terms of the swelling effect of PG for DSPC-based lamella membrane.

평간개울지혈탕이 독성약물에 의한 간조직 손상에 미치는 영향 (Effect of Pyunggangaeuljihyul-tang (Pinggankaiyuzhixue-tang) on Toxic Agent Induced Liver Cell Damage)

  • 오세광;김원일;김우환
    • 대한한의학회지
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    • 제24권3호
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    • pp.96-107
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    • 2003
  • Objective : This study was undertaken to determine if Pyunggangaeuljihyul-tang (Pinggankaiyuzhixue-tang, PG) has a protective effect against cell injury induced by various toxic agents in rabbit liver, Methods : Cell injury in vitro was estimated by measuring lactate dehydrogenase (LDH), and that in vivo was estimated by measuring alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activity in serum. Lipid peroxidation was examined by measuring malondialdehyde, a product of lipid per oxidation. Results : PG prevented the LDH release by $CCl_4$, mercury, menadione, and tert-butyl hydroperoxide treatment in vitro in liver slices. The extent of protection by 2% PG was similar to that of $10{\mu\textrm{M}}$ N,N'-diphenyl-p-phenylenedianline, a potent antioxidant, in tert-butyl hydroperoxide-induced LDH release. PG also prevented lipid peroxidation and depletion of cellular ATP induced by Hg. Hg causes motphological changes including cell necrosis and its effect was significantly prevented by PG. When rats were treated intraperitoneatly with 0.5 ml/kg of $CCl_4$, serum alanine aminotransferase and aspartate aminotransferase activities were increased compared with the control, which was significantly inhibited by pretreatment of PG. PG also prevented reduction in GSH and lipid peroxidation induced by $CCl_4$ Conclusion : These results suggest that PG exerts aprotective effect against various toxic agents by its antioxidant action in liver tissues. Thus, PG may be used in prevention and treatment of drug-induced liver cell injury. However, the precise mechanisms of PG protection remain to be determined.

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부산석고 시용에 의한 밭 토양 특성과 마늘의 수량 및 품질에 미치는 영향 (Effects of Phosphogypsum Application on Field Soil Properties and Yield and Quality of Garlic (Allium sativum L.))

  • 김영남;조주영;윤영은;최현지;정미선;이미나;김권래;이용복
    • 한국환경농학회지
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    • 제40권1호
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    • pp.33-39
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    • 2021
  • BACKGROUND: Globally, large amounts of phosphogypsum (PG), which is a by-product of the phosphate fertilizer production, is deposited in open areas. As PG contains calcium, phosphate, and sulphate, it can be used as a soil amendment in farmlands. This study was conducted to investigate the effects of PG application on properties of field soil and yield and quality of garlic (Allium sativum L.), and to seek appropriate level of PG application into the field. METHODS AND RESULTS: This experiment was conducted by applying PG at four different levels that were adjusted based on 65% calcium base saturation in the field soil: 0% (control), 50% (PG50, 100 kg/10a), 100% (PG100, 200 kg/10a), and 150% (PG150, 300 kg/10a). Following cultivation, soil electrical conductivity (EC), organic matter, available P and exchangeable Ca increased, whilst soil pH decreased. With increase in PG application level, soil EC and exchangeable Ca increased. PG application increased concentrations of water soluble Ca and SO4 across the soil profile, especially in PG150. The highest yield of garlic was found in PG100 treatment. The plant's uptake for N, P, Ca, and S increased by PG applications, but that for K decreased. Moreover, concentrations of S-related amino acids such as cysteine and methionine in garlic increased by PG applications. The increased content of nutrients and amino acids with PG supply might improve yield, quality, and favor of the crop. CONCLUSION: Overall, PG application at 200 kg/10a into a field had the best effect on improving soil fertility as well as yield and quality of garlic. Further studies are required to maximize efficiencies of PG supply in soil management and production of various crops.