• Title/Summary/Keyword:  PAF

Search Result 172, Processing Time 0.024 seconds

Purification and Identification of a Novel Antifungal Protein Secreted by Penicillium citrinum from the Southwest Indian Ocean

  • Wen, Chao;Guo, Wenbin;Chen, Xinhua
    • Journal of Microbiology and Biotechnology
    • /
    • v.24 no.10
    • /
    • pp.1337-1345
    • /
    • 2014
  • A novel antifungal protein produced by the fungal strain Penicillium citrinum W1, which was isolated from a Southwest Indian Ocean sediment sample, was purified and characterized. The culture supernatant of P. citrinum W1 inhibited the mycelial growth of some plant pathogenic fungi. After saturation of P. citrinum W1 culture supernatants with ammonium sulfate and ion-exchange chromatography, an antifungal protein (PcPAF) was purified. The N-terminal amino acid sequence analysis showed that PcPAF might be an unknown antifungal protein. PcPAF displayed antifungal activity against Trichoderma viride, Fusarium oxysporum, Paecilomyces variotii, and Alternaria longipes at minimum inhibitory concentrations of 1.52, 6.08, 3.04, and $6.08{\mu}g/disc$, respectively. PcPAF possessed high thermostability and had a certain extent of protease and metal ion resistance. The results suggested that PcPAF may represent a novel antifungal protein with potential application in controlling plant pathogenic fungal infection.

Effects of Tetrandrine and Fangchinoline on Human Platelet Aggregation, Thromboxane B$_2$ Formation and Blood coagulation.

  • Zhang, Yong-He;Kim, Hack-Seang;Yun, Yeo-Pyo;Lee, Hyung-Kyu
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 1998.11a
    • /
    • pp.177-177
    • /
    • 1998
  • In the previous report, tetrandrine (TET) and fangchinoline (FAN) showed antithrombotic and antiplatelet aggregation activities. The present study was undertaken to investigate the effects of tetrandrine and fangchinoline on human platelet aggregation, formation of thromboxane B$_2$ and coagulation of platelet poor plasma. TET and FAN inhibited platelet activating factor (PAF) induced human platelet aggregation, but didn't inhibit the specific binding of PAF to its receptor. Meanwhile, TET and FAN also inhibited PAF, thrombin and arachidonic acid induced thromboxane B$_2$ formation in human washed platelets. In addition, neither TET nor FAN showed any anticoagulation activities in the measurement of the activated partial thromboplastin time (APTT), prothrombin time (PT) and thrombin time (TT) using human platelet poor plasma. These results suggest that antithrombotic effects of TET and FAN in mice may be mainly related to the antiplatelet aggregation activities, and the antiplatelet aggregation effects may be related to the intracellular messenger system such as TXA$_2$ formation etc., but not to the binding of PAF to PAF-receptor on the platelet membrane directly.

  • PDF

Fabrication of triazine-based Porous Aromatic Framework (PAF) membrane with structural flexibility for gas mixtures separation

  • Wang, Lei;Jia, Jiangtao;Faheem, Muhammad;Tian, Yuyang;Zhu, Guangshan
    • Journal of Industrial and Engineering Chemistry
    • /
    • v.67
    • /
    • pp.373-379
    • /
    • 2018
  • A transparent, freestanding Porous Aromatic Framework-97 (PAF-97) membrane was successfully synthesized via a one-step acid-catalyzed reaction. Due to the introduction of ether groups, the obtained PAF-97 membrane possesses enhanced structural flexibility, thus increasing the flexibility of the resulting membrane. This is proofed by the fact that the feeding pressure of the membrane reaches as high as 5.5 bar during the separation of gas mixtures. The Young's moduli of the membrane were 6.615 GPa and 11.11 GPa, either in a dry or hydrated state respectively. To be highlighted, under a feeding pressure of 3.6 bar, the PAF-97 membrane rendered the permeance values of $2.90{\times}10^{-7}$, $1.29{\times}10^{-8}mol\;m^{-2}s^{-1}Pa^{-1}$ for $CO_2$ and $CH_4$, respectively, with a $CO_2/CH_4$ permselectivity of 22.48.

Prediction of Paroxysmal Atrial Fibrillation using Time-domain Analysis and Random Forest

  • Lee, Seung-Hwan;Kang, Dong-Won;Lee, Kyoung-Joung
    • Journal of Biomedical Engineering Research
    • /
    • v.39 no.2
    • /
    • pp.69-79
    • /
    • 2018
  • The present study proposes an algorithm that can discriminate between normal subjects and paroxysmal atrial fibrillation (PAF) patients, which is conducted using electrocardiogram (ECG) without PAF events. For this, time-domain features and random forest classifier are used. Time-domain features are obtained from Poincare plot, Lorenz plot of ${\delta}RR$ interval, and morphology analysis. Afterward, three features are selected in total through feature selection. PAF patients and normal subjects are classified using random forest. The classification result showed that sensitivity and specificity were 81.82% and 95.24% respectively, the positive predictive value and negative predictive value were 96.43% and 76.92% respectively, and accuracy was 87.04%. The proposed algorithm had an advantage in terms of the computation requirement compared to existing algorithm, so it has suggested applicability in the more efficient prediction of PAF.

Synthesis of Substituted Cinnamoyl-tyramine Derivatives and their platelet Anti-aggregatory Activities

  • Woo, Nam-Tae;Jin, Sun-Yong;Cho, Jin-Cho;Kim, Nam-Sun;Bae, Bae-Eun-Hyung;Han, Ducky;Han, Byung-Hoon;Kang, Young-Hwa
    • Archives of Pharmacal Research
    • /
    • v.20 no.1
    • /
    • pp.80-84
    • /
    • 1997
  • Substituted cinnamoyl-tyramine derivatives were synthesized by DCC-coupling of substituted cinnamic acid with tyramine or tyramine methyl-1-ether to evaluate PAF-receptor binding antagonistic activities and inhibitory activities on PAF-induced platelet aggregation with interest on structure-activity relations. The results show that 3,4-dimethoxy-cinnamoyl tyramine-amide or its methyl ether have significant PAF-receptor binding antagonistic activity and platelet anti-aggregatory activities.

  • PDF

Partial Purification and Characterization of PAF Acetylhydrolase in Human Amniotic Fluid

  • Son, So-Young;Kim, So-Hee;Baek, Suk-Hwan;Chang, Hyeun-Wook
    • Archives of Pharmacal Research
    • /
    • v.20 no.3
    • /
    • pp.218-224
    • /
    • 1997
  • Platelet-activating factor (PAF) acetylhydrolase, which removes the acetyl moiety at the sn-2 position, has been found in human amniotic fluid. We purified this enzyme by ammonium sulfate precipitation, and sequential use of DEAE-Sepharose CL-6B, hydroxyapatite, chelating-Sepharose, and Mono Q column chromatographies. This enzyme exhibited broad pH optima and was unaffected by EDTA. Partially purified enzyme had a molecular weight of approximately 34 kDa on SDS-PAGE. In addition, the enzyme activity was inhibited by either diisopropylfluorophosphate(DFP) or p-bromophenacylbromide (p-BPB), suggesting that this enzyme possesses active serine and histidine residues. The enzyme showed similar activity towards PAF and oxidatively modified phosphatidylcholine, but didn't hydrolyze phosphatidylcholine or phosphatidylethanolamine with a long chain fatty acyl group at sn-2 position.

  • PDF

Screening of the Inhibiory Effects of Herbal Medicines on the Platelet Activating Facthr(PAP) Binding : Randomly Selected Herbal Medicines (생약 물 추출물의 혈소판 활성화 인자결합 억제효과 검색 : 무작위로 선정한 국내 유통 생약)

  • 한병훈;양현옥;이승룡;조순현;고현정;한용남
    • YAKHAK HOEJI
    • /
    • v.39 no.1
    • /
    • pp.1-5
    • /
    • 1995
  • As a continuation of the previous study, a second group of sixty two aqueous extracts(freeze dried) from natural products was screened for the inhibitory effect of platelet activating factor(PAF) binding to rabbit platelet using 0.6 nM [$^{3}$H]PAF as a radioligand. The results demonstrated that three medicinal plants inhibited 40~50% of [$^{3}$H]PAF equilibrium binding at the concentration of 200 $\mu\textrm{g}$/ml.

  • PDF

Screening of Arachidonic Acid Cascade Related Enzymes Inhibitors from Korean Indigenous Plants (2) (한국 자생식물로부터 아라키돈산 대사계 효소 저해제 검색 (2))

  • 정혜진;문태철;이은경;손건호;김현표;강삼식;배기환;안인파;권동렬
    • YAKHAK HOEJI
    • /
    • v.47 no.2
    • /
    • pp.69-77
    • /
    • 2003
  • Arachidonic acid (AA), which is stored in membrane glycerophospholipids, is liberated by phospholipase $A_2$ (PLA$_2$) enzymes and is sequentially converted to cyclooxygenases (COXs) and lipoxygenases (LOXs) then to various bioactive PGs, and LTs. In order to find the specific inhibitors of AA metabolism especially PLA$_2$, COX-2, 5-LO and lyso PAF acetyltransferase, 120 Korean residential plants extracts were evaluated for their inhibitory activity on PGD$_2$, LTC$_4$ production from cytokine-induced mouse bone marrow-derived mast cells (BMMC) and arachidonic acid released from phospholipid and PAF production from lyso PAF. From this screening procedure, methanol extract of ten indigenous plant such as Salix gracilistyla, Sedum kamtschaticum, Cirsium chanroenicum, Hypericum ascyron, Astilbe chinensis, Agrimonia pilosa, Aristolochia manshuriensis, Vodia daniellii, Pyrola japonica, Styrax obassia were found to inhibit production of inflammatory mediators in vitro assay system.

Impact Properties of Organic Fiber Reinforced Thermoplastic Composites (유기섬유강화 열가소성고분자 복합재료의 충격특성)

  • Im, Seung-Soon;Lee, Seung-Bae;Lee, Yong-Moo;Choi, Hyeong-Ki
    • Applied Chemistry for Engineering
    • /
    • v.7 no.3
    • /
    • pp.424-432
    • /
    • 1996
  • The fiber reinforced thermoplastic composites(FRTP) were prepared with polypropylene fiber(PPF) as matrix and vinylon(VF), Aramid(KF) or nylon fiber(PAF) as reinforcing materials using the integrated fiber mixing apparatus. The composite sheets were prepared by compression molding and their impact and morphological properties were characterized. VF/PP system showed the maximum value in Izod impact strength, while KF/PP system showed the maximum value in high rate impact properties. Ductility Index(DI) order was VF/PP>KF/PP>PAF/PP. A maximum DI for VF/PP, 2.43, was obtained when the weight fraction of VF was 20%. The optimum amount of the reinforcing organic fiber was found to be 20~30%. As a result, it is concluded that VF/PP system has better interfacial adhesion properties than either KF/PP or PAF/PP.

  • PDF

Rheological Properties of Organic Fiber-Reinforced Thermoplastics (유기섬유 강화 열가소성 복합재료의 유변학적 특성)

  • Lee, Yong-Mu;Cha, Yun-Jong;Kim, Seong-Hyeon;Yun, Yeo-Seong;Yun, Ju-Ho;Choe, Hyeong-Gi
    • Korean Journal of Materials Research
    • /
    • v.6 no.8
    • /
    • pp.786-795
    • /
    • 1996
  • The fiber reinforced thermoplastics(FRTP) were prepared with polypropylene fiber(PP) as matrix and polyvinyl alchol(VF), aramid(KF) or polyamide fiber(PAF) as the reinforcing materials using the integrated fiber mixing apparatus. The reinforced thermoplastic sheets were prepared by com¬pression molding and their morphology, rheological and mechanical properties were characterized. In the morphological properties of composites, the wettability of the reinforced thermoplastics were decreased in proportion to the content of fibers. At low angular frequency, the viscosity of PAF /PP and VF/PP composite was increased with the content of reinforced fiber. However at high frequency the viscosity of composite reinforced with 5~20wt% fiber, was shown the reduced values which approaches that of the neat matrix. The mechanical properties of the composite were changed with the content of reinforecd fiber, and VF/PP and KF/PP composite had better properties than PAF/PP system.

  • PDF