• Title/Summary/Keyword: Group Aggregation

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Screening of Potential Inhibitors of Platelet Aggregation from Plant Sources(II) (혈소판 응집 억제 작용 생약의 검색(II))

  • YunChoi, Hye-Sook;Kim, Jae-Hoon;Lee, Jong-Ran
    • Korean Journal of Pharmacognosy
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    • v.17 no.1
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    • pp.19-22
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    • 1986
  • As a continuation of the previous work, a second group of sixty solvent fractions prepared from twenty plant species were screened for their inhibitory effects on adenosine 5'-diphosphate (ADP)-, arachidonic acid (AA)- or collagen-induced rat platelet aggregation. The results suggested that five plant species including Angelica koreana, Cassia obtusifolia, Gastrodia elata, Paeonia lactiflora and Salvia miltiorrhiza are potential sources of inhibitors of platelet aggregation.

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Oxidative Modification of Neurofilament-L by the Cytochrome c and Hydrogen Peroxide System

  • Kang, Jung-Hoon
    • Bulletin of the Korean Chemical Society
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    • v.28 no.1
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    • pp.77-80
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    • 2007
  • As neurofilament proteins are major cytoskeletal components of neuron, abnormality of neurofilament is proposed in brain with neurodegenerative disorders such as Parkinson's disease (PD). Since oxidative stress might play a critical role in altering normal brain proteins, we investigated the oxidative modification of neurofilament-L (NF-L) induced by the reaction of cytochrome c with H2O2. When NF-L was incubated with cytochrome c and H2O2, the protein aggregation was increased in cytochrome c and H2O2 concentrationsdependent manner. Radical scavengers, azide, formate and N-acetyl cysteine, prevented the aggregation of NFL induced by the cytochrome c/H2O2 system. The formations of carbonyl group and dityrosine were obtained in cytochrome c/H2O2-mediated NF-L aggregates. Iron specific chelator, desferoxamine, prevented the cytochrome c/H2O2 system-mediated NF-L aggregation. These results suggest that the cytochrome c/H2O2 system may be related to abnormal aggregation of NF-L which may be involved in the pathogenesis of PD and related disorders.

The Dry-aging and Heating Effects on Protein Characteristics of Beef Longissiumus Dorsi

  • Kim, Ji-Han;Lee, Ha-Jung;Shin, Dong-Min;Kim, Tae-Kyung;Kim, Young-Boong;Choi, Yun-Sang
    • Food Science of Animal Resources
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    • v.38 no.5
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    • pp.1101-1108
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    • 2018
  • The aim of this study was to investigate the effects of dry-aging (DA) and the cooking process on the myofibril protein functionalities and in vitro digestibility of proteins in beef loin. Six sirloins from beef were dry-aged for 28 d, and the control group (n=6) was analyzed 2 d postmortem for this study. Dimensional changes (reduction of thickness and surface shrinkage) after cooking were significantly greater in the control group than the DA group, whereas the shear force of the DA group was significantly lower than that of the control. Effect of cooking on aggregation, hydrophobicity, and in vitro digestibility were significantly higher in the DA group than in the control. After cooking, the protein in DA sirloins was more oxidized than in the control samples. According to the sodium dodecyl sulfate-polyacrylamide gel electrophoresis result, the low molecular weight bands (below 17 kDa) increased in the DA group, finding that the protein characteristics of dry-aged beef was affected by cooking.

Effects of Horsetail, Alfalfa, Ortie, Chêne and Aleppo oak as Potential Hemostatic Agents on Laboratory Coagulation Tests

  • Sina Ahmadianfar;Nahid Mehrabi;Saeed Mohammadi;Ali Sobhanizadeh;Alireza Moradabadi;Ali Noroozi-Aghideh
    • Natural Product Sciences
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    • v.29 no.1
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    • pp.42-49
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    • 2023
  • This study investigated the effect of ethanol extracts of horsetail, alfalfa, ortie, chêne and aleppo oak on blood coagulation in vitro. Extraction was performed by the maceration method. Extracts were mixed with platelet and plasma, then prothrombin time (PT), activated partial thromboplastin time (APTT) and platelet aggregation tests were conducted. Alfalfa extract had a dose-dependent effect on the PT. Ortie, and horsetail, reduced the PT significantly compared to control group. Alfalfa, horsetail, and ortie reduced the APTT, but their effect was insignificant compared to the control group. The pooled extract showed the highest effect compared to the single extracts in a dose-dependent manner. Horsetail and alfalfa induced platelet aggregation in response to arachidonic acid but not in response to collagen. In the case of ortie, no aggregation occurred regarding the arachidonic acid, and incomplete was observed in response to collagen. Interestingly, blood clotting occurred immediately after adding the chêne, aleppo oak and the pooled extract, and therefore platelet poor plasma (PPP) and platelet rich plasma (PRP) became jelly. Generally, chêne and aleppo oak, as well as pooled extract, were more effective in inducing both primary and secondary coagulation pathways via shortening the PT and APTT, and induction of platelet aggregation.

An Induced Hesitant Linguistic Aggregation Operator and Its Application for Creating Fuzzy Ontology

  • Kong, Mingming;Ren, Fangling;Park, Doo-Soon;Hao, Fei;Pei, Zheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.10
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    • pp.4952-4975
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    • 2018
  • An induced hesitant linguistic aggregation operator is investigated in the paper, in which, hesitant fuzzy linguistic evaluation values are associated with probabilistic information. To deal with these hesitant fuzzy linguistic information, an induced hesitant fuzzy linguistic probabilistic ordered weighted averaging (IHFLPOWA) operator is proposed, monotonicity, boundary and idempotency of IHFLPOWA are proved. Then andness, orness and the entropy of dispersion of IHFLPOWA are analyzed, which are used to characterize the weighting vector of the operator, these properties show that IHFLPOWA is extensions of the induced linguistic ordered weighted averaging operator and linguistic probabilistic aggregation operator. In this paper, IHFLPOWA is utilized to gather linguistic information and create fuzzy ontologies, and a movie fuzzy ontology as an illustrative case study is used to show the elaboration of the proposed method and comparison with the existing linguistic aggregation operators, it seems that the IHFLPOWA operator is an useful and alternative operator for dealing with hesitant fuzzy linguistic information with probabilistic information.

Effects of green tea or $Sasa$ $quelpaertensis$ bamboo leaves on plasma and liver lipids, erythrocyte Na efflux, and platelet aggregation in ovariectomized rats

  • Ryou, Sung-Hee;Kang, Min-Sook;Kim, Kyu-Il;Kang, Young-Hee;Kang, Jung-Sook
    • Nutrition Research and Practice
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    • v.6 no.2
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    • pp.106-112
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    • 2012
  • This study was conducted to investigate the effects of $Sasa$ $quelpaertensis$ bamboo and green tea on plasma and liver lipids, platelet aggregation, and erythrocyte membrane Na channels in ovariectomized (OVX) rats. Thirty female rats were OVX, and ten female rats were sham-operated at the age of 6 weeks. The rats were divided into four groups at the age of 10 weeks and fed the experiment diets: sham-control, OVX-control, OVX-bamboo leaves (10%), or OVX-green tea leaves (10%) for four weeks. Final body weight increased significantly in the OVX groups compared with that in the sham-control, whereas body weight in the OVX-green tea group decreased significantly compared with that in the OVX-control ($P$ < 0.01). High density lipoprotein (HDL)-cholesterol level decreased in all OVX groups compared with that in the sham-control rats ($P$ < 0.05) but without a difference in plasma total cholesterol. Plasma triglycerides in the OVX-green tea group were significantly lower than those in the sham-control or OVX-control group ($P$ < 0.05). Liver triglycerides increased significantly in the OVX-control compared with those in the sham-control ($P$ < 0.01) but decreased significantly in the OVX-green tea group compared with those in the OVX-control or OVX-bamboo group ($P$ < 0.01). Platelet aggregation in both maximum and initial slope tended to be lower in all OVX rats compared with that in the sham-control rats but was not significantly different. Na-K ATPase tended to increase and Na-K cotransport tended to decrease following ovariectomy. Na-K ATPase decreased significantly in the OVX-green tea group compared with that in the OVX-control group ($P$ < 0.01), and Na-K cotransport increased significantly in the OVX-bamboo and OVX-green tea groups compared with that in the OVX-control ($P$ < 0.05). Femoral bone mineral density tended to be lower in OVX rats than that in the sham-control, whereas the green tea and bamboo leaves groups recovered bone density to some extent. The results show that ovariectomy caused an increase in body weight and liver triglycerides, and that green tea was effective for lowering body weight and triglycerides in OVX rats. Ovariectomy induced an increase in Na efflux via Na-K ATPase and a decrease in Na efflux via Na-K cotransport. Furthermore, consumption of green tea and bamboo leaves affected Na efflux channels, controlling electrolyte and body water balance.

Priority Aggregation for AHP Based on Experts Opinions (AHP 가중치 결정에서의 다수 전문가 의견종합 방법)

  • 김성철;어하준
    • Journal of the Korean Operations Research and Management Science Society
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    • v.19 no.3
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    • pp.41-51
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    • 1994
  • The Analytic Hierarchy Process (AHP) is widely used for evaluation of large projects. If a group of experts with different expertise are involved in a AHP decision, they need some way to aggregate their opinions. In this paper, we suggest a way to aggregate the experts' priorities in a given hierarchy using the concept of the Bayesian decision analysis. A criterion that can be used for screening out unreliable data is introduced, and it is used for priority aggregation. Some numerical results are shown to illustrate the procedure.

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Aggregation of Human Eyelid Adipose-derived Stem Cells by Human Body Fluids

  • Song, Yeonhwa;Yun, Sujin;Yang, Hye Jin;Yoon, A Young;Kim, Haekwon
    • Development and Reproduction
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    • v.16 no.4
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    • pp.339-351
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    • 2012
  • Fetal bovine serum (FBS) is the most frequently used serum for the cultivation of mammalian cells. However, since animal-derived materials might not be appropriate due to safety issues, allogeneic human serum (HS) has been used to replace FBS, particularly for the culture of human cells. While there has been a debate about the advantages of HS, its precise effect on human adult stem cells have not been clarified. The present study aimed to investigate the effect of HS on the human eyelid adipose stem cells (HEACs) in vitro. When HEACs were cultivated in a medium containing 10% HS, many cells moved into several spots and aggregated there. The phenomenon was observed as early as 9 days following 10% HS treatment, and 12 days following 5% HS plus 5% FBS treatment. However, the aggregation was never observed when the same cells were cultivated with 10% FBS or bovine serum albumin. To examine whether cell density might affect the aggregation, cells were seeded with different densities on 12-well dish. Until the beginning of aggregation, cells seeded at low densities exhibited the longest culture period of 16 days whereas cells seeded at high densities showed the shortest period of 9 days to form aggregation. The number of cells was $15.1{\pm}0.2{\times}10^4$ as the least for the low density group, and $29.3{\pm}2.8{\times}10^4$ as the greatest for the high density group. When human cord blood serum or normal bovine serum was examined for the same effect on HEACs, interestingly, cord blood serum induced the aggregation of cells whereas bovine serum treatment has never induced. When cells were cultivated with 10% HS for 9 days, they were obtained and analyzed by RT-PCR. Compared to FBS-cultivated HEACs, HS-cultivated HEACs did not express VIM, and less expressed GATA4, PALLD. On the other hand, HS-cultivated HEACs expressed MAP2 more than FBS-cultivated HEACs. In conclusion, human adult stem cells could move and form aggregates by the treatment with human body fluids.

The Effect of Pulsatile Versus Nonpulsatile Blood Flow on Viscoelasticity and Red Blood Cell Aggregation in Extracorporeal Circulation

  • Ahn, Chi Bum;Kang, Yang Jun;Kim, Myoung Gon;Yang, Sung;Lim, Choon Hak;Son, Ho Sung;Kim, Ji Sung;Lee, So Young;Son, Kuk Hui;Sun, Kyung
    • Journal of Chest Surgery
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    • v.49 no.3
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    • pp.145-150
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    • 2016
  • Background: Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods: Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous $O_2$ saturation, and lactate were measured. Results: The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion: After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow.

Effects of Low- Dose Aprotinin on Open Heart Surgery (개심술에 있어서 Low-Dose Aprotinin의 투여효과)

  • 박남희;최세영
    • Journal of Chest Surgery
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    • v.29 no.9
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    • pp.989-995
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    • 1996
  • Excessive blood loss secondary to cardiopulmonary bypass(CPB) may be encountered after open heart surgery and platelet dysfunction appears to be especially responsible for this problem. To evaluate the effect of low-dose aprotinin during hypothermic CPB on platelet aggregation, anticoagulation and clinical hemostasis,.40 patients undergoing valve replacement using hypothermic CPB procedures were randomized to give either a low dose aprotinin(2$\times$ 106 KIU in the CPB priming sol- ution, n=20) or a placebo(n=20). During postoperative 24 hours, blood and hemoglobin loss were lower in the aprotinin group (225.5 $\pm$ 121.9ml, and 11.3$\pm$2.4g) than the control group(572.2$\pm$)35.5ml and 26.3$\pm$9.8g)(P<0.01). The total blood and hemoglobin loss were lower in the aprotinin group (622.0$\pm$ 186m1 and 14.7$\pm$6.8g) than the con- trol group (102.1 $\pm$483.5ml and 39.7$\pm$ 16.4g) (P<0.01). The amonut of packed red cell needed decreased in the aprotinin group: 197.7$\pm$56.3ml vers s 651.2: 147.5ml (P<0.01). Hemoglobin concentration, platelet counts and fibrinogen checked at fixed times perioperatively did not differ between the two groups. Platelet aggregation was induced by ADP, collagen, epinephrine and ristocetin before and after CPB. Maximum platelet aggregation was significantly reduced after CPB in control group (ranging from -31 % to -58% relative to prebypass values). Significant prolongation of activated clotting time(ACT) after 5 minute and 30 minute of hypothermic CPB were observed: 955.9 $\pm$35.1 and 967.5$\pm$32.7sec versus 743.8 $\pm$ 52.1 and 731.2: 54.6sec (P<0.01). There was no complication associated with aprotinin infusion. These results demonstrate that low-dose aprotinin significantly reduces blood loss and blood requirment and provides improved postoperative hemostasis which might be related to protection of platelet aggregation capacity.

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