• YAKHAK HOEJI
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• v.50 no.1
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• pp.8-14
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• 2006

A 1 : 1 mixture of acriflavine (ACF; CAS 8063-24-9) and guanosine is currently being evaluated as a possible antitumor agent in preclinical studies. Guanosine is known to potentiate the anticancer activity of some compounds. However, the distributions of trypaflavine (TRF) or proflavine (PRF) have not been investigated in mammals. We, therefore, investigated the distribution of TRF and PRF after i.m. administration of the combination mixture (ACF and guanosine) at a dose of 30 mg/kg ACF in rats. to analyze TRF and PRF levels in biological samples, we used an HPLC-based method. The calibration curves for TRF and PRF in the samples were linear over the concenration range of $0.05{\sim}200\;{\mu}g/ml$. The intra- and inter-day assay accuracies of this method were within ${\pm}15\%$ of norminal values and the precision did not exceed $15\%$ of relative standard diviation. The lower limits of quantitation were 50 ng/ml for both TRF and PRF. The distribution of TRF or PRF was determined by 48 h after i.m. administration of the combination mixture at a dose of 30 mg/kg ACF. TRF and PRF were distributed as the following order; kidney>lung>liver>small intestine>muscle. Of the various tissues, TRF and PRF were mainly distributed to the kidney and lung. The concentrations of TRF or PRF in the tissues 24 h after i.m. administration decreased to undetectable levels. The concentrations of TRF or PRF in the blood cells were comparable to those for the plasma. However, the concentrations of TRF or PRF in the both plasma and blood cells 12 h after i.m. administration were not detected. The number of the platelets in the 1 ml of the blood was calculated to be $0.183{\times}10^8/ml$ of blood. The PRF concentration in platelets was higher than that of TRF at initial times after i.m. administration of the combination mixture. However, both the TRF and PRF concentrations in the plateles 24 h after i.m. administration of the combination mixture were below the quantifiable limit. In conclusion, the concentrations of TRF or PRF in the various tissues, plasma, blood cells, and plateles decreased to undetectable levels 24 h after i.m. administration of the combination mixture at a dose of 30 mg/kg ACF.

• Journal of Life Science
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• v.30 no.12
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• pp.1118-1127
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• 2020

Alzheimer's disease causes progressive neuronal loss that leads to cognitive disturbances. It is not currently curable, and there is no way to stop its progression. However, since medical treatment for Alzheimer's disease is most effective in the early stages, early detection can provide the best chance for symptom management. Biomarkers for the diagnosis of Alzheimer's disease include amyloid β (Aβ) deposition, pathologic tau, and neurodegeneration. Aβ deposition and phosphorylated tau can be detected by cerebrospinal fluid (CSF) analysis or positron emission tomography (PET). However, CSF sampling is quite invasive, and PET analysis needs specialized and expensive equipment. During the last decades, blood-based biomarker analysis has been studied to develop fast and minimally invasive biomarker analysis method. And one of the remarkable findings is the involvement of platelets as a primary source of Aβ in plasma. Aβ can be transported across the blood - brain barrier, creating an equilibrium of Aβ levels between the brain and blood under normal condition. Interestingly, a number of clinical studies have unequivocally demonstrated that plasma Aβ42/Aβ40 ratios are reduced in mild cognitive impairment and Alzheimer's disease. Together, these recent findings may lead to the development of a fast and minimally invasive early diagnostic approach to Alzheimer's disease. In this review, we summarize recent advances in the biomarkers of Alzheimer's disease, especially the involvement of platelets as a source of peripheral Aβ production and its potential as a blood-based biomarker.

• Korean Journal of Materials Research
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• v.15 no.8
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• pp.521-527
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• 2005

Surface modification of polypropylene hollow fiber membranes was peformed in order to develop blood-compatible biomaterials for use in the blood contacting and oxygenation membranes of a lung-assist device(LAD). Blood compatibility was determined by using anticoagulation blood and evaluating formation of blood clots on their surfaces as well as activation of plasma coagulation cascade, platelet adhesion, and aggregation. It was verified that the number of platelets on the silicone coated fibers was significantly lower than those on polypropylene. It was also found that the polypropylene hollow fiber membranes using plasma treatment exhibited suppression of complement activation in blood compatibility test.

• Archives of Plastic Surgery
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• v.33 no.2
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• pp.198-204
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• 2006

Many clinical trials have shown the effectiveness of the platelet releasate or the platelet gel on chronic wounds. However, the patient's own blood had to be aspirated and processed to make the platelet releasate or a platelet gel. The purpose of this study was to assess the effects of platelet concentrates from the blood bank for the treatment of diabetic foot ulcers. To obtain the basic data of the PDGF-BB content in platelet concentrates supplied from the blood bank, enzyme-linked immunosorbent assay quantification was performed. On average, 8.5 pg of the PDGF-BB was released per 1 million platelets. Sixteen patients with diabetic foot ulcers ranging from 1.0 to $18.0cm^2$(mean, $6.1cm^2$) in size were treated. The platelet concentrates was centrifuged and the precipitantte was mixed with 1 ml of fibrinogen. The platelets and fibrinogen mixture was dispersed on to the ulcer lesions. The liquid platelet and fibrinogen mixture was then sealed using 0.3-1.0 ml of thrombin and moisture dressing was performed. The procedure was repeated every one or two weeks until wound closure. Time required for complete healing ranged from 3 to 12 weeks after treatment (mean, 7.3 weeks). Patient satisfaction was also very positive. In this study, the use of platelet concentrates from the blood bank was found to be effective in treating diabetic foot ulcers.

• Journal of Veterinary Clinics
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• v.15 no.2
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• pp.346-351
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• 1998

As an antitumor agents cyclophosphamide (CPA) is frequently used in animal clinic. Important adverse effects of its administration are leukopenia, thrombocytopenia and anemia. We investigated the effects of chicken egg white derivatives (EWD and EF-203) on the changes of blood cells and the neutrophil phagocytosis of rats administered with CPA. Rats were administered CPA peritoneally at dose of 50 mgag once a day far 3 days plus either EWD or EF-203 orally at dose of 200 mg/kg once a day far 3 days. Thereafterl the changes of blood cells by automatic blood cell counter and the phagocytosis of neutrophils by flow cytometry were examined far 7 days. There was no change in RBC values regardless of administration of either EWD or EF-203 throughout experimental period. But rats receiving CPA plus either EWD or EF-203 showed a significant higher PCV values than those of CPA alone (p<0.01). The numbers of peripheral blood platelets and WBC and the differential count of neutrophils in the ra% receiving CPA plus either EWD or EF-203 were significantly higher (p<0.05 to 0.01) than those of CPA alone. Moreover, these rats showed significanly enhanced phagocytoses of neutrophils when compared to rats with CPA alone (p<0.01). These result suggested that chicken egg white derivatives including EWD and EF-2% have immunomodulatory effects in regard to the increase of platelets, WBC, differential count of neutrophils, PCV, and the enhancement of phagocytic activity of neutrophils in immunosuppressed rats by CPA. Thus, co-adminstration of chicken egg white derivatives will be able to reduce the side effects in the animals treated with antitumor agents.

• The Journal of Korean Medicine
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• v.25 no.1
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• pp.21-30
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• 2004

Objectives : We aimed to identify the effects of Heechum-san(HCS) On the thrombosis. Methods : We measured the protective effects of HCS on pulmonary thromboembolism induced by collagen and epinephrine, intravascular coagulation induced by dextran. Results : HCS showed a effective inhibition on coagulation of platelets induced by ADP or epinephrine. HCS showed survival rate of 14.28% on pulmonary thrombo- embolism caused by collagen and epinephrine. On the measure of the blood flow rate induced by the thrombus, in vivo HCS accelerated the blood flow rate. Conclusions : HCS has antithrombotic effects.

• Journal of radiological science and technology
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• v.33 no.3
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• pp.185-192
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• 2010

Platelets originating from Megakaryocyte are sensitive to radiation along with white blood cells, and thus these platelets are used as an index of radiation hazard as they decrease in advance. Thus, when there is a scarcity of platelets, dot hemorrhage occurs and it leads to decrease of blood corpuscle and a decline in immunity. In particular, when 4~6 Gy whole body irradiation is received, after three weeks, the platelets will decrease to the lowest level, which can be a cause of death by bleeding and anemia. Therefore, this study tried to identify the mechanism of platelet damage and protection effect. The protection substance used in the experiment is Alliin, which is a component of garlic, and it was observed by an Transmission Electron Microscope(TEM) after its injection to the rat's tail vein. In the study, it was found that the cell membrane was severely damaged in a 10-day progressed platelet organ after receiving 5 Gy irradiation. It billowed as balloon-like figure and the glycocalyx became hyperplasia. The minute organ was damaged to the point that it was beyond recognition in a 20-day progressed platelet organ after receiving irradiation, and the cytoplasmic contents were exposed to epilepsy parts and outrageously damaged. Furthermore, the form of granules could also not be observed. A hole was formed in the middle, and the damaged organ was found in a 30-day progressed platelet. However, the form of granules was consistently maintained in the experiment group injecting Alliin, as with the control group, and there was no damage to the cell membrane recognized. Thus, it was possible to verify the effectiveness of radiation protection of the platelet when Alliin was injected to the blood vessel.

• Biomolecules & Therapeutics
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• v.22 no.3
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• pp.254-259
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• 2014

The pentacyclic triterpenoid ursolic acid (UA) and its isomer oleanolic acid (OA) are ubiquitous in food and plant medicine, and thus are easily exposed to the population through natural contact or intentional use. Although they have diverse health benefits, reported cardiovascular protective activity is contentious. In this study, the effect of UA and OA on platelet aggregation was examined on the basis that alteration of platelet activity is a potential process contributing to cardiovascular events. Treatment of UA enhanced platelet aggregation induced by thrombin or ADP, which was concentration-dependent in a range of $5-50{\mu}M$. Quite comparable results were obtained with OA, in which OA-treated platelets also exhibited an exaggerated response to either thrombin or ADP. UA treatment potentiated aggregation of whole blood, while OA failed to increase aggregation by thrombin. UA and OA did not affect plasma coagulation assessed by measuring prothrombin time and activated partial thromboplastin time. These results indicate that both UA and OA are capable of making platelets susceptible to aggregatory stimuli, and platelets rather than clotting factors are the primary target of them in proaggregatory activity. These compounds need to be used with caution, especially in the population with a predisposition to cardiovascular events.

• Clinical and Experimental Pediatrics
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• v.65 no.4
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• pp.182-187
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• 2022

We frequently encounter newborn infants with thrombocytosis in the neonatal intensive care unit. However, neonatal thrombocytosis is not yet fully understood. Thrombocytosis is more frequently identified in newborns and young infants, notably more often in those younger than 2 years than in older children or adults. The production of megakaryocytes (megakaryopoiesis) and platelets (thrombopoiesis) is mainly regulated by thrombopoietin (TPO). Increased TPO levels during infection or inflammation can stimulate megakaryopoiesis, resulting in thrombopoiesis. TPO concentrations are higher in newborn infants than in adults. Levels increase after birth, peak on the second day after birth, and start decreasing at 1 month of age. Initial platelet counts at birth increase with gestational age. Thus, preterm infants have lower initial platelet counts at birth than late-preterm or term infants. Postnatal thrombocytosis is more frequently observed in preterm infants than in term infants. A high TPO concentration and low TPO receptor expression on platelets leading to elevated plasma-free TPO, increased sensitivity of megakaryocyte precursor cells to TPO, a decreased red blood cell count, and immaturity of platelet regulation are speculated to induce thrombocytosis in preterm infants. Thrombocytosis in newborn infants is considered a reactive process (secondary thrombocytosis) following infection, acute/chronic inflammation, or anemia. Thrombocytosis in newborn infants is benign, resolves spontaneously, and, unlike in adults, is rarely associated with hemorrhagic and thromboembolic complications.

• Journal of Nutrition and Health
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• v.26 no.7
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• pp.839-850
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• 1993

This study investigated the hypolipidemic and antithrombotic effects of linolenic acid derived from Korean perilla oil. The experimental rats(male, Sprague-Dawley) were divided into 5 groups using a Randomized Complete Block Design and fed one of the five following diets : DO*/O#. D4/O, D4/4, D4/8, or D4/20(D*/# represents the ratio of linoleic to linoenic acid as the percentage of total dietary energy intake) for 4 or 8 months. Bleeding time and whole blood clotting time were determined and the composition of serum and platelet lipids analyzed. Comparisons from the DO/O to the D4/20 group showed that serum lipids (total lipid, triglyceride, total cholesterol, and HDL-cholesterol) gradually decreased with increasing linolenic acid intake - the hypolipidemic effect. The composition of platelet fatty acids[the ratio of eicosapentaenoic acid(EPA)/arachidonci aci(AA)] increased gradually with increasing linolenic acid intake. Higher linolenic acid intake increased bleeding time and whole blood clotting time, and decreased malondialdehyde(MDA) production in the platelets, though no significant differences. These results suggest that linolenic acid derived from perilla oil appears to suppress the conversion of linoleic acid to AA and the EPA transformed from linolenic acid appears to suppress the conversion of AA to TXA2. Since TXA2 is a platelet-aggregating and vasoconstricting agent, the redulction of TXA2 released by platelets with increasing intake of perilla oil containing a lot of linolenic acid confers an antithrombotic effect.