• Journal of Korean Neurosurgical Society
• /
• v.48 no.4
• /
• pp.319-324
• /
• 2010

Objective : The aim of this study was to analyze the correlation between thromboembolic complications and anti platelet drugs before and after neurointervention. Methods : Blood samples and radiographic data of patients who received a neurointervention (coil embolization, stent placement or both) were collected prospectively. Rapid platelet function assay-aspirin (RPFA-ASA) was used to calculate aspirin resistance in aspirin reaction units (ARU). For clopidogrel resistance, a P2Y12 assay was used to analyze the percentage of platelet inhibition. ARU > 550 and platelet inhibition < 40% were defined as aspirin and clopidogrel resistance, respectively. Results : Both aspirin and clopidogrel oral pills were administered in fifty-three patients before and after neurointerventional procedures. The mean resistance values of all patients were 484 ARU and < 39%. Ten (17.0%) of 53 patients showed resistance to aspirin with an average of 597 ARU, and 33 (62.3%) of 53 patients showed resistance to clopidogrel with an average of < 26%. Ten patients demonstrated resistance to both drugs, 5 of which suffered a thromboembolic complication after neurointervention (mean values : 640 ARU and platelet inhibition < 23%). Diabetic patients and patients with hypercholesterolemia displayed mean aspirin resistances of 513.7 and 501.8 ARU, and mean clopidogrel resistances of < 33.8% and < 40.7%, respectively. Conclusion : Identifying individuals with poor platelet inhibition using standard regimens is of great clinical importance and may help prevent cerebral ischemic events in the future. Neurointerventional research should focus on ideal doses, timing, choices, safety, and reliable measurements of anti platelet drug therapy, as well as confirming the clinical relevance of aggregometry in cerebrovascular patients.

• Clinical and Experimental Reproductive Medicine
• /
• v.41 no.2
• /
• pp.92-95
• /
• 2014

Objective: This study sought to evaluate platelet volume indices (mean platelet volume [MPV], platelet distribution width [PDW], and platelet large cell ratio [P-LCR]) in varicocele patients, and compare it with platelet volume parameters in healthy controls. Methods: This cross-sectional study involved 2 groups: group 1 included 51 varicocele subjects and group 2 consisted of 50 healthy control subjects of similar ages. Peripheral venous blood samples were collected with ethylenediaminetetraacetic acid-K2 anticoagulant between 8:30 AM and 10 AM following an overnight fast. Platelet volume parameters (MPV, PDW, and P-LCR) were measured in both groups within 2 hours of sampling. Results: The mean PDW, MPV, and P-LCR were $13.9{\pm}2.5%$, $10.1{\pm}1.3fL$, and $27.3{\pm}7.8%$ in varicocele patients, respectively, and were $12.6{\pm}2.4%$, $9.3{\pm}1.1fL$, and $21.9{\pm}6.4%$ in the control group, respectively. The mean PDW, MPV, and P-LCR were significantly higher in the varicocele group than the control group. Conclusion: The results of the present study suggest that vascular components may play an important role in the pathophysiology of varicocele; therefore, there is a great need for prospective studies to confirm this relationship.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.13
• /
• pp.5537-5540
• /
• 2015

Purpose: To research the association between pre-treatment elevated platelet count and clinicopathologic characteristics in breast cancer (BC), as well as explore the relationship between pre-treatment elevated platelet count and HER2 status and prognosis of BC patients. Materials and Methods: A retrospective cohort of BC patients who were newly diagnosed or treated by surgery only and had pathological detection results and platelet values in the Department of Oncology, the First Affiliated Hospital of Liaoning Medical College were enrolled from 1/1/2008 until 31/12/2009, and followed up until 31/12/2014. Age, thrombocyte parameters before chemotherapy and/or radiotherapy, immunohistochemical (IHM) indexes, and regional lymph node (LN) involvement and progression-free survival (PFS) were recorded. Results: A total of 447 eligible subjects were included in this research. As we analyzed, for HER2, positive and negative, the incidence rates of elevated platelet count were 25.8% and 14.7% (P<0.05). In the Cox proportional hazards model both variables were independent risk factors for BC (for HER2, OR, 0.592, 95% confidence interval, CI, 0.355 to 0.985, P=0.044;f or PLT, OR, 0.998, 95% CI, 0.996 to 1.000, P=0.042). For ER, PR, Ki67 and LN involvement, the differences were not statistically significant (P>0.05). Conclusions: In this research, pre-treatment elevated level of platelet count demostrated a significantrelationship with HER2 amplification/overexpression, and both variables significantly influenced the prognosis of BC. However, elevated platelet count did not exhibit any association with ER, PR, Ki67 and LN involvement.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.25 no.3
• /
• pp.546-550
• /
• 2011

The aim of this study was to evaluate oriental medicine pattern identification in patients with stroke on the basis of plasma fibrinogen levels and platelet counts. 555 patients diagnosed with stroke between November 2006 and February 2010 were divided in several ways according to the plasma fibrinogen levels and platelet counts on admission. And comparative analysis of the distribution ratio of oriental medicine pattern identification was done between the groups. The mean value of the plasma fibrinogen levels of whole population was 449.18 mg/dL, and it was higher than normal range. The mean value of the platelet counts of whole population was 244.29 /mL, and it was lower but in normal range. Oriental medicine pattern identifications were not characteristic between groups divided according to the serum levels of fibrinogen and platelet counts. In this study, there was not significant correlation between Oriental medicine pattern identifications and the thrombotic factor like plasma fibrinogen levels and platelet counts. This study could be the steppingstone for the next study to develope the objective indicator for the Oriental medicine pattern identifications.

• BMB Reports
• /
• v.29 no.6
• /
• pp.549-554
• /
• 1996

Phosphoinositide turnover in response to platelet-derived growth factor, epidermal growth factor, and bradykinin was evaluated in NIH 3T3 cells. Platelet-derived growth factor and bradykinin induced a significant increase in incorporation of $^{32}P$ into phosphatidylinositol (PI), phosphatidylinositol 4-monophosphate (PIP), and phosphatidylinositol 4.5-bisphosphate ($PIP_2$) in serum-starved NIH 3T3 cells. However, epidermal growth factor increased incorporation of $^{32}P$ into these phosphoinositides by only a small amount. Stimulation with platelet-derived growth factor, not bradykinin, caused a rapid elevation of PI and PIP kinase activities that were maximally activated within 10 min. The maximal levels of their elevation in cells with plateletderived growth factor stimulation were 3.2-fold for PI kinase, and 2.1-fold for PIP kinase. Short term pretreatment of NIH 3T3 cells with phorbol 12-myristate 13-acetate, activator of protein kinase C. caused an approximately 60% decrease in platelet-derived growth factor-induced PI kinase activities, indicating the feedback regulation of phosphoinositide turnover by protein kinase C. These results suggest that although the enhancement of phosphoinositide turnover is a rapidly occurring response in platelet-derived growth factor- or bradykinin-stimulated NIH 3T3 cells, phosphoinositide kinases may be associated with initial signal transduction pathway relevant to platelet-derived growth factor but not to bradykinin.

• Journal of Life Science
• /
• v.24 no.9
• /
• pp.1030-1038
• /
• 2014

Platelet products are used to treat hemorrhagic or platelet dysfunction diseases. Plateletpheresis involves collecting the platelet components of blood using an apheresis blood-collection system. Various indicators are available for evaluating the qualities of the apheresis platelets. The productivity of platelet collection is evaluated through both the collection efficiency and collection rates. Platelet storage quality can be evaluated in vitro using several indicators, including visual appearance, metabolic activities, volume, platelet count, white blood cell count, microparticles, and various platelet activation markers. Platelet activation markers have been used as indicators of storage quality in various studies. Post-transfusion platelet quality can be evaluated based on the corrected count increment and the percentage of platelet recovery. Although various studies have investigated the aspects of plateletpheresis, no article has systemically presented assessments of the platelet products obtained from different plateletpheresis devices. The present study provides a review of plateletpheresis, including the specifics of the process, the types of devices employed, the platelet quality, the overall efficacy, and the evaluation indicator qualities. Furthermore, the differences in functionality among the different apheresis devices are discussed. Although adverse reactions to the citrate anti-coagulant have been reported, apheresis processing may provide a safer option for donors who are at a high risk for presyncopal or syncopal reactions related to whole blood collection.

• Proceedings of the KOSOMBE Conference
• /
• v.1997 no.05
• /
• pp.16-18
• /
• 1997

The adhesion of stimulated and unstimulated platelet to fibrinogen requires the receptor binding site of GPIIb/IIIa. These recognition sites are existed in the Au chain(RGDS at positions 572-575 and RGDF at 95-98) and the carboxyterminal $\gamma$ chain (HHLGGAKQAGDV at 400-411) of fibrinogen. The unstimulated platelet does not adhered on the fragment E-coated surface containing RGDF sequence. In this study, we developed RGDF-immobilized surface to detect the functional state of platelet. RGDF-immobilized surface was prepared on the glass using photolithographic technology. Platelet adhesion to petide(RGDF)-immobilized surface was observed by the fluorescence microscope using mepacrine.

• Polymer(Korea)
• /
• v.25 no.3
• /
• pp.343-348
• /
• 2001

The mechanical and the platelet adhesion properties of the fluorinated polyurethane elastomers synthesized with a perfluorinated polyether diol (Fomblin ZDOL$ZDOL^{(R)}$) and 4,4'-diphenyl methane diisocyanate (MDI) were investigated. The change of mechanical properties with the Fomblin content and the type of the polyether diol was investigated by applying a designed technique using in vitro platelet adhesion test. As a result, the tensile properties were affected by the content and the type of nixed polyether diols. Also the platelet adhesion of polyurethane elastomers decreased with increasing the extent of fluorination in the polymer.

• Korean Journal of Medicinal Crop Science
• /
• v.13 no.4
• /
• pp.178-181
• /
• 2005

Methanolic extracts of fifteen Chinese medicinal plants were screened for platelet-activating factor (PAF) receptor binding inhibitory activity using rabbit platelet. Campsis grandiflora, Dalbergia odorifera, Vaccaria segetalis and Zanthoxylum nitidum showed significant inhibitory effects on the platelet-activating factor (PAF) receptor binding. Campsis grandiflora, Dalbergia odorifera, Vaccaria segetalis and Zanthoxylum nitidum inhibited 52%, 56%, 70%, and 66% respectively at the concentration of 0.2 mg/ml.

• Journal of the Korean Ceramic Society
• /
• v.32 no.12
• /
• pp.1417-1423
• /
• 1995

α/β sialon based composites containing silicon nitride whisker and silicon carbide platelet were fabricated by hot pressing. Effect of the reinforcing agents on the α to β phase transformation of the sialon as well as on the mechanical properties was investigated. Silicon nitride whisker and silicon carbide platelet promoted the phse transformation. TEM/EDS analysis revealed that the grain containing the whisker had 'core-rim' structure; core being high purity Si3N4 whisker and rim being β-sialon. Flexural strength of the composite decreased with the reinforcement addition which, on the other hand, improved fracture toughness of it. High temperature strength was measured at 1300℃ to be about 130 MPa lower than that measured at RT for the whisker reinforced composites.