Effect of a diet rich in potato peel on platelet aggregation / Efecto de una dieta rica en cáscara de papa sobre la agregación plaquetaria

Background: Potato peel extract has demonstrated the ability to reduce platelet aggregation in vitro, suggesting its potential as a dietary intervention for preventing atherothrombotic disorders. Objective: This study aims to evaluate the impact of a potato peel-rich diet on platelet aggregation. Methods: A randomized, crossover-controlled, open two-period study was carried out with the participation of 12 healthy volunteers. Platelet aggregation was assessed before and after a seven-day dietary intervention. Participants consumed either a diet rich in potato peel (2 g/kg/d) or acetylsalicylic acid (ASA) as a reference (100 mg/d). Platelet aggregation percentages were measured following stimulation with arachidonic acid (AA, 150 µg/mL), adenosine diphosphate (ADP, 10 µM), and collagen (COL, 10 µg/mL). Results: The potato peel-rich diet resulted in a slight but significant reduction in platelet aggregation when stimulated with arachidonic acid compared to baseline values (85.0±2.0% vs. 91.3±1.7%, p<0.05). This effect was less pronounced than the reduction achieved with ASA (16±1.9%, p<0.001). Conclusion: The administration of a diet rich in potato peel reduces platelet aggregation induced by arachidonic acid, suggesting its potential role in the prevention of atherothrombotic disorders.

Introducción: El extracto de cáscara de patata ha demostrado su capacidad para reducir la agregación plaquetaria in vitro, lo que sugiere su potencial como intervención dietética para prevenir trastornos aterotrombóticos. Objetivo: Evaluar el impacto de una dieta rica en cáscara de patata en la agregación plaquetaria. Materiales y métodos: Se llevó a cabo un estudio aleatorizado, controlado, cruzado y abierto con la participación de 12 voluntarios sanos. Se evaluó la agregación plaquetaria antes y después de una intervención dietética de siete días. Los participantes consumieron una dieta rica en cáscara de patata (2 g/kg/d) o ácido acetilsalicílico (ASA) como referente (100 mg/d). Se midieron los porcentajes de agregación plaquetaria después de la estimulación con ácido araquidónico (AA, 150 µg/mL), difosfato de adenosina (ADP, 10 µM) y colágeno (COL, 10 µg/mL). Resultados: La dieta rica en cáscara de patata resultó en una ligera pero significativa reducción en la agregación plaquetaria cuando se estimuló con ácido araquidónico en comparación con los valores iniciales (85,0 ± 2,0% vs. 91,3 ± 1,7%, p <0,05). Este efecto fue menos pronunciado que la reducción lograda con ASA (16 ± 1,9%, p <0,001). Conclusión: La administración de una dieta rica en cáscara de patata reduce la agregación plaquetaria inducida por ácido araquidónico, lo que sugiere su papel potencial en la prevención de trastornos aterotrombóticos.

Microfluidic Chip and Flow Cytometry for Examination of the Antiplatelet Effect of Ticagrelor / 中国医学科学院学报

Objective To examine the antiplatelet effect of ticagrelor by microfluidic chip and flow cytometry under shear stress in vitro. Methods Microfluidic chip was used to examine the effect of ticagrelor on platelet aggregation at the shear rates of 300/s and 1500/s.We adopted the surface coverage of platelet aggregation to calculate the half inhibition rate of ticagrelor.The inhibitory effect of ticagrelor on ADP-induced platelet aggregation was verified by optical turbidimetry.Microfluidic chip was used to construct an in vitro vascular stenosis model,with which the platelet reactivity under high shear rate was determined.Furthermore,the effect of ticagrelor on the expression of fibrinogen receptor (PAC-1) and P-selectin (CD62P) on platelet membrane activated by high shear rate was analyzed by flow cytometry. Results At the shear rates of 300/s and 1500/s,ticagrelor inhibited platelet aggregation in a concentration-dependent manner,and the inhibition at 300/s was stronger than that at 1500/s (both P<0.001).Ticagrelor at a concentration ≥4 μmol/L almost completely inhibited platelet aggregation.The inhibition of ADP-induced platelet aggregation by ticagrelor was similar to the results under flow conditions and also in a concentration-dependent manner.Ticagrelor inhibited the expression of PAC-1 and CD62P. Conclusion We employed microfluidic chip to analyze platelet aggregation and flow cytometry to detect platelet activation,which can reveal the responses of different patients to ticagrelor.

Study on Platelet Adhesion and Aggregation Induced by Gradient Shear Stress Using Microfluidic Chip Technology / 中国实验血液学杂志

OBJECTIVE@#To study the effect of gradient shear stress on platelet aggregation by microfluidic chip Technology.@*METHODS@#Microfluidic chip was used to simulate 80% fixed stenotic microchannel, and the hydrodynamic behavior of the stenotic microchannel model was analyzed by the finite element analysis module of sollidwork software. Microfluidic chip was used to analyze the adhesion and aggregation behavior of platelets in patients with different diseases, and flow cytometry was used to detect expression of the platelet activation marker CD62p. Aspirin, Tirofiban and protocatechuic acid were used to treat the blood, and the adhesion and aggregation of platelets were observed by fluorescence microscope.@*RESULTS@#The gradient fluid shear rate produced by the stenosis model of microfluidic chip could induce platelet aggregation, and the degree of platelet adhesion and aggregation increased with the increase of shear rate within a certain range of shear rate. The effect of platelet aggregation in patients with arterial thrombotic diseases were significantly higher than normal group (P<0.05), and the effect of platelet aggregation in patients with myelodysplastic disease was lower than normal group (P<0.05).@*CONCLUSION@#The microfluidic chip analysis technology can accurately analyze and evaluate the platelet adhesion and aggregation effects of various thrombotic diseases unde the environment of the shear rate, and is helpful for auxiliary diagnosis of clinical thrombotic diseases.

Diagnóstico de la enfermedad de von Willebrand / Diagnosis of von Willebrand disease

La enfermedad de von Willebrand (EVW) es el trastorno hemorrágico hereditario más común, y se caracteriza por presentar disminución de la capacidad del factor von Willebrand (FVW) de unirse a las plaquetas y al colágeno de la matriz extracelular durante la hemostasia primaria, debido a defectos cuantitativos o cualitativos. La EVW se clasifica en tres fenotipos principales: el 1 y el 3 que son trastornos cuantitativos, y el 2 que se subclasifica en 2A, 2B, 2M y 2N, y refleja los trastornos cualitativos. Para su diagnóstico son necesarios varios pasos: 1) la evaluación del historial de sangrado personal y familiar del paciente, 2) detección inicial de trastornos hemorrágicos, 3) pruebas para la detección de la EVW, 4) pruebas para la tipificación de la EVW, y 5) el análisis molecular. Tanto la subclasificación de la EVW como su diagnóstico continúan planteando desafíos importantes, motivo por el cual se realiza esta revisión, de manera que los profesionales de la salud tengan una guía que los oriente al momento de tener pacientes con algún trastorno hemorrágico que amerite descartar una EVW e implementar un tratamiento adecuado

von Willebrand disease (VWD) is the most common hereditary bleeding disorder, and is characterized by a decreased ability of the von Willebrand factor (VWF) to bind to platelets and extracellular matrix collagen during primary hemostasis, due to quantitative or qualitative defects. VWD is classified into three main phenotypes: 1 and 3, which are quantitative disorders, and 2 (2A, 2B, 2M and 2N) that reflects qualitative disorders. Several steps are necessary for its diagnosis: 1) evaluation of the patient's personal and family bleeding history, 2) initial screening tests for bleeding disorders, 3) tests for the detection of VWD, 4) tests for the classification of VWD, and 5) molecular analysis. Both the subclassification of VWD and its diagnosis continue to represent important challenges, which we aimed to describe in this review, so that health professionals have a guide to assist them when they have patients with a bleeding disorder that requires exclusion of VWD, and implementation of an appropriate treatment.

Predictors of Hospitalization in Vitamin K Antagonist Users Presenting with Bleeding at the Emergency Department

Abstract Background Vitamin K antagonists (VKA) are indicated for the prevention of thromboembolic events and reduction of mortality in patients with atrial fibrillation and patients with valvular prostheses. However, their use is associated with bleeding complications and hospitalizations. Predictors of hospital admission for bleeding in these patients are poorly known. Objectives To define the predictors for hospitalization of VKA users who seek emergency care due to bleeding. Methods Single-center, cross-sectional study, with retrospective analysis of electronic medical records from 03/01/2012 to 02/27/2017. Clinical and laboratory variables were compared between patients who were hospitalized and those who were not. A logistic regression model as used, in which the variables were included using the Backward stepwise method, with a p value of 0.05 as the input criterion, a removal value of 0.20 and a confidence interval of 95%. The p-value was considered statistically significant when <0.05. Results A total of 510 patients with bleeding were included, of whom 158 were hospitalized. Predictors of hospitalization were: INR at supratherapeutic levels (OR 3.45; P <0.01; 95% CI 1.58 - 7.51), gastrointestinal bleeding (OR 2.36; P <0.01; CI 95% 1.24 - 4.50), drop in hemoglobin (OR 6.93; P <0.01; 95% CI 3.67 - 13.07), heart failure (OR 1.96; P 0.01; 95% CI 1.16 - 3.30) and need for blood transfusion (OR 8.03; P <0.01; 95% CI 2.98 - 21.64). Conclusion Drop in hemoglobin, heart failure, INR at supratherapeutic levels, gastrointestinal bleeding and need for blood transfusion were associated with hospitalization. Identification of these factors in the initial evaluation would help to define which patients will demand more intensive care.

Efficacy-related substances of blood-activating and stasis-resolving medicinals derived from Curcuma plants: a review / 中国中药杂志

Derived from Curcuma plants, Curcumae Longae Rhizoma, Curcumae Rhizoma, Wenyujin Rhizoma Concisum, and Curcumae Radix are common blood-activating and stasis-resolving medicinals in clinical practice, which are mainly used to treat amenorrhea, dysmenorrhea, chest impediment and heart pain, and rheumatic arthralgia caused by blood stasis block. According to modern research, the typical components in medicinals derived from Curcuma plants, like curcumin, demethoxycurcumin, bisdemethoxycurcumin, curdione, germacrone, curcumol, and β-elemene, have the activities of hemorheology improvement, anti-platelet aggregation, anti-thrombosis, anti-inflammation, anti-tumor, and anti-fibrosis, thereby activating blood and resolving stasis. However, due to the difference in origin, medicinal part, processing, and other aspects, the efficacy and clinical application are different. The efficacy-related substances behind the difference have not yet been systematically studied. Thus, focusing on the efficacy-related substances, this study reviewed the background, efficacy and clinical application, efficacy-related substances, and "prediction-identification-verification" research method of blood-activating and stasis-resolving medicinals derived from Curcuma plants, which is expected to lay a theoretical basis for the future research on the "similarities and differences" of such medicinals based on integrated evidence chain and to guide the scientific and rational application of them in clinical practice.

Ligustrazine suppresses platelet aggregation through inhibiting the activities of calcium sensors

Abstract Ligustrazine is widely used for the treatment of cardiovascular diseases in traditional Chinese medication. It has been reported that Ligustrazine decreases the concentration of intracellular calcium ions (Ca2+); however, the underlying mechanism remains unknown. In the present study, the effect of Ligustrazine on adenosine diphosphate (ADP)-induced platelet aggregation was evaluated using a turbidimetric approach. The changes in concentration of intracellular Ca2+ stimulated by ADP was measured using fluo-4, a fluorescent Ca2+ indicator dye. The mRNA expression of stromal interaction molecule l (STIM1) and Orai1, calcium sensor, was determined using real-time PCR. In addition, the protein expression of STIM1, Orai1, and serum/glucocorticoid-regulated protein kinase 1 (SGK1) was determined using Western blot analysis. The data demonstrated that Ligustrazine significantly suppressed platelet aggregation in a dose-dependent manner and reduced the concentration of intracellular Ca2+ triggered by ADP. Our data showed that Ligustrazine treatment inhibited the expression of STIM1 and Orai1 induced by ADP at both mRNA and protein levels, and suppressed the protein expression of SGK1. Taken together, our data indicated that Ligustrazine suppressed platelet aggregation by partly inhibiting the activities of calcium sensors, thereby suggesting that Ligustrazine may be a promising candidate for the treatment of platelet aggregation.

Leaf extract of Coffea arabica L. reduces lipid peroxidation and has anti-platelet effect in a rat dyslipidemia model

Abstract This study aimed to evaluate the antioxidant potential of the Coffea arabica Lineu (L.) leaf extract and its effects on platelet aggregation of dyslipidemic rats. The extract was obtained by the percolation of C. arabica L. leaves in hydroethanolic solution 70% (v/v). The mass spectrometry FIA-ESI-MS² suggested the presence of chlorogenic acid, rutin acid, and quinic acid. The DPPH• radicals scavenging capacity was demonstrated (IC50 = 0.06 mg/mL). The extract was administered to rats by gavage (300 mg/kg/day) for 56 days. Dyslipidemia was induced by administering Triton WR-1339 (300 mg/kg body weight) on the 54th day. On day 56, blood was collected by puncturing the abdominal aorta artery and the aortic artery was removed. Lipid profile, markers of renal and hepatic injury, lipid peroxidation, and platelet aggregation tests were carried out. The ingestion of extract reduced the lipid peroxidation (aorta and plasma) and platelet aggregation in dyslipidemic rats. The extract did not affect markers of renal and hepatic function as analyzed in this study, suggesting neither impaired liver nor kidney function in these animals. Therefore, our results demonstrate that the extract of leaves of C. arabica L. show antioxidant potential in vitro and in vivo as well as anti-platelet aggregation in dyslipidemic animals

Trastornos plaquetarios hereditarios poco frecuentes: patología molecular y aspectos diagnósticos / Infrequent hereditary platelets disorders: molecular pathology and diagnostic aspects

Introducción: Las plaquetas tienen una función clave en la hemostasia primaria a través de cuatro mecanismos fundamentales: adhesión, agregación, secreción y actividad procoagulante, todos controlados genéticamente por más de 50 genes asociados que han sido identificados. Las manifestaciones clínicas en las alteraciones hereditarias de las plaquetas suelen ser variables; aunque estas alteraciones de la coagulación suelen presentarse con una trombocitopenia notoria, también pueden exhibir trombocitopatías, en las cuales la capacidad hemostática de las plaquetas resulta afectada sin variar su número. Por tanto, existen gran variedad de manifestaciones fenotípicas y mutaciones en relación con la función plaquetaria, algunas de las cuales se explicarán más adelante. Objetivo: Realizar revisión práctica sobre mutaciones plaquetarias hereditarias de baja incidencia y destacar la importancia de su conocimiento, correcto diagnóstico, y tratamiento precoz. Métodos: Se realizó revisión literaria en inglés y españolen MEDLINE, EMBASE, Lilacs y ScienceDirect desde mayo 2019 hasta abril 2020, con el uso de combinación de palabras clave y términos MeSH relacionados con trombastenia, genética médica, hemostasis, agregación plaquetaria, trombopoyesis. Se efectuó análisis y resumen de la bibliografía revisada. Conclusión: Entre las alteraciones hereditarias de las plaquetas se pueden encontrar defectos en todos los mecanismos en que participan; sin embargo, la confirmación diagnóstica sigue siendo complicada por el tiempo y el costo que representa lo que ocasiona diagnósticos inadecuados que impactan en el manejo clínico y la evolución(AU)

Introduction: Platelets have a key role in primary hemostasis through four main mechanisms: adhesion, aggregation, secretion and procoagulant activity, all of these controlled by over 50 associated genes that have been identified. Clinical signs of hereditary platelets alterations are usually variable; even though these disorders of hemostasis generally course with a notorious thrombocytopenia, they also might have thrombocytopathies, in which the hemostatic capacity of platelets is affected without altering its number. According to this, there's a great variety of phenotypic manifestations and mutations that affect platelet function, some of these will be explained later on. Objective: To make a practical review of hereditary platelets mutations that have low incidence in population and to highlight the importance of knowing about them, how to diagnose them and early treatment. Methods: A review of literature in both Spanish and English, was done based on MEDLINE, EMBASE, Lilacs and ScienceDirect, during May 2019 and April 2020 using key words and MeSH terms such as thrombasthenia, medical genetics, hemostasis, platelets aggregation, thromopoiesis. Then, an analysis and summary of the reviewed bibliography was carried out. Conclusion: Among the hereditary alterations of platelets, many defects can be found in every mechanism involved; however, diagnostic confirmation is still complicated due to time and cost, causing inaccurate diagnoses that impact on clinic management and evolution(AU)

Study on the intervention of platelet biological activity by ultrasound / 生物医学工程学杂志

Platelets are non-nucleated blood effector cells, which plays an important role in coagulation, hemostasis, and thrombosis. However, platelets are extremely susceptible to activation by external stimuli, which in turn damages the platelet's natural biological activity and affects its biological function. Platelet biological activity has become a hotspot in the field of vascular diseases. In this study, ultrasound parameters (ultrasound intensity and duration time) were used to intervene in the biological activity of platelets. The response of platelets to ultrasound energy was explored from the aspects of platelet morphology, aggregation ability and particle release (the expression of P-selectin and the number of particles). The results showed that the ultrasound intensity of 0.25 W/cm

Correlation of Platelet and Coagulation Function with Blood Stasis Syndrome in Coronary Heart Disease: A Systematic Review and Meta-Analysis / 中国结合医学杂志

OBJECTIVE@#To investigate the correlation of platelet and coagulation function with blood stasis syndrome (BSS) in coronary heart disease (CHD).@*METHODS@#The protocol for this meta-analysis was registered on PROSPERO (CRD42019129452). PubMed, Excerpta Medica Database (Embase), the Cochrane Library, and China National Knowledge Infrastructure (CNKI) were searched from inception to 1st June, 2020. Trials were considered eligible if they enrolled BSS and non-BSS (NBSS) patients with CHD and provided information on platelet and coagulation function. The platelet function, coagulation function, and fibrinolytic activity were compared between the BSS and NBSS groups. Forest plots were generated to show the SMDs or ESs with corresponding 95% CIs for each study. Subgroup analysis and sensitivity analysis were performed to explore potential sources of heterogeneity.@*RESULTS@#The systematic search identified 1,583 articles. Thirty trials involving 10,323 patients were included in the meta-analysis. The results showed that mean platelet volume, platelet distribution width, platelet aggregation rate, platelet P selectin, fibrinogen, plasminogen activator inhibitor-1 (PAI-1), thromboxane B2 (TXB2), 6-keto-prostaglandin F1alpha (6-keto-PGF1 α), and TXB2/6-keto-PGF1 α were higher in the BSS group than in the NBSS group (P<0.05 or P<0.01). Activated partial thromboplastin time was lower in the BSS group than in the NBSS group in the acute phase of CHD (P<0.01). The R and K values in thromboelastography and tissue plasminogen activator (t-PA) and t-PA/PAI-1 were lower in the BSS group than in the NBSS group (all P<0.01). No difference was found in the results of platelet count, plateletcrit, maximum amplitude, von Willebrand factor, prothrombin time, thrombin time, international normalized ratio, etc. between groups.@*CONCLUSIONS@#Increased platelet function, hypercoagulability, and decreased fibrinolytic activity were found among CHD patients with BSS.

Estudios de agregación plaquetaria como endofenotipo de las alteraciones hereditarias de la fibra colágena / Platelet aggregation studies as an endophenotype of hereditary disorders of collagen fiber

Introducción: Las plaquetas contribuyen a la hemostasia y la interrupción heredada o adquirida; en sus procesos bioquímicos pueden alterar la función plaquetaria. Estos trastornos de agregación se han asociado a enfermedades genéticas con afectación del tejido conectivo como el síndrome Ehlers-Danlos, cuyo diagnóstico diferencial con el espectro de hipermovilidad articular resulta difícil clínica y molecularmente. Estas entidades con afectación en las fibras colágenas y diferente repercusión clínica precisan diferenciales en su diagnóstico clínico. Métodos: Se revisaron 353 historias clínicas de pacientes atendidos en el Servicio de Genética del Hospital Pediátrico William Soler desde septiembre del 2009 al 2012, con diagnóstico de hipermovilidad articular por criterios de Beighton y de Ehlers-Danlos según Villefranche (1997). Se incluyó a los pacientes de 5-18 años con resultados documentados del estudio de agregación plaquetaria, valorados por especialistas en hematología. Resultados: Se encontraron trastornos de agregación plaquetaria en 79 de 86 pacientes (92 por ciento). En 7 casos con hipermovilidad de 65 con este diagnóstico (10 por ciento), los resultados fueron negativos. Los 21 con síndrome Ehlers-Danlos tuvieron afectaciones con los fosfolípidos plaquetarios. La hipermovilidad articular estuvo asociada a la combinación difosfato de adenosina (ADP)-epinefrina y el Ehlers-Danlos a la combinación ADP-epinefrina-colágeno-fosfolípidos. Conclusiones: Los pacientes con hipermovilidad articular mostraron asociación a defectos de liberación de gránulos con agonistas como el ADP-epinefrina y los Ehlers-Danlos con la disponibilidad de los fosfolípidos, relacionados con el cambio de forma plaquetaria. Este resultado puede ser una herramienta para conocer el endofenotipo funcional plaquetario como elemento diferencial en los trastornos de la fibra colágena(AU)

Introduction: Platelets contribute to hemostasis and inherited or acquired interruption; in its biochemical processes it can alter platelet function. These aggregation disorders have been associated with genetic diseases with connective tissue involvement such as Ehlers-Danlos syndrome, whose differential diagnosis with the spectrum of joint hypermobility is clinically and molecularly difficult. These entities with involvement of the collagen fibers and different clinical repercussions require differentials in their clinical diagnosis. Methods: 353 medical records of patients attended in the Genetics service of the William Soler Pediatric Hospital from September 2009 to 2012, with a diagnosis of joint hypermobility by Beighton and Ehlers-Danlos criteria according to Villefranche (1997) were reviewed. Patients aged 5-18 years were included with documented results of the platelet aggregation study, assessed by specialists in hematology. Results: Platelet aggregation disorders were found in 79 of 86 patients (92 percent). In 7 cases with hypermobility of 65 with this diagnosis (10 percent), the results were negative. The 21 with Ehlers-Danlos syndrome had affectations with platelet phospholipids. Joint hypermobility was associated with the combination adenosine diphosphate (ADP) -epinephrine and the Ehlers-Danlos with the combination ADP-epinephrine-collagen-phospholipids. Conclusions: Patients with joint hypermobility showed an association to granule release defects with agonists such as ADP-epinephrine and Ehlers-Danlos with the availability of phospholipids, related to platelet shape change. This result can be a tool to know the platelet functional endophenotype as a differential element in collagen fiber disorders(AU)

Respuesta de los sujetos con hipertensión arterial a los fármacos antiagregantes plaquetarios / Response of hypertensive subjects to antiplatelet drugs

Introducción: La terapia con antiagregantes plaquetarios es recomendada como prevención secundaria de eventos cardiovasculares en personas con hipertensión arterial. Sin embargo, en la práctica clínica se encuentran personas que no responden al tratamiento y presentan recurrencia de eventos vasculares. Objetivo: Evaluar la respuesta de los sujetos hipertensos a los fármacos antiagregantes plaquetarios. Material y Métodos: Estudio transversal, observacional descriptivo y comparativo, con 299 sujetos con hipertensión arterial esencial y 96 no hipertensos (como control), que estaban consumiendo antiagregantes plaquetarios. Los sujetos hipertensos fueron agrupados de acuerdo con el consumo de fármacos antihipertensivos. Se les determinó su agregación plaquetaria al colágeno en plasma, rico en plaquetas, según el Método de Born. La respuesta a la terapia antiplaquetaria se clasificó en cuatro categorías (óptima, moderada, pobre y no respuesta) de acuerdo con la agregación plaquetaria. Resultados: Se observó una ligera mejor respuesta a los antiagregantes plaquetarios, aunque no estadísticamente significativa, por parte de los hipertensos sin fármacos antihipertensivos (35,7 por ciento óptima y 42,9 por ciento moderada), en relación con los hipertensos que usaban antihipertensivos (32,7 por ciento óptima y 26,5 por ciento moderada) y los no hipertensos (30,2 por ciento óptima y 30,2 por ciento moderada). Además, se encontró que 17,7 por ciento de los sujetos no hipertensos, 14,3 por ciento de los hipertensos sin fármacos antihipertensivos y 13,2 por ciento de los hipertensos con antihipertensivos no estaban respondiendo a los antiagregantes plaquetarios. Conclusiones: La respuesta a los fármacos antiagregantes plaquetarios de los sujetos hipertensos consuman o no fármacos antihipertensivos es heterogénea y similar a la de los sujetos no hipertensos(AU)

ABSTRACT Introduction: Therapy with antiplatelet drugs is recommended as secondary prevention of cardiovascular events in people with arterial hypertension. However, in the clinical practice, there are people who do not respond to treatment and evidence a recurrence of vascular events. Objective: To evaluate the response of hypertensive patients to antiplatelet drugs. Material and Methods: Cross-sectional, observational, descriptive and comparative study that included 299 subjects with arterial hypertension and 96 non-hypertensive subjects (control group) who were taking antiplatelet drugs. The hypertensive subjects were grouped according to the consumption of antihypertensive drugs. Platelet aggregation collagen in platelet-rich plasma was determined using the turbidimetric Born's method. The response to the antiplatelet therapy was classified in four categories (good, moderate, poor and non-responsiveness) in accordance with the platelet aggregation. Results: There was a slightly better response to antiplatelet drugs, although it was not statistically significant in hypertensive subjects without antihypertensive drugs (35,7 percent good and 42,9 percent moderate) in relation to hypertensive subjects who were taking antihypertensive drugs (32,7 percent good and 26,5 percent moderate) and the non-hypertensive ones (30,2 percent good and 30,2 percent moderate).Besides, it was found that 17,7 percent of non-hypertensive subjects and 14,3 percent of the hypertensive ones without antihypertensive drugs and 13,2 percent of hypertensive subjects with antihypertensive drugs were not responding to the treatment with antiplatelet drugs. Conclusions: The response of hypertensive patients to antiplatelet drugs, either taking antihypertensive drugs or not, is heterogeneous and similar to the response of the non-hypertensive subjects(AU)

Resveratrol inhibits Ca

BACKGROUND@#Resveratrol has been shown to inhibit platelet aggregation. However, the mechanism for this action of resveratrol remains to be clarified. The purpose of this study was to elucidate the Ca@*METHODS@#Ca@*RESULTS@#Thapsigargin-induced Ca@*CONCLUSIONS@#The results suggest that resveratrol inhibits thrombin-induced platelet aggregation through decreasing Ca

Advances in studies on steroidal alkaloids and their pharmacological activities in genus Veratrum / 中国中药杂志

Genus Veratrum plants contain a diversity of steroidal alkaloids, so far at least 184 steroidal alkaloids attributed to cevanine type(A-1～A-69), veratramine type(B-1～B-21), jervanine type(C-1～C-31), solanidine type(D-1～D-10) and verazine type(E-1～E-53), respectively, have been isolated and identified in the genus Veratrum. Their pharmacological activities mainly focused on decreasing blood pressure, anti-platelet aggregation and anti-thrombosis, anti-inflammatory and analgesic, and antitumor effect. This paper classified and summarized the 184 kind of steroidal alkaloids from the Veratrum plants and their major pharmalogical activities in order to provide the scientific basis for the further development and utilization of active alkaloids.

Effect of Protein Kinase A Activation on Aggregation Function of Platelets / 中国实验血液学杂志

OBJECTIVE@#To investigate the effect of protein kinase A (PKA) activation on aggregation funetion of platelets in vitro.@*METHODS@#The peripheral blood of healthy adults were collected, and the washed platelets were gained from collected peripheral blood. The washed platelets were treated with PKA activator Forskolin, then the platelet aggregation was induced by using Ristocetin, Thrombin, Collagen and ADP respectively, the platelet aggregation level was detected by the platelet aggregator.@*RESULTS@#Compared with the controls, 5 μmol/L forskolin significantly inhibited ADP and collagen-induced platelet aggregation (P＜0.001), and showed mild inhibiting effect on Thrombin-induced platelet aggregation (P＜0.05). 2.5-10 μmol/L forskolin significantly inhibited ADP and Collagen -induced platelet aggregation (P＜0.001); but not showed significantly inhibitory effects on Ristocetin-induced platelet aggregation (P＞0.05).@*CONCLUSION@#PKA activation inhibits agonists-induced platelet aggregation.

Trombocitopenia por agregados plaquetarios / Thrombocytopenia by aggregated platelet: case report

Introducción: la pseudotrombocitopenia inducida por EDTA (ácido etilendiamino tetraacético) es un fenómeno de aglutinación de plaquetas que se presenta in vitro, mediado por anticuerpos anti-plaquetarios de tipo IgG, IgA o IgM dirigidos contra el complejo glucoproteínico IIb/IIIa de la membrana plaquetaria. Caso clínico: presentamos un caso clínico de una paciente de 59 años de edad sometida a recambio valvular aórtico; clínicamente con evolución favorable durante el periodo posquirúrgico, sin embargo, en estudios de control se registra trombocitopenia severa, lo que llevo a cuestionar el uso de anticoagulantes y la necesidad de transfusión de plaquetas. Al realizar estudios complementarios se encontró agregados plaquetarios en el frotis de sangre periférica, posteriormente se realizó recuento seriado de plaquetas y comparación del histograma plaquetario, catalogando el caso como pseudotrombocitopenia. Conclusión: La trombocitopenia por agregados plaquetarios es una condición de baja incidencia (0.07% a 0.1%). Se debe a la agregación de plaquetas in vitro asociada al uso de anticoagulantes, frecuentemente etilendiaminotetraacético (EDTA), en el presente caso también se asoció al uso de citrato de sodio. Este problema no se asocia a sangrado, sin embargo su desconocimiento pudo haber llevado a realizar procedimientos diagnósticos y terapéuticos innecesarios

Introduction: EDTA (ethylenediamine tetraacetic acid) ­induced by pseudothrombocytopenia is a platelet agglutination phenomenon that occurs in vitro, which are mediated by anti-platelet antibodies of the IgG, IgA or IgM type directed against the glycoprotein complex IIb / IIIa of the platelet membrane . Clinical case: This is a clinical case of a 59-yearsold patient undergoing aortic valve replacement, clinically with a favorable evolution during the postoperative period, however, in control studies, severe thrombocytopenia was recorded, which led to questioning the use of anticoagulants and the need for platelet transfusion. When carrying out complementary studies, aggregated platelet were found in the peripheral blood smear, later, a serial platelet count and comparison of the platelet histogram were performed, classifying the case as pseudotrombocytopenia. Conclusion: Thrombocytopenia due to aggregated platelet is a low incidence condition (0.07% to 0.1%). It is due to the aggregation of platelets in vitro associated with the use of anticoagulants [frequently ethylenediamine tetra acetic (EDTA)]; in the present case it was also associated with the use of sodium citrate. This problem is not associated with bleeding; however its lack of knowledge leads to unnecessary diagnostic and therapeutic procedures.

Low triiodothyronine syndrome is associated with platelet function in patients with nephrotic syndrome

SUMMARY OBJECTIVE The objective of this study was to investigate the effects of low triiodothyronine syndrome (LT3S) on platelet function and clotting factors in patients with nephrotic syndrome(NS). METHODS Patients with primary nephrotic syndrome were divided into two groups, normal thyroid function (group A) and LT3S (group B), based on whether they had LT3S or not. Healthy subjects were selected as the control group (group C). Blood coagulation function was detected in each group. The platelet activation function (CD62P, CD63) was determined by flow cytometry. The platelet aggregation rate was detected by an optical method using adenosine diphosphate and arachidonic acid as inducers. RESULTS The proportion of primary nephrotic syndrome with LT3S was 23.2% (69/298). Compared with group C, group A had higher CD62P and PAgTADP, and group B had higher CD62P, CD63, PAgTAA, and PAgTADP; the difference was statistically significant (all P < 0.05). There was no significant difference in renal pathology between group A and group B (X2 = 4.957, P = 0.421). Compared with group A, the 24-hour urine protein, CD63, PAgTAA, and PAgTADP were higher in group B, and APTT and Alb were lower. The difference was statistically significant (P < 0.05). Logistic regression analysis showed that LT3S was associated with CD36 (OR: 3.516; 95% CI: 1.742~8.186; P = 0.004) and PAgTAA (OR: 0.442; 95% CI: 1.001~1.251; P = 0.037). CONCLUSION NS patients are prone to LT3S. Patients with LT3S may have abnormal platelet activation and increase of platelet aggregation.

RESUMO OBJETIVO O objetivo deste estudo foi investigar os efeitos da síndrome do baixo triiodotironina (LT3S) na função plaquetária e nos fatores de coagulação em pacientes com síndrome nefrótica (SN). MÉTODOS Pacientes com síndrome nefrótica primária foram divididos em dois grupos, função tireoidiana normal (grupo A) e LT3S (grupo B), com base na presença ou não de LT3S. Indivíduos saudáveis foram selecionados como grupo de controle (grupo C). A função de coagulação do sangue foi analisada em cada grupo. A função de ativação plaquetária (CD62P, CD63) foi determinada por citometria de fluxo. A taxa de agregação plaquetária foi detectada por um método óptico usando adenosina difosfato e ácido araquidônico como indutores. RESULTADOS A proporção de síndrome nefrótica primária com LT3S foi de 23,2% (69/298). Em comparação com o grupo C, o grupo A apresentou níveis mais altos de CD62P e PAgTADP, e o grupo B apresentou maiores CD62P, CD63, PAgTAA e PAgTADP; a diferença teve significância estatística (P < 0,05). Não houve diferença significativa na patologia renal entre o grupo A e o grupo B (X2 = 4,957, P = 0,421). Em comparação com o grupo A, a proteína em urina de 24 horas, CD63, PAgTAA e PAgTADP foram maiores no grupo B, já APTT e Alb foram mais baixos. A diferença apresentou significância estatística (P < 0,05). A análise de regressão logística mostrou uma associação entre LT3S e CD36 (OR: 3,516; 95% IC: 1,742~8,186; P = 0,004) e PAgTAA (OR: 0,442; 95% IC: 1,001~1,251; P = 0,037). CONCLUSÃO Pacientes com síndrome nefrótica estão propensos à síndrome do baixo triiodotironina (LT3S). Pacientes com LT3S podem ter ativação plaquetária anormal e aumento da agregação plaquetária.

Efecto de la hiperglucemia en el síndrome coronario agudo y sus implicaciones en el tratamiento antiagregante plaquetario / Effect of hyperglycemia on acute coronary syndrome and the implications of antiplatelet therapy

RESUMEN La enfermedad cardiovascular representa, según los datos de la Organización Mundial de la Salud, la principal causa de muerte asociada con factores de riesgo como el tabaquismo, el sedentarismo, la hipertensión, la dislipidemia y la diabetes mellitus. Precisamente, esta última enfermedad es una de las que más se relaciona con la aparición, la progresión y las complicaciones de un evento coronario. La hiperglucemia potencia diferentes vías bioquímicas y celulares como la del sorbitol, el factor nuclear kβ, la formación de productos finales de glicación avanzada, la vía de la proteína cinasa C y el estrés oxidativo, que terminan favoreciendo en el paciente coronario un estado proinflamatorio y procoagulante, que se asocia con un peor pronóstico y agrava la lesión miocárdica; además, inhibe y compite con la acción de los antiagregantes plaquetarios, generando resistencia no solo a estos sino también a la terapia trombolítica. Por lo anterior, se hace necesario generar una actualización del tema, para sensibilizar a la comunidad médica sobre la importancia del control glucémico, sobre todo en pacientes con cardiopatía isquémica, y así mejorar las estrategias de control. Se realizó la búsqueda bibliográfica en PubMed, de una forma estructurada, no sistemática. Se incluyeron artículos publicados en inglés y español, sin restricción por fecha de publicación.

SUMMARY According to data from the World Health Organization, cardiovascular disease is the main cause of death associated with risk factors such as smoking, sedentary lifestyle, hypertension, dyslipidemia and diabetes mellitus. Precisely, this last disease is one of the most related to the appearance, progression, and complications of a coronary event. Hyperglycemia potentiates different biochemical and cellular pathways such as sorbitol, the nuclear factor kβ, the formation of advanced glycation end products, the protein kinase C pathway and oxidative stress, which end up favoring in the coronary patient a proinflammatory state and procoagulant, which is associated with a worse prognosis and aggravates myocardial injury; in addition, it inhibits and competes with the action of platelet antiaggregants, generating resistance not only to these but also to thrombolytic therapy. Therefore, it is necessary to generate an update of the topic, to sensitize the medical community about the importance of glycemic control, especially in patients with ischemic heart disease and thus improve control strategies. The bibliographic search was carried out in PubMed, in a structured, non-systematic way. Articles published in English and Spanish were included, without restriction by publication date.

Platelet function, coagulation and fibrinolysis in patients with previous coronary and cerebrovascular ischemic events

OBJECTIVES: Ischemic stroke (IS) or transient ischemic attack (TIA) history is present in 4-17% of patients with coronary artery disease (CAD). This subgroup of patients is at high risk for both ischemic and bleeding events. The aim of this study was to determine the role of platelet aggregability, coagulation and endogenous fibrinolysis in patients with CAD and previous IS or TIA. METHODS: A prospective case-control study that included 140 stable CAD patients divided into two groups: the CASE group (those with a previous IS/TIA, n=70) and the CONTROL group (those without a previous IS/TIA, n=70). Platelet aggregability (VerifyNow Aspirin® and VerifyNow P2Y12®), coagulation (fibrinogen and thromboelastography by Reorox®) and endogenous fibrinolysis (D dimer and plasminogen activator inhibitor-1) were evaluated. RESULTS: Patients in the CASE group presented significantly higher systolic blood pressure levels (135.84±16.09 vs 123.68±16.11, p<0.01), significantly more previous CABG (25.71% vs 10%, p=0.015) and significantly higher calcium channel blocker usage (42.86% vs 24.29%, p=0.02) than those in the control group. In the adjusted models, low triglyceride values, low hemoglobin values and higher systolic blood pressure were significantly associated with previous IS/TIA (CASE group). Most importantly, platelet aggregability, coagulation and fibrinolysis tests were not independently associated with previous cerebrovascular ischemic events (CASE group). CONCLUSION: Platelet aggregability, coagulation and endogenous fibrinolysis showed similar results among CAD patients with and without previous IS/TIA. Therefore, it remains necessary to identify other targets to explain the higher bleeding risk presented by these patients.