Main Factors Influencing the Platelet Spreading / 中国实验血液学杂志

OBJECTIVE@#To explore the main factors of platelet spreading and provide the foundation for related research.@*METHODS@#Platelets (2×107/ml) were draw from C57BL/6J mouse and kept at 22 ℃ for 1-2 hours. Platelets (2×107/ml) were were allowed to adhere and spread on the fibrinogen-coated slides, after staining F-actin in platelets, the platelets were observed with the confocal microscopy. The effects of different concentrations of fibrinogen (10 μg/ml, 30 μg/ml, 100 μg/ml) and kinds of agonists ［thrombin(0.01,0.05,0.1 U/ml), ADP（5,10,20 μmol/L）, U46619（0.125,0.25,0.5 μmol/L）］ on platelets were analyzed. The platelet spreading was successful if the spreading rate was higher after treated with agonists.@*RESULTS@#Compared to the group which coated with 10 μg/ml and 100 μg/ml fibrinogen, the platelet density is optimal when coated with 30 μg/ml fibrinogen. In addition, under the stimulation of thrombin, ADP and U46619, the spreading rate of platelets showed a certain concentration-dependent increasing.@*CONCLUSION@#The platelet spreading is easily influenced by various factors, the platelet spreading can be induced successfully at 0.1 U/ml thrombin, 20 μmol/L ADP and 0.5 μmol/L U46619 on the slide coated with 30 μg/ml fibrinogen.

Lisado plaquetario autólogo y su efectividad en pacientes con epicondilitis / Autologous platelet lysate and its effectiveness in patients with epicondylitis

Introducción: La epicondilitis constituye uno de los motivos de consulta más frecuentes tanto en la asistencia primaria como especializada y sin duda alguna, es uno de los problemas que tiene mayor repercusión en la persona que la padece. El tratamiento de las epicondilitis constituye un reto para la medicina debido a enormes implicaciones sanitarias, sociolaborales y el dolor e impotencia funcional que provoca. Objetivo: Evaluar la efectividad del lisado plaquetario autólogo como alternativa de tratamiento en pacientes enfermos con epicondilitis. Método: Se realizó un estudio cuasi experimental analítico longitudinal prospectivo en el que se evaluó el uso de lisado plaquetario autólogo como alternativa de tratamiento en pacientes con epicondilitis. El universo estuvo constituido por los pacientes que acudieron a consulta de Ortopedia y traumatología con el diagnóstico de epicondilitis, durante el periodo comprendido entre octubre de 2014 y julio de 2018. La muestra quedo constituida por 80 pacientes que cumplieron con los criterios de inclusión y exclusión. Resultados: El grupo de edad entre 36-56 años y del sexo femenino son los de mayor representación en padecer esta enfermedad. Las infiltraciones de lisado plaquetario autólogo aportan mejores resultados al convencional y se observa la mayor representación de pacientes que tuvieron una remisión total. Las complicaciones fueron mucho más evidentes en el tratamiento convencional. También es relevante el costo-beneficio del tratamiento con lisado plaquetario autólogo. Conclusiones: El tratamiento con lisado plaquetario autólogo puede ser una alternativa para mejorar la calidad de vida de los pacientes con epicondilitis(AU)

Introduction: Epicondylitis is one of the most frequent reasons for attending consultation in both primary and specialized care; while it is undoubtedly one of the problems with the greatest impact on the person who suffers from it. The managment epicondylitis is a challenge for medicine, due to the enormous health-related and social implications, as well as the pain and functional impotence that it causes. Objective: To assess the effectiveness of autologous platelet lysate as a treatment alternative in patients with epicondylitis. Method: A prospective, longitudinal, analytical and quasiexperimental study was carried out, in which the use of autologous platelet lysate as an alternative treatment in patients with epicondylitis was assessed. The universe consisted of patients who attended the orthopedics and traumatology consultation, during the period between October 2014 and July 2018, with a diagnosis of epicondylitis. The sample was made up of eighty patients who met the inclusion criteria; exclusion criteria were also considered. Results: The age group between 36 and 56 years, together with the female sex, are the most represented with respect to suffering from this disease. Infiltrations of autologous platelet lysate provide better outcomes than the conventional one, while greater representation of remitted patients is observed. Complications were much more evident in conventional treatment. The cost-benefit relationship of treatment with autologous platelet lysate is also relevant. Conclusions: Treatment with autologous platelet lysate can be an alternative to improve the quality of life of patients with epicondylitis(AU)

COVID-19 in Pregnancy: Implication on Platelets and Blood Indices / COVID-19 na gravidez: implicações nas plaquetas e índices sanguíneos

Abstract Objective To describe the hematological changes, the platelet indices in particular, in pregnant women with coronavirus disease 2019 (COVID-19) compared to healthy pregnant women. Methods A retrospective case-control study conducted at the Al Yarmouk Teaching Hospital, in Baghdad, Iraq, involving 100 pregnant women, 50 with positive viral DNA for COVID-19 (case group), and 50 with negative results (control group); both groups were subjected to a thorough hematological evaluation. Results Among the main hematological variables analyzed, the platelet indices, namely the mean platelet volume (MPV) and the platelet distribution width (PDW), showed statistically significant differences (MPV: 10.87±66.92 fL for the case group versus 9.84±1.2 fL for the control group; PDW: 14.82±3.18 fL for the case group versus 13.3±2.16 fL for the controls). The criterionvalue of the receiver operating characteristic (ROC) curve forPDWat a cutoffpoint of>11.8 fL showed a weak diagnostic marker, while the MPV at a cutoff value of>10.17 fL showed a good diagnostic marker. Conclusion The MPV and PDW are significantly affected by the this viral infection, even in asymptomatic confirmed cases, and we recommend that both parameters be included in the diagnostic panel of this infection.

Resumo Objetivo Descrever as alterações hematológicas, em particular os índices plaquetários em gestantes com doença coronavírus 2019 (COVID-19) em comparação com gestantes saudáveis. Métodos Estudo caso-controle retrospectivo realizado no Hospital Universitário Al Yarmouk, em Bagdá, Iraque envolvendo 100 gestantes, 50 com DNA viral positivo para COVID-19 (grupo caso) e 50 com resultados negativos (grupo controle); ambos os grupos foram submetidos a uma avaliação hematológica completa. Resultados Entre as principais variáveis hematológicas analisadas, os índices plaquetários, nomeadamente o volume plaquetário médio (VPM) e a largura de distribuição plaquetária (PDW), apresentaram diferenças estatisticamente significativas (VPM: 10,87±66,92 fL para o grupo caso versus 9,84±1.2 fL para o o grupo controle; PDW: 14,82±3,18 fL para o grupo caso versus 13,3±2,16 fL para os controles). O valor de critério da curva de característica de operação do receptor (ROC) para PDW em um ponto de corte de> 11,8 fL mostrou um marcador diagnóstico fraco, enquanto o do VPM emumvalor de corte de> 10,17 fL mostrou um bom marcador de diagnóstico. Conclusão OMPVe PDWsão significativamente afetados por esta infecção viral, mesmo em casos confirmados assintomáticos, e recomendamos que ambos os parâmetros sejam incluídos no painel de diagnóstico desta infecção.

National expert consensus on application of enriched platelet products in wound repair (2020 version) / 中华烧伤杂志

Wound biotherapy, represented by platelet concentrate derivatives, has attracted much attention. However, there are some different viewpoints due to the disunity of quality control of preparation, the ways of use, and so on. The members of the consensus writing group reviewed a large number of literatures, screened out high-quality evidence references, combined with the repeated discussion of experts in the field of wound repair to form a guiding consensus of experts, so as to guide medical personnel using enriched platelet treatment scientifically and standardly in wound repair.

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.

The predictive effects of clinical hematological changes on saphenous graft patency after coronary artery surgery

Abstract Objectives: To investigate the association between clinical hematologic parameters and saphenous vein graft failure after on-pump coronary artery bypass surgery. Methods: A total of 1950 consecutive patients underwent isolated on-pump coronary artery surgery between November 2010 and February 2013. Of these, 284 patients met our inclusion criteria; their preoperative clinical hematological parameters were retrospectively obtained for this cohort study. And of them, 109 patients underwent conventional coronary angiography after graft failure was revealed by coronary computed tomography angiography. The primary endpoint was to catch at least one saphenous vein graft stenosis or occlusion following the coronary angiogram. We then analyzed risk factors for graft failure. In sequential or T grafts, each segment was analyzed as a separate graft. Results: In logistic regression analysis, older age, platelet distribution width, and diabetes mellitus were identified as independent predictors of saphenous vein graft failure (P<0.). In contrast, preserved ejection fraction value favored graft patency (P<0.001). Conclusion: Increased platelet distribution width is easily measurable and can be used as a simple and valuable marker in the prediction of saphenous vein graft failure.

Platelets volume indexes and cardiovascular risk factors

SUMMARY Obesity, diabetes and hypertension are risk factors for cardiovascular diseases (CVD) because they promote a state of hypercoagulability. It is known that platelets play an important role in the development of atherosclerosis. Recent studies have evaluated platelet volume indexes (PVIs) in individuals with risk factors for CVD to better understand the platelet mechanisms involved in their development. The IVPs indirectly estimate platelet function and are easily obtained from automated hematology analyzers, which provide platelet counts, mean platelet volume (MPV), platelet distribution width (PDW) and the platelet-large cell ratio (P-LCR). The present study aims to review literature studies that investigated the association between PVIs and obesity, diabetes, and arterial hypertension, in order to evaluate its use as a potential subclinical marker of CVD. Studies have shown promising results for MPV, an index that allows for early detection of platelet activation and may be useful in identifying patients before the onset of CVD development so that preventive strategies can be implemented. The PDW, although evaluated by a smaller number of studies, also showed promising results. However, there is still a long way to go in order for the MPV and PDW to be used in clinical practice, since there is still a need for more epidemiological evidence, establishing reference values, and standardizing the way results are presented.

RESUMO A obesidade, o diabetes e a hipertensão arterial são fatores de risco para as doenças cardiovasculares (DCV) por promoverem um estado de hipercoagulabilidade. É sabido que as plaquetas desempenham um importante papel no desenvolvimento da aterosclerose. Diante disso, estudos recentes têm avaliado os índices de volumes plaquetários (IVPs) em indivíduos com fatores de risco para DCV, para melhor se entenderem os mecanismos plaquetários envolvidos no seu desenvolvimento. Os IVPs estimam indiretamente a função plaquetária e são facilmente obtidos a partir de analisadores hematológicos automáticos, que fornecem contagens de plaquetas, volume médio de plaquetas (VPM), largura de distribuição de plaquetas (PDW) e a proporção de plaquetas grandes (P-LCR). O presente trabalho tem por objetivo revisar na literatura estudos que investigaram a associação entre os IVPs e obesidade, diabetes e hipertensão arterial, a fim de avaliar o seu uso como potencial marcador subclínico das DCV. Estudos demonstraram resultados promissores quanto ao VPM, um índice que permite uma detecção precoce da ativação de plaquetas e que pode ser útil na identificação de pacientes antes do início do desenvolvimento de DCV, de tal forma que estratégias preventivas possam ser implantadas. O PDW, embora tenha sido avaliado por um número menor de estudos, também demonstrou resultados promissores. Entretanto, ainda existe um longo caminho a se percorrer para que o VPM e o PDW sejam utilizados na prática clínica, pois ainda são necessárias mais evidências epidemiológicas, o estabelecimento de valores de referência e a padronização da forma de expressar os resultados.

Membrana de fibrina versus injerto conectivo como tratamiento de recesión gingival / Fibrin membrane versus connective tissue graft as gingival recession treatment

RESUMEN: Este caso clínico de boca dividida a 6 meses tiene como objetivo comparar los resultados obtenidos con una membrana de fibrina rica en plaquetas y leucocitos (L-PRF) y un injerto de tejido conectivo (ITC) en el tratamiento de recesiones gingivales clase1 de Miller en un paciente con biotipo gingival grueso. El resultado muestra que el uso de una membrana de L-PRF provee un parcial cubrimiento de la recesión y un menor malestar subjetivo del paciente cuando se compara con el ITC. Sin embargo, el ITC proporciona un mayor porcentaje de cubrimiento radicular y un mejor resultado estético que la membrana de L-PRF al cabo de 6 meses.

ABSTRACT: The aim of this split-mouth clinical study, covering a 6 month period, is to compare the results obtained from Leucocyte and Platelet Rich Fibrin Membrane (L-PRF) and Connective Tissue Grafting (CTG) in the treatment of class 1 Miller gingival recessions in a patient with thick gingival biotype. The results show that the use of L-PRF membrane provides partial coverage of the recession, as well as lower subjective patient discomfort when compared with CTG. However, CTG provides a higher percentage of root coverage and better aesthetic results than the L-PRF membrane after a period of 6 months.

Effects of Chronic Exercise on Endothelial Progenitor Cells and Microparticles in Professional Runners / Efeitos de Exercício Crônico Sobre Células Progenitoras Endoteliais e Micropartículas em Corredores Profissionais

Abstract Background: The effects of chronic exposure to exercise training on vascular biomarkers have been poorly explored. Objective: Our study aimed to compare the amounts of endothelial progenitor cells (EPCs), and endothelial (EMP) and platelet (PMP) microparticles between professional runners and healthy controls. Methods: Twenty-five half-marathon runners and 24 age- and gender-matched healthy controls were included in the study. EPCs (CD34+/KDR+, CD133+/KDR+, and CD34+/CD133+), EMP (CD51+) and PMP (CD42+/CD31+) were quantified by flow-cytometry. All blood samples were obtained after 12 h of fasting and the athletes were encouraged to perform their routine exercises on the day before. Results: As compared with controls, the CD34+/KDR+ EPCs (p=0.038) and CD133+/KDR+ EPCs (p=0.018) were increased, whereas CD34+/CD133+ EPCs were not different (p=0.51) in athletes. In addition, there was no difference in MPs levels between the groups. Conclusion: Chronic exposure to exercise in professional runners was associated with higher percentage of EPCs. Taking into account the similar number of MPs in athletes and controls, the study suggests a favorable effect of exercise on these vascular biomarkers.

Resumo Fundamento: Os efeitos da exposição crônica ao exercício sobre biomarcadores vasculares foram pouco estudados. Objetivo: Nosso estudo teve como objetivo comparar as quantidades de células progenitoras endoteliais (CPEs), e de micropartículas endoteliais (MPEs) e plequetárias (MPPs) de corredores profissionais com controles sadios. Métodos: Vinte e cinco corredores de meia maratona e 24 controles pareados quanto à idade e ao sexo foram incluídos no estudo. CPEs (CD34+/KDR+, CD133+/KDR+ e CD34+/CD133+), MPE (CD51+) e MPPs (CD42+/CD31+) foram quantificadas por citometria de fluxo. Todas as amostras de sangue foram obtidas após 12 horas de jejum, e os atletas foram incentivados a realizar seus exercícios de rotina no dia anterior à coleta. Resultados: Em comparação aos controles, CPEs CD34+/KDR+ (p=0,038) e CD133+/KDR+ (p=0,018) estavam aumentados, e CPEs CD34+/CD133+ não foram diferentes (p=0,51) nos atletas. As concentrações de MP não diferiram entre os grupos. Conclusão: A exposição crônica ao exercício em corredores profissionais associou-se a uma maior porcentagem de CPEs. Considerando o número similar de MPs entre atletas e controles, o estudo sugere um efeito favorável do exercício sobre esses biomarcadores vasculares.

Three-dimensional structure and cytokine distribution of platelet-rich fibrin

OBJECTIVES: Previous reports have revealed that several cytokines (including platelet-derived growth factor-BB, transforming growth factors-β1 and insulin-like growth factor-1) can enhance the rate of bone formation and synthesis of extracellular matrix in orthopaedics or periodontology. This study aimed to determine the concentration of cytokines within platelet-rich fibrin microstructures and investigate whether there are differences in the different portions of platelet-rich fibrin, which has implications for proper clinical use of platelet-rich fibrin gel. METHODS: Whole blood was obtained from six New Zealand rabbits (male, 7 to 39 weeks old, weight 2.7-4 kg); it was then centrifuged for preparation of platelet-rich fibrin gels and harvest of plasma. The resultant platelet-rich fibrin gels were used for cytokine determination, histological analyses and scanning electron microscopy. All plasmas obtained were subject to the same cytokine determination assays for the purpose of comparison. RESULTS: Cytokines platelet-derived growth factor-BB and transforming growth factor-β1 formed concentration gradients from high at the red blood cell end of the platelet-rich fibrin gel (p=1.88×10-5) to low at the plasma end (p=0.19). Insulin-like growth factor-1 concentrations were similar at the red blood cell and plasma ends. The porosities of the platelet-rich fibrin samples taken in sequence from the red blood cell end to the plasma end were 6.5% ± 4.9%, 24.8% ± 7.5%, 30.3% ± 8.5%, 41.4% ± 12.3%, and 40.3% ± 11.7%, respectively, showing a gradual decrease in the compactness of the platelet-rich fibrin network. CONCLUSION: Cytokine concentrations are positively associated with platelet-rich fibrin microstructure and portion in a rabbit model. As platelet-rich fibrin is the main entity currently used in regenerative medicine, assessing cytokine concentration and the most valuable portion of PRF gels is essential and recommended to all physicians.

Does platelet activity play a role in the pathogenesis of idiopathic ischemic priapism?

ABSTRACT Purpose Mean platelet volume (MPV) is used to measure platelet size and is defined as a potential marker of platelet reactivity. Higher MPV levels have been defined as a risk factor for increased incidence of intravascular thrombosis and its associated diseases. We aimed to determine whether a relationship exists between the MPV and veno-occlusive component of idiopathic ischemic priapism (IIP). Materials and methods Between 2010 and 2014, 38 subjects were analyzed in two groups. One was composed of 15 patients with diagnosis as IIP in our institute, and the other contained 23 healthy control subjects. Complete blood count reports were retrospectively evaluated in both groups. MPV, platelet count (PLT), platelet distribution width (PDW), white blood cells (WBC), red blood cells (RBC), hemoglobin (Hb), reticulocyte distribution width (RDW) were measured in both groups. : Results The mean ages were similar in IIP patients (45.86±15.82) and control subjects (47.65±10.99). The mean MPV values of IIP patients were significantly higher than control subjects (p<0.05). In contrast, also PLT counts were significantly lower in IIP patients, compared to control subjects (p<0.05). The mean hemoglobin and WBC values were significantly lower in control group (p<0.05). There was no significant difference of RBC, PDW and RDW values in both groups. Conclusions We found that the MPV was significantly higher in IIP patients compared to control subjects. The high MPV levels may have contributed to the veno-occlusive etiopathogenesis of IIP disease. We strongly suggest further prospective studies to recommend the use of MPV in routine practice.

A Pilot Study to Evaluate the Effectiveness of Carica Papaya Leaf Extract in Increasing the Platelet Count in Cases of Dengue with Thrombocytopenia.

The pilot study was conducted to investigate the platelet increasing property of Carica papaya leaf extract (CPLE) in patients with dengue fever (DF). An open labeled randomized controlled trial was carried out at two centres of Bangalore metropolis on 30 subjects in patients with thrombocytopenia associated with dengue. The subjects were randomized into two groups, as control and intervention group. Both the groups were managed by the standard management guidelines for dengue except steroid administration. In addition to this, the intervention group received CPLE tablet three times daily for five days. All of them were followed daily with platelet monitoring. The results showed that CPLE had significant increase in the platelet count (p<0.003) over the therapy duration, in dengue fever patients, reiterating that it accelerates the increase in platelet count compared to the control group. There were few adverse events related to GI disturbance like nausea and vomiting which were similar in both groups. Thus this study concluded that Carica papaya leaf extract (CPLE) does significantly increase the platelet count in patients with thrombocytopenia associated with dengue with fewer side effects and good tolerability.

Bone neoformation in defects treated with plateletrich fibrin membrane versus collagen membrane: a histomorphometric study in rabbit femurs / Neoformación ósea de defectos tratados con membrana de fibrina rica en plaquetas versus membrana de colágeno: un estudio histomorfométrico en fémur de conejos

The aim of the present research was to compare bone neoformation in bone defects treated with platelet-rich fibrin (PRF) and collagen membrane (CM) at 3 and 5 weeks. For this purpose, two bone defects with a width of 4 mm and depth of 6 mm were created in the left distal femur diaphysis of New Zealand rabbits (n=12). The subjects were randomly allocated into two groups. One of the defects was covered with a platelet-rich fibrin membrane (Centrifuged resorbable autologous blood biopolymer without biochemical modification) or a collagen membrane (gold standard - Neo Mem). The second defect was left uncovered (NC). The rabbits were sacrificed after 3 and 5 weeks (3 rabbits per period). The femur was completely removed and processed histomophometrically. The bone neformation analysis was performed using a differential point-counting method. Data was statistically analyzed (ANOVA, Tukey). The histomorphometric results showed that bone neformation in the defects treated with PRF at 3 weeks was equivalent to the CM (p<0.05). After 5 weeks, bone neformation obtained with PRF was higher than the control group and lower compared with the CM (p<0.05). The conclusion of the present study is that bone neformation in defects treated with PRF showed lower histomorphometric results compared with the one obtained with the collagen membrane and higher when compared with the control defects...

El objetivo de la investigación fue comparar la neoformación ósea de defectos óseos tratados con membrana de fibrina rica en plaquetas (PRF) y membrana de colágeno (CM), a las 3 y 5 semanas para lo cual se crearon dos defectos óseos de 4 mm de diámetro y 6 mm de profundidad en la diáfisis femoral distal izquierda de conejos Nueva Zelanda (n=12). Los animales fueron divididos aleatoriamente en 2 grupos. Uno de los defectos fue cubierto con membrana de fibrina rica en plaquetas (Biopolímero Reabsorbible Autólogo de sangre Centrifugada sin modificación bioquímica) o membrana de colágeno (Gold estándar-Neo Mem,) mientras que el segundo defecto se dejó sin cubrir (NC). Los conejos fueron sacrificados después de 3 y 5 semanas (3 conejos/periodo), se les extrae el fémur por desarticulación, se procesa y evalúa histomorfométricamente. El análisis de la neoformación ósea histológica fue realizado mediante el conteo diferencial de puntos. Los datos fueron analizados estadísticamente (ANOVA, Tukey). Los resultados histomorfométricos mostraron que la neoformación ósea de los defectos tratados con PRF a las 3 semanas fue equivalente a la neoformación obtenida en el grupo control y menor comparado con la neoformación del CM (p<0,05). A las 5 semanas la neoformación ósea obtenida con PRF fue mayor a la neoformación del grupo control y menor a la CM (p<0,05). Concluyendo que la neoformación ósea obtenida en los defectos tratados con PRF mostraron resultados histomorfométricos menores a la neoformación obtenida con colágeno y mayores en comparación a la neoformación de los defectos controles...

Isolated biomolecules of pharmacological interest in hemostasis from Cerastes cerastes venom

Biomolecules from Cerastes cerastes venom have been purified and characterized. Two phospholipases isolated from Cerastes cerastes venom share 51% of homology. CC2-PLA2 exhibits antiplatelet activity that blocks coagulation. CCSV-MPase, a non-hemorrhagic Zn2+-metalloproteinase, significantly reduced the plasmatic fibrinogen level and hydrolyzes only its Bß chain. Serine proteinases such as RP34, afaâcytin and CC3-SPase hydrolyze the fibrinogen and are respectively α, αß and αß fibrinogenases. In deficient human plasma, afaâcytin replaces the missing factors VIII and IX, and activates purified human factor X into factor Xa. It releases serotonin from platelets and directly aggregates human (but not rabbit) blood platelets. RP34 proteinase also had no effect on both human and rabbit blood platelet aggregation. CC3-SPase revealed a pro-coagulant activity. However, the insolubility of the obtained clot indicates that CC3-SPase does not activate factor XIII. In addition, CC3-SPase clotting activity was carried out with human plasmas from volunteer patients deficient in clotting factors. Results showed that CC3-SPase shortens clotting time of plasma deficient in factors II and VII but with weaker clotting than normal plasma. The clotting time of plasma deficient in factor II is similar to that obtained with normal plasma; suggesting that CC3-SPase is able to replace both factors IIa and VII in the coagulation cascade and thus could be involved in the blood clotting process via an extrinsic pathway. These results imply that CC3-SPase and afaâcytin could repair hemostatic abnormalities and may replace some factors missing in pathological deficiency. Afaâcytin also exhibits α fibrinase property similar to a plasmin-like proteinase. Despite its thrombin-like characteristics, afaâcytin is not inhibited by plasmatic thrombin inhibitors. The procoagulant properties of afaâcytin might have potential clinical applications.(AU)

Aplicación local de lisado plaquetario en úlceras posflebíticas / Local application of platelet lysate on posflebitic ulcers

El tratamiento de las úlceras postrombóticas o posflebíticas constituye un reto para la medicina debido a su cronicidad y a sus frecuentes recidivas que condicionan múltiples trastornos locales y sistémicos, con una mala calidad de vida del paciente. En este trabajo se incluyeron 80 pacientes con úlceras posflebíticas en miembros inferiores que fueron divididos en 2 grupos: 40 tratados con lisados de plaquetas alogénicas conservadas y 40 tratados convencionalmente, que conformaron el grupo control. Se consideró como buen resultado cuando a los 30 días de tratamiento o antes, el paciente presentó una respuesta parcial o total. En el 95 por ciento de los enfermos tratados con el lisado se obtuvo una buena respuesta (suma de las totales y parciales) contra el 75 por ciento en el grupo control (p>0,001). El uso del lisado plaquetario resultó un proceder simple y efectivo en el tratamiento de úlceras posflebíticas en miembros inferiores, que puede ser recomendado, ya que los pacientes pueden mantenerse en sus hogares y así se elimina el costo hospitalario que generalmente tiene el tratamiento de este tipo de lesión

Treatment of post-thrombotic ulcers or postflebitic is a challenge to medicine because of its chronicity and frequent recurrences that determine multiple local and systemic disorders with poor quality of life for patients. This study included 80 patients with lower limb posflebitic ulcers, who were grouped into 2 groups: 40 treated with preserved allogeneic platelet lysates and 40 were treated conventionally. The latter was the control group. It was considered good result when the patient had a partial or complete response after 30 days of treatment or before. Good response was found in 95 percent of patients treated with lysate (sum of total and partial values) versus 75 percent in the control group (p> 0.001). The use of platelet lysate was a simple and effective procedure in the treatment of lower limb posflebitic ulcers. This treatment can be recommended, since patients can stay at home, thus eliminating the hospital costs incurred in this type of treatment