Antithrombotic and anticariogenic activity of peptide fractions from cowpea (Vigna unguiculata) protein hydrolysates.

BACKGROUND: Protein-derived peptide fractions can play a key role in the physiological and metabolic regulation and modulation of the body, which suggests that they could be used as functional ingredients to improve health and to reduce the risk of disease. This work aimed to evaluate the in vitro antithrombotic and anticariogenic bioactivity of hydrolysates and protein fractions obtained from cowpea (Vigna unguiculata) by biocatalysis. RESULTS: Cowpea protein concentrate was hydrolyzed by sequential action with two enzyme systems, Pepsin-Pancreatin or Alcalase-Flavourzyme. There was extensive enzymatic hydrolysis, with degrees of hydrolysis of 34.94% and 81.43% for Pepsin-Pancreatin and Alcalase-Flavourzyme, respectively. The degree of hydrolysis for the control treatments, without the addition of the enzymes Pepsin-Pancreatin and Alcalase-Flavourzyme was 1.1% and 1.2%, respectively. The hydrolysates were subjected to fractionation by ultrafiltration, with five cut-off points according to molecular weight (<1, 1-3, 3-5, 5-10 and >10 kDa). The Alcalase-Flavourzyme hydrolysate led to 100% inhibition of platelet aggregation, while the Pepsin-Pancreatin hydrolysate showed 77.41% inhibition, but this was approximately 100% in the ultrafiltered fractions. The highest anticariogenic activity was obtained with the Pepsin-Pancreatin system, with 61.55% and 56.07% for calcium and phosphorus demineralization, respectively. CONCLUSION: Hydrolysates and their peptide fractions from Vigna unguiculata exhibited inhibition of platelet aggregation and protection of tooth enamel and have the potential for use in the development of functional products with beneficial health effects. © 2024 Society of Chemical Industry.

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.

Janus kinase inhibitors modify the fatty acid profile of extracellular vesicles and modulate the immune response.

Background: Janus kinase inhibitors (jakinibs) are immunomodulators used for treating malignancies, autoimmune diseases, and immunodeficiencies. However, they induce adverse effects such as thrombosis, lymphocytosis, and neutropenia that could be mediated by extracellular vesicles (EVs). These particles are cell membrane-derived structures that transport cellular and environmental molecules and participate in intercellular communication. Jakinibs can modify the content of EVs and enable them to modulate the activity of different components of the immune response. Objective: to evaluate the interactions between immune system components of healthy individuals and EVs derived from monocytic and lymphoid lineage cells generated in the presence of baricitinib (BARI) and itacitinib (ITA) and their possible effects. Methods: EVs were isolated from monocytes (M) and lymphocytes (L) of healthy individuals, as well as from U937 (U) and Jurkat (J) cells exposed to non-cytotoxic concentrations of BARI, ITA, and dimethyl sulfoxide (DMSO; vehicle control). The binding to and engulfment of EVs by peripheral blood leukocytes of healthy individuals were analyzed by flow cytometry using CFSE-stained EVs and anti-CD45-PeCy7 mAb-labeled whole blood. The effect of EVs on respiratory burst, T-cell activation and proliferation, cytokine synthesis, and platelet aggregation was evaluated. Respiratory burst was assessed in PMA-stimulated neutrophils by the dihydrorhodamine (DHR) test and flow cytometry. T-cell activation and proliferation and cytokine production were assessed in CFSE-stained PBMC cultures stimulated with PHA; expression of the T-cell activation markers CD25 and CD69 and T-cell proliferation were analyzed by flow cytometry, and the cytokine levels were quantified in culture supernatants by Luminex assays. Platelet aggregation was analyzed in platelet-rich plasma (PRP) samples by light transmission aggregometry. The EVs' fatty acid (FA) profile was analyzed using methyl ester derivatization followed by gas chromatography. Results: ITA exposure during the generation of EVs modified the size of the EVs released; however, treatment with DMSO and BARI did not alter the size of EVs generated from U937 and Jurkat cells. Circulating neutrophils, lymphocytes, and monocytes showed a 2-fold greater tendency to internalize ITA-U-EVs than their respective DMSO control. The neutrophil respiratory burst was attenuated in greater extent by M-EVs than by L-EVs. Autologous ITA-M-EVs reduced T-cell proliferation by decreasing IL-2 levels and CD25 expression independently of CD69. A higher accumulation of pro-inflammatory cytokines was observed in PHA-stimulated PBMC cultures exposed to M-EVs than to L-EVs; this difference may be related to the higher myristate content of M-EVs. Platelet aggregation increased in the presence of ITA-L/M-EVs by a mechanism presumably dependent on the high arachidonic acid content of the vesicles. Conclusions: Cellular origin and jakinib exposure modify the FA profile of EVs, enabling them, in turn, to modulate neutrophil respiratory burst, T-cell proliferation, and platelet aggregation. The increased T-cell proliferation induced by BARI-L/M-EVs could explain the lymphocytosis observed in patients treated with BARI. The higher proportion of arachidonic acid in the FA content of ITA-L/M-EVs could be related to the thrombosis described in patients treated with ITA. EVs also induced a decrease in the respiratory burst of neutrophils.

Antiplatelet mechanism of a subtilisin-like serine protease from Solanum tuberosum (StSBTc-3).

The aims of this study are to characterize the antiplatelet activity of StSBTc-3, a potato serine protease with fibrino (geno) lytic activity, and to provide information on its mechanism of action. The results obtained show that StSBTc-3 inhibits clot retraction and prevents platelet aggregation induced by thrombin, convulxin, and A23187. Platelet aggregation inhibition occurs in a dose-dependent manner and is not affected by inactivation of StSBTc-3 with the inhibitor of serine proteases phenylmethylsulfonyl fluoride (PMSF). In addition, StSBTc-3 reduces fibrinogen binding onto platelets. In-silico calculations show a high binding affinity between StSBTc-3 and human α2bß3 integrin suggesting that the antiplatelet activity of StSBTc-3 could be associated with the fibronectin type III domain present in its amino acid sequence. Binding experiments show that StSBTc-3 binds to α2bß3 preventing the interaction between α2bß3 and fibrinogen and, consequently, inhibiting platelet aggregation. StSBTc-3 represents a promising compound to be considered as an alternative to commercially available drugs used in cardiovascular therapies.

Migraña poscierre percutáneo de defectos septales auriculares / Migraine after percutaneous closure of atrial septal defects / Enxaqueca após fechamento percutâneo de comunicação interatrial

La migraña es una enfermedad que se ha visto asociada a defectos septales auriculares y a su cierre percutáneo, estipulándose en la literatura que sería una rara complicación, pero la evidencia al respecto es escasa. Se realizó una revisión narrativa sobre definiciones, epidemiología, fisiopatología y tratamiento de la migraña y de la entidad migraña poscierre percutáneo de defectos del septum auricular, incluyendo trabajos observacionales (retrospectivos, prospectivos), estudios randomizados, reportes de casos, artículos de revisión y metaanálisis existentes en PubMed y Cochrane, para aportar al conocimiento de esta entidad.

Migraine is a disease that has been associated with atrial septal defects and its percutaneous closure, stipulating in the literature that it would be a rare complication, but evidence is scarce. A narrative review was conducted on definitions, epidemiology, pathophysiology and treatment of migraine and the migraine entity after percutaneous closure of atrial septum defects, including observational studies (retrospective, prospective), randomized studies, case reports, review articles and meta-analyses existing in PubMed and Cochrane, to contribute to the knowledge of this entity.

A enxaqueca é uma doença que tem sido associada a defeitos do septo atrial e seu fechamento percutâneo, estipulando na literatura que seria uma complicação rara, mas as evidências são escassas. Foi realizada uma revisão narrativa sobre definições, epidemiologia, fisiopatologia e tratamento da enxaqueca e da entidade migranosa após fechamento percutâneo de defeitos do septo atrial, incluindo estudos observacionais (retrospectivos, prospectivos), estudos randomizados, relatos de caso, artigos de revisão e metanálises existentes no PubMed e Cochrane, para contribuir com o conhecimento dessa entidade.

Serotonin secretion by blood platelets: accuracy of high-performance liquid chromatography-electrochemical technique compared with the isotopic test and use in a clinical laboratory.

Background: Mild secretion defects are the most frequent and challenging blood platelet disorders to diagnose. Most δ-granule secretion tests lack validation, are not quantitative, or have unreliable response to weak platelet agonists. Objectives: To compare platelet serotonin secretion by HPLC-electrochemical detection technique (HPLC-ECD) with the reference isotopic test (3H-5-HT), evaluating its performance in clinical laboratories. Methods: The assay validation followed STARD-2015 recommendations. HPLC-ECD measured the nonsecreted serotonin remaining in platelet pellets after aggregation, comparing it with the reference 3H-5-HT assay. We studied subjects with inherited and aspirin-induced blood platelet disorders and assessed the HPLC-ECD operation for routine clinical diagnosis. Results: Calibration curves were linear (R2 = 0.997), with SD for residuals of 3.91% and analytical sensitivity of 5ng/mL. Intra- and interassay imprecision bias ranged between -8.5% and 2.1% and -9% and 3.1%, respectively. Serotonin recovery and stability were >95%, and the variability range of measurements was -5.5% to 4.6%. Statistical differences detected between tests were biologically irrelevant, with bias of 1.48% (SD, 8.43) and CI agreement of -18% to 15%. Both assays distinctly detected platelet secretion induced by 10 µM epinephrine and 4 µmM adenosine diphosphate. However, HPLC-ECD is quantitative and more sensitive to low serotonin content in blood platelets. Reference cutoffs for each agonist were determined in 87 subjects. Initially, the HPLC-ECD requires relatively expensive equipment and trained operators but has remarkably cheap running costs and a turn-around time of 24-36 hours. We have used this diagnostic tool routinely for >8 years. Conclusion: HPLC-ECD assay for platelet serotonin secretion is highly accurate, has advantages over the reference 3H-5-HT test, and is suitable as a clinical laboratory technique.

Mouse skin peptidomic analysis of the hemorrhage induced by a snake venom metalloprotease.

Hemorrhage induced by snake venom metalloproteases (SVMPs) results from proteolysis, capillary disruption, and blood extravasation. HF3, a potent SVMP of Bothrops jararaca, induces hemorrhage at pmol doses in the mouse skin. To gain insight into the hemorrhagic process, the main goal of this study was to analyze changes in the skin peptidome generated by injection of HF3, using approaches of mass spectrometry-based untargeted peptidomics. The results revealed that the sets of peptides found in the control and HF3-treated skin samples were distinct and derived from the cleavage of different proteins. Peptide bond cleavage site identification in the HF3-treated skin showed compatibility with trypsin-like serine proteases and cathepsins, suggesting the activation of host proteinases. Acetylated peptides, which originated from the cleavage at positions in the N-terminal region of proteins in both samples, were identified for the first time in the mouse skin peptidome. The number of peptides acetylated at the residue after the first Met residue, mostly Ser and Ala, was higher than that of peptides acetylated at the initial Met. Proteins cleaved in the hemorrhagic skin participate in cholesterol metabolism, PPAR signaling, and in the complement and coagulation cascades, indicating the impairment of these biological processes. The peptidomic analysis also indicated the emergence of peptides with potential biological activities, including pheromone, cell penetrating, quorum sensing, defense, and cell-cell communication in the mouse skin. Interestingly, peptides generated in the hemorrhagic skin promoted the inhibition of collagen-induced platelet aggregation and could act synergistically in the local tissue damage induced by HF3.

Adaptive changes in redox response and decreased platelet aggregation in lead-exposed workers.

Chronic lead exposure can generate pro-oxidative and pro-inflammatory conditions in the blood, related to high platelet activation and aggregation, altering cell functions. We studied ADP-stimulated aggregation and the oxidant/antioxidant system of platelets from chronically lead-exposed workers and non-exposed workers. Platelet aggregation was low in lead-exposed workers (62 vs. 97%), who had normal platelet counts and showed no clinical manifestations of hemostatic failure. ADP-activated platelets from lead-exposed workers failed to increase superoxide release (3.3 vs. 6.6 µmol/g protein), had low NADPH concentration (60 vs. 92 nmol/mg protein), high concentration of hydrogen peroxide (224 vs. 129 nmol/mg protein) and high plasma PGE2 concentration (287 vs. 79 pg/mL). Altogether, those conditions, on the one hand, could account for the low platelet aggregation and, on the other, indicate an adaptive mechanism for the oxidative status of platelets and anti-aggregating molecules to prevent thrombotic problems in the pro-oxidant and pro-inflammatory environment of chronic lead exposure.

Antithrombotic regimens for the prevention of major adverse cardiac events in chronic coronary syndrome: A systematic review and network meta-analysis.

Backgroud: Antithrombotic therapy is the cornerstone of chronic coronary syndrome (CCS) management. However, the best treatment option that optimally balances bleeding risk and efficacy remains undefined. Our objective was to evaluate the effectiveness and safety of antithrombotic options and identify the optimal treatment option for patients with CCS. Methods: We used the MEDLINE, CENTRAL and Embase databases to search for randomized controlled trials with follow-up periods longer than 12 months that compared aspirin (ASA) monotherapy with other antithrombotic therapies in patients with CCS. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used. Extracted data [hazard ratios (HR)] were pooled using Bayesian fixed-effect models, allowing the estimation of credible intervals (CrI) and posterior probabilities of benefit, harm, and practical equivalence. Confidence in the results was assessed with the Confidence In Network Meta-Analysis (CINeMA) tool. The primary efficacy and safety outcomes were major adverse cardiovascular events (MACE) and primary bleeding, respectively. Secondary outcomes were acute myocardial infarction, ischemic stroke, all-cause, and cardiovascular-specific mortality. Results: Five trials with a total of 80,605 patients were included. Mean patient age ranged from 61 to 69 years, while 20.3% to 31.4% were women. The reference treatment was ASA monotherapy. ASA + prasugrel 10 mg and clopidogrel 75 mg monotherapy presented the greatest benefit for MACE [HR 0.52 (95% CrI, 0.39-0.71); and 0.68 (95% CrI, 0.54-0.88)]. There was a probability of 98.8% that ASA + ticagrelor was practically equivalent to ASA monotherapy. Regarding the primary bleeding outcome, clopidogrel 75 mg monotherapy performed best [HR 0.64 (0.42, 0.99)]. There was a probability of 97.4% that ASA + Prasugrel 10 mg increases bleeding (HR > 1.0). Secondary outcome results followed a similar treatment ranking pattern as in primary outcomes. Overall, CINeMA confidence ratings were judged as either low or very low. Conclusions: These results revealed that clopidogrel monotherapy might provide the best risk-benefit balance in treating CCS. However, low CINeMA confidence ratings may preclude more forceful conclusions. Our analysis suggests that current guidelines recommending ASA as first-line therapy for CCS management need to be revised to include additional pharmacological options.

The role of CYP2C9*2, CYP2C9*3 and VKORC1-1639 variants on the susceptibility of upper gastrointestinal bleeding: A full case-control study.

Purpose: To investigate whether interindividual variability in the CYP2C9 (*2 and *3 alleles) and VKORC1 (rs9923231) genes is associated with increased risk of upper gastrointestinal bleeding (UGIB) in users of non-steroidal anti-inflammatory drugs (NSAIDs) or low-dose aspirin (LDA). Methods: A full case-control study including 200 cases of patients diagnosed with UGIB and 706 controls was conducted in a Brazilian hospital complex. To perform an analysis of NSAIDs dose-effect, the defined daily dose (DDD) for NSAIDs was calculated in the 7-day etiologic window preceding the data index. Three categories of DDD, considering the genotypes of the genetic variants, were established: non-users of NSAIDs (DDD = 0), DDD ≤0.5, and DDD >0.5. Genetic variants and LDA or NSAIDs use synergism was estimated through Synergism Index (SI) and Relative Excess Risk Due To Interaction (RERI). Results: For DDDs of NSAIDs upward of 0.50, a risk of UGIB was identified in carriers of the *3 allele (OR: 15,650, 95% CI: 1.41-174.10) and in carriers of the variant homozygous genotype (TT) of rs9923231 (OR: 38,850, 95% CI: 2.70-556.00). In LDA users, the risk of UGIB was observed to be similar between carriers of the wild type homozygous genotype and carriers of the variant alleles for the CYP2C9 and VKORC1 genes. No synergism was identified. Conclusion: Our findings suggest an increased risk of UGIB in carriers of the variant allele of rs9923231 and in carriers of the *3 allele associated with doses of NSAIDs greater than 0.5. Hence, the assessment of these variants might reduce the incidence of NSAIDs-related UGIB and contribute to the safety of the NSAIDs user.

Mouse skin peptidomic analysis of the hemorrhage induced by a snake venom metalloprotease

Hemorrhage induced by snake venom metalloproteases (SVMPs) results from proteolysis, capillary disruption, and blood extravasation. HF3, a potent SVMP of Bothrops jararaca, induces hemorrhage at pmol doses in the mouse skin. To gain insight into the hemorrhagic process, the main goal of this study was to analyze changes in the skin peptidome generated by injection of HF3, using approaches of mass spectrometry-based untargeted peptidomics. The results revealed that the sets of peptides found in the control and HF3-treated skin samples were distinct and derived from the cleavage of different proteins. Peptide bond cleavage site identification in the HF3-treated skin showed compatibility with trypsin-like serine proteases and cathepsins, suggesting the activation of host proteinases. Acetylated peptides, which originated from the cleavage at positions in the N-terminal region of proteins in both samples, were identified for the first time in the mouse skin peptidome. The number of peptides acetylated at the residue after the first Met residue, mostly Ser and Ala, was higher than that of peptides acetylated at the initial Met. Proteins cleaved in the hemorrhagic skin participate in cholesterol metabolism, PPAR signaling, and in the complement and coagulation cascades, indicating the impairment of these biological processes. The peptidomic analysis also indicated the emergence of peptides with potential biological activities, including pheromone, cell penetrating, quorum sensing, defense, and cell–cell communication in the mouse skin. Interestingly, peptides generated in the hemorrhagic skin promoted the inhibition of collagen-induced platelet aggregation and could act synergistically in the local tissue damage induced by HF3.

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.

Platelet Reactivity and Inflammatory Phenotype Induced by Full-Length Spike SARS-CoV-2 Protein and Its RBD Domain.

A state of immunothrombosis has been reported in COVID-19. Platelets actively participate in this process. However, little is known about the ability of SARS-CoV-2 virus proteins to induce platelet activity. Platelet-rich plasma (PRP) was incubated with spike full-length protein and the RBD domain in independent assays. We evaluated platelet activation through the expression of P-selectin and activation of glicoprotein IIbIIIa (GP IIbIIIa), determined by flow cytometry and the ability of the proteins to induce platelet aggregation. We determined concentrations of immunothrombotic biomarkers in PRP supernatant treated with the proteins. We determined that the spike full-length proteins and the RBD domain induced an increase in P-selectin expression and GP IIbIIIa activation (p < 0.0001). We observed that the proteins did not induce platelet aggregation, but favored a pro-aggregating state that, in response to minimal doses of collagen, could re-establish the process (p < 0.0001). On the other hand, the viral proteins stimulated the release of interleukin 6, interleukin 8, P-selectin and the soluble fraction of CD40 ligand (sCD40L), molecules that favor an inflammatory state p < 0.05. These results indicate that the spike full-length protein and its RBD domain can induce platelet activation favoring an inflammatory phenotype that might contribute to the development of an immunothrombotic state.

The addition of Tirofiban infusión to heparin for intraoperative heparin resistance associated with Marfan Syndrome / Adición de una infusión de Tirofiban a heparina en caso de resistencia intraoperatoria a la heparina asociada al Síndrome de Marfan

Abstract Marfan syndrome classically presents with aortic root aneurysms. Aortic ectasia causes diverse blood flow alterations, influencing the behavior of coagulation factors and platelet activity. Heparin resistance has also been reported associated with Marfan Syndrome in a small number of patients, probably due to antithrombin III (ATIII) deficiency or various mutations. The ascending aorta and the aortic valve are replaced with prosthetic material during Bentall- de Bonno procedures. Resistance to anticoagulation during extracorporeal circulation, represents a significant challenge for both anesthesiologists and the surgical team. Resistance to heparin was observed in a patient with Marfan syndrome undergoing a Bentall procedure. ATIII concentrate was not available, and Activated Coagulation Time did not increase despite high doses of heparin. An alternate anticoagulation approach was used successfully.

Resumen El síndrome de Marfan clásicamente se presenta con aneurismas de la raíz de la aorta. La ectasia aórtica produce alteraciones en el flujo sanguíneo que influyen sobre el comportamiento de los factores de la coagulación y la actividad de las plaquetas. También se ha reportado resistencia a la heparina asociada al Síndrome de Marfan en un menor número de pacientes, probablemente debido a deficiencia de antitrombina III (ATIII) o a diversas mutaciones. La aorta ascendente y la válvula aórtica se reemplazan con material prostético en los procedimientos Bentall- de Bonno. La resistencia a la anticoagulación durante circulación extracorpórea significa un enorme desafío tanto para los anestesiólogos, como para el equipo quirúrgico. Se observó resistencia a la heparina en un paciente con Síndrome de Marfan sometido a un procedimiento de Bentall. No había disponibilidad de concentrado ATIII y no aumentó el Tiempo de Coagulación Activada a pesar de las elevadas dosis de heparina. Se utilizó exitosamente un abordaje alterno de anticoagulación.

Quantification of cyclic AMP and cyclic GMP levels in Krebs-Henseleit solution by LC-MS/MS: Application in washed platelet aggregation samples.

Cyclic Nucleotides are important in regulating platelet function. Increases in 3'5'-cyclic adenosine monophosphate (cAMP) and 3'5'-cyclic guanosine monophosphate (cGMP) inhibit platelet aggregation and are pharmacological targets for antiplatelet therapy. Here we report an improved method for determining cAMP and cGMP concentrations and, for the first time, in washed platelet supernatants by combining high-performance liquid chromatography and tandem mass spectrometry (LC-MS/MS). Characteristic peaks of the substrates, cGMP or cAMP and their internal standards were identified in negative-ion electrospray ionisation using multiple reaction monitoring. Compared with previously reported methods, the method presented here shows high precision with the lowest lower limit of quantification (LLoQ) to date (10 pg/mL). The effect of a novel catecholamine, 6-nitrodopamine, on cyclic nucleotide levels was quantified. Our results showed that this new method was fast, sensitive, and highly reproducible.

Drogas antiagregantes plaquetárias e anticoagulantes em pacientes que se submeterão à cirurgia oral: conduta / Antiagregant platelet and anticoagulant drugs in patients who will submit oral surgery: conduct

Objetivo: Como a frequência de pacientes em uso de anticoagulantes e antiagragantes plaquetários nos consultórios odontológicos é crescente, este trabalho objetivou avaliar através de Revisão de Literatura, qual o melhor manejo desses medicamentos na prática odontológica perioperatória. Metodologia: Trata-se de uma revisão integrativa da literatura, utilizadas as bases de dados Scielo e PubMed. Foram escolhidos os seguintes descritores disponíveis na BVs e PubMed em inglês "Platelet Aggregation Inhibitors", "Oral Surgical Procedures" e "Antigoagulants" no período de 2016 a 2021. Também foram consultados livros e sites de diretrizes do Governo. Foram escolhidos 20 artigos para elaboração da pesquisa. Resultados: doenças cardiovasculares e outras condições clínicas pró-coagulantes tem prevalência crescente e são conhecidos fatores de risco para a ocorrência de fenômenos tromboembólicos graves. A terapia antitrombótica tem papel definido nesses casos. No perioperatorio de cirurgias orais, a decisão por suspender ou manter a terapia deve ser individualizada e pode ser orientada por guidelines. Conclusão: procedimentos orais de baixo risco de sangramento podem ser conduzidos sem a descontinuação da terapia antitrombótica. Cirurgias de moderado a alto risco frequentemente requerem suspensão temporária das medicações para fins de minimizar os riscos de complicações hemorrágicas... (AU)

Objective: As the frequency of patients using anticoagulants and antiplatelet agents in dental offices is increasing, this study aimed to evaluate, through a Literature Review, which is the best management of these medications in dental perioperative practice. Methodology: This is an integrative literature review, being used Scielo and PubMed databases. The following descriptors available in BVs and PubMed "Platelet aggregation inhibitors", "Oral Surgical Procedures" and "Antigoagulants" were used, from 2016 to 2021. In addition, the search was also performed in guideline books and Government websites. Twenty articles were chosen for research elaboration. Results: established cardiovascular disease and other procoagulant clinical conditions have an increasing prevalence, especially among the elderly, and are known risk factors for the occurrence of severe thromboembolic phenomena. Antithrombotic therapy has defined role in these cases. In the perioperative period of oral surgery, the decision to suspend or maintain therapy must be individualized and may be guided by guidelines. Age appears as a clinical criterion in the main ones used. Conclusion: oral procedures with low risk of bleeding can be carried out without discontinuing antithrombotic therapy. Moderate to high-risk surgeries usually require its temporary suspension in order to minimize the risk of bleeding complications... (AU)

Effects of Baru Almond Oil (Dipteryx alata Vog.) Treatment on Thrombotic Processes, Platelet Aggregation, and Vascular Function in Aorta Arteries.

Background: This study assessed the effects of Baru (Dipteryx alata Vog.) almond oil supplementation on vascular function, platelet aggregation, and thrombus formation in aorta arteries of Wistar rats. Methods: Male Wistar rats were allocated into three groups. The control group (n = 6), a Baru group receiving Baru almond oil at 7.2 mL/kg/day (BG 7.2 mL/kg, n = 6), and (iii) a Baru group receiving Baru almond oil at 14.4 mL/kg/day (BG 14.4 mL/kg, n = 6). Baru oil was administered for ten days. Platelet aggregation, thrombus formation, vascular function, and reactive oxygen species production were evaluated at the end of treatment. Results: Baru oil supplementation reduced platelet aggregation (p < 0.05) and the production of the superoxide anion radical in platelets (p < 0.05). Additionally, Baru oil supplementation exerted an antithrombotic effect (p < 0.05) and improved the vascular function of aorta arteries (p < 0.05). Conclusion: The findings showed that Baru oil reduced platelet aggregation, reactive oxygen species production, and improved vascular function, suggesting it to be a functional oil with great potential to act as a novel product for preventing and treating cardiovascular disease.

Human Platelets Contain, Translate, and Secrete Azurocidin; A Novel Effect on Hemostasis.

Platelets play a significant role in hemostasis and perform essential immune functions, evidenced by the extensive repertoire of antimicrobial molecules. Currently, there is no clear description of the presence of azurocidin in human platelets. Azurocidin is a 37 kDa cationic protein abundant in neutrophils, with microbicidal, opsonizing, and vascular permeability-inducing activity. Therefore, this work aimed to characterize the content, secretion, translation, and functions of azurocidin in platelets. Our results show the presence of azurocidin mRNA and protein in α-granules of platelet and megakaryoblasts, and stimulation with thrombin, ADP, and LPS leads to the secretion of free azurocidin as well as within extracellular vesicles. In addition, platelets can translate azurocidin in a basal or thrombin-induced manner. Finally, we found that the addition of low concentrations of azurocidin prevents platelet aggregation and activation. In conclusion, we demonstrate that platelets contain, secrete, and translate azurocidin, and this protein may have important implications for hemostasis.

Síndrome de vena cava superior: una serie de casos consecutivos en pacientes internados en un hospital terciario universitario / Superior vena cava syndrome: a consecutive case series of in-hospital patients in a tertiary teaching hospital

Introducción: el síndrome de vena cava superior resulta de la obstrucción del flujo sanguíneo a través de este vaso. Casi la totalidad de los casos en la actualidad se asocian con tumores malignos. Existen controversias acerca del manejo apropiado de este cuadro. Actualmente, las terapias endovasculares son consideradas de elección. Materiales y métodos: se recolectaron y describieron, a partir de datos de la historia clínica electrónica, los casos de pacientes mayores de 18 años internados ­de forma consecutiva, que desarrollaron el síndrome­ en el Hospital Italiano de Buenos Aires en 2021. Se constataron las características basales, los tratamientos recibidos y los desenlaces clínicos intrahospitaliarios de cada uno de ellos. Resultados: un total de cinco pacientes fueron incluidos en el presente estudio y seguidos durante su instancia intrahospitalaria. Todos los casos descriptos fueron secundarios a enfermedades oncológicas. La mayoría de los pacientes presentaron un cuadro de moderada gravedad según las escalas utilizadas. En cuatro de cinco pacientes se optó por terapias endovasculares y dos de ellos fallecieron durante la internación. Discusión: existen controversias respecto del tratamiento óptimo del síndrome de vena cava superior, y heterogeneidad en la práctica clínica. Los estudios futuros deberían centrarse en identificar a aquellos pacientes que más probablemente se beneficien de las estrategias terapéuticas endovasculares, anticoagulantes o antiagregantes. (AU)

Introduction: superior vena cava syndrome results from an obstruction of blood flow through this vessel. Currently, almost all cases are associated with malignancies. There are controversies about the optimal management of this syndrome. Endovascular therapies are considered the first-line therapy. Material and methods: we collected clinical, laboratory and pharmacological data from patients admitted at the Hospital Italiano de Buenos Aires, between January 1st and November 1st 2021 with a diagnosis o superior vein cava syndrome. Baseline characteristics, treatment strategies and clinical outcomes were recorded. Results: a total of five patients were included in the present study. All cases were malignancy-related. Most of the patientsdeveloped moderate symptoms. Four out of five patients were treated with endovascular therapies and two patients died during hospitalization. Discussion: controversies regarding optimal management of the superior vena cava syndrome remain. Future research should focus on identifying those patients who are most likely to benefit from endovascular, anticoagulant or antiplatelet therapeutic strategies. (AU)

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.