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BACKGROUND: The prevalence of breast cancer (BC) is high among cancers in Egypt, ranking it the most common cause of cancer mortality in women. BRCA1 and BRCA2 tumor suppressors proteins have a specific relationship with BC. Plasma free amino acids levels (PFAAs) have been reported to exhibit altered profiles among cancer patients. Thus, the present study aims to examine the alteration of the PFAAs profiles and investigate their association with BRCA1 and 2 circulating levels in Egyptian females diagnosed with BC and in females with family history of BC to establish potential early detection strategies for BC. METHODS AND RESULTS: This study included 26 BC patients, 22 females with family history of BC (relatives) in addition to 38 healthy females as control group. Quantitative measurement of PFAAs was determined by the ion exchange separation method through high performance liquid chromatography. BRCA1 and BRCA2 concentrations were determined using ELISA. Our results showed PFAAs profiles in BC patients and in females with BC family history with significant upregulation in mean plasma levels of Alanine, Phenylalanine, Glutamate and Cysteine and downregulation of Taurine, Threonine, Serine, Glycine, Valine, Methionine and Histidine levels compared to controls. Also, a significant positive correlation was observed between plasma BRCA1 and Valine levels while a significant negative correlation was observed between BRCA2 and Lysine plasma levels. CONCLUSION: PFAAs profile can potentially be used in early screening for BC patients and for susceptible females.
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Aminoácidos , Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Regulação para Cima , Ácido Glutâmico , Valina , Proteína BRCA1/genéticaRESUMO
Despite the interwoven nature of platelet activation and the coagulation system in thrombosis, few studies relate both analysis of protein and cellular parts of coagulation in the same population. In the present study, we use matched ex vivo samples to determine the influences of standard antiplatelet therapies on platelet function and use advanced rheological analyses to assess clot formation. Healthy volunteers were recruited following fully informed consent then treated for 7 days with single antiplatelet therapy of aspirin (75 mg) or prasugrel (10 mg) or with dual antiplatelet therapy (DAPT) using aspirin (75 mg) plus prasugrel (10 mg) or aspirin (75 mg) plus ticagrelor (90 mg). Blood samples were taken at day 0 before treatment and at day 7 following treatment. We found that aspirin plus prasugrel or aspirin plus ticagrelor inhibited platelet responses to multiple agonists and reduced P-selectin expression. Significant platelet inhibition was coupled with a reduction in fractal dimension corresponding to reductions in mean relative mass both for aspirin plus prasugrel (-35 ± 16% change, p = 0.04) and for aspirin plus ticagrelor (-45 ± 14% change, p = 0.04). Aspirin alone had no effect upon measures of clot structure, whereas prasugrel reduced fractal dimension and mean relative mass. These data demonstrate that platelets are important determinants of clot structure as assessed by fractal dimension (df) and that effective platelet inhibition is associated with a weaker, more permeable fibrin network. This indicates a strong association between the therapeutic benefits of antiplatelet therapies and their abilities to reduce thrombus density that may be useful in individual patients to determine the functional relationship between platelet reactivity, eventual clot quality, and clinical outcome. df could represent a novel risk stratification biomarker useful in individualizing antiplatelet therapies.
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Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Trombose/metabolismo , Feminino , Fractais , Humanos , MasculinoRESUMO
BACKGROUND: There is a link between high on-treatment platelet reactivity (HPR) and adverse vascular events in stroke. This study aimed to compare multiple electrode platelet aggregometry (MEA), in healthy subjects and ischaemic stroke patients, and between patients naive to antiplatelet drugs (AP) and those on regular low dose AP. We also aimed to determine prevalence of HPR at baseline and at 3-5 days after loading doses of aspirin. METHODS: Patients with first ever ischaemic stroke were age and sex-matched to a healthy control group. Three venous blood samples were collected: on admission before any treatment given (baseline); at 24 h and 3-5 days after standard treatment. MEA was determined using a Mutliplate® analyser and agonists tested were arachidonic acid (ASPI), adenosine diphosphate (ADP) and collagen (COL). RESULTS: Seventy patients (mean age 73 years [SD 13]; 42 men, 28 women) were age and sex-matched to 72 healthy subjects. Thirty-three patients were on antiplatelet drugs (AP) prior to stroke onset and 37 were AP-naive. MEA results for all agonists were significantly increased in AP-naive patients compared to healthy subjects: ADP 98 ± 31 vs 81 ± 24, p < 0.005; ASPI 117 ± 31 vs 98 ± 27, p < 0.005; COL 100 ± 25 vs 82 ± 20, p < 0.005. For patients on long term AP, 33% (10/30) of patients were considered aspirin-resistant. At 3-5 days following loading doses of aspirin, only 11.1% were aspirin resistant based on an ASPI cut-off value of 40 AU*min. CONCLUSIONS: Many patients receiving low dose aspirin met the criteria of aspirin resistance but this was much lower at 3-5 days following loading doses of aspirin. Future studies are needed to establish the causes of HPR and potential benefits of individualizing AP treatment based on platelet function testing.
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Aspirina/uso terapêutico , Plaquetas/fisiologia , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/sangue , Idoso , Idoso de 80 Anos ou mais , Eletrodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos , Testes de Função Plaquetária , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
This study compared patients with venous thromboembolism (VTE) to non-VTE patients using a biomarker of clot microstructure (df ) and clot formation time (TGP ). df was the only marker that identified a significant difference (P < 0·001) between the VTE (n = 60) and non-VTE cohorts (n = 69). The 'abnormal' clot microstructures in the VTE patients suggests either inadequate response to anticoagulant therapy or the presence of a procoagulant state not detected by other markers of coagulation (i.e., International Normalized Ratio). Furthermore, elevated values of df in first time VTE patients who later develop a secondary event indicates that df may identify those at risk of recurrence.
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Testes de Coagulação Sanguínea , Técnicas de Imagem por Elasticidade , Hemorreologia , Tromboembolia Venosa/sangue , Idoso , Anticoagulantes/uso terapêutico , Biomarcadores/sangue , Feminino , Fibrina/análise , Fibrinólise , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Tromboembolia Venosa/tratamento farmacológico , Substâncias Viscoelásticas , Varfarina/uso terapêuticoRESUMO
BACKGROUND: Stroke is the second largest cause of death worldwide. Hypercoagulability is a key feature in ischaemic stroke due to the development of an abnormally dense clot structure but techniques assessing the mechanics and quality of clot microstructure have limited clinical use. We have previously validated a new haemorheological technique using three parameters to reflect clot microstructure (Fractal Dimension (d f )) ex-vivo, real-time clot formation time (T GP ) and blood clot strength (elasticity at the gel point (G'GP)). We aimed to evaluate these novel clotting biomarkers in ischaemic stroke and changes of clot structure following therapeutic intervention. METHODS: In a prospective cohort study clot microstructure was compared in ischaemic stroke patients and a control group of healthy volunteers. Further assessment took place at 2-4 hours and at 24 hours after therapeutic intervention in the stroke group to assess the effects of thrombolysis and anti-platelet therapy. RESULTS: 75 patients (mean age 72.8 years [SD 13.1]; 47 male, 28 female) with ischaemic stroke were recruited. Of the 75 patients, 32 were thrombolysed with t-PA and 43 were loaded with 300 mg aspirin. The following parameters were significantly different between patients with stroke and the 74 healthy subjects: d f (1.760 ± .053 versus 1.735 ± 0.048, p = 0.003), TGP (208 ± 67 versus 231 ± 75, p = 0.05), G'GP (0.056 ± 0.017 versus 0.045 ± 0.014, p < 0.0001) and fibrinogen (3.7 ± 0.8 versus 3.2 ± 0.5, p < 0.00001). There was a significant decrease in d f (p = 0.02), G'GP (p = 0.01) and fibrinogen (p = 0.01) following the administration of aspirin and for d f (p = 0.003) and fibrinogen (p < 0.001) following thrombolysis as compared to baseline values. CONCLUSION: Patients with ischaemic stroke have denser and stronger clot structure as detected by d f and G'GP. The effect of thrombolysis on clot microstructure (d f ) was more prominent than antiplatelet therapy. Further work is needed to assess the clinical and therapeutic implications of these novel biomarkers.
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Elasticidade , Fractais , Acidente Vascular Cerebral/sangue , Trombose/sangue , Tempo de Coagulação do Sangue Total , Idoso , Idoso de 80 Anos ou mais , Aspirina/uso terapêutico , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Fibrinogênio/metabolismo , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Trombose/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêuticoRESUMO
BACKGROUND: Stroke is the second largest cause of death worldwide. Abnormalities in hemostasis play an important role in the pathophysiology of ischemic stroke (IS). These hemostatic defects can be detected using rotational thromboelastometry (ROTEM) as a global method of measuring coagulation. This study assessed the effects of IS on blood hypercoagulability using ROTEM method, before and subsequent to therapeutic interventions. METHODS: In a prospective observational cohort study, whole blood coagulation using ROTEM, along with full blood count and standard coagulation tests, were compared between patients with IS and an age-matched control group of healthy volunteers. Further assessment took place at 2-4 hours and at 24 hours in the stroke group after therapy to assess the effects of therapeutic intervention. RESULTS: Seventy-two patients with IS were age-matched to 71 healthy subjects. Clotting time (CT) INTEM (P = .01) and maximum clot firmness (MCF) INTEM (P = .02) were significantly different between stroke patients at baseline and healthy subjects, but this difference disappeared when controlled for by smoking status. There was no association between ROTEM parameters and time from stroke symptom onset or stroke severity as reflected in The National Institute of Health Stroke Scale score. Significant but small changes in the values of MCF-EXTEM, clot formation time (CFT) EXTEM, and alpha-EXTEM CT were observed after therapeutic intervention (thrombolysis or aspirin treatment). CONCLUSIONS: ROTEM testing does not seem to detect a hypercoagulable state in patients with IS. Nonetheless, some ROTEM parameters had a small change after antiplatelet therapy or thrombolysis.
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Coagulação Sanguínea/fisiologia , Isquemia Encefálica/sangue , Acidente Vascular Cerebral/sangue , Tromboelastografia/métodos , Terapia Trombolítica , Idoso , Idoso de 80 Anos ou mais , Aspirina/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do TratamentoRESUMO
Introduction The purpose of this study was to determine the prevalence of ventricular tachycardia (VT) among patients admitted with peripartum cardiomyopathy (PPCM) as well as to analyze the independent association of VT with in-hospital outcomes among PPCM patients. Methods Data were obtained from the National Inpatient Sample from January 2016 to December 2019. We assessed predictors of VT in patients admitted with PPCM. We also assessed the independent association of VT with clinical outcomes among patients admitted with PPCM. Results From 2016 to 2019, 4730 patients with PPCM were reported to the national inpatient sample database, 309 of which developed VT (6.5%). Using multivariate analysis, we found predictors of VT to include patient characteristics and factors such as age (adjusted OR (aOR)=1.020, p=0.023), chronic kidney disease (aOR=1.440, p=0.048), coagulopathy (aOR=1.964, p=0.006), and atrial fibrillation (aOR=3.965, p<0.001). Conversely, pre-eclampsia was significantly associated with a decreased risk of VT in PPCM patients (aOR=0.218, p=0.001). Conclusion In a large cohort of patients admitted with peripartum cardiomyopathy, we found the prevalence of VT to be 6.5%. Risk factors for VT in this patient population included conditions such as coagulopathy and atrial fibrillation.
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OBJECTIVES: Cardiac surgery for coronary artery disease was dramatically reduced during the first wave of the COVID-19 pandemic. Many patients with disease ordinarily treated with coronary artery bypass grafting (CABG) instead underwent percutaneous coronary intervention (PCI). We sought to describe 12-month outcomes following PCI in patients who would typically have undergone CABG. METHODS: Between March 1 and July 31, 2020, patients who received revascularization with PCI when CABG would have been the primary choice of revascularization were enrolled in the prospective, multicenter UK-ReVasc Registry. We evaluated the following major adverse cardiovascular events at 12 months: all-cause mortality, myocardial infarction, repeat revascularization, stroke, major bleeding, and stent thrombosis. RESULTS: A total of 215 patients were enrolled across 45 PCI centers in the United Kingdom. Twelve-month follow up data were obtained for 97% of the cases. There were 9 deaths (4.3%), 5 myocardial infarctions (2.4%), 12 repeat revascularizations (5.7%), 1 stroke (0.5%), 3 major bleeds (1.4%), and no cases of stent thrombosis. No difference in the primary endpoint was observed between patients who received complete vs incomplete revascularization (residual SYNTAX score £ 8 vs > 8) (P = .22). CONCLUSIONS: In patients with patterns of coronary disease in whom CABG would have been the primary therapeutic choice outside of the pandemic, PCI was associated with acceptable outcomes at 12 months of follow-up. Contemporary randomized trials that compare PCI to CABG in such patient cohorts may be warranted.
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BACKGROUND: Unfavourable clot microstructure is associated with adverse outcomes in ST elevation myocardial infarction (STEMI). We investigated the effect of comorbidities and anti-platelet treatment on clot microstructure in STEMI patients using fractal dimension (df), a novel biomarker of clot microstructure derived from the visco-elastic properties of whole blood. METHODS: Patients with STEMI (n = 187) were recruited sequentially receiving aspirin with Clopidogrel (n = 157) then Ticagrelor (n = 30). Patient characteristics and blood for rheological analysis obtained. We quantified df using sequential frequency sweep tests to obtain the phase angle of the Gel Point which is synonymous with the clot microstructure. RESULTS: Higher df was observed in males (1.755 ± 0.068) versus females (1.719 ± 0.061, p = .001), in patients with diabetes (1.786 ± 0.067 vs 1.743 ± 0.046, p < .001), hypertension (1.760 ± 0.065 vs 1.738 ± 0.069, p = .03) and previous MI (1.787 ± 0.073 vs 1.744 ± 0.066, p = .011) compared to without. Patients receiving Ticagrelor had lower df than those receiving Clopidogrel (1.708 ± 0.060 vs 1.755 ± 0.067, p < .001). Significant correlation with df was found with haematocrit (r = 0.331, p < .0001), low-density lipoprotein (LDL) (r = 0.155, p = .046) and fibrinogen (r = 0.182, p = .014). Following multiple regression analysis, diabetes, LDL, fibrinogen and haematocrit remained associated with higher df while treatment with Ticagrelor remained associated with lower df. CONCLUSIONS: The biomarker df uniquely evaluates the effect of interactions between treatment and underlying disease on clot microstructure. STEMI patients with diabetes and elevated LDL had higher df, indicating denser clot. Ticagrelor resulted in a lower df than Clopidogrel signifying a less compact clot.
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Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Trombose , Masculino , Feminino , Humanos , Ticagrelor/uso terapêutico , Clopidogrel/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Infarto do Miocárdio com Supradesnível do Segmento ST/tratamento farmacológico , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Trombose/etiologia , Biomarcadores , Fibrinogênio , Resultado do Tratamento , Intervenção Coronária Percutânea/efeitos adversosRESUMO
During the growing season of 2021-2022, a total of 145 symptomatic tomato leaf and fruit samples were collected from different locations in Riyadh Region, Saudi Arabia, showing a moderate-to-severe mosaic with dark green wrinkling, blistering, narrowing, and deformation with necrosis spot on tomato leaves, while irregular brown necrotic lesions, deformation, and yellowing spots rendering the fruits non-marketable were observed on tomato fruits. These samples were tested serologically against important tomato viruses using enzyme-linked immunosorbent assay (ELISA), and the obtained results showed that 52.4% of symptomatic tomato samples were found positive for Tomato brown rugose fruit virus (ToBRFV), wherein 12 out of 76 samples were singly infected; however, 64 out of 145 had mixed infection. A sample with a single infection of ToBRFV was used for mechanical inoculation into a range of different host plants; symptoms were observed weekly, and the presence of the ToBRFV was confirmed by ELISA and reverse transcription-polymerase chain reaction (RT-PCR). A total RNA was extracted from selected ELISA-positive samples, and RT-PCR was carried out using specific primers F-3666 and R-4718, which amplified a fragment of 1052 bp. RT-PCR products were sequenced in both directions, and partial genome nucleotide sequences were submitted to GenBank under the following accession numbers: MZ130501, MZ130502, and MZ130503. BLAST analysis of Saudi isolates of ToBRFV showed that the sequence shared nucleotide identities (99-99.5%) among them and 99-100% identity with ToBRFV isolates in different countries. A ToBRFV isolate (MZ130503) was selected for mechanical inoculation and to evaluate symptom severity responses of 13 commonly grown tomato cultivars in Saudi Arabia. All of the tomato cultivars showed a wide range of symptoms. The disease severity index of the tested cultivars ranged between 52% and 96%. The importance ToBRFV disease severity and its expanding host range due to its resistance breaking ability was discussed.
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Meningococcal disease is a global burden and remains one of the leading infectious causes of death in children, with an estimated annual death rate of 170,000 worldwide. Despite these figures, the management of children with severe meningococcal sepsis and septic shock remains suboptimal. This review presents an overview of this condition including the epidemiology, pathogenesis, clinical manifestations, complications, management, and prediction.
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Meningite Meningocócica/epidemiologia , Meningite Meningocócica/terapia , Criança , Saúde Global , Humanos , Meningite Meningocócica/prevenção & controle , Infecções Meningocócicas , Neisseria meningitidis/classificação , Neisseria meningitidis/patogenicidade , Prevenção Primária , Fatores de Risco , Sepse/microbiologia , Resultado do TratamentoRESUMO
INTRODUCTION: This aim of this study is to investigate the individual effects of varying concentrations of thrombin and fibrinogen on clot microstructure (characterised through the fractal dimension of the incipient clot network, df) and clot formation time (TGP) using a fibrin-thrombin clot model. df and TGP markers are measured using a haemorheological method that has already been investigated for whole blood. METHODS: This is an in vitro study using three thrombin concentrations (0.1, 0.05 and 0.02 NIH/ml) and two fibrinogen concentrations (8âmg/ml and 12âmg/ml) to investigate a fibrin-thrombin clot model. The haemorheological changes were measured at the gel point using df and TGP. RESULTS: Fractal dimension (df) increased with increasing concentrations of thrombin both at 8âmg/ml (1.60±0.024, 1.67±0.022, 1.74±0.079) and 12âmg/ml fibrinogen concentrations (1.63±0.02, 1.87±0.019, 1.95±0.014). On the other hand, TGP decreased for both 8âmg/ml (1089±265, 637±80, 223±22 seconds) and 12âmg/ml fibrinogen concentrations (2008±247, 776±20, 410±20 seconds). In contrast to previous studies investigating whole blood, TGP increased with higher fibrinogen levels. CONCLUSIONS: The findings from this fibrin-thrombin clot model confirmed that df and TGP can detect changes in the incipient clot following manipulation of fibrinogen and thrombin concentration. df increases (indicating stronger clot) with higher concentrations of thrombin and fibrinogen. On the other hand, TGP decreased as expected with higher thrombin level but not with higher fibrinogen concentrations.
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Testes de Coagulação Sanguínea/métodos , Coagulação Sanguínea/efeitos dos fármacos , Fibrina/metabolismo , Trombina/metabolismo , Trombose/fisiopatologia , HumanosRESUMO
Multilineage-differentiating stress-enduring (Muse) cells are a population of pluripotent stage-specific embryonic antigen 3 (SSEA3)+ mesenchymal stem cells first described by Mari Dezawa in 2010. Although some investigators have reported SSEA3+ mesenchymal cells in umbilical cord tissues, none have quantitatively compared SSEA3+ cells isolated from Wharton's jelly (WJ) and the cord lining (CL) of human umbilical cords (HUCs). We separated WJ and the CL from HUCs, cultured mesenchymal stromal cells (MSCs) isolated from these two tissues with collagenase, and quantified the percentage of SSEA3+ cells over three passages. The first passage had 5.0% ± 4.3% and 5.3% ± 5.1% SSEA3+ cells from WJ and the CL, respectively, but the percentage of SSEA3+ cells decreased significantly (P < 0.05) between P0 and P2 in the CL group and between P0 and P1 in the WJ group. Magnetic-activated cell sorting (MACS) markedly enriched SSEA3+ cells to 91.4% ± 3.2%. Upon culture of the sorted population, we found that the SSEA3+ percentage ranged from 62.5% to 76.0% in P2-P5 and then declined to 42.0%-54.7% between P6 and P9. At P10, the cultures contained 37.4% SSEA3+ cells. After P10, we resorted the cells and achieved 89.4% SSEA3+ cells in culture. The procedure for MACS-based enrichment of SSEA3+ cells, followed by expansion in culture and a re-enrichment step, allows the isolation of many millions of SSEA3+ cells in relatively pure culture. When cultured, the sorted SSEA3+ cells differentiated into embryoid spheres and survived 4 weeks after transplant into a contused Sprague-Dawley rat spinal cord. The transplanted SSEA3+ cells migrated into the injury area from four injection points around the contusion site and did not produce any tumors. The umbilical cord is an excellent source of fetal Muse cells, and our method allows the practical and efficient isolation and expansion of relatively pure populations of SSEA3+ Muse cells that can be matched by human leukocyte antigen for transplantation in human trials.
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Antígenos Glicosídicos Associados a Tumores/metabolismo , Células-Tronco Mesenquimais/citologia , Traumatismos da Medula Espinal/metabolismo , Antígenos Embrionários Estágio-Específicos/metabolismo , Cordão Umbilical/citologia , Animais , Diferenciação Celular , Células Cultivadas , Humanos , Ratos , Ratos Sprague-Dawley , Geleia de Wharton/citologiaRESUMO
BACKGROUND: Coronary artery disease (CAD) is associated with an increased prothrombotic tendency and is also linked to unfavourably altered clot microstructure. We have previously described a biomarker of clot microstructure (df) that is unfavourably altered in acute myocardial infarction. The df biomarker assesses whether the blood will form denser or looser microstructures when it clots. In this study we assessed in patients with stable chest pain whether df can differentiate between obstructed and unobstructed CAD. METHODS: A blood sample prior to angiography was obtained from 251 consecutive patients undergoing diagnostic coronary angiography. Patients were categorised based on angiographic findings as presence or absence of obstructive CAD (stenosis ≥50%). The blood sample was assessed using the df biomarker, standard laboratory markers and platelet aggregometry (Multiplate). RESULTS: A significant difference (p=0.028) in df was observed between obstructive CAD (1.748±0.057, n=83) and unobstructive CAD (1.732±0.052, n=168), where patients with significant CAD produce denser, more tightly packed clots. df was also raised in men with obstructive CAD compared with women (1.745±0.055 vs 1.723±0.052, p=0.007). Additionally df significantly correlated with the platelets response to arachidonic acid as measured by the ASPItest area under the curve readings from platelet aggregometry (correlation coefficient=0.166, p=0.008), a low value of the ASPItest indicating effective aspirin use was associated with looser, less dense clots. CONCLUSIONS: For the first time, we characterise clot microstructure, as measured by df, in patients with stable CAD. df can potentially be used to risk-stratify patients with stable CAD and assess the efficacy of therapeutic interventions by measuring changes in clot microstructure.
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OBJECTIVES: Changes in clot microstructure are increasingly implicated in the pathology of atherosclerosis although most data are from techniques in the remote laboratory using altered blood. We validate the novel biomarker Gel Point in STEMI patients and assess therapeutic interventions. Gel Point marks the transition of blood from a visco-elastic liquid to visco-elastic solid and is rapidly measured using unadulterated blood. The Gel Point provides measurements of three parameters to reflect clot microstructure (fractal dimension (df)), real-time clot formation time (TGP) and blood clot strength (elasticity at the Gel Point (G'GP)). METHODS: We prospectively recruited 38 consecutive patients with STEMI undergoing primary percutaneous coronary intervention (pPCI). Venous blood samples were collected on admission, after pPCI and 24 h after admission for assessment of the new biomarkers, standard coagulation tests and scanning electron microscopy (SEM). RESULTS: df after pPCI was lower than df on admission (mean 1.631 [SD 0.063] vs 1.751 [0.052], p < 0.000001) whereas df at 24 h was similar to that on admission. G'GP also showed similar trend to df (p < 0.001). TGP was prolonged at after-PCI measurement compared with admission (median 854 s [IQR 581-1801] vs 217 [179-305], p < 0.00001). Changes in the values of df and G'GP were consistent with changes in the SEM images of the mature clot. CONCLUSIONS: We characterise Gel Point derived markers of clot microstructure in patients admitted with emergency arterial thrombosis. This point of care test can potentially be used to assess the efficacy of therapeutic interventions by measuring changes in clot microstructure.
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Testes de Coagulação Sanguínea/métodos , Coagulação Sanguínea , Trombose Coronária/diagnóstico , Fractais , Infarto do Miocárdio/diagnóstico , Testes Imediatos , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Angiografia Coronária , Trombose Coronária/sangue , Trombose Coronária/terapia , Elasticidade , Estudos de Viabilidade , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Masculino , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Agregação Plaquetária , Inibidores da Agregação Plaquetária/uso terapêutico , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , ViscosidadeRESUMO
INTRODUCTION: We investigated the effect of progressive haemodilution on the dynamics of fibrin clot formation and clot microstructure using a novel rheological method. The technique measures clotting time (TGP), clot strength (G`GP), and quantifies clot microstructure (df) at the incipient stages of fibrin formation. We use computational modelling to examine the relationship between structure and mass, as well as helium ion microscopy (HIM) to compare morphological changes in the fully formed clot to that of the incipient clot. METHODS: This is an in vitro study; 90 healthy volunteers were recruited with informed consent and a 20ml sample of whole blood obtained from each volunteer. Five clinically relevant dilutions were investigated using 0.9w.v isotonic saline (0, 10, 20, 40 and 60%, n=18 for each dilution). The rheological method of assessing structural clot changes was compared against conventional coagulation screen and fibrinogen estimation. RESULTS: Fractal dimension (df) and final clot microstructure both decreased with progressive dilution (significant at a dilution of 20%) with similar relationships observed for final clot characteristics in HIM images. Significant correlations were observed between df and G`GP (clot strength) (0.345, p=0.02), as well as clotting time (PT: -0.690, p>0.001; APTT: -0.672, p>0.001; TGP: -0.385, p=0.006). CONCLUSIONS: This study provides new insight into the effects of haemodilution by isotonic saline on clotting time (TGP), clot strength (G'GP) and clot microstructure (df). Previous studies have attempted to link clot microstructure to clot quality/strength, however this study provides a significant step in quantifying these relationships.