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1.
Res Pract Thromb Haemost ; 8(1): 102294, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38292349

RESUMO

Background: Venomous snake bites have been listed as a neglected tropical disease by the World Health Organization. The Mozambique spitting cobra (Naja mossambica) is found in Sub-Saharan African countries, and its venom has been identified to predominantly result in cytotoxic effects. However, there is limited evidence on the possible hemotoxic effects of this venom on human blood. Objectives: In this cross-sectional study, we investigated how Mozambique spitting cobra venom affects blood clot formation. Methods: Cell morphology and clot architecture were studied by using microscopy techniques. We also studied the effects of the venom on platelets by measuring platelet activity with the global thrombosis test, followed by analyzing the viscoelasticity with thromboelastography using a 0.025 ng/µL venom concentration. Results: The most prominent findings indicated that the viscoelastic profile in the venom-treated blood samples formed an unstable and elastic clot. The clot architecture seen with the scanning electron microscopy analysis showed an altered fibrin network and red blood cells, confirmed by the increased axial ratios, and aggregated platelets with spreading. Conclusion: These findings may offer insights into the species-specific effects of snake venom on human blood and add value to the clinical workup in confirming envenomation. Further research is needed to correlate the 20 minute whole blood clotting test with measurable values from the thromboelastography within the context of snake envenomation. This may offer a bridge between cost, early diagnosis, and treatment of snake envenomation in resource-constrained countries.

2.
Metabolites ; 13(10)2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37887417

RESUMO

Oral hormonal contraceptive users carry the risk of venous thrombosis and increased mortality. This study aimed to comprehensively profile the serum metabolome of participants using a combination of drospirenone (DRSP) and ethinyl estradiol (EE) containing oral contraceptives (COCs). The MxP Quant 500 kit for liquid chromatography mass tandem spectrometry (LC-MS/MS) was used to analyse the 22 controls and 44 COC users (22 on a low EE dose (DRSP/20EE) and 22 on a higher EE dose (DRSP/30EE)). The kit's results were compared to our internally developed untargeted and targeted metabolomics methods previously applied to this cohort. Of the 630 metabolites included in the method, 277 provided desirable results (consistently detected above their detection limits), and of these, 5 had p-values < 0.05, including betaine, glutamine, cortisol, glycine, and choline. Notably, these variations were observed between the control and COC groups, rather than among the two COC groups. Partial least squares-discriminant analysis revealed 49 compounds with VIP values ≥ 1, including amino acids and their derivatives, ceramides, phosphatidylcholines, and triglycerides, among others. Ten differential compounds were consistent with our previous studies, reinforcing the notion of COCs inducing a prothrombotic state and increased oxidative stress. Although only a limited number of compounds were deemed usable, these were quantified with high reliability and facilitated the identification of meaningful biological differences among the sample groups. In addition to substantiating known drug-induced variations, new hypotheses were also generated.

3.
Front Physiol ; 13: 899629, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784888

RESUMO

Higher thrombotic burden in the acute phase of COVID-19 relies on a complex interplay between pro-inflammatory cytokine/chemokine release, increased endothelial dysfunction/damage, and potential sepsis-induced coagulopathy development in severe cases, all promoting coagulation activation. Plasma levels of cytokines and chemokines are known to be increased in COVID-19 however, are much higher in severe infections. Increased levels of IL-1ß, IL-6, and IL-8 are known to play an important role in both acute and chronic inflammation, resulting in pathological clotting. However, little has been published on the effects of these interleukins on red blood cells (RBCs). Evidence shows that cytokines have a negative effect on the RBCs ultrastructure and introduce signs of eryptosis. Eryptosis can be described as a form of suicidal death of RBCs characterized by distinct findings of cell shrinkage, membrane blebbing, activation of proteases, and phosphatidylserine exposure at the outer membrane leaflet. Red blood cells from COVID-19 patients had increased levels of glycolytic intermediates, accompanied by oxidation and fragmentation of ankyrin, spectrin beta, and the N-terminal cytosolic domain of band 3 (AE1). Significantly altered lipid metabolism was also observed, in particular, short- and medium-chain saturated fatty acids, acyl-carnitines, and sphingolipids. Emerging research suggests that RBCs may contribute to a precision medicine approach to sepsis and have diagnostic value in monitoring complement dysregulation in COVID-19-sepsis and non-COVID sepsis as research indicates that complement activation products and viral antigens are present on RBCs in patients with COVID-19.

5.
Clin Hemorheol Microcirc ; 81(3): 221-232, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35253736

RESUMO

BACKGROUND: Increased risk of thromboembolic events is associated with prostate cancer, specifically linked to activation of tissue factor. Vitamin D has potential anticoagulant effects by the downregulation of tissue factor expression. OBJECTIVES: To evaluate the effects on clot formation, the morphological and viscoelastic profiles of prostate cancer patients, before and after ex vivo supplementation of Vitamin D was studied. METHODS: Participants were recruited into a metastatic, non-metastatic and reference group. Whole blood samples were treated ex vivo with a dose of 0.5µg/kg Calcitriol. Clot kinetics were assessed using Thromboelastography®. Morphology of the blood components were studied using scanning electron microscopy (SEM). RESULTS: Results from the Thromboelastography® and SEM indicated no major differences between the non-metastatic group before and after treatment compared to the reference group. The Thromboelastography® showed that the metastatic group had an increased viscoelastic profile relating to a hypercoagulable state. Visible changes with regards to platelet activation and fibrin morphology were demonstrated with SEM analysis of the metastatic group. The viscoelastic and morphological properties for the non-metastatic group after treatment improved to be comparable to the reference group. CONCLUSION: Vitamin D supplementation may lead to a more favorable viscoelastic profile, with less dangerous clots forming.


Assuntos
Neoplasias da Próstata , Trombose , Suplementos Nutricionais , Fibrina/metabolismo , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Tromboelastografia , Tromboplastina , Trombose/tratamento farmacológico , Vitamina D/uso terapêutico
6.
Metabolomics ; 17(9): 75, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34409503

RESUMO

INTRODUCTION: Metabolome variations have long been associated with normal hormonal fluctuations, and similar effects, related to the use of early generation synthetic hormones as a means of contraception, have also been identified. OBJECTIVE: We investigated the serum amino acid and acylcarnitine profiles induced by the use of combined oral contraceptives (COCs) consisting of Ethinylestradiol (EE) and a 4th generation progestin, Drospirenone (DRSP). METHOD: Gas chromatography mass spectrometry and liquid chromatography with tandem mass spectrometry was used to identify and quantify the serum amino acids and acyl carnitine levels in 24 controls, 25 DRSP/20EE users and 26 DRSP/30EE users. RESULTS: Of the 26 amino acid compounds measured, 13 showed significant variations in abundance between the control and COC user groups. Although none of the 21 acylcarnitine compounds detected were statistically significant with regards to group variations, a trend, related the EE concentration, was observed. The detected metabolome disparities corresponded to that identified for earlier generation COCs, all pointing toward increased oxidative stress levels in the user groups. CONCLUSION: These findings suggest that the clinical complications associated with these COCs could, to some extent, be alleviated by the simultaneous use of antioxidants. The study also highlights the role that targeted metabolomics could play in the elucidation of the underlying mechanisms of drug-induced severe effects.


Assuntos
Anticoncepcionais Orais Combinados , Etinilestradiol , Aminoácidos , Androstenos , Carnitina/análogos & derivados , Feminino , Humanos
7.
Microsc Microanal ; 27(2): 425-436, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33526165

RESUMO

Breast cancer (BC) is one of the most prevalent forms of cancer in women worldwide. Clinical research indicates that BC patients are at an increased risk for thrombotic events, drastically decreasing their quality-of-life and treatment outcomes. There is ample evidence of this in the literature, but it is mainly focused on metastatic BC. Therefore, coagulopathies of nonmetastatic BC are understudied and require in-depth investigation. In this study, clot kinetics and ultrastructure were used to investigate treatment-naïve, nonmetastatic BC patients using scanning electron microscopy, Thromboelastography®, and confocal laser scanning microscopy. It was demonstrated that nonmetastatic BC patients exhibit minimal ultrastructural alterations of the clot components and no changes in the clot kinetics. However, BC patients presented changes to fibrinogen protein structure, compared to matched controls, using an amyloid-selective stain. Together, these findings suggest that coagulation dysfunction(s) in BC patients with early disease manifest at the microlevel, rather than the macrolevel. This study presents novel insights to a method that are more sensitive to coagulation changes in this specific patient group, emphasizing that the coagulation system may react in different forms to the disease, depending on the progression of the disease itself.


Assuntos
Neoplasias da Mama , Trombose , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Feminino , Fibrinogênio/análise , Humanos
8.
Microsc Microanal ; 26(5): 1007-1013, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32778190

RESUMO

Combined oral contraceptives (COCs) are commonly prescribed and increase the risk of venous thromboembolism (VTE). We have previously found that two COCs, both containing drospirenone (DRSP) and ethinyl estradiol (EE), cause spontaneous fibrin formation in whole blood. The aim of this study was, therefore, to use platelet-poor plasma (PPP) from the same cohort of DRSP/EE users to determine the impact of these COCs on the fibrin component, specifically the fibrin clot viscoelasticity, turbidimetry, and biophysical traits. PPP from 25 females per test group and a control group (n = 25) were analyzed using thromboelastography (TEG), turbidimetry, and scanning electron microscopy. The results highlight abnormal fibrin clot formation, lysis, and architecture; DRSP/20EE showed the greatest effect. DRSP/EE use increased the fibrin fiber diameter and showed dense matted clots. Only when the influence of COCs on the structural properties and behavior of fibrin fibers during thrombus formation and lysis is better understood are we able to predict and prevent coagulopathies associated with these synthetic hormones. Clinical practitioners should take this into consideration for female patients that either have comorbidities, which could burden the coagulation system, or may be exposed to external factors that could increase their risk for VTE.


Assuntos
Testes de Coagulação Sanguínea , Coagulação Sanguínea/efeitos dos fármacos , Anticoncepcionais Orais Combinados/farmacologia , Fibrina/química , Fibrina/ultraestrutura , Adolescente , Adulto , Androstenos , Etinilestradiol/farmacologia , Feminino , Fibrina/farmacologia , Humanos , Masculino , Microscopia Eletrônica de Varredura , Tromboelastografia , Trombose , Tromboembolia Venosa , Viscosidade , Adulto Jovem
9.
OMICS ; 24(7): 404-414, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32471328

RESUMO

The association between hypercoagulability and use of drospirenone (DRSP) and ethinylestradiol (EE) containing combined oral contraceptives (COCs) is an important clinical concern. We have previously reported that the two formulations of DRSP combined with EE (namely, DRSP/20EE and DRSP/30EE) bring about a prothrombotic state in hemostatic traits of female users. We report here the serum metabolomic changes in the same study cohort in relation to the attendant prothrombotic state induced by COC use, thus offering new insights on the underlying biochemical mechanisms contributing to the altered coagulatory profile with COC use. A total of 78 healthy women participated in this study and were grouped as follows: control group not using oral contraceptives (n = 25), DRSP/20EE group (n = 27), and DRSP/30EE group (n = 26). Untargeted metabolomics revealed changes in amino acid concentrations, particularly a decrease in glycine and an increase in both cysteine and lanthionine in the serum, accompanied by variations in oxidative stress markers in the COC users compared with the controls. Of importance, this study is the first to link specific amino acid variations, serum metabolites, and the oxidative metabolic profile with DRSP/EE use. These molecular changes could be linked to specific biophysical coagulatory alterations observed in the same individuals. These new findings lend evidence on the metabolomic substrates of the prothrombotic state associated with COC use in women and informs future personalized/precision medicine research. Moreover, we underscore the importance of an interdisciplinary approach to evaluate venous thrombotic risk associated with COC use.


Assuntos
Androstenos/efeitos adversos , Biomarcadores/sangue , Coagulação Sanguínea/efeitos dos fármacos , Anticoncepcionais Orais Combinados/efeitos adversos , Etinilestradiol/efeitos adversos , Metaboloma , Adolescente , Adulto , Androstenos/administração & dosagem , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Plaquetas/ultraestrutura , Anticoncepcionais Orais Combinados/administração & dosagem , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/ultraestrutura , Etinilestradiol/administração & dosagem , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Metabolômica/métodos , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Trombose/sangue , Trombose/diagnóstico , Trombose/etiologia , Adulto Jovem
10.
Front Neurol ; 10: 1262, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31849822

RESUMO

Introduction: Migraine is a debilitating primary headache disorder with a poorly understood aetiology. An extensive body of literature supports the theory of migraine as a systemic vascular inflammatory disorder characterised by endothelial dysfunction. It is also well-known that chronic inflammation results in an excessive burden of oxidative stress and therefore cellular dysfunction. In this study the effects of excessive oxidative stress through the phases of female migraine-with-aura (FMA) were evaluated by examining the health of the systems of haemostasis. Methods: Blood was obtained from 11 FMA patients at baseline and during the headache phase of migraine, as well as from 8 healthy age-matched female controls. Samples were analysed using thromboelastography (TEG) to evaluate viscoelastic profiles, light microscopy for erythrocyte morphology, Scanning Electron Microscopy (SEM) for erythrocyte and fibrin clot structure, confocal microscopy for ß-amyloid detection in fibrin clots. Results: Viscoelastic profiles from platelet poor plasma showed decreased clot reaction times in FMA at baseline (95% CI [5.56, 8.41]) vs. control (95% CI [7.22, 11.68]); as well as decreased time to maximum thrombus generation for the same comparison (95% CI [6.78, 10.20] vs. [8.90, 12.96]). Morphological analysis of erythrocytes indicated widespread macrocytosis, poikilocytosis and eryptosis in the migraineurs. Analysis of fibrin networks indicated that this hypercoagulability may be a result of aberrant fibrin polymerisation kinetics caused by the adoption of a ß-amyloid conformation of fibrin(ogen). Conclusion: The results reaffirm the hypercoagulable state in migraine, and would suggest that this state is most likely a result of a systemic inflammatory state which induces oxidative damage to both erythrocytes and fibrin(ogen) in female episodic migraine-with-aura. Furthermore, if the amylodogenic changes to fibrin(ogen) were observed in a larger cohort, this would support theories of micro-embolisation in migraine-with-aura.

11.
Microsc Microanal ; 24(6): 713-728, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30588913

RESUMO

Venous thrombosis is associated with combined oral contraceptive (COC) use. We investigated the impact of two ethinyl estradiol (EE) and drospirenone (DRSP) containing COCs (3 mg DRSP/20 µg EE and 3 µg DRSP/30 µg EE) on the viscoelasticity of whole blood clots along with the biophysical and biochemical characteristics of erythrocytes. Thromboelastography (TEG) analysis showed a tendency toward a hypercoagulable state in the COCs groups that was more pronounced with higher EE concentrations. Light microscopy and scanning electron microscopy (SEM) showed rouleaux formation of erythrocytes and alterations to the erythrocyte shape for both COC groups, which was attributed to membrane damage. SEM analysis showed spontaneous activation of fibrin and platelets in the COC groups, along with interactions between erythrocytes and platelets and/or fibrin. Confocal microscopy confirmed compromised membrane integrity in the COC groups compared to controls. Global thrombosis test analysis showed increased platelet activation and low thrombolysis in both COC groups when compared to controls. In conclusion, DRSP/EE formulations impact erythrocytes' biophysical and biochemical properties to cause a shift in hemostasis to a prothrombotic state. Although these effects are mostly subclinical the long-term effects and risks involved with the use of these hormones should be considered carefully for each individual.


Assuntos
Androstenos/farmacologia , Anticoncepcionais Orais Combinados/farmacologia , Módulo de Elasticidade/efeitos dos fármacos , Agregação Eritrocítica/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Etinilestradiol/farmacologia , Ativação Plaquetária/efeitos dos fármacos , Trombose Venosa/induzido quimicamente , Viscosidade/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Membrana Celular/fisiologia , Forma Celular/efeitos dos fármacos , Eritrócitos/química , Feminino , Humanos , Microscopia Eletrônica de Varredura , Tromboelastografia
12.
Microsc Res Tech ; 81(12): 1489-1500, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30365192

RESUMO

There are several possible mechanisms by which combined oral contraceptives (COC) use increase venous thromboembolism (VTE) risk. Melodene® is a monophasic COC containing the third-generation progestin Gestodene (GSD), which is associated with increased risk of VTE. Therefore, the aim of this study was to investigate the possible alterations in viscoelastic parameters of whole blood and plasma clots along with the biophysical characteristics of erythrocytes and specifically fibrin fibers in females using a COC containing GSD. GSD appeared to have a significant impact on the biophysical characteristics of fibrin fiber networks. When GSD is combined with ethinylestradiol the viscoelastic properties of whole blood clots tend to become more prothrombotic. The alterations to and aggregation of erythrocytes accompanied with spontaneous formation of a fibrin "blanket" provides a possible mechanism for the increased occurrence of "red" clots, which can lead to occlusions in the vascular system. Thus, the increased risk of VTE associated with these COCs can be attributed to these erythrocyte-and-fibrin-rich-clots occluding venous vessels. However, our findings also propose that these changes to the biophysical properties of both erythrocytes and fibrin, specifically spontaneous expansion of deformed fibrin networks, can also occlude vessels in the microcirculation, which could have lasting, subclinical complications for female users. We recommend that a thorough risk assessment, with specific focus on coagulation and other factors affecting fibrin formation, be done for each female before prescribing a GSD-containing COC. Females that "qualify" then need to be monitored on a regular basis to lower the risk of thrombotic events. RESEARCH HIGHLIGHTS: Gestodene in combination with ethinyl estradiol significantly impacts the biophysical characteristics of erythrocytes and fibrin fiber networks. These changes, specifically spontaneous expansion of deformed fibrin networks, can occlude vessels in the microcirculation, which could have lasting, subclinical complications for the female user. The changes observed for specifically erythrocytes and fibrin show that the hormone formulation investigated contribute to a thrombogenic profile for female users.


Assuntos
Anticoncepcionais Orais Combinados/efeitos adversos , Norpregnenos/efeitos adversos , Trombose/etiologia , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Fibrina/metabolismo , Humanos , Trombose/sangue , Trombose/metabolismo , Adulto Jovem
13.
Front Aging Neurosci ; 10: 257, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30186156

RESUMO

Many studies indicate that there is a (mainly dormant) microbial component in the progressive development of Alzheimer-type dementias (ADs); and that in the case of Gram-negative organisms, a chief culprit might be the shedding of the highly inflammagenic lipopolysaccharide (LPS) from their cell walls. We have recently shown that a highly sensitive assay for the presence of free LPS [added to platelet poor plasma (PPP)] lies in its ability (in healthy individuals) to induce blood to clot into an amyloid form. This may be observed in a SEM or in a confocal microscope when suitable amyloid stains (such as thioflavin T) are added. This process could be inhibited by human lipopolysaccharide-binding protein (LBP). In the current paper, we show using scanning electron microscopy and confocal microscopy with amyloid markers, that PPP taken from individuals with AD exhibits considerable amyloid structure when clotting is initiated with thrombin but without added LPS. Furthermore, we could show that this amyloid structure may be reversed by the addition of very small amounts of LBP. This provides further evidence for a role of microbes and their inflammagenic cell wall products and that these products may be involved in pathological clotting in individuals with AD.

14.
Clin Hemorheol Microcirc ; 69(4): 457-469, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29710680

RESUMO

BACKGROUND: Haemochromatosis is an iron-storage disease with different genetic mutations, characterized by an increased intestinal absorption of iron, resulting in a deposition of excessive amounts of iron in parenchymal cells. When the iron is released in the blood, it is left in an unliganded form, where it can participate in Haber-Weiss and Fenton reactions, creating hydroxyl radicals. Erythrocytes (RBCs) are particularly vulnerable to hydroxyl radical damage, which can result in eryptosis (programmed cell death similar to apoptosis). STUDY DESIGN AND METHODS: Here, we used flow cytometry to study the presence of eryptosis in the main genotypic variations of HFE (heterozygous and homozygous C282Y; H63D; C282Y/H63D). We also viewed RBCs from the different mutations using super-resolution Airyscan confocal microscopy. RESULTS: Flow cytometry showed significant changes in membrane biochemistry, indicated by the presence of phosphatidylserine (PS) proteins on the outer leaflet of the membrane, as well as increased intracellular calpain. This was found in all of the studied mutations. Airyscan fluorescence revealed PS flip and also microparticles from RBCs. Such microparticles are known to be pro-inflammatory. CONCLUSION: We conclude that RBC pathology is present in all the studied HFE mutations, even in low penetrance mutations, and this might affect rheology in these individuals.


Assuntos
Eriptose/genética , Hemocromatose/complicações , Microscopia Confocal/métodos , Reologia/métodos , Adulto , Feminino , Citometria de Fluxo , Hemocromatose/patologia , Humanos , Masculino , Pessoa de Meia-Idade
15.
Cytokine ; 110: 237-242, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29396046

RESUMO

Circulating cytokines, and particularly the interleukin (IL)-family are known to play an important role in inflammation. These molecules circulate in the blood and therefore have a direct effect on the plasma molecules and the formed elements like the erythrocytes and platelets. Aberrant coagulation (hypercoagulation or blood clots that form too easily) and clot lyses (hypofibrinolysis, where clots do not dissolve properly, with an abnormally low rate of clot lysis time), are usually the hallmarks of many inflammatory conditions. However, the mechanism by which cross-linking augments clot stiffness remains undetermined. IL-1ß; IL-6 and IL-8 has been found to be involved in most chronic and acute inflammatory diseases. In the present study, we investigate clot structure of healthy blood, with the addition of these 3 interleukins, to determine the individual effects at concentrations that mimic low-grade, chronic inflammation. Previous studies showed that clot rheological behavior is regulated by at least the following three factors, fibrinogen concentration, fibrin network architecture and FXIIIa-induced ligation. We investigated clot formation and lysis using thromboelastography (TEG), before and after exposure, and created clots by adding thrombin to whole blood. This allowed us to look at extensive fibrin fiber formation and their interactions with particularly the erythrocytes, using scanning electron microscopy (SEM). Our results showed that IL-1ß; IL-6 and IL-8 causes hypercoagulation and results in a disheveled fibrin clot, with trapped RBCs. IL-8 showed eryptosis (a type of apoptosis in erythrocytes). Our lysis results showed that both clot lysis time and maximum rate of lysis are decreased, with the addition of the interleukins. This is a novel finding and the observations reported in this paper, therefore points to the importance of looking at the effects of individual circulating inflammagens, to better understand the role that each play in the expression of disease. These methods can be used for an individualized patient-orientated approach in healthcare to track blood viscosity in conditions with acute and chronic inflammation.


Assuntos
Coagulação Sanguínea/fisiologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Testes de Coagulação Sanguínea/métodos , Plaquetas/metabolismo , Eritrócitos/metabolismo , Fibrina/metabolismo , Tempo de Lise do Coágulo de Fibrina/métodos , Fibrinogênio/metabolismo , Humanos , Inflamação/metabolismo , Trombina/metabolismo
16.
Sci Rep ; 8(1): 1812, 2018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29379088

RESUMO

Tissue necrosis factor-α (TNF-α) and complement component 3 (C3) are two well-known pro-inflammatory molecules. When TNF-α is upregulated, it contributes to changes in coagulation and causes C3 induction. They both interact with receptors on platelets and erythrocytes (RBCs). Here, we look at the individual effects of C3 and TNF-α, by adding low levels of the molecules to whole blood and platelet poor plasma. We used thromboelastography, wide-field microscopy and scanning electron microscopy to study blood clot formation, as well as structural changes to RBCs and platelets. Clot formation was significantly different from the naïve sample for both the molecules. Furthermore, TNF-α exposure to whole blood resulted in platelet clumping and activation and we noted spontaneous plasma protein dense matted deposits. C3 exposure did not cause platelet aggregation, and only slight pseudopodia formation was noted. Therefore, although C3 presence has an important function to cause TNF-α release, it does not necessarily by itself cause platelet activation or RBC damage at these low concentrations. We conclude by suggesting that our laboratory results can be translated into clinical practice by incorporating C3 and TNF-α measurements into broad spectrum analysis assays, like multiplex technology, as a step closer to a patient-orientated, precision medicine approach.


Assuntos
Coagulação Sanguínea/fisiologia , Plaquetas/metabolismo , Complemento C3/metabolismo , Inflamação/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Testes de Coagulação Sanguínea/métodos , Plaquetas/fisiologia , Ativação do Complemento/fisiologia , Eritrócitos/metabolismo , Eritrócitos/fisiologia , Feminino , Humanos , Masculino , Ativação Plaquetária/fisiologia , Agregação Plaquetária/fisiologia , Tromboelastografia/métodos , Adulto Jovem
17.
Br J Haematol ; 180(1): 110-117, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29143311

RESUMO

Inflammation, with its associated inflammatory molecules, is integral to most chronic diseases, including the various cardiovascular diseases. Interleukin 12 (IL12) is one of the inflammatory cytokines that is upregulated during inflammation; however, we know very little about its exact effect on red blood cells (RBCs), platelets and fibrin(ogen). IL12 is an important pleiotropic cytokine in early inflammatory responses and has potent immunomodulatory, antitumour and anti-infection activity. Here we investigate how low levels of circulating IL12, comparable to levels found during chronic inflammation, affect coagulation parameters, platelets and RBCs. We used thromboelastography, scanning electron microscopy, refractometery and wide-field microscopy. Our results show that IL12 caused hypercoagulation, platelet activation and spreading, as well as RBC agglutination. This phenomenon has far-reaching implications for treatment of the plethora of conditions where IL12 is upregulated, since it suggests aberrant haemorheology as agglutination affects blood flow. This information might be used in future to target the lowering of IL12 in inflammatory conditions, as well as address RBC agglutination.


Assuntos
Plaquetas/efeitos dos fármacos , Coagulantes/farmacologia , Eritrócitos/efeitos dos fármacos , Fibrinogênio/metabolismo , Interleucina-12/sangue , Interleucina-12/farmacologia , Adolescente , Adulto , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/ultraestrutura , Técnicas de Imagem por Elasticidade/métodos , Eritrócitos/ultraestrutura , Feminino , Hemorreologia , Humanos , Inflamação/sangue , Inflamação/etiologia , Inflamação/metabolismo , Masculino , Microscopia/métodos , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Refratometria , Adulto Jovem
18.
Cell Physiol Biochem ; 43(3): 1288-1300, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28992628

RESUMO

BACKGROUND/AIMS: Heavy metal pollution is increasing in the environment, contaminating water, food and air supplies. This can be linked to many anthropogenic activities. Heavy metals are absorbed through the skin, inhalation and/or orally. Irrespective of the manner of heavy metal entry in the body, the blood circulatory system is potentially the first to be affected following exposure and adverse effects on blood coagulation can lead to associated thrombotic disease. Although the plasma levels and the effects of cadmium (Cd) and chromium (Cr) on erythrocytes and lymphocytes have been described, the environmental exposure to heavy metals are not limited to a single metal and often involves metal mixtures, with each metal having different rates of absorption, different cellular, tissue, and organ targets. Therefore the aim of this study is to investigate the effects of the heavy metals Cd and Cr alone and whether Cr synergistically increases the effect of Cd on physiological important processes such as blood coagulation. METHODS: Human blood was exposed to the heavy metals ex vivo, and thereafter morphological analysis was performed with scanning electron- and confocal laser scanning microscopy (CLSM) in conjunction with thromboelastography®. RESULTS: The erythrocytes, platelets and fibrin networks presented with ultrastructural changes, including varied erythrocytes morphologies, activated platelets and significantly thicker fibrin fibres in the metal-exposed groups. CLSM analysis revealed the presence of phosphatidylserine on the outer surface of the membranes of the spherocytic erythrocytes exposed to Cd and Cr alone and in combination. The viscoelastic analysis revealed only a trend that indicates that clots that will form after heavy metal exposure, will likely be fragile and unstable especially for Cd and Cr in combination. CONCLUSION: This study identified the blood as an important target system of Cd and Cr toxicity.


Assuntos
Células Sanguíneas/efeitos dos fármacos , Cádmio/toxicidade , Cromo/toxicidade , Plasma/efeitos dos fármacos , Células Sanguíneas/fisiologia , Células Sanguíneas/ultraestrutura , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Plaquetas/ultraestrutura , Elasticidade/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Eritrócitos/ultraestrutura , Fibrina/efeitos dos fármacos , Fibrina/fisiologia , Fibrina/ultraestrutura , Humanos , Microscopia Confocal , Plasma/fisiologia , Tromboelastografia , Viscosidade/efeitos dos fármacos
19.
Thromb Res ; 154: 59-63, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28414934

RESUMO

BACKGROUND: Clotting parameters are informative of overall haematological healthiness of an individual. Particularly, clotting parameters can be used as a measure of the degree of pathology of the coagulation system. Thromboelastography (TEG) is a well-known technique that is an important point-of-care method, as well as research method. Scanning electron microscopy (SEM) is a novel research method, but with possible clinical application. However, there are no clear standardized guidelines for TEG and SEM result interpretation. MATERIALS AND METHODS: We have an extensive database of results from TEG of hypercoagulable, hypocoagulable and healthy whole blood (WB) and platelet poor plasma (PPP). These results were generated using citrated PPP or WB, followed by the addition of CaCl2, to initiate clot formation. We also have an extensive and comprehensive database of thousands of clot micrographs, prepared for SEM. We reanalysed all our data to compile a user-friendly guideline for TEG and SEM. We also discuss the effects of different storage times on both WB and PPP. RESULTS: We provide a quick and informative guide that discusses each TEG parameter, in both WB and PPP. Increases or decreases in the various parameters are indicative of either hyper- or hypocoagulability. We also show how hypo- and hypercoagulable clots look like, compared with healthy clots, using SEM analysis of clots created by adding thrombin to PPP. CONCLUSION: For optimal and speedy interpretation of a patient's coagulation status, it is essential for the clinician to make an informed and precise decision regarding clotting propensity. We believe this guideline will add to the standardization of TEG parameters, and ultimately contribute to the treatment of patients. These guidelines will also allow researchers to standardize their data interpretations and ultimately allow for the use of a global and inclusive database that might be included in precision medicine approaches.


Assuntos
Coagulação Sanguínea , Microscopia Eletrônica de Varredura/métodos , Tromboelastografia/métodos , Testes de Coagulação Sanguínea/métodos , Feminino , Humanos , Masculino , Trombofilia/sangue , Trombofilia/diagnóstico
20.
Inflamm Res ; 66(5): 365-368, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28246677

RESUMO

INTRODUCTION: Type 2 diabetes mellitus is a pandemic associated with disturbance in haemostasis that could contribute to the development of diabetic vascular disease and accelerated atherosclerosis. In this population, hypercoagulation is prevalent, as well as pathological changes to erythrocytes. This is mainly due to upregulated circulating inflammatory markers. MATERIALS AND METHODS: Here we looked at tissue factor (TF) levels using ELISA, in a sample of diabetics, with and without cardiovascular complications. Diabetic subjects were recruited from the diabetic clinic at Steve Biko Academic Hospital, Pretoria, South Africa. 20 diabetics with cardiovascular disease and 22 without were enrolled to participate. RESULTS AND CONCLUSION: TF levels were significantly elevated in both diabetic groups when compared to the controls. We suggest that pathologic plasma TF activity, as marker of increased propensity of clot pathology, should be investigated. Agents that might lower TF levels might also possibly lower thrombotic complications.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/sangue , Tromboplastina/análise , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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