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1.
J Am Heart Assoc ; : e034079, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39056328

ABSTRACT

BACKGROUND: Although related, the precise mechanisms linking obstructive sleep apnea (OSA) and cardiovascular disease (CVD) are unclear. Platelets are mediators of CVD risk and thrombosis and prior studies suggested associations of OSA and platelet activity. The aim of this study is to assess the link between OSA, platelet activity, and CVD-related risk factors. METHODS AND RESULTS: We studied the association of OSA-measures and platelet aggregation in participants dually enrolled in the SHHS (Sleep Heart and Health Study) and FHS (Framingham Heart Study). We applied linear regression models with adjustment for demographic and clinical covariates and explored interactions with OSA and CVD-related factors, including age, sex, body mass index, hypertension, OSA diagnosis (apnea-hypopnea index 4%≥5), and aspirin use. Our final sample was of 482 participants (60 years [14.00], 50.4% female). No associations were observed between apnea-hypopnea index 4% and platelet aggregation in the main sample. Stratified analysis revealed an association in aspirin users (n=65) for our primary exposure (apnea-hypopnea index 4%, ß=0.523; P<0.001; n=65), and secondary exposures: hypoxic burden (ß=0.358; P<0.001), minimum saturation (ß=-0.519; P=0.026), and oxygen desaturation index 3% (ß=74.672; P=0.002). No associations were detected in nonaspirin users (n=417). CONCLUSIONS: No associations were detected between OSA and platelet aggregation in a community sample. Our finding that OSA associates with increased platelet aggregation in the aspirin group, most of whom use it for primary prevention of CVD, suggests that platelet aggregation may mediate the adverse impact of OSA on vascular health in individuals with existing CVD risk, supporting further investigation.

2.
Article in English | MEDLINE | ID: mdl-39012329

ABSTRACT

Fibromuscular dysplasia (FMD) is a disease of the musculature of arterial walls leading to stenoses, aneurysms, and dissections. The purpose of this report was to summarize the evidence for (1) one-time routine imaging from brain-to-pelvis and (2) lifelong antiplatelet therapy, for example, aspirin, for patients diagnosed with FMD as suggested by an international consensus report from 2019. PubMed was systematically searched, and the evidence providing a basis for the current consensus points, as well as articles published since, were reviewed. In four registries evaluating patients with FMD, the prevalence of multivessel involvement, aneurysms, and dissections was reported to be 43.5%-66.3%, 21.6%-30.6%, and 5.6%-28.1%, respectively. Any antiplatelet drug was used in 72.9% of patients, and aspirin was prescribed in up to 70.2% of patients. Based on the high prevalence of vascular manifestations, their associated morbidity, and the potential for endovascular or surgical intervention, the suggestion of one-time brain-to-pelvis screening with computed tomography angiography or magnetic resonance angiography is well supported. Contrarily, the evidence to support the consensus statement of lifelong antiplatelet therapy to all patients in the absence of contraindications is more uncertain since a beneficial effect has not been demonstrated specifically in patients with fibromuscular dysplasia. Therefore, until the efficacy and safety of primary thromboprophylaxis have been demonstrated in this patient group specifically, it may be equally appropriate to only use antiplatelet agents in patients with a clear indication after individual evaluation according to risk factors for thrombotic and thromboembolic complications.

3.
Biomed Res Int ; 2024: 2860547, 2024.
Article in English | MEDLINE | ID: mdl-39035772

ABSTRACT

Background: In February 2021, a few cases of unusual, severe thrombotic events associated with thrombocytopenia reported after vaccination with ChAdOx1 nCoV-19 (Vaxzevria) or with Johnson & Johnson's Janssen vaccine raise concern about safety. The vaccine-induced thrombotic thrombocytopenia (VITT) has been related to the presence of platelet-activating antibodies directed against platelet Factor 4. Objectives: We investigated VITT subject genetic background by a high-throughput whole exome sequencing (WES) approach in order to investigate VITT genetic predisposition. Methods: Six consecutive patients (females of Caucasian origin with a mean age of 64 years) were referred to the Atherothrombotic Diseases Center (Department of Experimental and Clinical Medicine, Azienda Ospedaliero-Universitaria Careggi, Florence) with a diagnosis of definite VITT underwent WES analysis. WES analysis was performed on the Illumina NextSeq500 platform. Results:WES analysis revealed a total of 140,563 genetic variants. Due to VITT's rare occurrence, we focused attention on rare variants. The global analysis of all high-quality rare variants did not reveal a significant enrichment of mutated genes in biological/functional pathways common to patients analyzed. Afterwards, we focused on rare variants in genes associated with blood coagulation and fibrinolysis, platelet activation and aggregation, integrin-mediated signaling pathway, and inflammation with particular attention to those involved in vascular damage, as well as autoimmune thrombocytopenia. According to ACMG criteria, 47/194 (24.2%) rare variants were classified as uncertain significance variants (VUS), whereas the remaining were likely benign/benign. Conclusion: WES analysis identifies rare variants possibly favoring the prothrombotic state triggered by the exposure to the vaccine. Functional studies and/or extensions to a larger number of patients might allow a more comprehensive definition of these molecular pathways.


Subject(s)
Exome Sequencing , Humans , Middle Aged , Female , Aged , Thrombocytopenia/genetics , Thrombocytopenia/chemically induced , ChAdOx1 nCoV-19/adverse effects , Thrombosis/genetics , Genetic Predisposition to Disease , Platelet Factor 4/genetics , Male , Vaccination/adverse effects
4.
Platelets ; 35(1): 2358241, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38832819

ABSTRACT

Acquired disorders of platelet function are an underdiagnosed cause of bleeding tendency. A 14-year-old girl developed moderate mucocutaneous bleeding two weeks after a Mycoplasma pneumoniae infection successfully treated with clarithromycin. The patient was referred to us 7 months later for laboratory investigation of the persisting bleeding diathesis. The patient's personal and family histories were negative for bleeding disorders. Complete blood count, von Willebrand Factor levels and coagulation tests were normal; platelet aggregation, ATP secretion, δ-granules content and serum thromboxane B2 levels were defective. At follow-up visits, laboratory parameters and the bleeding diathesis progressively normalized within 2 years. The patient's condition is compatible with a diagnosis of acquired Storage Pool Deficiency (SPD), associated with defective thromboxane A2 production. To our knowledge, this is the first case of acquired, transient SPD with spontaneous remission. The pathogenic role of Mycoplasma pneumoniae infection or clarithromycin is possible, albeit uncertain.


Subject(s)
Platelet Storage Pool Deficiency , Thromboxane A2 , Humans , Female , Adolescent , Platelet Storage Pool Deficiency/complications , Thromboxane A2/metabolism , Blood Platelets/metabolism , Hemorrhagic Disorders
5.
Curr Vasc Pharmacol ; 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38847250

ABSTRACT

BACKGROUND: Low-dose prasugrel (5 mg) has been proposed for patients with Acute Coronary Syndrome (ACS) and advanced age or low body weight. However, the routine use of dose-adjusted prasugrel in this high-risk subset of patients is still debated. AIM: This study aimed to assess the prevalence and predictors of HRPR among elderly patients treated with low-dose (5 mg) prasugrel to evaluate the routine use of dose-adjusted prasugrel in this high-risk subset of patients. METHODS: We included 59 elderly patients (≥75 years) treated with Dual Antiplatelet Therapy (DAPT: acetylsalicylic acid (ASA) 100-160 mg + prasugrel 5 mg) after Percutaneous Coronary Interventions (PCI) and undergoing platelet function assessment (by whole blood impedance aggregometry) 30-90 days post-discharge. RESULTS: At a median follow-up of 43 days (interquartile range-IQR: 32-54), high-on treatment residual platelet reactivity (HRPR) occurred in 25 patients (42.4%), who displayed a greater body mass index (BMI) (p=0.02), lower levels of vitamin D (p=0.05) and were more frequently treated with nitrates (p=0.03). After multivariate analysis, BMI was the only independent predictor of prasugrel HRPR, and a BMI >26 was the best cut-off for predicting HRPR (adjusted Odds Ratio - OR=8.6, 95%CI: 2.2-33.9, p=0.002). CONCLUSION: Among elderly patients receiving DAPT after PCI, HRPR is common with low-dose prasugrel. A greater BMI, especially for values ≥26, is the only independent predictor of HRPR with prasugrel 5 mg.

6.
Stroke ; 55(7): 1739-1747, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38860396

ABSTRACT

BACKGROUND: The atherosclerotic sources of embolism are a significant contributor to embolic stroke of undetermined source (ESUS). However, there is limited evidence for the efficacy of intensive dual antiplatelet therapy for ESUS. We conducted an investigation to determine whether gene-directed dual antiplatelet therapy could reduce the risk of recurrent stroke in patients with ESUS. METHODS: CHANCE-2 (Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events-II) was an investigator-initiated, multicenter, randomized, double-blind, placebo-controlled trial that objectively compared ticagrelor plus aspirin and clopidogrel plus aspirin in patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles in China. All study participants were classified into ESUS and non-ESUS groups for the prespecified exploratory analysis. Cox proportional hazards models were used to assess the interaction of the state of ESUS with the effects of dual antiplatelet therapy with ticagrelor-aspirin versus clopidogrel-aspirin, adjusting for sociodemographic and clinical factors. RESULTS: The subgroup analysis comprised 5796 participants (90.4% of the total 6412 participants) in the CHANCE-2 trial, with a median age of 64.9 years (range, 57.0-71.4 years), of whom 1964 (33.9%) were female. These participants underwent diffusion-weighted imaging as part of the study protocol. After systematic evaluation, 15.2% of patients (881/5796) were deemed to have ESUS. The incidence of stroke recurrence in patients with ESUS was found to be 5.6% in the ticagrelor-aspirin group and 9.2% in the clopidogrel-aspirin group (hazard ratio, 0.57 [95% CI, 0.33-0.99]; P=0.04). In patients without ESUS, the respective incidence rates were 5.6% and 7.5% (hazard ratio, 0.72 [95% CI, 0.58-0.90]; P<0.01). The P value was 0.56 for the treatment × ESUS status interaction effect. CONCLUSIONS: In this prespecified exploratory analysis, ticagrelor with aspirin was superior to clopidogrel with aspirin for preventing stroke at 90 days in patients with acute ischemic stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles and were classified as ESUS. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04078737.


Subject(s)
Aspirin , Clopidogrel , Dual Anti-Platelet Therapy , Embolic Stroke , Platelet Aggregation Inhibitors , Ticagrelor , Humans , Middle Aged , Female , Male , Platelet Aggregation Inhibitors/therapeutic use , Aged , Clopidogrel/therapeutic use , Aspirin/therapeutic use , Ticagrelor/therapeutic use , Double-Blind Method , Dual Anti-Platelet Therapy/methods , Embolic Stroke/drug therapy , Embolic Stroke/etiology , Cytochrome P-450 CYP2C19/genetics , Stroke/drug therapy
7.
J Maxillofac Oral Surg ; 23(3): 727-733, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38911395

ABSTRACT

Background/Purpose: The present study aimed to investigate plastic tubes without additives as alternatives to glass and silica-coated plastic tubes, in the production of PRF membranes. Materials and Methods: Nine blood samples were collected from eight volunteers (n = 8) separated into three groups, according to tube material: glass, silica-coated plastic, and plastic without additives. In each group, the samples were centrifuged using different relative centrifugation forces: L-PRF (700 g/12 min), A-PRF (200 g/14 min), and A-PRF + (200 g/8 min). The generated membranes were evaluated by histomorphometry, considering the fibrin network, platelet aggregates, and cellular morphology, by light microscopy. The ultrastructural cellular morphology integrity was evaluated by transmission electron microscopy. Results: The L-PRF (p < 0.019) and A-PRF (p < 0.001) membranes showed a significantly lower fibrin network density in plastic tubes without additives compared to glass and silica-coated plastic tubes. Plastic tubes without additives revealed a significantly higher platelet percentage, regardless of the protocol (p < 0.005). In all groups, TEM analysis showed preserved normal morphological ultrastructure, maintaining the integrity of cellular components. Conclusion: Plastic tubes without additives offer a viable alternative for producing PRF membranes. They exhibited a higher platelet density and demonstrated fibrin network and cellular morphology similar to those of glass and silica-coated plastic tubes, irrespective of the centrifugation protocol.

8.
Biomolecules ; 14(6)2024 May 23.
Article in English | MEDLINE | ID: mdl-38927016

ABSTRACT

Platelets play essential roles in the formation of blood clots by clumping with coagulation factors at the site of vascular injury to stop bleeding; therefore, a reduction in the platelet number or disorder in their function causes bleeding risk. In our research, we developed a method to assess platelet aggregation using an optical approach within a microfluidic chip's channel by evaluating the size of laser speckles. These speckles, associated with slowed blood flow in the microfluidic channel, had a baseline size of 28.54 ± 0.72 µm in whole blood. Removing platelets from the sample led to a notable decrease in speckle size to 27.04 ± 1.23 µm. Moreover, the addition of an ADP-containing agonist, which activates platelets, resulted in an increased speckle size of 32.89 ± 1.69 µm. This finding may provide a simple optical method via microfluidics that could be utilized to assess platelet functionality in diagnosing bleeding disorders and potentially in monitoring therapies that target platelets.


Subject(s)
Blood Platelets , Platelet Aggregation , Blood Platelets/drug effects , Humans , Platelet Aggregation/drug effects , Platelet Function Tests/methods , Platelet Function Tests/instrumentation , Lab-On-A-Chip Devices , Microfluidic Analytical Techniques/instrumentation , Microfluidic Analytical Techniques/methods , Microfluidics/methods , Adenosine Diphosphate/pharmacology
9.
Biomolecules ; 14(6)2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38927117

ABSTRACT

The crucial role of platelets in hemostasis and their broad implications under various physiological conditions underscore the importance of accurate platelet-function testing. Platelets are key to clotting blood and healing wounds. Therefore, accurate diagnosis and management of platelet disorders are vital for patient care. This review outlines the significant advancements in platelet-function testing technologies, focusing on their working principles and the shift from traditional diagnostic methods to more innovative approaches. These improvements have deepened our understanding of platelet-related disorders and ushered in personalized treatment options. Despite challenges such as interpretation of complex data and the costs of new technologies, the potential for artificial-intelligence integration and the creation of wearable monitoring devices offers exciting future possibilities. This review underscores how these technological advances have enhanced the landscape of precision medicine and provided better diagnostic and treatment options for platelet-function disorders.


Subject(s)
Blood Platelet Disorders , Blood Platelets , Platelet Function Tests , Humans , Blood Platelets/metabolism , Blood Platelet Disorders/diagnosis , Blood Platelet Disorders/therapy , Blood Platelet Disorders/blood , Platelet Function Tests/methods , Precision Medicine/methods , Hemostasis
10.
Korean J Gastroenterol ; 83(6): 217-232, 2024 Jun 25.
Article in Korean | MEDLINE | ID: mdl-38918035

ABSTRACT

Antithrombotic agents, including antiplatelet agent and anticoagulants are widely used in Korea due to increasing incidence of cardio-cerebrovascular disease and aging population. The management of patients using antithrombotic agents during endoscopic procedures is an important clinical challenge. Clinical practice guideline regarding this issue which was developed by the Korean Society of Gastrointestinal Endoscopy was published in 2020. However, since then, new evidence has emerged for the use of dual antiplatelet therapy and direct anticoagulant management, and revised guidelines were issued in the US and Europe. Accordingly, the previous guidelines were revised, cardiologists also participated in the development group, and the recommendations went through a consensus process among international experts. This guideline presents 14 recommendations made according to the Grading of Recommendations, Assessment, Development, and Evaluation methodology, and was reviewed by multidisciplinary experts. This guideline provides useful information that can assist endoscopists in the management of patients on antithrombotic agents who require diagnostic and elective therapeutic endoscopy. It will be revised as necessary to cover changes in technology, evidence, or other aspects of clinical practice.


Subject(s)
Anticoagulants , Endoscopy, Gastrointestinal , Fibrinolytic Agents , Platelet Aggregation Inhibitors , Humans , Fibrinolytic Agents/therapeutic use , Platelet Aggregation Inhibitors/therapeutic use , Anticoagulants/therapeutic use , Consensus , Gastrointestinal Hemorrhage
11.
Pharmaceuticals (Basel) ; 17(6)2024 May 30.
Article in English | MEDLINE | ID: mdl-38931377

ABSTRACT

Selective COX-1 inhibitors are preferential therapeutic targets for platelet aggregation and clotting responses. In this study, we examined the selective COX-1-inhibitory activities of four newly synthesized compounds, 10-13, along with their abilities to inhibit platelet aggregation against ADP and collagen. The target compounds 10-13 were synthesized using the conventional method, sonication, and microwave-assisted methods. Microanalytical and spectral data were utilized to elucidate the structures of the new compounds 10-13. Additionally, a spectral NMR experiment [NOESY] was conducted to emphasize the configuration around the double bond of the imine group C=N. The obtained results revealed no observed correlation between any of the neighboring protons, suggesting that the configuration at the C=N double bond is E. Biological results revealed that all the screened compounds 10-13 might serve as selective COX-1 inhibitors. They showed IC50 values ranging from 0.71 µM to 4.82 µM against COX-1 and IC50 values ranging from 9.26 µM to 15.24 µM against COX-2. Their COX-1 selectivity indices ranged between 2.87 and 18.69. These compounds show promise as promising anti-platelet aggregation agents. They effectively prevented platelet aggregation induced by ADP with IC50 values ranging from 0.11 µM to 0.37 µM, surpassing the standard aspirin with an IC50 value of 0.49 µM. Additionally, they inhibited the platelet aggregation induced by collagen with IC50 values ranging from 0.12 µM to 1.03 µM, demonstrating superior efficacy compared to aspirin, which has an IC50 value of 0.51 µM. In silico molecular modeling was performed for all the target compounds within the active sites of COX-1 and COX-2 to rationalize their selective inhibitory activities towards COX-1. It was found that the binding interactions of the designed compounds within the COX-1 active site had remained unaffected by the presence of celecoxib. Molecular modeling and DFT calculations using the B3LYP/6-31+G (d,p) level were performed to study the stability of E-forms with respect to Z-forms for the investigated compounds. A strong correlation was observed between the experimental observations and the quantum chemical descriptors.

12.
Ann Cardiol Angeiol (Paris) ; 73(3): 101761, 2024 Jun.
Article in French | MEDLINE | ID: mdl-38754180

ABSTRACT

After a first episode of unprovoked vein thrombosis, the risk of recurrence persists for many years. Long term of anticoagulant therapy prevents the recurrence of vein thrombosis but is associated with a major risk of bleeding. As platelets play a role in the initiation and propagation of venous thromboembolism as well, antiplatelet agents, may play a role in the treatment and prevention of this disease. This review summarizes available evidence on effect of aspirin in the prevention of recurrent deep vein thrombosis.


Subject(s)
Aspirin , Platelet Aggregation Inhibitors , Secondary Prevention , Venous Thromboembolism , Humans , Aspirin/therapeutic use , Venous Thromboembolism/prevention & control , Platelet Aggregation Inhibitors/therapeutic use , Recurrence
13.
Indian J Hematol Blood Transfus ; 40(2): 281-288, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38708151

ABSTRACT

To determine whether there is higher degree of platelet and/ or coagulation activation in sickle cell anaemia (SS) patients in complications and with clinical risk factors. A cross sectional study was conducted at a tertiary health care centre in central India with study groups: sickle cell disease (SCD): sickle cell anaemia (SS) and sickle cell trait (AS) consisting of 100 subjects each and controls (AA) with 40 subjects. Platelet aggregation (PA) with ADP, collagen and epinephrine, PT and aPTT were performed in all subjects and PA with ristocetin in ten candidates of each group. ANOVA and student's unpaired t test were used to compare PA and coagulation profile of the three groups with respect to age groups, gender, present diagnosis, history of complications, frequency of hospital admissions (high ≥ 3/year) and frequency of blood transfusion (high > 2/year). The max PA% with ADP was significantly less in SS patients in steady state, which was even lesser in those having symptoms, complications in past/ present, high-frequency hospital admission and > 2 blood transfusions per year subgroups, as compared to all other groups and subgroups, but not consistently with collagen and epinephrine. The max PA % with ristocetin was least in SS with complications. No statistically significant difference in PT and aPTT values among the various clinical risk subgroups and groups was found. SCD patients can be monitored by using PA with ADP for their timely and better management. PA with ADP, PT and aPTT should be added to the workup of these patients for improved prognostication.

14.
Biomed Khim ; 70(2): 99-108, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38711409

ABSTRACT

Platelet functional activity was assessed in healthy volunteers (HV, n=92), patients with stable angina pectoris (SA, n=42) and acute coronary syndrome (ACS, n=73), treated with acetylsalicylic acid (ASA) + clopidogrel and ASA + ticagrelor, respectively. In all HV and patients we have compared parameters of platelet aggregation (maximum light transmission and velocity, Tmax and Vmax) and parameters, characterizing exposure of platelet activation markers, evaluated by flow cytometry. HV platelets were activated by 10 µM, 1 µM TRAP, and 20 µM, 5 µM, 2.5 µM ADP; patient platelets were activated by 10 µM TRAP and by 20 µM and 5 µM ADP. Strong and significant correlations between the aggregation and flow cytometry parameters (the r correlation coefficient from 0.4 up to >0.6) most frequently were registered in HV platelet during activation by 1 µM TRAP and in SA patients during platelet activation by 20 µM and 5 µM ADP. However, in many other cases these correlations were rather weak (r < 0.3) and sometimes statistically insignificant. In HV the differences in PAC-1 binding parameters between platelets activated by 10 µM TRAP (the strongest agonist) and all ADP concentrations were negligible (≤ 10%), while CD62P binding (at all ADP concentrations) and LTA parameters for (5 µM and 2.5 µM ADP) were significantly lower (by 40-60%). Antiplatelet therapy in patients decreased all parameters as compared to HV, but to varying extents. For 10 µM TRAP the MFI index for PAC-1 binding (40-50% decrease) and for both ADP concentrations the Tmax values (60-85% decrease) appeared to be the most sensitive in comparison with the other parameters that decreased to a lesser extent. The data obtained indicate a possibility of inconsistency between different LTA and flow cytometry parameters in assessing platelet activity and efficacy of antiplatelet drugs.


Subject(s)
Acute Coronary Syndrome , Aspirin , Blood Platelets , Clopidogrel , Flow Cytometry , Platelet Aggregation Inhibitors , Platelet Aggregation , Humans , Platelet Aggregation Inhibitors/pharmacology , Platelet Aggregation/drug effects , Male , Aspirin/pharmacology , Aspirin/therapeutic use , Female , Blood Platelets/drug effects , Blood Platelets/metabolism , Middle Aged , Clopidogrel/pharmacology , Aged , Acute Coronary Syndrome/drug therapy , Acute Coronary Syndrome/blood , Adult , Ticagrelor/pharmacology , Ticagrelor/therapeutic use , Platelet Function Tests/methods , Platelet Activation/drug effects , Angina, Stable/drug therapy , Angina, Stable/blood , Adenosine Diphosphate/pharmacology
15.
Cureus ; 16(4): e57994, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38738084

ABSTRACT

Thrombotic thrombocytopenic purpura (TTP) is a rare, life-threatening disorder typically presenting with a classic pentad of symptoms: thrombocytopenia, microangiopathic hemolytic anemia, neurological abnormalities, renal dysfunction, and fever. This report explores an unusual presentation of TTP in a 47-year-old female with a medical history of hypertension, hyperlipidemia, and chronic TTP, who exhibited only petechial rashes, generalized weakness, and headache. Notably, the petechial rash, a less common manifestation of TTP, became a pivotal clue for the diagnosis, underscoring the necessity for vigilance even when classic symptoms are absent. This case reinforces the imperative of a high suspicion index for TTP, especially in patients with thrombocytopenia and hemolytic anemia, irrespective of other traditional signs. Plasmapheresis remains the treatment cornerstone, removing autoantibodies and replenishing ADAMTS13, as evidenced by the patient's initial response. The administration of rituximab, targeting B cells to mitigate autoantibody production against ADAMTS13, featured prominently in her management, aligning with its recognized role in refractory or relapsing TTP cases. Despite an encouraging response to rituximab, a subsequent decline in platelet count indicated the unpredictable nature of TTP and the necessity for multi-pronged therapeutic strategies. The patient's medical background and persistently low ADAMTS13 levels hinted at a chronic relapsing trajectory associated with increased morbidity and mortality. This necessitates ongoing vigilance and treatment flexibility. Highlighting this atypical TTP presentation, the report calls for immediate, robust intervention, serving as a critical reminder of the heterogeneity of TTP manifestations and the complexities in its management, thereby contributing to broader clinical awareness and improved patient prognoses.

16.
Int J Mol Sci ; 25(9)2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38732019

ABSTRACT

Thrombosis is the pathological clot formation under abnormal hemodynamic conditions, which can result in vascular obstruction, causing ischemic strokes and myocardial infarction. Thrombus growth under moderate to low shear (<1000 s-1) relies on platelet activation and coagulation. Thrombosis at elevated high shear rates (>10,000 s-1) is predominantly driven by unactivated platelet binding and aggregating mediated by von Willebrand factor (VWF), while platelet activation and coagulation are secondary in supporting and reinforcing the thrombus. Given the molecular and cellular level information it can access, multiscale computational modeling informed by biology can provide new pathophysiological mechanisms that are otherwise not accessible experimentally, holding promise for novel first-principle-based therapeutics. In this review, we summarize the key aspects of platelet biorheology and mechanobiology, focusing on the molecular and cellular scale events and how they build up to thrombosis through platelet adhesion and aggregation in the presence or absence of platelet activation. In particular, we highlight recent advancements in multiscale modeling of platelet biorheology and mechanobiology and how they can lead to the better prediction and quantification of thrombus formation, exemplifying the exciting paradigm of digital medicine.


Subject(s)
Blood Platelets , Hemostasis , Thrombosis , Humans , Thrombosis/metabolism , Blood Platelets/metabolism , Hemostasis/physiology , Platelet Activation , Animals , Platelet Adhesiveness , Platelet Aggregation
17.
J Ethnopharmacol ; 332: 118298, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-38714238

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Green tea (Camellia sinensis) is a popular beverage consumed all over the world due to its health benefits. Many of these beneficial effects of green tea are attributed to polyphenols, particularly catechins. AIM OF THE STUDY: The present study focuses on underlying anti-platelet aggregation, anti-thrombotic, and anti-lipidemic molecular mechanisms of green tea in South Indian smokers. MATERIALS AND METHODS: We selected 120 South Indian male volunteers for this study to collect the blood and categorised them into four groups; control group individuals (Controls), smokers, healthy control individuals consuming green tea, and smokers consuming green tea. Smokers group subjects have been smoking an average 16-18 cigarettes per day for the last 7 years or more. The subjects (green tea consumed groups) consumed 100 mL of green tea each time, thrice a day for a one-year period. RESULTS: LC-MS analysis revealed the presence of multiple phytocompounds along with catechins in green tea extract. Increased plasma lipid peroxidation (LPO), protein carbonyls, cholesterol, triglycerides, and LDL-cholesterol with decreased HDL-cholesterol levels were observed in smokers compared to the control group and the consumption of green tea showed beneficial effect. Furthermore, docking studies revealed that natural compounds of green tea had high binding capacity with 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA) when compared to their positive controls, whereas (-) epigallocatechin-3-gallate (EGCG) and (-) epicatechin-gallate (ECG) had high binding capacity with sterol regulatory element-binding transcription factor 1 (SREBP1c). Further, our ex vivo studies showed that green tea extract (GTE) significantly inhibited platelet aggregation and increased thrombolytic activity in a dose dependent manner. CONCLUSION: In conclusion, in smokers, catechins synergistically lowered oxidative stress, platelet aggregation and modified the aberrant lipid profile. Furthermore, molecular docking studies supported green tea catechins' antihyperlipidemic efficacy through strong inhibitory activity on HMG-CoA reductase and SREBP1c. The mitigating effects of green tea on cardiovascular disease risk factors in smokers that have been reported can be attributed majorly to catechins or to their synergistic effects.


Subject(s)
Camellia sinensis , Molecular Docking Simulation , Plant Extracts , Tea , Humans , Male , India , Adult , Camellia sinensis/chemistry , Tea/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Plant Extracts/chemistry , Smoking , Middle Aged , Atherosclerosis/drug therapy , Atherosclerosis/prevention & control , Smokers , Catechin/pharmacology , Catechin/analogs & derivatives , Lipids/blood , Antioxidants/pharmacology , Platelet Aggregation Inhibitors/pharmacology , Platelet Aggregation/drug effects
18.
Life Sci ; 350: 122746, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38810792

ABSTRACT

AIMS: Dysregulated platelet aggregation is a fatal condition in many bacterial- and virus-induced diseases. However, classical antithrombotics cannot completely prevent immunothrombosis, due to the unaddressed mechanisms towards inflammation. Thus, targeting platelet hyperactivation together with inflammation might provide new treatment options in diseases, characterized by immunothrombosis, such as COVID-19 and sepsis. The aim of this study was to investigate the antiaggregatory effect and mode of action of 1.8-cineole, a monoterpene derived from the essential oil of eucalyptus leaves, known for its anti-inflammatory proprieties. MAIN METHODS: Platelet activity was monitored by measuring the expression and release of platelet activation markers, i.e., P-selectin, CD63 and CCL5, as well as platelet aggregation, upon treatment with 1.8-cineole and stimulation with several classical stimuli and bacteria. A kinase activity assay was used to elucidate the mode of action, followed by a detailed analysis of the involvement of the adenylyl-cyclase (AC)-cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) pathway by Western blot and ELISA. KEY FINDINGS: 1.8-cineole prevented the expression and release of platelet activation markers, as well as platelet aggregation, upon induction of aggregation with classical stimuli and immunological agonists. Mechanistically, 1.8- cineole influences the activation of the AC-cAMP-PKA pathway, leading to higher cAMP levels and vasodilator-stimulated phosphoprotein (VASP) phosphorylation. Finally, blocking the adenosine A2A receptor reversed the antithrombotic effect of 1.8-cineole. SIGNIFICANCE: Given the recognized anti-inflammatory attributes of 1.8-cineole, coupled with our findings, 1.8-cineole might emerge as a promising candidate for treating conditions marked by platelet activation and abnormal inflammation.


Subject(s)
Cyclic AMP , Eucalyptol , Platelet Activation , Platelet Aggregation , Receptor, Adenosine A2A , Eucalyptol/pharmacology , Receptor, Adenosine A2A/metabolism , Platelet Activation/drug effects , Platelet Aggregation/drug effects , Humans , Cyclic AMP/metabolism , Blood Platelets/metabolism , Blood Platelets/drug effects , Signal Transduction/drug effects , P-Selectin/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Platelet Aggregation Inhibitors/pharmacology , Anti-Inflammatory Agents/pharmacology , COVID-19/metabolism
19.
Article in English | MEDLINE | ID: mdl-38704867

ABSTRACT

OBJECTIVES: There is a lack of high-quality data informing the optimal antithrombotic drug strategy following bioprosthetic heart valve replacement or valve repair. Disparity in recommendations from international guidelines reflects this. This study aimed to document current patterns of antithrombotic prescribing after heart valve surgery in the UK. METHODS: All UK consultant cardiac surgeons were e-mailed a custom-designed survey. The use of oral anticoagulant (OAC) and/or antiplatelet drugs following bioprosthetic aortic valve replacement or mitral valve replacement, or mitral valve repair (MVrep), for patients in sinus rhythm, without additional indications for antithrombotic medication, was assessed. Additionally, we evaluated anticoagulant choice following MVrep in patients with atrial fibrillation. RESULTS: We identified 260 UK consultant cardiac surgeons from 36 units, of whom 103 (40%) responded, with 33 units (92%) having at least 1 respondent. The greatest consensus was for patients undergoing bioprosthetic aortic valve replacement, in which 76% of surgeons favour initial antiplatelet therapy and 53% prescribe lifelong treatment. Only 8% recommend initial OAC. After bioprosthetic mitral valve replacement, 48% of surgeons use an initial OAC strategy (versus 42% antiplatelet), with 66% subsequently prescribing lifelong antiplatelet therapy. After MVrep, recommendations were lifelong antiplatelet agent alone (34%) or following 3 months OAC (20%), no antithrombotic agent (20%), or 3 months OAC (16%). After MVrep for patients with established atrial fibrillation, surgeons recommend warfarin (38%), a direct oral anticoagulant (37%) or have no preference between the 2 (25%). CONCLUSIONS: There is considerable variation in the use of antithrombotic drugs after heart valve surgery in the UK and a lack of high-quality evidence to guide practice, underscoring the need for randomized studies.

20.
Pharmaceuticals (Basel) ; 17(5)2024 Apr 28.
Article in English | MEDLINE | ID: mdl-38794134

ABSTRACT

Polypharmacy is a global healthcare concern, especially among the elderly, leading to drug interactions and adverse reactions, which are significant causes of death in developed nations. However, the integration of pharmacogenetics can help mitigate these risks. In this study, the data from 483 patients, primarily elderly and polymedicated, were analyzed using Eugenomic®'s personalized prescription software, g-Nomic®. The most prescribed drug classes included antihypertensives, platelet aggregation inhibitors, cholesterol-lowering drugs, and gastroprotective medications. Drug-lifestyle interactions primarily involved inhibitions but also included inductions. Interactions were analyzed considering gender. Significant genetic variants identified in the study encompassed ABCB1, SLCO1B1, CYP2C19, CYP2C9, CYP2D6, CYP3A4, ABCG2, NAT2, SLC22A1, and G6PD. To prevent adverse reactions and enhance medication effectiveness, it is strongly recommended to consider pharmacogenetics testing. This approach shows great promise in optimizing medication regimens and ultimately improving patient outcomes.

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