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Frontiers in Immunology 2023Transcription factors bind promoter or regulatory sequences of a gene to regulate its rate of transcription. However, they are also detected in anucleated platelets. The... (Review)
Review
Transcription factors bind promoter or regulatory sequences of a gene to regulate its rate of transcription. However, they are also detected in anucleated platelets. The transcription factors RUNX1, GATA1, STAT3, NFκB, and PPAR have been widely reported to play key roles in the pathophysiology of platelet hyper-reactivity, thrombosis, and atherosclerosis. These non-transcriptional activities are independent of gene transcription or protein synthesis but their underlying mechanisms of action remain poorly defined. Genetic and acquired defects in these transcription factors are associated with the production of platelet microvesicles that are known to initiate and propagate coagulation and to promote thrombosis. In this review, we summarize recent developments in the study of transcription factors in platelet generation, reactivity, and production of microvesicles, with a focus on non-transcriptional activities of selected transcription factors.
Topics: Humans; Megakaryocytes; Transcription Factors; Blood Platelets; Platelet Count; Thrombosis
PubMed: 36969155
DOI: 10.3389/fimmu.2023.1140501 -
Periodontology 2000 Feb 2024The use of platelet-rich fibrin (PRF) has gained tremendous popularity in recent years owing to its ability to speed wound healing postsurgery. However, to date, many... (Review)
Review
The use of platelet-rich fibrin (PRF) has gained tremendous popularity in recent years owing to its ability to speed wound healing postsurgery. However, to date, many clinicians are unaware of methods designed to optimize the technology. This overview article will discuss the advancements and improvements made over the years aimed at maximizing cell and growth factor concentrations. First, a general understanding explaining the differences between RPM and RCF (g-force) is introduced. Then, the low-speed centrifugation concept, fixed angle versus horizontal centrifugation, and methods to maximize platelet concentrations using optimized protocols will be discussed in detail. Thereafter, the importance of chemically modified PRF tubes without the addition of chemical additives, as well as regulation of temperature to induce/delay clotting, will be thoroughly described. This article is a first of its kind summarizing all recent literature on PRF designed to optimize PRF production for clinical treatment.
Topics: Humans; Platelet-Rich Fibrin; Centrifugation; Wound Healing; Blood Platelets; Intercellular Signaling Peptides and Proteins; Platelet Count; Blood Coagulation
PubMed: 37681522
DOI: 10.1111/prd.12521 -
Ginekologia Polska 2021Thrombocytopenia is one of the two most common hematological problems in pregnant women. It is defined as the platelet (PLT) count below 150 × 103/μL. Gestational...
Thrombocytopenia is one of the two most common hematological problems in pregnant women. It is defined as the platelet (PLT) count below 150 × 103/μL. Gestational incidental thrombocytopenia (GIT) represents about 75% of thrombocytopenia cases in pregnancy and it is believed that GIT is secondary to accelerated platelet destruction and increased plasma volume associated with pregnancy. The pregnancy complications such as preeclampsia and its most severe form - HELLP syndrome account for 20% cases of thrombocytopenia in pregnancy and primary immune thrombocytopenic purpura (ITP) - for 3-4 percent. During ITP, maternal antiplatelet antibodies can pass through the placenta and bind to fetal thrombocytes leading to the development of fetal thrombocytopenia which occurs in about 50% cases. Even if the maternal platelet count stabilizes, the estimated fetal and neonatal risk of thrombocytopenia in ITP is approximately 30%. Other types of thrombocytopenia in pregnant women constitute 1-2% of cases (disseminated intravascular coagulation, autoimmunological diseases, congenital, infection and drug-related, concomitant with blood neoplastic diseases). Although thrombocytopenia in pregnant women usually has a mild course, in case of a significant decrease in PLT count may lead to dangerous bleeding, especially when the platelet count falls below 20 × 103/μL. Since it is important to identify the cause of thrombocytopenia and to determine the risk for both the mother and the child, this paper presents the influence of maternal thrombocytopenia on the pregnancy course as well as its etiology and diagnostics. The treatment principles are discussed.
Topics: Child; Female; Humans; Infant, Newborn; Platelet Count; Pregnancy; Pregnancy Complications, Hematologic; Pregnant Women; Purpura, Thrombocytopenic, Idiopathic; Thrombocytopenia
PubMed: 34541631
DOI: 10.5603/GP.a2021.0147 -
The American Journal of Case Reports Jun 2021BACKGROUND Recently, some case reports have been published on the macrolide antimicrobials azithromycin and clarithromycin as the cause of thrombocytopenia. The publicly...
BACKGROUND Recently, some case reports have been published on the macrolide antimicrobials azithromycin and clarithromycin as the cause of thrombocytopenia. The publicly accessible databases of the European Medicine Agency and the WHO drug monitoring program contain dozens of reports of roxithromycin-associated thrombocytopenia. CASE REPORT We described the case of a 78-year-old woman presenting to our unit with petechial lesions of the palate, 2 hematomas of the tongue, and purpuric macules in the abdomen and in the left lower limb 4 days after a course of roxithromycin. She presented to the Emergency Department with 3 out-of-range blood test results: neutrophils (11 960/mL; range: 1500-7000/mL), platelet count (3000/mL; range: 150 000-400 000/mL), and lactate dehydrogenase (379 IU/L; range: 135-225 IU/L). Thrombocytopenia occurred in the absence of aggregates and observed nucleolated lymphocytes. Lymphoproliferative pathologies and thrombotic microangiopathy were excluded by the hematologist. To rule out neoplastic lesions, an abdominal ultrasound examination was made. Antibody screening was performed for antinuclear antibodies, extractable nuclear antigen, antineutrophil cytoplasmic antibodies (all negative), and for Parvovirus B-19 (IgM negative, IgG positive), as well as HHV-6 and HHV-8 (both negative), to exclude an autoimmune or viral etiology. She recovered after intravenous methylprednisolone 60 mg/day and intravenous-immunoglobulin therapy 400 mg/kg/day. After 9 days, the patient was discharged with resolution of skin and buccal lesions. Her platelet count was 515 000/mL. CONCLUSIONS To the best of our knowledge, this is the first case of roxithromycin-associated acute autoimmune thrombocytopenia reported in the medical literature. We suggest that clinicians should consider this drug to be among the possible causes of drug-induced thrombocytopenia.
Topics: Aged; Female; Humans; Immunoglobulins, Intravenous; Platelet Count; Purpura, Thrombocytopenic, Idiopathic; Roxithromycin; Thrombocytopenia
PubMed: 34188012
DOI: 10.12659/AJCR.932039 -
Platelets Dec 2023Platelets play a critical role in immune response. Coronavirus disease 2019 (COVID-19) patients with a severe course often show pathological coagulation parameters...
Platelets play a critical role in immune response. Coronavirus disease 2019 (COVID-19) patients with a severe course often show pathological coagulation parameters including thrombocytopenia, and at the same time the proportion of immature platelets increases. In this study, the platelet count and the immature platelet fraction (IPF) of hospitalized patients with different oxygenation requirements was investigated daily over a course of 40 days. In addition, the platelet function of COVID-19 patients was analyzed. It was found that the number of platelets in patients with the most severe course (intubation and extracorporeal membrane oxygenation (ECMO)) was significantly lower (111.5 ∙ 10 /mL) than in the other groups (mild (no intubation, no ECMO): 203.5 ∙ 10 /mL, < .0001, moderate (intubation, no ECMO): 208.0 ∙ 10 /mL, < .0001). IPF tended to be elevated (10.9%). Platelet function was reduced. Differentiation by outcome revealed that the deceased patients had a highly significant lower platelet count and higher IPF (97.3 ∙ 10 /mL, < .0001, 12.2%, = .0003).
Topics: Humans; COVID-19; Blood Platelets; Thrombocytopenia; Platelet Count; Blood Coagulation
PubMed: 36883692
DOI: 10.1080/09537104.2023.2184183 -
Endokrynologia Polska 2021
Topics: Adolescent; Anorexia Nervosa; Blood Platelets; Bone Density; Female; Humans; Lymphocyte Count; Lymphocytes; Neutrophils; Platelet Count
PubMed: 34010435
DOI: 10.5603/EP.a2021.0036 -
Frontiers in Immunology 2023Thrombocytopenia, characterized by a decrease in platelet count, is commonly observed in sepsis and COVID-19. In sepsis, thrombocytopenia can result from various... (Review)
Review
Thrombocytopenia, characterized by a decrease in platelet count, is commonly observed in sepsis and COVID-19. In sepsis, thrombocytopenia can result from various mechanisms, including impaired platelet production in the bone marrow, accelerated platelet destruction due to increased inflammation, sequestration of platelets in the spleen, immune-mediated platelet destruction, or dysregulated host responses. Similarly, thrombocytopenia has been reported in COVID-19 patients, but the immune-related mechanisms underlying this association remain unclear. Notably, interventions targeting thrombocytopenia have shown potential for improving outcomes in both sepsis and COVID-19 patients. Understanding these mechanisms is crucial for developing effective treatments.
Topics: Humans; COVID-19; Thrombocytopenia; Blood Platelets; Platelet Count; Sepsis; Anemia
PubMed: 37841241
DOI: 10.3389/fimmu.2023.1213510 -
Frontiers in Immunology 2023
Topics: Humans; Megakaryocytes; Blood Platelets; Platelet Count; Communicable Diseases
PubMed: 37056755
DOI: 10.3389/fimmu.2023.1175200 -
Frontiers in Immunology 2022Some degree of platelet index abnormality has been found clinically in the autoimmune thyroid disease (AITD), but the findings are not uniform. (Meta-Analysis)
Meta-Analysis
BACKGROUND
Some degree of platelet index abnormality has been found clinically in the autoimmune thyroid disease (AITD), but the findings are not uniform.
METHODS
The PubMed, Web of Science, Cochrane Library, and Embase databases were searched for relevant articles published up to August 16th, 2022, with no restrictions on the language of the articles. Reference lists of eligible articles were also searched. A random effect model was used to pool the standardized mean difference (SMD) and 95% confidence interval (95% CI) of platelet count (PLT), mean platelet volume (MPV), and platelet distribution width (PDW) between AITD patients and healthy controls, and subgroup analyses were performed.
RESULTS
A total of 19 articles with 6173 people (3824 AITD patients and 2349 healthy people) were included in the meta-analysis. The results showed that PLT and MPV values were significantly increased in AITD patients when compared with healthy people (SMD: 0.164, 95% CI: 0.044 to 0.285; SMD: 0.256, 95% CI: 0.013 to 0.500), while no significant difference was found in PDW between the AITD group and the control group (SMD: 0.060, 95% CI: -0.164 to 0.284). Subgroup analysis according to disease type and thyroid function revealed that for PLT, this difference was only found in the Hashimoto's thyroiditis (HT) and hypothyroid groups, but not in the Graves' disease (GD) and hyperthyroid groups. For MPV, the results were the opposite of those for PLT: MPV was significantly higher in the GD, hyperthyroid, and euthyroid groups than in the control group, but not in the HT and hypothyroid groups. Sensitivity analysis showed that the stability of the pooled MPV was not good. No publication bias was found.
CONCLUSIONS
PLT and MPV are significantly elevated in patients with AITD, with PLT being more significantly elevated in HT and hypothyroidism, and MPV being more significantly increased in GD and hyperthyroidism. Appropriate clinical attention can be paid to the thyroid function of patients when abnormal platelet indices are found, and conversely, the consequences of abnormal platelet parameters such as elevated MPV lead to an increased occurrence of cardiovascular events, which should also be addressed in the AITD population.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022341823.
Topics: Humans; Hashimoto Disease; Mean Platelet Volume; Platelet Count; Graves Disease; Hyperthyroidism; Hypothyroidism
PubMed: 36618418
DOI: 10.3389/fimmu.2022.1089469 -
Frontiers in Immunology 2022Platelet (PLT) engages in immune and inflammatory responses, all of which are related to the prognosis of critically ill patients. Although thrombocytopenia at ICU...
OBJECTIVE
Platelet (PLT) engages in immune and inflammatory responses, all of which are related to the prognosis of critically ill patients. Although thrombocytopenia at ICU admission contributes to in-hospital mortality, PLT is repeatedly measured during ICU hospitalization and the role of longitudinal PLT trajectory remains unclear. We aimed to identify dynamic PLT trajectory patterns and evaluate their relationships with mortality risk and thrombocytopenia.
METHODS
We adopted a three-phase, multi-cohort study strategy. Firstly, longitudinal PLT trajectory patterns within the first four ICU days and their associations with 28-day survival were tested in the eICU Collaborative Research Database (eICU-CRD) and independently validated in the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Secondly, the relationships among PLT trajectory patterns, thrombocytopenia, and 28-day mortality were explored and validated. Finally, a Mortality GRade system for ICU dynamically monitoring patients (Mortality-GRID) was developed to quantify the mortality risk based on longitudinal PLT, which was further validated in the Molecular Epidemiology of Acute Respiratory Distress Syndrome (MEARDS) cohort.
RESULTS
A total of 35,332 ICU patients were included from three cohorts. Trajectory analysis clustered patients into ascending (AS), stable (ST), or descending (DS) PLT patterns. DS patients with high baseline PLT decline quickly, resulting in poor prognosis. AS patients have low baseline PLT but recover quickly, favoring a better prognosis. ST patients maintain low PLT, having a moderate prognosis in between ( = 1.26, 95% CI: 1.14-1.38, = 6.15 × 10; = 1.58, 95% CI: 1.40-1.79, = 1.41 × 10). The associations remained significant in patients without thrombocytopenia during the entire ICU hospitalization and were robust in sensitivity analyses and stratification analyses. Further, the trajectory pattern was a warning sign of thrombocytopenia, which mediated 27.2% of the effects of the PLT trajectory on 28-day mortality ( = 1.11, 95% CI: 1.06-1.17, = 9.80 × 10). Mortality-GRID well predicts mortality risk, which is in high consistency with that directly estimated in MEARDS ( = 0.98, = 1.30 × 10).
CONCLUSION
Longitudinal PLT trajectory is a complementary predictor to baseline PLT for patient survival, even in patients without risk of thrombocytopenia. Mortality-GRID could identify patients at high mortality risk.
Topics: Cohort Studies; Critical Illness; Humans; Intensive Care Units; Platelet Count; Respiratory Distress Syndrome; Thrombocytopenia
PubMed: 36059447
DOI: 10.3389/fimmu.2022.936662