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1.
Mymensingh Med J ; 31(1): 107-111, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34999688

RESUMO

Platelets are involved in regeneration at sites of bony defect, apart from their function in coagulation. An autologous preparation platelet-rich plasma gel applied to sites of bony defects after surgical treatment of jaw cyst. This case-control study was conducted in Bangabandhu Sheikh Mujib Medical University (BSMMU) in the department of Oral and Maxillofacial Surgery from September 2017 to August 2018. Total 30 patients were chosen having jaw cyst. They were divided into 2 groups; Group A and Group B, where Group A got the platelet rich plasma, after removal of the cystic lesion; and Group B got the normal usual treatment. Platelet rich plasma gel was prepared using a standardized technique and applied to the surgical site of the Group A. The differences of radiographic changes between the two groups at 6th, 12th, 18th and 24th weeks after surgery were analyzed. Study showed significant changes in early bone regeneration in group A at 12th and 18th weeks post operatively. Platelet rich plasma induces early bone regeneration and it has proven successful outcome.


Assuntos
Cistos Maxilomandibulares , Plasma Rico em Plaquetas , Plaquetas , Regeneração Óssea , Estudos de Casos e Controles , Humanos , Cistos Maxilomandibulares/diagnóstico por imagem , Cistos Maxilomandibulares/cirurgia
2.
Biochim Biophys Acta Mol Basis Dis ; 1868(1): 166280, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34610471

RESUMO

Over the last decades, some members of the protein tyrosine phosphatase family have emerged as cancer promoters. Among them, the Low Molecular Weight Protein Tyrosine Phosphatase (LMWPTP) has been described to be associated with colorectal cancer liver metastasis and poor prostate cancer prognosis. Of importance in the process of cancer progression and metastasis is the interaction between tumor cells and platelets, as the latter are thought to promote several tumor hallmarks. Here, we examine to what extent LMWPTP expression in tumor cells affects their interaction with platelets. We demonstrate that the gene encoding LMWPTP is overexpressed in upper gastrointestinal (GI) cancer cell as well as colorectal cancer, and subsequently employ cell line models to show that the level of this phosphatase may be further augmented in the presence of platelets. We demonstrate that tumor-platelet interaction promotes GI tumor cell proliferation. Additionally, using know-down/-out models we show that LMWPTP expression in cancer cells contributes to a more efficient interaction with platelets and drives platelet-induced proliferation. These data are the first to demonstrate that phosphatases play a positive role in the tumor-promoting activities of platelets, with LMWPTP emerging as a key player promoting oncogenic phenotypic changes in tumor cells.


Assuntos
Plaquetas/metabolismo , Carcinogênese/genética , Neoplasias Gastrointestinais/genética , Proteínas Tirosina Fosfatases/genética , Proteínas Proto-Oncogênicas/genética , Plaquetas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Técnicas de Cocultura , Feminino , Neoplasias Gastrointestinais/patologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Peso Molecular , Metástase Neoplásica , Transdução de Sinais/genética , Microambiente Tumoral/genética
3.
Methods Mol Biol ; 2373: 201-212, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34520014

RESUMO

Mechanical circulatory support devices (MCSDs), although proved to be a pillar in the clinical setting of advanced heart failure, are afflicted by thromboembolic complications. Shear-mediated platelet activation has been recognized to drive thromboembolic events in patients implanted with MCSDs. Despite this, to date, a clinically reliable diagnostic test for assessing platelet response to stress stimuli is still missing. Here, we describe and apply the previously developed device thrombogenicity emulation methodology to the design of a microfluidic platform able to replicate shear stress profiles representative of MCSDs. The device-specific shear-mediated platelet activation is finally assessed by the platelet activity state assay, which measures real-time thrombin production, as a marker of platelet activation level. This technique can be employed to emulate the shear stress patterns of different MCSDs, such as mechanical heart valves, ventricular assist devices, and stents.


Assuntos
Coração Auxiliar , Microfluídica , Plaquetas , Coração Auxiliar/efeitos adversos , Humanos , Ativação Plaquetária , Tromboembolia , Trombose/etiologia
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120291, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34455376

RESUMO

Platelets have the functions of promoting blood coagulation and accelerating hemostasis, playing an important role in human body. It is of great medical significance to realize clinical rapid micro-detection of platelets by spectral analysis, which is the development direction of clinical detection in the future. However, due to the problem of unobvious characteristic of platelet absorption spectrum, the results of modeling and analysis cannot meet the clinical accuracy requirements. In order to improve the analysis accuracy, based on the "M+N" theory, this paper comprehensively considers the influence of the concentrations of measured component platelet and non-measured component hemoglobin on modeling analysis, and uses the method of selecting training set based on the concentration distribution of two components. At the same time, considering the characteristic of the linear model, the samples at both ends of the concentration of two components are selected as the training set, and the cubic term fitting method is combined to model and predict the concentration of platelet. The following experiments were designed: the training sets were selected by four different methods and used for modeling to predict the platelet concentration, and compared the modeling results of different methods. Through the modeling and prediction of 222 samples, the result showed that the method of selecting the training set with the concentration distribution of two components could effectively improve the prediction accuracy of the established model, and got a better model with better performance, the correlation coefficient Rc reached 0.63, which was 24.98% higher than the result of full modeling for all samples, and RMSE decreased by 10.02%. Considering the influence of non-measured components in modeling is of great significance to improve the prediction accuracy of measured components, and selecting samples from both ends of the concentration values of two components as the training set can further improve the performance and accuracy of the model.


Assuntos
Plaquetas , Humanos , Modelos Lineares , Análise Espectral
5.
Dis Markers ; 2021: 6304189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34900028

RESUMO

Background: Early identification of patients with severe coronavirus disease (COVID-19) at an increased risk of progression may promote more individualized treatment schemes and optimize the use of medical resources. This study is aimed at investigating the utility of the C-reactive protein to albumin (CRP/Alb) ratio for early risk stratification of patients. Methods: We retrospectively reviewed 557 patients with COVID-19 with confirmed outcomes (discharged or deceased) admitted to the West Court of Union Hospital, Wuhan, China, between January 29, 2020 and April 8, 2020. Patients with severe COVID-19 (n = 465) were divided into stable (n = 409) and progressive (n = 56) groups according to whether they progressed to critical illness or death during hospitalization. To predict disease progression, the CRP/Alb ratio was evaluated on admission. Results: The levels of new biomarkers, including neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, CRP/Alb ratio, and systemic immune-inflammation index, were higher in patients with progressive disease than in those with stable disease. Correlation analysis showed that the CRP/Alb ratio had the strongest positive correlation with the sequential organ failure assessment score and length of hospital stay in survivors. Multivariate logistic regression analysis showed that percutaneous oxygen saturation (SpO2), D-dimer levels, and the CRP/Alb ratio were risk factors for disease progression. To predict clinical progression, the areas under the receiver operating characteristic curves of Alb, CRP, CRP/Alb ratio, SpO2, and D-dimer were 0.769, 0.838, 0.866, 0.107, and 0.748, respectively. Moreover, patients with a high CRP/Alb ratio (≥1.843) had a markedly higher rate of clinical deterioration (log - rank p < 0.001). A higher CRP/Alb ratio (≥1.843) was also closely associated with higher rates of hospital mortality, ICU admission, invasive mechanical ventilation, and a longer hospital stay. Conclusion: The CRP/Alb ratio can predict the risk of progression to critical disease or death early, providing a promising prognostic biomarker for risk stratification and clinical management of patients with severe COVID-19.


Assuntos
Proteína C-Reativa/metabolismo , COVID-19/diagnóstico , Doença das Coronárias/diagnóstico , Hipertensão/diagnóstico , Doença Pulmonar Obstrutiva Crônica/diagnóstico , SARS-CoV-2/patogenicidade , Albumina Sérica Humana/metabolismo , Idoso , Área Sob a Curva , Biomarcadores/sangue , Plaquetas/patologia , Plaquetas/virologia , COVID-19/epidemiologia , COVID-19/mortalidade , COVID-19/virologia , China/epidemiologia , Comorbidade , Doença das Coronárias/epidemiologia , Doença das Coronárias/mortalidade , Doença das Coronárias/virologia , Progressão da Doença , Diagnóstico Precoce , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Humanos , Hipertensão/epidemiologia , Hipertensão/mortalidade , Hipertensão/virologia , Tempo de Internação/estatística & dados numéricos , Linfócitos/patologia , Linfócitos/virologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/patologia , Neutrófilos/virologia , Prognóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/mortalidade , Doença Pulmonar Obstrutiva Crônica/virologia , Curva ROC , Estudos Retrospectivos , SARS-CoV-2/crescimento & desenvolvimento , Índice de Gravidade de Doença , Análise de Sobrevida
6.
Clin Lab ; 67(12)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34910425

RESUMO

BACKGROUND: The aim of this study is to demonstrate the clinical significance of the platelet-to-lymphocyte ratio (PLR) and the ratio of aspartate aminotransferase (AST) to alanine aminotransferase (ALT) in patients with rheumatoid arthritis (RA). METHODS: A total of 215 patients with RA, 115 patients with osteoarthritis (OA), and 303 healthy controls (HCs) were included in this study. Data on the AST and ALT levels were collected from liver function test reports, and data on the number of platelets and lymphocytes were obtained from a routine blood analysis. Moreover, all the laboratory parameters of patients with RA, patients with OA, and HCs were retrospectively analyzed. RESULTS: The results obtained in this study showed that patients with RA had the highest PLR and AST/ALT ratio, whereas HCs had the lowest ratios (p < 0.05). Receiver operating characteristic (ROC) analysis showed that PLR + AST/ALT can produce high sensitivity and moderate specificity, distinguishing patients with RA from HCs, with a sensitivity of 91.1%, specificity of 75.3%, and area under the ROC curve (AUC) of 0.907. Spearman's analysis showed the PLR is negatively correlated with the erythrocyte sedimentation rate and C-reactive protein levels (p < 0.005). CONCLUSIONS: Combined detection of PLR and AST/ALT is better than each indicator individually and can improve the diagnostic efficiency of RA.


Assuntos
Artrite Reumatoide , Linfócitos , Artrite Reumatoide/diagnóstico , Plaquetas , Humanos , Neutrófilos , Estudos Retrospectivos
7.
Georgian Med News ; (320): 143-147, 2021 Nov.
Artigo em Russo | MEDLINE | ID: mdl-34897061

RESUMO

The materials used in the construction of implants contacting with blood should be resistant to thrombus formation. One of the stages of a thrombogenicity assessment of materials is to determine the number of platelets adhered to its surface during the exposure to flowing blood under ex viAvo conditions. The aim of this study was to develop a modified test for screening assessment of materials for their thrombogenicity in contact with native blood. For the purpose of the study, flow chambers of were developed, allowing to mountain simultaneously 16 material samples. The chamber was connected to the circulatory system of the experimental animal through arterial and venous ports in such a way that blood, passing through the chamber, returned to the animal. The exposure time was 1 min. After perfusion the samples were rinsed and stained. The number of platelets adhered per unit area was calculated automatically that allowed significant error diminution. A total of 9 experiments were carried out on pigs under ex vivo conditions. The method was validated using standard samples of pyrolytic carbon, VT-6 titanium, glass, and polytetrafluorethylene as reference materials. New materials for synthetic vascular prostheses have been investigated. The developed technique makes it possible to study the thrombogenicity of polymeric materials with sufficient reliability.


Assuntos
Plaquetas , Trombose , Animais , Prótese Vascular , Vidro , Reprodutibilidade dos Testes , Suínos , Trombose/diagnóstico
9.
PLoS One ; 16(12): e0261633, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34936674

RESUMO

We investigated the contributions of platelet microRNAs (miRNAs) to the rate of growth and regulation of gene expression in primary ectopic tumors using mouse models. We previously identified an inhibitory role for platelets in solid tumor growth, mediated by tumor infiltration of platelet microvesicles (microparticles) which are enriched in platelet-derived miRNAs. To investigate the specific roles of platelet miRNAs in tumor growth models, we implanted pancreatic ductal adenocarcinoma cells as a bolus into mice with megakaryocyte-/platelet-specific depletion of mature miRNAs. We observed an ~50% increase in the rate of growth of ectopic primary tumors in these mice compared to controls including at early stages, associated with reduced apoptosis in the tumors, in particular in tumor cells associated with platelet microvesicles-which were depleted of platelet-enriched miRNAs-demonstrating a specific role for platelet miRNAs in modulation of primary tumor growth. Differential expression RNA sequencing of tumor cells isolated from advanced primary tumors revealed a broad cohort of mRNAs modulated in the tumor cells as a function of host platelet miRNAs. Altered genes comprised 548 up-regulated transcripts and 43 down-regulated transcripts, mostly mRNAs altogether spanning a variety of growth signaling pathways-notably pathways related to epithelial-mesenchymal transition-in tumor cells from platelet miRNA-deleted mice compared with those from control mice. Tumors in platelet miRNA-depleted mice showed more sarcomatoid growth and more advanced tumor grade, indicating roles for host platelet miRNAs in tumor plasticity. We further validated increased protein expression of selected genes associated with increased cognate mRNAs in the tumors due to platelet miRNA depletion in the host animals, providing proof of principle of widespread effects of platelet miRNAs on tumor cell functional gene expression in primary tumors in vivo. Together, these data demonstrate that platelet-derived miRNAs modulate solid tumor growth in vivo by broad-spectrum restructuring of the tumor cell transcriptome.


Assuntos
Plaquetas/metabolismo , MicroRNAs/genética , Neoplasias Pancreáticas/genética , RNA Mensageiro/genética , Animais , Plaquetas/patologia , Carcinogênese/genética , Carcinogênese/patologia , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/patologia , Transcriptoma
10.
J Int Med Res ; 49(12): 3000605211061008, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34939884

RESUMO

OBJECTIVE: Coagulation indexes may be useful survival biomarkers for cervical cancer. This study evaluated the ability of hemoglobin, red blood cells (RBCs), platelets, and D-dimer levels to predict post-hysterectomy survival outcomes in patients with stage IA1 to IIA2 cervical cancer. METHODS: In this retrospective study, coagulation-related indexes were compared between the anemia and non-anemia groups. Independent variables were analyzed by the Cox proportional hazards model. Survival was assessed by the Kaplan-Meier method with the log-rank test. Mortality predictions were evaluated by receiver operating characteristic curves. RESULTS: Among this study's 1088 enrolled patients, 152 had anemia. The 10-year overall survival and recurrence-free survival rates were 90.8% and 86.5%, respectively. Hemoglobin, RBC, and the rate of abnormal platelet counts were significantly lower in the anemia group. Abnormal preoperative D-dimer was an independent factor for recurrence-free survival. Receiver operating characteristic curves showed that D-dimer had area under the curve of 0.734 (cut-off value: 0.685, sensitivity: 85.7%, and specificity: 64.0%). Hemoglobin and platelets had areas under the curves of 0.487 and 0.462, respectively. CONCLUSION: Preoperative D-dimer was the most effective prognostic predictor for patients with cervical cancer. The prognosis of patients with cervical cancer was poorer if their D-dimer levels were >0.685 mg/L.


Assuntos
Neoplasias do Colo do Útero , Plaquetas , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio , Hemoglobinas , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/cirurgia
11.
Blood ; 138(25): 2595-2596, 2021 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-34940817
12.
Cells ; 10(12)2021 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-34944034

RESUMO

Transcriptome analysis constitutes one of the major methods of elucidation of the genetic basis underlying the pathogenesis of various diseases. The post-transcriptional regulation of gene expression is mainly provided by microRNAs. Their remarkable stability in biological fluids and their high sensitivity to disease alteration indicates their potential role as biomarkers. Given the high mortality and morbidity of cardiovascular diseases, novel predictive biomarkers are sorely needed. Our study focuses for the first time on assessing potential biomarkers of acute coronary syndrome (ACS) based on the microRNA profiles of platelets. The study showed the overexpression of eight platelet microRNAs in ACS (miR-142-3p; miR-107; miR-338-3p, miR-223-3p, miR-21-5p, miR-130b-3p, miR-301a-3p, miR-221-3p) associated with platelet reactivity and functionality. Our results show that the combined model based on miR-142-3p and aspartate transaminase reached 82% sensitivity and 88% specificity in the differentiation of the studied groups. Furthermore, the analyzed miRNAs were shown to cluster into two orthogonal groups, regulated by two different biological factors. Bioinformatic analysis demonstrated that one group of microRNAs may be associated with the physiological processes of platelets, whereas the other group may be linked to platelet-vascular environment interactions. This analysis paves the way towards a better understanding of the role of platelet microRNAs in ACS pathophysiology and better modeling of the risk of ACS.


Assuntos
Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/genética , Biomarcadores/metabolismo , Plaquetas/metabolismo , MicroRNAs/metabolismo , Modelos Biológicos , Estudos de Casos e Controles , Análise Fatorial , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Ligação Proteica , Mapas de Interação de Proteínas/genética , Proteoma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Curva ROC , Reprodutibilidade dos Testes , Fatores de Risco
13.
Cells ; 10(12)2021 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-34943922

RESUMO

Previous mouse studies have shown the increased presence of platelets in the myocardium during early stages of myocarditis and their selective detection by MRI. Here, we aimed to depict early myocarditis using molecular contrast-enhanced ultrasound of activated platelets, and to evaluate the impact of a P2Y12 receptor platelet inhibition. Experimental autoimmune myocarditis was induced in BALB/c mice by subcutaneous injection of porcine cardiac myosin and complete Freund adjuvant (CFA). Activated platelets were targeted with microbubbles (MB) coupled to a single-chain antibody that binds to the "ligand-induced binding sites" of the GPIIb/IIIa-receptor (=LIBS-MB). Alongside myocarditis induction, a group of mice received a daily dose of 100 g prasugrel for 1 month. Mice injected with myosin and CFA had a significantly deteriorated ejection fraction and histological inflammation on day 28 compared to mice only injected with myosin. Platelets infiltrated the myocardium before reduction in ejection fraction could be detected by echocardiography. No selective binding of the LIBS-MB contrast agent could be detected by either ultrasound or histology. Prasugrel therapy preserved ejection fraction and significantly reduced platelet aggregates in the myocardium compared to mice without prasugrel therapy. Therefore, P2Y12 inhibition could be a promising early therapeutic target in myocarditis, requiring further investigation.


Assuntos
Plaquetas/metabolismo , Miocardite/patologia , Miocardite/fisiopatologia , Receptores Purinérgicos P2Y12/metabolismo , Volume Sistólico/fisiologia , Animais , Sítios de Ligação , Plaquetas/efeitos dos fármacos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Inflamação/patologia , Ligantes , Masculino , Camundongos Endogâmicos BALB C , Microbolhas , Miocardite/diagnóstico , Miocardite/diagnóstico por imagem , Miocárdio/patologia , Agregação Plaquetária/efeitos dos fármacos , Cloridrato de Prasugrel/farmacologia , Volume Sistólico/efeitos dos fármacos , Suínos
14.
Int J Mol Sci ; 22(24)2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34948438

RESUMO

COVID-19 infection is associated with a broad spectrum of presentations, but alveolar capillary microthrombi have been described as a common finding in COVID-19 patients, appearing as a consequence of a severe endothelial injury with endothelial cell membrane disruption. These observations clearly point to the identification of a COVID-19-associated coagulopathy, which may contribute to thrombosis, multi-organ damage, and cause of severity and fatality. One significant finding that emerges in prothrombotic abnormalities observed in COVID-19 patients is that the coagulation alterations are mainly mediated by the activation of platelets and intrinsically related to viral-mediated endothelial inflammation. Beyond the well-known role in hemostasis, the ability of platelets to also release various potent cytokines and chemokines has elevated these small cells from simple cell fragments to crucial modulators in the blood, including their inflammatory functions, that have a large influence on the immune response during infectious disease. Indeed, platelets are involved in the pathogenesis of acute lung injury also by promoting NET formation and affecting vascular permeability. Specifically, the deposition by activated platelets of the chemokine platelet factor 4 at sites of inflammation promotes adhesion of neutrophils on endothelial cells and thrombogenesis, and it seems deeply involved in the phenomenon of vaccine-induced thrombocytopenia and thrombosis. Importantly, the hyperactivated platelet phenotype along with evidence of cytokine storm, high levels of P-selectin, D-dimer, and, on the other hand, decreased levels of fibrinogen, von Willebrand factor, and thrombocytopenia may be considered suitable biomarkers that distinguish the late stage of COVID-19 progression in critically ill patients.


Assuntos
Plaquetas/fisiologia , COVID-19/sangue , Trombose/patologia , Coagulação Sanguínea , Transtornos da Coagulação Sanguínea/etiologia , Plaquetas/metabolismo , Plaquetas/virologia , COVID-19/metabolismo , Síndrome da Liberação de Citocina , Células Endoteliais/patologia , Produtos de Degradação da Fibrina e do Fibrinogênio , Hemostasia , Humanos , Inflamação , Fenótipo , Ativação Plaquetária/fisiologia , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Trombocitopenia/metabolismo , Trombose/metabolismo , Trombose/virologia
15.
Acta Vet Scand ; 63(1): 54, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34961516

RESUMO

Primary immune thrombocytopenia (ITP) is a cause of severe thrombocytopenia in dogs. Immunosuppressive corticosteroid drugs are frequently used in the management of ITP, but treatment failure may occur. Immunomodulatory and non-corticosteroid immunosuppressive drugs might improve outcomes from therapy either alone or in combination with corticosteroids. The objectives of this scoping review were (1) to evaluate the current evidence relating to immunomodulatory and immunosuppressive drug protocols in the treatment of canine ITP, and (2) to answer the clinical question, whether or not therapy with immunomodulatory or non-corticosteroid immunosuppressive drugs alone or in combination with corticosteroids could improve outcome, compared to therapy with corticosteroids alone. A literature search was performed in the electronic databases of Agricola, CAB Abstracts, Embase, Medline and Web of Science for publications in November 2019 and again February 1, 2021. Selection criteria were relatively strict and included peer-reviewed research papers reporting outcome measures from immunomodulatory and immunosuppressive drug protocols in the treatment of canine ITP with a pre-therapeutic mean or median platelet count < 50,000/µL as a strict criterion for inclusion. Studies were evaluated if they had an appropriate diagnostic work up to exclude underlying conditions. Outcome measures and adverse events were compared between drug protocols both within studies and between studies. The search identified 456 studies, with six studies being eligible for inclusion. The studies were mostly case series while two were randomized controlled trials. Level of evidence varied with an overall uncertain subject enrollment, small groups, inadequate description and variable use of drug protocols or outcome measures. For outcomes such as platelet recovery time and duration of hospitalization, an improvement was observed using adjunctive therapy (human intravenous immunoglobulin) compared to therapy with corticosteroids alone. For outcomes of complete platelet recovery time, survival (6-month), mortality and relapse, no improvement was observed using adjunctive drugs compared to corticosteroids alone. Specifically, therapy with mycophenolate mofetil alone and adjunctive azathioprine were associated with more severe adverse events compared to other drug protocols. Evidence relating to immunomodulatory and immunosuppressive drug protocols in the treatment of canine ITP was of variable quality. Future larger case-controlled trials are required for determination of optimal treatment protocols in canine ITP.


Assuntos
Doenças do Cão , Preparações Farmacêuticas , Púrpura Trombocitopênica Idiopática , Animais , Plaquetas , Doenças do Cão/tratamento farmacológico , Cães , Imunossupressores/uso terapêutico , Contagem de Plaquetas/veterinária , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/veterinária
16.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(6): 1087-1096, 2021 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-34970891

RESUMO

Fibrinogen (Fg) in human plasma plays an important role in hemostasis, vascular repair and tissue integrity. The surface chemistry of extracellular matrix or biological materials affects the orientation and distribution of Fg, and changes the exposure of integrin binding sites, thereby affecting its adhesion function to platelets. Here, the quantity, morphology and side chain exposure of Fg adsorbed on hydrophilic, hydrophobic and avidin surfaces were measured by atomic force microscopy (AFM) and flow cytometry (FCM), then the rolling behavior of platelets on Fg was observed through a parallel plate flow chamber system. Our results show that the hydrophobic surface leads to a large amount of cross-linking and aggregation of Fg, while the hydrophilic surface reduces the adsorption and accumulation of Fg while causing the exposure and spreading of the α chain on Fg and further mediating the adhesion of platelets. Fg immobilized by avidin / biotin on hydrophilic surface can maintain the monomer state, avoid over exposure and stretching of α chain, and bind to the platelets activated by the A1 domain of von Willebrand factor instead of inactivated platelets. This study would be helpful for improving the blood compatibility of implant biomaterials and reasonable experimental design of coagulation in vitro.


Assuntos
Fibrinogênio , Adesividade Plaquetária , Adsorção , Plaquetas , Humanos , Fator de von Willebrand
17.
PLoS One ; 16(12): e0261429, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34910783

RESUMO

BACKGROUND: Coagulation system is heavily involved into the process of infective endocarditis (IE) vegetation formation and can facilitate further embolization. In this study we aimed to assess the coagulation and platelet state in IE implementing a wide range of standard and global laboratory assays. We also aim to determine whether prothrombotic genetic polymorphisms play any role in embolization and mortality in IE patients. METHODS: 37 patients with IE were enrolled into the study. Coagulation was assessed using standard coagulation assays (activated partial thromboplastin time (APTT), prothrombin, fibrinogen, D-dimer concentrations) and integral assays (thromboelastography (TEG) and thrombodynamics (TD)). Platelet functional activity was estimated by flow cytometry. Single nuclear polymorphisms of coagulation system genes were studied. RESULTS: Fibrinogen concentration and fibrinogen-dependent parameters of TEG and TD were increased in patients indicating systemic inflammation. In majority of patients clot growth rate in thrombodynamics was significantly shifted towards hypercoagulation in consistency with D-dimers elevation. However, in some patients prothrombin, thromboelastography and thrombodynamics were shifted towards hypocoagulation. Resting platelets were characterized by glycoprotein IIb-IIIa activation and degranulation. In patients with fatal IE, we observed a significant decrease in fibrinogen and thrombodynamics. In patients with embolism, we observed a significant decrease in the TEG R parameter. No association of embolism or mortality with genetic polymorphisms was found in our cohort. CONCLUSIONS: Our findings suggest that coagulation in patients with infective endocarditis is characterized by general hypercoagulability and platelet pre-activation. Some patients, however, have hypocoagulant coagulation profile, which presumably can indicate progressing of hypercoagulation into consumption coagulopathy.


Assuntos
Endocardite/patologia , Ativação Plaquetária/genética , Ativação Plaquetária/fisiologia , Trombofilia/genética , Trombofilia/patologia , Adulto , Idoso , Plaquetas/fisiologia , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fibrinogênio/análise , Hemostasia/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial/métodos , Polimorfismo de Nucleotídeo Único/genética , Protrombina/análise , Tromboelastografia/métodos
18.
Bol Med Hosp Infant Mex ; 78(6): 557-564, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34934218

RESUMO

BACKGROUND: This study aimed to evaluate the neutrophil-lymphocyte (NLR) and platelet-lymphocyte (PLR) ratios as markers of perforated appendicitis. METHODS: We conducted a cross-sectional analytical study. We performed a secondary analysis of a population of pediatric patients who underwent appendectomy between 2017 and 2019 at the Regional Hospital of Ayacucho, Peru. Logistic regression models were used to analyze markers (NLR and PLR) and perforated appendicitis. Later, ROC (receiver operating characteristic) curves were constructed, and sensitivity, specificity, and likelihood ratios were estimated. RESULTS: We identified 31% of perforated appendicitis in 203 patients. A significant association was observed between perforated appendicitis and NLR values > 10.4 (odds ratio [OR]: 2.53; 95% confidence interval [95% CI]: 1.27-5.05) and PLR > 284 (OR: 2.11; 95% CI: 1.09-4.08) in the adjusted analysis. For these models, the areas under the curve were 0.74 (95% CI: 0.67 - 0.81) for both variables. With a cut-off point of 30% probability of perforated appendicitis, we observed sensitivity of 77.78% for both NLR and PLR (likelihood ratio +2.37 and +2.14, respectively), and specificity of 67.14% and 63.57% for NLR and PLR (likelihood ratio -0.33), respectively. CONCLUSIONS: Our study showed a significant association between NLR and PLR and acute perforated appendicitis. Future studies should validate the model and corroborate the performance of these markers.


Assuntos
Apendicite , Plaquetas , Criança , Estudos Transversais , Humanos , Linfócitos , Estudos Retrospectivos
19.
Scand J Immunol ; 94(5): e13097, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34940978

RESUMO

COVID-19 is a global pandemic with a daily increasing number of affected individuals. Thrombosis is a severe complication of COVID-19 that leads to a worse clinical course with higher rates of mortality. Multiple lines of evidence suggest that hyperinflammation plays a crucial role in disease progression. This review compiles clinical data of COVID-19 patients who developed thrombotic complications to investigate the possible role of hyperinflammation in inducing hypercoagulation. A systematic literature search was performed using PubMed, Embase, Medline and Scopus to identify relevant clinical studies that investigated thrombotic manifestations and reported inflammatory and coagulation biomarkers in COVID-19 patients. Only 54 studies met our inclusion criteria, the majority of which demonstrated significantly elevated inflammatory markers. In the cohort studies with control, D-dimer was significantly higher in COVID-19 patients with thrombosis as compared to the control. Pulmonary embolism, deep vein thrombosis and strokes were frequently reported which could be attributed to the hyperinflammatory response associated with COVID-19 and/or to the direct viral activation of platelets and endothelial cells, two mechanisms that are discussed in this review. It is recommended that all admitted COVID-19 patients should be assessed for hypercoagulation. Furthermore, several studies have suggested that anticoagulation may be beneficial, especially in hospitalized non-ICU patients. Although vaccines against SARS-CoV-2 have been approved and distributed in several countries, research should continue in the field of prevention and treatment of COVID-19 and its severe complications including thrombosis due to the emergence of new variants against which the efficacy of the vaccines is not yet clear.


Assuntos
Artérias/patologia , Plaquetas/imunologia , COVID-19/imunologia , Endotélio Vascular/imunologia , Inflamação/imunologia , SARS-CoV-2/fisiologia , Trombose Venosa/imunologia , Animais , Anticoagulantes/uso terapêutico , Plaquetas/virologia , COVID-19/complicações , Endotélio Vascular/virologia , Humanos , Inflamação/complicações , Fenótipo , Trombose , Trombose Venosa/etiologia , Trombose Venosa/prevenção & controle
20.
Rev Cardiovasc Med ; 22(4): 1685-1691, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34957811

RESUMO

Coronavirus disease 2019 (COVID-19) is associated with various hemostatic abnormalities requiring constant search for better delicate antithrombotic management in these high-risk patients. The choice and the optimal dose of anticoagulant is important, but unclear, especially for mild COVID-19. Enoxaparin has been tested in several COVID trials with mixed results regarding hard clinical outcomes including mortality. We analyzed clinical, laboratory data and changes in platelets, erythrocytes and leukocytes by scanning electron microscopy on admission and at hospital discharge in patients with confirmed COVID-19 treated with enoxaparin (n = 31) and matched healthy controls (n = 32) in a retrospective observational study. The data were triaged by enoxaparin dose comparing 40 mg/daily prophylactic enoxaparin dose (PED) with 80 mg/daily therapeutic (TED) regimens. All patients experienced mild disease, none required pulmonary support, and all survived. The impact of enoxaparin dose was prominent for platelets and erythrocytes, but less evident for leukocytes. PED was associated with significant platelet activation, diminished numbers of silent nonactive discoid cells, and increased number and size of platelet microaggregates with leukocyte involvement. In contrast, TED did not cause extra platelet activation, while circulating platelet microaggregates were smaller and lacking leukocytes in their construction. PED caused significant increase of erythrocyte-platelet aggregates formation, and numerically higher proportion of circulating echinocytes. TED was associated with significant decrease of rouleaux sludge formation compared to only some trend after PED. Changes in leukocytes were less dependent on enoxaparin dose. However, PED has been associated with enhanced aggregate formation in 7 out of 10 patients, while trap net formation has been decreased in 17 out of 21 TED patients. We conclude that over hospital stay TED was superior to PED in patients with mild COVID-19. The inability of PED to adequately protect major circulating blood cells is probably due to enhanced clearance or/and diminished bioavailability of enoxaparin during COVID. These retrospective observational small sample size data may be relevant to better understanding of the mixed results in controlled outcome-driven trials exploring optimal COVID-19 anticoagulant strategies.


Assuntos
COVID-19 , Anticoagulantes/efeitos adversos , Plaquetas , Enoxaparina/efeitos adversos , Humanos , Fenótipo , Estudos Retrospectivos , SARS-CoV-2
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