Search results for "hemostasis"
showing 10 items of 120 documents
A bacterial metabolite, trimethylamine N-oxide, disrupts the hemostasis balance in human primary endothelial cells but no coagulopathy in mice
2019
: The gut microbial metabolite, trimethylamine N-oxide (TMAO), was previously reported to induce platelet hypersensitivity, which leads to thrombotic risk. However, the molecular mechanism underlying the effects of TMAO on endothelial cells (EC), which is the primary vessel wall contact with the lumen, remains unclear. Here, we investigated the impact of TMAO on procoagulant activity (PCA) in EC and mice, for a possible link between microbiota and coagulation. To test the PCA of TMAO in EC, we performed one-stage clotting assays and converted into PCA. Antitissue factor (TF) antibody was used to test the TF role in PCA. Quantitative PCR was performed to measure the TF, thrombomodulin, IL-6,…
Glucocorticoids as modulators of expression and activity of Antithrombin (At): potential clinical relevance.
2014
Abstract Introduction An inverse relationship has been reported between decreased postoperative Antithrombin (AT) plasmatic levels and the incidence of complications. We hypothesized that Nuclear Hormone Receptors could modulate the expression of SERPINC1 , encoding AT, through a Hormone Regulatory Element present in its promoter, and thus hormone analogs could be a pharmacological complement in surgical procedures to activate endogenous AT synthesis. Materials and Methods The expression of SERPINC1 was analyzed in HepG2 cells by quantitative RT-PCR and Western Blot. Two studies were conducted with (a) patients submitted to cardiac surgery with cardiopulmonary bypass receiving (n =17) or no…
Evaluation of bleeding risk and measurement methods in dental patients
2010
Objective: The present study explores bleeding manifestations in routine dental surgical procedures, evaluates the influence of antithrombotic drugs upon bleeding risk, and validates the efficiency of a clinical method for the measurement of bleeding. Material and method: A prospective observational study was made involving a cohort of 99 patients in the setting of normal clinical practice, with the added conduction of prior hematological tests including baseline hemostasis and platelet function, based on a new method (Multiplate System®). For evaluation of the bleeding manifestations, a clinical method was selected that evaluates bleeding on the basis of its duration and the hemostatic mea…
Non lipid, dose-dependent effects of pravastatin treatment on hemostatic system and inflammatory response
2000
Objectives: The aim of the present study was to evaluate the effects of pravastatin treatment on lipid, inflammation, and coagulation parameters in patients suffering from myocardial infarction with or without carotid atherosclerotic lesions (groups 1 and 2, respectively). Methods: In the first phase of the study, a cross-sectional comparison of lipid, inflammation, and coagulation parameters was performed between the patients and the control group (group 3). Highly significant differences in these parameters were observed, especially in group 1. In the second phase of the study, we assessed the effects of a persistent reduction in cholesterol synthesis induced by increasing doses of pravas…
Minor hepatic resection using heat coagulative necrosis
2009
Intra- and postoperative bleeding represents an extremely serious and frequent complication of hepatic surgery. In this study, we evaluated the effectiveness of a radiofrequency (RF) device using heat to cause coagulative necrosis of the hepatic parenchyma to control hemostasis in minor hepatic resection. Between December 2005 and November 2007, a study was conducted of 21 patients undergoing 22 hepatic resections with the RF-assisted technique. Sixteen of these were affected by hepatocellular carcinoma and five had liver metastases from colorectal cancer. Intraoperative blood loss, the need for blood transfusion, the complication rates, operating times, and the duration of postoperative h…
Murine tissue factor disulfide mutation causes a bleeding phenotype with sex specific organ pathology and lethality.
2019
Tissue factor is highly expressed in sub-endothelial tissue. The extracellular allosteric disulfide bond Cys186-Cys209 of human tissue factor shows high evolutionary conservation and in vitro evidence suggests that it significantly contributes to tissue factor procoagulant activity. To investigate the role of this allosteric disulfide bond in vivo, we generated a C213G mutant tissue factor mouse by replacing Cys213 of the corresponding disulfide Cys190-Cys213 in murine tissue factor. A bleeding phenotype was prominent in homozygous C213G tissue factor mice. Pre-natal lethality of 1/3rd of homozygous offspring was observed between E9.5 and E14.5 associated with placental hemorrhages. After b…
The pleiotropic effects of antiplatelet therapies
2019
Percutaneous coronary intervention is the most often used method for coronary revascularization. Stenting restores blood perfusion to ischemic areas, but it also causes mechanical disruption of the atheromatous plaque and the nearby endothelium, stimulating the activation of platelets. In a similar way, platelets are activated by thrombin exposure in the setting of plaque rupture. The interaction between platelets, oxidative stress and inflammation is an important factor determining the extent and severity of vascular dysfunction observed in these settings. Platelets activated by the vessel trauma release inflammatory and mitogenic mediators into the vascular microenvironment, activating le…
Efficacy of infiltrative local anesthesia and inferior alveolar nerve block in periapical surgery of lower premolars and molars : a preliminary report
2020
Background The aims of this study were: 1) compare the amount of anesthesia used with the anesthetic technique; 2) relate the quantity of anesthesia needed with the level of anxiety of the patient; 3) study the relationship between the anesthetic technique and the level of hemostasis; 4) correlate the amount of anesthesia with patient and tooth dependent variables. Material and Methods A randomized controlled trial was designed with two parallel groups according to the anesthetic technique: infiltrative local anesthesia (infiltrative group) and inferior alveolar nerve block (block group). The following variables were collected: sex, age, smoking habits, plaque index, symptoms, signs, positi…
Isoflavones and cardiovascular disease
2010
The specific profile of estrogens on cardiovascular risk, with limiting action on atherogenesis but a less clear protection on cardiovascular episodes, might be improved by other agonists of the estrogen receptor, such as isoflavones. By using a systematic search based on the electronic Medline database plus a hand-search of reference lists of selected review papers, we reviewed the rapidly growing body of experimental and clinical data that, on average, follow a pattern of benefit rather similar to estrogens. Experimental models have used endothelial and vascular smooth muscle cells, isolated arteries, and live animals, including monkeys. The clinical evidence arises from studies on the li…
Complement C5 but not C3 is expendable for tissue factor activation by cofactor-independent antiphospholipid antibodies
2018
The complement and coagulation cascades interact at multiple levels in thrombosis and inflammatory diseases. In venous thrombosis, complement factor 3 (C3) is crucial for platelet and tissue factor (TF) procoagulant activation dependent on protein disulfide isomerase (PDI). Furthermore, C5 selectively contributes to the exposure of leukocyte procoagulant phosphatidylserine (PS), which is a prerequisite for rapid activation of monocyte TF and fibrin formation in thrombosis. Here, we show that monoclonal cofactor-independent antiphospholipid antibodies (aPLs) rapidly activate TF on myelomonocytic cells. TF activation is blocked by PDI inhibitor and an anti-TF antibody interfering with PDI bin…