Pregnancy is associated with a significant procoagulant shift in the hemostatic system balance as well as other metabolic changes. Pregnancy can thereby provoke manifestation of otherwise dormant ...disorders of hemostasis (e.g., thrombophilia), or even cause new, pregnancy-specific disorders (e.g., HELLP syndrome). Application and interpretation of laboratory assays of hemostasis in pregnancy is particularly challenging, because normal physiological ranges are no longer applicable, and because the most dangerous and complex changes are not detected by classic routine coagulation/platelet assays. New global assays of coagulation and of platelet-dependent hemostasis appear to be promising in this respect, but are still far from clinical practice and rarely appear in current patient management guidelines. These global assays require a high level of research to identify their relationship to clinically significant outcomes. Here, we review the state-of-the-art knowledge of the molecular changes in the hemostatic system in normal pregnancy and during pregnancy-related complications (preeclampsia, thrombotic microangiopathies, antiphospholipid syndrome, etc.). We also discuss the sensitivity of various classic and innovative assays to these pregnancy-associated changes, and describe current and potential future applications of these assays in meeting specific clinical needs.
In this work, we present a new method-Thrombodynamics-4D-for the assessment of both plasma and platelet contributions to clotting. Thrombodynamics-4D potentially allows for the determination of ...plasma or platelet disorders and the effects of various drugs on plasma clotting or on platelet procoagulant function. In this assay, clot formation in platelet-rich plasma or platelet-free plasma supplemented with phospholipids is activated with tissue factor immobilized on a surface. Spatial fibrin clot growth and thrombin concentration dynamics are registered by measuring light scattering of the fibrin clot and fluorescence of the product formed by cleavage of the synthetic fluorogenic substrate by thrombin, respectively. Here, we describe the preanalytical requirements, measurement methodology and calculation principles of assay parameters. Preanalytical and analytical variability and reference ranges of the assay are given. Additionally, we show some clinical examples, which determine the effect of anticoagulants, measure clotting dysfunction in patients with platelet or coagulation disorders and evaluate the effect of surgery.
Preterm newborns are at thrombohemorrhagic risk during the early neonatal period. Taking into account the lack of informative tools for the laboratory diagnosis of hemostasis disorders in newborns, ...our goal was to determine the baseline values of thrombodynamics and platelet functional activity in healthy term and moderately preterm newborns during the early neonatal period future potential clinical use of these tests.
Coagulation was assessed using an integral assay of thrombodynamics and standard coagulation assays, and platelet functional activity was estimated by flow cytometry.
Hypercoagulation of newborns, represented by a significantly higher clot growth velocity and the presence of spontaneous clots in the thrombodynamics, was combined with platelet hypoactivity. Granule release, phosphatidylserine exposure, and the ability to change shape upon activation were decreased in the platelets of moderately preterm newborns. The platelet function remained at the same level over the first four days of life, whereas the hypercoagulation became less pronounced.
The hemostasis of newborns is characterized by hypercoagulation combined with reduced platelet functional activity. Moderately preterm and term newborns do not differ in the parameters of coagulation, while some of the functional responses of platelets are lower in moderately preterm newborns than in term.
Activated platelets provide phospholipid surface and secrete coagulation factors, enhancing blood clotting. We investigated the role of platelets in the regulation of blood coagulation spatial ...dynamics. We activated blood clotting with tissue factor-bearing (TF) surface in platelet-rich plasma (PRP) or platelet-free plasma (PFP). When blood coagulation was initiated by high TF density, clot growth rate (V) in PRP (2 × 105/μL platelets) was only 15 % greater than in PFP. Spatial distribution of thrombin in PRP had a peak-like shape in the area of the fibrin clot edge, while in PFP thrombin was distributed in the shape of descending plateau. Platelet inhibition with prostaglandin E1 or cytochalasin D made spatial thrombin distribution look like in the case of PFP. Inhibition of blood coagulation by natural endogenous inhibitor heparin was diminished in PRP, while the effect of the exogenous or artificial inhibitors (rivaroxaban, nitrophorin, hirudin) remained undisturbed in the presence of platelets. Ten times decrease of the TF surface density greatly depressed blood coagulation in PFP. In PRP only clotting initiation phase was, while the propagation phase remained intact. Coagulation factor deficiency greatly reduced amount of thrombin and decreased V in PFP rather than in PPR. Thus, platelets were redundant for clotting in normal plasma under physiological conditions but provided robustness of the coagulation system to the changes in initial conditions.
•Platelets were redundant for clotting in normal plasma under physiological conditions.•Platelets provided robustness of the coagulation system to the changes in initial conditions.•Platelets were different from artificial lipids in effect on the thrombin generation.
The degradation of two isomeric three-ringed polycyclic aromatic hydrocarbons by the white rot fungus Pleurotus ostreatus D1 and the litter-decomposing fungus Agaricus bisporus F-8 was studied. ...Despite some differences, the degradation of phenanthrene and anthracene followed the same scheme, forming quinone metabolites at the first stage. The further fate of these metabolites was determined by the composition of the ligninolytic enzyme complexes of the fungi. The quinone metabolites of phenanthrene and anthracene produced in the presence of only laccase were observed to accumulate, whereas those formed in presence of laccase and versatile peroxidase were metabolized further to form products that were further included in basal metabolism (e.g. phthalic acid). Laccase can catalyze the initial attack on the PAH molecule, which leads to the formation of quinones, and that peroxidase ensures their further oxidation, which eventually leads to PAH mineralization.
A. bisporus, which produced only laccase, metabolized phenanthrene and anthracene to give the corresponding quinones as the dominant metabolites. No products of further utilization of these compounds were detected. Thus, the fungi's affiliation with different ecophysiological groups and their cultivation conditions affect the composition and dynamics of production of the ligninolytic enzyme complex and the completeness of PAH utilization.
Display omitted
•Degradation of phenanthrene and anthracene by wood- and soil-inhabiting basidiomycetes followed the same scheme.•The fate of quinone metabolites is determined by the composition of the ligninolytic enzyme complexes of the fungi.•Laccase can catalyze the initial attack on the PAH molecule, leading to the formation of quinones.•Peroxidase ensures the further oxidation of the formed quinones leading to their involvement to basal metabolism.
Seventeen 1,4‐benzoxazin‐2‐ones bearing the enaminone moiety and three of their analogs were tested for the antibacterial activity against Mycobacterium tuberculosis (H37Rv). Minimal bactericidal ...concentrations (MBCs) were determined after 41 days of incubation by BACTEC. 1,4‐Benzoxazin‐2‐ones bearing the unsubstituted benzo moiety showed the most promising activities (MBC = 5.00 µg/ml). For most active compounds, antibacterial activities were determined daily during the 41 days. The most promising compound showed a bacteriostatic effect at a concentration of 0.31 µg/ml on Day 4 of incubation, 0.62 µg/ml on Day 6, 2.50 µg/ml on Day 9, and 5.00 µg/ml on Day 41. All studied compounds, along with some of their reported analogs, were docked to 35 proteins of M. tuberculosis to find their potent targets in these organisms. As a result of reverse docking, aspartate 1‐decarboxylase, panD, was selected as the most appropriate target. Docking of the most active compounds to mutant panD from pyrazinamide‐resistant strains of M. tuberculosis implies that they would not be active against these strains. Considering that most of pyrazinamide clinical resistance cases are due to loss‐of‐function mutations in pyrazinamidase, pncA, compounds from this study could be useful drugs for the treatment of some cases of pyrazinamide‐resistant tuberculosis.
1,4‐Benzoxazin‐2‐ones bearing the enaminone moiety were tested for the antibacterial activity against Mycobacterium tuberculosis (H37Rv). Minimal bactericidal concentrations were determined by BACTEC. The most promising compound showed bacteriostatic effects at a concentration of 0.31 µg/ml on Day 4 of incubation and at 5.00 µg/ml on Day 41. As a result of reverse docking, aspartate 1‐decarboxylase (panD) was selected as the most appropriate target.
The incidence of venous thromboembolism (VTE) after cesarean section is up to 0.6%, and the widespread use of cesarean section draws attention to this group. The dosage and duration of ...low-molecular-weight heparin (LMWH) prophylaxis after delivery is estimated by anamnestic risk-scales; however, the predictive potency for an individual patient's risk can be low. Laboratory hemostasis assays are expected to solve this problem. The aim of this study was to estimate the potency of tests to reflect the coagulation state of patients receiving LMWH in the early postpartum period.
We conducted an observational study on 97 women undergoing cesarean section. Standard coagulation tests (Fg, APTT, prothrombin, D-dimer), an anti-Xa assay, rotation thromboelastometry and thrombodynamics/thrombodynamics-4D were performed. Coagulation assay parameters were compared in groups formed in the presence or absence of LMWH to estimate the laboratory assays' sensitivity to anticoagulation.
Coagulation assays revealed hypercoagulation after delivery and a tendency toward normalization of coagulation during early postpartum. The thromboprophylaxis results revealed a higher percentage of coagulation parameters within the normal range in the LMWH group.
This research is potentially beneficial for the application of thrombodynamics and thrombodynamics-4D in monitoring coagulation among patients with high VTE risk who receive thromboprophylaxis with heparin.
The ability of the litter-decomposing basidiomycete
Stropharia rugosoannulata
DSM 11372 to degrade a wide range of structurally different environmental pollutants such as polycyclic aromatic ...hydrocarbons (PAHs: phenanthrene, anthracene, fluorene, pyrene, and fluoranthene), synthetic anthraquinone dyes containing condensed aromatic rings, environmentally relevant alkylphenol and oxyethylated alkylphenol representatives, and oil was demonstrated within the present study. 9,10-Anthraquinone, phenanthrene-9,10-quinone, and 9-fluorenone were identified as products of anthracene, phenanthrene, and fluorene degradation, respectively. Fungal degradation was accompanied by the production of the ligninolytic enzymes: laccase and Mn peroxidase, suggesting their involvement in pollutant degradation. Extracellular polysaccharide(s) (EPS) and emulsifying compound(s) were concomitantly produced. EPS composed of mannose, glucose, and galactose was isolated from the cultivation medium, and its effects on catalytic properties of purified laccase from
S. rugosoannulata
(the dominating ligninolytic enzyme under the applied conditions) were studied. A simultaneous decrease of K
M
and V
max
values observed for the enzymatic oxidation of non-phenolic (2,2-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) diammonium salt; ABTS) and phenolic compounds (2,6-dimethoxyphenol) in presence of EPS suggest an interaction of EPS and laccase resulting in a modulation of the catalytic performance of the enzyme, which has, to the best of our knowledge, not been reported before. In line with such a modulation, the laccase-catalyzed oxidation of natural aromatic compounds (veratryl alcohol, adlerol) and environmental pollutants (the alkylphenol representative nonylphenol, the diphenylmethane derivative bisphenol A, and the PAH representative anthracene) was found to be enhanced in presence of EPS. The relevance of such effects for real environmental processes and their implications remain to be investigated.
Graphical abstract
Display omitted
•Biological characteristics and NMR relaxometry parameters were studied.•Microwave radiation can influence on structural dynamic state of the molecular system.•The mechanism of ...microwave radiation influence on living systems has been proposed.•This mechanism associated with the absorption of acceptor molecules energy.
The research investigates the mechanism of microwave radiation effects on biological characteristics and structural-dynamic parameters of a sensor bioluminescence system. The research objects are a sterile growth medium (fish meal hydrolisate) and a bacterial culture. It has been established that irradiation causes changes of the growth medium spectral properties within the range of 200–350nm. Changes take place in the intensity and character of luminescence, as well as in relaxation parameters of nuclear magnetic resonance, growth characteristics of the bacterial culture, its cellular morphology and surface topology. The research results enabled us to establish the mechanisms of primary molecular processes that occur when the bacterial culture is exposed to microwave radiation. Transformation of the dynamic-structural state of adsorbed water phases on biopolymer surfaces has been found to be the key factor in the mechanism of microwave effects on living and water-containing objects.
PDF
