Control of fibrinolytic drug injection via real-time ultrasonic monitoring of blood coagulation
Control of fibrinolytic drug injection via real- time ultrasonic monitoring of blood coagulation
Dmitry A. Ivlev 0 1
Shakhla N. Shirinli 1
Konstantin G. Guria 1
Svetlana G. Uzlova 0 1
Georgy Th. GuriaID 0 1
0 National Research Center for Hematology , Moscow , Russia , 2 Moscow Institute of Physics and Technology , Dolgoprudny , Russia
1 Editor: Alexander V. Panfilov , Universiteit Gent , BELGIUM
In the present study, we investigated the capabilities of a novel ultrasonic approach for realtime control of fibrinolysis under flow conditions. Ultrasonic monitoring was performed in a specially designed experimental in vitro system. Fibrinolytic agents were automatically injected at ultrasonically determined stages of the blood clotting. The following clots dissolution in the system was investigated by means of ultrasonic monitoring. It was shown, that clots resistance to fibrinolysis significantly increases during the first 5 minutes since the formation of primary micro-clots. The efficiency of clot lysis strongly depends on the concentration of the fibrinolytic agent as well as the delay of its injection moment. The ultrasonic method was able to detect the coagulation at early stages, when timely pharmacological intervention can still prevent the formation of macroscopic clots in the experimental system. This result serves as evidence that ultrasonic methods may provide new opportunities for real-time monitoring and the early pharmacological correction of thrombotic complications in clinical practice.
Monitoring and timely correction of hemostasis is a crucial medical task [
]. A number of
severe thrombotic pathologies, such as myocardial infarction and stroke, might occur suddenly
and develop very rapidly [
]. In these cases large thrombi occluding blood flow in major
arteries can be formed during several minutes [
]. That is why prompt and efficient techniques
for hemostasis monitoring are needed.
Over the past two decades turnaround times of clotting tests were substantially reduced by
introduction of so-called point-of-care techniques [
]. Novel methods for on-line ex vivo
monitoring of hemostasis are actively developed [
]. A logical step towards real-time control of
hemostasis would be creation of the technique for direct in vivo monitoring of intravascular
One of the possible approaches to creation of such a technique is the use of ultrasonic
methods. The idea for applying ultrasonic methods to detect blood coagulation was proposed quite
data collection and analysis, decision to publish, or
preparation of the manuscript.
long ago, at first for in vitro measurements [
]. In recent years, due to developments in
modern ultrasonic equipment, this area of research has become active again [
]. Various research
teams have offered several ultrasonic techniques for the registration of blood coagulation in
]. More recently capabilities of ultrasonic methods for in vivo detection of blood
coagulation were demonstrated in animal experiments [
It is essential that ultrasonic methods can detect blood coagulation under flow conditions
similar to those that take place in major arteries of human body [
]. This fact reveals the
possible application of ultrasonic methods for non-invasive monitoring of coagulation
processes in clinical practice .
Efficient control of hemostasis implies both its monitoring and means for its
pharmacological correction. Usually monitoring can be performed with routine coagulation tests and
correction can be achieved by use of anticoagulant drugs [
]. But in acute situations, then
formation of arterial thrombi has already started and progress rapidly, coagulation tests are
already late and anticoagulants are not capable of thrombi dissolution. In these situations the
last line of defense remaining is thrombolytic therapy [
]. Its efficiency drastically
depends on the delay after the onset of coagulation processes [
]. A method for real-time
monitoring of the onset of intravascular blood coagulation might be very useful in these acute
situations for the reduction of onset-to-treatment time.
In the present work we investigated possible benefits of ultrasonic detection of early stages
of blood coagulation for fibrinolytic dissolution of forming thrombi. To do so, we designed a
special experimental setup for the ultrasonic monitoring of blood coagulation under intensive
flow conditions in vitro. This setup allowed us to monitor blood coagulation in real time and
to perform an automated injection of a fibrinolytic drug at precisely determined stages of the
coagulation process. Our experiments showed the following:
1. The ultrasonic method used enables the reliable registration of blood coagulation and
following fibrinolytic dissolution of clots. The method facilitates the qualitative evaluation of
the efficiency of various fibrinolytic influences and enables the comparison of different
2. The fibrinolytic resistance of clots formed under flow conditions increases significantly
over the first few minutes of their formation;
3. An immediate injection of a fibrinolytic drug after the ultrasonic registration of the onset of
coagulation is able to prevent the formation of large clots in the experimental system.
Materials and methods
This study was approved by the Institutional Committee of Blood Donation and Blood
Processing Problems at the National Research Center for Hematology (Permit number: 5/2016).
This study was performed with blood received from healthy donors who provided written
informed consent before blood collection in accordance with Russian Federal Law No 125 on
July 20, 2012. All methods were carried out in accordance with relevant guidelines and
regulations (The Order of Russian Health Care Ministry No 183n on April 02, 2014).
Whole blood and blood plasma were used in the experiments. The blood and fresh frozen
plasma were provided by the Division of Blood and Blood Components Collection and Storage
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of the National Research Center for Hematology. Blood was preserved in Imuflex (Terumo
Europe NV, Belgium) containers with citrate phosphate dextrose (CPD) anticoagulant
solution. Plasma was separated from whole blood by centrifugation at 5000 g for 7 minutes.
To initiate coagulation several types of activators were used: 50 ?l of 1% kaolin suspension
(NPO-Renam, Russia), 50 ?l of thromboplastin solution, diluted by 12 times with normal
saline (NPO-Renam, Russia) or 10% calcium chloride solution (Mapichem AG, Switzerland).
Unless otherwise specified, activation of coagulation was initiated by injection of 600?800 ?l of
10% calcium chloride solution.
Three different types of fibrinolytic drugs were used in the experiments: streptokinase
(Streptokinaza, Belmedpreparaty, Belarus), tissue-type plasminogen activator (Actilyse,
Boehringer Ingelheim International, Germany) and urokinase (Urokinase, Medac GmbH,
Germany). The dosages of the fibrinolytic drug were varied in different experiments, while the
volume of the fibrinolytic solution injected into the experimental system (0.5 ml) was kept
The principal scheme of the experimental setup is shown in Fig 1. A closed system of flexible
transparent silicone tubes (1 in Fig 1) was filled with either blood or blood plasma. The inner
diameter of the tube was 4 mm, and the total volume of the experimental system was 18 ml.
The flow of liquid in the system was generated by a peristaltic pump, Elpan type 372.1 (2 in Fig
1). The mean velocity of the flow was kept at a rate of 20 cm/sec (shear rate up to 400 s-1). The
activators of coagulation were injected in flowing blood directly when experiment started. All
experiments were performed at the room temperature, 24 ? 2?C.
In the experiments with blood plasma, the processes of coagulation and fibrinolysis were
registered both optically and acoustically. In the experiments with whole blood, due to its
optical opacity, the registration was conducted only through the acoustic channel. Optical
registration was performed in the transmitted light with a digital camcorder, GoPro HERO 3
(Woodman Labs, Inc., USA) (3 in Fig 1). A macro lens with an optical power of 21 diopters
was used to focus the camcorder on the tube. The tube was held within the focal plane of the
camera by a special screw clamp. The same screw clamp was used to create an area of local
narrowing in the tube, beyond which a stagnation zone appeared in the flow. In several
experiments, such a stagnation zone was created to facilitate the optical registration of fibrin
microemboli, which form at an early stage of coagulation.
Acoustic registration was performed via an ultrasonic scanner Vingmed SD50 (Vingmed
Sound; Norway) working in a Doppler mode at a frequency of 5 MHz (4 in Fig 1). To reduce
the signal loss, the ultrasonic sensor (5 in Fig 1) together with a section of the tube system, was
immersed in a bath filled with degassed water. The data from the optical and acoustical
registration were recorded on a personal computer (6 in Fig 1).
A custom automated drug-injector (7 in Fig 1) was designed to perform the infusion of
fibrinolytic drugs into the experimental system. The injector was connected to the computer
via a Bluetooth channel. Following a signal from the computer, the injector delivered a
fibrinolytic agent into the system in a precisely controlled and reproducible manner. The injection
was performed gradually over 6 seconds, which was roughly equal to the turnover time of the
liquid within the experimental system.
A special computer program was written in Python for real-time data analysis and the
control of drug-injector operations. The Doppler shift of the ultrasonic signal was transferred
from the scanner to the computer, digitized in a format of 44100 Hz, 16 bit and subjected to
filtration by a second-order Butterworth filter with a passband from 200 to 1600 Hz [
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Subsequently, the modulus of the amplitude of the filtered acoustic signal was averaged for
2-second time intervals. This value, indicated below as the averaged modulus of amplitude
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(AMA), was used for the monitoring of blood coagulation and fibrinolysis in the system.
Upon the increase in AMA above a certain threshold, the program sent a command signal to
the drug-injector to perform the injection. The threshold value of AMA was defined basing on
a series of preliminary experiments as the background level of AMA in the beginning of the
experiment multiplied by a predefined coefficient (equal to 2 for blood plasma and 1.3 for
Calculation of fibrinolysis efficiency index
The efficiency of fibrinolytic processes was assessed basing on the data from the acoustic
registration after the end of each experiment. The area between the upper and the lower envelopes
of the AMA curve was calculated for a time period of 60 minutes after the registration of the
coagulation onset. This value calculated for the particular experiment was denoted as Sexp,
while Sref stands for the respective value calculated for a reference experiment with the blood
(blood plasma) of the same donor, but with normal saline instead of a fibrinolytic drug
injected. Finally, fibrinolysis efficiency index (FEI) was calculated with the following formula:
FEI ? 1
It should be noted that Sexp is proportional to the integrated intensity of the acoustic signal
reflected by macroscopic clots in the system during the experiment. The faster the dissolution
of fibrin clots, the smaller the value of Sexp. Accordingly, FEI tends to one in cases of the
immediate dissolution of all fibrin clots and is close to zero in cases of the complete absence of lysis
in the experimental system.
Changes in the acoustic signal caused by the development of coagulation
In the experiments with blood plasma, the changes in the acoustic signal were found to be
correlated with the coagulation processes that were detected optically. The time course of AMA
changes during a typical experiment with blood plasma is shown in Fig 2. The four distinct
characteristic stages of the coagulation processes observed in all experiments are marked in Fig 2.
Stage ?0? in Fig 2 corresponds to the lag phase that precedes the appearance of the first
optically detectable fibrin microemboli in the system. This stage lasts for 10?20 minutes after
the addition of coagulation activator to the plasma. The AMA value during this stage remained
practically unchanged, and its fluctuations did not exceed 15% of the initial background level.
After the lag phase, the rapid formation of multiple fibrin microemboli in the flow begins
(stage ?I? in Fig 2). The movement of microemboli in the flow at this stage visually resembles a
snow-storm. The increase in the amount of microemboli in the flow was accompanied by a
drastic increase in the intensity of the reflected ultrasonic signal. A four-fold to six-fold
increase in the AMA took place.
At 30?60 seconds following the appearance of the first microemboli, fibrin flakes that were
several millimeters in size were formed in the system. During the following few minutes,
gradual formation of larger aggregates took place in the system (stage ?II? in Fig 2). This process
was accompanied by the appearance of AMA oscillations, which were caused by single
aggregates of various sizes passing in front of the ultrasonic sensor. The increase in the size of single
clots led to the amplification of AMA oscillations at this stage.
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Fig 2. A typical time course of AMA (averaged modulus of amplitude of the acoustic signal) changes during coagulation in blood
plasma. The four successive characteristic stages of the process are marked with numbers (0, I, II, III).
Eventually, the mutual aggregation of fibrin flakes and microemboli led to the formation of
several large macroscopic clots (stage ?III? in Fig 2). The decrease in the number of clots in the
system was accompanied by a decline in the lower envelope of the AMA plot. When the lower
envelope of the AMA reached the initial background level of the AMA, no more
sound-reflecting micro-aggregates remained in the flow. By that time, only several large clots remained in
the system, causing large-amplitude oscillations in the AMA. These macroscopic clots were up
to 10 cm in length and, in some experiments, were capable of occluding the vessel lumen
completely, blocking flow.
Sample clips of a video recording of the coagulation process in blood plasma, representing
all four characteristic stages, can be seen in S1 Video (see also S1 Fig). The video sequence is
accompanied by a corresponding graph of AMA versus time. The Doppler shift in the
ultrasonic signal is given as a soundtrack of this video record, enabling the coagulation processes
developing in the system to literally be heard ?with the naked ear?.
Acoustic registration of drug-induced fibrinolysis
In Fig 3, the typical curves of AMA versus time for the experiments with fibrinolytic drug
injections are presented in comparison with the reference curves obtained for the experiments
in which no fibrinolytic drug was injected. In all cases final concentrations of fibrinolytics in
the system after injection are indicated. The graphs for the experiments with blood plasma are
given in Fig 3A and 3B, and those for the experiments with whole blood, in Fig 3C and 3D. It
has been established that lysis of fibrin clots is reflected in corresponding changes in the
acoustic signal. represents total reflection of ultrasonic signal by fibrin clots present in the flow, i.e.
macroscopic and microscopic clots. Dissolution of macroscopic clots is reflected in decrease of
AMA oscillations. While dissolution of micro-clots is manifested by decrease of the lower
envelope of AMA curve (see S1 Text for details).
The data presented indicate that the injection of a fibrinolytic drug at the initial stage of the
coagulation process can prevent the formation of large clots in the experimental system.
Moreover, it can be seen from Fig 3 that the practically complete lysis of all fibrin aggregates
occurred in 5?7 minutes after injection of the fibrinolytic agent. Similar results were obtained
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Fig 3. Typical curves of AMA (averaged modulus of amplitude of the acoustic signal) versus time for the experiments with a complete lysis of all macroscopic clots
(black) in comparison with the reference curves obtained for the experiments in which no fibrinolytic drug was injected (gray). The moments of the injection of
streptokinase are marked on the graphs with bold round markers. (a,b)?experiments with blood plasma, final concentration of streptokinase? 150 IU/ml; (c,d)?
experiments with whole blood, final concentration of streptokinase? 600 IU/ml.
for all coagulation activators used (see S2 Text). Sample clips of a video recording of the
fibrinolysis process for an experiment with blood plasma are presented in S2 Video.
Acoustic evaluation of the efficiency of fibrinolysis
The efficiency of fibrinolysis turned out to depend strongly on both the concentration of the
fibrinolytic agent and on the moment of its injection. The best lysis was observed when the
fibrinolytic agent was injected at the initial stage of the coagulation process (stage ?I? in Fig 2).
To investigate the dependence of the efficiency of fibrinolysis on the concentration of the
fibrinolytic drug, several series of experiments with identical drug injection timing were
performed. The drug was injected immediately after the acoustic registration of the coagulation
onset, as soon as the AMA exceeded the preset threshold level.
The curves showing AMA as a function of time for the experiments testing a series of
varying concentrations of urokinase are presented in Fig 4. It is evident that the smaller the dose of
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Fig 4. Curves of AMA (averaged modulus of amplitude of the acoustic signal) as a function of time for the experiments with
different concentrations of urokinase injected. (a,b,c,d)?sets of experiments with blood plasma; (e,f,g,h)?sets of experiments
with whole blood. The urokinase concentrations used were as follows: (a,e)?reference experiments, normal saline was injected
instead of a fibrinolytic drug; (b,f)? 200 IU/ml; (c,g)? 625 IU/ml; (d,h) ? 1250 IU/ml.
PLOS ONE | https://doi.org/10.1371/journal.pone.0211646
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fibrinolytic agent, the slower the dissolution of the fibrin clots. At urokinase concentrations of
50 IU/ml and lower, no fibrinolysis was observed during the 90-minute experimental period.
The time course of AMA changes in these experiments was practically identical to that
observed in the reference experiments, in which normal saline, instead of a fibrinolytic drug,
To qualitatively compare the efficiency of fibrinolysis in different experiments, we
introduced a special fibrinolysis efficiency index (FEI) (see ?Materials and methods?). The
dependences of FEI on the concentrations of the fibrinolytic agents used are presented in Fig 5. All
data presented in Fig 5 correspond to the experiments with an injection of a fibrinolytic agent
at the initial stage of the coagulation process. The sets of experimental points presented for
each drug were obtained in a series of experiments using blood plasma from the same donor
that was obtained on the same day.
Increase in fibrinolytic resistance of fibrin clots during their formation
The rate of dissolution of the fibrin aggregates in the experimental system substantially
depended on the time delay of fibrinolytic drug injection after the registration of coagulation
onset. When the fibrinolytic agent was injected at the initial stage of coagulation (stage ?I? in
Fig 2), the complete dissolution of all of the clots in the system occurred in the following 5?15
minutes. However, the same concentration of a fibrinolytic drug may fail to cause any
detectable lysis at all in cases where the injection was performed with a time delay of only several
minutes after the appearance of the primary microemboli in the flow.
The dependence of the efficiency of fibrinolysis on the time delay of the injection was
studied in detail with the aid of an automated drug injector. Several series of experiments were
carried out in which the same dose of fibrinolytic drug was injected with different time delays
after the registration of the appearance of first microemboli in the flow. The fibrinolytic
injection was conducted either immediately after the AMA value doubly exceeded its initial
background level or with a delay of 30, 60, 90, 120, 180 and 300 seconds.
The curves of AMA versus time for a series of experiments with different time delays of
drug injection are presented in Fig 6. Fig 7 shows the dependence of FEI on the delay time of
the fibrinolytic drug injection for 6 series of experiments with plasma samples of different
donors. It can be seen that a delay in the injection of more than 30 seconds after the
registration of the first microemboli leads to a significant decrease in the efficiency of fibrinolysis. In
cases where the injection delay was 5 minutes or more, practically no lysis was observed.
A similar effect was observed in the experiments with urokinase and tissue-type
plasminogen activator. An injection of a fibrinolytic drug during stage ?I? led to fast and effective
fibrinolysis, while at the beginning of stage ?II?, it led to far less pronounced lysis, and at the end of
stage ?II? or during stage ?III?, it caused practically no lysis at all. Thus, it can be concluded
that the fibrinolytic resistance of clots increases drastically during the first 5 minutes of their
Presently, ultrasonic methods are already used rather widely in the field of thrombosis and
hemostasis, for instance, in the diagnostics of deep vein thrombosis [
], the detection of
thrombi in the left atrial appendage  and the monitoring of intravascular emboli [
Taking into account the recent achievements in the development of implantable ultrasonic sensors
] it seems quite likely that, eventually, an ultrasonic technique for the monitoring of blood
coagulation and thrombi formation inside the human body will be created.
9 / 17
Fig 5. The dependences of FEI (fibrinolysis efficiency index) on the concentrations of the fibrinolytic agents used. The data for streptokinase are marked by black
squares; the data for urokinase, by white diamonds; and the data for tissue-type plasminogen activator, by gray triangles. The concentrations for streptokinase and
urokinase are indicated in IU/ml at the lower scalebar of the plot; the concentrations of t-PA are indicated in mg/ml at the upper scalebar of the plot.
In our previous works, we have shown the applicability of ultrasonic methods for the
noninvasive registration of coagulation processes occurring under intensive blood flow conditions
10 / 17
Fig 6. Curves of AMA versus time for an experimental series with different time delays of drug injection. a?
control experiment with no fibrinolytic drug injected; b?injection delay of 300 seconds; c?injection delay of 60
seconds; d?injection no delay. A concentration of streptokinase was 250 IU/ml.
]. Further development of these methods seems to be very promising because they may
enable coagulation monitoring in the areas of the vascular system where thrombus formation
poses the greatest threat to the patient?s life and health, specifically, the large vessels of heart
In the present study, it has been shown that ultrasonic methods enable the registration of
coagulation processes at the stage when timely pharmacological intervention can still prevent
the formation of macroscopic clots in the experimental system. Thus, it was shown that
realtime ultrasonic registration of coagulation processes, in principle, provides the facility to
control thrombi formation.
Fig 7. The dependence of FEI on the delay time of the fibrinolytic drug injection. The dependence was established
on the basis of 6 series of experiments with blood plasma from different donors. The concentration of streptokinase
injected was constant in all the experiments and was equal to 250 IU/ml.
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The results presented in this paper may open prospects for creating portable or even
implantable devices, which would be somewhat similar to insulin pumps currently used in
clinical practice [
]. By means of ultrasound, such a device could provide not only the
monitoring of blood clotting and fibrinolysis, but also active control of these processes. The
miniature portable injector with several Doppler sensors on critical human arteries could timely
inject fibrinolytics directly at the early stage of clotting when hemostasis could be corrected
faster and more efficiently.
In our experiments the resistance of clots to fibrinolysis increased drastically in the first few
minutes of clots formation. The increase in the resistance of clots to the action of fibrinolytic
agents with time is well known in clinical practice [
]. Although our results show a similar
trend to that of clinical observations, the time period within which the clots remained sensitive
to the action of fibrinolytic agents turned out to be at least ten fold shorter in our experiments.
The particular mechanisms underlying such a rapid increase in the fibrinolytic resistance of
the clots are still unclear. However, it may be assumed that the effect observed in our work is
the result of chemical stabilization of the clots on one hand [
], and on the other hand,
changes in the structure of the clots, leading to a decrease in the permeation of fibrinolysis
activators to the inner areas of the clots [
Concerning chemical stabilization of fibrin clots it is generally known that the action of
coagulation factor XIII [
] and thrombin activatable fibrinolysis inhibitor (TAFI) [
substantially increase the fibrinolytic resistance of forming clots. Both of the factors are converted
to their active forms by thrombin. Activated factor XIII restrain fibrinolysis by covalent linking
of ?2-antiplasmin to fibrin [
] as well as by cross-linking of ?- and/or ?-chains of fibrin [
Activated TAFI down-regulates fibrinolysis by removal of C-terminal lysines from fibrin,
preventing in that way binding and activation of plasminogen [
Moreover it is worth to mention that blood flow itself can influence fibrinolytic resistance
of forming clots in a bidirectional manner. On one hand flow influences the structure of the
fibrin network [
], making it more dense and less permeable to lytic agents, thus
impeding the fibrinolytic process . On the other hand, the flow substantially influences the
character of the mass transfer inside the clot and near its surface, thus accelerating the fibrinolytic
dissolution of the clots [
Keeping this in mind, within the present work, it was essential to create the experimental
conditions of flow to mimic thrombi formation taking place in large arteries. The experimental
scheme chosen for this purpose is in a way, analogous to the well-known Chandler system
], which is widely used up to date to create artificial clots mimicking arterial thrombi [
]. Despite some differences in the setups, the development of coagulation processes in our
experimental system was, in many aspects, similar to that observed in a classical Chandler
system. For instance, the stage of multiple microemboli formation in the flow, resembling a
?snow-storm?, which was observed in our experiments, was previously described for the
Chandler system in experiments by McNicol et al .
Of course no in vitro experimental system could completely reproduce in vivo formation of
arterial thrombi. Certainly, further in vivo investigations are required to answer a general
question: whether the monitoring of the early stages of blood coagulation can increase the real
clinical facilities for the prevention of thrombotic complications. Until recently, practically all
research on the ultrasonic registration of blood coagulation has been carried out with in vitro
model systems [
7?18, 23?25, 53
]. A few novel studies in this research field that have employed
in vivo experiments have been published just recently [
]. The small number of such
works may be attributed to the necessity of the convergence of several branches of modern
science to carry out this type of research. We hope that the present work will attract additional
13 / 17
interest and attention among researchers to further address the problems of ultrasonic
monitoring of blood coagulation in vivo.
S1 Text. Interpretation of acoustic signals reflected by plasma and whole blood.
S2 Text. Registration of coagulation onset initiated by different types of activators.
S1 Video. Coagulation under intensive flow conditions registered optically and
S2 Video. Dissolution of fibrin clots induced by fibrinolytic drug injection.
S1 Fig. Frames from S1 Video. Acoustic channel is marked by blue frame. Optical channel is
marked by red frame. Four successive characteristic stages of the coagulation process are
presented as: (A)?lag phase, (B)??snow-storm? phase, (C)?clots aggregation phase,
S2 Fig. Frames from S2 Video. Acoustic channel is marked by blue frame. Optical channel is
marked by red frame. Successive characteristic stages of the fibrinolysis process are presented
as: (A)?large fibrin clot, (B)?partially lysed clot fragments, (C)?final stage of clot dissolution.
S3 Fig. AMA curves for experiments with whole blood (a) and blood plasma (b) plotted in the
same scale. Both curves are normalized on the initial signal level observed in the experiment
with blood plasma.
S4 Fig. Curves of AMA (averaged modulus of amplitude of the acoustic signal) for the
experiments with different coagulation activators used. (a, d)? 50 ?l of 1% kaolin
suspension; (b, e)? 600 ?l of 10% calcium chloride solution; (c, f)? 50 ?l of thromboplastin solution,
diluted by 12 times with normal saline; (a, b, c)?experiments with no fibrinolytic agent
injected; (d, e, f)?experiments with 1250 IU/ml urokinase injected. All experiments were
performed with plasma of the same donor collected at the same day.
Conceptualization: Konstantin G. Guria, Georgy Th. Guria.
Data curation: Dmitry A. Ivlev, Shakhla N. Shirinli, Svetlana G. Uzlova.
Formal analysis: Dmitry A. Ivlev, Shakhla N. Shirinli, Konstantin G. Guria, Svetlana G.
Uzlova, Georgy Th. Guria.
Funding acquisition: Georgy Th. Guria.
Investigation: Dmitry A. Ivlev, Shakhla N. Shirinli, Konstantin G. Guria, Svetlana G. Uzlova.
Methodology: Dmitry A. Ivlev, Shakhla N. Shirinli, Konstantin G. Guria, Svetlana G. Uzlova.
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Project administration: Konstantin G. Guria.
Resources: Konstantin G. Guria.
Software: Dmitry A. Ivlev.
Supervision: Georgy Th. Guria.
Validation: Dmitry A. Ivlev, Shakhla N. Shirinli, Konstantin G. Guria, Svetlana G. Uzlova.
Visualization: Dmitry A. Ivlev, Shakhla N. Shirinli.
Writing ? original draft: Konstantin G. Guria, Georgy Th. Guria.
Writing ? review & editing: Konstantin G. Guria, Georgy Th. Guria.
15 / 17
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