Dissolution Of Blood Clots Research Articles

Comparative Study of Frequency of Alveolar Osteitis, with and without using Platelet-Rich Fibrin in Mandibular Third Molar Surgery.

Alveolar ostitis (AO) is the dissolution of blood clot due to enhanced local fibrinolysis and is caused by trauma to the jaw (direct) or because of bacterial involvement (indirect), which result in the activation of plasminogen pathway. Platelet-rich fibrin (PRF) is a platelet concentrate that comprises numerous autologous growth factors, and immune cells hence has the potential to expedite the healing process. The objective of the study was to determine the efficacy of PRF in the surgically extracted third molar in the context of its potential progress to AO. A total of 180 patients of 18-65 years with unilateral painful mandibular third molars due to caries, failed endodontics treatment, and pericoronitis were included in the study. Exclusion criteria were patients who were medically compromised, smokers, alcoholic, poor oral hygiene, third molar having associated periapical pathology, and receiving antibiotic regime in the last 2 weeks. Before starting surgical procedure, patients were randomly divided into two groups using lottery method. Group I received PRF in the extraction socket, while in Group II, the extraction site was left for normal healing as practiced in a standard procedure. Pain was assessed in terms of pain score, and it was recorded on a 10 mm visual analog scale on the first and third postoperative days. Mean age of the patients was 41.35 ± 9.87 years. The mean age in Group I was 42.84 ± 10.52 years, and in Group II, it was 40.54 ± 9.52 years. Out of 180 patients, 90 (50.0%) were male and 90 (50.0%) were female, with a male-to-female ratio of 1 : 1. Frequency of AO following mandibular third molar surgery in Group I receiving PRF was 2.22% and in non-PRF group 12.22% (p-value = 0.010). The incidence of AO following mandibular third molar surgery was lower when PRF was used.

The Acute and Chronic Effects of Resistance and Aerobic Exercise in Hemostatic Balance: A Brief Review

Hemostatic balance refers to the dynamic balance between blood clot formation (coagulation), blood clot dissolution (fibrinolysis), anticoagulation, and innate immunity. Although regular habitual exercise may lower the incidence of cardiovascular diseases (CVD) by improving an individual's hemostatic profile at rest and during exertion, vigorous exercise may increase the risk of sudden cardiac death and venous thromboembolism (VTE). This literature review aims to investigate the hemostatic system's acute and chronic adaptive responses to different types of exercise in healthy and patient populations. Compared to athletes, sedentary healthy individuals demonstrate similar post-exercise responses in platelet function and coagulatory and fibrinolytic potential. However, hemostatic adaptations of patients with chronic diseases in regular training is a promising field. Despite the increased risk of thrombotic events during an acute bout of vigorous exercise, regular exposure to high-intensity exercise might desensitize exercise-induced platelet aggregation, moderate coagulatory parameters, and up-regulate fibrinolytic potential via increasing tissue plasminogen activator (tPA) and decreasing plasminogen activator inhibitor (PAI-1) response. Future research might focus on combining different types of exercise, manipulating each training characteristic (frequency, intensity, time, and volume), or investigating the minimal exercise dosage required to maintain hemostatic balance, especially in patients with various health conditions.

Correlations between the Changing Levels of Tissue Plasminogen Activator and Adiposity Following Exercise-Induced Weight Loss.

Cardiovascular disease is a major threat to global public health. Tissue plasminogen activator (TPA) is a serine protease that dissolves blood clots, which can also lead to excessive bleeding. Fibrinogen (FIBR), a glycoprotein, is converted by thrombin to fibrin and then to a fibrin-based blood clot. Both TPA and FIBR levels in the blood are associated with an increased risk of coronary heart disease, and the levels of the two factors are also positively correlated with total adipose tissue amounts. Visceral and subcutaneous adipose tissues (VAT and SAT) can contribute differently to whole-body metabolism. In this study, we sought to assess: (1) the strength of the correlation between the changing levels of the two factors and the changing amounts of VAT/SAT during exercise-induced weight loss, (2) whether there is any difference between the two types of adipose tissues in terms of the correlation, and (3) which factor, TPA or FIBR, is more sensitive to changes in adiposity? For this study, we analyzed the data from the diabetes prevention program (DPP), in which the participants were divided into three groups, with one group undergoing a lifestyle change that involved maintaining a minimum of 7% weight loss with physical activity. We found that the basal amounts of VAT and SAT were correlated with TPA and FIBR levels. However, following weight loss, adiposity changes were strongly correlated with the changing levels of TPA, but not FIBR, for both men and women. Therefore, TPA, but not FIBR, is sensitive to changes in adiposity. Furthermore, regarding TPA, weight loss sensitized its correlation with SAT, but not VAT. This study shows how adipose tissues distinctively affect TPA and FIBR levels, two factors associated with cardiovascular disease and ischemic stroke.

Simultaneous purification and characterization of detergent-stable, solvent-tolerant haloextremozymes protease and lipase from Haloferax sp. strain GUBF 2.

Industrial important proteases and lipases are in increasing demand for various biotechnological applications. In the present study, the concomitantly produced protease and lipase by Haloferax sp. strain GUBF 2 were simultaneously purified as a heterogeneous lipase (45 and 66kDa) and homogeneous protease (180kDa); with 28.3 and 31.36 fold purity, respectively using Sephadex G-200. The aforementioned extremozymes were active at pH 3-13, 20-80°C, 1-5M NaCl, with optimal activity at pH 6, 70°C, and 3M NaCl, thus exhibiting attributes of true haloextremozymes. The Km and Vmax of purified lipase were 3.47mM and 16.2U/mL, while protease were 3.29mg/mL and 28.5U/mL, respectively. FTIR bands corresponding to the vibrations of amide II and amide III were detected in haloextremozymes which could perhaps be used to determine the secondary structure of the purified proteins. Furthermore, the activity of both enzymes was stimulated by Ca2+ and inhibited by 10mM Hg2+ and phenylmethyl sulphonyl fluoride (PMSF). Additionally, these haloextremozymes are stable in the presence of detergent additives and organic solvents. In addition, purified protease displayed 74.3 ± 4.85% in-vitro blood clot dissolution activity. Conclusively this study revealed the key features, unusual properties, and possible biomedical applications of detergent-stable and organic solvent-tolerant haloextremozymes from Haloferax sp. strain GUBF 2 to date unexplored.

Gene variants in pro-coagulant and anti-coagulant genes could be prognostic genetic markers of COVID-19 susceptibility

BackgroundPresent study aimed to identify DNA polymorphisms (variants) which can modulate the risk of COVID-19 infection progression to severe condition. TaqMan based SNP genotyping assay was performed for 11 single nucleotide polymorphisms (SNPs) in pro-coagulant and anti-coagulant genes. MethodologyA total of 33 COVID-19 patients, including dead, severe and moderately infected individuals were compared to 35 healthy controls. Both alleles in the SNP were labelled with two different fluorescent dyes (FAM and VIC) during assay formulation. DNA of study subjects were mixed with SNP assay and TaqMan master mix on 96 well PCR plate according to manufacturer’s protocol and RT-PCR was performed. Allelic discrimination assay gave clear results for presence of specific allele in each sample. Three SNPs were located in the pro-coagulant genes, another three involved in blood clot dissolution while rest five were in the genes encoding natural anti-coagulants. COVID-19 infected patients were further sub-divided into three groups, deceased (n = 16), severe (n = 10) and moderately infected (n = 7). ResultsSNP genotyping showed significant differences between COVID-19 patients and controls in two SNPs, rs6133 in Selectin-P (SELP) and rs5361 in Selectin-E (SELE) gene. Also, rs2020921 and rs8176592, in clot dissolution genes, tissue Plasminogen activator (tPA) and tissue factor pathway inhibitor (TFPI) respectively showed significant genotypic and allelic difference in patients of COVID-19 compared to healthy controls. Further three SNPs rs2227589, rs757583846, and rs121918476 in natural anti-coagulant genes anti-thrombin III (ATIII), protein C (PROC), and protein S (PROS) respectively showed statistically significant difference between the study groups. ConclusionOur findings indicate that gene variants, those involved in coagulation and anti-coagulation may play a major role in determining individual susceptibility to COVID-19.

S3516 A Case of Recurrent Thromboangiitis Obliterans (Buerger's Disease) in a Patient With Abdominal Pain and Intestinal Transplant

Introduction: We describe a case of abdominal pain and recurrent disease following intestinal transplant in a patient with a history of mesenteric ischemia and Thromboangiitis obliterans (Buerger's syndrome) that did not resolve with standard medical therapy. Case Description/Methods: A wonderful 44 year old female presents with intestinal infarction. The patient required three prior revascularization procedures with acute on chronic mesenteric ischemia with superior mesenteric artery thrombosis. She was taken to the operating room for necrotic small bowel with resection 20 centimeters distal to the ligament of treitz and placed on parenteral nutrition. Following recurrent episodes of line related bacteremia and fungemia she was listed for intestinal transplantation. After being off tobacco for a year she received and small bowel and right colon transplant. She had initial anticoagulation which was restarted four year later after a deep venous thrombosis to the lower extremity. Seven years following transplant the patient had inconsistent use of the anticoagulation along with recurrent tobacco abuse and developed recurrent mesenteric ischemia with acute on chronic occlusion of the celiac trunk, superior mesenteric artery, and inferior abdominal aorta leading to generalized abdominal pain, ischemic colitis and septic shock. Given recurrent abdominal infections patient had enterectomy 8 years and six months following intestinal transplantation. The patient subsequently developed bacteremia, candidemia and line related thrombosis. Patient had eventual transition to palliative management and died. Discussion: Buerger's disease (also known as thromboangiitis obliterans) affects blood vessels in the body, most commonly in the arms and legs. The use of tobacco is essential for both the initiation and progression of this disease. Blood vessels swell, which can prevent blood flow, causing clots to form. This can lead to pain, tissue damage, and even gangrene. It is typically treated with medications that dilate blood vessels, improve blood flow or dissolve blood clots, such as anticoagulants. Ongoing tobacco cessation is vital to success following rare intestinal transplantation. We present a case of intestinal transplant for Buerger’s Disease with recurrent thrombosis seven years following intestinal transplant attributed to recurrent tobacco abuse.

In Vitro Blood Clot Formation and Dissolution for Testing New Stroke-Treatment Devices.

Strokes are among the leading causes of death worldwide. Ischemic stroke, due to plaque or other buildup blocking blood flow to the brain, is the most common type. Although ischemic stroke is treatable, current methods have severe shortcomings with high mortality rates. Clot retrieval devices, for example, can result in physically damaged vessels and death. This study aims to create blood clots that are representative of those found in vivo and demonstrate a new method of removing them. Static blood clots were formed using a 9:1 ratio of whole sheep blood and 2.45% calcium chloride solution. This mixture was heated in a water bath at 37 °C for approximately one hour until solidified. Following clot solidification, human plasmin was introduced by various methods, including soaking, injection, and membrane perfusion, and the resulting dissolution percentages were determined. Different clot types, representative of the wide range found physiologically, were also manufactured and their dissolution characteristics evaluated. A method to reproducibly create blood clots, characteristic of those found in vivo, is essential for the production of stroke retrieval devices that can efficiently and effectively remove clots from patients with low mortality rates and little/no damage to the surrounding vessels.

Improving treatment for acute ischemic stroke-Clot busting innovation in the pipeline.

Acute ischemic stroke is a consequence of disrupted blood flow to the brain, caused by thrombosis—the pathological formation of occlusive clots within blood vessels, which can embolize distally to downstream tissues and microvasculature. The highest priority of stroke treatment is the rapid removal of occlusive clots and restoration of tissue perfusion. Intravenous thrombolysis is the pharmacological standard-of-care for the dissolution of blood clots, wherein thrombolytic drugs are administered to restore vessel patency. While the introduction of recombinant tissue-plasminogen activator (rtPA) in 1996 demonstrated the benefit of acute thrombolysis for clot removal, this was countered by severe limitations in terms of patient eligibility, lytic efficacy, rethrombosis and safety implications. Development of safer and efficacious treatment strategies to improve clot lysis has not significantly progressed over many decades, due to the challenge of maintaining the necessary efficacy-safety balance for these therapies. As such, rtPA has remained the sole approved acute therapeutic for ischemic stroke for over 25 years. Attempts to improve thrombolysis with coadministration of adjunct antithrombotics has demonstrated benefit in coronary vessels, but remain contraindicated for stroke, given all currently approved antithrombotics adversely impact hemostasis, causing bleeding. This Perspective provides a brief history of stroke drug development, as well as an overview of several groups of emerging drugs which have the potential to improve thrombolytic strategies in the future. These include inhibitors of the platelet receptor glycoprotein VI and the signaling enzyme PI3-Kinase, novel anticoagulants derived from hematophagous creatures, and proteolysis-targeting chimeras.

Performance of a Helical Microswimmer Traversing a Discrete Viscoelastic Network with Dynamic Remodeling

Microorganisms often navigate a complex environment composed of a viscous fluid with suspended microstructures such as elastic polymers and filamentous networks. These microstructures can have similar length scales to the microorganisms, leading to complex swimming dynamics. Some microorganisms secrete enzymes that dynamically change the elastic properties of the viscoelastic networks through which they move. In addition to biological organisms, microrobots have been engineered with the goals of mucin gel penetration or dissolving blood clots. In order to gain insight into the coupling between swimming performance and network remodeling, we used a regularized Stokeslet boundary element method to compute the motion of a microswimmer consisting of a rotating spherical body and counter-rotating helical flagellum. The viscoelastic network is represented by a network of points connected by virtual elastic linkages immersed in a viscous fluid. Here, we model the enzymatic dissolution of the network by bacteria or microrobots by dynamically breaking elastic linkages when the cell body of the swimmer falls within a given distance from the link. We investigate the swimming performance of the microbes as they penetrate and move through networks of different material properties, and also examine the effect of network remodeling.

Transcranial ultrasound stimulation applied in ischemic stroke rehabilitation: A review.

Ischemic stroke is a serious medical condition that is caused by cerebral vascular occlusion and leads to neurological dysfunction. After stroke, patients suffer from long-term sensory, motor and cognitive impairment. Non-invasive neuromodulation technology has been widely studied in the field of stroke rehabilitation. Transcranial ultrasound stimulation (TUS), as a safe and non-invasive technique with deep penetration ability and a tiny focus, is an emerging technology. It can produce mechanical and thermal effects by delivering sound waves to brain tissue that can induce the production of neurotrophic factors (NFs) in the brain, and reduce cell apoptosis and the inflammatory response. TUS, which involves application of an acoustic wave, can also dissolve blood clots and be used to deliver therapeutic drugs to the ischemic region. TUS has great potential in the treatment of ischemic stroke. Future advancements in imaging and parameter optimization will improve the safety and efficacy of this technology in the treatment of ischemic stroke.

NATTOKINASE: ARMOUR AGAINST THROMBOSIS

In this review paper, an emphasis is made to focus on the history, source, structure, mode of action, and application of Nattokinase. The review reveals that Nattokinase can act as a potent thrombolytic agent as compared to other agents which are commercially available. Studies on NK as a thrombolytic agent have also be proved it as an useful for dissolving blood clots by converting plasminogen to plasmin, which further act on fibrin clots. Nattokinase is been isolated from Bacillus subtilis varnatto. Various studies been done on the application of NK has shown to overcome the undesirable effects caused by other tissue plasminogen activator, Streptokinase, Staphylokinaseetc and increased its area of application.

Acute cholangitis due to haemobilia complicating percutaneous cholecystostomy: First literature case report.

BackgroundLaparoscopic cholecystectomy is the standard treatment for acute cholecystitis. Cholecystostomy is a good option in patients with significant comorbidities. We report a case of a patient having had a percutaneous cholecystostomy for acute cholecystitis complicated with haemobilia and acute cholangitis.Presentation of a caseA woman aged 64 years old, with a history of diabetes, arterial hypertension, and chronic obstructive pulmonary disease was admitted to our institution with acute cholecystitis.We opted for transhepatic percutaneous cholecystostomy (PC) and antibiotics.On the fourth day, the patient had acute cholangitis due to haemobilia.We injected physiologic saline serum through the drain of cholecystostomy to dissolve the blood clot. There was a clinical improvement.We performed laparoscopic cholecystectomy two months later. The patient had an uneventful recovery with a follow-up of five months.DiscussionWe report the first literature report of acute cholangitis due to haemobilia complicating percutaneous cholecystostomy in a patient admitted for cholecystitis.We highlight the importance of the injection of saline physiologic serum from the catheter. Medical treatment with antibiotics may be enough knowing that blood clots can disappear spontaneously. In case of failure, ERCP with sphincterotomy should be performed.ConclusionHaemobilia causing acute cholangitis is a rare complication of percutaneous cholecystostomy. Conservative treatment with antibiotics and injection of saline physiologic serum from the catheter is a good treatment option. In case of failure, ERCP should not be delayed.

MO266: Deficiency of Urokinase-Type Plasminogen Activator Exacerbates CBSA-Induced Membranous Nephropathy in Mice

Abstract BACKGROUND AND AIMS In nondiabetic population, primary membranous nephropathy (PMN) is the most common cause of idiopathic nephrotic syndrome in the world. Urokinase-type plasminogen activator (uPA) is one of the key members of fibrinolysis system, which functions as dissolving blood clots to prevent obstruction of blood vessels. Currently, the roles of uPA in PMN remain undefined. METHOD Six-week-old male mice with Plau wild-type and knockout in BALB/c strain were used to induce MN by cationic bovine serum albumin (cBSA). Biochemistry assays of blood and urine were measured by a Fuji Dri-Chem FDC NX 500 machine. Glomerular polyanions were determined by using Colloidal Iron Stain Kit. Reactive oxygen species (ROS) was detected by immunohistochemistry stained by 4-HNE antibody. TUNEL positivity in the kidneys of mice was determined using an ApopTag® Plus Peroxidase In Situ Apoptosis Kit. The deposition of immune complex in glomeruli was examined by a transmission electron microscope. Lymphocyte subsets were determined by flow cytometry. Serum concentrations of IgG1 and IgG2a were measured by ELISA. RESULTS It has been reported that BALB/c mice is an ideal strain for mimicking human PMN. Thus, we generated uPA deficient mice (Plau-/-) in BALB/c strain by backcrossing C.129S2-Plautm1Mlg/J mice with BALB/c wild-type mice to N10. Plau-/- mice exhibited severe urinary albumin-to-creatinine ratio significantly when compared with wild-type mice at 2 weeks post-cBSA administration. Consistently, cBSA-induced Plau-/- mice displayed higher serum creatinine, hypoalbuminemia and hypercholesterolemia than wild-type mice. Histologically, Plau-/- mice presented more severed glomerular basement thickening, IgG granular deposition, intensified podocyte effacement, irregular thickening of glomerular basement membrane and subepithelial deposits than wild-type mice. Attenuated colloidal iron stain was observed in Plau-/- mice when compared with wild-type mice. Moreover, elevated ROS and apoptosis in the kidneys of Plau-/- mice were observed. B lymphocyte subsets were enriched significantly in the Plau-/- mice with MN, suggesting that pathological aggravation of MN is associated with dominant B lymphocyte population. The enriched ratio of IgG1 to IgG2a further confirmed predominant Th2 subset in Plau-/- mice. CONCLUSION uPA deficiency enhances Th2 dominant immune response, leading to enhancement of ROS and apoptosis in the kidneys, which subsequently exacerbates the progression of MN. Maintenance of uPA homeostasis may be a promising therapeutic approach for MN management.

Potential effects and relevant lead compounds of Vigna mungo (L.) Hepper seeds against bacterial infection, helminthiasis, thrombosis and neuropharmacological disorders

Multidrug-resistant bacterial infections, helminthiasis, thrombosis, anxiety and insomnia are some of the major global health concerns. Vigna mungo (L.) Hepper (VM) has been used traditionally to treat microbial infection, helminthic disorder, schizophrenia, memory loss, and blood circulatory problem. This research aims to discover antibacterial, anthelmintic, thrombolytic and neuropharmacological effects of the methanol extract of Vigna mungo seeds (MESVM), and also in-silico prediction of relevant lead compounds by molecular docking and ADME/T analysis. The crude extracts and subsequent fractions of MESVM were investigated for antibacterial activity by disc diffusion method, anthelmintic activity by paralysis and death test on earthworms, and thrombolytic activity by in vitro blood clot dissolution test. Open-field test and elevated plus maze test were performed for evaluating anxiolytic activity of the extracts. Using molecular docking, ligand poses of selected VM seeds’ phytoconstituents were predicted targeting tubulin, GlcN-6-P synthase, and human tissue plasminogen activator proteins for anthelmintic, antibacterial, and thrombolytic activity, respectively. In the antibacterial activity test, the MESVM at 10000 μg/mL concentration created highest and significant (P < 0.001) zone of inhibition against Staphylococcus aureus (15.42 mm) and Escherichia coli (12 mm) compared with tetracycline. The MESVM exhibited remarkable anthelmintic activity at 50 mg/mL concentration with 35.4 min paralysis time, 75.2 min death time and were closer to the durations of standard drug albendazole. No test extract showed anxiolytic activity. In thrombolytic activity test, all concentrations of MESVM produced clot lytic activity with high significance (P < 0.001) in comparison with the blank. In docking, 2′-hydroxygenistein, cyclokievitone hydrate, and aureol displayed maximum affinity to the target proteins for anthelmintic, antibacterial, and thrombolytic activity, respectively. This research revealed that the MESVM demonstrated potential anthelmintic, antibacterial and thrombolytic effects that confirmed the folkloric uses of VM and the found relevant lead compounds might be further optimized in future drug development.

Dissolution Effect of Alteplase on Arterial Blood Clot Model of Hypertensive Intracerebral Hemorrhage Patients in vitro.

ObjectiveTo explore the dissolution effect of alteplase (rt-PA) on arterial blood clots of patients with hypertensive cerebral hemorrhage in vitro and analyze the optimal concentration and action time of rt-PA for intracranial hematomas.MethodsThe arterial blood of 35 patients with confirmed hypertensive cerebral hemorrhage were collected, centrifuged, and the serum was aspirated to prepare the blood clot model. The 0.125, 0.25, 0.5, 1, 2, and 3 mg t-PA, 20,000 U, and 40,000 U urokinase (u-PA) were taken for the corresponding blood clot for dissolution test. The blood clot volume and dissolution volume was measured at 0, 30, 60, 90, 120, and 150 min.ResultsWithout intervention, the blood clot volume of men was higher than that of women at 0, 30, 60, and 90 min (P < 0.05). Without intervention, hematocrit (HCT) was correlated with blood clot volume and the correlation decreased with time. The 30, 60, and 90 min dissolution curves of each group showed an upward trend (P < 0.05), and the dissolution curves tended to be flat at 120 min and 150 min. The dissolution volume of.125 mg/3 ml, 0.25 mg/3 ml, 0.5 mg/3 ml rt-PA, 20,000 U, 40,000 U u-PA was higher than that of 1, 2, 3 mg/ml rt-PA (P < 0.05). The dissolution volume of.125 mg/3 ml, 0.25 mg/3 ml, 0.5 mg/3 ml rt-PA was not significantly different from 20,000 and 40,000 U u-PA (P > 0.05). Gender differences did not affect the effects of the above drugs.ConclusionIn vitro, low-concentration rt-PA has a better dissolution effect, and it shows a time-dependent effect, reaching the highest effect in 90 min.

Zinc(II) Induced Neurological Thrombolytic Activities for COVID-19 Thrombus Prevention, Inflammation, Fibrin Degradation, Fibrinolysis of Dissolving Blood Clots and Blood Flow Reperfusion after Thrombolysis

Zinc(II) Induced Neurological Thrombolytic Activities for COVID-19 Thrombus Prevention, Inflammation, Fibrin Degradation, Fibrinolysis of Dissolving Blood Clots and Blood Flow Reperfusion after Thrombolysis

Research Progress of Nattokinase Quality and Safety Evaluation

Nattokinase is a serine protease produced by Bacillus natto in the process of fermenting natto. It has physiological functions such as dissolving blood clots. This article briefly summarizes the thrombolytic function and mechanism of nattokinase, focusing on the research progress of nattokinase activity determination methods and other quality indicators and safety evaluation. The research direction of nattokinase product development and quality and safety is prospected, in order to provide a theoretical basis for the standardization of natto and its products (including nattokinase products).

Reteplase Fc-fusions produced in N. benthamiana are able to dissolve blood clots ex vivo.

Thrombolytic and fibrinolytic therapies are effective treatments to dissolve blood clots in stroke therapy. Thrombolytic drugs activate plasminogen to its cleaved form plasmin, a proteolytic enzyme that breaks the crosslinks between fibrin molecules. The FDA-approved human tissue plasminogen activator Reteplase (rPA) is a non-glycosylated protein produced in E. coli. rPA is a deletion mutant of the wild-type Alteplase that benefits from an extended plasma half-life, reduced fibrin specificity and the ability to better penetrate into blood clots. Different methods have been proposed to improve the production of rPA. Here we show for the first time the transient expression in Nicotiana benthamiana of rPA fused to the immunoglobulin fragment crystallizable (Fc) domain on an IgG1, a strategy commonly used to improve the stability of therapeutic proteins. Despite our success on the expression and purification of dimeric rPA-Fc fusions, protein instability results in high amounts of Fc-derived degradation products. We hypothesize that the "Y"- shape of dimeric Fc fusions cause steric hindrance between protein domains and leads to physical instability. Indeed, mutations of critical residues in the Fc dimerization interface allowed the expression of fully stable rPA monomeric Fc-fusions. The ability of rPA-Fc to convert plasminogen into plasmin was demonstrated by plasminogen zymography and clot lysis assay shows that rPA-Fc is able to dissolve blood clots ex vivo. Finally, we addressed concerns with the plant-specific glycosylation by modulating rPA-Fc glycosylation towards serum-like structures including α2,6-sialylated and α1,6-core fucosylated N-glycans completely devoid of plant core fucose and xylose residues.

Current state of treatment for lower extremity acute deep venous thrombosis (a literature review)

Despite the use of modern methods of diagnosis and treatment, deep vein thrombosis (DVT) of the lower extremities remains a fairly common disease. In half of all cases, DVT may be asymptomatic and manifest itself in subsequent symptoms of pulmonary embolism (PE) or postthrombotic syndrome (PTS). An important role in the pathogenesis of this disease is played by a variety of factors and conditions that contribute to thrombosis in the venous vessels of the lower extremities, as well as impaired venous outflow from the lower extremity due to blockage of the venous lumen by such a thrombus. The action of various treatments is aimed at certain links in the pathogenesis, namely: anticoagulant therapy prevents further thrombosis, thrombolysis dissolves blood clots, surgical and mechanical thrombectomy remove blood clots from the lumen of the vein, lysis or removal of thrombotic masses restores thrombosis in the small circle of blood circulation. There is no single, universal method for combating DVT. In addition, there are new methods, such as the use of devices for pharmaco-mechanical thrombolysis, stent-retrievers which need to be tested for effectiveness and safety, as well as for a comparative analysis with existing treatments. Given the severe consequences of DVT that include early mortality, recurrence and complications of the disease, and can be associated with death, rehospitalization, deterioration in patient quality of life and disability, the choice and application of certain treatments or combinations thereof becomes important. Equally important are the issues of primary and secondary prevention of DVT, which reduce the above-mentioned risks and should be pursued in each patient. The aim. To study the world experience in the treatment of DVT, to summarize modern approaches to the treatment of patients with DVT based on the principles of evidence-based medicine by reviewing and analyzing modern scientific literary sources in scientometric bases. Materials and methods. We searched for publications in scientometric databases including Pub Med, Google Scholar, Web of Sciense, Scopus by keywords, as well as for the latest recommendations and guidelines that cover modern methods of diagnosis and treatment of DVT of the lower extremities. Articles, systematic reviews and literature relevant to the research topic were reviewed and analyzed. The inclusion criteria were: articles and studies describing to the pathophysiology, diagnosis and treatment of DVT, studies with the longest observation, recommendations and guidelines of professional associations regarding DVT. The exclusion criteria were: articles not related to the research topic, a small number of patients included in the study (less than 15 people). Conclusions. DVT and its complications can lead to fatal conditions, such as pulmonary embolism, and often adversely affect patients’ quality of life. DVT is potentially life-threatening and should be considered by a physician and patient as a life-threatening disease. Anticoagulant therapy is the main option for both DVT treatment and secondary prevention of venous thromboembolism and PTS recurrence. Some patients may receive drug therapy on an outpatient basis. Other patients with severe disease and complications need inpatient management. An open surgery, percutaneous endovascular procedures and various combinations thereof with the addition of anticoagulant therapy could be applied to this group. The lack of clear criteria for selecting patients and indications for endovascular interventions and surgical thrombectomy requires further research in this area.

Thrombolytic Enzymes of Microbial Origin: A Review.

Enzyme therapies are attracting significant attention as thrombolytic drugs during the current scenario owing to their great affinity, specificity, catalytic activity, and stability. Among various sources, the application of microbial-derived thrombolytic and fibrinolytic enzymes to prevent and treat vascular occlusion is promising due to their advantageous cost–benefit ratio and large-scale production. Thrombotic complications such as stroke, myocardial infarction, pulmonary embolism, deep venous thrombosis, and peripheral occlusive diseases resulting from blood vessel blockage are the major cause of poor prognosis and mortality. Given the ability of microbial thrombolytic enzymes to dissolve blood clots and prevent any adverse effects, their use as a potential thrombolytic therapy has attracted great interest. A better understanding of the hemostasis and fibrinolytic system may aid in improving the efficacy and safety of this treatment approach over classical thrombolytic agents. Here, we concisely discuss the physiological mechanism of thrombus formation, thrombo-, and fibrinolysis, thrombolytic and fibrinolytic agents isolated from bacteria, fungi, and algae along with their mode of action and the potential application of microbial enzymes in thrombosis therapy.