The Anticoagulant and Nonanticoagulant Properties of Heparin

Quality control, safety assessment and preparation approaches of low molecular weight heparin

Low Molecular Weight Heparins (LMWHs) are well-established for use in the prevention and treatment of thrombotic diseases, and as a substitute for unfractionated heparin (UFH) due to their predictable pharmacokinetics and subcutaneous bioavailability. LMWHs are produced by various depolymerization methods from UFH, resulting in heterogeneous compounds with similar biochemical and pharmacological properties. However, the delicate supply chain of UFH and potential contamination from animal sources require new manufacturing approaches for LMWHs. Various LMWH preparation methods are emerging, such as chemical synthesis, enzymatic or chemical depolymerization and chemoenzymatic synthesis. To establish the sameness of active ingredients in both innovator and generic LMWH products, the Food and Drug Administration has implemented a stringent scientific method of equivalence based on physicochemical properties, heparin source material and depolymerization techniques, disaccharide composition and oligosaccharide mapping, biological and biochemical properties, and in vivo pharmacodynamic profiles. In this review, we discuss currently available LMWHs, potential manufacturing methods, and recent progress for manufacturing quality control of these LMWHs.

Improving hemocompatibility in tissue-engineered products employing heparin-loaded nanoplatforms

The enhancement of hemocompatibility through the use of nanoplatforms loaded with heparin represents a highly desirable characteristic in the context of emerging tissue engineering applications. The significance of employing heparin in biological processes is unquestionable, owing to its ability to interact with a diverse range of proteins. It plays a crucial role in numerous biological processes by engaging in interactions with diverse proteins and hydrogels. This review provides a summary of recent endeavors focused on augmenting the hemocompatibility of tissue engineering methods through the utilization of nanoplatforms loaded with heparin. This study also provides a comprehensive review of the various applications of heparin-loaded nanofibers and nanoparticles, as well as the techniques employed for encapsulating heparin within these nanoplatforms. The biological and physical effects resulting from the encapsulation of heparin in nanoplatforms are examined. The potential applications of heparin-based materials in tissue engineering are also discussed, along with future perspectives in this field.

External Trigger Free Charge Switchable Cationic Ligands in the Design of Safe and Effective Universal Heparin Antidote

Thrombosis, the formation of blood clots within a blood vessel, can lead to severe complications including pulmonary embolism, cardiac arrest, and stroke. The most widely administered class of anticoagulants is heparin-based anticoagulants such as unfractionated heparin, low-molecular weight heparins (LMWHs), and fondaparinux. Protamine is the only FDA-approved heparin antidote. Protamine has limited efficacy neutralizing LMWHs and no reversal activity against fondaparinux. The use of protamine can lead to complications, including excessive bleeding, hypotension, and hypersensitivity, and has narrow therapeutic window. In this work, a new concept in the design of a universal heparin antidote: switchable protonation of cationic ligands, is presented. A library of macromolecular polyanion inhibitors (MPIs) is synthesized and screened to identify molecules that can neutralize all heparins with high selectivity and reduced toxicity. MPIs are developed by assembling cationic binding groups possessing switchable protonation states onto a polymer scaffold. By strategically selecting the identity and modulating the density of cationic binding groups on the polymer scaffold, a superior universal heparin reversal agent is developed with improved heparin-binding activity and increased hemocompatibility profiles leading to minimal effect on hemostasis. The activity of this heparin antidote is demonstrated using in vitro and in vivo studies.

Heparinized self-healing polymer coating with inflammation modulation for blood-contacting biomedical devices

The current techniques for antithrombotic coating on blood-contacting biomedical materials and devices are usually complex and lack practical feasibility with weak coating stability and low heparin immobilization. Here, a heparinized self-healing polymer coating with inflammation modulation is introduced through thermal-initiated radical copolymerization of methacrylate esterified heparin (MA-heparin) with methyl methacrylate (MMA) and n-butyl acrylate (nBA), followed by the anchoring of reactive oxygen species (ROS)-responsive polyoxalate containing vanillyl alcohol (PVAX) onto the coating through esterification. The aspirin, which is readily dissolved in the solution of MMA and nBA, is encapsulated within the coating after copolymerization. The copolymerization of MA-heparin with MMA and nBA significantly increases the heparin content of the coating, effectively inhibiting thrombosis and rendering the coating self-healing to help maintain long-term stability. ROS-responsive PVAX and aspirin released in a temperature-dependent manner resist acute and chronic inflammation, respectively. The heparinized self-healing and inflammation-modulated polymer coating exhibits the ability to confer long-term stability and hemocompatibility to blood-contacting biomedical materials and devices. STATEMENT OF SIGNIFICANCE: Surface engineering for blood-contacting biomedical devices paves a successful way to reduce thrombotic and inflammatory complications. However, lack of effectiveness, long-term stability and practical feasibility hinders the development and clinical application of existing strategies. Here we design a heparinized self-healing and inflammation-modulated polymer coating, which possesses high heparin level and self-healing capability to maintain long-term stability. The polymer coating is practically feasible to varied substrates and demonstrated to manipulate inflammation and prevent thrombosis both in vitro and in vivo. Our work provides a new method to develop coatings for blood-contacting biomedical materials and devices with long-term stability and hemocompatibility.

"Two-birds-one-stone" oral nanotherapeutic designed to target intestinal integrins and regulate redox homeostasis for UC treatment

Designing highly efficient orally administrated nanotherapeutics with specific inflammatory site-targeting functions in the gastrointestinal tract for ulcerative colitis (UC) management is a noteworthy challenge. Here, we focused on exploring a specific targeting oral nanotherapy, serving as "one stone," for the directed localization of inflammation and the regulation of redox homeostasis, thereby achieving effects against "two birds" for UC treatment. Our designed nanotherapeutic agent OPNs@LMWH (oxidation-sensitive ε-polylysine nanoparticles at low-molecular weight heparin) exhibited specific active targeting effects and therapeutic efficacy simultaneously. Our results indicate that OPNs@LMWH had high integrin αM-mediated immune cellular uptake efficiency and preferentially accumulated in inflamed tissues. We also confirmed its effectiveness in the treatment experiment of colitis in mice by ameliorating oxidative stress and inhibiting the activation of inflammation-associated signaling pathways while simultaneously bolstering the protective mechanisms of the colonic epithelium. Overall, these findings underscore the compelling dual functionalities of OPNs@LMWH, which enable effective oral delivery to inflamed sites, thereby facilitating precise UC management.

Design Principles for Immunomodulatory Biomaterials

The immune system is imperative to the survival of all biological organisms. A functional immune system protects the organism by detecting and eliminating foreign and host aberrant molecules. Conversely, a dysfunctional immune system characterized by an overactive or weakened immune system causes life-threatening autoimmune or immunodeficiency diseases. Therefore, a critical need exists to develop technologies that regulate the immune system to ensure homeostasis or treat several diseases. Accumulating evidence shows that biomaterials─artificial materials (polymers, metals, ceramics, or engineered cells and tissues) that interact with biological systems─can trigger immune responses, offering a materials science-based strategy to modulate the immune system. This Review discusses the expanding frontiers of biomaterial-based immunomodulation, focusing on principles for designing these materials. This Review also presents examples of immunomodulatory biomaterials, which include polymers and metal- and carbon-based nanomaterials, capable of regulating the innate and adaptive immune systems.

Ion Mobility Mass Spectrometry-Based Disaccharide Analysis of Glycosaminoglycans

Glycosaminoglycans (GAGs) are linear and acidic polysaccharides. They are ubiquitous molecules, which are involved in a wide range of biological processes. Despite being structurally simple at first glance, with a repeating backbone of alternating hexuronic acid and hexosamine dimers, GAGs display a highly complex structure, which predominantly results from their heterogeneous sulfation patterns. The commonly applied method for compositional analysis of all GAGs is "disaccharide analysis." In this process, GAGs are enzymatically depolymerized into disaccharides, derivatized with a fluorescent label, and then analysed through liquid chromatography. The limiting factor in the high throughput analysis of GAG disaccharides is the time-consuming liquid chromatography. To address this limitation, we here utilized trapped ion mobility-mass spectrometry (TIM-MS) for the separation of isomeric GAG disaccharides, which reduces the measurement time from hours to a few minutes. A full set of disaccharides comprises twelve structures, with eight possessing isomers. Most disaccharides cannot be differentiated by TIM-MS in underivatized form. Therefore, we developed chemical modifications to reduce sample complexity and enhance differentiability. Quantification is performed using stable isotope labelled standards, which are easily available due to the nature of the performed modifications.

Dextran-40 Reduces Partial Flap Failure: A Systematic Review and Meta-analysis for Antithrombotics after Free Flaps

Background

Antithrombotic agents are used after free-flap surgery to prevent thrombus formation and improve flap outcomes. However, the reports vary. Therefore, this meta-analysis aimed to elucidate the need for antithrombotic agents in this context.

Methods

We searched for studies that compared the outcomes of patients undergoing free-flap surgery with or without postoperative antithrombotic agents in the PubMed, Cochrane, and ClinicalTrials.gov databases. The primary outcome was total flap failure, with secondary outcomes including partial flap failure, pedicle thrombosis, and bleeding/hematoma. The relative risks (RRs) of outcomes with or without antithrombotic use were evaluated.

Results

Fifteen studies (n = 6755 cases) were included. Antithrombotic agents did not reduce flap failure or pedicle thrombosis risks but increased bleeding and hematoma risks (RR, 1.535). Subgroup analyses by antiplatelet and anticoagulant use demonstrated results similar to those of antithrombotic use. The RR of bleeding/hematoma was 1.761 and 2.740 in the antiplatelet and anticoagulant groups, respectively. Postoperative dextran-40 administration reduced the risk of partial flap failure, with an RR of 0.535.

Conclusions

Postoperative antithrombotic, antiplatelet, or anticoagulant use did not change the risk of total/partial flap failure or pedicle thrombosis but increased the risk of hematoma/bleeding. Postoperative use of dextran-40 reduced the risk of partial flap failure. Increased intraflap blood flow may decrease the risk of partial flap failure. However, dextran-40 may cause severe pulmonary distress. Further prospective studies are required to evaluate the effects of these agents on thrombus formation, intraflap blood flow, and partial flap failure risk.

Reversal and resumption of anticoagulants in patients with anticoagulant-associated intracerebral hemorrhage

The use of anticoagulants has become more frequent due to the progressive aging population and increased thromboembolic events. Consequently, the proportion of anticoagulant-associated intracerebral hemorrhage (AAICH) in stroke patients is gradually increasing. Compared with intracerebral hemorrhage (ICH) patients without coagulopathy, patients with AAICH may have larger hematomas, worse prognoses, and higher mortality. Given the need for anticoagulant reversal and resumption, the management of AAICH differs from that of conventional medical or surgical treatments for ICH, and it is more specific. Understanding the pharmacology of anticoagulants and identifying agents that can reverse their effects in the early stages are crucial for treating life-threatening AAICH. When patients transition beyond the acute phase and their vital signs stabilize, it is important to consider resuming anticoagulants at the right time to prevent the occurrence of further thromboembolism. However, the timing and strategy for reversing and resuming anticoagulants are still in a dilemma. Herein, we summarize the important clinical studies, reviews, and related guidelines published in the past few years that focus on the reversal and resumption of anticoagulants in AAICH patients to help implement decisive diagnosis and treatment strategies in the clinical setting.

Alpha gal syndrome, a relative not absolute contraindication to the use of bovine pericardium to close an intracardiac septal defect: a case report

BACKGROUND

Alpha-gal syndrome is an allergic condition in which individuals develop an immune-mediated hypersensitivity response when consuming red meat and its derived products. Its diagnosis is important in individuals undergoing cardiac surgery, as patients frequently require large doses of unfractionated heparin or the insertion of surgical implants, both of which are porcine or bovine in origin. There are currently no guidelines for heparin administration in alpha-gal patients, with even less knowledge regarding the long-term clinical implications of these patients after receiving bioprosthetic valve replacements or other prostheses.

CASE PRESENTATION

We present the case of a 31-year-old male who underwent cardiac surgery in the setting of alpha-gal syndrome for a large atrial septal defect (ASD) and mitral valve prolapse (MVP). The patient continues to do well one year after undergoing a mitral valve repair, tricuspid valve repair and an ASD closure using bovine pericardium. He sustained no adverse reaction to the use of heparin products or the presence of a bovine pericardial patch. This rare case was managed by a multidisciplinary team consisting of cardiothoracic surgery, cardiac anesthesiology, and allergy/immunology that led to an optimal outcome despite the patient's pertinent allergic history.

CONCLUSIONS

This case highlights that the use of bovine pericardium and porcine heparin to close septal defects in patients with milder forms of alpha-gal allergy can be considered if other options are not available. Further studies are warranted to investigate the long-term outcomes of such potential alpha-gal containing prostheses and heparin exposure and establish the optimal decision making algorithm and prophylactic regimen.

Millimeter-scale magnetic implants paired with a fully integrated wearable device for wireless biophysical and biochemical sensing

Implantable sensors can directly interface with various organs for precise evaluation of health status. However, extracting signals from such sensors mainly requires transcutaneous wires, integrated circuit chips, or cumbersome readout equipment, which increases the risks of infection, reduces biocompatibility, or limits portability. Here, we develop a set of millimeter-scale, chip-less, and battery-less magnetic implants paired with a fully integrated wearable device for measuring biophysical and biochemical signals. The wearable device can induce a large amplitude damped vibration of the magnetic implants and capture their subsequent motions wirelessly. These motions reflect the biophysical conditions surrounding the implants and the concentration of a specific biochemical depending on the surface modification. Experiments in rat models demonstrate the capabilities of measuring cerebrospinal fluid (CSF) viscosity, intracranial pressure, and CSF glucose levels. This miniaturized system opens the possibility for continuous, wireless monitoring of a wide range of biophysical and biochemical conditions within the living organism.

The effect of different dose of heparin using in peripheral arteriovenous synchronous blood exchange transfusion for neonatal hyperbilirubinemia

Background

To explore the optimal dosage of heparin in peripheral arteriovenous automatic synchronous exchange transfusion therapy for neonatal hyperbilirubinemia.

Methods

A total of 185 neonates received peripheral arteriovenous synchronous blood exchange transfusion for hyperbilirubinemia were enrolled from pediatric department of the Ganzhou People's Hospital between January 2018 and June 2020, which were randomly divided into four groups. On the basis of exchange transfusion, different dose of heparin was pumping at the bleeding site of artery (A: no heparin; B: 100 U/h heparin; C: 200 U/h heparin; D: 300 U/h heparin). The indexes of exchange transfusion efficacy, including total bilirubin conversion rate, indirect bilirubin conversion rate, hemoglobin concentration, the platelet number and APTT value was measured before and after therapy. The sites of artery puncture, the sites and rate of vascular occlusion were counted and analyzed.

M6229 Protects against Extracellular-Histone-Induced Liver Injury, Kidney Dysfunction, and Mortality in a Rat Model of Acute Hyperinflammation

Extracellular histones have been shown to act as DAMPs in a variety of inflammatory diseases. Moreover, they have the ability to induce cell death. In this study, we show that M6229, a low-anticoagulant fraction of unfractionated heparin (UFH), rescues rats that were challenged by continuous infusion of calf thymus histones at a rate of 25 mg histones/kg/h. Histone infusion by itself induced hepatic and homeostatic dysfunction characterized by elevated activity of hepatic enzymes (ASAT and ALAT) and serum lactate levels as well as by a renal dysfunction, which contributed to the significantly increased mortality rate. M6229 was able to restore normal levels of both hepatic and renal parameters at 3 and 9 mg M6229/kg/h and prevented mortality of the animals. We conclude that M6229 is a promising therapeutic agent to treat histone-mediated disease.

Oxidative stress in acute pulmonary embolism: emerging roles and therapeutic implications

Oxidative stress is an imbalance between the body's reactive oxygen species and antioxidant defense mechanisms. Oxidative stress is involved in the development of several cardiovascular diseases, such as pulmonary hypertension, atherosclerosis, and diabetes mellitus. A growing number of studies have suggested the potential role of oxidative stress in the pathogenesis of pulmonary embolism. Biomarkers of oxidative stress in pulmonary embolism have also been explored, such as matrix metalloproteinases, asymmetric dimethylarginine, and neutrophil/lymphocyte ratio. Here, we comprehensively summarize some oxidative stress mechanisms and biomarkers in the development of acute pulmonary embolism and summarize related treatments based on antioxidant stress to explore effective treatment strategies for acute pulmonary embolism.

Impact of early heparin therapy on mortality in critically ill patients with sepsis associated acute kidney injury: a retrospective study from the MIMIC-IV database

Background: Inflammatory-coagulation dysfunction plays an increasingly important role in sepsis associated acute kidney injury (SAKI). This study aimed to investigate whether early heparin therapy improves survival in patients with SAKI. Methods: Patients with SAKI were identified from the Medical Information Mart for Intensive Care-IV database. The patients were divided into two groups: those who received heparin subcutaneously within 48 h after intensive care unit (ICU) admission and the control group, who received no heparin. The primary endpoint was ICU mortality, the secondary outcomes were 7-day, 14-day, 28-day, and hospital mortality. Propensity score matching (PSM), marginal structural Cox model (MSCM), and E-value analyses were performed. Results: The study included 5623 individuals with SAKI, 2410 of whom received heparin and 3213 of whom did not. There were significant effects on ICU and 28-day mortality in the overall population with PSM. MSCM further reinforces the efficacy of heparin administration reduces ICU mortality in the general population. Stratification analysis with MSCM showed that heparin administration was associated with decreased ICU mortality at various AKI stages. Heparin use was also associated with reduced 28-day mortality in patients with only female, age >60 years, and AKI stage 3, with HRs of 0.79, 0.77, and 0.60, respectively (p < 0.05). E-value analysis suggests robustness to unmeasured confounding. Conclusion: Early heparin therapy for patients with SAKI decreased ICU mortality. Further analysis demonstrated that heparin therapy was associated with reduced 28-day mortality rate in patients only among female, age > 60 years and AKI stage 3.

Bivalirudin anticoagulation for cardiopulmonary bypass during cardiac surgery

INTRODUCTION

Heparin is the primary anticoagulant for cardiopulmonary bypass (CPB) support during cardiac surgery. While widely used, ∼2% of cardiac surgery patients develop heparin-induced thrombocytopenia (HIT) and 4-26% develop heparin resistance. Bivalirudin is an alternative anticoagulant mainly used for percutaneous coronary interventions. Given the challenges associated with heparin anticoagulation, we conducted a review to explore the use of bivalirudin for CPB surgery.

METHODS

PubMed and Embase scoping review included 2 randomized controlled trials, a retrospective comparison study, 3 pilot studies, and 30 case reports. To provide a contemporary series, we searched for articles published from 2010 to 2023. Our review included studies from both adult and pediatric populations.

RESULTS

While data is limited, bivalirudin seems to supply similar effectiveness and safety as heparin for CPB anticoagulation. Across the three comparative studies, the heparin cohorts had a 0-9% mortality rate and 0-27% rate of major bleeding/reoperation compared to a 0-3% mortality and 0-6% major bleeding/reoperation rate for the bivalirudin cohorts. Bivalirudin was successfully used as an anticoagulant in a wide range of CPB surgeries (e.g., heart transplants, ventricular assisted device placements, and valve repairs). Successful patient outcomes were reported with bivalirudin infusion of ∼2 mg/kg/hour, activated clotting time monitoring (target >400 s or 2.5× baseline), use of cardiotomy suctions, minimization of stagnant blood, and post-bypass modified ultrafiltration.

CONCLUSION

Bivalirudin is a safe and effective anticoagulant for CPB, especially for patients with HIT or heparin resistance. Further comparative research is called for to optimize bivalirudin utilization for CPB during cardiac surgery.

Heparin anticoagulation versus regional citrate anticoagulation for membrane therapeutic plasma exchange in patients with increased bleeding risk

Background Heparin anticoagulation (HA) is commonly employed for membrane therapeutic plasma exchange (mTPE). However, for patients with increased bleeding risk, there were controversial opinions on the use of HA versus regional citrate anticoagulation (RCA) for mTPE. Our present study aimed to evaluate the efficacy and safety of HA vs. RCA for mTPE in patients with increased bleeding risk.Methods Patients with increased bleeding risk who underwent mTPE between 2014 and 2021 in our center were screened. Observations of anticoagulation efficacy and safety were used as the study endpoints.Results A total of 108 patients with 368 mTPE sessions were included. Of the included patients, 38 and 70 received HA and RCA mTPE, respectively. There was no significant difference in the clotting of extracorporeal circuits between the HA and RCA groups (4.1% vs. 4.4%, p = 0.605). More bleeding episodes were observed in the HA group compared to the RCA group (16.4% vs. 4.4% mTPE sessions, p < 0.001). The frequency of postoperative transfusion within 24 h (11% vs. 3.4%, p = 0.007) was significantly different in the HA and RCA group. Anticoagulation strategy (HA vs. RCA; OR 5.659, 95%CI 2.266-14.129; p < 0.001), and mean arterial pressure (prior treatment, OR 1.052, 95%CI 1.019-1.086; p = 0.002) were independent risk factors of bleeding episodes. At the end of mTPE treatment, the incidence of metabolic alkalosis (16.7% vs. 54.1%, p = 0.027) and hypocalcemia (41.7% vs. 89.2%, p = 0.001) was significantly different in the HA (n = 5, 12 sessions) and RCA (n = 22, 74 sessions) groups, respectively.Conclusion RCA is as effective as HA for mTPE. However, for patients with increased bleeding risk, RCA is associated with a lower risk of bleeding, compared with HA. With careful monitoring and timely adjustment, RCA most likely is a safe and effective anticoagulation option for mTPE in patients with increased bleeding risk.

Anti-Inflammatory and Anticancer Effects of Anticoagulant Therapy in Patients with Malignancy

Optimizing the anticoagulation therapy is of pivotal importance in patients with a malignant tumor, as venous thromboembolism (VTE) has become the second-leading cause of death in this population. Cancer can highly increase the risk of thrombosis and bleeding. Consequently, the management of cancer-associated VTE is complex. In recent years, translational research has intensified, and several studies have highlighted the role of inflammatory cytokines in cancer growth and progression. Simultaneously, the pleiotropic effects of anticoagulants currently recommended for VTE have emerged. In this review, we describe the anti-inflammatory and anticancer effects of both direct oral anticoagulants (DOACs) and low-molecular-weight heparins (LWMHs).

Neutrophil extracellular traps mediate deep vein thrombosis: from mechanism to therapy

Deep venous thrombosis (DVT) is a part of venous thromboembolism (VTE) that clinically manifests as swelling and pain in the lower limbs. The most serious clinical complication of DVT is pulmonary embolism (PE), which has a high mortality rate. To date, its underlying mechanisms are not fully understood, and patients usually present with clinical symptoms only after the formation of the thrombus. Thus, it is essential to understand the underlying mechanisms of deep vein thrombosis for an early diagnosis and treatment of DVT. In recent years, many studies have concluded that Neutrophil Extracellular Traps (NETs) are closely associated with DVT. These are released by neutrophils and, in addition to trapping pathogens, can mediate the formation of deep vein thrombi, thereby blocking blood vessels and leading to the development of disease. Therefore, this paper describes the occurrence and development of NETs and discusses the mechanism of action of NETs on deep vein thrombosis. It aims to provide a direction for improved diagnosis and treatment of deep vein thrombosis in the near future.

Effects of low-dose intravenous heparin therapy in aneurysmal subarachnoid hemorrhage: a randomized controlled clinical trial protocol

BACKGROUND

Heparin anticoagulation therapy is a widely used method to prevent cerebral vasospasm (CV) and venous thrombosis in patients with subarachnoid hemorrhage caused by ruptured cerebral aneurysms. Subcutaneous heparin injection is considered safe and effective, whereas continuous intravenous heparin infusion is still being debated due to the risk of bleeding. Although most retrospective studies have confirmed the safety and effectiveness of unfractionated heparin (UFH) after aneurysm embolization therapy and its ability to reduce CV, there is still no randomized clinical trial comparing UFH and subcutaneous low-molecular-weight heparin (LMWH) injection in this population. Therefore, this study aims to compare the clinical outcomes associated with these two treatment approaches.

METHODS

The study is an open-label, single-center, randomized controlled trial and aims to recruit 456 patients, with 228 patients in each group. The primary outcome was CV; the second outcomes measures are occurrence of bleeding events, ischemic events, heparin-induced thrombocytopenia, deep vein thrombosis, cerebral venous circulation time, brain edema score, and hydrocephalus incidence.

ETHICS AND DISSEMINATION

This study protocol obtained ethical approval from the Ethics Committee of Baoan People's Hospital, Shenzhen, Guangdong (approval number: BYL20220805). This work will be published in peer-reviewed international medical journals and presented at medical conferences.

TRIAL REGISTRATION

ClinicalTrials ID: NCT05696639. Registered on March 30, 2023.

Enhancing bioavailability of natural extracts for nutritional applications through dry powder inhalers (DPI) spray drying: technological advancements and future directions

Natural ingredients have many applications in modern medicine and pharmaceutical projects. However, they often have low solubility, poor chemical stability, and low bioavailability in vivo. Spray drying technology can overcome these challenges by enhancing the properties of natural ingredients. Moreover, drug delivery systems can be flexibly designed to optimize the performance of natural ingredients. Among the various drug delivery systems, dry powder inhalation (DPI) has attracted much attention in pharmaceutical research. Therefore, this review will focus on the spray drying of natural ingredients for DPI and discuss their synthesis and application.

Cortical Spreading Depolarization and Delayed Cerebral Ischemia; Rethinking Secondary Neurological Injury in Subarachnoid Hemorrhage

Poor outcomes in Subarachnoid Hemorrhage (SAH) are in part due to a unique form of secondary neurological injury known as Delayed Cerebral Ischemia (DCI). DCI is characterized by new neurological insults that continue to occur beyond 72 h after the onset of the hemorrhage. Historically, it was thought to be a consequence of hypoperfusion in the setting of vasospasm. However, DCI was found to occur even in the absence of radiographic evidence of vasospasm. More recent evidence indicates that catastrophic ionic disruptions known as Cortical Spreading Depolarizations (CSD) may be the culprits of DCI. CSDs occur in otherwise healthy brain tissue even without demonstrable vasospasm. Furthermore, CSDs often trigger a complex interplay of neuroinflammation, microthrombi formation, and vasoconstriction. CSDs may therefore represent measurable and modifiable prognostic factors in the prevention and treatment of DCI. Although Ketamine and Nimodipine have shown promise in the treatment and prevention of CSDs in SAH, further research is needed to determine the therapeutic potential of these as well as other agents.

Thromboinflammatory challenges in stroke pathophysiology

Despite years of encouraging translational research, ischemic stroke still remains as one of the highest unmet medical needs nowadays, causing a tremendous burden to health care systems worldwide. Following an ischemic insult, a complex signaling pathway emerges leading to highly interconnected thrombotic as well as neuroinflammatory signatures, the so-called thromboinflammatory cascade. Here, we thoroughly review the cell-specific and time-dependent role of different immune cell types, i.e., neutrophils, macrophages, T and B cells, as key thromboinflammatory mediators modulating the neuroinflammatory response upon stroke. Similarly, the relevance of platelets and their tight crosstalk with a variety of immune cells highlights the relevance of this cell-cell interaction during microvascular dysfunction, neovascularization, and cellular adhesion. Ultimately, we provide an up-to-date overview of therapeutic approaches mechanistically targeting thromboinflammation currently under clinical translation, especially focusing on phase I to III clinical trials.

The effect of intraurethral heparin on inflammation and spongiofibrosis in a rat model of experimentally induced urethral trauma

AIM

To determine the effect of heparin administered during the early post urethral trauma period on inflammation and spongiofibrosis in rats.

MATERIALS AND METHODS

The study included 24 male rats that were randomized into 3 groups of 8 each. The urethra was traumatized using a 24-G needle sheath in all rats. Group 1 (control group) received intraurethral saline 0.9% injected b.i.d. for 27 days, group 2 received intraurethral Na-heparin (liquemine-Roche) 1500 IU kg^-1 injected b.i.d. for 27 days, and group 3 received intraurethral Na-heparin 1500 IU kg^-1 injected b.i.d and saline 0.9% s.i.d. for 27 days. On day 28 the rats' penises were degloved and penectomy was performed. Inflammation, spongiofibrosis, and congestion in the urethra were investigated in each group.

RESULTS

A statistically significant difference was found between the three groups (control, heparin, and heparin + saline) in the histopathological status of spongiofibrosis, inflammation, and congestion, respectively (P = 0.0001, P = 0.002, P = 0.0001). Severe spongiofibrosis was observed in six (75%) of the rats in group 1 (control group), whereas severe spongiofibrosis was not observed in group 2 (heparin) or group 3 (heparin + saline).

CONCLUSION

We observed that intraurethral Na-heparin 1500 IU kg^-1 injectioned during the early posturethral trauma period in rats significantly decreased inflammation, spongiofibrosis, and congestion.

Approaches to Assure Similarity between Pharmaceutical Heparins from Two Different Manufacturers

Pharmaceutical heparins from different manufacturers may present heterogeneities due to particular extraction and purification procedures or even variations in the raw material manipulation. Heparins obtained from different tissues also differ in their structure and activity. Nevertheless, there is an increased demand for more accurate assessments to ensure the similarities of pharmaceutical heparins. We propose an approach to accurately assess the similarity of these pharmaceutical preparations based on well-defined criteria, which are verified with a variety of refined analytical methods. We evaluate six commercial batches from two different manufacturers which were formulated with Brazilian or Chinese active pharmaceutical ingredients. Biochemical and spectroscopic methods and analysis based on digestion with heparinases were employed to evaluate the purity and structure of the heparins. Specific assays were employed to evaluate the biological activity. We observed minor but significant differences between the constitutive units of the heparins from these two manufacturers, such as the content of N-acetylated α-glucosamine. They also have minor differences in their molecular masses. These physicochemical differences have no impact on the anticoagulant activity but can indicate particularities on their manufacturing processes. The protocol we propose here for analyzing the similarity of unfractionated heparins is analogous to those successfully employed to compare low-molecular-weight heparins.

The role of extracellular histones in COVID-19

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had spread from China and, within 2 months, became a global pandemic. The infection from this disease can cause a diversity of symptoms ranging from asymptomatic to severe acute respiratory distress syndrome with an increased risk of vascular hyperpermeability, pulmonary inflammation, extensive lung damage, and thrombosis. One of the host defense systems against coronavirus disease 2019 (COVID-19) is the formation of neutrophil extracellular traps (NETs). Numerous studies on this disease have revealed the presence of elevated levels of NET components, such as cell-free DNA, extracellular histones, neutrophil elastase, and myeloperoxidase, in plasma, serum, and tracheal aspirates of severe COVID-19 patients. Extracellular histones, a major component of NETs, are clinically very relevant as they represent promising biomarkers and drug targets, given that several studies have identified histones as key mediators in the onset and progression of various diseases, including COVID-19. However, the role of extracellular histones in COVID-19 per se remains relatively underexplored. Histones are nuclear proteins that can be released into the extracellular space via apoptosis, necrosis, or NET formation and are then regarded as cytotoxic damage-associated molecular patterns that have the potential to damage tissues and impair organ function. This review will highlight the mechanisms of extracellular histone-mediated cytotoxicity and focus on the role that histones play in COVID-19. Thereby, this paper facilitates a bench-to-bedside view of extracellular histone-mediated cytotoxicity, its role in COVID-19, and histones as potential drug targets and biomarkers for future theranostics in the clinical treatment of COVID-19 patients.

Pharmacology of Heparin and Related Drugs: An Update

Heparin has been used extensively as an antithrombotic and anticoagulant for close to 100 years. This anticoagulant activity is attributed mainly to the pentasaccharide sequence, which potentiates the inhibitory action of antithrombin, a major inhibitor of the coagulation cascade. More recently it has been elucidated that heparin exhibits anti-inflammatory effect via interference of the formation of neutrophil extracellular traps and this may also contribute to heparin's antithrombotic activity. This illustrates that heparin interacts with a broad range of biomolecules, exerting both anticoagulant and nonanticoagulant actions. Since our previous review, there has been an increased interest in these nonanticoagulant effects of heparin, with the beneficial role in patients infected with SARS2-coronavirus a highly topical example. This article provides an update on our previous review with more recent developments and observations made for these novel uses of heparin and an overview of the development status of heparin-based drugs. SIGNIFICANCE STATEMENT: This state-of-the-art review covers recent developments in the use of heparin and heparin-like materials as anticoagulant, now including immunothrombosis observations, and as nonanticoagulant including a role in the treatment of SARS-coronavirus and inflammatory conditions.

Pharmacological Modulation by Low Molecular Weight Heparin of Purinergic Signaling in Cardiac Cells Prevents Arrhythmia and Lethality Induced by Myocardial Infarction

Background: Although several studies suggest that heparins prevent arrhythmias caused by acute myocardial infarction (AMI), the molecular mechanisms involved remain unclear. To investigate the involvement of pharmacological modulation of adenosine (ADO) signaling in cardiac cells by a low-molecular weight heparin (enoxaparin; ENOX) used in AMI therapy, the effects of ENOX on the incidences of ventricular arrhythmias (VA), atrioventricular block (AVB), and lethality (LET) induced by cardiac ischemia and reperfusion (CIR) were evaluated, with or without ADO signaling blockers. Methods: To induce CIR, adult male Wistar rats were anesthetized and subjected to CIR. Electrocardiogram (ECG) analysis was used to evaluate CIR-induced VA, AVB, and LET incidence, after treatment with ENOX. ENOX effects were evaluated in the absence or presence of an ADO A1-receptor antagonist (DPCPX) and/or an inhibitor of ABC transporter-mediated cAMP efflux (probenecid, PROB). Results: VA incidence was similar between ENOX-treated (66%) and control rats (83%), but AVB (from 83% to 33%) and LET (from 75% to 25%) incidences were significantly lower in rats treated with ENOX. These cardioprotective effects were blocked by either PROB or DPCPX. Conclusion: These results indicate that ENOX was effective in preventing severe and lethal arrhythmias induced by CIR due to pharmacological modulation of ADO signaling in cardiac cells, suggesting that this cardioprotective strategy could be promising in AMI therapy.

An Overview of Drug Delivery Nanosystems for Sepsis-Related Liver Injury Treatment

Sepsis, which is a systemic inflammatory response syndrome caused by infection, has high morbidity and mortality. Sepsis-related liver injury is one of the manifestations of sepsis-induced multiple organ syndrome. To date, an increasing number of studies have shown that the hepatic inflammatory response, oxidative stress, microcirculation coagulation dysfunction, and bacterial translocation play extremely vital roles in the occurrence and development of sepsis-related liver injury. In the clinic, sepsis-related liver injury is mainly treated by routine empirical methods on the basis of the primary disease. However, these therapies have some shortcomings, such as serious side effects, short duration of drug effects and lack of specificity. The emergence of drug delivery nanosystems can significantly improve drug bioavailability and reduce toxic side effects. In this paper, we reviewed drug delivery nanosystems designed for the treatment of sepsis-related liver injury according to their mechanisms (hepatic inflammation response, oxidative stress, coagulation dysfunction in the microcirculation, and bacterial translocation). Although much promising progress has been achieved, translation into clinical practice is still difficult. To this end, we also discussed the key issues currently facing this field, including immune system rejection and single treatment modalities. Finally, with the rigorous optimization of nanotechnology and the deepening of research, drug delivery nanosystems have great potential for the treatment of sepsis-related liver injury.

A Novel Reperfusion Strategy for Primary Percutaneous Coronary Intervention in Patients with Acute ST-Segment Elevation Myocardial Infarction: A Prospective Case Series

BACKGROUND

Ischemia reperfusion injury (IRI) remains a major problem in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI). We have developed a novel reperfusion strategy for PCI and named it "volume-controlled reperfusion (VCR)". The aim of the current study was to assess the safety and feasibility of VCR in patients with STEMI.

METHODS

Consecutive patients admitted to Beijing Chaoyang Hospital with STEMI were prospectively enrolled. The feasibility endpoint was procedural success. The safety endpoints included death from all causes, major vascular complications, and major adverse cardiac event (MACE), i.e., a composite of cardiac death, myocardial reinfarction, target vessel revascularization (TVR), and heart failure.

RESULTS

A total of 30 patients were finally included. Procedural success was achieved in 28 (93.3%) patients. No patients died during the study and no major vascular complications or MACE occurred during hospitalization. With the exception of one patient (3.3%) who underwent TVR three months after discharge, no patient encountered death (0.0%), major vascular complications (0.0%), or and other MACEs (0.0%) during the median follow-up of 16 months.

CONCLUSION

The findings of the pilot study suggest that VCR has favorable feasibility and safety in patients with STEMI. Further larger randomized trials are required to evaluate the effectiveness of VCR in STEMI patients.

Potency Adjusted Blended Heparin of Bovine, Ovine, and Porcine Heparin Exhibit Comparable Biologic Effects to Referenced Single-Sourced Porcine Heparin

Introduction: Bovine and ovine mucosa represent alternate anticoagulants to porcine mucosa for production of unfractionated heparin (UFH). Standardized heparins from various sources can be blended and potency adjusted, blended heparins exhibit comparable effects as single-sourced porcine UFH. This study evaluated the pharmacologic profile of blended heparin and compared their activities to that of single sourced porcine, ovine, and bovine heparins. Methods: The anticoagulant effects of gravimetric and potency-adjusted heparins were evaluated with aPTT, TT, anti-Xa, anti-IIa, ACT, and TGA studies. Protamine sulfate studies were used for neutralization potential of each of the individual heparins. Results: The potency-adjusted heparins demonstrated comparable aPTT, TT, anti-Xa, anti-IIa, and ACT values at all concentrations (U/mL). However, in gravimetric studies, bovine heparin consistently showed lower values with the exception of thrombin generation inhibition studies. The protamine sulfate neutralization studies demonstrated complete neutralization at all concentrations for the potency-adjusted heparins. However, at gravimetric concentrations, minor differences were noted in the neutralization profile in each of these heparins. Conclusion: These studies support the hypothesis that blended heparin from bovine, ovine, and porcine tissue, when standardized in unit-equivalent proportions, exhibits a comparable anticoagulant profile to the single species derived heparins.

Discovery of protein biomarkers for venous thromboembolism in non-small cell lung cancer patients through data-independent acquisition mass spectrometry

Objective

Non-small cell lung cancer (NSCLC) patients present a high incidence of venous thromboembolism (VTE) with poor prognosis. It is crucial to identify and diagnose VTE early. The study aimed to identify potential protein biomarkers and mechanism of VTE in NSCLC patients via proteomics research.

Methods

Proteomic analysis of the human plasma was performed through data-independent acquisition mass spectrometry for 20 NSCLC patients with VTE, and 15 NSCLC patients without VTE. Significantly differentially expressed proteins were analyzed by multiple bioinformatics method for further biomarker analysis.

Results

A total of 280 differentially expressed proteins were identified in VTE and non-VTE patients, where 42 were upregulated and 238 were downregulated. These proteins were involved in acute-phase response, cytokine production, neutrophil migration and other biological processes related to VTE and inflammation. Five proteins including SAA1, S100A8, LBP, HP and LDHB had significant change between VTE and non-VTE patients, with the area under the curve (AUC) were 0.8067, 0.8308, 0.7767, 0.8021, 0.8533, respectively.

Conclusions

SAA1, S100A8, LBP, HP and LDHB may serve as potential plasma biomarkers for diagnosis VTE in NSCLC patients.

Ultrasound-induced destruction of heparin-loaded microbubbles attenuates L-arginine-induced acute pancreatitis

PURPOSE

Acute pancreatitis (AP) involves sudden inflammation caused by abnormal activation of pancreatic enzymes. The mechanisms underlying AP include oxidative stress, high levels of inflammatory mediators and inflammatory cell infiltration. Heparin, a key therapeutic drug, exerts anti-inflammatory, antioxidative, and anticoagulative effects. However, safe and effective drug delivery remains an obstacle. This study is the first to investigate the therapeutic effects of heparin-loaded microbubbles (HPMB) combined with ultrasound (UHPMB) and the role of heparin in acoustic cavitation.

METHODS

The characteristics of the microbubbles, including particle size, concentration, release, stability, and development, were studied. Heparin concentration in the HPMB was measured, and heparin-induced anticoagulation was evaluated. Drug safety was explored using hemolysis and cell viability assessments. The ability of HPMB to alleviate oxidative stress and inflammation were investigated in vitro. L-arginine induces AP in vivo. UHPMB was used for AP treatment. Serum amylase levels were measured and pancreatic architecture and pathological features were evaluated to determine AP severity. In vivo efficacy was evaluated, and the underlying mechanism of heparin action during acoustic cavitation was explored.

RESULTS

HPMB was spherical and presented as an emulsion-like solution without aggregation. HPMB was visible and stable and effectively released the drug under ultrasound (US). HPMB and UHPMB led to lower AP severity than in the untreated group. US-targeted microbubble destruction (UTMD) enhanced the therapeutic effect by decreasing oxidative stress and inflammation in AP models without injuring vital organs. UHPMB regulated VEGF/Flt-1 and SOD-1 expression. HPMB can also mitigate oxidative stress and inflammation in H₂O₂-pretreated cells.

CONCLUSION

UHPMB exhibits a strong ability not only to selectively target pancreatic lesions and release heparin but also to provide efficient protection by inhibiting oxidative stress and inflammation.

Heparin and Heparin-Based Drug Delivery Systems: Pleiotropic Molecular Effects at Multiple Drug Resistance of Osteosarcoma and Immune Cells

One of the main problems of modern health care is the growing number of oncological diseases both in the elderly and young population. Inadequately effective chemotherapy, which remains the main method of cancer control, is largely associated with the emergence of multidrug resistance in tumor cells. The search for new solutions to overcome the resistance of malignant cells to pharmacological agents is being actively pursued. Another serious problem is immunosuppression caused both by the tumor cells themselves and by antitumor drugs. Of great interest in this context is heparin, a biomolecule belonging to the class of glycosaminoglycans and possessing a broad spectrum of biological activity, including immunomodulatory and antitumor properties. In the context of the rapid development of the new field of “osteoimmunology,” which focuses on the collaboration of bone and immune cells, heparin and delivery systems based on it may be of intriguing importance for the oncotherapy of malignant bone tumors. Osteosarcoma is a rare but highly aggressive, chemoresistant malignant tumor that affects young adults and is characterized by constant recurrence and metastasis. This review describes the direct and immune-mediated regulatory effects of heparin and drug delivery systems based on it on the molecular mechanisms of (multiple) drug resistance in (onco) pathological conditions of bone tissue, especially osteosarcoma.

Fibrin structure, viscoelasticity and lysis face the interplay of biorelevant polyions

PURPOSE OF REVIEW

In the past 5 decades, heparins have been widely used as anticoagulants in the prevention and treatment of thrombosis. Subsequent development of heparin variants of various size and charge facilitated the discovery of their multiple biological actions and nonanticoagulant benefits. Platelet-derived or microbial polyphosphates, as well as DNA released in the course of neutrophil extracellular trap-formation are additional polyanions, which can modulate the development and stability of thrombi associated with cancer or inflammation. In this review, we focus on the size-dependent and electric charge-dependent modulatory effects of the three polyanions of different chemical structure.

RECENT FINDINGS

The polycationic histones have been recognized as potential biomarkers and therapeutic targets in several diseases related to inflammation and thrombosis. Since combating histones with activated protein C or heparin could cause unwanted bleeding, the quest for nonanticoagulant histone-neutralizing agents is ongoing. Polyanions may neutralize or exaggerate certain histone-mediated effects depending on their electric charge, size and histone effects under investigation. Several prothrombotic effects of polyphosphates and DNA are also size-dependent.

SUMMARY

The efficiency of future therapeutics targeting prothrombotic polyanions or histones is not a simple matter of electric charge, but may rely on a delicate combination of size, charge and chemical composition.

Heparan Sulfate and Sialic Acid in Viral Attachment: Two Sides of the Same Coin?

Sialic acids and heparan sulfates make up the outermost part of the cell membrane and the extracellular matrix. Both structures are characterized by being negatively charged, serving as receptors for various pathogens, and are highly expressed in the respiratory and digestive tracts. Numerous viruses use heparan sulfates as receptors to infect cells; in this group are HSV, HPV, and SARS-CoV-2. Other viruses require the cell to express sialic acids, as is the case in influenza A viruses and adenoviruses. This review aims to present, in a general way, the participation of glycoconjugates in viral entry, and therapeutic strategies focused on inhibiting the interaction between the virus and the glycoconjugates. Interestingly, there are few studies that suggest the participation of both glycoconjugates in the viruses addressed here. Considering the biological redundancy that exists between heparan sulfates and sialic acids, we propose that it is important to jointly evaluate and design strategies that contemplate inhibiting the interactions of both glycoconjugates. This approach will allow identifying new receptors and lead to a deeper understanding of interspecies transmission.

Management of Anticoagulation during Extracorporeal Membrane Oxygenation in Children

Extracorporeal Membrane Oxygenation (ECMO) is often used in critically ill children with severe cardiopulmonary failure. Worldwide, about 3600 children are supported by ECMO each year, with an increase of 10% in cases per year. Although anticoagulation is necessary to prevent circuit thrombosis during ECMO support, bleeding and thrombosis are associated with significantly increased mortality risk. In addition, maintaining balanced hemostasis is a challenging task during ECMO support. While heparin is a standard anticoagulation therapy in ECMO, recently, newer anticoagulant agents are also in use. Currently, there is a wide variation in anticoagulation management and diagnostic monitoring in children receiving ECMO. This review intends to describe the pathophysiology of coagulation during ECMO support, review of literature on current and newer anticoagulant agents, and outline various diagnostic tests used for anticoagulation monitoring. We will also discuss knowledge gaps and future areas of research.

Remodeling of Structurally Reinforced (TPU+PCL/PCL)-Hep Electro-spun Small Diameter Bilayer Vascular Grafts Interposed in Rat Ab-dominal Aorta

As the thermoplastic polyurethane (TPU) elastomer possesses good biocompatibility and mechanical properties similar to native vascular tissues as well, it is intended to co-electrospin with poly(ε-caprolactone) (PCL) onto the outer...

Holothurian fucosylated chondroitin sulfates and their potential benefits for human health: Structures and biological activities

Fucosylated chondroitin sulfates (FCS) are a sulfated polysaccharide exclusively existing in the body wall of sea cucumber. FCS possesses a mammalian chondroitin sulfate like backbone, namely repeating disaccharides units composed of GlcA and GalNAc, with fucosyl branches linked to GlcA and/or GalNAc residues. It is found that FCS can prevent unhealthy dietary pattern-induced metabolic syndromes, including insulin resistance and β-cell function improvement, anti-inflammation, anti-hyperlipidemia, and anti-adipogenesis. Further studies show that those activities of FCS might be achieved through positively modulating gut microbiota composition. Besides, FCS also show therapeutic efficacy in cancer, HIV infection, and side effects of cyclophosphamide. Furthermore, bioactivities of FCS are closely affected by their molecular weights, sulfation pattern of the fucosyl branches, and chain conformations. This review summarizes the recent 20 years studies to provide references for the future studies and applications of FCS in functional foods or drugs.

Early prophylactic anticoagulation with heparin alleviates mortality in critically ill patients with sepsis: a retrospective analysis from the MIMIC-IV database

BACKGROUND

Minimal data exist on anticoagulation use and timing and the dose of heparin in patients with sepsis, and whether heparin use improves sepsis survival remains largely unclear. This study was performed to assess whether heparin administration would provide a survival advantage in critically ill patients with sepsis.

METHODS

A retrospective cohort study of patients with sepsis in the Medical Information Mart for Intensive Care (MIMIC)-IV database was conducted. Cox proportional hazards model and propensity score matching (PSM) were used to evaluate the outcomes of prophylactic anticoagulation with heparin administered by subcutaneous injection within 48 h of intensive care unit (ICU) admission. The primary outcome was in-hospital mortality. Secondary outcomes included 60-day mortality, length of ICU stay, length of hospital stay and incidence of acute kidney injury (AKI) on day 7. E-Value analysis were used for unmeasured confounding.

RESULTS

A total of 6646 adult septic patients were included and divided into an early prophylactic heparin group (n = 3211) and a nonheparin group (n = 3435). In-hospital mortality in the heparin therapy group was significantly lower than that in the nonheparin group (prematched 14.7 vs 20.0%, hazard ratio (HR) 0.77, 95% confidence interval (CI) [0.68-0.87], p < 0.001, and postmatched 14.9 vs 18.3%, HR 0.78, 95% CI [0.68-0.89], p < 0.001). Secondary endpoints, including 60-day mortality and length of ICU stay, differed between the heparin and nonheparin groups (p < 0.01). Early prophylactic heparin administration was associated with in-hospital mortality among septic patients in different adjusted covariates (HR 0.71-0.78, p < 0.001), and only administration of five doses of heparin was associated with decreased in-hospital mortality after PSM (HR 0.70, 95% CI 0.56-0.87, p < 0.001). Subgroup analysis showed that heparin use was significantly associated with reduced in-hospital mortality in patients with sepsis-induced coagulopathy, septic shock, sequential organ failure assessment score ≥ 10, AKI, mechanical ventilation, gram-positive bacterial infection and gram-negative bacterial infection, with HRs of 0.74, 0.70, 0.58, 0.74, 0.73, 0.64 and 0.72, respectively (p <0.001). E-Value analysis suggested robustness to unmeasured confounding.

CONCLUSIONS

This study found an association between early administration prophylactic heparin provided to patients with sepsis and reduced risk-adjusted mortality. A prospective randomized-controlled study should be designed to further assess the relevant findings.

How COVID-19 and other pathological conditions and medical treatments activate our intravascular innate immune system

COVID-19 has been shown to have a multifaceted impact on the immune system. In a recently published article in Front Immunol, we show that the intravascular innate immune system (IIIS) is strongly activated in severe COVID-19 with ARDS and appears to be one of the causes leading to severe COVID-19. In this article, we describe the IIIS and its physiological function, but also the strong pro-inflammatory effects that are observed in COVID-19 and in various other pathological conditions and treatments such as during ischemia reperfusion injury and in treatments where biomaterials come in direct contact with blood in, e.g., extracorporeal and intravasal treatments. In the present article, we describe how the IIIS, a complex network of plasma proteins and blood cells, constitute the acute innate immune response of the blood and discuss the effects that the IIIS induces in pathological disorders and treatments in modern medicine.

Safety and Efficacy of Intermediate- and Therapeutic-Dose Anticoagulation for Hospitalised Patients with COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

COVID-19 patients are at high thrombotic risk. The safety and efficacy of different anticoagulation regimens in COVID-19 patients remain unclear.

METHODS

We searched for randomised controlled trials (RCTs) comparing intermediate- or therapeutic-dose anticoagulation to standard thromboprophylaxis in hospitalised patients with COVID-19 irrespective of disease severity. To assess efficacy and safety, we meta-analysed data for all-cause mortality, clinical status, thrombotic event or death, and major bleedings.

RESULTS

Eight RCTs, including 5580 patients, were identified, with two comparing intermediate- and six therapeutic-dose anticoagulation to standard thromboprophylaxis. Intermediate-dose anticoagulation may have little or no effect on any thrombotic event or death (RR 1.03, 95% CI 0.86-1.24), but may increase major bleedings (RR 1.48, 95% CI 0.53-4.15) in moderate to severe COVID-19 patients. Therapeutic-dose anticoagulation may decrease any thrombotic event or death in patients with moderate COVID-19 (RR 0.64, 95% CI 0.38-1.07), but may have little or no effect in patients with severe disease (RR 0.98, 95% CI 0.86-1.12). The risk of major bleedings may increase independent of disease severity (RR 1.78, 95% CI 1.15-2.74).

CONCLUSIONS

Certainty of evidence is still low. Moderately affected COVID-19 patients may benefit from therapeutic-dose anticoagulation, but the risk for bleeding is increased.

Heparin and Its Derivatives: Challenges and Advances in Therapeutic Biomolecules

Heparin has been extensively studied as a safe medicine and biomolecule over the past few decades. Heparin derivatives, including low-molecular-weight heparins (LMWH) and heparin pentasaccharide, are effective anticoagulants currently used in clinical settings. They have also been studied as functional biomolecules or biomaterials for various therapeutic uses to treat diseases. Heparin, which has a similar molecular structure to heparan sulfate, can be used as a remarkable biomedicine due to its uniquely high safety and biocompatibility. In particular, it has recently drawn attention for use in drug-delivery systems, biomaterial-based tissue engineering, nanoformulations, and new drug-development systems through molecular formulas. A variety of new heparin-based biomolecules and conjugates have been developed in recent years and are currently being evaluated for use in clinical applications. This article reviews heparin derivatives recently studied in the field of drug development for the treatment of various diseases.

Optimization of Heparin Monitoring with Anti-FXa Assays and the Impact of Dextran Sulfate for Measuring All Drug Activity

Heparins, unfractionated or low molecular weight, are permanently in the spotlight of both clinical indications and laboratory monitoring. An accurate drug dosage is necessary for an efficient and safe therapy. The one-stage kinetic anti-FXa assays are the most widely and universally used with full automation for large series, without needing exogenous antithrombin. The WHO International Standards are available for UFH and LMWH, but external quality assessment surveys still report a high inter-assay variability. This heterogeneity results from the following: assay formulation, designed without or with dextran sulfate to measure all heparin in blood circulation; calibrators for testing UFH or LMWH with the same curve; and automation parameters. In this study, various factors which impact heparin measurements are reviewed, and we share our experience to optimize assays for testing all heparin anticoagulant activities in plasma. Evidence is provided on the usefulness of low molecular weight dextran sulfate to completely mobilize all of the drug present in blood circulation. Other key factors concern the adjustment of assay conditions to obtain fully superimposable calibration curves for UFH and LMWH, calibrators' formulations, and automation parameters. In this study, we illustrate the performances of different anti-FXa assays used for testing heparin on UFH or LMWH treated patients' plasmas and obtained using citrate or CTAD anticoagulants. Comparable results are obtained only when the CTAD anticoagulant is used. Using citrate as an anticoagulant, UFH is underestimated in the absence of dextran sulfate. Heparin calibrators, adjustment of automation parameters, and data treatment contribute to other smaller differences.

Similarities and perspectives on the two C's-Cancer and COVID-19

COVID-19 continues to dominate the health-care burden in the twenty-first century. While health-care professionals around the world try their best to minimize the mortality from this pandemic, we also continue to battle the high mortality from different types of cancer. For the hemostasis and thrombosis specialist, these two conditions present some unusual similarities including the high rate of thrombosis and marked elevation of D-dimers. In this forum article, we discuss these similarities and provide some considerations for future research and therapeutic trials.

Circulating Histones in Sepsis: Potential Outcome Predictors and Therapeutic Targets

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection and is associated with high morbidity and mortality. Circulating histones (CHs), a group of damage-associated molecular pattern molecules mainly derived from neutrophil extracellular traps, play a crucial role in sepsis by mediating inflammation response, organ injury and death through Toll-like receptors or inflammasome pathways. Herein, we first elucidate the molecular mechanisms of histone-induced inflammation amplification, endothelium injury and cascade coagulation activation, and discuss the close correlation between elevated level of CHs and disease severity as well as mortality in patients with sepsis. Furthermore, current state-of-the-art on anti-histone therapy with antibodies, histone-binding proteins (namely recombinant thrombomodulin and activated protein C), and heparin is summarized to propose promising approaches for sepsis treatment.

Review: Inhibitory potential of low molecular weight Heparin in cell adhesion; emphasis on tumor metastasis

Low molecular weight heparin is a Heparin derivative, produced from commercial-grade Heparin through Chemical or enzymatic depolymerization. LMWH has remained a favored regimen for anticoagulation in cancer patients. Evidence from several studies has suggested that LMWHs possess antitumor and antimetastatic activity aside from their anticoagulant activity. Cancer metastasis is the foremost reason for cancer-related motility rate. Studies have pointed out that adhesion molecules play a decisive role in enhancing recurrent, invasive, and distant metastasis. Therefore, it is hypothesized that Cell adhesion molecules can be determined as a potential therapeutic target group, as antibodies or small-molecule inhibitors could easily access their extracellular domains. Furthermore, data from several investigations have reported LWMH potential effects as antimetastatic agents through influencing cell adhesion molecules. This review's objective is to emphasize the evidence available for the effects of the LMWHs in cell adhesion to inhibit tumor metastasis.