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PLoS Pathogens Jun 2024COVID-associated coagulopathy seemly plays a key role in post-acute sequelae of SARS- CoV-2 infection. However, the underlying pathophysiological mechanisms are poorly...
COVID-associated coagulopathy seemly plays a key role in post-acute sequelae of SARS- CoV-2 infection. However, the underlying pathophysiological mechanisms are poorly understood, largely due to the lack of suitable animal models that recapitulate key clinical and pathological symptoms. Here, we fully characterized AC70 line of human ACE2 transgenic (AC70 hACE2 Tg) mice for SARS-CoV-2 infection. We noted that this model is highly permissive to SARS-CoV-2 with values of 50% lethal dose and infectious dose as ~ 3 and ~ 0.5 TCID50 of SARS-CoV-2, respectively. Mice infected with 105 TCID50 of SARS-CoV-2 rapidly succumbed to infection with 100% mortality within 5 days. Lung and brain were the prime tissues harboring high viral titers, accompanied by histopathology. However, viral RNA and inflammatory mediators could be detectable in other organs, suggesting the nature of a systemic infection. Lethal challenge of AC70 hACE2 Tg mice caused acute onset of leukopenia, lymphopenia, along with an increased neutrophil-to-lymphocyte ratio (NLR). Importantly, infected animals recapitulated key features of COVID-19-associated coagulopathy. SARS-CoV-2 could induce the release of circulating neutrophil extracellular traps (NETs), along with activated platelet/endothelium marker. Immunohistochemical staining with anti-platelet factor-4 (PF4) antibody revealed profound platelet aggregates especially within blocked veins of the lungs. We showed that acute SARS-CoV-2 infection triggered a hypercoagulable state coexisting with ill-regulated fibrinolysis. Finally, we highlighted the potential role of Annexin A2 (ANXA2) in fibrinolytic failure. ANXA2 is a calcium-dependent phospholipid-binding protein that forms a heterotertrameric complexes localized at the extracellular membranes with two S100A10 small molecules acting as a co-receptor for tissue-plasminogen activator (t-PA), tightly involved in cell surface fibrinolysis. Thus, our results revealing elevated IgG type anti-ANXA2 antibody production, downregulated de novo ANXA2/S100A10 synthesis, and reduced ANXA2/S100A10 association in infected mice, this protein might serve as druggable targets for development of antithrombotic and/or anti-fibrinolytic agents to attenuate pathogenesis of COVID-19.
PubMed: 38913740
DOI: 10.1371/journal.ppat.1011777 -
Cureus May 2024A hemodialysis tunneled catheter is one option for vascular access used with hemodialysis patients; however, catheter complications such as thrombosis are still...
INTRODUCTION
A hemodialysis tunneled catheter is one option for vascular access used with hemodialysis patients; however, catheter complications such as thrombosis are still inevitable. To prevent thrombosis formation, a catheter-locking solution is instilled between dialysis sessions. Heparin is used as a default locking solution in our Hemodialysis Care Project centers, while a recombinant tissue plasminogen activator (rt-PA) such as alteplase is used to treat suspected catheter thrombosis. This study aimed to identify the clinical factors, catheter brands, and hemodialysis variables that influence the choice of use for alteplase versus heparin, for those patients with tunneled catheters, and reduce overprescribing of high-alert medication alteplase.
METHODS
A retrospective medical chart review study was conducted involving 230 patients with tunneled catheters; the first group of 133 patients used alteplase regularly three times a week, while the second group of 97 patients completed at least one year using the same catheter access with heparin lock only.
RESULTS
Multivariate logistic regression and logistic regression analysis showed a significant association (p < 0.05) between different variables. Results suggest that overweight and hyperlipidemia patients are more likely to use alteplase. Patients using brand-name catheters such as Hemostar/Vas-cath (BD, Franklin Lakes, NJ) are less likely to use heparin than those using Medcomp catheters (Medcomp, Yuma, AZ). In addition, patients having a history of angioplasty would be less likely to have heparin than no angioplasty. Moreover, if the patient's fluid removal were equal to or less than 2 kg, they would be more likely to use heparin and vice versa.
CONCLUSION
The study postulates that identified variables affect whether alteplase or heparin is used in hemodialysis tunneled catheters, and may be useful to increase awareness, improve practices, or judiciously control the use of alteplase within Saudi Arabia and globally.
PubMed: 38910780
DOI: 10.7759/cureus.60817 -
The Journal of Reproduction and... Jun 2024Understanding how stress hormones induce apoptosis in oviductal epithelial cells (OECs) and mural granulosa cells (MGCs) can reveal the mechanisms by which female stress...
Understanding how stress hormones induce apoptosis in oviductal epithelial cells (OECs) and mural granulosa cells (MGCs) can reveal the mechanisms by which female stress impairs embryonic development and oocyte competence. A recent study showed that tissue plasminogen activator (tPA) ameliorates corticosterone-induced apoptosis in MGCs and OECs by acting on its receptors low-density lipoprotein receptor-related protein 1 (LRP1) and Annexin A2 (ANXA2), respectively. However, whether tPA is involved in corticotropin-releasing hormone (CRH)-induced apoptosis and whether it uses the same or different receptors to inhibit apoptosis induced by different hormones in the same cell type remains unknown. This study showed that CRH triggered apoptosis in both OECs and MGCs and significantly downregulated tPA expression. Moreover, tPA inhibits CRH-induced apoptosis by acting on ANXA2 in both OECs and MGCs. While ANXA2 inhibits apoptosis via phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling, LRP1 reduces apoptosis via mitogen-activated protein kinase (MAPK) signaling. Thus, tPA used the same receptor to inhibit CRH-induced apoptosis in both OECs and MGCs, however used different receptors to inhibit corticosterone-induced apoptosis in MGCs and OECs. These data helps understand the mechanism by which female stress impairs embryo/oocyte competence and proapoptotic factors trigger apoptosis in different cell types.
PubMed: 38910127
DOI: 10.1262/jrd.2024-028 -
Thrombosis Research Jun 2024Spontaneous echo contrast (SEC) and left atrial appendage thrombus (LAAT) increase the risk of stroke and its severity in patients with atrial fibrillation (AF)....
INTRODUCTION
Spontaneous echo contrast (SEC) and left atrial appendage thrombus (LAAT) increase the risk of stroke and its severity in patients with atrial fibrillation (AF). Formation of denser fibrin networks and impaired fibrinolysis are associated with stroke risk in AF. This study investigated whether the prothrombotic fibrin clot phenotype characterizes patients with SEC/LAAT.
METHODS
We studied 139 anticoagulated patients with AF (median age, 70 years), who underwent transesophageal echocardiography (TEE). SEC and LAAT were recorded. We assessed plasma fibrin clot properties, i.e. permeability (K) and clot lysis time (CLT), von Willebrand Factor (vWF) antigen, endogenous thrombin potential (ETP), proteins involved in thrombosis and fibrinolysis, as well as plasma carbonylated protein content (PC).
RESULTS
SEC/LAAT was identified in 36 subjects (25.9 %) and was associated with heart failure (HF), AF duration, higher CHADSVASc score, N-terminal prohormone of brain natriuretic peptide, and growth differentiation factor 15. Patients with SEC/LAAT had lower K (-15 %) and prolonged CLT (+19 %), along with higher fibrinogen (+24 %), ETP (+3 %), and plasminogen activator inhibitor-1 antigen (+16 %) compared with the remainder. Thrombin-activatable fibrinolysis inhibitor antigen, plasminogen, α - antiplasmin, and tissue plasminogen activator antigen were similar between the two groups. PC content was 50 % higher in SEC/LAAT and correlated with Ks (r = -0.47, p < 0.001) and CLT (r = 0.40, p < 0.001). On multivariate analysis, Ks, CLT, and PC levels, along with HF, remained independently associated with SEC/LAAT.
CONCLUSIONS
We demonstrated a formation of denser and poorly lysable fibrin networks in AF patients with SEC/LAAT despite anticoagulation. We suggest that this phenomenon is in part related to enhanced oxidative stress.
PubMed: 38908317
DOI: 10.1016/j.thromres.2024.109065 -
JOR Spine Jun 2024Numerous investigations have suggested links between circulating inflammatory proteins (CIPs) and spinal degenerative diseases (SDDs), but causality has not been proven....
BACKGROUND
Numerous investigations have suggested links between circulating inflammatory proteins (CIPs) and spinal degenerative diseases (SDDs), but causality has not been proven. This study used Mendelian randomization (MR) to investigate the causal associations between 91 CIPs and cervical spondylosis (CS), prolapsed disc/slipped disc (PD/SD), spinal canal stenosis (SCS), and spondylolisthesis/spondylolysis.
METHODS
Genetic variants data for CIPs and SDDs were obtained from the genome-wide association studies (GWAS) database. We used inverse variance weighted (IVW) as the primary method, analyzing the validity and robustness of the results through pleiotropy and heterogeneity tests and performing reverse MR analysis to test for reverse causality.
RESULTS
The IVW results with Bonferroni correction indicated that beta-nerve growth factor (β-NGF), C-X-C motif chemokine 6 (CXCL6), and interleukin-6 (IL-6) can increase the risk of CS. Fibroblast growth factor 19 (FGF19), sulfotransferase 1A1 (SULT1A1), and tumor necrosis factor-beta (TNF-β) can increase PD/SD risk, whereas urokinase-type plasminogen activator (u-PA) can decrease the risk of PD/SD. FGF19 and TNF can increase SCS risk. STAM binding protein (STAMBP) and T-cell surface glycoprotein CD6 isoform (CD6 isoform) can increase the risk of spondylolisthesis/spondylolysis, whereas monocyte chemoattractant protein 2 (MCP2) and latency-associated peptide transforming growth factor beta 1 (LAP-TGF-β1) can decrease spondylolisthesis/spondylolysis risk.
CONCLUSIONS
MR analysis indicated the causal associations between multiple genetically predicted CIPs and the risk of four SDDs (CS, PD/SD, SCS, and spondylolisthesis/spondylolysis). This study provides reliable genetic evidence for in-depth exploration of the involvement of CIPs in the pathogenic mechanism of SDDs and provides novel potential targets for SDDs.
PubMed: 38895179
DOI: 10.1002/jsp2.1346 -
International Journal of Molecular... May 2024Stress exposure worsens allergic inflammatory diseases substantially. Mast cells (MCs) play a key role in peripheral immune responses to neuroendocrine stress mediators...
Stress exposure worsens allergic inflammatory diseases substantially. Mast cells (MCs) play a key role in peripheral immune responses to neuroendocrine stress mediators such as nerve growth factor (NGF) and substance P (SP). Mast cell proteases (MCPs) and cholinergic factors (Chrna7, SLURP1) were recently described to modulate MC stress response. We studied MCPs and Chrna7/SLURP1 and their interplay in a mouse model for noise induced stress (NiS) and atopic dermatitis-like allergic inflammation (AlD) and in cultured MC lacking Chrna7. We found that the cholinergic stress axis interacts with neuroendocrine stress mediators and stress-mediator cleaving enzymes in AlD. SP-cleaving mMCP4+ MC were upregulated in AlD and further upregulated by stress in NiS+AlD. Anti-NGF neutralizing antibody treatment blocked the stress-induced upregulation in vivo, and mMCP4+ MCs correlated with measures of AlD disease activity. Finally, high mMCP4 production in response to SP depended on Chrna7/SLURP1 in cultured MCs. In conclusion, mMCP4 and its upstream regulation by Chrna7/SLURP1 are interesting novel targets for the treatment of allergic inflammation and its aggravation by stress.
Topics: Animals; Mast Cells; Dermatitis, Atopic; Mice; Disease Models, Animal; Skin; alpha7 Nicotinic Acetylcholine Receptor; Inflammation; Peptide Hydrolases; Urokinase-Type Plasminogen Activator; Substance P; Stress, Physiological; Mice, Inbred C57BL; Nerve Growth Factor
PubMed: 38891925
DOI: 10.3390/ijms25115738 -
ARYA Atherosclerosis 2023Primary percutaneous coronary intervention (PPCI) is the gold standard approach to restore blood flow in ST-segment elevation myocardial infarction (STEMI); however, the...
INTRODUCTION
Primary percutaneous coronary intervention (PPCI) is the gold standard approach to restore blood flow in ST-segment elevation myocardial infarction (STEMI); however, the no-reflow phenomenon as a potential complication of PPCI can worsen the outcomes. It has been hypothesized that adjunctive prophylactic intracoronary infusion of low-dose fibrinolytic might improve the PPCI outcomes; however, this theory is a matter of debate. The current study aims to investigate the value of adjunctive prophylactic intracoronary low-dose alteplase to prevent the no-reflow phenomenon in patients with STEMI.
METHOD
This case-control study was conducted on 80 STEMI patients who underwent PPCI. The patients were assigned into the case group who were intervened by 10 mg adjunctive intracoronary alteplase immediately at the end of the balloon angioplasty (n=40) and controls (n=40) who underwent conventional PPCI only. The angioplasty-associated outcomes including final TIMI score, need for no-reflow treatment, ST-segment resolution, post-PPCI complications, and death were compared between the groups.
RESULTS
Alteplase use was accompanied by significantly improved final TIMI flow scores (P-value<0.001) and fewer requirements for no-reflow treatments (P-value<0.001); however, it did not improve the ST-segment resolution (P-value=0.491). The mortality rate and post-angioplasty complications did not differ between the groups (P-value>0.05).
CONCLUSION
Based on the findings of this study, adjunctive infusion of low-dose intracoronary alteplase during PPCI could not efficiently prevent the no-reflow phenomenon. Although the final TIMI flow and need for post-stenting no-reflow treatment improved, ST-segment resolution did not occur dramatically. Given that, this approach requires further investigations and should be considered cautiously.
PubMed: 38883855
DOI: 10.48305/arya.2023.41614.2890 -
Journal of Thoracic Disease May 2024There is no established standard 3 line treatment for patients with advanced non-small cell lung cancer (NSCLC). Although cytotoxic chemotherapeutic agents that are not...
Treatment rationale and protocol design: an investigator-initiated phase II study of combination treatment of nivolumab and TM5614, a PAI-1 inhibitor for previously treated patients with non-small cell lung cancer.
BACKGROUND
There is no established standard 3 line treatment for patients with advanced non-small cell lung cancer (NSCLC). Although cytotoxic chemotherapeutic agents that are not used as 1 or 2 line treatment are administrated as 3 line treatment, their anti-tumor efficacy is insufficient. Anti-programmed death ligand-1 (PD-L1)/programmed death-1 (PD1) treatment is more effective and less toxic than chemotherapy in anti-PD-L1/PD-1 treatment-naïve patients with NSCLC. Therefore, anti-PD-L1/PD-1 therapy is considered an appropriate 3 line treatment. However, the anti-tumor efficacy is limited in patients previously treated with anti-PD-L1/PD-1 antibody. Today, new drugs are needed to increase the efficacy of anti-PD-L1/PD-1 antibodies.
METHODS
This open-label, single-arm, investigator-initiated phase II study is designed to evaluate combination treatment of nivolumab and TM5614, a plasminogen activator inhibitor (PAI-1) inhibitor as 3 or more line treatment in NSCLC patients who underwent standard treatment. The primary endpoint is the objective response rate and the secondary endpoints are progression-free survival (PFS), overall survival (OS), duration of response (DOR) and safety. Recruitment began in September 2023 and is expected to continue for approximately three years.
DISCUSSION
Currently, there is no standard 3 line treatment for advanced NSCLC, and we hope that the findings of this study will facilitate more effective treatments in this setting. Ethics and dissemination: the study protocol conformed to the ethical principles outlined in the Declaration of Helsinki. All patients will provide written informed consent prior to enrollment. Results will be published in a peer-reviewed publication.
TRIAL REGISTRATION
This study is registered to Japan Registry of Clinical Trials with number: jRCT2061230039 (19/July/2023).
PubMed: 38883673
DOI: 10.21037/jtd-23-1858 -
Journal of Thoracic Disease May 2024Little is known about the role of complement activation in acute pulmonary embolism (PE). We investigated whether complement activation is associated with the severity...
BACKGROUND
Little is known about the role of complement activation in acute pulmonary embolism (PE). We investigated whether complement activation is associated with the severity of acute PE, along with the associated prothrombotic state, systemic inflammation and neutrophil extracellular traps (NETs) formation.
METHODS
We studied 109 normotensive, non-cancer PE patients (aged 58.1±15.0 years). On admission prior to initiation of anticoagulation, plasma soluble complement components, i.e., C3a and sC5b-9, were measured with enzyme-linked immunosorbent assay (ELISA), along with thrombin generation, fibrinolysis proteins (plasminogen, antiplasmin, plasminogen activator inhibitor-1), factor VIII (FVIII) activity, and fibrin clot properties, including clot permeability (K, a measure of clot density) and clot lysis time (CLT). Moreover, we determined inflammatory markers and citrullinated histone H3, a specific marker of NETs formation.
RESULTS
Patients in the lower tertile of C3a (≤1.45 ng/mL, n=37) had lower simplified Pulmonary Embolism Severity Index (sPESI) values and were less likely to have right ventricular (RV) dysfunction compared to the remaining subjects. The former subgroup also had 13% lower FVIII activity, but not fibrinogen, interleukin-6, fibrinolysis proteins, and thrombin generation. Plasma C3a levels correlated inversely with K and positively with CLT indicating formation of denser and poorly lysable clots in subjects with elevated C3a. Despite a positive association between C3a and sC5b-9, the latter parameter was solely associated with higher FVIII, but not with other variables.
CONCLUSIONS
We showed that in acute PE enhanced complement activation characterizes patients with poorer short-term prognosis who display prothrombotic fibrin clot properties and elevated FVIII, which supports the involvement of complement proteins in acute thromboembolism.
PubMed: 38883666
DOI: 10.21037/jtd-24-171 -
Cureus May 2024The no-reflow phenomenon is defined as the failure to restore coronary flow demonstrated by the reduced or missing flow in angiography despite the patent artery. There...
The no-reflow phenomenon is defined as the failure to restore coronary flow demonstrated by the reduced or missing flow in angiography despite the patent artery. There are pharmacological strategies proposed and studied to manage the no-reflow phenomenon. The medication groups used are purine nucleoside (adenosine), calcium channel blockers (verapamil, nicardipine), beta 2 receptor agonists (adrenaline, nitroprusside), fibrinolytic agents (streptokinase, tissue plasminogen activators), glycoprotein IIb/IIIa inhibitors (abciximab, tirofiban). We present a case of a woman hospitalized in non-ST elevation myocardial infarction (NSTEMI) conditions. The patient underwent coronary angiography, in which a single vessel coronary artery disease (CAD); left anterior descending (LAD) stenosis of 90% was found. In this condition, the patient underwent percutaneous coronary intervention (PCI) of LAD. The no-reflow phenomenon occurred with thrombolysis in myocardial infarction (TIMI) flow grade of 0 during the procedure. As a consequence, the patient presented chest pain and important hypotension (BP of 70/45). Because of the hypotensive state of the patient, we decided to administer intracoronary (IC) adrenaline directly. In our case, we used adrenaline as a first-line treatment for the no-flow phenomenon due to the hypotensive state during the PCI procedure. Generally, we initially use IC nitrate or IC adenosine to resolve the phenomenon, and when the no-reflow persists we use IC adrenaline because of its side effects mentioned above. Anyway, we believe that in specific cases of hypotension and bradycardia, the use of adrenaline as the first line of therapy should be considered.
PubMed: 38883139
DOI: 10.7759/cureus.60338