Thromboelastography in acute immunologic reactions: a prospective pilot study.

Background: Biomarkers of fibrinolysis are elevated during acute immunologic reactions (allergic reactions and angioedema), although it is unclear whether fibrinolysis is associated with disease severity. Objectives: We investigated a possible association between maximum lysis (ML) measured by thromboelastography and the severity of acute immunologic reactions. Methods: We recruited patients with acute immunologic reactions at a high-volume emergency department. Clinical disease severity at presentation and at the end of the emergency department stay was assessed using a 5-grade scale, ranging from local symptoms to cardiac arrest. We determined ML on admission by thromboelastography (ROTEM's extrinsic [EXTEM], and aprotinin [APTEM] tests), expressed as ML%. Hyperfibrinolysis was defined as an ML of >15% in EXTEM, which was reversed by adding aprotinin (APTEM). We used exact logistic regression to investigate an association between ML% and disease severity (grades 1 and 2 [mild] vs 3-5 [severe]) and between hyperfibrinolysis and disease severity. Results: We included 31 patients (71% female; median age, 52 [IQR, 35-58] years; 10 [32%] with a severe reaction). ML% was higher in patients with severe symptoms (21 [IQR, 12-100] vs 10 [IQR, 4-17]). Logistic regression found a significant association between ML% and symptom severity (odds ratio, 1.07; 95% CI, 1.01-1.21; P = .003). Hyperfibrinolysis was detected in 6 patients and found to be associated with severe symptoms (odds ratio, 17.59; 95% CI, 1.52-991.09; P = .02). D-dimer, tryptase, and immunoglobulin E concentrations increased with the severity of immunologic reactions. Conclusion: ML, quantified by thromboelastography, is associated with the severity of acute immunologic reactions.

CHI3L1 on fibrinolytic system imbalance in chronic rhinosinusitis with nasal polyp.

Background: Chronic rhinosinusitis (CRS) is an inflammatory disease affecting more than 10% of the global adult population. It is classified into Th1, Th2, and Th17 endotypes and eosinophilic and non-eosinophilic types. Th2-based inflammation and eosinophilic CRS (ECRS) are associated with tissue remodeling and fibrinolytic system impairment. Objective: To elucidate the role of eosinophils in inducing fibrin deposition in CRS nasal polyp tissues and explore potential regulatory mechanisms. Methods: We analyzed the expression of genes related to the serpin family and fibrinolytic system using Gene Expression Omnibus and Next-generation sequencing data. Differentially expression genes (DEGs) analysis was used to compare control and nasal polyp tissues, followed by KEGG and Gene ontology (GO) analysis. We measured the expression and correlation of plasminogen activator-1 (PAI-1), tissue plasminogen activator (t-PA), urokinase plasminogen activator (u-PA), and urokinase plasminogen activator surface receptor (u-PAR) in CRS tissues, and evaluated the effect of eosinophils on the fibrinolytic system using a cytokine array and co-culture. Results: Nasal polyp tissues showed upregulated PAI-1, u-PA, and u-PAR expression and downregulated t-PA expression. Fibrinolytic system-related genes positively correlated with Th2 cytokines, except for t-PA. Eosinophil-derived Chitinase-3-like protein 1 (CHI3L1) increased PAI-1 expression and decreased t-PA levels in fibroblasts and epithelial cells. The inhibition of CHI3L1 suppresses these alterations. Conclusion: CHI3L1 contributes to fibrin deposition by impairing the fibrinolytic system during nasal polyp formation. The regulation of CHI3L1 expression may inhibit fibrin deposition and edema in ECRS, presenting a potential treatment for this condition.

Neutrophil migration participates in the side effect of recombinant human tissue plasminogen activator.

AIMS: Ischemic stroke remains a challenge in medical research because of the limited treatment options. Recombinant human tissue plasminogen activator (rtPA) is the primary treatment for recanalization. However, nearly 50% of the patients experience complications that result in ineffective reperfusion. The precise factors contributing to ineffective reperfusion remain unclear; however, recent studies have suggested that immune cells, notably neutrophils, may influence the outcome of rtPA thrombolysis via mechanisms such as the formation of neutrophil extracellular traps. This study aimed to explore the nonthrombolytic effects of rtPA on neutrophils and highlight their contribution to ineffective reperfusion. METHODS: We evaluated the effects of rtPA treatment on middle cerebral artery occlusion in rats. We also assessed neutrophil infiltration and activation after rtPA treatment in vitro and in vivo in a small cohort of patients with massive cerebral ischemia (MCI). RESULTS: rtPA increased neutrophil infiltration into the brain microvessels and worsened blood-brain barrier damage during ischemia. It also increased the neutrophil counts of the patients with MCI. CONCLUSION: Neutrophils play a crucial role in promoting ischemic injury and blood-brain barrier disruption, making them potential therapeutic targets.

Safety of Antithrombotic Therapy within 24 Hours after Recombinant Tissue-Plasminogen Activator Treatment for Large-Artery Atherosclerosis Stroke: Insights from Emergent PTA/CAS Cases.

BACKGROUND: Antithrombotic therapy (AT) should generally be avoided within 24 hours after recombinant tissue-plasminogen activator (rt-PA) treatment but should be considered in patients with large-artery atherosclerosis (LAA) who undergo concomitant emergent endovascular treatment (EVT). The aim of the present study was to assess the safety of AT within 24 hours after rt-PA treatment in patients with hyperacute ischemic stroke due to LAA who received concomitant EVT. METHODS: From January 2013 through July 2019, consecutive patients with acute ischemic cerebrovascular disease due to LAA who were admitted within 6 hours from symptom onset were recruited. The patients were classified into six groups based on the reperfusion treatment and early (within 24 hours) AT from rt-PA treatment. Safety outcomes were compared among the groups. RESULTS: A total of 155 patients (35 women [23%], median age 74 [IQR 66-79] years; NIHSS score 3 [1-10]) were included in the present study. Of these, 73 (47%) received no reperfusion therapy, 24 (15%) received rt-PA treatment and early AT, seven (6%) received rt-PA without early AT, 26 (17%) received EVT only, six (4%) received both rt-PA and EVT without early AT, and 19 (12%) received rt-PA and EVT with early AT. AT was administered a median of 3.9 (1.6-8.0) hours after rt-PA in patients with rt-PA+EVT with early AT. AT within 24 hours after rt-PA and EVT treatment did not increase hemorrhagic complications (p > 0.05 for all). CONCLUSION: In this retrospective analyses, early AT administration for patients with hyperacute stroke due to LAA treated with rt-PA plus EVT did not increase hemorrhagic events.

Case report: Chylopericardium secondary to dialysis catheter related jugular venous thrombosis in two dogs receiving long-term hemodialysis.

Chylopericardium is a rare entity in veterinary medicine. In this report we document the development of chylopericardium in two dogs undergoing chronic hemodialysis. An 11-year-old female spayed Labrador retriever (Case 1) presented with acute coughing and lethargy 2 months following initial dialysis catheter placement and initiation of dialysis therapy for severe azotemia. Echocardiography demonstrated severe pericardial effusion and cardiac tamponade. Pericardial fluid analysis was consistent with chylous effusion. The dog underwent a subtotal pericardiectomy with thoracic duct ligation, and a PleuralPort™ was placed. The patient continued to receive outpatient hemodialysis therapy after pericardiectomy for several months until she died acutely at home. A 4-year-old male neutered Doberman (Case 2) was being treated for 2 months with outpatient hemodialysis for management of chronic kidney disease. On presentation for the 17th hemodialysis treatment, the patient had increased respiratory rate. Echocardiography demonstrated pleural and pericardial effusions, and fluid analysis in both cavities was consistent with chylous effusion. Use of tissue plasminogen activator (TPA), clot removal and replacement of the catheter was attempted; however pleural and pericardial effusion continued. The patient was euthanized after 25 hemodialysis sessions as owners elected not to pursue more procedures. In both cases, the cause of the chylopericardium was suspected to be secondary to catheter-associated thrombosis and/or stenosis based on multiple imaging modalities. Despite use of rivaroxaban and clopidogrel concurrently in each case, the chylous effusion persisted. This case report describes clinical details of a rare complication of long-term indwelling dialysis catheters in two dogs.

Pressure ulcer development in patients treated for acute ischaemic stroke.

OBJECTIVE: The aim of this study was to determine the incidence of pressure ulcers (PUs) in patients treated for acute ischaemic stroke (AIS) and to evaluate comorbid/confounding factors. METHOD: The study included patients treated for AIS who were divided into three treatment groups: those receiving intravenous tissue plasminogen activator therapy (tPA); patients receiving mechanical thrombectomy (MT); and those receiving both tPA and MT. PUs were classified according to the international classification system and factors that may influence their development were investigated. RESULTS: A total of 242 patients were included in this study. The incidence of PUs in patients treated for AIS was 7.4%. Most PUs were located on the sacrum (3.7%), followed by the gluteus (3.3%) and trochanter (2.9%). With regards to PU classification: 29% were stage I; 34% were stage II; and the remainder were stage III. Age was not a significant factor in the development of PUs (p=0.172). Patients in the tPA group had a lower PU incidence (2.3%) than patients in the tPA+MT group (15.7%) and MT group (12.1%) (p=0.001). Patients with PUs had a longer period of hospitalisation (18.5±11.92 days) than patients without a PU (8.0±8.52 days) (p=0.000). National Institute of Health Stroke Scale (NIHSS) scores at admission were higher in patients with PUs than in patients without a PU (14.33±4.38 versus 11.08±5.68, respectively; p=0.010). The difference in presence of comorbidities between patients with and without PUs (p=0.922) and between treatment groups (p=0.677) were not statistically significant. The incidence of PUs was higher in patients requiring intensive care, but this difference was not statistically significant (p=0.089). CONCLUSION: In this study, patients treated for AIS with high NIHSS scores at admission and/or receiving MT were at higher risk for PUs, and so particular attention should be given to these patients in order to prevent PU development.

Predicting ineffective thrombolysis in acute ischemic stroke with clinical and biochemical markers.

**Ischemic stroke remains a leading cause of morbidity and mortality globally. Despite the advances in thrombolytic therapy, notably recombinant tissue plasminogen activator (rtPA), patient outcomes are highly variable. This study aims to introduce a novel predictive model, the Acute Stroke Thrombolysis Non-Responder Prediction Model (ASTN-RPM), to identify patients unlikely to benefit from rtPA within the critical early recovery window. We conducted a retrospective cohort study at Baoding No.1 Central Hospital including 709 adult patients diagnosed with acute ischemic stroke and treated with intravenous alteplase within the therapeutic time window. The ASTN-RPM was developed using Least Absolute Shrinkage and Selection Operator (LASSO) regression technique, incorporating a wide range of biomarkers and clinical parameters. Model performance was evaluated using Receiver Operating Characteristic (ROC) curves, calibration plots, and Decision Curve Analysis (DCA). ASTN-RPM effectively identified patients at high risk of poor response to thrombolysis, with an AUC of 0.909 in the training set and 0.872 in the validation set, indicating high sensitivity and specificity. Key predictors included posterior circulation stroke, high admission NIHSS scores, extended door to needle time, and certain laboratory parameters like homocysteine levels. The ASTN-RPM stands as a potential tool for refining clinical decision-making in ischemic stroke management. By anticipating thrombolytic non-response, clinicians can personalize treatment strategies, possibly improving patient outcomes and reducing the burden of ineffective interventions. Future studies are needed for external validation and to explore the incorporation of emerging biomarkers and imaging data.

Effects of Lithium Ions on tPA-Induced Hemorrhagic Transformation under Stroke.

Thrombolytic therapy with the tissue plasminogen activator (tPA) is a therapeutic option for acute ischemic stroke. However, this approach is subject to several limitations, particularly the increased risk of hemorrhagic transformation (HT). Lithium salts show neuroprotective effects in stroke, but their effects on HT mechanisms are still unknown. In our study, we use the models of photothrombosis (PT)-induced brain ischemia and oxygen-glucose deprivation (OGD) to investigate the effect of Li+ on tPA-induced changes in brain and endothelial cell cultures. We found that tPA did not affect lesion volume or exacerbate neurological deficits but disrupted the blood-brain barrier. We demonstrate that poststroke treatment with Li+ improves neurological status and increases blood-brain barrier integrity after thrombolytic therapy. Under conditions of OGD, tPA treatment increased MMP-2/9 levels in endothelial cells, and preincubation with LiCl abolished this MMP activation. Moreover, we observed the effect of Li+ on glycolysis in tPA-treated endothelial cells, which we hypothesized to have an effect on MMP expression.

Role and action mechanisms of tPA in CRH-induced apoptosis of mouse oviductal epithelial and mural granulosa cells.

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.

Variables Leading to Usage of Alteplase Versus Heparin Lock in Patients With Tunneled Catheters in Hemodialysis Care Project Centers, Saudi Arabia.

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.

Predictive value of thrombin-antithrombin III complex and tissue plasminogen activator-inhibitor complex biomarkers in assessing the severity of early-stage acute pancreatitis.

BACKGROUND AND AIM: The development of acute pancreatitis (AP) is strongly linked to blood clotting and fibrinolysis issues. Modern clinical practices now utilize advanced blood markers like thrombin-antithrombin III complex (TAT), plasmin-α2-plasmin inhibitor complex, thrombomodulin (TM), and tissue plasminogen activator-inhibitor complex (t-PAIC) to assess thrombosis risk. Our study used a highly sensitive chemiluminescence technique to measure these markers in AP patients, aiming to determine their early predictive value for AP severity. METHODS: There were 173 patients with AP, all of whom developed symptoms within 72 h; 102 individuals had onset symptoms within 48 h. The biomarkers were measured upon admission before determining the severity of AP. RESULTS: The levels of TAT, plasmin-α2-plasmin inhibitor complex, TM, and t-PAIC were significantly higher in the severe acute pancreatitis (SAP) group compared with the mild acute pancreatitis and moderate severe acute pancreatitis groups. For the patients within 72 h of onset, TAT, TM, and t-PAIC predicted the occurrence of SAP. For the patients within 48 h of onset, TAT and t-PAIC predicted the occurrence of SAP. The area under the curve (AUC) of prediction models is similar to Bedside Index for Severity in Acute Pancreatitis (BISAP) but significantly higher than C-reactive protein (P < 0.05). Notably, t-PAIC had a larger AUC than TAT, BISAP, and C-reactive protein. CONCLUSION: In the initial 48 h, plasma TAT and t-PAIC levels may predict the development of SAP. Within 72 h, plasma levels of TAT, TM, and t-PAIC may predict the development of SAP, and the TAT + TM + t-PAIC prediction model achieved a maximum AUC of 0.915, comparable to BISAP.

Biomaterial systems for evaluating the influence of ECM mechanics on anti-fibrotic therapeutic efficacy.

Cardiac fibrosis is characterized by excessive accumulation and deposition of ECM proteins. Cardiac fibrosis is commonly implicated in a variety of cardiovascular diseases, including post-myocardial infarction (MI). We have previously developed a dual-delivery nanogel therapeutic to deliver tissue plasminogen activator (tPA) and Y-27632 (a ROCK inhibitor) to address MI-associated coronary artery occlusion and downregulate cell-contractility mediated fibrotic responses. Initial in vitro studies were conducted on glass substrates. The study presented here employs the use of polyacrylamide (PA) gels and microgel thin films to mimic healthy and fibrotic cardiac tissue mechanics. Soft and stiff polyacrylamide substrates or high and low loss tangent microgel thin films were utilized to examine the influence of cell-substrate interactions on dual-loaded nanogel therapeutic efficacy. In the presence of Y-27632 containing nanogels, a reduction of fibrotic marker expression was noted on traditional PA gels mimicking healthy and fibrotic cardiac tissue mechanics. These findings differed on more physiologically relevant microgel thin films, where early treatment with the ROCK inhibitor intensified the fibrotic related responses.

Competências do enfermeiro no cuidado a pacientes com acidente vascular cerebral elegíveis à terapia trombolítica / Competencias de enfermería en el cuidado de personas con accidente cerebrovascular elegibles para terapia trombolítica / Nursing competencies in the care of patients with stroke who are eligible for thrombolytic therapy

Resumo Introdução: O acidente vascular cerebral isquêmico tem como tratamento a terapia trombolítica, aplicada ainda na fase aguda, promovendo melhora importante nas sequelas acarretadas por este agravo. Considerando a complexidade da terapia trombolítica, torna-se necessário que os enfermeiros compreendam suas competências para auxiliar no cuidado. Objetivo: Identificar evidências científicas acerca das competências do enfermeiro no cuidado a pacientes com acidente vascular cerebral elegíveis à terapia trombolítica. Metodologia: Revisão integrativa composta por seis etapas em seis etapas (elaboração da questão, busca na literatura, coleta de dados, análise, discussão e apresentação da revisão), realizada nas bases de dados MEDLINE, LILACS, BDENF, IBECS, PubMed, Scopus, Web of Science, Embase e CINAHL. A busca foi realizada entre agosto e setembro de 2022 adotando como critérios de inclusão estudos primários; gratuitos, disponíveis eletronicamente na íntegra; nos idiomas inglês, português e espanhol. Foram obtidos inicialmente 2.830 estudos, os quais passaram por uma seleção, onde foram incluídos aqueles que atendiam os critérios previamente estabelecidos. Resultados: Com base nos doze estudos incluídos nesta revisão identificaram-se competências voltadas à três atividades do cuidado: gestão do cuidado como trabalho em equipe, códigos, fluxos e protocolos, assistência ao paciente antes, durante e após a utilização da terapia trombolítica e educação em saúde para equipe, pacientes e familiares. Conclusão: Os achados desta revisão puderam evidenciar as competências do enfermeiro no cuidado aos pacientes elegíveis a terapia trombolítica, as quais perpassam diferentes áreas de atuação do enfermeiro. Para este estudo prevaleceram as competências assistências, seguida por competências gerenciais.

Resumen Introducción: El accidente cerebrovascular isquémico se trata con terapia trombolítica, aplicada incluso en la fase aguda, que promueve una mejoría significativa de las secuelas provocadas por este padecimiento. Considerando la complejidad de la terapia trombolítica, es necesario que las personas profesionales de enfermería comprendan sus competencias para ayudar en el cuidado. Objetivo: Identificar evidencias científicas sobre las competencias del personal de enfermería en el cuidado de pacientes con accidente cerebrovascular elegibles para terapia trombolítica. Metodología: Revisión integradora que consta de seis etapas (elaboración de la pregunta, búsqueda bibliográfica, recolección de datos, análisis, discusión y presentación de la revisión), realizada en las bases de dados MEDLINE, LILACS, BDENF, IBECS, PubMed, Scopus, Web of Science, Embase y CINAHL. La búsqueda se realizó entre agosto y septiembre de 2022. Los criterio de inclusión fueron: estudios primarios, gratuito, disponible electrónicamente en su totalidad, en inglés, portugués y español. Inicialmente se obtuvieron 2830 estudios, los cuales fueron sometidos a un proceso de selección, que incluyó aquellos que cumplían con los criterios previamente establecidos. Resultados: A partir de los doce estudios incluidos en esta revisión, se identificaron competencias centradas en tres actividades asistenciales: gestión del cuidado como trabajo en equipo, códigos, flujos y protocolos, atención a pacientes antes, durante y después del uso de la terapia trombolítica y educación en salud para personal, pacientes y familias. Conclusión: Los hallazgos de esta revisión pudieron resaltar las competencias de las personas profesionales en enfermería en el cuidado de personas elegibles para terapia trombolítica, que abarcan diferentes áreas de actuación del personal de enfermería. Para este estudio, prevalecieron las habilidades asistenciales, seguidas de las competencias gerenciales.

ABSTRACT Introduction: Ischemic stroke is treated with thrombolytic therapy, applied even in the acute phase, promoting a significant improvement in the after-effects caused by this condition. Considering the complexity of thrombolytic therapy, it is necessary for nurses to understand the skills required to assist in care. Objective: To identify scientific evidence about the competencies of nurses in the care of patients with stroke who are eligible for thrombolytic therapy. Methodology: An integrative review consisting of six stages (elaboration of the question, literature review, data collection, analysis, discussion, and presentation), conducted in MEDLINE, LILACS, BDENF, IBECS, PubMed, Scopus, Web of Science, Embase, and CINAHL databases. The search was carried out between August and September 2022 using primary studies as the inclusion criteria: free of charge, fully available electronically, published in English, Portuguese, or Spanish. Initially, 2.830 studies were obtained, which underwent a selection process that included only those studies that met the previously established criteria. Results: Based on the twelve studies included in this review, competencies focused on three care activities were identified: care management such as teamwork; codes; flows and protocols; patient care before, during, and after the use of thrombolytic therapy; and education health education for staff, patients, and families. Conclusion: The findings of this review highlighted the nurses' competencies in the care of patients eligible for thrombolytic therapy, which encompass different areas of the nurse's work. For this study, assistance competencies prevailed, followed by management competencies.

Dual Antiplatelet Therapy vs Alteplase in Adult Patients with Acute Minor Ischemic Stroke: A Systematic Review and Meta-Analysis.

The efficacy and safety of dual antiplatelet therapy (DAPT) relative to intravenous (IV) alteplase in patients with acute minor ischemic stroke are insufficiently established. Therefore, we aimed to perform a meta-analysis to compare DAPT with IV alteplase in patients with acute minor stroke. MEDLINE, Embase, and Cochrane were searched for studies comparing DAPT with IV alteplase in patients with minor stroke. Functional and safety outcomes in 90 days were analyzed. Statistical analysis was performed using Rstudio 4.3.1. Subanalyses were performed restricted to non-disabling minor strokes and NIHSS score ≤ 3. PROSPERO (CRD42023440986). We included five studies with a total of 6,340 patients, of whom 4,050 (63.9%) received DAPT. The follow-up period for all included studies was 90 days. There was no significant difference for individual outcomes of mRS 0-1 (OR 1.26; 95% CI 0.85-1.89; p = 0.25), mRS 0-2 (OR 0.99; 95% CI 0.69-1.43; p = 0.97), or all-cause mortality (OR 0.80; 95% CI 0.20-3.13; p = 0.75) between groups. Symptomatic intracranial hemorrhage (sICH) was significantly lower (OR 0.11; 95% CI 0.003-0.36; p < 0.001) in patients treated with DAPT compared with IV alteplase. In terms of mRS 0-1 and mRS 0-2, we found no significant difference in both subgroup analyses. We found no statistically significant difference between DAPT and IV alteplase regarding functional outcome (mRS scores of 0-1 and 0-2) or all-cause mortality at 90 days in patients with minor ischemic stroke. Additionally, DAPT was associated with a significantly lower rate of sICH.

Heterologous expression, purification and single step efficient refolding of recombinant tissue plasminogen activator (Reteplase) from E. coli.

Reteplase (recombinant plasminogen activator, rPA) is a mutant non-glycosylated tissue-type plasminogen activator (tPA) containing 355 amino acids with longer half-life and promising thrombolytic activity than its original counterpart, full length tPA. In this study, we aimed to produce and optimize the purification process of recombinant tissue-type plasminogen activator (tPA) known as Reteplase (rPA). Reteplase cDNA synthesized from total mRNA isolated from human placenta was PCR amplified, cloned into a pET-28a(+) E. coli expression vector and expressed in Rosetta-gami 2 E. coli (NovagenⓇ) host. rPA was expressed as an inclusion body in E. coli and its biological activity was achieved after single step solubilization, purification and refolding. We exploited the strategy of Slow Refolding using Gradual Dialysis (SRGD) in which a refolding buffer containing glutathione oxidized (1 mM GSSG) and glutathione reduced (3 mM GSH) and pH 9.0 was used. Using the SRGD method, we were able to successfully obtain the protein in its active form. We obtained 4.26 mg of active refolded protein from a 50 mL culture that was scaled up in a bioreactor. The purity and homogeneity of rPA was evaluated by SDS-PAGE, Western blotting and mass spectrometry. Circular dichroism spectroscopy was conducted to evaluate the refolding and stability of the refolded rPA in comparison to reference standard rPA. The thrombolytic potential of rPA was assessed by fibrin plate assay and In Vitro clot lysis assay. The presented protocol offers a viable approach for enhancing both the yield and refolding efficiency of reteplase, potentially resulting in an increase in yield.

Efficacy and safety of intravenous tenecteplase compared to alteplase before mechanical thrombectomy in acute ischemic stroke: a meta-analysis.

BACKGROUND: The benefits and risks of tenecteplase (TNK) versus alteplase (ALT) have recently been assessed in acute ischemic stroke (AIS) patients undergoing mechanical thrombectomy (MT) with diverse results. Due to its high fibrin specificity and lack of excitotoxicity, TNK may have a higher efficacy and safety profile. This study aimed to evaluate the benefits and risks of TNK compared to ALT in AIS patients prior to thrombectomy. METHODS: We systematically searched four key databases, PubMed, Embase, Web of Science and Cochrane Library until January 27, 2024 for clinical studies evaluating the effects of TNK versus ALT in patients with large vessel occlusion undergoing MT. A random-effect meta-analysis was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. RESULTS: Ten studies involving 3722 patients receiving TNK (1266 patients) or ALT (2456 patients) were included (age: 69.05 ± 14.95 years; 55.64% male). Compared to ALT-treated patients, TNK-treated patients demonstrated significantly higher rates of early recanalization (odds ratio 2.02, 95%-confidence interval 1.20-3.38, p = 0.008) without increased risk of symptomatic intracerebral hemorrhage (1.06, 0.64-1.76, p = 0.82) or intracerebral hemorrhage (1.21, 0.66-2.25, p = 0.54). TNK-treated patients showed similar rates of functional independence at 90 days (1.13, 0.87-1.46, p = 0.37) as ALT-treated patients, but lower rates of mortality within 90 days (0.65, 0.44-0.96, p = 0.03). CONCLUSION: TNK is superior to ALT in achieving early recanalization and is associated with lower mortality within 90 days in AIS patients undergoing MT. Compared with ALT, TNK does not significantly alter functional independence at 90 days, symptomatic intracerebral hemorrhage or intracerebral hemorrhage.

Delayed onset septic pelvic thrombophlebitis treated by tissue-plasminogen activator following initial treatment for massive right ovarian vein thrombosis and methicillin-resistant Staphylococcus aureus bacteremia: A case report.

Septic pelvic thrombophlebitis (SPT) is a rare condition that forms thrombosis in the pelvic veins, typically the ovarian veins, with subsequent infection and inflammation. We present a case of right ovarian vein thrombosis (ROVT), methicillin-resistant Staphylococcus aureus (MRSA) bacteremia, and delayed onset of SPT symptoms, requiring tissue-plasminogen activator. A 40-year-old woman, G3P2, at 38 weeks' gestation, was admitted with a fever of 39°C. She had cervical insufficiency and had been often on bed rest. Blood culture revealed MRSA and computed tomography revealed a large ROVT. She received vancomycin and direct oral anticoagulant, and her fever resolved by day 3. On day 16, fever recurred with severe pain over the ROVT. Second computed tomography showed thickening of venous wall with enhancement around ROVT, consistent with SPT. Since pain and fever gradually exacerbated despite treatment with DOAC and antimicrobials, she was started on heparin and tissue plasminogen activator on days 23 and 25, respectively. Along with recanalization on the thrombosis by day 29, fever and abdominal pain resolved. We experienced a case of delayed onset SPT associated with MRSA bacteremia and a large ROVT. MRSA bacteremia might cause the originally existing ROVT to become an infection source, resulting in SPT with recurrent symptoms and long-term treatment. Early and strict anticoagulation is crucial in cases with a large thrombosis and bacteremia, due to the high risk of progression to SPT. This case highlights the importance of recanalization for the treatment of SPT and usefulness of administration of tissue-plasminogen activator for the massive thrombosis.

Plasminogen Degradation by Neutrophil Elastase in Pleural Infection, Not High Plasminogen Activator Inhibitor 1, Is the Cause of Intrapleural Lytic Failure.

BACKGROUND: Complex pleural space infections often require treatment with multiple doses of intrapleural tissue plasminogen activator (tPA) and deoxyribonuclease, with treatment failure frequently necessitating surgery. Pleural infections are rich in neutrophils, and neutrophil elastase degrades plasminogen, the target substrate of tPA, that is required to generate fibrinolysis. We hypothesized that pleural fluid from patients with pleural space infection would show high elastase activity, evidence of inflammatory plasminogen degradation, and low fibrinolytic potential in response to tPA that could be rescued with plasminogen supplementation. RESEARCH QUESTION: Does neutrophil elastase degradation of plasminogen contribute to intrapleural fibrinolytic failure? STUDY DESIGN AND METHODS: We obtained infected pleural fluid and circulating plasma from hospitalized adults (n = 10) with institutional review board approval from a randomized trial evaluating intrapleural fibrinolytics vs surgery for initial management of pleural space infection. Samples were collected before the intervention and on days 1, 2, and 3 after the intervention. Activity assays, enzyme-linked immunosorbent assays, and Western blot analysis were performed, and turbidimetric measurements of fibrinolysis were obtained from pleural fluid with and without exogenous plasminogen supplementation. Results are reported as median (interquartile range) or number (percentage) as appropriate, with an α value of 0.05. RESULTS: Pleural fluid elastase activity was more than fourfold higher (P = .02) and plasminogen antigen levels were more than threefold lower (P = .04) than their corresponding plasma values. Pleural fluid Western blot analysis demonstrated abundant plasminogen degradation fragments consistent with elastase degradation patterns. We found that plasminogen activator inhibitor 1 (PAI-1), the native tPA inhibitor, showed high antigen levels before the intervention, but the overwhelming majority of this PAI-1 (82%) was not active (P = .003), and all PAI-1 activity was lost by day 2 after the intervention in patients receiving intrapleural tPA and deoxyribonuclease. Finally, using turbidity clot lysis assays, we found that the pleural fluid of 9 of 10 patients was unable to generate a significant fibrinolytic response when challenged with tPA and that plasminogen supplementation rescued fibrinolysis in all patients. INTERPRETATION: Inflammatory plasminogen deficiency, not high PAI-1 activity, is a significant contributor to intrapleural fibrinolytic failure. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03583931; URL: www. CLINICALTRIALS: gov.

The prognostic value of combined uric acid and neutrophil-to-lymphocyte ratio in acute ischemic stroke patients treated with intravenous thrombolysis.

BACKGROUND: Serum uric acid (UA) and the neutrophil-to-lymphocyte ratio (NLR) have been reported to be associated with outcomes in acute ischemic stroke (AIS). However, whether UA is related to the prognosis of AIS patients undergoing intravenous thrombolysis (IVT) remains inconclusive. We sought to explore the combined effect of UA and NLR on the prognosis of AIS treated with IVT. METHODS: A total of 555 AIS patients receiving IVT treatment were enrolled. Patients were categorized into four groups according to the levels of UA and NLR: LNNU (low NLR and normal UA), LNHU (low NLR and high UA), HNNU (high NLR and normal UA), and HNHU (high NLR and high UA). Multivariable logistic regression analysis was used to evaluate the value of serum UA level and NLR in predicting prognosis. The primary outcomes were major disability (modified Rankin scale (mRS) score 3-5) and death within 3 months. RESULTS: After multivariate adjustment, a high NLR (≥ 3.94) increased the risk of 3-month death or major disability (OR, 2.23; 95% CI, 1.42 to 3.55, p < 0.001). However, there was no statistically significant association between a high UA level (≥ 313.00 µmol/L) and clinical outcome. HNHU was associated with a 5.09-fold increase in the risk of death (OR, 5.09; 95% CI, 1.31-19.83; P value = 0.019) and a 1.98-fold increase in the risk of major disability (OR, 1.98; 95% CI 1.07-3.68; P value = 0.030) in comparison to LNNU. CONCLUSIONS: High serum UA levels combined with high NLR were independently associated with 3-month death and major disability in AIS patients after IVT.