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Single nucleotide variations in ZBTB46 are associated with post-thrombolytic parenchymal haematoma.
Carrera, C, Cárcel-Márquez, J, Cullell, N, Torres-Águila, N, Muiño, E, Castillo, J, Sobrino, T, Campos, F, Rodríguez-Castro, E, Llucià-Carol, L, et al
Brain : a journal of neurology. 2021;(8):2416-2426
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Abstract
Haemorrhagic transformation is a complication of recombinant tissue-plasminogen activator treatment. The most severe form, parenchymal haematoma, can result in neurological deterioration, disability, and death. Our objective was to identify single nucleotide variations associated with a risk of parenchymal haematoma following thrombolytic therapy in patients with acute ischaemic stroke. A fixed-effect genome-wide meta-analysis was performed combining two-stage genome-wide association studies (n = 1904). The discovery stage (three cohorts) comprised 1324 ischaemic stroke individuals, 5.4% of whom had a parenchymal haematoma. Genetic variants yielding a P-value < 0.05 1 × 10-5 were analysed in the validation stage (six cohorts), formed by 580 ischaemic stroke patients with 12.1% haemorrhagic events. All participants received recombinant tissue-plasminogen activator; cases were parenchymal haematoma type 1 or 2 as defined by the European Cooperative Acute Stroke Study (ECASS) criteria. Genome-wide significant findings (P < 5 × 10-8) were characterized by in silico functional annotation, gene expression, and DNA regulatory elements. We analysed 7 989 272 single nucleotide polymorphisms and identified a genome-wide association locus on chromosome 20 in the discovery cohort; functional annotation indicated that the ZBTB46 gene was driving the association for chromosome 20. The top single nucleotide polymorphism was rs76484331 in the ZBTB46 gene [P = 2.49 × 10-8; odds ratio (OR): 11.21; 95% confidence interval (CI): 4.82-26.55]. In the replication cohort (n = 580), the rs76484331 polymorphism was associated with parenchymal haematoma (P = 0.01), and the overall association after meta-analysis increased (P = 1.61 × 10-8; OR: 5.84; 95% CI: 3.16-10.76). ZBTB46 codes the zinc finger and BTB domain-containing protein 46 that acts as a transcription factor. In silico studies indicated that ZBTB46 is expressed in brain tissue by neurons and endothelial cells. Moreover, rs76484331 interacts with the promoter sites located at 20q13. In conclusion, we identified single nucleotide variants in the ZBTB46 gene associated with a higher risk of parenchymal haematoma following recombinant tissue-plasminogen activator treatment.
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Comparative analysis of fibrinolytic properties of Alteplase, Tenecteplase and Urokinase in an in vitro clot model of intracerebral haemorrhage.
Keric, N, Döbel, M, Krenzlin, H, Kurz, E, Tanyildizi, Y, Heimann, A, König, J, Kempski, O, Ringel, F, Masomi-Bornwasser, J
Journal of stroke and cerebrovascular diseases : the official journal of National Stroke Association. 2020;(9):105073
Abstract
OBJECTIVE Hematoma lysis with recombinant tissue plasminogen activator (rtPA) has emerged as an alternative therapy for spontaneous intracerebral and intraventricular haemorrhage (ICH and IVH). However, the MISTIE III and CLEAR III trial failed to show significant improvement of favourable outcomes. Besides experimental and clinical trials revealed neurotoxic effects of rtPA. The demand for optimization of fibrinolytic therapy persists. Herein, we used our recently devised clot model of ICH to systematically analyse fibrinolytic properties of rtPA, tenecteplase and urokinase. METHODS In vitro clots of human blood (size: 25 ml and 50 ml; age: 1.5 tenecteplase, 24 tenecteplase and 48 tenecteplase) were produced and equipped with a catheter into the clot core for drug delivery and drainage. Various doses of tenecteplase and urokinase with different treatment periods were examined (overall 117 clots), assessing the optimal dose and treatment time of these fibrinolytics. Clots were weighed before and at the end of treatment. These results were compared with clots treated with 1 mg rtPA or with 0.9% sodium chloride solution. RESULTS The optimal treatment scheme of tenecteplase was found to be 100 IU with an incubation time of 30 min, for urokinase it was 50 000 IU with an incubation time of 20 min. The relative clot end weight of tenecteplase and urokinase (31.3±11.9%, 34.8 ±7.7%) was comparable to rtPA (36.7±10.7%). Larger clots were more effectively treated with tenecteplase compared to the control group (P=0.0013). urokinase and tenecteplase had similar lysis rates in aged clots and 90 min clots. One and two repetitive treatments with tenecteplase were as effective as two and three cycles of urokinase. CONCLUSIONS In our in vitro clot model we could determine optimal treatment regimens of tenecteplase (100 IU, 30 min) and urokinase (50 000 IU, 20 min). Urokinase and tenecteplase were comparable in their fibrinolytic potential compared to 1mg rtPA in small clots and showed an effective lysis in aged clots. tenecteplase was more effective in larger clots.
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Efficient refolding of recombinant reteplase expressed in Escherichia coli strains using response surface methodology.
Fathi-Roudsari, M, Maghsoudi, A, Maghsoudi, N, Niazi, S, Soleiman, M
International journal of biological macromolecules. 2020;:1321-1327
Abstract
Reteplase is a deleted variant of human tissue plasminogen activator with a complex structure containing nine disulfide bonds. Reteplase is expressed as inclusion bodies in Escherichia coli and needs the additional step of refolding for activation. In this study an experimental design was performed to find the optimal refolding condition for reteplase. The influence of 14 chemical additives was assessed by one factor at a time method and then Taguchi design followed by response surface methodology was employed to find compounds with most significant effects on reteplase refolding and their optimum concentration. We found that 0.13 M histidine, 1.64 M methionine, 0.33 M cysteine, and 0.34 M arginine in addition to the GSH/GSSG is the optimal condition for refolding of reteplase. We also investigated the refolding yield for inclusion bodies obtained from different E. coli strains and found that BL21 (DE3) has the best recovery yield in comparison to Rosetta-gami and Shuffle T7.
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Lysis Timer: a new sensitive tool to diagnose hyperfibrinolysis in liver transplantation.
Roullet, S, Labrouche, S, Mouton, C, Quinart, A, Nouette-Gaulain, K, Laurent, C, Freyburger, G
Journal of clinical pathology. 2019;(1):58-65
Abstract
AIMS: Diagnosis of hyperfibrinolysis in orthotopic liver transplantation (OLT) remains challenging. Euglobulin clot lysis time (ECLT) is not adapted to clinical situations. ROTEM is specific but seldom sensitive to hyperfibrinolysis. The Lysis Timer assesses 'Global Fibrinolytic Capacity' in citrated plasma (GFC/LT). GFC/LT associates reagents for in vitro triggering of the clot (thrombin and calcium) and its lysis (tissue-plasminogenactivator (t-PA)), turbidity signal acquisition by the Lysis Timer, and dedicated software converting the digital signal into an optical curve. A visual check of the curves was systematic to ascertain the lysis time values calculated by the software. The primary aim of this prospective observational study was to evaluate the ability of GFC/LT to recognise hyperfibrinolysis during OLT. The secondary aim was to compare its results with ROTEM maximum lysis (EXTEM ML) and with standard laboratory tests. METHODS Thirty consecutive adult patients undergoing OLT were included (NCT03012633). Standard laboratory tests, ROTEM, GFC/LT, ECLT and fibrinolysis parameters were assayed at five sample times. RESULTS GFC/LT was correlated with ECLT, plasmin activator inhibitor 1 antigen and activity and t-PA activity (r=0.490, 0.681, 0.643 and -0.359, respectively). Hyperfibrinolysis was defined as ECLT ≤60 min. Receiver operating characteristic curve analysis showed that GFC/LT with a threshold of 31 min detected hyperfibrinolysis with a sensitivity of 0.88 (95% CI 0.73 to 0.96), a specificity of 0.68 (95% CI 0.56 to 0.78) and an area under the curve (AUC) of 0.85 (95% CI 0.74 to 0.94). EXTEM ML >12% did not detect hyperfibrinolysis (sensitivity 0.38 (95% CI 0.24 to 0.55), specificity 0.95 (95% CI 0.86 to 0.99) and AUC 0.60 (95% CI 0.46 to 0.75)). CONCLUSIONS GFC/LT recognised hyperfibrinolysis during OLT with a significant agreement with the other tests of fibrinolysis. TRIAL REGISTRATION NUMBER NCT03012633.
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Leaf-Inspired Authentically Complex Microvascular Networks for Deciphering Biological Transport Process.
Miali, ME, Colasuonno, M, Surdo, S, Palomba, R, Pereira, R, Rondanina, E, Diaspro, A, Pascazio, G, Decuzzi, P
ACS applied materials & interfaces. 2019;(35):31627-31637
Abstract
The vascular transport of molecules, cells, and nanoconstructs is a fundamental biophysical process impacting tissue regeneration, delivery of nutrients and therapeutic agents, and the response of the immune system to external pathogens. This process is often studied in single-channel microfluidic devices lacking the complex tridimensional organization of vascular networks. Here, soft lithography is employed to replicate the vein system of a Hedera elix leaf on a polydimethilsiloxane (PDMS) template. The replica is then sealed and connected to an external pumping system to realize an authentically complex microvascular network. This satisfies energy minimization criteria by Murray's law and comprises a network of channels ranging in size from capillaries (∼50 μm) to large arterioles and venules (∼400 μm). Micro-PIV (micro-particle image velocimetry) analysis is employed to characterize flow conditions in terms of streamlines, fluid velocity, and flow rates. To demonstrate the ability to reproduce physiologically relevant transport processes, two different applications are demonstrated: vascular deposition of tumor cells and lysis of blood clots. To this end, conditions are identified to culture cells within the microvasculature and realize a confluent endothelial monolayer. Then, the vascular deposition of circulating breast (MDA-MB 231) cancer cells is documented throughout the network under physiologically relevant flow conditions. Firm cell adhesion mostly occurs in channels with low mean blood velocity. As a second application, blood clots are formed within the chip by mixing whole blood with a thrombin solution. After demonstrating the blood clot stability, tissue plasminogen activator (tPA) and tPA-carrying nanoconstructs (tPA-DPNs) are employed as thrombolytics. In agreement with previous data, clot dissolution is equally induced by tPA and tPA-DPNs. The proposed leaf-inspired chip can be efficiently used to study a variety of vascular transport processes in complex microvascular networks, where geometry and flow conditions can be modulated and monitored throughout the experimental campaign.
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Prophylactic rtPA in the Prevention of Line-associated Thrombosis and Infection in Short Bowel Syndrome.
Malec, LM, Cooper, J, Rudolph, J, Michaels, MG, Ragni, MV
Journal of pediatric gastroenterology and nutrition. 2018;(6):972-975
Abstract
BACKGROUND Central venous access devices (CVADs) are essential for total parenteral nutrition administration in patients with short bowel syndrome (SBS). They are, however, fraught with complications including infection and venous thromboembolism (VTE), which increases associated morbidity and mortality in this population. There is evidence linking the development of CVAD-associated thrombosis and line-related infection. Thus, it has been postulated that prevention of catheter-related clot formation could minimize the risk of infection originating from the catheter. Recombinant tissue plasminogen activator (rtPA, alteplase), lyses clots by binding plasmin-bound fibrin in a clot and cleaving plasminogen to plasmin; moreover, it is widely used to clear occluded CVADs. METHODS Prophylactic rtPA lock therapy in children with SBS was evaluated as a single site pilot study to minimize line-associated VTE, infection, need for line replacement, and hospitalization at the Children's Hospital of Pittsburgh of University of Pittsburgh Medical Center. rtPA lock therapy was administered by parents/caregivers on a weekly basis over a 6-month time period in place of heparin lock therapy. Comparisons were made between line-associated complications in the cohort in the 6 months before study versus during the study period. RESULTS Six out of 8 subjects completed the study over a 1-year time period. As a group, subjects experienced a significant decrease in the number of line-associated bloodstream infections from a mean of 1.9 infections in the 6 months before the study to a mean of 0.5 infections (P = 0.025). There was no change in the need for line replacement amongst subjects while on study. The primary outcome of VTE was not found in the cohort, and it is unclear whether rtPA lock therapy contributed to the lack of thrombosis development. Given the success of rtPA in this pilot study in reducing bloodstream infections, further investigation or rtPA lock therapy in patients with SBS is warranted.
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Endurance exercise per se reduces the cardiovascular risk marker t-PA antigen in healthy, younger, overweight men.
Bladbjerg, EM, Skov, J, Nordby, P, Stallknecht, B
Thrombosis research. 2017;:69-73
Abstract
INTRODUCTION The cardiovascular risk marker tissue plasminogen activator antigen (t-PA:Ag) can be reduced by long-term exercise interventions, but it is unknown, whether this is due to the weight loss induced by physical activity or due to the physical activity per se. MATERIALS AND METHODS This was tested in 60 healthy, younger (20-40years), overweight (BMI: 25-30kg/m2) men randomly assigned to 12weeks of intervention in one of four groups: training (T); energy-reduced diet (D); training and increased diet (T-iD); sedentary lifestyle and unchanged diet (controls, C). Fasting blood samples were obtained before and after 12weeks of intervention and analyzed for plasma t-PA:Ag. RESULTS Body weight was reduced in groups T and D. We observed a decrease in t-PA:Ag from baseline to 12weeks in all three exercise and diet intervention groups, and no change in the control group. A between-group difference in t-PA:Ag was observed at 12weeks (p=0.001), and this was due to lower values in T (p=0.0005), D (p=0.005) and T-iD (p=0.009) compared with the control group. Total body fat mass was reduced in all three exercise groups, and we observed a positive correlation between changes in t-PA:Ag and changes in intra-abdominal and subcutaneous adipose tissue volume. CONCLUSIONS Our results demonstrate that t-PA:Ag was reduced in all three intervention groups. This suggests that 12weeks of endurance training per se, irrespective of concomitant weight loss, beneficially affects cardiovascular risk in healthy, younger, overweight men.
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Thrombolytic removal of intraventricular haemorrhage in treatment of severe stroke: results of the randomised, multicentre, multiregion, placebo-controlled CLEAR III trial.
Hanley, DF, Lane, K, McBee, N, Ziai, W, Tuhrim, S, Lees, KR, Dawson, J, Gandhi, D, Ullman, N, Mould, WA, et al
Lancet (London, England). 2017;(10069):603-611
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Abstract
BACKGROUND Intraventricular haemorrhage is a subtype of intracerebral haemorrhage, with 50% mortality and serious disability for survivors. We aimed to test whether attempting to remove intraventricular haemorrhage with alteplase versus saline irrigation improved functional outcome. METHODS In this randomised, double-blinded, placebo-controlled, multiregional trial (CLEAR III), participants with a routinely placed extraventricular drain, in the intensive care unit with stable, non-traumatic intracerebral haemorrhage volume less than 30 mL, intraventricular haemorrhage obstructing the 3rd or 4th ventricles, and no underlying pathology were adaptively randomly assigned (1:1), via a web-based system to receive up to 12 doses, 8 h apart of 1 mg of alteplase or 0·9% saline via the extraventricular drain. The treating physician, clinical research staff, and participants were masked to treatment assignment. CT scans were obtained every 24 h throughout dosing. The primary efficacy outcome was good functional outcome, defined as a modified Rankin Scale score (mRS) of 3 or less at 180 days per central adjudication by blinded evaluators. This study is registered with ClinicalTrials.gov, NCT00784134. FINDINGS Between Sept 18, 2009, and Jan 13, 2015, 500 patients were randomised: 249 to the alteplase group and 251 to the saline group. 180-day follow-up data were available for analysis from 246 of 249 participants in the alteplase group and 245 of 251 participants in the placebo group. The primary efficacy outcome was similar in each group (good outcome in alteplase group 48% vs saline 45%; risk ratio [RR] 1·06 [95% CI 0·88-1·28; p=0·554]). A difference of 3·5% (RR 1·08 [95% CI 0·90-1·29], p=0·420) was found after adjustment for intraventricular haemorrhage size and thalamic intracerebral haemorrhage. At 180 days, the treatment group had lower case fatality (46 [18%] vs saline 73 [29%], hazard ratio 0·60 [95% CI 0·41-0·86], p=0·006), but a greater proportion with mRS 5 (42 [17%] vs 21 [9%]; RR 1·99 [95% CI 1·22-3·26], p=0·007). Ventriculitis (17 [7%] alteplase vs 31 [12%] saline; RR 0·55 [95% CI 0·31-0·97], p=0·048) and serious adverse events (114 [46%] alteplase vs 151 [60%] saline; RR 0·76 [95% CI 0·64-0·90], p=0·002) were less frequent with alteplase treatment. Symptomatic bleeding (six [2%] in the alteplase group vs five [2%] in the saline group; RR 1·21 [95% CI 0·37-3·91], p=0·771) was similar. INTERPRETATION In patients with intraventricular haemorrhage and a routine extraventricular drain, irrigation with alteplase did not substantially improve functional outcomes at the mRS 3 cutoff compared with irrigation with saline. Protocol-based use of alteplase with extraventricular drain seems safe. Future investigation is needed to determine whether a greater frequency of complete intraventricular haemorrhage removal via alteplase produces gains in functional status. FUNDING National Institute of Neurological Disorders and Stroke.
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Sodium Tanshinone IIA Sulfonate Enhances Effectiveness Rt-PA Treatment in Acute Ischemic Stroke Patients Associated with Ameliorating Blood-Brain Barrier Damage.
Ji, B, Zhou, F, Han, L, Yang, J, Fan, H, Li, S, Li, J, Zhang, X, Wang, X, Chen, X, et al
Translational stroke research. 2017;(4):334-340
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Abstract
Treatment with sodium tanshinone IIA sulfonate (STS) may ameliorate blood-brain barrier (BBB) damage in acute ischemic stroke patients receiving recombinant tissue plasminogen activator (rt-PA) thrombolysis and improve stroke patients' outcome. This randomized, single-center, placebo-controlled clinical trial investigated the potential effects and underlying mechanisms of STS. Forty-two acute ischemic stroke patients receiving intravenous rt-PA thrombolysis were randomized to intravenous administration either with STS (60 mg/day) (n = 21) or with equivalent volume of saline as a placebo (n = 21) after randomization for 10 days. Clinical outcomes, computer tomography perfusion (CTP) imaging with permeability-surface area product (PS) maps and serum levels of BBB damage biomarkers, were compared between the two groups. The percentage of patients with excellent functional outcome indicated by a 90-day mRS ≤1 was significantly higher in the STS group than in the placebo group (p = 0.028). For patients with CTP imaging (n = 30), PS in the ipsilateral lesion (p = 0.034) and relative PS (p = 0.013) were significantly lower in the STS group than that in placebo. STS-treated patients also had lower levels of matrix metalloproteinase (MMP)-9 (p = 0.036) and claudin-5 (p = 0.026), but higher levels of tissue inhibitor of metalloproteinase (TIMP)-1 (p = 0.040) than those in the placebo group. Post-stroke STS treatment could improve neurologic functional outcomes for acute ischemic stroke patients following rt-PA treatment by reducing BBB leakage and damage, which might be mechanistically associated with MMP-9 inhibition.
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Resveratrol improves delayed r-tPA treatment outcome by reducing MMPs.
Chen, J, Bai, Q, Zhao, Z, Sui, H, Xie, X
Acta neurologica Scandinavica. 2016;(1):54-60
Abstract
OBJECTIVES Although recombinant tissue plasminogen activator (r-tPA) is currently the most effective treatment for brain ischemic stroke, the 3-h narrow therapeutic windows severely limits its clinical efficacy. We aim to investigate the effect of resveratrol on improving treatment outcomes of delayed r-tPA administration. MATERIALS & METHODS Patients were randomly divided according to their onset-to-treatment time (OTT), as early OTT or delayed OTT. Then, they were either treated with r-tPA + placebo or with r-tPA + resveratrol. Twenty-four hours after the treatment, outcomes were assessed with NIH stroke scale (NIHSS), and plasma levels of MMP-2 and MMP-9 were also examined with ELISA. RESULTS In patients receiving delayed r-tPA treatment, co-administration of resveratrol significantly improves their treatment outcomes compared with those receiving placebo, as indicated by improved NIHSS scores. This improved outcome was be caused by resveratrol-induced reduction in plasma levels of both matrix metalloproteinase (MMP)-2 and MMP-9, as a positive correlation was observed between reductions in both MMPs and patient NIHSS scores. CONCLUSIONS Resveratrol could be potentially administered as an adjuvant with r-tPA treatment, which extends the clinical therapeutic window of r-tPA, therefore improving the outcome of patients receiving late stroke treatment.