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Haj Mohamad Ebrahim Ketabforoush A, Hosseinpour A, Habibi MA, Ariaei A, Farajollahi M, Chegini R, Mirzaasgari Z. Optimizing Acute Ischemic Stroke Outcomes: The Role of Tenecteplase Before Mechanical Thrombectomy. Clin Ther 2024:S0149-2918(24)00223-6. [PMID: 39266330 DOI: 10.1016/j.clinthera.2024.08.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2024] [Revised: 08/09/2024] [Accepted: 08/13/2024] [Indexed: 09/14/2024]
Abstract
PURPOSE Acute ischemic stroke (AIS) is a life-threatening condition demanding prompt reperfusion to salvage brain tissue. Thrombolytic drugs, like tenecteplase (TNK), offer clot dissolution, but time constraints and contraindications limit their use. Mechanical thrombectomy (MT) revolutionized AIS treatment, especially for large vessel occlusions (LVO). Recent evidence suggests that administering TNK before MT improves recanalization and outcomes, challenging the dominance of alteplase. METHODS Relevant articles focusing on TNK before MT were retrieved from PubMed, Scopus, and Web of Science, looking for randomized controlled trials (RCT), clinical trials, and meta-analyses in humans until 2024. FINDINGS TNK, a genetically engineered thrombolytic, exhibits superior fibrin specificity and a longer half-life than alteplase. Clinical trials comparing TNK and alteplase before MT showcase enhanced recanalization, functional outcomes, and safety with TNK. Advanced neuroimaging aids patient selection, though its cost-effectiveness warrants consideration. Dosing studies favor a 0.25 mg/kg dose for efficacy and reduced complications. Clinical guidelines from various associations acknowledge TNK's potential as an alteplase alternative for AIS treatment, particularly for LVOs eligible for thrombectomy. IMPLICATIONS In conclusion, TNK emerges as a promising option for bridging therapy in AIS, displaying efficacy and safety benefits, especially when administered before MT. Its fibrin specificity, longer half-life, and potential for improved outcomes position TNK as a viable alternative to alteplase, potentially transforming the landscape of AIS treatment strategies. While limitations like small sample sizes and variations in protocols exist, future research should focus on large-scale RCT, subgroup analyses, and cost-effectiveness evaluations to further elucidate TNK's role in optimizing AIS management.
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Affiliation(s)
| | - Ali Hosseinpour
- Department of Neurology, Clinical Research Development Unit (CRDU) of Shahid Rajaei Hospital, Alborz University of Medical Sciences, Karaj, Iran
| | - Mohamad Amin Habibi
- Clinical Research Development Center, Shahid Beheshti Hospital, Qom University of Medical Sciences, Qom, Iran
| | - Armin Ariaei
- School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | | | - Rojin Chegini
- Metabolic liver disease research center, Isfahan University of medical sciences, Isfahan, Iran
| | - Zahra Mirzaasgari
- Department of Neurology, Firouzgar Hospital, Iran University of Medical Sciences, Tehran, Iran.
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2
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Rashedi S, Greason CM, Sadeghipour P, Talasaz AH, O'Donoghue ML, Jimenez D, Monreal M, Anderson CD, Elkind MSV, Kreuziger LMB, Lang IM, Goldhaber SZ, Konstantinides SV, Piazza G, Krumholz HM, Braunwald E, Bikdeli B. Fibrinolytic Agents in Thromboembolic Diseases: Historical Perspectives and Approved Indications. Semin Thromb Hemost 2024; 50:773-789. [PMID: 38428841 DOI: 10.1055/s-0044-1781451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2024]
Abstract
Fibrinolytic agents catalyze the conversion of the inactive proenzyme plasminogen into the active protease plasmin, degrading fibrin within the thrombus and recanalizing occluded vessels. The history of these medications dates to the discovery of the first fibrinolytic compound, streptokinase, from bacterial cultures in 1933. Over time, researchers identified two other plasminogen activators in human samples, namely urokinase and tissue plasminogen activator (tPA). Subsequently, tPA was cloned using recombinant DNA methods to produce alteplase. Several additional derivatives of tPA, such as tenecteplase and reteplase, were developed to extend the plasma half-life of tPA. Over the past decades, fibrinolytic medications have been widely used to manage patients with venous and arterial thromboembolic events. Currently, alteplase is approved by the U.S. Food and Drug Administration (FDA) for use in patients with pulmonary embolism with hemodynamic compromise, ST-segment elevation myocardial infarction (STEMI), acute ischemic stroke, and central venous access device occlusion. Reteplase and tenecteplase have also received FDA approval for treating patients with STEMI. This review provides an overview of the historical background related to fibrinolytic agents and briefly summarizes their approved indications across various thromboembolic diseases.
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Affiliation(s)
- Sina Rashedi
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Christie M Greason
- Thrombosis Research Group, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Parham Sadeghipour
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
- Clinical Trial Center, Rajaie Cardiovascular, Medical, and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Azita H Talasaz
- Department of Pharmacotherapy and Outcomes Sciences, Virginia Commonwealth University, Richmond, Virginia
- Department of Pharmacy Practice, Arnold and Marie Schwartz College of Pharmacy and Health Sciences, Long Island University, New York, New York
- Department of Pharmacy, New York-Presbyterian Hospital Columbia University Medical Center, New York, New York
| | - Michelle L O'Donoghue
- Division of Cardiovascular Medicine, TIMI Study Group, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - David Jimenez
- Respiratory Department, Hospital Ramón y Cajal (IRYCIS), Madrid, Spain
- Medicine Department, Universidad de Alcalá (IRYCIS), Madrid, Spain
- CIBER Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Manuel Monreal
- Department of Internal Medicine, Hospital Germans Trias i Pujol, Badalona, Spain
- Universidad Catolica de Murcia, Murcia, Spain
| | - Christopher D Anderson
- Program in Medical and Population Genetics, Broad Institute of Harvard and the Massachusetts Institute of Technology, Boston, Massachusetts
- McCance Center for Brain Health, Massachusetts General Hospital, Boston, Massachusetts
- Department of Neurology, Brigham and Women's Hospital, Boston, Massachusetts
| | - Mitchell S V Elkind
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York
- Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York
| | - Lisa M Baumann Kreuziger
- Medical College of Wisconsin, Milwaukee, Wisconsin
- Blood Research Institute, Versiti, Milwaukee, Wisconsin
| | - Irene M Lang
- Department of Internal Medicine II, Cardiology and Center of Cardiovascular Medicine, Medical University of Vienna, Vienna, Austria
| | - Samuel Z Goldhaber
- Thrombosis Research Group, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
- Cardiovascular Medicine Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Stavros V Konstantinides
- Center for Thrombosis and Haemostasis, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
- Department of Cardiology, Democritus University of Thrace, Alexandroupolis, Greece
| | - Gregory Piazza
- Thrombosis Research Group, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
- Cardiovascular Medicine Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Harlan M Krumholz
- YNHH/Yale Center for Outcomes Research and Evaluation (CORE), New Haven, Connecticut
- Section of Cardiovascular Medicine, Yale School of Medicine, New Haven, Connecticut
- Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut
| | - Eugene Braunwald
- Division of Cardiovascular Medicine, TIMI Study Group, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
- Cardiovascular Medicine Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Behnood Bikdeli
- Thrombosis Research Group, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
- Cardiovascular Medicine Division, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
- YNHH/Yale Center for Outcomes Research and Evaluation (CORE), New Haven, Connecticut
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3
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Wang L, Hao M, Wu N, Wu S, Fisher M, Xiong Y. Comprehensive Review of Tenecteplase for Thrombolysis in Acute Ischemic Stroke. J Am Heart Assoc 2024; 13:e031692. [PMID: 38686848 PMCID: PMC11179942 DOI: 10.1161/jaha.123.031692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2023] [Accepted: 02/20/2024] [Indexed: 05/02/2024]
Abstract
Although intravenous thrombolysis with alteplase remains the primary treatment for acute ischemic stroke, tenecteplase has shown potential advantages over alteplase. Animal studies have demonstrated the favorable pharmacokinetics and pharmacodynamics of tenecteplase. Moreover, it is easier to administer. Clinical trials have demonstrated that tenecteplase is not inferior to alteplase and may even be superior in cases of acute ischemic stroke with large vessel occlusion. Current evidence supports the time and cost benefits of tenecteplase, suggesting that it could potentially replace alteplase as the main option for thrombolytic therapy, especially in patients with large vessel occlusion.
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Affiliation(s)
- Liyuan Wang
- Department of Neurology, Beijing Tiantan Hospital Capital Medical University Beijing China
| | - Manjun Hao
- Department of Neurology, Beijing Tiantan Hospital Capital Medical University Beijing China
| | - Na Wu
- Department of Neurology, Beijing Tiantan Hospital Capital Medical University Beijing China
| | - Shuangzhe Wu
- Chinese Institute for Brain Research Beijing China
| | - Marc Fisher
- Department of Neurology, Beth Israel Deaconess Medical Center Harvard Medical School Boston MA USA
| | - Yunyun Xiong
- Department of Neurology, Beijing Tiantan Hospital Capital Medical University Beijing China
- Chinese Institute for Brain Research Beijing China
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4
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Bindal P, Kumar V, Kapil L, Singh C, Singh A. Therapeutic management of ischemic stroke. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2024; 397:2651-2679. [PMID: 37966570 DOI: 10.1007/s00210-023-02804-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 10/19/2023] [Indexed: 11/16/2023]
Abstract
Stroke is the third leading cause of years lost due to disability and the second-largest cause of mortality worldwide. Most occurrences of stroke are brought on by the sudden occlusion of an artery (ischemic stroke), but sometimes they are brought on by bleeding into brain tissue after a blood vessel has ruptured (hemorrhagic stroke). Alteplase is the only therapy the American Food and Drug Administration has approved for ischemic stroke under the thrombolysis category. Current views as well as relevant clinical research on the diagnosis, assessment, and management of stroke are reviewed to suggest appropriate treatment strategies. We searched PubMed and Google Scholar for the available therapeutic regimes in the past, present, and future. With the advent of endovascular therapy in 2015 and intravenous thrombolysis in 1995, the therapeutic options for ischemic stroke have expanded significantly. A novel approach such as vagus nerve stimulation could be life-changing for many stroke patients. Therapeutic hypothermia, the process of cooling the body or brain to preserve organ integrity, is one of the most potent neuroprotectants in both clinical and preclinical contexts. The rapid intervention has been linked to more favorable clinical results. This study focuses on the pathogenesis of stroke, as well as its recent advancements, future prospects, and potential therapeutic targets in stroke therapy.
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Affiliation(s)
- Priya Bindal
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Affiliated to I.K Gujral Punjab Technical University, Jalandhar, Punjab, India
| | - Vishal Kumar
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Affiliated to I.K Gujral Punjab Technical University, Jalandhar, Punjab, India
| | - Lakshay Kapil
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Affiliated to I.K Gujral Punjab Technical University, Jalandhar, Punjab, India
| | - Charan Singh
- Department of Pharmaceutical Sciences, HNB Garhwal University (A Central University), Chauras Campus, Distt. Tehri Garhwal, Uttarakhand, 246174, India
| | - Arti Singh
- Department of Pharmacology, ISF College of Pharmacy, Moga 142001, Affiliated to I.K Gujral Punjab Technical University, Jalandhar, Punjab, India.
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5
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Zhu A, Rajendram P, Tseng E, Coutts SB, Yu AYX. Alteplase or tenecteplase for thrombolysis in ischemic stroke: An illustrated review. Res Pract Thromb Haemost 2022; 6:e12795. [PMID: 36186106 PMCID: PMC9487449 DOI: 10.1002/rth2.12795] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/21/2022] [Accepted: 07/22/2022] [Indexed: 11/09/2022] Open
Abstract
Intravenous thrombolysis is a standard of care treatment for patients with acute ischemic stroke. Tissue plasminogen activator (tPA) has been the main thrombolytic agent used since the publication of the seminal National Institutes of Neurological Disorders and Stroke trial in 1995. There is now mounting evidence to support the routine use of Tenecteplase (TNK) to treat acute ischemic stroke. TNK is a genetically modified tPA with higher fibrin specificity, longer half-life, and reduced systemic coagulopathy. In this illustrated review, we compare the indications, doses, mechanisms of action, efficacy and safety of TNK and tPA. We provide an overview of published clinical trials studying TNK in acute ischemic stroke, including dose-escalation studies and head-to-head comparisons with tPA. Finally, we summarize current acute stroke guideline recommendations and suggest treatment algorithms to manage the two main complications of intravenous thrombolysis: symptomatic intracerebral hemorrhage and angioedema.
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Affiliation(s)
- Annie Zhu
- Department of Medicine (Neurology)University of Toronto, Sunnybrook Health Sciences CentreTorontoOntarioCanada
| | - Phavalan Rajendram
- Department of Medicine (Neurology)University of Toronto, Sunnybrook Health Sciences CentreTorontoOntarioCanada
| | - Eric Tseng
- Department of Medicine (Hematology)University of Toronto, Unity Health TorontoTorontoOntarioCanada
| | - Shelagh B. Coutts
- Department of Clinical Neurosciences, Radiology and Community Health SciencesHotchkiss Brain Institute, Cumming School of Medicine, University of CalgaryCalgaryAlbertaCanada
| | - Amy Y. X. Yu
- Department of Medicine (Neurology)University of Toronto, Sunnybrook Health Sciences CentreTorontoOntarioCanada
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6
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Barzkar N, Jahromi ST, Vianello F. Marine Microbial Fibrinolytic Enzymes: An Overview of Source, Production, Biochemical Properties and Thrombolytic Activity. Mar Drugs 2022; 20:46. [PMID: 35049901 PMCID: PMC8779250 DOI: 10.3390/md20010046] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/28/2021] [Accepted: 12/31/2021] [Indexed: 02/01/2023] Open
Abstract
Cardiovascular diseases (CVDs) have emerged as a major threat to global health resulting in a decrease in life expectancy with respect to humans. Thrombosis is one of the foremost causes of CVDs, and it is characterized by the unwanted formation of fibrin clots. Recently, microbial fibrinolytic enzymes due to their specific features have gained much more attention than conventional thrombolytic agents for the treatment of thrombosis. Marine microorganisms including bacteria and microalgae have the significant ability to produce fibrinolytic enzymes with improved pharmacological properties and lesser side effects and, hence, are considered as prospective candidates for large scale production of these enzymes. There are no studies that have evaluated the fibrinolytic potential of marine fungal-derived enzymes. The current review presents an outline regarding isolation sources, production, features, and thrombolytic potential of fibrinolytic biocatalysts from marine microorganisms identified so far.
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Affiliation(s)
- Noora Barzkar
- Department of Marine Biology, Faculty of Marine Science and Technology, University of Hormozgan, Bandar Abbas 74576, Iran
| | - Saeid Tamadoni Jahromi
- Persian Gulf and Oman Sea Ecology Research Center, Iranian Fisheries Sciences Research Institute, Agricultural Research Education and Extension Organization (AREEO), Bandar Abbas 93165, Iran
| | - Fabio Vianello
- Department of Comparative Biomedicine and Food Science, University of Padova, Viale dell’Università 16, 35020 Legnaro, Italy;
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7
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Hendley SA, Dimov A, Bhargava A, Snoddy E, Mansour D, Afifi RO, Wool GD, Zha Y, Sammet S, Lu ZF, Ahmed O, Paul JD, Bader KB. Assessment of histological characteristics, imaging markers, and rt-PA susceptibility of ex vivo venous thrombi. Sci Rep 2021; 11:22805. [PMID: 34815441 PMCID: PMC8610976 DOI: 10.1038/s41598-021-02030-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 11/08/2021] [Indexed: 12/27/2022] Open
Abstract
Venous thromboembolism is a significant source of morbidity and mortality worldwide. Catheter-directed thrombolytics is the primary treatment used to relieve critical obstructions, though its efficacy varies based on the thrombus composition. Non-responsive portions of the specimen often remain in situ, which prohibits mechanistic investigation of lytic resistance or the development of diagnostic indicators for treatment outcomes. In this study, thrombus samples extracted from venous thromboembolism patients were analyzed ex vivo to determine their histological properties, susceptibility to lytic therapy, and imaging characteristics. A wide range of thrombus morphologies were observed, with a dependence on age and etymology of the specimen. Fibrinolytic inhibitors including PAI-1, alpha 2-antiplasmin, and TAFI were present in samples, which may contribute to the response venous thrombi to catheter-directed thrombolytics. Finally, a weak but significant correlation was observed between the response of the sample to lytic drug and its magnetic microstructure assessed with a quantitative MRI sequence. These findings highlight the myriad of changes in venous thrombi that may promote lytic resistance, and imaging metrics that correlate with treatment outcomes.
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Affiliation(s)
- Samuel A Hendley
- Committee on Medical Physics, University of Chicago, Chicago, IL, 60637, USA
| | - Alexey Dimov
- Department of Radiology, Weill Cornell Medicine, New York, NY, 10021, USA
| | - Aarushi Bhargava
- Department of Radiology, University of Chicago, Chicago, IL, 60637, USA
| | - Erin Snoddy
- Department of Radiology, University of Chicago, Chicago, IL, 60637, USA
| | - Daniel Mansour
- Department of Radiology, University of Chicago, Chicago, IL, 60637, USA
| | - Rana O Afifi
- Department of Cardiothoracic and Vascular Surgery, University of Texas at Houston, Houston, TX, 77030, USA
| | - Geoffrey D Wool
- Department of Pathology, University of Chicago, Chicago, IL, 60637, USA
| | - Yuanyuan Zha
- The Human Immunological Monitoring Facility, University of Chicago, Chicago, IL, 60637, USA
| | - Steffen Sammet
- Committee on Medical Physics, University of Chicago, Chicago, IL, 60637, USA
- Department of Radiology, University of Chicago, Chicago, IL, 60637, USA
| | - Zheng Feng Lu
- Committee on Medical Physics, University of Chicago, Chicago, IL, 60637, USA
- Department of Radiology, University of Chicago, Chicago, IL, 60637, USA
| | - Osman Ahmed
- Department of Radiology, University of Chicago, Chicago, IL, 60637, USA
| | - Jonathan D Paul
- Department of Medicine, University of Chicago, Chicago, IL, 60637, USA
| | - Kenneth B Bader
- Committee on Medical Physics, University of Chicago, Chicago, IL, 60637, USA.
- Department of Radiology, University of Chicago, Chicago, IL, 60637, USA.
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Wiśniewski A. Safety and efficacy of intravenous thrombolytic treatment in wake-up stroke: Experiences from a single center. Brain Behav 2021; 11:e02152. [PMID: 33939326 PMCID: PMC8213934 DOI: 10.1002/brb3.2152] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 04/01/2021] [Accepted: 04/01/2021] [Indexed: 01/01/2023] Open
Abstract
OBJECTIVES Wake-up stroke is an important clinical problem that may account for a quarter of all ischemic strokes. This study aimed to establish the safety and efficacy of intravenous thrombolytic treatment of wake-up strokes by comparing it to the standard thrombolysis treatment in strokes with clear onsets and wake-up strokes that did not receive reperfusion therapy. METHODS This retrospective study enrolled 95 patients with ischemic strokes who underwent thrombolytic treatment with alteplase, including nine patients with wake-up strokes. The safety profile (mortality and intracranial bleeding) and efficacy (clinical and functional outcomes on admission, discharge, and 90 days after stroke onset) were evaluated. RESULTS When assessed using the modified Rankin scale (mRs), the patients with wake-up strokes had significantly more favorable functional outcomes on discharge when compared to those who received standard thrombolysis (p = .0289). No significant differences were noted when the favorable outcome rate (mRs score = 0-2) at three months post-thrombolysis (Odds ratio [OR] = 2.07; 95% confidence interval [CI] = 0.41-10.6; p = .3807) and safety outcomes (death during hospitalization: OR = 0.49; 95% CI = 0.03-9.11; p = .6295 and intracranial bleeding 24 hr after treatment: OR = 0.43; 95% CI = 0.02-7.58; p = .5707) were compared between the two groups. The Cochran-Mantel-Haenchel shift analysis showed a significantly more favorable distribution of the mRs scores at three months after the stroke onset in the patients with wake-up strokes who were treated with alteplase compared to those who did not receive thrombolysis (OR = 1.42; 95% CI = 1.01-1.82; p = .0426). CONCLUSIONS Our study demonstrated that in patients who awaken with stroke symptoms, intravenous thrombolytic treatment is a safe procedure that may lead to favorable outcomes. Further studies should be performed to increase the size of the group of patients with wake-up strokes who can be treated with reperfusion therapy.
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Affiliation(s)
- Adam Wiśniewski
- Department of NeurologyFaculty of MedicineCollegium Medium in Bydgoszcz, Nicolaus Copernicus University in ToruńBydgoszczPoland
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9
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Abstract
Wake-up stroke (WUS) or ischemic stroke occurring during sleep accounts for 14%-29.6% of all ischemic strokes. Management of WUS is complicated by its narrow therapeutic time window and attributable risk factors, which can affect the safety and efficacy of administering intravenous (IV) tissue plasminogen activator (t-PA). This manuscript will review risk factors of WUS, with a focus on obstructive sleep apnea, potential mechanisms of WUS, and evaluate studies assessing safety and efficacy of IV t-PA treatment in WUS patients guided by neuroimaging to estimate time of symptom onset. The authors used PubMed (1966 to March 2018) to search for the term "Wake-Up Stroke" cross-referenced with "pathophysiology," ''pathogenesis," "pathology," "magnetic resonance imaging," "obstructive sleep apnea," or "treatment." English language Papers were reviewed. Also reviewed were pertinent papers from the reference list of the above-matched manuscripts. Studies that focused only on acute Strokes with known-onset of symptoms were not reviewed. Literature showed several potential risk factors associated with increased risk of WUS. Although the onset of WUS is unknown, a few studies investigated the potential benefit of magnetic resonance imaging (MRI) in estimating the age of onset which encouraged conducting clinical trials assessing the efficacy of MRI-guided thrombolytic therapy in WUS.
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Abstract
ST-segment elevation myocardial infarction (STEMI) is the most acute manifestation of coronary artery disease and is associated with great morbidity and mortality. A complete thrombotic occlusion developing from an atherosclerotic plaque in an epicardial coronary vessel is the cause of STEMI in the majority of cases. Early diagnosis and immediate reperfusion are the most effective ways to limit myocardial ischaemia and infarct size and thereby reduce the risk of post-STEMI complications and heart failure. Primary percutaneous coronary intervention (PCI) has become the preferred reperfusion strategy in patients with STEMI; if PCI cannot be performed within 120 minutes of STEMI diagnosis, fibrinolysis therapy should be administered to dissolve the occluding thrombus. The initiation of networks to provide around-the-clock cardiac catheterization availability and the generation of standard operating procedures within hospital systems have helped to reduce the time to reperfusion therapy. Together with new advances in antithrombotic therapy and preventive measures, these developments have resulted in a decrease in mortality from STEMI. However, a substantial amount of patients still experience recurrent cardiovascular events after STEMI. New insights have been gained regarding the pathophysiology of STEMI and feed into the development of new treatment strategies.
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11
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Identification of a new serine protease from polychaeta, Marphysa sanguinea, for its thrombolytic and anticoagulant activity. KOREAN J CHEM ENG 2017. [DOI: 10.1007/s11814-016-0331-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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12
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Abstract
Given that alteplase has been the only approved thrombolytic agent for acute ischemic stroke for almost two decades, there has been intense interest in more potent and safer agents over the last few years. Tenecteplase is a bioengineered mutation of alteplase with advantageous pharmacodynamics and pharmacokinetics. The superiority of tenecteplase over alteplase has been proven by in vitro and animal studies, and it was approved for use in myocardial infarction more than a decade ago. In patients with acute ischemic stroke, tenecteplase has shown promise in randomized phase II trials and the drug is currently being tested in four phase III clinical trials that will start delivering definite results in the near future: NOR-TEST (NCT01949948), TASTE (ACTRN12613000243718), TEMPO-2 (NCT02398656), and TALISMAN (NCT02180204).
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13
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Ahmed F, Rahman MS. Preliminary assessment of free radical scavenging, thrombolytic and membrane stabilizing capabilities of organic fractions of Callistemon citrinus (Curtis.) skeels leaves. BMC COMPLEMENTARY AND ALTERNATIVE MEDICINE 2016; 16:247. [PMID: 27460997 PMCID: PMC4962397 DOI: 10.1186/s12906-016-1239-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Accepted: 07/23/2016] [Indexed: 01/31/2023]
Abstract
Background Callistemon citrinus (Curtis.) (Family- Myrtaceae) is a popular evergreen shrub in Bangladesh. In the present study, the leaves of this plant have been assessed comprehensively for free radical scavenging, thrombolytic and membrane stabilizing activities. Methods The leaves were collected, powdered and extracted with methanol. The extract was then concentrated and successively fractionated into petroleum ether, carbon tetrachloride, chloroform and aqueous soluble fractions. The extractives were investigated for free radical scavenging, thrombolytic and membrane stabilizing activities. Results In case of 1,1 diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide radical scavenging assays, the crude methanol extract of the leaves showed the highest free radical scavenging activity among the tested materials including standard ascorbic acid (p = 0.0000). Besides, this extract was also found significantly rich (p = 0.0000) in phenolics and flavonoids compared to other organic fractions. In thrombolytic study, the petroleum ether fraction exhibited significantly stronger thrombolysis (p = 0.024) than other leaf extractives but was weaker than the standard streptokinase. In membrane stabilizing assay, the activity of chloroform fraction was similar to that of standard acetylsalicylic acid (p = 1.000) in hypotonic solution induced hemolysis. However, membrane stabilization activity of this chloroform fraction was found significantly stronger than that of the standard (p = 0.0000) in heat induced hemolysis. Conclusion This study has revealed the medicinal capabilities of different organic fractions of C. citrinus displaying free radical scavenging, thrombolysis and membrane stabilizing antiinflammatory potentials. Further bioactivity guided isolation is required to obtain pharmacologically secondary metabolites.
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14
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Kumar A, Pulicherla KK, Sambasiva Rao KRS. Development and validation of an indirect competitive ELISA for quantification of recombinant staphylokinase in rabbit plasma: Application to pharmacokinetic study. J Immunoassay Immunochem 2015; 37:228-42. [PMID: 26674740 DOI: 10.1080/15321819.2015.1126600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The relatively short circulatory half-life (2-3 min) of staphylokinase is a major drawback in the development of SAK- (staphylokinase) based thrombolytic drug. A rapid and sensitive method, based on indirect competitive ELISA, was developed and validated for quantitative determination of SAK in rabbit plasma. The dynamic range of the assay varied between 0.41 ± 0.16 μg/L and 9.03 ± 0.38 μg/L (R(2) = 0.98) for SAK in rabbit plasma. There were no dilution linearity issues apparent with this assay. The precision (% CV) ranged from 4.6-9.7% for the intraassay and from 17.1-19.3% for interassay. This validated method was successfully employed for evaluation of various pharmacokinetic parameters of SAK in rabbit.
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Affiliation(s)
- Anmol Kumar
- a Centre for Cellular & Molecular Biology , Hyderabad , India.,b Department of Biotechnology , Acharya Nagarjuna University , Guntur , India
| | - K K Pulicherla
- c Centre for Bioseparation Technology , VIT University , Vellore , India
| | - K R S Sambasiva Rao
- b Department of Biotechnology , Acharya Nagarjuna University , Guntur , India
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Kumar A, Pulicherla KK, Mayuren C, Kotra S, Rao KRS. Evaluation of a multifunctional staphylokinase variant with thrombin inhibition and antiplatelet aggregation activities produced from salt-inducible E. coli GJ1158. Can J Physiol Pharmacol 2013; 91:839-47. [PMID: 24144055 DOI: 10.1139/cjpp-2012-0467] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Reocclusion is one of the major root causes for secondary complications that arise during thrombolytic therapy. A multifunctional staphylokinase variant SRH (staphylokinase (SAK) linked with tripeptide RGD and didecapeptide Hirulog) with antiplatelet and antithrombin activities in addition to clot specific thrombolytic function, was developed to address the reocclusion problem. We preferred to use Escherichia coli GJ1158 as the host in this study for economic production of SRH by osmotic (0.3 mol/L sodium chloride) induction, to overcome the problems associated with the yeast expression system. The therapeutic potential of SRH was evaluated in the murine model of vascular thrombosis. The SAK protein (1 mg/kg body mass) and SRH protein (1 mg/kg and 2 mg/kg) were administered intravenously to the different treatment groups. The results have shown a dose-dependent antithrombotic effect in carrageenan-induced mouse tail thrombosis. The thrombin time, activated partial thromboplastin time, and prothrombin time were significantly prolonged (p < 0.05) in the SRH-infused groups. Moreover, SRH inhibited platelet aggregation in a dose-dependent manner (p < 0.05), while the bleeding time was significantly (p < 0.05) prolonged. All of these results inferred that the osmotically produced multifunctional fusion protein SRH (SAK-RGD-Hirulog) is a promising thrombolytic agent, and one which sustained its multifunctionality in the animal models.
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Affiliation(s)
- Anmol Kumar
- a Department of Biotechnology, Acharya Nagarjuna University, Nagarjuna Nagar, Guntur 522510, India
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Tumlin J, Goldman J, Spiegel DM, Roer D, Ntoso KA, Blaney M, Jacobs J, Gillespie BS, Begelman SM. A phase III, randomized, double-blind, placebo-controlled study of tenecteplase for improvement of hemodialysis catheter function: TROPICS 3. Clin J Am Soc Nephrol 2010; 5:631-6. [PMID: 20133491 DOI: 10.2215/cjn.06520909] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND AND OBJECTIVES Despite widespread use of tunneled hemodialysis (HD) catheters, their utility is limited by the development of thrombotic complications. To address this problem, this study investigated whether the thrombolytic agent tenecteplase can restore blood flow rates (BFRs) in dysfunctional HD catheters. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS In this randomized, double-blind study, patients with dysfunctional tunneled HD catheters, defined as a BFR <300 ml/min at -250 mmHg pressure in the arterial line, received 1-hour intracatheter dwell with tenecteplase (2 mg) or placebo. The primary endpoint was the percentage of patients with BFR > or =300 ml/min and an increase of > or =25 ml/min above baseline 30 minutes before and at the end of HD. Safety endpoints included the incidence of hemorrhagic, thrombotic, and infectious complications. RESULTS Eligible patients (n = 149) were treated with tenecteplase (n = 74) or placebo (n = 75). Mean baseline BFR was similar for the tenecteplase and placebo groups at 151 and 137 ml/min, respectively. After a 1-hour dwell, 22% of patients in the tenecteplase group had functional catheters compared with 5% among placebo controls (P = 0.004). At the end of dialysis, mean change in BFR was 47 ml/min in the tenecteplase group versus 12 ml/min in the placebo group (P = 0.008). Four catheter-related bloodstream infections (one tenecteplase, three placebo) and one thrombosis (tenecteplase) were observed. There were no reports of intracranial hemorrhage, major bleeding, embolic events, or catheter-related complications. CONCLUSIONS Tenecteplase improved HD catheter function and had a favorable safety profile compared with placebo.
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Affiliation(s)
- James Tumlin
- Department of Internal Medicine, Division of Nephrology, University of Tennessee College of Medicine in Chattanooga, Director, Southeast Renal Research Institute, 2300 East Third Street, Suite 100, Chattanooga, TN 37404, USA.
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Melandri G, Vagnarelli F, Calabrese D, Semprini F, Nanni S, Branzi A. Review of tenecteplase (TNKase) in the treatment of acute myocardial infarction. Vasc Health Risk Manag 2009; 5:249-56. [PMID: 19436656 PMCID: PMC2672445 DOI: 10.2147/vhrm.s3848] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
TNKase is a genetically engineered variant of the alteplase molecule. Three different mutations result in an increase of the plasma half-life, of the resistance to plasminogen-activator inhibitor 1 and of the thrombolytic potency against platelet-rich thrombi. Among available agents in clinical practice, TNKase is the most fibrin-specific molecule and can be delivered as a single bolus intravenous injection. Several large-scale clinical trials have enrolled more than 27,000 patients with acute myocardial infarction, making the use of this drug truly evidence-based. TNKase is equivalent to front-loaded alteplase in terms of mortality and is the only bolus thrombolytic drug for which this equivalence has been formally demonstrated. TNKase appears more potent than alteplase when symptoms duration lasts more than 4 hours. Also, TNKase significantly reduces the rate of major bleeds and the need for blood transfusions. The efficacy of TNKase may be further improved by enoxaparin substitution for unfractionated heparin, provided that enoxaparin dose adjustment is made for patients more than 75 years old. Hitherto, the small available randomized studies and international clinical registries suggest that pre-hospital TNKase is as effective as primary angioplasty, thus laying the foundations for a new fibrinolytic, TNKase-based strategy as the backbone of reperfusion in acute myocardial infarction.
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Apte-Deshpnade A, Mandal G, Soorapaneni S, Prasad B, Kumar J, Padmanabhan S. High-level expression of non-glycosylated and active staphylokinase from Pichia pastoris. Biotechnol Lett 2009; 31:811-7. [PMID: 19214390 DOI: 10.1007/s10529-009-9938-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2008] [Revised: 01/19/2009] [Accepted: 01/23/2009] [Indexed: 11/25/2022]
Abstract
Staphylokinase (SAK) is a promising thrombolytic agent for treating blood-clotting disorders. Recombinant SAK (rSAK) was produced after integration of the gene into Pichia pastoris genome. The recombinant Pichia carrying multiple insertions of the SAK gene yielded high-level (approximately 1 g/l) of extracellular glycosylated rSAK (approximately 18 kDa) with negligible plasminogen activation activity. Addition of tunicamycin during the induction phase resulted in expression of non-glycosylated and highly active rSAK (approximately 15 kDa) from the same clone. Two simple steps of ion-exchange chromatography produced an homogenous rSAK of >95% purity which suitable for future structural and functional studies.
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Affiliation(s)
- Anjali Apte-Deshpnade
- Biotechnology R & D, Lupin Limited, 46A/47A, Nande Village, Mulshi Taluka, Pune 411042, India
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Hilleman DE, Tsikouris JP, Seals AA, Marmur JD. Fibrinolytic Agents for the Management of ST-Segment Elevation Myocardial Infarction. Pharmacotherapy 2007; 27:1558-70. [DOI: 10.1592/phco.27.11.1558] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Shi B, Yu A, Liu Y, Li J, Jin J, Dong C, Wu C. Locally activity-released bifunctional fusion protein enhances antithrombosis and alleviates bleeding risk. J Thromb Thrombolysis 2007; 24:283-92. [PMID: 17487572 DOI: 10.1007/s11239-007-0036-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Accepted: 04/09/2007] [Indexed: 11/29/2022]
Abstract
Despite the fact that lytic therapy of thromboembolic disorder has been achieved, reocclusion of the damaged vessels and bleeding complication frequently reduce the therapeutic effect. In order to prevent the vessel reocclusion and enhance the therapeutic effect, combining the anticoagulant with the thrombolytic was assumed. Herein, we propose that restraining but locally releasing anticoagulant activity in the vicinity of thrombus is a way to alleviate the bleeding risk. A bifunctional fusion protein, termed as SFH (Staphylokinase (SAK) linked by FXa recognition peptide at N-terminus of Hirudin (HV)), was designed. SFH retained thrombolytic activity but no anticoagulant activity in thrombus-free blood due to the extension of the N-terminus of HV. However, it could locally liberate intact HV and exhibit anticoagulant activity when FXa or fresh thrombus was present. At equimolar dose, both improved antithrombotic and thrombolytic effects of SFH were observed in kappa-carrageenin inducing mouse-tail thrombosis model and rat inferior vena cava thrombosis model, respectively. Moreover, we observed significantly lower bleeding risk in mice and rats treated with SFH than with the mixture of SAK and HV with monitoring TT (P < 0.01), aPTT (P < 0.05) and PT (P < 0.05), and bleeding time (P < 0.05). In conclusion, SFH is a promising bifunctional therapeutic candidate with lower bleeding risk.
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Affiliation(s)
- Bingxing Shi
- Key Lab of Experimental Hematology, Beijing Institute of Radiation Medicine, 27 Taiping Road, Beijing, 100850, PR China.
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21
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Imaging and Intervention in Acute Non-traumatic Arterial Condition. Emerg Radiol 2007. [DOI: 10.1007/978-3-540-68908-9_27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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Dager WE, Sanoski CA, Wiggins BS, Tisdale JE. Pharmacotherapy considerations in advanced cardiac life support. Pharmacotherapy 2007; 26:1703-29. [PMID: 17125434 DOI: 10.1592/phco.26.12.1703] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Cardiac arrest and sudden cardiac death remain major causes of mortality. Early intervention has been facilitated by emergency medical response systems and the development of training programs in basic life support and advanced cardiac life support (ACLS). Despite the implementation of these programs, the likelihood of a meaningful outcome in many life-threatening situations remains poor. Pharmacotherapy plays a role in the management of patients with cardiac arrest, with new guidelines for ACLS available in 2005 providing recommendations for the role of specific drug therapies. Epinephrine continues as a recommended means to facilitate defibrillation in patients with pulseless ventricular tachycardia or ventricular fibrillation; vasopressin is an alternative. Amiodarone is the primary antiarrhythmic drug that has been shown to be effective for facilitation of defibrillation in patients with pulseless ventricular tachycardia or fibrillation and is also used for the management of atrial fibrillation and hemodynamically stable ventricular tachycardia. Epinephrine and atropine are the primary agents used for the management of asystole and pulseless electrical activity. Treatment of electrolyte abnormalities, severe hypotension, pulmonary embolism, acute ischemic stroke, and toxicologic emergencies are important components of ACLS management. Selection of the appropriate drug, dose, and timing and route of administration are among the many challenges faced in this setting. Pharmacists who are properly educated and trained regarding the use of pharmacotherapy for patients requiring ACLS can help maximize the likelihood of positive patient outcomes.
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Affiliation(s)
- William E Dager
- University of California-Davis Medical Center, and the School of Medicine, University of California-Davis, Sacramento, California 95817-2201, USA.
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Erstad BL. Dosing of medications in morbidly obese patients in the intensive care unit setting. Intensive Care Med 2004; 30:18-32. [PMID: 14625670 DOI: 10.1007/s00134-003-2059-6] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/02/2003] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To derive recommendations for the dosing of commonly used medications in the morbidly obese patient in the ICU. DATA SOURCES Articles were obtained through computerized searches involving MEDLINE. The bibliographies of retrieved publications and textbooks were reviewed for additional references. STUDY SELECTION All studies involving the pharmacokinetics or pharmacodynamics of medications in obese subjects or patients. DATA EXTRACTION The emphasis was on studies involving morbidly obese patients but, in the absence of such data, investigations involving lesser forms of obesity were extracted. DATA SYNTHESIS There is a paucity of data upon which to make recommendations for dosing commonly used medications in the morbidly obese patient in the ICU, although recommendations were provided based on the available information. CONCLUSIONS There is clearly a need for more investigations involving dosing regimens of medications in the morbidly obese population. Until such studies are available, the clinician must try to derive the best dosing regimens for medications based on the limited pharmacokinetic data available for some agents and clinical judgement.
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Affiliation(s)
- Brian L Erstad
- Department of Pharmacy Practice and Science, College of Pharmacy, Tucson, Arizona 85721-0207, USA.
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Erstad BL. Dosing of medications in morbidly obese patients in the intensive care unit setting. Intensive Care Med 2003; 73:685-90. [PMID: 14625670 DOI: 10.1111/j.1365-2125.2011.04159.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
OBJECTIVE To derive recommendations for the dosing of commonly used medications in the morbidly obese patient in the ICU. DATA SOURCES Articles were obtained through computerized searches involving MEDLINE. The bibliographies of retrieved publications and textbooks were reviewed for additional references. STUDY SELECTION All studies involving the pharmacokinetics or pharmacodynamics of medications in obese subjects or patients. DATA EXTRACTION The emphasis was on studies involving morbidly obese patients but, in the absence of such data, investigations involving lesser forms of obesity were extracted. DATA SYNTHESIS There is a paucity of data upon which to make recommendations for dosing commonly used medications in the morbidly obese patient in the ICU, although recommendations were provided based on the available information. CONCLUSIONS There is clearly a need for more investigations involving dosing regimens of medications in the morbidly obese population. Until such studies are available, the clinician must try to derive the best dosing regimens for medications based on the limited pharmacokinetic data available for some agents and clinical judgement.
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Affiliation(s)
- Brian L Erstad
- Department of Pharmacy Practice and Science, College of Pharmacy, Tucson, Arizona 85721-0207, USA.
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Wu SC, Castellino FJ, Wong SL. A fast-acting, modular-structured staphylokinase fusion with Kringle-1 from human plasminogen as the fibrin-targeting domain offers improved clot lysis efficacy. J Biol Chem 2003; 278:18199-206. [PMID: 12646571 DOI: 10.1074/jbc.m210919200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To develop a fast-acting clot dissolving agent, a clot-targeting domain derived from the Kringle-1 domain in human plasminogen was fused to the C-terminal end of staphylokinase with a linker sequence in between. Production of this fusion protein in Bacillus subtilis and Pichia pastoris was examined. The Kringle domain in the fusion protein produced from B. subtilis was improperly folded because of its complicated disulfide-bond profile, whereas the staphylokinase domain produced from P. pastoris was only partially active because of an N-linked glycosylation. A change of the glycosylation residue, Thr-30, to alanine resulted in a non-glycosylated biologically active fusion. The resulting mutein, designated SAKM3-L-K1, was overproduced in P. pastoris. Each domain in SAKM3-L-K1 was functional, and this fusion showed fibrin binding ability by binding directly to plasmin-digested clots. In vitro fibrin clot lysis in a static environment and plasma clot lysis in a flow-cell system demonstrated that the engineered fusion outperformed the non-fused staphylokinase. The time required for 50% clot lysis was reduced by 20 to 500% under different conditions. Faster clot lysis can potentially reduce the degree of damage to occluded heart tissues.
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Affiliation(s)
- Sau-Ching Wu
- Division of Molecular, Cellular, and Microbial Biology, Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada
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