The time to initiate intravenous thrombolysis for acute ischemic stroke is generally limited to within 4.5 hours after the onset of symptoms. Some trials have suggested that the treatment window may ...be extended in patients who are shown to have ischemic but not yet infarcted brain tissue on imaging.
We conducted a multicenter, randomized, placebo-controlled trial involving patients with ischemic stroke who had hypoperfused but salvageable regions of brain detected on automated perfusion imaging. The patients were randomly assigned to receive intravenous alteplase or placebo between 4.5 and 9.0 hours after the onset of stroke or on awakening with stroke (if within 9 hours from the midpoint of sleep). The primary outcome was a score of 0 or 1 on the modified Rankin scale, on which scores range from 0 (no symptoms) to 6 (death), at 90 days. The risk ratio for the primary outcome was adjusted for age and clinical severity at baseline.
After 225 of the planned 310 patients had been enrolled, the trial was terminated because of a loss of equipoise after the publication of positive results from a previous trial. A total of 113 patients were randomly assigned to the alteplase group and 112 to the placebo group. The primary outcome occurred in 40 patients (35.4%) in the alteplase group and in 33 patients (29.5%) in the placebo group (adjusted risk ratio, 1.44; 95% confidence interval CI, 1.01 to 2.06; P = 0.04). Symptomatic intracerebral hemorrhage occurred in 7 patients (6.2%) in the alteplase group and in 1 patient (0.9%) in the placebo group (adjusted risk ratio, 7.22; 95% CI, 0.97 to 53.5; P = 0.05). A secondary ordinal analysis of the distribution of scores on the modified Rankin scale did not show a significant between-group difference in functional improvement at 90 days.
Among the patients in this trial who had ischemic stroke and salvageable brain tissue, the use of alteplase between 4.5 and 9.0 hours after stroke onset or at the time the patient awoke with stroke symptoms resulted in a higher percentage of patients with no or minor neurologic deficits than the use of placebo. There were more cases of symptomatic cerebral hemorrhage in the alteplase group than in the placebo group. (Funded by the Australian National Health and Medical Research Council and others; EXTEND ClinicalTrials.gov numbers, NCT00887328 and NCT01580839.).
In the management of acute ischemic stroke, guideline adherence is often suboptimal, particularly for intravenous thrombolysis or anticoagulation for atrial fibrillation. We sought to improve stroke ...care quality via a collaborative model, the Breakthrough Series (BTS)-Stroke activity, in a nationwide, multi-center activity in Taiwan. A BTS Collaborative, a short-term learning system for a large number of multidisciplinary teams from hospitals, was applied to enhance acute ischemic stroke care quality. Twenty-four hospitals participated in and submitted data for this stroke quality improvement campaign in 2010-2011. Totally, 14 stroke quality measures, adopted from the Get With The Guideline (GWTG)-Stroke program, were used to evaluate the performance and outcome of the ischemic stroke patients. Data for a one-year period from 24 hospitals with 13,181 acute ischemic stroke patients were analyzed. In 14 hospitals, most stroke quality measures improved significantly during the BTS-activity compared with a pre-BTS-Stroke activity period (2006-08). The rate of intravenous thrombolysis increased from 1.2% to 4.6%, door-to-needle time ≤60 minutes improved from 7.1% to 50.8%, symptomatic hemorrhage after intravenous thrombolysis decreased from 11.0% to 5.6%, and anticoagulation therapy for atrial fibrillation increased from 32.1% to 64.1%. The yearly composite measures of five stroke quality measures revealed significant improvements from 2006 to 2011 (75% to 86.3%, p<0.001). The quarterly composite measures also improved significantly during the BTS-Stroke activity. In conclusion, a BTS collaborative model is associated with improved guideline adherence for patients with acute ischemic stroke. GWTG-Stroke recommendations can be successfully applied in countries besides the United States.
Chemerin, a novel adipokine, plays a role in the inflammation status of vascular endothelial cells. Hypoxia causes endothelial-cell proliferation, migration, and angiogenesis. This study was aimed at ...evaluating the protein and mRNA expression of chemerin after exposure of human coronary artery endothelial cells (HCAECs) to hypoxia.
Cultured HCAECs underwent hypoxia for different time points. Chemerin protein levels increased after 4 h of hypoxia at 2.5% O2, with a peak of expression of tumor necrosis factor-alpha (TNF-alpha) at 1 h. Both hypoxia and exogenously added TNF-alpha during normoxia stimulated chemerin expression, whereas an ERK inhibitor (PD98059), ERK small interfering RNA (siRNA), or an anti-TNF-alpha antibody attenuated the chemerin upregulation induced by hypoxia. A gel shift assay indicated that hypoxia induced an increase in DNA-protein binding between the chemerin promoter and transcription factor SP1. A luciferase assay confirmed an increase in transcriptional activity of SP1 on the chemerin promoter during hypoxia. Hypoxia significantly increased the tube formation and migration of HCAECs, whereas PD98059, the anti-TNF-alpha antibody, and chemerin siRNA each attenuated these effects.
Hypoxia activates chemerin expression in cultured HCAECs. Hypoxia-induced chemerin expression is mediated by TNF-alpha and at least in part by the ERK pathway. Chemerin increases early processes of angiogenesis by HCAECs after hypoxic treatment.
The aim of this study was to investigate the effect of dietary supplementation of nanosize zinc on zinc digestibility, growth performances, immune response and serum parameters of weanling piglets. ...Ninety‐six LYD weanling piglets were assigned to control, zinc oxide (ZnO), organic‐Zn (Zn‐methionine) and nanosize ZnO (nano‐Zn) groups with four replicates. The zinc was at the 120 mg/kg level in the treatment group's diet, while the control group's was 80 mg/kg Zn. The experiment results indicated that the nano‐Zn and organic‐Zn groups had significantly higher Zn digestibility compared to the ZnO and control groups. For the immune response traits, the IgG level and goat red blood cells (GRBC) antibody titer were nano‐Zn and organic‐Zn>ZnO>control; in the phytohemagglutinin (PHA) challenge test result, nano‐Zn>organic‐Zn>ZnO>control; in regard to the γ‐globulin level, nano‐Zn and organic‐Zn>ZnO and control, with significant difference between groups. In the serum parameters aspect, serum Zn concentration in nano‐Zn and organic‐Zn groups were higher than in the ZnO and control groups, serum growth hormone concentration was increased in the nano‐Zn group than in the other groups. In conclusion, nanosize zinc oxide for dietary supplementation can increase zinc digestibility, serum growth hormone levels and carbonic anhydrase activity and enhance the immune response of weanling piglets.
MicroRNAs play an important role in cardiac remodeling. MicroRNA 499 (miR499) is highly enriched in cardiomyocytes and targets the gene for Calcineurin A (CnA), which is associated with mitochondrial ...fission and apoptosis. The mechanism regulating miR499 in stretched cardiomyocytes and in volume overloaded heart is unclear. We sought to investigate the mechanism regulating miR499 and CnA in stretched cardiomyocytes and in volume overload-induced heart failure.
Rat cardiomyocytes grown on a flexible membrane base were stretched via vacuum to 20% of maximum elongation at 60 cycles/min. An in vivo model of volume overload with aorta-caval shunt in adult rats was used to study miR499 expression. Mechanical stretch downregulated miR499 expression, and enhanced the expression of CnA protein and mRNA after 12 hours of stretch. Expression of CnA and calcineurin activity was suppressed with miR499 overexpression; whereas, expression of dephosphorylated dynamin-related protein 1 (Drp1) was suppressed with miR499 overexpression and CnA siRNA. Adding p53 siRNA reversed the downregulation of miR499 when stretched. A gel shift assay and promoter-activity assay demonstrated that stretch increased p53 DNA binding activity but decreased miR499 promoter activity. When the miR499 promoter p53-binding site was mutated, the inhibition of miR499 promoter activity with stretch was reversed. The in vivo aorta-caval shunt also showed downregulated myocardial miR499 and overexpression of miR499 suppressed CnA and cellular apoptosis.
The miR499-controlled apoptotic pathway involving CnA and Drp1 in stretched cardiomyocytes may be regulated by p53 through the transcriptional regulation of miR499.
Research on the cardiovascular toxicity of angiogenesis inhibitors among patients with cancer in Taiwan is lacking. This observational study explored the risk of major adverse cardiovascular events ...(MACEs) associated with angiogenesis inhibitors in Taiwan.
We conducted a nested case-control study using the TCR (Taiwan Cancer Registry) linked with the Taiwan National Insurance Claim Database. We matched every case with 4 controls using risk-set sampling by index date, age, sex, cancer type, and cancer diagnosis date. Conditional logistic regression was used to evaluate the risks of MACEs and different cardiovascular events using propensity score adjustment or matching. Sensitivity analyses were used to evaluate the risks matched by cancer stages or exposure within 1 year. Among a cohort of 284 292 after the exclusion of prevalent cases, the incidences of MACEs among the overall cohort and those exposed to angiogenesis inhibitors were 22.5 and 32.5 events per 1000 person-years, respectively. We matched 17 817 cases with 70 740 controls, with a mean age of 74.9 years, and 56.8% of patients were men. After propensity score adjustment, angiogenesis inhibitors were associated with increased risks of MACEs (odds ratio, 4.56; 95% CI, 1.78-11.59). Significantly increased risks were noted for heart failure hospitalization, myocardial infarction, cerebrovascular accident, and venous thromboembolism, but not for new-onset atrial fibrillation. Similar results were observed after matching by cancer stage or restriction of 1-year exposure.
Angiogenesis inhibitors were associated with increased risks of MACEs among patients with various malignancies in Taiwan but were not associated with new-onset atrial fibrillation.
Vincristine is a clinically used antimicrotubule drug for treating patients with lymphoma. Due to its property of increasing platelet counts, vincristine is also used to treat patients with immune ...thrombocytopenia. Moreover, antiplatelet agents were reported to be beneficial in thrombotic thrombocytopenic purpura (TTP). Therefore, we investigated the detailed mechanisms underlying the antiplatelet effect of vincristine. Our results revealed that vincristine inhibited platelet aggregation induced by collagen, but not by thrombin, arachidonic acid, and the thromboxane A2 analog U46619, suggesting that vincristine exerts higher inhibitory effects on collagen-mediated platelet aggregation. Vincristine also reduced collagen-mediated platelet granule release and calcium mobilization. In addition, vincristine inhibited glycoprotein VI (GPVI) signaling, including Syk, phospholipase Cγ2, protein kinase C, Akt, and mitogen-activated protein kinases. In addition, the in vitro PFA-100 assay revealed that vincristine did not prolong the closure time, and the in vivo study tail bleeding assay showed that vincristine did not prolong the tail bleeding time; both findings suggested that vincristine may not affect normal hemostasis. In conclusion, we demonstrated that vincristine exerts antiplatelet effects at least in part through the suppression of GPVI signaling. Moreover, this property of antiplatelet activity of vincristine may provide additional benefits in the treatment of TTP.
Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a rare disorder. However, the outcome is still variable with different serological and tumor associations, and the elements to good ...response with less relapse is yet to be elucidated.
We present a case and obtain a literature review of patients with PERM and make comparisons based on different serological groups. We also analyze patients with idiopathic PERM that had detailed medical records.
81 patients were collected and analyzed. The largest group were glycine receptor-antibody (GlyR-Ab)-positive (70%), and the seropositive-GlyR-Ab-negative group had better response to immunotherapy. Malignancy can occur up to 2 years from the presentation of PERM. Among the 18 cases with detailed records, the patients who had good outcome initiate immunotherapy within 2 months from presentation. 9 of the 12 patients who experienced no relapse had non-steroid immunotherapy. The maximal interval time of relapse was 24 months.
We recommend tumor surveillance up to 2 years in patients with PERM and early administration of immunotherapies and maintain with non-steroid immunotherapy with or without oral corticosteroid for a minimum of 2 years to reduce the risk of relapse in GlyR-Ab-positive patients.
•Antibodies other than glycine receptor had better response to immunotherapy but tends to have higher relapse.•Malignancy occurs up to 2 years from progressive encephalomyelitis with rigidity and myoclonus.•Recommend early immunotherapies and maintain 2 years in glycine receptor-positive patients.
•Using a nationwide prospective stroke registry to evaluate several machine learning approaches for prediction of stroke outcomes.•Over two hundred clinical variables are screened to identify ...important features that predicts stroke outcome.•The follow-up data is important which can further improve the predictive models’ performance.•Error analysis shows that most prediction errors come from more severe stroke patients.
Being able to predict functional outcomes after a stroke is highly desirable for clinicians. This allows clinicians to set reasonable goals with patients and relatives, and to reach shared after-care decisions for recovery or rehabilitation. The aim of this study was to apply various machine learning (ML) methods for 90-day stroke outcome predictions, using a nationwide disease registry.
This study used the Taiwan Stroke Registry (TSR) which has prospectively collected data from stroke patients since 2006. Three known ML models (support vector machine, random forest, and artificial neural network), and a hybrid artificial neural network were implemented and evaluated by 10-time repeated hold-out with 10-fold cross-validation.
ML techniques present over 0.94 AUC in both ischemic and hemorrhagic stroke using preadmission and inpatient data. By adding follow-up data, the prediction ability improved to 0.97 AUC. We screened 206 clinical variables to identify 17 important features from the ischemic stroke dataset and 22 features from the hemorrhagic stroke dataset without losing much performance. Error analysis revealed that most prediction errors come from more severe stroke patients.
The study showed that ML techniques trained from large, cross-reginal registry datasets were able to predict functional outcome after stroke with high accuracy. The follow-up data is important which can further improve the predictive models’ performance. With similar performances among different ML techniques, the algorithm's characteristics and performance on severe stroke patients will be the primary focus when we further develop inference models and artificial intelligence tools for potential medical.
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Platelet activation is involved in cardiovascular diseases, such as atherosclerosis and ischemic stroke. Licochalcone A (LA), an active ingredient of licorice, exhibits multiple biological activities ...such as anti-oxidation and anti-inflammation. However, its role in platelet activation remains unclear. Therefore, the study investigated the antiplatelet mechanism of LA. Our data revealed that LA (2-10 μM) concentration dependently inhibited platelet aggregation induced by collagen, but not thrombin and U46619. LA markedly attenuated collagen-stimulated ATP release, P-selectin secretion, calcium mobilization, and GPIIbIIIa activation, but did not interfere with the collagen binding to platelets. Moreover, LA significantly reduced the activation of PLCγ2, PKC, Akt and MAPKs. Thus, LA attenuates platelet activation, possibly by inhibiting collagen receptor downstream signaling but not by blocking the collagen receptors. In addition, LA prevented adenosine diphosphate (ADP)-induced acute pulmonary thrombosis, fluorescein sodium-induced platelet thrombus formation, and middle cerebral artery occlusion/reperfusion-induced brain injury in mice, but did not affect normal hemostasis. This study demonstrated that LA effectively reduced platelet activation and thrombus formation, in part, through the inhibition of PLCγ2-PKC, Akt, and MAPK pathways, without the side effect of bleeding. These findings also indicate that LA may provide a safe and alternative therapeutic approach for preventing thromboembolic disorders such as stroke.
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