Dual Antiplatelet Treatment up to 72 Hours after Ischemic Stroke.

BACKGROUND: Dual antiplatelet treatment has been shown to lower the risk of recurrent stroke as compared with aspirin alone when treatment is initiated early (≤24 hours) after an acute mild stroke. The effect of clopidogrel plus aspirin as compared with aspirin alone administered within 72 hours after the onset of acute cerebral ischemia from atherosclerosis has not been well studied. METHODS: In 222 hospitals in China, we conducted a double-blind, randomized, placebo-controlled, two-by-two factorial trial involving patients with mild ischemic stroke or high-risk transient ischemic attack (TIA) of presumed atherosclerotic cause who had not undergone thrombolysis or thrombectomy. Patients were randomly assigned, in a 1:1 ratio, within 72 hours after symptom onset to receive clopidogrel (300 mg on day 1 and 75 mg daily on days 2 to 90) plus aspirin (100 to 300 mg on day 1 and 100 mg daily on days 2 to 21) or matching clopidogrel placebo plus aspirin (100 to 300 mg on day 1 and 100 mg daily on days 2 to 90). There was no interaction between this component of the factorial trial design and a second part that compared immediate with delayed statin treatment (not reported here). The primary efficacy outcome was new stroke, and the primary safety outcome was moderate-to-severe bleeding - both assessed within 90 days. RESULTS: A total of 6100 patients were enrolled, with 3050 assigned to each trial group. TIA was the qualifying event for enrollment in 13.1% of the patients. A total of 12.8% of the patients were assigned to a treatment group no more than 24 hours after stroke onset, and 87.2% were assigned after 24 hours and no more than 72 hours after stroke onset. A new stroke occurred in 222 patients (7.3%) in the clopidogrel-aspirin group and in 279 (9.2%) in the aspirin group (hazard ratio, 0.79; 95% confidence interval [CI], 0.66 to 0.94; P = 0.008). Moderate-to-severe bleeding occurred in 27 patients (0.9%) in the clopidogrel-aspirin group and in 13 (0.4%) in the aspirin group (hazard ratio, 2.08; 95% CI, 1.07 to 4.04; P = 0.03). CONCLUSIONS: Among patients with mild ischemic stroke or high-risk TIA of presumed atherosclerotic cause, combined clopidogrel-aspirin therapy initiated within 72 hours after stroke onset led to a lower risk of new stroke at 90 days than aspirin therapy alone but was associated with a low but higher risk of moderate-to-severe bleeding. (Funded by the National Natural Science Foundation of China and others; INSPIRES ClinicalTrials.gov number, NCT03635749.).

Real-time pandemic surveillance using hospital admissions and mobility data.

Forecasting the burden of COVID-19 has been impeded by limitations in data, with case reporting biased by testing practices, death counts lagging far behind infections, and hospital census reflecting time-varying patient access, admission criteria, and demographics. Here, we show that hospital admissions coupled with mobility data can reliably predict severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission rates and healthcare demand. Using a forecasting model that has guided mitigation policies in Austin, TX, we estimate that the local reproduction number had an initial 7-d average of 5.8 (95% credible interval [CrI]: 3.6 to 7.9) and reached a low of 0.65 (95% CrI: 0.52 to 0.77) after the summer 2020 surge. Estimated case detection rates ranged from 17.2% (95% CrI: 11.8 to 22.1%) at the outset to a high of 70% (95% CrI: 64 to 80%) in January 2021, and infection prevalence remained above 0.1% between April 2020 and March 1, 2021, peaking at 0.8% (0.7-0.9%) in early January 2021. As precautionary behaviors increased safety in public spaces, the relationship between mobility and transmission weakened. We estimate that mobility-associated transmission was 62% (95% CrI: 52 to 68%) lower in February 2021 compared to March 2020. In a retrospective comparison, the 95% CrIs of our 1, 2, and 3 wk ahead forecasts contained 93.6%, 89.9%, and 87.7% of reported data, respectively. Developed by a task force including scientists, public health officials, policy makers, and hospital executives, this model can reliably project COVID-19 healthcare needs in US cities.

Baseline Stroke Risk and Efficacy of Dual-Antiplatelet Therapy: A Post Hoc Analysis of the POINT Trial.

BACKGROUND: High-risk transient ischemic attacks and minor ischemic strokes are followed by a variable risk of ischemic stroke. We aimed to determine how baseline stroke risk modified the efficacy of clopidogrel-aspirin (referred to here as dual-antiplatelet therapy [DAPT]) for transient ischemic attack and minor ischemic stroke. METHODS: We performed an unplanned secondary analysis of the POINT trial (Platelet-Oriented Inhibition in New Transient Ischemic Attack and Minor Ischemic Stroke). We first evaluated the associations of the CHA2DS2-VASc and stroke prognosis instrument II (SPI-II) scores with the risk of incident ischemic stroke and major hemorrhage (intracranial hemorrhage or major systemic hemorrhage). We then tested for heterogeneity of the relative and absolute treatment effect of DAPT relative to aspirin across low- and high-risk patient subgroups. RESULTS: A total of 4841 trial participants were included in this analysis, with 2400 participants assigned to treatment with short-term DAPT and 2430 participants to treatment with aspirin and placebo. The dichotomized SPI-II score, but not the CHA2DS2-VASc score (P=0.18), was associated with the risk of incident ischemic stroke. A high-risk SPI-II score (>3) was associated with greater risk of incident ischemic stroke (hazard ratio of incident ischemic stroke relative to low-risk SPI-II score of 1.84 [95% CI, 1.44-2.35]; P<0.001) and numerically greater risk of major hemorrhage though not meeting statistical significance (hazard ratio, 1.80 [95% CI, 0.90-3.57]; P=0.10). The relative risk reduction with DAPT was similar across SPI-II strata (Pinteraction=0.31). The absolute risk reduction for ischemic stroke with DAPT compared with aspirin was nearly 4-fold higher (2.80% versus 0.76%; number needed to treat, 31 versus 131) in the high-risk SPI-II stratum relative to the low-risk stratum. The absolute risk increase for major hemorrhage with DAPT compared with aspirin was 3-fold higher (0.84% versus 0.30%; number needed to harm, 119 versus 331) in the high-risk SPI-II stratum relative to the low-risk stratum. CONCLUSIONS: Stratification by baseline stroke risk identifies a patient subgroup that derives greater absolute benefit from treatment with DAPT. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00991029.

Dual Antiplatelet Therapy After Embolic Stroke of Undetermined Source: A Subgroup Analysis of the CHANCE-2 Trial.

BACKGROUND: The atherosclerotic sources of embolism are a significant contributor to embolic stroke of undetermined source (ESUS). However, there is limited evidence for the efficacy of intensive dual antiplatelet therapy for ESUS. We conducted an investigation to determine whether gene-directed dual antiplatelet therapy could reduce the risk of recurrent stroke in patients with ESUS. METHODS: CHANCE-2 (Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events-II) was an investigator-initiated, multicenter, randomized, double-blind, placebo-controlled trial that objectively compared ticagrelor plus aspirin and clopidogrel plus aspirin in patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles in China. All study participants were classified into ESUS and non-ESUS groups for the prespecified exploratory analysis. Cox proportional hazards models were used to assess the interaction of the state of ESUS with the effects of dual antiplatelet therapy with ticagrelor-aspirin versus clopidogrel-aspirin, adjusting for sociodemographic and clinical factors. RESULTS: The subgroup analysis comprised 5796 participants (90.4% of the total 6412 participants) in the CHANCE-2 trial, with a median age of 64.9 years (range, 57.0-71.4 years), of whom 1964 (33.9%) were female. These participants underwent diffusion-weighted imaging as part of the study protocol. After systematic evaluation, 15.2% of patients (881/5796) were deemed to have ESUS. The incidence of stroke recurrence in patients with ESUS was found to be 5.6% in the ticagrelor-aspirin group and 9.2% in the clopidogrel-aspirin group (hazard ratio, 0.57 [95% CI, 0.33-0.99]; P=0.04). In patients without ESUS, the respective incidence rates were 5.6% and 7.5% (hazard ratio, 0.72 [95% CI, 0.58-0.90]; P<0.01). The P value was 0.56 for the treatment × ESUS status interaction effect. CONCLUSIONS: In this prespecified exploratory analysis, ticagrelor with aspirin was superior to clopidogrel with aspirin for preventing stroke at 90 days in patients with acute ischemic stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles and were classified as ESUS. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04078737.

Ticagrelor versus Clopidogrel in CYP2C19 Loss-of-Function Carriers with Stroke or TIA.

BACKGROUND: Comparisons between ticagrelor and clopidogrel for the secondary prevention of stroke in CYP2C19 loss-of-function carriers have not been extensively performed. METHODS: We conducted a randomized, double-blind, placebo-controlled trial at 202 centers in China involving patients with a minor ischemic stroke or transient ischemic attack (TIA) who carried CYP2C19 loss-of-function alleles. Patients were assigned within 24 hours after symptom onset, in a 1:1 ratio, to receive ticagrelor (180 mg on day 1 followed by 90 mg twice daily on days 2 through 90) and placebo clopidogrel or to receive clopidogrel (300 mg on day 1 followed by 75 mg once daily on days 2 through 90) and placebo ticagrelor; both groups received aspirin for 21 days. The primary efficacy outcome was new stroke, and the primary safety outcome was severe or moderate bleeding, both within 90 days. RESULTS: A total of 11,255 patients were screened and 6412 patients were enrolled, with 3205 assigned to the ticagrelor group and 3207 to the clopidogrel group. The median age of the patients was 64.8 years, and 33.8% were women; 98.0% belonged to the Han Chinese ethnic group. Stroke occurred within 90 days in 191 patients (6.0%) in the ticagrelor group and 243 patients (7.6%) in the clopidogrel group (hazard ratio, 0.77; 95% confidence interval, 0.64 to 0.94; P = 0.008). Secondary outcomes were generally in the same direction as the primary outcome. Severe or moderate bleeding occurred in 9 patients (0.3%) in the ticagrelor group and in 11 patients (0.3%) in the clopidogrel group; any bleeding occurred in 170 patients (5.3%) and 80 patients (2.5%), respectively. CONCLUSIONS: Among Chinese patients with minor ischemic stroke or TIA who were carriers of CYP2C19 loss-of-function alleles, the risk of stroke at 90 days was modestly lower with ticagrelor than with clopidogrel. The risk of severe or moderate bleeding did not differ between the two treatment groups, but ticagrelor was associated with more total bleeding events than clopidogrel. (Funded by the Ministry of Science and Technology of the People's Republic of China and others; CHANCE-2 ClinicalTrials.gov number, NCT04078737.).

Abemaciclib plus a nonsteroidal aromatase inhibitor as initial therapy for HR+, HER2- advanced breast cancer: final overall survival results of MONARCH 3.

BACKGROUND: In MONARCH 2, the addition of abemaciclib to fulvestrant significantly improved both progression-free survival (PFS) and overall survival (OS) in patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) with disease progression on prior endocrine therapy. In MONARCH 3, the addition of abemaciclib to a nonsteroidal aromatase inhibitor (NSAI) as initial therapy for HR+, HER2- ABC significantly improved PFS. Here, we present the prespecified final OS results for MONARCH 3. PATIENTS AND METHODS: MONARCH 3 is a randomized, double-blind, phase III study of abemaciclib plus NSAI (anastrozole or letrozole) versus placebo plus NSAI in postmenopausal women with HR+, HER2- ABC without prior systemic therapy in the advanced setting. The primary objective was investigator-assessed PFS; OS was a gated secondary endpoint, and chemotherapy-free survival was an exploratory endpoint. RESULTS: A total of 493 women were randomized 2 : 1 to receive abemaciclib plus NSAI (n = 328) or placebo plus NSAI (n = 165). After a median follow-up of 8.1 years, there were 198 OS events (60.4%) in the abemaciclib arm and 116 (70.3%) in the placebo arm (hazard ratio, 0.804; 95% confidence interval 0.637-1.015; P = 0.0664, non-significant). Median OS was 66.8 versus 53.7 months for abemaciclib versus placebo. In the subgroup with visceral disease, there were 113 OS events (65.3%) in the abemaciclib arm and 65 (72.2%) in the placebo arm (hazard ratio, 0.758; 95% confidence interval 0.558-1.030; P = 0.0757, non-significant). Median OS was 63.7 months versus 48.8 months for abemaciclib versus placebo. The previously demonstrated PFS benefit was sustained, and chemotherapy-free survival numerically improved with the addition of abemaciclib. No new safety signals were observed. CONCLUSIONS: Abemaciclib combined with an NSAI resulted in clinically meaningful improvement in median OS (intent-to-treat population: 13.1 months; subgroup with visceral disease: 14.9 months) in patients with HR+ HER2- ABC; however, statistical significance was not reached.

Multicolumn Nanoflow Liquid Chromatography with Accelerated Offline Gradient Generation for Robust and Sensitive Single-Cell Proteome Profiling.

Peptide separations that combine high sensitivity, robustness, peak capacity, and throughput are essential for extending bottom-up proteomics to smaller samples including single cells. To this end, we have developed a multicolumn nanoLC system with offline gradient generation. One binary pump generates gradients in an accelerated fashion to support multiple analytical columns, and a single trap column interfaces with all analytical columns to reduce required maintenance and simplify troubleshooting. A high degree of parallelization is possible, as one sample undergoes separation while the next sample plus its corresponding mobile phase gradient are transferred into the storage loop and a third sample is loaded into a sample loop. Selective offline elution from the trap column into the sample loop prevents salts and hydrophobic species from entering the analytical column, thus greatly enhancing column lifetime and system robustness. With this design, samples can be analyzed as fast as every 20 min at a flow rate of just 40 nL/min with close to 100% MS utilization time and continuously for as long as several months without column replacement. We utilized the system to analyze the proteomes of single cells from a multiple myeloma cell line upon treatment with the immunomodulatory imide drug lenalidomide.

Milvexian vs apixaban for stroke prevention in atrial fibrillation: The LIBREXIA atrial fibrillation trial rationale and design.

BACKGROUND: Direct oral anticoagulants are the standard of care for stroke prevention in eligible patients with atrial fibrillation and atrial flutter; however, bleeding remains a significant concern, limiting their use. Milvexian is an oral Factor XIa inhibitor that may offer similar anticoagulant efficacy with less bleeding risk. METHODS: LIBREXIA AF (NCT05757869) is a global phase III, randomized, double-blind, parallel-group, event-driven trial to compare milvexian with apixaban in participants with atrial fibrillation or atrial flutter. Participants are randomly assigned to milvexian 100 mg or apixaban (5 mg or 2.5 mg per label indication) twice daily. The primary efficacy objective is to evaluate if milvexian is noninferior to apixaban for the prevention of stroke and systemic embolism. The principal safety objective is to evaluate if milvexian is superior to apixaban in reducing the endpoint of International Society of Thrombosis and Hemostasis (ISTH) major bleeding events and the composite endpoint of ISTH major and clinically relevant nonmajor (CRNM) bleeding events. In total, 15,500 participants from approximately 1,000 sites in over 30 countries are planned to be enrolled. They will be followed until both 430 primary efficacy outcome events and 530 principal safety events are observed, which is estimated to take approximately 4 years. CONCLUSION: The LIBREXIA AF study will determine the efficacy and safety of the oral Factor XIa inhibitor milvexian compared with apixaban in participants with either atrial fibrillation or atrial flutter. TRIAL REGISTRATION: ClinicalTrials.gov NCT05757869.

Genotype-Guided Dual Antiplatelet Use for Transient Ischemic Attack and Minor Stroke by Imaging Status: Subgroup Analysis of the CHANCE-2 Trial.

OBJECTIVE: This study was performed to investigate whether ticagrelor/aspirin versus clopidogrel/aspirin can further reduce the residual risk of stroke recurrence in patients with positive diffusion-weighted imaging (DWI) in the High-Risk Patients with Acute Nondisabling Cerebrovascular Events II (CHANCE-2) trial. METHODS: Patients with DWI data in the CHANCE-2 trial were included and divided into those with and without acute infarction according to their DWI findings. The primary efficacy outcome and safety outcome were stroke recurrence and moderate to severe bleeding within 3 months of follow-up, respectively. RESULTS: Of the 6,412 patients enrolled in the CHANCE-2 trial, 5,796 (90.4%) patients with DWI data were included in the subgroup analysis. A total of 4,369 patients (75.4%) had an acute infarction on DWI. Patients with positive DWI had higher risk of recurrent stroke (8.1%) than those without infarction (2.2%) within 3-month follow-up. Compared with clopidogrel/aspirin, ticagrelor/aspirin was associated with lower risk of stroke in patients with positive DWI (hazard ratio [HR] = 0.65, 95% confidence interval [CI] = 0.52-0.80, p < 0.001) than in those negative DWI (HR = 1.22, 95% CI = 0.55-2.72, p = 0.63), with a significant interaction association (p for interaction = 0.049). The risk of moderate to severe bleeding was similar between ticagrelor/aspirin and clopidogrel/aspirin treatment in the different groups. INTERPRETATION: Our study demonstrates that imaging evaluation should be emphasized before targeting the best candidates for genotype-guided dual antiplatelet therapy in future clinical research and practice. ANN NEUROL 2023;93:783-792.

Time to treatment and disability attributed to index stroke in the POINT trial.

BACKGROUND: In the Platelet-Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) trial, dual antiplatelet therapy (DAPT) was associated with reduced disability attributable to the index stroke compared to antiplatelet monotherapy. However, it is unknown whether earlier treatment with DAPT versus aspirin is associated with greater benefit. METHODS: We analyzed patients enrolled in POINT with minor ischemic stroke who had available data recording the treatment initiation time and modified Rankin Scale (mRS) at 90 days. Patients were randomized to DAPT (aspirin plus clopidogrel) vs. aspirin alone within 12 h of symptom onset. We estimated the effect of DAPT on disability (defined as mRS>1) ascribed to the index event and major hemorrhage at 90 days, stratified by tertiles of time from symptom onset-to-treatment-initiation. RESULTS: A total of 2559 patients were included; median onset-to-treatment-initiation time was 8.3 h (IQR:5.8-11.0). Comparing DAPT to aspirin, the rate of disability attributed to the index event at 90-day follow-up was 5.1 % vs. 8.6 % (OR 0.57; 95 % CI:0.33-0.99) in patients treated <6.7 h, 7.5 % vs. 9.9 % (OR 0.74; 95 % CI:0.45-1.19) in those treated 6.7-10.0 h, and 8.6 % vs. 10.6 % (OR 0.80; 95 % CI:0.50-1.26) in those treated >10.0 h after symptom onset (p for interaction=0.65). There was no difference in major hemorrhage across time strata. CONCLUSIONS: While not statistically significant, these results suggest the possibility of greater efficacy at reducing disability ascribed to minor stroke with earlier treatment with DAPT compared to aspirin. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Identifier: NCT00991029.

Diagnosis, Workup, Risk Reduction of Transient Ischemic Attack in the Emergency Department Setting: A Scientific Statement From the American Heart Association.

At least 240 000 individuals experience a transient ischemic attack each year in the United States. Transient ischemic attack is a strong predictor of subsequent stroke. The 90-day stroke risk after transient ischemic attack can be as high as 17.8%, with almost half occurring within 2 days of the index event. Diagnosing transient ischemic attack can also be challenging given the transitory nature of symptoms, often reassuring neurological examination at the time of evaluation, and lack of confirmatory testing. Limited resources, such as imaging availability and access to specialists, can further exacerbate this challenge. This scientific statement focuses on the correct clinical diagnosis, risk assessment, and management decisions of patients with suspected transient ischemic attack. Identification of high-risk patients can be achieved through use of comprehensive protocols incorporating acute phase imaging of both the brain and cerebral vasculature, thoughtful use of risk stratification scales, and ancillary testing with the ultimate goal of determining who can be safely discharged home from the emergency department versus admitted to the hospital. We discuss various methods for rapid yet comprehensive evaluations, keeping resource-limited sites in mind. In addition, we discuss strategies for secondary prevention of future cerebrovascular events using maximal medical therapy and patient education.

Dual Antiplatelet Therapies and Causes in Minor Stroke or Transient Ischemic Attack: A Prespecified Analysis in the CHANCE-2 Trial.

BACKGROUND: It is unclear whether patients with different stroke/transient ischemic attack etiologies benefit differently from gene-directed dual antiplatelet therapy. This study explored the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin in transient ischemic attack or minor stroke with different causes in the CHANCE-2 trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events-II). METHODS: This was a prespecified analysis of the CHANCE-2 trial, which enrolled 6412 patients with minor stroke or transient ischemic attack who carried CYP2C19 loss-of-function alleles. Patients with centralized evaluation of TOAST (Trial of ORG 10172 in Acute Stroke Treatment) classification of large-artery atherosclerosis, small-vessel occlusion, and stroke of undetermined cause were included. The primary efficacy outcome was new stroke, and the primary safety outcome was severe or moderate bleeding, both within 90 days. Cox proportional hazards models were used to assess the interaction of TOAST classification with the effects of dual antiplatelet therapy with ticagrelor-aspirin versus clopidogrel-aspirin. RESULTS: A total of 6336 patients were included in this study. In patients administered ticagrelor-aspirin and clopidogrel-aspirin, respectively, stroke recurred in 85 (9.8%) and 88 (10.7%) patients with large-artery atherosclerosis (hazard ratio, 0.86 [95% CI, 0.63-1.18]; P=0.34); 32 (3.6%) and 61 (7.0%) patients with small-vessel occlusion (hazard ratio, 0.51 [95% CI, 0.33-0.79]; P=0.002); and 68 (4.8%) and 87 (5.9%) patients with stroke of undetermined cause (hazard ratio, 0.80 [95% CI, 0.58-1.10]; P=0.17), with P=0.08 for the treatment×cause subtype interaction effect. There were no significant differences in severe or moderate bleeding events in patients with different cause and different treatment. CONCLUSIONS: In this prespecified analysis of the CHANCE-2 trial, the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin in preventing new stroke were consistent in patients with different causes. The influence of stroke cause on benefit of gene-guided antiplatelet therapy should be explored by further trials. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04078737.

Ticagrelor and Aspirin or Aspirin Alone in Acute Ischemic Stroke or TIA.

BACKGROUND: Trials have evaluated the use of clopidogrel and aspirin to prevent stroke after an ischemic stroke or transient ischemic attack (TIA). In a previous trial, ticagrelor was not better than aspirin in preventing vascular events or death after stroke or TIA. The effect of the combination of ticagrelor and aspirin on prevention of stroke has not been well studied. METHODS: We conducted a randomized, placebo-controlled, double-blind trial involving patients who had had a mild-to-moderate acute noncardioembolic ischemic stroke, with a National Institutes of Health Stroke Scale (NIHSS) score of 5 or less (range, 0 to 42, with higher scores indicating more severe stroke), or TIA and who were not undergoing thrombolysis or thrombectomy. The patients were assigned within 24 hours after symptom onset, in a 1:1 ratio, to receive a 30-day regimen of either ticagrelor (180-mg loading dose followed by 90 mg twice daily) plus aspirin (300 to 325 mg on the first day followed by 75 to 100 mg daily) or matching placebo plus aspirin. The primary outcome was a composite of stroke or death within 30 days. Secondary outcomes were first subsequent ischemic stroke and the incidence of disability within 30 days. The primary safety outcome was severe bleeding. RESULTS: A total of 11,016 patients underwent randomization (5523 in the ticagrelor-aspirin group and 5493 in the aspirin group). A primary-outcome event occurred in 303 patients (5.5%) in the ticagrelor-aspirin group and in 362 patients (6.6%) in the aspirin group (hazard ratio, 0.83; 95% confidence interval [CI], 0.71 to 0.96; P = 0.02). Ischemic stroke occurred in 276 patients (5.0%) in the ticagrelor-aspirin group and in 345 patients (6.3%) in the aspirin group (hazard ratio, 0.79; 95% CI, 0.68 to 0.93; P = 0.004). The incidence of disability did not differ significantly between the two groups. Severe bleeding occurred in 28 patients (0.5%) in the ticagrelor-aspirin group and in 7 patients (0.1%) in the aspirin group (P = 0.001). CONCLUSIONS: Among patients with a mild-to-moderate acute noncardioembolic ischemic stroke (NIHSS score ≤5) or TIA who were not undergoing intravenous or endovascular thrombolysis, the risk of the composite of stroke or death within 30 days was lower with ticagrelor-aspirin than with aspirin alone, but the incidence of disability did not differ significantly between the two groups. Severe bleeding was more frequent with ticagrelor. (Funded by AstraZeneca; THALES ClinicalTrial.gov number, NCT03354429.).

Bleeding Risk of Dual Antiplatelet Therapy after Minor Stroke or Transient Ischemic Attack.

OBJECTIVE: This study was undertaken to identify the risk of bleeding events and potential risk factors within 90 days in patients who carried CYP2C19 loss-of-function alleles and received dual antiplatelet therapy after minor stroke or transient ischemic attack. METHODS: A total of 6,412 patients were enrolled from the CHANCE-2 (Clopidogrel with Aspirin in High-Risk Patients with Acute Non-disabling Cerebrovascular Events II) trial. The main outcome was any bleeding within 90 days defined by the criteria from GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries). RESULTS: A total of 250 (3.9%) bleeding events were reported, which occurred mainly within the 21 days of dual antiplatelet therapy (200 cases, 3.1%). Minor bleeding of the skin bruises, epistaxis, and gum bleeding were most frequent. Multivariate analysis showed that treatment with ticagrelor-aspirin compared with clopidogrel-aspirin was associated with increased bleeding (hazard ratio [HR] = 2.21, 95% confidence interval [CI] = 1.68-2.89, p < 0.001). Current smoking was associated with a lower risk of bleeding (HR = 0.70, 95% CI = 0.52-0.95, p = 0.02). Additionally, ticagrelor-aspirin compared with clopidogrel-aspirin was associated with higher risk of bleeding in patients aged <65 years (HR = 2.87, 95% CI = 1.95-4.22) and those without diabetes mellitus (HR = 2.65, 95% CI = 1.88-3.73; p for interaction = 0.04 and 0.03, respectively). INTERPRETATION: Bleeding events mostly occurred within the 21-day dual antiplatelet therapy stage and were generally mild. The risk of bleeding was greater in nonsmoking patients, and was associated with treatment with ticagrelor-aspirin compared with clopidogrel-aspirin, particularly in patients aged <65 years and nondiabetic patients. ANN NEUROL 2022;91:380-388.

m2ABQ-a proposed refinement of the modified algorithm-based qualitative classification of osteoporotic vertebral fractures.

Currently, there is no reproducible, widely accepted gold standard to classify osteoporotic vertebral body fractures (OVFs). The purpose of this study is to refine a method with clear rules to classify OVFs for machine learning purposes. The method was found to have moderate interobserver agreement that improved with training. INTRODUCTION: The current methods to classify osteoporotic vertebral body fractures are considered ambiguous; there is no reproducible, accepted gold standard. The purpose of this study is to refine classification methodology by introducing clear, unambiguous rules and a refined flowchart to allow consistent classification of osteoporotic vertebral body fractures. METHODS: We developed a set of rules and refinements that we called m2ABQ to classify vertebrae into five categories. A fracture-enriched database of thoracic and lumbar spine radiographs of patients 65 years of age and older was retrospectively obtained from clinical institutional radiology records using natural language processing. Five raters independently classified each vertebral body using the m2ABQ system. After each annotation round, consensus sessions that included all raters were held to discuss and finalize a consensus annotation for each vertebral body where individual raters' evaluations differed. This process led to further refinement and development of the rules. RESULTS: Each annotation round showed increase in Fleiss kappa both for presence vs absence of fracture 0.62 (0.56-0.68) to 0.70 (0.65-0.75), as well as for the whole m2ABQ scale 0.29 (0.25-0.33) to 0.54 (0.51-0.58). CONCLUSION: The m2ABQ system demonstrates moderate interobserver agreement and practical feasibility for classifying osteoporotic vertebral body fractures. Future studies to compare the method to existing studies are warranted, as well as further development of its use in machine learning purposes.

Ticagrelor-Aspirin Versus Clopidogrel-Aspirin Among CYP2C19 Loss-of-Function Carriers With Minor Stroke or Transient Ischemic Attack in Relation to Renal Function: A Post Hoc Analysis of the CHANCE-2 Trial.

BACKGROUND: Evidence on the risk-benefit ratio of dual antiplatelet therapies among patients with stroke and impaired renal function is limited and inconsistent. OBJECTIVE: To investigate the effect of renal function on the efficacy and safety of ticagrelor-aspirin versus clopidogrel-aspirin treatment. DESIGN: Post hoc analysis of a multicenter, randomized, double-blind, placebo-controlled trial. (ClinicalTrials.gov: NCT04078737). SETTING: 202 centers in China. PATIENTS: CYP2C19 loss-of-function allele carriers with minor stroke or transient ischemic attack. INTERVENTION: Ticagrelor-aspirin and clopidogrel-aspirin. MEASUREMENTS: Renal function was evaluated by estimated glomerular filtration rate (eGFR) levels. The primary efficacy and safety outcomes were recurrent stroke and severe or moderate bleeding within 90 days, respectively. RESULTS: Among 6378 patients, 4050 (63.5%) had normal (eGFR ≥90 mL/min/1.73 m2), 2010 (31.5%) had mildly decreased (eGFR 60 to 89 mL/min/1.73 m2), and 318 (5.0%) had moderately to severely decreased (eGFR <60 mL/min/1.73 m2) renal function. The corresponding differences in recurrent stroke between ticagrelor-aspirin and clopidogrel-aspirin for normal, mildly decreased, and moderately to severely decreased renal function was -2.8 percentage points (95% CI, -4.4 to -1.3 percentage points) (hazard ratio [HR], 0.63 [CI, 0.49 to 0.81]), -0.2 percentage point (CI, -2.4 to 2.0 percentage points) (HR, 0.98 [CI, 0.69 to 1.39]), and 3.7 percentage points (CI, -2.3 to 10.1 percentage points) (HR, 1.31 [CI, 0.48 to 3.55]), respectively. Rates of severe or moderate bleeding did not substantially differ by treatment assignments across eGFR categories. LIMITATION: Renal function was only evaluated by using eGFR, and the proportion of patients with severely decreased renal function was low. CONCLUSION: Patients with normal, rather than impaired, renal function received greater benefit from ticagrelor-aspirin versus clopidogrel-aspirin. PRIMARY FUNDING SOURCE: Ministry of Science and Technology of the People's Republic of China.

Variation and genetic control of individual recombination rates in Norwegian Red dairy cattle.

Meiotic recombination is an important evolutionary mechanism that breaks up linkages between loci and creates novel haplotypes for selection to act upon. Understanding the genetic control of variation in recombination rates is therefore of great interest in both natural and domestic breeding populations. In this study, we used pedigree information and medium-density (∼50K) genotyped data in a large cattle (Bos taurus) breeding population in Norway (Norwegian Red cattle) to investigate recombination rate variation between sexes and individual animals. Sex-specific linkage mapping showed higher rates in males than in females (total genetic length of autosomes = 2,492.9 cM in males and 2,308.9 cM in females). However, distribution of recombination along the genome showed little variation between males and females compared with that in other species. The heritability of autosomal crossover count was low but significant in both sexes (h2 = 0.04 and 0.09 in males and females, respectively). We identified 2 loci associated with variation in individual crossover counts in female, one close to the candidate gene CEP55 and one close to both MLH3 and NEK9. All 3 genes have been associated with recombination rates in other cattle breeds. Our study contributes to the understanding of how recombination rates are controlled and how they may vary between closely related breeds as well as between species.

Data-Dependent Acquisition with Precursor Coisolation Improves Proteome Coverage and Measurement Throughput for Label-Free Single-Cell Proteomics.

We combined efficient sample preparation and ultra-low-flow liquid chromatography with a newly developed data acquisition and analysis scheme termed wide window acquisition (WWA) to quantify >3,000 proteins from single cells in rapid label-free analyses. WWA employs large isolation windows to intentionally co-isolate and co-fragment adjacent precursors along with the selected precursor. Optimized WWA increased the number of MS2-identified proteins by ≈40 % relative to standard data-dependent acquisition. For a 40-min LC gradient operated at ≈15 nL/min, we identified an average of 3,524 proteins per single-cell-sized aliquot of protein digest. Reducing the active gradient to 20 min resulted in a modest 10 % decrease in proteome coverage. Using this platform, we compared protein expression between single HeLa cells having an essential autophagy gene, atg9a, knocked out, with their isogenic WT parental line. Similar proteome coverage was observed, and 268 proteins were significantly up- or downregulated. Protein upregulation primarily related to innate immunity, vesicle trafficking and protein degradation.

Features of Peptide Fragmentation Spectra in Single-Cell Proteomics.

The goal of proteomics is to identify and quantify the complete set of proteins in a biological sample. Single-cell proteomics specializes in the identification and quantitation of proteins for individual cells, often used to elucidate cellular heterogeneity. The significant reduction in ions introduced into the mass spectrometer for single-cell samples could impact the features of MS2 fragmentation spectra. As all peptide identification software tools have been developed on spectra from bulk samples and the associated ion-rich spectra, the potential for spectral features to change is of great interest. We characterize the differences between single-cell spectra and bulk spectra by examining three fundamental spectral features that are likely to affect peptide identification performance. All features show significant changes in single-cell spectra, including the loss of annotated fragment ions, blurring signal and background peaks due to diminishing ion intensity, and distinct fragmentation pattern, compared to bulk spectra. As each of these features is a foundational part of peptide identification algorithms, it is critical to adjust algorithms to compensate for these losses.

In-Depth Mass Spectrometry-Based Proteomics of Formalin-Fixed, Paraffin-Embedded Tissues with a Spatial Resolution of 50-200 µm.

Formalin-fixed, paraffin-embedded (FFPE) tissues are banked in large repositories to cost-effectively preserve valuable specimens for later study. With the rapid growth of spatial proteomics, FFPE tissues can serve as a more accessible alternative to more commonly used frozen tissues. However, extracting proteins from FFPE tissues is challenging due to cross-links formed between proteins and formaldehyde. Here, we have adapted the nanoPOTS sample processing workflow, which was previously applied to single cells and fresh-frozen tissues, to profile protein expression from FFPE tissues. Following the optimization of extraction solvents, times, and temperatures, we identified an average of 1312 and 3184 high-confidence master proteins from 10 µm thick FFPE-preserved mouse liver tissue squares having lateral dimensions of 50 and 200 µm, respectively. The observed proteome coverage for FFPE tissues was on average 88% of that achieved for similar fresh-frozen tissues. We also characterized the performance of our fully automated sample preparation and analysis workflow, termed autoPOTS, for FFPE spatial proteomics. This modified nanodroplet processing in one pot for trace samples (nanoPOTS) and fully automated processing in one pot for trace sample (autoPOTS) workflows provides the greatest coverage reported to date for high-resolution spatial proteomics applied to FFPE tissues. Data are available via ProteomeXchange with identifier PXD029729.