RESUMEN
Laser wakefield acceleration is paving the way for the next generation of electron accelerators, for their own sake and as radiation sources. A controllable dual-wake injection scheme is put forward here to generate an ultrashort triplet electron bunch with high brightness and high polarization, employing a radially polarized laser as a driver. We find that the dual wakes can be driven by both transverse and longitudinal components of the laser field in the quasiblowout regime, sustaining the laser-modulated wakefield which facilitates the subcycle and transversely split injection of the triplet bunch. Polarization of the triplet bunch can be highly preserved due to the laser-assisted collective spin precession and the noncanceled transverse spins. In our three-dimensional particle-in-cell simulations, the triplet electron bunch, with duration about 500 as, six-dimensional brightness exceeding 10^{14} A/m^{2}/0.1% and polarization over 80%, can be generated using a few-terawatt laser. Such an electron bunch could play an essential role in many applications, such as ultrafast imaging, nuclear structure and high-energy physics studies, and the operation of coherent radiation sources.
RESUMEN
BACKGROUND: The use of Alteplase (ALT) bridging to endovascular mechanical thrombectomy (MT) has become the standard approach in treating patients with large vessel stroke (LVO). Tenecteplase (TNK) has emerged as an equivalent fibrinolytic agent in treating ischemic stroke due to its remarkable pharmacological characteristics. This study aims to compare the use of intravenous TNK to ALT bridging to MT in patients with LVO. METHODS: We included observational and randomized controlled trials of patients with LVO who received bridging TNK vs ALT before undergoing MT. Efficacy outcomes included functional independence which is indicated by a modified Rankin Scale [mRS] score of 0-2 at 90 days. Radiological outcomes included the rate of successful recanalization post-MT (Modified Treatment in Cerebral Ischemia [mTICI] score of 2b/3), and the rate of pre-MT recanalization, indicated by an mTICI of 2b/3 at the first angiographic assessment. The all-cause mortality at 90 days (mRS of 6) was considered the primary safety outcome, while the symptomatic intracranial hemorrhage (sICH) rate was reported as an adverse event. RESULTS: We identified 5 comparative observational studies and 1 randomized controlled trial, totaling 4,186 patients with LVO. The crude odds ratio for post-MT recanalization in patients with LVO who received TNK was comparable to those who received ALT (OR = 1.14; 95% CI 0.57-2.27, I² = 54%). The rate of pre-MT recanalization was significantly higher in those given TNK as a bridging therapy to MT compared to those who received ALT (OR = 2.66; 95% CI 1.60-4.41, I² = 0%; P = <0.001). Functional independence at 90 days was not significantly different between patients with stroke who received TNK and those who were given ALT before MT (OR = 1.41; 95% CI 0.84-2.35; I² = 45%). The 90-day mortality was similar between patients with LVO who received TNK and those who were given ALT prior to undergoing MT (OR = 0.74; 95% CI 0.46-1.21; I² = 0%). CONCLUSIONS: Patients with LVO who received TNK as the primary fibrinolytic agent bridging to MT demonstrated higher rates of pre-MT recanalization, similar rates in post-MT recanalization, and equivalent functional independence outcomes at 90 days compared to those who received ALT. The administration of TNK before MT showed comparable results in the 90-day all-cause mortality rate compared to those who received ALT. These results warrant further trials for TNK to be used as a superior fibrinolytic agent to ALT in LVO-MT candidates.
RESUMEN
BACKGROUND: Early identification of a patient with infection who may develop sepsis is of utmost importance. Unfortunately, this remains elusive because no single clinical measure or test can reflect complex pathophysiological changes in patients with sepsis. However, multiple clinical and laboratory parameters indicate impending sepsis and organ dysfunction. Screening tools using these parameters can help identify the condition, such as SIRS, quick SOFA (qSOFA), National Early Warning Score (NEWS), or Modified Early Warning Score (MEWS). We aim to externally validate qSOFA, SIRS, and NEWS/NEWS2/MEWS for in-hospital mortality among adult patients with suspected infection who presenting to the emergency department. METHODS AND ANALYSIS: PASSEM study is an international prospective external validation cohort study. For 9 months, each participating center will recruit consecutive adult patients who visited the emergency departments with suspected infection and are planned for hospitalization. We will collect patients' demographics, vital signs measured in the triage, initial white blood cell count, and variables required to calculate Charlson Comorbidities Index; and follow patients for 90 days since their inclusion in the study. The primary outcome will be 30-days in-hospital mortality. The secondary outcome will be intensive care unit (ICU) admission, prolonged stay in the ICU (i.e., ≥72 hours), and 30- as well as 90-days all-cause mortality. The study started in December 2021 and planned to enroll 2851 patients to reach 200 in-hospital death. The sample size is adaptive and will be adjusted based on prespecified consecutive interim analyses. DISCUSSION: PASSEM study will be the first international multicenter prospective cohort study that designated to externally validate qSOFA score, SIRS criteria, and EWSs for in-hospital mortality among adult patients with suspected infection presenting to the ED in the Middle East region. STUDY REGISTRATION: The study is registered at ClinicalTrials.gov (NCT05172479).
