Enhancing the First-Pass Effect in Acute Stroke: The Impact of Stent Retriever Characteristics.

Introduction: Although stentrievers (SRs) have been a mainstay of mechanical thrombectomy (MT), and current guidelines recommend the use of SRs in the treatment of large vessel occlusion stroke (LVO), there is a paucity of studies in the literature comparing SRs directly against each other in terms of mechanical and functional properties. Timely access to endovascular therapy and the ability to restore intracranial flow in a safe, efficient, and efficacious manner have been critical to the success of MT. This study aimed to investigate the impact of contemporary SR characteristics, including model, brand, size, and length, on the first-pass effect (FPE) in patients with acute ischemic stroke. Methods: Consecutive patients with M1 occlusion treated with a single SR+BGC were recruited from the ROSSETTI registry. The primary outcome was the FPE that was defined as modified (mFPE) or true (tFPE) for the achievement of modified thrombolysis in cerebral infarction (mTICI) grades 2b-3 or 3 after a single device pass, respectively. We compared patients who achieved mFPE with those who achieved tFPE according to SR characteristics. Results: We included 610 patients (52.3% female and 47.7% male, mean age 75.1 ± 13.62 years). mFPE was achieved in 357 patients (58.5%), whereas tFPE was achieved in 264 (43.3%). There was no significant association between SR characteristics and mFPE or tFPE. Specifically, the SR size did not show a statistically significant relationship with improvement in FPE. Similarly, the length of the SR did not yield significant differences in the mFPE and tFPE, even when the data were grouped. Conclusions: Our data indicate that contemporary SR-mediated thrombectomy characteristics, including model, brand, size, and length, do not significantly affect the FPE.

Diagnostic accuracy of regadenoson stress echocardiography: concordance with gated-spect myocardial perfusion imaging.

Regadenoson Stress Echocardiography (RSE) can detect myocardial ischemia, and its diagnostic accuracy should be evaluated. We sought to investigate the agreement between RSE and gated-SPECT myocardial perfusion imaging (MPI) and appraise its diagnostic accuracy. Consecutive patients (n = 202) referred for non-invasive evaluation of myocardial ischemia, with (38.6%) or without a previous coronary artery disease (CAD) diagnosis, were enrolled. Both tests were performed simultaneously. Invasive coronary angiography (CA) is considered the gold standard. The mean age was 70.9 (9.8) years, and 59.9% were male. The prevalence of cardiovascular risk factors (arterial hypertension [81.7%], diabetes mellitus [37.6%], hypercholesterolemia [71.8%], and smoking [18.8%]) was high. Forty-four patients (21.8%) had a non-interpretable electrocardiogram, 15 (34.1%) of them were a result of ventricular paced-rhythm, while 29 (65.9%) were a result of advanced left ventricular branch block. The overall agreement between both diagnostic techniques was good: Gwet's AC1 0.66 (CI95% 0.55 to 0.76), and it was higher in patients without a previous CAD diagnosis: 0.76 (CI95% 0.65 to 0.87). In the biased sample (those who underwent CA), RSE and nuclear study sensitivity was 0.50 and 0.78 and specificity was 0.75 and 0.75, respectively. We noted a dramatic reduction in sensitivity for RSE after debiasing (debiased sensitivity of 0.16), and the negative predictive value was similar to the biased and debiased samples. RSE is in strong agreement with gated-SPECT MPI. However, its low sensitivity and negative predictive value preclude its use as a bedside test to detect myocardial ischemia.

Bienzyme amperometric biosensor using gold nanoparticle-modified electrodes for the determination of inulin in foods.

A biosensor design involving coimmobilization of fructose dehydrogenase (FDH) and inulinase (INU) on a gold nanoparticle-cysteamine (Cyst) self-assembled monolayer (SAM)-modified gold electrode (Au(coll)-Cyst-AuE), for the determination of the carbohydrate inulin in foodstuffs, is reported. Tetrathiafulvalene (TTF), used as the mediator, was also coimmobilized by crosslinking with glutaraldehyde. INU catalyzes the hydrolysis of inulin, forming fructose that is detected through the fructose dehydrogenase system by the electrochemical oxidation of TTF at the bioelectrode. The variables involved in the preparation and performance of both the single enzyme FDH biosensor and the bienzyme inulin biosensor were optimized. The FDH-Au(coll)-Cyst-AuE biosensor exhibited rapid and sensitive response to fructose, allowing the obtention of improved analytical characteristics for the determination of fructose with respect to other FDH electrochemical biosensors. Moreover, the lifetime of this biosensor was 35 days. The bienzyme INU/FDH-Au(coll)-Cyst-AuE biosensor provided a calibration plot for inulin in the (5-100)x10(-6) M linear range, with a detection limit of 6.6 x 10(-7) mol L(-1). One single bienzyme biosensor responded within the control limits, set at +/-3x the standard deviation of the currents measured on the first day of use, for more than 5 months. Furthermore, the biosensor exhibited high selectivity with respect to other carbohydrates. The usefulness of the biosensor was evaluated by the rapid determination of inulin in food products involving minimization of the fructose interference.