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1.
Int J Surg ; 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39365831

RESUMEN

BACKGROUND: Recent clinical trials have shown that patients with large ischemic cores have better outcomes with endovascular thrombectomy (EVT) compared with standard medical treatment (SMT) alone.We aim to assess whether the relationship between EVT and improvements in clinical outcomes varies depending on the location of the occlusive sites. METHODS: This study is a subgroup analysis conducted within a prospective, nationwide, multi-center registry. The cohort included patients with acute large vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 0 to 5 within 24 hours from last known well. We utilized the adjusted common odds ratio for a shift toward better outcome on the modified Rankin Scale after EVT compared with SMT alone as the primary outcome. Safety outcomes included symptomatic intracranial hemorrhage (sICH). RESULTS: A total of 745 patients with large ischemic cores were included: 272(36.5%) with internal carotid artery occlusion, 392(52.6%) with M1 segment of the middle cerebral artery occlusion, and 81(11.0%) with M2 segment of the middle cerebral artery occlusion. The adjusted common odds ratios were as follows: 1.98 (95% CI, 1.01-3.89) for ICA occlusions, 2.09 (95% CI, 1.35-3.23) for M1 occlusions, and 1.13 (95% CI, 0.43-2.94) for M2 occlusions. There was no significant treatment-by-occlusion site interaction observed (P=0.69). However, the incidence of sICH was significantly greater in all groups receiving EVT than in those receiving SMT alone. Additionally, we observed that the secondary outcomes and subgroup analyses were generally consistent with the main outcomes. CONCLUSIONS: In this study, we found that patients with internal carotid artery and M1 occlusion demonstrated a better outcome with EVT, while the benefit for patients with M2 occlusion remains uncertain.

2.
Eur Stroke J ; : 23969873241286983, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39345180

RESUMEN

RATIONALE: Adjunct intra-arterial alteplase has been shown to potentially improve clinical outcomes in patients with large vessel occlusion (LVO) stroke who have undergone successful endovascular thrombectomy. Tenecteplase, known for its enhanced fibrin specificity and extended activity duration, could potentially enhance outcomes in stroke patients after successful reperfusion when used as an adjunct intra-arterial therapy. AIM: To explore the safety and efficacy of intra-arterial tenecteplase after successful endovascular thrombectomy in patients with LVO stroke. SAMPLE SIZE: To randomize 498 participants 1:1 to receive intra-arterial tenecteplase or no intra-arterial adjunctive thrombolysis therapy. METHODS AND DESIGN: An investigator-initiated, prospective, randomized, open-label, blind-endpoint multicenter clinical trial. Eligible patients with anterior circulation LVO stroke presenting within 24 h from symptom onset (time last known well) and excellent to complete reperfusion (expanded Thrombolysis In Cerebral Infarction (eTICI) scale 2c-3) at endovascular thrombectomy are planned to be randomized. OUTCOMES: The primary outcome is freedom from disability (modified Rankin Scale, mRS, of 0-1) at 90 days. The primary safety outcomes are mortality through 90 days and symptomatic intracranial hemorrhage within 48 h. DISCUSSION: The POST-TNK trial will evaluate the efficacy and safety of intra-arterial tenecteplase in patients with LVO stroke and excellent to complete reperfusion.

3.
J Neurointerv Surg ; 2024 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-39299744

RESUMEN

BACKGROUND: Clinical evidence of the potential influence of stress hyperglycemia ratio (SHR) for patients with large ischemic stroke whether or not receiving endovascular therapy is not clear. METHODS: This study was a subanalysis of a prospective, multicenter registry, and included 745 patients with large ischemic stroke across 38 centers in China. A total of 427 patients were included in this study, with 285 received endovascular therapy (EVT) and 142 received standard medical therapy (SMT). SHR was defined as glucose (mmol/L)/(1.59 × HbA1C)-2.59. The primary outcome was a moderate neurological outcome (modified Rankin Scale (mRS) score ≤3) at 90 days. RESULTS: A significant interaction was observed between SHR and whether received EVT (p=0.017). Among patients who received EVT (adjusted OR (aOR) 0.46; 95% CI 0.23 to 0.92; p=0.029), patients in the highest tertile of SHR were significantly less likely to achieve a moderate neurological outcome at 90 days compared with those in the lowest tertile. However, this association was not observed in patients receiving SMT (aOR 2.46; 95% CI 0.74 to 8.21; p=0.142). EVT patients with higher SHR had a significantly higher incidence of symptomatic intracranial hemorrhage compared with lower SHR (aOR 3.29; 95% CI 1.08 to 10.06; p=0.036), while such an association was not observed in the SMT group (aOR 1.52; 95% CI 0.56 to 4.12; p=0.410). CONCLUSIONS: In patients with large ischemic stroke treated with EVT, SHR is associated with a reduced likelihood of achieving a moderate neurological outcome, as well as an increased risk of symptomatic intracranial hemorrhage. TRIAL REGISTRATION NUMBER: ChiCTR2100051664.

4.
Entropy (Basel) ; 26(7)2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-39056898

RESUMEN

We study genuine multipartite entanglement (GME) and multipartite k-entanglement based on q-concurrence. Well-defined parameterized GME measures and measures of multipartite k-entanglement are presented for arbitrary dimensional n-partite quantum systems. Our GME measures show that the GHZ state is more entangled than the W state. Moreover, our measures are shown to be inequivalent to the existing measures according to entanglement ordering. Detailed examples show that our measures characterize the multipartite entanglement finer than some existing measures, in the sense that our measures identify the difference of two different states while the latter fail.

6.
Front Neurol ; 15: 1367177, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38751885

RESUMEN

Introduction: Symptomatic intracranial hemorrhage (sICH) is a serious complication of acute ischemic stroke (AIS) after endovascular treatment (EVT). Limited data exist regarding predictors and clinical implications of sICH after EVT, underscoring the significance of identifying risk factors to enhance prevention strategies. Therefore, the main objective of this study was to evaluate the incidence of sICH and identify its predictors after EVT in patients with large infarct core-AIS in the pre-circulation stage. Methods: Using data from the EVT for the Pre-circulation Large Infarct Core-AIS Study, we enrolled patients who were treated with EVT from the Prospective Multicenter Cohort Study of Early Treatment in Acute Stroke (MAGIC) registry. Baseline demographics, medical history, vascular risk factors, blood pressure, stroke severity, radiographic features, and EVT details were collected. The patients were classified into three groups: without intracranial hemorrhage (ICH), with asymptomatic intracranial hemorrhage (aICH), and sICH, based upon the occurrence of sICH. The main outcomes were the occurrence of sICH according to the Heidelberg Bleeding Classification and functional condition at 90 days. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curves were used to identify independent predictors of sICH after EVT. Results: The study recruited a total of 490 patients, of whom 13.3% (n = 65) developed sICH. Patients with sICH had less favorable outcomes than those without intracranial hemorrhage (ICH) and those with aICH (13.8% vs. 43.5% vs. 32.2%, respectively; p < 0.001). The overall mortality was 41.8% (n = 205) at 90 days post-EVT. The univariate analysis revealed significant differences among the three groups in terms of blood glucose levels at admission, probability of favorable outcomes, incidence of brain herniation, and 90-day mortality. The multifactorial logistic regression analysis revealed that the blood glucose level at admission [odds ratio (OR) 1.169, p < 0.001, confidence interval (CI) 1.076-1.269] was an independent predictor of sICH. A blood glucose level of 6.95 mmol/L at admission was the best predictor of sICH, with an area under the ROC curve (AUC) of 0.685 (95% CI: 0.616-0.754). Discussion: The study findings demonstrated that the probability of sICH after EVT was 13.3% in patients with pre-circulation large infarct core-AIS, and sICH increased the risk of an unfavorable prognosis. Higher blood glucose levels at admission were associated with sICH after EVT in patients with pre-circulation large infarct core AIS. These findings underscore the importance of early management strategies to mitigate this risk.

7.
Entropy (Basel) ; 26(2)2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38392382

RESUMEN

The monogamy property of entanglement is an intriguing feature of multipartite quantum entanglement. Most entanglement measures satisfying the monogamy inequality have turned out to be convex. Whether nonconvex entanglement measures obey the monogamy inequalities remains less known at present. As a well-known measure of entanglement, the logarithmic negativity is not convex. We elucidate the constraints of multi-qubit entanglement based on the logarithmic convex-roof extended negativity (LCREN) and the logarithmic convex-roof extended negativity of assistance (LCRENoA). Using the Hamming weight derived from the binary vector associated with the distribution of subsystems, we establish monogamy inequalities for multi-qubit entanglement in terms of the αth-power (α≥4ln2) of LCREN, and polygamy inequalities utilizing the αth-power (0≤α≤2) of LCRENoA. We demonstrate that these inequalities give rise to tighter constraints than the existing ones. Furthermore, our monogamy inequalities are shown to remain valid for the high-dimensional states that violate the CKW monogamy inequality. Detailed examples are presented to illustrate the effectiveness of our results in characterizing the multipartite entanglement distributions.

8.
Phys Rev E ; 107(5-1): 054134, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37329009

RESUMEN

We study multipartite entanglement and genuine tripartite entanglement based on general symmetric informationally complete positive operator valued measurements (GSIC-POVMs). By representing the bipartite density matrices in terms of GSIC-POVMs, we obtain the lower bound of the sum of squares of the corresponding probability. We then construct a special matrix with the correlation probability of GSIC-POVMs to derive useful and operational criteria to detect genuine tripartite entanglement. We also generalize the results to obtain a sufficient criterion to detect entanglement for multipartite quantum states in arbitrary dimensions. Detailed examples show that the new method can detect more entangled and genuine entangled states than previous criteria.

9.
iScience ; 26(4): 106306, 2023 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-36994076

RESUMEN

Universal quantum algorithms (UQA) implemented on fault-tolerant quantum computers are expected to achieve an exponential speedup over classical counterparts. However, the deep quantum circuits make the UQA implausible in the current era. With only the noisy intermediate-scale quantum (NISQ) devices in hand, we introduce the quantum-assisted quantum algorithm, which reduces the circuit depth of UQA via NISQ technology. Based on this framework, we present two quantum-assisted quantum algorithms for simulating open quantum systems, which utilize two parameterized quantum circuits to achieve a short-time evolution. We propose a variational quantum state preparation method, as a subroutine to prepare the ancillary state, for loading a classical vector into a quantum state with a shallow quantum circuit and logarithmic number of qubits. We demonstrate numerically our approaches for a two-level system with an amplitude damping channel and an open version of the dissipative transverse field Ising model on two sites.

10.
Sensors (Basel) ; 22(14)2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35891104

RESUMEN

Display crosstalk defect detection is an important link in the display quality inspection process. We propose a crosstalk defect detection method based on salient color channel frequency domain filtering. Firstly, the salient color channel in RGBY is selected by the maximum relative entropy criterion, and the color quaternion matrix of the displayed image is formed with the Lab color space. Secondly, the image color quaternion matrix is converted into the logarithmic spectrum in the frequency domain through the hyper-complex Fourier transform. Finally, Gaussian threshold band-pass filtering and hyper-complex inverse Fourier transform are used to separate the low-contrast defects and background of the display image. The experimental results show that the accuracy of the proposed algorithm reaches 96% for a variety of crosstalk defect detection. Compared with the current advanced defect detection algorithms, the effectiveness of the proposed method for low-contrast crosstalk defect detection is confirmed.

11.
Sci Rep ; 11(1): 9640, 2021 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-33953299

RESUMEN

We study the detection of multipartite entanglement based on the generalized local uncertainty relations. A sufficient criterion for the entanglement of four-partite quantum systems is presented in terms of the local uncertainty relations. Detailed examples are given to illustrate the advantages of our criterion. The approach is generalized to general multipartite entanglement cases.

12.
Entropy (Basel) ; 24(1)2021 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-35052044

RESUMEN

We investigate the discrimination of pure-mixed (quantum filtering) and mixed-mixed states and compare their optimal success probability with the one for discriminating other pairs of pure states superposed by the vectors included in the mixed states. We prove that under the equal-fidelity condition, the pure-pure state discrimination scheme is superior to the pure-mixed (mixed-mixed) one. With respect to quantum filtering, the coherence exists only in one pure state and is detrimental to the state discrimination for lower dimensional systems; while it is the opposite for the mixed-mixed case with symmetrically distributed coherence. Making an extension to infinite-dimensional systems, we find that the coherence which is detrimental to state discrimination may become helpful and vice versa.

13.
Entropy (Basel) ; 22(2)2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-33285936

RESUMEN

The quantum measurement incompatibility is a distinctive feature of quantum mechanics. We investigate the incompatibility of a set of general measurements and classify the incompatibility by the hierarchy of compatibilities of its subsets. By using the approach of adding noises to measurement operators, we present a complete classification of the incompatibility of a given measurement assemblage with n members. Detailed examples are given for the incompatibility of unbiased qubit measurements based on a semidefinite program.

14.
Sci Rep ; 7(1): 4869, 2017 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-28687739

RESUMEN

We study the local unitary equivalence for two and three-qubit mixed states by investigating the invariants under local unitary transformations. For two-qubit system, we prove that the determination of the local unitary equivalence of 2-qubits states only needs 14 or less invariants for arbitrary two-qubit states. Using the same method, we construct invariants for three-qubit mixed states. We prove that these invariants are sufficient to guarantee the LU equivalence of certain kind of three-qubit states. Also, we make a comparison with earlier works.

15.
Sci Rep ; 6: 35735, 2016 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-27775010

RESUMEN

We study universal uncertainty relations and present a method called joint probability distribution diagram to improve the majorization bounds constructed independently in [Phys. Rev. Lett. 111, 230401 (2013)] and [J. Phys. A. 46, 272002 (2013)]. The results give rise to state independent uncertainty relations satisfied by any nonnegative Schur-concave functions. On the other hand, a remarkable recent result of entropic uncertainty relation is the direct-sum majorization relation. In this paper, we illustrate our bounds by showing how they provide a complement to that in [Phys. Rev. A. 89, 052115 (2014)].

16.
Sci Rep ; 5: 10727, 2015 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-26090962

RESUMEN

The Holevo bound is a keystone in many applications of quantum information theory. We propose " maximal Holevo quantity for weak measurements" as the generalization of the maximal Holevo quantity which is defined by the optimal projective measurements. The scenarios that weak measurements is necessary are that only the weak measurements can be performed because for example the system is macroscopic or that one intentionally tries to do so such that the disturbance on the measured system can be controlled for example in quantum key distribution protocols. We evaluate systematically the maximal Holevo quantity for weak measurements for Bell-diagonal states and find a series of results. Furthermore, we find that weak measurements can be realized by noise and project measurements.

17.
Biochemistry ; 43(12): 3499-506, 2004 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-15035620

RESUMEN

The secretion of lung surfactant in alveolar type II cells is a complex process involving the fusion of lamellar bodies with the plasma membrane. This process is somewhat different from the exocytosis of hormones and neurotransmitters. For example, it is a relatively slower process, and lamellar bodies are very large vesicles with a diameter of approximately 1 microm. SNARE proteins are the conserved molecular machinery of exocytosis in the majority of secretory cells. However, their involvement in surfactant secretion has not been reported. Here, we showed that syntaxin 2 and SNAP-23 are expressed in alveolar type II cells. Both proteins are associated with the plasma membrane, and to some degree with lamellar bodies. An antisense oligonucleotide complementary to syntaxin 2 decreased its mRNA and protein levels. The same oligonucleotide also inhibited surfactant secretion, independent of secretagogues. A peptide derived from the N-terminus of syntaxin 2 or the C-terminus of SNAP-23 significantly inhibited Ca(2+)- and GTPgammaS-stimulated surfactant secretion from permeabilized type II cells in a dose-dependent manner. Furthermore, introduction of anti-syntaxin 2 or anti-SNAP-23 antibodies into permeabilized type II cells also inhibited surfactant release. Our results suggest that syntaxin 2 and SNAP-23 are required for regulated surfactant secretion.


Asunto(s)
Antígenos de Superficie/fisiología , Proteínas Portadoras/fisiología , Proteínas del Tejido Nervioso/fisiología , Alveolos Pulmonares/metabolismo , Surfactantes Pulmonares/metabolismo , Proteínas de Transporte Vesicular , Secuencia de Aminoácidos , Animales , Antígenos de Superficie/genética , Antígenos de Superficie/inmunología , Proteínas Portadoras/inmunología , Permeabilidad de la Membrana Celular/inmunología , Permeabilidad de la Membrana Celular/fisiología , Células Cultivadas , Sueros Inmunes/farmacología , Masculino , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/inmunología , Oligonucleótidos Antisentido/farmacología , Fragmentos de Péptidos/farmacología , Alveolos Pulmonares/citología , Surfactantes Pulmonares/antagonistas & inhibidores , Proteínas Qb-SNARE , Proteínas Qc-SNARE , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Proteínas SNARE , Fracciones Subcelulares/metabolismo , Sintaxina 1
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