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1.
Medicine (Baltimore) ; 103(12): e37403, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518052

RESUMO

RATIONALE: Giant intracranial aneurysms pose a significant threat due to high mortality rates upon rupture, prompting interventions such as neurosurgical clipping or endovascular coiling. PATIENT CONCERNS: We present a rare case involving a 47-year-old female with a history of successfully treated ruptured giant intracranial aneurysms. Six months post-surgical clipping, she developed symptoms of acute ischemic stroke, prompting the decision for neurosurgical coiling and stent-assisted aneurysm coil embolization due to recurrent intracranial aneurysms. DIAGNOSES: Subsequently, occlusion occurred at the previously implanted stent site during embolization, necessitating exploration of alternative therapeutic options. Digital subtraction angiography confirmed stent occlusion in the right middle cerebral artery. INTERVENTIONS: Despite an initial unsuccessful attempt using a direct aspiration first-pass technique, the patient underwent successful mechanical thrombectomy with a retrievable stent, leading to successful reperfusion. This study aims to highlight the challenges and therapeutic strategies in managing delayed cerebral vascular occlusion following stent-assisted coil embolization, emphasizing the significance of exploring alternative interventions to enhance patient outcomes. OUTCOMES: The patient achieved successful reperfusion, and the study underscores the importance of recognizing and addressing delayed cerebral vascular occlusion after stent-assisted coil embolization for recurrent cerebral aneurysms. LESSONS: Our findings suggest that retrievable stent mechanical thrombectomy may serve as a viable therapeutic option in challenging scenarios, emphasizing the need for further exploration of alternative interventions to enhance patient care.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Aneurisma Intracraniano , AVC Isquêmico , Tromboembolia , Feminino , Humanos , Pessoa de Meia-Idade , Aneurisma Roto/cirurgia , Angiografia Cerebral , Embolização Terapêutica/métodos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/cirurgia , AVC Isquêmico/complicações , Estudos Retrospectivos , Stents , Trombectomia , Tromboembolia/complicações , Resultado do Tratamento
2.
JAMA ; 331(10): 840-849, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38329440

RESUMO

Importance: It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy. Objective: To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO. Design, Setting, and Participants: This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023. Interventions: Eligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy. Main Outcomes and Measures: The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours. Results: Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo. Conclusions and Relevance: Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability. Trial Registration: ChiCTR.org.cn Identifier: ChiCTR2100051729.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Feminino , Humanos , Idoso , Método Duplo-Cego , Trombectomia/efeitos adversos , Hemorragias Intracranianas , Metilprednisolona/efeitos adversos
3.
Brain Behav ; 14(1): e3322, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38189637

RESUMO

BACKGROUND: Thyroid hormones have been indicated to be associated with depression, but their relationship with poststroke depression (PSD) remains controversial. Therefore, we performed a meta-analysis to explore the correlation between thyroid hormone levels in acute stroke and PSD. METHODS: We searched databases for eligible studies. Standard mean differences (SMD) and 95% confidence intervals (CI) were applied to evaluate the association among levels of thyroid hormones, including thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4), in acute stroke patients and the risk of PSD. RESULTS: A total of 13 studies were included in the analysis. Compared to non-PSD patients, PSD patients had remarkably lower serum TSH and FT3 levels (TSH: SMD = -0.59, 95%CI = -1.04 to -.15, p = .009; FT3: SMD = -0.40, 95%CI = -.51 to -.30, p = .000) and higher serum FT4 levels (SMD = 0.33, 95%CI = .07-.59, p = .013). Subgroup analysis showed that there may be a more statistically significant association between FT3 and the risk of PSD compared to TSH and FT4. CONCLUSIONS: Our results suggested that patients with lower serum TSH and FT3 levels as well as higher serum FT4 levels in the acute stage of stroke may be more susceptible to PSD.


Assuntos
Depressão , Acidente Vascular Cerebral , Humanos , Depressão/etiologia , Hormônios Tireóideos , Tireotropina , Acidente Vascular Cerebral/complicações , Bases de Dados Factuais
4.
J Stroke Cerebrovasc Dis ; 33(2): 107526, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38096657

RESUMO

BACKGROUND: This study aimed to evaluate the efficacy and safety of adjuvant tirofiban in patients with acute basilar artery occlusion due to large-artery atherosclerotic (LAA) receiving endovascular therapy (EVT). METHODS: This was a non-randomized, multicenter study using data from the Endovascular Treatment for Acute BASILAR Artery Occlusion (BASILAR) registry. Patients with acute basilar artery occlusion due to LAA within 24h of symptom onset who underwent EVT were included. Patients were divided into tirofiban and non-tirofiban groups according to whether tirofiban was used. The primary outcome was the ordinal modified Rankin scale score at 90 days. Safety outcomes were mortality within 90 days and symptomatic intracranial hemorrhage (sICH) within 48 h. RESULTS: A total of 417 patients were included, of whom 275 patients were in the tirofiban group and 142 patients in the non-tirofiban group. Compared with patients in the non-tirofiban group, patients in the tirofiban group were associated with a favorable shift in functional outcome at 90 days (6[4-6] vs 5 [2-6]; adjusted common OR, 2.51; 95 % CI, 1.64-3.83). The mortality was lower in the tirofiban group than the non-tirofiban group (40.7 % vs 58.5 %; adjusted OR, 0.35; 95 % CI, 0.21-0.56). The rate of sICH was 12.2 % in the non-tirofiban group and 5.2 % in the tirofiban group (adjusted OR, 0.37; 95 % CI, 0.17-0.80; P = 0.012). CONCLUSION: Tirofiban plus EVT might improve functional outcomes with a good safety for patients with acute basilar artery occlusion due to LAA. The results need to be confirmed in a randomized trial.


Assuntos
Aterosclerose , Isquemia Encefálica , Procedimentos Endovasculares , Acidente Vascular Cerebral , Humanos , Tirofibana/efeitos adversos , Artéria Basilar/diagnóstico por imagem , Isquemia Encefálica/diagnóstico , Resultado do Tratamento , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Aterosclerose/etiologia , Hemorragias Intracranianas/induzido quimicamente , Trombectomia/efeitos adversos
5.
Ophthalmol Sci ; 4(1): 100357, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37869026

RESUMO

Purpose: The most widely used classifications of age-related macular degeneration (AMD) and its severity stages still rely on color fundus photographs (CFPs). However, AMD has a wide phenotypic variability that remains poorly understood and is better characterized by OCT. We and others have shown that patients with AMD have a distinct plasma metabolomic profile compared with controls. However, all studies to date have been performed solely based on CFP classifications. This study aimed to assess if plasma metabolomic profiles are associated with OCT features commonly seen in AMD. Design: Prospectively designed, cross-sectional study. Participants: Subjects with a diagnosis of AMD and a control group (> 50 years old) from Boston, United States, and Coimbra, Portugal. Methods: All participants were imaged with CFP, used for AMD staging (Age-Related Eye Disease Study 2 classification scheme), and with spectral domain OCT (Spectralis, Heidelberg). OCT images were graded by 2 independent graders for the presence of characteristic AMD features, according to a predefined protocol. Fasting blood samples were collected for metabolomic profiling (using nontargeted high-resolution mass spectrometry by Metabolon Inc). Analyses were conducted using logistic regression models including the worst eye of each patient (AREDS2 classification) and adjusting for confounding factors. Each cohort (United States and Portugal) was analyzed separately and then results were combined by meta-analyses. False discovery rate (FDR) was used to account for multiple comparisons. Main Outcome Measures: Plasma metabolite levels associated with OCT features. Results: We included data on 468 patients, 374 with AMD and 94 controls, and on 725 named endogenous metabolites. Meta-analysis identified significant associations (FDR < 0.05) between plasma metabolites and 3 OCT features: hyperreflective foci (6), atrophy (6), and ellipsoid zone disruption (3). Most associations were seen with amino acids, and all but 1 metabolite presented specific associations with the OCT features assessed. Conclusions: To our knowledge, we show for the first time that plasma metabolites have associations with specific OCT features seen in AMD. Our results support that the wide spectrum of presentations of AMD likely include different pathophysiologic mechanisms by identifying specific pathways associated with each OCT feature. Financial Disclosures: Proprietary or commercial disclosure may be found after the references.

6.
Sensors (Basel) ; 23(21)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37960650

RESUMO

(1) Background: The imaging energy range of a typical Compton camera is limited due to the fact that scattered gamma photons are seldom fully absorbed when the incident energies are above 3 MeV. Further improving the upper energy limit of gamma-ray imaging has important application significance in the active interrogation of special nuclear materials and chemical warfare agents, as well as range verification of proton therapy. (2) Methods: To realize gamma-ray imaging in a wide energy range of 0.3~7 MeV, a principle prototype, named a portable three-layer Compton camera, is developed using the scintillation detector that consists of an silicon photomultiplier array coupled with a Gd3Al2Ga3O12:Ce pixelated scintillator array. Implemented in a list-mode maximum likelihood expectation maximization algorithm, a far-field energy-domain imaging method based on the two interaction events is applied to estimate the initial energy and spatial distribution of gamma-ray sources. The simulation model of the detectors is established based on the Monte Carlo simulation toolkit Geant4. The reconstructed images of a 133Ba, a 137Cs and a 60Co point-like sources have been successfully obtained with our prototype in laboratory tests and compared with simulation studies. (3) Results: The proportion of effective imaging events accounts for about 2%, which allows our prototype to realize the reconstruction of the distribution of a 0.05 µSv/h 137Cs source in 10 s. The angular resolution for resolving two 137Cs point-like sources is 15°. Additional simulated imaging of the 6.13 MeV gamma-rays from 14.1 MeV neutron scattering with water preliminarily demonstrates the imaging capability for high incident energy. (4) Conclusions: We conclude that the prototype has a good imaging performance in a wide energy range (0.3~7 MeV), which shows potential in several MeV gamma-ray imaging applications.

7.
Appl Opt ; 62(20): 5556-5564, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37706874

RESUMO

We used the Monte Carlo simulation method to establish a detector response matrix and the non-negative least-squares method to deconvolute x-ray spectra. The simulation and experimental data verified the effectiveness of this method, and the influence of full-width at the half of the maximum calibration accuracy on the deconvolution results was investigated. The non-negative least-squares method had high accuracy and efficiency compared with others. The results showed that, except for Zn, the relative errors between the inversion and the standard values were less than 0.1% for the simulated spectra. For the experimental data, the relative errors were within 0.2%. The peaks with similar characteristic energies can be better distinguished in the deconvolution spectra, reducing the errors caused by overlapping peaks in subsequent analysis.

8.
Cell Rep Med ; 4(7): 101085, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37348500

RESUMO

Age-related macular degeneration (AMD) is a leading cause of blindness in older adults. Investigating shared genetic components between metabolites and AMD can enhance our understanding of its pathogenesis. We conduct metabolite genome-wide association studies (mGWASs) using multi-ethnic genetic and metabolomic data from up to 28,000 participants. With bidirectional Mendelian randomization analysis involving 16,144 advanced AMD cases and 17,832 controls, we identify 108 putatively causal relationships between plasma metabolites and advanced AMD. These metabolites are enriched in glycerophospholipid metabolism, lysophospholipid, triradylcglycerol, and long chain polyunsaturated fatty acid pathways. Bayesian genetic colocalization analysis and a customized metabolome-wide association approach prioritize putative causal AMD-associated metabolites. We find limited evidence linking urine metabolites to AMD risk. Our study emphasizes the contribution of plasma metabolites, particularly lipid-related pathways and genes, to AMD risk and uncovers numerous putative causal associations between metabolites and AMD risk.


Assuntos
Estudo de Associação Genômica Ampla , Degeneração Macular , Humanos , Idoso , Teorema de Bayes , Degeneração Macular/genética , Degeneração Macular/metabolismo , Metabolômica , Metaboloma/genética
9.
Sensors (Basel) ; 23(11)2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37299810

RESUMO

To overcome the temperature effect of NaI(Tl) detectors for energy spectrometry without additional hardware, a new correction method was put forward based on pulse deconvolution, trapezoidal shaping and amplitude correction, named DTSAC. To verify this method, actual pulses from a NaI(Tl)-PMT detector were measured at various temperatures from -20 °C to 50 °C. Pulse processing and spectrum synthesis showed that the position drift of the 137Cs 662 keV peak was less than 3 keV, and the corresponding resolution at 662 keV of the sum spectra ranged from 6.91% to 10.60% with the trapezoidal width set from 1000 ns to 100 ns. The DTSAC method corrects the temperature effect via pulse processing, and needs no reference peak, reference spectrum or additional circuits. The method solves the problem of correction of pulse shape and pulse amplitude at the same time, and can be used even at a high counting rate.


Assuntos
Iodetos , Tálio , Temperatura , Tálio/química , Sódio
10.
Sensors (Basel) ; 23(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37300023

RESUMO

Silicon-based kinetic energy converters employing variable capacitors, also known as electrostatic vibration energy harvesters, hold promise as power sources for Internet of Things devices. However, for most wireless applications, such as wearable technology or environmental and structural monitoring, the ambient vibration is often at relatively low frequencies (1-100 Hz). Since the power output of electrostatic harvesters is positively correlated to the frequency of capacitance oscillation, typical electrostatic energy harvesters, designed to match the natural frequency of ambient vibrations, do not produce sufficient power output. Moreover, energy conversion is limited to a narrow range of input frequencies. To address these shortcomings, an impacted-based electrostatic energy harvester is explored experimentally. The impact refers to electrode collision and it triggers frequency upconversion, namely a secondary high-frequency free oscillation of the electrodes overlapping with primary device oscillation tuned to input vibration frequency. The main purpose of high-frequency oscillation is to enable additional energy conversion cycles since this will increase the energy output. The devices investigated were fabricated using a commercial microfabrication foundry process and were experimentally studied. These devices exhibit non-uniform cross-section electrodes and a springless mass. The non-uniform width electrodes were used to prevent pull-in following electrode collision. Springless masses from different materials and sizes, such as 0.5 mm diameter Tungsten carbide, 0.8 mm diameter Tungsten carbide, zirconium dioxide, and silicon nitride, were added in an attempt to force collisions over a range of applied frequencies that would not otherwise result in collisions. The results show that the system operates over a relatively wide frequency range (up to 700 Hz frequency range), with the lower limit far below the natural frequency of the device. The addition of the springless mass successfully increased the device bandwidth. For example, at a low peak-to-peak vibration acceleration of 0.5 g (peak-to-peak), the addition of a zirconium dioxide ball doubled the device's bandwidth. Testing with different balls indicates that the different sizes and material properties have different effects on the device's performance, altering its mechanical and electrical damping.


Assuntos
Compostos de Tungstênio , Vibração , Fenômenos Físicos
11.
Stroke ; 54(6): 1569-1577, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37165864

RESUMO

BACKGROUND: The effect of imaging selection paradigms on endovascular thrombectomy outcomes in patients with acute ischemic stroke with large vessel occlusion remains uncertain. The study aimed to assess the effect of basic imaging (noncontrast computed tomography with or without computed tomographic angiography) versus advanced imaging (magnetic resonance imaging or computed tomography perfusion) on clinical outcomes following thrombectomy in patients with stroke with large vessel occlusion in the early and extended windows using a pooled analysis of patient-level data from 2 pivotal randomized clinical trials done in China. METHODS: This post hoc analysis used data from 1182 patients included in 2 multicenter, randomized controlled trials in China that evaluated adjunct therapies to endovascular treatment for acute ischemic stroke (Direct Endovascular Treatment for Large Artery Anterior Circulation Stroke performed from May 20, 2018, through May 2, 2020, and Intravenous Tirofiban Before Endovascular Treatment in Stroke from October 10, 2018, through October 31, 2021). Patients with occlusion of the intracranial internal carotid artery or proximal middle cerebral artery (M1/M2 segments) were categorized according to baseline imaging modality (basic versus advanced) as well as treatment time window (early, 0-6 hours versus extended, 6-24 hours from last known well to puncture). The primary outcome was the proportion of patients with functional independence (modified Rankin Scale score of 0-2) at 90 days. Multivariable Poisson regression analysis was performed to determine the association between imaging selection modality and outcomes after endovascular treatment at each time windows. RESULTS: A total of 1182 patients were included in this cohort analysis, with 648 in the early (471 with basic imaging versus 177 advanced imaging) and 534 in the extended (222 basic imaging versus 312 advanced imaging) time window. There were no differences in 90-day functional independence between the advanced and basic imaging groups in either time windows (early window: adjusted relative risk, 0.99 [95% CI, 0.84-1.16]; P=0.91; extended window: adjusted relative risk, 1.00 [95% CI, 0.84-1.20]; P=0.97). CONCLUSIONS: In this post hoc analysis of 2 randomized clinical trial pooled data involving patients with large vessel occlusion stroke, an association between imaging selection modality and clinical or safety outcomes for patients undergoing thrombectomy in either the early or extended windows was not detected. Our study adds to the growing body of literature on simpler imaging paradigms to assess thrombectomy eligibility across both the early and extended time windows. REGISTRATION: URL: http://www.chictr.org.cn; Unique identifiers: ChiCTR-IOR-17013568 and ChiCTR-INR-17014167.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
N Engl J Med ; 388(14): 1272-1283, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36762852

RESUMO

BACKGROUND: The role of endovascular therapy for acute stroke with a large infarction has not been extensively studied in differing populations. METHODS: We conducted a multicenter, prospective, open-label, randomized trial in China involving patients with acute large-vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower values indicating larger infarction) or an infarct-core volume of 70 to 100 ml. Patients were randomly assigned in a 1:1 ratio within 24 hours from the time they were last known to be well to undergo endovascular therapy and receive medical management or to receive medical management alone. The primary outcome was the score on the modified Rankin scale at 90 days (scores range from 0 to 6, with higher scores indicating greater disability), and the primary objective was to determine whether a shift in the distribution of the scores on the modified Rankin scale at 90 days had occurred between the two groups. Secondary outcomes included scores of 0 to 2 and 0 to 3 on the modified Rankin scale. The primary safety outcome was symptomatic intracranial hemorrhage within 48 hours after randomization. RESULTS: A total of 456 patients were enrolled; 231 were assigned to the endovascular-therapy group and 225 to the medical-management group. Approximately 28% of the patients in both groups received intravenous thrombolysis. The trial was stopped early owing to the efficacy of endovascular therapy after the second interim analysis. At 90 days, a shift in the distribution of scores on the modified Rankin scale toward better outcomes was observed in favor of endovascular therapy over medical management alone (generalized odds ratio, 1.37; 95% confidence interval, 1.11 to 1.69; P = 0.004). Symptomatic intracranial hemorrhage occurred in 14 of 230 patients (6.1%) in the endovascular-therapy group and in 6 of 225 patients (2.7%) in the medical-management group; any intracranial hemorrhage occurred in 113 (49.1%) and 39 (17.3%), respectively. Results for the secondary outcomes generally supported those of the primary analysis. CONCLUSIONS: In a trial conducted in China, patients with large cerebral infarctions had better outcomes with endovascular therapy administered within 24 hours than with medical management alone but had more intracranial hemorrhages. (Funded by Covidien Healthcare International Trading [Shanghai] and others; ANGEL-ASPECT ClinicalTrials.gov number, NCT04551664.).


Assuntos
Isquemia Encefálica , Infarto Cerebral , Procedimentos Endovasculares , AVC Isquêmico , Trombectomia , Humanos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/cirurgia , China , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/etiologia , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia , Estudos Prospectivos , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Resultado do Tratamento
13.
Medicine (Baltimore) ; 101(36): e30514, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36086765

RESUMO

We aimed to evaluate whether Alberta Stroke Program Early CT Score (ASPECTS) applied to hyperdense lesion on noncontrast CT obtained immediately post-thrombectomy (post-ASPECTS) is useful for predicting poor outcome. We retrospectively reviewed patients who underwent noncontrast CT (NCCT) immediately after mechanical thrombectomy between January 2017 and July 2020 in our comprehensive stroke center. We collected baseline NCCT and post-ASPECTS score. The sensitivity, specificity, and positive and negative predictive values of the post-ASPECTS in predicting clinical outcome were calculated. A total of 223 patients were included. The hyperdense lesion on NCCT immediately after endovascular thrombectomy presented in 85.7% (191/223) patients, poor clinical outcome was in 56.1% (112/191) of hyperdense lesion patients. Low post-ASPECTS was associated with poor outcome (OR 0.390; 95% CI 0.258-0.589; P = .001), with an AUCROC curve of 0.753 (95% CI 0.684-0.822), while baseline NCCT-ASPECTS was not (OR 0. 754; 95% CI 0. 497-1.144; P = .185). A score ≤ 7 in post-ASPECTS was the best cut-off to poor clinical outcome (sensitivity 84.8%; specificity 52.7%; positive predictive value 68.4%; negative predictive value 73.8%). Our results point to the proportion of patients who present hyperdense lesion on NCCT is very high, post-ASPECTS could predict poor clinical outcomes in patients with stroke treated with endovascular mechanical thrombectomy, and post-ASPECTS may achieved better predictive value than baseline ASPECTS.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Alberta/epidemiologia , Estudos de Casos e Controles , Angiografia Cerebral/métodos , Humanos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Tomografia Computadorizada por Raios X/métodos
14.
JAMA ; 328(6): 543-553, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35943471

RESUMO

Importance: Tirofiban is a highly selective nonpeptide antagonist of glycoprotein IIb/IIIa receptor, which reversibly inhibits platelet aggregation. It remains uncertain whether intravenous tirofiban is effective to improve functional outcomes for patients with large vessel occlusion ischemic stroke undergoing endovascular thrombectomy. Objective: To assess the efficacy and adverse events of intravenous tirofiban before endovascular thrombectomy for acute ischemic stroke secondary to large vessel occlusion. Design, Setting, and Participants: This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 55 hospitals in China, enrolling 948 patients with stroke and proximal intracranial large vessel occlusion presenting within 24 hours of time last known well. Recruitment took place between October 10, 2018, and October 31, 2021, with final follow-up on January 15, 2022. Interventions: Participants received intravenous tirofiban (n = 463) or placebo (n = 485) prior to endovascular thrombectomy. Main Outcomes and Measures: The primary outcome was disability level at 90 days as measured by overall distribution of the modified Rankin Scale scores from 0 (no symptoms) to 6 (death). The primary safety outcome was the incidence of symptomatic intracranial hemorrhage within 48 hours. Results: Among 948 patients randomized (mean age, 67 years; 391 [41.2%] women), 948 (100%) completed the trial. The median (IQR) 90-day modified Rankin Scale score in the tirofiban group vs placebo group was 3 (1-4) vs 3 (1-4). The adjusted common odds ratio for a lower level of disability with tirofiban vs placebo was 1.08 (95% CI, 0.86-1.36). Incidence of symptomatic intracranial hemorrhage was 9.7% in the tirofiban group vs 6.4% in the placebo group (difference, 3.3% [95% CI, -0.2% to 6.8%]). Conclusions and Relevance: Among patients with large vessel occlusion acute ischemic stroke undergoing endovascular thrombectomy, treatment with intravenous tirofiban, compared with placebo, before endovascular therapy resulted in no significant difference in disability severity at 90 days. The findings do not support use of intravenous tirofiban before endovascular thrombectomy for acute ischemic stroke. Trial Registration: Chinese Clinical Trial Registry Identifier: ChiCTR-IOR-17014167.


Assuntos
Procedimentos Endovasculares , AVC Isquêmico , Inibidores da Agregação Plaquetária , Trombectomia , Tirofibana , Administração Intravenosa , Idoso , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/cirurgia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/cirurgia , Método Duplo-Cego , Procedimentos Endovasculares/métodos , Feminino , Humanos , Hemorragias Intracranianas/induzido quimicamente , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/etiologia , AVC Isquêmico/cirurgia , Masculino , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Tirofibana/administração & dosagem , Tirofibana/efeitos adversos , Tirofibana/uso terapêutico , Resultado do Tratamento
15.
Materials (Basel) ; 15(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35744159

RESUMO

The silver acetylene silver nitrate loading technology of the light initiated high explosive, as one of important means to simulate the structural response of powerful pulsed X-ray, adopts the pulse laser initiation. It has advantages of improvement of practical control, heterogenous loading realization and simultaneous loading timeliness. In this paper, the physical and mathematical models of hot spot initiation and photochemical initiation of energetic materials under the action of laser are firstly established, and then the laser initiation mechanism of the light initiated high explosive is specifically analyzed, and the laser initiation experiment is conducted based on the optical adsorption property of the light initiated high explosive. From this study, the laser initiation thresholds of 193 nm, 266 nm, 532 nm, 1064 nm wavelengths are given, and they are 5.07 mJ/mm2, 6.77 mJ/mm2, 7.21 mJ/mm2 and 10.61 mJ/mm2, respectively, and the complete detonation process is verified by detonation velocity. This work technically supports the study of pulse laser initiation process, mechanism and explosion loading rule as well as the loading technology of the light initiated high explosive to simulate the structural response of X ray.

16.
Clin Interv Aging ; 17: 577-587, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35497054

RESUMO

Objective: This study examined the functional outcomes and safety of endovascular treatment (EVT) in acute ischemic stroke (AIS) patients owing to large vessel occlusion of the anterior circulation, presented during a late-time window (6-24 hours after last seen well (LSW)) in a real-world practice. Methods: This was a retrospective analysis from a bi-center prospective cohort. According to the stroke treatment, patients with continuous Alberta Stroke Plan Early Aspect score (ASPECTS) ≥6 on non-contrast CT (NCCT) and moderate to good collateral state on CT angiography (CTA) were divided into EVT group and standard medical treatment (SMT) group. The primary outcome was the rate of functional independence (90-day mRS ≤2). Safety outcomes were the occurrence of symptomatic intracranial hemorrhage (sICH) and the 90-day mortality. Results: Among the 288 enrolled patients (53.5% male, median age 64 years), there were 167 patients in the EVT group and 121 in the SMT group. After multivariable adjustments for potential confounders, EVT was associated with functional independence (adjusted OR: 3.052; 95% confidence interval (CI): 1.553-5.997; p = 0.001). In the PSM cohort, 44.2% (42/95) of patients in the EVT group versus 18.9% (18/95) in the SMT group achieved functional independence (OR: 3.39, 95% CI: 1.763-6.517), and there was a significant difference favoring EVT over the SMT in the overall distribution of mRS (OR: 2.170, 95% CI: 1.302-3.618) at 90 days. The rate of sICH did not differ between the EVT and SMT groups (10.5% vs 8.4%, p = 0.804) nor did 90-day mortality (18.9% vs 22.1%, p = 0.719). No interaction was found in p-values with statistical significance in subgroup analysis. Conclusion: This real-world experience suggests that EVT for late-presenting stroke patients, based on small core on NCCT and moderate to good collaterals on CTA, is associated with better outcomes than SMT alone, with no increase in sICH and 90-day mortality rates.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Feminino , Humanos , Hemorragias Intracranianas , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Masculino , Perfusão , Estudos Prospectivos , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Tomografia Computadorizada por Raios X
17.
Appl Radiat Isot ; 186: 110212, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35569263

RESUMO

This research aims at comparing the performance of different machine learning algorithms used for NaI(TI) gamma-ray detector based radioisotope identification. Six machine learning algorithms were implemented, including support vector machine (SVM), k-nearest neighbor (KNN), logistic regression (LR), naive Bayes (NB), decision tree (DT), and multilayer perceptron (MLP). The hyper-parameters of each model were elaborately optimized. The effects of data size, statistical fluctuation, and spectrum drift were considered. Results show that for smaller data size (5 types of radioisotopes and 6000 spectra), the support vector machine and the logistic regression classifier exhibit higher identification accuracy with less training/predicting time. Whereas for larger data size (14 types of radioisotopes corresponding to the standard IEC 62327-2017), the multilayer perceptron showed highest accuracy but required the longest time for model training. The naive Bayes classifier and the decision tree were prone to make mistakes when fluctuations and distortions were added to the spectra. The k-nearest neighbor classifier, though showing high accuracy for most data sets, consumed the longest time while making prediction.


Assuntos
Aprendizado de Máquina , Máquina de Vetores de Suporte , Algoritmos , Teorema de Bayes , Redes Neurais de Computação , Radioisótopos
18.
J Autism Dev Disord ; 52(6): 2497-2504, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34184142

RESUMO

Autism spectrum disorder (ASD) is a neurodevelopmental disorder. The associations between the cerebellum and clinical traits remain unclear. We performed amplitude of low-frequency fluctuation (ALFF) analysis to explore the associations between spontaneous brain activity and clinical traits. 361 juvenile ASD patients were included from the ABIDEII database. In the ASD group, the mean ALFF values of cerebellum 4 5 were correlated with SRS awareness and communication. The mean ALFF values of cerebellum 6 and vermis 4 5 were both positively correlated with SRS total, awareness, communication, and motivation. In contrast, the mean ALFF values of vermis 1 2 were negatively correlated with SRS total, awareness, and mannerisms. Our study suggests a role of the cerebellum in functional impairments in ASD.


Assuntos
Transtorno do Espectro Autista , Encéfalo , Mapeamento Encefálico , Estudos de Casos e Controles , Cerebelo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Fenótipo
19.
Front Neurol ; 12: 736309, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34899561

RESUMO

Cerebral small vessel disease (cSVD)-a common cause of stroke and vascular dementia-is a group of clinical syndromes that affects the brain's small vessels, including arterioles, capillaries, and venules. Its pathogenesis is not fully understood, and effective treatments are limited. Increasing evidence indicates that an elevated total serum homocysteine level is directly and indirectly associated with cSVD, and endothelial dysfunction plays an active role in this association. Hyperhomocysteinemia affects endothelial function through oxidative stress, inflammatory pathways, and epigenetic alterations at an early stage, even before the onset of small vessel injuries and the disease. Therefore, hyperhomocysteinemia is potentially an important therapeutic target for cSVD. However, decreasing the homocysteine level is not sufficiently effective, possibly due to delayed treatment, which underlying reason remains unclear. In this review, we examined endothelial dysfunction to understand the close relationship between hyperhomocysteinemia and cSVD and identify the optimal timing for the therapy.

20.
PLoS One ; 16(10): e0259283, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34714878

RESUMO

This exploration primarily aims to jointly apply the local FCN (fully convolution neural network) and YOLO-v5 (You Only Look Once-v5) to the detection of small targets in remote sensing images. Firstly, the application effects of R-CNN (Region-Convolutional Neural Network), FRCN (Fast Region-Convolutional Neural Network), and R-FCN (Region-Based-Fully Convolutional Network) in image feature extraction are analyzed after introducing the relevant region proposal network. Secondly, YOLO-v5 algorithm is established on the basis of YOLO algorithm. Besides, the multi-scale anchor mechanism of Faster R-CNN is utilized to improve the detection ability of YOLO-v5 algorithm for small targets in the image in the process of image detection, and realize the high adaptability of YOLO-v5 algorithm to different sizes of images. Finally, the proposed detection method YOLO-v5 algorithm + R-FCN is compared with other algorithms in NWPU VHR-10 data set and Vaihingen data set. The experimental results show that the YOLO-v5 + R-FCN detection method has the optimal detection ability among many algorithms, especially for small targets in remote sensing images such as tennis courts, vehicles, and storage tanks. Moreover, the YOLO-v5 + R-FCN detection method can achieve high recall rates for different types of small targets. Furthermore, due to the deeper network architecture, the YOL v5 + R-FCN detection method has a stronger ability to extract the characteristics of image targets in the detection of remote sensing images. Meanwhile, it can achieve more accurate feature recognition and detection performance for the densely arranged target images in remote sensing images. This research can provide reference for the application of remote sensing technology in China, and promote the application of satellites for target detection tasks in related fields.


Assuntos
Redes Neurais de Computação , Reconhecimento Automatizado de Padrão/métodos , Imagens de Satélites/métodos , Reconhecimento Automatizado de Padrão/normas , Imagens de Satélites/normas
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