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1.
J Neurochem ; 168(6): 1030-1044, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38344886

RESUMEN

In this study, we investigated the potential involvement of TNFSF9 in reperfusion injury associated with ferroptosis in acute ischaemic stroke patients, mouse models and BV2 microglia. We first examined TNFSF9 changes in peripheral blood from stroke patients with successful reperfusion, and constructed oxygen-glucose deprivation-reperfusion (OGD-R) on BV2 microglia, oxygen-glucose deprivation for 6 h followed by reoxygenation and re-glucose for 24 h, and appropriate over-expression or knockdown of TNFSF9 manipulation on BV2 cells and found that in the case of BV2 cells encountering OGD-R over-expression of TNFSF9 resulted in increased BV2 apoptosis. Still, the knockdown of TNFSF9 ameliorated apoptosis and ferroptosis. In an in vivo experiment, we constructed TNFSF9 over-expression or knockout mice by intracerebral injection of TNFSF9-OE or sh-TNFSF9 adenovirus. We performed the middle cerebral artery occlusion (MCAO) model on day four, 24 h after ligation of the proximal artery, for half an hour to recanalize. As luck would have it, over-expression of TNFSF9 resulted in increased brain infarct volumes, neurological function scores and abnormalities in TNFSF9-related TRAF1 and ferroptosis-related pathways, but knockdown of TNFSF9 improved brain infarcts in mice as well as reversing TNFSF9-related signalling pathways. In conclusion, our data provide the first evidence that TNFSF9 triggers microglia activation by activating the ferroptosis signalling pathway following ischaemic stroke, leading to brain injury and neurological deficits.


Asunto(s)
Ferroptosis , Accidente Cerebrovascular Isquémico , Ratones Endogámicos C57BL , Ratones Noqueados , Daño por Reperfusión , Anciano , Animales , Femenino , Humanos , Masculino , Ratones , Persona de Mediana Edad , Progresión de la Enfermedad , Ferroptosis/fisiología , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/patología , Microglía/metabolismo , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología
2.
Lancet ; 402(10406): 965-974, 2023 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-37640037

RESUMEN

BACKGROUND: Intravenous thrombolysis is recommended before endovascular treatment, but its value has been questioned in patients who are admitted directly to centres capable of endovascular treatment. Existing randomised controlled trials have indicated non-inferiority of endovascular treatment alone or have been statistically inconclusive. We formed the Improving Reperfusion Strategies in Acute Ischaemic Stroke collaboration to assess non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment. METHODS: We conducted a systematic review and individual participant data meta-analysis to establish non-inferiority of endovascular treatment alone versus intravenous thrombolysis plus endovascular treatment. We searched PubMed and MEDLINE with the terms "stroke", "endovascular treatment", "intravenous thrombolysis", and synonyms for articles published from database inception to March 9, 2023. We included randomised controlled trials on the topic of interest, without language restrictions. Authors of the identified trials agreed to take part, and individual participant data were provided by the principal investigators of the respective trials and collated centrally by the collaborators. Our primary outcome was the 90-day modified Rankin Scale (mRS) score. Non-inferiority of endovascular treatment alone was assessed using a lower boundary of 0·82 for the 95% CI around the adjusted common odds ratio (acOR) for shift towards improved outcome (analogous to 5% absolute difference in functional independence) with ordinal regression. We used mixed-effects models for all analyses. This study is registered with PROSPERO, CRD42023411986. FINDINGS: We identified 1081 studies, and six studies (n=2313; 1153 participants randomly assigned to receive endovascular treatment alone and 1160 randomly assigned to receive intravenous thrombolysis and endovascular treatment) were eligible for analysis. The risk of bias of the included studies was low to moderate. Variability between studies was small, and mainly related to the choice and dose of the thrombolytic drug and country of execution. The median mRS score at 90 days was 3 (IQR 1-5) for participants who received endovascular treatment alone and 2 (1-4) for participants who received intravenous thrombolysis plus endovascular treatment (acOR 0·89, 95% CI 0·76-1·04). Any intracranial haemorrhage (0·82, 0·68-0·99) occurred less frequently with endovascular treatment alone than with intravenous thrombolysis plus endovascular treatment. Symptomatic intracranial haemorrhage and mortality rates did not differ significantly. INTERPRETATION: We did not establish non-inferiority of endovascular treatment alone compared with intravenous thrombolysis plus endovascular treatment in patients presenting directly at endovascular treatment centres. Further research could focus on cost-effectiveness analysis and on individualised decisions when patient characteristics, medication shortages, or delays are expected to offset a potential benefit of administering intravenous thrombolysis before endovascular treatment. FUNDING: Stryker and Amsterdam University Medical Centers, University of Amsterdam.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular/tratamiento farmacológico , Hemorragias Intracraneales , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía , Terapia Trombolítica , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
Small ; : e2401770, 2024 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-38764303

RESUMEN

Ultrathin PtSe2 ribbons can host spin-polarized edge states and distinct edge electrocatalytic activity, emerging as a promising candidate for versatile applications in various fields. However, the direct synthesis is still challenging and the growth mechanism is still unclear. Herein, the arrayed growth of ultrathin PtSe2 ribbons on bunched vicinal Au(001) facets, via a facile chemical vapor deposition (CVD) route is reported. The ultrathin PtSe2 flakes can transform from traditional irregular shapes to desired ribbon shapes by increasing the height of bunched and unidirectionally oriented Au steps (with step height hstep) is found. This crossover, occurring at hstep ≈ 3.0 nm, defines the tailored growth from step-flow to single-terrace-confined modes, as validated by density functional theory calculations of the different system energies. On the millimeter-scale single-crystal Au(001) films with aligned steps, the arrayed ultrathin PtSe2 ribbons with tunable width of ≈20-1000 nm, which are then served as prototype electrocatalysts for hydrogen evolution reaction (HER) is achieved. This work should represent a huge leap in the direct synthesis and the mechanism exploration of arrayed ultrathin transition-metal dichalcogenides (TMDCs) ribbons, which should stimulate further explorations of the edge-related physical properties and practical applications.

4.
Opt Lett ; 49(3): 542-545, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300054

RESUMEN

We developed a resolved Raman sideband cooling scheme that can efficiently prepare a single optically trapped cesium (Cs) atom in its motional ground states. A two-photon Raman process between two outermost Zeeman sublevels in a single hyperfine state is applied to reduce the phonon number. Our scheme is less sensitive to the variation in the magnetic field than the commonly used scheme where the two outermost Zeeman sublevels belonging to the two separate ground hyperfine states are taken. Fast optical pumping with less spontaneous emission guarantees the efficiency of the cooling process. After cooling for 50 ms, 82% of the Cs atoms populate their three-dimensional ground states. Our scheme improves the long-term stability of Raman sideband cooling in the presence of magnetic field drift and is thus suitable for cooling other trapped atoms or ions with abundant magnetic sublevels.

5.
Chemistry ; 30(10): e202302961, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38014860

RESUMEN

The single-functionality of traditional chemodynamic therapy (CDT) reagents usually limits the therapeutic efficacy of cancer treatment. Synergistic nanocomposites that involve cascade reaction provide a promising strategy to achieve satisfactory anticancer effects. Herein, a cuprous-based nanocomposite (CCS@GOx@HA) is fabricated, which owns the tumor targeting ability and can undergo tumor microenvironment responsive cascade reaction to enhance the tumor therapeutic efficiency significantly. Surface modification of nanocomposite with hyaluronic acid enables the targeted delivery of the nanocomposite to cancer cells. Acid-triggered decomposition of nanocomposite in cancer cell results in the release of Cu+ , Se2- and GOx. The Cu+ improves the Fenton-like reaction with endogenous H2 O2 to generate highly toxic • OH for CDT. While GOx can not only catalyze the in situ generation of endogenous H2 O2 , but also accelerate the consumption of intratumoral glucose to reduce nutrient supply in tumor site. In addition, Se2- further improves the therapeutic effects of CDT by upregulating the reactive oxygen species (ROS) in tumor cells. Meanwhile, the surface modification endows the nanocomposite the good water dispersibility and biocompatibility. Moreover, in vitro and in vivo experiments demonstrate satisfactory anti-cancer therapeutic performance by the synergistic cascade function of CCS@GOx@HA than CDT alone.


Asunto(s)
Nanocompuestos , Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Catálisis , Glucosa , Ácido Hialurónico , Nanocompuestos/uso terapéutico , Peróxido de Hidrógeno , Línea Celular Tumoral , Microambiente Tumoral
6.
Cerebrovasc Dis ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38377964

RESUMEN

BACKGROUND: Although guidelines recommend a target blood pressure 185-180/105-110 mmHg after mechanical thrombectomy for acute ischemic stroke (AIS), there is limited randomized evidence to support this level. We surveyed candidate institutions about the approach to blood pressure management in this patient group in preparation for inviting them to participate in the Enhanced Blood Pressure Control after Endovascular Thrombectomy for the Acute Ischemic Stroke Trial (ENCHANTED2/MT). METHODS: Physicians from a professional network of institutions that met mechanical thrombectomy qualification requirements were invited to participate in an online questionnaire covering basic clinical information as well as questions on blood pressure management. RESULTS: We invited 88 sites to participate with 44 (50%) ultimately joining the trial, and a total of 88 physicians finished the survey. The median number of annual mechanical thrombectomy cases performed per site was 89 [IQR 65-150]. Only 38 (43%) institutions strictly adhere to guidelines when managing the blood pressure of mechanical thrombectomy patients. The most popular blood pressure target for reperfusion patients was 140-160 mmHg (n=47, 53%), and <120 mmHg (n=28, 32%). Fewer hospital stroke beds (40 [21-57] vs. 60 [39-110], p = 0.01) and lower proportion of elevated blood pressure after mechanical thrombectomy (25% [10%-50%] vs. 50% [20%-70%], p = 0.02) were related to a more aggressive blood pressure target (<120 mmHg). Urapidil (n=82, 93%) and calcium channel blockers (CCBs) (n = 87, 99%), were the most widely used antihypertensive drugs, respectively. CONCLUSIONS: According to the survey, unstandardized blood pressure management protocols are performed in mechanical thrombectomy patients at institutions across China, which is different from prior survey from another country. More high-quality studies are needed to guide clinical practice.

7.
Cerebrovasc Dis ; 53(2): 176-183, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37598670

RESUMEN

INTRODUCTION: Whether time window affects the intravenous thrombolysis (IVT) effect before endovascular thrombectomy (EVT) is uncertain. We aimed to investigate the effect of different time windows (0-3 h and >3-4.5 h from stroke onset to randomization) on clinical outcomes of EVT with or without IVT in a subgroup analysis of DIRECT-MT. METHODS: The primary outcome was the 90-day modified Rankin Scale (mRS) according to time window. Logistic regression models were used to analyze the effect of different treatments (EVT with or without IVT) on outcomes within 0-3 h or >3-4.5 h. RESULTS: Among 656 patients who were included in the analysis, 282 (43.0%) were randomized within >3-4.5 h after stroke onset (125 without IVT and 157 with IVT), and 374 (57.0%) were randomized within 0-3 h (202 without IVT and 172 with IVT). We noted no significant difference in the thrombectomy-alone effect between the time window subgroups according to 90-day ordinal mRS (adjusted common odds ratio [acOR] in patients within 0-3 h: 1.06 [95% CI: 0.73-1.52], acOR in patients within >3-4.5 h: 1.19 [95% CI: 0.78-1.82]) and 90-day functional independence. Thrombectomy alone resulted in an increased proportion of patients with 90-day mRS 0-3 treated within >3-4.5 h (62.90 vs. 48.72%) but not within 0-3 h (65.84 vs. 63.95%). However, there was no interaction effect regarding all outcomes after the Bonferroni correction. CONCLUSIONS: Our results did not support thrombectomy-alone administration within 3-4.5 h in patients with acute ischemic stroke from large-vessel occlusion in the subgroup analysis of DIRECT-MT.


Asunto(s)
Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Trombectomía , Humanos , Procedimientos Endovasculares/métodos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía , Trombectomía/métodos , Terapia Trombolítica/métodos , Resultado del Tratamiento , Factores de Tiempo
8.
Neurocrit Care ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480608

RESUMEN

BACKGROUND: In this study, we aimed to investigate the risk factors and impact of poststroke pneumonia (PSP) on mortality and functional outcome in patients with acute ischemic stroke (AIS) after endovascular thrombectomy (EVT). METHODS: This was a post hoc analysis of a prospective randomized trial (Direct intraarterial thrombectomy in order to revascularize AIS patients with large-vessel occlusion efficiently in Chinese tertiary hospitals: a multicenter randomized clinical trial). Patients with AIS who completed EVT were evaluated for the occurrence of PSP during the hospitalization period and their modified Rankin Scale (mRS) scores at 90 days after AIS. Logistic regression analysis was conducted to investigate the independent predictors of PSP. Propensity score matching was conducted for the PSP and non-PSP groups by using the covariates resulting from the logistic regression analysis. The associations between PSP and outcomes were analyzed. The outcomes included 90-day poor functional outcome (mRS scores > 2), 90-day mortality, and early 2-week mortality. RESULTS: A total of 639 patients were enrolled, of whom 29.58% (189) developed PSP. Logistic regression analysis revealed that history of chronic heart failure (unadjusted odds ratio [OR] 2.011, 95% confidence interval [CI] 1.026-3.941; P = 0.042), prethrombectomy reperfusion on initial digital subtraction angiography (OR 0.394, 95% CI 0.161-0.964; P = 0.041), creatinine levels at admission (OR 1.008, 95% CI 1.000-1.016; P = 0.049), and National Institutes of Health Stroke Scale at 24 h (OR 1.023, 95% CI 1.007-1.039; P = 0.004) were independent risk factors for PSP. With propensity scoring matching, poor functional outcome (mRS > 2) was more common in patients with PSP than in patients without PSP (81.03% vs. 71.83%, P = 0.043) at 90 days after EVT. The early 2-week mortality of patients with PSP was lower (5.74% vs. 12.07%, P = 0.038). But there was no statistically significant difference in 90-day mortality between the PSP group and non-PSP group (22.41% vs. 14.94%, P = 0.074). The survivorship curve also shows no statistical significance (P = 0.088) between the two groups. CONCLUSIONS: Nearly one third of patients with AIS and EVT developed PSP. Heart failure, higher creatinine levels, prethrombectomy reperfusion, and National Institutes of Health Stroke Scale at 24 h were associated with PSP in these patients. PSP was associated with poor 90-day functional outcomes in patients with AIS treated with EVT.

9.
JAMA ; 331(9): 764-777, 2024 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-38324409

RESUMEN

Importance: The benefit of intravenous thrombolysis (IVT) for acute ischemic stroke declines with longer time from symptom onset, but it is not known whether a similar time dependency exists for IVT followed by thrombectomy. Objective: To determine whether the benefit associated with IVT plus thrombectomy vs thrombectomy alone decreases with treatment time from symptom onset. Design, Setting, and Participants: Individual participant data meta-analysis from 6 randomized clinical trials comparing IVT plus thrombectomy vs thrombectomy alone. Enrollment was between January 2017 and July 2021 at 190 sites in 15 countries. All participants were eligible for IVT and thrombectomy and presented directly at thrombectomy-capable stroke centers (n = 2334). For this meta-analysis, only patients with an anterior circulation large-vessel occlusion were included (n = 2313). Exposure: Interval from stroke symptom onset to expected administration of IVT and treatment with IVT plus thrombectomy vs thrombectomy alone. Main Outcomes and Measures: The primary outcome analysis tested whether the association between the allocated treatment (IVT plus thrombectomy vs thrombectomy alone) and disability at 90 days (7-level modified Rankin Scale [mRS] score range, 0 [no symptoms] to 6 [death]; minimal clinically important difference for the rates of mRS scores of 0-2: 1.3%) varied with times from symptom onset to expected administration of IVT. Results: In 2313 participants (1160 in IVT plus thrombectomy group vs 1153 in thrombectomy alone group; median age, 71 [IQR, 62 to 78] years; 44.3% were female), the median time from symptom onset to expected administration of IVT was 2 hours 28 minutes (IQR, 1 hour 46 minutes to 3 hours 17 minutes). There was a statistically significant interaction between the time from symptom onset to expected administration of IVT and the association of allocated treatment with functional outcomes (ratio of adjusted common odds ratio [OR] per 1-hour delay, 0.84 [95% CI, 0.72 to 0.97], P = .02 for interaction). The benefit of IVT plus thrombectomy decreased with longer times from symptom onset to expected administration of IVT (adjusted common OR for a 1-step mRS score shift toward improvement, 1.49 [95% CI, 1.13 to 1.96] at 1 hour, 1.25 [95% CI, 1.04 to 1.49] at 2 hours, and 1.04 [95% CI, 0.88 to 1.23] at 3 hours). For a mRS score of 0, 1, or 2, the predicted absolute risk difference was 9% (95% CI, 3% to 16%) at 1 hour, 5% (95% CI, 1% to 9%) at 2 hours, and 1% (95% CI, -3% to 5%) at 3 hours. After 2 hours 20 minutes, the benefit associated with IVT plus thrombectomy was not statistically significant and the point estimate crossed the null association at 3 hours 14 minutes. Conclusions and Relevance: In patients presenting at thrombectomy-capable stroke centers, the benefit associated with IVT plus thrombectomy vs thrombectomy alone was time dependent and statistically significant only if the time from symptom onset to expected administration of IVT was short.


Asunto(s)
Isquemia Encefálica , Fibrinolíticos , Accidente Cerebrovascular Isquémico , Trombectomía , Terapia Trombolítica , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Administración Intravenosa , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/cirugía , Fibrinolíticos/administración & dosificación , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía , Ensayos Clínicos Controlados Aleatorios como Asunto , Recuperación de la Función , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/complicaciones , Terapia Trombolítica/métodos , Tiempo de Tratamiento , Resultado del Tratamiento
10.
J Stroke Cerebrovasc Dis ; 33(8): 107814, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38880364

RESUMEN

AIMS: To investigate the association of the genetic predisposition of specific gut microbiotas with the clinical outcome of ischemic stroke. METHODS: We leveraged publicly available genome-wide association study (GWAS) data to perform Mendelian randomization (MR) analysis. The gut microbiota-related GWAS data from 18,340 individuals from the international consortium MiBioGen was used. The summary data for functional outcomes after ischemic stroke was obtained from the Genetics of Ischemic Stroke Functional Outcome (GISCOME) network meta-analysis. The primary outcomes were judged by the modified Rankin Scale (mRS). The principal analyses were conducted using the inverse-variance weighted (IVW) MR method. The Cochran's Q test, weighted median, MR-Egger regression, leave-one-SNP-out analysis, MR-Pleiotropy Residual Sum, and Outlier methods were adopted as sensitivity analyses. Furthermore, we performed bi-directional MR analysis and the MR Steiger directionality test to examine the direction of the causal relations. RESULTS: The results demonstrated that the genetic predisposition of genus Lactococcus, genus Ruminococcaceae NK4A214 group, family Peptostreptococcaceae, and genus Odoribacter was positively associated with favorable functional outcome after ischemic stroke. Genus Collinsella, genus Ruminococcaceae UCG005, genus Akkermansia, genus Eubacterium oxidoreducens group, and family Verrucomicrobiaceae were identified to be associated with worse functional outcomes after ischemic stroke. Our results showed no evidence of heterogeneity, directional pleiotropic effects, or collider bias, and the sensitivity of our analysis was acceptable. CONCLUSION: The genetic predisposition of different gut microbiotas was associated with the clinical outcome of ischemic stroke. Microbiota adjustment was a promising method to improve the clinical outcome of ischemic stroke.

11.
J Neuroradiol ; 51(1): 52-58, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37120144

RESUMEN

BACKGROUND: The DIRECT-MT trial showed that endovascular thrombectomy (EVT) alone was noninferior to EVT preceded by intravenous alteplase. However, the infusion of intravenous alteplase was uncompleted before the initiation of EVT in most cases of this trial. Therefore, the additional benefit and risk of over 2/3-dose intravenous alteplase pretreatment remain to be assessed. METHODS: We assessed patients with acute anterior circulation ischemic stroke who received EVT alone or with over 2/3-dose intravenous alteplase pretreatment from the DIRECT-MT trial. Patients were assigned to the thrombectomy-alone group and the alteplase pretreatment group. The primary outcome was the distribution of modified Rankin Scale (mRS) at 90 days. The interaction of treatment allocation and collateral capacity was assessed. RESULTS: A total of 393 patients (thrombectomy alone: 315; alteplase pretreatment: 78) were identified. The thrombectomy alone was comparable with alteplase pretreatment prior to the thrombectomy on the distribution of mRS at 90 days without significant effect modification by collateral capacity (adjusted common odds ratio (acOR), 1.12; 95% CI, 0.72-1.74; adjusted P for interaction = 0.83). Successful reperfusion before thrombectomy and the number of passes in the thrombectomy alone group differed significantly from the alteplase pretreatment group (2.6% vs. 11.5%; corrected P = 0.02 and 2 vs. 1; corrected P = 0.003). There was no interaction between treatment allocation and collateral capacity on all outcomes. CONCLUSIONS: EVT alone and EVT preceded by over 2/3-dose intravenous alteplase might have equal efficacy and safety for patients with acute anterior circulation large vessel occlusion, except for successful perfusion before thrombectomy and the number of passes.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Activador de Tejido Plasminógeno/uso terapéutico , Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/cirugía , Isquemia Encefálica/terapia , Procedimientos Endovasculares/efectos adversos , Trombectomía/efectos adversos , Terapia Trombolítica/efectos adversos , Resultado del Tratamiento
12.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(3): 281-284, 2024 May 30.
Artículo en Zh | MEDLINE | ID: mdl-38863094

RESUMEN

In magnetic resonance examination, the interaction between implants and the radio frequency (RF) fields induces heating in human tissue and may cause tissue damage. To assess the RF-induced heating of implants, three steps should be executed, including electromagnetic model construction, electromagnetic model validation, and virtual human body simulations. The crucial step of assessing RF-induced heating involves the construction of a test environment for electromagnetic model validation. In this study, a hardware environment, comprised of a RF generation system, electromagnetic field measurement system, and a robotic arm positioning system, was established. Furthermore, an automated control software environment was developed using a Python-based software development platform to enable the creation of a high-precision automated integrated test environment. The results indicate that the electric field generated in this test environment aligns well with the simulated electric field, making it suitable for assessing the RF-induced heating effects of implants.


Asunto(s)
Campos Electromagnéticos , Calor , Prótesis e Implantes , Ondas de Radio , Programas Informáticos , Humanos , Imagen por Resonancia Magnética
13.
Lancet ; 400(10363): 1585-1596, 2022 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-36341753

RESUMEN

BACKGROUND: The optimum systolic blood pressure after endovascular thrombectomy for acute ischaemic stroke is uncertain. We aimed to compare the safety and efficacy of blood pressure lowering treatment according to more intensive versus less intensive treatment targets in patients with elevated blood pressure after reperfusion with endovascular treatment. METHODS: We conducted an open-label, blinded-endpoint, randomised controlled trial at 44 tertiary-level hospitals in China. Eligible patients (aged ≥18 years) had persistently elevated systolic blood pressure (≥140 mm Hg for >10 min) following successful reperfusion with endovascular thrombectomy for acute ischaemic stroke from any intracranial large-vessel occlusion. Patients were randomly assigned (1:1, by a central, web-based program with a minimisation algorithm) to more intensive treatment (systolic blood pressure target <120 mm Hg) or less intensive treatment (target 140-180 mm Hg) to be achieved within 1 h and sustained for 72 h. The primary efficacy outcome was functional recovery, assessed according to the distribution in scores on the modified Rankin scale (range 0 [no symptoms] to 6 [death]) at 90 days. Analyses were done according to the modified intention-to-treat principle. Efficacy analyses were performed with proportional odds logistic regression with adjustment for treatment allocation as a fixed effect, site as a random effect, and baseline prognostic factors, and included all randomly assigned patients who provided consent and had available data for the primary outcome. The safety analysis included all randomly assigned patients. The treatment effects were expressed as odds ratios (ORs). This trial is registered at ClinicalTrials.gov, NCT04140110, and the Chinese Clinical Trial Registry, 1900027785; recruitment has stopped at all participating centres. FINDINGS: Between July 20, 2020, and March 7, 2022, 821 patients were randomly assigned. The trial was stopped after review of the outcome data on June 22, 2022, due to persistent efficacy and safety concerns. 407 participants were assigned to the more intensive treatment group and 409 to the less intensive treatment group, of whom 404 patients in the more intensive treatment group and 406 patients in the less intensive treatment group had primary outcome data available. The likelihood of poor functional outcome was greater in the more intensive treatment group than the less intensive treatment group (common OR 1·37 [95% CI 1·07-1·76]). Compared with the less intensive treatment group, the more intensive treatment group had more early neurological deterioration (common OR 1·53 [95% 1·18-1·97]) and major disability at 90 days (OR 2·07 [95% CI 1·47-2·93]) but there were no significant differences in symptomatic intracerebral haemorrhage. There were no significant differences in serious adverse events or mortality between groups. INTERPRETATION: Intensive control of systolic blood pressure to lower than 120 mm Hg should be avoided to prevent compromising the functional recovery of patients who have received endovascular thrombectomy for acute ischaemic stroke due to intracranial large-vessel occlusion. FUNDING: The Shanghai Hospital Development Center; National Health and Medical Research Council of Australia; Medical Research Futures Fund of Australia; China Stroke Prevention; Shanghai Changhai Hospital, Science and Technology Commission of Shanghai Municipality; Takeda China; Hasten Biopharmaceutic; Genesis Medtech; Penumbra.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Adolescente , Adulto , Isquemia Encefálica/tratamiento farmacológico , Accidente Cerebrovascular/terapia , Presión Sanguínea/fisiología , Resultado del Tratamiento , China/epidemiología , Trombectomía/efectos adversos , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía
14.
N Engl J Med ; 382(21): 1981-1993, 2020 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-32374959

RESUMEN

BACKGROUND: In acute ischemic stroke, there is uncertainty regarding the benefit and risk of administering intravenous alteplase before endovascular thrombectomy. METHODS: We conducted a trial at 41 academic tertiary care centers in China to evaluate endovascular thrombectomy with or without intravenous alteplase in patients with acute ischemic stroke. Patients with acute ischemic stroke from large-vessel occlusion in the anterior circulation were randomly assigned in a 1:1 ratio to undergo endovascular thrombectomy alone (thrombectomy-alone group) or endovascular thrombectomy preceded by intravenous alteplase, at a dose of 0.9 mg per kilogram of body weight, administered within 4.5 hours after symptom onset (combination-therapy group). The primary analysis for noninferiority assessed the between-group difference in the distribution of the modified Rankin scale scores (range, 0 [no symptoms] to 6 [death]) at 90 days on the basis of a lower boundary of the 95% confidence interval of the adjusted common odds ratio equal to or larger than 0.8. We assessed various secondary outcomes, including death and reperfusion of the ischemic area. RESULTS: Of 1586 patients screened, 656 were enrolled, with 327 patients assigned to the thrombectomy-alone group and 329 assigned to the combination-therapy group. Endovascular thrombectomy alone was noninferior to combined intravenous alteplase and endovascular thrombectomy with regard to the primary outcome (adjusted common odds ratio, 1.07; 95% confidence interval, 0.81 to 1.40; P = 0.04 for noninferiority) but was associated with lower percentages of patients with successful reperfusion before thrombectomy (2.4% vs. 7.0%) and overall successful reperfusion (79.4% vs. 84.5%). Mortality at 90 days was 17.7% in the thrombectomy-alone group and 18.8% in the combination-therapy group. CONCLUSIONS: In Chinese patients with acute ischemic stroke from large-vessel occlusion, endovascular thrombectomy alone was noninferior with regard to functional outcome, within a 20% margin of confidence, to endovascular thrombectomy preceded by intravenous alteplase administered within 4.5 hours after symptom onset. (Funded by the Stroke Prevention Project of the National Health Commission of the People's Republic of China and the Wu Jieping Medical Foundation; DIRECT-MT ClinicalTrials.gov number, NCT03469206.).


Asunto(s)
Fibrinolíticos/uso terapéutico , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/cirugía , Trombectomía/métodos , Activador de Tejido Plasminógeno/uso terapéutico , Anciano , Hemorragia Cerebral/etiología , China , Terapia Combinada , Intervalos de Confianza , Procedimientos Endovasculares , Femenino , Fibrinolíticos/efectos adversos , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Reperfusión/métodos , Trombectomía/efectos adversos , Tiempo de Tratamiento , Activador de Tejido Plasminógeno/efectos adversos , Resultado del Tratamiento
15.
Planta ; 257(4): 75, 2023 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-36879140

RESUMEN

MAIN CONCLUSION: Species have plasticity across altitude gradients in leaf morphology and function, and their response to high altitude conditions was mainly reflected in leaf cell metabolism and gas exchange. Leaf morphological and functional adaptation to altitude has received research attention in recent years, but there are no studies for forage legumes. Here we report differences in 39 leaf morphology and functional traits of three leguminous forages (alfalfa, sainfoin and perennial vetch) at three sites in Gansu Province, China, ranging from 1768 to 3074 m altitude to provide information for potential use in breeding programmes. With increasing altitude, plant water status increased, reflecting increase in soil water content and decreased average temperature, which lead to leaf intercellular CO2 concentration. Stomatal conductance and evapotranspiration increased significantly but water-use efficiency decreased. At high altitude, ΦPSII decreased but non-photochemical quenching and chlorophyll a:b ratio increased while spongy mesophyll tissue and leaf thickness increased. These changes may be due to UV or low-temperature damage of leaf protein and metabolic cost of plant protection or defence responses. Contrary to many other studies, leaf mass per area decreased significantly at higher altitude. This was consistent with predictions under the worldwide leaf economic spectrum on the basis that soil nutrients increased with increasing altitude. The key species differences were more irregularly shaped epidermal cells and larger stomatal size in perennial vetch compared to alfalfa or sainfoin that enhanced gas exchange and photosynthesis by generating mechanical force, increasing guard cell turgor, and promoting stomatal operation. The lower adaxial stomatal density also enhanced water-use efficiency. These adaptations might confer perennial vetch an advantage in environments with extreme diurnal temperature fluctuation or in frigid conditions.


Asunto(s)
Medicago sativa , Vicia , Altitud , Clorofila A , Fitomejoramiento , Verduras , Hojas de la Planta
16.
Phys Rev Lett ; 130(17): 173601, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37172253

RESUMEN

We experimentally demonstrate strong coupling between a one-dimensional (1D) single-atom array and a high-finesse miniature cavity. The atom array is obtained by loading single atoms into a 1D optical tweezer array with dimensions of 1×11. Therefore, a deterministic number of atoms is obtained, and the atom number is determined by imaging the atom array on a CCD camera in real time. By precisely controlling the position and spacing of the atom array in the high finesse Fabry-Perot cavity, all the atoms in the array are strongly coupled to the cavity simultaneously. The vacuum Rabi splitting spectra are discriminated for deterministic atom numbers from 1 to 8, and the sqrt[N] dependence of the collective enhancement of the coupling strength on atom number N is validated at the single-atom level.

17.
Langmuir ; 39(10): 3668-3677, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36854143

RESUMEN

Gelatin (GE) is a renewable biopolymer with abundant active groups that are beneficial for manufacturing functional biomaterials via GE modification. An antibacterial fibrous GE film was prepared by electrospinning the modified GE in an aqueous solution. The original GE was modified by reacting it with N,N-dimethyl epoxypropyl octadecyl ammonium chloride (QAS), and then it was cross-linked with transglutaminase (TGase). FTIR analysis illustrated that QAS was grafted onto GE through the epoxy ring-opening reaction, and the modification did not influence the main GE skeleton structure. The investigation of the solution properties showed that the grafted cationic QAS group was the main factor that decreased the surface tension of the solution, increased the electrical conductivity of the solution, and endowed GE with antibacterial activity. TGase cross-linking clearly influenced the rheological properties such that the flow pattern of the spinning solution varied from Newton-type to shear thinning, and the aqueous solution of GE-QAS-TGs transformed from liquid-like to solid-like and even induced gelatinization with increasing TGase content. A satisfactory fibrous morphology of 200-500 nm diameter was obtained using a homemade instrument under the optimized electrospinning conditions of a temperature of 35 °C, a distance between electrodes of 12 cm, and a voltage of 15 kV. The study of film properties showed that the antibacterial activity of the fibrous GE film depended only on the grafted quaternary ammonium, whereas the thermostability, wettability, and permeability were greatly influenced by both the TGase cross-linking and film-forming methods. Cytotoxicity was tested using the CCK-8 and live/dead kit staining methods in vitro, which showed that the modified GE had good biocompatibility.


Asunto(s)
Materiales Biocompatibles , Gelatina , Gelatina/química , Humectabilidad , Tensión Superficial , Agua/química , Antibacterianos/toxicidad , Antibacterianos/química
18.
Eur Radiol ; 33(4): 2629-2637, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36502458

RESUMEN

OBJECTIVE: Some patients with acute large vessel occlusion (LVO) presented imaging mismatch, low Alberta Stroke Program Early CT Score (ASPECTS) with small ischemic core, or high ASPECTS with large ischemic core. The study was designed to explore whether patients with imaging mismatch could benefit from endovascular treatment (EVT). METHODS: We retrospectively reviewed patients with LVO treated with EVT in our center from March 2018 to Jul 2020. Patients were divided into three groups, imaging mismatch, small ischemic core, and large ischemic core groups. Pooled analyses based on stroke onset to treatment time were done. Multivariate regression analysis was performed to explore the factors for good outcomes. RESULTS: Sixty-eight of 419 patients with LVO presented with imaging mismatch, and 35 of those (51%) achieved good outcomes after EVT at 90-day. No significant differences were noted in good outcomes and symptomatic intracranial hemorrhage (sICH) between patients with imaging mismatch and small ischemic core. Compared with large ischemic core, patients with imaging mismatch presented lower risk of sICH (95% confidence interval (CI) 0.04-0.75, p = 0.011) within 6 h and higher proportion of good outcomes (95% CI 0.37-0.82, p = 0.002) at 6 to 24 h. Baseline NIHSS (odds ratio (OR) = 0.91, 95% CI 0.88-0.95)), ASPECTS (OR = 1.14, 95% CI 1.01-1.29), ischemic core (OR = 0.99, 95% CI 0.98-1.00), and sICH (OR = 61.61, 95% CI 8.09-461.32) were associated with good outcomes. CONCLUSIONS: Patients with imaging mismatch treated within 24 h could benefit from EVT and without increasing the risk of sICH. KEY POINTS: • Patients with imaging mismatch between ASPECTS and ischemic core could achieve good outcomes after endovascular treatment. • Compared with large ischemic core, patients with imaging mismatch presented lower risk of symptomatic hemorrhage within 6 h and higher proportion of good outcomes within 6-24 h. • Baseline NIHSS score, ASPECTS, ischemic core, and symptomatic intracranial hemorrhage were associated with good outcomes.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Humanos , Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/terapia , Isquemia Encefálica/complicaciones , Estudios Retrospectivos , Alberta/epidemiología , Resultado del Tratamiento , Trombectomía/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/terapia , Accidente Cerebrovascular/complicaciones , Hemorragias Intracraneales/etiología , Tomografía Computarizada por Rayos X , Imagen de Perfusión , Procedimientos Endovasculares/métodos
19.
Eur Radiol ; 33(1): 135-143, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35849176

RESUMEN

OBJECTIVES: Predictors of malignant middle cerebral artery infarction (mMCAi) in patients after intravenous thrombolysis were well documented, but the risk factors of mMCAi after endovascular thrombectomy (EVT) were not fully explored. Therefore, the present study aimed to investigate the predictors of mMCAi after EVT in stroke patients. METHODS: This was a secondary analysis of the DIRECT-MT trial. Patients who underwent EVT for the occlusions of MCA and/or intracranial internal carotid artery were analyzed. Primary outcome was the occurrence of mMCAi after EVT. Demographic, clinical, imaging, and treatment data were recorded, and multivariate logistic regression analysis was used to identify independent predictors. All of the candidate predictors were included, and forward elimination was applied to establish the most effective predictive model. Predictive ability and calibration of the model were assessed using the area under the receiver operating characteristic curve (AUC) and Hosmer-Lemeshow test, respectively. RESULTS: Of 559 enrolled patients, 74 (13.2%) patients developed mMCAi. Predictors of mMCAi included unsuccessful reperfusion, higher serum glucose, lower Alberta Stroke Project Early Computed Tomography Change Score (ASPECTS), higher clot burden score (CBS), lower collateral score, and higher pass number of thrombectomy device. AUC of predictive model integrating all independent variables was 0.836. The Hosmer-Lemeshow test showed appropriate calibration (p = 0.859). CONCLUSIONS: Reperfusion, serum glucose, ASPECTS, CBS, collateral, and pass number of thrombectomy device were associated with the occurrence of mMCAi in stroke patients after EVT, while alteplase treatment was not. Our findings might facilitate the early identification and management of stroke patients at a high risk of mMCAi. KEY POINTS: • A total of 13.2% of stroke patients with large vessel occlusion of anterior circulation developed mMCAi after EVT. • The occurrence of mMCAi had a definite negative impact on the outcome for stroke patients. • Reperfusion, serum glucose, ASPECTS, CBS, collateral score, and the pass number of thrombectomy device were associated with the occurrence of mMCAi after EVT in stroke patients.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular , Humanos , Isquemia Encefálica/etiología , Procedimientos Endovasculares/métodos , Glucosa , Infarto de la Arteria Cerebral Media/diagnóstico por imagen , Infarto de la Arteria Cerebral Media/terapia , Estudios Retrospectivos , Accidente Cerebrovascular/etiología , Trombectomía/métodos , Resultado del Tratamiento , Ensayos Clínicos como Asunto , Análisis de Datos Secundarios
20.
Inorg Chem ; 62(16): 6458-6466, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-37043341

RESUMEN

Selective anion recognition and extraction in aqueous media is a challenging research topic, and the anion-π interaction is an undetermined solution for the development of anion sorbent materials with better affinity and selectivity. Here, noncovalent anion-π interaction was introduced as the driving force for this purpose. A cage-based 2D cationic metal-organic framework, IPM-21, is featured with porous channels formed by complementary V-shape electron-deficient cavities. This 3D rhombic electron-deficient cavity can bind two anions with the clipped π-acidic surfaces, exhibiting much higher affinity toward ReO4- due to the strong complementary effect. This cavity was forced to expand its opening size to seamlessly adopt the ReO4- anion with a large volume. Experimental results found that the binding energy of IPM-21 with ReO4- is around 2.3 kJ/mol higher than that with ClO4-. Parts per million levels of the ReO4- anion in aqueous media can be effectively extracted by IPM-21 with a removal up to 99%, even with mixed competing anions. IPM-21 can be easily recycled and reused by treatment with high concentration aqueous NaClO4. Due to the extremely low interlamellar interaction, the IPM-21 crystal exhibited enhanced ReO4- extraction performance with the recycling times due to self-exfoliation; as a result, ultrathin IPM-21 nanosheets with large lateral sizes were produced in this process.

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