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1.
JAMA Neurol ; 80(8): 851-859, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37358859

RESUMO

Importance: DL-3-n-butylphthalide (NBP) is a drug for treating acute ischemic stroke and may play a neuroprotective role by acting on multiple active targets. The efficacy of NBP in patients with acute ischemic stroke receiving reperfusion therapy remains unknown. Objective: To assess the efficacy and safety of NBP in patients with acute ischemic stroke receiving reperfusion therapy of intravenous thrombolysis and/or endovascular treatment. Design, Setting, and Participants: This multicenter, double-blind, placebo-controlled, parallel randomized clinical trial was conducted in 59 centers in China with 90-day follow-up. Of 1236 patients with acute ischemic stroke, 1216 patients 18 years and older diagnosed with acute ischemic stroke with a National Institutes of Health Stroke Scale score ranging from 4 to 25 who could start the trial drug within 6 hours from symptom onset and received either intravenous recombinant tissue plasminogen activator (rt-PA) or endovascular treatment or intravenous rt-PA bridging to endovascular treatment were enrolled, after excluding 20 patients who declined to participate or did not meet eligibility criteria. Data were collected from July 1, 2018, to May 22, 2022. Interventions: Within 6 hours after symptom onset, patients were randomized to receive NBP or placebo in a 1:1 ratio. Main Outcomes and Measures: The primary efficacy outcome was the proportion of patients with a favorable outcome based on 90-day modified Rankin Scale score (a global stroke disability scale ranging from 0 [no symptoms or completely recovered] to 6 [death]) thresholds of 0 to 2 points, depending on baseline stroke severity. Results: Of 1216 enrolled patients, 827 (68.0%) were men, and the median (IQR) age was 66 (56-72) years. A total of 607 were randomly assigned to the butylphthalide group and 609 to the placebo group. A favorable functional outcome at 90 days occurred in 344 patients (56.7%) in the butylphthalide group and 268 patients (44.0%) in the placebo group (odds ratio, 1.70; 95% CI, 1.35-2.14; P < .001). Serious adverse events within 90 days occurred in 61 patients (10.1%) in the butylphthalide group and 73 patients (12.0%) in the placebo group. Conclusions and Relevance: Among patients with acute ischemic stroke receiving intravenous thrombolysis and/or endovascular treatment, NBP was associated with a higher proportion of patients achieving a favorable functional outcome at 90 days compared with placebo. Trial Registration: ClinicalTrials.gov Identifier: NCT03539445.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Idoso , Feminino , Ativador de Plasminogênio Tecidual/uso terapêutico , Fibrinolíticos/uso terapêutico , AVC Isquêmico/tratamento farmacológico , Resultado do Tratamento , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/complicações
2.
N Engl J Med ; 387(15): 1373-1384, 2022 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-36239645

RESUMO

BACKGROUND: The effects and risks of endovascular thrombectomy 6 to 24 hours after stroke onset due to basilar-artery occlusion have not been extensively studied. METHODS: In a trial conducted over a 5-year period in China, we randomly assigned, in a 1:1 ratio, patients with basilar-artery stroke who presented between 6 to 24 hours after symptom onset to receive either medical therapy plus thrombectomy or medical therapy only (control). The original primary outcome, a score of 0 to 4 on the modified Rankin scale (range, 0 to 6, with a score of 0 indicating no disability, 4 moderately severe disability, and 6 death) at 90 days, was changed to a good functional status (a modified Rankin scale score of 0 to 3, with a score of 3 indicating moderate disability). Primary safety outcomes were symptomatic intracranial hemorrhage at 24 hours and 90-day mortality. RESULTS: A total of 217 patients (110 in the thrombectomy group and 107 in the control group) were included in the analysis; randomization occurred at a median of 663 minutes after symptom onset. Enrollment was halted at a prespecified interim analysis because of the superiority of thrombectomy. Thrombolysis was used in 14% of the patients in the thrombectomy group and in 21% of those in the control group. A modified Rankin scale score of 0 to 3 (primary outcome) occurred in 51 patients (46%) in the thrombectomy group and in 26 (24%) in the control group (adjusted rate ratio, 1.81; 95% confidence interval [CI], 1.26 to 2.60; P<0.001). The results for the original primary outcome of a modified Rankin scale score of 0 to 4 were 55% and 43%, respectively (adjusted rate ratio, 1.21; 95% CI, 0.95 to 1.54). Symptomatic intracranial hemorrhage occurred in 6 of 102 patients (6%) in the thrombectomy group and in 1 of 88 (1%) in the control group (risk ratio, 5.18; 95% CI, 0.64 to 42.18). Mortality at 90 days was 31% in the thrombectomy group and 42% in the control group (adjusted risk ratio, 0.75; 95% CI, 0.54 to 1.04). Procedural complications occurred in 11% of the patients who underwent thrombectomy. CONCLUSIONS: Among patients with stroke due to basilar-artery occlusion who presented 6 to 24 hours after symptom onset, thrombectomy led to a higher percentage with good functional status at 90 days than medical therapy but was associated with procedural complications and more cerebral hemorrhages. (Funded by the Chinese National Ministry of Science and Technology; BAOCHE ClinicalTrials.gov number, NCT02737189.).


Assuntos
Arteriopatias Oclusivas , Artéria Basilar , Procedimentos Endovasculares , Acidente Vascular Cerebral , Trombectomia , Humanos , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/tratamento farmacológico , Arteriopatias Oclusivas/mortalidade , Arteriopatias Oclusivas/cirurgia , Artéria Basilar/efeitos dos fármacos , Artéria Basilar/cirurgia , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/etiologia , Isquemia Encefálica/mortalidade , Isquemia Encefálica/cirurgia , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Hemorragias Intracranianas/induzido quimicamente , Hemorragias Intracranianas/etiologia , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Fatores de Tempo , Resultado do Tratamento
3.
ACS Nano ; 16(10): 16584-16597, 2022 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-36001338

RESUMO

Materials in nature feature versatile and programmable interactions to render macroscopic architectures with multiscale structural arrangements. By rationally combining metal-carboxylate and metal-organophosphate coordination interactions, Au25(MHA)18 (MHA, 6-mercaptohexanoic acid) nanocluster self-assembled structural color coating films and phytic acid (PA)-metal coordination complexes are sequentially constructed on the surface of titanium implants. The Lewis acid-base coordination principle applies for these metal-organic coordination networks. The isotropic arrangement of nanoclusters with a short-range order is investigated via grazing incidence wide-angle X-ray scattering. The integration of robust M-O (M = Ti, Zr, Hf) and labile Cu-O coordination bonds with high connectivity of Au25(MHA)18 nanoclusters enables these artificial photonic structures to achieve a combination of mechanical stability and bacteriostatic activity. Moreover, the colorless and transparent PA-metal complex layer allows the viewing of the structural color and surface wettability switching to hydrophilic and makes feasible the interfacial biomineralization of hydroxyapatite. Collectively, these modular metal-organic coordination-driven assemblies are predictive and rational material design strategies with tunable hierarchy and diversity. The complete metal-organic architectures will not only help improve the physicochemical properties of the bone-implant interface with synergistic antibacterial and osseointegration activities but also can boost surface engineering of medical metal implants.


Assuntos
Complexos de Coordenação , Titânio , Titânio/farmacologia , Titânio/química , Complexos de Coordenação/química , Biomimética , Ácido Fítico , Ácidos de Lewis , Durapatita , Antibacterianos/farmacologia , Antibacterianos/química , Organofosfatos , Propriedades de Superfície
4.
Front Pharmacol ; 13: 860546, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35517821

RESUMO

Gasdermin E (GSDME) is one of the executors of pyroptosis, a type of programmed lytic cell death, which can be triggered by caspase-3 activation upon stimulation. Silenced GSDME expression due to promoter hypermethylation is associated with gastric cancer (GC), which is confirmed in the present study by bioinformatics analysis and methylation-specific PCR (MSP) test of GC cell lines and clinical samples. GC cell lines and mouse xenograft models were used to investigate the pyroptosis-inducing effect of the common cholesterol-depleting, drug simvastatin (SIM), allied with upregulating GSDME expression by doxycycline (DOX)- inducible Tet-on system or DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine (5-Aza-CdR). Cell viability assessment and xenograft tumour growth demonstrated that the tumour inhibition effects of SIM can be enhanced by elevated GSDME expression. Morphological examinations and assays measuring lactate dehydrogenase (LDH) release and caspase-3/GSDME protein cleavage underlined the stimulation of pyroptosis as an important mechanism. Using short hairpin RNA (shRNA) knockdown of caspase-3 or GSDME, and caspase-3-specific inhibitors, we provided evidence of the requirement of caspase-3/GSDME in the pyroptosis process triggered by SIM. We conclude that reactivating GSDME expression and thereby inducing cancer cell-specific pyroptosis could be a potential therapeutic strategy against GC.

5.
Acta Biomater ; 143: 418-427, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35219867

RESUMO

Helicobacter pylori is a causative factor of various gastrointestinal tract diseases. As clinical antibiotic-based therapy for H. pylori infection might induce bacterial drug resistance, the in vivo eradication of H. pylori remains a huge challenge. In the present study, monoclonal antibody-conjugated liposomes loaded with indocyanine green (ICG) (HpAb-LiP-ICG) were successfully developed for targeted photoacoustic (PA) imaging-guided sonodynamic therapy (SDT) of H. pylori infection in vivo. HpAb-LiP-ICG showed high stability and favorable biocompatibility in acidic environment (pH 1.5) and was used for treating H. pylori-infected mice through oral administration. PA imaging showed that HpAb-LiP-ICG could precisely recognize and target H. pylori in the stomach. Following the targeting of HpAb-LiP-ICG to H. pylori, ICG was activated to generate singlet oxygen (1O2) for eliminating H. pylori under ultrasound (US) irradiation. Pathological analysis revealed that the HpAb-LiP-ICG-mediated SDT eradicated H. pylori without unintended toxicity to normal tissues. In conclusion, the HpAb-LiP-ICG-mediated SDT might shed new light on treating H. pylori infection, indicating the clinical translational prospects of this therapy in near future. STATEMENT OF SIGNIFICANCE: Traditional antibiotic-based therapy for Helicobacter pylori infections suffers from the risk of drug resistance. To meet this challenge, a monoclonal antibody-conjugated nanoliposome loaded with indocyanine green (ICG) (HpAb-LiP-ICG) was successfully developed, and efficient eradication of H. pylori was achieved in vivo by visual sonodynamic therapy (SDT). HpAb-LiP-ICG exhibited biocompatibility, targeting, and stability in the acidic microenvironment. Under ultrasound (US) irradiation in vitro, the HpAb-LiP-ICG nanoliposomes accumulated on the surface of H. pylori were activated to produce adequate singlet oxygen (1O2) to eliminate H. pylori. Gastric mucous tissues infected with H. pylori recovered to the normal state after HpAb-LiP-ICG-mediated SDT without side effects, thus highlighting the clinical translational prospects of the prepared HpAb-LiP-ICG nanoliposome in near future.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Técnicas Fotoacústicas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anticorpos Monoclonais , Infecções por Helicobacter/tratamento farmacológico , Verde de Indocianina/farmacologia , Lipossomos , Camundongos , Oxigênio Singlete
6.
J Neurointerv Surg ; 14(9): 868-874, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34599086

RESUMO

BACKGROUD: The goal of this study was to determine if the choice of imaging paradigm performed in the emergency department influences the procedural or clinical outcomes after mechanical thrombectomy (MT). METHODS: This is a retrospective comparative outcome study which was conducted from the ANGEL-ACT registry. Comparisons were made between baseline characteristics and clinical outcomes of patients with acute ischemic stroke undergoing MT with non-contrast head computed tomography (NCHCT) alone versus patients undergoing NCHCT plus non-invasive vessel imaging (NVI) (including CT angiography (with or without CT perfusion) and magnetic resonance angiography). The primary outcome was the modified Rankin Scale (mRS) score at 90 days. Secondary outcomes included change in mRS score from baseline to 90 days, the proportions of mRS 0-1, 0-2, and 0-3, and dramatic clinical improvement at 24 hours. The safety outcomes were any intracranial hemorrhage (ICH), symptomatic ICH, and mortality within 90 days. RESULTS: A total of 894 patients met the inclusion criteria; 476 (53%) underwent NCHCT alone and 418 (47%) underwent NCHCT + NVI. In the NCHCT alone group, the door-to-reperfusion time was shorter by 47 min compared with the NCHCT + NVI group (219 vs 266 min, P<0.001). Patients in the NCHCT alone group showed a smaller increase in baseline mRS score at 90 days (median 3 vs 2 points; P=0.004) after adjustment. There were no significant differences between groups in the remaining clinical outcomes. CONCLUSIONS: In patients selected for MT using NCHCT alone versus NCHCT + NVI, there were improved procedural outcomes and smaller increases in baseline mRS scores at 90 days.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Humanos , Hemorragias Intracranianas/etiologia , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Sistema de Registros , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Front Neurol ; 12: 666919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34177774

RESUMO

Purpose: Tirofiban administration to acute ischemic stroke patients undergoing mechanical thrombectomy with preceding intravenous thrombolysis remains controversial. The aim of the current study was to evaluate the safety and efficacy of low-dose tirofiban during mechanical thrombectomy in patients with preceding intravenous thrombolysis. Methods: Patients with acute ischemic stroke undergoing mechanical thrombectomy and preceding intravenous thrombolysis were derived from "ANGEL-ACT," a multicenter, prospective registry study. The patients were dichotomized into tirofiban and non-tirofiban groups based on whether tirofiban was administered. Propensity score matching was used to minimize case bias. The primary safety endpoint was symptomatic intracerebral hemorrhage (sICH), defined as an intracerebral hemorrhage (ICH) associated with clinical deterioration as determined by the Heidelberg Bleeding Classification. All ICHs and hemorrhage types were recorded. Clinical outcomes included successful recanalization, dramatic clinical improvement, functional independence, and mortality at the 3-month follow-up timepoint. Successful recanalization was defined as a modified Thrombolysis in Cerebral Ischemia score of 2b or 3. Dramatic clinical improvement at 24 h was defined as a reduction in NIH stroke score of ≥10 points compared with admission, or a score ≤1. Functional independence was defined as a Modified Rankin Scale (mRS) score of 0-2 at 3-months. Results: The study included 201 patients, 81 in the tirofiban group and 120 in the non-tirofiban group, and each group included 68 patients after propensity score matching. Of the 201 patients, 52 (25.9%) suffered ICH, 15 (7.5%) suffered sICH, and 18 (9.0%) died within 3-months. The median mRS was 3 (0-4), 99 (49.3%) achieved functional independence. There were no statistically significant differences in safety outcomes, efficacy outcomes on successful recanalization, dramatic clinical improvement, or 3-month mRS between the tirofiban and non-tirofiban groups (all p > 0.05). Similar results were obtained after propensity score matching. Conclusion: In acute ischemic stroke patients who underwent mechanical thrombectomy and preceding intravenous thrombolysis, low-dose tirofiban was not associated with increased risk of sICH or ICH. Further randomized clinical trials are needed to confirm the effects of tirofiban in patients undergoing bridging therapy.

9.
Stroke ; 52(4): 1203-1212, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33596674

RESUMO

BACKGROUND AND PURPOSE: The benefit of endovascular treatment (EVT) for large vessel occlusion in clinical practice in developing countries like China needs to be confirmed. The aim of the study was to determine whether the benefit of EVT for acute ischemic stroke in randomized trials could be generalized to clinical practice in Chinese population. METHODS: We conducted a prospective registry of EVT at 111 centers in China. Patients with acute ischemic stroke caused by imaging-confirmed intracranial large vessel occlusion and receiving EVT were included. The primary outcome was functional independence at 90 days defined as a modified Rankin Scale score of 0 to 2. Outcomes of specific subgroups in the anterior circulation were reported and logistic regression was performed to predict the primary outcome. RESULTS: Among the 1793 enrolled patients, 1396 (77.9%) had anterior circulation large vessel occlusion (median age, 66 [56-73] years) and 397 (22.1%) had posterior circulation large vessel occlusion (median age, 64 [55-72] years). Functional independence at 90 days was reached in 45% and 44% in anterior and posterior circulation groups, respectively. For anterior circulation population, underlying intracranial atherosclerotic disease was identified in 29% of patients, with higher functional independence at 90 days (52% versus 44%; P=0.0122) than patients without intracranial atherosclerotic disease. In the anterior circulation population, after adjusting for baseline characteristics, procedure details, and early outcomes, the independent predictors for functional independence at 90 days were age <66 years (odds ratio [OR], 1.733 [95% CI, 1.213-2.476]), time from onset to puncture >6 hours (OR, 1.536 [95% CI, 1.065-2.216]), local anesthesia (OR, 2.194 [95% CI, 1.325-3.633]), final modified Thrombolysis in Cerebral Infarction 2b/3 (OR, 2.052 [95% CI, 1.085-3.878]), puncture-to-reperfusion time ≤1.5 hours (OR, 1.628 [95% CI, 1.098-2.413]), and National Institutes of Health Stroke Scale score 24 hours after the procedure <11 (OR, 9.126 [95% CI, 6.222-13.385]). CONCLUSIONS: Despite distinct characteristics in the Chinese population, favorable outcome of EVT can be achieved in clinical practice in China. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03370939.


Assuntos
Procedimentos Endovasculares/métodos , AVC Isquêmico/cirurgia , Idoso , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/cirurgia , China , Feminino , Humanos , AVC Isquêmico/etiologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Resultado do Tratamento
10.
Colloids Surf B Biointerfaces ; 197: 111430, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33125976

RESUMO

Affinity membrane is widely employed to promote specific adsorption of toxins and reduce the blood purification therapeutic time. However, it suffers from insufficient toxin binding and low hemocompatibility. Herein, a novel anticoagulant affinity membrane (AAM) was developed to clear bilirubin from human blood in a pore-flow-through way. Firstly, a nylon net membrane with a regularly arranged pore as the matrix was coated with poly(pyrrole-3-carboxylic acid) via chemical vapor deposition (CVD) method. Then, poly(L-arginine) (PLA) as a highly specific ligand of bilirubin, was immobilized onto the surface of the composited membrane after the modification of heparin. Owing to the 3-dimensional molecular architecture of PLA, up to 86.1 % of bilirubin was efficiently cleared. Besides, the AAM exhibited effective anticoagulant activity in the measurement of clotting time, with suppressed thrombus formation, low hemolysis ratio, minimized platelet and leukocyte adhesion, and excellent biosafety. Therefore, the AAM has enormous potential in blood purification therapy for enhancing hemocompatibility and bilirubin removal.


Assuntos
Anticoagulantes , Trombose , Adsorção , Anticoagulantes/farmacologia , Bilirrubina , Heparina , Humanos , Teste de Materiais , Adesividade Plaquetária
11.
Nanoscale ; 11(46): 22237-22242, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31740916

RESUMO

We developed a versatile and modular method for cytosolic protein delivery through metal ion-induced co-assembly of gold nanoclusters and proteins into supramolecular assemblies. The versatility and high efficiency of this strategy to assemble and deliver various proteins into living cells were demonstrated. Importantly, the activity of proteins was maintained during the delivery. This modular approach provides an exciting and promising new nano-platform for cytosolic protein delivery.


Assuntos
Citosol/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Proteínas/metabolismo , Animais , Cálcio/química , Bovinos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Glutationa/química , Humanos , Nanopartículas Metálicas/toxicidade , Microscopia de Fluorescência , Proteínas/química , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo
12.
Adv Healthc Mater ; 8(15): e1900192, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31197956

RESUMO

Emerging Fenton-like activity of copper ions has inspired great exploration for tumor microenvironment-activated tumor therapy due to the toxic ·OH production for chemodynamic therapy and extra oxygen generation for photodynamic therapy (PDT). Still, the ·OH produced by copper ions is not satisfied even when copper ions are placed in a low pH environment (pH ≈ 5.0). To amplify its Fenton-like activity, in this work, one kind of Cu2+ -protein self-assemblies (C-m-ABs) loaded with photosensitizer indocyanine green (ICG) is constructed, which can catalyze H2 O2 generating more amounts of ·OH under light irradiation once Cu2+ is reduced to Cu+ by glutathione. Such fantastic phenomena confirms that C-m-ABs can act as a photo-Fenton-like agent. Furthermore, C-m-ABs can dramatically accelerate O2 generation (catalase activity) to enhance the PDT of ICG. After loading with the anticancer drug doxorubicin, C-m-ABs are further self-assembled into novel nanobelts, which simultaneously exhibit superior photo-heat conversion effects, enhanced r1 relaxation (21.416 s-1 mm-1 ) and stimuli-responsive drug release behaviors. High cytotoxicity in vitro, effective tumor accumulation capacity observed by fluorescence/photoacoustic/magnetic resonance imaging, and enhanced chemo-/photodynamic/photothermal therapeutic performance are achieved. Based on these results, a photo-Fenton-like metal-protein self-assemblies demonstrate great potential for tumor theranostics.


Assuntos
Cobre/química , Proteínas/química , Nanomedicina Teranóstica , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Glutationa/química , Humanos , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Lasers , Camundongos , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Microambiente Tumoral
13.
J Control Release ; 293: 1-9, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30391316

RESUMO

Ultrafine single-chain tadpole polymers (SCTPs), containing an intrachain crosslinked globule and a pH-sensitive linear polymer chain, have been synthesized. Self-assembly of these polymers depends on the linear block length and the pH, at which the polymer is assembled. Although the SCTPs themselves exhibit a size that is consistent with a single-chain species, the self-assembled SCTPs were found to be substantially larger. Since the transition between these two structures is reversibly dependent on pH, we explored the possibility of utilizing these assemblies to achieve deep tissue penetration in tumors. Our results indicate that there is indeed a pH-dependent deep tissue penetration in ex vivo tumor multicellular spheroids. Moreover, the multi-tadpole assemblies (MTAs) can stably encapsulate hydrophobic molecules, which have been used to encapsulate paclitaxel (PTX). These PTX/MTAs show excellent therapeutic efficacy and biosafety in 4 T1 xenograft mouse models. The innovative multi-compartment aggregates are able to fulfill structure-related function transitions with the variation of microenvironment, which has potential to extremely enrich the design of sophisticated biological agents.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Paclitaxel/administração & dosagem , Animais , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Liberação Controlada de Fármacos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/tratamento farmacológico , Paclitaxel/química , Polímeros/administração & dosagem
14.
World Neurosurg ; 121: e154-e158, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30244073

RESUMO

OBJECTIVE: To estimate the association of different etiologies of cardioembolism (CE), intracranial arterial stenosis (ICAS), or the combination of these conditions with outcomes of mechanical thrombectomy in acute ischemic stroke. METHODS: Data from the intervention group of the Endovascular therapy for Acute ischemic Stroke Trial (EAST) were analyzed. In 140 patients, the presence of CE, ICAS, neither CE nor ICAS, or both conditions was assessed. The primary outcome was a favorable outcome at 90 days (modified Rankin Scale score 0-2); secondary outcomes included successful reperfusion (modified Thrombolysis In Cerebral Infarction grade 2b-3), symptomatic intracerebral hemorrhage, and 90-day mortality. RESULTS: Of 140 patients, 47 had neither CE nor ICAS, 35 had ICAS but not CE, 46 had CE but not ICAS, and 12 had both CE and ICAS. The rate of favorable outcome was 67.1% in the no CE and no ICAS group, 74.3% in the ICAS without CE group, 41.3% in the CE without ICAS group, and 33.3% in the CE and ICAS group. The CE and ICAS group had poor outcomes (odds ratio = 0.20 after adjusting for age, sex, and National Institutes of Health Stroke Scale score; 95% confidence interval, 0.04-0.95; P = 0.043). No significant differences were observed in secondary outcomes. CONCLUSIONS: The presence of both CE and ICAS was associated with poor outcome in patients with anterior circulation large-vessel occlusion treated with endovascular thrombectomy. Future studies are warranted to further explore this association.


Assuntos
Embolia/complicações , Cardiopatias/complicações , Arteriosclerose Intracraniana/complicações , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Idoso , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/cirurgia , Revascularização Cerebral/métodos , Constrição Patológica/complicações , Constrição Patológica/cirurgia , Procedimentos Endovasculares/métodos , Feminino , Humanos , Arteriosclerose Intracraniana/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Terapia Trombolítica/métodos , Resultado do Tratamento
15.
Mater Sci Eng C Mater Biol Appl ; 78: 748-755, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28576045

RESUMO

Surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization has been utilized to fabricate high-capacity strong anion-exchange (AEX) membrane for the separation of protein. By means of RAFT polymerization, quaternized poly(3-(methacrylamidomethyl)-pyridine) brushes formed 3-dimensional nanolayers on the surface of porous anodic aluminum oxide (AAO)-silica composite membrane. The surface properties of the membranes were analyzed by SEM, water contact angle, ATR-FTIR, XPS and TGA. To investigate the adsorption performance, the new AEX membranes were applied to recover a model protein, ovalbumin (OVA). High adsorption capacities of 95.8mg/g membranes (static) and 65.3mg/g membranes (dynamic) were obtained at ambient temperature. In the further studies, up to 90% of the adsorbed OVA was efficiently eluted by using phosphate buffer-1M NaCl as elution medium. The successful separation of OVA with high purity from a mixture protein solution was also achieved by using the AEX membranes. The present study demonstrated that under mild reaction condition, RAFT polymerization can be used to fabricate ion-exchange membrane which has many remarkable features, such as high capacity and selectivity, easy elution and so on.


Assuntos
Polieletrólitos/química , Adsorção , Óxido de Alumínio , Polimerização , Dióxido de Silício , Propriedades de Superfície
16.
Ther Clin Risk Manag ; 12: 817-24, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27307742

RESUMO

Triptolide, an active compound extracted from the Chinese herb thunder god vine (Tripterygium wilfordii Hook F.), has potent antitumor activity. Recently, triptolide was found to have protective effects against acute cerebral ischemia/reperfusion (I/R) injury through inhibition of cell apoptosis. However, the regulatory mechanism of the effect remains unclear. We hypothesize that the regulatory mechanisms of triptolide are mediated by nuclear factor κB (NF-κB) and p53-upregulated-modulator-of-apoptosis signal inhibition. To verify this hypothesis, we occluded the middle cerebral artery in male rats to establish focal cerebral I/R model. The rats received triptolide or vehicle at the onset of reperfusion following middle cerebral artery occlusion. At 24 hours after reperfusion, neurological deficits, infarct volume, and cell apoptosis were evaluated. The expression levels of NF-κBp65, PUMA, and caspase-3 were determined by Western blot. Real-time polymerase chain reaction was used to determine the levels of NF-κBp65 mRNA, PUMA mRNA, and caspase-3 mRNA. NF-κB activity was determined by electrophoretic mobility shift assay. Apoptotic cells were detected using terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining. In I/R group, neurological deficit scores, cerebral infarct volume, expression of NF-κBp65, PUMA, caspase-3, NF-κB activity, and TUNEL-positive cells were found to be increased at 24 hours after I/R injury. The I/R/triptolide rats showed significantly better neurological deficit scores, decreased neural apoptosis, and reduced cerebral infarct volume. In addition, the expression of NF-κBp65, PUMA, caspase-3, and NF-κB activity was suppressed in the I/R/triptolide rats. These results indicate that the neuroprotective effects of triptolide during acute cerebral I/R injury are possibly related to the inhibition of apoptosis through suppression of NF-κB/PUMA signaling pathway.

17.
Mater Sci Eng C Mater Biol Appl ; 62: 45-52, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26952396

RESUMO

A methodology to prepare thermo-responsive graft copolymer by using a novel macro-RAFT agent was proposed. The macro-RAFT agent with pendant dithioester (ZC(S)SR) was facilely prepared via the combination of RAFT polymerization and esterification reaction. By means of ZC(S)SR-initiated RAFT polymerization, the thermo-responsive graft copolymer consisting of poly(methyl methacrylate-co-hydroxylethyl methacrylate) (P(MMA-co-HEMA)) backbone and hydrophilic poly(N-isopropylacrylamide) (PNIPAAm) side chains was constructed through the "grafting from" approach. The chemical compositions and molecular weight distributions of the synthesized polymers were respectively characterized by (1)H nuclear magnetic resonance ((1)H NMR) and gel permeation chromatography (GPC). Self-assembly behavior of the amphiphilic graft copolymers (P(MMA-co-HEMA)-g-PNIPAAm) was studied by transmission electron microscopy (TEM), dynamic light scattering (DLS) and spectrofluorimeter. The critical micelle concentration (CMC) value was 0.052 mg mL(-1). These micelles have thermo-responsibility and a low critical solution temperature (LCST) of 33.5°C. Further investigation indicated that the guest molecule release property of these micelles, which can be well described by a first-order kinetic model, was significantly affected by temperature. Besides, the micelles exhibited excellent biocompatibility and cellular uptake property. Hence, these micelles are considered to have potential application in controlled drug delivery.


Assuntos
Portadores de Fármacos/química , Polímeros/química , Resinas Acrílicas/química , Sobrevivência Celular , Cromatografia em Gel , Doxorrubicina/química , Doxorrubicina/metabolismo , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Difusão Dinâmica da Luz , Espectroscopia de Ressonância Magnética , Micelas , Microscopia Eletrônica de Transmissão , Espectrometria de Fluorescência
18.
Stroke Vasc Neurol ; 1(2): 44-51, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28959463

RESUMO

BACKGROUND AND PURPOSE: 5 recent trials have shown the benefit of endovascular treatment for acute ischaemic stroke (AIS) due to large vessel occlusion of the anterior circulation. This study aims to evaluate the safety and efficacy of Solitaire thrombectomy in patients with moderate-to-severe stroke in the Chinese population, which has a high prevalence of intracranial atherosclerosis. METHODS AND ANALYSIS: This multicentre prospective control study will involve 17 stroke centres in China, and plans to recruit 150 patients in the intervention group, and 150 patients in the medical group, in which patients meet enrolment criteria but refuse intervention. Patients with AIS due to large vessel occlusion indicated for treatment with Solitaire stent retriever within 12 hours of symptom onset, and who meet the inclusion and exclusion criteria, will be enrolled in this study. The primary efficacy endpoint is functional independence as defined by a modified Rankin Scale (mRS) score ≤2 at 90 days or by functional improvement as defined by mRS, using shift analysis. The procedural efficacy endpoint is arterial recanalisation of the occluded target vessel measured by a modified Thrombolysis in Cerebral Infarction (mTICI) score equal or superior to 2b right following the use of the study device. The primary safety endpoint is symptomatic intracranial haemorrhage (sICH) within 24±3 hours postprocedure. ETHICS AND DISSEMINATION: The protocol was approved by the Ethics Committee at the coordinating centre and by the local Institutional Review Board of each participating centre. TRIAL REGISTRATION NUMBER: NCT02350283.


Assuntos
Procedimentos Endovasculares , AVC Isquêmico/terapia , Trombectomia , China , Avaliação da Deficiência , Procedimentos Endovasculares/efeitos adversos , Humanos , AVC Isquêmico/diagnóstico , AVC Isquêmico/fisiopatologia , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Recuperação de Função Fisiológica , Trombectomia/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
19.
Alcohol Clin Exp Res ; 39(10): 1908-16, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26343919

RESUMO

BACKGROUND: Chronic alcohol consumption is a critical contributing factor to ischemic stroke, as it enhances ischemia-induced glutamate release, leading to more severe excitotoxicity and brain damage. But the neural mechanisms underlying this phenomenon are poorly understood. METHODS: We evaluated the effects of chronic alcohol exposure on the modulation of ischemia-induced glutamate release via CB1 and CB2 cannabinoid receptors during middle cerebral artery occlusion, using in vivo microdialysis coupled with high-performance liquid chromatography, in alcohol-naïve rats or rats after 1 or 30 days of withdrawal from chronic ethanol intake (6% v/v for 14 days). RESULTS: Intra-dorsal hippocampus (DH) infusions of ACEA or JWH133, selective CB1 or CB2 receptor agonists, respectively, decreased glutamate release in the DH in alcohol-naïve rats in a dose-dependent manner. Such an effect was reversed by co-infusions of SR141716A or AM630, selective CB1 or CB2 receptor antagonists, respectively. After 30 days, but not 1 day of withdrawal, ischemia induced an enhancement in glutamate release in the DH, as compared with non-alcohol-treated control group. Intra-DH infusions of JWH133, but not ACEA, inhibited ischemia-induced glutamate release in the DH after 30 days of withdrawal. Finally, 1 day of withdrawal did not alter the protein level of CB1 or CB2 receptors in the DH, as compared to non-alcohol-treated control rats. Whereas 30 days of withdrawal robustly decreased the protein level of CB1 receptors, but failed to alter the protein level of CB2 receptors, in the DH, as compared to non-alcohol-treated control rats. CONCLUSIONS: Together, these findings suggest that loss of expression/function of CB1 receptors, but not CB2 receptors in the DH, is correlated with the enhancement of ischemia-induced glutamate release after prolonged alcohol withdrawal.


Assuntos
Etanol/administração & dosagem , Etanol/farmacologia , Ácido Glutâmico/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Isquemia/metabolismo , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Animais , Ácidos Araquidônicos/farmacologia , Canabinoides/antagonistas & inibidores , Canabinoides/farmacologia , Relação Dose-Resposta a Droga , Indóis/farmacologia , Infarto da Artéria Cerebral Média , Masculino , Piperidinas/farmacologia , Pirazóis/farmacologia , Ratos , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/antagonistas & inibidores , Rimonabanto
20.
Chem Commun (Camb) ; 51(8): 1425-8, 2015 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-25493290

RESUMO

Reagent-free synthetic methods are of great interest because of their simplicity and implications in green chemistry. We have taken advantage of photoinduced heterodisulfide metathesis to generate crosslinked polymer nanoparticles. The method of development and the mechanistic basis for the synthetic approach are outlined in this communication.


Assuntos
Dissulfetos/química , Nanopartículas/química , Polímeros/química , Dissulfetos/efeitos da radiação , Processos Fotoquímicos , Raios Ultravioleta
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