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Intracranial arterial dolichoectasia (IADE) is associated with the interaction of hypertension and inflammation, and microcurrent can be effective in hypertension. Therefore, this study aimed to investigate the therapeutic effect of microcurrent electrical stimulation in a mouse IADE model. This study randomly categorized 20 mice into five groups: group 1-C (healthy control), group 2-D (IADE model), group 3-M + D (microcurrent administration before nephrectomy and until brain surgery), group 4-D + M (microcurrent administration for 4 weeks following brain surgery), and group 5-M (microcurrent administration for 4 weeks). Cerebral artery diameter and thickness and cerebral arterial wall extracellular matrix components were assessed. Among the five groups, group 2-D showed significantly higher cerebral arterial wall diameter (117.79 ± 17.05 µm) and proportion of collagen (42.46 ± 14.12%) and significantly lower arterial wall thickness (9.31 ± 2.26 µm) and proportion of smooth muscle cell (SMC) and elastin in the cerebral arterial wall (SMC: 38.05 ± 10.32%, elastin: 11.11 ± 6.97%). Additionally, group 4-D + M exhibited a non-significantly lower diameter (100.28 ± 25.99 µm) and higher thickness (12.82 ± 5.17 µm). Group 5-M demonstrated no evidence of toxicity in the liver and brain. The pilot study revealed that microcurrent is effective in preventing IADE development, although these beneficial effects warrant further investigation.
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Artérias Cerebrais , Hipertensão , Animais , Camundongos , Projetos Piloto , Encéfalo , ElastinaRESUMO
Alzheimer's disease (AD) is one of the most prevalent neurodegenerative diseases and a major contributor to dementia. Although the cause of this condition has been identified long ago as aberrant aggregations of amyloid and tau proteins, effective therapies for it remain elusive. The complexities of drug development for AD treatment are often compounded by the impermeable blood-brain barrier and low-yield brain delivery. In addition, the use of high drug concentrations to overcome this challenge may entail side effects. To address these challenges and enhance the precision of delivery into brain regions affected by amyloid aggregation, we proposed a transferrin-conjugated nanoparticle-based drug delivery system. The transferrin-conjugated melittin-loaded L-arginine-coated iron oxide nanoparticles (Tf-MeLioNs) developed in this study successfully mitigated melittin-induced cytotoxicity and hemolysis in the cell culture system. In the 5XFAD mouse brain, Tf-MeLioNs remarkably reduced amyloid plaque accumulation, particularly in the hippocampus. This study suggested Tf-LioNs as a potential drug delivery platform and Tf-MeLioNs as a candidate for therapeutic drug targeting of amyloid plaques in AD. These findings provide a foundation for further exploration and advancement in AD therapeutics.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Camundongos , Animais , Peptídeos beta-Amiloides/metabolismo , Meliteno/farmacologia , Transferrina/metabolismo , Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Amiloide/metabolismo , Nanopartículas Magnéticas de Óxido de Ferro , Camundongos Transgênicos , Placa Amiloide/metabolismo , Modelos Animais de DoençasRESUMO
Predicting the unseen arterial course and branching pattern distal to vessel occlusion is crucial for endovascular thrombectomy in acute stroke patients. We investigated whether a comprehensive interpretation of NCT and CTA would enhance arterial course prediction more than either NCT or CTA interpretation alone. Among 150 patients who achieved post-thrombectomy TICI grades ≥ IIb for anterior circulation occlusions, we assessed visualization grade on both NCT and CTA by five scales at the thrombosed and the distal-to-thrombus segment, using DSA as the reference standard. The visualization grades were compared and related to various subgroups. The mean visualization grade of the distal-to-thrombus segment on NCT was significantly larger than that of CTA (mean ± SD, 3.62 ± 0.87 versus 3.31 ± 1.20; p < 0.05). On CTA, visualization grade of distal-to-thrombus segment in the good collateral flow subgroup was higher than that in the poor collateral flow subgroup (mean ± SD, 4.01 ± 0.93 versus 2.56 ± 0.99; p < 0.001). After the comprehensive interpretation of NCT and CTA, seventeen cases (11%) showed visualization grade of distal-to-thrombus segment upgrading. Tracing arterial course and piecing branching patterns together in distal-to-occlusion of stroke patients was feasible on the routine pre-interventional NCT and CTA, which may provide timely guidance during thrombectomy.
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Serine protease is linked to a wide range of diseases, prompting the development of robust, selective, and sensitive protease assays and sensing methods. However, the clinical needs for serine protease activity imaging have not yet been met, and the efficient in vivo detection and imaging of serine protease remain challenging. Here, we report the development of the gadolinium-cyclic 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid-click-Sulfonyl Fluoride (Gd-DOTA-click-SF) MRI contrast agent targeting serine protease. The HR-FAB mass spectrum confirmed the successful formation of our designed chelate. The molar longitudinal relaxivity (r1) of the Gd-DOTA-click-SF probe (r1 = 6.82 mM-1 s-1) was significantly higher than that of Dotarem (r1 = 4.63 mM-1 s-1), in the range of 0.01-0.64 mM at 9.4 T. The in vitro cellular study and the transmetallation kinetics study showed that the safety and stability of this probe are comparable to those of conventional Dotarem. Ex vivo abdominal aortic aneurysm (AAA) MRI revealed that this probe has a contrast-agent-to-noise ratio (CNR) that is approximately 51 ± 23 times greater than that of Dotarem. This study of superior visualization of AAA suggests that it has the potential to detect elastase in vivo and supports the feasibility of probing serine protease activity in T1-weighted MRI.
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Meios de Contraste , Gadolínio , Imageamento por Ressonância Magnética/métodos , Serina ProteasesRESUMO
BACKGROUND: Synthetic MRI is a time-efficient imaging technique that provides both quantitative MRI and contrast-weighted images simultaneously. However, a rather long single scan time can be challenging for children. OBJECTIVE: To evaluate the clinical feasibility of time-saving synthetic MRI protocols adjusted for echo train length and receiver bandwidth in pediatric neuroimaging based on image quality assessment and quantitative data analysis. MATERIALS AND METHODS: In total, we included 33 children ages 1.6-17.4 years who underwent synthetic MRI using three sets of echo train length and receiver bandwidth combinations (echo train length [E]12-bandwidth [B in KHz]22, E16-B22 and E16-B83) at 3 T. The image quality and lesion conspicuity of synthetic contrast-weighted images were compared between the suggested protocol (E12-B22) and adjusted protocols (E16-B22 and E16-B83). We also compared tissue values (T1, T2, proton-density values) and brain volumetry. RESULTS: For the E16-B83 combination, image quality was sufficient except for 15.2% of T1-W and 3% of T2-W fluid-attenuated inversion recovery (FLAIR) images, with remarkable scan time reduction (up to 35%). The E16-B22 combination demonstrated a comparable image quality to E12-B22 (P>0.05) with a scan time reduction of up to 8%. There were no significant differences in lesion conspicuity among the three protocols (P>0.05). Tissue value measurements and brain tissue volumes obtained with the E12-B22 protocol and adjusted protocols showed excellent agreement and strong correlations except for gray matter volume and non-white matter/gray matter/cerebrospinal fluid volume in E12-B22 vs. E16-B83. CONCLUSION: The adjusted synthetic protocols produced image quality sufficient or comparable to that of the suggested protocol while maintaining lesion conspicuity with reduced scan time. The quantitative values were generally consistent with the suggested MRI-protocol-derived values, which supports the clinical application of adjusted protocols in pediatric neuroimaging.
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Imageamento por Ressonância Magnética , Neuroimagem , Humanos , Criança , Lactente , Pré-Escolar , Adolescente , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Encéfalo/diagnóstico por imagem , Cabeça , Projetos de PesquisaRESUMO
We report a case of delayed rupture of an anterior communicating artery (Acom) pseudoaneurysm following mechanical thrombectomy (MT) of a distal artery occlusion using a stent retriever. An elderly patient with right hemiparesis showed left proximal internal cerebral artery and middle cerebral artery occlusions. During MT, a fragmented thrombus moved to the anterior cerebral artery (ACA). A stent retriever was deployed to the occluded ACA, and the Acom and proximal ACA segment were significantly straightened. Additionally, we attempted a blind exchange mini-pinning (BEMP) technique, but a subarachnoid hemorrhage (SAH) occurred. Bleeding was almost entirely absorbed 9 days after the procedure, but the SAH recurred at 20 days, and computed tomography angiography revealed a new pseudoaneurysm formation in the Acom. We suggest that the proposed mechanism of pseudoaneurysm formation was likely due to the dislocation and avulsion of the Acom perforators when the ipsilateral ACA was pushed and pulled during MT.
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OBJECTIVE: This study aimed to explore the myelin volume change in patients with mild traumatic brain injury (mTBI) with post-concussion syndrome (PCS) using a multidynamic multiecho (MDME) sequence and automatic whole-brain segmentation. MATERIALS AND METHODS: Forty-one consecutive mTBI patients with PCS and 29 controls, who had undergone MRI including the MDME sequence between October 2016 and April 2018, were included. Myelin volume fraction (MVF) maps were derived from the MDME sequence. After three dimensional T1-based brain segmentation, the average MVF was analyzed at the bilateral cerebral white matter (WM), bilateral cerebral gray matter (GM), corpus callosum, and brainstem. The Mann-Whitney U-test was performed to compare MVF and myelin volume between patients with mTBI and controls. Myelin volume was correlated with neuropsychological test scores using the Spearman rank correlation test. RESULTS: The average MVF at the bilateral cerebral WM was lower in mTBI patients with PCS (median [interquartile range], 25.2% [22.6%-26.4%]) than that in controls (26.8% [25.6%-27.8%]) (p = 0.004). The region-of-interest myelin volume was lower in mTBI patients with PCS than that in controls at the corpus callosum (1.87 cm3 [1.70-2.05 cm3] vs. 2.21 cm3 [1.86-3.46 cm3]; p = 0.003) and brainstem (9.98 cm3 [9.45-11.00 cm3] vs. 11.05 cm3 [10.10-11.53 cm3]; p = 0.015). The total myelin volume was lower in mTBI patients with PCS than that in controls at the corpus callosum (0.45 cm3 [0.39-0.48 cm3] vs. 0.48 cm3 [0.45-0.54 cm3]; p = 0.004) and brainstem (1.45 cm3 [1.28-1.59 cm3] vs. 1.54 cm3 [1.42-1.67 cm3]; p = 0.042). No significant correlation was observed between myelin volume parameters and neuropsychological test scores, except for the total myelin volume at the bilateral cerebral WM and verbal learning test (delayed recall) (r = 0.425; p = 0.048). CONCLUSION: MVF quantified from the MDME sequence was decreased at the bilateral cerebral WM in mTBI patients with PCS. The total myelin volumes at the corpus callosum and brainstem were decreased in mTBI patients with PCS due to atrophic changes.
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Concussão Encefálica , Síndrome Pós-Concussão , Encéfalo , Humanos , Imageamento por Ressonância Magnética/métodos , Bainha de MielinaRESUMO
Considering the crosstalk between the flow and vessel wall, hemodynamic assessment of the neurovascular system may offer a well-integrated solution for both diagnosis and management by adding prognostic significance to the standard CT/MR angiography. 4D flow MRI or time-resolved 3D velocity-encoded phase-contrast MRI has long been promising for the hemodynamic evaluation of the great vessels, but challenged in clinical studies for assessing intracranial vessels with small diameter due to long scan times and low spatiotemporal resolution. Current accelerated MRI techniques, including parallel imaging with compressed sensing and radial k-space undersampling acquisitions, have decreased scan times dramatically while preserving spatial resolution. 4D flow MRI visualized and measured 3D complex flow of neurovascular diseases such as aneurysm, arteriovenous shunts, and atherosclerotic stenosis using parameters including flow volume, velocity vector, pressure gradients, and wall shear stress. In addition to the noninvasiveness of the phase contrast technique and retrospective flow measurement through the wanted windows of the analysis plane, 4D flow MRI has shown several advantages over Doppler ultrasound or computational fluid dynamics. The evaluation of the flow status and vessel wall can be performed simultaneously in the same imaging modality. This article is an overview of the recent advances in neurovascular 4D flow MRI techniques and their potential clinical applications in neurovascular disease. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY STAGE: 3.
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Aneurisma , Imageamento por Ressonância Magnética , Velocidade do Fluxo Sanguíneo , Hemodinâmica , Humanos , Hidrodinâmica , Imageamento Tridimensional , Estudos RetrospectivosRESUMO
Rationale: In intracranial arterial dolichoectasia (IADE) development, the feedback loop between inflammatory cytokines and macrophages involves TNF-α and NF-κB signaling pathways and leads to subsequent MMP-9 activation and extracellular matrix (ECM) degeneration. In this proof-of-concept study, melittin-loaded L-arginine-coated iron oxide nanoparticle (MeLioN) was proposed as the protective measure of IADE formation for this macrophage-mediated inflammation and ECM degeneration. Methods: IADE was created in 8-week-old C57BL/6J male mice by inducing hypertension and elastase injection into a basal cistern. Melittin was loaded on the surface of ION as a core-shell structure (hydrodynamic size, 202.4 nm; polydispersity index, 0.158). Treatment of MeLioN (2.5 mg/kg, five doses) started after the IADE induction, and the brain was harvested in the third week. In the healthy control, disease control, and MeLioN-treated group, the morphologic changes of the cerebral arterial wall were measured by diameter, thickness, and ECM composition. The expression level of MMP-9, CD68, MCP-1, TNF-α, and NF-κB was assessed from immunohistochemistry, polymerase chain reaction, and Western blot assay. Results: MeLioN prevented morphologic changes of cerebral arterial wall related to IADE formation by restoring ECM alterations and suppressing MMP-9 expression. MeLioN inhibited MCP-1 expression and reduced CD68-positive macrophage recruitments into cerebral arterial walls. MeLioN blocked TNF-α activation and NF-κB signaling pathway. In the Sylvian cistern, co-localization was found between the CD68-positive macrophage infiltrations and the MeLioN distributions detected on Prussian Blue and T2* gradient-echo MRI, suggesting the role of macrophage harboring MeLioN. Conclusions: The macrophage infiltration into the arterial wall plays a critical role in the MMP-9 secretion. MeLioN, designed for ION-mediated melittin delivery, effectively prevents IADE formation by suppressing macrophage-mediated inflammations and MMP activity. MeLioN can be a promising strategy preventing IADE development in high-risk populations.
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Artérias Cerebrais/patologia , Transtornos Cerebrovasculares/prevenção & controle , Inflamação/prevenção & controle , Macrófagos/fisiologia , Nanopartículas de Magnetita/uso terapêutico , Meliteno/administração & dosagem , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Transtornos Cerebrovasculares/patologia , Quimiocina CCL2/antagonistas & inibidores , Quimiocina CCL2/metabolismo , Modelos Animais de Doenças , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The aim of this study was to compare the performance of a deep-learning convolutional neural network (Faster R-CNN) model to detect imaging findings suggestive of idiopathic Parkinson's disease (PD) based on [18F]FP-CIT PET maximum intensity projection (MIP) images versus that of nuclear medicine (NM) physicians. The anteroposterior MIP images of the [18F]FP-CIT PET scan of 527 patients were classified as having PD (139 images) or non-PD (388 images) patterns according to the final diagnosis. Non-PD patterns were classified as overall-normal (ONL, 365 images) and vascular parkinsonism with definite defects or prominently decreased dopamine transporter binding (dVP, 23 images) patterns. Faster R-CNN was trained on 120 PD, 320 ONL, and 16 dVP pattern images and tested on the 19 PD, 45 ONL, and seven dVP patterns images. The performance of the Faster R-CNN and three NM physicians was assessed using receiver operating characteristics curve analysis. The difference in performance was assessed using Cochran's Q test, and the inter-rater reliability was calculated. Faster R-CNN showed high accuracy in differentiating PD from non-PD patterns and also from dVP patterns, with results comparable to those of NM physicians. There were no significant differences in the area under the curve and performance. The inter-rater reliability among Faster R-CNN and NM physicians showed substantial to almost perfect agreement. The deep-learning model accurately differentiated PD from non-PD patterns on MIP images of [18F]FP-CIT PET, and its performance was comparable to that of NM physicians.
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Hyperlipidemia is a chronic disorder that plays an important role in the development of cardiovascular diseases, type II diabetes, atherosclerosis, hypertension, and non-alcoholic fatty liver disease. Hyperlipidemias have created a worldwide health crisis and impose a substantial burden not only on personal health but also on societies and economies. Transcription factors in the sterol regulatory element binding protein (SREBP) family are key regulators of the lipogenic genes in the liver. SREBPs regulate lipid homeostasis by controlling the expression of a range of enzymes required for the synthesis of endogenous cholesterol, fatty acids, triacylglycerol, and phospholipids. Thereby, SREBPs have been considered as targets for the treatment of metabolic diseases. The aim of this study was to investigate the beneficial functions and the possible underlying molecular mechanisms of SREBP decoy ODN, which is a novel inhibitor of SREBPs, in high-fat diet (HFD)-fed hyperlipidemic mice. Our studies using HFD-induced hyperlipidemia animal model revealed that SREBB decoy ODN inhibited the increased expression of fatty acid synthetic pathway, such as SREBP-1c, FAS, SCD-1, ACC1, and HMGCR. In addition, SREBP decoy ODN decreased pro-inflammatory cytokines, including TNF-α, IL-1ß, IL-8, and IL-6 expression. These results suggest that SREBP decoy ODN exerts its anti-hyperlipidemia effects in HFD-induced hyperlipidemia mice by regulating their lipid metabolism and inhibiting lipogenesis through inactivation of the SREPB pathway.
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Modelos Animais de Doenças , Hiperlipidemias/prevenção & controle , Oligodesoxirribonucleotídeos/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 1/antagonistas & inibidores , Animais , Vias Biossintéticas/efeitos dos fármacos , Vias Biossintéticas/genética , Citocinas/genética , Citocinas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Hiperlipidemias/etiologia , Hiperlipidemias/genética , Mediadores da Inflamação/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Metabolismo dos Lipídeos/genética , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Masculino , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismoRESUMO
The aim of this study was to analyze the characteristics of time-velocity curve acquired by phase-contrast magnetic resonance imaging (PC-MRI) using an in-vitro flow model as a reference for hemodynamic studies. The time- velocity curves of the PC-MRI were compared with Doppler ultrasonography (US) and also compared with those obtained in the electromagnetic flowmeter. The correlation between techniques was analyzed using an electromagnetic flowmeter as a reference standard; the maximum, minimum, and average velocities, full-width at half-maximum (FWHM), and ascending gradient (AG) were measured from time-velocity curves. The correlations between an electromagnetic flowmeter and the respective measurement technique for the PC-MRI and Doppler US were found to be high (mean R2 > 0.9, p < 0.05). These results indicate that these measurement techniques are useful for measuring blood flow information and reflect actual flow. The PC-MRI was the best fit for the minimum velocity and FWHM, and the maximum velocity and AG were the best fit for Doppler US. The PC-MRI showed lower maximum velocity value and higher minimum velocity value than Doppler US. Therefore, PC-MRI demonstrates more obtuse time-velocity curve than Doppler US. In addition, the time- velocity curve of PC-MRI could be calibrated by introducing formulae that can convert each measurement value to a reference standard value within a 10% error. The PC-MRI can be used to estimate the Doppler US using this formula.
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Velocidade do Fluxo Sanguíneo , Imageamento por Ressonância Magnética/métodos , Hemodinâmica , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Fluxo Pulsátil , Ultrassonografia DopplerRESUMO
OBJECTIVES: To investigate the safety and tolerability of gadobutrol at the recommended dose in patients requiring contrast-enhanced magnetic resonance imaging/angiography (MRI/MRA) in the routine setting. METHODS: GARDIAN prospectively enrolled 23,708 patients undergoing routine gadobutrol-enhanced MRI/MRA for approved indications at 272 study centres in Europe, Asia, North America, and Africa and monitored for adverse events. RESULTS: Median gadobutrol dose was 0.11 mmol/kg body weight. The overall incidence of adverse drug reactions (ADRs) was 0.7 % (n = 170 patients), with similar incidences in patients with renal impairment or cardiac disease, from different geographic regions and in different gadobutrol dose groups. Patients at risk for contrast media reaction had an ADR incidence of 2.5 %. Five patients (0.02 %) experienced serious adverse events, four were drug-related. One patient experienced a fatal anaphylactoid shock, assessed to be related to injection of gadobutrol. The contrast quality of gadobutrol-enhanced images was rated by treating physicians as good or excellent in 97 % cases, with similar ratings in all patient subgroups and indications. CONCLUSIONS: The GARDIAN study shows that gadobutrol at the recommended dose is well tolerated across a large, diverse patient population. KEY POINTS: ⢠Gadobutrol at recommended dose shows low rates of adverse drug reactions ⢠Gadobutrol demonstrates a uniform safety profile across diverse patient groups ⢠Gadobutrol provides excellent contrast quality in routine practice.
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Meios de Contraste/efeitos adversos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética , Compostos Organometálicos/efeitos adversos , Adolescente , Adulto , África , Idoso , Idoso de 80 Anos ou mais , Ásia , Criança , Pré-Escolar , Europa (Continente) , Feminino , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , América do Norte , Estudos Prospectivos , Adulto JovemRESUMO
BACKGROUND AND PURPOSE: The signal information per voxels of magnetic resonance imaging (MRI) for vessel wall could reflect the pathologic features of atherosclerotic vessels. The aim of this study is to evaluate the usefulness of magnetic resonance voxel-based histogram (VBH) of atherosclerotic basilar artery in patients with isolated pontine infarctions (PIs). MATERIALS AND METHODS: Wall and lumen of basilar artery were segmented from high resolution MR of 42 patients with isolated PI and 10 normal volunteers. VBHs were obtained after normalization by dividing the intensity of segmented wall with the intensity of non-infarcted area of pons. The variables of VBH included area (A), mean signal intensity (SI), standard deviation (SD), kurtosis (K), and skewness (SK) and area stenosis [AS; Awall/(Awall + Alumen)] were compared according to the MRI-modified American Heart Association (AHA) atherosclerotic plaque schema, and between the subgroups of PI (lacunar: LPI and paramedian: PPI). RESULTS: According to the MRI-modified AHA atherosclerotic plaque schema, Awall/T1 (mean area of wall on T1-weighted MRI), SIwall/T1, SDwall/T1, SKwall/T1, Kwall/T1, Alumen/T1, and AST1 showed statistical differences. AHA IV-VII showed higher Awall/T1, SIwall/T1, and AST1 than normal control. PPI showed statistical differences in Awall/T1, SIwall/T1, SK wall/T1, and Awall/T2 than those of normal control after post hoc test, whereas LPI in Awall/T1 and Awall/T2 (P < 0.05, Kruskal-Wallis test, Dunnett T3 procedure). CONCLUSIONS: VBH analysis can provide the quantitative information with regard to volume as well as composition of the atherosclerotic plaque in the basilar artery. The difference in patterns of VBH might be further useful in characterizing PIs with presumably different pathogenesis.
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Artéria Basilar/diagnóstico por imagem , Infarto Encefálico/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Placa Aterosclerótica/diagnóstico por imagem , Ponte/irrigação sanguínea , Idoso , Idoso de 80 Anos ou mais , Doenças Cerebelares/diagnóstico por imagem , Constrição Patológica/diagnóstico por imagem , Complicações do Diabetes , Feminino , Humanos , Hipertensão/complicações , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Ponte/diagnóstico por imagem , Fumar , Estados UnidosRESUMO
Atherosclerosis is a complex disease which involves both genetic and environmental factors in its development and progression. Shear stress is the drag force per unit area acting on the endothelium as a result of blood flow, and it plays a critical role in plaque location and progression. TGF-ß1 is often regarded to have pro-atherosclerotic effect on vascular disease. TGF-ß1 downstream targets Smad, for regulating a set of genes associated with atherosclerosis. Therefore, modulation of TGF-ß1 and Smad expression may be the important targets for the prevention and treatment of shear stress-induced vascular disease. However, the precise mechanism of the anti-atherosclerotic effects of novel therapeutic approach has not been elucidated by using animal models regarding the shear stress-induced vascular disease. Therefore, we designed to test whether Smad decoy ODN would prevent the development of atherosclerosis in the shear stress-induced ApoE-/-mice on a western diet. We examined the effect of cast placement on the development of atherosclerosis, and the carotid artery was harvested at the sacrifice to observe histological changes. Also, we evaluated the impact of Smad decoy ODN in the regulation of genes expression related to atherosclerosis, including TGF-ß1, PAI-1, and α-SMA. Our results showed that western diet with cast placement developed atherosclerosis in ApoE-/-mouse. Also, administration of Smad decoy ODN decreases the expression of TGF-ß1, PAI-1, and α-SMA. These results demonstrate the potential of Smad decoy ODN to prevent the progression of atherosclerosis in ApoE-/-mouse model with western diet and shear stress.
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Apolipoproteínas E/genética , Aterosclerose/genética , Placa Aterosclerótica/metabolismo , Proteínas Smad/genética , Animais , Apolipoproteínas E/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Dieta , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Oligodesoxirribonucleotídeos , Placa Aterosclerótica/genética , Placa Aterosclerótica/patologia , Proteínas Smad/metabolismo , Estresse Mecânico , Fator de Crescimento Transformador beta1/metabolismoRESUMO
Atherosclerosis arises when injury to the arterial wall induces an inflammatory cascade that is sustained by a complex network of cytokines, together with accumulation of lipids and fibrous material. Inflammatory cascades involve leukocyte adherence and chemotaxis, which are coordinated by the local secretion of adhesion molecules, chemotactic factors, and cytokines. Transcription factors are critical to the integration of the various steps of the cascade response to mediators of vascular injury, and are induced in a stimulus-dependent and cell-type-specific manner. Several small-nucleic-acid-based therapeutic strategies have recently been developed to target transcription factors: antisense oligodeoxynucleotides, RNA interference, microRNA, and decoy oligodeoxynucleotides. The aim of this review was to provide an overview of these particular targeted therapeutic strategies, toward regulation of the vascular inflammation, remodeling and fibrosis associated with atherosclerosis.
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Aterosclerose/terapia , Inflamação/terapia , MicroRNAs/uso terapêutico , Oligodesoxirribonucleotídeos/uso terapêutico , Oligonucleotídeos Antissenso/uso terapêutico , RNA Interferente Pequeno/uso terapêutico , Fatores de Transcrição/genética , Animais , Aterosclerose/complicações , Aterosclerose/genética , Fibrose , Regulação da Expressão Gênica , Terapia Genética/métodos , Humanos , Inflamação/complicações , Inflamação/genética , MicroRNAs/genética , RNA Interferente Pequeno/genética , Doenças Vasculares/complicações , Doenças Vasculares/genética , Doenças Vasculares/terapiaAssuntos
Falso Aneurisma/diagnóstico , Falso Aneurisma/fisiopatologia , Velocidade do Fluxo Sanguíneo/fisiologia , Lesões das Artérias Carótidas/diagnóstico , Lesões das Artérias Carótidas/fisiopatologia , Artéria Carótida Interna/fisiopatologia , Fístula Carótido-Cavernosa/diagnóstico , Fístula Carótido-Cavernosa/fisiopatologia , Seio Cavernoso/lesões , Seio Cavernoso/fisiopatologia , Angiografia Cerebral/métodos , Traumatismos Cranianos Fechados/diagnóstico , Traumatismos Cranianos Fechados/fisiopatologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Adulto , Volume Sanguíneo/fisiologia , Seguimentos , Humanos , Masculino , Traumatismo Múltiplo/diagnóstico , Traumatismo Múltiplo/fisiopatologia , Remissão EspontâneaRESUMO
Stem cell therapy is currently being studied with a view to rescuing various neurological diseases. Such studies require not only the discovery of potent candidate cells but also the development of methods that allow optimal delivery of those candidates to the brain tissues. Given that the blood-brain barrier (BBB) precludes cells from entering the brain, the present study was designed to test whether hyperosmolar mannitol securely opens the BBB and enhances intra-arterial cell delivery. A noninjured normal canine model in which the BBB was presumed to be closed was used to evaluate the feasibility and safety of the tested protocol. Autologous adipose tissue-derived pericytes with platelet-derived growth factor receptor ß positivity were utilized. Cells were administered 5 min after mannitol pretreatment using one of following techniques: (1) bolus injection of a concentrated suspension, (2) continuous infusion of a diluted suspension, or (3) bolus injection of a concentrated suspension that had been shaken by repeated syringe pumping. Animals administered a concentrated cell suspension without mannitol pretreatment served as a control group. Vital signs, blood parameters, neurologic status, and major artery patency were kept stable throughout the experiment and the 1-month posttreatment period. Although ischemic lesions were noted on magnetic resonance imaging in several mongrel dogs with concentrated cell suspension, the injection technique using repeated syringe shaking could avert this complication. The cells were detected in both ipsilateral and contralateral cortices and were more frequent at the ipsilateral and frontal locations, whereas very few cells were observed anywhere in the brain when mannitol was not preinjected. These data suggest that intra-arterial cell infusion with mannitol pretreatment is a feasible and safe therapeutic approach in stable brain diseases such as chronic stroke.
Assuntos
Tecido Adiposo/citologia , Barreira Hematoencefálica/efeitos dos fármacos , Manitol/farmacologia , Transplante de Células-Tronco , Células-Tronco/metabolismo , Tecido Adiposo/metabolismo , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cães , Estudos de Viabilidade , Injeções Intra-Arteriais , Imageamento por Ressonância Magnética , Masculino , Modelos Animais , Radiografia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Células-Tronco/citologia , Transplante AutólogoRESUMO
Venous hypertension is closely related to poor outcome of a dural arteriovenous fistula (DAVF). However, no direct measurements have been made of the shunt flow and impaired venous drainage that are suggestive of venous hypertension. We present a case of a 35-year-old man who presented with cerebral hemorrhage and underwent coil embolization for tentorial DAVF. Two-dimensional (2D) phase-contrast magnetic resonance imaging (MRI) was used to evaluate temporal changes in the flow volumes of the shunt and venous drainage between before and after embolization. The results demonstrated the feasibility of using 2D phase-contrast MRI to measure the shunt volume of a DAVF, which might be useful for assessing the improvement in cerebral circulation after embolization treatment.
RESUMO
The cerebral protection device (CPD) itself may cause complications, including locking between the CPD and other devices, that may result in catastrophic outcomes requiring surgical removal of these locked devices. We describe a case of locking between a CPD and the stent-delivering catheter during carotid artery stenting, which was safely rescued by endovascular retrieval. The mechanism underlying locking with the CPD as well as preventive actions and maneuvers for rescuing the situation are discussed.