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1.
Front Endocrinol (Lausanne) ;15: 1357580, 2024.
ArtigoemInglês |MEDLINE | ID: mdl-38706699

RESUMO

Background and objective: Type 2 Diabetes Mellitus (T2DM) with insulin resistance (IR) is prone to damage the vascular endothelial, leading to the formation of vulnerable carotid plaques and increasing ischemic stroke (IS) risk. The purpose of this study is to develop a nomogram model based on carotid ultrasound radiomics for predicting IS risk in T2DM patients. Methods: 198 T2DM patients were enrolled and separated into study and control groups based on IS history. After manually delineating carotid plaque region of interest (ROI) from images, radiomics features were identified and selected using the least absolute shrinkage and selection operator (LASSO) regression to calculate the radiomics score (RS). A combinatorial logistic machine learning model and nomograms were created using RS and clinical features like the triglyceride-glucose index. The three models were assessed using area under curve (AUC) and decision curve analysis (DCA). Results: Patients were divided into the training set and the testing set by the ratio of 0.7. 4 radiomics features were selected. RS and clinical variables were all statically significant in the training set and were used to create a combination model and a prediction nomogram. The combination model (radiomics + clinical nomogram) had the largest AUC in both the training set and the testing set (0.898 and 0.857), and DCA analysis showed that it had a higher overall net benefit compared to the other models. Conclusions: This study created a carotid ultrasound radiomics machine-learning-based IS risk nomogram for T2DM patients with carotid plaques. Its diagnostic performance and clinical prediction capabilities enable accurate, convenient, and customized medical care.


Assuntos
Diabetes Mellitus Tipo 2, AVC Isquêmico, Nomogramas, Ultrassonografia, Humanos, Diabetes Mellitus Tipo 2/complicações, Diabetes Mellitus Tipo 2/diagnóstico por imagem, Masculino, Feminino, Pessoa de Meia-Idade, AVC Isquêmico/diagnóstico por imagem, AVC Isquêmico/etiologia, AVC Isquêmico/epidemiologia, Idoso, Ultrassonografia/métodos, Fatores de Risco, Aprendizado de Máquina, Artérias Carótidas/diagnóstico por imagem, Artérias Carótidas/patologia, Medição de Risco/métodos, Ultrassonografia das Artérias Carótidas, Radiômica
2.
Sci Rep ;14(1): 10092, 2024 05 02.
ArtigoemInglês |MEDLINE | ID: mdl-38698141

RESUMO

Carotid artery webs (CaW) are non-atherosclerotic projections into the vascular lumen and have been linked to up to one-third of cryptogenic strokes in younger patients. Determining how CaW affects local hemodynamics is essential for understanding clot formation and stroke risk. Computational fluid dynamics simulations were used to investigate patient-specific hemodynamics in carotid artery bifurcations with CaW, bifurcations with atherosclerotic lesions having a similar degree of lumen narrowing, and with healthy carotid bifurcations. Simulations were conducted using segmented computed tomography angiography geometries with inlet boundary conditions extracted from 2D phase contrast MRI scans. The study included carotid bifurcations with CaW (n = 13), mild atherosclerosis (n = 7), and healthy bifurcation geometries (n = 6). Hemodynamic parameters associated with vascular dysfunction and clot formation, including shear rate, oscillatory shear index (OSI), low velocity, and flow stasis were calculated and compared between the subject groups. Patients with CaW had significantly larger regions containing low shear rate, high OSI, low velocity, and flow stasis in comparison to subjects with mild atherosclerosis or normal bifurcations. These abnormal hemodynamic metrics in patients with CaW are associated with clot formation and vascular dysfunction and suggest that hemodynamic assessment may be a tool to assess stroke risk in these patients.


Assuntos
Doenças das Artérias Carótidas, Hemodinâmica, Humanos, Masculino, Doenças das Artérias Carótidas/fisiopatologia, Doenças das Artérias Carótidas/diagnóstico por imagem, Feminino, Pessoa de Meia-Idade, Idoso, Artérias Carótidas/diagnóstico por imagem, Artérias Carótidas/fisiopatologia, Angiografia por Tomografia Computadorizada, Trombose/fisiopatologia, Trombose/diagnóstico por imagem, Imageamento por Ressonância Magnética
3.
Physiol Rep ;12(9): e16024, 2024 May.
ArtigoemInglês |MEDLINE | ID: mdl-38697946

RESUMO

We investigated the associations of the measures of arterial health with cognition in adolescents and whether physical activity (PA) or sedentary time (ST) confounds these associations. One hundred sixteen adolescents (71 boys) aged 15.9 ± 0.4 participated in the study. PA and ST were assessed using a combined accelerometer/heart rate monitor. Overall cognition was computed from the results of psychomotor function, attention, working memory, and paired-associate learning tests. Pulse wave velocity was measured by impedance cardiography, carotid intima-media thickness, and carotid artery distensibility by carotid ultrasonography. Systolic and diastolic blood pressure (SBP and DBP) were measured using an aneroid sphygmomanometer. SBP was inversely associated with overall cognition (standardized regression coefficient [ß] = -0.216, 95% confidence interval (CI) -0.406 to -0.027, p = 0.025). Pulse wave velocity (ß = -0.199, 95% CI -0.382 to -0.017, p = 0.033) was inversely associated with working memory task accuracy. SBP was directly associated with reaction time in the attention (ß = 0.256, 95% CI 0.069 to 0.443, p = 0.008) and errors in the paired-associate learning tasks (ß = 0.308, 95% CI 0.126 to 0.489, p = 0.001). Blood pressure was inversely associated with overall cognition. PA or ST did not confound the associations. Results suggest that preventing high blood pressure is important for promoting cognition in adolescents.


Assuntos
Pressão Sanguínea, Cognição, Análise de Onda de Pulso, Humanos, Adolescente, Masculino, Feminino, Cognição/fisiologia, Pressão Sanguínea/fisiologia, Análise de Onda de Pulso/métodos, Memória de Curto Prazo/fisiologia, Comportamento Sedentário, Frequência Cardíaca/fisiologia, Espessura Intima-Media Carotídea, Atenção/fisiologia, Exercício Físico/fisiologia, Artérias Carótidas/diagnóstico por imagem, Artérias Carótidas/fisiologia
4.
Acta Cir Bras ;39: e392524, 2024.
ArtigoemInglês |MEDLINE | ID: mdl-38808818

RESUMO

PURPOSE: To evaluate the use of the latest generation smartphone camera in performing arterial microanastomosis in rats. METHODS: Ten Wistar rats were divided into 2 groups and underwent anastomosis of the right carotid artery with the aid of magnification from a microscope (group M) and a smartphone camera (group S), to compare patency in 72 hours, as well as to measure the weight of the animals, diameter of the carotid arteries and anastomosis time. RESULTS: There was no statistical difference between the weight of the animals or the diameter of the carotid arteries. There was a statistical difference for the time spent on anastomoses, which was greater in group S, with higher rates of thrombosis (p < 0.05). CONCLUSIONS: Although our patency and anastomosis time results were statistically lower in the smartphone group, there was success in some cases. As the segment continues to progress, it is likely that the results will improve in line with the evolution of camera technology.


Assuntos
Anastomose Cirúrgica, Artérias Carótidas, Microscopia, Microcirurgia, Ratos Wistar, Smartphone, Animais, Microcirurgia/instrumentação, Microcirurgia/métodos, Microscopia/instrumentação, Microscopia/métodos, Anastomose Cirúrgica/instrumentação, Anastomose Cirúrgica/métodos, Artérias Carótidas/cirurgia, Masculino, Fatores de Tempo, Grau de Desobstrução Vascular, Ratos, Reprodutibilidade dos Testes
7.
Int J Biol Macromol ;269(Pt 1): 132040, 2024 Jun.
ArtigoemInglês |MEDLINE | ID: mdl-38702003

RESUMO

Decellularized vascular tissue has high potential as a tissue-engineered vascular graft because of its similarity to native vessels in terms of mechanical strength. However, exposed collagen on the tissue induces blood coagulation, and low hemocompatibility is a major obstacle to its vascular application. Here we report that freeze-drying and ethanol treatment effectively modify collagen fiber structure and drastically reduce blood coagulation on the graft surface without exogenous chemical modification. Decellularized carotid artery of ostrich was treated with freeze-drying and ethanol solution at concentrations ranging between 5 and 99.5 %. Collagen fiber distance in the graft was narrowed by freeze-drying, and the non-helical region increased by ethanol treatment. Although in vitro blood coagulation pattern was similar on the grafts, platelet adhesion on the grafts was largely suppressed by freeze-drying and ethanol treatments. Ex vivo blood circulation tests also indicated that the adsorption of platelets and Von Willebrand Factor was largely reduced to approximately 80 % by ethanol treatment. These results indicate that structural modification of collagen fibers in decellularized tissue reduces blood coagulation on the surface by inhibiting platelet adhesion.


Assuntos
Coagulação Sanguínea, Colágeno, Adesividade Plaquetária, Animais, Adesividade Plaquetária/efeitos dos fármacos, Coagulação Sanguínea/efeitos dos fármacos, Colágeno/química, Engenharia Tecidual/métodos, Teste de Materiais, Liofilização, Prótese Vascular, Alicerces Teciduais/química, Plaquetas/metabolismo, Plaquetas/química, Materiais Biocompatíveis/química, Materiais Biocompatíveis/farmacologia, Artérias Carótidas/efeitos dos fármacos, Humanos, Etanol/química
8.
Front Biosci (Landmark Ed) ;29(5): 173, 2024 May 06.
ArtigoemInglês |MEDLINE | ID: mdl-38812305

RESUMO

BACKGROUND: Neointimal hyperplasia (NIH) is the pathological basis of vascular injury disease. Vascular cells are the dominant cells in the process of NIH, but the extent of heterogeneity amongst them is still unclear. METHODS: A mouse model of NIH was constructed by inducing carotid artery ligation. Single-cell sequencing was then used to analyze the transcriptional profile of vascular cells. Cluster features were determined by functional enrichment analysis, gene set scoring, pseudo-time analysis, and cell-cell communication analysis. Additionally, immunofluorescence staining was conducted on vascular tissues from fibroblast lineage-traced (PdgfraDreER-tdTomato) mice to validate the presence of Pecam1+Pdgfra+tdTomato+ cells. RESULTS: The left carotid arteries (ligation) were compared to right carotid arteries (sham) from ligation-induced NIH C57BL/6 mice. Integrative analyses revealed a high level of heterogeneity amongst vascular cells, including fourteen clusters and seven cell types. We focused on three dominant cell types: endothelial cells (ECs), vascular smooth muscle cells (vSMCs), and fibroblasts. The major findings were: (1) four subpopulations of ECs, including ECs4, mesenchymal-like ECs (ECs1 and ECs2), and fibro-like ECs (ECs3); (2) four subpopulations of fibroblasts, including pro-inflammatory Fibs-1, Sca1+ Fibs-2, collagen-producing Fibs-3, and mesenchymal-like Fibs-4; (3) four subpopulations of vSMCs, including vSMCs-1, vSMCs-2, vSMCs-3, and vSMCs-3-derived vSMCs; (4) ECs3 express genes related to extracellular matrix (ECM) remodeling and cell migration, and fibro-like vSMCs showed strong chemokine secretion and relatively high levels of proteases; (5) fibro-like vSMCs that secrete Vegfa interact with ECs mainly through vascular endothelial growth factor receptor 2 (Vegfr2). CONCLUSIONS: This study presents the dynamic cellular landscape within NIH arteries and reveals potential relationships between several clusters, with a specific focus on ECs3 and fibro-like vSMCs. These two subpopulations may represent potential target cells for the treatment of NIH.


Assuntos
Perfilação da Expressão Gênica, Hiperplasia, Camundongos Endogâmicos C57BL, Músculo Liso Vascular, Neointima, Análise de Célula Única, Animais, Neointima/patologia, Neointima/metabolismo, Neointima/genética, Análise de Célula Única/métodos, Hiperplasia/genética, Músculo Liso Vascular/metabolismo, Músculo Liso Vascular/patologia, Músculo Liso Vascular/citologia, Camundongos, Células Endoteliais/metabolismo, Células Endoteliais/patologia, Artérias Carótidas/patologia, Artérias Carótidas/metabolismo, Miócitos de Músculo Liso/metabolismo, Miócitos de Músculo Liso/patologia, Masculino, Fibroblastos/metabolismo, Fibroblastos/patologia, Modelos Animais de Doenças, Análise da Expressão Gênica de Célula Única
9.
Medicina (Kaunas) ;60(5)2024 May 20.
ArtigoemInglês |MEDLINE | ID: mdl-38793019

RESUMO

Background and objective: carotid artery stenosis contributes significantly to ischemic strokes, with management options including carotid endarterectomy (CEA) and carotid artery stenting (CAS) ischemic stroke risk can be reduced. Controversies persist regarding their efficacy and factors influencing complications, and understanding the relationship between atherosclerotic plaque characteristics and stent restenosis after CAS is crucial. Methods: we conducted a retrospective study involving 221 patients who underwent CAS for symptomatic or asymptomatic carotid artery stenosis. Comprehensive assessments of plaque morphology were performed using contrast-enhanced ultrasound (CEUS) before CAS. Patient demographics, including smoking status and diabetes, were also recorded. Stent restenosis was diagnosed using various imaging modalities, including ultrasound, angiography, and digital subtraction angiography (DSA). Results: plaque analysis using CEUS revealed a significant association between plaque grade and restenosis incidence (p < 0.001), particularly with grade 0 (11.1%) and grade 2 plaques (66.7%). Smoking was notably associated with plaque vascularization and restenosis (p < 0.001), while diabetes did not significantly impact plaque characteristics or restenosis risk (p > 0.05). The mean duration of restenosis was 17.67 months. Stenting was the most frequent treatment modality for restenosis (70.6%). However, no significant relationship was found between restenosis type and plaque morphology (p = 0.268). Furthermore, while no clear relationship was observed between plaque morphology and the type of restenosis, our findings underscored the importance of plaque characterization in predicting post-CAS outcomes. Conclusions: this study highlights the utility of CEUS in predicting stent restenosis following CAS. There was a significant association between stent restenosis within 12-24 months after the carotid stenting procedure and an elevated grade of plaque vascularization. Moreover, one of the main factors possibly determining the grade of plaque vascularization was smoking. Further research is warranted to elucidate the underlying mechanisms and refine risk stratification in this patient population.


Assuntos
Estenose das Carótidas, Meios de Contraste, Placa Aterosclerótica, Stents, Ultrassonografia, Humanos, Estudos Retrospectivos, Masculino, Feminino, Idoso, Stents/efeitos adversos, Estenose das Carótidas/cirurgia, Estenose das Carótidas/diagnóstico por imagem, Placa Aterosclerótica/diagnóstico por imagem, Pessoa de Meia-Idade, Ultrassonografia/métodos, Artérias Carótidas/diagnóstico por imagem, Artérias Carótidas/cirurgia, Angiografia Digital/métodos, Idoso de 80 Anos ou mais, Fatores de Risco
10.
Mol Biol Rep ;51(1): 540, 2024 Apr 20.
ArtigoemInglês |MEDLINE | ID: mdl-38642151

RESUMO

BACKGROUND: The MMP-9 is a known player in atherosclerosis, yet associations of the MMP-9 -1562 C/T variant (rs3918242) with various atherosclerotic phenotypes and tissue mRNA expression are still contradictory. This study aimed to investigate the MMP-9 -1562 C/T variant, its mRNA and protein expression in carotid plaque (CP) tissue, as a risk factor for CP presence and as a marker of different plaque phenotypes (hyperechoic and hypoechoic) in patients undergoing carotid endarterectomy. The MnSOD as an MMP-9 negative regulator was also studied in relation to CP phenotypes. METHODS AND RESULTS: Genotyping of 770 participants (285 controls/485 patients) was done by tetra-primer ARMS PCR. The MMP-9 mRNA expression in 88 human CP tissues was detected by TaqMan® technology. The protein levels of MMP-9 and MnSOD were assessed by Western blot analysis. The MMP-9 -1562 C/T variant was not recognized as a risk factor for plaque presence or in predisposing MMP-9 mRNA and protein levels in plaque tissue. Patients with hypoechoic plaques had significantly lower MMP-9 mRNA and protein levels than those with hyperechoic plaque (p = 0.008, p = 0.003, respectively). MnSOD protein level was significantly higher in hypoechoic plaque compared to hyperechoic (p = 0.039). MMP-9 protein expression in CP tissue was significantly affected by sex and plaque type interaction (p = 0.009). CONCLUSIONS: Considering the differences of MMP-9 mRNA and protein expression in CP tissue regarding different plaque phenotypes and the observed sex-specific effect, the role of MMP-9 in human atherosclerotic plaques should be further elucidated.


Assuntos
Aterosclerose, Doenças das Artérias Carótidas, Metaloproteinase 9 da Matriz, Placa Aterosclerótica, Feminino, Humanos, Masculino, Aterosclerose/genética, Artérias Carótidas, Doenças das Artérias Carótidas/genética, Doenças das Artérias Carótidas/metabolismo, Metaloproteinase 9 da Matriz/genética, Metaloproteinase 9 da Matriz/metabolismo, Placa Aterosclerótica/genética, Placa Aterosclerótica/metabolismo, Placa Aterosclerótica/patologia, RNA Mensageiro/genética, RNA Mensageiro/metabolismo
11.
Ultrasonics ;140: 107312, 2024 May.
ArtigoemInglês |MEDLINE | ID: mdl-38599075

RESUMO

BACKGROUND: Shear wave elastography (SWE) is mainly used for stiffness estimation of large, homogeneous tissues, such as the liver and breasts. However, little is known about its accuracy and applicability in thin (∼0.5-2 mm) vessel walls. To identify possible performance differences among vendors, we quantified differences in measured wave velocities obtained by commercial SWE implementations of various vendors over different imaging depths in a vessel-mimicking phantom. For reference, we measured SWE values in the cylindrical inclusions and homogeneous background of a commercial SWE phantom. Additionally, we compared the accuracy between a research implementation and the commercially available clinical SWE on an Aixplorer ultrasound system in phantoms and in vivo in patients. METHODS: SWE measurements were performed over varying depths (0-35 mm) using three ultrasound machines with four ultrasound probes in the homogeneous 20 kPa background and cylindrical targets of 10, 40, and 60 kPa of a multi-purpose phantom (CIRS-040GSE) and in the anterior and posterior wall of a homogeneous polyvinyl alcohol vessel-mimicking phantom. These phantom data, along with in vivo SWE data of carotid arteries in 23 patients with a (prior) head and neck neoplasm, were also acquired in the research and clinical mode of the Aixplorer ultrasound machine. Machine-specific estimated phantom stiffness values (CIRS phantom) or wave velocities (vessel phantom) over all depths were visualized, and the relative error to the reference values and inter-frame variability (interquartile range/median) were calculated. Correlations between SWE values and target/vessel wall depth were explored in phantoms and in vivo using Spearman's correlations. Differences in wave velocities between the anterior and posterior arterial wall were assessed with Wilcoxon signed-rank tests. Intra-class correlation coefficients were calculated for a sample of ten patients as a measure of intra- and interobserver reproducibility of SWE analyses in research and clinical mode. RESULTS: There was a high variability in obtained SWE values among ultrasound machines, probes, and, in some cases, with depth. Compared to the homogeneous CIRS-background, this variation was more pronounced for the inclusions and the vessel-mimicking phantom. Furthermore, higher stiffnesses were generally underestimated. In the vessel-mimicking phantom, anterior wave velocities were (incorrectly) higher than posterior wave velocities (3.4-5.6 m/s versus 2.9-5.9 m/s, p ≤ 0.005 for 3/4 probes) and remarkably correlated with measurement depth for most machines (Spearman's ρ = -0.873-0.969, p < 0.001 for 3/4 probes). In the Aixplorer's research mode, this difference was smaller (3.3-3.9 m/s versus 3.2-3.6 m/s, p = 0.005) and values did not correlate with measurement depth (Spearman's ρ = 0.039-0.659, p ≥ 0.002). In vivo, wave velocities were higher in the posterior than the anterior vessel wall in research (left p = 0.001, right p < 0.001) but not in clinical mode (left: p = 0.114, right: p = 0.483). Yet, wave velocities correlated with vessel wall depth in clinical (Spearman's ρ = 0.574-0.698, p < 0.001) but not in research mode (Spearman's ρ = -0.080-0.466, p ≥ 0.003). CONCLUSIONS: We observed more variation in SWE values among ultrasound machines and probes in tissue with high stiffness and thin-walled geometry than in low stiffness, homogeneous tissue. Together with a depth-correlation in some machines, where carotid arteries have a fixed location, this calls for caution in interpreting SWE results in clinical practice for vascular applications.


Assuntos
Técnicas de Imagem por Elasticidade, Imagens de Fantasmas, Técnicas de Imagem por Elasticidade/métodos, Técnicas de Imagem por Elasticidade/instrumentação, Humanos, Artérias Carótidas/diagnóstico por imagem, Artérias Carótidas/fisiopatologia, Feminino, Masculino, Pessoa de Meia-Idade, Idoso, Reprodutibilidade dos Testes, Neoplasias de Cabeça e Pescoço/diagnóstico por imagem, Desenho de Equipamento, Adulto
12.
J Vis Exp ;(205)2024 Mar 15.
ArtigoemInglês |MEDLINE | ID: mdl-38557500

RESUMO

Given recent advances in the delivery of novel antitumor therapeutics using endovascular selective intraarterial delivery methods in neuro-oncology, there is an urgent need to develop methods for intracarotid injections in mouse models, including methods to repair the carotid artery in mice after injection to allow for subsequent injections. We developed a method of intracarotid injection in a mouse model to deliver therapeutics into the internal carotid artery (ICA) with two alternative procedures. During injection, the needle is inserted into the common carotid artery (CCA) after tying a suture around the external carotid artery (ECA) and injected therapeutics are delivered into the ICA. Following injection, the common carotid artery (CCA) can be ligated, which limits the number of intracarotid injections to one. The alternative procedure described in this article includes a modification where intracarotid artery injection is followed by injection site repair of the CCA, which restores blood flow within the CCA and avoids the complication of cerebral ischemia seen in some mouse models. We also compared the delivery of bone marrow-derived human mesenchymal stem cells (BM-hMSCs) to intracranial tumors when delivered through intracarotid injection with and without injection site repair following the injection. Delivery of BM-hMSCs does not differ significantly between the methods. Our results demonstrate that injection site repair of the CCA allows for repeat injections through the same artery and does not impair the delivery and distribution of injected material, thus providing a model with greater flexibility that more closely emulates intracarotid injection in humans.


Assuntos
Isquemia Encefálica, Neoplasias Encefálicas, Humanos, Camundongos, Animais, Artéria Carótida Interna/cirurgia, Artéria Carótida Primitiva, Artérias Carótidas, Artéria Carótida Externa
13.
EuroIntervention ;20(7): e445-e452, 2024 Apr 01.
ArtigoemInglês |MEDLINE | ID: mdl-38562068

RESUMO

BACKGROUND: Technological and surgical approaches to carotid artery stenting (CAS) have evolved. Modern randomised controlled trials comparing CAS and carotid endarterectomy (CEA) are limited, and information about updated post-intervention outcomes are mostly from retrospective, small studies. AIMS: This study aims to compare the 30-day outcomes of stroke, transient ischaemic attack (TIA), acute myocardial infarction (AMI) and death with propensity-matched groups of CEA and CAS in asymptomatic and symptomatic patients over a recent study period of new CAS technologies and approaches. METHODS: A retrospective, observational, multicentre analysis was conducted including consecutive symptomatic and asymptomatic patients treated with either primary CEA or CAS for internal carotid artery stenosis, between 2015 and 2022. Patients were propensity score-matched based on comorbidities and assessed according to symptom status. Primary endpoints include composite ipsilateral stroke, TIA, AMI and death within 30 days. Secondary endpoints include technical success and length of hospital stay. RESULTS: From a cohort of 1,110 patients, propensity matching produced 269 distinct treatment pairs (n=538). Most patients were asymptomatic (n=456, 85%). All 6 strokes were minor (CEA=2; CAS=4) and registered among asymptomatic patients. One AMI (CEA) and 1 patient death (CAS) were reported among symptomatic patients. Composite stroke/AMI/death were not significantly different between both types of symptom status and both revascularisation techniques (p=0.44 and p=1, respectively). Technical success was 100%. The length of hospital stay was significantly shorter in asymptomatic patients treated with CAS compared to those treated with CEA (p=0.05), but no difference was registered among symptomatic patients (p=0.32). CONCLUSIONS: Propensity-matched analysis suggests that CAS has similar postprocedural outcomes for stroke, AMI and death at 30 days compared to CEA.


Assuntos
Estenose das Carótidas, Endarterectomia das Carótidas, Ataque Isquêmico Transitório, Infarto do Miocárdio, Acidente Vascular Cerebral, Humanos, Endarterectomia das Carótidas/efeitos adversos, Estenose das Carótidas/cirurgia, Ataque Isquêmico Transitório/etiologia, Estudos Retrospectivos, Pontuação de Propensão, Resultado do Tratamento, Stents, Acidente Vascular Cerebral/etiologia, Infarto do Miocárdio/etiologia, Artérias Carótidas, Fatores de Risco
15.
ArtigoemInglês |MEDLINE | ID: mdl-38564354

RESUMO

For high-frame-rate ultrasound imaging, it remains challenging to implement on compact systems as a sparse imaging configuration with limited array channels. One key issue is that the resulting image quality is known to be mediocre not only because unfocused plane-wave excitations are used but also because grating lobes would emerge in sparse-array configurations. In this article, we present the design and use of a new channel recovery framework to infer full-array plane-wave channel datasets for periodically sparse arrays that operate with as few as one-quarter of the full-array aperture. This framework is based on a branched encoder-decoder convolutional neural network (CNN) architecture, which was trained using full-array plane-wave channel data collected from human carotid arteries (59 864 training acquisitions; 5-MHz imaging frequency; 20-MHz sampling rate; plane-wave steering angles between -15° and 15° in 1° increments). Three branched encoder-decoder CNNs were separately trained to recover missing channels after differing degrees of channelwise downsampling (2, 3, and 4 times). The framework's performance was tested on full-array and downsampled plane-wave channel data acquired from an in vitro point target, human carotid arteries, and human brachioradialis muscle. Results show that when inferred full-array plane-wave channel data were used for beamforming, spatial aliasing artifacts in the B-mode images were suppressed for all degrees of channel downsampling. In addition, the image contrast was enhanced compared with B-mode images obtained from beamforming with downsampled channel data. When the recovery framework was implemented on an RTX-2080 GPU, the three investigated degrees of downsampling all achieved the same inference time of 4 ms. Overall, the proposed framework shows promise in enhancing the quality of high-frame-rate ultrasound images generated using a sparse-array imaging setup.


Assuntos
Artérias Carótidas, Processamento de Imagem Assistida por Computador, Redes Neurais de Computação, Ultrassonografia, Humanos, Ultrassonografia/métodos, Processamento de Imagem Assistida por Computador/métodos, Artérias Carótidas/diagnóstico por imagem, Algoritmos
16.
Rev Med Liege ;79(4): 248-254, 2024 Apr.
ArtigoemFrancês |MEDLINE | ID: mdl-38602213

RESUMO

Carotid artery atherosclerosis is one of the leading causes of stroke. Even though the association between the risk of stroke and the level of morphological stenosis of a carotid plaque has been known for a long time, growing evidence has since proven necessary to assess the composition of the plaque itself to identify vulnerability predictors. These vulnerable plaques, even more if non-stenosing, may be responsible for a significant - but hard to quantify - proportion of strokes so far classified cryptogenic. As a matter of fact, plaque composition may escape detection and characterisation with classical imaging. Several biomarkers associated with its vulnerability to destabilization and with the risk of stroke such as intraplaque hemorrhage and inflammation are now routinely assessable. After a few pathophysiological reminders and a critical reading of the historical literature concerning carotid artery atherosclerosis management, we will review in this article the imaging techniques that can be used in the routine work-up of a carotid atherosclerotic plaque, with a focus on vessel wall magnetic resonance imaging and contrast enhanced ultrasonography.


L'athérosclérose carotidienne est une des causes les plus fréquentes d'accident ischémique cérébral (AIC). Si la dangerosité d'une plaque d'athérome est historiquement vue uniquement à travers le prisme de la sténose qu'elle engendre, l'évolution des connaissances nous pousse à considérer sa composition à la recherche de facteurs de vulnérabilité. Ces plaques à risque, a fortiori «non sténosantes¼, sont responsables d'une proportion difficilement quantifiable, mais probablement non négligeable d'AIC jusqu'ici considérés cryptogéniques. En effet, ces critères échappent pour beaucoup aux méthodes d'imagerie traditionnelle. Plusieurs propriétés associées à la vulnérabilité de la plaque et au risque d'AIC, principalement l'hémorragie intra-plaque et l'inflammation, sont désormais accessibles en pratique courante. Après quelques rappels physiopathologiques et une lecture critique de la littérature historique de la prise en charge de l'athérome carotidien, nous passerons en revue les différentes techniques d'imagerie utilisables en routine dans la mise au point de la plaque d'athérosclérose, avec un focus pratique sur l'imagerie pariétale vasculaire par résonance magnétique et, dans une moindre mesure, par échographie de contraste.


Assuntos
Aterosclerose, Doenças das Artérias Carótidas, Estenose das Carótidas, Placa Aterosclerótica, Acidente Vascular Cerebral, Humanos, Estenose das Carótidas/diagnóstico por imagem, Estenose das Carótidas/complicações, Doenças das Artérias Carótidas/diagnóstico por imagem, Doenças das Artérias Carótidas/complicações, Artérias Carótidas/diagnóstico por imagem, Artérias Carótidas/patologia, Acidente Vascular Cerebral/etiologia, Placa Aterosclerótica/diagnóstico por imagem, Placa Aterosclerótica/complicações, Imageamento por Ressonância Magnética/efeitos adversos, Aterosclerose/complicações
17.
J Physiol Sci ;74(1): 24, 2024 Apr 10.
ArtigoemInglês |MEDLINE | ID: mdl-38600445

RESUMO

Actin linked regulatory mechanisms are known to contribute contraction/relaxation in smooth muscle. In order to clarify whether modulation of polymerization/depolymerization of actin filaments affects relaxation process, we examined the effects of cytochalasin D on relaxation process by Ca2+ removal after Ca2+-induced contraction of ß-escin skinned (cell membrane permeabilized) taenia cecum and carotid artery preparations from guinea pigs. Cytochalasin D, an inhibitor of actin polymerization, significantly suppressed the force during relaxation both in skinned taenia cecum and carotid artery. The data fitting analysis of the relaxation processes indicates that cytochalasin D accelerates slow (latch-like) bridge dissociation. Cytochalasin D seems to directly disrupts actin filament organization or its length, resulting in modulation of actin filament structure that prevents myosin binding.


Assuntos
Actinas, Contração Muscular, Cobaias, Animais, Contração Muscular/fisiologia, Actinas/metabolismo, Citocalasina D/farmacologia, Citocalasina D/metabolismo, Ceco/metabolismo, Artérias Carótidas/metabolismo, Cálcio/metabolismo
19.
Neurosurg Rev ;47(1): 141, 2024 Apr 05.
ArtigoemInglês |MEDLINE | ID: mdl-38578556

RESUMO

BACKGROUND AND PURPOSE: The classic Shamblin system fails to provide valuable guidance in many Shamblin's III carotid body tumors (III-CBTs) due to the variable forms of carotid arteries and the complex anatomic relationships in parapharyngeal space. We proposed a modified classification to separately divide III-CBTs into different subgroups on the basis of arterial relevant features and anatomical relevant features. MATERIALS AND METHODS: From 2020 to 2023, a total of 129 III-CBTs at a single institution were retrospectively analyzed. All cases were independently classified as arterial-relevant and anatomical-relevant subgroups. The pre-, peri- and postoperative data were summarized and compared accordingly. RESULTS: Among the 129 cases, 69 cases were identified as "Classical type", 23 cases as "Medial type", 27 cases as "Lateral type" and 10 cases as "Enveloped type" according to arterial morphologies. Besides, 76 cases were identified as "Common type", 15 cases as "Pharynx- invasion type", 18 cases as "Skull base-invasion type" and 20 cases as "Mixed type" according to anatomical relationships. "Enveloped type" of tumors in arterial-relevant classification and "Mixed type" of tumors in anatomical-relevant classification are the most challenging cases for surgeons with the lowest resection rate, highest incidence of carotid arteries injury and postoperative stroke. CONCLUSION: The modified classifications provide comprehensive understanding of different III-CBTs which are applicable for individualized treatment in clinical practice.


Assuntos
Tumor do Corpo Carotídeo, Humanos, Tumor do Corpo Carotídeo/cirurgia, Tumor do Corpo Carotídeo/patologia, Estudos Retrospectivos, Procedimentos Cirúrgicos Vasculares, Artérias Carótidas/patologia, Incidência, Resultado do Tratamento
20.
Sci Rep ;14(1): 8407, 2024 04 10.
ArtigoemInglês |MEDLINE | ID: mdl-38600230

RESUMO

Elevated remnant cholesterol (RC) is considered a risk factor for atherosclerotic cardiovascular disease, but the evidence on this association applies to the Chinese population with hypertension is limited. We aimed to explore the association between RC levels and carotid plaque in old adults with hypertension. 8523 hypertensive patients aged ≥ 60 years with serum lipids and carotid ultrasonography data were included in this community-based screening. Fasting RC was calculated as total cholesterol minus high-density lipoprotein cholesterol minus low-density lipoprotein cholesterol (LDLC). The associations of RC levels with carotid plaque risk were evaluated using Logistic regression and restricted cubic spline models. Carotid plaque was screened in 4821 (56.56%) subjects. After multivariable-adjusted, RC was significantly related to carotid plaque [Odd ratio (OR)] = 1.043 per 0.1 mmol/L increase, 95% confidence interval (CI): 1.030-1.056). The highest versus the lowest quartile of RC was 1.928 (1.673-2.223) for carotid plaque. A nonlinear association was found between serum RC levels and the risk of carotid plaque (P for nonlinearity < 0.001). Moreover, an RC > 0.78 mmol/L differentiated patients at a higher risk of carotid plaque compared to those at lower concentrations, regardless of whether LDLC was on target at 2.59 mmol/L. In old adults with hypertension, elevated RC was positively associated with carotid plaque, independent of LDLC and other conventional risk factors.


Assuntos
Aterosclerose, Hipercolesterolemia, Hipertensão, Placa Aterosclerótica, Adulto, Humanos, Colesterol, Hipertensão/complicações, Hipertensão/epidemiologia, Artérias Carótidas, Aterosclerose/complicações, Fatores de Risco, Hipercolesterolemia/complicações, China/epidemiologia
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