Int J Numer Method Biomed Eng
November 2023
The heterogeneous model developed by Berod et al [Int J Numer Method Biomed Eng 38, 2021] for representing the hemodynamic effects of endovascular prostheses is applied to a series of 10 patient specific cerebral aneurysms, 6 being treated by flow diverters, 4 being equipped with WEBs. Two markers correlated with the medical outcome of the treatment are used to assess the potential of the model, namely the saccular mean velocity and the inflow rate at the neck of the aneurysm. The comparison with the corresponding wire-resolved simulations is very favorable in both cases, and the model-based simulations also retrieve the jetting-type flows generated downstream of the struts.
View Article and Find Full Text PDFIntroduction: The Woven EndoBridge device (WEB) was developed as an alternative to treat Wide-Necked bifurcation aneurysms. It has proven to be effective and safe, however, cases of recanalization have been reported. The purpose of this study was to evaluate and quantify hemodynamic parameters and indexes with CFD of the intracranial aneurysms before and after WEB simulation and to establish their relationship to complete occlusion.
View Article and Find Full Text PDFIntroduction: The Woven EndoBridge device (WEB) is used to treat wide-neck bifurcation aneurysms. These devices are deployed inside the sac. Therefore, the mesh structure provides apposition with the aneurysm wall and induces aneurysmal thrombosis.
View Article and Find Full Text PDF. Intraventricular vector flow mapping (VFM) is a velocimetric technique for retrieving two-dimensional velocity vector fields of blood flow in the left ventricular cavity. This method is based on conventional color Doppler imaging, which makesVFM compatible with the clinical setting.
View Article and Find Full Text PDFColor Doppler by transthoracic echocardiography creates two-dimensional fan-shaped maps of blood velocities in the cardiac cavities. It is a one-component velocimetric technique since it only returns the velocity components parallel to the ultrasound beams. Intraventricular vector flow mapping (VFM) is a method to recover the blood velocity vectors from the Doppler scalar fields in an echocardiographic three-chamber view.
View Article and Find Full Text PDFInt J Numer Method Biomed Eng
February 2022
Numerical computations of hemodynamics inside intracranial aneurysms treated by endovascular braided devices such as flow-diverters contribute to understanding and improving such treatment procedures. Nevertheless, these simulations yield high computational and meshing costs due to the heterogeneity of length scales between the dense weave of the fine struts of the device and the arterial volume. Homogeneous strategies developed over the last decade to circumvent this issue substitute local dissipations due to the wires with a global effect in the form of a pressure-drop across the device surface.
View Article and Find Full Text PDFThe present study examined whether children with autism spectrum disorder (ASD) and typically developing (TD) children differed in visual perception of food stimuli at both sensorimotor and affective levels. A potential link between visual perception and food neophobia was also investigated. To these aims, 11 children with ASD and 11 TD children were tested.
View Article and Find Full Text PDFNeurosci Biobehav Rev
June 2017
Depression and substance use disorder (SUD) often co-exist and are typically associated with an inaccurate diagnosis, worsened clinical course and poor medication adherence compared to either disorder alone. To date, the biological mechanisms contributing to their strong association remain largely unknown. In this review, we critically analyze preclinical literature on psychostimulant drugs and reconsider the common view that depression is a risk factor for drug use and the development of SUD.
View Article and Find Full Text PDFEvidence accumulates suggesting a complex interplay between neurodegenerative processes and serotonergic neurotransmission. We have previously reported an overexpression of serotonin 5-HT1A receptors (5-HT(1A)R) after intrahippocampal injections of amyloid-beta 1-40 (Aβ40) fibrils in rats. This serotonergic reactivity paralleled results from clinical positron emission tomography studies with [(18)F]MPPF revealing an overexpression of 5-HT(1A)R in the hippocampus of patients with mild cognitive impairment.
View Article and Find Full Text PDFBackground: Major depression has multiple comorbidities, in particular drug use disorders, which often lead to more severe and difficult-to-treat illnesses. However, the mechanisms linking these comorbidities remain largely unknown.
Methods: We investigated how a depressive-like phenotype modulates cocaine-related behaviors using a genetic model of depression: the Helpless H/Rouen (H) mouse.
Objectives: To assess the impact of lymphovascular invasion (LVI) on upper urinary tract urothelial carcinomas (UTUCs) in a multicentre study on cancer-specific survival (CSS), recurrence-free survival and metastasis-free survival (MFS). To show the negative impact of LVI for patients with pN0/x disease and to stratify these patients into risk groups for metastatic relapse.
Patients And Methods: A multicentre retrospective study was performed on patients who underwent radical nephroureterectomy between 1995 and 2010.
Unlabelled: Study Type--Prognosis (cohort) Level of Evidence 2b. What's known on the subject? and What does the study add? Upper urinary tract urothelial carcinoma (UUT-UC) is a rare disease, usually treated by nephroureterectomy, occurring in a population with a median age of 70 years and with frequent tobacco use and other comorbidities. We know that the American Society of Anesthesiologists (ASA) score has prognostic value in urological oncology but this has not been assessed in UUT-UC.
View Article and Find Full Text PDFPurpose: The management of high grade blunt renal injury has evolved with time to become increasingly conservative with the ultimate objective of renal preservation. We evaluated relative renal function with dimercapto-succinic acid renal scintigraphy 6 months after major renal trauma (grade IV or V).
Materials And Methods: This prospective observational study was done between January 2004 and April 2010.
Study Objectives: To determine whether sublaterodorsal tegmental nucleus (SLD) neurons triggering paradoxical (REM) sleep (PS) are glutamatergic.
Design: Three groups of rats were used: controls, rats deprived of PS for 72 h, and rats allowed to recover for 3 h after deprivation. Brain sections were processed for double labeling combining Fos immunohistochemistry and vesicular glutamate transporter 2 (vGLUT2) in situ hybridization.
Current antidepressants still display unsatisfactory efficacy and a delayed onset of therapeutic action. Here we show that the pharmacological blockade of serotonin 7 (5-HT(7)) receptors produced a faster antidepressant-like response than the commonly prescribed antidepressant fluoxetine. In the rat, the selective 5-HT(7) receptor antagonist SB-269970 counteracted the anxiogenic-like effect of fluoxetine in the open field and exerted an antidepressant-like effect in the forced swim test.
View Article and Find Full Text PDFWe recently discovered, using Fos immunostaining, that the tuberal and mammillary hypothalamus contain a massive population of neurons specifically activated during paradoxical sleep (PS) hypersomnia. We further showed that some of the activated neurons of the tuberal hypothalamus express the melanin concentrating hormone (MCH) neuropeptide and that icv injection of MCH induces a strong increase in PS quantity. However, the chemical nature of the majority of the neurons activated during PS had not been characterized.
View Article and Find Full Text PDFA recent [(18)F]MPPF-positron emission tomography study has highlighted an overexpression of 5-HT(1A) receptors in the hippocampus of patients with mild cognitive impairment compared to a decrease in those with Alzheimer's disease (AD) [Truchot, L., Costes, S.N.
View Article and Find Full Text PDFParadoxical sleep (PS) is a state characterized by cortical activation, rapid eye movements and muscle atonia. Fifty years after its discovery, the neuronal network responsible for the genesis of PS has been only partially identified. We recently proposed that GABAergic neurons would have a pivotal role in that network.
View Article and Find Full Text PDFThe purpose of this study was to further address the hypothesis that ethanol activates GABAergic neurons in specific brain neurocircuits that mediate motivated behavior and control of action, such as the central extended amygdala and medial prefrontal cortex. Male Sprague-Dawley rats received habituation to 7 days of daily intragastric administration of water (5 ml/kg) followed by a single acute intragastric dose of ethanol (2.5 g/kg) or water then, 2 h later, by paraformaldehyde perfusion.
View Article and Find Full Text PDFThis study examined the long-term effects of the antidepressant escitalopram on rat serotonin (5-HT) neuronal activity and hippocampal neuroplasticity. In the dorsal raphe nucleus, a 2-week treatment with escitalopram (10 mg/kg/day, subcutaneous) did not modify the firing activity of 5-HT neurons, whereas a cotreatment with R-citalopram (20 mg/kg/day, subcutaneous) decreased it. In the dentate gyrus of dorsal hippocampus, escitalopram increased significantly (57%) the number of de novo cells and this was prevented by a cotreatment with R-citalopram.
View Article and Find Full Text PDFThe ventral tegmental area (VTA), primary source of the mesocorticolimbic dopaminergic system, is regarded as a critical site for initiation of behavioural sensitization to psychostimulants. The present study was undertaken to identify the neural pathways converging on the VTA that are potentially implicated in this process. Rats were sensitized by a single exposure to amphetamine (5 mg/kg, s.
View Article and Find Full Text PDFNeurons expressing VIP/PHI precursor mRNA have been localized in the interstitial nucleus of Cajal. Unilateral surgical cut through the medial forebrain bundle failed to influence VIP/PHI mRNA expression in the Cajal nucleus while brainstem hemisection or unilateral transection of the medial longitudinal fascicle reduced it markedly, ipsilateral to the knife cuts. Thus, in contrast to forebrain projecting VIP neurons in the rostral periaqueductal gray, VIP/PHI neurons in the Cajal nucleus project downwards, to the lower brainstem.
View Article and Find Full Text PDFChronic use of psychostimulants induces enduringly increased responsiveness to a subsequent psychostimulant injection and sensitivity to drug-associated cues, contributing to drug craving and relapse. Neurotensin (NT), a neuropeptide functionally linked to dopaminergic neurons, was suggested to participate in these phenomena. We and others have reported that SR 48692, an NT receptor antagonist, given in pre- or co-treatments with cocaine or amphetamine, alters some behavioral effects of these drugs in rats.
View Article and Find Full Text PDFNeurotensin (NT) is a peptide that is widely distributed throughout the brain. NT is involved in locomotion, reward, stress and pain modulation, and in the pathophysiology of drug addiction and depression. In its first part this review brings together relevant literature about the neuroanatomy of NT and its receptors.
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