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Byline: Hiroki. Uchikawa, Kazumi. Nitta, Yukihiro. Imaoka, Akira. Tempaku, Hironori. Arima, Akitake. Mukasa, Hajime. Kamada Background: Endovascular treatment is the preferred treatment for acute ischemic stroke (AIS) due to main [...]

Post-spaceflight orthostatic intolerance is one of the most important adverse effects after exposure to space microgravity, and there are still no effective countermeasures. It has been considered that arterial remodeling may play an important role in the occurrence of post-spaceflight orthostatic intolerance, but the cellular mechanisms remain unknown. In this study, we investigated whether an inflammatory response exists in the common carotid artery of rats exposed to simulated microgravity. For this, Sprague-Dawley rats were subjected to 4 weeks of hindlimb unweighting to simulate microgravity. The expression levels of the adhesion molecules E-selectin and vascular cell adhesion molecule-1 (VCAM-1), and the cytokine monocyte chemoattractant protein-1 (MCP-1) in the common carotid artery of simulated microgravity rats were evaluated by immunohistochemical staining, quantitative RT-PCR, and Western blot analyses. The recruitment of monocytes in the common carotid artery of rats exposed to simulated microgravity was investigated by en face immunofluorescence staining and monocyte binding assays. Our results provided convincing evidence that there is an inflammatory response in the common carotid artery of rats exposed to simulated microgravity. Our work suggests that the inflammatory response may be a novel cellular mechanism that is responsible for the arterial remodeling that occurs during exposure to microgravity. Key words: simulated microgravity, common carotid artery, arterial remodeling, inflammatory response, hindlimb unweighted. L'intolerance orthostatique apres un vol spatial est un des effets secondaires les plus importants de l'exposition a la microgravite spatiale et il n'existe encore aucune mesure preventive efficace. Il a ete considere que le remodelage arteriel puisse jouer un role important dans la survenue de l'intolerance orthostatique apres un vol spatial, mais les mecanismes cellulaires demeurent inconnus. Dans la presente etude, les auteurs ont voulu savoir s'il existait une reponse inflammatoire dans l'artere carotide commune de rats places en microgravite simulee. Des rats Sprague-Dawley ont ete soumis a un allegement des membres posterieurs pendant 4 semaines afin de simuler la microgravite. Les niveaux d'expression de molecules d'adhesion [E-selectine et la molecule d'adhesion cellulaire vasculaire VCAM-1 (vascular cell adhesion molecule-1)] et d'une cytokine [la proteine MCP-1 (monocyte chemoattractant protein-1)] dans l'artere carotide commune de rats places en microgravite simulee ont ete evalues par coloration immunohistochimique, RT-PCR quantitative et par buvardage Western. Le recrutement de monocytes dans l'artere carotide commune des rats places en microgravite simulee a ete examine par une coloration en immunofluorescence et par des tests de liaison de monocytes. Les resultats fournissent des preuves convaincantes qu'il existe une reponse inflammatoire dans l'artere carotide commune des rats places en microgravite simulee. Le travail des auteurs suggere que la reponse inflammatoire pourrait constituer un nouveau mecanisme cellulaire responsable du remodelage arteriel lors de l'exposition a la microgravite. [Traduit par la Redaction] Mots-cles : microgravite simulee, artere carotide commune, remodelage arteriel, reponse inflammatoire, allegement des membres posterieurs., Introduction Post-spaceflight orthostatic intolerance has been regarded as one of the most important adverse effects after exposure to microgravity, and there have been no effective countermeasures until now (Buckey et [...]

Objective: To assess the association between the intake of dietary fibre and carotid intima-media thickness (IMT) in a Mediterranean population at high cardiovascular risk. Methods: Baseline cross-sectional assessment of 457 men and women (average age 67 years) from two different Spanish centres of the PREDIMED trial. A previously validated food frequency questionnaire (137 food items) was administered by trained dieticians in a face-to-face interview. Mean common carotid IMT was measured using B-mode ultrasound imaging of the right and left carotid arteries by four certified sonographers who used a common protocol. Anthropometric and blood pressure measurements were performed and samples of fasting blood were obtained. Participants were categorized into four groups (roughly quartiles: [less than or equal to] 21; >21 to [less than or equal to] 25; >25 to [less than or equal to] 31 and >31 g/day) of energy-adjusted intake of dietary fibre. Multiple linear regression models were used to adjust for age, sex, centre, smoking, body mass index, diabetes, blood pressure, lipid levels and statin use. Results: In the crude analyses, energy-adjusted fibre intake showed a significant inverse correlation with IMT (r= -0.27, P35g/day, (n=47) when compared with those whose intake was Conclusions: Our results suggest that high fibre intake is inversely associated with carotid atherosclerosis. doi:10.1038/ejcn.2009.45; published online 24 June 2009 Keywords: Cardiovascular disease; carotid intima-media thickness; dietary fibre; cardiovascular risk; atherosclerosis; Mediterranean diet, Introduction Dietary fibre (DF) intake in western countries has been decreasing in the last decades, and many countries have made recommendations to the population to increase consumption of fibre-rich foods [...]

Store-operated channels (SOC) and store-operated [Ca.sup.2+] entry are known to play a major role in agonist-induced constriction of smooth muscle cells (SMC) in conduit vessels. In microvessels the role of SOC remains uncertain, in as much as voltage-gated L-type [Ca.sup.2+] ([Ca.sup.2+.sub.L]) channels are thought to be fully responsible for agonist-induced [Ca.sup.2+] influx and vasoconstriction. We present evidence that SOC and their activation via a [Ca.sup.2+] -independent phospholipase [A.sub.2] ([iPLA.sub.2])-mediated pathway play a crucial role in agonist-induced constriction of cerebral, mesenteric, and carotid arteries. Intracellular [Ca.sup.2+] in SMC and intraluminal diameter were measured simultaneously in intact pressurized vessels in vitro. We demonstrated that 1) [Ca.sup.2+] and contractile responses to phenylephrine (PE) in cerebral and carotid arteries were equally abolished by nimodipine (a [Ca.sup.2.sub.L+] inhibitor) and 2-aminoethyl diphenylborinate (an inhibitor of SOC), suggesting that SOC and [Ca.sup.2.sub.L+] channels may be involved in agonist-induced constriction of cerebral arteries, and 2) functional inhibition of [iPLA.sub.2][beta] totally inhibited PE-induced [Ca.sup.2+] influx and constriction in cerebral, mesenteric, and carotid arteries, whereas [K.sup.+]-induced [Ca.sup.2+] influx and vasoconstriction mediated by [Ca.sup.2+.sub.L] channels were not affected. Thus [iPLA.sub.2]-dependent activation of SOC is crucial for agonist-induced [Ca.sup.2+] influx and vasoconstriction in cerebral, mesenteric, and carotid arteries. We propose that, on PE-induced depletion of [Ca.sup.2+] stores, nonselective SOC are activated via an [iPLA.sub.2]-dependent pathway and may produce a depolarization of SMC, which could trigger a secondary activation of [Ca.sup.2+.sub.L] channels and lead to [Ca.sup.2+] entry and vasoconstriction. store-operated calcium entry; smooth muscle cells; constriction

The degree of variability in the temperature difference between the brain and carotid arterial blood is greater than expected from the presumed tight coupling between brain heat production and brain blood flow. In animals with a carotid rete, some of that variability arises in the rete. Using thermometric data loggers in five sheep, we have measured the temperature of arterial blood before it enters the carotid rete and after it has perfused the carotid rete, as well as hypothalamic temperature, every 2 min for between 6 and 12 days. The sheep were conscious, unrestrained, and maintained at an ambient temperature of 20-22[degrees]C. On average, carotid arterial blood and brain temperatures were the same, with a decrease in blood temperature of 0.35[degrees]C across the rete and then an increase in temperature of the same magnitude between blood leaving the rete and the brain. Rete cooling of arterial blood took place at temperatures below the threshold for selective brain cooling. All of the variability in the temperature difference between carotid artery and brain was attributable statistically to variability in the temperature difference across the rete. The temperature difference between arterial blood leaving the rete and the brain varied from -0.1 to 0.9[degrees]C. Some of this variability was related to a thermal inertia of the brain, but the majority we attribute to instability in the relationship between brain blood flow and brain heat production. brain blood flow; selective brain cooling; sheep; thermoregulation

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1177/1051228405001523 Byline: Pornpatr Likittanasombut (1), Patrick Reynolds (1), Dana Meads (1), Charles Tegeler (1) Keywords: Ultrasound; Volume flow rate; Catatid stenosis Abstract: ABSTRACT Background. Common carotid artery (CCA) volume flow rate (VFR) is clinically useful for study of cerebrovascular disease. Color Velocity Imaging Quantification (CVI-Q; Philips Ultrasound International, Irvine, CA), previously reported as accurate and reliable, tracks the flow lumen over the cardiac cycle, as well as mean spatial velocity, which is multiplied by vessel area to obtain VFR. VFR can also be obtained by Doppler sampling for mean velocity, and vessel area based on static B-mode lumen diameter. We compared CCA VFR by CVI-Q and Doppler method (DM), since knowledge of how they compare is crucial when both are used clinically. Method. We prospectively studied patients having clinical carotid duplex exams and healthy controls. All had CCA VFR measured by both methods in the same exam session. Results. Thirty-four studies were reviewed. CCA VFR by CVI-Q in those without ICA stenosis was 337 [+ or -] 96 mL/m, and by DM 359 [+ or -] 130 mL/m; P= .33. There was no difference between methods for 50-75% or 75-95% ICA stenosis. In 7 patients with ICA occlusion, and 3 with 95-99% stenosis, VFR was higher by DM than by CVI-Q (Occlusion: 125 vs 58 mL/m, P= .007; 95-99%: 152 vs 63 mL/m, P= .038). There was no statistically significant difference between methods for measurement of the ratio of VFR between right and left CCA. Conclusion. In patients with 0-95% ICA stenosis, VFR by CVI-Q and DM showed no difference. For 95-100% ICA stenosis the methods differ; with higher VFR by DM. Side-to-side VFR ratios remain constant, irrespective of VFR method, and can still provide clinically useful information. Author Affiliation: (1)From the Department of Neurology, Department of Medicine, Faculty of Medicine, Thammasat University, Patumthani, Thailand and the Department of Neurology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, North Carolina. Article History: Received November 1, 2004, and in revised form June 27, 2005. Accepted for publication August 4, 2005. Article note: Address correspondence to Charles Tegeler, MD, Department of Neurology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC 27157-1078. E-mail: ctegeler@wfubmc.edu.

BACKGROUND: Subclinical atherosclerosis has been associated with long-term exposure to particulate matter (PM), but the relevance of particle size and sources of exposure remains unclear. OBJECTIVES: We investigated the association of long-term exposure to [PM.sub.10] (≤ 10 µm), [PM.sub.2.5] ([less than or equal to] 2.5 µm: total mass, vehicular, and crustal sources), and ultrafine particles [UFP < 0.1 µm: particle number concentration (PNC) and lung-deposited surface area (LDSA)] with carotid intima-media thickness (CIMT). METHODS: We used data from 1,503 participants [greater than or equal to] 50 years old who participated in the third examination of the Swiss SAPALDIA cohort. Exposures were obtained from dispersion models and land-use regression models. Covariate information, including previous cardiovascular risk factors, was obtained from the second and third SAPALDIA examinations. RESULTS: The adjusted percent difference in CIMT associated with an exposure contrast between the 10th and 90th percentile was 1.58% (95% CI: -0.30, 3.47%) for [PM.sub.10], 2.10% (95% CI: 0.04, 4.16%) for [PM.sub.2.5], 1.67% (95% CI: -0.13, 3.48%) for the vehicular source of [PM.sub.2.5], -0.58% (95% CI: -3.95, 2.79%) for the crustal source of [PM.sub.2.5], 2.06% (95% CI: 0.03, 4.10%) for PNC, and 2.32% (95% CI: 0.23, 4.40%) for LDSA. Stronger associations were observed among diabetics, subjects with low-educational level, and those at higher cardiovascular risk. CONCLUSIONS: CIMT was associated with exposure to [PM.sub.10], [PM.sub.2.5], and UFP. The [PM.sub.2.5] sourcespecific analysis showed a positive association for the vehicular source but not for the crustal source. Although the effects of PNC and LDSA were similar in magnitude, two-pollutant and residual-based models suggested that LDSA may be a better marker for the health relevance of UFP. http://dx.doi.org/10.1289/EHP161, Introduction Epidemiological and experimental research has provided sufficient evidence for a causal effect of ambient air pollution [mainly particulate matter (PM)] on cardiovascular mortality and morbidity (Brook et al. 2010). [...]

A SURGICAL PROCEDURE to prevent strokes, involving the removal of plaque from the carotid artery, has a greater chance of ending in the death of the patient when the surgery [...]

A debate on whether the US food and Drug Administration would approve a stent for stenosis is discussed. Those who perform cartoid artery stenting say that their procedure is ready to become the most sought after treatment.

People whose carotid arteries are clogged with plaque, and who have had a stroke or mini-strokes (called TIAs), or who show symptoms of brain function loss to to the narrowing [...]